IMPROVED COMPOSITIONS, CONTAINERS AND/OR LIDS, AND THEIR METHODS OF MANUFACTURE

Field of Invention

The present invention relates to improved compositions, containers and/or lids, and their methods of manufacture. In one form, the invention relates to an improved compostable container and/or lid for storing food or liquids. The containers may have lids contiguous/integral to their body or separate from their body.

Background to the Invention

Consumers have a wide variety of choices when it comes to purchasing hot or cold beverages for consumption. Typically, pre-prepared beverages that are made offsite are sold in recyclable containers such as glass or plastic bottles or aluminium cans.

For beverages that are made fresh onsite, such as coffee, smoothies, juices and the like, these may be provided in disposable single use containers with separate lids for consumers to take away off site.

Disposable cups and lids generally made from plastics or plastic lined paper are a commonly used alternative to reusable drinking cups for their low cost and convenience. However, cups and lids made exclusively from plastic are typically unsuitable for holding hot beverages. It would be preferable to move away from non renewable virgin resources to renewable circular resources.

While containers and lids can be made from recyclable plastic, a large proportion of these containers and lids still often end up in land fill as consumers discard them once they have consumed the contents of the beverage. Additionally recycling facilities will typically only accept recyclable materials that are clean. Any soiled or contaminated containers may be regarded as unsuitable for recycling and are commonly discarded to general refuse by the recycling facility.

While the term "biodegradable" means capable of being substantially broken down by living organisms (including bacteria), the degree to which an item is "biodegradable" or "compostable" is not standardised. For instance, 76% of New Zealanders surveyed believe that the current "compostable" coffee cups can be disposed of in domestic compost bins and will readily decompose. Only 16% are aware that these cups are quite difficult to compost and require commercial/industrial facilities to break down completely. Compostable packaging, including PLA hot cups, are made with a bioplastic lining. This lining is made from plants which reduces the use of fossil fuels. The product itself is a polymer, but the polymer is made from renewable resources.

Compostable cups cannot be recycled in the paper and cardboard recycling stream and need to be collected separately for commercial composting. This is due to the limitations with separating the lining from the paper fibre. Despite some claims that they can be placed in the mixed kerbside recycling bin, a Material Recovery Facility cannot process takeaway cups for recycling and they are diverted to landfill. In the United Kingdom it has been found that only 1 in 400 coffee cups gets composted.

PLA packaging composts under specific conditions as defined by the EU standard EN13432. These conditions are present at some specialised commercial composting facilities. Industrial or commercial composting can be defined as the controlled biological decomposition of organic waste under management conditions that are predominantly aerobic (ie. In the presence of oxygen) and that allow the development of thermophilic conditions as a result of biologically produced heat. Thermophilic conditions describes heat temperature in the range 50-65 °C or higher. In contrast, domestic or home composting describes a cooler aerobic breakdown of organic material or waste, usually in smaller composters and by a "slow stack" method. Temperatures are in the psychrophilic (0-20 °C) to mesophilic (20-45 °C) ranges. The volumes treated in domestic composting are considerably smaller than industrial composting and the compost is predominantly used in private gardens.

PLA cups are not engineered to break down in home composting environments, and need to be collected for commercial composting to ensure the cups are able to be processed and broken down alongside food or organics products. The infrastructure required to recover cups and lids from the appropriate accumulation points is seldom in place.

Biodegradation of bioplastics occurs through two primary mechanisms: physical and biological. Physical degradation includes processes such as hydrolysis and photodegradation, which can lead to partial or complete degradation. Biological degradation can be further divided into aerobic and anaerobic mechanisms.

Aerobic degradation of compostable plastics uses oxygen and the general equation for degradation follows:

Anaerobic degradation of compostable plastics does not use oxygen and results in the creation of methane, a potent greenhouse gas, using the following general mechanism:

Cpolymer Cresidue + Cbiomass + CH ₄ + CO ₂ + H ₂ O Diverting organics waste to landfill increases the risk of compostable coffee cups and their lids breaking down and releasing methane, in addition to carbon dioxide, water and biomass. This is because landfill composting conditions are not controlled and are suboptimal.

Styrofoam and paper cups lined with a plastic water-proof layer have been used for holding hot liquids for extended periods of time. However, such cups are also not good for the environment as they are not biodegradable, they litter the environment and end up in landfills. In addition, the plastics used in disposable cups are typically derived from fossil fuels.

Such disposable single-use containers are steadily becoming economically and societally undesirable. Greater awareness around environmental impacts and sustainability are driving businesses and consumers to become more conscious with their decisions to seek more environmentally friendlier options.

Object of the Invention

The following outlines a number of objects, at least one of which may advantageously be addressed by the present invention.

It is an object of the invention to provide an improved container and/or lid that at least overcomes one or more of the disadvantages mentioned above.

It is an object of the invention to reduce, or even avoid the unnecessary use of non renewable resources.

It is an object of the invention to avoid or reduce the quantity, toxicity and/or ecological footprint of use and consumption.

It is a further object of the invention that the container and/or lid are able to fully compost under the more challenging conditions of domestic decomposition.

It is an object of the invention that the container and/or lid may be edible.

It is an object of the invention to provide the public with an edible, allergen friendly container and/or lid.

Alternatively, or in addition, it may be an object of the invention to provide the public with a useful choice. Summary of the Invention

Given the constraints over raw materials that would be available for use in the manufacture of such a container or its lid, the inventors gave consideration to food materials that might be adapted to serve the same function as the non food materials they replace in the manufacture of such containers and their lids, particularly if such containers and their lids were to be used to carry or package foods or beverages. With this in mind, further consideration was given to the allergenicity of those food ingredients and materials. Given the ubiquitous use of some types of food and beverage containers and their lids such as coffee cups and lids, the inventors considered that ideally it would be an advantage that the materials and ingredients used in the manufacture of these were free of allergens.

According to a first aspect of the invention, there is provided a container and/or lid adapted to hold hot or cold liquids for an extended period of time, wherein the container and/or lid may be biodegradable.

As used herein, the term "biodegradable" means capable of being substantially broken down by living organisms (including bacteria). Advantageously, the biodegradable compositions of the present invention are preferably configured to biodegrade in normal conditions in a home compost system. Such a system makes effective use of temperatures of less than 50 °C and is to be contrasted with an industrial system which typically makes use of considerably more elevated temperatures (from about 50 °C).

The container and/or lid may be adapted to substantially biodegrade within 12 months of being discarded.

The container and/or lid may be adapted to hold hot or cold liquids for a period of up to 24 hours without substantially deforming.

The container and/or lid may include a wall section having a greater thickness than adjacent wall sections to provide a thermal buffer to reduce heat loss from contents within the container and/or lid and/or allow the container and/or lid to be held more comfortably when handling hot contents. Such a wall section may include pockets of air cells within the matrix of the wall section.

As used herein the term "biodegradable composition" may refer to: a composition in the form of an endproduct that is ready for use - such as a baked composition; as well as a composition that is not in the form of an end-product such as a mouldable composition yet to undergo a moulding step, such as a baking step. In each case it will be appreciated that the biodegradability of the composition is substantially provided by the components used to form the composition, rather than any processing step, such as a moulding step. So, while advantageously the invention provides end-products that are biodegradable under home composting conditions, for example, it is also true that the raw unmoulded mixture will also be biodegradable.

According to another aspect of the invention, there is provided a biodegradable composition for use as a container and/or lid for storing hot or cold liquids, the composition comprising a filler material selected from flaxseed meal, rice bran, coffee grounds (e.g. spent coffee grounds), or other similar high fibre materials that one skilled in the art might substitute, or combinations thereof.

Unless otherwise specified, wt/wt amounts are provided on a wet basis for the biodegradable composition that may then undergo a moulding process. It will be appreciated form the disclosure herein that at least a portion of the water in the wet composition will transition to steam when/if the composition is subjected to the moulding process described herein.

The biodegradable composition of the invention may include flaxseed meal in an amount of at least 10% wt/wt. The biodegradable composition of the invention may include flaxseed meal in an amount of no more than 40% wt/wt, such as no more than 35% wt/wt. The biodegradable composition of the invention may include flaxseed meal in an amount of 10-40% wt/wt, such as 10-35% wt/wt.

The biodegradable composition of the invention may include coffee grounds in an amount of at least 4% wt/wt, such as at least 8% wt/wt. The biodegradable composition of the invention may include coffee grounds in an amount of no more than 20% wt/wt, such as no more than 12% wt/wt. The biodegradable composition of the invention may include coffee grounds in an amount of 4-20% wt/wt, such as in an amount of 8-12% wt/wt.

The biodegradable composition of the invention may include rice bran in an amount of at least 10% wt/wt, such as at least 20% wt/wt. The biodegradable composition of the invention may include rice bran in an amount of no more than 40% wt/wt, such as no more than 30% wt/wt. The biodegradable composition of the invention may include rice bran in an amount of 10-40% wt/wt, such as in an amount of 20-30% wt/wt.

Preferably the biodegradable composition does not include a polymer material such as polybutylene succinate (PBS), Poly Lactic Acid (PLA), Poly Lactide (CPLA), Poly Glycolic acid (PGA), Polyhydroxyalkanoates (PHA), Polyhydroxybutyrates (PHB), Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), Poly Adipate-co- Terephthalate (PBAT) and/or similar materials or combinations thereof. The biodegradable composition of the invention may further include any one or more of: a fat or oil; a matrix forming agent; and fibre, such as crude fibre selected from cereal, tuber, grain, seed or legume or combinations thereof.

The biodegradable composition may include fibre in an amount of at least 10% wt/wt, such as at least 25% wt/wt. The biodegradable composition may include fibre in an amount of no more than 40% wt/wt, such as no more than 35% wt/wt. The biodegradable composition may include fibre in an amount of 10% - 40% wt/wt. Preferably, the fibre is included in the composition in an amount of 25% - 35% wt/wt.

Where present, the matrix forming agent may be starch, such as a starch selected from wheat starch, maize (corn) starch, potato starch, cassava (tapioca) starch, rice starch, glutinous rice starch and/or any combinations thereof. It will be appreciated by one skilled in the art that starch derived from any source may be used as a matrix forming agent in the present invention. The biodegradable composition may include a matrix forming agent in an amount of at least 10% wt/wt, such as at least 25% wt/wt, such as at least 26% wt/wt. The biodegradable composition may include a matrix forming agent in an amount of no more than 45% wt/wt, such as no more than 40% wt/wt. The biodegradable composition may include a matrix forming agent in an amount of 10% - 45% wt/wt; such as in an amount of 25% - 45% wt/wt; such as in an amount of 26-40% wt/wt.

Where present, the fat or oil preferably contains a high level of natural antioxidants. Preferably, the fat or oil may be a vegetable oil, such as a vegetable oil selected from soybean, rapeseed, rice bran, canola, sunflower, safflower, peanut, cottonseed, coconut, palm or any combinations thereof. Where present, the biodegradable composition may include fat or oil in an amount of at least 5% wt/wt, such as at least 7% wt/wt. Where present, the biodegradable composition may include fat or oil in an amount of no more than 20% wt/wt, such as no more than 10% wt/wt, such as no more than 9% wt/wt. Where present, the biodegradable composition may include fat or oil in an amount of 5%-20% wt/wt of the total composition, preferably 5-10% wt/wt, such as 7-9% wt/wt.

The biodegradable composition may advantageously be edible.

The biodegradable composition may optionally include a sweetener. Sweeteners may be selected from sugars, intense sweeteners, sugar alcohols or any combinations thereof. Sugars may include disaccharides and monosaccharides or any combinations thereof. In certain embodiments, disaccharides may include sucrose, lactose, maltose, isomaltose, trehalose or any combinations thereof. In certain embodiments, monosaccharides may include glucose, fructose, galactose or any combinations thereof. Intense sweeteners may include natural or artificial or combinations thereof. In certain embodiments, natural intense sweeteners may include but not be limited to: thaumatin, stevia, monk fruit (lou han gou), brazzein, curuclin, mabinlin, monatin, monellin, osladin, pentadin or combinations thereof. In certain embodiments, artificial intense sweeteners may include, but not be limited to: acesulfame potassium, advantame, alitame, aspartame, salts of aspartame acesulfame, sodium cyclamate, dulcin, glucin, neohesperidin, neotame, saccharin, sucralose or combinations thereof.

Where present, the sweetener may be a sugar alcohol, and preferably the sugar alcohol is in a crystallised or powdered form. The sugar alcohol may be selected from glycerol, arabitol, xylitol, erythritol, sorbitol, maltitol, mannitol, lactitol, isomalt, hydrogenated starch hydrolysates or combinations thereof.

The biodegradable composition may include a sweetener (such as a sugar alcohol) in an amount of at least 10% wt/wt, such as at least 11% wt/wt, such as at least 11.5% wt/wt. The biodegradable composition may include a sweetener (such as a sugar alcohol) in an amount of no more than 20% wt/wt, such as no more than 18% wt/wt, such as no more than 17% wt/wt. The biodegradable composition may include a sweetener (such as a sugar alcohol) in an amount of 10%-20% wt/wt, such as 11-18% wt/wt, such as 11.5- 17% wt/wt.

The invention provides a process for forming the container (such as the cup), including the step of baking the biodegradable composition in a suitable predetermined shape. The predetermined shape may be provided by a mould.

The invention provides a mould assembly for moulding the biodegradable composition of the invention, the mould assembly including: i) a core tool, and ii) a cavity tool so that a void is formed between a portion of the core tool and a portion of the cavity tool when the core tool and cavity tool are assembled into the mould assembly, wherein when the void is loaded with a mixture that includes water for moulding the core tool is in a first position proximate to the cavity, and wherein when heat is provided to the mould assembly for a time and under conditions such that at least a portion of the water in the mixture transitions to steam the core tool is configured to move to a second position more distant from the cavity tool than the first position so that at least a portion of the steam can escape from the void before the cavity tool and the core tool return to substantially the first position.

It will be appreciated that in the field of injection moulding, for example, the term "core tool" is typically used in relation to a so-called 'male' component, and the term "cavity tool" is typically used in relation to a so-called 'female' component, such that the tools engage to create a void corresponding to the dimensions of the component that is being moulded.

The mould may be used to form a cup and/or lid.

In some embodiments the core tool includes a flange that projects laterally outward from the centre of the core so as to abut a rim of the cavity tool so as to substantially seal the mould assembly. The flange may be provided with a skirt to at least partially surround the rim of the cavity tool.

In some embodiments the mould assembly may include a cap tool which may fasten to the core tool to provide a flange that projects laterally outward from the centre of the core so as to abut a rim of the cavity tool so as to substantially seal the mould assembly. The flange may be provided with a skirt to at least partially surround the rim of the cavity tool.

The mould assembly of the invention may also include a number of regions to facilitate the escape of steam, preferably without concomitant escape of the biodegradable composition that is intended to remain within the mould assembly. Examples of such regions include interstices which may variously be referred to as galleries, indents, depressions, channels, rebates, part lines. In each case it will be appreciated that gaseous steam is generally more easily removed through small spaces than the remaining solid or semi-solid biodegradable composition primarily because of the higher viscosity of the solid or semisolid material as opposed to steam. The use of galleries (which include rebated regions having a rectangular shape, for example) is especially preferred, and as used herein the term "galleries" is particularly used to describe interstices that become exposed upon the movement of the core tool from the first position to the second position, such that the galleries provide fluidic communication between the space occupied by the biodegradable composition being moulded and the environment external to the mould assembly such that steam may escape (be vented).

The movement of the core from the first position to the second position is a particularly advantageous aspect of the present invention and may be described variously as jogging, shuttling, bumping, and the like. In any case, the intended function is to allow steam to escape (primarily to avoid damage to the integrity of the biodegradable composition being baked - such as through cracking or pinholing) while still applying sufficient force on the biodegradable composition during baking such that it is produced in the desired space provided by the mould assembly. Preferably the mould is provided with relatively little resistance to this jogging process during the early phase of the baking to facilitate rapid removal of steam in this phase. Resistance may be provided merely by the weight of the core tool (and cap where used), or may be provided through a force external to the mould assembly such as pressure exerted on the core tool (and/or cap where used) by a ram or the like. In some embodiments the core tool may be biased to the first position under the influence of the weight of the core tool and/or a ram. In some embodiments the core tool may move from the first position to the second position due to pressure created as water transitions to steam, and/or the core tool may move from the first position to the second position due to the action of a retractor having the function to retract the core tool from the cavity, in which case it will typically be fastened to the core tool and/or cap.

Further aspects of the invention, which should be considered in all its novel aspects, will become apparent to those skilled in the art upon reading of the following description which provides at least one example of a practical application of the invention.

Brief Description of the Drawings

Figure 1 shows a cross sectional view through an exemplary cavity tool of the invention;

Figure 2 shows a cross sectional view through an exemplary core assembly tool of the invention;

Figure 3 shows a cross sectional view through an exemplary cap tool of the invention;

Figure 4 shows a cross sectional view through an exemplary mould assembly of the invention, formed from a cavity tool, core tool, and cap tool of the invention;

Figure 5 shows an isometric view of a cup lid formed of the biodegradable composition of the present invention;

Figure 6 shows a top view of a cup lid formed of the biodegradable composition of the present invention;

Figure 7 shows a cross-sectional view of a cup lid formed of the biodegradable composition of the present invention;

Figure 8 shows a side view of a cup lid formed of the biodegradable composition of the present invention.

Figure 9 shows an isometric view of the bottom of the core assembly tool of the fourth generation tool;

Figure 10 shows a top view of the core assembly tool of the fourth generation tool; Figure 11 shows an isometric view of a quarter piece of the core assembly tool of the fourth generation tool;

Figure 12 shows an isometric view of a quarter piece of the core assembly tool of the fourth generation tool;

Figure 13 shows a view of the lid cavity;

Figure 14 shows a view of the lid cavity;

Figure 15 shows a view of additional detail of a cavity quarter;

Figure 16 shows a view of the cross section of the closed lid tool assembly.

Detailed Description of the Invention

The present invention is directed, in part, towards an improved container and/or lid that is adapted to hold cold or hot liquids for a predetermined period of time without deforming. Reference will be made to a cup herein for convenience and by way of example only, however, it should be appreciated the terms "cup", "container" and "lid" may be used interchangeably and the present invention should not be seen as being limited to such.

The cup is comprised of a biodegradable composition that may be configured to biodegrade after a period of time. The biodegradable composition may include a filler material selected from flaxseed meal, rice bran, spent coffee grounds or combinations thereof, as well as other ingredients as will be described later.

Typically, the cup will be required to hold hot or cold liquids for a period of time in order for the consumer to finish the beverage. The cup of some embodiments of the present invention has been formulated to ensure that the cup is able to hold such liquids without deforming, but is also able to biodegrade in a timely manner once the cup has been discarded.

Preferably, the cup is adapted to hold hot or cold liquid for a period up to 24 hours without deforming. Typically, beverages freshly prepared onsite and sold in take away cups are consumed within an hour of preparation. Advantageously, the cup of some embodiments of the present invention may be able to hold such liquid for at least this period of time without deforming to allow the consumer to enough time to fully consume the beverage. It is desirable for consumers and businesses alike to ensure the beverage they are consuming or selling is not affected by premature deformation or degradation of the cup.

Once the beverage is consumed and the container is discarded, the discarded container may be adapted to substantially biodegrade within a certain timeframe, for example 24 months, of being subjected to composting conditions. More preferably, the container may be configured to fully biodegrade within 12 months of being subjected to composting conditions.

It should be appreciated by the person skilled in the art that the cup may also biodegrade over time in an environment without being subjected to composting conditions, however it is anticipated that compositing conditions may provide a quicker time frame for degradation. However, in some embodiments, advantageously the degradation of the cup will follow a similar profile as a food product due to the unique combination of ingredients/materials in the formulation of the cup.

Biodegradable Composition

In one aspect, the cup may be formed from a biodegradable composition comprising: a fat or oil; a filler; a matrix forming agent; and fibre.

The filler material may be selected from flaxseed meal or spent coffee grounds or rice bran or combinations thereof. The use of such materials is further discussed below.

Preferably the biodegradable composition does not include a polymer material such as polybutylene succinate (PBS), Poly Lactic Acid (PLA), Poly Lactide (CPLA), Poly Glycolic acid (PGA), Polyhydroxyalkanoates (PHA), Polyhydroxybutyrates (PHB), Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), Poly Adipate-co- Terephthalate (PBAT) and/or similar materials or combinations thereof.

It is noted that such polymers are known for their ability to biodegrade under certain conditions. Such polymers are typically included in cups and the like to provide a water-barrier layer and assist in claims that the product is biodegradable. However, it should be appreciated that the biodegradability of such polymers can only be achieved under certain conditions (typically industrial composting conditions which are not widely provided geographically, and which may make use of elevated temperatures not generally achievable under domestic composting conditions) and as such the product itself may not degrade for decades. In a further aspect, the biodegradable formulation of the cup is stable and does not impart any residue to the beverage or affect the taste of the beverage in anyway.

The biodegradable composition may advantageously be edible. For example, when the beverage contained in the container has been consumed by the consumer, the cup may be eaten by the consumer. This is achieved by formulating the cup from edible ingredients. Providing an edible cup allows the consumer to simply consume the cup once they have finished with the beverage, replacing the requirement to dispose of the cup. Alternatively, as the formulation is edible, it is anticipated that the cup will degrade naturally like a food product, under domestic composting conditions.

In one embodiment, the biodegradable composition includes: a fat or oil; a matrix forming agent; and a fibre, such as fibre selected from cereal, tuber, grain, seed or legume or combinations thereof. In some embodiments, the biodegradable composition may include a sweetener such as a sugar alcohol.

The principal matrix forming agent used in the present invention is preferably starch. In some embodiments, the starch may be selected from wheat starch, maize (corn) starch, potato starch, cassava (tapioca) starch, rice starch, glutinous rice starch and/or any combinations thereof. Minor adjustments of other ingredients in the composition may be compensated accordingly by adjusting the matrix forming agent, as the relative change of the principal matrix forming agent ingredient has been found to have less effect on the overall formulation. Preferably the starch is a non allergen containing starch.

Advantageously, water and oil may be used interchangeably as the 'wet' ingredients to suit the final product being produced. Both have a lubricating, softening or plasticising effect. At relatively high levels of both, for example above the noted ranges for these components stated below, the following properties are observed:

• the mix becomes a very soft dough which requires minimal force to press;

• a high shot size is required to fill the tool;

• baking ("bakeout") takes more time; and

• the product is generally oily.

On the other hand, at relatively low levels of both, for example below the noted ranges for these components stated below, the following properties are observed:

• the mix is crumbly and requires more force to make the press into final cup product; and

• where there is insufficient water to transfer heat or to gelatinise starch (where present) or create expansion, the final product will be dense and prone to crumble. Fillers such as flaxseed meal, coffee grounds and rice bran as may be used in the present invention are also interchangeable or may be used in combination. All three fillers function as solids that do not require any/substantial water for hydration. At relatively high levels of filler, starch when used as the principal matrix forming agent may be replaced, and the matrix will generally have insufficient consistency causing the cup to crumble. At relatively low levels of filler, more water may be required in order to hydrate the starch (when used) which would typically be needed to replace it. Such additional water will then typically need to be removed during baking ("bakeout"). Again, this will generally require a larger shot size, longer bakeout and cause excessive shrinkage.

Spent coffee grounds (referred to herein as "SCG") typically have residual moisture in them and will generally need to be subjected to a dehydration step before use. Preferably, the SCG should be standardised to between 5-10% moisture w/w.

In some embodiments, the filler (such as SCG, flaxseed meal, and/or rice bran) and any other coarse ingredients may be ground together to produce a uniform particle size, this helps facilitate consistency in the dry blend as well as flow during pressing to produce fine, homogenous cells during subsequent expansion of the wall and changes the perceived texture of the finished cup product.

The inventors prepared a number of formulations, using a number of fillers and matrix forming agents at varying weight ranges. Each were found to provide varying properties to the final biodegradable composition. The nature of each ingredient and its intended function in the biodegradable composition is discussed in further detail below.

Fat / Oil

Where present, the fat or oil may have a number of functions within the biodegradable composition. For example, it can be used as a water barrier, a release agent, a plasticiser of the dough, a flavouring element and/or provide organoleptic properties.

Where present, the fat or oil may be a vegetable oil. Preferably, the vegetable oil may be selected from soybean, rapeseed, rice bran, canola, sunflower, safflower, peanut, cottonseed, coconut, palm or any combinations thereof. Preferably the fat or oil is a non-allergen containing fat or oil.

The biodegradable composition may include a fat or oil in amount from 5%-20% wt/wt of the total composition, preferably 5-10% wt/wt, such as 7-9% wt/wt. It will be appreciated by the person skilled in the art that the choice of fat or oil may be varied according to the preferred formulation to be produced. Factors such as cost, shelf life and natural antioxidant content may be considered when preparing the final biodegradable composition. While ingredient cost is generally important, when manufacturing at scale ingredient cost becomes a less significant driver of overall cost. Particularly where the choice of ingredient due to an intrinsic characteristic can impart an extrinsic benefit such as extending shelf life.

In general, the more fat or oil in the biodegradable formulation, the better the water barrier properties. Physically preventing or slowing down water migration into the hydrophilic ingredients (other dry matrix forming agents) is an advantage when the cup is being used. For example, this retardation of water migration may increase the swelling time of these ingredients and increases the time to softening/deforming.

Advantageously, the fat or oil will generally assist with releasing the cup mass from the equipment surfaces during manufacture, particularly when used at higher levels. Alternatively, or in addition to using a higher level of fat or oil, the tool surfaces may be provided with a high polish to assist with release of the cup mass.

Still further, it is believed that the fat or oil in the formulation may play an advantageous role in facilitating the formation of an emulsion during preparation. Such an emulsion is believed to facilitate the formation of air or steam cells whose walls may have plasticity which may help to facilitate the development of an expanded wall section. Without wishing to be bound by theory, it is believed that too little fat or oil and the composition may preclude the ability to form structure(s) capable of trapping air or steam, resulting in a final product that is dense, brittle and crumbles.

The addition of fat or oil is believed to also advantageously provide an organoleptic experience associated with eating a cup of the present invention. Without wishing to be bound by theory, when a fat or oil is not used in sufficient quantity and it is desired that the cup is to be consumed by the user, apart from being brittle and crumbly the cup would seem dry to the consumer, especially where it has not come into contact with beverage.

Although the addition of fat or oil generally provides a positive contribution, it has been noted by the inventors that the upper level of use is limited by a number of drawbacks, most notably the finished cup will be oily or greasy to the touch. For example: when contacted with a piece of paper (such as A4 photocopy paper) the cup will leave a stain on that paper; and oil may appear on the surface of the beverage.

Furthermore, at high levels, fat or oil becomes a significant heat conductor. It has been observed by the inventors that it may be due to the following two reasons:

• First, excess fat or oil is not chemically bound or physically constrained within the matrix of the finished product and is free to flow. This mobility facilitates direct heat conduction through the cup wall and provides a wetted surface between the cup and the fingers of the consumer, further promoting conduction; and

• Second the cup wall appears to be more dense than it would otherwise be with a lower level of fat or oil. Some or many of the air or steam cells was found to contain oil, which is believed to be a better heat conductor than the air or steam that was intended.

Still further, free fat or oil, by nature, has a tendency towards auto-oxidation. The mono-, di- and polyunsaturated fatty acid esters that make up the fat or oil molecule may degrade into (for example) fatty acids, by reaction with air, moisture and/or other materials. The rate of degradation is dependent on temperature, time, light (photo oxidation), water and catalysts (trace metal ions, metalloproteins and inorganic salts). This process may proceed to the point that degradation products become unpalatable. This is commonly known as rancidity and is undesirable to have in the final product.

On the other hand, some fats or oils have higher levels of natural antioxidants and are somewhat more resistant to rancidity. These antioxidants include, carotenes, flavonoids, polyphenols, tocopherols and tocotrienols. Rice Bran Oil contains elevated levels of tocopherols, tocotrienols and the polyphenol/sterol group of esters known as Y-oryzanol (Gamma oryzanol) and is one of the more stable vegetable oils. The use of such fats or oils that have an inherent resistance to rancidity is preferred.

Rice as harvested may be referred to as paddy where the kernel is fully sealed by the rice hull. The hull is removed to yield brown rice, in the first milling operation. This reveals the brown bran layer. The bran layer is removed from the rice kernel to yield white rice in the second milling operation. The separated brown layer in this stage is called rice bran. The amount of rice bran is typically 8-12% of the total weight of brown rice.

The major components of rice bran are approximately 12-22 % oil, 11-17 % protein, 6-14 % fibre, 10-15 % moisture, and 8-17 % ash. Rice bran also is rich in a variety of vitamins and minerals. These include thiamin, niacin, vitamin E, phosphorus, potassium, magnesium, and silicon. The lipid in rice bran contains oleic acid (38.4 %), linoleic acid (34.4 %), and linolenic acid (2.2 %) as unsaturated fatty acids, and palmitic (21.5 %) and stearic acid (2.9 %) as saturated fatty acids. The unsaponifiable fraction of rice bran oil (4.2 %) includes tocopherols and tocotrienols (0.08 %), y-oryzanol (1.6 %), and squalene (0.32 %). High levels of tocopherols, tocotrienols and y-oryzanol in rice bran are important in protection against oxidation of rice bran oil. Y-Oryzanol also possesses antioxidant activity in stabilizing other lipids.

Matrix forming agent

The matrix forming agent may be the principal ingredient by weight in the biodegradable composition. In other words the matrix forming agent may provide the highest weight percentage of any component in the composition.

Wheat flour may be used, since advantageously it is a recognisable, cheap, available and functional ingredient. In particular, it has an ability to form a long, cohesive, tensile dough, suitable for flowing into and forming shapes that are consistent with the outcome of this application, which can then be baked. The characteristics of wheat flour, as against wheat starch, are to a larger extent determined by its gluten content over other characteristics such as cultivar, starch granule size, amylose to amylopectin ratio, etc. However, the protein gluten in wheat starch is a common allergen. The inventors acknowledge the preference for an allergen free approach to development, particularly when preparing an edible formulation, wherein wheat flour (containing gluten) may otherwise be the flour of choice. For that reason, the preferred matrix forming agent is gluten free starch. However, it should be appreciated that flour may also be used interchangeably or in combination with gluten free starch.

Flour may be distinguished from starch by the method of extraction. Flour is typically characterised by the dry, mechanical separation of germ from endosperm and seed coating or bran. This effectively removes the fat-containing germ and bran from the endosperm, which would otherwise oxidise causing rancidity and reduce the shelf life of flour. Most of the other components of the endosperm are retained, including the protein component which, in wheat, ranges from 8 -15%. In turn, gluten is the major protein group within wheat protein. It is gluten that is largely responsible for the structural properties of wheat flour that make it so useful in baked cereal products. The strength of wheat flour is measured by its protein content.

Starch is typically separated in a relatively complex wet milling system that also separates germ, bran and gluten from endosperm. Starch is therefore more refined than flour, containing little or no protein. Starch occurs naturally as discrete particles (granules). General properties of selected starches and their pastes are given in Table 1. Granules vary in average size and shape. Within these granules there are two arrangements of repeating glucose units: linear and branched.

Amylose is essentially a linear chain of (1-4) linked a-D-glucose units, while Amylopectin is a very large, highly branched molecule with additional (1-6) linked a-D-glucose units. Starch with a high proportion of amylopectin is also known as waxy starch. As a result, it can be expected that the ratio of amylose to amylopectin within the starch granule will give properties that characterise the behaviour of the source starch.

Table 1. General Properties of Some Starch Granules and Their Pastes

Gluten aside, when attempting to substitute one starch for another, it will be appreciated by the person skilled in the art that consideration should be given to the properties of the substitute starch. In this case it can be seen from Table 1 that both common corn starch and tapioca starch appear to be favourable substitutes for wheat starch in a like-for-like application. Of the two, the paste rheology for both wheat starch and corn starch is 'short', which suggests that this may be a good match on the face of it. When factoring in the influence that gluten has in wheat flour, wheat flour has a very long and extensible characteristic, more consistent with the paste rheology of tapioca starch and it is for this reason that tapioca may be preferred if seeking an allergen free substitute. In a further consideration of the effect of gluten in wheat flour, the very extensible and cohesive nature of glutinous rice starch is a useful attribute. Glutinous rice starch has very little protein. The rheology of glutinous rice starch is not related to the presence of gluten protein but to its high amylopectin content. In addition, the almost non existent amylose content and very high amylopectin content of glutinous rice starch can be expected to make it more resistant to retrogradation and therefore staling, than both corn and tapioca starches and wheat starch or flour.

Advantageously, gelatinisation of the starch (when used) is believed to "glue" the other ingredients together. To that end, tapioca starch may be preferred due to its long cohesive paste characteristics which make it less prone to shrinkage during the moulding process as water is removed from the final product.

Glutinous rice starch may be preferred due to its very long cohesive paste characteristics which also make it less prone to shrinkage during the moulding process as water is removed from the final product.

Preferably, the biodegradable composition may include a matrix forming agent in an amount of 10% - 45% wt/wt. Still more preferably, the matrix forming agent is included in the composition in an amount of 25% - 45% wt/wt, such as in an amount of 26-40% wt/wt.

It has been observed by the inventors that, at low levels of starch, for example less than 10% wt/wt there is not enough matrix forming agent material to form a continuous matrix capable of carrying other ingredients. In such cases, the behaviour of the cup will tend toward the typical characteristic of the next most dominant ingredient.

The proportion of water to starch may be adapted to maintain suitable conditions for gelatinisation during preparation, such as during baking. Without wishing to be bound by theory, the water to starch ratio is believed to play an important role in developing the properties of the cup product, and the inventors have observed that with high starch levels in the composition, there is a correspondingly high amount of water required to gelatinise the starch. At least part of this water generally needs to be removed during the production stage of the cup, such as during bake out, and the removal of a large amount of water generally leads to excessive shrinkage during bake out which in turn causes fracturing of or pin holing in the finished cup wall matrix. Sweetener

A sweetener may be included in the biodegradable composition. The sweetener is generally used to provide sweetness to the final cup formulation, which may be desirable in embodiments where the formulation is edible.

Sweeteners may be selected from sugars, intense sweeteners, sugar alcohols or any combinations thereof. Sugars may include disaccharides and monosaccharides or any combinations thereof. In certain embodiments, disaccharides may include sucrose, lactose, maltose, isomaltose, trehalose or any combinations thereof. In certain embodiments, monosaccharides may include glucose, fructose, galactose or any combinations thereof. Intense sweeteners may include natural or artificial or combinations thereof. In certain embodiments, natural intense sweeteners may include but not be limited to thaumatin, stevia, monk fruit (lou han gou), brazzein, curuclin, mabinlin, monatin, monellin, osladin, pentadin or combinations thereof. In certain embodiments, artificial intense sweeteners may include, but not be limited to acesulfame potassium, advantame, alitame, aspartame, salts of aspartame acesulfame, sodium cyclamate, dulcin, glucin, neohesperidin, neotame, saccharin, sucralose or combinations thereof.

Sugar alcohol sweeteners are distinguished from intense sweeteners. In a manner similar to sugar, they provide bulk rather than intensity of sweetness. Useful sugar alcohol sweeteners that may be used in the present invention are given in Table 2.

Table 2. Energy factors and relative sweetness for specific components Sugar alcohol sweeteners are used in preference to sugar to reduce the energy contribution in the final product. For comparison, the energy factor for sugar is 17 kJ/g. Advantageously, as compared with sugar, sugar alcohols are not metabolized by oral bacteria and so they don't contribute to tooth decay. Furthermore, sugar alcohols do not brown or caramelise when heated.

Furthermore, the inventors have observed that it is advantageous to choose a sugar substitute for use in the present invention that:

• is a solid not a liquid - preferably in crystalline or powdered form;

• has a low energy factor;

• has a high relative sweetness;

• has a sweetness profile similar to sugar; and

• is relatively low cost.

Erythritol is the preferred sugar substitute for use in the present invention for these reasons. Like sugar, erythritol provides additional bulk and behaves in a similar manner, both in solution and in the absence of water when incorporated into the composition of the present invention. Additionally, it has been observed to set on cooling after the composition has been subjected to the manufacturing process (such as baking), providing firmness and rigidity to the cup wall.

The biodegradable composition may include a sweetener (such as a sugar alcohol) in an amount of 10%- 20% wt/wt, such as 11-18% wt/wt, such as 11.5-17% wt/wt.

In addition to sweetness, some sugar alcohols can produce a noticeable cooling sensation in the mouth when used in high concentrations. This happens, for example, with the crystalline phase of sorbitol, erythritol, xylitol, mannitol, lactitol and maltitol. It is believed that the cooling sensation is due to the dissolution of the sugar alcohol being an endothermic (heat-absorbing) reaction, one with a strong positive heat of solution. Erythritol has a strong cooling effect.

The upper limit of sweetener in the composition may be determined in part by the cooling that would be imparted to a hot beverage in the cup at high levels of use as erythritol slowly comes into solution through contact with the beverage.

It addition, it should be noted that high levels of soluble sweetener (e.g. at levels above 20% wt/wt) may adversely affect cup wall strength and rigidity as they dissolve into the beverage. As such, the person skilled in the art would take this into consideration when formulating a suitable composition in accordance with the present invention. Despite a preference for using solid (such as crystalline) sugar alcohols, it has been found by the inventors that the addition of glycerol to the formulation provides additional control over the softness and flexibility of the container and/or lid over the life of the product, especially when used in conjunction with suitable packaging to control moisture loss.

Glycerol is one of the few sugar alcohols which does not have a crystalline form. It is cheap, safe and of an agreeable flavour when used in low amounts. It does not set on removal of water during bake out as the crystalline alternatives do. It remains a liquid and in so doing retains a certain amount of water in the product thereby exerting a softening and plasticising effect in the manner of a humectant. This is a useful attribute where controlled deformation of the container and/or lid is required such as in the case where a lid must expand slightly to clip over its container as in the case of a coffee cup and/or lid wherein the lid clips over the lip of the coffee cup to form a contiguous and largely water tight seal with the cup.

Glycerol may be added in the range of 0-6% wt/wt, preferably in the range 2-3% wt/wt. At higher levels of glycerol, the container may become too soft to be useful.

Fibre

Fibre in the present invention refers, in the first instance, to the crude, insoluble but edible components of plant foods, such as legumes, whole grains and cereals, vegetables, fruits, and nuts or seeds. In the case of cereal grains this crude fibre is often referred to as bran.

Sources of bran include: oats, wheat, barley, rye, rice, corn, flaxseed (linseed), sorghum, spelt, millet, peas, chickpeas, tef, psyllium or combinations thereof.

In the second instance, fibre refers to the soluble polysaccharides produced both synthetically and naturally, including by many plants. Polydextrose is an example of the former and inulin an example of the latter.

Fibre has been used as a bulk ingredient, which may allow for the partial replacement of starch. It has been observed by the inventors that the use of fibre has the advantage of reducing shrinkage during processing as fibre does not require water for hydration. Additionally, the use of fibre may also be a relatively cheap source of bulking ingredient, thereby reducing costs for manufacturing. Where a small amount of fibre is used, often a more expensive ingredient/substituent will replace it, which may increase the cost of production.

The fibre ingredient in the first instance is essentially insoluble in water, and it should ideally be dispersed homogenously throughout the 'dry' mix. It has little or no capacity to bind to itself and it becomes embedded in the starch matrix where starch is used. It will be appreciated by the person skilled in the art that the upper limit of use the fibre ingredient is determined by the ability of the other components in the composition (particularly the starch, where present) to maintain a continuous matrix.

In the second instance, soluble fibre is also used as a bulking agent but it does have the ability to bind water and to bind to itself. Nevertheless, soluble fibre should still be dispersed homogenously throughout the 'dry' mix. It is capable of partially replacing some or all of the sugar or sugar substitute, starch or fat components and may provide a limited degree of sweetness. Without wishing to be bound by theory, it is believed that, when used, soluble fibre may become part of the continuous matrix of the present invention.

In some embodiments fibre may be the principal ingredient and may be used in combinations of soluble and insoluble.

In a preferred embodiment, the biodegradable composition may include fibre in an amount of 10% - 40% wt/wt. Preferably, the fibre is included in the composition in an amount of 25% - 35% wt/wt.

In a preferred embodiment, the fibre source used in the present invention may be allergen free. It may also be preferable to use an ingredient that is sourced close to the site of manufacture of any product, for example it may be preferable to use an ingredient made locally in New Zealand. For these reasons flaxseed (linseed) meal has been identified as a preferred fibre ingredient. In this case flaxseed meal differs from bran in that it is the seed material left after oil is pressed out. It still contains germ, bran and endosperm but with reduced oil content.

The residual oil in flaxseed meal makes a contribution to the overall oil content of the finished product. Like many other oils, flaxseed oil is a triglyceride. It is characterised by a high proportion (generally 52-55%) of a-linoleic fatty acid which is easily oxidised, and rapidly becomes rancid, with an unpleasant odour. In the case of flaxseed as a source of fibre, this predisposition to rancidity serves to set an upper limit on its use in the formulation of the present invention since a predisposition to developing rancidity rapidly is not preferred. It will be appreciated that, although flaxseed may be used in the present composition for its insoluble fibre content, it does contain a proportion of soluble fibre. This soluble fibre is present in the form of mucilage located in the outer layers of the seed, which is highly unusual among oil seeds. This mucilage is not well characterised in the current literature but is understood to possesses similar properties to that of guar gum, a known stabiliser. Gums of this nature, naturally present in ingredients, make a useful contribution to improved extensibility of the biodegradable composition of the present invention. Other non-oil seeds such as chia which have similar polysaccharide mucilage components may also be similarly used in the present invention.

Nevertheless, it will be recognised by one skilled in the art, that other sources of fibre, with or without mucilage, such as rice bran, can make useful contributions to the present invention, particularly when used in combination with starches having a strong, extensible characteristic, such as glutinous rice starch.

Spent Coffee Grounds (SCG)

SCG is a by-product from making coffee. The average weight of SCG is about 75% that of the original coffee bean. In 2018, the annual quantity of SCG was reported to be about 6 million tons worldwide. The disposal of SCG is problematic and may be viewed as a source of environmental pollution.

The biodegradable composition may include SCG in an amount of 4% - 20% wt/wt. Preferably, SCG is included in the composition in an amount of 8% - 12% wt/wt.

SCG contains large amounts of organic compounds, such as fatty acids, amino acids, polyphenols, minerals, polysaccharides, and lignin. The richness of polyphenolics such as chlorogenic acid, caffeic acid, gallic acid, ferulic acid, and cinnamic acid impart a reasonably significant free radical scavenging capability to SCG. This antioxidant capability is an unexpected advantage provided by the biodegradable composition of the present invention, particularly when using sensitive components such as the a-linoleic fatty acid present in flaxseed oil.

Surprisingly, the inventors have found that SCG acts in a similar manner to fibre in its bulking function in the present invention and therefore in its ability to reduce shrinkage during production of the cup.

SCG may be practically sourced from food service operations. In this case the majority of SCG may be of Arabica origin (Coffea arabica), however it will be appreciated that other sources and origins may be used with the present invention. Typically, SCG will carry a relatively high proportion of residual , and often soluble, organic compounds, when sourced from food service operations. As a result, its use will impart some flavour and aroma to the finished cup. Aroma and flavour may be reduced by subjecting the SCG to a washing process prior to drying.

Alternatively, SCG from commercial coffee extraction may be more likely to be of Robusta origin (Coffea canephora (syn. Coffea robusta)). The moisture content from such operations is likely to be relatively high and is likely to need reduction and standardisation prior to use in the present formulation. The degree of coffee extraction is significantly higher in commercial coffee extraction so the level of residual organic compounds will typically be much lower in the spent grounds sourced from commercial coffee extraction. Although coffee flavour and aroma are still present in the finished cup made with SCG from Robusta, it has been observed by the inventors to be more neutral.

The use of SCG provides numerous environmental and social benefits. The use of a by-product such as SCG which would otherwise be discarded can be reused in an economic and environmentally friendly manner and provides a viable alternative to consumers and businesses alike.

Other forms of coffee grounds may be used, for example non-spent coffee grounds. This may provide some of the benefits of spent coffee grounds and may be easier to source, although other advantages of using a waste stream such as SCG may not be realised.

Water

Water is typically the only ingredient that is substantially removed during the production (such as baking) phase. Its principal function is to hydrate and/or solubilise those components capable of hydration and/or solubilisation, such as starch and/or sweetener (such as erythritol), where used. When used with starch it will be appreciated that water facilitates gelatinisation of the starch and formation of a continuous matrix incorporating other ingredients.

Without wishing to be bound by theory, during preparation, water has the dual function of facilitating even heat transfer into and throughout the mixture and the equipment, at the same time expanding in the form of steam to create cells within the matrix. The formation of cells in the cold cup wall matrix creates an expanded wall section which provides a thermal barrier to heat loss from the hot beverage. This is turn reduces softening of the cup wall, leading to a more robust product, especially when the contents of the cup are still hot.

The total amount of water included in the biodegradable composition will vary, and will include the sum of the free water present in all of the ingredients. Water acts as an effective lubricant or softener. At the lower limit, heat transfer into the mix is slow, flow within the tool is reduced and considerable force is required to press the tool. At the higher limit heat transfer and flow is faster, less force is required but a lot more water must be removed during bake out. Additionally, a larger dose of mix must be added to compensate for the water to be removed, since the volume of the tool may typically be fixed and the tool must be full with the remaining mix at the end of the cycle for a successful shot. This requires a longer holding time during bake out. Since cycle time has a significant influence on plant economics, a smaller shot size and reduced cycle time is preferable. On that basis it is generally preferred to use as small a quantity of water as possible to still provide its desired functional benefits, such as gelatinisation where that is desired.

Preferably the biodegradable composition that is mixed together for moulding, such as baking, will include an aliquot of water of up to 20% wt/wt of the biodegradable composition; such as 5-15% wt/wt of the biodegradable composition; such as 8 to 11% wt/wt of the biodegradable composition. In general, apart from water used in the gelatinisation and/or hydration of other components in the biodegradable composition, the aliquot of water added is substantially removed during the moulding/baking process (which is a preferred method of forming the composition into a product suitable for the end user).

Examples

This present invention will now be described by reference to the following biodegradable compositions (formulations) prepared for use in a container, cup and/or lid. However, such examples should not be seen as limiting on the scope of the present invention.

Example 1 - Formulations

Example 2 - Formulations

Example 3 - Formulations (Savoury - without sweetener)

* The seed mix takes the place of the crude fibre here. These are basically crushed seeds that are similar in form and function to flaxseed meal, SCG or Rice Bran.

Example 4 - Formulations Example 5 - Formulations

Example 6 - Formulations

Example 6 - Formulations

T1

Method of Manufacture

Forming the container from or of the biodegradable composition may occur using any suitable container manufacturing technique as may be apparent to one skilled in the art. For example, it will be appreciated that scale may influence a suitable method of manufacture.

On a batch scale, although not strictly required, 'wet' and 'dry' ingredients may be compounded separately for convenience. The ingredients may then be combined in a mixer immediately prior to mixing. The particular order of addition/combination may not be important.

A method of manufacturing a cup according to one aspect of the present invention will now be described below. Embodiments of the invention should not be seen as being limited to such a method in any way.

Step a) measure out and mix all 'dry' ingredients (matrix forming agent, fibre, sweetener, and SCG) together into a homogenous mixture.

Step b) separately measure the 'wet' ingredients (oil and water) into a mixing bowl.

Step c) add the dry mix from step a) into the wet mix and blend thoroughly to form a mixture. The mixture may range from a very soft plastic dough, with medium extensibility to a semi-dry, agglomerated crumble, dependent on ingredient proportions. The exemplary formulation of example 1 given above produces a moist crumb having flow properties that allow it to be accurately portioned by weight.

Step d) the mixture is then dosed into and pressed into heatable moulds shaped in the form of a cup(s) and lid(s); and Step e) The heatable moulds are heated up to a temperate of between 120 - 160°C for a predetermined period to bake the mixture. Baking the mixture gelatinises the starch, hardens the dough, and removes excess water from the mixture to produce the final cup product.

It will be appreciated that the time and temperature of the baking step can be adjusted as required depending on the final formulation and the amount of excess water to be removed.

On a large scale, a similar process for compounding the ingredients described above may be followed, however the 'wet' and 'dry' ingredients may be continuously mixed in a fluidising mixer of the type commonly encountered in food production using extrusion, known as a pre-conditioner. Dry/powdered ingredients are individually metered into the pre-conditioner and fluidised by counter rotating paddles or blades while wet ingredients are simultaneously metered and sprayed into the fluidised powders. Intimately blended, fine particles flow out of the pre-conditioner onto the next stage.

While reference has been made to an extrusion method for mixing the components, this should not be seen as being limited on the scope present invention. It will be appreciated by the person skilled in the art that other methods for the manufacture of the mixture may be used.

Method of Manufacture - tooling

It will be understood that in the field of injection moulding, the mould (and tools) may be described using the terms 'core' and 'cavity'. As used herein, the terms core and cavity take their normal meaning - namely that the core is the so-called 'male' part which forms the internal shape of the moulding; and the cavity is the so-called 'female' part which forms the external shape of the moulding.

Early trials ("first generation tooling") used a partially cooked pancake, formed from the biodegradable composition, which was then sandwiched between two hot moulds and formed into the shape of a cup as the moulds were pressed together. A core, the shape of a cup was mounted in a press as if the cup was upside down. The partially cooked pancake was placed over the core and a cavity substantially the same complimentary shape as the core was pressed down onto the core and pancake. Both core and cavity were pre-heated.

The cavity in this arrangement was split vertically. The two pieces of the cavity would descend and come together simultaneously. Once closed they were pressed the last few millimeters onto the core. Once the cup had been baked the core cavity would rise and part, leaving the partially formed cup on the core. This approach had some merit since the partially cooked pancake was less prone to flashing through the cavity part line.

During development of the first generation tooling, the limitations of this approach became clear. While the method was capable of being used to form a container, it was difficult to ensure even distribution of pancake through the tools because it was prone to tear randomly. This method produced partial cups with random amounts of fill or completeness. It was also difficult to remove the hot, partially formed cup from the core. As such, while this method was suitable for isolated instances of production, it was less likely to be useful when scaled to significant quantities.

From this understanding of the tool and the biodegradable composition formulation it was clear that the tool arrangement could be turned over such that the cavities would be on the bottom facing up in the manner of a cup, while the core could face down. The mixture could be dosed into the closed cavities without any pre-baking and the core pressed into the cavities to form the cup. The cavities were to be latched together. This approach is referred to herein as the "second generation tooling".

Once the cup had been sufficiently baked the core was removed and the cavities unlatched and parted to release the formed cup.

Additionally, the core was made in two parts: a bottom part and a top part, held together by a hollow cap screw. The hollow cap screw allows for the provision for air to be injected both down the inside and outside of the cap screw. Air traveling down the outside and through the part line of the two core pieces facilitates release of the baked out cup from the core. In addition, air traveling down the centre of the cap screw to a valve added to the bottom of the core piece provides further ingress of air to facilitate release of the baked out cup from the core.

This second generation tooling method provided a substantial improvement over the first generation tooling method described above. The cavity could be more fully and evenly filled. Opening the cavities horizontally allowed access to the baked cup.

One of the drawbacks with this arrangement, however, was that sufficient water had to be added to the mixture in order to facilitate even flow throughout the tool. Because the cavity tools were not heavily clamped by the latches, hot mixture could flash through the part lines of the cavities due to the substantial pressure developed by water converting to steam. Flashing would need to be removed from the finished cup and preferably flashing should be avoided both for the extra operation that would be required to remove it and for the sake of a good quality appearance. This flashing also occasioned the cup to stick to the cavities and tear the cup as the cavities were parted while the cup was still hot and soft.

The extra water required to achieve good flow throughout the tool also had to be removed with longer baking time. Preferably the baking time should be minimized since cycle time can be expected to have a major impact on the product economics.

Water also has to be vented from the within the tools. Since this water forms part of the totality of mixture added to the tools, in order to maintain the correct amount of mixture in the tool after baking and water removal, more mixture must be added to the tools than is left after baking. If this is not correctly accounted for one of three things will happen: It was found, either the tool will be over full and cannot close fully after bakeout. This is likely to further induce flashing, or, in the second case, the product will not be fully baked out, or in the third case, the tool will be under full, following bake out. In the latter case, it was found that the mixture will shrink to less than the volume of the cavity as it bakes water out. This shrinkage will result in substantial voids or fractures in the structure of the cup at worst or pinholes at best, although this mechanism wasn't understood as the cause of fractures and pinholes at the time. This was confounded to an extent by the variable amount of mixture being lost through flashing through the part lines. Additionally, it was found that the finished cup would occasionally shrink onto and stick to the core, from which it was difficult to remove in one piece.

The approach taken above contemplated a solid wall section throughout the cup. A solid wall has some disadvantages for use. A solid wall is relatively thin in relation to the amount of material used. This has three important implications: A thin wall section is relatively mechanically weak, in the second instance it has a relatively high rate of heat transfer and in the third instance it has a relatively high rate of softening as water has a relatively short distance to penetrate over time.

From trials of the second generation tooling it became clear that the removal of water from the mixture during bakeout might be used advantageously to create an expanded wall cross section throughout the cup. Furthermore it was found that a high degree of polish on the tool contact surfaces, together with the correct use of release agents in the mixture meant the baked out cup would release consistently from both cavity and core, whereupon the finished cup could be extracted from the tool set with relative ease.

From this understanding of the second generation tooling, and the biodegradable composition formulations that had been developed, a "third generation tooling" was developed. It was speculated that the cavity could be made in one piece. Furthermore, the specific volume of the baked out cup could be increased to allow for a thicker wall section and an expanded wall section could be employed. A valve could be added to the bottom of the cavity in a similar manner to the valve in the bottom of the core, to facilitate release and extraction of the finished cup from the cavity using air if necessary.

We refer now to figures 1 to 4 of the third generation tooling, which is represented in cross section.

The third generation tool set is substantially provided in three parts: The cavity tool (1) (as shown in Figure 1), the core assembly tool (2) (as shown in Figure 2) and the cap tool (3) (as shown in Figure 3).

The cavity (4) in cavity tool (1) substantially defines the outer bounds of the desired cup wall, the shape of which is arbitrary and should not be seen as limiting. The shape shown in cross section in Figure 1 is intended to provide a substantially frustoconical shaped cup and so, in cross section, the side walls diverge in the direction of the intended cup opening. Galleries (5) are provided to facilitate the controlled escape of steam but without the escape of biodegradable composition. The intention being to enable the core assembly tool (2) to rise (i.e. separate in relation to the cavity tool (1)) under the pressure of generated steam, to allow the steam to preferentially escape as the bottom of the galleries (5) are cleared by the core assembly tool (2) while any rising mixture would be forced back into the cavity (4) as the core assembly (2) returned to a position closer to the cavity tool (1) having released built up steam. A reverse valve (6) is located in the bottom of the cavity with an attendant gallery (7) to the outside of the tool for the provision of air into the cavity (4) when desired. Provision may be made for a plurality of galleries (8) to accommodate temperature probes (not shown). Provision may also be made for a plurality of galleries (9) to accommodate heating cartridges.

The core assembly tool (2) substantially defines the inner bounds of the cup. The tool shown comprises an upper section (10) and a lower section (11). The upper section may have provision for a plurality of galleries to carry temperature probes (8) and heating cartridges (9), one each of which is shown in Figure 2. The lower section (11) may have provision for complimentary galleries to carry the heating cartridges, primarily to facilitate more even heating throughout the core assembly tool (2). The upper section (10) and the lower section (11) are held together with a cap screw (12) extending from the upper section (10) to the lower section (11). The cap screw (12) shown has axial and horizontal drillings (13) to allow the passage of air down both the centre and outside of the cap screw (12). Air down the outside of the cap screw (12) feeds to the part line which is identifiable as the interface between upper core section (10) and lower core section (11), while air down the inside of the cap screw (12) feeds valve (14) in the bottom of the lower core section (11). Because the cap screw maintains tension on the part line between upper core section (10) and lower core section (11), air can be successfully employed to help release the bottom of the finished cup from the core while preventing significant flashing of hot mixture into the part line during pressing. This is in part helped by the fact that at the position of the part line, mixture is moving tangentially across and not perpendicularly to or from the part line as it flows from the bottom of the cavity to the top.

Cap tool (3) is affixed to the top of upper section (10). Its inner edge is simultaneously circumferential with the top of the outer edge of both upper section (10) and cavity tool (1) thereby aligning core assembly tool (2) with the centre of cavity tool (1), which in turn allows for the final cup to be manufactured with symmetrical shape, including side walls of substantially equal thickness. Cap tool (3) contains a gallery (15) situated above the cap screw (12) and connected to the outside of the cap tool (3) for the provision of air to both the part line of the core assembly tool (2) and valve (14). Cap tool (3) has an opening (16) to allow for the egress of temperature probe (8) and heating element (9) cables mounted in the core assembly tool (2).

Turning now to the operation of the entire assembly, cap tool (3) and core assembly tool (2) are withdrawn from cavity tool (1). A quantity of biodegradable composition mixture is loaded into cavity (4) and the core assembly tool (2) and cap tool (3) are closed onto cavity tool (1) as shown in Figure 4. The biodegradable composition mixture is heated and flows throughout the remaining cavity space. Under appropriate conditions, steam is generated as the mixture bakes out. The evolution of steam causes pressure to build in the cavity which in turn causes core assembly tool (2) and cap tool (3) to rise as the force generated by the build up of pressure exceeds the weight of the core assembly tool (2) and cap tool (3), so that the steam galleries (5) become exposed allowing steam to escape while biodegradable composition mixture solids remain trapped in the cavity. Core tool (2) and cap tool (3) will return to a position more proximal the cavity tool (1) as steam is released. Several cycles of steam purging may occur before bake out is complete. Once bake out is substantially complete, core assembly tool (2) and cap tool (3) are withdrawn and the finished cup is extracted from the cavity.

Core assembly tool (2) and cavity tool (1) temperatures may be in the range 120 - 160 °C. Preferably they are in the range 130 - 150 °C.

It will be appreciated that the use of heating cartridges is one method of heating the core assembly tool (2) and in turn the biodegradable composition mixture in the cavity. Heating of the cavity for instance, may equally be achieved by making a straight sided, cylindrical cavity tool and utilising a heating band of the appropriate size and power. One skilled in the art could conceive of a number of ways to heat both core and cavity without deviating from the intent of the present invention which is functionally to bake the biodegradable composition mixture and in turn driving off excess water. For instance core or cavity may be heated by flame or radiant device given suitable design. However the inventors believe that the use of heating cartridges provides a scalable means of producing cups. Advantageously, the configuration of this third generation tool allows the cavity tool (1) to be mounted on a single axis gimbal wherein having withdrawn the core assembly tool (2), the cavity tool (1) can then be tilted to allow the finished cup to conveniently fall out of the cavity tool (1).

The inventors found that there is a relationship between the occurrence of fractures/pinholes and the shot size (volume of biodegradable composition mixture loaded into the cavity tool) and the water content of the biodegradable composition mixture. Fractures and pinholes typically arise when water is baked out of the mixture and there is insufficient mixture to fill the tool cavity.

The third generation tool forces the steam to only escape upwards and through the galleries (5) and only when the core assembly tool (2) is partially withdrawn to expose the galleries (5). As the pressure builds and overcomes the weight of the core assembly tool (2) and cap tool (3), a frequent 'jogging' of the core (2) up and down to release built up steam is observed. It was found that unless steam was released regularly, mixture would be ejected through the galleries (5) as the core jogged up. The frequency of jogging was observed to facilitate the more rapid release of steam at the beginning while the water content was high and the frequency reduced towards the end of the bake out as water content was depleted in the mixture.

The force required to compress the mixture in the present arrangement is inversely proportional to the amount of water in the biodegradable composition mixture - for example, less water requires greater compressive force. There are two advantages to having less water in the formulation. Overall shot size can be smaller and cycle time can be reduced. Reduction in cycle time has major economic implications for large scale production, although this would be expected to be offset to a small extent by the increased capital cost associated with the requirement for increased compressive force.

Following the learnings from this third generation tool and its operation, further improvements in the method of releasing steam were developed. It was speculated that both cavity tool (1) and core assembly tool (2) could be configured to facilitate the release of steam using a hybrid configuration wherein both cavity and core were each split vertically into four pieces. Respective quarters in each of the core and cavity would be suitably clamped together to present lines of escape for built up steam but not mixture. These developments led to a "fourth generation tooling" - specifically focused on improved lid and lid tool assembly designs.

We refer now to figures 5 to 8 of the fourth generation tool which show the form of a coffee cup lid formed from the biodegradable composition of the present invention. The heart shaped feature (38) evident in Figures 5 and 6 is an arbitrary shape and it will be clear to one skilled in the art that any useful shape may serve the purpose, at any height from and angle to the plane of the base of the disc without departing from the intent of the invention. It will also be clear this facet need not be plain in its surface texture. It may carry additional elements of a graphic nature or the like, for example: logos or text.

It will be appreciated by one skilled in the art that while the absolute shape of the lid is somewhat arbitrary, certain features for its successful function will be common to design. The form of the lid is substantially a modified disk (Figures 5 and 6), having raised features evident in the Z dimension as show in Figure 8.

Looking at Section A-A shown in Figure 7, the orientation of which is shown in Figure 8, it can be seen that a skirt (circled) is substantially formed in the shape of the modified disc. This skirt incorporates an undercut (15) which serves to provide a feature allowing the lid to roll over the lip of a cup and fasten the lid onto the cup forming a substantially contiguous and water tight seal.

Provision is made for an aperture (16; a "sipper") in the modified disc to allow the consumer to sip a beverage through the lid. Further provision is made for another aperture (17) in the modified disc to function as a "breather", allowing pressure within a cup sealed by the lid to equilibrate as a beverage is sipped from the cup.

Figure 9 shows an isometric view of the bottom of the core assembly tool. Figure 10 shows the top view of that core assembly tool. Figures 11 and 12 provide additional detail of a core section. Figures 13 and 14 provide views of the lid cavity. Figure 15 provides a view of additional detail of a cavity quarter and Figure 16 provides a view of the cross section of the closed lid tool assembly.

The core tool of Figure 9, substantially defines the inner bounds of the lid, and the tool has been sectioned into quarters. Provision is made to fasten each quarter to its successive neighbour, such as through use of a bolt (18). Provision is made on the core tool for a pin (19) in the shape of the sipper aperture (16) with sufficient length to pierce the corresponding sipper aperture (29) in the cavity. This pin may be split between its two respective quarters and therefore each half is integral to its respective quarter, or the pin may be a solid piece added to a like and common cavity milled into the two quarters. Likewise provision is made in the core tool for a pin (20) in the shape of the breather aperture (17) with sufficient length to pierce the corresponding aperture (30) in the cavity. Like the sipper pin (19) it may be split with each half being integral to its respective quarter or the pin may be a solid piece added to a like and common cavity milled into the two quarters. Each quarter of the core tool carries a guide pin (21) through the flange (38) of each piece. Each guide pin (21) is threaded (22) into the flange (38) of its corresponding quarter. Provision is made in the top of the core assembly for a plurality of galleries to take heating cartridges (23) and temperature probes (24).

While the faces of each quarter of the core assembly are tightly clamped together, galleries (25) are rebated into the face of each quarter to preferentially duct steam through the part lines. Additional drillings (26) and (27) in one of the quarters connect to the rebates (25) to vent steam to the outside of the tool. In the present embodiment drilling (27) is plugged at the surface of the tool. An additional drilling (28) connects drilling (27) to the circumferential perimeter of the quarter. This arrangement not only allows steam to escape but air can also be injected into the drillings and galleries to facilitate the preferential release of the finished cup from the core tool during operation.

The cavity in the cavity tool of Figure 14 substantially defines the outer bounds of the lid, and the tool has been sectioned into quarters. Provision is made to bolt (31) each quarter to its successive neighbour. Provision is made on the core tool for a counter-pin (32) in the shape of the sipper aperture (16) with sufficient length to pierce the corresponding sipper aperture (29) in the cavity. Likewise provision is made in the core tool for a counter-pin (33) in the shape of the breather aperture (17) with sufficient length to pierce the corresponding aperture (30) in the cavity. Each of the counter pins (32 and 33) are housed in a bracket (34), each of which is attached across two quarters respectively. Each bracket (34) retains a spring (35) concentric on their respective counter-pins (32 and 33). Each counter pin is free to travel within the confines of their respective slots (29 and 30), in a direction perpendicular to the bottom surface in the cavity assembly. Each of the counter pins (32 and 33) may be locked in a withdrawn position using a fork like device (36) that slides into a rebate in each pin and rests on the bottom face of each bracket respectively. The counter pressure of the compressed springs (35) on the opposite face of each of the brackets (34) provides enough tension to hold the respective forks (36) in place.

Provision is made in each quarter of the cavity tool for a guide pin guide (37), to receive its respective guide pin on the core assembly tool. Provision is made in the bottom of the core assembly for a plurality of galleries to take heating cartridges (23) and temperature probes (24).

Again, while the faces of each quarter of the core assembly are tightly clamped together, galleries (25) are rebated into the face of each quarter to preferentially duct steam through the part lines. In the case of the cavity assembly, steam is ducted directly to the outside of the tool. No additional galleries or drillings are employed. Like the configuration of the third generation tool, this fourth generation tool allows the cavity tool to be mounted on a single axis gimbal wherein having withdrawn the core, the cavity tool can then be tilted to allow the finished lid to conveniently fall out of the cavity tool assembly.

With particular reference to figure 16, we turn now to the operation of the lid tool assembly.

In the closed position the flanges (38) of each of the core assembly quarters are closed onto the landings (39) of each of their respective cavity quarters having been aligned by their respective core pins (21) and cavity pin guides (37). In this position counter-pins (32 and 33) are in contact with their respective core pins (19 and 20), springs (35) are fully compressed and forks (36) are engaged with their respective counter pins (32 and 33). On disengaging the forks (35) and withdrawing the core assembly, springs (25) on the counterpins (32 and 33) push the counter-pins (32 and 33) through their respective apertures (29 and 30) in the cavity. The tips of the counter-pins (32 and 33) sit proud of their respective apertures (29 and 30) and project into the cavity.

The core and cavity are heated. In this fourth embodiment heating cartridges inserted into the galleries (23) in both the core and cavity assemblies heat their respective assemblies to the set temperatures for each assembly. Temperature is monitored using thermocouples inserted into galleries (24) and maintained using suitable controllers commonly used in industry that will be familiar to one skilled in the art.

The cavity may then be loaded with biodegradable composition mixture and the core closed, whereupon the core pins (19 and 20) re-engage with their respective counter-pins (32 and 33) prior to the core flanges (38) making contact with their respective cavity landings (39). As the core is further closed such that the core flanges (38) make contact with their respective cavity landings (38), the core pins (19 and 20) push their respective counter-pins (32 and 33) back to their starting point thereby sealing their respective cavity apertures (29 and 30). At the same time, the mixture is compressed and heated. Steam is generated in the mixture causing gelatinisation of starch (where present) and/or other chemical reactions where appropriate, at which point the mixture begins to flow throughout the cavity space to substantially fill it. Built up steam may still need to be released by periodically withdrawing the core a small distance, sufficient to allow steam to migrate from within the mixture to the part lines whereupon it is vented to the outside of both core and cavity assemblies. Once sufficient water has been baked out of the mixture the counter pins (32 and 33) may be locked off with their forks (36). The core can then be fully withdrawn and the finished lid extracted. In the case of this fourth embodiment, the cavity is simply tilted on its gimble and the finished lid falls out. The cavity is realigned with the core, the forks (36) are removed from the counter-pins (32 and 33) whereupon the counter-pins (32 and 33) are projected back into the cavity. A further quantity ("shot") of the biodegradable composition mixture may be added and the cycle repeated. Cycle time is determined by combinations of mixture shot size, water content, core and cavity temperatures, the pressure and speed available for closing the arrangement, together with the time to dose the mixture and recover the finished lid. Cycle time may be up to 3 minutes or as little as 1.5 minutes, preferably as little as 30 seconds.

Structural features

It will be appreciated that the general structure or configuration of a container such as a cup is widely known. In general terms, a cup includes a sealed bottom section with wall section around the bottom section and an open end opposite the bottom section.

The cup of the present invention may include a wall section that is thicker than an adjacent wall section of the cup. The wall section may include an area of air or steam cells within the matrix of the wall section to provide extra thickness. It has been surprisingly found by the inventors that by creating air or steam cells in an expanded wall section, it has the advantage of increasing or maintaining strength without requiring more materials, while at the same time provides a thermal buffer to both reduce heat loss from the beverage and to make the cup more comfortable to handle with hot contents.

Additionally, the expanded wall section also retards water ingress into the wall matrix which slows down softening of the cup, particularly with hot liquids. This gives the consumer a much greater degree of security and confidence when using the product. Preferably, the expanded wall section is located around a central portion of the cup when the user would hold the cup.

In one embodiment, the cup may include a lip portion adapted to receive a lid. The lip portion may be formed to include a dense section on an upper part of the cup, relative to a body portion of the cup, and is configured to receive the lid.

In a similar manner, a lid, for example, for a coffee cup, may also include a top section with wall section around the top section and an open end opposite the top section. In this case the top section may be shaped in three dimensions and contain piercings to allow the outflow of beverage and the inflow of air.

Like the cup, the lid wall section may include an area of air or steam cells within the matrix of the wall section to provide extra thickness and provide thermal protection.

Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is to say, in the sense of "including, but not limited to". The entire disclosures of all applications, patents and publications cited above and below, if any, are herein incorporated by reference.

Reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that that prior art forms part of the common general knowledge in the field of endeavour in any country in the world.

The invention may also be said broadly to consist in the parts, elements, characteristics and features referred to or indicated in the specification of the application, individually or collectively, in any or all combinations of two or more of said parts, elements, characteristics or features.

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 herein.

Where in the foregoing description reference has been made to integers or components having known equivalents thereof, those integers are herein incorporated as if individually set forth.

It should be noted that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the invention and without diminishing its attendant advantages. It is therefore intended that such changes and modifications be included within the present invention.