To provide a polyester chip which hardly causes the problem of adhesion to an apparatus or mutual adhesion like a millet-and-rice cake in the surface roughening treating and surface crystallization processes and not causes an adhesion to a wall surface even at the time of performing high temperature drying.

The polyester chip comprises a polyester A having 0-5 mJ/mg of crystal melting heat amount at 5°C/min of the rate of temperature increase and a polyester B having 10-100 mJ/mg of crystal melting heat amount in the differential scanning calorimetry (DSC), in which the weigh ratio of the polyester B relative to the total of the polyester A and polyester B is ≥5% by weight and ≤50% by weight, and the crystal melting heat amount at 5°C/min of the rate of temperature increase in the temperature range of 210-270°C is 5.1-40 mJ/mg in the DSC.

COPYRIGHT: (C)2008,JPO&INPIT