| 摘要 |
PURPOSE:To prepare an electroless plating bath for stably forming a magnetic film having high coercive force and satisfactory squareness ratio by adding malonic acid and pyrophosphoric acid groups as a complexing agent to an aq. soln. contg. metal ions such as Co and Zn ions and a reducing agent for the metal ions. CONSTITUTION:An electroless plating bath is prepd. by adding about 0.001-4.0mol/l malonic acid groups and about 0.0001-1.50mol/l pyrophosphoric acid groups as a complexing agent to an aq. soln. contg. about 0.002-2mol/l Co ions and about 0.00001-1.5mol/l Zn ions as metal ions in the form of sulfates or the like and about 0.001-1.3mol/l reducing agent for the metal ions such as hypophosphite. A pH buffer, a brightener and other additives may be added to the bath within limits not prejudicial to the purpose and effect. The pH of the bath is about 3-14.5. When the electroless plating bath is used, a magnetic film for a magnetic recording medium such as a magnetic disk is stably formed. The pref. thickness of the film is about 0.005-5mum. |
