Method and apparatus for wet treatment of solid surfaces

摘要

The object of the invention is to accomplish surface treatment such as cleaning, etching or after-treatment of parts or semi-processed articles for the manufacture of industrial or medical products without raising the problem of environmental pollution and without damaging or contaminating the treated articles. Water is electrolyzed in a tank which is partitioned by a porous membrane into an anode chamber and a cathode chamber to prepare a fresh anodic water containing H+ ion in the anode chamber and a fresh cathodic water containing OH- ion in the cathode chamber. The fresh anodic water and the fresh cathodic water are separately discharged from the electrolysis tank, and selected one of the anodic water and the cathodic water is brought into contact with the object of wet treatment. The efficiency of electrolysis of water can be enhanced by adding a small amount of an electrolysis aid such as carbon dioxide gas or ammonium acetate to water and/or by irradiating water under electrolysis with an electromagnetic wave having an wavelength not longer than 400 nm or not shorter than 3000 nm.