PREPARATION OF LIGHTWEIGHT MDF

摘要

PURPOSE:To fill the interstices of fibers and to especially enhance the paintability of the surface at the cut end by a method wherein wax is added to fibers obtained by beating wood chips and foamable microcapsules are further mixed and emulsified with a thermosetting resin to form an emulsion which is, in turn, applied to the fibers as an adhesive to form the coated fibers into a mat having a predetermined wt. and this mat is pressed under heating to be formed into a plate. CONSTITUTION:Wax is added to beaten fibers in a wt. ratio of 0.5-3.0% and, separately, 10-25wt.% of a for,able capsule-shaped vinylidene chloride resin having a particle size of 20mum or less is mixed with a urea resin adhesive to be sufficiently emulsified therewith and the resulting emulsion is applied to the fibers in an amount of 10-20% by wt. of the fibers. The coated fibers are formed into a mat which is, in turn, pressed at hot plate temp. of 200 deg.C under pressure of 160kg/cm2 to be formed into a lightweight MDF. This lightweight MDF becomes well in the paintability at the cut end and enhanced in internal release strength and physical properties and, especially, high dimensional stability is obtained as a humidity-resistant and water-resistant material.