GB1097771A - Composite sheet building material - Google Patents

Abstract

A composite sheet building material embodies a layer or layers of fibrous material impregnated and coated with a mixture of solid epoxy resin with a melting point between 50 and 70 DEG C and an epoxidised pitch or tar, and a hardener or accelerator, with or without a plasticiser, the mixture being dissolved or dispersed in a low-boiling solvent in which all the constituent materials of the mixture are soluble or dispersable, the composite material being dried by evaporation of the solvent at a temperature not exceeding 60 DEG C leaving the mixture in the unreacted but heat-sensitive state. The material may be passed between rollers after the impregnation but before drying; the rollers may emboss the material to give it a broken level surface furnished with open-ended passages or channels forming a regular pattern enabling overlapped sheets to lie in close continuous contact. The impregnated and embossed sheet may be layered between two plain sheets of fibrous material which have been similarly impregnated, from all of which sheets the solvents are then evaporated, the open-ended passages or channels being retained. The fibrous material may be a felted paper, asbestos or mixtures of sulphite pulp. Bonding of the composite sheet material to itself where overlaid or to suitably prepared surfaces is accomplished by the application of heat thereto, e.g. from the application of molten bitumen or mastic asphalt or other hot bituminous material, or a heated roller. The material may be applied to a roof of concrete, or concrete with insulation, and the roof normally finished with a sand/cement screed, which may be treated with a bituminous primer and then coated with hot bitumen into which the material is rolled. The screed may be coated in strips, to present alternate strips of coated and uncoated concrete, with a synthetic resin, synthetic resin-bitumen mixture, or natural or residual bitumen with or without addition of natural resins or gums, as adhesives.ALSO:A composite sheet building material embodies a layer or layers of fibrous material impregnated and coated with a mixture of solid epoxy resin with a melting point between 50 and 70 DEG C, and an epoxidised pitch or tar, and a hardener or accelerator, with or without a plasticiser, the mixture being dissolved or dispersed in a low-boiling solvent in which all the constituent materials of the mixture are soluble or dispersable, the composite material being dried by evaporation of the solvent at a temperature not exceeding 60 DEG C leaving the mixture in the unreacted but heat-sensitive state. The material may be passed between rollers after the impregnation but before drying; the rollers may emboss the material to give it a broken level surface furnished with open-ended passages or channels forming a regular pattern enabling overlapped sheets to lie in close continuous contact. The impregnated and embossed sheet may be layered between two plain sheets of fibrous material which have been similarly impregnated, from all of which sheets the solvents are then evaporated, the open-ended passages or channels being retained. The fibrous material may be a felted paper, asbestos or mixtures of sulphite pulp. Bonding of the composite sheet material to itself where overlaid or to suitably prepared surfaces is accomplished by the application of heat thereto, e.g. from the application of molten bitumen or mastic asphalt or other hot bituminous material, or a heated roller. The material may be applied to a roof of concrete, or concrete with insulation, and the roof normally finished with a sand/cement screed, which may be treated with a bituminous primer and then coated with hot bitumen into which the material is rolled. The screed may be coated in strips, to present alternate strips of coated and uncoated concrete, with a synthetic resin, synthetic resin-bitumen mixture, or natural or residual bitumen with or without addition of natural resins or gums, as adhesive.