Patent ID: 6426024
Filing Date: 2002-07-30
Classification: B29B,B29C,B29K,Y10T

Abstract:
A process for producing a preform by injection molding an aromatic polyester which comprises at least one aromatic dicarboxylic acid selected from the group consisting of terephthalic acid and 2,6-naphthalenedicarboxylic acid as a main dicarboxylic acid component and ethylene glycol as a main diol component,wherein injection molding is carried out by an injection molding machine, which has at least one vent at the position of a cylinder between a position where the aromatic polyester is substantially molten in the cylinder of the injection molding machine and the position of the front-end of the metering zone of a screw when the molten aromatic polyester is stored in the front-end portion of the cylinder of the injection molding machine for injection molding, while air is exhausted from the vent under reduced pressure.