The present invention relates to photochromic polydiorganosiloxane vinylic crosslinkers each having one or more photochromic siloxane units having one methyl substituent and one organic substituent having one photochromic group capable of undergoing a reversible color change upon exposure to UV-irradiation or high-energy- violet light (HEVL) and their uses in making photochromic ophthalmic devices, in particular, photochromic silicone hydrogel contact lenses.

BACKGROUND OF THE INVENTION

Conventionally, UV-absorbing compounds have been incorporated into contact lenses to make UV-absorbing contact lenses to protect eyes from UV-radiations.

Recently, there have been proposed various photochromic contact lenses for protecting eyes from UV-radiations (see, e.g., U.S. Pat. Nos. 4681412, 6017121 , 6174464,

6224945, 7261844, 7368072,, 7556750, 7560056, 7584630, 7641337, 7999989,

8158037, 8697770, 8741188, 9052438, 9097916, 9377569, 9465234, 9904074, 10197707). Those proposed photochromic contact lenses contains photochromic compounds which are capable of undergoing a reversible color change, e.g., from “clear” to blue or other color, upon exposure to UV-irradiation.

Typically, photochromic contact lenses can be obtained by adding a polymerizable photochromic compound in a polymerizable composition (i.e., lens formulation) for forming the contact lenses and then by curing the polymerizable composition in contact lens molds according to a conventional cast-molding lens manufacturing process.

However, known polymerizable photochromic compounds have limited compatibility with the polymerizable components, in particular, polymerizable hydrophilic components, in a lens formulation for making silicone hydrogel contact lenses, due to their very bulky and hydrophobic structures. Such a limited compatibility poses a great challenge in formulating a lens formulation for making optically-clear and photochromic silicone hydrogel contact lenses.

Furthermore, although known polymerizable photochromic compounds are chemically incorporated into the polymer matrix of a silicone hydrogel contact lens, they are still susceptible to hydrolysis, especially when they are located in hydrophilic microscopic regions containing water in a silicone hydrogel contact lens. Slow hydrolysis could slowly reduce the photochromic capability/property of the silicone hydrogel contact lenses.

In addition, it is desirable to have relatively high activation and deactivation rates of photochromic moieties in contact lenses, so that the contact lenses can undergo rapidly reversible color change upon exposure to UV-irradiation or HEVL-irradiation.

Therefore, there is still a need for polymerizable photochromic compounds which are more compatible with the polymerizable components of a lens formulation and suitable for producing photochromic silicone hydrogel contact lenses that can have a long-lasting photochromic property and can undergo rapidly a reversible color change upon exposure to UV-irradiation or HEVL-irradiation.

SUMMARY OF THE INVENTION

The present invention, in one aspect, provides a photochromic polysiloxane vinylic crosslinker. The photochromic polydiorganosiloxane vinylic crosslinker of the invention comprises: (1) a polydiorganosiloxane segment comprising dimethylsiloxane units and photochromic siloxane unit having one methyl substituent and one organic substituent having a photochromic group; (2) two terminal ethylenically-unsaturated groups.

In another aspect, the invention provides a soft contact lens comprising a crosslinked polymeric material comprising units of a photochromic polydiorganosiloxane vinylic crosslinker of the invention (described above).

The present invention provides the foregoing and other features, and the advantages of the invention will become further apparent from the following detailed description of the presently preferred embodiments, read in conjunction with the accompanying figures. The detailed description and figures are merely illustrative of the invention and do not limit the scope of the invention, which is defined by the appended claims and equivalents thereof.

DESCRIPTION OF PREFERRED EMBODIMENTS

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Generally, the nomenclature used herein and the laboratory procedures are well known and commonly employed in the art. Conventional methods are used for these procedures, such as those provided in the art and various general references. Where a term is provided in the singular, the inventors also contemplate the plural of that term. The nomenclature used herein and the laboratory procedures described below are those well-known and commonly employed in the art.

"About" as used herein in this application means that a number, which is referred to as "about", comprises the recited number plus or minus 1 -10% of that recited number.

An "ophthalmic device", as used herein, refers to a contact lens (hard or soft), an intraocular lens, a corneal onlay, other ophthalmic devices (e.g., stents, glaucoma shunt, or the like) used on or about the eye or ocular vicinity.

“Contact Lens” refers to a structure that can be placed on or within a wearer's eye. A contact lens can correct, improve, or alter a user's eyesight, but that need not be the case. A contact lens can be of any appropriate material known in the art or later developed, and can be a soft lens, a hard lens, or a hybrid lens. A “silicone hydrogel contact lens” refers to a contact lens comprising a silicone hydrogel material.

A “hydrogel” or “hydrogel material” refers to a crosslinked polymeric material which has three-dimensional polymer networks (i.e., polymer matrix), is insoluble in water, but can hold at least 10% by weight of water in its polymer matrix when it is fully hydrated (or equilibrated).

A “silicone hydrogel” refers to a silicone-containing hydrogel obtained by copolymerization of a polymerizable composition comprising at least one silicone- containing monomer or at least one silicone-containing macromer or at least one crosslinkable silicone-containing prepolymer.

A siloxane, which often also described as a silicone, refers to a molecule having at least one moiety of -Si-O-Si- where each Si atom carries two organic groups as substituents.

As used in this application, the term “non-silicone hydrogel” refers to a hydrogel that is theoretically free of silicon.

“Hydrophilic,” as used herein, describes a material or portion thereof that will more readily associate with water than with lipids.

A “vinylic monomer” refers to a compound that has one sole ethylenically unsaturated group, is soluble in a solvent, and can be polymerized actinically or thermally.

The term “soluble”, in reference to a compound or material in a solvent, means that the compound or material can be dissolved in the solvent to give a solution with a concentration of at least about 0.5% by weight at room temperature (i.e., a temperature of about 21 °C to about 27°C).

The term “insoluble”, in reference to a compound or material in a solvent, means that the compound or material can be dissolved in the solvent to give a solution with a concentration of less than 0.01% by weight at room temperature (as defined above).

The term “ethylenically unsaturated group” is employed herein in a broad sense and is intended to encompass any groups containing at least one >C=C< group.

Exemplary ethylenically unsaturated groups include without limitation (meth)acryloyl ; allyl, vinyl, styrenyl, or other C=C containing groups.

As used herein, “actinically” in reference to curing, crosslinking or polymerizing of a polymerizable composition, a prepolymer or a material means that the curing (e.g., crosslinked and/or polymerized) is performed by actinic irradiation, such as, for example, UV irradiation, ionizing radiation (e.g. gamma ray or X-ray irradiation), microwave irradiation, and the like. Thermal curing or actinic curing methods are well-known to a person skilled in the art.

An “acrylic monomer” refers to a vinylic monomer having one sole (meth)acryloyl group. Examples of acrylic monomrs includes (meth)acryloxy [or(meth)acryloyloxy] monomers and (meth)acrylamido monomers.

An “(meth)acryloxy monomer” or “(meth)acryloyloxy monomer” refers to a vinylic monomer having one sole group of .

An “(meth)acrylamido monomer” refers to a vinylic monomer having one sole group of in which R° is H or C ₁ -C ₄ alkyl.

The term “(meth)acrylamide” refers to methacrylamide and/or acrylamide.

The term “(meth)acrylate” refers to methacrylate and/or acrylate.

An “N-vinyl amide monomer” refers to an amide compound having a vinyl group ( ^{— CH=CH} 2) that is directly attached to the nitrogen atom of the amide group.

The term “ene group” refers to a monovalent radical of CH ₂ =CH- or CH ₂ =CCH ₃ - that is not covalently attached to an oxygen or nitrogen atom or a carbonyl group.

An “ene monomer” refers to a vinylic monomer having one sole ene group.

A “hydrophilic vinylic monomer”, a “hydrophilic acrylic monomer”, a “hydrophilic (meth)acryloxy monomer”, or a “hydrophilic (meth)acrylamido monomer”, as used herein, respectively refers to a vinylic monomer, an acrylic monomer, a (meth)acryloxy monomer, or a (meth)acrylamido monomer), which typically yields a homopolymer that is water- soluble or can absorb at least 10 percent by weight of water.

A “hydrophobic vinylic monomer”, a “hydrophobic acrylic monomer”, a “hydrophobic (meth)acryloxy monomer”, or a “hydrophobic (meth)acrylamido monomer”, as used herein, respectively refers to a vinylic monomer, an acrylic monomer, a (meth)acryloxy monomer, or a (meth)acrylamido monomer), which typically yields a homopolymer that is insoluble in water and can absorb less than 10% by weight of water.

As used in this application, the term “vinylic crosslinker” refers to an organic compound having at least two ethylenically unsaturated groups. A “vinylic crosslinking agent” refers to a vinylic crosslinker having a molecular weight of 700 Daltons or less.

A “polysiloxane segment” or “polydiorganosiloxane segment” interchangeably refers to a polymer chain segment (i.e., a divalent radical) of in which SN is an integer of 3 or larger and each of Rsi and Rs ₂ independent of one another are selected from the group consisting of: C ₁ -C ₁₀ alkyl; phenyl; C ₁ -C ₄ -alkyl-substituted phenyl; C ₁ -C ₄ - alkoxy-substituted phenyl; phenyl-Ci-C ₆ -alkyl; C ₁ -C ₁₀ fluoroalkyl; C ₁ -C ₁₀ fluoroether; aryl; aryl C ₁ -C ₁₈ alkyl; -alk-(OC ₂ H ₄ ) _Y1 -OR ⁰ (in which alk is C ₁ -C ₆ alkylene diradical, R° is H or C ₁ -C ₄ alkyl and g1 is an integer from 1 to 10); a C ₂ -C ₄₀ organic radical having at least one functional group selected from the group consisting of hydroxyl group (-OH ), carboxyl group (-COOH), amino group (-NRNI RNI’), amino linkages of -NRNI-, amide linkages of - CONRNI-, amide of -CONRNI RNI’, urethane linkages of -OCONH-, and C1-C4 alkoxy group, or a linear hydrophilic polymer chain, in which R _N1 and R _{N1 ’} independent of each other are hydrogen or a C ₁ -C ₁₅ alkyl; and a photochromic organic radical having a photochromic group.

A “polydiorganosiloxane vinylic crosslinker” or polysiloxane vinylic crosslinker” interchangeably refers to a compound comprising at least one polysiloxane segment and at least two ethylenically-unsaturated groups.

A “linear polydiorganosiloxane vinylic crosslinker” or “linear polysiloxane vinylic crosslinker” interchangeably refers to a compound comprising a main chain which includes at least one polysiloxane segment and is terminated with one ethylenically- unsaturated group at each of the two ends of the main chain.

A “chain-extended polydiorganosiloxane vinylic crosslinker” or “chain-extended polysiloxane vinylic crosslinker” interchangeably refers to a compound comprising at least two ethylenically-unsaturated groups and at least two polysiloxane segments each pair of which are linked by one divalent radical.

The term “azlactone” refers to a mono-valent radical of in which p is 0 or

1 ; Ti and T ₂ independently of each other is H or C ₁ -C ₈ alkyl (preferably methyl).

The term “photochromic group” refers to a monovalent organic radical that has one colorless (or light-colored) form and one colored form and can undergo reversible change from the colorless form (or light-colored form) to the colored form upon exposure to UV-irradiation or HEV light. In accordance with the invention, a photochromic group is derived directly from a photochromic compound that has a reactive functional group (e.g., hydroxyl group, carboxyl group, primary amino group, secondary amino group, isocyanate group, epoxy group, aziridine group, thiol group, -CHO, a ketone group, ene group, vinyl, vinylsulfonyl, acryloyl, methacryloyl, etc.) that has participated in a coupling reaction with a co-reactive functional group of another compound or material to form a covalent linkage between the photochromic group and the another compound or material.

The term “fluid” as used herein indicates that a material is capable of flowing like a liquid.

As used in this application, the term “clear” in reference to a polymerizable composition means that the polymerizable composition is a transparent solution or liquid mixture having a light transmissibility of 85% or greater (preferably 90% or greater) in the range between 400 to 700 nm.

As used in this application, the term “polymer” means a material formed by polymerizing/crosslinking one or more monomers or macromers or prepolymers or combinations thereof.

A “macromer” or “prepolymer” refers to a compound or polymer that contains ethylenically unsaturated groups and has a number average molecular weight of greater than 700 Daltons.

As used in this application, the term “molecular weight” of a polymeric material (including monomeric or macromeric materials) refers to the number-average molecular weight unless otherwise specifically noted or unless testing conditions indicate otherwise. A skilled person knows how to determine the molecular weight of a polymer according to known methods, e.g., GPC (gel permeation chromatochraphy) with one or more of a refractive index detector, a low-angle laser light scattering detector, a multi-angle laser light scattering detector, a differential viscometry detector, a UV detector, and an infrared (IR) detector; MALDI-TOF MS (matrix-assisted desorption/ionization time-of-flight mass spectroscopy); ¹ H NMR (Proton nuclear magnetic resonance) spectroscopy, etc.

The term “monovalent radical” refers to an organic radical that is obtained by removing a hydrogen atom from an organic compound and that forms one bond with one other group in an organic compound. Examples include without limitation, alkyl (by removal of a hydrogen atom from an alkane), alkoxy (or alkoxyl) (by removal of one hydrogen atom from the hydroxyl group of an alkyl alcohol), thiyl (by removal of one hydrogen atom from the thiol group of an alkylthiol), cycloalkyl (by removal of a hydrogen atom from a cycloalkane), cycloheteroalkyl (by removal of a hydrogen atom from a cycloheteroalkane), aryl (by removal of a hydrogen atom from an aromatic ring of the aromatic hydrocarbon), heteroaryl (by removal of a hydrogen atom from any ring atom), amino (by removal of one hydrogel atom from an amine), etc.

The term “divalent radical” refers to an organic radical that is obtained by removing two hydrogen atoms from an organic compound and that forms two bonds with other two groups in an organic compound. For example, an alkylene divalent radical (i.e., alkylenyl) is obtained by removal of two hydrogen atoms from an alkane, a cycloalkylene divalent radical (i.e., cycloalkylenyl) is obtained by removal of two hydrogen atoms from the cyclic ring.

In this application, the term “substituted” in reference to an alkyl or an alkylenyl means that the alkyl or the alkylenyl comprises at least one substituent which replaces one hydrogen atom of the alkyl or the alkylenyl and is selected from the group consisting of hydroxyl (-OH ), carboxyl (-COOH), -NH ₂ , sulfhydryl (-SH), C1 -C4 alkyl, C1 -C4 alkoxy, C1 -C4 alkylthio (alkyl sulfide), C1-C4 acylamino, C1 -C4 alkylamino, di-Ci-C4 alkylamino, and combinations thereof.

The term “terminal ethylenically-unsaturated group” refers to one ethylenically- unsaturated group at one of the two ends of the main chain (or backbone) of an organic compound as known to a person skilled in the art.

A “blending vinylic monomer” refers to a vinylic monomer capable of dissolving both hydrophilic and hydrophobic components of a polymerizable composition to form a solution.

A free radical initiator can be either a photoinitiator or a thermal initiator. A “photoinitiator” refers to a chemical that initiates free radical crosslinking/polymerizing reaction by the use of light. A “thermal initiator” refers to a chemical that initiates radical crosslinking/polymerizing reaction by the use of heat energy.

“Post-curing surface treatment”, in reference to a silicone hydrogel bulk material or a SiHy contact lens, means a surface treatment process that is performed after the silicone hydrogel bulk material or the SiHy contact lens is formed by curing (i.e., thermally or actinically polymerizing) a SiHy lens formulation.

The term “silicone hydrogel lens formulation” or “SiHy lens formulation” interchangeably refers to a polymerizable composition that comprises all necessary polymerizable components for producing a silicone hydrogel (SiHy) contact lens or a SiHy lens bulk material as well known to a person skilled in the art.

In general, the invention is directed to a class of photochromic polydiorganosiloxane vinylic crosslinkers which each comprise (1) a polydiorganosiloxane polymer chain comprising dimethylsiloxane units and photochromic siloxane unit having one methyl substituent and one organic substituent having a photochromic moiety; (2) two terminal ethylenically-unsaturated groups.

There are several potential unique features associated with use of hydrophilized polydiorganosiloxane vinylic crosslinkers of the invention in making photochromic contact lenses, especially photochromic silicone hydrogel contact lenses. First, a photochromic polydiorganosiloxane vinylic crosslinker of the invention is more compatible with other polymerizable components in a typical polymerizable composition (i.e., a lens formulation) for making contact lenses, because very bulky and hydrophobic photochromic moieties are incorporated as one of the two substituents of each photochromic siloxane unit in a polydiorganosiloxane vinylic crosslinker. It is suitable for preparing various solvent-containing or solventless lens formulations.

Second, a photochromic polydiorganosiloxane vinylic crosslinker of the invention can have dual functions as a lens-forming material. Because a photochromic polydiorganosiloxane vinylic crosslinker of the invention is still a polydiorganosiloxane comprising dimethylsiloxane units, it can provide a relatively high oxygen permeability to resultant contact lenses, like other polydimethylsiloxane vinylic crosslinkers currently used in making silicone hydrogel contact lenses. It is believed that in order to achieve a higher oxygen permeabily, a polydiorganosiloxane should have at least 5 dimethylsiloxane units in a consecutive sequence. By controlling ratio of photochromic siloxane units over dimethylsiloxane units in a photochromic polydiorganosiloxane vinylic crosslinker of the invention to be sufficient low, one can ensure that a resultant polydiorganosiloxane vinylic crosslinker can have sufficient siloxane segments consisting of more than 5 consecuive dimethylsiloxane units. Such a polydiorganosiloxane vinylic crosslinker may be used to efficiently provide relatively-high oxygen permeability per siloxane unit without adversely affecting its compatibility with other polymerizable components. Furthermore, because a photochromic polydiorganosiloxane vinylic crosslinker of the invention comprises photochromic moieties capable of undergoing a reversible color change upon exposure to UV- or FIEVL-irradiation, it can also provide photochromic capability/property to resultant silicone hydrogel contact lenses.

Third, by using a photochromic polydiorganosiloxane vinylic crosslinker of the invention in a silicone hydrogel lens formulation, silicone hydrogel contact lenses obtained from the lens formulation can have a long-lasting photochromic property, because photochromic moieties are integral parts of polydiorganosiloxanes and located in hydrophobic microscopic regions (i.e., microscopic silicone regions) in a silicone hydrogel contact lens. By avoiding or minimizing exposure to water of stable backbones, the photochromic moieties would be less susceptible to hydrolysis. The resultant silicone hydrogel contact lenses could have a long-lasting photochromic property.

Fourth, by using a photochromic polydiorganosiloxane vinylic crosslinker of the invention in a silicone hydrogel lens formulation, silicone hydrogel contact lenses obtained from the lens formulation can have improve activation and deactivation rate. Besides the impact from their structures, the activation and deactivation rates of photochromates are closely related to their microenvironment as well. Photochromate activation is a ring-opening process, which is a volume expanding process, therefore steric hindrance plays a very important role in it. Polydiorganosiloxane chain has very good flexibility. Photochromates surrounded by polydiorganosiloxane chains would have significantly reduced energy barrier to overcome to be activated. From reaction activation energy point of view, same rational is applicable to the reversal process, therefore deactivate rate would improve as well.

The present invention, in one aspect, provides a photochromic polydiorganosiloxane vinylic crosslinker. The photochromic polydiorganosiloxane vinylic crosslinker of the invention comprises: (1) a polydiorganosiloxane segment comprising dimethylsiloxane units and at least one photochromic siloxane unit having one methyl substituent and one photochromic organic substituent having at least one photochromic moiety, and (2) two terminal ethylenically-unsaturated groups (preferably (meth)acryloyl groups).

In a preferred embodiment, the polydiorganosiloxane segment comprises from 3 to 500 (preferably from 5 to 450, more preferably from 10 to 400, even more preferably from 20 to 350) dimethylsiloxane units and from 1 to 80 (preferably from 2 to 70, more preferably from 3 to 60, even more preferably from 3 to 50) photochromic siloxane units.

In a preferred embodiment, the molar ratio of the photochromic siloxane units to the dimethylsiloxane units is from about 0.002 to about 0.50 (preferably from about 0.002 to about 0.20, more preferably from about about 0.004 to about 0.1 , even more preferably from about 0.004 to about 0.05).

In another preferred embodiment, a photochromic polydiorganosiloxane vinylic crosslinker of the invention can have a number average molecular weight of at least 1000 Daltons (preferably from 1500 Daltons to 80000 Daltons, more preferably from 2000 to 50000 Daltons, even more preferably from 2500 to 25000 Dalton).

In accordance with the invention, the photochromic polydiorganosiloxane vinylic crosslinker is preferably defined by formula (1) in which: u1 is an integer of from 3 to 500 (preferably from 5 to 450, more preferably from

10 to 400, even more preferably from 20 to 350) and col is an integer of from 1 to

80 (preferably from 2 to 70, more preferably from 3 to 60, even more preferably from 3 to 50),

Ei is a monovalent radical of

Ro is hydrogen or methyl; a1 is zero or 1 ;

Xo is O or NRNI ; R _N1 is hydrogen or a C ₁ -C ₁₅ alkyl;

Lo is a C2-C8 alkylene divalent radical or a divalent radical of

Lo’ is a C2-C8 alkylene divalent radical which has zero or one hydroxyl group; Lo” is C3-C8 alkylene divalent radical which has zero or one hydroxyl group; Xi is -0-, -NR _N1 - -NHCOO-, -OCONH- -CONR _N1 - or -NR _N1 CO-;

Xi’ is O or NR _N1 ; q1 is an integer of 1 to 20; q2 is an integer of 0 to 20; a2 is zero or 1 ; a3 is zero or an integer of from 1 to 3;

R1 is a linear or branched C1-C10 alkylene divalent radical;

R ₂ is a linear or branched C ₃ -C ₁₀ alkylene divalent radical;

R3 is a direct bond or a linear or branched C1-C4 alkylene divalent radical; XPC and each X ₂ independently of others are a covalent linkage of -0-, -S-

R _N 2 is hydrogen, a linear or branched C1-C15 alkyl, cyclohexyl, cyclopentyl, a substituted or unsubstituted phenyl, or a substituted- or unsubstituted-phenyl-Cr C ₆ alkyl; each L _x independently is a linear or branched C1-C24 alkylene divalent radical which optionally has one or more hydroxyl or C ₁ -C ₄ -alkoxy groups or C1-C4- acylamino groups , or a divalent radical which optionally has one or more hydroxyl or CrC4-alkoxy groups and is obtained by removal of two hydrogen atoms from two different atoms of a hydrocarbon that has up to 20 carbon atoms and comprises at least one divalent radical selected from the group consisting of cycloalkylene radical, substituted cycloalkylene radical, phenylene radical, susbtituted phenylene radical, cycloheteroalkylene radical, and substituted cycloheteroalkylene radical; each R , R5 and R ₆ independent of one another are a linear or branched C1-C15 alkylene divalent radical which has zero or one hydroxyl group; and PC is a photochromic group.

In a preferred embodiment, in formula (1) a1 is zero and then Ei is a monovalent radical

In another preferred embodiment, is from about 0.002 to about 0.50 (preferably from about 0.002 to about 0.20, more preferably from about about 0.004 to about 0.1 , even more preferably from about 0.004 to about 0.05).

In another preferred embodiment, the photochromic group (PC group) is a monovalent organic radical that has one colorless or light-colored form and one colored form and can undergo reversible change from the colorless or light-colored form to the colored form upon exposure to UV-irradiation or HEV light and that is derived directly from a reactive photochromic compound that has a reactive functional group, designated as “Epc”, selected from the group consisting of wherein the E _PC has participated in a coupling reaction with a co-reactive functional group to form a covalent linkage of Xpc.

A photochromic polydiorganosiloxane vinylic crosslinker of formula (1) can be prepared in a two-step process.

In the first step, a hydrosiloxane-containing polydiorganosiloxane of formula (2) is reacted with an ene monomer containing a reactive functional group () in a platinum- catalyzed hydrosilylation reaction as known to a person skilled in the art, to form a polydiorganosiloxane vinylic crosslinker having pendant reactive functional groups as represented by formula (3) in which are as defined above for formula (1) and E _e is a first reactive functional group selected from the group consisting of

Hydrosiloxane-containing polydiorganosiloxane of formula (2) can be prepared according to any methods known to a person skilled in the art. As an illustrative example, a hydrosiloxane-containing polydiorganosiloxane of formula (2) can be prepared from polymerization of a mixture of octamethylcyclotetrasiloxane (D4) and 1 ,3,5,7- tetramethylcyclotetrasiloxane (H4) in presence of 1 ,3-bis(E1 group)-terminated tetramethyldisiloxane (e.g., 1 ,3-bis[3-(meth)acryloxypropyl] tetramethyldisiloxane, 1 ,3- bis[3-(meth)acrylamidopropyl] tetramethyldisiloxane, or the like) as a chain end block and in the presence of a catalyst. By controlling the molar ratio of D4 to H4, a desired value of u1/w1 can be obtained. It is understood that 1 ,3-bis(E1 group)-terminated tetramethyldisiloxane can be prepared from 1 ,3-bis(hydroxyalkyl)tetramethyldisloxane (e.g., 1 ,3-bis(hydroxypropyl)tetramethyldisloxane) or 1 ,3- bis(aminoalkyl)tetramethyldisloxane (e.g., 1 ,3-bis(aminopropyl)tetramethyldisloxane).

Any ene monomers can be used in preparing a polydiorganosiloxane vinylic crosslinker of formula (3), so long as the ene monomers comprise a reactive functional group Various ene monomers having a reactive functional groups can be obtained from commercial suppliers or prepared according to known methods.

Examples of commercially available carboxyl-containing ene monomers include without limitation 3-butenoic acid, 4-pentenoic acid, 5-hexenoic acid, and 6-heptenoic acid. 2,2-dimethyl-4-pentanoic acid, 2-methyl-4-pentanoic acid, 2-propyl-4-pentanoic acid, 3-methyl-4-pentanoic acid, 4-vinylcyclohexanecarboxylic acid, 2-[4-(4- pentenyl)cyclohexyl] acetic acid, 4-propenylcyclohexanecarboxylic acid, 3-[2-(2- propenyl)cyclohexyl]propanoic acid, 2-(4-ethyenylcyclohexyl)acetic acid, 4-[4-(2- propenyl)cyclohexyl]butanoic acid, 2-ethenylcyclohexabe-1 -carboxylic acid, 2-, 3- or 4- vinylbenzoic acid, 4-(2-propenyl)benzoic acid, 2-allylbenzoic acid, (4-vinylphenyl)acetic acid, and 2-methyl-2-(4-vinylphenyl)propanoic acid.

Examples of commercially available ene monomers having a primary or secondary amino group include without limitation allylamine, 3-butenylamine, 4- pentenylamine, 1 ,1-dimethylallylamine, 1 -methyl-4-pentenylamine, 5-hexenylamine, 5- heptenylamine, 6-heptenylamine, N-ethyl-2-methylallylamine, N-ethylallylamine, N- allylmethylamine, N-allyl-1-pentanamine, N-allyl-2-methyl-1 -pentanamine, N-Allyl-2,3- dimethyl-1-pentanamine, N-allyl-1-hexanamine, N-allyl-2-methyl-1-hexanamine, N-allyl-1 - octanamine, N-allyl-1-ecanamine, N-allyl-1-dodecanamine, N-allyl-1 -heptanamine, N- allyl-ethylenediamine, N-allyl-cyclo-hexanamine, N-3-butenylcyclohexanamine, N-4- pentenylcyclohexanamine, N-5-hexenyl-cyclohexanamine, 1 -amino-4-vinyl-cyclohexane, 1-allyl-2,5-dimethylpiperazine, 1 -ally-piperazine, 4-vinylaniline, N-allylaniline, N-allyl- benzylamine, N-ally-a-methylbenzylaniline, 4-vinylpiperidine, 3-vinylpiperidine, 2- allylpyrrolidine, 3-vinylpyrrolidine, etc.

Examples of commercially available ene monomers having an isocyanato group include without limitation allyl isocyanate, 4-isocyanato-1 -butene, 3-isocyanate-2-methyl- propene, 3-isocyanate-1 -butene, 3-isocyanate-3-methyl-1 -butene, 3-isocyanate-2,3- dimethyl-1 -butene, 4-isocyanate-2-methyl-1 -butene, 4-isocyanate-3, 3-dimethyl- 1 -butene, 3-isocyanate-3-methyl-1 -pentene, 4-isocyanate-4-methyl-1 -pentene, 5-isocyanate-1 - pentene, 3-isocyanate-1 -hexene, 3-isocyanate-5,5-dimethyl-1 -hexene, 1-isocyanate-2- heptene, etc.

Examples of commercially available hydroxyl-containing ene monomers include without limitation allyl alcohol, 2-methyl-2-propen-1 -ol, 3-buten-1 -ol, 3-buten-2-ol, 3- methyl-3-buten-1-ol, 2-methyl-3-buten-2-ol, 2-methyl-3-buten-1 -ol, 1-penten-3-ol, 4- penten-1-ol, 4-penten-2-ol, 1-hexen-3-ol, 5-hexen-1-ol, 5-hexen-2-ol, 3-methyl-1-hexen-3- ol, 5-methyl-1 -hexen-3-ol, 1-hepten-3-ol, allyloxyethanol, di(ethylene glycol) monoallyl ether, polyethylene glycol) monoallyl ether, poly(propylen glycol) monoallyl ether, allyloxypropanol, 1-allyloxy-2-propanol, 4-allyloxy-1 -butanol, 1 -vinyl cyclohexanol, 2-vinyl cyclohexanol, 4-vinylcyclohexanol, 1-allylcycloheanol, 2-allycyclohexanol, 4- allylcyclohexanol, 4-vinylphenol, (4-vinylphenyl)methanol, (4-vinylphenyl)ethanol, 3-(4- Vinylphenyl)-1 -propanol, 1 -(4-Vinylphenyl)-2-methyl-2-propanol, etc.

Examples of commercially available thiol-containing ene monomers include without limitation allyl mercaptan, 3-butene-1 -thiol, 3-methyl-3-butene-1 -thiol, 2-methyl-3- butene-1 -thiol, 2-methyl-3-butene-2-thiol, 4-pentene-1 -thiol, etc.

Examples of commercially available ene monomers having an aldehyde group include without limitation 3-butenal, 4-pentanal, 5-hexenal, 2,2-dimethyl-4-pentenal, 2- methyl-4-pentenal, etc.

Examples of commercially available epoxy-containing ene monomers include without limitation 3, 4-epoxy-1 -butene, 2-methyl-2-vinyloxirane, 3,4-epoxy-1-pentene, 4,5- epoxy-1-pentene, 1 ,2-epoxy-5-hexene, 1 ,2-epoxy-6-heptene, 1 ,2-epoxy-7-octene, 1 ,2- epoxy-8-nonene, 1 ,2-epoxy-9-decene, allyloxy glycidyl ether, and 2-methyl-2- vinyloxirane, 4-vinyl- 1-cyclohexen-1 ,2-epoxide, etc.

Examples of commercially available ene monomers having an aziridinyl group include without limitation 2-vinylaziridine, 1-allyaziridine, N-allyl-2-methylaziridine, etc.

All of the above described commercially-available ene monomers can be used in the invention. Alternatively, ene monomers having a reactive functional group can be prepared by reacting a compound having two ene groups with a mercaptane having a reactive functional group (e.g., hydroxyl, primary amino, secondary amino, carboxyl, or ketone group) based on thiol-ene “click” reaction as known in the art.

In the second step, a polydiorganosiloxane vinylic crosslinker of formula (3) is reacted with a photochromic compound having a second reactive functional group

(designated as “E _PC ”) selected from the group consisting of the absence or presence of a coupling agent (i.e., having two of the reactive functional groups listed above) under well known coupling reaction conditions, to form a photochromic polydiorganosiloxane vinylic crosslinker of formula (1).

Non-limiting examples of coupling reactions under various reaction conditions between a pair of matching co-reactive functional groups selected from the group preferably consisting of primary group, secondary amino group, hydroxyl group, carboxyl group, acid anhydride group, aldehyde group, isocyanate group, epoxy group, aziridine group, azlactone group and thiol group, are given below for illustrative purposes. A primary/secondary amino group reacts with aldehyde or ketone group to form a Schiff base which may further be reduced into an amine bond; a primary/secondary amino group -NHR (in which R is hydrogen or C1-C6 alkyl) reacts with an acid chloride or bromide group or with an acid anhydride group to form an amide linkage (-CO-NR- ); an amino group -NHR reacts with a N-hydroxysuccinimide ester group to form an amide linkage; an amino group -NHR reacts with a carboxylic acid group in the presence of a coupling agent - carbodiimide (e.g., 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), N,N’-dicyclohexylcarbodiimide (DCC), 1-cylcohexyl-3-(2- morpholinoethyl)carbodiimide, diisopropyl carbodiimide, or mixtures thereof) and N- hydroxysuccinimide to form an amide linkage; an amino group -NHR reacts (ring opening) with an azlactone group to form an alkylene-diamido linkage (-CONH-CT1T2- (CH ₂ )pi-CONH-); an amino group -NHR reacts with an isocyanate group to form a urea linkage (-NR-C(O)-NH- with R as defined above); an amino group -NHR reacts with an epoxy or aziridine group to form an amine bond (-C-NR-); a hydroxyl reacts with an isocyanate to form a urethane linkage; a hydroxyl reacts with an epoxy or aziridine to form an ether linkage (-0-); a hydroxyl reacts with an acid chloride or bromide group or with an acid anhydride group to form an ester linkage; a carboxyl group reacts with an epoxy group to form an ester bond; a thiol group (-SH) reacts with an isocyanate to form a thiocarbamate linkage (-N-C(O)-S-); a thiol group reacts with an epoxy or aziridine to form a thioether linkage (-S-); a thiol group reacts with an acid chloride or bromide group or with an acid anhydride group to form a thioester linkage; a thiol group reacts with an azlactone group in the presence of a catalyst to form a linkage (-CONH-CT _I T ₂ -(CH ₂ ) _PI - CO-S-); a thiol group reacts with an ene group or vinylsulfonyl group based on thiol-ene “click” reaction under thiol-ene reaction conditions to form a thioether linakge (-S-); a thiol group reacts with a (meth)acryloyl group based on Michael Addition under appropriate reaction conditions to form a thioether linkage.

The reactions conditions for the above described coupling reactions are taught in textbooks and are well known to a person skilled in the art.

In accordance with the invention, coupling agents, each of which has two reactive functional groups, may be used in the coupling reactions. A coupling agent having two reactive functional groups can be: a diisocyanate compound; a di-acid halide compound; a di-carboxylic acid compound; a di-carboxylic acid anhydride compound; a diamine compound; a diol compound; a di-epoxy compound; a di-aziridine compound; di- azlactone compound; a di-ene compound; a divinylsulfone compound; a di-thiol compound; a thiolactone compound; an amin oacid compound; a hydroxy-containing amine compound; an amine compound having one hydroxyl or ketone group; a hydroxy- containing carboxylic acid compound; a mercaptane having a hydroxyl, carboxyl or amino group.

For example, a diisocyanate, di-carboxylic acid (preferably a di-carboxylic acid anhydride), di-aziridine, di-epoxy, or di-azlactone compound can be used in the coupling of E _e and E _PC when they are different or same and are selected from the group consisting of hydroxyl, primary amino, secondary amino, and thiol groups; a di-amine, di-hydroxyl, di-thiol, hydroxy-containing amine, or hydroxy-containing thiol compound can be used in the coupling of E _e and E _PC when they are different or same and are selected from the group consisting of isocyanate, epoxy, aziridine, and carboxylic acid groups; a di-epoxy compound can be used in the coupling of E _e and E _PC when they both are carboxylic acid groups; a di-amine compound can be used in the coupling of E _e and E _PC when they both are aldehyde groups; a divinylsulfone compound can be used in the coupling of E _e and E _PC when they both are thiol groups; a thiolactone compound can be used to covalently attach a thiol group through a linkage to either of E _e and E _PC when it is a primary or secondary amino group; a mercaptane having a hydroxyl, carboxyl, amino, or ketone group can be used to covalently attach a hydroxyl, carboxyl, amino, or ketone group through a linkage to E _PC when it is an ene or (meth)acryloyl group. A person skilled in the art knows well how to select one or more coupling agents, based on selectivity and/or differential reactivity of a given functional group, to link E _e and E _PC to form a photochromic polydiorganosiloxane vinylic crosslinker of the invention.

Examples of commercially available di-carboxylic acid anhydrides include without limitation succinic acid anhydride, methylsuccinic anhydride, 2,2-dimethylsuccinic anhydride, 2,3-dimethylsuccinic acid, glutaric acid anhydride, 3,3-dimethylglutaric anhydride, 2,2-dimethylglutaric anhydride, 3-methylglutaric anhydride, 3,3- tetramethylglutaric anhydride, diglycolic anhydride, adipic anhydride, etc.

Any suitable C3-C24 di-carboxylic acid compounds can be used in the invention. Examples of preferred di-carboxylic acid compounds include without limitation a linear or branched C3-C24 aliphatic dicarboxylic acid, a C5-C24 cycloaliphatic or aliphatic- cycloaliphatic dicarboxylic acid, a C6-C24 aromatic or araliphatic dicarboxylic acid, a dicarboxylic acid which contains amino or imido groups or N-heterocyclic rings, and combinations thereof. Examples of suitable aliphatic dicarboxylic acids are: oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, dimethylmalonic acid, octadecylsuccinic acid, trimethyladipic acid, and dimeric acids (dimerisation products of unsaturated aliphatic carboxylic acids, such as oleic acid). Examples of suitable cycloaliphatic dicarboxylic acids are: 1 ,3-cyclobutanedicarboxylic acid, 1 ,3- cyclopentanedicarboxylic acid, 1 ,3- and 1 ,4-cyclohexanedicarboxylic acid, 1 ,3- and 1 ,4- dicarboxylmethylcyclohexane, 4,4'-dicyclohexyldicarboxylic acid. Examples of suitable aromatic dicarboxylic acids are: terephthalic acid, isophthalic acid, o-phthalic acid, 1 ,3-, 1 ,4-, 2,6- or 2,7-naphthalenedicarboxylic acids, 4,4'-biphenyldicarboxylic acid, 2,2'- biphenyldicarboxylic acid, 4,4'-diphenylsulphone-dicarboxylic acid, 1 ,1 ,3-trimethyl-5- carboxyl-3-(p-carboxyphenyl)-indane, 4,4'-diphenyl ether-dicarboxylic acid, bis-p- (carboxylphenyl)-methane.

Any suitable diacid halides can be used in the invention. Examples of preferred diacid halide include without limitations fumaryl chloride, suberoyl chloride, succinyl chloride, phthaloyl chloride, isophthaloyl chloride, terephthaloyl chloride, sebacoyl chloride, adipoyl chloride, trimethyladipoyl chloride, azelaoyl chloride, dodecanedioic acid chloride, succinic chloride, glutaric chloride, oxalyl chloride, dimer acid chloride, and combinations thereof.

Any suitable diamines can be used in the invention. An organic diamine can be a linear or branched C2-C24 aliphatic diamine, a C5-C24 cycloaliphatic or aliphatic- cycloaliphatic diamine, or a C6-C24 aromatic or alkyl-aromatic diamine. A preferred organic diamine is N,N'-bis(hydroxyethyl)ethylenediamine, N,N'-dimethylethylenediamine, ethylenediamine, N,N'-dimethyl-1 ,3-propanediamine, N,N'-diethyl-1 ,3-propanediamine, N- methyl-1 ,3-diaminopropane, N-methylethylenediamine, N-ethylethylenediamine, N- isopropyl-1 ,3-propanediamine, N-propyl-1 ,3-propanediamine, N-butylethylenediamine,

2.2-dimethyl-1 ,3-propanediamine, 1 ,4-butanediamine, 1 ,5-pentanediamine, hexamethylenediamine, 2-Methyl-1 ,5-pentanediamine, 1 ,6-hexamethylenediamine, N,N'- dimethyl-1 ,6-hexamethylenediamine, 2,2,4(2,4,4)-trimethyl-1 ,6-hexanediamine, 1 ,3- diamino-2-propanol, 1 ,2-diaminoethane-1 ,2-diol, 1 ,1-diaminoethane-1 ,2-diol, 1 ,4-diamino-

2.3-butanediol, 1 ,3-cyclopentanediamine, 1 ,4-diaminocyclohexane, 1 ,3- Bis(aminomethyl)cyclohexane, 4,4'-diaminodicyclohexylmethane, 4,4'-methylenebis(2- methylcyclohexylamine), isophorone diamine (3-aminomethyl-3,5,5- trimethylcyclohexylamine), m-xylylene diamine, p-xylylene diamine, piperazine, 1-(2- aminoethyl)piperazine, 1 ,4-bis(3-aminopropyl)piperazine, 2-piperazinoethylamine, 1-Boc- piperazine, 4-(2-aminoethyl)-1-Boc-piperazine, 1-(2-/V-Boc-aminoethyl)piperazine, 4-(2- aminoethyl)-1-Boc-piperazine, 4-aminopiperidine, 3-aminopiperidine, 4- aminomethylpiperidine, 2-aminomethylpiperidine, 1-Boc-piperidine-4-carboxaldehyde, 1- Boc-piperidine-4-acetaldehyde, etc.

Any suitable C4-C24 diisocyanates can be used in the invention. Examples of preferred diisocyanates include without limitation tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, heptamethylene diisocyanate, 1 ,6-diisocyanato-2,2,4-trimethylhexane, octamethylene diisocyanate, dodecamethylene diisocyanate, cyclohexane diisocyanate, 1 ,3-bis-(4,4'- isocyantomethyl)cyclohexane, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, toluene diisocyanate, 4,4'-diphenyl diisocyanate, 4,4'-diphenylmethane diisocyanate, p-phenylene diisocyanate, etc.

Any suitable di-epoxy compounds can be used in the invention. Examples of preferred di-epoxy compounds are neopentyl glycol diglycidyl ether, 1 ,3-butadiene diepoxide, 1 ,4-butanediol diglycidyl ether, 1 ,2,7,8-diepoxyoctane, 3,4- epoxycyclohexylmethyl-3, 4-epoxycyclohexane, 3,4-epoxycyclohexylmethyl-3,4- epoxycyclohexane carboxylate, vinylcyclohexene dioxide, 1 ,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, bis[4-(glycidyloxy)phenyl]methane, Bisphenol A diglycidyl ether (2,2-Bis[4-(glycidyloxy)phenyl]propane), Bisphenol A propoxylate diglycidyl ether, and combinations thereof.

Any suitable C2-C24 diols (i.e., compounds with two hydroxyl groups) can be used in the invention. Examples of preferred diols include without limitation ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, 1 ,4-butanediol, various pentanediols, various hexanediols, various cyclohexanediols, 1 ,4-bis(2-hydroxyethyl)piperazine, and combination thereof.

Any dimercaptans having 2 to 24 carbon atoms can be used in the invention to prepare a prepolymer of the invention. Examples of dimercaptans include without limitation C2-C12 alkyl dimercaptans (e.g., ethyl dimercaptan, propyl dimercaptan, butyl dimercaptan, pentamethylen dimercaptan, hexamethylene dimercaptan, heptamethylene dimercaptan, octamethylen dimercaptan, nonamethylene dimercaptan, decamethylene dimercaptan, 3-ethylcyclohexane-1 ,2-dithiol, 3-(2-sulfanylethyl)cyclohexane-1 -thiol, 3-(1- sulfanylethyl)cyclohexane-1 -thiol, 2-methyl-5-(2-sulfanylpropyl)cyclohexane-1 -thiol, 2- propylcyclohexane-1 ,4-dithiol, benzenedithiol, methyl-substituted benzenedithiol, benzenedimethanethiol, 1 ,1 -biphenyl-4, 4’-dimethanethiol, biphenyl-4, 4-dithiol, ethyl ether dimercaptan, triglycol dimercaptan, tetraglycol dimercaptan, dimercaprol, 2,3- dimercaptopropanol, dithiothreitol, etc.

Any amino acids can be used in the invention. Examples of amino acids include without limitation glycine, proline, alanine, valine, isoleucine, leucine, 2-aminoisobutyric acid, 4-aminobutyric acid, 3-aminoisobutyyric acid, 3-amino-butyric acid, b-alanine, 1- amino-3-cyclopentane carboxylic acid, 3-aminocyclohexanecarboxylic acid, pyrrolidine-3- carboxylic acid, 4-piperidinecarboxylic acid, 3-piperidinecarboxylic acid, 1 - piperazineacetic acid, etc.

Examples of compounds having one amino group and one hydroxyl or aldehyde group (or ketone group) include without limitation 1-piperazinepropanol, 2-[2-(1- piperazinyl)ethoxy]ethanol, 4-amino-1-piperazineethanol, 4-piperidinemethanol, 1-Boc- piperidine-4-carboxaldehyde, 4-formylpiperidine, N-Boc-4-piperidineacetaldehyde, etc.

Examples of preferred commercially-available thiolactone include without limitation 4-butyrothiolactone (or dihydro-2(3H)-thiophenone), 3-methyldihydro-2(3H)- thiophenone, 3-ethyldihydro-2(3H)-thiophenone, 3-(1 -methylethyl)dihydro-2(3H)- thiophenone, 3,3-dimethyldihydro-2(3H)-thiophenone, 3-ethyl-3-methyldihydro-2(3H)- thiophenone, 3-acetyldihydro-2(3H)-thiophenone, N-acetyl homocysteine thiolactone, N- propionyl homocysteine thiolactone, N-butyryl homocysteine thiolactone, and N- carboxybutyryl homocysteine thiolactone (or 4-oxo-4-[(tetrahydro-2-oxo-3-thienyl)amino]- butanoic acid).

Any divinylsulfone compounds can be used in the invention. Examples of preferred divinylsulfone compounds include without limitation divinyl sulfone, bis(vinylsulfonyl) C1-C6 alkane, 1 ,3-bis(vinylsulfonyl)-2-propanol, 1 ,1 -bis(vinylsulfonyl)-1 - propanol, 1 ,5-bis(vinylsulfonyl)-3-pentanol, 1 ,1-bis(vinylsulfonyl)-3-methoxypropane, 1 ,5- bis(vinylsulfonyl)-2,4-dimethylbenzene, and 1 ,4-bis(vinylsulfonyl)-2, 3,5,6- tetrafluorobenzene.

Examples of preferred primary and secondary amino-containing chain transfer agents include without limitation 2-mercaptoethylamine, 2-mercaptopropylamine, 3- mercaptopropylamine, 2-mercaptobutylamine, 3-mercaptobutylamine, 4- mercaptobutylamine, 5-mercaptopentylamine, 6-mercaptohexylamine, N- methylaminoethanethiol, N-ethylaminoethanethiol, N-methylaminopropanethiol, N- ethylaminopropanethiol, N-methylaminobutanethiol, N-ethylaminobutanethiol, 2- aminothiolphenol, 3-aminothiolphenol, 4-aminothiolphenol, etc.

Examples of mercaptanes having a carboxylic group include without limitation thioglycolic acid, 2-mercaptopropinic acid, 3-mercaptopropionic acid, 4-mercaptobutyric acid, 2-methyl-3-sulfanylpropanoic acid, 2-mercaptoisobutyric acid, 6-mercaptohexanoic acid, 8-marcaptooctanoic acid, 4-mercaptobenzoic acid, 3-mercaptobenzoic acid, 4- mercaptophenylacetic acid, 2-mercapto-2-phenylacetic acid, etc.

Examples of preferred hydroxyl-containing mercaptanes includes without limitation 2-mercaptoethanol, 3-mercaptonpropanol, 1-mercapto-2-propanol, 2-mercapto-1- propanol, 4-mercapto-1 -butanol, 2-mercapto-3-butanol, 3-mercapto-3-methyl-1 -butanol, 4-mercapto-4-methyl-1 -pentanol, 4-mercapto-4-methyl-2-pentanol, 6-mercapto-1 - hexanol, 3-mercapto-1-hexanol, 8-marcapto-1-octanol, 9-mercapto-1-nonanol, 2- mercaptophenol, 3-mercaptophenol, 4-mercaptophenol, 2-mercaptobenzyl alcohol, 4-(6- mercaptohexyloxy)benzyl alcohol, etc.

Examples of preferred mercaptanes having methylcarbonyl group (-COCH3) include without limitation 4-methyl-4-mercaptopentan-2-one, 3-mercapto-2-butanone, etc.

It is desirable to increase the length of covalent linkage between one first reactive functional group E _e and the second functional group E _PC of the photochromic compound and/or convert one of E _e and E _PC to a different reactive functional group that will react with the other group (e.g., in cases where a3 is an integer of from 1 to 3 in formula (1) above) by using one or more coupling agents (i.e., any one of those described above or the likes).

Any photochromic compounds can be used to prepare a photochromic polydiorganosiloxane vinylic crosslinker of the invention, so long as they contain a reactive functional group, such as, a hydroxyl group, a carboxyl group, a primary amino group, a secondary amino group, an isocyanato group, an epoxy group, an aziridine group, a thiol group, a ketone group, or an ethylenically unsaturated group (e.g., ene group, vinyl, vinylsulfonyl group, acryloyl group, and methacryloyl group).

Various reactive photochromic compounds are disclosed in the patents and can be obtained from commercial sources or prepared by following the procedures described in the patents and literatures. Examples of preferred reactive photochromic compounds, from which photochromic groups of a polydiorganosiloxane vinylic crosslinker of the invention are derived, include without limitation naphthopyrans, indeno-fused naphthopyrans (i.e., indeno-naphthopyrans), heterocyclic ring-fused naphthopyrians, benzopyrans, phenanthropyrans, quinopyrans, quinolinopyrans, fluoroanthenopyrans, anthracene-fused pyrans, tetracene-fused pyrans, spiro(benzindoline)naphthopyrans, spiro(indoline)naphthopyrans, spiro(indoline)benzopyrans, spiro(indoline)quinopyrans, spiro(indoline)pyrans, naphthoxazines, spirobenzopyrans, spirobenzothiopyrans, naphthacenediones, benzoxazines, spirooxazines, naphthoxazines, spiro(benzindoline)naphthoxazines, spiro(indoline)naphthoxazines, spiro(indoline)pyrido- benzoxazines, spiro(indoline) benzoxazines, spiro(benzindoline)benzoxazines, spiro(benzindoline)pyridobenzoxazines, spiro(indoline)fluoranthenoxazines, spiro(indoline)-quinoxazines, spiropiperidine-naphthopyrans, piro(indoline)pyronobenzoxazinones, benzospiropyrans, naphthospiropyrans, spirobenzoxazine-pyrrolopyridines, spironaphthoxazine-pyrrolopyrridines, spiro-oxazepin- benzoxazines, spiro-oxazepin-naphthoxazines, spiro(indoline)benzothiazoloxazines, spiro(indoline)benzopyrroloxazines, spiro(indoline)quinazolino-oxazines, spiro(indoline)- anthracenobenzoxazines, benzofurobenzopyrans, benzothienobenzopyrans, naphthofurobenzopyrans, benzopyrano-fusednaphthopyrans, spiro(isoindoline)- naphthoxazines, spiro(isoindoline)benzoxazines, etc. Such reactive photochromic compounds are disclosed in U.S. Pat. Nos. 3100778, 3562172, 3567605, 3578602, 3671543, 4215010, 4342668, 4440672, 4634767, 4636561 , 4637698, 4699473, 4719296, 4720547, 4772700, 4784474, 4785097, 4816584, 4818096, 4826977, 4831142, 4880667, 4929693, 4931219, 4931221 , 4959471 , 4980089, 4986934, 5055576, 5066818, 5110922, 5114621 , 5139707, 5166345, 5171636, 5180524, 5186867, 5200116, 5238931 , 5238981 , 5244602, 5274132; 5340857, 5369158, 5384077, 5395567, 5399687, 5405958, 5411679, 5429774, 5451344, 5458814; 5458815, 5464567, 5466398, 5514817; 5520853, 5552090, 5552091 , 5565147, 5573712; 5578252, 5585042, 5623005, 5637262, 5637709, 5645767; 5650098, 5651923, 5656206; 5658500, 5658501 , 5674432, 5698141 , 5723072, 5728758, 5730908, 5744070, 5759450, 5783116, 5801243, 5808063, 5811034, 5831090, 5833885, 5869658; 5879592, 5891368, 5955520; 5961892; 5981634, 5998520, 6004486, 6017121 , 6018059; 6019914, 6022495, 6022497; 6030555, 6034193, 6065836, 6106744, 6106744, 6107395, 6113814, 6146554; 6149841 , 6153126, 6221284, 6248264; 6296785, 6315928; 6342459; 6348604, 6353102, 6414057, 6478988, 6630597, 7556750, 7584630, 7999989, 8158037, 8697770, 8698117, 8741188, 9029532, 9028728, 9052438, 9097916, 9465234, 9487499, 9904074, 10197707, 10501446, 10532997, and 10502998 and are also described in the texts, Techniques in Chemistry, Volume III. “Photochromism”, Chapter 3 (Glenn H. Brown, Editor, John Wiley and Sons, Inc., New York, 1971) and in “Chromic Phenomena: Technological Applications of Colour Chemistry” (P. Bamfield, RSC Books (2001)). Derivatives of these compounds that include various Substituents can be Synthesized from this teaching by people skilled in the art.

It is understood that a reactive photochromic compound can also be obtained by reacting a mercaptane having a reactive functional group (any one of those described above) with a polymerizable photochromic compound (i.e., one having an ethylenically unsaturated group) according to Michael-Addition reaction. Examples of preferred photochromic vinylic monomers include polymerizable naphthopyrans, polymerizable benzopyrans, polymerizable indenonaphthopyrans, polymerizable phenanthropyrans, polymerizable spiro(benzindoline)-naphthopyrans, polymerizable spiro(indoline)benzopyrans, polymerizable spiro(indoline)-naphthopyrans, polymerizable spiro(indoline)quinopyrans, polymerizable spiro(indoline)-pyrans, polymerizable naphthoxazines, polymerizable spirobenzopyrans; polymerizable spirobenzopyrans, polymerizable spirobenzothiopyrans, polymerizable naphthacenediones, polymerizable spirooxazines, polymerizable spiro(indoline)naphthoxazines, polymerizable spiro(indoline)pyridobenzoxazines, polymerizable spiro(benzindoline)pyridobenzoxazines, polymerizable spiro(benzindoline)naphthoxazines, polymerizable spiro(indoline)- benzoxazines, polymerizable diarylethenes, and combinations thereof, as disclosed in U.S. Pat. Nos. 4929693, 5166345 6017121 , 7556750, 7584630, 7999989, 8158037, 8697770, 8741188, 9052438, 9097916, 9465234, 9904074, 10197707, 6019914, 6113814, 6149841 , 6296785, and 6348604.

Examples of preferred reactive photochromic compounds without limitation include without limitation those compounds that are described later in this application and can be obtained from commercial suppliers or prepared according to procedures described in the patents discussed above and in the texts described above.

A photochromic polydiorganosiloxane vinylic crosslinker of the invention (formula (1) as defined above) can find particular use in preparing a polymer, preferably a silicone hydrogel polymeric material, which is another aspect of the invention. A person skilled in the art knows how to prepare a polymer or a silicone hydrogel polymeric material from a polymerizable composition according to any known polymerization mechanism.

In another aspect, the invention provides a soft photochromic contact lens comprising a crosslinked polymeric material comprising: units of a photochromic polydiorganosiloxane vinylic crosslinker of the invention (as described above).

In a preferred embodiment, the soft photochromic contact lens is a photochromic silicone hydrogel contact lens. Preferably, a photochromic silicone hydrogel contact lens of the invention, when being fully hydrated, has an oxygen permeability (Dk) of at least about 40 barrers (preferably at least about 60 barrers, more preferably at least about 70 barrers, even more preferably at least about 80 barrers), a water content of from about 15% to about 70% by weight (preferably from about 20% to about 70% by weight, more preferably from about 25% to about 65% by weight, even more preferably from about 30% to about 60% by weight), an elastic modulus of from about 0.20 MPa to about 1 .8 MPa (preferably from about 0.25 MPa to about 1.5 MPa, more preferably from about 0.3 MPa to about 1.2 MPa, even more preferably from about 0.4 MPa to about 1.0 MPa).

A person skilled in the art knows well how to measure the oxygen permeability, oxygen transmissibility, water content, and elastic modulus of silicone hydrogel contact lenses. These lens properties have been reported by all manufacturers for their silicone hydrogel contact lens products.

Various embodiments of a photochromic polydiorganosiloxane vinylic crosslinker of the invention (as defined above) should be incorporated into this aspect of the invention.

A photochromic silicone hydrogel contact lens of the invention also comprises units of at least one silicone-containing polymerizable component and units of at least one hydrophilic vinylic monomer.

In accordance with the invention, the silicone-containing polymerizable component other than a chromatic polydiorganosiloxane vinylic crosslinker of the invention can be a silicone-containing vinylic monomer, a polysiloxane vinylic crosslinker, one or more silicone-containing prepolymers, one or more polysiloxane vinylic crosslinkers, one or more silicone-containing prepolymers, or combinations thereof.

In accordance with the invention, a silicone-containing vinylic monomer can be any silicone-containing vinylic monomer known to a person skilled in the art. Examples of preferred silicone-containing vinylic monomers include without limitation vinylic monomers each having a bis(trialkylsilyloxy)alkylsilyl group or a tris(trialkylsilyloxy)silyl group, polysiloxane vinylic monomers, 3-methacryloxy propylpentamethyldisiloxane, t- butyldimethyl-siloxyethyl vinyl carbonate, trimethylsilylethyl vinyl carbonate, and trimethylsilylmethyl vinyl carbonate, and combinations thereof.

Preferred polysiloxanes vinylic monomers including those of formula (M1) are described later in this application and can be obtained from commercial suppliers (e.g., Shin-Etsu, Gelest, etc.); prepared according to procedures described in patents, e.g.,

U.S. Pat. Nos. 5070215, 6166236, 6867245, 8415405, 8475529, 8614261 , and 9217813; prepared by reacting a hydroxyalkyl (meth)acrylate or (meth)acrylamide or a (meth)acryloxypolyethylene glycol with a mono-epoxypropyloxypropyl-terminated polydimethylsiloxane; prepared by reacting glycidyl (meth)acrylate with a mono-carbinol- terminated polydimethylsiloxane, a mono-aminopropyl-terminated polydimethylsiloxane, or a mono-ethylaminopropyl-terminated polydimethylsiloxane; or prepared by reacting isocyanatoethyl (meth)acrylate with a mono-carbinol-terminated polydimethylsiloxane according to coupling reactions well known to a person skilled in the art.

Preferred silicone-containing vinylic monomers each having a bis(trialkylsilyloxy)alkylsilyl group or a tris(trialkylsilyloxy)silyl group, including those of formula (M2), are described later in this application and can be obtained from commercial suppliers (e.g., Shin-Etsu, Gelest, etc.) or can be prepared according to procedures described in U.S. Pat. Nos. 5070215, 6166236, 7214809, 8475529, 8658748, 9097840, 9103965, and 9475827.

Any suitable polysiloxane vinylic crosslinkers can be used in the invention. Examples of preferred polysiloxane vinylic crosslinkers are di-(meth)acryloyl-terminated polydimethylsiloxanes; di-vinyl carbonate-terminated polydimethylsiloxanes; di-vinyl carbamate-terminated polydimethylsiloxane; N,N,N',N'-tetrakis(3-methacryloxy-2- hydroxypropyl)-alpha,omega-bis-3-aminopropyl-polydimethylsil oxane; polysiloxane- containing macromer selected from the group consisting of Macromer A, Macromer B, Macromer C, and Macromer D described in US 5,760,100; polysiloxane-containing macromers disclosed in U.S. Pat. Nos. 4136250, 4153641 , 4182822, 4189546, 4343927, 4254248, 4355147, 4276402, 4327203, 4341889, 4486577, 4543398, 4605712,

4661575, 4684538, 4703097, 4833218, 4837289, 4954586, 4954587, 5010141 ,

5034461 , 5070170, 5079319, 5039761 , 5346946, 5358995, 5387632, 5416132,

5451617, 5486579, 5962548, 5981675, 6039913, and 6762264; polysiloxane-containing macromers disclosed in U.S. Pat. Nos. 4259467, 4260725, and 4261875.

One class of preferred polysiloxane vinylic crosslinkers are di-(meth)acryloyloxy- terminated polysiloxane vinylic crosslinkers each having dimethylsiloxane units and hydrophilized siloxane units each having one methyl substituent and one monovalent C4- C40 organic radical substituent having 2 to 6 hydroxyl groups, more preferably a polysiloxane vinylic crosslinker of formula (I), are described later in this application and can be prepared according to the procedures disclosed in U.S. Pat. No. 10081697.

Another class of preferred polysiloxane vinylic crosslinkers are vinylic crosslinkers each of which comprises one sole polydiorganosiloxane segment and two terminal (meth)acryloyl groups, which can be obtained from commercial suppliers; prepared by reacting glycidyl (meth)acrylate (meth)acryloyl chloride with a di-amino-terminated polydimethylsiloxane or a di-hydroxyl-terminated polydimethylsiloxane; prepared by reacting isocyantoethyl (meth)acrylate with di-hydroxyl-terminated polydimethylsiloxanes prepared by reacting an amino-containing acrylic monomer with di-carboxyl-terminated polydimethylsiloxane in the presence of a coupling agent (a carbodiimide); prepared by reacting a carboxyl-containing acrylic monomer with di-amino-terminated polydimethylsiloxane in the presence of a coupling agent (a carbodiimide); or prepared by reacting a hydroxyl-containing acrylic monomer with a di-hydroxy-terminated polydisiloxane in the presence of a diisocyanate or di-epoxy coupling agent.

Other classes of preferred polysiloxane vinylic crosslinkers are chain-extended polysiloxane vinylic crosslinkers each of which has at least two polydiorganosiloxane segments linked by a linker between each pair of polydiorganosiloxane segments and tweo terminal ethylenically unsaturated groups, which can be prepared according to the procedures described in U.S. Pat. Nos. 5034461 , 5416132, 5449729, 5760100, 7423074, 8529057, 8835525, 8993651 , 10301451 , and 10465047.

Any hydrophilic vinylic monomers can be used in the invention. Examples of preferred hydrophilic vinylic monomers are alkyl (meth)acrylamides (as described later in this application), hydroxyl-containing acrylic monomers (as described below), amino- containing acrylic monomers (as described later in this application), carboxyl-containing acrylic monomers (as described later in this application), N-vinyl amide monomers (as described later in this application), methylene-containing pyrrolidone monomers (i.e., pyrrolidone derivatives each having a methylene group connected to the pyrrolidone ring at 3- or 5- position) (as described later in this application), acrylic monomers having a Ci- C ₄ alkoxyethoxy group (as described later in this application), vinyl ether monomers (as described later in this application), allyl ether monomers (as described later in this application), phosphorylcholine-containing vinylic monomers(as described later in this application) , N-2-hydroxyethyl vinyl carbamate, N-carboxyvinyl^-alanine (VINAL), N- carboxyvinyl-a-alanine, and combinations thereof.

A photochromic silicone hydrogel contact lens of the invention can also further comprise units of at least one hydrophobic vinylic monomer, at least one non-silicone vinylic crosslinker, or combinations thereof.

In accordance with the invention, any hydrophobic vinylic monomers can be in this invention. Examples of preferred hydrophobic vinylic monomers include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, styrene, chloroprene, vinyl chloride, vinylidene chloride, (meth)acrylonitrile, 1 -butene, butadiene, vinyl toluene, vinyl ethyl ether, perfluorohexylethyl-thio-carbonyl-aminoethyl-methacrylate, isobornyl (meth)acrylate, trifluoroethyl (meth)acrylate, hexafluoro-isopropyl (meth)acrylate, hexafluorobutyl (meth)acrylate, and combinations thereof.

In accordance with the invention, any non-silicone vinylic crosslinkers can be in this invention. Examples of preferred non-silicone vinylic cross-linking agents are described later in this application.

In accordance with the invention, a photochromic silicone hydrogel (SiHy) contact lens of the invention can be produced according to any lens manufacturing processes. A person skilled in the art knows very well how to make SiHy contact lenses. For example, SiHy contact lenses can be produced in a conventional “spin-casting mold,” as described for example in US3408429, or by the full cast-molding process in a static form, as described in U.S. Pat. Nos. 4347198; 5508317; 5583463; 5789464; and 5849810, or by lathe cutting of polymeric material buttons as used in making customized contact lenses. In cast-molding, a polymerizable composition (i.e., a SiHy lens formulation) typically is dispensed into molds and cured (i.e., polymerized and/or crosslinked) in molds for making SiHy contact lenses.

Lens molds for making contact lenses including SiHy contact lenses are well known to a person skilled in the art and, for example, are employed in cast molding or spin casting. For example, a mold (for cast molding) generally comprises at least two mold sections (or portions) or mold halves, i.e. first and second mold halves. The first mold half defines a first molding (or optical) surface and the second mold half defines a second molding (or optical) surface. The first and second mold halves are configured to receive each other such that a lens forming cavity is formed between the first molding surface and the second molding surface. The molding surface of a mold half is the cavity forming surface of the mold and in direct contact with the polymerizable composition.

Methods of manufacturing mold sections for cast-molding a contact lens are generally well known to those of ordinary skill in the art. The process of the present invention is not limited to any particular method of forming a mold. In fact, any method of forming a mold can be used in the present invention. The first and second mold halves can be formed through various techniques, such as injection molding or lathing.

Examples of suitable processes for forming the mold halves are disclosed in U.S. Pat.

Nos. 4444711 ; 4460534; 5843346; and 5894002.

Virtually all materials known in the art for making molds can be used to make molds for making contact lenses. For example, polymeric materials, such as polyethylene, polypropylene, polystyrene, PMMA, Topas ^® COC grade 8007-S10 (clear amorphous copolymer of ethylene and norbornene, from Ticona GmbH of Frankfurt, Germany and Summit, New Jersey), or the like can be used. Other materials that allow UV light transmission could be used, such as quartz glass and sapphire.

In a preferred embodiment, reusable molds are used and the lens-forming composition is cured actinically under a spatial limitation of actinic radiation to form a contact lens. Examples of preferred reusable molds are those disclosed in U.S. Pat. Nos. 6627124, 6800225, 7384590, and 7387759. Reusable molds can be made of quartz, glass, sapphire, CaF ₂ , a cyclic olefin copolymer (e.g., Topas ^® COC grade 8007-S10 (clear amorphous copolymer of ethylene and norbornene) from Ticona GmbH of Frankfurt, Germany and Summit, New Jersey, Zeonex® and Zeonor® from Zeon Chemicals LP, Louisville, KY), polymethylmethacrylate (PMMA), polyoxymethylene from DuPont (Delrin), Ultem® (polyetherimide) from G.E. Plastics, PrimoSpire®, etc..

In accordance with the invention, the polymerizable composition can be introduced (dispensed) into a cavity formed by a mold according to any known methods.

After the polymerizable composition is dispensed into the mold, it is polymerized to produce a photochromic SiHy contact lens. Crosslinking may be initiated thermally or actinically, preferably by exposing the polymerizable composition in the mold to a spatial limitation of actinic radiation to crosslink the polymerizable components in the polymerizable composition.

Opening of the mold so that the molded photochromic SiHy contact lens can be removed from the mold may take place in a manner known perse.

The molded photochromic SiHy contact lenses can be subject to lens extraction with a liquid extraction medium to remove unpolymerized polymerizable components and formed and oligomers. In accordance with the invention, the extraction liquid medium is any solvent capable of dissolving the organic solvent, unpolymerized polymerizable materials, and oligomers in the dry contact lens. Water, any organic solvents known to a person skilled in the art, or a mixture thereof can be used in the invention. Preferably, the organic solvents used extraction liquid medium are water, a buffered saline, a C1-C3 alkyl alcohol, 1 ,2-propylene glycol, a polyethyleneglycol having a number average molecular weight of about 400 Daltons or less, a C1-C6 alkylalcohol, or combinations thereof.

After extraction, photochromic silicone hydrogel contact lens can be hydrated in water or an aqueous solution to replace the liquid extraction medium, according to any method known to a person skilled in the art.

The hydrated photochromic silicone hydrogel contact lens can further subject to further processes, such as, for example, surface treatment, packaging in lens packages with a packaging solution which is well known to a person skilled in the art; sterilization such as autoclave at from 118 to 124°C for at least about 30 minutes; and the like.

Lens packages (or containers) are well known to a person skilled in the art for autoclaving and storing a soft contact lens. Any lens packages can be used in the invention. Preferably, a lens package is a blister package which comprises a base and a cover, wherein the cover is detachably sealed to the base, wherein the base includes a cavity for receiving a sterile packaging solution and the contact lens.

Lenses are packaged in individual packages, sealed, and sterilized (e.g., by autoclave at about 120°C or higher for at least 30 minutes under pressure) prior to dispensing to users. A person skilled in the art will understand well how to seal and sterilize lens packages.

A photochromic SiHy contact lens of the invention can also be obtained from a polymerizable composition which is prepared by adding a desired amount of at least one photochromic polydiorganosiloxane vinylic crosslinker into any SiHy lens formulation for producing commercially-available SiHy contact lenses.

A SiHy contact lens formulation can also comprise other necessary components known to a person skilled in the art, such as, for example, free-radical initiators (e.g., thermal polymerization initiators, photoinitiators), a UV-absorbing vinylic monomer, a high-energy-violet-light (“HEVL”) absorbing vinylic monomer, a visibility tinting agent (e.g., reactive dyes, polymerizable dyes, pigments, antimicrobial agents (e.g., preferably silver nanoparticles), a bioactive agent, leachable polymeric wetting agents (e.g., non- polymerizable hydrophilic polymers, etc.), leachable tear-stabilizing agents (e.g., phospholipids, monoglycerides, diglycerides, triglycerides, glycolipids, glyceroglycolipids, sphingolipids, sphingo-glycolipids, etc.), and mixtures thereof, as known to a person skilled in the art.

Any thermal polymerization initiators can be used in the invention. Suitable thermal polymerization initiators are known to the skilled artisan and comprise, for example peroxides, hydroperoxides, azo-bis(alkyl- or cycloalkylnitriles), persulfates, percarbonates, or mixtures thereof. Examples of preferred thermal polymerization initiators include without limitation benzoyl peroxide, t-butyl peroxide, t-amyl peroxybenzoate, 2,2-bis(tert-butylperoxy)butane, 1 ,1 -bis(tert-butylperoxy)cyclohexane, 2,5-Bis(tert-butylperoxy)-2,5- dimethylhexane, 2,5-bis(tert-butylperoxy)-2,5- dimethyl-3- hexyne, bis(1-(tert-butylperoxy)-1-methylethyl)benzene, 1 ,1-bis(tert-butylperoxy)-3,3,5- trimethylcyclohexane, di-t-butyl-diperoxyphthalate, t-butyl hydroperoxide, t-butyl peracetate, t-butyl peroxybenzoate, t-butylperoxy isopropyl carbonate, acetyl peroxide, lauroyl peroxide, decanoyl peroxide, dicetyl peroxydicarbonate, di(4-t- butylcyclohexyl)peroxy dicarbonate (Perkadox 16S), di(2-ethylhexyl)peroxy dicarbonate, t-butylperoxy pivalate (Lupersol 11); t-butylperoxy-2-ethylhexanoate (Trigonox 21-C50), 2,4- pentanedione peroxide, dicumyl peroxide, peracetic acid, potassium persulfate, sodium persulfate, ammonium persulfate, 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) (VAZO 33), 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride (VAZO 44), 2,2'- azobis(2-amidinopropane) dihydrochloride (VAZO 50), 2,2'-azobis(2,4- dimethylvaleronitrile) (VAZO 52), 2,2'-azobis(isobutyronitrile) (VAZO 64 or AIBN), 2,2'- azobis-2-methylbutyronitrile (VAZO 67), 1 ,1-azobis(1-cyclohexanecarbonitrile) (VAZO 88); 2,2'-azobis(2-cyclopropylpropionitrile), 2,2'-azobis(methylisobutyrate), 4,4'-Azobis(4- cyanovaleric acid), and combinations thereof. Preferably, the thermal initiator is 2,2’- azobis(isobutyronitrile) (AIBN or VAZO 64).

Suitable photoinitiators are benzoin methyl ether, diethoxyacetophenone, a benzoylphosphine oxide, 1 -hydroxycyclohexyl phenyl ketone and Darocur and Irgacur types, preferably Darocur 1173® and Darocur 2959®, Germanium-based Norrish Type I photoinitiators (e.g., those described in US 7,605,190). Examples of benzoylphosphine initiators include 2,4,6-trimethylbenzoyldiphenylophosphine oxide; bis-(2,6- dichlorobenzoyl)-4-N-propylphenylphosphine oxide; and bis-(2,6-dichlorobenzoyl)-4-N- butylphenylphosphine oxide. Reactive photoinitiators which can be incorporated, for example, into a macromer or can be used as a special monomer are also suitable. Examples of reactive photoinitiators are those disclosed in EP 632329. Preferably, a SiHy lens formulation for making a photochromic SiHy contact lenses comprises at least one photoinitiator which can be initiated by visible lights, such as, benzoylphosphine oxide photoinitiators, Germanium-based Norrish Type I photoinitiators, or combinations thereof.

A polymerizable composition (SiHy lens formulation) can be a solventless clear liquid prepared by mixing all polymerizable components and other necessary component or a solution prepared by dissolving all of the desirable components in any suitable solvent, such as, a mixture of water and one or more organic solvents miscible with water, an organic solvent, or a mixture of one or more organic solvents, as known to a person skilled in the art. The term “solvent” refers to a chemical that cannot participate in free- radical polymerization reaction.

A solventless lens SiHy lens formulation typically comprises at least one blending vinylic monomer as a reactive solvent for dissolving all other polymerizable components of the solventless SiHy lens formulation. Examples of preferred blending vinylic monomers are described later in this application. Preferably, methyl methacrylate is used as a blending vinylic monomer in preparing a solventless SiHy lens formulation.

Any solvents can be used in the invention. Example of preferred organic solvents includes without limitation, tetrahydrofuran, tripropylene glycol methyl ether, dipropylene glycol methyl ether, ethylene glycol n-butyl ether, ketones (e.g., acetone, methyl ethyl ketone, etc.), diethylene glycol n-butyl ether, diethylene glycol methyl ether, ethylene glycol phenyl ether, propylene glycol methyl ether, propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, tripropylene glycol n-butyl ether, propylene glycol n-butyl ether, dipropylene glycol n-butyl ether, tripropylene glycol n-butyl ether, propylene glycol phenyl ether dipropylene glycol dimetyl ether, polyethylene glycols, polypropylene glycols, ethyl acetate, butyl acetate, amyl acetate, methyl lactate, ethyl lactate, i-propyl lactate, methylene chloride, 2-butanol, 1 -propanol, 2-propanol, menthol, cyclohexanol, cyclopentanol and exonorborneol, 2-pentanol, 3-pentanol, 2-hexanol, 3-hexanol, 3- methyl-2-butanol, 2-heptanol, 2-octanol, 2-nonanol, 2-decanol, 3-octanol, norborneol, tert- butanol, tert-amyl alcohol, 2-methyl-2-pentanol, 2,3-dimethyl-2-butanol, 3-methyl-3- pentanol, 1-methylcyclohexanol, 2-methyl-2-hexanol, 3,7-dimethyl-3-octanol, 1-chloro-2- methyl-2-propanol, 2-methyl-2-heptanol, 2-methyl-2-octanol, 2-2-methyl-2-nonanol, 2- methyl-2-decanol, 3-methyl-3-hexanol, 3-methyl-3-heptanol, 4-methyl-4-heptanol, 3- methyl-3-octanol, 4-methyl-4-octanol, 3-methyl-3-nonanol, 4-methyl-4-nonanol, 3-methyl-

3-octanol, 3-ethyl-3-hexanol, 3-methyl-3-heptanol, 4-ethyl-4-heptanol, 4-propyl-4-heptanol,

4-isopropyl-4-heptanol, 2,4-dimethyl-2-pentanol, 1-methylcyclopentanol, 1- ethylcyclopentanol, 1-ethylcyclopentanol, 3-hydroxy-3-methyl-1 -butene, 4-hydroxy-4- methyl-1 -cyclopentanol, 2-phenyl-2-propanol, 2-methoxy-2-methyl-2-propanol 2,3,4- trimethyl-3-pentanol, 3,7-dimethyl-3-octanol, 2-phenyl-2-butanol, 2-methyl-1-phenyl-2- propanol and 3-ethyl-3-pentanol, 1-ethoxy-2-propanol, 1-methyl-2-pyrrolidone, N,N- dimethylpropionamide, dimethyl formamide, dimethyl acetamide, dimethyl propionamide, N-methyl pyrrolidinone, and mixtures thereof.

Numerous SiHy lens formulations have been described in numerous patents and patent applications published by the filing date of this application and have been used in producing commercial SiHy contact lenses. Examples of commercial SiHy contact lenses include, without limitation, asmofilcon A, balafilcon A, comfilcon A, delefilcon A, efrofilcon

A, enfilcon A, fanfilcon A, galyfilcon A, lotrafilcon A, lotrafilcon B, narafilcon A, narafilcon

B, senofilcon A, senofilcon B, senofilcon C, smafilcon A, somofilcon A, and stenfilcon A.

A SiHy lens formulation (i.e., polymerizable composition) can be cured (polymerized) thermally or actinically as known to a person skilled in the art, preferably in molds for cast molding of contact lenses.

The thermal polymerization is carried out conveniently, for example at a temperature of from 25 to 120°C and preferably 40 to 100°C. The reaction time may vary within wide limits, but is conveniently, for example, from 1 to 24 hours or preferably from 2 to 12 hours. It is advantageous to previously degas the components and solvents used in the polymerization reaction and to carry out said copolymerization reaction under an inert atmosphere, for example under a nitrogen or argon atmosphere.

The actinic polymerization can then be triggered off by actinic radiation, for example light, in particular UV light or visible light of a suitable wavelength. The spectral requirements can be controlled accordingly, if appropriate, by addition of suitable photosensitizers.

Although various embodiments of the invention have been described using specific terms, devices, and methods, such description is for illustrative purposes only. The words used are words of description rather than of limitation. It is to be understood that changes and variations may be made by those skilled in the art without departing from the spirit or scope of the present invention, which is set forth in the following claims. In addition, it should be understood that aspects of the various embodiments may be interchanged either in whole or in part or can be combined in any manner and/or used together, as illustrated below:

1. A photochromic polydiorganosiloxane vinylic crosslinker, comprising:

(1) a polydiorganosiloxane segment comprising dimethylsiloxane units and at least one photochromic siloxane unit having one methyl substituent and one photochromic organic substituent having at least one photochromic moiety; and (2) two terminal ethylenically-unsaturated groups. The photochromic polydiorganosiloxane vinylic crosslinker of embodiment 1 , wherein the polydiorganosiloxane segment comprises from 3 to 500 dimethylsiloxane units. The photochromic polydiorganosiloxane vinylic crosslinker of embodiment 1 , wherein the polydiorganosiloxane segment comprises from 5 to 450 dimethylsiloxane units. The photochromic polydiorganosiloxane vinylic crosslinker of embodiment 1 , wherein the polydiorganosiloxane segment comprises from 10 to 400 dimethylsiloxane units. The photochromic polydiorganosiloxane vinylic crosslinker of embodiment 1 , wherein the polydiorganosiloxane segment comprises from 20 to 350 dimethylsiloxane units. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 5, wherein the polydiorganosiloxane segment comprises from 1 to 80 photochromic siloxane units. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 5, wherein the polydiorganosiloxane segment comprises from 2 to 70 photochromic siloxane units. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 5, wherein the polydiorganosiloxane segment comprises from 3 to 60 photochromic siloxane units. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 5, wherein the polydiorganosiloxane segment comprises from 3 to 50 photochromic siloxane units. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 9, wherein the two terminal ethylenically unsaturated groups are (meth)acryloyl groups. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 10, wherein the molar ratio of the photochromic siloxane units to the dimethylsiloxane units is from about 0.002 to about 0.50. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 10, wherein the molar ratio of the photochromic siloxane units to the dimethylsiloxane units is from about 0.002 to about 0.20.13. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 10, wherein the molar ratio of the photochromic siloxane units to the dimethylsiloxane units is from about 0.004 to about 0.1. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 10, wherein the molar ratio of the photochromic siloxane units to the dimethylsiloxane units is from about x0.004 to about 0.05. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 13, wherein the photochromic polydiorganosiloxane vinylic crosslinker has a number average molecular weight of at least 1000 Daltons. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 13, wherein the photochromic polydiorganosiloxane vinylic crosslinker has a number average molecular weight of from 1500 Daltons to 80000 Daltons. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 13, wherein the photochromic polydiorganosiloxane vinylic crosslinker has a number average molecular weight of from 2000 to 50000 Daltons. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 13, wherein the photochromic polydiorganosiloxane vinylic crosslinker has a number average molecular weight of from 2500 to 25000 Dalton. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 17, wherein the photochromic polydiorganosiloxane vinylic crosslinker is defined by formula (1 ) in which: u1 is an integer of from 3 to 500 and is an integer of from 1 to 80,

E _i is a monovalent radical of

Ro is hydrogen or methyl; a1 is zero or 1 ;

X0 is O or NRNI ; R _N1 is hydrogen or a C ₁ -C ₁₅ alkyl;

L0 is a C2-C8 alkylene divalent radical or a divalent radical of L0 ’ is a C2-C8 alkylene divalent radical which has zero or one hydroxyl group; L0 ” is C3-C8 alkylene divalent radical which has zero or one hydroxyl group; X1 is -0-, -NR _NI - -NHCOO-, -OCONH-, -CONR _NI - or -NR _NI CO-;

X1’ is O or NRNI ; q1 is an integer of 1 to 20; q2 is an integer of 0 to 20;

RPC is a monovalent radica

L _e is a divalent radical of a2 is zero or 1 ; a3 is zero or an integer of from 1 to 3;

Ri is a linear or branched C1-C10 alkylene divalent radical;

R2 is a linear or branched C3-C10 alkylene divalent radical;

R3 is a direct bond or a linear or branched C1-C4 alkylene divalent radical; XPC and each X ₂ independently of others are a covalent linkage of -0-, -S-,

R _N 2 is hydrogen, a linear or branched C1-C15 alkyl, cyclohexyl, cyclopentyl, a substituted or unsubstituted phenyl, or a substituted- or unsubstituted-phenyl-Cr C ₆ alkyl; each L _x independently is a linear or branched C1-C24 alkylene divalent radical which optionally has one or more hydroxyl or CrC4-alkoxy groups or C1-C4- acylamino groups, or a divalent radical which optionally has one or more hydroxyl or CrC4-alkoxy groups and is obtained by removal of two hydrogen atoms from two different atoms of a hydrocarbon that has up to 20 carbon atoms and comprises at least one divalent radical selected from the group consisting of cycloalkylene radical, substituted cycloalkylene radical, phenylene radical, susbtituted phenylene radical, cycloheteroalkylene radical, and substituted cycloheteroalkylene radical; each R , R ₅ and R ₆ independent of one another are a linear or branched C1-C15 alkylene divalent radical which has zero or one hydroxyl group; and PC is a photochromic group.

The photochromic polydiorganosiloxane vinylic crosslinker of embodiment 18, wherein in formula (1) u1 is an integer of from 5 to 450.

The photochromic polydiorganosiloxane vinylic crosslinker of embodiment 18, wherein in formula (1 ) u1 is an integer of from 10 to 400.

The photochromic polydiorganosiloxane vinylic crosslinker of embodiment 18, wherein in formula (1) u1 is an integer of from 20 to 350.

The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 18 to 21 , wherein in formula (1) col is an integer of from 2 to 70.

The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 18 to 21 , wherein in formula (1) col is an integer of from 3 to 60.

The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 18 to 21 , wherein in formula (1) col is an integer of from 3 to 50.

The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 18 to 24, wherein PC is a monovalent organic radical that has one colorless or light-colored form and one colored form and can undergo reversible change from the colorless or light-colored form to the colored form upon exposure to UV-irradiation or HEV light and that is derived directly from at least one reactive photochromic compound that has a reactive functional group, designated as “Epc”, selected from the group consisting of wherein the E _PC has participated in a coupling reaction with a co-reactive functional group to form a covalent linkage of Xpc.

The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 18 to 25, wherein said at least one reactive photochromic compound is a naphthopyran, an indeno-fused naphthopyran (i.e., indeno-naphthopyran), a heterocyclic ring-fused naphthopyrian, a benzopyran, a phenanthropyran, a quinopyran, a quinolinopyran, a fluoroanthenopyran, an anthracene-fused pyran, a tetracene-fused pyran, a spiro(benzindoline) naphthopyran, a spiro(indoline)naphthopyran, a spiro(indoline)benzopyran, a spiro(indoline)quinopyran, a spiro(indoline)pyran, a naphthoxazine, a spirobenzopyran, a spirobenzothiopyran, a naphthacenedione, a benzoxazine, a spirooxazine, a naphthoxazine, a spiro(benzindoline)naphthoxazine, a spiro(indoline)naphthoxazine, a spiro(indoline)pyrido-benzoxazine, a spiro(indoline)benzoxazine, a spiro(benzindoline) benzoxazine, a spiro(benzindoline)pyridobenzoxazine, a spiro(indoline) fluoranthenoxazine, a spiro(indoline)-quinoxazine, a spiropiperidine-naphthopyran, a piro(indoline)pyronobenzoxazinone, a benzospiropyran, a naphthospiropyran, a spirobenzoxazine-pyrrolopyridine, a spironaphthoxazine-pyrrolopyrridine, a spiro- oxazepin-benzoxazine, a spiro-oxazepin-naphthoxazine, a spiro(indoline) benzothiazoloxazine, a spiro(indoline)benzopyrroloxazine, a spiro(indoline)quinazolino-oxazine, a spiro(indoline)-anthracenobenzoxazine, a benzofurobenzopyran, a benzothienobenzopyran, a naphthofurobenzopyran, a benzopyrano-fused naphthopyran, a spiro(isoindoline)-naphthoxazine, a spiro(isoindoline)benzoxazine, or a mixture thereof. The photochromic polydiorganosiloxane vinylic crosslinker of embodiment 26, wherein said at least one reactive photochromic compound comprises 3,3-bis(4- methoxyphenyl)-6,11 -dimethyl-13-hydroxyethoxy-13-phenyl-3H,13H-indeno [2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-bis(4-methoxyphenyl)-6,11-dimethyl-13-(2- hydroxycarbonylethyl)carboxyethoxy-13-phenyl-3H,13H-indeno [2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-bis(4-methoxyphenyl)-6,11 -dimethyl- 13-hydroxy- 13-phenyl-3H,13H-indeno [2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-bis(4-methoxyphenyl)-

6.11-dimethyl-13-(2-hydroxycarbonylethyl)carboxy-13-pheny l-3H,13H-indeno [2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-bis(4-methoxyphenyl)-6,11-dimethyl-13-hydroxy- 13-propyl-3H,13H-indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-bis(4-methoxyphenyl)-

6.11-dimethyl-13-(2-hydroxycarbonylethyl)carboxy-13-propy l-3H,13H- indeno[2’,3’:3,4]naphtho[1 ,2-b]pyran; 3,3-di(4-methoxyphenyl)-10,11 -dimethoxy-13- hydroxy-13-ethyl-3H,13H-indeno[2,1-f]naphtho[1 ,2-b]pyran; 3,3-di(4- methoxyphenyl)-10,11-dimethoxy-13-(2-hydroxycarbonylethyl)ca rboxy-13-ethyl- 3H,13H-indeno[2,1-f]naphtho[1 ,2-b]pyran; 3,3-bis(4-methoxyphenyl)-7-methoxy-11- phenyl-13-hydroxymethyl-13-methyl-3H,13H-indeno[2’,3’:3, 4] naphtho[1 ,2-b]pyran; 3,3-bis(4-methoxyphenyl)-7-methoxy-11 -phenyl-13-(2- hydroxycarbonylethyl)carboxymethyl-13-methyl-3H,13H- indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-bis(4-methoxyphenyl)-7-methoxy-11 - phenyl-13-hydroxy-13-methyl-3H,13H-indeno[2’,3’:3,4]naph tho[1 ,2-b]pyran; 3,3- bis(4-methoxyphenyl)-7-methoxy-11 -phenyl-13-(2-hydroxycarbonylethyl)carboxy- 13-methyl-3H,13H-indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-bis(4-methoxyphenyl)- 11-phenyl-13-hydroxy-13-methyl-3H,13H-indeno[2’,3’:3,4]n aphtho[1 ,2-b]pyran; 3,3- bis(4-methoxyphenyl)-11 -phenyl-13-(2-hydroxycarbonylethyl)carboxy-13-methyl- 3H,13H-indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-di(4-methoxyphenyl)-6,7,10,11- tetramethoxy-13-hydroxy-13-ethyl-3H,13H-indeno[2,1-f]naphtho [1 ,2-b]pyran; 3,3- bis(4-methoxyphenyl)-6,7,10,11-tetramethyl-13-(2-hydroxycarb onylethyl)carboxy- 13-methyl-3H,13H-indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-di(4-methoxyphenyl)- 6,7-dimethoxy-13-hydroxy-13-ethyl-3H,13H-indeno[2,1-f]naphth o[1 ,2-b]pyran; 3,3- bis(4-methoxyphenyl)-11 -(4-(4,5-diphenyl-1 H-imidazol-2-yl)phenyl-13,13-dimethyl- 3H,13H-indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-di(4-methoxyphenyl)-6-methoxy- 7-(3-hydroxymethylenepiperidin-1 -yl)-13,13-dimethyl-3H,13H- indeno[2’,3':3,4]naphtho[1.2-b]pyran; 3,3-di(4-methoxyphenyl)-6-methoxy-7-(3-(2- hydroxycarbonylethyl)-carboxymethylenepiperidin-1-yl)-13,13- dimethyl-3H,13H- indeno[2’,3':3,4]naphtho[1.2-b]pyran; 3,3-di(4-methoxyphenyl)-6,7-dimethoxy-13- hydroxy-13-butyl-3H,13H-indeno[2,1-f]naphtho[1 ,2-b]pyran; 3,3-di(4- methoxyphenyl)-6,11 ,13-trimethyl-13-(2-(2-hydroxyethoxy)-ethoxy)-indeno[2,1- f]naptho[1 ,2-b]pyran; 3,3-di(4-methoxyphenyl)-6,11 ,13-trimethyl-13-(2-(2-(2-(2- hydroxyethoxy)ethoxy)ethoxy)ethoxy)-indeno[2,1-f]naptho[1 ,2-b]pyran; 3,3-diphenyl- 13-hydroxy-13-(2-oxo-2-ethoxyethyl)-1 H-indeno[2,1 -f]naphtho[1 ,2-b]pyran; 3,3-di(4- methoxyphenyl)-6,11 -dimethyl-13-hydroxy-13-(2-oxo-2-ethoxyethyl)-1 H-indeno[2,1- f]naphtho[1 ,2-b]pyran; 3,3-di(4-methoxyphenyl)-6,11 -dimethyl-13-butyl- 13-hydroxy- indeno[2,1 -f]naphtho[1 ,2-b]pyran; 3,3-bis(4-hydroxyphenyl)-7-methoxy-11 -phenyl- 13,13-diethyl-3H,13H-indeno[2’,3’:3,4]naphtho[1 ,2-b]pyran; 3,3-bis(4- hydroxyphenyl)-7-methoxy-11 -phenyl-13,13-dipropyl-3H,13H- indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-bis(4-hydroxyphenyl)-7-methoxy-11 - phenyl-13-carbomethoxy-13-methyl-3H,13H-indeno[2’,3’:3,4 ] naphtho[1 ,2-b]pyran; 3,3-diphenyl-6,7-dimethoxy-13-methyl-13-methyl-13-hydroxyeth oxy-ethoxyethoxy- 3H,13H-indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-diphenyl-6,7,10,11-tetramethoxy- 13-ethyl-13-methyl-13-hydroxyethoxyethoxy-3H,13H-indeno[2’ ,3’:3,4]naphtho [1 ,2- b]pyran; 6,7-dimthoxy-2,2-diphenyl-13-hydroxy-13-butyl-2H,13H-indeno[ 1’,2’:4,3] naphtho[1 ,2-b]pyran; 6,7-dimthoxy-2,2-diphenyl-13-hydroxy-13-methyl-2H,13H- indeno[1’,2’:4,3]naphtho[1,2-b]pyran; 6, 7-dimthoxy-2,2-diphenyl-13-hydroxy- 2H,13H-indeno[1 ’,2’:4,3]naphtho[1,2-b]pyran; 3-(4-allyloxyphenyl)-3-(4- morpholinophenyl)-7-methoxy-11-phenyl-13,13-dimethy-3H,13H- indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3-(4-fluorophenyl)-3-(4-butoxyphenyl)-10- (piperazin-1-yl)-6-trifluoromethyl-13,13-dimethyl-3H,13H- indeno[2’,3’:3:4]naphtho[1,2-b]pyran; 3-(4-fluorophenyl)-3-(4-butoxyphenyl)-10-(4- hydroxybenzamido)-6-trifluoromethyl-13,13-dimethyl-3H,13H- indeno[2’,3’:3:4]naphtho[1,2-b]pyran; 3-(4-fluorophenyl)-3-(4-butoxyphenyl)-10-vinyl- 6-trifluoromethyl-13,13-dimethyl-3H,13H-indeno[2’,3’:3:4 ]naphtho[1 ,2-b]pyran; 3-(4- fluorophenyl)-3-(4-butoxyphenyl)-10-(carboxylic acid)-6-trifluoromethyl-13,13- dimethyl-3H,13H-indeno[2’,3’:3:4]naphtho[1 ,2-b]pyran; 3-(4-fluorophenyl)-3-(4- methoxyphenyl)-6-methoxy-7-(4-hydroxypiperidin-1-yl)-13,13-d imethyl-3H,13H- indeno[2',3’:3,4]naphtho[1 ,2-b]pyran; 3-(4-fluorophenyl)-3-(4-methoxyphenyl)-6- methoxy-7-(4-(2-hydroxycarbonylethyl) carboxypiperidin-1-yl)-13,13-dimethyl- 3H,13H-indeno[2',3’:3,4]naphtho[1,2-b]pyran; 3-(4-fluorophenyl)-3-(4- morpholinophenyl)-6-methoxy-7-(4-hydroxypiperidin-1 -yl)-13,13-dimethyl-3H,13H- indeno[2',3’:3,4]naphtho[1.2-b]pyran; 3-(4-fluorophenyl)-3-(4-morpholinophenyl)-6- methoxy-7-(4-(2-hydroxycarbonylethyl) carboxypiperidin-1-yl)-13,13-dimethyl- 3H,13H-indeno[2',3’:3,4] naphtho[1 .2-b]pyran; 3-(4-hydroxyethoxyphenyl)-3-(4- methoxyphenyl)-11 -(4-(N,N-dimethylamino)phenyl)-13,13-dimethyl-3H,13H- indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3-(4-methoxyphenyl)-3-(2,4-dimethoxyphenyl)- phenyl-6,11 -dimethoxy-13-methyl-13-methyl-13-hydroxyethoxyethoxyethoxy- 3H,13H-indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3-(4-methoxyphenyl)-3-(3-methyl-4- methoxyphenyl)-13-hydroxy-indeno[2,1 -f]naphtho[1 ,2-b]pyran; 3-(4-methoxyphenyl)- 3-(4-morpholinophenyl)-6,7, 10,11 -tetramethoxy-13-hydroxy- 13-ethyl-3H, 13H- indeno[2,1 -f]naphtho[1 ,2-b]pyran; 3-(4-methoxyphenyl)-3-(4-morpholinophenyl)- 6,7,10,11 -tetramethoxy-13-hydroxy-13-butyl-3H,13H-indeno[2,1-f]naphth o[1 ,2- b]pyran; 3-(4-methoxyphenyl)-3-(4-morpholinophenyl)-6,7-dimethoxy-13- hydroxy- 13-ethyl-3H,13H-indeno [2,1-f]naphtho[1 ,2-b]pyran; 3-(4-methoxyphenyl)-3-(4- morpholinophenyl)-6,7-dimethoxy-13-hydroxy-13-methyl-3H,13H- indeno[2,1- f]naphtho[1 ,2-b]pyran; 3-(4-methoxyphenyl)-3-(4-morpholinophenyl)-13-oxo- 3H,13H-indeno[2,1-f]naphtho[1 ,2-b]pyran; 3-(4-methoxyphenyl)-3-phenyl-6- methoxy-7-mprphlino-13-methyl-13-methyl-13-hydroxyethoxyetho xyethoxy-3H,13H- indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3-(4-methoxyphenyl)-3-phenyl-6,11 - dimethoxy-13-methyl-13-methyl-13-hydroxyethoxyethoxy-3H,13H- indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 2-(4-methoxyphenyl)-2-(4-morpholinophenyl)- 5-hydroxy-6-carboethoxy-2H-naphtho[1 ,2-b] pyran; 3-(4-morpholinophenyl)-3- phenyl-6,7-dimethoxy-13-hydroxy-13-ethyl-3H,13H-indeno[2,1-f ]naphtho[1 ,2- b]pyran; 3-(4-morpholinophenyl)-3-phenyl-6,7-dimethoxy-13-hydroxy-13- butyl- 3H,13H-indeno[2,1-f]naphtho[1 ,2-b]pyran; 3-(4-morpholinophenyl)-3-phenyl-6,7- dimethoxy-13-oxo-3H,13H-indeno[2,1-f]naphtho[1 ,2-b]pyran; 3-phenyl-3-(4- hydroxyethoxyphenyl)-6-methoxy-7-morpholino-13,13-dimethyl-3 H,13H- indeno[2',3’:3,4] naphtho[1 ,2-b]pyran; 3-phenyl-3-(4-(2- hydroxycarbonylethyl)carboxyethoxyphenyl)-6-methoxy-7-morpho lino-13,13- dimethyl-3H,13H-indeno[2',3’:3,4]naphtho[1,2-b]pyran; 3-phenyl-3-(4-(2- hydroxyethoxy)phenyl)-6-methoxy-7-piperidino-13,13-dimethy-3 H,13H- indene[2’,3’:3,4]naphtho[1,2-b]pyran; 3-phenyl-3-(4-(2-(2-hydroxycarbonylethyl)- carboxyethoxy)phenyl)-6-methoxy-7-piperidino-13,13-dimethy-3 H,13H- indene[2’,3’:3,4] naphtho[1,2-b]pyran; 3-phenyl-3-(4-hydroxyphenyl)-6,7-dimethoxy- 13,13-dimethyl-3H,13H-indeno[2’,3’:3,4]naphtho[l,2-b]pyr an; 3-phenyl-3-(4- hydroxyethoxy)phenyl)-6,7-dimethoxy-13,13-dimethyl-3H,13H- indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3-phenyl-3-(4-(2- hydroxycarbonylethyl)carboxyethoxy)phenyl)-6,7-dimethoxy-13, 13-dimethyl- 3H,13H-indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3-phenyl-3-(4-(2- hydroxycarbonylethyl)carboxy-phenyl)-6,7-dimethoxy-13,13-dim ethyl-3H,13H- indeno[2’,3’:3,4]naphtho[l,2-b]pyran; 3-phenyl-3-(4-(4-(2-hydroxyethyl)piperazin-1 - yl)phenyl)-13,13-dimethyl-3H,13H-indeno[2’,3’:3,4]naphth o[1 ,2-b]pyran; 3-phenyl-3- (4-(4-(2-(2-hydroxycarbonylethyl)-carboxyethyl)piperazin-1 -yl)phenyl)-13,13- dimethyl-3H,13H-indeno[2’,3’:3,4]naphtho-[1 ,2-b]pyran; 3-phenyl-3-(4- methoxyphenyl)-6-methoxy-7-piperazinyl-13,13-dimethyl-3H,13H - indene[2’,3’:3,4]naphtho[1,2-b]pyran; 3-phenyl-3-(4-methoxyphenyl)-6-methoxy-7- (3-hydroxymethylenepiperidin-1 -yl)-13,13-dimethyl-3H,13H-indeno [2’,3”:3.4]naphtho[1.2-b]pyran; 3-phenyl-3-(4-methoxyphenyl)-6-methoxy-7-(3-(2- hydroxycarbonylethyl) carboxymethylenepiperidin-1 -yl)-13,13-dimethyl-3H,13H- indeno[2’,3”:3.4]naphtho[1 2-b]pyran; 3-phenyl-3-(4-methoxyphenyl)-6-methoxy-7- (4-hydroxypipendin-1 -yl)-13,13-dimethyl-3H,13H-indeno[2',3 ^, :3,4]naphtho[1 ,2- b]pyran; 3-phenyl-3-(4-methoxyphenyl)-6-methoxy-7-(4-(2- hydroxycarbonylethyl)carboxypipendin-1 -yl)-13,13-dimethyl-3H,13H- indeno[2',3':3,4]naphtho[1 ,2-b]pyran; 3-phenyl-3-(4-(4-methoxyphenyl-piperazin-1 - yl)phenyl)-13,13-dimethyl-6-methoxy-7-hydroxy-indeno [2’,3’:3,4]naphtho[1,2- b]pyran; 3-phenyl-3-(4-(4-methoxyphenylpiperazin-1-yl)phenyl)-13,13-d imethyl-6- methoxy-7-(2-hydroxy-2-methyl-3-butyn-4-yl)-indeno[2’,3’ :3,4]naphtho [1 ,2-b]pyran; 3-phenyl-3-(4-morpholinophenyl)-6-methoxy-7-(3-hydroxymethyl ene-piperidin-1 -yl)- 13.13-dimethyl-3H,13H-indeno[2',3’:3,4]naphtho[1 ,2-b]pyran; 3-phenyl-3-(4- morpholinophenyl)-6-methoxy-7-(3-(2-hydroxycarbonylethyl) carboxymethylene- piperidin-1 -yl)-13,13-dimethyl-3H,13H-indeno [2’,3’:3.4]naphtho[1 ,2-b]pyran; 3- phenyl-3-(4-morpholinophenyl)-6-methoxy-7-(3-(2- hydroxycarbonylethyl)carboxymethylene-piperidin-1-yl)-13,13- dimethyl-3H,13H- indeno [2',3’:3,4]naphtho[1 ,2-b]pyran; 3-phenyl-3-(4-morpholinophenyl)-6-methoxy- 7-(4-hydroxypiperidin-1-yl)-13,13-dimethyl-3H,13H-indeno[2� �,3’:3,4]naphtho[1.2- b]pyran; 3-phenyl-3-(4-morpholinophenyl)-6-methoxy-7-(4-(2- hydroxycarbonylethyl)carboxypiperidin-1 -yl)-13,13-dimethyl-3H,13H-indeno[2’,3’:3,4] naphtho[1.2-b]pyran; 3-phenyl-3-(4-morpholinophenyl)-6-methoxy-7-piperazinyl-

13.13-dimethyl-3H,13H-indeno[2’,3’:3,4]naphtho [1 .2-b]pyran; 3-phenyl-3-(4- morpholinophenyl)-6,11 -dimethyl-13-hydroxy-13-(1 -oxo-methoxyprop-2-yl)-1 H- indeno[2,1 -f]naphtho[1 ,2-b]pyran; 3-phenyl-3-(4-(4-phenylpiperazino)-phenyl)-6- methoxy-7-(4-hydroxypiperidin-1 -yl)-13,13-dimethyl-3H,13H-indeno[2’,3':3,4] naphtho[1.2-b]pyran; 3-phenyl-3-(4-(4-phenylpiperazino)phenyl)-6-methoxy-7-(4-(2- hydroxycarbonylethyl) carboxypiperidin-1-yl)-13,13-dimethyl-3H,13H-indeno[2’,3': 3,4] naphtho[1.2-b]pyran; 3-phenyl-3-(4-piperazinylphenyl)-6,11-dimethoxy-13,13- dimethyl-3H,13H-indeno[2’,3’:3,4]naphtho[1 ,2-b]pyran; 3-phenyl-3-(4- piperazinylphenyl)-6-methoxy-7-piperidinyl-13,13-dimethyl-3H ,13H- indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3-phenyl-3-(4-(3-methylpiperazin-1-yl)phenyl)- 6-methoxy-7-(decahydroisoquinolin-2-yl)-11 -ferf-butyl-13,13-dimethyl-3H,13H- indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3-(4-methoxyphenyl)-3-(4-morpholinophenyl)- 16-(ethoxycarnobyl)methyl-16-hydroxy-3,16-dihydrobenzofuro[2 ’,3’:7,8] indeno[2’,3’:3,4]naphtho[1,2-b]pyran; 3-phenyl-3-(4-methoxyphenyl)-16- (ethoxycarnobyl)-methyl-16-hydroxy-3,16-dihydrobenzofuro [2”,3”:6’,7’]indeno[3’,2’:4,3]naphtho[1 ,2-b]pyran; 3-phenyl-3-(4-morpholinophenyl)- 16-(ethoxycarnobyl)methyl-16-hydroxy-3,16- dihydrobenzofuro[2”,3”:6’,7’]indeno[3’,2’:4,3] naphtho[1,2-b]pyran; 3,3-di(4- methoxyphenyl)-16-(ethoxycarbonyl)methyl-16-hydroxy-3,16-dih ydro- benzofuro[2’,3’:7,8]indeno[2’,3’:3,4] naphtho[1 ,2-b]pyran; 3,3-di(4-methoxyphenyl)- 16-hydroxy-16-ethyl-16H-benzofuro[2’,3’:7,8] indeno[2’,3’:3,4]naphtho [1 ,2-b]pyran; 3,3-di(4-methoxyphenyl)-16-hydroxy-16H-benzofuro [2”,3”:6,7]indeno [3’,2’:4,3]naphtho[1,2-b]pyran; 3,3-di(4-methoxyphenyl)-16-hydroxy-16-ethyl-16H- benzofuro[2”,3”:6,7]indeno[3’,2’:4,3]naphtho[1,2-b]p yran; 3-(4-methoxyphenyl)-3- (2,3-diydrobenzofur-5-yl)-13-hydroxy-13-methyl-indeno[2,1-f] naphtho[1 ,2-b]pyran; 3- (4-methoxyphenyl)-3-(2,3-dihydrobenzofur-5-yl)-6,11-difluoro -13-hydroxy-13-(1-oxo- methoxyprop-2-yl)-1 H-indeno[2,1-f]naphtho[1 ,2-b]pyran, or a mixture thereof. The photochromic polydiorganosiloxane vinylic crosslinker of embodiment 26 or 27, wherein said at least one reactive photochromic compound comprises 2,2-di(4- fluorophenyl)-5-hydroxycarbonyl-6-phenyl-9-methoxy-2H-naphth o[1 ,2-b]pyran; 2,2- bis(4-methylphenyl)-5-methoxycarbonyl-6-hydroxy-2H-naphtho[1 ,2-b]pyran ; 2,2- bis(4-methoxyphenyl)-5-methoxycarbonyl-6-hydroxy-[2H]-naphth o[1 ,2-b]pyran; 2,2- bis(4-methoxyphenyl)-5-methoxyethoxycarbonyl-6-methyl-8-viny l-2H-naphtho[1 ,2- b]pyran; 2,2-bis(4-methoxyphenyl)-5-methoxyethoxycarbonyl-6-methyl-8- hydroxycarbonyl-2H-naphtho [1 ,2-b]pyran; 2,2-bis(4-methoxyphenyl)-5- methoxycarbonyl-6-(2-hydroxyethoxy)ethoxy-[2H]-naphtho[1 ,2-b]pyran; 2,2-bis(4- methoxyphenyl)-5-methoxycarbonyl-6-phenyl-9-(2-hydroxyethoxy )-[2H]- naphtho[1 ,2-b]pyran; 2,2-bis(4-methoxyphenyl)-5-methoxy-carbonyl-6-(4-(2- hydroxyethoxy)phenyl)-[2H]-naphtho[1 ,2-b]pyran; 2,2-bis(4-methoxyphenyl)-5- diphenylmethylol-6-hydroxy-2H-naphtho[1 ,2-b]pyran; 2,2-bis(4-methoxyphenyl)-5- diphenylmethylol-6-methoxy-2H-naphtho[1 ,2-b]pyran; 2,2-bis(4-methoxyphenyl)-5- (2-hydroxyethoxylcarbonyl)-6-phenyl-[2H]-naphtho[1 ,2-b]pyran; 2,2-bis(4- methoxyphenyl)-5-(2-(2-hydroxyethoxy)ethoxycarbonyl)-6-pheny l-[2H]-naphtho[1 ,2- b]pyran; 2,2-bis(4-methoxyphenyl)-5-(2-(2-(2-hydroxyethoxy)ethoxy)- ethoxycarbonyl)-6-phenyl-[2H]-naphtho[1 ,2-b]pyran; 2,2-bis(4-methoxyphenyl)-5-(2- (2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)-ethoxycarbonyl)-6-phen yl-[2H]-naphtho[1 ,2- b]pyran; 2,2-bis(4-methoxyphenyl)-5-hydroxymethyl-6-methyl-9-methoxy- 2H- naphtho[1 ,2-b]pyran; 2,2-bis(4-methoxyphenyl)-5-hydroxymethyl-6-phenyl-2H- naphtho[1 ,2-b]pyran; 2,2-bis(4-methoxyphenyl)-5-hydroxymethyl-6-methoxy-2H- naphtho[1 ,2-b]pyran; 2,2-bis(4-methoxyphenyl)-5-methoxycarbonyl-6-(3- aminophenyl)-2H-naphtho[1 ,2-b]pyran; 2,2-bis(4-methoxyphenyl)-2,5,7-trihydro-7- methylidine-5-oxo-furo-[3’,4’:3,4]naphtho[1,2-b]pyran; 2,2-bis(4-methoxyphenyl)-5- phenylthio-6-hydroxy-2H-naphtho[1 ,2-b]pyran; 3,3-di(4-methoxyphenyl)-13-hydroxy- 13-methyl-indeno[2, 1 -f]naphtho[1 ,2-b]pyran ; 3,3-di(4-methoxyphenyl)-9- methoxycarbonyl-8-(2-hydroxyethoxy)ethoxy-[3H]-naptho[1 ,2-b]pyran; 2,2-diphenyl- 5-hydroxycarbonyl-9-methoxy-2H-naphtho[1 ,2-b]pyran; 2,2-diphenyl-5- hydroxycarbonyl-8,9-dimethoxy-2H-naphtho[1 ,2-b]pyran; 2,2-diphenyl-5-hydroxy-6- carboethoxy-2H-naphtho[1 ,2-b]pyran; 2,2-diphenyl-5-hydroxy-6- morpholinocarbonyl-2H-naphtho[1 ,2-b]pyran; 2,2-diphenyl-5-hydroxy-6- carboethoxy-2H-naphtho[1 ,2-b]pyran; 2,2-diphenyl-5-hydroxy-6-carbomethoxy-9- methoxy-2H-naphtho[1 ,2-b]pyran; 2,2-diphenyl-5-hydroxy-6-morpholinocarbonyl- 2H-naphtho[1 ,2-b]pyran; 2,2-diphenyl-5-methylol-6-(3- dimethylaminopropyl)methylamino-2H-naphtho[1 ,2-b]pyran;2,2-diphenyl-2,5,7- trihydro-7-methyliden-5-oxofuro-[3’,4’:3,4]naphtho[1,2-b ]pyran; 2,2- spiroadamantylene-5-phenylthio-6-hydroxy-2H-naphtho[1 ,2-b]pyran; 2,2-diphenyl)- 5-methoxycarbonyl-6-hydroxy-2H-naphtho[1 ,2-b]pyran; 2,2-spiro-admamtylene-5- methoxycarbonyl-6-hydroxy-2H-naphtho[1 ,2-b]pyran, 3,3-diphenyl-8-hydroxy-9- carbopropoxy-3H-naphtho[2,1-b]pyran; 2,2,5-triphenyl-6-carboethoxy-2H- naphtho[1 ,2-b]pyran; 2,2,6-triphenyl-5-(2-(2-(2-(2-hydroxyethoxy)ethoxy)- ethoxy)ethoxy)carbonyl-[2H]-naphtho[1 ,2-b]pyran; 2,2,6-triphenyl-5-(2-(2-(2-oxiran- 2-ylmethoxy)ethoxy)ethoxy)ethoxycarbonyl)-[2H]-naphtho[1 ,2-b]pyran; 2-(4- methoxyphenyl)-2-(4-morpholinophenyl)-5-hydroxy-6-carboethox y-2H-naphtho[1 ,2- b]pyran; 2-(4-methoxyphenyl)-2-tert-butyl-5-methoxy-carbonyl-6-hydrox y-2H- naphtho[1 ,2-b]pyran; 2-(4-methoxyphenyl)-2-phenyl-5-methoxycarbonyl-6-hydroxy- 2H-naphtho[1 ,2-b]pyran; 2-(4-(2-(2-hydroxyethoxy)ethoxy)-ethoxyphenyl)-2-phenyl- 5-methoxycarbonyl-6-methyl-9-methoxy-[2H]-naphtho[1 ,2-b]pyran; 2-(4-(2-(2- hydroxyethoxy)ethoxy)phenyl)- 2-phenyl-5-methoxycarbonyl-6-(2-(2-methylprop-2- enoxyloxy)ethoxy)-[2H]-naphtho[1 ,2-b]pyran; 3-(4-(2-(2-hydroxyethoxy)- ethoxy)ethoxyphenyl)-3-phenyl-9-methoxycarbonyl-8-methoxy-[3 H]-naptho[1 ,2- b]pyran; 2-(4-morpholinophenyl)-2-phenyl-5-methoxycarbonyl-6-hydroxy- 2H- naphtho[1 ,2-b]pyran; 2-(9-ethylcarbazol-2-yl)-2-phenyl-5-methoxycarbonyl-6- hydroxy-2H-naphtho[1 ,2-b]pyran; 2-(9-phenylcarbazol-2-yl)-2-phenyl-5- methoxycarbonyl-6-hydroxy-2H-naphtho[1 ,2-b]pyran; 2-(4-dimethylaminophenyl)-2- phenyl-5-methoxycarbonyl-6-hydroxy-2H-naphtho[1 ,2-b]pyran; 3-(2-flurophenyl)-3- (4-methoxyphenyl-8-hydroxy-9-carbopropoxy-3H-naphtho[2,1-b]p yran; 3-(2- flurophenyl)-3-(4-methoxyphenyl-8-hydroxy-9-carbomethoxy-3H- naphtho[2,1- b]pyran; 3-(2,4-dimethoxyphenyl)-3-(4-methoxyphenyl-8-hydroxy-9-carbo methoxy- 3H-naphtho[2,1-b]pyran; 3-(2,4,6-triflurophenyl)-3-(2,4,6-trimethoxy-1-naphthyl)-8- acetyl-9-carboniloyl-3H-naphtho[2,1-b]pyran; 3-(4-methoxyphenyl)-3-(2-methyl-2,3- dihydrobenzofur-5-yl)-6-methoxy-12-hydroxymethyl- 11 -phenyl-3H-phenanthro[1 ,2- b]pyran; 5,5-bis(4-methoxyphenyl)-8-methylol-5H-fluorantheno[3,2-b]py ran; or a mixture thereof. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 26 to 28, wherein said at least one reactive photochromic compound comprises 1-hydroxyethyl-3,3-dimethylspiro[indoline-2,3’-[3H]-naphth o[2,1- b][1 ,4]oxazine]; 1-hydroxypropyl-3,3-dimethylspiro[indoline-2,3’-[3H]-napht ho[2,1- b][1 ,4]oxazine]; 1 -aminoethyl-3,3-dimethyl-5-chlorospiro[indoline-2,3’-[3H]- naphtho[2,1 -b][1 ,4]oxazine]; 1 -hydroxyethyl-3,3-dimethyl-8’-methoxyspiro[indoline- 2,3’-[3H]-naphtho[2,1 -b][1 ,4]oxazine]; 1-(p-vinylphenyl)-3,3-dimethyl-5,6- dichlorospiro[indoline-2,3’-[3H]-naphtho[2,1-b][1 ,4]oxazine]; 1 ,3,3-trimethyl-9’- hydroxyspiro[indoline-2,3’-[3H]-naphtho[2,1-b][1 ,4]oxazine]; 1 ,3,3-trimethyl-5’- hydroxymethylspiro[indoline-2,3’-[3H]-naphtho[2,1-b][1 ,4]oxazine]; 1 ,3,3-trimethyl-9’- aminospiro[indoline-2,3’-[3H]-naphtho[2,1-b][1 ,4]oxazine]; 1 ,3,3-trimethyl-5-chloro- 8’-hydroxyspiro[indoline-2,3’-[3H]-naphtho[2,1 -b][1 ,4]oxazine]; 1 -benzyl-3, 3- dimethyl-9’-vinylbenzoyloxyspiro[indoline-2,3’-[3H]-naph tho[2,1 -b][1 ,4]oxazine]; 1 - benzyl-3, 3-dimethyl-5’-hydroxymethylpiperidinospironaphthooxazine; 1 ,3,3- trimethyl-9’-hydroxyspiro[indoline-2,3’-[3H]-pyrido-[2,1 -b][1 ,4]benzooxazine]; 5- hydroxy-6’-cyano-1 ,3,3-trimethyl-spiro-[indoline-2,3’-[3H]-naphtho[2,1- b][1 ,4]oxazine]; 5-hydroxy-6’-phenylsulfonyl-1 ,3,3-trimethyl-spiro-[indoline-2,3’-[3H]- naphtho[2,1 -b][1 ,4]oxazine]; 5’formyl-1 ,3,3-trimethylspiro[indoline-2,3’-[3H]- naphtho[2,1 -b][1 ,4]oxazine; 1 ,3-dihydro-6’-piperazino-1 ,3,3-trimethyl spiro [2H indole-2, 3’-[3H]-naphtho[2,1-b][1 ,4]oxazine; 1 ,3-dihydro-6’-(4- hydroxyethyl)piperazino-1 , 3, 3-trimethyl spiro [2H indole-2, 3’-[3H]-naphtho[2,1 - b][1 ,4]oxazine; 1 ,3-dihydro-9’-hydroxy-1 ,3,3-trimethyl spiro 92H indole-2, 3’-[3H]- naphtho[2,1 -b][1 ,4] oxazine; 1 ,3,3,4,5-pentamethyl-9’-methoxycarbonyl-8’-hydroxy- spiro[indoline-2,3’-[3H]naphth[2,1-b][1 ,4]oxazine; 1 , 3,3,5, 6-pentamethyl-9’- methoxycarbonyl-8’-hydroxy-spiro[indoline-2,3’-[3H]napht h[2,1 -b][1 ,4]oxazine; 1- propyl-3,3,4,5-tetramethyl-9’-methoxycarbonyl-8’-hydroxy -spiro[indoline-2,3’- [3H]naphth[2,1 -b][1 ,4]oxazine; 1-propyl-3,3,5,6-tetramethyl-9’-methoxycarbonyl-8’- hydroxy-spiro[indoline-2,3’-[3H]naphth[2,1-b][1 ,4]oxazine; 1 -methoxyethyl-3,3- dimethyl-9’-allyloxycarbonyl-8’-chloroactoxy-spiro[indol ine-2,3’-[3H]naphth[2,1- b][1 ,4]oxazine; 1 -allyl-3,3-spirocyclohexyl-9’-benzyloxycarbonyl-8’-chlor oactoxy- spiro[indoline-2,3’-[3H]naphth[2,1-b][1 ,4]oxazine; 5-amino-1 ,3,3-trimethyl- spiro[indoline-2,3’-[3H]-pyrido[3,4-f][1 ,4]benzoxazine; 6-hydroxy-1 ’,3’,3’,4’,5’- pentamethylspiro[2H-1 ,4-benzoxazine-2,2’-indoline]; 6-hydroxy-1’,3’,3’,5’,6’- pentamethylspiro[2H-1 ,4-benzoxazine-2,2’-indoline]; 5,7-dimethoxy-1’-hydroxy- carbonylethyl-3’,3’-dimethylspiro[2H-1 ,4-bezoxazine-2,2’-indoline]; 7-methoxy-1’- hydroxy-ethyl-3’,3’-dimethylspiro[2H-1 ,4-bezoxazine-2,2’-indoline]; 9’-hydroxy-1 - methylspiro[indoline-2,3’-(3H)-naphtho(2,1 -b)-1 ,4-oxazine]; 5-chloro-9’-hydroxy-1- methylspiro[indoline-2,3’-(3H)-naphtho(2,1 -b)-1 ,4-oxazine]; 8’-hydroxy-1- methylspiro[indoline-2,3’-(3H)-naphtho(2,1 -b)-1 ,4-oxazine]; 8’-hydroxy-5-methoxy-1 - methylspiro[indoline-2,3’-(3H)-naphtho(2,1 -b)-1 ,4-oxazine]; 8’-hydroxy-1 ,4,5- trimethylspiro[indoline-2,3’-(3H)-naphtho(2,1-b)-1 ,4-oxazine]; 9’-hydroxy-1 - isopropylspiro[indoline-2,3’-(3H)-naphtho(2,1-b)-1 ,4-oxazine]; 9’-hydroxy-1 - hexadecyl-spiro[indoline-2,3’-(3H)-naphtho(2,1-b)-1 ,4-oxazine]; 9’-hydroxy-1- octadecylspiro[indoline-2,3’-(3H)-naphtho(2,1-b)-1 ,4-oxazine]; 1,1”-(1 ,5- pentanediyl)bis[3,3-dimethyl]-9’-hydroxy-spiro[indoline-2, 3’-[3H]-naphtho[2,1-b] [1,4]oxazine]; 1,1”-[1 ,4-phenylenebis(methylene)] bis[3,3-dimethyl]-5’- hydroxymethylspiro[indoline-2,3’-[3H]-naphtho[2,1-b] [1,4]oxazine]; 1 , 1”-(1 ,4- butanediyl)bis[5,6-dichloro-3,3-dimethyl]-8’-hydroxyspiro[ indoline-2,3’-[3H]- naphtho[2,1-b] [1 ,4]oxazine]; 1 ,3,3-trimethyl-9’- hydroxypiperidinospironaphthooxazine; 3-carboxyethyl-1 ,1 -dimethyl-9’- methoxyspiro[benz[e]-indoline-2,3’-[3H]-naphtho[2,1 -b][1 ,4]oxazine]; 1 -carboxyethyl- 3,3-dimethyl-9’-methoxyspiro[benz[g]-indoline-2,3’-[3H]- naphtho[2,1-b][1 ,4]oxazine]; 1 ,1-dimethyl-3-hydroxyethyl-9’-methoxyspiro[benz[e]-indolin e-2,3’-[3H]-naphtho[2,1- b][1 ,4]oxazine]; 3,3-dimethyl-1 -hydroxyethyl-9’-methoxyspiro[benz[g]-indoline-2,3’- [3H]-naphtho[2,1 -b][1 ,4]oxazine]; 3-carboxyethyl-1 ,1 -dimethyl-9’- methoxyspiro[benz[e]-indoline-2,3’-[3H]-pyrido[2,1 -b][1 ,4]benzoxazine]; 1 - carboxyethyl-3,3-dimethyl-9’-methoxyspiro[benz[g]-indoline -2,3’-[3H]-pyrido[2,1- b][1 ,4]benzoxazine]; 1 ,1 -dimethyl-3-hydroxyethyl-9’-methoxyspiro[benz[e]-indoline- 2,3’-[3H]-pyrido[2,1-b][1,4]benzoxazine]; 3,3-dimethyl-1-hydroxyethyl-9’- methoxyspiro[benz[g]-indoline-2,3’-[3H]-pyrido[2,1 -b][1 ,4]benzoxazine]; 5-amino-5’- (2-benzthiazolyl)-1 ,3,3-trimethylspiro[indoline-2,3’-[3H]-naphtho[2,1 -b][1 ,4]oxazine]; 5-amino-5’-(5’-(2-hydroxyphenyl)-2-oxadiazolyl)-1 -isopropyl-3, 3- dimethylspiro[indoline-2,3’-[3H]-naphtho[2,1-b][1 ,4]oxazine]; 5-amino-5’-(5’-phenyl- 2-oxadiazolyl)-1 ,3,3-trimethylspiro[indoline-2,3’-[3H]-naphtho[2,1 -b][1 ,4]oxazine]; or a mixture thereof. The photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 26 to 29, wherein said at least one reactive photochromic compound comprises 3,3-bis(4-methoxyphenyl)-6,11-dimethyl-13-hydroxyethoxy-13-p henyl- 3H,13H-indeno [2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-bis(4-methoxyphenyl)-6,11- dimethyl-13-(2-hydroxycarbonylethyl)carboxyethoxy-13-phenyl- 3H,13H-indeno [2’,3’:3,4]naphtho[1,2-b]pyran; 3,3-bis(4-methoxyphenyl)-6,11 -dimethyl- 13-hydroxy- 13-phenyl-3H,13H-indeno [2’,3’:3,4]naphtho[1,2-b]pyran; or a mixture thereof. A soft photochromic contact lens, comprising a crosslinked polymeric material that comprises units of a photochromic polydiorganosiloxane vinylic crosslinker of any one of embodiments 1 to 30. The soft photochromic contact lens of embodiment 31 , which is a photochromic silicone hydrogel contact lens comprising a silicone hydrogel material as bulk material. The soft photochromic contact lens of embodiment 32, wherein the photochromic silicone hydrogel contact lens, when being fully hydrated, has an oxygen permeability (Dk) of at least about 40 barrers, a water content of from about 15% to about 70% by weight, an elastic modulus of from about 0.20 MPa to about 1 .8 MPa. The soft photochromic contact lens of embodiment 32 or 33, wherein the photochromic silicone hydrogel contact lens, when being fully hydrated, has an oxygen permeability (Dk) of at least about 60 barrers. The soft photochromic contact lens of embodiment 32 or 33, wherein the photochromic silicone hydrogel contact lens, when being fully hydrated, has an oxygen permeability (Dk) of at least about 70 barrers. The soft photochromic contact lens of embodiment 32 or 33, wherein the photochromic silicone hydrogel contact lens, when being fully hydrated, has an oxygen permeability (Dk) of at least about 80 barrers. The soft photochromic contact lens of any one of embodiments 32 to 36, wherein the photochromic silicone hydrogel contact lens, when being fully hydrated, has a water content of from about 20% to about 70% by weight. The soft photochromic contact lens of any one of embodiments 32 to 36, wherein the photochromic silicone hydrogel contact lens, when being fully hydrated, has a water content of from about 25% to about 65% by weight. The soft photochromic contact lens of any one of embodiments 32 to 36, wherein the photochromic silicone hydrogel contact lens, when being fully hydrated, has a water content of from about 30% to about 60% by weight. The soft photochromic contact lens of any one of embodiments 32 to 39, wherein the photochromic silicone hydrogel contact lens, when being fully hydrated, has an elastic modulus of from about 0.25 MPa to about 1 .5 MPa. The soft photochromic contact lens of any one of embodiments 32 to 39, wherein the photochromic silicone hydrogel contact lens, when being fully hydrated, has an elastic modulus of from about 0.3 MPa to about 1.2 MPa. The soft photochromic contact lens of any one of embodiments 32 to 39, wherein the photochromic silicone hydrogel contact lens, when being fully hydrated, has an elastic modulus of from about 0.4 MPa to about 1.0 MPa. The soft photochromic contact lens of any one of embodiments 32 to 42, wherein the photochromic silicone hydrogel contact lens comprises units of at least one silicone-containing polymerizable component and units of at least one hydrophilic vinylic monomer. The soft photochromic contact lens of any one of embodiments 32 to 43, wherein the silicone hydrogel contact material comprises repeating units of at least one silicone-containing vinylic monomer selected from the group consisting of a vinylic monomer having a bis(trialkylsilyloxy)alkylsilyl group, a vinylic monomer having a tris(trialkylsilyloxy)silyl group, a polysiloxane vinylic monomer, 3-methacryloxy propylpentamethyldisiloxane, t-butyldimethyl-siloxyethyl vinyl carbonate, trimethylsilylethyl vinyl carbonate, and trimethylsilylmethyl vinyl carbonate, and combinations thereof. The soft photochromic contact lens of any one of embodiments 32 to 43, wherein the silicone hydrogel contact material comprises repeating units of at least one silicone-containing vinylic monomer of formula (M1 ) or (M2) in which: aMi is zero or 1 ; RMO is H or methyl; X _M o is O or NR _M1 ; L _M1 is a C2-C8 alkylene divalent radical or a divalent radical of ; L M1’ is a C2-C8 alkylene divalent radical which has zero or one hydroxyl group; L _M1 ” is C3-C8 alkylene divalent radical which has zero or one hydroxyl group; XMI is O, NR _M 1, NHCOO, OCONH, CONRMI, or NRMICO; RMI is H or a C ₁ -C ₄ alkyl having 0 to 2 hydroxyl group; Rn and R _t 2 independent of each other are a C1-C6 alkyl; X _M1 ’ is O or NRi; v1 is an integer of 1 to 30; m2 is an integer of 0 to 30; n1 is an integer of 3 to 40; and r1 is an integer of 2 or 3. The soft photochromic contact lens of embodiment 44 or 45, wherein said at least one silicone-containing vinylic monomer comprises tris(trimethylsilyloxy)silylpropyl (meth)acrylate, [3-(meth)acryloxy-2- hydroxypropyloxy]propylbis(trimethylsiloxy)methylsilane, [3-(meth)acryloxy-2- hydroxypropyloxy]propylbis(trimethylsiloxy)butylsilane, 3-(meth)acryloxy-2-(2- hydroxyethoxy)-propyloxy)propylbis(trimethylsiloxy)methylsil ane, 3-(meth)acryloxy- 2-hydroxypropyloxy)propyltris(trimethylsiloxy)silane, N- [tris(trimethylsiloxy)silylpropyl]-(meth)acrylamide, N-(2-hydroxy-3-(3- (bis(trimethylsilyloxy)methylsilyl)propyloxy)propyl)-2-methy l (meth)acrylamide, N-(2- hydroxy-3-(3-(bis(trimethylsilyloxy)methylsilyl)propyloxy)-p ropyl) (meth)acrylamide, N-(2-hydroxy-3-(3-(tris(trimethylsilyloxy)silyl)propyloxy)pr opyl)-2-methyl acrylamide, N-(2-hydroxy-3-(3-(tris(trimethylsilyloxy)silyl)propyloxy)pr opyl) (meth)acrylamide, N- [tris(dimethylpropylsiloxy)silylpropyl]-(meth)acrylamide, N-

[tris(dimethylphenylsiloxy)-silylpropyl] (meth)acrylamide, N-[tris(dimethylethylsiloxy)- silylpropyl] (meth)acrylamide, N,N-bis[2-hydroxy-3-(3-

(bis(trimethylsilyloxy)methylsilyl)-propyloxy)propyl]-2-m ethyl (meth)acrylamide, N,N- bis[2-hydroxy-3-(3-(bis(trimethylsilyloxy)methylsilyl)propyl oxy)-propyl] (meth)acrylamide, N,N-bis[2-hydroxy-3-(3-(tris(trimethylsilyloxy)silyl)propylo xy)- propyl]-2-methyl (meth)acrylamide, N,N-bis[2-hydroxy-3-(3- (tris(trimethylsilyloxy)silyl)-propyloxy)propyl] (meth)acrylamide, N-[2-hydroxy-3-(3-(t- butyldimethylsilyl)propyloxy)-propyl]-2-methyl (meth)acrylamide, N-[2-hydroxy-3-(3- (t-butyldimethylsilyl)propyloxy)-propyl] (meth)acrylamide, N,N-bis[2-hydroxy-3-(3-(t- butyldimethylsilyl)propyloxy)propyl]-2-methyl (meth)acrylamide, N-2- (meth)acryloxyethyl-0-(methyl-bis-trimethylsiloxy-3-propyl)s ilyl carbamate, 3- (trimethylsilyl)propylvinyl carbonate, 3-(vinyloxycarbonylthio)-propyl-tris(trimethyl- siloxy)silane, 3-[tris(trimethylsiloxy)silyl]propylvinyl carbamate, 3- [tris(trimethylsiloxy)silyl] propyl allyl carbamate, 3-[tris(trimethylsiloxy)silyl]propyl vinyl carbonate, or a combination thereof. The soft photochromic contact lens of any one of embodiments 44 to 46, wherein said at least one silicone-containing vinylic monomer comprises a- (meth)acryloxypropyl terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a- (meth)acryloxy-2-hydroxypropyloxypropyl terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-(2-hydroxyl-methacryloxypropyloxypropyl)-ω -C1-C ₄ -alkyl- decamethylpentasiloxane, a-[3-(meth)acryloxyethoxy-2-hydroxypropyloxypropyl]- terminated ω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-[3-(meth)acryloxy- propyloxy-2-hydroxypropyloxypropyl]-terminated ω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-[3-(meth)acryloxyisopropyloxy-2-hydroxypropyloxypropyl]- terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-[3- (meth)acryloxybutyloxy-2-hydroxypropyloxypropyl]-terminateω d-C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-[3-(meth)acryloxyethylamino-2- hydroxypropyloxypropyl]-terminateωd -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-[3-(meth)acryloxypropylamino-2-hydroxypropyloxypropyl]-ter minateωd-C ₁ -C ₄ - alkyl terminated polydimethylsiloxane, a-[3-(meth)acryloxy-butylamino-2- hydroxypropyloxypropyl]-terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-(meth)acryloxy(polyethylenoxy)-2-hydroxypropyloxypropyl]-t erminated ω -C1-C4- alkyl terminated polydimethylsiloxane, a-[(meth)acryloxy-2-hydroxypropyloxy- ethoxypropyl]-terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a- [(meth)acryloxy-2-hydroxypropyl-N-ethylaminopropyl]-terminat ed ω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-[(meth)acryloxy-2-hydroxypropyl-aminopropyl]- terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-[(meth)acryloxy-2- hydroxypropyloxy-(polyethylenoxy)propyl]-terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-(meth)acryloylamidopropyloxypropyl terminated ω -C1 -04- alkyl terminated polydimethylsiloxane, a-N-methyl- (meth)acryloylamidopropyloxypropyl terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-[3-(meth)acrylamidoethoxy-2-hydroxypropyloxy-propyl]- terminatedω -C ₁ -C ₄ -alkyl polydimethylsiloxane, a-[3-(meth)acrylamidopropyloxy-2- hydroxypropyloxypropyl]-terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-[3-(meth)acrylamidoisopropyloxy-2-hydroxypropyloxypropyl]- terminated ω -C1-C4- alkyl terminated polydimethylsiloxane, a-[3-(meth)acrylamidobutyloxy-2- hydroxypropyloxypropyl]-terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, a-[3-(meth)acryloylamido-2-hydroxypropyloxypropyl] terminatedω -C ₁ -C ₄ -alkyl polydimethylsiloxane, a-[3-[N-methyl-(meth)acryloylamido]-2- hydroxypropyloxypropyl] terminatedω -C ₁ -C ₄ -alkyl terminated polydimethylsiloxane, N-methyl-N'-(propyltetra(dimethylsiloxy)dimethylbutylsilane) (meth)acrylamide, N- (2,3-dihydroxypropane)-N'-(propyltetra(dimethylsiloxy)dimeth ylbutylsilane) (meth)acrylamide,

(meth)acryloylamidopropyltetra(dimethylsiloxy)dimethylbut ylsilane, a-vinyl carbonate-terminated ω -C ₁ -C ₄ -alkyl-terminated polydimethylsiloxanes, a-vinyl carbamate-terminated ω -C ₁ -C ₄ -alkyl-terminated polydimethylsiloxane, or a mixture thereof. The soft photochromic contact lens of any one of embodiments 32 to 47, wherein the silicone hydrogel material comprises repeating units of at least one polysiloxane vinylic crosslinker. The soft photochromic contact lens of embodiment 48, wherein said at least one polysiloxane vinylic crosslinker comprises a di-(meth)acryloyl-terminated polydimethylsiloxane, a di-vinyl carbonate-terminated polydimethylsiloxane; a di- vinyl carbamate-terminated polydimethylsiloxane; N,N,N',N'-tetrakis(3-methacryloxy- 2-hydroxypropyl)-alpha,omega-bis-3-aminopropyl-polydimethyls iloxane, or a combination thereof.

The soft photochromic contact lens of embodiment 48 or 49, wherein said at least one polysiloxane vinylic crosslinker comprises a vinylic crosslinker of formula (I) in which: d1 is an integer of from 30 to 500 and d2 is an integer of from 1 to 75, provided that d2/d1 is from about 0.035 to about 0.15 (preferably from about 0.040 to about 0.12, even more preferably from about 0.045 to about 0.10);

X01 is O or NR _IN in which R _|N is hydrogen or CrCio-alkyl;

Rio is hydrogen or methyl;

Rii and R12 independently of each other are a substituted or unsubstituted C1-C10 alkylene divalent radical or a divalent radical of -R14-O-R15- in which R _w and R _I5 independently of each other are a substituted or unsubstituted C1-C10 alkylene divalent radical;

Ri3 is a monovalent radical of any one of formula (la) to (le) k1 is zero or 1 ; ml is an integer of 2 to 4; m2 is an integer of 1 to 5; m3 is an integer of 3 to 6; m4 is an integer of 2 to 5;

Ri ₆ is hydrogen or methyl;

Ri7 is a C2-C6 hydrocarbon radical having (m2+1) valencies;

R _I8 is a C2-C6 hydrocarbon radical having (m4+1) valencies;

Rig is ethyl or hydroxymethyl;

R110 is methyl or hydromethyl;

R ₁₁₁ is hydroxyl or methoxy; is a sulfur linkage of -S- or a teriary amino linkage of in which is C1-C1 alkyl, hydroxyethyl, hydroxypropyl, or 2,3-dihydroxypropyl; and

X12 is an amide linkage of in which R113 is hydrogen or C1-C10 alkyl. The soft photochromic contact lens of any one embodiments 48 to 50, wherein said at least one polysiloxane vinylic crosslinker comprises: (1) a vinylic crosslinker which comprises one sole polydiorganosiloxane segment and two terminal ethylenically-unsaturated groups selected from the group consisting of (meth)acryloyloxy groups, (meth)acryloylamino groups, vinyl carbonate groups, vinylcarbamate groups; and/or (2) a chain-extended polysiloxane vinylic crosslinker which comprises at least two polydiorganosiloxane segment and a covalent linker between each pair of polydiorganosiloxane segments and two two terminal ethylenically-unsaturated groups selected from the group consisting of (meth)acryloyloxy groups, (meth)acryloylamino groups, vinyl carbonate groups, vinylcarbamate groups. The soft photochromic contact lens of any one embodiments 48 to 51 , wherein said at least one polysiloxane vinylic crosslinker comprises a,w-bis[3- (meth)acrylamidopropyl]-terminated polydimethylsiloxane, a,ω -bis[3- (meth)acryloxypropyl]-terminated polydimethylsiloxane, a,ω -bis[3-(meth)acryloxy-2- hydroxypropyloxypropyl]-terminated polydimethylsiloxane, a,ω -bis[3- (meth)acryloxyethoxy-2-hydroxypropyloxypropyl]-terminated polydimethylsiloxane, α, ω -bis[3-(meth)acryloxypropyloxy-2-hydroxypropyloxypropyl]-ter minated polydimethylsiloxane, α, ω -bis[3-(meth)acryloxy-isopropyloxy-2- hydroxypropyloxypropyl]-terminated polydimethylsiloxane, a,ω -bis[3- (meth)acryloxybutyloxy-2-hydroxypropyloxypropyl]-terminated polydimethylsiloxane, α, ω -bis[3-(meth)acrylamidoethoxy-2-hydroxypropyloxypropyl]-term inated polydimethylsiloxane, α, ω -bis[3-(meth)acrylamidopropyloxy-2- hydroxypropyloxypropyl]-terminated polydimethylsiloxane, a,ω-bis[3- (meth)acrylamidoisopropyloxy-2-hydroxypropyloxypropyl]-termi nated polydimethylsiloxane, α, ω -bis[3-(meth)acrylamidobutyloxy-2- hydroxypropyloxypropyl]-terminated polydimethylsiloxane, a,ω -bis[3- (meth)acryloxyethylamino-2-hydroxypropyloxypropyl]-terminate d polydimethylsiloxane, α, ω -bis[3-(meth)acryloxypropylamino-2- hydroxypropyloxypropyl]-terminated polydimethylsiloxane, a,ω -bis[3- (meth)acryloxybutylamino-2-hydroxypropyloxypropyl]-terminate d polydimethylsiloxane, α, ω -bis[(meth)acrylamidoethylamino-2-hydroxypropyloxy- propyl]-terminated polydimethylsiloxane, α, ω -bis[3-(meth)acrylamidopropylamino-2- hydroxypropyloxypropyl]-terminated polydimethylsiloxane, α, ω -bis[3- (meth)acrylamide-butylamino-2-hydroxypropyloxypropyl]-termin ated polydimethylsiloxane, α, ω -bis[(meth)acryloxy-2-hydroxypropyloxy-ethoxypropyl]- terminated polydimethylsiloxane, α, ω -bis[(meth)acryloxy-2-hydroxypropyl-N- ethylaminopropyl]-terminated polydimethylsiloxane, α, ω -bis[(meth)acryloxy-2- hydroxypropyl-aminopropyl]-polydimethylsiloxane, α, ω -bis[(meth)acryloxy-2- hydroxypropyloxy-(polyethylenoxy)propyl]-terminated polydimethylsiloxane, a,w- bis[(meth)acryloxyethylamino-carbonyloxy-ethoxypropyl]-termi nated polydimethylsiloxane, α, ω -bis[(meth)acryloxyethylamino-carbonyloxy- (polyethylenoxy)propyl]-terminated polydimethylsiloxane, or combinations thereof. The soft photochromic contact lens of any one embodiments 32 to 52, wherein the silicone hydrogel material comprises repeating units of at least one hydrophilic vinylic monomer. The soft photochromic contact lens of embodiment 53, wherein said at least one hydrophilic vinylic monomer comprises: (1) an alkyl (meth)acrylamide selected from the group consisting of (meth)acrylamide, N,N-dimethyl (meth)acrylamide, N-ethyl (meth)acrylamide, N,N-diethyl (meth)acrylamide, N-propyl (meth)acrylamide, N- isopropyl (meth)acrylamide, N-3-methoxypropyl (meth)acrylamide, and combinations thereof; (2) a hydroxyl-containing acrylic monomer selected from the group consisting of N-2-hydroxylethyl (meth)acrylamide, N,N-bis(hydroxyethyl) (meth)acrylamide, N-3-hydroxypropyl (meth)acrylamide, N-2-hydroxypropyl (meth)acrylamide, N-2,3-dihydroxypropyl (meth)acrylamide, N- tris(hydroxymethyl)methyl (meth)acrylamide, 2-hydroxyethyl (meth)acrylate, 3- hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, glycerol methacrylate (GMA), di(ethylene glycol) (meth)acrylate, tri(ethylene glycol) (meth)acrylate, tetra(ethylene glycol) (meth)acrylate, poly(ethylene glycol) (meth)acrylate having a number average molecular weight of up to 1500, polyethylene glycol)ethyl (meth)acrylamide having a number average molecular weight of up to 1500, and combinations thereof; (3) a carboxyl-containing acrylic monomer selected from the group consisting of 2-(meth)acrylamidoglycolic acid, (meth)acrylic acid, ethylacrylic acid, 3-(emth)acrylamidopropionic acid, 5- (meth)acrylamidopentanoic acid, 4-(meth)acrylamidobutanoic acid, 3- (meth)acrylamido-2-methylbutanoic acid, 3-(meth)acrylamido-3-methylbutanoic acid, 2-(emth)acrylamido-2methyl — 3,3-dimethyl butanoic acid, 3- (meth)acrylamidohaxanoic acid, 4-(meth)acrylamido-3,3-dimethylhexanoic acid, and combinations thereof; (4) an amino-containing acrylic monomer selected from the group consisting of N-2-aminoethyl (meth)acrylamide, N-2-methylaminoethyl (meth)acrylamide, N-2-ethylaminoethyl (meth)acrylamide, N-2-dimethylaminoethyl (meth)acrylamide, N-3-aminopropyl (meth)acrylamide, N-3-methylaminopropyl (meth)acrylamide, N-3-dimethylaminopropyl (meth)acrylamide, 2-aminoethyl (meth)acrylate, 2-methylaminoethyl (meth)acrylate, 2-ethylaminoethyl (meth)acrylate, 3-aminopropyl (meth)acrylate, 3-methylaminopropyl (meth)acrylate,

3-ethylaminopropyl (meth)acrylate, 3-amino-2-hydroxypropyl (meth)acrylate, trimethylammonium 2-hydroxy propyl (meth)acrylate hydrochloride, dimethylaminoethyl (meth)acrylate, and combinations thereof; (5) an N-vinyl amide monomer selected from the group consisting of N-vinylpyrrolidone (aka, N-vinyl-2- pyrrolidone), N-vinyl-3-methyl-2-pyrrolidone, N-vinyl-4-methyl-2-pyrrolidone, N-vinyl- 5-methyl-2-pyrrolidone, N-vinyl-6-methyl-2-pyrrolidone, N-vinyl-3-ethyl-2- pyrrolidone, N-vinyl-4,5-dimethyl-2-pyrrolidone, N-vinyl-5,5-dimethyl-2- pyrrolidone, N-vinyl-3,3,5-trimethyl-2-pyrrolidone, N-vinyl piperidone (aka, N-vinyl-2- piperidone), N-vinyl-3-methyl-2-piperidone, N-vinyl-4-methyl-2-piperidone, N-vinyl- 5-methyl-2-piperidone, N-vinyl-6-methyl-2-piperidone, N-vinyl-6-ethyl-2-piperidone, N-vinyl-3,5-dimethyl-2-piperidone, N-vinyl-4,4-dimethyl-2-piperidone, N-vinyl caprolactam (aka, N-vinyl-2-caprolactam), N-vinyl-3-methyl-2-caprolactam, N-vinyl-

4-methyl-2-caprolactam, N-vinyl-7-methyl-2-caprolactam, N-vinyl-7-ethyl-2- caprolactam, N-vinyl-3,5-dimethyl-2-caprolactam, N-vinyl-4,6-dimethyl-2- caprolactam, N-vinyl-3,5,7-trimethyl-2-caprolactam, N-vinyl-N-methyl acetamide, N- vinyl formamide, N-vinyl acetamide, N-vinyl isopropylamide, N-vinyl-N-ethyl acetamide, N-vinyl-N-ethyl formamide, and mixtures thereof; (6) a methylene- containing pyrrolidone monomer selected from the group consisting of 1-methyl-3- methylene-2-pyrrolidone, 1 -ethyl-3-methylene-2-pyrrolidone, 1 -methyl-5-methylene- 2-pyrrolidone, 1 -ethyl-5-methylene-2-pyrrolidone, 5-methyl-3-methylene-2- pyrrolidone, 5-ethyl-3-methylene-2-pyrrolidone, 1 -n-propyl-3-methylene-2- pyrrolidone, 1 -n-propyl-5-methylene-2-pyrrolidone, 1 -isopropyl-3-methylene-2- pyrrolidone, 1 -isopropyl-5-methylene-2-pyrrolidone, 1 -n-butyl-3-methylene-2- pyrrolidone, 1-tert-butyl-3-methylene-2-pyrrolidone, and combinations thereof; (7) an acrylic monomer having a C1-C4 alkoxyethoxy group and selected from the group consisting of ethylene glycol methyl ether (meth)acrylate, di(ethylene glycol) methyl ether (meth)acrylate, tri(ethylene glycol) methyl ether (meth)acrylate, tetra(ethylene glycol) methyl ether (meth)acrylate, CrC4-alkoxy poly(ethylene glycol) (meth)acrylate having a number average molecular weight of up to 1500, methoxy- poly(ethylene glycol)ethyl (meth)acrylamide having a number average molecular weight of up to 1500, and combinations thereof; (8) a vinyl ether monomer selected from the group consisting of ethylene glycol monovinyl ether, di(ethylene glycol) monovinyl ether, tri(ethylene glycol) monovinyl ether, tetra(ethylene glycol) monovinyl ether, polyethylene glycol) monovinyl ether, ethylene glycol methyl vinyl ether, di(ethylene glycol) methyl vinyl ether, tri(ethylene glycol) methyl vinyl ether, tetra(ethylene glycol) methyl vinyl ether, polyethylene glycol) methyl vinyl ether, and combinations thereof; (9) an allyl ether monomer selected from the group consisting of ethylene glycol monoallyl ether, di(ethylene glycol) monoallyl ether, tri(ethylene glycol) monoallyl ether, tetra(ethylene glycol) monoallyl ether, polyethylene glycol) monoallyl ether, ethylene glycol methyl allyl ether, di(ethylene glycol) methyl allyl ether, tri(ethylene glycol) methyl allyl ether, tetra(ethylene glycol) methyl allyl ether, polyethylene glycol) methyl allyl ether, and combinations thereof; (10) a phosphorylcholine-containing vinylic monomer selected from the group consisting of (meth)acryloyloxyethyl phosphorylcholine, (meth)acryloyloxypropyl phosphorylcholine, 4-((meth)acryloyloxy)butyl-2'-(trimethylammonio)ethylphospha te, 2-[(meth)acryloylamino]ethyl-2 ^, -(trimethylammonio)-ethylphosphate, 3- [(meth)acryloylamino]propyl-2'-(trimethylammonio)ethylphosph ate, 4- [(meth)acryloylamino]butyl-2 ^, -(trimethylammonio)ethylphosphate, 5- ((meth)acryloyloxy)pentyl-2'-(trimethylammonio)ethyl phosphate, 6- ((meth)acryloyloxy)hexyl-2'-(trimethylammonio)-ethylphosphat e, 2- ((meth)acryloyloxy)ethyl-2’-(triethylammonio)ethylphosphat e, 2- ((meth)acryloyloxy)ethyl-2'-(tripropylammonio)ethylphosphate , 2- ((meth)acryloyloxy)ethyl-2'-(tributylammonio)ethyl phosphate, 2- ((meth)acryloyloxy)propyl-2'-(trimethylammonio)-ethylphospha te, 2- ((meth)acryloyloxy)butyl-2'-(trimethylammonio)ethylphosphate , 2- ((meth)acryloyloxy)pentyl-2'-(trimethylammonio)ethylphosphat e, 2- ((meth)acryloyloxy)hexyl-2'-(trimethylammonio)ethyl phosphate, 2-(vinyloxy)ethyl-2'- (trimethylammonio)ethylphosphate, 2-(allyloxy)ethyl-2'- (trimethylammonio)ethylphosphate, 2-(vinyloxycarbonyl)ethyl-2'- (trimethylammonio)ethyl phosphate, 2-(allyloxycarbonyl)ethyl-2'- (trimethylammonio)-ethylphosphate, 2-(vinylcarbonylamino)ethyl-2 ^, - (trimethylammonio)ethylphosphate, 2-(allyloxycarbonylamino)ethyl-2'- (trimethylammonio)ethyl phosphate, 2-(butenoyloxy)ethyl-2’- (trimethylammonio)ethylphosphate, and combinations thereof; (11) allyl alcohol; (12) N-2-hydroxyethyl vinyl carbamate; (13) N-carboxyvinyl-β -alanine (VINAL); (14) N- carboxyvinyl-a-alanine; (15) or combinations thereof. The soft photochromic contact lens of embodiment 53 or 54, wherein said at least one hydrophilic vinylic monomer comprises N-vinylpyrrolidone, N-vinyl-N-methyl acetamide, or combinations thereof. The soft photochromic contact lens of any one of embodiments 53 to 55, wherein said at least one hydrophilic vinylic monomer comprises N,N-dimethyl (meth)acrylamide. The soft photochromic contact lens of any one of embodiments 53 to 56, wherein said at least one hydrophilic vinylic monomer comprises N-2-hydroxylethyl (meth)acrylamide, N,N-bis(hydroxyethyl) (meth)acrylamide, N-3-hydroxypropyl (meth)acrylamide, N-2-hydroxypropyl (meth)acrylamide, N-2,3-dihydroxypropyl (meth)acrylamide, N-tris(hydroxymethyl)methyl (meth)acrylamide, 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, glycerol methacrylate (GMA), di(ethylene glycol) (meth)acrylate, tri(ethylene glycol) (meth)acrylate, tetra(ethylene glycol) (meth)acrylate, poly(ethylene glycol) (meth)acrylate having a number average molecular weight of up to 1500, polyethylene glycol)ethyl (meth)acrylamide having a number average molecular weight of up to 1500, or combinations thereof. The soft photochromic contact lens of any one of embodiments 32 to 57, wherein the silicone hydrogel material comprises repeating units of at least one non-silicone vinylic cross-linking agent. The soft photochromic contact lens of embodiment 58, wherein said at least one non-silicone vinylic crossling agent comprises ethyleneglycol di-(meth)acrylate, diethyleneglycol di-(meth)acrylate, triethyleneglycol di-(meth)acrylate, tetraethyleneglycol di-(meth)acrylate, glycerol di-(meth)acrylate, 1 ,3-propanediol di- (meth)acrylate, 1 ,3-butanediol di-(meth)acrylate, 1 ,4-butanediol di-(meth)acrylate, glycerol 1 ,3-diglycerolate di-(meth)acrylate, ethylenebis[oxy(2-hydroxypropane-1 ,3- diyl)] di-(meth)acrylate, bis[2-(meth)acryloxyethyl] phosphate, trimethylolpropane di- (meth)acrylate, and 3,4-bis[(meth)acryloyl]tetrahydrofuan, diacrylamide, dimethacrylamide, N,N-di(meth)acryloyl-N-methylamine, N,N-di(meth)acryloyl-N- ethylamine, N,N’-methylene bis(meth)acrylamide, N,N’-ethylene bis(meth)acrylamide, N,N’-dihydroxyethylene bis(meth)acrylamide, N,N’-propylene bis(meth)acrylamide, N,N’-2-hydroxypropylene bis(meth)acrylamide, N,N’-2,3- dihydroxybutylene bis(meth)acrylamide, 1 ,3-bis(meth)acrylamidepropane-2-yl dihydrogen phosphate, piperazine diacrylamide, tetraethyleneglycol divinyl ether, triethyleneglycol divinyl ether, diethyleneglycol divinyl ether, ethyleneglycol divinyl ether, triallyl isocyanurate, triallyl cyanurate, trimethylopropane trimethacrylate, pentaerythritol tetramethacrylate, bisphenol A dimethacrylate, allylmethacrylate, allylacrylate, N-allyl-methacrylamide, N-allyl-acrylamide, or combinations thereof. The soft photochromic contact lens of any one of embodiments 32 to 59, wherein the silicone hydrogel material comprises repeating units of at least one blending vinylic monomer. The soft photochromic contact lens of embodiment 60, wherein said at least one blending vinylic monomer comprises C1-C10 alkyl (meth)acrylate, cyclopentylacrylate, cyclohexylmethacrylate, cyclohexylacrylate, isobornyl (meth)acrylate, styrene, 4,6-trimethylstyrene (TMS), t-butyl styrene (TBS), trifluoroethyl (meth)acrylate, hexafluoro-isopropyl (meth)acrylate, hexafluorobutyl (meth)acrylate, or combinations thereof. The soft photochromic contact lens of embodiment 60 or 61 , wherein said at least one blending vinylic monomer comprises methyl methacrylate. The soft photochromic contact lens of any one of embodiments 32 to 62, wherein the silicone hydrogel material comprises repeating units of at least one UV- absorbing vinylic monomer and/or repeating units of at least one UV/HEVL- Absorbing vinylic monomer. The soft photochromic contact lens of any one of embodiments 32 to 62, wherein the silicone hydrogel material comprises repeating units of 2-[2'-hydroxy-5'-(2- methacryloxyethyl)phenyl)]-2H-benzotriazole (Norbloc), and repeating untis of at least one UV/HEVL absorbing vinylic monomer which is 2-{2’-Hydroxy-3’-tert-butyl- 5’-[3’-methacryloyloxypropoxy]phenyl}-2H-benzotriazole, 2-{2’-Hydroxy-3’-tert-butyl- 5’-[3’-methacryloyloxypropoxy]phenyl}-5-methoxy-2H-benzo triazole (UV13), 2-{2’- Hydroxy-3’-tert-butyl-5’-[3’-methacryloyloxypropoxy]ph enyl}-5-chloro-2H- benzotriazole (UV28), 2-[2’-Hydroxy-3’-tert-butyl-5’-(3’-acryloyloxypropox y)phenyl]- 5-trifluoromethyl-2H-benzotriazole (UV23), or combinations thereof. The soft photochromic contact lens of any one of embodiments 32 to 64, wherein the readily-usable silicone hydrogel contact lens has a UVB transmittance of about 10% or less between 280 and 315 nanometers, a UVA transmittance of about 30% or less between 315 and 380 nanometers, and a Violet transmittance of about 70% or less, preferably about 60% or less, more preferably about 50% or less, even more preferably about 40% or less) between 380 nm and 440 nm. The soft photochromic contact lens of embodiment 65, wherein the readily-usable silicone hydrogel contact lens has a UVB transmittance of about 5% or less between 280 and 315 nanometers. 67. The soft photochromic contact lens of embodiment 65, wherein the readily-usable silicone hydrogel contact lens has a UVB transmittance of about 2.5% or less between 280 and 315 nanometers.

68. The soft photochromic contact lens of embodiment 65, wherein the readily-usable silicone hydrogel contact lens has a UVB transmittance of about 1% or less between 280 and 315 nanometers.

69. The soft photochromic contact lens of any one of embodiments 65 to 68, wherein the readily-usable silicone hydrogel contact lens has a UVA transmittance of about 20% or less between 315 and 380 nanometers.

70. The soft photochromic contact lens of any one of embodiments 65 to 68, wherein the readily-usable silicone hydrogel contact lens has a UVA transmittance of about 10% or less between 315 and 380 nanometers.

71 . The soft photochromic contact lens of any one of embodiments 65 to 68, wherein the readily-usable silicone hydrogel contact lens has a UVA transmittance of about 5% or less between 315 and 380 nanometers.

72. The ophthalmic product of any one of embodiments 65 to 71 , wherein the readily- usable silicone hydrogel contact lens has a Violet transmittance of about 60% or less between 380 nm and 440 nm.

73. The ophthalmic product of any one of embodiments 65 to 71 , wherein the readily- usable silicone hydrogel contact lens has a Violet transmittance of about 50% or less between 380 nm and 440 nm.

74. The ophthalmic product of any one of embodiments 65 to 71 , wherein the readily- usable silicone hydrogel contact lens has a Violet transmittance of about 40% or less between 380 nm and 440 nm.

The previous disclosure will enable one having ordinary skill in the art to practice the invention. Various modifications, variations, and combinations can be made to the various embodiment described herein. In order to better enable the reader to understand specific embodiments and the advantages thereof, reference to the following examples is suggested. It is intended that the specification and examples be considered as exemplary

Example 1

Oxygen Permeability Measurements

Unless specified, the oxygen transmissibility (Dk /t), the intrinsic (or edge- corrected) oxygen permeability (Dk _i or Dk _c ) of a lens and a lens material are determined according to procedures described in ISO 18369-4. Equilibrium Water Content

The equilibrium water content (EWC) of contact lenses are determined as follows.

Amount of water (expressed as percent by weight) present in a hydrated hydrogel contact lens, which is fully equilibrated in saline solution, is determined at room temperature. Quickly stack the lenses, and transfer the lens stack to the aluminum pan on the analytical balance after blotting lens in a cloth. The number of lenses for each sample pan is typically five (5). Record the pan plus hydrated weight of the lenses. Cover the pan with aluminum foil. Place pans in a laboratory oven at 100±2 °C to dry for 16-18 hours. Remove pan plus lenses from the oven and cool in a desiccator for at least 30 minutes. Remove a single pan from the desiccator, and discard the aluminum foil. Weigh the pan plus dried lens sample on an analytical balance. Repeat for all pans. The wet and dry weight of the lens samples can be calculated by subtracting the weight of the empty weigh pan.

Elastic Modulus

The elastic modulus of a contact lens is determined using a MTS insight instrument. The contact lens is first cut into a 3.12 mm wide strip using Precision Concept two stage cutter. Five thickness values are measured within 6.5mm gauge length. The strip is mounted on the instrument grips and submerged in PBS (phosphate buffered saline) with the temperature controlled at 21 ± 2 °C. Typically 5N Load cell is used for the test. Constant force and speed is applied to the sample until the sample breaks. Force and displacement data are collected by the TestWorks software. The elastic modulus value is calculated by the TestWorks software which is the slope or tangent of the stress vs. strain curve near zero elongation, in the elastic deformation region.

Transmittance

Contact lenses are manually placed into a specially fabricated sample holder or the like which can maintain the shape of the lens as it would be when placing onto eye. This holder is then submerged into a 1 cm path-length quartz cell containing phosphate buffered saline (PBS, pH ~ 7.0 - 7.4) as the reference. A UV/visible spectrpohotmeter, such as, Varian Cary 3E UV-Visible Spectrophotometer with a LabSphere DRA-CA-302 beam splitter or the like, can be used in this measurement. Percent transmission spectra are collected at a wavelength range of 250-800 nm with %T values collected at 0.5 nm intervals. This data is transposed onto an Excel spreadsheet and used to determine if the lenses conform to Class 1 UV absorbance. Transmittance is calculated using the following equations:

UVA %T = Average % Transmission between 315 nm and 380 nm x 100 UVB %T = Average % Transmission between 280 nm and 315 nm x 100 Violet %T = Average % Transmission between 380 nm and 440 nm x 100 Chemicals

The following abbreviations are used in the following examples: NVP represents N-vinylpyrrolidone; DMA represents N,N-dimethyl acrylamide; MMA represents methyl methacrylate; TEGDMA represent triethyleneglycol dimethacrylate; EGMA represents ethylene glycol methyl ether methacrylate; AMA represents allyl methacrylate; V64 represents 2,2'-dimethyl-2,2'azodipropiononitrile; V88 represents 1,T- Azobis(cyanocyclohexane) which has a 10-hour half-life temperature of 88°C; Nobloc is 2-[3-(2H-Benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate from Aldrich; RB247 is Reactive Blue 247; TAA represents tert-amyl alcohol; PrOH represents 1 -propanol; I PA represents isopropanol; PBS represents a phosphate-buffered saline which has a pH of 7.2±0.2 at 25°C and contains about 0.044 wt.% NaH ₂ P0 ₄ -H ₂ 0, about 0.388 wt.% Na ₂ HP0 ₄ -2H ₂ 0, and about 0.79 wt.% NaCI and; wt.% represents weight percent; D6 represents monobutyl-terminated monomethacryloxypropyl-terminated polydimethylsiloxane (M.W. 600 to 800 g/mol); “G1” macromer represents a di- methacryloyloxypropyl-terminated polysiloxane (Mn ~ 10.7K g/mol, OH content ~ 1.8 meq/g) of formula (A) shown above.

Example 2

A polydiorganosiloxane vinylic crosslinker having pendant reactive functional groups (e.g., primary amino groups) is prepared according to the procedures shown in Scheme 1

Scheme 1

Synthesis of the precursor

275.9 g of octamethylcyclotetrasiloxane(M.W. 296.62), 12.0 g of 1 , 3,5,7- tetramethylcyclotetrasiloxane (M.W. 240.51), 15.3 g of 1 ,3-bis(3- methacryloxypropyl) tetramethyldisiloxane (M.W. 386.63), and 0.9 g of trifluoromethanesulfonic acid (M.W. 150.08) are weighed into a 500 imL round bottom flask. After the reaction is run at 35°C for 24 h, 170 ml_ of 0.5% sodium hydrogen carbonate is added. The collected organic portion is further extracted five times with de-ionized water (170 ml_ per cycle). Anhydrous MgSO4 is added to the collected organic solution, followed by -350 ml_ of additional CHCl3, and the solution is then stirred overnight. After filtration, the solvent is removed via Rotovap, followed by high vacuum. 102 g of final product (the precursor) is obtained.

Hvdrosilylation Reaction with Allylamine

A small reactor is connected to a heater and air condenser with drying tube. 21 g of toluene, 15 g of above precursor, and 2.17 g of allylamine are added to the reactor. After the solution temperature is stabilized at 30 °C, 152 mI_ of Karstedt’s catalyst (2 Pt% in xylene) is added. After 2h, the conversion of Si-H of 100% based on IR is achieved. The solution is then transferred to a flask, concentrated using Rotovop, followed by precipitation in actenotrile/water mixture (75/25) three times. After removal of solvent via Rotovop, followed by high vacuum, 10 g of hazy liquid is obtained. The molecular weight is determined by H ¹ NMR spectroscopy

Example 3

A photochromic polydiorganosiloxane vinylic crosslinker is prepared according to the procedures shown in Scheme 2.

Scheme 2

4.87 g of polydiorganosiloxane vinylic crosslinker with pendant aminopropyl groups (1 eq amine), 2.33 g of 3, 3-bis(4-methoxyphenyl)-6, 11 -dimethyl-13-(2- hydroxycarbonylethyl)carboxyyethoxy-13-phenyl-3H,13H-indeno [2’,3’:3,4]naphtho[1,2- b]pyran (5 eq), 0.96g of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), 0.76 of N,N-dimethylaminopyridine (DMAP), 50 mL of dichloromethane (DCM) are added into a 500 mL round bottom flask.

Example 4 A photochromic polydiorganosiloxane vinylic crosslinker is prepared according to the procedures shown in Scheme 3.

Compound 4 can be prepared according to procedures described in U.S. Pat. No. 10081697.

All the publications, patents, and patent application publications, which have been cited herein above, are hereby incorporated by reference in their entireties.