Abstract: Modified melamine-formaldehyde resins are made of a condensate of formaldehyde, urea, melamine and modifying agents which contains: (a) a combination of 5 to 25 wt %, with respect to melamine, of dicyanodiamide and 8 to 30 wt %, with respect to melamine, of water-soluble polyalcohol with at least two hydroxyalkyl groups, and/or (b) 1.5 to 20 wt % amines having the formulas (Ia)NR.sub.4 R.sub.5 --R.sub.1 --X (Ia)and/or (Ib),NR.sub.4 R.sub.5 --R.sub.2 --Y--R.sub.3 --X (Ib)in which R.sub.1 and R.sub.3 are the same or different and depending on the meaning of X stand for a linear, branched or cyclic C.sub.1 -C.sub.12 alkyl or alkylene radical and R.sub.2 stands for a linear, branched or cyclic C.sub.1 -C.sub.12 alkylene radical; R.sub.4 and R.sub.5 can be the same or different and can stand for H or for a linear or branched C.sub.1 -C.sub.12 alkyl radical; and X can stand for hydrogen, OH or NR.sub.4 R.sub.5 and Y can stand for --O-- or --NH--. The molar ratio of melamine to formaldehyde ranges from 1:1.

Abstract: A melamine preparation consisting of 80 to 99.9% by weight of melamine having an average particle size of 0.01 to 0.1 mm and 0.1 to 20% by weight of urea, thiourea, biuret or urea or thiourea substituted by lower alkyl groups and a stable dispersion in polyether polyols prepared therefrom, which is used for the preparation of flame-resistant polyurethane foams.

Abstract: An improved process for substantially increasing the shelf-life of aqueous solutions of melamine-formaldehyde resins wherein the molar ratio of melamine to formaldehyde is from 1:1.7 to 1:3.5 by the addition of a stabilizing amount of urea after condensation, which process includes the steps of adjusting pH of the resin solution before and after the dissolution of the urea within certain narrow but easily controllable pH ranges. The properties of the resin solution can be further improved and the stabilizing effect of the addition of urea increased by adding a monohydric C.sub.1 -C.sub.4 alkanol during condensation of the resin.

Abstract: Modified aminoplast resins based on melamine and formaldehyde or urea and formaldehyde, which contain, as modifiers, methylolmelamines having a molar ratio of melamine to formaldehyde of 1:3 to 1:6, which are etherified with mono-alcohols having 1 to 4 carbon atoms, in a ratio of melamine to alcohol of 1:2 to 1:6. These resins are used, in particular, for the production of decorative, glossy-surface laminations.