Degussa Aktiengesellschaft

Degussa - Huls Ag

Dmc2 Degussa Metals Catalysts Cerdec Ag

Dequssa Ag

Werner Kuhn

Wolfgang Zilske

Stefan Wieland

Bernd Kempf

Erika Kreuter

Meike Roos

Ernst Drost

The invention provides a supported metal membrane which contains a metal membrane on a support surface of a porous membrane support. The supported metal membrane is obtainable by applying the metal membrane to the support surface of the membrane support, wherein the pores in the membrane support are sealed, at least in the region of the support surface, prior to applying the metal membrane and are opened by removing the auxiliary substance only after applying the metal membrane.

Supported metal membrane, a process for its preparation and use

Cyanide-free electroplating bath for the deposition of gold and gold

Crack-free, bright platinum layers with thicknesses of more than 100 .mu.m are obtained from electroplating baths which contain 5 to 30 g/l platinum as amminesulphamato complex and 20 to 400 g of a strong acid if the content of free amidosulphuric acid amounts to less than 5 g/l.

Platinum plating bath

Yellow to rose-colored gold alloy coatings with copper and silver are obtained from stable galvanic baths with a pH of 8.5 to 11 containing, 1 to 15 g/liter gold as potassium gold (I) cyanide, 5 to 50 g/liter copper as potassium copper (I) cyanide, 0.05 to 5 g/liter silver as potassium silver (I) cyanide and dipotassium hydrogenphosphate as well as alkali cyanides in amounts of up to 10 g/liter and 0.1-1 mg/liter potassium selenocyanate.

Galvanic gold alloying bath

For the direct gold plating of stainless steel parts in acid baths there is needed a pretreatment of the parts. Known processes operate with corrosive media such as strong acids and attack the surface. These disadvantages are avoided by putting the stainless steel part in an electrolytic, aqueous solution and first treating cathodically and subsequently anodically.

Process for the treatment of stainless steel for a direct galvanic gold

To produce electrolytic deposition of glossy gold/tin alloys there are employed baths having a pH below 3 which contain 1 to 20 g/l gold in the form of tetracyanoaurate (III), 0.1 to 10 g/l tin, an acid and a conducting salt, whereby the tin is in the form of a tin (IV)-oxalato complex.

Process and bath for the electrolytic deposition of gold-tin alloy

Light yellow, glossy and ductile gold-indium alloys which have a good resistance to gradual corrosion by silver sulfide are obtained from electrolytic (galvanic) baths containing 1 to 20 g/l of gold in the form of alkali or ammonium tetracyanoaurate (III), 0.5-50 g/l of indium in the form of a water soluble indium salt, a buffer or conducting salt and 0.5 to 10 mg/l of selenium and/or tellurium.

Bath and process for the electrolytic deposition of gold-indium alloys

There is described an electrolytic bath for the deposition of haze-free glossy rhodium coatings which furnish a white gold-like tint and low tension flims. This bath in addition to rhodium sulfate or phosphate, sulfuric acid and/or phosphoric acid also contains a sulfonic acid, especially an aromatic sulfonic acid, as for example, phenolsulfonic acid.

Electrolytic bath for the deposition of rhodium coatings

In the electro industry, there are needed acid gold alloy baths which give glossy, ductile coatings, operate at high current densities, and contain little non-metallic impurities. This is attained by a bath based on potassium cyanoaurate (III) and an acid whereby the bath contains at least one of the alloying metals cobalt, nickel, indium, tin, zinc, or cadmium in the form of a water soluble salt, together with an amine, an aminocarboxylic acid, or a phosphonic acid and has a pH of below 3.

Growing community of inventors

Rodenbach, Germany

Werner Kuhn