Photochromic compound, composition and use thereof
US5246989A · kind A · utility
24Cited by
0References
26Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1991 |
| Grant date | Sep 21, 1993 |
| Priority date | — |
| Expiry date | Mar 28, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C1/685
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A photochromic compound of the present invention is a spiroxazine compound represented by the following formula: ##STR1## wherein R.sup.1 to R.sup.3 represent a monovalent organic group such as alkyl group, Y represents a fused heterocyclic aromatic hydrocarbon group or an unsaturated heterocyclic group if R.sup.1 and R.sup.2 are both methyl groups, and represents an aromatic hydrocarbon group or unsaturated heterocyclic group if R.sup.1 and R.sup.2 are other than the above mentioned. This compound shows an excellent photochromic characteristics even at high temperatures not less than ambient temperature.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.