Reclosable packages and methods for their manufacture are described herein and, in particular, packages having adhesive-based reclosure features.
Reclosable packages are used for a variety of food products (e.g., chewing gum sticks, chocolates, candy, and the like). Since consumers may not consume the food products in the packages in one serving, the packages can include reclosable features, such as mechanical fasteners or adhesive strips, to allow for reclosure of the packages.
Manufacture of reclosable packages having mechanical fasteners, such as interlocking fastener strips, can require additional manufacturing steps, which can undesirably add complexity and cost to the manufacturing process. Moreover, the cost of the mechanical fasters can undesirably increase the cost of the package.
Adhesive-based reclosable fasteners provide one alternative to the mechanical fasteners. For example, a reclosable flap may include an adhesive strip and may fold to cover a top opening of the package and attach to a wall of the package, which has a matching adhesive strip in alignment with the adhesive strip on the flap. Such arrangements where both the flap and the package wall include an adhesive strip can undesirably add cost and complexity to the manufacturing process. In addition, such reclosable packages can be manufactured such that the package material and the flap are formed from a single web of material and a multitude of fold lines and/or laser score lines are used to permit the flap to move from a closed position to an open position and vice versa. The incorporation of such fold lines and laser score lines can undesirably increase the complexity and cost of manufacturing of such packages, depending upon the configuration of the packages.
The flexible packages described herein can be advantageously manufactured without requiring the use of laser scoring or multiple fold lines. The packages are formed from two materials, such as films. A first material is folded to form the front and back panels of the flexible package and to define what will be a mouth or opening of the package. A second material having one or more strips of applied adhesive is attached to the first material such that the opening is covered. The second material can have a strip of relatively permanent adhesive for attachment to the back panel and a strip of reclosable adhesive for repeated attachment to the front panel to reclose the package after opening. The flexible packages described herein can be more cost-effective to manufacture than laser-scored packages because they can be manufactured without the use of laser machinery and do not require additional processing to create multiple fold lines.
In one form, a reclosable package comprises a flexible material forming opposed front and back panels connected via a bottom seal and a pair of end seals intersecting the bottom seal to bound at least a portion of a package interior. The front and back panels each have a top end and a maximum height defined by a distance from the top end to the bottom seal. The maximum height of the back panel is greater than the maximum height of the front panel such that there is an exposed segment of the back panel not covered by the front panel. The package further comprises a closure flap including a first adhesive layer and a second adhesive layer. The closure flap is non-removably attached to the exposed segment of the back panel via the first adhesive layer. The closure flap is removably attached to the front panel via the second adhesive layer.
Use of the terms “non-removably” and “removably” are relative, and apply to normal use. For example, it may be possible to separate the closure flap from the exposed segment of the back panel upon application of significant force, but can require more force, and in some circumstances several times the amount of force, to separate as compared to separating the closure flap from the front panel. During normal use, it is preferred that the closure flap will not separate from the exposed segment of the rear panel. Normal use can include an opening frequency corresponding to the number of items in the package, or a multiple thereof.
The closure flap can be movable from a closed position, where the second adhesive layer attaches the flap to the front panel, and an open position, where the flap is sufficiently unattached to the front panel such that access is provided to the package interior.
The first and second adhesive layers each can comprise an adhesive strip on an interior surface of the closure flap. The second adhesive layer can be a pressure sensitive material adapted to permit the closure flap to open to provide access to the package interior, and to reclose the package to restrict access to the package interior. The closure flap may further comprise a first non-adhesive area between the first and second adhesive layers, such that the first and second layers are spaced. The closure flap can include a top edge and a bottom edge and further comprises a second non-adhesive area between the second adhesive layer and the bottom edge of the closure flap. The second non-adhesive area can facilitate grasping of the flap by a user to move the closure flap from the first position to the second position.
The closure flap can optionally include a third adhesive layer, disposed on an opposite side of the second adhesive layer as compared to the first adhesive layer, adapted to seal a portion of the closure flap to the front panel of the package. The closure flap can include at least one line of weakness configured to permit the closure flap to divide into a remainder portion adhered to the front panel using the third adhesive layer and a moveable portion selectively attachable to the front panel using the second adhesive layer, with the first adhesively layer non-removably attaching the moveable portion to the exposed segment of the rear panel.
The reclosable package described herein can be in combination with a food product in the interior of the package.
Methods of forming the above-described packages include: directing a first web of material in a machine direction; placing at least one food product onto the first web of material; folding opposing longitudinal edges of the first web of material inward over adjacent portions of the first web of material and around the food product and bringing the opposing longitudinal edges of the first web of material toward each other to a position where folded inward opposing longitudinal edges of the first web of material are offset from a central longitudinal axis of the first web of material such that a gap is formed between the folded inward opposing longitudinal edges of the first web of material; applying a second web of material including at least the first and second adhesive layers to the first web of material such that the first adhesive layer non-removably attaches to the first web of material in the gap between the folded inward opposing longitudinal edges and the second adhesive layer removably attaches to a folded over portion of the first web of material proximate the folded inward opposing longitudinal edges of the first web of material; forming the pair of end seals; and separating the package from a remainder of the first web of material and the second web of material.
The separating of the package can include cutting through the first web of material and the second web of material along the central longitudinal axis of the first web of material. The separating of the package may further include cutting through at least one of the end seals.
An exemplary reclosable flexible package as described herein includes front and back panels formed from a folded flexible substrate, such as film or paper, with an attached, unfolded closure flap formed from a pressure sensitive tape or a heat sealable film or other substrate and including a strip of pressure sensitive adhesive (“PSA”) or the like disposed thereon. The closure flap can be removably attached to one of the panels via the PSA strip to both seal the package and provide an open/reclose feature for the package such that the package can be easily opened and reclosed while maintaining package integrity. The closure flap can be non-removably attached to a second panel via a relatively permanent adhesive to permit the closure flap to move between the open and closed positions without being detached from the second panel. The closure flap can include a non-adhesive area below the PSA strip to facilitate easy opening of the package and easy reclose/reseal of the package when needed.
With reference to
The front and back panels 104 and 106 of the package 100 are formed from a continuous film substrate (e.g., substrate 202 of
The front and back panels 104 and 106 are attached at their peripheral side edge portions 112 and 114 via two side seals 116 and 118, respectively. The side seals 116 and 118 can be formed via laminating, heat sealing, or attaching via an adhesive the side edge portions 112 and 114 of the front and back panels 104 and 106 to each other to form the interior 113 of the package 100.
In the form depicted in
A first adhesive layer 122 is disposed on the interior surface 121 of the closure flap 108 proximate the top end 125 of the closure flap 108 for creating a permanent attachment between the closure flap 108 and the interior surface 109 of the back panel 106 of the package 100, as shown in
The first adhesive layer 122 extends continuously from one side edge 123 of the closure flap 108 to the other side edge 125 of the closure flap 108, as shown in
The interior surface 121 of the closure flap 108 includes a second adhesive layer 124 disposed thereon proximate the bottom end 129 of the closure flap 108 for creating a non-permanent or removable attachment between the closure flap 108 and the exterior surface 107 of the front panel 104, as can be seen in
The second adhesive layer 124 extends continuously from one side edge 123 of the closure flap 108 to the other side edge 125 of the closure flap 108, as depicted in
The second adhesive layer 124 may be in the form of a strip including a PSA that permits the opening of the closure flap 108 to provide access to the package interior 113 and reclosing of the closure flap 108 to restrict access to the package interior 113, and optionally, to hermetically seal the package 100. The PSA of the second adhesive layer 124 can be a UV-cured PSA. Instead of a PSA strip, the second adhesive layer 124 may include any other type of material that provides for the removable attachment of the closure flap 108 to a portion of the front panel 104 (and optionally, the back panel 106) of the package 100. The materials comprising the second adhesive layer 124 are preferably chosen such that the second adhesive layer 124 can remain attached to the closure flap 108 and the exterior surface 107 of the front panel 104 of the package 100, even after multiple openings and reclosures of the package 100. The second adhesive layer 124 is preferably selected from materials that are neutral or non-reactive to the product (e.g., food) contained in the package interior 113. In one approach, the second adhesive layer 124 is configured to provide a reclosable seal even in abnormally cold and/or abnormally hot conditions. For example, the second adhesive layer 124 can include one or more materials effective to maintain the closure flap 108 attached and the package 100 in a closed condition and/or sealed in a temperature range of about −10° C. to about 90° C.
The closure flap 108 includes a first adhesive-free or non-adhesive area 126 positioned at least in part between a bottom edge of the first adhesive layer 122 and a top edge of the second adhesive layer 124, as depicted in
The closure flap 108 further includes a second adhesive-free or non-adhesive area 128. In the illustrated form, the second non-adhesive area 128 is positioned at least in part between a bottom edge of the second adhesive layer 124 and the bottom edge 129 of the closure flap 108. In one approach, the second non-adhesive area 128 forms a pull tab that permits a user to move the closure flap 108 in upward and/or downward directions for opening and reclosing the package 100.
The closure flap 108 is movable from a first (closed or sealed condition) position where the first adhesive layer 122 is attached to a portion of the back panel 106 and the second adhesive layer 124 is attached to a portion of the front panel 104, toward a second (open condition) position where the first adhesive layer 122 remains attached to the portion of the back panel 106, but the second adhesive layer 124 is spaced away from the portion of the front panel 104 to provide the user access to the package interior 113 through the access opening 130. When moving between the first and second positions, the closure flap 108 can pivot about an area when the first adhesive layer 122 is attached to the back panel 106.
To open the package 100, a user can grasp the closure flap 108 (e.g., at the second non-adhesive area 128) and pull the closure flap 108 in an upward direction to expose an access opening 130, as shown in
It is to be appreciated that the relative dimensions of the first adhesive layer 122, second adhesive layer 124, and first and second non-adhesive areas 126 and 128 have been shown for illustration purposes only, and may be varied to accommodate various package sizes. Further, it is to be appreciated that while the closure flap 108 has been shown with two adhesive layers 122 and 124 and two non-adhesive areas 126 and 128, it is to be appreciated that the closure flap 108 can be formed with three, four, or more adhesive layers, with three, four, or more non-adhesive areas, or without one or both of the adhesive-free areas 126 and 128.
In one form, there may be no gap between the first and second adhesive layers 122 and 124, and the second adhesive layer 124 may continuously extend to the bottom edge 129 of the closure flap 108. In another form, the dimensions of the first adhesive layer 122 may remain unchanged and the second adhesive layer may be dimensioned such that it is approximately equal to the combined dimension of the second adhesive layer 124 and the non-adhesive areas 126 and 128 illustrated in
While
Methods of manufacturing the package 100 can use heat seals, cold seals, extrusion and adhesive lamination, or co-extrusion. Generally, when food products such as gum sticks are enveloped and sealed within a first film substrate that will form the front and back panels 104 and 106 of the package 100, a second layer of film substrate that will form the closure flap 108 is attached to the first film substrate, and the first and second film substrates are then cut into individual packages 100. One exemplary method of manufacturing the package 100 is generally shown in
A film substrate 202 is unwound from a feed roll 200 and is directed in a machine direction, as shown in
The folded inward edges 208 and 210 are offset from the central longitudinal axis such that a gap 212 is formed between the folded inward edges 208 and 210, as depicted in
A second feed roll 300 including a second film substrate 302 is positioned above (or in any other suitable orientation) over portions of the first film substrate 202 having folded inward edges 208 and 210, and the second film substrate 302 is applied onto the first film substrate 202.
The second film substrate 302 includes a first adhesive layer 322, a pair of first non-adhesive areas 326 adjoining the first adhesive layer 322 on each side, a pair of second adhesive layers 324 adjoining the first non-adhesive areas 326, and a pair of second non-adhesive areas 328 adjoining the second adhesive layers 324, as seen in
As the longitudinal edges 204 and 206 of the first film substrate 202 are folded inward toward each other to form the folded inward edges 208 and 210 such that portions of the film substrate 202 generally assume a double J-shape, the second film substrate 302 is applied on top of the film substrate 202 such that the first adhesive layer 322 is attached to the film substrate 202 in the gap 212, and the second adhesive layers 324 are attached over a respective one of the folded inward edges 208 and 210. The portions of the second film substrate 302, when attached to the respective portions of the first film substrate 202 (which will form front and back panels 104 and 106 of the package 100), form the closure flap 108 of the package 100.
After the attachment of the portion of the second film substrate 302 that will form the closure flap 108, the food products 400 and 402 become fully contained within the film substrates 202 and 302 and a pair of end seals (e.g., seals 116 and 118) can be formed using, for example, using one or more sealing jaws to seal the first film substrate 202 and the second film substrate 302. The end seals can be formed, for example, via heat sealing, lamination, or fusion of appropriate portions of the first and second film substrates 202 and 302.
Finally, the packages 100 are singulated from the remainder of the first and second film substrates 202 and 302. For example, cutting devices can make one or more cuts though the first film substrate 202 and the film substrate 302 to singulate the individual packages 100. The cuts can include a cut in the central longitudinal axis of the materials, extending in the machine direction, as well as transverse cuts relative to the machine direction. This method advantageously allows the package 100 to be formed without having to use laser scoring, multiple fold lines, or other potentially complex techniques.
Turning to further details of the second film substrate 302, and with reference to
Furthermore, it can be advantageous to have the surface of the second substrate 302 on an opposite side from the second adhesive layer 324 have a lesser affinity for adhesion as compared to the surface of the second substrate 302 to which the second adhesive layer 324 is attached. This is because when the substrate 302, with the second adhesive layer 324 thereon, is wound in the roll 300, it is desirable to have the second adhesive layer 324 remain on the surface to which it was originally applied as opposed to transferring to the opposite surface when unwound. Alternatively, a removable liner could be used to restrict the second adhesive layer 324 from transferring during unwinding. Depending upon the properties of the first adhesive layer 322, the same concerns can be addressed in the same manner for the first adhesive layer 322.
Although the second substrate 302 is described and illustrated in
The package 500 illustrated in
The closure flap 508 is similar to the closure flap 108 in that it includes first and second adhesive layers 522 and 524 and the first and second non-adhesive areas 526 and 528, which are identical to the first and second adhesive layers 122 and 124 and the first and second non-adhesive areas 126 and 128 of the closure flap 108, as shown in
The third adhesive layer is disposed proximate the bottom end 529 of the closure flap 508 for sealing the package 500 and creating a permanent or non-removable attachment between the closure flap 508 and the exterior surface 107 of the front panel 504, as illustrated in
The third adhesive layer 530 extends continuously from one side edge 523 of the closure flap 508 to the other side edge 525 of the closure flap 508, as depicted in
When the package 500 is in a sealed or closed condition, the third adhesive layer 530 is attached to the exterior surface 507 of the front panel 504 to seal (e.g., hermetically) the package 500, as shown in
After the separation of the closure flap 508 along the score line 534, a user can grasp the closure flap 508 (e.g., at the second non-adhesive area 528 or the second adhesive layer 524) and pull the closure flap 508 in an upward direction to expose an access opening, substantially as shown in
It is to be appreciated that the relative dimensions of the first, second, and third adhesive layers 522, 524, and 530 and the first, second, and third non-adhesive areas 526, 528, and 532 of the closure flap 508 have been shown in
While preferred embodiments have been described in detail, variations and modifications can be effected within the configurations described herein.