still for beleggning of a cementhaltig product

摘要

1484622 Coating cementitious products KUBOTA TEKKO KK (KUBOTA Ltd) and DAI NIPPON TORYO KK (DAI NIPPON TORYO CO Ltd) 17 Sept 1974 40573/74 Heading B2E A method of coating a cementitious product comprises applying to at least one surface thereof an aqueous emulsion of a copolymer of (a) 98-15% by weight of two or more alkyl (meth)acrylates having 1-8 carbon atoms in the alkyl group, (b) 2-25% of at least one comonomer containing a carboxyl, hydroxyl, epoxy, N-methylol or N-alkoxymethyl group, and (c) 0-60% of at least one comonomer selected from styrene, alphamethyl styrene, vinyl toluene, vinyl acetate, vinyl propionate and vinyl esters of synthetic fatty acids having 9-11 carbon atoms; drying the coated surface; and then curing the dried coating by heating with steam at 80-220‹C at atmospheric or elevated pressure up to 10 kg/cmSP2/SP. The coating may also comprise a water-soluble amino resin (e.g. a melamine resin) or an oxide, hydroxide or organic acid salt of Mg, Ca, Zn, Ba, Al, Ti, Pb, Cr, Co or Ni. The coating provides the cementitious product with improved resistance to chemicals, reduced penetration by water, and enhanced weather resistance. The cementitious product may contain inorganic fibrous material such as asbestos, glass fibre, rock wool or slag wool, or organic aggregates such as polypropylene or pulp. Examples illustrate the coating of asbestos-cement sheets.