Easy opening reclose systems for cigarette packaging
10081484 ยท 2018-09-25
Assignee
Inventors
Cpc classification
B65D75/5833
PERFORMING OPERATIONS; TRANSPORTING
B65D85/1045
PERFORMING OPERATIONS; TRANSPORTING
B65D85/1018
PERFORMING OPERATIONS; TRANSPORTING
B65D65/14
PERFORMING OPERATIONS; TRANSPORTING
International classification
A24F15/00
HUMAN NECESSITIES
B65D65/14
PERFORMING OPERATIONS; TRANSPORTING
Abstract
The present invention is related to a reclosable pack (1) of smoking articles (2), said pack comprising a sealed enclosure having a front wall, a back wall, two side walls (7), a top-end wall (8) and a bottom-end wall (6), said enclosure comprising a flexible packaging laminate around a bundle of smoking articles (2), the laminate having a built-in easy-opening access comprising a permanently tacky adhesive (3) sandwiched between two film structures, said structures comprising an outer score line (13) formed through the thickness of the outer layer structure (12) and an inner score line (14) formed through the thickness of the inner layer structure (9), both delimiting separable opening portions, in which a region of the outer opening portion between the outer (13) and inner (14) score lines is attached to an underlying surface of the inner structure via a permanently tacky adhesive (3), the outer opening portion being peelable from the underlying surface of the inner layer structure (9) to build an opening flap (4), and the outer opening portion being re-attachable to the underlying surface of the inner structure (9) via said permanently tacky adhesive for reclosing, in use, the opening access, wherein the permanently tacky adhesive (3), in use, remains located after being peeled on the underlying surface of the inner structure (9) and wherein the permanently tacky adhesive layer (3) is patterned and located on the surface delimited by the outer score line (13) and the inner score line (14).
Claims
1. A reclosable pack of smoking articles, said pack comprising a sealed enclosure having a front wall, a back wall, two side walls, a top-end wall and a bottom-end wall, said enclosure comprising a flexible packaging laminate around a bundle of smoking articles, the laminate comprising inner and outer film structures laminated to one another face-to-face via a layer of a permanent adhesive extending over the entire surface of the laminate, the laminate having a built-in easy-opening access comprising a permanently tacky adhesive sandwiched between the inner and outer film structures, said structures comprising an outer score line formed through the thickness of the outer film structure and an inner score line formed through the thickness of the inner film structure, both delimiting separable opening portions, in which a region of an outer opening portion between the outer and inner score lines is attached to an underlying surface of the inner film structure via the permanently tacky adhesive, the outer opening portion being peelable from the underlying surface of the inner film structure to build an opening flap, and the outer opening portion being re-attachable to the underlying surface of the inner film structure via said permanently tacky adhesive for reclosing, in use, the built-in easy-opening access, wherein the permanently tacky adhesive, in use, remains located after being peeled on the underlying surface of the inner film structure and wherein the permanently tacky adhesive is patterned and located on the underlying surface delimited by the outer score line and the inner score line.
2. The pack according to claim 1, wherein said opening access is exclusively located at the top-end wall of the sealed enclosure.
3. The pack according to claim 1, wherein said pack comprises a release layer between the permanently tacky adhesive and the permanent adhesive.
4. The pack according to claim 3, wherein the release layer extends over the entire surface of the laminate.
5. The pack according to claim 4, wherein the flexible packaging laminate further comprises an opaque layer located between the inner film structure and the outer film structure, the depth of the first and second scoring lines being limited by said opaque layer.
6. The pack according to claim 5, wherein the opaque layer is the release layer, the permanent adhesive layer, an aluminium layer or a printed layer.
7. The pack according to claim 1, wherein adhesion at 20? C. of the permanently tacky adhesive with the sealed enclosure is comprised between 1 and 10 N/15 mm according to test method FINAT No 2.
8. The pack according to claim 1, wherein adhesion at 20? C. of the permanently tacky adhesive with the inner film structure is at least 2N/15 mm stronger than adhesion of the permanently tacky adhesive with the outer film structure.
9. The pack according to claim 1, wherein the sealed enclosure is an inner liner of a carton box.
10. The pack according to claim 1, wherein adhesion at 20? C. between the permanently tacky adhesive and the sealed enclosure is comprised between 1 and 5N/15 mm according to test method FINAT No 2.
11. The pack according to claim 1, wherein adhesion at 20? C. between the permanently tacky adhesive and the sealed enclosure is comprised between 2 and 3 N/15 mm according to test method FINAT No 2.
12. A method for the production of the reclosable pack according to claim 1, comprising the steps of: applying a predetermined pattern of the permanently tacky adhesive onto the underlying surface of the inner film structure comprising at least one layer of flexible material; covering at least said predetermined pattern with a protective over-lacquer layer or release layer, thereby obtaining the inner film structure; applying the layer of the permanent adhesive across an entire surface of the first film structure to cover both the over-lacquer layer and the possible uncovered surface of said first film structure; adhesively joining face-to-face the first film structure to the second film structure via the permanent adhesive so as to form the laminate; forming the built-in easy-opening access configured to be reclosed in the flexible packaging laminate, by scoring the inner and the outer offset score lines in the inner and outer film structures, respectively to form an integrated flap that can be lifted out of the plane of the laminate to form the easy-opening access; forming the reclosable pack around the bundle of smoking articles.
13. The method according to claim 12, wherein the over-lacquer layer covers the entire surface of the structure to cover both the permanently tacky adhesive and the inner film structure.
14. The method according to claim 13, wherein the over-lacquer layer or release layer is applied in a liquid state, so that the difference of level induced by the permanently tacky adhesive that is patterned is smoothed out by the over-lacquer layer or release layer.
15. The method according to claim 14, wherein the over lacquer is applied by solvent coating.
16. The method according to claim 12, wherein the first and the second offset score lines are performed by laser scoring.
17. The method according to claim 16, wherein the depth of the laser scoring is limited by an opaque layer located between the first and the second film structures.
Description
SHORT DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
(5)
(6)
(7)
LIST OF REFERENCE SYMBOLS
(8) 1. Reclosable pack 2. Smoking article 3. Permanently tacky adhesive layer 4. Enclosure flap 5. Carton box 6. Bottom wall 7. Side wall 8. Top wall 9. Inner structure or first structure 10. Over-lacquer or release layer 11. Permanent laminating adhesive 12. Outer structure or second structure 13. Outer score line or second score line 14. Inner score line or first score line
DETAILED DESCRIPTION OF THE INVENTION
(9) The present invention is related to a reclosable pack 1 of smoking articles 2, the pack comprising a sealed enclosure comprising a flexible packaging laminate around a bundle of smoking articles 2, the laminate having a built-in easy-opening access. The built-in easy-opening access has in practice the form of an aperture and an enclosure flap 4, the opening comprising on its edges a permanently tacky adhesive (PTA) layer 3, also called pressure-sensitive adhesive. As a general embodiment, the opening access can extend over the top-end wall 8 and the front wall of the reclosable pack 1 (
(10) In a particular embodiment, the opening access is exclusively located on the top wall of the reclosable pack 1 as represented in the
(11) The flexible packaging laminate used for the reclosable pack 1 of the present invention comprises a first (inner) 9 and second (outer) film structure 12 laminated to one another. On the laminate used in the present invention, we define a first film structure 9 and a second film structure 12. On the reclosable pack, these structures can be called the inner structure 9 and the outer structure 12. Each of the first and second film structures (9, 12) can be a single layer (such as a single polymeric sheet material) or can include two or more layers laminated to one another or even a coextruded multilayer structure. The first and second film structures (9, 12) can further include printed indicia as appropriate for a particular downstream packaging application.
(12) The permanently tacky adhesive (PTA) is preferably pattern-applied (for example in the shape of a U) to a surface of one of the first or second film structures (9, 12). The PTA pattern is then preferably covered with an over-lacquer layer 10. The over-lacquer layer adheres to both the PTA layer 3 and the uncovered surface, and works as a protective or release layer so that the structure with the PTA can be stored on a roll without any blocking effect. Examples of the over-lacquer layer 10 include nitrocellulose materials, nitrocellulose materials mixed with an anti-blocking agent such as silica, and water-based acrylic resins.
(13) The over-lacquer layer 10 can be applied only on the PSA/PTA layer or can advantageously be applied across the entire surface of the structure. In this latter case, the over-lacquer layer 10 preferably has a variable thickness, smoothing out the thickness variability induced by the patterned PTA. For example, the over lacquer 10 is applied in a liquid state by using an appropriate solvent, such as water in the case of water-based acrylic resins.
(14) A layer of permanent adhesive 11 is then applied across the entire surface of the film structure (also referred to as continuous or full coverage) to cover the PTA, over-lacquer layer (if any) and the possibly uncovered first or second structure. Alternatively, a layer of the permanent adhesive 11 can be applied across the entire surface of any of both structures.
(15) By permanent adhesive 11 is meant adhesive that is usually used in lamination process for obtaining permanent adhesion as opposed to peelable adhesive.
(16) The first and second structures (9, 12) are directed into an opposing face-to-face relationship so that the pattern-applied PTA 3, over-lacquer layer 10, and full-coverage permanent adhesive layer 11 are sandwiched between the first and second structures (9, 12). The permanent adhesive 11 adheres to the over-lacquer layer 10 and joins the first and second structures (9, 12) to one another in order to form the flexible packaging laminate.
(17) When the PTA 3 is covered by the over-lacquer layer 10, the first structure 9 with the pattern-applied PTA 3 and over-lacquer layer 10 can be rolled and stored on a roll without blocking effect, and subsequently laminated to a second structure 12 with the permanent adhesive 11 in a separate processing step. Alternatively, the first and second structures (9, 12) with the pattern-applied PTA layer 3, over-lacquer layer 10 and full-coverage permanent adhesive layer 11 can be laminated to one another in an integrated (in-line) process.
(18) To form the built-in open and reclose structure in the flexible packaging laminate according to the invention, a first and a second offset score lines are formed in the first and second structures, respectively to form an integrated flap that can be lifted out of the plane of the laminate to form an opening. The opening allows access to a product enclosed by a package formed of the flexible packaging laminate.
(19) In particular, a first (inner) score line 14 is formed in one of the first or second structures that will form the inner surface of the resulting package (referred to herein as the inner structure). The first score line 14 defines an inner opening surface corresponding to the inner surface of the flap 4 and forms the opening in the laminate when the flap 4 is detached therefrom. The first score line is generally delineated along the inner periphery of the PTA pattern.
(20) A second outer score line 13 offset from the first score line is formed in the other of the first or second structures (9, 12) that will form the outer surface of the resulting package (referred to herein as the outer structure). The second score line defines an outer closing surface corresponding to the outer surface of the flap 4 once it is detached from the laminate. The second score line is generally delineated along the outer periphery of the PTA pattern.
(21) The location of the second score line 13 is selected so that the outer closing surface of the flap 4 includes an edge region extending beyond the outer edge of the underlying inner opening surface of the flap 4. The pattern-applied PTA is accordingly located in the edge region between the first and second score lines (14, 13). The permanent adhesive 11 joins the first and second structures (9, 12) except in this edge region between the first and second score lines (14, 13).
(22) When the flap 4 is lifted out of the plane of the laminate, the inner structure 9 is separated at the first score line 14 and the outer structure 12 is separated at the second score line 13. The permanent adhesive 11 permanently joins the inner opening surface of the inner structure 9 to the outer closing surface of the outer structure 12, lifting the flap 4 forms the opening in the laminate. The flap 4 can be closed by returning it to its original position. The edge region of the outer closing surface of the flap 4 is reattached to an underlying portion of the inner structure 9 via the PTA 3 located in this edge region. The PTA remains on the underlying portion.
(23) The offset score lines (13, 14) are advantageously performed by laser scoring, the depth of the scoring being preferably limited by an opaque layer. The opaque layer can be diffusive of reflective, such as a layer comprising whitening filler such as TiO.sub.2 or metallic layer such as an aluminum layer.
(24) Typical film structure to be used in the invention are, from outer to inner layers: Outer lacquer/printing layer/OPP 30 ?m/permanently tacky adhesive (PTA) 3 ?m/permanent adhesive 3 ?m/metalized OPP 45 ?m Outer lacquer/printing layer/OPP 30 ?m/permanently tacky adhesive (PTA) 3 ?m/release lacquer/permanent adhesive 3 ?m/metalized OPP 45 ?m Outer lacquer/printing layer/PET 18 ?m/permanently tacky adhesive (PTA) 3 ?m/permanent adhesive 3 ?m/metalized PET 18 ?m