| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a composition capable of forming a surface-protecting layer excellent in abrasion resistance by compounding a urethane polymer bearing an aliphatic unsaturated hydrocarbyl group in its side chain, an organohydrogenpolysiloxane bearing a hydrosilyl group and a hydrosilylation catalyst. SOLUTION: The subject coating agent comprises 100 pts.wt. of a urethane polymer bearing at least one, in one molecule, aliphatic unsaturated hydrocarbyl group in a side chain, 0.1-100 pts.wt. of an organohydrogenpolysiloxane bearing at least two hydrosilyl groups in one molecule, 0.001-0.1 pt.wt. of a hydrosilylation catalyst such as chloroplatinic acid or the like and 1-150 pts.wt. of a polyfunctional isocyanate compound. The urethane polymer is obtained by reacting a linear polymer bearing amino or hydroxy groups on the both ends and an aliphatic unsaturated hydrocarbyl group in its side chain, such as a polysiloxane modified with an amino group at the both ends or the like, with a bifunctional isocyanate compound so that the molar ratio of the functional groups is at least 1.0, and has a weight-average mol.wt. of 10,000-500,000.</p> |
