JP2003034530A - Electrically conductive metallic oxide particles, method for producing electrically conductive metallic oxide particles, basic material with transparent electrically conductive coating, and displaying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide electrically conductive metallic oxide particles, having a low surface resistance as low as 10<2> -10<4> Ω/(square), excellent in antistaticity, antireflective property, and electromagnetic shielding property and also excellent in transparency and reliability of a coating, and capable of being used for forming a transparent electrically conductive coating. SOLUTION: The electrically conductive metallic oxide particles comprise an electrically conductive metallic oxide. The particles contain a component for improving the electric conductivity comprising one or more metallic elements selected from among Au, Ag, Pd, Pt, Rh, Ru, Cu, Fe, Ni, and Co, and have the content of the component for improving electric conductivity within the range of 0.01-1.5 wt.%, which is reduced to a metal weight. An indium oxide doped with Sn, Zn, Zr or F is preferable for the electrically conductive metallic oxide.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to conductive metal oxide particles,
The present invention relates to a coating liquid for forming a transparent conductive film in which the conductive metal oxide particles are dispersed in a polar solvent, a transparent conductive film-coated substrate, and a display device including the substrate, more specifically, antistatic property and electromagnetic shielding. A coating solution for forming a transparent conductive film, which has excellent transparency and high transparency and can be used for forming a highly reliable transparent conductive film, a substrate with a transparent conductive film, and a display provided with the substrate Regarding the device.

[0002]

2. Description of the Related Art Conventionally, for the purpose of antistatic and antireflection of the surface of a transparent substrate such as a display panel such as a cathode ray tube, a fluorescent display tube, a liquid crystal display panel, etc. It has been performed to form a transparent film having an antireflection function. Further, it is known that electromagnetic waves are emitted from a cathode ray tube and the like, and in addition to the conventional antistatic and antireflection properties, it is desired to shield these electromagnetic waves and the electromagnetic field formed by the emission of the electromagnetic waves. .

As one of the methods of shielding these electromagnetic waves and the like, there is a method of forming a conductive coating for shielding electromagnetic waves on the surface of a display panel such as a cathode ray tube. However, the conventional antistatic conductive coating has a surface resistance of at least 1.
It is sufficient to have a surface resistance of about 0 ⁷ Ω / □, whereas a conductive coating for electromagnetic shielding has a surface resistance of 10 ² to 10 ⁴ Ω /
It was necessary to have a low surface resistance such as □.

A conductive film having a low surface resistance is
If a conventional coating solution containing a conductive oxide such as Sb-doped tin oxide or Sn-doped indium oxide is used, it is necessary to make the film thicker than in the case of the conventional antistatic coating. However, since the antireflection effect is not exhibited unless the thickness of the conductive coating is set to about 10 to 200 nm, conventional conductive oxides such as Sb-doped tin oxide or Sn-doped indium oxide have a low surface resistance, There is a problem in that it is difficult to obtain a conductive coating film that is excellent in electromagnetic wave shielding properties and also in antireflection.

Further, as one of the methods for forming a conductive film having a low surface resistance, a coating film containing metal fine particles is formed on the surface of a substrate by using a coating liquid for forming a conductive film containing metal fine particles such as Ag. There is a way. In this method, as a coating liquid for forming a coating film containing metal fine particles, a colloidal metal fine particle dispersed in a polar solvent is used. In such a coating liquid, in order to improve the dispersibility of the colloidal metal fine particles, the surface of the metal fine particles is polyvinyl alcohol,
It is surface-treated with an organic stabilizer such as polyvinylpyrrolidone or gelatin. However, a conductive coating formed using such a coating solution for forming a coating containing metal fine particles has a large grain boundary resistance because the metal fine particles come into contact with each other through a stabilizer in the coating, and the surface resistance of the coating is large. Sometimes did not go down. For this reason, after film formation, it is necessary to bake at a high temperature of about 400 ° C. to decompose and remove the stabilizer, but if it is baked at a high temperature to decompose and remove the stabilizer, fusion and agglomeration of metal fine particles occur. However, there is a problem that the transparency and haze of the conductive coating are reduced. Further, in the case of a cathode ray tube or the like, there is a problem that it deteriorates when exposed to high temperature.

Further, unlike the above-mentioned conductive oxide, the metal fine particles originally do not transmit light. Therefore, the conductive coating formed by using the metal fine particles depends on the density, the film thickness, etc. of the metal fine particles in the conductive coating. There was also a problem that transparency was lowered. Further, in the conventional transparent conductive coating film containing fine metal particles such as Ag, the salt water resistance and the oxidation resistance are low, the metal is oxidized,
There is a problem that particle growth due to ionization or corrosion may occur in some cases, the conductivity and light transmittance of the coating film decrease, and the display device lacks reliability.

[0007]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art and has a low surface resistance of about 10 ² to 10 ⁴ Ω / □, antistatic property, antireflection property and electromagnetic shielding property. In addition to being excellent in transparency, the conductive metal oxide particles that can be used for forming a transparent conductive coating having excellent transparency and reliability, a coating liquid for forming a transparent conductive coating containing the fine particles, and a transparent conductive material An object of the present invention is to provide a base material with a hydrophilic coating, and a display device including the base material.

[0008]

SUMMARY OF THE INVENTION The conductive metal oxide particles according to the present invention are
Conductive metal oxide particles comprising a conductive metal oxide, wherein Au, Ag, Pd, Pt, Rh, Ru, Cu, Fe, N are contained in the particles.
It contains the conductivity improving component consisting of a metal of one or more elements selected from i and Co, and the content of the conductivity improving component in the conductive metal oxide particles is 0.
It is characterized by being in the range of 01 to 1.5% by weight.

The conductive metal oxide is preferably indium oxide doped with Sn, Zn, Zr or F. A method for producing conductive metal oxide particles, which comprises the following steps (a) to (e): (a) Conductivity improvement in a precursor (hydroxide) particle dispersion liquid of a conductive metal oxide A step of adding and mixing component fine particles,
(B) Then, a step of performing hydrothermal treatment in the range of 100 to 250 ° C., (c) a step of drying the obtained particle dispersion,
(D) 400 to 650 the powder after drying in a non-oxidizing atmosphere
Step of heat-treating in the temperature range of ° C, (e) Step of pulverizing the heat-treated powder.

The coating liquid for forming a transparent conductive film according to the present invention is characterized by comprising the above-mentioned conductive metal oxide particles and a polar solvent. The dipole moment of the polar solvent is preferably in the range of 1.6 to 5.0. The coating liquid for forming the transparent conductive film preferably contains an acid or an alkali ion.

The substrate with a transparent conductive film according to the present invention is provided with a substrate, a transparent conductive fine particle layer containing the conductive metal oxide particles on the substrate, and the transparent conductive fine particle layer. And a transparent coating having a refractive index lower than that of the transparent conductive fine particle layer. The transparent coating,
The average particle size is in the range of 5 to 300 nm and the refractive index is 1.
It is desirable to contain particles having a low refractive index of 45 or less.

The display device according to the present invention is characterized by including a front plate composed of the base material with the transparent conductive film, and the transparent conductive film being formed on the outer surface of the front plate.

[0013]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be specifically described below. Conductive Metal Oxide Particles First, the conductive metal oxide particles according to the present invention will be described. The conductive metal oxide particles according to the present invention are composed of a conductive metal oxide and a conductivity improving component.

[Conductive Metal Oxide] As the conductive metal oxide used in the present invention, the surface resistance of a transparent conductive coating film using conductive metal oxide particles obtained by adding a conductivity improving component is 10 ⁴ There is no particular limitation as long as it is Ω / □ or less, and a conventionally known conductive metal oxide can be used. By using the conductive metal oxide, a display device having excellent salt water resistance and oxidation resistance, capable of maintaining excellent display performance for a long period of time, and having excellent reliability can be obtained.

As the conductive metal oxide, tin oxide, S
Examples thereof include tin oxide doped with b, F, or P, indium oxide, indium oxide doped with Sn, Zn, Zr, or F, antimony oxide, and low-order titanium oxide. Of these, indium oxide doped with Sn, Zn, Zr or F has a low powder resistance of the obtained particles, and the obtained substrate with a transparent conductive film has a sufficient electromagnetic shielding effect and is transparent. It is desirable because it will not be hindered.

[Conductivity improving component] As the conductivity improving component used in the present invention, Au, Ag, Pd, Pt, Rh, Ru, Cu,
Examples include metals of one or more elements selected from Fe, Ni, and Co. When the metal is composed of two or more elements, it may be an alloy or a mixture. Above all,
A metal selected from Ag, Pd, Ru, and Au is preferable because the conductivity is sufficiently improved even if it is contained in the conductive metal oxide particles in a small amount.

The amount of the conductivity improving component contained in the conductive metal oxide particles is 0.0 when the conductivity improving component is converted into a metal.
It is in the range of 1 to 1.5% by weight, preferably 0.02 to 0.8% by weight. When the amount of the conductivity improving component contained in the conductive metal oxide particles is less than 0.01% by weight, the effect of including such a conductivity improving component, that is, the surface resistance of the obtained transparent conductive coating is 10%. It may not be less than ⁴ Ω / □, and the electromagnetic wave shielding effect may be insufficient.

If the amount of the conductivity improving component contained in the conductive metal oxide particles exceeds 1.5% by weight, the dispersion stability of the conductive metal oxide particles is lowered due to the excessive amount of the metal component. The conductive metal oxide particles aggregate in the liquid and the average particle diameter of the secondary particles exceeds 500 nm, which may result in insufficient conductivity of the transparent conductive coating film obtained. Moreover, the transparency of the transparent conductive coating obtained with too much metal component tends to decrease, and the salt water resistance and oxidation resistance tend to decrease.

The average particle diameter of the conductive metal oxide particles is 2 to 200 nm, preferably 5 to 150 nm. Within such a particle size range, the resistance is low,
It has excellent properties that a coating having high conductivity can be formed, the obtained coating has high film strength, excellent adhesion to a substrate, and low haze and reflectance.

The dispersed state of the conductive metal oxide and the conductivity improving component in the conductive metal oxide particles according to the present invention is not particularly limited. For example, as shown in FIG. The fine particles made of may be dispersed in the conductive metal oxide particles, and a layer made of the conductivity improving component may be formed on the entire surface or the surface of the conductive metal oxide particles. ,Moreover,
A layer made of a conductive metal oxide may be formed on the surface of the core particle made of the conductivity improving component, but the embodiment shown in FIG. 1 is particularly preferable (FIG. 1 shows a schematic sectional view of the particle). ). In the case of the particles shown in FIG. 1, the conductivity improving component may be smaller than the metal oxide particles to be formed and have a particle size of about 1 to 5 nm.

The method for producing the conductive metal oxide particles used in the present invention is the conductive metal oxide particles obtained by introducing a predetermined amount of the above-mentioned conductivity improving component into a conventionally known conductive metal oxide. Is improved and the surface resistance of the transparent conductive coating film using the conductive metal oxide particles is 10 ⁴ Ω / □ or less, and there is no particular limitation. In particular, the particles obtained by the method for producing conductive metal oxide particles according to the present invention are excellent in monodispersity, and monodispersity is maintained even in a transparent conductive film-forming coating liquid using the particles, It is preferable because a transparent conductive coating having a low haze and a sufficiently low resistance can be obtained.

Method for Producing Conductive Metal Oxide Particles Next, a method for producing the conductive metal oxide particle-dispersed sol according to the present invention will be described. The method for producing conductive metal oxide particles according to the present invention is characterized by comprising the following steps (a) to (e).

Step (a) A step of adding fine particles of a conductivity improving component to a dispersion liquid of a precursor (hydroxide) of a conductive metal oxide and mixing them. The conductive metal oxide precursor hydroxide used in the present invention is not particularly limited as long as it induces the conductive metal oxide described above, and examples thereof include tin hydroxide (hydrated tin oxide) and indium hydroxide. (Hydrated indium oxide), or tin hydroxide (hydrated tin oxide) containing F as a doping agent, Sn, Z
Indium hydroxide containing n, Zr or F (hydrated indium oxide), antimony hydroxide, etc. are preferably used.
Among them, indium hydroxide (hydrated indium oxide) containing Sn, Zn, Zr or F is preferable because a transparent conductive film having a lower resistance value can be obtained.

Such a conductive metal oxide precursor hydroxide can be prepared by a known method. For example, in the case of tin-doped indium oxide precursor hydroxide, an alkaline aqueous solution of potassium stannate is added to an aqueous solution of indium nitrate. It can be prepared by aging, washing, etc., if necessary. Next, the conductive metal oxide precursor hydroxide is dispersed in a dispersion medium such as water to prepare a dispersion liquid of the conductive metal oxide precursor hydroxide.

The concentration of the dispersion liquid of the conductive metal oxide precursor hydroxide is 1 to 30% by weight, more preferably 5 to 1% by weight as a solid content.
It is preferably in the range of 5% by weight. When the conductive metal oxide is doped with Sn, Zn, Zr or F, the amount of these dopants is 2 to 20% by weight, preferably 4 to 15% by weight in the hydroxide in terms of metal. It is desirable to be in the range.

When the solid content concentration of the dispersion is within the above range, conductive metal oxide particles capable of forming a conductive coating having a surface resistance value of 10 ⁴ Ω / □ or less can be produced.
When the solid content concentration of the dispersion liquid is less than 1% by weight, it may be because the conductivity improving component described later cannot be suitably incorporated in the conductive metal oxide precursor hydroxide, or the transparent conductive material finally obtained. The surface resistance value of the conductive coating may not be 10 ⁴ Ω / □ or less, and thus a sufficient electromagnetic wave shielding effect may not be obtained. Also, the solid content concentration of the dispersion is 3
If it exceeds 0% by weight, the obtained conductive metal oxide particles may aggregate or the average particle diameter may exceed 200 nm depending on the conditions, and in this case as well, the surface resistance value of the finally obtained transparent conductive film. May not be less than 10 ⁴ Ω / □, and thus a sufficient electromagnetic wave shielding effect may not be obtained.

A conductivity improving component is added to the dispersion liquid of the conductive metal oxide precursor hydroxide. Examples of the conductivity improving component used in the present invention are the same as those described above. Particularly, one or more metals or two or more alloys selected from Ag, Pd, Ru, Au, and Pt are preferable because the conductivity is sufficiently improved even when the conductive metal oxide particles are contained in a small amount.

In the present invention, a metal colloid composed of these metals (including alloys) can be preferably used. Such a metal colloid can be obtained by a conventionally known method, for example, a method of adding a reducing agent to an aqueous solution of a metal salt such as silver nitrate for reduction, or irradiating with ultrasonic waves to reduce the particle diameter to about A metal colloid of about 1 to 50 nm can be obtained.

The amount of the conductivity improving component added is such that the amount of the conductivity improving component contained in the conductive metal oxide particles is calculated by converting the conductive metal oxide precursor hydroxide into an oxide. Is added so as to be in the range of 0.01 to 1.5% by weight, preferably 0.02 to 0.8% by weight, calculated as metal. When the amount of the conductivity improving component contained in the conductive metal oxide particles is less than 0.01% by weight, the effect of including such a conductivity improving component, that is, the surface resistance of the obtained transparent conductive coating is 10%. It may not be less than ⁴ Ω / □, and the electromagnetic wave shielding effect may be insufficient.

When the amount of the conductivity improving component contained in the conductive metal oxide particles exceeds 1.5% by weight, the dispersion stability of the conductive metal oxide particles is lowered due to too much metal component, and for example, coating is performed. The conductive metal oxide particles aggregate in the liquid and the average particle diameter of the secondary particles exceeds 500 nm, which may result in insufficient conductivity of the transparent conductive coating film obtained. Moreover, the transparency of the transparent conductive coating obtained with too much metal component tends to decrease, and the salt water resistance and oxidation resistance tend to decrease.

Then, the conductivity improving component is added to the dispersion liquid of the conductive metal oxide precursor hydroxide and then mixed. The mixing method is not particularly limited, but ultrasonic irradiation is preferable. Irradiation with ultrasonic waves promotes monodispersion of aggregates of the conductive metal oxide precursor hydroxide. Although the reason is not always clear, the effect of adding the conductivity improving component may not be obtained without irradiation of ultrasonic waves. Ultrasound intensity is 20 ~ 400kH
It suffices that z be in the range of 10 to 600 W.

Step (b) Next, 100 to 250 of the dispersion liquid obtained in the step (a) is added.
Hydrothermal treatment is performed at a temperature of 120 ° C, preferably 120 to 220 ° C. By performing hydrothermal treatment at such a temperature, the conductivity improving component is incorporated into the conductive metal oxide particles, and particles having low surface resistance can be obtained. The hydrothermal treatment temperature is 100
If the temperature is lower than ℃, the incorporation of the conductivity improving component is insufficient and the surface resistance of the obtained transparent conductive film is 10 ⁴ Ω / □.
The following may not occur, and the electromagnetic shielding effect of the transparent conductive film may be insufficient. Hydrothermal treatment temperature is 25
If it exceeds 0 ° C., the doping agent such as Sn, Zn, Zr or F becomes difficult to be doped, and the surface resistance may not be lowered.

Usually, such hydrothermal treatment is preferably carried out in a pressure resistant container such as an autoclave. Step (c) The hydrothermally treated dispersion liquid of the conductive metal oxide precursor hydroxide is dried. For drying, spray drying such as spraying is preferably adopted. The drying temperature is not particularly limited and may be room temperature (20
(° C) to 250 ° C.

By drying in this manner, it is possible to stably obtain conductive metal oxide particles having a low resistance. The water content in the powder after drying varies depending on the type of the conductivity improving component, the particle size, etc., but is preferably about 20% by weight or less. Step (d) drying the conductive metal oxide precursor hydroxide powder obtained by drying, in a non-oxidizing atmosphere such as an inert gas, a reducing gas, or a vacuum,
Heat treatment is performed at 400 to 650 ° C.

If the heat treatment temperature is within the above range, conductivity
Conductive with high conductivity due to crystallization of the conductive metal oxide component
Metal oxide particles can be obtained. In addition, heat treatment
When the temperature was lower than 400 ° C, the crystallization was insufficient.
, The doping effect is not fully exerted, and heat treatment
Conductive metal oxide obtained when the temperature exceeds 650 ° C
The particles may sinter, or the particles may fuse together.
As a result, the haze of the obtained transparent conductive film was increased.
The conductivity improving component is oxidized and the surface resistance is 10 ^FourΩ /
□ May not fall below.

The heat treatment in the above temperature range transforms the conductive metal oxide precursor hydroxide into a crystalline conductive metal oxide. Since the conductive metal oxide particles according to the present invention include the conductivity improving component, they have higher conductivity than particles made of only the conductive metal oxide. Step (e) The powder after the heat treatment thus obtained is pulverized. The pulverization may be dry pulverization or wet pulverization, but wet pulverization is particularly preferable because it can be uniformly pulverized. When performing wet pulverization, the conductive metal oxide particles are dispersed in water and an organic solvent. By doing so, a conductive metal oxide particle dispersed sol is prepared.

Since the heat-treated powder is often agglomerated and may not be easily dispersed, the agglomerate may be crushed if necessary. A water and / or organic solvent dispersion of the heat-treated powder is prepared. The concentration of the powder at this time is preferably in the range of 10 to 40% by weight. If the concentration of the powder dispersion is less than 10% by weight,
The pulverization efficiency is low, and the concentration may be too low for use in the coating liquid for forming a transparent conductive film described later. Further, for this reason, concentration may be required. When the concentration of the powder dispersion exceeds 40% by weight, the viscosity of the obtained sol may be too high or the stability may be insufficient.

The organic solvent may be the same as the polar solvent exemplified in the coating liquid described later. If necessary, a dispersion accelerator may be added to the dispersion liquid. Examples of the dispersion accelerator include mineral acids such as nitric acid, hydrochloric acid and sulfuric acid, organic acids such as acetic acid and formic acid, and alkalis such as potassium hydroxide and sodium hydroxide.

The amount of the dispersant added at this time is preferably in the range of 0.5 to 10 parts by weight with respect to 100 parts by weight of the conductive metal oxide particles. When an acid is used as the dispersion accelerator, it is preferable to adjust the pH of the dispersion so as to be in the range of 2.5 to 5.0, and when an alkali is used, the pH of the dispersion is 9.0 to 9.0. It is preferable to adjust the range to be 12.0.

The dispersion liquid of the powder thus added with the dispersion accelerator is subjected to wet pulverization. The pulverization method at this time is not particularly limited as long as the average particle diameter after pulverization can be in the range of 2 to 200 nm, and a conventionally known method can be adopted. For example, it can be pulverized by a sand mill, colloid mill, ball mill, ultrasonic homogenizer, vent shaker or the like.

The conductive metal oxide particle-dispersed sol thus obtained is concentrated or diluted as necessary so that the conductive metal oxide particle concentration is 10 to 40% by weight, preferably 15 to 30.
It can be adjusted in the range of weight%. The average particle diameter of the conductive metal oxide particles obtained as described above is 2 to 2
It is in the range of 00 nm.

Coating Liquid for Forming Transparent Conductive Film Next, the coating liquid for forming the transparent conductive film according to the present invention will be described. The coating liquid for forming a transparent conductive film according to the present invention comprises the above-mentioned conductive metal oxide particles and a polar solvent. [Conductive Metal Oxide Particles] As the conductive metal oxide particles, the same conductive metal oxide particles as described above can be used.

[Polar Solvent] The polar solvent used in the present invention includes water; methanol, ethanol, propanol,
Alcohols such as butanol, diacetone alcohol, furfuryl alcohol, tetrahydrofurfuryl alcohol, ethylene glycol, hexylene glycol, isopropyl glycol; esters such as acetic acid methyl ester, acetic acid ethyl ester; diethyl ether, ethylene glycol monomethyl ether, ethylene Examples include ethers such as glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether; ketones such as acetone, methyl ethyl ketone, acetylacetone, and acetoacetic acid ester. These may be used alone or in combination of two or more.

The polar solvent has a dipole moment of 1.6.
It is preferably in the range of to 5.0. If the dipole moment of the polar solvent is less than 1.6, the monodispersity and dispersion stability of the metal oxide particles in the coating solution may be insufficient, resulting in a dense conductive metal oxide particle layer. May not be formed, or the haze of the obtained transparent conductive film may be increased.

A polar solvent having a dipole moment of more than 5.0 is usually difficult to obtain, and the monodispersity and dispersion stability of the metal oxide particles in the coating solution are not improved. . As the organic solvent preferably used in the present invention, water; alcohols such as methanol, ethanol, propanol, butanol, diacetone alcohol, furfuryl alcohol, tetrahydrofurfuryl alcohol, ethylene glycol and isopropyl glycol;
Esters such as acetic acid methyl ester, acetic acid ethyl ester; diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether,
Examples thereof include ethers such as ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether; ketones such as acetone, methyl ethyl ketone, and acetoacetic acid ester.

The coating liquid of the present invention may contain a dispersion accelerator such as the above-mentioned acid or alkali. When an acid is used as the dispersion accelerator, the pH of the dispersion is 2.5 to 5.
It is preferable to adjust the pH to be in the range of 0, and it is preferable to adjust the pH of the dispersion to be in the range of 9.0 to 12.0 when an alkali is used.

The coating liquid for forming a transparent conductive film according to the present invention contains conductive metal oxide particles in an amount of 0.1 to 7% by weight, preferably 0.5 to 5% by weight. Is desirable. If the content of the conductive metal oxide particles in the coating liquid for forming the transparent conductive coating film is less than 0.1% by weight, the film thickness of the coating film obtained may be small, and thus sufficient conductivity cannot be obtained. Sometimes. If the conductive metal oxide particles exceed 7% by weight, the conductive metal oxide particles may aggregate in the coating liquid to form secondary particles. The average particle diameter of the secondary particles is 500 nm. If it exceeds the above range, sufficient conductivity may not be obtained, and the coating itself may become thick, resulting in a decrease in light transmittance and deterioration in transparency or a deterioration in appearance.

The coating liquid for forming the transparent conductive film may contain fine particle carbon, a dye, a pigment, etc., if necessary. When fine particle carbon is blended, fine particle carbon having an average particle diameter of 2 to 200 nm, preferably 2 to 150 nm is preferable. Further, the blending amount of the particulate carbon is preferably 0.15 parts by weight or less with respect to 100 parts by weight of the conductive metal oxide particles. When the blending amount of the particulate carbon is 0.15 parts by weight or less, the transmittance can be adjusted without significantly lowering the conductivity of the transparent conductive coating, and the contrast can be improved.

The coating liquid for forming a transparent conductive film according to the present invention may contain a matrix-forming component which acts as a binder for the conductive particles after the film is formed. Such a matrix-forming component is preferably made of silica, specifically, a silicic acid obtained by dealkalizing a hydrolyzed polycondensate of an organosilicon compound such as alkoxysilane or an alkali metal silicate aqueous solution. Examples thereof include polycondensates and coating resins. If the matrix-forming component is contained in an amount of 0.01 to 0.5 parts by weight, preferably 0.03 to 0.3 parts by weight, as a solid content per 1 part by weight of the conductive metal oxide particles. Good.

Solid content concentration in the coating liquid for forming the transparent conductive film (conductive metal oxide particles and additives such as conductive fine particles other than conductive metal oxide particles, if necessary, additives such as dyes and pigments) From the viewpoint of fluidity of the liquid and dispersibility of particulate components such as composite metal fine particles in the coating liquid, it is preferably 15% by weight or less, preferably 0.15 to 5% by weight.

In the coating liquid for forming a transparent conductive film according to the present invention, the metal oxide particles according to the present invention are dispersed in an organic solvent by a known method, and if necessary, a matrix-forming component is added. It can be prepared by mixing other conductive fine particles, dyes, pigments and the like. It can also be prepared by mixing the above-mentioned metal oxide particle-dispersed sol with a matrix-forming component, other conductive fine particles, a dye, and a pigment, and adjusting the concentration as necessary.

Substrate with Transparent Conductive Film Next, the substrate with a transparent conductive film according to the present invention will be specifically described. In the substrate with a transparent conductive film according to the present invention, the above-mentioned average particle size is 5 to 500 nm, preferably 10 to 10 on a substrate such as a film, sheet or other molded body made of glass, plastic, ceramic or the like. A transparent conductive fine particle layer made of 300 nm conductive metal oxide particles, and a transparent coating film is formed on the transparent conductive fine particle layer.

Examples of the conductive metal oxide particles are the same as those mentioned above. [Transparent conductive fine particle layer] The film thickness of the transparent conductive fine particle layer is
The thickness is preferably in the range of 50 to 500 nm, preferably 50 to 300 nm, and if the thickness is in this range, it is possible to obtain a transparent conductive film-coated substrate having an excellent electromagnetic shielding effect.

If necessary, such a transparent conductive fine particle layer may contain metal fine particles other than the above conductive metal oxide particles, a matrix component, an organic stabilizer, and the like. , And the same as the above. [Transparent coating] In the substrate with a transparent conductive coating according to the present invention,
A transparent coating having a refractive index lower than that of the transparent conductive fine particle layer is formed on the transparent conductive fine particle layer.

The thickness of the transparent coating film at this time is 50 to 30.
It is preferably in the range of 0 nm, preferably 80 to 200 nm. When the thickness of the transparent film is less than 50 nm,
The strength and antireflection performance of the film may be poor. If the film thickness of the transparent film exceeds 300 nm, cracks may occur in the film or the strength of the film may decrease, and the film may be too thick and the antireflection performance may be insufficient.

Such a transparent film is formed of, for example, an inorganic oxide such as silica, titania, zirconia, or a composite oxide thereof. In the present invention, the transparent coating is preferably a silica-based coating made of a hydrolyzed polycondensate of a hydrolyzable organosilicon compound or a silicic acid polycondensate obtained by dealkalizing an aqueous alkali metal silicate solution. The transparent conductive film-coated substrate having such a transparent film formed thereon has excellent antireflection performance.

The transparent coating has an average particle size of 5
It is desirable to include particles having a low refractive index in the range of ˜300 nm, preferably 10 to 200 nm and having a refractive index of 1.45 or less, preferably 1.40 or less. The average particle size of the low refractive index particles used is appropriately selected according to the thickness of the transparent coating formed.

When the refractive index of the low refractive index particles is 1.45 or less, the resulting transparent conductive film-coated substrate has low bottom reflectance and luminous reflectance, and exhibits excellent antireflection performance. You can The content of low refractive index particles in the transparent coating is 10 to 90% by weight, preferably 20 in terms of oxide.
It is desirable to be in the range of -80% by weight.

The low refractive index particles used in the present invention are not particularly limited as long as the average particle diameter and the refractive index are within the above ranges, and conventionally known particles can be used. Examples of such low refractive index particles include particles composed of metal oxides such as silica, alumina, silica-alumina and zirconia. Also, the composite oxide sol disclosed in Japanese Patent Application Laid-Open No. 7-133105 filed by the applicant of the present application,
Porous composite oxide particles having a coating layer disclosed in WO00 / 37359, and Japanese Patent Application No. 2000-482.
The silica-based fine particles proposed in No. 77 have a refractive index of 1.4.
It is as low as 0 or less, and the transparent low-reflection conductive film-coated substrate obtained by using such silica fine particles has excellent antireflection performance and low luminous reflectance, and therefore the reflection (reflection) felt by the eye It is preferable because it is weak and the coloring of the reflection color can be suppressed.

Further, if necessary, the transparent film may contain additives such as fine particles, dyes and pigments, which are made of a low refractive index material such as magnesium fluoride. [Manufacturing Method of Substrate with Transparent Conductive Coating] Next, a manufacturing method of the above-mentioned base material with a transparent conductive coating will be described. The substrate with a transparent conductive coating is formed by coating and drying a coating liquid for forming a transparent conductive coating containing the above-mentioned conductive metal oxide particles on a substrate to form a transparent conductive fine particle layer, and then the fine particles. It can be manufactured by applying a coating liquid for forming a transparent film on the layer to form a transparent film having a refractive index lower than that of the fine particle layer on the transparent conductive fine particle layer. [Formation of transparent conductive fine particle layer] First, the transparent conductive film forming coating solution is applied onto a substrate and dried to form a transparent conductive fine particle layer on the substrate.

The method for forming the transparent conductive fine particle layer is, for example, a dipping method, a spinner method, a spray method, a roll coater method using a coating solution for forming a transparent conductive film.
After applying it on the substrate by a method such as flexographic printing,
Dry at a temperature ranging from room temperature to about 90 ° C. When the coating liquid for forming the transparent conductive film contains the above-mentioned matrix-forming component, the matrix-forming component may be cured.

For example, a film formed by applying a coating liquid for forming a transparent conductive film is dried at the time of drying or after drying.
Even if it is heated at 50 ° C or higher, or the uncured film is irradiated with electromagnetic waves such as ultraviolet rays, electron rays, X-rays, and γ rays having a wavelength shorter than visible light, or exposed to an atmosphere of active gas such as ammonia. Good. By doing so, the hardening of the film-forming component is promoted, and the hardness of the film obtained is increased.

The thickness of the transparent conductive fine particle layer formed by the above method is preferably in the range of about 50 to 500 nm, more preferably 50 to 300 nm. If the thickness is in this range, the antistatic property and the electromagnetic shielding will be improved. It is possible to obtain a substrate with a transparent conductive coating having excellent properties. [Formation of transparent coating] In the present invention, a transparent coating having a refractive index lower than that of the fine particle layer is formed on the transparent conductive fine particle layer formed as described above.

The thickness of the transparent coating is preferably in the range of 50 to 300 nm, preferably 80 to 200 nm, and in such a range, excellent antireflection property is exhibited. The method for forming the transparent coating is not particularly limited, and depending on the material of the transparent coating, a dry thin film forming method such as a vacuum evaporation method, a sputtering method, an ion plating method, or a dipping method or a spinner method as described above. A wet thin film forming method such as a spray method, a roll coater method, or a flexographic printing method can be used.

When forming the above-mentioned transparent film by the wet thin film forming method, a conventionally known coating liquid for forming a transparent film can be used. As such a transparent film forming coating solution,
Specifically, a coating liquid containing an inorganic oxide such as silica, titania or zirconia, or a composite oxide of these as a transparent film forming component is used. In the present invention, as a coating liquid for forming a transparent film, a hydrolytic polycondensate of a hydrolyzable organosilicon compound, or a silica-based transparent film forming coating containing a silicic acid solution obtained by dealkalizing an aqueous alkali metal silicate solution. The liquid is preferable, and it is particularly preferable that the liquid contains a hydrolytic polycondensate of an alkoxysilane represented by the following general formula [1]. The silica-based coating formed from such a coating solution has a smaller refractive index than the conductive fine particle layer containing conductive metal oxide particles, and the obtained transparent coated substrate has excellent antireflection properties.

R _a Si (OR ') _4-a [1] (In the formula, R is a vinyl group, an aryl group, an acryl group, an alkyl group having 1 to 8 carbon atoms, a hydrogen atom or a halogen atom, and R' vinyl group, an aryl group, an acrylic group, an alkyl group of carbon-based number _{1~8, -C 2 H 4 OC n} H 2n + 1 (n = 1
To 4) or a hydrogen atom, and a is an integer of 1 to 3. ) Such alkoxylanes include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraoctylsilane,
Examples thereof include methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, methyltriisopropoxysilane, vinyltrimethoxysilane, phenyltrimethoxysilane and dimethyldimethoxysilane.

When one or more of the above alkoxysilanes are hydrolyzed in the presence of an acid catalyst in, for example, a water-alcohol mixed solvent, a coating liquid for forming a transparent film containing a hydrolyzed polycondensate of alkoxysilane. Is obtained. The concentration of the film forming component contained in such a coating liquid is preferably 0.5 to 2.0% by weight in terms of oxide. The coating liquid for forming a transparent film used in the present invention has an average particle size of 5 to 300 nm, preferably 10 to 200 nm and a refractive index of 1.45 or less, preferably 1.40 or less. It is desirable to include particles.

The average particle size of the low refractive index particles used is
It is appropriately selected according to the thickness of the transparent coating formed. If the low refractive index particles used have a refractive index of 1.45 or less, the resulting transparent conductive film-coated substrate has low bottom reflectance and luminous reflectance, and exhibits excellent antireflection performance. can do.

The amount of the low-refractive-index particles used is such that the content of the low-refractive-index particles in the transparent coating is in the range of 10 to 90% by weight, preferably 20 to 80% by weight, calculated as oxide. It is desirable to use. The low refractive index particles used in the present invention are not particularly limited as long as the average particle diameter and the refractive index are within the above ranges, and conventionally known particles can be used, for example, those described above are used.

Furthermore, the coating liquid for forming a transparent film used in the present invention contains fine particles composed of a low refractive index material such as magnesium fluoride, and a small amount so as not to impair the transparency and antireflection performance of the transparent film. The conductive fine particles and / or an additive such as a dye or a pigment may be included. In the present invention, a coating film formed by applying such a coating liquid for forming a transparent film is dried at the time of drying or after drying.
Even if it is heated at 50 ° C or higher, or the uncured film is irradiated with electromagnetic waves such as ultraviolet rays, electron rays, X-rays, and γ rays having a wavelength shorter than visible light, or exposed to an atmosphere of active gas such as ammonia. Good. By doing so, the hardening of the film-forming component is accelerated, and the hardness of the obtained transparent film is increased.

Further, when the transparent coating film-forming coating liquid is applied to form a coating film, the transparent conductive fine particle layer is coated with about 40 to 9 parts.
While maintaining the temperature at 0 ° C, apply the coating liquid for forming a transparent film,
When the above-mentioned treatment is carried out, ring-shaped irregularities are formed on the surface of the transparent film, and an antiglare transparent film-coated substrate with less glare can be obtained. Display Device The substrate with a transparent conductive film according to the present invention has a surface resistance in the range of approximately 10 ² to 10 ⁴ Ω / □ required for electromagnetic shielding, is excellent in transparency, and is in the visible light region and near red. It has sufficient antireflection performance in the outer region and is suitably used as a front plate of a display device.

The display device according to the present invention comprises a cathode ray tube (C
RT), a fluorescent display tube (FIP), a plasma display (PDP), a liquid crystal display (LCD), and the like, which is an apparatus for electrically displaying an image, and is composed of the transparent conductive film-coated substrate as described above. It has a front plate.
When a conventional display device having a front plate is operated, an image is displayed on the front plate and electromagnetic waves are emitted from the front plate at the same time, and the electromagnetic waves affect the human body of an observer. In the device, the front plate is approximately 10 ² to
Since it is composed of a transparent conductive film-coated substrate having a surface resistance of 10 ⁴ Ω / □, it is possible to effectively shield the electromagnetic field and the electromagnetic field generated by the emission of the electromagnetic wave. .

Further, when reflected light is generated on the front plate of the display device, the reflected light makes it difficult to see the display image. However, in the display device according to the present invention, the front plate is sufficient in the visible light region and the near infrared region. Since the substrate is provided with a transparent conductive coating having antireflection performance, such reflected light can be effectively prevented. Furthermore, the front plate of the cathode ray tube is composed of the transparent conductive film-coated substrate according to the present invention,
When a small amount of a dye or pigment is contained in at least one of the transparent conductive fine particle layer and the transparent coating formed on the transparent conductive coating, these dyes or pigments each have a unique wavelength. Of light, which can improve the contrast of the display image projected from the cathode ray tube.

[0074]

EFFECTS OF THE INVENTION According to the present invention, the antistatic property and the electromagnetic shielding property are excellent, the transparency is excellent and the light transmittance can be controlled, and the salt water resistance and the oxidation resistance are excellent and the reliability is high. It is possible to obtain conductive metal oxide particles that are composed of a conductive metal oxide component and a conductivity improving component that can be suitably used for a substrate having a transparent conductive coating.

When a transparent conductive fine particle layer is formed using the coating liquid for forming a transparent conductive fine film containing such conductive metal oxide particles, and a transparent coating is formed on the transparent conductive fine particle layer. It is possible to provide a highly reliable substrate with a transparent conductive film, which has excellent antireflection properties and has a small decrease in transparency. Furthermore, when such a substrate with a transparent conductive film having excellent transparency is used as a front plate of a display device, it is possible to provide a display device having excellent electromagnetic shielding properties and antireflection properties.

[0076]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0077]

Example 1 Conductive metal oxide particle (P-1) dispersion sol
Preparation Step (a) A solution obtained by dissolving 79.9 g of indium nitrate in 686 g of water and 12.7 g of potassium stannate at a concentration of 10% by weight.
And a solution obtained by dissolving it in a potassium hydroxide solution of 1. were prepared, and these solutions were added to 1000 g of pure water kept at 50 ° C. over 2 hours. During this period, the pH of the system is set to 1
It was held at 1. The Sn-doped indium oxide hydrate is filtered from the obtained Sn-doped indium oxide hydrate dispersion.
After washing, disperse in water again to obtain a solid content of 10% by weight.
A metal oxide precursor hydroxide dispersion liquid (A) was prepared.

Separately, a silver fine particle dispersion liquid was prepared as follows. To 100 g of pure water, trisodium citrate was added in advance so as to be 0.01 part by weight per 1 part by weight of silver metal, and silver nitrate was added to this so that the concentration would be 10% by weight in terms of metal. An aqueous solution of ferrous sulfate having the same number as the number of the same was added and stirred under a nitrogen atmosphere for 1 hour to obtain a dispersion liquid of silver fine particles. The obtained dispersion liquid was washed with a centrifugal separator to remove impurities and then dispersed in water to prepare a silver fine particle (M-1) dispersion liquid having a concentration of 4% by weight. The average particle size of the silver fine particles (M-1) was 20 nm.

Then, 100 g of the metal oxide precursor hydroxide dispersion (A) was adjusted so that the content of silver in the conductive metal oxide particles (that is, as oxide) was 0.05% by weight. Silver fine particle (M-1) dispersion 0.125 as improving component
Ultrasonic wave generator (Kaijo Electric Co., Ltd .: AUTO)
CHEDER-300, type-5271) was irradiated with ultrasonic waves of 27 kHz and 300 W.

Step (b) The ultrasonic-irradiated dispersion was placed in a pressure vessel and hydrothermally treated at 200 ° C. for 2 hours. Step (c) The hydrothermally treated dispersion was spray-dried at a temperature of 100 ° C. to prepare a metal oxide precursor hydroxide powder.

Step (d) The above powder was heat-treated at 550 ° C. for 2 hours in a nitrogen gas atmosphere. Step (e) This was dispersed in ethanol to a concentration of 30% by weight, and the pH was adjusted to 3.5 with an aqueous nitric acid solution.
While keeping this mixture at 30 ° C, use a sand mill to add 0.5.
A sol was prepared by crushing for an hour. Next, ethanol was added to prepare a conductive metal oxide (tin-doped indium oxide containing silver) particles (P-1) dispersed sol having a concentration of 20% by weight.

With respect to the obtained conductive metal oxide particles (P-1), SEM photographs were taken, the particle diameters of 20 particles were measured, and this average value was taken as the average particle diameter. The results are shown in Table 1.
Shown in.

[0083]

[Example 2] Conductive metal oxide particle (P-2) dispersion sol
In Preparation Example 1, except that 0.25 g of the silver fine particle (M-1) dispersion liquid was added as the conductivity improving component so that the content of silver in the conductive metal oxide particles was 0.1% by weight. In the same manner as in Example 1, a conductive metal oxide particle (P-2) dispersed sol having a concentration of 20% by weight was prepared.

Table 1 shows each average particle size of the obtained conductive metal oxide particles (P-2).

[0085]

[Example 3] Conductive metal oxide particle (P-3) dispersion sol
In Preparation Example 1, except that 2.5 g of the silver fine particle (M-1) dispersion liquid was added as the conductivity improving component so that the content of silver in the conductive metal oxide particles was 1.0% by weight. Example 1
A conductive metal oxide particle (P-3) dispersed sol having a concentration of 20% by weight was prepared in the same manner as in.

Table 1 shows the average particle diameters of the obtained conductive metal oxide particles (P-3).

[0087]

[Example 4] Conductive metal oxide particle (P-4) dispersion sol
Preparation Silver and palladium alloy fine particles (M-2) as follows
A dispersion was prepared. To 100 g of pure water, trisodium citrate was added in advance so as to be 0.01 parts by weight per 1 part by weight of the total metal of silver and palladium, and the concentration became 10% by weight in terms of metal. So that the ratio becomes 7/3, silver nitrate and palladium nitrate aqueous solutions are added, and further an aqueous solution of ferrous sulfate in an amount equal to the total molar number of silver nitrate and palladium nitrate is added, and the mixture is stirred under a nitrogen atmosphere for 1 hour to obtain silver. A dispersion of fine alloy particles of palladium and palladium was obtained. The resulting dispersion was washed with water by a centrifuge to remove impurities, and then dispersed in water to prepare a silver-palladium alloy fine particle (M-2) dispersion having a concentration of 4% by weight. The average particle diameter of the alloy fine particles (M-2) was 20 nm.

Then, a conductive metal oxide particle (P-4) -dispersed sol having a concentration of 20% by weight was prepared in the same manner as in Example 2 except that the alloy fine particle (M-2) dispersion was used.

[0089]

Example 5 Conductive Metal Oxide Particle (P-5) Dispersion Sol
Preparation A gold fine particle (M-3) dispersion was prepared as follows.
Methanol / water mixed solvent (methanol 40 parts by weight / 60
Polyvinyl alcohol is added to 0.01 part by weight per 1 part by weight of gold, and chloroauric acid is added so that the concentration of the fine gold particles in the dispersion becomes 2% by weight in terms of metal. Then, the mixture was heated in a flask equipped with a reflux condenser at 90 ° C. for 5 hours in a nitrogen atmosphere to prepare a gold fine particle (M-3) dispersion liquid having a concentration of 4% by weight. The average particle size of the gold fine particles (M-3) was 20 nm.

Then, a conductive metal oxide particle (P-5) -dispersed sol having a concentration of 20% by weight was prepared in the same manner as in Example 2 except that this gold fine particle (M-3) dispersion was used.

[0091]

[Comparative Example 1] Conductive metal oxide particle (P-6) dispersion sol
Preparation A solution obtained by dissolving 79.9 g of indium nitrate in 686 g of water and 12.7 g of potassium stannate at a concentration of 10% by weight.
And a solution obtained by dissolving it in a potassium hydroxide solution of 1. were prepared, and these solutions were added to 1000 g of pure water kept at 50 ° C. over 2 hours. During this period, the pH of the system is set to 1
It was held at 1. The Sn-doped indium oxide hydrate is filtered from the obtained Sn-doped indium oxide hydrate dispersion.
After washing, it was dried, and then calcined in air at a temperature of 350 ° C. for 3 hours, and further in air at a temperature of 600 ° C. for 2 hours to obtain Sn-doped indium oxide fine particles. This was dispersed in pure water to a concentration of 30% by weight, and the pH was adjusted to 3.5 with a nitric acid aqueous solution.
While maintaining this mixed solution at 30 ° C., the mixture was ground for 3 hours to prepare a sol. Next, this sol was treated with an ion exchange resin to remove nitrate ions, and pure water was added to prepare a conductive metal oxide particle (P-6) -dispersed sol having a concentration of 20% by weight.

[0092]

[Comparative Example 2] Conductive metal oxide particle (P-7) dispersion sol
In Preparation Example 1, except that 12.5 g of the silver fine particle (M-1) dispersion liquid was added as the conductivity improving component so that the content of silver in the conductive metal oxide particles would be 5.0% by weight. In the same manner as in Example 1, a conductive metal oxide particle (P-7) -dispersed sol having a concentration of 20% by weight was prepared.

[0093]

[Comparative Example 3] Conductive metal oxide particle (P-8) dispersion sol
Preparation The conductive metal oxide particles (P-6) dispersion sol prepared in Comparative Example 1 and the silver fine particle (M-1) dispersion prepared in Example 1 were mixed with conductive metal oxide particles (P-6). ) And silver fine particles (M-1) were mixed at a solid content weight ratio of 95/5 to prepare a conductive metal oxide particle (P-8) -dispersed sol having a concentration of 20% by weight.

[0094]

[Table 1]

[0095]

Examples 6 to 12 and Comparative Examples 4 to 7 a) Transparent conductive coating
Preparation of coating liquids (C-1) to (C-7) and (C-8) to (C-11) for forming 50 g of ethyl orthosilicate (SiO ₂ : 28% by weight), 194.6 g of ethanol, 1 of concentrated nitric acid A mixed solution of 0.4 g and pure water 34 g was stirred at room temperature for 5 hours to prepare a liquid (A) containing a matrix-forming component having a SiO ₂ concentration of 5% by weight.

The dispersion sol of (P-1) to (P-8) and the dispersion of (M-1) shown in Table 1 and the above matrix-forming component are contained.
Coating liquids (C-1) to (C-11) for forming a transparent conductive film shown in Table 2 were prepared from liquid (A), water, t-butanol, butyl cellosolve, citric acid and N-methyl-2-pyrrolidone. Prepared. b) Preparation of coating liquid (B) for forming a transparent film Preparation of low refractive index particles (particles that are hollow inside the outer shell layer
Child) A reaction mother liquor is prepared by mixing 10 g of silica sol having an average particle diameter of 5 nm and a SiO ₂ concentration of 20% by weight with 190 g of pure water.
Warmed to 95 ° C. The pH of this reaction mother liquor was 10.5, and 24,900 g of a 1.5 wt% sodium silicate aqueous solution as SiO ₂ and 0.5 as Al ₂ O ₃ were added to the mother liquor.
A 36% by weight aqueous solution of sodium aluminate of 36,800 g was added at the same time. During that time, the temperature of the reaction solution was maintained at 95 ° C. The pH of the reaction solution rose to 12.5 immediately after the addition of sodium silicate and sodium aluminate, and thereafter hardly changed. After the addition was completed, the reaction solution was cooled to room temperature and washed with an ultrafiltration membrane to prepare a dispersion liquid (F) of SiO ₂ .Al ₂ O ₃ porous material precursor particles having a solid content concentration of 20% by weight.

Next, 500 g of the dispersion liquid (F) of the porous material precursor particles was sampled, 1,700 g of pure water was added and the mixture was heated to 98 ° C., and while maintaining this temperature, an aqueous sodium silicate solution was added. Silica solution obtained by dealkalization with cation exchange resin (SiO ₂ concentration 3.5% by weight) 3,000
g was added to form a silica protective film on the surface of the porous material precursor particles. The obtained dispersion liquid of porous material precursor particles was washed with an ultrafiltration membrane to adjust the solid content concentration to 13% by weight, and 1,125 g of pure water was added to 500 g of the dispersion material of porous material precursor particles. In addition, concentrated hydrochloric acid (35.5%) was added dropwise to adjust the pH to 1.0, and after dealumination treatment, aluminum salt dissolved in the ultrafiltration membrane was added while adding 10 L of hydrochloric acid aqueous solution of pH 3 and 5 L of pure water. Separation was performed to prepare a particle precursor dispersion liquid.

A mixture of 1500 g of the above particle precursor dispersion, 500 g of pure water, 1,750 g of ethanol and 626 g of 28% ammonia water was heated to 35 ° C., and then 104 g of ethyl silicate (28% by weight of SiO ₂ ) was added. Then, a silica outer shell layer was formed from the hydrolyzed polycondensate of ethyl silicate on the surface of the particle precursor to prepare particles having voids inside the outer shell layer. Then, after concentrating to a solid content concentration of 5% by weight with an evaporator, ammonia water with a concentration of 15% by weight was added to adjust the pH to 10, and heat treatment was carried out at 180 ° C for 2 hours in an autoclave, and the solvent was converted to ethanol using an ultrafiltration membrane. A dispersion liquid of low-refractive-index particles (LP) having a solid content concentration of 20% by substitution was prepared.

When the cross section of the obtained particles was observed by a transmission electron microscope (TEM), it was found that cavities were formed inside the outer shell layer. The average particle size is 96n
m, and the refractive index was 1.31. A mixed solvent of ethanol / butanol / diacetone alcohol / isopropanol (2: 1: 1: 5 weight mixing ratio) was added to the liquid (A) containing the above matrix-forming components, and then the low refractive index particles (LP) were dispersed. Liquid is added, and the matrix-forming component SiO
₂ concentration 1% by weight, solid content of low refractive index particles 20% by weight
A transparent coating film-forming coating solution (B) was prepared. c) Manufacture of panel glass with transparent conductive coating The above-mentioned coating solution for forming transparent conductive coating (C) under conditions of 150 rpm and 90 seconds by spinner method while maintaining the surface of panel glass for cathode ray tubes (17 ") at 45 ° C. -1) to (C-11) were applied and dried, and the conductive fine particle layer had a thickness of
In Examples 6 to 12 and Comparative Examples 4 to 6, coating was performed so as to have a thickness of 200 nm, and in Comparative Example 7, the conductive fine particle layer was coated with a thickness of 30 nm and dried.

Then, on the transparent conductive fine particle layer thus formed, in the same manner, 100 rpm by a spinner method.
The coating solution (B) for forming a transparent film was applied and dried under the conditions of m and 90 seconds, and baked at 180 ° C. for 30 minutes to obtain a substrate with a transparent conductive film. At this time, the thickness of the transparent coating is 250 n
It was m. Separately from this, when a transparent coating having a thickness of 250 nm was formed on the glass substrate and the refractive index of the transparent coating was measured, it was 1.40, and the refractive index of the transparent coating was 1.40. .

The surface resistance of these transparent conductive film-coated substrates was measured by a surface resistance meter (LORESTA manufactured by Mitsubishi Yuka Co., Ltd.), and haze was measured by a haze computer (3000A manufactured by Nippon Denshoku Co., Ltd.).
It was measured at. Transmittance is spectrophotometer (JASCO Corporation: U
-Vest 560). The reflectance is measured using a reflectometer (MCPD-2000 manufactured by Otsuka Electronics Co., Ltd.), and the wavelength is 400 to 7
The reflectance at the wavelength with the lowest reflectance in the range of 00 nm is shown as the bottom reflectance, and the average reflectance in the range of wavelength 400 to 700 nm is shown as the luminous reflectance.

As reliability evaluations, salt water resistance and oxidation resistance tests were carried out by the following methods. [Salt Water Resistance] The transparent conductive film-coated substrate pieces obtained in the above Examples and Comparative Examples were immersed in a saline solution having a concentration of 5% by weight so as to be partially immersed in the saline solution for 24 hours and 48 hours. After leaving it for a period of time, it was taken out and the change in color tone with respect to the non-immersed part was observed.

[Oxidation resistance] The transparent conductive film-coated substrate pieces obtained in the above Examples and Comparative Examples were partially immersed in a hydrogen peroxide aqueous solution having a concentration of 2% by weight. After immersing in, and leaving it for 24 hours, it was taken out, and the change in color tone with respect to the non-immersed part was observed. [Display performance] A display device was assembled using the panel glass having the transparent conductive film obtained above, and the display performance was such that the degree of reflection (reflection) of the image and the fluorescent lamp at a distance of 5 m from the image surface and The degree of coloring was observed and evaluated according to the following criteria.

⊚: No reflection (reflection) and clear image ○: Weak reflection (reflection), sharp image Δ: Strong reflection (reflection), part of image Unclear x: Reflection (reflection) is clearer than the image

[0105]

[Table 2]

[Brief description of drawings]

FIG. 1 shows a schematic cross-sectional view of conductive metal oxide particles according to the present invention.

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) B32B 9/00 B32B 9/00 A H01B 1/08 H01B 1/08 1/20 1/20 Z 5/14 5/14 A (72) Inventor Toshiro Komatsu 13-2 Kitaminato-cho, Wakamatsu-ku, Kitakyushu City, Fukuoka Prefecture F-term in Wakamatsu Plant, Catalysis Chemicals Co., Ltd. (reference) 4D075 CA13 CA22 CB06 DA04 DA06 DA23 DB13 DB14 DB31 DC18 DC24 EA12 EB01 EB56 EB57 EC10 EC30 EC53 EC54 4F100 AA17B AA20 AA33B AT00A BA03 BA07 BA10A BA10C DE01B EH46 GB41 JD08 JG01B JG03 JN01B JN01C JN18C JN30 YY00B 5G301 DA02 DA01 DA02 DA02 DA03 DA02 DA02 DA02 DA23 DA02 DA02 DA23

Claims (9)

[Claims] 1. A conductive metal oxide particle comprising a conductive metal oxide, wherein Au, Ag, Pd, Pt, Rh, Ru, Cu, Fe, Ni, C are contained in the particles.
The conductivity improving component comprising a metal of one or more elements selected from o, and the content of the conductivity improving component in the conductive metal oxide particles is 0.01 in terms of metal.
The conductive metal oxide particles are characterized by being in the range of ˜1.5 wt%. 2. The conductive metal oxide particles according to claim 1, wherein the conductive metal oxide is indium oxide doped with Sn, Zn, Zr or F. 3. A method for producing conductive metal oxide particles, which comprises the following steps (a) to (e): (a) Dispersion of precursor (hydroxide) particles of conductive metal oxide. A step of adding the conductivity improving component fine particles to the liquid and mixing
(B) Then, a step of performing hydrothermal treatment in the range of 100 to 250 ° C., (c) a step of drying the obtained particle dispersion,
(D) 400 to 650 the powder after drying in a non-oxidizing atmosphere
Step of heat-treating in the temperature range of ° C, (e) Step of pulverizing the heat-treated powder. 4. A coating liquid for forming a transparent conductive film, comprising the conductive metal oxide particles according to claim 1 or 2 and a polar solvent. 5. The dipole moment of the polar solvent is 1.6.
The coating liquid for forming a transparent conductive film according to claim 4, wherein the coating liquid is in a range of from 5.0 to 5.0. 6. The coating liquid for forming a transparent conductive film according to claim 4, which contains an acid or an alkali ion. 7. A substrate, a transparent conductive fine particle layer containing the conductive metal oxide particles according to claim 1 on the substrate, and a transparent conductive fine particle layer provided on the transparent conductive fine particle layer, A transparent conductive film-coated substrate comprising a transparent coating film having a refractive index lower than that of the transparent conductive fine particle layer. 8. The transparent coating has an average particle diameter of 5 to 300.
8. The substrate with a transparent conductive film according to claim 7, which contains low refractive index particles having a refractive index of 1.45 or less in the range of nm. 9. A front plate comprising the substrate with a transparent conductive film according to claim 7 or 8, wherein the transparent conductive film is formed on the outer surface of the front plate. Display device.