公开(公告)号：US4984855A

公开(公告)日：1991-01-15

申请号：US268509

申请日：1988-11-08

申请人： Masao Horiuti ,  Shunichi Kodama ,  Kenji Kuroda

发明人： Masao Horiuti ,  Shunichi Kodama ,  Kenji Kuroda

IPC分类号： C23C18/36

CPC分类号： C23C18/36 ,  Y10S362/80

摘要： An ultra-black film is disclosed, which essentially consists of a base, a Ni-P alloy layer formed on said base and a phosphate layer formed on said Ni-P layer, the spectral reflectance of said ultra-black film being 0.04 to 0.4%. The ultra-black film is obtainable by one of four methods, i.e., a first method, which comprises sequential steps of effecting primary etching of a Ni-P alloy film surface with an aqueous nitric acid solution and effecting secondary etching of the surface with an aqueous sulfuric-acid-containing nitrate solution, a second method, which comprises of effecting said secondary etching of a Ni-P alloy film surface a third method, which comprises sequential steps of forming a Ni-P alloy film on a base by using a plating solution basically composed of nickel salt, sodium hypophosphate, D, L-malic acid and malonic acid and effecting said secondary etching to the alloy film surface and a fourth method, which comprises sequential steps of forming a Ni-P alloy film on a base by using a plating solution basically composed of nickel salt, sodium hypophosphite, D, L-malic acid and succinic acid or basically composed of nickel salt, sodium hypophosphite, D, L-malic acid lactic acid and malonic acid and effecting said primary etching to the surface.