抄録
Boric acid has been an essential substance in plating technology for obtaining good film properties and for improving bath life. However, there are restrict ions against Boron in waste water ; therefore the development of a boric acid free nickel electroplating bath was in demanded.In our previous paper, we attempted to develop a boric acid-free sulfamate Ni plating bath. We examined over 20 kinds of plating solutions with alternative chemicals, and found that acetic acid, propionic acid, Ni acetate, and citric acid were recognized as potential candidates to obtain similar film properties and appearance. This paper reports the evaluation of deposited film properties obtained using these four kinds of organic acid baths. Acetic acid, propionic acid, and Ni acetate, as replacements for boric acid, exhibited similar properties as those obtained by boric acid. The propionic acid bath showed less pit defects even after thick film formation without surfactants. Accordingly, it appears to be a favorable boric acid replacement for those applications that require thicker require films.
