DE9310182U1 - Molding from various fractions of plastic waste products - Google Patents

Description

ry 2145a/93 2 July 1993

Description:

The invention relates to a molded part made of different fractions of thermoplastics as well as a method and a device for its production.

From DE-OS 24 02 976 a construction material made of a mixture of thermoplastics and at least one filler is known, which is characterized in that the mixture contains as components at least thermoplastics and at least one filler of mineral and/or organic type, wherein the filler(s) make up at least the same proportion by weight of the total weight of the mixture as the thermoplastics.

Fillers include wood chips, wood flour, asbestos dust, asbestos fibers, peat, sulfur, silica, sand, graphite, metal chips, ash from waste incineration plants, waste from thermosetting plastics. As far as inorganic fillers are concerned, experience in the past has shown that these lead to inhomogeneous construction materials with low breaking strength. With wood chips and wood flour there is a risk of ignition during the manufacturing process.

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Asbestos dust and asbestos fibers could not be bound in such a way that they would not leach into the atmosphere. Waste from thermosetting plastics, on the other hand, requires additional heating as a filler, as it must harden under the influence of heat. To our knowledge, none of these construction materials has yet been manufactured or used in any other way.

The process disclosed in DE-OS 24 02 976 also gives no concrete indication of how the plastics mentioned therein are to be converted into which product using which process. On the one hand, at the temperatures disclosed therein of 240 ⁰ C to 300 ⁰ C for mixing plastic mixtures and fillers, there is a risk of the fillers catching fire because they are also supposed to consist of wood chips and other easily flammable material, and on the other hand, it is not specifically explained how and in what way finished products are to be made from them. It is important that most plastic processing processes cannot be used for inhomogeneous products of this type, such as extrusion, extrusion molding, calendering, etc., and other processes require a blowing agent, which is not disclosed in this publication.

DE-OS 24 44 420 discloses a construction material made of a mixture, which contains as components thermoplastics made of at least one filler of mineral and/or organic type, whereby the filler is to have a coating made of silicate material, in particular sodium silicate. Other fillers

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July 2, 1993

wood chips, wood flour, asbestos dust, asbestos fibres, peat, sulphur, silica, sand, graphite, metal chips, ash from

Waste incineration plants, waste from thermosetting plastics are offered. The fillers are to be heated, mixed and coated in a pre-mixer before being mixed with a plastic component. This mixing and coating is to take place in a mixer in a vacuum at a temperature of 70 ⁰ C to 100 ⁰ C. No products are known to have been produced using this complex process. This is also likely to be difficult because the mixture disclosed there by means of extruded strands, even if they enter a mold, always has cavities of varying sizes after the material has been mixed, since there is no blowing agent.

According to the disclosure content of this DE-OS 24 44 420, the mixing in the mixer should take place under vacuum and with the addition of an inert, neutral gas. The inert gas in the mixer only has the function of creating a kind of neutral external atmosphere without an infiltration effect in the mixture. Accordingly, the product contained therein must have a relatively high porosity and correspondingly poor strength properties. Leaching of the contaminants contained therein cannot be guaranteed due to the unsealed capillary paths.

Based on this state of the art, the invention is based on the object of creating a molded part of the type mentioned at the beginning, which is cost-effective without additional fillers

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is composed exclusively of waste products, excludes leaching of its core area and nevertheless, as a finished product, guarantees a surprisingly high thermal load capacity as well as pressure, bending and acid resistance.

This object is achieved according to the invention in that it consists of a thermoplastically heatable, foamable with a blowing agent, pressed into an injection mold, provided with ventilation openings and cooled by air molded block made from a mixture of sorted plastic waste from the waste industry (dual system) and fillers from plastic carpet residues and/or waste residues from sanitary products with cellulose, such as diaper pants or the like, which has a denser structure in its edge areas than in its core area. Such a molded block showed no water absorption or leaching tendencies even after a cooking process of five hours and no deformation under a pressure load of five tons. After drop tests from a height of ten meters, no deformation or splintering could be detected. The same result was seen after storage for three days at -18 ⁰ C. Oils, petrol or other hydrocarbons and even acids could not penetrate the molded bricks because the polyethylene and polyamides they contain, which have a particularly dense structure in their edge areas, are acid-resistant. Using the molded bricks as interlocking bricks in a factory driveway under daily load from trucks, forklifts and people did not lead to any deformation and/or displacement.

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According to a first embodiment, the molded piece consists of a cuboid-shaped molded stone in the form of a composite stone with a size of 200 mm x 100 mm x 60 mm and a weight of approx. 840 g. As a composite stone, it can be provided with a rectangular, square or polygonal tread surface and can have a zigzag or wavy shape perpendicular to its tread surface.

According to another alternative, the shaped stone is formed in the form of a circular ring with a concave section.

According to advantageous further developments, the shaped piece is designed as a lattice stone with uniform square openings in a row or diagonal arrangement.

In order to be able to arrange and consolidate all the shaped stones in a composite, they are provided with molded spacer strips on their side edges, which extend almost over the entire height of the shaped stone and have either a rectangular or circular cross-section shape. This means that the joints between the individual shaped stones can be filled with standard sand or other inorganic filling materials and consolidated so that they can drain.

To avoid point loads and possible splintering, each shaped stone is provided with a 45° bevel on its surface edge, approximately 6 mm to 10 mm wide.

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To increase the slip resistance of its tread surface and to improve its appearance, the molded stone is provided with grooves and ridges on its tread surface, which are either symmetrical or asymmetrical or form figurative patterns of geometric shapes, such as hexagons, triangles, squares, other polygons or ornamental objects, such as flower rosettes or the like.

The particular advantage of this molded stone is that it is made exclusively from freely available waste products and does not require any additional organic or inorganic materials as fillers, such as sodium silicates or similar, which make its production more expensive and reduce its strength properties. A particular advantage of the new molded stone is, on the one hand, its rough surface structure and, on the other hand, its ability to be used as a fully usable product without any signs of collapse for the composite stones previously made from inorganic materials.

According to a particularly advantageous development of the invention, the molded stone consists of sorted plastic waste from the waste industry as well as cellulose and/or plastic carpet residues, which are ground to a maximum grain size of 10 mm and then in the following alternative weight percentages

a) 50% to 60% sorted plastics from household waste (dual system) 40% to 50% from plastic carpet scraps with polyamides, acrylics, adhesives, rubber and foam or

b) 50% to 60% sorted plastics from household waste (dual system), 40% to 50%

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Waste residues from the manufacture of sanitary products, such as diaper pants, panty liners, bed pads, etc., with cellulose, polyethylene film and moisture-binding polyacrylate or

c) 50% to 60% sorted plastics from household waste (dual system), 20% to 25% plastic carpet residues with polyamides, acrylics, adhesives, rubber and foam and 20% to 25% waste residues from the manufacture of sanitary products, such as diaper pants, panty liners, bed pads etc., with cellulose, polyethylene film and moisture-binding polyacrylate, can be mixed with one another, whereby the mixture contains a residual moisture of 5% to 10% as a blowing agent and after heating to approx. 150 ⁰ C in a foamed state can be pressed into an injection mold and after demolding the residual moisture which inflates the molded block can largely be vented through the ventilation openings.

Such a molded block has a much denser structure in its outer cross-sectional edge areas than in its core. This is because the residual moisture of 5% to 10% contained in the mixture is used as a blowing agent, which means that after heating to 150 ⁰ C, the mixture can be pressed into an injection mold in a foamed state. Surprisingly, the easily flowing materials, such as polyethylene and polyamide, appear to get into the edge areas of the molded block under the pressure of the residual moisture as a blowing agent, where they form a sealing, protective and mechanically highly resilient wall around the considerably coarser-grained core area. Without this residual moisture and thus without a blowing agent, such injection molded products show considerable collapse phenomena, which make them

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This makes finished products appear unsuitable, for example in the construction industry.

After the mold has been drawn, the molded part has a bloated, convex shape in the large surface areas. This - unwanted - shape is caused by the propellant of the residual moisture. By providing the vent openings in the injection molded part, this residual moisture is vented. After this, the molded part once again takes on the desired surface shape according to the injection mold. The molded part is then exposed to atmospheric air and, once its core has cooled, can be used immediately as a finished product.

The inventive molded stone allows its mixture and thus also itself to contain 3% of contaminating metals in the form of foil closures, cup lids or the like.

The plastic carpet residues contained in the molded block are essentially made up of around 80% polyamide, 17% rubber and 3% adhesive or 78% to 80% polyamide, 20% to 22% acrylic and 3% to 5% foam. The different compositions are due to the overall height, in particular the height and density of the polyamide floor.

The pulp that is still molded into the mold consists of pulp residues from the sanitary industry production of sanitary towels, bed pads, tampons, diaper pants, panty liners or operating table covers, which contain approx. 60% to 70% pulp, 27% to 37% polyethylene film and approx. 3%

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contain moisture-binding polyacrylate.

The plastic waste that makes up the majority of the molded parts comes from the waste industry of the "Dual System" (Green Dot), which essentially consists of high and low-pressure polyethylene films, high and low-pressure polyethylene and polypropylene containers, and polypropylene and polypropylene cups.

The finished mixture is pre-dried to a moisture content of 5% to 10%, based on the dry substance, with a grain size of maximum 10 mm. It can be heated to approx. 150 ^° C in an injection molding machine and the foamed, plastic molding compound that results after heating can be injected into molds using an injection molding machine. It is important that the entire material is foamed, which is achieved by using the residual moisture of 5% to 10% as a blowing agent.

In order to give the molded parts an attractive appearance, the mixture of the fractions used is colored with a dye before pre-drying in the mixer. This dye can cover the entire color palette from white, concrete gray, brick red to black.

The previously known devices and methods according to DE-OS 24 02 970 and DE-OS 24 44 420 do not disclose any crushing device or any measure for using a propellant. As a result, the product manufactured according to the different methods can only have very different inhomogeneities and very different collapse phenomena.

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be.

The invention is explained in more detail below using a device for producing the molded parts according to the invention and using different shapes of molded blocks. Shown are:

Fig. 1 shows a device for producing

Moulded parts with a dosing device, a mill, a mixer, a pre-drying device, a
Injection moulding machine with carousel-like injection moulds and a piercing device,

Fig. 2 to 4 the top and side view in

direction of arrow IM and the front view of a cuboid shaped piece in the direction of arrow IV of Fig. 1,

Fig. 5 and 6 the top view and the side view in the direction of arrow Vl of Fig. 5 of a composite stone with a square tread and cross-shaped grooves,

Fig. 7 and 8 the top view and the side view in the direction of arrow VIII of Fig. 7 of a hexagonal shaped brick,

Fig. 9 and 10 the top view and side view in the direction of arrow X of Fig. of a square shaped brick,

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Fig. 11 to 13 the top, side and

Front view in the direction of arrows XII and XIII of Fig. 11 of a shaped stone in the form of a circular ring with a concave section,

Fig. 14 to 16 one to its tread

zigzag-shaped shaped brick in plan view as well as in side and front view in the direction of arrows XV and XVI of Fig. 14,

Fig. 17 and 18 the top view and the

Side view in the direction of arrow XVIII of Fig. 17 of a grid-shaped molded stone with a rectangular passage opening,

Fig. 19 to 21 the top view and the side

and front view in the direction of arrows XX and XXI of Fig. 19 of a molded brick designed as a lattice brick with uniform square openings in a row arrangement, and

Fig. 22 and 23 show the top view and side view in the direction of arrow XXIII of Fig. 22 of a shaped brick designed as a lattice brick with uniform square openings in a diagonal arrangement.

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According to Fig. 1, the device 1 for producing the molded parts according to the invention consists of a metering device 2, a mill 3, a mixer 4, a pre-drying device 5, an injection molding machine 6 with heating device 7 and nozzle 8, to which the carousel-like injection molds 9 are assigned, followed by a chute 10 with piercing device 11.

Conveyor belts 12, 13 are arranged between the dosing device 2 and the mill 3 as well as between the mill 3 and the mixer 4, which can also be replaced by slides if arranged at different heights.

Between mixer 4 and the

Additional conveyor belts 14, 15 are arranged between the pre-drying device 5 and the injection molding machine 6. These can also be replaced by appropriate slides if necessary.

The dosing device 2 removes the sorted plastic waste stored in the containers 16 to 18 with the appropriate mixing ratio, from which it is transported to the mill 3 via the conveyor belt 12. The following three mixing alternatives are possible:

According to a first mixing alternative, for example, 50% to 60% (percent by weight) of sorted plastics from household waste according to the "Dual System" of the "Green Dot" are used for the molded part from container 16 and 40% from container 17.

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up to 50% (by weight) from plastic carpet residues containing polyamides, acrylics, adhesives, rubber and foam.

According to a second mixing alternative, the ingredients for the molded stone are mixed with cellulose, polyethylene film and moisture-binding polyarylate from container 16, for example 50% to 60% (by weight) of sorted plastics from household waste according to the "Dual System" and from container 18, for example 40% to 50% (by weight) of waste residues from the manufacture of sanitary products, such as diaper pants, panty liners, bed liners, etc.

According to a third mixing alternative, for example, 50% to 60% (by weight) of sorted plastics from the household waste of the "dual system" are taken from the container 16 for the molded part, 20% to 25% (by weight) of plastic carpet residues with polyamides, acrylics, adhesives, rubber and foam are taken from the container 17, and 20% to 25% (by weight) of waste residues from the manufacture of the aforementioned sanitary products are taken from the container 18 and transported to the mill 3 via the conveyor belt 12.

In the mill 3, which can consist of a knife mill, for example, the above-mentioned plastics are reduced to a grain size of a maximum of 10 mm. The plastic waste reduced in size in this way is transported via the conveyor belt 13 to the mixer 4, in which a homogeneous mixture is produced. This homogeneous mixture is then transported via the conveyor belt 14 to the pre-drying device 5.

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In this, pre-drying takes place in such a way that the mixture only contains a residual moisture content of 5% to 10% based on its dry matter. This residual moisture is subsequently required as a propellant.

After the homogeneous mixture pre-dried in this way reaches the injection molding machine 6 via the conveyor belt 15, it is heated via the heating device 7, which can consist, for example, of a heated, double-walled cylinder, and is pressed by the press screw 19 in a foamed, heated state as a plastic mass through the nozzle into an injection mold 9.

In Fig. 1, there is a carousel 20 in front of the injection molding nozzle 8, which is equipped with several injection molds 9, 9a, 9b, 9c and rotates in the direction of the arrow 21 in discontinuous time cycles of, for example, 20 seconds to 30 seconds, so that the injection mold 9a shown takes up the position of the injection mold 9c after one cycle and the following injection mold 9b comes in front of the injection molding nozzle 8. During the interval-wise pivoting process of the individual injection molds 9, 9a, 9b, 9c in the direction of the arrow 21, the cooling process of the molded part 22 in the mold takes place. As soon as an injection mold 9 has reached the position of the injection mold 9b, the mold is pulled and the molded part falls onto the chute 10, which has a cross-section that narrows downwards. This allows the molded part 22 to slide down the chute 10 under its gravity component until it hits a limit switch 23, which then

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The piercing device 11 with the two piercing needles 11a and 11b is activated and the molded piece 22 is pierced from two sides. These piercing openings form the vent openings of the molded stone. The water vapor/air mixture contained primarily in the core can then escape through these vent openings in the relatively dense structure in the outer edge area of the cross-sectional shape of a molded piece, and the molded piece 22 can therefore assume its original, flat outer surface shape corresponding to the injection molds. No collapse phenomena could be detected in tests.

When the carousel 20 is pivoted in conjunction with the injection molds 9, 9a, 9b, 9c, the nozzle remains closed by a closure (not shown).

A first embodiment of a shaped block 24 is shown in Figs. 2 to 4. This cuboid shaped block 24 has the shape of a composite block with a size of 200 mm x 100 mm x 60 mm and a weight of approximately 840 g. Depending on the mixture alternatives, the weight can vary between 800 g and 900 g in this size range. On the side edges 25, 26, this shaped block is provided with spacer strips 27 which extend almost over its entire height H and have either a rectangular shape or, as shown, a circular segment shape in cross section. On its surface edges 28, the shaped block 24 is provided with a circumferential edge bevel 29 which runs at approximately 45° and is approximately 6 mm to 10 mm wide.

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The spacer strips ensure a gap between two adjacent composite stones 24 for filling and consolidation with conventional building materials when laying these shaped stones. On its underside, the shaped stone 24 has a dome-like depression 30, which is caused by the injection mold.

In the embodiment of Fig. 2, the tread surface 31 is rectangular. However, it can be square, as in the embodiments of Figs. 5 and 9. Thus, the shaped stone 32 according to Figs. 5 and 6 is provided with a square tread surface 33, into which grooves or grooves 34, 35 are cut crosswise to increase the slip resistance, resulting in four smaller square surfaces 36. Both the square shaped stone 32 according to Figs. 5 and 6 and the shaped stone 37 according to Figs. 9 and 10 are provided with the same edge bevels 29 of the shaped stone 24.

In the embodiment of Fig. 7 and 8, the shaped stone 38 is designed with an octagonal tread surface 39 and has the same edge bevels 29 as the shaped stones 24 and 32 according to Fig. 2 to 5. It is understood that the tread surface 30 of this shaped stone can also be hexagonal, triangular, polygonal and even circular.

In Fig. 11 to 13, a lattice stone 40 is shown in the form of a circular ring with a concave ring section. The peripheral edge bevels 29, 42 on the outer and inner circumference of this lattice stone correspond to those in Fig. 2 to 10. It is understood that a lattice stone with the same

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External configuration in the form of a closed circular disk with a concave circular section can be produced. In this case, the inner edge bevel 42 would be omitted and the entire tread area would be completely filled with material. Fig. 12 shows the view of the shaped stone 40 in the direction of the arrow XII of Fig. 11 and Fig. 13 shows the view of the shaped stone 40 of Fig. 11 in the direction of the arrow XIII.

In Figs. 14 to 16, a lattice stone 44 with a zigzag-shaped tread surface 45 is shown, which is also provided with a peripheral edge bevel 29. The zigzag-shaped side areas 46 can also be corrugated. Fig. 15 shows the shaped stone 44 in the direction of arrow XV of Fig. 14 and Fig. 16 shows the front view along arrow XVI of Fig. 14.

Fig. 17 and 18 show a rectangular lattice stone 47 with a rectangular opening 48 and a bevel 29 running around the inside and outside edges. Fig. 18 shows the lattice stone 47 of Fig. 17 in the direction of arrow XVIII of Fig. 17.

Fig. 19 to 21 show a grid block 49 with square grid openings 50 arranged in rows and with molded-on spacer strips 51 with a rectangular cross-sectional shape. Fig. 20 shows the grid block in the direction of arrow XX and Fig. 21 in the direction of arrow XXI of Fig. 19.

Fig. 22 and 23 show a lattice stone 52 with uniform square openings 53 in a diagonal arrangement. Fig. 23 shows the view in

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Direction of arrow XXIII of Fig. 22.

To increase the slip resistance of the visible tread surface 31, 33, 39, 45, the shaped stones 24, 32, 37, 38 and 44 can not only be provided with the grooves or grooves 34, 35 of Fig. 5 and 6, which are either symmetrical or asymmetrical, but also with figurative patterns of geometric shapes, such as hexagons, triangles, squares or other polygons or with ornaments such as flower rosettes. In addition to an attractive color, the shaped stone also receives an attractive external appearance of its tread surface through the coloring of the respective mixtures.

The molded part according to the invention can be produced with 100% waste material without additional non-waste materials as filler and can be used not only as filling material but also as an attractive building material, e.g. for paving paths, roads and other surfaces, which is characterized by high mechanical and thermal resilience as well as resistance to acids and bases.

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List of reference symbols:

Device 1

Dosing device 2

Mill 3

Mixer 4

Pre-drying device 5

Injection molding machine 6

Heating device 7

Nozzle 8

Injection molds 9, 9a, 9b, 9c

Slide piercing device

Piercing needles 11a, 11b

Conveyor belts 12, 13, 14,

Containers 16, 17,

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2 July 1983

Press screw 19

Carousel 20

Direction arrow 21

Fitting 22

Limit switch 23

Formstone 24, 32, 37, 42,

44, 49,

Side edges of the shaped stone 24 25,

Spacer strips of the shaped stone 24 27

Height of the shaped stone 24 H

Surface edges of the shaped stone 24 28

Edge bevel of the shaped stone 24 29

dome-like depression

of the shaped stone 24 30

Treads of the

Shaped bricks 24, 32, 38 31, 33,

Grooves/Striations 34,

square areas 36

Lattice stones 40, 47, 49,

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concave ring section 41

inner edge bevel 42

Tread area of lattice stone 40 43

Side areas of the shaped stone 44 46

rectangular opening 48

square openings 50

Spacer strips of the shaped stone 49 51

Direction arrows III, IV, Vl,

XIII, XV, XVI, XVIII, XX, XXI, XXIII

Claims (19)

ry. 2T45a/93 2 July 1993 Protection claims: 1. Moulded part made from various fractions of waste products of thermoplastics, characterised in that it consists of a thermoplastically heatable, foamable with a blowing agent, pressable into an injection mould (9, 9a, 9b, 9c) and provided with ventilation openings and a cooled by air Molded brick (24, 32, 37, 38, 40, 44, 47, 49, 52) made of a mixture of sorted plastic waste from the waste industry (dual system) as well as fillers from plastic carpet residues and/or waste residues from sanitary products with cellulose, such as diaper pants or the like, which has a denser structure in its edge areas than in its core area. 2. Moulded piece according to claim 1, characterized in that it consists of a cuboid-shaped moulded stone (24) in the form of a composite stone with a size of 200 mm x 100 mm x 60 mm and a weight of approximately 840 g. Page 2 ry-2145e/93 July 2, 1993 3. Moulding according to claim 1, characterized in that it is designed as a composite stone (24, 32, 37) with a rectangular, square or polygonal tread surface (31, 33, 35). 4. Moulding according to claim 1, characterized in that it consists of a zigzag-shaped or corrugated moulded stone (44) or composite stone perpendicular to its tread surface (45). 5. Shaped piece according to claim 1, characterized in that it is formed from a shaped block (40) in the form of a circular ring with a concave section (41). 6. Mouldings according to claim 1, characterized in that it is designed as a lattice block (49, 52) with uniform square openings (50, 53) in a row or diagonal arrangement. 7. Moulding according to one of claims 1 to 6, characterized in that the moulded blocks (24, 49) are provided with moulded-on spacer strips (27, 51) on their side edges. 8. Moulded piece according to claim 7, characterized in that the spacer strips (27, 51) extend almost over the entire height (H) of the moulded block (24, 32, 37, 45) and have either a circular segment shape or a rectangular shape in cross section. Page 3 ry 2145a/93 July 2, 1993 9. Moulded piece according to one of claims 1 to 8, characterized in that the moulded stone (24, 32, 37, 38, 40, 44, 47) is provided on its surface edges with a peripheral edge bevel (29) running at 45° and approximately 6 mm to 10 mm wide. 10. Moulded piece according to one of claims 1 to 9, characterized in that it is provided on its tread surface (31, 33, 35) with grooves and grooves (34, 35) which increase its slip resistance and which run either symmetrically or asymmetrically or form figurative patterns of geometric shapes, such as hexagons, triangles, squares, other polygons or ornamental objects, such as peonies or the like. Page 4 ry 2145a/93 July 2, 1993 11. Moulding according to one of claims 1 to 10, characterized in that it consists of sorted plastic waste from the waste industry as well as cellulose and/or plastic carpet residues, which are ground to a maximum grain size of 10 mm and then in the following alternative weight percentages a) 50% to 60% sorted plastics from household waste (dual system) 40% to 50% from plastic carpet scraps with polyamides, acrylics, adhesives, rubber and foam or b) 50% to 60% sorted plastics from household waste (dual system), 40% to 50% waste residues from the manufacture of sanitary products, such as diaper pants, panty liners, bed pads, etc., with cellulose, polyethylene film and moisture-binding polyacrylate or c) 50% to 60% sorted plastics from household waste (dual system), 20% to 25% plastic carpet residues with polyamides, acrylics, adhesives, rubber and foam and 20% to 25% waste residues from the manufacture of sanitary products, such as diaper pants, panty liners, bed pads etc., with cellulose, polyethylene film and moisture-binding polyacrylate, are mixable with each other, whereby the mixture contains a residual moisture of 5% to 10% as a blowing agent and after heating to approx. 150 ⁰ C in a foamed state can be pressed into an injection mold and after demolding the residual moisture can be largely vented through the ventilation openings of the molded part. Page 5 ry 2145a/93 July 2, 1993 12. Moulded part according to one of claims 1 to 11, characterised in that the mixture contains a maximum of 3% by weight of metals in the form of foil closures, cup lids or the like as impurities. 13. Moulded piece according to one of claims 1 to 12, characterized in that the plastic carpet residues contained therein are composed of approximately 80% polyamide, 17% rubber coating and 3% adhesive or of 78% to 80% polyamide, 20% to 22% acrylic and 3% to 5% foam. 14. Moulded part according to one of claims 11 to 13, characterized in that the celluloses moulded into it consist of pulp residues from the sanitary industry production of sanitary towels, bed pads, tampons, diaper pants, panty liners or operating table covers, which contain approx. 60% to 70% cellulose, 27% to 37% polyethylene film and approx. 3% moisture-binding polyacrylate. 15. Moulded part according to one of claims 1 to 14, characterized in that the plastic waste from the waste industry (dual system) contained therein is composed of films of high and low-pressure polyethylene, of containers of high and low-pressure polyethylene and polypropylene and of cups of polypropylene and polystyrene. Page 6 ry 2145a/93 July 2 &Idigr;993 16. Moulding according to one of claims 1 to 15, characterized in that the finished mixture with a grain size of maximum 10 mm with a moisture content of 5% to 10%, based on the dry substance, can be heated to approximately 150 ^° C in an injection moulding machine and the foamed, plastic moulding compound resulting after heating can be injected into moulds by means of an injection moulding machine. 17. Moulded part according to one of claims 1 to 16, characterized in that the moulded parts are provided with ventilation openings after their shape has been drawn by piercing to allow the water vapours to escape. 18. Moulding according to one of claims 1 to 17, characterized in that the mixture of the fractions used in each case is coloured with a dye before pre-drying in the mixer. 19. Moulding according to one of claims 1 to 18, characterized in that after the mould has been drawn, the moulding is cooled by atmospheric air.