This is a continuation-in-part of my copending application Serial No. 641,594-, filed August 17, 1984, now to be abandoned.

Field of the Invention This invention relates to optical contact lenses and materials therefor and, in particular, to alkylsilane polymers and alkylsilane polymer contact lenses.

Background of the Invention Many polymeric materials have been evaluated for potential utility as contact lens material, but a very limited number of materials have been found to form contact lenses which are satisfactory. Advances in contact lens materials and techniques have come in small steps, which have been excruciatingly slow and difficult. Polymers and methods which appeared attractive have fallen by the wayside. The problems are myriad and predictability is low. It is difficult and frequently impossible to predict optical quality, strength and flexibility, resistance to protein build-up, • machining and fabrication characteristics, dimensional stability, oxygen permeability, and general biological compatability. It is impossible to predict, or even to speculate as to possible optical, oxygen permeability, and biological characteristics of structural and industrial silanes such as disclosed by Campbell, U.S. Patent No. 2,958,681 for example. Reference is made to the literature, in texts, treatises and technical literature which describe silicon compounds, commonly referred to as silanes,

particularly alkylsilanes. While the present invention departs from this chemistry in important and substantial ways, this body of chemistry is fundamental to the present invention. Silane chemistry is quite well known and reported in the literature. An excellent treatment of the chemistry of silanes is given by Sommers, L.H.; Mitch, P.A; andGoldberg, G.M., "Synthesis and properties of Compounds with a Framework of Alternate Silicon and Carbon Atoms, J.A.C.S., 71, 2746, (1949). Surveys of this body of chemistry are found in KIRK-OTHMER, ENCYCLOPEDIA OP CHEMICAL TECHNOLOGY, 3rd Ed. at Vol. 20, pp 887-911. The chemistry of organosilicon compounds is described in ORGANOSILICON COMPOUNDS, Bazant, Chvalovsky and Rathovsky, Academic Press, Inc., New York, 1965.

The literature on contact lenses and contact lenses and contact lenses containing silicone compounds is massive, including hundreds of patents. This massive body of literature is not considered analogous to the present invention except as to the general techniques for forming optical contact lenses, e.g. cutting and polishing.

Silanes have been utilized in preparative organic chemistry and for a number of specialty applications, including waterproofing compounds for morter and fabrics and the like, as accellerators in some polymer operations, and as intermediates in the preparation of organosiloxanes.

While the chemistry, vis-a-vis reaction conditions, of alkyl silanes is known and reasonably well understood, it has not, to the inventor's knowledge, been proposed to use suchmaterials as the principal constituent polymer in contact lenses. In particular, the unique characteristics of such contact lenses has not been reported, insofar as is known to the inventor. Given the uncertainty as to lens characteristics of given polymer

systems, there was no reason to expect that such materials would be useful as lens polymers.

Summary of the Invention The present invention relates to a novel class of contact lenses comprising polymers resulting from the polymerization or copolyrnerization alkyl silanes, having the general structure:

wherein R through R . are hydrogen or alkyl , aryl , ^a J aralkyl , or silyl moieties, which may include vinyl, allyl, acrylyl , acrylic, methacrylic, ethacrylic, or pyrrolidinonyl substituents and may also contain up to about 35 weight percent siloxyl, and wherein either X. or X , or both X and X are vinyl polymerizable group containing moieties. The term "vinyl polymerizable group" is used here in a particular sense to mean a polymerizable group containing the carbon-carbon double bond which is polymerized in the formation of polyvinyl polymers, i.e. the following structures:

-C=C- and -C-C=C-; exemplary of which vinyl polymerizable groups are: vinyl, allyl, acrylyl, acrylyl, methacrylyl , or styryl.

Exemplary of the monomers suitable for forming the polymers and copolymers of this invention are the following:

wherein n is a positive integer from 1 to 5 , preferrably 1 to 3 ;

wherein n is a positive integer from 1 to 5, preferrably 1 to 3 ;

wherein n is a positive integer from 1 to 5, preferrably 1 to 3;

wherein n is a positive integer from 1 to 5, preferrably 1 to 3;

wherein n is a positive integer from 1 to 5, preferrably 1 to 3;

wherein n is a positive integer from 1 to 5, preferrably 1 to 3 and R-^, R ₂ and R3 are selected from the group consisting of methyl,

phenyl, , alkylmethoxy, phenylmethyl, and N-alkyl-pyrrol- idinonyl

wherein n is a positive integer from 1 to 5, preferrably 1 to 3;

wherein n is apositive integer from 1 to 5, preferably 1 to 3, and R4 and R5 are selected from the group consisting of methyl,

phenyl , , alkylmethoxy, phenylmethyl, and N-alkyl-pyrrol- idinonyl

wherein n is a positive integer from 1 to 5, preferably 1 to 3, and Rβ and R7 are selected from the group consisting of methyl,

phenyl, alkylmethoxy, phenylmethyl, and N-alkyl-pyrrol- idinonyl

R8 R9

Rio R11 wherein n is a positive integer from 1 to 5, preferably 1 to 3, and Rg - Rχι are selected from the group consisting of methyl,

phenyl, alkylmethoxy, phenylmethyl, and N-alkyl-pyrrol- idinonyl and

whereinn is apositive integer from 1 to 5, preferably

1 to 3, and R^ ₂ and R13 are selected from the group consisting of methyl,

phenyl, alkylmethoxy, phenylmethyl, and N-alkylpyrrol- idinonyl.

Silanes with two polymerizable groups and polymers thereof and lenses of such polymers are also contemplated within the scope of the invention. Exemplary of such monomers are:

wherein n is apositive integer from 1 to 5, preferably 1 to 3, and R14 and R15 are selected from the group consisting of methyl,

phenyl, alkylmethoxy, phenylmethyl, and N-alkyl-pyrrol- idinonyl

wherein n is a positive integer from 1 to 5, preferably

11 ttoo 33,, aanndd R _n 1- _c 6 _r ttoo R.ιy_ are selected from the group consisting of methyl ,

phenyl, ,

alkylmethoxy, phenylmethyl, and N-a]kylpyrrol-idinonyl A monomer which is predominantly silane is:

wherein n is a positive integer from 1 to 5, preferably 11 ttoo 33,, aanndd R to R are selected from the group consisting of

Other monomers which include two polymerizable groups include:

wherein n is a positive integer from 1 to 5, preferably 1 to 3, ;

whereinn is apositive integer from 1 to 5, preferably 1 to 3, ;

wherein R ₂ 4 and R ₂ 5 are selected from the group consisting of methyl,

phenyl, alkylmethoxy, phenylmethyl, and N-alkylpyrrol- idinonyl.

In general, vinyl, allyl, acrylallyl, acrylic, methacrylic or ethacrylic derivatives of the compounds referred to which include one or more polymerizable groups such as vinyl, allyl, acrylic, methacrylic or ethacrylic may be considered equivalent to the specific, exemplary monomers, and polymers and copolymers of the same may be used as contact lens materials and lenses. The alkylsilane polymer lenses of this invention have been discovered to have extremely beneficial, and most unexpected and unpredictableproperties as contact lenses. For example, the most comparable lenses, of siloxyl based polymers, have an oxygen permeability, Dk value (see, e.g. Fatt, I. and St. Helen, R., Oxygen Tension Unύ&X. n Oxygen-Permeable Contact Lens, American Journal of Optrometry, July 1971, pp.545-555, for a discussion of Dk values) in the 20's, the highest being about 30 to 32. The alkylsilane polymer lenses of this invention have a calculated Dk value of as high as 40 or morel The exremely high Dk value, as shown by wearer comfort, has been demonstrated for the contact lenses of this invention. In addition, these alkylsilane polymer lenses have an even greater resistance to protein contamination than the silicone polymer lenses. These alkylsilane polymer lenses are also harder and, very surprisingly, can be made wettable by inclusion of appropriate hydrophylic substituents much easier than comparable silicone polymer contact lensesI These very surprising advantages, coupled with good optical quality could not have been

predicted, or even guessed at in advance. These lens polymers can be formulated with a relatively high phenyl substituent content, giving lenses having a high index of refraction which can be made thinner and lighter than conventional contact lenses, and more easily fabricated into bifocal lenses than is possible with conventional and know lens polymers. Surface characteristics can be modified by inclusion of specific moieties in the polymer; for example, methoxy alkyl, ethoxy alkyl, or n- alkylpyrrolidinonemay be included to improvewettability. Monomers having two polymerizable groups may be used, thus resulting in a fully crosslinked lens polymer. It is even possible to prepare highly hydrated lenses from the polymers of this inventionI Description Ω£ Jtύie Preferred Embodiment

No new silane chemistry, per se, is involved in the present invention; rather, it has been discovered that alkylsilane polymer contact lenses have most unexpected and unpredicted advantages over other lenses and, more particularly, over the most comparable lenses, those formed of silicone polymers.

The alkylsilanes used in forming the polymers from which the lenses of the present invention are manufactured are most conveniently prepared by the action of a polymerizable vinyl group containing moiety, e.g. methacrylic acid, on a chloroalkyl or bromoalkyl substituted silane, such as chloromethyl trimethylsilane or di-chloromethyl dimethylsilane, in the presence of a base such as pyridine or triethyl amine. The higher homologues of the series are conveniently prepared by the action of the Grignard Reagent of a silane, such as trimethylsilylmethyl magnesium chloride on a chlorosilyl- alkyl methacrylate, e.g. trichlorosilyl propyl methacrylate, to give tris(trimethylsilylmethyl) silyl- propyl methacrylate.

Example A Trimethylsilyl Methyl Methacrylate

Trimethylsilylmethyl methacrylate was prepared as follows: Methacrylic acid (29.6 g) was dissolved in dry

5 ether (600 ml) , sodium carbonate (18.6 g) was added slowly to form the sodium salt. Chloromethyl trimethyl silane

(42.2 g) was added to the gelatenous solid formed from the preceeding salt forming reaction, followed by the addition of hydroquinone (1.00 g) . The mixture was refluxed for 72

10 hours, washed with water, dryed over magnesium sulfate, filtered and distilled giving a 21.7 g of product which boiled at 29.5°C. at 0.3 mm Hg, 37% of theoretical yield.

The product was washed with basic carbonate solution until the wash was free of color and then washed with distilled

■15 water to remove any hydroquinone which may have been carried over during distillation, and dried over magnesium sulfate and stored under refrigeration.

Example B Phenyldimethylsilyl Methyl Methacrylate 20 Phenyldimethylsilyl Methyl Methacrylate was prepared by reacting phenyl dimethyul chloromethyl silane (161 g) with methacrylic acid (132 g) and triethylamine (132 g) in benzene (300 ml), with hydroquinone (1.0 g) added to inhibit polymerization during the reaction. The mixture 25 was refluxed for 64 hours. The resulting product was washed, dried and distilled, and the boiling point of the product was found to be 86°C. at 0.1 mm Hg. The yield, 105.2 g, was 51.5% of theoretical. Theproduct was further washed and stored as in example I. 30 These procedures are, of course, well known reactions. Similar reactions and techniques are suitable for the preparation of the monomers of interest.

Lens Manufacture The following general technique was followed in the 35

preparation of lens blanks and lenses:

Monomers in the specified ratio and initiator were thoroughly mixed and dryed over magnesium sulfate and filtered. The dryed, filtered monomer mixture was placed in molds under nitrogen atmosphere and cured be slowly raising the temperature to about 100°C. for about 2 hours followed by a reduction to a post-cure temperature of about 80°C. for a post cure of about 15 hours. The resulting lens blank was examined and is then machined to form contact lenses according to conventional procedures for the manufacture of contact lenses.

The following examples of lenses formed by the technique described exemplify the invention.

Lens Material No. 1 Trimethylsilyl methyl methacrylate 45%*

Methyl methacrylate 41%

N-vinyl pyrrolidinone 3%

Methacrylic acid 6%

Ethylene glycol dimethacrylate 5% Initiator** (Trace)

* Percentages in all examples by weight. ** 2,2'azobis-2,4-dimethyl-4-methoxy- valeronitrile 0.001-0.5% in all Lens examples Initial Cure Temperature 102°C. Initial Cure Time 2 hours.

Post Cure Temperature 82-85°C.

Post Cure Time 16 hours.

Lens Qualities:

Clarity Excellent Hardness Good

Machinability Good ettability Good

Dimensional stability Excellent

Lens Material No. 2 Trimethylsilyl methyl methacrylate 30%*

Methyl methacrylate 56%

N-vinyl pyrrolidinone 3%

Methacrylic acid 5%

Ethylene glycol dimethacrylate 6%

Initiator** (Trace)

Initial Cure Temperature 76°C.

Initial Cure Time 3/4 hours.

Post Cure Temperature 52-58 ⁰ C.

Post Cure Time 18 hours.

Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stability Excellent

Lens Material No. 3

Trimethylsilyl methyl methacrylate 60%*

Methyl methacrylate 26%

N-vinyl pyrrolidinone 3%

Methacrylic acid 5%

Ethylene glycol dimethacrylate 6%

Initiator** (Trace)

Initial Cure Temperature 69°C.

Initial Cure Time 3/4 hours.

Post Cure Temperature 52-58 ^Q C.

Post Cure Time 18 hours.

Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stability Excellent

Lens Material No. 4

Trimethylsilyl methyl methacrylate 45%*

Methyl methacrylate 41%

N-vinyl pyrrolidinone 3%

Methacrylic acid 6%

Ethylene glycol dimethacrylate 5%

Initiator** (Trace)

Initial Cure Temperature 102 ^O C.

Initial Cure Time 2 hours.

Post Cure Temperature 82-85°C.

Post Cure Time 16 hours.

Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stability Excellent

Lens Material No. 5

Trimethylsilyl methyl methacrylate 30%*

Methyl methacrylate 56%

N-vinyl pyrrolidinone 3%

Methacrylic acid 5%

Ethylene glycol dimethacrylate 6%

Initiator** (Trace)

Initial Cure Temperature 76°C.

Initial Cure Time 3/4 hours.

Post Cure Temperature 52-58 ⁰ C.

Post Cure Time 18 hours.

Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stability Excellent

Lens Material No. 6

Trimethylsilyl methyl methacrylate 60%*

Methyl methacrylate 26%

N-vinyl pyrrolidinone 3%

Methacrylic acid 5% Ethylene glycol dimethacrylate 6% Initiator** (Trace)

Initial Cure Temperature 69°C. Initial Cure Time 3/4 hours. Post Cure Temperature 52-58 ⁰ C. Post Cure Time 18 hours. Lens Qualities: Clarity Excellent Hardness Good Machinability Good Wettability Good Dimensional stability Excellent

Lens Material No. 7 Trimethylsilyl methyl methacrylate 86%* N-vinyl pyrrolidinone 3% Methacrylic acid 5% Ethylene glycol dimethacrylate 5% Initiator** (Trace)

Initial Cure Temperature 57°C. Initial Cure Time 3/4 hours. Post Cure Temperature 57°C. Post Cure Time 21 hours. Lens Qualities: Clarity Excellent Hardness Good Machinability Good Wettability Good Dimensional stability Exceptional

Lens Material No. 8 Trimethylsilyl methyl methacrylate 40%* Methyl methacrylate 31% N-vinyl pyrrolidinone 3% l,3,Bis(methyacryloxy propyl) 1,1 ^» ;3,3'- tetrakis(trimethylsiloxy)disiloxane 20%

Methacrylic acid 6%

Initiator** (Trace)

Initial Cure Temperature 80°C.

Initial Cure Time 3/4 hours.

Post Cure Temperature 55-58°C.

Post Cure Time 21 hours.

Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stability Excellent

Lens Material No. 9

Trimethylsilyl methyl methacrylate 25%*

Methyl methacrylate 47%

N-vinyl pyrrolidinone 3%

Trimethoxysilyl propyl methacrylate 25%

Initiator** Trace

Initial Cure Temperature 58<>C.

Initial Cure Time 1 1/4 hours.

Post Cure Temperature 58°C

Post Cure Time 20 hours.

Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stability Excellent

Lens Material No. 10

Phenylmethylsilyl methylmethacrylate 50%*

Methyl methacrylate 36%

N-vinyl pyrrolidinone 3%

Methacrylic acid 6%

Ethylene glycol dimethacrylate 5%

Initiator** Trace

Initial Cure Temperature 58°C. Initial Cure Time 1 1/4 hours. Post Cure Temperature 58 ^θ C. Post Cure Time 20 hours. Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stability Excellent This lens material has an exceptionally high refractive index, making it ideally suited to the manufacture of bifocal and thin lenses. Phenyldimethylsilyl methylmethacrylate 60%* Methyl methacrylate 26% N-vinyl pyrrolidinone 3% Methacrylic acid 6% Ethylene glycol dimethacrylate 5% Initiator** Trace

Initial cure temperature 104° Initial cure time 2 hours Post Cure Temperature 83-85 ^C -C. Post Cure Time 16 hours. Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stability Excellent This lens material has an exceptionally high refractive index, making it ideally suited to the manufacture of bifocal and thin lenses.

Lens Material No. 12 Phenylmethylsilyl methylmethacrylate 86%* N-vinyl pyrrolidinone 3%

Methacrylic acid 6%

Ethylene glycol dimethacrylate 5%

Initiator** Trace

Initial Cure Temperature 104°C.

Initial Cure Time 2 hours.

Post Cure Temperature 84-86°C.

Post Cure Time 18 hours.

Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stab] Llity Excellent

This lens material has an exceptionally high refractive index, making it ideally suited to the manufacture of bifocal and thin lenses.

Lens Material No. 13 Trimethoxylsilyl propylmethacrylate 45%* Methyl methacrylate 41% N-vinyl pyrrolidinone 3% Methacrylic acid 5% Ethylene glycol dimethacrylate 5% Initiator** Trace

Initial Cure Temperature 102 ^O C. Initial Cure Time 2 hours. Post Cure Temperature 82-85°C. Post Cure Time 16 hours. Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stability Excellent

Lens Material No. 14 Trimethylsilyl methyl methacrylate 45%*

Hydroxyethyl methacrylate 10%

N-vinyl pyrrolidinone 50%

Methacrylic acid 4%

Ethylene glycol dimethacrylate 1%

Initiator** Trace

Initial Cure Temperature 57°C.

Initial Cure Time 2 hours.

Post Cure Temperature 57°C.

Post Cure Time 20 hours.

Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good ettability Good

Dimensional stability Excellent

On hydrating in 0.9% saline solution, this lens material reached an equilibrium hydration level of 42.7°, providing a clear, rigid hydrating lens material.

Lens Material No. 15 Phenyldimethylsilyl methylmethacrylate 20%* Hydroxyethyl methacrylate 74% Methacrylic acid 5%

Triethylene glycol dimethacrylate 5% Initiator** Trace

Initial Cure Temperature 102°C. Initial Cure Time 2 hours. Post Cure Temperature 84-86°C. Post Cure Time 18 hours. Lens Qualities:

Clarity Excellent

Hardness Good

Machinability Good

Wettability Good

Dimensional stability Excellent This lens material has an exceptionally high refractive

index, making it ideally suited to the manufacture of bifocal and thin lenses, and, additionally, reached an equalibrium of 18.5% hydration in 0.9% saline, thus providing a clear, rigid hydrating lens material.

Lens Material No. 16 Phenyltetramethyldisilylmethylene- methylmethacrylate 50%* Methyl methacrylate 38.5% Methacrylic acid 6% Ethylene glycol dimethacrylate 5% N-vinylpyrrolidinone 3% Initiator** Trace

Initial Cure Temperature 100°C. Initial Cure Time 2 hours. Post Cure Temperature 82-83°C. Post Cure Time 17 hours. Lens Qualities: Clarity Excellent Hardness Good Machinability Good Wettability Good Dimensional stability Excellent This lens material has an exceptionally high refractive index, making it ideally suited to the manufacture of bifocal and thin lenses.

Discussion and Equivalents These lens materials had excellent optical properties and some had outstanding refractive index characteristics. All were ideal for the manufacture of high quality exceptionally comfortable lenses. Some had moderate to high hydration capacity, in addition to being excellent, clear comfortable lens characteristics.

One of the important discoveries of this invention is that these lens materials are far more comfortable for thewearer than the most nearly comparable lenses formed of

siloxanyl polymers, the silicone polymers of the prior art and of my earlier filed copending patent applications. Wearer comfort is somewhat subjective but reflects real differences. Two objective observations are believed to explain the unexpectedly high comfort factor of the lenses of this invention. First, oxygen permeability is very high, thus contributing to healthier eye tissue and greater comfort. Second, these lens materials are exceptionally resistant to the buildup of proteins on the lens surfaces. A third, highly unexpected, factor believed to contribute to wearer comfort is the wettability of the lens materials of this invention. Silanes have typically been used in waterproofing applications and one would predict a highly hydrophobic lens material. Quite surprisingly, however, the lenses of this invention are quite hydrophylic and, indeed, in some formulations, hydrate to a moderate to high level.

Another surprising characteristic of lens materials of the present invention is that it is possible to form excellent lens materials with excellent optical, refractive, mechanical and comfort properties without the presence of methyl methacrylate, or with only very minor amounts of methyl methacrylate

It will be readily understood by those skilled in the art that the foregoing lens material formulations are only exemplary of avast number of lens materials and lenses which can be manufactured within the scope of this invention. Many analogous and homologous monomers of the silane family may be substitued for those shown in the examples. Initiators may be selected from among the many which are suitable for intiating the polymerization of vinyl group containing monomers.

In general, the alkyl silanes of this invention comprise greater than 5% and preferrably greater than 20% of the polymeric lenses and lens materials and my comprise

up to about 95%, preferrably up to about 90%, of such materials and lenses. In the preferred embodiment, the lens material is formed from the polymerization of alkyl silanes with a cross-linking monomer and a monomer, such as n-vinylpyrrolidinone or hydroxyethyl methacrylate, or both, which contributes to the wettability or hydration of the lens, or to both wettability and hydration of lenses. This hydrophylic constituent may comprise, preferrably, at least 2 to 3% and may comprise up to about 75% or more of the polymeric lens material.

Exemplary percentages of selected formulations are shown in the following tables:

I Trimethylsilyl methyl methacrylate 5 to 95 weight % Methyl methacrylate 1 to 50 wieght %

N-vinyl pyrrolidinone 1 to 50 wieght %

Methacrylic acid 1 to 10 weight %

Ethylene glycol dimethacrylate 1 to 10 weight %

II Trimethylsilyl methyl methacrylate 20 to 90 weight % Methyl methacrylate 20 to 60 weight %

N-vinyl pyrrolidinone 1 to 10 weight %

III Trimethylsilyl methyl methacrylate 20 to 90 weight % N-vinyl pyrrolidinone 3 to 60 weight %

Methacrylic acid 1 to 10 weight %

IV Trimethylsilyl methyl methacrylate 20 to 95 weight % N-vinyl pyrrolidinone 5 to 80 weight % V

Trimethylsilyl methyl methacrylate 25 to 95 weight % Hydroxyethyl methacrylate 5 to 75 weitht %

VI Trimethylsilyl methyl methacrylate 5 to 95 weight % Methyl methacrylate 5 to 90 weight %

l,3,Bis(methyacryloxy propyl) 1,1' ;3,3 ^• - tetrakis(trimethylsiloxy)disiloxane 5 to 35 weight %

VII Phenylmethylsilyl methylmethacrylate 5 to 95 weight % Methyl methacrylate 5 to 50 weight %

VIII Phenylmethylsilyl methylmethacrylate 5 to 95 weight % Methacrylic acid 5 to 50 weight %

IX Trimethoxylsilyl propylmethacrylate 5 to 95 weight % Methyl methacrylate 5 to 60 weight %

X Trimethyoxysylyl propylmethacrylate 5 to 95 weight% Hydroxyethyl methacrylate 5 to 50 weight% XI

Phenyldimethylsilyl methylmethacrylate 10 to 95 weight % Hydroxyethyl methylmethacrylate 5 to 90 weight %

XII Phenyltetramethyldisilylmethylene- methylmethacrylate 5 to 95 weight % Methacrylic acid 5 to 60 weight %

Typically, in the preferred embodiments, a hydrophylic monomer would also comprise thepolymerization mix. . . It has also been found advantageous to include methacrylic acid and/or methyl methacrylate as a monomer in the formation of the polymerized lense material; however, one of the surprising discoveries of this invention is that high quality lenses can be formed without either of these constituents.

Polymeric materials resulting from the polymerization or copolymerization alkyl silanes, having the following general structures and lenses formed therefrom are within the contemplation and concept of this invention:

wherein R through R . are hydrogen or alkyl , aryl , ^a J aralkyl , or silyl moieties, which may include vinyl, allyl, acrylyl, acrylic, methacrylic, ethacrylic, or pyrrolidinonyl substituents and may also contain up to about 35 weight percent siloxyl, and wherein either X- or X„, or both X and X are vinyl polymerizable group containing moieties. The term "vinyl polymerizable group" is used here in a particular sense to mean a polymerizable group containing the carbon-carbon double bond which is polymerized in the formation of polyvinyl polymers, i.e. the following structures:

-C=C- and -C-C=C-; exemplary of which vinyl polymerizable groups are: vinyl, allyl, acrylyl, acrylyl, methacrylyl , or styryl .

Exemplary of the monomers suitable for forming the polymers and copolymers of this invention are the following:

wherein n is a positive integer from 1 to 5, preferably 1 to 3;

wherein n is a positive integer from 1 to 5, preferrably 1 to 3;

wherein n is a positive integer from 1 to 5, preferrably 1 to 3;

wherein n is a positive integer from 1 to 5, preferrably 1 to 3;

30

35

CH ₃

wherein h is a positive integer from 1 to 5, preferrably 1 to 3;

wherein n is a positive integer from 1 to 5, preferrably 1 to 3 and R _f R and R3 are selected from the group consisting of methyl,

phenyl, , alkylmethoxy, phenylmethyl, and N-alkyl-pyrrol- idinonyl

wherein n is a positive integer from 1 to 5, preferrably 1 to 3;

wherein n is a positive integer from 1 to 5, preferably

1 to 3, and R4 and R5 are selected from the group consisting of methyl,

phenyl, alkylmethoxy, phenylmethyl, and N-alkyl-pyrrol- idinonyl

wherein n is a positive integer from 1 to 5, preferably 1 to 3, and Rg and R7 are selected from the group consisting of methyl.

phenyl, alkylmethoxy, phenylmethyl, and N-alkyl-pyrrol- idinonyl

wherein n is a positive integer from 1 to 5, preferably

1 to 3, and Rg - Rχι are selected from the group consisting of methyl,

phenyl, alkylmethoxy, phenylmethyl, and N-alkyl-pyrrol- idinonyl and

wherein n is a positive integer from 1 to 5, preferably

1 to 3 , and Rι ₂ and R ₁ 3 are selected from the group consisting of methyl,

phenyl, alkylmethoxy, phenylmethyl, and N-alkylpyrrol- idinonyl.

Silanes with two polymerizable groups and polymers thereof and lenses of such polymers are also contemplated within the scope of the invention. Exemplary of such monomers are:

wherein n is a positive integer from 1 to 5, preferably 1 to 3, and R14 and R15 are selected from the group consisting of methyl,

phenyl, alkylmethoxy, phenylmethyl, and N-alkyl-pyrrol- idinonyl

wherein n is a positive integer from 1 to 5, preferably

1 to 3, and R _{η c} to R _n _ are selected from the group o ιy consisting of methyl,

phenyl , ,

alkylmethoxy, phenylmethyl, and N-alkylpyrrol-idinonyl . A monomor which is predominantly silane is:

wherein n is a positive integer from 1 to 5, preferably 1 1 ttoo 33,, aanndd R„ ₀ to R are selected from the group consisting of:

Other monomers which include two polymerizable groups include:

;

wherein n is a positive integer from 1 to 5, preferably 1 to 3;

whereinn is apositive integer from 1 to 5, preferably 1 to 3,;

wherein R 4 and R ₂ 5 are selected from the group consisting of methyl,

phenyl, alkylmethoxy, phenylmethyl, and N-alkylpyrrol- idinonyl.

In general, vinyl, allyl, acrylallyl, acrylic, methacrylic or ethacrylic derivatives of the compounds referred to which include one or more polymerizable groups such as vinyl, allyl, acrylic, methacrylic or ethacrylic may be considered equivalent to the specific, exemplary monomers, and polymers and copolymers of the same may be used as contact lens materials and lenses.

Industrial Application This invention is useful in the optical industry and, particularly, in the manufacture of optical contact lenses for the correction of certain human visual defects.