BACKGROUND OF THE ART Variable transmission electrooptic devices, including, but not limited to, laminated electrochromic and liquid crystal devices, are described in the art. For example, it is known that the optical properties of electrochromic materials change in response to electrically driven changes in oxidation state. When an applied voltage from an external power supply causes electrons to flow to (reduction) or from (oxidation) an electrochromic material, its transmittance properties change. Liquid crystal devices can also be used to regulate light transmission or other optical properties in response to applied voltage. In the manufacture of various laminated electrooptic devices, particularly electrochromic devices, peripheral edge seals are necessary.

A typical laminated electrochromic device, such as an electrochromic lens, comprises a first electroconductive material layer, which layer serves as a first electrode, an electrochromic layer, an ion-conducting material layer and a second electroconductive layer which serves as a second electrode. Preferably, a complementary electrochromic layer is also used. These electroconductive and electrochromic layers, along with the ion-conducting material layer, can be

arranged as a single stack deposited on a first substrate or lens which is then laminated to a second substrate or lens, or they can be arranged such that the electrodes are coated on separate substrates or lenses, followed by placement on the substrates or lenses of one or more electrochromic layers.

The coated substrates or lenses are then laminated via a technique which positions an ion-conducting material between the coated lenses. Preferably, an ion-conducting polymer, which also serves as a bonding agent, is used to bond the complementary lenses.

As voltage is applied across the electrodes, ions are conducted through the ion-conducting material. When the electrode adjacent to the electrochromic film is the cathode, application of an electric field causes darkening of a cathodically-coloring film. Reversing the polarity causes electrochromic switching, and the film reverts to its high- transmittance state. Typically, an electrochromic film such as tungsten oxide is deposited on a substrate coated with an electroconductive film such as tin oxide or indium tin oxide to form one electrode. The counter electrode is typically a similar tin oxide or indium tin oxide coated substrate. To ensure reliable operation, the peripheral edge surface of the ion-conducting material layer generally must be sealed so as to maintain its water content within a range sufficient to provide required ion conductivity. Absent an adequate seal, moisture loss or gain through the exposed edge of the ion- conducting material layer impacts performance.

The peripheral edge surface of a laminated electrooptic device may be shaped to support or interlock with an edge seal. See, for example, commonly owned U. S. Pat. No.

5, 953, 150, which discloses a nubbed-edge design that facilitates application of an edge seal to the peripheral edge

surface of an electrooptic device. Commonly owned U. S. Pat.

No. 5, 969, 847 also discloses a method for sealing an electrooptic device, as do copending and commonly owned U. S.

Pat. Application Nos. 09/046, 386 and 09/190, 710, filed on March 23, 1998, and November 15, 1998, respectively. Copending and commonly assigned U. S. Pat. Application No. 09/211, 786, filed December 15, 1998, discloses improved epoxy edge seals for electrooptic devices.

U. S. Pat. No. 5, 327, 281 to Cogan discloses the use of epoxy to seal a cavity formed when a spacer is used to separate electrodes and contain a liquid electrolyte injected between the spaced electrodes. EP 0 855 615 A2 discloses an electrochromic device wherein the periphery of the substrates forming the device, other than where an injection port is located, is sealed with a sealant.

Liebowitz, in"Formulation of an Epoxy Compound for Maximum Moisture Resistance", Chapter 11 of"Epoxy Resins", discloses the use of fillers such as mica to improve the moisture resistance of various epoxies. U. S. Pat. No.

5, 657, 150 to Kallman et al., discloses an electrochromic device having a barrier layer which electrically isolates the device electrodes. PCT/US97/15842 discloses gas barrier coating compositions containing platelet-type fillers.

SUMMARY OF THE INVENTION The instant invention is directed to the use of improved sealant compositions containing platelet-type fillers to seal the peripheral edge surfaces of electrooptic devices.

More particularly, a sealant composition, preferably an epoxy sealant composition, containing an effective amount of a platelet-type filler, is applied as a moisture seal to the peripheral edge surface of a laminated electrooptic device,

such as a liquid crystal or electrochromic lens, display, window, sunroof or mirror, having a peripheral edge surface prone to moisture gain or loss. The instant sealant compositions are especially useful when moisture loss or gain through the peripheral edge surface of an electrooptic device is critical to device performance.

In another embodiment, the instant invention is directed to an electrooptic device, preferably an electrochromic device, having a peripheral edge seal containing an effective amount of a platelet-type filler. In the case of a laminated electrochromic device containing an ion-conducting polymer (ICP) interlayer, the improved seal of the instant invention preferably contacts the exposed outer edge of the ICP layer, which enables the water content of the ICP layer to be maintained within a suitable range. This in turn helps to maintain ion-mobility and device operability.

DETAILED DESCRIPTION OF THE INVENTION Other than in the Examples, or where otherwise indicated, all numbers quantifying ingredients, dimensions, ratios, ranges, reaction conditions, etc., used herein are to be understood as modified in all instances by the term "about".

The instant invention is directed to a method for sealing the peripheral edge surface of a laminated electrooptic device, said method comprising : a) applying an effective amount of a sealant composition to said peripheral edge surface, wherein said sealant composition contains an effective amount of a platelet-type filler ; and b) allowing said sealant composition to cure, if necessary.

The instant invention is further directed to a method for sealing all or a portion of the peripheral edge

surface of a laminated electrochromic device, said peripheral edge surface comprising the outer peripheral surfaces of first and second mated substrates, preferably first and second lenses, and the outer peripheral surface of a layer to be sealed, such as a bonding layer, preferably an ion-conducting polymer (ICP) layer, wherein the outer peripheral surface of said layer to be sealed is situated between the outer peripheral surfaces of said first and second substrates. This method comprises applying an effective amount of a sealant composition containing an effective amount of a platelet-type filler to the peripheral edge surface to be sealed.

In another embodiment, the instant invention is directed to a laminated electrooptic device which, absent an edge seal, is sensitive to moisture gain or loss through its peripheral edge. Such a device typically has a material capable of absorbing or desorbing water, such as an ion- conducting polymer, disposed between a first substrate and a second substrate, and contains a peripheral edge seal having a platelet-type filler incorporated therein. Preferably this seal is an epoxy seal which is in contact with the outer peripheral surface of the material sensitive to moisture gain or loss.

The instant invention is also directed to a laminated electrochromic lens comprising a first coated lens, a second lens which may or may not be coated and an ion- conducting polymer (ICP) layer which is disposed between said first and second lenses, said laminated electrochromic lens having a peripheral edge region prone to moisture gain or loss through the outer surface of said ion-conducting polymer layer, wherein said peripheral edge region contains a seal prepared from an admixture of a sealant and an effective amount of a platelet-type filler.

As used herein, the terms"sealant"and"sealant composition"refer to any type of sealant or sealant composition that can be applied to the peripheral edge surface of an electrooptic device and that is compatible with one or more platelet-type fillers. Suitable sealants include, but are not limited to, epoxies, acrylates, silicons, urethanes, and melamines. To prepare the improved edge seals of the instant invention, a suitable sealant is combined with a platelet-type filler via a conventional mixing technique, and an effective amount of the resulting admixture is applied to the peripheral edge surface to be sealed via a suitable application means. In the case of an electrochromic lens containing an ion-conducting polymer, the sealant/filler admixture is preferably applied over and contacts the ICP layer on the peripheral edge surface of the lens, thereby impeding moisture ingress/egress to/from the ICP layer.

Epoxies are preferred sealants due to their cure and adhesion properties. To prepare an epoxy-based edge seal of the instant invention, a conventional epoxy resin is combined with a curing agent and a platelet-type filler via a conventional mixing technique. In particular, preferred edge seals are prepared by : a) combining an epoxy resin, a suitable curing agent and an effective amount of a platelet- type filler to form a sealant admixture ; and b) applying an effective amount of said admixture to the surface to be sealed.

Suitable epoxy resins include, but are not limited to, bisphenol A-based resins, halogenated bisphenol A-based resins, phenol and cresol epoxy novalac resins, glycidyl ethers of phenol-aldehyde adducts, glycidyl ethers of phenol- hydrocarbon novalacs, heterocyclic glycidyl imides and amides, cycloaliphatic epoxy resins and aromatic and heterocylic glycidyl amine resins.

More preferred resins are aromatic glycidyl amine resins represented by formula (I) :

where : R2 is phenylene or naphthylene ; X is N, NR3, CH2N, CH2NR3, O or C (O)-O ; R3 is an alkyl group containing 1-4 carbon atoms, a cyanoethyl group or a cyanopropyl group ; n is 1 or 2 ; and m is 2 to 4.

Reaction of an epoxy resin with a suitable curing agent leads to formation of a crosslinked or thermoset epoxy sealant. Any suitable curing agent can be used. As used herein, the term"curing agent"refers to a compound which effects conversion of an epoxy resin to an epoxide polymer, which in turn is used to seal the peripheral edge surface of an electrooptic device. For example, Manich-base curing agents such as aliphatic polyamines can be used. Examples of suitable aliphatic polyamines include, but are not limited to, diethylene triamine and tetraethylene triamine, which are low viscosity liquids that are known to react with various epoxy resins at ambient temperatures. Aliphatic diamines based on propylene oxide and ammonia can also be used. For aromatic glycidyl amine resins, preferred curing agents are modified aliphatic amines such as Ancamine@ 1856, which is commercially available from Air Products and Chemicals, Inc.

An effective amount of a suitable curing agent is used. Relative to curing agents, the term"effective amount" refers to that quantity of curing agent necessary to form a cured epoxy seal within a reasonable time (e. g., less than about two (2) hours), at a temperature less than about 50° C, when combined with a given epoxy resin. In practice, suitable curing agent : epoxy resin weight ratios can be determined stoichometrically by skilled practitioners, or by following manufacturers'instructions. For example, if a polyamine curing agent is used, the approximate amount of amine curing agent needed to react completely with a given epoxy resin having a predetermined epoxy equivalent mass can be calculated by dividing the molecular mass of the amine by the number of reactive hydrogens. Adjustments may be necessary due to steric and diffusional effects.

If an epoxy sealant is used, a curing agent and an epoxy resin, alone or in combination with other constituents, can be combined via any conventional technique. For example, the resin and curing agent can be held in separate containers which exit into a common conduit or chamber, wherein mixing occurs. Alternatively, the resin and curing agent can be applied separately to a substrate or container, and mixed in situ. Resin/curing agent admixtures can also contain effective amounts of other constituents, including, for example, fillers, solvents, diluents, plasticizers, accelerators, curatives, and tougheners. Addition of such agents is well within the purview of skilled practitioners.

An effective amount of a platelet-type filler is added to the sealant composition prior to application of the sealant composition to an electrooptic device. Relative to fillers, the term"effective amount"refers to an amount of filler which can be dispersed in a given sealant and which

provides improved moisture barrier properties. Preferably, at least about 0. 1%, by weight, based on the total weight of the sealant is added. More preferably, at least about 1% by weight is added, up to the weight percent that can be dispersed into a given sealed composition. Weight percents ranging from about 5 to about 30 percentage are generally suitable.

Any platelet-type filler which is compatible with the sealant being used and which impedes moisture transport through the sealant is suitable. Preferred fillers are pigments having high aspect ratios, i. e., aspect ratios greater than about 20, preferably ranging from about 50 to about 100, which decrease the moisture permeability of a given sealing material. Examples of suitable fillers include : micas, vermiculite, clays, talcs, micaeous iron oxide, silicas, flaked metals, graphite flakes, glass flakes, phthalocyanine flakes, and the like. The preferred fillers for the purposes of this invention are micas.

Micas which can be used when practicing the instant invention include natural micas and synthetic micas. Examples of natural micas include: muscovite KAl2Si3O10 (OH)2 H2O, phlogopite (K2 (Mg, Fe2+)6 (Al2Si6O20) (OH,F)4), and biotite (K2 (MgFe2+) 6 (Al2Si6O20) Examples of synthetic micas include : fluorophlogopite (K2Mg6A12Si602oF4) and barium disilicic (Ba2Mg6Al2Si6020F4). Wet and dry ground micas are suitable. Of these micas, the preferred is muscovite mica.

Wet and dry ground muscovite mica, C. A. S. No. 12001-26-2, is commercially available from Franklin Industrial Minerals.

Surface-modified micas, including micas treated with one or more silane coupling agents, are more preferred.

Examples of such products are admixtures of a mica and an

epoxy silane. When the silane is absorbed onto the mica, it reacts with surface moisture to produce an alcohol and a silane polymer. Subsequent processing removes the volatile alcohol from the silane-coated mica surface. A preferred modified mica is muscovite mica treated with 3-glycidoxy propylene methoxysilane. This product is commercially available from Franklin Industrial Minerals as L-140-SM-E.

The resin/curing agent/filler or sealant/filler admixtures described herein can be applied to a laminated electrooptic device via any suitable application technique, including, for example, by dipping, brushing, swabbing or extrusion techniques or by the molding technique of co-pending and commonly assigned U. S. Patent Application Serial No.

09/046, 385, which is incorporated herein by reference. Also, the edge seal application techniques of co-pending and commonly assigned U. S. patent application Serial Nos.

09/046, 386 and 09/190, 710 and of U. S. Pat. No. 5, 969, 847, which are also incorporated herein by reference, can be used.

An effective amount of a sealing composition is applied, i. e., an amount sufficient to provide a seal of desired thickness over the desired portion of a given peripheral edge surface.

The electrooptic devices contemplated by this invention include, but are not limited to, eyewear, window, sunroof, skylight, display and mirror devices which have utility in various optical, automotive, architectural and aircraft applications. Preferred devices are electrochromic devices which contain an ion-conducting material layer disposed between mated first and second substrates. Various ion-conducting materials can be used, including for example, materials comprising hydrogen uranyl phosphate or polyethylene oxide/LiCl04. Also, ion-conducting polymer electrolytes or inorganic films such as LiNbO3, LiBo3, LiTaO3, LiF, Taô5,

NazAlF6, Sb205 nH2O + Sbz03, Na2O llAl20,, MgF2, ZrOz, Nb20s and Al203 can be used as the ion-conducting material. Preferred ion-conducting materials are ion-conducting polymers ; these polymers generally serve the dual functions of being ion- conducting electrolytes and mechanical adhesives. One class of suitable ion-conducting materials includes ion-containing polymers known as ionomers. These macromolecules contain ionizable groups covalently linked to a polymer chain, typically a hydrocarbon. Polystyrene sulfonic acid and poly (2-acrylamido-2-methyl-1-propanesulfonic acid) are examples of ionomers, both incorporating the protonic acid SO, H group on the polymer chain. Ionomers are generally formed by polymerizing monomers bearing both an ionizable group and an ethylenic, e. g. vinylic, group.

In accordance with a preferred embodiment of the present invention, the ion-conducting polymer electrolyte is a proton-conducting polymer selected from the group consisting of homopolymers of 2-acrylamido-2-methylpropanesulfonic acid (AMPSA) and copolymers of AMPSA with various monomers. Such polymers may be utilized in the form of preformed sheets which are laminated between the substrates, or in the form of liquid reaction mixtures of monomers which are cast and cured in place between the substrates. A preferred proton-conducting polymer electrolyte in accordance with the present invention is a copolymer of AMPSA and N, N-dimethylacrylamide (DMA), preferably cast and cured in place. More preferred copolymers of AMPSA and DMA are prepared from AMPSA and DMA monomers in a molar ratio range of about 1 : 3 to 1 : 2. The thickness of the polymer electrolyte is not believed to be critical but in general is in the range of 0. 001 to 0. 025 inch (0. 0254 to 0. 625 millimeter).

The first and second substrates of the instant laminated electrochromic devices are generally glass and/or organic polymeric substrates conventionally used to prepare electrochromic articles or devices. Preferably, polymeric organic substrates are used. Substrates to which the platelet-type filler-containing sealants of the present invention can be applied are preferably prepared from transparent materials suitable for producing eyewear lenses, such as lenses prepared from synthetic organic optical resins.

Alternatively, non-transparent substrates can be used.

Suitable transparent lenses may have a conventional refractive index (1. 48-1. 5), a relatively high refractive index (1. 60-1. 75), or a mid-range refractive index (1. 51- 1. 59), depending on the end use. In general terms, a transparent lens may have a refractive index within the range of between 1. 40 and 1. 80.

Synthetic polymer substrates that may be used as a lens material include, but are not limited to : thermoplastic polycarbonates, such as the carbonate-linked resin derived from bisphenol A and phosgene, which is sold under the trademark LEXAN@ ; polyesters, such as the material sold under the trademark, MYLAR@ ; poly (methylmethacrylates), such as the material sold under the trademark, PLEXIGLAS@ ; and polymerizates of a polyol (allyl carbonate) monomer, especially diethylene glycol bis (allyl carbonate), which is sold under the trademark Cor-390. Copolymers of the aforedescribed monomers/resins may also be used as a lens material. These and other transparent and non-transparent polymeric substrates known in the art for use for various optical and non-optical applications may be used.

Conventionally, in the preparation of electrochromic lenses, a cathodically coloring electrochromic material, usually tungsten oxide or compounds thereof, is deposited at a thickness of about 800 to 5, 000 Angstroms on a transparent substrate that has been previously coated with an electroconductive metal oxide film, such as tin oxide or indium tin oxide (ITO), which electroconductive film serves as one electrode. Preferably, the electroconductive film comprises indium and tin at a weight ratio of about 90 : 10.

The film thickness is preferably in the range of 800 to 4, 000 Angstroms for acceptable conductivity. The electroconductive and electrochromic films may be deposited by a variety of methods so long as the substrate is not deleteriously affected. The adhesion of an electroconductive metal oxide film directly to a plastic substrate may be improved by application of a primer to said substrate prior to coating.

See, for example, U. S. Patent No. 5, 471, 338 to Yu, Backfisch and Rukavina.

In such lenses, the counter electrode can be prepared by depositing a similar metal oxide coating on a second transparent substrate, with or without a complementary electrochromic film. A suitable complementary electrochromic film is a nitrogen-containing iridium oxide film as disclosed in U. S. Patent No. 5, 618, 390, to Yu, Backfisch et al. The ion-conducting material is then disposed between substrates so coated ; in the case of ion-conductive polymers, a precursor composition is generally cured or polymerized in situ by energy which passes through a substrate coated with an electroconductive film and/or an electrochromic film.

Lamination of electrochromic lenses can be accomplished by placing a curable ion-conducting polymer composition, i. e. a monomer solution containing one or more

monomers, an effective amount of an initiator and optionally one or more non-reactive diluents and/or additives, on the concave interface surface of a matched lens pair and moving the concave interface surface and the convex interface surface of the corresponding lens toward each other, thereby spreading the curable adhesive composition between the lenses. The curable ICP composition is then cured via exposure to a suitable energy source. Curing of the polymer places an ion- conducting polymer between the lenses while bonding the lenses into a laminate, thereby facilitating necessary ion flow.

After lamination, the laminated electrochromic device, preferably an electrochromic eyewear lens, comprises an ion-conducting material, preferably an ion-conducting polymer, sandwiched between suitably coated substrates.

Absent an edge seal, the ion-conducting material is exposed to the environment along the edge of the laminate. To reduce moisture transfer into or out of this layer, the edge of the lens must be sealed, preferably by applying an epoxy which contains a platelet-type filler such as mica to the edge.

These sealing compositions are exceptional moisture barriers and generally have acceptable adherence characteristics.

The cross-sectional profile of the instant edge seals generally conforms to the shape of the depression, groove or nub present on the device edge being sealed. The profile of the device edge is not believed to be critical.

Nubbed edges are preferred because they are easily formed using a beveled edger on one or each of the substrates forming a matched laminated pair. In the case of electrochromic lenses, the profile of the seal should not interfere with attachment of the lenses to a suitable frame.

EXAMPLES The following examples are presented for illustrative purposes only and are not intended to limit the invention in any way. In the examples : Tetrad@ X is N, N, N', N'-tetraglyglycidyl-m-xylenediamine, commercially available from Mitsubishi Gas Chemical Company.

EPONO 880, 8132 and 828 are bisphenol A-based (DGEBA) epoxy resins, commercially available from Shell Chemical Company.

Ancamide0 2353 is a modified polyamide curing agent (typical viscosity : 3000 cps @ 77° F), commercially available from Air Products and Chemicals, Inc.

Ancamine@ 2205 is an accelerated aliphatic amine curing agent (typical viscosity : 3600 cps @ 77° F), commercially available from Air Products and Chemicals, Inc.

Ancamine 1895 is a cycloaliphatic amine adduct curing agent (typical viscosity : 1200 cps @ 71° F), commercially available from Air Products and Chemicals, Inc.

Ancamine 1856 is a modified aliphatic amine curing agent (typical viscosity 3000 cps @ 77° F), commercially available from Air Products and Chemicals, Inc.

Ancamine 2432 is a modified aliphatic amine curing agent (typical viscosity : 300 cps @ 77° F), commercially available from Air Products and Chemicals, Inc.

Epicure@ 3235 is an epoxy curing agent, commercially available from Shell Chemical Company.

HiSILO T 700 and 303 are silicas, commercially available from PPG Industries, Inc.

TETA is a triethylenetetramine (curing agent), commercially available from Aldrich Chemical Company.

Mica is muscovite mica, commercially available from Franklin Industrial Minerals, unless otherwise indicated.

L-140-SM-E is surface modified mica, commercially available from Franklin Industrial Minerals.

EXAMPLE 1 MICA DISPERSION INTO AN EPOXY A mica-containing epoxy sealant composition suitable for use as an electrooptic device edge seal was prepared as follows : Part A-Resin Preparation 258 grams of Tetrad X was added to a 1. 0 liter Pyrex@ reaction kettle having a top containing a vacuum stirrer bearing, vacuum thermometer holder and vacuum takeoff joint. 57 grams of surface modified mica L-140-SM-E was added to a disposable container. The reaction kettle, without its top, was placed in a heating mantle and a Varias potentiometer was set to maintain Part A below 35° C. A mixing blade was then inserted into the Tetrad X, and mixing at approximately 190 rpm commenced. The surface modified mica was slowly added with a scoop. After all of the surface modified mica was added, mixing continued for 15 minutes. The top of the reaction kettle was then assembled (mixing blade inserted through vacuum sealing bearing, thermometer with vacuum seal inserted) and clamped into place. A dry ice trap was prepared using dry ice and acetone. Vacuum was applied, and Part A was mixed again at 600 rpm. Degassing continued for 2 hours, with care taken to not pull off gasses too quickly, thereby avoiding foaming. After degassing, a surface modified mica-containing resin was available for use.

Part B-Curing Agent Preparation The sequence described above was then repeated to prepare a mica-containing curing agent, using 277. 5 grams of Ancamine 1856 in a second 1 liter Pyrex reaction kettle. 55. 5 grams of L-140-SM-E was dispersed into the curing agent.

Additionally, 5. 5 grams of mercaptoacetic acid catalyst was added to the curing agent composition prior to the 600 rpm mixing step. After degassing, a mica/catalyst-containing curing agent was available for use.

Parts A and B can be mixed via conventional techniques and applied to a device edge via conventional application techniques.

EXAMPLES 2-13 WATER TRANSPORT INTO EPOXY-COATED CR-39 SHEETS, WITH AND WITHOUT MICA Flat sheets prepared from CR-39@ monomer, each approximately 5 cms wide X 5 cms long X 0. 6 cm thick, were dried at 50° C for one (1) week and then coated on all sides using the epoxy admixtures specified in Table I by mixing the resins and curing agents shown in accordance with manufacturer's instructions, swabbing the resulting admixtures onto the flats and allowing the admixtures to cure. This procedure was repeated twice for each flat to insure complete coverage. In Examples 8-12, 20 weight % mica was dispersed into the resin/curing agent admixture.

The initial water content of each flat was then determined via a near infrared (NIR) technique using a Braker IFS 66/S analyzer. Water content values were determined based on both 5250 cm-1 band areas and 5250/5800 band ratios. The epoxy sealed flats were next placed into a QUV accelerated weather tester for three (3) days at 50° C and 98% relative humidity. Final water contents were then determined using the above desired NIR technique. Results showing the impact of various seals on water ingress to the flats appear in Table I.

TABLE 1<BR> Resin: Curing Agent Weight Ratio (Active Basis) = 5:3.3* Using 5250 cm-1 Using 5250/5800 Band Ratio Example 20 Wt. Dry Wet % Moisture % Moisture No. Resin Curing Agent % Mica+ IR IR # IR Decrease Dry IR Wet IR # IR Decrease 2 --- --- --- 15.03 60.96 45.93 --- .0828 .3480 .2652 --- Control 3 TETRAD X ANCAMIDE 2353 N 15.97 74.80 58.83 -28.09 .0718 .3430 .2712 -2.26 4 TETRAD X ANCAMIDE 2205 N 14.84 76.13 61.29 -33.44 .0661 .03539 .2878 -8.52 5 TETRAD X ANCAMIDE 1895 N 14.11 56.65 42.54 7.38 .0730 .2970 .2240 15.54 6 TETRAD X ANCAMIDE 1856 N 12.36 26.46 14.1 69.30 .0621 .1329 .0708 73.30 7 TETRAD X ANCAMIDE 2432 N 13.34 53.49 40.15 12.58 .0709 .2913 .2204 16.89 8 --- --- --- 11.26 56.55 45.29 --- .0638 .3367 .2729 --- Control 9 TETRAD X ANCAMINE 2353 Y 11.24 63.68 52.44 -15.79 .0590 .3516 .2926 -7.23 10 TETRAD X ANCAMINE 2205 Y 10.59 65.40 54.81 -21.02 .0551 .3616 .3065 -12.31 11 TETRAD X ANCAMINE 1895 Y 11.25 35.20 23.95 47.12 .0590 .1892 .1302 52.29 12 TETRAD X ANCAMINE 1856 Y 9.90 17.29 7.39 83.68 .0518 .0903 .0903 .0385 85.89 13 TETRAD X ANCAMINE 2432 Y 10.72 30.51 19.79 56.30 .0569 .1653 .1084 60.28 * Mica is L140-SM-E.

EXAMPLES 14-23 WATER TRANSPORT INTO EPOXY-COATED CR-39 SHEETS AT VARYING MICA CONCENTRATIONS In Examples 14-23, the procedure of Examples 2-13 was followed, using various mica concentrations. In Examples 14-18, the resin : curing agent weight ratio (active basis) was 5 : 3. 3 ; in Examples 19-23, the resin : curing agent weight ratio was 1 : 1. Results are shown in Tables II and III.

TABLE II Using 5250 cm-1 Using 5250/5800 Band Ratio Wet % % Example Curing % Dry Wet Moisture Dry Moisture No. Resin* Agent* Mica IR IR # IR Decrease IR Wet IR # IR Decrease 14 --- --- -- 16.72 68.80 52.08 --- .0834 .3618 .2784 --- CONTROL 15 TETRAD X ANCAMINE 0 15.76 53.63 37.87 27.28 .0793 .2781 .1988 28.59 1856 16 TETRAD X ANCAMINE 5 18.48 33.58 15.10 71.01 .0912 .1667 .0755 72.88 1856 17 TETRAD X ANCAMINE 10 20.98 31.77 10.79 79.28 .0996 .1541 .0545 80.42 1856 18 TETRAD X ANCAMINE 20 23.06 32.18 4.12 82.49 .1030 .1430 .0400 85.63 1856 TABLE III Using 5250 cm-1 Using 5250/5800 Band Ratio Wet % % Example Curing % Dry Wet Moisture Dry Moisture No. Resin* Agent* MIca IR IR # IR Decrease IR Wet IR # IR Decrease 19 --- --- -- 16.16 66.66 50.50 --- .0814 .3522 .2708 --- CONTROL 20 TETRAD X ANCAMINE 0 16.22 65.59 49.37 2.24 .0797 .3384 .2587 4.47 1856 21 TETRAD X ANCAMINE 5 15.90 43.43 27.53 45.49 .0775 .2156 .1381 49.00 1856 22 TETRAD X ANCAMINE 10 18.24 39.17 20.93 58.55 .0894 .1973 .1079 60.16 1856 23 TETRAD X ANCAMINE 20 19.15 34.65 15.50 69.31 .0943 .1738 .0795 70.65 1856

EXAMPLES 24-26 MICA/MODIFIED MICA SEALING COMPOSITION CR-39 flat sheets having various coatings were prepared and tested for moisture absorbance at 50° C and 98% humidity after 48 hours as described above. Results are shown in Table IV below.

TABLE IV Example % Reduction No. Resin Hardener Additive in MR. 24 EPON 8132 TETA---20 (14 phr) * 25 EPON 8132 TETA 30 wt % Mica 50 (14 phr) 26. EPON 8132 TETA 30 wt k L-140-60 (14 phr) SM-E

* parts per hundred, based on active resin Examples 27-32 VARIOUS ADDITIVES CR-39 flat sheets having various coatings were prepared and tested for moisture absorbance at 50°C and 98% humidity after 48 hours as described above. Results are shown in Table V below.

TABLE V Resin : Hardener Weight Ratio (Active basis) = 1 : 1 Example % Reduction No. Resin Hardener Additive in MR. 27 EPON 828 TETA 25 wt % Glass 38 Frit 28 EPON 880 Epi-cure 10 wt % HiSIL 37 3255 T700 29 EPON 880 Epi-cure 10 wt % HiSIL 28 3255 303 30 EPON 880 TETA 9 wt W CrACA* 24

* CrACAC is chromium acetylacetonate.

Example 31 SEALING A NUBBED ELECTROCHROMIC LENS The peripheral edge of a laminated electrochromic lens having a circumferential edge nub aligned with its ion- conducting polymer layer was sealed as follows : Tetrad X and Ancamine 1856 admixtures each containing 20%, by weight, mica, were fed through the inline mixer of an epoxy dispenser and the resulting 5 : 3. 3 w/w epoxy composition was applied via the molding technique of U. S. Pat. Application No. 09/046, 386.

After curing, a mica-enhanced edge seal was present over the nub of the laminated device.

It is evident from the foregoing that various modifications, which are apparent to those skilled in the art, can be made to the embodiments of this invention. Having thus described the invention, it is claimed as follows.