Composite, method for producing composite, and use of composite

Abstract

One embodiment of the composite body according to the present disclosure is provided with: a first member comprising a first carbon material; a second member comprising a second carbon material; and a network body of carbon nanotubes positioned between the first member and the second member and in contact with each of the first member and the second member.

Description

TECHNICAL FIELD

[0001] The present application relates to a composite, a method for manufacturing a composite, and a use of a composite. BACKGROUND

[0002] As a use of carbon nanotubes, there is a proposal to form a plurality of carbon nanotubes into a product such as a heating element. For example, Patent Literature 1 proposes a surface heat source having a rectangular heating element in which a carbon nanotube film is laminated, and two electrodes connected to both end portions of the heating element. PRIOR ART DOCUMENTS PATENT LITERATURE

[0003] Patent Literature 1: Japanese Patent Application Laid-Open No. 2010-257971 SUMMARY PROBLEMS TO BE SOLVED BY THE INVENTION

[0004] Although there is a proposal to use a carbon nanotube film for a product such as a heating element, once the carbon nanotube film is manufactured, the carbon nanotube films are not usually bonded to each other even if the carbon nanotube films are overlapped with each other and the overlapped portions are pressed. In addition, when a carbon nanotube film is used for a product or the like, in order to utilize it without impairing the electrical characteristics or the like of the carbon nanotube film, it is desirable that the carbon nanotube films are bonded to each other without using an adhesive containing a resin such as an epoxy resin or the like.

[0005] Therefore, an object of the present application is to provide a composite in which members containing a carbon material are bonded to each other without using an adhesive containing a resin, and a method for manufacturing the same. MEANS FOR SOLVING THE PROBLEMS

[0006] One form of the composite of the present application includes a first member containing a first carbon material, a second member containing a second carbon material, and a network of carbon nanotubes positioned between the first member and the second member and in contact with the first member and the second member, respectively. EFFECTS OF THE INVENTION

[0007] According to the present application, it is possible to provide a composite in which members containing a carbon material are bonded to each other without using an adhesive containing a resin, and a method for manufacturing the same. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 is a schematic cross-sectional view of one embodiment of a composite. Figure 2 is a schematic cross-sectional view of one embodiment of a composite. Figure 3 is a plan view of a carbon nanotube forest and a carbon nanotube network illustrating a method for manufacturing a carbon nanotube network. Figure 4 yes Figure 3 A sectional view along line AA. Detailed Implementation

[0009] An example of an embodiment of the present disclosure will now be described in detail with reference to the accompanying drawings. Furthermore, the accompanying drawings used in the following description are sometimes enlarged to facilitate understanding of the features of the present disclosure. Therefore, the dimensions and proportions of each component may sometimes differ from the actual dimensions.

[0010] In this specification, the numerical range A to B refers to values ​​above A and below B. In this specification, when the units of the values ​​before and after the "~" indicating a numerical range are the same, the unit of the value before the "~" may sometimes be omitted.

[0011] In this specification, carbon nanotubes are also referred to as "CNTs", carbon nanotube forests are also referred to as "CNT forests", carbon nanotube fibers are also referred to as "CNT fibers", and carbon nanotube networks are also referred to as "CNT networks".

[0012] In this specification, "parallel" includes not only parallel in the strict sense but also approximately parallel. Regarding parallelism, the angle between two objects can be less than 30°, less than 20°, less than 10°, or less than 5°. Similarly, "perpendicular" and "orthogonal" include not only perpendicularity in the strict sense but also approximately perpendicularity and orthogonality, respectively. For perpendicularity and orthogonality, the angle between two objects can be greater than 60° and less than 90°, greater than 70° and less than 90°, greater than 80° and less than 90°, or greater than 85° and less than 90°.

[0013] [Complex] The composite disclosed herein comprises a first component containing a first carbon material, a network of carbon nanotubes, and a second component containing a second carbon material. The network of carbon nanotubes is located between the first and second components. The network of carbon nanotubes is respectively connected to the first and second components.

[0014] Figure 1 and Figure 2 The composite 1 shown includes a first component 10, a second component 20, and a CNT mesh 30 located between the first component 10 and the second component 20. The CNT mesh 30 is connected to the first component 10 and to the second component 20.

[0015] <Network structure of carbon nanotubes> The composite has a carbon nanotube network (CNT network). CNT reticular formation refers to a reticular formation containing multiple CNT fibers. A CNT network can be, for example, an assembly of multiple CNT fibers extending in one direction and arranged perpendicular to that direction when viewed from above. "Viewed from above" refers to a planar CNT network viewed from its normal direction.

[0016] A CNT network can also be, for example, an assembly comprising, when viewed from above, multiple CNT fibers extending along a first direction and arranged in a direction perpendicular to the first direction, and multiple CNT fibers extending along a second direction and arranged in a direction perpendicular to the second direction, wherein the first and second directions intersect. The angle between the first and second directions is not particularly limited. For example, the first and second directions can be orthogonal. A CNT network can also include multiple CNT fibers extending along an nth direction and arranged in a direction perpendicular to the nth direction (n is an integer of 3 or more).

[0017] In the aforementioned composite, the first and second components are bonded together by a CNT mesh. That is, the CNT mesh serves to bond the components containing carbon material together.

[0018] In conventional carbon nanotube (CNT) films, the surface energy caused by the van der Waals forces of CNTs is stabilized, resulting in low adhesion between CNT films. Therefore, even when CNT films are overlapped and pressure is applied to the overlapping portion, they typically do not adhere to each other. In contrast, CNT networks, compared to CNT films, are presumably designed to maintain the high surface energy caused by the van der Waals forces of CNTs, thus exhibiting greater adhesive strength. For this reason, CNT networks can enable the adhesion of carbon-containing components such as CNT films.

[0019] CNT meshes can be manufactured using CNT fibers. CNT fibers can be manufactured, for example, by pulling multiple CNTs from a CNT forest. CNT meshes can be manufactured, for example, by pulling multiple CNTs from a CNT forest, specifically by pulling multiple CNTs into a sheet. The size of the CNT mesh can be adjusted by changing the width of the CNTs pulled from the CNT forest.

[0020] A CNT forest refers to an aggregate of multiple CNTs arranged on a substrate and oriented in a direction perpendicular to the substrate surface. In a CNT forest, multiple CNTs stand side by side on the substrate.

[0021] CNT forests can be obtained, for example, by chemical vapor deposition (CVD) using a catalyst substrate having a substrate and a catalyst layer disposed on the substrate. CVD is a method in which the catalyst substrate is placed in a reaction chamber, a feed gas is supplied to the reaction chamber, and CNTs are grown on the surface of the catalyst layer. Thermal CVD is preferred as the CVD method.

[0022] Examples of substrates include silicon substrates, alumina substrates, magnesium oxide substrates, glass substrates, sapphire substrates, and stainless steel substrates.

[0023] The catalyst layer can be formed, for example, by sputtering catalyst particles onto a substrate. Catalysts can be metals, specifically alloys containing at least one metal selected from iron (Fe), nickel (Ni), cobalt (Co), molybdenum (Mo), and gold (Au). Examples of alloys include ferroalloys, nickel alloys, and cobalt alloys. Catalysts can be metal precursors such as metal oxides and metal compounds. Examples of metal oxides include iron oxides, nickel oxides, and cobalt oxides. Examples of metal compounds include ferric chloride. When using precursors, they need to be converted into metals before CVD by heating or the like.

[0024] The catalyst substrate described above may have a buffer layer between the substrate and the catalyst layer. Examples of materials used for the buffer layer include silicon dioxide (SiO2), aluminum oxide (Al2O3), silicon nitride (SiN), zinc oxide (ZnO), copper oxide (Cu2O), and nickel oxide (NiO). The buffer layer can be formed, for example, by sputtering.

[0025] Sputtering for forming a catalyst layer and sputtering for forming a buffer layer can be carried out according to the sputtering target using known apparatus and conditions. The sputtering pressure is preferably 0.01 to 10 Pa, more preferably about 0.1 to 1 Pa.

[0026] Carbon-containing gases can be used as feedstock gases, such as hydrocarbons, sulfur-containing organic gases, phosphorus-containing organic gases, carbon monoxide, and alcohols. Examples of hydrocarbons include: alkanes such as methane and ethane; olefins such as ethylene and butadiene; alkynes such as acetylene; aromatics such as benzene, toluene, and styrene; aromatics with fused rings such as indene, naphthalene, and phenanthrene; cycloalkanes such as cyclopropane and cyclohexane; cycloolefins such as cyclopentene; and alicyclic hydrocarbons with fused rings such as steroids. Examples of alcohols include methanol and ethanol. From the viewpoint of the purity of the resulting CNTs, hydrocarbons are preferred as feedstock gases.

[0027] A carrier gas, which is supplied to the reaction chamber along with the raw material gas, can be used to transport the raw material gas. Examples of carrier gases include helium, neon, argon, nitrogen, and hydrogen.

[0028] From the perspective of CNT growth rate and the purity of the obtained CNTs, the temperature in the reaction chamber of the CVD method is preferably 600-850℃, more preferably 650-800℃. From the perspective of CNT growth rate and purity, the pressure inside the reaction chamber in the CVD process is preferably atmospheric pressure. However, depending on other conditions during the CVD process, the pressure inside the reaction chamber can also be atmospheric pressure with reduced pressure or pressurized pressure.

[0029] The average length of CNTs in a CNT forest is preferably 10–1000 μm, more preferably 30–800 μm, and even more preferably 50–500 μm. The average length of CNTs in a CNT forest can be adjusted, for example, by adjusting the CVD process time, i.e., the CNT growth time.

[0030] The average diameter of CNTs is preferably 1–50 nm, more preferably 3–30 nm, and even more preferably 5–15 nm. The average diameter of CNTs can be adjusted, for example, by adjusting the thickness of the catalyst layer and the type of catalyst.

[0031] The average length and average diameter of CNTs were determined using scanning electron microscopy (SEM) or transmission electron microscopy (TEM). Specifically, 10 CNT images were captured using SEM or TEM. For each of the 10 images, 10 length measurement points were randomly selected and measured, resulting in a total of 100 length measurements. The arithmetic mean of these 100 length measurements was then calculated to determine the average length of the CNT. Similarly, for each of the 10 images, 10 diameter measurement points were randomly selected and measured, resulting in a total of 100 diameter measurements. The arithmetic mean of these 100 diameter measurements was then calculated to determine the average diameter of the CNT.

[0032] The carbon purity of CNTs is preferably 95.0% to 99.999%. The lower limit of the carbon purity of CNTs is preferably 96.0%, more preferably 97.0%, even more preferably 98.0%, even more preferably 99.0%, and particularly preferably 99.8%. The upper limit of the carbon purity of CNTs can be, for example, 99.99% or 99.9%. The carbon purity of CNTs can be determined, for example, by elemental analysis using fluorescent X-rays.

[0033] The crystallinity of CNTs can be evaluated, for example, using Raman spectroscopy. In Raman-based crystallinity evaluation, the D / G ratio is used as an indicator. The D / G ratio is the ratio that appears at 1360 cm⁻¹ in the Raman spectrum. -1 The D / G ratio is the ratio of the peak intensity of the D band near 1580 cm⁻¹ to the peak intensity of the G band near 1580 cm⁻¹. The smaller the D / G ratio, the higher the crystallinity of the carbon nanotubes. The preferred D / G ratio for CNTs is 0.5 to 1.0, more preferably 0.6 to 0.8.

[0034] The purity and crystallinity of CNTs can be adjusted, for example, by adjusting the thickness of the buffer layer, the type of buffer layer, the thickness of the catalyst layer, the type of catalyst, the type and flow rate of the feed gas in the CVD process, and the temperature and pressure in the reaction chamber.

[0035] CNTs can be single-walled carbon nanotubes or multi-walled carbon nanotubes with two or more layers. From an adhesive point of view, multi-walled carbon nanotubes are preferred. The number of layers in multi-walled carbon nanotubes is not particularly limited, but is preferably 2 to 20.

[0036] A CNT network comprises multiple CNT fibers. Each CNT fiber contains multiple CNTs. A CNT fiber is a fiber in which multiple CNTs are oriented in one direction. In a CNT fiber, the length directions of the multiple CNTs are aligned in one direction.

[0037] The CNT mesh is preferably a CNT mesh obtained by pulling out multiple CNTs from a CNT forest disposed on a substrate, or a laminate of the CNT mesh within the range of exerting the above-mentioned adhesive force. A CNT mesh, for example, is an assembly of multiple CNT fibers extending in one direction and arranged perpendicular to that direction when viewed from above. Hereinafter, the direction in which the CNT fibers extend in a CNT mesh is also referred to as the "length direction of the CNT fibers".

[0038] CNT meshes can be manufactured, for example, by using tweezers or similar tools to pull out the CNTs at the ends of the CNT forest in a direction parallel to the surface of the substrate containing the CNT forest, away from the CNT forest. When the CNTs at the ends of the CNT forest are pulled out, the CNTs adjacent to the pulled-out CNTs are pulled out sequentially by van der Waals forces. The pulled-out CNTs are oriented with their growth direction aligned with the pulling direction. Therefore, the multiple CNTs constituting the CNT fibers are oriented in one direction. The multiple CNTs constituting the CNT fibers are bonded together by van der Waals forces. This results in a CNT mesh composed of multiple CNT fibers extending along the CNT pulling direction.

[0039] CNT mesh can be manufactured, for example, by contacting a rectangular device with the sidewalls or upper surfaces of the ends of the CNTs forming the CNT forest and moving the device away from the CNT forest in a direction parallel to the surface of the substrate containing the CNT forest.

[0040] The following illustration shows an example of a method for manufacturing CNT mesh. Figure 3 This is a top view illustrating the process of manufacturing a CNT mesh 50 using a CNT forest 42 disposed on a substrate 40. Figure 4 yes Figure 3 A sectional view along line AA.

[0041] Figure 3 and Figure 4 The CNT mesh 50 shown can be manufactured by pulling out multiple CNTs at the ends of a CNT forest 42 located on a substrate 40 and oriented in a direction perpendicular to the surface of the substrate 40 in a direction parallel to the surface of the substrate 40, away from the CNT forest 42, into a sheet. When viewed from above, the CNT fibers 52 constituting the CNT mesh 50 extend along the direction in which the CNTs are pulled out, and multiple CNT fibers 52 are arranged in a direction perpendicular to this direction.

[0042] As will be described later, a CNT mesh 50 can also be obtained by winding multiple CNTs pulled out in parallel from the CNT forest 42 onto the roller 60.

[0043] The aforementioned composite preferably has a CNT mesh or a stack of such CNT mesh between the first and second components, which is a CNT mesh obtained by pulling out multiple CNTs from a CNT forest.

[0044] A CNT mesh laminate can be manufactured, for example, by laminating the CNT meshes obtained by pulling multiple CNTs from a CNT forest into sheets, or by winding the CNT mesh obtained by pulling multiple CNTs from a CNT forest multiple times on the circumference of a roller to form a roller, and then cutting the roller along the axis of rotation. In the latter case, the number of CNT mesh layers is the number of times the CNT mesh is wound on the roller.

[0045] When multiple CNT meshes are made and then stacked to create a CNT mesh stack, the CNT meshes can be stacked in a manner where the length direction of the CNT fibers constituting one CNT mesh is parallel to the length direction of the CNT fibers constituting other CNT meshes, or they can be stacked in a cross manner (e.g., orthogonal).

[0046] Examples of CNT mesh shapes include rectangles, trapezoids, parallelograms, rhombuses, kites, ellipses, and circles.

[0047] From an adhesive point of view, the preferred unit area weight of the CNT mesh is 0.00113–0.17 mg / cm³. 2 More preferably 0.00113~0.017mg / cm³ 2 Further preferred concentrations are 0.00136–0.0136 mg / cm³. 2 From an operational point of view, the preferred weight per unit area of ​​the CNT network is 0.00113–0.17 mg / cm³. 2 More preferably 0.0113~0.17mg / cm³2 Further preferred concentrations are 0.0136–0.136 mg / cm³. 2 In the case where the CNT network is a stack of CNTs obtained by pulling CNTs from a CNT forest, the above-mentioned unit area weight is the unit area weight of the stack. The unit area of ​​a CNT network can be determined by measuring the mass of the CNT network using a balance or similar measuring instrument and then dividing that mass by the area of ​​the CNT network.

[0048] When the CNT mesh is a CNT mesh or a CNT mesh laminate, from the viewpoint of adhesion, the number of CNT mesh layers is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 3.

[0049] In one embodiment, the CNT fiber web is conductive only in the length direction of the CNT fibers and substantially non-conductive in the short side direction of the CNT fibers. In another embodiment, the laminate obtained by stacking CNT webs in a manner that aligns the length directions of the CNT fibers and arranges the CNT fibers in parallel has conductivity only in the length direction of the CNT fibers and substantially non-conductive in the short side direction of the CNT fibers.

[0050] <Components containing carbon materials> The composite disclosed herein comprises a first component containing a first carbon material and a second component containing a second carbon material.

[0051] Examples of carbon materials include carbon nanotubes and carbon fibers. Examples of carbon fibers include pitch-based carbon fibers, polyacrylonitrile (PAN)-based carbon fibers, phenolic resin-based carbon fibers, cellulose-based carbon fibers, and polyvinyl alcohol-based carbon fibers. From the viewpoint of the electrical and mechanical properties of the above composites, carbon nanotubes are preferred as the carbon material. There can be one type of carbon material or two or more types.

[0052] Examples of the first and second components include carbon nanotube membranes, carbon fiber membranes, carbon fiber paper, carbon fiber felt, carbon fiber mats, and carbon fiber cloth. The first and second components preferably consist substantially only of carbon materials. Carbon nanotube membranes are particularly preferred as the first and second components.

[0053] In the above-mentioned composite, at least a portion of the first component in contact with the CNT mesh preferably contains a first carbon material, and at least a portion of the second component in contact with the CNT mesh preferably contains a second carbon material.

[0054] The portions of the first and second components that are not in contact with the CNT mesh can be made of, for example, resin, fabric, metal, ceramic, or glass, or can be covered by resin, fabric, metal, ceramic, or glass. Furthermore, the entire composite can also be covered by resin or the like.

[0055] Examples of the aforementioned resins include epoxy resins, phenolic resins, polyamide resins, polyolefin resins, polystyrene resins, polycarbonate resins, polymethyl methacrylate resins, polyethylene terephthalate resins, polyethersulfone resins, cellulose ester resins, benzocyclobutene resins, vinyl chloride resins, and acrylic resins. Examples of materials that constitute the above-mentioned fabrics include cotton, linen, wool, silk, nylon fiber, polyester fiber, polyacrylonitrile fiber, and polyurethane fiber.

[0056] In the above-mentioned composite, all opposing surfaces of the first and second components may be bonded by a CNT mesh, or at least a portion of the opposing surfaces of the first and second components may be bonded by a CNT mesh.

[0057] The aforementioned composite may, for example, include multiple first and second components in a manner that sequentially comprises a second component, a CNT mesh, a first component, a CNT mesh, a second component, a CNT mesh, and a first component. Alternatively, multiple first components may be adhered to a surface of the second component.

[0058] The first carbon material contained in the first component and the second carbon material contained in the second component may be the same or different. Furthermore, the first component and the second component may be the same or different. In this specification, as described above, even the case where the first component and the second component are the same component is included within the concept of a composite. From the viewpoint of adhesion, the first component and the second component are preferably carbon nanotube membranes. Hereinafter, the carbon nanotube membrane will also be referred to as a "CNT membrane".

[0059] Examples of CNT membranes obtained by conventionally known methods include those obtained by: coating a dispersion of CNTs in a solvent onto a substrate, drying the dispersion to remove the solvent, and peeling the dried material off the substrate; filtering the dispersion using a filter or the like and drying the CNT aggregates deposited on the filter surface; uniformly dispersing CNTs on an airflow such as air and aggregating the CNTs on a surface such as a metal mesh; or fabricating multiple carbon nanotube fibers (CNT fibers), aggregating them, and applying pressure to the CNT fiber aggregates to bond the CNT fibers together. CNT membranes obtained by these methods are typically membranes composed of CNTs or CNT fibers.

[0060] CNT films can also be, for example, laminates of the aforementioned CNT meshes. In this case, the CNT meshes are laminated to a degree that cannot be described as meshes in appearance.

[0061] CNT mesh laminates can be manufactured, for example, by: laminating CNT meshes obtained by pulling multiple CNTs from a CNT forest into sheets; or by winding multiple CNTs from a CNT forest onto the circumference of a roller to form a roller, and then cutting the roller along its rotation axis.

[0062] When manufacturing a CNT film by stacking multiple CNT meshes after forming them into sheets, the CNT meshes can be stacked in a manner in which the length direction of the CNT fibers constituting one CNT mesh is parallel to the length direction of the CNT fibers constituting other CNT meshes, or they can be stacked in a cross manner (e.g., orthogonal).

[0063] Examples of CNT membrane shapes include rectangles, squares, trapezoids, parallelograms, rhombuses, kites, ellipses, and circles.

[0064] The weight per unit area of ​​the CNT film can be set according to the purpose of the composite and is not particularly limited. For example, from the viewpoint of productivity and adhesion, it is preferably 0.0226 to 170 mg / cm³. 2 More preferably 0.0339~85mg / cm 2 Further preferred concentrations are 0.0565–17 mg / cm³. 2 Furthermore, the area weight per unit area of ​​the CNT membrane is typically greater than that of the CNT mesh, preferably more than twice as great. The area weight per unit area of ​​the CNT membrane can be determined by measuring the mass of the CNT membrane and dividing that mass by the area of ​​the CNT membrane. When the CNT film is a laminate of CNT meshes, the number of CNT mesh layers in the CNT film can be set according to the purpose of the composite and there is no particular limitation. For example, from the viewpoint of productivity and adhesion, it is preferred to be 20 to 10,000, more preferably 30 to 5,000, and even more preferably 50 to 1,000.

[0065] The following describes the case where the first component and the second component are CNT meshes stacked in such a way that the CNT fibers are aligned in their longitudinal directions and parallel, and the CNT mesh is a laminated body obtained by stacking CNT meshes in such a way that the CNT fibers are aligned in their longitudinal directions and parallel. In this case, the composite may have the first component, the CNT mesh, and the second component arranged with the CNT fibers parallel, or it may have the first component, the CNT mesh, and the second component arranged with the CNT fibers crossed (e.g., orthogonal). From the viewpoint of adhesive strength, the composite preferably comprises the first component, the CNT mesh, and the second component in a manner in which the CNT fibers in the first component, the CNT mesh, and the second component are parallel.

[0066] In one embodiment, a CNT film obtained by stacking CNT meshes in such a way that the CNT fibers are aligned along their length and parallel is conductive only along the length of the CNT fibers and substantially non-conductive along the short sides of the CNT fibers.

[0067] The following describes the case where the first component and the second component are CNT meshes stacked in such a way that the CNT fibers are aligned along their longitudinal directions and parallel, resulting in a CNT film; and the CNT mesh is a laminated body obtained by stacking CNT meshes in such a way that the CNT fibers are aligned along their longitudinal directions and parallel. In this case, the first component, the second component, and the CNT mesh can be conductive along the longitudinal direction of the CNT fibers. Therefore, the composite of the first component, the CNT mesh, and the second component is conductive along the longitudinal direction of the CNT fibers, with the CNT fibers in the first component, the CNT mesh, and the second component arranged in a parallel manner.

[0068] [Manufacturing method of the composite] As a method for manufacturing the above-mentioned composite, for example, a step of preparing a first component containing a first carbon material, a CNT mesh, and a second component containing a second carbon material, and a step of bonding the first component and the second component together through the CNT mesh.

[0069] Examples of steps for bonding the first and second components via a CNT mesh include: pressing the overlapping portions after sequentially overlapping the first component, the CNT mesh, and the second component; and arranging the first and second components in a non-overlapping manner on one surface of the CNT mesh, pressing the overlapping portions of the first and second components with the CNT mesh, and then bending the CNT mesh so that it is pressed against the other surface of the CNT mesh. As a method of applying pressure to the overlapping portion, examples include pressing the overlapping portion by hand or a pressing roller, and applying weight to the overlapping portion.

[0070] In the process of preparing a first component containing a first carbon material, a CNT mesh, and a second component containing a second carbon material, the preparation of the CNT mesh is preferably performed just before the process of bonding the first and second components together via the CNT mesh. "Just before" means, for example, 0 seconds to 2 hours prior, 0 seconds to 1 hour prior, or 0 seconds to 30 minutes prior. Furthermore, "0 seconds" refers to the method of directly forming the CNT mesh on the first or second component and simultaneously overlapping it with another component.

[0071] Items containing carbon materials The disclosed article comprising carbon material includes: a carbon material-containing component having a first region and a second region, and a network of carbon nanotubes. The network of carbon nanotubes is located between the first region and the second region. The network of carbon nanotubes is respectively connected to the first region and the second region.

[0072] The carbon nanotube network (CNT network) of the above-mentioned article is the same CNT network as the carbon nanotube network of the above-mentioned composite, and can be manufactured by the same method as the CNT network of the above-mentioned composite.

[0073] The carbon material contained in the components of the aforementioned article may be, for example, the same carbon material contained in the first and second components of the aforementioned composite. The carbon material contained in the aforementioned article may be, for example, the same component as the first and second components of the aforementioned composite.

[0074] In the aforementioned components, preferably at least a portion of the portions of the first and second regions that are in contact with the CNT mesh contains carbon material.

[0075] The portions of the components of the aforementioned article that are not in contact with the CNT mesh may be made of, for example, resin, fabric, metal, ceramic, or glass, or may be covered by resin, fabric, metal, ceramic, or glass. For example, the same resin that can constitute the first and second components of the aforementioned composite can be used as the resin. For example, the same material that constitutes the fabric of the first and second components of the aforementioned composite can be used as the fabric.

[0076] The first and second regions of a component containing carbon material can be different regions on the same surface or regions on different surfaces.

[0077] The following describes the case where the carbon-containing component is a CNT mesh obtained by laminating CNT fibers in a manner that aligns the length directions of the CNT fibers and makes the CNT fibers parallel, and the CNT mesh is a laminate obtained by laminating CNT mesh in a manner that aligns the length directions of the CNT mesh or CNT fibers and makes the CNT fibers parallel. In this case, the article may have a CNT mesh between a first region and a second region of the carbon-containing component, with the CNT fibers in the first region, the CNT mesh, and the second region being parallel or the CNT fibers being crossed (e.g., orthogonal). From the viewpoint of adhesive strength, the above-described article has a first region, a CNT mesh, and a second region with the CNT fibers in the first region and the CNT mesh being parallel.

[0078] The aforementioned articles can be manufactured, for example, by bending a component containing carbon material into a CNT mesh, overlapping the first region, the CNT mesh, and the second region in such a way that the CNT mesh is connected to the first region and the second region, and then applying pressure to the overlapping portion. In the aforementioned articles, different areas of components containing carbon materials are bonded to each other without the use of adhesives containing resin.

[0079] [Applications of the composite] The aforementioned composite can be used, for example, as a heating element. As a heating element, an example is one in which the first component is primarily used as an electrode and the second component is primarily used as a heating element. Using the first component as an electrode means electrically connecting an external power source to the second component, which is the heating element, through the first component.

[0080] As a method for manufacturing a heating element, for example, a method may be described in which a first component and a second component are first bonded together by means of a CNT mesh to obtain a composite, and then a wire or the like connected to an external power source is connected to the first component to electrically connect the external power source to the composite.

[0081] The wires can extend from the outside of the composite and be fixed inside the first component, or they can be fixed to the surface of the first component with a conductive adhesive. Examples of conductive adhesives include silver paste.

[0082] When the above-mentioned composite has multiple first components, especially when the second component is bonded to multiple first components, one of the first components can be used as the electrode on the positive side and another first component can be used as the electrode on the negative side.

[0083] One embodiment of the above-described composite includes a plurality of first components serving as electrodes and a film-like second component. One surface of the film-like second component is also referred to as the "first surface," and the other surface is referred to as the "second surface."

[0084] The following describes a composite having a first component, a first component, a first component, a first component, a first component, a first component, a first component, and a second component, a membrane. The above-mentioned composite material possesses: Second component The first A member disposed by the CNT mesh in the first region (e.g., one end) of the second member, and The first B member is disposed in the second region (e.g., the other end) of the second member by means of a CNT mesh. Component 1A and Component 1B may be disposed on the same surface of the second component, or Component 1A may be disposed on the first surface of the second component and Component 1B may be disposed on the second surface of the second component.

[0085] The following describes a composite having a first electrode component, a first component, a first component, a first component, a first component, a first component, a first component, a first component, a first component, a first component, a first component, a second component, a membrane-like component. The above-mentioned composite material possesses: Second component The first A member, which is disposed of by a CNT mesh on the first surface of the first region (e.g., one end) of the second member, The first C member, disposed on the second surface of the first region (e.g., one end) of the second member, is provided by a CNT mesh. The first B member, which is disposed of by a CNT mesh on the first surface of the second region (e.g., the other end) of the second member, and The first D member is provided by a CNT mesh on the second surface of the second region (e.g., the other end) of the second member.

[0086] The composite material in the first region sequentially comprises a first A member, a CNT mesh, a second member, a CNT mesh, and a first C member along the stacking direction. The composite material in the second region sequentially comprises a first B member, a CNT mesh, a second member, a CNT mesh, and a first D member along the stacking direction.

[0087] The first component is disposed on the second component via a CNT mesh, and the first component and the second component are electrically connected. That is, components 1A to 1D are respectively electrically connected to the second component. By electrically connecting the first component to an external power source via wires or the like and applying a voltage to the second component to allow current to flow, the second component will generate heat. Therefore, such a composite can be used as a heating element.

[0088] From the viewpoint of the heating element's thermal properties, the first and second components are preferably a CNT film obtained by stacking a CNT mesh in a parallel manner with CNT fibers, and the CNT mesh is a laminate obtained by stacking CNT meshes or CNT fibers in a parallel manner. The composite comprises the first component, the CNT fiber mesh, and the second component in a manner where the CNT fibers in the first component, the CNT mesh, and the second component are parallel. In this case, the carbon nanotube fibers contained in the second component are arranged in a manner extending from the first region of the second component to the second region, that is, from the first A component to the first B component.

[0089] The portion of the second component in the aforementioned composite that is not in contact with the first component or wires may also be covered by resin or the like. Examples of such resins include epoxy resin, phenolic resin, polyamide resin, polyolefin resin, polystyrene resin, polycarbonate resin, polymethyl methacrylate resin, polyethylene terephthalate resin, polyethersulfone resin, cellulose ester resin, benzocyclobutene resin, vinyl chloride resin, and acrylic resin.

[0090] When using a CNT film as the first and second components, the heat output of the heating element can be adjusted by adjusting the thickness of the CNT film, for example, by adjusting the number of CNT mesh layers when the CNT film is a CNT mesh laminate.

[0091] Besides its use as a heating element, the aforementioned composite material can also be used in: aerospace applications such as aircraft; footwear; sports and leisure applications such as fishing rods, golf clubs, and tennis rackets; heat dissipation materials; electrode plates; electromagnetic wave shielding components; electromagnetic wave absorbing sheets; antistatic plates; battery components; electronic components; and electronic devices such as laptops, tablets, and smartphone casings. Furthermore, the aforementioned composite material can also be used in building materials, bags, automobiles, and wind turbines.

[0092] In the aforementioned composite, the first and second components are bonded together by a CNT mesh without using a resin-containing adhesive. Therefore, in one embodiment, the composite maintains the electrical properties, etc., inherent in carbon materials.

[0093] The present invention has the following aspects. [1] A composite material having: The first component containing the first carbon material, The second component containing the second carbon material, and A network of carbon nanotubes located between the first component and the second component and respectively connected to the first component and the second component. [2] As described in [1], the carbon nanotube network is a carbon nanotube network obtained by pulling out multiple carbon nanotubes from a carbon nanotube forest or a stack of the carbon nanotube network. [3] The composite as described in [1] or [2], wherein the area weight of the carbon nanotube network is 0.00113–0.17 mg / cm³. 2 . [4] The composite as described in any one of [1] to [3], wherein the first carbon material and the second carbon material are carbon nanotubes, and the first component and the second component are carbon nanotube films. [5] The composite as described in any one of [1] to [4], wherein the carbon nanotube film, which is the first component, has a unit area weight of 0.0226 to 170 mg / cm³. 2 The carbon nanotube membrane, serving as the second component, has a unit weight of 0.0226–170 mg / cm³. 2 . [6] A method for manufacturing a composite, comprising: The process of preparing a first component comprising a first carbon material, a network of carbon nanotubes, and a second component comprising a second carbon material, and The process of bonding the first component and the second component together through the network of carbon nanotubes. [7] A composite obtained by bonding a first component containing a first carbon material to a second component containing a second carbon material through a network of carbon nanotubes. [8] A heating element comprising any one of [1] to [5] and [7]. [9] A network of carbon nanotubes for bonding a first component containing a first carbon material to a second component containing a second carbon material.

[10] An article containing carbon materials, which has the following characteristics: Components containing carbon material having a first region and a second region, and A network of carbon nanotubes located between the first region and the second region and connected to both the first region and the second region respectively. Example

[0103] The following describes the composite of the present disclosure in further detail based on the embodiments, but the composite of the present disclosure is not limited to these embodiments.

[0104] [Production Example 1] <Producing CNT Forest> Prepare a wafer with a catalyst for growing carbon nanotubes, and grow vertically aligned carbon nanotubes from this catalyst by chemical vapor deposition to fabricate a vertically aligned carbon nanotube forest that is vertically aligned with respect to the wafer. The carbon nanotubes constituting the carbon nanotube forest are multi-walled carbon nanotubes, each having an average length of 250 μm, an average diameter of 6-10 nm, a carbon purity of 99.8% or more, and a crystallinity (D / G ratio) of 0.6-0.8.

[0105] <Fabrication of CNT Network (1)> In the CNT forest formed on the catalyst substrate, pinch and pull out multiple CNTs located at the end with a picking tool to form a sheet. In this way, a single layer of CNT network (1) is fabricated. The size of the CNT network (1) is 1 cm in length, 2.5 cm in width, 2.5 cm in length, 1 cm in width, or 1 cm in length and 1 cm in width. The length of the CNT network refers to the length of the CNT network along the length direction of the CNT fiber, and the width of the CNT network refers to the length of the CNT network along the short side direction of the CNT fiber. The areal weight of the CNT network (1) is 0.0034 mg / cm 2 .

[0106] [Production Example 2] <Fabrication of CNT Film (1)> Fabricate a CNT forest in the same manner as in Production Example 1, pull out the CNT network, and then wind the CNT network around the circumference of a roller with a diameter of 800 mm for 50 turns. Next, cut and unwind the wound CNT network along the rotation axis direction of the roller to separate it from the roller. Thus, a CNT film (1) with 50 layers of CNT network laminated is obtained. After cutting the CNT film (1) into the required size, it is used. The size of the CNT film (1) is 10 cm in length, 2.5 cm in width, or 10 cm in length and 1 cm in width. The length of the CNT film refers to the length of the CNT film along the length direction of the CNT fiber, and the width of the CNT film refers to the length of the CNT film along the short side direction of the CNT fiber. The areal weight of the CNT film (1) is 0.17 mg / cm 2 .

[0107] [Production Example 3] <Fabrication of CNT Film (2)> Except for winding the CNT network around the circumference of the roller for 400 turns, in the same manner as in Production Example 2, a CNT film (2) with 400 layers of CNT network laminated is obtained. After cutting the CNT film (2) into the required size, it is used. The size of the CNT film (2) is 10 cm in length, 2.5 cm in width, or 10 cm in length and 1 cm in width. The areal weight of the CNT film (2) is 1.36 mg / cm2 .

[0108] [Example 1] Prepare a CNT mesh (1) with a length of 1 cm and a width of 2.5 cm, a CNT membrane (1) with a length of 10 cm and a width of 2.5 cm, and a CNT membrane (2) with a length of 10 cm and a width of 2.5 cm. Overlap the ends of the CNT membrane (1) and the CNT membrane (2) in the length direction, such that the length directions of each membrane are aligned and the overlapping area of ​​the two membranes when viewed from above is a region of 1 cm (length direction) × 2.5 cm (short side direction). At this time, in the above-mentioned overlapping area, the CNT mesh (1) is arranged between the CNT membrane (1) and the CNT membrane (2) in such a way that the length direction of the CNT fibers constituting the CNT mesh (1) is parallel to the length direction of the membrane. Next, by pressing the overlapping portion of the CNT membrane (1), CNT mesh (1), and CNT membrane (2) with your hand, the CNT membrane (1) and CNT membrane (2) are bonded together through the CNT mesh (1), thereby forming a composite (1). In the composite (1), the length direction of the CNT fibers constituting the CNT membranes (1) and (2) is parallel to the length direction of the CNT fibers constituting the CNT mesh (1).

[0109] [Example 2] A CNT fiber web (1) with a length of 2.5 cm and a width of 1 cm was prepared. The composite (2) was manufactured in the same manner as in Example 1, except that the CNT fiber web (1) was arranged between the CNT membranes (1) and (2) in the overlapping region such that the length direction of the CNT fibers constituting the CNT fiber web (1) was parallel to the short side direction of the membranes. In the composite (2), the length direction of the CNT fibers constituting the CNT membranes (1) and (2) was orthogonal to the length direction of the CNT fibers constituting the CNT web (1).

[0110] <Mechanical Property Evaluation> Using a tensile testing machine (manufactured by Shimadzu Corporation, Autograph AGS-X), the CNT films (1) and (2) in composites (1) or (2) were stretched in opposite directions at a tensile speed of 5 mm / min, and the loads at which the CNT films (1) and (2) peeled off, i.e., the maximum shear loads, were measured. The maximum shear load in composite (1) was 3.7 N. The maximum shear stress was calculated to be 14.8 kPa based on the maximum shear load. The maximum shear load in composite (2) was 2.4 N. The maximum shear stress was calculated to be 9.6 kPa based on the maximum shear load.

[0111] [Comparative Example 1] Except that CNT mesh (1) is not placed between CNT film (1) and CNT film (2) in the above-mentioned repeated area, CNT film (1) and CNT film (2) are overlapped in the same manner as in Example 1 or 2, and pressure is applied by pressing the overlapping part by hand. As a result, CNT film (1) and CNT film (2) do not stick together.

[0112] [Example 3] Prepare a CNT mesh (1) with a length of 1 cm and a width of 1 cm, a CNT membrane (1) with a length of 10 cm and a width of 1 cm, and a CNT membrane (2) with a length of 10 cm and a width of 1 cm. Overlap the ends of the CNT membrane (1) and the CNT membrane (2) in the length direction, such that the length directions of each membrane are aligned and the overlapping area of ​​the two membranes is 1 cm × 1 cm when the composite is viewed from above. At this time, in the above-mentioned overlapping area, the CNT mesh (1) is arranged between the CNT membrane (1) and the CNT membrane (2) in such a way that the length direction of the CNT fibers constituting the CNT mesh (1) is parallel to the length direction of the membrane. Next, by pressing the overlapping portion of the CNT membrane (1), CNT mesh (1), and CNT membrane (2) with your hand, the CNT membrane (1) and CNT membrane (2) are bonded together through the CNT mesh (1), thereby forming a composite (3). In the composite (3), the length direction of the CNT fibers constituting the CNT membranes (1) and (2) is parallel to the length direction of the CNT fibers constituting the CNT mesh (1).

[0113] <Electrical Characteristics Evaluation> For the composite (3), contact electrodes were placed at the ends of the CNT film (1) and the CNT film (2) that were not bonded to the CNT mesh (1) along their length, respectively. The resistance of the composite (3) was measured using an RG-7C manufactured by NAPSON Corporation, and the result was a resistance of 23.7 Ω. Thus, it can be confirmed that the CNT film (1) and the CNT film (2) are bonded and electrically connected through the CNT mesh (1).

[0114] [Example 4] <Manufacturing of the heating element> Except for changing the length and width of the CNT mesh to 1.5cm, the CNT mesh was manufactured in the same manner as in manufacturing example 1 (2). Except for changing the length and width of the CNT film to 1.5 cm, a CNT film with 400 layers of CNT mesh was manufactured in the same manner as in Manufacturing Example 3 (3). In addition, except for changing the length and width of the CNT film to 12 cm and 1.5 cm, a CNT film with 400 layers of CNT mesh was manufactured in the same manner as in Manufacturing Example 3 (4).

[0115] One end of the CNT membrane (4) along its length direction is overlapped with the CNT membrane (3) on one surface, such that the length directions of the CNT fibers constituting each membrane are aligned and the overlapping area of ​​the two membranes when viewed from above is a region of 1.5 cm × 1.5 cm. At this time, in the above-mentioned overlapping area, the CNT membrane (3) and the CNT membrane (4) are arranged such that the length direction of the CNT fibers constituting the CNT mesh (2) is parallel to the length direction of the CNT membrane (4). Next, by applying pressure to the overlapping portion of the CNT membrane (3), the CNT mesh (2) and the CNT membrane (4), the CNT membrane (3) and the CNT membrane (4) are bonded together through the CNT mesh (2).

[0116] In the same manner, the CNT membrane (3) is bonded to the other end of one surface of the CNT membrane (4) in the longitudinal direction and to both ends of the other surface of the CNT membrane (4) in the longitudinal direction via the CNT mesh (2). Thus, a composite (4) is obtained in which a total of four CNT films (3) are bonded to both sides of the CNT film (4). In the composite (4), the length direction of the CNT fibers constituting the CNT films (3) and (4) is parallel to the length direction of the CNT fibers constituting the CNT mesh (2). Figure 2 As shown, the composite (4) has a CNT mesh (2) and CNT membranes (3) to (4).

[0117] A CBZ resin film manufactured by U-PICA Corporation of Japan is laminated on the unbonded portion of the CNT film (3) in the CNT film (4), and the CNT film (3) is connected to an external power source to form a heating element (1).

[0118] <Evaluation of Heating Characteristics> When a voltage of 5V is applied to the heating element (1), the CNT film (4) heats up, and the resin film also heats up. When the temperature distribution of the resin film is observed using a Pocket2 manufactured by HIKMICRO, the highest temperature is 75.8℃. Symbol Explanation

[0119] 1…complex 10…First Component 20…Second component 30…CNT reticular formation 40...Substrate 42…CNT Forest 50…CNT nets pulled from the CNT forest 52…CNT fibers that make up the CNT mesh 60…rollers

Claims

1. A composite comprising: a first member comprising a first carbon material, a second member comprising a second carbon material, and a network of carbon nanotubes positioned between and in contact with the first member and the second member. The network of carbon nanotubes is a network of carbon nanotubes or a laminate of the network of carbon nanotubes obtained by pulling out a plurality of carbon nanotubes from a carbon nanotube forest. The first and second carbon materials are carbon nanotubes, and the first and second members are carbon nanotube films.

6. A method for producing a composite, comprising: a step of preparing a first member comprising a first carbon material, a network of carbon nanotubes, and a second member comprising a second carbon material, and a step of bonding the first member and the second member via the network of carbon nanotubes.

2. The complex of claim 1, wherein, 7. A composite obtained by bonding a first member comprising a first carbon material and a second member comprising a second carbon material via a network of carbon nanotubes.

3. The complex of claim 1, wherein, The weight per unit area of the network of carbon nanotubes is 0.00113 to 0.17 mg / cm 2 .

4. The complex of claim 1, wherein, 8. A heating element comprising the composite according to claim 1.

5. The complex of claim 4, wherein, The carbon nanotube film as the first member has a weight per unit area of 0.0226 to 170 mg / cm 2 The carbon nanotube film as the second member has a weight per unit area of 0.0226 to 170 mg / cm 2 .

9. A network of carbon nanotubes for bonding a first member comprising a first carbon material and a second member comprising a second carbon material.

10. An article comprising a carbon material, comprising: a member comprising a carbon material having a first region and a second region, and a network of carbon nanotubes positioned between and in contact with the first region and the second region. ​ ​ ​ ​ ​ ​ ​

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