Abstract
The present invention refers to a sheetlike composite (100), comprising as a layer sequence in a direction from an outer surface (101) of the sheetlike composite (100) to an inner surface (102) of the sheetlike composite (100) a) an outer polymer layer (103), b) a colour application (104), c) a carrier layer (105), and d) a barrier layer (107);
wherein the outer polymer layer (103) is characterised by a density in a range from 919 to 925 kg/m.sup.3. The invention further refers to a container precursor (500) and to a container (700), in each case comprising at least part of the preceding sheetlike composite (100); to processes (300, 400, 600) for preparing a sheetlike composite (100), a container precursor (500), and a closed container (700); to the preceding products; and to uses of the sheetlike composite (100), and of a polyolefin.
Claims
1. A sheetlike composite, comprising as a layer sequence in a direction from an outer surface of the sheetlike composite to an inner surface of the sheetlike composite a) an outer polymer layer, b) a colour application, c) a carrier layer, and d) a barrier layer; wherein the outer polymer layer is characterised by a density in a range from 919 to 925 kg/m.sup.3.
2. The sheetlike composite according to claim 1, wherein the outer polymer layer is further characterised by a melt flow index in the range from 2 to 6 g/10 min.
3. The sheetlike composite according to claim 1, wherein the colour application adjoins the carrier layer.
4. The sheetlike composite according to claim 1, wherein the outer polymer layer is an outermost layer of the sheetlike composite.
5. The sheetlike composite according to claim 1, wherein the outer polymer layer is further characterised by a melting temperature in the range from 107.5 to 115° C.
6. A process, comprising as process steps a) provision of a sheetlike composite precursor, comprising a carrier layer; b) superimposing a colour application to the carrier layer on a first side of the carrier layer; c) superimposing an outer polymer composition to the colour application on the first side of the carrier layer and obtaining an outer polymer layer from the outer polymer composition; wherein the process comprises a further process step of superimposing a barrier layer to the carrier layer on a further side of the carrier layer which is opposite to the first side; wherein the outer polymer composition is characterised by a density in a range from 920 to 926 kg/m.sup.3.
7. A sheetlike composite, obtainable by the process according to claim 6.
8. A container precursor, comprising at least one sheetlike region of the sheetlike composite according to claim 1.
9. A container, comprising at least one sheetlike region of the sheetlike composite according to claim 1.
10. A process, comprising as process steps: a. providing at least one sheetlike region of the sheetlike composite according to claim 1, this at least one sheetlike region including a first longitudinal rim and a further longitudinal rim; b. folding the at least one sheetlike region; and c. contacting and joining the first longitudinal rim to the further longitudinal rim, thereby obtaining a longitudinal seam.
11. A container precursor, obtainable by the process according to claim 10.
12. A process, comprising as process steps a] providing the container precursor according to claim 8; b] forming a base region of a container by folding the sheetlike region; c] closing the base region by joining faces of the sheetlike region to each other; d] filling the container precursor with a foodstuff; e] forming a top region of the container by folding the sheetlike region; and f] closing the top region by joining faces of the sheetlike region to each other, thereby obtaining a closed container.
13. A closed container, obtainable by the process according to claim 12.
14. A use of the sheetlike composite according to claim 1 for preparing a foodstuff container.
15. A use of a polyolefin having a density in a range from 920 to 926 kg/m.sup.3 in an outer polymer layer of a sheetlike composite, comprising as a layer sequence in a direction from an outer surface of the sheetlike composite to an inner surface of the sheetlike composite a) the outer polymer layer, b) a colour application, c) a carrier layer, and d) a barrier layer.
Description
[0281] In the drawings:
[0282] FIG. 1 is a diagrammatic cross section through a sheetlike composite of the invention;
[0283] FIG. 2 is a diagrammatic top view of the sheetlike composite of FIG. 1;
[0284] FIG. 3 is a flow chart of a process of the invention for preparing a sheetlike composite;
[0285] FIG. 4 is a flow chart of a process of the invention for preparing a container precursor;
[0286] FIG. 5 is a diagrammatic view of a container precursor of the invention;
[0287] FIG. 6 is a flow chart of a process of the invention for preparing a closed container;
[0288] FIG. 7 is a diagrammatic view of a closed container of the invention;
[0289] FIGS. 8 and 9 show photographs of the top regions of multiple containers according to the comparative example 59; and
[0290] FIG. 10 a photograph of a closed container prepared for the above described OTR or WVTR measurement.
[0291] FIG. 1 shows a diagrammatic cross section through a sheetlike composite 100 of the invention. The sheetlike composite 100 comprises as a layer sequence in a direction from an outer surface 101 of the sheetlike composite 100 to an inner surface 102 of the sheetlike composite 100: an outer polymer layer 103, a colour application 104, a carrier layer 105, an intermediate polymer layer 106, a barrier layer 107, an adhesion promoter layer 108 and an inner polymer layer 109. The sheetlike composite 100 of FIG. 1 is configured in accordance with example 13 presented above. Accordingly, the outer polymer layer 103 has a density of 924 kg/m.sup.3.
[0292] FIG. 2 shows a diagrammatic top view of the sheetlike composite 100 of FIG. 1. The sheetlike composite 100 comprises four longitudinal grooves 202 which each are oriented in a first direction 205 which is a longitudinal direction. In the first direction 205, the sheetlike composite 100 has a first bending resistance of 65 mN. A further direction 206 is perpendicular to the first direction 205. In the further direction 206 the sheetlike composite 100 has a further bending resistance of 160 mN The sheetlike composite further comprises longitudinal rims 203 and transversal rims 204. The longitudinal grooves 202 connect the two transversal rims 204 with each other. The carrier layer 105 comprises a plurality of fibres 201. Therein, a fibre run of the carrier layer 105 is oriented in the further direction 206. Hence, the carrier layer 105 has a transverse fibre. The sheetlike composite 100 is a pre-cut or blank for the production of a single closed container 700 as shown in FIG. 7.
[0293] FIG. 3 shows a flow chart of a process 300 of the invention for preparing a sheetlike composite 100. The process 300 comprises a process step a) 301 of providing a sheetlike composite precursor which consists of a carrier layer 105 having a hole 505. In a process step b) 302, a colour application 104 in form of a 4-colour-decoration is printed onto a first side of the carrier layer 105. Subsequently, in a process step c) 303, an outer polymer composition having a density of 924 kg/m.sup.3 is coated onto the colour application 104 via a laminar extrusion coating method, thereby obtaining an outer polymer layer 103 from the outer polymer composition. In a process step d) 304, an intermediate polymer layer 106, a barrier layer 107, an adhesion promoter layer 108 and an inner polymer layer 109 are coated onto the carrier layer 104 on a further side of the carrier layer 104 which is opposite to the first side. Subsequently, the obtained laminate is provided with grooves and cut to size in order to obtain the sheetlike composite 100 of FIG. 1.
[0294] FIG. 4 shows a flow chart of a process 400 of the invention for preparing a container precursor 500. In a process step a. 501, the sheetlike composite 100 of FIG. 1 is provided, for example by the process 300 of FIG. 3. As shown in FIG. 2, this sheetlike composite 100 includes a first longitudinal rim 203 and a further longitudinal rim 203. In a process step b. 402, the sheetlike composite 100 is folded along the longitudinal grooves 202. In a process step c. 403, the first longitudinal rim 203 and the further longitudinal rim 203 are pressed onto each other and heat sealed to one another, thereby obtaining a longitudinal seam 502. The container precursor 500 of FIG. 5 is obtained.
[0295] FIG. 5 shows a diagrammatic view of a container precursor 500 of the invention. The container precursor 500 shown here is a sleeve which is suitable for the production of a single closed container 700, in particular of the closed container 700 shown in FIG. 7. Further, the sleeve includes a top region 503 and a bottom region 504. The top region 503 and the bottom region 504 respectively include further grooves 506 which are not longitudinal grooves 202. The top region 503 and the bottom region 504 can respectively be closed by folding along the further grooves 506 and sealing. The closed container 700 as shown in FIG. 7 can thus be obtained from the sleeve. Accordingly, the container precursor 500 is a precursor produced in the process for producing the closed container 700. In the container precursor 500 the sheetlike composite 100 has been folded along the longitudinal grooves 202, thereby obtaining four longitudinal folds 501. The sleeve moreover includes a longitudinal seam 502 along which the longitudinal rims 203 of the sheetlike composite 100 have been sealed to one another. The longitudinal folds 501 as well as the longitudinal seam 502 are each oriented in the first direction 205, hence perpendicular to the further direction 206 which is the direction of the transverse fibre of the carrier layer 105. The container precursor 500 further comprises a hole 505 in the carrier layer 105. This hole 505 is covered by the outer polymer layer 103 (not shown here), the intermediate polymer layer 106 (not shown here), the barrier layer 107, the adhesion promoter layer 108 (not shown here) and the inner polymer layer 109 (not shown here) as hole-covering layers. As can be seen in FIG. 5, the outer surface 101 is facing outward, hence to the environment of the container precursor 500.
[0296] FIG. 6 shows a flow chart of a process 600 of the invention for preparing a closed container 700. In a process step a] 601, the container precursor 500 of FIG. 5 is provided. In a further process step b] 602, the sheetlike composite 100 is folded in the base region 504, thereby forming a base region of a container. The latter base region is closed via heat sealing with hot gas in a process step c] 603. The obtained cup-like container is sterilised and then filled with a foodstuff 702 in a process step d] 604. In a subsequent process step e] 605, the sheetlike composite 100 is folded further in the top region 503, thereby forming a top region of the container. This latter top region is closed by ultrasound sealing regions of the inner surface 102 of the sheetlike composite 100 to each other. Therein, regions of the outer surface 101 of the sheetlike composite 100 are contacted with a sonotrode and an anvil of an ultrasound sealing system, respectively. Then fold flaps 704 which have been obtained by forming the top region of the container are heat sealed to the container body 705, thereby obtaining the closed container 700 of FIG. 7.
[0297] FIG. 7 shows a diagrammatic view of a closed container 700 of the invention. The closed container 700 can be obtained by the process of FIG. 6. Accordingly, the closed container 700 includes the sheetlike composite 100 of FIG. 1. The closed container 700 further includes 12 edges, 4 of which are longitudinal edges 701. The closed container 700 surrounds an interior which includes a foodstuff 702. The foodstuff 702 can be liquid, but can also include solid constituents. The closed container 700 shown in FIG. 7 is of one-piece design. In its top region 503, a top seal 706 has been obtained by ultrasound sealing. Therein, the inner polymer layer 109 has been used as sealant. The closed container 700 can moreover be provided with a fitment to improve ease of opening. Here, the hole 505 in the carrier layer 105 of the sheetlike composite 100 is covered by a cap 703 with an opening aid which is attached to the closed container 700. The closed container 700 is of the so called brick-type which has a cuboid shape. Fold flaps 704 have been joined to the container body 705 by heat sealing using the outer polymer layer 103 as sealant.
[0298] FIGS. 8 and 9 each show a photograph of multiple containers according to the comparative example 56. Both of these figures show views on the top regions 503 of the containers. Accordingly, the holes 505 in the carrier layer 105 can be seen. Further, the containers have substandard top seals 801. Along these top seals, the laminates suffered from delamination. The top seals 801 of FIG. 8 even show cardboard fibre tears of the carrier layer 105.
[0299] FIG. 10 shows a photograph of a closed container prepared for the above described OTR or WVTR measurement. The plate 1001 having the gas inlet 1003 and the gas outlet 1004 can be seen. The plate 1001 is glued to the container in a gas tight manner via the sealing compound 1002. For measuring the OTR or WVTR of the container, the respective measurement device is to be connected to the gas inlet 1003 and the gas outlet 1004.
LIST OF REFERENCE NUMERALS
[0300] 100 sheetlike composite of the invention
[0301] 101 outer surface
[0302] 102 inner surface
[0303] 103 outer polymer layer
[0304] 104 colour application
[0305] 105 carrier layer
[0306] 106 intermediate polymer layer
[0307] 107 barrier layer
[0308] 108 adhesion promoter layer
[0309] 109 inner polymer layer
[0310] 201 plurality of fibres
[0311] 202 longitudinal groove
[0312] 203 longitudinal rim
[0313] 204 transversal rim
[0314] 205 first direction
[0315] 206 further direction
[0316] 300 process of the invention for preparing a sheetlike composite
[0317] 301 process step a)
[0318] 302 process step b)
[0319] 303 process step c)
[0320] 304 process step d)
[0321] 400 process of the invention for preparing a container precursor
[0322] 401 process step a.
[0323] 402 process step b.
[0324] 403 process step c.
[0325] 500 container precursor of the invention
[0326] 501 longitudinal fold
[0327] 502 longitudinal seam
[0328] 503 top region
[0329] 504 bottom region
[0330] 505 hole
[0331] 506 further groove
[0332] 600 process of the invention for preparing a closed container
[0333] 601 process step a]
[0334] 602 process step b]
[0335] 603 process step c]
[0336] 604 process step d]
[0337] 605 process step e]
[0338] 606 process step f]
[0339] 700 closed container of the invention
[0340] 701 longitudinal edge
[0341] 702 foodstuff
[0342] 703 cap with opening aid
[0343] 704 fold flap/“ear”
[0344] 705 container body
[0345] 706 top seal
[0346] 801 substandard top seal
[0347] 1001 plate
[0348] 1002 sealing compound
[0349] 1003 gas inlet
[0350] 1004 gas outlet
