NZ264733A - Bag openable from either end: one end temporarily closed by strip of adhesive tape when bag is filled - Google Patents

Description

264733 Patents Form No. 5 OurRef: AA800635 Complete After Provisional Application No. 264733 Filed: 19 October 1994 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION A METHOD OF MANUFACTURING OPEN ENDED BAGS We, MAINGUARD PACKAGING LIMITED, a New Zealand company of 66 Carmen Road, Hornby, Christchurch, New Zealand hereby declare the invention, for which We pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement: PT0532488 N..?\ PATENT OifTlCE 19 OCf 13S5 264733 The invention relates to bags and particularly to bags the contents of which are accessible from both ends of the bag.

Bread has in the past been packaged in waxed or greaseproof paper packaging which allows a consumer access to either end of the loaf. This can be useful, for example, with different cuts of bread or even different breads.

Recent use of gusseted plastic bags has meant that only one end of a loaf is accessible.

There is therefore a need for a bag accessible from both ends, which enables different product to be obtained from each end of the bag.

An object of the invention is to provide a bag and its method of construction which allows access to both ends of the bag.

A further object of the invention is to provide a bag which offers a useful alternative choice to conventional bags.

According to the first aspect of the invention there is provided a bag capable of being opened from both a first and a second end, the first end of the bag being temporarily closed to form a false bottom by means of a transverse strip of appropriate tape and/or adhesive, the false bottom enabling the bag to be used in conventional packaging machinery before tie means are used on at least one open end of the bag to close the bag.

Preferably tie means can used at both ends of the bag with one of the tie means gathering the bag adjacent or over the transverse strip.

The temporary closure of the first end of the bag can additionally include formation at the first end of a transverse weld or fold which forms a closed end which is removable by providing transverse perforations which allow the closed end to be torn off to open this end of the bag.

The transverse strip of tape/adhesive can be a strip of double sided adhesive tape applied across the bag during manufacture. The tape/adhesive can be applied at a point spaced from the first end of the bag.

According to a second aspect of the invention there is provided a method of constructing a bag including the steps of: - applying a strip of tape and/or adhesive to a film of material from which a bag is to be made; - folding the film of material, so as to form an upper web and a lower web;and - cutting the film to form an opening at one end of the bag which is closed.

According to a third aspect, there is provided a method of constructing a bag including the steps of: - applying a strip of tape and/or adhesive to a film of material from which a bag is to be made; - folding the film of material, so as to form an upper web and a lower web; - forming a transverse weld or fold at one end of the bag; and - forming adjacent the transverse weld or fold a line of perforations which form a closed end which is removable from the bag by being torn off. 264733 Further aspects of the invention will become apparent from the following description which is given by way of example with reference to the accompanying drawings in which: Figure 1 shows a plan view of an example of bag according to the present invention; Figure 2 shows a view from below of the bag shown in Figure 1; Figure 3 shows an end view of the bag shown in Figures 1 and 2; Figure 4 shows a sectional view from the side of the bag shown in Figure 3; Figure 5 shows a sectional view through the bag shown in Figure 4; Figure 6 shows a view of a packaged product in the bag shown in Figure 1 to 5; Figure 7 shows an end view of the packaged product shown in Figure 6; Figure 8 shows a diagrammatic schematic view of an example of packaging machinery that can be used to form a bag according to the present invention; Figure 9 shows a side view of part of the packaging machinery shown in Figure 8; Figure 10 shows a view in the direction of arrow A (Figure 9) of part of the packaging machinery shown in Figure 9; and Figure 11 shows a plan view of an alternative example of bag according to the invention.

The examples of the present invention will be described with reference to a plastics film bag for use in packaging bread. It is to be appreciated that with minor modifications the technology can be adapted for use with other food or packaged products and that if required the bag can be formed from different materials. 264733 In the first example shown in Figures 1 to 5 is a plastics bag generally indicated by arrow 1 formed in modified bag manufacturing machinery. A schematic example of suitable bag manufacturing machinery is shown in Figures 8 to 10.

In this case the bag 1 is formed from a web of film which can be printed on one face. The film is unwound from a roll 16 and progresses through a weed compensator assembly 17. The inside surface of the bag where the strip Of tape 4 will be located, is then treated by a Corona treatment assembly 18. A strip 4 of food grade resealable adhesive tape is applied to a portion of the surface of the web, the portion forming the upper web 2 when the web is folded. The adhesive tape joins the two webs 2 and 3 together once folded together. The adhesive tape may be a double sided tape and the bag machine is modified to include a double sided tape unwind and guide assembly 11.

The web is folded by means of a standard Vee folder 10 to form, as shown in the Figures 1 to 5, an upper web 2 and lower web 3. The part of the bag on which printing is available is shown shaded in Figures 1 and 2.

The bag manufacturing machine is further modified to cut the web with a knife 12 to form an openable end 5 opposite to the other opening 6 of the bag 1.

After cutting of the web a release liner of the tape is removed so that webs 2, 3 adhere together. The release liner is removed by means of a folding bar 13 which peels off and turns the release liner away from the adhesive and out of the film. The release liner is then removed by means of a driven pressure roller assembly and a venturi extract system 14. 264733 The webs 2, 3 then progress to a conventional bag machine in the direction of arrow 15.

The other end 6 of the bag has a pair of wickett holes 7 so that the bags when formed on the bag making machinery are stacked in a wickett (not shown). The end 8 of the upper web 2 in the example does not lie completely on top of the lower web 3.

The alternative construction of bag shown in Figure 11 is indicated by arrow 19. In this example similar parts to those shown in Figures 1 to 5 are referenced by the same numerals. The bag 19 in this example is not cut by knife 12 but is perforated along line 20 across the bag 19 and parallel to end 21 of the bag. The perforations are formed in both the top and bottom webs of the bag so that section 22 can be torn from the bag.

As is shown in Figures 6 and 7 the bag 1 can be used to package a loaf of bread. The bag has been designed to operate with minimally modified standard bread bag filling machinery. In this machinery the plastic bag 1 as it is fed through the machine is opened by compressed air. The provision of the false bottom formed by the appropriate tape adhesive 4 allows the end of the bag at 6 to open so that it can be filled by the machinery with a loaf of bread.

In practice the ends of the bag are closed by means such as a kwik™ clip 9 or with a twistie tie at each end as shown. The bag is dimensioned so that the ends can be gathered as shown for the placement of the tie means 9 at each end. It is to be appreciated that in an alternative construction (not shown) that the strip of tape 4 is of sufficient strength to hold the bag end 5 closed without an extra tie means. In this instance more than one strip of tape 4 may be necessary. 264733 The construction of the bag in Figure 11 has the advantage that the bag 19 is filled with the section 22 in place. Only when a consumer needs to access end 21 of the bag is the section 22 removed. This allows access to this end of the bag. In this bag the open end of the bag is closed in the normal way by a twistie tie or a clip.

The advantage of the bag in this form is that the product is readily accessible from either end of the bag without having to break a seal formed at one end. This enables, as stated previously, different thicknesses of sliced bread or different types of bread to be acquired from either end of the bag.

Thus by this invention there is provided a bag and its method of construction which allows access to either end of the bag.

A particular example of the invention has been described and it is envisaged that improvements and modifications can take place without departing from the scope of the description and appended claims. 264733

Claims (17)

WHAT WE CLAIM IS:

1. A bag capable of being opened from both a firs* and a second end, the first end of the bag being temporarily closed to form a false bottom by means of a transverse strip of appropriate tape and/or adhesive, the false bottom enabling the bag to be used in conventional packaging machinery before tie means are used on at least one open end of the bag to close the bag.

2. A bag as claimed in claim 1 wherein the tie means are used at both ends.

3. A bag as claimed in claim 2 wherein tie means close the first end adjacent or over the transverse strip of appropriate tape and/or adhesive.

4. A bag as claimed in any one of the preceding claims wherein the transverse strip is a strip of double sided adhesive tape.

5. A bag as claimed in any one of the preceding claims wherein the transverse strip is applied at a point spaced from the first end of the bag.

6. A bag as claimed in any one of the preceding claims wherein a transverse weld or fold is formed at the temporarily closed first end of the bag, the transverse weld or fold forming a closed end which is removable by providing transverse perforations which allow the closed end to be torn off to open this end of the bag.

7. A bag as claimed in any c ne of the preceding claims capable of being printed on. 264733

8. A bag as claimed in any one of the preceding claims wherein the second end of the bag has a pair of wickett holes.

9. A bag substantially as herein described with reference to the accompanying drawings.

10. A method of constructing a bag including the steps of: - applying a strip of tape and/or adhesive to a film of material from which a bag is to be made; - folding the film of material, so as to form an upper web and a lower web; and - cutting the film to form an opening at one end of the bag which is closed.

11. A method of constructing a bag including the steps of: - applying a strip of tape and/or adhesive to a film of material from which a bag is to be made; - folding the film cr material, so as to form an upper web and a lower web; - forming a transverse weld or fold at one end of the bag; and - forming adjacent the transverse weld or fold a line of perforations which form a closed end which is removable from the bag by being torn off.

12. A method as claimed in either claim 10 or 11 wherein the strip of tape and/or adhesive is applied to the surface of the film which will form the upper web when the film is folded. -10- £,v "T / \J

13. A method as claimed in any one of claims 10 to 12 wherein the tape is double sided adhesive tape.

14. A method as claimed in claim 13 further including the step of: - removing a release liner of the double-sided adhesive tape so as to allow the upper web and the lower web to adhere together.

15. A method as claimed in any one of claims 10 to 14 further including the step of: forming a pair of wickett holes at one end of the bag.

16. A method as claimed in any one of claims 10 to 15 wherein the upper web does not lie completely on top of the lower web.

17. A method of constructing a bag substantially as herein described with reference to the accompanying drawings. MAINGUARD PACKAGING LIMITED By Their Attorneys BALDWIN SON & CAREY c v/holdback/ CSPEC08474 end of claims