US3554437A

US3554437A - Multiwall paper bag with ripcord

Info

Publication number: US3554437A
Application number: US824912A
Authority: US
Inventors: Vale G Kimsey
Original assignee: Bemis Co Inc
Current assignee: Amcor Flexibles North America Inc
Priority date: 1969-05-15
Filing date: 1969-05-15
Publication date: 1971-01-12
Anticipated expiration: 1988-01-12

Abstract

A multiwall paper bag having a ripcord extending endwise of the bag between the lapping margins of the longitudinal seam of the inner ply of the bag with its ends adhered to the inner ply but free of inner ply throughout a major portion of its length between its ends.

Description

United States Patent Inventor Vale G. Kimsey Vancouver, Wash.

Appl. No. 824,912

Filed May I5, 1969 Patented Jan. 12, 1971 Assignee Bemis Company, Inc.

Minneapolis, Minn. a corporation of Missouri MULTIWALL PAPER BAG WITH RIPCORD 2 Claims, 7 Drawing Figs.

U.S. Cl 229/66 Int. Cl B6541 27/38 Field of Search 229/66,

Slis, SlAs, 515,55, 86

[56] References Cited UNITED STATES PATENTS 2,106,475 1/1938 Brandwein 229/5 lSUX 2,923,456 2/1960 Ryan 229/66X 2,943 ,781 7/1960 Goodrich 229/66 FOREIGN PATENTS 853,924 1 1/1960 Great Britain 229/66 7 Primary Examiner-David M. Bockenek AttorneyKoenig, Senniger, Powers and Leavitt ABSTRACT: A multiwall paper bag having a ripcord extending endwise of the bag between the lapping margins of the longitudinal seam of the inner ply of the bag with its ends adhered to the inner ply but free of inner ply throughout a major portion of its length between its ends.

PATENTEH JAN I 2 I971 SHEET 1 BF 2 -PLL PATENTED JAN 1 2 I971 3 554 7 SHEET 2 or 2 MULTIWALL PAPER BAG WITH RIPCORD BACKGROUND OF THE INVENTION This invention relates to bags with a ripcord, and more particularly to multiwall paper bags with a ripcord for tearing an opening in a wall of the bag extending endwise of the bag.

The invention is particularly concerned with the problem of providing a multiwall paper bag with a ripcord, as distinguished from a tear strip such as shown in US. Pat. No. 2,943,781, adapted to tear a neat narrow slit in a wall of the bag extending endwise of the bag. I-leretofore, it has been regarded as impractical to provide a ripcord for a multiwall paper bag because of problems arising from the fact that such bags are made from a plurality of webs of heavy strong paper (e.g., kraft paper). Reference may be made to said US Pat. No. 2,943,781 for a discussion of the-problems involved in providing a ripcord in a multiwall'paper bag, and disclosing the provision of a tear strip in the form of a band or bands of adhesive between the plies, as distinguished from a ripcord.

SUMMARY OF THE INVENTION Accordingly, among the several objects of this invention may be noted the provision of a multiwall paper bag with a ripcord adapted to tear a neat clean slit in one of the walls of the bag through all the plies of that wall with the slit extending endwise of the bag; and the provision of such a bag wherein the ripcord is so disposed that it may be readily incorporated in the bag in the course of the manufacture of the tubing from which the bags are formed.

In general, a multiwall paper bag of this invention is formed from a multiply tube in which each ply has a longitudinal ply seam formed by lapping margins of the ply adhered together throughout the length of the tube, the tube being closed at one end. A ripcord extends lengthwise of the tube from one end thereof to the other between the lapped margins of the inner ply of the bag. This cord has its ends adhered to the inner ply and is free of securement to the inner ply throughout at least a major portion of its length between its said adhered ends. A portion of all the plies at one end of the tube including the respective end portion of the lapped margins of the inner ply between which the respective end of the ripcord is adhered is adapted to be grasped and pulled for pulling the ripcord to tear a slit in all the plies extending lengthwise of the bag. Other objects and features will be in part apparent and in part pointed out hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view of the front of a bag tube from which a bag of this invention is made;

FIG. 2 is a view of the back of the FIG. 1 tube;

FIG. 3 is an enlarged fragment of FIG. I viewed on line 33 of FIG. I with parts broken away;

FIG. 4 is a section on line 4-4 of FIG. 3;

FIG. 5 is a section on line 5-5 of FIG. 3;

FIG. 6 is a view of the front of a completed bag; and

FIG. 7 is a view of the FIG. 6 bag as it appears when filled and closed at its mouth, and showing the ripcord partly ripped out.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, there is indicated at I in FIGS. 1 and 2 a multiply paper bag tube from which a multiwall paper bag of this invention is made. This is illustrated as a two-ply tube; it will be understood that it may comprise three or more plies. The inner paper ply is designated 3 and the outer paper ply is designated 5. Each ply has a longitudinal ply seam formed by lapped longitudinal margins of the ply adhered together throughout the length of the tube by a stripe of adhesive. The longitudinal seam of the inner ply is designated 7 and the longitudinal seam of the outer ply is designated 9. As is conventional in making multiwall paper bags, these seams are located in laterally offset relation in one wall of the tube referred to as the back wall, this being designated II. The other wall of the tube, i.e., the front wall, is designated 13. As shown, the inner ply longitudinal seam 7 is located generally centrally of the back wall II. The tube is shown as having gussets 15, but it will be understood that the invention is applica ble to a flat (i.e., a nongusseted) bag.

The lapped margins of the inner ply 3 in the inner ply longitudinal seam 7 are designated 17 and I9. Margin I7 is the inside one of the lapped margins, and margin 19 is the outside one of the lapped margins. These are adhered together throughout the length of the tube I by a stripe of adhesive indicated at 21. This stripe is narrower than the width of the overlap of the margins, and, as shown best in FIGS. 3 and 5. is offset from the edge 17a of the inside lapped margin I7 so as to leave a flap portion 17b of the inside lapped margin between the stripe 21 and edge 17a free'of the overlying portion of the outside lapped margin 19.

A ripcord 23 extends lengthwise of the tube I from one end thereof to the other between the lapped margins 17 and 19 of the inner ply 3. It has been found that use of a flat rayon yarn of 1,500 denier with 0 turns and 0 twist as the ripcord is particularly effective, but it will be understood that other types of cord may be suitable. In this regard, it will be understood that the term ripcord is intended to cover any narrow ripping element whether in the form of a string or a narrow strip or the like. The ripcord 23 extends along a line between the stripe of adhesive 21 and the edge 17a of the inside lapped margin 17, being in effect trapped between the flap portion 17b of the seam 7 and the overlying portion of margin I9.

The ends of the ripcord 23 at the ends of the tube I are adhered to the inner ply 3 while the ripcord is free of securement to the inner ply throughout at least a major portion of its length between its said adhered ends, and preferably free of securement to the inner ply from one adhered end thereof to the other. As shown best in FIGS. 3 and 4, the adhesive securement of each end of the ripcord to the inner ply may be by means of a spot of adhesive 25 between the flap portion 17b of the seam 7 and the overlying portion of margin I9. FIG. 3 shows this spot of adhesive 25 at the upper end of the tube and it will be understood that there is a similar spot 25 at the lower end of the tube. In a bag made from a gusseted tube which is 39 inches long and 13 inches wide, for example, each spot may extend about 2 inches inward from the respective end of the tube, leaving 35 inches of the ripcord free of the inner ply between the spots.

It will be understood that bag tubes such as indicated at I may be formed in conventional manner by combining two paper webs (in the case of two-ply tubes) in laterally offset relation, forming these webs into tubing with the offset longitudinal ply seams 7 and 9 by means of a conventional tuber, and segmenting the tubing into individual bug tubes 1. The spot of adhesive 25 may be applied to the inner ply web as it is fed through the tuber with these spots spaced at intervals corresponding to the bag tube length, and a continuous length of ripcord material applied, the ripcord material being segmented along with the tubes. I

As shown in FIGS. 6 and 7, the bag tube I is formed with a conventional pasted self-opening square bottom closure 27 (an S.O.S." bottom) comprising end flaps 29, a first side flap 31 and a second side flap 33 folded over on the first side flap 31. The second side flap 33 (i.e., the outside side flap) is constituted by part of the back wall 11 of the tube which includes the inner ply seam 7 and the ripcord 23. Two slits 35 are pro vided in the back wall 11 through all the plies extending inward (upward) from the bottom end of the tube 1 on opposite sides of the respective end of the ripcord. These slits define a tab 37 at the margin of the outside closure flap 33. This tab is left free of the underlying closure flap 31 (i.e., it is not adhered to flap 3!) so that it may be grasped and pulled to pull the ripcord 23. Suitable directions such as indicated at 39 may be printed on the bottom closure 27 to instruct the ultimate user to pull the tab.

FIG. 7 shows a completed bag as it appears when filled and closed at its mouth as indicated at 41. It will be observed that when the bag is filled, the bottom 27 is squared out (i.e., of rectangular form) presenting the tab 37 generally at the center of the bottom. On grasping and pulling the tab 37, the plies in the outside closure flap 33 are ripped through on lines extending inward from the ends of slits 35, thus tearing out a two-ply paper strip 43 from the flap 33, and this shortly tails off to the point where the ripcord 23 per se tears a neat clean slit 4] in the back wall 11 of the bag extending lengthwise of the bag generally centrally of the back wall 11. The tearing of this neat clean slit in the back wall is attributable to the ripcord being free of the inner ply, once past the adhesive 25 at the bottom of the bag, all the way to the adhesive 25 at the other end of the bag.

ln view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

lclaim:

l. A multiwall paper bag formed from a multiply tube in which each ply has a longitudinal ply seam formed by lapping margins of the ply adhered together throughout the length of the tube, said tube being closed atone end, and a ripcord extending lengthwise of the tube from one end thereof to the other between the lapped margins of the inner ply of the bag, said cord having its ends adhered to the inner ply and being free of securement to the inner ply throughout at least a major portion of its length between its said adhered ends, a portion of all the plies at one end of the tube including the respective end portion of the lapped margins of the inner ply between which the respective end of the ripcord is adhered being adapted to be grasped and pulled for pulling the ripcord to tear a slit in all the plies extending lengthwise of the bag, the margins of the inner ply in the longitudinal seam of the inner ply being adhered together by a stripe of adhesive narrower than the width of the overlap of said margins and offset from the edge of the inside one of said lapped margins, the ripcord extending along a line between the stripe of adhesive and said edge, the ends of the ripcord being adhered to the inner ply by spots of adhesive between said margins at the ends of the tube and the ripcord being free of the inner ply between said spots. the longitudinal seam of the inner ply and the ripcord extending lengthwise of one wall of the bag, the tube being closed at its said one end by a pasted closure comprising end flaps, a first side flap and a second side flap folded over on the first side flap, said second flap being constituted by part of said one wall, and said second flap being formed to provide a tab adapted to be grasped to pull the ripcord.

2. A multiwall paper bag as set forth in claim I wherein the tab is defined by a pair of slits extending inward from the margin of said second side flap on opposite sides of the respective end of the ripcord, said tab being free of the first side flap.

Claims

1. A multiwall paper bag formed from a multiply tube in which each ply has a longitudinal ply seam formed by lapping margins of the ply adhered together throughout the length of the tube, said tube being closed at one end, and a ripcord extending lengthwise of the tube from one end thereof to the other between the lapped margins of the inner ply of the bag, said cord having its ends adhered to the inner ply and being free of securement to the inner ply throughout at least a major portion of its length between its said adhered ends, a portion of all the plies at one end of the tube including the respective end portion of the lapped margins of the inner ply between which the respective end of the ripcord is adhered being adapted to be grasped and pulled for pulling the ripcord to tear a slit in all the plies extending lengthwise of the bag, the margins of the inner ply in the longitudinal seam of the inner ply being adhered together by a stripe of adhesive narrower than the width of the overlap of said margins and offset from the edge of the inside one of said lapped margins, the ripcord extending along a line between the stripe of adhesive and said edge, the ends of the ripcord being adhered to the inner ply by spots of adhesive between said margins at the ends of the tube and the ripcord being free of the inner ply between said spots, the longitudinal seam of the inner ply and the ripcord extending lengthwise of one wall of the bag, the tube being closed at its said one end by a pasted closure comprising end flaps, a first side flap And a second side flap folded over on the first side flap, said second flap being constituted by part of said one wall, and said second flap being formed to provide a tab adapted to be grasped to pull the ripcord.

2. A multiwall paper bag as set forth in claim 1 wherein the tab is defined by a pair of slits extending inward from the margin of said second side flap on opposite sides of the respective end of the ripcord, said tab being free of the first side flap.