A dual-structure container including an inner bag container (31) and an outer container (41) obtained by simultaneous stretch-blow molding according to a stack preform method using an inner bag container preform (1) and an outer container preform (3). On a body (33) of the inner bag container (31), contraction-control thin portions (50) are formal at a plurality of sites at intervals in the circumferential direction such that the thin portions (50) extend like strips in the axial direction.

The present invention relates to a method for producing a bag in the interior space of a container and for testing said bag, and to a system for this purpose, to a computer program product for execution, and to the use of the system for the methods.

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.

The invention is an integrally blow-moulded bag-in-container and preform and a method for making it. The bag-in-container has an inner layer forming the bag and an outer layer forming the container, and a mouth fluidly connecting the volume defined by the bag to the atmosphere. The container further has at least one interface vent fluidly connecting the interface between inner and outer layers to the atmosphere, wherein the at least one vent runs parallel to the interface between inner and outer layers and opens to the atmosphere at a location adjacent to, and oriented coaxially with the bag-in-container's mouth. Processes for manufacturing a preform and a bag-in-container as defined above are defined too.

In an example, a composite structure having a variable gage is described. The composite structure includes a first end having a first gage, a second end having a second gage, which is less than the first gage, a plurality of continuous plies, and a plurality of drop-off plies. Each continuous ply extends from the first end to the second end. Each drop-off ply includes a tip having a tapered shape. Each drop-off ply extends from the first end to a respective position of the tip of the drop-off ply between the first end and the second end. The tips of the plurality of drop-off plies are arranged in a monotonically-inward pattern.

In an example, a composite structure having a variable gage is described. The composite structure includes a first end having a first gage, a second end having a second gage, which is less than the first gage, a plurality of continuous plies, and a plurality of drop-off plies. Each continuous ply extends from the first end to the second end. Each drop-off ply includes a tip having a tapered shape. Each drop-off ply extends from the first end to a respective position of the tip of the drop-off ply between the first end and the second end. The plurality of drop-off plies are separated from each other by at least one of the plurality of continuous plies.

In an example, a composite structure having a variable gage is described. The composite structure includes a first end having a first gage, a second end having a second gage, which is less than the first gage, a plurality of continuous plies, and a plurality of drop-off plies. Each continuous ply extends from the first end to the second end. Each drop-off ply includes a tip having a blunt-end shape. Each drop-off ply extends from the first end to a respective position of the tip of the drop-off ply between the first end and the second end. The plurality of drop-off plies are separated from each other by at least one of the plurality of continuous plies.

A delamination container includes an engaging protrusion that is provided in an area extending over at least a ground contact portion and a recess and protrudes from either one of an outer layer body and an inner layer body and engages with the other in an undercutting manner. Further, a preform includes an engaging protrusion that is provided in an area extending from at least a boundary between a bottom and a trunk to just before an axial center of the bottom and protrudes from either one of an outer body and an inner body and engages with the other in an undercutting manner.

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 heating mat for a motor vehicle. The method includes the following steps: providing a heating ply having a deformable structure and two heating elements inserted into the structure, said two heating elements being separated by a deformation area of the structure; stacking the heating ply between an upper layer and a lower layer, wherein at least one of the heating ply and the upper and lower layers includes a thermoformable material; assembling the stack by at least one fastening rod; and thermoforming the stack thus assembled, so as to secure the heating ply and the upper and lower layers into a single piece; and stretching the deformation area in the stacking direction.