Process for producing a cutting base

US4640745A · kind A · utility

Assignee

• Teldec Schallplatten GmbH · DE

Inventors

• Herbert Knothe · Neumünster, DE
• Klaus Roschmann · Uznach, CH

Key dates

• Filing date: Sep 9, 1985
• Grant date: Feb 3, 1987
• Expiry date: Sep 9, 2005

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C25D7/00
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

Process for producing a sound recording cutting base, which includes precipitating a cuttable copper layer on a substrate from an electroplating bath, the copper layer having an initial grain size and having recrystallizing characteristics as a result of the bath's composition, convection and current density, characterized in that in order to extend recrystallization time, substances are added to the bath which, by their incorporation in the copper layer, stabilize the latter in such a manner that recrystallization is prevented or delayed, the substances including leveling agents added in effective amounts to prevent formation of layer-grain crystals of copper having a grain size which substantially exceeds the initial grain-size.