Light-transmitting conductive sheet, contact sensor, light-adjusting element, photoelectric conversion element, heat ray control member, antenna, electromagnetic wave shielding member, and image display device

Abstract

The transparent conductive sheet 1 has a substrate sheet 2 and a transparent conductive layer 3 sequentially arranged on its thickness-direction side. The transparent conductive layer 3, on its thickness-direction side, includes a first region 6 and a second region 7. The first region 6 is predominantly amorphous. The second region 7 is crystalline. The second region 7 is thicker than the region of the first region 6. The thickness of the transparent conductive layer 3 exceeds 30 nm.

Description

Technical Field

[0001] This invention relates to a light-transmitting conductive sheet, a contact sensor, a dimming element, a photoelectric conversion element, a hot wire control component, an antenna, an electromagnetic wave shielding component, and an image display device. Background Technology

[0002] Previously, transparent conductive films having a substrate film and a transparent conductive film formed from ITO were known.

[0003] For example, a transparent conductive film comprising an amorphous ITO film and a crystalline ITO film disposed thereon has been proposed (see, for example, Patent Document 1 below). In the transparent conductive film described in Patent Document 1, the amorphous ITO film (lower layer) is thicker than the crystalline ITO film (upper layer). As a result, the transparent conductive film described in Patent Document 1 exhibits both improved etchability and excellent durability.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 8-174746 Summary of the Invention

[0007] The problem the invention aims to solve

[0008] However, low resistivity is required for transparent conductive films. However, the transparent conductive film described in Patent Document 1 has drawbacks that fail to meet these requirements.

[0009] Furthermore, crack suppression is required for transparent conductive films.

[0010] The present invention provides a transparent conductive sheet having a transparent conductive layer that has both low resistivity and suppresses cracking, and includes a contact sensor, a dimming element, a photoelectric conversion element, a hot wire control component, an antenna, an electromagnetic wave shielding component, and an image display device thereof.

[0011] Solution for solving the problem

[0012] The present invention (1) includes a light-transmitting conductive sheet, which has a resin layer and a light-transmitting conductive layer sequentially on one side facing the thickness direction. The light-transmitting conductive layer includes a first region and a second region sequentially on the side facing the thickness direction. The main region of the first region is amorphous, the second region is crystalline, the second region is thicker than the first region, and the thickness of the light-transmitting conductive layer exceeds 30 nm.

[0013] The present invention (2) includes the light-transmitting conductive sheet described in (1), wherein the thickness of the aforementioned second region is in a ratio of 0.73 or more to the thickness of the aforementioned light-transmitting conductive layer.

[0014] The present invention (3) includes the light-transmitting conductive sheet described in (1) or (2), wherein the material of the aforementioned light-transmitting conductive layer is a composite oxide containing indium and tin.

[0015] The present invention (4) includes a contact sensor having a light-transmitting conductive sheet as described in any one of (1) to (3).

[0016] The present invention (5) includes a dimming element comprising a light-transmitting conductive sheet as described in any one of (1) to (3).

[0017] The present invention (6) includes a photoelectric conversion element comprising a light-transmitting conductive sheet as described in any one of (1) to (3).

[0018] The present invention (7) includes a hot wire control component having a light-transmitting conductive sheet as described in any one of (1) to (3).

[0019] The present invention (8) includes an antenna having a light-transmitting conductive sheet as described in any one of (1) to (3).

[0020] The present invention (9) includes an electromagnetic wave shielding member having a light-transmitting conductive sheet as described in any one of (1) to (3).

[0021] The present invention (10) includes an image display device comprising a light-transmitting conductive sheet as described in any one of (1) to (3).

[0022] The effects of the invention

[0023] The transparent conductive layer of the transparent conductive sheet of the present invention has both low resistivity and suppresses cracking.

[0024] The contact sensor, dimming element, photoelectric conversion element, hot wire control component, antenna, electromagnetic wave shielding component, and image display device of the present invention have the above-mentioned light-transmitting conductive sheet, and therefore have excellent reliability. Attached Figure Description

[0025] Figure 1 This is a cross-sectional view of one embodiment of the light-transmitting conductive sheet of the present invention.

[0026] Figure 2 This is a schematic diagram of the sputtering device.

[0027] Figure 3 yes Figure 1 A cross-sectional view of a modified example of the transparent conductive sheet shown.

[0028] Figure 4 This is an image processing diagram of the TEM photograph from Example 2.

[0029] Figure 5This is an image processing diagram of the TEM photograph from Example 3. Detailed Implementation

[0030] (An embodiment of a light-transmitting conductive sheet)

[0031] Reference Figure 1 This describes one embodiment of the light-transmitting conductive sheet of the present invention.

[0032] The light-transmitting conductive sheet 1 is a component found in contact sensors, dimming elements, photoelectric conversion elements, hot-wire control components, antennas, electromagnetic wave shielding components, and image display devices, which are described later. The light-transmitting conductive sheet 1 is an intermediate component used in the manufacture of these devices. The light-transmitting conductive sheet 1 is a device that can be independently manufactured and used industrially.

[0033] The light-transmitting conductive sheet 1 has a thickness and a flat plate shape extending in a surface direction orthogonal to the thickness direction. The light-transmitting conductive sheet 1 has a substrate sheet 2, which is an example of a resin layer, and a light-transmitting conductive layer 3 sequentially disposed on one surface of the substrate sheet 2 in the thickness direction. Preferably, the light-transmitting conductive sheet 1 only has a substrate sheet 2 and a light-transmitting conductive layer 3.

[0034] (Substrate sheet)

[0035] The substrate sheet 2 has a thickness and a flat plate shape extending in the surface direction. The substrate sheet 2 forms the other side of the light-transmitting conductive sheet 1 in the thickness direction. The substrate sheet 2 has a thin film shape extending in the surface direction. The substrate sheet 2 is flexible. The substrate sheet 2 includes at least a substrate layer 4. Specifically, the substrate sheet 2 has a substrate layer 4 and a hard coating layer 5 sequentially disposed on the side facing the thickness direction. It should be noted that, in this embodiment, the number of substrate sheets 2 included in the light-transmitting conductive sheet 1 is one.

[0036] The substrate layer 4 has a thin film shape extending in the planar direction. The substrate layer 4 forms the other side of the substrate sheet 2 in the thickness direction. The material of the substrate layer 4 is not particularly limited, and examples include polymers, glass, etc. Polymers are preferred. Examples of polymers include olefin resins such as polyethylene, polypropylene, and cyclic olefin polymers (COP); polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate; (meth)acrylic resins (acrylic resins and / or methacrylic resins) such as polymethacrylate; and resins such as polycarbonate resin, polyethersulfone resin, polyarylate resin, melamine resin, polyamide resin, polyimide resin, cellulose resin, and polystyrene resin. Polyester resins are preferred, and PET is more preferred. The thickness of the substrate layer 4 is, for example, 10 μm or more, preferably 30 μm or more, and also, for example, 300 μm or less, preferably 200 μm or less, more preferably 100 μm or less, and even more preferably 75 μm or less.

[0037] The hard coating layer 5 is a scratch-resistant layer used to prevent scratches on the transparent conductive layer 3. The hard coating layer 5 forms on one surface of the substrate sheet 2 in the thickness direction. The hard coating layer 5 is in complete contact with one surface of the substrate layer 4 in the thickness direction. Examples of hard coating layers 5 include cured products of hard coating compositions (acrylic resins, urethane resins, etc.) disclosed in Japanese Patent Application Publication No. 2016-179686. The thickness of the hard coating layer 5 is, for example, 0.1 μm or more, preferably 0.5 μm or more, and also, for example, 10 μm or less, preferably 5 μm or less.

[0038] (Substrate properties)

[0039] The thickness of the substrate sheet 2 is, for example, 1 μm or more, preferably 10 μm or more, more preferably 15 μm or more, and even more preferably 30 μm or more. In addition, it is, for example, 310 μm or less, preferably 210 μm or less, more preferably 110 μm or less, and even more preferably 80 μm or less.

[0040] The total light transmittance of the substrate sheet 2 (JIS K 7375-2008) is, for example, 60% or more, preferably 80% or more, more preferably 85% or more, and, for example, 100% or less.

[0041] (Transparent conductive layer)

[0042] A light-transmitting conductive layer 3 forms one surface of the light-transmitting conductive sheet 1 in the thickness direction. The light-transmitting conductive layer 3 is supported by the substrate sheet 2 from the other side in the thickness direction. The light-transmitting conductive layer 3 is in complete contact with one surface of the substrate sheet 2 in the thickness direction. In other words, the light-transmitting conductive layer 3 is in contact with one surface of the substrate sheet 2 in the thickness direction. The light-transmitting conductive layer 3 has a first region 6 and a second region 7 on its thickness-direction side. Therefore, the substrate sheet 2, the first region 6, and the second region 7 are sequentially arranged on the thickness-direction side of the light-transmitting conductive sheet 1. It should be noted that in this embodiment, the number of light-transmitting conductive layers 3 in the light-transmitting conductive sheet 1 is one.

[0043] (Region 1)

[0044] In this embodiment, the first region 6 is the portion of the transparent conductive layer 3 on the other side in the thickness direction. The first region 6 includes the other side of the transparent conductive layer 3 in the thickness direction.

[0045] The first region 6 includes areas exhibiting amorphous (non-crystalline) properties upon cross-section. Amorphous properties in the first region 6 can manifest in several ways: for example, the entire region of the first region 6 is amorphous upon cross-section; or, for example, the main region of the first region 6 is amorphous upon cross-section, with a small remaining crystalline region. The amorphous properties in the first region 6 are confirmed by observation of a cross-sectional TEM image. Specifically, for example... Figure 4 As shown, the black area was identified as the amorphous first region 6 through cross-sectional TEM images. Furthermore, as described later, by observing the presence or absence of lattice stripes and confirming the proportion of areas with lattice stripes using high-magnification cross-sectional TEM, it is also possible to identify the first region 6 as amorphous and / or predominantly amorphous region. It should be noted that, during cross-section viewing, the area ratio (area ratio of amorphous material) of the predominant region in the first region 6 is, for example, 0.6 or more, preferably 0.8 or more, more preferably 0.9 or more, and, for example, 1 or less.

[0046] The thickness of the first region 6 is the thickness of the aforementioned main region, and is set in a desired range as a ratio of its thickness to the thickness of the second region 7 described later. The thickness of the first region 6 is, for example, 30 nm or less, preferably 25 nm or less, more preferably 20 nm or less, and even more preferably 15 nm or less. In addition, it is, for example, 1 nm or more, preferably 5 nm or more, and more preferably 10 nm or more.

[0047] The method for measuring the thickness of the first region 6 is described in the examples.

[0048] (Second Zone)

[0049] In this embodiment, the second region 7 is one side portion of the light-transmitting conductive layer 3 along its thickness direction. The second region 7 includes one side of the light-transmitting conductive layer 3 along its thickness direction. Furthermore, the second region 7 is continuous with one side portion of the first region 6 along its thickness direction.

[0050] The second region 7, when viewed in section, includes a region that exhibits crystalline properties as its main region, specifically, crystalline (crystallinity).

[0051] The second region 7 may contain a small amount of amorphous material. Specifically, the area ratio (area ratio of crystalline material) of the main regions in the second region 7 is, for example, 0.7 or more, preferably 0.8 or more, more preferably 0.9 or more, and, for example, 1 or less.

[0052] The crystallinity in region 7 was confirmed by observation of cross-sectional TEM images. Specifically, for example... Figure 4 As shown, the gray area was identified as the second region 7 of crystalline material through cross-sectional TEM images. Furthermore, as described later, by observing the presence or absence of lattice stripes and confirming the proportion of areas with lattice stripes using high-magnification cross-sectional TEM, it is also possible to identify the second region 7 as crystalline material and / or as a predominantly crystalline region.

[0053] The second region 7 is thicker than the first region 6 (the main region in the first region 6). On the other hand, if the second region 7 is thinner than the first region 6 or has the same thickness, the resistivity increases.

[0054] Specifically, the ratio of the thickness of the second region 7 to the thickness of the first region 6 is greater than 1.0, preferably 1.3 or more, more preferably 2 or more, and even more preferably 4 or more. Furthermore, the ratio of the thickness of the second region 7 to the thickness of the light-transmitting conductive layer 3 is greater than 0.50, preferably 0.56 or more, more preferably 0.70 or more, even more preferably 0.73 or more, and particularly preferably 0.80 or more. If the ratio of the thickness of the second region 7 to the thickness of the first region 6 and / or the ratio of the thickness of the second region 7 to the thickness of the light-transmitting conductive layer 3 is at or above the aforementioned lower limit, a low resistivity of the light-transmitting conductive layer 3 can be ensured.

[0055] Furthermore, the ratio of the thickness of the second region 7 to the thickness of the first region 6 is preferably 1000 or less, more preferably 100 or less, more preferably 50 or less, even more preferably 20 or less, particularly preferably 15 or less, and especially preferably 10 or less. Additionally, the ratio of the thickness of the second region 7 to the thickness of the light-transmitting conductive layer 3 is preferably less than 1.00, preferably 0.99 or less, more preferably 0.95 or less, and even more preferably 0.90 or less. If the ratio of the thickness of the second region 7 to the thickness of the first region 6 and / or the ratio of the thickness of the second region 7 to the thickness of the light-transmitting conductive layer 3 is below the aforementioned upper limit, the amount of crack formation in the light-transmitting conductive layer 3 can be suppressed.

[0056] Furthermore, the thickness of the second region 7 is set such that the thickness ratio of the second region 7 falls within the aforementioned range. Specifically, for example, it is greater than 25 nm, preferably 30 nm or more, more preferably 50 nm or less, further preferably 65 nm or more, and especially preferably 100 nm or more. Additionally, the thickness of the second region 7 is, for example, less than 500 nm, preferably 300 nm or less, and more preferably 200 nm or less.

[0057] The method for measuring the thickness of the second region 7 is described in the examples.

[0058] (Materials for the transparent conductive layer)

[0059] Examples of materials that can be used as the transparent conductive layer 3 include conductive oxides. Examples of conductive oxides include metal oxides comprising at least one metal or half-metal selected from the group consisting of In, Sn, Zn, Ga, Sb, Ti, Si, Zr, Mg, Al, Au, Ag, Cu, Pd, and W. The metal oxide may be further doped with metal atoms or half-metal atoms shown in the above group, as needed.

[0060] Specifically, conductive oxides include indium zinc oxide (IZO), indium gallium zinc oxide (IGZO), indium gallium oxide (IGO), indium tin oxide (ITO), and antimony tin oxide (ATO). From the viewpoint of improving transparency and conductivity, indium tin oxide (ITO), which contains both indium and tin, is preferred. If the conductive oxide is ITO, its transparency and conductivity are even better.

[0061] The concentrations of indium oxide and tin oxide in ITO are appropriately set according to the application and purpose. Specifically, the concentration of tin oxide in the conductive oxide is, for example, 0.1% by mass or more, preferably 1% by mass or more, and for example, 30% by mass or less.

[0062] (Properties of the transparent conductive layer)

[0063] The thickness of the transparent conductive layer 3 exceeds 30 nm. If the thickness of the transparent conductive layer 3 is less than 30 nm, the resistivity of the transparent conductive layer 3 increases. Furthermore, the thickness of the transparent conductive layer 3 is preferably 40 nm or more, more preferably more than 50 nm, further preferably 60 nm or more, particularly preferably 75 nm or more, especially preferably 100 nm or more, and most preferably 125 nm or more. It is also, for example, 500 nm or less, preferably 300 nm or less, more preferably 250 nm or less, further preferably 200 nm or less, and particularly preferably 175 nm or less. If the thickness of the transparent conductive layer 3 is above or below the aforementioned lower limit, the resistivity can be reduced. If the thickness of the transparent conductive layer 3 is below or below the aforementioned upper limit, cracking can be suppressed.

[0064] The total light transmittance of the light-transmitting conductive layer 3 (JIS K 7375-2008) is, for example, 60% or more, preferably 80% or more, more preferably 85% or more, and, for example, 100% or less.

[0065] The surface resistance of the light-transmitting conductive layer 3 is, for example, 200 Ω / □ or less, preferably 65 Ω / □ or less, more preferably 45 Ω / □ or less, even more preferably 30 Ω / □ or less, particularly preferably 20 Ω / □ or less, and, for example, more than 0 Ω / □. The surface resistance is measured according to JIS K7194 using the four-terminal method.

[0066] The resistivity of the transparent conductive layer 3 is, for example, 7.0 × 10⁻⁶. -4 Below Ωcm, preferably 2.8×10 -4 Ωcm or less, more preferably 2.5×10 -4 Below Ωcm, further preferably 2.2×10 -4 Below Ωcm, and more preferably 0.1 × 10 Ωcm, for example, above 0 Ωcm. -4 Ωcm or more, more preferably 0.5×10 -4 Ωcm or more, and more preferably 1.0×10 -4 Above Ωcm. Resistivity is obtained by multiplying the surface resistance by the thickness.

[0067] (Physical properties of transparent conductive sheets)

[0068] The thickness of the light-transmitting conductive sheet 1 is, for example, 1 μm or more, preferably 10 μm or more, more preferably 15 μm or more, and even more preferably 30 μm or more. In addition, it is, for example, 310 μm or less, preferably 210 μm or less, more preferably 120 μm or less, and even more preferably 90 μm or less.

[0069] The total light transmittance (JIS K 7375-2008) of the light-transmitting conductive sheet 1 is, for example, 60% or more, preferably 80% or more, more preferably 85% or more, and, for example, 100% or less.

[0070] (Manufacturing method of transparent conductive sheet 1)

[0071] Next, refer to Figure 2 The manufacturing method of the light-transmitting conductive sheet 1 will be described below. In this method, a light-transmitting conductive layer 3 is formed on a substrate sheet 2 using, for example, a roll-to-roll method.

[0072] In this method, a substrate sheet 2 is first prepared. Specifically, a hard coating composition is applied to one side of the substrate layer 4 in the thickness direction and dried, allowing the hard coating composition to cure. Thus, a substrate sheet 2 is prepared. Figure 1 As shown, a substrate sheet 2 has a substrate layer 4 and a hard coating layer 5 sequentially on one side along the thickness direction.

[0073] Next, a transparent conductive layer 3 is formed by sputtering. Specifically, the transparent conductive layer 3 is formed while the substrate sheet 2 is transported using the sputtering apparatus 30.

[0074] [Sputtering device]

[0075] like Figure 2 As shown, the sputtering apparatus 30 sequentially includes an extraction section 35, a sputtering section 36, and a take-up section 37.

[0076] The extraction section 35 is equipped with an extraction roller 38.

[0077] The sputtering section 36 includes a film-forming roller 40, a first film-forming chamber 41, and a second film-forming chamber 42.

[0078] The film forming roller 40 is equipped with a cooling device (not shown) configured to cool the film forming roller 40.

[0079] The first film-forming chamber 41 houses the outlets of the first target 51, the first gas supply unit 61, and the first pump 71. The outlets of the first target 51, the first gas supply unit 61, and the first pump 71 are arranged at intervals relative to the film-forming roller 40. In the first film-forming chamber 41, a magnet (not shown) is arranged on the opposite side of the film-forming roller 40 relative to the first target 51. The magnetic field strength of the magnet is adjusted such that the horizontal magnetic field strength on the first target 51 is, for example, 10 mT or more and 200 mT or less.

[0080] Materials similar to the conductive oxides described above can be used as the material for the first target 51. It should be noted that the material of the first target 51 comprises a sintered body of a conductive oxide. The first target 51 is configured such that an electric current can be applied at a predetermined electric current density.

[0081] The first gas supply unit 61 is configured to supply sputtering gas into the first film-forming chamber 41. Examples of sputtering gases include inert gases such as nitrogen and argon; and mixtures of inert gases and reactive gases such as oxygen, with mixtures being preferred. If the sputtering gas is a mixture, the first gas supply unit 61 includes a first inert gas supply unit 63 and a first reactive gas supply unit 64, which supply the inert gas and the reactive gas, respectively, into the first film-forming chamber 41.

[0082] The second film-forming chamber 42 is disposed adjacent to the first film-forming chamber 41 in the circumferential direction of the film-forming roller 40. The second film-forming chamber 42 houses the outlets of the second target 52, the second gas supply unit 62, and the second pump 72. The outlets of the second target 52, the second gas supply unit 62, and the second pump 72 are arranged at intervals relative to the film-forming roller 40. In the second film-forming chamber 42, a magnet (not shown) is disposed on the opposite side of the film-forming roller 40 relative to the second target 52. The magnetic field strength of the magnet is adjusted such that the horizontal magnetic field strength on the second target 52 is, for example, 10 mT or more and 200 mT or less.

[0083] Materials similar to the conductive oxides described above can be used as the material for the second target 52. It should be noted that the material of the second target 52 comprises a sintered body of the conductive oxide. The second target 52 is configured such that an electric current can be applied at a specified electric current density.

[0084] The second gas supply unit 62 is configured to supply a second sputtering gas into the second film-forming chamber 42. Examples of the second sputtering gas include, for example, an inactive gas and a mixed gas, with a mixed gas being preferred. If the second sputtering gas is a second mixed gas, the second gas supply unit 62 includes a second inactive gas supply unit 65 and a second reactive gas supply unit 66, which supply the inactive gas and the reactive gas, respectively, into the second film-forming chamber 42.

[0085] The winding section 37 is equipped with a winding roller 39.

[0086] [Manufacturing method of light-transmitting conductive sheet 1]

[0087] In order to form a transparent conductive layer 3 on the substrate sheet 2 using the sputtering device 30, the substrate sheet 2 is first placed on the extraction roller 38, the film forming roller 40 and the winding roller 39.

[0088] While driving the first pump 71, sputtering gas is supplied from the first gas supply unit 61 to the first film-forming chamber 41. If the sputtering gas is a mixed gas, the ratio R1 of the reactive gas to the inactive gas in the mixed gas, based on a capacity basis, is, for example, 0.001 or more, preferably 0.005 or more, and also, for example, 0.2 or less, preferably 0.1 or less.

[0089] The pressure in the first film-forming chamber 41 is, for example, less than 1 Pa.

[0090] While driving the second pump 72, sputtering gas is supplied from the second gas supply unit 62 to the second film-forming chamber 42. If the sputtering gas is a mixed gas, the ratio R2 of the reactive gas to the inactive gas in the mixed gas, based on a capacity basis, is, for example, 0.001 or more, preferably 0.005 or more, and also, for example, 0.2 or less, preferably 0.1 or less.

[0091] Furthermore, the ratio of R1 to R2 (R1 / R2) is, for example, 2 or less, preferably less than 1, more preferably 0.9 or less, further preferably 0.8 or less, especially preferably 0.7 or less, and for example, 0.01 or more, preferably 0.1 or more, more preferably 0.5 or more. The pressure in the second film-forming chamber 42 is, for example, 1 Pa or less.

[0092] Additionally, a driving cooling device is used to cool the surface of the film-forming roller 40. The temperature (surface temperature) of the film-forming roller 40 is, for example, 20°C or less, preferably 10°C or less, more preferably 0.0°C or less, and also, for example, -50°C or more, preferably -25°C or more.

[0093] Electricity is applied to the first target 51 and the second target 52 respectively. Specifically, electricity is applied to the first target 51 with an electric current density P1, and electricity is applied to the second target 52 with an electric current density P2.

[0094] It should be noted that there are no particular limitations on the power supply applied to the first target 51 and the second target 52, and examples include DC and RF. The power supply is preferably DC.

[0095] The ratio (P1 / P2) of the electric power density P1 of the first target 51 to the electric power density P2 of the second target 52 is, for example, 0.45 or less, preferably 0.40 or less, more preferably 0.32 or less, and even more preferably 0.30 or less. It is also, for example, 0.05 or more, preferably 0.10 or more, more preferably 0.16 or more, and even more preferably 0.20 or more. If the ratio (P1 / P2) of the electric power density P1 of the first target 51 is below the aforementioned upper limit, a second amorphous conductive film 82 (described later) that is thicker than the first amorphous conductive film 81 (described later) can be reliably formed. If the ratio (P1 / P2) of the electric power density P1 of the first target 51 is above the aforementioned lower limit, a first amorphous conductive film 81 that maintains amorphous properties in the first region 6 during subsequent crystallization processes can be easily and reliably formed.

[0096] Specifically, the electric power density P1 of the first target 51 and the electric power density P2 of the second target 52 are appropriately set such that the ratio (P1 / P2) falls within the aforementioned range, for example, 0.1 W / cm². 2 The above, for example, 15W / cm 2 Set within the following range.

[0097] Next, the substrate sheet 2 is extracted from the extract roller 38 by driving the extract roller 38, the film forming roller 40, and the take-up roller 39. The substrate sheet 2 moves sequentially in the first film forming chamber 41 and the second film forming chamber 42 while in contact with the surface of the film forming roller 40. At this time, the substrate sheet 2 is cooled by contact with the surface of the film forming roller 40.

[0098] Near the first target 51, the sputtering gas is ionized by applying an electric current to the first target 51, generating ionized gas. Then, the ionized gas impacts the first target 51, and the target material of the first target 51 is ejected in the form of particles. The particles adhere (accumulate) to the substrate sheet 2, forming a first amorphous conductive film 81.

[0099] Next, near the second target 52, the sputtering gas is ionized by applying an electric current to the second target 52, generating ionized gas. Then, the ionized gas impacts the second target 52, and the target material of the second target 52 is ejected in the form of particles. The particles adhere (accumulate) to the first amorphous conductive film 81, forming the second amorphous conductive film 82.

[0100] The first amorphous conductive film 81 and the second amorphous conductive film 82 each contain the same conductive oxide as the main component, and sometimes their boundaries cannot be clearly observed.

[0101] Thus, an amorphous transparent conductive sheet 10 is obtained, which has a substrate sheet 2, a first amorphous conductive film 81 and a second amorphous conductive film 82 sequentially in the thickness direction.

[0102] Subsequently, the second amorphous conductive film 82 is crystallized (crystallization process). To crystallize the second amorphous conductive film 82, the amorphous transparent conductive sheet 10 is heated, for example. The heating temperature is, for example, 80°C or higher, preferably 100°C or higher, more preferably 150°C or higher, and also, for example, less than 200°C, preferably less than 180°C. The heating time is, for example, 1 minute or more, preferably 10 minutes or more, more preferably 30 minutes or more, further preferably 1 hour or more, and also, for example, 5 hours or less, preferably 3 hours or less. Alternatively, the amorphous transparent conductive sheet 10 may be placed at room temperature for a long time. For example, the amorphous transparent conductive sheet 10 may be placed in an atmosphere of 20°C or higher and 40°C or lower for 500 hours or more, preferably 1000 hours or more and 2000 hours or less.

[0103] Through the aforementioned heating or prolonged exposure to room temperature, the second amorphous conductive film 82 crystallizes, while the first amorphous conductive film 81 does not crystallize. This is because the ratio (P1 / P2) of the electric power density P1 of the first target 51 is within the aforementioned range (e.g., below 0.45). Therefore, the first amorphous conductive film 81 contains more impurities (e.g., hydrogen atoms and / or carbon atoms) compared to the second amorphous conductive film 82, thus maintaining its amorphous nature.

[0104] Thus, the first amorphous conductive film 81 forms the first region 6, and the second amorphous conductive film 82 forms the second region 7.

[0105] Thus, an amorphous transparent conductive sheet having a substrate sheet 2 and a transparent conductive layer 3 can be obtained, wherein the transparent conductive layer 3 has a first region 6 and a second region 7.

[0106] The transparent conductive sheet 1 is used in various applications, such as contact sensors, electromagnetic wave shielding components, dimming elements (voltage-driven dimming elements such as PDLC, PNLC, and SPD; current-driven dimming elements such as electrochromic (EC)), photoelectric conversion elements (electrodes of solar cell elements represented by organic thin-film solar cells and pigment-sensitized solar cells), hot-wire control components (near-infrared reflection and / or absorption components, far-infrared reflection and / or absorption components), antenna components (transparent antennas), heater components (transparent heaters), and image display devices.

[0107] (Effects of one implementation method)

[0108] Furthermore, the light-transmitting conductive layer 3 of the light-transmitting conductive sheet 1 has both low resistivity and suppresses cracks.

[0109] Specifically, the second crystalline region 7 is thicker than the amorphous region in the first region 6, thus reducing the resistivity of the transparent conductive layer 3. Furthermore, the thickness of the transparent conductive layer 3 exceeds 30 nm, thereby reducing its resistivity.

[0110] Furthermore, in the transparent conductive sheet 1, if the ratio of the thickness of the second region 7 to the thickness of the transparent conductive layer 3 is 0.73 or more, the transparent conductive layer 3 can ensure a lower resistivity and thus a lower surface resistance.

[0111] The contact sensor, dimming element, photoelectric conversion element, hot wire control component, antenna, electromagnetic wave shielding component, heater component, and image display device all have the above-mentioned light-transmitting conductive sheet 1, thus exhibiting excellent reliability.

[0112] (Modified Example)

[0113] In the variations, the same reference numerals are used to mark the same components and processes as in the first embodiment, and detailed descriptions are omitted. Furthermore, unless otherwise specified, the variations can achieve the same effects as the first embodiment. Moreover, a first embodiment and its variations can be appropriately combined.

[0114] In one embodiment, the light-transmitting conductive layer 3 includes a single first region 6, but for example, it may include multiple first regions 6. For example, the first region 6, the second region 7, and the first region 6 may be disposed on one side facing the thickness direction. Additionally, the light-transmitting conductive layer 3 includes a single second region 7, but for example, it may include multiple second regions 7. In this way, the light-transmitting conductive layer 3 may include multiple first regions 6 and multiple second regions 7.

[0115] For example, in this transparent conductive layer 3, a first region 6 and a second region 7 can be alternately arranged on one side facing the thickness direction. For example Figure 3 As shown, the first region 6, the second region 7, and the second region 7 are arranged sequentially on one side facing the thickness direction. In order to form... Figure 3 The transparent conductive layer 3 shown, for example, uses Figure 2The sputtering apparatus 30 is used to form a single first amorphous conductive film 81 and a single second amorphous conductive film 82. An amorphous transparent conductive sheet 10, wound by a take-up roller 39, is placed (rewound) onto the take-up roller 38 of the sputtering apparatus 30, and a third amorphous conductive film 83 and a fourth amorphous conductive film 84 are sequentially formed on one side facing the thickness direction of the second amorphous conductive film 82. The laminate is then heated or left at room temperature for an extended period. As a result, the second amorphous conductive film 82 and the fourth amorphous conductive film 84 crystallize, forming a second region 7. Meanwhile, the first amorphous conductive film 81 and the third amorphous conductive film 83 remain amorphous, forming a first region 6.

[0116] Therefore, the first region 6, the second region 7, the first region 6 and the second region 7 are arranged sequentially on one side facing the thickness direction.

[0117] In a modified example with multiple first regions 6, the thickness of the first region 6 is the sum of the thicknesses of the multiple first regions 6. In a modified example with multiple second regions 7, the thickness of the second region 7 is the sum of the thicknesses of the multiple second regions 7.

[0118] The substrate 2 may further include other functional layers. These functional layers may be, for example, dielectrics with a surface resistivity of, for example, 1 × 10⁻⁶. 6 Ω / □ or higher, preferably 1×10 8 Ω / □ or higher. Additionally, the functional layer contains resin and / or inorganic materials. The functional layer can be formed as a single layer or multiple layers, and can also be formed as a mixture of resin and inorganic materials. For example, such as... Figure 1 As shown by the virtual line, an anti-adhesion layer 25, which is formed of a mixture of resin and inorganic particles, can be disposed on the other side of the substrate film 13 in the thickness direction.

[0119] Although the resin layer of the present invention is not shown, it may be only the substrate layer 4, or it may be only the hard coating layer 5. Furthermore, the resin layer of the present invention may be a functional layer.

[0120] In one embodiment, the number of light-transmitting conductive layers 3 included in the light-transmitting conductive sheet 1 is one, although it may be two, for example, although not shown. In this case, the light-transmitting conductive layer 3, the substrate sheet 2, and the light-transmitting conductive layer 3 are arranged on the side facing the thickness direction. In other words, two light-transmitting conductive layers 3 sandwich one substrate sheet 2 in the thickness direction.

[0121] In one embodiment, the sputtering apparatus 30 includes a film-forming roller 40, or alternatively, a film-forming plate with a flat surface.

[0122] In one embodiment, a sputtering apparatus 30 having two film-forming chambers is used, but a sputtering apparatus 30 having only one film-forming chamber can also be used. For example, a first amorphous conductive film 81 is formed by a first sputtering, and an amorphous transparent conductive sheet 10 is wound up with a take-up roller 39 and placed (rewound) on the same sputtering apparatus 30 (with a take-up roller 38), and a second amorphous conductive film 82 is formed by a second sputtering. In this variation, for example, the ratio (P1 / P2) of the electric power density P1 of the first sputtering to the electric power density P2 of the second sputtering is the same as the ratio (P1 / P2) of the electric power density P1 of the first target 51 to the electric power density P2 of the second target 52.

[0123] In one embodiment, the temperature (surface temperature) of the film-forming roller 40 is set to cooling (below 20°C). In a variation, the film-forming roller 40 is heated. The temperature of the film-forming roller 40 is, for example, above 20°C and below 180°C.

[0124] In one embodiment, a sputtering apparatus 30 having a first film-forming chamber 41 and a second film-forming chamber 42 is used, but the number of film-forming chambers is not limited thereto. A sputtering apparatus 30 having three or more film-forming chambers may also be used. For example, a sputtering apparatus 30 having three film-forming chambers has a first film-forming chamber 41, a second film-forming chamber 42, and a third film-forming chamber (not shown).

[0125] Additionally, the third film-forming chamber may contain, for example, a third target (not shown), a third gas supply unit (not shown), and the outlet (not shown) of a third pump. When a third mixed gas is supplied as the sputtering gas, the third gas supply unit includes a third inactive gas supply unit (not shown) and a third reactive gas supply unit (not shown), which supply the inactive gas and the reactive gas to the third film-forming chamber, respectively. The transparent conductive layer 3 can be formed by applying an electric current to the first target 51, the second target 52, and the third target. However, in this modified example, a first amorphous conductive film 81 is formed by sputtering the first target 51, and a second amorphous conductive film 82 is formed by sputtering the second target 52 and the third target.

[0126] Example

[0127] The specific values ​​of mixing ratios (including proportions), physical property values, parameters, etc. used in the following description can be replaced with the corresponding upper limit values ​​(values ​​defined in the form of "less than" or "less than") or lower limit values ​​(values ​​defined in the form of "more than" or "exceeding") of the mixing ratios (including proportions), physical property values, parameters, etc., described in the "Specific Embodiments" above. Furthermore, unless otherwise specified, "parts" and "%" in the following description refer to mass measurements.

[0128] Example 1

[0129] On one side of the substrate layer 4, which is formed from a strip of PET film (manufactured by Mitsubishi Resin Co., Ltd., with a thickness of 50 μm), a UV-curable hard coating composition containing an acrylic resin is coated. This composition is then cured by irradiation with ultraviolet light, forming a hard coating layer 5 with a thickness of 2 μm. Thus, as... Figure 1 As shown, a substrate sheet 2 with a substrate layer 4 and a hard coating layer 5 is prepared.

[0130] Next, as Figure 2 As shown, the substrate sheet 2 is placed in the sputtering apparatus 30. The temperature of the film-forming roller 40 is set to -8°C. The first pump 71 and the second pump 72 are driven. In the sputtering apparatus 30, the materials of the first target 51 and the second target are both sintered bodies of indium oxide and tin oxide. The tin oxide concentration in the sintered body is 10% by mass.

[0131] Argon gas is supplied to the first film-forming chamber 41 from the first inactive gas supply unit 63, and oxygen gas is supplied to the first film-forming chamber 41 from the first reactive gas supply unit 64. The gas pressure in the first film-forming chamber 41 is 0.4 Pa. The oxygen-to-argon ratio R1 (capacity reference) in the mixed gas (total amount of argon and oxygen) in the first film-forming chamber 41 is 0.010. Electricity is applied to the first target 51 at an electric power density P1 to sputter the first target 51. The horizontal magnetic field strength on the first target 51 is 90 mT. The power supply applied to the first target 51 is DC.

[0132] Argon is supplied to the second film-forming chamber 42 from the second inactive gas supply unit 65, and oxygen is supplied to the second film-forming chamber 42 from the second reactive gas supply unit 66. The gas pressure in the second film-forming chamber 42 is 0.4 Pa. The oxygen-to-argon ratio R2 (capacity basis) in the mixed gas (total amount of argon and oxygen) in the second film-forming chamber 42 is 0.017. Electricity is applied to the second target 52 at an electric power density P2 to sputter the second target 52. The horizontal magnetic field strength on the second target 52 is 90 mT. DC power is used to power the second target 52. The ratio (P1 / P2) of the electric power density P1 of the first target 51 to the electric power density P2 of the second target 52 is 0.31.

[0133] Thus, a first amorphous conductive film 81 and a second amorphous conductive film 82 are sequentially formed along one side of the substrate sheet 2 in the thickness direction. This produces an amorphous transparent conductive sheet 10 having the substrate sheet 2, the first amorphous conductive film 81, and the second amorphous conductive film 82 sequentially along one side in the thickness direction.

[0134] Next, the amorphous transparent conductive sheet 10 was left to stand at 23°C for 1500 hours, and then heated at 155°C for 1.5 hours in a hot air oven. This yielded the transparent conductive sheet 1.

[0135] (Example 2, Example 4 to Comparative Example 5)

[0136] As shown in Table 1, the ratio of the electric power density P1 of the first target 51 to the electric power density P2 of the first target 51 (P1 / P2), the ratio of reactive gases R1 / R2, the total thickness of the light-transmitting conductive layer 3, etc., were changed. Otherwise, the process was the same as in Example 1 to obtain the light-transmitting conductive sheet 1.

[0137] (Example 3)

[0138] As shown in Table 1, by changing the ratio (P1 / P2) of the electric power density P1 of the first target 51 to the electric power density P2 of the first target 51, a first amorphous conductive film 81 and a second amorphous conductive film 82 are formed in the same manner as in Example 1, forming an amorphous transparent conductive sheet 10. After being wound up with a take-up roller 39, the amorphous transparent conductive sheet 10 is placed (rewound) in the sputtering apparatus 30 to form a third amorphous conductive film 83 and a fourth amorphous conductive film 84. Subsequently, it is left to stand at 23°C for 1500 hours, and then heated in a hot air oven at 155°C for 1.5 hours.

[0139] (Thickness measurement, crystallinity confirmation, evaluation, etc.)

[0140] The following items were evaluated for the light-transmitting conductive sheet 1 of each embodiment and each comparative example.

[0141] The results are recorded in Table 1.

[0142] (Thickness of the transparent conductive layer and determination of amorphous and crystalline materials)

[0143] After adjusting the cross-section of the transparent conductive sheet 1 using the FIB microsampling method, FE-TEM observation of the cross-section was performed. Using TEM images taken at a magnification of 200,000x, the thickness of the black region (first region 6) and the gray region (second region 7) of the transparent conductive layer 3 were measured. Furthermore, these thicknesses were combined to obtain the total thickness of the transparent conductive layer 3.

[0144] Furthermore, cross-sectional TEM observations were performed at high magnification (2 million times) in both the black and gray regions. In the gray region, lattice patterns were observed throughout the entire area during cross-section, indicating that it is crystalline and is the second region 7. On the other hand, in the black region, lattice patterns were not observed throughout the entire area during cross-section, or lattice patterns were observed in a narrow area during cross-section, but these lattice patterns were small areas and therefore amorphous, indicating that it is the first region 6.

[0145] The apparatus and measurement conditions are shown below.

[0146] FIB device: Hitachi FB2200, accelerating voltage: 10kV

[0147] FE-TEM device: JEOL JEM-2800, accelerating voltage: 200kV

[0148] The TEM image of Example 2 is shown below. Figure 4 The TEM image of Example 3 is shown below. Figure 5 .

[0149] (Surface resistivity)

[0150] The surface resistance of the transparent conductive layer 3 was determined using the four-terminal method based on JIS K7194 (1994). The surface resistance was evaluated according to the following criteria.

[0151] <Benchmark>

[0152] ◎: Surface resistivity is below 20Ω / □.

[0153] 〇: Surface resistance exceeds 20Ω / □ and is below 45Ω / □.

[0154] △: Surface resistance exceeds 45Ω / □ but is below 65Ω / □.

[0155] ×: Surface resistance exceeds 65Ω / □.

[0156] (Resistivity)

[0157] The resistivity is obtained by multiplying the surface resistance of the transparent conductive layer 3 by the thickness of the transparent conductive layer 3.

[0158] Resistivity is evaluated according to the following criteria.

[0159] <Evaluation Criteria>

[0160] ◎: Resistivity is 2.2 × 10⁻⁶ -4 Below Ω·cm.

[0161] 〇: Resistivity exceeds 2.2×10 -4 Ω·cm and is 2.8×10 -4 Below Ω·cm.

[0162] ×: Resistivity exceeds 2.8 × 10⁻⁶ -4 Ω·cm.

[0163] (crack)

[0164] The transparent conductive sheet 1 was cut into 5cm × 50cm pieces. Next, 15 sections, each 5cm × 10cm in top view, were identified, and the surface of the transparent conductive layer 3 in each section was visually observed. The crack level of the transparent conductive layer 3 was evaluated according to the following criteria.

[0165] <Evaluation Criteria>

[0166] 〇: The number of crack zones observed is more than 0 and less than 6.

[0167] △: The observed crack zones are more than 7 and less than 12.

[0168] ×: More than 13 crack zones were observed.

[0169] [Table 1]

[0170]

[0171] It should be noted that the above-described invention is provided as an illustrative embodiment of the present invention, and is merely an example and not intended to be limiting. Variations of the invention that will be apparent to those skilled in the art are included in the foregoing claims.

[0172] Industrial availability

[0173] Transparent conductive sheets can be used in contact sensors, electromagnetic wave shielding components, dimming elements, photoelectric conversion elements, hot wire control components, antenna components, heater components, image display devices, etc.

[0174] Explanation of reference numerals in the attached figures

[0175] 1. Transparent conductive sheet

[0176] 2. Substrate sheet

[0177] 3 Transparent conductive layer

[0178] 6. First District

[0179] 7 Second Area

[0180] 11 Substrate

Claims

1. A light-transmitting conductive sheet, characterized in that, The side facing the thickness direction has a resin layer and a light-transmitting conductive layer in sequence. The transparent conductive layer comprises a first region and a second region sequentially on the side facing the thickness direction. The material of the light-transmitting conductive layer is a metal oxide. The main region of the first area is amorphous. The second region is mainly composed of crystalline material. The area ratio of the main area of ​​the first region is greater than 0.6 and less than 1. The area ratio of the main area of ​​the second region is greater than 0.7 and less than 1. The second region is thicker than the first region. The thickness of the transparent conductive layer is greater than 75 nm and less than 500 nm. The ratio of the thickness of the second region to the thickness of the first region is more than 2 and less than 10.

2. The transparent conductive sheet according to claim 1, characterized in that, The thickness of the second region is at least 0.73 times the thickness of the transparent conductive layer.

3. The transparent conductive sheet according to claim 1 or 2, characterized in that, The transparent conductive layer is made of a composite oxide containing indium and tin.

4. A contact sensor, characterized in that, A transparent conductive sheet comprising any one of claims 1 to 3.

5. A dimming element, characterized in that, A transparent conductive sheet comprising any one of claims 1 to 3.

6. A photoelectric conversion element, characterized in that, A transparent conductive sheet comprising any one of claims 1 to 3.

7. A hot wire control component, characterized in that, A transparent conductive sheet comprising any one of claims 1 to 3.

8. An antenna, characterized in that, A transparent conductive sheet comprising any one of claims 1 to 3.

9. An electromagnetic wave shielding component, characterized in that, A transparent conductive sheet comprising any one of claims 1 to 3.

10. An image display device, characterized in that, A transparent conductive sheet comprising any one of claims 1 to 3.

Images