Patents by Inventor Volker Wohlfarth

Volker Wohlfarth has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11339492
    Abstract: The present invention relates to a method for the galvanic deposition of zinc and zinc alloy coatings from an alkaline coating bath with a reduced degradation of organic bath additives. An electrode that contains metallic manganese and/or manganese oxide and is insoluble in the bath is hereby used as an anode. The electrode is produced from metallic manganese or an alloy comprising at least 5% by weight of manganese, or from an electrically conductive substrate and a metallic manganese and/or manganese oxide-containing coating applied thereto, or from a composite material, wherein the coating and the composite material comprise at least 5% by weight of manganese. The method according to the invention is particularly suitable for the galvanic deposition of zinc-nickel alloy coatings from alkaline zinc-nickel baths since the formation of cyanides can be very effectively inhibited.
    Type: Grant
    Filed: February 5, 2018
    Date of Patent: May 24, 2022
    Assignee: Dr.-Ing. Max Schlötter GmbH & Co. KG
    Inventors: Volker Wohlfarth, Ralph Krauss, Michael Zöllinger
  • Publication number: 20220064813
    Abstract: A method of electroplating a stress-free copper film on a substrate includes: providing the substrate; providing an electroplating bath that includes a copper salt, an acid, a leveler, a chlorine compound, an accelerator, a suppressor; and water; heating the electroplating bath to 25 to 60° C.; and electroplating the substrate in the electroplating bath to form the stress-free copper film while maintaining the electroplating bath at 25 to 60° C. The leveler is an organic compound containing an amine group. The method further includes annealing the stress-free copper film at 60-260° C. for 0.5 to 2 hours, or at 60-120° C. for 0.5 to 2 hours. A stress-free electroplated copper film is also disclosed.
    Type: Application
    Filed: February 3, 2021
    Publication date: March 3, 2022
    Inventors: Yun ZHANG, Xingxing ZHANG, Volker WOHLFARTH, Jing WANG, Peipei DONG, Wei ZHAO
  • Publication number: 20190376200
    Abstract: The present invention relates to a method for the galvanic deposition of zinc and zinc alloy coatings from an alkaline coating bath with a reduced degradation of organic bath additives. An electrode that contains metallic manganese and/or manganese oxide and is insoluble in the bath is hereby used as the anode, and is produced from metallic manganese or a manganese-containing alloy, the manganese-containing alloy comprising at least 5% by weight of manganese, or is produced from an electrically conductive substrate and a metallic manganese and/or manganese oxide-containing coating applied thereto, or is produced from a composite material, with both the metallic manganese and/or manganese oxide-containing coating and the composite material comprising at least 5% by weight of manganese, based on the total amount of manganese resulting from metallic manganese and manganese oxide.
    Type: Application
    Filed: February 5, 2018
    Publication date: December 12, 2019
    Applicant: Dr.-Ing. Max Schlötter GmbH & Co. KG
    Inventors: Volker Wohlfarth, Ralph Krauss, Michael Zöllinger