Abstract: A hollow, blow-molded, bottle-shaped container of a biaxially oriented polyethylene terephthalate which has a stepped portion formed on the inner peripheral surface of a boundary between a neck portion and a shoulder portion with a body portion, and crystallized by a heat treatment before being biaxially oriented blow-molded from an injection-molded primary piece or parison, thereby abruptly reducing the thickness of the wall at the boundary from the neck portion to the shoulder portion to substantially equal the thickness of the body portion. This bottle-shaped container is manufactured from an injection-molded preformed piece or parison in which a recess groove is formed on the peripheral surface of the shoulder forming portion. Thus, any deterioration in the physical properties of the neck and shoulder portions of the bottle-shaped container can be eliminated.

Abstract: A hollow blow-molded bottle-shaped container of a biaxially oriented polyethylene terephthalate which advantageously has a crystallized outer peripheral portion at the neck portion except the boundary between the neck portion and the body portion and non-crystallized inner peripheral portion thereat. This bottle-shaped container is molded by a method of molding the same, which method advantageously has the steps of injection-molding a piece or parison formed at the outer peripheral surface of a neck root part forming portion in a downwardly flared tapered shape, and crystallizing by a heat treatment the outer peripheral surface portion of the neck root part forming portion. Thus, the deterioration in the physical properties of the neck and shoulder portions of the bottle-shaped container thus finally blow-molded can be reduced.

Abstract: An apparatus for biaxial-blow-molding a hollow bottle-shaped container of a synthetic resin which has a bottom mold having an upper surface becoming the bottom mold surface of the bottle-shaped container and a cylinder chamber formed therein, a bottom protruding pin having an upper end face forming part of the bottom mold surface of the bottom mold and a piston portion formed at the bottom end thereof and telescopically moved back and forth in the cylinder chamber of the bottom mold, and an elastic member disposed in the cylinder chamber of the bottom mold for urging the bottom protruding pin forwardly when the member is contacted with the piston portion of the bottom protruding pin in such a manner that the tension of the member is weaker than the pressure of compressed air to be blown into the molds. This apparatus is operated by a method of biaxial-blow-molding the hollow bottle-shaped container of a synthetic resin of the invention.

Abstract: This invention relates to process for preparing saturated polyester resin bottles, that the residual strain of the bottles is reduced and the deforming temperature is elevated. The process is that a heated intermediate material (1) made of a saturated polyester resin is set in a mold (5), then compressed air is blown in the intermediate material (1) to orient the same biaxially, temperature in thus shaped bottle is elevated to a temperature higher than the heating temperature of the intermediate material (1) under the elevated pressure to effect thermal fixing and thereafter the saturated polyester resin bottle (19) is taken out.

Abstract: A method of strengthening the neck portion of a hollow blow-molded bottle-shaped container of a biaxially oriented polyethylene terephthalate resin, which has the steps of heating the neck portion from 140.degree. to 170.degree. C., inserting a die pin of a predetermined shape into the opening of the neck portion, blowing cooling air to the neck portion, thereby shrinking and whitening the neck portion. Thus, the method prevents improper shrinkage deformation of the neck portion due to the thermal influence of the bottle-shaped container.

Abstract: A biaxially stretched molded bottle is forcibly cooled by having its outer surface contacted with a cooling fluid such as cold water or gas to avoid its deformation by the heat of a liquid poured into the bottole and elution by such heat of any constituent of the material from which it is molded, when the bottle is a molded product of a saturated polyester resin, particularly polyethylene terephthalate, which has poor heat resistance like bottles of other synthetic resins, and is filled with the liquid which is heated to a high temperature for sterilization purpose only when it is filled into such a bottle and which is allowed to return to room temperature or cooled. When the liquid is poured into the bottle through its open neck, the cooling fluid supplied for cooling the bottle is prevented from flowing into the bottle through its open neck and mixing impurities into the liquid in the bottle.

Abstract: A method of orienting the neck of a bottle of a saturated polyester resin so as to enhance the physical properties and durability of the neck. The neck orienting method includes the step of inserting an orienting rod having a taper head into the neck which is being heated. The neck orienting method may include the step of orienting only the mouth edge of the neck.

Abstract: Apparatus for drawing a mouth-neck portion of a synthetic resin bottle in the radial direction, by inserting an expanding operation zone of the apparatus into the mouth-neck portion in the heated state and expanding respective drawing pieces of the expanding operation zone in the radial direction. The apparatus includes a cylindrical wall constructed by a great number of drawing pieces, a pressing rod inserted into this cylindrical wall to expand the drawing pieces in the radial direction and an elastic tubular member to be inflated in the radial direction by high pressure compressed air.

Abstract: Herein disclosed is a method of orienting the neck of a bottle of a saturated polyester resin so as to enhance the physical properties and durability of the neck. The neck orienting method includes the step of inserting an orienting rod having a taper head into the neck which is being heated. The neck orienting method may include the step of orienting only the mouth edge of the neck.

Abstract: A biaxially oriented bottle of saturated polyester resin has a disadvantage that the mouth or the part extending from the neck to the shoulder, which is not oriented or is oriented only a little, is much poorer in durability and resistance to the content liquid than the body which is molded under sufficient orientation. Such a disadvantage has been surmounted in this invention by covering the inside of the mouth or the part extending from the neck to the shoulder, which is in direct contact with the content liquid, with a layer which is durable and resistant to the content liquid.

Abstract: Herein disclosed is a method of orienting the neck of a bottle of a saturated polyester resin so as to enhance the physical properties and durability of the neck. The neck orienting method includes the step of inserting an orienting rod having a taper head into the neck which is being heated. The neck orienting method may include the step of orienting only the mouth edge of the neck.