CZ299585B6 - Container having pressure responsive panels - Google Patents

Abstract

In the present invention, there is disclosed a container (1), suitable as a hot-fill container, including at least one controlled deflection flex panel (3) which may invert and flex under pressure, such as hot-fill conditions, to avoid deformation and permanent buckling of the container (1) wherein the longitudinal and transversal dimensions defining the surface of the flexible panel (3) relative to the container (1) longitudinal axis and the flexible panel has a portion (5) projecting from the plane thereof wherein said flexible panel (3) includes an adaptable initiator portion (8) projecting longitudinally from said adaptable portion (5) whereby the camber of said adaptable initiator portion (8) is in a lesser extent if compared with that of said adaptable portion (5) and both the portions (5, 8) merge longitudinally with the flexible panel (3) in a curvature progressively increasing from the adaptable initiator portion (8) into said adaptable portion (5) so that said adaptable initiator portion (8) can deflect inwards and change the extent in deflection of the adaptable portion (5) in response to change in pressure and thus to cause a gradual reduction of the extent of deflection of said adaptable portion (5) in response to the increase of pressure change within the container (1).

Description

Technical field p

The invention relates to a vessel with pressure-adaptable panels or plates, in particular a polyester vessel capable of being hot-liquid-capable and an improved wall construction of the vessel.

BACKGROUND OF THE INVENTION

When filled with hot liquid, a considerable and complex mechanical stress is exerted on the vessel structure due to the thermal stress, the hydraulic pressure during filling and immediately after closing and the vacuum during liquid cooling.

The thermal stress affects the vessel walls when pouring hot liquid. Due to the hot liquid, the vessel walls soften and then shrink unevenly, causing the vessel to deform. The polyester must therefore be heat treated for molecular changes. to form a vessel with thermal stability.

Pressure and stress are applied to the side walls of the vessel resistant to heat during filling, and also for a considerable time thereafter. When the container is filled with hot liquid and closed, it is subject to initial hydraulic pressure and increased internal pressure. When cooling the liquid and air in the space below the closure, this thermal reduction in volume results in partial exhaustion of air from the vessel. The vacuum generated by cooling tends to mechanically deform the vessel walls.

U.S. Pat. No. 5,178,290 discloses indentations for reinforcing plate surfaces.

U.S. Pat. No. 5,238,129 discloses a further structure of circular rib reinforcement which in this case also extends horizontally in the strips above, below and outside the plate surfaces of the hot liquid filled bottle.

In addition to the need to strengthen the vessel against thermal stress and vacuum, there is a need to cope with the initial hydraulic pressure and increased internal pressure exerted on the vessel by pouring hot liquid and then closing the lid. l im pressurizing the side wall of the container. 35 The heat plates will be pushed outwards, which may cause the vessel to deform.

U.S. Pat. No. 4,877,141 discloses a plate construction that conforms to an initial natural outward curvature due to internal hydraulic pressure and temperature, followed by an inward curvature due to the vacuum generated during cooling. It is important to maintain a relatively flat plate profile, but with a slight displacement of the central portion to strengthen the plate, but which does not prevent the plate from moving radially inwards or outwards. However, since the plate is generally flat, the range of movement in both directions is limited. It does not include plate ribs that increase the flexibility, as this would prevent the outer and inner return movement of the plate as a whole.

U.S. Pat. No. 5,908,128 discloses another resilient plate which has responded to hydraulic pressure and temperature induced forces after filling. A relatively conventional design of a hot liquid container, particularly a container suitable for pasteurization, is described. The claims define that in the pasteurization process there is no need to prepare the container for heat before filling, since a cold liquid is introduced which is heated only after closing the lid. Concave plates are used to compensate for pressure changes. To provide flexibility in a radially outward direction of movement followed by a radially inward direction of movement, the plates are kept in a shallow inward bend to accommodate varying internal pressure and temperature in the pasteurization process. Increasing the temperature after closure, which is maintained for a period of time, will cause the platen material to soften, thereby giving 55 inwardly curved plates more flexibility in the application of force. However, it was found too

C7. 299585 B6 a large curvature would prevent this. Permanent deformation of the plates when deflected in the opposite direction is prevented by adjusting the shallow deflection and softening the material under the influence of heat. The amount of force transmitted to the vessel walls is therefore determined again based on the degree of possible bending of the plates, as is the case with a standard hot liquid bottle. However, the deflection rate is limited,? because it is necessary to maintain a shallow curvature of the radial profile of the plates. The construction of the bottle is thus strengthened in various standard ways.

U.S. Pat. No. 5,303,834 discloses a further resilient plate that can be moved from a convex to a concave position by forming a "shrinkable" container. The vacuum itself cannot reverse the position of the plates, but the plates can be turned manually. When the compressive force is released, the plates will automatically return to their original shape because a large force must be applied to maintain the inverted position, which must be maintained manually. Permanent deformation of the slab caused by initial convex deflection can be avoided by using a group of longitudinal bend points.

U.S. Pat. No. 5,971,184 discloses further " resilient plates which can be moved according to the claims from a first convex position to a second, concave position by forming a hand-gripping bottle with two large flat side walls. Each plate comprises a knurled central portion that can be turned to the opposite position. A container of this type with two large flat opposite walls differs in the vacuum stability of the hot liquid filled containers, which are intended to maintain a generally cylindrical shape when the vacuum is applied. The enlarged side walls are subject to greater suction. by which they are drawn into the concave shape more strongly than in the case of smaller plates, as is the case with the standard six-plate construction on a predominantly cylindrical vessel. The design of the container increases the force applied to each of the two plates, thereby increasing the bending force.

Nevertheless, it is still necessary to maintain the convex region of the plates in a relatively flat shape, otherwise it would not be possible to draw the plate under vacuum into the desired concave shape. The need to maintain a shallow deflection allowing sufficient flexibility is previously described in U.S. Patent No. 5,303,834 and U.S. Patent No. 5,908,128. This in turn limits the amount of vacuum that is released before the walls of the container are subject to stress. Furthermore, it is generally considered impossible for a shape that is convex in the longitudinal and horizontal planes to be reversed in any way unless the convex curvature is reasonably shallow. Further, the plates cannot return to their original convex position when the vacuum is released by removing the closure if they have some pronounced convex deflection.

In the best case, the plate deforms under the force and remains in the new inverted position. The plate will then no longer be able to be reversed in the opposite direction, as the effect of the heat of the liquid on the softening of the material will cease and the amount of ambient pressure will not be sufficient for this. Neither will the shape memory that the plastic was characterized before it collapsed into a concave position. IJS 5,908,128 has previously described the formation of longitudinal ribs to prevent this permanent deformation that occurs when the plates are bent from a convex position to a concave. The same finding regarding irreversible deformation is also disclosed in U.S. Patent 5,303,834

US 4,877,141 also shows that if the plates are to be interwoven against their natural curvature, they must be kept in a relatively flat shape.

A fundamental principle of the failure of the prior art containers is the irreversible deformation of the container structure due to the weak design under the vacuum of the container, especially when the weight of the container is reduced to gain a competitive advantage on the market.

The invention, on the other hand, allows greater bending of the side walls on which the negative pressure is applied. to more easily accommodate the pressure applied to the container. 1, the aforementioned reinforcing ribs of various types and locations may be used to compensate for any unavoidable excess pressure due to ambient forces that would bend the vessel walls to a new " pressure-adapted " shape.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to overcome or at least alleviate these problems with currently available containers, or at least to offer users a suitable choice.

Other objects of the invention will become apparent from the following description.

SUMMARY OF THE INVENTION An object of the present invention is a liquid-filled container having at least one flexible deflection panel 10 to compensate for pressure changes induced in said container, wherein the longitudinal and transverse dimension defining the area of the flexible panel is relative to the longitudinal axis of the container. its surface, with the flexible panel having an adaptive initiation region extending longitudinally from the adaptive region, wherein the convexity of the adaptive initiation region is less than that of the adaptive region and both regions coincide longitudinally with the flexible panel in curvature gradually increasing from the adaptive initiation region to the adaptive region that the adaptive initiation region may bend inwardly and wherein in response to pressure changes the deflection rate changes and causes a gradual reduction of the deflection rate of the adaptive region in response to the increasing change nu pressure in the vessel.

Preferably, the adaptable region extends outward in a transverse direction with respect to the longitudinal axis of the container.

Preferably, the bending of the adaptive region results in a reduction in the external curvature of its external arch.

Preferably, the adaptive initiation region has an outwardly directed curvature that continuously passes into the adaptive region.

Preferably, the adaptive initiation region has an inwardly directed curvature that continuously passes into the adaptive region.

3 (1

Preferably, the extent of the surface varies along the container axis.

Preferably, the adaptive initiation region varies in a transverse diverging range along the longitudinal axis of the vessel.

Preferably, the adaptable region varies in a transversely diverging range along the longitudinal axis of the container.

Preferably, the adaptive initiation region is reversed by reversing its curvature in response to a vacuum change within the vessel.

Preferably, the adaptive region is reversed by reversing its curvature in response to a vacuum change within the container.

Preferably, the container is adapted to be filled with a liquid having a temperature above room temperature, wherein the flexible panel is adapted to reverse in after a change in internal pressure during the temperature change of the liquid, with the adaptive initiation region adapted to reverse with respect to its direction. causes the curvature of the adaptive region to be reversed with respect to the curvature direction thereof.

Preferably, the flexible panel is adapted to deflect inwardly after the internal pressure has dropped during liquid cooling. Preferably, the deflection is formed outwardly with respect to the surface.

Preferably, the flexible panel is adapted to deflect outwardly in use after the internal pressure has increased during heating of the liquid. Preferably, the deflection is formed inwardly with respect to the surface.

- 3 GB 299585 B6

Preferably, the container comprises a plurality of resilient panels spaced about its longitudinal axis.

Preferably, each flexible panel comprises one or more central adaptive initiation regions 5 and a pair of adaptive regions extending from the adaptive initiation region towards the opposite longitudinal ends of the flexible panel,

Preferably, the adaptive initiation region is located closer to the center of the flexible panel having first and second adaptive regions extending longitudinally away from the adaptive initiation region, wherein the first adaptive region extends toward one end of the flexible panel and the second adaptive region extends toward the opposite end of the flexible panel.

Preferably, the vessel is adapted to be filled with liquid at a temperature above room temperature, with the adaptive initiation region and / or the adaptive region having a bulge that varies in a transverse diverging direction along the axis of the vessel.

Preferably, the container has a pair of substantially inflexible regions between which an adaptive initiation region and an adaptive region are guided, wherein the flattened region sc extends between the inflexible regions to form an end of the adaptive initiation region.

Preferably, the adaptive initiation region and / or the adaptive region contact at the apex and provide a flexible panel made in two parts.

Preferably, the adaptive region is positioned in the direction of one longitudinal end of the resilient panel and the adaptive initiation region is positioned in the direction of the opposite end of the flexible panel.

Preferably, the adaptive initiation region extends from the surface to a lesser extent than the adaptive region.

Preferably, the adaptive initiation region is positioned closer in the direction of one longitudinal end of the flexible panel than the adaptive region.

Other aspects of the invention will become apparent from the following description, which is given by way of example only, and with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a front view of a container according to one embodiment of the invention; Figure 2a shows a front view of the surface of the container panel of Figure I.

Figure 2b shows a side view of the panel surface of Figure 2a.

Figure 3 shows a side view of the inverted surface of the panel of Figure 2a.

Figures 4a-c schematically show a cross-section of the container of Figure 1 sequentially along line A-C, unless the panel faces are reversed.

Figures 5a-c schematically show cross-sections of the container of Figure 1 sequentially along lines A-C. when panel faces are reversed.

Figures 6a-c show front and rear views of another embodiment of a panel surface.

Figure 7a shows a front view of another embodiment of a panel surface.

-4 CZ 299585 B6

Figures 7b, c show side views of the panel surface of figure 7a in an inverted and inverted position.

Figure 8a shows a front view of another embodiment of a panel surface.

Figures 8b-d show side views of the panel surface of Figure 8a in an inverted, partially inverted and inverted position.

Figures 9a-c and figures d-f showing schematic cross-sections through successive lines corresponding to the letters A C of the container of Figure I. having a different panel area in the inverted and inverted positions.

DETAILED DESCRIPTION OF THE INVENTION

In Fig. 1, according to a preferred embodiment of the invention, a container, generally indicated 6, having a main side wall 2 of generally cylindrical shape.

The vessel 1 is capable of adapting to pressure and is in particular a vessel for filling with a hot liquid at a temperature above room temperature. The container 1 may be formed in a curved form of polyester or other plastic, eg, heat treated polyethylene target phthalate (PET). The lower part of the side wall 2 comprises a plurality of vertically oriented longitudinal vacuum spring panels 3, which are located around the periphery of the container 1, separated from each other by smooth longitudinal flat areas 4. Each panel 3 may have a generally rectangular shape and adapted to fill the container 8 and the subsequent cooling of the liquid curved inwards. During the process, the vacuum flexible panels 3 behave in such a way. that they equalize the vacuum caused by the hot liquid.

Figure 2a shows the vacuum flexible panel 3 of the container 1. The vacuum flexible panel 3

3t) comprises at least one connection region 7 which connects the adaptation region 5 with the flat regions 4. The adaptation region 5 comprises an adaptation initiation region 8 which controls the connection of the adaptation region 5 and the connection region 7. Preferably, the connection region 7 can be relatively easily under vacuum and the adaptive initiation region 8 will tilt the adaptive region 5 by reversing and then inwardly bending. Thus, a much larger volume of vacuum flexible panels 3 will be exhausted than with existing flexible panels. Thereafter, the vacuum is reduced substantially more than with existing containers, and therefore the walls of the container will be subject to a substantially lower pressure.

The connecting region 7 preferably allows to set a radius from the center of the container i to the edge of the flexible panel 3 (inside the connecting region 7) independently of the radius at the edge of the flat regions 4 (the outer boundary around the connecting region 7). Thus, the connecting region 7 will allow for the independent addition of the flat region 4 on one side and the addition of the flexible panel 3 and its optimization for deflection on the other side. The connecting area 7 compensates for any circumferential radius differences between the two structures.

The boundary 8a between the adaptive initiation region 8 and the remainder of the adaptive region 5 is shown as being strongly arcuate in the circumferential direction of the flexible panel 3.

The degree of arcuate or protrusion of the adaptive initiation region 8 relative to the plane

5 (even delimited by the median longitudinal axis of the container 1 is substantially smaller than the amount of deflection 1 or projection of the adaptive region 5, which causes greater sensitivity to vacuum. The adaptive initiation region 8 further comprises a tip 9 which is predominantly flat and therefore most sensitive to vacuum. that is, the container 6 will be subjected to a negative pressure, the vacuum module 3 may bend at the end 9, then the deflection and reversal of the entire adaptive initiation region 8 will be followed, and then the inverted adaptive region 5 will proceed.

The concave element. In this embodiment, however, the projection of the concave region relative to the bush defined by the central longitudinal axis of the container will be less than the projection of the remainder of the adaptive region 5.

Importantly, in response to a gradual reduction in the volume of the container 1 during cooling, the reversal of the adaptive region 5 can continue to be uniformly opposed to the plate which "collapses between the two states." Due to the gradual deflection of the adaptive region 5 to the inverted position and from the inverted position in response to a relatively small pressure difference compared to the plates that "collapse", less force will be transmitted to the side walls of the container 1. This makes it possible to use a smaller amount of material in the construc- tion of the container, thus making production less expensive. As a result, fewer load failures can be expected for the same amount of material.

Moreover, the reduced pressure difference required to reverse the adaptive region 5 allows a larger number of flexible panels 3 to be contained in a single container 1. The elastic panel 3 may also not be large, although low vacuum is sufficient to deflect the panel 3. Thus, the flexible panels 3 need not be large or need to reduce their number in the container 1, which allows for greater flexibility in the construction of the container L

Figure 2b shows a section along line DD of Figure 2a. The flexible panel 3 is shown with the adaptive region 5 in the inverted position, with a dashed line indicating the boundary of the adaptive region 5c with the connecting region 7. In a preferred embodiment of the invention, the adaptive region 5 is predominantly arched in radially outward or transverse direction. 6. The connecting region 7c is predominantly U-shaped, where the relative height of the sides IJ determines the relative radius where the flat region 4 and the adaptive region 5 are located. The ending 9 is most sensitive to vacuum as it extends to the smallest extent. ie. has the smallest arcuate deflection in the adaptive region 5.

Figure 3 shows a flexible panel 3 with an adaptive region 5 which is reversed as a result of the vacuum. The end 9 and the adaptive initiation region 8 are first deflected and inverted, thereby pulling the adjacent surface of the adaptive region 5 inwardly. This continues along the adapters 30 of the mating region 5 until the mating region 5 is completely reversed. As shown by the line 5b of the projecting region. The dotted line in Figure 3 shows the edge of the mating region 5 and the dashed line 5a shows the position of the mating region 5 when not.

Importantly, when the vacuum is removed from the container after the closure has been removed, the resilient panel 3 may leave the position it has assumed due to the vacuum and return to its original shape. This may be assisted by a uniform increase in the arcuate curvature from one end of the adaptive region 5 to the other, the arc of curvature gradually increasing from the adaptive initiation region 8. Alternatively, the adaptive region 5 may have a substantially constant increase. When the pressure is released, the adaptive initiation region 8 induces a transverse movement of the resilient panel 3 arched inwardly, which begins by reversing the adaptive initiation region 8, followed by an increased adaptive region 5 without causing irreversible deflection. The vacuum spring panel 3 can be repeatedly turned without significant permanent deformation.

Figures 4a-c show cross-sections of the container I of Figure 1 taken along lines AA, BB and CC, with 45 causing the area 5 in the inverted position. In this preferred embodiment, the adaptive region 5 protrudes increasingly outwardly from the region with the adaptive initiation region 8.

Figures 5a-c show cross-sections of the container 1 of Figure 1 taken along lines AA, BB and CC. with the adaptive region 5 in the fully inverted position 5b due to the applied negative pressure. The area of the adaptive region 5 along the line AA is deflected to a relatively large extent compared to the region closer to the region with the adaptive initiation region 8. The dotted lines 5a in Figures 5a-c indicate the position of the adaptive regions 5 without applying vacuum.

Figure 6a shows a front view of another embodiment of the flexible panel 30 with an adaptive initiation region 80 and a flattened end 90. The connection region 20 of the flexible panel 30 is planar.

Figure 6b shows the flexible panel 30 without applying negative pressure. The adaptive region 50 has a predominantly constant arcuate curvature from the adaptive initiation region 80 in the direction of arrow 6. Figure 6c shows the flexible panel 30 with the adaptive region 50 in a fully inverted position due to the application of vacuum.

Figure 7a shows views of another embodiment of the flexible panel 300. The flexible panel 300 comprises two adaptive regions 500 positioned vertically side by side. The flexible initiator regions 800 are located in two directions from the central end 900 of the initiator regions 800. In this embodiment, the center of the flexible panel 300 is most sensitive to deflection under the influence of vacuum, and thus deflects first. Figures 7b and 7c show successively the flexible panels 300 without applying vacuum and in a fully inverted position.

The dotted line 800a shows the arc deflection boundary between the adaptive initiation region 800 and the remainder of the adaptive region 500.

Figure 8a shows a front view of another embodiment of a flexible panel indicated generally by the arrow 300 '.

The flexible panel 300 'comprises two adaptive regions 500' and 500 positioned vertically side by side with respective adaptive initiation regions 800 'with a central flattened region, terminations 900'. between them. However, unlike the flexible panel 300, the normal position of one of the fit regions 500 is concave and not convex (see FIG. 8b). By applying hydraulic pressure, the concave adaptation region 500 is reversed in the direction shown by the arrow 6a (see FIG. 8c), thereby reducing the pressure on the flat regions 4 between adjacent spring panels 300 '. Once the liquid has cooled, the vacuum causes the two adaptation regions 500 'and 500 to reverse in the direction of arrow 6b (see Figure 8d).

It is valuable that the profile and / or construction of the flexible panels can be changed. For example, as shown in Figure 9, the container 1 may have flexible panels with adaptive regions 5 'including two planar regions 10'. which meet at the apex 11 so as to form an angular plate, i.e. not a curved plate. Figures 9a-e show cross-sections of lines A A. BB and CC of the container from Figure 1 with at 3 (> impressive areas 5 ') Figures 9d-f show inverted positions of the adaptive areas 5' of Figures 9a-e, In addition or otherwise, the elastic panels 3 of all embodiments may be positioned transversely to the longitudinal axis of the container 1, i.e. not vertically, as shown, for example, in Figure I.

Thus, a pressure-adaptable container is formed which comprises flexible panels which allow for a large change in volume and thus in the contents of the container, thereby reducing the pressure applied to the walls. Consequently, less material is required to maintain the integrity of the container, making it less expensive to manufacture.

Where reference has been made in the preceding description to particular parts or components of the invention to which known equivalents exist, these equivalents are also included herein as if they were specifically delineated.

Although the invention has been described by way of example and with reference to possible embodiments, it should be understood that modifications or improvements may be made thereto without departing from the scope of the invention as defined in the appended claims.

Claims (3)

PATENT CLAIMS 1. A pressure-adaptable span receptacle suitable for liquid filling having at least one flexible deflection panel (3) for compensating for pressure changes induced in the receptacle (I), the longitudinal and transverse dimensions defining the area of the flexible panel (3) is related to the longitudinal axis of the container (1) and the flexible panel (3) has an adaptive region (5) extending from its surface, characterized in that the flexible panel (3) has an adaptive initiation region (8) extending longitudinally from the adaptive region ( 5), wherein the camber of the adaptive initiation region (8) is smaller than the camber of the adaptive region (5) and both regions (5, 8) coincide longitudinally with the flexible panel (3) in curvature gradually increasing from the adaptive initiation region (8) to the adaptive region (5) such that the adaptive initiation region (8) can deflect inwards and vary the deflection rate and cause progressively reduce the degree of deflection of the adaptive region (5) 15 in response to an increasing pressure grain in the vessel (1). Container according to claim 1, characterized in that. that the adaptive region (5) is arched outwards in a transverse direction with respect to the longitudinal axis of the container (1). Container according to claim 1 or 2, characterized in that the deflection by the adaptive region (5) results in a reduction in the external curvature of its external camber. Container according to claims 1, 2 or 3, characterized in that: that the adaptive initiation region (8) has an outwardly directed curvature which continuously passes into the adaptive region (5). Container according to claims 1, 2 or 3, characterized by. wherein the adaptive initiation region (8) has an inwardly curvature which continuously passes into the adaptive region (5). Container according to claim 1, characterized in that the range of curvature of the panel surface 30 (3) varies along the axis of the container (1). Container according to claim 1, characterized in that. that the adaptive initiation region (8) varies in a transversely diverging range along the longitudinal axis of the container (1). A container according to claim 7, characterized in that the adaptive region (5) varies in a transversely diverging range along the longitudinal axis of the container (1). A container according to claim 7, characterized in that. that the adaptive initiation region (8) is reversed by reversing its curvature in response to a vacuum change within the container (1). A container according to claim 9, characterized in that the adaptive region (5) is reversed such that the reverse of its curvature is sc in response to a vacuum change within the container (1). Container according to claim 1, wherein the container (1) is adapted to be filled with a liquid having a temperature of 45 higher than room temperature, wherein the flexible panel (3) is adapted to reverse the change of the internal pressure during the liquid temperature change. wherein the adaptive initiation region (8) is adapted to be inverted relative to the camber direction thereof, thereby causing the adaptive region (5) to be inverted relative to its camber direction. A container according to claim 11, characterized in. The flexible panel (3) is adapted to deflect inwardly after the internal pressure has dropped during cooling of the liquid. 13. A container according to claim 11 or 12. that the deflection is outwardly relative to the panel surface (3). - 8 GB 299585 B6 Container according to claim 13, characterized in. The flexible panel (3) is adapted to deflect outwardly after an increase in internal pressure during heating of the liquid. A container according to claim 11, characterized in. that the deflection is in the inward direction 5 relative to the panel surface (3). Container according to claim 11, characterized in that it comprises a plurality of flexible panels (3) spaced around its longitudinal axis. Container according to claim 11, characterized in that each flexible panel (3) comprises one or more central adaptive initiation regions (8) and a pair of adaptive regions (5) extending from the adaptive initiation regions (8) in the direction of opposite longitudinal the ends of the flexible panel (3). A container according to claim 1, characterized in. wherein the adaptation initiation region (8) is located closer to the center of the flexible panel (3) having first and second adaptation regions (5) extending longitudinally away from the adaptation initiation region (8), the first adaptation region (5) being directed towards one the second flexible region (5) extends in the direction of the opposite end of the flexible panel (3). A container according to claim 18, adapted to be filled with a liquid at a temperature higher than room temperature, characterized in that it comprises: that the adaptive initiation region (8) and / or the adaptive region (5) has a bulge which varies transversely along the axis of the container (1). A container according to claim 19, characterized in that it has a pair of substantially inelastic regions between which an adaptive initiation region (8) and an adaptive region (5) are guided. wherein the flattened region (900 ') extends between the inelastic regions to form the termination of the adaptive initiation region (8). Container according to claim 1, characterized in that the adaptive initiation region (8) and / or the adaptive region (5) contacting at the apex (11) provide a flexible panel (3) formed in two parts. A container according to claim 1, characterized in that. wherein the adaptive region (5) is semi-aligned in the direction of one longitudinal end of the flexible panel (3) and the adaptive initiation region (8) is positioned in the opposite direction of the flexible panel (3). Container according to claim 1, characterized in that the adaptive initiation region (8) projects to a lesser extent from the surface of the panel (3) than the adaptive region (5). Container according to claim 1, characterized in that the adaptive initiation region (8) is positioned closer to one longitudinal end of the flexible panel (3) than the adaptive region (5).