| abstract |
A hydrophilizing composition which contains no chromium and imparts excellent corrosion resistance and long-lasting hydrophilicity to a heat exchanger made of aluminum. The hydrophilizing agent for metallic materials comprises: (A) a hydrophilic polymer having at least one nonionic functional group selected from the group consisting of primary amide, secondary amide, tertiary amide, hydroxy, and polyoxyalkylene groups; (B) a hydrophilic polymer having at least one ionic functional group selected from the group consisting of sulfo, phosphonate, carboxyl, primary amino, secondary amino, tertiary amino, and quaternary ammonium groups; (C) a vanadium compound; and (D) a compound having at least one element selected from the group consisting of Zr, Ti, and Si. |