Importance

Loading Importance Indicators...

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 1:1.2 to 1:5 and the molar ratio of melamine to urea ranges from 1:0.1 to 1:2.8. Also disclosed is the use of these resins to produce post-forming laminates.

Loading the Abstract Image...

First Claim