Laminate structure

Abstract

To facilitate dispersion of heat of a laminate structure provided with a conductor to a surface side.SOLUTION: A transparent heater 1 includes: a layered first insulator 5 having grooves 7; a layered second insulator 6 located above the first insulator 5; and a conductor 3 disposed in the groove 7 and in contact with the second insulator 6. A thermal conductivity of the second insulator 6 is greater than that of the first insulator 5.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to laminate structures. [Background technology]

[0002] Patent Document 1 discloses a touch sensor (layer structure) including multiple substrates and multiple sensor electrodes provided on each substrate. Each of the multiple sensor electrodes is configured with a mesh pattern in which multiple conductive thin wires cross each other. One surface of each substrate is provided with a bottomed groove portion for forming the thin wires. A conductive layer made of a conductive metal such as copper is embedded in the groove portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-179898 Summary of the Invention [Problem to be solved by the invention]

[0004] In an electrical device including a laminated structure provided with conductive parts such as thin wires (hereinafter referred to as "conductors"), if heat generated by the passage of current through the conductors accumulates, it may have an undesirable effect on the performance of the electrical device. For this reason, there is a demand for diffusing heat on the surface of the laminated structure so that the heat does not build up inside the laminated structure.

[0005] Furthermore, when the laminated structure is a transparent heater, there is a demand for diffusing heat to the surface side in order to efficiently increase the surface temperature.

[0006] The present disclosure has been made in view of the above points, and its purpose is to make it easier to dissipate heat from a laminated structure provided with a conductor to the surface side. [Means for solving the problem]

[0007] One embodiment of the present disclosure relates to a laminated structure comprising a layered first insulator having a groove, a layered second insulator positioned above the first insulator, and a conductor disposed in the groove and in contact with the second insulator, wherein the thermal conductivity of the second insulator is greater than the thermal conductivity of the first insulator. [Effects of the Invention]

[0008] According to the present disclosure, heat from a laminated structure provided with a conductor can be easily diffused to the surface side. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a front view that schematically shows a transparent heater (laminate structure) according to the first embodiment provided over the entire surface of an automobile windshield, and a top view that shows a partially enlarged view of the configuration of the transparent heater. [Figure 2] FIG. 2 is an enlarged cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 3 is a schematic cross-sectional view showing a method for manufacturing a transparent heater. [Figure 4] FIG. 10 is a view corresponding to FIG. 2 according to a first modified example of the first embodiment. [Figure 5] FIG. 5 is a schematic cross-sectional view showing a fourth step and a fifth step in the method for manufacturing a transparent heater according to a first modified example of the first embodiment. [Figure 6] FIG. 6 is a view corresponding to FIG. 2 of a conductive member that is a laminated structure according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the present invention, its applications, or its uses.

[0011] (First embodiment) -Transparent heater- 1 and 2 show a laminated structure 1 according to a first embodiment. The laminated structure 1 according to this embodiment can be used as heat-generating glass by being attached to a glass plate via an adhesive such as OCA. Hereinafter, the laminated structure 1 according to this embodiment will be referred to as a transparent heater 1. Note that FIG. 1 schematically shows an automobile 100 in which a transparent heater 1 is provided over the entire surface of a windshield FG. Also, within the dashed rectangular frame in FIG. 1, an enlarged portion of the transparent heater 1 provided over the entire surface of the windshield FG of the automobile 100 is shown.

[0012] As shown in FIG. 1, the transparent heater 1 comprises a transparent substrate 2, a conductor 3 formed in the shape of a thin wire and provided on the substrate 2, and a power source (not shown) for passing a current through the conductor 3. The transparent heater 1 is configured to generate heat when a current flows through the conductor 3, and the heat is diffused over the entire surface of the substrate 2. Note that the front side of the transparent heater 1 is the front side of the paper in FIG. 1 and corresponds to the upper side of FIGS. 2 to 6, and the back side of the transparent heater 1 corresponds to the opposite side. In the following description, the front side may be referred to as the upper surface, and the back side may be referred to as the lower surface.

[0013] The configuration of the substrate 2 and the conductor structure 4 including the conductor 3 and its surrounding configuration will be described in detail below.

[0014] -substrate- 2, the transparent heater 1 includes a layered first insulator 5 and a layered second insulator 6 located above the first insulator 5, and the first insulator 5 and the second insulator 6 are stacked to form a substrate 2. The substrate 2 has an outer shape, for example, rectangular, when viewed from above.

[0015] There are no particular limitations on the materials for the first insulator 5 and the second insulator 6. For example, the first insulator 5 and the second insulator 6 may both be transparent resin materials having at least one of the properties of heat curing, ultraviolet curing, and thermoplasticity. Specifically, the first insulator 5 and the second insulator 6 are preferably made of an acrylic resin material, an epoxy resin material, a urethane resin material, a polyester resin material, or a resin material that is a selective combination of any of these resin materials.

[0016] The first insulator 5 and the second insulator 6 may be made of the same type of resin material. However, considering the manufacturing method shown in Fig. 3 and described below, a relatively brittle (easily broken) resin material is suitable for the material of the second insulator 6. Specifically, even if the first insulator 5 and the second insulator 6 are made of the same type of resin material, it is desirable that the second insulator 6 be made of, for example, a low molecular weight chain.

[0017] The resin material of the second insulator 6 is preferably made to have a lower molecular chain than the resin material of the first insulator 5 by controlling the degree of polymerization. In this way, in the fourth step S4 of the manufacturing method described below, if the adhesion between the second insulator 6 and the film substrate 11 (described later) exceeds the fracture strength of the second insulator 6, the second insulator 6 will fracture near the opening end of each groove 7 (see FIG. 3).

[0018] The resin material of the second insulator 6 may contain an inorganic filler to facilitate breaking of the second insulator 6 in a fourth step S4 of the manufacturing method, which will be described later. When the resin material of the second insulator 6 contains an inorganic filler, the bonds between molecules are broken, making the second insulator 6 more likely to break.

[0019] The thicknesses of the first insulator 5 and the second insulator 6 are not limited, but in this embodiment, the thickness of the second insulator 6 is the same as the thickness of the first insulator 5. The thicknesses of the first insulator 5 and the second insulator 6 are, for example, not less than 3 μm and not more than 20 μm.

[0020] The thermal conductivity of the second insulator 6 is greater than that of the first insulator 5. Specifically, the thermal conductivity of the second insulator 6 is 10 to 20 times greater than that of the first insulator 5. In this embodiment, in order to make the thermal conductivity of the second insulator 6 greater than that of the first insulator 5, a filler with high thermal conductivity is added to the second insulator 6. Such a filler may be either an inorganic filler or an organic filler, but inorganic fillers are preferred. Examples of inorganic fillers include metal oxides, hydroxides, carbonates, nitrides, carbides, etc., and oxides, hydroxides, or carbonates are preferred. Examples of oxides include silicon oxide, aluminum oxide, magnesium oxide, etc.; examples of hydroxides include aluminum hydroxide, magnesium hydroxide, calcium hydroxide, etc.; and examples of carbonates include magnesium carbonate, calcium carbonate, etc. The particle size of the filler is preferably 0.1 μm or more and 1 μm or less, and the content of the filler in the second insulator 6 is preferably 20% by weight or more and 60% by weight or less. Note that the thermal conductivity of the second insulator 6 without the filler added is, for example, 0.14 W / m·K or more and 0.21 W / m·K or less, but by adding the filler, the thermal conductivity of the second insulator 6 can be increased to, for example, 1 W / m·K or more and 3 W / m·K or less.

[0021] The first insulator 5 has a groove 7 in which the conductor 3 is disposed. The groove 7 is formed by being recessed downward from the surface 5a of the first insulator 5. The dimensions of the groove 7 are not particularly limited, but for example, the depth (D) of the groove 7 is 1.5 μm or more and 3.0 μm or less, and the width (W1) of the groove 7 is 0.5 μm or more and 15 μm or less.

[0022] The second insulator 6 has a through portion 8 that penetrates in the vertical direction at a portion that overlaps with the groove portion 7 in a top view. In other words, the through portion 8 extends along the groove portion 7 in a top view and communicates with the groove portion 7 as shown in Fig. 2. The width (W2) of the through portion 8 is preferably equal to or greater than the width (W1) of the groove portion 7 of the first insulator 5. The width (W2) of the through portion 8 is preferably equal to or greater than 0.5 µm and equal to or less than 20 µm.

[0023] 2, small irregularities are formed on the side portions 8a of the through portion 8 of the second insulator 6. For this reason, the surface roughness (Ra) of the side portions 8a (portions that come into contact with the conductor) of the through portion 8 of the second insulator 6 is greater than the surface roughness of the upper surface (surface 2a of the substrate 2) of the second insulator 6. The surface roughness (Ra) of the side portions 8a of the through portion 8 is preferably 0.1 μm or more and 0.5 μm or less.

[0024] Here, surface roughness (Ra) refers to the arithmetic mean roughness. The arithmetic mean roughness is the value, expressed in micrometers (μm), obtained by extracting a reference length from a roughness curve in the direction of the mean line, plotting the X axis in the direction of the mean line of the extracted portion and the Y axis in the direction of the longitudinal magnification, and expressing the roughness curve as y = f(χ) using a specific formula (see JIS B 0601:1994, JIS B 0031:1994). Surface roughness (Ra) is calculated from the surface height measured by atomic force microscopy (AFM).

[0025] -Conductor structure- As shown in Fig. 2, the conductor structure 4 includes a resin layer 9 disposed in the groove 7 of the first insulator 5, and a conductor 3 disposed on the resin layer 9 in the groove 7. In Fig. 2, the conductor 3 and the resin layer 9 are each highlighted with dot hatching.

[0026] The resin layer 9 is a base layer for forming the conductor 3 in the groove portion 7. The resin layer 9 is made of a resin solvent containing an electroless plating catalyst. The electroless plating catalyst includes, for example, palladium (Pd). The electroless plating catalyst may include platinum (Pt) or chromium (Cr) instead of palladium (Pd).

[0027] The resin layer 9 is disposed on the bottom 7a and side portions 7b, 7b of the groove 7 and on the surface 5a of the first insulator 5 located around the groove 7. The resin layer 9 corresponds to a solid component containing palladium (Pd) remaining in the groove 7 and on the surface 5a after the solvent component has evaporated due to drying. The thickness (T) of the resin layer 9 is, for example, not less than 10 nm and not more than 100 nm.

[0028] The conductor 3 is, for example, a plating layer formed by electroless plating. Specifically, the conductor 3 is laminated on the resin layer 9 disposed in the groove 7 by electroless plating.

[0029] The conductor 3 is composed of a conductive material. Examples of this conductive material include conductive metals such as copper (Cu), gold (Au), silver (Ag), aluminum (Al), nickel (Ni), or alloys thereof.

[0030] The conductor 3 has a first conductor 3a located inside the groove 7 and a second conductor 3b located above the first conductor 3a. The second conductor 3b is formed integrally with the first conductor 3a from the same material as the first conductor 3a. In the present embodiment, as shown in FIG. 2, the cross-sectional shape of the first conductor 3a is a trapezoid corresponding to the cross-sectional shape of the groove 7, and the cross-sectional shape of the second conductor 3b is a substantially rectangular shape.

[0031] The boundary (A) between the first conductor 3a and the second conductor 3b is defined as a position substantially flush with the surface 5a of the first insulator 5. Thereby, the height (H1) of the first conductor 3a is a value obtained by subtracting the thickness (T) of the resin layer 9 from the depth (D) of the groove 7. Also, the height (H2) of the second conductor 3b corresponds to the distance from the interface A to the upper surface (upper end portion) of the second conductor 3b. The height (H1) of the first conductor 3a and the height (H2) of the second conductor 3b are each preferably 0.5 μm or more and 5 μm or less, and preferably satisfy the relationship H1 < H2, and more preferably satisfy the relationship 0.3 < H2 / H1 < 2 from the viewpoint of ease of manufacture. The height (H3) of the conductor 3 is preferably 1.5 μm or more and 6.0 μm or less.

[0032] The conductor 3 contacts the side portion 8a of the through-hole 8 of the second insulator 6. The second conductor 3b is exposed upward in the through-hole 8.

[0033] - Manufacturing method - 3 shows a method for manufacturing the transparent heater 1. This manufacturing method includes a first step S1 to a fifth step S5.

[0034] In the first step S1, a plurality of grooves 7 are formed in the first insulator 5 by, for example, an imprinting method.

[0035] In the second step S2, a resin layer 9 is formed on the surface 5a and grooves 7 of the first insulator 5. Specifically, in the first insulator 5 having the grooves 7 formed therein, a plating primer is coated onto the surface 5a and grooves 7 of the first insulator 5 using a bar coater or printing. The plating primer is made of a resin solvent containing, for example, an electroless plating catalyst (Pd).

[0036] In the coating process, the liquid plating primer is dried for a predetermined time, causing the solvent components in the plating primer to volatilize. As this volatilization progresses, the solid components containing palladium (Pd) solidify. As a result, a resin layer 9 is formed on the surface 5a of the first insulator 5 and in the grooves 7.

[0037] In the third step S3, first, a film substrate 11 is prepared, the back surface of which is laminated with a coating layer 10 that will become the second insulator 6. The coating layer 10 is a thermal transfer layer that is made of, for example, a UV-curable resin and is thermocompression-bonded as described below. Note that the coating layer 10 does not have to be a UV-curable resin. Next, the coating layer 10 is placed so that it contacts the resin layer 9 on the first insulator 5. At this time, the film substrate 11 and the coating layer 10 are flat and do not fit along the grooves 7, as shown in FIG. 3 , so the coating layer 10 does not contact the resin layer 9 provided inside the grooves 7. Next, a heating roller (R) is pressed against the film substrate 11, thereby thermocompression-bonding the coating layer 10 to the resin layer 9 on the first insulator 5.

[0038] In the fourth step S4, the film substrate 11 is peeled off from the first insulator 5. At this time, because the coating layer 10 and the film substrate 11 are adhered to each other and the coating layer 10 and the resin layer 9 are adhered to each other, the coating layer 10 remains adhered to the resin layer 9 except for the groove portion 7, and the coating layer 10 located above the groove portion 7 is broken from the coating layer 10 on the resin layer 9 while remaining adhered to the film substrate 11. As a result, an opening that becomes the through portion 8 is formed above the groove portion 7. The breakage of the coating layer 10 causes small irregularities on the side portion 8a of the through portion 8.

[0039] In the fifth step S5, the coating layer 10 is cured by irradiating it with UV light. If it is not necessary to cure the coating layer 10 in the laminated structure 1, the fifth step S5 may be omitted.

[0040] -Action and effect- In this embodiment, the thermal conductivity of the second insulator 6 on the front side is greater than the thermal conductivity of the first insulator 5 on the back side, making it easier to diffuse heat from the transparent heater 1 to the front side. Also, in the transparent heater 1, the second insulator 6 has a high thermal conductivity, making it easier for heat to diffuse inside the second insulator 6. As a result, uneven heat distribution on the surface of the transparent heater 1 can be suppressed.

[0041] In this embodiment, the thermal conductivity of the second insulator 6 is at least ten times that of the first insulator 5, so that the heat of the transparent heater 1 is easily diffused particularly toward the surface side.

[0042] In this embodiment, the thermal conductivity of the second insulator 6 is 20 times or less than the thermal conductivity of the first insulator 5, thereby reducing the difference in linear expansion coefficient (thermal expansion coefficient) between the first insulator 5 and the second insulator 6, making it easier to maintain adhesion between the first insulator 5 and the second insulator 6.

[0043] In this embodiment, the second insulator 6 contains a filler, which makes it easier to increase the thermal conductivity of the second insulator 6. Furthermore, increasing the thermal conductivity of the second insulator 6 makes it easier to diffuse the heat of the transparent heater 1 toward the surface side.

[0044] (First Modification of the First Embodiment) 4 shows a transparent heater 1 according to a first modified example of the first embodiment. In this modified example, the side portions 8a of the through portions 8 in the second insulator 6 are inclined relative to the vertical direction so that the width of the through portions 8 along the upper surface of the second insulator 6 is longer than the width of the through portions 8 along the lower surface of the second insulator 6. When the inclination angle of the side portions 8a of the through portions 8 relative to the vertical direction in a cross section cut along a direction perpendicular to the extension direction of the through portions 8 is θ, θ is preferably 5° or more and 30° or less.

[0045] 4, the side portion 8a of the through portion 8 is formed in a straight line as long as the width along the upper surface of the second insulator 6 is longer than the width of the through portion 8 along the lower surface of the second insulator 6. For example, the side portion 8a of the through portion 8 may be formed in a curved line as viewed in cross section, or the side portion 8a may have irregularities.

[0046] The manufacturing method of the transparent heater 1 according to this modified example is the same as the manufacturing method of the embodiment shown in FIG. 3, except that the preferred material for the coating layer 10 (thermal transfer layer) used in the first step S1 is a thermosetting resin, and that in the fifth step S5, the coating layer 10 is thermally cured as shown in FIG. 5.

[0047] In the fifth step S5 of this modification, the second insulator 6 is thermally cured, thereby deforming so that the width of the through portion 8 increases on the opening side (upper side). Specifically, the application of heat to the side portion 8a of the through portion 8 promotes the curing shrinkage of the second insulator 6. As a result, as shown in FIGS. 4 and 5, the side portion 8a of the through portion 8 becomes an inclined surface that is inclined in the vertical direction.

[0048] As in this modification, when the width of the through portion 8 in the second insulator 6 along the upper surface of the second insulator 6 is longer than the width of the through portion 8 along the lower surface of the second insulator 6, the second conductor 3b can come into contact over a wide area with the side portion 8a of the through portion 8. As a result, the heat generated by energizing the conductor 3 is diffused into the second insulator 6, and the heat of the transparent heater 1 is more likely to diffuse toward the surface side.

[0049] (Second Modification of the First Embodiment) In the first embodiment, the first insulator 5 and the second insulator 6 have the same thickness, but the second insulator 6 may be thicker than the first insulator 5. With this configuration, the vertical dimension of the side portion 8a of the through portion 8 is larger than in the first embodiment, so that the second conductor 3b can come into contact with the side portion 8a of the through portion 8 over a wider area. As a result, heat generated by energizing the conductor 3 is diffused into the second insulator 6, and the heat of the transparent heater 1 is more likely to diffuse toward the surface side.

[0050] (Second embodiment) The configuration of the second embodiment of the present disclosure will be described below. Note that, in the following, descriptions of configurations common to the first embodiment may be omitted, and the same reference numerals as in the first embodiment will be used for the configurations common to the first embodiment.

[0051] The laminated structure 12 according to this embodiment can be applied to electronic devices (e.g., surveillance cameras) in which electronic components such as LED elements and diodes are mounted. The laminated structure 12 according to this embodiment can also be applied, for example, as an anti-fogging transparent heater attached to the lens surface of ski goggles or eyeglasses. Hereinafter, the laminated structure 12 according to this embodiment will be referred to as a conductive member 12.

[0052] In the conductive member 12, the first insulator 5 is made of a thermosetting resin or an ultraviolet curing resin having insulating properties and optical transparency. The second insulator 6 is also made of a resin having insulating properties and optical transparency. The thickness of the first insulator 5 is preferably 1.8 μm or more and 5.2 μm or less, and the thickness of the second insulator 6 is preferably 0.5 μm or more and 3.2 μm or less.

[0053] In the conductive member 12, the conductive structure 4 is different from that in the first embodiment, as shown in FIG.

[0054] The through portion 8 of the second insulator 6 is formed in the shape of a groove whose width gradually decreases downward from the surface 6a of the second insulator 6. The through portion 8 penetrates in the vertical direction at its bottom portion 8b. The groove width of the through portion 8 along the surface 6a of the second insulator 6 is configured to be larger than the groove width of the groove portion 7 of the first insulator 5. Specifically, the groove width of the through portion 8 along the surface 6a of the second insulator 6 is set to be, for example, not less than 1.1 μm and not more than 34.0 μm.

[0055] The first conductor 3a is located inside the groove 7 of the first insulator 5, and includes a first adhesion layer 13 arranged in the groove 7, a first conductive layer 14 arranged on the first adhesion layer 13, and a first blackening layer 15 arranged on the first conductive layer 14, as shown in FIG. 6. At least a portion of the upper surface of the first conductor 3a is in contact with the lower surface of the second insulator 6, as shown in FIG.

[0056] The first adhesive layer 13 is an element for ensuring the adhesion of the first conductive layer 14 to the groove portion 7. The first adhesive layer 13 has low reflectivity. That is, the first adhesive layer 13 has the function of making the first conductive layer 14 less visible when the conductive member 12 is viewed from below.

[0057] The first adhesion layer 13 is a metal layer made of, for example, a metal nitride containing at least one metal selected from the group consisting of Ti, Al, V, W, Ta, Si, Cr, Ag, Mo, Cu, and Zn, a metal oxide, or a metal oxynitride containing both a metal nitride and a metal oxide. The first adhesion layer 13 may be a single layer or a laminate of multiple layers with different compositions.

[0058] The first adhesive layer 13 is laminated in the form of a thin film on the bottom 7a and side 7b of the groove 7 by vapor deposition, sputtering, or the like.

[0059] The first conductive layer 14 is an element for ensuring the conductivity of the conductor structure 4 in the groove portion 7 of the first insulator 5. The first conductive layer 14 is laminated on the first adhesive layer 13. The upper surface of the first conductive layer 14 is recessed downward from a position corresponding to the surface 5a of the first insulator 5 in a cross-sectional view. Note that instead of the configuration in which the upper surface of the first conductive layer 14 is recessed downward (the configuration shown in FIG. 6 ), the upper surface of the first conductive layer 14 may be configured to be horizontally straight in the plane of FIG. 6 . More specifically, the upper surface of the first conductive layer 14 may be flush with the surface 5a of the first insulator 5. Alternatively, the upper surface of the first conductive layer 14 may be horizontally straight in the plane of FIG. 6 and slightly higher than the surface 5a of the first insulator 5.

[0060] Suitable conductive materials for the first conductive layer 14 include, for example, copper, silver, gold, or an alloy containing at least one of these metals. The first conductive layer 14 is formed by, for example, vapor deposition, sputtering, electroless plating, or electroplating.

[0061] The first blackening layer 15 has the function of making the first conductive layer 14 less visible when the conductive member 12 is viewed from above. The first blackening layer 15 is laminated on the opening side of the groove portion 7 in the first insulator 5.

[0062] The first blackened layer 15 is formed by substituting, with palladium (blackening treatment), copper crystal grains located at the boundaries between copper crystal grains located on the surface of the first conductive layer 14. The thickness of the first blackened layer 15 is, for example, not less than 10 nm and not more than 500 nm.

[0063] The second conductor 3b is located above the first conductor 3a and is in contact with the second insulator 6. As shown in FIG. 6 , the second conductor 3b includes a second adhesive layer 16 disposed at the through portion 8 of the second insulator 6, a second conductive layer 17 disposed on the second adhesive layer 16, and a second blackening layer 18 disposed on the second conductive layer 17.

[0064] The second adhesive layer 16 is an element for ensuring the adhesion of the second conductive layer 17 to the through portion 8. The second adhesive layer 16 has low reflectivity. That is, the second adhesive layer 16 has the function of making the second conductive layer 17 less visible when the conductive member 12 is viewed from below.

[0065] The second adhesion layer 16 is a metal layer composed of, for example, a metal nitride containing at least one metal selected from the group consisting of Ti, Al, V, W, Ta, Si, Cr, Ag, Mo, Cu, and Zn, a metal oxide, or a metal oxynitride containing both a metal nitride and a metal oxide. The second adhesion layer 16 may be a single layer or a laminate of multiple layers with different compositions.

[0066] The second adhesive layer 16 is laminated in the form of a thin film on the side portion 8a and the bottom portion 8b of the through portion 8 by vapor deposition, sputtering, or the like.

[0067] The second conductive layer 17 is an element for ensuring the conductivity of the conductor structure 4 at the through portion 8 of the second insulator 6. The second conductive layer 17 is directly connected to the electronic component. The second conductive layer 17 is laminated on the second adhesive layer 16. In a cross-sectional view, the upper surface of the second conductive layer 17 is recessed downward from a position corresponding to the surface 6a of the second insulator 6. Note that, instead of the configuration shown in FIG. 6 , the upper surface of the second conductive layer 17 may be formed to be flush with the surface 6a of the second insulator 6.

[0068] Suitable conductive materials for forming second conductive layer 17 include, for example, copper, silver, gold, and alloys containing at least one of these metals. Second conductive layer 17 is formed by, for example, vapor deposition, sputtering, electroless plating, or electroplating.

[0069] The second blackened layer 18 has the function of making the second conductive layer 17 less visible when the conductive member 12 is viewed from above.

[0070] The second blackened layer 18 is formed by substituting, with palladium (blackening treatment), copper crystal grains located at the boundaries between copper crystal grains located on the surface of the second conductive layer 17. The thickness of the second blackened layer 18 is, for example, not less than 10 nm and not more than 500 nm.

[0071] The through-hole 8 of the second insulator 6 penetrates in the vertical direction at the bottom 8b, thereby forming a connection portion (Cp) where the first conductive layer 14 and the first blackening layer 15 are electrically connected to the second adhesive layer 16 and the second conductive layer 17. This connection portion (Cp) is configured to be continuous along the extension direction of both the first conductor 3a and the second conductor 3b.

[0072] In this embodiment, at least a portion of the upper surface of the first conductor 3a is in contact with the lower surface of the second insulator 6, so that the heat generated by passing electricity through the first conductor 3a is diffused to the second insulator 6, and the heat of the conductive member 12 is easily diffused to the surface side.

[0073] In this embodiment as well, the thermal conductivity of the second insulator 6 is greater than the thermal conductivity of the first insulator 5. This facilitates heat diffusion within the second insulator 6. In other words, heat is diffused over the entire surface of the conductive member 12. As a result, heat can be efficiently dissipated.

[0074] For example, if the back side of the conductive member 12 is placed on an electronic device (not shown), heat generated by energizing the first conductor 3a is prevented from being transmitted to electronic components (e.g., LED elements, diodes) mounted on the electronic device. As a result, the electronic components mounted on the electronic device can be appropriately protected from the effects of heat. Specifically, for example, if the back side of the conductive member 12 is attached to the surface of the lens of a surveillance camera (not shown), which is an example of the electronic device, for the purpose of preventing fogging, heat generated by energizing the first conductor 3a escapes toward the side opposite the surveillance camera lens. In other words, heat generated by energizing the first conductor 3a is not transmitted to elements such as a CCD mounted inside the surveillance camera. As a result, elements such as a CCD mounted inside the surveillance camera can be appropriately protected from the effects of heat.

[0075] Furthermore, for example, when the front surface side of the conductive member 12 is placed on an electronic device, heat generated in electronic components (LED elements, diodes, etc.) mounted on the electronic device is not trapped in the second insulator 6 but is diffused from the front surface side of the conductive member 12. As a result, the electronic components mounted on the electronic device can be appropriately protected from the effects of heat.

[0076] Furthermore, for example, if the back side of the conductive member 12 is attached to the lens surface side (opposite the side where the human eyeballs are located) of ski goggles or eyeglasses, heat will not be trapped near the human eyeballs, and as a result, the eyes of the person wearing the ski goggles or eyeglasses can be kept safe.

[0077] (Other embodiments) In the first embodiment, the surface roughness of the side portion 8a at the through portion 8 of the second insulator 6 is greater than the surface roughness of the upper surface of the second insulator 6 (surface 2a of the substrate 2), but the present disclosure is not necessarily limited to this configuration, and it is sufficient that the surface roughness of the portion of the second insulator 6 that comes into contact with the conductor 3 is greater than the surface roughness of the upper surface of the second insulator 6.

[0078] The second insulator 6 does not necessarily have to be provided with the through-hole 8. In this case, the conductor 3 comes into contact with the lower surface of the second insulator 6. In this case, it is preferable that the surface roughness of the lower surface of the second insulator 6 is greater than the surface roughness of the upper surface of the second insulator 6. The greater surface roughness of the lower surface of the second insulator 6 improves adhesion between the first insulator 5 and the second insulator 6.

[0079] In the present disclosure, the thermal conductivity of the second insulator 6 needs to be greater than that of the first insulator 5, and the thermal conductivity of the second insulator 6 may be less than 10 times or more than 20 times that of the first insulator 5. The second insulator 6 does not need to contain a filler. In that case, the materials of the first insulator 5 and the second insulator 6 should be selected so that the thermal conductivity of the second insulator 6 is greater than that of the first insulator 5.

[0080] In the above-described embodiments and modifications, the transparent heater 1 and the conductive member 12 are described as examples of the laminated structure according to the present disclosure, but the laminated structure according to the present disclosure is not limited to these. For example, the laminated structure according to the present disclosure can be widely applied to touch sensors, liquid crystal display devices, organic electroluminescence display devices (OLEDs), micro LED display devices, solar cell devices, touch sensors, antenna devices, electromagnetic wave shielding sheets, etc. [Industrial Applicability]

[0081] The present disclosure is industrially applicable as a laminated structure used in transparent heaters, conductive members, etc. [Explanation of symbols]

[0082] 1 Transparent heater (laminated structure) 2 boards 2a: Surface of the substrate (surface of the second insulating layer) 3 Conductors 3a First conductor 3b Second conductor 4 Conductor structure 5 First insulator 5a Surface of first insulator 6 Second insulator 6a Surface of second insulator 7 Groove 7a Bottom of groove 7b Side of groove 8 Penetration 8a Side of penetration 8b Bottom of penetration 9 Resin layer 10 Coating Layer 11 Film substrate 12 Conductive material (laminated structure) 13 First adhesive layer 14 First conductive layer 15 First blackened layer 16 Second adhesive layer 17 Second conductive layer 18 Second blackened layer W1 Groove width W2 Width of the penetration H1 Height of the first conductor H2 Height of the second conductor H3 Conductor height S1 1st process S2 2nd process S3 3rd process S4 4th process S5 5th process R Heating Roller

Claims

1. a layered first insulator having a groove; a layer-like second insulator located above the first insulator; a conductor disposed in the groove and in contact with the second insulator; Equipped with The thermal conductivity of the second insulator is greater than the thermal conductivity of the first insulator. Laminated structure.

2. The laminated structure according to claim 1 , wherein the thermal conductivity of the second insulator is 10 to 20 times greater than the thermal conductivity of the first insulator.

3. The laminated structure according to claim 1 , wherein the second insulator includes a filler.

4. The conductor is a first conductor located inside the groove; a second conductor located above the first conductor and integral with the first conductor; and The laminated structure according to any one of claims 1 to 43, wherein the second conductor is in contact with the second insulator.

5. The conductor is a first conductor located inside the groove; a second conductor located above the first conductor and in contact with the second insulator; and The laminated structure according to any one of claims 1 to 3, wherein at least a portion of an upper surface of the first conductor is in contact with a lower surface of the second insulator.

6. the second insulator has a through portion extending along the groove and communicating with the groove; The laminated structure according to claim 4 , wherein the second conductor is exposed upward at the through portion.

7. The laminated structure according to claim 6 , wherein the thickness of the second insulator is greater than the thickness of the first insulator.

8. The laminated structure according to claim 6 , wherein a surface roughness of the portion of the second insulator that contacts the conductor is greater than a surface roughness of an upper surface of the second insulator.

9. The laminated structure according to claim 6 , wherein a width of the through portion along the upper surface of the second insulator is greater than a width of the through portion along the lower surface of the second insulator.

10. The laminated structure according to any one of claims 1 to 9, which is a transparent heater.

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