| 摘要 |
<p>Paper &c. is coated with a pigment &c. and a binder comprising a copolymer of at least one alkyl acrylate and 2.5 to 7 per cent of at least one amide of methacrylic, acrylic, itaconic, aconitic, maleic, or fumaric acid, the said copolymer having a transition or inflection temperature of its modulus of rigidity of e.g. -45 DEG to 20 DEG C. The alkyl group of the alkyl acrylate may have 1 to 4 carbon atoms. The copolymer may also include a hardening comonomer consisting of a lower alkyl methacrylate and styrene, acrylonitrile, methacrylonitrile, vinyl chloride, or vinylidene chloride, e.g. there may be 64 per cent of ethyl acrylate, 0 to 33.5 of methyl methacrylate and 2.5 to 7 of methacrylamide or acrylamide. Anionic or nonionic emulsifying agents, and peroxide free-radical catalysts may be included; and the pH value may be adjusted, as by adding sodium hydroxide, to 8.5 to 9.5 to aid in dispersing clay in the coating mixture. Other binders, e.g. casein, soya protein, chlorinated starch, or hydroxyethyl starch may be included. Specification 802,039 is referred to.</p> |
