Etching method for resin molded article and etching process system for resin molded article

Abstract

The processing system (1) is provided with an etching tank (2) and a circulation pipe (7) that exits from the bottom portion of the etching tank (2) and returns to the etching tank (2). The circulation pipe (7) is provided with a liquid feed pump (8), a heat exchanger (9), a sulfuric acid concentration meter (10), and an oxidant concentration meter (11). The sulfuric acid concentration meter (10) and the oxidant concentration meter (11) can transmit measurement results to a calculation/control device (12). The etching tank (2) can be replenished with hydrogen peroxide water, sulfuric acid, and pure water through a hydrogen peroxide water supply line (13), a sulfuric acid supply line (14), and a pure water supply line (15). The calculation/control device (12) can adjust the supply amounts of hydrogen peroxide water, sulfuric acid, and pure water to respective desired amounts. Such a processing system enables etching of a resin molded article while maintaining both the sulfuric acid concentration and the oxidant concentration of a sulfuric acid solution that is free from hexavalent chromic acid or permanganic acid and contains an oxidizing substance obtained by mixing sulfuric acid and hydrogen peroxide water.

Dependencies are inferred from the claim text.