Patent · US Expired

Photochromic chromene derivatives

US5702645A · kind A · utility

14Cited by
13References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 30, 1995
Grant dateDec 30, 1997
Priority date
Expiry dateOct 30, 2015

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07D493/04
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Described herein are photochromic compounds or a structural isomer of the photochromic compound, the photochromic compounds represented by the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.4, R.sub.5, R.sub.6, R.sub.8, A, B, C, and D are each selected from the group consisting essentially of hydrogen, a stable organic radical, a heterocyclic group, halogen, a nitrogen-substituted radical, and a nitrogen-substituted ring radical.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.