Patents by Inventor Wolfgang Rambold

Wolfgang Rambold 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: 4921542
    Abstract: Iron oxide black pigments useful as coloring pigments for lacquers and plastics are prepared by an improved process wherein finely divided iron oxide black suspensions obtained from the precipitation processor the aniline process are filtered, washed, dried and ground with the improvement in the process comprising grinding the dried iron oxide pigment in a jet mill with air as the grinding medium and with a water content of from about 1 to 6% by weight based on the iron oxide black pigment input to the process.
    Type: Grant
    Filed: September 28, 1988
    Date of Patent: May 1, 1990
    Assignee: Bayer Aktiengesellschaft
    Inventors: Jakob Rademachers, Karl-Werner Ganter, Wolfgang Rambold, Gunter Linde
  • Patent number: 4492600
    Abstract: This invention relates to corrosion-inhibiting paints and lacquers containing pigments comprising an organic corrosion inhibitor intercalated into an inorganic matrix said pigment having the formula wherein ##EQU1## wherein Me(II)O is at least one divalent metal oxide;Me(III).sub.2 O.sub.3 is at least one trivalent metal oxide;A is at least one inorganic acid anhydride;I is at least one organic corrosion inhibitor;aq is from 0.5 to 9 moles of water; andx, y and z are whole or fractional numbers andx has a value of from 0 to 1,y has a value of from 0 to 0.7 andz has a value of from greater than 0 to 0.4,with the proviso that the organic corrosion inhibitor is at least 0.5% by weight of inorganic material a process for the production of these pigments and their use in paints, lacquers and lubricants.
    Type: Grant
    Filed: July 14, 1982
    Date of Patent: January 8, 1985
    Assignee: Bayer Aktiengesellschaft
    Inventors: Horst Brunn, Franz Hund, Wolfgang Rambold, Peter Kresse, Gerd von Szadkowski
  • Patent number: 4470844
    Abstract: Spherical agglomerates of surface-stabilized primary particles substantially consisting of iron, having a BET surface of about 5 to 50 m.sup.2 /g, measured on the agglomerate, in non-pyrophoric form and having a bulk density of about 0.5 to 2.0 kg/l and an agglomerate diameter of about 0.5 to 10 mm are produced by(a) reducing in dry phase particles consisting essentially of iron oxide,(b) intensively dispersing the particles in liquid phase,(c) coating the particles with an inorganic and/or organic coating optionally containing corrosion inhibitors,(d) separating the particles from the liquid phase by evaporating the volatile components with a continuously rotating and simultaneously tumbling movement, and(e) subjecting the resulting granulates to a thermal treatment. The particles are especially useful for the production of magnetic recording media.
    Type: Grant
    Filed: November 25, 1981
    Date of Patent: September 11, 1984
    Assignee: Bayer Aktiengesellschaft
    Inventors: Jakob Rademachers, Rolf Naumann, Hans-Peter Biermann, Gunter Buxbaum, Wolfgang Rambold
  • Patent number: 4443264
    Abstract: A zinc ferrite pigment comprising, by weight, about 99.8 to 90% of ZnFe.sub.2 O.sub.4 and about 0.2 to 10% of the component system (1-x)Al.sub.2 O.sub.3 and xP.sub.2 O.sub.5 wherein 0<x<1 is produced by calcining a suitable mixture of compounds. The resulting pigments are of high color quality and are substantially halogen-free, rendering them especially useful industrially even as anti-corrosion pigments.
    Type: Grant
    Filed: August 30, 1982
    Date of Patent: April 17, 1984
    Assignee: Bayer Aktiengesellschaft
    Inventors: Franz Hund, Willi Hennings, Horst Brunn, Peter Kresse, Wolfgang Rambold
  • Patent number: 4378252
    Abstract: A process for increasing the color purity of iron oxide pigment particles admixed with color-modifying impurities and obtained by the Penniman process or the aniline process, comprising introducing the particles into a magnetic field, and removing from the magnetic field two fractions of different magnetizability, the first fraction being iron oxide pigment particles of increased color purity and the second fraction being enriched in impurities.
    Type: Grant
    Filed: May 29, 1981
    Date of Patent: March 29, 1983
    Assignee: Bayer Aktiengesellschaft
    Inventors: Peter Kiemle, Franz Hund, Ingo Pflugmacher, Wolfgang Rambold
  • Patent number: 4235862
    Abstract: A process for the production of low sulphur chromium(III) oxide comprising annealing at a calcining temperature from about 800.degree. C. to 1100.degree. C. a mixture of alkali metal chromate and about 0.7 to 0.96 times its molar amount of ammonium sulfate, and separating the chromium(III) oxide formed from the alkali metal salt. Advantageously the ammonium sulfate in the form of a concentrated solution is mixed with solid alkali metal dichromate and the mixture thereafter is adjusted prior to calcination to a water concentration of less than about 15% by weight of water.
    Type: Grant
    Filed: December 11, 1978
    Date of Patent: November 25, 1980
    Assignee: Bayer Aktiengesellschaft
    Inventors: Wolfgang Rambold, Heinrich Heine, Bruno Raederscheidt, Gerhard Trenczek
  • Patent number: 4067747
    Abstract: A process for the production of chromium oxide green pigment comprising heating a mixture of ammonium dichromate with at least the stoichiometrically equivalent quantity of a sodium salt selected from the group consisting of chloride and sulfate over a period of at most about 15 minutes to a pigment-forming temperature of about 800 to 1100.degree. C in the presence of about 1 to 45% water based on the weight of the mixture, calcining the mixture at a temperature in the above-mentioned range, and separating the formed pigment from the salts. The mixture may be formed in situ by reaction of sodium dichromate with ammonium chloride or sulfate in the presence of water. The presence during calcining of organic modifiers such as sawdust or of boron compounds such as borax increases, tinting strength and disproportionately affect color. The pigments are brighter, and of higher tinting strength than heretofore produced.
    Type: Grant
    Filed: February 6, 1976
    Date of Patent: January 10, 1978
    Assignee: Bayer Aktiengesellschaft
    Inventors: Manfred Mansmann, Wolfgang Rambold
  • Patent number: 4040860
    Abstract: In the production of chromium oxide green pigment by heating a substantially stoichiometrically equivalent mixture of sodium dichromate dihydrate and an ammonium salt selected from the group consisting of the sulfate and chloride, the improvement which comprises dry mixing sodium dichromate dihydrate having a particle size less than 2 mm with the ammonium salt having a particle size less than about 0.5 mm, heating the resulting mixture over a period of about 15 minutes to a pigment-forming temperature of about 800.degree. to 1100.degree. C, calcining the mixture at a temperature in that range, and separating the formed pigment from the salts. To the mixture prior to heating there may be added sodium hydroxide solution, boron compounds such as borax and/or organic modifiers such as sawdust which improve the color and tinting strength of the resulting pigment. The pigments are brighter, and of higher tinting strength than heretofore produced.
    Type: Grant
    Filed: February 6, 1976
    Date of Patent: August 9, 1977
    Assignee: Bayer Aktiengesellschaft
    Inventors: Manfred Mansmann, Wolfgang Rambold