U.S. patent number 3,570,751 [Application Number 04/838,881] was granted by the patent office on 1971-03-16 for tear-open package.
This patent grant is currently assigned to Wyomissing Corporation. Invention is credited to Robert J. Trewella.
United States Patent |
3,570,751 |
Trewella |
March 16, 1971 |
TEAR-OPEN PACKAGE
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.
Inventors: |
Trewella; Robert J. (Reading,
PA) |
Assignee: |
Wyomissing Corporation
(Reading, PA)
|
Family
ID: |
25278298 |
Appl.
No.: |
04/838,881 |
Filed: |
July 3, 1969 |
Current U.S.
Class: |
383/207; 383/66;
229/84; 383/107 |
Current CPC
Class: |
B31B
70/18 (20170801); B65D 75/5827 (20130101); B65D
75/46 (20130101) |
Current International
Class: |
B65D
75/58 (20060101); B65D 75/52 (20060101); B65D
75/00 (20060101); B65D 75/46 (20060101); B65d
017/20 (); B65d 065/26 () |
Field of
Search: |
;229/66,51 (IS)/
;229/85,87,40 ;53/14 ;93/(ITS) |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Bockener; David M.
Claims
I claim:
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.
Description
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 conventional
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 a tearable 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.
The present method of making the described package 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, 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 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 opened along 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.
A still further object of the invention is to provide a method of
making the described package in a rapid, economical and uniform
manner.
Additional objects and advantages of the invention will be more
readily apparent from the following detailed description of
embodiments thereof when taken together with the accompanying
drawings in which:
FIG. 1 is a perspective view showing a package formed in accordance
with the present invention with one end edge unsealed to reveal the
configuration of the tear-open seam;
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,
4-4, 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 10-10 of FIG. 9;
FIG. 11 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 opened condition;
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 a rectangular
sheet 22 of flexible packaging material having side edges 24 and 26
and end edges 28 and 30. The sheet 22 is folded along parallel fold
lines 32 and 33 parallel to and spaced from the side edges 24 and
26 to form a flattened tube, the side edge 26 overlapping the side
edge 24. The fold lines and sheet edges thus define a package back
panel 34, outer front panel 35, and inner front panel 36. The end
edges 28 and 30 are respectively sealed by adhesive layers 38 and
40 which preferably form peel-open bonds, thereby effectively
sealing the package except for the overlapped side edge region. It
is in this region that the novel tear-open seam construction is
employed.
In the preferred embodiment, the tear-open seam includes an insert
strip 42 of tearable material which extends the full length of the
overlapped side edges. The strip 42 is longitudinally folded into a
U-shape along a medial fold line 43 and the oppositely facing
panels 44 and 45 thereof are adhesively bonded to the adjacent
surfaces of the overlapped sheet side edges. The folded edge 43 of
the insert strip is directed inwardly so that the outer edge 26 of
the package sheet forms a flap 46 in conjunction with the strip
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 the fold line 32 with one
hand and by the flap 46 with the other hand. Upon movement of the
hands apart with a moderate uniform force, the insert strip will
tear cleanly along its fold line 43. The insert 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 entire
outer front panel 35 may be fully opened by peeling open the
associated portions of the end seams 38 and 40 to expose the
package contents. By positioning the insert strip 42 in outwardly
spaced relation from the sheet edge 24, an inwardly extending flap
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, the package sheet 22
and the insert 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 50 into an adhesive applicator 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 the
feeder 56 which sequentially deposits articles 58 to be packaged on
the web surface between the adhesive stripe 54. The package web
bearing the articles to be packaged is then passed through the
formers 60, 62 and 64, the former 60 forming the fold 32 in the
web. Between the formers 60 and 62, the insert strip web 42 is
introduced from above, passing beneath the roll 66 spaced above the
package web. The web 42 is precoated with a liquid adhesive on the
surface facing away from the roll 66. The former 62 forms the fold
43 in the insert web 42 and combines the two webs, while the former
64 forms the fold 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 the heat 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 20 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 otherwise
identical to that described above with two additional steps. The
first is the provision of a longitudinal heat-sealable adhesive
stripe 76 on the package web adjacent the fold line 33. The second
is the longitudinal slitting of the package web along the adhesive
stripe 76 at the slitting station 77 shown between the heat 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, the front panel
35' is doubled back at fold line 35a to form a flap portion 35b
underlying the adhesively bonded insert strip panel 44'. The edge
of panel 36' extends in offset fashion beneath a portion of the
doubled back panel 35' as flap 48'. The strip 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, the
package 80 is formed of a package sheet 81 folded in half along
fold line 82 which defines one side edge of the package. The
opposite side edge is formed by the tear away seam which includes a
U-shaped insert strip 84 adhesively bonded between the overlying
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. 12. 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 the insert 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 suitable type and need not be limited to the liquid and
heat-sealable 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 tear-open 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.
* * * * *