Catalyst for polyester production, process for producing polyester using the catalyst, polyester obtained by the process, and uses of the polyester

The present invention relates to a catalyst for polyester production, a process for producing a polyester using the catalyst, a polyester obtained by the process and uses of the polyester. The present invention provides a catalyst for polyester production capable of producing a polyester with high catalytic activity, a process for producing a polyester using the catalyst and a polyester produced thereby. The catalyst comprises a solid titanium compound obtained by dehydro-drying a hydrolyzate obtained by hydrolysis of a titanium halide and which has a molar ratio (OH/Ti) of a hydroxyl group (OH) to titanium (Ti) exceeding 0.09 and less than 4. In the process, the polyester is obtained by polycondensing an aromatic dicarboxylic acid, or an ester-forming derivative thereof, and an aliphatic diol, or ester-forming derivative thereof, in the presence of the catalyst. The resulting polyester has excellent transparency and tint, a titanium content of 1 to 100 ppm, a magnesium content of 1 to 200 ppm and a magnesium to titanium weight ratio of not less than 0.01.