Photochromic spironaphthopyran compounds
US5628935A · kind A · utility
12Cited by
1References
25Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 28, 1994 |
| Grant date | May 13, 1997 |
| Priority date | — |
| Expiry date | Oct 28, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D311/96
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A naphthopyran compound represented by the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, and R.sub.10 are each selected from the group consisting essentially of hydrogen, a stable organic radical, a heterocyclic group, a halogen, a nitrogen-substituted group, and a nitrogen-substituted ring compound and wherein A is a substituted divalent aromatic radical that includes substituents selected from the group consisting essentially of hydrogen and the stable organic radical.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.