A method of injection molding a test tube-shaped preform for biaxial stretch blow molding includes supplying a major material resin from outer and inner flow paths to a combined flow path for a predetermined time and rate. For a period of time within a range of the predetermined time period during which the major material resin is supplied, the intermediate layer resin is simultaneously supplied from the middle flow path to the combined flow path at a second predetermined supplying rate. A columnar laminated molten resin is injected into a cavity of a metal mold connected to a tip of the nozzle through a gate to fill the cavity, the columnar laminated molten resin being composed of the major material resin and the intermediate layer resin formed in the major material resin in a laminated manner that are combined into a columnar shape at the combined flow path.

To solve a problem associated with formation of a transparent window portion in a biaxially stretch blow molded container by a nozzle structure of an injection molding apparatus, provided is a biaxially stretch blow molded container formed with a clearly transparent window portion in longitudinal strip shape by effectively preventing mixture of colored resin to window portion. Injection molding apparatus includes in nozzle portion a longitudinal groove flow path, wherein a transparent B resin flows. By, for example, reducing and increasing, respectively, the width and depth of the longitudinal groove flow path on the downstream side, and engraving slits in an inner mandrel and even in a front end portion of a stopper pin, flowability of the B resin in a horizontal direction is enhanced.

A method for manufacturing a container includes injecting a first material into a first mold to form a top portion of a preform. The first material and a second material are injected into the first mold to form a bottom portion of the preform. The preform is disposed in a second mold. The preform is blow molded into a finished container.

A blow mold system including a mold body and a base portion. The mold body includes a central bore extending from a first end of the mold body to a second end of the mold body along a longitudinal axis. The first end is configured to receive a mold preform. The base portion includes a recess, and the base portion is arranged at the second end of the mold body such that the central bore and recess define a blow mold cavity in which a container may be formed from the mold preform. In embodiments, the blow mold system has at least two interchangeable base portions that allow for containers with differently-sized or differently-shaped necks to be formed.

A method of injection molding a test tube-shaped preform for biaxial stretch blow molding includes supplying a major material resin from outer and inner flow paths to a combined flow path for a predetermined time and rate. For a period of time within a range of the predetermined time period during which the major material resin is supplied, the intermediate layer resin is simultaneously supplied from the middle flow path to the combined flow path at a second predetermined supplying rate. A columnar laminated molten resin is injected into a cavity of a metal mold connected to a tip of the nozzle through a gate to fill the cavity, the columnar laminated molten resin being composed of the major material resin and the intermediate layer resin formed in the major material resin in a laminated manner that are combined into a columnar shape at the combined flow path.

A method for manufacturing a resin container includes: a first injection-molding step of injection-molding a bottomed cylindrical resin intermediate molded body; a second injection-molding step of injection-molding a resin material on an outer side of the intermediate molded body to manufacture a multilayered preform having a resin layer laminated on an outer peripheral side of the intermediate molded body; and a blow-molding step of blow-molding the preform to manufacture a resin container having a thick portion.

A manufacturing method of a resin container includes: a first injection molding process for injection-molding a first layer of a preform having a bottomed cylindrical shape by using a first resin material; a second injection molding process for injecting a second resin material having a color that is different from a color of the first resin material, and laminating a second layer on an outer peripheral side or an inner peripheral side of the first layer; and a blow-molding process for blow-molding a preform that includes multiple layers and has been obtained in the second injection molding process in a state where residual heat at a time of injection molding is contained, and manufacturing the resin container having a color pattern that corresponds to a thickness distribution of the first layer and the second layer.

A production apparatus of a two-layer preform including an inner layer preform and an outer layer preform includes: an outer layer cavity mold for injection-molding the outer layer preform. A bottom surface of the outer layer cavity mold is provided with a protrusion for separating the inner layer preform disposed in the outer layer cavity mold from the bottom surface.

Preform assembly for blow moulding a container, comprising at least a first and a second perform, wherein the first perform is positioned inside the second perform before blow moulding the performs into the container, wherein each perform has a body forming portion having a wall thickness of less than about 8 millimetres, preferably less than about 6 mm.

A manufacturing method includes an injection molding process of injection-molding a preform having a two-layer structure including an outer layer preform and an inner layer preform, and a blow molding process of blow molding the preform to mold a delamination container made of resin. The injection molding process includes an outer layer molding process of filling an outer layer injection mold with PET (outer layer resin material) to mold the outer layer preform and molding a thin film portion in a part of the outer layer preform, and an inner layer molding process of injecting PP (inner layer resin material) toward the thin film portion to break the thin film portion and filling an inner layer injection mold with PP having a temperature lower than a melting point of PET via the broken thin film portion to mold the inner layer preform.