Ultraviolet light filter element
US6872766B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 2002 |
| Grant date | Mar 29, 2005 |
| Priority date | — |
| Expiry date | Nov 22, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K2323/05
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Ultraviolet light absorbing polymer film, coating, or molded article UV filter elements are described which comprise a polymer phase having molecularly dispersed therein a) a first ultraviolet absorbing dibenzoylmethane compound of formula (I) where R1 through R5 are each independently hydrogen, halogen, nitro, or hydroyxl, or further substituted or unsubstituted alkyl, alkenyl, aryl, alkoxy, acyloxy, ester, carboxyl, alkyl thio, aryl thio, alkyl amine, aryl amine, alkyl nitrile, aryl nitrile, arylsulfonyl, or 5-6 member heterocylce ring groups, and b) a second ultraviolet light absorbing compound which absorbs ultraviolet light at a wavelength for which the first compound is deficient at absorbing. In particular embodiments, the second ultraviolet light absorbing compound may comprise a hydroxyphenyl-s-triazine, hydroxyphenylbenzotriazole, formamidine, benzoxazinone, or benzophenone compound. In a specific embodiment of the invention, the above UV absorbing compounds are employed in cellulose acetate film for the fabrication of a protective film for polarizers for use in display applications.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.