| 摘要 |
PCT No. PCT/EP89/01126 Sec. 371 Date May 3, 1991 Sec. 102(e) Date May 3, 1991 PCT Filed Sep. 26, 1989 PCT Pub. No. WO90/03851 PCT Pub. Date Apr. 19, 1990.The invention relates to a process for the preparation of a multicoat coating which uses an aqueous, clear topcoat composition containing a polyacrylate resin as binder. The polyacrylate resin can be obtained by adding an ethylenically unsaturated monomer (a1) which contains carboxyl groups, and a mixture (b) consisting of (meth)acrylic esters which are free from carboxyl groups and of ethylenically unsaturated monomers which contain hydroxyl groups, to an organic solvent or mixture of solvents either successively or alternately in part amounts and polymerizing the mixture in the presence of a radical-forming initiator, neutralizing the resultant polyacrylate resin after termination of the polymerization and dispersing it in water. The type and amount of (a1) and (b) are chosen such that the polyacrylate resin has a hydroxyl value of 40 to 200, an acid value of 20 to 100 and a glass transition temperature (TG) of -40 DEG C. to 60 DEG C.
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