KR20090084677A - Cable and methods for making the same - Google Patents

Abstract

A cable is provided to ensure excellent conductivity, mechanical strength, relatively light weight and relatively small diameter, and to reduce manufacturing costs. A cable(10) comprises at least one cable core(110); at least one insulating layer(120) coating the cable core; a shield layer(130) coating the insulating layer; and a protective layer(140) coating the shield layer. The cable core comprises a plurality of carbon nanotubes and conductive materials. A plurality of carbon nanotubes and conductive materials comprise at least one composite carbon nanotube wire.

Description

Cable and its manufacturing method {CABLE AND METHODS FOR MAKING THE SAME}

The present invention relates to a cable and a method of manufacturing the same, and more particularly to a cable and a method of manufacturing the carbon nanotubes.

Cable is a signal transmission medium that is commonly used in the electronics industry. Micro cables are widely used in the IT industry, medical devices, and space equipment. In a conventional cable, two conductors are provided inside. The inner conductor transmits an electrical signal, and the outer conductor shields the transmitted electrical signal to prevent the electrical signal from being lost. Because of this, the cable has low loss to high frequency, strong shielding and anti-jamming capability, and wide frequency bandwidth ["Electromagnetic Shielding of High-Voltage Cables" {M. De Wulf, P. Wouters et. Al., Journal of Magnetism and Magnetic Materials, 316, e908-e901 (2007)}.

In general, in a cable, a cable core which is an inner conductor sequentially from the inside, an insulating layer covering the surface of the cable core, a shield layer which is an outer conductor covering the insulating layer, and a protective layer covering the shield layer are provided. Is installed. The cable core transmits an electrical signal and the material is mainly copper (Cu), aluminum (Al) or copper-zinc (Cu-Zn) alloy. The shield layer is generally formed by knitting a metal wire or by coating a metal thin film on the surface of the insulating layer. The shield layer shields electromagnetic interference or interference of external signals.

The biggest problem in the cable core formed by the metal material is that a skin effect occurs when the alternating current is transmitted through the metal conductor. The skin effect reduces the effective cross sectional area through which current flows in the metal conductor. For this reason, the effective resistance value of the metal conductor is increased, so that the transmission efficiency of the cable may be reduced or the transmission signal may be lost. In addition, cables having a metallic material as a core and a shield layer have low strength, a large mass and a diameter, and therefore are not applicable to special areas such as aerospace, space facilities, ultra-fine cables, and the like.

Carbon nanotubes are a new type of one-dimensional nanomaterials with excellent conductivity, high tensile strength and high thermal stability. Carbon nanotubes show a very wide foreground in the field of boundary sciences such as materials science, chemistry and physics. Currently, composite materials formed by mixing carbon nanobubbles and metals are used as cable cores. However, the skin effect mentioned above still exists because the carbon nanotubes are disorderedly dispersed in the metal. In the conventional method for producing a cable including carbon nanotubes, a small amount of carbon nanotubes and metal are mixed by a method such as vacuum melting, vacuum sintering, or vacuum thermocompression, so that the manufacturing method is complicated. .

It is an object of the present invention to provide a cable and a method of manufacturing the cable having excellent conductivity, excellent mechanical strength, relatively light mass and relatively small diameter, simple manufacturing method, low manufacturing cost, and scaleable production.

A cable according to the present invention for achieving the above object includes at least one cable core, at least one insulating layer, at least one shield layer, and one protective layer. The insulating layer covers an outer surface of the cable core; The shield layer covers an outer surface of the insulating layer; The protective layer covers the outer surface of the shield layer. The cable core includes a conductive material and a plurality of carbon nanotubes. The plurality of carbon nanotubes and the conductive material constitute at least one composite carbon nanotube wire. The plurality of carbon nanotubes are arranged in order along the axial direction of the cable core among the composite carbon nanotube wires. At least one conductive material layer is formed on the outer surface of each carbon nanotube.

The cable according to the present invention further comprises at least one cable core, at least one insulating layer, at least one shield layer, and one protective layer. The insulating layer covers an outer surface of the cable core; The shield layer covers an outer surface of the insulating layer; The protective layer covers the outer surface of the shield layer. The cable core includes a conductive material and a plurality of carbon nanotubes. The plurality of carbon nanotubes in the cable core constitute at least one carbon nanotube linear structure. The plurality of carbon nanotubes are arranged in order along the axial direction of the cable core among the carbon nanotube linear structures. At least one conductive material layer is formed on the outer surface of the carbon nanotube linear structure.

In addition, the method of manufacturing a cable according to the present invention comprises the steps of providing at least one carbon nanotube structure; Forming a cable core by forming at least one conductive material layer on the at least one carbon nanotube structure; Forming at least one insulating layer on an outer surface of the cable core; Forming at least one shield layer on an outer surface of the insulating layer; And forming a protective layer of one layer on an outer surface of the shield layer.

The cable according to the present invention and its manufacturing method has the following advantages.

First, because the carbon nanotubes are arranged in order along the axial direction of the cable core in the cable, the cable comprising the carbon nanotubes has excellent conductivity.

Second, because carbon nanotubes have good mechanical performance and relatively light mass, cables containing carbon nanotubes have higher mechanical strength, lighter mass, and aerospace and space facilities than cables made of pure metal cores. This also applies to special areas such as

Third, the cable core formed by the conductive material and the carbon nanotubes is more conductive than the cable core formed by the pure carbon nanotubes.

Hereinafter, a cable and a method of manufacturing the same according to the present invention will be described in detail with reference to the exemplary drawings.

The cable according to the present embodiment includes at least one cable core, at least one insulating layer, at least one shield layer, and one protective layer.

1 is a cross-sectional view of a cable 10 according to a first embodiment of the present invention. The cable 10 is a coaxial cable. The coaxial cable 10 may include a cable core 110, an insulating layer 120 covering an outer surface of the cable core 110, a shield layer 130 covering an outer surface of the insulating layer 120, and And a protective layer 140 covering the outer surface of the shield layer 130. Here, the cable core 110, the insulating layer 120, the shield layer 130, and the protective layer 140 are coaxially provided.

The cable core 110 includes at least one composite carbon nanotube wire. Specifically, the cable core 110 may be configured by one composite carbon nanotube wire, or may be configured by a plurality of composite carbon nanotube wires installed to be wound or parallel to each other. In this embodiment, the cable core 110 is one composite carbon nanotube wire. The diameter of the cable core 110 is 4.5 nm to 1 mm. It is preferable that the said diameter is 10 micrometers-30 micrometers. The axial direction of the composite carbon nanotube wire and the axial direction of the cable core 110 are the same. The axial direction of the cable core 110 refers to the longitudinal direction of the cable core 110.

The composite carbon nanotube wire is composed of carbon nanotubes and a conductive material. Specifically, the composite carbon nanotube wire includes a plurality of carbon nanotubes, and at least one conductive material layer is coated on the outer surface of each carbon nanotube. Here, the length of each carbon nanotube is almost the same. The plurality of carbon nanotubes are connected to each other by the force of Van der Waals to form a composite carbon nanotube wire. In the composite carbon nanotube line, the plurality of carbon nanotubes are arranged in Preferred Orientation along the axial direction of the cable core. In addition, the twisted composite carbon nanotube wire may be further formed to form a twisted composite carbon nanotube wire. In the twisted composite carbon nanotube wire, the plurality of carbon nanotubes are arranged in a spiral along the axial direction of the composite carbon nanotube wire. That is, the plurality of carbon nanotubes are arranged so as to wind around the axis of the composite carbon nanotube line. The diameter of the composite carbon nanotube wire is 4.5 nm to 100 µm. It is preferable that the diameter is 10 micrometers-30 micrometers.

FIG. 2 is a cross-sectional view of the structure of the single stranded carbon nanotubes 111 of the composite carbon nanotube wire of FIG. 1. At least one conductive material layer is coated on the outer surface of each carbon nanotube 111 in the composite carbon nanotube wire. The conductive material layer includes a wetting layer 112, a transition layer 113, a conductive layer 114, and an anti-oxidation layer 115. The wetting layer 112 is coated on the outer surface of the carbon nanotubes 111, the transition layer 113 is coated on the outer surface of the wetting layer 112, and the conductive layer 114 is the transition layer. The outer surface of 113 is coated, and the antioxidant layer 115 is coated on the outer surface of the conductive layer 114.

Since the wettability of the carbon nanotubes 111 and most of the metals are different, in order to better bond the carbon nanotubes 111 and the conductive layer 114, a wetting layer 112 is provided therebetween. The material of the wet layer 112 may be a metal or an alloy thereof having excellent wettability with the carbon nanotubes 111 such as nickel (Ni), palladium (Pd), or titanium (Ti). The wet layer 112 has a thickness of 1 nm to 10 nm. In this embodiment, the material of the wet layer 112 is nickel (Ni), the thickness is 2nm. In addition, the wet layer 112 may not be provided.

The transition layer 113 is installed to better bond the wet layer 112 and the conductive layer 114. The material of the transition layer 113 is a material having excellent bonding property with the material of the wet layer 114 and the material of the conductive layer 114. The transition layer 113 has a thickness of 1 nm to 10 nm. In this embodiment, the material of the transition layer 113 is copper (Cu), the thickness is 2nm. In addition, the transition layer 113 may not be provided.

The conductive layer 114 is provided to have excellent conductivity in the composite carbon nanotube wire. The material of the conductive layer 114 is a metal having excellent conductivity such as copper (Cu), silver (Ag), gold (Au), nickel (Ni), palladium (Pd), titanium (Ti), or platinum (Pt). Or their alloys. The conductive layer 114 has a thickness of 1 nm to 20 nm. In this embodiment, the material of the conductive layer 114 is silver (Ag) and the thickness is 5nm.

The anti-oxidation layer 115 is installed to prevent the conductive layer 114 from being oxidized in air and deteriorating the conductivity of the cable core 110 in the manufacturing process of the cable 10. The material of the anti-oxidation layer 115 may be a metal or an alloy thereof having a relatively stable property that is not easily oxidized in air such as gold (Au) or platinum (Pt). The thickness of the antioxidant layer 115 is 1 nm to 10 nm. In this embodiment, the material of the antioxidant layer 115 is platinum (Pt), the thickness is 2nm. In addition, the antioxidant layer 115 may not be provided.

In order to improve the strength of the cable 10, a reinforcing layer 116 may be further provided on the outer surface of the antioxidant layer 115. The material of the reinforcement layer 116 may be a high strength polymer such as polyvinyl alcohol (PVA), polyparaphenylene benzobisoxazole (PBO), polyethylene (PE), or polyvinyl chloride (PVC). . The reinforcement layer 116 has a thickness of 0.1 μm to 1 μm. In this embodiment, the material of the reinforcement layer 116 is polyvinyl alcohol (PVA), and the thickness is 0.5 탆. In addition, the reinforcement layer 116 may not be provided.

The insulating layer 120 is used for electrical insulation. The material of the insulating layer 120 is selected from polytetrafluoroethylene (PTFE), polyethylene (PE), polypropylene (PP), polyethylene foam, or nano clay / polymer composite material. Can be. Nanoclays in nanoclay / polymer composites are nano-grade layered silicate minerals. The silicate mineral is composed of a plurality of silicate hydrates and a predetermined amount of aluminum oxide, alkali metal oxide and alkaline earth metal oxide. The nanoclay is excellent in flame retardancy. The nanoclay is nano kaolin or montmorillonite, and the polymer material is silicone resin, polyamide, and polyolefin such as polyethylene (PE) and polypropylene (PP). do. However, the material of the insulating layer 120 is not limited to the above materials. In this embodiment, the polymeric material uses polyethylene foam.

The shield layer 130 is formed of a conductive material, and serves to shield electromagnetic interference or interference of external signals. The shield layer 130 may be formed by coating a knitted fabric or a metal thin film by a plurality of metal wires on the outer surface of the insulating layer 120, and the plurality of carbon nanotubes. Line, single layer carbon nanotube film in which carbon nanotubes are arranged in order, multi-layer carbon nanotube film in which carbon nanotubes are arranged in order, or carbon in which carbon nanotubes are arranged in disorder It may be formed by coating a nanotube film on the outer surface of the insulating layer 120, or may be formed by directly coating a composite material including carbon nanotubes on the outer surface of the insulating layer 120. .

Here, as the material of the metal wire or the metal thin film, a metal having excellent conductivity such as copper (Cu), gold (Au), or silver (Ag) or an alloy thereof is used. The carbon nanotube wire, a single layer or a multilayer carbon nanotube film in which carbon nanotubes are arranged in an orderly manner, includes a plurality of carbon nanotube segments. Each carbon nanotube fragment comprises a plurality of carbon nanotubes of similar length and arranged parallel to each other. Ends and ends of the plurality of carbon nanotube fragments are connected to each other by van der Waals forces to form a continuous carbon nanotube film or carbon nanotube wire. The composite material may be a composite of metal and carbon nanotubes or a composite of polymer and carbon nanotubes. The polymer material is a polymer material such as polyethylene terephthalate (PET), polycarbonate (PC), acrylonitrile butadiene styrene (ABS) and polycarbonate / acrylonitrile butadiene styrene (PC / ABS). After the carbon nanotubes are uniformly dispersed in the polymer solution, the mixed solution is uniformly applied to the outer surface of the insulating layer 120 and cooled to form a polymer layer including carbon nanotubes. In addition, the shield layer 130 may be formed by coating the insulating layer 120 in a carbon nanotube composite thin film or a carbon nanotube composite linear structure. In the carbon nanotube metal composite thin film or carbon nanotube metal composite linear structure, carbon nanotubes are arranged in an orderly manner, and at least one conductive material layer is coated on an outer surface of the carbon nanotubes. In addition, the shield layer 130 may be configured by combining the plurality of materials described above with the outer surface of the insulating layer 120.

The protective layer 140 is formed of an insulating material such as nanoclay / polymer material. Here, the nanoclay uses nano kaolin or montmorillonite, and the polymer material uses silicone resin, polyamide, and polyolefin such as polyethylene and polypropylene. However, the material of the protective layer 140 is not limited to the above materials. In this embodiment, the material of the protective layer 140 uses a nano-kaolin / polyethylene composite material. The kaolin / polyethylene composite is a low smoke halogen-free material having excellent mechanical performance and flame retardancy. Thus, the kaolin / polyethylene composite material not only provides protection to the cable 10, but also prevents mechanical, physical and chemical damage and at the same time meets the needs of environmental protection.

Hereinafter, a method of manufacturing the cable 10 according to the present embodiment will be described in detail with reference to FIGS. 3 and 4. The manufacturing method of the cable 10 is as follows.

Process 1: A carbon nanotube array 216 is provided. It is preferred that the array is a superaligned array carbon nanotube array.

The carbon nanotube array according to the present invention is one or several of single wall carbon nanotube arrays, double wall carbon nanotube arrays or multiwall carbon nanotube arrays.

In this embodiment, the superaligned array carbon nanotube array is formed by Chemical Vapor Deposition (CVD). The process is as follows.

(a) Provide a flat growth substrate. As the substrate, a P-type or N-type silicon wafer may be used, or a silicon wafer having an oxide layer formed on the surface thereof. In this embodiment, the growth substrate uses a 4 inch silicon wafer.

(b) forming a uniform catalyst layer on the surface of the growth substrate. As the material of the catalyst layer, any one of alloys of iron (Fe), cobalt (Co), nickel (Ni) or any combination of the above metals can be used.

(c) The growth substrate on which the catalyst layer is formed is subjected to an annealing treatment for about 30 to 90 minutes in air at 700 to 900 ° C.

(d) The annealed growth substrate is placed in a reactor with a protective gas and heated to 500 to 740 ° C. Thereafter, a carbon source gas is injected into the reactor and reacted for about 5 to 30 minutes to grow carbon nanotubes on the growth substrate to obtain a carbon nanotube array. The carbon nanotube array has a height of 200 μm to 400 μm. The carbon nanotube array is a pure carbon nanotube array formed of a plurality of carbon nanotubes grown in parallel with each other and perpendicular to the growth substrate. That is, by controlling the above growth conditions, almost no other substance (amorphous carbon or metal granules of the catalyst) is present in the grown carbon nanotube array. In the carbon nanotube array, the carbon nanotubes are closely connected to each other by the force of van der Waals to form an array. The area of the carbon nanotube array and the growth substrate is almost equal.

As the carbon source gas, ethylene (C ₂ H ₄ ), methane (CH ₄ ), acetylene (C ₂ H ₂ ), and the like, which are relatively active in chemical properties, may be used. As the protective gas, nitrogen (N) or an inert gas may be used. Can be used. In this embodiment, acetylene is used as the carbon source gas, and argon (Ar) gas is used as the protective gas.

Process 2: The carbon nanotube structure 214 is pulled out of the carbon nanotube array 216 described above with a drawing tool.

Specific manufacturing method of the carbon nanotube structure 214 is as follows.

(a) In the carbon nanotube array 216, a plurality of carbon nanotube fragments having a constant width are selected. In this embodiment, the adhesive tape or pin having a constant width is contacted with the carbon nanotube array 216 to select a plurality of pieces of carbon nanotubes having a constant width.

(b) The selected plurality of carbon nanotube fragments are drawn at a constant speed along a direction substantially perpendicular to the growth direction of the carbon nanotube array 216 to obtain a continuous carbon nanotube structure 214.

In the drawing process, under the action of the pulling force, the plurality of carbon nanotube fragments are gradually detached from the growth substrate along the direction of the pulling force. At this time, the ends of the detached carbon nanotube fragments are connected to the ends of the other carbon nanotube fragments by van der Waals' forces, respectively, to form a continuous carbon nanotube structure 214 having a uniform and constant width. The carbon nanotube structure 214 includes a plurality of carbon nanotube fragments whose ends and ends are interconnected and aligned. The arrangement direction of the carbon nanotubes in the carbon nanotube structure 214 is substantially parallel to the pulling direction of the carbon nanotube structure 214.

The carbon nanotube structure 214 is a carbon nanotube film or carbon nanotube wire. In other words, when the width of the plurality of selected carbon nanotube fragments is relatively wide, the carbon nanotube structure 214 obtained by drawing is a carbon nanotube film (see FIG. 5 for the microcosmic structure), and the selected plurality When the width of the carbon nanotube fragment is relatively narrow, the carbon nanotube structure 214 obtained by drawing is close to the carbon nanotube line.

The carbon nanotube structure 214 in which the direct pull is obtained and the carbon nanotubes are arranged in a preferential direction has better uniformity than the carbon nanotube structure in which the carbon nanotubes are arranged randomly. In addition, the manufacturing method of the carbon nanotube structure 214 obtained directly by pulling is applied to realize the industrialization simply and quickly.

Step 3: A cable core is obtained by forming at least one conductive material layer on the outer surface of the carbon nanotube structure 214 to form a composite carbon nanotube wire 222.

In this embodiment, the conductive material layer is deposited by physical vapor deposition (PVD), such as vacuum deposition or ion sputtering. It is preferable to deposit a conductive material layer by a vacuum deposition method.

The procedure for forming the conductive material layer by vacuum deposition is as follows.

(a) For the first time, a vacuum vessel 210 is provided.

The vacuum vessel 210 has a deposition section. At least one vaporizing sources 212 are provided above and below the deposition section. The at least one evaporation source 212 is provided in the stretching direction of the carbon nanotube structure 214 in the order in which at least one conductive material layer is formed. Each of the evaporation sources 212 is all heated by one heater (not shown). The carbon nanotube structure 214 is installed to be spaced apart from the evaporation sources 212 between the upper and lower evaporation sources 212. Upper and lower surfaces of the carbon nanotube structure 214 respectively face the upper and lower evaporation sources 212. The vacuum vessel 210 may reach a predetermined degree of vacuum by an external vacuum pump (not shown). The material of the evaporation source 212 is a conductive material to be deposited on the carbon nanotube structure 214.

(b) Next, the material of the evaporation source 212 is evaporated or sublimed by heating the evaporation source 212 to obtain a conductive material vapor. The conductive material vapor meets the cold carbon nanotube structure 214 and aggregates on the upper and lower surfaces of the carbon nanotube structure 214 to form a conductive material layer. Since there is a gap between the carbon nanotubes in the carbon nanotube structure 214 and the thickness of the carbon nanotube structure 214 is relatively thin, the conductive material is infiltrated into the carbon nanotube structure 214. As a result, the conductive material is deposited on the outer surface of each carbon nanotube. For microscopic structures of the carbon nanotube structure 214 on which the conductive material layer is deposited, see the photographs of FIGS. 6 and 7.

In addition, by adjusting the distance between the carbon nanotube structure 214 and each evaporation source 212 and the distance between the evaporation sources 212, each evaporation source 212 has a corresponding deposition zone. When deposition of a plurality of conductive material layers is required, the plurality of evaporation sources 212 are simultaneously heated to pass the carbon nanotube structures 214 through the corresponding deposition zones of the respective evaporation sources 212 to the carbon nanotube structures 214. ), A plurality of conductive material layers are formed. In order to improve the density of the conductive material vapor and prevent the conductive material from being oxidized, the degree of vacuum in the vacuum vessel 210 is made larger than 1 Pa (Pascal). In this embodiment, the degree of vacuum in the vacuum vessel 210 is 4 × 10 ⁻⁴ Pa.

In addition, the carbon nanotube array 216 of step 1 may be directly installed in the vacuum vessel 210 to form a composite carbon nanotube wire 222. The procedure is as follows. (a) First, the carbon nanotube array 216 is drawn in the vacuum vessel 210 with a drawing tool to obtain a carbon nanotube structure 214. (b) Next, the at least one evaporation source 212 is heated to deposit at least one conductive material layer on the outer surface of the carbon nanotube structure 214. The carbon nanotube structure 214 can be continuously drawn at a predetermined speed, and the carbon nanotube structure 214 can be continuously passed through the deposition zone of the evaporation source to produce the composite carbon nanotube wire 222 continuously. .

In this embodiment, the procedure of forming at least one conductive material layer by vacuum deposition is as follows. (a) A single wet layer is formed on the outer surface of the carbon nanotube structure 214. (b) A single transition layer is formed on the outer surface of the wet layer. (c) One conductive layer is formed on the outer surface of the transition layer. (d) One layer of antioxidant layer is formed on the outer surface of the conductive layer. That is, the carbon nanotube structure 214 is continuously passed through the deposition zone of the evaporation source 212 corresponding to each material layer. Among them, the manufacturing procedures of the wet layer, the transition layer and the antioxidant layer may be omitted.

In addition, after forming at least one conductive material layer on the outer surface of the carbon nanotube structure 214, a reinforcing layer may be further formed on the outer surface of the conductive material layer. Specifically, the carbon nanotube structure 214 in which the at least one conductive material layer is formed is passed through the container 220 containing the polymer solution. In the passage, the entire carbon nanotube structure 214 is penetrated by the polymer solution contained in the vessel 220. The polymer solution is attached to the outer surface of the conductive material layer by intermolecular action. The attached polymer solution solidifies to form a reinforcement layer.

When the carbon nanotube structure 214 is a carbon nanotube wire, the carbon nanotube wire in which at least one conductive material layer is formed, that is, the composite carbon nanotube wire 222, does not need any subsequent processing.

When the carbon nanotube structure 214 is a carbon nanotube film, the method of forming the composite carbon nanotube wire 222 further includes mechanical treatment of the carbon nanotube film having at least one conductive material layer formed thereon. do. The mechanical treatment is of two ways as follows.

First method: The composite carbon nanotube wire 222 is formed by twisting the carbon nanotube structure 214 on which at least one conductive material layer is formed with a mechanical external force.

Second method: The composite carbon nanotube wire 222 is formed by cutting the carbon nanotube structure 214 in which at least one conductive material layer is formed.

The twisting process of forming the composite carbon nanotube wire 222 has two methods as follows.

(a) A drawing tool attached to one end of the carbon nanotube structure 214 is fixed to a rotary mover to twist the carbon nanotube film. As a result, the composite carbon nanotube wire 222 is formed.

(b) Provide a spinneret capable of adhering the carbon nanotube structure 214 to the tail. After combining the carbon nanotube structure 214 and the tail of the spinneret, the spinneret is rotated to twist the carbon nanotube structure 214 to form a composite carbon nanotube wire 222. The spinning method of the spinneret is not limited. That is, the spinneret can be rotated in a clockwise direction, can be rotated in a counterclockwise direction, or can be rotated by combining a clockwise direction and a counterclockwise direction.

There are two ways to twist the carbon nanotube structure as follows.

Method 1: A composite carbon nanotube line 222 may be formed by twisting both ends of the carbon nanotube structure 214 along the direction in which the carbon nanotubes are arranged.

Method 2: A composite carbon nanotube line 222 can be formed by twisting both ends of the carbon nanotube structure 214 perpendicular to the direction in which the carbon nanotubes are arranged.

Among them, the method 1 is preferable. The composite carbon nanotube wire 222 formed by the above method has a torsional structure (see scanning electron micrograph of FIG. 8).

The process of forming the composite carbon nanotube wire 222 by cutting is as follows.

The carbon nanotube structure 214 is cut along the pulling direction to form a plurality of composite carbon nanotube wires 222. The plurality of carbon nanotube wires 222 may be further overlapped and twisted to form a composite carbon nanotube wire 222 having a relatively large diameter. As a result, a cable core having a relatively large diameter can be obtained.

In addition, the manufacturing method of the composite carbon nanotube wire 222 of the present invention is not limited to the above method. As long as it is possible to form the composite carbon nanotube wire 222 with the carbon nanotube film, the present invention belongs to the category to be protected.

The composite carbon nanotube wire 222 may be collected in the first roller 224. The collection method is to wind the composite carbon nanotube wire 222 on the first roller 224. The composite carbon nanotube wire 222 is used as a cable core.

In addition, the formation of the carbon nanotube structure 214, the formation of at least one conductive material layer, the formation of the reinforcing layer, the bits for the carbon nanotube structure 214, and the process of the composite carbon nanotube wire 222 By performing all the collection procedures and the like in the vacuum vessel 210, the composite carbon nanotube wire 222 can be continuously produced.

Step 4: At least one insulating layer is formed on the outer surface of the cable core.

When the cable core includes only one composite carbon nanotube wire 222, the molten polymer is pressed onto the outer surface of the composite carbon nanotube wire 222 by a first squeezing device 230. To form the insulating layer. In this embodiment, the molten polymer is polyethylene foam. As soon as the composite carbon nanotube wire 222 emerges from the first compression device, the molten polymer compressed on the outer surface of the carbon nanotube wire 222 is expanded to form an insulating layer.

When the insulating layer is a plurality of layers, the above procedure may be repeatedly performed.

Step 5: At least one shield layer is formed on the outer surface of the insulating layer.

The shielding band 232 provided by the second roller 234 is wrapped around the insulating layer to form a shielding layer. The shield band 232 has a band-like film structure or a linear structure. The band-like film structure includes a metal thin film, a carbon nanotube film, a composite carbon nanotube film, and the like, and the linear structure includes a carbon nanotube wire, a composite carbon nanotube linear structure, or a metal wire. In addition, the shield band 232 may be formed by knitting the plurality of materials. The shield band 232 may be attached to an outer surface of the insulating layer through an adhesive to form a shield layer, or may be directly wrapped on an outer surface of the insulating layer to form a shield layer.

In the present embodiment, the shield layer is formed by a plurality of carbon nanotube wires. The shield layer is formed by directly wrapping the carbon nanotube wire directly on the outer surface of the insulating layer, or by knitting the plurality of carbon nanotube wires and wrapping the carbon nanotube wire on the outer surface of the insulating layer in a net-like structure. Each carbon nanotube line comprises a plurality of carbon nanotube fragments obtained from a carbon nanotube array. Each carbon nanotube fragment is formed by a plurality of carbon nanotubes of similar length and parallel to each other. The ends and ends of the carbon nanotube fragments are connected to each other by the force of Van der Waals.

In order to completely shield the cable core, it is preferable to wrap the shield band 232 on the outer surface of the insulating layer so that there is no gap. That is, the sides of the shield band 232 adjacent to each other are wrapped to overlap. The shield band 232 having a linear structure such as the carbon nanotube wire, the composite carbon nanotube wire structure, or the metal wire is directly wrapped on the outer surface of the insulating layer, or the plurality of carbon nanotube wires are knitted to form a net structure. To the outer surface of the insulating layer. In other words, a plurality of carbon nanotube wires or metal wires are wrapped in a different spiral direction on the outer surface of the insulating layer through a plurality of bobbins 236 to form a shield layer.

In addition, when the shield layer is a plurality of layers, it is possible to obtain a plurality of shield layers by repeating the above procedure.

Step 6: A protective layer is formed on the outer surface of the shield layer.

The protective layer is formed on an outer surface of the shield layer through a second pressing device. That is, the protective layer is formed on the outer surface of the shield layer by pressing the polymer in the molten state to the outer surface of the shield layer and then cooling the polymer.

The cable formed by the above method can be collected in the third roller 260. Collecting the cable on a roller is for convenience of storage or transportation.

9 is a cross-sectional view of the cable 30 according to the second embodiment of the present invention. The cable 30 includes a plurality of cable cores 310 (seven are shown in FIG. 9), a plurality of insulating layers 320, a shield layer 330, and a protective layer 340. Each of the plurality of insulating layers 320 covers an outer surface of each cable core 310, the shield layer 330 covers the outside of the plurality of insulating layers 320, and the protective layer 340 is The outer surface of the shield layer 330 is covered. An insulating material may be filled in the gap between the shield layer 330 and the insulating layer 320. Among them, the structure, material, and manufacturing method of each cable core 310, each insulating layer 320, shield layer 330, and protective layer 340 include the cable core 110 and insulating layer of the first embodiment. The structure, material, and manufacturing method of the 120, the shield layer 130, and the protective layer 140 are basically the same.

10 is a cross-sectional view of the cable 40 according to the third embodiment of the present invention. The cable 40 includes a plurality of cable cores 410 (five are shown in FIG. 10), a plurality of insulating layers 420, a plurality of shield layers 430, and a protective layer 440. Each of the plurality of insulating layers 420 covers an outer surface of each cable core 410, and each of the plurality of shield layers 430 covers an outer surface of each insulating layer 420, and the protective layer ( 440 covers the outside of the plurality of shield layers 430. The action of the shield layer 430 shields each cable core 410 alone. In this case, an external element may not only prevent interference with an electrical signal transmitted inside the cable core 410, but also prevent interference between other electrical signals transmitted inside each cable core 410. Here, the structure, material and manufacturing method of each of the cable core 410, the insulating layer 420, the shield layer 430, and the protective layer 440 are the cable core 110 and the insulating layer 120 of the first embodiment. The structure, material, and manufacturing method of the shield layer 130 and the protective layer 140 are basically the same.

FIG. 11 is a cross-sectional view of the cable 50 according to the fourth embodiment of the present invention, and FIG. 12 is a perspective view of the cable core 520 in the cable 50 of FIG.

Referring to FIG. 11, the cable 50 is a coaxial cable. The coaxial cable 50 may include a cable core 520, an insulating layer 530 covering an outer surface of the cable core 520, a shield layer 540 covering an outer surface of the insulating layer 530, and And a protective layer 550 covering the outer surface of the shield layer 540. Among them, the cable core 520, the insulating layer 530, the shield layer 540, and the protective layer 550 are provided coaxially.

Referring to FIG. 12, the cable core 520 includes a carbon nanotube linear structure 500 and a conductive material layer 510 covering an outer surface of the carbon nanotube linear structure 500. Specifically, the conductive material layer 510 includes a wetting layer 512 directly bonded to the outer surface of the carbon nanotube linear structure, and a transition layer 513 coated on the outer surface of the wetting layer 512. And a conductive layer 514 coated on the outer surface of the transition layer 513 and an antioxidant layer 515 coated on the outer surface of the conductive layer. The conductive material layer 510 includes the conductive layer 514 as a minimum. The wet layer 512, the transition layer 513, and the antioxidant layer 515 may not be provided. The diameter of the cable core 520 is greater than 1 μm. Preferably, the diameter of the cable core 520 is 10 µm to 30 µm or 1 cm. In order to improve the strength of the cable 50, a reinforcing layer 516 may be further provided outside the conductive material layer 510.

The structures and materials of the wetting layer 512, the transition layer 513, the conductive layer 514, the antioxidant layer 515, and the reinforcing layer 516 of this embodiment are the same as that of the wetting layer 112 of the first embodiment. And the structure and material of the transition layer 113, the conductive layer 114, the antioxidant layer 115, and the reinforcement layer 116.

The carbon nanotube linear structure 500 includes at least one carbon nanotube wire 502. The carbon nanotube wire 502 has a diameter of 4.5 nm to 100 μm.

Referring to FIG. 13, the carbon nanotube linear structure 500 may be a bundle or torsional structure formed by a plurality of carbon nanotube lines 502. When the diameter of the carbon nanotube linear structure 500 is smaller than 100 μm, the cable 50 formed by the carbon nanotube linear structure 500 may be applied to a signal transmission region, and the carbon nanotube linear structure 500 ) Is larger than 100 μm, the cable 50 formed by the carbon nanotube linear structure 500 may be applied to the power transmission region.

The carbon nanotube wire 502 may be a bundle or twisted carbon nanotube wire by a plurality of carbon nanotubes.

Referring to FIG. 14, the bundled carbon nanotube lines 502 include a plurality of carbon nanotube fragments arranged in a preferred direction along the axial direction of the cable core. Each carbon nanotube fragment comprises a plurality of bundles of carbon nanotubes of similar length and arranged parallel to each other. Ends and ends of the plurality of carbon nanotube fragments are connected to each other by van der Waals forces, and the bundle of carbon nanotubes includes a plurality of carbon nanotubes arranged in the same direction. In the bundled carbon nanotube wire 502, a plurality of carbon nanotubes are arranged in a preferential direction along the axial direction of the line, and the ends and ends of the plurality of carbon nanotubes are connected to each other by van der Waals forces. do. The bundle carbon nanotube wire 502 preferably has a diameter of 10 μm to 30 μm.

The torsional carbon nanotube wire 502 includes a plurality of carbon nanotubes arranged in a spiral shape along the axial direction of the line. That is, the carbon nanotubes 502 include a plurality of carbon nanotubes arranged in a shape wound around the axis. Ends and ends of the plurality of carbon nanotubes are connected to each other by van der Waals forces. It is preferable that the diameter of the twisted carbon nanotube wire 502 is 10 μm to 30 μm.

The carbon nanotubes in the carbon nanotube linear structure 500 include single-walled carbon nanobubbles, double-walled carbon nanobubbles, or multi-walled carbon nanobubbles. The diameter of the single-wall carbon nanobube is 0.5 nm to 50 nm, the diameter of the double-wall carbon nanobube is 1 nm to 50 nm, and the diameter of the multi-walled carbon nanobube is 1.5 nm to 50 nm.

Compared with the prior art, the cable and the method of manufacturing the composite carbon nanotube wire as a core according to the present invention has the following advantages.

First, a composite carbon nanotube line includes a plurality of carbon nanotube fragments connected to each other by van der Waals' forces and arranged in a direction, and a conductive layer is formed on the outer surface of each carbon nanotube. Among them, carbon nanotube fragments serve as a challenge and support. The composite carbon nanotube wire formed after the carbon nanotube layer is formed is thinner than the conventional metal conductor wire and is suitable for the production of ultra-fine cables.

Second, since the carbon nanotubes have a hollow tube structure, and the conductive material layer formed on the outer surface of the carbon nanotubes is several nanometers thick, the skin phenomenon does not basically occur when current flows through the conductive material layer. In this case, the signal loss of the cable in the signal transmission process can be avoided.

Third, because carbon nanotubes have excellent mechanical performance and hollow tube structure, carbon nanotube cables have higher mechanical strength, lighter mass, and aerospace and space facilities than conventional metal conductor cables. This also applies to special areas such as

Fourth, the cable core made of a composite carbon nanotube wire including carbon nanotubes provided with a conductive material layer on the outer surface is more conductive than the cable core made of pure carbon nanotube wire.

Fifth, since the composite carbon nanotube wire is formed by twisting the carbon nanotube film directly or obtained directly from the carbon nanotube array, the manufacturing method is simple and manufacturing cost is low.

Sixth, the procedure for obtaining the carbon nanotube structure in the carbon nanotube array and the procedure for forming at least one layer of the conductive material layer are all performed in a vacuum container, which is advantageous for scaled-up production of cable cores. Therefore, it is also advantageous to scale production of cables.

As mentioned above, although this invention was demonstrated using the preferable Example, the scope of the present invention is not limited to a specific Example and should be interpreted by the attached Claim. In addition, those skilled in the art should understand that many modifications and variations are possible without departing from the scope of the present invention.

1 is a cross-sectional view of a cable according to a first embodiment of the present invention.

FIG. 2 is a structural cross-sectional view of a single strand of carbon nanotubes in the cable of FIG. 1. FIG.

3 is a flowchart of a cable manufacturing method according to the first embodiment of the present invention.

4 is a structural diagram of a cable manufacturing apparatus according to a first embodiment of the present invention.

5 is a scanning electron micrograph of a carbon nanotube film according to a first embodiment of the present invention.

6 is a scanning electron micrograph of a carbon nanotube film having a conductive material layer formed thereon according to a first embodiment of the present invention.

7 is a transmission electron microscope photograph of carbon nanotubes in a carbon nanotube film on which a conductive material layer according to a first embodiment of the present invention is formed.

FIG. 8 is a scanning electron micrograph of a linear structure of a torsional carbon nanotube formed by twisting a carbon nanotube structure according to a first embodiment of the present invention.

9 is a cross-sectional view of a cable according to a second embodiment of the present invention.

10 is a cross-sectional view of a cable according to a third embodiment of the present invention.

11 is a cross-sectional view of a cable according to a fourth embodiment of the present invention.

12 is a perspective view of the cable core in the cable of FIG.

FIG. 13 is a cross-sectional view of the carbon nanotube linear structure in the cable core of FIG. 12. FIG.

14 is a scanning electron micrograph of a bundled carbon nanotube wire according to a fourth embodiment of the present invention.

<Description of Drawing Symbols>

10 --- cable 110 --- cable core

111 --- Carbon Nanotubes 112 --- Wet Layer

113 --- Transition Layer 114 --- Conductive Layer

115 --- Antioxidant Layer 116 --- Reinforcement Layer

120 --- insulation layer 130 --- shield layer

140 --- Protective layer 210 --- Vacuum vessel

212 --- Evaporation Sources 214 --- Carbon Nanotube Structure

216 --- carbon nanotube array 220 --- container

222 --- Composite Carbon Nanotube Wire 224 --- First Roller

230 --- First Crimping Device 232 --- Shield Band

234 --- 2nd roller 236 --- bobbin

240 --- First Crimping Device 260 --- First Roller

Claims (15)

At least one cable core, at least one insulating layer covering the cable core, at least one shield layer covering the insulating layer, and a protective layer covering the shield layer, wherein the cable core is In a cable comprising a plurality of carbon nanotubes and a conductive material, The plurality of carbon nanotubes and the conductive material constitutes at least one composite carbon nanotube wire, The plurality of carbon nanotubes are arranged in order along the axial direction of the cable core among the composite carbon nanotube wire, At least one conductive material layer is coated on the outer surface of each carbon nanotube. The method of claim 1, Among the composite carbon nanotube wires, carbon nanotubes are arranged in a preferred direction along the axial direction of the cable core. The method of claim 1, Among the composite carbon nanotube wires, carbon nanotubes are arranged in a spiral along the axial direction of the cable core. The method of claim 1, The composite carbon nanotube wire has a diameter of 4.5 nm to 100 µm. The method of claim 1, The cable core includes a plurality of composite carbon nanotube wires, The plurality of composite carbon nanotube wires are bundled in parallel to each other, or twisted with each other to form a twisted form. The method of claim 1, The material of the conductive material layer is copper, silver, gold, nickel, palladium, titanium, platinum or an alloy of any combination thereof, and the thickness of the conductive material layer is 1 nm to 20 nm. The method of claim 2, The cable core further includes a reinforcing layer installed on the outer surface of the conductive layer, The material of the reinforcing layer is polyvinyl alcohol, polyparaphenylene benzobisoxazole, polyethylene, or polyvinyl chloride. The method of claim 1, The cable core has a diameter greater than 4.5 nm. The method of claim 1, The cable includes a plurality of cable cores, a plurality of insulating layers each covering the outer surface of each cable core, a plurality of shield layers each covering the outer surface of each insulating layer, and one covering the plurality of shield layers. A cable comprising a protective layer. At least one cable core, at least one insulating layer covering the cable core, at least one shield layer covering the insulating layer, and one protective layer covering the shield layer, wherein the cable The core is a cable comprising a plurality of carbon nanotubes and a conductive material, The plurality of carbon nanotubes in the cable core form at least one carbon nanotube linear structure, The plurality of carbon nanotubes are arranged in order along the axial direction of the cable core among the carbon nanotube linear structure, And the conductive material covers the outer surface of the carbon nanotube linear structure to form at least one conductive material layer. In the cable manufacturing method, Providing at least one carbon nanotube structure; Obtaining a cable core by forming at least one conductive material layer on an outer surface of the at least one carbon nanotube structure; Forming at least one insulating layer on an outer surface of the cable core; Forming at least one shield layer on an outer surface of the insulating layer; And forming a protective layer on an outer surface of the shield layer. The method of claim 11, And the conductive material layer is formed by vacuum deposition or ion sputtering. The method of claim 11, The carbon nanotube structure is a method for producing a cable comprising a carbon nanotube film or carbon nanotube wire. The method of claim 13, If the carbon nanotube structure is a carbon nanotube film, the cable manufacturing method further comprises the step of performing a mechanical treatment for the carbon nanotube film on which the conductive material layer is formed. The method of claim 14, The mechanical treatment includes a procedure of twisting a carbon nanotube film on which a conductive material layer is formed or a procedure of cutting on a carbon nanotube film on which a conductive material layer is formed. .

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