Photochromic article
Describes an article, e.g., an optical article such as a lens, in which the article includes (a) a rigid substrate, e.g., a transparent ophthalmic substrate, such as a thermoset or thermoplastic substrate, having at least one surface suitable for accommodating a photochromic coating, and (b) a transparent photochromic coating comprising dendritic polymeric acrylate, e.g., polyester acrylate, on at least a portion of said surface of the substrate, the coating comprising a photochromic amount of at least one photochromic material, e.g., an organic photochromic material.
1. An article comprising:
(a) a rigid substrate having at least one surface suitable for accommodating a photochromic coating, and
(b) a transparent photochromic coating on at least a portion of said surface of said substrate, said coating formed from a photochromic coating composition comprising dendritic polymeric acrylate, from 0.5 to 16 weight percent of at least one adhesion promoting organo-silane material, and a photochromic amount of at least one photochromic material.
2. The article of claim 1 wherein the dendritic polymeric acrylate is chosen from acrylate modified dendrimers chosen from epoxide-amine dendrimers, carbosilane-based dendrimers, amido amine dendrimers, polysulfide dendrimers, polysiloxane dendrimers, polyaminosulfide dendrimers, polyether dendrimers, polythioether dendrimers, polyester dendrimers, polyester amide dendrimers, or poly (ether ketone) dendrimers.
3. The article of claim 1 wherein the dendritic polymeric acrylate is dendritie polyester aerylate.
4. The article of claim 3 wherein the dendritic polyester acrylate is prepared from a liquid composition prepared by acrylating a dendritic polyester macromolecule and an organic alcohol having a molecular weight of less than 2000.
5. The article of claim 1 wherein the substrate is chosen from substrates prepared from polymerizable compositions comprising allyl diglycol carbonate monomer(s), substrates prepared from polymerizable compositions comprising acrylic functional monomers, substrates prepared from compositions comprising thermoplastic polycarbonate, substrates prepared from compositions comprising poly(urea urethane), substrates prepared from compositions comprising polythiourethanes, substrates prepared from compositions comprising polyurethanes, or substrates prepared from compositions comprising the reaction product of polyflmnctional isocyanate(s) and/or isothiocyanate(s) with polythiol or polyepisulfide monomer(s)
6. The article of claim 1 wherein the transparent photochromic coating is prepared from a curable coating composition comprising dendritic polyester acrylate and at least one other radiation curable acrylic material.
7. The article of claim 6 wherein the at least one other radiation curable acrylic material is chosen from monoacrylates and polyacrylates.
8. The article of claim 7 wherein the polyacrylate is a diacrylate, triacrylate or mixture of diacrylate(s) and triacrylate(s).
9. The article of claim 6 wherein the weight ratio of the dendritic polyester acrylate to the other radiation curable acrylic monomeric material(s) ranges from 90:10 to 10:90.
10. The article of claim 6 wherein the weight ratio of the dendritic polyester acrylate to the other radiation curable acrylic monomeric material(s) ranges from 70:30 to 30:70.
11. The article of claim 6 wherein the curable composition used to prepare the photochromic coating further comprises at least one other radiation curable monomeric material containing polymerizable group(s) other than acrylic functional groups, said at least one other radiation curable monomeric material being present in amounts of up to 20 weight percent of said composition.
12. The article of claim 1 wherein the photochromic material comprises at least one organic photochromic material.
13. The article of claim 12 wherein the organic photochromic material is chosen from materials comprising pyrans, chromenes, oxazines, fulgides, fulgimides, metal dithizonates, diarylethenes and mixtures of such organic photochromic materials.