Abstract: An aqueous acid bath for galvanic precipitation of copper is disclosed. The copper plating composition comprises at least one polymer phenazonium compound and .beta.-naphtholalkoxylate. A method for using such a bath for deposition of copper coatings is also disclosed. The resultant copper coatings are smooth and bright with substantially no fine roughness or pitting.

Abstract: An aqueous acid bath for the galvanic deposition of bright, ductile and smooth copper coats which is suitable for decorative purposes as well as for strengthening the conductors of printed circuits. The bath is characterized by a content of polyalkylene glycol ether. When combined with thio compounds containing water-soluble groups, these additions produce an electrolyte with excellent stability. Polymeric phenazonium compounds, polymeric nitrogen compounds and/or thio compounds containing nitrogen may also be successfully combined, in addition, depending on the desired properties.