SYNTHETIC LEATHER MANUFACTURING METHOD USING AQUEOUS POLYURETHANE DISPERSIONS

摘要

Disclosed is a method for preparing a synthetic leather, in which a composition including an anionic or cationic aqueous polyurethane dispersion, a water repellent, an emulsifier, an antifoamer and an inorganic filler is impregnated into a substrate, and coated on the substrate, the impregnated and/or coated substrate being then coagulated to form a synthetic leather internally provided with numerous closed cells and having a smooth surface.The aqueous polyurethane-based synthetic leather is obtained by impregnating a composition comprising 100 parts by weight of an aqueous polyurethane dispersion, 0.1 to 5 parts by weight of a water repellant, 0.1 to 8 parts by weight of an emulsifier, 0.1 to 1 part by weight of an antifoamer, and 0.1 to 5 parts by weight of an inorganic filler into a substrate, coating the foamed or defoamed composition on the substrate, and coagulating the coated substrate with a coagulating solution, wherein aqueous polyurethane dispersion is covalently bonded to anionic groups including carboxyl group or sulfonate group, or cationic groups including a tertiary amine group, wherein the coagulating solution is selected from the group consisting of an aqueous solution of various salts, a mixed solution of salt and acid, a mixed solution of salt and base, a mixed solution of acid and base, and mixtures thereof.