Abstract: A coating composition is disclosed consisting essentially of sodium silicate, magnesium oxide or magnesium hydroxide, titanium oxide and mica. Coatings from this composition are useful as electrically insulating coatings, particularly as applied to electrical steel sheets for magnetic cores, or to other metal products or substrates. The coating may be cured at temperatures within the range of 400.degree. to 500.degree. F. and provides reduced die wear of electrical steel sheet during punching operations. It also is tightly adherent and retains excellent electrical insulating properties after annealing at temperatures within the range of 1350.degree. to 1550.degree. F.

Abstract: A method of making a composition suitable for application to metal products for anti-scaling purposes or to produce legible markings on said products, said method comprising; providing first and second soluble alkali metal silicate solutions, preferably soluble sodium silicate solutions having silicate ratios of about 2.0 to 2.8 and 3.0 to 3.9, respectively. The two starting solutions are mixed to form a third solution. The cross-linking binder material is added to one of the solutions prior to addition of the other solid materials or to the combined silicate solutions. Finally, the other solids and water as needed are added to provide the above-mentioned composition. Utilizing the two diverse starting solutions provides a final mixture having a lower viscosity than when a single soluble silicate starting solution of equivalent SiO.sub.2 ratio is used.

Abstract: A composition is provided for use as an anti-scaling coating or to produce legible markings on metal products. The composition includes solids of from about 30 to 50 parts by weight of an opacifying pigment, from about 43 to 58 parts by weight of a water soluble alkali metal silicate binder, at least 50 percent of the alkali metal silicate being sodium silicate, the alkali metal silicate having a ratio of silicate to alkali metal oxide of from about 2.60 to 3.25, sufficient cross-linking binder to provide from about 1.5 to 5.0 parts B.sub.2 O.sub.3, the ratio of total pigment to total binder being within the range of 0.50 to 1.0, and sufficient water to give the composition a viscosity of about 800 to 5000 centipoise. The composition adheres when applied to metal products which are at temperatures of at least 250.degree. F. or which are subsequently heated to such temperatures so as to bake the coating.

Abstract: An improved coating for electrical or magnetic steel core-plates, having corrosion resistance comprises adding to a known combination of organic quaternary ammonium silicate and ethylene/acrylic or ethylene/vinyl acetate copolymer a small amount of a barium, strontium or lead chromate.

Abstract: An improved coating for electrical or magnetic steel core-plates, having corrosion resistance comprises adding to a known combination of organic quaternary ammonium silicate and ethylene/acrylic or ethylene/vinyl acetate copolymer a small amount of a barium, strontium or lead chromate.