| 摘要 |
PROBLEM TO BE SOLVED: To provide a peelable aq. compsn. which, in environmentally friendly aq. system, can form a film showing good peeling property and has little temp. dependence with respect to peeling. SOLUTION: This aq. urethane resin is prepared first by reacting a dimer acid-based diol and a polyisocyanate to form a polyurethane prepolymer having NCOs on both ends, then a dimethylol alkane acid is reacted with the polyurethane prepolymer to form urethane bonds between NCOs and OHs, and an acidic urethane resin having a carboxylic acid content of 0.15-0.75 mg eq./g resin solids is formed, then the acidic urethane resin is neutralized with an amine volatile at room temp. and emulsified and dispersed by adding water. In this case, this peelable aq. compsn. contains the aq. urethane resin, of which 40-90 wt.% of resinous sold is the dimer acid diol, and a multi-valent metal compd. which forms a multi-valent metal ion in the aq. urethane resin, and the compounding quantity of the multi-valent metal compd. is 0.01-0.2 mol per 100 g resinous solid of the aq. urethane resin.
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