Patents Assigned to High Tech Chem Co., Ltd.
  • Patent number: 6448312
    Abstract: A colored resin composition for water pipes which comprises (A) a polyethylene resin and (B) specific amounts of (i) a cobalt blue pigment, (ii) at least one selected from phthalocyanine pigments having no metals and metal phthalocyanine pigments having no chlorine atoms or one chlorine atom in a molecule, (iii) a dioxazine pigment and (iv) a titanium dioxide pigment and a colored water pipe which comprises the colored polyethylene resin composition and has a color tone within a specific color solid expressed by the values of the Munsell standard color table before and after the test of resistance to chlorine water for 500 hours. The composition and the water pipe are colored in a bluish color and exhibits an excellent hiding property, excellent fastness of the color tone of the coloring component to water containing chlorine and an excellent property for preventing formation of blisters in water containing chlorine.
    Type: Grant
    Filed: October 11, 2001
    Date of Patent: September 10, 2002
    Assignees: High Tech Chem Co., Ltd., Japan Polyolefins Co., Ltd.
    Inventors: Kotaro Oshima, Tohru Matsuoka, Yozo Nagai, Mitsuo Nakamura