Patent ID: 8007698
Filing Date: 2011-08-30
Classification: B27N,B29C,B29K

Abstract:
1. A method for preparing a wood composite by steam injection pressing of a mixture of wood pieces and binder using phenol-formaldehyde resin as binder characterized in that (1) from 80 to 20 percent by weight of the phenol-formaldehyde resin is supplied as an aqueous composition prepared at a formaldehyde to phenol mole ratio (F:P) in the range of 2.15:1 to 2.65:1, the phenol-formaldehyde resin supplied as the aqueous composition having a weight average molecular weight in a range of 2000 to 8000; (2) from 20 to 80 percent by weight of the phenol-formaldehyde resin is supplied as particulate solids with a mole ratio of formaldehyde to phenol (F:P) in the phenol-formaldehyde resin particulate solids in the range of 2.1:1 to 2.6:1, the phenol-formaldehyde resin supplied as particulate solids having a weight average molecular weight in a range of 1500 to 4500 and (3) steam is injected into the mixture of wood pieces and binder during formation of the wood composite at a maximum pressure within a range of 15 to 95 psig.