Abstract:
An electrolytic cell and a method of electrochemical oxidation of manganese(II) ions to manganese(III) ions in the electrolytic cell are described. The electrolytic cell comprises (1) an electrolyte solution of manganese(II) ions in a solution of at least one acid; (2) a cathode immersed in the electrolyte solution; and (3) an anode immersed in the electrolyte solution and spaced apart from the cathode. Various anode materials are described including vitreous carbon, reticulated vitreous carbon, woven carbon fibers, lead and lead alloy. Once the electrolyte is oxidized to form a metastable complex of manganese(III) ions, a platable plastic may be contacted with the metastable complex to etch the platable plastic. In addition, a pretreatment step may also be performed on the platable plastic prior to contacting the platable plastic with the metastable complex to condition the plastic surface.
Abstract:
a method of coating an electroplating rack used for supporting non-conductive substrates during a plating process. The method comprises the steps of contacting at least a portion of the electroplating rack with a plastisol composition, the plastisol composition having dispersed therein an effective amount of an additive having the structure: Formula (I) wherein R, R', R" and R'" are either the same or are independently selected from the group consisting of benzyl, substituted benzyl, phenyl or substituted phenyl; or :Formula (II) wherein R, R', R" and R'" are either the same or are independently selected from C I - CI O alkyl (either straight or branched chain), benzyl, substituted benzyl, phenyl, or substituted phenyl and M is a divalent metal cation, preferably selected from the group consisting of nickel, copper and zinc; and heating the electroplating rack with the plastisol composition thereon to a suitable temperature and for a sufficient time to cure the plastisol and form a solid insulating coating on the electroplating rack. The coated electroplating rack may then be used for mounting non- conductive substrates for subsequent metallization steps.
Abstract:
A process for plating metal on plastic substrates, particularly ABS substrates, without the use of chrome containing etchants is disclosed. The process involves (i) etching the plastic substrate in an acidic solution of nitrate ions, and preferably silver ions, (ii) conditioning the substrate in an aqueous solution containing an amine or ammonia, (iii) activating the substrate, preferably with a palladium activator, and (iv) plating the substrate with an electroless plating solution. The process allows for complete adherent electroless plating of plastic substrates, particularly ABS substrates, without the use of chromic etchants.
Abstract:
A method of maintaining a concentration of sulfuric acid in an electrolyte comprising manganese(III) ions in a solution of sulfuric acid. The method includes the steps of a) removing a portion of the electrolyte from the electrolytic cell to an annex tank; b) treating the removed portion of the electrolyte in the annex tank to remove moisture from the portion of the electrolyte; and c) returning the treated portion of the electrolyte to the electrolytic cell. The removed portion of the electrolyte is treated by passing a dry gas over the surface of the electrolyte in the annex tank to absorb moisture from the electrolyte and restore the concentration of sulfuric acid in the electrolyte.
Abstract:
An electroplating rack for supporting non-conductive substrates during an electrodeposition process is described. The electroplating rack is coated with a non-conductive material, such as a PVC plastisol. The electroplating rack is treated with a non-aqueous solution comprising a metallization inhibitor prior to the electrodeposition process to inhibit rack plate up when using etchants that do not contain chromic acid.
Abstract:
An electrolytic cell and a method of electrochemical oxidation of manganese (II) ions to manganese(III) ions in the electrolytic cell are described. The electrolytic cell comprises ( 1 ) an electrolyte solution of manganese(II) ions in a solution of 9 to 15 molar sulfuric acid; (2) a cathode immersed in the electrolyte solution; and (3) an anode immersed in the electrolyte solution and spaced apart from the cathode. Various anode materials are described including vitreous carbon, reticulated vitreous carbon, and woven carbon fibers.