Patents Assigned to Nippon Zeon Company Limited
  • Patent number: 5162380
    Abstract: Foamed articles of polyvinyl chloride resins are prepared by mixing an organic foaming agent having a temperature of foaming by decomposition of 100.degree. C. or above and a plasticizer with a polyvinyl chloride resin containing epoxy group which is formed into particles having an average diameter in the range from 0.05 to 5 .mu.m and has a concentration of the epoxy group at the surface of the particle of 1.times.10.sup.-2 weight % or more and a concentration of the total epoxy group in the particles of the said resin of 10 weight % or less at a temperature where the organic foaming agent does not decompose and coating or molding the mixed compound with foaming by heating.Foamed articles of polyvinyl chloride resins having excellent physical properties and high expansion ratios can be prepared without utilizing a crosslinking agent at the ambient pressure.
    Type: Grant
    Filed: April 24, 1992
    Date of Patent: November 10, 1992
    Assignee: Nippon Zeon Company Limited
    Inventors: Toshihiko Hori, Kazunori Ueki