Methods and apparatus for manufacturing solid foam, products and uses

Abstract

This application relates to a method and apparatus for continuously producing solid foam. A homogeneous suspension is formed from raw materials, the suspension including a coagulant, and a foam mixture containing gas bubbles is formed by mixing the gas bubbles into the suspension. The foam mixture is sprayed through at least one nozzle to form a foam pattern, the foam pattern is placed on a moving surface, and the foam mixture in the foam pattern is allowed to solidify to form a solid foam, with the gas bubbles in the foam mixture shrinking off-axis to form shaped gas bubbles. Furthermore, this application relates to uses of the product and method.

Description

Technical Field

[0001] This application relates to the method defined in claim 1 and the apparatus defined in claim 11 for continuously manufacturing a solid form. Further, this application relates to the use of the product defined in claim 16 and the method defined in claim 18. Solid forms such as bio-based solid forms can be manufactured, and products can be manufactured from solid forms.

Background Art

[0002] The production of bio-based solid forms by the liquid form route has emerged as a promising method for obtaining new lightweight materials. Currently, the foams produced using this route have an isotropic structure due to slow drying in a high-temperature environment, which also tends to simultaneously relax the bubble shape. In many applications, lightweight materials with properties such as high strength on the one hand and good heat conduction like wood on the other hand are advantageous. In particular, heat insulation in such anisotropic structures is superior compared to their isotropic counterparts.

[0003] One method for manufacturing anisotropic foams uses freeze casting, for example, Lavoine, N & Bergstroem, L (2017), Nanocellulose-based foams and aerogels: processing, properties, and applications, Journal of Materials Chemistry A, 5(31), 16105 - 16117, in which case first the bubbles are elongated by high pressure and then the foam is frozen using a cryogenic gas. After freezing, the pressure is reduced and the moisture is sublimated from the foam while leaving its structure intact. This method is quite expensive due to the machinery required for high pressure and the energy consumption for freezing.

[0004] Porous materials of cellulose fibers and gluten are known from WO2020011587A1. This application describes a method for producing a rigid, biodegradable, isotropic foam having a hydrophobic structure.

[0005] Methods for forming fibrous products are known from WO2015036659A1. Continuous roll-to-roll processes produce thin or bulky paper-like sheets. Here, fiber formation focuses on mold casting and continuous processes that do not scale up. In addition, it is asserted that the foam is an isotropic mixture, neither anisotropic nor elongated. Therefore, the foam does not have significant orientation-dependent strength differences.

[0006] Insulating panels are known from US10,357,936. In insulating panels, a protective cover layer and an insulating layer are bonded together.

[0007] Furthermore, a modification of particle-stabilized fluid-fluid interface is known from US20110111998A1, a tubular film manufacturing apparatus is known from JP5254982B2, a silver nanowire conductive ink for screen printing is known from CN201810602082A, a composition comprising an internal phase dispersed in a hydrophilic continuous phase is known from US9789456B2, an absorbent structure that expands differently is known from US7799967B2, a flame-retardant wood-plastic composite is known from US979034B2, a process for producing cellular cavities in thermoplastic materials is known from US4104207A, in which a medium that forms bubbles is bonded to a carrier, a molded nanoporous body is known from US20190022623A1, and a base material, its manufacturing method and use are known from EP2114645B1. [Overview of the Initiative] [Means for solving the problem]

[0008] The methods, apparatus, products, and uses are characterized by those described in the claims. A method and apparatus for continuously producing solid foam, wherein a suspension is formed from raw materials, a foam mixture is formed from the suspension, and the foam mixture is sprayed and solidified to produce solid foam.

[0009] A method for continuously producing a solid foam includes the steps of: forming a homogeneous suspension from raw materials, wherein the suspension comprises a coagulant; forming a foam mixture containing bubbles by mixing bubbles into the suspension; and injecting the foam mixture through at least one nozzle, such as through at least one nozzle, to form a foam pattern; placing the foam pattern on a moving surface; and solidifying the foam mixture of the foam pattern to form a solid foam such that the bubbles in the foam mixture contract and deform in the off-length direction, thereby forming molded bubbles. The contraction and deformation processes of the foam mixture and bubbles may occur between the nozzle and the moving surface during the injection of the foam mixture and / or during solidification, in relation to the nozzle. In one embodiment, an anisotropic solid foam is formed.

[0010] Anisotropy may be utilized for its superior thermal and mechanical properties in solid foam materials. Anisotropic solid foams have been difficult to prepare due to their fundamental foam physical properties, which cause the cellular shape to relax to an isotropic shape immediately after the removal of external stress. In the production of bio-based foams from a wet state, this occurs during the drying process. Therefore, the preparation of bio-based anisotropic foams requires complex and non-scalable methods such as freeze-drying. This invention includes a method for producing anisotropic foam in a continuous roll-to-roll process that allows for scalability to mass production.

[0011] An apparatus for continuously producing solid foam may include at least one mixer for forming a homogeneous suspension from raw materials, wherein the suspension contains a coagulant; at least one former for forming a foam mixture containing bubbles by mixing bubbles into the suspension; at least one nozzle for spraying the foam mixture to form a foam pattern; a moving surface on which the foam pattern is placed; and at least one solidification device for solidifying the foam mixture of the foam pattern so that the bubbles in the foam mixture contract and deform in the off-length direction to form molded bubbles, thereby forming a solid foam. The contraction and deformation processes of the foam mixture and bubbles may occur between the nozzle and the moving surface during the spraying of the foam mixture and / or at the nozzle during solidification.

[0012] In one embodiment, bubbles in the foam mixture can contract in the off-length direction to form elongated bubbles, such as elongated rod-shaped bubbles. In one embodiment, bubbles in the foam mixture can contract in the off-length direction to form disc-shaped bubbles, such as disc-shaped or penny-shaped bubbles. Bubble shaping can be performed in relation to the nozzle between the nozzle and the moving surface during the spraying of the foam mixture, during solidification or drying, or a combination thereof. In one embodiment, the spraying of the foam mixture through the nozzle and the placement of the foam mixture on the moving surface affect bubble shaping.

[0013] Any suitable raw material can be used in the method and apparatus. In one embodiment, the raw material is a bio-based material. In one embodiment, the raw material is a bio-based material selected from the group consisting of biomass, bio-based residues, wood, wood-based materials, forest-based materials, cellulose, treated bio-based materials, untreated bio-based materials, or combinations thereof. In one embodiment, the raw material includes a coagulant. In one embodiment, the coagulant is added to the raw material and / or suspension. In one embodiment, the coagulant includes plastics, metals, and / or other components having a melting point. In one embodiment, the raw material includes fibers. In one embodiment, a solid fiber material is added to the raw material and / or suspension. In one embodiment, a chemical such as a coagulant is added to the suspension. In one embodiment, a chemical that reduces surface tension, increases viscosity, and promotes coagulation is added to the suspension. In one embodiment, a solvent, such as water or xylene, is added to form the suspension.

[0014] In one embodiment, the apparatus includes at least one addition device for adding a chemical, a solid fiber material, and / or a solvent to a suspension.

[0015] In one embodiment, the chemical is one of methylcellulose, carboxymethylcellulose (CMC), a photopolymer, or a combination thereof. In one embodiment, the chemical is one of methylcellulose, a derivative of methylcellulose, carboxymethylcellulose (CMC), hydroxypropylcellulose, ethylcellulose, etc., or a combination thereof. In one embodiment, the chemical is methylcellulose, its derivatives, nanocellulose, microcellulose, and combinations thereof. In one embodiment, the chemical is carboxymethylcellulose (CMC). In one embodiment, the chemical is a photopolymer. The selected chemical is used as a coagulant, and furthermore, the chemical can be used as a rheomodifying agent, a surfactant, and / or a fiber material. In one embodiment, the surfactant is added to the suspension.

[0016] In one embodiment, the fibers in the raw material or suspension include carbon fibers, carbon nanotubes, graphene, carbon mesh, laponite, hemp fibers, expanded polystyrene, polystyrene, polymers, polymer sticks, yarns, and combinations thereof. In one embodiment, the solid fibrous material added to the raw material and / or suspension is selected from the group consisting of carbon fibers, carbon nanotubes, graphene, carbon mesh, laponite, hemp fibers, expanded polystyrene, polystyrene, polymers, polymer sticks, yarns, and combinations thereof. If the suspension contains fibers, the fibers of the raw material and / or solid fibrous material may be oriented according to molded bubbles, such as elongated bubbles.

[0017] In one embodiment, the apparatus includes two or more nozzles, for example, at least two nozzles. In one embodiment, a foam mixture is sprayed through the nozzles to form a foam pattern.

[0018] In one embodiment, the foam mixture is processed by an extruder, and the foam mixture is ejected from the extruder onto a moving surface. In one embodiment, the foam mixture is formed in the extruder. In one embodiment, the apparatus includes at least one extruder, which includes at least one nozzle.

[0019] Form patterns can be formed by pressing. In this context, pressing means any pressing, injection molding, extrusion, etc., or a combination thereof. In one embodiment, the pattern is formed by extrusion. For example, in extrusion, shears can be formed to form bubbles.

[0020] The moving surface can be any moving device, such as a moving plate, conveyor, belt, etc., or a combination thereof. In one embodiment, the moving surface moves linearly. In one embodiment, the moving surface moves at a speed of 0.1 mm / s to 50 m / s.

[0021] In one embodiment, the foam mixture is solidified by heat, photocatalysis, crosslinking, freezing, or a combination thereof. In one embodiment, the foam mixture is solidified by heat, thereby utilizing radiant heat, conductive heat, and / or convective heat in the solidification process. The foam mixture can be dried during or before / after solidification.

[0022] In one embodiment, the solidification apparatus includes at least one heater for solidifying a foam mixture by heat, thereby using radiant heat, conductive heat and / or convective heat. In one embodiment, the apparatus includes at least one radiant heater as a heater. In one embodiment, the apparatus includes at least one oven as a heater. In one embodiment, the apparatus includes at least one heated moving plate as a heater. In one embodiment, the moving plate is a hot plate, and solidification is performed by the hot plate and the radiant heater.

[0023] In one embodiment, the foam mixture is caused to solidify at a temperature of 1 to 90 °C. In one embodiment, the foam mixture is caused to solidify at a temperature of 30 to 90 °C.

[0024] In one embodiment, the apparatus includes at least one rheomodifier for changing the rheological properties of the foam mixture and / or the solid foam.

[0025] In one embodiment, the apparatus includes at least one conveying device for conveying the foam mixture or the solid foam to a storage area.

[0026] In one embodiment, the pattern is a stripe, a plate, a predetermined structure, a complex structure or a combination thereof. In one embodiment, the foam pattern is a foam stripe including elongated rod-shaped bubbles. In one embodiment, the foam pattern is formed from parallel foam stripes. In one embodiment, the foam pattern is a foam plate including disk-shaped bubbles, for example, disk-shaped or penny-shaped bubbles. In one embodiment, the foam pattern is a foam shape such as a predetermined structure or a complex structure including bubbles having one or more predetermined shapes. Such shapes include bubbles having a 2D projection that is, for example, in the shape of an I, H, U, Z, hollow O or a combination thereof. In one embodiment, the foam pattern is an anisotropic solid foam.

[0027] In one embodiment, for example, when an oriented rod-shaped structure is formed by elongated bubbles, the compressive strength increases in one direction and decreases in the lateral direction.

[0028] In one embodiment, a desired product can be formed from one or more foam patterns. In one embodiment, the product is a bulk product, film, rod, plate, block, or a combination thereof. In one embodiment, the product is formed from foam strips by placing foam strips together. The product can be obtained by the method described above, and the method may include the method according to any of its embodiments. In one embodiment, a solid foam is obtained by the method, and the solid foam comprises a foam mixture formed from a suspension containing a coagulant and bubbles, the bubbles in the solid foam are contracted in the off-length direction to form molded bubbles, the foam mixture is sprayed to form a foam pattern, and the foam mixture of the foam pattern is solidified into a solid foam. In one embodiment, the product is an anisotropic solid product.

[0029] In one embodiment, a product, such as a superstructure product, can be formed from more foam patterns, from at least two foam patterns. In one embodiment, the product is a laminated, stratified or similar larger-scale structure that includes two or more foam patterns, where the foam patterns are combined to form the product. In one embodiment, the product includes at least two foam patterns arranged one above the other to form a layered structure, and each foam pattern is arranged in a desired direction one above the other in the structure. In one embodiment, the product is formed from foam stripes. In one embodiment, the product is formed by arranging the foam patterns one above the other such that each foam pattern is arranged at a desired angle to the others. In one embodiment, flat foam patterns are arranged one above the other. In one embodiment, the foam patterns are arranged one above the other such that a foam pattern having a first direction alternates in position in the structure with a foam pattern having a second direction. In one embodiment, a layer of the foam pattern is dried and another layer of the foam pattern is placed on top of the existing layer. In one embodiment, the product is a cube or other layered structure.

[0030] In one embodiment, the method is used in a continuous process, a roll-to-roll process, the packaging industry, the construction industry or a combination thereof. It should be understood that the above embodiments may be used in combination with each other. Multiple embodiments may be combined to form further embodiments of the invention.

[0031] The methods, apparatuses and products described above have many advantages compared to conventionally known methods, apparatuses and products. In a conventionally known process, the Cellufoam process aims to produce a) a hydrophobic and b) a rigid foam structure by manipulating a bubble film structure. In the present invention, the geometric shape of the bubbles can be modified.

[0032] In one embodiment, this method is based on 1) modifying the rheological properties of a foam film by lowering the surface tension and increasing the viscosity by adding a chemical substance, such as methylcellulose or carboxymethylcellulose (CMC), and 2) placing the foam in stripes. Point 1) allows for increased drying time at high temperatures without loss of foam shape. Point 2) exposes the foam to tension due to its elongated shape, which causes foam contraction in the off-length direction. The method can produce anisotropic foam strips that can be placed together to form more complex structures in a continuous process.

[0033] Unlike conventional solutions, this method can be configured as a roll-to-roll process to produce large quantities of anisotropic foam and enable its use in applications with high foam demand, such as the packaging and construction industries. The process requires a thorough understanding of colloidal and foam rheology and is therefore highly non-trivial.

[0034] The present invention enables the production of different forms, such as anisotropic forms, in a continuous, expandable roll-to-roll process without such complexity. For example, a continuous process is not achievable by freeze casting. In the present invention, a specially prepared bio-based solid foam can be manufactured.

[0035] The accompanying drawings, included to provide a further understanding of the invention and to constitute part of this specification, illustrate several embodiments of the invention and, together with the description, help to illustrate the principles of the invention. [Brief explanation of the drawing]

[0036] [Figure 1]The measured elongation of bubbles is shown for eight different samples, indicating that the dimension in the elongation direction (y-axis) is eight times the elongation in the lateral direction (z-axis). [Figure 2] The fiber structure in the wall is oriented, resulting in high strength in the orientation direction and exhibiting elongation in the cell wall. [Figure 3] The orientation-dependent structure produced by the process exhibits significantly greater compressive strength along the bubbles and fibers (left) than in the lateral direction (right). [Figure 4] Modifying the process changes how bubbles interact with each other, leading to dramatic differences in stress-strain response. Figures a) and b) show four different groups of materials with different orientations and manufacturing processes. [Figure 5] This shows a comparison of FoamWood's strength per unit density against other materials, demonstrating that while its lateral strength (square) is lower than average foam, its strength in the cell elongation direction is exceptionally good for bio-based materials (circle). [Figure 6] A single extrusion process is shown, including schematic diagram a) and photograph b), in which drying of the rod under tension at a temperature higher than the viscosity transition of methylcellulose clogs / traps air bubbles and, consequently, the fibrous structure into an oriented state. [Figure 7] Examples of bulk products, rods, plates, and blocks are shown. [Figure 8] This diagram shows a series of parallel extrusion schematics in which one (or more) foam generators produce plate-like objects in a continuous process. [Modes for carrying out the invention]

[0037] The detailed description provided below in relation to the attached drawings is intended as an example and is not intended to represent the only form in which the example may be constructed or utilized. However, the same or equivalent functions and structures may be achieved by different examples.

[0038] Figure 1 shows measurements of anisotropic cells in eight different samples. The dimensions in the elongation direction (y-axis) are eight times greater than the dimensions in the transverse direction (z-axis). The elongation leads to an oriented fibrous structure in the cell walls, as shown in the high-magnification image in Figure 2. Small-scale structures in the cell walls can be inherited into larger structures, as shown in Figure 3. Figure 4 shows that the stress-strain (load-displacement) curves are clearly different depending on the orientation, which is evident in compression tests with accompanying practical gains. For example, at a strain of 0.1, the difference in load-bearing capacity is approximately 100 times along the elongation axis of the cell compared to the transverse direction. Figure 5 shows how the strength / density of FoamWood compares to other materials.

[0039] In the process, a homogeneous suspension containing solid fiber components is prepared and mixed with a sufficient amount of methylcellulose (MC). The suspension is then pumped into capillaries, where a joint is used to mix the air bubbles in the suspension and form a foam. The foam is placed on a moving surface, such as a wire surface, a solid surface, and / or a homogeneous surface, using a set of capillary nozzles that produce a set of foam stripes on the moving surface. These stripes of foam pass under an infrared heater, which increases the temperature, increases the evaporation rate, and produces the MC effect as described below.

[0040] MC acts as a surfactant in suspensions, 1) reducing the surface energy of the suspension and causing it to foam, and 2) increasing the viscosity of the suspension and extending the bubble shape relaxation time. The rheological behavior of MC is unique in that MC particles tend to expand in relation to temperature. This leads to a situation where the foam effectively traps and solidifies its structure when the foam's temperature is increased during drying.

[0041] The drying of liquid foam always leads to shrinkage due to a decrease in the amount of material (water) in the structure. When the foam is placed on wire in strips, shrinkage can be utilized, which creates additional stress towards the bubbles in the off-length direction, because shrinkage is impossible in the length direction. This, in turn, increases the anisotropy of the bubbles.

[0042] Figure 6 shows a schematic diagram of the apparatus in small-scale manufacturing. The foam is driven from the former onto a hot moving plate via controlled pneumatic pressure. As the foam is extruded, the linearly moving plate moves, forming a solid rod-shaped object, which is dried by a radiant heater. The process can be repeated until the desired number of rods are placed adjacent to each other on the moving plate. The rods are dried using the radiant heater. Furthermore, once the layer of rods is completely dry, another layer can be formed on top of the existing layer.

[0043] The process produces rod- and plate-like objects that can be stacked on the blocks shown in Figure 7. Figure 8 shows a large-scale machine that can continuously produce foam using multiple extruders.

[0044] A former is a device for forming foam with user-specific bubble radius and polydispersity. The average bubble radius is 10 μm to 100 mm, and polydispersity is 0.01 percent to 100 percent or the bubble radius. Polydispersity is the standard deviation of the bubble radius. Foam production is continuous because the raw material is continuously injected by pressure, for example, by air, liquid, or by a screw pump or similar method. The output is continuously injected into the extruder by a screw pump or similar device. The output can be other devices, for example, for quality control or storage units. The former can be rheomodified by ultrasound or sound waves, heated, cooled or vibrated to influence the flow of the raw material or foam.

[0045] An extruder is a device that disperses bubbles onto a moving surface and / or conveying device, ejecting the foam from a former. Dispersion generates internal shear, which stretches the bubbles and creates a pattern for generating internal structure in the foam. The pattern can be flat, rod-shaped, ridge-shaped, zigzag, on-off, dot-shaped, dash-shaped, corrugated, or a combination or similar. The number of extruders can be one or more in parallel operation. The number of extruders or sets of parallel extruders can operate in series. For example, extruders can operate in the following cases: independently with different patterns from other patterns, synchronously with the same patterns as other patterns, zero or more extruders operating independently with the same or different patterns, and / or zero or more extruders operating synchronously. Synchronization means both temporal and spatial synchronization, for example, different phases (start times) of dot patterns or different patterns or different starting positions of patterns. Extruders may incorporate rheologically modified vibrations, such as ultrasonic or sonic waves, to influence the flow of raw material or foam. Zero to multiple extruders can move to form patterns. Zero to multiple extruders can remain stationary to form patterns.

[0046] Coagulation devices, such as solidification apparatuses, are devices that change the rheological properties of a foam from a liquid state to a solid state. The solid state can be a gel, solid, or very viscous state with a viscosity exceeding 100 Pa·s (Pascal-seconds). Coagulation methods can be heating (0 to 5000°C), low temperature (-273 to 0°C), light including lasers, LEDs, heat, gas discharge, ultrasound, sound waves, magnetism, charging (e.g., removing charge screening by salt), chemical and / or pressure, or similar. The coagulation method is material-dependent and is a material-dependent parameter. For example, methylcellulose coagulates with heat. Methylcellulose coagulates at high temperatures of 30°C to 80°C depending on the degree of substitution. Heat can be infrared (radiant heat), conduction, or convection via a carrier gas. Water coagulates at low temperatures below 0°C. Alcohols coagulate at low temperatures below -4°C. Photopolymers coagulate with UV light. Shear thickening materials, such as corn starch, coagulate with sound waves and ultrasonic vibrations. Shear-thickening materials solidify when sound waves or ultrasonic vibrations cease. Iron powder solidifies in a magnetic field. Sand or granular materials solidify under pressure or load. Charged particles solidify when charge screening is removed; for example, charged stabilized cellulose solidifies when salt is added. Chemical solidification can be achieved by crosslinking, for example, by mixing two components similar to epoxy resin.

[0047] A conveying device is a device or operator, such as a human or robot, that can transport the form from the extruder to the storage area. Examples of conveying devices include conveyor belts and moving plates.

[0048] Rheomoderers, such as rheomodifying devices, are devices that alter the rheological (load-displacement) properties of a material and / or foam during manufacturing. Modification uses the same methods as solidification devices, but takes place during the process from material injection to foam storage. Solidification devices can also act as rheomodifiers.

[0049] The methods and apparatus are suitable in different embodiments for use in different industrial processes. The methods and apparatus are suitable in different embodiments for effectively producing different foam products from different raw materials.

[0050] The invention is not limited to the embodiments and examples described above. Rather, many modifications are possible within the scope of the inventive concept defined by the claims.

Claims

1. A method for continuously manufacturing solid foam, A step of forming a homogeneous suspension from a bio-based raw material containing fibers, wherein the suspension contains a coagulant, A step of adding a chemical substance to the suspension that reduces surface tension and increases viscosity, wherein the chemical substance is selected from methylcellulose, a derivative of methylcellulose, carboxymethylcellulose, hydroxypropylcellulose, ethylcellulose, or a combination thereof. The steps include forming a foam mixture containing air bubbles by mixing air bubbles into the suspension, The steps include: processing the foam mixture with an extruder, injecting the foam mixture from the extruder onto a moving surface through at least one nozzle to form a foam pattern including foam stripes for forming a plurality of rod-shaped structures parallel to each other, placing the foam pattern onto the moving surface, and using heat to solidify the foam mixture of the foam pattern to form an anisotropic solid foam containing bubbles such that the bubbles in the foam mixture contract in a direction perpendicular to the length direction of the foam stripes to form bubbles in the solid foam that extend in the length direction of the foam stripes; Includes, A method wherein shear is generated by spraying from the extruder onto the moving surface, the foam mixture is sprayed through at least one nozzle to form the foam pattern, and contraction and deformation of the foam mixture and the bubbles occur between the nozzle and the moving surface during the spraying and / or solidification and / or drying of the foam mixture.

2. The method according to claim 1, characterized in that the chemical substance is a photopolymer.

3. The method according to claim 1 or 2, characterized in that a solid fiber material is added to the bio-based raw material and / or the suspension, and the solid fiber material is selected from the group consisting of carbon fibers, carbon nanotubes, graphene, carbon mesh, hemp fibers, yarn and combinations thereof.

4. The method according to any one of claims 1 to 3, characterized in that the bio-based raw material is selected from the group consisting of biomass, wood, cellulose, or a combination thereof.

5. The method according to any one of claims 1 to 4, characterized in that the foam mixture is solidified by photocatalysis, crosslinking, freezing, or a combination thereof, in addition to heat.

6. The method according to any one of claims 1 to 5, characterized in that the foam mixture is solidified at a temperature of 30 to 90°C.

7. Apparatus for continuously manufacturing solid foam, A mixer for forming a homogeneous suspension from a bio-based raw material containing fibers, wherein the suspension contains a coagulant, An addition device for adding a chemical substance that reduces surface tension and increases viscosity, wherein the chemical substance is selected from methylcellulose, a derivative of methylcellulose, carboxymethylcellulose, hydroxypropylcellulose, ethylcellulose, or a combination thereof. A former for forming a foam mixture containing bubbles by mixing bubbles into the suspension, The present invention comprises at least one extruder for processing the foam mixture, at least one nozzle for spraying the foam mixture from the extruder onto a moving surface to form a foam pattern including foam stripes for forming a plurality of parallel rod-shaped structures, the moving surface on which the foam pattern is placed, and at least one solidification apparatus for forming an anisotropic solid foam containing bubbles, the foam mixture of the foam pattern being solidified by heat, such that the bubbles in the foam mixture contract in a direction perpendicular to the length direction of the foam stripes to form bubbles in the solid foam that extend in the length direction of the foam stripes. Equipped with, Shear is generated by the injection from the extruder onto the moving surface, the foam mixture is injected through at least one nozzle to form the foam pattern, and the shrinkage and deformation of the foam mixture and the bubbles occur between the nozzle and the moving surface during the injection and / or solidification and / or drying of the foam mixture. A device characterized by the following.

8. The apparatus according to claim 7, characterized in that the solidification apparatus includes at least one heater for solidifying the foam mixture by heat such that radiant heat, conductive heat and / or convective heat are used.

9. The apparatus according to claim 7 or 8, characterized in that the solidification apparatus acts as at least one rheomodifier for changing rheological properties.

10. The apparatus according to any one of claims 7 to 9, characterized in that the apparatus includes at least one conveying device for conveying the foam mixture or the solid foam to a storage area.

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