Information
-
Patent Grant
-
6402379
-
Patent Number
6,402,379
-
Date Filed
Wednesday, May 16, 200123 years ago
-
Date Issued
Tuesday, June 11, 200222 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Adams, Schwartz & Evans, P.A.
-
CPC
-
US Classifications
Field of Search
-
International Classifications
-
Abstract
A bag includes first and second polyolefin walls with a thickness of between 3 and 12 mils. The bag has joined opposing side edges, opposing end edges, and at least one seal line proximate one of the end edges. The seal line extends laterally from one side edge to the other for sealing closed an end of the bag. The improvement in the bag is a perforated tear line defining an easy-open corner portion of the bag removable to form a pourer. The perforated tear line includes a vertical segment defined by a series of closely spaced perforations formed in the first and second walls of the bag and closer to one side edge of the bag than the other. The vertical segment extends in a straight path outwardly from the seal line and generally parallel to the closer side edge of the bag. An arcuate transition segment of perforations begins at an end of the vertical segment and extends in an arcuate path towards the closer side edge of the bag. A diagonal segment of perforations extends along a straight incline from an end of the arcuate transition segment towards the closer side edge of the bag. The vertical segment, arcuate transition segment, and diagonal segment cooperate to enable the corner portion of the bag to be torn in a progressive tearing motion to form a hole in the bag from which the contents can be poured.
Description
TECHNICAL FIELD AND BACKGROUND OF THE INVENTION
This invention relates generally to heavy duty plastic bags made from single or multi-ply polyolefin materials, such as LD, HD, and LLD polyethylene and polypropylene, as well as other woven or nonwoven, synthetic or non-synthetic materials. Such bags are typically used to package materials such as fiberglass insulation, salt, potting soil, small landscaping rocks, pet food and similar heavy materials. While the invention has particular application to bags with a capacity of from 20 to 100 pounds, the principle of the invention is applicable to bags of any size.
Conventional, heavy-duty bags of the prior art are typically cut along the top with a knife or other suitable tool to define a sufficiently large opening through which the contents of the bag are dispensed. In the absence of a cutting knife or tool, attempts to manually tear open the bag by hand are often futile, because of the relative thickness and durability of such bags. Once opened, the bag must generally be embraced with both arms, lifted and inverted to dispense the contents from an opening in or near the top of the bag. In many cases, this requires substantial physical effort, and sometimes results in inadvertent uncontrolled dumping or over-dumping of the contents.
Applicant's prior issued U.S. Pat. No. 5,593,229 describes a heavy duty bag with an easily-removable corner adapted for being hand-torn to form a hole for pouring contents from the bag. The preferred embodiments of the bag described in the '229 Patent include a perforated vertical tear line extending downwardly from a top end edge of the bag to a second tear line extending from the first tear line towards the near side edge of the bag. While this bag solved many problems of the prior art, certain disadvantages and limitations still existed. Principally, the corner of the bag remained relatively difficult to tear by hand at the junction of the first and second tear lines in the case of a diagonally extending second tear line, and along the entire length of the second tear line in the case an arcuate line. Where the second tear line extended diagonally towards the near side edge of the bag, the difficulty in tearing resulted from the lack of a smooth transition from the first tear line to the second tear line. The bag with the arcuate second tear line provided a better transition from the vertical first tear line, but required greater effort to remove the torn corner due to the formation of perforations directly against the machine direction of the bag.
SUMMARY OF THE INVENTION
Therefore, it is an object of the invention to provide a bag with an improved easy-open corner portion.
It is another object of the invention to provide a bag with a perforated tear line including one or more arcuate transition segments to facilitate tearing the bag along a predetermined path.
It is another object of the invention to provide a bag with a perforated tear line which includes relatively few perforations formed against, or generally perpendicular to, the machine direction of the bag; the “machine direction” being a direction extending longitudinally from one end edge of the bag to the other.
These and other objects of the present invention are achieved in the preferred embodiments disclosed below by providing an improved bag including first and second polyolefin walls with a thickness of between 3 and 12 mils. The bag has joined opposing side edges, opposing end edges, and at least one seal line proximate one of the end edges. The seal line extends laterally from one side edge to the other for sealing closed an end of the bag. The improvement in the bag is a perforated tear line defining an easy-open corner portion of the bag removable to form a pourer. The perforated tear line includes a vertical segment defined by a series of closely spaced perforations formed in the first and second walls of the bag and closer to one side edge of the bag than the other. The vertical segment extends in a straight path outwardly from the seal line and generally parallel the closer side edge of the bag. An arcuate transition segment of perforations begins at an end of the vertical segment and extends in an arcuate path towards the closer side edge of the bag. A diagonal segment of perforations extends along a straight incline from an end of the arcuate transition segment towards the closer side edge of the bag. The vertical segment, arcuate transition segment, and diagonal segment cooperate to enable the corner portion of the bag to be torn in a progressive tearing motion to form a hole in the bag from which the contents can be poured.
According to another preferred embodiment of the invention, the perforations of the tear line are between {fraction (1/16)}th inch and ⅜th inch long.
According to another preferred embodiment of the invention, the perforations of the tear line are between {fraction (1/16)}th inch and ⅜th inch apart from adjacent perforations.
According to another preferred embodiment of the invention, the arcuate transition segment of the tear line is less than 20 percent of the overall length of the tear line.
According to another preferred embodiment of the invention, the arcuate transition segment of the tear line defines a radius of approximately 2 inches.
According to another preferred embodiment of the invention, the diagonal segment of the tear line extends from the arcuate transition segment at an angle less than 60 degrees to the closer side edge of the bag.
According to another preferred embodiment of the invention, the diagonal segment of the tear line extends from the arcuate transition segment at a 45 degree angle to the closer side edge of the bag.
According to another preferred embodiment of the invention, the tear line has a second arcuate transition segment of perforations beginning at an end of the diagonal segment and extending in an arcuate path towards the closer side edge of the bag.
According to another preferred embodiment of the invention, the tear line has a horizontal segment of perforations beginning at an end of the second arcuate transition segment and extending in an arcuate path towards the closer side edge of the bag.
According to another preferred embodiment of the invention, the first and second arcuate transition segments of the tear line each define a radius of approximately 1 inch.
According to another preferred embodiment of the invention, a second seal line is spaced-apart from the first seal line and extends laterally from one side edge of the bag to the other. A handle is formed in an area between the two spaced-apart seal lines.
According to another preferred embodiment of the invention, the handle is a generally U-shaped, die-cut slit.
BRIEF DESCRIPTION OF THE DRAWINGS
Some of the objects of the invention have been set forth above. Other objects and advantages of the invention will appear as the description proceeds when taken in conjunction with the following drawings, in which:
FIG. 1
is a view of a heavy-duty thermoplastic bag according to one preferred embodiment of the invention, and showing the bag prior to filling;
FIG. 2
is an enlarged, fragmentary view showing a corner portion of the bag;
FIG. 3
is a fragmentary view of the bag showing the corner portion of the bag being removed;
FIG. 4
is an enlarged, fragmentary view showing a corner portion of a bag according to a second preferred embodiment of the invention;
FIG. 5
is an enlarged, fragmentary view showing a corner portion of a bag according to a third preferred embodiment of the invention; and
FIG. 6
is an enlarged, fragmentary view showing a corner portion of a bag according to a fourth preferred embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT AND BEST MODE
Referring now specifically to the drawings, a bag according to the present invention is illustrated in FIG.
1
and shown generally at reference numeral
10
. Bags of the type disclosed are used for heavy-duty applications, such as for transport, sale, and storage of materials such as fiberglass insulation, salt, fertilizer, lawn lime, potting soil, and the like. The bags are typically fabricated from a polyolefin sheet or tube stock such as polyethylene or polypropylene having a thickness in the range of 3 to 12 mils. The sheet or tube stock may be coextruded or monoextruded, and may be single ply or multi-ply material. The multi-ply material may be multiple thicknesses of the same sheet or tube stock, or different materials to provide particular characteristics, such as strength, flexibility, UV resistance, or color. The sheet stock may also be woven or non-woven synthetic or non-synthetic material.
Bag
10
is formed from thermoplastic sheet or tube stock, and has overlying front and back walls
11
and
12
, defining opposing joined side edges
13
and
14
. The term “joined” is used in a broad sense to mean either two formerly separate sheets connected together, or integrally formed by, for example, folding over a sheet to define an edge. For purposes of example and illustration, bag
10
is a flat tube-type bag. However, bags incorporating the present invention may be fabricated in a side-gusset tube style, flat tube back-seamed style, side gusset back seam style, or any other suitable bag design.
The thermoplastic walls
11
and
12
are connected together proximate the top end edge
15
of the bag
10
by a lateral seal line
16
extending from side edge
13
to side edge
14
. The seal line
16
is formed by adhesive, sewing, ultrasonic heating, or other heat-fusing process. In the embodiment of
FIGS. 1-3
, a second seal line
17
is formed below the first seal line
16
and defines the upper closure of the contents-holding portion of the bag
10
. A generally U-shaped slit
18
is die-cut into the area between the seal lines
16
and
17
to form a carry handle when the hand is extended through the slit
18
. The bottom end edge
19
of the bag
10
remains open for filling.
As best shown in
FIG. 2
, the bag
10
includes a line
21
of closely-spaced perforations formed in each of the walls
11
and
12
, and defining an easy-open corner portion of the bag
10
removable by hand to form a pourer. The perforated tear line
21
includes a vertical segment
21
A extending in a straight path downwardly from the top end edge
15
of the bag
10
and generally parallel to the closer side edge
13
. An arcuate transition segment
21
B begins at an end of the vertical segment
21
A and extends in a generally concave arcuate path towards the closer side edge
13
of the bag
10
. The arc radius “R” of this segment
21
B is preferably about 2 inches. Finally, a diagonal segment
21
C is formed along a straight incline from an end of the arcuate transition segment
21
B to the closer side edge
13
. The diagonal segment
21
C extends at an angle “A” of 45 degrees relative to the side edge
13
. According to this embodiment, the overall length of the tear line
21
is 10.8 inches with the arcuate transition segment
21
B comprising approximately 14 percent of this length; the length of the vertical segment
21
A being 3.7 inches, the arcuate transition segment
21
B being 1.5 inches, and the diagonal segment
21
C being 5.5 inches. The lateral distance “D
1
” from the side edge
13
of the bag
10
to a top end of the perforated tear line
21
is 4.5 inches. The vertical distance “D
2
” from the top end edge
15
of the bag
10
to the bottom end of the tear line
21
is 9 inches.
As shown in
FIG. 3
, the bag
10
is opened by gripping the top end edge
15
and pulling the bag
10
apart on opposite sides of the tear line
21
. A progressive tearing motion starts at the top end of the tear line
21
and extends into the vertical segment
21
A causing the lands between the perforations to rupture. The tear extends down the vertical segment
21
A and then into the arcuate transition segment
21
B. Because of the curved pattern of perforations in the arcuate transition segment
21
B, the tear easily transitions into the diagonal segment
21
C with relatively little added physical effort, and without deviating from the predetermined path defined by the tear line
21
. From the transition segment
21
B, the tear extends at an incline along the diagonal segment
21
C to the side edge
13
of the bag
10
. The corner portion is thus completely severed from the bag
10
. A pourer is formed in the corner of the bag
10
through which the contents can be poured. Material can be poured from the bag
10
with complete visibility and without diverting the flow of material, because the bag material severed to form the opening is completely removed and discarded.
Further embodiments of the invention are illustrated in
FIGS. 4-6
.
FIG. 4
shows a bag
30
similar to the bag
10
, but without a second seal line or handle. Bag
30
includes a line of closely-spaced perforations
31
formed in each of the bag walls, and defining an easy-open corner portion of the bag
30
removable by hand to form a pourer. The perforated tear line
31
includes a vertical segment
31
A extending in a straight path downwardly from the top end edge of the bag
30
and generally parallel to the closer side edge. An arcuate transition segment
31
B begins at an end of the vertical segment
31
A and extends in a generally concave arcuate path towards the closer side edge of the bag
30
. The arc radius “R” of this segment
31
B is preferably about 2 inches. A diagonal segment
31
C is formed along a straight incline from an end of the arcuate transition segment
31
B to the closer side edge. The diagonal segment
31
C extends at an angle “A” of 45 degrees relative to the side edge. The overall length of the tear line
31
is 9.1 inches with the arcuate transition segment
31
B comprising approximately 17 percent of this length; the length of the vertical segment
31
A being 2.0 inches, the arcuate transition segment
31
B being 1.6 inches, and the diagonal segment
31
C being 5.5 inches. The lateral distance “D
1
” from the side edge of the bag
30
to atop end of the perforated tear line
31
is 4.5 inches. The vertical distance “D
2
” from the top end edge of the bag
30
to the bottom end of the tear line
31
is 7.3 inches.
The bag
40
shown in
FIG. 5
includes first and second spaced apart seal lines
41
and
42
, and a die-cut handle
45
formed between the seal lines. A line of closely-spaced perforations
51
is formed in each of the bag walls, and defines an easy-open corner portion of the bag
40
removable by hand to form a pourer. The perforated tear line
51
includes a vertical segment
51
A extending in a straight path downwardly from the top end edge of the bag
40
and generally parallel to the closer side edge. A first arcuate transition segment
51
B begins at an end of the vertical segment
51
A and extends in a generally concave arcuate path towards the closer side edge of the bag
40
. The arc radius “R” of this segment
51
B is preferably about 1 inch. A diagonal segment
51
C is formed along a straight incline from an end of the first arcuate transition segment
51
B to a second arcuate transition segment
51
D. The diagonal segment
51
C extends at an angle “A” of 45 degrees relative to the side edge. The arc radius “R
2
” of the second transition segment
51
D is also about 1 inch. Finally, a relatively short horizontal segment
51
E extends from the second arcuate transition segment
51
D to the side edge of the bag
40
. The overall length of the tear line
51
is 9.8 inches with the first and second arcuate transition segments
51
B,
51
D comprising approximately 16 percent of this length; the length of the vertical segment
51
A being 3.9 inches, the first arcuate transition segment
51
B being 0.8 inches, the diagonal segment
51
C being 3.0 inches, the second arcuate transition segment
51
D being 0.8 inches, and the horizontal segment
51
E being 1.3 inches. The lateral distance “D
1
” from the side edge of the bag
40
to a top end of the perforated tear line
51
is 4.5 inches. The vertical distance “D
2
” from the top end edge of the bag
40
to the bottom end of the tear line
51
is 7.0 inches.
FIG. 6
shows a bag
60
similar to the bag
40
of
FIG. 5
, but without a second seal line or handle. A line of closely-spaced perforations
61
is formed in each of the bag walls, and defines an easy-open corner portion of the bag
60
removable by hand to form a pourer. The perforated tear line
61
includes a vertical segment
61
A extending in a straight path downwardly from the top end edge of the bag
60
and generally parallel to the closer side edge. A first arcuate transition segment
61
B begins at an end of the vertical segment
61
A and extends in a generally concave arcuate path towards the closer side edge of the bag
60
. The arc radius “R
1
” of this segment
61
B is preferably about 1 inch. A diagonal segment
61
C is formed along a straight incline from an end of the first arcuate transition segment
61
B to a second arcuate transition segment
61
D. The diagonal segment
61
C extends at an angle “A” of 45 degrees relative to the side edge. The arc radius “R
2
” of the second transition segment
61
D is also about 1 inch. A relatively short horizontal segment
61
E extends from the second arcuate transition segment
61
D to the side edge of the bag
60
. The overall length of the tear line
61
is 9.1 inches with the first and second arcuate transition segments
61
B,
61
D comprising approximately 17 percent of this length; the length of the vertical segment
61
A being 3.1 inches, the first arcuate transition segment
61
B being 0.8 inches, the diagonal segment
61
C being 3.0 inches, the second arcuate transition segment
61
D being 0.8 inches, and the horizontal segment
61
E being 1.4 inches. The lateral distance “D
1
” from the side edge of the bag
60
to a top end of the perforated tear line
61
is 4.5 inches. The vertical distance “D
2
” from the top end edge of the bag
60
to the bottom end of the tear line
61
is 6.3 inches.
For each of the bags described above, the length of each perforation is approximately 0.1 inch. The length of the lands between perforations is approximately 0.25 inch. To facilitate tearing, the perforations at each end of the tear line preferably communicate with the top end edge of the bag and side edge, respectively.
A bag with an arcuate-transition tear line is described above. Various details of the invention may be changed without departing from its scope. Furthermore, the foregoing description of the preferred embodiment of the invention and the best mode of practicing the invention are provided for the purpose of illustration only and not for the purpose of limitation—the invention being defined by the claims.
Claims
- 1. In a bag including first and second walls having joined opposing side edges, opposing end edges, and at least one seal line proximate one of said end edges and extending laterally from one side edge to the other for sealing closed an end of the bag, the improvement comprising a perforated tear line defining an easy-open corner portion of the bag removable to form a pourer, said perforated tear line comprising:(a) a vertical segment defined by a series of closely spaced perforations formed in said first and second walls of said bag and closer to one side edge of said bag than the other, said vertical segment extending in a straight path outwardly from said seal line and generally parallel to the closer side edge of said bag; (b) a first arcuate transition segment defined by a series of closely spaced perforations formed in said first and second walls of said bag, and beginning at an end of said vertical segment and extending in an arcuate path towards the closer side edge of said bag; and (c) a diagonal segment defined by a series of closely spaced perforations formed in said first and second walls of said bag, and extending along a straight incline from an end of said arcuate transition segment towards the closer side edge of said bag; (d) a second arcuate transition segment defined by a series of closely spaced perforations formed in said first and second walls of said bag, and beginning at an end of said diagonal segment and extending in an arcuate path towards the closer side edge of said bag; and (e) a horizontal segment defined by a series of closely spaced perforations formed in said first and second walls of said bag, and beginning at an end of said second arcuate transition segment and extending in a straight path towards the closer side edge of said bag; whereby said vertical segment, first arcuate transition segment, diagonal segment, second arcuate transition segment, and horizontal segment cooperate to enable the corner portion of the bag to be torn in a progressive tearing motion to form a hole in the bag from which the contents can be poured.
- 2. A bag according to claim 1, wherein the arcuate transition segment of said tear line comprises less than 20 percent of the overall length of said tear line.
- 3. A bag according to claim 1, wherein said arcuate transition segment of said tear line defines a radius of approximately 2 inches.
- 4. A bag according to claim 1, wherein said first and second arcuate transition segments of said tear line each define a radius of approximately 1 inch.
- 5. A bag according to claim 1, wherein said diagonal segment of said tear line extends from said arcuate transition segment at an angle less than 60 degrees to said closer side edge.
- 6. A bag according to claim 1, wherein said diagonal segment of said tear line extends from said arcuate transition segment at a 45 degree angle to said closer side edge.
- 7. A bag according to claim 1, and comprising a second seal line spaced-apart from said first seal line and extending laterally from one side edge of said bag to the other, and further comprising a handle formed in an area between the two spaced-apart seal lines.
- 8. A bag according to claim 7, wherein said handle comprises a generally U-shaped, die-cut slit.
- 9. In a bag including first and second polyolefin walls with a thickness of between 3 and 12 mils and having joined opposing side edges, opposing end edges, and at least one seal line proximate one of said end edges and extending laterally from one side edge to the other for sealing closed an end of the bag, the improvement comprising a perforated tear line defining an easy-open corner portion of the bag removable to form a pourer, said perforated tear line comprising:(a) a vertical segment defined by a series of closely spaced perforations formed in said first and second walls of said bag and closer to one side edge of said bag than the other, said vertical segment extending in a straight path outwardly from said seal line and generally parallel to the closer side edge of said bag; (b) first arcuate transition segment defined by a series of closely spaced perforations formed in said first and second walls of said bag, and beginning at an end of said vertical segment and extending in an arcuate path towards the closer side edge of said bag; and (c) a diagonal segment defined by a series of closely spaced perforations formed in said first and second walls of said bag, and extending along a straight incline from an end of said arcuate transition segment towards the closer side edge of said bag; (d) a second arcuate transition segment defined by a series of closely spaced perforations formed in said first and second walls of said bag, and beginning at an end of said diagonal segment and extending in an arcuate path towards the closer side edge of said bag; and (e) a horizontal segment defined by a series of closely spaced perforations formed in said first and second walls of said bag, and beginning at an end of said second arcuate transition segment and extending in a straight path towards the closer side edge of said bag; whereby said vertical segment, first arcuate transition segment, diagonal segment, second arcuate transition segment, and horizontal segment cooperate to enable the corner portion of the bag to be torn in a progressive tearing motion to form a hole in the bag from which the contents can be poured.
- 10. A bag according to claim 9, wherein the perforations of said tear line are between {fraction (1/16)}th inch and ⅜th inch long.
- 11. A bag according to claim 9, wherein the perforations of said tear line are between {fraction (1/16)}th inch and ⅜th inch apart from adjacent perforations.
- 12. A bag according to claim 9, wherein said arcuate transition segment of said tear line comprises less than 20 percent of the overall length of said tear line.
- 13. A bag according to claim 9, wherein said arcuate transition segment of said tear line defines a radius of approximately 2 inches.
- 14. A bag according to claim 9, wherein said diagonal segment of said tear line extends from said arcuate transition segment at an angle less than 60 degrees to said closer side edge.
- 15. A bag according to claim 9, wherein said diagonal segment of said tear line extends from said arcuate transition segment at a 45 degree angle to said closer side edge.
- 16. A bag according to claim 9, wherein said first and second arcuate transition segments of said tear line each define a radius of approximately 1 inch.
US Referenced Citations (9)