US3570751A - Tear-open package - Google Patents

Abstract

A package formed by a sheet of flexible packaging material having a tear-open seam extending across a face or along an edge thereof. The tear-open seam is characterized by a flap formed by an edge of the package sheet and a tearable insert strip which secures the flap to the adjacent sheet edges. The method of making the package includes the steps of applying spaced transverse stripes of adhesive to a continuous flat web of packaging material, depositing articles to be packaged on the web between the applied adhesive stripes, folding the package web so that the edges thereof are disposed in overlying relation, introducing an adhesive coated insert web between the overlying web edges, sealing the transverse adhesive stripes, and cutting the web along the sealed adhesive stripes.

Description

United States Patent 72] Inventor Robert J. Trewella Reading, Pa. 211 Appl. No. 838,881 [22] Filed July 3, 1969 [4S] Patented Mar. 16, 1971 [73] Assignee Wyomissing Corporation Reading, Pa.

[54] TEAR-OPEN PACKAGE 14 Claims, 16 Drawing Figs.

[52] U.S. Cl 229/66, 229/51, 229/85 [51] Int. Cl B65d 17/20, B65d 65/26 [50] Field of Search 229/66, 51 (is), 85, 87, 40; 53/14; 93/(lTS) [56] References Cited UNITED STATES PATENTS 2,270,547 l/ 1942 Nichols 229/66X 3,249,288 5/1966 Repko 229/66 3,349,993 10/1967 Ellsetal. 3,456,867 7/l969 Repko Primary ExaminerDavid M. Bockener Att0rneyHowson and Howson ABSTRACT: A package formed by a sheet of flexible packaging material having a tear-open seam extending across a face or along an edge thereof. The tear-open seam is characterized by a flap formed by an edge of the package sheet and a teamble insert strip which secures the flap to the adjacent sheet edges.

The method of making the package includes the steps of applying spaced transverse stripes of adhesive to a continuous flat web of packaging material, depositing articles to be packaged on the web between the applied adhesive stripes, folding the package web so that the edges thereof are disposed in overlying relation, introducing an adhesive coated insert web between the overlying web edges, sealing the transverse adhesive stripes, and cutting the web along the sealed adhesive stripes.

PATENT ED MRI 6 ml SHEET 1 0F 3 BY ATTYS PATENTEU MAR] s IHYI SHEET 2 BF 3 ll a I Iaiil INVENTOR: ROBERT J. TREWELLA BY fizz/MW PATENTED MR1 s as?! SHEET 3 0F 3 INVENTOR:

ROBERT J. TREWELLA ATTYS,

1 TEAR-OPEN PACKAGE The present invention relates generally to packages formed of flexible packaging material and relates-specifically to a novel tear-open package and a method of making said package.

The invention includes a tear-open seam construction which is particularly adapted for use with flat paper packages such as the type employed for the packing of bandages and the like. A novel method of making such a package incorporating the present tear-open seam is included in the present invention.

Packages of the general type described incorporating tear- .open flaps have previously been used. However, in the con- I ventional package, the tear-open flap is adhesively secured. The opening of such a package is, as a result, somewhat unpredictable due to the vagaries of the adhesive bond. The amount of force required to tear open the adhesive-bonded seam is not uniform over the length of the seam and ripping of the flap may consequently occur.

In the present tear-open package, the tear is effected along a narrow, relatively low-strength area, such as a fold or score line, of an insert strip of tearable material and thus can be accomplished with a uniform force without danger of tearing the flap. The package comprises a tear-open seam which extends across a face or along an edge of the package and includes a flap formed by an edge of the package sheet and atearable insert strip which secures the flap to the adjacent sheet edge. The insert strip is adhesively secured to each of the adjacent sheet edges preferably with a score or fold'line therebetween along which the insert strip will predictably part upon application of force to the overlying flap. The adhesively secured insert strip portions serve to reinforce the adjacent sheet edges and accordingly prevent tearing of these edges. 7,

v The present method of making the'describedpackage'from a continuous web of packaging material includes in brief the steps of applying spaced transverse stripes of adhesive to a continuous flat web of packaging material, depositingarticles to be packaged on the web between the applied adhesive stripes, folding the package web so thatthe edges thereof are disposed in overlying relation, introducing an adhesive coated insert web between the overlying web edges, sealing the transverse adhesive stripes, and cutting the web along the sealed adhesive stripes to separate the filled packages.

It is accordingly a first object of the present invention to provide a package of flexible packaging material having a tear-open seam which may be easily openedalong its entire length by application of a moderate and uniform opening force.

Another object of the present invention is to provide a package as describe wherein the tear line is accurately established and wherein the regions adjacent thereto are reinforced to prevent inadvertent tearing thereof.

A further object of the invention is to provide a package as described which may with its contents be readily sterilized, and which will not jeopardize the sterility of the'contents during opening of the package and removal of the contents.

Still another object of the invention is to provide a package as described which is adapted for manufacture from continuous webs of packaging material. L

A still further object of the invention is to provide a method of making the described package in a rapid, economical and uniform manner. I

Additional objects and advantages of the invention. will be more readily apparent from the following detaileddescription of embodiments thereof when taken together with the accompanying drawings in which: I

FIG. 1 is a perspective view showing a packageformed in accordance with the present invention with one end edge unsealed to' reveal the configuration of the tear-openseam;

FIG. 2 is a perspective schematic view illustrating the present method of forming the package shown in FIG. 1;

FIGS. 3-6 are sectional views taken respectively along lines 3-3, 4-45, 5-5 and 6-6 of FIG. 2 showing the successive steps of folding the package web and insert web to form the desired sectional package configuration;

FIG. 7 is a plan view of the present package illustrating the manner in which the package is opened;

FIG. 8 is a sectional view taken along line 8-8 of FIG. 7;

FIG. 9 is a plan view of a modified form of the package, showing the package in the partially opened condition;

FIG. 10 is a sectional view taken along line lid-I0 of FIG. 9;

FIG. I1 is an enlarged view of the circled area of FIG. 10;

FIG. 12 is a plan view of a further modified form of the invention also shown in the partially openedcondition;

FIG. 13 is a sectional view taken along line 13-13 of FIG. 12;

FIG. 14 is a sectional view showing still another modified form of the present package;

FIG. 15 is a schematic elevational view further illustrating the novel method of making the preferred form of the invention; and

FIG. 16 is a schematic plan view showing a modified method of forming the present package.

Referring to the drawings, a;package 20 illustrating a preferred form of the invention is shown in FIGS. 7 and 8 and also, with one end unsealed, in FIG. 1. The package is formed of arectangular sheet 22 of flexible packaging material havingside edges 24 and 26 andend edges 28 and 30. Thesheet 22 is folded along parallel fold lines .32 and 33 parallel to and spaced from theside edges 24 and 26 to form a flattened tube, theside edge 26 overlapping theside edge 24. The fold lines and sheet edges thus define a package back panel 34,outer front panel 35, andinner front panel 36. Theend edges 28 and 30 are respectively sealed byadhesive layers 38 and 40 which preferably form peel-open bonds; thereby efiectively sealing the package except for the overlapped side edge region. It is in this region that the novel tear-open seam construction is ,employed. g

In the preferred embodiment, the tear-open seam includes aninsert strip 42 of tearable material which extends the full length of the overlapped side edges. Thestrip 42 is longitudinally folded into a U-shape along amedial fold line 43 and the oppositely facingpanels 44 and 45 thereof are adhesively bonded to the adjacent surfaces of the overlapped sheet side edges. The foldededge 43 of the insert strip is directed inwardly so that the outer edge 26'of the package sheet forms aflap 46 in conjunction with thestrip panel 44 which may be conveniently grasped to open the package.

FIGS. 7 and 8 illustrate the manner in which the tear-open seam is opened. The package is gripped adjacent thefold line 32 with one hand and by theflap 46 with the other hand. Upon movement of the hands apart with a moderate uniform force, the insert strip will tear cleanly along itsfold line 43. The in sert strip will tear at its fold line along the entire length of the seam since in view of the adhesive attachment of the adjacent strip panels to the sheet edges, this is the weakest point of the insert strip.

After the insert strip has been completely severed, the entireouter front panel 35 may be fully opened by peeling open the associated portions of theend seams 38 and 401.0 expose the package contents. By positioning theinsert strip 42 in outwardly spaced relation from thesheet edge 24, an inwardly extendingflap 48 formed by the sheet edge will, after opening of the tear-open seam, prevent contact of the packaged article with the insert strip during removal of the article from the package. It is thus possible to remove sterile articles from the package without contamination.

A novel method of making the above-described package is illustrated in FIGS. 2-6 and in FIG. 15. In this method, thepackage sheet 22 and theinsert strip 42 are supplied in continuously moving web form and the package is filled and formed in a continuous operation. Referring to FIG. 15, the

,package web 22 is advanced by feed rolls 5% into an adhesive appiicator 52, in which a heat-sensitive adhesive is applied in spaced transverse stripes 54 to the upper surface of the web. The web then passes beneath thefeeder 56 which sequentiallydeposits articles 58 to be packaged on the web surface between the adhesive stripe 5d. The package web bearing the articles to be packaged is then passed through the formers 6%,

62 and 64, the former 60 forming thefold 32 in the web. Between the formers 60 and 62, theinsert strip web 42 is introduced from above, passing beneath the roll 66 spaced above the package web. Theweb 42 is precoated with a liquid adhesive on the surface facing away from the roll 66. The former 62 forms thefold 43 in theinsert web 42 and combines the two webs, while the former 64 forms thefold 33 in the package web and completes the formation of the package tube. The manner in which these folds are formed is schematically shown in FIG. 2, the formers being omitted to more clearly show the formation of the several folds. Upon emerging from the formers, the combined webs have the sectional tubular configuration shown in FIG. 6.

After passage through the formers, the combined webs are presented to theheat seal station 70 wherein the transverse adhesive stripes 54 are sealed. From the heat seal station, the webs pass beneath the rotary knives 72 located between draw rolls 74 which cut the webs into the individual sealed packages by severing the webs along lines passing medially trough the adhesive stripes 54. By use of the described method, the present tear-open package can be rapidly and efficiently manufactured.

A modified method of making the present package is schematically shown in FIG. 16. In the modified method, the package is not filled during manufacture and the step of feeding the articles onto the package web is accordingly omitted. The method is othervw'se identical to that described above with two additional steps. The first is the provision of a longitudinal heat-scalable adhesive stripe 76 on the package web adjacent thefold line 33. The second is the longitudinal slitting of the package web along the adhesive stripe 76 at the slitting station 77 shown between theheat seal station 70 and the cutoff station 72. The slitting station 77 may alternately be located before the heat seal station. The package 78 resulting from this method is a bag-shaped enclosure having an open end 79 which may be heat sealed in a conventional manner after filing the package. The package incorporates the same tear-open seam described above in connection with the preferred package embodiment.

A modified form of the present package is illustrated in FIGS. 9-11 and is similar to that illustrated in FIGS. 1, 7 and 8 except that the insert strip 42' is not folded. Instead, thefront panel 35 is doubled back at fold line 35a to form a flap portion 35b underlying the adhesively bondedinsert strip panel 44. The edge of panel 36' extends in offset fashion beneath a portion of the doubled backpanel 35 asflap 48. Thestrip 42 is preferably scored along a score line 42a as shown in FIG. 11 to insure a tearing of the seam along this line when the package is opened as shown in FIG. 9. The score line although desirable is not essential since the insert web will be weakest along this line due to the reinforcing effect of the adhesive bonds with the package edges over the remainder of its area.

In the additional modified embodiment shown in FIGS. 12 and 13, thepackage 80 is formed of a package sheet 81 folded in half alongfold line 82 which defines one side edge of the package. The opposite side edge is formed by the tear away seam which includes aU-shaped insert strip 84 adhesively bonded between theoverlying edges 85 and 86 of the sheet 81, the folded edge 84a of the insert strip being inwardly directed. By grasping the sheet edges 85 and 86, the seam may be torn open uniformly along the fold 84a of the insert strip as illustrated in FIG. I2. As in the case of the previously described embodiments, the adhesively bonded insert strip reinforces the package sheet edges and prevents inadvertent tearing of the edges.

FIG. 14 still another embodiment of the present package is illustrated in section. This embodiment is identical with that of FIGS. 1, 7 and 8 except that theinsert strip 42" is not folded. Instead, a longitudinal medial score line 42b is provided on one side of the strip. The strip is, as in the preferred form, adhesively bonded to the opposed package edge surfaces, but the adhesive is applied to opposite faces of the strip. Opening of the package is effected in the manner shown in FIGS. 7 and 8, the tearing of the insert strip taking place along the score line 42b.

From the foregoing description of embodiments of the invention, it can be understood that the insert strip tear occurs along a narrow region of the strip which is not adhesively bonded to a package edge, which region may include a fold line or score line. The unsecured region is relatively weak compared to the adjacent adhesively bonded portions, particularly if folded or scored, and the strip will thus tear evenly along this narrow region.

The materials from which the package sheet and insert strip can be formed encompass a wide variety of flexible packaging materials such as paper, foils, films and the like. The insert strip is preferably of a weaker material than the packaging sheet although it could be of the same material if it may be readily torn.

The adhesives utilized in forming the package similarly may be of any suitabletype and need not be limited to the liquid and heat-scalable adhesives described.

The shape, size and type of package with which the present tear-open seam is employed may of course be varied from that of the illustrated embodiments. Two or more tear-open seams of the type described could be employed in the same package panel to permit the complete removal of the panel to provide access to the package contents. Similarly, although the tearopen seam of the illustrated embodiments is a straight line seam, the seam could have a curved configuration or could continue around several edges of the tear-open panel.

Manifestly, changes in details of construction can be effected by those skilled in the art without departing from the spirit and scope of the invention as defined in and limited solely by the appended claims.

Iclaim:

I. In a package formed of flexible packaging material and including adjacent parallel edges, the improvement of a tearopen seam comprising an insert strip of tearable material adhesively bonded to each of said adjacent edges, said insert strip having an unsecured region extending longitudinally thereof between the regions of adhesive attachment to said edges, one of said edges forming a flap which may be grasped to tear open said seam along the unsecured region of said insert strip said flap including a portion of said insert strip, the package side edges and the edges of said insert strip being mutually reinforced by their adhesive attachment thereby restricting the tearing of the seam to the unsecured region of said insert strip.

2. The invention as claimed in claim 1 wherein said insert strip includes a longitudinal score line in said unsupported region.

3. The invention as claimed in claim I wherein said insert strip includes a fold line in said unsupported region.

4. The invention as claimed in claim 1 wherein said edges are in overlapped relation with said insert strip being bonded between the overlapped portions thereof.

5. The invention as claimed in claim 4 wherein said insert strip is folded along a longitudinal fold line in said unsupported region into a U-shape, said fold line being directed inwardly of said seam.

6. The invention as claimed in claim 5 wherein the underlying edge extends inwardly of said insert strip to prevent contact of the package contents with said insert strip during removal thereof.

7. A tear-open package comprising flexible packaging material having a pair of parallel side edges and a pair of parallel end edges perpendicular thereto, said material being folded along each of a pair of parallel fold lines parallel to and spaced from said side edges toprovide an overlapping of said side edges, means forming a tear-open seam along said overlapped side edges, said means comprising an insert strip of tearable material disposed between and adhesively bonded to each of said overlapping side edges, said insert strip extending the length of said side edges and having an unsecured region extending longitudinally thereof between the areas of adhesive attachment to said side edges, one of said said edges and a portion of said insertstrip forming a flap which may be grasped to tear open said seam, said side edges and the edges of said insert strip being mutually reinforced by their adhesive attachment to thereby restrict the tearing of the seam to the unsecured region of the insert strip, and means for sealing the end edges of said package.

8. The invention as claimed in claim 7 wherein said means for sealing the end edges of said package provides a peel-open seal of said edges.

9. The invention as claimed in claim 7 wherein said insert strip is folded along a longitudinal fold line in said unsupported region into a U-shaped,said fold line being directed inwardly of said seam.

10. The invention as claimed in claim 9 wherein the underlying side edge extends inwardly of said insert strip to prevent contact of the package contents with said insert strip during removal thereof.

11. The invention as claimed in claim 7 wherein said insert strip includes a longitudinal score line in said unsupported region.

12. A tear-open package comprising a sheet of flexible packaging material having a medial fold line therein defining one package edge, the sheet edges parallel with said fold line being in parallel overlying relation and comprising a tear-open seam, said tear-open seam comprising an insert strip of tearable material disposed between and adhesively bonded to each of said overlying side edges, said insert strip being folded along a longitudinal fold line into a U-shape, said fold line being directed inwardly of said seam, each of said sheet side edges and a portion of said insert strip forming a flap which may be grasped to tear open said seam along the fold line of said insert strip, and means for sealing the ,end edges of said package sheet.

- 13. A tear-open package comprising a sheet of flexible packaging material having a pair of parallel side edges and a pair of parallel end edges perpendicular thereto, said sheet being folded along each of a pair of parallel fold lines parallel to and spaced from said sheet side edges to form a package back panel and a pairof package front panels, one of said front panels being folded along a line parallel with said fold lines to form an outwardly overlying flap portion thereof, said latter fold line overlying the side edge of the other of said front panels, a strip of tearable material extending longitudinally along and adhesively bonded to each of said front panels, said strip extending the length of said side edges and having an unsecured region extending longitudinally thereof between the areas of adhesive attachment to said front panels, said strip being attached to said one panel along the flap portion thereof, said front panels and the edges of said strip of tearable material being mutually reinforced by their adhesive attachment whereby the application of force to said flap causes a tearing of said sheet along the unsecured region of said strip, and means for sealing the end edges of said package sheet.

14. The invention as claimed inclaim 13 wherein said strip includes a score line in said unsecured region.

Claims (14)

1. In a package formed of flexible packaging material and including adjacent parallel edges, the improvemeNt of a tear-open seam comprising an insert strip of tearable material adhesively bonded to each of said adjacent edges, said insert strip having an unsecured region extending longitudinally thereof between the regions of adhesive attachment to said edges, one of said edges forming a flap which may be grasped to tear open said seam along the unsecured region of said insert strip said flap including a portion of said insert strip, the package side edges and the edges of said insert strip being mutually reinforced by their adhesive attachment thereby restricting the tearing of the seam to the unsecured region of said insert strip.

2. The invention as claimed in claim 1 wherein said insert strip includes a longitudinal score line in said unsupported region.

3. The invention as claimed in claim 1 wherein said insert strip includes a fold line in said unsupported region.

4. The invention as claimed in claim 1 wherein said edges are in overlapped relation with said insert strip being bonded between the overlapped portions thereof.

5. The invention as claimed in claim 4 wherein said insert strip is folded along a longitudinal fold line in said unsupported region into a U-shape, said fold line being directed inwardly of said seam.

6. The invention as claimed in claim 5 wherein the underlying edge extends inwardly of said insert strip to prevent contact of the package contents with said insert strip during removal thereof.

7. A tear-open package comprising flexible packaging material having a pair of parallel side edges and a pair of parallel end edges perpendicular thereto, said material being folded along each of a pair of parallel fold lines parallel to and spaced from said side edges to provide an overlapping of said side edges, means forming a tear-open seam along said overlapped side edges, said means comprising an insert strip of tearable material disposed between and adhesively bonded to each of said overlapping side edges, said insert strip extending the length of said side edges and having an unsecured region extending longitudinally thereof between the areas of adhesive attachment to said side edges, one of said said edges and a portion of said insert strip forming a flap which may be grasped to tear open said seam, said side edges and the edges of said insert strip being mutually reinforced by their adhesive attachment to thereby restrict the tearing of the seam to the unsecured region of the insert strip, and means for sealing the end edges of said package.

8. The invention as claimed in claim 7 wherein said means for sealing the end edges of said package provides a peel-open seal of said edges.

9. The invention as claimed in claim 7 wherein said insert strip is folded along a longitudinal fold line in said unsupported region into a U-shaped, said fold line being directed inwardly of said seam.

10. The invention as claimed in claim 9 wherein the underlying side edge extends inwardly of said insert strip to prevent contact of the package contents with said insert strip during removal thereof.

11. The invention as claimed in claim 7 wherein said insert strip includes a longitudinal score line in said unsupported region.

12. A tear-open package comprising a sheet of flexible packaging material having a medial fold line therein defining one package edge, the sheet edges parallel with said fold line being in parallel overlying relation and comprising a tear-open seam, said tear-open seam comprising an insert strip of tearable material disposed between and adhesively bonded to each of said overlying side edges, said insert strip being folded along a longitudinal fold line into a U-shape, said fold line being directed inwardly of said seam, each of said sheet side edges and a portion of said insert strip forming a flap which may be grasped to tear open said seam along the fold line of said insert strip, and means for sealing the end edges of said package sheet.

13. A tear-open package comprising a sheet of flexible packaging material haVing a pair of parallel side edges and a pair of parallel end edges perpendicular thereto, said sheet being folded along each of a pair of parallel fold lines parallel to and spaced from said sheet side edges to form a package back panel and a pair of package front panels, one of said front panels being folded along a line parallel with said fold lines to form an outwardly overlying flap portion thereof, said latter fold line overlying the side edge of the other of said front panels, a strip of tearable material extending longitudinally along and adhesively bonded to each of said front panels, said strip extending the length of said side edges and having an unsecured region extending longitudinally thereof between the areas of adhesive attachment to said front panels, said strip being attached to said one panel along the flap portion thereof, said front panels and the edges of said strip of tearable material being mutually reinforced by their adhesive attachment whereby the application of force to said flap causes a tearing of said sheet along the unsecured region of said strip, and means for sealing the end edges of said package sheet.

14. The invention as claimed in claim 13 wherein said strip includes a score line in said unsecured region.

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