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 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. The modifier for hydrophilicity includes a modified polyvinyl alcohol containing a group represented by formula (I) on a side chain thereof. In the formula, n represents an integer of 1 to 500, R¹ represents a hydrogen atom or an alkyl group containing 1 to 4 carbon atoms, and R² represents a hydrogen atom or a methyl group. The group represented by formula (I) accounts for 0.1 to 10 mole percent of the sum of hydroxyl groups and acetoxy groups in the modified polyvinyl alcohol, and the modified polyvinyl alcohol accounts for 0.1 to 30% by mass relative to the modifier for hydrophilicity;