WATERPROOF CLOTH AND ITS PREPARATION

摘要

PROBLEM TO BE SOLVED: To produce a waterproof cloth which possesses excellent high frequency weldability, water resistance and mechanical strength, is lightweight and easy to handle, can be recycled and is environmentally friendly and to provide a process for preparing the same. SOLUTION: A backing fabric, which has been woven with filaments of a polyester fiber, is coated with a copolymer polyester emulsion or dispersion prepd. by copolymerizing an acid moiety of terephthalic acid and isophthalic acid or an aliph. dicarboxylic acid with an alcohol moiety of a 2-6C straight- chain glycol and a 2-6C branched glycol or ether glycol to prepare a mixed polyester having an intrinsic viscosity of 0.4 to 1.5, melt-mixing the mixed polyester with a nonionic surfactant having an HLB value of 15 to 20, and dispersing the mixture in water or an aq. amine soln. to regulate the solid content to not less than 25% and the soln. viscosity to not less than 1000cps. The coated fabric can be subjected to high-frequency welding, and the weld has a bonding strength of not less than 60% relative to the tensile strength of the coated fabric. Further, it has a watertightness of not less than 1,000mmH2 O.