Abstract
The present invention relates to a liquid-tight container comprising a container wall which surrounds a container interior at least in part, wherein: a jacket element and a first end element are connected to one another and each form a portion of the container wall; wherein the jacket element delimits the container interior in a transverse direction extending from the inside to the outside in relation to the container interior, and comprises a rim portion having a first edge; wherein the first end element delimits the container interior at a first end of the liquid-tight container in a longitudinal direction extending along the length of the container, and comprises a further edge which points in the longitudinal direction; wherein the rim portion a. is located at the first end of the container, and b. encloses the further edge counter to the transverse direction from the outside to the inside in such a way that i. the first edge of the jacket element points counter to the longitudinal direction, and ii. the liquid-tight container comprises, at the first end in the transverse direction, a ply sequence comprising A. a first ply of the jacket element, B. a ply of the first end element, and C. a further ply of the jacket element; wherein the rim portion comprises, at least on a side pointing inwards counter to the transverse direction, a plurality of portions of a first type and a plurality of portions of a further type, which portions differ from one another in their thickness in the transverse direction.
The invention also relates to a precursor for producing the liquid-tight container, to a method for producing a liquid-tight container, to the use of a liquid-tight container, and to the use of an ultrasonic generator and/or an ultrasonic sonotrode.
Claims
1. A liquid-tight container, comprising a container wall which surrounds a container interior at least in part; wherein a jacket element and a first end element are connected to one another and each form a portion of the container wall; wherein the jacket element delimits the container interior in a transverse direction extending from the inside to the outside in relation to the container interior, and comprises a rim portion having a first edge; wherein the first end element delimits the container interior at a first end of the liquid-tight container in a longitudinal direction extending along the length of the liquid-tight container, and comprises a further edge which points in the longitudinal direction; wherein the rim portion a. is located at the first end of the liquid-tight container, and b. encloses the further edge counter to the transverse direction from the outside to the inside in such a way that i. the first edge of the jacket element points counter to the longitudinal direction, and ii. the liquid-tight container comprises, at the first end in the transverse direction, a ply sequence comprising A. a first ply of the jacket element, B. a ply of the first end element, and C. a further ply of the jacket element; wherein the rim portion comprises, at least on an inward-facing side counter to the transverse direction, a plurality of portions of a first type and a plurality of portions of a further type; wherein the portions of the first type and the portions of the further type follow one another in a circumferential direction that extends along the further edge; wherein the first ply of the jacket element has a thickness in the transverse direction; wherein the thickness of the first ply is a mathematical function of a position along the circumferential direction; wherein the mathematical function has a plurality of local maxima and a plurality of local minima; wherein each portion of the first type comprises exactly one of the local maxima and each portion of the further type comprises exactly one of the local minima; wherein the thickness of the first ply in each entire portion of the first type is at least 0.7 times a value of the local maximum comprised by the respective portion of the first type; wherein the thickness of the first ply in each entire portion of the further type is at most 1.3 times a value of the local minimum comprised by the respective portion of the further type; wherein each portion of the first type has a first length in the circumferential direction; wherein each portion of the further type has a second length in the circumferential direction; characterized in that each second length is at least 10% of each first length.
2. The liquid-tight container according to claim 1, wherein the value of each local minimum is 10 to 80% of the value of each local maximum.
3. The liquid-tight container according to claim 1, wherein the further edge forms a closed curve with a third length along the circumferential direction; wherein the first end element has a height extending in the longitudinal direction at each point of the closed curve; wherein the rim portion protrudes beyond the further edge at each point of the closed curve such that the rim portion extends from the further edge to the first edge by an overhang length; wherein the overhang length is measured on a side of the rim portion facing away from the first end element; wherein the overhang length along at least 50% of the third length is 30 to 100% of the height.
4. The liquid-tight container according to claim 1, wherein the jacket element is at least partially formed from a first sheet-like material.
5. The liquid-tight container according to claim 4, wherein the first sheet-like material is a first sheet-like composite comprising a first layer sequence; wherein the first layer sequence comprises a first carrier layer.
6. The liquid-tight container according to claim 4, wherein the first carrier layer in the first layer sequence is overlaid with a first polymer inner layer on a side facing the container interior.
7. The liquid-tight container according to claim 5, wherein the first carrier layer in the first layer sequence is overlaid with a first polymer outer layer on a side facing away from the container interior.
8. The liquid-tight container according to claim 7, wherein the first layer sequence between the first carrier layer and the first polymer inner layer comprises a first barrier layer.
9. A precursor for producing the liquid-tight container according to claim 1, the precursor comprising a container wall which surrounds the container interior at least in part; wherein the jacket element and the first end element are connected to one another and each form a portion of the container wall; wherein the jacket element delimits the container interior in the transverse direction, and comprises the rim portion having the first edge; wherein the first end element delimits the container interior at a first end of the precursor in the longitudinal direction, and comprises the further edge; wherein the rim portion is arranged at the first end of the precursor; wherein the first edge and the further edge point in the longitudinal direction; wherein the further edge forms a closed curve with a third length; wherein the first end element has a height extending in the longitudinal direction at each point of the closed curve; wherein the rim portion protrudes beyond the further edge at each point of the closed curve such that the rim portion extends from the further edge to the first edge by an overhang length; wherein the overhang length is measured on a side of the rim portion facing away from the first end element; wherein the overhang length along at least 50% of the third length is 30 to 100% of the height.
10. A method for producing a liquid-tight container, the method comprising as process steps a. providing a precursor of the liquid-tight container, the precursor comprising a container wall at least partially surrounding a container interior; wherein a jacket element and a first end element are connected to one another and each form a portion of the container wall; wherein the jacket element delimits the container interior in a transverse direction extending from the inside to the outside in relation to the container interior, and comprises a rim portion having a first edge; wherein the first end element delimits the container interior at a first end of the precursor in a longitudinal direction extending along a length of the precursor, and comprises a further edge; wherein the rim portion is arranged at the first end of the precursor; wherein the first edge and the further edge point in the longitudinal direction; b. forming the rim portion by contacting it with a forming tool, so that the rim portion encloses the further edge counter to the transverse direction from the outside to the inside in such a way that i. the first edge of the jacket element points opposite to the longitudinal direction, and ii. the precursor or the liquid-tight container obtained therefrom has at the first end in the transverse direction a layer sequence comprising A. a first ply of the jacket element, B. a ply of the first end element, and C. a further ply of the jacket element; characterized in that the forming tool carries out an oscillation with a frequency in a range from 15 to 50 kHz during the forming.
11. The method according to claim 10, wherein the oscillation takes place in a direction that forms an angle of less than 30 with the longitudinal direction and counter to this direction.
12. The method according to claim 10, wherein the forming tool is set into oscillation before contacting the rim portion.
13. A use of the liquid-tight container according to claim 1 for storing or transporting a liquid.
14. A use of a sheet-like composite for producing the liquid-tight container according to claim 1; wherein the jacket element or the first end element or both are at least partially formed from the sheet-like composite.
15. A use a) of an ultrasonic generator to excite the oscillation, or b) of an ultrasonic sonotrode as the forming tool, c) or a) and b) each in the method according to claim 10.
Description
[0286] Unless otherwise indicated in the description or the respective drawing, the drawings show, schematically and not to scale:
[0287] FIG. 1 a schematic representation of a liquid-tight container according to the invention;
[0288] FIG. 2 a schematic cross-sectional view of the container bottom of the liquid-tight container of FIG. 1;
[0289] FIG. 3 a schematic representation of the bottom of the liquid-tight container 100 according to the invention in a view from below;
[0290] FIG. 4 a schematic representation of a liquid-tight container 100 according to the invention, which is not yet closed at its upper end;
[0291] FIG. 5 an exploded view of the liquid-tight container 100 of FIG. 1;
[0292] FIG. 6 a schematic representation of the conditions of the flanging process when connecting the first end element to the rim portion 107 of the jacket element 102;
[0293] FIG. 7 a schematic representation of the sonotrode 600 as used in the process shown in FIG. 6;
[0294] FIG. 8 a schematic representation of a preferred embodiment of the liquid-tight container 100 according to the invention in the rim portion 107 of the jacket element 101;
[0295] FIG. 9 a black and white photographic representation of the bottom of a liquid-tight container 100 according to the invention in a view from below;
[0296] FIG. 10 another black and white photographic representation of the bottom of a liquid-tight container 100 according to the invention in a view from below;
[0297] FIG. 11 a schematic cross-sectional representation of a sheet-like composite 1100;
[0298] FIG. 12 a schematic cross-sectional view at the lower end 105 of a precursor 1200 according to the invention for producing a liquid-tight container 100;
[0299] FIG. 13 a flow chart of a method 1300 according to the invention for producing a liquid-tight container 100.
[0300] FIG. 1 shows a schematic representation of a liquid-tight container 100 according to the invention, the container wall 101 of which is formed in three parts. In each case, a region of the container wall 101 surrounding a container interior 201 (see FIG. 2) is formed by a jacket element 102, a first end element 103, and a further end element 108. Both the jacket element 102 and the first end element 103 consist of the sheet-like composite 1100 shown in FIG. 11. Where the first end element 103 is formed from a circular piece of the sheet-like composite 1100, the jacket element 102 consists of a rectangular cut of the sheet-like composite 1100. Opposite longitudinal edges of this cut are contacted with each other in an overlapping manner and sealed together. The seam thus obtained is referred to as the longitudinal seam 110 of the container 100. The jacket element 102 laterally delimits the container interior 201, based on a length of the liquid-tight container 100. The first end element 103 delimits the container interior 201 in a first direction along a length of the container 100. In addition, the first end element 103, in relation to the length of the liquid-tight container 100, seals the liquid-tight container 100 at a first end 105 that is formed by a container bottom 103. The further end element 108 is a molded part made of plastics material with a circular shape in top view and a central pouring hole. The further end element 108 delimits the container interior 201 in a further direction counter to the first direction. Furthermore, the 100 comprises a closure lid 109. The pouring hole of the further end element 108 is located under this closure lid 109. A pull tab made of aluminum foil coated on both sides with LDPE is sealed over this pouring hole. The further end element 108 closes the liquid-tight container 100 together with the pull at a second end 111 opposite the first end 105 of the container 100, relative to the length of the liquid-tight container 100, which second end is formed by a container head 108. After the liquid-tight container has been opened by tearing off the pull tab, the closure lid 109 provides a means of closing the liquid-tight container 100 again, albeit significantly less tightly. Details of the container bottom 103 designed according to the invention can be seen in FIG. 2.
[0301] FIG. 2 shows a schematic cross-sectional view of the container bottom of the liquid-tight container of FIG. 1. The jacket element 102 delimits the container interior 201 in a transverse direction 104 running from the inside to the outside with respect to the container interior 201 and includes a rim portion 107 with a first edge 202. The first end element 103 delimits the container interior 201 at a first end 105 of the container 100 in a longitudinal direction 106 running along a length of the container and comprises a further edge 203 which points in the longitudinal direction 106. The rim portion 107 is arranged at the first end 105 of the liquid-tight container 100 and encloses the further edge 203 counter to the transverse direction 104 from the outside to the inside in such a way that the first edge 202 of the jacket element 101 points counter to the longitudinal direction 106, and the liquid-tight container 100 has a layer sequence at the first end 105 in the transverse direction 104 which comprises a first ply 801 of the jacket element 102, a ply 802 of the first end element 103, and a further ply 803 of the jacket element 102, as shown in FIG. 8. The rim portion 107 comprises, at least on a side 204 which faces inward counter to the transverse direction 104, a plurality of portions 301 of a first type and a plurality of portions 302 of a further type, as shown in FIG. 3.
[0302] FIG. 3 shows a schematic representation of the bottom of the liquid-tight container 100 according to the invention in a view from below, in which these portions 301 and 302 are shown. The portions 301 of the first type and portions 302 of the further type follow one another in a circumferential direction which runs along the further edge 203, wherein the first ply 801 (shown in FIG. 8) of the jacket element 102 has a thickness 804 in the transverse direction 104. The thickness 804 of the first ply 801 is a mathematical function of a position along the circumferential direction, the mathematical function having a plurality of local maxima and a plurality of local minima. Each portion 301 comprises exactly one of the local maxima and each further portion 302 comprises exactly one of the local minima. The thickness 804 of the first ply 801 in each entire first portion 301 is at least 0.7 times a value of the local maximum included by that first portion 301. The thickness 804 of the first ply 801 in each entire further portion 302 is at most 1.3 times a value of the local minimum included in that further portion 302. As can also be seen from FIG. 3, each portion 301 of the first type has a first length 303 in the circumferential direction and each portion 302 of the further type has a second length 304 in the circumferential direction. The liquid-tight container according to the invention is characterized in that every second length 304 is at least 10% of every first length 303.
[0303] FIG. 4 shows a schematic representation of a liquid-tight container 100 according to the invention, which is not yet closed at its further (upper) end 111. In order to facilitate the folding of the jacket element 102 to close the further end 111, the jacket element 101 has grooves 401 which predetermine the fold lines to be made. By folding along the grooves 401 and sealing the folding surfaces together, a liquid-tight container 100 can be obtained, the head portion of which has a gable-shaped configuration (not shown). FIG. 4 also shows the container bottom cut at the first end 105. This shows that the jacket element 102 completely surrounds the first end element 103 laterally.
[0304] FIG. 5 shows an exploded view of the liquid-tight container 100 of FIG. 1.
[0305] FIG. 6 shows a schematic representation of the conditions of the flanging process when connecting the first end element to the rim portion 107 of the jacket element 102, as described in detail above in the experimental part in the paragraph container production. FIG. 7 shows a schematic representation of the sonotrode 600 as it is used in this flanging process.
[0306] FIG. 8 shows a schematic representation of a preferred embodiment of the liquid-tight container 100 according to the invention in the rim portion 107 of the jacket element 101. According to this embodiment, the further edge 203 forms a closed curve with a third length along the circumferential direction, wherein the first end element 103 has a height 805 extending in the longitudinal direction 106 at each point of the closed curve. The rim portion 107 protrudes beyond the further edge 203 at every point of the closed curve such that the rim portion 107 extends from the further edge 203 to the first edge 202 by an overhang length 806, wherein the overhang length 806 is measured on a side of the rim portion 107 which faces away from the first end element 103 (it therefore corresponds to the length of the dashed line in FIG. 8). Preferably, the overhang length 806 along at least 50% of the third length is 30 to 100% of the height 805.
[0307] FIG. 9 shows a black-and-white photographic representation of the bottom of a liquid-tight container 100 according to the invention in a view from below, in which the portions 301 and 302 are shown. The liquid-tight container 100 shown in FIG. 9 is a container in which the jacket element (and accordingly also the first end element forming the bottom portion) has a substantially triangular cross-section. To produce such a container, a sonotrode 600 is to be used in the flanging process described in FIG. 6, which, in contrast to the circular shape shown in FIG. 7, has a corresponding triangular shape.
[0308] FIG. 10 shows a black-and-white photographic representation of a detail of the bottom of a liquid-tight container 100 according to the invention in a view from below, in which the portions 301 and 302 are again shown. The liquid-tight container 100 shown in FIG. 9 is a container in which the jacket element (and accordingly also the first end element forming the bottom portion) has a substantially circular cross-section.
[0309] FIG. 11 shows a schematic cross-sectional view of a sheet-like composite 1100. From its outer surface 1101 towards its inner surface 1102, this consists of the following layers overlapping each other over their entire surfaces: polymer outer layer 1103, carrier layer 1104, polymer intermediate layer 1105, adhesive layer 1106, and polymer inner layer 1108. Suitable materials and basis weights of the layers are given in Table 1 above.
[0310] FIG. 12 shows a schematic cross-sectional view at the lower end 105 of a precursor 1200 according to the invention for producing the inventive liquid-tight container 100. The precursor 1200 includes a container wall 101 that at least partially surrounds the container interior 201, wherein the jacket element 102 and the first end element 103 are connected to one another and each form a portion of the container wall 101. The jacket element 102 delimits the container interior 102 in the transverse direction 104 and includes rim portion 107 with the first edge 202. The first end element 103 delimits the container interior 201 at a first end 105 of the precursor in the longitudinal direction 106 and comprises the further edge 203, wherein the rim portion 107 is arranged at the first end 105 of the precursor 1200. The first edge 202 and the further edge 203 point in the longitudinal direction 106. The further edge 203 forms a closed curve with a third length, wherein the first end element 103 has a height 805 (shown in FIG. 8) extending in the longitudinal direction 106 at each point of the closed curve. The rim portion 107 protrudes beyond the further edge 203 at every point of the closed curve such that the rim portion 107 extends from the further edge 203 to the first edge 202 by an overhang length 806, wherein the overhang length 806 is measured on a side of the rim portion 107 which faces away from the first end element 103. The overhang length 806 along at least 50% of the third length is 30 to 100% of the height 805.
[0311] FIG. 13 shows a flow chart of a method 1300 according to the invention for producing a liquid-tight container 100. In method step 1301, a precursor 1200 according to the invention, as shown in FIG. 12, is provided. The precursor 1200 includes a container wall 101 at least partially surrounding a container interior 201, wherein a jacket element 102 and a first end element 103 are connected to one another and each form a portion of the container wall 101. The jacket element 102 delimits the container interior 201 in a transverse direction 104 running from the inside to the outside in relation to the container interior 201 and includes a rim portion 107 with a first edge 202. The first end element 103 delimits the container interior 201 at a first end of the 105 precursor 1200 in a longitudinal direction 106 running along a length of the precursor 1200 and includes a further edge 203, wherein the rim portion 107 is arranged at the first end 105 of the precursor 1200 and wherein the first edge 202 and the further edge 203 point in the longitudinal direction 106. In method step 1302, the rim portion 107 is formed by contacting with a forming tool, as shown in FIG. 6. The rim portion 107 encloses the further edge 203 counter to the transverse direction 104 from the outside to the inside in such a way that the first edge 202 of the jacket element 102 points counter to the longitudinal direction 106, and the precursor 1200 or the liquid-tight container 100 obtained therefrom has a layer sequence at the first end 105 in the transverse direction 104 which includes a first ply 801 of the jacket element 102, a ply 802 of the first end element 103 and a further ply 802 of the jacket element 102 (as shown in FIG. 8). During forming, the forming tool executes an oscillation with 10 a frequency in the range from 15 to 50 kHz.
LIST OF REFERENCE SIGNS
[0312] 100 liquid-tight container according to the invention [0313] 101 container wall [0314] 102 jacket element [0315] 103 first end element, preferably container bottom [0316] 104 transverse direction [0317] 105 first end of the liquid-tight container 100 [0318] 106 longitudinal direction [0319] 107 rim portion of the jacket element 102 [0320] 108 further end element, preferably container head [0321] 109 closure lid [0322] 110 longitudinal seam [0323] 111 second end of the liquid-tight container 100 [0324] 201 container interior [0325] 202 first edge of the rim portion 207 [0326] 203 further edge of the first end element 103 [0327] 204 inward-facing side of the rim portion [0328] 301 plurality of portions of a first type [0329] 302 plurality of portions of a further type [0330] 303 first length of the portion 301 of the first type [0331] 304 first length of the portion 302 of the further type [0332] 400 upper rim portion of the jacket element [0333] 401 groove [0334] 600 sonotrode [0335] 601 counter-tool (anvil) [0336] 602 conical sealing surface [0337] 603 first wall of the groove [0338] 604 groove bottom [0339] 605 second wall of the groove [0340] 606 groove or slot [0341] 607 end face portion [0342] 701 recesses in the groove 606 [0343] 801 first ply of the jacket element 101 [0344] 802 ply of the first end element 103 [0345] 803 further ply of the jacket element 101 [0346] 804 thickness of the first ply 801 of the jacket element 101 [0347] 805 height of the first end element 103 in the longitudinal direction 106 [0348] 806 overhang length [0349] 1100 sheet-like composite [0350] 1101 outer surface [0351] 1102 inner surface [0352] 1103 polymer outer layer [0353] 1104 carrier layer [0354] 1105 polymer intermediate layer [0355] 1106 adhesive layer [0356] 1107 barrier layer [0357] 1108 polymer inner layer [0358] 1200 precursor [0359] 1300 method according to the invention for producing a liquid-tight container [0360] 1301 method step a) [0361] 1302 method step b)
