JP5425351B1 - Light transmissive conductive film, method for producing the same, and use thereof - Google Patents

Abstract

The present invention includes (A) a light transmissive support layer, (B) an optical adjustment layer, and (C) a light transmissive conductive layer containing indium tin oxide, and the optical adjustment layer (B) includes the light transmission layer. The transparent support layer (A) is disposed on at least one surface of the transparent support layer (A) directly or via one or more other layers, and the transparent conductive layer (C) is the transparent support layer (A). A light-transmitting conductive film disposed on at least one of the surfaces via at least the optical adjustment layer (B), wherein the optical adjustment layer (B) contains zirconia and has a thickness of 0. The ratio of the peak near 2θ = 28 ° derived from zirconia to the peak of the (222) plane derived from indium tin oxide is 0.1 to 1.0 in the XRD measurement by a thin film method of 4 to 3 μm. In a light-transmitting conductive film characterized by To.

Description

  The present invention relates to a light-transmitting conductive film, a manufacturing method thereof, and an application thereof.

  As a light-transmitting conductive film mounted on the touch panel, a light-transmitting conductive layer containing indium oxide is disposed on at least one surface of a light-transmitting support layer made of plastic or the like, directly or via another layer. Many such light-transmitting conductive films are used.

  When a touch panel is constituted using these light-transmitting conductive films as electrodes, it is necessary to satisfy various required characteristics at the same time. The following are known as such required characteristics.

  Although the light-transmitting conductive layer may be disposed as a grid-like electrode, when the grid-like structure is visible from the user's viewpoint, the visibility as a touch panel is impaired, which is not preferable. Note that the fact that such a phenomenon has been eliminated is sometimes referred to as “index matching is good”.

  Further, in the process of manufacturing the touch panel by incorporating the light transmissive conductive film, the light transmissive conductive film is exposed to a predetermined chemical treatment. Therefore, the light-transmitting conductive film having poor chemical resistance has a problem that it is damaged by chemical treatment in the manufacturing process.

  Furthermore, for example, when forming the electrode having the above-described lattice shape or the like, a so-called etching process is performed in which the light-transmitting conductive layer is removed only in a predetermined region by chemical treatment, and as a result Forming a shaped electrode has been performed. Accordingly, the light-transmitting conductive film that is difficult to be etched by the etching process (that is, the light-transmitting conductive layer is difficult to be removed in a desired region) has low production efficiency in the process of manufacturing the touch panel, and is easily etched excessively. (In other words, the light-transmitting conductive layer is removed unintentionally even in a region different from the desired region.) With a light-transmitting conductive film, it is difficult to form the light-transmitting conductive layer into a desired shape. There are problems such as.

  Thus, as a light-transmitting conductive film mounted on a touch panel, (1) index matching, (2) chemical resistance, and (3) light-transmitting conductivity excellent in any of etching properties. There is a need for films.

JP 2010-6647 A JP 2007-42284 A

  The present invention relates to a light-transmitting conductive film comprising (A) a light-transmitting support layer, (B) an optical adjustment layer, and (C) a light-transmitting conductive layer containing indium oxide. , (2) To improve the balance between chemical resistance and (3) etching property.

The inventors of the present invention have made extensive studies, adopting zirconia as the optical adjustment layer (B) and having a thickness of 0.4 to 3 μm, and the entire film in XRD measurement by a thin film method. The above problem can be solved by setting the ratio of the peak near 2θ = 28 ° derived from zirconia to the peak of the (222) plane derived from indium oxide to be 0.1 to 1.0. I found it. The present invention has been completed by further various studies based on this new knowledge, and is as follows.
Item 1
(A) a light transmissive support layer;
(B) an optical adjustment layer; and (C) a light-transmitting conductive layer containing indium oxide,
The optical adjustment layer (B) is disposed on at least one surface of the light transmissive support layer (A) directly or via one or more other layers, and the light transmissive conductive layer (C ) Is a light transmissive conductive film disposed on at least one surface of the light transmissive support layer (A) via at least the optical adjustment layer (B):
The optical adjustment layer (B) contains zirconia and has a thickness of 0.4 to 3 μm; and in XRD measurement by a thin film method, it originates from indium oxide having a peak around 2θ = 28 ° derived from zirconia. The ratio of the (222) plane to the peak is 0.1 to 1.0.
Item 2
Item 2. The light transmissive conductive material according to Item 1, wherein an average surface roughness Ra of the surface of the optical adjustment layer (B) on the side opposite to the light transmissive support layer (A) is 0.4 to 2.0 nm. Sex film.
Item 3
Item 3. The light transmissive conductive film according to Item 1 or 2, wherein the zirconia has an average particle size of 10 to 40 nm.
Item 4
Item 4. The light according to any one of Items 1 to 3, wherein the light-transmitting conductive layer (C) contains particles containing indium oxide, and the average particle size of the particles is 3.0 to 8.0 nm. Transparent conductive film.
Item 5
Item 5. The light transmissive property according to any one of Items 1 to 4, wherein the light transmissive conductive layer (C) can be obtained by heating a layer containing indium oxide in the atmosphere at 90 to 160 ° C for 10 to 120 minutes. Conductive film.
Item 6
Item 6. The light transmissive conductive film according to any one of Items 1 to 5, wherein the light transmissive conductive layer (C) contains indium tin oxide.
Item 7
Item 7. A touch panel comprising the light transmissive conductive film according to any one of items 1 to 6.

  According to the present invention, (1) index matching, (2) chemical resistance, and (3) an improved balance of etching properties, (A) a light transmissive support layer, (B) an optical adjustment layer, and ( C) A light-transmitting conductive film containing a light-transmitting conductive layer containing indium oxide can be provided.

It is sectional drawing which shows the light-transmitting conductive film of this invention by which the optical adjustment layer (B) and the light-transmitting conductive layer (C) are arrange | positioned in this order on the single side | surface of a light-transmitting support layer (A). is there. It is sectional drawing which shows the light transmissive conductive film of this invention by which the optical adjustment layer (B) and the light transmissive conductive layer (C) are arrange | positioned in this order on both surfaces of the light transmissive support layer (A). is there. The first optical adjustment layer (B) and the light transmissive conductive layer (C) are disposed in this order on one surface of the light transmissive support layer (A), and the second surface is disposed on the other surface. It is sectional drawing which shows the optically transparent conductive film of this invention in which the optical adjustment layer (B) of this is directly arrange | positioned. The light-transmissive conductive layer of the present invention, in which the optical adjustment layer (B), the undercoat layer (D), and the light-transmissive conductive layer (C) are arranged in this order on one side of the light-transmissive support layer (A). It is sectional drawing which shows a property film. The light-transmitting conductive layer of the present invention, in which the optical adjustment layer (B), the undercoat layer (D), and the light-transmitting conductive layer (C) are arranged in this order on both surfaces of the light-transmitting supporting layer (A). It is sectional drawing which shows a property film. The first optical adjustment layer (B), the undercoat layer (D) and the light transmissive conductive layer (C) are arranged in this order on one surface of the light transmissive support layer (A), and It is sectional drawing which shows the translucent conductive film of this invention by which the 2nd optical adjustment layer (B) is directly arrange | positioned on the other surface.

1. Light transmissive conductive film The light transmissive conductive film of the present invention comprises:
(A) a light transmissive support layer;
(B) an optical adjustment layer; and (C) a light-transmitting conductive layer containing indium oxide,
The optical adjustment layer (B) is disposed on at least one surface of the light transmissive support layer (A) directly or via one or more other layers, and the light transmissive conductive layer (C ) Is a light transmissive conductive film disposed on at least one surface of the light transmissive support layer (A) via at least the optical adjustment layer (B):
The optical adjustment layer (B) contains zirconia and has a thickness of 0.4 to 3 μm; and in XRD measurement by a thin film method, it originates from indium oxide having a peak around 2θ = 28 ° derived from zirconia. The ratio of the (222) plane to the peak is 0.1 to 1.0.

  In the present invention, “light-transmitting” means having a property of transmitting light (translucent). “Light transmissivity” includes transparency. “Light transmissivity” means, for example, the property that the total light transmittance is 80% or more, preferably 85% or more, more preferably 87% or more. In the present invention, the total light transmittance is measured based on JIS-K-7105 using a haze meter (trade name: NDH-2000 manufactured by Nippon Denshoku Co., Ltd. or equivalent).

  In this specification, when mentioning the relative positional relationship between two layers among a plurality of layers arranged on one surface of the light transmissive support layer (A), the light transmissive support layer (A) is used as a reference. One layer having a large distance from the light transmissive support layer (A) is referred to as “upper layer” and the like, and the other layer having a small distance from the light transmissive support layer (A) is referred to as “lower layer”. And so on.

  In the present invention, the thickness of each layer is determined using a commercially available reflection spectral film thickness meter (Otsuka Electronics, FE-3000, or equivalent) unless otherwise specified in the following description of each layer. Alternatively, the thickness of each layer may be obtained by observation using a commercially available transmission electron microscope. Specifically, the light-transmitting conductive film is thinly cut in a direction perpendicular to the film surface using a microtome or a focus ion beam, and the cross section is observed.

  In FIG. 1, the one aspect | mode of the transparent electroconductive film of this invention is shown. In this embodiment, the optical adjustment layer (B) and the light transmissive conductive layer (C) are arranged in this order on one surface of the light transmissive support layer (A).

  FIG. 2 shows another embodiment of the light transmissive conductive film of the present invention. In this embodiment, the optical adjustment layer (B) and the light transmissive conductive layer (C) are arranged in this order on both surfaces of the light transmissive support layer (A).

1.1 Light transmissive support layer (A)
In the present invention, the light transmissive support layer refers to a light transmissive conductive film containing a light transmissive conductive layer, which plays a role of supporting the layer containing the light transmissive conductive layer. Although it does not specifically limit as a light transmissive support layer (A), For example, in the light transmissive conductive film for touch panels, what is normally used as a light transmissive support layer can be used.

  Although the raw material of a light-transmissive support layer (A) is not specifically limited, For example, glass, various organic polymers, etc. can be mentioned. The organic polymer is not particularly limited. For example, polyester resin, acetate resin, polyether resin, polycarbonate resin, polyacrylic resin, polymethacrylic resin, polystyrene resin, polyolefin resin, polyimide resin, etc. Examples include resins, polyamide resins, polyvinyl chloride resins, polyacetal resins, polyvinylidene chloride resins, and polyphenylene sulfide resins. Although it does not specifically limit as polyester-type resin, For example, a polyethylene terephthalate (PET), a polyethylene naphthalate (PEN), etc. are mentioned. The material of the light transmissive support layer (A) is preferably a polyester resin, and particularly preferably PET. The light transmissive support layer (A) may be composed of any one of these, or may be composed of a plurality of types.

  Although the thickness of a light-transmissive support layer (A) is not specifically limited, For example, the range of 2-300 micrometers is mentioned.

1.2 Optical adjustment layer (B)
In the light transmissive conductive film of the present invention, the optical adjustment layer (B) is disposed directly or via one or more other layers on at least one surface of the light transmissive support layer (A). The optical adjustment layer (B) is preferably disposed directly on the surface of the light transmissive support layer (A).

  One layer of the optical adjustment layer (B) may be disposed. Alternatively, two or more layers may be arranged adjacent to each other or separated from each other via other layers.

  The optical adjustment layer (B) may be directly disposed on both surfaces of the light transmissive support layer (A).

When two or more layers of the optical adjustment layer (B) are arranged adjacent to each other, the optical adjustment layer located below has a higher refractive index than the optical adjustment layer located above. Also good.
By adopting such a configuration, an optical interference action is generated between two layers having different refractive indexes, which is preferable because the transmittance of the light-transmitting conductive film is improved.

  In the present invention, the optical adjustment layer refers to a layer that plays a role of improving the transmittance of the light transmissive film by optical interference. Although it does not specifically limit as an optical adjustment layer (B), For example, what is normally used as an optical adjustment layer in the transparent conductive film for touchscreens can be used.

  The optical adjustment layer (B) contains zirconia. The zirconia contained in the optical adjustment layer (B) is preferably particulate, more preferably the average particle size is 10 to 40 nm, and still more preferably the average particle size is 10 to 30 nm. When the average particle size of zirconia is smaller than 40 nm, the etching property is further improved, and when it is larger than 10 nm, the dispersibility is further improved and the workability is further improved.

  The light-transmitting conductive film of the present invention shows a peak around 2θ = 28 ° derived from zirconia of the optical adjustment layer (B) in XRD measurement by a thin film method.

In the present invention, XRD measurement by the thin film method is performed as follows.
The X-ray diffractometer is measured by a thin film method using a Rigaku thin film evaluation sample horizontal X-ray diffractometer SmartLab or equivalent. A parallel beam optical arrangement is used, and CuKα rays (wavelength: 1.54186Å) are used as a light source at a power of 40 kV and 30 mA. The incident side slit system uses a solar slit of 5.0 °, a height control slit of 10 mm, and an incident slit of 0.1 mm, and the light receiving side slit has a parallel slit analyzer (PSA) of 0.114 deg. Is used. The detector uses a scintillation counter. The sample stage uses a porous adsorption sample holder, and a sample is adsorbed and fixed by a pump. When the X-ray incident angle is 0.50 ° and sufficient detection sensitivity is not obtained, the incident angles are 0.40 °, 0.45 °, 0.55 °, and 0.60 °. The result that the peak of interest is the strongest is adopted. The step interval and the measurement speed are appropriately adjusted so that the X-ray diffraction pattern can be recognized. Preferably, the measurement is performed at a step interval of 0.01 ° and a measurement speed of 3.0 ° / min. The measurement range is measured from 10 ° to 60 °. The obtained X-ray diffraction pattern does not need to be monochromatic, and each peak intensity uses a value obtained by subtracting the background.

In the present invention, the average particle diameter of zirconia is determined by observation with a transmission electron microscope. Specifically, a light-transmitting conductive film is cut into thin pieces using a microtome or a focus ion beam, and the cross section is observed. Thus, the length in the long axis direction of 14 particles obtained by removing the upper 3 particles and the lower 3 particles in the long axis direction length from 20 randomly selected particles that can be visually recognized. Is the average particle diameter. As a result of observation with a transmission electron microscope, when a predetermined amount of particles cannot be visually recognized, observation is performed in different regions of the same sample.
When the zirconia particles cannot be distinguished from other particles, the particles are subjected to elemental analysis by EDX or EELS to identify the zirconia particles.

  The thickness of the optical adjustment layer (B) is 0.4 to 3 μm, preferably 0.5 to 2.5 μm, more preferably 1 to 2 μm. When the thickness of the optical adjustment layer (B) is smaller than 3 μm, the index matching property is further improved. On the other hand, when it is larger than 0.4 μm, a peak derived from zirconia can be confirmed more easily, and the index matching property is further improved.

  In the present invention, the thickness of the optical adjustment layer (B) is measured as follows. Obtained by observation with a transmission electron microscope. Specifically, a light-transmitting conductive film is cut into thin pieces using a microtome or a focus ion beam, and the cross section is observed.

  The optical adjustment layer (B) is preferably etched when the average surface roughness Ra on the surface opposite to the light transmissive support layer (A) is 0.4 to 2.0 nm in terms of etching properties. If it is 5-1.8 nm, it is more preferable, and if it is 0.5-1.5 nm, it is still more preferable.

  In the present invention, the average surface roughness Ra means an arithmetic average of roughness measured using a scanning probe microscope. In detail, the average surface roughness Ra in the present invention is obtained by measuring a 1 μm square measurement surface in a predetermined contact mode using a commercially available scanning probe microscope (Shimadzu Corporation, SPM-9700, or equivalent). It is the value which averaged the absolute deviation from the average line obtained by scanning with a probe (OMLY-TR800-PSA-1 spring constant 0.15 N / m manufactured by OLYMPUS).

  The optical adjustment layer (B) is not particularly limited as long as the effect of the present invention is exhibited, but may further contain other components in addition to zirconia. The other components are not particularly limited as long as the effects of the present invention are exhibited. For example, acrylic resins, silicone resins, melamine resins, and alkyd resins; and colloidal particles such as silica, zirconia, titania, and alumina. Etc. In addition to zirconia, the optical adjustment layer (B) may further contain any one of them, or may further contain a plurality of types.

  When the optical adjustment layer (B) further contains other components in addition to zirconia, the content ratio of zirconia in the whole is not particularly limited as long as the effect of the present invention is exhibited, but is preferably 20% by weight or more. is there.

  The method of disposing the optical adjustment layer (B) is not particularly limited, and examples thereof include a method of applying to a film and curing with heat, and a method of curing with active energy rays such as ultraviolet rays and electron beams. . From the viewpoint of productivity, a method of curing with ultraviolet rays is preferable.

1.3 Light transmissive conductive layer (C)
The light transmissive conductive layer (C) contains indium oxide. The light transmissive conductive layer (C) may further contain a dopant in addition to indium oxide. The dopant is not particularly limited, and examples thereof include tin oxide, zinc oxide, cerium oxide, gadolinium oxide, silicon oxide, and titanium oxide. In addition to indium oxide, the light transmissive conductive layer (C) may contain these alone or as a dopant. As the light-transmitting conductive layer (C), a layer containing indium tin oxide (ITO) can be cited as a preferred example at present, but indium oxide containing other dopants as necessary. A layer containing can also be used.

Indium tin oxide is indium oxide doped with tin. As indium tin oxide, indium tin oxide obtained by using indium (III) oxide (In ₂ O ₃ ) and tin (IV) oxide (SnO ₂ ) is preferable. In this case, the addition amount of SnO ₂ is not particularly limited, and examples thereof include 1 to 15% by weight, preferably 2 to 10% by weight, and more preferably 3 to 8% by weight. In addition, the light-transmitting conductive layer (C) may contain a dopant in which another dopant is further added to indium tin oxide in a range where the total amount of dopant does not exceed the numerical range shown on the left. Although it does not specifically limit as another dopant in the left, For example, zinc, cerium, gadolinium, silicon, titanium, etc. are mentioned.

  The light transmissive conductive layer (C) may contain any one of the various indium tin oxides described above, or may contain a plurality of types.

  The light transmissive conductive layer (C) may contain particles containing indium oxide. The average particle diameter of the particles is not particularly limited as long as the effect of the present invention is exhibited, but is preferably 3.0 to 8.0 nm in that the specific resistance tends to be small, and 3.5 to 6. It is more preferable if it is 5 nm, and it is more preferable if it is 3.5-6.0 nm. As particles containing indium oxide, indium tin oxide particles can be cited as a preferred example at present, but particles of indium oxide containing other dopants can be used as necessary.

  In the present invention, the average particle diameter of the particles containing indium oxide is 0.5 μm 2 in a predetermined contact mode using a commercially available scanning probe microscope (Shimadzu Corporation, SPM-9700, or equivalent). The measurement surface is obtained from an image obtained by scanning the probe with a probe (OMLY TRUS-PSA-1 spring constant 0.15 N / m, or equivalent) manufactured by OLYMPUS. Specifically, particle diameters are classified every 1 nm for particles of 1 nm to 30 nm from the observed image, the number of particles integrated in each particle diameter is examined, and the particle diameter of D50 in the particle size distribution is defined as the average particle diameter. To do.

  The light transmissive conductive layer (C) is not particularly limited, but may be a crystalline or amorphous body, or a mixture thereof.

  The light-transmitting conductive film of the present invention has a (222) plane peak around 2θ = 30.5 ° derived from indium oxide contained in the light-transmitting conductive layer (C) in XRD measurement by a thin film method. Shown in Since this peak is derived from indium oxide itself, the same peak is naturally observed even when the above various dopants are added to indium oxide. Further, the peak on the (222) plane is the strongest of all the peaks derived from indium oxide (or a mixture of indium oxide and dopant when a dopant is further added).

  Furthermore, in the light-transmitting conductive film of the present invention, the ratio of the peak around 2θ = 28 ° derived from zirconia to the peak of the (222) plane derived from indium oxide is 0.1 in the XRD measurement by the thin film method. -1.0. For this reason, the light-transmitting conductive film of the present invention has an improved balance of (1) index matching, (2) chemical resistance, and (3) etching property.

  The light-transmitting conductive layer (C) having the above-mentioned characteristics is obtained by heat treatment of indium oxide (or a mixture of indium oxide and dopant when a dopant is further added; hereinafter, this mixture and indium oxide are collectively referred to as “ It is sometimes referred to as “indium oxide or the like”). The conditions for this heat treatment can be appropriately set within the range in which the light-transmitting conductive layer (C) having the above characteristics can be obtained, and are not particularly limited. For example, heating in the atmosphere at 90 to 160 ° C. for 10 to 120 minutes Processing conditions etc. are mentioned. Specifically, heat treatment conditions in the atmosphere at 140 ° C. for 60 minutes can be given. By heat-treating a raw material made of indium oxide or the like or a raw material containing indium oxide or the like in the atmosphere at 90 to 160 ° C. for 10 to 120 minutes, crystallization of indium oxide or the like is further promoted, and the above characteristics are obtained. The light-transmitting conductive layer (C) has a crystal body such as indium oxide or a mixture of a crystal body such as indium oxide and an amorphous body such as indium oxide. Although not particularly limited, the light-transmitting conductive layer (C) having the above characteristics is formed in the atmosphere at 90 to 160 ° C., 10 to 10 after forming a layer containing indium oxide or the like on the underlying layer. It can be obtained by heat treatment for 120 minutes.

  The light transmissive conductive layer (C) is disposed on at least one surface of the light transmissive support layer (A) via at least the optical adjustment layer (B).

  The thickness of the light transmissive conductive layer (C) is 5 to 200 nm, preferably 10 to 100 nm, and more preferably 15 to 50 nm. Moreover, as a transparent conductive film for capacitive touch panels, the thickness of the transparent conductive layer (C) is 15 to 40 nm, preferably 15 to 38 nm, and more preferably 17 to 35 nm.

  The method for forming the light transmissive conductive layer (C) may be either wet or dry.

  The method for forming the light transmissive conductive layer (C) is not particularly limited, and examples thereof include an ion plating method, a sputtering method, a vacuum deposition method, a CVD method, and a pulse laser deposition method. As a method for forming the light transmissive conductive layer (C), a sputtering method is preferable.

When the light transmissive conductive layer (C) is formed by a sputtering method, it is not particularly limited. For example, by forming an oxygen partial pressure of 7.0 × 10 ⁻³ Pa or more, in XRD measurement by a thin film method, zirconia The ratio of the peak near 2θ = 28 ° derived to the peak of the (222) plane derived from indium oxide can be appropriately adjusted to 0.1 to 1.0.

1.4 Undercoat layer (D)
The light transmissive conductive film of the present invention has an undercoat layer directly or via one or more other layers on the surface of the light transmissive support layer (A) where the light transmissive conductive layer (C) is disposed. (D) may be arranged. When the undercoat layer (D) is disposed, at least one of the light transmissive conductive layers (C) is supported by the light transmissive support through at least the undercoat layer (D) and the optical adjustment layer (B). It is arranged on the surface of the layer (A). In this case, at least one of the light transmissive conductive layers (C) may be disposed adjacent to the undercoat layer (D). In this case, the undercoat layer (D) is usually disposed closer to the light transmissive conductive layer (C) than the optical adjustment layer (B).

  In FIG. 4, the one aspect | mode of the transparent electroconductive film of this invention is shown. In this embodiment, the optical adjustment layer (B), the undercoat layer (D), and the light transmissive conductive layer (C) are arranged adjacent to each other in this order on one surface of the light transmissive support layer (A). ing.

  In FIG. 5, the one aspect | mode of the transparent electroconductive film of this invention is shown. In this embodiment, the optical adjustment layer (B), the undercoat layer (D), and the light transmissive conductive layer (C) are arranged adjacent to each other in this order on both surfaces of the light transmissive support layer (A). .

  In FIG. 6, the one aspect | mode of the transparent electroconductive film of this invention is shown. In this embodiment, the first optical adjustment layer (B), the undercoat layer (D), and the light transmissive conductive layer (C) are adjacent to each other in this order on one surface of the light transmissive support layer (A). The second optical adjustment layer (B) is directly arranged on the other surface.

  Although the material of an undercoat layer (D) is not specifically limited, For example, you may have a dielectric property. The material for the undercoat layer (D) is not particularly limited. For example, silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, silicon alkoxide, alkylsiloxane and its condensate, polysiloxane, silsesquioxane, and Examples include polysilazane. The undercoat layer (D) may be composed of any one of them, or may be composed of a plurality of types. A light-transmitting underlayer containing silicon oxide is preferable, and a light-transmitting underlayer made of silicon oxide is more preferable.

  One layer of the undercoat layer (D) may be disposed. Alternatively, two or more layers may be arranged adjacent to each other or separated from each other via other layers.

  As for the thickness per layer of an undercoat layer (D), 15-40 nm etc. are mentioned. When two or more layers are disposed adjacent to each other, the total thickness of all the undercoat layers (D) adjacent to each other may be within the above range. In the example list shown on the left, the following are more preferable than the above.

  The method of disposing the undercoat layer (D) may be either wet or dry, and is not particularly limited. Examples of the wet include a sol-gel method and a method of applying a fine particle dispersion or colloid solution. It is done. Examples of the method for disposing the undercoat layer (D) include a method of laminating on an adjacent layer by a sputtering method, an ion plating method, a vacuum deposition method, or a pulse laser deposition method.

1.5 Other layers The light-transmitting conductive film of the present invention is provided with the optical adjustment layer (B) and the light-transmitting conductive layer (C) of the light-transmitting support layer (A). On the side surface, at least one layer selected from the group consisting of the undercoat layer (D) and at least one other layer (E) may be further disposed.

  Although it does not specifically limit as another layer (E), For example, an adhesive layer etc. are mentioned.

  The adhesive layer is a layer that is disposed between two layers so as to be adjacent to each other and to adhere the two layers to each other. Although it does not specifically limit as a contact bonding layer, For example, what is normally used as a contact bonding layer in the transparent conductive film for touchscreens can be used.

1.6 Use of light-transmitting conductive film of the present invention The light-transmitting conductive film of the present invention is preferably used for touch panels. The light-transmitting conductive film of the present invention is particularly preferably used for a capacitive touch panel. A light-transmitting conductive film used for manufacturing a resistive touch panel generally requires a surface resistivity (sheet resistance) of about 100 to 1,000 Ω / sq. On the other hand, a light-transmitting conductive film used for manufacturing a capacitive touch panel generally has a lower surface resistivity. The light-transmitting conductive film of the present invention has a reduced resistivity, and is thus preferably used for the production of a capacitive touch panel. The details of the capacitive touch panel are as described in 2.

2. Capacitive touch panel of the electrostatic capacitance type touch panel <br/> invention of the present invention comprises a light transmissive, electrically-conductive film of the present invention, comprise other members according to necessity.

Specific examples of the configuration of the capacitive touch panel according to the present invention include the following configurations. The protective layer (1) side is used so that the operation screen side faces, and the glass (5) side faces the side opposite to the operation screen.
(1) Protective layer (2) Light transmissive conductive film of the present invention (Y-axis direction)
(3) Insulating layer (4) Light transmissive conductive film of the present invention (X-axis direction)
(5) Glass Although the capacitive touch panel of the present invention is not particularly limited, for example, it can be produced by combining the above (1) to (5) and other members as required according to a usual method. it can.

3. Production method of light transmissive conductive film of the present invention The light transmissive conductive film of the present invention can be produced by disposing each layer as described for each layer. For example, the light-transmissive support layer (A) may be sequentially disposed on the surface on which the light-transmissive conductive layer (C) is disposed from the lower layer side, but the arrangement order is not particularly limited. For example, first, another layer may be disposed on one surface of a layer that is not the light-transmissive support layer (A) (for example, the light-transmissive conductive layer (C)). Alternatively, one composite layer is obtained by arranging two or more layers adjacent to each other on the one hand, or at the same time, two or more layers are similarly disposed adjacent to each other on the other side. Thus, one type of composite layer may be obtained, and these two types of composite layers may be further arranged adjacent to each other.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

Example 1
An optical adjustment layer of an acrylate resin containing zirconia particles having an average particle diameter of 16 nm was formed on a PET resin substrate (light-transmitting support layer) having a thickness of 125 μm so as to have a thickness of 0.5 μm.

  In Examples and Comparative Examples, the average particle diameter of zirconia particles was determined by observation with a transmission electron microscope as follows. Specifically, the light transmissive conductive film was covered with a resin, the light transmissive conductive film was thinly cut perpendicularly to the film using a microtome, and the cross section was observed. Thus, the length in the long axis direction of 14 particles obtained by removing the upper 3 particles and the lower 3 particles in the long axis direction length from 20 randomly selected particles that can be visually recognized. The number average value was taken as the average particle size.

At this time, Ra of the optical adjustment layer was 0.7 nm. A SiO ₂ layer of 20 nm was formed on this optical adjustment layer by sputtering, and indium tin oxide (ITO) was formed to a thickness of 23 nm. Specifically, a light transmissive conductive layer is formed by a DC magnetron sputtering method using a sintered body material made of indium oxide: 95 wt% and tin oxide: 5 wt% as a target material, and heated in the atmosphere. The light-transmitting conductive film of the present invention was finally obtained. At this time, after evacuating the inside of the chamber to 5.0 × 10 ⁻⁴ Pa or less, oxygen gas and argon gas are introduced into the chamber so that the oxygen partial pressure becomes 6.5 × 10 ⁻³ Pa. The sputtering treatment was performed at a chamber internal pressure of 0.3 to 0.4 Pa.
Thereafter, heat treatment was performed in the atmosphere at 140 ° C. for 60 minutes to obtain a light-transmitting conductive film of the present invention. This film was evaluated by XRD and AFM.

  In Examples and Comparative Examples, XRD measurement by a thin film method was performed as follows. The X-ray diffractometer was measured by a thin film method using a Rigaku thin film evaluation sample horizontal X-ray diffractometer SmartLab. A parallel beam optical arrangement was used, and a CuKα ray (wavelength: 1.54186Å) was used as a light source at a power of 40 kV and 30 mA. The incident side slit system uses a solar slit of 5.0 °, a height control slit of 10 mm, and an incident slit of 0.1 mm, and the light receiving side slit has a parallel slit analyzer (PSA) of 0.114 deg. Was used. The detector used was a scintillation counter. The sample stage used a porous adsorption sample holder, and the sample was adsorbed and fixed by a pump. The incident side was fixed at 0.50 °, the step interval was 0.01 °, the measurement speed was 3.0 ° / min, and the measurement range was 10 ° to 60 °.

  As a result of evaluation by XRD, the ratio of the peak around 2θ = 28 ° derived from zirconia to the peak of (222) plane derived from indium oxide was 0.15.

  In Examples and Comparative Examples, the average particle size of indium tin oxide was measured as follows. A scanning probe microscope (Shimadzu Corporation, SPM-9700) was used to probe a 0.5 μm square measurement surface in a predetermined contact mode (OMLY TRUS-PSA-1 spring constant 0.15 N made by OLYMPUS) / M) from an image obtained by scanning. Specifically, for the indium tin oxide particles of 1 nm to 30 nm from the observed image, the particle diameter is classified every 1 nm, the number of particles integrated in each particle diameter is examined, and the particle diameter of D50 in the particle size distribution is averaged. Particle size was used.

  The average particle size of indium tin oxide was 6.2 nm.

Example 2
An optical adjustment layer of an acrylate resin containing zirconia particles having an average particle diameter of 25 nm was formed to a thickness of 1.0 μm. Other than that was carried out similarly to Example 1, and obtained the transparent electroconductive film of this invention. As a result of evaluation by XRD, the ratio of the peak around 2θ = 28 ° derived from zirconia to the peak of (222) plane derived from indium oxide was 0.30. The average particle diameter of indium tin oxide was 5.7 nm.

Example 3
An optical adjustment layer of an acrylate resin containing zirconia particles having an average particle diameter of 25 nm was formed to a thickness of 2.0 μm. Other than that was carried out similarly to Example 1, and obtained the transparent electroconductive film of this invention. As a result of evaluation by XRD, the ratio of the peak near 2θ = 28 ° derived from zirconia to the peak of the (222) plane derived from indium oxide was 0.65. The average particle diameter of indium tin oxide was 3.6 nm.

Example 4
An optical adjustment layer of an acrylate resin containing zirconia particles having an average particle diameter of 25 nm was formed to a thickness of 2.9 μm. Other than that was carried out similarly to Example 1, and obtained the transparent electroconductive film of this invention. As a result of evaluation by XRD, the ratio of the peak near 2θ = 28 ° derived from zirconia to the peak of the (222) plane derived from indium oxide was 0.94. The average particle diameter of indium tin oxide was 4.2 nm.

Example 5
An optical adjustment layer of acrylate resin containing zirconia particles having an average particle diameter of 34 nm was formed to a thickness of 1.0 μm. At this time, Ra of the optical adjustment layer was 1.8 nm. Other than that was carried out similarly to Example 1, and obtained the transparent electroconductive film of this invention. As a result of evaluation by XRD, the ratio of the peak near 2θ = 28 ° derived from zirconia to the peak of the (222) plane derived from indium oxide was 0.32. The average particle diameter of indium tin oxide was 7.7 nm.

Comparative Example 1
An optical adjustment layer of an acrylate resin containing zirconia particles having an average particle diameter of 16 nm was formed to a thickness of 0.2 μm. Other than that was carried out similarly to Example 1, and obtained the transparent electroconductive film. As a result of evaluation by XRD, no peak derived from zirconia was detected. The average particle diameter of indium tin oxide was 6.8 nm.

Comparative Example 2
An optical adjustment layer of an acrylate resin containing zirconia particles having an average particle diameter of 16 nm was formed to a thickness of 5.0 μm. Other than that was carried out similarly to Example 1, and obtained the transparent electroconductive film. As a result of evaluation by XRD, the ratio of the peak around 2θ = 28 ° derived from zirconia to the peak of (222) plane derived from indium oxide was 1.5. The average particle diameter of indium tin oxide was 4.9 nm.

Comparative Example 3
An optical adjustment layer of acrylate resin containing zirconia particles having an average particle diameter of 45 nm was formed to a thickness of 2.8 μm. At this time, Ra of the optical adjustment layer was 2.5 nm. Other than that was carried out similarly to Example 1, and obtained the transparent electroconductive film. As a result of evaluation by XRD, the ratio of the peak around 2θ = 28 ° derived from zirconia to the peak of (222) plane derived from indium oxide was 1.5. The average particle diameter of indium tin oxide was 8.4 nm.

  About the light-transmitting conductive film of Examples 1-5 obtained as mentioned above and Comparative Examples 1-3, index matching (IM) and etching property were evaluated as follows.

Evaluation of index matching was performed as follows. In order to form a comb pattern (2 mm width, 10 mm length) in the width direction in the vicinity of the center of the light-transmitting conductive film cut to a width of 5 cm and a length of 10 cm, the following operation was performed.
One of four sides of a silicon rubber plate having a width of 5 cm and a length of 5 cm was cut into a comb pattern. The silicon rubber plate is light-transmitting conductive so that the comb-shaped pattern is placed near the center of the light-transmitting conductive film on the ITO side of the light-transmitting conductive film cut to 5 cm wide × 10 cm long Laminated to film. An etching resist was applied to the silicon rubber side of the light-transmitting conductive film bonded with silicon rubber, dried at 80 ° C. for 30 minutes, and then the silicon rubber plate was peeled off. As a result, a light-transmitting conductive film in which the ITO surface and the etching resist surface were exposed with the comb pattern as a boundary was obtained. This was immersed in 20% hydrochloric acid for 20 minutes to dissolve ITO. Then, it was ultrasonically treated for 10 minutes while being immersed in a 0.5 M KOH solution, and washed with water to obtain a comb pattern film of ITO.
A comb pattern film was placed on white paper and black paper, and the visibility at the edge of the ITO pattern was confirmed.
Evaluation was performed as follows. When the pattern of ITO can hardly be confirmed on white paper and black paper, “◎”, the pattern of ITO can hardly be confirmed on white paper and black paper, but the pattern can be confirmed by changing the observation angle in any sample “◯” indicates a certain case, “Δ” indicates that the pattern can be confirmed in any sample by changing the observation angle, and “X” indicates that the pattern can be confirmed in both samples.

The etching property was evaluated as follows.
The light transmissive conductive film was immersed in 20% hydrochloric acid, and the time until the surface resistance could not be measured was determined. For the light-transmitting conductive film, the immersion time was set at intervals of 10 seconds from 10 seconds to 90 seconds.
When the etching processing completion time is 40 seconds and 50 seconds, “◎”, when 30 seconds, 60 seconds, and 70 seconds, “◯”, when 20 seconds and 80 seconds, “△”, 10 seconds, 90 seconds, and More than that was evaluated as “x”. If the etching process time is too short, or conversely too long, it is difficult to control the etching process, which is not preferable.

  Evaluation of chemical resistance was performed as follows. The light-transmitting conductive film was immersed in 1% hydrochloric acid for 30 minutes and washed with water. The ratio R / R0 of the surface resistance value R at this time and the surface resistance value R0 before being immersed in hydrochloric acid was determined. At this time, when R / R0 is less than 1.1, “◎”, when R / R0 is 1.1 or more and less than 1.2, “◯”, R / R0 is 1.2 or more and 1.3. When it was less than “Δ”, it was judged as “X” when R / R0 was 1.3 or more.

  The evaluation results are shown in Table 1. In Table 1, the ratio of the peak around 2θ = 28 ° derived from zirconia to the peak of the (222) plane derived from indium oxide is simply referred to as “peak ratio”.

1 Light-transmissive conductive film 11 Light-transmissive support layer (A)
12 Optical adjustment layer (B)
13 Light transmissive conductive layer (C)
14 Undercoat layer (D)

Claims (6)

(A) a light transmissive support layer;
(B) an optical adjustment layer; and (C) a light-transmitting conductive layer containing indium tin oxide,
The optical adjustment layer (B) is disposed on at least one surface of the light transmissive support layer (A) directly or via one or more other layers, and the light transmissive conductive layer (C ) Is a light transmissive conductive film disposed on at least one surface of the light transmissive support layer (A) via at least the optical adjustment layer (B):
The optical adjustment layer (B) contains zirconia and has a thickness of 0.4 to 3 μm; and in the XRD measurement by a thin film method, indium tin oxide having a peak around 2θ = 28 ° derived from zirconia A ratio of the derived (222) plane to the peak is 0.1 to 1.0, and the light transmissive conductive film. 2. The light transmissive property according to claim 1, wherein an average surface roughness Ra of the surface of the optical adjustment layer (B) opposite to the light transmissive support layer (A) is 0.4 to 2.0 nm. Conductive film. The light-transmitting conductive film according to claim 1 or 2, wherein the zirconia has an average particle diameter of 10 to 40 nm. The light-transmitting conductive film according to any one of claims 1 to 3, wherein an average particle diameter of the indium tin oxide is 3.0 to 8.0 nm. The light according to any one of claims 1 to 4, wherein the light-transmissive conductive layer (C) can be obtained by heating a layer containing indium tin oxide at 90 to 160 ° C in the atmosphere for 10 to 120 minutes. Transparent conductive film. A touch panel containing the light transmissive conductive film according to claim 1.

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