CA1279038C

CA1279038C - Attachment of plastic zipper to incompatible bag wall web

Info

Publication number: CA1279038C
Application number: CA000508620A
Authority: CA
Inventors: Steven Ausnit; Per Bentsen
Original assignee: Minigrip Inc
Current assignee: Minigrip Inc
Priority date: 1985-08-27
Filing date: 1986-05-07
Publication date: 1991-01-15
Anticipated expiration: 2008-01-15
Also published as: JPS6247303A; FR2588246A1; US4807300A; FR2588246B1; US4682366A

Abstract

ABSTRACT
Bags especially adapted to be made from fusibly incompatible bag body web material and extruded plastic zippers comprising in each instance a pair of zipper strips having reclosable zipper profiles located below upper ends of pull flanges, and fused connecting anchors extending from the zipper strips through holes in the material of the bag body and thereby permanently attaching the zipper strips to the bag body. The portions of the bag body material having the anchor holes may be received in groove sockets in the zipper strips, where the zipper strips are located at the inside of the bag. The zipper strips may be located on the outside of the bag and sealably pinch material of the bag body material in and between interlocking profiles, with ends of the zipper strips secured to the sides of the bag by fused anchors extending through holes in side seams on the bag body. Method of making the bags is disclosed.

Description

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SPEC IF ICATION
This invention relates to the art of bag making, and is more particularly concerned with bags having reclosable zippers of the extruded complementary rib and groove type.
Heretofore, numerous and varied bag structures of this type have been proposed and some have achieved sub-stantial commercial success.
For example, U.S. Patent Re. 28,969 discloses a bag structure in which the bag body web and the zipper profiles are extruded in one piece and the bag has pull flanges which project outwardly relative to the zipper.
In U.S. Patent 4,430,070 the zipper if fusibly attached to the bag wall web spaced inwardly from the pull flanges which project outwardly from the zipper.
Both of these examples require that the bag body web and the zipper profiles be fusibly compatible, that is that one can be fused onto the other by some sort of heat sealing means.
On the other hand, U.S. Patent 4,341,575 is repre-sentative of disclosures wherein zipper strips are attached to the bag wall web by adhesive means, and which would permit fusibly incompatible materials to be used. However, it will be noted that this disclosure requires fairly critical parameters in the adhesive attachement to avoid separation of the elements. Ahesive attachment generally involves some messiness due to the necessary manner of application of the adhesive to the elements.
Fused attachment of the elements is generally preferred, but presents a problem where the zipper strips and the bag body web are fusibly incompatible. For example, while polypropylene may be fused to polypropylene, and~

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1 polyethylene may be fused to polyethylene, there is great difficulty encountered in any attempt to fuse or heat seal polyethylene to polypropylene. In bags, while polyethylene is widely used, both for the bag body web material and also for the profiled zipper strips, for one thing because of the ease of extruding such material, the polyethylene material does not afford the imperviousness that is frequently desired where fluid barrier is required for either or both. Sometimes, also, other web material incompatible to fusing together with polyethylene may be desired, while the profiled zipper strips should be extruded from polyethylene.
It is to the problem of making bags from fusibly incompatible bag body web m~terial and extruded plastic profile zipper strips that the present invention is directed.
In the prior art, there has been the suggestion in U.S. Patent 2,791,807 that separable fastener stringers be constructed of extruded plastic profile fasteners attached to fabric stringer tapes so that the plastic strips may be attaclled by sewing the fabric tape stringers to the articles to which the fastener strips are desired to be secured. The structure in that patented disclosure does not lend itself to embodiment in bags, and more particularily bags made from plastic wall web material, and provided with pull flanges at their open tops.
It is, accordingly, an important object of the present invention to provide a new and improved bag structure made from fusibly incompatible bag wall web material and extruded plastic zipper and in which the bags are provided with pull flanges.

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Another ob~ect of the inventlon i9 to provide bag structure as ~ust indicated in which the fusibly incompatible bag wall web material and the extruded zipper are secured together by fusibly locking parts of the zipper to one another for securing the zipper to the bag wall web.
Accordingly, the present invention provides a bag having a thin web material body with an openable top flanked by opposed upwardly projecting pull flanges and extruded plastic zipper means carried by said body along said pull flanges, and wherein said bag body and said zipper means are fusibly imcompatible, said zipper means comprising a pair of ; strips having complementary separably interlockable zipper profiles located substantially below upper ends of said pull flanges, holes in said bag body material, and fused connecting anchors extending from said zipper strips through said holes and permanently attaching said zipper strips to ` said bag body.
The present invention also provides a method of making a bag equipped with extruded plastic realosable : 20 zipper means, comprising forming a bag body from thin web material and having an openable top flanged by opposed upwardly pro~ecting margins, providing extruded plastic zipper strips fusibly incompatable with the material of said bag body and comprising a pair of opposed strips having complementary separably interlockable zipper profiles, assembling said profile strips along said margins and with the profiles located substantially below upper ends of said margins, and permenently attaching said zipper strips to said bag body by fusibly connecting anchors from said zipper strips through holes in said bag body.
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' Aclditionally, the present invention provides a bag having a thin web material body with an openable top flanked by opposed upwardly projecting margins and an extruded plastic zipper means carried by said body along said margins, and wherein said zipper means comprise a pair of profiles having complementary separably interlockable zipper profiles below the upper ends of said margins, one of said zipper strips being located along the outsize of one side of the bag body and the other of said zipper strips being aligned so that their profiles are in matching relation, said material of said bag body and said zipper strips being fusibly incompatible, said bag body having portions thereof near said zipper strips provided with holes therethrough, and fused anchors extending into said holes and securing the zipper strips to said bag body.
ON THE DRAWINGS
Other objects, features and advantages of the invention will be readily apparent from the following description of representative embodiments thereof, taken in conjunction with the accompanying drawings, although variations and modifications may be effected without departing from the spirit and scope of the novel concepts embodied in the disclosure an in which:
FIG. l is a fragmental isometric view showing bag making material embodying the invention.
FIG. 2 is a fragmentary view similar to FIG.
l but showing a slight modification.
FIG. 2A is a modification of FIG. 2.

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1 FIG. 3 is a view similar to FIG. 2 but showing another slight modification.
FIG. 4 is an enlarged fragmentary sectional detail view taken substantially along the line IV-IV in FIG. 1.
FIG. 5 is a fragmental isometric view showing a further modification.
FIGS. 6-15, inclusive are fragmentary isometric, more or less schematic views showing how assembly and manipulation of the bag wall web and the fastener strips for the zipper are assembled and manipulated to arrive at the structure exemplifed in FIG. 5.
FIG. 16 is a fragmentary isometric view showing still another modification.
FIG. 17 is an enlarged fragmentary sectional detail view taken substantially along the line XVII-XVII in FIG. 16.
FIG. 18 is a fragmentary assembly view showing how the parts of the structure of FIG. 16 are adapted to be brought together; and FIG. 19 is a schematic fragmentary view demonstrating how the parts of FIG. 18 are finally secured together.
Throughout the description, it will be understood that various parts of the structure may, for illustrative purposes, be dimensionally exaggerated and that, as a ; 25 matter of fact, cross sectional dimensions as well as some other dimensions may in actual practice be on a much smaller scale. Dimensions may vary, as is well known in the art, depending upon strength factors required, uses to which the ultimate bags may be put, etc.

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1 Referring to ~IG. 1, a bag structure 20 is shown as though just completed in a continuous ribbon and before cross sealing and separating into individual bag sections.
The structure 20 comprises a bag wall web 21 folded upon itself to provide a closed bag bottom 22 and having upper end margins 22 between which is defined a bag mouth top opening 23. Alternately if an open bottom bag is desired, two separate bag walls can be used instead of one folded wall.
A reclosable zipper 24 is secured to the bag wall web 21 at the margins 22a. In a desirable form, the zipper 24 comprises complementary zipper strips 25 and 27 wherein each of the strips has a plurality of hook shaped ribs 28 which are releasibly interlocked with one another within complementary grooves 29. Each of the zipper strips 25 and 27 has along one longitudinal side a lateral base continuation in the form of a flange 30 which is of sufficient original width, as indicated in dash outline, to be folded upon itself to provide along the length of the zipper strip a flat socket 31 receptive of the respective associated bag wall web margin 22a. If preferred, the flanges 30 may be initially formed in the folded fashion to provide the sockets 31. In either event, the reentrant groove or socket 31 in each instance will not only receive the web margins 22a but provide with those margins multi-layer rugged pull flanges for the associated bag for pulling the zipper 24 open when desired. This is an especially desirable structure where the bag wall web is of a material such as polyproplyene or the like of very thin section which might in and of itself be of insufficient form retention to provide satisfactory pull flanges. Such a condition may be encountered where it is desired to have the bag body web of 7~
1 a thin plastic such as polyproplyene, while the zipper strips 25 and 27 are extruded from polyethylene.
These materials are relatively fusibly incompatible, at least in a practical sense in the plastic bag art.
While the zipper flanges 30 may be adhesively secured to the bag wall web margins, such securement presents problems as has been previously discussed. According to the present invention, all of the advantages of bags provided with pull flanges, and in particular multi-layer pull flanges is attained by providing the web margins 22a with perforations 32 at suitable intervals along the length of the margins received within the sockets 31, and heat sealing the turned flanges 30 to themselves through the perforations 32 as shown at 33. This provides solid connecting anchors at 33 which permanently secure the zipper strips to the bag wall - web. By having the apetures 32 elongated in the direction of the length of the zipper strips, the anchors 33 can be likewise elongated in that direction. Thereby, advantageous shear strength is provided for resisting outward pulling forces applied to the web margins 22a within the multi-layer Pull flanges when manipulating the same for pulling the zipper 24 open. It-will be observed that the zipper profiles 28, 29 are located substantially below the upper ends of the pull flanges, so that ample width of the pull flanges extends upwardly, that is toward the top end, of ; the bag to facilitate grasping of the pull flanges when ; desired.
For reclosing the zipper after it has been opened, it is merely necessary to apply pressure to the profile areas of the zipper strips through the bag walls 21 and thereby press the zipper profiles into interlocking relation. As is known, with this kind of zipper in which the zipper strips 1 are extruded plastic members, the profiles are resiliently flexibly enterengagable and separable. By having the zipper strips 25 and 27 unattached to the bag walls 21, except at the anchors 33, the bag walls 21 are adapted to expand away from the closed zipper 24 under the influence of normal internal pressures, so that the zipper will not be pulled open by reason of those internal pressures.
However, if it is desirable for the bag to resist over and above normal internal opening pressures, the zipper section 25 is provided with a flange 30 on the otherside of the zipper profiles which extends in a direction opposite to that of flange 30 before said flange was bent over and with a continuation of the bent over zipper flange 30. In addition the web margins are provided with a second set of perforations 32b so that the flange 30 can be heat sealed to the continuation of the folded zipper flange 30 through said perforations 32b at the same time that the zipper flange 30 is sealed to itself through the perfor-ations 32.
If it is desired to provide the zipper 24 with pilferproof means, that is with a means that will retain the bag 20 closed until it is legitimately opened, the arrangement depicted in FIGS. 2 and 3 may be employed.
Here the various components may be substantially the same as in the structure of FIG. 1 except for the pilferproof feature, and therefore without going into a repetition of - the description, identical reference numerals in FIGS. 2 and 3 will be understood to relate to the same description of the identically enumerated elements of FIG. 1. In FIGS. 2 and 3, the lateral flange extension 30 are formed longer than the flange extensions 30 in FIG. 1 so that upon 1 doubling the flange extensions 30 upon themselves for the same purpose and to the same effect as in FIG. 1, fold projections 30a are formed which extend substantially beyond the edges of the bag wall margins 22. Then, by fuibly sealing the folds 30a together, a pilferproof top seal 34 is produced. The pilferproof seal may either extend continuously along the length of the zipper 24, or may take the form of spot seals 34a at desirable intervals along the zipper length. In either event, in order to open the bag, it will be necessary to snip off or rip open the pilferproof seal, or tear it along a line of weakened tear resistance.
While the constructions shown in FIGS. 1-4 do not provide a complete barrier bag, that is, a bag which is thoroughly sealed against leakage of fluid, vapor or gas, where that is a consideration, the bag construction 35 disclosed in FIG. 5-15 meets that requirement. In the bag 35, thin bag wall web 37 is folded upon itself to provide - a closed bottom 38 and an openable top 39 reclosable by means of a zipper 40. In this instance, the zipper 40 comprises a zipper strip 41 which is complementary to a zipper strip 42, both of the zipper strips comprising extruded plastic sections having interlockable complementary transversely hook shaped profiles 43 and corresponding grooves 44. Each of the zipper strips 41 and 42 has a return bent base flange 45 directed toward the outer end of the bag and providing an outwardly opening longitudinally extending slot-like socket groove 47. Within the socket groove 47, in each instance, is received in a tucked in fashion a double folded web 48 of the outer marginal portion of the associated bag body wall 37. From each of the tucked in fold webs 48, a pull flange terminal extension 4 ~- projects outwardly.

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1 Fixed, anchored attachment of the bag wall fold flanges 48 within the socket grooves 47 is effected by fused connecting anchors extending to and between the zipper strips through holes 51 formed in the fold web 48 at suit-able intervals along their length. That is, the anchors 50 are formed by fusing the zipper flanges 45 through the openings 51 to the opposed zipper strip body bases.
Then, to provide complete barrier sealing of the bag 35, not only are the opposite sides of the bag cross-sealed as shown at 52, but the outer edge portions of the pull flanges 49 are sealed together as shown at 53. While the zipper 40 and the bag body material may not be fusibly compatible, the zipper strips 41 and 42 are fusibly compatible with one another, and the material of the bag walls 37 is fusibly compatible with itself, so that the seals 52 and 53 thoroughly seal the sides and top of the bag while the bottom of the bag is, of course, thoroughly sealed by being simply the fold 38. In this fashion the zipper, which may not be impervious to gas or vapor has been completely encompassed by the bag body walls. In addition, of course, the top seal 53 serves as a pilferproof structure.
- A series of steps in a method of making the bag 35 are exemplified in FIGS. 6-15. A continuous web of bag body film B (FIG. 6) is advanced step-by-step through the forming process, being first folded over along its side ~; margins as shown in FIG. 7 to provide the folds 48. Then ~ (FIG. 8), the folds 48 are punched to provide the series of `~! spaced anchor holes 51 which, as shown are longitudinal elongated. Thereafter (FIG. 9), the zipper strips 41 and 42, as supplied in continuous strip form, are assembled so ~" '`
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1 that the folds 48 are received within the groove sockets 47, then the anchors 50 fused through the openings 51 (FIG. 10) to anchor the bag body material and the zipper strips to one another.
The assembly of bag body material 37 and zipper strips 41, 42 is then ready to be manipulated from the laid out or transversely flat production arrangement into the folded up bag formation as depicted in FIGS. 11-13. This may be effected, as shown, by swinging the side to which the zipper 42 is attached into complementary position relative to the side to which the zipper 41 is attached as indicated by the dashed arrow 54 in FIG. 11. Thereby, the bag wall 37 attached to the zipper strip 41 is pulled back over this zipper strip leaving the associated pull flange 49 projecting away from the zipper strip 41, as shown in FIG. 12. Then the zipper strip 42 is turned about its axis from the position shown in FIG. 12 into the position shown in FIG. 13 into complementary opposition to the zipper strip 41 as also shown in FIG. 13. This turns the pull flange 49 attached to the zipper strip 42 outwardly into ` opposing relation to the pull flange attached to the zipper strip 41, again as shown in FIG. 13. Thereafter, the zipper strips 41 and 42 may be interlocked to close the zipper 40 (FIG. 14) and the up to this point continuous ribbon of bag material may then be cross-sealed at successive bag section ` intervals by means of the cross seals 52.
Generally, when reaching the stage in manufacture as depicted in FIG. 14, the series of bags 35 will be either stored for future use, or sent on directly to a filling ; 30 station where the ribbon of bag sections will be located sequentially under a bag filling device such as a nozzle, :: -10-:

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1 the zipper 40 opened, the bag filled, and the zipper closed. Then (FIG. 15) the top seal 53 may be completed along the upper end portions of the pull flanges 49. At this time, also, the respective filled bags 35 may be separated from one another by severing along or otherwise separating the side seals 52, by which the bag sections up to that time have been connected together. Alternately the continu~us ribbon of bag material may be sent to a form fill and seal machine, where the bag manufacture and filling of same are carried out in a series of sequential operations.
For some purposes, it may be undesirable, or at least more convenient, to provide bags 55 (FIG 16) with a zipper 57 located on the outside of the bag instead of on the inside of the bag, but nevertheless providing the general advantages of the bags 20 and 35, and more particularly the latter which provides a bag which is not only pilferproof, but also provides a secure barrier for the contents. To this end, the bag 55 has a folded web body providing side - 20 walls 58 folded to provide a bottom fold 59. A top opening 60 is flanked by pull flanges 61, extending to a desirable width above the location of the zipper 57. Since secure barrier film for the bag body is generally of a material such as polyproplyene which is fusibly incompatible with the usual materials such as polyethylene from which the zipper 57 is preferably extruded, the arrangement in the , -` bag 55 is such that similarly to the bags 20 and 35, the zipper 57 is attached to the bag body by means of fused anchors. To this end, the zipper 57 comprises an extruded zipper strip 62 having a generally arrow shaped cross section male profile rib 63 adapted to snap into retaining ' ~ , ' 7~3()~

1 enterengagment in a complementary grooved profile 64 carried by a zipper strip 65. In this arrangement, the bag body walls 58 are pinched together and an area 66 of the pinched walls forced into the interlocked profiles of the zipper 57, substantially as shown. It will be understood, of course, that the resilient stiffness of the complementary zipper profiles 63 and 64, and the thinness of the bag walls 58 will conveniently permit such pinching and interlocking of the bag wall material 66 in the zipper along the inner sides of the pull flanges 61, by simply squeezing the zippers profiles 62 and 65 toward one another. In addition the integrity of the bag wall barrier film has not been affected since the zipper is attached to the bag wall film outside of the seals enclosing the bag contents.
For attaching the zipper 57 to the bag 55, the - opposite ends of the zipper strips 62 and 64 are anchored together at each side of the bag by means of a respective fused anchor 67 extending through an anchor hole 68 in a fused cross seal 69 running along the respective side of the bag. Thus, although the zipper strips 62 and 65 are not attached to the bag walls 58 except by means of the ~- anchors 67 in the side seals 69, there is a secure connected relation of the zipper to the bag. Further, by having the zipper strips 62 and 65 equipped with respective upwardly projecting base flanges 70 and coplanar downwardly projecting base flanges 71, thereis adequate vertical (considered with the bag with its top end extending upwardly) resistence to relative deformation of the zipper strips when the zipper is open, so that when it is desired to close the bag, the profiles 63 and 64 of the zipper will be conveniently aligned to be forced together manually for lockingly closing .

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1 the top of the bag. When it is desired toOpen the bag, the pull flanges 61 and the upper zipper strip base flanges 70 are pulled apart to unsnap the zipper.
Although for some purposes, the sealed relation attained across the top of the bag by the pinching of the bag wall material 66 within the closed zipper 57, there may be occasions where a more thorough seal is desired. In such event, the pull flanges 61 may be sealed together along their top edge portions as indicated at 72, in similar fashion as the bags 35 are sealed at 53. Such pinch flange seals not only serve as barrier seals but also as pilfer-proof seals. When it is desired to open the bag, these seals may be snipped off or ripped off or otherwise opened for access into the bag which may be reclosed by means of the zipper carried by the bag.
FIGS. 18 and 19 demonstrate steps in applying the zipper strips 62 and 65 to the bag 55. This may be done in a continuous assembly method, wherein the bodies of the bag 55 are formed up from the desired film web and the side seams or seals 69 are formed connecting the bags in a ribbon , series. The anchor holes 68 are formed in the side seals for each bag section, and the zipper strips 62 and 65 are brought into assembly with the bag section ribbon sub-stantially as shown in FIG. 18. Then, the zipper strips are .
brought together in alignment on opposite faces of the bag ribbon aligned with the anchor holes 68. By means of ` suitable heat sealing, ultrasonic head and anvil means, or the like schematically identified at 73, the portions of the zipper strips 62 and 64 which sandwich the bag side seals 69 therebetween are fused together into the configur-ation represented in FIG. 17 whereby the attachment anchors 67 are formed to extend through the anchor holes 68.

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~.~7~ 8 1 Thereafter, the bags may be filled and sealed across thetops of the pull flanges 61 and the respective bags separated from one another along median separation lines 74 separating the two halves of each of the side seals 69 in each instance as represented in FIG. 19. Alternately, all the abo~e steps may be combined in a form fill and seal machine.
It will be understood that variations and modifi-cations may be effected without departing from the spirit and scope of the novel concepts of the present invention.

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Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a bag having a thin web material body with an openable top flanked by opposed upwardly projecting margins and an extruded plastic zipper means carried by and along said margins, and wherein: said bag body and said zipper means are fusibly incompatible; said zipper means comprising a pair of strips having complementary separably interlocjable zipper profiles located sub-stantially below upper ends of said margins; holes in the material of said bag body; and fused connecting anchors extending from said zipper strips through said holes and permanently attaching said zipper strips to said bag body.

2. A bag according to claim 1, wherein said zipper strips have respective base groove sockets, and portions of the material of said bag body having said holes is received in said sockets, and said anchors extend across said groove sockets and through said holes in the portions of the bag body within the sockets.

3. A bag according to claim 2, wherein said sockets are provided by return bent pull flanges on said zipper strips, and said portions of the bag body within said sockets comprise said margins on bag body.

4. A bag according to claim 3, wherein said return bent pull flanges on said zipper strips extend beyond said margins within said sockets, and pilfer proof sealing means connecting said zipper pull flanges.

5. A bag according to claim 3, wherein one of said zipper strips has a flange therealong extending inwardly from the zipper profiles thereon, the portion of the return bent pull flange of said one zipper strip which is on the outer side of the associated body margin extending into overlapping relation to said zipper strip flange, and said overlapping return bent flange portion being attached to said zipper strip flange by means of fused connecting anchors extending through additional holes in said associated body margin.

6. A bag according to claim 2, wherein said base groove sockets open toward the open end of the bag, and said portions of the bag body material comprise fold webs in the bag body at the inner sides of pull flanges provided by said margins of the bag body, and said fold flanges having said holes.

7. A bag according to claim 6, wherein said pull flanges of the bag body have pilferproof sealing means therealong.

8. A bag according to claim 2, wherein said base groove sockets open towards the open end of the bag and wherein a part of the upper bag body is folded within said sockets and contains said holes, and a part extends out beyond said socket to act as a pull flange.

9. A bag according to claim 1, wherein said zipper means are located on the inside of the bag.

10. A bag according to claim 1, wherein said zipper means are located on the outside of the bag.

11. A bag according to claim 10, wherein said holes are in side seals of the bag, and ends of said zipper strips being connected together by said anchors extending through said holes in said side seals.

12. A bag according to claim 1, 2 or 3, wherein said holes are elongated lengthwise of said pull flanges.

13. In a bag having a thin web material body with an openable top flanked by opposed upwardly projecting margins and an extruded plastic zipper means carried by said body along said margins, and wherein:
said zipper means comprise a pair of strips having complementary separably interlockable zipper profiles below the upper ends of said margins; one of said zipper strips being located along the outside of one side of the bag body and the other of said zipper strips being located along the outside of the opposite side of said bag body, and the zipper strips being aligned so that their profiles are in matching relation; said material of said bag body and said zipper strips being fusibly incompatible; said bag body having portions thereof near said zipper strips provided with holes therethrough; and fused anchors extending into said holes and securing the zipper strips to said bag body.

14. A bag according to claim 13, wherein said zipper strips have base flanges serving to cooperate with said margins for effecting separation of said profiles by pulling said margins and base flanges apart.

15. A bag according to claim 13, wherein said bag body has side seal seams with said holes therethrough; and said fused anchors securing the ends of said zipper strips together through said holes, so that the zipper profile strips are attached to said bag body without affecting the integrity of the side seal seams enclosing the contents of the bag.

16. A bag according to claim 1, wherein an inwardly tucked fold extends entirely across the upper end portion of a wall panel of said bag body and includes a pull flange which has said holes and comprises an upward extension of the entire width of said fold, and one of said fastener strips extends entirely across the inner end portion of said pull flange and is secured thereto by said anchors and faces in bag top closing relation toward the complementary fastener strip on a wall of the bag body opposite said one wall panel.

17. A bag structure according to claim 16, wherein said opposite wall panel also has an inwardly tucked fold on the upper end portion thereof, the pull flange of said other wall panel comprising an upward extension of said other wall panel fold, and said complementary zipper strip being on the inner end portion of said pull flange of said other wall panel and being complementary to and facing toward and engageable closingly with said zipper strip on the inner end portion of said pull flange of said one wall panel.

18. A bag according to claim 1, wherein said fastener strips have upwardly opened sockets therein, and pull flange members secured in said sockets and projecting upwardly therefrom.

19. A bag according to claim 18, wherein said fastener strips are located on inner sides of wall panels of said bag body and have complementary interlockable profiles projecting in interlockable relation toward one another.

20. A method of making a bag equipped with extruded plastic reclosable zipper means, comprising:
forming a bag body from thin web material and having an openable top flanged by opposed upwardly projecting margins; providing extruded plastic zipper strips fusibly incompatible with the material of said bag body and comprising a pair of opposed strips having complementary separably interlockable zipper profiles;
assembling said profile strips along said margins and with the profiles located substantially below upper ends of said margins; and permanently attaching said zipper strips to said bag body by fusibly connecting anchors from said zipper strips through holes in said bag body.

21. A method according to claim 20, which comprises providing said zipper strips with respective base groove sockets, receiving portions of the material of the bag body in said sockets, and extending said anchors across said groove sockets through said holes in the portions of the bag body within the groove sockets.

22. A method according to claim 21, which comprises having said base groove sockets opening toward the open end of the bag, and folding bag body material into webs to provide said portions of the material having the holes and receiving the fold webs in said groove sockets, and extending said upper end margins as pull flanges upwardly beyond said fold flanges.
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23. A method according to claim 22, which comprises sealing said pull flanges for pilferproofing.

24. A method according to claim 20, which comprises providing return bent pull flanges on said zipper strips and thereby forming groove sockets, and receiving said margins in said groove sockets said margins having said holes.

25. A method according to claim 24, which comprises extending said return bent pull flanges on said zipper strips beyond said ends within said groove sockets, and forming pilferproof sealing means connecting said pull flanges.

26. A method according to claim 20, which.
comprises locating said zipper means on the inside of the bag.

27. A method according to claim 20, 24 or 26, which comprises elongating said holes lengthwise of said margins and correspondingly elongating the cross-section of said anchors.

28. A method according to claim 20, which comprises locating said zipper means on the outside of the bag.

29. A method according to claim 28, which comprises forming said holes in side seals of the bag, and connecting ends of the zipper strips by anchors extending through said holes in said side seals.

30. A method according to claim 28 or 29, which comprises pinching material of the body releasibly sealingly between said zipper profiles.