Method and apparatus for producing a solid foam, product and use

Abstract

The present application relates to a method and apparatus for continuous production of a solid foam. A homogeneous suspension is formed from a raw material, wherein the suspension comprises a curing agent, and a foam mixture comprising bubbles is formed by mixing the bubbles into the suspension. The foam mixture is injected via at least one nozzle to form a foam pattern, and the foam pattern is laid on a moving surface, and the foam mixture of the foam pattern is cured so as to form a solid foam, such that the bubbles of the foam mixture shrink in a non-length direction to form shaped bubbles. Furthermore, the present application relates to a product, and use of the method.

Description

Technical Field

[0001] This application relates to a method for the continuous production of solid foam and equipment for the continuous production of solid foam. Furthermore, this application relates to the use of solid foam products and the method for the continuous production of solid foam. Solid foam, such as bio-based solid foam, can be produced, and products can be manufactured from solid foam. Background Technology

[0002] The production of bio-based solid foams via liquid foaming is a promising method for obtaining novel lightweight materials. Currently, due to the slow drying process at high temperatures, foams produced using this method tend to have an isotropic structure, which also results in a relaxed bubble shape. In many applications, lightweight materials with wood-like properties, exhibiting high strength in one direction and good thermal conductivity in another, would be advantageous. Specifically, such anisotropic structures offer superior thermal insulation compared to isotropic structures.

[0003] One method for producing anisotropic foams is cryogenic casting, as illustrated in, for example, Lavaughn, N. & Bergstrom, L. (2017), *Nanocellulose-based foams and aerogels: processing, properties, and applications*, *Journal of Materials Chemistry A*, 5 (31), 16105-16117, where the foam is first forced into an elongated shape under high pressure and then frozen using a cryogenic gas. Upon freezing, the pressure decreases, causing water to precipitate from the foam while maintaining its structural integrity. This method is quite expensive due to the machinery required for high pressure and the energy consumption of freezing.

[0004] A porous material composed of cellulose fibers and gluten is known from WO2020011587A1. This application describes a method for producing rigid, biodegradable, isotropic foams with a hydrophobic structure.

[0005] A method for forming fibrous products is known from WO2015036659A1. A continuous roll-to-roll process produces thin or large paper-like sheets. Here, fiber formation is concentrated in non-scaled die casting and a continuous process. Furthermore, the foam is claimed to be an isotropic mixture, not anisotropic or elongated. Therefore, the foam does not exhibit significant orientation-dependent strength differences.

[0006] An insulation panel is known from US 10,357,936. In the insulation panel, a protective covering layer and an insulation layer are bonded together.

[0007] Furthermore, improvements to particulate-stabilized fluid-fluid interfaces are known from US20110111998A1; a tubular film manufacturing apparatus is known from JP5254982B2; a silver nanowire conductive ink for screen printing and its preparation method are known from CN201810602082A; a composition comprising an internal phase dispersed in a hydrophilic continuous phase is known from US 9789456B2; a differential expansion absorption structure is known from US7799967B2; a flame-retardant wood-plastic composite material is known from US 979034B2; a method for generating honeycomb cavities in thermoplastic materials is known from US4104207A, wherein the bubble-forming medium is bound to a carrier; a shaped nanoporous body is known from US20190022623A1; and a base material, its production method, and its uses are known from EP2114645B1. Summary of the Invention

[0008] The characteristics of the methods, equipment, products and uses are as given below.

[0009] In a method and apparatus for continuous production of solid foam, a suspension is formed from raw materials, a foam mixture is formed from the suspension, and the foam mixture is injected and solidified to produce solid foam.

[0010] A method for continuous production of solid foam may include the following steps: forming a homogeneous suspension from raw materials, wherein the suspension includes a curing agent; forming a foam mixture comprising bubbles by mixing air bubbles into the suspension; and injecting the foam mixture via at least one nozzle, such as through at least one nozzle, to form a foam pattern, laying the foam pattern on a moving surface, and curing the foam mixture of the foam pattern to form a solid foam, such that the bubbles of the foam mixture shrink and deform in the off-length direction to form a shaped bubble. The shrinkage and deformation processes of the foam mixture and the bubbles may occur during injection of the foam mixture, between the nozzle and the moving surface, and / or in combination with the nozzle during curing. In one embodiment, anisotropic solid foam is formed.

[0011] Anisotropy can be used to enhance the excellent thermal insulation and mechanical properties of solid foam materials. Anisotropic solid foams are difficult to prepare because fundamental foam physics causes the bubble shape to relax to an isotropic shape immediately upon removal of external stress. In wet bio-based foam manufacturing, 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 application includes a method for producing anisotropic foam using a continuous roll-to-roll process, which allows for scalability to large-scale production.

[0012] An apparatus for the continuous production of solid foam may include: at least one mixer for forming a homogeneous suspension from raw materials, wherein the suspension includes a curing agent; at least one foam generator for forming a foam mixture comprising bubbles by mixing air bubbles into the suspension; at least one nozzle for injecting the foam mixture to form a foam pattern, a movable surface on which the foam pattern is laid; and at least one curing device for curing the foam mixture of the foam pattern to form solid foam, such that the bubbles of the foam mixture shrink and deform in a non-length direction to form shaped bubbles. The shrinkage and deformation processes of the foam mixture and bubbles may occur in the nozzle during the injection of the foam mixture, between the nozzle and the movable surface, and / or during curing.

[0013] In one embodiment, the bubbles in the foam mixture may contract in a non-length direction to form elongated bubbles, such as elongated rod-shaped bubbles. In another embodiment, the bubbles in the foam mixture may contract in a non-length direction to form disc-shaped bubbles, such as disc-shaped or coin-shaped bubbles. Bubble formation may be performed during the injection of the foam mixture, between the nozzle and the moving surface, during curing, during drying, or a combination thereof, in conjunction with the nozzle. In one embodiment, the injection of the foam mixture via the nozzle and the laying of the foam mixture on the moving surface have an impact on bubble formation.

[0014] In the method and apparatus, any suitable raw material can be used. 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 residual materials, 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 curing agent. In one embodiment, the curing agent is added to the raw material and / or suspension. In one embodiment, the curing agent includes plastics, metals, and / or other components having a melting point. In one embodiment, the raw material includes fibers. In one embodiment, solid fibrous material is added to the raw material and / or suspension. In one embodiment, chemicals are added to the suspension as curing agents. In one embodiment, chemicals that reduce surface tension, increase viscosity, and facilitate curing are added to the suspension. In one embodiment, a solvent, such as water or xylene, is added to form the suspension.

[0015] In one embodiment, the device includes at least one adding means for adding chemical solid fibrous material and / or solvent to a suspension.

[0016] 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, methylcellulose derivatives, carboxymethylcellulose (CMC), hydroxypropylcellulose, ethylcellulose, etc., or a combination thereof. In one embodiment, the chemical is methylcellulose, methylcellulose derivatives, nanocellulose, microcellulose, or a combination thereof. In one embodiment, the chemical is carboxymethylcellulose (CMC). In one embodiment, the chemical is a photopolymer. The selected chemical is used as a curing agent, and the chemical can also be used as a rheology modifier, surfactant, and / or fibrous material. In one embodiment, a surfactant is added to the suspension.

[0017] In one embodiment, the fibers in the raw material or suspension include carbon fibers, carbon nanotubes, graphene, carbon mesh, lithium saponite, hemp, expanded polystyrene, polystyrene, polymers, polymer rods, 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, lithium saponite, hemp, expanded polystyrene, polystyrene, polymers, polymer rods, yarns, and combinations thereof. When the suspension includes fibers, the fibers of the raw material and / or solid fibrous material can be oriented according to the formed bubbles, such as elongated bubbles.

[0018] In one embodiment, the device includes one or more nozzles, such as at least two nozzles. In one embodiment, the foam mixture is injected via the nozzles to form a foam pattern.

[0019] In one embodiment, the foam mixture is processed by an extruder, and the foam mixture is injected from the extruder into a moving surface. In another embodiment, the foam mixture is formed in the extruder. In yet another embodiment, the apparatus includes at least one extruder comprising at least one nozzle.

[0020] Foam patterns can be formed by lay-up. In this document, lay-up means any lay-up, injection molding, extrusion, or a combination thereof. In one embodiment, the pattern is formed by extrusion. For example, during extrusion, shear forces can be generated to form the bubble.

[0021] The moving surface can be any moving device, such as a moving plate, conveyor belt, belt, or a combination thereof. In one embodiment, the moving surface moves linearly. In another embodiment, the moving surface moves at a speed from 0.1 mm / s to 50 m / s.

[0022] In one embodiment, the foam mixture is cured by heating, photocatalysis, crosslinking, freezing, or a combination thereof. In another embodiment, the foam mixture is cured by heating, thereby utilizing radiant heat, conductive heat, and / or convective heat during curing. The foam mixture may be dried during, before, or after curing.

[0023] In one embodiment, the curing apparatus includes at least one heater for curing the foam mixture by heating, thereby utilizing radiant heat, conductive heat, and / or convective heat. In one embodiment, the apparatus includes at least one radiant heater as the heater. In one embodiment, the apparatus includes at least one oven as the heater. In one embodiment, the apparatus includes at least one heated movable plate as the heater. In one embodiment, the movable plate is a heating plate, and curing is carried out by the heating plate and the radiant heater.

[0024] In one embodiment, the foam mixture is cured at a temperature of 1°C to 90°C. In another embodiment, the foam mixture is cured at a temperature of 30°C to 90°C.

[0025] In one embodiment, the device includes at least one rheology modifier for altering the rheological properties of foam mixtures and / or solid foams.

[0026] In one embodiment, the device includes at least one transport device for transporting foam mixtures or solid foams to a storage area.

[0027] In one embodiment, the pattern is a strip, a plate, a predetermined structure, a complex structure, or a combination thereof. In one embodiment, the foam pattern is a foam strip comprising elongated rod-shaped bubbles. In one embodiment, the foam pattern is formed from parallel foam strips. In one embodiment, the foam pattern is a foam board comprising disc-shaped bubbles, such as disc-shaped or coin-shaped bubbles. In one embodiment, the foam pattern is a foam shape, such as a predetermined structure or complex structure, comprising bubbles having a predetermined shape or a predetermined number of shapes. Such shapes include, for example, bubbles having a two-dimensional projection of an I-shape, H-shape, U-shape, Z-shape, hollow O-shape, or a combination thereof. In one embodiment, the foam pattern is an anisotropic solid foam.

[0028] In one embodiment, when an oriented rod-like structure is generated, for example, by elongated bubbles, the compressive strength increases in one direction and decreases in the transverse direction.

[0029] In one embodiment, the desired product may be formed from one or more foam patterns. In one embodiment, the product is a bulk product, film, rod, sheet, block, or a combination thereof. In one embodiment, the product is formed from foam strips by laying foam strips together. The product can be obtained by the methods described above, and the methods may include those according to any of the embodiments thereof. In one embodiment, solid foam is obtained by the method, and the solid foam comprises a foam mixture formed from a suspension comprising a curing agent and bubbles, and the bubbles in the solid foam have contracted in a non-length direction to form shaped bubbles, and the foam mixture has been injected to form a foam pattern, and the foam mixture of the foam pattern has been cured into solid foam. In one embodiment, the product is an anisotropic solid product.

[0030] In one embodiment, the product, such as a superstructure product, may be formed from more foam patterns, specifically from at least two foam patterns. In one embodiment, the product is a laminated, layered, or similar larger-scale structure comprising more than one foam pattern, and in which the foam patterns are combined to form the product. In one embodiment, the product comprises at least two foam patterns, one foam pattern disposed on top of another foam pattern to form a layered structure, and each foam pattern disposed on top of another foam pattern in a desired orientation within the structure. In one embodiment, the product is formed from foam strips. In one embodiment, the product is formed by disposing of foam patterns one on top of another, such that each foam pattern is disposed at a desired angle to each other. In one embodiment, a flat foam pattern is disposed one on top of another. In one embodiment, foam patterns are arranged one on top of another, such that foam patterns having a first orientation alternate with foam patterns having a second orientation within the structure. In one embodiment, a layer of foam pattern is dried, and another layer of foam pattern is disposed on top of an existing layer. In one embodiment, the product is a cube or other layered structure.

[0031] In one embodiment, the method is used in continuous processes, roll-to-roll processes, the packaging industry, the construction industry, or combinations thereof.

[0032] It should be understood that the above embodiments can be used in any combination with each other. Several embodiments in the embodiments can be combined together to form other embodiments of the present invention.

[0033] Compared with previously known methods, apparatus and products, the above-described methods, apparatus and products have many advantages.

[0034] In previously known processes, the Cellufoam process aims to generate a) hydrophobic foams and b) rigid foam structures by manipulating the bubble film structure. In this invention, the geometry of the bubble can be altered.

[0035] In one embodiment, this method is based on 1) altering the rheological properties of the foam film by reducing its surface tension and increasing its viscosity by adding chemicals such as methylcellulose or carboxymethylcellulose (CMC), and 2) laying the foam into strips. Point 1) allows for increased drying time at high temperatures without losing the foam shape. Point 2) causes the foam to experience tension due to its elongated shape, resulting in shrinkage in the non-length direction. This method can produce anisotropic foam strips that can be laid together in a continuous process to form more complex structures.

[0036] Unlike previous solutions, this approach allows for the development of roll-to-roll processes for producing large quantities of anisotropic foams, enabling their use in applications with high foaming requirements, such as the encapsulation and construction industries. This process demands a deep understanding and integration of colloid and foam rheology, making it crucial.

[0037] This invention enables the production of various types of foam, such as anisotropic foam, without the complexities of continuous, scalable roll-to-roll processes. For example, continuous processes are not feasible through cryogenic casting.

[0038] In this invention, specially customized bio-based solid foams can be manufactured. Attached Figure Description

[0039] The accompanying drawings are included to provide a further understanding of the invention and form part of this specification. The drawings illustrate some embodiments of the invention and, together with the description, help to explain the principles of the invention. In the drawings:

[0040] Figure 1 The measured elongation of the bubble is shown, indicating that for eight different samples, the dimension in the elongation direction (y-axis) is eight times the elongation in the transverse direction (z-axis).

[0041] Figure 2 The elongation of the bubble wall is shown, which leads to the orientation of the fiber structure within the wall, resulting in high strength in the oriented direction.

[0042] Figure 3 A structure is shown in which the orientation-related structure has been produced by a process in which the compressive strength along the bubble and fiber (left) is significantly greater than the compressive strength in the transverse direction (right).

[0043] Figure 4 The modified process alters the way bubbles interact, leading to significant differences in stress-strain response. Figures a) and b) show four different groups of materials with different orientations and manufacturing processes.

[0044] Figure 5 The diagram shows a comparison of the unit density strength of foamwood with other materials, demonstrating that although its transverse strength (square) is lower than that of average foam, its strength in the elongated direction (circular) is excellent for a bio-based material.

[0045] Figure 6 A single extrusion process is shown, including schematic view a) and photographic view b), in which the dry bar is blocked / prevented under tension at a temperature above the viscosity transition of methylcellulose, and (thereby) the fiber structure enters an oriented state.

[0046] Figure 7Examples of bulk products, bars, plates, and blocks are shown, as well as

[0047] Figure 8 A schematic diagram is shown of multiple parallel extruders with one (or more) foam generators producing sheet-like objects in a continuous process. Detailed Implementation

[0048] The detailed description provided below, in conjunction with the accompanying drawings, is intended as a description of examples and not as representing the only form in which examples can be constructed or utilized. However, the same or equivalent functionality and structure can be implemented through different examples.

[0049] Figure 1 Measurements of anisotropic bubbles in eight different samples are shown. The dimension in the elongation direction (y-axis) is eight times the dimension in the transverse direction (z-axis). Elongation results in a directional fiber structure in the bubble wall, such as... Figure 2 The image is shown at high magnification. Small-scale structures in the bubble wall can be inherited by large-scale structures, such as... Figure 3 As shown. Figure 4 The actual gain is revealed in the accompanying compression test, as the stress-strain (load-displacement) curves differ significantly depending on orientation. For example, at a strain of 0.1, the load-bearing capacity along the long axis of the bubble differs by nearly 100 times compared to the transverse direction. Figure 5 The strength / density of foamwood is shown compared to other materials.

[0050] In this 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 a capillary tube, where a connector is used to mix the gas bubbles in the suspension to form foam. A set of foam strips is generated on a moving surface using a set of capillary nozzles, laying the foam on the moving surface, such as a wire surface, a solid surface, and / or a flat surface. These foam strips pass under an infrared heater, which increases the temperature, increases the evaporation rate, and causes the MC effect, as explained below.

[0051] MC acts as a surfactant that 1) reduces the surface energy of a suspension to induce foaming, and 2) increases the viscosity of the suspension, thereby increasing the foam shape relaxation time. Furthermore, the rheological behavior of MC is unique in a sense, as MC particles tend to expand with temperature. This leads to a situation where the foam effectively stalls as the temperature rises during drying, resulting in structural solidification and stagnation.

[0052] The drying of liquid foam always leads to its shrinkage due to the reduction in the amount of material (water) in the structure. When the foam is laid in strips on a wire, the shrinkage can be used to generate additional stress on the foam in the non-length direction, since shrinkage is impossible in the length direction. This, in turn, increases the anisotropy of the foam.

[0053] Figure 6 A schematic diagram of the apparatus in small-scale production is shown. Foam is driven from a foam generator onto a heated moving plate by controlled air pressure. As the foam is extruded, the linear moving plate moves, producing solid rod-shaped objects, which are dried by a radiant heater. This process can be repeated until the desired amount of rods is deposited one after another on the moving plate. The rods are dried using a radiant heater. Furthermore, once the rod layer is completely dry, another layer can be formed on top of the existing layer.

[0054] This process produces rod-shaped and plate-shaped objects, which can be laminated into… Figure 7 The block shown. Figure 8 This demonstrates a large machine capable of continuously producing foam using multiple extruders.

[0055] A foam generator is a device used to produce foam with user-specific bubble radii and polydispersity; the average bubble radius is from 10 micrometers to 100 millimeters, and the polydispersity is from 0.01% to 100% of the bubble radius. Polydispersity is the standard deviation of the bubble radius. Foam production is continuous because the raw material is continuously injected under pressure, such as by air, liquid, or a screw pump, or similar methods. The output is continuously injected into an extruder using a screw pump or similar device. The output may be used for other devices, such as quality control or storage units. Foam generators can be rheologically modified using ultrasound or sound waves by heating, cooling, or agitation to influence the flow of the raw material or foam.

[0056] An extruder is a device that disperses foam onto a moving surface and / or a transport device and injects foam from a foam generator. The dispersion generates internal shear that elongates the foam and creates a pattern for producing the internal structure of the foam. Patterns can be flat, rod-shaped, ridged, serrated, "on-off," dotted, dashed, wavy, or a combination thereof. The number of extruders can be one or more operating in parallel. Multiple extruders or a group of parallel extruders can operate in series. For example, extruders can operate independently with patterns different from those of other extruders, synchronously with other patterns, with zero or more extruders operating independently with the same or different patterns, and / or with zero or more extruders operating synchronously. Synchronization means temporal and spatial synchronization, such as different phases (start times) of dotted patterns, or different patterns, or different starting positions of patterns. Extruders may include rheologically modified shaking using ultrasound or sound waves to influence the flow of the feedstock or foam. Zero or more extruders can move to create patterns. Zero or more extruders can remain stationary to create patterns.

[0057] Curing agents, such as curing devices, are devices that change the rheological properties of foam from its liquid phase to its solid phase. The solid-like phase can be a gel or solid or a high-viscosity phase with a viscosity exceeding 100 Pa·s (Pascal-seconds). Curing methods can be thermal (0°C to 5000°C), cold (-273°C to 0°C), light (including lasers), LEDs, heat, gas discharge, ultrasound, sound waves, magnetism, charging (by removing charge shielding, for example, with salt), chemical and / or pressure, or similar. The curing method depends on the material and is a material-dependent parameter. For example, methylcellulose is cured by heat. Depending on the degree of substitution, methylcellulose is cured at high temperatures from 30°C to 80°C. The heat can be infrared (radiative heat), conductive heat, or convective heat through a carrier gas. Water cures at low temperatures below 0°C. Alcohol cures at low temperatures below -4°C. Photopolymers are cured under ultraviolet light. Shear-thickening materials, such as corn starch, are cured by acoustic and ultrasonic vibrations. Shear-thinned materials solidify when sound or ultrasonic vibrations cease. Iron powder solidifies in a magnetic field. Sand or granular materials solidify under pressure or load. Charged particles solidify when the charge shielding is removed; for example, charged stabilized cellulose solidifies when salt is added. Chemical curing can be achieved through cross-linking, for example, by mixing two components similar to an epoxy resin.

[0058] A transporter is a device or operator, such as a person or robot, that transports foam from an extruder to a storage area. Examples of transporters are conveyor belts, moving plates, or the like.

[0059] Rheology modifiers, such as rheology modifiers, are devices used during manufacturing to alter the rheological (load-displacement) properties of materials and / or foams. Modification uses the same methods as curing agents, but occurs during the process from material injection to foam storage. Curing agents can act as rheology modifiers.

[0060] The methods and apparatus, in different embodiments, are suitable for different industrial processes. The methods and apparatus, in different embodiments, are suitable for efficiently producing different foam products from different raw materials.

[0061] The present invention is not limited to the embodiments and examples mentioned above; rather, many variations are possible within the scope of the inventive concept defined by the claims.

Claims

1. A method for continuous production of solid foam, wherein a suspension is formed from raw materials, air is added to the suspension to form a foam mixture, and foam is formed from the foam mixture, characterized in that, The method includes - A homogeneous suspension is formed from bio-based raw materials containing fibers, wherein the suspension includes a curing agent. - Chemicals that reduce surface tension and increase viscosity are added to the suspension. These chemicals are selected from methylcellulose, methylcellulose derivatives, carboxymethylcellulose, hydroxypropylcellulose, ethylcellulose, or combinations thereof. - By mixing bubbles into the suspension, a foam mixture comprising bubbles is formed, and - The foam mixture is processed by an extruder and injected from the extruder through at least one nozzle into a moving surface to form a foam pattern comprising parallel foam strips to produce a rod-shaped structure, and the foam pattern is laid on the moving surface and the foam mixture of the foam pattern is cured by heating to form an anisotropic solid foam comprising bubbles, such that the bubbles of the foam mixture shrink in the non-length direction to form elongated bubbles in the foam.

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

3. The method according to claim 1, characterized in that, A solid fibrous material is added to the raw material and / or the suspension, and the solid fibrous material is selected from the group consisting of carbon fibers, carbon nanotubes, graphene, lithium saponite, hemp, polymers, and combinations thereof.

4. The method according to claim 3, characterized in that, The solid fiber material is polystyrene.

5. The method according to claim 1, characterized in that, A solid fiber material is added to the raw material and / or the suspension, and the solid fiber material is a carbon mesh.

6. The method according to claim 1, characterized in that, A solid fiber material is added to the raw material and / or the suspension, and the solid fiber material is yarn.

7. The method according to claim 1, characterized in that, The bio-based raw material is biomass.

8. The method according to claim 1, characterized in that, The bio-based raw material is selected from the group consisting of: treated bio-based materials, untreated bio-based materials, or combinations thereof.

9. The method according to claim 1, characterized in that, The bio-based raw material is a bio-based residual material.

10. The method according to claim 1, characterized in that, The bio-based raw materials are forest-based materials.

11. The method according to claim 1, characterized in that, The bio-based raw material is a wood-based material.

12. The method according to claim 1, characterized in that, The bio-based raw material is wood.

13. The method according to claim 1, characterized in that, The bio-based raw material is cellulose.

14. The method according to claim 1, characterized in that, The foam mixture is cured by heating, photocatalysis, cross-linking, freezing, or a combination thereof.

15. The method according to claim 1, characterized in that, The foam mixture is cured at a temperature of 1°C to 90°C.

16. The method according to any one of claims 1 to 15, characterized in that, The product is formed from one or more foam patterns.

17. An apparatus for continuous production of solid foam, the apparatus comprising at least one mixer for forming a suspension from raw materials, at least one foam generator for forming a foam mixture by adding air to the suspension, and means for forming foam from the foam mixture, characterized in that, - The mixer is used to form a homogeneous suspension from a bio-based raw material containing fibers, wherein the suspension includes a curing agent. - The device includes at least one adding device for adding a chemical that reduces surface tension and increases viscosity to the suspension, the chemical being selected from methylcellulose, methylcellulose derivatives, carboxymethylcellulose, hydroxypropylcellulose, ethylcellulose, or combinations thereof. - The foam generator is used to form a foam mixture comprising bubbles by mixing bubbles into the suspension, and - The apparatus includes at least one extruder and at least one nozzle for injecting the foam mixture from the extruder into a moving surface to form a foam pattern comprising parallel foam strips to produce a rod-shaped structure, wherein the moving surface moves linearly at a speed of 0.1 mm / s to 50 m / s and the moving surface is a moving plate, and the foam pattern is laid on the moving surface; and at least one curing device including at least one heater for curing the foam mixture of the foam pattern by heating to form an anisotropic solid foam comprising bubbles, such that the bubbles of the foam mixture shrink in a non-length direction to form elongated bubbles in the foam.

18. The device according to claim 17, characterized in that, The curing apparatus includes at least one heater for curing the foam mixture by heating, thereby using radiant heat, conductive heat and / or convective heat.

19. The device according to claim 17, characterized in that, The device includes at least one rheology modifier for altering rheological properties.

20. The device according to any one of claims 17 to 19, characterized in that, The equipment includes at least one transport device for transporting the foam mixture or the solid foam to a storage area.

21. A solid foam product obtained by the method according to any one of claims 1 to 16, characterized in that, The solid foam comprises a foam mixture formed from a suspension of a bio-based raw material containing fibers, a curing agent, and bubbles, and chemicals that reduce surface tension and increase viscosity, the chemicals being selected from methylcellulose, methylcellulose derivatives, carboxymethylcellulose, hydroxypropylcellulose, ethylcellulose, or combinations thereof, and the foam mixture has been injected to form a foam pattern comprising parallel foam strips to produce a rod-like structure, and the foam mixture of the foam pattern has been cured to form an anisotropic solid foam comprising bubbles, and the bubbles in the solid foam have contracted in a non-length direction to form shaped bubbles.

22. The product according to claim 21, characterized in that, The product comprises at least two foam patterns, one foam pattern being disposed on top of the other foam pattern to form a layered structure, and in the structure, each foam pattern being disposed on top of the other foam pattern in a desired orientation.

23. Use of the method according to any one of claims 1 to 16, characterized in that, The method is used for continuous processes.

24. Use of the method according to any one of claims 1 to 16, characterized in that, The method is used for roll-to-roll processes.

25. Use of the method according to any one of claims 1 to 16, characterized in that, The method is used in the packaging industry.

26. Use of the method according to any one of claims 1 to 16, characterized in that, The method is used in the construction industry.

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