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Production of hollow carbon fibers and hollow carbon particles includes baking and carbonization of polymer particles having a specified volume after deformation. A metal-deposited carbon fiber with metal deposited inside and/or outside the hollow carbon fiber is applicable to electron discharge dev

Production of hollow carbon fibers and hollow carbon particles includes baking and carbonization of polymer particles having a specified volume after deformation. A metal-deposited carbon fiber with metal deposited inside and/or outside the hollow carbon fiber is applicable to electron discharge devices. The thickness and crystallinity of the graphite layer can be freely controlled. Since almost no by-product is generated, separation and refining using a solvent is not required. A hollow carbon particle of desired shape can be produced at a high yield rate. The hollow carbon fiber represented by a carbon nano-tube can be controlled in such a way that a low resistance and uniform shape are provided so that there is an increase in the amount of electrons discharged from the hollow carbon fiber. Use of this hollow carbon fiber as an electron discharge source provides an excellent electron discharge device characterized by stable pixels.

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What is claimed is: 1. A hollow carbon fiber production method, forming carbon nano-tubes, comprising a step of forming the carbon nano-tubes by forming a shell comprising polyacrylonitrile resin on a thermally decomposable polymer which disappears by thermal decomposition reaction, and thermally d

What is claimed is: 1. A hollow carbon fiber production method, forming carbon nano-tubes, comprising a step of forming the carbon nano-tubes by forming a shell comprising polyacrylonitrile resin on a thermally decomposable polymer which disappears by thermal decomposition reaction, and thermally decomposing the thermally decomposable polymer, wherein a content of metal and metallic compound thereof does not exceed 1 percent by weight, and wherein no metal or metallic compound is used in steps of production thereof. 2. A hollow carbon fiber production method according to claim 1, wherein the step of forming the carbon nano-tubes includes a step of producing micro-capsules comprising the polymer disappearing due to thermal decomposition and the polyacrylonitrile resin, end baking said micro-capsules subsequent to melting and spinning. 3. A hollow carbon fiber production method according to claim 2, wherein a residual carbon percentage of said polymer disappearing due to thermal decomposition does not exceed 10 percent by weight and that of polyacrylonitrile resin does not exceed 15 percent by weight. 4. A hollow carbon fiber production method according to claim 2, wherein said micro-capsules are prepared by interfacial chemical technique. 5. A hollow carbon fiber production method according to claim 2, wherein said micro-capsules are prepared by seed polymerization. 6. A hollow carbon fiber production method according to claim 1, wherein said polyacrylonitrile resin is formed of monomers comprising a radically polymerizable group. 7. A hollow carbon fiber production method according to claim 6, wherein said polyacrylonitrile resin has 35 mole percent or more of units formed of polyacrylonitrile monomers contained in polymer. 8. A hollow carbon fiber production method according to claim 1, wherein said polymer disappearing due to thermal decomposition is formed of a monomer comprising a radically polymerizable group. 9. A hollow carbon fiber production method according to claim 1, wherein the polymer disappearing due to thermal decomposition and the polyacrylonitrile resin are formed of a monomer comprising a radically polymerizable group, and a compound wherein carbon remains as a major component in the process of carbonization is used as a polymerization initiator. 10. A hollow carbon fiber production method according to claim 1, wherein the polymer disappearing due to thermal decomposition and the polyacrylonitrile resin are formed of a monomer comprising a radically polymerizable group, and a compound comprising only elements selected from the group consisting of carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur, fluorine, chlorine, bromine and iodine is used as a polymerization initiator. 11. A hollow carbon fiber production method according to claim 1, wherein a difference in softening temperature between that of the thermally decomposable polymer and that of the polyacrylonitrile resin is at most 100째 C. 12. A composite comprising the hollow carbon fiber produced by the hollow carbon fiber production method according to claim 1 and a resin. 13. A hollow carbon fiber production method according to claim 1, wherein said shell consists essentially of polyacrylonitrile resin. 14. A hollow carbon fiber according to claim 1, wherein the hollow carbon fiber produced by the production method has a diameter of 3-12 nm. 15. A hollow carbon fiber production method, forming a carbon nano-tube, comprising a step of forming the carbon nano-tube by forming a shell comprising polyacrylonitrile resin on a thermally decomposable polymer which disappears by Thermal decomposition reaction, and thermally decomposing the thermally decomposable polymer, wherein a content of metal and metallic compound thereof does not exceed 1 percent by weight, and wherein no metal or metallic compound is eliminated or refined in steps of production thereof. 16. A hollow carbon fiber production method according to claim 15, wherein the step of forming the carbon nano-tube includes a step of producing micro-capsules comprising the polymer disappearing due to thermal decomposition and the polyacrylonitrile resin, and baking said micro-capsules subsequent to melting and spinning. 17. A hollow carbon fiber production method according to claim 16, wherein a residual carbon percentage of said polymer disappearing due to thermal decomposition does not exceed 10 percent by weight and that of the polyacrylonitrile resin does not exceed 15 percent by weight. 18. A hollow carbon fiber production method according to claim 16, wherein said micro-capsules are prepared by interfacial chemical technique. 19. A hollow carbon fiber production method according to claim 16, wherein said micro-capsules are prepared by seed polymerization. 20. A hollow carbon fiber production method according to claim 15, wherein said polyacrylonitrile resin is formed of monomers comprising a radically polymerizable group. 21. A hollow carbon fiber production method according to claim 20, wherein said polyacrylonitrile resin has 35 mole percent or more of units formed of acrylonitrile monomers contained in polymer. 22. A hollow carbon fiber production method according to claim 15, wherein said polymer disappearing due to thermal decomposition is formed of a monomer comprising a radically polymerizable group. 23. A hollow carbon fiber production method according to claim 15, wherein the polymer disappearing due to thermal decomposition and the polyacrylonitrile resin are formed of a monomer comprising a radically polymerizable group, and a compound wherein carbon remains as a major component in the process of carbonization is used as a polymerization initiator. 24. A hollow carbon fiber production method according to claim 15, wherein the polymer disappearing due to thermal decomposition and the polyacrylonitrile resin are formed of a monomer comprising a radically polymerizable group, and a compound comprising only elements selected from the group consisting of carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur, fluorine, chlorine, bromine and iodine is used as a polymerization initiator. 25. A composite comprising the hollow carbon fiber produced by the hollow carbon fiber production method according to claim 15 and a resin. 26. A hollow carbon fiber production method according to claim 15, wherein said shell consists essentially of polyacrylonitrile resin. 27. A hollow carbon fiber according to claim 15, wherein the hollow carbon fiber produced by the production method has a diameter of 3-12 nm. 28. A hollow carbon fiber, said hollow carbon fiber being a carbon nano-tube, wherein a content of metal and metallic compound thereof does not exceed 1 percent by weight, and being formed of polymer disappearing due to thermal decomposition and a carbon shell comprising polyacrylonitrile resin. 29. A composite comprising the hollow carbon fiber according to claim 28 and a resin. 30. A hollow carbon fiber according to claim 28, wherein said carbon shell consists essentially of polyacrylonitrile resin. 31. A hollow carbon fiber according to claim 28, wherein the hollow carbon fiber has a diameter of 3-12 nm.