Aqueous coating compositions containing a mercaptan polyester and an aminoplast

摘要

Curable compositions, suitable for use as surface coatings, comprise (I) 100 PARTS BY WEIGHT, CALCULATED ON ITS RESIN-FORMING SOLIDS CONTENT, OF AN AMMONIUM OR AMINE SALT OF A CARBOXYL-CONTAINING POLYESTER WHICH CONTAINS, ON AVERAGE, AT LEAST TWO MERCAPTAN GROUPS DIRECTLY ATTACHED TO ALIPHATIC CARBON ATOMS PER MOLECULE AND AT LEAST ONE ALIPHATIC GROUP OF 8 OR MORE CARBON ATOMS, (II) FROM 5 TO 100 PARTS BY WEIGHT, CALCULATED ON ITS RESIN-FORMING SOLIDS CONTENT, OF A WATER-SOLUBLE AMINOPLAST CONTAINING, PER AVERAGE MOLECULE, DIRECTLY ATTACHED TO AN AMIDO NITROGEN ATOM OR ATOMS OF UREA OR OF A POLYAMINO-1,3,5-TRIAZINE, AT LEAST TWO GROUPS OF FORMULA -CH2OR, where R denotes a hydrogen atom or a methyl or ethyl group, and (III) WATER.