METHOD FOR COATING ALUMINUM FIN MATERIAL WITH HYDROPHILIC FILM, ALUMINUM FIN MATERIAL, AND ALUMINUM HEAT EXCHANGER

摘要

Provided are: a heat exchanger surface treatment method whereby it is possible to form a hydrophilic film exhibiting extremely high hydrophilicity (superhydrophilicity) and therefore also having excellent maintenance of hydrophilicity as well as excellent adhesion of the hydrophilic film and a metal surface in a state in which moisture adheres to the hydrophilic film; an aluminum fin material in which a hydrophilic film is formed on the surface of a fin by the aforementioned method; and an aluminum heat exchanger which uses the aluminum fin material. In the present invention, a metal surface is coated with a hydrophilic film using a hydrophilizing treatment agent containing a hydrophilic resin and crosslinking microparticles, and containing a specific (meth)acrylic resin, polyvinyl alcohol, and a polyalkylene ether resin having a specific molecular weight as the hydrophilic resin, the blending of each component being adjusted in a specific range.