JP7012412B2 - Method for manufacturing carbon nanotube composite wire, carbon nanotube-coated wire and carbon nanotube-coated wire - Google Patents

Description

The present invention relates to a carbon nanotube composite wire formed by bundling a carbon nanotube wire composed of a plurality of carbon nanotubes and a conductive wire, and a carbon nanotube-coated electric wire coated with the carbon nanotube composite wire. The present invention also relates to a method for manufacturing a carbon nanotube-coated electric wire.

Carbon nanotubes are materials having various properties and are expected to be applied to many fields.

For example, CNT is a three-dimensional network structure composed of a single layer of a tubular body having a network structure of a hexagonal lattice or multiple layers arranged substantially coaxially, and is lightweight, conductive, and heat conductive. Excellent in various properties such as properties and mechanical strength. However, it is not easy to convert CNTs into wire rods, and no technique for using CNTs as wire rods has been proposed.

In addition, when a single number of carbon nanotube aggregates formed by bundling a plurality of carbon nanotubes or a carbon nanotube wire rod formed by bundling a plurality of carbon nanotube aggregates is applied as a conductor for various purposes, the outside is used. In order to ensure the insulating property, a carbon nanotube-coated electric wire in which the carbon nanotube wire is coated with an insulating material is used. When connecting a carbon nanotube-coated electric wire, for example, the insulating coating layer at the longitudinal end of the carbon nanotube-coated electric wire is removed to expose the longitudinal end of the carbon nanotube wire, and this exposed portion is connected to an external terminal or the like. By doing so, the carbon nanotube-coated electric wire is electrically connected to the outside.

Conventionally, as a configuration for covering a wire rod, for example, a copper composite aluminum wire having an outer circumference of a reinforcing stranded wire composed of a plurality of organic wire rods containing carbon fiber as a reinforcing component and an outer periphery of a copper wire coated with aluminum is used. A low-loss stranded wire obtained by twisting a plurality of wires has been proposed (Patent Document 1).

Further, a twisted wire obtained by twisting a plurality of high tensile strength organic fibers subjected to metal plating treatment and a plurality of synthetic fibers or carbon fibers, and a plurality of high tensile strength organic fibers subjected to metal plating treatment. A twisted wire made by twisting a plurality of synthetic fibers or carbon fibers that have not been subjected to a metal plating treatment, or a plurality of high tensile strength organic fibers that have been subjected to a metal plating treatment are twisted on the outside of a copper wire. A stranded wire has been proposed (Patent Document 2).

Further, a composite coated copper wire having at least a central conductor made of copper or a copper alloy, a carbon composite plating film formed on the outer periphery of the center conductor, and a solderable plating film formed on the outermost layer is proposed. (Patent Document 3).

Further, a conductor having a metal layer on the outer periphery of a core wire made of a conductive single fiber and an insulating layer provided on the outer periphery of the conductor are provided, and the conductive single fiber contains 5% by mass or more of a conductive filler such as CNT. An insulated wire made of a composition containing less than% by mass has been proposed (Patent Document 4).

Further, as another conventional configuration, an insulated wire having a conductor made of a conductive fiber material and an insulating coating covering the outer periphery of the conductor has a spiral shape, and the conductor has higher flexibility than the insulating coating. A curl cord having an organic fiber whose outer periphery is covered with a metal layer or made of a carbon fiber has been proposed (Patent Document 5).

Jitsukaihei 2-22525 Gazette Japanese Unexamined Patent Publication No. 2008-130241 Japanese Unexamined Patent Publication No. 2007-42355 Japanese Unexamined Patent Publication No. 2017-191698 JP-A-2017-157538

Since the raw wire (single wire) of carbon nanotubes has low rigidity or self-supporting property, even if an insulating coating layer is provided on the outer periphery of the carbon nanotube wire rod or the carbon nanotube stranded wire, the self-supporting property of the carbon nanotube-coated electric wire is high. Still low. Further, when the carbon nanotube-coated electric wire is curved and wired or wound to be used as a coil, it is difficult to maintain its shape, so it is necessary to fix the carbon nanotube-coated electric wire to the outside. Therefore, the workability at the time of manufacturing or mounting the carbon nanotube-coated electric wire is poor.

In Patent Document 1, since the copper-aluminum composite wire is used as the conductor of the wire and not the CNT wire is used as the conductor, the self-supporting property is high and the above-mentioned problems do not occur.

Further, in Patent Document 2, the conductor is mainly composed of high tensile strength organic fiber subjected to metal plating treatment, and not the conductor is mainly CNT wire. Therefore, as in Patent Document 1, the above is described. Such a problem does not occur.

In Patent Document 3, copper or a copper alloy is mainly used as a conductor, and CNT wire is not mainly used as a conductor. Therefore, as in Cited Document 1, the above-mentioned problems do not occur.

In Patent Document 4, the conductive single fiber containing CNT as a conductive filler and the metal layer provided on the outer periphery thereof are used as a conductor, and the CNT wire is not used as a conductor. Similarly, the above-mentioned problems do not occur.

Further, in Patent Document 5, the outer periphery of the organic fiber is covered with a metal layer, or a wire made of carbon fiber is used as a conductor, and the CNT wire is not used as a conductor. Similarly, the above-mentioned problems do not occur.

An object of the present invention is to provide a carbon nanotube composite wire, a carbon nanotube-coated electric wire, and a method for manufacturing a carbon nanotube-coated electric wire, which can be self-supporting and improve workability.

In order to achieve the above object, the carbon nanotube composite wire of the present invention is formed from a single number of carbon nanotube aggregates composed of a plurality of carbon nanotubes, or a plurality of the carbon nanotube aggregates formed by bundling the carbon nanotube aggregates. The ratio of the cross-sectional area of the plurality of carbon nanotubes to the cross-sectional area of the carbon nanotube composite wire is 65. It is characterized by being% or more and less than 95%.

The plurality of carbon nanotube wires and the one or more conductive wires may be twisted and configured.

Further, the one or more conductive wires may be made of metal.

The metal is preferably copper or a copper alloy.

The circle-equivalent diameter of the carbon nanotube composite wire may be 50 μm or more and 3 mm or less.

The ratio of the cross-sectional area of the plurality of carbon nanotubes to the cross-sectional area of the carbon nanotube composite wire is preferably 65% or more and 90% or less.

It is more preferable that the ratio of the cross-sectional area of the plurality of carbon nanotubes to the cross-sectional area of the carbon nanotube composite wire is 75% or more and 85% or less.

In the cross section of the carbon nanotube composite wire, the plurality of carbon nanotube wires are arranged in the central portion of the carbon nanotube composite wire, and the plurality of conductive wires are arranged in the outer peripheral portion of the plurality of carbon nanotube wires. You may.

Further, in the cross section of the carbon nanotube composite wire, the plurality of carbon nanotube wires and the plurality of conductive members may be randomly arranged.

Further, in the cross section of the carbon nanotube composite wire, the one or more conductive wires are arranged in the central portion of the carbon nanotube composite wire, and the plurality of carbon nanotube wires is the one or more conductive wires. It may be arranged on the outer peripheral portion.

In order to achieve the above object, the carbon nanotube-coated electric wire of the present invention is formed from a single number of carbon nanotube aggregates composed of a plurality of carbon nanotubes, or a plurality of the carbon nanotube aggregates formed by bundling them. The carbon nanotube composite wire having the carbon nanotube wire rod, one or a plurality of conductive wires having higher rigidity than the plurality of carbon nanotube wire rods, and an insulating coating layer covering the carbon nanotube composite wire. The ratio of the cross-sectional area of the plurality of carbon nanotubes to the cross-sectional area of the carbon nanotube composite wire is 65% or more and less than 95%.

In order to achieve the above object, the method for manufacturing a carbon nanotube-coated electric wire of the present invention is formed from a single number of carbon nanotube aggregates composed of a plurality of carbon nanotubes, or formed by bundling a plurality of the carbon nanotube aggregates. A carbon nanotube composite wire is formed by bundling a plurality of the carbon nanotube wires and one or a plurality of conductive wires having higher rigidity than the carbon nanotube wires. Having a step of making the ratio of the cross-sectional area of the plurality of carbon nanotubes to the cross-sectional area of the nanotube composite wire 65% or more and less than 95%, and a step of forming an insulating coating layer covering the carbon nanotube composite wire. It is a feature.

According to the present invention, the carbon nanotube composite wire comprises one or a plurality of conductive wires having higher rigidity than the plurality of carbon nanotube wire rods, and the cross-sectional area of the plurality of carbon nanotubes relative to the cross-sectional area of the carbon nanotube composite wire. Since the ratio is 65% or more, the rigidity of the carbon nanotube composite wire as a whole becomes high, and it is possible to give independence. Therefore, workability can be improved at the time of manufacturing or mounting the carbon nanotube composite wire or the carbon nanotube-coated electric wire.

It is sectional drawing which shows the structure of the carbon nanotube-coated electric wire which concerns on embodiment of this invention. It is a perspective view which shows the modification of the carbon nanotube-coated electric wire of FIG. (A) and (b) are sectional views showing another modification of the carbon nanotube-coated electric wire of FIG. It is a flowchart which shows an example of the manufacturing method of the carbon nanotube-coated electric wire of FIG. It is a figure explaining the test method for evaluating the independence of the carbon nanotube composite wire of FIG. 1.

Hereinafter, the carbon nanotube composite wire and the carbon nanotube-coated electric wire according to the embodiment of the present invention will be described with reference to the drawings.

[Structure of carbon nanotube-coated wire]
As shown in FIG. 1, the carbon nanotube-coated electric wire (hereinafter, also referred to as “CNT-coated electric wire”) 1 according to the embodiment of the present invention is a carbon nanotube composite wire (hereinafter, also referred to as “CNT composite wire”) 2. And an insulating coating layer 21 that covers the CNT composite wire 2. That is, the insulating coating layer 21 is formed along the longitudinal direction of the CNT composite wire 2. In the CNT-coated electric wire 1, the entire outer peripheral surface of the CNT composite wire 2 is covered with the insulating coating layer 21. Further, in the CNT-coated electric wire 1, the insulating coating layer 21 is in direct contact with the outer peripheral surface of the CNT composite wire 2.

The CNT composite wire 2 includes a plurality of carbon nanotube wires (hereinafter, also referred to as “CNT wires”) 10, 10, ..., And a plurality of conductive wires having higher rigidity than the plurality of carbon nanotube wires 10, 10, .... It is provided with sex wire rods 12, 12, .... The CNT composite wire 2 is, for example, a CNT composite stranded wire formed by twisting a plurality of CNT wires 10, 10, ... And a plurality of conductive wires 12, 12, .... By forming the CNT composite wire 2 in the form of a stranded wire obtained by twisting a plurality of CNT wire rods 10 which are strands (single wire), the diameter equivalent to a circle and the cross-sectional area of the CNT composite wire 2 can be appropriately adjusted. The diameter corresponding to the circle of the CNT composite wire 2 is not particularly limited, but is, for example, 50 μm or more and 3 mm or less. The diameter equivalent to the circle was calculated from the average value of the distance of the line segment drawn so as to pass through the center measured at three points in the circumferential direction.

The CNT composite wire 2 may include a state in which the longitudinal direction of the CNT wire rod 10 and the longitudinal direction of the CNT composite wire 2 are the same or substantially the same. That is, the CNT composite wire 2 may include those in which a plurality of CNT wires 10 are bundled in an untwisted state, and the CNT composite wire 2 may be bundled in a state in which a plurality of conductive wires 12 are not twisted. It may include those that are present.

The plurality of CNT wires 10, 10, ... And the plurality of conductive wires 12, 12, ... Constituting the CNT composite wire 2 can be arranged in several patterns. For example, in FIG. 1, in the cross section of the CNT composite wire 2, a plurality of CNT wires 10, 10, ... Are arranged in the central portion of the CNT composite wire 2, and the plurality of conductive wires 12, 12, ... Is arranged on the outer peripheral portion of the plurality of CNT wires 10, 10, .... In this case, the plurality of conductive wires 12, 12, ... Are arranged over the entire circumferential direction so as to cover the entire outer peripheral portion of the plurality of CNT wires 10, 10, ... For example.

The CNT wire rod 10 is formed from a single number of carbon nanotube aggregates (hereinafter, also referred to as “CNT aggregates”) 11 composed of a plurality of CNTs 11a, 11a, ..., Or a bundle of a plurality of CNTs. In FIG. 1, the CNT wire rod 10 is formed by bundling a plurality of CNT aggregates 11, 11, .... Here, the CNT wire rod means a CNT wire rod having a CNT ratio of 90% by mass or more. In the calculation of the CNT ratio in the CNT wire, the mass of plating and dopant is excluded. The longitudinal direction of the CNT aggregate 11 forms the longitudinal direction of the CNT wire rod 10. Therefore, the CNT aggregate 11 is linear. The plurality of CNT aggregates 11, 11, ... In the CNT wire rod 10 are arranged so that their major axis directions are substantially aligned. Therefore, the plurality of CNT aggregates 11, 11, ... In the CNT wire 10 are oriented. The diameter corresponding to the circle of the CNT wire rod 10 which is a strand is not particularly limited, but is, for example, 5 μm or more and 200 μm or less. By setting the equivalent circle diameter of the CNT wire 10 to a value within the above range, it is possible to form the CNT composite wire 2 having a fine wire diameter that is difficult to form with a metal wire or carbon fiber.

The CNT aggregate 11 is a bundle of CNTs 11a having a layer structure of one or more layers. The longitudinal direction of the CNT 11a forms the longitudinal direction of the CNT aggregate 11. The plurality of CNTs 11a, 11a, ... In the CNT aggregate 11 are arranged so that their major axis directions are substantially aligned. Therefore, the plurality of CNTs 11a, 11a, ... In the CNT aggregate 11 are oriented. The circle-equivalent diameter of the CNT aggregate 11 is, for example, 20 nm or more and 1000 nm or less, and more typically 20 nm or more and 80 nm or less. The width dimension of the outermost layer of the CNT 11a is, for example, 1.0 nm or more and 20 nm or less.

The CNTs 11a constituting the CNT aggregate 11 are tubular bodies having a single-walled structure or a multi-walled structure, and are called SWNTs (single-walled nanotubes) and MWNTs (multi-walled nanotubes), respectively. The CNT aggregate 11 may also include a CNT having a layer structure of three or more layers or a CNT having a layer structure of a single layer structure, or a CNT having a layer structure of three or more layers or a single layer structure. It may be formed from CNT having a layered structure.

The CNT 11a having a two-layer structure is a three-dimensional network structure in which two tubular bodies having a network structure of a hexagonal lattice are arranged substantially coaxially, and is called a DWNT (Double-walled nanotube). The hexagonal lattice, which is a constituent unit, is a six-membered ring in which carbon atoms are arranged at its vertices, and these are continuously bonded adjacent to other six-membered rings.

Next, the conductive wire rod 12 constituting the CNT composite wire 2 will be described.
The plurality of conductive wires 12, 12, ... Are each formed of a single wire or a bundle of a plurality of strands, and are made of a material different from that of the plurality of CNT wires 10, 10, .... There is. The plurality of conductive wires 12, 12, ... Are composed of, for example, metal. The metal refers to a simple substance of a metal or an alloy containing the metal as a main component, and is, for example, copper or a copper alloy. Since the plurality of conductive wires 12, 12, ... Are made of metal, the conductivity of the CNT composite wire 2 can be improved. Further, as shown in FIG. 1, in a configuration in which a plurality of conductive wires 12, 12, ... Are arranged on the outer peripheral portions of the plurality of CNT wires 10, 10, ..., The plurality of conductive wires are arranged. Since 12, 12, ... Are made of copper or a copper alloy, it is possible to prevent deformation of the CNT composite wire 2 due to an external force such as compression. Further, when forming the insulating coating layer 21, even when a covering material having poor compatibility with CNT and difficult to cover the CNT composite wire 2 is used from the viewpoint of adhesion, a metal such as copper or a copper alloy is used. If the covering material is compatible with the above, the CNT composite wire 2 can be covered with the covering material.

The conductive wire rod 12 is a wire (single wire) made of one conductor, but the conductive wire rod 12 may be in the state of a stranded wire obtained by twisting a plurality of conductive wire rods 12. By forming the conductive wire rod 12 in the form of a stranded wire, the diameter equivalent to a circle and the cross-sectional area of the conductive wire rod 12 can be appropriately adjusted. The diameter equivalent to the circle of the conductive wire rod 12 is not particularly limited, but is, for example, 10 μm or more and 1 mm or less.

In the CNT composite line 2 configured as described above, the ratio of the cross-sectional area of the plurality of CNTs 11a, 11a, ... To the cross-sectional area of the CNT composite line 2 is 65% or more and less than 95%, preferably 65%. It is 90% or more, more preferably 75% or more and 85% or less. By setting the ratio of the cross-sectional areas of the plurality of CNTs 11a, 11a, ... To the cross-sectional area of the CNT composite line 2 to 65% or more and less than 95%, the CNT composite line 2 can be made rigid. Further, by setting the ratio of the cross-sectional areas of the plurality of CNTs 11a, 11a, ... To the cross-sectional area of the CNT composite wire 2 to 65% or more and 90% or less, the CNT composite wire 2 having light weight and high rigidity is realized. be able to. Further, by setting the ratio of the cross-sectional areas of the plurality of CNTs 11a, 11a, ... To the cross-sectional area of the CNT composite line 2 to 75% or more and 85% or less, the CNT composite line in which light weight and high rigidity are balanced at a high level. 2 can be realized.

Next, the insulating coating layer 21 that covers the outer peripheral portion of the CNT composite wire 2 will be described.

As the material of the insulating coating layer 21, a material used for the insulating coating layer of a coated electric wire using a metal as a core wire can be used, and examples thereof include a thermoplastic resin and a thermosetting resin. Examples of the thermoplastic resin include polytetrafluoroethylene (PTFE), polyethylene, polypropylene, polyacetal, polystyrene, polyethylene terephthalate, polybutylene terephthalate, polyphenylene sulfide, polyether ether ketone, polycarbonate, polyamide, polyvinyl chloride, and polymethylmethacrylate. , Polyethylene and the like. Moreover, as a thermosetting resin, for example, a polyimide, a phenol resin and the like can be mentioned. These may be used alone or may be used by appropriately mixing two or more kinds.

When the CNT-coated electric wire 1 is a high-voltage electric wire, polyethylene and polyvinyl chloride are preferable as the thermoplastic resin, and cross-linked polyethylene and soft polyvinyl chloride are particularly preferable.

As shown in FIG. 1, the insulating coating layer 21 may be a single layer, or may be two or more layers instead. Further, if necessary, a layer of a thermosetting resin may be further provided on the insulating coating layer 21. Further, the thermosetting resin may contain a filler having a fiber shape or a particle shape.

The CNT composite wire 2 of FIG. 1 has a configuration in which a plurality of conductive wires 12, 12, ... Are arranged on the outer peripheral portion of the plurality of CNT wires 10, 10, .... As shown in 2, in the cross section of the CNT composite wire 2, a plurality of CNT wires 10, 10, ... And a plurality of conductive members 12, 12, ... Are randomly arranged. It is also good.

Further, as shown in FIG. 3A, in the cross section of the CNT composite wire 2, the conductive wire rod 12 is arranged at the center of the CNT composite wire 2, and the plurality of CNT wire rods 10, 10, ... The configuration may be arranged on the outer peripheral portion of the conductive wire rod 12. In this case, the plurality of CNT wires 10, 10, ... Are arranged over the entire circumference of the conductive wire rod 12, for example, so as to cover the entire outer peripheral portion of the conductive wire rod 12. Further, as shown in FIG. 3B, in the cross section of the CNT composite wire 2, a single conductive wire rod 12 is arranged in the central portion of the CNT composite wire 2, and a plurality of CNT wire rods 10, 10, ... However, it may be configured to be arranged on the outer peripheral portion of the single conductive wire rod 12. In this case, the plurality of CNT wires 10, 10, ... Are arranged over the entire circumference in the circumferential direction so as to cover the entire outer peripheral portion of the single conductive wire rod 12.

[Manufacturing method of carbon nanotube-coated electric wire]
Next, an example of a method for manufacturing the CNT-coated electric wire 1 according to the present embodiment will be described with reference to FIG. First, a CNT wire rod that manufactures CNT11a and is formed from a singular number of CNT aggregates 11 composed of a plurality of CNTs 11a, 11a, ... Or by bundling a plurality of CNT aggregates 11, 11, ... 10 is produced (step S1).

The CNT11a can be produced by a method such as a floating catalyst method (Patent No. 5819888) or a substrate method (Patent No. 5590603). The strands of the CNT wire 10 are, for example, dry spinning (Patent No. 5819888, Patent No. 5990202, Patent No. 5350635), wet spinning (Patent No. 5135620, Patent No. 5131571, Patent No. 5288359), liquid crystal spinning. It can be manufactured according to (Special Table 2014-530964).

At this time, the orientation of the CNTs constituting the CNT wire rod 10, the orientation of the CNTs constituting the CNT aggregate, or the density of the CNT aggregates 11 and CNT11a is determined by, for example, spinning such as dry spinning, wet spinning, and liquid crystal spinning. It can be adjusted by appropriately selecting the method and the spinning conditions of the spinning method.

Next, a plurality of CNT wires 10 and one or a plurality of conductive wires 12 having higher rigidity than the plurality of CNT wires 10, 10, ... Are bundled to form a CNT composite wire 2, and the CNT composite wire 2 is formed. The ratio of the cross-sectional area of the plurality of CNTs 11a, 11a, ... To the cross-sectional area of is 65% or more and less than 95% (step S2).

When the CNT composite wire 2 is a CNT composite stranded wire formed by twisting a plurality of CNT wires 10, 10, ... And a plurality of conductive wires 12, 12, ..., For example, the CNT composite wire 2. The wire diameter and number of the CNT wire 10 and the wire diameter and number of the conductive wire 12 are set so that the ratio of the cross-sectional area of the plurality of CNTs 11a, 11a, ... To the cross-sectional area of the wire 2 is 65% or more. decide. Then, after deciding the arrangement of the plurality of CNT wires 10, 10, ... And the plurality of conductive wires 12, 12, ..., the plurality of CNT wires 10 and the plurality of conductive wires 12 are placed in the S direction. Alternatively, the CNT composite wire 2 is formed by twisting in the Z direction. The CNT composite stranded wire can be manufactured, for example, by fixing both ends of the created plurality of CNT wires 10, 10, ... To two substrates arranged facing each other and rotating one of the facing substrates. can.

When the CNT composite wire 2 is composed of a plurality of CNT wires 10, 10, ... And one conductive wire 12, 12, ..., for example, the strands of the CNT wire 10 based on the above ratio. The diameter and number, and the wire diameter and cross-sectional area of the conductive wire rod 12 are determined, and a plurality of CNT wire rods 10 are twisted in the S direction or the Z direction on the outer peripheral portion of the conductive wire rod 12 to form the CNT composite wire 2. do.

Next, the insulating coating layer 21 that covers the CNT composite wire 2 is formed (step S3). At this time, the insulating coating layer 21 is formed over the entire longitudinal direction of the CNT composite wire 2 so as to cover the entire outer peripheral portion of the CNT composite wire 2. As a method of forming the insulating coating layer 21, a method of coating the insulating coating layer on the core wire of aluminum or copper can be used. For example, the thermoplastic resin which is the raw material of the insulating coating layer 21 is melted and the CNT composite wire 2 is formed. Examples thereof include a method of extruding and covering the periphery, and a method of applying the coating around the CNT composite wire 2. By going through the above steps, the CNT-coated electric wire 1 according to the present embodiment is manufactured.

The CNT-coated electric wire 1 according to the present embodiment can be used as a general electric wire such as a wire harness, and a cable may be manufactured from the general electric wire using the CNT-coated electric wire 1.

As described above, according to the present embodiment, the CNT composite wire 2 includes one or a plurality of conductive wire rods 12 having higher rigidity than the plurality of CNT wire rods 10, and a plurality of CNT composite wires 2 with respect to the cross-sectional area of the CNT composite wire 2. Since the ratio of the cross-sectional area of the CNTs 11a, 11a, ... Of the CNTs 11a, 11a, ... Therefore, workability can be improved at the time of manufacturing or mounting the CNT composite wire 2 or the CNT-coated electric wire 1.

Next, examples of the present invention will be described, but the present invention is not limited to the following examples as long as the gist of the present invention is not exceeded.

(Regarding Examples 1 to 6 and Comparative Examples 1 to 4)
Wire (single wire) of CNT wire by the dry spinning method (Patent No. 5819888) or the wet spinning method (Patent No. 5135620, Patent No. 5315571, Patent No. 5288359) in which CNTs produced by the floating catalyst method are directly spun. After that, the CNT wires were bundled or twisted to obtain a CNT wire having a diameter equivalent to a circle of 1 mm to 2 mm.

Next, the ratio of the cross-sectional area of the plurality of CNTs to the cross-sectional area of the CNT composite wire is adjusted so as to be the value shown in Table 1, and further, the CNT wire and the conductivity are adjusted so as to have a twisted structure as shown in Table 1. A copper wire, which is a wire, is arranged, and then a plurality of the above CNT wires and one or a plurality of copper wires are bundled, and the bundled CNT wire and the copper wire are twisted so as to have a predetermined number of turns, and the CNT composite wire is used. I got a test line that is.

Next, the following measurements and evaluations were performed on the test lines prepared as described above.

(A) Evaluation of independence As a method for evaluating independence, a test device 100 as shown in FIG. 5 was used, and the wire diameter of the obtained test line 101 was extended laterally from the test device 100 by D (mm). When the extension length of the test line 101 is L ⁽ mm), the longitudinal end of the test line 101 is placed on the mounting surface 100a of the test device 100 so that L2 / D becomes 75,000. The original position of the longitudinal end 101a of the test line 101 that was fixed in the state and hung down due to its own weight (position when it is assumed that the test line 101 does not bend with reference to the height position of the mounting surface 100a). When the distance X from the distance X was (cm), X / L was measured as the degree of deflection by its own weight. When X / L is less than 0.05, it is regarded as extremely good "⊚", when it is 0.05 or more and less than 0.1, it is regarded as good "〇", and when it is 0.1 or more, it is regarded as defective "x".

(B) Resistance evaluation A CNT wire was connected to a resistance measuring machine (manufactured by Caseley Co., Ltd., device name "DMM2000"), and resistance was measured by the 4-terminal method. The volume resistivity was calculated based on the formula of r = RA / L (R: resistance, A: cross-sectional area of CNT stranded wire, L: measured length). Very good when the volume resistivity is less than 2 × 10 ⁴ Ωcm “◎”, good when it is 2.0 × 10 ⁴ Ω ・ cm or more and less than 5.0 × 10 ⁴ Ω ・ cm “〇”, 5 When it was 0.0 × 10 ⁴ Ω · cm or more, it was regarded as a defective “×”.

(C) Density evaluation The density of the test line was measured by dividing the mass per unit by the cross-sectional area and length measured from the microscope. When the density is less than 3 g / cm ³ , it is extremely good "◎", when it is 3 g / cm ³ or more and less than 5 g / cm ³ , it is good "○", and when it is 5 g / cm ³ or more, it is bad "x". did.

The results of each of the above measurements and evaluations of the CNT composite line are shown in Table 1 below.

As shown in Table 1, in Example 1, in a structure in which a plurality of CNT wires are arranged in the central portion of the CNT composite wire and a plurality of copper wires are arranged in the outer peripheral portion, the ratio of the CNT cross-sectional area to the cross-sectional area of the CNT composite wire is It was 90%, the self-weight deflection X / L was 0.06, and the independence was good. The volume resistivity of the CNT composite wire was 2.1 × 10 ⁴ Ω · cm, which was good. Furthermore, the density of the CNT composite wire was as light as 2.5 g / cm ³ , which was extremely good.

In Example 2, the ratio of the CNT cross-sectional area to the cross-sectional area of the CNT composite line is 85%, the self-weight deflection X / L is 0.04, and the volume resistivity of the CNT composite line is 1.9 × 10 ⁴ Ω · cm. The density was 2.8 g / cm ³ , and the independence, resistivity and density were all extremely good.

In Example 3, the ratio of the CNT cross-sectional area to the cross-sectional area of the CNT composite wire is 75%, the self-weight deflection X / L is 0.03, and the volume resistivity of the CNT composite wire is 1.5 × 10 ⁴ Ω · cm. The density was 3.6, and both independence and resistance were extremely good. The density of the CNT composite wire was 3.6 g / cm ³ , which was good.

In Example 4, the ratio of the CNT cross-sectional area to the cross-sectional area of the CNT composite wire is 65%, the weight deflection X / L is 0.02, and the volume resistivity of the CNT composite wire is 1.4 × 10 ⁴ Ω · cm. There was, and both independence and resistance were extremely good. The density of the CNT composite wire was 4.3 g / cm ³ , which was good.

In Example 5, in a structure in which a plurality of CNT wires and a plurality of copper wires are randomly arranged, the ratio of the CNT cross-sectional area to the cross-sectional area of the CNT composite wire is 85%, the self-weight deflection X / L is 0.04, and the CNT composite. The volume resistivity of the wire was 1.9 × 10 ⁴ Ω · cm, the density was 2.8 g / cm ³ , and the independence, resistance and density were extremely good.

In Example 6, in a structure in which one copper wire is arranged in the central portion of the CNT composite wire and a plurality of CNT wires are arranged in the outer peripheral portion, the ratio of the CNT cross-sectional area to the cross-sectional area of the CNT composite wire is 85%, and the degree of self-weight deflection. The X / L is 0.04, the volume resistivity of the CNT composite wire is 1.9 × 10 ⁴ Ω · cm, and the density is 2.9 g / cm ³ , and the independence, resistance and density are all extremely good. rice field.

On the other hand, in Comparative Example 1, in the structure in which a plurality of CNT wires are arranged in the central portion of the CNT composite wire and the plurality of copper wires are arranged in the outer peripheral portion, the ratio of the CNT cross-sectional area to the cross-sectional area of the CNT composite wire is 55%. The density of the CNT composite wire was 5.1 g / cm ³ , which was poor.

Further, in Comparative Example 2, the ratio of the CNT cross-sectional area to the cross-sectional area of the NT composite line was 95%, the self-weight deflection degree X / L was 0.12, and the independence was inferior.

In Comparative Example 3, in a structure in which a plurality of CNT wires and a plurality of copper wires are randomly arranged, the ratio of the CNT cross-sectional area to the cross-sectional area of the CNT composite wire is 95%, and the self-weight deflection X / L is 0.14. Independence was inferior.

In Comparative Example 4, in the structure in which one copper wire is arranged in the central portion of the CNT composite wire and a plurality of CNT wires are arranged in the outer peripheral portion, the ratio of the CNT cross-sectional area to the cross-sectional area of the CNT composite wire is 95%, and its own weight. The degree of deflection X / L was 0.15, and the independence was inferior.

1 Carbon nanotube-coated wire (CNT-coated wire)
2 Carbon nanotube composite wire (CNT composite wire)
10 Carbon nanotube wire rod (CNT wire rod)
11 Carbon nanotube aggregate (CNT aggregate)
11a Carbon nanotube (CNT)
12 Conductive wire 21 Insulation coating layer 100 Test device 100a Mounting surface 101 Test wire 101a Longitudinal end

Claims (9)

A single number of carbon nanotube aggregates composed of a plurality of carbon nanotubes, or a plurality of carbon nanotube wires formed by bundling the plurality of carbon nanotube aggregates.
One or more conductive wires having higher rigidity than the plurality of carbon nanotube wires,
It is a carbon nanotube composite wire equipped with
The ratio of the cross-sectional area of the plurality of carbon nanotubes to the cross-sectional area of the carbon nanotube composite wire is 75% or more and 85% or less .
A carbon nanotube composite wire, wherein the one or more conductive wires are made of a metal . The carbon nanotube composite wire according to claim 1, wherein the plurality of carbon nanotube wires and the one or a plurality of conductive wires are twisted together. The carbon nanotube composite wire according to claim 1 or 2 , wherein the metal is copper or a copper alloy. The carbon nanotube composite wire according to any one of claims 1 to 3 , wherein the carbon nanotube composite wire has a circle-equivalent diameter of 50 μm or more and 3 mm or less. In the cross section of the carbon nanotube composite wire, the plurality of carbon nanotube wires are arranged in the central portion of the carbon nanotube composite wire.
The carbon nanotube composite wire according to any one of claims 1 to 4 , wherein the plurality of conductive wires are arranged on the outer peripheral portion of the plurality of carbon nanotube wires. The carbon nanotube composite wire according to any one of claims 1 to 4, wherein the plurality of carbon nanotube wires and the plurality of conductive wires are randomly arranged in a cross section of the carbon nanotube composite wire. In the cross section of the carbon nanotube composite wire, the one or more conductive wires are arranged in the central portion of the carbon nanotube composite wire.
The carbon nanotube composite wire according to any one of claims 1 to 4 , wherein the plurality of carbon nanotube wires are arranged on the outer peripheral portion of the one or the plurality of conductive wires. The rigidity is higher than that of a plurality of carbon nanotube wires formed from a single carbon nanotube aggregate composed of a plurality of carbon nanotubes or by bundling the plurality of carbon nanotube aggregates, and the plurality of carbon nanotube wires. A carbon nanotube composite wire having one or more conductive wires and a carbon nanotube composite wire,
The insulating coating layer that covers the carbon nanotube composite wire and
Equipped with
The ratio of the cross-sectional area of the plurality of carbon nanotubes to the cross-sectional area of the carbon nanotube composite wire is 75% or more and 85% or less .
A carbon nanotube-coated electric wire, wherein the one or a plurality of conductive wires are made of a metal . A step of producing a carbon nanotube wire rod formed from a single carbon nanotube aggregate composed of a plurality of carbon nanotubes or by bundling the plurality of carbon nanotube aggregates.
A carbon nanotube composite wire is formed by bundling a plurality of the carbon nanotube wires and one or a plurality of conductive wires having higher rigidity than the carbon nanotube wires, and the plurality of the carbon nanotube composite wires with respect to the cross-sectional area of the carbon nanotube composite wires. The process of making the ratio of the cross-sectional area of carbon nanotubes 75% or more and 85% or less , and
The step of forming an insulating coating layer covering the carbon nanotube composite wire, and
Have,
A method for manufacturing a carbon nanotube-coated electric wire, wherein the one or a plurality of conductive wires are made of a metal .

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