Siemens Aktiengesellschaft

Georg Iwantscheff

Richard Doetzer

Richard Dotzer

Egmont Scheubeck

The invention provides a high-purity electroaluminum layer having a purity of greater than 99.99% and, preferably, a thickness of 10 to 20 .mu.m which serves as a gas barrier layer, particularly for hydrogen, oxygen, tritium and water vapor, for metallic materials and nonmetallic materials such as glass, quartz, ceramic and cermets with an electroconductive surface as well as for conductive plastics. By post-treatment, the electroaluminum layer can be compacted. The electroaluminum layer is precipitated by electroplating from aprotic oxygen-free and anhydrous electrolyte media of the general formula M.sup.I X.2AlR.sub.3.nLsm, wherein M.sup.I is an alkali metal ion or a quaternary onium ion, X is a halogen ion, preferably F.sup.- or Cl.sup.-, R is an alkyl radical, preferably CH.sub.3, C.sub.2 H.sub.5, C.sub.3 H.sub.7 or C.sub.4 H.sub.9, Lsm is an aromatic solvent molecule, preferably toluene, ethyl benzene, xylene or a mixture thereof, and n=0 to 12, at a bath temperature of 50.degree. to 110.degree. C. and a current density of 0.5 to 10 A/dm.sup.2 under intensive bath agitation. Electroplating may be conducted in the presence of an aromatic solvent.

Gas barrier layer for metallic and nonmetallic materials

The invention provides an ion barrier formed of a high-purity electroplated aluminum layer (purity &gt;99.99%) which preferably has a thickness of 10 to 20 .mu.m for use on structural parts and shapes of metals and nonmetals, in particular on polyolefins. If desired, the electroplated aluminum layer can be compacted and/or anodically oxidized by post-treatment. The electroplated aluminum layer prevents the intrusion of metal and nonmetal ions into nonmetals, particularly plastic (for example polyolefins), and their penetration to metal surfaces. The deposition of the electroplated aluminum layer occurs from aprotic, oxygen-free and anhydrous electrolyte media of the general formula M.sup.I X.2AlR.sub.3.nLsm, wherein M.sup.I is an alkali metal ion or a quaternary onium ion, X is a halogen ion, preferably F.sup.- or Cl.sup.-, R is an alkyl radical, preferably CH.sub.3, C.sub.2 H.sub.5, C.sub.3 H.sub.7 or C.sub.4 H.sub.9, Lsm is an aromatic solvent molecule, preferably toluene, ethyl benzene, xylene or a mixture thereof, and n=0 to 12, at a bath temperature of 50.degree. to 110.degree. C. and a current density of 0.5 to 10 A/dm.sup. 2 under intensive bath movement. The media may possibly be in the presence of an aromatic solvent.

Ion barrier layer on metals and nonmetals

A method for processing biomaterial, particularly meat, in which coarsely comminuted biomaterial with a moisture of up to 80% is dried in a processing vessel down to a residual moisture of about 5-10% and subsequently burned at a pressure of 20 to 40 bar in pure oxygen permitting metal traces, particularly mercury, cadmium, lead and arsenic, to be readily determined analytically in the process solution.

Method for processing biomaterials

A method for pretreating the surfaces of electroconductive materials such as metals which are to be electroplated in an aprotic oxygen- and water-free organoaluminum electrolytic media in which the last mechanical operation generating fresh and bright surfaces is performed under the exclusion of air, oxygen, and moisture using a protective gas or protective liquid and the part being treated maintained in such an environment until electroplated.

Growing community of inventors

Nuernberg, Germany

Georg Iwantscheff