JP2012155291A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display device having high conductivity, transparency and a high contrast ratio.SOLUTION: The liquid crystal display device according to the present invention includes: a liquid crystal layer; a first transparent substrate and a second transparent substrate disposed facing each other via the liquid crystal layer; and a transparent conductive film disposed in the other side of the liquid crystal layer of the first transparent substrate. The transparent conductive film is formed by coating on a principal surface in the other side of the liquid crystal layer of the first transparent substrate, and the transparent conductive film includes conductive inorganic particles and a resin component. The mean particle size of the conductive inorganic particle is 30 to 180 nm, the weight content ratio of the conductive inorganic particles to the entire body of the transparent conductive film is not less than 71% and less than 85%, and a haze value of the first transparent substrate disposed with the transparent conductive film is 1.4% or less.

Description

  The present invention relates to a liquid crystal display device.

  The liquid crystal display device utilizes the characteristics such as light weight, thinness, and low power consumption, and in recent years, the market has expanded as a small display device such as various information equipment terminals and cameras, and also as a large display device such as a television. As a type of liquid crystal display device, a vertical electric field method represented by a TN (twisted nematic) type has been dominant, but recently, a liquid crystal display device called a horizontal electric field method has become mainstream. Yes.

  In a vertical electric field type liquid crystal display device, among transparent substrates disposed to face each other with a liquid crystal layer interposed therebetween, one transparent substrate is provided with a pixel electrode, and the other transparent substrate is provided with a common electrode. The liquid crystal orientation is controlled by an electric field generated between the pixel electrode and the common electrode, that is, an electric field perpendicular to the transparent substrate. On the other hand, the configuration of the horizontal electric field type liquid crystal display device includes a display electrode and a reference electrode mainly disposed on the liquid crystal layer side of one transparent substrate among the transparent substrates arranged to face each other via the liquid crystal layer. So that the light transmitted through the liquid crystal layer is modulated by controlling the orientation of the liquid crystal by an electric field generated between the display electrode and the reference electrode, that is, an electric field generated in parallel with the transparent substrate. It is a thing.

  The horizontal electric field type liquid crystal display device has the advantage of a wider viewing angle than the vertical electric field method, but as a problem that does not occur in the vertical electric field type liquid crystal display device, electrostatic influence from the outside or inside of the device In addition, there is a problem that the display quality is deteriorated such that light is lost when black is displayed due to external electromagnetic interference. This is because a horizontal electric field type liquid crystal display device has a structure in which a display electrode and a reference electrode are integrated on one transparent substrate, and therefore has a conductive layer having a shielding function against external static electricity. This is because it is not configured.

  In order to solve such problems, a conductive layer having translucency is formed on the surface opposite to the liquid crystal layer of the transparent substrate far from the backlight unit among the transparent substrates of the liquid crystal display device, Techniques for providing a shielding function have been proposed. Specifically, conductive particles are scattered in a method of forming a sputtering film made of ITO as a conductive layer, or in an adhesive material attached to a transparent substrate of a liquid crystal display device. A method for forming a conductive layer has been proposed (see Patent Document 1).

Japanese Patent No. 2758864

  However, the method of forming a conductive layer by sputtering described in Patent Document 1 requires a large vacuum device for the sputtering process, and cannot simplify the manufacturing process, which is disadvantageous in terms of manufacturing cost. is there. Further, in the method of forming a conductive layer by dispersing conductive particles in the adhesive material described in Patent Document 1, the adhesive layer is generally thick with a thickness of 10 μm or more. Transparency is reduced by the method of imparting conductivity to the layer. If the transparency of the conductive layer decreases and the haze value increases, depolarization occurs in the liquid crystal panel, and the contrast ratio decreases due to the occurrence of light leaking in the dark display and the decrease in front luminance in the bright display. There's a problem.

  The present invention solves the above problems and provides a liquid crystal display device having high conductivity, excellent transparency, and a high contrast ratio.

  In the liquid crystal display device of the present invention, the liquid crystal layer, the first transparent substrate and the second transparent substrate disposed to face each other with the liquid crystal layer interposed therebetween, and the liquid crystal layer of the first transparent substrate are: A transparent conductive film disposed on the opposite side, wherein the transparent conductive film is formed on the main surface of the first transparent substrate opposite to the liquid crystal layer by coating, The transparent conductive film contains conductive inorganic particles and a resin component, the average particle diameter of the conductive inorganic particles is 30 to 180 nm, and the weight content of the conductive inorganic particles with respect to the entire transparent conductive film is 71% or more and less than 85%, and the haze value of the first transparent substrate on which the transparent conductive film is disposed is 1.4% or less.

  According to the present invention, a liquid crystal display device having high conductivity, excellent transparency, and a high contrast ratio can be provided. In particular, a transparent conductive film having a high antistatic function and excellent transparency can be disposed directly and easily on a transparent substrate of a horizontal electric field type liquid crystal display device, and a horizontal electric field type liquid crystal display device having a high contrast ratio can be provided. .

It is a schematic cross section which shows an example of the liquid crystal display device of this invention. It is a schematic cross section explaining the measuring method of contrast ratio. It is a figure which shows the relationship between haze value and ratio A / B of contrast ratio.

  The liquid crystal display device of the present invention includes a liquid crystal layer, a first transparent substrate and a second transparent substrate that are disposed to face each other with the liquid crystal layer interposed therebetween, and the liquid crystal layer of the first transparent substrate. And a transparent conductive film disposed on the opposite side. In addition, the transparent conductive film is formed by coating on a main surface of the first transparent substrate opposite to the liquid crystal layer, and the transparent conductive film includes conductive inorganic particles and a resin component, The average particle diameter of the conductive inorganic particles is 30 to 180 nm, the weight content of the conductive inorganic particles with respect to the entire transparent conductive film is 71% or more and less than 85%, and the transparent conductive film is disposed. The first transparent substrate has a haze value of 1.4% or less.

  The liquid crystal display device of the present invention includes a liquid crystal layer, a first transparent substrate and a second transparent substrate that are disposed to face each other with the liquid crystal layer interposed therebetween, and the liquid crystal layer of the first transparent substrate. Since the transparent conductive film disposed on the opposite side is provided, the liquid crystal display device can be provided with a shielding function against electrostatic influences from outside or inside the device and external electromagnetic interference.

  In the liquid crystal display device of the present invention, the transparent conductive film is formed by coating on the main surface of the first transparent substrate opposite to the liquid crystal layer, and the transparent conductive film is conductive. Including inorganic particles and a resin component, the average particle diameter of the conductive inorganic particles is 30 to 180 nm, and the weight content of the conductive inorganic particles with respect to the entire transparent conductive film is 71% or more and less than 85%. Since the haze value of the first transparent substrate on which the transparent conductive film is disposed is 1.4% or less, a transparent conductive film having a high antistatic function and excellent transparency is used as a transparent liquid crystal display device. A liquid crystal display device that can be directly and easily disposed on a substrate and has a high contrast ratio can be provided. In particular, according to the present invention, the contrast ratio of the horizontal electric field type liquid crystal display device in which the display electrode and the reference electrode are arranged on the liquid crystal layer side of the second transparent substrate can be increased.

  In the present invention, as a result of intensive studies on the correlation between the average particle size and the weight content of the conductive inorganic particles in the transparent conductive film, the average particle size and the weight content of the conductive inorganic particles are set in the above range. Thus, a transparent conductive film having a balance between conductivity and transparency can be obtained. By using the transparent conductive film for a liquid crystal display device, a liquid crystal display device with a high contrast ratio, particularly a liquid crystal display of a horizontal electric field mode is used. Equipment can be provided.

  The average particle diameter of the conductive inorganic particles in the transparent conductive film is 30 to 180 nm, preferably 50 to 180 nm, and particularly preferably 80 to 150 nm. Here, the average particle diameter refers to the average dispersed particle diameter of the conductive inorganic particles contained in the transparent conductive film, and the unit is expressed in nanometers (nm). The average particle size is obtained by observing and measuring the particle size of each particle on the surface or cross section of the transparent conductive film with a transmission electron microscope (TEM) and then averaging the particle size of at least 100 particles. Shall. When the average particle diameter exceeds 180 nm, there arises a problem that the haze value of the coating film is excessively increased due to particle scattering. In order to reduce the average particle size of the conductive inorganic particles, it is necessary to use conductive inorganic particles having a small primary particle size. Generally, the specific surface area increases as the primary particle size of the particles decreases. Since the dispersion becomes difficult, it is substantially difficult to make the average particle diameter less than 30 nm.

  In order to set the average particle size to 30 to 180 nm, the primary particle size of the conductive inorganic particles is preferably 5 to 160 nm. Here, the primary particle size of the particles is at least after measuring and measuring the particle size of each particle separated by a grain boundary with a transmission electron microscope (TEM) using the conductive inorganic particles themselves as a sample. An average particle size obtained by averaging the particle sizes of 100 particles. When the primary particle diameter of the conductive inorganic particles is less than 5 nm, it tends to be difficult to obtain particles with good crystallinity. On the other hand, if the primary particle size is larger than 160 nm, it is difficult to make the average particle size 180 nm or less.

  The weight content of the conductive inorganic particles in the transparent conductive film relative to the entire transparent conductive film is 71% or more and less than 85%, preferably 77% or more and less than 85%, and 81% or more and less than 85%. It is particularly preferred. Here, the said weight content rate means the weight ratio with respect to the whole transparent conductive film of the conductive inorganic particle in the transparent conductive film which consists of a non-volatile solid component. When the weight content is 85% or more, not only the scattering by the particles in the transparent conductive film increases, but also the interface between the particles and air increases without filling the resin between the conductive inorganic particles, or the transparent conductive Since particles are exposed on the film surface and the surface becomes rough, the haze value of the coating film increases. Moreover, when the said weight content rate is less than 71%, since the contact between particle | grains decreases too much, the surface resistance of a transparent conductive film rises.

  The film thickness of the transparent conductive film of the present invention is preferably from 0.3 to 3.0 μm, and more preferably from 0.5 to 2.5 μm. When the film thickness is less than 0.3 μm, the light transmittance of the transparent conductive film is improved, but since the transparent conductive film is too thin, the surface resistance tends to increase and the shielding function tends to decrease. Further, when the film thickness is increased, the surface resistance tends to decrease, but when the film thickness exceeds 3.0 μm, the light transmittance tends to decrease.

  In the present invention, the transparency is indicated by a haze value, and the lower the haze value, the better the transparency. In this invention, the haze value of the said 1st transparent substrate which has arrange | positioned the said transparent conductive film can be made into 1.4% or less by using the said transparent conductive film.

  Furthermore, in the present invention, by setting the haze value to 1.4% or less, the contrast ratio in the state in which the first transparent substrate on which the transparent conductive film is disposed is disposed between two opposing polarizing plates is A. When the contrast ratio in the state where the first transparent substrate on which the transparent conductive film is not disposed is disposed between the two polarizing plates facing each other is B, the ratio A / B of the contrast ratio is 0.80 or more. can do. When the haze value is 0.9% or less, A / B can be 0.92 or more, and when the haze value is 0.8% or less, A / B can be 0.94 or more.

  Here, the contrast ratios A and B are obtained as follows. First, a transparent substrate having a transparent conductive film formed on one side is disposed between two opposing polarizing plates, and a backlight light source is disposed outside the polarizing plate disposed on the side of the transparent substrate where the transparent conductive film is not formed. Place. Next, in this state, the front luminance C1 in the state of direct Nicole and the front luminance P1 in the state of parallel Nicol are measured using a luminance meter, and the value of P1 / C1 is set as the contrast ratio A. Subsequently, using only the transparent substrate on which the transparent conductive film is not formed, the front luminance C2 in the direct Nicol state and the front luminance P2 in the parallel Nicol state are measured in the same manner as described above, and P2 / C2 Is the contrast ratio B.

The surface resistance of the transparent conductive film is preferably 1 × 10 ⁴ to 1 × 10 ¹⁴ Ω / square, and more preferably 1 × 10 ⁵ to 1 × 10 ¹² Ω / square. When the surface resistance exceeds 1 × 10 ¹⁴ Ω / square, the shielding function is lowered and it is difficult to prevent display deterioration of the liquid crystal display device. Further, when the amount of the conductive inorganic particles contained in the transparent conductive film is increased, the surface resistance is decreased, but light scattering by the conductive inorganic particles is also increased, and the haze value is increased and the transparency is decreased. Therefore, it is difficult to make the surface resistance less than 1 × 10 ⁴ Ω / square while maintaining the transparency of the transparent conductive film.

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

  The method for producing the transparent conductive film includes a step of producing a coating composition containing conductive inorganic particles and a resin component, a step of forming a coating film by applying the coating composition on a transparent substrate, And drying the coating film to form a transparent conductive film.

  The average particle diameter of the conductive inorganic particles in the coating composition is 30 to 180 nm, preferably 50 to 180 nm, and particularly preferably 80 to 150 nm. Here, the average particle diameter refers to the average dispersed particle diameter of the conductive inorganic particles dispersed in the coating composition, and the unit is expressed in nanometers (nm). The average particle diameter is defined as an average value of particle size distribution measured by a laser diffraction scattering method or a dynamic light scattering method. By setting the average particle size of the conductive inorganic particles in the coating composition to 30 to 180 nm, the average particle size of the conductive inorganic particles in the transparent conductive film formed by applying the coating composition is also set to 30 to 180 nm. be able to.

  The weight content of the conductive inorganic particles in the coating composition is 71% or more and less than 85%, preferably 77% or more and less than 85%, and particularly preferably 81% or more and less than 85%. Here, the said weight content rate means the weight ratio of the electroconductive inorganic particle with respect to the whole non-volatile solid component except a solvent. The entire transparent conductive film of conductive inorganic particles in the transparent conductive film formed by applying the coating composition by setting the weight content of the conductive inorganic particles in the coating composition to 71% or more and less than 85%. The weight content with respect to can be 71% or more and less than 85%.

  The conductive inorganic particles are not particularly limited as long as the particles have both transparency and conductivity. For example, metal particles, carbon particles, conductive metal oxide particles, conductive nitride particles, and the like are used. be able to. Among these, conductive metal oxide particles having both transparency and conductivity are preferable. Examples of the conductive metal oxide particles include tin oxide particles, antimony-containing tin oxide (ATO) particles, tin-containing indium oxide (ITO) particles, aluminum-containing zinc oxide (AZO) particles, and gallium-containing zinc oxide (GZO) particles. The metal oxide particles are mentioned. The conductive metal oxide particles may be used alone or in combination of two or more. The conductive inorganic particles preferably contain at least one selected from the group consisting of tin oxide particles, antimony-containing tin oxide particles and tin-containing indium oxide particles as a main component. This is because these compounds are excellent in transparency, conductivity, and chemical properties, and can achieve high light transmittance and conductivity even when formed into a coating film. Here, a main component means the electroconductive inorganic particle contained 70weight% or more with respect to the whole electroconductive inorganic particle.

  The resin component is not particularly limited as long as it can form a coating film by dispersing the conductive inorganic particles. For example, an acrylic resin, a polyester resin, a polyamide resin, a polycarbonate resin, a polyurethane resin, a polystyrene resin, a polyvinyl chloride resin, a polyvinylidene chloride resin, a polyvinyl alcohol resin, a polyvinyl acetate resin, and a photocurable monomer and a polymerization initiator. Examples thereof include a photocurable resin.

  The coating composition preferably further contains a solvent. Since the coating composition contains many conductive inorganic particles that are solid components, even if the resin component is a liquid component such as a photocurable monomer, the coating composition is suitable for application if it does not contain a solvent. This is because it tends to be difficult to obtain a high viscosity.

  The solvent is not particularly limited as long as it dissolves the resin component and can be removed by a drying step after coating. For example, alcohols such as ethanol, propanol and butanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diethyl ketone and cyclohexanone; ethers such as diethyl ether, tetrahydrofuran and dioxane; aromatic compounds such as benzene, toluene and xylene Glycols such as ethylene glycol, diethylene glycol and propylene glycol; glycol alkyl ethers and glycol alkyl esters such as ethylene glycol monomethyl ether and propylene glycol monomethyl ether acetate;

  The coating composition may further contain a dispersant for improving the dispersibility of the conductive inorganic particles and a surface conditioner for improving the wettability and / or leveling properties of the transparent substrate. .

  The preparation of the coating composition is not particularly limited as long as the conductive inorganic particles can be dispersed in the resin and / or solvent. For example, in order to disperse conductive inorganic particles, mechanical treatment with media such as ball mill, sand mill, pico mill, paint conditioner, or dispersion treatment using an ultrasonic disperser, homogenizer, disper, jet mill, etc. May be applied.

  Next, the coating composition is applied to a transparent substrate to form a transparent conductive film. The coating method is not particularly limited as long as it is a coating method capable of forming a smooth coating film. For example, spin coating, roll coating, die coating, air knife coating, blade coating, reverse coating, gravure coating, micro gravure coating, or other coating methods, gravure printing, screen printing, offset printing, inkjet printing, and other printing methods, spray coating, A coating method such as dip coating can be used. After applying the coating composition, the solvent is removed by drying. If necessary, the transparent conductive film may be formed by irradiating the coating film with UV light or EB light to cure the coating film. Moreover, as a transparent substrate which forms a transparent conductive film, what is necessary is just a transparent and smooth board | substrate, and it is especially preferable that it is a glass substrate.

  The liquid crystal display device of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing an example of the liquid crystal display device of the present invention.

  In FIG. 1, a liquid crystal display device 10 of the present invention includes a liquid crystal layer 11, a first transparent substrate 12a and a second transparent substrate 12b arranged to face each other with the liquid crystal layer 11 therebetween, and a first transparent substrate. The transparent conductive film 13 arrange | positioned on the opposite side to the liquid crystal layer 11 of the board | substrate 12a is provided. Although not shown, a display electrode and a reference electrode are disposed on the liquid crystal layer 11 side of the second transparent substrate 12b. Thus, the liquid crystal display device 10 constitutes a horizontal electric field type liquid crystal display device.

  The transparent conductive film 13 is formed by coating on the main surface of the first transparent substrate 12a opposite to the liquid crystal layer 11.

  Further, a polarizing plate 14a is disposed on the transparent conductive film 13, and a polarizing plate 14b is disposed outside the second transparent substrate 12b. A backlight unit 15 is disposed outside the polarizing plate 14b. Further, the liquid crystal layer 11 is sealed by a sealing portion 16.

  The liquid crystal display device 10 includes a liquid crystal layer 11, a first transparent substrate 12a and a second transparent substrate 12b arranged to face each other with the liquid crystal layer 11 therebetween, and the liquid crystal layer 11 of the first transparent substrate 12a. Includes a transparent conductive film 13 disposed on the opposite side and a display electrode and a reference electrode (not shown) disposed on the liquid crystal layer 11 side of the second transparent substrate 12b. This type of liquid crystal display device can be provided with a shield function against electrostatic influences from outside or inside the device and external electromagnetic interference. Moreover, the contrast ratio of the liquid crystal display device 10 can be increased by setting the haze value of the first transparent substrate 12a on which the transparent conductive film 13 is formed to 1.4% or less.

  Hereinafter, the present invention will be described in detail based on examples. However, the present invention is not limited to the following examples.

  First, an ITO dispersion composition was prepared as follows.

<ITO dispersion composition a>
The following components were weighed out in a 100 ml plastic bottle and dispersed with a paint shaker (Toyo Seiki Co., Ltd.) for 18 minutes, and then the zirconia beads were removed to obtain an ITO dispersion composition a. The tin content in the following tin-containing indium oxide (ITO) particles is 10% by weight.

(1) Tin-containing indium oxide (ITO) particles 12.0 g
(2) Dispersant “BYK163” (trade name, manufactured by Big Chemie) 0.60 g
(3) Methyl ethyl ketone (Wako Pure Chemical Industries, Ltd.) 13.7g
(4) Toluene (Wako Pure Chemical Industries, Ltd.) 13.7g
(5) Zirconia beads (for stirring and dispersing liquid, diameter 0.3 mm) 60.0 g

<ITO dispersion composition b, c, d>
ITO dispersion compositions b, c and d were obtained in the same manner as in the case of the ITO dispersion composition a, except that the dispersion times were 20 minutes, 25 minutes and 30 minutes, respectively.

  The average particle diameter of the ITO particles in the ITO dispersion compositions a to d was measured with a dynamic light scattering particle size distribution meter (“N4PLUS” product name, manufactured by Coulter, Inc.). Met. Moreover, when observed with a transmission electron microscope (TEM) and measuring the primary particle diameter of the raw material ITO particles, it was 32 nm. The primary particle size of the ITO particles is the result of measuring and averaging the particle size of 100 particles.

  Next, coating compositions 1 to 7 were prepared as follows.

<Coating composition 1>
The ITO dispersion composition b and the following components were weighed into a plastic bottle shielded from ultraviolet rays, and mixed and stirred to prepare 30 g of coating composition 1.

(1) ITO dispersion composition b 18.0 g
(2) Acrylic resin “BR116” (trade name, manufactured by Mitsubishi Rayon Co., Ltd.) 1.83 g
(3) Methyl ethyl ketone (Wako Pure Chemical Industries, Ltd.) 2.27g
(4) Toluene (Wako Pure Chemical Industries, Ltd.) 2.27g
(5) Cyclohexanone (Wako Pure Chemical Industries, Ltd.) 5.53 g

  The weight content of ITO particles in the non-volatile solid component of the coating composition is 72%.

<Coating compositions 2-7>
The ITO dispersion composition and other components shown in Table 1 below were blended in the blending amounts shown in Table 1, and the coating compositions 2 to 7 were prepared in the same manner as the coating composition 1, respectively. Table 1 shows the weight content of ITO particles in the nonvolatile solid components of the coating compositions 1 to 7.

Example 1
The coating composition 1 was applied on a glass substrate having a thickness of 2 mm at a rotation speed of 500 rpm using a spin coater (“1-HDX2” product name, manufactured by Mikasa), and then dried for 2 minutes with a dryer at 100 ° C. Thus, a transparent conductive film of Example 1 was obtained. As a result of observing and measuring the average particle diameter of the ITO particles in the transparent conductive film with a transmission electron microscope (TEM), it is 180 nm and is substantially the same as the average particle diameter of the ITO particles in the coating composition 1. I understood. The average particle diameter of the ITO particles is a result of measuring and averaging the particle diameters of 100 particles.

(Examples 2 to 5)
The transparent conductive films of Examples 2 to 5 were obtained in the same manner as Example 1 except that the coating compositions 2 to 5 were used, respectively.

(Comparative Examples 1-2)
Transparent conductive films of Comparative Examples 1 and 2 were obtained in the same manner as in Example 1 except that the coating compositions 6 to 7 were used, respectively.

  As a result of observing and measuring the average particle diameter of the ITO particles in the transparent conductive films of Examples 2 to 5 and Comparative Examples 1 and 2 with a transmission electron microscope (TEM), the ITO particles in each coating composition were respectively measured. It was found to be almost the same as the average particle size of.

  Next, the haze values and contrast ratios of the transparent conductive films of Examples 1 to 5 and Comparative Examples 1 and 2 were measured as follows, and the results are shown in Table 2.

(Haze value)
The haze value was measured using an ultraviolet-visible spectrophotometer “V-570” (trade name, manufactured by JASCO Corporation).

(Contrast ratio)
First, as shown in FIG. 2, a glass substrate 21 having a transparent conductive film 20 formed on one side is disposed between two opposing polarizing plates 22 and 23, and a white LED is placed outside the polarizing plate 23. The provided backlight source 24 was disposed. Although not shown, a light diffusion sheet is disposed between the polarizing plate 23 and the backlight light source 24 to provide an isotropic light source.

  Next, in this state, using a luminance meter “SR-3” (trade name) manufactured by Topcon Corporation, the front luminance C1 in the state of direct Nicole and the front luminance P1 in the state of parallel Nicol are measured, and P1 The value of / C1 was set as the contrast ratio A.

  Subsequently, using only the glass substrate 21 on which the transparent conductive film is not formed, the front luminance C2 in the direct Nicole state and the front luminance P2 in the parallel Nicol state are measured in the same manner as described above, and P2 / The value of C2 was set as the contrast ratio B.

  From the above results, the value of the contrast ratio A / B was calculated. FIG. 3 shows a relationship diagram between the haze value and the value of the contrast ratio A / B.

  As is apparent from Table 2 and FIG. 3, in Examples 1 to 5 in which the haze value is 1.4% or less, it can be seen that the contrast ratio A / B can be 0.80 or more and the contrast ratio can be increased. . On the other hand, in Comparative Examples 1 and 2 where the haze value exceeds 1.4%, the contrast ratio A / B is less than 0.80, indicating that the contrast ratio cannot be increased.

  According to the present invention, a liquid crystal display device having high conductivity, excellent transparency, and a high contrast ratio can be provided.

DESCRIPTION OF SYMBOLS 10 Liquid crystal display device 11 Liquid crystal layer 12a 1st transparent substrate 12b 2nd transparent substrate 13 Transparent electrically conductive film 14a, 14b Polarizing plate 15 Backlight unit 16 Sealing part 20 Transparent conductive film 21 Glass substrate 22, 23 Polarizing plate 24 Backlight light source

Claims (5)

A liquid crystal layer, a first transparent substrate and a second transparent substrate disposed to face each other with the liquid crystal layer interposed therebetween, and a transparent conductive layer disposed on the opposite side of the first transparent substrate from the liquid crystal layer A liquid crystal display device including a film,
The transparent conductive film is formed on the main surface of the first transparent substrate opposite to the liquid crystal layer by coating,
The transparent conductive film includes conductive inorganic particles and a resin component,
The conductive inorganic particles have an average particle size of 30 to 180 nm,
The weight content of the conductive inorganic particles with respect to the entire transparent conductive film is 71% or more and less than 85%,
A haze value of the first transparent substrate on which the transparent conductive film is disposed is 1.4% or less.   The liquid crystal display device according to claim 1, wherein the display electrode and the reference electrode are disposed on the liquid crystal layer side of the second transparent substrate.   The contrast ratio of the state in which the first transparent substrate on which the transparent conductive film is disposed is disposed between two opposing polarizing plates is A, and the first transparent substrate on which the transparent conductive film is not disposed is opposed. 3. The liquid crystal display device according to claim 1, wherein A / B is 0.80 or more, where B is a contrast ratio in a state of being disposed between the two polarizing plates.   The liquid crystal display device according to claim 1, wherein a film thickness of the transparent conductive film is 0.3 to 3.0 μm.   5. The liquid crystal display device according to claim 1, wherein the conductive inorganic particles are at least one selected from the group consisting of tin oxide particles, antimony-containing tin oxide particles, and tin-containing indium oxide particles.

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