JP6248136B2 - Conductive film and conductive film roll - Google Patents

Description

  The present invention relates to a conductive film and a conductive film roll.

  A conventional conductive film includes a film substrate, a transparent conductor layer formed on each side of the film substrate, and a metal layer formed on each transparent conductor layer (Patent Document 1: Japanese Patent Laid-Open No. 2004-208867). 2011-60146). Such a conductive film is used for a touch panel. At that time, the metal layer and the transparent conductor layer are etched to form a wiring outside the touch input region. Thereby, a touch panel having a narrow frame can be realized. However, when the conductive film is wound into a conductive film roll, there is a problem that adjacent metal layers are pressure-bonded. Crimping (blocking) means that the metal layers adhere to each other under pressure.

JP 2011-60146 A

  An object of the present invention is to realize a conductive film and a conductive film roll in which metal layers of adjacent conductive films are not pressure-bonded.

(1) The conductive film of the present invention includes a film substrate, a first transparent conductor layer laminated on the first surface of the film substrate, and a first metal layer laminated on the first transparent conductor layer. A metal oxide film layer formed on the surface of the first metal layer, a second transparent conductor layer laminated on the second surface of the film substrate, and a second laminated on the second transparent conductor layer A metal layer is provided.
(2) In the conductive film of the present invention, the metal oxide film layer formed on the surface of the first metal layer is composed of an oxide film of the first metal layer.
(3) The conductive film of the present invention further includes a second metal oxide film layer on the surface of the second metal layer.
(4) In the conductive film of the present invention, the metal oxide film layer formed on the surface of the second metal layer is composed of an oxide film of the second metal layer.
(5) In the conductive film of the present invention, the surface resistance value per unit area of either or both of the first metal layer and the second metal layer is 10Ω / □ (ohms per square) or less.
(6) The conductive film roll of the present invention is formed by winding the conductive film into a roll.

  The conductive film roll obtained by the production method of the present invention has a metal oxide film layer on the surface of the first surface of the film substrate. Since the metal oxide film layer has no free electrons, it does not metal bond with the second metal layer on the surface of the second surface of the film substrate. Therefore, the metal oxide film layer on the first surface of the film substrate and the second metal layer on the second surface of the film substrate are not pressure-bonded. By this invention, the electroconductive film and electroconductive film roll which a metal layer does not press-fit were implement | achieved.

  When the conductive film is wound in a roll shape, the metal oxide film layer on the first surface of the film base and the second metal layer on the second surface of the film base are in contact with each other. However, since the metal oxide film layer and the second metal layer are not pressure-bonded, it is not necessary to insert a slip sheet between the conductive film and the roll. (If there is no metal oxide film layer, the first metal layer on the first surface of the film substrate and the second metal layer on the second surface of the film substrate are in contact when the conductive film is wound into a roll. Since the first metal layer and the second metal layer are bonded to each other, there is a high possibility of being crimped.In order to avoid crimping the first metal layer and the second metal layer, a slip sheet is placed between the conductive films. Must be inserted).

Explanatory drawing of the manufacturing method of the electroconductive film roll of this invention Schematic diagram of a conductive film manufactured by the manufacturing method of the present invention

  In the production method of the present invention, the film base material on which the film formation process on the first surface has been completed is conveyed through the film formation apparatus and continuously supplied to the film formation process on the second surface. If the film formation process on the first surface and the film formation process on the second surface are performed separately, the film substrate must be wound once after the film formation process on the first surface is completed. . At this time, there is a high possibility that dust will adhere to the surface of the film substrate. In the manufacturing method of this invention, the film-forming process of the 1st surface of a film base material and the film-forming process of the 2nd surface of a film base material are continuously implemented in the film-forming apparatus. Therefore, in the manufacturing method of the present invention, the possibility that dust is mixed between the stacked layers is low as compared with the case where the film formation process on the first surface and the film formation process on the second surface are performed separately. Therefore, the conductive film roll manufactured by the manufacturing method of the present invention has few defects and good quality. Moreover, since the manufacturing method of this invention does not have the process of winding a film base material into a roll once between the film-forming process of the 1st surface, and the film-forming process of the 2nd surface, High production efficiency.

[Production Method of Conductive Film Roll]
The conductive film and the conductive film roll of the present invention are preferably manufactured by the sputtering apparatus 10 of FIG. The method for producing a conductive film roll of the present invention is preferably carried out by the sputtering apparatus 10 of FIG. Hereinafter, components and materials provided in the sputtering apparatus 10 will be described. The chamber 11 (chamber) is used to maintain a low pressure atmosphere suitable for sputtering. The low pressure atmosphere suitable for sputtering is, for example, an argon gas atmosphere of 0.1 Pa to 1 Pa.

  The first roll 12 is obtained by winding a long film base 13. The film base 13 is a starting material for the manufacturing process and serves as a foundation for subsequent film formation. After the film base 13 is rewound from the first roll 12, the film base 13 is finally wound around the second roll 25 through the film forming steps described below. Since each film forming step is all performed in the sputtering apparatus 10, the film base 13 and the laminated film do not come into contact with the outside air on the way. Therefore, possibility that dust will adhere to the film base material 13 and each laminated film is low.

    The first film forming roll 14 rotates while winding the film substrate 13 around the surface thereof, and moves the film substrate 13 while moving the first transparent conductor layer 29 (FIG. 2) on the first surface of the film substrate 13. ), And is used to continuously form the first metal layer 30 (FIG. 2). The temperature of the roll surface of the first film forming roll 14 can be controlled, and the temperature control range is, for example, 20 ° C. to 250 ° C. The temperature of the film base 13 during film formation is substantially equal to the surface temperature of the first film formation roll 14.

  The first target material 15 is a material for the first transparent conductor layer 29 (FIG. 2). The first target material 15 faces part of the surface of the first film forming roll 14 and is electrically connected to a DC power source (not shown) outside the chamber 11. As the first target material 15, for example, a fired body target containing indium oxide and tin oxide is used. In this case, the first transparent conductor layer 29 (FIG. 2) is an indium tin oxide (ITO) layer.

  The second target material 16 is a material for the first metal layer 30 (FIG. 2). The second target material 16 faces a part of the surface of the first film forming roll 14 and is electrically connected to a DC power source (not shown) outside the chamber 11. The second target material 16 is preferably any one of copper, silver, aluminum, nickel alloy, copper alloy, titanium alloy, and silver alloy, and more preferably copper. When the second target material 16 is copper, the first metal layer 30 (FIG. 2) is a copper layer.

  A part of the chamber 11 is partitioned to form an oxygen atmosphere chamber 17. Oxygen gas is supplied from the oxygen cylinder 18 through the pressure adjusting valve 19, through the oxygen gas introduction pipe 20, and supplied to the oxygen atmosphere chamber 17. The pressure of the oxygen gas in the oxygen atmosphere chamber 17 is, for example, 0.0005 Pa to 1 Pa. In the oxygen atmosphere chamber 17, substantially only oxygen gas exists. Oxygen gas oxidizes the surface of the first metal layer 30 (FIG. 2) on the first surface of the film base 13 to form a metal oxide film layer 31 (FIG. 2).

  The second film forming roll 21 is rotated while winding the film base material 13 around the surface, and the film base material 13 is moved to move the second transparent conductive layer 32 (FIG. 2) on the second surface of the film base material 13. The second metal layer 33 (FIG. 2) is used for continuous film formation. The temperature of the roll surface of the second film forming roll 21 can be controlled, and the temperature control range is, for example, 20 ° C. to 250 ° C. The temperature of the film substrate 13 during film formation is substantially equal to the surface temperature of the second film formation roll 21.

  The third target material 22 is a material for the second transparent conductor layer 32 (FIG. 2). The third target material 22 faces a part of the surface of the second film forming roll 21 and is electrically connected to a DC power source (not shown) outside the chamber 11. As the third target material 22, for example, a fired body target containing indium oxide and tin oxide is used. In this case, the second transparent conductor layer 32 (FIG. 2) is an indium tin oxide (ITO) layer.

  The fourth target material 23 is a material for the second metal layer 33 (FIG. 2). The fourth target material 23 faces a part of the surface of the second film forming roll 21 and is electrically connected to a DC power source (not shown) outside the chamber 11. The fourth target material 23 is preferably copper, silver, aluminum, nickel alloy, copper alloy, titanium alloy, or silver alloy, and more preferably copper. When the fourth target material 23 is copper, the second metal layer 33 (FIG. 2) is a copper layer.

    The first transparent conductor, the first metal, the second transparent conductor, each sputtering region of the second metal, and the region of the oxygen atmosphere chamber 17 are separated by the partition plate 26 and are independent, and a sputtering gas (for example, Argon gas) and oxygen gas are confined in their respective regions. Therefore, oxygen gas does not enter the adjacent sputtering region. Further, the sputtering gas does not enter the region of the oxygen atmosphere chamber 17.

  A plurality of guide rolls 24 arranged at appropriate positions are used to transport the film substrate 13 through the chamber 11. The second roll 25 is obtained by winding the film base material 13 (that is, the conductive film 35) in which all film formation has been completed into a roll shape. Next, the manufacturing method of this invention is demonstrated in order of a process.

  First, the first transparent conductor layer 29 (FIG. 2) is formed on the first surface of the film substrate 13. While the long film substrate 13 is rewound from the first roll 12, it is transported through the chamber 11 and wound around the first film-forming roll 14, and the first film-forming roll 14 is rotated to continuously make the first transparent conductive material. The body layer 29 (FIG. 2) is moved to the film forming position. When the first transparent conductor layer 29 (FIG. 2) is formed by sputtering, a DC voltage is applied between the first film forming roll 14 and the first target material 15 to generate, for example, argon plasma. The DC voltage is, for example, 0V for the first film forming roll 14 and -400V to -100V for the first target material 15. Argon ions collide with the first target material 15, and the material of the first transparent conductor layer 29 (FIG. 2) scattered from the first target material 15 is attached to the first surface of the film base 13. In this way, the first transparent conductor layer 29 (FIG. 2) is formed on the first surface of the film substrate 13.

  Subsequently, a first metal layer 30 (FIG. 2) is formed on the first transparent conductor layer 29 (FIG. 2). The first film forming roll 14 is rotated to continuously move the film base 13 on which the first transparent conductor layer 29 (FIG. 2) has been formed to the film forming position of the first metal layer 30. When the first metal layer 30 is formed by sputtering, a DC voltage is applied between the first film forming roll 14 and the second target material 16 to generate, for example, argon plasma. The DC voltage is, for example, 0V for the first film forming roll 14 and −400V to −100V for the second target material 16. Argon ions collide with the second target material 16 and the material of the first metal layer 30 (FIG. 2) scattered from the second target material 16 is used as the first transparent conductor layer 29 (FIG. 2) on the film substrate 13. Adhere to the surface. A first metal layer 30 (FIG. 2) is formed on the surface of the first transparent conductor layer 29 (FIG. 2) on the film substrate 13.

  Subsequently, the surface of the first metal layer 30 (FIG. 2) is oxidized to obtain a metal oxide film layer 31 (FIG. 2). Oxygen gas is supplied to the oxygen atmosphere chamber 17, and the pressure of the oxygen gas is preferably 0.0005 Pa to 1 Pa, more preferably 0.0005 Pa to 0.1 Pa. In the oxygen atmosphere chamber 17, substantially only oxygen gas exists. While the film base material 13 on which the first metal layer 30 (FIG. 2) is formed is wound around the first film formation roll 14, the first film formation roll 14 is rotated and continuously moved to the oxygen atmosphere chamber 17. . The surface of the first metal layer 30 (FIG. 2) is oxidized in an oxygen atmosphere to form a metal oxide film layer 31 (FIG. 2).

  Subsequently, a second transparent conductor layer 32 (FIG. 2) is formed on the second surface of the film base 13. Before the film formation of the second transparent conductor layer 32 (FIG. 2), the film base 13 is not once wound into a roll. The film substrate 13 on which the metal oxide film layer 31 (FIG. 2) is formed is transported through the sputtering apparatus 10 and is transported to the film forming process of the second transparent conductor layer 32 (FIG. 2).

  The film base 13 is wound around the second film forming roll 21 and the second film forming roll 21 is rotated to continuously move the film base 13 to the film forming position of the second transparent conductor layer 32 (FIG. 2). Let At this time, the film substrate 13 is wound around the second film-forming roll 21 with the second surface facing outward. When the second transparent conductor layer 32 (FIG. 2) is formed by sputtering, a DC voltage is applied between the second film forming roll 21 and the third target material 22 to generate, for example, argon plasma. The DC voltage is, for example, 0V for the second film forming roll 21 and −400V to −100V for the third target material 22. Argon ions are collided with the third target material 22, and the material of the second transparent conductor layer 32 (FIG. 2) scattered from the third target material 22 is attached to the second surface of the film base 13. In this way, the second transparent conductor layer 32 (FIG. 2) is formed on the second surface of the film substrate 13.

  Subsequently, a second metal layer 33 (FIG. 2) is formed on the second transparent conductor layer 32 (FIG. 2). The 2nd film-forming roll 21 is rotated and the film base material 13 is continuously moved to the film-forming position of the 2nd metal layer 33 (FIG. 2). When the second metal layer 33 is formed by sputtering, a DC voltage is applied between the second film forming roll 21 and the fourth target material 23 to generate, for example, argon plasma. The DC voltage is, for example, 0V for the second film forming roll 21 and −400V to −100V for the fourth target material 23. Argon ions are caused to collide with the fourth target material 23, and the material of the second metal layer 33 (FIG. 2) scattered from the fourth target material 23 is attached to the surface of the second transparent conductor layer 32 (FIG. 2). In this way, the second metal layer 33 (FIG. 2) is formed on the surface of the second transparent conductor layer 32 (FIG. 2).

  The film base 13 (conductive film 35 (FIG. 2)) on which the film formation on the first surface and the second surface has been completed is wound into a roll to obtain the second roll 25. The second roll 25 is a completed product of the conductive film roll 34 (FIG. 2).

  After the second metal layer 33 (FIG. 2) is formed, the surface of the second metal layer 33 (FIG. 2) is oxidized before being wound around the second roll 25, and the second metal oxide film layer (illustrated) is shown. Not).

[Conductive film roll]
A conductive film 35 obtained by the manufacturing method of the present invention has the following configuration shown in FIG.
(a) Film substrate 13
(b) The first transparent conductor layer 29 laminated on the first surface of the film substrate 13
(c) The first metal layer 30 laminated on the first transparent conductor layer 29
(d) Metal oxide film layer 31 formed on the surface of the first metal layer 30
(e) The second transparent conductor layer 32 laminated on the second surface of the film substrate 13
(f) Second metal layer 33 laminated on second transparent conductor layer 32

  The conductive film roll 34 is obtained by winding a long conductive film 35 into a roll shape. The length of the conductive film 35 is typically 100 m or more, and preferably 500 m to 5000 m. In order to wind the conductive film 35 around the center of the conductive film roll 34, a plastic or metal core 36 is usually arranged.

[Film substrate]
The thickness of the film base 13 is, for example, 20 μm to 200 μm. The material of the film base 13 is desirably a material excellent in transparency and heat resistance. The material of the film substrate 13 is preferably polyethylene terephthalate, polycycloolefin, or polycarbonate.

  The film base 13 may be provided with an easy-adhesion layer (not shown) for improving the adhesion between the film base 13 and the first transparent conductor layer 29 on the first surface. Moreover, the film base material 13 may be equipped with the easily bonding layer (not shown) for improving the adhesiveness of the film base material 13 and the 2nd transparent conductor layer 32 on the 2nd surface.

  The film base 13 may include a refractive index adjustment layer (index-matching layer; not shown) for adjusting the reflectance of the film base 13 on the first surface. Moreover, the film base material 13 may be provided with a refractive index adjustment layer (index-matching layer; not shown) for adjusting the reflectance of the film base material 13 on the second surface.

  The film substrate 13 may include a hard coat layer (not shown) for preventing the first surface from being damaged. Further, the film base 13 may include a hard coat layer (not shown) for preventing the second surface from being damaged.

[Transparent conductor layer]
The first transparent conductor layer 29 desirably has a high transmittance in the visible light region (400 nm to 700 nm) and a low surface resistance value per unit area. The transmittance of the first transparent conductor layer 29 in the visible light region is preferably 80% or more. The surface resistance value per unit area of the first transparent conductor layer 29 is preferably 500 Ω / □ (ohms per square) or less. The material forming the first transparent conductor layer 29 is preferably indium tin oxide (ITO), indium zinc oxide, or indium oxide-zinc oxide composite oxide. The thickness of the first transparent conductor layer 29 is preferably 20 nm to 80 nm. The transmittance, surface resistance value, material, and thickness of the second transparent conductor layer 32 are the same as those of the first transparent conductor layer 29.

[Metal layer]
The first metal layer 30 is formed on the surface of the first transparent conductor layer 29. The material of the first metal layer 30 is preferably copper, silver, aluminum, nickel alloy, copper alloy, titanium alloy, or silver alloy, and more preferably copper. The surface resistance value per unit area of the first metal layer 30 is preferably 10Ω / □ (ohms per square) or less, and more preferably 0.1Ω / □ to 1Ω / □. The thickness of the first metal layer 30 is preferably 20 nm to 300 nm. If the thickness of the first metal layer 30 is less than 20 nm, the first metal layer 30 may not be a complete film. If the thickness of the first metal layer 30 is less than 20 nm, even if the first metal layer 30 is a complete film, the electrical resistance may be excessively increased. If the thickness of the first metal layer 30 exceeds 300 nm, the workability of the wiring may be deteriorated (fine pattern formation becomes difficult). The material, surface resistance value, and thickness of the second metal layer 33 are the same as those of the first metal layer 30.

[Metal oxide film layer]
The metal oxide film layer 31 is obtained by oxidizing the surface of the first metal layer 30. The metal oxide film layer 31 is preferably copper oxide, silver oxide, aluminum oxide, nickel alloy oxide, copper alloy oxide, titanium alloy oxide, silver alloy oxide, and more preferably copper oxide. is there. The thickness of the metal oxide film layer 31 is preferably 1 nm to 15 nm. If the thickness of the metal oxide film layer 31 is less than 1 nm, the metal oxide film layer 31 may not be able to completely cover the surface of the first metal layer 30. In this case, there is a possibility that the effect of preventing pressure bonding cannot be obtained sufficiently. When the thickness of the metal oxide film layer 31 exceeds 15 nm, the oxidation time of the first metal layer 30 becomes long, and the productivity may be reduced.

  The conductive film 35 used in the present invention may further have a second metal oxide film layer (not shown) on the surface of the second metal layer 33. The second metal oxide film layer is obtained by oxidizing the surface of the second metal layer 33. The material and thickness of the second metal oxide film layer are the same as those of the metal oxide film layer 31.

[Example]
A first roll 12 formed by winding a film substrate 13 was set in the sputtering apparatus 10 of FIG. The film substrate 13 was a polycycloolefin film (“ZEONOR” (registered trademark) manufactured by Nippon Zeon Co., Ltd.) having a thickness of 100 μm and a length of 1000 m. The atmosphere of the chamber 11 of the sputtering apparatus 10 was changed to an argon gas atmosphere having a pressure of 0.4 Pa. As the 1st target material 15 and the 3rd target material 22, the sintered compact target material containing an indium oxide and a tin oxide was used. Oxygen-free copper target material was used as the second target material 16 and the fourth target material 23.

  The film base material 13 is wound around the first film forming roll 14 with the first surface facing outward while the first roll 12 is rewound, and the film base material 13 is continuously moved by rotating the first film forming roll 14. It was. A first transparent conductor layer 29 and a first metal layer 30 were continuously formed on the first surface of the film substrate 13. The first transparent conductor layer 29 was an indium tin oxide layer (ITO layer) having a thickness of 20 nm. The first metal layer 30 was a copper layer having a thickness of 50 nm.

  Oxygen gas was supplied to the oxygen atmosphere chamber 17 from the oxygen gas introduction pipe, and the oxygen gas partial pressure in the oxygen atmosphere chamber 17 was set to 0.001 Pa. The surface of the first metal layer 30 (copper layer) was oxidized in this oxygen atmosphere to form a metal oxide film layer 31 (copper oxide layer, thickness 2 nm).

  The film base 13 on which the film formation was completed on the first surface was conveyed through the sputtering apparatus 10 and supplied to the second film formation roll 21. The film base 13 was wound around the second film-forming roll 21 with the second surface outside, and the film base 13 was continuously moved by rotating the second film-forming roll 21. A second transparent conductor layer 32 and a second metal layer 33 were continuously formed on the second surface of the film substrate 13. The second transparent conductor layer 32 was an indium tin oxide layer (ITO layer) having a thickness of 20 nm. The second metal layer 33 was a copper layer having a thickness of 50 nm. Thus, the film base material 13 (conductive film 35) in which all film formation was completed was obtained.

  The film base material 13 (conductive film 35) for which all film formation was completed was wound around a plastic core 36 to form a roll, and a conductive film roll 34 was produced.

  (Press-bonding test) The conductive film roll 34 of the example was rewound and the surface of the conductive film 35 was observed. In the electroconductive film roll 34 of an Example, the peeling sound of the crimping | compression-bonding part did not generate | occur | produce in the case of rewinding. Moreover, the damage | wound which generate | occur | produces at the time of peeling of a crimping | compression-bonding part was not recognized on the surface of the conductive film 35 which rewinded. Therefore, in the conductive film roll 34 of an Example, it is estimated that the crimping | compression-bonding did not generate | occur | produce.

[Comparative example]
A conductive film roll was produced in the same manner as in the example except that the oxidation process on the surface of the first metal layer 30 was not performed. (Specifically, oxygen gas was not supplied to the oxygen atmosphere chamber 17.) In the conductive film roll of the comparative example, a peeling sound was generated that broke the pressure bonding during rewinding. In addition, many scratches due to the pressure bonding were observed on the surface of the conductive film. Therefore, it is presumed that crimping occurred in the conductive film roll of the comparative example.

[Measuring method]
[Thickness of metal oxide layer]
The thickness of the metal oxide film layer was measured using an X-ray photoelectron spectroscopy analyzer (“Quantera SXM” manufactured by PHI).
[Thickness of transparent conductor layer, thickness of metal layer, thickness of film substrate]
The thickness of the transparent conductor layer and the thickness of the metal layer were measured by performing cross-sectional observation with a transmission electron microscope (“H-7650” manufactured by Hitachi, Ltd.). The thickness of the film substrate was measured using a film thickness meter (Digital Dial Gauge DG-205 manufactured by Peacock).
[Press bonding of conductive film roll]
The conductive film 35 was rewound from the conductive film roll 34, and the surface of the conductive film 35 was observed to confirm the presence or absence of pressure bonding. When crimping occurs, a peeling sound that breaks the crimping occurs during rewinding. In addition, a large number of scratches resulting from the pressure bonding are generated on the surface of the conductive film 35.

  There is no restriction | limiting in the use of the electroconductive film 35 obtained by the manufacturing method of this invention. The conductive film 35 obtained by the production method of the present invention is cut into a display panel size and is suitably used for a touch panel, particularly a capacitive touch panel.

DESCRIPTION OF SYMBOLS 10 Sputtering device 11 Chamber 12 First roll 13 Film substrate 14 First film forming roll 15 First target material 16 Second target material 17 Oxygen atmosphere chamber 18 Oxygen cylinder 19 Adjustment valve 20 Oxygen gas introduction pipe 21 Second film forming roll 22 Third target material 23 Fourth target material 24 Guide roll 25 Second roll 26 Partition plate 29 First transparent conductor layer 30 First metal layer 31 Metal oxide film layer 32 Second transparent conductor layer 33 Second metal layer 34 Conductive film roll 35 Conductive film 36 Core

Claims (5)

A film substrate;
A first transparent conductor layer laminated on the first surface of the film substrate;
A first metal layer laminated on the first transparent conductor layer;
A metal oxide film layer formed on the surface of the first metal layer;
A second transparent conductor layer laminated on the second surface of the film substrate;
A conductive film comprising a second metal layer laminated on the second transparent conductor layer ,
The first metal layer is made of copper;
The metal oxide film layer formed on the surface of the first metal layer comprises a copper oxide layer,
The electroconductive film whose surface resistance value per unit area of any one or both of said 1st metal layer and said 2nd metal layer is 10 ohms / square (ohms per square) or less . A film substrate;
A first transparent conductor layer laminated on the first surface of the film substrate;
A first metal layer laminated on the first transparent conductor layer;
A metal oxide film layer formed on the surface of the first metal layer;
A second transparent conductor layer laminated on the second surface of the film substrate;
A conductive film comprising a second metal layer laminated on the second transparent conductor layer,
The first metal layer is silver, copper, aluminum, copper alloy, silver alloy,
Wherein the first metal layer the metal oxide layer formed on the surface of, Ri Do oxide film of the first metal layer,
The electroconductive film whose surface resistance value per unit area of any one or both of said 1st metal layer and said 2nd metal layer is 10 ohms / square (ohms per square) or less.   The conductive film according to claim 1, further comprising a second metal oxide film layer on a surface of the second metal layer.   The conductive film according to claim 1, wherein the metal oxide film layer formed on the surface of the second metal layer is formed of an oxide film of the second metal layer. The electroconductive film roll formed by winding the electroconductive film in any one of Claims 1-4 in roll shape.

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