Patents by Inventor Henning Erfurth

Henning Erfurth 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: 4084984
    Abstract: A temperature-stable inorganic yellow pigment of the composition Fe.sub.2 TiO.sub.5 .multidot. x TiO.sub.2, where x is from 0 to about 15, with a particle diameter of less than about 1 micron is produced by forming an aqueous suspension of at least one finely divided iron compound selected from the group consisting of iron oxide, iron oxide hydroxide, iron hydroxide and iron carbonate and at least one finely divided titanium compound selected from the group consisting of titanium dioxide and titanium dioxide oxide hydrate, the iron and titanium compounds being present in accordance with the stoichiometric composition Fe.sub.2 TiO.sub.5 .multidot. x TiO.sub.2 where x is from 0 to about 15, removing the aqueous phase from the mixed suspension, and calcining the residue at a temperature from about 600.degree. C to 1100.degree. C.
    Type: Grant
    Filed: August 14, 1974
    Date of Patent: April 18, 1978
    Assignee: Bayer Aktiengesellschaft
    Inventors: Franz Hund, Wilhelm Holznagel, Henning Erfurth, Friedrich Kindervater, Willi Hennings
  • Patent number: 4036662
    Abstract: In the production of temperature-stable inorganic pigment of pseudobrookite-titanium dioxide structure having the composition Fe.sub.2 TiO.sub.5.sup.. x TiO.sub.2, wherein x is from 0 to about 15, by preparing a suspension of finely divided titanium dioxide or titanium dioxide hydrate and at least one of finely divided iron oxide, iron oxide hydroxide, iron hydroxide and iron carbonate, removing the aqueous phase of the suspension from a solid residue and calcining the residue at a temperature in the range of about 600.degree. to 1100.degree.C, the improvement which comprises including in the suspension or in the solid residue at least one compound of a metal selected from the group consisting of lithium, sodium, potassium, magnesium, zinc, calcium, aluminum, copper, vanadium, chromium, manganese, cobalt and nickel, the compound being present in a quantity to provide about 0.1 to 10 % by weight of metal based on the pigment.
    Type: Grant
    Filed: October 20, 1975
    Date of Patent: July 19, 1977
    Assignee: Bayer Aktiengesellschaft
    Inventors: Jacob Rademachers, Henning Erfurth, Franz Hund
  • Patent number: 3983221
    Abstract: A process for the production of basic aluminum nitrate solutions by reacting metallic aluminum with nitric acid, comprising establishing a body of metallic aluminum, supplying additional aluminum to said body, supplying to said body countercurrent to the supply of the additional aluminum nitric acid of a concentration of about 5 to 30% by weight having basic aluminum nitrate dissolved therein and a pH of about 1 to 4, maintaining said body at a temperature of from about 30.degree.C up to the boiling point of the nitric acid, whereby the aluminum reacts with the nitric acid, and removing solution containing reaction product adjacent the point of supply of the additional aluminum and remote from the point of supply of the nitric acid.
    Type: Grant
    Filed: March 31, 1975
    Date of Patent: September 28, 1976
    Assignee: Bayer Aktiengesellschaft
    Inventors: Jakob Rademachers, Peter Woditsch, Henning Erfurth, Bernd Holle, Wilhelm Schnell