Inorganic coating compositions with alkali silicate

Claim 1

A method for making an inorganic film-coated article comprising the steps of (a) coating a substrate with a viscous aqueous multicomponent suspension prepared by heating an aqueous suspension comprising 10-50 weight percent alkali silicate and 5-300 weight percent, based on the solids content of said alkali silicate solution, of amorphous silica powder of 0.5-50 micron particle size to above 50° C. with stirring, and (b) hardening the resulting coating by contact with an aqueous solution comprising a surface tension reducing agent selected from the group consisting of fluorcarbon sulfonic acid of the formula C n F 2n +1 SO 3 H wherein n is 1 to 16 and silicone compounds or their colloidal suspension of the formula ##EQU1## where R is methyl or phenyl and m is zero to 2230; and at least one member selected from the group consisting of phosphoric acid, ammonium phosphate, metal primary phosphate, ammonium chloride, metal chloride, ammonium sulfate, ammonium nitrate, metal nitrate, fluorosilicate, and ammonium persulfate, wherein the metal of said metal chloride is a transition metal or a member of Group II, III or IV of the Periodic Table; wherein the metal of said metal nitrate is a transition metal or a member of Group II, III or IV of the Periodic Table; and wherein said fluorosilicate is a metal hexafluorosilicate and said metal is a member of the group of lead, zinc, calcium, sodium and potassium.

Claim 2

A method for making an inorganic film-coated article comprising the steps of (a) coating a substrate with a viscous aqueous multicomponent suspension prepared by heating an aqueous suspension comprising 10-50 weight percent alkali silicate and 5-300 weight percent, based on the solids content of said alkali silicate solution, of amorphous silica powder of 0.5-50 micron particle size to above 50° C. with stirring, and (b) hardening the resulting coating by contact with an aqueous solution comprising a surface tension reducing agent selected from the group consisting of fluorcarbon sulfonic acid of the formula C n F 2n +1 SO 3 H wherein n is 1 to 16 and silicone compounds or their colloidal suspension of the formula ##EQU1## where R is methyl or phenyl and m is zero to 2230; and at least one member selected from the group consisting of phosphoric acid, ammonium phosphate, metal primary phosphate, ammonium chloride, metal chloride, ammonium sulfate, ammonium nitrate, metal nitrate, fluorosilicate, and ammonium persulfate, wherein the metal of said metal chloride is a transition metal or a member of Group II, III or IV of the Periodic Table; wherein the metal of said metal nitrate is a transition metal or a member of Group II, III or IV of the Periodic Table; and wherein said fluorosilicate is a metal hexafluorosilicate and said metal is a member of the group of lead, zinc, calcium, sodium and potassium.