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Copper plating is the process in which a layer of copper is deposited on the item to be plated by using an electric current. Three basic types of processes are commercially available based upon the complexing system utilized: *alkaline-(several modifications of cyanide and non-cyanide) complexed bath *acid-(sulfate and fluoroborate) complexed bath *mildly alkaline-(pyro phosphate) complexed bath With a higher current, hydrogen bubbles will form on the item to be plated, leaving surface imperfections. Often various other chemicals are added to improve plating uniformity and brightness. Without some form of additive, it is almost impossible to obtain a smooth plated surface. These additives can be anything from dish soap to proprietary compounds. == Limitations == Copper is an active metal (having a low ionization energy, so it loses electrons readily); hence, it does not readily plate onto a passivated surface, making direct plating of iron-based metals difficult. For this reason, such surfaces are first given a nickel-strike base coat, to which the copper can adhere. The plating seen in chemistry classes, often obtained with a coin and copper-sulphate bath, is in fact deposition, as opposed to plating. Subjecting the surface to any wear causes the deposit – which is not bonded – to spalt. Running such a bath for longer periods, one can readily observe the grainy texture left by deposition, whereas plating results in a smooth surface. Commercial platers typically use a copper-cyanide solution, which retains a high concentration of copper. However, it is inherently dangerous, due to the highly toxic nature of cyanide. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Copper plating」の詳細全文を読む スポンサード リンク
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