JP7340848B2 - Leather-like material and its manufacturing method - Google Patents

Description

The present invention relates to a leather-like material and a method for producing the same, and more particularly, the present invention relates to a leather-like material and a method for producing the same, and more particularly, the present invention relates to a fungal cell fragment or cell paper product (fungal paper-like material) of a filamentous fungus containing chitin and/or chitosan in the cell wall, which has been aerated and liquid cultured. A leather-like material consisting of a material) in which the crushed microbial cells or paper-like material (paper-like material of microbial cells) has been deacetylated and plasticized, and Regarding the manufacturing method.

Leather is classified into natural leather and artificial leather. Natural leather generally refers to those made by peeling the skin of an animal and using it as a product (skin), and that made by removing the hair from the animal skin and tanning it (leather).In general, artificial leather refers to , those made from natural fabric coated with synthetic resin (synthetic leather), and those made from microfiber fabric such as non-woven fabric impregnated with synthetic resin, or those made from microfiber fabric such as non-woven fabric coated with synthetic resin (artificial leather). ). Traditionally, leather has been used for a wide variety of applications, including clothing, bags, shoes, interior decoration, furniture, accessories, and automobiles, and the global demand for leather is expected to reach US$629.6 billion by 2025. It is estimated that (Leather Goods Market Size, Share & Trends Analysis Report, By Distribution Channel (E-commerce, Retail Stores), By Pro duct (Footwear, Luggage, Accessories, Others), By Material And Segment Forecasts, 2019 - 2025 , Grand View Research, Inc.).

The animals that can be made from natural leather include a wide variety of biological resources, including mammals, reptiles, birds, and fish.However, biological resources are absolutely limited, and from an animal welfare perspective, it is difficult to use natural leather. Therefore, it is impossible and undesirable to meet the global demand mentioned above. On the other hand, it may become difficult in the future to meet the above-mentioned global demand with artificial leather made from synthetic resins, due to the depletion of fossil resources and the prevention of global warming. Therefore, in order to meet this demand while taking into account environmental, social and economic costs, alternative materials to leather have recently been developed using renewable biomass resources.

Chitin is a type of polysaccharide that is widely found in nature, such as in the exoskeleton of crustaceans such as shrimp and crabs, and in the cell walls of fungi.Chitosan is obtained by deacetylating chitin, but both are renewable biomass. It is a resource and is attracting attention as an alternative material to leather. For example, Patent Document 1 discloses a method for mass-producing chitin and/or chitosan from dermatophytes, and Patent Documents 2 and 3 disclose a method for mass-producing chitin and/or chitosan from dermatophytes, and Patent Documents 2 and 3 disclose a method for producing basidiomycetes, a type of filamentous fungi, in a solid medium. A method for producing a mycelial material using chitin contained in the mycelium of fungi such as Basidiomycetes and Ganoderma lucidum is disclosed.

International Publication No. 1993/014216 pamphlet US Patent Application Publication No. 2009/0307969 US Patent Application Publication No. 2018/0014468

However, in order to produce mycelium material by the method disclosed in Patent Document 2, static culture is adopted, so a culture period of 21 to 45 days is required. The method used also uses solid culture, so it takes more than 10 days just to grow the mycelia, and more than 2 weeks if all manufacturing steps are included. Therefore, for mass production, it is necessary to significantly shorten at least the culture period. Furthermore, the reality is that such mycelium materials do not have enough tensile strength or elongation to withstand practical use.

Therefore, the present invention was made to solve the above-mentioned problems, and it is possible to efficiently produce mycelium material compared to conventional methods for producing mycelium material that employ static culture or solid culture. The purpose of the present invention is to provide a leather-like material from the mycelium material having a tensile strength and elongation rate that can withstand practical use.

As a result of intensive research, the present inventors cultivated filamentous fungi containing chitin and/or chitosan in their cell walls in large quantities through aeration and liquid culture, collected the resulting fungi, and crushed them (particularly by wet crushing) and/or Or, after paper-making to obtain a bacterial cell crush product or a bacterial cell paper product (a bacterial cell paper-like material), the obtained bacterial cell fragment or bacterial cell paper product (a bacterial cell paper-like material) is deacetylated. The method for producing mycelial material, which involves plasticizing the obtained deacetylated microbial cell material or microbial cell paper (paper-like material), employs conventional static culture or solid culture. The mycelium material can be produced in a short period of time compared to the conventional mycelium material production method, and the mycelium material produced by this production method is a leather-like material, and compared to conventional mycelium materials. They found that the tensile strength and elongation rate were improved, and completed the following inventions.

(1) A leather-like material consisting of a fungal cell fragment or a fungal paper product (fungal paper-like material) of a filamentous fungus containing chitin and/or chitosan in its cell wall, which has been aerated and liquid cultured, The above-mentioned leather-like material, which is obtained by deacetylating and plasticizing a crushed product or a paper-like product of bacterial cells.

(2) A leather-like material consisting of a fungal cell fragment or a fungal cell material (fungal paper-like material) of a filamentous fungus containing chitin and/or chitosan in its cell wall, which has been aerated and liquid-cultured, wherein the fungal cell The leather-like material is obtained by deacetylating, crosslinking, and plasticizing a crushed product or a paper-like product of bacterial cells.

(3) (i) An aeration/liquid culture step of aerating and liquid culturing filamentous fungi containing chitin and/or chitosan in their cell walls; (ii) crushing and/or forming the aerated and liquid-cultured filamentous fungal cells; (iii) a microbial cell crushing/paper-making step to obtain a microbial cell crush product or a microbial cell paper product (a microbial cell paper-like material); (iv) a deacetylation treatment step for obtaining a deacetylated product of the crushed bacterial cells or paper-like bacterial cells (bacteria paper-like material), (iv) the resulting crushed bacterial cells; or a plasticizing treatment step for obtaining a plasticized product of the deacetylated product by plasticizing the deacetylated product of the bacterial cell paper (i), ( A leather-like material produced by a method comprising steps ii), (iii) and (iv).

(4) (i) An aeration/liquid culture step of aerating and liquid culturing filamentous fungi containing chitin and/or chitosan in their cell walls; (ii) crushing and/or paper-making the aerated and liquid-cultured filamentous fungi; (iii) a microbial cell crushing/paper-making step to obtain a microbial cell crush product or a microbial cell paper product (a microbial cell paper-like material); (iv) a deacetylation treatment step for obtaining a deacetylated product of the crushed bacterial cells or paper-like bacterial cells (bacteria paper-like material), (iv) the resulting crushed bacterial cells; or a crosslinking treatment step for obtaining a crosslinked product of the deacetylated product by crosslinking the deacetylated product of the bacterial cell paper product (the bacterial paper-like material); (v) the deacetylation treatment obtained above; A plasticization treatment step of plasticizing a crosslinked product to obtain a plasticized product of the crosslinked product, the above steps (i), (ii), (iii), (iv) and (v) A leather-like material produced by a method including

(5) A product made from the leather-like material according to at least one of (1) to (4) as a raw material.

(6) An aeration/liquid culture step of aerating and liquid culturing filamentous fungi containing chitin and/or chitosan in their cell walls, and crushing and/or paper-making the aerated and liquid-cultured filamentous fungi to crush the cells. A bacterial cell crushing/paper-making step to obtain a bacterial cell material or a bacterial cell paper product (a bacterial cell paper-like material), and a deacetylation treatment of the obtained bacterial cell fragment or bacterial cell paper product (a bacterial cell paper-like material). , a deacetylation treatment step for obtaining a deacetylated product of the crushed bacterial cells or paper-like bacterial cells; A method for producing a leather-like material, comprising a plasticizing step of plasticizing a deacetylated product of the deacetylated product (like material) to obtain a plasticized product of the deacetylated product.

(7) An aeration/liquid culture step of aerating and liquid culturing filamentous fungi containing chitin and/or chitosan in their cell walls, and crushing and/or paper-making the aerated and liquid-cultured filamentous fungi to crush the cells. A bacterial cell crushing/paper-making step to obtain a bacterial cell material or a bacterial cell paper product (a bacterial cell paper-like material), and a deacetylation treatment of the obtained bacterial cell fragment or bacterial cell paper product (a bacterial cell paper-like material). , a deacetylation treatment step for obtaining a deacetylated product of the crushed bacterial cells or paper-like bacterial cells; a crosslinking treatment step of obtaining a crosslinked product of the deacetylated product by crosslinking the deacetylated product of A method for producing a leather-like material, comprising a plasticizing step of obtaining a plasticized product of the crosslinked product.

According to the leather-like material and the method for producing the same according to the present invention, mycelium material can be produced in a short period of time compared to conventional methods for producing mycelium material that employ static culture or solid culture. Furthermore, it is possible to provide a mycelium material that is a leather-like material and has improved tensile strength and elongation compared to conventional mycelium materials.

FIG. 1 is a flow diagram showing the steps of the first embodiment of the method for producing a leather-like material according to the present invention. It is a flow diagram showing the steps of a second embodiment of the method for producing a leather-like material according to the present invention. It is a flow diagram showing the steps of a third embodiment of the method for producing a leather-like material according to the present invention. It is a flowchart which shows the process of 4th Embodiment of the manufacturing method of the leather-like material based on this invention. It is a flowchart which shows the process of 5th Embodiment of the manufacturing method of the leather-like material based on this invention. FIG. 2 is a photographic diagram showing a cross section of a bacterial paper product (a bacterial paper-like material) produced as an intermediate product in the method for manufacturing a leather-like material according to the present invention. 1 is a photographic diagram showing a cross section of a leather-like material produced by the method for producing a leather-like material according to the present invention. 1 is a photographic diagram showing an enlarged cross section of a leather-like material produced by the method for producing a leather-like material according to the present invention. FIG. 2 is a photographic diagram showing a cross section of a mycelial membrane obtained by a method that includes a step of statically culturing filamentous fungi, which is a conventional method. FIG. 2 is a photographic diagram showing a cross section of a mycelium material produced using a mycelium membrane obtained by a conventionally employed method that includes a step of statically culturing filamentous fungi. FIG. 2 is a photographic diagram showing an enlarged cross section of a mycelium material prepared using a mycelial membrane obtained by a conventionally employed method that includes a step of statically culturing filamentous fungi.

Hereinafter, the leather-like material and the method for producing the same according to the present invention will be described in detail based on embodiments. A first embodiment of the leather-like material according to the present invention is made from crushed fungal cells or cell paper products (fungal paper-like material) of filamentous fungi containing chitin and/or chitosan in the cell wall, which have been aerated and liquid cultured. The leather-like material is obtained by deacetylating and plasticizing the crushed bacterial cells or paper-like bacterial cells, and the leather-like material according to the present invention. The first embodiment of the method for manufacturing a leather-like material according to the above, as shown in FIG. It has "deacetylation treatment step S3" and "(iv) plasticization treatment step S4". The leather-like material of the first embodiment has a tensile strength and elongation rate high enough to withstand practical use such as use in products, and the method for producing the leather-like material of the first embodiment is suitable for practical use such as use in products. Leather-like materials can be produced with acceptable tensile strength and elongation.

In the first embodiment, the "leather-like material" refers to a mycelium material that has a feel and grip similar to the leather described above, mainly natural leather (leather), and mainly refers to a mycelium material that has a texture and grip similar to natural leather (leather). ) The mycelium material is not particularly limited as long as it has a texture and grip similar to that of the material.

In the "leather-like material" of the first embodiment, as shown in FIG. It can be seen that the bacterial cells constituting the chemically treated product are aligned and stacked in a substantially oriented manner. On the other hand, as shown in FIG. It is clear that the bacterial cells constituting the cell are not stacked in substantially oriented alignment.

Note that in order to directly identify the "leather-like material" of the first embodiment by its structure and/or characteristics, a plurality of "leather-like materials" of the first embodiment are prepared and various methods are used. However, such tests require a large number of tests and require a large amount of time even for a single competent person skilled in the art. (Patent/Utility Model Examination Handbook Part II Chapter 2 Requirements for Claims 2205 A claim for an invention of a product must include a method for manufacturing the product. (See the bottom line of page 16 to lines 1 to 4 of page 17 of ``Judgment regarding ``impossible/impractical circumstances'' in examinations where In other words, in order to directly specify the "leather-like material" according to the first embodiment by its structure or characteristics, it would require unprofitable time and expense for a person skilled in the art at the time of filing, and such Requiring specific work to be done is extremely difficult for applicants who are pursuing the earliest possible filing date under the first-to-file system, given the rapid advancement of technology and the fierce competition on an international scale to obtain patents. (Supreme Court No. 1204 of 2012, page 10, or pages 10-11 of Supreme Court No. 2658 of 2012).

Next, the "filamentous fungi" in the first embodiment include Hawksworth et al., In, Ainsworth and Bisby's Dictionary of The Fungi, 8th edition, 1995, CAB International, bUniversity, Defined by Press, Cambridge, UK As such, all filamentous forms of fungi belonging to the subdivisions Eumycota and Oomycota are included. Also, filamentous fungi are generally characterized by a mycelial wall composed of chitin, cellulose, glucan, chitosan, mannan and other complex polysaccharides, their vegetative growth is by hyphal expansion, and carbon Metabolism is strictly aerobic.

In the first embodiment, "filamentous fungi containing chitin and/or chitosan in the cell wall" refers to, among the above-mentioned filamentous fungi, for example, Oomycetes, Ascomycetes, and Deuteromycetes. ), Basidiomycetes, and Zygomycetes, which contain chitin and/or chitosan in their cell walls, as well as white-rot fungi, brown-rot fungi, and the like. . Also, for example, Acremonium genus, Aspergillus genus, Aureobasidium genus, Bjerkandera genus, Cellulomonas genus, Ceriporiopsis genus, Choanephora genus, Chrysosporium genus, Clostr. idium, Coprinus, Coriolus, Cryptococcus, Filibasidium, Fusarium, Humicola, Irpex Genus, Magnaporthe, Mucor, Myceliophthora, Neocallimastix, Neurospora, Paecilomyces, Parasitella, Penicillium, Phanerochaete, Genus Phlebia, genus Phycomyces, genus Piromyces, genus Pleurotus, genus Rhizopus, genus Schizophyllum, genus Streptomyces, Examples include bacteria belonging to the genera Talaromyces, Thermoascus, Thielavia, Tolypocladium, Trametes, Trichoderma, and Zygorhynchus.

Next, in the first embodiment, the "aeration/liquid culture step S1" is a step of aerating and liquid culturing the filamentous fungi of the first embodiment, and the purpose of the "aeration/liquid culture step S1" is , to efficiently produce filamentous fungal cells. In order to achieve this purpose, it is necessary to ensure the production rate of bacterial cells per unit volume, so "aeration/liquid culture" in "aeration/liquid culture step S1" is aerated agitation culture in a liquid medium. It is preferable to adopt

In addition, in the first embodiment, the "fungal cell crushing/paper-making process S2" refers to crushing and The purpose of the "fungal cell crushing/paper-making step S2" is to obtain a fungal cell fragment in which filamentous fungal cells have become fibrous and/or The objective is to obtain a paper-like bacterial cell material (a bacterial cell paper-like material). In addition, if the fungal cells of the filamentous fungi after culturing in the "aeration/liquid culture step S1" are sufficiently disaggregated and become fibrous, the "fungal cell crushing/paper-making step S2" is a "bacterial cell crushing/paper-making step S2" in which no crushing is performed. If the cells of the filamentous fungi after culturing in the "aeration/liquid culture step S1" are not sufficiently disaggregated and have not become fibrous, the "bacterial cell crushing/paper making step S2" is , a "bacterial cell crushing process" in which crushing is performed, or a "bacteria cell crushing/paper-making process" in which crushing and paper-making are performed.

In addition, in the first embodiment, the "fungal cell crushing" can be performed using a crushing device such as a refiner or a homogenizer. can be obtained. Note that the obtained crushed bacterial cells are pulp-like. On the other hand, in the first embodiment, "bacterial cell paper production" can be performed using a device such as a wire part, suction filtration, vacuum filtration, etc. ) can be obtained.

In addition, in the first embodiment, the "deacetylation treatment step S3" refers to the crushed bacterial cells obtained through the "bacterial cell crushing/paper-making step S2" of the first embodiment, as shown in FIG. This is a process of deacetylating a bacterial cell material or a bacterial cell paper-like material (a bacterial cell paper-like material), and more specifically, it is a process of deacetylating a bacterial cell material or a bacterial cell paper product (a bacterial cell paper-like material). This is a step of deacetylating chitin contained in crushed bacterial cells or paper-like bacterial cells (paper-like bacterial cells) and converting a part of the chitin into chitosan. The "deacetylation treatment process S3" can improve the tensile strength and elongation of the bacterial cell crushing product or the bacterial cell paper product (the bacterial cell paper-like material) obtained in the "microbial cell crushing/paper-making process S2". can. The degree of deacetylation of the deacetylated product of the crushed bacterial cells or the paper-like bacterial cell material is preferably 60% or more, more preferably 70% or more, and even more preferably 75% or more. , 80% is even more preferable, and 85% or more is particularly preferable.

In addition, in the first embodiment, the "plasticization treatment step S4" refers to the crushed bacterial cells obtained through the "deacetylation treatment step S3" of the first embodiment, as shown in FIG. This is a step of plasticizing a deacetylated product of a bacterial cell paper product (a bacterial paper-like material) to obtain a plasticized product of the deacetylated product, and the purpose of "plasticizing process S4" The objective is to obtain a leather-like sheet in which tensile strength and elongation are imparted to the filamentous fungal paper obtained in the "deacetylation treatment step S3". "Plasticization treatment step S4" improves the flexibility of the deacetylated product of crushed bacterial cells or cell paper products (paper-like bacterial cells) obtained through "deacetylation treatment step S3" As a result, cracks and the like can be suppressed.

The plasticizer that can be used in the "plasticization step S4" of the first embodiment is not particularly limited, and any plasticizer that can be appropriately selected by a person skilled in the art can be used. Examples thereof include oils and fats, waxes, hydrocarbons, higher fatty acids, higher alcohols, synthetic ester oils, and glycols, and one or more of these may be blended.

Examples of oils and fats include avocado oil, linseed oil, camellia oil, almond oil, sasanqua oil, macadamia nut oil, corn oil, kyonin oil, grape oil, grapeseed oil, medfoam oil, jojoba oil, olive oil, sunflower oil, Rapeseed oil, cinnamon oil, egg yolk oil, sesame oil, wheat germ oil, sasanqua oil, castor oil, safflower oil, cottonseed oil, soybean oil, peanut oil, tea seed oil, kaya oil, rice germ oil, rice bran oil, cacao butter, Coconut oil, evening primrose oil, shea butter, hydrogenated coconut oil, palm oil, palm kernel oil, Japanese oak kernel oil, hydrogenated castor oil, etc. can be mentioned, and one or more of these can be blended. .

Examples of waxes include acetic acid lanolin, liquid lanolin, sugar cane wax, reduced lanolin, and POE lanolin alcohol ether, and one or more of these can be blended.

Examples of hydrocarbons include liquid paraffin, ozokerite, squalene, paraffin, squalane, isoparaffin, octane, decane, dodecane, isododecane, hexadecane, isohexadecane, and the like. Can be blended.

Examples of higher fatty acids include lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, 12-hydroxystearic acid, undecylenic acid, tolic acid, isostearic acid, linoleic acid, linoleic acid, Icosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid, etc. can be mentioned, and one or more of these can be blended.

Examples of higher alcohols include linear alcohols such as lauryl alcohol, cetyl alcohol, stearyl alcohol, behenyl alcohol, myristyl alcohol, oleyl alcohol, and cetostearyl alcohol; monostearyl glycerin ether (batyl alcohol), 2-decyltetradecinol, and lanolin. Examples include branched chain alcohols such as alcohol, cholesterol, phytosterol, hexyldodecanol, isostearyl alcohol, and octyldodecanol; furthermore, one or more of these may be blended.

Examples of synthetic ester oils include isopropyl myristate, cetyl octoate, octyldodecyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, cetyl lactate, Myristyl lactate, lanolin acetate, isocetyl stearate, isocetyl isostearate, ethylene glycol di-2-ethylhexylate, dipentaerythritol fatty acid ester, N-alkyl glycol monoisostearate, neopentyl glycol dicaprate, diisostearyl malate, -2-heptylundecanoic acid glycerin, tri-2-ethylhexylic acid trimethylolpropane, trimethylolpropane triisostearate, tetra-2-ethylhexylic acid pentaneerythritol, tri-2-ethylhexylic acid glycerin, trimethylolpropane triisostearate, cetyl 2-Ethylhexanoate, 2-ethylhexyl palmitate, glyceryl trimyristate, tri-2-heptylundecanoic acid glyceride, castor oil fatty acid methyl ester, oleic acid oil, cetostearyl alcohol, acetoglyceride, 2-heptylundecanoate palmitate Decyl, diisobutyl adipate, N-lauroyl-L-glutamic acid-2-octyldodecyl ester, di-2-heptyl undecyl adipate, ethyl laurate, di-2-ethylhexyl sebatate, 2-hexyldecyl myristate, palmitin Examples include 2-hexyldecyl acid, 2-hexyldecyl adipate, diisopropyl sebatate, 2-ethylhexyl succinate, glyceryl trioctanoate, glyceryl triisopalmitate, isopropyl lanolin fatty acid, and hexyl laurate. One or more of these can be blended.

Examples of glycols include ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, and polypropylene glycol, and one or more of these can be blended.

Next, if the microbial cell crushing product or the microbial cell paper product (microbial cell paper-like material) obtained in the "microbial cell crushing/paper-making step S2" of the first embodiment has not been dehydrated, as shown in FIG. In the method for producing a leather-like material according to the present invention, a "dehydration step S5" is provided between the "cell crushing/paper-making step S2" and the "deacetylation step S3" of the first embodiment. The second embodiment may also be used, and as shown in FIGS. A "drying step S6" is provided between the "dehydration step S5" and "deacetylation step S3" of the second embodiment, and the third embodiment and the third embodiment of the method for producing a leather-like material according to the present invention, respectively. There may be four embodiments.

In the first embodiment, "dehydration" can be performed using a device such as a filter press, belt press, or vacuum filtration, and "drying" can be performed using a device such as hot air drying or a heat press. can. In addition, ventilation drying can be performed while elongating the hyphae.

In addition, as shown in FIG. 5, the method for producing a leather-like material according to the first embodiment is such that "deacetylation treatment step S3" and "plasticization treatment step S4" of the first embodiment are A fifth embodiment of the method for producing a leather-like material according to the present invention may include a crosslinking treatment step S7. In the "crosslinking treatment step S7", proteins, chitin, and chitosan contained in the crushed bacterial cells or the bacterial cell paper products (the bacterial paper-like material) obtained through the "deacetylation treatment step S3" are removed from tannin (tannic acid). ) or genipin can be used to further improve tensile strength and elongation.

The crosslinking agent that can be used in the "crosslinking treatment step S7" of the fifth embodiment is not particularly limited, and any crosslinking agent that can be appropriately selected by a person skilled in the art can be used. are, for example, genipin, tannins (tannic acid), other flavonoids (e.g. proanthocyanidins, catechin, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate, quercetin, chalcone, apigenin, luteolin). ), polymethoxylated flavones, quercitoi, kaempferol, myricetin, anthocyanins, resveritrol, isoflavonoids, daidzein, genistein, nobiletin, and tangeretin), bioflavonoids, riboflavin, imidoesters, epoxides (e.g., ethylene glycol diglycidyl ether), dialdehydes (e.g. glutaraldehyde), N-hydroxysuccinimide esters (e.g. 2,3-dibromopropionyl-N-hydroxysuccinimide ester, sulfo-N-hydroxysuccinimide ester, and chlorambucil-N-hydroxy succinimide ester), carbodiimide (e.g. 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride), maleimide, haloacetyl, pyridyl disulfide, hydrazide, 6-maleimidohexanoic acid active ester, disuccinimidyl suberate, Examples include bis(sulfosuccinimidyl) suberate, azide, diazirine, sulfosuccinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate, and one or two of these. The above can be blended.

Note that in the method for producing a leather-like material according to the fifth embodiment, as well as the method for producing a leather-like material according to the second embodiment, the method for producing a leather-like material in the "cell crushing/paper-making step S2" of the fifth embodiment If the resulting microbial cell crushing product or microbial cell paper product (microbial cell paper-like material) has not been dehydrated, the "bacterial cell crushing/paper-making process S2" and the "deacetylation treatment process S3" of the fifth embodiment are performed. A sixth embodiment of the method for manufacturing a leather-like material according to the present invention may be provided by including a "dehydration step S5" between the steps. Similar to the method for producing a leather-like material according to the embodiment, between the "cell crushing/paper-making process S2" and the "deacetylation process S3" of the fifth embodiment, or the "dehydration process S3" of the sixth embodiment, A seventh embodiment and an eighth embodiment of the method for producing a leather-like material according to the present invention may be provided, respectively, by providing a "drying step S6" between "step S5" and "deacetylation treatment step S3". Needless to say. The steps of the method for manufacturing a leather-like material according to the sixth embodiment, the method for manufacturing a leather-like material according to the seventh embodiment, and the method for manufacturing a leather-like material according to the eighth embodiment are not illustrated.

Note that the method for producing a leather-like material according to the present invention is not limited to the above-described embodiments, and can be modified as appropriate without impairing the characteristics of the present invention.

For example, configurations other than the embodiments and configurations described above may be employed as appropriate within a range that does not impair the characteristics of the present invention. Such configurations include, for example, a preculture step, a heating step, a washing (washing with water) step, a further dehydration step, a further drying step, and the like.

Hereinafter, the leather-like material and the manufacturing method thereof according to the present invention will be explained based on Examples. Note that the technical scope of the present invention is not limited to the embodiments shown by these Examples.

<<Example 1>> Production of leather-like material A leather-like material according to the present invention was produced. Aspergillus oryzae NBRC 4075 was used as a filamentous fungus containing chitin and/or chitosan in its cell wall. A baffled flask was inoculated with Aspergillus oryzae spores at a concentration of 1.0 x 10 ⁵ spores/mL, and precultured for 24 hours at a temperature of 30°C using a shaking incubator. In the preculture, an aqueous solution in which 24 g/L of potato dextrose was dissolved was used as a medium. The obtained culture solution was inoculated at a concentration of 3% (v/v) to the main culture solution, and inoculated using a 30L jar fermenter at 30°C, aeration rate of 1vvm, and pH 5.0. Culture was carried out under aeration and agitation for 24 hours. In the aerated agitation culture, that is, the main culture, an aqueous solution containing 10 g/L of corn steep liquor and 25 g/L of blackstrap molasses was used as a medium.

Granular microbial cells were collected from the obtained culture solution using a stainless wire mesh. An equal amount of the removed tap water was added to the collected cells, and the cells were disrupted using a homogenizer. The crushed bacterial cell slurry (dry bacterial cell content: 10 g) was suction-filtered using a filter paper with a diameter of 90 mm to obtain a bacterial cell paper product (a bacterial cell paper-like material). The obtained microbial cell paper product (microbial cell paper-like material) was air-dried at room temperature for 24 hours. FIG. 6 shows a cross section of the microbial cell paper product (microbial paper-like material). As shown in FIG. 6, it was confirmed that the hyphae contained in the mycelium paper product (mycelia paper-like material) were densely packed, and the hyphae were elongated into the voids.

Deacetylation treatment is carried out by immersing the dried bacterial cell paper product obtained above in a 30% (w/v) NaOH aqueous solution at a temperature of 100° C. for 4 hours. Did. The deacetylated microbial cell material (microbial paper-like material) was washed with water and then neutralized using acetic acid. After plasticizing the obtained deacetylated bacterial cell material (microbial paper-like material) by immersing it in a propylene glycol aqueous solution (20% (w/w)) at room temperature for 24 hours, By air drying, a sheet-like leather-like material was obtained. The obtained leather-like material had a tensile strength and elongation rate sufficient for practical use such as use in products.

Further, a cross section of the obtained leather-like material is shown in FIG. 7, and an enlarged cross section is shown in FIG. 8, respectively. As shown in FIGS. 7 and 8, the obtained leather-like material, that is, the bacterial cell paper product after deacetylation treatment and plasticization treatment, It became clear that the structure similar to that of the bacterial cell paper material before treatment was maintained, and that the resulting leather-like material, that is, the bacterial cell material after deacetylation treatment and plasticization treatment, It was revealed that the bacterial cells of Aspergillus oryzae (NBRC 4075) constituting the paper product (paper-like bacterial cell material) were arranged and stacked in a substantially oriented manner.

[Comparative Example] Production of mycelium material by a conventional method In order to compare with the leather-like material according to the present invention, a method including a step of statically culturing filamentous fungi, which is a conventional method, was used. Mycelial material was prepared. First, spores of Aspergillus oryzae (Aspergillus oryzae NBRC 4075) were inoculated at a concentration of 1.0 x 10 ⁸ spores/mL into an aqueous solution containing 48 g/L of potato dextrose, and the spores were incubated at a temperature of 30°C. Static culture was performed for 3 days. The mycelial membrane of Aspergillus oryzae (NBRC 4075) grown on the surface of the liquid medium was collected, transplanted to a freshly prepared liquid medium, and further cultured stationary at a temperature of 30° C. for 2 days. The obtained mycelial membrane was again transplanted into a freshly prepared liquid medium, and further statically cultured for 2 days at a temperature of 30°C. The obtained mycelial membrane was naturally dried at room temperature for 24 hours. A cross section of the obtained mycelial membrane is shown in FIG. As shown in FIG. 9, it became clear that the cells of Aspergillus oryzae (NBRC 4075) constituting the obtained mycelial membrane were intertwined with each other. In addition, compared with the density of Aspergillus oryzae NBRC 4075 constituting the bacterial cell paper product (microbial paper-like material) after the deacetylation treatment according to the present invention, the obtained bacterial cell density is It was revealed that the bacterial cell density of Aspergillus oryzae (NBRC 4075) constituting the mycelium membrane was small.

The obtained mycelium membrane was subjected to deacetylation treatment and plasticization treatment in the same manner as in Example 1, and then air-dried to obtain a sheet-like mycelium material. The obtained mycelial membrane was inferior in both tensile strength and elongation rate compared to the leather-like material produced in Example 1, and did not have enough tensile strength and elongation to withstand practical use such as use in products. It became clear that it had no elongation rate.

Further, a cross section of the obtained mycelium material after the deacetylation treatment and plasticization treatment is shown in FIG. 10, and an enlarged cross section is shown in FIG. 11, respectively. As shown in FIGS. 10 and 11, the mycelium material obtained after the deacetylation treatment and plasticization treatment loses its morphology due to the deacetylation treatment and plasticization treatment, and the appearance of the fungal cells disappears. The cross-sectional structure of the mycelial material obtained after the deacetylation treatment and plasticization treatment is changed compared to the cross-sectional structure of the mycelium material before the deacetylation treatment and plasticization treatment. It was also revealed that the microbial cells without orientation were densely packed, not aligned, and not stacked.

[Example 2] Study of multiple filamentous fungi Except for using Trichoderma reesei (Trichoderma reesei NBRC 31326) and Irpex lacteus (Irpex lacteus NBRC 5367) as filamentous fungi containing chitin and/or chitosan in their cell walls. By the same method as in Example 1, it was possible to obtain a leather-like material having a tensile strength and elongation rate sufficient for practical use, as in Example 1.

<<Example 3>> Examination of necessity of deacetylation treatment step A leather-like material was obtained in the same manner as in Example 1 except that deacetylation treatment was not performed. The obtained leather-like material was inferior to the leather-like material obtained in Example 1 in both tensile strength and elongation.

<<Example 4>> Study of temperature conditions and treatment time in the deacetylation treatment process Deacetylation treatment is performed by immersing in a 30% (w/v) NaOH aqueous solution at a temperature of 100°C for 4 hours. Instead, a leather-like material was obtained in the same manner as in Example 1, except that the deacetylation treatment was performed by immersion in a 30% (w/v) NaOH aqueous solution for 24 hours at room temperature. . The obtained leather-like material had comparable tensile strength and elongation as compared to the leather-like material obtained in Example 1.

<<Example 5>> Examination of necessity of plasticizing process A leather-like material was obtained in the same manner as in Example 1 except that the plasticizing process was not performed. The obtained leather-like material had comparable tensile strength but inferior elongation as compared to the leather-like material obtained in Example 1.

<<Example 6>> Examination of the crosslinking treatment step After the deacetylation treatment step of Example 1, a crosslinking treatment step was added. The deacetylated product of crushed bacterial cells or paper-like bacterial cells (paper-like bacterial cells) obtained in the deacetylation treatment step was added to an aqueous solution of condensed vegetable tannin (quebracho) (5% (w/v)). Crosslinking treatment was carried out by immersing the sample in water at room temperature for 24 hours. After washing the obtained crosslinked product with water, it was plasticized by immersing it in a propylene glycol aqueous solution (20% (w/w)) at room temperature for 24 hours, and then air-dried to obtain a leather-like material. Obtained. The obtained leather-like material had an improved tensile strength but a lower elongation rate compared to the leather-like material obtained in Example 1, but it had the same level of practicality as Example 1. It was a leather-like material with tensile strength and elongation.

《Example 7》 Study on crosslinking agent The deacetylated product of crushed bacterial cells or paper-like bacterial cells (paper-like bacterial cells) obtained in the deacetylation process was treated with an aqueous solution of condensed vegetable tannin (Quebracho). (5% (w/v)) for 24 hours at room temperature. A leather-like material was obtained in the same manner as in Example 6, except that the treated product was immersed in an aqueous genipin solution (2% (w/v)) at room temperature for 24 hours. The obtained leather-like material had improved tensile strength and comparable elongation as compared to the leather-like material obtained in Example 1.

《Example 8》Study of drying process In Example 1, instead of naturally drying the obtained bacterial cell material (bacteria paper-like material) at room temperature for 24 hours, A leather-like material was obtained in the same manner as in Example 1, except that the paper-like material was heat-dried for 1 hour at a temperature of 105°C. The obtained leather-like material had comparable tensile strength and elongation as compared to the leather-like material obtained in Example 1.

According to the leather-like material and the method for producing the same according to the present invention, the tensile strength and elongation rate are improved compared to the conventional mycelium material and the production method employing static culture or solid culture. This makes it possible to provide a leather-like mycelium material that has enough tensile strength and elongation to withstand practical use, such as for use in practical applications, and it also becomes possible to produce it in a short period of time.

Claims (7)

A leather-like material consisting of a fungal cell fragment or cell material of a filamentous fungus containing chitin and/or chitosan in its cell wall, which has been aerated and liquid-cultured, wherein the bacterial cell fragment or cell material is The leather-like material is acetylated and plasticized. A leather-like material consisting of a fungal cell fragment or cell material of a filamentous fungus containing chitin and/or chitosan in its cell wall, which has been aerated and liquid-cultured, wherein the bacterial cell fragment or cell material is The leather-like material is acetylated, crosslinked, and plasticized. (i) an aeration/liquid culture step of aerating and liquid culturing filamentous fungi containing chitin and/or chitosan in their cell walls;
(ii) a fungal cell crushing/paper-making step in which the aerated and liquid-cultured filamentous fungal cells are crushed and/or paper-made to obtain a crushed bacterial cell product or a cell-formed product;
(iii) a deacetylation treatment step of deacetylating the obtained bacterial cell fragment or bacterial cell material to obtain a deacetylated product of the bacterial cell fragment or bacterial cell material;
(iv) a plasticizing treatment step of plasticizing the obtained deacetylated product of the crushed bacterial cells or the bacterial cell extract to obtain a plasticized product of the deacetylated product;
A leather-like material produced by a method including the steps (i), (ii), (iii) and (iv) above. (i) an aeration/liquid culture step of aerating and liquid culturing filamentous fungi containing chitin and/or chitosan in their cell walls;
(ii) a fungal cell crushing/paper-making step in which the aerated and liquid-cultured filamentous fungal cells are crushed and/or paper-made to obtain a crushed bacterial cell product or a cell-formed product;
(iii) a deacetylation treatment step of deacetylating the obtained bacterial cell fragment or bacterial cell material to obtain a deacetylated product of the bacterial cell fragment or bacterial cell material;
(iv) a crosslinking treatment step of crosslinking the deacetylated product of the obtained bacterial cell crush product or bacterial cell extract to obtain a crosslinked product of the deacetylated product;
(v) a plasticizing step of plasticizing the obtained crosslinked deacetylated product to obtain a plasticized product of the crosslinked product;
A leather-like material produced by a method including the steps (i), (ii), (iii), (iv) and (v) above. A product made from the leather-like material according to at least one of claims 1 to 4 as a raw material. an aeration/liquid culture step of aerating and liquid culturing filamentous fungi containing chitin and/or chitosan in their cell walls;
A fungal cell crushing/paper-making step in which the aerated and liquid-cultured filamentous fungal cells are crushed and/or made into paper to obtain a fungal cell fragment or a fungal cell material;
a deacetylation treatment step of deacetylating the obtained bacterial cell fragments or bacterial cell material to obtain a deacetylated product of the bacterial cell fragments or bacterial cell material;
a plasticizing treatment step of plasticizing the deacetylated product of the obtained crushed bacterial cells or paper-derived bacterial cells to obtain a plasticized product of the deacetylated product. manufacturing method. an aeration/liquid culture step of aerating and liquid culturing filamentous fungi containing chitin and/or chitosan in their cell walls;
A fungal cell crushing/paper-making step in which the aerated and liquid-cultured filamentous fungal cells are crushed and/or made into paper to obtain a fungal cell fragment or a fungal cell material;
a deacetylation treatment step of deacetylating the obtained bacterial cell fragments or bacterial cell material to obtain a deacetylated product of the bacterial cell fragments or bacterial cell material;
A crosslinking treatment step of crosslinking the obtained deacetylated product of the crushed bacterial cells or the bacterial cell extract to obtain a crosslinked product of the deacetylated product;
A method for producing a leather-like material, comprising a plasticizing step of plasticizing the obtained crosslinked deacetylated product to obtain a plasticized product of the crosslinked product.

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