Patents by Inventor Helmut H. Frohlich

Helmut H. Frohlich 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: 5292622
    Abstract: A process for preparing images on a tonable, light-sensitive layer using a transfer layer containing at least 20 percent by weight of a toner and a polymer with a maximum tensile strength of at least 2 N/mm.sup.2 as a binder. The pigmented transfer layers can be used in color proofing processes requiring high resolution, reproducible color density and low dot gain.
    Type: Grant
    Filed: November 23, 1992
    Date of Patent: March 8, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Bernhard Metzger, Helmut H. Frohlich
  • Patent number: 5126226
    Abstract: A process for preparing images on a tonable, light-sensitive layer in which a transfer layer containing a toner and a core/shell polymer as a binder is used. The core polymer has a glass transition temperature above 50.degree. C. and the shell polymer has a glass transition temperature below 40.degree. C. Such transfer layers are used in proofing processes for high quality printing.
    Type: Grant
    Filed: December 3, 1990
    Date of Patent: June 30, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Helmut H. Frohlich, Michael Fryd
  • Patent number: 4902363
    Abstract: The invention relates to transfer layer sheets comprising a transfer layer on a compressible temporary support, and processes for their use.
    Type: Grant
    Filed: February 25, 1988
    Date of Patent: February 20, 1990
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: William E. Delaney, Helmut H. Frohlich
  • Patent number: 4806451
    Abstract: The invention relates to a process for producing an image on a light-sensitive tonable layer comprising the steps of:(A) exposing the light-sensitive layer imagewise to produce imagewise tacky and complementary non-tacky areas;(B) bringing the imagewise-exposed layer into surface-to-surface contact with a supported non-photosensitive transfer layer containing at least one finely divided powder and/or a dissolved dye in a binder; and(C) separating the transfer layer from the light-sensitive layer, whereby the transfer layer adheres selectively to the imagewise tacky areas,the improvement wherein, the binder of the transfer layer consists essentially of(a) about 55-97 wt. % of at least one polymer in the form of a powder having a minimum film-forming temperature of above 50.degree. C., and(b) about 3-45 wt.
    Type: Grant
    Filed: June 24, 1987
    Date of Patent: February 21, 1989
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Helmut H. Frohlich