Blue 3H-naphtho[2,1-b]pyran compounds and use thereof in photochromic articles

US7229989B2 · kind B2 · utility

Assignee

• RODENSTOCK GMBH · DE

Inventors

• Claudia Mann · Munich, DE
• Manfred Melzig · Weßling, DE
• Udo Weigand · Munich, DE

Key dates

• Filing date: Sep 21, 2004
• Grant date: Jun 12, 2007
• Expiry date: Nov 4, 2024

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09K2211/1088
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Photochromic 3H-naphtho[2,1-b]pyran compounds corresponding to formula Iin which the groups R1 to R7 and B′ have defined meanings and the use of such photochromic compounds in synthetic resin articles of all types, particularly for ophthalmic purposes. The photochromic 3H-naphtho[2,1-b]pyran derivatives have particularly long-waved absorption maxima in the open form, and when used in photochromic eyeglass lenses, produce essentially blue color tones which have a high darkening capacity.