Abstract:
Bright and smooth functional chromium is deposited using a plating bath containing chromic acid, 40-150 g/l sulfoacetic acid, an iodine-releasing agent e.g. - iodate, and a nitrogen organic compound e.g. glycine as a depolariser. The bath is otherwise free of carboxylic acids, fluoride, bromide and selenium ions. The process can be operated at conventional plating current densities e.g. 1-10 asi:.
Abstract:
The inventors disclose a process for reducing high current density edge buildup dendrite formation, edge burn, controlling high current density roughness, grain size, and orientation of a zinc coating obtained from an aqueous zinc acidic electrogalvanic coating bath comprising passing a high density current from a zinc anode in the bath to a metal cathode in the bath for a period of time sufficient to deposit a zinc coating on the cathode. The bath contains greater than about 5g/l of a water soluble zinc organosulfonate. A random or block polyoxyalkylene glycol homopolymer or copolymer based on 2 to about 4 carbon atom alkylene oxides. The inventors employ current densities from about 250 to about 4,000 ASF, and optionally, a sulfonated condensation product of naphthalene and formaldehyde, a boron oxide compound, and a lignin compound. The invention also comprises bath compositions.
Abstract:
This invention relates to aqueous solutions containing Ni cation and hypophosphite anion which have a Ni cation concentration greater than 36 grams /liter. Such solutions have utility in electroless nickel plating baths and processes as make-up solutions and replenishing solutions. The increased concentration of Ni cation results from the addition of the nickel salt of an alkyl sulfonic acid to the solution.
Abstract:
The inventors disclose a process for reducing high current density edge buildup dendrite formation, edge burn, controlling high current density roughness, grain size, and orientation of a zinc coating obtained from an aqueous zinc acidic electrogalvanic coating bath comprising passing a high density current from a zinc anode in the bath to a metal cathode in the bath for a period of time sufficient to deposit a zinc coating on the cathode. The bath contains greater than about 5g/l of a water soluble zinc organosulfonate. A random or block polyoxyalkylene glycol homopolymer or copolymer based on 2 to about 4 carbon atom alkylene oxides. The inventors employ current densities from about 250 to about 4,000 ASF, and optionally, a sulfonated condensation product of naphthalene and formaldehyde, a boron oxide compound, and a lignin compound. The invention also comprises bath compositions.