Patent · US Expired

Photochromic compound and articles containing the same

US4986934A · kind A · utility

18Cited by
11References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 21, 1988
Grant dateJan 22, 1991
Priority date
Expiry dateDec 21, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09K9/02
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

Described are spirobenzoxazine pyrrolo pyridine compounds. Also described is the use of such compounds as photochromic substances in organic host materials such as an organic transparent plastic material, e.g., an ophthalmic lens, to impart a photochromic response thereto.

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