A synthetic resin delamination container formed by blow molding a preform assembly having an outer preform and an inner preform, at least either one of an inner surface of the outer preform and an outer surface of the inner preform being applied with a release agent. The delamination container has: an outer layer body including an outer mouth portion and a bottomed tubular body portion being continuous with the outer mouth portion; an inner layer body including an inner mouth portion and a volume-reducible and deformable storage portion peelably laminated on an inner surface of the body portion through a release agent layer formed by the release agent; and an outside air introduction port configured to introduce outside air between the outer layer body and the inner layer body, in which an applying amount per unit area of the release agent layer is 10 to 850 mg/m.sup.2.

A method for manufacturing a container (100) having a covering layer includes: acquiring a preform (200) having a preform covering layer (204) formed by using a synthetic resin having thermoplasticity, the preform being a material for forming a container (100) having a covering layer (104) manufactured by blow molding; setting the preform (200) in a blow mold (310) wherein a blade (440) is provided to a portion of a surface of the blow mold (310) with where the container is brought into contact, the blade having a height that corresponds to a thickness of the covering layer (104); and forming the container (100) having the covering layer (104) by performing blow molding on the preform (200), the covering layer having a slit (190) formed by the blade (440).

A preform assembly includes: an outer preform that includes an outer mouth portion and a stretch portion connected to the outer mouth portion and in which a recess extending in a vertical direction is provided on an inner surface of the stretch portion; and an inner preform that includes an inner mouth portion and a stretch portion connected to the inner mouth portion, wherein an outside air introduction port communicating with a part between the outer preform and the inner preform is provided in a mouth portion composed of the outer mouth portion and the inner mouth portion located on an inner side of the outer mouth portion.

Method for making blow molded articles having a predetermined feature incorporated into the wall provided by variations in the thickness of the wall of the article corresponding to a predetermined pattern etched into the preform from which the article was formed.

A preform for molding a dual container, in which an inner preform is inserted into an outer preform in a state in which a mouth portion of the inner preform is fitted into a mouth portion of an outer preform, the inner preform is formed of a crystalline resin, a crystallized region is provided in at least a portion of the inner preform, the crystallized region having a degree of crystallization greater than that of the other portion, the portion of the inner preform adjacent to the mouth portion from below the mouth portion and located below the outside air introduction hole, a step portion facing upward and a rib extending upward from the step portion are formed on an inner circumferential surface of the inner preform, and at least a part of the rib is adjacent to the crystallized region from above the crystallized region.

Method of making a blow molded article from a preform including: a) providing a preform of a thermoplastic material having a plurality of effect structures each having an effect surface having a normal with an orientation, the preform having a body with one or more walls and an opening, wherein at least a portion of the one or more walls of the preform has a three-dimensional pattern of cavities and/or protrusions thereon; and b) blow molding the preform to form a blow molded article, wherein the step of blow molding the preform changes the orientation of the normal of at least some of the effect surfaces of the effect structures to create a visual effect in at least one wall of the blow molded article.

A plural preform assembly having nested preforms with an inner preform and an outer preform. The preforms are sealably joined together, defining a volume between the preforms. Propellant is disposed in the volume between the preforms. The preforms are later blow molded to provide a bag in bottle, bottle in bottle or similar container. The propellant charge is already present when blow molded, preventing the need for a later propellant filling step.

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.

The invention provides a mould core and injection moulding apparatus for the production of a preform using a mould core which in the zone for defining the neck part of the preform comprises a combination of a raised portion and a shallow groove with a depth of 0.01 to 1 mm provided in the raised portion, for defining an internal attachment means in the neck of the preform. The invention also provides a preform and a container made from the preform, with internal attachment means in the neck. The internal attachment means is carried out rotation symmetrically with respect to the longitudinal axis of the preform. The combinations with an insert piece, preferably a pouring spout, flexible hose or dosing cap, have also been described. Furthermore, the invention provides an injection moulding method for the preform production and a stretch blow moulding method for the container production.

A preform (3) of a plastic container, comprising an outer preform (1) and an inner preform (2) inserted into the outer preform (1); wherein the outer preform (1) and the inner preform (2) are made of a mutually different material, in particular of a mutually different polymer; wherein the outer preform (1) is provided with at least one vertical protrusion (14) in contact with the inner preform (2); and wherein the outer preform (1) is made of a polar polymer and the inner preform (2) is made of an apolar polymer.