Light-absorbing filters

light-absorbing filters comprise a self-supporting polymeric film, such as an oriented polyethylene terephthalate film, containing or coated with a lacquer containing a compound which absorbs light in the wavelength band less than 0.4 .mu.m (i.e. UV light). The filters are particularly useful as UV-absorbing filters for use in flashbulbs for color photography. Suitable light-absorbing compounds are hydroxyphenyl benzotriazoles, e.g. 2(2'-hydroxy-3',5'-di-t-amylphenyl)benzotriazole, and hydroxy-substituted benzophenone, e.g. 2,2'-dihydroxy-4,4'-dimethoxy-benzophenone.

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Description
Patent History
Patent number: T969004
Type: Grant
Filed: May 2, 1977
Date of Patent: Apr 4, 1978
Assignee: Imperial Chemical Industries Limited (London)
Inventor: Bruce Martin Watkiss (Welwyn)
Application Number: 5/792,502
Classifications
Current U.S. Class: 96/27R; 350/11; Plural Light Sources Or Light Source Supports (362/11)
International Classification: G03C 504; G03B 520; G03B 1502;