Oblon, Spivak, McClelland, Maier & Neustadt
Method of producing polyolefin
 A method of producing a polyolefin, which comprises polymerizing at least one olefin in the presence of a catalyst system comprising PA1 (A) a catalyst component prepared by bringing ethylene and/or an .alpha.-olefin in contact with a solid composite obtained by reacting a reaction product, which has been produced by reacting a uniform solution containing PA2 (i) at least one member selected from the group consisting of metal magnesium and hydroxylated organic compound, and oxygen-containing organic compounds of magnesium and PA2 (ii) at least one oxygen-containing organic compound of titanium with PA2 (iii) at least one organoaluminum compound and/or PA2 (iv) at least one silicon compound, with PA2 (v) at least one aluminum halide compound, thereby allowing the ethylene and/or the .alpha.-olefin to be absorbed into the solid composite, and PA1 (B) at least one catalyst component selected from the group consisting of organometallic compounds of metals of Groups Ia, IIa, IIb, IIIb and IVb of the Periodic Table. 
Tosoh Corporation
C Y Y
C08F Y10S Y10S
inventional additional additional
Hitoshi Mitsuhiro Morihiko Yozo
Ito Mori Sato Kondo