AU3522199A

AU3522199A - Biodegradable packaging material, method for producing same and its use

Info

Publication number: AU3522199A
Application number: AU35221/99A
Authority: AU
Inventors: Andreas Gerhard Baar
Original assignee: AIG ALLG IMMOBILIENVERWALTUNGS
Current assignee: APACK AG fur biologische Verpackungen
Priority date: 1998-03-31
Filing date: 1999-03-31
Publication date: 1999-10-18
Also published as: PL343178A1; EP1070099A1; JP2002509969A; DE19814373A1; KR20010074465A; NO20004891L; CA2324575A1; WO1999050346A1; DE19814373C2; DE19980541D2; NO20004891D0

Description

Biodegradable material for packaging This invention relates to biodegradable material for packaging, a process for producing such a material and the use thereof for the packaging of articles, in particular foods. 5 Nowadays one of the greatest problems with regard to the environment is the avoidance, decrease and disposal of waste material. This manifests itself particularly clearly in the case of moulded articles, such as beakers, plates, 10 cups, bowls, cartons and other containers which are used, for example, for packaging foods and in fast-food restaurants. Thus, for example, foods, in particular those intended for immediate consumption, are often sold in voluminous packaging. Although such moulded articles are 15 relatively light, on being disposed of after use they add to the quantity and volume of durable solid waste material. Because of this, owing to their considerable volume these moulded articles take up space in refuse skips and waste disposal sites. They are also easily blown away by the 20 wind. If such moulded articles are thrown away in the open after the food contained therein has been consumed, over the years they often disfigure the landscape. Many of the materials used to date for the production of 25 the above-mentioned moulded articles are not made from renewable raw materials either, which also produces considerable environmental pollution. From the state of affairs described above, it is clear that 30 there is a great need for a material which can be used for moulded articles, in particular packaging, which is produced predominantly from renewable raw materials and is very rapidly biodegradable. 35 Accordingly, the object of the present invention is to provide a material which is produced predominantly from renewable raw materials and is very rapidly biodegradable.

2 According to the invention, this is achieved by a biodegradable packaging material which is distinguished by having the following components: 5 (a) 45 to 72 wt.% starch, (b) 18 to 45 wt.% cellulose-containing fibres, (c) 0.2 to 10 wt.% fat-containing release agent, (d) 0.05 to 3.0 wt.% emulsifier and (e) 2 to 15 wt.% water, 10 the quantities given in wt.% each being based on the biodegradable material. The material according to the invention thus contains starch as the main component and cellulose-containing 15 fibres, as well as a fat-containing release agent, an emulsifier and water as minor constituents. The packaging material according to the invention may also contain further additives, for example, fillers, such as chalk, kaolin, talc, gypsum, alumina, titanium dioxide or 20 aluminium oxide, fluxing agents, such as magnesium carbonate, magnesium hydroxide carbonate, sodium hydroxide solution and ammonium hydroxide, as well as coloured pigments and food colorants. But the material according to the invention may also consist only of the stated 25 components (a) to (e), that is, there may be no additional components in the material according to the invention apart from those which are present as the usual accompanying substances in the components (a) to (e), for example, contaminants of starch. 30 In the material according to the invention, the starch and the cellulose-containing fibres form a starch-fibre composite which contains the fat-containing release agent, the emulsifier and the water, this starch-fibre composite 35 being formed by gelatinisation of the starch. This means that at least a part of the starch in the material according to the invention can be present in the form of 3 gelatinised starch, and it has been found advantageous that the greater part to the whole of the starch in the material according to the invention, and consequently in the starch fibre composite, be present in the form of gelatinised 5 starch. The term "gelatinised starch" indicates that this is produced from native starch or from chemically and/or physically modified starch by first of all heating the starch in the presence of water and then optionally cooling it. The fat-containing release agent, the emulsifier and 10 the water can be evenly distributed in the starch-fibre composite. The material according to the invention can be produced from a dough containing the specified components (a) to (d) 15 in the proportions required in the material according to the invention, but with the water content being more than 15 wt.%. This dough is packed, for example, into a closed baking mould and thus made into the required shape and subsequently baked. As a result of the baking, part of the 20 water escapes as steam with a great increase in pressure, whereby a material according to the invention is obtained. The steam escapes from the baking mould through openings specially designed for the purpose. The material according to the invention thus produced is removed from the baking 25 mould after the baking process. The starch present in the material according to the invention may originate from natural starch, chemically and/or physically modified starch and mixtures of these. 30 Examples of the natural starch present in the material according to the invention are potato starch, maize starch, rice starch and wheat starch as well as other starches obtained from vegetable materials. Potato starch is preferred, as firstly it is obtainable commercially in 35 large quantities at an economical price and secondly it produces materials according to the invention which have particularly good material properties. In addition, potato 4 starch has a large swelling volume, as a result of which pastes which promote viscosity are obtained, as well as good adhesive properties. 5 The starch is present in the material according to the invention in a quantity of 45 to 72 wt.%, preferably 58 to 66 wt.% and particularly preferably 64 to 66 wt.%, in each case based on the material according to the invention. These quantities of starch in the material according to the 10 invention produce a starch-fibre composite which is mechanically particularly stable as well as a very rapid biodegradability. The material according to the invention contains cellulose 15 containing fibres which, together with the starch which is also present, form the starch-fibre composite described in more detail above, which constitutes the basic structure of the material according to the invention. The term "cellulose-containing fibres" indicates fibres of any type 20 which contain cellulose or consist of cellulose. In a preferred embodiment, the cellulose-containing fibres are pulp fibres, i.e. fibres which can be obtained from pulp. Pulp is a term for the finely fibrous composition, consisting predominantly of cellulose, obtained on the 25 decomposition of wood or other fibrous plants. The term "fibres" used in the present Application indicates fine, thin structures of limited length, with the length being greater than the width. They may be in the form of 30 single fibres or bundles of fibres. Such fibres can be produced in the manner known to the person skilled in the art, and here it has proved to be particularly advantageous if in the production of the fibres the cellulose-containing material is crushed, for example, by means of a hammer 35 mill.

5 In a preferred embodiment of the material according to the invention, the length of the cellulose-containing fibres is in the range of 0.1 to 3.0 mm; the width of the cellulose containing fibres is preferably in the range of 0.01 to 5 0.06 mm. The quantity of cellulose-containing fibres in the material according to the invention is 18 to 45 wt.%, preferably 20 to 30 wt.%, particularly preferably 21 to 24 wt.% and most 10 preferably approximately 24 wt.%, in each case based on the material according to the invention. These quantities of cellulose-containing fibre in the material according to the invention, in a particularly advantageous way, enable the material according to the invention to have a good 15 mechanical stability and an excellent biodegradability. The ratio of starch to fibre in the material according to the invention can be so adjusted that it is 1:1 to 4:1, preferably 3:1 to 2.5:1, for example, approximately 2.7:1. 20 As already explained above, the material according to the invention contains a fat-containing release agent, which is present in a quantity of 0.2 to 10 wt.%, based on the material. The quantity of fat-containing release agent is 25 preferably 0.2 to 2.5 wt.% and particularly preferably 0.6 to 1.3 wt.%, in each case based on the material according to the invention. The term "fat-containing release agent" covers compositions 30 of any type which contain a fat or several different fats and facilitate the release of the material according to the invention from the baking mould after the baking process. Fats are triglycerides, i.e. esters of glycerol, wherein the three hydroxyl groups are esterified by fatty acids. 35 Here the fatty acids in a fat molecule can be identical or different. The fat may be a synthetic or naturally occurring fat, such as a vegetable fat or animal fat. The 6 fat may moreover be partially or completely hardened; completely hardened fats have an excellent stability in storage and do not become rancid. In addition, it is an advantage if the fat-containing release agent has a good 5 stability in storage and a high separation efficiency, and is physiologically safe. It is also useful if the melting point of the fat is above room temperature (approximately 18 0 C), for example, 40 0 C or higher, as a better water repellency of the material according to the invention is 10 thereby achieved. In a preferred embodiment of the fat-containing agent used in the material according to the invention, this agent contains mainly fat. The quantity of fat in the fat 15 containing agent is advantageously at least 90 wt.%, preferably at least 94.5 wt.% and particularly preferably at least 98 wt.%, in each case based on the fat-containing agent. The fat-containing agent may also consist entirely of fat. 20 Besides the fat or fats, the fat-containing release agent may contain small quantities of other constituents such as, for example, oil or wax, neither of which should be fats, or lecithin. 25 The fat-containing agent preferably has the following composition, the data in wt.% being based on the fat containing agent: approximately 64.5 wt.% vegetable fat, approximately 30.0 wt.% animal fat and approximately 30 5.5 wt.% of a mixture of lecithin and a wax, preferably beeswax. This fat-containing agent is distinguished by having an excellent stability in storage, a good separation efficiency and by being physiologically safe. It is accordingly most suitable for an agent according to the 35 invention.

7 Surprisingly, it has now been found that these fat containing release agents, in particular in the quantities used, have no adverse effect on the structural properties of the material according to the invention. The excellent 5 mechanical stability of the packaging material is thus not adversely affected either. Furthermore, the odorous properties of the material are not adversely affected either, despite the high quantities of fat which are introduced into the material according to the invention via 10 the fat-containing release agent; that is, the packaging material does not smell unpleasant, even on prolonged storage. Furthermore, it is not necessary to grease the baking mould used for the production of the material according to the invention and the material can still be 15 easily removed from the baking mould. It is thereby possible to dispense with the greasing of the baking mould with a liquid release agent, which is otherwise necessary in the production of biodegradable materials for packaging, and thus firstly the production is made more economic and 20 secondly there is no ensuing encrustation of the baking mould by the liquid release agent. Moreover, it has been found that the material according to the invention is also rendered water-repellent by the above fat-containing release agent. 25 As already explained above, the material according to the invention contains an emulsifier. Here the term "emulsifier" covers compounds of any type which are amphiphilic, i.e. which contain a lipophilic and a 30 hydrophilic group in the molecule, the emulsifier not being a fat. The emulsifier advantageously has a melting point higher than room temperature, for example, approximately 40 0 C or higher. The emulsifier brings about a homogeneous distribution of the fat-containing release agent which is 35 also present in the material according to the invention. It has also been found advantageous, especially when the material according to the invention is used as packaging 8 for food, that the emulsifier be permitted under the food laws. The emulsifier is preferably a mono- or diglyceride of edible fatty acids, which is esterified with a carboxylic acid, such as citric acid, mono- and 5 diacetyltartaric acid, lactic acid or acetic acid and tartaric acid. These emulsifiers are classified under EEC Number 472. The term "edible fatty acids" is a common term in the field of fats, so that the person skilled in the relevant art knows which fatty acids can be used. The 10 emulsifier can also be a fatty alcohol ether sulfate, a fatty alcohol sulfate, in each case preferably with a higher fatty alcohol (from 12 C atoms), an alkali metal salt of a higher fatty acid (fatty acid with 12 or more carbon atoms), for example, sodium stearate. The emulsifier 15 may also be a mixture of two or more of the above emulsifiers. The quantity of the emulsifier in the material according to the invention is 0.2 to 3.0 wt.%, preferably 0.05 to 20 0.8 wt.% and particularly preferably 0.2 to 0.4 wt.%, in each case based on the material according to the invention. In this connection, it was surprising that with such small quantities, even large quantities of fat-containing agent can be introduced homogeneously into the material according 25 to the invention. Surprisingly, the water-repellency of the material according to the invention is improved by the emulsifier. In addition, the separation efficiency can also be improved 30 with the emulsifier, that is, after the dough which constitutes the material according to the invention has been baked, the material according to the invention can be removed from the baking mould even more easily. 35 In addition, water is present in the material according to the invention in a quantity of 2 to 15 wt.%, preferably 6 9 to 12 wt.%, in each case based on the material according to the invention. Preferred materials according to the invention are shown in 5 Table 1 below. Table 1: Composition of materials according to the invention (in wt.%) Type of Z1 Z2 Z3 Z4 Z5 Z6 Z7 Z8 Z9 Z10 Z11 raw material Starch 65.5 65.4 65.1 64.8 64.4 65.1 64.8 64.5 64.2 62.9 59.5 Fibre 24 24 24 24 24 23 23 23 23 22 21 Fat 0.2 0.3 0.6 0.9 1.3 1.6 1.9 2.2 2.5 4.8 9.2 Emulsifier 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Water 10 10 10 10 10 10 10 10 10 10 10 Type of Z12 Z13 Z14 Z15 Z16 Z17 Z18 Z19 Z20 Z21 Z22 raw material Starch 65.75 65.5 65.2 64.8 64.3 64.9 64.5 64.1 63.7 61.6 57.1 Fibre 24 24 24 24 24 23 23 23 23 22 21 Fat 0.2 0.3 0.6 0.9 1.3 1.6 1.9 2.2 2.5 4.8 8.9 Emulsifier 0.05 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 1.6 3.0 Water 10 10 10 10 10 10 10 10 Starch: potato starch Fibre: pulp fibre Fat: mixture of 64.5 wt.% vegetable fat, 30 wt.% animal fat and 5.5 wt.% lecithin and beeswax Emulsifier: monoglyceride citrate 10 The material according to the invention excels in having a multitude of advantages. Firstly, it has a high mechanical stability, which is still very high even where the thicknesses (wall thicknesses) of the material are small, 5 i.e. approximately 2 mm. This excellent mechanical stability is achieved in particular through the high content of cellulose-containing fibres, which may be to up to 45 wt.%. At the same time the flexibility of the material according to the invention is very high, which is 10 particularly surprising, as cooled starch is very brittle. In addition, the material according to the invention is resistant to cold water for up to 1 hour. Furthermore, articles produced from the material according to the invention, for example, a container and an accompanying 15 lid, can be bonded together by moistening with water, with a very good adhesion of the two articles to one another being achieved. The material according to the invention is also virtually completely biodegradable within 28 days, in accordance with DIN 54900. Moreover, the material according 20 to the invention is stable in storage for a long period, i.e. during storage there is no change in the material according to the invention. The material also consists predominantly of biologically occurring raw materials and can therefore be referred to as "biological" material. 25 Finally, the material according to the invention need not be adjusted to a specific water content by means of a special conditioning step. The material according to the invention can consequently be 30 used extremely well as material for moulded articles (i.e. articles which have a definite shape) of any type, for example, as disposable tableware, as fast-food packaging (containers for hamburgers and chips), as packaging for foods, for example, dry, moist, paste-like and fried food. 35 After a biodegradable barrier layer has been applied to the material according to the invention, this can then be used 11 as a receptacle for liquid foods, such as hot beverages and soups. The moulded articles can assume any shape, for example, the 5 shape of a bowl, a plate, a beaker, a dish. Further examples of moulded articles which can be produced with the material according to the invention are shown in Figures 1 to 4. 10 In addition, the moulded articles may have the shape of an urn, of the type used for cremations, or the shape of a rocket, as used for fireworks. The present invention also provides a process for producing 15 a material for packaging, in particular of the type described above, wherein first of all a baking composition is prepared by mixing 7 to 22 wt.% cellulose fibres, 18 to 36 wt.% starch, 0.1 to 4.6 wt.% fat-containing release agent, 0.1 to 1.5 wt.% emulsifier and 50 to 60 wt.% water, 20 in each case based on the baking composition, and then baking this composition, with the formation of a moulded article. The term "baking composition" indicates compositions of any 25 type which can be baked, i.e. expanded by steam. The baking composition which is used in the process according to the invention can be described as soft, semisolid dough. After the baking process, a product (material) of the 30 following composition can be obtained: (a) 45 to 72 wt.% starch, (b) 18 to 45 wt.% cellulose-containing fibres, (c) 0.2 to 10 wt.% fat-containing release agent, 35 (d) 0.05 to 3.0 wt.% emulsifier and (e) 2 to 15 wt.% water.

12 It can, therefore, be the packaging material according to the invention described in more detail above. Consequently, it is advantageous if the starch, the cellulose-containing fibres, the fat-containing release agent and the emulsifier 5 used in the process according to the invention are the components used above in connection with the material according to the invention. A preferred quantity of starch used in the process 10 according to the invention is 30 to 32 wt.%, based on the baking composition. In a preferred embodiment of the process according to the invention, the quantity of cellulose-containing fibre is 10 15 to 12 wt.%, based on the baking composition. The fat-containing release agent in the baking composition is preferably 0.1 to 1.2 wt.%, with 0.3 to 0.6 wt.% being particularly preferred. 20 The preferred quantity of emulsifier used in the baking composition in the process according to the invention is 0.03 to 0.4 wt.%, particularly preferably 0.1 to 0.2 wt.%. 25 The water may be present in the baking composition in the process according to the invention in a quantity preferably of 54 to 58 wt.%. In the process according to the invention, the cellulose 30 containing fibres are preferably used in the form of a non woven fabric. For this, the cellulose-containing fibres are first of all processed to form a non-woven fabric in the conventional manner. A non-woven fabric composed of cellulose-containing fibres can be produced, for example, 35 by crushing webs of pulp with a hammer mill (unravelling them), individual fibres thus being obtained. These individual pulp fibres are then processed to form a 13 non-woven fabric, as is conventional, for example, in the hygiene industry for producing cotton wool for sanitary towels. In the additional steps of the process according to the invention, the non-woven fabric can be spread out flat, 5 for example, on a conveyor belt. The remaining components (a) and (c) to (e) are then applied to the non-woven fabric on this non-woven fabric spread out on the conveyor belt. Here the conveyor belt can serve to transport the non-woven fabric to the positions at which the addition of the 10 remaining components takes place. In a preferred embodiment of the process according to the invention, the starch consists partly of native starch and partly of boiled starch (starch which has been heated in 15 water (boiled)). The favourable proportion of native starch to boiled starch is in the range of 1.0:1 to 4.0:1, preferably 2.5:1 to 3.5:1, particularly preferably approximately 3:1. The boiled starch can contain the entire water content of the dough as well as the emulsifier, the 20 fat-containing agent and optionally other additives. The native starch and the chemically and/or physically modified boiled starch can be added separately to the cellulose containing fibres. 25 For the separate addition of the native starch and the boiled starch, it has been found particularly advantageous to proceed in the following manner:- A mixture is prepared in a boiler by mixing together the water, the fat containing agent, the emulsifier, optionally other 30 additives and a portion of the starch in the form of native starch and heating for 10 minutes to 1 hour, preferably 20 minutes to 40 minutes, at a temperature of 600C to 800C, preferably 64*C to 680C. As a result of heating the starch containing mixture in the boiler, the originally added 35 native starch is converted into gelatinised starch (boiled starch). Ultimately, this means that the cellulose containing fibres are mixed both with the gelatinised 14 starch in the form of the mixture described above and with the native starch, namely, the remaining portion of all the starch. 5 It is possible to add first of all the boiled starch and then the native starch to the cellulose-containing fibres. However, the native starch can first of all be added, and then the boiled starch. If the cellulose-containing fibres are in the form of a non-woven fabric, for example, on a 10 conveyor belt, then the mixture containing the boiled starch described above can first of all be applied to the non-woven fabric, whereby a two-layered structure is obtained, to which the native starch is then applied, for example, by trickling or scattering. Surprisingly, it has 15 now been found that this procedure ensures that a precise composition in small volume elements, which can then be easily processed into a baking composition, is achieved. After having been combined, the above-mentioned components 20 are mixed. Here the components can be mixed in a conventional manner, for example, by kneading with a kneader, such as a continuous kneader. In the course of kneading there may be a resulting reduction in volume of approximately 7:1, because the fibres have a very low 25 density. The kneading process is considerably facilitated through the addition of the precise composition in small volume elements. The baking composition obtained is then baked. For this, 30 the baking composition is placed (metered) into a baking mould and heated in the closed baking mould for 0.5 minutes to 15 minutes, preferably 1 minute to 3 minutes and particularly preferably 1.5 minutes, at a temperature of 1000C to 300 0 C, preferably 150 0 C to 220 0 C and particularly 35 preferably 190 0 C to 200 0 C. The baking mould is fashioned according to the shape of the required end product, for example, in the shape of a bowl. The baking mould can be 15 formed by at least two baking plates, i.e. an upper and a lower baking plate, which are held in baking tongs, the internal surface of the baking plates being kept apart while the baking mould is maintained in the closed position 5 by bolts, with the formation of a mould cavity, and the mould cavity is filled with the baking composition. The baking mould has specially shaped openings for release of the steam. A large number of baking tongs can also be used for the simultaneous production of a large number of 10 moulded articles. The baking composition can be metered into the baking mould by compressed air, spiral conveyors, pumps or by application of a vacuum, the use of compressed air being preferred. The metering can be carried out at a temperature of up to 804C. 15 Such devices for baking are based on the known per se technology of waffle baking. While the baking composition is in the process of being 20 baked, the water contained in this composition is removed. Here it is advantageous to design the baking process in such a way that the residual water content in the material obtained after baking is less than 5 wt.%. Through the removal of the water, the composition is expanded and the 25 starch contained in the composition is gelatinised, whereby the previously described material according to the invention having the starch-fibre composite structure can be obtained. In storage or in normal use, the material according to the invention can take up water from the 30 environment, so that the water content is ultimately 5 to 15 wt.%, preferably 6 to 12 wt.%, based on the baking composition. The process according to the invention has a number of 35 advantages. Owing to the special composition of the baking composition, the flowability of the baking composition used in the process according to the invention is distinctly 16 improved, so that the per se highly viscous baking composition can be accurately metered by metering pumps. It is thereby possible to carry out the process according to the invention continuously. Furthermore, it is not 5 necessary to grease the baking mould. All moulded articles produced by the process according to the invention were able to be produced quickly, economically and with excellent material properties as regards stability of form, fracture strength and elasticity, density of structure and 10 surface condition. Owing to the special composition, the material according to the invention, with a water content of less than 5 wt.%, immediately after baking is already so outstandingly stable that it can be further processed or used straightaway. 15 Short description of the Figures: Figures 1 to 4 show examples of moulded articles which can be produced with the material according to the invention. 20 Figure 1 shows an article of moulded packaging 1 which has a base and cover section 2,3, connected by a hinge 4, and is suitable for use, for example, as a closable receptacle for food, even in the hot state. Owing to the high 25 elasticity, the hinge 4 produced from the material according to the invention can be repeatedly opened and closed. This is all the more amazing, as materials based on starch are usually extremely brittle and fracture easily. 30 Figure 2 shows a moulded article 1 in the form of an open rectangular container, which can also be combined with a corresponding counter moulded article to form a completely closed package. The tray-shaped moulded article 1 has a multiplicity of semicylindrical indentations 5, each of 35 these being subdivided into a longer segment 6 and a shorter segment 7; this arrangement is repeated symmetrically on the other side of the moulding, separated 17 by a central crosspiece 8. Lateral "feet" 9 increase the stability of the shape and improve the support and stacking properties of the moulded packaging. Such a packaging container can be used, for example, as a receptacle for 5 ballpoint pens, lipsticks, cosmetic articles, pencils, writing implements, or in pharmacy, for example, as a receptacle for packaging tubes. Figures 3 and 4 show relatively deep moulded articles 1, of 10 the type which can be used, for example, as flowerpots, seedboxes or for other packaging or covering purposes. The following Examples illustrate the invention. 15 Examples 1 to 22: Production of materials according to the invention Baking compositions (doughs), the composition of which is given in Table 2, were prepared as follows: 20 The given quantities of water, emulsifier, fat-containing agent and the proportion of native potato starch indicated in Table 2 as being boiled starch were placed in a boiler and heated at approximately 65 0 C for approximately 30 25 minutes, with stirring. Boiled starch which also contained the emulsifier and the fat-containing agent was thus obtained. A pulp non-woven fabric was produced in conventional manner 30 from pulp fibres of 0.1 mm to 3.0 mm in length and 0.01 to 0.06 mm in width. The pulp non-woven fabric was then spread out flat. To this pulp non-woven fabric was then applied first the boiled 35 starch described above, so that a layer of boiled starch containing an emulsifier and fat-containing agent was formed on the pulp non-woven fabric. The quantity of native 18 starch given in Table 2 was then scattered onto the layer of boiled starch. The composition thus obtained was subsequently introduced into a kneader and therein thoroughly kneaded in order to blend the components, 5 whereby a baking composition (dough) was obtained. The dough was then placed in a baking mould and baked at approximately 1954C for approximately 90 seconds. 10 Materials according to the invention, which were produced predominantly from renewable raw materials and were rapidly biodegradable, were thus obtained. Moreover, these materials had a high mechanical stability at a wall thickness of approximately 2 mm, accompanied by good 15 flexibility, and were resistant to cold water for up to 1 hour.

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Claims

1. Biodegradable packaging material, comprising: 5 (a) 45 to 72 wt.% starch, (b) 18 to 45 wt.% cellulose-containing fibres, (c) 0.2 to 10 wt.% fat-containing release agent, (d) 0.05 to 3.0 wt.% emulsifier and (e) 2 to 15 wt.% water. 10

2. Material according to claim 1, characterised in that the starch is potato starch, maize starch, another vegetable starch or a mixture of various starches. 15

3. Material according to claim 1 or 2, characterised in that the starch is present in a quantity of 58 to 66 wt.%, based on the material.

4. Material according to one of claims 1 to 3, 20 characterised in that the cellulose-containing fibres are pulp fibres.

5. Material according to one of claims 1 to 4, characterised in that the cellulose-containing fibres 25 have a length in the range of 0.1 mm to 3.0 mm.

6. Material according to one of claims 1 to 5, characterised in that the cellulose-containing fibres have a width in the range of 0.01 mm to 0.06 mm. 30

7. Material according to one of claims 1 to 6, characterised in that the cellulose-containing fibres are present in a quantity of 20 to 30 wt.%, based on the material. 35 21

8. Material according to one of claims 1 to 7, characterised in that the fat-containing release agent is present in a quantity of 0.2 to 2.5 wt.%, based on the material. 5

9. Material according to one of claims 1 to 8, characterised in that the fat-containing agent contains mainly fat.

10 10. Material according to one of claims 1 to 9, characterised in that the fat-containing release agent also contains at least one component, selected from oil, wax and lecithin. 15

11. Material according to one of claims 1 to 10, characterised in that the emulsifier is a mono- or diglyceride of edible fatty acids, which is esterified with a carboxylic acid, or is a fatty alcohol ether sulfate, a fatty alcohol sulfate or an alkali metal 20 salt of a higher fatty acid.

12. Material according to claim 11, characterised in that the carboxylic acid is citric acid, mono- and diacetyltartaric acid, tartaric acid, lactic acid or 25 acetic acid and tartaric acid.

13. Material according to one of claims 1 to 12, characterised in that the emulsifier is present in a quantity of 0.05 to 0.8 wt.%, based on the material. 30

14. Material according to one of claims 1 to 13, characterised in that the water is present in a quantity of 6 to 12 wt.%, based on the material. 22

15. Process for producing a biodegradable material for packaging, wherein first of all a baking composition is prepared by mixing 7 to 22 wt.% cellulose fibres, 18 to 36 wt.% starch, 0.1 to 4.6 wt.% fat-containing 5 release agent and 0.03 to 1.5 wt.% emulsifier and 50 to 60 wt.% water, in each case based on the baking composition, and then baking this composition, with the formation of a moulded article. 10

16. Process according to claim 15, characterised in that the cellulose-containing fibres are used in the form of a non-woven fabric.

17. Process according to either of claims 15 or 16, 15 characterised in that the starch consists of native starch and boiled starch.

18. Process according to claim 17, characterised in that the ratio of native starch to boiled starch is in the 20 range of 1:1 to 4:1.

19. Process according to one of claims 15 to 18, characterised in that the native starch and the boiled starch are added separately to the cellulose 25 containing fibres.

20. Process according to claim 19, characterised in that the boiled starch contains the fat-containing release agent and/or the emulsifier. 30

21. Process according to claim 19 or 20, characterised in that first of all the boiled starch and then the native starch are added to the cellulose-containing fibre. 35 23

22. Process according to one of claims 15 to 21, characterised in that the baking is carried out at a temperature of 100 0 C to 3000C. 5

23. Process according to one of claims 15 to 22, characterised in that baking is carried out for 0.5 minutes to 15 minutes.

24. Process according to one of claims 15 to 23, 10 characterised in that baking takes place in a closed mould with increase in pressure as a result of the evaporation of water.

25. Process according to one of claims 15 to 24, 15 characterised in that the mixing is effected by kneading.

26. Use of the material according to one of claims 1 to 14 as packaging material.