Ridge magnetometer

Abstract

This thermally insulated container (10) comprises an inner container (11) and an outer container (14) that envelops the inner container (11) with a gap (15) therebetween. The inner container (11) and the outer container (14) are formed from a fiber-reinforced plastic obtained by impregnating a substrate with a resin. The inner container (11) comprises: a cylindrical container (13) and a second cylindrical container (22) that have an accommodation section (23) and an accommodation section (24) for internally storing a refrigerant (16); and a refrigerant injection tube (12) that injects the refrigerant (16). The accommodation section (24) is in communication with the accommodation section (23). A substrate that forms a prescribed region of the second cylindrical container (22) and a prescribed region of the outer container (14) includes a fabric. The prescribed region of the outer container (14) further includes a honeycomb sheet.

Description

[Technical field]

[0001] The present invention relates to a thermally insulated container and a magnetospinograph using the same. [Background technology]

[0002] In the medical field, a device (magnetospinometer) has been developed to measure the magnetic field generated by nerve activity in the spinal cord. The magnetospinometer uses a superconducting quantum interference device (SQUID) that utilizes the principle of superconductivity to measure the weak magnetic field generated in the spinal cord.

[0003] In order to realize the superconducting state, the SQUID must be immersed in a coolant such as liquid helium. For this reason, the SQUID requires a highly insulating container that can store the coolant for a long time. Furthermore, the material that makes up the insulating container must be nonmagnetic and not affected by magnetism.

[0004] For example, Patent Document 1 discloses a cryogenic container including an inner container made of fiber reinforced plastics (hereinafter also referred to as "FRP") and an outer container surrounding the inner container, and a magnetic detection device including the cryogenic container. The inner container is filled with a liquid having a low boiling point, and a magnetic detection sensor is disposed in the liquid. The gap between the inner container and the outer container is in a vacuum state. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 7-302933 Summary of the Invention [Problem to be solved by the invention]

[0006] In order to measure weak magnetic fields, it is necessary to shorten the distance (lift-off) between the SQUID and the measurement site on the spinal cord as much as possible. In particular, the insulating container between the SQUID and the measurement site on the spinal cord needs to have a thin wall while still maintaining its insulating function.

[0007] The inner and outer containers disclosed in Patent Document 1 have thick walls to enhance the heat insulating function, which makes it difficult for the SQUID to sense weak magnetic fields.

[0008] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide an insulating container having excellent insulating properties and a thin wall, and a magnetospinograph using the same. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, [1] the insulated container of the present invention comprises an inner container and an outer container surrounding the inner container via a gap, the inner container and the outer container being made of fiber-reinforced plastic in which a base material containing fiber is impregnated with resin, the inner container comprises a cylindrical container and a second cylindrical container each having a storage portion for storing a refrigerant therein, and a refrigerant injection tube for injecting the refrigerant into the cylindrical container, the storage portion of the second cylindrical container is connected to the storage portion of the cylindrical container, the base material constituting a predetermined region of the second cylindrical container and a predetermined region of the outer container comprises a woven fabric, the predetermined region of the outer container further comprises a honeycomb sheet, and the woven fabric is laminated on one side and the other side of the honeycomb sheet.

[0010] [2] The woven fabric may be made of at least one fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber.

[0011] Furthermore, [3] the base material constituting the specified region of the outer container may further include a unidirectional fiber sheet in which a plurality of fibers are aligned in one direction, and the unidirectional fiber sheet may be laminated on at least one of the two surfaces of the honeycomb sheet.

[0012] [4] The fibers of the unidirectional fiber sheet constituting the specified region of the outer container may be parallel to the extending direction of the axis of the second cylindrical container.

[0013] [5] In addition, the base material constituting the specified region of the second cylindrical container may further include a unidirectional fiber sheet formed by aligning a plurality of fibers in one direction.

[0014] [6] In addition, the fibers of the unidirectional fiber sheet constituting the specified region of the second cylindrical container may be perpendicular to the extending direction of the axis of the second cylindrical container.

[0015] [7] In addition, the outer container may surround the second cylindrical container in a state in which the unidirectional fiber sheet constituting the specified area of ​​the outer container and the unidirectional fiber sheet constituting the specified area of ​​the second cylindrical container face each other.

[0016] [8] The unidirectional fiber sheet constituting the predetermined region of the outer container may be made of at least one fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber.

[0017] [9] The unidirectional fiber sheet constituting the predetermined region of the second cylindrical container may be made of at least one fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber.

[0018]

[10] The honeycomb sheet may have a thickness of 1 to 7 mm.

[0019]

[11] The resin may include an epoxy resin.

[0020]

[12] The spinal magnetometer according to the present invention comprises a superconducting quantum interferometer for detecting a magnetic field generated from a living body, and an insulated container described in any one of [1] to

[11] , wherein the superconducting quantum interferometer is immersed in a refrigerant stored in the storage portion of the second cylindrical container. Effect of the Invention

[0021] According to the present invention, it is possible to provide an insulating container having excellent heat insulation properties and a thin wall, and a magnetospinometer using the same. [Brief description of the drawings]

[0022] [Figure 1] 1 is a schematic side view of an insulated container according to an embodiment of the present invention. [Diagram 2] 1 is a schematic top view of an insulated container according to an embodiment of the present invention. [Diagram 3] FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. [Figure 4] 4 is a schematic diagram showing the configuration of the refrigerant injection pipe shown in FIG. 3. [Diagram 5] FIG. 2 is a schematic diagram showing the configuration of a unidirectional fiber sheet. [Figure 6] 4 is a schematic diagram showing the configuration of a cylindrical part of the cylindrical container shown in FIG. 3. [Figure 7] 4 is a schematic cross-sectional view showing the configuration of a modified example of the cylindrical portion of the cylindrical container shown in FIG. [Figure 8] FIG. 3 is a cross-sectional view taken along line BB in FIG. 2. [Figure 9] 1 is a schematic cross-sectional view of a magnetospinograph using a heat-insulating container according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The following is a detailed description of an insulated container according to an embodiment of the present invention and a magnetospinograph using the same. The following embodiments are merely examples for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be practiced with appropriate modifications within the scope of its gist.

[0024] (Embodiment) An insulated container 10 according to an embodiment will be described. Fig. 1 is a side view of the insulated container 10. Fig. 2 is a top view of the insulated container 10. Fig. 3 is a cross-sectional view taken along line AA of the insulated container 10 shown in Fig. 2. As shown in Fig. 3, the insulated container 10 is a container for storing a refrigerant 16. The insulated container 10 includes an inner container 11 and an outer container 14 that surrounds the inner container 11 with a gap 15 therebetween.

[0025] The inner container 11 and the outer container 14 will now be described.

[0026] [Inner container 11] The inner container 11 comprises a cylindrical container 13 having a storage section 23 for storing the refrigerant 16 therein, a refrigerant injection tube 12 attached to the cylindrical container 13, and a second cylindrical container 22 having a storage section 24 for storing the refrigerant 16 therein. The storage section 24 is connected to the storage section 23. The cylindrical container 13 has an upper surface section 131 constituting the upper surface, a cylindrical section 132 constituting the side wall, and a bottom surface section 133 constituting the bottom surface. The refrigerant injection tube 12 is attached to the upper surface section 131. The refrigerant injection tube 12 may be attached to the cylindrical section 132. Here, the "inside" of the inner container 11 refers to the area constituted by the surfaces with which the refrigerant 16 may come into contact.

[0027] The refrigerant injection pipe 12, the cylindrical container 13 and the second cylindrical container 22 will be described.

[0028] [Refrigerant injection pipe 12] The refrigerant injection pipe 12 is a pipe for injecting the refrigerant 16 into the cylindrical container 13. The pipe may be configured in a cylindrical shape, an elliptical cylindrical shape, a rectangular cylindrical shape, or the like.

[0029] From the viewpoint of improving thermal insulation and of exhibiting rigidity at room temperature and in the temperature range of -196°C or less achieved by refrigerant 16, the thickness of the wall constituting refrigerant injection tube 12 is preferably 2 to 30 mm, and more preferably 2.5 to 15 mm. Hereinafter, the "temperature range of -196°C or less" will be referred to as the "cryolow temperature range." Moreover, the thickness of the wall constituting refrigerant injection tube 12 refers to the thickness of the wall constituting refrigerant injection tube 12 in a plane perpendicular to the longitudinal direction (height direction) of refrigerant injection tube 12.

[0030] The length of the refrigerant injection pipe 12 is set according to the sizes of the outer container 14 and the inner container 11, and is, for example, 100 to 500 mm.

[0031] When refrigerant injection pipe 12 has a cylindrical shape, the diameter (inner diameter) of refrigerant injection pipe 12 is, from the viewpoint of suppressing evaporation of refrigerant 16, for example, 50 to 300 mm.

[0032] When refrigerant injection pipe 12 has an elliptical cylindrical shape, the length of its major axis is, for example, 50 to 300 mm.

[0033] When refrigerant injection tube 12 has a rectangular cylindrical shape, the length of its diagonal in the cross section of the tube in a plane perpendicular to the longitudinal direction (height direction) of refrigerant injection tube 12 is, for example, 100 to 400 mm.

[0034] Refrigerant injection pipe 12 is made of fiber reinforced plastics (hereinafter referred to as “FRP”) that is made up of a base material 21 and a resin impregnated into base material 21.

[0035] Here, the cured state of the resin constituting the FRP is a state in which the curing reaction has progressed completely (hereinafter also referred to as the "C stage state"). Unless otherwise specified in the following description, the cured state of the FRP is the C stage state. This also applies to other embodiments.

[0036] The FRP base material 21 constituting the refrigerant injection tube 12 is composed of at least one type selected from the group consisting of glass fiber, alumina fiber, and carbon fiber. From the viewpoints of cost, processability, and availability, and from the viewpoint of reducing thermal conductivity in the normal temperature to cryogenic temperature range, the base material 21 is preferably made of glass fiber.

[0037] 4, the fibers constituting substrate 21 are wound helically in the extension direction of axial core CL of refrigerant injection tube 12 in order to slow down the conduction of heat from the outside to cylindrical container 13 via refrigerant injection tube 12. The angle θ between the orientation direction of the fibers and the extension direction of axial core CL of refrigerant injection tube 12 is 50 to 89°. From the viewpoints of slowing down the conduction of heat in refrigerant injection tube 12 and increasing rigidity, angle θ is more preferably 55 to 70°.

[0038] The resin to be impregnated into the substrate 21 is composed of, for example, an epoxy-based resin composition mainly made of epoxy resin, a phenol-based resin composition mainly made of phenol resin, or a polyimide-based resin composition mainly made of thermosetting polyimide resin.

[0039] From the viewpoint of slowing down the conduction of heat to cylindrical container 13, the amount of resin impregnated into base material 21 is preferably 15 to 50 wt % with respect to the total weight of the FRP constituting refrigerant injection tube 12.

[0040] Hereinafter, the proportion of resin impregnated into the base material will be referred to as the resin amount (wt%). The resin amount (wt%) indicates the weight of the resin component contained in the FRP as a percentage of the total weight of the FRP. The resin amount (wt%) is expressed as follows: Resin amount (wt%) = (resin weight (wt) x 100) / (fiber weight (wt) + resin weight (wt)). Note that "resin weight" refers to the weight of the resin converted into solid content. The resin weight converted into solid content refers to the weight of the resin excluding volatile components such as solvents.

[0041] [Cylindrical container 13] The cylindrical container 13 is a cylindrical container with a bottom having a storage section 23 for storing the refrigerant 16 therein. The storage section 23 is formed inside the cylindrical container 13. The cylindrical section 132 constituting the cylindrical container 13 may be configured in a shape such as a cylindrical shape, an elliptical cylindrical shape, or a square cylindrical shape.

[0042] The thickness of the wall constituting the cylindrical container 13 is preferably 2 to 30 mm, more preferably 2.5 to 15 mm, from the viewpoint of improving the heat insulation property and exhibiting rigidity in the cryogenic temperature range. Here, the thickness of the wall constituting the cylindrical container 13 refers to the thickness of the wall constituting the cylindrical portion 132.

[0043] When used in a device for measuring the magnetic field of the human body, for example, the size of cylindrical container 13 is preferably a size capable of storing 50 to 150 liters of refrigerant from the viewpoint of operating the device for a long period of time.

[0044] The cylindrical portion 132 constituting the cylindrical container 13 is made of FRP in which a base material is impregnated with resin. The base material constituting the FRP is made of, for example, fibers, fabric, a unidirectional fiber sheet in which multiple fibers are aligned in one direction, etc. In order to improve the heat insulation of the cylindrical container 13, it is preferable that the base material contains fibers or a unidirectional fiber sheet. In addition, in order to increase the rigidity of the cylindrical portion 132, it is more preferable that the base material has a configuration in which a fabric and a unidirectional fiber sheet are laminated.

[0045] i) When the base material is made of fibers, the type of fiber is at least one selected from the group consisting of glass fibers, alumina fibers, and carbon fibers. The type of fiber is preferably alumina fibers from the viewpoint of reducing thermal conductivity in the cryogenic temperature range. The base material may be made of multiple types of fibers, for example, alumina fibers and glass fibers. The fibers are wound in a spiral shape with respect to the extension direction of the axis of the cylindrical portion 132. The angle at which the fibers are wound with respect to the extension direction of the axis of the cylindrical portion 132 is 50 to 89 degrees.

[0046] ii) When the base material is made of a woven fabric, the woven fabric is made of at least one fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber. Examples of the weaving method of the woven fabric include satin weave, plain weave, and twill weave. The woven fabric is layered to form a tube. The woven fabric is layered, for example, so that the warp threads are at +45° and the weft threads are at -45° with respect to the extension direction of the axial core of the tubular part 132. The woven fabric may also be layered so that the warp threads are at 0° and the weft threads are at 90° with respect to the extension direction of the axial core of the tubular part 132. In addition, from the viewpoint of expressing pseudo-isotropic rigidity, for example, one woven fabric may be arranged so that the warp threads are at +45° and the weft threads are at -45° with respect to the extension direction of the axial core of the tubular part 132, and another woven fabric may be layered thereon so that the warp threads are at 0° and the weft threads are at 90°, and this layering may be repeated. The angle that the warp and weft make with respect to the extending direction of the axis of the tubular portion 132 is not strictly required, and an error in the angle is permitted that does not impair the rigidity of the tubular portion 132. The allowable range of this angle is, for example, ±10° with respect to the predetermined angle, and preferably ±5°.

[0047] iii) When the substrate is made of a unidirectional fiber sheet, the unidirectional fiber sheet is made of at least one selected from the group consisting of glass fiber, alumina fiber, and carbon fiber. FIG. 5 is a front view of the unidirectional fiber sheet. As shown in the figure, the unidirectional fiber sheet is made by arranging a plurality of flat yarns 66 in one direction. The unidirectional fiber sheet is held by a stopper thread 65 so that the aligned flat yarns 66 do not collapse. The unidirectional fiber sheet is wound in a spiral shape to form a tube, for example, as shown in FIG. 6, so that the angle φ between the fibers of the flat yarns 66 and the extension direction of the axis CL of the tube-shaped portion 132 is 50 to 89 degrees.

[0048] The resin impregnated into the base material constituting the cylindrical container 13 is composed of, for example, an epoxy-based resin composition mainly made of an epoxy resin, a phenol-based resin composition mainly made of a phenol resin, a polyimide-based resin composition mainly made of a thermosetting polyimide resin, etc. From the viewpoint of allowing the cylindrical container 13 to exhibit rigidity and toughness in the range from room temperature to extremely low temperature, and from the viewpoint of ensuring good processability, the resin is preferably an epoxy-based resin composition. The resin may be composed of two or more kinds of resin compositions.

[0049] The amount of resin in the cylindrical container 13 is preferably 15 to 50 wt % with respect to the total weight of the FRP constituting the cylindrical container 13, from the viewpoint of maintaining the rigidity of the cylindrical container 13 when the refrigerant 16 is stored therein.

[0050] The top surface portion 131 and the bottom surface portion 133 of the cylindrical container 13 are made of FRP in which a base material is impregnated with a resin. The base material is, for example, a woven fabric. A plurality of woven fabrics are laminated. The resin is preferably the same as that used to make the cylindrical portion 132 and the refrigerant injection tube 12, from the viewpoint of making the expansion and contraction behavior of the cylindrical portion 132 and the refrigerant injection tube 12 the same as that of the top surface portion 131 and the bottom surface portion 133 in the normal temperature and cryogenic temperature ranges. The amount of resin in the top surface portion 131 is preferably 15 to 50 wt % with respect to the total weight of the FRP used to make the top surface portion 131. The amount of resin in the bottom surface portion 133 is preferably 15 to 50 wt % with respect to the total weight of the FRP used to make the bottom surface portion 133. The thickness of the top surface portion 131 and the bottom surface portion 133 is, for example, the same as that of the cylindrical portion 132.

[0051] Examples of the coolant 16 include liquid oxygen, liquid nitrogen, liquid helium, etc. In applications for measuring the magnetic field of the spinal cord, liquid helium is preferred.

[0052] [Second cylindrical container 22] The second cylindrical container 22 includes a cylindrical portion 122 constituting the side wall thereof, and a bottom portion 123 closing one end of the cylindrical portion 122. The second cylindrical container 22 is fixed to a cylindrical portion 132 of the cylindrical container 13. The storage portion 24 is formed inside the second cylindrical container 22. The storage portion 24 is in communication with the storage portion 23 of the cylindrical container 13.

[0053] The second cylindrical container 22 is airtightly fixed to the cylindrical portion 132 such that the longitudinal direction of the second cylindrical container 22 is perpendicular to the longitudinal direction of the cylindrical portion 132 .

[0054] The second cylindrical container 22 is configured, for example, in a cylindrical shape, an elliptical cylindrical shape, a rectangular cylindrical shape, etc. The rectangular cylindrical shape includes a columnar shape whose cross section in a plane perpendicular to the longitudinal direction of the second cylindrical container 22 is a square, trapezoid, or rectangular shape.

[0055] The thickness of the wall constituting the cylindrical portion 122 of the second cylindrical container 22 may be the same as the thickness of the wall constituting the cylindrical container 13. When the insulating container 10 is used in a device for measuring the magnetic field of the spinal cord, the thickness of the wall constituting the second cylindrical container 22 is preferably 2 to 15 mm, more preferably 2.5 to 10 mm, from the viewpoint of shortening the lift-off and improving the thermal insulation. Here, the lift-off refers to the distance from the measurement surface of the superconducting quantum interference meter to the measurement site of the spinal cord.

[0056] The size of the second cylindrical container 22 is preferably such that, for example, when the insulated container 10 is used in a device for measuring the magnetic field of the spinal cord, the second cylindrical container 22 alone is large enough to store 10 to 30 liters of refrigerant 16.

[0057] Cylindrical portion 122 is located between the measurement object and the measurement device, and has a predetermined area facing them. First, the structure (basic structure) of the area other than the predetermined area of ​​cylindrical portion 122 will be described.

[0058] The cylindrical portion 122 has a cylindrical shape and is made of FRP made of a base material and a resin impregnated in the base material. The base material is made of i) a woven fabric, ii) a unidirectional fiber sheet, or iii) a woven fabric and a unidirectional fiber sheet. From the viewpoint of suppressing deformation of the cylindrical portion 122, it is preferable that the base material is made of ii) a unidirectional fiber sheet, or iii) a woven fabric and a unidirectional fiber sheet.

[0059] i) When the substrate is made of a woven fabric, the woven fabric is made of at least one type of fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber. From the viewpoint of maintaining the rigidity of the tubular portion 122 and ensuring good processability, the fiber is preferably glass fiber or alumina fiber. The substrate may be made of two or more types of fiber. Examples of the weaving method of the woven fabric include satin weave, plain weave, and twill weave. From the viewpoint of shaping ability, the weaving method of the woven fabric is preferably satin weave.

[0060] The woven fabrics are layered, for example, so that the warp threads are at 0° and the weft threads are at 90° with respect to the extension direction of the axial core of the tubular portion 122. The woven fabrics may be layered so that the warp threads are at +45° and the weft threads are at -45°. In addition, from the viewpoint of realizing pseudo-isotropic rigidity, the woven fabrics may be arranged so that the warp threads are at 0° and the weft threads are at 90° with respect to the extension direction of the axial core of the tubular portion 122, and another woven fabric may be layered on top of the first woven fabric so that the warp threads are at +45° and the weft threads are at -45°.

[0061] ii) When the substrate is made of a unidirectional fiber sheet, the unidirectional fiber sheet is made of at least one type selected from the group consisting of glass fiber, alumina fiber, and carbon fiber. From the viewpoint of maintaining the rigidity of the tubular portion 122 and ensuring good processability, this fiber is preferably glass fiber or alumina fiber. The substrate may be made of two or more types of fiber. From the viewpoint of suppressing deformation of the tubular portion 122, the unidirectional fiber sheet is preferably laminated so that the fibers of the unidirectional fiber sheet are perpendicular (90°) to the extension direction of the axis of the tubular portion 122.

[0062] iii) When the base material is composed of a woven fabric and a unidirectional fiber sheet, the base material has a structure in which the woven fabric is laminated on at least one side of the unidirectional fiber sheet, a structure in which the unidirectional fiber sheet is laminated on both sides of the woven fabric, or a structure in which the woven fabric and the unidirectional fiber sheet are alternately laminated, from the viewpoint of suppressing deformation of the tubular portion 122. From the viewpoint of increasing rigidity, the woven fabric and the unidirectional fiber sheet are preferably configured to be line-symmetrical with respect to the woven fabric or unidirectional fiber sheet that is at the center in the thickness direction when the cross section of the wall of the tubular portion 122 is viewed. For example, the woven fabric and the unidirectional fiber sheet are preferably configured to have a structure in which the woven fabric is laminated on both sides of the unidirectional fiber sheet with the unidirectional fiber sheet at the center. In this case, the unidirectional fiber sheet is preferably laminated so that the fibers of the unidirectional fiber sheet are perpendicular (90°) to the extension direction of the axis of the tubular portion 122, from the viewpoint of suppressing deformation of the tubular portion 122. Note that the perpendicular does not have a strict meaning, and an error is allowed to the extent that the rigidity of the tubular portion 122 is not impaired. The tolerance for this angle is, for example, 90°±15°.

[0063] Next, the structure of the predetermined region of the cylindrical portion 122 will be described with reference to FIG. 8. FIG. 8 is a cross-sectional view of the thermally insulated container 10 shown in FIG. 2 taken along the line BB. The "predetermined region" refers to a region located between the measurement object 101 and the measurement device 102 during the use of the thermally insulated container 10, where a thin wall is desired to be formed in order to reduce lift-off. The predetermined region of the cylindrical portion 122 is the region indicated by reference numeral 111 in FIG. 8, and may be a partial region of the upper wall or the entire region of the upper wall. The "predetermined region" of the outer container 14 will be described later.

[0064] The predetermined region 111 is made of FRP. The substrate of the FRP is either i) a woven fabric or ii) a woven fabric and a unidirectional fiber sheet.

[0065] i) When the substrate is made of a woven fabric, the structure of the substrate in the predetermined region 111 is substantially the same as the structure when the substrate other than the predetermined region 111 is made of a woven fabric. That is, the substrate is made of at least one type of fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber. From the viewpoint of maintaining the rigidity of the tubular portion 122 and ensuring good processability, the fiber is preferably glass fiber or alumina fiber. The substrate may be made of two or more types of fiber. Examples of the weaving method of the substrate include satin weave, plain weave, and twill weave. From the viewpoint of shaping property, the weaving method of the substrate is preferably satin weave.

[0066] On the other hand, ii) when the base material in the predetermined region 111 is composed of a woven fabric and a unidirectional fiber sheet, the structure is substantially the same as when the base material other than the predetermined region 111 is composed of a woven fabric and a unidirectional fiber sheet. That is, from the viewpoint of suppressing deformation of the tubular portion 122, the base material has a configuration in which a woven fabric is laminated on at least one side of a unidirectional fiber sheet, a configuration in which unidirectional fiber sheets are laminated on both sides of a woven fabric, or a configuration in which a woven fabric and a unidirectional fiber sheet are alternately laminated.

[0067] When the base material of the predetermined region 111 includes a unidirectional fiber sheet, the base material is preferably configured to be symmetrical with respect to the woven fabric or unidirectional fiber sheet located at the center in the thickness direction when the cross section of the wall of the tubular portion 122 is viewed, from the viewpoint of increasing rigidity. For example, the woven fabric and the unidirectional fiber sheet are preferably configured such that the woven fabric is laminated on both sides of the unidirectional fiber sheet with the unidirectional fiber sheet at the center. In this case, the unidirectional fiber sheet is preferably laminated so that the fibers of the unidirectional fiber sheet are perpendicular (90°) to the extension direction of the axial core of the tubular portion 122, from the viewpoint of suppressing deformation of the tubular portion 122. Note that the perpendicularity is not in the strict sense, and an error is allowed to the extent that the rigidity of the tubular portion 122 is not impaired. The allowable range of this angle is, for example, 90°±15°.

[0068] When the base material of the predetermined region 111 includes a unidirectional fiber sheet, the unidirectional fiber sheet exhibits high rigidity against stress, and thus the FRP has high rigidity. Therefore, compared to a case where the base material is made of a woven fabric, the wall can be formed relatively thin while ensuring high rigidity. This allows the measuring device 102 to be brought closer to the measurement target 101, for example, when the insulated container 10 is in use. From the viewpoint of maintaining rigidity, the predetermined region 111 is preferably the entire region of the upper wall of the tubular portion 122.

[0069] When the tubular portion 122 has a cylindrical shape, the predetermined region 111 of the tubular portion 122 is a partial region of the circumferential surface (curved surface) of a semicylinder that constitutes half of the cylinder, or the entire region of the circumferential surface (curved surface) of the semicylinder.

[0070] The amount of resin in the predetermined region 111 of the tubular portion 122 and other than the predetermined region 111 is 15 to 50 wt % with respect to the total weight of the FRP constituting the tubular portion 122, from the viewpoint of maintaining rigidity.

[0071] The resin impregnated into the base material constituting the cylindrical portion 122 is composed of, for example, an epoxy resin composition mainly made of an epoxy resin, a phenol resin composition mainly made of a phenol resin, or a polyimide resin composition mainly made of a thermosetting polyimide resin. From the viewpoint of having rigidity and toughness at room temperature and at extremely low temperatures and from the viewpoint of ensuring good processability, the resin is preferably an epoxy resin composition. The resin may be composed of two or more kinds of resin compositions.

[0072] The bottom portion 123 is made of FRP composed of a base material and a resin impregnated in the base material. The base material is made of a woven fabric in which multiple layers are laminated. From the viewpoint of making the expansion and contraction behavior of the cylindrical portion 122 and the bottom portion 123 the same in the normal temperature to cryogenic temperature range, it is preferable that the resin is the same as the resin constituting the cylindrical portion 122. From the viewpoint of maintaining the rigidity of the cylindrical container 13 when storing the refrigerant, the amount of resin in the bottom portion 123 is preferably 15 to 50 wt % with respect to the total weight of the FRP of the bottom portion 123, which is the same as the amount of resin in the cylindrical portion 122.

[0073] The storage section 23 of the cylindrical container 13 and the storage section 24 of the second cylindrical container 22 may be fixed in communication with each other via a member such as a tube. In this case, the member for communicating between the storage section 23 and the storage section 24 is preferably made of the same material as the material constituting the cylindrical container 13 and the second cylindrical container 22.

[0074] Examples of a method for joining the cylindrical container 13 and the second cylindrical container 22 include a method of applying an adhesive to the joining surfaces of the cylindrical container 13 and the second cylindrical container 22 to form an airtight joining, and a method of forming threads on the joining surfaces of the cylindrical container 13 and the second cylindrical container 22, applying an adhesive, and then screwing them together to form an airtight joining. The joining method is preferably an airtight joining method that can maintain the gap 15 in a vacuum state.

[0075] From the viewpoint of exhibiting good adhesiveness, the adhesive used is preferably the same resin as that constituting the refrigerant injection tube 12 and the cylindrical container 13. Examples of the resin include an epoxy resin composition mainly made of an epoxy resin, a phenol resin composition mainly made of a phenol resin, or a polyimide resin composition mainly made of a thermosetting polyimide resin. From the viewpoint of having rigidity and toughness in the range from room temperature to extremely low temperature, and from the viewpoint of ensuring good adhesiveness, the resin is preferably an epoxy resin composition. The resin may be composed of two or more kinds of resin compositions.

[0076] [Outer container 14] As shown in Fig. 3, the outer container 14 is configured to surround the inner container 11 with a gap 15 therebetween. The upper surface of the outer container 14 supports the cylindrical container 13 via the refrigerant injection tube 12. In the insulated container 10, the end face of the refrigerant injection tube 12 and the upper surface of the outer container 14 are on the same plane.

[0077] Here, "surrounding" refers to a state in which the outer container 14 encloses the inner container 11 via the gap 15. The "inside" of the outer container 14 refers to the area of ​​the outer container 14 that contacts the gap 15. The part that becomes the top surface of the outer container 14 is referred to as the "upper surface portion."

[0078] From the viewpoint of increasing the heat insulating effect, it is preferable that the gap 15 is in a vacuum state. The outer container 14 has a rigidity sufficient to maintain the shape of the outer container 14 even when the gap 15 is in a vacuum state.

[0079] The shape and size of the outer container 14 are not limited as long as they can surround the inner container 11. From the viewpoint of preventing deformation of the container when the gap 15 is made into a vacuum state, the outer container 14 is preferably configured with a rounded shape capable of dispersing stress. In particular, it is preferable that the corners of the outer container 14 are formed with a shape having a large radius of curvature. This makes it possible to prevent the shrinkage stress on the container caused by the vacuum from concentrating on a specific part of the container.

[0080] The outer container 14 will also be described by dividing it into a predetermined area 112 located between the measurement object 101 and the measurement device 102 shown in Fig. 8 and the other areas. First, the configuration of the areas other than the predetermined area 112 will be described.

[0081] The thickness of the wall constituting the outer container 14 is preferably equal to or greater than the thickness of the cylindrical container 13 and the second cylindrical container 22, from the viewpoint of preventing deformation of the container when the gap 15 is made into a vacuum state.

[0082] The portion of the outer container 14 other than the predetermined region 112 is made of FRP composed of a base material and a resin impregnated in the base material. The base material constituting the predetermined region 112 of the outer container 14 may be made of i) a woven fabric, or ii) a woven fabric and a unidirectional fiber sheet.

[0083] When the substrate is made of a woven fabric, the woven fabric is made of at least one type of fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber. The fibers constituting the woven fabric are preferably glass fiber and alumina fiber from the viewpoint of maintaining rigidity and ensuring good processability. The substrate may be made of two or more types of fibers. Examples of the weaving method of the woven fabric include satin weave, plain weave, and twill weave. From the viewpoint of shape imparting, the weaving method of the woven fabric is preferably satin weave.

[0084] The woven fabrics may be laminated, for example, so that the warp threads of the woven fabric are at 0° and the weft threads are at 90° with respect to the extending direction of the axial core of the second cylindrical container 22, or so that the warp threads are at +45° and the weft threads are at -45°. From the viewpoint of exhibiting quasi-isotropic rigidity, one woven fabric may be arranged so that the warp threads are at 0° and the weft threads are at 90° with respect to the extending direction of the axial core of the second cylindrical container 22, and another woven fabric may be laminated on the first woven fabric so that the warp threads are at +45° and the weft threads are at -45°. Here, the allowable range of the angle formed by the warp threads and the weft threads with respect to the extending direction of the axial core of the second cylindrical container 22 is ±10°, preferably ±5°.

[0085] The resin constituting the region other than the predetermined region 112 of the outer container 14 is composed of, for example, an epoxy resin composition mainly made of an epoxy resin, a phenol resin composition mainly made of a phenol resin, or a polyimide resin composition mainly made of a thermosetting polyimide resin. From the viewpoint of having rigidity and toughness in the range from room temperature to extremely low temperature, and from the viewpoint of ensuring good processability, the resin is preferably an epoxy resin composition. The resin may be composed of two or more kinds of resin compositions.

[0086] Next, the structure of the predetermined region 112 of the outer container 14 will be described with reference to circle 2 in Fig. 8. The predetermined region 112 of the outer container 14 is also made of FRP. The base material constituting the predetermined region 112 of the outer container 14 is made of i) a woven fabric, or ii) a woven fabric and a unidirectional fiber sheet.

[0087] i) When the substrate is made of a woven fabric, its structure is the same as that of the substrate of the other part of the outer container 14. That is, the woven fabric is made of at least one type of fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber. From the viewpoint of maintaining rigidity and ensuring good processability, the fibers constituting the woven fabric are preferably glass fiber and alumina fiber. The substrate may be made of two or more types of fibers. Examples of the weaving method of the woven fabric include satin weave, plain weave, and twill weave. From the viewpoint of shape imparting, the weaving method of the woven fabric is preferably satin weave.

[0088] ii) Next, when the substrate is composed of a woven fabric and a unidirectional fiber sheet, the woven fabric is substantially the same as the woven fabric constituting the substrate of the other part of the outer container 14. The unidirectional fiber sheet is composed of at least one type of fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber. From the viewpoints of maintaining rigidity and ensuring good processability, this fiber is preferably glass fiber or alumina fiber. This fiber may be composed of two or more types of fibers.

[0089] From the viewpoints of increasing the rigidity and suppressing deformation of the outer container 14, the unidirectional fiber sheet is preferably laminated so that the fibers constituting the unidirectional fiber sheet are parallel (0°) to the extending direction of the axial core of the second cylindrical container 22 (cylindrical portion 122). Here, the parallel (0°) allows for an error that does not decrease the rigidity of the outer container 14. The allowable range of the angle is ±10°, and preferably ±5°.

[0090] The load of the measurement object 101 is applied to the predetermined region 112 of the outer container 14, and the predetermined region 112 is required to have higher rigidity than other portions. For this reason, as shown in an enlarged view in the circle 2 of FIG. 8, the outer container 14 further includes a honeycomb sheet 70, which is strong against shear force and contributes to heat insulation, in the FRP constituting the predetermined region 112. The honeycomb sheet 70 is composed of, for example, an aramid honeycomb sheet, a paper honeycomb sheet, or a non-combustible honeycomb sheet. From the viewpoint of ensuring rigidity, the honeycomb sheet 70 is preferably an aramid honeycomb sheet. The size of the polygonal, for example, hexagonal, cells constituting the honeycomb sheet 70 is 3 to 10 mm in length of one side, and is preferably 3 to 5 mm, from the viewpoint of maintaining heat insulation and maintaining the honeycomb shape. The thickness (height) of the honeycomb sheet is 1 to 7 mm, and is preferably 1 to 3 mm, from the viewpoint of maintaining heat insulation and making the wall of the outer container 14 thin. The inside of the cell is void, and heat insulation is enhanced. The cell cavity may be a vacuum or may be filled with air.

[0091] When the base material of the predetermined region 112 is made of a woven fabric, the woven fabric is laminated on both sides of the honeycomb sheet 70. On the other hand, when the base material of the predetermined region 112 is made of a woven fabric and a unidirectional fiber sheet, it is desirable to laminate the unidirectional fiber sheet on at least one of the sides of the honeycomb sheet 70. For example, the FRP of the predetermined region 112 of the outer container 14 has a configuration in which i) woven fabric is laminated on both sides of the honeycomb sheet 70, and a unidirectional fiber sheet is laminated on at least one of the woven fabrics, ii) unidirectional fiber sheets are laminated on both sides of the honeycomb sheet 70, and woven fabrics are laminated on these unidirectional fiber sheets, or iii) a unidirectional fiber sheet is laminated on one side of the honeycomb sheet 70, a woven fabric is laminated on the unidirectional fiber sheet, and a woven fabric is laminated on the other side of the honeycomb sheet 70.

[0092] When the base material constituting the predetermined region 112 of the outer container 14 includes a woven fabric and a unidirectional fiber sheet, the predetermined region 112 has higher rigidity than when the base material is a woven fabric. This allows the wall constituting the predetermined region 112 of the outer container 14 to be made thinner. Furthermore, a configuration consisting of a woven fabric and a unidirectional fiber sheet is less likely to cause deformation of the predetermined region of the outer container 14 even if the wall is made thinner, compared to a configuration consisting of only a woven fabric.

[0093] The predetermined area 112 of the outer container 14 is preferably larger (wider) than the predetermined area 111 of the second cylindrical container 22, from the viewpoint of improving heat insulation and rigidity.

[0094] The resin constituting the predetermined region 112 of the outer container 14 may be the same as the resin constituting the region other than the predetermined region 112. That is, the resin is composed of, for example, an epoxy resin composition mainly made of an epoxy resin, a phenol resin composition mainly made of a phenol resin, or a polyimide resin composition mainly made of a thermosetting polyimide resin. From the viewpoint of having rigidity and toughness in the range from room temperature to extremely low temperature, and from the viewpoint of ensuring good processability, the resin is preferably an epoxy resin composition. The resin may be composed of two or more types of resin compositions.

[0095] The FRP base material in the portion other than the predetermined region 112 of the outer container 14 may be composed of a woven fabric and a unidirectional fiber sheet. In this case, from the viewpoint of suppressing deformation of the outer container 14, the woven fabric and the unidirectional fiber sheet have a configuration in which the woven fabric is laminated on at least one side of the unidirectional fiber sheet, a configuration in which the unidirectional fiber sheet is laminated on both sides of the woven fabric, or a configuration in which the woven fabric and the unidirectional fiber sheet are alternately laminated.

[0096] The amount of resin in the predetermined region 112 of the outer container 14 is preferably 15 to 50 wt % with respect to the total weight of the FRP constituting the outer container 14, from the viewpoint of maintaining the rigidity of the outer container 14 when the refrigerant 16 is stored therein.

[0097] A support (not shown) may be placed in the gap 15 to support the load and fix the cylindrical container 13 and the second cylindrical container 22 in fixed positions.

[0098] The outer container 14 and the refrigerant injection tube 12 are airtightly joined. Examples of methods for joining the outer container 14 and the refrigerant injection tube 12 include a method of applying an adhesive to the joint surfaces of the outer container 14 and the refrigerant injection tube 12 to form an airtight joint, and a method of forming threads on the joint surfaces of the outer container 14 and the refrigerant injection tube 12, applying an adhesive, and then screwing them together to form an airtight joint.

[0099] In the above embodiment, the cylindrical portion 132 is described as being composed of a single-layer wall, but the wall of the cylindrical portion 132 may be composed of a multi-layer wall. In addition, the refrigerant injection tube 12 and the like having a similar cylindrical shape may also be composed of a multi-layer wall. For example, as shown in circle 1 in FIG. 7, the cylindrical portion 132 may be composed of an outer layer 132O and an inner layer 132I. The outer layer 132O constitutes a layer close to the void 15 (outside), and the inner layer 132I constitutes a layer close to the refrigerant 16 (inside).

[0100] The outer layer 132O and the inner layer 132I are each made of FRP. The base material constituting the FRP is a fiber or a unidirectional fiber sheet. The material of the base material is glass or alumina.

[0101] From the viewpoints of ensuring the rigidity of the cylindrical portion 132, reducing the thermal conductivity of the cylindrical portion 132, and reducing costs, the base material constituting the outer layer 132O is preferably a fiber or a unidirectional fiber sheet. The material of the base material is preferably glass. The base material constituting the inner layer 132I is preferably a fiber or a unidirectional fiber sheet. The material of the base material is preferably alumina.

[0102] The base materials constituting the outer layer 132O and the inner layer 132I are each wound in a spiral shape with respect to the extension direction of the axial core of the tubular portion 132. The inclination of the fibers constituting the fibers or the unidirectional fiber sheet with respect to the extension direction of the axial core of the tubular portion 132 may be different or the same between the outer layer 132O and the inner layer 132I. From the viewpoint of increasing the rigidity of the tubular portion 132 and improving the workability (ease of demolding from a mold), it is preferable that the inclination of the fibers constituting the inner layer 132I or the fibers constituting the unidirectional fiber sheet is larger than the inclination of the fibers constituting the outer layer 132O or the fibers constituting the unidirectional fiber sheet. It is preferable that the thickness of the outer layer 132O and the inner layer 132I is the same or that the inner layer 132I is thicker than the outer layer 132O. The ratio of the thickness of the inner layer 132I to the thickness of the outer layer 132O is 50:50 to 80:20, preferably 50:50 to 70:30, and more preferably 50:50 to 60:40.

[0103] From the viewpoint of preventing delamination between layers, it is preferable that the resins impregnated into the base materials constituting the outer layer 132O and the inner layer 132I are the same resin.

[0104] When the FRP configuration of the cylindrical portion 132 is a two-layer configuration, it is preferable that the FRP configuration of the top surface portion 131 and the bottom surface portion 133 is also a two-layer configuration. From the viewpoint of slowing down the conduction of heat from the outside to the entire inner container 11 via the refrigerant injection tube 12, the material of the fibers configuring the outer layer of the top surface portion 131 and the bottom surface portion 133 is, for example, glass, and the material of the fibers configuring the inner layer is, for example, alumina. The resin configuring the top surface portion 131 and the bottom surface portion 133 is preferably the same resin as the resin configuring the cylindrical portion 132.

[0105] Hereinafter, the methods for manufacturing the refrigerant injection tube 12, the cylindrical container 13, the second cylindrical container 22, and the outer container 14 will be described.

[0106] [Method of manufacturing the refrigerant injection tube 12] The manufacturing method for refrigerant injection tube 12 includes a molding step in which a fiber impregnated with liquid resin, i.e., a base material, is spirally wound around a rod-shaped mold to form the shape of refrigerant injection tube 12, a hardening step in which the resin is hardened by heating, and a demolding step in which the hardened refrigerant injection tube 12 is removed from the mold.

[0107] The molding method in the molding step may be, for example, a filament winding method, in which the fiber is wound around the mold at an angle of 50 to 89° with respect to the extension direction of the axis of the mold.

[0108] In the curing step, the temperature and time for curing the resin can be appropriately set depending on the type of resin, the amount of resin, etc. For example, when an epoxy resin composition is used as the resin and the amount of resin is 20 to 50 wt%, the heating temperature is 80 to 150° C. and the curing time is 1 to 12 hours.

[0109] In the demolding step, the mold is cooled to room temperature, and refrigerant injection tube 12 is removed from the mold, thereby obtaining refrigerant injection tube 12.

[0110] [Method of manufacturing the cylindrical container 13] An example of a manufacturing method of the cylindrical container 13 will be described. The cylindrical portion 132 constituting the cylindrical container 13 is obtained by winding prepreg, which is a base material composed of fibers, woven fabric, unidirectional fiber sheet, etc., impregnated with resin, around a rod-shaped mold while taking into consideration the direction of the fibers, curing, and cutting into a predetermined shape. The top surface portion 131 and bottom surface portion 133 constituting the cylindrical container 13 are obtained by stacking prepreg, curing, and cutting into a predetermined shape. Here, the prepreg refers to a composite material in a B-stage state in which the resin curing reaction has progressed partway but not completely.

[0111] Next, the formed top surface portion 131 and the cylindrical portion 132 are airtightly joined. Examples of the joining method include a method of joining the joining surface of the top surface portion 131 and the cylindrical portion 132 with an adhesive or the like, and a method of forming threads on the joining surfaces of the top surface portion 131 and the cylindrical portion 132 and screwing them together. An adhesive or the like that hardens at room temperature may be applied to the threads before screwing them together. This allows the joining surfaces to be sealed airtight. The bottom surface portion 133 and the cylindrical portion 132 can also be joined by the same method as the joining method of the top surface portion 131 and the cylindrical portion 132. In this manner, the cylindrical container 13 is completed.

[0112] Another example of the manufacturing method for the cylindrical container 13 will be described below. This manufacturing method includes a prepreg preparation step of impregnating a base material with resin and then heating it to prepare a prepreg, a molding step of attaching the prepreg to the surface of a mold having the shape of the cylindrical container 13 and molding it, a curing step of curing the prepreg by applying heat and pressure, and a demolding step of removing the cured prepreg from the mold.

[0113] In the prepreg production process, the time for impregnating the base material with the resin and the temperature for heating the fabric after impregnation are appropriately set depending on the type of resin and the amount of resin (amount of resin) attached to the fabric, etc. For example, when the resin is an epoxy resin composition and the amount of resin is 20 to 50 wt%, the time is 1 to 12 hours and the temperature is 80 to 150°C.

[0114] In the molding process, the prepreg is cut to fit the shape of the cylindrical container 13. The prepreg is attached to a mold and molded. If the mold has a complex shape, the prepreg is cut into small pieces and attached to the mold and molded. This allows the prepreg to follow the shape of the mold.

[0115] In the curing step, the prepreg is cured by heating and pressurization. For example, the curing method may be an autoclave molding method using a high-pressure cooker. This allows the prepreg to be cured uniformly.

[0116] In the demolding step, the prepreg is cooled to room temperature and removed from the mold, and a cylindrical container 13 is obtained.

[0117] Furthermore, for example, when the tubular portion 132 is an FRP having two layers of walls, the tubular portion 132 can be produced by, for example, a filament winding method.

[0118] When the base material constituting the inner layer is alumina fiber and the base material constituting the outer layer is glass fiber, the cylindrical portion 132 is produced as follows. Alumina fiber impregnated with resin is wound in a spiral shape around a rod-shaped die. Next, glass fiber impregnated with resin is wound in a spiral shape around the wound alumina fiber to form the cylindrical portion 132 composed of two layers of walls. After that, the resin constituting the cylindrical portion 132 is hardened by heating. After cooling to room temperature, the cylindrical portion 132 is removed from the die to obtain the cylindrical portion 132 composed of two layers of walls.

[0119] The top surface portion 131 and the bottom surface portion 133 are also produced so as to have two-layer walls. The manufacturing method of the top surface portion 131 includes a prepreg manufacturing process for manufacturing a prepreg having a woven fabric of alumina fiber as a base material and a prepreg having a woven fabric of glass fiber as a base material, a lamination process for laminating the two types of prepregs so as to form two-layer walls, and a curing process for curing the laminated prepregs. The bottom surface portion 133 is manufactured by the same manufacturing method as the manufacturing method of the top surface portion 131.

[0120] The method for joining the upper surface portion 131, which is composed of two layers of walls, to the tubular portion 132, and the method for joining the bottom surface portion 133, which is also composed of two layers of walls, to the tubular portion 132 can be the same as the method for joining the upper surface portion 131 to the tubular portion 132.

[0121] [Method of manufacturing the second cylindrical container 22] The second cylindrical container 22 is prepared by separately preparing the cylindrical portion 122 and the bottom portion 123 which constitute the second cylindrical container 22 .

[0122] First, a method for manufacturing the tubular portion 122 whose base material is made of a woven fabric will be described. The method for manufacturing the tubular portion 122 includes a cross prepreg preparation step of preparing a cross prepreg using a woven fabric as the base material, a cross prepreg molding step of attaching and molding the cross prepreg to the surface of a mold for forming the tubular portion 122 such that the extension direction of the warp or weft is perpendicular to the extension direction of the axial core of the mold, a curing step of curing the laminated cross prepreg, and a demolding step of removing the cured cross prepreg from the mold.

[0123] In the cross prepreg manufacturing process, the woven fabric is impregnated with resin. The woven fabric is then heated. The heating time and heating temperature are appropriately set depending on the type of resin and the amount of resin (resin amount) attached to the woven fabric. For example, when the resin is an epoxy resin composition and the resin amount is 20 to 50 wt%, the heating time is 1 to 12 hours and the heating temperature is 80 to 150°C.

[0124] In the cross prepreg molding process, the cross prepreg is cut to fit the size of a mold. The cross prepreg is attached to the mold and molded. For example, the cross prepreg is attached and molded so that the warp or weft yarns constituting the woven fabric are perpendicular to the extension direction of the axis of the mold.

[0125] In the curing step, the cross prepreg is cured by heating and pressurization. For example, the curing method may be an autoclave molding method using a high-pressure cooker. This allows the cross prepreg to be cured uniformly.

[0126] In the demolding step, the cross prepreg is cooled to room temperature and removed from the mold, and the cylindrical portion 122 is obtained.

[0127] Next, the bottom portion 123 is produced by the same production method as the bottom portion 133. The produced bottom portion 123 is joined to the cylindrical portion 122 to obtain the second cylindrical container 22. The method for joining the bottom portion 123 and the cylindrical portion 122 can be the same as the method for joining the bottom portion 133 and the cylindrical portion 132.

[0128] Next, a manufacturing method of the cylindrical part 122 whose base material is composed of a woven fabric and a unidirectional fiber sheet will be described. The manufacturing method of the cylindrical part 122 whose base material is composed of a woven fabric and a unidirectional fiber sheet includes a prepreg manufacturing step of manufacturing a cross prepreg using a woven fabric as a base material and a UD prepreg using a unidirectional fiber sheet as a base material, a cross prepreg first molding step of pasting the cross prepreg on the surface of a mold for forming the cylindrical part 122 so that the extension direction of the warp or weft of the woven fabric is perpendicular to the extension direction of the axial core of the mold, a UD prepreg molding step of pasting the UD prepreg on the cross prepreg so that the fibers of the unidirectional fiber sheet are perpendicular to the extension direction of the axial core of the mold, a cross prepreg second molding step of pasting the cross prepreg on the UD prepreg so that the extension direction of the warp or weft of the woven fabric is perpendicular to the extension direction of the axial core of the mold, a curing step of curing the laminated prepregs, and a demolding step of removing the cured prepreg from the mold.

[0129] In the prepreg production process, the woven fabric is impregnated with resin, and the unidirectional fiber sheet is impregnated with resin. Then, the woven fabric and the unidirectional fiber sheet are heated. The heating time and heating temperature are appropriately set depending on the type of resin and the amount of resin (resin amount) attached to the woven fabric and the unidirectional fiber sheet. For example, when the resin is an epoxy resin composition and the resin amount is 20 to 50 wt%, the heating time is 1 to 12 hours and the heating temperature is 80 to 150°C.

[0130] In the first cross prepreg molding process, the cross prepreg is cut to fit the size of the mold. The cross prepreg is attached to the mold and molded. The cross prepreg is attached and molded so that the warp or weft yarns constituting the fabric are perpendicular to the extension direction of the axis of the mold.

[0131] In the UD prepreg molding process, the UD prepreg is attached onto the cross prepreg and molded so that the fibers of the unidirectional fiber sheet are perpendicular to the extension direction of the axial core of the mold. The region where the UD prepreg is attached onto the cross prepreg and molded may be at least the predetermined region 111 in the cylindrical portion 122. From the viewpoint of increasing the rigidity of the cylindrical portion 122 and from the viewpoint of suppressing deformation of the cylindrical portion 122, it is preferable that the UD prepreg is attached onto the entire region on the cross prepreg and molded.

[0132] In the second cross prepreg molding process, the cross prepreg is cut to fit the size of the mold. The cross prepreg is then attached to the UD prepreg and molded. The cross prepreg is then attached so that the warp or weft of the fabric is perpendicular to the extension direction of the axis of the mold.

[0133] In the curing step, the prepreg is cured by heating and pressurization. For example, the curing method may be an autoclave molding method using a high-pressure cooker. This allows the prepreg to be cured uniformly.

[0134] In the demolding process, the prepreg is cooled to room temperature and removed from the mold, and the cylindrical portion 122 is obtained.

[0135] The manufacturing method for the tubular portion 122 whose base material is a unidirectional fiber sheet is the same as the manufacturing method for the tubular portion 122 whose base material is a woven fabric and a unidirectional fiber sheet described above, except for the process relating to the woven fabric.

[0136] In the case where the configuration of the specified region 111 of the tubular portion 122 differs from that of other regions, a manufacturing method that can obtain the desired configuration can be adopted for the specified region 111, and for the other regions, a combination of manufacturing methods that can obtain the desired configuration to the extent possible can be adopted.

[0137] [Method of manufacturing outer container 14] The outer container 14 is produced by dividing it into a first portion surrounding the cylindrical container 13, a second portion surrounding the second cylindrical container 22, and a third portion surrounding the bottom portion 123.

[0138] First, an example of a method for manufacturing the first part will be described. When the FRP base material is composed of a woven fabric, the method for manufacturing the first part includes a cross prepreg preparation step of preparing a cross prepreg using the woven fabric as the base material, a cross prepreg molding step of attaching and molding the cross prepreg onto the surface of a mold shaped to form an outer container 14 surrounding a cylindrical container 13, a curing step of curing the laminated cross prepreg by applying heat and pressure, and a demolding step of removing the cured cross prepreg from the mold.

[0139] In the cross prepreg manufacturing process, a woven fabric as a base material is impregnated with a resin. The woven fabric is then heated. The heating time and heating temperature are appropriately set depending on the type of resin and the amount of resin (resin amount) attached to the woven fabric. For example, when the resin is an epoxy resin composition and the resin amount is 20 to 50 wt%, the heating time is 1 to 12 hours and the heating temperature is 80 to 150°C.

[0140] In the cross prepreg molding process, the cross prepreg is cut to fit the size of the mold. The cross prepreg is then attached to the mold and molded.

[0141] In the curing step, the cross prepreg is cured by heating and pressurization. For example, the curing method may be an autoclave molding method using a high-pressure cooker. This allows the cross prepreg to be cured uniformly.

[0142] In the demolding step, the cross prepreg is cooled to room temperature and removed from the mold, thus obtaining the first part.

[0143] Next, an example of a method for manufacturing the second part of the outer container 14 will be described. When the base material is composed of a woven fabric, a method for producing the second part includes a cross prepreg preparation step of preparing a cross prepreg using the woven fabric as the base material, a first cross prepreg molding step of attaching and molding the cross prepreg to the surface of a mold shaped to form the second part of the outer container 14 surrounding the second cylindrical container 22 such that the extension direction of the warp or weft of the woven fabric is parallel to the extension direction of the axial core of the mold, a honeycomb sheet lamination step of laminating a honeycomb sheet 70 on a predetermined region 112 of the attached and molded cross prepreg, a second cross prepreg molding step of attaching and molding a cross prepreg on the honeycomb sheet 70 and on the cross prepreg attached and molded in the first cross prepreg molding step such that the extension direction of the warp or weft of the woven fabric is parallel to the extension direction of the axial core of the mold, a curing step of curing the laminated cross prepreg, and a demolding step of removing the cured cross prepreg from the mold.

[0144] In the cross prepreg manufacturing process, a woven fabric as a base material is impregnated with a resin. The woven fabric is then heated. The heating time and heating temperature are appropriately set depending on the type of resin and the amount of resin (resin amount) attached to the woven fabric. For example, when the resin is an epoxy resin composition and the resin amount is 20 to 50 wt%, the heating time is 1 to 12 hours and the heating temperature is 80 to 150°C.

[0145] In the first cross prepreg molding step, the cross prepreg is cut to match the shape of the second portion of the outer container 14. The cross prepreg is attached to a mold and molded. The cross prepreg is attached and molded so that the warp or weft of the fabric is parallel to the extending direction of the axis of the mold. The cross prepreg may be attached and molded while being exposed to hot air of 50 to 100°C.

[0146] In the honeycomb sheet lamination step, the honeycomb sheet 70 is placed on the area that is to become the predetermined area 112 of the cross prepreg.

[0147] In the second cross prepreg molding process, the cross prepreg is further molded by being attached on the honeycomb sheet 70 and the cross prepreg that have already been attached, along the shape of a mold. The cross prepreg is attached and molded so that the warp or weft of the fabric is parallel to the extending direction of the axis of the mold. The cross prepreg may be attached and molded while being exposed to hot air of 50 to 100°C.

[0148] In the curing step, the laminated cross prepregs are cured by heating and pressurization. For example, the curing method may be an autoclave molding method using a high-pressure cooker. This allows the cross prepregs to be cured uniformly.

[0149] In the demolding step, the cloth prepreg is cooled to room temperature and removed from the mold, and the outer container 14 surrounding the second cylindrical container 22 is obtained.

[0150] Next, an example of a method for manufacturing the second part when the base material is composed of a woven fabric and a unidirectional fiber sheet will be described. This manufacturing method includes a prepreg manufacturing step of manufacturing a cross prepreg using a woven fabric as the base material and a UD prepreg using a unidirectional fiber sheet as the base material, a cross prepreg first molding step of attaching and molding the cross prepreg to the surface of a mold that has the shape of the second part of the outer container 14 surrounding the predetermined region 111 of the second cylindrical container 22 such that the extension direction of the warp or weft of the woven fabric is parallel to the extension direction of the axial core of the mold, a honeycomb sheet lamination step of laminating a honeycomb sheet on the predetermined region 112 of the cross prepreg, and a UD prepreg first molding step of laminating a honeycomb sheet on the predetermined region 112 of the cross prepreg. The method includes a cross prepreg second molding process in which cross prepregs are pasted and molded on top of the honeycomb sheet and on top of the cross prepreg pasted and molded in the cross prepreg first molding process so that the extension direction of the weft yarns is parallel to the extension direction of the axial core of the mold; a UD prepreg molding process in which a UD prepreg is pasted and molded on top of the cross prepreg so that the fibers of the unidirectional fiber sheet are parallel to the extension direction of the axial core of the mold; a curing process in which the stacked prepregs are cured; and a demolding process in which the cured prepregs are removed from the mold.

[0151] In the prepreg preparation process, the woven fabric and the unidirectional fiber sheet are impregnated with resin, and heated to prepare cross prepregs and UD prepregs in a B-stage state. The heating time and heating temperature are appropriately set depending on the type of resin and the amount of resin (resin amount) attached to the woven fabric and the unidirectional fiber sheet. For example, when the resin is an epoxy resin composition and the resin amount is 20 to 50 wt%, the heating time is 1 to 12 hours and the heating temperature is 80 to 150°C.

[0152] In the first cross prepreg molding step, the cross prepreg is cut to fit the size of a mold. The cross prepreg is attached to the mold and molded. The cross prepreg is attached and molded so that the extension direction of the warp or weft of the fabric is, for example, parallel to the extension direction of the axis of the mold. The cross prepreg may be attached and molded while being exposed to hot air of 50 to 100°C.

[0153] In the honeycomb sheet lamination step, the honeycomb sheet 70 is placed on the area that is to become the predetermined area 112 of the cross prepreg.

[0154] In the second cross prepreg molding process, the cross prepreg is cut to fit the size of the mold. The cross prepreg is attached and molded on the honeycomb sheet 70 and the cross prepreg. The cross prepreg is attached and molded so that the extension direction of the warp or weft of the fabric is parallel to the extension direction of the axis of the mold. The cross prepreg may be attached and molded while being exposed to hot air of 50 to 100°C.

[0155] In the UD prepreg molding step, the UD prepreg is attached onto the cross prepreg and molded so that the fibers of the unidirectional fiber sheet are, for example, parallel to the extension direction of the axial core of the mold. The region where the UD prepreg is attached onto the cross prepreg and molded includes at least the region that will become the predetermined region 112 of the outer container 14. From the viewpoints of increasing the rigidity of the outer container 14 and suppressing deformation of the outer container 14, it is preferable that the UD prepreg is attached onto the entire region of the outer container 14 and molded.

[0156] In the curing step, the laminated prepregs are cured by heating and pressurization. For example, the curing method may be an autoclave molding method using a high-pressure cooker. This allows the prepregs to be cured uniformly.

[0157] In the demolding step, the prepreg is cooled to room temperature and removed from the mold, thereby obtaining the second part of the outer container 14.

[0158] The third part of the outer container 14 can be produced by the same production method as the production method of the bottom part 123. Then, the first part and the third part of the outer container 14 are airtightly joined. The joining method can be the same as the joining method of the bottom part 123 and the cylindrical part 122.

[0159] The parts thus formed are joined together to complete the insulated container 10. Specifically, the second cylindrical container 22 is airtightly joined to the cylindrical portion 132 of the cylindrical container 13. Next, the refrigerant injection tube 12 is airtightly joined to the cylindrical container 13. Furthermore, the first, second, and third parts of the outer container 14 are each arranged to surround the inner container 11 and are airtightly joined together.

[0160] Next, the air in gap 15 is exhausted using a vacuum pump or the like through a pre-formed or newly formed air hole, and when the pressure in gap 15 falls below a reference value, the air hole is airtightly sealed using resin or the like. This completes the thermally insulated container 10. The same method as that used to join bottom portion 123 and cylindrical portion 122 can be used to join the various parts.

[0161] The heat-insulating container 10 described above in the first embodiment can be used as a heat-insulating container for use in the medical field, for example. Application examples using the heat-insulating container 10 will be described below.

[0162] [Application example 1] An example of an application of the heat-insulating container 10 is a magnetospinometer 60.

[0163] As shown in FIG. 9, the spinal cord magnetometer 60 includes a superconducting quantum interferometer 17 for detecting a magnetic field generated from a living body 18, and an insulating container 10. The insulating container 10 includes an inner container 11 and an outer container 14 surrounding the inner container 11 via a gap 15. The inner container 11 includes a cylindrical container 13 having a container section 23 for storing a refrigerant 16 therein, a refrigerant injection tube 12 attached to the cylindrical container 13, and a second cylindrical container 22 having a container section 24 for storing the refrigerant 16 therein. The superconducting quantum interferometer 17 is contained in the second cylindrical container 22 in a state where it is immersed in the refrigerant 16 stored in the second cylindrical container 22. The living body 18 is laid down so that the spinal cord portion of the living body 18 and the measurement surface 19 of the superconducting quantum interferometer 17 are located on the surface as shown in FIG. 9.

[0164] 9, a predetermined region of the outer container 14 has a structure in which a woven fabric 63 is laminated on one side of a honeycomb sheet 71 and a woven fabric 64 is laminated on the other side. The superconducting quantum interferometer 17 is housed in the second cylindrical container 22 in a state where it is immersed in the refrigerant 16. The measurement surface 19 faces the honeycomb sheet 71.

[0165] The base material constituting the predetermined region 112 of the outer container 14 may include a woven fabric 63 and a unidirectional fiber sheet. The unidirectional fiber sheet is laminated between the honeycomb sheet 71 and the woven fabric 63. The unidirectional fiber sheet may be laminated on the woven fabric 63. The unidirectional fiber sheet may be laminated between the honeycomb sheet 71 and the woven fabric 64. The unidirectional fiber sheet may be laminated under the woven fabric 64. From the viewpoint of ensuring the rigidity of the outer container 14 and suppressing deformation of the outer container 14 due to external pressure and external stress, the unidirectional fiber sheet is preferably laminated so that the fibers are parallel to the extending direction of the axis of the second cylindrical container 22.

[0166] The base material constituting the predetermined region 111 of the second cylindrical container 22 may include a woven fabric and a unidirectional fiber sheet. From the viewpoint of ensuring the rigidity of the predetermined region 111 of the second cylindrical container 22 and from the viewpoint of suppressing deformation of the second cylindrical container 22 due to internal pressure, it is preferable that the fibers of this unidirectional fiber sheet are perpendicular to the extending direction of the axis of the second cylindrical container 22.

[0167] Furthermore, when the base material constituting the predetermined region 112 of the outer container 14 includes a unidirectional fiber sheet, the measurement surface 19 of the superconducting quantum interferometer 17 faces the surface of the unidirectional fiber sheet constituting the predetermined region 112 of the outer container 14. When the base material constituting the predetermined region 111 of the second cylindrical container 22 includes a unidirectional fiber sheet, the measurement surface 19 of the superconducting quantum interferometer 17 faces the surface of the unidirectional fiber sheet constituting the predetermined region 111 of the second cylindrical container 22.

[0168] [effect] The heat-insulating container 10 and the magnetospinometer 60 using the same provide the following effects.

[0169] In the insulated container 10, the base material constituting the predetermined region 112 of the outer container 14 includes the woven fabric 63 and the woven fabric 64, and the predetermined region 112 of the outer container 14 includes a honeycomb sheet 71. The woven fabric 63 is laminated on one surface of the honeycomb sheet 71, and the woven fabric 64 is laminated on the other surface. This improves the thermal insulation of the insulated container 10.

[0170] The rigidity of the outer container 14 can be ensured by further including a unidirectional fiber sheet in the base material constituting the predetermined region 112 of the outer container 14. The outer container 14 surrounds the second cylindrical container 22 in a state in which the unidirectional fiber sheet constituting the predetermined region 112 of the outer container 14 faces the unidirectional fiber sheet constituting the predetermined region 111 of the second cylindrical container 22. This allows the insulated container 10 to have sufficient rigidity to withstand external stress, internal pressure, and external pressure when the gap 15 is a vacuum.

[0171] In addition, the base material constituting the predetermined region 111 of the second cylindrical container 22 and the base material constituting the predetermined region 112 of the outer container 14 contain a unidirectional fiber sheet that exhibits high rigidity against stress, so that the predetermined region 111 of the second cylindrical container 22 and the predetermined region 112 of the outer container 14 have rigidity. That is, when the same rigidity as that exhibited by a configuration consisting of only a woven fabric is exhibited by a configuration consisting of a woven fabric and a unidirectional fiber sheet, the thickness of the wall can be made thin. That is, the spinal cord magnetometer 60 using the thermally insulated container 10 can shorten the distance (lift-off) from the measurement surface 19 of the superconducting quantum interference meter 17 to the spinal cord (measurement site) of the living body 18.

[0172] Furthermore, the magnetospinograph 60 using the insulated container 10 equipped with the refrigerant injection tube 12 can reduce the heat conduction from the outside to the cylindrical container 13 and the second cylindrical container 22 via the refrigerant injection tube 12. This allows the refrigerant 16 to be stored in the insulated container 10 for a long period of time, thereby extending the operating time of the magnetospinograph 60. EXAMPLES

[0173] In order to evaluate the thermal insulation of the outer container 14 constituting the insulated container 10, samples were prepared according to the configurations of the examples and comparative examples shown in Table 1, and the thermal conductivity was measured. Furthermore, in order to evaluate the rigidity due to differences in the laminated configuration of the wall constituting the outer container 14 and the rigidity due to differences in the laminated configuration of the wall constituting the second cylindrical container 22, samples were prepared according to the configurations of the examples and comparative examples shown in Tables 1 and 2, and the bending strength and bending modulus were measured. Note that the present invention is not limited in any way by the following examples.

[0174] The resins, substrates and honeycomb sheets used in the examples and comparative examples are as follows.

[0175] (resin) (1) Matrix resin A (1-1) Base resin: bisphenol A type epoxy resin (Dow Chemical Company, DER383LCL), (1-2) Curing agent: acid anhydride curing agent (Hitachi Chemical Co., Ltd., HN-2000), (1-3) Curing accelerator: N,N-dimethylbenzylamine (Kao Corporation, Kaolizer No. 20).

[0176] (2) Matrix resin B (2-1) Base resin: bisphenol A type epoxy resin (DIC Corporation, EPICLON850), (2-2) Hardener: Amine-based hardener (DICY, manufactured by Nippon Carbide Industries Co., Ltd.), (2-3) Curing accelerator: N,N- Dimethylbenzylamine (Kao Corporation, Kaolizer No. 20).

[0177] (Base material and honeycomb sheet) (1) Fabric (glass): Glass cloth (Arisawa Fiberglass, ECC75 181), (2) Fabric (alumina): Alumina cloth (manufactured by Arisawa Manufacturing Co., Ltd., ALPT5107), (3) Fabric (carbon): Carbon cloth (Arisawa Manufacturing Co., Ltd., CFPH3113), (4) UD (alumina): unidirectional fiber sheet using alumina fiber (manufactured by Arisawa Manufacturing Co., Ltd., UDP-AL / CR8), (5) UD (glass): unidirectional fiber sheet using glass fiber (manufactured by Arisawa Manufacturing Co., Ltd., UDP-GF / CR8), (6) UD (carbon): Unidirectional fiber sheet using carbon fiber (manufactured by Arisawa Manufacturing Co., Ltd., UDP-CF / CR8), (7) Honeycomb sheet A (manufactured by TASUNS, honeycomb core) thickness 1.2 mm, (8) Honeycomb sheet B (manufactured by TASUNS, honeycomb core) thickness 7.0 mm.

[0178] Resins were prepared for impregnating the substrates. (1) Preparation of resin (1-1) Preparation of resin used in prepreg with woven substrate The base resin, curing agent, and curing accelerator for matrix resin A were used. First, 100 parts by weight of the base resin, 88 parts by weight of the curing agent, and 0.8 parts by weight of the curing accelerator were added to a container. After that, it was stirred at room temperature, 700 rpm, and 60 minutes with a high-speed mixer to obtain matrix resin A. The viscosity at this time was 500 mPa s.

[0179] (1-2) Preparation of resin used for prepreg with UD substrate The base resin, curing agent, and curing accelerator for matrix resin B were used. First, 100 parts by weight of the base resin, 88 parts by weight of the curing agent, and 0.8 parts by weight of the curing accelerator were added to a container. After that, it was stirred at room temperature, 700 rpm, and 60 minutes with a high-speed mixer to obtain matrix resin B. The viscosity at this time was 500 mPa s.

[0180] The prepared resin was used to make a prepreg. (2) Prepreg Preparation (2-1) Preparation of cross prepreg using woven fabric as the base material The fabric was impregnated with matrix resin A so that the amount of resin after curing was 35 wt %. Next, it was dried at 130°C for 10 minutes to obtain a B-stage prepreg with a resin amount of 35 wt %.

[0181] (2-2) Preparation of UD prepreg using UD as the base material The UD was impregnated with matrix resin B so that the amount of resin after curing was 35 wt%. Next, it was dried at 130°C for 10 minutes to obtain a UD prepreg in a B-stage state with a resin amount of 35 wt%.

[0182] The preparation of samples used in each measurement, the measurement method and evaluation were carried out as follows.

[0183] (3) Preparation of a measurement sample for evaluating the wall constituting the outer container 14 A measurement sample for measuring the thermal conductivity, bending strength, and bending modulus of elasticity of the wall constituting the outer container 14 was prepared as follows. First, the prepregs and honeycomb sheets prepared in (2-1) and (2-2) were laminated to have the same laminated configuration as that of Examples 1 to 10 and Comparative Example 1 shown in Table 1. When laminating the cross prepregs, the cross prepregs were laminated so that the angle between the warp yarn and one side of the prepreg of the lowest layer was set as a reference. When laminating the UD prepregs, the cross prepregs were laminated so that the angle between the one side of the prepreg of the lowest layer that was set as a reference when laminating the cross prepregs was set as a reference and the angle between the one side of the prepreg and the fibers constituting the UD prepreg was set as a reference. The predetermined angle refers to the angle shown in the Examples and Comparative Examples listed in Table 1. Next, the laminated prepregs were pressed under conditions of 130°C, 90 minutes, and 0.29 MPa so that the resin amount after curing was 35 wt% and the thickness after curing was 2.5 mm. After pressing, a measurement sample in the C-stage state was obtained.

[0184] The measurement samples for measuring bending strength and bending modulus were cut into rectangles with a width of 10 mm and a length of 20 mm to adjust the size. The measurement samples in Examples 1 to 4 and Comparative Example 1 were cut so that the long side direction of the measurement sample was parallel to the warp yarn of the cross prepreg constituting the measurement sample. The measurement samples in Examples 5 to 10 were cut so that the long side direction of the measurement sample was parallel to the fiber of the UD prepreg constituting the measurement sample. The reason why the measurement samples in Examples 5 to 10 were cut so that the long side direction of the measurement sample was parallel to the fiber of the UD prepreg is to appropriately evaluate the difference in effect (rigidity) due to the difference in the extension direction of the fiber when the unidirectional fiber sheet is used as a base material constituting the wall of the thermal insulation container 10.

[0185] The measurement sample for measuring thermal conductivity was prepared by cutting a 2.5 mm thick flat plate-shaped measurement sample prepared for measuring thermal conductivity, bending strength, and bending modulus into a circle with a diameter of 50 mm.

[0186] (4) Preparation of a measurement sample for evaluating the wall constituting the second cylindrical container 22 A measurement sample for measuring the bending strength and bending modulus of the wall constituting the second cylindrical container 22 was prepared as follows. The prepregs prepared in (2-1) and (2-2) were laminated to have the same laminated structure as the laminated structures of Examples 11 to 18 shown in Table 2. When laminating, the cross prepregs were laminated so that the angle between the side of the bottom layer prepreg and the warp yarn was a predetermined angle, with one side of the bottom layer prepreg being the reference when laminating the cross prepreg. When laminating the UD prepreg, the UD prepreg was laminated so that the angle between the side of the bottom layer prepreg and the fibers constituting the UD prepreg was a predetermined angle, with one side of the bottom layer prepreg being the reference when laminating the cross prepreg. The predetermined angle refers to the angle shown in the examples shown in Table 2. The laminated prepreg was pressed under conditions of 130°C, 90 minutes, and 0.29 MPa so that the amount of resin after curing was 35 wt% and the thickness after curing was 2.5 mm. After pressing, a measurement sample in a C-stage state was obtained. Further, the obtained measurement sample was cut into a rectangle with a width of 10 mm and a length of 20 mm. The measurement samples in Examples 11 to 13 were cut so that the long side direction of the measurement sample was parallel to the warp yarn of the cross prepreg constituting the measurement sample. The measurement samples in Examples 14 to 18 were cut so that the long side direction of the measurement sample was parallel to the fiber of the UD prepreg constituting the measurement sample.

[0187] (5) Measurement of thermal conductivity Thermal conductivity (W / m K) was measured using a measuring device (ARC-TC-1000, manufactured by Agne Technology Center Co., Ltd.) by the temperature gradient method. The measurement conditions were in accordance with ASTM E1225.

[0188] (6) Measurement of bending strength and bending modulus The bending strength and bending modulus were measured using an autograph tester (AG-10, manufactured by Shimadzu Corporation). The measurements were performed by three-point bending (support distance 10 mm, test speed 2 mm / min). When performing the measurements, the measurement sample was placed on the tester so that the supports at both ends of the three-point bending were located at both ends in the longitudinal direction of the measurement sample. The bending strength and bending modulus were calculated from the obtained maximum bending stress (breaking load) in accordance with JIS K7017.

[0189] Table 1 shows the measurement results of thermal conductivity, bending strength, and bending modulus of elasticity of Examples 1 to 10 and Comparative Example 1. Table 2 shows the measurement results of bending strength and bending modulus of elasticity of Examples 11 to 18.

[0190] [Table 1]

[0191] [Table 2]

[0192] Comparing the Examples shown in Table 1, for example, it was found that Example 1 could reduce the thermal conductivity by about 80% compared to Comparative Example 1. Also, it was found that Example 8 could reduce the thermal conductivity by about 50% compared to Comparative Example 1 while maintaining the bending strength at about 70%.

[0193] In addition, when comparing the Examples and Comparative Examples shown in Table 2, it was found that, for example, the bending strength of Example 13 was about 1.7 times that of Example 11 when the thickness was the same. In addition, it was found that the bending modulus of Example 17 was about 2.2 times that of Example 11.

[0194] From these measurement results, it is possible to improve the thermal insulation of the insulating container 10 by forming the wall constituting the predetermined region 112 of the outer container 14 surrounding the second cylindrical container 22 in the laminated configuration described in Examples 1 to 10. Furthermore, by forming the wall constituting the predetermined region 111 of the second cylindrical container 22 in the laminated configuration described in Examples 11 to 18, it is possible to make the wall constituting the second cylindrical container 22 thinner while maintaining the rigidity of the wall constituting a conventional insulating container. Furthermore, by using such an insulating container 10 as the insulating container of the magnetospinometer 60, it is possible to shorten the distance (lift-off) from the measurement surface 19 of the superconducting quantum interference meter 17 to the measurement site of the spinal cord, and it becomes possible to measure an ultra-weak magnetic field.

[0195] From the above results, it is possible to provide an insulating container according to the embodiment that has excellent insulating properties and has a thin wall, and a magnetospinometer using the same.

[0196] The present invention allows various embodiments and modifications without departing from the broad spirit and scope of the present invention. The above-described embodiments are for the purpose of explaining the present invention and do not limit the scope of the present invention. That is, the scope of the present invention is indicated by the claims, not the embodiments. Various modifications made within the scope of the claims and within the scope of the meaning of the invention equivalent thereto are considered to be within the scope of the present invention.

[0197] This application is based on Japanese Patent Application No. 2021-090086, filed on May 28, 2021. The specification, claims, and drawings of Japanese Patent Application No. 2021-090086 are incorporated herein by reference in their entirety. [Explanation of symbols]

[0198] 10 Insulated container, 11 Inner container, 12 Refrigerant injection pipe, 13 Cylindrical containers, 131 Top part, 122, 132 cylindrical portion, 123, 133 bottom part, 132O outer layer, 132I Inner layer, 111, 112 predetermined area, 101 Measurement object, 102 Measuring equipment, 14 outer container, 15 void, 16 Refrigerants, 17 Superconducting quantum interference 18 Living organisms, 19 Measurement surface, 21 Base material, 22 a second cylindrical container, 23, 24 Storage section, 60 magnetospinometer, 63, 64 textiles, 65 Stopper thread, 66 Flat threads, 70, 71 Honeycomb sheet.

Claims

1. The container has an inner container and an outer container surrounding the inner container via a gap, The inner container and the outer container are made of fiber-reinforced plastic in which a base material containing fiber is impregnated with resin, the inner container comprises a cylindrical container and a second cylindrical container each having a storage portion for storing a refrigerant therein, and a refrigerant injection pipe for injecting the refrigerant into the cylindrical container; The second cylindrical container has a storage portion that communicates with the storage portion of the cylindrical container, a base material constituting a predetermined region of the second cylindrical container and a predetermined region of the outer container includes a woven fabric; a heat-insulating container, the predetermined region of the outer container further including a honeycomb sheet, the woven fabric being laminated on one surface and the other surface of the honeycomb sheet; A superconducting quantum interference meter for detecting a magnetic field generated from a living body, the superconducting quantum interference meter is immersed in a coolant stored in the container portion of the second cylindrical container; A magneto-spinal fluid dynamics meter, wherein a measurement surface of the superconducting quantum interference meter faces the predetermined area of ​​the second cylindrical container and the predetermined area of ​​the outer container.

2. 2. The magnetospinograph according to claim 1, wherein the woven fabric is made of at least one material selected from the group consisting of glass fiber, alumina fiber, and carbon fiber.

3. The spinal cord magnetometer according to claim 1 or 2, wherein the base material constituting the specified region of the outer container further includes a unidirectional fiber sheet in which a plurality of fibers are aligned in one direction, and the unidirectional fiber sheet is laminated on at least one of the one and other surfaces of the honeycomb sheet.

4. 4. The magnetospinograph according to claim 3, wherein the fibers of the unidirectional fiber sheet constituting the predetermined region of the outer container are parallel to an extending direction of an axis of the second cylindrical container.

5. 4. The magnetospinometer according to claim 3, wherein the base material constituting the predetermined region of the second cylindrical container further includes a unidirectional fiber sheet formed by aligning a plurality of fibers in one direction.

6. 6. The magnetospinograph according to claim 5, wherein the fibers of the unidirectional fiber sheet constituting the predetermined region of the second cylindrical container are perpendicular to the extending direction of the axis of the second cylindrical container.

7. The spinal cord magnetometer of claim 5, wherein the outer container surrounds the second cylindrical container in a state in which the unidirectional fiber sheet constituting the specified area of ​​the outer container faces the unidirectional fiber sheet constituting the specified area of ​​the second cylindrical container.

8. 4. The magnetospinograph according to claim 3, wherein the unidirectional fiber sheet constituting the predetermined region of the outer container is made of at least one fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber.

9. 6. The magnetospinograph according to claim 5, wherein the unidirectional fiber sheet constituting the predetermined region of the second cylindrical container is made of at least one fiber selected from the group consisting of glass fiber, alumina fiber, and carbon fiber.

10. 3. The magnetospinometer according to claim 1, wherein the honeycomb sheet has a thickness of 1 to 7 mm.

11. The magnetospinograph according to claim 1 or 2, wherein the resin includes an epoxy resin.

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