Patents Examined by David Welsch
  • Patent number: 5043237
    Abstract: Photohardenable electrostatic master with improved environmental latitude and dot shape comprising(1) an electrically conductive substrate, and coated thereon(2) a layer of photohardenable composition having a speed that requires an exposure energy in the range of 3 to 90 mjoules/sq. cm. consisting essentially of(a) at least two incompatible organic polymeric binders,(b) at least one monomeric compound having at least ethylenically unsaturated group, and(c) a photoinitiator or photoinitiator system that activates polymerization of the ethylenically unsaturated monomer upon exposure to actinic radiation,(d) a chain transfer agent, and(e) at least one polymerization inhibitor in an amount of at least 0.1% by weight based on the total weight of photohardenable composition.A xeroprinting process is described using the master. The master is used in graphic arts, color proofing which duplicates images produced by printing, preparation of printed circuit boards, resists, soldermasks, etc.
    Type: Grant
    Filed: January 12, 1990
    Date of Patent: August 27, 1991
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Graciela B. Blanchet-Fincher, Catherine Teh-Lin Chang