WATER-REPELLING AGENT FOR FIBER

PURPOSE:To produce a water-repelling agent capable of applying water repellency excellent in durability to a fiber by conducting a radical polymerization of a specified organopolysiloxane and another monomer radical-copolymerizable therewith. CONSTITUTION:Application of water repellency excellent in durability is readily carried out by synthesizing a copolymer through a radical polymerization of an organopolysiloxane compound having one radical-polymerizable group in one molecule and represented by the formula [R is H or methyl; R is a 1 to 12C divalent hydrocarbon which may be rntercepted by O; R is methyl or trimethylsiloxy; R is a 1 to 4C univalent hydrocarbon; (n) is 3 to 200; (m) is 1 to 3] and radical-polymerizable monomers composed mainly of an acrylate and/or a methacrylate preferably according to the solution polymerization method, dissolving the obtained copolymer in an alcohol and immersing a natural or synthetic fiber in the resultant solution. Since this water-repelling agent is dissolved in a nontoxic alcohol such as ethanol or isopropanol, it is suitably used in the form of an aerosol by using a propellant gas.