Coating composition and optical mar-resistant tintable coating
A coating composition and coating for ophthalmic lenses and other polymeric substrates having a unique combination of excellent solution stability, rapid cure rate, improved mar resistance, rapid dye absorption, and improved receptivity towards antireflective coatings. The coating comprises an abrasion resistant polymer and a dye-absorption-enhancing oligomer. The coating is tinted after curing with a dye to provide light absorbency in the coating.
1. A method of providing a coated mar resistant layer on a polymeric article having at least one exposed surface comprising coating a composition onto the exposed surface of the polymeric surface, the composition comprising:
a) at least one organofunctional trialkoxysilane monomer in the amount of from 20 to 80 percent by weight of the composition, said trialkoxysilane monomer having the formula
where R 1 , R 2 , and R 3 are independently selected from alkyl groups of 1 to 8 carbon atoms;
n is an integer 1 through 6, inclusive,
and X is selected from the group consisting of glycidyl, acrylate, methacrylate, acrylantide, methacrylamide, N-methylacrylaniide, N-methylmethacrylamide, vinyl, and allyl;
b) water to hydrolyze at least one third of alkoxy groups of the trialkoxysilane monomer; and
c) from 1.0 to 25.0 percent by weight at least one oligomeric tintability enhancer polymerizing at least the trialkoxysilane component of the composition to form a polymerized coating, immersing the polymeric article in an aqueous solution of disperse dye so that the mar resistant layer is directly exposed to the aqueous solution, and absorbing sufficient dye into the polymerized coating to absorb at least 70% of incident visible radiation at a maximum wavelength of absorption of the disperse dye.
2. A method according to claim 1 wherein the oligomeric tintability enhancer has a solubiloity for at least one disperse dye so that the disperse dye is at least 5× more by weight absorbed into the dye-absorbing enhancer than the same disperse dye is absorbed by a polymer consisting of units derived from the organofunctional trialkoxysilane under dye-tinting conditions of immersion in a hot aqueous solution of 95° C. with 0.2% by weight dye/water.
3. A method according to claim 1 wherein the oligomeric tintabiity enhancer is selected from the group consisting of polyester polyol, urethane polyol, acrylic polyol, and acrylated polyurethane.
4. A method according to claim 2 further comprising from 1.0 to 10.0 percent by weight of one or more photoinitiators independently selected from free radical and cationic photoinitiators.
5. A method according to claim 2 further with the coating composition further comprising and organic solvent.
6. The method of claim 1 wherein the aqueous solution is at a temperature of between 85 and 99° C.
7. The method of claim 6 wherein sufficient disperse dye is absorbed to absorb at least 80% of incident visible radiation at a maximum wavelength of absorption of the disperse dye.
8. The method of claim 6 wherein polymerizing causes the alkoxysilane to react with the oligomeric tintability enhancer.
9. The method of claim 1 wherein X comprises glycidyl.
10. A method of providing a coated mar resistant layer on an article consisting of polymeric ophthalmic lens having at least one exposed surface, the exposed surface having a single coating layer thereon comprising coating a composition comprising:
where R 1 , R 2 , and R 3 are independently selected from alkyl groups of 1 to 8 carbon atoms;
n is an integer 1 through 6, inclusive,
and X is selected from the group consisting of glycidyl, acrylate, methacrylate, acrylamide, metbacrylaniide, N-methylacrylamide, N-methylmethacrylamide, vinyl, and allyl;
b) water to hydrolyze at least one third of alkoxy groups of the trialkoxysilane monomer; and
c) from 1.0 to 25.0 percent by weight at least one oligomeric tintability enhancer onto the exposed surface of the polymeric surface, polymerizing at least the trialkoxysilane component of the composition, to form a polymerized coating immersing the polymeric article in an aqueous solution of disperse dye so that the mar resistant layer is directly exposed to the aqueous solution, and absorbing sufficient dye into the polymerized coating to absorb at least 70% of incident visible radiation at a maximum wavelength of absorption of the disperse dye.
11. The method of claim 10 wherein X comprises glycidyl.
12. A method according to claim 9 wherein the oligomeric tintability enhancer is selected from the group consisting of polyester polyol, urethane polyol, acrylic polyol, and acrylated polyurethane.
13. A method according to claim 10 wherein the oligomeric tintability enhancer is selected from the group consisting of polyester polyol, urethane polyol, acrylic polyol, and acrylated polyurethane.
14. A method according to claim 9 wherein the oligomeric tintabiity enhancer comprises a polyester polyol.
15. A method according to claim 10 wherein the oligomeric tintability enhancer comprises a polyester polyol.
16. A method according to claim 11 wherein the oligomeric tintability enhancer comprises a polyester polyol.
17. A method according to claim 12 wherein the oligomeric tintability enhancer comprises a polyester polyol.
18. The method of 17 wherein the aqueous solution is at a temperature of between 85 and 99° C.