摘要 |
<p>An alkaline zinc-nickel electroplating bath comprises zinc ions, nickel ions, a primary brightener which is an N-methylpyridinium compound substituted at the 3-position of the pyridine ring with a carboxylate group or a group hydrolyzable to a carboxylate group and a secondary brightener which is an aliphatic amine. An example of a preferred brightener is N-methylpyridinium-3-carboxylate or a salt thereof. A preferred polyamine is a polyethyleimine. By the present invention, a mirror bright zinc-nickel deposit can be obtained having more than 4% by weight nickel, without blistering or decomposition of the primary brightener.</p> |