Patent · US Expired

Photochromic naphtho [2,1-b]pyran compounds containing bithienyl or terthienyl substituents, process for their manufacture, and photochromic materials and articles obtained

US6312811A · kind A · utility

76Cited by
1References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 8, 1999
Grant dateNov 6, 2001
Priority date
Expiry dateJul 8, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31504
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

The photochromic compounds of the invention correspond to the formula: ##STR1## in which Th.sub.2 represents a bithienyl group in one of the positions 5 to 10 of the naphthenic ring system system, R.sup.1 denotes a bithienyl or trithienyl group and R.sup.2 denotes a bithienyl, trithienyl, aryl, naphthyl, thienyl, furyl, pyrrolyl or N-alkylpyrrolyl group.

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