Organic photochromic materials with high refractive index, their preparation and articles formed from these materials
US5763511A · kind A · utility
10Cited by
2References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 21, 1997 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Apr 21, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K9/02
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention relates to organic photochromic materials consisting of a polymer matrix of optical quality and of at least one dye that imparts photochromic properties to the matrix, the dye being selected from spirooxazines, spiropyrans and chromenes. The polymer constituting the matrix is a copolymer of 30-95 wt % ethoxylated bisphenol A dimethacrylate and 5-70 wt % of a polyurethane oligomer having terminal di- or triacrylic or di- or trimethacrylic functionality. Such photochromic materials are most suitable for the production of ophthalmic and sun protection lenses.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.