Patent GB-1123773-A (GB)
Title: Refractory coating compositions
Inventor: POLLARD LEONARD WALTER
IPC: C01B33/14
Filed: 1966-01-31
Abstract: A coating composition comprises refractory solid particles suspended in an aqueous liquid containing a binder, the suspension being stabilized by dispersion therewith of 0.2-2.0% weight of Xanthomonas hydrophilic colloid. The binder is a silica-, aqua- or organosol or aqueous dispersion of aluminium phosphate, ethyl silicate, sodium silicate and mixtures thereof with the silica sol.  This binder may be used in the amount 30-90 weight per cent.  The solid particles (e.g. SiO2, insoluble metal silicates such as those of Mg, Al and Zr, siliceous clays, Al2O3 and graphite) have a particle size < 125 mesh (U.S. Standard Sieve Series).  The solid particles may be present in the amount of 10-70 weight per cent.  The silica sol preferably contains particles \sO 150 mm  having surface areas 20 m2/g., and has a concentration of 0.1-60% weight SiO2.  The composition may have a viscosity of 1500-4500 c.p.s. at 70 DEG  F.  Amines and polyhydroxy compounds, e.g. glycols, may be present to stabilize the silica sol. The composition may also contain alkali, carboxymethyl cellulose, alginates, ethyl cellulose, causticized acrylic acid and acrylamide. The coating composition can be applied to surfaces, e.g. metal stools and firebrick, having temperatures of 212-800 DEG  F. by spraying. The thickness of the coating is preferably 0.01-3 inches.ALSO:A coating composition comprises refractory solid particles suspended in an aqueous liquid containing a binder, the suspension being stabilized by dispersion therewith of 0.2-2.0% wt. of Xanthomonas hydrophilic colloid.  The binder is a silica aqua-or organosol or aqueous dispersion of aluminium phosphate, ethyl silicate, sodium silicate and mixtures thereof with the silica sol.  This binder may be used in the amount 30-90 wt.%.  The solid particles (e.g. SiO2, insoluble metal silicates such as those of Mg, Al and Zr, siliceous clays, Al2O3 and graphite) have a particle size <125 mesh (U.S. Standard Sieve Series).  The solid particles may be present in the amount 10-70 wt.%.  The silica sol preferably contains particles \sO 150 mm  having surface areas 20m2/g and has a concentration of 0.1-60% wt. SiO2.  The composition may have a viscosity of 1500-4500 cps. at 70 DEG  F.  Amines and polyhydroxy compounds, e.g. glycols, may be present to stabilize the silica sol.  The composition may also contain alkali, carboxymethyl cellulose, alginates, ethyl cellulose, causticized acrylic acid and acrylamide.ALSO:A coating composition comprises refractory solid particles suspended in an aqueous liquid containing a binder, the suspension being stabilised by dispersion therewith of 0.2-2.0% wt. of Xanthomonas hydrophillic colloid.  The binder is a silica aqua- or organo-sol or aqueous dispersion of aluminium phosphate, ethyl silicate, sodium silicate and mixtures thereof with the silica sol.  This binder may be used in the amount 30-90 wt.%  The solid particles (e.g. SiO2, insoluble metal silicates such as those of Mg, Al and Zr, siliceous clays, Al2O3 and graphite) have a particle size <125 mesh (U.S. Standard Sieve Series).  The solid particles may be present in the amount 10-70 wt.%.  The silica sol preferably contains particles not greater than 150 mm  having surface areas 20m2/g and has a concentration of 0.1-60% wt. SiO2. The composition may have a viscosity of 1500-4500 cps. at 70 DEG F. Amines and polyhydroxy compounds, e.g. glycols, may be present to stabilise the silica sol.  The composition may also contain alkali, carboxy-methyl cellulose, alginates, ethyl cellulose, causticised acrylic acid and acrylamide.  The coating composition can be applied to surfaces, e.g. metal stools and firebrick, having temps. of 212-800 DEG F by spraying.  The thickness of the coating is preferably 0.01-3 inch.