Patent · US Active

Photochromic fluorenopyrans with defined dibenzo[B,D]pyrano fused attachment

US9963574B2 · kind B2 · utility

0Cited by

2References

9Claims

0Family size

Assignee

RODENSTOCK GMBH · DE

Inventors

Udo Weigand · Munich, DE
Yven Rohlfing · Munich, DE
Herbert Zinner · Pentling, DE

Key dates

Filing date	Jul 11, 2013
Grant date	May 8, 2018
Priority date	—
Expiry date	Jul 28, 2033

Classification

Technology area (CPC G)Physics
CPC primaryG02C7/102
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

The present invention relates to photochromic fluorenopyrans with defined dibenzo[b,d]pyrano fusion in accordance with general formulae (I) or (II) and to their use in plastics of all kinds, particularly for ophthalmic purposes. The photochromic compounds of the invention are distinguished by two pronounced absorption bands of the open form in the visible wavelength range, meaning that with dye molecules of this kind it is possible to replace two conventional photochromic dyes each having only one discrete absorption band. The compounds of the invention, moreover, have a very good lifetime with very high performance.

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