To provide a composite preform that can ensure that worsening of the appearance of a surface of a plastic member caused by near-infrared heating prior to blow molding is effectively prevented and that an inner preform is efficiently heated. The composite preform of the present invention includes a preform and a heat-contractive plastic member, the preform including a mouth part; a trunk part linked to the mouth part; and a bottom part linked to the trunk part, and the heat-contractive plastic member being disposed so as to surround the outside of the preform and including at least a colored layer that contains a resin material and a colorant, wherein the heat-contractive plastic member has a near-infrared transmittance of 50% or higher.

Provided are a preform for manufacturing a synthetic resin container, in which a decorative layer (60) having three-dimensional design different from the conventional one is formed on the surface of a container main body (10a), and a synthetic resin container. In a preform (1) including a preform main body (1a) of a bottomed cylindrical shape that is opened to have a mouth portion (2) on one end side thereof, and a covering layer (6) configured to cover the preform main body (1a) except for a part thereof on a mouth portion (2) side, and a container (10) obtained by subjecting the preform to blow molding, a distal end side of the covering layer (6) (decorative layer (60)) is formed so as to reach a peripheral end edge of a neck ring (22) while covering a lower surface of the neck ring (22) that is provided on a lower end side of the mouth portion (2) and protrudes annularly along a circumferential direction.

A synthetic resin-made container has an outer layer body and an inner layer body separably laminated on an inner surface of the outer layer body and is formed by stretch blow molding, and has: a tubular mouth portion; a shoulder portion located below the mouth portion and increasing in diameter downward; a barrel portion connected to and located below the shoulder portion; and a bottom portion closing a lower end of the barrel portion, wherein the mouth portion has an outside air introduction hole for introducing outside air into a space between the outer layer body and the inner layer body, and the inner layer body is made of a crystalline resin, and has, in at least a part of the mouth portion in the inner layer body, a crystallized region having a higher degree of crystallinity than other regions.

A method for manufacturing a resin container includes: injection-molding a first layer of a bottomed cylindrical preform from a first resin material as a first injection-molding; accommodating the first layer manufactured in the first injection-molding in a temperature adjustment mold, adjusting a temperature of the first layer, and forming an opening portion in a bottom portion of the first layer; injecting a second resin material from the opening portion to an inner peripheral side of the first layer to laminate a second layer on the inner peripheral side of the first layer, as a second injection-molding; and blow-molding a multilayer preform obtained in the second injection-molding-step in a state where the multilayer preform includes residual heat from the injection molding to manufacture the resin container.

The disclosure provides a preform layered body and a layered container produced by biaxial stretch-blow forming of the layered body. In this preform layered body, an RFID tag has been inserted between an inner-layer-use mouth part and an outer-layer-use mouth part that are to remain unaltered, with no biaxial stretch-blow forming performed thereon, as a container mouth part for a layered container. Since the container mouth part does not become exposed to the high temperature and high pressure for stretch-blow forming purposes, abuses to the RFID tag, such as damage, breakage, and deformation, which arise from the heating, pressurization, and stretching during the stretch-blow forming, can be avoided reliably. In addition, labor-saving and counterfeit prevention effect can be anticipated by causing the RFID tag to hold product information.

A pre-form assembly to make a container (110) for beverages comprises an external pre-form (12) and an internal pre-form (14), each configured to form respectively an external drum (112) and an internal bag (114) of the container (110). The internal pre-form (14) is associable internally with the external pre¬form (12) so as to define with the external pre-form (12) a hollow space (13), and the internal (14) and external (12) pre-forms comprise respective coupling members (30, 34, 38) in correspondence with respective neck portions (22, 26) suitable to reciprocally position the external pre-form (12) and the internal pre-form (14) along a longitudinal axis (X).

A double container includes: an outer layer body including an outer mouth portion and a barrel portion; an inner layer body including an inner mouth portion and a containing portion; an outside air introduction port for introducing outside air; and a plurality of vertical ribs arranged with spacing in a circumferential direction on an inner surface of the outer layer body or an outer surface of the inner layer body, and each extending over the outer mouth portion to the shoulder portion or extending over the inner mouth portion to the containing portion, wherein at least one of the plurality of vertical ribs faces the outside air introduction port.

A set of preforms to make a container for beverages, comprising an external preform and an internal preform, each intended to form respectively an external keg and an internal bag of the container. The internal preform is associated internally with the external preform in order to define with the external preform a hollow space. The external preform and the internal preform have respective coupling members suitable to clamp the external preform and the internal preform with respect to each other in a desired reciprocal position.

[Problem] To provide a composite preform that can ensure that worsening of the appearance of a surface of a plastic member caused by near-infrared heating prior to blow molding is effectively prevented and that an inner preform is efficiently heated. [Solution] The composite preform of the present invention includes a preform and a heat-contractive plastic member, the preform including a mouth part; a trunk part linked to the mouth part; and a bottom part linked to the trunk part, and the heat-contractive plastic member being disposed so as to surround the outside of the preform and including at least a colored layer that contains a resin material and a colorant, wherein the heat-contractive plastic member has a near-infrared transmittance of 50% or higher.

A preform can be made from two different materials that do not bond together by a bi-injection process, using the same mold. First an outer preform can be fashioned first, then an inner preform molded through a center hole in the outer preform, and the preforms connected. Inner/outer preform materials can be different, e.g., PET/polyolefin or polyamide, or the same, e.g., PET/PET. To prevent mutual bonding during molding of the second, a non-stick coating can be sprayed on a surface portion of the first preform prior to molding, the second. Manufacturing order can be either outer/inner, or inner/outer, and the non-stick coating sprayed on the inside/outside of the perform first molded.