摘要 |
The present invention relates to a process for the production of wood-base materials which have at least one thin veneer layer adhesively bonded over the surface to a substrate or to further veneer layers, which process comprises the following steps: i. impregnation of a veneer with an aqueous curable composition which comprises a) at least one curable urea compound selected from urea compounds H which have at least one N-bonded group of the formula CH<SUB>2</SUB>OR, where R is hydrogen or C<SUB>1</SUB>-C<SUB>4</SUB>-alkyl, and/or a 1,2-bishydroxyethane-1,2-diyl group bridging the two nitrogen atoms of the urea, precondensates of the urea compound H, and reaction products or mixtures of the urea compound H with at least one alcohol which is selected from C<SUB>1</SUB>-C<SUB>6</SUB>-alkanols, C<SUB>2</SUB>-C<SUB>6</SUB>-polyols and oligoethylene glycols, and b) at least one catalyst K effecting crosslinking of the urea compound; ii) gluing of the impregnated veneer and/or the substrate with a glue composition and iii) processing of the glued veneer to give a wood-base material at elevated temperature with curing of the crosslinkable urea compound, the impregnated veneer comprising the crosslinkable urea compound in substantially uncrosslinked form before the gluing in step ii).
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