Heat hardening mixtures

Claim 1

A heat-hardenable dispersion of a finely divided solid resin in liquid etherified methylolaminotriazine in which liquid the degree of methylolation averages at least about 50 percent, the degrees of etherification of the methylol groups averages at least about 70%, and about 20 to 80 mol percent of the etherifying groups are alkyl groups with up to 2 carbon atoms, the remaining etherifying groups being alkoxyethyl groups having alkoxy moieties with up to 4 carbon atoms; the resin being an uncured mixture of about 30 to about 45% by weight of a polyester condensate with an average molecular weight about 500 to about 6000, an acid number below about 20, an OH number about 400 to about 800 and a softening temperature about 80° to about 150°C, the balance of the resin being essentially a polyurethane-forming polyisocyanate at least about half of whose isocyanate groups are masked with a lactam-masking agent that unmasks on heating to curing temperature; the polyester condensate being essentially the polyester of (a) a mixture of isophthalic and terephthalic acids in which about 10 to about 90 mol percent is isophthalic acid, and (b) at least one saturated aliphatic polyol having 4 to 6 OH groups; and the resin being present in an amount from about 20 to about 500% by weight of the liquid.