UV-absorber polymer latex

Disclosed herein are aqueous latices of UV-absorber polymer adapted to forming laminate coatings of visible light transparent, coherent polymeric film and methods of making and using such latices and laminates.

BACKGROUND OF THE INVENTION

Japanese Kokai 57-45169 and 58-38269 disclose solvent polymerization of copolymers containing UV-absorber monomer units useful as coating additives. Specifically disclosed copolymers comprise up to about 22 mole percent (about 30 weight percent) benzotriazole UV-absorbing monomer units an a non-UV-absorbing comonomer such as methyl methacrylate, styrene or butyl acrylate.

U.S. Pat. No. 4,528,311 discloses optically clear UV-absorbing copolymers comprising up to 20 weight percent of 2-hydroxy-5-acrylyloxyphenyl-2H-benzotriazoles for UV-absorbing films that afford 85% absorption at 400 nanometers and 1 millimeter thickness.

U.S. Pat. No. 4,576,870 discloses coextruded laminates comprising UV-absorbing polymer coatings (10-100 microns thick) comprising up to 20 weight percent of 2-hydroxyphenylbenzotriazole monomers.

U.S. Pat. Nos. 4,785,063 and 4,892,915 disclose incorporation of 2-(2-hydroxy-5-acryloyloxyalkyl)-phenyl-2H-benzotriazoles UV-absorbing copolymerizable additives at low levels, e.g. at about 2 percent, in acrylate coatings which are cured by E-beam radiation.

U.S. Pat. No. 4,927,891 discloses acrylic coating resins with up to 20 weight percent hydrazide functionalized light stabilizers, e.g. hindered amine light stabilizers, 2-hydroxybenzophenones, 2-(2-hydroxyphenyl)-2H-benzotriazoles, aryl salicylates and oxalanilides.

EPO 0 282 294 discloses optically clear silicone polymers containing vinylsilylalkoxy arylbenzotriazole monomer units.

U.S. Pat. Nos. 3,745,010 and 3,761,272 disclose emulsion polymerized, UV Absorbers benzotriazole acrylate copolymers useful in photographic applications, e.g. to protect photographic film against UV radiation. Copolymers, e.g. of methylmethacrylate or butylacrylate and 2-70% benzotriazole-functionalized methacrylates, are useful at up to 40% by weight in UV-absorbing layers. For instance, glass coated with gelatin and emulsions of such UV-absorbing copolymers provided photographic filters having a maximum absorption at 352 nm.

U.S. Pat. Nos. 4,612,358 and 4,652,656 disclose UV-absorbing copolymers of 20-60 percent benzotriazole-functionalized acrylamides useful for protective layers for UV sensitive plastics. Bulk polymerized copolymers comprised methyl methacrylate and 20 weight percent benzotriazole monomer. Emulsion polymerized copolymers comprising methylmethacrylate and 50 weight percent benzotriazole monomer were prepared in large particle size (100 micron). Such UV-absorbing copolymers are said to be useful for providing a UV protective layer for a UV sensitive plastic.

U.S. Pat. Nos. 4,443,534 and 4,455,368 disclose UV-absorbing copolymer latex useful in UV-absorbing protective layers for photographic film, e.g. light sensitive silver halide material.