Method of manufacturing concave-convex pattern structure

Abstract

To provide a technology for manufacturing an uneven pattern structure capable of imitating the structure and softness of the surface of a biological tissue.SOLUTION: Forming a film of a hydro-gel B having a modulus of rigidity in swelling of 0. 10kPa or more and 12. 00kPa or less on the base of the hydro-gel A.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for producing a concave-convex pattern structure, and a concave-convex pattern structure obtained by the production method. [Background technology]

[0002] The surface of biological tissue often has a complex topographical pattern. For example, the surface of the brain of some organisms has a large ratio of surface area to volume of the cerebral cortex, resulting in a complex wrinkled structure. Reproducing the topographical pattern of biological tissue surfaces can be used to elucidate the mechanism by which the topographical pattern is formed. It may also be useful for elucidating the pathology and developing treatment strategies for diseases that exhibit abnormal topographical patterns (e.g., lissencephaly, schizencephaly, etc. in the brain).

[0003] Non-Patent Document 1 attempts to mimic the brain surface structure using a polydimethylsiloxane gel. However, the gel used in Non-Patent Document 1 is much harder than biological tissue. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Proc Natl Acad Sci US A. 2014 Sep 2;111(35):12667-72. doi: 10.1073 / pnas.1406015111. Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a technique for manufacturing a concave-convex pattern structure that can mimic the structure and softness of the surface of biological tissue. [Means for solving the problem]

[0006] The present inventors have conducted extensive research in light of the above-mentioned problems and have found that the above-mentioned problems can be solved by a method for producing a concave-convex pattern structure, which includes forming a film of hydrogel B, the film having a modulus of rigidity when swollen of 0.10 kPa or more and 12.00 kPa or less, on a substrate of hydrogel A. Based on this finding, the present inventors have conducted further research and have completed the present invention. That is, the present invention encompasses the following aspects.

[0007] Item 1. A method for producing a concave-convex pattern structure, comprising forming a film of hydrogel B having a modulus of rigidity when swollen of 0.10 kPa or more and 12.00 kPa or less on a substrate of hydrogel A.

[0008] Item 2. The method according to Item 1, wherein the modulus of rigidity of the hydrogel B when swollen is 0.60 kPa or more and 6.00 kPa or less.

[0009] Item 3. The method according to Item 1 or 2, wherein the modulus of rigidity of the hydrogel A at the time of preparation is 0.10 kPa or more and 8.00 kPa or less.

[0010] Item 4. The method according to any one of Items 1 to 3, wherein the ratio of the rigidity modulus of the hydrogel B when swollen to the rigidity modulus of the hydrogel A when prepared is 0.20 or more and 4.00 or less.

[0011] Item 5. The method according to Item 4, wherein the ratio of the rigidity modulus of the hydrogel B when swollen to the rigidity modulus of the hydrogel A when prepared is 0.20 or more and less than 1.00.

[0012] Item 6. The method according to any one of Items 1 to 5, wherein the hydrogels A and B are crosslinked acrylic resins.

[0013] Item 7. The manufacturing method according to any one of Items 1 to 6, further comprising forming a concave-convex pattern by leaving the film after formation.

[0014] Item 8. The manufacturing method according to Item 7, comprising contacting the film with water after forming the concave-convex pattern.

[0015] Item 9. The manufacturing method according to any one of Items 1 to 8, wherein the thickness of the film formed on the substrate is non-uniform and / or the film is formed only on a portion of the substrate.

[0016] Item 10. The manufacturing method according to any one of Items 1 to 9, wherein the concave-convex pattern is a structure that mimics the surface of biological tissue.

[0017] Item 11. A concave-convex pattern structure obtained by the manufacturing method according to any one of items 1 to 10.

[0018] Item 12. A transfer of the concave-convex pattern structure of the concave-convex pattern structure according to Item 11, or a transfer of the concave-convex pattern structure of the transfer.

[0019] Item 13. The transfer material according to Item 12, which is in the form of a sheet. [Effects of the Invention]

[0020] According to the present invention, it is possible to provide a simple manufacturing technique for a concave-convex pattern structure that can mimic the structure and softness of the surface of biological tissue. [Brief explanation of the drawings]

[0021] [Figure 1] 1 shows photographs of a gel in the AP state and a gel in the ES state subjected to a rheological test (Test Example 1). [Figure 2] 1 shows a schematic diagram of a method for producing a two-layer hydrogel in Test Example 2. [Figure 3] 1 shows a cross-sectional view of the bilayer hydrogel prepared in Test Example 2. The left side is a sample with a constant membrane thickness, and the right side is a sample with a gradient in membrane thickness. [Figure 4] This is a photograph showing the formation of a concave-convex pattern on Bilayer I. t is the time elapsed after the membrane solution was poured onto the substrate. [Figure 5] This is a photograph showing the formation of a concave-convex pattern on Bilayer II. t is the time elapsed after the membrane solution was poured onto the substrate. [Figure 6] This is a photograph showing the formation of a concave-convex pattern on Bilayer III. t is the time elapsed after the membrane solution was poured onto the substrate. [Figure 7] 1 shows a photograph of a concave-convex pattern formed when a film is formed only on a part of a substrate. DETAILED DESCRIPTION OF THE INVENTION

[0022] In this specification, the expressions "contain" and "comprise" include the concepts of "contain," "comprise," "consist essentially of," and "consist only of."

[0023] In one aspect, the present invention relates to a method for producing a concave-convex pattern structure (sometimes referred to herein as the "production method of the present invention"), which comprises forming a film of hydrogel B having a modulus of rigidity when swollen of 0.10 kPa or more and 12.00 kPa or less on a substrate of hydrogel A. This method will be described below.

[0024] A hydrogel is a gel-like substance that contains water, and can be formed, for example, by crosslinking hydrophilic polymers.

[0025] Examples of hydrophilic polymers include artificially synthesized synthetic polymers (synthetic resins), more specifically, synthetic polymers such as acrylic resins such as polyacrylamide, polyethylene oxide, polyvinylpyrrolidone, polyvinyl alcohol, and polyethylene glycol.

[0026] Other examples of hydrophilic polymers include polysaccharides such as dextrin, dextran, chitin, chitosan, agar, agarose, gellan gum, xanthan gum, karaya gum, carrageenan, cellulose, and starch; proteins such as collagen, gelatin, fibrin, albumin, laminin, keratin, ovalbumin, myosin, globulin, and peptides; and nucleic acids such as DNA and RNA.

[0027] As the hydrogel, a crosslinked acrylic resin is preferred, and an acrylamide gel is particularly preferred, from the viewpoint that it is more suitable for imitating the structure and softness of the surface of biological tissue (particularly the brain).

[0028] The hydrogel may be one in which only one type of hydrophilic polymer is cross-linked (bonded) to another, or may be one in which two or more types of hydrophilic polymers are cross-linked (bonded) to another.

[0029] The manufacturing method of the present invention is characterized by forming a film of hydrogel B on a substrate of hydrogel A. Although the film of hydrogel B is relatively soft, it absorbs water from hydrogel A and swells, without the need for solvent immersion or the like, and a concave-convex pattern can be formed by the mechanical action between it and the film of hydrogel A.

[0030] In the production method of the present invention, the modulus of rigidity of Hydrogel B when swollen is 0.10 kPa or more and 12.00 kPa or less. It was unexpected that a concave-convex pattern can be formed even on a film made of such a soft hydrogel.

[0031] The swollen rigidity is the rigidity measured when the hydrogel is completely swollen with water. Specifically, it can be measured according to or in accordance with the method described in "1-3. Rheology test" in Test Example 1 below.

[0032] From the viewpoint of being more suitable for mimicking the structure and softness of the surface of biological tissue (particularly the brain), the modulus of rigidity of Hydrogel B when swollen is preferably 0.20 kPa or more and 10.00 kPa or less, more preferably 0.40 kPa or more and 8.00 kPa or less, even more preferably 0.60 kPa or more and 6.00 kPa or less, still more preferably 0.80 kPa or more and 4.00 kPa or less, particularly preferably 1.00 kPa or more and 3.00 kPa or less, and particularly preferably 1.20 kPa or more and 2.00 kPa or less.

[0033] The rigidity of the hydrogel B at the time of preparation is not particularly limited as long as it satisfies the above rigidity when swollen.

[0034] The rigidity modulus at the time of preparation is the rigidity modulus measured immediately after preparation of the hydrogel used in the production method of the present invention (at the end of the gelation reaction of the solution of water and hydrophilic polymer). Specifically, it can be measured according to or in accordance with the method described in "1-3. Rheology test" in Test Example 1 below.

[0035] The rigidity modulus of Hydrogel B at the time of preparation is preferably 1.00 kPa or more and 25.00 kPa or less, more preferably 2.00 kPa or more and 20.00 kPa or less, even more preferably 4.00 kPa or more and 15.00 kPa or less, even more preferably 6.00 kPa or more and 12.00 kPa or less, and particularly preferably 8.00 kPa or more and 10.00 kPa or less.

[0036] The rigidity modulus of hydrogel A at the time of preparation is not particularly limited as long as it is capable of forming a concave-convex pattern, but from the viewpoint of being more suitable for imitating the structure and softness of the surface of biological tissue (particularly the brain), it is preferably 0.10 kPa or more and 8.00 kPa or less, more preferably 0.40 kPa or more and 5.00 kPa or less, even more preferably 0.70 kPa or more and 3.00 kPa or less, and even more preferably 1.00 kPa or more and 2.50 kPa or less.

[0037] The rigidity modulus of hydrogel B when swollen is not particularly limited as long as it is capable of forming a concave-convex pattern, but from the viewpoint of being more suitable for imitating the structure and softness of the surface of biological tissue (particularly the brain), it is preferably 0.05 kPa or more and 5.00 kPa or less, more preferably 0.10 kPa or more and 3.00 kPa or less, even more preferably 0.20 kPa or more and 2.00 kPa or less, and particularly preferably 0.40 kPa or more and 1.50 kPa or less.

[0038] The ratio of the rigidity modulus of hydrogel B when swollen to the rigidity modulus of hydrogel A when prepared is not particularly limited as long as it is possible to form a concave-convex pattern, but from the viewpoint of being more suitable for imitating the structure and softness of the surface of biological tissue (particularly the brain), it is preferably 0.20 or more and 4.00 or less, more preferably 0.20 or more and 3.00 or less, even more preferably 0.20 or more and 2.00 or less, still more preferably 0.20 or more and 1.00 or less (or less), particularly preferably 0.40 or more and 0.95 or less, and particularly preferably 0.60 or more and 0.95 or less.

[0039] The ratio of the swelling coefficients of hydrogels A and B (w ES / w AP ) is not particularly limited as long as it is possible to form a concave-convex pattern, but from the viewpoint of being more suitable for imitating the structure and softness of the surface of biological tissue (particularly the brain), it is preferably 0.50 to 10.00, more preferably 1.00 to 8.00, even more preferably 2.00 to 6.00, and even more preferably 3.00 to 5.50.

[0040] Swelling coefficient ratio (w ES / w AP ) can be measured according to or in accordance with the method described in "1-2. Swelling degree test" in Test Example 1 below.

[0041] Hydrogels can be produced according to or in accordance with known methods. Specifically, for example, an aqueous solution containing a hydrophilic polymer (and optionally a crosslinker) (preferably a water content of 70% by mass or more, 80% by mass or more, 90% by mass or more, 95% by mass or more, 99% by mass or more, or 100% by mass or more relative to 100% by mass of the solvent) can be gelled (for example, by standing, heating, cooling, etc.). The ratio of the rigidity modulus and swelling coefficient of the hydrogel can be adjusted appropriately, for example, by adjusting the concentration and type of the hydrophilic polymer and / or crosslinker constituting the hydrogel. For this adjustment, previous reports (for example, Soft Matter, 2021, 17, 4979-4988) can be referenced as necessary. When the hydrogel is a crosslinked acrylic resin (e.g., polyacrylamide gel), hydrogel A and hydrogel B can be produced using an aqueous solution with an acrylamide concentration of 1000 to 8000 mM and a crosslinker (e.g., N,N-methylenebisacrylamide) concentration of 0.5 to 8 mM.

[0042] The shape of the substrate is not particularly limited, and may be, for example, a flat plate, or may have a curved surface, bent portions, or the like.

[0043] The thickness of the base is not particularly limited as long as it is possible to form a relief pattern, but from the viewpoint of being more suitable for imitating the structure and softness of the surface of biological tissue (particularly the brain), it is, for example, 0.5 to 20.0 mm, preferably 1.0 mm to 15.0 mm, more preferably 1.5 mm to 10.0 mm, even more preferably 2.0 mm to 7.0 mm, and even more preferably 3.0 mm to 6.0 mm.

[0044] The shape of the film formed on the substrate is not particularly limited, and it usually follows the shape of the substrate.

[0045] The thickness of the film is not particularly limited as long as it can form a concave-convex pattern, but from the viewpoint of being more suitable for imitating the structure and softness of the surface of biological tissue (particularly the brain), it is, for example, 0.1 to 5.0 mm, preferably 0.2 to 3.0 mm, more preferably 0.3 to 2.0 mm. By making the film thicker, a clearer concave-convex pattern can be obtained.

[0046] In a preferred embodiment of the present invention, the thickness of the film formed on the substrate is non-uniform, and / or the film is formed only on a portion of the substrate, thereby making it possible to form multiple types of uneven patterns on the substrate that are different from one another (for example, different widths or depths / heights of the grooves / ridges), or to form uneven patterns only on a portion of the substrate.

[0047] The method for forming the hydrogel A substrate is not particularly limited, but a typical method involves pouring the hydrogel A forming solution A into a container that will serve as a mold for the desired substrate shape, and then allowing it to gel.

[0048] After the gelling reaction of forming solution A is completed and a base of hydrogel A is formed, a film of hydrogel B is formed on the base of hydrogel A. This method is also not particularly limited, and in the case of the typical example described above, a method can be used in which forming solution B of hydrogel B is poured onto the base of a container, followed by gelation.

[0049] After the gelling reaction of forming solution B is completed and a film of hydrogel B is formed, the solution is left to stand, allowing the formation of a concave-convex pattern. The standing time is long enough for the solution to absorb water from hydrogel A, swell, and generate a mechanical interaction with the film of hydrogel A, for example, 30 minutes to 200 hours, and preferably 1 hour to 100 hours.

[0050] During this standing, it is not necessary to add a solvent such as water. Therefore, in one embodiment, the standing can be carried out without bringing water into contact with the film. On the other hand, after the formation of the concave-convex pattern, bringing water into contact with the film can make the concave-convex pattern more distinct. When contacting with water, the contact time is, for example, 5 hours to 200 hours, preferably 20 hours to 100 hours.

[0051] According to the manufacturing method of the present invention, a structure having a concave-convex pattern on its surface (convex-convex pattern structure) can be manufactured.

[0052] The ratio (X / Y) of the height of the peaks (X: the difference between the height of the center of the peak and the height of the nearest peak) to the width of the peaks (Y: the width of the peak) of the peak pattern in the peak-peak structure is, for example, less than 1, preferably 0.1 or more and less than 1.

[0053] The distance between valleys of the concave-convex pattern in the concave-convex pattern structure (the length between a concave portion and the nearest concave portion across one convex portion) is, for example, less than 15 mm, preferably 0.1 mm or more and less than 15 mm. In a preferred embodiment of the present invention, the structure may include a region where the distance is 0.1 mm or more and less than 1 mm, and a region where the distance is 1 mm or more (preferably 3 mm or more, 5 mm or more, 7 mm or more, 10 mm or more) and less than 15 mm.

[0054] The above parameters relating to the concave-convex pattern can be calculated as the average value of measurements taken at 10 randomly selected points.

[0055] By adopting the manufacturing method of the present invention, it is possible to form a structure that mimics the surface of biological tissue, which also mimics its softness. The manufacturing method of the present invention is particularly suitable for forming a structure that mimics the surface of the brain (i.e., a structure that mimics the wrinkles of the brain).

[0056] The production method of the present invention does not require the use of an organic solvent and is therefore excellent in terms of safety. Furthermore, the production method of the present invention is a method of forming a two-layer hydrogel and is therefore excellent in terms of simplicity.

[0057] The manufacturing method of the present invention and the concave-convex pattern structure obtained by the manufacturing method of the present invention can be used, for example, to elucidate the mechanism of formation of concave-convex patterns on the surface of biological tissue, to elucidate the pathology of diseases exhibiting abnormal concave-convex patterns (for example, in the brain, lissencephaly, schizencephaly, etc.), and to develop treatment strategies.

[0058] For example, a transfer of the concave-convex pattern structure of the concave-convex pattern structure of the present invention, or a transfer of the concave-convex pattern structure of the transfer can be used. The transfer can be obtained according to a known method, for example, by laminating a liquid or flexible resin on the concave-convex pattern surface of the concave-convex pattern structure of the present invention and then curing the resin as needed. The resin is not particularly limited as long as it has physical properties that allow it to be immersed in the valleys of the concave-convex pattern, and for example, a silicone elastomer such as PDMS can be used. The shape of the transfer is not particularly limited, but it can be, for example, sheet-like, or may have a curved surface. The transfer can be used, for example, as a scaffold or mold for creating a cell sheet. [Example]

[0059] The present invention will be described in detail below based on examples, but the present invention is not limited to these examples.

[0060] Test Example 1. Preparation of hydrogel and measurement of physical properties <1-1. Materials> We fabricated several polyacrylamide hydrogel samples with different monomer amounts and crosslink densities. Because hydrogels have a high water content per volume, we were able to investigate how the number of polymer chains dissolved in the solution and the crosslinking points affect the elastic modulus. The materials used to fabricate these hydrogels were acrylamide (AAm), N,N-methylenebisacrylamide (BIS), ammonium persulfate (APS), and N,N,N',N'-tetramethylethylenediamine (TMEDA). AAm forms the main chain of the polyacrylamide hydrogel. BIS is a crosslinking agent that crosslinks the AAm main chains. The swelling and rigidity of the polyacrylamide hydrogel can be controlled by varying the molar concentrations of AAm and BIS. The molar concentrations of AAm and BIS are shown in Table 1. The amounts of the polymerization initiator (APS) and polymerization accelerator (TMEDA) were kept constant at 5 mM and 10 mM, respectively.

[0061] <1-2. Swelling test> <1-2-1. Sample Preparation> The acrylamide hydrogel samples were prepared as follows. First, pure water was prepared in a beaker. Next, the required amounts of AAm and BIS were weighed using an electronic balance and added to the pure water in the beaker and stirred. After stirring, the solution was wrapped in plastic wrap and bubbled with nitrogen for approximately 60 minutes to remove oxygen from the solution. Next, APS was added to the bubbled solution and stirred thoroughly. Finally, TMEDA was added to the solution and quickly stirred with a glass stirring rod. The solution was poured into a 66 mm diameter flat petri dish (FS-60, AS ONE) with a lid to a thickness of 4 mm to prepare the sample. The solution was wrapped in plastic wrap to prevent evaporation and left to stand for approximately 60 minutes until the reaction was complete.

[0062] <1-2-2.Measurement method> The polyacrylamide hydrogel used in this study is considered to have three swelling states: an ideally dried state (ID), an as-prepared state (AP), and a fully swollen state (ED). In this study, the volume swelling ratio J is evaluated based on the ID state. The relationship between the volume and mass of the gel under the assumption of incompressibility is expressed as follows:

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[0068] <1-3. Rheology test> <1-3-1. Sample Preparation> An aqueous solution was prepared using the same procedure as in the swelling test. The solution was then poured into a cylindrical silicone rubber mold (45-55 mm in diameter, 1 mm thick) and molded by sandwiching it between two petri dishes (Figure 1). The solution was wrapped in plastic wrap to prevent evaporation and left to stand for approximately 60 minutes until the reaction was complete.

[0069] Rotational shear tests were performed to measure the elastic modulus mechanically. A rheometer (Discovery HR-1, manufactured by TA Instruments) was used for the tests, with a 40 mm diameter aluminum parallel plate geometry. First, the shear strain was varied from 0.02% to 20% at a fixed frequency of 1 Hz to estimate the linear region of the storage modulus G' and loss modulus G''. This region varies depending on the compound formulation. Tests were then performed at a constant angular frequency of 0.1 rad / s under selected strains (0.1-2%) within the proportional elastic region to measure the storage and loss moduli, and the shear modulus G''. AP It was decided that:

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[0072] <1-4.Results> The measurement results are shown in Table 1. AAM is the acrylamide concentration in the gel-forming solution, and C BIS indicates the concentration of N,N-methylenebisacrylamide in the gel-forming solution. G AP indicates the modulus of rigidity at the time of gel preparation (immediately after gel preparation), and G ES indicates the shear modulus when swollen (when the gel is completely swollen) (1.3. Rheological Test). ES / w AP indicates the mass swelling ratio.

[0073] [Table 1]

[0074] Test Example 2. Production of pattern material In this study, bilayer hydrogels consisting of a substrate and a gel film were used as experimental samples. The concentrations of the monomer acrylamide (AAm: Acrylamide) in the gel-forming solution, the cross-linking agent N,N'-methylenebisacrylamide (BIS: N,N'-methylenebisacrylamide) in the gel-forming solution, and the physical properties of the hydrogels that make up the prepared bilayer hydrogels (Bilayer I, Bilayer II, and Bilayer III) are shown in Table 2. The amounts of the polymerization initiator (APS) and polymerization accelerator (TMEDA) were kept constant at 5 mM and 10 mM, respectively. The shear modulus (G AP ) relative to the swelling modulus of the hydrogel that constitutes the membrane (G ES ) ratio (Film G ES / Subtrate G AP) was 0.81 for Bilayer I, 2.68 for Bilayer II, and 6.58 for Bilayer III.

[0075] [Table 2]

[0076] First, pure water was measured into a beaker, and AAm and BIS were added to prepare the substrate solution (Solution 1) and the membrane solution (Solution 2). Approximately 3 mL of the measured pure water was transferred to another container, and 5 mM of the polymerization initiator ammonium persulfate (APS) was added and stirred. To facilitate pattern observation, the membrane solution was colored by mixing it with blue powder paint (Ultramarine, Kusakabe Co. Ltd.). Afterwards, nitrogen gas was bubbled through the solution for approximately 1 hour to remove oxygen, which inhibits the gelation reaction.

[0077] After bubbling, the APS aqueous solution transferred to a separate container was added to the substrate solution and gently stirred. After that, the required amount was measured and 10 mM of N,N,N,N'-Tetramethylenediamine (TMEDA: N,N,N,N'-Tetramethylenediamine) was added as a polymerization accelerator and further stirred. After that, the mixture was placed in an acrylic container (120 × 120 × 36 mm). 3 The substrate was fabricated by gently pouring the solution into a slab and leaving it to stand. To create a slope on the substrate surface, the acrylic container was placed on a tilt stage that could be adjusted to the desired angle before pouring the substrate solution into it. Samples without a slope on the substrate were also fabricated. Both samples were left at room temperature for 40 minutes until the reaction was complete and gelation occurred. In this study, the thickness of the samples with a sloped substrate was 4.0-5.0 mm, and the thickness of the samples with a constant substrate thickness was 5 mm.

[0078] After the gelation of the substrate was complete, the required amount of solution, which was a mixture of the APS aqueous solution and TMEDA transferred to a separate container, was measured and poured onto the substrate. At this time, the sample was placed on a horizontal table so that the surface of the film was horizontal. Here, samples with a slope on the substrate surface would also have a slope on the film (Figure 2). The amount of solution was adjusted so that the film thickness was 1 mm for samples with a constant thickness, and 0.5-1.5 mm for samples with a slope (Figure 3).

[0079] For some samples, an acrylic resin mold printed with a 3D printer (AGILISTA-3200, Keyence) was floated on the solution while the substrate solution was being gelled, creating a substrate with a depression on its surface. The membrane solution was then gently poured into the depression and allowed to gel, creating a sample in which the membrane was present only in a small area of ​​the substrate.

[0080] For Bilayer I, Bilayer II, and Bilayer III, the membrane solution was poured onto the substrate and allowed to stand for 2 hours without external water supply. Water was then supplied onto the membrane and allowed to stand for an additional 72 hours. The results are shown in Figures 4–6. Conventional techniques have believed that the formation of a concave-convex pattern requires a high membrane rigidity, as in Bilayer III. Our results demonstrate that concave-convex patterns can be formed even with Bilayer I and Bilayer II, which have low membrane rigidity when swollen. The resulting concave-convex patterns mimic the surface structures of biological tissues, such as the brain and digestive tract (especially the brain), in terms of pattern size and shape. Furthermore, the use of a hydrogel with a low membrane rigidity makes them excellent tissue-mimicking structures. Furthermore, by simply varying the membrane thickness, we were able to form multiple concave-convex patterns (heterogeneous concave-convex patterns) with different patterns, shapes, and sizes within the same surface. Biological tissues may have locally different concave-convex patterns due to factors such as the tissue growth stage or pathogenesis, and this may be easily reproduced. In addition to varying the thickness of the film on the substrate as shown in Figures 4 to 6, it is also possible to form a non-uniform uneven pattern on the same surface by forming a film only on a part of the substrate (Figure 7).

Claims

1. A method for producing a concave-convex pattern structure, comprising forming a film of hydrogel B having a modulus of rigidity when swollen of 0.10 kPa or more and 12.00 kPa or less on a substrate of hydrogel A.

2. The method according to claim 1, wherein the modulus of rigidity of the hydrogel B when swollen is 0.60 kPa or more and 6.00 kPa or less.

3. The method according to claim 1, wherein the modulus of rigidity of the hydrogel A at the time of preparation is 0.10 kPa or more and 8.00 kPa or less.

4. 2. The method according to claim 1, wherein the ratio of the shear modulus of said hydrogel B when swollen to the shear modulus of said hydrogel A when prepared is 0.20 or more and 4.00 or less.

5. The method according to claim 4, wherein the ratio of the shear modulus of the hydrogel B when swollen to the shear modulus of the hydrogel A when prepared is 0.20 or more and less than 1.

00.

6. The method according to any one of claims 1 to 5, wherein the hydrogels A and B are crosslinked acrylic resins.

7. The method according to any one of claims 1 to 5, further comprising forming a concave-convex pattern by leaving the film after formation.

8. The method according to claim 7 , further comprising contacting the film with water after forming the concave-convex pattern.

9. The manufacturing method according to any one of claims 1 to 5, wherein the thickness of the film formed on the substrate is non-uniform and / or the film is formed only on a part of the substrate.

10. The manufacturing method according to any one of claims 1 to 5, wherein the concave-convex pattern has a structure that mimics the surface of biological tissue.

11. A concave-convex pattern structure obtained by the manufacturing method according to any one of claims 1 to 5.

12. A transfer of the concave-convex pattern structure of the concave-convex pattern structure according to claim 11, or a transfer of the concave-convex pattern structure of the transfer.

13. The transfer body according to claim 12, which is in the form of a sheet.

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