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EP-4738390-A1 - TRANSPARENT CONDUCTIVE FILM

EP4738390A1EP 4738390 A1EP4738390 A1EP 4738390A1EP-4738390-A1

Abstract

Provided is a transparent conductive film excellent in translucency in a near-infrared region. The transparent conductive film according to one embodiment of the present invention is a transparent conductive film including: a substrate; and a conductive layer arranged on at least one side of the substrate, wherein the transparent conductive film has a surface resistance value of 200 Ω/□ or less, and wherein the transparent conductive film has a light transmittance in a wavelength region of from 780 nm to 2,500 nm of 85% or more.

Inventors

  • MIZUKAWA, YUKI
  • KONO, FUMIHIKO

Assignees

  • Nitto Denko Corporation

Dates

Publication Date
20260506
Application Date
20240415

Claims (8)

  1. A transparent conductive film, comprising: a substrate; and a conductive layer arranged on at least one side of the substrate, wherein the transparent conductive film has a surface resistance value of 200 Ω/□ or less, and wherein the transparent conductive film has a maximum value of a light transmittance in a wavelength region of from 780 nm to 2,500 nm of 85% or more.
  2. The transparent conductive film according to claim 1, wherein the transparent conductive film has a surface resistance value of 100 Ω/□ or less.
  3. The transparent conductive film according to claim 1, wherein the transparent conductive film has a ratio (T905/T555) of a light transmittance (T905) at a wavelength of 905 nm to a light transmittance (T555) at a wavelength of 555 nm of more than 0.95 and 1.1 or less.
  4. The transparent conductive film according to claim 1, wherein the transparent conductive film has a maximum value of a light transmittance in a wavelength region of from 900 nm to 1,600 nm of 85% or more.
  5. The transparent conductive film according to claim 1, wherein the transparent conductive film has a light transmittance at a wavelength of 905 nm of 85% or more.
  6. The transparent conductive film according to claim 1, wherein the conductive layer contains a fiber-based conductive material and a polymer matrix.
  7. The transparent conductive film according to claim 6, wherein the fiber-based conductive material is a metal nanowire.
  8. The transparent conductive film according to claim 1, wherein the transparent conductive film is a transparent conductive film for a transparent heater.

Description

Technical Field The present invention relates to a transparent conductive film. Background Art A transparent conductive film obtained by forming a metal oxide layer such as an indium-tin composite oxide layer (ITO layer) on a resin film has heretofore been frequently used as a transparent conductive film to be used in, for example, an electrode of a touch sensor. However, there is a problem in that the transparent conductive film obtained by forming a metal oxide layer has low translucency in a near-infrared region, and a desired resistance value thereof is hardly obtained in consideration of translucency. Citation List Patent Literature [PTL 1] JP 2009-505358 A Summary of Invention Technical Problem The present invention has been made to solve the above-mentioned problem, and a primary object of the present invention is to provide a transparent conductive film excellent in translucency in a near-infrared region. Solution to Problem [1] According to one embodiment of the present invention, there is provided a transparent conductive film, including: a substrate; and a conductive layer arranged on at least one side of the substrate, wherein the transparent conductive film has a surface resistance value of 200 Ω/□ or less, and wherein the transparent conductive film has a maximum value of a light transmittance in a wavelength region of from 780 nm to 2,500 nm of 85% or more.[2] The transparent conductive film according to the above-mentioned item [1] may have a surface resistance value of 100 Ω/□ or less.[3] The transparent conductive film according to the above-mentioned item [1] or [2] may have a ratio (T905/T555) of a light transmittance (T905) at a wavelength of 905 nm to a light transmittance (T555) at a wavelength of 555 nm of more than 0.95 and 1.1 or less.[4] The transparent conductive film according to any one of the above-mentioned items [1] to [3] may have a maximum value of a light transmittance in a wavelength region of from 900 nm to 1,600 nm of 85% or more.[5] The transparent conductive film according to any one of the above-mentioned items [1] to [4] may have a light transmittance at a wavelength of 905 nm of 85% or more.[6] In the transparent conductive film according to any one of the above-mentioned items [1] to [5], the conductive layer may contain a fiber-based conductive material and a polymer matrix.[7] The transparent conductive film according to the above-mentioned item [6] may be a metal nanowire.[8] The transparent conductive film according to any one of the above-mentioned items [1] to [7] may be a transparent conductive film for a transparent heater. Advantageous Effects of Invention According to the embodiment of the present invention, the transparent conductive film excellent in translucency in a near-infrared region can be provided. Brief Description of Drawings FIG. 1 is a schematic sectional view of a transparent conductive film according to one embodiment of the present invention. Description of Embodiments Embodiments of the present invention are described below. However, the present invention is not limited to these embodiments. A. Overall Configuration of Transparent Conductive Film FIG. 1 is a schematic sectional view of a transparent conductive film according to one embodiment of the present invention. A transparent conductive film 100 includes a substrate 10 and a conductive layer 20 arranged on at least one side of the substrate 10. In one embodiment, the conductive layer 20 contains a fiber-based conductive material 21. Examples of the fiber-based conductive material include metal nanowires and carbon nanotubes. Of those, metal nanowires are preferably used. The transparent conductive film may further include any appropriate other layer (not shown). In one embodiment, the transparent conductive film 100 includes a protective layer 30 arranged on the conductive layer 20 on a side opposite to the substrate 10. The protective layer 30 may be a layer that protects the fiber-based conductive material 21. In the embodiment of the present invention, the durability of the conductive layer 20 can be improved by arranging the protective layer 30. More specifically, while the conductive layer including the fiber-based conductive material (e.g., metal nanowires) is characterized by low scratch resistance, low humidity durability, and the like, those problems are solved and the durability of the conductive layer (consequently, the durability of the transparent conductive film) can be improved by arranging the protective layer. The conductive layer 20 may contain a component for forming the protective layer 30 (e.g., a resin for forming the protective layer). The surface resistance value of the transparent conductive film is 200 Ω/□ or less, preferably from 0.01 Ω/□ to 200 Ω/□, more preferably from 1 Ω/□ to 180 Ω/□, particularly preferably from 5 Ω/□ to 150 Ω/□, most preferably from 10 Ω/□ to 100 Ω/□. The surface resistance value of the transparent conductive film may be 100 Ω/□ or