Self-adhesive carbonaceous grains and process for producing high-density and high-strength carbon artifacts showing a fine mosaic texture of optical anisotropy derived from such grains

• US 5,484,520 A
• Filed: 12/07/1994
• Issued: 01/16/1996
• Est. Priority Date: 12/09/1993
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Gas Chemical Company Incorporated (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Gas Chemical Company Incorporated (Mitsubishi Electric Corporation)
• Inventors: Kojima, Takashi, Sakamoto, Hitoshi, Mochida, Isao, Fujiura, Ryuji
• Primary Examiner(s): Straub, Gary P.
• Assistant Examiner(s): Hendrickson, Stuart L.
• Application Number:
  US08/350,679
• Time in Patent Office: 405 Days
• Field of Search: 423/445 R, 208/22, 208/39
• US Class Current: 208/22
• CPC Class Codes: C04B 35/528 obtained from carbonaceous particles with or without other non-organic components
• CPC Class Codes: C10C 3/00 Working-up pitch, asphalt, bitumen compositions of asphalts and other bitumenous materials C08L95/00

Abstract

Self-adhesive carbonaceous grains for use in the manufacture of high-density and high-strength carbon artifacts containing 0.5-1.5 wt % of a quinoline-soluble but pyridine-insoluble component and at least 97 wt % of a quinoline-insoluble component and which are prepared by heat-treating in a nonoxidizing atmosphere a mesophase pitch that is obtained by polymerizing condensed polycyclic hydrocarbons or substances containing them in the presence of a superacid consisting of hydrogen fluoride and boron trifluoride. The carbonaceous grains are molded and the mold is baked at a sufficient temperature to achieve its carbonization, with the heating rate being not more than 20° C./h in the temperature range from 400° to 600° C. In this way, high-density and high-strength carbon artifacts showing a homogeneous fine mosaic texture of optical anisotropy can be efficiently manufactured in high carbon yield.

Claims

1. Self-adhesive carbonaceous grains that contain 0.5-1.5 wt % of a quinoline-soluble but pyridine-insoluble component and at least 97 wt % of a quinoline-insoluble component and which is prepared by the heat treatment in a nonoxidizing atmosphere of a mesophase pitch that is obtained by polymerizing a condensed polycyclic hydrocarbon or a substance containing the same in the presence of hydrogen fluoride and boron trifluoride.

2. Carbonaceous grains according to claim 1 wherein the quinoline-soluble but pyridine-insoluble component is present in an amount of 0.7-1.3 wt % and the quinoline-insoluble component in an amount of at least 98 wt %.

3. Carbonaceous grains according to claim 1 wherein the condensed polycyclic hydrocarbon is selected from the group consisting of naphthalene, methylnaphthalene, anthracene, phenanthrene, acenaphthene, acenaphthylene and pyrene.

4. Carbonaceous grains according to claim 1 wherein the nonoxidizing atmosphere is nitrogen.

5. Carbonaceous grains according to claim 1 wherein the heat treatment is conducted at a temperature in the range from 420°

to 590°

C.

6. Carbonaceous grains according to claim 1 wherein the carbonaceous grains have an average size 1-200 μ

m.

7. Carbonaceous grains according to claim 6 wherein the average grain size is 1-20 μ

m.