摘要 |
A fast cured lignocellulosic particle board is made by forming a middle lamina of particles coated with from 3 to 15% by weight, dry solids basis, of an acid catalyzed phenol aldehyde thermosetting resin having a pH of less than 2, and opposed surface laminae of particles coated with from 3 to 15% by weight, dry solids basis, of an alkali catalyzed phenol aldehyde thermosetting resin having an alkaline pH of not more than about 13. The middle lamina cures faster than the surface laminae, but is potentially adherent to the metal cauls of the hot press in which the board is manufactured. Although the surface laminae are slower curing, they are non-adherent to the cauls. The net result is a non-sticking particle board curable in the press in about one-half the press time conventionally required.
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