VERFAHREN ZUR HERSTELLUNG VON BINDEMITTELN FUR WASSERVERDUNNBARE, SAUREHARTENDE LACKE

摘要

Binders for water-thinnable, acid-curing coatings are prepared. These binders are obtained on mixing or partially cocondensing 45 - 90 % by weight of a low molecular weight, partially etherified, water-soluble urea-formaldehyde condensate, wherein the etherification alcohols are at least 50 % monoalcohols of 1 to 3 carbon atoms and 0 - 50 % monoalcohols of more than 3 carbon atoms and/or diols and/or diol monoalkyl ethers, with 10 - 55 % by weight of an oil-free saturated polyester having a hydroxyl number from 250 to 400 and containing from 10 to 25 % by weight of a polyethylene glycol having an average molecular weight between 300 and 1000, preferably 300 - 750. Conditions are atmospheric pressure and temperatures between 30 DEG C and reflux temperatures. The binders obtained can be used for any kind of coating for wood.