Communication cable and manufacturing method of the same

Abstract

To provide a communication cable having high flame retardancy.SOLUTION: A communication cable includes a plurality of conductors and a cable core including an inclusion separating the plurality of conductors from each other, and a resin sheath layer coating the cable core. A ratio of the mass of the sheath layer to the total mass of the components of the plurality of conductors and the communication cable other than the sheath layer is more than 87% and 300% or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a communication cable and a method for manufacturing the same. [Background technology]

[0002] In recent years, communication cables such as LAN (Local Area Network) cables have been used to connect various devices, such as between servers, between servers and switches, and between servers and personal computers, and are required to be suitable for high-speed data communication.

[0003] Patent Document 1 describes a twisted pair cable for LAN that has a plurality of twisted pairs, a flame-retardant layer that covers the twisted pairs, and an outer sheath that covers the flame-retardant layer. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-21928 Summary of the Invention [Problem to be solved by the invention]

[0005] To make the LAN twisted pair cable described in Patent Document 1 compatible with standards of Category 6 or higher, it is necessary to provide an interposer to separate the twisted pairs. However, when the LAN twisted pair cable described in Patent Document 1 is made compatible with standards of Category 6 or higher, the amount of flammable material in the LAN twisted pair cable increases, leaving room for further consideration of flame retardancy.

[0006] SUMMARY OF THE INVENTION It is therefore a primary object of the present invention to provide a communication cable having higher flame retardancy and a method for manufacturing the same. [Means for solving the problem]

[0007] In order to solve the above problem, according to one aspect of the present invention, a cable core including a plurality of conductors and intervening spaces separating the plurality of conductors from one another; an outer jacket layer covering the cable core; A communication cable having The ratio of the mass of the outer jacket layer to the total mass of components of the communication cable other than the plurality of conductors and the outer jacket layer is more than 87% and 300% or less. A communications cable is provided.

[0008] In order to solve the above problem, according to another aspect of the present invention, A method for manufacturing a communication cable, comprising: providing a cable core including a plurality of conductors and intervening spaces separating the plurality of conductors from one another; covering the cable core with a first jacket layer; forming an intermediate layer, which is a release layer or a flame-retardant tape layer, on the first outer layer; covering the intermediate layer with a second jacket layer; and a ratio of a total mass of the first outer covering layer, the intermediate layer, and the second outer covering layer to a total mass of components of the communication cable other than the plurality of conductors, the first outer covering layer, the intermediate layer, and the second outer covering layer is more than 87% and 300% or less; A method for manufacturing a communications cable is provided. [Effects of the Invention]

[0009] According to the present invention, a communication cable having high flame retardancy and a method for manufacturing the same can be provided. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view of a communication cable according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a flowchart of the method for manufacturing the communication cable according to the first embodiment of the present invention. [Figure 3]FIG. 3 is a cross-sectional view of a communication cable according to a second embodiment of the present invention. [Figure 4] FIG. 4 is a flowchart of a method for manufacturing a communication cable according to the second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] The following describes communication cables and manufacturing methods thereof according to embodiments of the present invention. However, the communication cables and manufacturing methods thereof according to the present invention are not limited to the embodiments described below. In this specification, the symbol "to" indicating a range of values ​​means that the upper and lower limits of the range are included.

[0012] [Embodiment 1] (Communication cable configuration) FIG. 1 is a cross-sectional view of a communication cable 10 according to a first embodiment of the present invention.

[0013] The communication cable 10 is a so-called LAN cable, and has a cable core 20 including a plurality of twisted pairs 21 and fillers 22, and an outer sheath layer 50. In addition to the above configuration, the communication cable 10 may have a winding layer 30 and a shielding layer 40. As shown in FIG. 1 , in this embodiment, the communication cable 10 has the cable core 20, the winding layer 30, the shielding layer 40, and the outer sheath layer 50.

[0014] The cable core 20 includes a plurality of twisted pairs 21 and interposers 22 that separate the plurality of twisted pairs 21 from one another. The twisted pairs 21 include a plurality of insulated wires 23. In this embodiment, the twisted pairs 21 include two insulated wires 23. In the twisted pairs 21, the two insulated wires 23 are twisted together to form a predetermined twist pitch. Here, the twist pitch refers to the lengthwise distance of the twisted pairs 21 required for one insulated wire 23 to make one turn when the two insulated wires 23 are twisted together. The number of twisted pairs 21 is not particularly limited as long as it is plural. In this embodiment, the number of twisted pairs 21 is four.

[0015] The insulated wire 23 has a conductor 24 and an insulating layer 25 that covers the conductor 24 .

[0016] The conductor 24 is a conducting wire made of a conductive metal material. The type of conductor 24 is not particularly limited as long as it is made of a conductive metal material. In this embodiment, the conductor 24 is a soft copper wire. The conductor 24 may be a solid wire or a twisted wire made by twisting together a plurality of wires. The thickness of the conductor 24 (the diameter of the cross section perpendicular to the length direction) is not particularly limited. The thickness of the conductor 24 is selected appropriately depending on the use and type of the communication cable 10. The diameter of the conductor 24 is, for example, within a range of 0.3 to 0.6 mm.

[0017] The insulating layer 25 covers the conductor 24. The material of the insulating layer 25 is not particularly limited as long as it has insulating properties. In this embodiment, the insulating layer 25 is made of polyethylene. The thickness of the insulating layer 25 is not particularly limited and can be selected appropriately. The thickness of the insulating layer 25 is, for example, within the range of 0.1 to 0.3 mm.

[0018] The insert 22 separates the multiple twisted pairs 21 from one another. The insert 22 extends in the longitudinal direction of the communication cable 10. The shape of the insert 22 is not particularly limited as long as it can separate the multiple twisted pairs 21 from one another. In this embodiment, the cross-sectional shape of the insert 22 perpendicular to the extension direction is a plus sign shape. That is, in this embodiment, the insert 22 is a cross insert. Furthermore, the material of the insert 22 is not particularly limited as long as it can perform the above-mentioned function. In this embodiment, the material of the insert 22 is polyethylene. The insert 22 is twisted along the longitudinal direction of the communication cable 10 together with the multiple twisted pairs 21.

[0019] The winding layer 30 covers the cable core 20 on the inner side of the outer sheath layer 50. The winding layer 30 maintains a constant distance between the cable core 20 and the shielding layer 40. Examples of materials for the winding layer 30 include resin or glass. Examples of materials for the winding layer 30 include nonwoven fabric tapes made of one or more of polyester, polypropylene, aramid fiber, nylon, acrylic fiber, and glass fiber. In this embodiment, the material for the winding layer 30 is polyester nonwoven fabric tape. The winding layer 30 is wound horizontally from above the cable core 20. There are no particular restrictions on the number of winding layers 30 as long as the purpose and effect of this embodiment are not impaired. The basis weight of the tape constituting the winding layer 30 is 90 to 110 g / m 2 and preferably 95 to 105 g / m 2 The thickness of the winding layer 30 is not particularly limited as long as it can perform the above functions, and can be selected appropriately. The thickness of the winding layer 30 is, for example, within the range of 0.1 to 0.5 mm.

[0020] The shielding layer 40 covers the winding layer 30 on the inner side of the outer covering layer 50. The shielding layer 40 is made of a metal laminate tape. The metal laminate tape (metal tape) includes a resin sheet and a metal foil discontinuously laminated on the resin sheet. That is, the metal foil has slits for blocking electrical continuity. An example of a metal laminate tape is an Al / PET tape in which an aluminum (Al) foil is laminated on a polyethylene terephthalate (PET) film. In this embodiment, the metal laminate tape of the shielding layer 40 is an Al / PET tape. The resin sheet includes a resin film. The thickness of the resin sheet (resin film) is not particularly limited and can be set as appropriate. The shielding layer 40 is wound horizontally over the winding layer 30. The thickness of the shielding layer 40 is not particularly limited and can be selected as appropriate as long as it can perform the above-mentioned functions. The thickness of the shielding layer 40 is, for example, within the range of 0.01 to 0.1 mm.

[0021] The outer sheath layer 50 is made of resin and covers the shielding layer 40. The outer sheath layer 50 protects the cable core 20. The outer sheath layer 50 may be a single layer or multiple layers. In this embodiment, the outer sheath layer 50 has a single-layer structure. The material of the outer sheath layer 50 is a resin, and is not particularly limited as long as it can perform the above-mentioned functions. Examples of materials for the outer sheath layer 50 include polyvinyl chloride and polyolefin. In this embodiment, the material of the outer sheath layer 50 is flame-retardant polyethylene. The thickness of the outer sheath layer 50 is not particularly limited. The thickness of the outer sheath layer 50 is, for example, in the range of 0.3 to 1.5 mm, and more preferably in the range of 0.5 to 0.9 mm.

[0022] The outer coating layer 50 generally contains a flame retardant. The inclusion of a flame retardant further improves the flame retardancy. Examples of flame retardants include red phosphorus and aluminum hydroxide. Red phosphorus is preferred as the flame retardant. The amount of the flame retardant in the outer coating layer 50 is not particularly limited as long as it can exhibit the above-mentioned functions and may be set appropriately.

[0023] In the communication cable 10 according to the present embodiment, the mass ratio of the outer jacket layer 50 to the total mass of the components of the communication cable 10 other than the multiple conductors 24 and the outer jacket layer 50 is greater than 87% and less than or equal to 300%. If this ratio is less than 87%, the required flame retardancy may not be achieved. In other words, in this embodiment, the insulating layer 25, the filler 22, the winding layer 30, and the shielding layer 40 are combustible, and if the proportion of their total mass is too high, flame retardancy cannot be achieved. If this ratio exceeds 300%, the outer jacket layer 50 becomes too thick, reducing the processability of the communication cable 10. In this embodiment, the total mass of the components of the communication cable 10 other than the multiple conductors 24 and the outer jacket layer 50 refers to the total mass of the insulating layer 25, the filler 22, the winding layer 30, and the shielding layer 40. For example, the total mass of the components other than the conductors 24 and the outer sheath layer 50 is within a range of 5 to 30 kg / km, and the mass of the outer sheath layer 50 is within a range of 5 to 90 kg / km. This ratio is preferably 100% or more, and more preferably 125% or more. Furthermore, this ratio is preferably 250% or less, and more preferably 200% or less.

[0024] (Communication cable manufacturing method) FIG. 2 is a flowchart of a method for manufacturing the communication cable 10 according to the first embodiment.

[0025] The communication cable 10 can be manufactured, for example, by the following method. Here, a communication cable 10 having a cable core 20, a winding layer 30, a shielding layer 40, and an outer jacket layer 50 will be described.

[0026] The manufacturing method of the communication cable 10 includes a step of preparing the cable core 20 (S110), a step of forming the winding layer 30 (S120), a step of forming the shielding layer 40 (S130), and a step of forming the outer sheath layer 50 (S140).

[0027] In the step (S110) of preparing cable core 20, polyethylene is extruded from the die of an extruder while conveying conductor 24 in the longitudinal direction, and conductor 24 is covered with insulating layer 25 to form insulated wire 23. Next, a plurality of insulated wires 23 (two in this case) are gathered together and twisted in a predetermined direction a predetermined number of times to form twisted pair wire 21. Next, interposer 22 is arranged so that the twisted pair wires 21 do not come into contact with each other.

[0028] In the step (S120) of forming the winding layer 30, the winding layer 30 is formed on the cable core 20. Specifically, in this embodiment, the winding layer 30 is formed by winding a polyester nonwoven fabric tape laterally.

[0029] In the step (S130) of forming the shielding layer 40, the shielding layer 40 is formed on the winding layer 30. Specifically, in this embodiment, the shielding layer 40 is formed by winding an Al / PET tape laterally.

[0030] In the step (S140) of forming the outer jacket layer 50, the outer jacket layer 50 is formed on the cable core 20 on which the winding layer 30 and the shielding layer 40 have been formed. Specifically, in this embodiment, flame-retardant polyethylene is extruded from the die of an extruder, and the shielding layer 40 is covered with the outer jacket layer 50 to obtain the communication cable 10. At this time, the mass of the outer jacket layer 50 is adjusted so that the ratio of the mass of the outer jacket layer 50 to the total mass of the components of the communication cable 10 other than the multiple conductors 24 and the outer jacket layer 50 (the insulating layer 25, the filler 22, the winding layer 30, and the shielding layer 40) is more than 87% and not more than 300%.

[0031] (effect) As described above, according to the present invention, the ratio of the mass of the outer jacket layer 50 to the total mass of the components other than the multiple conductors 24 and the outer jacket layer 50 is more than 87% and not more than 300%, thereby improving flame retardancy.

[0032] [Embodiment 2] Next, a description will be given of a communication cable 60 according to a second embodiment. The communication cable 60 according to the second embodiment differs from the communication cable 10 according to the first embodiment in the configuration of the outer sheath layer 70.

[0033] (Communication cable configuration) FIG. 3 is a cross-sectional view of a communication cable 60 according to the second embodiment.

[0034] The communication cable 60 is a so-called LAN cable, and has a cable core 20 including a plurality of twisted pairs 21 and fillers 22, and an outer sheath layer 70. In addition to the above configuration, the communication cable 60 may also have a winding layer 30 and a shielding layer 40. As shown in FIG. 3 , in this embodiment, the communication cable 60 has a cable core 20 including a plurality of twisted pairs 21 and fillers 22, the winding layer 30, the shielding layer 40, and the outer sheath layer 70. The cable core 20, the winding layer 30, and the shielding layer 40 are the same as the respective components in the first embodiment, and therefore description thereof will be omitted.

[0035] The outer covering layer 70 of this embodiment has a first outer covering layer 71 , an intermediate layer 72 , and a second outer covering layer 73 .

[0036] The first outer jacket layer 71 covers the shielding layer 40. The first outer jacket layer 71 protects the multiple twisted pairs 21 and the filler 22. The material of the first outer jacket layer 71 is not particularly limited as long as it can perform the above-mentioned functions. Examples of materials for the first outer jacket layer 71 include polyvinyl chloride and polyolefin. In this embodiment, the material of the first outer jacket layer 71 is flame-retardant polyethylene. The thickness of the first outer jacket layer 71 is not particularly limited. The thickness of the first outer jacket layer 71 is, for example, within a range of 0.3 to 0.7 mm, and more preferably within a range of 0.3 to 0.5 mm. The outer diameter of the first outer jacket layer 71 is within a range of 4.0 to 8.0 mm. If the outer diameter of the first outer jacket layer 71 is within the above range, the communication cable 60 excluding the intermediate layer 72 and the second outer jacket layer 73 can be properly connected to, for example, an RJ45 connector.

[0037] The intermediate layer 72 covers the first outer layer 71. The intermediate layer 72 facilitates peeling of the second outer layer 73 from the first outer layer 71. Examples of the intermediate layer 72 include a release layer made of silicone and a flame-retardant tape layer made of a flame-retardant tape such as a nonwoven fabric containing ammonium polyphosphate. In this embodiment, the intermediate layer 72 is a release layer made of silicone. The thickness of the intermediate layer 72 is not particularly limited. The thickness of the release layer made of silicone is, for example, within a range of 1 to 100 μm. The thickness of the flame-retardant tape is, for example, within a range of 0.05 to 0.3 mm, approximately 0.2 mm. The presence of the intermediate layer 72 allows, for example, scissors or the like to be inserted between the shielding layer 40 and the first outer layer 71, making it easy to remove the intermediate layer 72 and the second outer layer 73.

[0038] The second outer layer 73 covers the intermediate layer 72. The material of the second outer layer 73 is not particularly limited as long as it can perform the above-mentioned functions. Examples of materials for the second outer layer 73 include polyvinyl chloride and polyolefin. The material of the second outer layer 73 may be the same as or different from the material of the first outer layer 71. In this embodiment, the material of the second outer layer 73 is the same as the material of the first outer layer 71. That is, in this embodiment, the material of the second outer layer 73 is flame-retardant polyethylene. The thickness of the second outer layer 73 is not particularly limited. The thickness of the second outer layer 73 is, for example, in the range of 0.3 to 1.2 mm, and more preferably in the range of 0.3 to 0.8 mm.

[0039] The ratio of the mass of the outer jacket layer 70 to the total mass of the components of the communication cable 60 other than the conductors 24 and the jacket layer 70 is more than 87% and less than or equal to 300%. If this ratio is less than 87%, the flame retardant effect cannot be obtained. If this ratio is more than 300%, the jacket layer 70 becomes thick, resulting in reduced processability. In this embodiment, the total mass of the components of the communication cable 60 other than the conductors 24 and the jacket layer 70 refers to the total mass of the insulating layer 25, the filler 22, the winding layer 30, and the shielding layer 40. For example, the total mass of the components of the communication cable 60 other than the conductors 24 and the jacket layer 70 is within a range of 5 to 30 kg / km, and the mass of the jacket layer 70 is within a range of 10 to 90 kg / km. The ratio is preferably more than 100%, more preferably more than 125%. The ratio X is preferably less than or equal to 250%, more preferably less than or equal to 200%.

[0040] (Communication cable manufacturing method) FIG. 4 is a flowchart of another method for manufacturing the communication cable 60 according to the second embodiment.

[0041] The communication cable 60 can be manufactured, for example, by the following method. Here, a communication cable 60 having a cable core 20, a winding layer 30, a shielding layer 40, and an outer jacket layer 70 will be described.

[0042] The manufacturing method of the communication cable 60 includes a step of preparing the cable core 20 (S110), a step of forming the winding layer 30 (S120), a step of forming the shielding layer 40 (S130), a step of forming the first outer sheath layer 71 (S240), a step of forming the intermediate layer 72 (S250), and a step of forming the second outer sheath layer 73 (S260).

[0043] In the step (S110) of preparing cable core 20, polyethylene is extruded from the die of an extruder while conveying conductor 24 in the longitudinal direction, and conductor 24 is covered with insulating layer 25 to form insulated wire 23. Next, a plurality of insulated wires 23 (two in this case) are gathered together and twisted in a predetermined direction a predetermined number of times to form twisted pair wire 21. Next, interposer 22 is arranged so that the twisted pair wires 21 do not come into contact with each other.

[0044] In the step (S120) of forming the winding layer 30, the winding layer 30 is formed on the cable core 20. Specifically, in this embodiment, the winding layer 30 is formed by winding a polyester nonwoven fabric tape laterally.

[0045] In the step (S130) of forming the shielding layer 40, the shielding layer 40 is formed on the winding layer 30. Specifically, in this embodiment, the shielding layer 40 is formed by winding an Al / PET tape laterally.

[0046] In the step (S240) of forming the first outer jacket layer 71, the first outer jacket layer 71 is formed on the cable core 20 on which the winding layer 30 and the shielding layer 40 have been formed. Specifically, in this embodiment, flame-retardant polyethylene is extruded from the die of an extruder to coat the shielding layer 40 with the flame-retardant polyethylene, thereby forming the first outer jacket layer 71.

[0047] In the step (S250) of forming the intermediate layer 72, the intermediate layer 72 is formed on the first outer layer 71. Specifically, in this embodiment, the intermediate layer 72 is formed by applying an intermediate paint onto the first outer layer 71 and drying it. Alternatively, the intermediate layer 72 may be formed by wrapping a flame-retardant tape horizontally.

[0048] In the step (S260) of forming the second outer jacket layer 73, the second outer jacket layer 73 is formed on the cable core 20 on which the first outer jacket layer 71 and the intermediate layer 72 have been formed. Specifically, in this embodiment, the communication cable 60 is obtained by extruding flame-retardant polyethylene from the die of an extruder, coating the intermediate layer 72 with the flame-retardant polyethylene, and forming the second outer jacket layer 73.

[0049] (effect) As described above, according to the present invention, the outer sheath layer 70 has the first outer sheath layer 71 and the second outer sheath layer 73. Therefore, the first outer sheath layer 71 is exposed by peeling off the second outer sheath layer 73. Therefore, compared to the communication cable 10 of the first embodiment, the communication cable having the first outer sheath layer 71 can be more easily connected to a connector, and processability can be improved. [Example]

[0050] The present invention will be described in more detail below with reference to examples. However, the scope of the present invention is not limited by these examples, and the embodiments can be modified without departing from the spirit of the present invention.

[0051] 1. Making a communication cable (1) Preparation of communication cable 1 An insulated wire with an insulating layer was formed by extrusion coating polyethylene around a annealed copper wire (conductor). Two insulated wires were then twisted together (twisted) to form a twisted pair wire. Four twisted pairs were then placed around a polyethylene cross insert, and a 0.3 mm thick polyester nonwoven tape was wrapped around it in a 1 / 2 overlap as a winding layer (the nonwoven tape was wound with an overlap of 1 / 2 the width). A 0.05 mm thick Al / PET tape was then wrapped around it in a 1 / 4 overlap to form a shielding layer. Flame-retardant polyethylene was then extrusion coated around the shielding layer, producing a communication cable with an outer jacket layer with an outer diameter of 7.0 mm. The ratio of the total mass of the jacket layer to the total mass of the insulation layer, cross insert, winding layer, and shielding layer, which are components of the communication cable other than the conductor and jacket layer, was 100%.

[0052] (2) Preparation of communication cable 2 An insulated wire with an insulating layer was formed by extrusion coating polyethylene around a annealed copper wire (conductor). Two insulated wires were then twisted together (twisted) to form a twisted pair wire. Four twisted pairs were then arranged around a polyethylene cross insert, and a 0.3 mm thick polyester nonwoven tape was wound in a 1 / 2 overlap winding pattern (the nonwoven tape was wound with an overlap of 1 / 2 the width). A 0.05 mm thick Al / PET tape was then wound in a 1 / 4 overlap winding pattern to form a shielding layer. Flame-retardant polyethylene was then extrusion coated around the shielding layer to form a first outer jacket layer with an outer diameter of 8.0 mm. A 0.1 mm thick flame-retardant tape was then wound in a 1 / 2 overlap winding pattern around the first outer jacket layer to form an intermediate layer. Flame-retardant polyethylene was then extrusion coated around the intermediate layer to produce a communication cable with a second outer jacket layer with an outer diameter of 9.0 mm. The ratio of the total mass of the first outer sheath layer, intermediate layer and second outer sheath layer to the total mass of the insulating layer, cross-insertion layer, winding layer and shielding layer, which are components of the communication cable other than the conductor, first outer sheath layer, intermediate layer and second outer sheath layer, was 125%.

[0053] (3) Fabrication of communication cable 3 Communication cable 3 was produced in the same manner as communication cable 2, except that the outer diameter of the first outer sheath layer was 8.0 mm, the outer diameter of the second outer sheath layer was 9.0 mm, and a silicone resin was applied to the first outer sheath layer and dried as an intermediate layer. The ratio of the total mass of the first outer sheath layer, intermediate layer, and second outer sheath layer to the total mass of the insulating layer, cross-insertion layer, winding layer, and shielding layer (other than the conductor, first outer sheath layer, intermediate layer, and second outer sheath layer) was 175%.

[0054] (4) Preparation of communication cable 4 Communication cable 4 was obtained in the same manner as communication cable 2, except that the outer diameter of the first outer sheath layer was 8.0 mm, the outer diameter of the second outer sheath layer was 11.0 mm, and the ratio of the total mass of the first outer sheath layer, intermediate layer and second outer sheath layer to the total mass of the insulating layer, cross-insertion layer, winding layer and shielding layer, which are components of the communication cable other than the conductor, first outer sheath layer, intermediate layer and second outer sheath layer, was 300%.

[0055] (5) Manufacturing of communication cable 5 Communication cable 5 was obtained in the same manner as communication cable 1, except that the ratio of the total mass of the outer sheath layer to the total mass of the insulating layer, cross-insertion layer, winding layer, and shielding layer, which are components of the communication cable other than the conductor and outer sheath layer, was 350%.

[0056] (6) Manufacturing of communication cable 6 Communication cable 6 was obtained in the same manner as communication cable 1, except that the outer diameter of the outer sheath layer was 7.5 mm and the ratio of the total mass of the outer sheath layer to the total mass of the insulating layer, cross-insertion layer, winding layer and shielding layer, which are components of the communication cable other than the conductor and outer sheath layer, was 87%.

[0057] 2. Evaluation (1) Flammability 1 The flammability of each of the manufactured communication cables was examined in accordance with IEEE383-1974 (vertical tray combustion test). Flammability 1 was evaluated according to the following criteria. ○: The fire did not spread to the top of the cable during the 20-minute burning time. ×: The fire spread to the top of the cable within 20 minutes of burning.

[0058] (2) Flammability 2 The flammability of each manufactured communication cable was examined in accordance with UL1581-1080 (VW-1 vertical flame test). Flammability 2 was evaluated according to the following criteria. ○: Meets UL1581-1080 standards. ×: Did not meet the UL1581-1080 standards.

[0059] (3) Electrical characteristics The performance of Category 6A (Cat. 6A) of ANSI / TIA-568.2-D-2018 "Balanced Twisted-Pair Telecommunications Cabling and Components Standards" was evaluated based on the following criteria. ○: Met the standard values ​​for LAN twisted pair cables. ×: The standard value for LAN twisted pair cables was not met.

[0060] (4) Processability The outer sheath was stripped off from the end of the sample cable in the usual way, and the cable was connected to a general-purpose connector for unshielded twisted pair cable. The workability was evaluated according to the following criteria. ◎: It was easier to connect to the connector. ○: The connector was connected. △: It can be connected to the connector, but it is difficult to insert into the connector. ×: The outer layer is difficult to remove.

[0061] Table 1 shows the parameters of each communication cable manufactured and the evaluation results.

[0062] [Table 1]

[0063] As shown in Table 1, communication cables 1 to 4, in which the mass ratio of the outer jacket layer to the total mass of the components of the communication cable other than the conductor and the outer jacket layer was greater than 87% and less than 300%, exhibited good flame retardancy and flammability. In particular, communication cable 2, which had a first outer jacket layer, an intermediate layer made of flame-retardant tape, and a second outer jacket layer, exhibited better processability. This is thought to be because the inclusion of flame-retardant tape as a material for the intermediate layer increased flame retardancy and made the second outer jacket layer more susceptible to peeling. On the other hand, communication cable 5, in which the mass ratio of the outer jacket layer to the total mass of the components of the communication cable other than the conductor and the outer jacket layer was greater than 300%, exhibited poor processability. Furthermore, communication cable 6, in which the mass ratio of the outer jacket layer to the total mass of the components of the communication cable other than the conductor and the outer jacket layer was less than 87%, exhibited poor flammability 1 and flammability 2. [Industrial Applicability]

[0064] The communication cable according to the present invention is useful as a LAN cable capable of high-speed communication. [Explanation of symbols]

[0065] 10, 60 communication cable 20 cable cores 21 twisted pair wire 22 Intervention 23 Insulated wire 24 conductors 25 insulating layer 30 Rolled layer 40 Shielding layer 50, 70 outer covering layer 71 First outer layer 72 Middle Class 73 Second outer layer

Claims

1. a cable core including a plurality of conductors and intervening spaces separating the plurality of conductors from one another; an outer jacket layer covering the cable core; A communication cable having a ratio of the mass of the outer jacket layer to the total mass of components of the communication cable other than the plurality of conductors and the outer jacket layer is more than 87% and not more than 300%; Communication cable.

2. 2. The communication cable of claim 1, a winding layer that covers the cable core on the inner side of the outer sheath layer; a shielding layer including a resin sheet and a metal tape discontinuously laminated on the resin sheet, the shielding layer covering the winding layer on the inner side of the outer covering layer; further comprising Communication cable.

3. 2. The communication cable of claim 1, The outer covering layer is a first jacket layer covering the cable core; a second outer jacket layer covering the first outer jacket layer; having Communication cable.

4. 4. The communication cable of claim 3, The outer covering layer further includes an intermediate layer which is a release layer or a flame-retardant tape layer disposed between the first outer covering layer and the second outer covering layer. Communication cable.

5. 4. The communication cable of claim 3, The thickness of the first outer coating layer is within a range of 0.3 to 0.5 mm. Communication cable.

6. A method for manufacturing a communication cable, comprising: providing a cable core including a plurality of conductors and intervening spaces separating the plurality of conductors from one another; covering the cable core with a first jacket layer; forming an intermediate layer, which is a release layer or a flame-retardant tape layer, on the first outer layer; covering the intermediate layer with a second jacket layer; and a ratio of a total mass of the first outer covering layer, the intermediate layer, and the second outer covering layer to a total mass of components of the communication cable other than the plurality of conductors, the first outer covering layer, the intermediate layer, and the second outer covering layer is more than 87% and 300% or less; A method for manufacturing communication cables.

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