GB1315225A - Process for preparing a coating of decorative cement - Google Patents

Abstract

1315225 Waterproofed cement coatings ASAHI GLASS CO Ltd and BONNTILE CO Ltd 13 Sept 1971 42660/71 Heading B2E [Also in Division El] A process for preparing a coating of decorative cement, for example to the wall of a building, comprises firstly applying a solution or emulsion of a first synthetic resin to form a water impermeable film on a substrate; secondly coating a fluid, pasty composition prepared by mixing a hydraulic cement, an aggregate powder and a pigment and kneading the mixture; and thirdly coating a layer of a second synthetic resin on the cement layer to form a cured film. If the substrate has a smooth surface a further layer is applied before or immediately after the first synthetic resin layer, which further layer comprises a syntheic resin containing an aggregate. The first synthetic resin, which may be applied by spraying, comprises a polymer of vinylacetate or acrylate or an epoxy resin, or a copolymer of vinylacetate with acrylate or vinylchloride with ethylene. The fluid pasty composition which may be applied by spraying or spreading as a Portland and/or alumina cement mixed with siliceous, sand, ash, diatomaceous earth, or slag, which mix may contain a water repellent such as an aliphatic acid salt, e.g. aluminium stearate, a hardening accelerant such as KNO 3 , AlCl 3 , or CaCl 2 , or a softening agent such as methylcellulose or carboxymethylcellulose. The second resin which may be brushed on may be an acrylate or methacrylate polymer or a copolymer thereof or a copolymer of either with an unsaturated acid or certain given derivatives thereof, e.g. acrylic methacrylic, vinylbenzoic, sorbic, crotonic or vinylcrotonic acid, or with another monomer such as vinyllacetate, styrene, vinylchloride, butadiene, acrylonitrile or vinylidene chloride. A plasticiser may be added, such as dibutyl- or dioctylphthalate. The further layer may comprise a polymer of vinyl acetate, acylic resin, epoxy resin or an emulsion of a synthetic rubber mixed with cement, siliceous sand or stone powder. An additional final coat of a transparent, water repellent, acrylate or silicone paint may be applied to the second synthetic resin layer. The substrate may be concrete, mortar, slate, stone, wood or metal such as iron.