Method for forming boards from particles

Claim 1

The method of producing a fiberboard comprising: a. mixing a dry, powdered, thermo-setting polymeric bonding agent homogeneously with a multiplicity of elongated cellulosic fibers having a directional grain and a long axis in the direction of said grain, said fibers having a moisture content from about 9 to 15 percent on a dry weight basis; b. depositing said mixture into a vertically oriented deckle box having said walls, an upper entrance and a lower exit, said mixture being deposited through said upper entrance to cause said mixture to fall vertically downwardly through said box toward said exit; c. establishing between a pair of opposing side walls within said box, at an intensity of from about 1500 to 3750 volts per inch a horizontally directed electrical field to cause the fibers descending within said box to become oriented with said long axis aligned with the direction of said field, said field having alternating polarity to prevent movement of said fibers toward said walls and separation of said fibers from said bonding agent; d. collecting said mixture of oriented fibers and bonding agent on an air pervious screen disposed beneath said exit of said deckle box, said screen having a partial vacuum therebeneath to form on said screen a mat of said fibers and bonding agent, said mat being retained in position by said partial vacuum; e. removing said mat from said screen; and, f. subjecting said mat to heat and pressure to consolidate said mat, activate said bonding agent, and bond said fibers into a fiberboard.

Claim 2

The method of producing a fiberboard comprising: a. mixing a dry, powdered, thermo-setting polymeric bonding agent homogeneously with a multiplicity of elongated cellulosic fibers having a directional grain and a long axis in the direction of said grain, said fibers having a moisture content from about 9 to 15 percent on a dry weight basis; b. depositing said mixture into a vertically oriented deckle box having said walls, an upper entrance and a lower exit, said mixture being deposited through said upper entrance to cause said mixture to fall vertically downwardly through said box toward said exit; c. establishing between a pair of opposing side walls within said box, at an intensity of from about 1500 to 3750 volts per inch a horizontally directed electrical field to cause the fibers descending within said box to become oriented with said long axis aligned with the direction of said field, said field having alternating polarity to prevent movement of said fibers toward said walls and separation of said fibers from said bonding agent; d. collecting said mixture of oriented fibers and bonding agent on an air pervious screen disposed beneath said exit of said deckle box, said screen having a partial vacuum therebeneath to form on said screen a mat of said fibers and bonding agent, said mat being retained in position by said partial vacuum; e. removing said mat from said screen; and, f. subjecting said mat to heat and pressure to consolidate said mat, activate said bonding agent, and bond said fibers into a fiberboard.