Resin-coated superconducting wire, superconducting coil, and shield coil

Abstract

This resin-coated superconducting wire comprises a matrix resin made of a synthetic resin material, and a superconducting wire extending in the matrix resin. When viewed in a cross section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is greater than or equal to the cross-sectional area of the superconducting wire.

Description

Technical Field

[0001] The present disclosure relates to a resin-coated superconducting wire, a superconducting coil, and a shield coil.

Background Art

[0002] Conventionally, in applications such as nuclear magnetic resonance (NMR) devices and magnetic resonance imaging (MRI) examination devices, a superconducting material has been used as a shield coil for blocking the magnetic field from the outside to the inside to obtain appropriate analysis results and blocking the magnetic field from the inside to the outside to suppress the influence on the human body, electronic devices, etc.

[0003] As such a superconducting material, for example, as shown in FIG. 6, there is a resin-coated superconducting wire 2 in which a superconducting wire 22 such as NbTi wire is coated with a stabilizing copper 21 called a copper channel, and further coated with a resin braid such as polyester 23 around it. In such a resin-coated superconducting wire 2, by coating the periphery of the superconducting wire 22 with the stabilizing copper 21, the heat generated from the superconducting wire 22 is radiated to the outside, and its temperature rise is suppressed by immersing and cooling it in, for example, liquid helium.

[0004] In addition, in order to increase the heat generation efficiency of the superconducting material, Patent Document 1 proposes a superconducting wire in which a plurality of superconducting wires are embedded in stabilizing copper, coated with resin around it, and further embedded in stabilizing copper.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, all of the conventional superconducting materials described above use high-purity metals such as stabilizing copper around the superconducting wire, so they are relatively expensive, heavy, and tend to develop kinks, resulting in poor handling properties.

[0007] This disclosure has been made in view of the above circumstances, and an object thereof is to provide a resin-coated superconducting wire that is lighter, more flexible, and less expensive than conventional ones. [Means for Solving the Problems]

[0008] [1] A resin-coated superconducting wire having a matrix resin made of a synthetic resin material and a superconducting wire extending in the matrix resin, wherein, when viewed in the cross-section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or greater than the cross-sectional area of the superconducting wire. [2] The resin-coated superconducting wire according to [1] above, wherein the superconducting wire is made of one or more selected from the group consisting of metal / niobium titanium, metal / niobium trisulfide, metal / magnesium diboride, rare earth-based, and bismuth-based superconducting materials. [3] The resin-coated superconducting wire according to [1] or [2] above, wherein the synthetic resin material is a thermoplastic resin. [4] The resin-coated superconducting wire according to [3] above, wherein the melting point of the thermoplastic resin is 290°C or lower. [5] The resin-coated superconducting wire according to [3] or [4] above, wherein the melting point of the thermoplastic resin is 210°C or lower. [6] The resin-coated superconducting wire according to any one of [1] to [5] above, wherein the synthetic resin material is polyamide or polyolefin. [7] The resin-coated superconducting wire according to [6] above, wherein the polyamide is nylon. [8] The resin-coated superconducting wire according to any one of [1] to [7] above, wherein the synthetic resin material is nylon 11, nylon 12, or polyethylene. [9] The resin-coated superconducting wire according to any one of [1] to [5] above, wherein the synthetic resin material is an amorphous resin having a glass transition point of 250°C or lower.

[10] The resin-coated superconducting wire according to any one of [1] to [9] above, which is a multilayer coated wire composed of two or more matrix resin layers, wherein the matrix resin of the resin-coated superconducting wire is composed of an inner matrix resin layer covering the outer periphery of the superconducting wire and one or more outer matrix resin layers covering the outside of the inner matrix resin layer.

[11] The resin-coated superconducting wire according to

[10] above, wherein the inner matrix resin layer is an olefin resin or a copolymer thereof containing at least one functional group selected from the group consisting of an epoxy group, an oxazolyl group, an amino group, and a maleic anhydride residue.

[12] The resin-coated superconducting wire according to

[10] above, wherein the inner matrix resin layer is an olefin copolymer containing a metal salt of a carboxylic acid.

[13] The resin-coated superconducting wire according to any one of [1] to

[12] above, wherein the superconducting wire is a single wire.

[14] The resin-coated superconducting wire according to any one of [1] to

[12] above, wherein the superconducting wire is a stranded wire.

[15] The resin-coated superconducting wire according to any one of [1] to

[14] above, wherein the cross-sectional shape of the resin-coated superconducting wire is a rectangular shape.

[16] The resin-coated superconducting wire according to any one of [1] to

[14] above, wherein the cross-sectional shape of the resin-coated superconducting wire is a circular shape.

[17] The resin-coated superconducting wire according to any one of [1] to

[16] above, wherein the dimensional accuracy of the width and thickness of the resin-coated superconducting wire is ±0.10 mm or less.

[18] The resin-coated superconducting wire according to any one of [1] to

[17] above, wherein the dimensional accuracy of the width and thickness of the resin-coated superconducting wire is ±0.05 mm or less.

[19] A superconducting coil using the resin-coated superconducting wire according to any one of [1] to

[18] above.

[20] A shield coil using the resin-coated superconducting wire according to any one of [1] to

[18] above.

Advantages of the Invention

[0009] According to the present disclosure, a resin-coated superconducting wire that is lighter, more flexible, and less expensive than conventional ones can be provided.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0011] Hereinafter, preferred embodiments of the present disclosure will be described in detail, but the present disclosure is not limited to the following embodiments.

[0012] The inventors have found that a resin-coated superconducting wire has a matrix resin made of a synthetic resin material and a superconducting wire extending in the matrix resin, and that the cross-sectional area of the matrix resin is equal to or greater than the cross-sectional area of the superconducting wire when viewed in the cross-section of the resin-coated superconducting wire, whereby a resin-coated superconducting wire that is lighter, more flexible, and less expensive than conventional ones can be provided, and the present disclosure has been completed.

[0013] 1. Resin-coated superconducting wire The resin-coated superconducting wire according to the present disclosure has a matrix resin made of a synthetic resin material and a superconducting wire extending in the matrix resin. And in the resin-coated superconducting wire, when viewed in the cross section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or larger than the cross-sectional area of the superconducting wire.

[0014] FIG. 1 is a cross-sectional view of a resin-coated superconducting wire according to an embodiment, and FIG. 2 is a cross-sectional view of a resin-coated superconducting wire according to an embodiment. As shown in FIGS. 1 to 2, the resin-coated superconducting wire 1 has a matrix resin 11 made of a synthetic resin material and a superconducting wire 12 extending in the matrix resin 11. And in the present embodiment, when viewed in the cross section of the resin-coated superconducting wire 1, the cross-sectional area of the matrix resin 11 is equal to or larger than the cross-sectional area of the superconducting wire 12. Note that FIG. 1 shows a resin-coated superconducting wire 1 having a rectangular cross-sectional shape, and FIG. 2 shows a resin-coated superconducting wire 1 having a circular cross-sectional shape. Also, the resin-coated superconducting wire 1 shown in FIGS. 1 to 2 is a single-layer coated wire in which a matrix resin 11 composed of a single-layer matrix resin layer covers the outer periphery of the superconducting wire 12.

[0015] In the application of the shield coil, the current flowing through the inside of the superconducting wire 12 constituting the resin-coated superconducting wire 1 is relatively small. Therefore, the superconducting wire 12 used for such an application is less likely to cause a quench, and even if a quench occurs, since the current is small, it is not necessary to compound a large amount of stabilizing copper. On the other hand, in order to ensure the magnetic field shielding property of the shield coil, when the resin-coated superconducting wire 1 is wound as a coil, it is necessary to arrange the adjacent superconducting wires 12, 12 at a certain distance from each other. Therefore, the superconducting wire 12 is extended (preferably embedded) in a matrix resin 11 having a cross-sectional area of the same or larger cross section of the superconducting wire 12. Thereby, in the resin-coated superconducting wire, the matrix resin 11 serves as a so-called spacer, and the adjacent superconducting wires 12, 12 can be arranged at a certain distance from each other.

[0016] [Matrix resin] The matrix resin 11 is made of a synthetic resin material. The matrix resin 11 ensures the insulation between the superconducting wires 12 and, as described above, serves as a so-called spacer, arranging adjacent superconducting wires 12 at a certain distance from each other. Note that the matrix resin is in a solid state, excluding those formed by braiding threads.

[0017] As the matrix resin 11, it is preferably a thermoplastic resin capable of extrusion molding, which is an effective method for thick coating molding to make the cross-sectional area of the matrix resin 11 equal to or larger than the cross-sectional area of the superconducting wire 12 when viewed from the cross-section of the resin-coated superconducting wire 1. More preferably, it is a polyamide or a polyolefin. The polyamide is preferably nylon. The above-mentioned thermoplastic resin is preferably, for example, polyethylene, polypropylene, polystyrene, nylon 11, nylon 12, nylon 6, nylon 66, nylon 610, nylon MXD6 (a polycondensate of metaxylylenediamine and adipic acid), polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, tetrafluoroethylene - hexafluoropropylene copolymer resin (FEP), tetrafluoroethylene - ethylene copolymer resin (ETFE), polycarbonate, polyphenylene ether, polyetherimide, polyethersulfone, etc. These resins may be used alone or as a mixture of two or more resins.

[0018] Note that the synthetic resin material constituting the matrix resin 11 includes not only those composed only of synthetic resin but also resin compositions mainly composed of synthetic resin. This resin composition may contain various additives usually included in ordinary resin compositions, such as additives for improving mechanical or chemical durability, such as various fillers and antioxidants. For example, by adding a filler to the matrix resin 11, the thermal shrinkage rate of the matrix resin 11 can be made smaller and closer to the thermal shrinkage rate of the superconducting wire 12, and the heat cycle performance of the resin-coated superconducting wire 1 can be enhanced.

[0019] Further, when the matrix resin 11 is a crystalline resin, the melting point of the matrix resin 11 is preferably, for example, 290°C or lower, more preferably 280°C or lower, and even more preferably 270°C or lower. When manufacturing by heat-molding the raw material of the matrix resin 11, the lower the melting point of the resin serving as the raw material, the lower the temperature at which molding can be performed, and thus, deterioration of the performance of the superconducting wire 12 due to heating during molding can be suppressed.

[0020] Examples of the crystalline resin constituting the matrix resin 11 include polyethylene, polypropylene, nylon 11, nylon 12, nylon 6, nylon 66, nylon 610, nylon MXD6, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, tetrafluoroethylene - hexafluoropropylene copolymer resin (FEP), tetrafluoroethylene - ethylene copolymer resin (ETFE), etc., which are suitable.

[0021] From the viewpoint of further suppressing deterioration of the performance of the superconducting wire 12 due to heating during molding as described above, the melting point of the matrix resin 11 is preferably 210°C or lower, more preferably 200°C or lower, and even more preferably 190°C or lower. Among the above crystalline resins constituting the matrix resin 11, polyethylene, polypropylene, nylon 11, and nylon 12 are preferred.

[0022] The matrix resin 11 is preferably nylon or polyolefin. Among them, nylon 11, nylon 12, nylon 6, nylon 66, nylon 610, nylon MXD6, polyethylene, and polypropylene are more preferred. Particularly, nylon 11, nylon 12, polyethylene, and polypropylene are even more preferred because they have a low melting point, a low heat shrinkage rate, excellent water absorption resistance (low water absorption rate), flexibility, and mechanical properties.

[0023] Also, when the matrix resin 11 is an amorphous resin, the glass transition point of the synthetic resin material constituting the matrix resin 11 is preferably, for example, 250°C or lower, more preferably 240°C or lower, and even more preferably 230°C or lower. For example, when manufacturing by heat-molding the raw material of the matrix resin 11, the lower the glass transition point of the raw material, the lower the temperature at which resin coating molding can be performed, and thus, the change in the performance of the superconducting wire 12 due to heating during the molding process can be suppressed.

[0024] Examples of the amorphous resin constituting the matrix resin 11 include polycarbonate, polyphenylene ether, polyetherimide, polyethersulfone, etc., which are suitable.

[0025] FIG. 3 is a cross-sectional view of another example of a resin-coated superconducting wire (flat shape), and FIG. 4 is a cross-sectional view of another example of a resin-coated superconducting wire (circular shape). The resin-coated superconducting wire 1 shown in FIGS. 3 to 4 is a multi-layer coated wire in which a matrix resin 11 composed of multiple matrix resin layers covers the outer periphery of the superconducting wire 12. Specifically, in FIGS. 3 to 4, different from FIGS. 1 to 2, the matrix resin 11 is composed of an annular inner matrix resin layer 11a that covers the outer periphery of the superconducting wire 12 and one or more outer matrix resin layers 11b that cover the inner matrix resin layer 11a from the outside. In FIGS. 3 to 4, a two-layer structure in which the matrix resin 11 is composed of an inner matrix resin layer 11a and one outer matrix resin layer 11b is shown.

[0026] As shown in FIGS. 3 to 4, the resin-coated superconducting wire 1 is preferably a multi-layer coated wire having two or more matrix resin layers such as the inner matrix resin layer 11a and the outer matrix resin layer 11b, and more preferably a multi-layer coated wire having two to four matrix resin layers. By making the resin-coated superconducting wire 1 a multi-layer coated wire, it is expected to improve the dimensional accuracy of the extrusion-coated wire by reducing the amount of resin during single-pass extrusion coating. Furthermore, by using different resins for each matrix resin layer, the functionality of the resin-coated superconducting wire 1 can be further enhanced.

[0027] Specifically, in the case of polyolefin resins such as polyethylene and polypropylene with low adhesion to the superconducting wire 12, by making the inner matrix resin layer 11a, which is the first layer on the conductor side, an olefin resin containing at least one functional group selected from the group consisting of an epoxy group, an oxazolyl group, an amino group, and a maleic anhydride residue, or a copolymer thereof (also referred to as copolymer (A)), the adhesion between the superconducting wire 12 and the outer polyolefin resin 11b can be enhanced. Also, by making the multilayer coated wire such that the inner matrix resin layer 11a is an olefin copolymer containing a metal salt of a carboxylic acid (also referred to as olefin copolymer (B)), an improvement in adhesion similar to the above can be expected.

[0028] As the olefin component constituting the copolymer (A), ethylene, propylene, butene-1, pentene-1, 4-methylpentene-1, isobutylene, hexene-1, decene-1, octene-1, 1,4-hexadiene, dicyclopentadiene, etc. are suitable, and among them, preferably ethylene, propylene, and butene-1. These components may be used alone or in combination of two or more.

[0029] As the copolymer component other than the olefin constituting the copolymer (A), at least one of an acrylic component and a vinyl component may be used.

[0030] As the acrylic component, acrylic acid, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, isobutyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, etc. are suitable. As the vinyl component, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl chloride, vinyl alcohol, styrene, etc. are suitable. Among them, methyl acrylate and methyl methacrylate are more preferable. These components may be used alone or in combination of two or more. Representative preferred examples of the copolymer (A) include polyethylene or polypropylene grafted with maleic anhydride, and ethylene / glycidyl methacrylate copolymer, etc. As commercially available resins, there are Admer (trade name, manufactured by Mitsui Chemicals), Bondfast (trade name, manufactured by Sumitomo Chemical Industry Co., Ltd.), Rotader (trade name, manufactured by Atofina).

[0031] As the carboxylic acid constituting the olefin copolymer (B), preferably, unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, and unsaturated dicarboxylic acids such as maleic acid, fumaric acid, and phthalic acid can be mentioned. As the metal salts thereof, salts of Zn, Na, K, Mg, etc. can be mentioned. As such an olefin copolymer (B), preferably, a part of the carboxylic acid of an ethylene-methacrylic acid copolymer is made into a metal salt, and a resin generally called an ionomer (for example, Himilan; trade name, manufactured by Mitsui Polychemicals Co., Ltd.) can be mentioned.

[0032] The matrix resin 11 preferably has a heat shrinkage rate calculated by the following method of 5% or less, more preferably 2% or less, and even more preferably 1% or less. Thereby, when the matrix resin 11 is immersed in a refrigerant such as liquid helium, damage and deterioration of the matrix resin 11 can be suppressed.

[0033] (Method for calculating heat shrinkage rate) 0.2 g of the resin-coated superconducting wire 1 cut out in the longitudinal direction of the resin-coated superconducting wire 1 was immersed in 500 mL of liquid helium for several minutes, the dimensions of the resin-coated superconducting wire 1 were measured, and the thermal shrinkage rate was calculated by the following formula (1). Thermal shrinkage rate (%) = {(Dimension of the resin-coated superconducting wire before immersion - Dimension of the resin-coated superconducting wire after immersion) / Dimension of the resin-coated superconducting wire before immersion} × 100 ··· Formula (1)

[0034] As the matrix resin 11, it is more preferable that the water absorption rate calculated by the following method is 1.0% or less, and further preferably 0.7% or less. The lower the water absorption rate, the less the surface expansion of the matrix resin 11. Therefore, it is possible to suppress damage and deterioration due to water absorption of the matrix resin 11, and a decrease in mechanical strength due to alteration and crack generation of the matrix resin 11 due to water absorption. The calculation method shown below is one of the methods for obtaining the water absorption rate of plastics defined in JIS K7209.

[0035] (Calculation method of water absorption rate) 1.0 g of the resin-coated superconducting wire 1 cut out in the longitudinal direction of the resin-coated superconducting wire 1 was immersed in 500 mL of water at 23°C for 24 hours, then the water on the surface was wiped off, the mass of the resin-coated superconducting wire 1 was measured, and the water absorption rate was calculated by the following formula (2). Water absorption rate (%) = {(Mass of the resin-coated superconducting wire before immersion - Mass of the resin-coated superconducting wire after immersion) / Mass of the resin-coated superconducting wire before immersion} × 100 ··· Formula (2)

[0036] [Superconducting wire] The superconducting wire 12 is a wire extending in the above-described matrix resin 11 and has superconductivity.

[0037] As the size of the cross-section of the superconducting wire 12, for example, if it is circular, it is preferably 0.05 to 2.00 mmφ, more preferably 0.07 to 1.50 mmφ, and even more preferably 0.1 to 1.0 mmφ. Also, if the cross-section of the superconducting wire 12 is rectangular, the long side is preferably 0.8 mm to 2.5 mm, more preferably 1.5 mm to 2.0 mm, the short side is preferably 0.5 mm to 1.5 mm, and more preferably 0.9 mm to 1.2 mm.

[0038] The superconducting wire 12 is preferably composed of one or more superconducting materials selected from the group consisting of, for example, metal / niobium titanium, metal / niobium trisulfide, metal / magnesium diboride, rare earth-based, and bismuth-based superconducting materials. Note that "metal / niobium titanium", "metal / niobium trisulfide", or "metal / magnesium diboride" is a composite formed by coating a metal such as copper or iron around niobium titanium, niobium trisulfide, or magnesium diboride.

[0039] Specifically, examples of rare earth-based materials include YBa2Cu3O 7-δ , GdBa2Cu3O 7-δ and the like. Examples of bismuth-based materials include Bi2Sr2Ca2Cu3O 10+δ , Bi2Sr2CaCu2O 8+δ and the like.

[0040] As the superconducting wire 12, either a single wire or a stranded wire formed by twisting a plurality of strands can be used.

[0041] [Relationship between the matrix resin and the superconducting wire] As described above, in the resin-coated superconducting wire 1, when viewed in terms of its cross-section, the cross-sectional area of the matrix resin 11 is equal to or greater than the cross-sectional area of the superconducting wire 12.

[0042] Also, when viewed in the cross-section of the resin-coated superconducting wire 1, the ratio of the cross-sectional area of the matrix resin 11 to the cross-sectional area of the superconducting wire 12 (the ratio of the cross-sectional area of the matrix resin 11 / the cross-sectional area of the superconducting wire 12) is preferably 2 times or more, more preferably 5 times or more, even more preferably 10 times or more, particularly preferably 20 times or more, and most preferably 40 times or more. The upper limit of the ratio of the cross-sectional areas is preferably 1000 times from a practical perspective such as the suitability as a coil material and the handling property of the winding operation.

[0043] Also, when the resin-coated superconducting wire 1 is viewed in cross-section, in FIGS. 1 to 2, the superconducting wire 12 is shown to be located at the center (center of gravity) of the matrix resin 11. However, as long as it does not expose from the surface of the resin-coated superconducting wire (as long as there is even a slight amount of the resin component of the matrix resin 11 on the surface of the resin-coated superconducting wire), it may be located at any position in the matrix resin 11. For example, FIGS. 5(a) to (f) show modified examples of the cross-sections of the resin-coated superconducting wires 1A to 1F having a rectangular cross-sectional shape, in which the superconducting wires 12A to 12F are arranged at different cross-sectional positions of the matrix resins 11A to 11F, respectively.

[0044] In the resin-coated superconducting wire, one superconducting wire 12 is arranged as a single wire or a stranded wire with respect to one matrix resin 11.

[0045] The resin-coated superconducting wire can have any cross-sectional shape such as a circular shape including an elliptical shape, a triangular shape, a square shape, a rectangular shape, etc. However, from the viewpoint of ease of forming a coil, a rectangular shape is preferable. When the cross-sectional shape of the resin-coated superconducting wire is a rectangular shape, the cross-sectional shape of the resin-coated superconducting wire includes those having an R value of 1 mm or less at the corners.

[0046] When the resin-coated superconducting wire is rectangular, the long side of the cross-section of the resin-coated superconducting wire is preferably, for example, 0.5 mm to 10 mm, and more preferably 1 mm to 7 mm. Further, the short side of the cross-section of the resin-coated superconducting wire is preferably, for example, 0.1 mm to 5 mm, and more preferably 0.5 mm to 3 mm.

[0047] The dimensional accuracy of the width and thickness of the resin-coated superconducting wire is preferably ±0.10 mm or less, and more preferably ±0.05 mm or less. Note that the "dimensional accuracy" refers to the range of the difference between the maximum value and the minimum value of the dimensions in one resin-coated superconducting wire. By having such dimensional accuracy, the resin-coated superconducting wire can achieve higher electromagnetic shielding performance. In order to achieve such dimensional accuracy, a method of shaving the outer surface after resin extrusion processing can be mentioned. Further, a method of coating, for example, a UV curable resin material on the surface of the above-described matrix resin can also be mentioned.

[0048] The resin-coated superconducting wire as described above can be applied to a superconducting coil, particularly to a shield coil used in an NMR apparatus, an MRI examination apparatus, or the like.

[0049] The voltage that can be applied to the resin-coated superconducting wire as described above is not particularly limited, but is preferably, for example, 0 to 50 V, more preferably 0 to 20 V, and even more preferably 0 to 10 V.

[0050] Further, the resin-coated superconducting wire is lighter and cheaper than the conventional superconducting wire provided with stabilized copper. Furthermore, it is less likely to develop a bend and has improved flexibility, and is excellent in flexibility such as flexibility, so it has good handling properties and is easy to wind when coiled.

[0051] 2. Manufacturing method of resin-coated superconducting wire The resin-coated superconducting wire of the above-described embodiment can be manufactured, for example, by inserting the superconducting wire into the synthetic resin raw material constituting the matrix resin and performing extrusion molding in the same manner as the manufacturing method of an extrusion molded body of a normal resin material. The heating temperature, extrusion speed, etc. may be appropriately adjusted according to the type of the synthetic resin raw material, the size and shape of the molded body to be molded, etc.

[0052] Also, in the prior art, after previously resin-coating the superconducting wire which is a strand wire, it had gone through a two-step process of embedding it in a copper channel. On the other hand, in the resin-coated superconducting wire of the embodiment, since the matrix resin can be formed into the same shape as the copper channel, the conventional two-step process can be finished in one step.

Example

[0053] Next, in order to further clarify the effects of the present disclosure, examples will be described, but the present disclosure is not limited to these examples.

[0054] (Examples 1 to 40) Using nylon 11 (manufactured by ARKEMA, BESN Noir TL), nylon 12 (manufactured by Ube Industries, UBESTA3030LUX), nylon 6 (manufactured by Ube Industries, UBESTA1024JI), nylon 66 (manufactured by Asahi Kasei, LEONA (registered trademark) 1300S), high-density polyethylene (manufactured by Asahi Kasei, SUNTECH (registered trademark)-HD B891) as raw materials of the synthetic resin material, a 0.3 mmφ copper / niobium titanium superconducting wire was inserted into the raw materials of the synthetic resin material, and extrusion processing was performed under temperature conditions of +20°C or more and +80°C or less than the melting point of each resin material, using a mold having a rectangular shape (Examples 1 to 20) or a circular shape (Examples 21 to 40) and having the dimensions shown in Tables 2 and 3 below. The arrangement of the superconducting wire was arranged so as to be at the center of the synthetic resin material as shown in FIGS. 1 and 2. In Examples 1 to 20, a resin-coated superconducting wire having a rectangular cross-sectional shape was manufactured. In Examples 21 to 40, a resin-coated superconducting wire having a circular cross-sectional shape was manufactured.

[0055] (Example 41) Using high-density polyethylene (manufactured by Asahi Kasei Corporation, Suntech (registered trademark) - HD B891) as the raw material of the synthetic resin material, a modified low-density polyethylene (manufactured by Mitsui Chemicals, Admer NB508) obtained by graft copolymerization of maleic anhydride was coated on a 0.3 mmφ copper / niobium titanium superconducting wire with a thickness of 20 μm, and the wire was inserted into the raw material of the synthetic resin material. Using a mold that is flat and has the dimensions shown in Table 4 below, extrusion processing was performed under temperature conditions of +20°C or higher and +80°C or lower than the melting point of each resin material. The arrangement of the superconducting wire was arranged so as to be at the center of the synthetic resin material, as shown in Fig. 3.

[0056] (Example 42) A resin-coated superconducting wire was obtained in the same manner as in Example 41, except that a 0.3 mmφ copper / niobium titanium superconducting wire coated with an ethylene-methacrylic acid copolymer (manufactured by Mitsui Polychemicals Co., Ltd., Himilan 1855) in which a part of the carboxylic acid was made into a metal salt with a thickness of 20 μm was used.

[0057] (Example 43) Using high-density polyethylene (manufactured by Asahi Kasei Corporation, Suntech (registered trademark) - HD B891) as the raw material of the synthetic resin material, a modified low-density polyethylene (manufactured by Mitsui Chemicals, Admer NB508) obtained by graft copolymerization of maleic anhydride was coated on a 0.3 mmφ copper / niobium titanium superconducting wire with a thickness of 20 μm, and the wire was inserted into the raw material of the synthetic resin material. Using a mold that is round and has the dimensions shown in Table 5 below, extrusion processing was performed under temperature conditions of +20°C or higher and +80°C or lower than the melting point of each resin material. The arrangement of the superconducting wire was arranged so as to be at the center of the synthetic resin material, as shown in Fig. 4.

[0058] The cross-sectional area of the matrix resin was calculated from the difference between the cross-sectional area of the outer shape obtained from the outer dimensions of the resin-coated superconducting wire and the cross-sectional area of the superconducting wire as seen in the cross-section of the resin-coated superconducting wire. From the cross-sectional area of this matrix resin, the mass and cost of the resin per 1000 m of the length of the resin-coated superconducting wire, and their copper conversion values were calculated. The results are shown in Tables 2 to 5 below. In Tables 2 to 5, the values in parentheses indicate the copper conversion amounts in the same volume.

[0059] Also, for each of the synthetic resin materials used in Examples 1 to 43, the melting point, glass transition point, thermal shrinkage rate, and water absorption rate are shown in Table 1 respectively. The thermal shrinkage rate and water absorption rate were determined by the methods described above.

[0060] [Table 1]

[0061] [Table 2]

[0062] [Table 3]

[0063] [Table 4]

[0064] [Table 5]

[0065] For the resin-coated superconducting wires of Examples 1 to 43, it was confirmed that they can be obtained with the same dimensions as the superconducting wires using the conventional copper channel, and thereby achieve the same magnetic shielding characteristics as the superconducting wires using the conventional copper channel.

[0066] Furthermore, as shown in Tables 2 to 5 above, it was found that the resin-coated superconducting wires of Examples 1 to 43 can achieve a significant reduction in mass and raw material costs compared to the copper-coated superconducting wires. [Explanation of Reference Signs]

[0067] 1, 1A, 1B, 1C, 1D, 1E, 1F, 2 Resin-coated superconducting wire 11, 11A, 11B, 11C, 11D, 11E, 11F Matrix resin 11a Inner matrix resin layer 11b Outer matrix resin layer 12, 12A, 12B, 12C, 12D, 12E, 12F, 22 Superconducting wire 21 Stabilized copper

Claims

1. A resin-coated superconducting wire having a matrix resin made of a synthetic resin material and a superconducting wire extending in the matrix resin, wherein, when viewed in the cross section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or larger than the cross-sectional area of the superconducting wire, the synthetic resin material is a thermoplastic resin having a melting point of 290°C or lower, and is at least one resin selected from the group consisting of polypropylene, polystyrene, nylon 11, nylon 12, nylon 6, nylon 66, nylon 610, nylon MXD6 (a polycondensate of metaxylylenediamine and adipic acid), polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, tetrafluoroethylene / hexafluoropropylene copolymer resin (FEP), and tetrafluoroethylene / ethylene copolymer resin (ETFE), and the resin-coated superconducting wire is a multi-layer coated wire composed of two or more matrix resin layers including an inner matrix resin layer in which the matrix resin covers the outer periphery of the superconducting wire and one or more outer matrix resin layers covering the outside of the inner matrix resin layer.

2. A resin-coated superconducting wire having a matrix resin made of a synthetic resin material and a superconducting wire extending in the matrix resin, wherein, when viewed in the cross section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or larger than the cross-sectional area of the superconducting wire, the synthetic resin material is a thermoplastic resin having a melting point of 290°C or lower, and is at least one resin selected from the group consisting of polypropylene, polystyrene, nylon 11, nylon 12, nylon 6, nylon 66, nylon 610, nylon MXD6 (a polycondensate of metaxylylenediamine and adipic acid), polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, tetrafluoroethylene / hexafluoropropylene copolymer resin (FEP), and tetrafluoroethylene / ethylene copolymer resin (ETFE), and the superconducting wire is a stranded wire.

3. A resin-coated superconducting wire having a matrix resin made of a synthetic resin material and a superconducting wire extending in the matrix resin, wherein, ​ ​ When viewed in the cross-section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or greater than the cross-sectional area of the superconducting wire. The synthetic resin material is a thermoplastic resin having a melting point of 290°C or lower, and is one or more resins selected from the group consisting of polypropylene, polystyrene, nylon 11, nylon 12, nylon 6, nylon 66, nylon 610, nylon MXD6 (a polycondensate of metaxylylenediamine and adipic acid), polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, tetrafluoroethylene / hexafluoropropylene copolymer resin (FEP), and tetrafluoroethylene / ethylene copolymer resin (ETFE). A resin-coated superconducting wire, characterized in that the cross-sectional shape of the resin-coated superconducting wire is a flat angle shape.

4. A matrix resin made of a synthetic resin material, and a superconducting wire extending in the matrix resin constitute a resin-coated superconducting wire, wherein, when viewed in the cross-section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or greater than the cross-sectional area of the superconducting wire. A superconducting coil using a resin-coated superconducting wire, wherein the synthetic resin material is a thermoplastic resin having a melting point of 290°C or lower, and is one or more resins selected from the group consisting of polypropylene, polystyrene, nylon 11, nylon 12, nylon 6, nylon 66, nylon 610, nylon MXD6 (a polycondensate of metaxylylenediamine and adipic acid), polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, tetrafluoroethylene / hexafluoropropylene copolymer resin (FEP), and tetrafluoroethylene / ethylene copolymer resin (ETFE).

5. A matrix resin made of a synthetic resin material, and a superconducting wire extending in the matrix resin constitute a resin-coated superconducting wire, wherein, when viewed in the cross-section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or greater than the cross-sectional area of the superconducting wire. The resin-coated superconducting wire uses a resin-coated superconducting wire in which the synthetic resin material is a thermoplastic resin having a melting point of 290° C. or lower, and is one or more resins selected from the group consisting of polypropylene, polystyrene, nylon 11, nylon 12, nylon 6, nylon 66, nylon 610, nylon MXD6 (a polycondensate of metaxylylenediamine and adipic acid), polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyphenylene sulfide, tetrafluoroethylene / hexafluoropropylene copolymer resin (FEP), and tetrafluoroethylene / ethylene copolymer resin (ETFE).

6. The resin-coated superconducting wire according to any one of claims 1 to 3, wherein the superconducting wire is composed of one or more selected from the group consisting of metal / niobium titanium, metal / niobium trisulfide, metal / magnesium diboride, rare earth-based, and bismuth-based superconducting materials.

7. The resin-coated superconducting wire according to any one of claims 1 to 3 and 6, wherein the melting point of the thermoplastic resin is 210° C. or lower.

8. A resin-coated superconducting wire having a matrix resin made of a synthetic resin material and a superconducting wire extending in the matrix resin, wherein, when viewed in the cross section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or larger than the cross-sectional area of the superconducting wire, the synthetic resin material is an amorphous resin having a glass transition point of 250° C. or lower, and is one or more resins selected from the group consisting of polycarbonate, polyphenylene ether, polyetherimide, and polyethersulfone, the resin-coated superconducting wire is a multilayer-coated wire composed of two or more matrix resin layers including an inner matrix resin layer that covers the outer periphery of the superconducting wire and one or more outer matrix resin layers that cover the outside of the inner matrix resin layer.

9. A resin-coated superconducting wire having a matrix resin made of a synthetic resin material and a superconducting wire extending in the matrix resin, wherein, when viewed in the cross section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or larger than the cross-sectional area of the superconducting wire, ​ ​ The synthetic resin material is an amorphous resin having a glass transition point of 250° C. or lower, and is one or more resins selected from the group consisting of polycarbonate, polyphenylene ether, polyetherimide, and polyethersulfone. A resin-coated superconducting wire, characterized in that the superconducting wire is a stranded wire.

10. A matrix resin made of a synthetic resin material, A superconducting wire extending in the matrix resin A resin-coated superconducting wire having, When viewed in the cross section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or greater than the cross-sectional area of the superconducting wire. The synthetic resin material is an amorphous resin having a glass transition point of 250° C. or lower, and is one or more resins selected from the group consisting of polycarbonate, polyphenylene ether, polyetherimide, and polyethersulfone. A resin-coated superconducting wire, characterized in that the cross-sectional shape of the resin-coated superconducting wire is a rectangular shape.

11. A matrix resin made of a synthetic resin material, A superconducting wire extending in the matrix resin A resin-coated superconducting wire having, When viewed in the cross section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or greater than the cross-sectional area of the superconducting wire. A superconducting coil using a resin-coated superconducting wire, wherein the synthetic resin material is an amorphous resin having a glass transition point of 250° C. or lower, and is one or more resins selected from the group consisting of polycarbonate, polyphenylene ether, polyetherimide, and polyethersulfone.

12. A matrix resin made of a synthetic resin material, A superconducting wire extending in the matrix resin A resin-coated superconducting wire having, When viewed in the cross section of the resin-coated superconducting wire, the cross-sectional area of the matrix resin is equal to or greater than the cross-sectional area of the superconducting wire. A shield coil using a resin-coated superconducting wire, wherein the synthetic resin material is an amorphous resin having a glass transition point of 250° C. or lower, and is one or more resins selected from the group consisting of polycarbonate, polyphenylene ether, polyetherimide, and polyethersulfone.

13. The resin-coated superconducting wire according to claim 1 or 8, wherein the inner matrix resin layer is an olefin-based resin or a copolymer thereof containing at least one functional group selected from the group consisting of an epoxy group, an oxazolyl group, an amino group, and a maleic anhydride residue.

14. The resin-coated superconducting wire according to claim 1 or 8, wherein the inner matrix resin layer is an olefin copolymer containing a metal salt of a carboxylic acid.

15. The resin-coated superconducting wire according to any one of claims 1, 3, 6 to 8, 10, 13 to 14, wherein the superconducting wire is a single wire.

16. The resin-coated superconducting wire according to any one of claims 1 to 2, 6 to 9, 13 to 14, wherein a cross-sectional shape of the resin-coated superconducting wire is circular.

17. The resin-coated superconducting wire according to any one of claims 1 to 3, 6 to 10, 13 to 16, wherein dimensional accuracy of a width and a thickness of the resin-coated superconducting wire is ±0.10 mm or less.

18. The resin-coated superconducting wire according to any one of claims 1 to 3, 6 to 10, 13 to 17, wherein dimensional accuracy of a width and a thickness of the resin-coated superconducting wire is ±0.05 mm or less.

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