Patent ID: 11874534
Assignee: CARL ZEISS VISION INTERNATIONAL GMBH
Field: Optics (Instruments)
Classification: CPC G  B | IPC G

Claim 30:
31. A method of producing a spectacle lens having at least one substrate and at least one photochromic layer, the method comprising:
a) providing at least one substrate to be coated,
b) coating at least one surface of the substrate to be coated with at least one photochromic layer,
c) covering the spectacle lens obtained in step b), on the same surface of the substrate as in step b), remotely from the substrate, with at least one chemically modified layer which displays a pH-buffering effect and which is produced using a coating composition containing:
i) at least one of:
an aqueous aliphatic, cycloaliphatic, aromatic, or heteroaromatic polyurethane dispersion;
an aqueous aliphatic, cycloaliphatic, aromatic, or heteroaromatic polyurea dispersion;
an aqueous aliphatic, cycloaliphatic, aromatic, or heteroaromatic polyurethane-polyurea dispersion; or
an aqueous aliphatic, cycloaliphatic, aromatic, or heteroaromatic polyester dispersion;

ii) at least one solvent;
iii) at least one base; and
iv) optionally, at least one additive; and

d) bonding the same surface of the spectacle lens obtained in step c) to at least one ultrathin lens of average thickness in a range of 19 μm to 230 μm.