WO2019116719A1

WO2019116719A1 - Transparent conductive film

Info

Publication number: WO2019116719A1
Application number: PCT/JP2018/038786
Authority: WO
Inventors: 文彦河野; 圭祐松本; 豪彦安藤
Original assignee: 日東電工株式会社
Priority date: 2017-12-15
Filing date: 2018-10-18
Publication date: 2019-06-20
Also published as: JP2019107785A; TW201930085A; KR20200098484A; CN111372776A

Abstract

A transparent conductive film is provided with a transparent resin base, a hard coat layer, an optical control layer, an adhesive layer and a transparent conductive layer in this order. The adhesive layer is a resin layer containing nano silica particles, and the ratio of the number of silicon atoms to the number of carbon atoms in the transparent conductive layer-side surface of the adhesive layer is 0.50 or more.

Description

Transparent conductive film

The present invention relates to a transparent conductive film, and more particularly to a transparent conductive film suitably used for optical applications.

Conventionally, the transparent conductive film which formed the transparent conductive layer which consists of indium tin complex oxides in a desired electrode pattern is used for optical applications, such as a touch panel.

For example, in Patent Document 1, a transparent resin film, a hard coat layer, an intermediate layer, and a transparent conductive layer are sequentially provided, and the intermediate layer is made of metal oxide fine particles and an active energy ray-curable resin, and is refracted. A transparent conductive film having a ratio of 1.65 to 1.90 is disclosed. In the transparent conductive film of Patent Document 1 below, the coloring of transmitted light and the curling property of the film are suppressed, and the pattern portion and the non-pattern portion in the transparent conductive layer can not be distinguished, thereby making the appearance as a display element It is good.

JP, 2017-62609, A

However, the transparent conductive film of Patent Document 1 has low abrasion resistance. That is, when the surface of the transparent conductive layer is rubbed, the transparent conductive layer is broken, and a part thereof peels off and falls off the intermediate layer. As a result, the conductive performance is extremely poor.

Therefore, in order to suppress peeling of the transparent conductive layer, it is considered to provide an adhesive layer made of a resin between the intermediate layer and the transparent conductive layer (that is, on the lower surface of the transparent conductive layer).

However, when the adhesion layer is provided on the lower surface of the transparent conductive layer, the etching solution excessively etches the adhesion layer when etching the transparent conductive layer into a desired pattern (for example, an electrode pattern) with an etching solution or the like. More specifically, the adhesion layer portion in contact with the lower surface of the pattern portion of the transparent conductive layer is etched. As a result, the pattern portion is not supported by the adhesive layer, and a defect occurs in which the pattern portion is cracked. That is, it is inferior to the patterning characteristic.

An object of the present invention is to provide a transparent conductive film having good scratch resistance and patterning properties.

The present invention [1] comprises a transparent resin substrate, a hard coat layer, an optical adjustment layer, an adhesive layer, and a transparent conductive layer in this order, and the adhesive layer is a resin layer containing nanosilica particles. The surface of the adhesion layer on the transparent conductive layer side includes a transparent conductive film in which the ratio of the number of silicon atoms to the number of carbon atoms is 0.50 or more.

The present invention [2] includes the transparent conductive film according to [1], wherein the ratio of the number of silicon atoms to the number of carbon atoms is 1.00 or more.

The present invention [3] includes the transparent conductive film according to [1] or [2], wherein the thickness of the adhesion layer is 10 nm or more and 100 nm or less.

The present invention [4] includes the transparent conductive film according to any one of [1] to [3], wherein the transparent resin substrate is a cycloolefin polymer film.

According to the transparent conductive film of the present invention, the transparent resin substrate, the hard coat layer, the optical adjustment layer, the adhesion layer, and the transparent conductive layer are provided in this order, and the adhesion layer is a resin containing nanosilica particles. It is a layer. Therefore, the adhesiveness of an optical adjustment layer and a transparent conductive layer can be improved, and peeling and drop-off | omission of a transparent conductive layer can be suppressed. Therefore, it is excellent in abrasion resistance.

In addition, on the surface of the adhesion layer on the transparent conductive layer side, the ratio of the number of silicon atoms to the number of carbon atoms is 0.50 or more. Therefore, when etching a transparent conductive layer, the excessive etching with respect to a contact | glue layer can be suppressed, and the crack of a transparent conductive layer can be suppressed. Therefore, the patterning characteristic to the transparent conductive layer is good.

FIG. 1 shows a cross-sectional view of an embodiment of the transparent conductive film of the present invention. FIG. 2 shows a cross-sectional view of an embodiment in which the transparent conductive film shown in FIG. 1 is patterned. FIG. 3 shows a schematic view of a bending resistance test in an example.

<One embodiment>
One embodiment of the transparent conductive film of the present invention will be described with reference to FIGS.

In FIG. 1, the vertical direction in the drawing is the vertical direction (thickness direction, first direction), and the upper side of the drawing is the upper side (one side in the thickness direction, one side in the first direction), and the lower side is the lower side (thickness direction). The other side, the other side in the first direction). Further, the left-right direction and the depth direction in the drawing are surface directions orthogonal to the up-down direction. Specifically, it conforms to the directional arrow in each figure.

1. Transparent Conductive Film The transparent conductive film 1 has a film shape (including a sheet shape) having a predetermined thickness, extends in a predetermined direction (surface direction) orthogonal to the thickness direction, and has a flat upper surface and a flat lower surface. Have. The transparent conductive film 1 is, for example, one component such as a touch panel substrate provided in an image display device, that is, it is not an image display device. That is, the transparent conductive film 1 is a component for producing an image display device etc., does not include an image display element such as an LCD module, and an antiblocking layer 2, a transparent resin substrate 3 and a hard coat layer 4 described later. And an optical adjustment layer 5, an adhesive layer 6, and a transparent conductive layer 7. The component can be distributed alone and can be used industrially.

Specifically, as shown in FIG. 1, the transparent conductive film 1 includes a transparent resin substrate 3, an antiblocking layer 2 disposed on the lower surface (the other surface in the thickness direction) of the transparent resin substrate 3, and a transparent The hard coat layer 4 disposed on the upper surface (one surface in the thickness direction) of the resin substrate 3, the optical adjustment layer 5 disposed on the upper surface of the hard coat layer 4, and the adhesion layer disposed on the upper surface of the optical adjustment layer 5 6 and a transparent conductive layer 7 disposed on the upper surface of the adhesive layer 6. More specifically, the transparent conductive film 1 includes the antiblocking layer 2, the transparent resin substrate 3, the hard coat layer 4, the optical adjustment layer 5, the adhesion layer 6, and the transparent conductive layer 7. Prepare in order. The transparent conductive film 1 preferably comprises an antiblocking layer 2, a transparent resin base 3, a hard coat layer 4, an optical adjustment layer 5, an adhesive layer 6 and a transparent conductive layer 7.

2. Anti-blocking layer The anti-blocking layer 2 is the upper surface of one transparent conductive film 1 and the lower surface of the other transparent conductive film 1 disposed on the upper surface, for example, when a plurality of transparent conductive films 1 are laminated. Is a blocking resistant layer for suppressing a blocking phenomenon in which a part of any one of the transparent conductive films peels off when they are peeled off. Moreover, it is also a scratch protection layer for making it hard to produce a scratch on the upper surface (namely, upper surface of the transparent transparent conductive layer 7) of the transparent conductive film 1.

The antiblocking layer 2 is the lowermost layer of the transparent conductive film 1 and has a film shape (including a sheet shape). The antiblocking layer 2 is disposed on the entire lower surface of the transparent resin substrate 3 so as to be in contact with the lower surface of the transparent resin substrate 3.

The antiblocking layer 2 is formed of an antiblocking composition. The antiblocking layer 2 contains a resin and particles. That is, the antiblocking layer 2 is a resin layer containing particles.

As resin, a curable resin, a thermoplastic resin (for example, polyolefin resin) etc. are mentioned, for example, Preferably, a curable resin is mentioned.

As the curable resin, for example, an active energy ray curable resin which is cured by irradiation of active energy rays (specifically, ultraviolet rays, electron beams and the like), for example, a thermosetting resin which is cured by heating and the like can be mentioned. Preferably, an active energy ray curable resin is mentioned.

The active energy ray-curable resin includes, for example, a polymer having a functional group having a polymerizable carbon-carbon double bond in the molecule. As such a functional group, a vinyl group, a (meth) acryloyl group (methacryloyl group and / or an acryloyl group), etc. are mentioned, for example.

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

Moreover, as curable resin other than active energy ray curable resin, a urethane resin, a melamine resin, an alkyd resin, a siloxane type polymer, an organic silane condensate etc. are mentioned, for example.

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

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

Preferably, organic particles are mentioned, and more preferably, crosslinked acrylic particles are mentioned.

The average particle size (primary particle size) of the particles is, for example, 10 nm or more, preferably 100 nm or more, and for example, 5 μm or less, preferably 3 μm or less.

The average particle size of the particles indicates the average particle size (D ₅₀ ) of the particle size distribution on a volume basis, and for example, a solution in which the particles are dispersed in water can be measured by light diffraction / scattering method.

The content ratio of the particles is, for example, 0.1 parts by mass or more, preferably 0.2 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 below.

The antiblocking composition may further contain known additives such as leveling agent, thixotropy agent, antistatic agent and the like.

The thickness of the antiblocking layer 2 is, for example, 0.1 μm or more, preferably 0.5 μm or more, and, for example, 10 μm or less, preferably 3 μm, from the viewpoints of scratch resistance, antiblocking property, and removability. It is below. The thickness of the antiblocking layer 2 can be calculated, for example, based on the wavelength of the interference spectrum observed using an instantaneous multiphotometric system (for example, “MCPD 2000” manufactured by Otsuka Electronics Co., Ltd.).

3. Transparent Resin Base Material The transparent resin base material 3 is a transparent base material for securing the mechanical strength of the transparent conductive film 1. That is, the transparent resin base 3 supports the transparent conductive layer 7 together with the hard coat layer 4, the optical adjustment layer 5 and the adhesion layer 6.

The transparent resin substrate 3 has a film shape (including a sheet shape). The transparent resin substrate 3 is disposed on the entire upper surface of the antiblocking layer 2 so as to be in contact with the upper surface of the antiblocking layer 2. More specifically, the transparent resin substrate 3 is disposed between the antiblocking layer 2 and the hard coat layer 4 so as to be in contact with the upper surface of the antiblocking layer 2 and the lower surface of the hard coat layer 4 .

The transparent resin substrate 3 is, for example, a polymer film having transparency. The material of the transparent resin substrate 3 is, for example, a polyester resin such as polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate etc., for example (meth) acrylic resin (acrylic resin and / or methacrylic resin) such as polymethacrylate For example, an olefin resin such as polyethylene, polypropylene, cycloolefin polymer (for example, norbornene type, cyclopentadiene type), for example, polycarbonate resin, polyether sulfone resin, polyarylate resin, melamine resin, polyamide resin, polyimide resin, cellulose resin And polystyrene resins. The transparent resin substrate 3 can be used alone or in combination of two or more.

The transparent resin substrate 3 is preferably a cycloolefin polymer film (COP film) from the viewpoint of high transparency and low birefringence.

The tensile strength at break of the transparent resin base material 3 is, for example, 10 MPa or more, preferably 30 MPa or more, and for example, 100 MPa or less, preferably 85 MPa or less. If the tensile strength at break is within the above range, the transparent resin substrate 3 can be favorably transported when adopting the transparent conductive film 1 by the roll-to-roll method, and the transparent resin substrate 3 may be cracked or the like. Damage can be suppressed.

The tensile strength at break can be measured in accordance with ISO 527.

The total light transmittance (JIS K 7375-2008) of the transparent resin substrate 3 is, for example, 80% or more, preferably 85% or more.

The thickness of the transparent resin substrate 3 is, for example, 2 μm or more, preferably 20 μm or more, from the viewpoints of mechanical strength, hitting characteristics when the transparent conductive film 1 is used as a film for touch panel, etc. It is 300 μm or less, preferably 150 μm or less, more preferably 50 μm or less. The thickness of the transparent resin substrate 3 can be measured, for example, using a micro gauge type thickness meter.

4. Hard Coat Layer The hard coat layer 4 is a protective layer for suppressing the occurrence of scratches on the transparent resin substrate 3 when producing the transparent conductive film 1. Moreover, when laminating | stacking the several transparent conductive film 1, it is an abrasion-resistant layer for suppressing that abrasion generate | occur | produces in the transparent conductive layer 7. As shown in FIG. Furthermore, it is also a layer for imparting bending resistance.

The hard coat layer 4 has a film shape (including a sheet shape). The hard coat layer 4 is disposed on the entire upper surface of the transparent resin substrate 3 so as to be in contact with the upper surface of the transparent resin substrate 3. More specifically, the hard coat layer 4 is disposed between the transparent resin base 3 and the optical adjustment layer 5 so as to be in contact with the upper surface of the transparent resin base 3 and the lower surface of the optical adjustment layer 5 There is.

The hard coat layer 4 is formed of a hard coat composition. The hard coat composition contains a resin. That is, the hard coat layer 4 is a resin layer.

Although it does not specifically limit as resin, For example, resin illustrated by the anti blocking composition is mentioned. Preferably, a curable resin, more preferably, an active energy ray curable resin, and still more preferably, a (meth) acrylic ultraviolet curable resin can be mentioned.

The hardcoat composition can also contain particles. Thereby, the hard-coat layer 4 can be made into the anti blocking layer which has a blocking resistance characteristic. Although it does not specifically limit as a particle | grain, The particle | grains illustrated by the anti blocking composition are mentioned.

The hard coat composition may further contain known additives such as leveling agents, thixotropy agents, antistatic agents and the like.

The thickness of the hard coat layer 4 is, for example, 0.1 μm or more, preferably 0.5 μm or more, and for example, 10 μm or less, preferably 3 μm or less, from the viewpoint of scratch resistance. The thickness of the hard coat layer 4 can be calculated, for example, based on the wavelength of the interference spectrum observed using an instantaneous multiphotometric system.

5. Optical Adjustment Layer The optical adjustment layer 5 controls optical properties of the transparent conductive film 1 (eg, for example, in order to ensure excellent transparency of the transparent conductive film 1 while suppressing visual recognition of the wiring pattern in the transparent conductive layer 7). Layer to adjust the refractive index).

The optical adjustment layer 5 has a film shape (including a sheet shape), and is disposed on the entire top surface of the hard coat layer 4 so as to be in contact with the top surface of the hard coat layer 4. More specifically, the optical adjustment layer 5 is disposed between the hard coat layer 4 and the adhesion layer 6 so as to be in contact with the upper surface of the hard coat layer 4 and the lower surface of the adhesion layer 6.

The optical adjustment layer 5 is formed of an optical adjustment composition. The optical modulating composition contains a resin, preferably containing a resin and particles. That is, the optical adjustment layer 5 is preferably a resin layer containing particles.

The content ratio of the resin 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 optical adjustment composition.

As a particle | grain, a suitable material can be selected according to the refractive index for which an optical adjustment layer seeks, For example, the particle | grains illustrated by the anti blocking composition are mentioned. From the viewpoint of the refractive index, preferably inorganic particles, more preferably metal oxide particles, further preferably zirconium oxide particles (ZnO ₂ ) can be mentioned.

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 optical adjustment composition.

The optical adjustment composition may further contain known additives such as leveling agents, thixotropes, and antistatic agents.

The refractive index of the optical adjustment layer 5 is, for example, 1.40 or more, preferably 1.55 or more, and for example, 1.80 or less, preferably 1.70 or less. The refractive index can be measured, for example, by an Abbe refractometer.

The thickness of the optical adjustment layer 5 is, for example, 5 nm or more, preferably 10 nm or more, and for example, 100 nm or less, preferably 50 nm or less. The thickness of the optical adjustment layer 5 can be calculated based on, for example, the wavelength of the interference spectrum observed using an instantaneous multiphotometric system.

6. Adhesion Layer In the adhesion layer 6, when the transparent conductive layer 7 is scratched, the transparent conductive layer 7 and the optical adjustment are performed in order to suppress peeling and detachment of part of the transparent conductive layer 7 from the transparent conductive film 1. It is a layer that adjusts (improves) the adhesion to the layer 5.

The adhesion layer 6 has a film shape (including a sheet shape), and is disposed on the entire upper surface of the optical adjustment layer 5 so as to be in contact with the upper surface of the optical adjustment layer 5. More specifically, the adhesion layer 6 is disposed between the optical adjustment layer 5 and the transparent conductive layer 7 so as to be in contact with the upper surface of the optical adjustment layer 5 and the lower surface of the transparent conductive layer 7.

The adhesion layer 6 is formed of an adhesion composition. The adhesion composition contains a resin and nanosilica particles. That is, the adhesion layer 6 is a resin layer containing nano silica particles. As a result, the adhesion layer 6 reliably adheres to both the optical adjustment layer 5 and the transparent conductive layer 7 and it is possible to suppress the detachment of these.

The content ratio of the resin is, for example, 10% by mass or more, preferably 25% by mass or more, and for example, 50% by mass or less, preferably 40% by mass or less, based on the adhesion composition. If the content ratio of the resin is in the above range, it is possible to suppress the decrease in the etching rate of the transparent conductive layer 7 due to the excessive adhesion between the adhesion layer 6 and the transparent conductive layer 7.

The average particle size (primary particle size) of the nanosilica particles is, for example, 1 nm or more, preferably 5 nm or more, and for example, 100 nm or less, preferably 30 nm or less, more preferably 20 nm or less.

The average particle size of the nanosilica particles indicates the average particle size (D ₅₀ ) of the particle size distribution based on volume, and for example, a solution in which the particles are dispersed in water can be measured by light diffraction / scattering method.

The content ratio of the nanosilica particles is, for example, 50% by mass or more, preferably 60% by mass or more, and for example, 90% by mass or less, preferably 75% by mass or less, with respect to the adhesion composition. If the content rate of nano silica particles is more than the above-mentioned lower limit, ratio of the number of silicon atoms in the upper surface of adhesion layer 6 can be made into a desired range, and patterning characteristics can be improved. Moreover, if the content rate of nano silica particle is below the said upper limit, it can suppress that the etching rate of the transparent conductive layer 7 falls because of the excessive adhesion of the contact layer 6 and the transparent conductive layer 7.

The adhesion composition may further contain known additives such as a leveling agent, a thixotropy agent, and an antistatic agent.

The ratio of the number of silicon atoms to the number of carbon atoms (Si / C) is 0.50 or more, preferably 1.00 or more, on the upper surface (the surface on the transparent conductive layer 7 side) of the adhesion layer 6. , 2.00 or less. If the ratio is equal to or more than the above lower limit, erosion of the adhesion layer 6 (particularly, the adhesion layer 6 in contact with the lower surface of the transparent conductive layer 7) by the etching solution can be suppressed at the time of etching the transparent conductive layer 7. Cracks in the patterned transparent conductive layer 7 can be suppressed. As a result, the patterning characteristics are excellent.

The ratio (Si / C) can be measured by X-ray photoelectron spectroscopy (electron spectroscopy for chemical analysis, ESCA). Specific conditions will be described later in the examples.

The thickness of the adhesion layer 6 is, for example, 10 nm or more, preferably 20 nm or more, and for example, 100 nm or less, preferably 50 nm or less. The thickness of the adhesion layer 6 can be calculated, for example, based on the wavelength of the interference spectrum observed using an instantaneous multiphotometric system.

7. Transparent Conductive Layer The transparent conductive layer 7 is a conductive layer for crystallization as necessary and forming a desired pattern in a later step to form a transparent pattern portion 8 (described later).

The transparent conductive layer 7 is the uppermost layer of the transparent conductive film 1 and has a film shape (including a sheet shape). The transparent conductive layer 7 is disposed on the entire upper surface of the adhesive layer 6 so as to be in contact with the upper surface of the adhesive layer 6.

The material of the transparent conductive layer 7 is, for example, at least one selected from the group consisting of In, Sn, Zn, Ga, Sb, Ti, Si, Zr, Mg, Al, Au, Ag, Cu, Pd, W. And metal oxides containing the following metals. The metal oxide may further be doped with the metal atoms shown in the above group, as needed.

Specific examples of the transparent conductive layer 7 include indium-containing oxides such as indium tin complex oxide (ITO), and antimony-containing oxides such as antimony tin complex oxide (ATO). Preferably, indium-containing oxides, more preferably ITO can be mentioned.

When the transparent conductive layer 7 is an indium tin complex oxide layer such as an ITO layer, the tin oxide (SnO ₂ ) content is, for example, 0 with respect to the total amount of tin oxide and indium oxide (In ₂ O ₃ ). .5 mass% or more, preferably 3 mass% or more, and for example, 15 mass% or less, preferably 13 mass% or less. If content of a tin oxide is more than the said minimum, durability of the transparent conductive layer 7 can be made still more favorable. If content of a tin oxide is below the said upper limit, crystal | crystallization conversion of the transparent conductive layer 7 can be made easy, and stability of transparency and surface resistance can be improved.

In the present specification, “ITO” 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, and specifically, Zn, Ga, Sb, Ti, Si, Zr, Mg, Al, Au, Ag, Cu, Pd, W, Fe , Pb, Ni, Nb, Cr, Ga and the like.

The surface resistance of the transparent conductive layer 7 is, for example, 200 Ω / sq or more, preferably 250 Ω / sq or more, and for example, 500 Ω / sq or less. The surface resistance can be measured by the four probe method.

The thickness of the transparent conductive layer 7 is, for example, 10 nm or more, preferably 15 nm or more, and for example, 50 nm or less, preferably 30 nm or less. The thickness of the transparent conductive layer 7 can be measured, for example, using an instantaneous multiphotometric system.

Transparent conductive layer 7 may be either amorphous or crystalline.

If the transparent conductive layer is amorphous or crystalline, for example, if the transparent conductive layer is an ITO layer, it is immersed in hydrochloric acid (concentration 5 mass%) at 20 ° C. for 15 minutes, then washed with water and dried, about 15 mm Can be determined by measuring the resistance between the terminals. In this specification, if the resistance between terminals exceeds 15 kΩ after immersion in water (20 ° C., concentration: 5% by mass), washing with water, and drying, the ITO layer is made amorphous and between 15 mm When the resistance between terminals is 10 kΩ or less, the ITO layer is crystalline.

7. Method of Producing Transparent Conductive Film Next, a method of producing the transparent conductive film 1 will be described. In order to produce the transparent conductive film 1, for example, the antiblocking layer 2 is provided on the lower surface (the other surface in the thickness direction) of the transparent resin substrate 3, and on the upper surface (the one surface in the thickness direction) , Hard coat layer 4 is provided. Then, on the upper surface of the hard coat layer 4, the optical adjustment layer 5, the adhesion layer 6, and the transparent conductive layer 7 are provided in this order. The details will be described below.

First, a known or commercially available transparent resin substrate 3 is prepared.

Then, from the viewpoint of adhesion between the transparent resin substrate 3 and the antiblocking layer 2 or the hard coat layer 4, for example, sputtering, corona discharge, or flame on the lower surface or the upper surface of the transparent resin substrate 3. It is possible to carry out etching treatment such as ultraviolet irradiation, electron beam irradiation, chemical formation, oxidation, etc. In addition, the transparent resin substrate 3 can be dust-removed and cleaned by solvent cleaning, ultrasonic cleaning, or the like.

Next, the antiblocking layer 2 is provided on the lower surface of the transparent resin substrate 3. For example, the antiblocking layer 2 is formed on the lower surface of the transparent resin substrate 3 by wet coating the antiblocking composition on the lower surface of the transparent resin substrate 3.

Specifically, for example, the antiblocking composition is diluted with a solvent to prepare a solution (varnish), and subsequently, the antiblocking composition solution is applied to the lower surface of the transparent resin substrate 3 and dried.

As a solvent, an organic solvent, an aqueous solvent (specifically, water) etc. are mentioned, for example, Preferably, an organic solvent is mentioned. 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, propylene glycol monomethyl ether (PGME) And ether compounds such as aromatic compounds such as toluene and xylene. These solvents can be used alone or in combination of two or more.

The solid concentration in the composition 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.

The coating method can be appropriately selected according to the antiblocking composition solution and the transparent resin substrate 3. Examples of the coating method include dip coating method, air knife coating method, curtain coating method, roller coating method, wire bar coating method, gravure coating method, extrusion coating method and the like.

The drying temperature is, for example, 50 ° C. or more, preferably 70 ° C. or more, and for example, 200 ° C. or less, preferably 100 ° C. or less.

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

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

In addition, when an antiblocking composition contains a thermosetting resin, a thermosetting resin can be thermosetted with drying of a solvent by this drying process.

On the other hand, the hard coat layer 4 is provided on the upper surface of the transparent resin substrate 3. For example, the hard coat layer 4 is formed on the upper surface of the transparent resin substrate 3 by wet-coating the hard coat composition on the upper surface of the transparent resin substrate 3.

Specifically, for example, a solution (varnish) in which the hard coat composition is diluted with a solvent is prepared, and then the hard coat composition solution is applied to the upper surface of the transparent resin substrate 3 and dried.

The conditions such as preparation, coating and drying of the hard coat composition can be the same as the conditions such as preparation, coating and drying exemplified for the antiblocking composition.

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

In addition, when a hard-coat composition contains a thermosetting resin, a thermosetting resin can be thermosetted with drying of a solvent by this drying process.

Next, the optical adjustment layer 5 is provided on the upper surface of the hard coat layer 4. For example, the optical adjustment layer 5 is formed on the upper surface of the hard coat layer 4 by wet-coating the optical adjustment composition on the upper surface of the hard coat layer 4.

Specifically, for example, a solution (varnish) in which the optical adjustment composition is diluted with a solvent is prepared, and subsequently, the optical adjustment composition solution is applied to the upper surface of the hard coat layer 4 and dried.

The conditions such as preparation, coating and drying of the optical adjustment composition can be the same as the conditions such as preparation, coating and drying exemplified for the antiblocking composition.

Moreover, when an optical adjustment composition contains active energy ray curable resin, active energy ray curable resin is hardened by irradiating an active energy ray after drying of an optical adjustment composition solution.

In addition, when an optical adjustment composition contains a thermosetting resin, a thermosetting resin can be thermosetted with drying of a solvent by this drying process.

Next, the adhesion layer 6 is provided on the upper surface of the optical adjustment layer 5. For example, the adhesion layer 6 is formed on the upper surface of the optical adjustment layer 5 by wet coating the adhesion composition on the upper surface of the optical adjustment layer 5.

Specifically, for example, a solution (varnish) obtained by diluting the adhesion composition with a solvent is prepared, and subsequently, the adhesion composition solution is applied to the upper surface of the optical adjustment layer 5 and dried.

The conditions such as preparation, coating and drying of the adhesive composition can be the same as the conditions such as preparation, coating and drying exemplified for the antiblocking composition.

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

In addition, when an adhesion composition contains a thermosetting resin, a thermosetting resin can be thermosetted with drying of a solvent by this drying process.

Next, the transparent conductive layer 7 is provided on the upper surface of the adhesive layer 6. For example, the transparent conductive layer 7 is formed on the upper surface of the adhesive layer 6 by a dry method.

As a dry method, a vacuum evaporation method, sputtering method, ion plating method etc. are mentioned, for example. Preferably, a sputtering method is mentioned. A thin transparent conductive layer 7 can be formed by this method.

When the sputtering method is employed, the above-mentioned inorganic substance constituting the transparent conductive layer 7 is mentioned as a target material, and preferably ITO is mentioned. The tin oxide concentration of ITO is, for example, 0.5% by mass or more, preferably 3% by mass or more, and for example, 15% by mass or less, preferably, from the viewpoint of durability of the ITO layer, crystallization, etc. , 13 mass% or less.

As sputtering gas, inert gas, such as Ar, is mentioned, for example. Moreover, reactive gases, such as oxygen gas, can be used together as needed. When the reactive gas is used in combination, the flow ratio of the reactive gas is not particularly limited, but is, for example, 0.1 flow% to 5 flow% with respect to the total flow ratio of the sputtering gas and the reactive gas.

The sputtering method is carried out under vacuum. Specifically, the atmospheric pressure at the time of sputtering is, for example, 1 Pa or less, preferably 0.7 Pa or less, from the viewpoint of suppression of a decrease in sputtering rate, discharge stability, and the like.

The power source used for the sputtering method 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.

Moreover, in order to form the transparent conductive layer 7 of desired thickness, you may set a target material, the conditions of sputtering, etc. suitably and may implement sputtering multiple times.

In the above manufacturing method, the transparent resin substrate 3 is transported by the roll-to-roll method while the transparent resin substrate 3 includes the antiblocking layer 2, the hard coat layer 4, the optical adjustment layer 5, and the adhesive layer 6. And the transparent conductive layer 7 may be formed, and some or all of these layers may be formed by a batch system (single wafer system). From the viewpoint of productivity, each layer is preferably formed on the transparent resin substrate 3 while being conveyed by the roll-to-roll method.

Thereby, as shown in FIG. 1, the transparent conductive film 1 provided with the antiblocking layer 2, the transparent resin base material 3, the hard coat layer 4, the optical adjustment layer 5, the adhesion layer 6, and the transparent conductive layer 7 in order is obtained. . The transparent conductive film 1 shown in FIG. 1 is a non-patterned transparent conductive film which has not been patterned.

The thickness of the transparent conductive film 1 obtained is, for example, 2 μm or more, preferably 20 μm or more, and for example, 300 μm or less, preferably 100 μm or less, more preferably 50 μm or less.

Then, as necessary, the non-patterned transparent conductive film is patterned by known etching to form the transparent conductive layer 7.

Although the pattern of the transparent conductive layer 7 is suitably determined according to the use to which the transparent conductive film 1 is applied, electrode patterns, such as stripe form, and a wiring pattern are mentioned, for example.

In the etching, for example, a covering portion (such as a masking tape) is disposed on the transparent conductive layer 7 so as to correspond to the pattern portion 8 and the non-pattern portion 9, and the transparent conductive layer 7 (non-patterning portion exposed from the covering portion 9) etch using an etching solution. Examples of the etching solution include acids such as hydrochloric acid, sulfuric acid, nitric acid, acetic acid, oxalic acid, phosphoric acid and mixed acids thereof. Thereafter, the covering portion is removed from the upper surface of the transparent conductive layer 7 by, for example, peeling.

Thereby, as shown in FIG. 2, the patterning transparent conductive film 1a by which the transparent conductive layer 7 was patterned is mentioned.

In addition, before or after the etching, crystal conversion treatment is performed on the transparent conductive layer 7 of the transparent conductive film 1 as necessary.

Specifically, the heat treatment is performed on the transparent conductive film 1 under the atmosphere.

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

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. When the heating temperature is in the above range, crystal conversion can be ensured while suppressing thermal damage to the transparent resin substrate 3 and impurities generated from the transparent resin substrate 3.

The heating time is appropriately determined according to the heating temperature, and is, for example, 10 minutes or more, preferably 30 minutes or more, and for example, 5 hours or less, preferably 3 hours or less.

Thereby, the transparent conductive film 1 in which the transparent conductive layer 7 is crystallized is obtained.

The transparent conductive film 1 is provided, for example, in an optical device. As an optical apparatus, an image display apparatus etc. are mentioned, for example. When the transparent conductive film 1 is provided in an image display device (specifically, an image display device having an image display element such as an LCD module), the transparent conductive film 1 is used, for example, as a touch panel substrate . As a type of touch panel, various types such as an optical type, an ultrasonic type, an electrostatic capacity type, and a resistive film type can be mentioned, and in particular, it is suitably used for an electrostatic capacity type touch panel.

And this transparent conductive film 1 is provided with the transparent resin base material 3, the hard-coat layer 4, the optical adjustment layer 5, the contact | adherence layer 6, and the transparent conductive layer 7 in this order. The adhesion layer 6 is a resin layer containing nano silica particles. Therefore, the adhesion between the optical adjustment layer 5 and the transparent conductive layer 7 can be improved. Therefore, even if the upper surface of the transparent conductive film 1 is rubbed and the transparent conductive layer 7 is broken, the transparent conductive layer 7 can be maintained on the surface of the transparent conductive film 1 by the presence of the adhesive layer 6. That is, peeling and falling off of the transparent conductive layer 7 can be suppressed. As a result, it is possible to suppress a significant decrease in the conductive performance (specifically, an excessive increase in the surface resistance value) due to the loss of the transparent conductive layer 7. Therefore, it is excellent in abrasion resistance.

Further, on the upper surface of the adhesion layer 6, the ratio of the number of silicon atoms to the number of carbon atoms (Si / C) is 0.50 or more. Therefore, since silicon atoms (nanosilica particles) are sufficiently present on the upper surface of adhesion layer 6, the etching liquid etches adhesion layer 6 (especially transparent conductive layer 7) when etching transparent conductive layer 7 with the etching solution. Etching of the adhesion layer portion in contact with the lower surface of the substrate. As a result, it is possible to suppress the occurrence of cracks in the transparent conductive layer 7 caused by the loss of the adhesive layer 6 supporting the transparent conductive layer 7. Therefore, the patterning characteristic to transparent conductive layer 7 is good.

Moreover, this transparent conductive film 1 is provided with the transparent resin base material 3 and the hard-coat layer 4 arrange | positioned on the upper surface. Therefore, the transparent resin substrate 3 is reliably protected by the hard coat layer 4. Therefore, when the transparent conductive layer 7 is formed on the upper side of the transparent resin substrate 3 (particularly, the COP film which is a soft substrate) by a dry method (particularly, sputtering method), generation of scratches on the transparent resin substrate 3 is It can be suppressed. Therefore, the appearance of the transparent conductive film 1 can be improved. Furthermore, since the hard coat layer 4 is provided, breakage and breakage at the time of bending can be suppressed, and the bending resistance is excellent.

In addition, in the transparent conductive film 1, preferably, the transparent resin substrate 3 is a COP film. The COP film is useful in that it prevents the depolarization of the polarizing plate and the film for a touch panel because the birefringence is lower than that of other resin films such as PET film and the retardation is substantially zero. . However, since the COP film is soft, it is more likely to cause, for example, a defect of the transparent conductive layer 7 due to abrasion than other resin films such as a PET film. And according to this transparent conductive film 1, the said subject by abrasion and patterning is solved especially with respect to the case where such a transparent resin base material 3 is a COP film, Furthermore, the transparent resin base material 3 It is also possible to solve the problem of poor appearance due to scratches.

<Modification>
In one embodiment, the transparent conductive film 1 includes the antiblocking layer 2 disposed on the lower surface of the transparent resin substrate 3. For example, although not shown, other functions may be used instead of the antiblocking layer 2. A layer may be provided. As a functional layer, the above-mentioned hard-coat layer 4 etc. are mentioned, for example.

Moreover, although the transparent conductive film 1 is equipped with the antiblocking layer 2 arrange | positioned on the lower surface of the transparent resin base material 3 in one embodiment, although not shown in figure, even if it does not comprise the antiblocking layer 2, for example. Good. That is, the transparent conductive film 1 may include only the transparent resin substrate 3, the hard coat layer 4, the optical adjustment layer 5, the adhesive layer 6, and the transparent conductive layer 7.

Hereinafter, the present invention will be described more specifically by showing Examples and Comparative Examples. The present invention is not limited to the examples and comparative examples. In addition, specific numerical values such as mixing ratios (content ratios), physical property values, parameters, etc. used in the following description are the mixing ratios corresponding to those described in the above-mentioned “embodiments for carrying out the invention” Substitutes the upper limit (numerical value defined as "below", "less than") or lower limit (numerical value defined as "above", "excess"), etc. of the corresponding description such as content ratio), physical property value, and parameters be able to.

Example 1
As a transparent resin substrate, a norbornene resin film (COP film, thickness 40 μm, manufactured by Nippon Zeon Co., Ltd., “Zeonor film”, tensile breaking strength 76 MPa) was prepared.

100 parts by mass of a resin composition solution having a UV-curing property (a mixture of 80% by mass of "U-DIC ELS-888" manufactured by DIC, and 20% by mass of "U-Unid RS-605" manufactured by DIC) And 0.4 parts by mass of crosslinked acrylic particles (average particle diameter: 1.8 μm, manufactured by Soken Chemical & Engineering Co., Ltd., “MX-180TA”) were mixed to prepare an antiblocking composition solution. The lower surface of the transparent resin substrate was coated with the antiblocking composition solution and dried at 80 ° C. for 1 minute. Thereafter, the antiblocking composition was cured by irradiating ultraviolet light with an ozone type high pressure mercury lamp. Thus, an antiblocking layer having a thickness of 1.0 μm was formed.

On the other hand, a hard coat composition solution (acrylic resin composition, manufactured by Aika Kogyo Co., Ltd., "Z-850-6L") having ultraviolet curability is applied to the upper surface of the transparent resin substrate, and dried at 80 ° C for 1 minute did. Thereafter, ultraviolet rays were irradiated with an ozone type high pressure mercury lamp to cure the hard coat composition. Thus, a hard coat layer having a thickness of 1.0 μm was formed.

Next, an optical adjustment composition solution having ultraviolet curability (containing zirconia oxide particles, manufactured by Arakawa Chemical Industries, "Opster KZ6955") is applied to the upper surface of the hard coat layer on the upper surface of the hard coat layer, and 1 at 60 ° C. Dried for a minute. Thereafter, ultraviolet light was irradiated with an ozone type high pressure mercury lamp to cure the optical control composition. Thus, an optical adjustment layer having a thickness of 25 nm and a refractive index of 1.68 was formed.

Next, a composition solution containing 60 parts by mass of nano silica particles (average primary particle diameter: 10 nm), 40 parts by mass of acrylic resin, and a solvent (PGME) as an adhesive composition having ultraviolet curability (manufactured by Arakawa Chemical Co., Ltd.) "Opster Z7549" was prepared. The adhesion composition solution was applied to the upper surface of the optical adjustment layer and dried at 60 ° C. for 1 minute. Thereafter, ultraviolet light was irradiated with an ozone type high pressure mercury lamp to cure the adhesion composition. Thereby, the adhesion layer with a thickness of 40 nm was formed.

Next, an amorphous ITO layer (transparent conductive layer) having a thickness of 26 nm was formed on the upper surface of the adhesion layer by DC sputtering. Specifically, an ITO target consisting of a sintered body of 80% by mass of indium oxide and 20% by mass of tin oxide was sputtered under a vacuum atmosphere of atmospheric pressure 0.4 Pa into which 98% of argon gas and 2% of oxygen gas were introduced. did. In addition, the surface resistance value of the transparent conductive layer was 340 ohms / square.

Thereby, the transparent conductive film which consists of an anti blocking layer / transparent resin base material / hard-coat layer / optical adjustment layer / adhesion layer / transparent conductive layer was manufactured.

Example 2
A transparent conductive film was produced in the same manner as in Example 1 except that the composition of the adhesion composition was changed to the composition described in Table 1.

Comparative Examples 1 to 3
A transparent conductive film was produced in the same manner as in Example 1 except that the composition of the adhesion composition was changed to the composition described in Table 1.

Comparative example 4
A transparent conductive film was produced in the same manner as in Example 1 except that the adhesion layer was not provided.

Comparative example 5
A transparent conductive film was produced in the same manner as in Example 1 except that the hard coat layer was not provided.

(Measurement of element ratio of adhesion layer)
The surface element of the intermediate film (anti-blocking layer / transparent resin substrate / hard coat layer / optical adjustment layer / adhesive layer) at the time of forming the adhesive layer was subjected to X-ray photoelectron spectroscopy (ESCA) on the surface of the adhesive layer. An analysis was performed.

Specifically, after the cleaning (by SiO ₂ conversion: about 1 nm) by Ar ion etching was performed on the adhesion layer of the intermediate film, the qualitative analysis was performed by measuring by wide scan. Next, narrow scan measurement was performed on C, N, O, and Si elements to calculate an element ratio (atomic%). The measurement conditions were as follows.

Device: ULVAC-PHI, "Quantum 2000"
X-ray source: Monochrome Al K α
X-ray setting: 100 μmφ (15 kV, 25 W)
Photoelectron take-off angle: 45 degrees Neutralization condition: Combination of neutralization gun and Ar ion gun (neutralization mode) Acceleration voltage of Ar ion gun: 1 kV
Raster size of Ar ion gun: 2 mm x 2 mm
Etching rate of Ar ion gun: about 2 nm / min in terms of SiO ₂ The content ratio (atomic%) of the C element and the Si element, and the ratio thereof are shown in Table 1.

(Abrasion resistant)
An industrial wiper ("CONTEC, Inc.," Anticon, Gold Sorb ") is pressed against the surface of the transparent conductive layer of the transparent conductive film of each example and each comparative example to a load of 400 g in the range of φ11 mm. The slide was made 20 times between 10 cm in length. Then, to measure the orthogonal direction orthogonal to the sliding direction, arranged 4 Saguharishiki probe the transparent conductive layer was measured surface resistance value R ₂₀ of the transparent conductive film after sliding. Moreover, the surface resistance value of the said location before sliding was set to _R0 .

The case where the change rate R ₂₀ / R _{0 of the} surface resistance value was less than 1.20 was evaluated as 〇, and the case where it was 1.20 or more was evaluated as x. The results are shown in Table 1.

(Patterning characteristics)
A commercially available adhesive tape (1 cm wide) is attached in the form of stripes at intervals of 1 cm on the surface of the transparent conductive layer of the transparent conductive film of each example and each comparative example, and transparent using 50 wt. The conductive layer (ITO layer) was etched. Next, the pressure-sensitive adhesive tape was peeled off from the transparent conductive layer, and the surface of the exposed transparent conductive layer (pattern portion) was observed with a microscope (magnification: 20 times).

The case where the occurrence of a crack was not confirmed on the surface of the transparent conductive layer was evaluated as 〇, and the case where the occurrence of a crack was confirmed was evaluated as x. The results are shown in Table 1.

(appearance)
The transparent conductive films of Examples and Comparative Examples were observed with the naked eye.

In the case of a transparent conductive film, the case where no flaw was found at the time of production was evaluated as 〇, and the case where a flaw was confirmed was evaluated as x. The results are shown in Table 1.

(Flexibility)
The transparent conductive film was cut into a width of 50 mm and a length of 100 mm, folded in two so that the antiblocking layer was on the inside, and both ends in the lengthwise direction of the film were bonded with an adhesive tape to obtain Sample 10.

The disc-like weight 11 (diameter 50 mm, weight 500 g) was allowed to stand on the upper surface (width 50 mm × length 50 mm) of the sample 10 for 10 seconds, and then the bent portion 12 of the sample 10 was observed (see FIG. 3).

The case where breakage did not occur in the bent portion was evaluated as 、, and the breakage occurred in the bent portion, and the case where the film was split was evaluated as x. The results are shown in Table 1.

Although the above invention is provided as an exemplary embodiment of the present invention, this is merely an example and should not be interpreted in a limited manner. Variations of the invention that are apparent to those skilled in the art are within the scope of the following claims.

The transparent conductive film of the present invention can be applied to various industrial products, and is suitably used, for example, as a touch panel substrate provided in an image display device.

1 Transparent conductive film 3 Transparent resin base 4 Hard coat layer 5 Optical adjustment layer 6 Adhesion layer 7 Transparent conductive layer

Claims

A transparent resin substrate, a hard coat layer, an optical adjustment layer, an adhesive layer, and a transparent conductive layer in this order,
The adhesion layer is a resin layer containing nano silica particles,
The transparent conductive film, wherein the ratio of the number of silicon atoms to the number of carbon atoms is 0.50 or more on the surface on the transparent conductive layer side of the adhesive layer.
The ratio of the number of silicon atoms to the number of carbon atoms is 1.00 or more,
The transparent conductive film according to claim 1.
The thickness of the said contact | glue layer is 10 nm or more and 100 nm or less, The transparent conductive film of Claim 1 or 2 characterized by the above-mentioned.
The said transparent resin base material is a cycloolefin polymer film, The transparent conductive film of Claim 1 or 2 characterized by the above-mentioned.