Patents by Inventor Roman Keiper

Roman Keiper 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: 5328797
    Abstract: The present invention relates to a process for producing a negative-working photosensitive lithographic printing form, in which a negative-working photosensitive mixture which is dissolved in a solvent mixture and which contains a negative-working photosensitive compound and a polymeric binder which is insoluble in water but soluble in aqueous alkaline solution is applied to a base and the layer obtained is subsequently dried, which process comprises using a mixture of more than 2% by weight of at least one monoether of diethylene glycol with one or more organic solvent(s) having a boiling point below 200.degree. C. as the solvent mixture.
    Type: Grant
    Filed: December 23, 1992
    Date of Patent: July 12, 1994
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Rudolf Neubauer, Roman Keiper, Siegfried Nuernberger, Sabine Pilger
  • Patent number: 4801508
    Abstract: The invention discloses a drafting material which comprises a plastic support having, on at least one surface, an adhesive layer, a layer of a pigmented or clear lacquer and an antistatic top layer, in which the layer of pigmented or clear lacquer contains a combination of(a) a linear aromatic polyester,(b) a carboxylated acrylate resin,(c) a cyclic acid amide, corresponding to the general formula I ##STR1## wherein R stands for an alkyl group having 1 to 4 carbon atoms, and (d) an acid catalyst.In the drafting material of the invention hardness, and resistance to solvents are improved.
    Type: Grant
    Filed: June 23, 1987
    Date of Patent: January 31, 1989
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Walter Lutz, Roman Keiper
  • Patent number: 4576981
    Abstract: The invention relates to an adhesive composition which is suitable for use on a shaped part of polyester, in particular a polyester film, and comprises a copolyester, optionally in combination with light-sensitive substances, fillers and pigments, whereby the copolyester additionally contains at least one copolymer of vinylidene chloride, preferably in a weight ratio of about 3:1 to 1:1. The adhesive composition can furthermore contain cellulose acyl esters, such as low molecular-weight cellulose acetobutyrate or cellulose propionate. Polybasic oxycarboxylic acids and levelling agents can also be present. The adhesive composition can be employed in mixtures with, for example, light-sensitive lacquer systems.
    Type: Grant
    Filed: April 25, 1984
    Date of Patent: March 18, 1986
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Manfred Hilger, Gunter Hultzsch, Roman Keiper