JP2023065884A - Current-carrying member and heater - Google Patents

Abstract

To provide a current-carrying member and a heater which can suppress local deterioration caused by heat generation while allowing electromagnetic waves in a specific frequency bandwidth to be transmitted therethrough.SOLUTION: A current-carrying member has a conductive film 13. The conductive film 13 has: a conductive part made up of multiple pieces of wiring; and a plurality of non-conductive parts 22. The non-conductive parts 22 include a plurality of units U1 extending from points C1 in different directions. Two of the non-conductive parts 22 adjacent to each other are arranged in such a manner that their coupling points C1 may be adjacent to each other in a direction where the units U1 extend. The closest units U1 of the two non-conductive parts 22 extend in a direction where they face each other. The conductive part has a narrowing conductive region R1 which is located between the closest units U1. The wiring density in the narrowing conductive region R1 is higher than that in other regions.SELECTED DRAWING: Figure 4

Description

TECHNICAL FIELD The present invention relates to a current-carrying member having transparency to electromagnetic waves in a specific frequency band and a heater provided with the current-carrying member.

2. Description of the Related Art Conventionally, sensors, communication devices, and the like using electromagnetic waves such as so-called millimeter waves and microwaves have been generally used. These devices are mounted in automobiles, for example, and are often covered with protective covers. It is known that the accumulation of snow and ice on the cover, or the fogging caused by water vapor or the like causes erroneous detection in sensors arranged inside the cover or communication failure in communication equipment. In order to remove snow, ice, and fog, a heat-generating member as disclosed in Patent Document 1, for example, has been developed. The heat-generating member of Patent Document 1 includes a three-dimensional structure with a layer to be plated and a conductive laminate having a metal layer disposed on the layer to be plated, and the metal layer functions as a heating wire.

In addition, for example, the conductive surface formed by the heat-generating member or the like of Patent Document 1 absorbs or reflects electromagnetic waves transmitted and received by the sensor and communication equipment, etc., so that the sensitivity of the sensor and communication equipment decreases and false detection occurs. known to cause. For example, a metal mesh structure as disclosed in Non-Patent Document 1 is known in order to suppress such sensor sensitivity reduction and erroneous detection. The metal mesh of Non-Patent Document 1 is formed with a plurality of cross-shaped non-conductive portions arranged in a grid pattern along two directions perpendicular to each other. These non-conductive portions facilitate transmission of electromagnetic waves in the frequency band corresponding to the cross-shaped size through the metal mesh.

WO2017/163830

Vyachesla V. Komarov, Valery P.; Meschanov, “Transmission properties of metal mesh filters at 90 GHz,” Journal of Computational Electronics, Feb. 28, 2019, 18:696-704.

However, the heat-generating member disclosed in Patent Document 1 cannot transmit only electromagnetic waves in a specific frequency band. It was difficult.
In addition, the present inventors found that when the metal mesh disclosed in Non-Patent Document 1 is energized to generate heat, the current flows intensively between a plurality of non-conductive parts. It was discovered that the metal mesh deteriorates, for example, the metal mesh is oxidized at that portion due to localized heat generation. Therefore, it is conceivable to widen the interval between the plurality of non-conductive portions in order to avoid concentration of the current. I had a problem with it going down.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a current-carrying member capable of suppressing local deterioration due to heat generation while transmitting electromagnetic waves in a specific frequency band.

In order to achieve the above object, a current-carrying member according to the present invention is a current-carrying member having a conductive film formed thereon, wherein the conductive film forms a conductive portion composed of a plurality of wirings and a regular repeating pattern. each of the plurality of non-conductive portions is connected to each other at a connection point and has a plurality of unitary units having an elongated shape extending in mutually different directions from the connection point. two non-conductive parts adjacent to each other are arranged so that the connection points are adjacent to each other in the direction in which the unit units extend, and the unit units closest to each other of the two non-conductive parts are arranged in the direction facing each other The conductive portion has a constricted conductive region located between the unit units closest to each other of the two non-conductive portions, and the wiring density of the wiring in the constricted conductive region is the same as that in the region of the conductive portion other than the constricted conductive region. The wiring density is higher than that of the wiring.

The plurality of wirings form a mesh shape in which the plurality of unit cells are arranged, the wiring in the constricted conductive region has at least one auxiliary wiring arranged inside the unit cells included in the constricted conductive region, Preferably, the auxiliary wiring divides the unit cell by being connected to wiring forming the outline of the unit cell at both ends.
Also, the auxiliary wiring can extend along the direction of the current flowing through the constricted conductive region.

The distance between the closest unit units of the two non-conductive parts is preferably less than twice the length of the unit unit.
Further, it is more preferable that the distance between the two non-conductive portions closest to each other is 0.3 times or more the length of the unit unit and 0.6 times or less the length of the unit unit.

The non-conducting part is composed of four unit units, and the four unit units can be connected to each other at connection points to form a cross shape.
The conductive film can have a shape along a curved surface.

A heater according to the present invention includes the conducting member described above.

According to the current-carrying member of the present invention, a conductive film is formed, and the conductive film has a conductive portion composed of a plurality of wirings and a plurality of non-conductive portions arranged so as to form a regular repeating pattern. and each of the plurality of non-conductive portions includes a plurality of elongated unit units connected to each other at the connection point and extending in different directions from the connection point, and the connection points are adjacent to each other in the direction in which the unit units extend. two non-conductive portions adjacent to each other are arranged so that the unit units closest to each other of the two non-conductive portions extend in directions facing each other; It has a constricted conductive area located between the closest unit units, and the wiring density of the wiring in the constricted conductive area is higher than the wiring density of the wiring in the area of the conductive part other than the constricted conductive area. local deterioration due to heat generation can be suppressed while allowing electromagnetic waves to pass through.

FIG. 2 is a cross-sectional view schematically showing part of the current-carrying member according to Embodiment 1 of the present invention; FIG. 2 is a partial plan view of a conductive film according to Embodiment 1 of the present invention; 4 is an enlarged view of a conductive portion according to Embodiment 1 of the present invention; FIG. It is a figure which expands and shows the non-conductive part in Embodiment 1 of this invention. FIG. 10 is a diagram showing an example of a conductive film without auxiliary wiring; FIG. 10 is a partial plan view of a conductive film in a first modification of Embodiment 1 of the present invention; FIG. 11 is a partial plan view of a conductive film in a second modification of Embodiment 1 of the present invention; FIG. 11 is a partial plan view of a conductive film in a third modification of Embodiment 1 of the present invention; FIG. 11 is a partial plan view of a conductive film in a fourth modification of the first embodiment of the invention; FIG. 11 is a partial plan view of a conductive film in a fifth modification of the first embodiment of the invention; FIG. 10 is a partial plan view of a conductive film according to Embodiment 2 of the present invention; FIG. 10 is an enlarged view of four non-conductive portions adjacent to each other in the direction in which a plurality of unit units extend according to the second embodiment of the present invention; 4 is a schematic enlarged view of a constricted conductive region in Example 1. FIG. FIG. 10 is a diagram showing another example of a conductive film having no auxiliary wiring; FIG. 10 is a diagram showing still another example of a conductive film having no auxiliary wiring;

The current-carrying member of the present invention will be described in detail below based on preferred embodiments shown in the accompanying drawings.
It should be noted that the drawings described below are examples for explaining the present invention, and the present invention is not limited to the drawings shown below.
In the following, "~" indicating a numerical range includes the numerical values described on both sides. For example, when ε is a numerical value α to a numerical value β, the range of ε is a range including the numerical values α and β, and represented by mathematical symbols α≦ε≦β.
Angles such as “parallel” and “perpendicular” include error ranges generally accepted in the relevant technical field unless otherwise specified.
In addition, "same" includes the margin of error that is generally allowed in the relevant technical field.

Moreover, "(meth)acrylate" represents both or either of acrylate and methacrylate, and "(meth)acryl" represents both or either of acrylic and methacrylic. Moreover, "(meth)acryloyl" represents both or either of acryloyl and methacryloyl.
Unless otherwise specified, the term “transparent to visible light” means that the visible light transmittance is 40% or more, preferably 80.0% or more, in the visible light wavelength range of 380 nm to 800 nm. More preferably, it is 90.0% or more. Moreover, in the following description, the term “transparent” means transparent to visible light unless otherwise specified.
The visible light transmittance is measured using "Plastics--Determination of Total Light Transmittance and Total Light Reflectance" defined in JIS (Japanese Industrial Standards) K 7375:2008.

Embodiment 1
FIG. 1 shows a conducting member 11 according to Embodiment 1 of the present invention. The current-carrying member 11 is a film-like member and includes an insulating transparent substrate 12 and a conductive film 13 formed on one side of the substrate 12 .
The conductive film 13 is transparent and has a visible light transmittance of, for example, 75.0% or more.

As shown in FIG. 2, the conductive film 13 includes a mesh-shaped conductive portion 21 composed of a plurality of wirings M1 and a plurality of cross-shaped non-conductive portions 22 arranged to form a regular repeating pattern. have.

A plurality of wirings M1 extend along a predetermined direction and a direction orthogonal to the direction. Hereinafter, the two orthogonal directions in which the wirings M1 extend are referred to as the X direction and the Y direction. In particular, in FIG. 2, the direction from bottom to top is called +Y direction, the direction from top to bottom is called -Y direction, the direction from left to right is called +X direction, and the direction from left to right is called -X direction.

A pair of non-conductive portions 22 adjacent in the X direction and a pair of non-conductive portions 22 adjacent in the Y direction are closest to each other along the X direction and the Y direction. arranged at intervals.

A cross-shaped edge portion G1 of the non-conductive portion 22 is formed by a plurality of wirings M1. The inner side of the edge G1 is a region where the wiring M1 does not exist and electricity does not pass.

Here, in FIG. 2, in order to make the explanation easier to understand, the edges G1 of the plurality of non-conductive portions 22 are drawn with thicker lines than the plurality of wirings M1 arranged at positions other than the edges G1. However, actually, the plurality of wirings M1 forming the edge G1 and the plurality of wirings M1 arranged at other positions have the same line width.

As shown in FIG. 3, the plurality of wirings M1 forming the conductive portion 21 have a wiring width W and are arranged at a mesh pitch E defined as the distance between the center lines CL of the wirings M1. The plurality of wirings M1 form a mesh shape in which a plurality of rectangular unit cells A1 are arranged.

The line width T of the wiring M1 is not particularly limited, but the upper limit is preferably 1000.00 μm or less, more preferably 500.00 μm or less, and even more preferably 300.00 μm or less. The lower limit of the line width T is preferably 0.50 μm or more, more preferably 1.00 μm or more. If the line width T is within the range described above, the conductive portion 21 can have high conductivity. From the viewpoint of conductivity, the thickness of the wiring M1 can be set to 0.01 μm or more and 200.00 μm or less. 00 μm or less is more preferable, and 5.00 μm or less is particularly preferable. The lower limit of the thickness of the wiring M1 is preferably 0.01 μm or more, more preferably 0.10 μm or more, and even more preferably 0.5 μm or more.

The sheet resistance of the conductive film 13 is preferably 0.05 Ω/square or more and 10.00 Ω/square or less, more preferably 0.20 Ω/square or more and 3.00 Ω/square or less. As described above, the conductive film 13 has a low sheet resistance of 10.00Ω/□ or less, so that it has a high heater performance with a large amount of heat generation under the condition that the voltage is limited, and a high electromagnetic wave transmittance. have. Moreover, since the conductive film 13 has a resistance value of 0.20Ω/□ or more, it has a high heater performance with a large amount of heat generation even under the condition of current limitation.

As shown in FIG. 4, the non-conductive portion 22 is configured by connecting one end portions of four unit units U1 each having a rectangular shape with a connection point C1 at the center of the cross shape. there is These four unit units U1 extend from the connecting point C1 in different directions of +X direction, -X direction, +Y direction and -Y direction. In addition, the direction in which the line segment K1 connecting the connecting points C1 of the two closest non-conductive portions 22 among the plurality of non-conductive portions 22 extends is the same as the direction in which the unit unit U1 of the plurality of non-conductive portions 22 extends. . For example, the line segment K1 shown in FIG. 4 extends parallel to the X direction, and the direction in which the line segment K1 extends is the +X direction or the -X direction, which is the direction in which two of the four unit units U1 extend. Same as direction.

In the example of FIG. 4, each of the four unit units U1 included in the non-conductive portion 22 has a rectangular shape with a length L1 in the long side direction and a width L2 in the short side direction. have. In addition, the non-conductive portion 22 has a length L3 twice as long as the length L1 of the unit unit U1 in the X direction and the Y direction.

Here, the non-conductive portion 22 is for transmitting electromagnetic waves in a specific frequency band corresponding to its size, ie width L2 and length L3 (length L1). Therefore, the size of the non-conductive portion 22 is designed according to the frequency band of the electromagnetic wave that is to be transmitted through the non-conductive portion 22 . For example, when transmitting an electromagnetic wave in a so-called millimeter wave frequency band centered at 76.5 GHz through the non-conductive portion 22, for example, the width L2 is designed to be 280 μm and the length L3 is designed to be 1400 μm. can be done. However, since it also depends on the positional relationship of the plurality of non-conductive portions 22, the width L2 and the length L3 can be adjusted as appropriate.
Since the non-conductive portion 22 is formed in the conductive film 13 in this manner, the conductive film 13 allows electromagnetic waves having a specific frequency band to pass therethrough.

In the conductive film 13, two non-conductive portions 22 adjacent to each other are arranged such that the connecting points C1 are adjacent to each other on a straight line in the direction in which the unit U1 extends. Here, in order for the connection points C1 to be adjacent to each other on a straight line in the direction in which the unit U1 extends, the line segment connecting the two adjacent connection points C1 and the center line of the unit U1 extending from one of the connection points C1 and the angle formed by the line segment connecting two adjacent connecting points C1 and the center line of the unit U1 extending from the other connecting point C1 are both within the angle range of 0° to 15°. To fit, the contiguous connection point C1 is included.

In the example of FIG. 4, of the two left and right non-conductive portions 22 adjacent to each other in the X direction, the +X direction, which is the direction in which one of the four unit units U1 constituting the left non-conductive portion 22 extends, and the right side The connecting point C1 of the left non-conductive portion 22 and the connecting point C1 of the right non-conductive portion 22 are aligned along the −X direction, which is the direction in which one of the four unit units U1 constituting the non-conductive portion 22 extends. adjacent to the line. In this example, the angle formed by the line segment connecting the two adjacent connection points C1 and the center line of the unit unit U1 extending from one of the connection points C1, and the angle between the line segment connecting the two adjacent connection points C1 All the angles formed with the center line of the unit U1 extending from the other connection point C1 are 0°.

Also, the unit units U1 of these two non-conductive portions 22 that are closest to each other extend in directions facing each other. In the example shown in FIG. 4, for example, the unit unit U1 extending in the +X direction of the left non-conductive portion 22 and the unit unit U1 extending in the -X direction of the right non-conductive portion 22 face each other. extending in the direction Here, two unit units U1 extending in directions facing each other means that the angle between the direction in which one unit unit U1 extends and the direction in which the other unit unit U1 extends is such that the directions are parallel to each other. Assuming that one case is 180°, it means that two unit units U1 extend in respective directions within a range of 165° to 180°.

Also, the conductive portion 21 is located between two non-conductive portions 22 having connection points C1 adjacent to each other in the direction in which the unit units U1 extend, and the unit unit U1 closest to each other of the two non-conductive portions 22. It has a constricted conductive region R1 positioned between and a peripheral conductive region R2 which is a region other than the constricted conductive region R1. In the example of FIG. 4, the constricted conductive region R1 includes, for example, a unit unit U1 extending in the +X direction from the connection point C1 in the left non-conductive portion 22, and a unit unit U1 extending in the +X direction from the connection point C1 in the right non-conductive portion 22. It consists of one unit cell A1 located between the unit units U1 extending toward.

In addition, the plurality of wirings M1 forming the conductive portion 21 has an auxiliary wiring S1 inside the unit cell A1 included in the constricted conductive region R1. The auxiliary wiring S1 divides the unit cell A1 into two by connecting both ends to the wiring M1 forming the outline of the unit cell A1.

As described above, the constricted conductive region R1 includes a plurality of wirings M1 forming the outline of the unit cell A1 and the auxiliary wirings S1 arranged in the unit cell A1. The density is higher than the wiring density in the peripheral conductive region R2. Here, the wiring density is defined by the volume of the wiring M1 per unit area of the conductive film 13, for example.

Here, for example, as shown in FIG. 5, consider a conductive film 33 in which the constricted conductive region R1 does not include the auxiliary wiring S1 and the wiring density in the constricted conductive region R1 and the wiring density in the peripheral conductive region R2 are equal to each other. When a current is passed through the conductive film 33 in the +Y direction, for example, the current flows through the conductive portion 21, but the number of wirings M1 forming the constricted conductive region R1 is greater than the number of the wirings M1 forming the peripheral conductive region R2. Since the number of wirings M1 is small, current flows intensively in the constricted conductive region R1. Due to such concentration of current, heat is locally generated in the constricted conductive region R1, and the plurality of wirings M1 forming the constricted conductive region R1 may deteriorate.

In the conductive film 13 according to the first embodiment of the present invention, since the wiring density in the constricted conductive region R1 is higher than that in the peripheral conductive region R2, the concentration of current in the constricted conductive region R1 is suppressed and the constricted conductive region R1 is suppressed from deteriorating due to local heat generation.

Further, the present inventors have surprisingly found that the conductive film 13 according to the first embodiment of the present invention, in which the wiring density in the constricted conductive region R1 is higher than the wiring density in the peripheral conductive region R2, Compared to the conductive film 33 shown in FIG. 5 in which the wiring density and the wiring density in the peripheral conductive region R2 are the same, the transmittance of electromagnetic waves in a specific frequency band corresponding to the size of the plurality of non-conductive portions 22 is further improved. found to do.

As described above, according to the conducting member 11 according to the first embodiment of the present invention, the wiring density in the constricted conductive region R1 of the conductive portion 21 is higher than the wiring density in the peripheral conductive region R2. Local deterioration due to heat generation can be suppressed while transmitting electromagnetic waves in a specific frequency band corresponding to the size.

Further, although not shown, a heater can be configured by the current-carrying member 11 according to the first embodiment of the present invention and a power supply device for applying a voltage to the conductive film 13 of the current-carrying member 11 . This heater is particularly useful when it is arranged so as to cover sensors and communication equipment that use electromagnetic waves such as so-called millimeter waves and microwaves, which are installed in automobiles and the like.

For example, it is known that erroneous detection in sensors or communication failure in communication devices tends to occur when snow or ice builds up around sensors, communication devices, and the like.

According to the heater provided with the current-carrying member 11 according to the first embodiment of the present invention, it is possible to remove snow or ice build-up on the heater, and the frequency band corresponding to the size of the plurality of non-conductive portions 22 in the current-carrying member 11 can be removed. of electromagnetic waves can be transmitted, the influence of snow or ice accretion can be suppressed, and erroneous detection, communication failure, or the like in sensors or communication devices can be suppressed. Furthermore, since this heater includes the current-carrying member 11 according to the first embodiment of the present invention, the occurrence of local deterioration of the conductive film 13 due to heat generation is also suppressed, so that the heater is excellent in durability.

Although FIG. 4 shows an example in which the constricted conductive region R1 is composed of one unit cell A1, the constricted conductive region R1 may be composed of two or more unit cells A1. FIG. 6 shows an example in which the constricted conductive region R1 is composed of two unit cells A1. In this example, each of the two unit cells A1 forming the constricted conductive region R1 includes the auxiliary wiring S1, but only one of the unit cells A1 may include the auxiliary wiring S1. Even in this case, since the wiring density in the constricted conductive region R1 is higher than the wiring density in the peripheral conductive region R2, the conductive member 11 transmits electromagnetic waves in a specific frequency band corresponding to the size of the plurality of non-conductive portions 22. However, local deterioration due to heat generation can be suppressed.

Thus, when the constricted conductive region R1 is composed of a plurality of unit cells A1, at least one of the plurality of unit cells A1 forming the constricted conductive region R1 can include the auxiliary wiring S1.

In addition, in order to maintain the transmittance of electromagnetic waves in a specific frequency band corresponding to the size of the plurality of non-conductive portions 22 in the current-carrying member 11, the two non-conductive portions 22 whose connection points C1 are closest to each other are located closest to each other. The distance F1 between adjacent unit units U1 is preferably shorter than twice the length L1 of unit unit U1.

In addition, in order to suppress current concentration in the constricted conductive region R1 and maintain the transmittance of electromagnetic waves in a specific frequency band corresponding to the size of the plurality of non-conductive portions 22 in the current-carrying member 11, For example, as shown in FIG. 7, the distance F1 between the unit units closest to each other in the two non-conductive portions 22 to which C1 is closest is 0.3 times or more the length L1 of the unit unit U1. is 0.6 times or less of the length L1, that is, it is particularly preferable to satisfy the following inequality (1).
0.3×L1≦F1≦0.6×L1 (1)

In the example of FIG. 7, the unit unit U1 has a mesh pitch E of a plurality of wires M1, that is, a length L1 that is 3.5 times the width of the unit cell A1. Also, the distance F1 between the two non-conductive portions 22 whose connecting points C1 are closest to each other is equal to twice the width of the unit cell A1. Therefore, F1=2/3.5*L1≈0.57*L1, and the distance F1 satisfies the inequality (1).

Further, from the viewpoint of suppressing current concentration in the constricted conductive region R1, the auxiliary wiring S1 arranged in the constricted conductive region R1 preferably extends along the direction of the current flowing through the constricted conductive region R1. For example, as shown in FIG. 8, when the direction in which the current J flows is determined to be the +Y direction, the conductive films have the same potential in the X direction. Except for the auxiliary wiring S1 arranged between the adjacent non-conductive portions 22 and extending along the X direction, the auxiliary wiring S1 arranged between the non-conductive portions 22 adjacent to each other in the X direction and extending along the Y direction. can be left. Even in this case, since the wiring density in the constricted conductive region R1 is higher than the wiring density in the peripheral conductive region R2, even though the electromagnetic waves in a specific frequency band corresponding to the size of the plurality of non-conductive portions 22 are transmitted, localized heat generation due to heat generation deterioration can be suppressed.

Also, the unit cell A1 in the constricted conductive region R1 can include a plurality of auxiliary wirings S1, as shown in FIG. 9, for example. In the example of FIG. 9, the unit cell A1 in the constricted conductive region R1 includes three auxiliary wirings S1. Thus, even when the unit cell A1 in the constricted conductive region R1 includes a plurality of auxiliary wirings S1, the wiring density in the constricted conductive region R1 is higher than that in the peripheral conductive region R2. Local deterioration due to heat generation can be suppressed while transmitting electromagnetic waves in a specific frequency band corresponding to the size.

Further, as shown in FIG. 10, the unit cell A1 in the constricted conductive region R1 can also include a plurality of auxiliary wirings S1 arranged so as to intersect each other. In the example of this figure, one unit cell A1 forming the constricted conductive region R1 includes two auxiliary wirings S1 orthogonal to each other. Even in such a case, since the wiring density in the constricted conductive region R1 is higher than the wiring density in the peripheral conductive region R2, it is possible to generate heat while transmitting electromagnetic waves in a specific frequency band corresponding to the size of the plurality of non-conductive portions 22. can suppress local deterioration due to

In addition, although FIG. 1 shows that the conductive film 13 has a shape along a plane, it can also have a shape along a curved surface. For example, by forming the conductive film 13 on the substrate 12 having a curved surface, the conductive film 13 can be formed to have a shape that follows the curved shape of the substrate 12 . The curved shape includes, for example, a shape along the surface of any three-dimensional shape such as a sphere, a cylinder, and a cone.

Moreover, the conductive film 13 can also have a shape along the surface of a more complicated three-dimensional shape. Complex solids include, for example, automobile emblems, radar radomes, radar front covers, automobile headlamp covers, antennas, or reflectors. By arranging the conducting member 11 according to the embodiment of the present invention along such a three-dimensional shape, for example, the conducting member 11 can be arranged along the emblem of an automobile and a radar can be mounted inside the emblem. is possible.

In addition, when it is desired to make the design of the member covered by the conducting member 11 visible to an outside observer, such as when the conducting member 11 is arranged along the emblem of the automobile, the conducting member 11 has transparency. is desirable. In such a case, in order to make the presence of the plurality of wirings M1 inconspicuous, the upper limit of the mesh pitch E of the plurality of wirings M1 is preferably 800.00 μm or less, more preferably 600.00 μm or less, and 400.00 μm or less. 00 μm or less is more preferable. Moreover, the lower limit of the mesh pitch E is preferably 5.00 μm or more, more preferably 30.00 μm or more, and even more preferably 80.00 μm or more.

In addition, since the conductive member 11 has a visible light transmittance of 75.0% or more, the opening ratio of the mesh shape formed by the plurality of wirings M1 is preferably 75% or more, and is 80% or more. is more preferable. Here, the aperture ratio of the mesh shape means the ratio of the transparent portion excluding the wiring M1 to the area occupied by the mesh shape portion. It corresponds to the proportion of the total area occupied by A1.

The shape of the unit cell A1 is not particularly limited. ) Geometric figures combining (regular) polygons such as octagons, circles, ellipses, stars and the like can also be used.

Further, it is explained that the size of the unit unit U1 of the non-conductive portion 22 is designed according to the frequency band of the electromagnetic wave that is to be transmitted through the non-conductive portion 22. FIG. For example, in order to transmit electromagnetic waves in the millimeter wave frequency band centered at 76.5 GHz, the length L1 of the unit unit U1 in the direction in which the unit unit U1 extends can be designed to be 700 μm. In the present invention, for example, this length L1 can be designed to be 0.1 mm or more, that is, 100.0 μm or more and 1000.0 mm or less.

Further, although it has been described that the non-conductive portion 22 is composed of four unit units U1, it may be composed of two unit units, three unit units, or five unit units. It can also be configured by the unit units described above.

Also, although the unit unit U1 of the non-conductive portion 22 is described as having a rectangular shape, the shape of the unit unit U1 is not particularly limited to a rectangle as long as it is elongated. For example, unit U1 can have an elliptical shape or the like.

In addition, the cross-shaped edge G1 of the non-conductive portion 22 is formed as part of a plurality of wirings M1 forming a regular mesh shape, but separately from these wirings M1, that is, these wirings It may be formed at a position shifted from M1. However, in this case, the edge G1 must be electrically connected to the wiring M1.

The four unit units U1 of the non-conductive portion 22 extend in the same direction as the multiple wirings M1. may be different from each other. However, when the direction in which the four unit units U1 extend and the direction in which the plurality of wirings M1 extend are the same, the presence of the cross-shaped non-conductive portion 22 is less noticeable when the current-carrying member 11 is viewed. Therefore, for example, when transparency is required for the conductive member 11, the direction in which the four unit units U1 extend and the direction in which the plurality of wirings M1 extend are the same from the viewpoint that the presence of the non-conductive portion 22 is inconspicuous. is preferable.

Also, although not shown, a conductive dummy wiring that is not electrically connected to the edge G1 can be arranged inside the non-conductive portion 22 . However, the dummy wiring is preferably shorter than the length L1 of the unit U1 so as not to interfere with electromagnetic waves.

Embodiment 2
In Embodiment 1, the plurality of non-conductive portions 22 are arranged in the X direction and the Y direction so that the pair of non-conductive portions 22 adjacent in the X direction and the pair of non-conductive portions 22 adjacent in the Y direction are closest to each other. Although it is described that they are arranged along the Y direction, the arrangement of the plurality of non-conductive portions 22 is not particularly limited to this.

FIG. 11 shows a partial plan view of the conductive film 13A in the second embodiment. The plurality of non-conductive portions 22 are alternately arranged such that two non-conductive portions 22 closest to each other are shifted by a pattern pitch P1 in the Y direction and by a pattern pitch P2 in the X direction. Since the plurality of non-conductive portions 22 are arranged in a staggered manner in this way, they are arranged along the Y direction at intervals of the pattern pitch Q1 having a length twice as long as the pattern pitch P1, and along the X direction. are arranged at intervals of a pattern pitch Q2 having a length twice as long as the pattern pitch P2.

Here, the pattern pitch P1 indicates the distance in the Y direction between the connecting points C1 of the two non-conductive portions 22 that are closest to each other, and the pattern pitch P2 is the connecting point C1 of the two non-conductive portions 22 that are closest to each other. indicates the distance in the X direction between In addition, the pattern pitch Q1 indicates the distance between the connecting points C1 of two non-conductive portions 22 arranged adjacent to each other along the Y direction, and the pattern pitch Q2 indicates the distance between the connection points C1 of two adjacent non-conductive portions 22 arranged along the X direction. The distance between the connection points C1 of the two non-conductive portions 22 is shown.

Further, the direction in which the line segment K2 connecting the connecting points C1 of the two closest non-conductive portions 22 among the plurality of non-conductive portions 22 extends is the direction in which the four unit units U1 of each of the plurality of non-conductive portions 22 extend. , that is, the +Y direction, the −Y direction, the +X direction and the −X direction. Also, the four unit units U1 each have a length L1.

FIG. 12 shows an enlarged view of four unitary units U2, U3, U4 and U5 adjacent to each other in the X and Y directions. The four unitary units U2, U3, U4 and U5 are equivalent to the unitary unit U1 in FIG. 11, but are denoted as unitary units U2, U3, U4 and U5 for ease of explanation.

Conductive portion 21, as shown in FIG. 12, has two non-conductive portions 22A and 22B having connection points C2 and C3 that are adjacent to each other on a straight line in the direction in which unit units U2 and U3 extend (+X direction and −X direction). between and between unit units U2 and U3 closest to each other of those two non-conductive portions 22A and 22B, and on a straight line in the direction in which unit units U4 and U5 extend (+Y direction and −Y direction) A cross located between two non-conductive portions 22C and 22D having connection points C4 and C5 adjacent to each other and between unitary units U4 and U5 closest to each other of those two non-conductive portions 22C and 22D. It has a constricted conductive region R1 shaped. The conductive portion 21 also has a peripheral conductive region R2, which is not shown in FIG. 12 but is a region other than the constricted conductive region R1.

The cross-shaped constricted conductive region R1 shown in FIG. 12 is composed of five unit cells A1. Wires S2 and S3 are included.

The orientation of the auxiliary wirings S2 and S3 is not particularly limited, but by arranging them in the orientation shown in FIG. Concentration of the current J can be further suppressed.

Since the constricted conductive region R1 includes the auxiliary wiring S1 in this way, the wiring density of the constricted conductive region R1 becomes higher than the wiring density of the peripheral conductive region R2. According to the conducting member of the second embodiment, concentration of the current J in the constricted conductive region R1 can be suppressed, and deterioration of the plurality of wirings M1 in the constricted conductive region R1 can be suppressed.

In addition, the present inventors also found that the current-carrying member according to the second embodiment is similar to the current-carrying member 11 of the first embodiment, compared with the case where the auxiliary wiring S1 is not present in the constricted conductive region R1. It has been found that the transmittance of electromagnetic waves in a specific frequency band corresponding to the size of the plurality of non-conductive portions 22 is improved.

As described above, according to the current-carrying member of the second embodiment of the present invention, as with the current-carrying member 11 of the first embodiment, while transmitting electromagnetic waves in a specific frequency band corresponding to the size of the plurality of non-conductive portions 22, Also, local deterioration due to heat generation can be suppressed.

In addition, in order to maintain the transmittance of electromagnetic waves in a specific frequency band corresponding to the size of the plurality of non-conductive portions 22 in the conductive member of Embodiment 2, the direction in which the unit units U2 and U3 extend (+X direction and −X direction The distance F2 between unit units U2 and U3 of two non-conductive portions 22A and 22B that are closest to each other in the direction ) is similar to the distance F1 between ends T1 and T2 in the first embodiment. and less than twice the length L1 of U3. Also, the distance F3 between unit units U4 and U5 closest to each other in two non-conductive portions 22C and 22D adjacent in the direction in which unit units U4 and U5 extend (+Y direction and −Y direction) is the same as distance F1. Therefore, it is preferably shorter than twice the length L1 of the units U4 and U5.

In the example shown in FIG. 12, of the five unit cells A1 forming the constricted conductive region R1, one unit cell A1 arranged in the center of the cross shape includes two auxiliary wirings S2 and S3. However, the unit cell A1 may include only one of the auxiliary wirings S2 and S3, or may include three or more auxiliary wirings. Also, at least one auxiliary wiring may be included in at least one unit cell A1 among the five unit cells A1 forming the constricted conductive region R1. Further, the auxiliary wirings S2 and S3 may not be arranged only within one unit cell A1, and may be arranged across a plurality of unit cells A1.

Below, each member which constitutes current-carrying member 11 of Embodiment 1 will be described in detail. Note that the following description also applies to each member of the current-carrying member of the second embodiment.

<Substrate>
The substrate 12 is not particularly limited as long as it has insulating properties and can support at least the conductive film 13, but is preferably transparent and preferably made of a resin material.
Specific examples of the resin material forming the substrate 12 include polymethyl methacrylate (PMMA), acrylonitrile butadiene styrene (ABS), polyethylene terephthalate (PET), and polycarbonate (PC). ), polycycloolefin, (meth) acrylic, polyethylene naphthalate (PEN), polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC) ), Polyvinylidene chloride (PVDC), Polyvinylidene difluoride (PVDF), Polyarylate (PAR), Polyethersulfone (PES), Polymer acrylic, Fluorene derivative, Crystalline cyclo Olefin polymer (Cyclo Olefin Polymer: COP), triacetyl cellulose (TAC) and the like can be mentioned.

Here, from the viewpoint of the transparency and durability of the substrate 12, the substrate 12 is preferably composed mainly of any one of polymethyl methacrylate resin, polycarbonate resin, acrylonitrile-butadiene-styrene resin, and polyethylene terephthalate resin. . Here, the main component of the substrate 12 means that it occupies 80% or more of the constituent components of the substrate 12 .

The visible light transmittance of the substrate 12 is preferably 85.0% to 100.0%.
The thickness of the substrate 12 is not particularly limited, but is preferably 0.05 mm or more and 2.00 mm or less, and more preferably 0.10 mm or more and 1.00 mm or less, from the viewpoint of handleability.

<Primer layer>
A primer layer may be provided between the substrate 12 and the conductive film 13 in order to firmly support the conductive film 13 . The material of the primer layer is not limited as long as it can firmly support the conductive film 13, but when the conductive film 13 is formed of a plurality of wirings M1, it is preferably made of a urethane-based resin material.

<Wiring>
The wiring M1 is made of a conductive material. A metal, a metal oxide, a carbon material, a conductive polymer, or the like can be used as the wiring M1. For example, when the wiring M1 is made of metal, the type of metal is not particularly limited, and examples thereof include copper, silver, aluminum, chromium, lead, nickel, gold, tin, and zinc. From the viewpoint of conductivity, copper, silver, aluminum and gold are more preferable. As a method for forming the metallic wiring M1, a semi-additive method, a full-additive method, a subtractive method, a silver salt method, printing of a metal-containing ink or its precursor, an inkjet method, and a laser direct structuring method can be used. , and combinations of these may also be used. A bulk material can be used as the metal, and nanowires and nanoparticles can also be used. When the wiring M1 is made of a carbon material, the wiring M1 is not particularly limited in structure or composition, but carbon nanotubes, fullerenes, carbon nanobuds, graphene, graphite, and the like can be used. When the wiring M1 is made of metal oxide, ITO (Indium Tin Oxide) can be used as the wiring M1. When the wiring M1 is made of a conductive polymer, PEDOT-PSS (poly(3,4-ethylenedioxythiophene) polystyrene sulfonate) or the like can be used as the wiring M1.

The present invention will be described in more detail below based on examples. The materials, amounts used, proportions, processing details, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention, and the scope of the present invention is limited by the following examples. not to be interpreted.

<Example 1>
(Preparation of substrate)
A polycarbonate resin film (PANLITE PC-2151 manufactured by Teijin) having a thickness of 250.0 μm was prepared as a substrate.

(Preparation of composition for forming primer layer)
The following components were mixed to obtain a composition for forming a primer layer.
Z913-3 (manufactured by Aica Kogyo Co., Ltd.) 33 parts by mass IPA (isopropyl alcohol) 67 parts by mass

(Formation of primer layer)
The obtained composition for forming a primer layer was bar-coated on a substrate so as to have an average dry film thickness of 0.5 μm, and dried at 80° C. for 3 minutes. After that, the formed layer of the composition for forming a primer layer was irradiated with ultraviolet rays (UV) at an irradiation dose of 1000 mJ to form a primer layer having a thickness of 0.4 μm.

(Preparation of composition for forming precursor layer of plated layer)
The following components were mixed to obtain a composition for forming a precursor layer for a plating layer.
IPA (isopropyl alcohol) 38.00 parts by mass Polybutadiene maleic acid 4.00 parts by mass FOM-03008 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) 1.00 parts by mass IRGACURE OXE02 (manufactured by BASF, ClogP = 6.55)
0.05 part by mass Note that FOM-03008 contains a compound represented by the following chemical formula as a main component.

(Preparation of substrate with precursor layer to be plated)
The obtained composition for forming a precursor layer of a layer to be plated was bar-coated on the primer layer so as to have a film thickness of 0.2 μm, and dried in an atmosphere of 120° C. for 1 minute. Immediately thereafter, a 12.0 μm-thick polypropylene film was laminated on the composition for forming the precursor layer of the layer to be plated, thereby producing a substrate with a precursor layer to be plated.

(Preparation of substrate with layer to be plated)
A conductive portion 21 having a width of 110.804 mm in the Y direction, a width of 100.804 mm in the X direction, a thickness of 6.00 mm, and formed of a plurality of wirings M1 shown in FIG. and a pair of electrode pads (not shown) arranged at both ends in the Y direction. In this photomask, a plurality of non-conductive portions 22 are arranged along the X direction and the Y direction. , and the unit cells A1 located between the most adjacent unit units U1 of the non-conductive portions 22 adjacent to each other in the Y direction constitute the constricted conductive region R1 of the conductive portion 21 . In addition, one auxiliary wiring S1 is arranged in this constricted conductive region R1.

The line width of the exposure pattern corresponding to the line width W of the wiring M1 was 0.004 mm, and the interval between the exposure patterns corresponding to the mesh pitch E of the wiring M1 adjacent to each other in the X and Y directions was 0.280 mm. rice field. The width of the exposure pattern corresponding to the width L2 of the unit U1 was 0.280 mm, the same as the interval between the exposure patterns corresponding to the wirings M1 adjacent to each other. The length of the exposure pattern corresponding to the length L1 of the unit U1 was 0.700 mm, and the width of the exposure pattern corresponding to the length L3 of the non-conductive portion 22 was 1.400 mm. The exposure pattern distance corresponding to the distance F1 between the closest unit units U1 of the two non-conductive portions 22 having the connecting points C1 adjacent to each other on a straight line in the X direction and the Y direction is equal to the mesh pitch E, which is 0. .280 mm. Also, the distance of the exposure pattern corresponding to the distance between the connecting points C1 adjacent to each other on a straight line in the X direction and the Y direction was 1.680 mm, which is six times the mesh pitch E.

Below, the distance F1 between the closest unit units U1 of the two non-conductive portions 22 having connecting points C1 that are adjacent to each other on a straight line in the X and Y directions is defined as the gap pitch, A distance between connecting points C1 adjacent on a line is sometimes called a pattern pitch.

In addition, in this photomask, 59 regions each having a width of 1.680 mm in the X direction and the Y direction including one non-conductive portion 22 in the central portion are arranged in the X direction and the Y direction. An exposure pattern is formed. Therefore, the photomask is formed with an exposure pattern corresponding to 59×59=3481 non-conductive portions 22 .

This photomask was used to irradiate the substrate with the layer-to-be-plated precursor layer with ultraviolet rays (energy amount: 200 mJ/cm ² , wavelength: 365 nm) through the film mask. Next, the substrate with the layer-to-be-plated precursor layer after being irradiated with the ultraviolet rays was developed by showering pure water for 5 minutes to produce a substrate with the layer-to-be-plated.

(Formation of conductive film)
The substrate with the layer to be plated was immersed in a 1% by mass sodium hydrogen carbonate aqueous solution at 35° C. for 5 minutes. Next, the substrate with the layer to be plated was immersed in a 55° C. palladium catalyst application liquid RONAMERSE SMT (manufactured by Rohm and Haas Electronic Materials Co., Ltd.) for 5 minutes. After the substrate with the layer to be plated was washed with water, it was continuously immersed in CIRCUPOSIT6540 (manufactured by Rohm and Haas Electronic Materials Co., Ltd.) at 35° C. for 5 minutes, and then washed with water again. Further, the substrate with the layer to be plated was immersed in CIRCUPOSIT 4500 (manufactured by Rohm and Haas Electronic Materials Co., Ltd.) at 45° C. for 20 minutes and then washed with water to form a conductive film on the layer to be plated. As a result, a conductive portion 21, a plurality of non-conductive portions 22, and a plurality of non-conductive portions 22 as shown in FIG. Thus, a current-carrying member of Example 1 having a conductive film made of copper and having electrode pads (not shown) formed thereon was obtained. The pair of electrode pads are electrically connected to the conductive portion 21, respectively.

The conductive member of Example 1 is cut, for example, along the width direction of the wiring extending along the Y direction, that is, along a plane parallel to the XZ plane, and the cross section of the wiring is photographed with an optical microscope. When the thickness was measured, the wiring had a thickness of 0.003 mm. Further, when the wiring was observed with an optical microscope, the line width W was 0.010 mm.

Also, as shown in FIG. 13, the area of the constricted conductive region R1 is defined as the area of the portion surrounded by the center line CL of the four wirings M1 forming the outline of one unit cell A1, which is the constricted conductive region R1. The sum of the volumes of the plurality of wirings M1 in the portion surrounded by these four center lines CL was calculated as the volume of the plurality of wirings M1 in the constricted conductive region R1. In this case, the area of the constricted conductive region R1 is calculated by (mesh pitch E)×(mesh pitch E). Also, the volume of the plurality of wirings M1 in the constricted conductive region R1 is calculated by [3×(mesh pitch E)−2×(line width W)]×(line width W)×(thickness of wiring M1).

The area of the constricted conductive region R1 calculated in this manner was approximately 0.078 mm ² , and the volume of the plurality of wirings M1 in the constricted conductive region R1 was approximately 2.460×10 ⁻⁵ mm ³ . Therefore, the wiring density of the constricted conductive region R1 was (volume of the plurality of wirings M1 in the constricted conductive region R1)/(area of the constricted conductive region R1)=0.314×10 ⁻³ mm.

Further, since the structure obtained by removing the auxiliary wiring S1 from the constricted conductive region R1 is the same as the structure of the unit cell A1 constituting the peripheral conductive region R2, the region obtained by removing the auxiliary wiring S1 from the constricted conductive region R1 is referred to as the peripheral conductive region R2. , the area of the unit cell A1 forming the peripheral conductive region R2 and the volume of the plurality of wires M1 in the unit cell A1 forming the peripheral conductive region R2 were calculated. In this case, the area of the unit cells A1 forming the peripheral conductive region R2 is calculated by (mesh pitch E)×(mesh pitch E), like the area of the constricted conductive region R1. In addition, the volume of the plurality of wirings M1 in the unit cell A1 that configures the peripheral conductive region R2 is given by [2×(mesh pitch E)−(line width W)]×(line width W)×(thickness of wiring M1). Calculated.

The area of the unit cell A1 forming the peripheral conductive region R2 calculated in this manner is approximately 0.078 mm ² , and the volume of the multiple wirings M1 in the unit cell A1 forming the peripheral conductive region R2 is approximately 1.650 mm 2 . It was ×10 ⁻⁵ mm ³ . Therefore, the wiring density of the peripheral conductive region R2 is (the volume of the plurality of wirings M1 in the unit cell A1 forming the peripheral conductive region R2)/(the area of the unit cell A1 forming the peripheral conductive region R2)=0.210× It was 10 ⁻³ mm.

Therefore, the ratio of the wiring density of the constricted conductive region R1 to the wiring density of the peripheral conductive region R2 in Example 1 is (wiring density of the constricted conductive region R1)/(wiring density of the peripheral conductive region R2)×100%=149%. Met.

<Example 2>
Instead of using a photomask on which an exposure pattern corresponding to the conductive film 13 shown in FIG. A conductive member of Example 2 was fabricated in the same manner as in Example 1, except that a photomask corresponding to a conductive film in which the constricted conductive region R1 was composed of two unit cells A1 was used.

In the photomask used in Example 2, the size of the exposure pattern corresponding to the non-conductive portion 22 is the same as the size of the exposure pattern corresponding to the non-conductive portion 22 in the photomask used in Example 1. , the distance F1 between the closest unit units U1 of the two non-conductive portions 22 having connecting points C1 adjacent to each other on a straight line in the X direction and the Y direction, that is, the gap pitch is twice the mesh pitch E. The distance between connecting points C1 adjacent to each other on a straight line in the X direction and the Y direction, that is, the pattern pitch was 1.960 mm, which is seven times the mesh pitch E.

In addition, in this photomask, 50 regions each having a width of 1.960 mm in the X direction and the Y direction, including one non-conductive portion 22 in the central portion, were arranged in the X direction and the Y direction. An exposure pattern is formed. Therefore, the photomask is formed with an exposure pattern corresponding to 50×50=2500 non-conductive portions 22 .

Further, by the same method as in Example 1, the area of the portion surrounded by the center line CL of the plurality of wirings M1 forming the outline of the constricted conductive region R1 composed of the two unit cells A1 is reduced to the constricted conductive region R1. and the total volume of the plurality of wirings M1 in the portion surrounded by the plurality of center lines CL was calculated as the volume of the plurality of wirings M1 in the constricted conductive region R1. The area of the constricted conductive region R1 in Example 2 is about 0.157 mm ² , the volume of the plurality of wirings M1 in the constricted conductive region R1 is about 4.920×10 ⁻⁵ mm ³ , and the wiring of the constricted conductive region R1 The density was 0.314×10 ⁻³ mm.

Further, by the same method as in Example 1, the area of the two unit cells A1 forming the peripheral conductive region R2 and adjacent to each other in Example 2, the area of the two unit cells A1 forming the peripheral conductive region R2 and adjacent to each other, , and the wiring density of the peripheral conductive region R2 were calculated. The area of the two unit cells A1 that form the peripheral conductive region R2 and are adjacent to each other in Example 2 is about 0.157 mm ² . The volume of the wiring M1 was about 3.300×10 ⁻⁵ mm ³ and the wiring density of the peripheral conductive region R2 was 0.210×10 ⁻³ mm.

Therefore, the ratio of the wiring density of the constricted conductive region R1 to the wiring density of the peripheral conductive region R2 in Example 2 is (wiring density of the constricted conductive region R1)/(wiring density of the peripheral conductive region R2)×100%=149%. Met.

<Example 3>
Instead of using a photomask on which an exposure pattern corresponding to the conductive film 13 shown in FIG. , except for using a photomask corresponding to a conductive film such that the constricted conductive region R1 sandwiched between two non-conductive portions 22 in the X direction has an auxiliary wiring S1 extending along the Y direction, which is the direction in which the current J flows. produced a current-carrying member of Example 3 in the same manner as in Example 1.

The photomask used in Example 3 is the same as the photomask used in Example 1, except that the constricted conductive region R1 sandwiched between the two non-conductive portions 22 in the Y direction does not include the auxiliary wiring S1. .

Further, the area of the constricted conductive region R1, the volume of the plurality of wirings M1 in the constricted conductive region R1, and the wiring density of the constricted conductive region R1 in the third example were calculated by the same method as in the first example. The area of the constricted conductive region R1 in Example 3 was about 0.078 mm ² . Also, the volume of the plurality of wirings M1 in the constricted conductive region R1 including the auxiliary wiring S1 is approximately 2.460×10 ⁻⁵ mm ³ similar to the volume of the plurality of wirings M1 in the constricted conductive region R1 of the first embodiment. , the volume of the plurality of wirings M1 in the constricted conductive region R1 that does not include the auxiliary wiring S1 is about 1.650×10 ⁻⁵ mm ³ similar to the volume of the plurality of wirings M1 in the peripheral conductive region R2 of the first embodiment. rice field. Since the conductive film of Example 3 has the same number of constricted conductive regions R1 that do not include the auxiliary wiring S1 as the constricted conductive regions R1 that include the auxiliary wiring S1, the volume of the plurality of wirings M1 in the constricted conductive region R1 is , is obtained by calculating the average of the volume of the plurality of wirings M1 in the narrowed conductive region R1 including the auxiliary wiring S1 and the volume of the plurality of wirings M1 in the narrowed conductive region R1 not including the auxiliary wiring S1. The volume of the multiple wirings M1 in the constricted conductive region R1 calculated in this manner was approximately 2.055×10 ⁻⁵ mm ³ . Therefore, the wiring density of the constricted conductive region R1 was 0.262×10 ⁻³ mm.

Further, by the same method as in Example 1, the area of the unit cell A1 forming the peripheral conductive region R2 in Example 3, the volume of the plurality of wirings M1 in the unit cell A1 forming the peripheral conductive region R2, and the peripheral conductive The wiring density of the region R2 was calculated. The area of the unit cell A1 forming the peripheral conductive region R2 in Example 3 is approximately 0.078 mm ² , and the volume of the multiple wirings M1 in the unit cell A1 forming the peripheral conductive region R2 is approximately 1.650×10 ^{− 5} mm ³ and the wiring density of the peripheral conductive region R2 was 0.210×10 ⁻³ mm.

Therefore, the ratio of the wiring density of the constricted conductive region R1 to the wiring density of the peripheral conductive region R2 in Example 3 is (wiring density of the constricted conductive region R1)/(wiring density of the peripheral conductive region R2)×100%=125%. Met.

<Example 4>
Instead of using a photomask on which an exposure pattern corresponding to the conductive film 13 shown in FIG. A conductive member of Example 4 was fabricated in the same manner as in Example 1, except that a photomask corresponding to a conductive film in which two auxiliary wirings S1 orthogonal to each other were included in the constricted conductive region R1 was used. .

The photomask used in Example 3 is the same as the photomask used in Example 1, except that two auxiliary wirings S1 orthogonal to each other are included in the constricted conductive region R1.

Further, the area of the constricted conductive region R1, the volume of the plurality of wirings M1 in the constricted conductive region R1, and the wiring density of the constricted conductive region R1 in the fourth example were calculated by the same method as in the first example. The area of the constricted conductive region R1 in Example 4 is about 0.078 mm ² , the volume of the plurality of wirings M1 in the constricted conductive region R1 is about 3.936×10 ⁻⁵ mm ³ , and the wiring of the constricted conductive region R1 The density was 0.502×10 ⁻³ mm.

Further, by the same method as in Example 1, the area of the unit cell A1 forming the peripheral conductive region R2 in Example 4, the volume of the plurality of wirings M1 in the unit cell A1 forming the peripheral conductive region R2, and the peripheral conductive The wiring density of the region R2 was calculated. The area of the unit cell A1 forming the peripheral conductive region R2 in Example 4 is approximately 0.078 mm ² , and the volume of the multiple wirings M1 in the unit cell A1 forming the peripheral conductive region R2 is approximately 1.650×10 ^{− 5} mm ³ and the wiring density of the peripheral conductive region R2 was 0.210×10 ⁻³ mm.

Therefore, the ratio of the wiring density of the constricted conductive region R1 to the wiring density of the peripheral conductive region R2 in Example 4 is (wiring density of the constricted conductive region R1)/(wiring density of the peripheral conductive region R2)×100%=239%. Met.

<Example 5>
Instead of using a photomask on which an exposure pattern corresponding to the conductive film 13 shown in FIG. A conducting member of Example 5 was produced in the same manner as in Example 1, except that a photomask corresponding to 13A was used. In the photomask used in Example 5, the direction in which the line segment K2 connecting the connecting points C1 of the two non-conductive portions 22 closest to each other among the plurality of non-conductive portions 22 extends, and the four non-conductive portions 22 The exposure patterns corresponding to the plurality of non-conductive portions 22 are arranged such that the directions in which the unit units U1 extend are different from each other.

In the photomask used in Example 5, the line width of the exposure pattern corresponding to the line width W of the wiring M1 is 0.004 mm, corresponding to the mesh pitch E of the wiring M1 adjacent to each other in the X direction and the Y direction. The interval between the exposed patterns was 0.310 mm. The width of the exposure pattern corresponding to the width L2 of the unit U1 was 0.310 mm, the same as the interval between the exposure patterns corresponding to the wirings M1 adjacent to each other. The length of the exposure pattern corresponding to the length L1 of the unit U1 was 0.775 mm, and the width of the exposure pattern corresponding to the length L3 of the non-conductive portion 22 was 1.550 mm. The distance of the exposure pattern corresponding to the distance F2 between the closest unit units U1 of the two non-conductive portions 22 having the connecting points C1 adjacent to each other on a straight line in the X direction and the Y direction, ie, the gap pitch, is the mesh pitch E was 0.930 mm, which is three times the Also, the distances of the exposure patterns corresponding to the distances between connecting points C1 adjacent to each other on a straight line in the X direction and the Y direction, that is, the pattern pitches P2 and Q2 were eight times the mesh pitch E, 2.480 mm.

Further, by the same method as in Example 1, the area of the portion surrounded by the center line CL of the plurality of wirings M1 forming the outline of the cross-shaped narrowed conductive region R1 composed of the five unit cells A1 is narrowed. The area of the conductive region R1 was calculated, and the total volume of the plurality of wirings M1 in the portion surrounded by the plurality of center lines CL was calculated as the volume of the plurality of wirings M1 in the constricted conductive region R1. The area of the constricted conductive region R1 in Example 5 is about 0.288 mm ² , the volume of the plurality of wirings M1 in the constricted conductive region R1 is about 8.030×10 ⁻⁵ mm ³ , and the wiring of the constricted conductive region R1 The density was 0.279×10 ⁻³ mm.

Further, the area of the unit cell A1 forming the peripheral conductive region R2 in Example 5, the volume of the plurality of wirings M1 in the unit cell A1 forming the peripheral conductive region R2, and the peripheral conductive The wiring density of the region R2 was calculated. The area of the unit cell A1 forming the peripheral conductive region R2 in Example 5 is approximately 0.288 mm ² , and the volume of the multiple wirings M1 in the unit cell A1 forming the peripheral conductive region R2 is approximately 5.490×10 ^{− 5} mm ³ and the wiring density of the peripheral conductive region R2 was 0.190×10 ⁻³ mm.

Therefore, the ratio of the wiring density of the constricted conductive region R1 to the wiring density of the peripheral conductive region R2 in Example 5 is (wiring density of the constricted conductive region R1)/(wiring density of the peripheral conductive region R2)×100%=146%. Met.

<Comparative Example 1>
Instead of using a photomask on which an exposure pattern corresponding to the conductive film 13 shown in FIG. A conductive member of Comparative Example 1 was fabricated in the same manner as in Example 1, except that a photomask corresponding to a conductive film that did not include the auxiliary wiring S1 in the constricted conductive region R1 was used.

The photomask used in Comparative Example 1 is the same as the photomask used in Example 1, except that the auxiliary wiring S1 is not included in the constricted conductive region R1.

Further, the area of the constricted conductive region R1 in Comparative Example 1 is approximately 0.078 mm ² , the volume of the plurality of wirings M1 in the constricted conductive region R1 is approximately 1.650×10 ⁻⁵ mm ³ , and the constricted conductive region R1 was 0.210×10 ⁻³ mm. Further, the area of the unit cell A1 in the peripheral conductive region R2 is approximately 0.078 mm ² , the volume of the multiple wirings M1 in the unit cell A1 in the peripheral conductive region R2 is approximately 1.650×10 ⁻⁵ mm ³ , The wiring density in the peripheral conductive region R2 was 0.210×10 ⁻³ mm, which is the same as the wiring density in the narrow conductive region R1. Therefore, the ratio of the wiring density of the constricted conductive region R1 to the wiring density of the peripheral conductive region R2 in Comparative Example 1 is (wiring density of the constricted conductive region R1)/(wiring density of the peripheral conductive region R2)×100%=100%. Met.

<Comparative Example 2>
Instead of using a photomask on which an exposure pattern corresponding to the conductive film 13 shown in FIG. A current-carrying member of Comparative Example 2 was fabricated in the same manner as in Example 1, except that a photomask corresponding to a conductive film that did not include the auxiliary wiring S1 in the constricted conductive region R1 was used.

The photomask used in Comparative Example 2 is the same as the photomask used in Example 2, except that the auxiliary wiring S1 is not included in the constricted conductive region R1.

Further, the area of the constricted conductive region R1 in Comparative Example 2 is approximately 0.157 mm ² , the volume of the plurality of wirings M1 in the constricted conductive region R1 is approximately 3.300×10 ⁻⁵ mm ³ , and the constricted conductive region R1 was 0.210×10 ⁻³ mm. Also, the area of two unit cells A1 adjacent to each other in the peripheral conductive region R2 is approximately 0.157 mm ² , and the volume of the wirings M1 in the two unit cells A1 adjacent to each other in the peripheral conductive region R2 is approximately 3.5 mm 2 . 300×10 ⁻⁵ mm ³ , and the wiring density in the peripheral conductive region R2 was 0.210×10 ⁻³ mm, which is the same as the wiring density in the constricted conductive region R1. Therefore, the ratio of the wiring density of the constricted conductive region R1 to the wiring density of the peripheral conductive region R2 in Comparative Example 2 is (wiring density of the constricted conductive region R1)/(wiring density of the peripheral conductive region R2)×100%=100%. Met.

<Comparative Example 3>
Instead of using a photomask on which an exposure pattern corresponding to the conductive film 13 shown in FIG. A current-carrying member of Comparative Example 2 was fabricated in the same manner as in Example 1, except that a photomask corresponding to a conductive film that did not include the auxiliary wiring S1 in the constricted conductive region R1 was used.

Further, the area of the constricted conductive region R1 in Comparative Example 3 is about 0.288 mm ² , the volume of the plurality of wirings M1 in the constricted conductive region R1 is about 5.490×10 ⁻⁵ mm ³ , and the constricted conductive region R1 was 0.190×10 ⁻³ mm. The area of two unit cells A1 adjacent to each other in the peripheral conductive region R2 is approximately 0.288 mm ² , and the volume of the wirings M1 in the two unit cells A1 adjacent to each other in the peripheral conductive region R2 is approximately 5.5 mm 2 . 490×10 ⁻⁵ mm ³ , and the wiring density in the peripheral conductive region R2 was 0.190×10 ⁻³ mm, which is the same as the wiring density in the constricted conductive region R1. Therefore, the ratio of the wiring density of the constricted conductive region R1 to the wiring density of the peripheral conductive region R2 in Comparative Example 3 is (wiring density of the constricted conductive region R1)/(wiring density of the peripheral conductive region R2)×100%=100%. Met.

The conductive members of Examples 1 to 5 and Comparative Examples 1 to 3 obtained as described above were evaluated as follows.
(millimeter wave transmission evaluation)
A millimeter wave network analyzer (Millimeter Wave Network Analyzers N5290A manufactured by Keysight Technologies) was used to measure the millimeter wave transmittance of a specific wavelength (millimeter wave transmittance) for the current-carrying member. At this time, first, the current-carrying member was attached to a 2 mm thick stainless steel plate having a hole with a diameter of 80 mm. Also, the two ports of the millimeter wave network analyzer were placed facing each other. In addition, the stainless steel plate was placed so that a hole with a diameter of 80 mm in the stainless steel plate was positioned at the midpoint between the two ports, and the surface of the plate-like current-carrying member was perpendicular to the line connecting the two ports. A current-carrying member attached to the As the electromagnetic wave used for the measurement, a polarized wave in which the electric field oscillates in the Y direction of the current-carrying member and the magnetic field oscillates in the X direction of the current-carrying member was used. In this state, the transmittance of millimeter waves of 76.5 GHz with respect to the current-carrying member was measured. At this time, the millimeter-wave transmittance of the current-carrying member was calculated as a percentage, with the case where the millimeter-wave transmittance measured without the current-carrying member placed between the two ports being 100%. A current-carrying member having a measured millimeter-wave transmittance of 85% or more was given an evaluation of A as having excellent transparency to electromagnetic waves, and a measured millimeter-wave transmittance of 80% or more and less than 85%. Evaluation B is given to the current-carrying member as having practically no problem in permeability to electromagnetic waves, and the current-carrying member having a measured millimeter wave transmittance of less than 80% to electromagnetic waves It was decided to attach the evaluation C because it does not have sufficient permeability to the light.

(degradation evaluation)
First, a conductive tape was attached to the entire pair of electrode pads of the current-carrying member. Next, the conductive member was fixed so that the conductive film was perpendicular to the horizontal plane. At this time, no obstacles were placed in the range of 150 mm on both sides of the conductive film. Next, alligator clips connected to a power supply (Kikusui Electronics DME1600; digital multimeter) were attached to the conductive tapes attached to the pair of electrode pads. In this state, the resistance value N1 between the conductive tapes attached to the pair of electrode pads of the conducting member was measured. In addition, the contact resistance via the electrode pad was measured in advance by bonding two conductive tapes to the same electrode pad so as not to contact each other and measuring their resistance. It was confirmed that the contact resistance was 0.05Ω or less and could be sufficiently ignored with respect to the resistance value N1.

After that, the current-carrying member is placed in a constant temperature bath set at a temperature of 25°C, a relative humidity of 60%, and no wind, and a power supply is used to maintain the temperature of the conductive film at 90°C. A voltage was continuously applied to the conductive film for 4000 hours. At this time, the temperature of the conductive film was measured using a thermometer (ETS320 manufactured by FLIR). After 4000 hours have passed since the voltage was applied to the conductive film, the resistance value N2 between the respective conductive tapes attached to the pair of electrode pads was measured, and the deterioration coefficient N2 was obtained from the ratio of the resistance value N2 to the resistance value N1. /N1 was calculated. A current-carrying member having a calculated deterioration coefficient N2/N1 of 1.2 or less was given an evaluation of A because deterioration was greatly suppressed, and the deterioration coefficient N2/N1 was greater than 1.2 and 1.3. For the following current-carrying members, the deterioration is sufficiently suppressed and there is no problem in practical use, and a rating of B is given. A rating of C is given for the fact that deterioration has occurred to some extent that is problematic for practical use, and a rating of D is given for the current-carrying member whose deterioration coefficient N2/N1 is greater than 1.4 for the fact that significant deterioration has occurred. made it

(Visibility evaluation)
Ten observers were placed at a position 1.5 m away from the current-carrying member, and each observer looked at the current-carrying member while holding the current-carrying member over a fluorescent lamp, and the non-conductive portion or the auxiliary wiring was visually recognized. We evaluated whether or not Evaluation A was given for excellent visibility to the current-carrying member, which was evaluated by less than 3 out of 10 observers as visually recognizing the non-conductive part, and 10 observers. 4 or 5 of the observers evaluated that the non-conductive part was visually recognized, and the evaluation B was given as having sufficient visibility. When 5 or more persons evaluated that the non-conductive portion was visually recognized, the current-carrying member was given an evaluation of C.

Table 1 below shows the results of deterioration evaluation and millimeter wave transmission evaluation for Examples 1 to 5 and Comparative Examples 1 to 3. Here, in Table 1, current-carrying members of Examples 1 to 4, Comparative Examples 1 and 2 having patterns as shown in FIGS. 2, 5, 6, 8, 10 and 14 is described as a pattern in which the direction of the line segment connecting the connection points of the closest non-conductive portions is the same as the direction of the unit. In addition, the direction of the line segment connecting the connection points of the nearest non-conductive portions of the conductive member patterns of Example 5 and Comparative Example 3 having patterns as shown in FIGS. 11 and 15 is the direction of the unit. described as a different pattern.

As shown in Table 1, the current-carrying members of Examples 1 to 5 were evaluated as A or B in both the millimeter wave transmission evaluation and the deterioration evaluation, and while having the function of transmitting millimeter waves, they did not conduct electricity to the conductive film. It can be seen that deterioration of the wiring is less likely to occur even if the
In the conductive members of Examples 1 to 5, since the wiring density of the constricted conductive region R1 is higher than the wiring density of the peripheral conductive region R2, the concentration of the current J in the constricted conductive region R1 is suppressed and the wiring is less likely to deteriorate. , and the permeability of millimeter waves is also considered to be improved.

In addition, the current-carrying members of Examples 4 and 5 were rated as A in both the millimeter wave transmission evaluation and the deterioration evaluation, and thus had excellent permeability to millimeter waves, and the deterioration of the wiring was greatly suppressed. In Example 4, the pattern pitch is relatively short at 1.680 mm, and the wiring density ratio is high at 239%. In addition, in Example 5, since the direction of the line segment connecting the connecting points C1 of the nearest non-conductive portions 22 is different from the direction in which the unit unit U1 extends, the distance between the nearest non-conductive portions 22 is compared. This is probably because the path of the current J is relatively short and the path of the current J is relatively wide, and the wiring density of the constricted conductive region R1 is higher than that of the peripheral conductive region R2.

The current-carrying member of Comparative Example 1 was graded B in the millimeter wave transmission evaluation, but was graded D in the deterioration evaluation. In Comparative Example 1, the wiring density of the constricted conductive region R1 and the wiring density of the peripheral conductive region R2 are equal to each other.

The current-carrying member of Comparative Example 2 was C in the millimeter wave transmission evaluation and D in the deterioration evaluation. In Comparative Example 2, the gap pitch is relatively wide at 0.560 mm, and the wiring density of the constricted conductive region R1 and the wiring density of the peripheral conductive region R2 are equal to each other. It is considered that concentration of the current J at is also likely to occur.

The current-carrying member of Comparative Example 3 was graded B in the millimeter wave transmission evaluation, but was graded C in the deterioration evaluation. In Comparative Example 3, the direction of the line segment connecting the connecting points C1 of the nearest non-conductive portions 22 is different from the direction in which the unit unit U1 extends, so the distance between the nearest non-conductive portions 22 is relatively short and Since the path of the current J is relatively wide, the millimeter wave transmission evaluation and deterioration evaluation are superior to those of Comparative Examples 1 and 2, but the wiring density of the constricted conductive region R1 and the wiring density of the peripheral conductive region R2 are equal to each other. Therefore, it is considered that the current J tends to concentrate in the constricted conductive region R1.

Further, the visibility evaluation was A or B in all of Examples 1 to 5 and Comparative Examples 1 to 3, and all current-carrying members had sufficient visibility.

In addition, with respect to the current-carrying member of Examples 1 to 4 having a pattern in which the direction of the line segment connecting the connection point C1 of the closest non-conductive portion 22 is the same as the direction of the unit unit U1, the X direction and the Y direction Focusing on the relationship between the gap pitch and the length L1 of the unit unit U1, that is, the distance F1 between the closest unit units U1 of the two non-conductive portions 22 having the connecting points C1 adjacent to each other on a straight line in Table 2 summarizing the deterioration evaluation and the millimeter wave transmission evaluation is shown below.

From Table 2, in Examples 1, 3 and 4, the gap pitch (distance F1) is 0.3 × L1 or more and 0.6 × L1 or less, so the inequality (1) is satisfied, and in Example 2, the gap pitch Since (distance F1) is greater than 0.6×L1, it can be seen that inequality (2) is not satisfied. Examples 1 to 4 were rated A or B in all of the millimeter wave transmittance evaluation, deterioration evaluation, and visibility evaluation. deterioration is less likely to occur. Focusing on the millimeter wave transmittance evaluation, Examples 1, 3 and 4 that satisfy the inequality (1) are evaluated A, and Example 2 that does not satisfy the inequality (1) is evaluated B. Accordingly, it can be seen that a current-carrying member having excellent millimeter-wave transmittance can be obtained by satisfying the inequality (1).

The present invention is basically configured as described above. Although the current-carrying member of the present invention has been described in detail above, the present invention is not limited to the above-described embodiments, and various improvements and modifications may be made without departing from the gist of the present invention. Of course.

11 current-carrying member 12 substrate 13, 13A, 33 conductive film 21 conductive portion 22, 22A, 22B, 22C, 22D non-conductive portion A1 unit cell C1, C2, C3, C4, C5 connection point CL center Line, E Mesh pitch, F1 Distance, G1 Edge, J Current, K1, K2 Line segment, L1, L3 Length, L2 Width, M1 Wiring, P1, P2, Q1, Q2 Pattern pitch, R1 Constricted conductive region, R2 Peripheral conductive area, S1, S2, S3 auxiliary wiring, U1, U2, U3, U4, U5 unit unit, W line width.

Claims (8)

A current-carrying member having a conductive film formed thereon,
The conductive film has a conductive portion composed of a plurality of wires and a plurality of non-conductive portions arranged to form a regular repeating pattern,
The plurality of non-conductive parts each include a plurality of unitary units having an elongated shape that are connected to each other at a connection point and extend in different directions from the connection point,
Two non-conductive portions adjacent to each other are arranged such that the connection points are adjacent to each other in the direction in which the unit unit extends,
the unit units closest to each other of the two non-conductive portions extend in directions facing each other;
the conductive portion has a constricted conductive region located between the unit units closest to each other of the two non-conductive portions;
The current-carrying member, wherein the wiring density of the wiring in the constricted conductive region is higher than the wiring density of the wiring in the region of the conductive portion other than the constricted conductive region. the plurality of wires form a mesh shape in which a plurality of unit cells are arranged;
the wiring in the constricted conductive region has at least one auxiliary wiring arranged inside the unit cell included in the constricted conductive region;
2. The conducting member according to claim 1, wherein both ends of said auxiliary wiring divide said unit cell by being connected to said wiring forming an outline of said unit cell. 3. The current-carrying member according to claim 2, wherein said auxiliary wiring extends along the direction of current flowing through said constricted conductive region. 4. The current-carrying member according to claim 1, wherein the distance between said closest unit units of said two non-conductive parts is shorter than twice the length of said unit unit. The distance between the closest unit units of the two non-conductive parts is 0.3 times or more the length of the unit unit and 0.6 times or less the length of the unit unit. Item 5. The current-carrying member according to item 4. The non-conductive portion is composed of four unit units,
The current-carrying member according to any one of claims 1 to 5, wherein the four units are connected to each other at the connecting points so as to form a cross shape. The conducting member according to any one of claims 1 to 6, wherein the conductive film has a shape along a curved surface. A heater comprising the conducting member according to any one of claims 1 to 7.

Images