Patents Assigned to Kabushikikaisha Asahi Shinbunsha
  • Patent number: 4297263
    Abstract: A method of making a polypropylene printing plate using a paper matrix in which a roll and an opposing member are prepared, a paper matrix is attached to one of the roll and opposing member, a crystalline ethylene-propylene copolymer having a MFI (melt flow index) of 3.about.10, containing ethylene less than 20% by weight and tensile yield strength of 220.about.330 kg/cm.sup.2 is continuously fed under molten state between the roll and the opposing member, and then the crystalline ethylene-propylene copolymer is pressed and cooled to be hardened.Further, a reproducing printing plates consists of a crystalline ethylene-propylene copolymer whose melt flow index is selected in a range of 3.about.10, which contains ethylene less than 20 weight % and which has the tensile yield strength of 220.about.330 kg/cm.sup.2.
    Type: Grant
    Filed: March 24, 1976
    Date of Patent: October 27, 1981
    Assignees: Mitsui Toatsu Chemicals Inc., Kabushikikaisha Asahi Shinbunsha
    Inventors: Kinzo Miyamoto, Takayasu Tanaka, Yoshimi Inoue