GB810310A - Improvements relating to water-repellent materials - Google Patents

Abstract

A process of imparting water-repellency to a material as article comprises treating the same with a liquid organopolysiloxane, or with a solution as an emulsion of an organopolysiloxane and irradiating the thus treated material or article with high energy particles. Organopolysiloxanes containing any of the following radicales may be used: methyl, ethyl, butyl, isobutyl, octyl, cyclohexyl, cycloheptyl, phenyl, diphenyl, naphthyl, tolyl, xylyl, ethylphenyl, benzyl, phenylethyl, chlorophenyl, dibromophenyl, vinyl or alkyl. Specified diluents are benzene, toluene, xylene, dioxane, ethanol and propanol. The organopolysiloxanes may also be extended by the formation of aqueous emulsions. Specified emulsifying agents are sulphonated amide condensation <PICT:0810310/III/1> products of fatty acids with organc amines, sulphonated aromatic and mixed alkyl aryl sulphonate derivates, sulphonated ester derivatives, trimethyl benzyl ammonium chloride and hexadecyldimethylbenzyl ammonium chloride. The organopolysiloxane either undiluted, in solution or emulsified is applied in liquid form to the material to be treated by dipping, spraying or by means of a padder or quetch. Materials which may be treated are cloths of cotton, linen, silk, wool, nylon, orlon, viscose or acetate rayon, also paper, cardboard or leather. As shown, apparatus 1 produces a beam of high energy electrons which pass through metal tube 4 and emerge through end window 7 to impinge upon and irradiate a sheet 10 of material treated with an organopolysiloxane in accordance with the invention. The electron beam may be focused by means of winding 8 energized by D.C. source 91 through variable resistance 9. Sheet 10 may be in the form of strip material passed continuously under window 7. Irradiation may be carried out in an atmosphere of nitrogen or an inert gas. Examples describe the treatment of fabric and paper with an organopolysiloxane prepared from a mixture of decamethyltetrasiloxane, octamethylcyclotetrasiloxane and caustic potash. Specifications 594,481, [Group IV] 618,453, 632,955 and 640,067, [all in Group IV (a)], are referred to.ALSO:In rendering fibrous materials water-repellent a curable or convertible siloxane is used in undiluted solution or emulsion form to treat the material, and the thus-treated material is irradiated with high energy particles. Organopolysiloxanes containing e.g. from 1.25 to 2.25 per Si atom of any of the following radicals may be used: methyl, ethyl, butyl, isobutyl, octyl, cyclohexyl, cycloheptyl, phenyl, diphenyl, naphthyl, tolyl, xylyl, ethylphenyl, benzyl, phenylethyl, chlorophenyl, dibromophenyl, vinyl or alkyl. Specified diluents are benzene, toluene, xylene, dioxane, ethanol and propanol. The organopolysiloxanes may also be extended by the formation of aqueous emulsions. Specified emulsifying agents are sulphonated amide condensation products of fatty acids with organic amines, sulphonated aromatic mixed alkyl aryl sulphonated derivatives, sulphonated ester <PICT:0810310/IV (a)/1> derivatives, trimethyl benzyl ammonium chloride and hexadecyldimethylbenzyl ammonium chloride. Organosilicon compounds of the general formula <FORM:0810310/IV (a)/1> may be incorporated into the treating solution, wherein R1 is a monovalent hydrocarbon radical (e.g. alkyl, such as methyl, ethyl or propyl; alkenyl, aryl, aralkyl or alkaryl), x has a value from 1.0 to 1.5, y has a value from 0.7 to 1.25 and the sum of x and y has a value from about 2.0 to 2.25 inclusive. Irradiation may be carried out in an atmosphere of nitrogen or an inert gas. Examples describe the treatment of fabric and paper with an organopolysiloxane prepared from a mixture of decamethyltetrasiloxane, octamethylcyclotetrasiloxane and caustic potash. Specifications 594,481, [Group IV], 618,453, 632,955 and 640,067 are referred to.