| 摘要 |
PROBLEM TO BE SOLVED: To obtain a composition which is free from leaving of the adhesive when the coated material is peeled off by blending a polyfunctional isocyanate compound with a polyurethane polyol having terminal hydroxyl groups, obtained through the reaction of a polyester polyol, a polyether polyol and an organic polyisocyanate in the presence of a specified number of organometallic catalysts different in valence. SOLUTION: The organometallic catalysts used for obtaining the polyurethane polyol having terminal hydroxyl groups comprise two organometallic catalysts different in valence, preferably divalent and tetravalent catalysts. The divalent organometallic catalyst used preferably comprises tin 2-ethylhexanoate. It is desirable to blend it in an amount sufficient to provide a ratio of tin 2- ethylhexanoate to the tetravalent organometallic catalyst (e.g. dibutyltin diacetate) of less than 1:1, preferably (0.2 to 0.8):1. It is desirable that part of the polyols comprising polyester polyols and polyether polyols have a molecular weight of 2,000 to 4,000 and are trifunctional.
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