EP2925615A1

EP2925615A1 - Plastic container

Info

Publication number: EP2925615A1
Application number: EP13779141.4A
Authority: EP
Inventors: Christian Dornbach
Original assignee: Alpla Werke Alwin Lehner GmbH and Co KG
Current assignee: Alpla Werke Alwin Lehner GmbH and Co KG
Priority date: 2012-11-30
Filing date: 2013-10-17
Publication date: 2015-10-07
Anticipated expiration: 2033-10-17
Also published as: RU2015125694A; CN104853991B; IN2015DN04024A; MX2015006564A; WO2014082696A1; US9957077B2; US20150259090A1; RU2611294C2; BR112015011908A2; CH707262A2; CN104853991A; MX360392B; BR112015011908B1; EP2925615B1

Abstract

The invention relates to a plastic container, in particular for storing liquid products under slight positive pressure, which container has a container body (2) which extends along a longitudinal axis. The one longitudinal end of the container body (2) is adjoined by a container neck (3), which is equipped with at least one pouring opening (4). The other longitudinal end of the container body (2) is adjoined by a bottom section (5) which has a container bottom (6) and an edge region (8) which is drawn up laterally and which merges into the container body (2). The container bottom (6) has a concave section (9) which is curved in the direction of a container interior bounded by the container body, and the circumference of which section is connected via an axially protruding stepped transition region (10) to a standing surface (7), which opens into the edge region (8) that is drawn up laterally. The standing surface (7) and at least one sub region of the stepped transition region (10) are interrupted by a first number of grooves (11). Formed in the concave section (9) is a second number of panel-like projections (12), which extend substantially between the stepped transition region (10) and the longitudinal axis and end in front of the stepped transition region (10).

Description

Plastic containers

The invention relates to a plastic container, in particular a plastic bottle, for the storage of liquid products under a slight overpressure according to the preamble of patent claim 1.

The usual in the past containers made of white or stained, glass or ceramic are increasingly being replaced by plastic containers. In particular, for the packaging of fluid substances, such as drinks, oil, cleaning utensils, cosmetics, etc., mainly plastic containers, in particular plastic bottles are used. The low weight and the lower costs play a significant role in this substitution. The use of recyclable plastic materials and the overall more favorable overall energy balance during their production also contribute to promoting consumer acceptance of plastic containers, in particular plastic bottles.

Plastic containers, in particular plastic bottles, have a container body, to whose one longitudinal end a container neck usually adjoins, which is equipped with at least one pouring opening. The container body often has a regular, for example, circular or substantially square cross-sectional area. He can also have an oval cross-section. At the other end of the container body includes a bottom section. The bottom section comprises a container bottom and a laterally raised edge region, which merges into the container body.

The plastic container may be produced in an extrusion blow molding process from a continuous or discontinuously extruded single- or multi-layer plastic hose. In this case, a section of the extruded plastic tube is introduced into the mold cavity of a blow molding tool and inflated by a gas introduced with excess pressure, usually air, according to the mold cavity. The blown air is supplied by means of a Kalibrierblasdorns, which is retracted into the located in the mold cavity plastic tube section. The molded and cooled plastic container is removed from the mold. The plastic container may also be made in a single or multi-stage stretch blow molding process. Initially, an elongated preform (preform) is produced in an injection molding or flow molding process. The preform is inserted in a further step in the mold cavity of a blow mold and inflated by a gas introduced with excess pressure, usually air, according to the mold cavity. During the inflation process, the preform is additionally axially stretched by means of a retracted stretching mandrel. The finished stretch-blown and cooled plastic container according to the mold cavity is finally removed from the mold. A one-stage stretch blow molding process is used if the further processing of the still hot preform takes place immediately after the production of the preform. In the two-stage stretch blow molding process, the preform produced is further processed temporally and / or spatially separately, wherein it must be reheated for the actual stretch blow molding process.

In many cases, liquid products are stored in plastic containers under a slight overpressure. This slight overpressure is produced, for example, by filling the plastic container with nitrogen gas after filling. The nitrogen displaces the oxygen, which otherwise could lead to oxidation of the contents and thus reduce the shelf life of the product being filled. But even during their storage outgassing products can lead to a slight overpressure within the plastic container. This overpressure is for example 0.3 to 0.5 bar and can reach up to 1.5 bar. As a result of the overpressure, there is a certain risk that the container body deforms uncontrollably, for example bulges outwards, and thereby impairs the stability of the container. From the prior art, therefore, plastic containers are known which are equipped in the container body with weakened areas where the container body can deform to a limited extent. The remaining container body is formed with a relatively large wall thickness. Such plastic containers equipped with deformable sections in the container body are relatively complex to manufacture. In addition, the deformable sections often severely limit the space available for labeling the plastic container. Therefore, alternative approaches try to counteract a deformation of the container body in that the container bottom with more or less controlled deformable areas is trained. For example, this membrane-like container bottoms are known, which have a plurality of concentrically arranged, hingedly interconnected areas which are curved inwards and can evert outwards due to an increased internal pressure. After this deformation process of the container bottom could affect the stability of the container, the hinged interconnected areas of the container bottom are arranged between feet, which are formed in the edge region of the bottom portion. For example, plastic containers with five or more feet are known. Apart from the relatively complex design of its bottom portion, the container has a greater height due to the feet, without thereby gaining much in internal volume. The feet must be formed with a relatively large wall thickness, since the weight of the filled container is now distributed over a significantly reduced area. On the other hand, however, there is a desire, from ecological and economic considerations, to further reduce the material requirements for the plastic containers.

Object of the present invention is therefore to remedy the disadvantages of the known from the prior art plastic containers, especially plastic bottles. It is intended to provide a plastic container for the storage of liquid products under a slight overpressure, the container body is largely fully available for labeling. The plastic container should have a bottom portion which has the largest possible footprint. On feet in the edge region of the bottom section should be able to do without. In addition, the conditions for further material savings in the production of the plastic container to be created.

The solution to these partly contradictory tasks consists in a plastic container for the storage of liquid products under a slight overpressure, which has the features listed in claim 1. Further developments and / or advantageous embodiments of the invention are the subject of the dependent claims.

The invention provides a plastic container, in particular for the storage of liquid products under a slight overpressure, which creates a container body having a longitudinal axis, at one longitudinal end of which a container neck adjoins, which is equipped with at least one pouring opening. At the other longitudinal end of the container body includes a bottom portion having a container bottom and a side raised edge portion which merges into the container body. The container bottom has a concave portion curved in the direction of a container interior delimited by the container body, the circumference of which is connected via an axially projecting stepped transition region to a base which opens into the laterally raised edge region. The base and at least a portion of the stepped transition region are interrupted by a first number of grooves. In the concave portion, a second number of panel-like protrusions is formed, which extend substantially between the stepped transition region and the longitudinal axis and terminate before the stepped transition region.

The plastic container according to the invention has a bottom section whose combination of features makes it possible to fulfill the sometimes contradictory tasks. The concave portion, which may be formed dome-shaped, is connected via the stepped transition region with the base. In this case, the base surface may be formed substantially annular, when the Runststoffbehälter has a substantially circular cross-section. As a rule, the base surfaces have the geometric shape, which also has the cross section in the region of the laterally raised edge region in the container body. The stepped transition region has a hinge-like function, which allows for a small deformation of the concave portion at elevated pressure. On the other hand, the panel-like projections again give the concave portion increased rigidity. The at least one subregion of the stepped transition region and the surface-intersecting grooves impart a greater rigidity to the bottom section as a whole. The stepped transition region may consist, for example, of two stages, in which a first step adjoining the base surface is interrupted by the groove, and the second step adjacent to the concave section is not interrupted. The grooves can also interrupt the entire stepped transition region, so reach into the concave section. As a result, the grooves provide for a limitation of the hinge-like function, since the graded transition region is not continuous or circumferential, but is divided by the grooves into individual segments. By the size and the number of grooves the stiffness of the floor section can be influenced. Here, the grooves may be distributed uniformly or non-uniformly along the circumference. The combination of stiffness enhancing and in turn promoting features imparts to the bottom section just the required stability to withstand low overpressures without deformation and, on the other hand, to allow limited deformation of the container bottom at elevated internal pressures. This ensures that the container body itself remains free of deformation. As low pressures are considered for the present invention internal pressures of up to 1.5 bar, preferably from 0.3 to 0.5 bar, above ambient pressure.

The base of the plastic container is interrupted only by the grooves. As a result, the weight of the filled, upright container is distributed over a relatively large area. This measure together with the stiffness-increasing features in the form of the grooves and the panel-like projections creates the conditions for a reduction in the wall thickness, without suffering from the overpressure resistance or compression strength of the plastic container. Thus, for example, the container weight can be reduced by up to 2 g, for example from 17.2 g to 15.2 g, without there being any appreciable impairment of the required strengths. By appropriate production methods can be achieved that the wall thickness of the plastic container, for example, equal to or less than 0.2 mm. Except this may be a closure thread in the neck area. Such plastic containers are preferably made from heated preforms in a stretch blow molding process.

According to one embodiment of the invention, the grooves of the plastic container can extend substantially along the longitudinal axis in the laterally raised edge region of the bottom portion. In this way, the rigidity or stability of the container portion can be additionally increased.

In a further embodiment of the invention, the first number of grooves and the second number of panel-like projections may be different from each other. Due to the second number of panel-like protrusions, the rigidity of the concave portion of the bottom portion can be independent of the rigidity of the raised portion Randbereich be specified. In most cases, however, the first number of grooves and the second number of panel-like projections will be the same in order to give the plastic container, in particular the container bottom, a pleasing appearance.

In a variant of the invention, the concave portion of the container bottom can enclose a central dome extending into the container interior. The central dome has a much greater curvature than the dome-shaped concave portion. As a result, the rigidity of the now annular concave portion is further increased. In the production of the plastic container in a stretch-blown process, the apex area of the central dome serves as an attachment for a mandrel. As a result, overly rapid cooling and freezing of the bottom section in the contact area with the stretching mandrel can be avoided.

For manufacturing reasons, it proves to be expedient if the panel-like projections each end before a transition of the concave portion to the central dome. In particular, this also prevents material accumulation during the biaxial stretching process.

To achieve the required flexibility, it is expedient if an axial height bridged between the concave section and the standing surface by means of the stepped transition region is 0.2 mm to 10 mm, preferably 0.5 mm to 5 mm, particularly preferably 1 mm. A radial extension of the stepped transition region extending substantially transversely to the longitudinal axis of the plastic container is approximately 0.2 mm to 10 mm, preferably 0.5 mm to 5 mm, particularly preferably 1.3 mm.

To reinforce the bottom section, the grooves extending from the stepped transition region into the laterally raised edge region may have a depth which is 0.5 mm to 5 mm, preferably 1 mm to 3 mm, particularly preferably 2 mm.

In a further embodiment of the invention, the grooves may have a certain depth which is equal to or greater than an axial height of the stepped transition region extending between the concave portion and the standing surface. As a result, it can be brought about that the groove bottom, viewed in the direction of the pouring opening, is lower than the outwardly facing surface of the concave portion. Thus, the grooves can extend into the concave portion and thus further enhance the stability of the container bottom. With this embodiment, the footprint and the graded transition region are divided into individual segments.

For the reinforcement of the bottom portion, it may also be advantageous if the grooves have a Öffhungswinkel which is 20 ° to 50 °, preferably 27 ° to 43 °, particularly preferably 35 °.

The panel-like projections serve to further stiffen the concave portion of the container bottom. They can have a relatively large surface area and have a greatest extent in the circumferential direction, measured in the vicinity of the stepped transition, which is 2 mm to 10 mm, preferably 5 mm to 8.5 mm, particularly preferably 7.25 mm. The panel-like protrusions may have a maximum protrusion with respect to the concave portion, which is 0.5 mm to 5 mm, preferably 1.3 mm to 3.8 mm, particularly preferably 2.4 mm.

A balanced distribution of the total weight of the filled plastic container results already in that a plastic container which has a substantially circular cross-section at least within the laterally raised edge region has a standing surface with a median stand diameter, the 60% to 80% of an outer diameter of the bottom portion at the transition of the raised edge region to the container body. The footprint can have a radial width that is 5% to 15% of their average standing diameter.

The grooves do not have to end exactly at the graduated transition. You can also have a extending in the direction of the longitudinal axis of the plastic container outlet, which projects from 0.2 mm to 4 mm into the concave portion. This can also contribute to the stiffening of the concave section.

For the stability of the plastic container, it may prove advantageous if the first number of grooves is odd. In an exemplary embodiment variant of Invention, the bottom portion of the plastic container having seven grooves which are distributed substantially uniformly over the circumference of the bottom portion.

The plastic container may have different cross sections. Preference is given to regular cross sections, such as circular or substantially square cross sections. Such plastic containers are used for example for the storage of edible oil, in which the oxygen is displaced by nitrogen after filling. As a result, in the filled plastic container, a slight overpressure of up to 1.5 bar, preferably from 0.3 to 0.5 bar, generated compared to the ambient pressure.

The plastic container can be made in an extrusion blown from a continuously or discontinuously extruded plastic tube. Because of the higher achievable stretch hardening, the plastic container formed according to the invention is preferably produced in a stretch blow molding method from a previously produced elongate preform. The production of the preform or preform can be made to different. For example, injection molding, flow molding or extrusion blow molding are used for this.

Further advantages and features of the invention will become apparent from the following description of the method with reference to the non-scale, schematic drawings:

Fig. 1 shows a side view of a proposed plastic container;

Fig. 2 is a perspective view of a bottom portion of the plastic container;

Fig. 3 shows another perspective view of the bottom portion;

Fig. 4 is a plan view of the bottom portion of the plastic container;

Fig. 5 shows a side view of the bottom portion of the plastic container; and

Fig. 6 shows an axially sectioned view of the bottom portion of the plastic container. In the following description of the figures, the same reference numerals designate the same components or features.

The plastic container 1 has a container body 2 with a longitudinal axis, at the one longitudinal end of which a container neck 3, which has a pouring opening 4, adjoins a plastic container 1, in particular a plastic bottle. At the other longitudinal end of the container body 2 includes a bottom portion 5, which comprises a container bottom 6 with a base 7 and a side raised edge portion 8, which merges into the container body 2. The illustrated plastic container 1 is, for example, a plastic bottle for edible oil. Such plastic containers 1 are usually produced in a stretch blow molding process from a prefabricated elongated preform or preform having a substantially circular cross section. The preform is usually manufactured in an injection molding process. It can also be produced, for example, in a flow molding process or in an extrusion blow molding process. After filling of the edible oil nitrogen is introduced with positive pressure in the plastic container 1 before closing to displace the oxygen. This results in the filled, sealed plastic container, a slight overpressure compared to the ambient pressure, which may be up to 1.5 bar, preferably about 0.3 bar to 0.5 bar.

Fig. 2 shows a perspective view of the bottom portion 5. This comprises the container bottom 6 and the side raised edge portion 8, which merges into the container body 2. The container bottom 6 extends from a central region of the bottom section 5 to the standing surface 7 and encloses this with. The container bottom 6 comprises a dome-shaped, curved into the container interior concave portion 9, which encloses an annular space in an inner space bounded by the container body 2 central dome 13. A substantially annular formed, axially projecting stepped transition region 10 connects the concave portion 9 with the footprint 7. The stepped transition region 10 and the footing 7 are in the illustrated embodiment of a first number, for example seven, substantially uniformly over the circumference of the bottom portion 5 distributed grooves 1 1 interrupted, which is substantially radially in the side raised edge portion 8 of the Floor section 5 extend. As a result, the base 7 and the stepped transition region 10 are divided into individual segments. The grooves 1 1 further extend into the dome-shaped concave portion 7. The kalottenformige concave portion 7 of the container bottom 6 has a second number of panel-like projections 12, extending from a transition of the concave portion 7 in the central dome 13 approximately radially to extend graduated transition section 10 and end shortly before. The panel-like projections 12 in the concave portion 7 are each arranged substantially centrally between two grooves 11. Accordingly, in the illustrated embodiment, the first number of grooves 11 and the second number of panel-like projections 12 are the same size.

The stepped transition region 10 has a certain flexibility and fulfills for the dome-shaped concave portion 9 a kind of hinge function or Federfuktion. If the inside of the container is excessively high, the concave portion 9 can be pressed radially and axially outwards within predefined limits, whereby radial and axial deformation of the container body 2 can be avoided by the spring function of the stepped transition region 10. The grooves 11 limit the flexibility of the stepped transition region 10 and give the container bottom 6 in turn a greater rigidity. They also ensure an increase in rigidity in the area of the base 7 and in the side raised edge region 8. The combination of the listed features of the bottom section 5 on the one hand leads to the desired limited deformability of the container bottom 6 and on the other hand increases the rigidity of the same. By a corresponding first number and the shape of the grooves 11, a corresponding second number and shape of the panel-like projections 12 and a corresponding shape of the stepped transition region 10, the deformability and the rigidity of the bottom portion 5 can be predetermined. As a result, the conditions have been created for reducing the wall thickness of the plastic container without having to accept appreciable losses in terms of the mechanical strength of the bottom section 5.

FIG. 3 shows a further perspective view of the bottom section 5 for explaining the geometric dimensions of the stepped transition region 10 and the grooves 11. The stepped transition region 10 connects the dome-shaped concave portion 9 with the footprint 7. In this case, the stepped transition region 10 is connected to the dome-shaped concave portion 9 with a first circumference and to the base 7 with a second circumference opposite the first circumference. A bridged by the stepped transition region 10 axial height is 0.2 mm to 10 mm, preferably 0.5 mm to 5 mm, more preferably about 1 mm. It should be noted that the graded transition region 10 has at least one step. However, it may also include two or more stages. The grooves 11 extending from the graded transition region 10 into the raised edge region 8 of the bottom section 5 each have a depth t which is 0.5 mm to 5 mm, preferably 1 mm to 3 mm, particularly preferably 2 mm. In this case, the grooves 11 have an opening angle α, which is 20 ° to 50 °, preferably 27 ° to 43 °, particularly preferably 35 °. The panel-like projections provided with the reference numeral 12 have over the concave portion 9 a maximum axial projection 1, which is 0.5 mm to 5 mm, preferably 1.3 mm to 3.8 mm, particularly preferably 2.4 mm.

From the plan view of the bottom section 5 shown in FIG. 4, it can be seen that the stepped transition region 10 has a radial extension r which is approximately 0.2 mm to 10 mm, preferably 0.5 mm to 5 mm, particularly preferably 1.3 mm. The panel-like projections 12 in the concave portion 9 widen from the central dome 13 toward the stepped transition portion 10 and have at their widest point, adjacent to the stepped transition region 10, a width w which is about 2 mm to 10 mm, preferably 5 mm 8.5 mm, more preferably 7.25 mm. The standing surface 7 has an average standing diameter d, which amounts to 60% to 80% of an outside diameter D of the bottom section 5 at the transition of the raised edge region 8 to the container body 2. The base can have a radial width b, which is about 5% to 15% of its average diameter d. 4 further shows that the grooves 11 do not have to end exactly on the stepped transition region 10. They may also have an outlet 14 extending to the central dome 13, which protrudes into the concave portion 9 about 0.2 mm to 4 mm. This can also contribute to the stiffening of the concave portion 9. According to the illustrated embodiment, the bottom portion 5 has an odd number of grooves 11 and panel-like projections 12. In particular, the illustrated embodiment has seven grooves 11th on, which are approximately evenly distributed over the circumference of the bottom portion 5. Accordingly, seven panel-like projections 12 are formed in the concave portion 9, which are each arranged substantially centrally between two adjacent grooves 11.

Fig. 5 shows a side view of the bottom portion 5. The outer diameter at the transition of the raised edge portion 8 of the bottom portion 5 to the container body 2 is in turn provided with the reference symbol D. The average diameter of the base 7 carries the reference numeral d.

The axial sectional view of the bottom portion 5 in Fig. 6 shows the central dome 13, which extends from the concave portion 9 in the container interior. The axial extent of the central dome 13 corresponds approximately to an axial length of the raised edge portion 8 of the bottom portion 5. The panel-like projections bear the reference numeral 12, the grooves are provided with the reference numeral 11.

The bottom portion 5 of the plastic container 1 formed according to the invention is designed such that it withstands slightly elevated internal pressures of up to 1.5 bar relative to the ambient pressure. Exceeding the slightly increased internal pressure due to higher ambient temperatures can be compensated by the limited flexible connection of the concave portion 9 of the container bottom 6. As a result, deformations of the container body 2 can be avoided. The inventive combination of the features of the bottom portion 5, the conditions are created to reduce the wall thickness of the plastic container, in particular in its bottom portion 5, without thereby have to take a significant loss in terms of strength, in particular the rigidity of the plastic container in purchasing. As a result, for example, the weight of known plastic containers, especially plastic bottles, for the storage of edible oil from originally 17.2 g to 15.2 g can be reduced.

It is understood that the invention is not limited to the illustrated embodiment of a plastic container, in particular a plastic bottle for the storage of edible oil. The inventive combination of features in the formation of the plastic container, in particular its bottom portion, is available in different Kind of plastic containers of advantage. Such plastic containers may have different cross sections in the bottom section. Preference is given to regular cross sections, such as circular or substantially square cross sections. The plastic container can be produced in an extrusion blown process from a continuously or discontinuously extruded plastic tube. Because of the higher achievable stretch hardening, the plastic container formed according to the invention is preferably produced in a stretch blow molding method from a previously produced elongate preform. The preform or preform can be manufactured in different ways. For example, injection molding, flow molding or extrusion blow molding are used for this.

Claims

claims

1. plastic container, in particular for the storage of liquid products under a slight overpressure, with a longitudinal axis extending along a container body (2), at one longitudinal end of a container neck (3) adjoins, which is equipped with at least one Ausgiessöffhung (4), and connected to the other longitudinal end of a bottom portion (5) having a container bottom (6) and a laterally raised edge portion (8) which merges into the container body (2), characterized in that the container bottom (6) in a direction of the container body (2) limited interior of the container curved concave portion (9) whose circumference is connected via an axially projecting stepped transition region (10) with a base (7), which opens into the laterally raised edge portion (8) that the footprint ( 7) and at least a portion of the stepped transition region (10) of a first number of grooves (1 1) are interrupted, and that in the concave portion (9) a second number of panel-like projections (12) is formed, which extend substantially between the stepped transition region (10) and the longitudinal axis and in front of the stepped transition region (10). end up.

2. Plastic container according to claim 1, characterized in that extending the grooves (1 1) in the laterally raised edge region (8) of the bottom portion (5).

3. Plastic container according to claim 1 or 2, characterized in that the first number of grooves and the second number of panel-like projections are different from each other.

4. Plastic container according to one of the preceding claims, characterized in that the concave portion (9) of the container bottom (6) enclosing a in the container interior central dome (13) encloses.

5. Plastic container according to claim 4, characterized in that the panel-like projections (12) each end before a transition of the concave portion (9) to the central dome (13).

6. Plastic container according to one of the preceding claims, characterized in that between the concave portion (9) and the base surface (7) by means of the stepped transition region (10) bridged axial height (s) 0.2 mm to 10 mm, preferably 0.5 mm 5 mm, more preferably 1 mm.

7. Plastic container according to one of the preceding claims, characterized in that the stepped transition region (10) has a substantially radially extending extent (r), which is 0.2 mm to 10 mm, preferably 0.5 mm to 5 mm, particularly preferably 1.3 mm ,

8. Plastic container according to one of the preceding claims, characterized in that the grooves (11) have a depth (t) which is 0.5 mm to 5 mm, preferably 1 mm to 3 mm, particularly preferably 2 mm.

9. Plastic container according to one of the preceding claims, characterized in that a depth (t) of the grooves (11) is equal to or greater than a height (s) of between the concave portion (9) and the standing surface (7) extending stepped Transition area (10).

10. Plastic container according to one of the preceding claims, characterized in that the grooves (1 1) have a Publ opening angle (a), which is 20 ° to 50 °, preferably 27 ° to 43 °, particularly preferably 35 °.

11. Plastic container according to one of the preceding claims, characterized in that the panel-like projections (12) in the vicinity of the stepped transition region (10) measured largest extent (w) in the circumferential direction, the 2 mm to 10 mm, preferably 5 mm to 8.5 mm, more preferably 7.25 mm.

12. Plastic container according to one of the preceding claims, characterized in that the panel-like projections (12) relative to the concave portion (9) have a maximum projection (1), 0.5 mm to 5 mm, preferably 1.3 mm to 3.8 mm, particularly preferably 2.4 mm.

13. Plastic container according to one of the preceding claims, characterized in that the standing surface (7) has a width substantially transversely to the circumferential direction extending width (b), which is 0.1 mm to 5 mm, preferably 0.15 mm to 1 mm, more preferably 0.3 mm.

14. Plastic container according to one of the preceding claims, characterized in that the grooves have an extending in the direction of the longitudinal axis of the outlet (14), the 0.2 mm to 4 mm in the concave portion (9) protrudes.

15. Plastic container according to one of the preceding claims, characterized in that the first number of grooves (11) is odd.

16. Plastic container according to one of the preceding claims, characterized in that the bottom portion (5) has seven grooves (1 1), which are distributed substantially uniformly over the circumference of the bottom portion (5).

17. Plastic container according to one of the preceding claims, characterized in that the plastic container is produced in a stretch blow molding from a previously produced elongated preform.