| 摘要 |
PURPOSE:To obtain a compsn. which has excellent water resistance and film- forming properties and gives a coating film having excellent strength, by blending a modified polyvinyl alcohol contg. a silyl group, chitosan and an aldehyde compd. or a water-soluble metal salt. CONSTITUTION:A compsn. consists of a modified polyvinyl alcohol (A) contg. a silyl group, chitosan (B) having a viscosity (1% aq. soln. at 20 deg.C) of 70cP or below and at least one member (C) selected from among aldehyde compds. and water-soluble metal salts. Preferred examples of the modified polyvinyl alcohols contg. a silyl group are those in which the silyl group contains a reactive substituent such as alkoxyl or acyloxyl group or its salt. It is necessary that chitosan is one having a low degree of polymn. obtd. by a depolymerization treatment so as to give a viscosity (1% aq. soln. at 20 deg.C) of 70cP or below, pref. 1-30cP.
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