MELAMINE-FORMALDEHYDE POLYCONDENSATE

Condensation products obtainable by condensation of a mixture containing, as essential components, (A) from 90 to 99.9 mol % of a mixture essentially comprising (a) from 30 to 99 mol % of melamin and (b) from 1 to 70 mol % of a substitute melamin of the formula I in which X, X' and X'' are selected from the group consisting of -NH2, -NHR and -NRR', and X, X' and X'' are not simultaneously -NH2, and R and R' are selected from the group consisting of hydroxy-C2-C10-alkyl, hydroxy-C2-C4-alkyl-(oxa-C2-C4-alkyl)n where n = 1 to 5, and amino-C2-C12-alkyl, or mixtures of melamins I, and (B) from 0.1 to 10 mol %, based on (A) and (B), of phenols which are unsubstituted or substituted by radicals selected from the group consisting of C1-C9-alkyl and hydroxyl, or of C1-C4-alkanes which are substituted by two or three phenol groups, or di(hydroxyphenyl) sulphones, or mixtures of these phenols, with formaldehyde or formaldehyde-generating compounds, where the molar ratio between melamin and formaldehyde is in the range from 1:1.15 to 1:4.5.