Three-dimensionally formed insulator and method for manufacturing the same

Abstract

To provide a three-dimensionally molded insulator that can reduce a dead space generated between a circuit board and the three-dimensionally molded insulator and enables effective utilization of the space in which the circuit board is housed, and to provide a method for manufacturing a three-dimensionally molded insulator that can produce a three-dimensionally molded insulator with high shape accuracy.SOLUTION: A three-dimensionally shaped insulator according to the present invention is a three-dimensionally shaped insulator that is placed over a component to which voltage is applied, and is shaped to have a recess that includes a bottom and a wall portion provided at the end of the bottom, and is used with the component inserted into the recess.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to three-dimensionally shaped insulation and a method for making three-dimensionally shaped insulation. [Background technology]

[0002] Electronic devices house circuit boards that include a substrate and various voltage application components mounted on the substrate, and a predetermined insulation distance is maintained around such circuit boards to prevent electrical short circuits.

[0003] For example, Patent Document 1 discloses a flame-retardant resin composition comprising a polycarbonate resin, a phosphate ester compound, and a fibrous material. It also discloses an insulating sheet formed from this flame-retardant resin composition. The insulating sheet is useful because it can be stored in narrow gaps within electronic devices. By disposing the insulating sheet between the conductors present around a circuit board, for example, it is possible to shorten the insulation clearance. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-030209 Summary of the Invention [Problem to be solved by the invention]

[0005] However, because the height (thickness) of voltage-applied components is not uniform, the thickness of the circuit board varies accordingly. Conventional insulating sheets are flat and are therefore placed to fit the tallest voltage-applied component. This creates a problem of large dead spaces between the board and the insulating sheet (around the voltage-applied component). This dead space is one of the factors that hinders the miniaturization of electronic devices.

[0006] Furthermore, shortening the insulating spatial distance around any voltage-applied component, not limited to circuit boards, can contribute to the miniaturization of electronic devices.

[0007] The object of the present invention is to provide a three-dimensional molded insulator that can reduce the dead space that occurs around voltage-applied components and enable effective use of the space in which the voltage-applied components are housed, and a method for manufacturing a three-dimensional molded insulator that can produce three-dimensional molded insulators with high shape accuracy. [Means for solving the problem]

[0008] These objects can be achieved by the present invention as set forth in (1) to (12) below. (1) A three-dimensionally shaped insulator that is placed over a component to which voltage is applied, The container is molded into a shape having a recess including a bottom and a wall portion provided at an end of the bottom, A three-dimensionally molded insulator characterized in that the component is inserted into the recess when used.

[0009] (2) The device is used by covering a circuit board including the component and a board on which the component is mounted, The three-dimensionally molded insulator according to (1) above, which is molded into a shape having the recess and a flat portion connected to the recess.

[0010] (3) The three-dimensionally molded insulator according to (2) above, having a through hole passing through the flat portion in the thickness direction.

[0011] (4) The three-dimensionally molded insulator according to (3) above, wherein the thickness of the wall portion is 20% or more and 95% or less of the thickness of the flat portion.

[0012] (5) The three-dimensionally molded insulator according to (3) or (4) above, wherein the thickness of the flat portion is 0.05 mm or more and 1.00 mm or less. (6) A three-dimensionally molded insulator according to any one of (1) to (4) above, which contains a flame retardant.

[0013] (7) A three-dimensionally molded insulator according to any one of (1) to (4) above, which is mainly made of a thermoplastic resin.

[0014] (8) The three-dimensionally molded insulator according to (7), wherein the thermoplastic resin includes an aromatic polycarbonate resin.

[0015] (9) A three-dimensionally molded insulator according to any one of (1) to (4) above, having a comparative tracking index (CTI), which is an index of tracking resistance measured in accordance with ASTM D3638, of 600 V or more.

[0016] (10) A three-dimensional molded insulator according to any one of (1) to (4) above, whose flame retardancy measured in accordance with the UL94 standard is V-0 or VTM-0 for a test piece having a thickness of 0.4 mm or more.

[0017] (11) A method for producing a three-dimensionally molded insulator according to any one of (1) to (4) above, A method for manufacturing a three-dimensional molded insulator, characterized in that a flat thermoplastic insulating sheet is subjected to secondary processing including thermoforming to form the recesses.

[0018] (12) The method for producing a three-dimensionally molded insulator according to (11) above, wherein the thermoforming is vacuum forming or vacuum-pressure forming. [Effects of the Invention]

[0019] According to the present invention, a three-dimensionally molded insulator can be obtained that can reduce the dead space that occurs around voltage application components and enable effective use of the space in which the voltage application components are housed. Furthermore, according to the present invention, it is possible to manufacture a three-dimensionally molded insulator with high shape accuracy. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a perspective view illustrating a three-dimensionally shaped insulator according to an embodiment and a circuit board on which the three-dimensionally shaped insulator is to be placed. FIG. [Figure 2]2 is a cross-sectional view of the circuit board shown in FIG. 1 taken along the line AA. [Figure 3] FIG. 3 is a cross-sectional view showing only the three-dimensionally shaped insulator of FIG. 2. [Figure 4] FIG. 3 is a cross-sectional view showing a modified example of the circuit board of FIG. [Figure 5] FIG. 10 is a top view showing a three-dimensionally shaped insulator according to a modified example of the embodiment. [Figure 6] FIG. 6 is a cross-sectional view of the bus bar and three-dimensionally formed insulator shown in FIG. 5. [Figure 7] FIG. 10 is a cross-sectional view showing a three-dimensionally shaped insulator according to a modified example. [Figure 8] 1 is a cross-sectional view showing a control device in which a three-dimensionally molded insulator and a circuit board according to an embodiment are housed in a case. [Figure 9] FIG. 9 is a cross-sectional view showing a modified example of the control device of FIG. 8. DETAILED DESCRIPTION OF THE INVENTION

[0021] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A three-dimensionally shaped insulator and a method for manufacturing the same according to the present invention will be described in detail below with reference to preferred embodiments shown in the accompanying drawings.

[0022] 1. Overview of three-dimensionally molded insulators FIG. 1 is a perspective view showing a three-dimensionally shaped insulator 1 according to an embodiment and a circuit board 9 on which the three-dimensionally shaped insulator 1 is to be placed. Note that FIG. 1 illustrates the state before the three-dimensionally shaped insulator 1 is placed on the circuit board 9. In addition, in each drawing of the present application, three mutually orthogonal axes are set as an X-axis, a Y-axis, and a Z-axis, and each axis is indicated by an arrow. Furthermore, the base end side of the arrow is referred to as the negative side of each axis, and the tip end side is referred to as the positive side of each axis. Furthermore, the positive side of the Z-axis is also referred to as "upper," and the negative side of the Z-axis is also referred to as "lower."

[0023] As shown in FIG. 1 , the three-dimensionally molded insulator 1 is used by covering a circuit board 9, for example. The circuit board 9 includes a wiring board 90 having wiring (not shown), a power semiconductor element 91, a bus bar 92, a signal connector 93, and a fixing screw 94. The power semiconductor element 91, the bus bar 92, the signal connector 93, and the fixing screw 94 each protrude upward from the upper surface of the wiring board 90. The power semiconductor element 91 and the bus bar 92 are used under a relatively high voltage. The applied voltage is, for example, 50 V or more, preferably 71 V or more and 10 kV or less. Covering the circuit board 9 with the three-dimensionally molded insulator 1 from above can improve the insulation between the circuit board 9 and other objects (not shown) located above it. This can reduce the spatial distance required for insulation between the circuit board 9 and other objects.

[0024] As shown in FIG. 1 , the three-dimensionally molded insulator 1 is three-dimensionally molded into a shape having a recess 12, more specifically, a shape having a flat portion 11 and a recess 12. Three-dimensional molding refers to molding a sheet-like member into a shape having a recess deeper than the thickness of the member. When viewed from above the Z axis, the insulating sheet 1 has an outer size and shape that overlaps with the wiring board 90. The flat portion 11 is a portion having a flat surface 110 parallel to the top surface of the wiring board 90. The flat surface 110 is the lower surface of the flat portion 11 that faces the top surface of the wiring board 90. Note that an angle deviation of 10 degrees or less is allowed with respect to the parallelism. The recess 12 is a portion recessed upward from the flat surface 110. The position of the recess 12 in a plan view is aligned with the positions of the power semiconductor element 91, bus bar 92, and signal connector 93 arranged on the wiring board 90.

[0025] When the three-dimensionally molded insulator 1 is placed over the circuit board 9, the power semiconductor element 91, bus bar 92, and signal connector 93 are inserted into the recess 12. This allows the top and side surfaces of these components that protrude from the top surface of the wiring board 90 to be covered with the three-dimensionally molded insulator 1. As a result, only a minimal gap is created between the circuit board 9 and the three-dimensionally molded insulator 1, making it possible to reduce dead space compared to conventional methods. In other words, it is possible to reduce the dead space around components to which voltage is applied, such as the power semiconductor element 91, bus bar 92, and signal connector 93. This allows for effective use of the space in which the circuit board 9 is housed.

[0026] Therefore, by using the three-dimensionally shaped insulator 1, it is possible to miniaturize the device on which the circuit board 9 is mounted. The orientation of the three-dimensionally shaped insulator 1 when in use (orientation relative to the vertically upward direction) is not limited to the above. For example, if the upper surface of the above-mentioned wiring board 90 faces downward, the three-dimensionally shaped insulator 1 will be placed on the wiring board 90 from below. In this case, the recess 12 will be a portion recessed downward from the flat surface 110.

[0027] 2. Circuit board Prior to describing the three-dimensionally shaped insulator 1, a detailed description will be given of the circuit board 9. The circuit board 9 is not particularly limited as long as it includes a substrate and components that protrude from the surface of the substrate and to which a voltage is applied.

[0028] As described above, the circuit board 9 shown in FIG. 1 includes the wiring board 90, the power semiconductor element 91, the bus bar 92, the signal connector 93, and the fixing screw 94. FIG. 2 is a cross-sectional view of the circuit board 9 shown in FIG. 1 taken along the line AA.

[0029] As shown in FIG. 2, the wiring substrate 90 includes an insulating layer 901, a wiring layer 902, through-wires 903, and thermal vias 904.

[0030] The power semiconductor elements 91 are semiconductor elements that perform high-power switching and the like. Examples of the power semiconductor elements 91 include an IGBT (insulated gate bipolar transistor) and a power MOSFET (metal oxide semiconductor field effect transistor). FIG. 1 shows six power semiconductor elements 91, each protruding upward from the upper surface of the wiring board 90. Each power semiconductor element 91 is in contact with a thermal via 904 so as to be able to dissipate heat.

[0031] Bus bar 92 is a conductor that connects circuit board 9 and a power source. Bus bar 92 is made of, for example, a metal plate or rod. Bus bar 92 shown in FIG. 2 protrudes upward from the upper surface of wiring board 90 and is bent sideways (toward the negative X-axis) midway. Bus bar 92 is electrically connected to wiring board 90 via through-wires 903. Note that bus bar 92 shown in FIG. 1 includes bus bars 921 and 922 through which currents flow in different directions.

[0032] The signal connector 93 is a connector into which a signal line is inserted. The signal line is used, for example, to transmit and receive signals between the circuit board 90 and an external control device. The signal connector 93 protrudes upward from the top surface of the wiring board 90.

[0033] The fixing screws 94 penetrate the four corners of the wiring board 90 in the thickness direction. The fixing screws 94 fix the wiring board 90 to a housing or the like (not shown). The heads of the fixing screws 94 protrude upward from the top surface of the wiring board 90.

[0034] In the circuit board 9 as described above, a voltage is applied to the power semiconductor elements 91, the bus bars 92, and the signal connectors 93. Since a high voltage is applied to the power semiconductor elements 91 and the bus bars 92 in particular, insulation by the three-dimensional molded insulator 1 is effective.

[0035] The component to which a voltage is applied is not limited to the above, and may be any component to which a voltage is applied. Specific examples other than those mentioned above include a battery, a capacitor, a diode, a coil, a resistor, a relay, a transformer, a switch, a connector, a terminal, etc.

[0036] In addition, components that are not directly subjected to voltage but are in contact with components that are directly subjected to voltage may also be subject to voltage application unintentionally, and are therefore also included in the "components to which voltage is applied." Specific examples of such components include heat sinks, heat spreaders, and heat pipes.

[0037] 3. Composition of three-dimensionally molded insulator Next, the configuration of the three-dimensionally molded insulator 1 will be described.

[0038] 3.1. Shape of three-dimensionally molded insulator As described above, the three-dimensionally molded insulator 1 shown in Fig. 1 has a plurality of recesses 12 that fit the components protruding from the upper surface of the wiring board 90. The recesses 12 are open at the bottom. The three-dimensionally molded insulator 1 is used with each component inserted through the openings.

[0039] The recess 12 includes a recess 121 into which the power semiconductor element 91 is inserted, a recess 122 into which the bus bar 92 is inserted, and a recess 123 into which the signal connector 93 is inserted. The recesses 121, 122, and 123 are each formed to match the outer size and shape of the component to be inserted. This minimizes the gap between each component and the recesses 121, 122, and 123. This reduces dead space. In other words, the area of the recesses 121, 122, and 123 in a plan view can be minimized, thereby maximizing the area of the flat portion 11. This allows for more effective use of the space above the flat portion 11 (the space around the component to which voltage is applied) than when a conventional flat insulating sheet is used.

[0040] Furthermore, recess 12 covers not only the top surface of each component but also the side surface, thereby preventing dust and other foreign matter from adhering to the side surface of each component and preventing moisture and the like from being adsorbed thereon.

[0041] Furthermore, terminals and the like may be exposed on the side surfaces of each component. The recess 12 also effectively serves to insulate such terminals and the like. For example, the provision of the recess 12 makes it possible to shorten the spatial distance L1 (spatial distance required for insulation between components) required for insulation between the bus bar 92 and the power semiconductor element 91 shown in FIG. 2. This allows the circuit board 9 to be made smaller.

[0042] FIG. 3 is a cross-sectional view showing only the three-dimensionally shaped insulator 1 of FIG. The recess 12 shown in Fig. 3 includes a bottom 12a and wall portions 12b. The bottom 12a is a portion that covers the upper surfaces of the power semiconductor elements 91 and the bus bars 92. The wall portions 12b are portions that rise down from the end of the bottom 12a and cover the side surfaces of the power semiconductor elements 91 and the bus bars 92. The shapes of the bottom 12a and the wall portions 12 are not limited to the shapes shown in Fig. 3. The connection portion between the bottom 12a and the wall portions 12b may be rounded or chamfered.

[0043] Furthermore, by forming the recess 12 to have an appropriate size and shape, it is possible to make the separation distance S2 between the inner side surface of the recess 12 and components such as the power semiconductor element 91 sufficiently close, as shown in Fig. 2. This makes it possible to more effectively reduce the dead space and effectively protect the side surfaces of each component.

[0044] The separation distance S2 is not particularly limited, but is preferably 10 mm or less, more preferably 7 mm or less, and even more preferably 5 mm or less. This allows dead space to be sufficiently reduced and each component to be protected more effectively. As will be described later, the three-dimensionally molded insulator 1 has good tracking resistance. Therefore, even if the separation distance S2 is within the above range, tracking is unlikely to occur. On the other hand, when taking into consideration the heat dissipation efficiency from the components, stress on the components, ease of assembly, etc., the separation distance S2 is preferably 0.5 mm or more, and more preferably 1 mm or more.

[0045] Although not shown, the distance between the ceiling surface of the recess 12 and components such as the power semiconductor element 91 is also the same as the distance S2.

[0046] On the other hand, by forming the recess 12 to have an appropriate size and shape, it is possible to make the separation distance S1 between the flat surface 110 of the flat portion 11 and the wiring board 90, as shown in Fig. 2, sufficiently close. Furthermore, by making the separation distance S1 shorter, it becomes easier to prevent foreign matter such as dust from adhering to the upper surface of the wiring board 90, and to prevent moisture and the like from being adsorbed. This also makes it easier to prevent creeping discharge and subsequent tracking that occur between the bus bar 92 and the power semiconductor element 91.

[0047] The separation distance S1 is not particularly limited, but is preferably 15 mm or less, more preferably 10 mm or less, and even more preferably 5 mm or less. This allows for sufficient reduction of dead space. In the example shown in FIG. 2, by setting the separation distance S1 within the above range, the probability that the three-dimensionally shaped insulator 1 will be interposed between the power semiconductor element 91 and the bus bar 921 increases, and the three-dimensionally shaped insulator 1 can be brought sufficiently close to the wiring board 90 between them. This makes it possible to suppress creeping discharge and tracking that occur between them, and to sufficiently shorten the spatial distance L1 required between them.

[0048] The recess 12 includes recesses 121 into which the power semiconductor elements 91 are inserted one by one. This allows each power semiconductor element 91 to be protected individually. Also, the distance required for insulation between the power semiconductor elements 91 can be shortened. Note that the recess 121 may be configured to allow two or more power semiconductor elements 91 (components) to be inserted.

[0049] Recess 12 includes recess 122 into which bus bars 921, 922 are inserted one by one. This allows bus bars 921, 922 to be individually protected. Also, it is possible to reduce the distance required for insulation between bus bars 921, 922. Note that recess 122 may be configured to receive two or more bus bars 92 (components).

[0050] 1, bus bars 921 and 922 are aligned along the Y axis. However, bus bars 921 and 922 may be configured to partially overlap along the Z axis.

[0051] FIG. 4 is a cross-sectional view showing a modification of the circuit board 9 of FIG. In FIG. 4, bus bar 921 and bus bar 922 partially overlap along the Z axis. In this portion, positive and negative currents flow closely together. This causes magnetic fluxes generated by the currents to cancel each other out, reducing the inductance component. Therefore, the configuration shown in FIG. 4 can achieve a circuit board 9 with a reduced inductance component in bus bar 92. This reduces surge voltages in circuit board 9.

[0052] Furthermore, three-dimensionally molded insulator 1 is interposed between busbar 921 and busbar 922. This prevents dielectric breakdown and the like even when busbars 921 and 922 are brought sufficiently close to each other. As a result, the inductance component can be reduced more effectively.

[0053] 4, the side surface of busbar 921 on the positive side of the X axis and the side surfaces on the positive and negative sides of the Y axis (not shown in FIG. 4) are covered by the inner surface of recess 122. Therefore, even if busbars 921 and 922 are brought sufficiently close to each other, creeping discharge can be effectively suppressed.

[0054] Fig. 5 is a top view showing a three-dimensionally shaped insulator 1 according to a modified example of the embodiment, and Fig. 6 is a cross-sectional view of the bus bar 92 and the three-dimensionally shaped insulator 1 shown in Fig. 5.

[0055] The three-dimensionally shaped insulator 1 shown in Fig. 5 is a modified example of the three-dimensionally shaped insulator 1 shown in Fig. 3, and is provided, for example, at a position away from the circuit board 9. Specifically, the bus bars 921 and 922 shown in Fig. 4 may protrude from the wiring board 90 and extend toward the negative side of the X-axis. The three-dimensionally shaped insulator 1 shown in Fig. 5 is preferably used in the extension portions of the bus bars 921 and 922.

[0056] Bus bars 921 and 922 shown in Fig. 5 correspond to the above-mentioned extensions. In the extensions, bus bars 921 and 922 overlap each other along the Z axis. In the overlapping portion, bottom portion 12a of three-dimensionally shaped insulator 1 is disposed between bus bars 921 and 922. Furthermore, wall portion 12b of three-dimensionally shaped insulator 1 shown in Fig. 5 rises from the end of bottom portion 12a toward the positive side of the Z axis, as shown in Fig. 6. As a result, the side surface of bus bar 922 is covered by wall portion 12b.

[0057] 5 and 6, the dead space around the bus bar 922 can be reduced. In other words, the provision of the wall portion 12b reduces the insulating spatial distance on the sides of the bus bar 922, making it possible to place any component on the sides of the bus bar 922. This reduces the space that would conventionally be dead space.

[0058] 5 is used with the bus bar 922 inserted in the recess 12, which prevents misalignment between the bus bar 922 and the three-dimensionally shaped insulator 1. This prevents the three-dimensionally shaped insulator 1 from falling off even when vibrations or the like are applied.

[0059] Furthermore, the three-dimensionally shaped insulator 1 shown in FIG. 1 has a through hole 13 that penetrates the flat portion 11 in the thickness direction. The through hole 13 is provided to coincide with the position of a fixing screw 94. By providing the through hole 13, the fixing screw 94 can be rotated even when the three-dimensionally shaped insulator 1 is placed on the circuit board 9. This makes it possible to screw the circuit board 9 to a case or the like with the three-dimensionally shaped insulator 1 placed on the circuit board 9, improving assembly workability. In this case, it is preferable that the inner diameter of the through hole 13 is equal to or larger than the outer diameter of the head of the fixing screw 94. This makes it easier to rotate the fixing screw 94.

[0060] When the fixing screw 94 is fastened to the circuit board 9, the head of the fixing screw 94 may be located above the three-dimensionally shaped insulator 1. This allows the fixing screw 94 to fix the three-dimensionally shaped insulator 1 together with the circuit board 9. In this case, it is preferable that the inner diameter of the through hole 13 is smaller than the outer diameter of the head of the fixing screw 94.

[0061] Furthermore, the planar shape of the through-hole 13 is not limited to a closed shape, and may be a shape that is partially open outward.

[0062] The thickness t11 of the flat portion 11 of the three-dimensionally molded insulator 1 is not particularly limited, but is preferably 0.05 mm or more and 1.00 mm or less, more preferably 0.10 mm or more and 0.90 mm or less, and even more preferably 0.20 mm or more and 0.80 mm or less. This results in a three-dimensionally molded insulator 1 that is excellent in flame retardancy, tracking resistance, and insulation, and is relatively easy to manufacture. If the thickness t11 of the flat portion 11 is below the lower limit, the flame retardancy, tracking resistance, and insulation may be reduced. On the other hand, the thickness t11 of the flat portion 11 may be above the upper limit, but in that case, the three-dimensionally molded insulator 1 may be too thick, reducing flexibility and making it difficult to handle, reducing heat dissipation and shape accuracy, and increasing the difficulty of manufacturing.

[0063] Furthermore, the thickness t12b of the wall portion 12b is preferably 20% to 95% of the thickness t11 of the flat portion 11, more preferably 30% to 90%, and even more preferably 50% to 90%. If the thickness t12b of the wall portion 12b is within the above range, the wall portion 12b has sufficient rigidity to support the shape of the recess 12, and the dead space on the side of the recess 12 can be further reduced.

[0064] If the thickness t12b of the wall 12b is less than the lower limit, the rigidity of the wall 12b may be insufficient. On the other hand, if the thickness t12b of the wall 12b is greater than the upper limit, the effect of reducing the dead space on the side of the recess 12 may be reduced.

[0065] The external shape of the three-dimensionally molded insulator 1 shown in FIG. 1 is, for example, a shape that overlaps the entire circuit board 9, but it may be smaller or larger than this.

[0066] Furthermore, it is preferable that recess 12 covers the entire side surface of the component protruding from the top surface of wiring board 90, such as recess 121, but it may also cover only a portion of the side surface of the component, such as recesses 122 and 123.

[0067] The depth of recess 12 is set according to the height of the component, so is not particularly limited, but may be 0.5 mm to 100 mm, or 1 mm to 50 mm. Within such ranges, a three-dimensionally molded insulator 1 can be realized that is easy to manufacture and has recess 12 into which various components can be inserted with almost no height restrictions.

[0068] 3.2. Materials for Three-Dimensional Molded Insulators Next, the constituent materials of the three-dimensionally molded insulator 1 will be described.

[0069] The three-dimensionally molded insulator 1 contains, for example, a resin material. The proportion of the resin material in the constituent materials of the three-dimensionally molded insulator 1 is preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more. This allows for the three-dimensionally molded insulator 1 to have excellent insulating properties and moldability, and to be easily lightweight.

[0070] Examples of resin materials include various thermoplastic resins such as polyolefin resin, polyamide resin, polyester resin, aromatic polycarbonate resin, aliphatic polycarbonate resin, polyarylate resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polylactic acid, styrene copolymer, polyacetal resin, polyphenylene ether resin, polyphenylene sulfide resin, polymethyl methacrylate resin, and cellulose ester resin, and various thermosetting resins such as polyimide, polyurethane, epoxy resin, and phenolic resin. The first resin and the second resin may be a combination of one or more of these resins.

[0071] Furthermore, the three-dimensionally molded insulator 1 preferably contains a thermoplastic resin as its main material. The main material refers to the above-mentioned ratio. A sheet containing a thermoplastic resin as its main material can be plastically deformed by heat, and has excellent secondary processability. Therefore, the three-dimensionally molded insulator 1 can be produced by thermoforming, and has excellent manufacturability.

[0072] Of these, polyolefin resins, polyamide resins, aromatic polycarbonate resins, and aliphatic polycarbonate resins are preferably used as the thermoplastic resin.

[0073] Furthermore, a resin material with high tracking resistance is preferably used. Tracking resistance refers to the resistance to the phenomenon in which a conductive path (tracking) is formed due to discharge occurring on the surface of an insulator. Such tracking resistance can be quantified, for example, by the comparative tracking index (CTI), which is an index of tracking resistance measured in accordance with ASTM D3638.

[0074] The comparative tracking index CTI of the resin material is preferably 400 V or more, and more preferably 600 V or more, thereby providing a three-dimensional molded insulator 1 with particularly good tracking resistance.

[0075] The glass transition temperature Tg of the resin material is preferably 125°C or higher, and more preferably 130°C or higher but lower than 200°C. This provides heat resistance to the resin material, making it easier to suppress coloration due to carbonization even if creeping discharge occurs in the three-dimensionally molded insulator 1. As a result, the occurrence of poor appearance in the three-dimensionally molded insulator 1 and the deterioration of insulating properties due to carbonization can be suppressed. The glass transition temperature Tg of the resin material is measured by DSC (differential scanning calorimetry). The heating rate in the DSC method is 10°C / min.

[0076] The melt volume rate (MVR) of the resin material at 300°C and a load of 1.2 kg is 5 cm 3 / 10min] or more 30[cm 3 / 10min] or less, and 8 [cm 3 / 10min] or more 20[cm 3 / 10 min or less is more preferable. This improves the moldability of the three-dimensionally molded insulator 1 in secondary processing, particularly in vacuum molding, to prevent defects such as distortion. If the melt volume rate is below the lower limit, the flowability may be insufficient, resulting in reduced moldability. On the other hand, if the melt volume rate is above the upper limit, the impact resistance of the molded body may be reduced. The melt volume rate is measured in accordance with the test method specified in JIS K 7210:2014.

[0077] 3.2.1. Polyolefin resin Examples of polyolefin resins include high-density polyethylene resins, polypropylene resins, polybutene resins, ethylene-(meth)acrylic acid copolymers, ethylene-methyl (meth)acrylate copolymers, ethylene-ethyl (meth)acrylate copolymers, ethylene-vinyl acetate copolymers, maleic anhydride-modified polyethylene, carboxylic acid-modified polyethylene, ethylene-propylene copolymers, and ethylene-propylene-diene copolymers.

[0078] Polyolefin resins have excellent chemical resistance against various chemicals. Furthermore, polyolefin resins have good tracking resistance due to their hydrocarbon chain structure. Therefore, polyolefin resins contribute to improving the chemical resistance and tracking resistance of the three-dimensional molded insulator 1.

[0079] Of these, polypropylene resin is preferably used, which particularly improves the chemical resistance and tracking resistance of the three-dimensionally molded insulator 1.

[0080] 3.2.2. Polyamide resin Examples of polyamide resins include polycaproamide (polyamide 6), polytetramethylene adipamide (polyamide 46), polyhexamethylene adipamide (polyamide 66), polyhexamethylene sebacamide (polyamide 610), polyhexamethylene dodecamide (polyamide 612), polyundecamethylene adipamide (polyamide 116), polyundecane amide (polyamide 11), polydodecanamide (polyamide 12), polytrimethylhexamethylene terephthalamide (polyamide TMHT), polyhexamethylene terephthalamide (polyamide 6T), polyhexamethylene isophthalamide (polyamide 6I), and polyhexamethylene sebacamide (polyamide 610). Examples of suitable polyamides include ethylene terephthalic / isophthalamide (polyamide 6T / 6I), polybis(4-aminocyclohexyl)methanedodecamide (polyamide PACM12), polybis(3-methyl-4-aminocyclohexyl)methanedodecamide (polyamide dimethyl PACM12), polymetaxylylene adipamide (polyamide MXD6), polynonamethylene terephthalamide (polyamide 9T), polydecamethylene terephthalamide (polyamide 10T), polyundecamethylene terephthalamide (polyamide 11T), and polyundecamethylene hexahydroterephthalamide (polyamide 11T(H)), and copolymers or mixtures thereof may also be used.

[0081] The polyamide resin can be obtained by polymerizing or copolymerizing nylon salts made from diamines and dicarboxylic acids using known methods such as melt polymerization, solution polymerization, and solid-state polymerization. By using polyamide resins as the first resin and the second resin, the tracking resistance of the three-dimensionally molded insulator 1 can be further improved.

[0082] The diamine may be an aliphatic diamine, but an alicyclic diamine or aromatic diamine is preferably used, and an alicyclic diamine is more preferably used. By using these, a polyamide resin having a cyclic structure such as an aromatic ring structure or an alicyclic structure can be prepared. Such a polyamide resin contributes to improving the heat resistance of the three-dimensionally molded insulator 1. Furthermore, the alicyclic diamine in particular contributes to improving the tracking resistance of the three-dimensionally molded insulator 1.

[0083] Examples of alicyclic diamines include 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, 1,3-cyclohexanedimethylamine, 1,4-cyclohexanedimethylamine, bis(4-aminocyclohexyl)methane, bis(4-aminocyclohexyl)propane, bis(3-methyl-4-aminocyclohexyl)methane, bis(3-methyl-4-aminocyclohexyl)propane, 5-amino-2,2,4-trimethyl-1-cyclopentanemethylamine, 5-amino-1,3,3-trimethylcyclohexanemethylamine (isophoronediamine), bis(aminopropyl)piperazine, bis(aminoethyl)piperazine, norbornanedimethylamine, and tricyclodecanedimethylamine, and one or more of these may be used.

[0084] Examples of aromatic diamines include m-xylylenediamine and p-xylylenediamine.

[0085] The dicarboxylic acid may be an alicyclic dicarboxylic acid or an aromatic dicarboxylic acid, but an aliphatic dicarboxylic acid is preferred. This allows the preparation of a polyamide resin with a hydrocarbon chain structure. Such a polyamide resin contributes to improving the tracking resistance of the three-dimensionally molded insulator 1.

[0086] Examples of dicarboxylic acids include aliphatic dicarboxylic acids such as adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, octadecanedioic acid, and eicosanedioic acid; alicyclic dicarboxylic acids such as 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, dicyclohexanemethane-4,4'-dicarboxylic acid, and norbornanedicarboxylic acid; and aromatic dicarboxylic acids such as isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid. One or more of these may be used.

[0087] The polyamide resin preferably used is polyamide 6T, polyamide PACM12, polyamide dimethyl PACM12, polyamide MXD6, polyamide 9T, polyamide 10T, polyamide 11T, or polyamide 11T(H), and more preferably polyamide PACM12 or polyamide dimethyl PACM12. These resins have both a cyclic structure such as an aromatic ring structure or an alicyclic structure, and a structure derived from an aliphatic monomer, and therefore contribute to improving both the heat resistance and tracking resistance of the three-dimensionally molded insulator 1. Polyamide PACM12 contains a structural unit represented by the following formula (2).

[0088] [ka]

[0089] The polyamide PACM12 is synthesized from bis(4-aminocyclohexyl)methane (PACM) and dodecanedioic acid. Polyamide dimethyl PACM12 contains a structural unit represented by the following formula (3).

[0090] [ka]

[0091] The polyamide dimethyl PACM12 is synthesized using bis(3-methyl-4-aminocyclohexyl)methane (MACM) and dodecanedioic acid as raw materials.

[0092] 3.2.3. Aliphatic polycarbonate resin Examples of aliphatic polycarbonate resins include those containing an aliphatic carbonate unit having a carbon number of 2 to 12. Specific examples include polyethylene carbonate, polypropylene carbonate, polytrimethylene carbonate, polytetramethylene carbonate, polypentamethylene carbonate, polyhexamethylene carbonate, polyheptamethylene carbonate, polyoctamethylene carbonate, polynonamemethylene carbonate, polydecamethylene carbonate, polyoxydiethylene carbonate, poly-3,6-dioxyoctane carbonate, poly-3,6,9-trioxyundecane carbonate, polyoxydipropylene carbonate, polycyclopentene carbonate, and polycyclohexene carbonate.

[0093] The aliphatic polycarbonate resin may also be a resin containing an aliphatic carbonate unit containing a diol residue represented by the following formula (4).

[0094] [ka]

[0095] (In formula (4), R 5 ~R 8 are each independently a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group.

[0096] The aliphatic polycarbonate resin preferably contains 30 mol % to 100 mol %, and more preferably 50 mol % to 90 mol %, of all structural units of the aliphatic carbonate unit containing the diol residue represented by the above formula (4).

[0097] The diol residue represented by the formula (4) has a structure in which two tetrahydrofuran rings are fused together. By including such a structure in the structural unit, the glass transition temperature (Tg) of the aliphatic polycarbonate resin can be increased. As a result, a three-dimensional molded insulator 1 having excellent heat resistance and tracking resistance can be obtained.

[0098] Examples of diols constituting the diol residue represented by the above formula (4) include isosorbide, isomannide, isoidide, etc. These carbohydrate-derived diols are useful in that they are substances that can also be obtained from natural biomass.

[0099] 3.2.4. Aromatic polycarbonate resin Aromatic polycarbonate resins can be obtained by the phosgene method, which involves reacting various dihydroxydiaryl compounds with phosgene, the transesterification method, which involves reacting a dihydroxydiaryl compound with a carbonate ester such as diphenyl carbonate, the ring-opening polymerization method of a cyclic carbonate compound, the interfacial polycondensation method, etc. Such aromatic polycarbonate resins impart excellent heat resistance and flame retardancy, which are derived from the aromatic ring structure, to the three-dimensional molded insulator 1.

[0100] Dihydroxydiaryl compounds include, in addition to bisphenol A, bis(hydroxyaryl)alkanes such as bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane, bis(4-hydroxyphenyl)phenylmethane, 2,2-bis(4-hydroxyphenyl-3-methylphenyl)propane, and 1,1-bis(4-hydroxy-3-tert-butylphenyl)propane; and bis(hydroxyaryl)cycloalkanes such as 1,1-bis(4-hydroxyphenyl)cyclopentane and 1,1-bis(4-hydroxyphenyl)cyclohexane. dihydroxydiaryl ethers such as 4,4'-dihydroxydiphenyl ether and 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether, dihydroxydiaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide, dihydroxydiaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone, dihydroxydiaryl sulfones such as 4,4'-dihydroxydiphenyl sulfone and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone, etc. These may be used alone or in combination of two or more.

[0101] The aromatic polycarbonate resin particularly includes those having a structural unit represented by the following formula (1).

[0102] [ka] (In formula (1), R 1 and R 2 are independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms, an aryl group having 6 to 12 carbon atoms, or a halogen atom. m and n are independently an integer of 0 to 4. X is a direct bond, O, S, SO, SO2, CR 3 R 4(R 3 and R 4 are independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and may be the same or different from each other.), an alkylene group having 2 to 10 carbon atoms, a polydimethylsiloxane group, or C(CF3)2.

[0103] The aromatic polycarbonate resin having the structural unit represented by the above formula (1) imparts particularly excellent heat resistance and flame retardancy to the three-dimensionally molded insulator 1.

[0104] Of all the structural units constituting the aromatic polycarbonate resin, the proportion of the structural units represented by the above formula (1) is preferably 55 mol % or more, more preferably 70 mol % or more, and even more preferably 80 mol % or more.

[0105] In addition, from the viewpoint of ease of acquisition and cost, R 1 and R 2 are each preferably a hydrogen atom, and X is preferably CR 3 R 4 and R 3 and R 4 are preferably each a methyl group or a hydrogen atom.

[0106] The aromatic polycarbonate resin is preferably a polycarbonate resin having structural units derived from bisphenol A (2,2-bis(4-hydroxyphenyl)propane), which can further improve the flame retardancy and heat resistance of the three-dimensional molded insulator 1.

[0107] The viscosity average molecular weight (M) of the aromatic polycarbonate resin is not particularly limited, but is preferably 5,000 or more and 100,000 or less, more preferably 12,000 or more and 35,000 or less, even more preferably 15,000 or more and 30,000 or less, and particularly preferably 18,000 or more and 28,000 or less.

[0108] The viscosity average molecular weight (M) is calculated from the viscosity (η) of the methylene chloride solution of the resin, η = kM α The viscosity is calculated using the formula below. k and α are constants specific to polymers. Viscosity is measured using an Ubbelohde viscometer at 20°C.

[0109] The aromatic polycarbonate resin may also be a blend of a resin with a high viscosity average molecular weight (high viscosity resin) and a resin with a low viscosity average molecular weight (low viscosity resin), thereby providing a three-dimensionally molded insulator 1 with excellent moldability without impairing the heat resistance and flame retardancy inherent to the aromatic polycarbonate resin.

[0110] The difference between the viscosity average molecular weight of the high-viscosity resin and the viscosity average molecular weight of the low-viscosity resin is not particularly limited, but is preferably 3,000 to 20,000, and more preferably 5,000 to 10,000. This allows for the production of a three-dimensionally molded insulator 1 with particularly good moldability.

[0111] When the blending amount of the high-viscosity resin is M1 and the blending amount of the low-viscosity resin is M2, the blending ratio M1 / M2 is preferably 0.5 to 8.0 in mass ratio, more preferably 0.8 to 6.0 in mass ratio, and even more preferably 0.9 to 5.0 in mass ratio, thereby obtaining a three-dimensional molded insulator 1 with particularly good moldability.

[0112] The glass transition temperature Tg of the aromatic polycarbonate resin is preferably 130°C or higher and lower than 160°C, and more preferably 140°C or higher and 155°C or lower. If the glass transition temperature Tg of the aromatic polycarbonate resin is within the above range, the heat resistance and flame retardancy of the three-dimensionally molded insulator 1 can be sufficiently improved. The glass transition temperature Tg of the aromatic polycarbonate resin is measured by a differential scanning calorimeter (DSC) method. The heating rate in the DSC method is 10°C / min.

[0113] The content of the aromatic polycarbonate resin in the three-dimensionally molded insulator 1 is not particularly limited, but is preferably 70% by mass or more, and more preferably 80% by mass or more.

[0114] The melt volume rate (MVR) of aromatic polycarbonate resin at 300°C and a load of 1.2 kg is 5 cm 3 / 10min] or more 20[cm 3 / 10min] or less, and 8 [cm 3 / 10min] or more 15[cm 3 / 10 min or less is more preferable. This improves the moldability of the three-dimensionally molded insulator 1 in secondary processing, particularly in vacuum molding, to prevent defects such as distortion. If the melt volume rate is below the lower limit, the flowability may be insufficient, resulting in reduced moldability. On the other hand, if the melt volume rate is above the upper limit, the impact resistance of the molded body may be reduced. The melt volume rate is measured in accordance with the test method specified in JIS K 7210:2014.

[0115] The aromatic polycarbonate resin may be a resin containing carbonate units (bisphenolisophorone carbonate units) represented by the following formula (5). Such aromatic polycarbonate resins have higher heat resistance than aromatic polycarbonate resins containing carbonate units represented by the above formula (1). Hereinafter, polycarbonate resins containing bisphenolisophorone carbonate units may be referred to as "heat-resistant polycarbonate resins."

[0116] [ka]

[0117] In formula (5), R a and R b are each independently an alkyl group having 1 to 12 carbon atoms, and R g is an alkyl group having 1 to 12 carbon atoms, p and q each independently represent 0 to 4, and t represents 0 to 10.

[0118] In addition, each R a and R b Preferably, at least one of is positioned meta to the cyclohexylidene bridging group.

[0119] Also, R a and R b are each independently an alkyl group having 1 to 4 carbon atoms, and R g is an alkyl group having 1 to 4 carbon atoms, p and q are each 0 or 1, and t may be 0 to 5.

[0120] Furthermore, R a , R b , and R g are each a methyl group, p and q are each 0 or 1, and t is 0 or 3, preferably 0.

[0121] A specific example of such a heat-resistant polycarbonate resin is a resin containing carbonate units (bisphenol A carbonate units) derived from bisphenol A (2,2-bis(4-hydroxyphenyl)propane) and carbonate units (bisphenol isophorone carbonate units) represented by formula (5). In this case, p and q in the bisphenol isophorone carbonate units are each 0, and each R g is preferably a methyl group, and t is preferably 3. In this case, the bisphenol isophorone carbonate unit is particularly a carbonate unit containing a structure derived from bisphenol TMC (1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane).

[0122] Such bisphenol isophorone carbonate units contain both an aromatic ring structure and an alicyclic structure, and therefore contribute particularly to improving both the heat resistance (flame retardancy) and tracking resistance of the three-dimensional molded insulator 1.

[0123] Of all structural units constituting the heat-resistant polycarbonate resin, the proportion of bisphenol isophorone carbonate units is preferably 30% by mass or more, more preferably 35% by mass to 60% by mass or less, and even more preferably 40% by mass to 50% by mass or less. This contributes to improving both the heat resistance (flame retardancy) and tracking resistance of the three-dimensionally molded insulator 1. It also improves the moldability of the heat-resistant polycarbonate resin.

[0124] If the proportion of bisphenol isophorone carbonate units is below the lower limit, there is a risk of a decrease in at least one of the heat resistance (flame retardancy) and tracking resistance of the three-dimensionally molded insulator 1. On the other hand, if the proportion of bisphenol isophorone carbonate units is above the upper limit, there is a risk of a decrease in the moldability of the heat-resistant polycarbonate resin, and a decrease in the dimensional accuracy of the three-dimensionally molded insulator 1.

[0125] The glass transition temperature Tg of the heat-resistant polycarbonate resin is preferably 160° C. or higher and 230° C. or lower, and more preferably 165° C. or higher and 220° C. or lower. When the glass transition temperature Tg of the heat-resistant polycarbonate resin is within the above range, the heat resistance of the three-dimensionally molded insulator 1 can be particularly improved. As a result, even if creeping discharge occurs in the three-dimensionally molded insulator 1, coloring due to carbonization can be particularly suppressed, thereby particularly suppressing the occurrence of poor appearance and the deterioration of insulating properties due to carbonization.

[0126] If the glass transition temperature Tg is below the lower limit, there is a risk that poor appearance or carbonization due to creeping discharge may occur. On the other hand, if the glass transition temperature Tg is above the upper limit, there is a risk that the molding temperature of the heat-resistant polycarbonate resin may become too high, making molding defects more likely to occur. Furthermore, when the heat-resistant polycarbonate resin is alloyed with a compatible resin, there is a risk that thermal degradation of the compatible resin may occur depending on the heat resistance of the compatible resin.

[0127] 3.2.5. Polymer alloys The constituent material of the three-dimensionally molded insulator 1 may include a polymer alloy formed by alloying an aromatic polycarbonate resin with a compatible resin. A polymer alloy refers to a single-phase material or a stable multi-phase material formed by mixing multiple types of polymers, preferably a single-phase material. As used herein, "alloying" refers to the preparation of such a single-phase or multi-phase material by kneading or otherwise mixing raw materials containing multiple types of polymers. In particular, alloying an aromatic polycarbonate resin with a compatible resin provides a three-dimensionally molded insulator 1 that combines the heat resistance inherent in the aromatic polycarbonate resin with other properties inherent in the compatible resin.

[0128] The compatible resin preferably includes the aforementioned polyolefin resin, polyamide resin, aliphatic polycarbonate resin, and aromatic polycarbonate resin (heat-resistant polycarbonate resin) containing the carbonate unit represented by formula (5). In this case, the aromatic polycarbonate resin alloyed with these compatible resins preferably has a resin having the structural unit represented by formula (1). In such a combination, the compatible resin has a higher tracking resistance (comparative tracking index CTI) than the aromatic polycarbonate resin having the structural unit represented by formula (1). This allows for the production of a three-dimensional molded insulator 1 that has both heat resistance and tracking resistance.

[0129] The proportion of the compatible resin in the polymer alloy is not particularly limited, but is preferably 5% by mass to 80% by mass, more preferably 10% by mass to 75% by mass, even more preferably 20% by mass to 70% by mass, and particularly preferably 40% by mass to 65% by mass. This configuration makes it possible to realize a polymer alloy that has a good balance between the properties of the aromatic polycarbonate resin having the structural unit represented by formula (1), such as heat resistance and flame retardancy, and the properties of the compatible resin.

[0130] The comparative tracking index CTI of the compatible resin is preferably 400 V or more, and more preferably 600 V or more, thereby providing a three-dimensional molded insulator 1 with particularly good tracking resistance.

[0131] Furthermore, the comparative tracking index CTI of the compatible resin is preferably at least 50 V higher than the comparative tracking index CTI of the aromatic polycarbonate resin, and more preferably at least 100 V higher, thereby providing a three-dimensional molded insulator 1 that better balances flame retardancy and tracking resistance.

[0132] The glass transition temperature Tg of the compatible resin is preferably 125° C. or higher, and more preferably 130° C. or higher and 230° C. or lower. This provides heat resistance to the compatible resin, making it easier to suppress coloration due to carbonization even if creeping discharge occurs in the three-dimensionally molded insulator 1. As a result, the occurrence of poor appearance in the three-dimensionally molded insulator 1 and the deterioration of insulating properties due to carbonization can be suppressed.

[0133] Furthermore, the compatible resin preferably has an aromatic monomer molar fraction of 90% or less, more preferably 70% or less, and even more preferably 50% or less, of the total monomer components. Such a compatible resin has a relatively high ratio of structures derived from aliphatic monomers. This allows the three-dimensionally molded insulator 1 to have good tracking resistance. This allows the three-dimensionally molded insulator 1 to have better flame retardancy and tracking resistance. Furthermore, even if creeping discharge occurs in the three-dimensionally molded insulator 1, coloring due to carbonization can be easily suppressed. As a result, the occurrence of poor appearance in the three-dimensionally molded insulator 1 and the deterioration of insulating properties due to carbonization can be suppressed. Note that the aromatic monomer refers to a monomer (aromatic compound) containing an aromatic ring structure.

[0134] The polymer alloy may contain resins other than the above components, that is, the polymer alloy may be an alloy of three or more resins.

[0135] An example of a method for preparing a polymer alloy will be described. First, the raw materials are premixed and melted and kneaded using a batch kneader, twin-screw extruder, or the like. This mechanically stirs the raw materials, resulting in a kneaded product containing a polymer alloy. The kneading and melting conditions are appropriately set depending on the type and blending ratio of the raw materials, and examples include a temperature of 200 to 250°C, a screw rotation speed of 300 to 1000 rpm, and a kneading time of about 3 to 20 minutes. Next, the kneaded product is pelletized as necessary.

[0136] Furthermore, a compatibilizer may be added to the raw materials as needed, which can further increase the compatibility of the resins to be alloyed.

[0137] The amount of the compatibilizer added is preferably 2 parts by mass or more and 30 parts by mass or less, and more preferably 5 parts by mass or more and 20 parts by mass or less, relative to 100 parts by mass of the resin.

[0138] Additives The three-dimensionally molded insulator 1 may contain any additives. Examples of additives include flame retardants, colorants, stabilizers, lubricants, processing aids, antistatic agents, antioxidants, neutralizing agents, UV absorbers, dispersants, thickeners, mold release agents, fillers, flow improvers, plasticizers, and antibacterial agents. The three-dimensionally molded insulator 1 may contain one type of additive, or two or more types in any combination.

[0139] Among these, the flame retardant enhances the flame retardancy of the three-dimensionally molded insulator 1 . Examples of the flame retardant include inorganic phosphorus-based flame retardants such as halogen-based flame retardants, red phosphorus and polyphosphate-based flame retardants such as ammonium polyphosphate, organic phosphorus-based flame retardants such as triaryl phosphate ester compounds, metal hydroxide-based compounds, antimony oxide-based compounds, nitrogen-containing compounds, etc. Furthermore, the flame retardant may be a combination of two or more of these.

[0140] Among these, phosphorus-based flame retardants or nitrogen-containing compounds are preferably used as the flame retardant, and nitrogen-containing compounds are more preferably used. When the flame retardant contains a nitrogen-containing compound, the flame retardancy of the three-dimensional molded insulator 1 can be further improved. Furthermore, since the nitrogen-containing compound does not contain halogen atoms, a so-called halogen-free and fluorine-free three-dimensional molded insulator 1 can be realized.

[0141] Examples of the nitrogen-containing compound include compounds having a triazine skeleton. Examples of compounds having a triazine skeleton include melamine, melamine derivatives such as butylmelamine, trimethylolmelamine, hexamethylolmelamine, hexamethoxymethylmelamine, and melamine phosphate, cyanuric acid, cyanuric acid derivatives such as methyl cyanurate, diethyl cyanurate, trimethyl cyanurate, and triethyl cyanurate, isocyanuric acid, isocyanuric acid derivatives such as methyl isocyanurate, N,N'-diethyl isocyanurate, trismethyl isocyanurate, trisethyl isocyanurate, bis(2-carboxyethyl) isocyanurate, 1,3,5-tris(2-carboxyethyl) isocyanurate, and tris(2,3-epoxypropyl) isocyanurate, melamine cyanurate, and melamine isocyanurate. These compounds can be used alone or in combination of two or more.

[0142] Among these, the compound having a triazine skeleton is preferably one or more melamine-based compounds selected from the group consisting of melamine, melamine cyanurate, melamine isocyanurate, and derivatives thereof, and more preferably melamine cyanurate, which can particularly enhance the flame retardancy of the three-dimensional molded insulator 1.

[0143] The amount of flame retardant added is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, and even more preferably 3 to 10 parts by mass, per 100 parts by mass of resin. By keeping the amount of flame retardant added within this range, the effect of enhancing flame retardancy is fully exerted, and side effects such as a decrease in mechanical properties due to an excess of flame retardant can be suppressed.

[0144] The flame retardant is, for example, in particulate form. In this case, the average particle size of the flame retardant is preferably 0.01 μm to 10 μm, more preferably 0.05 μm to 5 μm, and even more preferably 0.2 μm to 2 μm. When the average particle size of the flame retardant is within the above range, the dispersibility of the flame retardant is particularly good, thereby particularly improving the flame retardancy of the three-dimensionally molded insulator 1. The average particle size of the flame retardant is the particle size at which the cumulative total from the small diameter side in the volume-based particle size distribution measured using a laser diffraction particle size distribution analyzer is 50%.

[0145] Furthermore, the total amount of additives added is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 0.3 parts by mass or more and 5 parts by mass or less, and even more preferably 0.5 parts by mass or more and 3 parts by mass or less, relative to 100 parts by mass of resin.

[0146] 3.3.Multilayer structure Next, a three-dimensionally shaped insulator 1 according to a modified example will be described. FIG. 7 is a cross-sectional view showing a three-dimensionally shaped insulator 1 according to a modified example.

[0147] Below, we will explain the three-dimensionally shaped insulator 1 related to the modified example, but in the following explanation, we will focus on the differences from the three-dimensionally shaped insulator 1 shown in Figure 1, and omit explanations of similar points.

[0148] The three-dimensionally shaped insulator 1 shown in FIG. 7 is similar to the three-dimensionally shaped insulator 1 shown in FIG. 1, except that it has a multi-layer structure.

[0149] The three-dimensionally shaped insulator 1 shown in FIG. 7 has a first layer 101, an intermediate layer 103, and a second layer 102 laminated in this order from the bottom. The intermediate layer 103 has a lower surface (first surface) and an upper surface (second surface) that are opposite each other, and preferably contains an aromatic polycarbonate resin and a flame retardant. The first layer 101 is laminated on the lower surface (first surface) of the intermediate layer 103 and contains a first resin. The second layer 102 is laminated on the upper surface (second surface) of the intermediate layer 103 and contains a second resin. The first resin and the second resin are preferably materials with higher tracking resistance than the aromatic polycarbonate resin contained in the intermediate layer 103.

[0150] According to this configuration, the aromatic polycarbonate resin is a polycarbonate resin containing an aromatic ring structure in the main chain, and the high proportion of the aromatic ring structure imparts good heat resistance to the intermediate layer 103. The intermediate layer 103 also contains a flame retardant. These properties contribute to the intermediate layer 103 having good flame retardancy.

[0151] Furthermore, the intermediate layer 103 is sandwiched between the first layer 101 and the second layer 102. Therefore, if a creeping discharge occurs in the three-dimensionally molded insulator 1, the intermediate layer 103 is prevented from being directly exposed to an arc discharge or the like. By using a material with higher tracking resistance than aromatic polycarbonate resin as the resin contained in the first layer 101 and the second layer 102, the three-dimensionally molded insulator 1 is endowed with good tracking resistance. Therefore, the three-dimensionally molded insulator 1 has excellent flame retardancy and tracking resistance.

[0152] Furthermore, with this configuration, one of the effects of the multilayer structure is improved pinhole resistance, which can further improve the insulation properties, flame retardancy, and tracking resistance of the three-dimensional molded insulator 1.

[0153] The comparative tracking index CTI of each of the first resin and the second resin is preferably at least 400 V, and more preferably at least 600 V. This allows the first resin and the second resin to have particularly good tracking resistance.

[0154] Furthermore, the comparative tracking index CTI of each of the first resin and the second resin is preferably at least 50 V higher than the comparative tracking index CTI of the aromatic polycarbonate resin, and more preferably at least 100 V higher. This makes it possible to obtain a three-dimensional molded insulator 1 that better balances flame retardancy and tracking resistance.

[0155] The glass transition temperature Tg of each of the first resin and the second resin is preferably 125°C or higher, and more preferably 130°C or higher and lower than 200°C. This provides heat resistance to the first resin and the second resin, making it easier to suppress coloration due to carbonization even if creeping discharge occurs in the first layer 101 and the second layer 102. As a result, it is possible to suppress the occurrence of poor appearance in the first layer 101 and the second layer 102 and the deterioration of insulation due to carbonization. The glass transition temperature Tg of each of the first resin and the second resin is measured by a differential scanning calorimeter (DSC) method. The heating rate in the DSC method is 10°C / min.

[0156] The melt volume rate (MVR) of the first and second resins at 300°C and a load of 1.2 kg is 5 cm 3 / 10min] or more 30[cm 3 / 10min] or less, and 8 [cm 3 / 10min] or more 20[cm 3 / 10 min or less is more preferable. This improves the moldability of the three-dimensionally molded insulator 1 in secondary processing, particularly in vacuum molding, to prevent defects such as distortion. If the melt volume rate is below the lower limit, the flowability may be insufficient, resulting in reduced moldability. On the other hand, if the melt volume rate is above the upper limit, the impact resistance of the molded body may be reduced. The melt volume rate is measured in accordance with the test method specified in JIS K 7210:2014.

[0157] Furthermore, the first resin and the second resin preferably have an aromatic monomer molar fraction of 90% or less, more preferably 70% or less, and even more preferably 50% or less, of the total monomer components. Such first resins and second resins have a relatively high ratio of structures derived from aliphatic monomers. This allows the first resin and the second resin to have good tracking resistance. This allows the first resin and the second resin to have better flame retardancy and tracking resistance. Furthermore, even if creeping discharge occurs in the three-dimensionally molded insulator 1, coloring due to carbonization can be easily suppressed. As a result, the occurrence of poor appearance in the three-dimensionally molded insulator 1 and the deterioration of insulating properties due to carbonization can be suppressed. The aromatic monomer refers to a monomer (aromatic compound) containing an aromatic ring structure.

[0158] The content of the first resin in the first layer 101 and the content of the second resin in the second layer 102 are preferably 70% by mass or more, and more preferably 80% by mass or more. The first resin and the second resin may be the resin materials described above.

[0159] Here, the tracking resistance and glass transition temperature (Tg) of resins (compounds) that can be used for the three-dimensionally molded insulator 1 according to this embodiment are exemplified. Table 1 below lists the CTI value, which indicates tracking resistance, and the glass transition temperature (Tg) for various resins that can be used as the resin materials (including the first resin and the second resin) and the aromatic polycarbonate resin. For the aromatic polycarbonate resin, the viscosity average molecular weight is also listed.

[0160] [Table 1]

[0161] As shown in Table 1, aromatic polycarbonate resins tend to have slightly lower tracking resistance than other resins. For this reason, using these resins in combination with aromatic polycarbonate resins is useful from the perspective of achieving the best possible properties of both resins.

[0162] Examples of methods for manufacturing the three-dimensionally molded insulator 1 shown in FIG. 7 include co-extrusion, dry lamination, extrusion lamination, and hot melt.

[0163] 3.4.Characteristics of Three-Dimensional Molded Insulators Next, the characteristics of the three-dimensionally shaped insulator 1 according to the embodiment will be described.

[0164] 3.4.1. Tracking resistance The tracking resistance of the three-dimensionally shaped insulator 1 according to the embodiment can be quantified by the comparative tracking index CTI, which is an index of tracking resistance measured in accordance with ASTM D3638.

[0165] The comparative tracking index CTI (CTI value) of the three-dimensionally molded insulator 1 according to the embodiment is preferably 600 V or more. If the CTI value is within the above range, the rank PLC, which indicates tracking resistance, will be the highest rank of 0. Therefore, it can be said that the three-dimensionally molded insulator 1 having a CTI value within the above range has particularly good tracking resistance.

[0166] The measurement method specified in IEC 60112, 3rd Edition, measures the CTI value using a 0.1% by mass aqueous solution of ammonium chloride and a platinum electrode. More specifically, the ammonium chloride aqueous solution is dropped a specified number of times (50 drops) and the voltage at which none of the test pieces (n=5) breaks down is determined, and this is taken as the CTI value.

[0167] The test piece used is a three-dimensionally molded insulator 1 having a thickness of 3 mm or more. The test piece may be a stack of a plurality of three-dimensionally molded insulators 1.

[0168] The comparative tracking indexes CTI of the first and second resins and the aromatic polycarbonate resin are measured in the same manner as above. In this case, test pieces are made of sheets of these resins extruded to a thickness of 3 mm or more.

[0169] 3.4.2.Flame retardancy The flame retardancy of the three-dimensionally molded insulator 1 according to the embodiment can be quantified by the flame retardancy rank determined in accordance with the UL94 standard (rank determined by UL94V test or UL94VTM test).

[0170] It is preferable that the flame retardancy of the three-dimensional molded insulator 1 of the embodiment is such that the UL94V test rank is V-0 for a test specimen thickness of 0.4 mm or more, or the UL94VTM test rank is VTM-0 for a test specimen thickness of 0.4 mm or more.

[0171] The three-dimensionally molded insulator 1 that satisfies such a judgment rank satisfies the highest rank in each test, and therefore can be said to have particularly good flame retardancy.

[0172] In the UL94V test, a vertical combustion test is conducted using a test piece measuring 125±5mm x 13.0±0.5mm and having a thickness of 0.4mm or more but less than 13mm.

[0173] The UL94VTM test is conducted when the test specimen is too thin to be subjected to the UL94V test. The UL94VTM test is a vertical flame test using a test specimen measuring 200mm x 50mm and 0.4mm to 0.25mm thick.

[0174] 3.4.3.Breakdown voltage The breakdown voltage of the three-dimensionally molded insulator 1 according to the embodiment is a breakdown voltage measured in accordance with the method for measuring breakdown strength (AC test) specified in JIS C 2318:2020.

[0175] The breakdown voltage of the three-dimensionally molded insulator 1 according to the embodiment is preferably 5 kV or more, more preferably 7 kV to 60 kV, and even more preferably 10 kV to 50 kV. A three-dimensionally molded insulator 1 satisfying such a breakdown voltage contributes to ensuring sufficient insulation even when the insulation clearance is short. Note that the breakdown voltage may exceed the upper limit, but is preferably equal to or less than the upper limit in order to minimize individual variations.

[0176] 4. Manufacturing method of three-dimensional molded insulator Next, a method for manufacturing the three-dimensionally shaped insulator 1 (a method for manufacturing a three-dimensionally shaped insulator according to the embodiment) will be described.

[0177] First, a flat thermoplastic insulating sheet is produced from raw materials containing the above-mentioned resin material by a method such as calendaring, extrusion, pressing, casting, etc. A thermoplastic insulating sheet having a multilayer structure is produced by the method described above.

[0178] Next, the thermoplastic insulating sheet is subjected to secondary processing including thermoforming, thereby forming the recesses 12. Thermoforming methods include vacuum forming, pressure forming, and vacuum pressure forming. This type of thermoforming results in a three-dimensionally formed insulator 1 with little variation in thickness due to shape and high shape accuracy. Furthermore, vacuum forming and vacuum pressure forming provide particularly high shape accuracy.

[0179] The heating temperature during thermoforming is not particularly limited, but is preferably 130° C. or higher and 260° C. or lower, and more preferably 140° C. or higher and 240° C. or lower. This makes it possible to obtain a three-dimensionally molded insulator 1 with particularly little variation in thickness and particularly high shape precision.

[0180] Furthermore, other secondary processes may be added before or after thermoforming, such as folding, punching, and the like.

[0181] 5. How to use three-dimensionally molded insulation Next, an example of use of the three-dimensionally molded insulator 1 will be described.

[0182] FIG. 8 is a cross-sectional view showing a control device 8 in which the three-dimensional molded insulator 1 according to the embodiment and a circuit board 9 are housed in a case 80. As shown in FIG.

[0183] 8 includes a circuit board 9, a three-dimensionally shaped insulator 1, and a case 80 that houses these. Note that the device that includes the circuit board 9 is not limited to the control device 8, and may be a device with any function.

[0184] The case 80 has a box-like shape with a bottom, a housing 81 with an open top, a lid 82 that closes the opening of the housing 81, and a heat dissipation sheet 85.

[0185] The housing 81 has a bottom that extends along the XY plane and a wall that rises upward from the outer edge of the bottom. A circuit board 9 is accommodated inside the housing 81. The circuit board 9 is fixed to the housing 81 with fixing screws 94 (not shown in FIG. 8). The circuit board 9 is also fixed in contact with a heat dissipation sheet 85.

[0186] The lid 82 only needs to close the opening of the housing 81, but it is preferable that the lid 82 seals the opening in a liquid-tight or air-tight manner, thereby stably protecting the circuit board 9 from the external environment.

[0187] Examples of materials for the housing 81 and the lid 82 include metal materials, ceramic materials, and resin materials. A composite material using two or more of these materials may also be used. Of these, metal materials are preferably used. Metal materials have excellent thermal conductivity and mechanical properties, making them useful as materials for the housing 81 and the lid 82. Furthermore, metal materials often have excellent electrical conductivity and magnetic permeability, making it possible to use the housing 81 and the lid 82 as electromagnetic shields or magnetic field shields.

[0188] Furthermore, when a metal material is used, there is a concern of short-circuiting between circuit board 9 and the metal material. In particular, short-circuiting is likely to occur between components protruding from the top surface of wiring board 90 and lid portion 82, so conventionally, it has been necessary to ensure a necessary spatial distance between them.

[0189] In contrast, this spatial distance can be reduced by using the three-dimensionally molded insulator 1. For example, the distance S3 between the power semiconductor element 91 and the lid 82 and the distance S4 between the bus bar 92 and the lid 82 shown in Fig. 8 can be reduced. This allows the control device 8 to be made thinner and more compact.

[0190] The distances S3 and S4 vary depending on the voltage applied to the components, but as an example, they are preferably 10 mm or less, and more preferably 5 mm or less, which allows the control device 8 to be made even thinner and more compact.

[0191] Furthermore, by using the three-dimensionally molded insulator 1, a sufficient space SP can be secured between the flat portion 11 of the three-dimensionally molded insulator 1 and the lid portion 82. This space SP ensures insulation from the power semiconductor elements 91 and the bus bars 92, so that even if the space SP is used to house another object, for example, the occurrence of a short circuit can be suppressed.

[0192] FIG. 9 is a cross-sectional view showing a modified example of the control device 8 of FIG. The case 80 shown in FIG. 9 is similar to the case 80 shown in FIG. 8 except that a partition wall 83 is added. The partition wall 83 is installed inside the housing 81 and separates the interior space of the housing 81 into upper and lower spaces. The space below the partition wall 83 contains a circuit board 9 and a three-dimensionally molded insulator 1. The space above the partition wall 83 contains a circuit board 7 separate from the circuit board 9. The circuit board 7 includes a wiring board 71 and a semiconductor element 72. By containing such a circuit board 7 in the same space as the circuit board 9, the height of the case 80 can be minimized while increasing the functionality of the control device 8.

[0193] 9, another flat insulating sheet 2 is provided on the underside of the lid 82. This flat insulating sheet 2 has a flat plate shape. By providing such a flat insulating sheet 2, the spatial distance required between the circuit board 7 and the lid 82 can be reduced. This allows the height of the case 80 to be further reduced.

[0194] As described above, by using the three-dimensionally shaped insulator 1 and the flat insulating sheet 2 in combination, it is possible to achieve both high functionality and miniaturization of the control device 8.

[0195] 6. Effects of the above embodiment The three-dimensionally shaped insulator 1 according to the embodiment is a three-dimensionally shaped insulator that is placed over a component to which voltage is applied. Such a three-dimensionally shaped insulator 1 is molded into a shape having a recess 12. The recess 12 includes a bottom 12a and a wall 12b provided at an end of the bottom 12a. The three-dimensionally shaped insulator 1 is used with a component inserted into the recess 12.

[0196] With this configuration, by providing recesses 12 in accordance with the components to which voltage is applied, it is possible to reduce the dead space around the components. This allows for more efficient use of the space in which the components are housed. As a result, it is possible to miniaturize the equipment in which the components are mounted.

[0197] It may also be used by covering a circuit board 9 that includes components and a wiring board 90 (substrate) on which the components are mounted. In this case, the three-dimensionally shaped insulator 1 is preferably molded into a shape having a recess 12 and a flat portion 11 connected to the recess 12.

[0198] According to this configuration, by providing recesses 12 to fit the components mounted on wiring board 90, it is possible to reduce the dead space that occurs between circuit board 9 and three-dimensionally molded insulator 1 (around the components). This allows for effective use of the space in which circuit board 9 is housed. As a result, it is possible to reduce the size of the device in which circuit board 9 is mounted.

[0199] Moreover, the three-dimensionally shaped insulator 1 according to the embodiment has through holes 13 that penetrate the flat portion 11 in the thickness direction.

[0200] According to this configuration, when a fixing screw 94 or the like is provided in alignment with the through hole 13, the fixing screw 94 can be rotated even when the three-dimensionally shaped insulator 1 is placed over the circuit board 9. Therefore, with the three-dimensionally shaped insulator 1 placed over the circuit board 9, the circuit board 9 can be screwed to a case or the like, improving assembly workability.

[0201] Furthermore, it is preferable that the thickness t12b of the wall portion 12b is 20% or more and 95% or less of the thickness t11 of the flat portion 11.

[0202] With this configuration, the wall portion 12b has sufficient rigidity to support the shape of the recessed portion 12 and can contribute to further reducing the dead space on the sides of the recessed portion 12.

[0203] Furthermore, the thickness t11 of the flat portion 11 is preferably 0.05 mm or more and 1.00 mm or less.

[0204] With this configuration, a three-dimensional molded insulator 1 can be obtained that is excellent in flame retardancy, tracking resistance, and insulation, and is relatively easy to manufacture.

[0205] The three-dimensionally shaped insulator 1 according to the embodiment may also contain a flame retardant. With this configuration, a three-dimensional molded insulator 1 having excellent flame retardancy can be obtained.

[0206] Moreover, the three-dimensionally shaped insulator 1 according to the embodiment is preferably made primarily of a thermoplastic resin.

[0207] A sheet made primarily of a thermoplastic resin can be plastically deformed by heat, making it suitable for secondary processing. This allows it to be manufactured by thermoforming, resulting in a three-dimensionally shaped insulator 1 that is easy to manufacture.

[0208] The thermoplastic resin may also contain an aromatic polycarbonate resin. With this configuration, the three-dimensional molded insulator 1 can be obtained with excellent heat resistance and flame retardancy due to the aromatic ring structure.

[0209] Furthermore, the three-dimensionally shaped insulator 1 according to the embodiment preferably has a comparative tracking index CTI, which is an index of tracking resistance measured in accordance with ASTM D3638, of 600V or more.

[0210] With this configuration, a three-dimensionally molded insulator 1 having particularly good tracking resistance can be obtained.

[0211] Furthermore, the three-dimensionally molded insulator 1 according to the embodiment preferably has a flame retardancy rank of V-0 or VTM-0 when judged in accordance with the UL94 standard for a test piece having a thickness of 0.4 mm or more. With this configuration, a three-dimensional molded insulator 1 with particularly good flame retardancy can be obtained.

[0212] Furthermore, the manufacturing method of the three-dimensional molded insulator according to the embodiment is a manufacturing method of the three-dimensional molded insulator 1, in which a flat thermoplastic insulating sheet is subjected to secondary processing including thermoforming to form the recess 12. With this configuration, it is possible to manufacture a three-dimensionally molded insulator with high shape accuracy.

[0213] The thermoforming is preferably vacuum forming or vacuum / pressure forming. With this configuration, it is possible to manufacture a three-dimensionally molded insulator with particularly high shape accuracy.

[0214] Although the three-dimensionally shaped insulator and the method for manufacturing the three-dimensionally shaped insulator of the present invention have been described above, the present invention is not limited to the above-described embodiment.

[0215] For example, the three-dimensionally shaped insulator of the present invention may contain additives other than those described in the above embodiment.

[0216] In addition, the three-dimensional molded insulator of the present invention may have a layer having any function added to the layer structure described in the above embodiment, such as an adhesive layer, a bonding layer, a protective layer, a release layer, etc.

[0217] Furthermore, the method for producing a three-dimensionally shaped insulator of the present invention may be such that any desired step is added to the above-described embodiment. [Explanation of symbols]

[0218] 1. Three-dimensional molded insulator 2 Flat insulating sheet 7 Circuit Board 8 Control Device 9 Circuit Board 11 Flat area 12 recess 13 Through hole 71 Wiring board 72 Semiconductor elements 80 cases 81 Housing 82 Lid 83 Bulkhead 85 Heat dissipation sheet 90 Wiring board 91 Power semiconductor elements 92 Busbar 93 Signal Connector 94 Fixing screw 101 1st layer 102 2nd layer 103 Middle Class 110 Flat surface 121 recess 122 recess 123 Recess 901 Insulation layer 902 Wiring layer 903 Through Wiring 904 Thermal via 921 Busbar 922 Busbar L1 spatial distance S1 separation distance S2 separation distance S3 separation distance S4 separation distance SP Space

Claims

1. A three-dimensionally shaped insulator that is placed over a component to which voltage is applied, The container is molded into a shape having a recess including a bottom and a wall portion provided at an end of the bottom, A three-dimensionally molded insulator characterized in that the component is inserted into the recess when used.

2. The component is used by being placed over a circuit board including the component and a board on which the component is mounted, The three-dimensionally molded insulator according to claim 1 , which is molded into a shape having the recess and a flat portion connected to the recess.

3. The three-dimensionally shaped insulator according to claim 2 , further comprising a through-hole penetrating the flat portion in the thickness direction.

4. 4. The three-dimensionally shaped insulator of claim 3, wherein the thickness of the wall portion is 20% to 95% of the thickness of the flat portion.

5. 5. The three-dimensionally molded insulator according to claim 3, wherein the thickness of the flat portion is 0.05 mm or more and 1.00 mm or less.

6. 5. The three-dimensionally shaped insulator of claim 1, further comprising a flame retardant.

7. 5. The three-dimensionally molded insulator according to claim 1, wherein the main material is a thermoplastic resin.

8. 8. The three-dimensionally shaped insulator of claim 7, wherein the thermoplastic resin comprises an aromatic polycarbonate resin.

9. 5. The three-dimensionally molded insulator according to claim 1, wherein a comparative tracking index (CTI), which is an index of tracking resistance measured in accordance with ASTM D3638, is 600 V or more.

10. 5. The three-dimensional molded insulator according to claim 1, wherein the flame retardancy measured in accordance with the UL94 standard is V-0 or VTM-0 for a test piece having a thickness of 0.4 mm or more.

11. A method for manufacturing the three-dimensionally shaped insulator according to any one of claims 1 to 4, comprising the steps of: A method for manufacturing a three-dimensional molded insulator, characterized in that a flat thermoplastic insulating sheet is subjected to secondary processing including thermoforming to form the recesses.

12. The method for manufacturing a three-dimensionally shaped insulator according to claim 11, wherein the thermoforming is vacuum forming or vacuum / pressure forming.

Images