Anodic oxidation method and production for titanium oxide coating and method of supporting catalyst

#The present invention relates to an anodic oxidation method, a titanium oxide film manufacturing method and a catalyst carrying method which is suitable, for example, for anodic oxidation of aluminum, titanium and catalyst carrying on the surface of alumite (registered trademark), capable of generating an oxide film at a low cost and rapidly by eliminating the use of a strongly acid or strongly basic electrolytic solution and using a carbonated water as an electrolytic solution, capable of improving the oxide film generating operation and rationalizing the water discharging treatment, capable of controlling the sealing treatment of oxide film through a simple method, capable of effecting the oxide film dyeing and catalyst carrying rationally and easily, applicable to an oxide film dyeing method and a catalyst manufacturing method, capable of effecting the catalyst carrying safely and surely without eroding a base material, accurately and efficiently, recollecting a catalyst material and a catalyst solution which have been subjected to the catalyst carrying and reutilizing thereof.

#An anodic oxidation method is known in which an oxide film having a predetermined thickness is artificially generated on a base surface of aluminum, for example. According to this method, an electrolytic solution having a strongly acid property such as sulfuric acid and oxalic acid is received in a treatment vessel, an aluminum-made object to be treated is received in this electrolytic solution, and an oxide film is formed on the base surface of the aluminum by oxidation reaction with the electrolytic solution serving the object as an anode (see, for example, Patent Document 1).

#However, this conventional oxide film generating method has such problems that an electrolytic solution having a strongly acid property such as sulfuric acid and oxalic acid is required, a special water discharging equipment is required for discharging the electrolytic solution, thus increasing the production cost and equipment cost, and operation is obliged to be conducted under such a circumstance that a toxic gas is generated.

#FIG. 1 is an explanatory view showing one embodiment of the present invention in which the present invention is applied to an anodic oxidation treatment of an aluminum product.

#FIG. 2 is an explanatory view showing a second embodiment of the present invention in which an electrolytic solution is generated at the outside of an treatment vessel, mixed with a sealing suppressing ion and then supplied to the treatment vessel.

#FIG. 3 is an explanatory view showing a third embodiment of the present invention in which a supercritical or subcritical carbon dioxide is introduced into a pressure resisting and hermetically closed treatment vessel and dissolved in water to generate an electrolytic solution, the resultant is mixed with a sealing suppressing ion and further added with a surface active agent so as to effect anodic oxidation treatment.

#The illustrated embodiment of the present invention will be described hereinafter, in which the present invention is applied to an anodic oxidation method of aluminum or its alloy as an object to be treated. In FIG. 1, reference numeral 1 denotes a stainless steel-made treatment vessel with a bottom. Lining of vinyl chloride or the like is applied to the inner surface of the treatment vessel 1. A cover member 2 is removably mounted on an upper opening part thereof.

#An aluminum-made object 3 to be treated as an object on which an anodic oxide film is generated and a cathode material 4 such as a lead plate are hung within the treatment vessel 1 through hooks 5, 6 such that they can be inserted in and removed from the vessel 1. An anode and a cathode of a power source apparatus are connected to them.

#Water 7 such as service water, pure water and the like as a material for generating an electrolytic solution is received in the treatment vessel 1, and a feed water pipe 9 communicated with a feed water source 8 is connected to its upper peripheral surface.