A grain-oriented electrical steel sheet includes: a base steel sheet; an intermediate layer arranged in contact with the base steel sheet; and an insulation coating arranged in contact with the intermediate layer to be an outermost surface, in which a Cr content of the insulation coating is 0.1 at % or more on average, and when viewing a cross section whose cutting direction is parallel to a thickness direction, the insulation coating has a compound layer containing a crystalline phosphide in an area in contact with the intermediate layer.

A grain-oriented electrical steel sheet includes: a base steel sheet; an intermediate layer arranged in contact with the base steel sheet; and an insulation coating arranged in contact with the intermediate layer to be an outermost surface, in which a Cr content of the insulation coating is 0.1 at % or more on average, and when viewing a cross section whose cutting direction is parallel to a thickness direction, the insulation coating has a compound layer containing a crystalline phosphide in an area in contact with the intermediate layer.

Provided is a method of forming an apatite coating, including brining an apatite-forming precursor solution including Ca.sup.2+ ions and PO.sub.4.sup.3 ions into direct contact with at least one region of the substrate, emitting a laser beam onto the region of the substrate in direct contact with the precursor solution through the precursor solution, and forming apatite on the region onto which the laser beam is emitted.

Provided is a method of forming an apatite coating, including brining an apatite-forming precursor solution including Ca.sup.2+ ions and PO.sub.4.sup.3 ions into direct contact with at least one region of the substrate, emitting a laser beam onto the region of the substrate in direct contact with the precursor solution through the precursor solution, and forming apatite on the region onto which the laser beam is emitted.

Provided is a coated aluminum material for joining having an adhesion layer on a surface, and can exert excellent adhesion strength and corrosion resistance performance even under severe use conditions while being chromium-free. Provided is a coated aluminum material capable of producing the coated aluminum material for joining, and an aluminum resin composite material using the coated aluminum material for joining. Disclosed are a coated aluminum material for joining having an adhesion layer on a surface thereof and including a coated aluminum material and a silica-containing film formed on a surface of the aluminum material, the silica-containing film including 0.5 to 35 mass % of a silane coupling agent and having Si and P contents of 2 to 60, and 0.1 to 6.0 mg/m.sup.2, respectively, and P/Si mass ratio of P content and Si content of 0.02 to 0.15, and a coated aluminum material capable of producing the coated aluminum material for joining, and an aluminum resin composite material obtained using the coated aluminum material for joining.

A liquid composition comprising at least one bisphosphonic compound bearing at least one partially fluorinated, perfluorinated (PF) or perfluorpolether (PFPE) group. The bisphosphonic compound is dissolved in at least one non-flammable fluorinated solvent or in a mixture of non-flammable fluorinated solvents. A method for increasing the lipophobic or hydrophobic properties of a surface is also disclosed, wherein a liquid composition comprising at least one bisphosphonic compound bearing at least one partially fluorinated, perfluorinated (PF) or perfluorpolether (PFPE) group is applied to the surface. The method may include preliminary oxidation of the surface, if necessary; contacting the surface with the liquid composition until the bisphosphonic compound contained therein is assembled in a layer coating the surface; and drying the surface thus coated.

A liquid composition comprising at least one bisphosphonic compound bearing at least one partially fluorinated, perfluorinated (PF) or perfluorpolether (PFPE) group. The bisphosphonic compound is dissolved in at least one non-flammable fluorinated solvent or in a mixture of non-flammable fluorinated solvents. A method for increasing the lipophobic or hydrophobic properties of a surface is also disclosed, wherein a liquid composition comprising at least one bisphosphonic compound bearing at least one partially fluorinated, perfluorinated (PF) or perfluorpolether (PFPE) group is applied to the surface. The method may include preliminary oxidation of the surface, if necessary; contacting the surface with the liquid composition until the bisphosphonic compound contained therein is assembled in a layer coating the surface; and drying the surface thus coated.

A non-oriented electrical steel sheet according to an embodiment of the present invention is a non-oriented electrical steel sheet including a base metal steel sheet and a composite coating film that is formed on surfaces of the base metal steel sheet and includes Zn-containing phosphate and an organic resin, wherein the non-oriented electrical steel sheet contains crystalline aluminum phosphate showing diffraction lines belonging to ICDD No. 01-074-3256 when the composite coating film is measured by a wide-angle X-ray diffraction method.

A non-oriented electrical steel sheet according to an embodiment of the present invention is a non-oriented electrical steel sheet including a base metal steel sheet and a composite coating film that is formed on surfaces of the base metal steel sheet and includes Zn-containing phosphate and an organic resin, wherein the non-oriented electrical steel sheet contains crystalline aluminum phosphate showing diffraction lines belonging to ICDD No. 01-074-3256 when the composite coating film is measured by a wide-angle X-ray diffraction method.

A steel sheet with excellent phosphatability, according to one embodiment of the present invention, comprises, by wt %, 0.02-0.06% of carbon (C), 0.01% or less of silicon (Si) (excluding 0%), 0.1-0.24% of manganese (Mn), 0.02% or less of aluminum (Al) (excluding 0%), 0.015-0.04% of phosphorus (P), and the balance of iron (Fe) and inevitable impurities, and has an oxide layer having a thickness of 10 nm or less inward from the surface of the steel sheet, and satisfies the following formula 1.

([Mn]+[Si]+[Al])/(3[P])0.6 [Formula 1]

(In formula 1, [Mn], [Si], [Al] and [P] mean the maximum amount of each element when elemental analysis is carried out in the thickness direction of the oxide layer.)