THERMOCHROMIC CONTACT LENS

Abstract

A contact lens is shown with patterns of thermochromic coating over the lens. The thermochromic coating is designed to change from colored to clear at just below body temperature in a human ocular surface or about 90 degrees Fahrenheit. As the lens cools in the ambient environment outside the eye, the thermochromic coating changes from clear to colored. The pattern is designed to provide contrasting colors when the contact lens is removed from the eye.

Claims

1. A thermochromic contact lens comprising: (a) a contact lens; (b) a thermally reversible thermochromic material on the contact lens that shifts from a color to colorless at approximately normal human temperature within a human eye.

2. The thermochromic contact lens of claim 1, wherein the thermochromic material is applied to the lens to form a pattern with portions of the pattern of thermochromic material remaining free of thermochromic material and the remaining portions of the pattern including the thermochromic material.

3. The thermochromic contact lens of claim 1, wherein the thermochromic material is applied to the lens to form a pattern with portions of the pattern of thermochromic material comprising thermochromic material that shifts between a first color to colorless and thermochromic material that shifts between a second color to colorless, wherein the first color is visually distinguishable from the second color.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 shows a contact lens with patterns of thermochromic coating over the lens.

DETAILED DESCRIPTION

[0013] Referring to FIG. 1, a contact lens 10 is shown with patterns of thermochromic coating 20 over the lens. The thermochromic coating 20 is designed to change from colored to clear at just below body temperature in a human ocular surface or about 90 degrees Fahrenheit. As the lens cools in the ambient environment outside the eye, the thermochromic coating 20 changes from clear to colored. The pattern is designed to provide contrasting colors when the contact lens is removed from the eye.

[0014] The thermochromic coating 20 should not interfere with any oxygen transfer within the eye. The thermochromic coating 20 should not be drying, so that the eye can maintain the normal and appropriate levels of moisture. Additionally, the thermochromic coating 20 should be hypoallergenic and not cause any type of eye irritations. The thermochromic coating 20 should be suitable for use within the body and not cause any adverse reactions.

[0015] Substrates suitable for use in the preparation of the thermochromic contact lens 10 of the present invention can include any of the plastic optical substrates known in the art and can include non-plastic substrates such as glass. U.S. Pat. No. 7,911,676 teaches a contact lens with photochromic coating applied and is hereby incorporated by reference. Specifically, the '676 patent teaches that “suitable examples of plastic optical substrates, can include polyol(allyl carbonate) monomers, e.g., allyl diglycol carbonates such as diethylene glycol bis(allyl carbonate), which monomer is sold under the trademark CRIK-39 by PPG Industries, Inc; polyurea-polyurethane (polyurea urethane) polymers, which are prepared, for example, by the reaction of an isocyanate-functional polyurethane prepolymer and a diamine curing agent, a composition for one such polymer being sold under the trademark TRIVEXX by PPG Industries, Inc; polyol(meth)acryloyl terminated carbonate monomer; diethylene glycol dimethacrylate monomers; ethoxylated phenol methacrylate monomers; diisopropenyl benzene monomers; ethoxylated trimethylol propane triacrylate monomers; ethylene glycol bismethacrylate monomers; poly(ethylene glycol) bismethacrylate monomers; urethane acrylate monomers; poly(ethoxylated bisphenol A dimethacrylate); poly(vinyl acetate); poly(vinyl alcohol); poly(vinyl chloride); poly(vinylidene chloride); polyethylene; polypropylene; polyurethanes; polythiourethanes; thermoplastic polycarbonates, such as the carbonate-linked resin derived from bisphenol A and phosgene, one such material being sold under the trademark LEXAN; polyesters, such as the material sold under the trademark MYLAR; poly(ethylene terephthalate); polyvinyl butyral; poly(methyl methacrylate), such as the material sold under the trademark PLEXIGLAS, and polymers prepared by reacting polyfunctional isocyanates with polythiols or polyepisulfide monomers, either homopolymerized or co-and/or terpolymerized with polythiols, polyisocyanates, polyisothiocyanates and optionally ethylenically unsaturated monomers or halogenated aromatic-containing vinyl monomers. Also contemplated are copolymers of such monomers and blends of the described polymers and copolymers with other polymers, e.g., to form interpenetrating network products.”

[0016] Further, the substrates may have a protective coating, such as, but not limited to, an abrasion-resistant coating, such as a “hard coat,” on their exterior surfaces. For example, commercially available thermoplastic polycarbonate ophthalmic lens substrates are often sold with an abrasion-resistant coating already applied to its exterior surfaces because these surfaces tend to be readily scratched, abraded or scuffed. An example of such a lens substrate is the GENTEXT™ polycarbonate lens (available from Gentex Optics). Therefore, as used herein the term “substrate” includes a substrate having a protective coating, such as but not limited to an abrasion-resistant coating, on its surface(s).

[0017] Still further, the substrates can be transparent or possess a light influencing property. Suitable optical substrates can be untinted, tinted, linearly polarizing, circularly polarizing, elliptically polarizing, photochromic, or tinted-photochromic substrates. As used herein with reference to substrates the term “untinted” means substrates that are essentially free of coloring agent additions (such as, but not limited to, conventional dyes) and have an absorption spectrum for visible radiation that does not vary significantly in response to actinic radiation. Further, with reference to substrates the term “tinted” means substrates that have a coloring agent addition (such as, but not limited to, conventional dyes) and an absorption spectrum for visible radiation that does not vary significantly in response to actinic radiation.”

[0018] Known reversible organic thermochromic systems consist of a basic color former such as a leuco dye and an acidic developer such as a phenolic compound. In cold, these components are a dark colored salt and upon heating they dissociate above a certain temperature. On cooling the dark colored salt forms again. Reversibly thermochromic compositions are taught in U.S. Pat. No. 9,039,946 and are incorporated herein by reference.

[0019] Accordingly, it is to be understood that the embodiments of the invention herein described are merely illustrative of the application of the principles of the invention. Reference herein to details of the illustrated embodiments is not intended to limit the scope of the claims, which themselves recite those features regarded as essential to the invention.