Resin for plastic lens having high-refractive index, lens comprising the resin, and method for preparation of the lens
US5021503A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 1989 |
| Grant date | Jun 4, 1991 |
| Priority date | — |
| Expiry date | Feb 15, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G18/775
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention relates to resin useful in preparing plastic lenses having a high refractive index comprising reacting an aliphatic polyisocyanate compounds having at least one sulfur atom with one or more of active hydrogen compounds selected from the group consisting of a polyol, a polythiol having sulfur atoms only in a mercapto groups, and a polythiol having at least one sulfur atom other than in the mercapto groups; lenses containing the above-mentioned resin; and a method for the preparation thereof characterized by adding an internal release agent to the mixture of the above-mentioned raw materials in casting lenses from the resin; and lenses obtained by this method.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.