| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing an aqueous emulsion, having good film-making properties at a low temperature and leaving a small amount of tack on the resin coating surfaces. SOLUTION: This method polymerizes (A) an ethylenic unsaturated compound which gives the polymer having a Tg value of -30 deg.C or lower and (B) an ethylenic unsaturated compound which gives the polymer having a Tg value of -30 deg.C or higher by the power feed polymerization in an aqueous solvent, under the conditions that the total component A is divided into A1 and A2, A1 being first polymerized and then A2 being charged to the system to be polymerized; the component B is added to the component A2 when the latter is charged, to continue the polymerization process; and the following wt. ratios shall be satisfied, A1+A2+B=100, 20<=A1<=60, 10<=A2<=40 and 10<=B<=40, to have the whole copolymer of the components A and B having a Tg value of -35 to -15 deg.C.
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