Patent ID: 7138453

Claim:
A process for producing a polyester resin composition containing a thermoplastic polyester resin and layered phyllosilicate consisting of untreated phyllosilicate comprising: (A) a step for preparing a dispersion of layered phyllosilicate and water containing layered phyllosilicate and water; (B) a step for adding said dispersion of layered phyllosilicate, in an amount from 0.1 to 45 parts by weight of layered phyllosilicate based on 100 parts by weight of the thermoplastic resin, and water continuously or successively to a component having low polymerization degree of the thermoplastic polyester resin at a rate of 0.01 to 10.0 parts by weight per minute based on 100 parts by weight of the component having low polymerization degree of the thermoplastic polyester resin; and (C) a step for polymerizing the thermoplastic polyester resin.