Patents by Inventor Stefan Durdoth

Stefan Durdoth 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: 8277953
    Abstract: The present invention relates to an apparatus with a structured hard chrome layer electrodeposited onto a work-piece, the structured hard chrome layer being cup-shaped and/or labyrinth-like and/or column-shaped. The structured hard chrome layer can be electrodeposited from an electrolyte onto the work-piece, said electrolyte containing (a) a Cr (VI) compound in an amount corresponding to 50 g/l to 600 g/l of chromic acid anhydride; (b) 0.5 g/l to 10 g/l of sulphuric acid; (c) 1 g/l to 20 g/l of aliphatic sulphonic acid, comprising 1 to 6 carbon atoms; and (d) 10 g/l to 200 g/l of at least one compound forming a dense cathode film, said compound being selected from among ammonium molybdate, alkali molybdate and alkaline earth molybdate, ammonium vanadate, alkali vanadate and alkaline earth vanadate, ammonium zirconate, alkali zirconate and alkaline earth zirconate.
    Type: Grant
    Filed: January 7, 2010
    Date of Patent: October 2, 2012
    Assignee: Federal-Mogul Burscheid GmbH
    Inventors: Rudolf Linde, Stefan Durdoth
  • Publication number: 20100112376
    Abstract: A method of producing a structured hard chrome layer is described, wherein chromium is deposited from an electrolyte onto a workpiece, said electrolyte containing: (a) a Cr (VI) compound in an amount corresponding to 50 g/l to 600 g/l of chromic acid anhydride (b) 0.5 g/l to 10 g/l of sulphuric acid; (c) 1 g/l to 20 g/l of aliphatic sulphonic acid, comprising 1 to 6 carbon atoms, and (d) 10 g/l to 200 g/l of at least one compound forming a dense cathode film, said compound being selected from among ammonium molybdate, alkali molybdate and alkaline earth molybdate, ammonium vanadate, alkali vanadate and alkaline earth vanadate, ammonium zirconate, alkali zirconate and alkaline earth zirconate. Further, the application relates to a structured hard chrome layer obtained according to said method and to an electrolyte for carrying out said method.
    Type: Application
    Filed: January 7, 2010
    Publication date: May 6, 2010
    Applicant: FEDERAL-MOGUL BURSCHEID GMBH
    Inventors: Rudolf LINDE, Stefan DURDOTH
  • Patent number: 7699970
    Abstract: A method of producing a structured hard chrome layer is described, wherein chromium is deposited from an electrolyte onto a workpiece, said electrolyte containing: (a) a Cr (VI) compound in an amount corresponding to 50 g/l to 600 g/l of chromic acid anhydride (b) 0.5 g/l to 10 g/l of sulphuric acid; (c) 1 g/l to 20 g/l of aliphatic sulphonic acid, comprising 1 to 6 carbon atoms, and (d) 10 g/l to 200 g/l of at least one compound forming a dense cathode film, said compound being selected from among ammonium molybdate, alkali molybdate and alkaline earth molybdate, ammonium vanadate, alkali vanadate and alkaline earth vanadate, ammonium zirconate, alkali zirconate and alkaline earth zirconate. Further, the application relates to a structured hard chrome layer obtained according to said method and to an electrolyte for carrying out said method.
    Type: Grant
    Filed: September 18, 2003
    Date of Patent: April 20, 2010
    Assignee: Federal-Mogul Burscheid GmbH
    Inventors: Rudolf Linde, Stefan Durdoth
  • Publication number: 20080060945
    Abstract: A method for producing a structured hard chromium layer, during which chromium from an electrolyte is deposited onto a workpiece, which contains: a) a Cr(VI) compound in a quantity corresponding to between 50 and 300 g/l of chromic anhydride; b) 0.5 g/l to 10 g/l sulfuric acid, and; c) 5 g/l to 15 g/l aliphatic sulfonic acid having 1 to 6 carbon atoms. The electrolyte comprises substantially no compounds from the group consisting of ammonium molybdate, alkaline molybdate, alkaline earth molybdate, ammonium vanadate, alkaline vanadate and alkaline earth vanadate, ammonium zirconate, alkaline zirconate and alkaline earth zirconate, and is processed with a cathodic efficiency of 12% or less. A method for producing a coating, to a structured hard chromium layer, a coating and an electrolyte.
    Type: Application
    Filed: January 5, 2005
    Publication date: March 13, 2008
    Inventors: Rudolf Linde, Stefan Durdoth, Wolfgang Stuckert
  • Publication number: 20060054509
    Abstract: A method of producing a structured hard chrome layer is described, wherein chromium is deposited from an electrolyte onto a workpiece, said electrolyte containing: (a) a Cr (VI) compound in an amount corresponding to 50 g/l to 600 g/l of chromic acid anhydride (b) 0.5 g/l to 10 g/l of sulphuric acid; (c) 1 g/l to 20 g/l of aliphatic sulphonic acid, comprising 1 to 6 carbon atoms, and (d) 10 g/l to 200 g/l of at least one compound forming a dense cathode film, said compound being selected from among ammonium molybdate, alkali molybdate and alkaline earth molybdate, ammonium vanadate, alkali vanadate and alkali ne earth vanadate, ammonium zirconate, alkali zirconate and alkaline earth zirconate. Further, the application relates to a structured hard chrome layer obtained according to said method and to an electrolyte for carrying out said method.
    Type: Application
    Filed: September 18, 2003
    Publication date: March 16, 2006
    Inventors: Rudolf Linde, Stefan Durdoth