The present invention relates to kitchenware, and in particular to receptacles which are used for absorbing and disposing of cooking fats, oils or grease.

Fats, oils or grease are present at the end of many cooking or other food preparation processes. They may comprise fats or oils which have been used to cook or otherwise prepare the food, and/or fats or oils which have originated from the foodstuffs.

In some contexts the fats or oils are re-used in further cooking processes, whereas in other contexts the fat or oils are disposed of: the present invention is concerned with the latter. Waste cooking oils can be disposed of in several ways. Disposal into drainage systems is generally discouraged because wastewater systems do not process oils effectively, the disposed oils can cause blockages (particularly as they often solidify on cooling), and oils disposed of in this way may cause environmental problems. Nevertheless, many people do dispose of waste oil in this way for convenience, particularly in a domestic setting. However, regulations regarding the use of drainage systems, and regarding environmental matters, are becoming stricter, and public awareness of the problems is increasing, as is willingness to consider more responsible disposal. Waste oil or fat can be poured or scrapped into a waste container. This commonly ends up in landfill or alternatively can be further processed (e.g. composted, digested or used in fuel processes).

Many people dislike dealing with the waste oil or fat, and find it inconvenient and/or messy to dispose of it. A small improvement in convenience and a way of making the disposal process slightly more appealing could result in a significant change in behaviour.

Various receptacles are known which have been specifically designed to contain waste cooking oil or fat, and which comprise disposable materials to absorb the waste oil or fat.

GB 2 368 261 discloses a receptacle for spent cooking oil comprising an

impermeable casing, an aperture within said casing enabling access thereto, and an oil absorbent matrix within the casing. The matrix may be a sponge or pad, and may comprise beads or fibres, and occupies all of the interior of the casing. The product is designed to be disposable in its entirety.

US 3,487,439 discloses various cans containing grease-absorbent material. A first can contains a loosely packed body of grease-absorbing material (e.g. paper pulp) above which there is a perforated top wall which serves as a screen to prevent food particles from entering the container: the entire receptacle is designed to be thrown away when full. A second can contains a conventional toilet-tissue roll with its hollow central core disposed vertically. A third can contains a pre-formed body of grease-absorbent material such as paper pulp with a concave upper surface and a hollow central core extending vertically from the upper surface towards the bottom of the container. This concentrates the liquid grease into the hollow central vertical core as it is poured into the container. WO 2007/009249 discloses a waste absorbent device comprising a biodegradable container and a combination of an oil-absorbent material and water-absorbent material enclosed within said container, said device including a liquid permeable layer to permit liquid to enter the container and be absorbed by the combination of absorbent material. The device may resemble a low wide-mouthed cup both in shape and size. The multi-component inner core is described as a waste sponge. The receptacles described above suffer from various issues, and, as far as we are aware, none has been successfully commercialised.

From a first aspect the present invention provides a disposable, grease-absorbing tray for waste cooking grease, formed so as to contain channels on its upper surface to distribute grease horizontally across the tray.

The design of the tray allows it to capture oil in an efficient manner. A user will typically want the process of transferring waste oils from a cooking pan or other vessel to the tray of the present invention to be quick and easy, particularly if the oil is hot or odorous. A typical user is not likely to be concerned about ensuring that the tray absorbs a maximum amount of oil. Nevertheless it is important that the tray is used efficiently so that it can function effectively by absorbing further oil after absorbing a first batch of oil, and so that it requires replacing less often. This is important because if the tray requires replacing only infrequently then the convenience will make a user much more likely to adopt this method of dealing with waste cooking grease rather than for example simply pouring it down the sink.

The present invention allows the oil to flow laterally across the tray so as to utilise the full capacity of the tray. The distribution may be generally radial, i.e. roughly from the central part of the tray outwards towards the perimeter of the tray

Furthermore the channels provide effective greater surface area: the oil contacts not just the base of the channels but also the side walls of the channels.

The channels may be interconnected so that they take the form of a network or lattice.

Optionally the channels may be relatively large, for example they may have a minimum horizontal dimension of at least 5mm or at least 10mm. We have found that this is advantageous because smaller channels are less effective in allowing distribution, possibly due to the viscosity and solidification properties of typical waste oils from cooking processes. Whilst, optionally, the channels responsible for facilitating the distribution of the grease may be relatively large, there may nevertheless be surface details at a smaller scale: such surface details can add surface area and/or can enhance aesthetic qualities.

The upper surface of the tray (i.e. the surface onto which the oil is poured) may comprise upstanding members between interconnected channels. The upstanding members may take the form of nodules, slabs, or other raised areas. The upstanding members and channels may resemble dints and grykes respectively.

The arrangement brings advantages because some of the oil is absorbed into the upstanding members and some runs off the upstanding members and is distributed to other parts of the tray.

The upper surface of the upstanding members may be rounded to facilitate the flow of the oil off the upstanding members down their side walls and into the channels.

The tray may be moulded so that, whilst there are upstanding members, raised areas or projections (which from above may resemble nodules, slabs or dints), these are generally not solid but are hollow. This allows the wall thickness to be approximately uniform regardless of whether it is the wall at the base of a channel or the wall at the top or side of an upstanding member. In turn this allows more even distribution of the oil into the material of the tray so as to use the full oil- absorbing capacity of the tray.

The tray may therefore be considered to be a moulded or formed sheet which has been shaped to provide channels. A moulding process may be used to form relatively thin walls, though there may be localised areas of greater thickness, e.g. in "tight" areas (such as areas of greater curvature) where clumping may occur.

Double or multiple dipping may also be carried out to form thicker walls. Therefore, for example, a particular mouldable composition may be used to form a base sheet thickness of up to 3mm generally, or greater if double dipped, with some localized thicker areas (e.g. up to 20mm locally). Optionally the wall thickness of the tray may be between 1mm and 20mm, e.g. between 1mm and 10mm (or 1mm to 4 mm) in most areas, with some sections up to 20mm.

The tray may have a camber, i.e. a convex shape, such that constructional features towards the outside of the tray are lower than the same constructional features at the centre of the tray. For example the base of the channels towards the outside of the tray may be lower than the base of the channels in the middle of the tray. A user will typically pour the waste oil centrally, and the camber will then facilitate the flow of the oil so that it is distributed not just in the centre but also radially towards the outside of the tray. Other constructional features may also be cambered: for example the upstanding members or nodules near the periphery may be lower than those upstanding members or nodules near the centre of the tray.

Whilst the channels and upstanding members occupy most of the area of the tray, there may also be an upstanding peripheral wall to stop the oil flowing beyond the edges of the tray. This wall may be higher than the upstanding members.

Some of the advantages of the present invention lie in the elegance or simplicity of the product. The present invention provides a block of matter which works on its own and does not need to be contained within anything else. In contrast GB 2 368 261, US 3,487,439 and WO 2007/009249 disclose more complicated arrangements where multiple components are required or where loose material is held within other structures. The present invention provides a matrix which has both a formed shape (it is rigid and self-supporting) and also an absorbent capacity. Nevertheless, the tray of the present invention may be used within a container or "bin". This is preferred in some environments in order to improve appearance and/or contain odour. The tray or insert is easily introduced and removed, unlike absorbent components in GB 2 368 261, US 3,487,439 and WO 2007/009249.

The tray may be made from various materials. A number of suitable absorbent materials are known: the key requirement is that they should be able to absorb waste cooking grease. Trays based on cellulosic fibres are particularly effective. The cellulosic fibres may be derived from various pulps including those from paper or wood material, or from other plant sources. One example of a suitable absorbent material is "Absorbent W" available from Absorption Corp., Ferndale, Washington, United States. A further advantage of using trays made from cellulosic material is that the used tray together with its payload of used grease, may be fed into a degradation, composting or fuel generating process.

From a further aspect the present invention provides a receptacle for containing waste cooking grease, comprising a bin, and a tray as described above for locating within the bin.

The optional wall of the tray may have a lip which may rest on the edge of the bin. This can result in a gap between the base of the tray and the base of the bin, which avoids the transfer of residue from the former to the latter. In an alternative arrangement the tray may not rest or hang from the edge of the bin but may rather sit on the base of the bin.

The tray and bin are generally sized so as to fit together, so that the edges of the tray go to the edges of the bin. Advantageously the bin may have a lid so that the waste oil material is not visible and so that the whole unit may have a pleasing appearance and be suitable for positioning on a worktop or other location within a kitchen environment. The product may be used within a domestic or commercial setting.

Whilst the tray is disposable, and will be replaced as many times as necessary, the bin is designed to be re-used and therefore is made from a suitable durable material. Some examples of suitable materials are: polycarbonate, ABS, polypropylene or any other commercially available form of mouldable plastic; or a metal or ceramic material.

Optionally the container may be low and wide-mouthed. The container may optionally have a cross-sectional area of 150 to 1,000 cm ² , e.g. 200 to 500 cm ² , e.g. 200 to 300 cm ² or 300 to 500 cm ² . The container may optionally have a height of 3 to 10 cm, e.g. 4 to 5cm. Some specific examples of suitable dimensions are 25.5 x 15.5 x 4.5 cm and 15.5 x 15.5 x 4.5 cm.

Where the tray is used on its own rather than within a bin it may have an outer coating or layer on its base, to prevent grease soiling a kitchen surface. This coating or layer is grease-impermeable and may for example be of foil or plastic.

The present invention will now be described in further, non-limiting, detail, with reference to the following figures in which:

Figure 1 shows an absorbent tray for absorbing waste cooking grease in accordance with the present invention, in profile cut-away view; and

Figure 2 shows a receptacle comprising said tray inside a suitably designed bin. Referring to Figures 1 and 2, tray 1 is moulded from pulp material and is formed so as to comprise interconnected channels 3 between upstanding nodules 5. At the edge of the tray 1 there is an upstanding peripheral wall 7. As can be seen in Figure 1, a camber is present so that the bases of the channels lie along a generally convex curvature. This means that channels towards the outside of the tray (for example channel 3b) are lower than channels towards the centre of the tray (for example channel 3a). In Figure 2, tray 1 is shown disposed within bin 12. Lid 15 is also provided to cover the receptacle.

Example 1 - Manufacture of trays In one example, a cellulosic pulp is mixed with water to form a composition containing 96 - 97% water by weight. The composition is heated and mixed.

Tooling dips into a vat containing the mixture (multiple products are made at once) and a vacuum is used to draw the pulp onto the tool. The tooling extracts and the mouldings are pressed onto a negative tool and then pushed off onto a conveyor and then go through an oven to dry.

Example 2 - Absorption of waste cooking grease

The absorbent material used was Absorbent W, available from Absorption Corp., Ferndale, Washington, United States of America. This was tested in bulk (loose) form, and in manual and machine formed compression mouldings. The

performance of the material in the various forms was tested with samples of fats derived from mammals, poultry and fish and also vegetable (cooking) oils, with and without moisture present. The fats tested in some cases had (waste) particles from the cooked item mixed into the liquid. The material showed a ready of absorption of fats and oils. Warm or hot fats poured into the material were absorbed, with heat aiding absorption. As the material reached local saturation, pools of fat were formed. These could be encouraged to flow to other areas to continue absorption. As the fats cooled, they solidified and became locked into the material. Addition of more hot material remelted the fat and allowed further absorption. Increasing the surface area to volume ratio resulted in optimal absorption as this allowed for best fluid flow before solidification. In some cases solid matter particles adhered to the surface of the insert as the fat set.

Cooking oils were readily absorbed by the insert, with heat again aiding absorption. Cooking oils tended not to set at room temperature but were retained by the insert, unless over-saturated in which case some slight leakage was observed, which could be caught by the bin.

The material generally absorbed two to three times its weight in fat or oil.