JPH11138685A - Manufacture of transparent conductive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method for a transparent conductive sheet advantageous industrially for providing the required interlaminate bonding properties securely in the layer constitution of an optically isotropic base film having active energy ray curing type resin cured material layer [/an inorganic thin layer]/a transparent conductive layer is included ([ ] can be omitted.). SOLUTION: A transparent conductive sheet with a transparent conductive layer 4 formed through an inorganic thin layer 3 is provided on an active energy ray curing type resin coated material layer 2 of a polymer film having the layer constitution of forming the active energy ray cutting type resin curd material layer 2 formed at least on one face of an optically isotropic base film 1. At that time, a composition formed by blending the double bond of radial reaction properties and a monomer (b) having at least one kind of radical selected out of a group formed of epoxy, hydroxy, isocyanate and alkoxysilane with active energy ray curing type resin (a) is used as a resin liquid for forming the active energy ray curing type cured material layer 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a transparent conductive sheet suitable for an inner touch panel, a liquid crystal display device (including a ferroelectric polymer liquid crystal display device), and the like. .

[0002]

2. Description of the Related Art A transparent conductive sheet used for a transparent touch panel is basically composed of a conductive layer (in particular, an ITO layer).
/ When used as a touch panel having a layer structure of a polymer film, the conductive layer sides of two transparent conductive sheets are disposed so as to face each other via a spacer. One of the transparent conductive sheets arranged to face each other may be glass with a transparent conductive layer.

Recently, the development of a touch panel (inner touch panel) which is used so as to be superimposed below a polarizing plate of a liquid crystal display element has been developed. "Monthly Display" 19
On pages 50-54 of the January 1997 issue, a description of a touch panel (inner touch panel) superimposed under a polarizing plate, together with a conventional general touch panel provided on the front side of a liquid crystal display element (above the polarizing plate) Articles are published. The inner touch panel not only prevents light from being scattered and reflected by the air layer, but also allows the light coming out of the liquid crystal display element to be polarized and aligned before finally entering the human eye. In addition, the visibility is significantly improved, which is advantageous as compared with a conventional touch panel.

Japanese Patent Application Laid-Open No. 8-161 filed by the present applicant
No. 116 discloses a non-solvent type active energy ray-curable resin cured material layer on at least one surface of a photo-isotropic base film as a transparent conductive sheet for an inner touch panel, Transparent touch panel having a configuration in which a transparent conductive layer is further provided from above the material layer, and wherein the refractive index of the base film and the refractive index of the active energy ray-curable resin cured material layer satisfy a specific relationship. A transparent conductive sheet for use is shown.

[0005] Japanese Patent Application Laid-Open No. Hei 8-
No. 155,988 discloses a non-solvent type active energy ray-curable resin cured layer on both surfaces of a photo-isotropic base film as a transparent conductive sheet for an inner touch panel, and one of the active energy ray-curable resins. The surface of the cured product layer is formed as a convex and rough surface having fine and smooth hemispherical ridges, and the other active energy ray-curable resin cured product layer is further provided with a transparent conductive layer. An adhesive sheet is shown.

As disclosed in JP-A-8-161116 and JP-A-8-155988, providing an active energy ray-curable resin cured material layer on an optically isotropic substrate film is difficult in terms of rigidity (rigidity) and hardness. , Heat resistance, solvent resistance, scratch resistance, moisture permeability, surface condition, and the like.

[0007]

SUMMARY OF THE INVENTION As described above,
The transparent conductive sheet for an inner touch panel disclosed in JP-A-161116 and JP-A-8-155988 is provided with an active energy ray-curable resin cured material layer on at least one surface (preferably both surfaces) of an optically isotropic substrate film. A transparent conductive layer is provided on the active energy ray-curable resin cured product layer. In this case, if a transparent conductive layer is provided directly on the active energy ray-curable resin cured material layer, the adhesion of the transparent conductive layer may be insufficient. It is preferable to provide a layer, and to provide a transparent conductive layer thereon. That is, a typical layer configuration of the transparent conductive sheet for the inner touch panel is as follows: active energy ray-curable resin cured layer / optically isotropic substrate film / active energy ray-curable resin cured layer /
Inorganic thin layer / transparent conductive layer.

However, in this transparent conductive sheet for an inner touch panel, the adhesiveness between the optically isotropic substrate film and the active energy ray-curable resin cured material layer, the active energy ray-curable resin cured material layer, And / or adhesion between the inorganic thin layer and the inorganic thin layer. When such a shortage of adhesion occurs, delamination occurs when keying and pen input operations are repeated,
This leads to a shortened touch panel life.

The above-described insufficient adhesion is likely to occur when a transparent conductive sheet having a similar laminated structure is used as a transparent conductive sheet for a ferroelectric polymer liquid crystal display device. Also, when used as a transparent conductive sheet of a liquid crystal cell of a normal liquid crystal display element, it is required that the adhesion is not insufficient.

Under such a background, the present invention provides a transparent conductive sheet having a layer structure of a photoisotropic base film / active energy ray-curable resin cured layer [/ inorganic thin layer] / transparent conductive layer. [] Can be omitted), and an object of the present invention is to provide an industrially advantageous method for producing a transparent conductive sheet capable of reliably obtaining necessary interlayer adhesion.

[0011]

According to the method for producing a transparent conductive sheet of the present invention, an active energy ray-curable resin cured material layer (2) is provided on at least one surface of a photoisotropic substrate film (1). A transparent conductive sheet having a transparent conductive layer (4) provided directly or via an inorganic thin layer (3) on an active energy ray-curable resin cured product layer (2) of a polymer film having a layer structure is obtained. In this regard, as a resin liquid for forming the active energy ray-curable resin cured product layer (2), the active energy ray-curable resin (a) has a radically reactive double bond and an epoxy group, a hydroxyl group, an isocyanate group and A composition comprising a monomer (b) having at least one group selected from the group consisting of alkoxysilane groups is used.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

<Optically Isotropic Substrate Film (1)> As the optically isotropic substrate film (1), films such as polycarbonate, polyarylate, polyether sulfone, polysulfone, and amorphous polyolefin (norbornene resin) are used. The polycarbonate film is important. The thickness of the optically isotropic substrate film (1) is not limited, but is usually 20 to 250 μm, preferably 50 to 18 μm.
It is often 0 μm.

The optically isotropic substrate film (1) can be produced by an extrusion method, but a film obtained by a casting method is preferable in consideration of optical isotropic properties, film properties and the like.

The optically isotropic substrate film (1) has a retardation value of 30 nm or less (preferably 20 nm or less, more preferably 15 nm or less) and a visible light transmittance at 550 nm of 70% or more (preferably 80% or more). It is particularly desirable that the glass transition point is 100 ° C. or higher. When the retardation value exceeds 30 nm, optical isotropy is lost to cause coloring and interference light, and the amount of light reflection increases, and the visibility of an image decreases. If the visible light transmittance is less than 70%, the brightness when used for a touch panel or the like is insufficient. When the glass transition point is lower than 100 ° C., the heat resistance in the printing process becomes insufficient.

<Active energy ray-curable resin cured material layer>
(2)> An active energy ray-curable resin cured material layer (2) layer is provided on at least one surface, preferably both surfaces, of the optically isotropic substrate film (1). The thickness of the active energy ray-curable resin cured material layer (2) is not particularly limited.
１００100 μm, especially 5-50 μm.

In the present invention, as the resin liquid for forming the active energy ray-curable resin cured product layer (2), the active energy ray-curable resin (a) is prepared by adding a radical-reactive double bond and an epoxy group. And a monomer (b) having at least one group selected from the group consisting of a hydroxyl group, an isocyanate group and an alkoxysilane group.

First, as the active energy ray-curable resin (a), silicone acrylate, epoxy acrylate, acrylic acrylate, and the like are used in consideration of stiffness (rigidity), hardness, heat resistance, solvent resistance, scratch resistance, and moisture permeability. An ester or urethane acrylate-based active energy ray-curable resin (photopolymerizable prepolymer) is preferably used.

As the monomer (b), a monomer having a double bond having radical reactivity and at least one group selected from the group consisting of an epoxy group, a hydroxyl group, an isocyanate group and an alkoxysilane group is used. The alkoxysilane group is a methoxysilane group or an ethoxysilane group. An example of such a monomer (b) is a compound represented by the following formula.

[0020]

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[0021]

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[0022]

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[0023]

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The proportion of the monomer (b) to 100 parts by weight of the active energy ray-curable resin (a) is preferably 0.01 to 15 parts by weight, particularly preferably 0.5 to 10 parts by weight. When the proportion of the monomer (b) is too small, the effect of improving the adhesion is insufficient, and when the proportion of the monomer (b) is too large, the balance may be lost in terms of physical properties or the formed layer may be whitened. .

Active energy ray-curable resin cured layer (2)
In addition, a reactive diluent may be added to the resin solution for forming. Examples of the reactive diluent include monofunctional monomers such as 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and 2-hydroxypropyl (meth) acrylate; 1,3-butanediol di (meth) acrylate; 1,4-butanediol di (meth) acrylate, 1,6-hexadiol di (meth) acrylate, diethylene glycol di (meth) acrylate, neopentyl glycol di (meth)
Bifunctional monomers such as acrylate and polyethylene glycol di (meth) acrylate; trifunctional or higher such as trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, triallyl isocyanurate And other photopolymerizable monomers. The mixing ratio of the reactive diluent to 100 parts by weight of the active energy ray-curable resin (a)
It is about 60 parts by weight.

When the active energy ray-curable resin (a) is an ultraviolet-curable resin, it is usual to add a photoinitiator to the resin liquid. As the photoinitiator, acetophenones, benzophenones, Michler's ketone, benzyl, benzoin, benzoin ether, benzyldimethyl ketal, thioxanthone, any photoinitiator known as a photoinitiator of ultraviolet curable resin is used Can be The mixing ratio of the photoinitiator to 100 parts by weight of the ultraviolet curable resin (a) is, for example, about 0.1 to 8 parts by weight.
A sensitizer can be used together with the photoinitiator.

The active energy ray-curable resin cured material layer (2) is formed on the optically isotropic substrate film (1) by a pair of rolls arranged in parallel with a slight gap therebetween. (1) and the mold film (M) are supplied, and the resin liquid composed of the above composition is discharged toward the gap between the rolls, and the two rolls are rotated in a direction to bite each other to form the optically isotropic base film. The resin liquid is sandwiched between (1) and the mold film (M), and the resin liquid is cured by irradiating or heating with active energy rays (ultraviolet rays or electron beams) in such a state. It is particularly desirable to employ a method. After irradiation with active energy rays, heat treatment may be further performed as necessary to complete the curing.

When forming the active energy ray-curable resin cured material layer (2) on both surfaces of the optically isotropic substrate film (1),
The same operation may be performed using the laminated film of the photoisotropic substrate film (1) / active energy ray-curable resin cured product layer (2) obtained as described above and the mold film (M). . As a result, a polymer film having the layer structure of the active energy ray-curable resin cured product layer (2) / optically isotropic substrate film (1) / active energy ray-curable resin cured product layer (2) is obtained.

The above mold film (M) is peeled off at an appropriate stage. Here, as the mold film (M), a biaxially oriented polyester film, a biaxially oriented polypropylene film, or the like is suitably used. When these films are used as the mold film (M), the mold film (M) can be smoothly peeled at an appropriate stage after the formation of the active energy ray-curable resin cured product layer (2).

Active energy ray-curable resin cured product layer (2)
Can also be achieved by coating the above-mentioned resin liquid on the optically isotropic substrate film (1) and then irradiating it with active energy rays. However, the active energy ray-curable resin cured material layer (2) on the optically isotropic substrate film (1) using the mold film (M) as described above
When the method of forming is adopted, the film thickness accuracy is improved, and
Such a trouble does not occur even if a resin liquid which absorbs moisture in the air and easily causes cloudiness, such as silicone acrylate, is used as the resin liquid. Therefore, it is industrially advantageous as compared with the case where the active energy ray-curable resin cured product layer (2) is formed by a coating method.

Active energy ray-curable resin cured product layer (2)
Can be formed smoothly or on a fine uneven surface. If the mold film (M) mentioned above has a smooth surface or a film with fine irregularities, it can easily be used as an active energy ray-curable resin cured product layer.
The surface of (2) can be formed into a smooth or fine uneven surface.

<Other layers> The optically isotropic substrate film (1) and the active energy ray-curable resin cured layer (2) described above.
In addition, if necessary, an air-permeable resin layer or a thermosetting resin layer can be added. One example of the air-permeable resin layer is a vinyl alcohol-based polymer (including a copolymer, a graft copolymer, and a coexisting polymer, and also including a combination with a crosslinking agent).
Layer. One example of the thermosetting resin layer is a phenoxy ether type thermosetting resin layer.

<Inorganic thin layer (3)> Optically isotropic base film
On the active energy ray-curable resin cured product layer (2) of the polymer film having a layer configuration in which the active energy ray-curable resin cured layer (2) layer is provided on at least one surface of (1),
Usually, an inorganic thin layer (3) is provided. However, the inorganic thin layer (3) may be omitted.

Examples of the inorganic thin layer (3) include metal oxides, metal nitrides, metal borides, and the like, and may be a composite of two or more kinds. This inorganic thin layer (3) is moisture-proof,
Heat resistance, air resistance, acid / alkali resistance, transparent conductive layer (4)
This is advantageous in terms of adhesion and the like. The inorganic thin layer (3) is usually formed by a sputtering method. Inorganic thin layer (3)
Has a thickness of 20 to 300 angstroms, especially 30 to 300 angstroms.
180 Å is suitable.

<Transparent conductive layer (4)> A transparent conductive layer (4) is provided on the inorganic thin layer (3) (although the inorganic thin layer (3) may be omitted in some cases). Transparent conductive layer
(4) ITO, InO ₂ , SnO ₂ , ZnO,
Layers such as Au, Ag, Pt, and Pd.
O is important. The transparent conductive layer (4) is preferably formed by a sputtering method, but it is also possible to employ a vacuum evaporation method, an ion plating method, a sol-gel method, a coating method, or the like.

The thickness of the transparent conductive layer (4) is, for example, 100 to 2000 angstroms, particularly 150 to 1000 angstroms, for example, when ITO is used as an example.

The transparent conductive layer (4) is used as a whole-surface electrode or as a pattern electrode by forming a resist and etching after forming the whole-surface electrode.

<Transparent conductive sheet>
(2) / (3) / (4), (2) / (1) / (2) / (3) / (4), (3) / (2) / (1) /
A transparent conductive sheet having a layer configuration such as (2) / (3) / (4) is obtained. In special cases, (4) is provided on both sides (4) /
A layer configuration such as (3) / (2) / (1) / (2) / (3) / (4) can also be used. However, in the above layer configuration, there may be an embodiment in which at least one layer (3) is omitted.

<Other Adhesion-Improving Treatments> In the present invention, the adhesion is improved in terms of the composition of the active energy ray-curable resin cured layer (2). On the active energy ray-curable resin cured material layer (2) installation side of the material film (1) and / or on the inorganic thin layer (3) installation side of the active energy ray-curable resin cured material layer (2) Prior to the application of these layers (2) or (3) on the surface, treatment such as organic chemical treatment, corona discharge treatment, ultraviolet irradiation treatment in the presence or absence of ozone, low-temperature plasma treatment, formation of anchor coating layer, etc. An adhesion improving treatment may be performed.

<Use of transparent conductive sheet> The transparent conductive sheet thus obtained is used for an inner touch panel which is used under a polarizing plate of a liquid crystal display element or for a ferroelectric polymer liquid crystal. It is particularly useful as a transparent conductive sheet for a display element. Further, it can be used as a transparent conductive sheet of a liquid crystal cell of a normal liquid crystal display element.

When manufacturing the inner touch panel,
Typically, the above-mentioned transparent conductive sheet and a counterpart transparent conductive sheet (including glass) are made to face each other with the transparent conductive layer (4) side of the two sheets facing each other, and between the two sheets, for example, A dot spacer having a thickness of about 0.02 to 1.0 mm may be interposed. The other transparent conductive sheet may be a transparent conductive sheet having the same layer configuration as described above, another suitable transparent conductive sheet, or glass with a transparent electrode. That is, in the present invention, the above-described transparent conductive sheet is used as at least one of the two transparent conductive sheets facing each other. The inner touch panel obtained in this manner is adhered under a polarizing plate on the incident light side of the liquid crystal display element using an adhesive or the like.

When a ferroelectric polymer liquid crystal display device is manufactured, typically, the above-mentioned transparent conductive sheet and a counterpart transparent conductive sheet (including glass) are combined with each other. It suffices that the transparent conductive layer (4) side is made to face and a ferroelectric polymer liquid crystal layer is interposed between both sheets.

When a normal liquid crystal display element is manufactured, typically, the above-mentioned transparent conductive sheet and a counterpart transparent conductive sheet (including glass) are combined with the transparent conductive layer of the two sheets. (4) A liquid crystal cell may be manufactured by facing the sides and sealing liquid crystal between both sheets.

[0044]

The present invention will be further described with reference to the following examples. Hereinafter, "parts" means parts by weight.

Examples 1-4, Comparative Example 1 A thickness of 100 μm, which is an example of the optically isotropic substrate film (1)
Was prepared.

Active energy ray-curable resin cured product layer (2)
Active energy ray-curable resin
As an example of (a), 100 parts of a urethane acrylate-based UV-curable resin is mixed with 5 parts of the monomer (b) represented by the above formula (1), (2), (3) or (4), and acetophenone. Four types of compositions were prepared by blending 3 parts of a system photoinitiator. The monomer (b) used was (1) manufactured by Nippon Kayaku Co., Ltd.
YARAD R-128H '', (2) CYCLOMER A-200 manufactured by Daicel Chemical Industries, Ltd., (3) Shin-Etsu Silicone Co., Ltd. silane coupling agent `` KBM-503 '', (4) Showa Denko It is "Karenz MOI" manufactured by Co., Ltd. For comparison, a resin solution containing no monomer (b) was also prepared.

A resin liquid comprising the above composition is coated on the above-mentioned optically isotropic substrate film (1), and is cured by irradiation with ultraviolet rays (integrated light amount of 1000 mJ / cm ² ) to form a 12 μm-thick active energy ray ( An ultraviolet (UV) curable resin layer (2) was formed and heat-treated at 120 ° C. for 10 minutes.

Next, a 90 angstrom thick SiO ₂ layer as an example of the inorganic thin layer (3) was formed on the curable resin cured product layer (2) of the obtained laminated film. Was sputtered to form a transparent conductive layer (4) having a thickness of 500 angstroms.

The surfaces of the ITO were adhered to each other with a thermosetting sealant that adheres to the ITO layer, and the thermosetting sealant was cured at 120 ° C. for 60 minutes. (90 ° peeling, width 25.4m)
m, tensile speed 5 mm / min, length 15 mm), the peel strength at the interface between the cured resin layer (2) and the inorganic thin layer (3) was measured (n = 5). Table 1 shows the results.

[0050]

[Table 1] Type of peel strength monomer (b) (gf / inch) Comparative Example 1 Not used 117 Example 1 (1) Double bond and hydroxyl group contained 312 Example 2 (2) Double bond and epoxy group contained 349 Example 3 (3) Double bond and alkoxysilane group-containing 409 Example 4 (4) Double bond and isocyanate group-containing 438

From Table 1, as the resin liquid for forming the active energy ray-curable resin cured material layer (2), a composition in which a specific amount of a specific monomer (b) was added to the active energy ray-curable resin (a) was used. It can be seen that by using this, the adhesive strength (peel strength) at the interface between the active energy ray-curable resin cured material layer (2) and the inorganic thin layer (3) is surely improved.

When each of polyarylate, polyethersulfone, polysulfone, and amorphous polyolefin films was used in place of the polycarbonate film, the same adhesive strength (peel strength) was significantly improved.
And it was confirmed that the transparency did not change.

Example 5 and Comparative Example 2 FIG. 1 is a schematic sectional view showing an example of a transparent conductive sheet obtained by the method of the present invention.

As an example of the optically isotropic substrate film (1),
A 100 μm thick film obtained by casting a polycarbonate film was prepared. The retardation value is 4 nm, 55
The visible light transmittance at 0 nm is 90%, and the glass transition point is 13%.
5 ° C.

As the mold film (M), a thickness of 100 μm
And a smooth transparent polyester film having a thickness of 100 μm.

The above-mentioned optically isotropic substrate film (1) and the above-mentioned matted mold film (M) are supplied to a pair of rolls arranged in parallel with a slight gap therebetween, and the gap is provided between the rolls. Aiming at 100 parts of a non-solvent type urethane acrylate-based UV-curable resin (a), a monomer (b) 5 represented by the above formula (1), (2), (3) or (4) is added.
Part and a benzophenone-based photoinitiator, 5 parts of a resin liquid is discharged, and at the same time, both rolls are rotated in the direction of biting each other to form a photoisotropic base film (1).
And the mold film (M) so that the resin liquid is sandwiched therebetween.
UV rays are irradiated under the condition of / cm ² to cure the resin liquid, so that active energy rays (UV) having a thickness of 12 μm
The cured resin layer (2) was formed, and heat treatment was further performed at 120 ° C. for 10 minutes.

Subsequently, the above-obtained laminated film having the layer structure of (1) / (2) / (M) and the above-mentioned smooth mold were placed on a pair of rolls arranged in parallel with a slight gap. Film (M)
To supply the isotropic substrate film of the laminated film (1)
The same resin liquid as above is discharged between the side and the mold film (M), and both rolls are rotated in a direction to bite each other, so that the resin liquid flows between the laminated film and the mold film (M). An active energy ray (ultraviolet ray) curable resin having a thickness of 13 μm is cured by irradiating ultraviolet rays under the condition of an integrated light quantity of 1000 mJ / cm ² to cure the resin liquid. Then, heat treatment was performed at a temperature of 120 ° C. for 10 minutes.

As a result, a laminated film having a layer structure of (M) / (2) / (1) / (2) / (M) was obtained. The mold film (M), (M) is peeled off, and (2) / (1) /
A laminated sheet having the layer configuration of (2) was obtained. The retardation value of this laminated sheet is 8 nm, and the surface hardness (JIS K540
(0, 100 g load) was 3H, and the visible light transmittance at 550 nm was 89%.

An SiO ₂ layer having a thickness of 90 Å as an example of the inorganic thin layer (3) is formed on both sides of one side of the active energy ray-curable resin cured material layer (2) of the laminated film by sputtering. And further sputtered with ITO on one of the surfaces to a thickness of 45
A transparent conductive layer (4) of 0 Å was formed. The adhesion of the transparent conductive layer (4) was good.

In the above, when the monomer (b) is not blended with the active energy ray-curable resin (a) as a resin liquid for forming the active energy ray-curable resin cured material layer (2), the optically isotropic base film ( In terms of the adhesion at the interface between the active energy ray-curable resin cured product layer (2) and the active energy ray-curable resin cured product layer (2) and the inorganic thin layer (3), , The quality tended to vary.

On the other hand, when a composition in which the active energy ray-curable resin (a) is mixed with the monomer (b) is used as the resin liquid for forming the active energy ray-curable resin cured product layer (2), Adhesion at the interface between the optically isotropic substrate film (1) and the active energy ray-curable resin cured layer (2), the active energy ray-curable resin cured layer (2) and the inorganic thin layer (3)
Adhesion at the interface with the substrate was remarkably excellent.

The (3) / (2) / (1) / (2) / (3) /
Using two transparent conductive sheets having the layer configuration of (4),
According to a conventional method, a dot spacer is formed on the transparent conductive layer (4) surface of one of the two sheets in advance.
An inner touch panel was manufactured with the transparent conductive layer (4) side of the two sheets facing each other.

In this inner touch panel, delamination did not occur when keying and pen input operations were repeated, and the inner touch panel had a long life and sufficiently satisfied the strict standards of users.

The obtained inner touch panel is placed under the upper polarizing plate (or upper polarizing plate / phase plate / liquid crystal cell / lower surface) of the liquid crystal display element having the structure of upper polarizing plate / liquid crystal cell / lower polarizing plate. The liquid crystal display element is fabricated by incorporating the liquid crystal display element into a liquid crystal display element having a configuration of a side polarizing plate).
When its performance was evaluated, the visibility was 3 times higher than that of a conventional touch panel where a transparent touch panel was placed on the top polarizing plate.
It has been found that the light transmission amount is significantly improved by 0 to 40%. Further, since the cured resin layer (2) was provided, the stiffness (rigidity), hardness, heat resistance, solvent resistance, scratch resistance, and moisture permeability were good.

The two transparent conductive sheets (3) / (2) / (1) / (2) / (3) / (4) obtained above have the transparent conductive layer (3) side. When the cells were made to face each other and a ferroelectric polymer liquid crystal layer was interposed between the two sheets to produce a ferroelectric polymer liquid crystal display device, the life was very favorable. .

[0066]

The photoisotropic substrate film (1) obtained by the method of the present invention / the cured layer of the active energy ray-curable resin
In the case of a transparent conductive sheet containing the layer structure of (2) / inorganic thin layer (3) / transparent conductive layer (4) (the inorganic thin layer (3) may be omitted), an optically isotropic substrate The adhesion at the interface between the film (1) and the active energy ray-curable resin cured product layer (2) and the adhesion at the interface between the active energy ray-curable resin cured product layer (2) and the inorganic thin layer (3) are improved. It is excellent, has no variation in quality, and does not require any special process. Therefore, the present invention is useful as an industrial production method of a transparent conductive sheet.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a transparent conductive sheet obtained by a method of the present invention.

[Explanation of symbols]

 (1) ... optically isotropic substrate film, (2) ... cured resin layer, (3) ... inorganic thin layer, (4) ... transparent conductive layer

Claims (3)

[Claims] An active energy ray-curable resin cured product of a polymer film having a layer structure in which an active energy ray-curable resin layer (2) layer is provided on at least one surface of an optically isotropic substrate film (1). Direct or inorganic thin layer on layer (2)
In obtaining a transparent conductive sheet provided with the transparent conductive layer (4) via (3), the active energy ray-curable resin is used as a resin liquid for forming the active energy ray-curable resin cured layer (2). A composition comprising (a) a monomer (b) having a radical-reactive double bond and at least one group selected from the group consisting of an epoxy group, a hydroxyl group, an isocyanate group and an alkoxysilane group. A method for producing a transparent conductive sheet, comprising: 2. The method according to claim 1, wherein the optically isotropic substrate film (1) is a film of polycarbonate, polyarylate, polyether sulfone, polysulfone or amorphous polyolefin. 3. The method according to claim 1, wherein the proportion of the monomer (b) is 0.01 to 15 parts by weight per 100 parts by weight of the active energy ray-curable resin (a).