| 摘要 |
PROBLEM TO BE SOLVED: To provide a simple and economical method for commercially manufacturing a polymeric MDI that has good reactivity, little amount of impurities such as acidic materials and hydrolyzable chlorine, very good color that is provided by decolorizing a discolored product, and that is extremely slow in discoloration. SOLUTION: A compound having a trialkoxysilane structure in a molecule is added to a polymeric MDI in an amount of 0.001-10 % by mass, followed by heating at 30-220°C, so as to decrease the discoloration of the MDI. COPYRIGHT: (C)2004,JPO
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