JP2017091858A - Amorphous transparent conductive film, crystalline transparent conductive film and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an amorphous transparent conductive film, a crystalline transparent conductive film and a manufacturing method thereof, capable of improving a surface resistance value, optical characteristics and productivity.SOLUTION: An amorphous transparent conductive film 1 includes a transparent base material 2 and an amorphous transparent conductive layer 5 sequentially in a thickness direction. The amorphous transparent conductive layer 5 includes an amorphous indium-tin complex oxide. The amorphous transparent conductive layer 5 is 30-40 nm thick. The amorphous transparent conductive layer 5 has a specific resistance of 6.0×10Ω cm to 8.0×10Ω cm. The amorphous transparent conductive layer 5 has a Hall mobility of 15.0 cm/Vs to 30.0 cm/V s.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an amorphous transparent conductive film, a crystalline transparent conductive film and a method for producing the same, and more specifically, an amorphous transparent conductive film used for a film for a touch panel, a crystalline transparent conductive film, And it is related with the manufacturing method of a crystalline transparent conductive film.

  Conventionally, it is known that an image display device includes a film for a touch panel on which a transparent wiring layer made of indium-tin composite oxide (ITO) is formed. A touch panel film is generally produced by patterning an ITO layer into a wiring pattern in a transparent conductive film in which an ITO layer is laminated on a transparent substrate. And in this film for touch panels, in order to reduce the surface resistance value, it is known to crystallize (convert) an ITO layer by heating etc. (for example, refer to patent documents 1).

  In Patent Document 1, a target having a Sn atomic weight of more than 6 wt% and 15 wt% or less is used on a transparent substrate, and the substrate temperature is more than 100 ° C. in an atmosphere where the partial pressure of water is 0.1% or less. A manufacturing method is disclosed in which an amorphous transparent conductive layer made of ITO is formed by sputtering film formation at a temperature of ℃ or less, and then the amorphous transparent conductive layer is heated to be converted into a crystalline transparent conductive layer. ing.

  The crystalline transparent conductive layer thus obtained has a good surface resistance value.

JP 2012-134085 A

  However, in recent years, with an increase in the size of the image display device, further improvement of the surface resistance value, that is, further reduction of the surface resistance value has been demanded.

  By the way, in order to reduce the surface resistance value, there is a method of increasing the thickness of the transparent conductive layer made of ITO. However, when the transparent conductive layer is thickened, there is a problem that optical characteristics such as transparency are reduced.

  It is also desired to improve productivity by reducing the time for crystallization of amorphous ITO.

  An object of the present invention is to provide an amorphous transparent conductive film capable of improving surface resistance, optical characteristics, and productivity, a crystalline transparent conductive film, and a method for producing the same.

The present invention
[1] A transparent substrate and an amorphous transparent conductive layer are sequentially provided in the thickness direction, and the amorphous transparent conductive layer is made of an amorphous indium-tin composite oxide, and the amorphous transparent conductive layer The thickness of the layer is 30 nm or more and 40 nm or less, and the specific resistance of the amorphous transparent conductive layer is 6.0 × 10 ⁻⁴ Ω · cm or more and 8.0 × 10 ⁻⁴ Ω · cm or less, The amorphous transparent conductive film, wherein the hole mobility of the amorphous transparent conductive layer is 15.0 cm ² / V · s or more and 30.0 cm ² / V · s or less,
[2] The amorphous transparent conductive film according to [1], further comprising an optical adjustment layer disposed between the transparent substrate and the amorphous transparent conductive layer,
[3] The amorphous transparent conductive film according to [2], further comprising a hard coat layer disposed between the transparent substrate and the optical adjustment layer,
[4] A crystalline material formed by heating the amorphous transparent conductive film according to any one of [1] to [3], and comprising the transparent substrate and a crystalline indium-tin composite oxide. A crystalline transparent conductive film comprising a transparent conductive layer in order in the thickness direction,
[5] The crystalline transparent conductive material according to [4], wherein a specific resistance of the crystalline transparent conductive layer is 1.8 × 10 ⁻⁴ Ω · cm or more and 2.3 × 10 ⁻⁴ Ω · cm or less. the film,
[6] The difference between the transmittance of the crystalline transparent conductive film for light having a wavelength of 450 nm and the transmittance of the transparent substrate for light having a wavelength of 450 nm is 7.0% or less. 5], a crystalline transparent conductive film,
[7] A step of preparing an amorphous transparent conductive film comprising a transparent substrate and an amorphous transparent conductive layer made of amorphous indium-tin composite oxide in order in the thickness direction, and the amorphous Converting the amorphous indium tin composite oxide to crystalline indium tin composite oxide by heating the transparent transparent conductive film, wherein the amorphous transparent conductive layer has a thickness of 30 nm or more and 40 nm or less, and the specific resistance of the amorphous transparent conductive layer is 6.0 × 10 ⁻⁴ Ω · cm or more and 8.0 × 10 ⁻⁴ Ω · cm or less. The manufacturing method of the crystalline transparent conductive film whose hole mobility of a conductive layer is 15.0 cm < ² > / V * s or more and 30.0 cm < ² > / V * s or less is included.

  According to the amorphous transparent conductive film of the present invention and the method for producing a crystalline transparent conductive film using the same, a crystalline transparent conductive film having good surface resistance and optical properties is produced with high productivity. be able to.

  According to the crystalline transparent conductive film of the present invention, the surface resistance value and the optical characteristics are good.

FIG. 1 shows a side sectional view of an embodiment of the amorphous transparent conductive film of the present invention. FIG. 2 is a side sectional view of a crystalline transparent conductive film obtained by crystallizing the amorphous transparent conductive film of FIG. FIG. 3 shows a side sectional view of another embodiment (embodiment in which an amorphous ITO layer is laminated on one side) of the amorphous transparent conductive film of the present invention. FIG. 4 is a side sectional view of a crystalline transparent conductive film obtained by crystallizing the amorphous transparent conductive film of FIG. FIG. 5 shows a side sectional view of another embodiment (embodiment in which an amorphous ITO layer is directly laminated on the upper surface of a transparent substrate) of the amorphous transparent conductive film of the present invention. FIG. 6 is a side sectional view of a crystalline transparent conductive film obtained by crystallizing the amorphous transparent conductive film of FIG.

  In FIG. 1, the vertical direction of the paper is the vertical direction (thickness direction, first direction), the upper side of the paper is the upper side (one side in the thickness direction, the first direction), and the lower side of the paper is the lower side (thickness direction). The other side, the other side in the first direction). 2 to 6 also conform to FIG.

1. Amorphous transparent conductive film The amorphous transparent conductive film 1 has a film shape (including a sheet shape) having a predetermined thickness, extends in a predetermined direction (plane direction) orthogonal to the thickness direction, and is flat. It has an upper surface and a flat lower surface. The amorphous transparent conductive film 1 is, for example, one part such as a base material for a touch panel provided in the image display device, that is, not an image display device. In other words, the amorphous transparent conductive film 1 is a part for producing an image display device and the like, and does not include an image display element such as an LCD module, and is a device that can be distributed industrially and used industrially. .

  Specifically, as shown in FIG. 1, the amorphous transparent conductive film 1 includes, for example, a transparent substrate 2, a hard coat layer 3, an optical adjustment layer 4, and an amorphous transparent conductive layer 5. Are provided in order in the thickness direction. That is, the amorphous transparent conductive film 1 includes the transparent substrate 2, the first hard coat layer 3 </ b> A disposed on the upper surface of the transparent substrate 2, and the first optical disposed on the upper surface of the first hard coat layer 3 </ b> A. The adjustment layer 4A, the first amorphous transparent conductive layer 5A disposed on the upper surface of the first optical adjustment layer 4A, the second hard coat layer 3B disposed on the lower surface of the transparent substrate 2, and the second hard coat A second optical adjustment layer 4B disposed on the lower surface of the layer 3B; and a second amorphous transparent conductive layer 5B disposed on the lower surface of the second optical adjustment layer 4B. The amorphous transparent conductive film 1 is preferably made of a transparent substrate 2, a hard coat layer 3 (first hard coat layer 3A and second hard coat layer 3B), and an optical adjustment layer 4 (first optical adjustment layer). 4A and the second optical adjustment layer 4B) and the amorphous transparent conductive layer 5 (the first amorphous transparent conductive layer 5A and the second amorphous transparent conductive layer 5B). Hereinafter, each layer will be described in detail.

1-1. Transparent substrate The transparent substrate 2 is a substrate that ensures the mechanical strength of the amorphous transparent conductive film 1. The transparent substrate 2 supports the amorphous transparent conductive layer 5 together with the hard coat layer 3 and the optical adjustment layer 4.

  The transparent substrate 2 is a polymer film having transparency, for example. Examples of the material of the polymer film include polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate, for example, (meth) acrylic resins (acrylic resin and / or methacrylic resin) such as polymethacrylate, Olefin resins such as polyethylene, polypropylene, cycloolefin polymer (COP), for example, polycarbonate resin, polyether sulfone resin, polyarylate resin, melamine resin, polyamide resin, polyimide resin, cellulose resin, polystyrene resin, norbornene resin, etc. It is done. The polymer film can be used alone or in combination of two or more. From the viewpoints of transparency, heat resistance, mechanical strength, etc., polyester resins and olefin resins are preferable, and PET and COP are more preferable.

  The transmittance T1 of the transparent substrate 2 with respect to light having a wavelength of 450 nm is, for example, 80% or more, preferably 85% or more, and, for example, 100% or less. The transmittance can be measured using a high-speed integrating sphere spectral transmittance meter (“DOT-3”, manufactured by Murakami Color Research Laboratory Co., Ltd.).

  The thickness of the transparent substrate 2 is, for example, 2 μm or more, preferably 20 μm or more, for example, 300 μm or less, preferably, from the viewpoint of mechanical strength, scratch resistance, hitting characteristics in the touch panel film, 150 μm or less. The thickness of the transparent substrate 2 can be measured using, for example, a micro gauge thickness gauge.

  In addition, the easily bonding layer, the adhesive bond layer, the separator, etc. may be provided in the upper surface and / or lower surface of the transparent base material 2 as needed.

1-2. First Hard Coat Layer The first hard coat layer 3A is formed on both surfaces of the amorphous transparent conductive film 1 (ie, the first amorphous transparent conductive film) when a plurality of amorphous transparent conductive films 1 are laminated. The upper surface of the layer 5A and the lower surface of the second amorphous transparent conductive layer 5B (in the case of the crystalline transparent conductive film 6 after crystallization, the upper surface of the first crystalline transparent conductive layer 7A and the second crystalline transparent conductive layer This is a scratch protective layer (anti-blocking layer) for preventing scratches on the lower surface of the layer 7B, and the first hard coat layer 3A is an amorphous transparent conductive layer 5 (crystalline transparent after crystallization). After the conductive layer 7) is etched into the wiring pattern, it will be described later so that the difference between the pattern portion and the non-pattern portion where the pattern portion is not formed is not recognized (that is, the visual recognition of the wiring pattern is suppressed). Optical adjustment Together with the layer 4, there may be a refractive index adjusting layer that adjusts the refractive index of the amorphous transparent conductive film 1 (crystalline transparent conductive film 6 after crystallization).

  The first hard coat layer 3 </ b> A has a film shape (including a sheet shape). For example, the first hard coat layer 3 </ b> A is disposed on the entire upper surface of the transparent substrate 2 so as to be in contact with the upper surface of the transparent substrate 2. More specifically, the first hard coat layer 3A is in contact with the upper surface of the transparent substrate 2 and the lower surface of the first optical adjustment layer 4A between the transparent substrate 2 and the first optical adjustment layer 4A. Have been placed.

  The first hard coat layer 3A is a resin layer formed from, for example, a resin composition for a hard coat layer.

  The resin composition for hard coat layers contains, for example, a resin. The resin composition for a hard coat layer preferably contains a resin and particles, and more preferably consists of a resin and particles.

  Examples of the resin include a curable resin and a thermoplastic resin (for example, a polyolefin resin), and a curable resin is preferable.

  Examples of the curable resin include an active energy ray-curable resin that is cured by irradiation with active energy rays (specifically, ultraviolet rays, electron beams, etc.), for example, a thermosetting resin that is cured by heating, and the like. Preferably, an active energy ray curable resin is used.

  Examples of the active energy ray-curable resin include a polymer having a functional group having a polymerizable carbon-carbon double bond in the molecule. Examples of such a functional group include a vinyl group and a (meth) acryloyl group (methacryloyl group and / or acryloyl group).

  Examples of the active energy ray curable resin include (meth) acrylic ultraviolet curable resins such as urethane acrylate and epoxy acrylate.

  Examples of the curable resin other than the active energy ray curable resin include urethane resin, melamine resin, alkyd resin, siloxane polymer, and organic silane condensate.

  The resins can be used alone or in combination of two or more.

  Examples of the particles include inorganic particles and organic particles. Examples of the inorganic particles include silica particles, for example, metal oxide particles composed of zirconium oxide, titanium oxide, zinc oxide, tin oxide, and the like, for example, carbonate particles such as calcium carbonate. Examples of the organic particles include crosslinked acrylic resin particles. The particles can be used alone or in combination of two or more.

  The particles are preferably organic particles, more preferably crosslinked acrylic resin particles.

  From the viewpoint of scratch resistance and transparency, the mode particle diameter of the particles is, for example, 0.8 μm or more, preferably 1.0 μm or more, and for example, 20 μm or less, preferably 10 μm or less. In the present specification, the mode particle diameter refers to a particle diameter showing the maximum value of the particle distribution. For example, a flow particle image analyzer (manufactured by Sysmex, product name “FPTA-3000S”) is used. It is calculated | required by measuring on conditions (Sheath liquid: Ethyl acetate, Measurement mode: HPF measurement, Measurement method: Total count). As the measurement sample, particles obtained by diluting the particles to 1.0% by weight with ethyl acetate and uniformly dispersing them using an ultrasonic cleaner are used.

  The content ratio of the particles is, for example, 0.01 parts by mass or more, preferably 0.1 parts by mass or more, and for example, 10 parts by mass or less, preferably 5 parts by mass with respect to 100 parts by mass of the resin. It is as follows.

  The thickness of the first hard coat layer 3A is, for example, 200 nm or more, preferably 800 nm or more, and, for example, 10 μm or less, preferably 5 μm or less from the viewpoint of scratch resistance and suppression of visual recognition of the wiring pattern. .

  The thickness of the first hard coat layer 3A can be calculated based on, for example, the wavelength of the interference spectrum observed using the instantaneous multi-photometry system.

1-3. First Optical Adjustment Layer The first optical adjustment layer 4A, together with the first hard coat layer 3A, suppresses the visual recognition of the wiring pattern in the amorphous transparent conductive layer 5 (the crystalline transparent conductive layer 7 after crystallization). In order to ensure excellent transparency in the amorphous transparent conductive film 1, the optical properties (for example, refractive index) of the amorphous transparent conductive film 1 (the crystalline transparent conductive film 6 after crystallization) are obtained. ).

  The first optical adjustment layer 4A has a film shape (including a sheet shape). For example, the first optical adjustment layer 4A is disposed on the entire upper surface of the first hard coat layer 3A so as to be in contact with the upper surface of the first hard coat layer 3A. Has been. More specifically, the first optical adjustment layer 4A includes the upper surface of the first hard coat layer 3A and the first amorphous transparent conductive layer between the first hard coat layer 3A and the amorphous transparent conductive layer 5. It arrange | positions so that the lower surface of 5A may be contacted.

  4A of 1st optical adjustment layers are resin layers formed from the resin composition for optical adjustment layers.

  The resin composition for optical adjustment layers contains resin, for example. The resin composition for an optical adjustment layer preferably contains a resin and particles, and more preferably consists of a resin and particles.

  Although it does not specifically limit as resin, The same thing as resin used with the resin composition for hard-coat layers is mentioned. The resins can be used alone or in combination of two or more. Preferably, a curable resin, more preferably an active energy ray curable resin is used.

  The resin content is, for example, 10% by mass or more, preferably 25% by mass or more, and, for example, 95% by mass or less, preferably 60% by mass or less, with respect to the resin composition for an optical adjustment layer. It is.

As the particles, a suitable material can be selected according to the refractive index required by the first optical adjustment layer 4A, and examples thereof include the same particles as those used in the resin composition for hard coat layers. The particles can be used alone or in combination of two or more. Preferred are inorganic particles, more preferred are metal oxide particles, and still more preferred are zirconium oxide particles (ZnO ₂ ).

  The average particle diameter (median diameter) of the particles is, for example, 1 nm or more, preferably 5 nm or more, and for example, 500 nm or less, preferably 100 nm or less.

  The content ratio of the particles is, for example, 5% by mass or more, preferably 40% by mass or more, and, for example, 90% by mass or less, preferably 75% by mass or less, with respect to the resin composition for an optical adjustment layer. It is.

  The refractive index of the first optical adjustment layer 4A is, for example, 1.50 or more, preferably 1.60 or more, and for example, 1.80 or less, preferably 1.75 or less. In the present invention, the refractive index is measured by an Abbe refractometer.

  The thickness of the first optical adjustment layer 4A is, for example, 50 nm or more, preferably 80 nm or more, and, for example, 300 nm or less, preferably 150 nm or less, from the viewpoint of suppressing visual recognition of the wiring pattern and low resistance.

  The thickness of the first optical adjustment layer 4A can be calculated based on, for example, the wavelength of the interference spectrum observed using the instantaneous multi-photometry system.

1-4. First Amorphous Transparent Conductive Layer The first amorphous transparent conductive layer 5A is a conductive layer for forming a pattern portion (circuit) by forming it in a wiring pattern in a subsequent process.

  As shown in FIG. 1, the first amorphous transparent conductive layer 5A is the uppermost layer of the amorphous transparent conductive film 1 and has a film shape (including a sheet shape). The entire upper surface of the adjustment layer 4A is disposed so as to contact the upper surface of the first optical adjustment layer 4A.

  The first amorphous transparent conductive layer 5A is an ITO layer made of amorphous (amorphous) indium tin composite oxide (ITO).

The tin oxide (SnO ₂ ) content is, for example, 0.5% by mass or more, preferably 3% by mass or more with respect to the total amount of tin oxide and indium oxide (In ₂ O ₃ ). , 15% by mass or less, preferably 13% by mass or less. By setting the content of tin oxide to the above lower limit or more, the durability of the ITO layer can be further improved. By making the content of tin oxide below the above upper limit, crystallization of the ITO layer can be facilitated, and the stability of transparency and specific resistance can be improved.

  The first amorphous transparent conductive layer 5A may be formed of a single ITO layer, or may be formed of a multilayer ITO layer.

  When the first amorphous transparent conductive layer 5A is formed of a multilayer ITO layer, the number of layers is preferably two.

  When the first amorphous transparent conductive layer 5A is formed of two layers, the content of tin oxide in the lower layer (layer in contact with the optical adjustment layer 4) is preferably the upper layer (on the side exposed to the surface) More than the tin oxide content of the layer). Thereby, it is possible to improve the surface resistance value of the first crystalline transparent conductive layer 7A while improving the crystallization speed of the first amorphous transparent conductive layer 5A.

“ITO” in this specification may be a composite oxide containing at least indium (In) and tin (Sn), and may contain additional components other than these. Examples of the additional component include metal elements other than In and Sn. Specifically, Zn, Ga, Sb, T
i, Si, Zr, Mg, Al, Au, Ag, Cu, Pd, W, Fe, Pb, Ni, Nb,
Cr, Ga, etc. are mentioned.

  The total thickness of the first amorphous transparent conductive layer 5A is not less than 30 nm and not more than 40 nm. Preferably, it is 30 nm or more and 35 nm or less. By setting the thickness of the first amorphous transparent conductive layer 5A to the above lower limit or more, the surface resistance value of the first crystalline transparent conductive layer 7A after crystallization is excellent. On the other hand, by setting the thickness of the first amorphous transparent conductive layer 5A to the upper limit or less, it is possible to suppress cracks and the like generated in the first crystalline transparent conductive layer 7A after crystallization, and the crystalline transparent conductive layer The reliability of the conductive film 6 can be improved.

  The thickness of the first amorphous transparent conductive layer 5A can be measured using, for example, a fluorescent X-ray analyzer.

The specific resistance of the first amorphous transparent conductive layer 5 </ b> A is 6.0 × 10 ⁻⁴ Ω · cm or more and 8.0 × 10 ⁻⁴ Ω · cm or less. Preferably, it is 6.2 × 10 ⁻⁴ Ω · cm or more, more preferably 6.3 × 10 ⁻⁴ Ω · cm or more, and preferably 7.0 × 10 ⁻⁴ Ω · cm or less, More preferably, it is 6.8 × 10 ⁻⁴ Ω · cm or less. By setting the specific resistance of the first amorphous transparent conductive layer 5A within the above range, the crystallization speed is improved, and the crystalline transparent conductive film 6 can be manufactured with high productivity. Further, the surface resistance value and transmittance of the first crystalline transparent conductive layer 7A after crystallization are excellent.

  The specific resistance can be calculated, for example, from the total thickness and surface resistance value of the first amorphous transparent conductive layer 5A.

  The surface resistance value of the first amorphous transparent conductive layer 5A is, for example, 150Ω / □ or more, preferably 180Ω / □ or more, more preferably 200Ω / □ or more, and for example, 300Ω / □ or less, Preferably, it is 250 Ω / □ or less, more preferably 220 Ω / □ or less.

  The surface resistance value can be measured using, for example, a four-terminal method.

The hole mobility of the first amorphous transparent conductive layer 5A is not less than 15.0 cm ² / V · s and not more than 30.0 cm ² / V · s. Preferably, 18.0cm ² / V · s or higher, more preferably at 21.0cm ² / V · s or more, and preferably, 27.0cm ² / V · s or less, more preferably 25. 0 cm ² / V · s or less. By setting the hole mobility of the first amorphous transparent conductive layer 5A within the above range, the crystallization speed is improved, and the crystalline transparent conductive film 6 can be produced with high productivity. Further, the surface resistance value and transmittance of the first crystalline transparent conductive layer 7A after crystallization are excellent.

The carrier density of the first amorphous transparent conductive layer 5A is, for example, 30.0 × 10 ¹⁹ / cm ³ or more, preferably 40.0 × 10 ¹⁹ / cm ³ or more, and for example, 50.0 × 10 ¹⁹ / cm ³ or less, preferably 45.0 × 10 ¹⁹ / cm ³ or less.

  Hall mobility and carrier density can be measured by, for example, a Hall effect measurement system.

  The ITO layer that is the amorphous transparent conductive layer 5 is amorphous, for example, by immersing the ITO layer in 20 ° C. hydrochloric acid (concentration 5% by mass) for 15 minutes, washing with water and drying, 15 mm This can be determined by measuring the resistance between terminals. In this specification, the ITO layer is amorphous when the resistance between terminals of 15 mm of the ITO layer exceeds 2 MΩ after immersion, washing and drying in hydrochloric acid (20 ° C., concentration: 5 mass%). Shall.

1-5. Second Hard Coat Layer The second hard coat layer 3 </ b> B is disposed on the entire lower surface of the transparent substrate 2 so as to be in contact with the lower surface of the transparent substrate 2. More specifically, the second hard coat layer 3B is in contact with the lower surface of the transparent substrate 2 and the upper surface of the second optical adjustment layer 4B between the transparent substrate 2 and the second optical adjustment layer 4B. Have been placed.

  The second hard coat layer 3B is the same layer as the first hard coat layer 3A, and examples thereof include the same ones as described above for the first hard coat layer 3A. That is, the material, configuration, and the like of the second hard coat layer 3B are the same as, for example, the material, configuration, and the like described above for the first hard coat layer 3A.

1-6. Second Optical Adjustment Layer The second optical adjustment layer 4B is disposed on the entire lower surface of the second hard coat layer 3B so as to be in contact with the lower surface of the second hard coat layer 3B. More specifically, the second optical adjustment layer 4B includes a lower surface of the second hard coat layer 3B and a second amorphous transparent layer between the second hard coat layer 3B and the second amorphous transparent conductive layer 5B. It arrange | positions so that the upper surface of the conductive layer 5B may be contacted.

  The second optical adjustment layer 4B is the same layer as the first optical adjustment layer 4A, and examples thereof include the same ones as described above for the first optical adjustment layer 4A. That is, the material, configuration, and the like of the second optical adjustment layer 4B are the same as the material, configuration, and the like described above for the first optical adjustment layer 4A, for example.

1-7. Second Amorphous Transparent Conductive Layer The second amorphous transparent conductive layer 5B is a conductive layer for forming a pattern portion (circuit) by forming it in a wiring pattern in a subsequent process.

  As shown in FIG. 1, the second amorphous transparent conductive layer 5B is the lowermost layer of the amorphous transparent conductive film 1 and has a film shape (including a sheet shape). It arrange | positions so that it may contact the lower surface of the transparent base material 2 in the whole lower surface of this.

  The second amorphous transparent conductive layer 5B is the same layer as the first amorphous transparent conductive layer 5A, that is, an ITO layer made of amorphous (amorphous) indium tin composite oxide (ITO). . The material, configuration, and the like of the second amorphous transparent conductive layer 5B are the same as those described above for the first amorphous transparent conductive layer 5A, for example.

2. Method for Producing Amorphous Transparent Conductive Film A method for producing (preparing) the amorphous transparent conductive film 1 will be described.

  In order to manufacture the amorphous transparent conductive film 1, for example, the hard coat layer 3, the optical adjustment layer 4, and the amorphous transparent conductive layer 5 are sequentially provided on both surfaces of the transparent substrate 2. That is, the first hard coat layer 3A is provided on the upper surface of the transparent substrate 2, the second hard coat layer 3B is provided on the lower surface thereof, and then the first optical adjustment layer 4A and the second hard coat are provided on the upper surface of the first hard coat layer 3A. The second optical adjustment layer 4B is provided on the lower surface of the layer 3B, and then the first amorphous transparent conductive layer 5A is formed on the upper surface of the first optical adjustment layer 4A, and the second amorphous transparent layer is formed on the lower surface of the second optical adjustment layer 4B. A conductive layer 5B is provided. Details will be described below.

  First, a known or commercially available transparent substrate 2 is prepared.

  Then, from the viewpoint of adhesion between the transparent base material 2 and the hard coat layer 3, for example, sputtering, corona discharge, flame, ultraviolet irradiation, electron beam irradiation, chemical conversion, Etching such as oxidation or undercoating can be performed. Moreover, the transparent base material 2 can be dust-removed and cleaned by solvent cleaning, ultrasonic cleaning, or the like.

  Next, hard coat layers 3 are provided on both surfaces of the transparent substrate 2. For example, by wet coating the hard coat layer resin composition on both surfaces of the transparent substrate 2, the first hard coat layer 3 </ b> A on the upper surface of the transparent substrate 2 and the second hard coat layer on the lower surface of the transparent substrate 2. 3B is formed.

  Specifically, for example, a diluted solution obtained by diluting the hard coat layer resin composition with a solvent is prepared, and then the diluted solution is applied to both surfaces of the transparent substrate 2 and the diluted solution is dried.

  Examples of the solvent include an organic solvent and an aqueous solvent (specifically, water), and an organic solvent is preferable. Examples of the organic solvent include alcohol compounds such as methanol, ethanol, and isopropyl alcohol, ketone compounds such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, ester compounds such as ethyl acetate and butyl acetate, and propylene glycol monomethyl ether (PGME). ) And the like, for example, aromatic compounds such as toluene and xylene. Solvents can be used alone or in combination of two or more. Preferably, a ketone compound and an ether compound are used.

  The solid content concentration in the diluted solution is, for example, 1% by mass or more, preferably 10% by mass or more, and for example, 30% by mass or less, preferably 20% by mass or less.

  As a coating method, it can select suitably according to a diluent and a transparent base material. Examples thereof include a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method, and an extrusion coating method.

  A drying temperature is 50 degreeC or more, for example, Preferably, it is 60 degreeC or more, More preferably, it is 70 degreeC or more, for example, 200 degrees C or less, Preferably, it is 150 degrees C or less, More preferably, it is 100 degrees C or less.

  The drying time is, for example, 0.5 minutes or more, preferably 1 minute or more, for example, 60 minutes or less, preferably 20 minutes or less.

  By the application and drying described above, the resin composition for hard coat layer is formed into a film shape on both surfaces of the transparent substrate 2.

  Thereafter, when the resin of the resin composition contains an active energy ray-curable resin, the active energy ray-curable resin is cured by irradiating active energy rays after drying the diluted solution.

  In addition, when a thermosetting resin is contained as the resin of the resin composition for the hard coat layer, the thermosetting resin can be thermoset together with the drying of the solvent by this drying step.

  Next, the optical adjustment layers 4 are provided on both surfaces of the hard coat layer 3 formed on both surfaces of the transparent substrate 2. For example, the first optical adjustment layer is formed on the upper surface of the first hard coat layer 3A by wet-coating the optical adjustment composition on the surface of the hard coat layer 3 (first hard coat layer 3A, second hard coat layer 3B). 4A, the second optical adjustment layer 4B is formed on the lower surface of the second hard coat layer 3B.

  Specifically, a diluted solution obtained by diluting the optical adjustment layer resin composition with a solvent is prepared. Subsequently, the diluted solution is applied to both surfaces of the hard coat layer 3, and the diluted solution is dried.

  Examples of the solvent, the dilution method, the coating method, and the drying method include the same solvents, coating methods, and the like as exemplified with the diluent for the resin composition for hard coat layer.

  When the resin of the resin composition contains an active energy ray curable resin, the active energy ray curable resin is cured by irradiating the active energy ray after drying the diluted solution.

  Next, the amorphous transparent conductive layer 5 is provided on both surfaces of the optical adjustment layer 4. For example, the first amorphous transparent conductive layer 5A is formed on the upper surface of the first optical adjustment layer 4A, and the second amorphous transparent conductive layer 5B is formed on the lower surface of the second optical adjustment layer 4B by a dry method.

  Examples of the dry method include a vacuum deposition method, a sputtering method, and an ion plating method. Preferably, a sputtering method is used.

  In the case of employing the sputtering method, the target material includes ITO. The tin oxide concentration of ITO is, for example, 0.5% by mass or more, preferably 3% by mass or more, more preferably 8% by mass or more, from the viewpoint of durability and crystallization of the ITO layer. For example, it is 15 mass% or less, preferably 13 mass% or less.

  Examples of the sputtering gas include an inert gas such as Ar. Moreover, reactive gas, such as oxygen gas, can be used together as needed. In the case of using the reactive gas in combination, the flow rate ratio of the reactive gas is not particularly limited, but is, for example, 0.1 flow% or more and 5 flow% or less with respect to the total flow ratio of the sputtering gas and the reactive gas. In particular, the flow rate of the reactive gas may be set according to the flow rate ratio of the sputtering gas and the reactive gas, for example, 8 sccm or more, preferably 10 sccm or more, and for example, less than 15 sccm, preferably , 12 sccm or less. By finely adjusting the flow rate of the reaction gas, the desired first amorphous transparent conductive layer 5A can be more suitably formed.

  The discharge atmospheric pressure at the time of sputtering is, for example, 1 Pa or less, preferably 0.1 Pa or more and 0.7 Pa or less, from the viewpoint of suppressing a decrease in sputtering rate, discharge stability, or the like.

The partial pressure of water in the atmosphere during sputtering is, for example, 10 × 10 ⁻⁴ Pa or less, preferably 5 × 10 ⁻⁴ Pa or less. Further, the partial pressure of water is, for example, 1.0% or less, preferably 0.7% or less with respect to the partial pressure of the sputtering gas. Thereby, the growth suppression of the amorphous transparent conductive layer 5 (the first amorphous transparent conductive layer 5A and the second amorphous transparent conductive layer 5B) due to the termination of dangling bonds can be reduced, and the desired non- The crystalline transparent conductive layer 5 can be suitably formed.

  The temperature at the time of sputtering, specifically, the substrate temperature in the transparent substrate 2 is, for example, 100 ° C. or less, preferably 50 ° C. or less, more preferably 30 ° C. or less, and for example, 0 ° C. or more. The temperature is preferably 10 ° C. or higher.

  The base material temperature refers to the surface temperature of a transport base material (transport roll, transport holder, etc.) that contacts the transparent base material 2 during sputtering.

  The power source used for sputtering may be, for example, any of a DC power source, an AC power source, an MF power source, and an RF power source, or a combination thereof.

  Further, in order to form the amorphous transparent conductive layer 5 having a desired thickness and multiple layers, sputtering may be performed a plurality of times by appropriately setting the target material, sputtering conditions, and the like.

  Thereby, the desired amorphous transparent conductive film 1 is obtained.

  If necessary, the amorphous transparent conductive layer 5 may be formed in a stripe pattern or the like by a known etching method.

  Moreover, in the said manufacturing method, the hard-coat layer 3, the optical adjustment layer 4, and the amorphous transparent conductive layer 5 are formed in order in the transparent base material 2, conveying the transparent base material 2 by a roll-to-roll system. Alternatively, some or all of these layers may be formed by a batch method (single-wafer method).

3. Method for Producing Crystalline Transparent Conductive Film A method for producing the crystalline transparent conductive film 6 will be described.

  In order to manufacture the crystalline transparent conductive film 6, a heat treatment is performed on the amorphous transparent conductive layer 5 of the amorphous transparent conductive film 1. Thereby, the amorphous transparent conductive layer 5 (first amorphous transparent conductive layer 5A and second amorphous transparent conductive layer 5B), that is, amorphous ITO is converted into the crystalline transparent conductive layer 7 (first Crystalline transparent conductive layer 7A and second crystalline transparent conductive layer 7B), ie, converted to crystalline ITO.

  Specifically, for example, the amorphous transparent conductive film 1 is heat-treated in the atmosphere.

  The heat treatment can be performed using, for example, an infrared heater or an oven.

  The heating temperature is, for example, 100 ° C. or more, preferably 120 ° C. or more, and for example, 200 ° C. or less, preferably 160 ° C. or less. By setting the heating temperature within the above range, crystallization can be ensured while suppressing thermal damage of the transparent substrate 2 and impurities generated from the transparent substrate 2.

  The heating time is, for example, less than 30 minutes, preferably 20 minutes or less, more preferably 15 minutes or less, and for example, 1 minute or more, preferably 5 minutes or more.

  Thereby, as shown in FIG. 2, the crystalline transparent conductive film 6 provided with the crystalline transparent conductive layer 7 is obtained.

  If the crystalline transparent conductive layer 7 is not formed in the wiring pattern, the amorphous transparent conductive layer 5 is formed in a wiring pattern such as a stripe shape by a known etching method after the heat treatment, if necessary. May be.

4). Crystalline Transparent Conductive Film As shown in FIG. 2, the crystalline transparent conductive film 6 includes, for example, a transparent substrate 2, a hard coat layer 3, an optical adjustment layer 4, and a crystalline transparent conductive layer 7. Prepare in order in the thickness direction. That is, the crystalline transparent conductive film 6 includes the transparent base material 2, the first hard coat layer 3 </ b> A disposed on the top surface of the transparent base material 2, and the first optical adjustment disposed on the top surface of the first hard coat layer 3 </ b> A. Layer 4A, first crystalline transparent conductive layer 7A disposed on the top surface of first optical adjustment layer 4A, second hard coat layer 3B disposed on the bottom surface of transparent substrate 2, and second hard coat layer 3B. A second optical adjustment layer 4B disposed on the lower surface of the second optical adjustment layer 4B, and a second crystalline transparent conductive layer 7B disposed on the lower surface of the second optical adjustment layer 4B. The crystalline transparent conductive film 6 is preferably made of a transparent substrate 2, a hard coat layer 3 (first hard coat layer 3A and second hard coat layer 3B), and an optical adjustment layer 4 (first optical adjustment layer 4A). And the second optical adjustment layer 4B) and the crystalline transparent conductive layer 7 (the first crystalline transparent conductive layer 7A and the second crystalline transparent conductive layer 7B).

  The transparent substrate 2, the hard coat layer 3 and the optical adjustment layer 4 are the same as those described above for the amorphous transparent conductive film 1.

  The first crystalline transparent conductive layer 7A is the uppermost layer of the crystalline transparent conductive film 6 and has a film shape (including a sheet shape). The optical adjustment layer 4 is formed on the entire upper surface of the optical adjustment layer 4. It arrange | positions so that the upper surface of 4 may be contacted.

  The first crystalline transparent conductive layer 7A is an ITO layer made of crystalline indium tin composite oxide (ITO).

The content of tin oxide (SnO ₂ ) is the same as that of the first amorphous transparent conductive layer 5A.

  The thickness of the first crystalline transparent conductive layer 7A is the same as that of the first amorphous transparent conductive layer 5A, and is 30 nm or more and 40 nm or less. Preferably, it is 30 nm or more and 35 nm or less.

The specific resistance of the first crystalline transparent conductive layer 7A is, for example, less than 2.5 × 10 ⁻⁴ Ω · cm, preferably 2.3 × 10 ⁻⁴ Ω · cm or less. It is 0 × 10 ⁻⁴ Ω · cm or more, preferably 1.8 × 10 ⁻⁴ Ω · cm or more. Thereby, the surface resistance value of the crystalline transparent conductive layer 7 is excellent.

  The surface resistance value of the first crystalline transparent conductive layer 7A is, for example, 70Ω / □ or less, preferably 65Ω / □ or less, and for example, 10Ω / □ or more, preferably 30Ω / □ or more.

Hole mobility of the first crystalline transparent conductive layer 7A, for example, 20.0cm ² / V · s or more, or preferably, 24.5cm ² / V · s or more, and is, for example, 35.0cm ² / V · s or less, preferably 30.0 cm ² / V · s or less. Thereby, the surface resistance value of the first crystalline transparent conductive layer 7A is excellent.

The carrier density of the first crystalline transparent conductive layer 7A is, for example, 90 × 10 ¹⁹ / cm ³ or more, preferably 100 × 10 ¹⁹ / cm ³ or more, and for example, 150 × 10 ¹⁹ / cm ³ or less. Preferably, it is 120 × 10 ¹⁹ / cm ³ or less.

  The ITO layer that is the crystalline transparent conductive layer 7 is crystalline. For example, the ITO layer is immersed in hydrochloric acid (concentration: 5% by mass) at 20 ° C. for 15 minutes, washed with water, dried, and dried between about 15 mm. This can be determined by measuring the resistance between terminals. In this specification, when the resistance between terminals between 15 mm is 2 MΩ or less after immersion, washing and drying in hydrochloric acid (20 ° C., concentration: 5 mass%), the ITO layer is assumed to be crystalline.

  As shown in FIG. 1, the second crystalline transparent conductive layer 7B is the lowermost layer of the crystalline transparent conductive film 6 and has a film shape (including a sheet shape). The second optical adjustment layer It arrange | positions so that the lower surface of 4B may contact the lower surface of the 2nd optical adjustment layer 4B.

  The second crystalline transparent conductive layer 7B is the same layer as the first crystalline transparent conductive layer 7A. For example, the second crystalline transparent conductive layer 7B has the same material and configuration as those described above for the first crystalline transparent conductive layer 7A.

  The total light transmittance of the crystalline transparent conductive film 6 is, for example, 80% or more, preferably 85% or more, and, for example, 100% or less. Thereby, optical properties such as transparency are excellent.

  The total light transmittance can be measured according to JIS K 7105 using a haze meter.

  The transmittance T2 of the crystalline transparent conductive film 6 with respect to light having a wavelength of 450 nm is, for example, 78% or more, preferably 80% or more, more preferably 81% or more, and for example, 100% or less. is there.

  The transmittance T2 of the crystalline transparent conductive film 6 is smaller than the transmittance T1 of the transparent substrate 2, and the difference (T1−T2) is, for example, 7.0% or less, preferably 6.0%. Hereinafter, it is more preferably 5.0% or less. Thereby, the visual recognition of a wiring pattern can be suppressed and the visibility as a film for touchscreens becomes favorable.

The amorphous transparent conductive film 1 includes a transparent base material 2, a first hard coat layer 3A, a first optical adjustment layer 4A, and a first amorphous transparent conductive layer 5A made of amorphous ITO. In order in the thickness direction. Further, since the thickness of the first amorphous transparent conductive layer 5A is not less than 30 nm and not more than 40 nm and is relatively thick, the surface resistance value of the first crystalline transparent conductive layer 7A after crystallization becomes good. . In the first amorphous transparent conductive layer 5A, the specific resistance is 6.0 × 10 ⁻⁴ Ω · cm or more and 8.0 × 10 ⁻⁴ Ω · cm or less, and the hole mobility is 15.0 cm ² / V. Since it is set to s or more and 30.0 cm ² / V · s or less, the crystallization speed can be improved. Further, the transparency of the first crystalline transparent conductive layer 7A after crystallization becomes good. These are because the oxygen defects of the first amorphous transparent conductive layer 5A are reduced and the crystallinity is increased by setting the specific resistance and the hole mobility within the above ranges, and Burstein- Although it is presumed that the moss shift is effectively exhibited and the transmittance on the short wavelength side is particularly increased, the present invention is not limited to this inference.

  Moreover, since the crystalline transparent conductive film 6 is obtained by heating the amorphous transparent conductive film 1, the surface resistance value and the optical characteristics are good.

  The amorphous transparent conductive film 1 and the crystalline transparent conductive film 6 are used for a base material for a touch panel provided in an image display device, for example. Examples of the touch panel format include various systems such as an optical system, an ultrasonic system, a capacitive system, and a resistive film system, and the touch panel is particularly preferably used for a capacitive touch panel.

5. In the embodiment shown in FIG. 1, the amorphous transparent conductive film 1 has an amorphous transparent conductive layer 5 (first amorphous transparent conductive layer 5A and second amorphous transparent conductive layer 5B) on both sides thereof. ), An optical adjustment layer 4 (first optical adjustment layer 4A and second optical adjustment layer 4B), and a hard coat layer 3 (first hard coat layer 3A and second hard coat layer 3B). For example, as shown in FIG. 3, the amorphous transparent conductive film 1 can also include the amorphous transparent conductive layer 5, the optical adjustment layer 4, and the hard coat layer 3 only on one side thereof.

  That is, the amorphous transparent conductive film 1 in FIG. 3 includes a transparent substrate 2, a first hard coat layer 3A (hard coat layer 3), a first optical adjustment layer 4A (optical adjustment layer 4), and a first amorphous film. A transparent conductive layer 5A (amorphous transparent conductive layer 5) is sequentially provided in the thickness direction.

  The crystalline transparent conductive film 6 crystallized by heating the amorphous transparent conductive film 1 of FIG. 3 includes, for example, a transparent substrate 2 and a first hard coat layer 3A as shown in FIG. (Hard coat layer 3), first optical adjustment layer 4A (optical adjustment layer 4), and first crystalline transparent conductive layer 7A (crystalline transparent conductive layer 7) are sequentially provided in the thickness direction.

  In the embodiment of FIG. 3, the amorphous transparent conductive film 1 includes a hard coat layer 3, an optical adjustment layer 4, and a second amorphous transparent conductive layer. For example, as shown in FIG. 5, The amorphous transparent conductive film 1 may not include the hard coat layer 3, the optical adjustment layer 4, and the second amorphous transparent conductive layer.

  That is, the amorphous transparent conductive film 1 in FIG. 5 includes a transparent base 2 and a first amorphous transparent conductive layer 5A (amorphous transparent conductive layer 5) in order in the thickness direction. Specifically, the amorphous transparent conductive film 1 in FIG. 5 includes a transparent base material 2 and a first amorphous transparent conductive layer 5 </ b> A disposed directly on the upper surface of the transparent base material 2.

  The crystalline transparent conductive film 6 that is crystallized by heating the amorphous transparent conductive film 1 of FIG. 5 includes, for example, a transparent substrate 2 and a first crystalline transparent conductive film as shown in FIG. A layer 7A (crystalline transparent conductive layer 7) is sequentially provided in the thickness direction.

  4 and 6, the total light transmittance of the crystalline transparent conductive film 6 is, for example, 80% or more, preferably 83% or more, and, for example, 100% or less.

  The transmittance T2 of the crystalline transparent conductive film 6 with respect to light having a wavelength of 450 nm is, for example, 78% or more, preferably 80% or more, and, for example, 100% or less.

  The transmittance T2 of the crystalline transparent conductive film 6 is smaller than the transmittance T1 of the transparent substrate 2, and the difference (T1−T2) is, for example, 7.0% or less, preferably 6.0%. It is as follows.

  Further, for example, although not shown, the amorphous transparent conductive film 1 and the crystalline transparent conductive film 6 obtained therefrom include, in addition to the above, the transparent substrate 2, the amorphous transparent conductive layer 5, and the crystalline Another layer may be interposed between the transparent conductive layer 7.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. In addition, this invention is not limited to an Example and a comparative example at all. In addition, specific numerical values such as a blending ratio (content ratio), physical property values, and parameters used in the following description are described in the above-mentioned “Mode for Carrying Out the Invention”, and a blending ratio corresponding to them ( Substituting the upper limit value (numerical value defined as “less than” or “less than”) or the lower limit value (number defined as “greater than” or “exceeded”) such as content ratio), physical property values, parameters be able to.

Example 1
As the transparent substrate, a cycloolefin polymer (COP) film (manufactured by Zeon Corporation, trade name “Zeonor”, thickness 100 μm) was used.

Next, a plurality of monodisperse particles having a mode particle size of 1.3 μm (manufactured by Soken Chemical Co., Ltd., trade name “SX-130H”) and a binder resin (manufactured by DIC, trade name “Unidic RS29-120)” Ethyl acetate was added to the hard coat layer resin composition to prepare a diluted solution, and the content of the particles was 0.2 parts by mass with respect to 100 parts by mass of the binder resin. The coating solution was dried on both surfaces of the substrate by applying the diluted solution to a thickness of 1.0 μm after drying using a gravure coater and heating at 80 ° C. for 1 minute. A hard coat layer was formed by irradiating ultraviolet light with an integrated light quantity of 250 mJ / cm ^{2 with} a mercury lamp.

Next, on the surfaces of the hard coat layers on both sides, an optical adjustment composition containing 47 parts by mass of an ultraviolet curable resin, 57 parts by mass of zirconia oxide particles (median diameter 40 nm) and PGME (manufactured by JSR, trade name “OPSTAR Z7412”) The solid content was 12 mass%) using a gravure coater, and the coating film was dried by heating at 60 ° C. for 1 minute. Thereafter, an optical adjustment layer having a thickness of 100 nm (0.1 μm) and a refractive index of 1.62 was formed on both surfaces by irradiating an ultraviolet ray with an integrated light amount of 250 mJ / cm ² with a high-pressure mercury lamp and performing a curing treatment. .

Next, in an atmosphere of a mixed gas of argon gas and oxygen of 0.4 Pa, a reactive sputtering method is performed using a sintered body of 10% by mass of tin oxide / 90% by mass of indium oxide as a target. A 25 nm amorphous ITO layer (first layer) was formed on the upper surface of the optical adjustment layer. In film formation, after evacuating the inside of the sputtering apparatus until the partial pressure of water becomes 1.0 × 10 ⁻⁴ Pa or less, argon gas and oxygen gas are introduced so that the oxygen flow rate becomes 10 sccm, Film formation was carried out in an atmosphere with a water pressure of 3.0 × 10 ⁻⁴ Pa at a substrate temperature of 20 ° C. The partial pressure of water at this time was 0.01% with respect to the partial pressure of argon gas.

  Subsequently, sputtering was further performed under the same conditions except that the target was changed to a sintered body of 3% by mass of tin oxide / 97% by mass of indium oxide, and an amorphous ITO layer having a thickness of 7 nm (second layer) Were further laminated. Thereby, the first amorphous transparent conductive layer (thickness 32 nm) was formed on the upper surface of the optical adjustment layer.

  Next, a second amorphous transparent conductive layer (thickness: 32 nm) was laminated on the lower surface of the optical adjustment layer on the lower side of the COP film in the same procedure as described above. That is, a 25 nm ITO layer of 10% by mass of tin oxide / 90% by mass of indium oxide is formed on the lower surface of the COP film, and a 7 nm ITO of 3% by mass of tin oxide / 97% by mass of indium oxide is formed on the lower surface of the ITO layer. Additional layers were formed.

  This obtained the amorphous transparent conductive film of Example 1 (refer FIG. 1).

Example 2
Except for changing the oxygen flow rate to 12 sccm so that the specific resistance and hole density of the amorphous ITO layer (first amorphous transparent conductive layer, second amorphous transparent conductive layer) are as shown in Table 1. Obtained an amorphous transparent conductive film in the same manner as in Example 1 (see FIG. 1).

Example 3
A polyethylene terephthalate (PET) film (trade name “Diafoil”, thickness 50 μm) is used as a transparent substrate, and an amorphous ITO layer (first amorphous transparent conductive film) is formed only on the upper surface of the transparent substrate. Layer) was formed directly. The formation conditions of the amorphous ITO layer were the same as in Example 1 except that the oxygen flow rate was changed to 11 sccm so that the specific resistance and hole density of the amorphous ITO layer were as shown in Table 1. The same was done. This obtained the amorphous transparent conductive film of Example 3 (refer FIG. 5).

Examples 4-5
An amorphous transparent conductive film was obtained in the same manner as in Example 3 except that the configuration, specific resistance, and hole density of the amorphous ITO layer were changed to the values shown in Table 1 (FIG. 5). reference). Specifically, in Example 4, the oxygen flow rate was changed to 11 sccm, and in Example 5, the oxygen flow rate was changed to 12 sccm.

Comparative Examples 1-3
An amorphous transparent conductive film was obtained in the same manner as in Example 1 except that the thickness, specific resistance and hole density of the transparent substrate, amorphous ITO layer were changed to the materials or values shown in Table 1. (See FIG. 1). Specifically, in Comparative Example 1, the oxygen flow rate was changed to 5 sccm, in Comparative Example 2, the oxygen flow rate was changed to 3 sccm, and in Comparative Example 3, the oxygen flow rate was changed to 7 sccm.

Comparative Examples 4-5
An amorphous transparent conductive film was obtained in the same manner as in Example 3 except that the thickness, specific resistance, and hole density of the transparent substrate, amorphous ITO layer were changed to the materials or values shown in Table 1. (See FIG. 5). Specifically, in Comparative Example 4, the oxygen flow rate was changed to 7 sccm, and in Comparative Example 5, the oxygen flow rate was changed to 15 sccm.

(Crystallization treatment)
The amorphous transparent conductive films of each Example and each Comparative Example were heat-treated in a hot air circulation oven at 140 ° C. until the amorphous ITO layer crystallized.

  Thereby, the transparent conductive film of each Example and each comparative example was manufactured.

(Evaluation)
The following evaluation was implemented about the transparent conductive film (amorphous transparent conductive film and crystalline transparent conductive film) obtained by each Example and each comparative example. The results are shown in Table 1.

<Thickness of each layer>
The thickness of the transparent substrate was measured using a micro gauge thickness meter (manufactured by Mitutoyo Corporation).

  The thickness of the hard coat layer and the optical adjustment layer was calculated using the instantaneous multi-photometry system (“MCPD2000”, manufactured by Otsuka Electronics Co., Ltd.) on the basis of the interference spectrum waveform under the following conditions.

  The thickness of the amorphous ITO layer was calculated using a fluorescent X-ray analyzer (manufactured by Rigaku Corporation) under the following conditions.

  The thickness of the crystalline ITO layer after heating was the same as the thickness of the amorphous ITO layer before heating.

<Crystalization time>
The time until the amorphous ITO layer of the amorphous transparent conductive film of each example and each comparative example was crystallized was measured. Crystallization was performed by heating at 140 ° C. in a hot air circulating oven and performing the following “confirmation of change in resistance value (decrease) completion” and “etching test”.

  “Confirmation of completion of change (decrease) in resistance value”: Each amorphous transparent conductive film was heated at 140 ° C. in a hot air circulation oven, and the surface resistance value of the ITO layer was measured every 15 minutes. The surface resistance value decreased with crystallization, and when completed, the surface resistance value became constant. Therefore, the crystallization time was confirmed at the time when the surface resistance value became constant.

  “Etching test”: A transparent conductive film was immersed in hydrochloric acid (concentration 5 mass%) at 20 ° C. for 15 minutes, washed with water and dried, and then a resistance value (Ω) between two points 15 mm apart was measured by a tester (made by Custom) The product name “Digital Tester (M-04)” and the measurement limit value 2 MΩ) were measured to determine whether the ITO layer was crystallized. When the resistance value was detected, it was evaluated that the ITO layer was crystallized.

<Surface resistance value and specific resistance>
The surface resistance value (Ω / □) of the ITO layer of each transparent conductive film was measured using a four-terminal method. The specific resistance (Ω · cm) was calculated from the measured surface resistance value and the thickness of the ITO layer measured above.

<Hole mobility and carrier density>
Using a Hall effect measurement system (trade name “HL5500PC” manufactured by Bio-Rad), the hole mobility and carrier density of the ITO layer of each transparent conductive film were measured.

<Total light transmittance>
Using a haze meter (manufactured by Suga Test Instruments), the total light transmittance of each crystalline transparent conductive film was measured according to JIS K7105.

<Transmittance at 450 nm>
Using a high-speed integrating sphere spectral transmittance measuring device (“DOT-3”, manufactured by Murakami Color Research Laboratory Co., Ltd.), the transmittance T2 for light having a wavelength of 450 nm was measured for each crystalline transparent conductive film.

  Similarly, the transmittance T1 for light having a wavelength of 450 nm was measured for a transparent substrate (COP, PET film).

  Table 1 shows the transmittance T1, the transmittance T2, and the difference (T1-T2).

  According to Table 1, in the amorphous transparent conductive films of Examples 1 to 5, since the surface resistance value of the crystalline ITO layer in the crystalline transparent conductive film obtained by crystallization is 70Ω / □ or less, Good surface resistance. Moreover, since the total light transmittance is 83.0% or more and the amorphous ITO of Comparative Example 1 has a transmittance equivalent to that of 25 nm (thin film), the optical characteristics are good. . Further, the crystallization time is as short as 15 minutes, and the productivity is good.

  On the other hand, in the amorphous transparent conductive film of Comparative Example 1, since the thickness of the amorphous ITO layer is as thin as 25 nm, the surface resistance value of the crystalline ITO layer is 98 Ω / □ compared to Examples 1-2. It has a high resistance value.

The amorphous transparent conductive film of Comparative Example 2 has a high specific resistance of 9.8 × 10 ⁻⁴ Ω · cm and a low hole mobility of 14.6 cm ² / V · s. As compared with, the surface resistance value of the crystalline ITO layer is a high resistance value of 71 Ω / □. Moreover, the total light transmittance is 82.0%, the transmittance difference (T1-T2) is also 8.0%, and the optical characteristics are greatly deteriorated.

In the amorphous transparent conductive film of Comparative Example 3, since the specific resistance is as high as 8.3 × 10 ⁻⁴ Ω · cm, the surface resistance value of the crystalline ITO layer is 70 Ω / cm as compared with Examples 1-2. The resistance value is as high as □. Further, the total light transmittance is 82.6%, the transmittance difference (T1-T2) is also 7.4%, and the optical characteristics are deteriorated. Furthermore, the crystallization time is as long as 30 minutes, and the productivity is not good.

Since the amorphous transparent conductive film of Comparative Example 4 has a high specific resistance of 8.1 × 10 ⁻⁴ Ω · cm, the crystallization time is as long as 30 minutes as compared with Examples 3 to 5, and production The property is not good.

In the amorphous transparent conductive film of Comparative Example 5, the specific resistance is as low as 5.3 × 10 ⁻⁴ Ω · cm and the hole mobility is as high as 31.5 cm ² / V · s. As compared with, the surface resistance value of the crystalline ITO layer is a high resistance value of 87Ω / □. Further, the crystallization time is as long as 30 minutes, and the productivity is not good.

DESCRIPTION OF SYMBOLS 1 Amorphous transparent conductive film 2 Transparent base material 3A 1st hard-coat layer 4A 1st optical adjustment layer 5A 1st amorphous transparent conductive layer 6 Crystalline transparent conductive film 7A 1st crystalline transparent conductive layer

Claims (7)

A transparent base material and an amorphous transparent conductive layer are sequentially provided in the thickness direction,
The amorphous transparent conductive layer is made of amorphous indium tin composite oxide,
The amorphous transparent conductive layer has a thickness of 30 nm to 40 nm,
The amorphous transparent conductive layer has a specific resistance of 6.0 × 10 ⁻⁴ Ω · cm or more and 8.0 × 10 ⁻⁴ Ω · cm or less,
The amorphous transparent conductive film is characterized in that the hole mobility of the amorphous transparent conductive layer is 15.0 cm ² / V · s or more and 30.0 cm ² / V · s or less.   The amorphous transparent conductive film according to claim 1, further comprising an optical adjustment layer disposed between the transparent substrate and the amorphous transparent conductive layer.   The amorphous transparent conductive film according to claim 2, further comprising a hard coat layer disposed between the transparent substrate and the optical adjustment layer. Heating the amorphous transparent conductive film according to any one of claims 1 to 3,
A crystalline transparent conductive film comprising the transparent substrate and a crystalline transparent conductive layer made of crystalline indium / tin composite oxide in order in the thickness direction. 5. The crystalline transparent according to claim 4, wherein the specific resistance of the crystalline transparent conductive layer is 1.8 × 10 ⁻⁴ Ω · cm or more and 2.3 × 10 ⁻⁴ Ω · cm or less. Conductive film.   The difference between the transmittance of the crystalline transparent conductive film with respect to light having a wavelength of 450 nm and the transmittance of the transparent substrate with respect to light having a wavelength of 450 nm is 7.0% or less. Or 5. The crystalline transparent conductive film according to 5. Preparing an amorphous transparent conductive film comprising a transparent substrate and an amorphous transparent conductive layer made of amorphous indium-tin composite oxide in order in the thickness direction; and
Converting the amorphous indium tin composite oxide into a crystalline indium tin composite oxide by heating the amorphous transparent conductive film;
With
The amorphous transparent conductive layer has a thickness of 30 nm to 40 nm,
The amorphous transparent conductive layer has a specific resistance of 6.0 × 10 ⁻⁴ Ω · cm or more and 8.0 × 10 ⁻⁴ Ω · cm or less,
The method for producing a crystalline transparent conductive film, wherein the hole mobility of the amorphous transparent conductive layer is 15.0 cm ² / V · s or more and 30.0 cm ² / V · s or less.

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