GB1153801A - Improvements in or relating to the production of Wood-Wool and Packing or Insulating Material made therefrom - Google Patents

Abstract

1,153,801. Forms of wood. J. S. HOOD. 18 July, 1967 [9 Aug., 1966], No. 35556/66. Heading B5L. A method of producing a packing or insulating material comprises delivering curled-strand wood wool by fixed guide or stripper means on to an endless band travelling at the same linear spaced and adapted to maintain the original orientation of the strands which are cut 1À5 to 1À75 mm. wide and 0À275 to 0À374 mm. thick from timber of medium hardness having from 12 to 18 annular rings to the inch and seasoned to a moisture content not exceeding 18%. The timber is straight grained, fairly slow growth and has a density of 33 lb./cu. ft. and the strands are cut by a planing knife following scorer blades or a planing knife on the upper face of a comb. The strands form naturally into curls, Fig. 2, and are then compressed so as to interlock one with another without losing their lengthwise orientation. The wood wool may be pressed together using a cementing agent. The wood wool may be cut from pairs of billets by opposed combs and deposited on conveyer belts so as to be interlocked laterally 1, Fig. 5. The web is sprayed with a bonding agent and pressed by spiked rollers 3 into a converging means 5, the web then passing between a perforated plate 6 and a woven-wire conveyer belt 7 while the adhesive is cured or dried by hot air and finally oven dried at a temperature not exceeding 90‹ C. The web may have of the strands adhered between sheets of paper, plastics film or hessian. Alternatively, the exposed surfaces of the web are bonded to layers of polyurethane or flexible synthetic form. A cementitious slurry may be used to coat the web in the apparatus shown in Fig. 5, the web then being cut to length and compressed in moulds which may be pressure filled with foamed plastics material. The web may be coated with fire-insulating chemicals.