Anodizing device, continuous anodizing device, and film forming method

Abstract

An anodizing device has: a power supply drum that supports, in close contact therewith, a web consisting of an anodizable metal and has a part configured with a conductive material, to which the web is closely attached; a counter electrode provided facing the power supply drum; an electrolysis tank filled with an electrolyte, into which part of the power supply drum and the counter electrode are immersed; a protection member formed of a non-conductive material that protects the lateral direction end portions of the web supported by the power supply drum in close contact therewith and a portion of the power supply drum, to which the web is not closely attached, from the electrolyte; and a driver adapted to make the web and the protection member travel concurrently in the electrolyte in synchronization with the circumferential speed of the power supply drum.

What is claimed is: 
     
         1 . An anodizing device, comprising:
 a power supply drum which is in close contact with a web made of an anodizable metal or a web made of composite conductive metal foil with at least one surface comprising an anodizable metal and as such supports the web in a state where the web is being wound around the power supply drum, and in which at least a portion that is in close contact with the web is constituted of a conductive material;   a counter electrode that is disposed to face the power supply drum;   an electrolytic tank that is filled with an electrolytic solution into which a portion of the power supply drum which is in close contact with and supports the web and the counter electrode are dipped;   a protective member made of a nonconductive material that overlaps an end portion in a short-length direction of the web that is supported by the power supply drum in close contact with the web and a portion of the power supply drum that is not in close contact with the web so as to protect the portions from the electrolytic solution; and   a driver adapted to cause the web which is in close contact with the power supply drum and the protective member to run together in the electrolytic solution in synchronization with a circumferential speed of the power supply drum,   wherein provided that a tension per width that is applied to the web wound around the power supply drum is represented by T (N/m) and a radius of the power supply drum is represented by R (m), a value of the tension T per width that is applied to the web caused to run together in the electrolytic solution is 1,000×R or greater.   
     
     
         2 . The anodizing device according to  claim 1 ,
 wherein the tension T (N/m) per width of a value ranging from 1,000×R to 10,000×R is applied to the web.   
     
     
         3 . The anodizing device according to  claim 1 ,
 wherein in the power supply drum, a surface of the portion that is in close contact with the web is constituted of an electron conductive inorganic compound.   
     
     
         4 . The anodizing device according to  claim 3 ,
 wherein the electron conductive inorganic compound is at least one out of carbon or graphite, iridium oxide, titanium nitride, titanium carbide, titanium carbonitride, silicon nitride, silicon carbide, and silicon carbonitride.   
     
     
         5 . The anodizing device according to  claim 3 ,
 wherein in the power supply drum, an underlayer of the surface of the portion that is in close contact with the web is constituted of metal, and the metal of the underlayer is an anodizable metal.   
     
     
         6 . The anodizing device according to  claim 5 ,
 wherein the anodizable metal is aluminum.   
     
     
         7 . The anodizing device according to  claim 1 , further comprising a circulator adapted to move the electrolytic solution present in a gap between the counter electrode and the web that is supported by the power supply drum in close contact with the web out of the gap. 
     
     
         8 . The anodizing device according to  claim 7 ,
 wherein the circulator moves the electrolytic solution present in the gap in a direction approximately in parallel with a longitudinal direction of the web.   
     
     
         9 . The anodizing device according to  claim 7 ,
 wherein an opening portion is disposed in the counter electrode, and   the circulator supplies, through the opening portion, the electrolytic solution to the gap between the counter electrode and the web that is supported by the power supply drum in close contact with the web.   
     
     
         10 . The anodizing device according to  claim 7 ,
 wherein the circulator discharges the electrolytic solution in the gap in a direction approximately in parallel with the longitudinal direction of the web.   
     
     
         11 . The anodizing device according to  claim 7 , further comprising a cover member that blocks a second opening in a direction of a rotating shaft of the power supply drum among openings of the gap,
 wherein by the circulator, the electrolytic solution in the gap is discharged from a first opening in a direction approximately in parallel with the longitudinal direction of the web among openings of the gap.   
     
     
         12 . The anodizing device according to  claim 11 ,
 wherein the cover member is fixed to the electrolytic tank or the counter electrode.   
     
     
         13 . The anodizing device according to  claim 11 ,
 wherein the cover member is fixed to the rotating shaft of the power supply drum or is relatively rotatable.   
     
     
         14 . The anodizing device according to  claim 1 , further comprising a power supplier adapted to apply current to the web, the power supplier being disposed in a position above a liquid surface of the electrolytic solution. 
     
     
         15 . The anodizing device according to  claim 14 ,
 wherein the power supplier has a first power supply member that comes into contact with a metal portion of the power supply drum.   
     
     
         16 . The anodizing device according to  claim 14 ,
 wherein the power supplier has a second power supply member that comes into contact with the web.   
     
     
         17 . The anodizing device according to  claim 14 ,
 wherein the first and second power supply members are metal rolls or carbon rolls.   
     
     
         18 . The anodizing device according to  claim 14 ,
 wherein the first and second power supply members are metal brushes or carbon brushes.   
     
     
         19 . The anodizing device according to  claim 1 , further comprising a permeation preventer adapted to prevent the electrolytic solution from permeating an opened area that faces an area where the web is wound around the power supply drum. 
     
     
         20 . The anodizing device according to  claim 19 ,
 wherein the permeation preventer has a roller that comes into contact with a second surface of the web opposite with a first surface in contact with the power supply drum, or has a blade member that comes into contact with the second surface.   
     
     
         21 . The anodizing device according to  claim 20 ,
 wherein the roller that comes into contact with the second surface or the blade member that comes into contact with the second surface is disposed either at a surface of the electrolytic solution where the web comes into contact with the electrolytic solution or a surface of the electrolytic solution where the web is separated from the electrolytic solution, or at both the surfaces.   
     
     
         22 . The anodizing device according to  claim 1 ,
 wherein the rotating shaft of the power supply drum is placed in a position below the liquid surface of the electrolytic solution.   
     
     
         23 . The anodizing device according to  claim 1 ,
 wherein the power supply drum has a concavity in which the web runs while coming into contact with an inside thereof.   
     
     
         24 . The anodizing device according to  claim 1 , further comprising a guide roller that presses the protective member against the power supply drum. 
     
     
         25 . The anodizing device according to  claim 1 ,
 wherein the counter electrode has a large number of through-holes.   
     
     
         26 . The anodizing device according to  claim 1 ,
 wherein an interval between the power supply drum and the counter electrode is larger either in a region where the web supported by the power supply drum comes into contact with the electrolytic solution or a region where the web is separated from the electrolytic solution, or in both the regions, than that in a central region where the web is dipped into the electrolytic solution.   
     
     
         27 . The anodizing device according to  claim 1 ,
 wherein the protective member comprises nonconductive rubber or metal foil which is covered with nonconductive rubber.   
     
     
         28 . The anodizing device according to  claim 1 ,
 wherein the protective member has an adhesive material on a side that comes into close contact with the web.   
     
     
         29 . The anodizing device according to  claim 1 ,
 wherein a potential of the counter electrode exhibits a negative polarity against ground.   
     
     
         30 . The anodizing device according to  claim 1 ,
 wherein a potential of the web is equal to a potential of the ground, and a power source for electrolysis is an output insulated from the ground.   
     
     
         31 . The anodizing device according to  claim 29 , further comprising a monitor adapted to monitor a voltage of the power supply drum with respect to the potential of the ground. 
     
     
         32 . A continuous anodizing device,
 wherein a large number of the anodizing devices according to  claim 1  are arranged in series.   
     
     
         33 . A film forming method,
 wherein the anodizing device according to  claim 1  is used to form an anodic oxide film on one surface of the web.