GB722484A - Improvements in or relating to organosilicon resins and paints - Google Patents

Abstract

A resinous composition, which air-dries to a tack-free state at room temperature, comprises: (1) the reaction product of 25 to 35 per cent by weight of an organosilicon composition, 20 to 30 per cent of one or more unsaturated fatty acids having 12 to 20 carbon atoms in the molecule, the acid(s) having an iodine number of at least 125, 12 to 18 per cent of glycerine and 25 to 40 per cent of phthalic anhydride, and (2) a solvent for (1). By the term "organosilicon composition" is meant one or more alkoxylated phenylmethylorganosilicon compounds having from 0.8 to 2 silicon bonded alkoxy groups per silicon atom, e.g. phenylmethyldiethoxysilane, phenylmethyldi - isopropoxysilane, mixtures of phenylmethylalkoxysilanes with up to 50 per cent phenyltrialkoxysilanes and partial hydrolysates thereof. Fatty p acids specified are dehydrated castor-, tung-, linseed-, soya bean- and oiticica-oil acids and mixtures thereof. The ingredients may be reacted in any desired manner, but preferably the phthalic anhydride is added after the reaction of the organosilicon composition with the glycerine and the fatty acid. Water and alcohol are removed during the reaction which is effected, e.g. at 100 DEG to 250 DEG C., in the presence or absence of solvents, such as toluene and petroleum naphtha, with which the reaction products are mixed. Pigments e.g titania and ferric oxide, and drying catalysts, e.g. metal naphthenates and octoates such as the octoates of cobalt, manganese and calcium, may also be added. The products are used for pointing asbestos cement sidings of buildings, concrete and brick walls, and cinder blocks. Examples are given. Specification 650,247 is referred to.