Abstract: It is an object of the present invention to provide a hollow bottle made of polyester, which has excellent heat resistance and is not likely to undergo deformation or change in capacity even if a liquid of high temperature is filled therein. The present invention relates to a hollow bottle formed by blow molding polyester, which has a thickness in the range of 200 to 400 ?m, and satisfies that ?d=d1?d2 is not less than ?7 kg/m3 and more than 7 kg/m3, with d1 [kg/m3] being a density of a part ranging from an outer surface up to 50 ?m inward, and d2 [kg/m3] being a density of a part of the body portion ranging from an inner surface up to 50 ?m inward. The polyester is preferably polyethylene terephthalate, and it is preferable that d1=1370 to 1375 kg/m3, while d2=1373 to 1378 kg/m3.

Abstract: It is an object of the present invention to provide a hollow bottle made of polyester, which has excellent heat resistance and is not likely to undergo deformation or change in capacity even if a liquid of high temperature is filled therein. The present invention relates to a hollow bottle formed by blow molding polyester, which has a thickness in the range of 200 to 400 ?m, and satisfies that ?d=d1?d2 is not less than ?7 kg/m3 and not more than 7 kg/m3, with d1 [kg/m3] being a density of a part ranging from an outer surface up to 50 ?m inward, and d2 [kg/m3] being a density of a part ranging from an inner surface up to 50 ?m inward. The polyester is preferably polyethylene terephthalate, and it is preferable that d1=1370 to 1375 kg/m3, while d2=1373 to 1378 kg/m3.

Abstract: The refillable polyester bottle of the invention has a mean crystallinity of 32 to 70% at the bottle body, a methanol adsorption of 1,500 ppm or less at the same portion and a paraxylene adsorption of 300 ppm or less at the same portion. Therefore, the bottle is excellent in non-adsorptivity and heat resistance. According to the method of removing adsorbates on a polyester bottle of the invention, the adsorbates can be rapidly desorbed by holding the bottle in air of 40 to 150.degree. C. or bringing the bottle into contact with water or water vapor heated at 40 to 150.degree. C.

Abstract: The refillable polyester bottle of the invention has a mean crystallinity of 32 to 70% at the bottle body, a methanol adsorption of 1,500 ppm or less at the same portion and a paraxylene adsorption of 300 ppm or less at the same portion. Therefore, the bottle is excellent in non-adsorptivity and heat resistance. According to the method of removing adsorbates on a polyester bottle of the invention, the adsorbates can be rapidly desorbed by holding the bottle in air of 40.degree. to 150.degree. C. or bringing the bottle into contact with water or water vapor heated at 40.degree. to 150.degree. C.

Abstract: A machine for molding a starting crystalline saturated polyester resin such as polyethylene terephthalate includes a device for first drying and then preheating the starting resin to a temperature above its melting point to lower the viscosity of the resin to such an extent that the resin is not substantially degraded in the compression section of the molding machine. A feed section is provided for quantitatively feeding the molten starting resin to the main body of the molding machine. Accordingly, the starting resin is molded into a desired shape in a molding machine under conditions such that the crystallization temperature of the resulting molded article is within 20.degree. C. of the crystallization temperature of the starting saturated crystalline polyester resin.

Abstract: A crystalline saturated polyester resin such as polyethylene terephthalate, is molded into a desired shape in a molding machine under conditions such that the crystallization temperature of the resulting molded article is within 20.degree. C. of the crystallization temperature of the starting saturated crystalline polyester resin. This is accomplished by preheating the resin in the molding apparatus to a temperature above its melting point to lower the viscosity of the resin to such an extent that the resin is not substantially degraded in the compression section of the molding machine. By avoiding reductions in the crystallization temperature of the molded resin, the resin can be shaped by, for example, blow molding into a bottle or other configuration while satisfying simultaneously the requirements for transparency and dimensional stability.