Electroless nickel phosphorus cobalt plating bath and electroless nickel phosphorus cobalt coating

摘要

An electroless nickel-phosphorus-cobalt plating bath contains a water-soluble nickel salt, a hypophosphorous acid salt, a cobalt-containing compound and a heavy metal compound, and additionally contains at least one component selected from the group consisting of an acetylene compound, an iodide ion source or an iodic acid ion source, and a nitro-group-containing aromatic compound that contains at least one nitro group. The concentration of the acetylene compound is 10 to 120 mg/L, the concentration of the iodide ion source or the iodic acid ion source is 10 to 4000 mg/L, and the concentration of the nitro-group-containing aromatic compound is 0.1 to 5000 mg/L.