Composite and method for producing composite

Abstract

To provide a composite having excellent mechanical strength and moisture resistance and having a good texture, and a method for producing the composite.SOLUTION: A composite comprises: mushroom hyphae; starch; a plasticizer; a crosslinking agent; and a fiber. The composite preferably comprises a starch composite particle in a form of a particle, and the starch and the plasticizer are contained in the starch composite particle. Further, the crosslinking agent is preferably contained in the starch composite particle. The starch composite particle preferably has an average particle diameter of 1 μm or more and 60 μm or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a composite and a method for producing the composite. [Background technology]

[0002] In recent years, the market has been demanding products made from naturally derived materials that have a low environmental impact. For example, Patent Document 1 discloses a composite that uses fibers, plasticizers, and starch to reduce the use of petroleum-derived materials. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-155655 Summary of the Invention [Problem to be solved by the invention]

[0004] However, starch plasticized with a plasticizer has high moisture absorption. Therefore, for example, when a composite is placed in a high-humidity environment, the plasticized starch softens and the mechanical strength of the composite may decrease. In addition, there is room for improvement in the texture of the composite, which limits the applications of the composite. Therefore, there is a need to realize a composite that has excellent mechanical strength and moisture resistance as well as good texture. [Means for solving the problem]

[0005] The composite according to the application example of the present invention is It comprises mushroom mycelium, starch, a plasticizer, a cross-linking agent, and fibers.

[0006] A method for producing a composite according to an application example of the present invention includes the steps of: A method for producing a composite according to an application example of the present invention, comprising the steps of: A step of defibrating mushroom mycelium to obtain said mycelium; mixing the mycelia, the starch, the plasticizer, the cross-linking agent, and the fibers to obtain the composite; It has.

[0007] A method for producing a composite according to an application example of the present invention includes the steps of: A method for producing a composite according to an application example of the present invention, comprising the steps of: forming a medium having the starch, the plasticizer, the cross-linking agent, and the fiber; inoculating the medium with an inoculum of the mycelium; Cultivating the seed culture to obtain the complex; It has. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a conceptual diagram of starch composite particles dispersed in hyphae and fibers. [Figure 2] 1A to 1C are process diagrams showing the configuration of a method for producing a composite according to an embodiment. [Figure 3] FIG. 1 is a diagram schematically illustrating an example of a composite manufacturing apparatus for manufacturing a composite according to an embodiment. [Figure 4] 10A to 10C are process diagrams showing the configuration of a modified example of the method for producing a composite according to the embodiment. [Figure 5] Table 1 shows the configuration of the composites of each Example and Comparative Example and the configuration of the starch composite particles used to produce the composites. [Figure 6] Table 2 shows the composition of the composites of each Example and Comparative Example and the composition of the starch composite particles used to produce the composites. [Figure 7] Table 3 shows the composition of the composites of each Example and Comparative Example and the composition of the starch composite particles used to produce the composites. [Figure 8] Table 4 shows the composition of the composites of each Example and Comparative Example and the composition of the starch composite particles used to produce the composites. [Figure 9] Table 5 shows the composition of the composites of each Example and Comparative Example and the composition of the starch composite particles used to produce the composites. [Figure 10]Table 6 shows the composition of the composites of each Example and Comparative Example and the composition of the starch composite particles used to produce the composites. [Figure 11] Table 7 shows the composition of the composites of each Example and Comparative Example and the composition of the starch composite particles used to produce the composites. DETAILED DESCRIPTION OF THE INVENTION

[0009] The composite and the method for producing the composite of the present invention will be described in detail below based on preferred embodiments shown in the accompanying drawings.

[0010] 1. Complex First, the composite according to the embodiment will be described.

[0011] The composite according to the embodiment comprises mushroom mycelia, starch, a plasticizer, a cross-linking agent, and fibers.

[0012] 1.1. Mushroom mycelium Mushroom mycelia are the fibrous structures that make up the mycelium of mushrooms. The type of mushroom is not particularly limited, but examples thereof include Agaricus arvensis, Agrocybe brasiliensis, Amylomyces rouxii, species of the genus Amylomyces, Armillaria mellea, Aspergillus nidulans, Aspergillus niger, Aspergillus oryzae, Ceriporia lacerata, Coprinus comatus, Fibroporia vaillantii, Fistulina hepatica, Flammulina velutipes, and the like. velutipes, Fomitopsis officinalis, Ganoderma sessile, Ganoderma tsugae, Hericium erinaceus, Hypholoma capnoides, Hypholoma sublaterium, Inonotus obliquus, Lactarius chrysorrheus, Macrolepiota procera, Morchella angusticeps, Myceliophthora thermophila, Neurospora crassa crassa, Penicillium camembertii, Penicillium chrysogenum, Penicillium rubens, Phycomyces brachestrianusblakesleeanus, Pleurotus djamor, Pleurotus ostreatus, Polyporus squamosus, Psathyrella aquatica, Rhizopus microspores, Rhizopus oryzae, Schizophyllum commune, Streptomyces venezuelae, Stropharia rugosoannulata, Thielavia terrestris, Ustilago maydis), shiitake mushrooms (Lentinula genus), tomboy mushrooms (Meripilus genus), maitake mushrooms (Grifola genus), giant ginkgo mushrooms (Leucopaxillus genus), polyporaceae (Fomitopsis genus), and matsutake mushrooms (Tricholoma genus).

[0013] The mushroom mycelia may be aggregated together to form a mycelium. In other words, some or all of the mycelia in the complex may be mycelia formed by aggregation of mycelia. In the following description, mushroom mycelia will also be simply referred to as "mycelium."

[0014] The average diameter of the hyphae is preferably set to be smaller than the average diameter of the fibers, which makes it easier to impart the smooth texture derived from the hyphae to the composite.

[0015] The average diameter of the hyphae is not particularly limited, but is preferably 0.1 μm to 10.0 μm, more preferably 0.3 μm to 5.0 μm. If the average diameter of the hyphae is within this range, the texture of the composite can be particularly improved.

[0016] The average diameter of the hyphae is measured as follows. First, the complex is enlarged and an image is taken so that at least 100 hyphae fit within a single image. Next, at least 10 hyphae are randomly selected and their widths are measured. The average of these measurements is then used as the average hypha diameter.

[0017] The average length of the hyphae is not particularly limited, but is preferably 0.001 mm to 3.0 mm, more preferably 0.010 mm to 2.0 mm, and even more preferably 0.050 mm to 1.0 mm. If the average length of the hyphae is within the above range, for example, when the composite is formed into a sheet, the hyphae will be oriented along the surface of the composite and will be moderately entangled with each other. This will particularly improve the texture of the composite.

[0018] The average length of the hyphae is measured as follows. First, the complex is enlarged and an image is taken so that at least 100 hyphae fit within a single image. Next, at least 10 hyphae are randomly selected and the maximum length possible within the hyphae image is measured. The average of these measurements is then used as the average hypha length.

[0019] The mycelia preferably contain chitin. Chitin is contained as a component of the cell wall that constitutes the mycelia. Chitin is a polymeric polysaccharide whose structural unit is N-acetylglucosamine, which is glucose with an acetamide group added. Since chitin has a hydroxyl group, the mycelia containing chitin are more likely to be crosslinked by a crosslinking agent.

[0020] 1.2.Starch Starch is a molecule formed by the polymerization of multiple α-glucose molecules via glycosidic bonds. Starch may be a linear molecule or may contain branches. Starch derived from, for example, various plants can be used. More specifically, starch derived from, for example, cereals such as corn, wheat, and rice; beans such as broad beans, mung beans, and adzuki beans; tubers such as potatoes, sweet potatoes, and tapioca; wild plants such as bracken and kudzu; and palms such as sago palm can be used.

[0021] The starch may be modified starch. Examples of modified starches include acetylated adipate cross-linked starch, acetylated starch, oxidized starch, sodium octenyl succinate starch, hydroxypropyl starch, hydroxypropylated phosphate cross-linked starch, phosphated starch, phosphate-esterified phosphate cross-linked starch, urea phosphate-esterified starch, sodium starch glycolate, and high-amylose corn starch. The starch may also be modified starch. Examples of modified starches include those obtained by processing or modifying starch, and specific examples include dextrin.

[0022] The weight-average molecular weight of the starch is not particularly limited, but is preferably 50,000 to 400,000, more preferably 70,000 to 300,000, and even more preferably 80,000 to 280,000. A molecular weight within this range allows for better mixing of the starch and plasticizer. This facilitates plasticization by heating even in the absence of water or in the presence of only a small amount of water, resulting in superior strength and productivity of the composite.

[0023] The weight-average molecular weight of starch can be determined by gel permeation chromatography, using polystyrene as the standard.

[0024] The composite may have particulate starch composite particles. The starch composite particles contain at least starch and a plasticizer. By taking the form of starch composite particles, the starch and plasticizer can be distributed evenly. This makes the composite homogenous, and can improve the moisture resistance and mechanical strength of the composite. Note that there may be starch or plasticizer not contained in the starch composite particles.

[0025] The average particle size of the starch composite particles is not particularly limited, but is preferably 1 μm to 60 μm, more preferably 1 μm to 50 μm, even more preferably 2 μm to 30 μm, and particularly preferably 2 μm to 20 μm. When the average particle size of the starch composite particles is within the above range, the dispersion state of the starch composite particles between the hyphae and fibers in the composite is more likely to be more uniform, and a composite with better mechanical strength, moisture resistance, and texture can be obtained.

[0026] The average particle size of the starch composite particles is the particle size D50 at which the cumulative frequency from the small diameter side in the volumetric particle size distribution is 50%, as measured using a particle size distribution analyzer based on the laser diffraction scattering method, for example. Examples of particle size distribution analyzers include the Microtrac MT3000II manufactured by Nikkiso Co., Ltd.

[0027] 1.3. Plasticizers A plasticizer has the property of plasticizing starch. The plasticizer is preferably contained in starch composite particles and contributes to the plasticization of starch. When starch is plasticized by a plasticizer, the starch exhibits thermoplastic properties. In this specification, such plasticized starch may be referred to as "thermoplastic starch," "plasticized starch," etc.

[0028] Examples of the plasticizer include sugar alcohols. The plasticizer is preferably one or more selected from sugar alcohols. By selecting a plasticizer from sugar alcohols, the starch can be more easily plasticized. This makes it easier for the starch composite particles to bind together hyphae, fibers, and hyphae and fibers, thereby imparting better strength to the composite.

[0029] Sugar alcohols are a type of sugar produced by reducing the carbonyl group of aldoses or ketoses. Examples of sugar alcohols include maltitol, lactitol, tetritol, pentitol, hexitol, erythritol, sorbitol, xylitol, and mannitol. Among these, one or more selected from sorbitol, erythritol, and D-mannitol are more preferred.

[0030] Among sugar alcohols, sorbitol, erythritol, and D-mannitol can more easily plasticize starch and do not cause plasticization at room temperature, which facilitates handling during the manufacturing process and handling of the produced composite. This allows the starch composite particles to more easily bind together hyphae, fibers, and hyphae and fibers, thereby imparting better mechanical strength to the composite.

[0031] On the other hand, polyglycerin may be used as the plasticizer. Polyglycerin is a polymerized form of glycerol, and the degree of polymerization is not particularly limited. Furthermore, as the plasticizer, any compound containing many hydroxyl groups is considered to have the property of plasticizing starch, and such a compound may also be used.

[0032] The content of the plasticizer is preferably 0.05 to 0.90 in mass ratio, more preferably 0.10 to 0.85, and even more preferably 0.10 to 0.80, relative to the total content of starch and plasticizer. When the content of the plasticizer is within the above range, the starch is more sufficiently plasticized, and better mechanical strength can be imparted to the composite.

[0033] 1.4. Crosslinking Agents When heat is applied, the crosslinking agent reacts with the hydroxyl groups contained in the mycelia, starch, plasticizer, and fibers. This contributes to crosslinking these components, improving the mechanical strength and moisture resistance of the composite. In particular, the texture of the composite can be improved by crosslinking the mycelia with the crosslinking agent.

[0034] The cross-linking agent is an organic compound having two or more carboxyl groups, and is preferably contained in the starch composite particles to contribute to the good holding of the starch composite particles.

[0035] The crosslinking agent is not particularly limited as long as it is an organic compound having multiple carboxy groups. Examples of the crosslinking agent include aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid, aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid, dicarboxylic acids having hydroxyl groups such as tartaric acid and malic acid, tricarboxylic acids such as citric acid and aconitic acid, and amino acids having multiple carboxy groups such as aspartic acid and glutamic acid. One or a mixture of two or more of these may be used.

[0036] The crosslinking agent is preferably one or more dicarboxylic acids, primarily in terms of reactivity with hydroxyl groups. Dicarboxylic acids can form ester bonds with the hydroxyl groups of the mycelium, starch, plasticizer, and fiber, chemically crosslinking fiber-to-starch, fiber-to-fiber, starch-to-starch, mycelium-to-fiber, mycelium-to-starch, and mycelium-to-mycelium. In particular, when both starch and plasticizer are present, as in starch composite particles, the crosslinking agent crosslinks with the starch via the plasticizer. This improves the mechanical strength, moisture resistance, and texture of the composite. Ester bonds (chemical bonds) can be confirmed by FTIR.

[0037] The crosslinking agent is more preferably one or more dicarboxylic acids selected from succinic acid, adipic acid, and sebacic acid, which allows the aforementioned chemical crosslinks to be formed by ester bonds, thereby further improving the mechanical strength, moisture resistance, and texture of the composite.

[0038] The content of the crosslinking agent is preferably 0.01 to 0.60 in mass ratio, more preferably 0.01 to 0.50, even more preferably 0.05 to 0.20, and particularly preferably 0.10 to 0.20, relative to the total content of starch, plasticizer, and crosslinking agent. By having the content of the crosslinking agent within the above range, the degree of chemical crosslinking described above is improved, thereby making it possible to further improve the mechanical strength, moisture resistance, and texture of the composite.

[0039] 1.5. Preparation of Starch Composite Particles The starch composite particles are formed, for example, by a spray-drying method. The spray-drying method is not particularly limited, and any known method can be used. However, since the starch composite particles contain a plasticizer, it is preferable to spray-dry the starch composite particles while minimizing the application of heat.

[0040] In the spray-drying method, starch, a plasticizer, and a crosslinking agent are mixed in water, and heated as necessary to prepare a gelatinized solution. The heating temperature is preferably 100°C or lower, more preferably 98°C or lower, and even more preferably 95°C or lower. If the crosslinking agent has low water solubility when preparing the gelatinized solution, the starch and the plasticizer may be mixed in water, and heated as necessary to prepare a gelatinized solution. The crosslinking agent may then be dissolved in a suitable water-soluble organic solvent such as ethanol, and the resulting solution may be mixed with the gelatinized solution and subjected to spray drying.

[0041] When producing starch composite particles by the spray-drying method, the size and shape of the resulting starch composite particles can be adjusted by appropriately adjusting the supply rate of the mixed liquid (gelatinized liquid), the inlet temperature, the outlet temperature, the residence time, the atomizer rotation speed, the spray pressure, etc.

[0042] In the spray drying method, the temperature of the inlet through which the solution is introduced into the spray drying apparatus (inlet temperature) is preferably 100° C. or higher and 200° C. or lower, more preferably 110° C. or higher and 190° C. or lower, and even more preferably 120° C. or higher and 180° C. In the spray drying method, the temperature of the outlet through which the solution is sprayed and discharged (outlet temperature) is preferably 40° C. or higher and 100° C. or lower, more preferably 50° C. or higher and 90° C. or lower, and even more preferably 60° C. or higher and 80° C. or lower.

[0043] The spray dryer is not particularly limited, but for example, ADL311S-A manufactured by Yamato Scientific Co., Ltd. can be used.

[0044] Fiber The fibers are not particularly limited, and a wide variety of fiber materials can be used. Examples of fibers include natural fibers such as animal fibers and plant fibers, and chemical fibers such as organic fibers, inorganic fibers, and organic-inorganic composite fibers. Specifically, at least one selected from the group consisting of cellulose, silk, wool, cotton, hemp, kenaf, flax, ramie, jute, Manila hemp, sisal, coniferous trees, and broad-leaved trees is preferably used. These may be used alone or in appropriate mixtures, or may be used as regenerated fibers that have been purified, etc.

[0045] Examples of raw materials for the fibers include waste paper and old cloth, and the fibers may contain at least one of the above fibers. The fibers may also be subjected to various surface treatments. The fiber material may be a pure substance, or may contain multiple components such as impurities, additives, and other components.

[0046] Among these, fibers containing cellulose are more preferable. Cellulose contains many hydroxyl groups in its molecular structure. Therefore, it easily reacts with crosslinking agents, and it is easy to improve the mechanical strength and moisture resistance of the composite.

[0047] The average diameter of the fibers is not particularly limited, but is preferably thicker than the average diameter of the mycelia. Specifically, it is preferably 1.0 μm or more and 100.0 μm or less, and more preferably 3.0 μm or more and 50.0 μm or less. If the average diameter of the fibers is within this range, the mechanical strength of the composite can be particularly increased.

[0048] The average diameter of the fibers is measured as follows. First, the composite is magnified and an image is taken so that at least 100 fibers fit within one image. Next, at least 10 fiber images are randomly selected and the width of the fiber images is measured. The average of these measurements is then taken as the average fiber diameter.

[0049] The average length of the fibers is not particularly limited, but is preferably 0.001 mm to 5.0 mm, more preferably 0.002 mm to 3.0 mm, and even more preferably 0.003 mm to 2.0 mm. When the average fiber length is within this range, the fibers are oriented along the surface of the composite, for example, and the fibers are moderately entangled with each other. This can particularly increase the mechanical strength of the composite.

[0050] The average fiber length is measured as follows. First, the composite is magnified and an image is taken so that at least 100 fibers fit within one image. Next, at least 10 fiber images are randomly selected, and the maximum length possible within the fiber image is measured. The average of the measurements is then taken as the average fiber length.

[0051] 1.7. Composite Forming The composite is formed, for example, by mixing mycelia, starch, plasticizer, crosslinker, and fiber and applying heat to the mixture. It is particularly preferable that the starch, plasticizer, and crosslinker constitute starch composite particles. Such starch composite particles have thermoplastic properties and are reactive with the crosslinker. Therefore, by heating the mixture, the mycelia are physically bonded to each other, the mycelia and fiber, and the fiber to each other. Furthermore, by heating the mixture, the hydroxyl groups present in the mycelia, starch, plasticizer, and fiber react with the crosslinker, resulting in chemical bonding.

[0052] The mixing ratio of mycelia, fiber, and starch composite particles in the composite can be appropriately set depending on the application and required performance of the composite, and can be expressed, for example, by the total content of starch, plasticizer, and crosslinking agent in the composite, and the ratio of mycelia content to fiber content.

[0053] The total content of starch, plasticizer, and crosslinking agent in the composite is preferably 1.0% to 90.0% by mass, more preferably 1.5% to 85.0% by mass, even more preferably 1.5% to 80.0% by mass, and particularly preferably 5.0% to 80.0% by mass. If the total content of starch, plasticizer, and crosslinking agent in the composite is within the above range, the mixing ratio of mycelia, fibers, and starch composite particles is optimized, and sufficient mechanical strength, moisture resistance, and texture are obtained.

[0054] The mass ratio of the mycelia content to the fiber content is preferably 0.10 to 9.0, more preferably 0.20 to 5.0, and even more preferably 0.30 to 3.0. If the ratio of the mycelia content to the fiber content is within the above range, a good balance between high mechanical strength and good texture can be achieved in the composite.

[0055] If the mass ratio of the mycelia content to the fiber content is below the lower limit, the texture of the composite may be deteriorated, whereas if the mass ratio of the mycelia content to the fiber content is above the upper limit, the mechanical strength of the composite may be deteriorated.

[0056] The composite may also contain any additives, such as antioxidants, ultraviolet absorbers, lubricants, flame retardants, antistatic agents, and fillers, and one or more of these may be used.

[0057] 1.8. Dispersion of starch composite particles in the composite In the composite, the starch composite particles are preferably dispersed among the mycelia and fibers. The dispersed state refers to a state in which the starch composite particles are scattered between the mycelia, between the fibers, and between the mycelia and the fibers. As described above, the composite is heated and molded. Therefore, in the composite, the starch composite particles exist in a solidified state after plasticization.

[0058] Figure 1 is a conceptual diagram of starch composite particles BM dispersed in mycelia MC and fiber CF. As shown in Figure 1, in the composite, the starch composite particles BM lose their particle shape before melting and exist in a state where they stick to the mycelia MC and fiber CF. In this state, the mycelia MC, the fiber CF, and the mycelia MC and fiber CF are physically bound together and chemically bonded by the crosslinking agent, fixing their relative positions. In other words, the mycelia MC, the fiber CF, and the mycelia MC and fiber CF are strongly bound together via the starch composite particles BM. This fixes and maintains the external shape of the composite, allowing it to maintain a desired shape, such as a sheet. Furthermore, the mycelia MC and fiber CF spread out in an intertwined manner, imparting a pleasant texture to the composite.

[0059] In addition, the composite may contain unbound mycelia MC and fiber CF, and the proportion thereof can be adjusted by the amount of starch composite particles. The more unbound mycelia MC and fiber CF there are, the more easily deformed the composite will be. Furthermore, the more bound portions there are, the higher the rigidity and mechanical strength of the composite will be.

[0060] 1.9. Uses of the Complex The composite can be molded into various shapes as needed. The composite can be molded into two-dimensional shapes such as a sheet, board, or web, or three-dimensional shapes such as a block, rod, or sphere. Typical examples of composites include paper, nonwoven fabric, wallpaper, wrapping paper, colored paper, drawing paper, fiberboard, filters, liquid absorbents, sound absorbers, cushioning materials, mats, etc.

[0061] The composite according to this embodiment has excellent mechanical strength, moisture resistance, and texture, and is therefore particularly useful as a naturally derived material, such as a leather substitute (alternative leather).

[0062] 2. Manufacturing method of the composite Next, a method for producing the composite according to the embodiment will be described. FIG. 2 is a process diagram showing the steps of a method for producing a composite according to an embodiment.

[0063] The method for producing a composite shown in FIG. 2 includes a fiber-opening step S102 and a mixing step S104.

[0064] 2.1. Defibration process In the defibration step S102, the mushroom mycelium is defibrated, thereby loosening the mycelium and allowing the mycelium to be extracted.

[0065] Mycelium is an aggregate of hyphae. For example, a method of applying mechanical energy is used to defibrate mycelium. In particular, by using a defibrator, it is possible to defibrate mycelium and obtain hyphae while suppressing significant damage to the hyphae. The defibration method may be a wet method, but a dry method is preferably used. A dry method refers to a method in which defibration is carried out in air such as the atmosphere, rather than in a liquid such as water. An impeller mill capable of dry defibration is preferably used as the defibrator.

[0066] 2.2.Mixing process In the mixing step S104, the mycelium, starch, plasticizer, cross-linking agent, and fibers are mixed together to obtain a composite.

[0067] For mixing, various types of agitators can be used, such as a mechanical agitator, an air current agitator, an ultrasonic agitator, and the like.

[0068] The timing of mixing the above components may be the same for each component or may be different for each component. For example, two or more components may be mixed simultaneously, or each component may be mixed sequentially.

[0069] The obtained composite may be molded as necessary, thereby obtaining a composite having a desired shape.

[0070] 3. Composite manufacturing equipment Next, an example of a manufacturing apparatus to which the above manufacturing method is applied will be described.

[0071] FIG. 3 is a diagram schematically illustrating an example of a composite manufacturing apparatus 100 for manufacturing a composite according to an embodiment.

[0072] The composite manufacturing apparatus 100 shown in FIG. 3 has a supply section 10, a crushing section 12, a defibrating section 20, a sorting section 40, a first web forming section 45, a rotating body 49, a mixing section 50, a deposition section 60, a second web forming section 70, a composite forming section 80, a cutting section 90, and a humidifying section 78.

[0073] The supply unit 10 supplies raw material to the crushing unit 12. The supply unit 10 is, for example, an automatic feeding unit for continuously feeding raw material into the crushing unit 12. The raw material fed to the crushing unit 12 may be any material as long as it contains fiber.

[0074] The crushing unit 12 cuts the raw material supplied by the supply unit 10 into small pieces in the atmosphere (air) or other air. The small pieces have a shape and size of, for example, several centimeters square. In the example shown in the figure, the crushing unit 12 has crushing blades 14, which can cut the input raw material. A shredder, for example, is used as the crushing unit 12. The raw material cut by the crushing unit 12 is received in a hopper 1 and then transferred (conveyed) to the defibrating unit 20 via a pipe 2.

[0075] The defibrating unit 20 defibrates the raw material and mushroom mycelium cut by the crushing unit 12. The defibrating unit 20 also has the function of separating substances such as resin particles, ink, toner, fillers, and anti-bleeding agents adhering to the raw material from the fibers.

[0076] The material that has passed through the defibrating unit 20 is called the "defibrated material." In addition to the defibrated fibers and mycelium, the "defibrated material" may also contain additives such as resin particles that have separated when the fibers are defibrated, coloring agents such as ink, toner, and pigments, and anti-bleeding agents and paper strength agents.

[0077] The defibrator unit 20 performs dry defibration. The defibrator unit 20 has the function of generating an airflow that sucks in raw materials, mycelium, etc. and discharges the defibrated material. This allows the defibrator unit 20 to suck in raw materials, etc. together with the airflow from the inlet 22 using the airflow it generates, defibrates the materials, and transports the defibrated material to the outlet 24. The defibrated material that has passed through the defibrator unit 20 is transferred to the sorting unit 40 via the pipe 3. The airflow for transporting the defibrated material from the defibrator unit 20 to the sorting unit 40 may be the airflow generated by the defibrator unit 20, or an airflow generating device such as a blower may be provided and that airflow may be used.

[0078] The sorting unit 40 introduces the defibrated material defibrated by the defibrator unit 20 through an inlet 42 and sorts it by fiber length. The sorting unit 40 has a drum unit 41 and a housing unit 43 that houses the drum unit 41. The drum unit 41 is, for example, a sieve. The drum unit 41 has a mesh (filter, screen) and can separate fibers or particles smaller than the mesh opening size (first sorted material that passes through the mesh) from fibers larger than the mesh opening size, undefibrated pieces, and lumps (second sorted material that do not pass through the mesh). For example, the first sorted material is transferred to the mixing unit 50 via pipe 7. The second sorted material is returned to the defibrator unit 20 from a discharge port 44 via pipe 8. Specifically, the drum unit 41 is a cylindrical sieve that is rotated by a motor. The mesh of the drum portion 41 may be, for example, a wire mesh, an expanded metal made by stretching a metal plate with slits, or a punched metal made by forming holes in a metal plate with a press or the like.

[0079] The first web forming section 45 transports the first sorted material that has passed through the sorting section 40 to the mixing section 50. The first web forming section 45 includes a mesh belt 46, a tension roller 47, and a suction section 48 (suction mechanism).

[0080] The suction unit 48 sucks the first sorted material that has passed through the openings (net openings) of the sorting unit 40 and dispersed in the air onto the mesh belt 46. The first sorted material is deposited on the moving mesh belt 46 and forms a web V. The basic configurations of the mesh belt 46, tension roller 47, and suction unit 48 are similar to those of the mesh belt 72, tension roller 74, and suction mechanism 76 of the second web forming unit 70, which will be described later.

[0081] The web V is formed into a soft, puffy state containing a lot of air by passing through the sorting section 40 and the first web forming section 45. The web V deposited on the mesh belt 46 is fed into the pipe 7 and transported to the mixing section 50.

[0082] The rotating body 49 can cut the web V before the web V is transported to the mixing section 50. In the example shown, the rotating body 49 has a base 49a and protrusions 49b protruding from the base 49a. The protrusions 49b have, for example, a plate-like shape. In the example shown, four protrusions 49b are provided, and the four protrusions 49b are provided at equal intervals. When the base 49a rotates in the direction R, the protrusions 49b rotate around the base 49a as an axis. By cutting the web V with the rotating body 49, it is possible to reduce fluctuations in the amount of defibrated material supplied to the deposition section 60 per unit time, for example.

[0083] The rotating body 49 is provided near the first web forming unit 45. In the illustrated example, the rotating body 49 is provided near the tension roller 47a located downstream in the path of the web V. The rotating body 49 is provided at a position where the protrusions 49b can come into contact with the web V but do not come into contact with the mesh belt 46 on which the web V is deposited. The shortest distance between the protrusions 49b and the mesh belt 46 is, for example, not less than 0.05 mm and not more than 0.5 mm.

[0084] The mixing section 50 mixes the first sorted material that has passed through the screening section 40 with an additive containing starch composite particles. The mixing section 50 has an additive supply section 52 that supplies the additive, a pipe 54 that transports the first sorted material and the additive, and a blower 56. In the example shown in the figure, the additive is supplied from the additive supply section 52 to the pipe 54 via a hopper 9. The pipe 54 is continuous with the pipe 7.

[0085] In the mixing section 50, an air current is generated by a blower 56, and the first sorted material and the additives can be transported while being mixed in the pipe 54. The mechanism for mixing the first sorted material and the additives is not particularly limited, and may be one that uses a blade that rotates at high speed to mix the materials, or one that uses the rotation of a container, such as a V-type mixer.

[0086] The additive supply unit 52 may be a screw feeder as shown in FIG. 5 or a disk feeder (not shown). The additives supplied from the additive supply unit 52 include the above-mentioned starch composite particles BM. When the starch composite particles BM are supplied, the fibers and hyphae are not bound to them. The starch composite particles BM are plasticized and cross-linked as they pass through the composite formation unit 80, thereby binding the fibers and hyphae to form the composite WS.

[0087] If the starch composite particles BM do not contain a crosslinking agent, the crosslinking agent is supplied as the additive. For example, if the crosslinking agent is in powder form, the starch composite particles BM and the crosslinking agent can be supplied from the additive supply unit 52. On the other hand, if the crosslinking agent is in liquid form, a sprayer or the like can be provided somewhere before the heating unit 84 so that the crosslinking agent can be sprayed onto the fibers.

[0088] The additives supplied from the additive supply unit 52 may contain, in addition to the starch composite particles BM, a colorant for coloring the fibers, an aggregation inhibitor for inhibiting aggregation of the fibers and hyphae and aggregation of the starch composite particles BM, and a flame retardant for making the fibers, etc., less flammable, depending on the type of composite WS to be produced. The mixture (a mixture of the first sorted material and the additives) that has passed through the mixing unit 50 is transferred to the deposition unit 60 via a pipe 54.

[0089] The depositing unit 60 introduces the mixture that has passed through the mixing unit 50 from an inlet 62, loosens the tangled defibrated material, and drops it down while dispersing it in the air. This allows the depositing unit 60 to deposit the mixture uniformly in the second web forming unit 70.

[0090] The deposition unit 60 has a drum unit 61 and a housing unit 63 that houses the drum unit 61. A rotating cylindrical sieve is used as the drum unit 61. The drum unit 61 has a mesh and causes fibers, hyphae, or particles that are smaller than the mesh size and are contained in the mixture that has passed through the mixing unit 50 to fall. The configuration of the drum unit 61 is the same as that of the drum unit 41, for example.

[0091] The "sieve" of the drum unit 61 does not have to have the function of separating out a specific object. In other words, the drum unit 61 may simply allow the entire mixture introduced therein to fall.

[0092] The second web forming unit 70 deposits the material that has passed through the depositing unit 60 to form a web W, which is a deposit that will become the composite WS. The second web forming unit 70 has, for example, a mesh belt 72, a tension roller 74, and a suction mechanism 76.

[0093] As the mesh belt 72 moves, it deposits materials that have passed through the openings (net openings) of the depositing section 60. The mesh belt 72 is stretched by tension rollers 74, and is configured to prevent materials from passing through while allowing air to pass through. The mesh belt 72 moves as the tension rollers 74 rotate. As the mesh belt 72 moves continuously, materials that have passed through the depositing section 60 continuously fall and accumulate, forming a web W on the mesh belt 72. The mesh belt 72 is made of, for example, metal, resin, cloth, or nonwoven fabric.

[0094] The suction mechanism 76 is provided below the mesh belt 72 (on the opposite side from the deposition unit 60). The suction mechanism 76 can generate a downward airflow (an airflow directed from the deposition unit 60 toward the mesh belt 72). The suction mechanism 76 can suck the mixture dispersed in the air by the deposition unit 60 onto the mesh belt 72. This can increase the discharge speed from the deposition unit 60. Furthermore, the suction mechanism 76 can form a downflow in the falling path of the mixture, which can prevent the defibrated material and additives from becoming entangled during the fall.

[0095] The composite forming unit 80 heats the web W deposited on the mesh belt 72 to form composites WS. In the composite forming unit 80, heat is applied to the deposit (web W) of the mixture of defibrated material and additives mixed in the web W, thereby plasticizing and cross-linking the starch composite particles BM. Thereafter, the starch composite particles BM physically and chemically bind the multiple cellulose fibers together.

[0096] The complex forming section 80 includes a heating section 84 that heats the web W. For example, a heat press or a heating roller (heater roller) can be used as the heating section 84, but the following description will be given using an example in which a heating roller (heater roller) is used. The number of heating rollers in the heating section 84 is not particularly limited. In the illustrated example, the heating section 84 includes a pair of heating rollers 86. By configuring the heating section 84 as heating rollers 86, the complex WS can be formed while continuously transporting the web W. The heating rollers 86 are arranged, for example, so that their rotation axes are parallel to each other.

[0097] The heating rollers 86 come into contact with the web W and heat the web W while sandwiching and transporting the web W. The heating rollers 86 sandwich and transport the web W to form a composite WS of a predetermined thickness. The pressure applied to the web W by the heating rollers 86 can be adjusted depending on the composite WS to be produced.

[0098] The surface temperature of the heating roller 86 when heating the web W is set appropriately depending on the plasticization temperature of the starch composite particles BM and the reaction temperature of the crosslinking agent, and is, for example, 60.0°C or higher and 250.0°C or lower, preferably 70.0°C or higher and 220.0°C or lower, and more preferably 80.0°C or higher and 200.0°C or lower.

[0099] Such a composite manufacturing apparatus 100 can manufacture the composite WS (the composite according to the embodiment).

[0100] The composite manufacturing apparatus 100 may have a cutting section 90 as needed. In the illustrated example, the cutting section 90 is provided downstream of the heating section 84. The cutting section 90 cuts the composite WS formed by the composite forming section 80. In the illustrated example, the cutting section 90 has a first cutting section 92 that cuts the composite WS in a direction intersecting the conveyance direction of the composite WS, and a second cutting section 94 that cuts the composite WS in a direction parallel to the conveyance direction. The second cutting section 94 cuts the composite WS that has passed through the first cutting section 92, for example.

[0101] The composite production apparatus 100 may also have a humidifying unit 78. In the illustrated example, the humidifying unit 78 is provided downstream of the cutting unit 90 and upstream of the discharge unit 96. The humidifying unit 78 can apply water or water vapor to the composite WS. Specific embodiments of the humidifying unit 78 include, for example, spraying a mist of water or an aqueous solution, spraying water or an aqueous solution, and ejecting water or an aqueous solution from an inkjet head to deposit the water or aqueous solution.

[0102] The composite manufacturing apparatus 100 has a humidifying unit 78, which allows the formed composite WS to be moistened. This allows the fibers and hyphae to become moist and soft. Therefore, when the composite WS is used to form a three-dimensional container or the like, wrinkles and tears are even less likely to occur. Furthermore, by moistening the composite WS, hydrogen bonds are more likely to form between the fibers and hyphae, which increases the density of the molded container or the like, thereby improving, for example, the mechanical strength.

[0103] Since the starch composite particles are plasticized by heat and a cross-linking reaction occurs, the composite can be formed in a dry process. Therefore, the humidifying unit 78 is not necessarily required for the composite production apparatus 100. However, a humidifying unit may be placed at an appropriate location in the hope of forming hydrogen bonds between fibers or mycelia.

[0104] In this way, the composite WS is formed. The produced composite WS is cut, for example, by a cutting unit 90, and the composite WS is discharged to a discharge unit 96 as necessary. Alternatively, the composite WS may be wound into a roll without being cut.

[0105] In the above example, an example of producing a sheet-shaped composite WS was shown, but by changing the heating section, deposition section, etc., it is also possible to form a three-dimensional composite.

[0106] 4. Modifications of the manufacturing method of the composite Next, a modified example of the method for producing a composite according to the embodiment will be described.

[0107] FIG. 4 is a process diagram showing the configuration of a modified example of the method for producing a composite according to the embodiment. The method for producing the complex shown in FIG. 4 includes a medium preparation step S202, an inoculum inoculation step S204, and a culture step S206.

[0108] 4.1. Medium preparation process In the medium preparation step S202, a medium containing starch, a plasticizer, a cross-linking agent, and fiber is prepared. In addition to these components, the medium may also contain nutrients necessary for the growth of mushroom mycelia, a gelling agent, etc. Alternatively, starch may be used as a nutrient.

[0109] The medium may be a solid medium or a liquid medium. Of these, the solid medium is formed by molding a mixture containing, for example, starch, a plasticizer, a crosslinking agent, fibers, etc. into a predetermined shape. It is preferable to mold the mixture into the shape of the composite to be produced. This allows a composite of the desired shape to be efficiently produced without any secondary processing. The solid medium may be formed, for example, by removing the mycelia from the composite described above and adding additives such as nutrients. The liquid medium may be prepared by dispersing starch, plasticizer, crosslinking agent, fiber, etc. in a dispersion medium such as water. The liquid medium may be prepared by removing mycelia from the above-mentioned complex and adding additives such as nutrients and a dispersion medium.

[0110] 4.2. Seed inoculation process In the seed inoculation step S204, the medium is inoculated with a mycelium seed. The inoculation method is not particularly limited.

[0111] For example, when inoculating a solid medium, the inoculum may be placed on the surface of the solid medium or embedded inside the medium, and may be arranged at equal or random intervals. When inoculating a liquid medium, the liquid medium to which the seed culture has been added may be stirred.

[0112] 4.3.Culture process In the culturing step S206, the seed culture medium is inoculated and cultured to obtain a composite. This allows mycelia to grow from the seed culture medium, resulting in a composite in which the mycelia are spread throughout the medium. The mycelia also form a three-dimensional network. In the case of a solid culture medium, this allows the mycelia to fill the voids present in the medium, imparting the flexible mechanical properties inherent in the mycelium to the composite. When a solid culture medium is used, the resulting composite can be used as is. On the other hand, in the case of a liquid culture medium, solid-liquid separation may be performed after culturing to remove the liquid components. When a liquid culture medium is used, the medium is relatively easy to manage and handle due to its liquid state. Furthermore, liquid culture medium allows for operations such as stirring, making it easy to homogenize and speed up the culture. Culture conditions such as culture temperature, culture time, and humidity are appropriately set depending on the type of mycelium and medium.

[0113] Alternatively, the solid portion of the liquid medium obtained after solid-liquid separation after cultivation, or the liquid medium itself after cultivation, can be poured onto the surface of a separately prepared solid medium. This allows a certain amount of cultured mycelia to be transplanted onto the solid medium. As a result, a composite that combines the good mechanical strength and moisture resistance inherent in the solid medium with the good texture inherent in the mycelia can be produced in a relatively short time.

[0114] The obtained composite may be molded as necessary, thereby obtaining a composite having a desired shape.

[0115] 5. Effects of the above embodiment As described above, the composite according to the embodiment includes mushroom mycelia, starch, a plasticizer, a cross-linking agent, and fibers.

[0116] According to this configuration, a composite body having excellent mechanical strength and moisture resistance and a good texture can be obtained.

[0117] The composite according to the embodiment includes particulate starch composite particles, which contain starch and a plasticizer.

[0118] This structure allows the starch and plasticizer to be distributed evenly, which makes the composite homogenous and improves the moisture resistance and mechanical strength of the composite.

[0119] In the composite according to the embodiment, the crosslinking agent is contained in the starch composite particles. This configuration allows the starch composite particles to be well held, thereby improving the moisture resistance and mechanical strength of the composite.

[0120] In the composite according to the embodiment, the average particle size of the starch composite particles is 1 μm or more and 60 μm or less.

[0121] This configuration makes it easier for the starch composite particles to be more uniformly dispersed among the hyphae and fibers in the composite, resulting in a composite with even better mechanical strength, moisture resistance, and texture.

[0122] In the composite according to the embodiment, the fibers contain cellulose. According to this configuration, since cellulose contains many hydroxyl groups in its molecular structure, it is easy to react with the crosslinking agent, and the mechanical strength and moisture resistance of the composite are easily improved.

[0123] In the composite according to the embodiment, the crosslinking agent crosslinks with the starch via the plasticizer.

[0124] According to this configuration, the cross-linking agent contributes to cross-linking of the mycelium, starch, plasticizer and fibers, thereby improving the mechanical strength, moisture resistance and texture of the composite.

[0125] In the composite according to the embodiment, the cross-linking agent cross-links the mycelium. This configuration can particularly improve the texture of the composite.

[0126] In the composite according to the embodiment, the mycelia have an average diameter of 0.1 μm or more and 10.0 μm or less. This configuration can particularly enhance the texture of the composite.

[0127] In the composite according to the embodiment, the fibers have an average diameter of 1.0 μm or more and 100.0 μm or less. With this configuration, the mechanical strength of the composite can be particularly increased.

[0128] In the composite according to the embodiment, the mass ratio of the mycelia content to the fiber content is 0.10 or more and 9.0 or less.

[0129] This configuration allows the composite to have a good balance between high mechanical strength and good texture.

[0130] In the composite according to the embodiment, the total content of the starch, the plasticizer, and the crosslinking agent is 1.0% by mass or more and 90.0% by mass or less. With this configuration, the composite can have sufficient mechanical strength.

[0131] In the composite according to the embodiment, the plasticizer is one or more selected from sugar alcohols.

[0132] This configuration allows the starch to be plasticized more easily, which makes it easier for the starch composite particles to bind together hyphae, fibers, and hyphae and fibers, thereby imparting better strength to the composite.

[0133] In the complex according to the embodiment, the sugar alcohol is one or more selected from sorbitol, erythritol, and D-mannitol.

[0134] This configuration allows for easier plasticization of starch, and since no plasticization occurs at room temperature, handling during the manufacturing process and of the manufactured composite is facilitated. As a result, the starch composite particles are more likely to bind together with each other, with each other, and with each other, and can impart better mechanical strength to the composite.

[0135] In the composite according to the embodiment, the mass ratio of the content of the plasticizer to the total content of the plasticizer and the starch is 0.05 or more and 0.90 or less.

[0136] According to this configuration, the starch is plasticized more sufficiently, and the composite can be provided with better mechanical strength.

[0137] In the composite according to the embodiment, the crosslinking agent is one or more selected from dicarboxylic acids.

[0138] This structure allows the mycelium, starch, plasticizer, and fiber to be chemically crosslinked, thereby improving the mechanical strength, moisture resistance, and texture of the composite.

[0139] In the composite according to the embodiment, the dicarboxylic acid is at least one selected from succinic acid, adipic acid, and sebacic acid.

[0140] According to this configuration, chemical cross-linking is formed by ester bonds, which further improves the mechanical strength, moisture resistance, and texture of the composite.

[0141] The method for producing a composite according to the embodiment includes a defibrating step S102 and a mixing step S104. In the defibrating step S102, mushroom mycelium is defibrated to obtain mycelium. In the mixing step S104, mycelium, starch, a plasticizer, a crosslinking agent, and fibers are mixed to obtain a composite.

[0142] According to this configuration, a composite body having excellent mechanical strength and moisture resistance and a good texture can be produced.

[0143] Furthermore, the method for producing a composite according to the embodiment includes a medium preparation step S202, an inoculum inoculation step S204, and a culture step S206. The medium preparation step S202 prepares a medium containing starch, a plasticizer, a crosslinker, and fibers. The inoculum inoculation step S204 inoculates a mycelium inoculum into the medium. The culture step S206 cultures the inoculum to obtain a composite.

[0144] This method allows the production of a composite with excellent mechanical strength, moisture resistance, and texture. Furthermore, the mycelia form a three-dimensional network and can fill the voids in the medium, imparting the flexible mechanical properties inherent to the mycelium to the composite.

[0145] Furthermore, the method for producing a complex according to the embodiment is a solid medium or a liquid medium. According to this configuration, when a solid medium is used, the obtained complex can be used as is, whereas when a liquid medium is used, the medium is relatively easy to manage and handle.

[0146] The composite and the method for producing the composite of the present invention have been described above based on preferred embodiments, but the present invention is not limited thereto. For example, the composite of the present invention may be one in which each part of the embodiment is replaced with any component having the same function, or one in which any component is added to the embodiment.

[0147] Furthermore, the method for producing the composite of the present invention may be one in which any step for any purpose is added to the above-described embodiment. [Example]

[0148] Next, specific examples of the present invention will be described. 6. Preparation of starch composite particles The starch composite particles used in each Example and Comparative Example were produced as follows. Figures 5 to 11 are Tables 1 to 7 showing the structure of the composites in each Example and Comparative Example and the structure of the starch composite particles used to produce the composites. Figures 5 (Table 1) to 7 (Table 3) and 11 (Table 7) show examples in which starch composite particles containing a crosslinking agent were produced. However, Example 55 is an example in which no starch composite particles were used. Figures 8 (Table 4) to 10 (Table 6) show examples in which starch composite particles not containing a crosslinking agent were produced.

[0149] 6.1. When succinic acid or citric acid is contained as a plasticizer First, oxidized starch (SK200, manufactured by Japan Corn Starch Co., Ltd.) as the starch, a plasticizer, succinic acid or citric acid (Fujifilm Wako Pure Chemical Industries, Ltd.) as the crosslinking agent, and water were mixed and heated and stirred at 100°C for 2 hours to prepare a starch gelatinized solution. The resulting starch gelatinized solution was spray-dried using a spray dryer (ADL311S-A, manufactured by Yamato Scientific Co., Ltd.) at an inlet temperature of 150°C and an outlet temperature of 70°C to obtain starch composite particles.

[0150] 6.2. When adipic acid or sebacic acid is contained as a plasticizer First, oxidized starch (SK200, manufactured by Nippon Corn Starch Co., Ltd.) as starch, a plasticizer, and water were mixed, and the mixture was heated and stirred at 100° C. for 2 hours to prepare a starch gelatinized liquid.

[0151] Separately, 2% by mass of adipic acid or sebacic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was mixed with ethanol (manufactured by Tokyo Chemical Industry Co., Ltd.) to prepare an ethanol solution of adipic acid and an ethanol solution of sebacic acid.

[0152] Then, the starch gelatinized liquid and the adipic acid ethanol solution or the sebacic acid ethanol solution were mixed at a mass ratio of 1:1 to obtain a mixed liquid.

[0153] The resulting mixture was spray-dried using a spray dryer (Yamato Scientific Co., Ltd., ADL311S-A) at an inlet temperature of 150°C and an outlet temperature of 70°C to obtain starch composite particles.

[0154] 6.3. When the starch composite particles do not contain a crosslinking agent First, oxidized starch (SK200, manufactured by Nippon Corn Starch Co., Ltd.) was mixed with a plasticizer and water, and the mixture was heated and stirred at 100°C for 2 hours to prepare a gelatinized starch solution. The resulting gelatinized starch solution was spray-dried using a spray dryer (ADL311S-A, manufactured by Yamato Scientific Co., Ltd.) at an inlet temperature of 150°C and an outlet temperature of 70°C to obtain starch composite particles (thermoplastic starch).

[0155] 6.4. Composition of Starch Composite Particles The compositions of the obtained starch composite particles are shown in Figure 5 (Table 1) to Figure 11 (Table 7). Each table also lists the plasticizer / (starch-plasticizer) ratio, crosslinker / (starch-plasticizer-crosslinker) ratio, and average particle size of the starch composite particles. The average particle size was measured using a particle size distribution analyzer (Microtrac MT3000II, manufactured by Nikkiso Co., Ltd.). Starch composite particles with different particle sizes were produced by spray-drying, adjusting the feed rate of the mixed liquid (gelatinized liquid), inlet temperature, outlet temperature, residence time, atomizer rotation speed, spray pressure, and other parameters.

[0156] In Example 55, the starch composite particles were not used, and the starch, plasticizer, and crosslinker were mixed separately. In Table 7, the content of the starch composite particles in Example 55 is underlined, but this indicates the total amount of each component, not the content of the starch composite particles.

[0157] 7. Complex Preparation Mycelia, starch composite particles, crosslinking agent, and fiber were mixed to the mixing ratios shown in Tables 1 to 7. The mycelia used were shiitake mycelia with an average diameter of 3.0 μm and an average length of 0.1 mm, or polyporus mycelia with an average diameter of 5.0 μm and an average length of 0.5 mm. The raw material for the fiber was cellulose fiber with an average diameter of 30 μm and an average length of 1.0 mm.

[0158] 7.1. Preparation of sheet composite A Sheet composite A was produced as follows: First, the mixture of each example was hot-pressed at 150° C. for 2 minutes under a pressure of 90 MPa, thereby obtaining a sheet-shaped sample (sheet composite A).

[0159] 7.2. Preparation of sheet-like composite B Sheet composite B was produced as follows: First, the mixture of each example was hot-pressed at 180°C for 6 minutes under a pressure of 1 MPa, thereby producing a sample (sheet composite B) with a lower density than sheet composite A.

[0160] 8. Evaluation of the Complex 8.1. Tensile index First, the sheet composite A was punched out to prepare test specimens. Next, using an AUTOGRAPH AGC-X 500N (Shimadzu Corporation), the test specimens were subjected to a tensile property test in accordance with JIS P 8113:2006 to determine the tensile index. The determined values ​​were evaluated according to the following evaluation criteria. The evaluation results are shown in the tables.

[0161] A: tensile strength is 15 N·m / g or more B: Specific tensile strength is 10 N·m / g or more and less than 15 N·m / g C: Specific tensile strength is 5 N·m / g or more and less than 10 N·m / g D: Specific tensile strength is less than 5 N·m / g

[0162] 8.2. Moisture resistance First, sheet composite B was cut into a rectangular parallelepiped shape measuring 2 cm x 1 cm x 1 cm to prepare a test specimen. An aluminum plate was placed inside a thermo-humidistat chamber, and the test specimen was placed at each of its four corners. An 800 g aluminum plate was placed on top of the aluminum plate, applying a pressure of 0.01 MPa. After measuring the initial gap between the aluminum plates, the thermo-humidistat chamber was heated and humidified to 60°C and 90% RH. After 120 hours, the gap between the aluminum plates was measured again, and the displacement rate from the initial gap (compression creep rate) was calculated. The calculated values ​​were then evaluated according to the following evaluation criteria. The evaluation results are shown in the tables.

[0163] A: Compressive creep rate is less than 5% B: Compression creep rate is 5% or more but less than 10% C: Compression creep rate is 10% or more but less than 20% D: Compression creep rate is 20% or more

[0164] 8.3.Texture A sensory evaluation of sheet composite B was conducted by a panel of 10 people (evaluators). The sensory evaluation was conducted in accordance with the ranking method for sensory evaluation analysis in JIS Z 9080:2004. Specifically, the 10 people evaluated the tactile feel of the surface of sheet composite B in accordance with the 9-point preference scale specified in JIS Z 9080:2004. The tactile feel particularly refers to the degree of smoothness and pleasant feel to the touch. The obtained preference scale was then evaluated in accordance with the following evaluation criteria. The evaluation results are shown in the tables. In the 9-point preference scale, 9 represents the most pleasant and 1 represents the most unpleasant.

[0165] A: A preference scale of 8 to 9 B: Preference scale score is 6-7 C: Preference scale score is 4-5 D: Preference scale is 1-3

[0166] 8.4. Discussion From the evaluation results shown in Tables 1 to 7, the following can be seen. By incorporating mushroom mycelium, starch, plasticizer, cross-linking agent, and fiber, a composite with excellent mechanical strength, moisture resistance, and texture was realized. In particular, it was found that the use of starch composite particles can further improve mechanical strength, moisture resistance, and texture. [Explanation of symbols]

[0167] 1...hopper, 2...pipe, 3...pipe, 7...pipe, 8...pipe, 9...hopper, 10...feeding section, 12...crushing section, 14...crushing blade, 20...defibrating section, 22...inlet, 24...discharge outlet, 40...sorting section, 41...drum section, 42...inlet, 43...housing section, 44...discharge outlet, 45...first web forming section, 46...mesh belt, 47...tensioning roller, 47a...tensioning roller, 48...suction section, 49...rotating body, 49a...base section, 49b...projection section, 50...mixing section, 52...additive supplying section, 54...pipe, 56...blower, 60...accumulation section, 61...drum section, 62...inlet , 63...housing section, 70...second web forming section, 72...mesh belt, 74...tension roller, 76...suction mechanism, 78...humidifying section, 80...composite forming section, 84...heating section, 86...heating roller, 90...cutting section, 92...first cutting section, 94...second cutting section, 96...discharge section, 100...composite manufacturing device, BM...starch composite particle, CF...fiber, MC...mycelium, R...direction, S102...defibration process, S104...mixing process, S202...medium preparation process, S204...seed inoculation process, S206...cultivation process, V...web, W...web, WS...composite

Claims

1. A composite comprising mushroom mycelia, starch, a plasticizer, a cross-linking agent, and fibers.

2. The starch composition has a particulate shape.

2. The composite of claim 1, wherein the starch and the plasticizer are contained in the starch composite particles.

3. The composite of claim 2 , wherein the cross-linking agent is contained in the starch composite particles.

4. 4. The composite according to claim 2, wherein the average particle size of the starch composite particles is 1 μm or more and 60 μm or less.

5. 4. The composite of claim 1, wherein the fibers comprise cellulose.

6. 4. The composite according to claim 1, wherein the crosslinking agent is crosslinked with the starch via the plasticizer.

7. The complex according to claim 1 , wherein the cross-linking agent cross-links the mycelium.

8. 4. The complex according to claim 1, wherein the mycelium has an average diameter of 0.1 μm or more and 10.0 μm or less.

9. 4. The composite according to claim 1, wherein the fibers have an average diameter of 1.0 μm or more and 100.0 μm or less.

10. 4. The composite according to claim 1, wherein the mass ratio of the content of the mycelia to the content of the fibers is 0.10 or more and 9.0 or less.

11. 4. The composite according to claim 1, wherein the total content of the starch, the plasticizer, and the crosslinking agent is 1.0% by mass or more and 90.0% by mass or less.

12. The complex according to claim 1 , wherein the plasticizer is one or more selected from sugar alcohols.

13. 13. The complex according to claim 12, wherein the sugar alcohol is one or more selected from the group consisting of sorbitol, erythritol, and D-mannitol.

14. 4. The composite according to claim 1, wherein a mass ratio of a content of the plasticizer to a total content of the plasticizer and the starch is 0.05 or more and 0.90 or less.

15. The composite according to claim 1 , wherein the crosslinking agent is one or more selected from dicarboxylic acids.

16. 16. The complex according to claim 15, wherein the dicarboxylic acid is at least one selected from succinic acid, adipic acid, and sebacic acid.

17. A method for producing the composite of claim 1, comprising: A step of defibrating mushroom mycelium to obtain said mycelium; mixing the mycelia, the starch, the plasticizer, the cross-linking agent, and the fibers to obtain the composite; A method for producing a composite, comprising:

18. A method for producing the composite of claim 1, comprising: forming a medium having the starch, the plasticizer, the cross-linking agent, and the fiber; inoculating the medium with an inoculum of the mycelium; Cultivating the seed culture to obtain the complex; A method for producing a composite, comprising:

19. The method for producing a complex according to claim 18, wherein the medium is a solid medium or a liquid medium.

Images