A treatment agent for chromium-free insulating coating formation suitable for forming an insulating coating on a surface of a grain-oriented electrical steel sheet. The treatment agent includes components (A), (B), (C), and (D). The component (B) is contained in an amount of 50 to 150 parts by mass on a SiO.sub.2 solid basis, and the component (C) is contained in an amount of 5.0 parts by mass or more on an elemental metal basis, the amounts being based on 100 parts by mass, on a solid basis, of the component (A). The component (D) is contained in an amount that a molar ratio of M.sup.2+ and M.sup.3+, each being a metal element in the treatment agent for chromium-free insulating coating formation, to a phosphorus element P satisfies a specified relationship, and the treatment agent for chromium-free insulating coating formation has a pH of less than 4.5.

The present invention provides a hearth roll for heat treatment furnaces, which has excellent build-up resistance, has a hexavalent-chromium-free thermal spray coating film formed on the roll surface thereof and is safe for the environment. A method for manufacturing a hearth roll for continuous annealing furnaces includes a first step of applying an aqueous solution containing chromium phosphate onto a thermal spray coating film formed on the roll surface of a hearth roll or impregnating the thermal spray coating film with the aqueous solution; and a second step of burning the hearth roll.

A pre-coating agent composition for a grain-oriednted electrical steel sheet, a grain-oriednted electrical steel sheet including the same, and a manufacturing method thereof are provided. Particularly, a pre-coating agent composition for a grain-oriednted electrical steel sheet including an acid containing boron (B); and a solvent, a grain-oriednted electrical steel sheet including the same, and a manufacturing method thereof are provided.

This grain-oriented electrical steel sheet includes a base steel sheet, a forsterite-based primary film disposed on a surface of the base steel sheet, and a phosphate-based tension-imparting film containing no chromium, which is disposed on a surface of the primary film. In a case where a Ti content and a S content are respectively expressed as XTi and XS, by mass %, the forsterite-based primary film satisfies Expression (1) and Expression (2). A strain-introduced magnetic domain control is performed on the grain-oriented electrical steel sheet.

0.10≤XTi/XS≤10.00   Expression (1)

XTi+XS≥0.10 mass %.   Expression (2)

[Problem] To provide: a coating liquid for forming an insulation coating for grain-oriented electrical steel sheets, which enables the achievement of excellent coating properties including high coating tension and excellent corrosion resistance even without using a chromium compound; a grain-oriented electrical steel sheet; and a method for producing a grain-oriented electrical steel sheet. [Solution] A coating liquid for forming an insulation coating for grain-oriented electrical steel sheets, which contains boric acid and hydrated silicate particles containing aluminum.

An embodiment of the present invention includes: an electrical steel sheet substrate; and an insulating coating on one or both surfaces of the electrical steel sheet substrate, wherein the insulating coating includes a silane compound and a metal hydroxide.

A material for gaskets is disclosed, wherein a metal surface coating layer, a primer layer and a rubber layer are formed, or a metal surface coating layer and a rubber layer are formed on at least a part of one side or both sides of a substrate formed of a metal plate sequentially from the metal plate side, and the metal surface coating layer comprises (A) one or more carbonates selected from the group consisting of Mg carbonate, Co carbonate, Zr carbonate, Mn carbonate, Ni carbonate, and Cu carbonate and (B) one or more selected from the group consisting of silica, alumina, zirconia, and titania.

Provided are coated metal, the metal having improved properties due to a novel coating, a coating-forming treatment solution for forming the novel coating, and a method for producing the coated metal that has the novel coating. The coated metal includes metal and a coating formed on the metal. The coating includes Si, P, and O, and at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al, and Mn. The coating includes a compound having a NASICON-type crystal structure represented by the general formula M.sup.IM.sup.IV.sub.2(M.sup.VO.sub.4).sub.3.

Provided are coated metal, the metal having improved properties due to a novel coating, a coating-forming treatment solution for forming the novel coating, and a method for producing the coated metal that has the novel coating. The coated metal includes metal and a coating formed on the metal. The coating includes Si, P, and O, and at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al, and Mn. The coating includes a compound having a NASICON-type crystal structure represented by the general formula M.sup.IM.sup.IV.sub.2(M.sup.VO.sub.4).sub.3.

An insulating coating for an electrical steel sheet is provided that is formed on a surface of a base metal of the electrical steel sheet and that contains a polyvalent metal phosphate of one or more elements selected from Al, Zn, Mg and Ca, and has an enriched layer of a divalent metal at an interface with the surface of the base metal. An enrichment of the divalent metal contained in the enriched layer is 0.01 g/m.sup.2 or more and less than 0.2 g/m.sup.2.