Article coated with photocatalyst film, method for preparing the article and sputtering target for use in coating the film

Abstract

This invention relates to an article having a substrate with a photocatalyst coating film formed thereon by ae sputtering method, characterized in that the photocatalyst coating film comprises titanium oxide as a main component and at least one kind of metal having a sputtering rate for Ar being 0.9 to 2.7 times that of Ti, preferably at least one kind of metal selected from the group consisting of Fe, V, Mo, Nb, Al and Cr, in an amount of 0.01 to 10 wt % in terms of the sum of such metals. The coating film is formed by a method using a Ti metal sputtering target or a Ti sub-oxide sputtering target containing the metal in an amount of 0.01 to 10 wt % in terms of the sum of such metals, or a method using two kinds of targets for two sputtering cathodes and applying reversing potential so as to have a cathode and an anode alternately.

What is claimed is:  
     
         1 . An article having a substrate and a photocatalyst coating film formed thereon by a sputtering method, characterized in that the photocatalyst coating film comprises: 
 1) titanium oxide as a main component and 2) at least one kind of metal having a sputtering rate for Ar, which has at least one kind of energy in a 100 eV to 2000 eV ion energy area, being 0.9 to 2.7 times that of Ti.    
     
     
         2 . An article with the photocatalyst film coated thereon according to  claim 1 , wherein said sputtering rate of said metal is 9 to 2.3 times that of Ti.  
     
     
         3 . An article with the photocatalyst film coated thereon according to  claim 1 , wherein the metal is at least one metal selected from the group consisting of Fe, V, Mo, Nb, Al and Cr.  
     
     
         4 . An article with the photocatalyst film coated thereon according to  claim 1 , wherein the metal is at least one metal selected from the group consisting of Fe, V, Mo and Nb.  
     
     
         5 . An article with the photocatalyst film coated thereon according to  claim 1 , wherein the metal is at least one metal selected from the group consisting of Fe, V and Mo.  
     
     
         6 . An article with the photocatalyst film coated thereon according to one of claims  1 ˜ 5 , wherein the content of the metal is 0.01˜10 wt % in terms of such metals.  
     
     
         7 . A Ti metal sputtering target containing at least one metal selected from the group of metals described in one of claims  1 ˜ 6  in an amount of 0.01˜10 wt % in terms of the sum of such metals  
     
     
         8 . A Ti sub-oxide sputtering article containing at least one metal selected from the group of metals described in one of claims  1 ˜ 6  in an amount of 0.01 to 10 wt % in terms of the sum of such metals.  
     
     
         9 . A method for preparing a photocatalyst film coated article, characterized in that the article is prepared by a reactive sputtering method using oxygen gas and at least a sputtering target described in  claim 7  in a method for coating a substrate with a photocatalyst film comprising titanium oxide as a main component and at least one kind of metal having a sputtering rate for Ar, which has at least one kind of energy in a 100 to 2000 eV ion energy area, being 0.9 to 2.7 times that of Ti.  
     
     
         10 . A method for preparing a photocatalyst film coated article, characterized in that the article is prepared by a sputtering method using at least a sputtering target described in  claim 8  in a method for coating a substrate with a photocatalyst film comprising titanium oxide as a main component and at least one kind of metal having a sputtering rate for Ar, which has at least one kind of energy in a 100 eV to 2000 eV ion energy area, being 0.9 to 2.7 times that of Ti.  
     
     
         11 . A method for preparing a photocatalyst film coated article, characterized in that two cathodes respectively having a sputtering target of a metal or a metal oxide comprising the photocatalyst film attached adjoining each other, voltage is applied to reverse the polarity of two cathodes alternately so that when one cathode is the negative pole, the other cathode is the positive pole while when said the other cathode is the negative pole, said one cathode is the positive pole, and the two targets are sputtered simultaneously by a glow discharging plasma caused therefrom in a method for coating a substrate by a photocatalyst film comprising titanium oxide as a main component and at least one kind of metal having a sputtering rate for Ar, which has at least one kind of energy in a 100 eV to 2000 eV ion energy area, being 0.9 to 2.7 times that of Ti.  
     
     
         12 . An article coated with a photocatalyst film characterized in that it is prepared by the method described in one of claims  9  through  11 .