| 摘要 |
A compsn. for treating the surface of a support comprises an aq. soln. of (a) 20-40 wt.% of gelatin and anti-gelling agent, (b) 20-50% of a vinyl or acrylic (co)polymer, (c) 20-30% of a 3-5% aq. soln. of starch, and (d) 10-20% of a 4-7% aq. soln. of a cellulose cpd.. The soln (a) pref. contains 20-40 wt.% of dry gelatine extract and 20-30% of anti-gelling agent, the rest being water. The vinyl polymer (b) is a polyvinyl acetate. The cellulose deriv. (d) is an alkyl- or carboxymethyl-cellulose. The compsn. contains 1.5 wt.% of an anti-blister agent, 2.5% of a preservative, and a water-sol. dye or opacifier. USE/ADVANTAGE - The support is plaster, a plaster slab, concrete, cement, brick or wood (claimed). An insulating material is bonded onto a support by a comspn. comprising 40-60 wt.% of the compsn. and 60-40% of a mineral filler, esp. calcite or marble powder of grain size 5-100 microns (claimed). The surfaces are esp. used in building and may later be painted, varnished or papered. The compsn. is free from organic solvents and gives a hard, uniform, smooth and impermeable surface. It is economical, with 1kg covering 14m2, compared with 4-5 m2 for a known hardening compsn.
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