Photochromic compounds

US5645768A · kind A · utility

Assignee

• Optische Werke G. Rodenstock · DE

Inventors

• Manfred Melzig · Weßling, DE
• Herbert Zinner · Pentling, DE

Key dates

• Filing date: Dec 28, 1995
• Grant date: Jul 8, 1997
• Expiry date: Dec 28, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08K5/1545
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A photochromic compound, in particular, for tinting optical elements made of a plastic material has reduced mobility in plastic material. The photochromic compound is a photochromic 2H-pyran and is distinguished by the aromatic residues being chemically rigidly attached in the 2-position to a spiropyran.