| 摘要 |
PURPOSE:To obtain a selective heat collecting membrane having high heat absorption rate, and excellent thermal conductivity and weather resistance by producing a thin oxidized film treated with aluminum material as a solar heat collecting base plate and secondarily electrolyzing in the prescribed solution. CONSTITUTION:In manufacture, aluminum and aluminum alloy are desalted, etched, and neutralized in accordance with an ordinary method, and are electrolyzed in AC or DC in electrolytic solution (containing approx. 5-50% of phosphoric acid) cntaining phosphoric acid or its salt, thereby forming an oxidized film having a thickness less than 0.1mum. Then, one or more of metallic salts such as iron, magnesium, tin, lead, gold, silver, cobalt, nickel, copper, vanadium, etc. are mixed and the electrolysis is performed in dissolved electrolyte. In this manner, it is contained in the fine pores of the membrance in the form of metal, metal oxide, intermetallic compound, thereby forming the prescribed selectively heat collecting membrance. |
