Temperature stable and sunlight protected photochromic articles
US5973039A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 21, 1997 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Apr 21, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B1/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The invention relates to photochromic transparent organic materials particularly useful for the production of photochromic organic ophthalmic lenses. The material includes an optical-quality polymer matrix and at least one coloring agent giving photochromic properties to the matrix. The coloring agent is chosen from the group of the spirooxazins the spiropyrans, and the chromenes. The polymer of the matrix is chosen from the group of homopolymers of ethyoxylated bisphenol A dimethacrylate with formula I: ##STR1## in which R is H or CH.sub.3, and m and n independently represent 1 or 2, and of the copolymers of this dimethacrylate containing at most 30 wt % of an aromatic monomer with vinyl, acrylic or methacrylic functionality.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.