| abstract |
(57) [Summary]n[Structure] Silicon alkoxide, aluminum and Apply the solution containing the boron compound to the substrate and bake it. In the oxide film to be formed, each constituent element is SiO 2 Is 5 0-90 mol%, Al 2 O 3 Is 3 to 40 mol%, B 2 O 3 But Uniform pores of 3 to 40 mol% and 10 μm or less It is a hydrophilic coating that does not contain the alkali metal Heat exchanger with its coating formed on the metal surface or its steam Generator.n[Effect] The metal surface on which the film of the present invention is formed is a heat exchanger. It has hydrophilicity and water flowability required for condensers of In addition, since it does not contain alkali silicate, it can be used severely. Performance does not change over a long period of time Yes. |