KR20220025706A - transparent conductive film - Google Patents

Abstract

The transparent conductive film 1 is provided with the transparent base material 2, the cured resin layer 3, and the transparent conductive layer 4 in order. The cured resin layer 3 contains silica particles. The bending diameter measured by the flexibility test is 10 mm or less.

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.

DESCRIPTION OF RELATED ART Conventionally, the transparent conductive film which formed the transparent conductive layer which consists of indium tin composite oxide (ITO) in the desired electrode pattern is used for optical uses, such as a touchscreen.

The transparent conductive film may be required to have bending resistance depending on the purpose and use.

As such a transparent conductive film, a transparent conductive film having a transparent plastic film base material and a transparent conductive film sequentially provided and having a bending diameter of 10.7 mm according to a flexibility test has been proposed (see, for example, Example 7 of Patent Literature 1). .).

International Publication No. 2017/126466 pamphlet

In recent years, in order to respond to the display which has flexibility, such as a flexible display (foldable, bendable, rollable display, etc.), there exists a tendency for additional bending resistance to be calculated|required rather than the transparent conductive film of patent document 1.

An object of the present invention is to provide a transparent conductive film excellent in bending resistance.

The present invention [1] is provided with a transparent substrate, a cured resin layer, and a transparent conductive layer in this order, wherein the cured resin layer contains silica particles and has a bending diameter of 10 mm or less as measured by the following flexibility test, It contains a transparent conductive film.

Flexibility test: The transparent conductive film heat-treated at 165 degreeC for 75 minutes is cut into the rectangle of 20 mm x 80 mm. Next, connect the short side of the rectangle with a tester and observe the resistance value. The transparent conductive film was bent so that the short side of the rectangle came closer so that the transparent conductive layer was outside, and the warpage diameter (mm) of the transparent conductive film when the resistance value of the tester started to increase was measured.

The present invention [2] includes the transparent conductive film according to the above [1], wherein the thickness of the transparent conductive layer exceeds 35 nm.

This invention [3] contains the transparent conductive film as described in said [1] or [2] whose surface resistance value of the said transparent conductive layer is 45 ohms/square or less.

The present invention [4] includes the transparent conductive film according to any one of [1] to [3], wherein the thickness of the transparent substrate is 45 µm or less.

The transparent conductive film of this invention WHEREIN: The cured resin layer contains the silica particle.

Therefore, it is excellent in bending resistance.

Moreover, this transparent conductive film WHEREIN: The curvature diameter measured by the softness|flexibility test is 10 mm or less.

Therefore, it can be used suitably for the optical device and its component which are requested|required bending resistance.

1 : is sectional drawing of one Embodiment of the transparent conductive film of this invention.
FIG. 2 : shows sectional drawing of the modification (when a transparent conductive film is equipped with an optical adjustment layer) of the transparent conductive film shown in FIG. 1. FIG.
3 : shows sectional drawing of the modification (when a transparent conductive film is equipped with a hard-coat layer and an optical adjustment layer) of the transparent conductive film shown in FIG.

With reference to FIG. 1, one Embodiment of the transparent conductive film of this invention is described.

In FIG. 1 , the vertical direction in the paper is an up-down direction (thickness direction), and the upper side of the paper sheet is the upper side (one side in the thickness direction), and the lower side (the other side in the thickness direction) of the paper sheet is the lower side. In addition, the left-right direction and the depth direction of the paper are plane directions orthogonal to the up-down direction. Specifically, it is based on the direction arrows 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 plane direction orthogonal to the thickness direction, and has a flat upper surface and a flat lower surface. The transparent conductive film 1 is, for example, some parts, such as a base material for touch panels with which an image display apparatus is equipped, an electromagnetic wave shield, and is not an image display apparatus. That is, the transparent conductive film 1 is a component for manufacturing an image display apparatus etc., It distribute|circulates independently as a component, without including image display elements, such as an OLED module, It is a device usable industrially.

As specifically, shown in FIG. 1, the transparent conductive film 1 is equipped with the transparent base material 2, the cured resin layer 3, and the transparent conductive layer 4 toward the thickness direction one side in order. do. The transparent conductive film 1 is more specifically, the transparent base material 2, the cured resin layer 3 arrange|positioned on the upper surface (thickness direction one side) of the transparent base material 2, and the cured resin layer 3 The transparent conductive layer 4 is provided on the upper surface (thickness direction one side) of. Preferably, the transparent conductive film (1) is provided with only the transparent base material (2), the cured resin layer (3), and the transparent conductive layer (4).

The thickness of the transparent conductive film 1 is, for example, 200 µm or less, preferably 150 µm or less, and more preferably 100 µm or less.

2. Transparent substrate

The transparent substrate 2 is a transparent substrate for ensuring the mechanical strength of the transparent conductive film 1 .

The transparent base material 2 has a film shape. The transparent base material 2 is arrange|positioned on the whole lower surface of the cured resin layer 3 so that it may contact with the lower surface of the cured resin layer 3 .

The transparent substrate 2 is, for example, a polymer film having transparency. As a material of the transparent base material 2, For example, Polyethylene, polypropylene, olefin resins, such as a cycloolefin polymer, For example, Polyethylene terephthalate (PET), polybutylene terephthalate, poly, such as a polyethylene naphthalate Ester resins, for example, (meth)acrylic resins (acrylic resins and/or methacrylic resins) such as polymethacrylate, for example polycarbonate resins, polyethersulfone resins, polyarylate resins, melamine resins, Polyamide resin, polyimide resin, cellulose resin, polystyrene resin, etc. are mentioned, Preferably an olefin resin is mentioned, More preferably, a cycloolefin polymer is mentioned.

The thickness of the transparent base material 2 is, for example, 60 micrometers or less, Preferably it is 45 micrometers or less.

Flexural resistance can be improved as the thickness of the transparent base material 2 is below the said upper limit.

3. Cured resin layer

The cured resin layer 3 has a film shape. The cured resin layer 3 is disposed on the entire lower surface of the transparent conductive layer 4 so as to contact the lower surface of the cured resin layer 3 .

As the cured resin layer 3, the hard-coat layer 5 is mentioned.

In addition, in the following description, the case where the cured resin layer 3 is the hard-coat layer 5 is demonstrated.

The hard-coat layer 5 is a protective layer for suppressing that a flaw generate|occur|produces in the transparent base material 2, when manufacturing the transparent conductive film 1. Moreover, when the transparent conductive film 1 is laminated|stacked, the hard-coat layer 5 is an abrasion-resistant layer for suppressing that an abrasion generate|occur|produces in the transparent conductive layer 4 .

The hard-coat layer 5 is formed from a hard-coat composition.

A hard-coat composition contains resin and particle|grains.

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

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

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

As active energy ray-curable resin, specifically, (meth)acrylic-type ultraviolet curable resin, such as a urethane acrylate and an epoxy acrylate, is mentioned, for example.

Moreover, as curable resin other than active energy ray-curable resin, thermosetting resins, such as a urethane resin, a melamine resin, an alkyd resin, a siloxane type polymer, and an organosilane condensate, are mentioned, for example.

Resin can be used individually or in combination of 2 or more types.

Particles contain silica particles as an essential component.

That is, the hard-coat composition contains a silica particle. And the hard-coat layer 5 (cured resin layer 3) formed from such a hard-coat composition contains a silica particle.

When the hard-coat layer 5 (cured resin layer 3) contains a silica particle, bending resistance will improve.

Moreover, particle|grains contain other particle|grains other than a silica particle as an arbitrary component.

As other particle|grains, an inorganic particle (a silica particle is excluded.), an organic particle, etc. are mentioned, for example.

As inorganic particles (silica particles are excluded), for example, zirconia particles, for example, metal oxide particles made of zirconium oxide, titanium oxide, zinc oxide, tin oxide, etc. For example, carbonates such as calcium carbonate particles and the like.

As organic particle|grains, crosslinked acrylic resin particle|grains etc. are mentioned, for example.

The other particles are preferably inorganic particles (excluding silica particles), and more preferably zirconia particles.

Other particle|grains can be used individually or in combination of 2 or more types.

As described above, the particles include, as an essential component, silica particles and, as an optional component, other particles. The particles preferably include silica particles and other particles.

When the particles contain silica particles and other particles, bending resistance can be improved.

In addition, when the particles contain silica particles and other particles, the mixing ratio of the silica particles is, for example, 1 part by mass or more with respect to 100 parts by mass of the total amount of the silica particles and other particles, and, for example, For example, 10 parts by mass or less, preferably 5 parts by mass or less, the blending ratio of other particles is, for example, 90 parts by mass or more, preferably 95 parts by mass relative to 100 parts by mass of the total amount of silica particles and other particles. It is more than a part, and is 99 mass parts or less, for example.

And a hard-coat composition is obtained by mixing resin and particle|grains.

The compounding ratio of resin is, for example, 20 mass % or more with respect to a hard-coat composition, and is 40 mass % or less, for example.

Moreover, the compounding ratio of particle|grains is 50 mass % or more with respect to a hard-coat composition, and is 80 mass % or less, for example.

Moreover, well-known additives, such as a leveling agent, a thixotropic agent, and an antistatic agent, can be mix|blended with a hard-coat composition as needed.

In order to form the hard coat layer 5 (cured resin layer 3), as will be described later in detail, a diluent of the hard coat composition is applied to one side in the thickness direction of the transparent base material 2, dried, and then subjected to ultraviolet irradiation Thereby, an optical adjustment composition is hardened.

Thereby, the hard-coat layer 5 is formed.

The thickness of the hard coat layer 5 (cured resin layer 3) is, from the viewpoint of scratch resistance, for example, 0.1 µm or more, preferably 0.5 µm or more, and, for example, 10 µm or less, Preferably it is 3 micrometers or less. The thickness of the hard-coat layer 5 can be measured by cross-sectional observation using a transmission electron microscope, for example.

4. Transparent conductive layer

The transparent conductive layer 4 is crystalline and is a transparent layer which expresses the outstanding electroconductivity.

The transparent conductive layer 4 has a film shape. The transparent conductive layer 4 is arrange|positioned so that the upper surface (thickness direction one surface) whole surface of the cured resin layer 3 may contact with the thickness direction one surface of the cured resin layer 3 .

As the material of the transparent conductive layer 4, for example, In, Sn, Zn, Ga, Sb, Ti, Si, Zr, Mg, Al, Au, Ag, Cu, Pd, selected from the group consisting of W and metal oxides containing at least one metal. The metal oxide may be further doped with the metal atom shown in the said group as needed.

Specific examples of the transparent conductive layer 4 include indium-containing oxides such as indium tin composite oxide (ITO), and antimony-containing oxides such as antimony tin composite oxide (ATO). and preferably an indium-containing oxide, more preferably ITO.

When using ITO as the material of the transparent conductive layer 4, the content rate of tin oxide is, for example, 0.5 mass% or more, preferably 3 mass% or more, with respect to the total amount of tin oxide and indium oxide, more Preferably it is 5 mass % or more, More preferably, it is 8 mass % or more, Especially preferably, it is 9 mass % or more, For example, it is 20 mass % or less, Preferably it is 15 mass % or less.

Lowering resistance is accelerated|stimulated that the content rate of a tin oxide is more than the said lower limit. The transparent conductive layer 4 is excellent in intensity|strength as the content rate of a tin oxide is below the above-mentioned upper limit.

Moreover, the transparent conductive layer 4 can contain the area|region where the ratio of a tin oxide is 8 mass % or more. When the transparent conductive layer 4 contains the area|region where the ratio of a tin oxide is 8 mass % or more, a surface resistance value can be made small.

For example, as for the transparent conductive layer 4, the ratio of the tin oxide in the 1st area|region 11 as an example of the area|region where the ratio of tin oxide is 8 mass % or more, and the tin oxide in the 1st area|region 11 is lower than the tin oxide a second region 12 , which is the ratio of . Specifically, the transparent conductive layer 4 contains a layered 1st area|region and the layered 2nd area|region 12 arrange|positioned on one side of the thickness direction of the 1st area|region 11 in order. In addition, the boundary of the 1st area|region 11 and the 2nd area|region 12 is not confirmed by observation with a measuring apparatus, and a vague thing is allowed. Moreover, in this transparent conductive layer 4, you may have a density|concentration gradient in which a tin oxide density|concentration becomes high gradually toward the other side from one side in the thickness direction. When the transparent conductive layer 4 includes a second region in addition to the above-described first region, a desired crystallization rate can be obtained by adjusting the proportion of the region.

The proportion of tin oxide in the first region 11 is preferably 9 mass% or more, more preferably 10 mass% or more, and is 20 mass% or less.

The ratio of the thickness of the first region 11 to the thickness of the transparent conductive layer 4 is, for example, more than 50%, preferably 70% or more, more preferably 80% or more, still more preferably It is 90 % or more, and is 99 % or less, for example, Preferably it is 97 % or less.

The ratio of the tin oxide in the transparent conductive layer 4 can be made high that the ratio of the thickness of the 1st area|region 11 is more than the above-mentioned lower limit, Therefore, a surface resistance value can fully be lowered|hung.

The proportion of tin oxide in the second region 12 is, for example, less than 8 mass%, preferably 7 mass% or less, more preferably 5 mass% or less, still more preferably 4 mass% or less. , Also, for example, 1 mass% or more, preferably 2 mass% or more, more preferably 3 mass% or more.

The ratio of the thickness of the second region 12 to the thickness of the transparent conductive layer 4 is, for example, 1% or more, preferably 3% or more, and for example, 50% or less, preferably Preferably it is 30 % or less, More preferably, it is 20 % or less, More preferably, it is 10 % or less.

Ratio of the ratio of tin oxide in the first region to the ratio of tin oxide in the second region 12 (ratio of tin oxide in the first region/ratio of tin oxide in the second region) ) is, for example, 1.5 or more, preferably 2 or more, more preferably 2.5 or more, and for example, 5 or less, preferably 4 or less.

The tin oxide concentration in each of the transparent conductive layer 4, the 1st area|region 11, and the 2nd area|region 12 is measured by X-ray photoelectron spectroscopy. Or the content rate of a tin oxide can also be estimated from the component (it is already known) of the target used when forming the amorphous transparent conductive layer 4 by sputtering.

Moreover, the transparent conductive layer 4 is crystalline.

When the transparent conductive layer 4 is crystalline, the specific resistance mentioned later can be made small.

The crystallinity of the transparent conductive layer 4 is determined by, for example, immersing the transparent conductive film 1 in hydrochloric acid (20° C., concentration of 5 mass%) for 15 minutes, followed by washing with water and drying, after which the transparent conductive layer ( 4) It can be judged by measuring the resistance between terminals between about 15 mm with respect to the surface of the side. In the transparent conductive film 1 after immersion, washing with water, and drying, when the resistance between terminals between 15 mm is 10 kΩ or less, the transparent conductive layer 4 is crystalline, and on the other hand, the resistance exceeds 10 kΩ. In this case, the transparent conductive layer 4 is amorphous.

The thickness of the transparent conductive layer 4 is, for example, 20 nm or more, preferably 30 nm or more, more preferably more than 35 nm, still more preferably 40 nm or more, particularly preferably 50 nm or more, , and is, for example, 80 nm or less.

The surface resistance value of the transparent conductive layer 4 can be made small that the thickness of the transparent conductive layer 4 is more than the said minimum.

In addition, the thickness of the transparent conductive layer 4 can be measured by observing the cross section of the transparent conductive film 1 using a transmission electron microscope, for example.

The specific resistance of the transparent conductive layer 4 is, for example, 2.6 × 10 ^-4 Ω·cm or less, preferably 2.4 × 10 ^-4 Ω·cm or less, more preferably less than 2.2 × 10 ^-4 Ω·cm or less. , more preferably 2.1 × 10 ^-4 Ω·cm or less.

When the specific resistance of the transparent conductive layer 4 is below the above-described upper limit, when the transparent conductive layer 4 is patterned and used as an electrode, excellent electrical properties can be exhibited.

In addition, a specific resistance can be measured by the 4-probe method based on JISK7194.

The surface resistance value of the transparent conductive layer 4 is, for example, 120 Ω/□ or less, preferably 80 Ω/□ or less, more preferably 50 Ω/□ or less, still more preferably 45 Ω/□ or less. am.

When the surface resistance value of the transparent conductive layer 4 is below the above-mentioned upper limit, when patterning the transparent conductive layer 4 and using it as an electrode, the outstanding electrical property can be expressed.

The lower limit of the surface resistance value of the transparent conductive layer 4 is not specifically limited. For example, the surface resistance value of the transparent conductive layer 4 is more than 0 ohm/square and 1 ohm/square or more normally.

In addition, a surface resistance value can be measured by the 4-probe method based on JISK7194.

5. Manufacturing method of transparent conductive film

Next, the manufacturing method of the transparent conductive film 1 is demonstrated.

The method for producing the transparent conductive film 1 includes a first step of arranging the cured resin layer 3 on one side of the transparent base material 2 in the thickness direction, and a first step of arranging the cured resin layer 3 on one side of the cured resin layer 3 in the thickness direction, The second step of forming the amorphous transparent conductive layer 4 by sputtering and the third step of heating the amorphous transparent conductive layer 4 to form the crystalline transparent conductive layer 4 are provided. Moreover, in this manufacturing method, each layer is arrange|positioned one by one by a roll-to-roll system, for example.

At a 1st process, the transparent base material 2 is prepared first.

Next, the dilution liquid of a hard-coat composition is apply|coated to one side of the thickness direction of the transparent base material 2, and after drying, a hard-coat composition is hardened by ultraviolet irradiation. Thereby, the hard-coat layer 5 (cured resin layer 3) is formed in the thickness direction one side of the transparent base material 2.

At a 2nd process, the amorphous transparent conductive layer 4 is formed in the thickness direction one side of the hard-coat layer 5 (cured resin layer 3) by sputtering.

Sputtering is carried out in presence of an inert gas, specifically, in a sputtering apparatus, opposing the thickness direction one surface of the cured resin layer 3 to the target which consists of the material of the transparent conductive layer 4. At this time, in addition to the above-described inert gas, for example, a reactive gas such as oxygen may be present.

As an inert gas, noble gases, such as argon, etc. are mentioned, for example. The partial pressure of the inert gas in the sputtering apparatus is, for example, 0.1 Pa or more, preferably 0.3 Pa or more, and for example, 10 Pa or less, preferably 5 Pa or less, more preferably 1 Pa or less. is below. The energy of the atoms of the inert gas in sputtering becomes low that the partial pressure of an inert gas is more than the said lower limit. Then, it can suppress that the amorphous transparent conductive layer 4 introduce|transduces the atom of an inert gas.

The pressure in the sputtering apparatus is the total pressure of the partial pressure of the inert gas and the partial pressure of the reactive gas.

In addition, when using ITO as the material of the transparent conductive layer 4, the first target and the second target having different tin oxide concentrations are sequentially arranged along the conveyance direction of the transparent substrate 2 in the sputtering apparatus. may be The material of a 1st target is ITO (tin oxide concentration: 8 mass % or more) in the above-mentioned 1st area|region 11, for example. The material of the 2nd target is ITO (tin oxide concentration: less than 8 mass %) in the 2nd area|region 12 mentioned above, for example.

By said sputtering, the amorphous transparent conductive layer 4 is formed in the thickness direction one side of the transparent base material 2 .

In addition, when the amorphous transparent conductive layer 4 is formed by sputtering using the above-mentioned 1st target and 2nd target, the amorphous transparent conductive layer 4 is a tin oxide concentration different from each other. The first amorphous layer and the second amorphous layer are sequentially provided toward one side in the thickness direction. Each material of the first amorphous layer and the second amorphous layer is the same as that of the first target and the second target. Specifically, the tin oxide concentration in ITO of the first amorphous layer is, for example, 8 mass% or more. The tin oxide concentration in ITO of the 2nd amorphous layer is less than 8 mass %, for example.

The ratio of the thickness of the first amorphous layer to the thickness of the amorphous transparent conductive layer 4 is, for example, more than 50%, preferably 70% or more, more preferably 80% or more, still more preferably It is 90 % or more, and is 99 % or less, for example, Preferably it is 97 % or less.

The ratio of the thickness of the second amorphous layer to the thickness of the transparent conductive layer 4 is, for example, 1% or more, preferably 3% or more, and for example, 50% or less, preferably 30 % or less, More preferably, it is 20 % or less, More preferably, it is 10 % or less.

Thereby, the amorphous laminated|multilayer film which consists of the transparent base material 2 and the amorphous transparent conductive layer 4 are obtained.

Then, in a 3rd process, the amorphous laminated|multilayer film is heated. For example, the amorphous transparent conductive layer 4 is heated by heating apparatuses, such as an infrared heater and oven.

Heating conditions are not specifically limited. The heating temperature is, for example, 90°C or higher, preferably 110°C or higher, and for example, 160°C or lower, preferably 140°C or lower. The heating time is, for example, 30 minutes or longer, more preferably 60 minutes or longer, and for example, 5 hours or shorter, preferably 3 hours or shorter.

Thereby, as shown in FIG. 1, the amorphous transparent conductive layer 4 is crystallized, and the crystalline transparent conductive layer 4 is formed.

Further, when the amorphous transparent conductive layer 4 includes the first amorphous layer and the second amorphous layer, the crystalline transparent conductive layer 4 corresponds to each of the first amorphous layer and the second amorphous layer. and a first region 11 and a second region 12 .

Thereby, the transparent conductive film 1 provided with the transparent base material 2, the hard-coat layer 5 (cured resin layer 3), and the transparent conductive layer 4 in order is manufactured.

Then, this transparent conductive film 1 is patterned with the crystalline transparent conductive layer 4 by etching etc., for example. The patterned crystalline transparent conductive layer 4 is used for electrodes, such as a touch panel (touch sensor).

6. action effect

In the transparent conductive film 1, the cured resin layer 3 (hard coat layer 5) contains silica particles.

Therefore, it can be estimated that the adhesiveness of the cured resin layer 3 and the transparent conductive layer 4 improves, and as a result, bending resistance improves.

Specifically, the bending diameter measured by the flexibility test described in detail in Examples to be described later is 10 mm or less, preferably 8 mm or less, more preferably 6 mm or less, still more preferably 4 mm or less, particularly Preferably it is less than or equal to 2 mm, most preferably less than 2 mm.

Since the transparent conductive film 1 has excellent bending resistance, it can be suitably used for optical devices and components thereof requiring bending resistance, such as flexible displays (foldable, bendable, rollable, etc.), for example. there is.

Moreover, from a viewpoint of making a surface resistance value low, there exists a case where the thickness of the transparent conductive layer 4 is enlarged (for example, 20 nm or more, Preferably it is 30 nm or more, More preferably, it exceeds 35 nm). . When the thickness of the transparent conductive layer 4 is enlarged, bending resistance may fall.

However, since the transparent conductive film 1 has excellent bending resistance, even if the thickness of the transparent conductive layer 4 is large, the bending diameter measured by the flexibility test described in detail can be made into the above-mentioned range. Therefore, it can be used suitably for the optical device and its component which are calculated|required both of bending resistance and a low surface resistance value.

7. Variations

In a modified example, about the same member and process as one Embodiment, the same reference numeral is attached|subjected, and the detailed description is abbreviate|omitted. In addition, the modified example can exhibit the effect similar to one Embodiment other than mentioning specifically. Moreover, one embodiment and its modification can be combined suitably.

The transparent conductive layer 4 may contain only the 1st area|region where the ratio of a tin oxide is 8 mass % or more, without including the 2nd area|region whose ratio of a tin oxide is less than 8 mass %.

Although the above description demonstrated the case where the cured resin layer 3 was the hard-coat layer 5, the optical adjustment layer 6 may be sufficient as the cured resin layer 3 as shown in FIG.

In such a case, the transparent conductive film 1 is equipped with the transparent base material 2, the optical adjustment layer 6 (cured resin layer 3), and the transparent conductive layer 4 in order.

The optical adjustment layer 6 suppresses the pattern recognition of the transparent conductive layer 4 or suppresses reflection at the interface in the transparent conductive film 1, and in order to ensure the transparency excellent in the transparent conductive film 1, It is a layer which adjusts the optical property (for example, refractive index) of the transparent conductive film (1).

The optical adjustment layer 6 is formed from an optical adjustment composition, for example.

The optical adjustment composition contains said resin and said particle|grains.

As resin, resin illustrated by the hard-coat composition is mentioned, Preferably (meth)acrylic-type ultraviolet curable resin is mentioned.

As described above, the particles contain, as an essential component, silica particles.

That is, the optical adjustment composition contains a silica particle. And the optical adjustment layer 6 (cured resin layer 3) formed from such an optical adjustment composition contains a silica particle.

When the optical adjustment layer 6 (hardened resin layer 3) contains a silica particle, bending resistance will improve.

Moreover, as above-mentioned, particle|grains contain other particle|grains as an arbitrary component.

As other particle|grains, the other particle|grains illustrated by the hard-coat composition are mentioned, Preferably it is a viewpoint of a refractive index, Preferably zirconium oxide is mentioned.

In addition, when the particles contain silica particles and other particles, the mixing ratio of the silica particles is, for example, 1 part by mass or more with respect to 100 parts by mass of the total amount of the silica particles and other particles, and, for example, For example, 10 parts by mass or less, preferably 5 parts by mass or less, the blending ratio of other particles is, for example, 90 parts by mass or more, preferably 95 parts by mass relative to 100 parts by mass of the total amount of silica particles and other particles. It is more than a part, and is 99 mass parts or less, for example.

And the optical adjustment composition is obtained by mixing resin and particle|grains.

The compounding ratio of resin is, for example, 20 mass % or more with respect to an optical adjustment composition, and is 40 mass % or less, for example.

Moreover, the compounding ratio of particle|grains is 50 mass % or more with respect to an optical adjustment composition, and is 80 mass % or less, for example.

The optical adjustment composition can further contain well-known additives, such as a leveling agent, a thixotropic agent, and an antistatic agent.

In order to form the optical adjustment layer 6 (cured resin layer 3), the dilution liquid of the optical adjustment composition is apply|coated to one side of the thickness direction of the transparent base material 2, and after drying, the optical adjustment composition is irradiated with ultraviolet rays. harden

Thereby, the optical adjustment layer 6 is formed.

The thickness of the optical adjustment layer 6 is, from a viewpoint of abrasion resistance, for example, 0.1 micrometer or more, Preferably, it is 0.5 micrometer or more, and, for example, is 10 micrometers or less, Preferably, it is 3 micrometers or less.

The thickness of the optical adjustment layer 6 can be measured by cross-sectional observation using a transmission electron microscope, for example.

Moreover, the transparent conductive film 1 may be equipped with both the hard-coat layer 5 and the optical adjustment layer 6 .

In such a case, as shown in FIG. 3, the transparent conductive film 1 comprises the transparent base material 2, the hard-coat layer 5, the optical adjustment layer 6, and the transparent conductive layer 4 provided in turn. In other words, the transparent conductive film 1 is provided with the transparent base material 2, the cured resin layer 3, and the transparent conductive layer 4 in order.

Moreover, an anti-blocking layer can also be arrange|positioned in the thickness direction other surface of the transparent base material 2.

In such a case, the transparent conductive film 1 is equipped with the anti-blocking layer, the transparent base material 2, the cured resin layer 3, and the transparent conductive layer 4 in order.

The anti-blocking layer imparts blocking resistance to the respective surfaces of the plurality of transparent conductive films 1 in contact with each other when the transparent conductive films 1 are laminated in the thickness direction or the like.

The anti-blocking layer has a film shape.

The material of the anti-blocking layer is, for example, an anti-blocking composition.

As an anti-blocking composition, the mixture etc. of Unexamined-Japanese-Patent No. 2016-179686 are mentioned, for example.

The thickness of the anti-blocking layer is, for example, 0.1 µm or more, and is, for example, 10 µm or less.

Example

Examples and comparative examples are shown below, and the present invention will be described more specifically. In addition, this invention is not limited to an Example and a comparative example at all. In addition, specific numerical values such as the blending ratio (content ratio), physical property values, and parameters used in the description below are described in the above "Mode for carrying out the invention" and corresponding blending ratios (content ratio) ), physical property values, parameters, etc., may be substituted with the upper limit (the numerical value defined as “less than” or “less than”) or the lower limit (the numerical value defined as “more than” or “exceed”) of the description.

1. Preparation of transparent conductive film

Example 1

First, as a transparent base material, the transparent film (43 micrometers in thickness) which consists of a cycloolefin resin was prepared.

Next, a dilution solution of a hard coat composition containing 65.5 parts by mass of zirconia particles, 2.5 parts by mass of silica particles and 32 parts by mass of an ultraviolet curable resin (acrylic resin) is applied to one surface in the thickness direction of the transparent film, and then dried , UV was irradiated to one side of the transparent film in the thickness direction to cure the hard coat composition. Thereby, the 0.7-micrometer-thick hard-coat layer was formed in one side of the transparent film.

Then, the 55-nm-thick amorphous transparent conductive layer was formed in the thickness direction one side of a hard-coat layer by sputtering.

Specifically, first, a first target made of ITO having a tin oxide concentration of 10% by weight and a second target made of ITO having a tin oxide concentration of 3.3% by weight are placed in a sputtering apparatus on the upstream side in the transport direction of the transparent film substrate They were arranged sequentially from the downstream side. Then, sputtering was carried out so that the ratio of the thickness of the first amorphous layer in the amorphous transparent conductive layer and the ratio of the thickness of the second amorphous layer were 95% and 5%, respectively. In addition, the amorphous transparent conductive layer contains a 1st amorphous layer (tin oxide concentration 10 mass %) and a 2nd amorphous layer (tin oxide concentration 3.3 mass %) sequentially toward one side in thickness direction.

By adjusting the argon flow rate at the time of sputtering, the argon partial pressure in a sputtering apparatus was adjusted to 0.35 Pa. In addition, the pressure in a sputtering apparatus was 0.42 Pa.

Thereby, the amorphous laminated|multilayer film provided with a transparent film, a hard-coat layer, and an amorphous transparent conductive layer in order was manufactured.

Then, the amorphous laminated|multilayer film was heated at 130 degreeC for 90 minutes, the amorphous transparent conductive layer was crystallized, and the crystalline transparent conductive layer was prepared.

Accordingly, a transparent conductive film including a transparent film, a hard coat layer, and a crystalline transparent conductive layer was prepared.

Moreover, the crystalline transparent conductive layer contained the 1st area|region and 2nd area|region resulting from each of the 1st amorphous layer and the 2nd amorphous layer.

Example 2, Example 3 and Comparative Example 1

A transparent conductive film was manufactured in the same manner as in Example 1 except that the thickness of the transparent substrate, the formulation of the hard coat composition, and the thickness of the transparent conductive layer were changed according to the description in Table 1.

2. Evaluation

(surface resistance)

Based on JISK7194, the surface resistivity of the transparent conductive layer of each Example and each comparative example was measured by the four-terminal method. The results are shown in Table 1.

(Flexibility Resistance)

About each Example and each comparative example, the transparent conductive film heat-processed at 165 degreeC for 75 minutes was cut into the rectangle of 20 mm x 80 mm. Next, connect the short side of the rectangle with a tester to observe the resistance value, and bend the transparent conductive film so that the transparent conductive layer is on the outside, and the short side of the rectangle is close to the side, and when the resistance value of the tester starts to increase The warpage diameter (mm) of the transparent conductive film was measured. The results are shown in Table 1.

In addition, although the said invention was provided as an exemplary embodiment of this invention, this is only a mere illustration and should not be interpreted limitedly. Modifications of the present invention that are obvious to those skilled in the art are included in the following claims.

Industrial Applicability

The transparent conductive film of this invention is used suitably in an optical use.

1: Transparent conductive film
2: Transparent substrate
3: cured resin layer
4: Transparent conductive layer

Claims (4)

A transparent base material, a cured resin layer, and a transparent conductive layer are sequentially provided,
The cured resin layer contains silica particles,
A transparent conductive film, characterized in that the warpage diameter measured by the following flexibility test is 10 mm or less.
Flexibility test: The transparent conductive film heat-treated at 165 degreeC for 75 minutes is cut into the rectangle of 20 mm x 80 mm. Next, connect the short side of the rectangle with a tester and observe the resistance value. The transparent conductive film was bent so that the short side of the rectangle came closer so that the transparent conductive layer was outside, and the warpage diameter (mm) of the transparent conductive film when the resistance value of the tester started to increase was measured. The method of claim 1,
The thickness of the said transparent conductive layer exceeds 35 nm, The transparent conductive film characterized by the above-mentioned. The method of claim 1,
The transparent conductive film is characterized in that the surface resistance value of the transparent conductive layer is 45 Ω/□ or less. The method of claim 1,
The thickness of the transparent base material is 45 micrometers or less, The transparent conductive film characterized by the above-mentioned.

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