摘要:
A method of preparing a hard disc comprising steps of:immersing an aluminum or aluminum alloy substrate in a zincate solution containing a zinc compound, an alkali hydroxide, and at least one amine to thereby form a zincate film on the surface of the substrate,immersing the zincate film-formed substrate in an electroless nickel plating solution comprising a water-soluble nickel salt, a complexing agent, and a hypophosphite to thereby form a nickel--phosphorus alloy layer on the surface of the zincate film-coated substrate, and forming a magnetic layer on the nickel--phosphorus alloy layer.
摘要:
An amine, such as a triethanol amine or ethylenediamine is added to an alkaline electroless gold plating solution comprising a gold salt and a boron-based reducing agent to deposit a gold film having good appearance and high throwing power on a workpiece at a high deposition rate.