Patents by Inventor Wilhelm Sarnecki

Wilhelm Sarnecki 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: 4497723
    Abstract: A process for the preparation of acicular ferrimagnetic iron oxides by reducing gamma-iron(III) oxide hydroxide to magnetite, at from 280.degree. to 620.degree. C., by means of an organic compound which is decomposable at this temperature in the presence of iron oxide, and, optionally, a stream of reducing gas, and, if desired, then oxidizing the magnetite with oxygen-containing gases, at from 150.degree. to 450.degree. C., to acicular ferrimagnetic iron oxide of the formula FeO.sub.x, where x is from above 1.33 to 1.50, wherein the organic compound used for the reduction is a non-polar glycerol ester of a fatty acid which is introduced into the aqueous reaction suspension during the preparation of the gamma-iron(III) oxide hydroxide.
    Type: Grant
    Filed: June 27, 1983
    Date of Patent: February 5, 1985
    Assignee: BASF Aktiengesellschaft
    Inventors: Manfred Ohlinger, Guenter Vaeth, Peter Rudolf, Wilhelm Sarnecki, Helmut Jakusch, Eberhard Koester, Milena Melzer
  • Patent number: 4464352
    Abstract: A process for the manufacture of acicular ferrimagnetic iron oxide by converting acicular iron(III) oxide hydroxide at from 300.degree. to 650.degree. C., by treatment with an organic compound which decomposes in this temperature range in the presence of iron oxide, the iron(III) oxide hydroxide used for the reaction being a lepidocrocite which has been heat-treated at from 300.degree. to 700.degree. C.
    Type: Grant
    Filed: December 10, 1982
    Date of Patent: August 7, 1984
    Assignee: BASF Aktiengesellschaft
    Inventors: Horst Autzen, Herbert Motz, Peter Rudolf, Wilhelm Sarnecki, Werner Steck, Guenter Vaeth
  • Patent number: 4448761
    Abstract: Acicular ferrimagnetic iron oxides are prepared by a process in which iron (III) oxide hydroxide consisting essentially of lepidocrocite is reduced at from 350.degree. to 600.degree. C. by means of an organic compound which is a synthetic polymer with a molecular weight of from 3,000 to 40,000 to give magnetite, which, if desired, is subsequently partially or completely oxidized with an oxygen-containing gas at from 200.degree. to 450.degree. C.
    Type: Grant
    Filed: October 20, 1982
    Date of Patent: May 15, 1984
    Assignee: BASF Aktiengesellschaft
    Inventors: Wilhelm Sarnecki, Jenoe Kovacs, Werner Loeser, Peter Rudolf, Guenter Vaeth
  • Patent number: 4439231
    Abstract: Acicular ferromagnetic metal particles consisting essentially of iron are prepared by a process wherein acicular iron(III) oxide hydroxide provided with a shape-stabilizing surface coating, or iron(III) oxide obtained therefrom by dehydration, is reduced by means of a decomposable organic compound and hydrogen.
    Type: Grant
    Filed: July 28, 1983
    Date of Patent: March 27, 1984
    Assignee: BASF Aktiengesellschaft
    Inventors: Werner Steck, Peter Rudolf, Wilhelm Sarnecki, Werner Loeser, Jenoe Kovacs, Helmut Jakusch
  • Patent number: 4367214
    Abstract: A process for the manufacture of acicular ferrimagnetic iron oxide by heating iron(III) oxide or iron(III) oxide hydroxide at 220.degree.-460.degree. C. under a water vapor partial pressure of not less than 30 mbar, reducing the resulting product to magnetite by means of hydrogen and/or CO and/or an organic compound which can decompose in the presence of iron oxide, and then oxidizing the magnetite with an oxygen-containing gas to give acicular ferrimagnetic iron oxide of the formula FeO.sub.X, where X is from 1.33 to 1.50.
    Type: Grant
    Filed: July 31, 1980
    Date of Patent: January 4, 1983
    Assignee: BASF Aktiengesellschaft
    Inventors: Wilhelm Sarnecki, Laszlo Marosi, Horst Autzen, Manfred Ohlinger, Werner Steck
  • Patent number: 4360377
    Abstract: Ferromagnetic metal particles, consisting essentially of iron and comprising a core, containing not less than 85% by weight of metallic iron, and an iron oxide plus chromium oxide surface layer surrounding this core, which layer additionally contains one or more elements selected from the group comprising zinc, phosphorus in the form of phosphate, aluminum, calcium, strontium, barium, cadmium, lead, cobalt and nickel in a total amount of not more than 9.5% by weight, based on the total amount of the metal particles, and a process for the production of such particles.
    Type: Grant
    Filed: June 29, 1981
    Date of Patent: November 23, 1982
    Assignee: BASF Aktiengesellschaft
    Inventors: Werner Steck, Hermann Roller, Wilhelm Sarnecki, Werner Balz
  • Patent number: 4344791
    Abstract: A process for the manufacture of acicular ferromagnetic iron particles by heating a goethite, provided with a shape-stabilizing surface coating, at 250.degree.-450.degree. C. in an atmosphere containing water vapor at a partial pressure of not less than 30 mbar, to give alpha-iron(III) oxide, and reducing this material with hydrogen at 275.degree.-425.degree. C., and the use of the iron particles thus obtained as magnetic material in the production of magnetic recording media.
    Type: Grant
    Filed: July 31, 1980
    Date of Patent: August 17, 1982
    Assignee: BASF Aktiengesellschaft
    Inventors: Werner Steck, Wilhelm Sarnecki, Laszlo Marosi, Manfred Ohlinger, Werner Loeser
  • Patent number: 4295879
    Abstract: A process for the manufacture of acicular ferromagnetic iron particles by reducing an iron(III) oxide which carries a shape-stabilizing surface coating and has been produced by heating acicular iron(III) oxide hydroxide at 250.degree.-390.degree. C. in an atmosphere containing water vapor at a partial pressure of not less than 30 mbar, with hydrogen at 275.degree.-425.degree. C.
    Type: Grant
    Filed: July 31, 1980
    Date of Patent: October 20, 1981
    Assignee: BASF Aktiengesellschaft
    Inventors: Werner Steck, Wilhelm Sarnecki, Laszlo Marosi, Manfred Ohlinger, Horst Autzen
  • Patent number: 4259368
    Abstract: A process for the manufacture of acicular magnetic iron oxides which consist of a core of gamma-iron(III) oxide and a shell of a magnetite modified with zinc(II) ions and/or manganese(II) ions and which contain, based on the total modified gamma-iron(III) oxide, from 0.1 to 20 percent by weight of iron(II) ions, from 0.1 to 10 percent by weight of zinc(II) ions and/or from 0.1 to 10 percent by weight of manganese(II) ions.
    Type: Grant
    Filed: April 8, 1980
    Date of Patent: March 31, 1981
    Assignee: BASF Aktiengesellschaft
    Inventors: Peter Rudolf, Werner Steck, Wilhelm Sarnecki, Christof Jaeckh
  • Patent number: 4221776
    Abstract: A process for the manufacture of acicular ferrimagnetic iron oxide by reducing heat-treated acicular iron(III) oxide hydroxide with an organic compound which decomposes in the presence of iron oxide at from 450.degree. to 650.degree. C., followed by at least partial oxidation with an oxygen-containing gas at from 200.degree. to 500.degree. C., wherein the iron(III) oxide hydroxide employed is heat-treated at from 450.degree. to 700.degree. C. and has a surface area, measured by the BET method, of from 10 to 23 m.sup.2 /g.
    Type: Grant
    Filed: January 25, 1979
    Date of Patent: September 9, 1980
    Assignee: BASF Aktiengesellschaft
    Inventors: Horst Autzen, Helmut Jakusch, Eberhard Koester, Werner Loeser, Peter Rudolf, Wilhelm Sarnecki, Werner Steck
  • Patent number: 4213959
    Abstract: A process for the manufacture of acicular ferrimagnetic iron oxide by dehydrating acicular iron(III) oxide hydroxides to give acicular iron(III) oxides, then reducing these iron(III) oxides at from 300.degree. to 650.degree. C. by means of an organic compound which decomposes in this temperature range, and oxidizing the reduced product with an oxygen-containing gas at from 200.degree. to 500.degree. C., wherein the acicular iron(III) oxide hydroxides employed consist of a mixture of goethite and lepidocrocite, containing at least 60% of the latter, and the dehydration is carried out at from 250.degree. to 700.degree. C.
    Type: Grant
    Filed: August 3, 1978
    Date of Patent: July 22, 1980
    Assignee: BASF Aktiengesellschaft
    Inventors: Rudolf Brodt, Helmut Jakusch, Eberhard Koester, Werner Loeser, Manfred Ohlinger, Wilhelm Sarnecki, Werner Steck
  • Patent number: 4178171
    Abstract: A process for the manufacture of acicular ferromagnetic iron particles by reducing acicular iron(III) oxide hydroxides which consist of pure synthetic lepidocrocite or a mixture of synthetic goethite and at least 70% by weight of synthetic lepidocrocite.The iron(III) oxide hydroxides used carry, on their surface, an alkaline earth metal cation and an anion of a monobasic, dibasic or tribasic aliphatic carboxylic acid of up to 6 carbon atoms or an organic compound containing at least two groups capable of chelating the alkaline earth metal cation, and are produced in such a way that they consist of at least 70 percent by weight of lepidocrocite and have a length-to-width ratio of not less than 15:1.Reduction of such iron(III) oxide hydroxides gives iron particles with pronounced shape anisotropy, which exhibit both good magnetic properties and a narrow field strength distribution.
    Type: Grant
    Filed: March 20, 1978
    Date of Patent: December 11, 1979
    Assignee: BASF Aktiengesellschaft
    Inventors: Werner Steck, Rudolf Brodt, Wilhelm Sarnecki, Helmut Jakusch, Manfred Ohlinger, Eberhard Koester