Electrolyzing apparatus

Abstract

An object of the present invention is to provide an electrolysis apparatus that can prevent formation of surface defects such as white bands on an obtained aluminum support for a planographic printing plate even when electrolyzing an aluminum strip at a high current density while conveying the aluminum strip at a high conveyance velocity. The electrolysis apparatus is used for electrolyzing a metal strip conveyed in one direction. The apparatus includes a plurality of electrolysis cells arranged in series, wherein the metal strip is electrolyzed in an acidic electrolyte by applying an alternating current. In an electrolysis cell disposed in the downstream-most position with respect to the conveyance direction of the metal strip, electrolysis is carried out at a lower current density than in an electrolysis cell disposed in an upstream electrolysis cell with respect to the conveyance direction.

Description

technical field [0001] The present invention relates to an electrolysis apparatus, and more particularly, to an electrolysis apparatus for electrolyzing a metal strip under high-density current without forming any defects on its surface while conveying the metal strip at a high conveying speed. Background technique [0002] Lithographic printing plates are usually produced by a process involving the following steps: [0003] a) roughening one or both sides of the aluminum strip to form an aluminum matrix having a roughened surface on one or both sides; [0004] b) anodizing the aluminum substrate; then [0005] c) Coating a solution containing a photosensitive, thermosensitive or photopolymerizable resin on the rough surface of the aluminum substrate to form an imaging layer. [0006] Aluminum strip is usually roughened by a process involving the following steps: [0007] a) mechanical roughening; one or both sides of the aluminum strip are mechanically scraped using a cy...

AI Technical Summary

Problems solved by technology

[0012] However, when the aluminum strip is electrolyzed at a higher current density and transported at a higher transport speed, many different surface defects are sometimes formed on the surface of the obtained substrate, such as white bands with different densities, chatter marks (along Striped defects extending along the width of the substrate) and streaks extending along the width (sometimes formed on the surface of the obtained aluminum substrate)

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