GB575675A - Improvements in and relating to the treatment of materials to render them water repellent - Google Patents

Abstract

575,675. Waterproofing. BRITISH THOMSONHOUSTON CO., Ltd. Feb. 25, 1943, No. 3138. Convention date, March 4, 1942. Divided out of 572,919, [Group IV]. [Class 140] Materials are waterproofed by treatment with a solution containing an organo-silicon halide, or a mixture of organo-silicon halides. Alternatively the material may be brought into contact with a liquid organo-silicon halide or a solution thereof in an inert non-reacive diluent, e.g., a liquid hydrocarbon, ether or chlorinated hydrocarbon. The acidity remaining in the treated material may be removed or neutralized by washing with water or a solution of an alkali, e.g., sodium or potassium hydroxide. In example 1, a clean glass surface is brought into contact with a mixture of methyl silicon chlorides consisting mainly of (CH3)SiC13, and (CH3)2SiC12 and is then not wetted by water. Graduated glass tubes, glass fibres or filaments, glass insulators, glazed porcelain insulators, oxidized aluminium foil, and aluminium ice cube trays and dividers may be so treated. Other examples refer to the treatment of porous absorbent paper with an ethereal solution of ethylsilicon trichloride or diethylsilicon dichloride or of both, to the treatment of filter paper with liquid mixtures of phenylsilicon chlorides, to the treatment of a clean glass surface with an ethereal solution of a mixture of methylsilicon bromides and chlorides, and to the treatment of filter paper with a dilute ethereal solution of (a) a mixture of organosilicon compounds boiling above 78‹C. at 12 m.m. pressure and containing C13,SiCH2CH2SiC13, (b) a mixture of C13SiCH2SiHC12 and containing C13SiCH2SiC13, or (c) a mixture of polymeric organo-silicon halides of the type -CH2SiCL2 boiling within the range of 120-137‹C. at 10 m.m. pressure and containing the trimer (CH2SiC12)3. Organo-silicon halides referred to in general are alkylsilicon halides (e.b., ethyl, propyl, and butyl silicon halides), arylsilicon halides (e.g., phenylsilicon halides, aralkylsilicon halides (e.g., phenylmehylsilicon halides, alkarylsilicon halides (e.g., tolylsilicon halides), and compounds such as (CH3)2HSiC1 and similar alkyl and aryl halosilanes. Other neutralizing agents for residual acidity are methylamine, ethylamine, diethyiamine, propylamine, dipropylamine; alkalimetal hydroxides and carbonates, e.g., sodium and potassium hydroxides and carbonates, and calcium hydroxide. Suitable solvents are methyl, ethyl, and propyl ethers, benzene, toluene, gasoline, and chlorinated solvents, e.g., carbon tetrachloride, ethylene chloride, and triethylene chloride. Reaction may occur between the compounds and cellulose, asbestos, and hydrated aluminium oxide. Specifications 572,740, 575,667 and 575,668, [both in Group IV], are referred to.