Abstract: A method of making a composite board comprising (a) applying a layer of a first composition comprising a thermosetting resin and a catalyst therefor to the surface of a mould; (b) allowing the thermosetting resin to polymerize; (c) applying a layer of a connecting composition comprising an adhesive or a second composition of thermosetting resin and catalyst to the layer (a); and (d) placing a structure comprising one or more laminae on the connecting composition, each lamina comprising first and second sheets of material fibre material and a corrugated sheet or a cellular core of natural fibre material sandwiched between the first and second sheets, the lamina being impregnated with thermosetting resin, extender and catalyst; the thermosetting resin being polymerized on the layer of step (c); (e) allowing the connecting composition to set and removing the composite board from the mould.

Abstract: A method of making a foamed building board or the like from the following components:(a) a major amount by weight of an inorganic base material selected from the group consisting of a calcium sulphate hemi-hydrate, magnesium oxychloride, magnesium oxysulphate and a hydraulic cement;(b) a suitable amount by weight of the inorganic base material of a thermosetting resin which is miscible, soluble or dispersable in water;(c) a suitable amount of a catalyst for the thermosetting resin;(d) water in an amount sufficient to rehydrate the inorganic base material with the water present in the other components;(e) a suitable amount of a plasticizer such as a melamine formaldehyde condensate;(f) a suitable amount of a polyvinyl alcohol;(g) a suitable amount of a retarder for the setting time of the inorganic base material;(h) a suitable amount of a fibrous reinforcing material; and(i) a suitable amount by weight of a foam or a foaming agent; which comprises the steps of:(1) mixing together components (a), (b), (c), (d),

Abstract: A composite panel comprises first and second sheets 20, 22 of a natural fibre material such as corrugated cardboard, each sheet 20, 22 having been impregnated with a liquid composition comprising a thermosetting resin, an extending liquid for the thermosetting resin and a catalyst for the thermosetting resin, the thermosetting resin having been polymerized, a cellular core 10 of a natural fibre material such as kraft paper, the cellular core 10 having been impregnated with a liquid composition comprising a thermosetting resin, an extending liquid for the thermosetting resin and a catalyst for the thermosetting resin, the thermosetting resin having been polymerized, the cellular core 10 being sandwiched between and adhered to the first and second sheets 20, 22; and a filler composition located in all of the cells of the core 10, the filler composition comprising a mixture of an inorganic insulating material and a material which releases water at elevated temperatures, in granular form.

Abstract: A method of making a composite structure from two first sheets of a natural fibre material such as paper and a second corrugated sheet of a natural fibre material such as paper, the second sheet being sandwiched between the two first sheets, includes the steps of impregnating the sheets with a liquid composition comprising a thermosetting resin such as a phenolic resin, an extending liquid for the thermosetting resin and a catalyst for the thermosetting resin, locating the second sheet between the two first sheets and polymerising the thermosetting resin to join the second sheet to the two first sheets to form the composite structure. The composite structure is of use in the building and packaging industry.

Abstract: There is provided a method of preparing a natural fibrous material particle composition such as a wood chip composition for use in forming a particle board which includes the steps of impregnating from 50 to 95% by weight of the composition of the particles with a compound selected from coal tar, pitch, asphalt and bitumen dissolved in a solvent therefor such as dichloromethane, applying from 2.5 to 25% by weight of the composition of a novolac resin including a cross-linking agent, in finely divided powder form, to the impregnated particles so that the resin adheres to the impregnated particles, and recovering the solvent. This composition may be used to manufacture a particle board in a platen press by coating the platens of the platen press with a layer of the novolac resin, and then placing the composition between the platnes and subjecting the composition to suitable conditions of temperature and pressure to cause the novolac resin to cross-link to form the board.