METHOD FOR ITS PRODUCTION

Technical Field

The invention relates to mouldings, specifically to mouldings of biodegradable material, and to a method for producing the mouldings.

State of the Art

The processing of grain generates a large amount of waste, which is bran. The most frequent way of processing them is to feed them to farm animals.

At present, a wide range of biodegradable products are also known.

From patent PL 171 872 is known a material containing 30 to 85 wt% biodegradable synthetic material and 15 to 70 wt% starch or unmodified cellulose as biodegradable additives, as well as small amounts of adjuvants. This material is obtained by melting its polysaccharide base and adding starch or cellulose to the melt. This mixture initially takes the form of a dispersion of starch having a moisture content of not more than 25% or cellulose in a polysaccharide base. Then the mixture is pelletised and the pellets are used to shape the desired products in moulds. This method is relatively complex and involves many stages.

From the patent application CZ PV 2002-1917 there is known a material for the production of biodegradable bran mouldings, in particular tableware and packaging containers, which consists of a 95 to 100 wt% mixture of loose bran, in particular wheat, forming the selected fraction of bran having a grain size of from 0.01 to 2.80 mm, containing from 7 to 45 wt% structurally bound water in the form of moisture and optionally up to 5 wt%, based on the weight of the composition, of impregnating agents and/or fragrance additives and/or flavour delivery additives and/or non-fibrous fillers and/or water retaining agents and/or colouring agents. A process for the production of these biodegradable mouldings is characterised by that the bran, in particular wheat bran, with a grain size of 0.01 to 2.80 mm in an amount of 96 to 100 wt%, based on the weight of the mixture, contains 7 to 45% structurally bound water in the form of moisture, is dry blended with a mixture of impregnating substances and/or fragrance and/or flavour delivery additives and/or fibre fillers and/or water retaining agents and/or colouring agents in an amount of up to 5 wt%, based on the weight of the mixtures. A measured amount of this moulding material thus obtained is placed on part of a multipart mould, preferably a multipart mould. The mould is closed, while exposing the moulding material therein, for several tenths of a second to a temperature in the range of 20 to 450°C and a pressure in the range of 1 to 10 MPa and/or a compressing force of up to 100 t/cm2 at a pressure up to 320 MPa acting on the piston closing the mould. A disadvantage of the above- described material is that the products made therefrom are shape stable for a relatively short time.

From patent PL167213 is further known a process for the production of thin- walled biodegradable fittings. The method is characterised by that it consists of a mixture comprising, based on weight of 30 to 63 wt% water, 27 to 69 wt% starch base, an anti-adhesive agent, thickener, up to 16 wt% cellulose-rich raw materials, up to 10% non-fibrous binders, moisture retention agents, dye, hardener, a preservative substance and an antioxidant, baked in the mould for 25 to 230 seconds at 145 to 230°C and then stabilised until a moisture content of 6 to 22 wt% of the composition is reached. This method can be used to make disposable cups, fast food trays, packaging boxes, food packaging inserts, as well as sheets or strips of a paper or cardboard-like nature. The products obtained in this way have a wall thickness which, on the one hand, is sufficiently thick to achieve the required resistance to breakage and splitting, and, on the other hand, thin enough to allow effective baking between two halves of the conventional moulds used in machines for the automatic baking of wafers. The disadvantage of this production method is its relative complexity and material demands.

From current technology is also known a dry composition for tableware which contains products obtained by grinding cereal grains in an amount of 50 to 95 wt%, based on the weight of the composition, dry substances, products produced from crushing potatoes, soybeans and other plants in an amount of 0 to 90 wt% of the dry matter, based on the weight of the mixture, and animal protein as a binder in an amount of up to 30 wt%, based on dry matter, as well as fragrance or aroma imparting additives, preservatives and colouring agents. The above ingredients are mixed together with water and kneaded until a homogeneous dough is obtained. The dough is then extruded and baked in the usual manner for several minutes. A disadvantage of this material is that during the baking process the water contained in the dough evaporates, leading to the destruction of the homogeneous fibrous structure of the fittings. The finished products thus exhibit numerous same sized large cracks.

From CZ 306063 is further known a process for the production of wheat bran mouldings, according to which a compression mixture is first prepared by mixing 4 to 20 wt% urea, 4 to 20 wt% catalyst, 4 to 20 wt% paraformaldehyde and 40 to 88 wt% bran, and then this mixture is pressed. A major disadvantage of the moulding produced is that it cannot be disposed of as feed for farm animals.

From a further patent EP 2900872 is known a process for the production of biodegradable mouldings, particularly tableware and packaging, using a method of applying water vapour pressure within a multi-part mould. The process comprises mixing loose bran with a grain size of 0.01 to 2.80 mm in an amount of 95 to100 wt% containing more than 14 wt% water structurally bound in the form of moisture with impregnating agents, flavouring agents, fragrance agents, non-fibrous fillers, humectants, colouring agents or combinations thereof, in an amount of up to 5 wt% to achieve a mixture of loose material, followed by heating the mould to 120 °C or higher; the loose material mixture is poured into one of the parts of the multi-part mould, after which the mixture is subjected to a simultaneous temperature and pressure action of from 1 MPa to 10 MPa, followed by depressurising the mould by creating a 0.5 mm gap or less between the edges of the form by water vapour within the mould, with depressurisation being performed at least once; and opening the mould, where the steps of closing the mould, exposing the mixture to simultaneous temperature and pressure, and depressurising the mould are performed by pre-programmed machinery that numerically controls the movement of the multi-part mould depending on the expected parameters of the finished product. The disadvantages of such mouldings are high brittleness and low moisture resistance, which, for example, does not allow for their longer storage.

From the aforementioned state of technology, a number of disadvantages is evident from the current known technology, while the most significant disadvantage appears to be that known products made of biodegradable materials either are not resistant to moisture, even air humidity, or contain substances that limit their ecological disposal while for example, they do not allow for their being fed to farm animals. The object of the invention is a moulding made of a biodegradable material, which is grain bran and a process for its manufacture that is simple and inexpensive, and the mouldings will be shape stable, moisture resistant and long-term storable.

Principle of the Invention

The mentioned disadvantages are largely removed and the objectives of the invention are fulfilled by a moulding, specifically a moulding from biodegradable material, specifically a moulding containing cereal grain bran, according to the invention in that it comprises 70 to 95 wt% of cereal grain bran and 5 to 30 wt% oil plant pomace. The advantage is that the moulding is easily compressible and at the same time resistant to moisture, both in the air and direct.

To advantage, the oil plant pomace is rapeseed cakes. The advantage is that the rapeseed cakes are plentiful and cheap. Alternately, sunflower, flax, poppy, or sesame press cakes or olive pomace can also be used.

It is to further advantage that the cereal grain bran is wheat bran. The advantage is again easy availability and price. Alternately, the bran used may be rye, barley or oat bran.

The moulding to further advantage comprises 1 to 15 wt% structurally bound water in the form of moisture. The advantage is that a certain quantity of residual moisture reduces the fragility and brittleness of the moulding.

The mentioned disadvantages are largely removed and the objectives of the invention are fulfilled by a method for producing a moulding, specifically a moulding from biodegradable material according to the invention characterised by that firstly 70 to 95 wt% of cereal grain bran is mixed with 5 to 30 wt% of oil plant pomace, then the mixture is metered into a press mould in which pressing is subsequently carried out. The advantage is the simplicity of this production method.

It is preferred that the mixture is metered into a press mould preheated to 60 to 250°C, with the preheated mould to advantage being for use with mouldings having a higher input moisture content of the material composition from which they are made.

In certain applications, it is to advantage that the mixture is metered into a press mould which is subsequently heated to 60 up to 250°C. Heating the mould or its parts after filling with the mixture is advantageous, especially for mixtures with lower input moisture.

It is also to advantage that the mixture is metered into a press mould comprising at least two parts, while to greatest advantage the mixture is metered into a press mould comprising at least two separately heatable sections, which are usually the upper and lower mould sections and optionally other movable parts of the mould, for example a moveable core. The advantage is the possibility of making a moulding having different properties in its individual parts. This is possible, for example, by providing one side of the moulding with a different surface homogeneity. The movable core allows drawing the final preform moulding produced at the beginning of the pressing cycle. This allows the mixture to behave at high temperature and high pressure, when it has a likeness to plastic mass, that can flow.

It is to further advantage that the cereal grain bran before mixing with the oil plant pomace contains 25 - 45 wt% water alternatively, when, before mixing with the oil-plant pomace the water content of the cereal grain bran is first supplemented to be 25 - 45 wt%. The advantage is that the input parameters of the material mixture can thus be optimised with respect to the final product and, in particular, to the production method by which the particular product can be produced.

It is also to advantage that the pressing comprises a first pressing cycle lasting 1s to 30s at a pressure of 1 MPa up to 30 MPa, followed by at least one pressure release lasting 0.5 to 15s, and at least one further pressing cycle lasting 1s to 20s at a pressure of 1MPa up to 30MPa. The advantage of the above press cycle parameters is that they allow the production of quality mouldings with predetermined parameters.

A great advantage is that the heating of the mould, or any part thereof, is variable during the moulding. The advantage again is the optimisation of production conditions for individual pressings with respect to the required parameters of a particular product.

It is to further advantage that after being metered into the mould, the composition is first evenly distributed in the mould, while most advantageously it is subsequently pre-pressed, wherein a pressing preform is created. The advantage is that it is possible, prior to the pressing itself, to create a pressing preform, which will be prepared especially for pressing more complicated shaped mouldings and/or mouldings which are, in respect to pressing, the most complicated, such as, for example flat thin-walled mouldings such as plates.

To advantage, after pressing or firing, the moulding is provided with stamped identification symbols, which may be an image symbol, an alphanumeric symbol, or a combination thereof. The advantage is the possibility of simple moulding stamping with a certain logo or other identification data, without its impairment in terms of ecological disposal.

The main advantage of the moulding and the method of its production according to the invention is that the moulding is easy to press, spatially stable and at the same time resistant to moisture, both in the air and direct, which allows both wide application and at the same time, allows for long-term storability.

Examples of the Performance of the Invention

Example 1

The moulding from biodegradable material, which is a 25cm diameter round plate, containing 85 wt% wheat bran and 15 wt% rapeseed cake, with 15 wt% of the moulding being water structurally bound in the form of moisture.

According to the method for producing the moulding, firstly the water content of the wheat bran is supplemented to be 45 wt%. Then 85 wt% wheat bran is mixed with 15 wt% rapeseed cake, then this mixture is metered into a two-part pressing mould, the whole of which is preheated to 195°C, inside which the mixture is firstly evenly distributed, and inside which the pressing is subsequently carried out.

The pressing includes a first pressing cycle for 20s with a pressure of 10 MPa, followed by a 5s pressure release, and a further pressing cycle is performed for 15s with a pressure of 12 MPa, followed by a 5s pressure release, followed by a pressing cycle of 25s with a pressure of 15 MPa, followed by a 5s pressure release, followed by a pressing cycle for 15s with a pressure of 10 MPa followed by a 5s pressure release, followed by a pressing cycle of 20s with a pressure of 15 MPa, after 1s pressure release, then by stamping the moulding is provided with an identification symbol, which is the manufacturer's logo. This is followed by releasing both parts of the mould and removing the pressed plate. Example 2

The moulding from biodegradable material, which is a square plate with dimensions of 20 x 10cm, containing 80 wt% wheat bran and 20 wt% of rapeseed cake, with 12 wt% of the moulding being water structurally bound in the form of moisture.

According to the method for producing the moulding, firstly the water content of the wheat bran is supplemented to be 38 wt%. Then 80 wt% wheat bran is mixed with 20 wt% rapeseed cake, then this mixture is metered at a normal temperature into a two-part pressing mould in which the mixture is evenly distributed and then pre-pressed for 5s with a pressure of 1MPa, whereby a flat pressing preform is created. Then, the two-piece mould is heated to 185° C, and inside which the pressing is subsequently carried out.

The pressing includes a first pressing cycle for 20s with a pressure of 10 MPa, followed by a 5s pressure release, and a further pressing cycle is performed for 1s with a pressure of 1 MPa, followed by a 2s pressure release, followed by a pressing cycle of 15s with a pressure of 15 MPa, followed by a 2s pressure release, followed by a pressing cycle of 15s with a pressure of 10 MPa, followed by a 1s pressure release followed by a pressing cycle of 15s with a pressure of 15 MPa, followed by a 1s pressure release, then by stamping the moulding is provided with an identification symbol, which is the manufacturer's identification data. This is followed by releasing both parts of the mould and removing the pressed plate.

Example 3

The moulding from biodegradable material, which is a round mug with a diameter of 7cm and a depth of 7cm, containing 70 wt% wheat bran and 30 wt% of flaxseed cake, with 1 wt% of the moulding being water structurally bound in the form of moisture.

According to the method for producing the moulding, firstly 70 wt% wheat bran, containing 25 wt% water, is mixed with 30 wt% flaxseed cake, then this mixture is metered into a three-part mould, in which the mixture is evenly distributed and inside which the pressing is subsequently carried out.

The pressing includes a first pressing cycle for 30s with a pressure of 10 MPa, the temperature of the whole mould being steadily increased to 120°C during the pressing cycle, followed by a pressure release for 2s with the creation of a plate preform, then another pressing cycle is performed wherein, by inserting the pressing core for 15s at a pressure of 12 MPa and with the temperature of the inserted core being 250°C the mug cavity is formed. This is followed by releasing all parts of the mould and removing the pressed mug.

Example 4

The moulding from biodegradable material, which is a saucer with a diameter of 10cm, containing 90 wt% wheat bran and 10 wt% of rapeseed cake, with 10 wt% of the moulding being water structurally bound in the form of moisture.

According to the method for producing the moulding, firstly 90 wt% wheat bran, containing 45 wt% water, is mixed with 10 wt% flaxseed cake then this mixture is metered at normal temperature into a two-part compression mould in which the mixture is first evenly distributed and inside which the pressing is subsequently carried out.

The pressing includes a first pressing cycle for 30s with a pressure of 1 MPa at a temperature of 60°C, followed by a 0.5s pressure release, and a further pressing cycle for 20s at a pressure of 20 MPa at a temperature of 250°C. This is followed by releasing both parts of the mould and removing the pressed saucer.

Example 5

The moulding from biodegradable material, which is a tray for direct food serving food with the dimensions 60x30 cm, containing 85 wt% wheat bran and 15 wt% of rapeseed cake, with 14 wt% of the moulding being water structurally bound in the form of moisture.

According to the method for producing the moulding, firstly the water content of the wheat bran is supplemented to be 25 wt%. Then 85 wt% wheat bran is mixed with 15 wt% rapeseed cake, then this mixture is metered at a normal temperature into a two-part pressing mould in which this mixture is evenly distributed inside the mould and then pre-pressed for 1s with a pressure of 1 Mpa, forming a flat rectangular pressing preform, which is then inserted into the next two-piece moulds, all preheated to 210° C, in which the moulding is subsequently carried out.

The pressing includes a first pressing cycle for 10s with a pressure of 30 MPa, followed by a pressure release period of 15 seconds, and a further pressing cycle is performed for 20s with a pressure of 30 MPa, followed by a 5s pressure release, followed by a pressing cycle for 15s with a pressure of 30 MPa, followed by a pressure release for 5s, followed by a pressing cycle of 20s with a pressure of 20 MPa. Then both parts of the mould are released and the pressed tray is removed.

Example 6

The moulding from biodegradable material, which is an oval bowl with the dimensions 20x15cm, containing 75 wt% wheat bran and 25 wt% of rapeseed cake, with 5 wt% of the moulding being water structurally bound in the form of moisture.

According to the method for producing the moulding, firstly the water content of the wheat bran is supplemented to be 25 wt%. Then 75 wt% wheat bran is mixed with 25 wt% rapeseed cake, then this mixture is metered into a two-part pressing mould, the whole of which is preheated to 60°C, inside which the mixture is firstly evenly distributed, and inside which the pressing is subsequently carried out.

The pressing includes a first pressing cycle for 5s with a pressure of 10 MPa at a mould temperature of 60°C followed by a pressure release period of 15 seconds, and a further pressing cycle of 10s with a pressure of 10 MPa at a mould temperature of 90°C is carried out, followed by a 0.5s pressure release followed by a pressing cycle for 1s with a pressure of 15 MPa at a mould temperature of 210°C, followed by 0.5s pressure release, followed by pressing cycle for 5s at 10 MPa at a mould temperature of 230°C, followed by 1s pressure release, and followed by pressing cycle for 1s with a pressure of 15MPa at a mould temperature of 250°C, after the pressure is released for 1s, then by stamping the moulding is provided with an identification symbol, which is the manufacturer's logo. This is followed by releasing both parts of the mould and removing the pressed bowl.

Example 7

The moulding from biodegradable material, which is a container for food products in the form of a box with the dimensions 20x10x10cm, containing 75 wt% uniform mixture of rye and oat bran and 25 wt% of rapeseed cake, with 10 wt% of the moulding being water structurally bound in the form of moisture.

According to the method for producing the moulding, firstly the water content of the wheat bran is supplemented to be 42 wt%. Then 75 wt% mixture of rye and oat bran is mixed with 25 wt% rapeseed cake, then this mixture is metered into a two-part pressing mould, the whole of which is preheated to 250°C, inside which the mixture is firstly evenly distributed, and inside which the pressing is subsequently carried out.

The pressing includes a first pressing cycle for 1s with a pressure of 20 MPa, followed by a 5s pressure release, and a further pressing cycle is carried out for 2s with a pressure of 10 MPa, followed by a 5s pressure release, followed by a pressing cycle of 1s with a pressure of 15 MPa, followed by a pressure release for 5s, followed by a pressing cycle for 5s with a pressure of 10 MPa. This is followed by releasing both parts of the mould and removing the moulded container.

Example 8

The moulding from biodegradable material, which is a baking form for baking bread from bread mix with the dimensions 28x12x12cm, containing 95 wt% wheat bran and 5 wt% of olive pomace, with 8 wt% of the moulding being water structurally bound in the form of moisture.

According to the method for producing the moulding, firstly the water content of the wheat bran is supplemented to be 45 wt%. Then 95 wt% wheat bran is mixed with 5 wt% olive pomace, then this mixture is metered into a two-part pressing mould, the whole of which is preheated to 80°C, inside which the mixture is firstly evenly distributed, and inside which the pressing is subsequently carried out.

The pressing includes a first pressing cycle for 30s with a pressure of 5 MPa at a mould temperature of 90°C, followed by a 2 second pressure release, and a further pressing cycle for 20s at a pressure of 20 MPa at a mould temperature of 150°C.

Industrial Application

The moulding and the method for its production according to the invention can be used to efficiently process bran, with the mouldings being universally applicable, preferably for tableware and various food containers, with subsequent biodegradability, for example, as feed for farm animals.