| 摘要 |
PURPOSE:To improve defatting property and corrosion resistance by forming a hydrophilic inorg. film layer on a surface of Al or Al alloy and providing further a hydrophilic org. high polymer film layer having a specific degree of polymn. thereon. CONSTITUTION:The hydrophilic inorg. film layer 2 is formed on the surface of an Al fin 1 and the hydrophilic org. high polymer film layer 4 is provided thereon. When the fin 1 is formed after coating press oil 3 thereto, the layer 2, the layer 4 and the oil 3 are layered on the fin 1. When the fin is defatted, the layer 4 and the layer of the oil 3 are easily removed and even if the layer 4 remains partly, the hydrophilicity is not spoiled at all. Even if a pinhole 5 exists in the film in the stage of forming the inorg. film layer, the film defect 5 is sealed by providing the org. film layer 4, by which the corrosion resistance is improved. The defatting property, hydrophilicity and corrosion resistance of the material 1 are improved by the above-mentioned method. |
