Abstract: A method for coating a metal substrate in which a coating film is applied reliably and strongly on a surface processed film on a metal matrix material. The coating method for the metal substrate includes an immersion step of immersing a surface-processed metal substrate in a solution mainly composed of an amorphous-like fluorine resin, a polymerization step of polymerizing the amorphous-like fluorine resin and the surface processed metal substrate, and a step of forming a coating film on a surface-processed surface of the metal substrate.

Abstract: A process for surface-treating a body made of metal is disclosed, which includes a step of immersing the body made of metal in an aqueous solution containing at least one organometallic compound and at least one film-forming assistant, thereby forming a transparent film on a surface of the body made of metal. Further, in accordance with the present invention, there is provided a composition of matter including a substrate made of magnesium or a magnesium alloy and a transparent film formed on the substrate, which can be prepared by the process.

Abstract: A process for surface-treating a body made of metal is disclosed, which includes a step of immersing the body made of metal in an aqueous solution containing at least one organometallic compound and at least one film-forming assistant, thereby forming a transparent film on a surface of the body made of metal. Further, in accordance with the present invention, there is provided a composition of matter including a substrate made of magnesium or a magnesium alloy and a transparent film formed on the substrate, which can be prepared by the process.

Abstract: A process for surface-treating a body made of metal is disclosed, which includes a step of immersing the body made of metal in an aqueous solution containing at least one organometallic compound and at least one film-forming assistant, thereby forming a transparent film on a surface of the body made of metal. Further, in accordance with the present invention, there is provided a composition of matter including a substrate made of magnesium or a magnesium alloy and a transparent film formed on the substrate, which can be prepared by the process.

Abstract: A method for surface-treating a substrate made of a magnesium-based metal material is disclosed, which includes immersing the substrate in an electrolyte composed of an aqueous solution containing at least one component selected from the group consisting of hydroxides, carbonates and bicarbonates of alkali metals or alkali earth metals, and a film-forming stabilizer, and conducting an electrolysis to form an anodic oxide film on a surface of the substrate. The film-forming stabilizer includes one component selected from salts of mineral acids, fluorides, silicates and silicofluorides and an additional component selected from ethylene glycol, trihydroxypropane, dihydroxyethyl ether and sodium hydroxybenzoate. Further, in accordance with the present invention, there is provided the substrate which is surface-treated by the method.