PURPOSE: To obtain an electroless plating bath giving a recording medium with favorable magnetic characteristics by adding malic acid and malonic acid groups to a soln. contg. Co and Ni ions, a reducing agent, a Ph buffer, a pH adjusting agent and Zn ions.
CONSTITUTION: Co and Ni ions are dissolved in the form of salts such as sulfates, a reducing agent such as hypophosphite, a pH buffer such as an ammonium salt, a pH adjusting agent and Zn ions are added, and malic acid and malonic acid groups are further added in the form of salts such as sodium malate and sodium malonate to obtain an electroless plating bath. This plating bath is used in the manufacture of a magnetic recording medium (magnetic film) such as a magnetic disk. The plating bath is stabilized by the composition and gives a magnetic film with favorable magnetic characteristics.
KANEKO MAMORU
MIYAJIMA MASAO
