| 摘要 |
There is described a process for producing meso-carbon microbeads having a diameter in the range of 0.5 SIMILAR 20 mu m which comprises heat treating a pitch to produce optically anisotropic spheres and separating the said spheres from an optically isotropic matrix, which is characterized in that the said pitch is a reformed pitch produced by a process which comprises mixing a pitch having an aromatic carbon ratio fa of more than 0.6 with a Lewis acid selected from BF3, HF.BF3, anhydrous AlCl3, anhydrous CuCl2, anhydrous ZnCl2 or anhydrous SnCl2 and a co-solvent selected from the group consisting of dichlorobenzene, nitrobenzene and trichlorobenzene so as to give a mol ratio of the said Lewis acid to the said pitch in the range of 0.3 SIMILAR 5.0 and a mole ratio of the said co-solvent to the said pitch in the range of 2.5 SIMILAR 50 and reacting at a temperature of 100 SIMILAR 300 DEG C and that the heat treating temperature of the said reformed pitch to produce optically anisotropic spheres is 200 SIMILAR 380 DEG C.
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