AU2004201271B2

AU2004201271B2 - Bag Incorporating a Handle And Method For Forming Same

Info

Publication number: AU2004201271B2
Application number: AU2004201271A
Authority: AU
Inventors: Barry Mulder
Original assignee: Sealed Air New Zealand Ltd
Current assignee: Sealed Air New Zealand Ltd
Priority date: 2003-03-28
Filing date: 2004-03-29
Publication date: 2010-06-17
Anticipated expiration: 2024-03-29
Also published as: NZ525020A; AU2004201271A1

Description

1 Regulation 3.2 AUSTRALIA PATENTS ACT, 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT ORIGINAL Name of Applicant: SEALED AIR (NZ) LIMITED Actual Inventor: BARRY MULDER Address for service A J PARK., level 11, 60 Marcus Clarke Street. Canberra ACT in Australia: 2601, Australia Invention Title: Bag Incorporating A Handle And Method For Forming Same The following statement is a fWH description of this invention, including the best method of perfoxming it known to us.

2 FIELD OF THE INVENTION The invention comprises a package handle or package incorporating same which will typically be a bag formed from a plastics material which includes a header part formed when the package is sealed closed, and a method for forming same. BACKGROUND It is known to form a header flap or part when sealing a plastics package or bag closed, and then to knife-cut an aperture in the header part, through which a persons fingers can be inserted to carry the package or bag so that the header part and aperture form a carry handle for the bag or package. It is known to so form a carry handle in bags made on form fill and seal machines, which convert roll stock film into bags and fill them with product in one operation. SUMMARY OF INVENTION In broad terms in one aspect the invention comprises a method for forming a handle in a package or bag formed of a plastics material which includes forming or providing a header part at one end or side of the package or bag and forming a handle from the header part which includes a handle aperture and an adjacent portion which depends away from the header part to one side of the header flap. In broad terms in another aspect the invention comprises a package or bag formed of a plastics material which includes a header part at one end or side of the package or bag and a handle formed from the header part which includes an aperture and an adjacent portion which depends away from the header part to one side of the header. Preferably the handle is formed from the header part by thermoforming the header part, or alternatively vacuum or pressure forming the header part or by a combination of thermoforming, vacuum forming and/or pressure forming.

3 Preferably the handle portion extends away from the handle aperture from around the periphery of the handle aperture. BRIEF DESCRIPTION OF THE DRAWINGS The invention is further described with reference to the accompanying drawings, by way of example and without intending to be limiting, wherein: Figure 1 shows a prior art bag including a header part with a handle aperture therein, Figure 2 shows the upper portion including a header part of a bag of the invention and formed by the method of the invention, from one side, Figure 3 shows the upper portion including a header part of a bag of the invention and formed by the method of the invention, from the other side, Figure 4 shows the upper portion of the bag of Figure 2 in side profile, Figure 5 is a close up schematic view of the handle portion of a bag of the invention showing how a users fingers may insert into the handle portion for carrying the bag, Figure 6 is a schematic cross-section view through apparatus for thermoforming the handle portion in bags in accordance with the invention, and Figure 7 shows application of the invention to another form of package. DETAILED DESCRIPTION OF PREFERRED FORM Referring to Figure 1, bags formed of a plastics material incorporating a header flap 1 which is formed typically by heat sealing together (or otherwise bonding) an end (or 4 side) of the bag, have knife-cut therein a handle aperture 2 which enables a users fingers to be inserted through the handle aperture 2 to carry the bag. Referring to Figures 2, 3 and 4, a bag of the invention includes a portion 3 thermoformed from the plastics material of the header flap 1, which depends away from the header flap 1 to one side of the header flap 1, around handle aperture 2. Preferably the portion 3 is formed without puncturing the plastics material of the header flap 1, In an alternative form however possibly small apertures may be formed in the portion 3 without adversely affecting the integrity and strength of the handle. Referring to Figure 6, in manufacture of bags on a form fill and seal machine for example which converts roll stock film into bags and fills them with product in a single operation, the handle portion is thermoformed at approximately the same time as the header flap is heat sealed to close the bag. In Figure 6 reference numerals 5a and 5b indicate heat seal jaws which close against the open end of bag BI in the direction of arrow A to form a header flap to close the bag, by heat sealing the wall sections of the bag together on either side of the top of the bag. Simultaneously a thermoforming plug 6 movably associated with header sealing jaw Sa on one side moves forward transversely in the direction of arrow C into cavity 7 in header sealing jaw Sb on the other side, to form the handle portion in the top of the bag. At the same time knife 8 moves to sever the bag BI from the next bag B2, the bottom seal of which is formed by bottom heat seal jaws 9a and 9b. The heat seal jaws 5a and 5b. thermoforming plug 6, and knife 8 may be driven pneumatically for example. Figure 5 shows how the fingers of a person carrying a bag of the invention may insert into the handle portion formed as described. In use the outwardly extending plastic handle portion 3 may deform under the load of the bag contents, from the shape shown in side profile in Figure 4 to that shown in Figure 5. While in the preferred form described above the portion 3 is fonned from the plastics material of the header flap 1 by thermoforming, in an alternative arrangement the handle portion could be formed by vacuun forming the handle portion 3 in the header part 1 5 from one side or pressure forming the handle portion 3 in the header part 1, with air pressure for example, or by a combination of thermoforming, vacuum forming, and pressure forming. The method of the invention may be used to form handles in bags which are first sealed at one end, filled with product, and then sealed at the other end with a header flap in which the handle portion is formed, but is not limited to such applications specifically. For example such handle portions may be formed in flaps formed at the side of a package which is formed by wrapping around a product or products for example. In another arrangement the handle portion may be first formed in a separate header part or equivalent which is then subsequently heat sealed to or within the mouth of a separate bag at closing of the bag or wrapping of a package. A benefit of the invention is that it may enable bags for example to be formed of a lighter weight film than would otherwise be the case. For example it is conunonly the case that prior art bags of the typo shown in Figure 1 must be formed from a heavier weight film than is required to adequately contain and support the contents of the bag, so that the header flap is sufficiently strong to act as a handle when a handle aperture is cut through the header flap as shown in Figure 1. It is believed that the bags of the invention incorporating such a handle may not necessarily need to be formed of film of any heavier weight than required simply to contain and support the contents of the bag, so that for a given application a lighter weight film may be utilisod, providing economies. Figure 7 shows application of the invention to another form of package namely a package one part of which is formed to a thermoforming or vacuum or pressure forming. Referring to Figure 7 product C such as a cheese block for example, is contained within a package consisting of a thermofonmed vacuum formed or pressure formed lower part 10 and a film layer 11 laminated or heat sealed thereto around the upper periphery of an open cavity in the lower part 10. In forming such a package, conventionally heavier weight film is thermoformed or vacuum formed or pressure formed to provide a cavity in the film, into which the product is then placed (or 6 alternatively package part 10 may be formed around the product and another application). Then a film layer 11, which is usually a lighter weight film, is laminated over the top of the package pat 10, and open cavity thereof, to close the package. In accordance with the invention when the cavity is formed in the package part 10 at the same time portion 3 is formed into the plastics material of header flap 1 which is pmvided, as before, to provide a carry handle for the package. Then when the film layer 11 is sealed in place to close the package, an aperture may be knife-cut through the film 11 above the thermoformed handle portion 3 or alternatively a die part may heat and push the portion of the film layer 11 which extends over the thermoformed portion 3 into the thermoformed portion 3. In an alternative arrangement the package may first be closed by sealing the film layer 11 to the lower package part 10 without first firming the handle portion 3 in the lower package part 10, and then the handle recess 3 may be formed (by thermoforming or vacuum forming or pressure forming) the header part I which consists of both the film of the lower package part 10 and film layer 11 laminated together. The foregoing describes the invention including a preferred form thereof. Alterations and modifications as will be obvious to those skilled in the art are intended to be incorporated within the scope hereof as defined in the following claims.

Claims

1. A method for forming a handle in a package or bag formed of a plastics film material which includes forming or providing a header part at one end or side of the package or bag and forming a handle from the header part which includes a handle aperture and an adjacent portion which depends away from the header part to one side of the header part.

2. A method according to claim 1 including forming the header part as a header flap by heat sealing together two sides of the package or bag at one end or side of the package or bag.

3. A method according to claim 2 including thermoforming the handle from the header part of the package or bag.

4. A method according to claim 3 including thermoforming the handle at approximately the same time as said heat sealing to form the header flap.

5. A method according to any one of claims 1 to 4 including forming the handle between heat seal jaws which close against an open end of the package or bag from either side to heat seal the two sides of the package or bag together and thermoform the handle.

6. A method according to claim 5 including forming the handle of the bag by causing a thernoforming die member associated with the heat sealing jaws to move transversely through the header part of the package or bag to form the handle.

7, A method according to claim 6 including simultaneously severing the package or bag from another package or bag.

8. A method according to claim 1 including vacuum forming the handle in the header part of the bag. 8

9. A method according to claim 1 including pressure forming the handle in the header part of the bag.

10. A method according to any one of claims 1 to 9 including forming said adjacent portion to extend away from the handle aperture from around the periphery of the handle aperture.

11. A method according to claim 10 including forming said adjacent portion of the handle without puncturing the plastics film material.

12. A method according to any one of claims I to 11 including first filling the package or bag with a product and then forming said header part and said handle when closing the package or bag.

13. A method for forming a handle in a package or bag formed of a plastics material, substantially as herein described with reference to the accompanying drawings.

14. A method for forming a handle in a package or bag formed of a plastics material, substantially as herein described with reference to Figure 6 of the accompanying drawings.

15. A package or bag formed of a plastics film material which includes a header part at one end or side of the package or bag and a handle formed from the header part which includes an aperture and an adjacent portion which depends away from the header part to one side of the header.

16. A package or bag according to claim 15 wherein said adjacent portion extends away from the handle aperture from around the periphery of the handle aperture.

17. A package or bag according to either of claims 15 and 16 wherein the header part is a header flap formed by heat sealing together two sides of the package or bag at one end of the package or bag. 9

18. A package or bag according to any one of claims 15 to 17 wherein said handle has been formed without puncturing the plastics film material.

19. A bag according to any one of claims 15 to 18.

20. A package according to any one of claims 15 to 18 which comprises a first package part including a cavity containing a product within the package, and a plastic film extending over and sealed about the cavity to close the package.

21. A bag formed of a plastics material, substantially as herein described with reference to Figures 1 to 5 of the accompanying drawings.

22. A package formed of a plastics film material, substantially as herein described with reference to Figure 7 of the accompanying drawings.

23, A package or bag formed by the method of any one of claims 1 to 14.