Re-closable, tamper-resistant, stand-up package

Description

FIELD OF THE INVENTION

The present invention relates to flexible packaging. More specifically, it relates to stand-up type pouches that have tamper-evident, re-closable openings.

BACKGROUND OF THE INVENTION

Currently, most stand-up, re-closable packages are made in such a way that the consumer must tear away and discard the tear strip at the top of the package to access the product within the package. The tear strip is typically located above the zipper or slider at the top of the package. Because of the way these packages are made, the bag material often tears unreliably and not along a straight line. Sometimes the bag material only partially tears, which leaves leftover edges of film that interfere with the reclosing function of the zipper or slider. Many consumers also do not enjoy holding and then disposing the torn-away part of the package.

Furthermore, the construction of these stand-up, re-closable packages requires a heavier, thicker film material that adds to their production cost. While these stand-up packages have the advantage of being tamper evident because access can only be made after part of the bag has been permanently destroyed, the noted disadvantages are problems that the packaging industry still faces. Therefore, it would be desirable to provide a re-closable, tamper-evident, stand-up package that avoids the aforementioned problems in the prior art, is less expensive and easier to manufacture, and functions reliably.

SUMMARY OF THE INVENTION

The package of the present invention meets the need in the packaging arts for a better re-closable, stand-up package. The package of the present invention is tamper-evident but does not have the usual tear-off strip. The novel package has stand-up functionality and has an economical and reliable tamper-evident and re-closable opening system that has many consumer applications.

In one preferred embodiment of the invention, the package originates from two feed rolls. One roll is a flexible film web and the other is an adhesive tape. A reclosing layer is constructed from a strip of web material taken from a side of the film feed roll and a length of the tape. The tape and the strip are then adhesively joined so that they partially overlap laterally. A lateral slit is made in the web and the closure layer is then affixed to the web with a portion of the tape overlapping the slit. The body of the package is then formed by the simultaneous heat sealing of the package and reclosing layer along the side edges of the package body. After contents are added to the package, it is closed by heat sealing the top edges of the package body with the top of the closure layer strip.

More specifically, the package has a body formed by folding a flexible film web at a bottom to create opposing front and back panels. The panels are united along opposing lateral side edges thereof and along top edges of the panels at the top end of the body. So constructed, the body defines an interior space for holding contents dispensable through an opening provided by a lateral slit through the front panel.

A two-part composite closure layer consists of a strip of web material and an adhesively-coated tape that is partly adhered to the strip in a laterally overlapping manner. As a result of this construction, a top portion of the strip is not covered by the tape and a bottom portion of the tape is not covered by the strip. The closure layer lies laterally across the front of the front panel with the tape on the outside of the layer. The top portion of the strip not covered by the tape is united to the front and rear panels along the top of the body and along the side edges of the body by heat sealing. The closure layer strip extends from the top edge of the body downward to a point above the front panel slit. A die cut pull tab on the closure layer strip provides a dry edge for grasping and tearing open the strip. A tear line is defined by perforations that extend downwardly from either side of the pull tab. The top edge of the tape lies between the pull tab and the bottom edge of the strip. A bottom portion of the tape not covered by the strip extends downward over the package opening slit and is secured to the front panel by adhesion and at the sides by heat sealing. The heat sealing of the closure later is preferably accomplished at the same time as the formation of the package body.

The closure layer strip is preferably non-adhesive and is composed of the package flexible film taken from a side edge of the film during the package production process. The fold at the bottom of the package body is preferably a gusset fold that permits the package to stand upright on its own. That is to say that the package can be free-standing upright lengthwise on its vertical axis.

The package of the present invention has many differences from prior art stand-up packages that incorporate a zipper or a slider with a tear-off strip. Other advantages and differences will follow from the foregoing explanation and the following drawings and description of the invention. The preferred embodiment of the invention will provide one of skill in the art with a full understanding of what has been invented. It will thereby be appreciated that the stand-up package has various advantages over the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top right front perspective of a package in accordance with an embodiment of the invention;

FIG. 2 is a partial bottom left perspective of the package of FIG. 1;

FIG. 3 is a top right front perspective of the package of FIG. 1 shown in an opened configuration;

FIG. 4 is a cross-section taken along lines 4-4 of FIG. 1; and,

FIG. 5 is a cross-section taken along lines 5-5 of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT

A re-closable, stand-up package in accordance with a preferred embodiment of the invention is shown in FIGS. 1-5. The package has a body with a top 11, a bottom 13 and vertically-extending opposed side edges 15, 17. The package has front and rear panels 16, 18 formed by folding a web of flexible film at the bottom of the package into a gusset fold 19 best seen in FIG. 2. The panels are joined by heat sealing along the side edges 15, 17 and then along the top edge 12, which creates a package body with an enclosed interior space 8 for holding the contents of the package. The front panel 16 has a lateral slit 14 that provides an opening through which the package contents can be dispensed.

Referring to FIGS. 1 and 4, the lateral slit 14 is closed/sealed with a two-part closure layer comprising a non-adhesive strip of web film 23 a transparent tape 21 having an adhesive coating 31. The tape 21 and the strip 23 overlap along a laterally-extending connection interface 31a wherein the tape 21 is arranged on the outside of the strip 23 at the connection interface 31a. The tape 21 and strip 23 are of equal length and extend the full width of the package. With reference to the orientation shown in the drawings, the connection interface 31a is formed between the upper portion of the tape and the lower portion of the strip 23. The connection interface 31a is formed by an adhesive, preferably a permanent adhesive, on the top portion 21a of the tape 21, and heat seals 20 at the edges.

Along its length (width of the package), the top portion 23a of the strip 23 is adhered to the front panel 16 by a heat seal 29 and to the back panel 18 by a heat seal 20. Neither heat seal 29, 30 extends down to the tab 10 so that 10 the tab can be freely peeled away from the strip 23 as seen in FIG. 1. No other portion of the strip 23 is adhered to the front 16 or back 18 panel, including the portion of the strip at the connection interface 31a. Along the length of the tape (width of the package) and below the connection interface 31a, the tape 21 is 31b and a permanent adhesion interface 31c. The re-sealable adhesion interface 31b extends the length of the tape 21 (width of the package) and overlaps above and below the slit 14. The re-sealable adhesion interface 31b is provided so that the package can be re-sealed after emptying only a portion of its contents. The permanent adhesion interface 31c is provided so that the package contents cannot be tampered with without rupturing the closure layer.

The closure layer includes a pull tab 10 for opening the package. The pull tab 10 is formed by die cutting perforations 9 in the strip 23, and defines a top opening through which the package contents are dispensed. In FIGS. 1 and 4, tab 10 is shown partially pulled away from the strip 23; however, in this configuration, the re-sealable adhesive interface 31b of the tape 21 still covers the entire slit 14 and holds it closed.

The package is opened by first pulling the tab 10 away from the package so that the lower portion of the front panel separates from the upper portion of the front panel along the slit 14 as seen in FIG. 3. In this Figure, the closure layer is shown torn open along opposed tear lines 27. In this configuration, the re-sealable adhesive interface 31b of the tape 21 has been pulled away and no longer straddles the slit 14, which allows the front panel portions to separate along the slit 14. However, the tape 21 remains adhered to the front panel 16 at the permanent adhesive interface 31c. To empty the package, its contents must first pass through the slit 14 opening and then must pass behind the tape 21 and out through the torn opening at the top.

In a preferred embodiment, the slit 14 is a cut through the front panel 16 without the removal of material. When closed, the edges 25 and 26 of the slit 14 are in arranged in close abutment. While a slit is the preferred form of creating the primary package opening, other larger openings of different shapes and sizes other than a slit are possible. Some advantages of employing a slit are a greater surface area for the closure tape and a barrier preventing the tape 21 from adhering to the rear panel or package contents through the opening.

FIGS. 1 and 4 show the closure layer when the tab 10 is first torn open. The tape 21 is coated with a re-sealable adhesive 31 across the top in the middle area below the tear line. In all other areas especially all areas below the slit, the tape adhesive is a permanent adhesive to prevent tampering. The tape is preferably transparent so that package graphics beneath the tape are not hidden. After contents are first placed into the package, the front and rear panels 16 and 18 together with strip 23 are all heat sealed simultaneously across the top of the package by melted material 30 between the panels and melted material 29 between the front panel and the strip 23. The joinder of the front and rear panels at the sides and across the top creates an interior space 8 for holding contents of the package

Referring now to FIG. 5, the package is depicted fully opened as also shown in FIG. 3. By pulling the tab 10, the closure strip 23 has been opened along opposed tear lines 27. The tape 21 spans the gap between the top edge of the lower portion of the front panel 16 and the bottom portion of the strip 23. With the slit 14 now pulled open, an opening 7 is formed which permits the contents of the package occupying the interior space 8 to be dispensed behind the tape 21 and then through the second opening at the top defined by the tear line 27. The other numbered elements of FIG. 5 correspond to those mentioned in regard to FIG. 4 without further description needed.

With continued reference to FIGS. 4 and 5, to open the package the user grasps the closure layer strip 23 in the area of the pull tab 10 and tears it from the top portion of the closure strip 23 along the perforated tear line 27 as seen in FIG. 4. The pull tab 10 provides a dry edge for grasping and easily tears open the closure layer because it is not adhered to the package body in the area of the tear lines but only at the side edges and along the top of the package body by heat seal attachment 29. It remains attached to the package body unlike the tear-off strips of the prior art. Further pulling on the tab separates the tape portion of the closure layer from above the slit opening so that contents of the package can then be removed through the slit by separating the slit sides to form an opening 7 as seen in FIG. 5. As the contents are dispensed, they pass behind the tape 21 and through the closure layer opening defined by the tear line 27 in the closure layer strip 23. The package can be resealed simply by pressing the tape back against the front panel over the slit. After a first opening, the torn closure layer provides permanent evidence that the package has been opened or tampered with.

The embodiment depicted in FIGS. 1-5 can be manufactured by production machinery which need only be fed by a single roll of flexible film web material and a roll of adhesive tape. In production, the web travels along a path during which a strip of material is cut from a side edge of the film web. Thereafter, perforations are die-cut into the strip along a desired tear line. This perforated strip is then adhesively united with the adhesive tape forming the above described two-part closure layer. The web is then laterally slit and a cut segment of the closure layer is applied across the width of the web with a portion of the tape not covering the strip applied over the slit. The web is then folded with a gusset-forming fold device creating the opposing front and rear panels. The closure layer and side edges of the panels are then all united by heat sealing on the sides. After contents are added into the package, the top portion of the closure layer strip and the panels are heat sealed across the top, closing the package. One advantage of this package structure and manufacturing process is that there is no waste or remaining scrap left over to dispose.

From the foregoing it will be apparent to one of skill in the packaging arts that a stand-up pouch has been devised which is very economical to produce. It provides an easy-open, re-closable, tamper-evident construction in a stand-up package that does not require a tear-off component. Because the contents of the package can only be dispensed through the closure layer, the tearing open of the closure is a permanent indication of a first opening of the package or tampering. Compared to competing packages which employ a zipper or a slider opening the present invention can be formed from much thinner material saving cost. These advantages and others represent a significant advance in the packaging arts.

While only one embodiment of the invention is depicted in the drawings described above, there can be variations in dimension and proportionality. Furthermore, the means of production can be any suitable means available to the art at that time. Many modifications to the preferred embodiment may be possible without departing from the scope and spirit of the invention which shall be defined only by the following claims and their legal equivalents.