Patents by Inventor Dieter Schaefer

Dieter Schaefer 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: 4003336
    Abstract: A device for manufacturing magnetic recording media in which the magnetic particles in the recording layer are oriented in a preferred direction, the fluid coating applied to the base being subjected to the action of a magnetic field produced in the air gaps between the spaced apart poles of two magnetic circuits, one on each side of the coated face, arranged symmetrically with respect to the plane of the coated base, the edges of the poles adjacent to the coated base terminating in screening elements shaped in such a way that the distance between the surfaces of the screening elements facing the coated base and the coated base itself increases as the screening elements extend away from the edges of the poles. A high degree of magnetic anisotropy in the recording layer can also be obtained when the magnetic circuits are at a relatively large distance from the still fluid magnetic coating.
    Type: Grant
    Filed: August 13, 1975
    Date of Patent: January 18, 1977
    Assignee: BASF Aktiengesellschaft
    Inventors: Eberhard Koester, Paul Deigner, Roland Falk, Karl Uhl, Dieter Schaefer
  • Patent number: 4001463
    Abstract: A process and apparatus for the manufacture of magnetic discs in which the preferred direction of particle orientation is parallel to the plane of the disc and tangential to its circumference. The base discs coated with the still fluid magnetic dispersion, are introduced into a zone of magnetic flux bounded by conductors, the conducting boundary being so arranged that the current flow on one side of the base disc runs radially outwards and on the other side runs radially inwards.
    Type: Grant
    Filed: July 21, 1975
    Date of Patent: January 4, 1977
    Assignee: BASF Aktiengesellschaft
    Inventors: Dieter Schaefer, Herbert Motz
  • Patent number: 3996407
    Abstract: Magnetic recording media comprising a non-magnetizable flexible base and a firmly adhering magnetic coating based on a dispersion, containing a silane, of a magnetic pigment in a polymeric binder, and a process for their manufacture. The silane is an aminoalkylsilane R.sub.n Si(OR').sub.4-n, wherein n is 1, 2 or 3, R' is alkyl of 1 to 8 carbon atoms and R is aminoalkyl of the formula with one or more primary and/or secondary amino groups and from 3 to 11 carbon atoms. Magnetic recording media comprising a magnetic coating containing such a silane exhibit better abrasion resistance and better electromagnetic properties than comparable coatings.
    Type: Grant
    Filed: December 18, 1974
    Date of Patent: December 7, 1976
    Assignee: BASF Aktiengesellschaft
    Inventors: Egon Von Gross, Heinz Stritzinger, Job-Werner Hartmann, Manfred Steuerwald, Ursula Klein, Dieter Schaefer
  • Patent number: 3959553
    Abstract: The invention relates to magnetic discs in which first a non-magnetic intermediate layer and then the magnetic coating are applied by conventional methods to an aluminum disc. The intermediate layer applied to the non-magnetic metallic carrier disc is a hard non-magnetic coating which can be polished and which consists of a dispersion of a pulverulent mixture of finely divided inorganic non-magnetic pigments having a Mohs' hardness of at least 7 in a binder which can be cured and which provides firm cohesion of the pigment particles and good adhesion thereof to the non-magnetic base disc, the pigment mixture containing at least 3 percent by weight of corundum powder having a particle size of from about 1 to 20.mu.u. Magnetic discs with very thin magnetic coatings which possess good magnetic and mechanical properties and whose thickness varies only minimally are thus produced in a simple manner.
    Type: Grant
    Filed: November 9, 1973
    Date of Patent: May 25, 1976
    Assignee: BASF Aktiengesellschaft
    Inventors: Job Werner Hartmann, Werner Ostertag, Rudolf Sand, Dieter Schaefer, Hans Joerg Hartmann