Photochromic compound and articles containing the same
US4637698A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 1984 |
| Grant date | Jan 20, 1987 |
| Priority date | — |
| Expiry date | Jul 30, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C1/685
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Photochromic compounds represented by the graphic formula: ##STR1## wherein: (a) R.sub.1 is selected from the group consisting of C.sub.1 -C.sub.8 alkyl, phenyl, phen(C.sub.1 -C.sub.4) alkyl, allyl and mono- and di-substituted phenyl, said substituents being selected from C.sub.1 -C.sub.4 alkyl and C.sub.1 -C.sub.5 alkoxy; PA0 (b) R.sub.2 and R.sub.3 are each selected from the group consisting of C.sub.1 -C.sub.5 alkyl, phenyl, C.sub.1 -C.sub.4 alkyl and C.sub.1 -C.sub.5 alkoxy mono- and disubstituted phenyl, benzyl or combined to form a cyclic ring selected from the group consisting of an alicyclic ring containing from 6 to 8 carbon atoms (including the spiro carbon atom), norbornyl and adamantyl, and PA0 (c) R.sub.4 and R.sub.5 are each selected from the group consisting of hydrogen, C.sub.1 -C.sub.5 alkyl, halogen, C.sub.1 -C.sub.5 alkoxy, nitro, cyano and C.sub.1 -C.sub.8 alkoxycarbonyl are described. Solvent systems which form photochromic compositions with the above compounds and articles containing the photochromic compound are described. The compound or compositions typically change from a colorless (nonexcited) or pale color, e.g., yellow, to blue after exposure to ultravi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.