WO2008035082A1

WO2008035082A1 - Method and apparatus for manufacturing a food packaging container

Info

Publication number: WO2008035082A1
Application number: PCT/GB2007/003577
Authority: WO
Inventors: Peter Davies; Michael John Flaherty
Original assignee: Procurasell Holdings Limited
Priority date: 2006-09-20
Filing date: 2007-09-20
Publication date: 2008-03-27
Also published as: GB0618489D0; GB2444913A; GB2444913B

Abstract

This invention relates to a method of manufacturing a food packaging container, an apparatus for manufacturing a food packaging container and a food packaging container produced according to the method. This invention relates to a method and apparatus for manufacturing food packaging containers with a peelable lid from sugar cane pulp. The resulting container being capable of holding a variety of foodstuffs and is, after use, entirely biodegradable and compostable. To manufacture the food packaging container, a two-stage moulding process is utilised. In particular, following the introduction of a water-based sugar cane pulp solution to a moulding chamber, the water is then extracted from the sugar cane pulp solution through a meshed first tooling head which defines an approximate profile of the food packaging container. Subsequently, the sugar cane pulp profile obtained is then transferred to a second tooling head and appropriate pressure and heat applied.

Description

METHOD AND APPARATUS FOR MANUFACTURING A FOOD PACKAGING CONTAINER

This invention relates to a method of manufacturing a food packaging container, an apparatus for manufacturing a food packaging container and a food packaging container produced according to the method. In particular, this invention relates to a method and apparatus for manufacturing food packaging containers from sugar cane pulp. The resulting container being capable of holding a variety of foodstuffs and, after use, is entirely biodegradable and compostable.

Insofar as much of the western world is concerned, the ready meals market has grown considerably in recent years. Consumer demand for convenience foods, a rise in freezer and microwave oven ownership, and an increase in one and two-person households are all factors driving this market. Hitherto, the most popular material for ready meal containers has been PET (polyethylene terephthalate) and PEN (polyethylene naphthalate) which are polymers having advantages in terms of costs, good thermostability and lightweight. In use, this type of container does have a number of shortcomings and after re-heating the foodstuff, it is often found that the rigidity of the container decreases which can be dangerous and also makes it difficult to remove the foodstuff form the container. Also, the adhesive seal between the container and the (supposedly) peelable petrochemical derivative-based film is often not of a uniform quality, leading to a film which either degenerates during re-heating or is exceedingly difficult to remove. From an environmental point of view, whilst these plastic PET or PEN products can be recycled where appropriate facilities exist, the industry is still struggling to keep pace with growth of the virgin product, and millions of plastic containers are still buried in landfill sites every year. Another well-known environmental problem is that these plastics are manufactured from non-renewable resources such as oil, coal and natural gas.

It is therefore an object of the present invention to provide a method and apparatus for manufacturing food packaging containers that is guick and straightforward to manufacture. The food packaging container according to the present invention can be manufactured quite readily using a raw material, namely sugar cane pulp, which is a sustainable crop. After use, the container is entirely biodegradable and is, in fact, compostable in around 12 weeks. The food packaging container according to the present invention also exhibits increased mechanical rigidity enabling ease of handling of the re-heated foodstuffs. The outer rim dimensions of the food packaging container are designed to facilitate a peelable seal with a lid formed from sugar cane pulp, and no adhesives are used. In use, the thermal properties of the food packaging container according to the present invention are such that a user can safely remove the container from the oven without insulated oven gloves. According to the present invention there is provided a method of manufacturing a food packaging container, comprising the steps of: introducing a water-based sugar cane pulp solution to a moulding chamber; extracting said water from said sugar cane pulp solution through a meshed first tooling head which defines an approximate profile of the food packaging container; and transferring the sugar cane pulp profile obtained to a second tooling head and applying pressure and heat.

Also according to the present invention there is provided an apparatus for manufacturing a food packaging container, comprising: at least one moulding chamber containing a suitable quantity of water-based sugar cane pulp solution; extracting means for extracting said water from said sugar cane pulp solution through a meshed first tooling head which defines an approximate profile of the food packaging container; and means for transferring the sugar cane pulp profile obtained to a second tooling head and applying pressure and heat.

Further according to the present invention there is provided a food packaging container formed from sugar cane pulp, the food packaging container comprising: at least one compartment defining a base, side sections and peripheral outer rim, said at least one compartment being suitable for containing foodstuffs; a plurality of indents situated on said base and/or said side sections to provide mechanical rigidity; and a peelable lid portion formed from said sugar cane pulp, said peelable lid being attached to said peripheral outer rim under the application of pressure and heat only.

Preferably, the present invention further comprises the step of rolling and compressing the water-based sugar cane pulp solution to form a lid.

In use, the present invention further comprises the steps of transferring at least one food product to said food packing container and aligning said food packing container and said lid and applying pressure and heat to form a peelable seal.

Further preferably, the step of extracting said water from said sugar cane pulp solution through a meshed first tooling head is performed using under vacuum. The water-based sugar cane pulp solution may also include additives to provide oil, chemical and water resistance in the finished product.

Preferably, the second tooling head is substantially solid and includes raised features for embossing the manufacturers' logos and/or food grade standards and/or a plurality of indents.

In use, the plurality of indents on said second tooling head allow for increased mechanical rigidity and/or mechanical de-nesting of a plurality of said food packaging containers.

It is believed that a method and apparatus for manufacturing a food packaging container in accordance with the present invention at least addresses the problems outlined above. In particular, the advantages of the present invention are that a method and apparatus for manufacturing food packaging containers is provided that is quick and straightforward to manufacture. Advantageously, the food packaging container according to the present invention can be manufactured quite readily using a raw material, namely sugar cane pulp, which is a sustainable crop. After use, the container is entirely biodegradable and is, in fact, compostable in around 12 weeks. Further advantageously, the food packaging container according to the present invention also exhibits increased mechanical rigidity enabling ease of handling of the re-heated foodstuffs. The outer rim dimensions of the food packaging container are advantageously designed to facilitate a peelable seal with a lid formed from sugar cane pulp, and no adhesives are used. Further advantageously, the thermal properties of the food packaging container according to the present invention are such that a user can safely remove the container from the oven without insulated oven gloves.

It will be obvious to those skilled in the art that variations of the present invention are possible and it is intended that the present invention may be used other than as specifically described herein. A specific non-limiting embodiment of the invention will now be described by way of example and with reference to the accompanying drawings, in which:

Fig. 1 shows a perspective view from above of one type of food packaging container that can be produced according to the present invention;

Fig. 2 illustrates a perspective view of the bottom of the food packaging container shown in Fig. 1 ;

Fig. 3 shows a perspective view from above of a further type of food packaging container that can be produced according to the present invention;

Fig. 4 illustrates a perspective view of the bottom of the food packaging container shown in Fig. 3;

Fig. 5 shows a further perspective view of the bottom of the food packaging container shown in Figs. 3 and 4;

Fig. 6 illustrates a perspective view from above of the food packaging container shown in Fig. 1 with a lid attached;

Figs. 7 and 8 show side perspective views of the food packaging container shown in Fig. 6 after the food contents have been re-heated in an oven.

Referring now to the drawings, various types of food packaging container that can be produced according to the present invention are illustrated in Figs. 1 to 8. The food packaging container trays shown in Figs. 1 to 8 consist of a tray 10 having an outer rim 12 which defines at least one compartment which, in use, accommodates the food product (not shown) which can be subsequently frozen, chilled or ambient. Design features in each tray 10 enable the present invention to be easily and successfully integrated onto all production lines used by various food manufacturers.

In particular, each tray 10 has a series of indents 16 situated around the base, which enhances both vertical and horizontal strength. Triangular indents 18 located on the top surface of the tray increase the ability of the present invention to remain rigid throughout the packaging cycle and in use.

The outer rim 12 dimensions of each tray 10 are designed to facilitate a peelable seal with a lid 20, when bonded together, and as shown in Figs. 6 to 8. The bonding process of the lid 20 to the rim 12 of the tray 10 is achieved by heat and pressure only; no adhesives are used which would compromise the 100% integrity of the biodegradable and compostable pure sugar cane.

The raw material used to manufacture the food packaging trays 10 according to the present invention product is pure sugar cane reclaimed after the extraction of the sugar. The manufacture of trays 10 follows a number of processing steps, as described below. In essence, the raw material (pure sugar cane reclaimed after the extraction of the sugar) is processed to form a pulp. The pulp is then introduced to moulds, which press the raw material to the required shape. The pulp is also rolled and compressed to create the former for the lids 20. After filling the compartment 14 with the various food product or products (not shown) , the food containers 10 and lids 20 are aligned in packaging equipment and are formed together using suitable heat and pressure .

This is the only product which has the ability to weld to itself and retain its integrity at -40°C and in an oven at 220°C. After use, the product is totally biodegradable and, in fact, is compostable. There is no requirement to coat the trays with petrochemical derivatives as the finished goods are tested to European food grade standards and meet all the legislation for food contact trays.

Further detail of the manufacturing process will now be described. In particular, sugar cane cultivated from plantations is transported to the manufacturing facility, and the sugar cane then processed into sheet form. These sugar cane sheets are then pulverised into microparticles . The pulverised cane is then added to a water-based solution containing additives for oil, chemical, and water resistance in finished product. Following this the raw pulp solution is stored in large silos which provide constant mixing. To form the moulded trays 10, a two-stage moulding process is utilised. The first stage of the process involves the pressurised extraction of the raw pulp solution from the silo. The pulp is then added to a precise volume of water in a moulding chamber which completely covers the metal mould profiles for whichever design is being manufactured.

Using vacuum extraction, the water is then expelled from the mould chamber leaving a uniform layer of pulp as the design profile. This is possible by using a first tooling head formed as a wire mesh which allows the water in the solution to be extracted.

This pulp profile is then transferred to a second tooling head where controlled pressure and heat are applied to provide the finished product.

Individual design features (such as embossing of manufacturers' logos; food grade standards and a plurality of indents) are present on the second tooling head to allow for mechanical sealing of cane lids 20 and mechanical de-nesting of finished products required by the food processing industry.

Various alterations and modifications may be made to the present invention without departing from the scope of the invention.

Claims

1. A method of manufacturing a food packaging container, comprising the steps of: introducing a water-based sugar cane pulp solution to a moulding chamber; extracting said water from said sugar cane pulp solution through a meshed first tooling head which defines an approximate profile of the food packaging container; and transferring the sugar cane pulp profile obtained to a second tooling head and applying pressure and heat.

2. The method of claim 1, further comprising the step of: rolling and compressing said water-based sugar cane pulp solution to form a lid.

3. The method of claim 2, further comprising the steps of: transferring at least one food product to said food packing container; and aligning said food packing container and said lid and applying pressure and heat to form a peelable seal.

4. The method of claims 1 or 2, wherein the step of extracting said water from said sugar cane pulp solution through a meshed first tooling head is performed using under vacuum.

5. The method of claims 1 or 2, wherein said water-based sugar cane pulp solution includes additives to provide oil, chemical and water resistance.

6. The method of claim 1, wherein said second tooling head is substantially solid and includes raised features for embossing the manufacturers' logos and/or food grade standards and/or a plurality of indents.

7. The method of claim 6, wherein said plurality of indents on said second tooling head allow for increased mechanical rigidity and/or mechanical de-nesting of a plurality of said food packaging containers.

8. An apparatus for manufacturing a food packaging container, comprising: at least one moulding chamber containing a suitable quantity of water-based sugar cane pulp solution; extracting means for extracting said water from said sugar cane pulp solution through a meshed first tooling head which defines an approximate profile of the food packaging container; and means for transferring the sugar cane pulp profile obtained to a second tooling head and applying pressure and heat.

9. The apparatus of claim 8, further comprising means for rolling and compressing said water-based sugar cane pulp solution to form a lid.

10 The apparatus of claim 9, further comprising: means for transferring at least one food product to said food packing container; and alignment means for aligning said food packing container and said lid and applying pressure and heat to form a peelable seal.

11. The apparatus of claims 8 or 9, wherein extracting means for extracting said water from said sugar cane pulp solution through a meshed first tooling head is performed using under vacuum.

12. The apparatus of claims 8 or 9, wherein said water-based sugar cane pulp solution includes additives to provide oil, chemical and water resistance.

13. The apparatus of claim 8, wherein said second tooling head is substantially solid and includes raised features for embossing the manufacturers' logos and/or food grade standards and/or a plurality of indents.

14. The apparatus of claim 13, wherein said plurality of indents on said second tooling head allow for increased mechanical rigidity and/or mechanical de-nesting of a plurality of said food packaging containers.

15. A food packaging container formed from sugar cane pulp, the food packaging container comprising: at least one compartment defining a base, side sections and peripheral outer rim, said at least one compartment being suitable for containing foodstuffs; a plurality of indents situated on said base and/or said side sections to provide mechanical rigidity; and a peelable lid portion formed from said sugar cane pulp, said peelable lid being attached to said peripheral outer rim under the application of pressure and heat only.

16. The food packaging container of claim 15, wherein said sugar cane pulp includes additives to provide oil, chemical and water resistance.

17. The food packaging container of claim 15, wherein said plurality of indents aid mechanical de-nesting of a plurality of said food packaging containers.

18. A method of manufacturing a food packaging container as hereinbefore described.

19. An apparatus for manufacturing a food packaging container as described herein with reference to Figs. 1 to 8 of the accompanying drawings.

20. A food packaging container as described herein with reference to Figs. 1 to 8 of the accompanying drawings.