WO2007072030A2

WO2007072030A2 - A stack of bags, apparatus for making a stack of bags and a method of making a stack of bags

Info

Publication number: WO2007072030A2
Application number: PCT/GB2006/004875
Authority: WO
Inventors: Adam Dickinson
Original assignee: Euro Packaging Ltd
Priority date: 2005-12-21
Filing date: 2006-12-21
Publication date: 2007-06-28
Also published as: GB0525964D0; WO2007072030A3

Abstract

A stack of bags comprising a plurality of bags having a first design, material or colour and a bag having a first design, material or colour an a bag having a second, different design, material or colour in the stack. An apparatus for making a stack of bags comprising a first reel of bag material, the bags having a first design, colour or material or two which said first design or colour is to be applied, a second reel of bags material having a second, different design, colour or material or to which the second, different design or colour is to be applied and means to form a bag form a bag length of bag material from the second reel and to introduce a bag so formed into bags formed from the bag material on the first reel. A method of making a stack of bags comprising providing a first reel of bag material having a first design, colour or material or to which a first design or colour is to be applied, providing a second reel of bag material having a second design, colour or material or to which a second design or colour is to be applied, feeding material from said first reel to means for forming a bag, applying the first design or colour, where not already applied, feeding material from said second reel to the means for forming a bag, applying the second design or colour where not already applied and arranging bags from the first and second reels into a stack.

Description

A stack of bags, apparatus for making a stack of bags and a method of making a stack of bags.

This invention relates to the introduction of a single or plurality of differentiated products of a similar nature, by colour, print, size and or shape in a manufacturing process that is continuous.

One such product is a carrier bag or other flexible film product. Alternatively the process may be applicable to other known forms of products that are produced from a continual reel of material.

A carrier bag can be characterised in that the bag is formed of a flexible sheet of plastic material either tubular or flat, whereby the length of material has a top end and a base end so formed with a seal and a cut thereby separating the designated length of film from the continual reel of preextruded material. The length of material is placed in register on top of other like lengths of material in a stack or bundle. The bag stack is presented to a punching process whereby the material of the body of the bag is cut away form the top of the bag length to a distance preferably approximately one third of the length of the bag. Either side of the cut remains material that will form the handles of the carrier bag. Advantageously, if the body of the film length is formed with gussets then the handles have 4 ply of material once the bunch out is completed. It is advantageous that differing forms can be introduced in the areas of the lunch out for advantageous functional benefit such as forming part of a dispensing mechanism, whereby the block of material remaining can severably attach the inside of the handles to the mouth of the bag. A "hot pin" feature is used to bind the bar block material together in order to retain the bags in the stack, and then when the bags have been depleted the block of waste material together. It is known that in the production of such articles as for example carrier bags, the production process is continuous and could furthermore be described as being continuous product of a sheet like material direct from an extruder die which has fixed parameters. These fixed parameters allow for the required dimensional size and thickness to be achieved form the outset of the extrusion of the material. Furthermore, this material can be printed onto using flexographic print or gravure print dependent of the manufacturing machinery. The extruded material can also be coloured by the introduction of pigment or colorant into the resin in order that the base material produced is a specific colour as opposed to natural.

The introduction of a different masterbatch to the extrusion process can provide a change in colour to the base extruded material although it will slowly blend into the prior material colour, until after a due period of time the new colour will preside in totality. To revert, the same is true. This method does not offer any opportunity in which to provide for example 1 bag length that is a 2^nd colour amongst a continuous production of a 1^st colour.

Masterbatch is an additive package, added into the base resin that is to be extruded, providing differing colours or functional benefits.

The term design relates to the two dimensional representation of a printed image or the three dimensional form and function of the intended product.

That said constant manufacturing process produces a large amount of material either printed or plain that is converted into a bag by the use of a machine that takes the continuous length of material and cuts and seals it to the required length. Each cut length of material is stacked and then typically punched with a handle profile. Therefore every bag in the bag stack is the same material, colour, print, design and has a similar functional benefit.

The introduction of a differentiated bag or product is to advantageously present the end user with an alternative message or marker indicating the level of usage or alternatively for example presenting an environmental message. It is common in the usage of carrier bags provided in a stack that additional functionality is provided in the stack via the use of glue or other mechanism in order to provide the retailer with improved efficiencies of use. It is therefore advantageous that whilst the users have a disposable attitude to common carrier bags, with the increase in environmental pressures there is a need to communicate to users the impact of their actions, ie bag usage as one example.

The first invention is characterised in that provided are two reels of differentiated design or colour, of a like bag making material from the extrusion process, whereby the bag conversion machine is so produced to feed one bag length from the real designated as two, for any number of bags lengths from reel designated as 1, preferably 1 length from reel two for every 50 lengths from reel one. The introduction of the 2 materials in the said manner allows the end bag stack to have, contained in the body of the stack any number of differentiated products. The number of introduced products is discretionary, but could range from 1 in a million to 1 in two. The two reels of film axe presented to the sealing and cutting area in register, on an instruction, either manually or automated, the feed will be alternated from the first reel to the second. This action is a smooth transition between the two and allows for any number of bags to be interchanged from one reel or the other, for example 100 bag lengths from reel one followed by 20 bag lengths from reel two, or this may completely random.

A second embodiment is characterised in that there are reels presented to the bag conversion machine in numbers greater than 1. For example 3 differentiated reels may be provided in that 1 in every 3 bags is of a differentiated design from the prior or that the differentiated bags from each of the unique designs can be introduced at random. For complex introduction a PC may act to provide the control of the activation and therefore resulting insertion of each bag length.

A third embodiment is characterised in that the differentiated bags are introduced at such a point in the bag conversion machine that the bonding of a "hot pin" is undertaken after the differentiated bags have been introduced into the bag stack. A hot pin is typically introduced in the area of a bar block between handles of a carrier bag in order that the stack of bags are bonded together. This facility often is associated with a dispensing mechanism of the bag stack. Alternatively any other form of bonding of the bar block will achieve the same and, for example, self adhesive tape, string or other suitable binding.

AU in which the introduction of the differentiated reels may not be exclusively a "usable bag foπn" it may be a single ply of paper, plastic or other like material that can be introduced in the said manner, it is advantageous that the alternate material is a similar length to that of the bags in the stack although the width may be variable. An additional invention relates to the introduction of a print mechanism that is capable of changing the whole or part printed image on the continual reel of film without the need to stop the flow of the material. The printed image may be provided different on every reproduced length of material or, as per the first invention, introduce a differentiated image for example. 1 in every 50 lengths required for bag making.

Further characterised in that the inkjet technology is used in place of the traditional print reprographics so that via the operation of a PC each printed length is a different design running on a continual basis.

The use of inkjet technology may form part of an inline process with extrusion or may be a lone standing machine process whereby a reel of imprinted bag material is provided to the printer. As the material is wound reel to reel the inkjet image is applied on a consistent or varying basis.

Further characterised in that the inkjet technology is used in conjunction with traditional technology to replace a part of whole of the image. The intention ϊ$ that a consistent background image may be used whereby the use of the inkjet print provides a variable message that is placed within the fir$t reproduced image formed of the flexographic or gravure print process.

A further invention relates to the interjecting use of a number of print stations greater than 1 whereby the print station can be activated and deactivated on a length by length basis to have a selection action between two or more differing printed images. The printing mechanism being so formed so one print station will miss an impression or multiple impressions as the second station will print in register in the void left by the first print station. The end result is such that, for example, 1 bag length per million or 1 bag length in every 2 may have a differentiated image in colour or design.

Claims

CLAIMS:- t . A stack of bags comprising a plurality of bags having a first design, material or colour and a bag having a first design, material or colour and a bag having a second, different design, materia) or colour in the stack.

2. An apparatus for making a stack of bags comprising a first reel of bag material, the bags having a first design, colour or material or to which said first design or colour is to be applied, a second reel of bags material having a second, different design, colour or material or to which the second, different design or colour is to be applied and means to form a bag from a bag length of bag material from the second reel and to introduce a bag so foππed into bags formed from the bag material on the first reel.

3. An apparatus for making a stack of bags according to claim 2 in which further such reels are provided.

4. An apparatus for making a stack of bags according to claim 2 or 3, in which means for hot pinning the stack of bags is provided subsequent to the introduction of the bag or bags with the second, different design, colour or material.

5. A method of making a stack of bags comprising providing a first reel of bag material having a first design, colour or material or to which a first design or colour is to be applied, providing a second reel of bag material having a second design, colour or material or to which a second design or colour is to be applied, feeding material from said first reel to means for forming a bag_> applying the first design or colour, where not already applied, feeding material from said second reel to the means for forming a bag, applying the second design or colour where not already applied and arranging bags from the first and second reels into a stack.

6. The method of claim 5 in which the first and/or second design is applied by ωlcjet printing.

7. A method of applying a design to a vest style carrier bag comprising iukjet printing said design on said bag.