PURPOSE: To manufacture solid TiCl3 for the polymn. of α-olefin with superior transparency and impact strength when purple fine-grained solid TiCl3 is deposited from a liq. material contg. TiCl3, by adding TiCl4 in a specified ratio in the deposition stage.

CONSTITUTION: TiCl4 is mixed with ether or further mixed with twice as much hydrocarbon or halogenated hydrocarbon solvent as the ether to prepare a uniform liq. material, and the TiCl4 is reduced to TiCl3 by adding an org. Al compound to the liq. material. The resulting liq. material contg. TiCl3 is treated at ≥150°C to deposit purple fine-grained solid TiCl3. Thus, solid TiCl3 for the polymn. of α-olefin is manufactured. In the deposition stage, after depositing TiCl3 by ≥80% of the amount of all of TiCl3 to be deposited, TiCl4 is added in 0.2W10molar ratio of TiCl4 to all of TiCl3, and aging is continuously carried out at 60W120°C. Purple fine-grained solid TiCl3 for the polymn. of α-olefin with superior transparency, impact strength and high commercial value can be manufactured in a high yield.