Patents by Inventor Johannes G. C. M. deBres

Johannes G. C. M. deBres 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: 4384012
    Abstract: A magnetic recording element with a carrier and a magnetic coating which comprises a magnetic pigment dispersed in a binder in which the sulphate ions present on the surface of the pigment particles are bound in the form of a water-insoluble salt, as well as methods of manufacturing the magnetic recording element in which the magnetic pigment or a non-magnetic FeOOH pigment from which the magnetic pigment can be manufactured is treated with an aqueous solution of a water-soluble salt the cations of which form water-insoluble salts with the sulphate ions present on the surface of the pigment particles and the treated pigment is then processed according to known methods to a magnetic recording element or in which the above-mentioned salt is mixed with the ingredients of the magnetic coating and the resulting magnetic coating lacquer is provided on a carrier and dried.
    Type: Grant
    Filed: December 14, 1981
    Date of Patent: May 17, 1983
    Assignee: U.S. Philips Corporation
    Inventors: Hendrikus F. Huisman, Johannes G. C. M. deBres