PRODUCING METHOD OF WATER-BASED POLYURETHANE, WATER-BASED POLYURETHANE THEREBY AND PRODUCING METHOD OF PRODUCT USING WATER-BASED POLYURETHANE

摘要

Provided are a method for preparing a water-dispersible polyurethane, a water-dispersible polyurethane composition prepared by the method which can be applied to a product without pretreating process, and a method for preparing a product by using the water-dispersible polyurethane. A water-dispersible polyurethane is prepared by reacting 60-70 wt% of glycol, 10-20 wt% of isocyanate and 3-7 wt% of ionic center in the presence of a catalyst at 90-150 deg.C for 30 min or more; adding 7-13 wt% of isocyanate and reacting the mixture in the presence of a catalyst at 80-150 deg.C for 40-60 min; adding 3-6 wt% of a neutralizer and reacting the mixture at 50-150 deg.C for 20-120 min; adding 200-250 wt% of water, stirring the mixture and stabilizing it for 10-60 min; and adding 1-5 wt% of amine in a form of 10 wt% aqueous solution, reacting the mixture for 30 min or more, adding water so as to allow the solid part to be 20-25 wt%, and stirring the solid in the water.