| 摘要 |
<p>1,242,640. Coated products. E. I. LU PONT DE NEMOURS & CO. 16 Oct., 1969 [22 Oct., 1968], No. 50830/69. Heading B2E. [Also in Division C3] Vapour permeable glossy sheet materials consist essentially of (a) a microporous fibrous substrate having adhered thereto (b) a glossy vapour permeable non-porous codensced coating from 0.- to 1.5 mil thick which coating consists essentially of (1) 10 to 99.9% by weight, based on the total weight of the polymer of the coating of an isocyanate terminated polyurethane which is the reaction product of an organic diisocyanate and an active hydrogen containing poly(alkylenether)glycol or polyester; (2) from 0 to 25% by weight, based on the total weight of polymer, of a vinyl chloride polymer; and (3) 0.1 to 1.0% by weight, based on the weight of the polymer, of a reactive polysiloxane of the formula: wherein R 1 is -H or an alkyl group having 1 to 4 carbon atoms, and R 2 is -NCO, -NH 2 , -H or -OH, and n is an integer sufficiently large to give the polysiloxane an inherent viscosity (measured in methyl ethyl ketone) of from 0.1 to 2.0 at 25‹C. The microporous fibrous substrate may be natural leather or a synthetic microporous sheet material. Suitably the synthetic material is a porous web of a synthetic polymeric material reinforced with fibres and having adhered thereto a microporous synthetic polymer coating. The porous web is preferably a fibrous mat, e.g. of non- woven, needle punched, heat shrunk polyethylene terephthalate fibres, impregnated with a polymeric material, e.g. a polyurethane. In a typical Example, such a substrate coated with a microporous polyurethane is dyed black and then dip coated with a non-porous coating composition on the exposed microporous polyurethane surface. After drying the coated material is embossed.</p> |
