AU2002313991A1 - Improved packaging system - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): MIKE MARKHAM Invention Title: IMPROVED PACKAGING SYSTEM The following statement is a full description of this invention, including the best method of performing it known to me/us: IMPROVED PACKAGING SYSTEM TECHNICAL FIELD This invention relates to improvements made to packaging systems. Preferably the present invention may be adapted to provide a ventilated bag which can be manufactured easily and inexpensively using plastic materials.

BACKGROUND ART Many different types of packaging has been developed to secure and protect goods during transportation, display or storage. For example, bags of all forms and shapes are commonly used to secure a number of articles in a single container.

Plastic bags are very popular in such applications as they may be manufactured quickly, in large volumes and at relatively low cost.

For example, plastic bags can be used to package fresh fruit, vegetables or other produce for the consumer. The plastic materials used can also be printed with suitable advertising or labelling to indicate to the consumer the source and quality of the produce involved.

However, one problem associated with the use of plastic to form such bags is the inability of the plastic to allow gas or air to circulate through the package. The plastic film employed creates a barrier which seals in gases and moisture, which in turn can degrade the appearance and also the quality of produce over time.

One attempt to address this problem in plastic bags is through punching or cutting holes in the layers of film used to form the plastic walls of the bag. A significant number of holes need to be punched into such bags to improve their ventilation capacity. This can in turn significantly slow down the manufacturing process James Wells ref: 28080 employed and can also weaken the inherent structural integrity of the bag if too many holes are punched.

An improved packaging system which addressed any or all of the above problems would be of advantage. A packaging system which could effectively ventilate the contents of a package, and which could be manufactured quickly, easily and at low cost would be of advantage.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

James Wells ref: 28080 DISCLOSURE OF INVENTION According to one aspect of the present invention there is provided a ventilated bag formed from, at least one sheet of substantially continuous film, and at least one sheet of mesh, said mesh being formed from or incorporating a plurality of fibres, whereby the sheet of mesh forms at least a portion of a wall or face of the ventilated bag According to another aspect of the present invention there is provided a ventilated bag substantially as described above wherein said at least one sheet of substantially continuous film is formed from plastic material.

According to yet another aspect of the present invention there is provided a ventilated bag substantially as described above wherein the inner face of a sheet of continuous film is coloured black and the outer face of said sheet is coloured white.

According to a further aspect of the present invention there is provided a ventilated bag substantially as described above wherein said at least one sheet of mesh forms a patch for an aperture formed in a sheet of substantially continuous film.

According to a further aspect of the present invention there is provided a ventilated bag substantially as described above wherein said at least one sheet of mesh forms a strip across the width or length of the bag.

3 James Wells ref: 28080 According to yet another aspect of the present invention there is provided a method of manufacturing a ventilated bag substantially as described above, characterised by the steps of; i) uniting adjacent edges of at least one sheet of continuous film with at least one sheet of mesh, and ii) folding the united sheet over itself, and iii) converting the united sheet material to a plurality of ventilated bags.

According to a further aspect of the present invention there is provided a method of manufacturing a ventilated bag substantially as described above, characterised by the steps of; i) uniting adjacent edges of at least one sheet of continuous film with at least one sheet of mesh, and ii) folding the united sheet over itself, and iii) applying a reinforcing seal to portions of the mesh at set distances along the length of the united sheet, and iv) sealing portions of the united sheet together at set distances along the length of the united sheet, and v) converting the sealed united sheet into a plurality of ventilated bags.

According to yet another aspect of the present invention there is provided a method of manufacturing a ventilated bag substantially as described above, characterised by the steps of; i) forming an aperture within at least one sheet of continuous film, and James Wells ref: 28080 ii) applying a patch formed from a sheet of mesh over said aperture, and iii) folding the patched sheet of continuous film over itself and sealing its adjacent edges to form substantially tubular stock material, and iv) converting the tubular stock material into a plurality of ventilated bags.

The present invention is adapted to provide an improved ventilated bag and methods of manufacturing same. Such a ventilated bag can be employed to promote the free flow of gases into or out of the bag, to in turn ventilate the contents of the bag. The applicant's envision that such ventilated bags may be used to package fresh fruit and vegetable produce, and reference throughout this specification will also be made to the present invention being used in this application. However, those skilled in the art should appreciate that other uses for such ventilated bags are envisioned and reference to the above only throughout this specification should in no way be seen as limiting.

Preferably a bag formed in accordance to the present invention may include at least one sheet of substantially continuous film. Such a sheet of film may be supplied or delivered to a production line to be cut, sealed or converted to form at least a portion of a plurality of ventilated bags. Furthermore, more than one sheet of continuous film may also be employed in conjunction with the present invention if required.

In a further preferred embodiment a sheet of plastics material may form a substantially continuous film as discussed above. Plastics material is relatively inexpensive, lightweight, strong and can readily be printed with high quality graphics and advertising content. The continuous nature of the sheet employed also provides the resulting bag with a significant degree of structural integrity and strength.

James Wells ref: 28080 Those skilled in the art should appreciate that numerous different types and forms of plastic material may be used in conjunction with the present invention. For example, the plastic film employed could be co-extruded, blown film, cast film, or mono-layer blown film in any number of embodiments. Furthermore, such plastic film may be formed from polyethylene resins or starch based resins, and could also have masterbatches, additives, or colorants added. Those skilled in the art should appreciate that the particular application for the ventilated bag will determine the form and type of plastic material employed.

Preferably the plastics material used may also be coloured in some instances. For example, in a further preferred embodiment the side or face of the plastic sheet forming the interior of the bag may be coloured black whereas the opposite outer face of the bag may be coloured white. Black pigment incorporated in the inner face of the sheet will shield the contents of the bag from excessive light levels and potential degradation or exposure to same. The use or application of white pigments initially to the outer face of the plastic sheet allows high quality coloured graphics and advertising material to be applied to the exterior of the bag formed.

Preferably a ventilated bag formed in accordance to the present invention may include at least one sheet of mesh. Such mesh sheets may be formed from or incorporate a plurality of fibres laid over one another form a net or grid work through which air, moisture vapour and other gases can easily pass. The mesh sheet or sheets employed can form at least a portion of a wall or face of the ventilated bag with the size or extent of the mesh portion being determined by the extent which the interior of the bag needs to be ventilated.

The sheet or sheets of mesh employed may be formed from any number of different types of material. For example in some instances any mesh required may be formed from a plurality of polyethylene fibres positioned in a longitudinal and James Wells ref: 28080 transverse array to give the mesh substantially square cross-section apertures or holes. Conversely, other types of fibre may be employed from numerous alternative materials, such as, for example, animal or vegetated fibres, metal wires or any other appropriate material.

In a further preferred embodiment the mesh employed can be formed from a vented fabric known as CLAF8, manufactured by Atlanta Nisseki Claf Incorporated of Atlanta, Georgia, United States. The CLAF' fabric, formed from a cross laminated polyethylene open mesh non woven fabric can provide a suitable mesh sheet to be used in conjunction with the present invention.

The present invention also encompasses a method of manufacturing ventilated bags substantially as described above.

For example, in one embodiment the bags required may be formed with a strip of mesh across the width of one side of the bag. In such preferable embodiments the bag may be formed using standard plastic bag manufacturing and conversion machinery.

However, those skilled in the art should appreciate that the manufacturing technique discussed below may also be employed to form ventilated bags with a strip of mesh running substantially along the length of the bag instead of across its width. Furthermore, those skilled in the art should also appreciate that more than one strip of mesh may also be provided in such ventilated bags if required.

In such instances the adjacent edges of at least one sheet of continuous film and at least one sheet of mesh may be united together. The sheets employed can all be united together at this stage to form a single united sheet of material. The size and placement of the mesh within the bag formed will then be determined by the James Wells ref: 28080 number of sheets of film introduced in addition to the size and placement of the sheet or sheets of mesh used.

Preferably edges or sides of these sheets can be united together using heat seals, adhesives, ultra sonic welds or any other own type of sealing method known in the manufacture of plastic bags.

For example, in a further preferred embodiment the united sheet required may be formed from two sheets of plastic polythene film which are separated by a single sheet of mesh, and have the sides or edges of the mesh bonded and adhered to the adjacent sides or edges of the sheets of polythene film. This united sheet can then be advanced onto further stages of the bag manufacturing process where, across the width of the united sheet, there is provided polythene film, then mesh followed by polythene film again.

After the united sheet has been formed, it may then be folded over itself to form a substantially C shaped arrangement. Preferably the folding of the united sheet may be completed through use of a V-former machine, which is well known in the art.

Once the united sheet has been folded, a reinforcing seal may then be applied to portions of the mesh at set distances along the length of the united sheet. These reinforcing seals may mark out the width of the final bags to be formed and can be made to ensure that the edges of the mesh adjacent to the final edges of the bag are strongly bonded to the edges of the polythene film on the opposite face of the bag.

Preferably, these seals are further reinforced at a following stage of the manufacturing process where a seal is applied across the entire width of the united sheet at set distances along the length of the sheet. This additional lengthways James Wells ref: 28080 seal will divide the folded united sheet into a series of discreet pockets with one open face or end orientated towards the side or edge of the sheet.

Once these lateral seals have been made the united sheets may then be cut to a plurality of separate ventilated bags.

However, those skilled in the art should also appreciate that these seals adapted to mark out each of the bags to be formed may also be made on different portions or areas of the united sheet and other embodiments. For example, in one alternative embodiment where a single layer or strip of mesh is provided running from top to bottom on the ventilated bag a different pattern or arrangement of seals can be applied.

Alternatively, other methods and manufacture of such ventilated bags are also encompassed by the present invention, which need not necessarily employ the united sheet of mesh and plastic films discussed above. For example, in one alternative embodiment a single sheet of plastic film may be supplied to plastic bag conversion machinery. This machinery may cut or form an aperture within the plastic sheet to create a window for a sheet of mesh to cover.

Following the creation of such an aperture a patch of mesh sheeting may then be applied over same and secured in place with adhesive, welds, heat seals or any other type of connection method known in the art. This will then form a sheet of plastic material which incorporates a window covered by a mesh sheet. These operations may be completed consecutively down the length of the main plastic sheet, with one or more mesh-covered apertures or windows being provided for each bag to be formed.

Those skilled in the art should appreciate that a single ventilated bag may include one, two or even more ventilation windows which are patched by the mesh James Wells ref: 28080 material discussed above. Those skilled in the art should appreciate that multiple patched mesh windows may be provided if required in reference to the use of a single window only throughout the specification should in no way be seen as limiting.

Once the aperture or apertures are formed and patched, the patched plastic sheet may then be forwarded or supplied onto standard bag manufacturing or conversing apparatus. This apparatus will normally fold the patched sheet over itself and seal its adjacent edges to form substantially tubular stock material. The stock material can have seals applied along its width to form a number of distinct pockets, which in turn can be cut from one another to form a plurality or ventilated bag.

Furthermore, in any embodiment of the present invention, the method of manufacture employed can also encompass the use of further known bag making machinery to include or incorporate additional features into the ventilated bag.

For example, in some embodiments the ventilated bag may be formed with a reinforced handle with a hole for the centre of the handle being punched out by appropriate machinery. Furthermore, a gusseted bag may be provided with bottom or side gussets, as can bags with flaps and flip-tops.

The present invention may provide many potential advantages over the prior art.

A mesh strip or window provided within such ventilated bags may substantially increase air flows through the bags and also allows for the release of moisture vapour from the bag. This can significantly improve the shelf life of fresh fruit or vegetables packaged within such bags.

Furthermore, the use of a black coloured inner face and initial white outer face in the sheets of continuous film used substantially limits the light levels within the James Wells ref: 28080 bag and also allows high quality graphics and printing to be applied to the exterior of the bag formed.

BRIEF DESCRIPTION OF DRAWINGS Further aspects of the present invention will become apparent from the ensuing description which is given by way of example only and with reference to the accompanying drawings in which: Figure la, lb shows front and side cross-section views of a ventilated bag formed in accordance with a preferred embodiment of the present invention, and Figure 2 shows a front view of a ventilated bag formed in accordance with a further alternative embodiment of the present invention.

BEST MODES FOR CARRYING OUT THE INVENTION Figures la and lb show front and side cross section views of a ventilated bag 1 formed in accordance with a preferred embodiment to the present invention.

The bag 1 is formed from and incorporates plastic sheet or film material 2 making up the main body of the bag. The bag also includes a mesh ventilation panel 3 running across the width of the bag. In the embodiment shown the mesh panel 3 provides a portion of a wall or face of the bag and therefore allows air, gas, and moisture vapour to enter or escape from the interior of the bag.

At the upper regions of the bag 4 a carry or wicket flap is provided whereas the lower regions of the bag are provided through a rounded loop of plastic film material.

James Wells ref: 28080 A number of distinct seals provided in the construction of the bag 1. A first set of longitudinal seals 6 are applied across the width of the bag to join the adjacent edges of the mesh sheet with those two distinct separate sheets of plastic film.

These seals form a united sheet of material which in turn is folded over itself and sealed at appropriate areas to form the bag 1 shown.

Reinforcing welds 7 are also applied to the edges of the ventilation panel 3 to securely bond the edges together and also to the adjacent portions of the plastic sheet material directly underneath the area of the reinforcing seal 7. This feature of the bag 1 is not shown with respect to figure lb as a cross-section view of the interior of the ventilated bag is shown.

The bag also includes a set of side seals or welds 8 running across the length of the bag 1 formed. These side seals run the entire length of the bag and in the production line operation divide the united sheet employed into a plurality of the distinct ventilated bags.

The final top seal or other closure method is also provided when the bag 1 has been filled with its contents and is to be closed. The bag may be manufactured without this top seal, which can be applied by those filling and ultimately distributing the ventilated bag.

Figure 2 shows a front view of the ventilated bag formed in accordance with a further alternative embodiment to the present invention.

Again, the ventilated bag 11 has its main body 12 formed from the plastic sheet material. However, in this instance the bag includes a ventilation window 13 formed from a aperture or hole punched through the plastic sheeting which is patched in turn by a sheet of mesh material.

12 James Wells ref: 28080 The bag 11 formed in this instance is initially created through a single sheet of plastic material with the window or hole being cut from the sheet. This hole is then patched with the mesh sheet 13 shown, with the mesh then having a series of reinforcing or securing seals 14 made between the layer of plastic sheet and the material forming the mesh.

Once this single sheet of plastic has been patched, it is then folded over itself and has its edges sealed to form substantially tubular stock material. This tube stock material can then be forwarded onto standard bag conversion production line to have a bottom weld 15 applied, where the final bag produced has an open of end 16 which corresponds to the separation point of the bag from its adjacent neighbour's bottom seal.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims.

James Wells ref: 28080

Claims (1)

1. 21. A ventilated bag substantially as herein described with reference to and as illustrated by the accompanying drawings and/or examples. Dated this 29th day of November 2002 MIKE MARKHAM By their Patent Attorneys GRIFFITH HACK James Wells ref: 28080