Filled And Sealed Easily Opened Bag And Method Of Making Same

Abstract

A filled and sealed bag made of paper or similar flexible sheet material, and particularly well adapted for containing a sterile article, includes a front panel defining one wall of a pocket for containing the article. This front panel contains a relatively long slit covered by a closure strip which may be peelably removed from the bag to expose the slit and to allow the article to be removed from the bag, the adhesive used to hold the closure strip to the front panel being spaced a considerable distance from the edges of the slit so as to avoid the possibility of contaminating the enclosed object. The bag is made and filled by a process which includes slitting a web of sheet material along its length, applying and securing a closure strip to the slit web to rejoin the severed portions of the web and then forming bags from the web by folding and sealing individual pieces of the web which individual pieces are cut from the web to separate the individual bags.

Description

BACKGROUND OF THE INVENTION

This invention relates to containers made of flexible sheet material such as paper, and deals more particularly with such containers which are prefilled, sealed and provided with a means enabling each container to be readily opened by hand. It additionally relates to methods for making such a container.

Containers of the type with which this invention is concerned are sometimes commonly referred to as bags, flexible packages, envelopes, or pouches, and for the purpose of this description are referred to herein as bags.

It is common in the packaging art to manufacture, fill and seal bags in one overall operation and to provide the bags so formed with a tear strip or similar means enabling them to be easily opened by hand to facilitate the removal of their contents. The general object of this invention is to provide an improved bag of this character which may be made by a simple web forming process and which additionally particularly lends itself to use with sterile articles such as surgical sponges and dressings. In keeping with this, a more specific object of the invention is to provide a bag which may be filled with an object and later sterilized in the bag after the bag is sealed, the bag thereafter maintaining the object in a sterile condition until opened and being capable of being opened and its contents removed with minimal likelihood of contamination.

SUMMARY OF THE INVENTION

The present invention resides in a bag made of flexible sheet material and including overlying front and rear rectangular panels joined at their edges to form an object receiving pocket. The front panel includes an elongated slit covered by a closure strip bonded thereto by an adhesive or other bonding means enabling the closure strip to be peeled from the front panel when desired to expose the slit and allow the contents of the pocket to be removed therefrom. The adhesive or other bonding agent is located a substantial distance from the edges of the slit so as to avoid the possibility of its contacting and contaminating the enclosed article. Also, the fact that the slit is preformed by a clean cut eliminates the need for tearing any fibers during the opening process and accordingly eliminates ragged edges and loose fibers that might contaminate the enclosed object as it is removed from the bag. The front panel may also include a second slit which with the first slit defines an intermediate strip which is secured to the closure strip and which is removed from the front panel with the closure strip when the closure strip is peeled therefrom to expose a wide open mouth through which the contents of the bag may be more easily removed.

The invention also resides in the method for making a bag such as aforementioned and which method includes the steps of providing a piece of sheet material, slitting it, rejoining the slit portions with a closure strip and then forming the rejoined portions into a bag in such a manner that the closure strip in the finished bag appears on the outside of the bag and may be readily grasped to peel it from the bag and to expose the slit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a blank of sheet material from which a bag embodying the present invention may be made.

FIG. 2 is a cross-sectional view taken on the line 2--2 of FIG. 1.

FIG. 3 is a perspective view of the blank of FIG. 1 as viewed from the side thereof opposite from the side facing the viewer in FIG. 1.

FIG. 4 is a view similar to FIG. 1 but showing the blank of FIG. 1 at a subsequent stage of its development into a finished bag.

FIG. 5 is a view similar to FIG. 4 but showing the blank of FIG. 3 in a subsequent stage of its development toward a finished bag.

FIG. 6 is a view similar to FIG. 4 but shows the bag in its finished state.

FIG. 7 is a perspective view, drawn on a scale slightly enlarged from that of FIGS. 1 to 6, showing the finished bag of FIG. 6 as viewed looking generally toward the front panel thereof and with the closure strip partially peeled from the front panel to partially expose the slit therein through which the contents of the bag may be removed.

FIG. 8 is a somewhat diagrammatic side view showing a device for performing the initial steps of the process used to make the bags of FIGS. 6 and 7.

FIG. 9 is a plan view of the apparatus of FIG. 8.

FIG. 10 is a plan view of a finished bag comprising an alternative embodiment of this invention, the closure strip of the bag being shown partially removed from the front panel and a portion of the closure strip being shown broken away to reveal other details of construction.

FIG. 11 is a side view showing somewhat diagrammatically a device for performing the initial steps of a process for making the bag of FIG. 10. FIG. 12 is a plan view of the apparatus of FIG. 11.

FIG. 13 is a plan view of a blank of sheet material from which a bag comprising another embodiment of the present invention may be made.

FIG. 14 is a plan view of a blank of sheet material from which a bag comprising still another embodiment of the present invention may be made.

FIG. 15 is a perspective view showing a finished bag made from a blank such as that shown in FIG. 14.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning to the drawings, FIGS. 1, 2 and 3 show a blank of paper or similar sheet material from which one form of bag embodyinG this invention may be made. FIGS. 4 and 5 show the blank of FIG. 1 at intermediate stages in the development of the finished bag; FIG. 6 shows the finished bag as viewed from the rear panel thereof; and FIG. 7 shows the finished bag as viewed from the front panel thereof and in a partially opened condition. Considering first FIGS. 1, 2 and 3, the blank of sheet material is there indicated at 10 and comprises a generally rectangular piece of paper or other similar flexible sheet material commonly used for making bags. The six vertical lines 12, 14, 16, 18, 20 and 22 and the two horizontal lines 24 and 26 are fold lines about which the blank is subsequently folded to form the finished bag. The blank consists of a main piece of sheet material 11 and a second piece of sheet material referred to as a closure strip 30. The line 28 represents a slit extending the full length of the main piece 11 and dividing such piece into two separate parts. As seen in FIGS. 2 and 3, the two parts of the piece 11 are joined by the closure strip 30 which is bonded to the outer side or face of the piece 11.

The bonding of the closure strip 30 to the main piece 11 is of such a nature that the closure strip may subsequently be peeled from the main piece by manually pulling it therefrom. Preferably, this bonding is accomplished by means of a stripable adhesive material applied between the closure strip and the piece 11. As will be seen in FIGS. 2 and 3, the closure strip 30 extends the full length of the blank 10 and has a width approximately but not limited to being equal to the spacing between the fold lines 16 and 18. The zones at which the adhesive is applied is shown in FIG. 3 and includes two lengthwise extending lines 32 and 34 of adhesive and two transverse lines 36 and 38 of adhesive. As used herein, the term adhesive is intended to include such materials as synthetic or natural rubber latex which some times are more specifically referred to as cohesives, and one preferred form of adhesive for joining the closure strip to the blank is liquid latex which is initially applied to both the main piece 11 and to the closure strip 30 before the two are brought together, and which thereafter cohesively bonds the closure strip and the piece 11 to one another when the closure strip is brought into position adjacent the piece 11. In the case where a cohesive is used as the bonding agent, the closure strip prior to being joined with the piece 11 may on the side thereof eventually facing the piece 11 be entirely coated with the cohesive and the piece 11 may be coated with the same cohesive along the seal lines 32, 34,36, and 38. From FIG. 3, it should especially be noted that adjacent the lefthand end of the blank, as viewed therein, the transverse seal line 38 is spaced a slight distance from the free end edge of the blank so that adjacent such free edge the closure strip is unattached to the blank so as to enable it to be grasped by the user as hereinafter explained in more detail. This may or may not be the case with transverse seal 36, as desired.

Still referring to FIG. 1, the main panels of the finished bag are located between the two horizontal fold lines 24 and 26, and the portions of the blank located outboard of the fold lines 24 and 26 comprise end flaps used in sealing the ends of the bag. Considering the portions of the blank located between the horizontal fold lines 24 and 26, the portion located between the fold lines 16 and 18 in the finished bag comprises a front panel 40. The portion located between the fold lines 14 and 16 comprises a gusset panel 42, the portion located between the fold lines 12 and 14 comprises a gusset panel 44, the portion located between the fold line 18 and the fold line 20 comprises a gusset panel 46, and the portion located between the fold line 20 and the fold line 22 comprises a gusset portion 48. Outboard of the fold line 12 is a rear panel or edge portion 50a and outboard of the fold line 22 is the rear panel or edge portion 50b which panel portions 50a and 50b in the finished envelopes are adhesively sealed to one another and define a rear panel 50 shown in FIGS. 5 and 6. Outboard of the upper horizontal fold line 24 is an end flap 52 connected with the front panel 40, end flaps 54, 56, 58 and 60 connected with the gusset panels 42, 44, 46 and 48, respectively, and end flaps 60a and 60b connected with the rear panel portions 50a and 50b respectively and which in the finished envelope collectively define an end flap 60 for the rear panel, as shown in FIG. 5. Likewise, outboard of the lower horizontal fold line 26 the blank 10 includes an end flap 62 connected with the front panel 40, end flaps 64, 66, 68 and 69 respectively connected with the gusset panels 42, 44, 46 and 48, and the end flaps 70a and 70b connected with the rear panel portions 50a and 50b and which in the finished envelope together define an end flap 70 for the rear panel 50, as shown in FIG. 5.

In making a bag from the blank 10 of FIGS. 1, 2 and 3, the blank is first folded along the fold lines 12, 14, 16, 18, 20 and 22 as indicated in FIGS. 4 and 5, and the rear panel portions 50a and 50b are bonded to one another by a line of adhesive 72, shown in FIG. 4, to form the rear panel 50 and to form the blank into a generally tubular body. The gusset panels 42 and 44 and 46 and 48 connect the front panel 40 to the rear panel 50 along the two side edges of the front panel and allow for expansion of the bag to suit its contents. As shown in FIG. 5, the gusset panels 42 and 44 and 46 and 48 are sandwiched between the front and rear panels and extend inwardly from the side edges thereof when the bag is in its flattened condition as shown in FIG. 5.

Although not shown in FIGS. 1 to 5, the object to be contained in the finished bag may be placed on the blank 10 prior to the initiation of the folding steps so that as the rear panel portions 50a and 50b are folded over one another to form the rear panel 50 of the bag, they are also folded over the object to be contained in the bag thereby sandwiching the object between the front and rear panels and causing it to be sealed in the pocket of the bag after its ends are sealed as hereinafter described. As an alternative, the object to be contained in the bag may be placed in the bag after the blank is folded to the stage shown in FIG. 5, the article at this state being introduced into the bag by being slipped through one of its open ends, and if desired, the other end of the bag may be sealed prior to this introduction.

After the blank 10 is processed to the stage shown in FIG. 5, and the object to be contained therein introduced to its pocket, the ends of the bag are sealed. This is accomplished by folding the upper end flaps 52, 54, 56, 58, 59 and 60 about the upper fold line 24 and sealing them to the rear panel 50 by a line of adhesive 74. Similarly, the lower end flaps 62, 64, 66, 68, 69 and 70 are folded about the fold line 26 into overlying relationship with a part of the rear panel 50 and sealed to the rear panel 50 by a line of adhesive 76. It should particularly be noted that the shape of the blank 10 is such that the end flaps 52 and 62 connected to the main panel are longer than the end flaps 60 and 70 connected to the rear panel so that the lines of adhesive 74 and 76 not only hold the end flaps to the rear panel but effectively seal the openings at the ends of the bags to prevent the escape of the contents of the bag and also to prevent the ingress of bacteria or other contaminants.

It should also be noted that, as will perhaps best be understood from FIG. 6, the fact that the transverse line of adhesive 38 joining the closure strip 30 to the piece 11 terminates slightly short of the free end of the end flap 52 enables the adjacent end portion of the closure strip 30 to be grasped by hand to initiate its being peeled from the bag to open the bag, and preferably as indicated in FIG. 6, the portion of the closure strip which overlies the end panel 50 includes an appropriate legend 78 instructing the user to initiate opening at this point. It is obvious, of course, that the opening may also be initiated from the opposite closed end if the arrangement of the adhesive at such other closed end is such as described above. As shown in FIG. 7, stripping of the closure strip from the finished package exposes the slit 28 in the front panel 40 and allows the contents 80 of the package to be removed therefrom through the slit 28. Since the slit 28 is preformed in the package by a clean cut, no tearing occurs as the package is opened and accordingly no loose fibers or ragged edges are produced which are liable to cling to and contaminate the contents 80 as it is removed from the bag. Further, the adhesive located along the adhesive lines 32 and 34 is located a relatively great distance from the slit 28 so as not to be liable to contact and contaminate the objects 80 as it is removed from the bag or while it is in the bag.

Various methods may be used to form the bag shown in FIGS. 6 and 7, but preferably, the process employed includes initial steps whereby the blank 10 of FIG. 1, and a large number of identical blanks, is formed from a continuously or intermittently moving web of sheet material. FIGS. 8 and 9 by way of example show schematically a device for practicing such steps. Referring to these figures, the blank 10 is made from a main web 82 of sheet material supplied from a roll 84. From the roll 84, the web 82 is fed to an adhesive applying station 86 at which adhesive is applied to the web, as by a roll 88, to form an adhesive pattern defining the adhesive lines 32, 34, 36 and 38 of each blank. Following this, the web 82 passes to a slitting station 90 at which it is slit along its length, as by slitting roll 92 to form the slit 28 of each blank. Following the slitting station 90, the web passes to a marrying station 94 at which a narrower web 96 is married or bonded to the web 82 to form a closure strip 30 for each of the blanks subsequently cut from the web 82.

The narrow web 96 is supplied from a roll 98 and is bonded to the web 82 by passing with the web 82 between two rolls 100 and 102. If a cohesive material such as latex is used to bond the web 96 to the web 82, the adhesive applied to the web 82 at the adhesive station 86 is a cohesive such as latex and the web 96 also includes a quantity of such cohesive on the face thereof brought into contact with the web 82 so that the strip 96 is cohesively joined to the web 82 by such material, and preferably the entire extent of such face of web 96 is coated with the cohesive material. Following the marrying station 94, the web 82 is cut transversely to separate therefrom individual blanks such as the blank 10 of FIG. 1 and the blanks so formed are subsequently folded and sealed as required to form the finished package. The apparatus used for cutting and folding and sealing the blanks may take various different forms well known to persons skilled in the art and need not be described in detail.

FIG. 10 shows a bag comprising an alternative embodiment of this invention. In the bag of FIGS. 6 and 7, a single slit 28 is provided in the front panel 40 of the bag and after the closure strip 30 is peeled from the bag, the edges of the slit 28 must usually be spread to some extent to enable the removal of the bag contents. In contrast to this, the bag of FIG. 10 in its front panel 40 includes two slits 104 and 106 extending parallel to the side edges of the front panel. These slits 104 and 106 define between themselves an intermediate strip 108 which is bonded to the closure strip 30 so that when the closure strip is peeled from the bag the strip 108 remains with the closure strip and exposes a wide mouth 110 in the front panel through which the contents 80 of the bag may be removed. Adjacent the left-hand end of the bag, as viewed in FIG. 10, the front panel 40 also includes a transverse slit or weakened line 112 which defines one end of the intermediate strip 10, this end of the bag being that end from which peeling of the closure strip 30 from the bag is to be initiated. A similar transverse slit 113 may be made at the other end of the bag but is not always necessary.

Except for the bag of FIG. 10 including two slits 104 and 106 in place of the single slit 28 of the bag of FIGS. 6 and 7, the bag of FIG. 10 is or may be identical to the bag of FIGS. 6 and 7 and therefore need not be further described in detail.

Apparatus for carrying out the initial steps of the process for making a bag such as shown in FIG. 10 is shown in FIGS. 11 and 12 and is identical to that apparatus shown in FIGS. 8 and 9 except that at the adhesive applying station 86, the adhesive applying roll 88 is designed to apply an additional line 114 of adhesive to the web 82 for the purpose of bonding the intermediate strip 108 of each blank to the web 96 which eventually becomes the closure strip 30 of each blank. The strip 114 of adhesive is narrower than the spacing between the two slits defining the intermediate strip so that the adhesive does not contaminate the edges of the slits. Also, at the slitting station 90, the slitting roll 92 is designed to make two lengthwise slits 104 and 106 in the web 82 as well as the transverse slit 112, and the transverse slit 113 if used, for each blank. After the marrying operation performed at the station 94, the composite web is cut, folded and sealed, as previously described, to form the finished bags.

It will, of course, be understood that as far as finished bags are concerned, the present invention is not strictly limited to the particular constructions shown in FIGS. 6 and 7 and FIG. 10, and that instead the invention may be applied to many other different shapes, styles and forms of bags. For example, the bags shown in FIGS. 6 and 7 and in FIG. 10 are both bags which are provided with gussets along both longitudinal edges in order to provide for a relatively large amount of expansion of the bag from its flattened state. If desired, however, one or both of the gussets of each bag may be omitted; and FIG. 13 by way of example shows a blank 116 from which a bag having no side gussets may be made. The blank 116 of FIG. 13 is similar to the blank 10 of FIG. 1 except for omitting the gusset panels 42, 44, 46 and 48 of the blank 10. The various features of the blank 116 have, therefore, been given the same reference numerals as the corresponding features of the blank 10 of FIG. 1, except for such reference numerals being primed in FIG. 13. A finished bag is made from the blank 116 of FIG. 13 in the same manner as a finished bag is made from the blank 10 of FIG. 1 except that in folding the blank 116 the rear panel portion 50a' is first folded along the fold line 12' and the rear panel portion 50b' is then folded along the fold line 22' into partially overlying relationship with the portion 50a' to form the rear panel with no additional folds being required to define and provide gusset panel portions.

FIGS. 14 and 15 also by way of example show a still further form of bag which may incorporate the present invention. FIG. 14 at 118 shows a blank from which the finished bag of FIG. 15 is made. The blank 118 is generally similar to the blank 10 of FIG. 1 except for having a top edge 120 and a bottom edge 122 of somewhat different shapes than the corresponding top and bottom edges of the blank 10. Parts of the blank 118 which correspond to similar parts of the blank 10 of FIG. 1 have been given the same reference numerals as the blank 10 of FIG. 1, except for being double primed, and in general need not be further described. Although not shown in FIG. 14 it should be understood that the blank 118 includes a closure strip 30" extending the full length of the blank and located generally between the fold line 16" and the fold line 18".

In the case of the blank 118 of FIG. 14, it will be observed that the top edge 120 is of a shape precisely complementary to the bottom edge 122. Therefore, blanks identical to the illustrated blank 118 may be made by a web-forming process similar to that shown in FIGS. 8 and 9 and wherein the blanks are separated from the web by cutting or serrating the web along a transverse line having a shape similar to the edge 120 or the edge 122 of FIG. 14, each cut or serrated line so produced defining the bottom edge of one blank and the top edge of the next succeeding blank, or vice versa, without producing any waste. The blank 118 of FIG. 14 is in fact well adapted for use in making a serrated edge style of bag and for use in well-known equipment for making such bags. In this style of bag, the blanks for the bags are separated from the web by first being serrated along the eventual line of separation. Then, at a later station in the bag-forming machine, the forwardmost blank of the web is separated from the remainder of the web by being accelerated relative to the remainder of the web, causing it to be torn from the remainder of the web along the serrated line.

In comparing the blank 118 of FIG. 14 to the blank 10 of FIG. 1 it will be noted that the blank 118 below the fold line 26" is substantially similar in shape to the blank 10 below the fold line 26 of the blank 10, and after the blank 118 is folded along the vertical fold lines 12", 14", 16", 18", 20" and 22", it is folded along the horizontal fold line 26" in the same manner as the blank 10 to bring the various end flaps adjacent the fold line 26" into overlying relationship with the rear panel 50" to which they are adhesively or otherwise bonded, as shown in FIG. 15. However, above the upper horizontal fold line 24" the blank 118 differs from the blank 10 of FIG. 1 in that the front panel end flap 52" is of a shorter dimension, as measured along the length of the blank, than are the end flaps 60a" and 60b". Therefore, after the blank 118 is folded along the vertical fold lines 12", 14", 16", 18", 20" and 22", the end flaps adjacent the horizontal fold line 24" are folded, as shown in FIG. 15, in such a direction as to bring them into overlying relationship to the front panel 40" and closure strip 30" to which they are secured by a suitable adhesive or other bonding means.

Claims

I claim:

1. A filled and sealed bag of flexible sheet material which is easily opened to remove its contents, said bag comprising a rectangular rear panel, a rectangular front panel overlying said rear panel and of substantially the same size and shape as said rear panel, each of said front and rear panels having two parallel side edges and two parallel end edges, means joining said front panel to said rear panel along each of its four edges to the corresponding edge of said rear panel to form a pocket within which pocket the contents of said bag is received, said front panel having a slit therein located between and arranged generally lengthwise of its two side edges, said slit being located a substantial distance from each of said two side edges of said front panel, a closure strip of sheet material overlying said front panel and closing said slit, and bonding means securing said closure strip to said front panel while nevertheless allowing it to be peelably removed therefrom to expose said slit and to allow the contents of said pocket to be removed through said slit, said slit extending the full length of said front panel between said two end edges of said front panel, said closure strip overlying the full extent of said front panel, and said front panel having an end flap connected to each of its two end edges and said rear panel likewise having an end flap connected to each of its end edges, the end flaps of said front and said rear panel at each end edge of said front panel overlying one another and being folded about the associated end edge of said front panel so as to overlie a portion of said rear panel.

2. A bag as defined in claim 1 further characterized by the end flap of said front panel at each end edge of said front panel being longer in a direction perpendicular to such end edge than the associated end flap of said rear panel, and means adjacent each of said end edges of said rear panel for adhesively sealing the associated end flaps of said front and rear panels to said rear panel.

3. A bag as defined in claim 1 further characterized by said closure strip also including two end flaps each located at a respective one of said end edges of said front panel and folded around such end edge of said front panel so as to overlie the associated end flaps of said front and rear panels.

4. A bag as defined in claim 3 further characterized by said means for securing said closure strip to said front panel including a quantity of adhesive located in the vicinity of each of said end edges of said front panel and extending between said side edges of said front panel, at least one of said end flaps of said closure strip having a free edge parallel to its associated end edge of said front panel and said latter adhesive terminating short of said free edge so as to leave a portion of said closure strip end flap adjacent said free edge unsecured to the remainder of said bag enabling it to be grasped to initiate the peeling of said closure strip from said front panel.

5. A bag as defined in claim 4 further characterized by said means joining said front panel to said rear panel including at least two gusset panels extending along each of said side edges of said front panel and integrally connected with one another and with said front and rear panels by fold lines parallel to said side edges, said gusset panels when said bag is in a flattened condition being sandwiched between said front and rear panels and extending inwardly from said side edges of said front panel.

6. A bag as defined in claim 4 further characterized by said front panel having a second slit in addition to said first mentioned slit which second slit is arranged parallel to said first mentioned slit so as to define an intermediate strip of sheet material between said two slits, and means securing said intermediate strip to said closure strip so that as said closure strip is peeled from said front panel said intermediate strip is removed from said front panel with said closure strip to provide a mouth defined by the space previously occupied by said intermediate strip through which the contents of said pocket may be removed.

7. A bag as defined in claim 6 further characterized by said front panel including a third slit extending between said first two mentioned slits near one of said end edges of said front panel and defining one end of said intermediate strip.

8. A filled and sealed bag of flexible sheet material which is easily opened to remove its contents, said bag being made from a generally rectangular blank having two generally rectangular rear panel portions located respectively adjacent two opposite edges of such blank and also having a generally rectangular front panel located between said rear panel portions, said two rear panel portions of said blank being folded relative to the remainder of said blank into overlying relation with said front panel and into partially overlapping relation to one another, means bonding said two rear panel portions to one another within their zone of overlap and along a line generally parallel to said two opposite edges of said blank to form said two rear panel portions into a single rear panel, said front panel and said rear panel forming a pocket therebetween within which the contents of said bag is received, said front panel having a slit therein located between and arranged generally lengthwise of its two side edges, said slit being located a substantial distance from each of said two side edges of said front panel, a closure strip of sheet material overlying said front panel and closing said slit, and bonding means securing said closure strip to said front panel while nevertheless allowing it to be peelably removed therefrom to expose said slit and to allow the contents of said pocket to be removed through said slit.

9. A bag as defined in claim 8 further characterized by at least two gusset panels extending along each of said side edges of said front panel and integrally connected with one another and with said front and rear panels by fold lines parallel to said side edges, said gusset panels when said bag is in a flattened condition being sandwiched between said front and rear panels and extending inwardly from said side edges of said front panel.

10. A filled and sealed bag of flexible sheet material which is easily opened to remove its contents, said bag being made from a piece of flexible sheet material having two parallel edge portions positioned to overlap one another to form said piece of material into a generally tubular body the interior of which constitutes a pocket within which the contents of said bag is received, means bonding said two edge portions to one another within their zone of overlap along a line parallel to said edge portions, means for sealing the opposite ends of said generally tubular body, said piece of flexible material having a slit therein arranged generally parallel to and spaced from said edge portions, a closure strip of sheet material overlying and closing said slit, and bonding means securing said closure strip to said piece of material while nevertheless allowing it to be peelably removed therefrom to expose said slit and to allow the contents of said pocket to be removed through said slit.