WO2005028324A1

WO2005028324A1 - Reclosable pack and production method thereof

Info

Publication number: WO2005028324A1
Application number: PCT/BE2004/000127
Authority: WO
Inventors: Eddy Daelmans; Jan Geudens
Original assignee: Amcor Flexibles Europe A/S
Priority date: 2003-09-19
Filing date: 2004-09-06
Publication date: 2005-03-31
Also published as: EP1516824A1

Abstract

The present invention relates to a reclosable pack (1) comprising on the outside of the full cut-off length of said pack at least one detachable strip (4), parallel to the longitudinal seal (3), intended to reclose the pack once said strip has been detached, said strip being only sealed in two cross seal areas (2) and/or on at least one point of the longitudinal seal area (3).

Description

RECLOSABLE PACK AND PRODUCTION METHOD THEREOF

Field of the invention [0001] The present invention relates to a reclosable pack, in general to a reclosable pack for snack food and confectionery food, and in particular for crisps, as well as to a method for its production.

Background of the invention and state of the art [0002] Many food-packs are generally made of metallized or transparent, PvDC-coated or AlOx-coated plastic films in order to provide a gas barrier, in particular a humidity barrier. In the case of large and medium-size food-packs, only part of their content is generally used immediately upon initial opening. Therefore, a reclosable pack, in particular for crisps, is a good option for keeping those crisps fresh and crispy. [0003] General ideas to reclose a bag have been disclosed in the literature. Well-known examples for those skilled in the art are plastic zippers or pressure- sensitive tape at the top open neck of a bag. Such pressure-sensitive closing systems are immediately contaminated by powder or fat contained in food such as crisps.

[0004] Most of these known solutions are not advantageous from the cost point of view, in particular for cheap disposable food packaging such as confectionery or crisp packs, where important technological adaptations of the process equipment are not economically justified. [0005] Herrington in US patent 4,913,560 discloses an adhesive-coated plastic tape welded on the outside of a plastic bag and protected by a brittle coating material. When manually stretched, the tape causes the brittle coating to crack and separate, exposing the adhesive. The tape is then wrapped around the neck of the bag to close it. [0006] Burke in patent application WO 00/73162 Al discloses a reclosable bag comprising towards its closed ends a fixed elastic single strip with an extensibility that is sufficient to enable it to be stretched and to make a turn around the longest dimension of the bag when filled. The elastic single strip is a rubber material with reversible elastomeric behaviour and low plasticity fixed outside the bag. Such elastic single strips cannot be introduced in usual VFFS/HFFS processes, requiring single strips with low elongation properties. [0007] Sampaio Camacho Jose Manuel discloses in his patent application F 2 810 966 a reclosable packaging comprising on the outside of the full cut-off length a detachable double strip (two layers) building a closed loop intended to reclose the packaging. The only single strip (one layer) disclosed in one embodiment of this document is not detached and is also not parallel to the longitudinal seal of the packaging. This single strip also builds a closed loop intended to be pulled over the pack opening.

Description of the figures

[0008] To make the understanding of the present invention easier, the appended figures show several views of bags and their reclosing methods . When considering these figures in connection with the following description, the invention and many of its advantages will be readily understood and appreciated. Figures 1 and 2 represent the first embodiment of the present invention, Figures 3, the second embodiment, Figure 4, the third embodiment, Figures 5, the fourth embodiment and figure 6 and 7, two different closing options of the fifth embodiment. [0009] Fig. la shows the front side of a VFFS/HFFS pack. [0010] Fig. lb shows the backside of a VFFS/HFFS pack with two single strips fixed or sealed at its ends at the outside of the pack in the cross seal areas. [0011] Fig.lc shows the standard opening of a crisp pack by cohesive rupture of the coextrusion layers. [0012] Fig. Id shows a pack where one of the two single strips sealed in the cross seal area is detached by breaking the seal at the bottom area of the pack. [0013] Fig.2a shows a pack where the other one of the two single strips sealed in the cross seal area is detached by breaking the seal at the bottom area of the pack. [0014] Fig.2b shows the backside of a pack with both crossed single strips to create closure loops for the pack. [0015] Fig.2c and 2d show the reclosing of the pack. [0016] Fig.3a shows two single strips sealed in the cross seal areas and in the upper zone (not covered by an anti-seal lacquer) of the longitudinal seal area of the backside of the pack. [0017] Fig.3b shows a pack where two single strips sealed in the longitudinal seal area on the backside are detached by breaking the seal in the bottom area of the pack. [0018] Fig.3c, 3d and 3e show the reclosing of the pack by making a knot with the single strips at the front side.

[0019] Fig.4a and 4b show a pack where one single strip, only sealed in the bottom and top cross seal area, is detached by breaking the seal in the bottom area of the pack. [0020] Fig.4c and 4d show the closing possibility with a single single strip in the lap seal area. [0021] Fig.5a shows a pack where two single strips sealed in the cross seal area are detached by breaking the seal at the bottom area of the pack for the first single strip and in the top area of the pack for the second single strip. [0022] Fig.5b shows the closing possibility by rolling the pack and diagonally overlapping both single strips . [0023] Fig.6a, 6b and 6c and Fig.7a, 7b, 7c and 7d show two different reclosing methods of a pack where one single strip sealed in the two cross seal areas and only on an anchoring point in the longitudinal seal area on the backside are detached by breaking the seal in the bottom and in the top area of the pack. Two anti-seal lacquer zones are present in this embodiment. In this case, the two cross seal areas fall together with the top and bottom of the longitudinal seal (fin or lap seal) .

Aims of the invention [0024] The aim of the present invention is to disclose a reclosable pack, in particular for snacks, obtainable by a vertical and/or horizontal form fill and seal process (VFFS/HFFS) without major adaptation of the pack machinery and without a major cost increase of the final pack.

Summary of the invention

[0025] The present invention discloses a reclosable pack comprising on the outside of the full cutoff length of said pack at least one detachable single strip, parallel to the longitudinal seal, sealed at least on the cross seal areas of the pack and intended to build an open loop able to reclose said pack, once said single strip has been detached on at least one sealing point. [0026] In a first aspect of the present invention, the reclosable pack comprises at least one anti- seal lacquer zone on the pack and/or on the detachable strip to avoid the sealing of said strip on said anti-seal lacquer zone . [0027] In a second aspect of the present invention, the reclosable pack further comprises at least one anchoring seal point positioned on the longitudinal seal of the pack between two anti-seal lacquer zones. [0028] Furthermore, the present invention discloses a method for the production of a reclosable pack, characterised in that said detachable single strip is heat- sealed or glued on the outside of said pack during a vertical and/or horizontal form fill and seal process. [0029] The method of the present invention further discloses that said detachable single strip is glued instead of heat-sealed during a vertical and/or horizontal form fill and seal process. [0030] Finally the present invention discloses the use of the reclosable pack of the invention for snack- food packaging, confectionery packaging and crisp packaging.

Detailed description of the invention [0031] The reclosable packaging of the present invention can be produced on common horizontal and/or vertical form fill and seal processing machines (VFFS/HFFS) by adding to the normal packaging material at least one single strip of low extensibility running in the packaging line on the outside of the packaging material. Non- restrictive examples of packaging materials and single strips are films of polyolefins, polyesters, polyamides, PVC, polystyrene, their copolymers, blends or laminates in mono or multilayer combinations with heat-seal coatings, barrier coatings, paper or metallic layers. The expression "single strip" should be understood as an indivisible mono or multilayer film unable to build a closed loop. In the particular case of crisp packs, extrusion or solvent adhesive based laminates of inside printed outer transparent BOPP (bioriented polypropylene) , laminated against a metallized BOPP are privileged. Particularly envisaged combinations for snack food packs are BOPP/PE; BOPP/CPP; BOPP/blownPP; PET/PP; PET/CPP; OPA/PE; paper/PE. [0032] The single strips are generally partially or completely sealed or glued on the outside of both ends of the pack in the cross directional seal area and/or along the longitudinal seal (lap or fin seal) with the rest of the packaging material on the backside of the VFFS/HFFS pack. The zones where the single strips should not adhere are covered by an anti-seal lacquer. The longitudinal seal is resealed in the cross seal area representing the connection of the longitudinal seal and the cross seal. [0033] Preferred material combinations for the single strips are BOPP/PET; BOPP/PE; PET/PE; OPET or OPA with peelable/rupture hot seal coating, OPET/extrusion coated PE and PET with seal coating.

[0034] The chosen pack/single strip seal combinations should of cause be appropriate and are well known by those skilled in the art. Examples are respectively BOPP/BOPP; BOPP/HS coating; PET/peel coating; PET/PE peel; PET/CPP peel, etc.

[0035] Possible seals for this kind of packaging are also well-known by those skilled in the art. Non- restrictive examples are cold and heat-seal coatings such as hot melts, PVDC coatings, acrylic coatings, latex-based cold sealing coatings, etc. [0036] The consumer of snack packs does not always pay attention to the opening side of the pack. For that reason, the single strips disclosed in the present invention are disposed in such a way that opening at the "top" or at the "bottom" of the pack is possible without loosing the possibility of reclosing. For that reason, in the present invention, all different reclosing methods of a snack pack, result in a symmetrical disposal of the single strips and the different sealing points versus the "top" or the "bottom" of the pack. [0037] In a first embodiment of the present invention, two small single strips 4 are added on the outside of the packaging 1 over the complete cut-off length parallel to the machine direction. In this particular case, both single strips 4 are only sealed in the cross seal areas 2 and relatively distant from the longitudinal seal area 3, as illustrated in Fig. la and lb respectively showing the front side and the backside of a pack 1 with two single strips 4 fixed at its ends on the outside of the pack 1 in the cross seal areas 2. After the standard opening of the pack 1 by cohesive rupture, adhesive rupture or even peel of the coextrusion layers, two single strips 4 are detached by breaking the seal in the bottom area of the pack while keeping them sealed and attached in the top area of the bag. In the following step, both single strips are crossed (Fig. 2b) to create the possibility with two loops

(Fig. 2d) to reclose the pack 1. [0038] In a second embodiment of the present invention (Fig.3a to 3e) , two single strips 4 are sealed in the cross seal area 2 and in the longitudinal seal area 3 of the backside of the pack 1. In this embodiment, two single strips 4 are sealed together with the longitudinal seal 3 until the middle of the pack. An anti-seal lacquer is applied between the single strips 4 and the packaging 1, defining an anti-seal lacquer zone 5 to make said single strip 4 detachable until the middle of the pack. Fig. 3b shows two single strips 4 being detached by breaking the seal at the bottom area of the pack 1 followed by making a knot with the single strips on the front side (Fig. 3d and 3e) to reclose the pack. [0039] In a third embodiment of the present invention, only one single strip 4 is sealed in both cross seal areas and nowhere else. Said single strip 4 is detached by breaking the seal in the bottom area of the pack 1 (Fig. 4b) and reclosed by turning said single strip

4 around the top of the pack 1. [0040] A fourth embodiment of the present invention is represented in Fig. 5a and 5b. In this embodiment, a first single strip 4 is detached in the bottom cross seal area and remains attached in the top seal area, a second single strip 4 is detached in the top cross seal area and remains attached in the bottom seal area. The two detached single strips represent two times the full length of the cut-off length and provide different possibilities for reclosing the bag and from which, one is represented in Fig. 5b. [0041] A fifth embodiment of the present invention is disclosed in the figures 6a, 6b and 6c and 7a, 7b, 7c and 7d. In this embodiment, a single single strip 4 is sealed along the longitudinal seal on three different points. Two sealing points are on the contact point of both cross seal areas and longitudinal seal, the third one in the middle of the pack 1 on the longitudinal seal 3. This point is called the anchoring point 6. Between the three sealing points and the pack 1, two anti-seal lacquer zones

5 are used to avoid the sealing in between said sealing points . Two different reclosing possibilities provided by this embodiment are represented in the figures 6c, 7b and 7c.

[0042] Other possibilities of reclosing the pack 1 resulting from the disclosed embodiments are of cause possible. Non restrictive examples are reclosing without detaching the single strip and using said single strip as a loop for the pack, etc.

[0043] An advantage of the present invention is the possibility to add one or two single strips in the

VFFS/HFFS packaging line without any extra adaptation of the process and with basically only the single strip material as additional cost.

[0044] An further advantage of the present invention is that the standard opening, by cohesive rupture, adhesive rupture or peel of the coextrusion layers in the cross seal area of the pack, remains the same and does not change the habits of the consumer.

[0045] Legend 1. Pack

2. Cross seal

3. Longitudinal seal (lap or fin seal) . Detachable single strip (one layer)

5. Anti-seal lacquer zones 6. Anchoring seal point

Claims

CLAIMS 1. Reclosable pack (1) comprising on the outside of the full cut-off length of said pack (1) at least one detachable single strip (4) , parallel to the longitudinal seal (3) , sealed at least on the cross seal areas (2) of the pack (1) and intended to build an open loop able to reclose said pack (1) , once said strip (4) has been detached on at least one sealing point. 2. Reclosable pack (1) according to claim 1, characterised in that said reclosable pack (1) comprises at least one anti-seal lacquer zone (5) on the pack (1) and/or on the detachable strip (4) to avoid the sealing of said strip on said anti-seal lacquer zone (5) . 3. Reclosable pack (1) according to Claim 1, further comprising at least one anchoring seal point (6). positioned on the longitudinal seal (3) of the pack (1) between two anti-seal lacquer zones (5) . 4. Method for the production of a reclosable pack (1) according to claim 1, characterised in that said detachable strip (4) is heat-sealed or glued on the outside of said pack (1) , during a vertical and/or horizontal form fill and seal process. 5. Method for the production of a reclosable pack (1) according to Claim 5, characterised in that said detachable strip (4) is glued instead of heat- sealed during a vertical and/or horizontal form fill and seal process. 6. Use of the pack according to Claim 1 for snack-food packaging. 7. Use of the pack according to Claim 1 for crisp and confectionery packaging.