JP2003305791A - Transparent conductive film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent film for a display which is excellent in optical isotropy, heat resistance, and scratch resistance and in which a dimensional change after being heated at a high temperature is reduced, color nonuniformity is controlled, and the reflection of external light is enough prevented. <P>SOLUTION: In the transparent conductive film, coating films are formed on both surfaces (surface A and surface B) of a polymer film F, and a transparent conductive layer in which the average center line roughness [Ra(A)] of the outside surface of the coating film (A1) on the surface A side is 30 nm-1 μm, and the average center line roughness [Ra(B)] of the outside surface on the surface B side is 30 nm or below is formed. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a transparent conductive film suitable as various display bodies. For more details,
Liquid crystal display device, electroluminescence (EL) display device, electrophoresis type, thermal rewritable type, PDLC
And a chiral nematic liquid crystal, an electrochromic system, a twist ball type, a toner display system, and the like.

[0002]

2. Description of the Related Art In recent years, liquid crystal display elements, organic EL display elements, digital paper, and various other types of displays have been demanded to have improved damage resistance, reduced weight, and reduced thickness. Alternatively, a semiconductor film such as an oxide of a tin-indium alloy, a metal film such as an oxide film of gold, silver, or a palladium alloy, or a film formed by combining the semiconductor film and the metal film is provided as a transparent conductive layer. Investigations using a transparent conductive film as an electrode substrate of a display body are ongoing. However, when a plastic film is used instead of the glass substrate, it is necessary to supplement optical isotropy, heat resistance, dimensional stability, chemical resistance, gas barrier property, etc. due to distortion during molding.

Therefore, for example, in liquid crystal display device applications, JP-A-59-158015 and JP-A-7-24666.
As described in Japanese Patent Publication No. 1, a plastic film having excellent optical isotropy, heat resistance and dimensional stability is used as a support, and a coating film having excellent chemical resistance, a coating film having low gas permeability, And what laminated | stacked the transparent conductive layer is used.

However, a display body made of such a conventional plastic film (also referred to as a polymer film) has color unevenness due to unevenness in the thickness of the coating layer, and a reduction in contrast due to reflection of external light. At present, a sufficient display quality has not been obtained because an image is reflected.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances, has excellent optical isotropy and heat resistance, has very little dimensional change after high temperature heating, and has little color unevenness. The main object of the invention is to provide a high-quality transparent conductive film in which reflection of external light is sufficiently prevented and which is also excellent in scratch resistance.

[0006]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that a polymer having a specific molecular structure as a polymer film as a support can be formed by a highly accurate film forming technique. Using a plastic film obtained by controlling the three-dimensional refractive index, which has extremely low heat resistance, optical isotropy, and dimensional change after heating at high temperature, one of the outermost layers of the film has a smaller refractive index than the film. A film having a coating film having a surface roughness Ra of more than 30 nm and excellent in scratch resistance, and a coating film having excellent chemical resistance on the other surface and having a refractive index substantially equal to that of the film is excellent in display quality. I found that. In addition, since the difference in the refractive index between the coating film and the polymer film that is the support and the unevenness of the film thickness of the coating layer cause the display quality, especially the color unevenness, the contrast reduction and the image reflection due to the reflection of external light may occur. I found it. The present invention has been made based on these findings.

That is, the present invention is as follows. 1. At least one coating film (A1) and (B1) is formed on both surfaces (A surface and B surface) of the polymer film (F), and the transparent conductive layer (E) is formed on the outermost surface of the B surface.
Of the transparent conductive film having a center line average roughness (Ra (A)) of 30 nm to 1 μm.
And the outermost surface on the B side is the center line average roughness (Ra
(B) is 30 nm or less, and the coating film (A
A transparent conductive film satisfying the following formulas (1) and (2), where nA1 is the refractive index of 1), nF is the polymer film, and nB1 is the refractive index of the coating film (B1). nA1 <nF and nA1 <nB1 (1) nF-0.02 <nB1 <nF + 0.02 (2)

2. The minimum value of the 5 ° regular reflectance (a) of the A surface for light with a wavelength of 400 nm to 780 nm is 7% or less, and is smaller than the minimum value of the 5 ° regular reflectance of the B surface for light with a wavelength of 400 nm to 780 nm (b). Small and (a)
From the wavelength of the light that gives
The standard deviation σ (a) of 5 ° regular reflectance of the surface is smaller than 0.5%.

3. The transparent conductive film according to 1 or 2 above, wherein the polymer film (F) is made of polycarbonate, polyester, or a mixture thereof.

4. The transparent conductive film according to any one of 1 to 3 above, wherein the polymer film comprises a polymer containing a repeating unit having a fluorene skeleton, or a polymer containing the repeating unit as a copolymerization component.

5. The polymer film has the following formula (5)

[0012]

[Chemical 3]

[In the above formula (5), R _{1 to} R ₈ are each independently a hydrogen atom, a halogen atom and a carbon number of 1 to 6]
Is at least one group selected from the following hydrocarbon groups. ] The repeating unit represented by the following formula (6)

[0014]

[Chemical 4]

[In the above formula (6), R _{9 to} R ₁₆ are each independently a hydrogen atom, a halogen atom and a carbon number of 1 to 1.
6 is at least one group selected from the hydrocarbon groups having 6 and X is a hydrocarbon group having 1 to 15 carbon atoms. ] The transparent conductive film of the above-mentioned 1 to 4 which consists mainly of a copolycarbonate containing a repeating unit represented by the above, and whose repeating unit represented by the above formula (5) is 10 to 90 mol% of the whole.

6. The coating film (A1) contains siloxane-based resin and silicone resin fine particles as main components, wherein the transparent conductive film according to any one of 1 to 5 above.

7. The coating film (B1) contains a crosslinked resin having a fluorene skeleton as a main component, and the transparent conductive film according to any one of 1 to 6 above.

8. A coating film (A1) on one surface (A surface) of the polymer film (F) is laminated in the order of a fine particle containing layer (P), a high refractive index layer (H) and a low refractive index layer (L). (P) and (H), and (H) and (L) are in contact, and the refractive indices of (H) and (L) are nH,
When nL and the film thickness are dH and dL, the following equations (7)-
The above items 1 to 7 characterized in that (10) is simultaneously satisfied.
Transparent conductive film. nL <1.5 (7) nH ≧ 1.5 (8) 90 (nm) <nLdL <180 (nm) (9) 90 (nm) <nHdH <360 (nm) ... (10)

9. The high refractive index layer (H) is made of Ti, Zr,
And a transparent coating layer having at least one oxide selected from In as a main component, wherein the low refractive index layer (L) is a coating layer having silicon and oxygen as main components. Conductive film.

10. Si, Al, Ti, Mg, Ta,
Oxides and fluorides of at least one metal or a mixture of two or more metals selected from Ce, In and Zr,
The transparent conductive film according to any one of 1 to 9 above, wherein at least one gas barrier layer containing an inorganic material such as a nitride or an oxynitride as a main component is formed.

11. The transparent conductive film according to 1 to 10 above, wherein the gas barrier layer is present between the coating film (A1) and the polymer film (F) and / or between the coating film (B) and the transparent conductive layer (E).

12. The transparent conductive film as described above, wherein a color filter layer is formed between the transparent conductive layer (E) and the coating film (B).

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION The polymer film (F) used in the present invention has not only excellent transparency and heat resistance but also low water absorption, water vapor barrier property and excellent optical isotropy.
Those having extremely little dimensional change after high temperature heating are preferably used.

The heat resistance is 170 ° C. or higher, preferably 19
It has a glass transition temperature of 0 ° C or higher, good optical properties,
Those capable of solution film formation are more preferable. Low water absorption is important for ensuring the durability of the display under high temperature and high humidity environment. Here, low water absorption means a water absorption rate of 0.4% after 24 hours in water measured by a method according to ASTM D570.
The following is preferably 0.2% or less.

Further, it is important that the above-mentioned polymer film has excellent water vapor barrier properties, and the water vapor permeability coefficient at 40 ° C. and 90% RH is 50 g · 100 μm / m ² / d.
ay or less, preferably 35 g · 100 μm / m ² / da
Choose something that is less than or equal to y. By having such a high water vapor barrier property, liquid crystal panels and organic E
When used as a substrate for an L panel or the like, deterioration of the element due to the influence of water can be suppressed.

Regarding optical isotropy, depending on the use, the following formulas (i) and (ii) | R (550) | ≤20 (nm) (i) K = | [nz- (nx + ny) / 2] × d | ≦ 100 (nm) (ii) is preferably satisfied. In the above formula (i), R
(550) is an in-plane retardation value of the polymer film with respect to light having a wavelength of 550 nm, and in the formula (B), nx, ny, and nz are x-axis and y-axis with the thickness direction of the polymer film as the z-axis. , Is the three-dimensional refractive index for light with a wavelength of 550 nm in the z-axis direction, and d is the thickness of the polymer film.

The retardation value of the polymer film is the product of the film thickness d and the difference Δn in the refractive index between the orientation direction of the film and the direction perpendicular thereto when light passes through the film having the thickness d. It is represented by Δn · d (nm). In addition,
This phase difference can be expressed by an angle, and the conversion formula of the phase difference R1 expressed by the angle and the phase difference R2 in nm is R1.
(Degree) = (R2 (nm) / λ) × 360 (λ
Is the measurement wavelength of the phase difference).

The transparent polymer film of the present invention has very high heat resistance, has very little dimensional change after high temperature heating, and has a dimensional change rate of 0. 2 after heat treatment at 150 ° C. for 2 hours. It is less than 05% and provides a display body having excellent display quality. As for the dimensional change rate, the dimensional change rate after heat treatment at 180 ° C. for 2 hours in the flow direction is more preferably 0.1% or less.

A thermoplastic polymer is suitable as a material for providing the polymer film. The thermoplastic polymer is not particularly limited, but is preferably polycarbonate, polyester or polyester carbonate, which has a good balance of heat resistance, film-forming property by solution casting method, transparency, handleability, gas barrier property, mechanical properties and the like. It is mentioned as a thing.

These polymers have the following formula (X)

[0031]

[Chemical 5]

Those containing a structural unit having a fluorene skeleton represented by the following as a main component or a copolymerization component are particularly excellent in the above properties and particularly excellent in gas barrier properties. Two or more kinds of these structural units may be contained. In the above formula, R ^{1 to} R ⁸ are each independently selected from at least a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms such as a methyl group and an ethyl group, and a hydrocarbon group such as an aryl group such as a phenyl group. It is a kind of group.

Specific examples of the monomer used for introducing the structural unit represented by the above formula X into the polymer include, for example, fluorene 9,9-di (4-phenol) and fluorene 9 , 9-di (3-methyl-4-phenol). These are preferably 10 to 90 mol% and more preferably 30 to 80 mol% of the whole polymer as a copolymerization component. If it is less than 10 mol%, the sufficiently excellent isotropicity and heat resistance described later cannot be obtained, and the dimensional change before and after high temperature heating becomes large.
If it is more than mol%, the light transmittance is lowered and the film becomes brittle, which is not preferable.

Further, as a polymer material constituting the transparent polymer film of the present invention, the following formula (5) is used.

[0035]

[Chemical 6]

A repeating unit represented by the following formula (6)

[0037]

[Chemical 7]

A polycarbonate having a repeating unit represented by the formula (1) as a copolymerization component, and the repeating unit represented by the formula (1) is 10 to 90 mol% of the entire repeating unit is more preferable.

In the above formula (5), R _{1 to} R ₈ are each independently at least one selected from a hydrogen atom, a halogen atom and a hydrocarbon group having 1 to 6 carbon atoms. Examples of the hydrocarbon group having 1 to 6 carbon atoms include monovalent alkyl groups such as methyl group and ethyl group, and aryl groups such as phenyl group.

In the above formula (6), R _{9 to} R ₁₆ are each independently a hydrogen atom, a halogen atom and a carbon number of 1 to 6.
X is a hydrocarbon group such as an alkylene group having 1 to 15 carbon atoms. Specific examples of X include, for example, methylene, 1,1-ethylene, 2,2-propylene, 2,2-butylene, 2,2- (4-methyl) pentylene, 1,1-cyclohexylene, 1, 1- (3,3,
5-trimethyl) cyclohexylene, norbornane-
2,2-diyl, tricyclo [5.2.1.02,6]
Decane-8,8'-diyl, phenylmethylene, diphenylmethylene, 1,1- (1-phenyl) ethylene,
2,2-hexafluoropropylene, 2,2- (1,
1,3,3-tetrafluoro-1,3-dichloro) propylene and the like can be mentioned.

Particularly preferred polycarbonates include
Fluorene 9,9-di (3-methyl-4-phenol)
The repeating unit represented by the above formula (5) derived from (in the above formula (5), R _{1 to} R ₈ are hydrogen atoms (provided that one of R ₂ and R ₃ is a methyl group, and R ₅ and Corresponding to the case where one of R ₈ is a methyl group) and a repeating unit represented by the above formula (6) in which X is 2,2-propylene and R _{9 to} R ₁₆ are all hydrogen atoms. Polycarbonate as a copolymerization component. Here, the repeating unit represented by the above formula (5) is preferably 10 to 90 mol%, more preferably 30 to 80 mol%, further 4
0-60 mol% is more preferable. By setting the repeating unit represented by the formula (6) to 10 mol% or more, the glass transition temperature becomes 170 ° C. or more, and excellent heat resistance can be obtained.
Low water absorption and water vapor permeability. In addition, the surface hardness that can be evaluated by pencil hardness and the like is remarkably improved, and the dimensional change after heating at a high temperature is extremely reduced, so that the substrate exhibits favorable characteristics as a display substrate. Furthermore, as the content of the repeating unit represented by the above formula (5) increases, the optical isotropy of the polymer film increases, and when a polycarbonate of more than 30 mol% is used, the above retardation value is used. An R (550) of 10 nm or less is obtained. Furthermore, when a film is formed using a polycarbonate containing 50 mol% or more of the repeating unit represented by the above formula (5), the film is formed by the solution casting method described below, and the above formulas (i) and (ii) Can be simultaneously satisfied, and a polymer film having an extremely small rate of dimensional change of the film after heat treatment at 180 ° C. for 2 hours can be obtained.

In addition to the above-mentioned polycarbonate, examples of the polymer material constituting the polymer film used in the present invention include polyester and polyester carbonate. As the acid component in the polyester or polyester carbonate, carbonic acid, aliphatic dicarboxylic acid,
Aromatic dicarboxylic acids can be used. As the aromatic dicarboxylic acid, terephthalic acid and isophthalic acid are preferable.

The polycarbonate, polyester and polyester carbonate may be used as a mixture of two or more kinds.

The number average molecular weight of these polycarbonates, polyesters and polyester carbonates is preferably 30,000 to 300,000. A polymer having a larger molecular weight has improved mechanical properties and heat resistance, but if it is too large, molding becomes difficult.

Generally, the film forming method includes a melt extrusion film forming method and a solution casting film forming method, and it has excellent optical isotropy satisfying the above formulas (i) and (ii). The preferred casting method for obtaining the polymer film is a solution casting method. Although the solution casting method is inferior in productivity to the melt extrusion method, it has few defects such as die line, gelation product and fish eye, and has much better surface smoothness than the melt extrusion method. Further, in the solution casting method, even in the case of a high molecular weight resin whose melt viscosity is too high or easy to be colored or cannot be molded by melt extrusion in the case of being soluble in the solvent used, it is possible to mold, A film having excellent heat resistance can be obtained. Further, in the solution casting method, the three-dimensional refractive index of the film can be controlled by adjusting the characteristics of the die, the condition of the casting belt, the drying conditions, the film tension and the transport conditions, and the like. In order to satisfy the above formulas (A) and (B), it is particularly important to adjust the amount of solvent contained in the film in the molding step, the drying temperature, and the tension applied to the film. The apparent amount and Tg of the film are determined by the amount of the solvent contained in the film, but the drying temperature is preferably set to the apparent Tg or lower. The tension applied to the film tends to increase in the film transport direction when the film is formed by, for example, a roll winding method, but a device that can apply the tension in the direction perpendicular to the film transport direction is used. It is also effective to perform molding under the condition that the difference between the two tensions does not occur as much as possible and the tension is suppressed as much as possible.

In the solution casting method, the solvent used for film formation may remain in the polymer film. Residual solvent plasticizes the film, resulting in a decrease in glass transition temperature and a decrease in mechanical properties. Therefore, in the polymer film of the present invention, it is preferable to completely remove the residual solvent, preferably 1% by weight or less, more preferably 0.5% by weight or less. When a plasticizer, a surfactant or the like is added to the film, the residual amount of these is not included in the residual amount of solvent.

The thickness of the above-mentioned polymer film depends on the display quality when processed into various display bodies, the ease of handling in the step of molding the substrate, the ease of handling in the step of assembling the display body, and the solution flow. 2 from the viewpoint of film forming efficiency during film forming
The thickness is 0 to 500 μm, preferably 50 to 400 μm, and more preferably 70 to 300 μm.

When a transparent conductive layer is provided as the outermost layer on the B side of the polymer film to be used as an electrode for a liquid crystal display, the unevenness in the gap of the liquid crystal cell deteriorates the display quality. The thickness unevenness is preferably ± 5% or less, more preferably ± 2.5% or less.

In the present invention, the coating films (A1) and (B) are formed on both sides A and B of the polymer film (F).
1), and a transparent conductive film having a transparent conductive layer (E) as the outermost layer on the B side is provided. Here, the center line average roughness (Ra (A)) of the outermost layer (outermost surface) of one surface (A surface) is 30 nm to 1 μm, and the refractive index of the coating film (A1) is nA1,
When the refractive index of the polymer film is nF and the refractive index of the coating film (B1) is nB1, F, A1, and B
1 satisfies the following equations (1) nA1 <nF and nA1 <nB1 (1), so that, for example, when the 5 ° specular reflectance is evaluated, the contrast is reduced due to the reflection of external light and the image is reflected. Can be made smaller. The center line average roughness (Ra (A)) is preferably 30 nm to
It is 0.3 μm. If it is smaller than 30 nm, it is difficult to sufficiently suppress the reflection of an image, and if it is larger than 0.3 μm, the resolution of the display is lowered, which is not preferable.

Here, the coating film (A1) has sufficient durability against solvents and chemicals when the display panel is assembled, and includes various crosslinked resins, for example, crosslinked structures of polysiloxane-based resin, and acrylic. Crosslinked structure of epoxy resin, epoxy resin, melamine resin, urethane resin,
It is mainly composed of a crosslinked structure such as an alkyd resin, and contains fine particles in the coating layer. As the fine particles, for example, resin fine particles containing silicone, acryl, styrene, melamine or the like as a main component are preferably used. The average particle size of the fine particles is preferably 1 to 10 μm, and more preferably 1 to 5 μm. If the particle size is small, it is difficult to form a surface having a roughness sufficient to suppress the reflection of an image, and if the particle size is too large, the particle shape becomes conspicuous and the appearance becomes poor. The content of the fine particles is the same as the above-mentioned crosslinked structure 1
It is preferable to add 1 to 50 parts by weight to 00 parts by weight. When the content is low, it becomes difficult to form a surface having sufficient roughness, and when the content is too high, the coating film tends to be discontinuous.

A particularly preferred coating film (A1) is
The main component is a crosslinked structure of polysiloxane resin and fine particles of silicone resin, and the refractive index of each component is 1.
It is 55 or less, more preferably 1.45 or less. The film thickness of the coating film (A1) is smaller than the average particle size of the contained fine particles and is in the range of 1 to 10 μm.

Next, the center line average roughness Ra (B) of the outermost surface of the polymer film (F) opposite to the surface on which the coating film (A1) is formed has a center line average roughness Ra (B) of 30 nm or less. Thus, a coating film (B1) having a refractive index almost equal to that of the polymer film (F) is formed. As a result, it is possible to suppress color unevenness due to the difference in refractive index between the various coating films and the polymer film as the support and the unevenness in the thickness of the coating layer (B1). The center line average roughness Ra (B) is preferably 20 nm or less. In particular, when the transparent conductive film of the present invention is used for liquid crystal display applications, Ra
When (B) is 20 nm or less, the uniformity of the cell gap is maintained, and a display having excellent display characteristics can be obtained. Here, “substantially equal” means that the refractive index of the polymer film (F) is nF and the refractive index of the coating layer (B1) is n.
When B1 is set, B1 satisfying the condition of the following formula (2) is preferable in terms of suppressing color unevenness.

NF-0.02 <nB1 <nF + 0.02 (2) Here, the coating layer (B1) is a cross-link having sufficient durability against solvents and chemicals when the display panel is assembled. Resin, for example, polysiloxane resin crosslinked structure, acrylic resin crosslinked structure, epoxy resin,
It is preferably composed of a crosslinked structure such as a melamine resin, a urethane resin and an alkyd resin. These crosslinked structures are made of a resin that is cured by irradiation with radiation such as ultraviolet rays and electron beams. Specifically, the crosslinked structure does not contain acryloyl group, methacryloyl group, vinyl group, etc. A resin containing a saturated double bond is preferable, and an acrylic resin containing an acryloyl group is particularly preferable from the viewpoint of reactivity. These resins may be used alone or as a mixture of several kinds, but from the viewpoint of solvent resistance, it is preferable to use an acrylic resin having two or more acryloyl groups in the molecule or unit structure. . Examples of such polyfunctional acrylate resins include, but are not limited to, urethane acrylate, polyester acrylate, epoxy acrylate, silicone acrylate, and the like. As the resin forming the particularly preferable coating film (B1), an acrylate resin having a fluorene skeleton represented by the formula (X) is preferable. The acrylate-based resin having the fluorene skeleton is characterized in that it has good heat resistance, a high refractive index, and a surface roughness that makes it easy to form a coating film with good scratch resistance, and is suitable for the transparent conductive film of the present invention. Is. In this case, it is particularly preferable to use in combination with a polycarbonate film composed of the repeating units represented by the above formulas (5) and (6).

The coating film (B1) may contain substantially no fine particles, but may contain inorganic fine particles for the purpose of satisfying the condition of the above formula (2). Here, the inorganic fine particles are Si, Al, Ti, Mg, Ta,
The particle size of the oxide, fluoride, nitride or oxynitride of at least one metal or a mixture of two or more metals selected from Ce, In and Zr is 100 n.
Inorganic fine particles of m or less are preferable. If the particle size of the inorganic fine particles is too large, light scattering by the inorganic fine particles causes cross-linking structure 10.
It is preferable to add 70 parts by weight or less with respect to 0 parts by weight. When the amount of the fine particles added is too large, the film becomes brittle in strength and the coating film tends to be discontinuous. Further, the surface roughness becomes remarkable, which is not preferable.

The thickness of the coating film (B1) is preferably in the range of 1 to 10 μm, more preferably 1 to 5 μm.
Is the range.

As the method for forming the coating films (A1) and (B1), known coating methods and curing methods can be used.

As described above, the coating film (A1) is formed on one surface of the polymer film (F) and the coating film (B1) is formed on the other surface of the polymer film (F).
The minimum value (a) of the 5 ° regular reflectance for light having a wavelength of 400 nm to 780 nm is 7% or less and the wavelength of (B) is 4
It is smaller than the minimum value (b) of 5 ° regular reflectance for light of 00 nm to 780 nm, and further, the standard deviation σ of 5 ° regular reflectance for light in the range of −40 nm from the wavelength of the light corresponding to (a). (A) becomes smaller than 0.5%,
A transparent conductive film having little color unevenness, sufficient prevention of reflection of external light, and excellent scratch resistance.

The scratch resistance in the present invention can be evaluated by measuring the hardness and the plastic deformation rate with a commercially available micro hardness meter. For example, ENT manufactured by Elionix Co., Ltd.
-1100, the measurement condition is the maximum load 0.49m
N, data loading step 1.96 μN, data loading interval 40 msec, load holding time when maximum load is reached 1
sec, the indenter used is a triangular pyramid (115 °) whose tip material is diamond, and the hardness and plastic deformation of the transparent polymer film for a display of the present invention, which is an average value when 5 measurements are continuously performed for each load. When the rate is measured, the hardness given by the following formula [I] is 18 or more, and the plastic deformation rate is 50% or less as given by the following formula [II]. Hardness = 3.7926 × 10 ^-2 × maximum load / (maximum displacement amount) ² [I] (hardness: kg / mm ² , maximum load: mg, maximum displacement amount: μm) Plastic deformation rate = after unloading Displacement / Maximum displacement x 100 [II] (Plastic deformation rate:%, Displacement after unloading: μm, Maximum displacement: μm)

Further, as a preferred embodiment of the present invention, the transparent film for display of the present invention has a fine particle-containing layer (P), a high refractive index layer (H) and a low refractive index layer on the A side of the polymer film (F). It includes one in which the coating films are laminated in the order of the refractive index layer (L). In this case, the outermost surface of A1 becomes the low refractive index layer (L). With such a configuration, it is possible to obtain a transparent conductive film in which the outermost surface (L) of surface A has a further lower 5 ° regular reflectance and the reflection of external light is sufficiently prevented. Here, when the refractive indexes of the high refractive index layer (H) and the low refractive index layer (L) are nH and nL and the film thicknesses are dH and dL, the following expressions (7) to (10) are simultaneously satisfied. To form (H) and (L). nL <1.5 (7) nH ≧ 1.5 (8) 90 (nm) <nLdL <180 (nm) (9) 90 (nm) <nHdH <360 (nm) ... (10)

As the fine particle-containing layer (P), the same ones as described in the above coating layer (A1) are suitable, but in this case, the coating (P) has a refractive index of 1.5 or more and lower than nH. It is preferable to form a layer because the reflection of external light can be further reduced. The high refractive index layer (H) is preferably a coating layer containing at least one oxide selected from Ti, Ce, Zr, In, Al and Si as a main component, and particularly an oxide of Ti, Zr or In. More preferable. You may use these 2 or more types together.
As the low refractive index layer (L), a coating layer containing silicon and oxygen as main components is preferable, and a coating layer containing siloxane resin containing fluorine or magnesium fluoride as main components is preferable.

As the transparent conductive layer in the present invention, known metal films, metal oxide films and the like can be applied, but among them, the metal oxide film is preferable from the viewpoint of transparency, conductivity and mechanical properties. For example, metal oxide films such as indium oxide added with tin, tellurium, cadmium, molybdenum, tungsten, fluorine, zinc and germanium as impurities, cadmium oxide and tin oxide, zinc oxide added with aluminum as impurities, titanium oxide, etc. Can be mentioned. Among them, indium oxide as a main component and one or more kinds of oxides selected from the group consisting of tin oxide and zinc oxide are included, and 2 to 20% by weight of tin oxide and / or zinc oxide is contained. The transparent conductive layer containing 2 to 20% by weight is transparent,
It has excellent conductivity and is preferably used. When the film of the present invention is used in an organic EL, it is selected from the group consisting of tin oxide and zinc oxide containing indium oxide as a main component for the purpose of controlling the work function of the transparent conductive layer and improving the luminous efficiency. A film containing one or more oxides, tin,
Elements other than zinc may be added.

As a method for forming the transparent conductive layer, a sputtering method is mainly used, and a direct current sputtering method, a high frequency magnetron sputtering method, an ion beam sputtering method and the like can be applied. From the viewpoint of productivity, the magnetron sputtering method is preferable. . The thickness of the transparent conductive layer is
The thickness is preferably 10 to 1000 nm in order to obtain sufficient conductivity. The transparent polymer film for a display of the present invention preferably has a total light transmittance in the visible light region of 80% or more, more preferably 85% or more. 8
If it is less than 0%, problems such as deterioration of visibility may occur.

The transparent conductive layer is the above-mentioned coating layer (B
It is formed on the surface on which (1) is formed and is provided in contact with (B1).

The transparent conductive film of the present invention has a small water vapor transmission coefficient and a high water vapor barrier property, but it may have a gas barrier layer, or a transparent conductive layer or the like, if necessary. The gas barrier layer and the transparent conductive layer are both formed of the polymer film and the coating films (A1), (B
1) and may be on the outer layer (that is, the outermost surface) of (A1) and (B1).

Examples of such gas barrier layers include polyvinyl alcohol, polyvinyl alcohol polymers such as ethylene-vinyl alcohol copolymers, polyacrylonitrile, polyacrylonitrile copolymers such as styrene-acrylonitrile copolymers, or polyvinylidene. Known polymer coating materials such as chloride and Si, A
1, at least 1 selected from Ti, Mg, Zr, etc.
Inorganic materials such as oxides, fluorides, nitrides or oxynitrides of one kind of metal or a mixture of two or more kinds of metals can be mentioned. Among them, an inorganic material containing Si oxide, nitride, or oxynitride as a main component is preferable because of excellent transparency and gas barrier property. In addition, a silicon oxide containing silicon and oxygen as main components, or a thin film containing silicon and oxygen as main components and containing at least fluorine and magnesium and chemically bonding silicon and fluorine has a gas barrier property, transparency, It is preferable in terms of surface smoothness and low film stress. Here, the ratio of oxygen atoms to silicon atoms is preferably 1.5 or more and less than 2. Due to this ratio, the transparency and gas barrier property of the thin film change in a trade-off relationship, and if it is less than 1.5, the transparency required for display applications may not be obtained. Further, the fluorine atom is chemically bonded to silicon and magnesium, and the ratio of the bond (A) between the fluorine atom and the silicon atom and the bond (B) between the fluorine atom and the magnesium is preferably (A)> (B). In addition, the ratio of magnesium contained in the gas barrier layer is 2.5 to 20 a in terms of element ratio with respect to coexisting silicon.
The range of tom% is preferable. It is presumed that such a ratio can reduce not only good gas barrier properties and transparency but also particularly film stress. Therefore, even if the film thickness of the gas barrier layer is increased, the transparent polymer film for display body is increased. The deformation of can be reduced. The chemical bonding state of elemental fluorine existing in the gas barrier film is analyzed and determined by, for example, X-ray photoelectron spectroscopy. In X-ray photoelectron spectroscopy, Kα ray of Al was used as an X-ray source, and 284.6e of neutral carbon C1s was used.
When the horizontal axis is corrected with V, the chemical bond state of fluorine is 68
The presence of the F1s peak (A) derived from the bond between fluorine and silicon observed near 7 eV and the F1s peak (B) derived from the bond between fluorine and magnesium observed at a low bond energy side of about 1.5 eV from this, and , Determined by their intensity ratio.

Examples of the method of forming the gas barrier layer include a vapor phase deposition method such as a sputtering method, a vacuum vapor deposition method, an ion plating method and a plasma CVD method for forming a film by depositing a material in the vapor phase. These gas barrier layers are used singly or in combination of two or more, and are set to a thickness capable of expressing the target performance. Particularly, when the inorganic thin film material is used as the gas barrier layer, the film thickness is 2 nm to
The range of 1 μm is preferable. Gas barrier layer thickness is 2 nm
If it is less than the above, it is difficult to form a film uniformly, and a gas permeability is increased because a part where the film is not formed is generated. On the other hand, when the thickness is more than 1 μm, not only the transparency is deteriorated, but also when the substrate is bent, cracks are generated in the gas barrier layer to increase the gas permeability.

These gas barrier layers are used singly or in combination of two or more kinds so as to have a thickness capable of exhibiting target performance.

The gas barrier layer is provided between the coating film (A1) and the polymer film (F), between the coating film (B1) and the polymer film (F), or on the coating layer (B1). It is formed.

Furthermore, in the transparent conductive film of the present invention,
For example, a color filter layer may be provided for the purpose of imparting a color display function to a liquid crystal display element produced using this. The color filter can be formed by a known technique such as a dyeing method, a pigment dispersion method, an electrodeposition method or a printing method. The color filter layer is preferably formed between the transparent conductive layer (E) and the coating film (B) of the transparent conductive film.

Since the transparent conductive film of the present invention has good scratch resistance as described above, it is connected to the printed wiring board using, for example, HSC (heat seal connector) or ACF (anisotropic conductive film). At that time, extremely good connection reliability can be secured. In addition, particularly when the transparent conductive film of the present invention is applied to a liquid crystal display body, the amount of the substrate deformed by the spacer arranged inside the liquid crystal panel becomes small, and a liquid crystal panel having uniform display characteristics with few spots is obtained. It becomes possible to obtain.

[0071]

According to the present invention, a polymer film having a specific molecular structure is used as a support, and one surface of the film has a smaller refractive index than the film and a surface roughness Ra.
Of 30 nm to 1 μm and having excellent scratch resistance, a coating film having excellent chemical resistance with a refractive index almost equal to that of the film is formed on the other surface, and a specific surface roughness is formed on the coating film. It has excellent optical isotropy and heat resistance by forming a transparent conductive layer, and has very little dimensional change after high temperature heating and excellent scratch resistance. It is possible to provide a transparent conductive film for a display body in which entrapment is sufficiently prevented.

The transparent conductive film is, for example, a liquid crystal display device, an electroluminescence (EL) display device, an electrophoretic type, a thermal rewritable type, a PDLC system, a chiral nematic liquid crystal, an electrochromic system, a twist ball type, a toner display system. It is suitable as a transparent electrode substrate for a display using the above.

[0073]

EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the examples, parts and% are based on weight unless otherwise specified. Further, various measurements in the examples were performed as follows. (1) Roughness Ra: Surface roughness meter D manufactured by Nippon Vacuum Technology Co., Ltd.
The measurement was performed using EKTAK3. (2) 5 ° regular reflectance: U-4000 manufactured by Hitachi, Ltd.
The measurement was performed using a spectrophotometer. (3) Refractive index: Measurement was performed using a refractometer 2-T manufactured by Atago Co., Ltd. The temperature at the time of measurement was 25 ° C., and the light source was D line 589 nm of a sodium lamp. The coat layer was obtained by coating glass and peeling it off. (4) Hardness measurement: The hardness of the thin film was measured using ENT-1100, an ultrafine hardness measuring device manufactured by Elionix Co., Ltd. Measurement conditions are maximum load 0.49mN, data acquisition step 1.96μN, data acquisition interval 40ms
ec, a load holding time of 1 sec when the maximum load is reached, the indenter used is a triangular pyramid (115 °) with a diamond tip at the tip,
It is the average of 5 consecutive measurements for each load,
The hardness is a value given by the following formula [I]. Hardness = 3.7926 × 10 ^-2 × maximum load / (maximum displacement amount) ² [I] (hardness: kg / mm ² , maximum load: mg, maximum displacement amount: μm) Plastic deformation rate measurement: plastic deformation The rate is the same as the above hardness measurement, and is a value given by the following formula [II] from the displacement after unloading obtained by the same measurement and the maximum displacement. Plastic deformation rate = displacement after unloading / maximum displacement x 100 [II] (Plastic deformation rate:%, displacement after unloading: μm, maximum displacement: μm)

The following abbreviations were used for the compound names shown below. BisA: 2,2-bis (4-hydroxyphenyl) propane BCF: 9,9-bis (4-hydroxy-3-methylphenyl) fluorene IP: 3,3,5-trimethyl-1,1-di (4- Phenol) Cyclohexylidene ITO: Indium-tin oxide ECHETMOS: 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane APTMOS: 3-Aminopropyltrimethoxysilane EVOH: Ethylene vinyl alcohol copolymer BPEFA: Bisphenoxyethanol full Orange acrylate DCPA: dimethylol tricyclodecane diacrylate (Kyoeisha Chemical Co., Ltd. "light acrylate DCP-
A ") UA: Urethane acrylate (" NK Oligo U-15HA "manufactured by Shin Nakamura Chemical Co., Ltd.)

Example 1 Bisphenol component is Bis
A polycarbonate resin having A / BCF = 50/50 (molar ratio) and an average molecular weight of 37,000 and a Tg of 211 ° C. was dissolved in methylene chloride so as to be 20% by weight. Then, this solution is applied to a thickness of 1 by a die coating method.
Cast on a 75 μm polyester film. Then, it was dried in a drying oven until the residual solvent concentration reached 13% by weight, and peeled from the polyester film. Then, while keeping the obtained polycarbonate film in a drying oven at a temperature of 180 ° C. so that the vertical and horizontal tensions do not differ as much as possible and the film is balanced with a minimum tension that can hold the film, the residual solvent concentration in the film is The transparent polymer film (F) having a thickness of 120 μm was obtained by drying until it became 0.3% by weight. The transparent polymer film thus obtained had an R (550) of 5 nm, a dimensional change rate of 0.03% after heat treatment at 180 ° C. for 2 hours, and a refractive index of 1.62.

Next, 70 parts of ethanol, 68 parts of methyltrimethoxysilane, 9 parts of water and 1.8 parts of a 1% hydrochloric acid aqueous solution were put into a flask equipped with a stirrer, a heating jacket, a condenser and a thermometer. 65 with stirring
A partial hydrolysis reaction is performed at a temperature of ℃ for about 5 hours, and after cooling, 4 parts by weight of silicone fine particles having a particle size of 3 μm and a refractive index of 1.43 and 20 parts of toluene are added to obtain a coating solution (AC1). It was This (AC1) is coated on one side of the above-mentioned polycarbonate film, and 1
A heat treatment was performed at 30 ° C. for 3 minutes to form a coating film (A1) having a thickness of 1.8 μm. The refractive index of (A1) is 1.4
3 and the center line average roughness (Ra (A)) is 100 nm.
Met.

Further, 460 parts by weight of BPEF-A, U
40 parts by weight of A, 1150 parts by weight of toluene as a diluting solvent, and Irgacure 1 manufactured by Ciba-Geigy as a photoinitiator.
15 parts by weight of 84 and 0.18 parts by weight of SH28PA manufactured by Dow Corning Toray Co., Ltd. as a leveling agent were mixed to obtain a coating solution (BC1). This (BC1) was coated on the surface of the polycarbonate film opposite to the side on which (A1) was formed, dried at 60 ° C. for 30 seconds, and then strength 1
Accumulated light amount of 700 mJ / cm ² with a high pressure mercury lamp of 60 w
Of the coating film (B
1) was formed. The refractive index of (B1) is 1.62,
The center line average roughness (Ra (B)) was 10 nm. Furthermore, an indium-tin oxide thin film layer is formed on the coating film (B1) of the film by a sputtering method.
A transparent conductive film was obtained by forming it with a thickness of 120 nm.

The evaluation results of the obtained transparent conductive film were good as shown in Table 1. That is, the refractive index of (A1) is smaller than that of the polymer films F and (B1), and R
Since a (A)> 30 nm> Ra (B), a transparent film was obtained in which contrast reduction due to reflection of external light and reflection of an image were small. Further, the refractive index of (B1) is equal to that of the polymer film F, and the standard deviation of regular reflectance σ (a) <0.3.
There was no color unevenness due to the unevenness of the coating layer thickness. Further, the surface hardness and the plastic deformation rate were 23 kg / mm ² or more and 41% or less, respectively, which were excellent.

Example 2 100 parts of EVOH was added to 72 parts of water.
It was dissolved by heating in a mixed solvent of 0 parts and 1080 parts of n-propanol to obtain a uniform solution. To this solution, 0.1 part of a leveling agent (“SH30PA” manufactured by Toray Dow Corning Co., Ltd.),
After adding 39 parts of acetic acid, 211 parts of ECHETMOS was added and stirred for 10 minutes. Further, 77 parts of APTMOS was added to this solution and stirred for 3 hours, then, the particle size was 3 μm and the refractive index was 1.4.
The coating liquid (PC1) was obtained by adding 12 parts by weight of the silicone fine particles of 3 and further stirring for 1 hour.
This (PC1) was coated on one surface of the same polycarbonate film as in Example 1 and heat-treated at 130 ° C. for 3 minutes to form a fine particle (particle diameter 3 μm) -containing layer (P) having a thickness of 1.8 μm. The refractive index of (P) was 1.52, and the center line average roughness (Ra (A)) was 120 nm.

Next, 1 part of tetrabutoxy titanate was added.
Parts, octane 12 parts, 2-butanol 12 parts, 2-
Mix 12 parts of propanol to obtain coating liquid (HC
1) was obtained. This (HC1) is coated on the surface of (P) and heat-treated at 130 ° C. for 3 minutes to give a thickness of 78 n.
m high refractive index layer (H) was formed. The refractive index of (H) was 1.78.

Further, 70 parts of ethanol, 68 parts of methyltrimethoxysilane, 9 parts of water and 1.8 parts of a 1% hydrochloric acid aqueous solution were put into a flask equipped with a stirrer, a heating jacket, a condenser and a thermometer and stirred. While 6
Partial hydrolysis reaction is carried out at a temperature of 5 ° C for about 5 hours,
After cooling, 20 parts of toluene was added to obtain a coating liquid (LC1). This (LC1) was coated on the surface of (H) and heat-treated at 130 ° C. for 3 minutes to form a low refractive index layer (L) having a thickness of 97 nm. The refractive index of (L) was 1.42.

Then, in the same manner as in Example 1, (B1) was formed on the surface opposite to the side on which these (P), (H) and (L) were formed.

The evaluation results of the thus obtained transparent film for a display were good as shown in Table 1.

[Example 3] Between the polymer film (F) and the coating film (A1) by a sputtering method,
A transparent conductive film was obtained in the same manner as in Example 1 except that a gas barrier layer having a thickness of 450 Å and containing silicon oxide as a main component was formed. The evaluation results of the obtained film were good as shown in Table 1.

Comparative Example 1 A transparent conductive film was obtained in the same manner as in Example 1 except that the coating liquid (A1) did not contain silicone fine particles having a particle size of 3 μm. As shown in Table 2, the obtained film had a center line average roughness (Ra) on the (A) surface side of 12 nm, and the reflection of the image was severe.

Comparative Example 2 In place of the coating liquid (BC1), 20 parts by weight of DCPA, 10 parts by weight of UA, 1
-Methoxy-2-propanol (30 parts by weight) and 1-hydroxycyclohexyl phenyl ketone (2) as an initiator
A transparent conductive film was obtained in the same manner as in Example 1 except that the coating film (B2) was formed by using the coating composition (BC2) obtained by mixing parts by weight. The obtained film has a refractive index of (B2) as shown in Table 2.
At 1.54, the center line average roughness was 15 nm, and the color unevenness was severe.

[0087]

[Table 1]

* (A) is the minimum value of the 5 ° specular reflectance of the surface (A) with respect to light having a wavelength of 400 nm to 780 nm, and (b) is 5 with respect to light having a wavelength of 400 nm to 780 nm (B)
The minimum value of the regular reflectance, σ (a) is the standard deviation of the regular reflectance of 5 ° with respect to the light in the range of −40 nm from the wavelength of the light that gives (a).

[0089]

[Table 2]

* (A) is the minimum value of the 5 ° regular reflectance of the surface (A) with respect to light having a wavelength of 400 nm to 780 nm, and (b) is 5 with respect to light having a wavelength of 400 nm to 780 nm (B).
The minimum value of the regular reflectance, σ (a) is the standard deviation of the regular reflectance of 5 ° with respect to the light in the range of −40 nm from the wavelength of the light that gives (a).

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G02F 1/1333 500 G02F 1/1335 505 5G307 1/1335 505 H01B 5/14 A H01B 5/14 C08L 69: 00 // C08L 69:00 G02B 1/10 A (72) Inventor Tokuaki Saito 4-3-2 Asahigaoka, Hino-shi, Tokyo Inside the Tokyo Research Center, Teijin Limited (72) Toshiaki Yatabe Asahigaoka, Hino-shi, Tokyo 4-3-2 Teijin Limited Tokyo Research Center F-term (reference) 2H090 JA09 JB02 JB03 JB12 JB13 LA01 LA02 LA05 LA06 LA17 LA20 2H091 FA02Y FA11X FA11Z FA14Y FA14Z FA44Y FC02 FC03 FC12 GA01 GA02 GA08 KA01 KA02 LA17 2K09 LA0 2 AA04 AA05 BB24 CC03 CC09 CC22 CC42 EE03 FF02 4F071 AA45 AA50 AF30 AF37 AH12 AH16 BB02 BB06 BC01 BC08 BC12 B C16 4F100 AA17E AA21E AA27E AB10A AB10B AB10C AB10D AB10E AB11A AB11B AB11C AB11D AB11E AB12A AB12B AB12C AB12D AB12E AB17A AB17B AB17C AB17D AB17E AB19E AK01A AK41A AK45A AK52D AK79D AL05D BA04 BA05 BA07 BA10C BA10D BA25 DE01D DE01E EH46 EH462 EH66 EH662 EJ86 EJ862 GB41 JG01C JJ03 JK14 JK14D JL04 JM02B JM02D JN01C JN18B JN18D JN18E YY00D 5G307 FA02 FC02 FC06 FC10

Claims (12)

[Claims] 1. At least one coating film (A) on each side (A side and B side) of the polymer film (F).
1) and (B1) are formed, and the transparent conductive film (E) is formed on the outermost surface of the B side, and the outermost surface of the A side is the center line average roughness (Ra (A )) Is 30 nm
˜1 μm, and the outermost surface on the B side has a center line average roughness (R
When a (B) is 30 nm or less and the refractive index of the coating film (A1) is nA1, the refractive index of the polymer film is nF, and the refractive index of the coating film (B1) is nB1, the following formulas (1) and ( A transparent conductive film satisfying 2). nA1 <nF and nA1 <nB1 (1) nF-0.02 <nB1 <nF + 0.02 (2) 2. The minimum value (a) of the 5 ° regular reflectance of the A surface with respect to light having a wavelength of 400 nm to 780 nm is 7% or less,
5 ° of B side for light of wavelength 400 nm to 780 nm
The standard deviation σ (a) of the 5 ° regular reflectance of the A surface with respect to the light in the range of −40 nm from the wavelength of the light giving (a) is smaller than the minimum value (b) of the regular reflectance is 0.5%. The transparent conductive film according to claim 1, which is smaller than the above. 3. The transparent conductive film according to claim 1, wherein the polymer film (F) is made of polycarbonate, polyester or a mixture thereof. 4. The polymer film according to claim 1, wherein the polymer film comprises a polymer containing a repeating unit having a fluorene skeleton, or a polymer containing the repeating unit as a copolymerization component. Transparent conductive film. 5. The polymer film has the following formula (5): [In the above formula (5), R _{1 to} R ₈ are each independently at least one group selected from a hydrogen atom, a halogen atom, and a hydrocarbon group having 1 to 6 carbon atoms. ] And the following formula (6): [In the above formula (6), R _{9 to} R ₁₆ are each independently at least one group selected from a hydrogen atom, a halogen atom and a hydrocarbon group having 1 to 6 carbon atoms, and X is 1 to 15 carbon atoms. It is a hydrocarbon group. ] Mainly composed of a copolycarbonate containing a repeating unit represented by the above formula, and the repeating unit represented by the above formula (5) is 10 to 10% of the whole.
It is 90 mol%, The transparent conductive film in any one of Claims 1-4. 6. The transparent conductive film according to claim 1, wherein the coating film (A1) contains siloxane-based resin and silicone resin fine particles as main components. 7. The transparent conductive film according to claim 1, wherein the coating film (B1) contains a crosslinked resin having a fluorene skeleton as a main component. 8. The one surface (A) of the polymer film (F).
A coating film (A1) on the surface) is laminated in the order of a fine particle-containing layer (P), a high refractive index layer (H) and a low refractive index layer (L), and (P) and (H), and (H) and (L) are in contact, and the refractive indexes of (H) and (L) are nH,
When nL and the film thickness are dH and dL, the following equations (7)-
The conditions (10) are simultaneously satisfied.
7. The transparent conductive film according to any one of 7. nL <1.5 ... (7) nH ≧ 1.5 ... (8) 90 (nm) <nLdL <180 (nm) ... (9) 90 (nm) <nHdH <360 (nm) ... (10) 9. The high refractive index layer (H) is a coating layer containing at least one oxide selected from Ti, Zr, and In as a main component, and the low refractive index layer (L) is silicon and oxygen. The transparent conductive film according to claim 8, which is a coating layer containing as a main component. 10. Si, Al, Ti, Mg, Ta, C
At least one gas barrier layer containing an inorganic material such as oxide, fluoride, nitride or oxynitride of at least one metal selected from e, In and Zr or a mixture of two or more metals is formed. The transparent conductive film according to any one of claims 1 to 9. 11. The gas barrier layer is a coating film (A
The transparent conductive film according to any one of claims 1 to 10, which is present between 1) and the polymer film (F) and / or between the coating film (B) and the transparent conductive layer (E). 12. The transparent conductive film according to claim 1, wherein a color filter layer is formed between the transparent conductive layer (E) and the coating film (B).