Aqueous heat-cupable coating substance in a polyester and acrylic base, process for its manufacture and its use

Claim 1

Aqueous heat-curable coating substance in a base of polyester and acrylic resin mixed with amine resin and neutralizing agents, which may contain the usual paint additives, pigments, fillers and/or organic solvents, characterized by the fact that it contains as binding agents (A) 20-25%/weight (in relation to the solid matter content in the binding agent) of an amine resin cross-linking agent and (B) 80-55 %/weight (in relation to the solid matter content in the binding agent) of a polyester oligomer polyacrylate which is water soluble following neutralization with bases and whose numerical mean molecular weight (Mn) is 800 to 2000, manufactured by the radical polymerization of 80-50 %/weight minimum of (a) a hydroxyfunctional (meth)acrylic acid ester and (b) a monofunctional αβ-ethylenically unsaturated carbonic acid and (c) if required, an αβ-ethylenically unsaturated monomer with no functional groups in 20 to 50 %/weight of a hydroxyfunctional polyester oligomer, obtainable by the polycondensation of diols, polyols and dicarbonic acids and their derivatives, with a calculated molecular weight of 200 to 1000, a hydroxyl value of 280 to 600 and an acid value of 0 to 1.5, in which the monomers (a), (b) and (c) are used in such quantities that the resulting polyester oligomer polyacrylate has a hydroxyl value of 150 to 390 and an acid value of 16 to 40.