WO2023120554A1 - Shielding material, and communication cable - Google Patents

Shielding material, and communication cable Download PDF

Info

Publication number
WO2023120554A1
WO2023120554A1 PCT/JP2022/047014 JP2022047014W WO2023120554A1 WO 2023120554 A1 WO2023120554 A1 WO 2023120554A1 JP 2022047014 W JP2022047014 W JP 2022047014W WO 2023120554 A1 WO2023120554 A1 WO 2023120554A1
Authority
WO
WIPO (PCT)
Prior art keywords
shielding
aid
braided body
metal
wire
Prior art date
Application number
PCT/JP2022/047014
Other languages
French (fr)
Japanese (ja)
Inventor
悠太 安好
達也 嶋田
文敏 今里
啓之 小林
博之 兒玉
修平 大図
Original Assignee
株式会社オートネットワーク技術研究所
住友電装株式会社
住友電気工業株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社オートネットワーク技術研究所, 住友電装株式会社, 住友電気工業株式会社 filed Critical 株式会社オートネットワーク技術研究所
Publication of WO2023120554A1 publication Critical patent/WO2023120554A1/en

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01BCABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B11/00Communication cables or conductors
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K9/00Screening of apparatus or components against electric or magnetic fields
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02ATECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A30/00Adapting or protecting infrastructure or their operation

Definitions

  • the present disclosure relates to shielding materials and communication wires.
  • the shield material shields electromagnetic waves entering the communication member from the outside and suppresses noise generation in the communication member.
  • the shield material shields electromagnetic waves emitted from the communication member to the outside, and also plays a role of suppressing the emitted electromagnetic waves from causing noise outside.
  • a braided body in which a plurality of metal wires are interwoven is often used as such a shield material. Since the braided body has high bending resistance, it is suitable as a shielding material provided for a communication member used in applications involving bending, such as a communication wire.
  • Patent Document 1 as a bending-resistant signal transmission cable, a quad coaxial structure line in which a plurality of coaxial signal lines are bundled so as to form a quad structure, an insulating tape covering the circumference of the quad coaxial structure line, and an insulating tape.
  • a structure is disclosed that includes a metal mesh (braid) arranged on the outer periphery and an insulating jacket that covers the metal mesh.
  • a braided body in which metal wires are woven can be suitably used as a shielding material for communication members such as communication wires.
  • the braided body has gaps between the metal wires due to its mesh structure, high-frequency (short wavelength) electromagnetic waves can pass through the gaps, and high-frequency electromagnetic waves can pass through the gaps. Adequate shielding can be difficult.
  • the speed of communication using communication wires is increasing, and it is required to effectively reduce the influence of noise even in a high frequency range using a shielding material.
  • metal foil may be placed around the core wire to improve the electromagnetic wave shielding effect.
  • the metal foil generally does not have as high bending resistance as the braided body, and the metal foil may break due to metal fatigue when, for example, the communication wire is repeatedly bent.
  • electromagnetic waves may pass through cracks in the metal foil caused by the breakage, resulting in an insufficient noise shielding effect.
  • metal foil it is conceivable to use a member other than the braided body that can reduce the transmission of electromagnetic waves in combination with the braided body to enhance the noise shielding effect in the high frequency range. If it does not have high bending resistance, it may not be possible to maintain a sufficient noise shielding effect when the communication wire is bent, as in the case of the metal foil.
  • the shield material according to the present disclosure includes a braided body in which a plurality of metal wires are woven, and a shielding aid that has fluidity and contains a conductive material and is arranged in contact with the braided body.
  • a communication wire according to the present disclosure includes a core wire having a conductor, an insulating layer covering the outer circumference of the conductor, and the shield material covering the outer circumference of the core wire.
  • the shielding material and the communication wire according to the present disclosure have high bending resistance and can maintain a high noise shielding effect even when subjected to repeated bending, and such a shielding material It becomes a communication wire.
  • FIG. 1A and 1B are diagrams showing a communication wire according to an embodiment of the present disclosure, which are a perspective view and a cross-sectional view taken perpendicularly to the axial direction, respectively.
  • FIG. 2A is a plan view showing a braid that constitutes a shield material according to an embodiment of the present disclosure
  • FIG. 2B is a cross-sectional view of the shielding material corresponding to cross-section AA of FIG. 2A, including the braid and the shielding aid.
  • the shield material according to the present disclosure includes a braided body in which a plurality of metal wires are woven, and a shielding aid that has fluidity and contains a conductive material and is arranged in contact with the braided body. .
  • the above shield material has a shielding aid containing a conductive material, so it has high noise shielding properties due to the contribution of the conductive material contained in the shielding aid. Since the shielding aid is composed of a fluid material, the shielding aid spreads over the inside and surface of the braided body, including the gaps between the metal wires of the braided body, and the area around the braided body. In addition, even when the shield material is bent, the spread and distributed state can be maintained. Therefore, the shield auxiliary agent can effectively assist the noise shielding property of the braided body, and the effect is maintained even after bending of the shield material.
  • the shielding aid can compensate for the deterioration of noise shielding properties caused by the damage. Furthermore, since the shielding aid is composed of a material having fluidity, unlike the case where the shielding aid is made of a solid material, it is less likely that the shielding performance will deteriorate due to accumulation of load or damage even when subjected to flexing. In this way, the shield material has high bending resistance, and can maintain a high noise shielding effect even after being repeatedly bent.
  • the shielding aid is in at least one of a state in which the voids between the plurality of metal wires constituting the braided body are filled, and a state in which the voids are covered. Then, in the braided body, the voids not occupied by the metal wires are blocked by the shielding aid containing the conductive material. As a result, it becomes difficult for electromagnetic waves to pass through the voids of the braided body, and the shielding material can efficiently suppress the transmission of electromagnetic waves even in a high frequency range, and high noise shielding properties can be obtained.
  • the shield adjuvant is preferably mucus-like. Then, in the shielding material, the shielding aid tends to stay in a state of being held by the braid, such as a state in which the gaps between the metal wires are filled or a state in which the gaps are covered. As a result, even if the shielding material is repeatedly bent, it becomes easier to maintain a state of exhibiting high noise shielding properties due to the effect of the shielding aid.
  • the shielding aid preferably contains metal powder as the conductive material and a non-conductive dispersion medium for dispersing the metal powder.
  • a fluid shielding aid containing a conductive material can be easily prepared and used.
  • the shield aid exhibits a high effect of improving noise shielding properties.
  • the content of the metal powder in the shielding aid is preferably 80% by mass or more and 98% by mass or less.
  • the shielding aid exhibits a high effect of improving noise shielding properties, and the effects of using a large amount of metal powder, such as a decrease in fluidity of the shielding aid, can be reduced.
  • the braid density of the braided body is preferably 50% or more and 95% or less. As a result, it is possible to obtain a high shielding performance in the shield material and reduce the amount of the metal wires forming the braided body.
  • the shielding aid is distributed over a wide area of the braided body, including the gaps between the metal wires, so the density of the metal wires is increased. Even if it is low to some extent, sufficient noise shielding properties can be exhibited.
  • the braid density is 80% or less.
  • a communication wire includes a core wire having a conductor and an insulating layer covering the outer circumference of the conductor, and the shield material covering the outer circumference of the core wire.
  • a shield material containing a braid and a shielding aid is arranged around the core wire, and the shield material reduces electromagnetic waves that enter the core wire and electromagnetic waves that are emitted from the core wire. and provide high noise shielding. Since the shielding aid constituting the shielding material has fluidity, the communication wire has high bending resistance, and the shielding material maintains high noise shielding properties even after repeated bending.
  • the communication wire further has a metal foil covering the outer periphery of the core wire, and the shield material covers the outer periphery of the metal foil.
  • the metal foil exhibits a noise shielding effect together with the shielding material in the communication wire.
  • the metal foil may be damaged due to metal fatigue and cracks may occur. Therefore, even if a crack occurs in the metal foil, the shielding material can suppress transmission of electromagnetic waves through the crack, and high noise shielding properties can be maintained. Therefore, even if the communication wire contains metal foil, which is a member that is relatively weak against bending, the communication wire as a whole has high bending resistance.
  • the thickness of the metal foil is preferably 15 ⁇ m or less. As a result, the flexibility of the metal foil increases, and the metal foil is less likely to be damaged even if it is repeatedly bent. As the metal foil becomes thinner, the noise shielding property of the metal foil becomes lower. Even if the foil is made thin, it is possible to secure sufficient noise shielding properties for the entire communication wire.
  • the communication wire may further have a sheath layer covering the outer circumference of the shield material.
  • the sheath layer serves to protect the shield material. In particular, it prevents the outflow and dissipation of the shielding aid made of fluid material.
  • a shielding material according to an embodiment of the present disclosure includes a braided body and a shielding aid, and functions as a shielding member that suppresses noise derived from electromagnetic waves by reducing transmission of electromagnetic waves. This shield material can be applied to various communication members, and is particularly suitable for communication wires.
  • a communication wire according to an embodiment of the present disclosure includes a shield material according to an embodiment of the present disclosure. In the following, the description will focus on the electric wire for communication.
  • FIG. 1A and 1B show the structure of a communication wire 1 according to an embodiment of the present disclosure.
  • 1A is a perspective view
  • FIG. 1B is a cross-sectional view of the communication wire 1 cut perpendicularly to the axial direction.
  • the communication wire 1 is configured as a coaxial wire.
  • the communication wire 1 includes a core wire 2 having a conductor 21 and an insulating layer 22 covering the outer circumference of the conductor 21 .
  • a metal foil 3 is provided around the core wire 2 .
  • a shield material (composite shield material) 4 according to an embodiment of the present disclosure is provided to cover the outer periphery of the metal foil 3 .
  • a sheath layer 5 is provided to cover the outer circumference of the composite shield material 4 .
  • the above-described communication wire 1 configured as a coaxial wire having a metal foil 3 and a composite shielding material 4 on the outer periphery of the core wire 2 is suitable for transmitting signals in a high frequency range of 1 GHz or higher. can be done.
  • the communication wire 1 according to the present disclosure is not limited to having the above structure as long as it surrounds the outer side of the core wire 2 and is provided with the composite shield material 4.
  • the core wire 2 can be configured such that a pair of insulated wires are twisted together or run in parallel to transmit a differential signal.
  • the core wire 2 may be configured as a quad structure including four insulated wires.
  • the metal foil 3 may be omitted when the influence of noise is not so great, or when the communication frequency is relatively low, for example, 1 MHz or less.
  • each of the layers described above is formed in direct contact with the outer periphery of the inner constituent layer, but the communication wire 1 may appropriately include constituent layers other than the layers described above. may be However, it is preferable that the metal foil 3 and the composite shielding material 4 are in direct contact with each other without intervening another constituent layer.
  • Each constituent member of the coaxial communication wire 1 exemplified above will be described below.
  • the core wire 2 is a signal wire responsible for transmission of electrical signals in the communication wire 1 and has a conductor 21 and an insulating layer 22 covering the outer circumference of the conductor 21 .
  • the material forming the conductor 21 and the insulating layer 22 is not particularly limited. Various metal materials can be used as a material for the conductor 21, but copper or a copper alloy is preferably used because of its high conductivity.
  • the conductor 21 may be configured as a single wire, but is preferably configured as a stranded wire in which a plurality of strands (for example, seven wires) are twisted together from the viewpoint of increasing flexibility when bending.
  • the insulating layer 22 insulates the conductor 21 in the core wire 2 and is made of a material containing an organic polymer.
  • the type of organic polymer is not particularly limited, and examples include olefin polymers such as polyolefins and olefin copolymers, halogen polymers such as polyvinyl chloride, various engineering plastics, elastomers, and rubbers.
  • the insulating layer 22 may contain additives as appropriate in addition to the organic polymer.
  • the metal foil 3 is configured as a thin film of a metal material.
  • the type of metal forming the metal foil 3 is not particularly limited, and examples thereof include copper, copper alloys, aluminum, aluminum alloys, and the like.
  • the metal foil 3 may be composed of a single kind of metal, or may be a laminate of layers of two or more kinds of metals.
  • the metal foil 3 may be formed of an independent metal thin film, or may be formed by bonding a metal layer to a base material such as a polymer film by vapor deposition, plating, adhesion, or the like.
  • the metal foil 3 functions as an outer conductor as a return path for electrical signals transmitted through the core wire 2, and together with the composite shield material 4, prevents electromagnetic waves entering the core wire 2 and the core wire 2.
  • the metal foil 3 is in direct contact with the outer composite shielding material 4, and the braided body 41 constituting the composite shielding material 4 is connected to the ground potential, so that the metal foil 3 is also grounded. is conducted to When the metal foil 3 has a base material, it is preferable that the side on which the metal thin film is provided faces outward from the viewpoint of ensuring conduction with the composite shield material 4 .
  • the metal foil 3 may be arranged vertically or horizontally around the outer periphery of the core wire 2, but arranging it vertically provides higher noise shielding performance.
  • the thickness of the metal foil 3 is not particularly limited, it is preferably 1 ⁇ m or more from the viewpoint of ensuring sufficient noise shielding properties.
  • the thickness of the metal foil 3 is preferably 15 ⁇ m or less, more preferably 10 ⁇ m or less, from the viewpoint of ensuring flexibility and enhancing the bending resistance of the communication wire 1 as a whole.
  • the composite shield material 4 provided outside the metal foil 3 has a high noise shielding effect. A sufficiently high noise shielding property can be obtained for the electric wire 1 as a whole.
  • the thickness shown here does not include the thickness of the base material, and refers to the thickness of the metal thin film only.
  • the thickness of the metal foil 3 including the substrate is preferably 30 ⁇ m or less.
  • the metal foil 3 is not necessarily provided, and may be omitted when the communication frequency is in a relatively low frequency range such as 1 MHz or less, or when the influence of noise is not serious. good. However, if the metal foil 3 is provided, it exhibits a high effect as a noise shielding member together with the composite shielding material 4 . In particular, in a high frequency range exceeding several hundred megahertz, the effect of noise shielding by the metal foil 3 increases.
  • the composite shield material 4 which will be described in detail later, is a composite of a braided body 41 made of a plurality of metal wires 41a and a shielding aid 42 containing a conductive substance and configured as a fluid material. It is.
  • the composite shielding material 4 functions as a noise shielding member that shields electromagnetic waves entering the core wire 2 and electromagnetic waves emitted from the core wire 2 in the communication wire 1 .
  • the braided body 41 forming the composite shield material 4 is connected to the ground potential.
  • the sheath layer 5 is not necessarily provided, but by being arranged as the outermost layer of the communication wire 1, the sheath layer 5 serves to protect the core wire 2, the metal foil 3, and the composite shield material 4 arranged inside. Fulfill.
  • the sheath layer 5 covers the outer periphery of the composite shield material 4, the fluid shielding aid 42 contained in the composite shield material 4 does not leak or dissipate to the outside of the communication wire 1.
  • the shielding aid 42 can be stably retained on the composite shielding material 4.
  • the communication wire 1 can be easily handled.
  • the sheath layer 5 is composed of a material containing an organic polymer.
  • the type of organic polymer is not particularly limited, and examples include olefin polymers such as polyolefins and olefin copolymers, halogen polymers such as polyvinyl chloride, various engineering plastics, elastomers, and rubbers.
  • the sheath layer 5 may contain additives as appropriate in addition to the organic polymer.
  • the sheath layer 5 may contain a powdered magnetic material, particularly a powdered soft magnetic material. Then, in the communication wire 1, the sheath layer 5, together with the metal foil 3 and the composite shield material 4, fulfills the noise shielding function.
  • soft magnetic materials include metal oxides such as ferrite, iron (pure iron or iron containing a small amount of carbon), various magnetic stainless steels, and alloys such as Fe—Ni alloys (permalloy).
  • the shield material (composite shield material) 4 is configured as a composite material including the braided body 41 and the shield aid 42 .
  • FIG. 2A shows an enlarged plan view of only the braided body 41 constituting the composite shield material 4.
  • FIG. 2B shows a cross-sectional view of the composite shield material 4 corresponding to the AA cross-sectional view of FIG. 2A.
  • a braided body 41 forming the composite shield material 4 has a structure in which a plurality of metal wires 41a are woven together. That is, a group of metal wires 41a arranged in a first direction and a group of metal wires 41a arranged in a second direction different from the first direction are intersected with each other and woven into a mesh.
  • the overall shape of the braided body 41 is not particularly limited, in the composite shield material 4 constituting the communication wire 1, the braided body 41 is braided into a hollow tubular shape.
  • the constituent material of the metal wire 41a constituting the braided body 41 is not particularly limited. can be exemplified.
  • the braid density of the braided body 41 that is, the ratio of the area occupied by the metal wires 41a on the surface of the braided body 41 is preferably 50% or more and 95% or less, as will be described later.
  • the shielding aid 42 that constitutes the composite shielding material 4 together with the braided body 41 is configured as a substance containing a conductive material.
  • the shield aid 42 has fluidity.
  • the shielding aid 42 is arranged in contact with the braided body 41 .
  • the fact that the shielding aid 42 has fluidity refers to a state in which it is not fixed in a fixed shape and position with respect to the braided body 41 at room temperature and can take an irregular shape and move.
  • the viscosity of the shielding aid 42 is 10000 mPa ⁇ s or less at 25°C.
  • the shielding aid 42 may be composed of any material as long as it contains a fluid and conductive material (including the case where the entire shielding aid 42 is composed of a fluid, electrically conductive material). However, as will be described in detail later, a preferred example is one in which metal powder is dispersed in a dispersion medium.
  • the shielding aid 42 may be placed in any arrangement as long as it is in contact with the braided body 41 , but is spread and distributed inside and/or on the surface of the braided body 41 . Further, the shielding aid 42 may be spread and distributed to the area around the braided body 41 (in the case of the communication wire 1, the area sandwiched between the metal foil 3 and the sheath layer 5). As shown in FIG. 2B, the shielding aid 42 preferably fills the gaps S between the plurality of metal wires 41a forming the braided body 41. As shown in FIG. Alternatively, the shielding aid 42 placed on the surface of the braided body 41 may cover the voids S.
  • the shielding aid 42 may have both a portion filled in the gap S and a portion covering the gap S. Further, as in the form shown in FIG. 2B , the shielding aid 42 may be continuous through the portion covering the surface of the braided body 41 between the portions that fill or cover the adjacent voids S. . The shielding aid 42 fills and/or covers the gaps S between the braids 41 so that the gaps S are blocked from the external space by the shielding aid 42 . In the initial state in which the composite shield material 4 is manufactured and arranged on the communication wire 1, even if the shielding aid 42 does not fill or cover the voids S of the braided body 41, the shielding aid 42 does not have fluidity. As a result, the shielding aid 42 gradually spreads over the interior and surface of the braided body 41, filling and/or covering the voids S. As shown in FIG.
  • the shielding aid 42 contains a conductive material, and the contribution of the conductive material can shield electromagnetic waves and reduce transmission of electromagnetic waves.
  • the shielding aid 42 since the shielding aid 42 is in contact with the braided body 41, conduction is formed between the conductive material in the shielding aid 42 and the braided body 41, and the current generated when shielding electromagnetic waves is It can escape to ground potential through braid 41 . Therefore, the shielding aid 42 functions as a noise shielding material that assists the noise shielding performance of the braided body 41 and the metal foil 3 .
  • the shielding aid 42 has fluidity and can spread inside and/or on the surface of the braided body 41 and further in the area around the braided body 41. It can contribute to the improvement of noise shielding properties.
  • the shielding aid 42 fills or covers the gaps S between the metal wires 41a of the braided body 41, and the shielding aid 42 contributes to the transmission of high-frequency electromagnetic waves through the gaps S. can be substantially reduced.
  • the shield aid 42 exhibits a high effect in improving noise shielding properties in the high frequency range.
  • the shielding aid 42 has fluidity and tends to form a liquid film in the region sandwiched or surrounded by the metal wires 41a. Due to the formation of the liquid film, the shielding aid 42 fills or covers the gaps S between the metal wires 41a without any gaps, and closes the gaps S, thereby particularly enhancing the noise shielding effect.
  • the composite shield material 4 has high flexibility and bending resistance because it is configured as a composite material of the braided body 41 and the fluid shielding aid 42 .
  • the braided body 41 exhibits high flexibility because it is constructed by weaving a plurality of thin metal wires 41a. Further, the braided body 41 is less likely to be damaged due to metal fatigue even if it is repeatedly bent. Since the shielding aid 42 is composed of a substance having fluidity, it follows the bending of the braided body 41 well, and maintains the liquid film formed state, etc., and the inside of the braided body 41 and/or or remain held to the surface and also to the area around the braid 41 .
  • the shielding aid 42 Even if the amount of the shielding aid 42 is reduced due to a temporary discontinuity of the liquid film during the bending motion of the braided body 41, the shielding aid 42 will be removed when the bending motion is completed. The liquidity allows it to spread again and return to a state of spreading over a wide area. Therefore, even if the composite shield material 4 is repeatedly bent, the state in which the noise shielding property of the composite shield material 4 is enhanced by the shield auxiliary agent 42 is stably maintained. Further, since the shielding aid 42 is composed of a material having fluidity and has almost no rigidity, even if the composite shielding material 4 held by the braided body 41 is bent, the shielding aid is Substantially no stress buildup due to deformation occurs in agent 42 . Therefore, even if the shielding material 4 is repeatedly bent, damage to the shielding aid 42 is unlikely to occur, and the damage will not progress further.
  • both the braided body 41 and the shielding aid 42 have high flexibility, so that the composite shield material 4 as a whole has high flexibility. Even if the communication member such as the communication wire 1 on which the composite shield material 4 is arranged is repeatedly bent, the high noise shielding performance of the composite shield material 4 is stably maintained.
  • the shielding aid 42 having flowability, a solid substance containing a conductive material (including an elastic body such as a rubber-like substance and a solid substance having flexibility such as a gel-like substance) can be used. It is also conceivable to combine the braided body 41 and the braided body 41 by bonding or the like to assist the noise shielding performance of the braided body 41 .
  • the composite shield material 4 containing the shielding aid 42 is laminated with the metal foil 3, and the composite shield material 4 shields noise accompanying damage to the metal foil 3 due to bending. It can also play a role in compensating for performance degradation. If the metal foil 3 is repeatedly bent as the communication wire 1 is bent, there is a possibility that the metal foil 3 will be damaged, such as broken, due to metal fatigue. At this time, if a crack occurs in the metal foil 3, the noise shielding property of the metal foil 3 may be impaired due to transmission of electromagnetic waves through the crack. In particular, it becomes difficult to confine the electromagnetic field generated from the core wire 2 inside the metal foil 3 . In addition, the noise shielding performance tends to deteriorate especially in a high frequency range.
  • the composite shield material 4 containing the shielding aid 42 and having high bending resistance is provided on the outer periphery of the metal foil 3, and the metal foil 3 is damaged by bending. Even so, the composite shielding material 4 maintains the high noise shielding property of the communication wire 1 as a whole. Even if a crack occurs in the metal foil 3 due to damage, the shielding aid 42 having fluidity spreads just outside the crack while being held by the braided body 41, so that the opening of the crack can be formed into the braided body 41. This is because the braided body 41 and the shielding aid 42 suppress transmission of electromagnetic waves through the cracks in the metal foil 3 .
  • the specific viscosity of the shielding aid 42 is not particularly limited as long as it has fluidity. However, from the viewpoint of stably holding the shielding agent 42 by the braided body 41 and forming a highly continuous liquid film with the shielding agent 42 including the portion that fills or covers the gap S between the metal wires 41a. , the shielding aid 42 preferably has a certain degree of viscosity. Specifically, the shielding aid 42 is preferably viscous (paste, semi-liquid). As a result, the shielding aid 42 can be stably held in the interior, surface, and peripheral regions of the braided body 41, including the space S between the metal wires 41a. Even after bending, it becomes easy to maintain the stably held state.
  • the viscosity of the shielding aid 42 is preferably 5 mPa ⁇ s or more, more preferably 10 mPa ⁇ s or more, or 100 mPa ⁇ s or more.
  • the viscosity of the shielding aid 42 is preferably 1000 mPa ⁇ s or less, more preferably 500 mPa ⁇ s or less.
  • the type and component composition of the shielding aid 42 are not particularly limited as long as it contains a conductive substance and is configured as a fluid material.
  • the shielding aid 42 may be configured as a composite material in which a powder material is dispersed and which is fluid at room temperature as a whole. The latter form, in which the conductive substance powder is dispersed in the dispersion medium, is preferable from the viewpoint of availability, versatility, and the like.
  • the dispersion medium may be conductive or non-conductive, but is preferably non-conductive from the viewpoint of availability and versatility.
  • it is preferably a non-conductive organic dispersion medium.
  • the powder of the conductive substance dispersed in the dispersion medium may be composed of a powder of a non-metallic conductor such as a carbon material such as graphite or carbon black, or a conductive oxide. From the point of view, it is preferable to be configured as a metal powder.
  • any organic substance that has fluidity at room temperature and low volatility can be used.
  • various compounds can be applied.
  • hydrocarbon-based, ester-based, ether-based, ketone-based, alcohol-based, and halogenated hydrocarbon-based low-volatile or non-volatile organic solvents, liquid polymers such as liquid resins and liquid rubbers, etc. can be preferably used. can be done.
  • the dispersion medium preferably has a certain degree of viscosity in that the viscous shielding aid 42 can be easily applied when the powder of the conductive substance is dispersed in the dispersion medium.
  • the viscosity of the dispersion medium is preferably 5 mPa ⁇ s or more and 50 mPa ⁇ s or less.
  • an ester-based organic solvent such as a trimellitate ester, polyethylene glycol, or the like can be suitably used. can.
  • trimellitate include tris(2-ethylhexyl) trimellitate (TOTM).
  • the dispersion medium only one substance may be used, or a mixture of two or more substances may be used.
  • the metal species constituting the metal powder dispersed in the dispersion medium in the shielding aid 42 is also not particularly limited. It is preferably a metal with high magnetic properties, and may be a non-magnetic metal. Copper, aluminum, silver, gold, iron, cobalt, zinc, or alloys thereof can be preferably exemplified. Among them, copper or a copper alloy can be preferably used from the viewpoint of high conductivity and versatility. As the metal powder, only one type may be used, or two or more types may be mixed and used. Although the particle size of the metal powder is not particularly limited, it is preferably 20 ⁇ m or more from the viewpoint of exhibiting a high noise shielding effect.
  • the thickness is preferably 100 ⁇ m or less.
  • the particle shape of the metal powder is not particularly limited, either, and any particle shape such as a spherical shape, a flat shape, and an amorphous shape can be used.
  • the metal powder may have a layer of a metal compound such as an oxide on the surface, and may be surface-treated with an organic molecule or the like as appropriate.
  • the content of the metal powder in the shielding aid 42 is not particularly limited, but from the viewpoint of exhibiting sufficient noise shielding performance, etc., it is 80% by mass or more when the entire shielding aid 42 is 100% by mass. is preferred. Moreover, it is preferable that it is 38 volume% or more assuming that the whole shield auxiliary agent 42 is 100 volume%. On the other hand, from the viewpoint of securing the flexibility of the shielding aid 42, enhancing the bending resistance, and securing the fluidity of the shielding aid 42, the content of the metal powder should be 98% by mass or less and 85% by volume. % or less. As the content of the metal powder in the shielding aid 42 increases, the conductivity of the shielding aid 42 as a whole increases.
  • the metal powder dispersed in the dispersion medium contacts between the particles, and along the axial direction of the communication wire 1, the metal particles form a conductive path. Even if the amount of metal powder is not contained, the shielding aid 42 having sufficiently high noise shielding performance can be constructed. This is because at least part of the metal powder contained in the shielding aid 42 is in contact with the metal wires 41a forming the braided body 41, and is kept at the same potential as the braided body 41 connected to the ground potential.
  • the shielding aid 42 may contain additives as appropriate as long as they do not significantly affect the properties of the shielding aid 42 and its constituent components, such as fluidity and conductivity.
  • additives include stabilizers, antioxidants, copper damage inhibitors, lubricants, and the like.
  • the braid density in the braided body 41 constituting the composite shield material 4 is not particularly limited, but is preferably 50% or more. Then, due to the noise shielding effect of the metal wire 41a itself and the effect that the shielding aid 42 can be stably held in the form of a liquid film or the like in the portion including the gap S between the metal wires 41a, the composite shield material 4 is formed. has high noise shielding performance.
  • the braid density of the braided body 41 is preferably 95% or less. As a result, the composite shield material 4 can be made flexible and lightweight. Furthermore, from the viewpoint of reducing the weight and diameter of the communication wire 1, the braid density is preferably 80% or less.
  • Braid densities of 95% or less and 80% or less are lower than the braid densities of braided shields generally applied to communication wires 1. Since not only the wire 41a but also the shielding aid 42 contributes to noise shielding, even if the braided body 41 has a low braid density, the composite shield material 4 as a whole can exhibit sufficiently high noise shielding performance. In addition, since the shielding aid 42 is composed of a material having fluidity and can form a liquid film by surface tension and viscosity, even if the braid density is low and the width of the gap S between the metal wires 41a is wide to some extent, , the gap S can be closed by forming a liquid film, and transmission of electromagnetic waves through the gap S can be suppressed.
  • the shielding aid 42 is obtained by knitting the metal wires 41a to form the braided body 41, and then bringing the shielding aid 42 into contact with the formed braided body 41 by coating, dripping, immersion, or the like. and can be manufactured.
  • the shielding aid 42 is placed in the form of a liquid film or the like on the outer circumference of the metal wire 41a, which is the raw material of the braided body 41, by coating, dripping, immersion, or the like, and the metal wire 41a in that state is braided.
  • the composite shield material 4 can be manufactured.
  • the fluidity of the shielding aid 42 allows the shielding aid 42 arranged around the outer periphery of the metal wire 41a to spread even into the gap S corresponding to the region not occupied by the metal wire 41a.
  • the braided body 41 constituting the composite shield material 4 is formed by braiding the metal wires 41a into a hollow tubular shape around the outer circumference of the core wire 2 coated with the metal foil 3 in the communication wire 1. is continuously formed, the latter form, that is, the method of arranging the shielding aid 42 on the outer circumference of the metal wire 41a and then braiding the metal wire 41a into a braided structure can be preferably adopted. .
  • the continuous shield material 4 can be easily formed. can be done.
  • a coaxial communication wire was produced, which was equipped with a composite shielding material containing a braid and a shielding aid.
  • a core wire having an insulating layer made of polypropylene formed on the outer periphery of a conductor configured as a copper alloy stranded wire was covered, and metal foils were arranged in a vertical manner.
  • a copper thin film with a thickness of 9 ⁇ m and a PET film with a thickness of 16 ⁇ m were bonded with an adhesive layer with a thickness of 1 ⁇ m or less.
  • a composite shield material was formed on the outside of the metal foil placed around the core wire.
  • a composite shield material containing the braided body and the shielding aid was formed by forming a braided structure by braiding the metal wires into a hollow cylindrical shape around the outer periphery of the metal foil while immersing the metal wires in the shielding aid.
  • TA wire tin-plated annealed copper wire
  • the braid density was 58%.
  • Copper powder having a particle size of 0.3 to 5.0 ⁇ m dispersed in trimellitate ester (TOTM) was used as the shield aid.
  • the content of the copper powder was 95% by mass (68% by volume) with respect to the entire shielding aid.
  • This shield adjuvant was viscous.
  • a communication wire of sample 1 was obtained by forming a sheath layer on the outer periphery of the composite shield material.
  • the constituent materials of the sheath layer are 90 parts by mass of olefinic thermoplastic elastomer (TPO), 10 parts by mass of styrene thermoplastic elastomer (SEBS), 2 parts by mass of antioxidant, and magnesium hydroxide as a flame retardant.
  • TPO olefinic thermoplastic elastomer
  • SEBS styrene thermoplastic elastomer
  • antioxidant antioxidant
  • magnesium hydroxide as a flame retardant.
  • One containing 120 parts by mass was used.
  • sample 2 a coaxial communication wire was produced, which was equipped with a normal braided body, which was not compounded with a shielding aid, as a shielding material.
  • a shielding aid as a shielding material.
  • they were braided into a braided structure to obtain Sample 2 of the communication wire.
  • ⁇ Evaluation method> The noise shielding properties of the communication wires of Samples 1 and 2 were evaluated.
  • a radiated emission evaluation based on CISPR25 was performed. Specifically, in the anechoic chamber, a horn antenna was installed at a position laterally separated by 1.0 m from the central portion of the communication wire cut to 1500 mm. Then, an electrical signal with a frequency of 1.6 GHz was input to the communication wire, and the amount of noise radiation at this time was measured by a horn antenna. A case where the amount of noise emission was less than 24 dB ( ⁇ V/m) was evaluated as high noise shielding (A). On the other hand, when the noise radiation amount was 24 dB ( ⁇ V/m) or more, the noise shielding property was evaluated as low (B).
  • Table 1 shows the evaluation results of the noise shielding properties of Samples 1 and 2 before and after the bending test.

Abstract

Provided are a shielding material which has a high bending resistance and which is capable of maintaining a high noise shielding effect even if repeatedly bent, and a communication cable provided with such a shielding material. A shielding material 4 comprises: a braided body 41 obtained by braiding a plurality of metal wires 41a; and a shielding aid 42 which has fluidity and which includes an electrically conductive material, and which is disposed in contact with the braided body 41. Further, the communication cable includes: a core wire comprising a conductor and an insulating layer covering an outer periphery of the conductor; and the shielding material 4 covering an outer periphery of the core wire.

Description

シールド材および通信用電線Shielding materials and communication wires
 本開示は、シールド材および通信用電線に関する。 The present disclosure relates to shielding materials and communication wires.
 通信用電線をはじめとする通信用部材には、シールド材が設けられることが多い。シールド材は、外部からその通信用部材に侵入する電磁波を遮蔽し、通信用部材におけるノイズの発生を抑制する。また、シールド材は、通信用部材から外部へ放出される電磁波を遮蔽し、放出された電磁波が外部においてノイズの原因となるのを抑制する役割も果たす。その種のシールド材として、複数の金属素線を相互に編み込んだ編組体がしばしば用いられる。編組体は高い耐屈曲性を有するため、通信用電線のように、屈曲を伴う用途に使用される通信用部材に設けるシールド材として、好適である。例えば、特許文献1に、耐屈曲信号伝送ケーブルとして、複数の同軸信号線をカッド構造になるように束ねたカッド同軸構造線と、カッド同軸構造線の周囲を被覆する絶縁テープと、絶縁テープの外周に配置される金属網(編組体)と、前記金属網を被覆する絶縁外被と、を備えた構造が開示されている。 Communication components such as communication wires are often provided with shielding materials. The shield material shields electromagnetic waves entering the communication member from the outside and suppresses noise generation in the communication member. In addition, the shield material shields electromagnetic waves emitted from the communication member to the outside, and also plays a role of suppressing the emitted electromagnetic waves from causing noise outside. A braided body in which a plurality of metal wires are interwoven is often used as such a shield material. Since the braided body has high bending resistance, it is suitable as a shielding material provided for a communication member used in applications involving bending, such as a communication wire. For example, in Patent Document 1, as a bending-resistant signal transmission cable, a quad coaxial structure line in which a plurality of coaxial signal lines are bundled so as to form a quad structure, an insulating tape covering the circumference of the quad coaxial structure line, and an insulating tape. A structure is disclosed that includes a metal mesh (braid) arranged on the outer periphery and an insulating jacket that covers the metal mesh.
特開2008-34341号公報JP-A-2008-34341 特開2020-021556号公報JP 2020-021556 A 特開2004-214062号公報Japanese Patent Application Laid-Open No. 2004-214062 特開2016-24953号公報JP 2016-24953 A
 上記のように、金属素線を編み込んだ編組体は、通信用電線等の通信用部材におけるシールド材として好適に用いることができる。しかし、編組体は、その編目構造に由来して、金属素線の間に空隙を有しているため、高周波(短波長)の電磁波であれば空隙を通過することができ、高周波の電磁波を十分に遮蔽するのが難しい場合がある。しかし、自動車分野等において、通信用電線を用いた通信が高速化しており、シールド材を用いて、高周波数域でもノイズの影響を効果的に低減することが求められる。 As described above, a braided body in which metal wires are woven can be suitably used as a shielding material for communication members such as communication wires. However, since the braided body has gaps between the metal wires due to its mesh structure, high-frequency (short wavelength) electromagnetic waves can pass through the gaps, and high-frequency electromagnetic waves can pass through the gaps. Adequate shielding can be difficult. However, in the field of automobiles and the like, the speed of communication using communication wires is increasing, and it is required to effectively reduce the influence of noise even in a high frequency range using a shielding material.
 例えば、通信用電線において、金属素線よりなる編組体に加えて、金属箔をコア線の外周に配置し、電磁波遮蔽効果の向上が図られる場合がある。しかし金属箔は、一般には編組体ほど高い耐屈曲性を有さず、通信用電線が繰り返して屈曲を受けた場合等に、金属疲労によって金属箔に破断が生じる場合がある。すると、破断によって生じた金属箔の割れ目を電磁波が通過することで、十分なノイズ遮蔽効果が得られなくなる可能性がある。金属箔以外にも、電磁波の透過を低減することができる編組体以外の部材を、編組体と合わせて用いることで、高周波域におけるノイズ遮蔽効果を高めることも考えられるが、その部材が十分に高い耐屈曲性を有するものでないと、上記金属箔の場合と同様に、通信用電線の屈曲を経た際に、十分なノイズ遮蔽効果を維持しきれない可能性がある。 For example, in a communication wire, in addition to a braided body made of metal wires, metal foil may be placed around the core wire to improve the electromagnetic wave shielding effect. However, the metal foil generally does not have as high bending resistance as the braided body, and the metal foil may break due to metal fatigue when, for example, the communication wire is repeatedly bent. As a result, electromagnetic waves may pass through cracks in the metal foil caused by the breakage, resulting in an insufficient noise shielding effect. In addition to metal foil, it is conceivable to use a member other than the braided body that can reduce the transmission of electromagnetic waves in combination with the braided body to enhance the noise shielding effect in the high frequency range. If it does not have high bending resistance, it may not be possible to maintain a sufficient noise shielding effect when the communication wire is bent, as in the case of the metal foil.
 以上に鑑み、高い耐屈曲性を有し、繰り返して屈曲を受けても、高いノイズ遮蔽効果を維持することができるシールド材、およびそのようなシールド材を備えた通信用電線を提供することを課題とする。 In view of the above, it is desirable to provide a shielding material that has high bending resistance and can maintain a high noise shielding effect even when subjected to repeated bending, and a communication wire provided with such a shielding material. Make it an issue.
 本開示にかかるシールド材は、複数の金属素線を編み込んだ編組体と、流動性を有し、かつ導電性材料を含み、前記編組体に接触して配置されたシールド補助剤と、を有する。本開示にかかる通信用電線は、導体と、前記導体の外周を被覆する絶縁層と、を有するコア線と、前記コア線の外周を被覆する前記シールド材と、を有する。 The shield material according to the present disclosure includes a braided body in which a plurality of metal wires are woven, and a shielding aid that has fluidity and contains a conductive material and is arranged in contact with the braided body. . A communication wire according to the present disclosure includes a core wire having a conductor, an insulating layer covering the outer circumference of the conductor, and the shield material covering the outer circumference of the core wire.
 本開示にかかるシールド材および通信用電線は、高い耐屈曲性を有し、繰り返して屈曲を受けても、高いノイズ遮蔽効果を維持することができるシールド材、およびそのようなシールド材を備えた通信用電線となる。 The shielding material and the communication wire according to the present disclosure have high bending resistance and can maintain a high noise shielding effect even when subjected to repeated bending, and such a shielding material It becomes a communication wire.
図1A,1Bは、本開示の一実施形態にかかる通信用電線を示す図であり、それぞれ斜視図、および軸線方向に垂直に切断した断面図である。1A and 1B are diagrams showing a communication wire according to an embodiment of the present disclosure, which are a perspective view and a cross-sectional view taken perpendicularly to the axial direction, respectively. 図2Aは、本開示の一実施形態にかかるシールド材を構成する編組体を示す平面図である。図2Bは、図2AのA-A断面に対応するシールド材の断面図であり、編組体とシールド補助剤とを含んでいる。FIG. 2A is a plan view showing a braid that constitutes a shield material according to an embodiment of the present disclosure; FIG. FIG. 2B is a cross-sectional view of the shielding material corresponding to cross-section AA of FIG. 2A, including the braid and the shielding aid.
[本開示の実施形態の説明]
 最初に、本開示の実施態様を説明する。
 本開示にかかるシールド材は、複数の金属素線を編み込んだ編組体と、流動性を有し、かつ導電性材料を含み、前記編組体に接触して配置されたシールド補助剤と、を有する。
[Description of Embodiments of the Present Disclosure]
First, embodiments of the present disclosure will be described.
The shield material according to the present disclosure includes a braided body in which a plurality of metal wires are woven, and a shielding aid that has fluidity and contains a conductive material and is arranged in contact with the braided body. .
 上記シールド材は、編組体に加え、導電性材料を含むシールド補助剤を有するため、シールド補助剤に含まれる導電性材料の寄与により、高いノイズ遮蔽性を有するものとなる。シールド補助剤が、流動性を有する材料として構成されていることで、編組体の金属素線間の空隙を含め、編組体の内部や表面、また編組体の周辺の領域にシールド補助剤が広がって分布した状態をとりやすく、さらにシールド材が屈曲を受けた場合にも、その広がって分布した状態を維持することができる。よって、シールド補助剤が編組体によるノイズ遮蔽性を効果的に補助することができ、さらに、シールド材の屈曲を経ても、その効果が維持される。金属箔等、シールド材に隣接して設けられる他のノイズ遮蔽用部材が屈曲によって損傷を起こした場合でも、シールド補助剤がその損傷に起因するノイズ遮蔽性の低下を補うことができる。さらに、シールド補助剤が流動性を有する材料として構成されることで、固体の材料である場合とは異なり、屈曲を受けても、負荷の蓄積や、損傷によるシールド性能の低下を起こしにくい。このように、シールド材が、高い耐屈曲性を有するものとなり、繰り返して屈曲を受けても、高いノイズ遮蔽効果を維持することができる。 In addition to the braided body, the above shield material has a shielding aid containing a conductive material, so it has high noise shielding properties due to the contribution of the conductive material contained in the shielding aid. Since the shielding aid is composed of a fluid material, the shielding aid spreads over the inside and surface of the braided body, including the gaps between the metal wires of the braided body, and the area around the braided body. In addition, even when the shield material is bent, the spread and distributed state can be maintained. Therefore, the shield auxiliary agent can effectively assist the noise shielding property of the braided body, and the effect is maintained even after bending of the shield material. Even if another noise shielding member provided adjacent to the shielding material, such as a metal foil, is damaged due to bending, the shielding aid can compensate for the deterioration of noise shielding properties caused by the damage. Furthermore, since the shielding aid is composed of a material having fluidity, unlike the case where the shielding aid is made of a solid material, it is less likely that the shielding performance will deteriorate due to accumulation of load or damage even when subjected to flexing. In this way, the shield material has high bending resistance, and can maintain a high noise shielding effect even after being repeatedly bent.
 ここで、前記シールド補助剤は、前記編組体を構成する前記複数の金属素線の間の空隙に充填された状態、および前記空隙を被覆する状態、の少なくとも一方をとっているとよい。すると、編組体において、金属素線に占められていない空隙が、導電性材料を含むシールド補助剤によって閉塞されることになる。その結果、編組体の空隙を介して電磁波が透過しにくくなり、シールド材によって、高周波数域においても電磁波の透過を効率的に抑制し、高いノイズ遮蔽性を得ることができる。 Here, it is preferable that the shielding aid is in at least one of a state in which the voids between the plurality of metal wires constituting the braided body are filled, and a state in which the voids are covered. Then, in the braided body, the voids not occupied by the metal wires are blocked by the shielding aid containing the conductive material. As a result, it becomes difficult for electromagnetic waves to pass through the voids of the braided body, and the shielding material can efficiently suppress the transmission of electromagnetic waves even in a high frequency range, and high noise shielding properties can be obtained.
 前記シールド補助剤は、粘液状であるとよい。すると、シールド材において、シールド補助剤が、金属素線間の空隙に充填された状態、または空隙を被覆した状態等、編組体に保持された状態に留まりやすくなる。その結果、シールド材が、繰り返して屈曲を受けても、シールド補助剤の効果によって高いノイズ遮蔽性を示す状態を維持しやすくなる。 The shield adjuvant is preferably mucus-like. Then, in the shielding material, the shielding aid tends to stay in a state of being held by the braid, such as a state in which the gaps between the metal wires are filled or a state in which the gaps are covered. As a result, even if the shielding material is repeatedly bent, it becomes easier to maintain a state of exhibiting high noise shielding properties due to the effect of the shielding aid.
 前記シールド補助剤は、前記導電性材料としての金属粉末と、前記金属粉末を分散させる非導電性の分散媒と、を含んでいるとよい。すると、流動性を有し、かつ導電性材料を含んだシールド補助剤を、簡便に調製して利用することができる。また、シールド補助剤が、高いノイズ遮蔽性向上効果を示すものとなる。 The shielding aid preferably contains metal powder as the conductive material and a non-conductive dispersion medium for dispersing the metal powder. As a result, a fluid shielding aid containing a conductive material can be easily prepared and used. In addition, the shield aid exhibits a high effect of improving noise shielding properties.
 前記シールド補助剤における前記金属粉末の含有量は、80質量%以上、98質量%以下であるとよい。すると、シールド材において、シールド補助剤が高いノイズ遮蔽性向上効果を示すとともに、シールド補助剤の流動性の低下等、多量の金属粉末の使用による影響を低減することができる。 The content of the metal powder in the shielding aid is preferably 80% by mass or more and 98% by mass or less. As a result, in the shielding material, the shielding aid exhibits a high effect of improving noise shielding properties, and the effects of using a large amount of metal powder, such as a decrease in fluidity of the shielding aid, can be reduced.
 前記編組体の編組密度は、50%以上、95%以下であるとよい。すると、シールド材において、高いシールド遮蔽性を得るとともに、編組体を構成する金属素線の量を低減することができる。本開示にかかるシールド材においてはシールド補助剤の流動性により、金属素線間の空隙の箇所を含めて、編組体の広い領域にシールド補助剤が行き渡って分布するため、金属素線の密度がある程度低くても、十分なノイズ遮蔽性を発揮することができる。特に編組密度が80%以下であることが好ましい。 The braid density of the braided body is preferably 50% or more and 95% or less. As a result, it is possible to obtain a high shielding performance in the shield material and reduce the amount of the metal wires forming the braided body. In the shield material according to the present disclosure, due to the fluidity of the shielding aid, the shielding aid is distributed over a wide area of the braided body, including the gaps between the metal wires, so the density of the metal wires is increased. Even if it is low to some extent, sufficient noise shielding properties can be exhibited. In particular, it is preferable that the braid density is 80% or less.
 本開示にかかる通信用電線は、導体と、前記導体の外周を被覆する絶縁層と、を有するコア線と、前記コア線の外周を被覆する前記シールド材と、を有する。 A communication wire according to the present disclosure includes a core wire having a conductor and an insulating layer covering the outer circumference of the conductor, and the shield material covering the outer circumference of the core wire.
 上記通信用電線においては、コア線の外周に、編組体とシールド補助剤を含むシールド材が配置されており、シールド材によって、コア線に侵入する電磁波、およびコア線から放出される電磁波が低減され、高いノイズ遮蔽性が得られる。シールド材を構成するシールド補助剤が流動性を有するものであることにより、通信用電線が高い耐屈曲性を有し、屈曲を繰り返しても、シールド材による高いノイズ遮蔽性が維持される。 In the above communication wire, a shield material containing a braid and a shielding aid is arranged around the core wire, and the shield material reduces electromagnetic waves that enter the core wire and electromagnetic waves that are emitted from the core wire. and provide high noise shielding. Since the shielding aid constituting the shielding material has fluidity, the communication wire has high bending resistance, and the shielding material maintains high noise shielding properties even after repeated bending.
 ここで、前記通信用電線はさらに、前記コア線の外周を被覆する金属箔を有し、前記シールド材は、前記金属箔の外周を被覆しているとよい。金属箔は、通信用電線において、上記シールド材とともに、ノイズ遮蔽効果を発揮するものとなる。通信用電線を屈曲させた際に、金属疲労によって金属箔が損傷し、割れ目が生じる可能性もあるが、金属箔の外周に、シールド補助剤を含み、高い耐屈曲性を有するシールド材が配置されているため、金属箔に割れ目が生じた場合でも、その割れ目を介した電磁波の透過を、シールド材によって抑制し、高いノイズ遮蔽性を維持することができる。よって、通信用電線が屈曲に比較的弱い部材である金属箔を含んでいても、通信用電線全体として、高い耐屈曲性を有するものとなる。 Here, preferably, the communication wire further has a metal foil covering the outer periphery of the core wire, and the shield material covers the outer periphery of the metal foil. The metal foil exhibits a noise shielding effect together with the shielding material in the communication wire. When a communication wire is bent, the metal foil may be damaged due to metal fatigue and cracks may occur. Therefore, even if a crack occurs in the metal foil, the shielding material can suppress transmission of electromagnetic waves through the crack, and high noise shielding properties can be maintained. Therefore, even if the communication wire contains metal foil, which is a member that is relatively weak against bending, the communication wire as a whole has high bending resistance.
 前記金属箔の厚さは、15μm以下であるとよい。すると、金属箔の柔軟性が高くなり、繰り返して屈曲を受けても、金属箔に損傷が発生しにくくなる。金属箔が薄くなることで、金属箔によるノイズ遮蔽性は低くなるが、本開示にかかる通信用電線においては、シールド補助剤を含むシールド材が金属箔と合わせて配置されていることで、金属箔を薄くしても、通信用電線全体として、十分なノイズ遮蔽性を確保することができる。 The thickness of the metal foil is preferably 15 μm or less. As a result, the flexibility of the metal foil increases, and the metal foil is less likely to be damaged even if it is repeatedly bent. As the metal foil becomes thinner, the noise shielding property of the metal foil becomes lower. Even if the foil is made thin, it is possible to secure sufficient noise shielding properties for the entire communication wire.
 前記通信用電線はさらに、前記シールド材の外周を被覆するシース層を有するとよい。シース層は、シールド材を保護するものとなる。特に、流動性を有する材料として構成されたシールド補助剤の外部への流出や散逸を防止するものとなる。 The communication wire may further have a sheath layer covering the outer circumference of the shield material. The sheath layer serves to protect the shield material. In particular, it prevents the outflow and dissipation of the shielding aid made of fluid material.
[本開示の実施形態の詳細]
 以下、図面を用いて、本開示の実施形態にかかるシールド材および通信用電線について、詳細に説明する。本明細書において、特記しない限り、各種特性は、室温、大気中における特性を指すものとする。
[Details of the embodiment of the present disclosure]
Shielding materials and communication wires according to embodiments of the present disclosure will be described in detail below with reference to the drawings. In this specification, unless otherwise specified, various properties refer to properties at room temperature in the atmosphere.
 本開示の実施形態にかかるシールド材は、編組体とシールド補助剤とを含むものであり、電磁波の透過を低減することで、電磁波に由来するノイズを抑制するシールド部材として機能する。このシールド材は、種々の通信用部材に適用することができるが、特に通信用電線に好適に適用することができる。本開示の実施形態にかかる通信用電線は、本開示の実施形態にかかるシールド材を備えたものである。以下、通信用電線を中心として、説明を行う。 A shielding material according to an embodiment of the present disclosure includes a braided body and a shielding aid, and functions as a shielding member that suppresses noise derived from electromagnetic waves by reducing transmission of electromagnetic waves. This shield material can be applied to various communication members, and is particularly suitable for communication wires. A communication wire according to an embodiment of the present disclosure includes a shield material according to an embodiment of the present disclosure. In the following, the description will focus on the electric wire for communication.
<通信用電線の構成>
 図1A,1Bに、本開示の一実施形態にかかる通信用電線1の構造を示す。図1Aは斜視図であり、図1Bは通信用電線1を軸線方向に垂直に切断した断面図である。
<Configuration of communication wire>
1A and 1B show the structure of a communication wire 1 according to an embodiment of the present disclosure. 1A is a perspective view, and FIG. 1B is a cross-sectional view of the communication wire 1 cut perpendicularly to the axial direction.
(通信用電線の全体構成)
 通信用電線1は、同軸電線として構成されている。具体的には、通信用電線1は、導体21と、導体21の外周を被覆する絶縁層22とを有するコア線2を備えている。そして、コア線2の外周に、金属箔3が設けられている。金属箔3の外周を被覆して、本開示の一実施形態にかかるシールド材(複合シールド材)4が設けられている。さらに、複合シールド材4の外周を被覆して、シース層5が設けられている。
(Overall configuration of communication wire)
The communication wire 1 is configured as a coaxial wire. Specifically, the communication wire 1 includes a core wire 2 having a conductor 21 and an insulating layer 22 covering the outer circumference of the conductor 21 . A metal foil 3 is provided around the core wire 2 . A shield material (composite shield material) 4 according to an embodiment of the present disclosure is provided to cover the outer periphery of the metal foil 3 . Furthermore, a sheath layer 5 is provided to cover the outer circumference of the composite shield material 4 .
 コア線2の外周に、金属箔3と複合シールド材4を有する同軸電線として構成された上記のような通信用電線1は、1GHz以上の高周波域の信号を伝送するのに、好適に用いることができる。しかし、本開示にかかる通信用電線1は、コア線2の外側を包囲して、複合シールド材4が設けられるものであれば、上記のような構造を有するものに限られず、通信周波数や用途に応じた構成を採用すればよい。例えば、上記の同軸型の形態では、コア線2として、導体21と被覆層22を備えた絶縁電線を単独で用いているが、複数の絶縁電線を用いてもよい。例えば、1対の絶縁電線を、相互に撚り合わせるか、並走させるかして、差動信号を伝送するように、コア線2を構成することができる。特許文献1に示されるように、4本の絶縁電線を含むカッド構造としてコア線2を構成してもよい。また、ノイズの影響がそれほど大きくない場合や、通信周波数が、例えば1MHz以下のように比較的低い場合等には、金属箔3を省略してもよい。さらに、上記の形態では、説明した各層を、それぞれ内側の構成層の外周に直接接触させて形成しているが、通信用電線1は、上記で説明した各層以外の構成層を、適宜含むものであってもよい。ただし、金属箔3と複合シールド材4は、間に別の構成層を介さずに、直接接触していることが好ましい。以下、上記で例示した同軸型の通信用電線1の各構成部材について説明する。 The above-described communication wire 1 configured as a coaxial wire having a metal foil 3 and a composite shielding material 4 on the outer periphery of the core wire 2 is suitable for transmitting signals in a high frequency range of 1 GHz or higher. can be done. However, the communication wire 1 according to the present disclosure is not limited to having the above structure as long as it surrounds the outer side of the core wire 2 and is provided with the composite shield material 4. A configuration corresponding to the For example, in the coaxial configuration described above, an insulated wire including the conductor 21 and the covering layer 22 is used alone as the core wire 2, but a plurality of insulated wires may be used. For example, the core wire 2 can be configured such that a pair of insulated wires are twisted together or run in parallel to transmit a differential signal. As shown in Patent Document 1, the core wire 2 may be configured as a quad structure including four insulated wires. Moreover, the metal foil 3 may be omitted when the influence of noise is not so great, or when the communication frequency is relatively low, for example, 1 MHz or less. Furthermore, in the above embodiment, each of the layers described above is formed in direct contact with the outer periphery of the inner constituent layer, but the communication wire 1 may appropriately include constituent layers other than the layers described above. may be However, it is preferable that the metal foil 3 and the composite shielding material 4 are in direct contact with each other without intervening another constituent layer. Each constituent member of the coaxial communication wire 1 exemplified above will be described below.
 コア線2は、通信用電線1において、電気信号の伝送を担う信号線であり、導体21と、導体21の外周を被覆する絶縁層22とを有している。導体21および絶縁層22を構成する材料は、特に限定されるものではない。導体21を構成する材料としては、種々の金属材料を用いることができるが、高い導電性を有する等の点から、銅または銅合金を用いることが好ましい。導体21は、単線として構成されてもよいが、屈曲時の柔軟性を高める等の観点から、複数の素線(例えば7本)が撚り合わせられた撚線として構成されることが好ましい。絶縁層22は、コア線2において、導体21を絶縁するものであり、有機ポリマーを含む材料より構成される。有機ポリマーの種類は、特に限定されるものではなく、ポリオレフィンやオレフィン系共重合体等のオレフィン系ポリマー、ポリ塩化ビニル等のハロゲン系ポリマー、各種エンジニアリングプラスチック、エラストマー、ゴム等を挙げることができる。絶縁層22には、有機ポリマーに加えて、適宜添加剤が含有されてもよい。 The core wire 2 is a signal wire responsible for transmission of electrical signals in the communication wire 1 and has a conductor 21 and an insulating layer 22 covering the outer circumference of the conductor 21 . The material forming the conductor 21 and the insulating layer 22 is not particularly limited. Various metal materials can be used as a material for the conductor 21, but copper or a copper alloy is preferably used because of its high conductivity. The conductor 21 may be configured as a single wire, but is preferably configured as a stranded wire in which a plurality of strands (for example, seven wires) are twisted together from the viewpoint of increasing flexibility when bending. The insulating layer 22 insulates the conductor 21 in the core wire 2 and is made of a material containing an organic polymer. The type of organic polymer is not particularly limited, and examples include olefin polymers such as polyolefins and olefin copolymers, halogen polymers such as polyvinyl chloride, various engineering plastics, elastomers, and rubbers. The insulating layer 22 may contain additives as appropriate in addition to the organic polymer.
 金属箔3は、金属材料の薄膜として構成されている。金属箔3を構成する金属の種類は、特に限定されるものではなく、銅、銅合金、アルミニウム、アルミニウム合金等を例示することができる。金属箔3は、単一の金属種より構成されても、2種以上の金属種の層が積層されてもよい。また、金属箔3は、独立した金属薄膜よりなる形態のほか、高分子フィルム等の基材に、蒸着、めっき、接着等によって金属層が接合されたものであってもよい。金属箔3は、同軸電線構造において、外部導体として、コア線2を伝送される電気信号のリターンパスの機能を果たすとともに、複合シールド材4とともに、コア線2に侵入する電磁波、およびコア線2から放出される電磁波を低減するノイズ遮蔽材として機能する。通信用電線1において、金属箔3は、外側の複合シールド材4と直接接触しており、複合シールド材4を構成する編組体41がグラウンド電位に接続されることで、金属箔3もグラウンド電位に導通される。金属箔3が基材を有する場合には、複合シールド材4との導通を確保する観点から、金属薄膜が設けられた方の面が外側を向くように配置されることが好ましい。金属箔3は、コア線2の外周に、縦添え状に配置しても、横巻き状に配置してもよいが、縦添え状に配置する方が、高いノイズ遮蔽性能が得られる。 The metal foil 3 is configured as a thin film of a metal material. The type of metal forming the metal foil 3 is not particularly limited, and examples thereof include copper, copper alloys, aluminum, aluminum alloys, and the like. The metal foil 3 may be composed of a single kind of metal, or may be a laminate of layers of two or more kinds of metals. The metal foil 3 may be formed of an independent metal thin film, or may be formed by bonding a metal layer to a base material such as a polymer film by vapor deposition, plating, adhesion, or the like. In the coaxial cable structure, the metal foil 3 functions as an outer conductor as a return path for electrical signals transmitted through the core wire 2, and together with the composite shield material 4, prevents electromagnetic waves entering the core wire 2 and the core wire 2. It functions as a noise shield that reduces the electromagnetic waves emitted from. In the communication wire 1, the metal foil 3 is in direct contact with the outer composite shielding material 4, and the braided body 41 constituting the composite shielding material 4 is connected to the ground potential, so that the metal foil 3 is also grounded. is conducted to When the metal foil 3 has a base material, it is preferable that the side on which the metal thin film is provided faces outward from the viewpoint of ensuring conduction with the composite shield material 4 . The metal foil 3 may be arranged vertically or horizontally around the outer periphery of the core wire 2, but arranging it vertically provides higher noise shielding performance.
 金属箔3の厚さは特に限定されるものではないが、十分なノイズ遮蔽性を確保する観点から、1μm以上であることが好ましい。一方、柔軟性を確保し、通信用電線1全体としての耐屈曲性を高める観点から、金属箔3の厚さは、15μm以下、さらには10μm以下であることが好ましい。本実施形態にかかる通信用電線1においては、金属箔3の外側に設けられる複合シールド材4が高いノイズ遮蔽効果を有するので、金属箔3の厚さをこの程度に小さくしても、通信用電線1全体として、十分に高いノイズ遮蔽性を得ることができる。なお、金属箔3が基材を有する場合には、ここに示した厚さは、基材の厚さを含めず、金属薄膜のみの厚さを指す。なお、基材を含めた金属箔3の厚さとしては、30μm以下であることが好ましい。 Although the thickness of the metal foil 3 is not particularly limited, it is preferably 1 μm or more from the viewpoint of ensuring sufficient noise shielding properties. On the other hand, the thickness of the metal foil 3 is preferably 15 μm or less, more preferably 10 μm or less, from the viewpoint of ensuring flexibility and enhancing the bending resistance of the communication wire 1 as a whole. In the communication wire 1 according to the present embodiment, the composite shield material 4 provided outside the metal foil 3 has a high noise shielding effect. A sufficiently high noise shielding property can be obtained for the electric wire 1 as a whole. In addition, when the metal foil 3 has a base material, the thickness shown here does not include the thickness of the base material, and refers to the thickness of the metal thin film only. The thickness of the metal foil 3 including the substrate is preferably 30 μm or less.
 通信用電線1において、金属箔3は必須に設けられるものではなく、通信周波数が、1MHz以下など比較的低周波数域にある場合や、ノイズの影響が深刻でない場合等には、省略してもよい。しかし、金属箔3を設けておけば、複合シールド材4とともに、ノイズ遮蔽部材として、高い効果を発揮する。特に、数百メガヘルツを超える高周波域では、金属箔3によるノイズ遮蔽の効果が大きくなる。 In the communication wire 1, the metal foil 3 is not necessarily provided, and may be omitted when the communication frequency is in a relatively low frequency range such as 1 MHz or less, or when the influence of noise is not serious. good. However, if the metal foil 3 is provided, it exhibits a high effect as a noise shielding member together with the composite shielding material 4 . In particular, in a high frequency range exceeding several hundred megahertz, the effect of noise shielding by the metal foil 3 increases.
 複合シールド材4については、後に詳しく説明するが、複数の金属素線41aよりなる編組体41と、導電性物質を含み、流動性を有する材料として構成されたシールド補助剤42とが複合されたものである。複合シールド材4は、通信用電線1において、コア線2に侵入する電磁波、およびコア線2から放出される電磁波を遮蔽するノイズ遮蔽部材として機能する。通信用電線1の使用時には、複合シールド材4を構成する編組体41が、グラウンド電位に接続される。 The composite shield material 4, which will be described in detail later, is a composite of a braided body 41 made of a plurality of metal wires 41a and a shielding aid 42 containing a conductive substance and configured as a fluid material. It is. The composite shielding material 4 functions as a noise shielding member that shields electromagnetic waves entering the core wire 2 and electromagnetic waves emitted from the core wire 2 in the communication wire 1 . When the communication wire 1 is used, the braided body 41 forming the composite shield material 4 is connected to the ground potential.
 シース層5は、必須に設けられるものではないが、通信用電線1の最外層として配置されることで、内側に配置されたコア線2、金属箔3、複合シールド材4を保護する役割を果たす。特に、シース層5が複合シールド材4の外周を被覆していることで、複合シールド材4に含まれる流動性を有したシールド補助剤42が、通信用電線1の外部に流出したり散逸したりするのを効果的に抑制し、シールド補助剤42を、複合シールド材4に安定に留めることができる。また、通信用電線1の取り扱い性が高くなる。 The sheath layer 5 is not necessarily provided, but by being arranged as the outermost layer of the communication wire 1, the sheath layer 5 serves to protect the core wire 2, the metal foil 3, and the composite shield material 4 arranged inside. Fulfill. In particular, since the sheath layer 5 covers the outer periphery of the composite shield material 4, the fluid shielding aid 42 contained in the composite shield material 4 does not leak or dissipate to the outside of the communication wire 1. The shielding aid 42 can be stably retained on the composite shielding material 4. In addition, the communication wire 1 can be easily handled.
 シース層5は、有機ポリマーを含む材料より構成されている。有機ポリマーの種類は、特に限定されるものではなく、ポリオレフィンやオレフィン系共重合体等のオレフィン系ポリマー、ポリ塩化ビニル等のハロゲン系ポリマー、各種エンジニアリングプラスチック、エラストマー、ゴム等を挙げることができる。シース層5には、有機ポリマーに加えて、適宜添加剤が含有されてもよい。さらに、シース層5には、粉末状の磁性材料、特に粉末状の軟磁性材料が含有されてもよい。すると、通信用電線1において、シース層5が、金属箔3および複合シールド材4とともに、ノイズ遮蔽機能を果たすものとなる。軟磁性材料としては、フェライト等の金属酸化物、鉄(純鉄または少量の炭素を含む鉄)、各種磁性ステンレス鋼やFe-Ni系合金(パーマロイ)等の合金を例示することができる。 The sheath layer 5 is composed of a material containing an organic polymer. The type of organic polymer is not particularly limited, and examples include olefin polymers such as polyolefins and olefin copolymers, halogen polymers such as polyvinyl chloride, various engineering plastics, elastomers, and rubbers. The sheath layer 5 may contain additives as appropriate in addition to the organic polymer. Furthermore, the sheath layer 5 may contain a powdered magnetic material, particularly a powdered soft magnetic material. Then, in the communication wire 1, the sheath layer 5, together with the metal foil 3 and the composite shield material 4, fulfills the noise shielding function. Examples of soft magnetic materials include metal oxides such as ferrite, iron (pure iron or iron containing a small amount of carbon), various magnetic stainless steels, and alloys such as Fe—Ni alloys (permalloy).
(シールド材の詳細)
 上記のように、本開示の実施形態にかかるシールド材(複合シールド材)4は、編組体41と、シールド補助剤42とを含む複合材として構成されている。図2Aに、複合シールド材4を構成する編組体41のみを拡大した平面図を示す。また、図2Bに、図2AのA-A断面図に対応する複合シールド材4の断面図を示す。
(Details of shield material)
As described above, the shield material (composite shield material) 4 according to the embodiment of the present disclosure is configured as a composite material including the braided body 41 and the shield aid 42 . FIG. 2A shows an enlarged plan view of only the braided body 41 constituting the composite shield material 4. As shown in FIG. Also, FIG. 2B shows a cross-sectional view of the composite shield material 4 corresponding to the AA cross-sectional view of FIG. 2A.
複合シールド材4を構成する編組体41は、複数の金属素線41aが相互に編み込まれた構造を有している。つまり、第一の方向に並べられた金属素線41aの群と、第一の方向と異なる第二の方向に並べられた金属素線41aの群とが、相互に交差され、網目状に編み込まれている。編組体41全体としての形状は特に限定されるものではないが、通信用電線1を構成する複合シールド材4においては、編組体41は、中空筒状に編み上げられている。編組体41を構成する金属素線41aの構成材料は、特に限定されるものではないが、銅、銅合金、アルミニウム、アルミニウム合金等の金属材料、あるいはそれら金属材料の表面に、スズ等によってめっきを施したものを例示することができる。編組体41の編組密度、つまり編組体41の面において金属素線41aが占める面積の割合は、後に説明するように、50%以上、また95%以下であることが好ましい。 A braided body 41 forming the composite shield material 4 has a structure in which a plurality of metal wires 41a are woven together. That is, a group of metal wires 41a arranged in a first direction and a group of metal wires 41a arranged in a second direction different from the first direction are intersected with each other and woven into a mesh. is Although the overall shape of the braided body 41 is not particularly limited, in the composite shield material 4 constituting the communication wire 1, the braided body 41 is braided into a hollow tubular shape. The constituent material of the metal wire 41a constituting the braided body 41 is not particularly limited. can be exemplified. The braid density of the braided body 41, that is, the ratio of the area occupied by the metal wires 41a on the surface of the braided body 41 is preferably 50% or more and 95% or less, as will be described later.
 編組体41とともに複合シールド材4を構成するシールド補助剤42は、導電性材料を含む物質として構成されている。そして、シールド補助剤42は、流動性を有している。複合シールド材4において、シールド補助剤42は、編組体41に接触して配置されている。ここで、シールド補助剤42が流動性を有しているとは、室温において、編組体41に対して一定の形状および位置に固定されず、不定形状をとって移動可能な状態を指す。おおむね、シールド補助剤42の粘度にして、25℃において10000mPa・s以下である。シールド補助剤42は、流動性を有し、導電性材料を含んでいれば(シールド補助剤42全体が流動性を有する導電性物質よりなる場合も含む)、どのような物質より構成されていてもよいが、後に詳しく説明するように、分散媒に金属粉末が分散されたものを、好適に例示することができる。 The shielding aid 42 that constitutes the composite shielding material 4 together with the braided body 41 is configured as a substance containing a conductive material. The shield aid 42 has fluidity. In the composite shield material 4 , the shielding aid 42 is arranged in contact with the braided body 41 . Here, the fact that the shielding aid 42 has fluidity refers to a state in which it is not fixed in a fixed shape and position with respect to the braided body 41 at room temperature and can take an irregular shape and move. In general, the viscosity of the shielding aid 42 is 10000 mPa·s or less at 25°C. The shielding aid 42 may be composed of any material as long as it contains a fluid and conductive material (including the case where the entire shielding aid 42 is composed of a fluid, electrically conductive material). However, as will be described in detail later, a preferred example is one in which metal powder is dispersed in a dispersion medium.
 複合シールド材4において、シールド補助剤42は、編組体41に接触していれば、どのような配置をとっても構わないが、編組体41の内部および/または表面に、広がって分布している。さらに、シールド補助剤42は、編組体41の周辺の領域(通信用電線1の場合は金属箔3とシース層5に挟まれた領域)にまで、広がって分布していてもよい。シールド補助剤42は、図2Bに示すように、編組体41を構成する複数の金属素線41aの間の空隙Sに充填された状態をとっていることが好ましい。あるいは、編組体41の表面に配置されたシールド補助剤42が、空隙Sを被覆する状態をとっていてもよい。シールド補助剤42は、空隙Sに充填された部位と、空隙Sを被覆する部位を両方有していてもよい。また、図2Bに示した形態のように、隣接する空隙Sを充填または被覆する箇所どうしで、シールド補助剤42が、編組体41の表面を被覆する部位を介して、連続していてもよい。シールド補助剤42が、編組体41の間の空隙Sを充填および/または被覆することで、その空隙Sが、外部の空間に対して、シールド補助剤42によって閉塞されることになる。なお、複合シールド材4を作製し、通信用電線1に配置した初期状態において、シールド補助剤42が編組体41の空隙Sを充填または被覆していなくても、シールド補助剤42が流動性を有していることで、徐々に編組体41の内部および表面においてシールド補助剤42が濡れ広がり、空隙Sを充填および/または被覆する状態となりうる。 In the composite shield material 4 , the shielding aid 42 may be placed in any arrangement as long as it is in contact with the braided body 41 , but is spread and distributed inside and/or on the surface of the braided body 41 . Further, the shielding aid 42 may be spread and distributed to the area around the braided body 41 (in the case of the communication wire 1, the area sandwiched between the metal foil 3 and the sheath layer 5). As shown in FIG. 2B, the shielding aid 42 preferably fills the gaps S between the plurality of metal wires 41a forming the braided body 41. As shown in FIG. Alternatively, the shielding aid 42 placed on the surface of the braided body 41 may cover the voids S. The shielding aid 42 may have both a portion filled in the gap S and a portion covering the gap S. Further, as in the form shown in FIG. 2B , the shielding aid 42 may be continuous through the portion covering the surface of the braided body 41 between the portions that fill or cover the adjacent voids S. . The shielding aid 42 fills and/or covers the gaps S between the braids 41 so that the gaps S are blocked from the external space by the shielding aid 42 . In the initial state in which the composite shield material 4 is manufactured and arranged on the communication wire 1, even if the shielding aid 42 does not fill or cover the voids S of the braided body 41, the shielding aid 42 does not have fluidity. As a result, the shielding aid 42 gradually spreads over the interior and surface of the braided body 41, filling and/or covering the voids S. As shown in FIG.
 シールド補助剤42は導電性材料を含んでおり、導電性材料の寄与により、電磁波を遮蔽し、電磁波の透過を低減することができる。また、シールド補助剤42が編組体41と接触していることにより、シールド補助剤42中の導電性材料と編組体41との間に導通が形成され、電磁波を遮蔽する際に生じる電流を、編組体41を介してグラウンド電位に逃がすことができる。よって、シールド補助剤42は、編組体41および金属箔3のノイズ遮蔽性能を補助するノイズ遮蔽材として機能する。このように、複合シールド材4が編組体41に加えてシールド補助剤42を含むことにより、編組体41のみを用いる場合よりも、高いノイズ遮蔽効果が得られる。 The shielding aid 42 contains a conductive material, and the contribution of the conductive material can shield electromagnetic waves and reduce transmission of electromagnetic waves. In addition, since the shielding aid 42 is in contact with the braided body 41, conduction is formed between the conductive material in the shielding aid 42 and the braided body 41, and the current generated when shielding electromagnetic waves is It can escape to ground potential through braid 41 . Therefore, the shielding aid 42 functions as a noise shielding material that assists the noise shielding performance of the braided body 41 and the metal foil 3 . By including the shielding aid 42 in addition to the braided body 41 in the composite shield material 4 in this way, a higher noise shielding effect can be obtained than when only the braided body 41 is used.
 シールド補助剤42が流動性を有しており、編組体41の内部および/または表面、さらに編組体41の周辺の領域に広がりうることにより、シールド材41の各部において、シールド補助剤42が、ノイズ遮蔽性の向上に寄与しうる。特に、シールド補助剤42が、編組体41の金属素線41aの間の空隙Sを充填または被覆することで、シールド補助剤42の寄与によって、空隙Sを介した高周波数の電磁波の透過を効果的に低減することができる。その結果、シールド補助剤42が、高周波域でのノイズ遮蔽性の向上に、高い効果を示す。シールド補助剤42は、流動性を有しており、金属素線41aに挟まれた、あるいは囲まれた領域に、液膜を形成しやすい。その液膜の形成によって、シールド補助剤42が、金属素線41aの間の空隙Sを、隙間なく充填または被覆し、空隙Sを閉塞することで、特にノイズ遮蔽効果が高くなる。 The shielding aid 42 has fluidity and can spread inside and/or on the surface of the braided body 41 and further in the area around the braided body 41. It can contribute to the improvement of noise shielding properties. In particular, the shielding aid 42 fills or covers the gaps S between the metal wires 41a of the braided body 41, and the shielding aid 42 contributes to the transmission of high-frequency electromagnetic waves through the gaps S. can be substantially reduced. As a result, the shield aid 42 exhibits a high effect in improving noise shielding properties in the high frequency range. The shielding aid 42 has fluidity and tends to form a liquid film in the region sandwiched or surrounded by the metal wires 41a. Due to the formation of the liquid film, the shielding aid 42 fills or covers the gaps S between the metal wires 41a without any gaps, and closes the gaps S, thereby particularly enhancing the noise shielding effect.
 さらに、複合シールド材4は、編組体41と流動性を有するシールド補助剤42の複合材として構成されていることにより、高い柔軟性および耐屈曲性を有する。まず、編組体41が、複数の細い金属素線41aが編み込まれて構成されていることにより、高い柔軟性を示す。また、編組体41は、繰り返して屈曲を受けても、金属疲労による損傷を起こしにくい。そして、シールド補助剤42が、流動性を有する物質として構成されていることにより、編組体41の屈曲によく追随して、液膜を形成した状態等を保って、編組体41の内部および/または表面、さらに編組体41の周辺の領域に保持された状態を保つ。編組体41の屈曲運動の途中で、一時的に液膜が途切れること等によって、シールド補助剤42の存在量が少なくなる箇所が生じたとしても、屈曲運動が収束すると、シールド補助剤42がその流動性によって再度広がり、広い領域に行き渡った状態に復帰することができる。よって、複合シールド材4が繰り返して屈曲を受けても、シールド補助剤42によって複合シールド材4のノイズ遮蔽性が高められた状態が、安定に維持される。また、シールド補助剤42が流動性を有する物質として構成され、剛性をほぼ有さないことで、シールド補助剤42が編組体41に保持された複合シールド材4が屈曲を受けても、シールド補助剤42においては、変形による応力の蓄積は実質的に起こらない。よって、シールド材4が屈曲を繰り返し受けても、シールド補助剤42の損傷が生じたり、さらにその損傷が進行したりする事態は生じにくい。 Furthermore, the composite shield material 4 has high flexibility and bending resistance because it is configured as a composite material of the braided body 41 and the fluid shielding aid 42 . First, the braided body 41 exhibits high flexibility because it is constructed by weaving a plurality of thin metal wires 41a. Further, the braided body 41 is less likely to be damaged due to metal fatigue even if it is repeatedly bent. Since the shielding aid 42 is composed of a substance having fluidity, it follows the bending of the braided body 41 well, and maintains the liquid film formed state, etc., and the inside of the braided body 41 and/or or remain held to the surface and also to the area around the braid 41 . Even if the amount of the shielding aid 42 is reduced due to a temporary discontinuity of the liquid film during the bending motion of the braided body 41, the shielding aid 42 will be removed when the bending motion is completed. The liquidity allows it to spread again and return to a state of spreading over a wide area. Therefore, even if the composite shield material 4 is repeatedly bent, the state in which the noise shielding property of the composite shield material 4 is enhanced by the shield auxiliary agent 42 is stably maintained. Further, since the shielding aid 42 is composed of a material having fluidity and has almost no rigidity, even if the composite shielding material 4 held by the braided body 41 is bent, the shielding aid is Substantially no stress buildup due to deformation occurs in agent 42 . Therefore, even if the shielding material 4 is repeatedly bent, damage to the shielding aid 42 is unlikely to occur, and the damage will not progress further.
 このように、複合シールド材4においては、編組体41とシールド補助剤42の両方が高い耐屈曲性を有することで、複合シールド材4全体として高い屈曲性を有し、複合シールド材4、また複合シールド材4が配置された通信用電線1等の通信用部材が繰り返して屈曲を受けても、複合シールド材4の高いノイズ遮蔽性能が安定に維持される。なお、流動性を有するシールド補助剤42の代わりに、導電性材料を含んだ固体物質(ゴム状物質等の弾性体やゲル状物質等、柔軟性を有する固体物質も含め、常温で流動を起こさない物質)を、接合等によって編組体41と複合して編組体41のノイズ遮蔽性能を補助することも考えうる。しかし、この場合には、編組体41の屈曲に伴って、その固体物質に負荷が印加されて内部応力が発生する。屈曲が繰り返されることで、負荷が固体物質に蓄積され、固体物質の破断等の損傷に至る可能性がある。すると、固体物質が付与するノイズ遮蔽性能が、損傷によって低下してしまう。 Thus, in the composite shield material 4, both the braided body 41 and the shielding aid 42 have high flexibility, so that the composite shield material 4 as a whole has high flexibility. Even if the communication member such as the communication wire 1 on which the composite shield material 4 is arranged is repeatedly bent, the high noise shielding performance of the composite shield material 4 is stably maintained. Instead of the shielding aid 42 having flowability, a solid substance containing a conductive material (including an elastic body such as a rubber-like substance and a solid substance having flexibility such as a gel-like substance) can be used. It is also conceivable to combine the braided body 41 and the braided body 41 by bonding or the like to assist the noise shielding performance of the braided body 41 . However, in this case, as the braided body 41 bends, a load is applied to the solid material and internal stress is generated. With repeated flexing, loads build up in solid materials, which can lead to damage, such as fracture of the solid materials. Then, the noise shielding performance imparted by the solid substance is degraded due to the damage.
 上記通信用電線1においては、シールド補助剤42を含んだ複合シールド材4が、金属箔3と積層されて配置されており、複合シールド材4が、屈曲による金属箔3の損傷に伴うノイズ遮蔽性能の低下を補う役割も果たしうる。通信用電線1の屈曲に伴って金属箔3が屈曲を繰り返して受けると、金属疲労により、金属箔3に破断等の損傷が発生する可能性がある。この時に、金属箔3に割れ目が生じると、その割れ目を電磁波が透過することで、金属箔3が有するノイズ遮蔽性が損なわれる可能性がある。特に、コア線2から発生した電磁界を金属箔3の内側に閉じ込めておくことが難しくなる。また、とりわけ高周波域でのノイズ遮蔽性能が低下しやすい。しかし、上記通信用電線1においては、金属箔3の外周に、シールド補助剤42を含み、高い耐屈曲性を備えた複合シールド材4が設けられており、金属箔3に屈曲による損傷が生じたとしても、この複合シールド材4によって、通信用電線1全体として、高いノイズ遮蔽性が維持される。金属箔3に損傷による割れ目が生じたとしても、そのすぐ外側に、流動性を有するシールド補助剤42が編組体41に保持された状態で広がっていることで、割れ目の開口部を編組体41とシールド補助剤42が覆い、それら編組体41およびシールド補助剤42によって、金属箔3の割れ目を介した電磁波の透過が抑制されるからである。 In the above-described communication wire 1, the composite shield material 4 containing the shielding aid 42 is laminated with the metal foil 3, and the composite shield material 4 shields noise accompanying damage to the metal foil 3 due to bending. It can also play a role in compensating for performance degradation. If the metal foil 3 is repeatedly bent as the communication wire 1 is bent, there is a possibility that the metal foil 3 will be damaged, such as broken, due to metal fatigue. At this time, if a crack occurs in the metal foil 3, the noise shielding property of the metal foil 3 may be impaired due to transmission of electromagnetic waves through the crack. In particular, it becomes difficult to confine the electromagnetic field generated from the core wire 2 inside the metal foil 3 . In addition, the noise shielding performance tends to deteriorate especially in a high frequency range. However, in the communication wire 1, the composite shield material 4 containing the shielding aid 42 and having high bending resistance is provided on the outer periphery of the metal foil 3, and the metal foil 3 is damaged by bending. Even so, the composite shielding material 4 maintains the high noise shielding property of the communication wire 1 as a whole. Even if a crack occurs in the metal foil 3 due to damage, the shielding aid 42 having fluidity spreads just outside the crack while being held by the braided body 41, so that the opening of the crack can be formed into the braided body 41. This is because the braided body 41 and the shielding aid 42 suppress transmission of electromagnetic waves through the cracks in the metal foil 3 .
 シールド補助剤42は、流動性を有するものであれば、具体的な粘度は特に限定されない。しかし、編組体41によってシールド補助剤42を安定に保持し、金属素線41aの間の空隙Sを充填または被覆する部位を含め、シールド補助剤42によって連続性の高い液膜を形成させる観点から、シールド補助剤42は、ある程度の粘性を有するものであることが好ましい。具体的には、シールド補助剤42は、粘液状(ペースト状、半液状)であることが好ましい。すると、シールド補助剤42を、金属素線41aの間の空隙Sの箇所を含め、編組体41の内部や表面、また周辺の領域に安定に保持することができ、さらに、複合シールド材4の屈曲を経ても、その安定に保持された状態を維持しやすくなる。例えば、シールド補助剤42の粘度が、5mPa・s以上、さらには10mPa・s以上、100mPa・s以上であることが好ましい。一方、シールド補助剤42の粘度が高すぎても、編組体41の各部に行き渡りにくくなるため、シールド補助剤42の粘度は、1000mPa・s以下、さらには500mPa・s以下であることが好ましい。 The specific viscosity of the shielding aid 42 is not particularly limited as long as it has fluidity. However, from the viewpoint of stably holding the shielding agent 42 by the braided body 41 and forming a highly continuous liquid film with the shielding agent 42 including the portion that fills or covers the gap S between the metal wires 41a. , the shielding aid 42 preferably has a certain degree of viscosity. Specifically, the shielding aid 42 is preferably viscous (paste, semi-liquid). As a result, the shielding aid 42 can be stably held in the interior, surface, and peripheral regions of the braided body 41, including the space S between the metal wires 41a. Even after bending, it becomes easy to maintain the stably held state. For example, the viscosity of the shielding aid 42 is preferably 5 mPa·s or more, more preferably 10 mPa·s or more, or 100 mPa·s or more. On the other hand, if the viscosity of the shielding aid 42 is too high, it will be difficult to spread to each part of the braided body 41, so the viscosity of the shielding aid 42 is preferably 1000 mPa·s or less, more preferably 500 mPa·s or less.
 シールド補助剤42は、導電性物質を含み、流動性を有する材料として構成されていれば、特にその種類や成分組成を限定されるものではない。つまり、例えば液状の導電性ポリマーやイオン液体等、常温で流動性を有する導電性物質よりシールド補助剤42が構成されても、流動性を有する分散媒に対して、導電性物質より構成された粉末材料が分散され、全体として常温で流動性を有する複合材料として、シールド補助剤42が構成されていてもよい。好ましくは、入手の容易性や汎用性等の観点から、分散媒に導電性物質の粉末が分散されている後者の形態の方が好ましい。この場合に、分散媒は、導電性を有していても、非導電性であってもいずれでもよいが、入手の容易性や汎用性等の観点から、非導電性であることが好ましい。特に、非導電性の有機分散媒であることが好ましい。分散媒に分散される導電性物質の粉末は、グラファイトやカーボンブラックをはじめとする炭素材料、導電性酸化物等、非金属導電体の粉末として構成されてもよいが、導電性の高さ等の観点から、金属粉末として構成されることが好ましい。 The type and component composition of the shielding aid 42 are not particularly limited as long as it contains a conductive substance and is configured as a fluid material. In other words, even if the shielding aid 42 is composed of a conductive substance having fluidity at room temperature, such as a liquid conductive polymer or an ionic liquid, the dispersion medium having fluidity does not contain the conductive substance. The shielding aid 42 may be configured as a composite material in which a powder material is dispersed and which is fluid at room temperature as a whole. The latter form, in which the conductive substance powder is dispersed in the dispersion medium, is preferable from the viewpoint of availability, versatility, and the like. In this case, the dispersion medium may be conductive or non-conductive, but is preferably non-conductive from the viewpoint of availability and versatility. In particular, it is preferably a non-conductive organic dispersion medium. The powder of the conductive substance dispersed in the dispersion medium may be composed of a powder of a non-metallic conductor such as a carbon material such as graphite or carbon black, or a conductive oxide. From the point of view, it is preferable to be configured as a metal powder.
 シールド補助剤42を構成する分散媒として好適に用いることができる有機分散媒としては、室温で流動性を有し、かつ揮発性の低い(おおむね沸点にして150℃以上である)有機物であれば、各種の化合物を適用できる。例えば、炭化水素系、エステル系、エーテル系、ケトン系、アルコール系、ハロゲン化炭化水素系等の低揮発性または不揮発性の有機溶剤、液状樹脂や液状ゴム等の液状ポリマー等を好適に用いることができる。また、導電性物質の粉末を分散媒に分散させた際に、粘液状のシールド補助剤42を与えやすいという点で、分散媒が、ある程度の粘度を有していることが好ましい。例えば、分散媒の粘度が、5mPa・s以上、また50mPa・s以下であることが好ましい。適切な粘度を有し、シールド補助剤42を構成する分散媒として好適に用いることができる有機分散媒として、トリメリット酸エステルをはじめとするエステル系有機溶剤、ポリエチレングリコール等を好適に用いることができる。トリメリット酸エステルとしては、トリメリット酸トリス(2-エチルヘキシル)(TOTM)等を挙げることができる。分散媒としては、1種のみを用いても、2種以上の物質を混合して用いてもよい。 As the organic dispersion medium that can be suitably used as the dispersion medium that constitutes the shielding aid 42, any organic substance that has fluidity at room temperature and low volatility (generally boiling point of 150° C. or higher) can be used. , various compounds can be applied. For example, hydrocarbon-based, ester-based, ether-based, ketone-based, alcohol-based, and halogenated hydrocarbon-based low-volatile or non-volatile organic solvents, liquid polymers such as liquid resins and liquid rubbers, etc. can be preferably used. can be done. In addition, the dispersion medium preferably has a certain degree of viscosity in that the viscous shielding aid 42 can be easily applied when the powder of the conductive substance is dispersed in the dispersion medium. For example, the viscosity of the dispersion medium is preferably 5 mPa·s or more and 50 mPa·s or less. As an organic dispersion medium that has an appropriate viscosity and can be suitably used as a dispersion medium that constitutes the shielding aid 42, an ester-based organic solvent such as a trimellitate ester, polyethylene glycol, or the like can be suitably used. can. Examples of the trimellitate include tris(2-ethylhexyl) trimellitate (TOTM). As the dispersion medium, only one substance may be used, or a mixture of two or more substances may be used.
 シールド補助剤42において分散媒に分散される金属粉末を構成する金属種も、特に限定されるものではないが、編組体41や金属箔3のノイズ遮蔽性を効果的に補助する観点から、導電性の高い金属であることが好ましく、非磁性金属であってよい。銅、アルミニウム、銀、金、鉄、コバルト、亜鉛、あるいはそれらの合金を好適に例示することができる。中でも、導電性の高さや汎用性の観点から、銅または銅合金を好適に用いることができる。金属粉末としては、1種のみを用いても、2種以上を混合して用いてもよい。金属粉末の粒径は、特に限定されるものではないが、高いノイズ遮蔽効果を発揮する等の観点から、20μm以上であることが好ましい。一方、複合シールド材4の耐屈曲性を高める等の観点から、100μm以下であることが好ましい。金属粉末の粒子形状も特に限定されるものではなく、球状、扁平形状、不定形等、任意の粒子形状をとることができる。金属粉末は、表面に酸化物等の金属化合物の層を有していてもよく、また、適宜、有機分子等によって表面処理を施されていてもよい。 The metal species constituting the metal powder dispersed in the dispersion medium in the shielding aid 42 is also not particularly limited. It is preferably a metal with high magnetic properties, and may be a non-magnetic metal. Copper, aluminum, silver, gold, iron, cobalt, zinc, or alloys thereof can be preferably exemplified. Among them, copper or a copper alloy can be preferably used from the viewpoint of high conductivity and versatility. As the metal powder, only one type may be used, or two or more types may be mixed and used. Although the particle size of the metal powder is not particularly limited, it is preferably 20 μm or more from the viewpoint of exhibiting a high noise shielding effect. On the other hand, from the viewpoint of enhancing the bending resistance of the composite shield material 4, the thickness is preferably 100 μm or less. The particle shape of the metal powder is not particularly limited, either, and any particle shape such as a spherical shape, a flat shape, and an amorphous shape can be used. The metal powder may have a layer of a metal compound such as an oxide on the surface, and may be surface-treated with an organic molecule or the like as appropriate.
 シールド補助剤42における金属粉末の含有量は、特に限定されるものではないが、十分なノイズ遮蔽性能を発揮させる等の観点からシールド補助剤42全体を100質量%として、80質量%以上であることが好ましい。また、シールド補助剤42全体を100体積%として、38体積%以上であることが好ましい。一方、シールド補助剤42の柔軟性を確保し、耐屈曲性を高める観点、またシールド補助剤42の流動性を確保する観点等から、金属粉末の含有量は、98質量%以下、また85体積%以下に抑えられているとよい。シールド補助剤42において、金属粉末の含有量を増やすほど、シールド補助剤42全体としての導電性が高くなる。しかし、本実施形態にかかるシールド補助剤42においては、分散媒に分散された金属粉末が粒子間で接触し、通信用電線1の軸線方向に沿って、金属粒子によって導電経路が形成されるほどの量で金属粉末が含有されなくても、十分に高いノイズ遮蔽性能を有するシールド補助剤42を構成することができる。シールド補助剤42に含有された金属粉末の少なくとも一部が、編組体41を構成する金属素線41aに接触し、グラウンド電位に接続される編組体41と等電位に保たれるからである。 The content of the metal powder in the shielding aid 42 is not particularly limited, but from the viewpoint of exhibiting sufficient noise shielding performance, etc., it is 80% by mass or more when the entire shielding aid 42 is 100% by mass. is preferred. Moreover, it is preferable that it is 38 volume% or more assuming that the whole shield auxiliary agent 42 is 100 volume%. On the other hand, from the viewpoint of securing the flexibility of the shielding aid 42, enhancing the bending resistance, and securing the fluidity of the shielding aid 42, the content of the metal powder should be 98% by mass or less and 85% by volume. % or less. As the content of the metal powder in the shielding aid 42 increases, the conductivity of the shielding aid 42 as a whole increases. However, in the shielding aid 42 according to the present embodiment, the metal powder dispersed in the dispersion medium contacts between the particles, and along the axial direction of the communication wire 1, the metal particles form a conductive path. Even if the amount of metal powder is not contained, the shielding aid 42 having sufficiently high noise shielding performance can be constructed. This is because at least part of the metal powder contained in the shielding aid 42 is in contact with the metal wires 41a forming the braided body 41, and is kept at the same potential as the braided body 41 connected to the ground potential.
 シールド補助剤42は、流動性や導電性等、シールド補助剤42およびその構成成分が有する特性に著しい影響を与えない限り、適宜、添加剤を含有してもよい。そのような添加剤としては、安定化剤、酸化防止剤、銅害防止剤、滑剤等を例示することができる。 The shielding aid 42 may contain additives as appropriate as long as they do not significantly affect the properties of the shielding aid 42 and its constituent components, such as fluidity and conductivity. Examples of such additives include stabilizers, antioxidants, copper damage inhibitors, lubricants, and the like.
 上でも簡単に述べたように、複合シールド材4を構成する編組体41における編組密度は、特に限定されるものではないが、50%以上であることが好ましい。すると、金属素線41a自体のノイズ遮蔽効果により、また金属素線41aの間の空隙Sを含む部位に、シールド補助剤42を液膜状等で安定に保持できることの効果により、複合シールド材4が高いノイズ遮蔽性能を有するものとなる。一方、編組体41の編組密度は、95%以下であることが好ましい。すると、複合シールド材4を、柔軟化また軽量化することができる。さらに、通信用電線1の軽量化および細径化の観点から、編組密度が80%以下であることが好ましい。95%以下、また80%以下のような編組密度は、一般的に通信用電線1に適用される編組シールドにおける編組密度と比較して低いものであるが、複合シールド材4においては、金属素線41aだけでなくシールド補助剤42もノイズ遮蔽に寄与するため、編組体41の編組密度が低くても、複合シールド材4全体として、十分に高いノイズ遮蔽性能を発揮することができる。また、シールド補助剤42が流動性を有する物質として構成され、表面張力と粘性によって液膜を構成しうるため、編組密度が低く、金属素線41aの間の空隙Sの幅がある程度広い場合でも、液膜の形成によってその空隙Sを閉塞し、空隙Sを介した電磁波の透過を抑制することができる。 As briefly described above, the braid density in the braided body 41 constituting the composite shield material 4 is not particularly limited, but is preferably 50% or more. Then, due to the noise shielding effect of the metal wire 41a itself and the effect that the shielding aid 42 can be stably held in the form of a liquid film or the like in the portion including the gap S between the metal wires 41a, the composite shield material 4 is formed. has high noise shielding performance. On the other hand, the braid density of the braided body 41 is preferably 95% or less. As a result, the composite shield material 4 can be made flexible and lightweight. Furthermore, from the viewpoint of reducing the weight and diameter of the communication wire 1, the braid density is preferably 80% or less. Braid densities of 95% or less and 80% or less are lower than the braid densities of braided shields generally applied to communication wires 1. Since not only the wire 41a but also the shielding aid 42 contributes to noise shielding, even if the braided body 41 has a low braid density, the composite shield material 4 as a whole can exhibit sufficiently high noise shielding performance. In addition, since the shielding aid 42 is composed of a material having fluidity and can form a liquid film by surface tension and viscosity, even if the braid density is low and the width of the gap S between the metal wires 41a is wide to some extent, , the gap S can be closed by forming a liquid film, and transmission of electromagnetic waves through the gap S can be suppressed.
 本実施形態にかかるシールド補助剤42は、金属素線41aを編んで編組体41を形成したうえで、形成された編組体41に、塗布、滴下、浸漬等によってシールド補助剤42を接触させることで、製造することができる。あるいは、編組体41の原料となる金属素線41aの外周に、塗布、滴下、浸漬等によって、シールド補助剤42を液膜等の形で配置しておき、その状態の金属素線41aを編み上げることで、複合シールド材4を製造することができる。この場合にも、シールド補助剤42の流動性により、金属素線41aの外周に配置されたシールド補助剤42を、金属素線41aに占められない領域に相当する空隙Sにも行き渡らせることができる。通信用電線1において、金属箔3で被覆したコア線2の外周に金属素線41aを中空筒状に編み上げて編組体41を形成する場合のように、複合シールド材4を構成する編組体41を連続的に形成する場合には、後者の形態、つまり金属素線41aの外周にシールド補助剤42を配置したうえで金属素線41aを編組構造に編み上げる方法を、好適に採用することができる。特に金属素線41aの外周への、シールド補助剤42の配置を、シールド補助剤42への金属素線41aの浸漬によって行うようにすれば、連続的なシールド材4の形成を簡便に行うことができる。 The shielding aid 42 according to the present embodiment is obtained by knitting the metal wires 41a to form the braided body 41, and then bringing the shielding aid 42 into contact with the formed braided body 41 by coating, dripping, immersion, or the like. and can be manufactured. Alternatively, the shielding aid 42 is placed in the form of a liquid film or the like on the outer circumference of the metal wire 41a, which is the raw material of the braided body 41, by coating, dripping, immersion, or the like, and the metal wire 41a in that state is braided. Thus, the composite shield material 4 can be manufactured. In this case as well, the fluidity of the shielding aid 42 allows the shielding aid 42 arranged around the outer periphery of the metal wire 41a to spread even into the gap S corresponding to the region not occupied by the metal wire 41a. can. The braided body 41 constituting the composite shield material 4 is formed by braiding the metal wires 41a into a hollow tubular shape around the outer circumference of the core wire 2 coated with the metal foil 3 in the communication wire 1. is continuously formed, the latter form, that is, the method of arranging the shielding aid 42 on the outer circumference of the metal wire 41a and then braiding the metal wire 41a into a braided structure can be preferably adopted. . In particular, by immersing the metal wires 41a in the shielding aid 42 to dispose the shielding aid 42 on the outer periphery of the metal wires 41a, the continuous shield material 4 can be easily formed. can be done.
 以下に実施例を示す。ここでは、編組体に対するシールド補助剤の併用の有無による、通信用電線の耐屈曲性への影響を検証した。なお、本発明は以下の実施例によって限定されるものではない。特記しない限り、試料の作製および評価は、室温、大気中にて行った。 An example is shown below. In this study, we examined the influence of the presence or absence of the combined shielding agent on the braided body on the bending resistance of the communication wire. In addition, the present invention is not limited to the following examples. Unless otherwise specified, sample preparation and evaluation were performed at room temperature in air.
<試料の作製>
 試料1として、編組体とシールド補助剤を含む複合シールド材を備えた、同軸型通信用電線を作製した。具体的には、銅合金の撚線として構成された導体の外周にポリプロピレンよりなる絶縁層を形成したコア線を被覆して、金属箔を縦添え状に配置した。金属箔としては、厚さ9μmの銅薄膜と厚さ16μmのPETフィルムを厚さ1μm以下の接着層で接合したものを用いた。
<Preparation of sample>
As a sample 1, a coaxial communication wire was produced, which was equipped with a composite shielding material containing a braid and a shielding aid. Specifically, a core wire having an insulating layer made of polypropylene formed on the outer periphery of a conductor configured as a copper alloy stranded wire was covered, and metal foils were arranged in a vertical manner. As the metal foil, a copper thin film with a thickness of 9 μm and a PET film with a thickness of 16 μm were bonded with an adhesive layer with a thickness of 1 μm or less.
 次に、コア線の外周に配置した金属箔の外側に、複合シールド材を形成した。具体的には、金属素線をシールド補助剤に浸漬しながら、金属箔の外周に中空筒状に編み上げて編組構造を形成することで、編組体とシールド補助剤を含む複合シールド材を形成した。この際、金属素線としては、線径0.1mmのスズめっき軟銅線(TA線)を用い、持数5、打数16、ピッチ16mmの編組構造を形成した。編組密度は58%であった。シールド補助剤としては、0.3~5.0μmの粒径を有する銅粉末を、トリメリット酸エステル(TOTM)に分散させたものを用いた。銅粉末の含有量は、シールド補助剤全体に対して95質量%(68体積%)とした。このシールド補助剤は、粘液状となっていた。上記のようにして作製した複合シールド材においては、金属素線間の空隙にシールド補助剤が充填され、保持されていることが、目視観察によって確認された。さらに、複合シールド材の外周に、シース層を形成することで、試料1の通信用電線を得た。シース層の構成材料としては、オレフィン系熱可塑性エラストマー(TPO)を90質量部、スチレン系熱可塑性エラストマー(SEBS)を10質量部、酸化防止剤を2質量部、難燃剤としての水酸化マグネシウムを120質量部含有するものを用いた。 Next, a composite shield material was formed on the outside of the metal foil placed around the core wire. Specifically, a composite shield material containing the braided body and the shielding aid was formed by forming a braided structure by braiding the metal wires into a hollow cylindrical shape around the outer periphery of the metal foil while immersing the metal wires in the shielding aid. . At this time, a tin-plated annealed copper wire (TA wire) with a wire diameter of 0.1 mm was used as the metal wire, and a braided structure with a number of wires of 5, a number of strokes of 16, and a pitch of 16 mm was formed. The braid density was 58%. Copper powder having a particle size of 0.3 to 5.0 μm dispersed in trimellitate ester (TOTM) was used as the shield aid. The content of the copper powder was 95% by mass (68% by volume) with respect to the entire shielding aid. This shield adjuvant was viscous. In the composite shielding material produced as described above, it was confirmed by visual observation that the gaps between the metal wires were filled with the shielding aid and held therein. Furthermore, a communication wire of sample 1 was obtained by forming a sheath layer on the outer periphery of the composite shield material. The constituent materials of the sheath layer are 90 parts by mass of olefinic thermoplastic elastomer (TPO), 10 parts by mass of styrene thermoplastic elastomer (SEBS), 2 parts by mass of antioxidant, and magnesium hydroxide as a flame retardant. One containing 120 parts by mass was used.
 また、試料2として、シールド補助剤が複合されない通常の編組体をシールド材として備えた、同軸型通信用電線を作製した。ここでは、試料1と同様にして、しかし金属素線をシールド補助剤に浸漬することなく、そのまま編組構造に編み上げて、試料2の通信用電線を得た。 In addition, as sample 2, a coaxial communication wire was produced, which was equipped with a normal braided body, which was not compounded with a shielding aid, as a shielding material. Here, in the same manner as in Sample 1, but without immersing the metal wires in the shielding aid, they were braided into a braided structure to obtain Sample 2 of the communication wire.
<評価方法>
 試料1,2の通信用電線に対して、ノイズ遮蔽性を評価した。評価としては、CISPR25に準拠した放射エミッション評価を行った。具体的には、電波暗室内にて、1500mmに切り出した通信用電線の中央部から側方に1.0m離した位置に、ホーンアンテナを設置した。そして、通信用電線に、1.6GHzの周波数の電気信号を入力し、この際のノイズ放射量を、ホーンアンテナにより計測した。ノイズ放射量が24dB(μV/m)未満の場合をノイズ遮蔽性が高い(A)と評価した。一方、ノイズ放射量が24dB(μV/m)以上の場合をノイズ遮蔽性が低い(B)と評価した。
<Evaluation method>
The noise shielding properties of the communication wires of Samples 1 and 2 were evaluated. As an evaluation, a radiated emission evaluation based on CISPR25 was performed. Specifically, in the anechoic chamber, a horn antenna was installed at a position laterally separated by 1.0 m from the central portion of the communication wire cut to 1500 mm. Then, an electrical signal with a frequency of 1.6 GHz was input to the communication wire, and the amount of noise radiation at this time was measured by a horn antenna. A case where the amount of noise emission was less than 24 dB (μV/m) was evaluated as high noise shielding (A). On the other hand, when the noise radiation amount was 24 dB (μV/m) or more, the noise shielding property was evaluated as low (B).
 試料1,2のそれぞれに対して、初期状態において上記のノイズ遮蔽性の評価を行ったうえで、屈曲試験を実施した。屈曲試験としては、各試料に対して、23℃にて、曲げ半径(R)を50m、屈曲速度を5回/秒、屈曲角度を90°として、1000回の屈曲を行った。その後、上記のノイズ遮蔽性の評価を再度実施した。合わせて、屈曲試験後の試料に対して、目視観察にて、金属箔の状態を確認した。試料1については、複合シールド材の状態も合わせて確認した。 For each of Samples 1 and 2, the above noise shielding performance was evaluated in the initial state, and then a bending test was performed. In the bending test, each sample was bent 1000 times at 23° C. with a bending radius (R) of 50 m, a bending speed of 5 times/second, and a bending angle of 90°. After that, the above noise shielding evaluation was performed again. In addition, the state of the metal foil was confirmed by visual observation of the samples after the bending test. For sample 1, the state of the composite shielding material was also checked.
<評価結果>
 下の表1に、試料1,2について、屈曲試験前後のノイズ遮蔽性の評価結果を示す。
<Evaluation results>
Table 1 below shows the evaluation results of the noise shielding properties of Samples 1 and 2 before and after the bending test.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
 表1に示すように、編組体にシールド補助剤を複合した複合シールド材を用いている試料1および、シールド補助剤を複合していない編組体を用いている試料2の両方とも、屈曲を加えていない初期状態においては、高いノイズ遮蔽性が得られている(A)。しかし、試料2では、屈曲試験を経て、ノイズ遮蔽性が低下しており、ノイズ遮蔽性が低いという結果になっている(B)。これに対し、試料1では、屈曲試験を経ても、高いノイズ遮蔽性が維持されている(A)。 As shown in Table 1, both Sample 1, which uses a composite shield material in which a shielding aid is combined with a braided body, and Sample 2, which uses a braided body that is not combined with a shielding aid, are bent. A high noise shielding property is obtained in the initial state (A). However, in the sample 2, the noise shielding property was degraded through the bending test, and the result was that the noise shielding property was low (B). On the other hand, Sample 1 maintains high noise shielding properties even after the bending test (A).
 屈曲後の試料の目視観察によると、試料2では、金属箔が破断を起こしていた。この破断を介して電磁波が透過することで、屈曲後のノイズ遮蔽性が低くなったものと解釈される。一方、試料1でも、金属箔には破断が生じていたが、複合シールド材に設けられたシールド補助剤が、金属素線間の空隙を含む箇所に、破断のない液膜を形成した状態を維持していた。このことから、金属箔の破断箇所の外側に、編組体とともにシールド補助剤が広がって配置されることで、金属箔の破断箇所を介した電磁波の透過が抑制され、高いノイズ遮蔽性が維持されたものと解釈される。以上の結果から、金属素線にシールド補助剤を接触させた複合シールド材を用いることで、高いシールド遮蔽性が得られるとともに、高い耐屈曲性が得られ、屈曲を経ても高いシールド遮蔽性が維持されることが確認された。 According to visual observation of the sample after bending, in sample 2, the metal foil was broken. It is interpreted that the noise shielding property after bending is lowered because the electromagnetic wave is transmitted through this fracture. On the other hand, even in sample 1, the metal foil was broken, but the shield auxiliary agent provided in the composite shield material formed a liquid film without breakage at the locations including the gaps between the metal wires. had maintained. Therefore, by arranging the shielding aid together with the braid outside the broken portion of the metal foil, transmission of electromagnetic waves through the broken portion of the metal foil is suppressed, and high noise shielding properties are maintained. is interpreted as From the above results, by using a composite shielding material in which a shielding agent is in contact with a metal wire, high shielding performance can be obtained, and high bending resistance can be obtained, and high shielding performance can be obtained even after bending. confirmed to be maintained.
 本発明は上記実施形態に何ら限定されるものではなく、本発明の趣旨を逸脱しない範囲で種々の改変が可能である。 The present invention is by no means limited to the above embodiments, and various modifications are possible without departing from the scope of the present invention.
1     通信用電線
2     コア線
21    導体
22    絶縁層
3     金属箔
4     (複合)シールド材
41    編組体
41a   金属素線
42    シールド補助剤
S     空隙
1 Communication Wire 2 Core Wire 21 Conductor 22 Insulating Layer 3 Metal Foil 4 (Composite) Shield Material 41 Braided Body 41a Metal Wire 42 Shielding Supplement S Void

Claims (10)

  1.  複数の金属素線を編み込んだ編組体と、
     流動性を有し、かつ導電性材料を含み、前記編組体に接触して配置されたシールド補助剤と、を有するシールド材。
    a braided body in which a plurality of metal wires are woven;
    a shielding aid that has fluidity and contains a conductive material and is placed in contact with the braided body.
  2.  前記シールド補助剤は、
     前記編組体を構成する前記複数の金属素線の間の空隙に充填された状態、および
     前記空隙を被覆する状態、の少なくとも一方をとっている、請求項1に記載のシールド材。
    The shielding aid is
    2. The shielding material according to claim 1, wherein at least one of a state in which gaps between said plurality of metal wires constituting said braided body are filled and a state in which said gaps are covered.
  3.  前記シールド補助剤は、粘液状である、請求項1または請求項2に記載のシールド材。 The shielding material according to claim 1 or 2, wherein the shielding aid is viscous.
  4.  前記シールド補助剤は、
     前記導電性材料としての金属粉末と、
     前記金属粉末を分散させる非導電性の分散媒と、を含んでいる、請求項1から請求項3のいずれか1項に記載のシールド材。
    The shielding aid is
    a metal powder as the conductive material;
    4. The shield material according to any one of claims 1 to 3, further comprising a non-conductive dispersion medium for dispersing the metal powder.
  5.  前記シールド補助剤における前記金属粉末の含有量は、80質量%以上、98質量%以下である、請求項1から請求項4のいずれか1項に記載のシールド材。 The shielding material according to any one of claims 1 to 4, wherein the content of the metal powder in the shielding aid is 80% by mass or more and 98% by mass or less.
  6.  前記編組体の編組密度は、50%以上、95%以下である、請求項1から請求項5のいずれか1項に記載のシールド材。 The shield material according to any one of claims 1 to 5, wherein the braid density of the braided body is 50% or more and 95% or less.
  7.  導体と、前記導体の外周を被覆する絶縁層と、を有するコア線と、
     前記コア線の外周を被覆する請求項1から請求項6のいずれか1項に記載のシールド材と、を有する通信用電線。
    a core wire having a conductor and an insulating layer covering the outer periphery of the conductor;
    A communication wire, comprising: the shielding material according to any one of claims 1 to 6, which covers the outer periphery of the core wire.
  8.  前記通信用電線はさらに、前記コア線の外周を被覆する金属箔を有し、
     前記シールド材は、前記金属箔の外周を被覆している、請求項7に記載の通信用電線。
    The communication wire further has a metal foil covering the outer periphery of the core wire,
    8. The electric wire for communication according to claim 7, wherein said shield material covers the outer periphery of said metal foil.
  9.  前記金属箔の厚さは、15μm以下である、請求項8に記載の通信用電線。 The communication wire according to claim 8, wherein the metal foil has a thickness of 15 µm or less.
  10.  前記通信用電線はさらに、前記シールド材の外周を被覆するシース層を有する、請求項7から請求項9のいずれか1項に記載の通信用電線。 The communication wire according to any one of claims 7 to 9, wherein the communication wire further has a sheath layer covering the outer circumference of the shield material.
PCT/JP2022/047014 2021-12-24 2022-12-21 Shielding material, and communication cable WO2023120554A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2021211363A JP2023095457A (en) 2021-12-24 2021-12-24 Shielding material and communication wire
JP2021-211363 2021-12-24

Publications (1)

Publication Number Publication Date
WO2023120554A1 true WO2023120554A1 (en) 2023-06-29

Family

ID=86902575

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2022/047014 WO2023120554A1 (en) 2021-12-24 2022-12-21 Shielding material, and communication cable

Country Status (2)

Country Link
JP (1) JP2023095457A (en)
WO (1) WO2023120554A1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5032757Y1 (en) * 1970-11-13 1975-09-25
JPS61211910A (en) * 1986-02-17 1986-09-20 オムロン株式会社 Cable
JP2003257257A (en) * 2002-03-05 2003-09-12 Hitachi Cable Ltd Coaxial cable and coaxial multi-conductor cable
JP2008293729A (en) * 2007-05-23 2008-12-04 Kurabe Ind Co Ltd Coaxial cable

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5032757Y1 (en) * 1970-11-13 1975-09-25
JPS61211910A (en) * 1986-02-17 1986-09-20 オムロン株式会社 Cable
JP2003257257A (en) * 2002-03-05 2003-09-12 Hitachi Cable Ltd Coaxial cable and coaxial multi-conductor cable
JP2008293729A (en) * 2007-05-23 2008-12-04 Kurabe Ind Co Ltd Coaxial cable

Also Published As

Publication number Publication date
JP2023095457A (en) 2023-07-06

Similar Documents

Publication Publication Date Title
US5262592A (en) Filter line cable featuring conductive fiber shielding
US5262591A (en) Inherently-shielded cable construction with a braided reinforcing and grounding layer
JPH05205536A (en) Shielding material and shielding electric wire-cable product
JPH05140368A (en) Shielding material and shielded electric wire and cable product
US7304246B2 (en) Design for linear broadband low frequency cable
WO2012170279A1 (en) Nested shielded ribbon cables
JP7388527B2 (en) Communication wire
JP7148011B2 (en) Coaxial cable and cable assembly
JP2015153497A (en) Shield cable
KR20180067098A (en) Shield cable using carbon fiber
CN115424771A (en) Cable with shielding structure
JP2013191409A (en) Wire harness and shield structure of wire harness
WO2023120554A1 (en) Shielding material, and communication cable
WO2020241452A1 (en) Electric cable for communication
JP2023040047A (en) Electric wire for communication
JP2012221739A (en) Cable
CN218568461U (en) Cable with shielding structure
JP2022108557A (en) Communication wire
WO2022270281A1 (en) Communication cable
WO2022209960A1 (en) Shield foil and communications electric wire
JP7081699B2 (en) Coaxial cable and cable assembly
KR102195424B1 (en) Protector module for eliminating noise of wiring harness
CN106409424A (en) Carbon-fiber metal composite shielded wire
JP2007087733A (en) Electromagnetic wave shielding cable
JPH11167825A (en) Electric wire/cable and cable cover

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22911256

Country of ref document: EP

Kind code of ref document: A1