JP2018170269A - Transparent conductive film for light control film and light control film - Google Patents

Abstract

The present invention provides a transparent conductive film for a light control film capable of increasing the acid resistance of a conductive layer and suppressing a change in the resistance value of the conductive layer exposed to an acidic condition. A transparent conductive film for a light control film according to the present invention is a transparent conductive film used for a light control film, and is a base film and a conductive film disposed on one surface side of the base film. And the conductive layer is an indium tin oxide layer, and in TOF-SIMS analysis, the intensity of InOH- ions at the center in the thickness direction of the conductive layer is the sum of the intensity of all negative ions The ratio is 0.0005 or less. [Selection] Figure 1

Description

  The present invention relates to a transparent conductive film used for a light control film. Moreover, this invention relates to the light control film using the said transparent conductive film.

  A light control material or the like is used for the light control film. The light modulating material is used for the purpose of adjusting the transmittance or adjusting the color tone by blocking light of a specific wavelength. The light control film is utilized in various fields, such as an indoor member, a building member, and an electronic component.

  For example, the light control film has a structure in which a light control layer is disposed between two transparent conductive films. The transparent conductive film used for the said light control film has a base film and a conductive layer on the surface of this base film. In the light control film, the conductive layer is opposed to the light control layer. In the light control film, an electric field is applied between the conductive layers of the two transparent conductive films. The amount of light passing through the light control film can be changed between a state where an electric field is applied and a state where no electric field is applied.

  An example of the transparent conductive film used for the light control film is disclosed in Patent Document 1 below. In the transparent conductive film described in Patent Document 1, the conductive layer may be formed of ITO or the like.

WO2008 / 075752A1

  In the light control film, in a method called PDLC (Polymer Dispersed Liquid Crystal), the light control layer is often formed using a liquid crystal layer and an acrylic resin as a binder resin. The conductive layer in contact with the light control layer formed using the acrylic resin is exposed to acidic conditions due to acrylic acid contained in a trace amount due to the acrylic resin. Further, the conductive layer may be exposed to acidic conditions due to external factors other than the light control layer.

  In the conventional transparent conductive film as described in Patent Document 1, the acid resistance of the conductive layer is low, and the resistance value may increase. As a result, the light control performance of the light control film may deteriorate.

  The objective of this invention is providing the transparent conductive film for light control films which can raise the acid resistance of a conductive layer and can suppress the change of the resistance value of the conductive layer exposed to acidic conditions. Another object of the present invention is to provide a light control film using the transparent conductive film for light control film.

According to a wide aspect of the present invention, there is provided a transparent conductive film used for a light control film, including a base film and a conductive layer disposed on one surface side of the base film, and the conductive film The layer is an indium tin oxide layer, and in TOF-SIMS analysis, the ratio of the intensity of InOH ⁻ ions at the central portion in the thickness direction of the conductive layer to the total intensity of all negative ions is 0.0005 or less. A transparent conductive film for a light control film is provided.

In a specific aspect of the transparent conductive film for a light control film according to the present invention, in the TOF-SIMS analysis, an In ⁺ ion having an intensity of H ₃ O ⁺ ion on the surface opposite to the base film side of the conductive layer. The ratio to the strength is 0.05 or less.

  On the specific situation with the transparent conductive film for light control films which concerns on this invention, the surface resistance value of the said conductive layer is 150 ohms / square or less.

  On the specific situation with the transparent conductive film for light control films which concerns on this invention, the total light transmittance in wavelength 550nm is 88% or more, and a haze value is 1.3% or less.

  On the specific situation with the transparent conductive film for light control films which concerns on this invention, the said transparent conductive film for light control films is used so that the said conductive layer may contact the light control layer containing an acrylic resin.

  According to a wide aspect of the present invention, the first transparent conductive film, the second transparent conductive film, and the light control layer disposed between the first transparent conductive film and the second transparent conductive film. A light control film is provided, wherein at least one of the first transparent conductive film and the second transparent conductive film is the above-described transparent conductive film for a light control film.

  On the specific situation with the light control film which concerns on this invention, the said light control layer contains an acrylic resin.

A transparent conductive film for a light control film according to the present invention is a transparent conductive film used for a light control film, and includes a base film and a conductive layer disposed on one surface side of the base film. The conductive layer is an indium tin oxide layer. In the transparent conductive film for a light control film according to the present invention, the ratio of the intensity of InOH ⁻ ions in the central portion in the thickness direction of the conductive layer to the total intensity of all negative ions is 0.0005 or less in TOF-SIMS analysis. It is. In the transparent conductive film for light control films according to the present invention, the above-described configuration is provided, so that the acid resistance of the conductive layer is increased and the change in the resistance value of the conductive layer exposed to acidic conditions is suppressed. Can do.

FIG. 1 is a cross-sectional view showing a transparent conductive film for a light control film according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing an example of a light control film using the transparent conductive film for light control film shown in FIG.

  Details of the present invention will be described below.

  The transparent conductive film for light control films according to the present invention (hereinafter sometimes referred to as a transparent conductive film) is used as a light control film. The transparent conductive film is transparent. Translucent includes translucent. The transparent conductive film has light transparency, for example. That the transparent conductive film has light transmittance means that, for example, the total light transmittance at a wavelength of 550 nm is preferably 88% or more, more preferably 89% or more.

  The transparent conductive film according to the present invention includes a base film and a conductive layer. The conductive layer is disposed on one surface side of the base film.

  In the transparent conductive film according to the present invention, the conductive layer is an indium tin oxide layer (ITO layer).

In the transparent conductive film according to the present invention, in TOF-SIMS analysis, the ratio of the intensity of InOH ⁻ ions at the central portion in the thickness direction of the conductive layer to the total intensity of all negative ions (InOH ⁻ ion intensity / total negative The total ion intensity) is 0.0005 or less. The surface opposite to the base film side of the conductive layer is the surface on the side where the light control layer is disposed. The surface opposite to the base film side of the conductive layer is, for example, the surface in contact with the light control layer.

  In the transparent conductive film which concerns on this invention, since said structure is provided, the acid resistance of a conductive layer is high and suppresses the change of the resistance value (sheet resistance value) of the conductive layer exposed to acidic conditions. Can do. As a result, a decrease in the light control performance of the light control film can be suppressed.

  In order to suppress the change in the resistance value of the conductive layer exposed to acidic conditions, the above strength ratio of the central portion in the thickness direction of the conductive layer is used instead of the surface opposite to the base film side of the conductive layer. It has been found that there is a need to control. This is because even if the surface of the conductive layer exposed to acidic conditions deteriorates, the deterioration is effectively suppressed inside the conductive layer (the region including the central part), so that the entire conductive layer is suppressed from deterioration. This is considered to be possible.

  In TOF-SIMS analysis, the intensity ratio at the central portion in the thickness direction of the conductive layer is measured as follows.

C60 sputtering is continuously performed at the same point on the surface opposite to the base film side of the conductive layer. When the number of sputters in which the number of detected In ⁺ ions is smaller than the number of detected Si ⁺ ions is an odd number, the center of the number of sputters in which the number of detected In ⁺ ions is smaller than the number of detected Si ⁺ ions. From the measurement result at the time of the number of (half) times, the strength ratio in the central portion of the conductive layer in the thickness direction is obtained. In ⁺ when sputtering the number of times the number of detection becomes less than the number of detected Si ⁺ ions of the ion is even, the center of the sputter number of detected number of In ⁺ ions becomes less than the number of detected Si ⁺ ions From the average value of the measurement results at the two times, the intensity ratio at the center in the thickness direction of the conductive layer is obtained.

In TOF-SIMS analysis, the ratio of the intensity of InOH ⁻ ions in the central portion of the conductive layer in the thickness direction to the total intensity of all negative ions is determined. From the viewpoint of further increasing the acid resistance of the conductive layer, the ratio (InOH ^- ion strength / total strength of all negative ions) is preferably 0.0004 or less, more preferably 0.0003 or less, and still more preferably. 0.0002 or less, particularly preferably 0.0001 or less. The above ratio (InOH ^- ion intensity / total of all negative ions intensity) is usually 0 or more.

In TOF-SIMS analysis, the ratio of the intensity of H ₃ O ⁺ ions to the intensity of In ⁺ ions on the surface of the conductive layer opposite to the base film side (H ₃ O ⁺ ion intensity / In ⁺ ion intensity) ) From the viewpoint of further increasing the acid resistance of the conductive layer, the ratio (H ₃ O ⁺ ion intensity / In ⁺ ion intensity) is preferably 0.05 or less, more preferably 0.04 or less, and still more preferably 0. 0.03 or less, particularly preferably 0.02 or less. The ratio (H ₃ O ⁺ ion intensity / In ⁺ ion intensity) is usually 0 or more.

  In the TOF-SIMS analysis, the strength ratio of the conductive layer on the surface opposite to the base film side is obtained from the measurement result of the first sputtering.

  As a method of controlling the intensity ratio within the above range, a method of controlling the total pressure during sputtering when a conductive layer is formed by sputtering, and a method of controlling a moisture pressure during sputtering when forming a conductive layer by sputtering. , And a method of controlling the film forming roll (can roll) temperature during RtR sputtering. The total pressure during the sputtering can be generally controlled by adjusting the volume of the vacuum part of the apparatus, the exhaust amount of the vacuum pump, the flow rate of a gas such as Ar introduced to generate plasma, and the like. In addition, the moisture pressure at the time of sputtering is adjusted by adjusting the vacuum holding time until the sputtering film formation is started, the pre-drying method of the base film, the flow rate of gas such as Ar introduced to generate plasma, and the like. Can be controlled. Further, the film forming roll temperature during the RtR sputtering can be controlled by adjusting the temperature of the refrigerant circulating in the film forming roll.

  The transparent conductive film is preferably used such that the conductive layer is in contact with a light control layer containing an acrylic resin. In the present invention, even if the conductive layer is in contact with the light control layer containing an acrylic resin, a change in the resistance value of the conductive layer can be suppressed. In the present invention, even if the conductive layer is in contact with the light control layer not containing the acrylic resin, the change in the resistance value of the conductive layer can be suppressed.

  The transparent conductive film is preferably an annealed transparent conductive film.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a transparent conductive film for a light control film according to an embodiment of the present invention.

  The transparent conductive film 1 shown in FIG. 1 is used for a light control film.

  The transparent conductive film 1 includes a base film 11 and a conductive layer 12.

  The base film 11 has light transmittance. The base film 11 is made of a light transmissive material. The base film 11 has a first surface 11a and a second surface 11b. The first surface 11a and the second surface 11b are opposed to each other.

  A conductive layer 12 is disposed on the first surface 11 a side of the base film 11. The conductive layer 12 is light transmissive. The conductive layer 12 is made of a material having high light transmittance and conductivity. The conductive layer 12 is directly laminated on the first surface 11 a of the base film 11. The conductive layer may not be directly laminated on the first surface of the base film. For example, an undercoat layer may be disposed between the conductive layer and the base film.

In the present embodiment, in the TOF-SIMS analysis, the ratio (InOH ⁻ ion intensity / total intensity of all negative ions) at the central portion in the thickness direction of the conductive layer 12 is not more than the above upper limit.

  Moreover, the transparent conductive film 1 shown in FIG. 1 may be wound in roll shape.

  From the viewpoint of further increasing the light transmittance, the total light transmittance of the transparent conductive film at a wavelength of 550 nm is preferably 88% or more, more preferably 89% or more. The total light transmittance at a wavelength of 550 nm of the transparent conductive film is usually 100% or less.

  The total light transmittance is measured based on JIS K7105 using a haze meter (“NDH-2000” manufactured by Nippon Denshoku Industries Co., Ltd. or equivalent).

  From the viewpoint of further enhancing the light transmittance, the haze value of the transparent conductive film is preferably 1.3% or less, more preferably 1% or less, and still more preferably 0.8% or less. The haze value of the transparent conductive film is usually 0% or more.

  The haze value is measured based on JIS K7136 using a haze meter (“NDH-2000” manufactured by Nippon Denshoku Industries Co., Ltd. or equivalent).

  Hereinafter, the detail of each layer which comprises a transparent conductive film is demonstrated.

(Base film)
The base film preferably has high light transmittance. Accordingly, the material of the base film is not particularly limited. For example, polyolefin, polyethersulfone, polysulfone, polycarbonate, cycloolefin polymer, polyarylate, polyamide, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate. Examples include phthalate, triacetylcellulose, and cellulose nanofiber. The material for the base film may be used alone or in combination.

  The thickness of the base film is preferably 5 μm or more, more preferably 20 μm or more, preferably 190 μm or less, more preferably 125 μm or less. When the thickness of the base film is not less than the above lower limit and not more than the above upper limit, the total thickness of the light control film can be reduced, and the handleability during production of the light control film can be improved.

  The average transmittance of the base film in the visible light region having a wavelength of 380 to 780 nm is preferably 85% or more, more preferably 90% or more. The average transmittance of the substrate film in the visible light region having a wavelength of 380 to 780 nm is usually 100% or less.

  Moreover, the base film may contain additives such as various stabilizers, ultraviolet absorbers, plasticizers, lubricants, and colorants. The said additive may be used independently and may use multiple together.

  The base film may have a hard coat layer on one or both surfaces.

  The material of the hard coat layer is preferably a cured resin. The said cured resin may be used independently and may use multiple.

  Examples of the curable resin include thermosetting resins and active energy ray curable resins such as ultraviolet curable resins. From the viewpoint of improving productivity and economy, the curable resin is preferably an ultraviolet curable resin.

  The ultraviolet curable resin is preferably a resin obtained by polymerizing a photocurable monomer. The ultraviolet curable resin may be a resin in which a monomer other than the photocurable monomer is polymerized. Monomers other than the photocurable monomer and the photocurable monomer may be used alone or in combination.

  Examples of the photocurable monomer include 1,6-hexanediol diacrylate, 1,4-butanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, tetraethylene glycol diacrylate, tripropylene glycol diacrylate, neo Pentyl glycol diacrylate, 1,4-butanediol dimethacrylate, poly (butanediol) diacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene glycol diacrylate, triethylene glycol diacrylate, triisopropylene glycol diacrylate, Diacrylate compounds such as polyethylene glycol diacrylate and bisphenol A dimethacrylate; trimethylol prop Triacrylate compounds such as triacrylate, trimethylolpropane trimethacrylate, pentaerythritol monohydroxytriacrylate and trimethylolpropane triethoxytriacrylate; tetraacrylate compounds such as pentaerythritol tetraacrylate and di-trimethylolpropane tetraacrylate; and dipenta Examples include pentaacrylate compounds such as erythritol (monohydroxy) pentaacrylate. The ultraviolet curable resin may be a polyfunctional acrylate compound having five or more functions. The said polyfunctional acrylate compound may be used independently and may use multiple together. Moreover, you may add a photoinitiator, a photosensitizer, a leveling agent, a diluent, etc. to the said polyfunctional acrylate compound.

  The hard coat layer may contain a filler. The hard coat layer may contain the cured resin and the filler. Examples of the filler include, but are not limited to, metal oxides such as silica, iron oxide, aluminum oxide, zinc oxide, titanium oxide, silicon dioxide, antimony oxide, zirconium oxide, tin oxide, cerium oxide, and indium-tin oxide. Product particles; and resin fine particles mainly composed of silicone, (meth) acryl, styrene, melamine, and the like. As the resin fine particles, resin fine particles such as crosslinked poly (meth) methyl acrylate can be used. The said filler may be used independently and may use multiple together.

(Conductive layer)
The conductive layer is made of a light-transmitting conductive material. The conductive material is ITO (indium tin oxide).

  The thickness of the conductive layer is preferably 12 nm or more, more preferably 16 nm or more, still more preferably 17 nm or more, preferably 50 nm or less, more preferably 30 nm or less, and even more preferably 19.9 nm or less.

  When the thickness of a conductive layer is more than the said minimum, the surface resistance value of the conductive layer of a transparent conductive film can be made low effectively, and electroconductivity can be improved further. When the thickness of the conductive layer is not more than the above upper limit, the transparent conductive film can be further reduced.

  The surface resistance value (sheet resistance value) of the conductive layer of the transparent conductive film is preferably 150Ω / □ or less, more preferably 130Ω / □ or less, and still more preferably 100Ω / □ or less. The surface resistance value of the conductive layer is usually 0Ω / □ or more. When the surface resistance value of the conductive layer is not more than the above upper limit, the driving speed of the light control film can be improved, and unevenness of the color tone can be suppressed.

  The surface resistance value of the conductive layer is measured on the surface side opposite to the base film side of the conductive layer, based on JIS K7194.

(Undercoat layer)
An undercoat layer may be disposed between the conductive layer and the base film. The undercoat layer is, for example, a refractive index adjustment layer. By disposing the undercoat layer, the difference in refractive index between the conductive layer and the base film (or the conductive layer and the hard coat layer when the base film has a hard coat layer) can be reduced. Since it can do, the light transmittance of a transparent conductive film can be improved further.

The material of the undercoat layer is not particularly limited as long as it is a material having a refractive index adjusting function. Examples of the material for the undercoat layer include inorganic materials such as SiO ₂ , MgF ₂ , and Al ₂ O ₃ , and organic materials such as acrylic resin, urethane resin, melamine resin, alkyd resin, and siloxane polymer.

  The undercoat layer can be formed by a vacuum deposition method, a sputtering method, an ion plating method, or a coating method.

When the material of the undercoat layer is SiO ₂ , a fully oxidized SiO ₂ layer and a partially oxidized SiO _x (0 ≦ x <2) layer can be obtained by adjusting a film forming process such as a sputtering method. A laminated undercoat layer can be formed. Specifically, the degree of oxidation of Si can be adjusted by adjusting the O ₂ partial pressure when forming a SiO ₂ layer by sputtering using a Si target. Further, the undercoat layer can enhance the adhesion between the case where the SiO _x layer, adhesion between the conductive layer and the SiO ₂ layer, and the substrate film and the SiO ₂ layer.

(Protective film)
The protective film may be arrange | positioned on the surface (on the other surface) opposite to the said conductive layer side of the said base film.

  The protective film is preferably composed of a base film sheet and an adhesive layer.

  The base film sheet preferably has high light transmittance. The material of the base film sheet is not particularly limited. For example, polyolefin, polyethersulfone, polysulfone, polycarbonate, cycloolefin polymer, polyarylate, polyamide, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate. Examples include phthalate, triacetylcellulose, and cellulose nanofiber.

  The pressure-sensitive adhesive layer can be composed of, for example, a (meth) acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, a urethane-based adhesive, or an epoxy-based adhesive. From the viewpoint of suppressing an increase in adhesive force due to heat treatment, the adhesive layer is preferably composed of a (meth) acrylic adhesive.

  The (meth) acrylic pressure-sensitive adhesive is a pressure-sensitive adhesive in which a crosslinking agent, a tackifier resin, various stabilizers, and the like are added to a (meth) acrylic polymer as necessary.

  The (meth) acrylic polymer is not particularly limited, but (meth) acrylic copolymer obtained by copolymerizing a mixed monomer containing a (meth) acrylic acid ester monomer and another copolymerizable monomer. A polymer is preferred.

  Although it does not specifically limit as said (meth) acrylic acid ester monomer, It is obtained by esterification reaction of the primary or secondary alkyl alcohol whose carbon number of an alkyl group is 1-12, and (meth) acrylic acid ( A meth) acrylic acid ester monomer is preferred. Specific examples of the (meth) acrylic acid ester monomer include ethyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylic acid-2-ethylhexyl. The said (meth) acrylic acid ester monomer may be used independently and may use multiple together.

  Examples of other copolymerizable polymerizable monomers include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate; Isobornyl (meth) acrylate, hydroxyalkyl (meth) acrylate, glycerin dimethacrylate, glycidyl (meth) acrylate, 2-methacryloyloxyethyl isocyanate, (meth) acrylic acid, itaconic acid, maleic anhydride, crotonic acid, malein Examples thereof include functional monomers such as acid and fumaric acid. The other copolymerizable polymerizable monomers may be used alone or in combination.

  The crosslinking agent is not particularly limited, and for example, an isocyanate crosslinking agent, an epoxy crosslinking agent, a melamine crosslinking agent, a peroxide crosslinking agent, a urea crosslinking agent, a metal alkoxide crosslinking agent, a metal chelate crosslinking agent. Agents, metal salt crosslinking agents, carbodiimide crosslinking agents, oxazoline crosslinking agents, aziridine crosslinking agents, amine crosslinking agents, polyfunctional acrylates and the like. The above crosslinking agents may be used alone or in combination.

  The tackifying resin is not particularly limited, and examples thereof include petroleum resins such as aliphatic copolymers, aromatic copolymers, aliphatic / aromatic copolymers, and alicyclic copolymers. Coumarone-indene resin; terpene resin; terpene phenol resin; rosin resin such as polymerized rosin; phenol resin; xylene resin. The tackifying resin may be a hydrogenated resin. The tackifying resins may be used alone or in combination.

  The thickness of the protective film is preferably 25 μm or more, more preferably 50 μm or more, preferably 300 μm or less, more preferably 200 μm or less. When the thickness of a protective film is more than the said minimum and below the said upper limit, it is excellent in the workability | operativity of a light control film, and can make handling at the time of manufacture favorable.

(Light control film)
The light control film which concerns on this invention is equipped with a 1st transparent conductive film, a 2nd transparent conductive film, and a light control layer. The light control layer is disposed between the first transparent conductive film and the second transparent conductive film. In the light control film according to the present invention, at least one of the first transparent conductive film and the second transparent conductive film is the transparent conductive film according to the present invention. One of the first transparent conductive film and the second transparent conductive film may be the transparent conductive film according to the present invention, and both the first transparent conductive film and the second transparent conductive film are The transparent conductive film according to the present invention may be used.

  FIG. 2 is a cross-sectional view showing an example of a light control film using the transparent conductive film for light control film shown in FIG.

  The light control film 21 includes two transparent conductive films 1 and a light control layer 31. A light control layer 31 is disposed between the two transparent conductive films 1. The conductive layer 12 in the transparent conductive film 1 is in contact with the light control layer 31.

  In the light control film 21, an electric field is applied between the conductive layers 12 of the two transparent conductive films 1. The amount of light passing through the light control film 21 can be changed between a state where an electric field is applied and a state where no electric field is applied.

  The light control layer may contain an acrylic resin. The light control layer may contain liquid crystal molecules in the acrylic resin. From the viewpoint of effectively improving the adhesion between the conductive layer and the light control layer, the light control layer preferably contains an acrylic resin.

  Hereinafter, the present invention will be described in more detail based on specific examples and comparative examples. The present invention is not limited to the following examples.

Example 1
Production of transparent conductive film:
A PET film having a thickness of 125 μm was prepared as a base film. An acrylic hard coat resin in which zirconia particles were dispersed was applied to one surface of the PET film to form a hard coat layer 1 having a thickness of 1.0 μm. An acrylic hard coat resin was applied to the other surface of the PET film to form a hard coat layer 2 having a thickness of 1.5 μm. In this way, a double-sided hard coat film was obtained.

This double-sided hard coat film was placed in a vacuum apparatus and evacuated. After reaching the vacuum degree of 9.0 × 10 ⁻⁴ Pa, argon gas was introduced so that the total pressure became 0.33 Pa, and the water pressure was set to 0. 0 with a process gas monitor (“Qulee CGM” manufactured by ULVAC). It waited until it became 0005 Pa. Next, a SiO _x layer (2 nm), a SiO ₂ layer (16 nm), and a SiO _x layer (2 nm) were formed in this order from the hard coat layer 1 side by DC magnetron sputtering, and indium tin oxide (ITO) was formed thereon. ) Layers were laminated. Specifically, the film forming roll (can roll) temperature of the RtR sputtering apparatus is set to −10 ° C., the ITO sintered body target with 7% by weight of SnO ₂ , and the cathode having the maximum horizontal magnetic flux density of 1000 gauss on the target surface. Was used to form a conductive layer (indium tin oxide layer) having a thickness of 17 nm. Then, a light-transmitting conductive film was obtained by performing an annealing treatment at 150 ° C. for 60 minutes in a hot air circulation oven.

(Examples 2 to 4 and Comparative Examples 1 to 3)
A transparent conductive film was obtained in the same manner as in Example 1 except that the conductive layer formation conditions (total sputtering pressure, moisture pressure during sputtering, and roll temperature) were set as shown in Table 1 below. The total sputtering pressure was controlled by adjusting the argon introduction flow rate. The moisture pressure at the time of sputtering was controlled by adjusting the vacuum holding time until the sputtering film formation was started and the pre-drying treatment method (drying temperature 105 ° C.) of the double-sided hard coat film.

(Evaluation)
(1) TOF-SIMS analysis Measurement in the thickness direction was performed by continuously performing C60 sputtering at the same point on the surface opposite to the base film side of the conductive layer. From the measurement result at the time of half the number of times of sputtering when the detected number of In ⁺ ions was smaller than the detected number of Si ⁺ ions, the intensity ratio (InOH ⁻ ion intensity / The total intensity of all negative ions) was determined.

Further, in the TOF-SIMS analysis, the intensity ratio (H ₃ O ⁺ ion intensity / In ⁺ ion intensity) was determined from the measurement result of the first sputtering on the surface opposite to the base film side of the conductive layer. Asked.

  Specific measurement conditions of TOF-SIMS are as follows.

TOF-SIMS apparatus: manufactured by ION-TOF, TOF-SIMS5 type primary ion: 209Bi ⁺¹
Ion voltage: 25 kV
Ion current: 1 pA
Mass range: 1 to 500 mass
Analysis area: 500μm
Charge prevention: Neutralization of electron irradiation Sputter ion: C60
Ion voltage: 20 keV
Ion current: 3 nA
Sputtering area: 300μm □

(2) Evaluation of acid resistance 1 The transparent conductive film was immersed in 1% by weight hydrochloric acid for 30 minutes. The change rate of the sheet resistance value (surface resistance value of the conductive layer) before and after immersion was determined. The ratio of the sheet resistance value Rs after immersion to the sheet resistance value Rs0 before immersion is preferably as close to 1.0 as possible. The sheet resistance value was measured based on JIS K7194 using “Loresta AX MCP-T370” manufactured by Mitsubishi Chemical Analytech.

(3) Evaluation of acid resistance 2 The transparent conductive film was immersed in 5 wt% hydrochloric acid for 30 minutes. The rate of change of the sheet resistance value (surface resistance value of the conductive layer) before and after immersion was determined in the same manner as in the evaluation of (2) acid resistance 1. The ratio of the sheet resistance value Rs after immersion to the sheet resistance value Rs0 before immersion is preferably as close to 1.0 as possible. In addition, when the sheet resistance value Rs was greatly deteriorated and was outside the measurement range range and the measurement result was not obtained, “not measured” is described in Table 1.

(4) Sheet resistance value (surface resistance value of conductive layer)
The sheet resistance value (surface resistance value of the conductive layer) of the obtained transparent conductive film was measured based on JIS K7194 using “Loresta AX MCP-T370” manufactured by Mitsubishi Chemical Analytech.

(5) Total light transmittance The total light transmittance at a wavelength of 550 nm of the obtained transparent conductive film was measured based on JIS K7105 using a haze meter (“NDH-2000” manufactured by Nippon Denshoku Industries Co., Ltd.). .

(6) Haze value The haze value of the obtained transparent conductive film was measured based on JIS K7136 using a haze meter ("NDH-2000" manufactured by Nippon Denshoku Industries Co., Ltd.).

  The formation conditions and results of the conductive layer are shown in Table 1 below.

DESCRIPTION OF SYMBOLS 1 ... Transparent conductive film 11 ... Base film 11a ... 1st surface 11b ... 2nd surface 12 ... Conductive layer 21 ... Light control film 31 ... Light control layer

Claims (7)

A transparent conductive film used for a light control film,
A base film, and a conductive layer disposed on one surface side of the base film, the conductive layer is an indium tin oxide layer,
In TOF-SIMS analysis, InOH at the center of the thickness direction of the conductive layer ^- the intensity of the ion, the ratio of the sum of the intensities of all the negative ions is 0.0005 or less, the transparent conductive film for light management films. 2. The ratio of the intensity of H ₃ O ⁺ ions to the intensity of In ⁺ ions on the surface opposite to the base film side of the conductive layer in TOF-SIMS analysis is 0.05 or less. Transparent conductive film for light control film.   The transparent conductive film for light control films of Claim 1 or 2 whose surface resistance value of the said conductive layer is 150 ohms / square or less. The total light transmittance at a wavelength of 550 nm is 88% or more,
The transparent conductive film for light control films of any one of Claims 1-3 whose haze value is 1.3% or less.   The transparent conductive film for light control films of any one of Claims 1-4 used so that the said conductive layer may contact the light control layer containing an acrylic resin. A first transparent conductive film;
A second transparent conductive film;
A light control layer disposed between the first transparent conductive film and the second transparent conductive film;
The light control film whose at least one of a said 1st transparent conductive film and a said 2nd transparent conductive film is a transparent conductive film for light control films of any one of Claims 1-5.   The light control film of Claim 6 in which the said light control layer contains an acrylic resin.

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