High-refractivity plastic lens resin formed from a polyisocyanate and a polythiol
US4791185A · kind A · utility
31Cited by
4References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 5, 1987 |
| Grant date | Dec 13, 1988 |
| Priority date | — |
| Expiry date | Nov 5, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B1/041
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Disclosed herein is a colorless transparent plastic lens having high refractivity and low dispersion. The lens is light, has heat resistance sufficient for post processing, and is excellent in grinding machinability and impact resistance. It is made of a sulfur-containing urethane resin, which is a polymer of a specific polythiol and a particular polyisocyanate of at least bifunctionality.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.