| 摘要 |
<p>1,155,997. Antistatic coatings. BEXFORD Ltd. 27 Sept., 1967 [30 Sept., 1966], No. 43843/66. Heading B2E. [Also in Division G2] A film base is rendered, antistatic by coating with a layer of a Na, K or Li salt of a copolymer of (i) anα,#-unsaturated dicarboxylic acid or anhydride thereof with (ii) an ethylenically unsaturated co-monomer. Specified acids (i) are maleic, itaconic, citraconic and dimethyl maleic acids. Compounds (ii) may have the general formula CH 2 =CHR'R", a list of suitable groups R', R" being given: specified compounds are ethylene, styrene, vinyl toluene, methyl vinyl ether, ethyl acrylate, methyl methacrylate, acrylamide, vinyl chloride, acrylonitrile, vinyl acetate, isopropenyl acetate. The copolymer salt may contain 20-50 mole % of component (i), with 20-100% of the carboxylic acid functions present in salt form. The coating may be applied in amount above 0.05 mgm/dm<SP>2</SP> by dip- or air-knife coating from aqueous or aqueous/organic media wherein copolymer and an alkali metal hydroxide have been mixed. Specified wetting agents, pigments, supplementary antistatic agents and agents to improve slip characteristics may be included. The film base may be polyethylene terephthalate, polycarbonate or a cellulose ester (e.g. triacetate, secondary acetate, acetate butyrate), each of which may be coated with gelatin or specified polymers. The coated bases may be used in photography (see Division G2) and drafting.</p> |
