Patents by Inventor Gerhard Schröder

Gerhard Schröder 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: 4290799
    Abstract: A metal powder, suitable for magnetic recording, consisting essentially of iron, the individual particles being acicular and containing on average no more then 5 pores and consisting on average of no more than 2 metal cores is produced by precipitating and oxidizing an aqueous iron-(II)-salt solution to produce finely divided acicular iron-(III)-oxide-hydroxide, stabilizing it as by treatment with cadmium, lead, calcium, magnesium, zinc, aluminum, chromium, tungsten, a phosphorus oxide and/or a boron oxide, converting it into ferromagnetic iron oxide of low pore content, and reducing it to metallic iron with a gaseous reducing agent at about 300.degree. to 600.degree. C.
    Type: Grant
    Filed: February 25, 1980
    Date of Patent: September 22, 1981
    Assignee: Bayer Aktiengesellschaft
    Inventors: Gerhard Schroeder, Gunter Buxbaum, Franz Hund, Heinrich-Christian Schopper, Rolf Naumann
  • Patent number: 4264462
    Abstract: A finely divided magnetite pigment such as is used in magnetic tapes is stabilized against oxidation by contact with a heterocyclic nitrogen compound such as morpholine, triazole, piperazine or substitution products thereof. The heterocyclic compound can be applied as a solution or in vapor form.
    Type: Grant
    Filed: September 21, 1978
    Date of Patent: April 28, 1981
    Assignee: Bayer Aktiengesellschaft
    Inventors: Gunter Buxbaum, Bernd Stephan, Franz Hund, Gerhard Schroeder