Patent · US Expired

Photochromic compound and articles containing the same

US4931219A · kind A · utility

118Cited by
6References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 12, 1989
Grant dateJun 5, 1990
Priority date
Expiry dateJun 12, 2009

Classification

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

Abstract

Described are spiro (benzidoline) pyrido benzoxazine and spiro (benzindoline) naphthoxazine photochromic compounds and their use in plastic hosts to impact a photochromic response thereto.

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