WO2008025331A2

WO2008025331A2 - Method for producing tube-type bodies and corresponding tube-type body

Info

Publication number: WO2008025331A2
Application number: PCT/DE2007/001499
Authority: WO
Inventors: Anton Demarmels; Hans Kühn
Original assignee: Strecktech Ag
Priority date: 2006-09-01
Filing date: 2007-08-21
Publication date: 2008-03-06
Also published as: WO2008025331A3; DE102007037536A1

Abstract

The invention relates to a method for producing tube-type bodies. An injection-molded preform produced from a thermoplastic material is biaxial orientation-molded in a blow mold to give a container. Molding is carried out by stretching and by adding a pressurized blowing gas. The container is removed from the blow mold as an intermediate product and a bottom zone of the container is cut off. In a final step, the edges of the cut are pressed and welded together. The container as the intermediate product is molded in such a manner that its shape deviates in at least some sections of a sidewall zone between a mouth section and a bottom opposite said mouth section from a cylindrical basic contour.

Description

Process for producing tube-like bodies and a tube-like body

The invention relates to a method for producing a tube-like body.

The invention further relates to a tube-like body which is formed as a separate part of a blow-molded and biaxially oriented container made of a thermoplastic material.

Such tube-like bodies may be formed, for example, as a tube according to common usage, which has a threaded or bouncing cams or undercuts provided mouth portion on which a rotary closure is placed. Starting from the threaded mouth section, such a tube has a shoulder region which leads the mouth section over a cross-sectional enlargement into a main part of the body. In the area of the mouth section remote part of such a tube is closed.

Conventional production methods for producing such tubes are, for example, the production of tube-shaped preforms from a foil material, which is subsequently welded to an injection-molded mouth section with an integrally formed shoulder. There are also so-called deep-drawing processes in which the tube-like bodies are produced from injection-molded preforms.

In WO 97/40972 the production of a tube-like body is described in which first a container-like body is blow-molded and then a bottom portion of this container is cut open.

For blastechnischen production of containers from previously injection molded preforms different methods and devices are already known.

In this case, a preform is stretched by a stretching rod after a thermal conditioning within a blow mold and is converted into the container by blowing pressure. The stretch rods are often positioned by pneumatic cylinders or cam controls.

In the case of container molding by blowing pressure, preforms made of a thermoplastic material, for example preforms made of PET (polyethylene terephthalate), are fed to different processing stations within a blow molding machine. Typically, a der-type blowing machine has a Heating device and a blowing device, in the region of the previously tempered preform is expanded by biaxial orientation to a container. The expansion takes place by means of compressed air, which is introduced into the preform to be expanded. The procedural sequence in such an expansion of the preform is explained in DE-OS 43 40 291. The introductory mentioned introduction of the pressurized gas also includes the introduction of compressed gas into the developing container bubble and the introduction of compressed gas into the preform at the beginning of the blowing process.

The basic structure of a blowing station for container molding is described in DE-OS 42 12 583. Possibilities for temperature control of the preforms are described in DE-OS 23 52 926.

Within the blow molding apparatus, the preforms as well as the blown containers can be transported by means of different handling devices. In particular, the use of transport thorns, onto which the preforms are attached, has proven to be useful. The preforms can also be handled with other support devices. The use of grippers to manipulate preforms and the use of spreaders insertable into a muzzle area of the preform for mounting are also among the designs available.

The already described handling of the preforms takes place, on the one hand, in the so-called two-stage process, in which the preforms are first produced in an injection molding process, then interposed. stored and later conditioned in terms of their temperature and inflated to a container. On the other hand, there is an application in the so-called one-step process, in which the preforms are suitably tempered immediately after their injection-molding production and sufficient solidification and then inflated.

With regard to the blowing stations used, different embodiments are known. In blow stations, which are arranged on rotating transport wheels, a book-like Aufklappbarkeit the mold carrier is often-meet. But it is also possible to use relative to each other ver-displaceable or differently guided mold carriers. In fixed blowing stations, which are particularly suitable for receiving a plurality of cavities for container molding, typically plates arranged parallel to one another are used as mold carriers.

The hitherto known methods for producing tube-like bodies are not yet sufficiently suitable for fulfilling all requirements for an application-oriented optimal design of the tube-shaped bodies.

The object of the present invention is to improve a method of the aforementioned type such that increased design options are provided in the specification of the shape of the tube-shaped body.

This object is achieved in that the following steps are carried out sequentially: a) injection molding production of a preform made of a thermoplastic material,

b) inserting the preform into a blow mold,

c) biaxially expanding the preform to a container by stretching and supplying a pressurized blast gas,

d) shaping of the container with a design which deviates at least regionally from a cylindrical basic contour in a side wall region between a mouth section and a bottom opposite the mouth section,

e) removal of the container from the blow mold,

f) cutting off the bottom of the container along a cutting edge,

g) closing the end portion opposite the mouth portion.

In particular, blown air can be used as blowing gas.

Another object of the present invention is to form a tube-like body of the aforementioned type such that a variety of shapes are supported.

This object is achieved in that a side wall portion of the body, which is located between a mouth portion and the mouth portion - ^• D ""

has oppositely arranged closed end portion of the body, at least before closing the end portion has at least one of a cylindrical base contour deviating design.

In this case, a cylindrical basic contour is understood to mean both an exactly cylindrical shape and a shape which is created by compressing a cylindrical initial contour. In known tubes, compression and welding of the end portion opposite the mouth portion occurs, so that the actual shape of the tube becomes progressively flatter and wider at the same time as starting from a cylindrical configuration near the mouth portion toward the closed end portion. As a result, a cross-sectional area of the tube changes continuously, starting from the mouth section in the direction of the end section, from a circular shape via oval-like shapes to an end contour composed of rounded sections. However, the regions of the tubes which are compressed prior to the execution of the welding process also have an original cylindrical basic contour.

Notwithstanding the known methods, in which a cylinder-like tube blank is produced before the closing of the end region, according to the invention a tube blank is produced which has, at least in sections, a design deviating from the basic cylindrical contour. This manufacturing step and the corresponding tube design create considerable freedom in the design specification for the finished tube. An essential feature of the process is the complete separation of the bottom area of the container. In this case, the bottom region does not necessarily comprise only the actual region of the container bottom but optionally also a part of the side wall region extending between this bottom and the mouth section. The concrete localization of the cutting plane can be done depending on the application. In particular, it is not absolutely necessary that a separation is carried out perpendicular to a center line of the container, but it can be specified depending on the application obliquely to the center line dividing planes. Also, the production of a smooth cutting edge is not necessarily specified, but depending on the cutting tool used, the contour of the edge can be adapted to the respective production requirements or the respective product design optimized. For example, it is possible to make the contour wave-shaped, whereby a freshness or cold effect is suggested.

High production rates are particularly supported by the fact that the production of the container is carried out in a two-stage process.

To introduce sufficiently large stretching forces, it is proposed that the stretching operation be carried out using a stretching rod.

Low cost production is assisted by making the container from a preform having a monolayer construction. In particular, it is also possible to use a multi-layer structure. In a multilayer structure, for example, a layer may be formed as a barrier layer to to prevent and reduce the passage of gases. It is also possible in the packaging of certain products, to provide an inner layer with properties that avoids or reduces adhesion of the product.

A typical production process is carried out such that a bottle-shaped container is produced as a container.

According to a preferred application it is provided that a tube is produced as a tube-like body.

According to a production variant, it is envisaged that the welding of the cut edge is carried out before filling the tube-shaped container.

According to another production method, it is also possible that the welding of the cut edge is carried out after filling the tube-shaped container.

A favorable distribution of material can be achieved that during the blow molding of the container, a Blasgaszufuhr is performed only after completion of the stretching process.

It also contributes to an advantageous distribution of material that the blowing pressure is supplied with a slow pressure increase of at most 100 bar / second.

A sufficiently slow increase in blowing pressure can be achieved by supplying the blowing pressure with the interposition of a throttle. _ Q -

A further advantageous influencing of the material distribution takes place in that the stretching process is carried out with a stretching ratio of at most 2.0 to 2.5 relative to the length of the container relative to the preform.

When carrying out a so-called preferential heating for the production of bottles with oval-like or similar cross-sectional contour, it proves to be advantageous that when performing a non-uniform in the circumferential direction tempering of the preform, the preform is heated simultaneously by two opposing radiant heaters.

A targeted uneven distribution of material in the wall of the tube-like container can be achieved in that the preforms are heated unevenly on opposite sides.

A very accurate temperature control in the wall of the preform can be achieved by holding the preforms while carrying out their heating by a transport element which is coupled with a mechanical position control, which gradually specifies rotational movements of the preform.

To a uniform basic temperature, it helps that the preform rotates during the performance of a basic temperature at a speed of at least two revolutions per second about its longitudinal axis. In the drawings, embodiments of the invention are shown schematically. Show it:

1 is a perspective view of a blow molding station for the production of containers from preforms,

2 shows a longitudinal section through a blow mold, in which a preform is stretched and expanded,

3 shows a sketch to illustrate a basic structure of a device for blow-molding containers,

4 shows a modified heating section with increased heating capacity,

5 is a side view of a container with a separate floor area,

6 is a schematic representation of a production plant for the production and filling of tube-like bodies,

7 shows a tube with undercut in the sidewall area,

8 is an illustration for illustrating a surface structure in the region of the tube-shaped container and

Fig. 9 is a perspective view of a container with a truncated pyramid-like closure cap and relative to a longitudinal axis twisted course of the side walls. Before explaining the detailed production steps for the production of the tube-shaped body, the blow-molding process and the blow-molding device for forming injection-molded preforms (1) into the containers (2) produced as an intermediate product will be explained below.

The basic structure of a device for forming preforms (1) in container (2) is shown in FIG. 1 and in FIG. 2.

The device for forming the container (2) consists essentially of a blowing station (3) which is provided with a blow-mold (4) into which a preform (1) can be inserted. The preform (1) may be an injection-molded part of polyethylene terephthalate. It is also thought to form the preform (1) made of polypropylene. Also, the use of polyethylene or polyamide or mixtures of the above materials is possible.

In order to allow the preform (1) to be inserted into the blow mold (4) and to allow the finished container (2) to be removed, the blow mold (4) consists of mold halves (5, 6) and a bottom part (7) made of a lifting device (8) is positionable. The preform (1) can be held in the region of the blowing station (3) by a transport mandrel (9) which, together with the preform (1), passes through a plurality of treatment stations within the device. But it is also possible to use the preform (1), for example via pliers or other handling means directly into the blow mold (4). To allow a compressed air supply line below the transport mandrel (9) a connecting piston (10) is arranged, which feeds the preform (1) compressed air and at the same time makes a seal relative to the transport mandrel (9). In a modified construction, it is basically also conceivable to use solid compressed air supply lines.

A stretching of the preform (1) takes place in this embodiment by means of a stretching rod (11), which is positioned by a cylinder (12). According to another embodiment, a mechanical positioning of the stretch rod (11) is carried out over curve segments, which are acted upon by Abgriff rollers. The use of curve segments is particularly useful when a plurality of BlasStationen (3) are arranged on a rotating blowing wheel.

In the embodiment shown in Fig. 1, the stretching system is designed such that a tandem arrangement of two cylinders (12) is provided. From a primary cylinder (13), the stretch rod (11) is first moved to the area of a bottom (14) of the preform (1) before the beginning of the actual stretching operation. During the actual stretching process, the primary cylinder (13) with extended stretching rod together with a carriage (15) carrying the primary cylinder (13) is positioned by a secondary cylinder (16) or via a cam control. In particular, it is thought to use the secondary cylinder (16) such a cam-controlled that a current stretching position is specified by a guide roller (17) which slides during the execution of the stretching process along a curved path. The guide roller (17) is from the secondary cylinder (16) against the guideway pressed. The carriage (15) slides along two guide elements (18).

After closing the mold halves (5, 6) arranged in the region of carriers (19, 20), the carriers (19, 20) are locked relative to one another by means of a locking device (40).

To adapt to different shapes of a mouth portion (21) of the preform (1), the use of separate threaded inserts (22) in the region of the blow mold (4) is provided according to FIG.

Fig. 2 shows in addition to the blown container (2) and dashed lines drawn the preform (1) and schematically a developing container bladder (23).

Fig. 3 shows the basic structure of a blow molding machine, which is provided with a heating section (24) and a rotating blowing wheel (25). Starting from a preform lingseingäbe (26), the preforms (1) of transfer wheels (27, 28, 29) transported in the region of the heating section (24). Along the heating section (24) heating radiator (30) and blower (31) are arranged to temper the pre-moldings (1). After a sufficient temperature control of the preforms (1), they are transferred to the blowing wheel (25), in the region of which the blowing stations (3) are arranged. The finished blown containers (2) are fed by further transfer wheels to a delivery line (32).

In order to be able to transform a preform (1) into a container (2) in such a way that the container (2) has material properties which have a long usefulness of products filled inside the container (2), For example, to ensure food, especially drinks or cosmetic products, special process steps in the heating and orientation of the preforms (1) must be complied with. In addition, advantageous effects can be achieved by adhering to special dimensioning regulations. The use of the tubes according to the invention also makes it possible, for example, to package medical, cosmetic, pharmaceutical and chemical contents, in particular also adhesives.

As a thermoplastic material different plastics can be used. For example, PET, PEN, PA or PP can be used.

The present invention also relates in particular to the novel use of tubes for the packaging of the products mentioned above or below. The combination of the tubes and / or packages, which are produced according to the method according to the invention, with one or more of the listed products to be packaged thus represents an independent idea of the invention.

The expansion of the preform (1) during the orientation process takes place by compressed air supply. The compressed air supply is in a pre-blowing phase in which gas, for example compressed air, is supplied at a low pressure level and subdivided into a subsequent main blowing phase in which gas at a higher pressure level is supplied. During the pre-blowing phase, compressed air with a pressure in the interval of 10 bar to 25 bar is typically used and during the Main blowing phase is compressed air supplied with a pressure in the interval of 25 bar to 40 bar.

From Fig. 3 it can also be seen that in the illustrated embodiment, the Heiκstrecke (24) of a plurality of rotating transport elements (33) is formed, which are strung together like a chain and guided by Um-steering wheels (34). In particular, it is thought that the chain-like arrangement would open up a substantially rectangular basic contour. In the illustrated embodiment, in the area of the transfer wheel (29) and an input wheel (35) facing the expansion of the heating section (24) a single relatively large-sized guide wheel (34) and in the area of adjacent deflections two comparatively smaller dimensioned deflection wheels (36) used. In principle, however, any other guides are conceivable.

To enable a possible dense arrangement of the transfer wheel (29) and the input wheel (35) relative to each other, the arrangement shown to be particularly useful, since three deflection wheels (34, 36) are positioned in the region of the corresponding extent of the heating section (24) , In each case the smaller deflection wheels (36) in the region of the transition to the linear curves of the heating section (24) and the larger deflection (34) in the immediate transfer area to the transfer wheel (29) and the input wheel (35). As an alternative to the use of chain-like transport elements (33), it is also possible, for example, to use a rotating heating wheel.

After a finished blowing of the containers (2), these are removed from a removal wheel (37) from the area of the blower. Stations (3) led out and transported via the transfer wheel (28) and an output wheel (38) to the output path (32).

In the modified Heizstrek- ke (24) shown in Fig. 4 can be tempered by the larger number of radiant heaters (30) a larger amount of deformations (1) per unit time. The fans (31) introduce cooling air into the region of cooling air ducts (39), which in each case oppose the associated radiant heaters (30) and emit the cooling air via outflow openings. Due to the arrangement of the outflow directions, a flow direction for the cooling air is realized essentially transversely to a transport direction of the preforming rings (1). The cooling air ducts (39) can provide reflectors for the heating radiation in the area opposite the radiant heaters (30), and it is likewise possible to realize cooling of the radiant heaters (30) via the discharged cooling air.

Now that the production steps for producing the container used as an intermediate (2) have been explained in more detail, with reference to Fig. 5, the explanation of the production of further production steps. To produce a tube-shaped container (41), a bottom region (42) is separated from the container (2). This can be done mechanically or using other suitable separation methods. The bottom region (42) is removed from the tube-shaped container (41) and can be supplied for further use, for example material recycling.

FIG. 6 shows a production plant in which all production steps are combined locally. be carried out. Granular Ausgangsma- material (43) is fed to an injection molding device (44) and converted here to the preforms (1). The preforms (1) are fed to a blowing device (45) and formed there into the containers (2). The containers (2) are then a cutting device

(46) which separates the bottom regions (42) from the remaining region of the containers (2) and thereby provides the tumbled containers (41). The tube-shaped containers (41) are fed in a further production step to a filling device (47), which introduces a filling material into the tube-shaped container (41). In such a method, the mouth portion (21) of the tube-shaped container (41) was closed in advance. This can be done for example by screwing or bouncing a lid and / or applying a muzzle seal. The filling process is thus through the open the mouth portion (21) opposite region of the tube-shaped container

(41) previously generated by cutting off the bottom portion (42).

In a final production step, the filled tube-shaped container (41) is fed to a welding device (48) which closes the region of the tube-shaped container (41) opposite the mouth section (21) in the region of a cut edge (49).

Deviating from the production concept in FIG. 6, different variants can be realized. In particular, it is not necessary to operate all components shown at a common production station. For example, it is possible, the injection molding device (44) locally separated from the blower (45) and to temporarily store and / or transport the preforms (1). It is also possible to combine the injection molding device (44) and the blowing device (45) into a common so-called single-stage plant.

As an alternative to the illustrated sequence of filling the tube-shaped body 41 in a first step of closing the cutting region in a second production step, it is also possible first to close the cutting region and then to fill the tube-shaped container with the end region already closed by the mouth section 21 ). The concrete selected order of the single production steps takes place in dependence on the specifications of a respective user and on the characteristics of the product to be filled.

According to FIG. 6, the cutting device (46) is provided on the input side with an input device (50) and on the output side with an output device (51). Between the input device (50) and the output device (51), a separating device (52) which carries out the separating process directly is arranged.

According to a particular method step, it is also intended to rework the cutting area after the welding operation has been carried out in order to achieve an optimally designed edge contour. In particular, it is thought to perform a trimming of the edge along the weld after performing the welding process. This provides a smooth edge that avoids sharp and / or rough surface areas. The cutting process can be performed, for example, mechanically or using another of the standing explained cutting or separation process can be performed. Alternatively, it is also thought, instead of the above-described sequential implementation of the welding process as well as the trimming of the edge to perform these two operations at least partially in time parallel.

Depending on the particular application and production conditions, the cutting process in the region of the welding edge can take place both on an empty tube-like body and after a filling process has been carried out.

When blowing the container (2) with the design according to the invention is ensured by suitable process parameters that an uneven application of the container wall to the inside of the blow mold (4) and thus an uneven cooling is avoided. In particular, the corresponding blowing process is optimized in that first without supplying a blowing pressure or only with low blowing pressure support, a complete stretching of the preform (1) takes place. Only after the stretching operation, the transverse expansion of the preform (1) by the Blasdruckzufuhr. Even with a non-uniform concern of the blown container (2) on the blow mold (4) is avoided by the already completed stretching of the preform (1) the occurrence of unwanted unevenness in the material distribution.

In particular, it proves to be advantageous to supply the blowing pressure not abruptly after the implementation of the stretching, but with relatively slow pressure build-up. This can be achieved, for example, that a throttle in the supply line for the High pressure is used. With regard to the use of polypropylene as a material for the tube, a stretching factor in the range of 2 to 2.5 proves to be advantageous, the stretching factor describing the length ratio of the blown container (2) to the preform (1).

Due to the material properties of the polypropylene, it also proves to be advantageous, during the tempering of the preforms (1), to specify a comparatively high rotational speed of the preforms (1) about their preform longitudinal axes. A fast rotation is understood to mean a speed of at least one revolution per second. Particularly preferred is a speed of at least two revolutions per second.

In the production of blown tube blanks with an at least partially oval-like basic contour takes place in carrying out the heating of the preforms (1) in the circumferential direction uneven temperature. This tempering can be caused, for example, by passing the preforms (1) stepwise or at a modulated rotational speed past the radiant heaters (30). In this case, it has proved particularly useful to position the preforms (1) during heating in the region of a support element which passes through its trajectory in a curve-controlled manner. This makes it possible to support an exact and exactly reproducible temperature control.

The generation of the temperature profile in a circumferential direction of the preforms (1) takes place in particular in such a way that in those wall regions which are deformed by the blow molding in the longitudinal sides of the oval-like basic contour of the blown container, low. Riger temperatures than in those wall areas are generated, which are associated with the resulting during blow molding and shorter relative to the longitudinal sides transverse sides. As a result, a withdrawal of material from these higher tempered areas is supported.

With regard to the implementation of the heating process, it proves to be advantageous to pass the preforms (1) between two opposing radiant heaters (30). There is thus a simultaneous heating in the respective opposite areas. This contributes to an exact realization of the given temperature profile.

According to a variant of the method, it is possible to heat the opposite sides of the preform (1) unevenly intensively. As a result, in the later produced container (2), a material distribution defined in the circumferential direction is generated which is uneven. As a result, the produced tube acquires predeterminable emptying properties or assumes a predeterminable curved contour.

FIG. 7 shows a side view of a tube-shaped container (41) which is provided with a sealing seam (55) in the region of its extension opposite the mouth section (21). Along a course of the side wall of the container (41), the container

(41) has an undercut (56), in the region of which a distance of the side wall to the tube longitudinal axis

(54) decreases. The undercut (46) is formed in the illustrated embodiment as a recess. For example, this indentation can be made concave. According to a further embodiment game is the undercut (56) designed as a bulge of the side wall with increasing state to the longitudinal axis (54). In particular, a convex profile of the undercut (56) is intended.

Fig. 8 shows an embodiment with a surface structure in the region of the tube-shaped container (41). In particular, it is intended to carry out the surface structure in the form of a texturing (57). The surface structure can have both functional properties with regard to improving a slip resistance when gripping the container, as well as aesthetic properties. For example, it is possible to create the impression of condensate formation in the surface area of the container by the surface structuring and thereby convey a freshness impression.

The surface structure can be generated both by elevations and by depressions in the region of the surface of the blown container. In particular, the use of polypropylene as a material for the container increases the freedom in the specification of the surface design.

As an alternative to using abstract structures for the production of the surface design, it is also possible, for example, to perform a surface design similar to moons, crescent moon, corresponding to a starry sky, a given motif, a decor or a company logo.

Fig. 9 shows a further embodiment of the container. A corresponding container contour is essentially generated by the BlasVorgang and the container is optionally provided in a further production step as explained above with a sealed seam (55).

In principle, however, an exclusive blastechnische production is conceivable.

Fig. 9 shows an embodiment in which the container (41) is provided with a closure cap (58) which has a substantially square cross-sectional area transversely to a container longitudinal axis (59). Starting from a standing surface (60), the closure cap (58) tapers in a direction similar to a truncated pyramid in the direction of the container longitudinal axis (59).

In the region of the extension facing away from the standing surface (60), a side wall (61) of the closure cap (58) is essentially continuously transferred into a side wall (62) of the container (41). Starting from the cap (58), the side wall (62) of the container (41) extends around the container longitudinal axis (49) and rotates in a flat end piece (63). The end piece (63) can be designed as a sealed seam (55).

Fig. 9 illustrates in particular in the perspective view of the longitudinal axis (59) twisted course of the side walls (61). Starting from the closure cap (58), the side walls (61) extend in the direction of the container longitudinal axis (59) initially as a continuation of the truncated conical contour of the closure cap (58) and span a substantially square base transverse to the longitudinal axis (59). In each case two corner areas (64) adjoining side walls (62) are guided by the rotation about the container longitudinal axis (59) around such that these in the region of the end piece (63) are arranged side by side in a common plane. A course of the side walls (62), which abut one another in the opposite corner region (64), is complementary to this profile, so that a tube-like configuration is provided in the region of the end piece (63). _,

By the corresponding course of the side walls (62) bordering in the region of the end piece (63) starting from the closure cap (58) opposite side walls (61) flat against each other or are merged by a curve in one another.

Claims

Patent claims

1. A method for producing a tube-like body, characterized in that the following method steps are carried out sequentially:

a) injection molding production of a preform (1) made of a thermoplastic material,

b) inserting the preform (1) into a blow mold (4),

c) biaxially expanding the preform (1) to a container (2) by stretching and supplying a pressurized blast gas,

d) forming the container (2) with a design, which, in a side wall region between a mouth section and a bottom opposite the mouth section, deviates at least in regions from a cylindrical base contour,

e) removal of the container (2) from the blow mold (4),

f) cutting off the bottom region (42) of the container (2)

g) closing of the mouth portion (21) opposite end portion.

2. The method according to claim 1, characterized in that the preparation of the container (2) is carried out in a two-stage process.

3. The method according to claim 1, characterized in that the preparation of the container (2) is carried out in a single-stage process.

4. The method according to any one of claims 1 to 3, characterized in that the stretching operation using a stretch rod (11) is performed.

5. The method according to any one of claims 1 to 4, characterized in that the container (2) is produced from a preform (1) having a monolayer structure.

6. The method according to any one of claims 1 to 4, characterized in that the container (2) is produced from a preform (1) with a multi-layer Äufbau.

7. The method according to any one of claims 1 to 6, characterized in that a bottle-shaped container is produced as a container (2).

8. The method according to any one of claims 1 to 7, characterized in that a tube is produced as a tube-like body (41).

9. The method according to any one of claims 1 to 8, characterized in that the body (41) in the direction of a tube longitudinal axis (54) is provided with an undercut.

10. The method according to claim 9, characterized in that the undercut is formed as a bulge.

11. The method according to claim 9, characterized in that the undercut is formed as a recess.

12. The method according to any one of claims 1 to 11, characterized in that the container (41) is produced with a curved center line.

13. The method according to any one of claims 1 to 12, characterized in that the container (41) tapers in the direction of the tube longitudinal axis, starting from the Mün- dungsabschnitt (21) in the direction of the cut edge (49).

14. The method according to any one of claims 1 to 12, characterized in that extending the container (41) in the direction of the tube longitudinal axis, starting from the mouth portion (21) in the direction of the cut edge (49).

15. The method according to any one of claims 1 to 14, characterized in that the container (41) in the region of its side wall substantially parallel to the tube longitudinal axis (54) has extending edges.

16. The method according to any one of claims 1 to 15, characterized in that the container (41) is formed in a transverse to the tube longitudinal axis (54) extending cross-sectional area as a polygon.

17. The method according to any one of claims 1 to 16, characterized in that the container (41) is at least partially formed in the area of its outer surface with a texturing.

18. The method according to any one of claims 1 to 16, characterized in that the container (41) is formed in the region of its outer surface at least partially with a mirror surface. -

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19. The method according to any one of claims 1 to 15, characterized in that the container (41) is oval-shaped in a transverse to the tube longitudinal axis (54) extending cross-sectional area.

20. The method according to any one of claims 1 to 19, characterized in that the container is provided in the region of its side wall with a running in ümfangsrichtung substantially uniform material thickness.

21. The method according to any one of claims 1 to 19, characterized in that the container is provided in the region of its side wall with a running in Ümfangsrichtung substantially non-uniform material thickness.

22. The method according to any one of claims 1 to 21, characterized in that in the region of the cut edge (49) a weld is produced as a decorative element.

23. The method according to any one of claims 1 to 22, characterized in that the container (41) is produced in the region of the weld with a Halterungsausneh- tion.

24. The method according to any one of claims 1 to 23, characterized in that the container (41) is made of polypropylene.

25. The method according to any one of claims 1 to 24, characterized in that during the blow molding of the container (2) a Blasgaszufuhr is performed only after completion of the stretching process.

26. The method according to any one of claims 1 to 25, characterized in that the blowing pressure is supplied with a slow pressure increase of at most 100 bar / second.

27. The method according to any one of claims 1 to 26, characterized in that the blowing pressure is supplied with the interposition of a throttle.

28. The method according to any one of claims 1 to 27, characterized in that the stretching operation is carried out with a stretch ratio of at most 2.0 to 2.5 based on the length of the container (2) relative to the preform (1).

29. The method according to any one of claims 1 to 28, characterized in that in the implementation of a non-uniform temperature in the circumferential direction of the preform (1) of the preform (1) is heated simultaneously by two opposing radiant heaters (30).

30. The method according to claim 29, characterized in that the preforms (1) are heated unevenly on opposite sides.

31. The method according to any one of claims 1 to 30, characterized in that the preforms (1) are held during the implementation of their heating by a transport element which is coupled with a mechanical position control, which predetermines rotational movements of the preform gradually.

32. The method according to any one of claims 1 to 31, characterized in that the preform (1) rotates during the implementation of a basic temperature control at a speed of at least two revolutions per second about its longitudinal axis.

33. Tubular body formed as a separated part of a blow-molded and biaxially oriented container of a thermoplastic material, characterized in that a side wall portion of the body which extends between a mouth portion (21) and the mouth portion (21). extends opposite arranged closed end portion of the body, at least partially has a deviating from a cylindrical base contour design.

34. Body according to claim 33, characterized in that the deviating from the cylindrical base contour design as in the direction of a tube longitudinal axis (54) extending undercut is formed.

35. Body according to claim 34, characterized in that the undercut is formed as a bulge.

36. Body according to claim 34, characterized in that the undercut is formed as a recess.

37. Body according to one of claims 33 to 36, characterized in that a center line of the body extends curved.

38. Body according to one of claims 33 to 37, characterized in that the Seitenwandbe- rich starting from the mouth portion (31) in the direction of a sealing seam (55) tapers.

39. Body according to one of claims 33 to 37, characterized in that the Seitenwandbe- rich starting from the mouth portion (31) in the direction of a sealed seam (55).

40. Body according to one of claims 33 to 39, characterized in that the side wall portion of the body has substantially parallel to the tube longitudinal axis (54) arranged edges.

41. Body according to one of claims 33 to 40, characterized in that a substantially perpendicular to the tube longitudinal axis (54) arranged cross-sectional area is formed as a polygon.

42. Body according to one of claims 33 to 41, characterized in that an outer surface of the side wall region is at least partially provided with a texturing.

43. Body according to one of claims 33 to 42, characterized in that the surface structure of the sidewall region has functional properties.

44. Body according to one of claims 33 to 42, characterized in that the surface structure of the side wall region has design properties.

45. Body according to one of claims 33 to 44, characterized in that an outer surface of the side wall region is at least partially provided with a mirror surface.

46. Body according to one of claims 33 to 45, characterized in that a substantially perpendicular to the tube longitudinal axis (54) arranged cross-sectional area is oval-shaped.

47. Body according to one of claims 33 to 46, characterized in that a side wall of the body in a circumferential direction has a substantially uniform wall thickness.

48. Body according to one of claims 33 to 46, characterized in that a side wall of the body pers in a circumferential direction has a substantially non-uniform wall thickness.

49. Body according to one of claims 33 to 48, characterized in that the sealed seam (55) is designed as a decorative element.

50. Body according to one of claims 33 to 49, characterized in that in the region of the sealing seam (55) is arranged a retaining recess.

51. A body according to any one of claims 33 to 50, characterized in that the thermoplastic material is formed as polypropylene.

52. Hollow body which is at least partially formed as a blow-molded and biaxially oriented container made of a thermoplastic material and which is provided in a mouth portion with a closure cap, characterized in that a side wall (42) of the container (41) relative to a container longitudinal axis (59 ) Has at least partially a helically twisted running contour.

53. Hollow body according to claim 52, characterized in that the closure cap (58) has a substantially square base (60).

54. Hollow body according to claim 52 or 53, characterized in that the side walls (62) in one the cap (58) facing away from each other are flat in one another.

55. Hollow body according to one of claims 52 to 54, characterized in that the hollow body is formed as a tube.