Photochromic spiropyran compounds
US4826977A · kind A · utility
163Cited by
6References
11Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 15, 1987 |
| Grant date | May 2, 1989 |
| Priority date | — |
| Expiry date | May 15, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K5/1545
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A series of novel photochromic spiropyrans are disclosed in which a spiro-adamantane group is introduced into the 2-position of the benzopyran or naphthopyran ring. The spiropyran compounds of the invention exhibit heliochromic properties, i.e. they color in sunlight and fade rapidly at ambient temperatures in the absence of U.V. light, making them good candidates for use in the manufacture of sunglasses. The invention includes lenses which darken in sunlight and incorporate the novel spiropyrans and a process for the preparation of the spiropyran compounds.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.