To provide a manufacturing method of an anode foil for aluminum electrolytic capacitors of which capacitance is high with a good leakage current characteristic.
The manufacturing method of an anode foil for aluminum electrolytic capacitors includes a step in which an etched aluminum foil is submerged in the pure water at high temperature so that a hydration coating is formed on the surface of the aluminum foil, a step in which an organic acid sticks to the surface of the hydration coating, a chemical conversion treatment step which is performed for the aluminum foil up to a predetermined voltage in at least two stages, and a depolarizing treatment step and a re-chemical conversion treatment step after the chemical conversion treatment step. The chemical conversion treatment step uses a phosphate aqueous solution as a chemical conversion liquid to which a first voltage is applied. Such type of liquid as different from the phosphate aqueous solution is used as the chemical conversion liquid to which the last chemical conversion treatment is applied.
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