Abstract:
A flexible package has a dispensing opening with a closure label overlying the opening that is permanently attached to the package by heat sealing along an edge portion adjacent the dispensing opening. The label has a releasable adhesive on the underside of the remaining portion for selectively opening and resealing the dispensing opening. The package is formed from a film that is partially die cut to form the dispensing opening. The label with the releasable adhesive is then applied to the package over the dispensing opening and heat sealed along an edge portion of the film. The film and attached label are later folded to form an envelope, filled with dispensable product, and heat sealed to encapsulate the product. The label can be selectively opened and resealed to enable access to the product through the dispensing opening. Complete removal of the label is prevented by the heat-sealed edge portion.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. provisional application Serial No. 60/295,650, filed Jun. 4, 2001. 
     
    
     
       BACKGROUND OF INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    This invention relates to resealable packages. In one aspect, the invention relates to a package with a dispensing opening and a resealable cover which is permanently sealed in part to the package and has a releasable adhesive on an underside for selectively securing the resealable cover over the dispensing opening. In another of its aspects, the invention relates to a package with a dispensing opening and a resealable, tamper-evident cover. In yet another of its aspects, the invention relates to a laminate film web comprising a plurality of regularly-spaced, partially die-cut openings each having a permanently attached, resealable cover over the opening. In yet another of its aspects, the invention relates to a method for manufacturing a package from a laminate film web having a dispensing opening and a resealable cover  
           [0004]    2. Description of the Related Art  
           [0005]    Flexible tubular packages such as for disposable cleansing cloths have a resealable label for closing a dispensing opening in the package. The package is manufactured from an elongated thin film that is folded and sealed along its length, cut to lengths, filled and sealed along its edges to create the package. The label is affixed to the package over the dispensing opening and may include a generally transverse die-cut line that extends partially across the label and retards the removal of the label from the package when the label is peeled back from the opening. Notwithstanding the die cut, the label can be completely removed from the package. The label has a releasable adhesive on its underside for selectively opening and resealing the dispensing opening.  
           [0006]    The label may be more securely attached to the package along one portion of the label through the use of a more secure adhesive with a line separating the more secure adhesive from the releasable adhesive serving as a hinge. The releasable adhesive may comprise a more permanent adhesive with a releasable coating or a more permanent adhesive in a pattern that provides for release of the label. In either case, the use of multiple coatings necessitates at least a two-step adhesive application process unless the removable portion is screened. Even though the adhesive may be considered as “permanent,” it typically is removable if enough force is applied. If a releasable adhesive is utilized for the entire label, the user can unintentionally remove the entire label from the package.  
           [0007]    U.S. Pat. Nos. 4,889,234 to Sorenson et al. and 4,771,891 to Sorenson et al. disclose a product box with a U-shaped perforation forming a pouring flap and a label permanently adhered to the box and to the flap. A single “permanent” adhesive is applied to the label in differing patterns. The adhesive pattern determines whether the label is more permanently or removably attached to the box. A fine pattern of more permanent adhesive around the perimeter of the flap enables the flap to be selectively removed and resealed.  
           [0008]    U.S. Pat. Nos. 6,000,726 to Campbell and 5,284,363 to Gartner disclose labels that are attached to a substrate through the use of a “permanent” adhesive along one portion of the label and releasably attached to the substrate through the use of a releasable adhesive on the remainder of the label.  
           [0009]    U.S. Pat. No. 4,128,954 to White discloses a label which is attached to a container by a thermosensitive adhesive along one portion of the label and provided with a second adhesive for attaching a separable portion of the label to another surface.  
           [0010]    In packages where sterile contents are important, tamper-evident packages are important. In packages that have a resealable cover or label over a dispensing opening, it is desirable that a tamper-evident label indicate to the purchaser if the resealable cover has been peeled back and resealed.  
         SUMMARY OF INVENTION  
         [0011]    According to the invention, a flexible package has a dispensing opening with a closure label overlying the opening that is permanently attached to the package, preferably by heat sealing, along an edge portion adjacent the dispensing opening.  
           [0012]    The label is provided with a releasable adhesive on the underside of the remaining portion for selectively opening and resealing the dispensing opening.  
           [0013]    The package is formed from a film that is first at least partially die cut to weaken the film and eventually form the dispensing opening. The label with a releasable adhesive is then applied to the package over the dispensing opening and heat sealed along an edge portion to the film. The film and attached label are later folded to form an envelope, filled with product, and heat sealed to encapsulate the product. The label can be selectively opened and resealed to enable access to the product through the dispensing opening. Complete removal of the label is prevented by the heat-sealed edge.  
           [0014]    In one embodiment of the invention, the label further has a pull tab without adhesive at a peel end portion of the label distal from the heat sealed edge portion to facilitate peeling back the label from the film to expose the dispensing opening.  
           [0015]    Preferably, the pull tab has a perforation or other weakened portion that divides the pull tab into a pull portion adjacent the peel end portion of the label and a tamper-evident portion remote from the peel end portion of the label. The tamper-evident portion of the pull tab is more permanently attached to the film and separates from the pull portion when the peel end portion of the label is first peeled back from the film.  
           [0016]    In one embodiment, the package is made from a a continuous web with multiple at least partially die-cut openings and one of the labels is attached to the continuous web adjacent to each of the at least partially die-cut openings for alternatively covering and uncovering the at least partially die-cut openings.  
           [0017]    Further according to the invention, a method of making a package with a dispensing opening and a label for selectively covering and uncovering the dispensing opening, comprising the steps of:  
           [0018]    at least partially forming the dispensing opening in a thin film;  
           [0019]    applying a label with a releasable adhesive over the dispensing opening in the film;  
           [0020]    and heat sealing, or otherwise permanently affixing, the label along one edge to the film adjacent to the at least partially formed dispensing opening.  
           [0021]    The method further comprises the step of forming the thin film into a package. 
       
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0022]    In the drawings:  
         [0023]    [0023]FIG. 1 is a perspective view of a package with a releasable label according to the invention.  
         [0024]    [0024]FIG. 2 is a perspective view of a portion of a packaging film for manufacturing the package of FIG. 1 showing a die-cut opening and a releasable label to be applied thereto.  
         [0025]    [0025]FIG. 3 is a schematic representation of a package and label manufacturing process according to the invention.  
         [0026]    [0026]FIG. 4 is a perspective view of a package with a releasable label according to a second embodiment of the invention.  
         [0027]    [0027]FIG. 5 is a view of the embodiment shown in FIG. 4 with the releasable label partially peeled back. 
     
    
     DETAILED DESCRIPTION  
       [0028]    The invention described herein comprises a package formed in part from a film having an opening therethrough which is removably covered by a cover label which is permanently attached to the film adjacent to the opening along a first edge, preferably by heat sealing, to form a hinge at one end of the cover label. The cover label further has a releasable adhesive on an underside thereof for contacting the film and releasably securing the cover to the film over the opening. The cover label can be selectively peeled back from the opening and resealed over the opening to alternately cover and uncover the opening. In one embodiment, the film is formed into a tubular package that is heat sealed at the ends thereof. In another embodiment, the film comprises a web having a plurality of openings partially die cut therethrough and a cover label covers each opening. The cover labels can be applied prior to or after forming the film into the package.  
         [0029]    Referring now to FIGS. 1 and 4, an embodiment of the invention is shown comprising a tubular package  10  with an attached releasable label  12  adapted to cover an opening  14  in the package  10 . The package  10  is a conventional flexible tubular package well-known in the art for containing disposable cleansing cloths, tissues, and similar products. The products are removed through the opening  14  which is formed as hereinafter described.  
         [0030]    Referring to FIGS. 1, 2 and  4 , in the preferred embodiment, the package  10  comprises a laminated, liquid-impervious thin film  20 , having an upper ply  21  and a lower ply  23 . The film  20  can be a polyethylene-backed aluminum foil laminated to a layer comprising a heat-sealable material such as polytetrafluoroethylene. An example of a suitable film  20  is DuPont SURLYN. The film  20  is formed into a tubular envelope by heat sealing the longitudinal edges (not shown) of the film and heat sealing the end portions  22 ,  24 . The package  10  is formed by folding the film  20  along a longitudinal axis to bring adjacent side edge portions of the film  20  together and sealing the edges together to form a tubular body. The tubular film is cut to lengths and filled with product. Heat and pressure are then applied to the end portions  22 ,  24  to bond the two plies  21  and  23  together and thereby seal the package.  
         [0031]    The opening  14  is formed by perforating or partially die-cutting the desired opening shape in the film  20  along a punch line  48  to define a removable shield  46 . Preferably, the punch line  48  only partially penetrates the film  20  so that the shield  46  remains attached to the film  20  to be later removed as hereinafter described. The label  12  is attached to the film  20  over the opening  14  prior to assembly of the film  20  into the final package  10 .  
         [0032]    The cover label  12  comprises a flexible, liquid-impervious thin film suitable for heat sealing to the upper ply  21  of the film material  20  to cover the opening  14 . A SURLYN film can also be used for the cover label  12 . The label  12  has a pull tab  36  at a first end and a heat-sealing edge  38  at a second, opposed end. If SURLYN film is used for the upper ply  21 , it can be laminated with a layer of thermoplastic material so that the cover label  12  can be heat sealed to the upper ply  21  of the film  20  at least at the area at which the label  12  is heat sealed to the upper ply  21 . Thus, it may be necessary to provide the heat-sealing apparatus for the end portions  22 ,  24  with a release material so that the heat-sealing apparatus can be readily separated from the upper ply  21  after completion of the heat-sealing process applied to the end portions  22 ,  24 . Alternatively, other materials and/or processes can be utilized for permanently sealing the label  12  to the upper ply  21  in order to mitigate any problems associated with heat sealing the label  12  to the upper ply  21  and the end portions  22 ,  24  together.  
         [0033]    In a preferred embodiment, shown in FIG. 4, the label  12  is provided with a mechanical hinge  40  extending the full width of the label  12  along the heat-sealing edge  38 . In an alternative embodiment, shown in FIG. 1, the label  12  is die cut along cut lines  42 , defining a mechanical hinge  40  comprising tabs  50  and a hinge line  44  along the heat-sealing edge  38 . The label has a visible side  30  and an adhesive side  32 . The visible side  30  is adapted to be imprinted with graphical or textual information about the product. The adhesive side  32  includes a releasable adhesive  34  that enables the label  12  to be repeatedly peeled from the package  10  and reapplied thereto. The releasable adhesive  34  is applied generally to the adhesive side  32 . However, in the preferred embodiment, the releasable adhesive  34  is not applied to the pull tab  36 , thereby leaving the pull tab  36  free of the package  10  to be grasped by a user. Further, the releasable adhesive  34  is not applied to the heat-sealing edge  38 .  
         [0034]    The label  12  with applied adhesive  34  is permanently attached to the package  10  over the opening  14  by heat-sealing the label  10  to the package  20  along the heat-sealing edge  38  adjacent to the opening  14 . The first time the label  12  is removed to open the package  10 , the shield  46  will be separated from the upper ply  21  up to the heat-sealing edge  38 . It will be obvious to one skilled in the art that separation of the shield  46  from the film  20  will be accomplished only if the adhesion of the shield  46  to the label  12  is great enough to overcome the attachment of the shield  46  to the film  20 . The label  12  can be progressively removed from the package  10  up to the hinge line  44  and will separate along the cut lines  42 , leaving the tabs  50  attached to the package  10 . The heat-sealing edge  38  will prevent any further removal of the label  12 . The label  12  can be resealed over the opening  14 , and the shield  46  will prevent contact between the adhesive  34  and the product.  
         [0035]    The process and apparatus for manufacturing the package will now be described. Referring to FIG. 3, a web  60  of preprinted film is fed from a supply roll  62  through a registration station  66  which registers the location of a preprinted mark on the film relative to a die-cutting station  64  and a label application station  68  for accurate die cutting and placement of the label  12 . The web  60  then passes through the die-cutting station  64  where the punch line  48  for the shield  46  is formed. The web  60  next passes through the label application station  68  where the label  12  is applied to the web  60 . The label  12  can also be imprinted on the visible side  30  and provided with the releasable adhesive  34  on the adhesive side  32  at the label application station  68 . The web  60  with the attached label  12  then passes through a heat-sealing station  70  at which the label  12  is heat sealed to the film  20  along the heat-sealing edge  38 . The web  60  is then fed onto a take-up roll  72  for later separation and assembly into individual packages. Alternately, rather than forming packages from the web  60 , the web  60  can be separated into individual portions having a punch line  48  and an associated label  12  for later attachment to rigid containers, such as cardboard boxes for disposable tissues, in order to provide a resealable opening for access to the contents of the box.  
         [0036]    It will be understood by one skilled in the art that the described process is generally continuous, and that the die-cutting and label-attachment steps can be performed for a plurality of labels applied to a continuous web of film comprising a plurality of die-cut openings. The package manufacturing process can be integrated into a package-filling operation in which the packages are die cut, filled, and then heat sealed. The process can be intermittent or continuous, depending on the nature of the equipment used. For example, the process can be continuous when a rotary die is used and intermittent when a reciprocating die is used. Both types of die-cutting equipment are well known.  
         [0037]    Referring now to FIGS. 4 and 5, where like numerals are used to designate like parts, the pull tab  36  has a perforated line  54  which separates an end portion  52  from the remainder of the pull tab  36 . The end portion  52  of the pull tab  36  is heat sealed or otherwise permanently affixed to the film  20  so that the pull tab  36  must be separated from the end portion  52  at the perforated line  54  in order to peel back the releasable adhesive portion of the label  12  from the film  20 . Thus, the label  20  provides a tamper-evident closure through the tab  36  and the heat-sealed or otherwise permanently attached end portion  52 .  
         [0038]    The invention has been described with respect to heat sealing a portion  38  of the label  12  to the film  20  and heat sealing the end portion  52  of the pull tab  36  to the film. Whereas heat sealing of one or both of these areas of the label  12  is preferred, other forms of permanently securing the label  12  to the film  20  are possible within the scope of certain embodiments of the invention. For example, in lieu of heat sealing, other means of making the hinge  40  permanent, including microencapsulation of a catalyst to permanently affix the label  12  to the film  20  can be employed.  
         [0039]    The process illustrated in FIG. 3 can be incorporated into a production line wherein the packages are actually filled with product and sealed. Thus, the package-making process can incorporate the process illustrated in FIG. 3 and can further include the steps of filling the packages and forming the packages.  
         [0040]    While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit.