CA1060852A

CA1060852A - Flexible wall container

Info

Publication number: CA1060852A
Application number: CA247,009A
Authority: CA
Inventors: Bryan G. Howell; Gordon H. Ringrose
Original assignee: Twinpak Ltd
Current assignee: Twinpak Ltd
Priority date: 1976-03-01
Filing date: 1976-03-01
Publication date: 1979-08-21

Abstract

Abstract of the Disclosure There is described a method for forming a two-way wall pouch, including advancing a first set of two separate films of flexible transparent material, simultaneously advancing a second set of two continuous films of flexible transparent material, and momentarily spacing the two films of one of the sets and feeding a continuous flexible strip on which intelli-gence material has been printed between the films of the first set of films. The first and second sets of films are advanced, and the edges of the first and second sets of films are heat sealed in a four-ply unit with the label connected at the bond of the heat seal, and separating each so-formed double walled bulk container from the continuous series.

Description

The present invention relates to flexible containers, and more particularly, to a transparent type of flexible con-tainer for use in containing liquids directed for human consumption.
In the bulk liquid container field, particularly with regard to servicing restaurants and the like, a five-gallon size container has been found to be the best size of container. In the past, milk was delivered to restaurants and public dining facilities in metal containers. Then came the advent of the corrugated carton having a polyethylene liner fixed to the inside of the carton, and a heavier density polyethylene spout attac~ed to both the liner and the carton. These containers were ideal for stacking and for handling, and the costs of shipping were reduced since the containers were disposible. However, with the ever-increasing cost of fiberboard material, such as corrugated boxes, a new flexible disposible pouch has been d~veloped to replace the corrugated box with the liner container.
The newer container is in the form of a five-gallon pouch made up of a double wall of polyethylene material with a heavier density polyethylene spout piercing a wall of the pouch and adhered thereto in a peeled manner.
In the era of the carton box with the polyethylene liner, it was reasonably easy to identify the product, the date the product was filled in the flexible container, and the trade mark label of the dairy supplying the bulk milk, since this need merely be adhered to the outer box or printed thereonO
However, there are problems in labeling the present flexible pouch made up of transparent polyethylene sheet material. It is well known to print on such polyethylene sheet material by first treating the sheet material with a corona discharge.
~lowever, sheet material which has been treated by corona dis-charge tends to be less susceptible to heat sealing, and a strong - 1 - ~

z heat seal bond is essential when one is dealing with five-gallon liquid pouches.
It is an aim of the present invention to provide an economic flexible transparent wall bulk liquid container with a suitable identification label.
It is also an aim of the present invention to provide an improved method for forming a flexible wall transparent con-tainer having a label incorporated therein.
In a construction in accordance with the present inven-tion, there is provided a container, the walls of which are oftwo-ply thickness and at least the outer ply being transparent, an identifying label strip provided within the two plies of a wall of the container and connected to opposed heat seal bonds forming the container ends such that the label strip is held at either end to the heat seal bond.
In a method in accordance with the present invention, thera is provided a continuous process for forming two-ply walled pouches, including advancing from a single roll a first set of two separate films of flexible transparent material, simultaneously advancing a second set of two continuous films of flexible transparent material, momentarily spacing two films of one of the sets and feeding a continuous flexible strip on which intelligence material has been printed, between the films of the first set of films, advancing the first and second sets of films, heat sealing the edges of the first and second sets of films in a four-ply unit with the label connected at the bond of the heat seal, and separating each so-formed double walled bulk container from the continuous series.
Having thus generally described the nature of the invention, reference will now be made to the accompanying draw-ings, showing by way of illustration, a preferred embodimen-t thereof, and in which Figure 1 is a perspective, partly fragmentary view of a !~ -- 2 --container having a label in accordance with the present invention;
Figure 2 is a vertical elevation, schematically representing the feed unit of a pouch forming apparatus, and Figure 3 is a cross-sectional view taken through lines 3-3 of Figure 1.
Referring now to the drawings, there is shown a flexible container only partly separated from a continuous series of similar containers 10. Each container 10 includes a spout 12 and a label strip 14. The container is formed with four film thicknesses of polyethylene material forming a double walled pouch. As shown in Figure 3, the container 10 can have the film 16, 18, 20 and 22 with a heat seal bond 24 on either longitudinal edge thereof and lateral heat seal bonds 26 along the lateral edges thereof.
As shown in Figures 1 and 3, the container 10 is approximately 23 inches square, and each film 16, 18, 20 and 22 is approximately 2 to 3 mils in thickness. On the other hand, the label strip 14 which could be of a thinner polyethylene would be approximately .5 to 1 mil thick. m e label strip 1~
would be a narrow continuous strip which may have been treated with corona discharge or other process in order to make it more susceptible to printing. The printed label portion would be intermittently printed on the strip, thereby leaving a space ~ between the printed label on the strip in the area of bonding.
! It has been found that the heat seal bond does not take too well ! over the printed material.
The spout is heat sealed in a continuous process for making the pouch and is welded to the upper two films 16 and 18 making up one of the walls of the pouch.

By placing the label as such between two layers making 5;~

up one wall of the pouch, it is readily visible from outside the pouch, and the strip can, of course, be custom fitted according to a client's requirements. By providing such a strip of printed film, it is not necessary to treat the outer pouch for receiving labels and, therefore, it does not interfere with the actual structure of the pouch.
Referring now to Figure 2, a feed mechanism for making up a series of double walled flexible polyethylene pouches is shown at 30. A pair of rolls 32 and 34 are provided, and these rolls each supply a double film of polyethyle~ne sheet material in the proper size. If the feed mechanism is automatic in nature, alternate feed rolls can be provided, as shown in dotted lines. As shown, the films 16 and 18 are paid off from the roll 32 and proceed towards the heat sealing station. However, a roller 36 forces the films 16 and 18 to be spread apart and a label strip supply roller 38 is provided between the films 16 and 18 and supplies a continuous label strip 14. The roller 38 can be controlled to retard and therefore stretch slightly the label strip 14 so as to centrally locate the printed label area of the strip as it is being fed in the pouch assembly. Finally, the other double wall is formed by supplying films 20 and 22 of suitable polyethylene material in the same manner over a series of rollers to the heat seal station, not shown. The four layers, 16, 18, 20 and 22, are then heat sealed in a conven~ional manner, and the heat seal process also binds the edges of the strip of the label film 14 at 26.

Claims

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

1. A flexible transparent pouch having at least a double wall, a heat sealed bond at the extremities thereof, a strip of flexible material having a label extending between the bonds and located between a pair of films making up the double wall, the strip being connected to the extremities of the container at the heat seal bonds.

2. A flexible transparent pouch as defined in claim 1, wherein the label strip is a film of polyethylene having a thickness between .5 to 1 mil.

3. A flexible transparent pouch having at least a double wall, a heat sealed bond at the extremities thereof, a strip of flexible material on which a label has been printed extending between the bonds and located between a pair of films making up the double wall, the strip being connected to the extremities of the container at the heat seal bonds, the label area includ-ing the printed intelligence being spaced from the heat sealed bonds of the pouch forming the label so as not to interfere with the bond.

4. A method of producing a double layer pouch of trans-parent flexible material, including simultaneously feeding four continuous films towards a pouch assembly and interposing and feeding a continuous strip of material having label intelligence thereon between two of the films making up the double wall of the container, heat sealing spaced-apart lateral bonds forming the pouches therebetween and holding the ends of the label strip extending between the bonds, and separating each so-formed double wall bulk container from the continuous series.

5. A method as defined in claim 4, wherein spaced-apart label intelligence is printed on the strip and the further step of coordinating the label intelligence printed on the strip such that the bond is made on an unprinted area of the strip between the printed label and intelligence areas.