Intumescent coating composition and method of making combustible materials fire retardant

摘要

An intumescent coating composition comprises an aqueous dispersion of "intumescent solids", an aqueous film-forming latex of a polymer, and a solid plasticizer which has no action at ambient temperature but actively plasticizes the polymer above 75 DEG C. The "intumescent solids" are defined as consisting essentially of:-(1) a foam-forming substance consisting of mono- or diammonium phosphate, phosphoric acid, ammonium bromide, sulphate or sulphamate, sulphamic acid, or sodium tungstate or borate; (2) 10 to 70% by wt. of (1) of at least one non-resinous carbon yielding substance consisting of carbohydrates, modified starches, a polyhydric compound consisting of hexitols, pentitols or mono- and di-tetritols, or a water-dispersible protein, the amount of any starch being less than 15% of (1); and (3) 0 to 55% by wt. of (1) of glycine, urea, dimethyl urea, guanyl urea, guanidine or dicyandiamide. Film-forming polymers specified are polyvinyl chloride and vinyl chloride/vinyl ester, vinylidene chloride/acrylonitrile or vinyl chloride, and styrene/butadiene copolymers. Solid plasticizers specified are chlorinated paraffins, diphenyl phthalate, tris(p-tert-butylphenyl) phosphate, p-toluene sulphonamide and triphenyl phosphate. Optional ingredients mentioned are thickening agents such as methyl cellulose or sodium alginate; suspending agents such as gum tragacanth, gum arabic and Irish Moss; and fungicides such as sodium pentachlorophenolate, beta naphthol, copper fluoride, boric acid, borax, zinc salts, arsenates and arsenites. In examples titanium dioxide and N-methyl-N-oleyl taurine (wetting agent) are also used. The compositions may be applied to any combustible building material, such as fibre board, by roller, brush or spray application. Specifications 755,551 and 819,190 are referred to.ALSO:An intumescent coating composition comprises an aqueous dispersion of "intumescent solids", an aqueous film-forming latex of a polymer, and a solid plasticizer which has no action at ambient temperature but actively plasticizes the polymer above 75 DEG C. The "intumescent solids" are defined as consisting essentially of:- (1) a foam-forming substance consisting of mono- or di-ammonium phosphate, phosphoric acid, ammonium bromide, sulphate or sulphamate, sulphamic acid, or sodium tungstate or borate; (2) 10 to 70% by wt. of (1) of at least one non-resinous carbon yielding substance consisting of carbohydrates, modified starches, a polyhydric compound consisting of hexitols, pentitols or mono- and ditetritols, or a water-dispersible protein, the amount of any starch being less than 15% of (1); and (3) 0 to 55% by wt. of (1) of glycine, urea, dimethyl urea, guanyl urea, guanidine or dicyandiamide. Film-forming polymers specified are polyvinyl chloride and vinyl chloride/vinyl ester, vinylidene chloride/acrylonitrile or vinyl chloride, and styrene/butadiene copolymers. Solid plasticizers specified are chlorinated paraffins, e.g. C24H29Cl21, diphenyl phthalate, tris(p-tert-butylphenyl) phosphate, p-toluene sulphonamide and triphenyl phosphate. Optional ingredients mentioned are thickening agents such as methyl cellulose or sodium alginate; suspending agents such as gum tragacanth, gum arabic and Irish Moss; and fungicides such as sodium pentachlorophenolate, beta naphthol, copper fluoride, boric acid, borax, zinc salts, arsenates and arsenites. In examples titanium dioxide and N-methyl-N-oleyl taurine (wetting agent) are also used. The compositions may be applied to any combustible building material, such as fibre board, by roller, brush or spray application. Specifications 755,551 and 819,190 are referred to.