A preform for biaxial stretching blow molding. The preform being formed into a closed-end cylinder by direct blow molding and which is to be shaped into a container using a pressurizing liquid medium. The preform has either a single-layer or a multilayer structure constituted of one of a polyethylene resin having an MFR of 1.0-1.5 g/10 min. or a polypropylene resin having an MFR of 0.8 to 2.3 g/10 min.

Provided is a manufacturing method for a double container that allows easy manufacturing with a molding device not significantly different from conventional devices and that can, at a lower cost than the processing cost of conventional technology, very easily and reliably form, in a comparatively rigid outer container and in a double container that allows, inside the outer container, capacity to be varied with respect to the amount of content, an opening for allowing external air to enter. When a pair of partial molds are brought near each other in order to form a split mold, at least part of the mating faces of the pair of partial molds forms a projection by sandwiching a small outer diameter portion of a parison, a gap that passes between the double container is created by cutting off the projection, and the gap is opened and expanded by screwing on a cap.

A vessel is configured to hold a product in an interior region formed in the vessel. The vessel is formed using a blow-molding process in which a multiple layer parison is blow molded to form the vessel. The multiple layer parison is formed in an extrusion process in which a number of extruders are arranged to co-extrude associated inner and outer parisons to establish the multiple layer parison.

A preform is biaxially stretch blow molded into a container by using a liquid as a pressurizing medium. The preform is formed in a bottomed tubular shape including a mouth, a trunk, and a bottom by extrusion blow molding. The preform includes bottom parting lines, which are formed in the bottom due to the extrusion blow molding, and the bottom parting lines are configured to extend to the outer side from the axis of the bottom to divide the bottom into at least three parts in the circumferential direction. Further, a container is formed by biaxially stretch blow molding the preform by using the liquid as the pressurizing medium.

A method for producing a delamination container, wherein the delamination container includes an outer layer body constituting an outer shell of the container and an inner layer body that is laminated on an inner side of the outer layer body in a manner such that the inner layer body is peelable from the outer layer body. The inner layer body comprises an ethylene-vinyl alcohol copolymer resin, and is deformable to undergo volume reduction and the outer layer body includes an outer layer body's inside sub-layer that is located adjacent to the inner layer body and that is made of a polypropylene resin and an outer layer body's outside sub-layer that is located on an outer side of the container relative to the outer layer body's inside sub-layer and that is made of a polyethylene resin. The method comprises a process to form the delamination container by co-extruding resins in a molted state to prepare a cylindrical laminated parison and blow molding the prepared laminated parison.

A preform for biaxial stretching blow molding. The preform being formed into a closed-end cylinder by direct blow molding and which is to be shaped into a container using a pressurizing liquid medium. The preform has either a single-layer or a multilayer structure constituted of one of a polyethylene resin having an MFR of 1.0-1.5 g/10 min. or a polypropylene resin having an MFR of 0.8 to 2.3 g/10 min.

A method for producing a delamination container, wherein the delamination container includes an outer layer body constituting an outer shell of the container and an inner layer body that is laminated on an inner side of the outer layer body in a manner such that the inner layer body is peelable from the outer layer body. The inner layer body comprises an ethylene-vinyl alcohol copolymer resin, and is deformable to undergo volume reduction and the outer layer body includes an outer layer body's inside sub-layer that is located adjacent to the inner layer body and that is made of a polypropylene resin and an outer layer body's outside sub-layer that is located on an outer side of the container relative to the outer layer body's inside sub-layer and that is made of a polyethylene resin. The method comprises a process to form the delamination container by co-extruding resins in a molted state to prepare a cylindrical laminated parison and blow molding the prepared laminated parison.

Provided is a manufacturing method for a double container that allows easy manufacturing with a molding device not significantly different from conventional devices and that can, at a lower cost than the processing cost of conventional technology, very easily and reliably form, in a comparatively rigid outer container and in a double container that allows, inside the outer container, capacity to be varied with respect to the amount of content, an opening for allowing external air to enter. When a pair of partial molds are brought near each other in order to form a split mold, at least part of the mating faces of the pair of partial molds forms a projection by sandwiching a small outer diameter portion of a parison, a gap that passes between the double container is created by cutting off the projection, and the gap is opened and expanded by screwing on a cap.

Blow molded components and systems and methods for forming the same are disclosed. The blow molded component may be an air duct, for example, a structural air duct. The structural air duct may include a hollow main body including a first layer of a first material and a second layer of a second material surrounding the first layer. At least one hollow protrusion may extend from the hollow main body and may include proximal and distal portions. The proximal portion may include the first layer surrounded by the second layer and the distal portion may include only one of the first and second layers. The duct may be formed by blow molding a multi-material parison. The first and second materials may have different tensile moduli, and during the molding process the material with the higher modulus may tear and allow the lower modulus material to fill the protrusion.

A vessel is configured to hold a product in an interior region formed in the vessel. The vessel includes an inner layer arranged to define the interior region and an outer layer. The vessel is formed using a blow-molding process in which a multiple layer parison is blow molded to form the vessel. The multiple layer parison is formed in an extrusion process in which a number of extruders are arranged to co-extrude associated.