GB2289459A

GB2289459A - A bag including a separate sealed pouch for concealing information

Info

Publication number: GB2289459A
Application number: GB9409670A
Authority: GB
Inventors: Brian Taylor
Original assignee: British Polythene Ltd
Current assignee: British Polythene Ltd
Priority date: 1994-05-14
Filing date: 1994-05-14
Publication date: 1995-11-22
Also published as: GB9409670D0

Abstract

A bag 10, 110 includes a sealed light-obscuring pouch 40, 140 comprising a folded sheet of material attached to the bag. The same seals (30, 32 Figure 1; 130, 132 Figure 3) seal the edges of the bag and pouch and a further transverse seal 24, 124 closes the top. The pouch may be attached to one side wall of the bag or both. Information may be carried inside the pouch, either printed on the pouch itself or on a contained slip. The "light-obscuring" function may be provided by material of low transmission properties eg co-extruded polythene layered material or by overprinting on the outer and/or inner surfaces to mask the printed matter in the pouch. The material of the main bag 12, 112 may be transparent to allow the pouch and the contents of the bag to be seen. <IMAGE>

Description

INNER POUCH BAG The present invention relates to plastic bags and similar packaging, and in particular to such bags with an integral pouch formed therein.

In the promotion and provision of various products and services it is now widespread to provide a card or paper envelope-type pouch which, upon tearing or cutting one or more sides of the pouch enables the recipient of the pouch to reveal the contents of the pouch. The contents of the pouch may be an inserted slip of paper, or information printed on the inside surfaces thereof.

Such pouches have wide application, their principal function being the concealment of the information contained therein. Typical means to achieve this are the provision of overprinted outer and/or inner surfaces which mask any printing on the inside of the pouch when strong light is transmitted through the pouch, by causing a confusing jumble of shapes to be visible. Another way of achieving this is to provide very low light transmission properties of the envelope or pouch.

Examples of use are for pay-slips, credit card PIN number notification envelopes and lottery cards.

It is an object of the present invention to provide a similar pouch arrangement integrally-formed within a plastic bag or similar flexible packaging structure which may be used, for example, in the promotion of certain pre-packaged products in a supermarket.

It is a further object of the present invention to provide a manufacturing process capable of using existing production equipment adapted to form such promotional packaging.

In accordance with one aspect of the present invention there is provided a bag for packaging product, the bag having integrally formed therewith a separate, sealed, light-obscuring pouch.

In accordance with a further aspect of the present invention there is provided a method of manufacturing a bag comprising the steps of: longitudinally overlaying a first flexible sheet with a second flexible sheet; forming a longitudinal fold down both sheets simultaneously; bonding the sheets together to form two lateral seals; and simultaneously closing the pouch formed by the second flexible sheet and one side of the bag by bonding the sheets together to form a transverse seal.

Embodiments of the present invention will now be described by way of example and with reference to the accompanying drawings in which: Figure 1 shows a schematic plan view of a bag in accordance with one embodiment of the present invention; Figure 2 shows a cross-sectional side view through the bag of figure 1, on section A--A; Figure 3 shows a schematic plan view of a bag in accordance with a further embodiment of the present invention; Figure 4 shows a cross-sectional side view through the bag of figure 3, on section B-B; Figure 5 shows a schematic plan view of a bag in accordance with a further embodiment of the present invention; Figure 6 shows a cross-sectional side view through the bag of figure 5, on section C-C;; Figure 7 shows a schematic plan view of a bag in accordance with a further embodiment of the present invention; Figure 8 shows a cross-sectional side view through the bag of figure 7, on section D-D; and Figure 9 shows a schematic side view of the manufacturing process for forming the bag of figures 1 and 2.

With reference to figures 1 and 2 there is shown a presently preferred embodiment of the present invention. A bag 10 is formed from an outer sheet 12 of flexible material, preferably polythene or the like.

The material may be transparent, translucent or opaque, and may be suitable for printing on both outer or inner surfaces using well known techniques. The sheet 12 is folded at the bottom of the bag 10 to form outer fold 16. An inner sheet 20 of flexible material is introduced between the folded outer sheet 12, also folded at its lower edge to form an inner fold 22 approximately coincident with the outer fold 16. (It will be understood that the separation of the sheets in the cross-sectional figures has been greatly exaggerated in the interests of clarity of illustration.) In accordance~with normal manufacturing processes, the sides of the bag are formed by providing lateral seals 30,32 which run the length of the bag 10.In polythene bag manufacture, this is customarily achieved by use of a hot knife processing, where the various layers of the bag are heat welded together and simultaneously cut. Although the edges 34,36 of the bag are shown marginally separated from the weld or seal lines 30,32, it will be understood that these may in fact be coincident, as shown in analogous figures 5 and 7, for example. Various bonding techniques well known in the art may be used to form the seals 30,32, in accordance with whatever techniques are appropriate to the materials being used for sheets 12 and 20.

A transverse seal 24 is provided to close a pouch formed by the inner sheet 20, and to further bond this pouch to the outer sheet 12. The transverse seal 24 also occludes the inside of the main portion 11 of bag 10, thus ensuring that any articles placed in the bag do not fall below the level of the transverse seal 24. It will thus be apparent that a completely closed pouch 40 is formed which is contained within the outer sheet 12 of the main bag 10. Advantageously, this sheet can be made detachable either by cutting along line 42 with scissors, or by providing perforations along line 42 without affecting the functionality of the bag 10.

It will be noted that throughout the drawings, the bags are shown in open condition. In use, the bags would be filled using known packaging techniques and sealed along top edge 15. Other filling techniques may be used.

Thus for a lottery-type promotion, the winning or non-winning status of the bag 10 may be printed on the inside surfaces of the pouch 40.

Upon purchasing a bag 10, the customer may then sever the pouch and bag along line 42, detaching lower portion 44 of the bag 10, and revealing the inner surfaces of the pouch 40. Complete detachment of the inner sheet 20 from the detached portion 44 of the bag 10 is possible by tearing or severing the seals 30,32 on the detached portion 44.

An important feature of such a bag if it is to be used in lottery-type promotions is the provision of a "light-obscuring" function of the inner sheet 20 and/or outer sheet 12. As described hereinbefore, typical means to achieve this are to provide very low light transmission properties of the envelope or pouch 40, or to provide overprinted outer and/or inner surfaces which mask any printing on the inside of the pouch when strong light is transmitted through the pouch, by causing a confusing jumble of shapes to be visible.

According to a presently preferred embodiment, the inner sheet 20 is formed from a co-extruded film of polythene or similar material. One of the co-extruded layers is a high density black material to provide the light obscuring properties, and the other co-extruded layer is white or a light colour to provide a light reflecting surface to the outer surface of the bag. Preferably, the white layer forms the outer surface of the pouch and the black layer forms the inner surface of the pouch, and is over-printed with a message as to whether the recipient of the bag has either won, or not won, a lottery prize. In the case of a transparent plastic bag 10, the outer sheet 12 will enable the white, outer surface of the inner sheet 20 to be visible and this can be over-printed with suitable promotional literature.

Alternatively, the promotional literature can be overprinted on the outer surface of the bag 10 on the lower portion 44.

In a further preferred embodiment, the co-extruded sheet includes a third, intermediate layer between the dark and the light layers. In a presently preferred embodiment, the co-extruded sheet has a minimum opacity to visible light of greater than 95% or a visible light transmission coefficient of less than 5%.

As an alternative to the bag 10 comprising two separate sheets 12,20, use of a single sheet 12 with suitable light-obscuring properties could effect the formation of a pouch 40 detachable from the main portion 11 of the bag 10.

It will be understood that the pouch 40 could alternatively contain a separate sheet of paper or fabric or the like to carry concealed information within the pouch.

With reference to figures 3 to 8, exemplary variations of the construction of bag are described. In figures 3 and 4, a bag 110 is formed in which the pouch 140 comprises a folded inner sheet 120 which is bonded to the inside of the outer sheet 112 by two transverse seals 124, 125, and also by lateral seals 130,132.

The bag 210 of figures 5 and 6 is similar to that of figures 3 and 4, but uses only a single transverse seal 224, and two lateral seals 230,232 to form pouch 240. The lower edge of the pouch is sealed by virtue of being formed by a folded inner sheet 220 having fold 216.

The bag 310 of figures 7 and 8 is similar to that described with reference to figures 1 and 2, but the sheet 320 used to form the pouch 340 is folded outside of the sheet 312 used to form the bag 310. The pouch 340 is bonded to the main sheet 312 of the bag 310 by a single transverse seal 324, and two lateral seals 330, 332.

With reference to figure 9 there is described a convenient method for manufacture of the bag 10 according to figures 1 and 2. The outer sheet 12 of the bag is provided from a sheet 412 fed from a roll 400. The inner sheet 20 of the bag is provided from a sheet 420 fed from a roll 402. The sheets 412,420 are overlaid by passage between two guide rollers 404,406 and a folding frame 408 bears down on a longitudinal centre line of both sheets. Parallel to the plane of the folding frame are two guide rollers 460,461 between which pass sheets 412,420, which cause the sheets 412 and 420 to be folded about the lower edge 409 (shown in outline) of the folding frame 408 thus providing the necessary folded and overlaid sheets 412,420 to the right of the rollers 460,461.

Sheet 420 is folded within sheet 412 and is thus shown in outline only.

The transverse seal 24 of bag 10 is made by a hot roller shown schematically at 424, and intermittently along the sheets 412, 420 a hot knife 430 provides lateral seals 30,32 and also severs the sheeting to form the individual bags 10.

It will be understood that similar equipment can readily be adapted to form the bags of the other embodiments described herein by appropriate feeding of sheets 420,412 to transverse seal hot rollers positioned either before or after the folding process.

Claims

1. A bag for packaging product, the bag having integrally formed therewith a separate, sealed, light-obscuring pouch.

2. A bag according to claim 1 wherein the pouch is formed adjacent to an inner wall of the bag.

3. A bag according to claim 2 wherein the pouch is formed between two inner walls of the bag.

4. A bag according to claim 3 wherein the pouch occludes one end of the interior of the bag.

5. A bag according to any preceding claim wherein the pouch and bag are formed from a flexible material, the pouch being sealed within the bag by at least two lateral seals of the bag.

6. A bag according to claim 5 wherein the pouch is attached to one wall of the bag by a further two transverse seals.

7. A bag according to claim 5 wherein the pouch is attached to two walls of the bag by a single transverse seal.

8. A bag according to claim 7 wherein the bag is formed from a single sheet of plastics material having a first fold therein to form one side of the bag, and at least two lateral seals to form two other sides of the bag, and wherein the pouch is formed by a second sheet of plastics material folded adjacent to said first fold and sealed on two sides by said lateral seals, and on a fourth side by a transverse seal.

9. A bag according to claim 8 wherein the transverse seal defines one end of an internal cavity of the bag.

10. A bag according to any one of claims 5 to 9 wherein the pouch is formed from a co-extruded polythene material comprising two films, a first film having a minimum opacity to visible light of greater than 90%.

11. A bag according to any preceding claim having printed matter on the inside walls of the pouch.

12. A bag for packaging product, the bag having an integrally formed pouch adapted to visibly conceal information contained therein until the pouch is cut or torn open.

13. A method of manufacturing a bag comprising the steps of: longitudinally overlaying a first flexible sheet with a second flexible sheet; forming a longitudinal fold along both sheets simultaneously; bonding the sheets together to form two lateral seals; and simultaneously closing the pouch formed by the second flexible sheet and one side of the bag by bonding the sheets together to form a transverse seal.

14. A method according to claim 13 further including the steps of printing information-on-one surface of the second sheet prior to forming the bag, the second sheet being oriented such that said surface forms the inside surface of the pouch.

15. A method of manufacturing a bag comprising the steps of: longitudinally overlaying a first flexible sheet with a second flexible sheet; forming a first longitudinal fold along the second sheet; bonding the two layers of the second sheet together with one layer of the first sheets together to form a transverse seal; forming a second longitudinal fold along the first sheet to enclose the second sheet; and closing the pouch formed by the second sheet and closing the sides of the bag by forming two lateral seals.