| 摘要 |
PURPOSE:To form a blackbody film having a low light reflection coefficient and excellent mechanical strength by plating a nickel-phosphorus alloy film on a base material, and etching the surface of the plating film with an aq. nitrate soln. contg. sulfuric acid. CONSTITUTION:The surface of a base material is degreased, pickled, activated, if necessary, and then strike-plated with nickel. The plated base material is dipped in an electroless nickel-phosphorus alloy plating soln. By this method, a nickel-phosphorus alloy plating film contg. about 6-9% P is formed on the base material surface preferably in about 70-80mum thickness. The surface of the plating film is then etched with an aq. soln. contg. about 200-450g/l sodium nitrate and about 300-700g/l sulfuric acid. As a result, the surface is covered with many micropores having the size observable by an electron microscope, a flocculent microstructure is formed on the surface of the micropore, and a base material having the blackbody nickel-phosphorus alloy film having 0.1-0.4% light reflection coefficient in 320-2,200nm wavelength range is obtained. |
