Patent ID: 6921431

Claim:
A thermal protective coating, comprising: in dry admixture, a. from about 5% to about 35% of colloidal silica, colloidal alumina, or combinations thereof; b. from about 23% to about 79% of a filler taken from the group consisting of silicon dioxide, aluminum oxide, titanium dioxide, magnesium oxide, calcium oxide, and boron oxide; c. from about 2% to about 20% of one or more emissivity agents taken from the group consisting of silicon hexaboride, boron carbide, silicon tetraboride, silicon carbide, molybdenum disilicide, tungsten disilicide, zirconium diboride, cupric chromite, and metallic oxides; and d. from about 1.5% to about 5.0% of a stabilizer taken from the group consisting of bentonite, kaolin, magnesium alumina silica clay, tabular alumina, and stabilized zirconium oxide.