Patents Assigned to The Yomiuri Shimbun
  • Patent number: 3931762
    Abstract: When a thermoplastic resin sheet such as polyethylene, polypropylene, polystyrene, ABS or polyvinyl chloride resin sheet which contains 0 - 80 % by weight of an inorganic filler and has a foaming ratio (a) of 1 or 1 < a .ltoreq. 4 and which satisfies the relation 130 .gtoreq. 20a + b .gtoreq. 30 (wherein "a" is the foaming ratio and "b" is amount of the inorganic filler) is pressed onto a matrix in such a manner that the thickness of said resin sheet before pressing is larger than the thickness of the convex portions of the resultant resin relief plate, thus obtained relief plate has excellent printability.
    Type: Grant
    Filed: December 14, 1973
    Date of Patent: January 13, 1976
    Assignees: Sumitomo Chemical Company, Limited, The Yomiuri Shimbun
    Inventors: Nobuo Fukushima, Masakazu Inoue, Ryouzo Takai, Kozo Hotta