Modifier for hydrophilicity, hydrophilic modification method and aluminum material or aluminum alloy material modified hydrophilic thereby

摘要

A modifier for hydrophilicity and a hydrophilic modification method which are capable of suppressing not only the odor of the resulting hydrophilic coat itself but also the unpleasant odor emanation after exposure to odorants and retaining the hydrophilicity even during a long period of use, and an aluminum material or aluminum alloy material by said hydrophilic modification method, which is used suitably for heat exchangers and the like are provided. ;A modifier for hydrophilicity which comprises a hydroxyl group- and ester bond-containing radical polymer having a number average molecular weight of 1,000 to 1,000,000, ;said hydroxyl group accounting for 50 to 99.9 mole percent and said ester bond accounting for 0.1 to 50 mole percent respectively, of the sum of the hydroxyl groups and ester bonds in the radical polymer, and ;said radical polymer accounting for 0.1 to 30% by mass relative to said modifier for hydrophilicity.