Patents by Inventor Wolfgang Oehlert

Wolfgang Oehlert 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).

  • Production of red iron oxide pigment
    Patent number: 10221326
    Abstract: The present invention relates to an improved process for producing red iron oxide pigments by the Penniman process with nitrate (also called nitrate process or direct red process) and to apparatus for implementing this process, and also to the use of the plant for producing red iron oxide pigments by the Penniman process with nitrate.
    Type: Grant
    Filed: November 8, 2013
    Date of Patent: March 5, 2019
    Assignee: LANXESS Deutschland GmbH
    Inventors: Waldemar Czaplik, Juergen Kischkewitz, Wolfgang Oehlert, Huajun Li
  • PRODUCTION OF RED IRON OXIDE PIGMENT
    Publication number: 20160272836
    Abstract: The present invention relates to an improved process for producing red iron oxide pigments by the Penniman process with nitrate (also called nitrate process or direct red process) and to apparatus for implementing this process, and also to the use of the plant for producing red iron oxide pigments by the Penniman process with nitrate.
    Type: Application
    Filed: November 8, 2013
    Publication date: September 22, 2016
    Inventors: Waldemar CZAPLIK, Juergen KISCHKEWITZ, Wolfgang OEHLERT, Huajun LI
  • Heat-stable zinc ferrite colour pigments, process for preparing them and their use
    Patent number: 7294192
    Abstract: The present invention relates to zinc ferrite colour pigments, including a process for preparing and using them and, more particularly, the present invention relates to light-coloured zinc ferrite colour pigments having enhanced thermal stability, a magnesium content of from 0.01%-0.4% by weight, a color difference ?E* according to DIN 53 772 at 260° C. of <3.0, a color difference ?E* according to DIN 53 772 at 300° C. of <5.0, and a lightness of L*, measured in PE-HD full shade according to DIN 55 772 of >52.5.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: November 13, 2007
    Assignee: LANXESS Deutschland GmbH
    Inventors: Carsten Rosenhahn, Horst Brunn, Wolfgang Oehlert
  • Heat-stable zinc ferrite colour pigments, process for preparing them and their use
    Publication number: 20050087106
    Abstract: The present invention relates to zinc ferrite colour pigments, to a process for preparing them and to their use. It relates in particular to light-coloured zinc ferrite colour pigments having enhanced thermal stability.
    Type: Application
    Filed: October 21, 2004
    Publication date: April 28, 2005
    Inventors: Carsten Rosenhahn, Horst Brunn, Wolfgang Oehlert
  • Heat-stable iron oxide yellow pigments
    Patent number: 6117228
    Abstract: Pure-coloured iron oxide yellow pigments having a silking index of less than 5 and a heat resistance of greater than 220.degree. C. in polyethylene for at least 5 minutes are obtained by oxidation of metallic iron with nitrobenzene in an acid medium in the presence of compounds of elements chosen from main groups 3 and 4 of the periodic table.
    Type: Grant
    Filed: November 16, 1998
    Date of Patent: September 12, 2000
    Assignee: Bayer AG
    Inventors: Wilfried Burow, Wolfgang Oehlert
  • Use of synthetic, iron raw materials for preparing iron oxide pigments
    Patent number: 6086846
    Abstract: The invention relates to the use of synthetic (synthetically produced) iron raw materials to prepare iron oxide pigments in the Penniman process and other iron-dissolution processes.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: July 11, 2000
    Assignee: Bayer AG
    Inventors: Wilfried Burow, Wolfgang Oehlert, Ulrike Pitzer, Heribert Bade
  • Use of synthetic, iron raw materials for preparing iron oxide pigments
    Patent number: 5837216
    Abstract: The invention relates to the use of synthetic (synthetically produced) iron raw materials to prepare iron oxide pigments in the Penniman process and other iron-dissolution processes.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: November 17, 1998
    Assignee: Bayer AG
    Inventors: Wilfried Burow, Wolfgang Oehlert, Ulrike Pitzer, Heribert Bade
  • Use of synthetic, bainite-rich iron raw materials for preparing iron oxide pigments
    Patent number: 5730794
    Abstract: The invention relates to the use of synthetically produced, bainite-rich iron raw materials to prepare iron oxide pigments.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: March 24, 1998
    Assignee: Bayer AG
    Inventors: Wilfried Burow, Wolfgang Oehlert, Bernd Iskluth
  • Thermally stable iron oxide pigments, a process for their preparation and their use
    Patent number: 5667579
    Abstract: The present invention relates to iron oxide pigments with an Fe(II) content of at least 5 wt. %, calculated as FeO, which have at least one inorganic after-treatment layer and at least one organic after-treatment coating, a process for preparing these iron oxide pigments and their use.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: September 16, 1997
    Assignee: Bayer AG
    Inventors: Wolfgang Oehlert, Friedrich Jonas, Gunter Buxbaum
  • Clean color shade, yellow-tinged red iron oxide pigments, and a process for their manufacture, and their use
    Patent number: 5665157
    Abstract: The invention relates to clean color shade, yellow-tinged red iron oxide pigments, and a process for their manufacture, and their use.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: September 9, 1997
    Assignee: Bayer AG
    Inventors: Wolfgang Oehlert, Wilfried Burow, Horst Brunn, Herbert Kunstmann