Photochromic naphthopyran compounds
US5759450A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1996 |
| Grant date | Jun 2, 1998 |
| Priority date | — |
| Expiry date | Jul 31, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/23
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A naphthopyran compound represented by the formula: ##STR1## wherein R.sub.5, R.sub.6, R.sub.8, R.sub.9, and R.sub.10 are each selected from hydrogen, a first stable organic radical, an organic heterocyclic group, halogen, a first nitrogen-substituted group, and a first nitrogen-substituted ring compound; A and B are each selected from hydrogen, substituted phenyl, and substituted naphthyl, provided that at least one of A or B is substituted phenyl or substituted naphthyl; and any substituent of any substituted phenyl or substituted naphthyl at A or B is selected from hydrogen, a second stable organic radical, an organic heterocyclic group, halogen, a second nitrogen-substituted group, and a second nitrogen-substituted ring compound, provided that at least one substituent of any substituted phenyl or substituted naphthyl at either A or B is phenyl, naphthyl, or furyl.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.