Abstract: A new metering and proportioning apparatus for directly applying a two-component adhesive in a wood laminating process is described. The key element of the invention is a valve system regulating flow of resin and hardener to and from double-acting cylinder pumps. The new system eliminates conventional spool valve difficulties. Each component cylinder pump is supplied with a pair of 3-way ball valves which are manifolded to direct component flows. A pneumatic control system senses completion of a component discharge stroke and causes simultaneous reversal of the ball valve pair for discharge of component and refilling of the emptied side of the cylinder on the return stroke. A two-level optical sensor detects a workpiece and opens extruder head discharge. The sensor operates a modulating valve in the resin supply line as the workpiece proceeds ensuring even spread rate.

Abstract: A glue foamable to high density comprises an aqueous alkaline thermosetting resin and a surfactant comprising (1) a fatty acid amide of the alkanol-amines or (2) a tertiary amine oxide used in amount sufficient to render the glue foamable to a stable foam having a density of at least 0.5 and a viscosity of from 1,000 to 20,000 centipoises upon being beaten with air. The glue is useful particularly in the manufacture of plywood.

Abstract: 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.

Abstract: A fast cured lignocellulosic particle board comprises a hot consolidated laminar mat of lignocellulosic particles. The mat has a middle lamina of particles coated with a fast setting, acid catalyzed, phenol aldehyde thermosetting resin, while the two surface laminae comprise particles coated with a relatively slow curing, alkali catalyzed phenol aldehyde thermosetting resin. The middle lamina is fast curing, but 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 nonadherent 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.

Abstract: A liquid adhesive composition for use in adhesive applicators of the curtain-coating class, such as are used in coating plywood veneers in the manufacture of plywood, comprises: An aqueous, alkaline phenol-aldehyde resinous adhesive, a filler, and a minor proportion of 2,4,7,9-tetramethyl-5-decyne-4,7-diol, or of the ethylene glycol-,propylene glycol-,and butylene glycol-ethers thereof having from 1 to 10 mols of glycol per mol of diol. The diol or diol ether serves the function of improving the curtain-forming qualities of the adhesive composition. In particular, its inclusion in the composition insures curtain uniformity, i.e. the absence of curtain breaks and tears, and uniform spread on the substrate.