| 摘要 |
Woodworking materials having a lower subsequent formaldehyde emission can be prepared in an advantageous manner and with good resin reactivity and good strengths and swelling properties by mixing lignocellulose-containing particles, for example wood particles, with a curable binder based on curable aminoplast condensates and then pressing the mixture under the action of heat, a mixture A containing a water-compatible agent for binding formaldehyde being applied to or mixed with the particles before the latter are mixed with the curable binder, if the mixture A is an aqueous solution which has a pH of from 3.0 to 6.5 and contains (a) organic acids which attack wood only insignificantly, if at all, in an amount of more than 15% by weight, based on the solids content of the solution, preferably a mixture of aliphatic carboxylic acids of 4 to 10 carbon atoms, and (b) a formaldehyde-binding, nitrogen-containing compound, in particular urea.
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