Method for producing a mycelium mat on leather using pH-adjusted tannic acid

Abstract

The present invention relates to a composition for crosslinking a mycelial mat-based artificial leather containing tannic acid (TA), or a method for producing a mycelial mat into leather using the same. Specifically, the method for producing a mycelial mat into leather includes a first step of inactivating the mycelial mat, a second step of permeating a polysaccharide solution into the mycelial mat, a third step of permeating a tannic acid solution into the mycelial mat permeated with the polysaccharide solution, and a fourth step of permeating a buffer into the mycelial mat permeated with the tannic acid solution.

Description

Technical Field

[0001] The present invention relates to a technology for manufacturing leather materials with improved physical strength, flexibility, and durability while using the mycelium of mushrooms, an eco-friendly material that can replace artificial leather made from animal leather and petrochemical-based synthetic polymers. Specifically, it relates to a technology for manufacturing a mycelium mat into leather using tannic acid with adjusted pH.

Background Art

[0002] Worldwide, the preference and demand for leather are increasing. However, as consumers' moral consumption perspectives also rise, the demand for alternative leather (artificial leather) without extensive killing and environmental destruction in the process of obtaining leather is increasing.

[0003] However, artificial leather has many differences in texture from natural leather, the molding process for meeting consumer perspectives becomes strict, the processing and molding processes such as dyeing and adhesion increase, the manufacturing process cost increases rapidly, the decomposition of the manufacturing using petroleum-based polymers does not go well, recycling is impossible, and various problems such as serious environmental pollution occurring throughout the entire process until it is discarded as industrial waste are faced.

[0004] In contrast, having a new material that can replace animal leather and existing artificial leather, the development of a manufacturing method for environmentally and ethically friendly leather production is an urgent reality.

[0005] Under the above circumstances, research on manufacturing leather using materials such as plant fibers, mushrooms, and silicon that can replace natural leather such as animal leather is actively being conducted.

[0006] However, the physical properties of leather produced through materials such as plant fiber, mushroom, and silicon can be adjusted by the adhering substrate, type, growth conditions, and post-treatment method. However, for industrial use, it is necessary to enhance physical strength, flexibility, and durability by using additional cross-linkers and plasticizers. Therefore, research to improve such physical properties is being actively conducted.

[0007] The mycelium of mushrooms consists of fiber threads composed of chitin-glucan complexes, proteins, and cellulose, or their complexes. The cross-linking of mycelium can occur mainly through amine groups, which are functional groups with specific positive charges of chitosan.

[0008] For the cross-linking of chitosan using covalent bonds, EDC / NHS, glyoxal, glutaraldehyde, epichlorohydrin, diisocyanate, genipin, etc. can be used.

[0009] For cross-linking methods using non-covalent bonds such as hydrogen bonds, electrostatic attractions, and other hydrophobic interactions, sodium sulphate, malic acid, tartaric acid, citric acid, succinic acid, etc. can be used.

[0010] In addition, to improve the physical properties of various chitosan-based materials, chitosan nanowhiskers, cellulose nano particles, polysaccharides such as alginic acid, biodegradable polymers, phenolic molecules, etc. can be used.

[0011] Tannin is a type of plant polyphenol molecule abundant in nature, with over 800 species existing in nature. Among them, tannic acid (TA) is composed of a structure in which five gallol groups are attached to glucose. Polyphenol molecules such as gallol groups enable various covalent and non-covalent bonds with other molecules, including hydrogen bonds, metal coordination bonds, π-cation interactions, π-π stacking, as well as nucleophilic addition reactions and imine bonds. Additionally, tannic acid can bind to chitosan through hydrogen bonds, π-cation interactions, imine bonds, and nucleophilic addition reactions, and many studies have been conducted using the tannin-chitosan (TA-chitosan) bond. However, most studies have only been carried out in fields such as films and adhesives, and no research on the leatherification of mycelium mats using tannic acid has been reported.

Summary of the Invention

Problems to be Solved by the Invention

[0012] The object of the present invention is to provide a leather material with improved physical strength, flexibility, and durability while utilizing the mycelium of mushrooms, which is an eco-friendly material that can replace artificial leather made from animal leather and petrochemical-based synthetic polymers.

Means for Solving the Problems

[0013] To achieve the above object, the present invention provides a composition for cross-linking artificial leather based on a mycelium mat containing tannic acid (TA), and the composition can be characterized in that the activity of the cross-linking reaction is improved at pH 7.5 to 9.5.

[0014] Also, the pH of the tannic acid composition may be 8 to 9.5.

[0015] Also, the pH of the tannic acid composition may be 8.5 to 9.5.

[0016] Also, the pH of the tannic acid composition may be 8.5 to 9.1.

[0017] The present invention also provides a method for manufacturing leather from a mycelium mat, including a first step of inactivating the mycelium mat, a second step of allowing a polysaccharide solution to penetrate into the mycelium mat, a third step of allowing a tannic acid solution to penetrate into the mycelium mat into which the polysaccharide solution has penetrated, and a fourth step of allowing a buffer to penetrate into the mycelium mat into which the tannic acid solution has penetrated. In the fourth step, the pH of the tannic acid composition may be 7.5 to 9.5.

[0018] The tannic acid solution may contain any one or more solvents selected from ethanol at a concentration of 70 to 95% (v / v) and acetone at a concentration of 70 to 95% (v / v).

[0019] The buffer may be any one or more selected from the group consisting of hydrogen chloride (HCl), potassium hydroxide (KOH), sodium hydroxide (NaOH), sodium bicarbonate (NaHCO3), bis-tris propane buffer, BES buffer (N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid), MOPS buffer (3-(N-morpholino)propanesulfonic acid), HEPES buffer (2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid), TES buffer (N-Tris(hydroxymethyl)methyl-2-aminoethanesulfonicd acid), MOBS buffer (4-(N-Morpholino)butanesulfonic acid), TRIS buffer (Tris(hydroxymethyl)aminomethane), DIPSO buffer (3-(N,N-Bis[2-hydroxyethyl]amino)-2-hydroxypropanesulfonic acid), PBS buffer (Phosphate-buffered saline), and glycine.

[0020] In addition, the present invention provides a method for manufacturing a mycelium mat into leather, which comprises any one selected from the group consisting of chitosan, k-carrageenan, I-carrageenan, L-carrageenan, guar gum, xanthan, gum arabic, pectin, peptone, konjac, dextran, heparin, fucoidan, and alginic acid.

[0021] In addition, the present invention provides a method for manufacturing a mycelium mat into leather, which further comprises a fifth step of plasticizing the cross-linked mycelium mat with a plasticizer solution.

[0022] The plasticizer solution may contain any one or more selected from the group consisting of ethylene glycol, ethylene glycerol, glycerol, polyethylene glycol (PEG), polypropylene glycol (PPG), polysorbate, cyclodextrin, lavender oil, castor oil, and cinnamaldehyde.

Advantages of the Invention

[0023] Since the leather material obtained by the manufacturing method of the present invention utilizes the mycelium of mushrooms, it is environmentally friendly and has improved physical properties such as tensile strength.

Brief Description of the Drawings

[0024]

Figure 1

Figure 2

Mode for Carrying Out the Invention

[0025] Hereinafter, the present invention will be described in detail with reference to Examples and Experimental Examples.

[0026] However, the following Examples and Experimental Examples are illustrative of the present invention, and the content of the present invention is not limited by the following Examples and Experimental Examples.

[0027] Production Example: Extraction of Mycelium Mat (mat) <Original Fungus Cultivation> PDA (potato dextrose agar) was dispensed into 90 mm Petri dishes and solidified for 5 minutes, after which a PDA medium was prepared.

[0028] Sections of mycelium of woody fungi (Ganoderma sp., Fomitella Sp. or Inonotus sp.) were cut out from a sterile zone, transplanted onto the PDA medium, and cultured in an incubator at 28 °C for 7 days.

[0029] Sections of the strain cultured on the PDA medium (scaffold mass transfer) were cut into 5 pieces so that the size became 10 mm 2 and inoculated into 500 mL of YPDB (potato dextrose broth containing 0.5% yeast extract) liquid medium, and the original fungus was cultured at 25 °C for 7 days while stirring at 180 rpm.

[0030] <Liquid Culture> At 25 °C, 40 g of dextrose, 20 g of yeast extract, and 20 g of guar-gum were mixed with 920 mL of distilled water to prepare a nutrient component composition.

[0031] After the nutrient components, 0.5 g of magnesium sulfate (MgSO4), 0.5 g of calcium carbonate (CaCO3), 0.5 g of potassium phosphate (KH2PO4), and 0.5 g of calcium chloride (CaCl2) were dissolved in 998 mL of distilled water at 25 °C to prepare an inorganic salt composition.

[0032] The composition and the inorganic salt composition were mixed and stirred at 200 rpm for 10 minutes at 25 °C through a stirring device (DAIHAN scientific, HT-120DX) to prepare 2 L of a medium composition.

[0033] The medium composition was sterilized at 132 °C with a steam pressure of 5 kgf / cm2 for 25 minutes using an autoclave, and the sterilized medium composition was cooled to 25 °C to prepare a semi-liquid medium, which was filled to 1000 mL in a 1 / 2 vat.

[0034] In the primary bacterial culture step, 200 mL of the composition containing the primary bacteria cultured at 25 °C for 7 days was inoculated into 1000 mL of the semi-liquid medium, and then covered with a lid equipped with a filter and a vent, and cultured in the dark for 4 weeks at 28 °C and 90% humidity to extract 300 g of living mycelium mats.

[0035] Example 1: Manufacture of alternative leather using mycelium mats - pH 8.5 condition The mycelium mats extracted in the production example were immersed in 400 mL of 30% hydrogen peroxide at 60 °C and subjected to ultrasonic treatment at 35 kHz for 2 hours at 60 °C.

[0036] 8 g of chitosan, 8 g of adipic acid, and distilled water were mixed at 25 °C to produce 400 mL of a 2% chitosan solution, and then the ultrasonically treated mycelium mats were immersed in the chitosan solution at 25 °C for 1 day.

[0037] 6.8 g of tannic acid and 400 mL of a 70% (v / v) ethanol aqueous solution were mixed at 25 °C to produce an ethanolic tannic acid solution (10 mM, 400 mL).

[0038] Subsequently, the mycelium mat immersed in the chitosan solution was immersed in the ethanolic tannic acid solution (10 mM, 400 mL) for 2 hours.

[0039] After the 2-hour immersion treatment, the mycelium mat immersed in the ethanolic tannic acid solution at 25°C was immersed in a Tris buffer solution (10 mM, 400 mL) at pH 8.5 for 4 hours.

[0040] 60 mL of polyethylene glycol (PEG) was mixed with 340 mL of distilled water at 25°C to produce 400 mL of a 15% polyethylene glycol solution. Then, the mycelium mat immersed in the tannic acid solution was immersed in the prepared 15% polyethylene glycol solution (400 mL) and stirred at 25°C for 6 hours at 200 rpm.

[0041] The mycelium mat immersed in the polyethylene glycol (PEG) solution was dried at 40°C for 24 hours or more to remove moisture, and then heat-pressed at 90°C under a pressure of 98 MPa for 20 seconds using a heat-pressing device (custom village, CDH-4050) to produce a mycelium leather with a width of 27.5 cm, a length of 21.5 cm, and a thickness of 0.8 cm.

[0042] The prepared mycelium leather was immersed in 100 mL of a primer solution (HyuJeong chemical, MR-100 Clear solution) composed of a polyurethane-based polymer and acetone at 25°C for 1 hour.

[0043] The mycelium leather immersed in the primer solution was washed with an excess of 100% acetone solution for 10 minutes to remove unreacted primer, and the mycelium leather from which the primer had been removed was dried at 60°C for 5 minutes.

[0044] A coating solution was prepared by mixing an aqueous polyurethane dispersion (HyuJeong chemical, PUD-A) and an aqueous colorant (Wooshin pigment, AQUALOR (registered trademark)) at a ratio of 9:1.

[0045] After the above dyeing and drying were completed, the mycelium leather was coated with the coating liquid five times at 120 cc / min.

[0046] The mycelium leather coated with the coating liquid was dried at 100 °C for 5 minutes.

[0047] The dried mycelium leather was processed with an embossing pattern at a pressure of 196 Pa for 20 seconds using an embossing pattern press device (manufactured by DR-tech, product DR1003) heated to 110 °C.

[0048] A hot melt adhesive film (manufactured by JCC KOREA, F604L) with a width of 27.5 cm, a length of 21.5 cm, and a thickness of 40 μm was bonded to the surface of the embossing pattern-processed mycelium leather. After covering the fiber reinforcing material (UMOFIL (registered trademark)), the embossing pattern-processed mycelium leather and the fiber reinforcing material were laminated at 120 °C for 20 seconds using a heat fusion device (Custom Village, CDH-4050) to produce a mycelium leather product with a width of 27.5 cm, a length of 21.5 cm, and a thickness of 0.12 cm.

[0049] The above experimental process was repeated to prepare five mycelium leather samples with a width of 27.5 cm, a length of 21.5 cm, and a thickness of 0.12 cm.

[0050] Example 2: Production of alternative leather using mycelium mat - pH 9 condition After the 2-hour immersion treatment in Example 1 was completed, the process of immersing the mycelium mat immersed in the ethanolic tannic acid solution at 25 °C in a tris buffer solution (10 mM, 400 mL) with a pH of 8.5 for 4 hours was replaced with the process of immersing the mycelium mat immersed in the ethanolic tannic acid solution at 25 °C in a tris buffer solution (10 mM, 400 mL) with a pH of 9 for 4 hours. All other steps were performed in the same manner, and five mycelium leather samples with a width of 27.5 cm, a length of 21.5 cm, and a thickness of 0.12 cm were prepared.

[0051] Comparative Example 1: Production of alternative leather using mycelium mat - pH 5.7 condition After the 2-hour immersion treatment in Example 1, without performing only the process of immersing the mycelium mat immersed in the ethanolic tannic acid solution at 25°C in a tris buffer solution (10 mM, 400 mL) at pH 8.5 for 4 hours, while maintaining the pH of the tannic acid solution at 5.7, all the steps were carried out in the same manner, and 5 mycelium leather samples with a width of 25 cm, a length of 20 cm, and a thickness of 40 μm were prepared.

[0052] Comparative Example 2: Manufacture of alternative leather using mycelium mat - pH 7 condition After the 2-hour immersion treatment in Example 1, the process of immersing the mycelium mat immersed in the ethanolic tannic acid solution at 25°C in a tris buffer solution (10 mM, 400 mL) at pH 8.5 for 4 hours was replaced with the process of immersing the mycelium mat immersed in the ethanolic tannic acid solution at 25°C in a tris buffer solution (10 mM, 400 mL) at pH 7 for 4 hours. All other steps were carried out in the same manner, and 5 mycelium leather samples with a width of 27.5 cm, a length of 21.5 cm, and a thickness of 0.12 cm were prepared.

[0053] Comparative Example 3: Manufacture of alternative leather using mycelium mat - pH 10 condition After the 2-hour immersion treatment in Example 1, the process of immersing the mycelium mat immersed in the ethanolic tannic acid solution at 25°C in a tris buffer solution (10 mM, 400 mL) at pH 8.5 for 4 hours was replaced with the process of immersing the mycelium mat immersed in the ethanolic tannic acid solution at 25°C in a tris buffer solution (10 mM, 400 mL) at pH 10 for 4 hours. All other steps were carried out in the same manner, and 5 mycelium leather samples with a width of 27.5 cm, a length of 21.5 cm, and a thickness of 0.12 cm were prepared.

[0054] Experimental Example: Tensile strength measurement To confirm the improvement in the tensile strength of the mycelium mat immersed in the tannic acid solution and with the pH adjusted, the tensile strengths of the mycelium leather samples produced in Example 1 and Example 2, Comparative Example 1, Comparative Example 2, and Comparative Example 3 were measured.

[0055] The tensile strength was measured using a tensile testing machine (QMESYS). The mycelium leather samples of Example 1, Example 2, Comparative Example 1, Comparative Example 2, and Comparative Example 3 were placed in the tensile testing machine and pulled at 100 mm / min. After obtaining the maximum tensile strength (N) at the break of the leather sample, the average tensile strength values of five samples each were determined for Example 1, Example 2, Comparative Example 1, Comparative Example 2, and Comparative Example 3. The results are shown in Table 1 and Figure 2 below.

[0056]

Table 1

[0057] (Mode for Carrying Out the Invention) Hereinafter, the present invention will be described in detail.

[0058] The present invention provides a composition for crosslinking artificial leather based on a mycelium mat containing tannic acid (TA), and the composition can be characterized in that the activity of the crosslinking reaction is improved at pH 7.5 to 9.5.

[0059] As consumers' moral consumption perspectives have both increased, the demand for alternative leather (artificial leather) without extensive killing and environmental destruction in the process of obtaining leather has been increasing.

[0060] However, since the texture of artificial leather is significantly different from that of natural leather, the molding process has become more stringent, the processing and molding processes by dyeing and adhesion have increased, and the manufacturing process cost has increased rapidly.

[0061] At the same time, various problems are faced, such as serious environmental pollution occurring throughout the entire process until the decomposition of the production using petroleum-based polymers fails and it is discarded as industrial waste without being recyclable.

[0062] The inventors have completed the present invention for a mycelium mat-based leather material that is environmentally friendly and improves physical properties such as tensile strength, replacing natural leather such as animal leather.

[0063] Defining the term "tannic acid (TA)" used in the present invention, the chemical formula is C76H52O46, the molecular weight is 1701.2 g / mol, the CAS number is 1401-55-4, and it can mean a polyphenolic molecule having glucose in the center and functionalized with five gallol groups at the ends.

[0064] As described above, tannic acid having a gallol group can form covalent and non-covalent bonds such as hydrogen bonds, metal coordination bonds, π-cation interactions, π-π stacking, nucleophilic addition reactions, and imine bonds with various other molecules. Also, the surface of various materials can be modified by oxidation at a pH near the pKa, and secondary surface modification is also possible.

[0065] The "tannic acid composition" in the present invention can mean a composition in which a tannic acid solution and a buffer are mixed, which may have the same meaning as the composition for artificial cross-linking in this specification. By adjusting the pH of the tannic acid composition, the activity of the cross-linking reaction of the mycelium mat can be improved.

[0066] The pH of the tannic acid composition may be 7.5 to 9.5, preferably 8 to 9.5, more preferably 8.5 to 9.5, and even more preferably 8.5 to 9.1, which can be adjusted to a solution by the action of basic solvents or buffers such as hydrogen chloride (HCl), potassium hydroxide (KOH), sodium hydroxide (NaOH), sodium bicarbonate (NaHCO3), bis-tris propane buffer, BES buffer (N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid), MOPS buffer (3-(N-morpholino)propanesulfonic acid), HEPES buffer (2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid), TES buffer (N-Tris(hydroxymethyl)methyl-2-aminoethanesulfonicd acid), MOBS buffer (4-(N-Morpholino)butanesulfonic acid), TRIS buffer (Tris(hydroxymethyl)aminomethane), DIPSO buffer (3-(N,N-Bis[2-hydroxyethyl]amino)-2-hydroxypropanesulfonic acid), PBS buffer (Phosphate-buffered saline), and glycine.

[0067] The gallol group of the tannic acid undergoes oxidation under weakly basic conditions to form quinones. The quinones of the oxidized gallol groups can react with the nucleophilic functional groups (amine groups, thiol groups) contained in chitosan and the mycelial mat to cause a nucleophilic addition reaction or to form covalent bonds such as imine bond formation through a dehydration condensation reaction.

[0068] The pH of the tannic acid composition may be 7.5 to 9.5, preferably 8 to 9.5, more preferably 8.5 to 9.5, and even more preferably 8.5 to 9.1. However, when the pH is less than 7.5, the formation of semiquinone due to the oxidation of the gallol group of tannic acid decreases, and the activity of the cross-linking reaction of the mycelium may not be sufficient. When the pH exceeds 9.5, the semiquinone form cannot be maintained, and problems such as quinone-induced peroxidation or hydrolysis of tannic acid may occur, resulting in the cross-linking reaction not taking place.

[0069] As described above, by optimizing the cross-linking reaction with the pH of the tannic acid composition being 7.5 to 9.5, it was confirmed that when the mycelium mat was made into leather, the tensile strength was significantly improved within the above range (experimental example).

[0070] The present invention provides a composition for cross-linking artificial leather based on a mycelium mat, wherein the tannic acid is 1 to 20 mM with respect to the total volume of the tannic acid solution.

[0071] The present invention provides a method for manufacturing a mycelium mat into leather, which includes a first step of inactivating the mycelium mat, a second step of infiltrating a polysaccharide solution into the mycelium mat, a third step of infiltrating a tannic acid solution into the mycelium mat infiltrated with the polysaccharide solution, and a fourth step of infiltrating a buffer into the mycelium mat infiltrated with the tannic acid solution. In the fourth step, the pH of the tannic acid composition may be 7.5 to 9.5.

[0072] The term "inactivation of the mycelium mat" used in the present invention may mean a decrease or suppression of the biological activity of the mycelium.

[0073] For the mycelial mat culture of the present invention, mycelial sections isolated from woody mushrooms such as Ganoderma sp., Fomitella Sp. or Inonotus sp. can be used. Specifically, mycelial sections isolated from the mycelia of Inonotus obliquus, Phellinus linteus or Ganoderma lucidum can be used, but are not limited thereto. Known methods that utilize a solid or semi-liquid medium can be used for culturing the mycelia.

[0074] The present invention can include a first step process of inactivating the mycelial mat, and methods such as sterilization, ultrasonic treatment, chemical treatment, etc. can be used herein.

[0075] The sterilization method is a method that utilizes an autoclave, and can be a method of sterilizing living mycelia under temperature and pressure conditions higher than the maximum limit temperature of 119°C and 1.2 atmospheres at which organisms can live medically. Specifically, the mycelial mat can be inactivated by sterilization at 121°C and 1.5 atmospheres for 30 minutes.

[0076] The inactivation of the mycelial mat using the ultrasonic wave can be carried out by putting living mycelia into distilled water in a frequency range of 35 - 50 kHz for 2 hours.

[0077] The chemical treatment method may be a method of inactivating the mycelial mat using hydrogen peroxide (H2O2), sodium hypochlorite (NaClO), sodium hydroxide (NaOH), etc.

[0078] The hydrogen peroxide solution is a substance that can react with enzymes to generate active oxygen or oxygen radicals and dissolve cell walls and cell membranes, and a 3% hydrogen peroxide solution is often used for medical purposes.

[0079] In the treatment method using the hydrogen peroxide solution in the present invention, the concentration of hydrogen peroxide may be 5 to 30% with respect to the total volume of the hydrogen peroxide solution, and the mycelial mat can be immersed in the solution under the temperature condition of 25 to 60 ° C for 1 minute to 2 hours. At this time, if the concentration of hydrogen peroxide is 10 to 30% with respect to the total solution volume, ultrasonic treatment needs to be performed for 1 hour or more before the hydrogen peroxide solution treatment.

[0080] The sodium hypochlorite is known as the main component of Rack's, and can be diluted for sterilization purposes according to the application.

[0081] In the treatment method using the sodium hypochlorite solution in the present invention, the concentration of sodium hypochlorite may be 0 to 30% with respect to the total solution volume, and the mycelial mat can be immersed in the solution under the temperature condition of 25 to 60 ° C for 1 minute to 2 hours. At this time, in order to inactivate the mycelium, it is preferable to perform ultrasonic treatment for 1 hour or more and immerse it using a solution containing 5% or more of sodium hypochlorite, or immerse it in a solution of 5% or more of sodium hypochlorite for 2 hours or more without ultrasonic treatment.

[0082] In the present invention, it may include a second step of infiltrating the polysaccharide solution into the mycelial mat, and the polysaccharide contained in the polysaccharide solution may be any selected from the group consisting of chitosan, k-carrageenan, I-carrageenan, L-carrageenan, Guar gum, xanthan, Gum Arabic, pectin, peptone, konjac, dextran, heparin, fucoidan and Alginic acid.

[0083] In the present invention, it is possible to penetrate chitosan and adipic acid into the inactivated mycelium mat. However, simply after penetrating chitosan and adipic acid and then drying at a low temperature and performing heat crimping may not be suitable for cross-linking through amide bonds, which are possible bonds between the amine group of chitosan and the carboxyl group of adipic acid.

[0084] Therefore, the present invention may include a third step of penetrating a tannic acid solution into the mycelium mat penetrated with the polysaccharide solution.

[0085] The gallol group of the tannic acid undergoes oxidation under weakly basic conditions to form quinone. The quinone of the oxidized gallol group reacts with the nucleophilic functional groups (amine group, thiol group) contained in chitosan and the mycelium mat to cause a nucleophilic addition reaction or to form a covalent bond such as an imine bond through a dehydration condensation reaction.

[0086] The present invention may include a fourth step of penetrating a buffer into the mycelium mat penetrated with the tannic acid solution. In the fourth step, the tannic acid solution can be mixed with the buffer to form a tannic acid composition.

[0087] The pH of the tannic acid composition may be 7.5 to 9.5, preferably 8 to 9.5, more preferably 8.5 to 9.5, and even more preferably 8.5 to 9.1. However, when the pH is less than 7.5, the formation of semiquinone due to the oxidation of the gallol group of tannic acid decreases, and the cross-linking treatment of the mycelium may not be sufficient. When the pH exceeds 9.5, the semiquinone form cannot be maintained, and problems such as peroxidation with quinone or hydrolysis of tannic acid may occur, resulting in no cross-linking reaction.

[0088] The pH of the tannic acid composition is 7.5 - 9.4, 7.5 - 9.3, 7.5 - 9.2, 7.5 - 9.1, 7.5 - 9.0, 7.5 - 8.9, 7.5 - 8.8, 7.5 - 8.7, 7.5 - 8.6, 7.5 - 8.5, 7.5 - 8.4, 7.5 - 8.3, 7.5 - 8.2, 7.5 - 8.1, 7.5 - 8.0, 7.5 - 7.9, 7.5 - 7.8, 7.5 - 7.7, 7.5 - 7.6, 7.6 - 9.4, 7.6 - 9.3, 7.6 - 9.2, 7.6 - 9.1, 7.6 - 9.0, 7.6 - 8.9, 7.6 - 8.8, 7.6 - 8.7, 7.6 - 8.6, 7.6 - 8.5, 7.6 - 8.4, 7.6 - 8.3, 7.6 - 8.2, 7.6 - 8.1, 7.6 - 8.0, 7.6 - 7.9, 7.6 - 7.8, 7.6 - 7.7, 7.7 - 9.4, 7.7 - 9.3, 7.7 - 9.2, 7.7 - 9.1, 7.7 - 9.0, 7.7 - 8.9, 7.7 - 8.8, 7.7 - 8.7, 7.7 - 8.6, 7.7 - 8.5, 7.7 - 8.4, 7.7 - 8.3, 7.7 - 8.2, 7.7 - 8.1, 7.7 - 8.0, 7.7 - 7.9, 7.7 - 7.8, 7.8 - 9.4, 7.8 - 9.3, 7.8 - 9.2, 7.8 - 9.1, 7.8 - 9.0, 7.8 - 8.9, 7.8 - 8.8, 7.8 - 8.7, 7.8 - 8.6, 7.8 - 8.5, 7.8 - 8.4, 7.8 - 8.3, 7.8 - 8.2, 7.8 - 8.1, 7.8 - 8.0, 7.8 - 7.9, 7.9 - 9.4, 7.9 - 9.3, 7.9 - 9.2, 7.9 - 9.1, 7.9 - 9.0, 7.9 - 8.9, 7.9 - 8.8, 7.9 - 8.7, 7.9 - 8.6, 7.9 - 8.5, 7.9 - 8.4, 7.9 - 8.3, 7.9 - 8.2, 7.9 - 8.1, 7.9 - 8.0, 8.0 - 9.4, 8.0 - 9.3, 8.0 - 9.2, 8.0 - 9.1, 8.0 - 9.0, 8.0 - 8.9, 8.0 - 8.8, 8.0 - 8.7, 8.0 - 8.6, 8.0 - 8.5, 8.0 - 8.4, 8.0 - 8.3, 8.0 - 8.2, 8.0 - 8.1, 8.1 - 9.4, 8.1 - 9.3, 8.1 - 9.2, 8.1 - 9.1, 8.1 - 9.0, 8.1 - 8.9, 8.1 - 8.8, 8.1 - 8.7, 8.1 - 8.6, 8.1 - 8.5, 8.1 - 8.4, 8.1 - 8.3, 8.1 - 8.2, 8.2 - 9.4, 8.2 - 9.3, 8.2 - 9.2, 8.2 - 9.1, 8.2 - 9.0, 8.2 - 8.9, 8.2 - 8.8, 8.2 - 8.7, 8.2 - 8.6, 8.2 - 8.5, 8.2 - 8.4, 8.They can be, for example, 2 to 8.3, 8.3 to 9.4, 8.3 to 9.3, 8.3 to 9.2, 8.3 to 9.1, 8.3 to 9.0, 8.3 to 8.9, 8.3 to 8.8, 8.3 to 8.7, 8.3 to 8.6, 8.3 to 8.5, 8.3 to 8.4, 8.4 to 9.4, 8.4 to 9.3, 8.4 to 9.2, 8.4 to 9.1, 8.4 to 9.0, 8.4 to 8.9, 8.4 to 8.8, 8.4 to 8.7, 8.4 to 8.6, 8.5 to 9.4, 8.5 to 9.3, 8.5 to 9.2, 8.5 to 9.1, 8.5 to 9.0, 8.5 to 8.9, 8.5 to 8.8, 8.5 to 8.7, 8.5 to 8.6, 8.6 to 9.4, 8.6 to 9.3, 8.6 to 9.2, 8.6 to 9.1, 8.6 to 9.0, 8.6 to 8.9, 8.6 to 8.8, 8.6 to 8.7, 8.7 to 9.4, 8.7 to 9.3, 8.7 to 9.2, 8.7 to 9.1, 8.7 to 9.0, 8.7 to 8.9, 8.7 to 8.8, 8.8 to 9.4, 8.8 to 9.3, 8.8 to 9.2, 8.8 to 9.1, 8.8 to 9.0, 8.8 to 8.9, 8.9 to 9.4, 8.9 to 9.3, 8.9 to 9.2, 8.9 to 9.1, 8.9 to 9.0, 9.0 to 9.4, 9.0 to 9.3, 9.0 to 9.2, 9.0 to 9.1, etc.

[0089] When the mycelial mat was manufactured into leather by adjusting the pH of the tannic acid composition in the range of 7.5 to 9.5 to optimize the activity of the crosslinking reaction as described above, it was confirmed that the tensile strength was significantly improved within the above range (Examples 1, 2, and Experimental Examples).

[0090] The tannic acid solution may contain any one or more solvents selected from ethanol at a concentration of 70 to 95% (v / v) and acetone at a concentration of 70 to 95% (v / v).

[0091] Ethanol or acetone contained in the tannic acid solution can dissolve tannic acid, but polysaccharides contained in the polysaccharide solution described later cannot be dissolved. Therefore, when the mycelial mat impregnated with chitosan is immersed in the tannic acid solution dissolved in ethanol, only tannic acid penetrates into the mycelial mat, and there is an effect of maximizing crosslinking.

[0092] The concentration of ethanol or acetone contained in the tannic acid solution can be 70 to 95% (v / v). However, when it is less than 70%, there may be a problem that the polysaccharides previously penetrated into the mycelium dissolve and come out, or the tannic acid reacts and loses its activity before entering the mycelium mat. When it exceeds 95%, the tannic acid may not dissolve.

[0093] The solvent contained in the tannic acid solution can mean an aqueous ethanol solution with a concentration of 70 to 95% (v / v), an aqueous acetone solution with a concentration of 70 to 95% (v / v), or a mixture thereof. However, other solvents that can dissolve tannin in powder form in the tannic acid solution and increase its activity may also be usable.

[0094] The buffer may be any one or more selected from the group consisting of hydrogen chloride (HCl), potassium hydroxide (KOH), sodium hydroxide (NaOH), sodium bicarbonate (NaHCO3), bis-tris propane buffer, BES buffer (N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid), MOPS buffer (3-(N-morpholino)propanesulfonic acid), HEPES buffer (2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid), TES buffer (N-Tris(hydroxymethyl)methyl-2-aminoethanesulfonicd acid), MOBS buffer (4-(N-Morpholino)butanesulfonic acid), TRIS buffer (Tris(hydroxymethyl)aminomethane), DIPSO buffer (3-(N,N-Bis[2-hydroxyethyl]amino)-2-hydroxypropanesulfonic acid), PBS buffer (Phosphate-buffered saline), and glycine.

[0095] The buffer adjusts the pH of the tannic acid composition to weakly basic, and can form quinones by the oxidation of gallol groups contained in the tannic acid. The quinones of the oxidized gallol groups react with nucleophilic functional groups (amine groups, thiol groups) contained in chitosan and the mycelial mat, and a nucleophilic addition reaction may occur, or covalent bonds such as imine bond formation can be formed by a dehydration condensation reaction.

[0096] Specifically, the pH of the tannic acid composition may be 7.5 to 9.5. When the pH is less than 7.5, the formation of semiquinones by the oxidation of the gallol groups of tannic acid decreases, and the cross-linking treatment of the mycelium may not be sufficient. When the pH exceeds 9.5, the semiquinone form cannot be maintained, and problems such as peroxidation with quinones or hydrolysis of tannic acid may occur, resulting in no cross-linking reaction.

[0097] As described above, by optimizing the cross-linking reaction by adjusting the pH of the tannic acid composition in the range of 7.5 to 9.5, when the mycelial mat was manufactured into leather, it was confirmed that the tensile strength was significantly improved in the above range (experimental example).

[0098] In the present invention, a step of adding a cross-linking agent to strengthen the cross-linking reaction of the mycelial mat can be included, and this can be included in the processes before and after the fourth step in which the pH of the tannic acid composition formed by adding a buffer is adjusted to 7.5 to 9.5.

[0099] The crosslinking agents that may be included herein are one or more selected from N-ethylcarbodiimide hydrochloride (EDC), EDC / NHS, carbodiimidazole, N,N'-dicyclohexylcarbodiimide, disuccinimidyl carbonate, disuccinimidyl suberate, glyoxal, glutaraldehyde, epochlorohydrin, genipin, or any one or more of monomolecular or polymer molecules containing functional groups such as isocyanate, isothiocyanate, acrylamide, NHS-ester, sulfonyl chloride, aldehyde, imidoester, diazoalkane, diazoacetyl, epoxide, and alkyl halide.

[0100] The present invention further provides a method for producing a mycelium mat into leather, which further includes a fifth step of plasticizing the crosslinked mycelium mat with a plasticizer solution.

[0101] The term "plasticizer" used in the present invention is an additive that reduces the viscosity or plasticity of a substance and can mean a substance added to change physical properties such as the softening point, glass transition point, and thermal and mechanical properties of a polymer, and may be a substance commonly used in the production of plastics.

[0102] The plasticizer solution can contain any one or more selected from the group consisting of ethylene glycol, ethylene glycerol, glycerol, polyethylene glycol (PEG), polypropylene glycol (PPG), polysorbate, cyclodextrin, lavender oil, castor oil, and cinnamaldehyde.

[0103] In a specific embodiment of the present invention, a mycelium mat-based leather sample was produced using a composition for cross-linking artificial leather containing pH-adjusted tannic acid, and the tensile strength of the produced leather was measured (Experimental Example).

Industrial Applicability

[0104] The present invention relates to a composition for cross-linking artificial leather based on a mycelium mat containing tannic acid (TA) or a method for producing a mycelium mat using the same into leather. The mycelium mat produced by the production method can replace artificial leather using animal leather and petrochemical-based synthetic polymers with the mycelium of mushrooms, which is an eco-friendly material, and can provide a leather material with improved physical strength, flexibility, and durability. Therefore, it has industrial applicability.

Claims

1. A composition for crosslinking a mycelium mat-based artificial leather, comprising tannic acid (TA), characterized in that the activity of the crosslinking reaction is improved at pH 7.5 to 9.

5. The composition for crosslinking a mycelium mat-based artificial leather, characterized in that the pH is 7.5 to 9.

5.

2. The composition for crosslinking a mycelium mat-based artificial leather according to Claim 1, characterized in that the pH is 8 to 9.

5.

3. The composition for crosslinking a mycelium mat-based artificial leather according to Claim 1, characterized in that the pH is 8.5 to 9.

5.

4. The composition for crosslinking a mycelium mat-based artificial leather according to Claim 1, characterized in that the pH is 8.5 to 9.

1.

5. A method for manufacturing leather from a mycelium mat, comprising: a first step of inactivating the mycelium mat; a second step of infiltrating the mycelium mat with a polysaccharide solution; a third step of infiltrating the mycelium mat infiltrated with the polysaccharide solution with a tannic acid solution; and a fourth step of infiltrating the mycelium mat infiltrated with the tannic acid solution with a buffer, wherein the pH of the tannic acid composition in the fourth step is 7.5 to 9.

5.

6. The method for manufacturing leather from a mycelium mat according to Claim 5, wherein the polysaccharide solution contains any one or more selected from the group consisting of chitosan, k-carrageenan, I-carrageenan, L-carrageenan, guar gum, xanthan, gum arabic, pectin, peptone, konjac, dextran, heparin, and fucoidan.

7. The method for manufacturing leather from a mycelium mat according to Claim 5, wherein the tannic acid solution contains any one or more solvents selected from ethanol at a concentration of 70 to 95% (v / v) and acetone at a concentration of 70 to 95% (v / v).

8. ​ ​ ​ The buffer is any one or more selected from the group consisting of hydrogen chloride (HCl), potassium hydroxide (KOH), sodium hydroxide (NaOH), sodium bicarbonate (NaHCO₃), bis-tris propane buffer, BES buffer (N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid), MOPS buffer (3-(N-morpholino)propanesulfonic acid), HEPES buffer (2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid), TES buffer (N-Tris(hydroxymethyl)methyl-2-aminoethanesulfonicd acid), MOBS buffer (4-(N-Morpholino)butanesulfonic acid), TRIS buffer (Tris(hydroxymethyl)aminomethane), DIPSO buffer (3-(N,N-Bis[2-hydroxyethyl]amino)-2-hydroxypropanesulfonic acid), PBS buffer (Phosphate-buffered saline), and glycine (glycine). The method for producing a mycelial mat according to claim 5, which is any one or more selected from the group consisting of

9. The method for producing a mycelial mat into leather according to claim 5, further comprising a fifth step of plasticizing the mycelial mat with a plasticizer solution after the fourth step.

10. The plasticizer solution contains any one or more selected from the group consisting of ethylene glycol (ethylene glycol), ethylene glycerol (ethylene glycerol), glycerol (glycerol), polyethylene glycol (polyethylene glycerol, PEG), polypropylene glycol (polypropylene glycol, PPG), polysorbate, cyclodextrin, lavender oil, castor oil, and cinnamaldehyde. The method for producing a mycelial mat into leather according to claim 9, characterized in that it contains

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