Coating

摘要

Coating material containing a condensation product A from a resin A1 with COOH groups and a resin A2 with OH groups, water soluble or water dispersible high molecular polyurethane B of number average mol. wt. Mn of at least 10 kg/mole and a weight average mol. wt. at least 20 kg/mole, and curing agent C first active at a temperature of at least 80 degrees C is new. A coating material containing a condensation product A from a resin A1 with COOH groups and a resin A2 with OH groups, water soluble or water dispersible high molecular polyurethane B of number average mol. wt. Mn of at least 10 kg/mole ( as measured by GPC, measured with a polystyrene standard) and a weight average mol. wt. at least 20 kg/mole, and curing agent C first active at a temperature of at least 80 degrees C is new. Independent claims are also included for the following; (1) a coating material for formulation of automobile filler paints containing a high molecular polyurethane B as above making at least 80% of the binder, and an aminoplastic curing agent C2; (2) a process for preparation of a coating agent by mixing A, B, and C; (3) a process for preparation of a coating agent by mixing A with a blocked isocyanate C, and addition of B and water dilutable aminoplastic C2 to the mixture; and (4) Polyurethane B which is obtained by reaction of polyisocyanate BA with polyols BB of Mn of at least 400 g/mole, optionally low molecular polyols BC and compounds BD, which has at least two groups reactive to isocyanates and at least one group capable of anionic binding, to give (sic) free NCO group containing prepolymer. This has a Staudinger number of at least 15 cm<3>/g, at least partial neutralization of the group in compound BD capable of anion formation, and formation of an anionic group, dispersion of this prepolymer group in water, and reaction of the neutralized prepolymer with at least one component selected from low molecular polyols BE, which has no further groups reactive to isocyanates. This compound is in excess, and compounds BF, which are monofunctional with respect to isocyanates or contain active hydrogen atoms of different reactivity and are different from compounds BE, and compounds BG, which are different from compounds BB, BC, BD, BE, and BF.