| 摘要 |
PROBLEM TO BE SOLVED: To provide a preparation process of a polyurethane emulsion for an aqueous one component coating agent, which is environmentally safe and excellent in properties such as productivity, storage stability, water-proofing of its coated film and resistance to solvents. SOLUTION: The preparation process of the polyurethane emulsion for the aqueous one component coating agent comprises: reacting an organic diisocyanate (a1), a polymer polyol (a2), and a carboxyl group-containing low molecular glycol (a3) to form a urethane polymer (A) with a terminal of an isocyanate group containing a carboxylic group; mixing (A) with a nonanionic polyisocyanate (B); blocking the whole or a part of isocyanate groups of the above mixture by a block agent (C); neutralizing the carboxylic group in the system with a neutralizer (D); and finally emulsifying the above mixture in water and, if necessary, performing a chain extending reaction of the system. COPYRIGHT: (C)2005,JPO&NCIPI
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