JP2006221889A - Manufacturing method of thermoplastic resin spiral body, and thermoplastic resin spiral body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a thermoplastic resin spiral body in which improvement of a manufacturing speed is achieved without using a rotary dice. <P>SOLUTION: The manufacturing method shown in the figure is constituted of a first process and a second process in a continued state. In the first process, a plastically deformable conductive inner conductor (core material) 12 is penetrated through a cross head dice of a melt extruder 20, a molten thermoplastic resin is drawn out while being cooled with a cooling device 22 of which the temperature is less than a melting point after it is extrusion-molded to the outer periphery of the inner conductor 12 by the dice of a prescribed shape, and a molded product 26 having a linear pillar part 24 for linearly extending in the longitudinal direction is formed. In the second process, a tension roller 30, a rotary receiving machine 32, and a rotary winding machine 34 are provided, and by adding twisting because of rotation around the major axis by the rotary receiving machine 32 while adding tension to the molded product 26 by the tension roller, and by deforming the linear pillar part 24 into a spiral pillar part 14b, the thermoplastic resin spiral body 10 is obtained. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a method for producing a thermoplastic resin spiral and a thermoplastic resin spiral, and is particularly useful as a communication cable such as a coaxial cable core and an optical cable carrier (spacer), and a member of a communication wire. The present invention relates to a method for producing a thermoplastic resin spiral and a thermoplastic resin spiral.

  The core of a coaxial cable having a hollow structure having an inner conductor (core material) at the center and spirally coated with a thermoplastic resin such as high-density polyethylene (HDPE) around the core is disclosed in, for example, Patent Document 1 Is disclosed. In the manufacturing method of the core body shown in Patent Document 1, a molten material is extruded around a inner conductor (core material) by a rotating (unshaped) die to form a spiral.

The core of the coaxial cable having such a configuration has an advantage that a dielectric constant (hollow ratio = the ratio of air can be increased) difficult to obtain by foam molding can be obtained. However, such a conventional manufacturing method has the following drawbacks.
JP 2004-55144 A

That is, in the core manufacturing method using a rotating die,
A. For example, depending on the shape, such as when the rib is elongated (the hollow ratio is high), the rib is inclined and the desired shape accuracy cannot be obtained.

B. In the case of a spiral object with a small outer diameter, if the spiral pitch is shortened and an attempt is made to increase the production speed, the rotational speed of the rotary die will be increased. For this reason, the manufacturing speed is slowed and the cost is increased.

C. If the inner conductor (core material) is thin or soft, the covered portion also rotates and the helical pitch is disturbed by the rotation of the resin.

D. Fluorine resin (PFA, FEP), PPS, PPO (polyphenylene oxide), PSF (polysulfone), PES (polyethersulfone), PEI (polyetherimide), PEN (polyethylene naphthalate), LCP (aromatic polyester), etc. In the case of a heat-resistant resin having a melt extrusion temperature of around 300 ° C. or higher, a lubrication seal structure with high heat resistance of the rotary bearing cannot be formed. However, a fluorine resin having a low dielectric constant is preferable, but a fluorine resin spiral material having an internal conductor could not be actually produced.

E. In addition, in the case of a resin having a low viscosity such as PET or PBT, the spiral portion is easily deformed by rotation, and a spiral object with good shape accuracy cannot be obtained.

  Further, a hollow core in which a copper wire is used for an inner conductor (core material) and a fluorine resin is spirally insulated and coated is useful as a core of a hollow structure coaxial cable. Compared with the foaming method, the hollowness is increased (air volume of 50% or more), and the dielectric constant can be reduced.

  However, in order to obtain good reflection characteristics, high accuracy is required for the helical shape, the helical pitch, etc., but there has been no effective method for producing a high-precision fluorine resin helical material.

  Furthermore, polyolefins, especially HDPE, used as the coating resin are useful as optical cable spacers in addition to the hollow core for coaxial cables. However, if the helical pitch is shortened, the rotational speed of the rotary die is increased. Problems occur.

  The present invention has been made in view of such conventional problems, and the object of the present invention is to produce a spiral object without using a rotating die, resulting from the rotating die described above. It is an object of the present invention to provide a method for producing a thermoplastic resin spiral product and a thermoplastic resin spiral product that can solve the problems A to E and obtain a spiral product having high shape accuracy and pitch accuracy.

  In addition, the spiral material by fluorine resin coating and polyethylene coating is useful as a core of a coaxial cable or a wire member for communication, and the spiral material such as HDPE is useful as a spacer for optical cable (member for optical cable). is there.

  In order to achieve the above object, a plastically deformable conductive inner conductor or core material such as an annealed copper wire, a hard copper wire, or a copper-clad steel wire is inserted into a crosshead die of an extruder and melted by a die having a predetermined shape. A first step of forming a molded article having a linear columnar portion extending linearly in the longitudinal direction after being extruded on the outer periphery of the inner conductor and then being cooled at a temperature lower than the melting point; A second step of transforming the linear columnar part into a spiral columnar part by applying a tension to the molded product while twisting by a device having a rotary take-up mechanism and a rotary take-up mechanism around the major axis. In addition, the first step and the second step are performed in a continuous or separate step.

  In the above manufacturing method, the apparatus including the rotary take-up mechanism and the rotary take-up mechanism in the second step can be constituted by a twisting machine such as a single twist machine or a double twist machine.

  Further, in the method for producing the thermoplastic resin spiral, a heating tank and a cooling tank are provided before and after the apparatus provided with the rotary take-up mechanism, and heated below the melting point of the thermoplastic resin, above the softening point, The twisted state can be fixed by cooling.

  Further, in the method for producing the thermoplastic resin spiral, the tension applied to the molded product is determined by the elongation of the inner conductor or the core material in front of the device having the rotary take-up mechanism and the rotary take-up mechanism. It can be adjusted within a range of 5% or less and 0.02% or more.

  Furthermore, in the said manufacturing method, the said internal conductor or core material can be selected from an annealed copper wire, an annealed copper wire plated with silver, tin or the like, or a stranded wire thereof.

  The present invention also relates to a thermoplastic resin spiral body having a plastically deformable inner conductor disposed in the center and a spiral columnar section formed of a thermoplastic resin disposed on the outer periphery of the inner conductor. The spiral columnar portion is formed by deforming the linear columnar portion into a spiral shape in a state where the inner conductor is plastically deformed, and the thermoplastic resin is selected from a fluorine resin, a polyolefin resin, and a cyclic polyolefin resin. A thermoplastic resin having a low dielectric constant is used.

  The spiral columnar part surrounding the inner conductor or the core material is formed with an annular part and the spiral columnar part provided on an outer periphery of the inner conductor with respect to a space surrounded by an outer diameter of the inner conductor and a circumscribed circle of the apex of the spiral columnar part. The proportion of the portion excluding the portion occupied by the insulating coating portion consisting of can be 50% or more.

  On the outer periphery of the thermoplastic resin spiral, an outer shield or a jacket in addition to the outer shield can be provided to form a coaxial cable.

  According to the method for manufacturing the thermoplastic resin spiral and the thermoplastic resin spiral having the above-described configuration, the thermoplastic resin spiral is manufactured without using the rotary die. Can solve various problems that occur in the process, and a highly accurate spiral can be obtained.

  Hereinafter, an embodiment in which the thermoplastic resin spiral according to the present invention is used as a core of a coaxial cable will be described. FIG. 1 shows an example of a thermoplastic resin spiral according to the present invention. The spiral object 10 shown in this figure includes an inner conductor 12 that can be plastically deformed, and an insulating coating layer 14 formed of a thermoplastic resin that covers the outer periphery of the inner conductor 12. In the case of this embodiment, since the spiral object 10 is used for the core for the coaxial cable, the inner conductor 12 is used. However, as a member for a communication cable such as an optical cable carrier (spacer) or a member for a communication electric wire. When used, the inner conductor 12 is called a core material.

  The insulating coating layer 14 is composed of an annular portion 14a that covers the outer periphery of the inner conductor 12, and a plurality (six) spiral columnar portions 14b that protrude radially from the outer periphery of the annular portion 14a. The helical object 10 having such a configuration is manufactured by the process shown in FIG.

  The manufacturing method shown in the figure is composed of a first step and a second step in a continuous state. In the first step, a plastically deformable conductive inner conductor (core material) 12 is inserted into a crosshead die 21 of a melt extruder 20, and a thermoplastic resin in a molten state is inserted into the outer periphery of the inner conductor 12 by a die having a predetermined shape. Then, the molded product 26 having the linear columnar portion 24 linearly extending in the longitudinal direction is continuously formed while being cooled by the cooling device 22 using cooling air.

  FIG. 3 shows a cross section of the molded product 26 obtained in the first step. In this embodiment, the linear columnar portions 24 are composed of six that extend radially at equal angular intervals. In the manufacturing method shown in FIG. 2, the inner conductor 12 is fed out from the creel 28 having a plurality of guide pulleys.

  On the other hand, the second step includes a tension roller 30, a rotary take-up machine 32, and a rotary take-up machine 34, and the tension taker 32 applies a predetermined tension to the molded product 26 by the rotary take-up machine 32. By rotating around the long axis, twisting is performed, and the linear columnar portion 24 of the molded product 26 is deformed into the helical columnar portion 14b, whereby the thermoplastic resin helical product 10 is obtained.

  In the case of the present embodiment, a hot air heating tank 36 for heating the thermoplastic resin of the molded product 26 to a temperature below the melting point and above the softening point is disposed after the tension roller 30, and behind the rotary take-up machine 32 is a cooling device. 38 is arranged.

  Note that what is arranged in front of the tension roller 30 is a Nelson-type take-up roller 40 in which a pair of rollers are provided at a predetermined interval in the vertical direction, and the molded product 26 is wound around the take-up roller 40. Later, by sending it out to the tension roller 30 side, the twist of the rotary take-up machine 32 is prevented from reaching the first step.

  In the embodiment shown in FIG. 2, the take-up roller 40 is arranged in order to perform the first process and the second process continuously, but the first process and the second process are not performed in a separate process. When performing, it replaces with the take-up roller 40 and is wound up by a winder (illustration omitted).

  When the spiral object 10 is manufactured by the process as described above, first, in the first process, since the linear columnar part 24 is formed, the inner conductor 12 can be coated at a high speed, and the linear columnar part 24 is inclined. A highly accurate molded product 26 is obtained. Subsequently, this shape (state) is maintained (not melted) and twisted to obtain a highly accurate spiral 10.

  The rotational speed of the rotary die is 100 rpm or less. However, in the rotary take-up machine 32 and the rotary winder 34, about 500 rpm is possible, and the productivity can be significantly improved. If a single twist or double twist twister is used instead of the rotary take-up machine 32 and the rotary winder 34 in the embodiment shown in FIG. 2, in this case, 1000 rpm or more is possible. The speed can be increased 5 times or more.

  The internal conductor 12 (core material) can be selected from an annealed copper wire, an annealed copper wire plated with silver, tin or the like, or a stranded wire thereof. An annealed copper wire has an elongation of 20 to 40%, is easily plastically deformed, can be kept in a straight line with a small tension when twisted, and requires less twisting force.

  In the case of a hard copper wire or a copper-clad steel wire, it may be difficult to keep it straight (with a force that can be processed) when twisting. From the above, a single wire of an annealed copper wire, a stranded wire, a single wire of a silver-plated annealed copper wire, a stranded wire, or a single wire of a tin-plated annealed copper wire and a stranded wire are preferable.

  When the inner conductor 12 (core material) is an annealed copper wire, it can be plastically deformed by being twisted to maintain a spiral shape. However, when the torsional rigidity is small, such as in the case of a thin stranded wire, the spiral (heat The twist may return due to the residual stress of the plastic resin) coating. In this case, the helical state can be stabilized by removing the residual stress by heating above the softening point and below the melting point.

  When the molded product 26 of the linear columnar portion 24 is twisted in a relaxed state, undulation occurs. In order to prevent the undulation, the tension roller 30 applies a predetermined tension to add a twist in a straight line state.

  The tension at this time varies depending on the type of the internal conductor 12, but when the elastic deformation region of the internal conductor 12 or the elastic deformation region is exceeded, the tension is adjusted within a range of 5% or less. In this case, 3% or less is more preferable. If it exceeds 5%, naturally, the change of the shape (of the spiral helix) from the linear state becomes large. Further, the inner conductor 12 (core material) may be stretched unevenly and the shape and pitch may be disturbed.

  If the tension is too high, the rib may be pressed against the roller surface when the passing direction is changed by the passing guide roller, and the shape may change (tilt) or be crushed. Further, the motor load of the (rotary) take-up machine 32 and the winder 34 becomes large, which is uneconomical.

  A fluorine resin is useful as a resin for forming the insulating coating layer 14, and the fluorine resin has a small dielectric constant and is suitable as a core for a coaxial cable. A copper pipe, metal tape (wrapping), etc. can be used as the outer conductor (shield), and a continuous air layer can be formed between the inner conductor 12 (core material) and the dielectric constant of the insulating coating layer 14 as a whole has jumped. Can be made small.

In addition, a spiral material using polyolefin or cyclic polyolefin having a low dielectric constant can drastically reduce the dielectric constant of the insulating coating layer 14 as a whole, and can reduce the material cost as well as the fluorine resin. It is easy to recycle and has excellent environmental characteristics.
Hereinafter, more specific examples of the present invention will be described together with comparative examples.

  A nozzle having a φ0.51 silver-plated annealed copper wire (inner conductor 12) to a crosshead die, an annular portion 24a covering the inner conductor in an annular shape, and six linear columnar portions extending radially outward from the annular portion PFA resin (Daikin Industries)

  A core (molded product 26) having six linear columnar portions 24b was obtained by covering with a product name NEOFLON PFA AP201). The diameter of the circumscribed circle passing through the tip of the columnar part 24b of the obtained molded product 26 is 1.40 mm, the coating thickness of the annular part 24a around the inner conductor 12 is 0.09 mm, and the rib thickness of the six columnar parts 24b Was 0.15 mm.

  Next, a back tension of 200 g corresponding to an elongation of 0.03% is heated to the surface temperature of the insulating coating layer 14 in the hot air heating tank 36 to the molded product 26 supplied while being applied with the tension roller 30. Then, the helical product 10 was obtained by cooling with air (cooling device 38) while taking up at 500 rpm and a speed of 7.5 m / min with the rotary take-up device 32 and the rotary take-up device 34.

  The obtained spiral object 10 was cut every 2 cm and the outer diameter of 10 cross sections was observed. The average outer diameter was 1.39 mm and the standard deviation was 7 μm. The twist pitch of the spiral object 10 was 15 mm. Moreover, when the cross-sectional shape was confirmed, the inclination of the rib was not seen. Further, when the state of the annealed copper wire was confirmed by peeling off the PFA coating, no undulation due to twisting occurred.

  Next, after the obtained spiral object 10 is inserted into a copper tube, the copper tube is squeezed with a die so that the insulating coating layer 14 and the copper tube are in close contact with each other, thereby producing a semi-rigid cable having an outer diameter of 1.78 mm. did.

  An SMA (Sub Miniature Type A) connector was attached to the cable, and the characteristic impedance was measured with a network analyzer (manufactured by Agilent: S-parameter vector network analyzer 8720ES). Next, when the reflection characteristics were measured, the 2 GHz voltage standing wave ratio (hereinafter referred to as VSWR) was 1.05 or less.

  A spiral product 10 was obtained under the same conditions as in Example 1 except that in the step of twisting the molded product 26, the back tension was changed to 600 g corresponding to an elongation of 0.1%. The obtained spiral product 10 had an average outer diameter of 1.38 mm and a standard deviation of 8 μm.

  The twist pitch of the ribs of the spiral object 10 was 15 mm. Moreover, the inclination of the rib by having twisted was not seen. Next, after the obtained spiral object 10 is inserted into a copper tube, the copper tube is squeezed with a die so that the insulating coating layer 14 and the copper tube are in close contact with each other, thereby producing a semi-rigid cable having an outer diameter of 1.78 mm. did.

  When the SMA connector was attached to the cable and the characteristic impedance was measured in the same manner as in Example 1, it was 50Ω. Next, when the reflection characteristic was measured, the VSWR at 2 GHz was 1.05 or less.

  A molded product 26 having an outer diameter of 1.45 mm was obtained in the same manner as in Example 1, except that the coating resin was changed from PFA to HDPE (Mitsui Chemicals, trade name: Hi-Zex 6600MA). The obtained molded product 26 had a coating thickness around the inner conductor 12 of 0.09 mm, and the rib thickness of the six linear columnar portions 24 was 0.15 mm.

  Next, the surface temperature of the insulating coating layer 14 is heated to 80 ° C. in the hot-air heating tank 36 with respect to the molded product 26 supplied while applying a back tension of 600 g corresponding to an elongation of 0.1%. 32. The helical product 10 was obtained by cooling with air while taking up at 500 rpm and a speed of 12.5 m / min with a rotary winder 34.

  The resulting spiral product 10 had an average outer diameter of 1.44 mm and a standard deviation of the outer diameter of 6 μm. The twist pitch of the spiral object 10 was 25 mm. Next, when the cross-sectional shape of the spiral object 10 was confirmed, the inclination of the rib was not seen. When the HDPE coating was peeled off and the state of the annealed copper wire was confirmed, no waviness due to twisting occurred.

  Next, a semi-rigid cable having a copper tube outer diameter of 1.84 mm was prepared in the same manner as in Examples 1 and 2 using the obtained spiral object 10. When the SMA connector was attached to the cable and the characteristic impedance of the cable was measured in the same manner as in Example 1, it was 51Ω. Next, when the reflection characteristic was measured, the VSWR at 2 GHz was 1.05 or less.

  In the step of twisting the molded product 26, a spiral product 10 was obtained in the same manner as in Example 3 except that the speed was 5 m / min. The obtained spiral product 10 had an average outer diameter of 1.44 mm and a standard deviation of the outer diameter of 7 μm.

  And the twist pitch of the rib of the helical object 10 was 10 mm. Moreover, when the cross-sectional shape of the spiral object 10 was observed, the rib was not inclined. Next, when the HDPE coating was peeled off and the state of the annealed copper wire was confirmed, no undulation was caused by being twisted.

  Next, the obtained spiral object 10 was used to obtain a semi-rigid cable having an outer diameter of 1.84 mm. When the SMA connector was attached to the obtained semi-rigid cable and the characteristic impedance was measured, it was 50Ω. Next, when the reflection characteristic was measured, the VSWR at 2 GHz was 1.05 or less.

Comparative Example 1

  A molded product was obtained in the same manner as in Example 1 except that the inner conductor was changed from φ0.51 silver-plated annealed copper wire to φ0.51 copper-coated steel wire. The diameter of the circumscribed circle passing through the tip of the columnar part of the obtained molded product was 1.40 mm, the coating thickness around the inner conductor was 0.09 mm, and the rib thickness of the six columnar parts was 0.15 mm.

  Next, as in Example 1, a spiral was obtained by applying a twist while applying a back tension of 200 g corresponding to an elongation of 0.01%. The average outer diameter of the obtained spiral product was 1.38 mm, and the standard deviation of the outer diameter was 10 μm.

  The pitch of the spiral was 15 mm. Next, when the PFA coating was peeled off and the state of the copper-clad steel wire was confirmed, the copper-clad steel wire was wavy. Next, a semi-rigid cable was produced in the same manner as in Example 1 using the spiral material. When this cable was checked by attaching an SMA connector, the characteristic impedance was 48Ω. Next, when the reflection characteristic was measured, the VSWR at 2 GHz exceeded 1.2.

Comparative Example 2

  A spiral product was obtained under the same conditions as in Example 1 except that the back tension when twisting the molded product with a rotary take-up machine was 4.1 kg corresponding to an elongation of 10%. The average outer diameter of the obtained spiral product was 1.33 mm, and the standard deviation of the outer diameter was 12 μm. When the cross-sectional shape was confirmed, a space was formed between the inner conductor and the PFA insulating layer, and the ribs were also inclined.

Comparative Example 3

  A φ0.51 silver-plated annealed copper wire is led to a rotating die rotating at 80 rpm, and passes through a nozzle having an annular part covering the inner conductor in an annular shape and six columnar parts extending radially outward from the annular part. Then, HDPE (trade name: Hi-Zex 6600MA) was coated and taken up at a speed of 2 m / min to obtain a spiral core. The average outer diameter of the obtained spiral core was 1.44 mm, the coating thickness around the inner conductor was 0.09 mm, and the rib thickness of the six columnar portions was 0.15 mm. The standard deviation of the outer diameter was 17 μm. When the cross section of the spiral core was observed, the rib was inclined. The helical pitch of the helical core was 25 mm.

Comparative Example 4

  A spiral object was produced under the same conditions as in Comparative Example 3 except that the take-up speed was 0.8 m / min. The average outer diameter of the spiral was 1.44 mm, the coating thickness around the inner conductor was 0.09 mm, and the rib thickness of the six columnar portions was 0.15 mm. The standard deviation of the outer diameter was 15 μm. When the cross section of the spiral core was observed, the rib was inclined. The helical pitch of the helical core was 10 mm.

Table 1 below summarizes the accuracy and manufacturing speed of the spirals of the above examples and comparative examples.

  According to the synthetic resin spiral product manufacturing method and the spiral product according to the present invention, a highly accurate spiral product can be manufactured at a high production rate, so that it can be effectively used for a coaxial cable or the like. it can.

It is a perspective view which shows one Example of the spiral product made from the thermoplastic resin concerning this invention. It is explanatory drawing of the manufacturing process of the helical product made from the thermoplastic resin concerning this invention. FIG. 3 is a cross-sectional explanatory view of a molded product obtained in the first step shown in FIG. 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Thermoplastic resin spiral body 12 Inner conductor 14 Insulation coating layer 14a Annular part 14b Helical columnar part 20 Extruder 22 Cooling device 24a Annular part 24b Linear columnar part 26 Molded product 30 Tension roller 32 Rotating take-up machine 34 Rotating winder

Claims (8)

Insert a plastically deformable conductive inner conductor or core material such as annealed copper wire, hard copper wire, copper-clad steel wire, etc. into the crosshead die of the extruder,
After a thermoplastic resin in a molten state is extruded on the outer periphery of the inner conductor with a die having a predetermined shape, the molded product having a linear columnar portion extending linearly in the longitudinal direction is taken up while being cooled at a temperature lower than the melting point. A first step to form,
A second step of transforming the linear columnar portion into a spiral columnar portion by winding while applying a twist by a device equipped with a rotary take-up mechanism and a rotary take-up mechanism while applying tension to the molded article; Including
The method for producing a helical product made of a thermoplastic resin, wherein the first step and the second step are performed in a continuous or separate step. 2. The thermoplastic resin helical material according to claim 1, wherein the device including the rotary take-up mechanism and the rotary take-up mechanism in the second step is a twisting machine such as a single twist machine or a double twist machine. Manufacturing method. In the manufacturing method of the thermoplastic resin spiral product according to claim 1,
A heating tank and a cooling tank are provided before and after the apparatus equipped with the rotary take-up mechanism, and the twisted state is fixed by heating and cooling below the melting point of the thermoplastic resin and above the softening point. The manufacturing method of the spiral body made from the thermoplastic resin of Claim 1 or 2. In the manufacturing method of the thermoplastic resin spiral product according to claim 1,
In front of the apparatus equipped with the rotary take-up mechanism and the rotary take-up mechanism, the tension applied to the molded product is adjusted within a range where the elongation of the inner conductor or the core material is 5% or less and 0.02% or more. The method for producing a thermoplastic resin spiral according to any one of claims 1 to 3.   5. The thermoplastic resin product according to claim 1, wherein the inner conductor or the core material is an annealed copper wire, an annealed copper wire plated with silver, tin, or the like, or a twisted wire thereof. A method for manufacturing a spiral object. A thermoplastic resin spiral having a plastically deformable inner conductor disposed at the center and a helical columnar portion formed of a thermoplastic resin disposed on the outer periphery of the inner conductor,
The spiral columnar portion is formed so that the linear columnar portion is spirally deformed in a state in which the inner conductor is plastically deformed,
A thermoplastic resin spiral product, wherein the thermoplastic resin is a thermoplastic resin having a small dielectric constant selected from a fluorine resin, a polyolefin resin, and a cyclic polyolefin resin.   The spiral columnar part surrounding the inner conductor or the core material is formed of an annular part provided on the outer periphery of the inner conductor and the spiral columnar part with respect to a space surrounded by an outer diameter of the inner conductor and a circumscribed circle of the apex of the spiral columnar part. The ratio of the part except the part which the insulation coating part which consists of these is occupied is 50% or more, The helical product made from the thermoplastic resin of Claim 6 characterized by the above-mentioned.   8. A thermoplastic resin spiral object comprising an outer shield or a jacket in addition to the outer shield on the outer periphery of the thermoplastic resin spiral object according to claim 6 or 7. .

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