Abstract: An electroforming apparatus, in particular for the manufacture of CD/LD data media molding tools, comprises an anode assembly and a rotatable cathode assembly spaced therefrom, and a stationary nozzle means for ejecting an electrolytic fluid into the space between the anode and cathode assemblies. An annular part of the cathode assembly surrounding a molding tool blank is penetrated by a plurality of circumferentially distributed flow passages, the inlet ends thereof are disposed to successively come into alignment with the nozzle means upon rotation of the cathode assembly so that the electrolytic fluid ejected from the nozzle means is received by the flow passages and guided thereby into the space between the anode and cathode assemblies. The width of the spac can thereby substantially be minimized.

Abstract: A method and an apparatus for thermal process control in electroforming stampers for the production of CD/LD data carriers or the like. The temperature of an electrolytic solution in an electroforming cell is maintained at a value nearest a specific maximum temperature by raising or lowering the temperature of the electrolytic solution in a storage tank provided outside of the electroforming cell as a function of the temperature measured in a cathode space of the electroforming cell. A temperature sensor is disposed in or near the cathode space adjacent an electrolyte injection nozzle in a space between the anode and cathode means for supplying signals to a control unit. The temperature sensor and the injection nozzle are preferably assembled into a single mounting unit. The electroforming process can thus be run with an optimum effectivity in the vicinity of a maximum permissible temperature of the electrolytic solution.