Patents by Inventor Reinhard Kraetschmer

Reinhard Kraetschmer 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: 5601647
    Abstract: An improved extrusion coater having at least two coater slots for applying one or more magnetizable layers to a flexible nonmagnetic substrate is described. The upper lip of the outlet orifice is recessed relative to the lower lip and, in addition, the edge of a right parallelepiped magnet which has a gradient of more than 400 A/cm.sup.2 in the direction of the extruder slot, resulting in a stabilized liquid cushion, is arranged opposite the outlet orifice for the dispersions from the extrusion coater, on the other side of the substrate. It is thus possible to apply very thin layers and to make the meniscus insensitive to interfering forces. To reduce the edge bead, a stripping plate (13) which is extended beyond the range of the upper or lower lip of the extrusion coater, in the direction of the coated material web (1), is mounted at both coating edges, a minimum distance of from 0.05 to 0.8 mm between the surface (19) of the stripping plate (13) and the coated material web being established (FIG. 1).
    Type: Grant
    Filed: February 1, 1995
    Date of Patent: February 11, 1997
    Assignee: BASF Magnetics GmbH
    Inventors: Albert Pertzsch, Reinhard Kraetschmer, Michael Breitsameter, Siegfried Rieger
  • Patent number: 5466542
    Abstract: A wet-on-wet application process by means of a sheet extruder having at least two slot dies is described, the upper layer containing metal powders and/or metal powder alloys while the lower layer contains the same magnetic pigments and conductivity-increasing and/or transparency-reducing additives, preferably carbon black, and both layers having virtually the same rheological properties. The magnetic recording medium has improved conductivity and very good running behavior, in particular when used as a mirror mastertape.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: November 14, 1995
    Assignee: BASF Magnetics GmbH
    Inventors: Reinhard Kraetschmer, Albert Pertzsch, Josef Schelble
  • Patent number: 5422137
    Abstract: A wet-on-wet application process by means of an extrusion coater having at least two slot dies is described, the upper lip of the common outlet orifice of the slot dies being recessed relative to the lower lip and a right parallelepiped magnet whose upper edge is opposite the extruder orifice at a distance of, preferably, from 1 to 1.5 mm away being arranged on the other side of the nonmagnetic substrate and parallel to the latter, in which the uppermost layer contains magnetic pigments and has a layer thickness of more than 2.0 .mu.m while the lower layer is nonmagnetic, may contain a conductivity-increasing additive or nonmagnetic fillers and has a thickness of less than 0.5 .mu.m when dry. The magnetic recording medium has very good mechanical and electroacoustic properties, improved conductivity, very good adhesion, improved surface quality and a smaller number of dropouts.
    Type: Grant
    Filed: October 13, 1993
    Date of Patent: June 6, 1995
    Assignee: BASF Magnetics GmbH
    Inventors: Gerhard Huebler, Wolf-Dieter Schroeer, Reinhard Kraetschmer, Josef Schelble