| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing a low-viscosity urethane resin usable as an adhesive widely ranging from highly adhesive to slightly adhesive levels. <P>SOLUTION: The method for producing the urethane resin comprises the following process: a polyol and a polyisocyanate compound are reacted with each other in such a proportion as to be excess in isocyanate group to obtain an isocyanate group-terminated prepolymer, which is then reacted with a chain extender followed by a terminal terminator. In this method, the chain extender has three or more functional groups reactive with the isocyanate groups, two of the functional groups being selected from a primary amino group, a secondary amino group and a primary hydroxy group, and the rest being selected from carboxy group(s). <P>COPYRIGHT: (C)2006,JPO&NCIPI |
