| 摘要 |
PURPOSE:To provide a release agent which forms a coating film having a desirable balance among friction, release against an adherent and adhesion properties and which comprises an acrylic polymer, two particular types of polysiloxanes, a polyfunctional isocyanate compd. and a reaction catalyst. CONSTITUTION:An acrylic polymer (A) having a viscosity of 500-500,000 cP at 25 deg.C and containing at least two hydroxyl groups in its molecule is prepd. by copolymerizing an unsatd. monomer of the formula (wherein R1 is H or CH3; and R2 is a 1-18 C alkyl) with an unsatd. monomer having a hydroxyl group in the presence of a polymn. regulator. 100pts.wt. component (A) is mixed with 0.1-50pts.wt. straight-chainpolydiorganosiloxane (B) having a degree of polymerization of 2-2,000 and contg. a methyl group in an amt. of 0-80mol%, an org. group selected from among 2-20 C alkyl, cycloalkyl, aryl and aralkyl groups bonded to Si and at least two hydroxyl groups per molecule, 0-25pts.wt. polydimethylsiloxane (C) having a degree of polymerization of 10-20,000 and contg. at least two hydroxyl groups in this molecule, an isocyanate compd. (D) having an NCO group in an amt. of 0.2-5 equivalents relative to the hydroxyl groups of components (A) to (C), and a reaction catalyst (E).
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