Patents by Inventor Bernd Dewald

Bernd Dewald 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).

  • Polymer laminates having increased hiding power
    Patent number: 6143379
    Abstract: A polymer laminate essentially consisting of at least two cholesteric, liquid-crystalline polymer layers and a light-absorbent layer in between is suitable as starting material for effect pigments having a color impression which is dependent on the viewing angle.
    Type: Grant
    Filed: April 16, 1998
    Date of Patent: November 7, 2000
    Assignee: Clariant GmbH
    Inventors: Axel Schoenfeld, Bernd Dewald
  • Colored cholesteric liquid-crystal polymers having optically variable properties
    Patent number: 6017984
    Abstract: The invention relates to colorant compositions consisting essentially of one or more cholesteric liquid-crystalline polymers and at least one colorant which absorbs light in the visible wavelength range. Suitable colorants are organic or inorganic pigments or dyes. Coatings comprising such colorant compositions feature color effects which are dependent on the viewing angle and which cannot be obtained by means of absorption pigments alone or by means of cLCP effect coatings.
    Type: Grant
    Filed: October 16, 1997
    Date of Patent: January 25, 2000
    Assignee: Clariant GmbH
    Inventors: Axel Schonfeld, Erwin Dietz, Bernd Dewald
  • Colorant formulation
    Patent number: 4782111
    Abstract: A colorant formulation is described for mass-coloring high-melting polyesters. It comprises colorant and support for the colorant. The colorant formulation has a recrystallization exotherm of 8 to 55 joule/g between 210.degree. C. and 150.degree. C.
    Type: Grant
    Filed: December 5, 1986
    Date of Patent: November 1, 1988
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Peter Klein, Bernd Dewald, Wolfgang Teige
  • Dyeing agent compositions based on polypropylene wax
    Patent number: 4235641
    Abstract: Preparations of insoluble colorants, especially pigments, are obtained by distributing the colorant in molten polypropylene wax having a viscosity of 0.5 to 5 Pa.s, determined at 170.degree. C., and an isotactic proportion of 40 to 90% by weight. These preparations are easily dispersible in polyolefins and especially useful for dyeing polypropylene in the mass.
    Type: Grant
    Filed: June 28, 1979
    Date of Patent: November 25, 1980
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Manfred Engelmann, Karl Maier, Arno Spange, Bernd Dewald, Hans-Joachim Lenz, Wolfgang Teige