JPH10147886A - Conductive film forming coating solution, conductive film and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coating soln. for forming a conductive film excellent in dispersion stability, appearance and conductivity by preparing a coating soln. consisting of the metallic fine particles with the average primary particle diameter specified and a water-soluble resin as a dispersion stabilizer. SOLUTION: A coating soln. contg. the metallic fine particles (Ag or Ru) having 10-100nm average primary particle diameter and a water-soluble resin >=1 kind among gelatin, PVA, polyacrylic acid, polyvinyl pyrrolidone and polyethylene glycol) as a dispersion stabilizer is prepared. At this time, 0.01-5wt.% metallic fine particle is dispersed in methanol, etc., and used, the mol.wt. of the water-soluble resin is controlled to 500-1,000,000, and 0.5-100wt.% resin is incorporated in the metallic fine particle. This coating soln. is applied on the surface of the glass substrate for a cathode-ray tube panel, etc., and a conductive film capable of shielding an electromagnetic wave and preventing reflection is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a low-resistance film (conductive film) having an electromagnetic wave shielding function and a low-reflection conductive film having an antireflection property, for example, by applying the film to a glass substrate surface such as a cathode ray tube panel. The present invention relates to a coating solution, a conductive film, a low-reflection conductive film, and a method for manufacturing the same.

[0002]

2. Description of the Related Art CRTs operate at a high voltage.
At startup or termination, static electricity is induced on the surface of the cathode ray tube. Dust adheres to the surface due to the static electricity, causing a decrease in the contrast of a displayed image and often causing discomfort due to a light electric shock when directly touched with a finger.

Heretofore, in order to prevent the above-mentioned phenomenon, attempts have been made to provide an antistatic film on the surface of a CRT panel.
A method has been adopted in which a conductive oxide layer such as tin oxide and indium oxide is provided on a panel surface by heating to about 0 ° C. and using a CVD method (JP-A-63-76247).

[0004] However, in this method, in addition to the equipment cost, there is a problem that the phosphor in the cathode-ray tube is dropped off or the dimensional accuracy is reduced due to heating the surface of the cathode-ray tube to a high temperature. In addition, tin oxide is generally used as a material for the conductive layer, but in this case, there is a disadvantage that it is difficult to obtain a high-performance film by low-temperature treatment.

In recent years, electromagnetic interference caused by electromagnetic noise to electronic equipment has become a social problem, and standards have been created and regulated to prevent it. Regarding electromagnetic noise, regarding the human body, there is a risk of skin cancer due to electrostatic charge on the CRT, the effect on the fetus by the low frequency electric field (ELF),
In addition, harm caused by X-rays, ultraviolet rays and the like is regarded as a problem in each country. Such a problem is solved by interposing a conductive coating on the surface of the cathode ray tube, causing electromagnetic waves to hit the conductive coating, inducing eddy currents in the coating, and reflecting the electromagnetic waves by this action. Can.

However, in order to exhibit such performance, the conductive film needs to have good conductivity to withstand high electric field strength, but it is more difficult to obtain such a good conductive film. there were.

On the other hand, with respect to a method of manufacturing a low-resistance film, for example, it has been proposed to form a low-resistance film by applying a mixed solution of a metal salt and a reducing agent to a substrate (JP-A-6-310).
However, in this method, since the stability of the metal salt solution is poor, it is necessary to apply the mixed solution to the substrate immediately after mixing the solution and the reducing agent, and the solution itself has poor film-forming properties. Therefore, there is a disadvantage that the appearance of the obtained film is poor.

Further, in order to form a low-resistance film, a liquid containing a metal salt and conductive oxide fine particles, or a liquid containing a metal salt and fine particles whose surface is coated with a metal has been proposed ( Japanese Unexamined Patent Publication (Kokai) No. 7-258860) discloses that the above conductive oxide fine particles are inferior in conductivity to the case of a single metal, while
The fine particles coated on the surface with metal also had a contact resistance at the interface between the metal and the non-metal fine particles, resulting in insufficient conductivity of the film.

Further, for the same purpose as above, metal oxide and P
It has been proposed to apply a liquid containing one or more metal fine particles of d, Sn, Pt, Ag and Au to a substrate (JP-A-63-160140). Was 0.01 μm or less, the activity of the fine particles was high, and the fine particles were aggregated with time, so that the liquid was inferior in long-term storage stability (long-term dispersion stability).

The low-resistance film formed as described above can be used not only in conventional optical devices but also in consumer devices, particularly TVs and cathode ray tubes (CRs) of computer terminals.
T) Although formed on a panel or the like, there are problems such as contrast of a displayed image and reflection of external light on the panel surface, and many studies have been made on prevention of such reflected light.

The conventional anti-reflection method includes, for example, attaching a SiO ₂ layer having fine irregularities on the surface of the cathode ray tube to have an anti-glare effect (Japanese Patent Laid-Open No. 61-1189).
31), a method of etching the surface with hydrofluoric acid to provide irregularities on the surface. However, these methods
It is called a non-glare treatment that scatters external light, and is not a method of providing a low-reflection layer in essence. Therefore, there is a limit to the reduction in reflectance, and in a cathode ray tube or the like, it also causes a reduction in resolution. .

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to overcome the above-mentioned disadvantages of the prior art, to provide excellent long-term dispersion stability in the state of a coating solution, and to form a film on a glass substrate such as a cathode ray tube face. In this case, a low-temperature heat treatment comprises a coating liquid capable of forming a transparent conductive film having no coloring and having excellent appearance and conductivity, and further capable of forming a low-reflection conductive film having an excellent antireflection effect. An object is to provide a conductive film, a low-reflection conductive film, and a manufacturing method thereof.

[0013]

According to the present invention, there is provided a coating liquid for forming a conductive film (hereinafter referred to as the present invention) comprising metal fine particles having an average primary particle diameter of more than 10 nm and not more than 100 nm and a water-soluble resin. The present invention provides a conductive film, a low-reflection conductive film, and a method for producing the conductive film.

According to the present invention, a conductive film which is excellent in dispersion stability in the state of a coating solution and which is transparent without coloration and excellent in appearance and conductivity by low-temperature heat treatment when forming a film on a glass substrate. Further, a low-reflection conductive film having an excellent antireflection effect can be formed.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The fine metal particles used in the present invention may be any fine metal particles as long as the fine metal particles have a predetermined particle diameter, but are preferably fine particles of Ag or Ru. These fine particles can be produced by various methods. In particular, it is preferable to produce a metal fine particle by mixing a compound capable of reducing the metal compound contained in the metal compound solution into the metal compound solution.

In the metal fine particle dispersion used in the present invention, the average primary particle diameter of the metal fine particles is more than 10 nm and 100 nm.
It is important that: If the average primary particle size of the metal fine particles is more than 100 nm, scattering of visible light increases in the formed film, and the transparency of the film is significantly reduced. If the average primary particle size of the metal fine particles is 10 nm or less, the uniform dispersibility and dispersion stability of the metal fine particles in the present coating solution are significantly impaired.

In the present invention, in order to maintain the dispersion stability of the metal fine particle dispersion for a long period of time, to suppress the aggregation of the fine particles during coating film formation, and to improve the conductivity chain of the formed film, the metal fine particle dispersion is used. Is added with a water-soluble resin.

The water-soluble resin preferably has an average molecular weight (average molecular weight determined by gel permeation chromatography) of 500 to 1,000,000. When the average molecular weight is less than 500, the steric hindrance effect of the water-soluble resin is reduced, so that the steric stability of the fine particles is poor, and coalescence of the fine particles progresses with time. If the average molecular weight is more than 1,000,000, the distance between the metal fine particles in the formed film is too large, and the film has a high resistance. The water-soluble resin is desirably at least one selected from the group consisting of gelatin, polyvinyl alcohol, polyacrylic acid, polyvinylpyrrolidone and polyethylene glycol.

The amount of the water-soluble resin to be added is preferably in the range of 0.5 to 100% by weight based on the metal fine particles. When the addition amount is less than 0.5% by weight, the steric hindrance effect on the metal fine particles by the resin is reduced, the coalescence of the fine particles progresses with time, the average particle diameter of the particles exceeds 100 nm, and the visible light of the formed film is increased. Scattering, the transparency of the film is remarkably reduced, and sedimentation of metal fine particles also occurs. When the addition amount exceeds 100% by weight, the dispersion stability of the liquid is good, but the water-soluble resin remaining in the formed conductive film is large, and the contact between the metal fine particles is deteriorated, and the conductive property of the formed film is deteriorated. Lack of chaining property increases the resistance of the film.

When a metal fine particle dispersion is used, the surface tension, viscosity, etc. of the liquid must be controlled in order to adjust the appearance of the film to be formed. Therefore, it is preferable to dilute with an organic solvent having a lower dielectric constant than water, which is not preferable for the dispersion stability of the metal fine particles.

As such organic solvents, methanol,
Ethanol, n-propanol, isopropanol, n
-Butanol, isobutanol, sec-butanol,
monohydric alcohols such as tert-butanol, polyhydric alcohols such as ethylene glycol, ethyl cellosolve,
Ethers such as methyl cellosolve, butyl cellosolve and propylene glycol methyl ether; ketones such as 2,4-pentanedione and diacetone alcohol; esters such as ethyl lactate and methyl lactate; amides such as N-methylpyrrolidone; dimethyl sulfoxide And sulfur compounds such as sulfolane.

It is desirable to add a water-soluble resin in order to impart long-term dispersion stability of the metal fine particles in the coating solution diluted with such a solvent. When a solvent having a higher boiling point than water in the organic solvent is added to the coating solution, the solvent evaporates later than water when the film is dried after coating. Therefore, during the drying of the film, the mixed dielectric constant of the coating liquid decreases, the metal fine particles become unstable and aggregate, the fineness of the fine particles decreases, and the conductive chain property of the film deteriorates. It is desirable to add a water-soluble resin to stabilize the fine particles with steric hindrance in order to suppress the aggregation of the fine metal particles during the drying of the film.

The concentration of fine metal particles in the coating solution is 0.01
-5% by weight, particularly preferably 0.05-2% by weight. If the concentration of the metal fine particles is more than 5% by weight, the transparency of the formed film is remarkably reduced. If the concentration of the metal fine particles is less than 0.01% by weight, the resistance of the formed film is undesirably increased.

In order to change physical properties such as transmittance of a film formed in the present coating solution, Sn, Sb, In, Zn,
At least one metal compound selected from the group consisting of Ga, Ru, Al, Si, Ti and Zr, preferably a metal oxide sol may be added. The addition ratio is preferably 9/1 or less in terms of a weight ratio of the metal compound to Ag in terms of oxide. Although there is no particular limitation on the compound to be added, it is preferable to use Sn-doped In ₂ O ₃ or Sb-doped SnO ₂ because the transmittance can be controlled without increasing the resistance of the formed film.

It is preferable to use SiO ₂ , particularly SiO ₂ sol obtained by hydrolyzing ethyl silicate or the like as an additive, because the coating suitability of the present coating solution is improved. When TiO ₂ or ZrO ₂ is used as an additive,
This is preferable because the suitability for application of the present coating solution and the color tone of the formed film can be controlled. These additives may be added to the above-mentioned metal fine particle dispersion in the form of fine particles or hydrolyzates of alkoxides, or may be added as a liquid dispersed by a disperser such as an ultrasonic disperser or a sand mill. Further, in order to improve the wettability of the present coating solution to the substrate, various surfactants may be added to the present coating solution.

Since the present coating solution itself is used as a coating solution on a substrate, when a low-boiling solvent is added to the coating solution, a coating film can be obtained by drying at room temperature. When a medium to high boiling point solvent having a boiling point of 100 to 250 ° C. is used as a solvent for the liquid, heat treatment is performed because the solvent remains in the coating film even when the coating film is dried at room temperature. The upper limit of the heating temperature is determined by the softening point of glass, plastic, or the like used as a substrate. Considering this point, the heating temperature range is preferably 100 to 500 ° C.

Further, as a method for curing the film of the present invention, the coating film may be irradiated with ultraviolet rays (UV). Since the coating film composed of this coating solution contains Ag fine particles, an absorption peak exists around 330 nm caused by the 5s band and 5d band of Ag, and when UV is irradiated as a curing means, energy is efficiently consumed. Absorbed and excellent film hardening action is exhibited.

Further, in the present invention, a low refractive index film can be formed on the conductive film formed as described above by utilizing the interference effect of light. For example, if the substrate is glass (refractive index n =
In the case of 1.52), a low refractive index film is formed on the conductive film so that the ratio of the refractive index of the conductive film to the refractive index of the low refractive index film is about 1.23. The reflectance of the formed film can be reduced most. In order to reduce the reflectance of the film, it is preferable to reduce the reflectance particularly at 555 nm in the visible light region. However, in practice, it is preferable to determine the reflectance appropriately in consideration of the reflection appearance and the like.

The low-refractive-index film in the low-reflection conductive film having two layers is preferably formed by using a coating solution containing a silicon compound from the viewpoint of the hardness of the formed film. Further, from the viewpoint of the refractive index, the coating liquid for forming a low refractive index film may contain MgF ₂ sol.

As the silicon compound for forming the low refractive index film as described above, various compounds including Si alkoxide can be used. As a suitable material, for example, Si (OR) _y.
A liquid containing a Si alkoxide represented by R ′ _4-y (y is 3 or 4, R and R ′ is an alkyl group) or a partial hydrolyzate thereof is exemplified. For example, a monomer or polymer of silicon ethoxide, silicon methoxide, silicon isopropoxide, or silicon butoxide can be preferably used.

The Si alkoxide can be used by dissolving it in an alcohol, an ester, an ether, or the like. A hydrochloric acid, a nitric acid, a sulfuric acid, an acetic acid, a formic acid, a maleic acid,
It can also be used by adding hydrofluoric acid or an aqueous ammonia solution to hydrolyze the Si alkoxide. Further, it is preferable that the Si alkoxide is contained in an amount of 30% by weight or less based on the solvent. If the solid content of the Si alkoxide is too large, the storage stability of the liquid will deteriorate.

The Si alkoxide solution contains Zr and Zr as binders to improve the strength of the formed film.
Alkoxides such as Ti, Sn, and Al, and partial hydrolysates thereof are added, and one or more selected from ZrO ₂ , TiO, SnO _2, and Al ₂ O ₃ are added to MgF ₂ or SiO _2.
At the same time, they may be precipitated. Further, a surfactant may be added to the Si alkoxide solution in order to improve the wettability of the solution to the substrate. Examples of the surfactant to be added include sodium linear alkylbenzene sulfonate and alkyl ether sulfate.

The low-reflection conductive film of the present invention is obtained by applying and coating the present coating solution on a substrate, and then applying a coating solution for forming a low-refractive-index film containing at least a silicon compound thereon. It is obtained by forming a film.

The present coating solution can also be used for producing a low-reflection conductive film by the multilayer interference effect. As the configuration of the multilayer low refractive index film having antireflection performance, the wavelength of the light to be antireflective is λ, and the high refractive index layer−the low refractive index layer is formed from the base side to the optical thickness λ / 2−λ / 4, or two low-refractive-index films formed at λ / 4-λ / 4, and an optical thickness λ / 4-λ / 2-λ of a medium refractive index layer—a high refractive index layer—a low refractive index layer from the substrate side. / 4, and the optical thickness of the low refractive index layer, the medium refractive index layer, the high refractive index layer, and the low refractive index layer from the substrate side is λ / 2−λ.
A typical example is a four-layer low-refractive-index film formed at / 2-λ / 2-λ / 4.

The coating liquid of the present invention can be used for forming the medium to high refractive index layer of the above-mentioned multilayer constitution film, and the coating liquid for forming the low refractive index film is used for forming the low refractive index layer of the above-mentioned multilayer constitution film. it can.
Examples of the substrate on which the conductive film or the low-reflection conductive film of the present invention are formed include various types of glass such as a cathode ray tube panel, a glass plate for a copying machine, a panel for a computer, a glass for a clean room, a front plate of a display device such as a CRT or an LCD, and a plastic. Substrates and the like can be mentioned.

The coating method of the present coating liquid on a substrate includes:
Methods such as spin coating, dip coating and spray coating can be suitably employed. Further, the surface may be made uneven by using a spray coating method to impart an antiglare effect to the formed film, or a hard coat layer such as a silica coating may be provided thereon. Further, the conductive film of the present invention is formed by a spin coating method or a spray coating method, and S
A solution containing i-alkoxide may be spray-coated to form a silica coating non-glare coat layer having irregularities on the surface.

The amount of coating (film thickness) of the present coating solution and the coating solution for forming a low refractive index film on the substrate is not generally defined by the type of the substrate to be coated, the purpose of use of the substrate to be coated, and the like. The coating amount is generally about 5 to 5
The coating amount of the coating liquid for forming a low refractive index film is generally about 5 to 150 as a thickness of a cured film.
The range of nm is preferable. If the thickness of the formed conductive film is less than 5 nm, it is insufficient in terms of the conductivity of the film and low reflectivity when forming a two-layer film or a multilayer film. It is insufficient in terms of transmittance and low reflectivity when forming a two-layer film.

The low refractive index film to be formed has a thickness of 5n.
If the thickness is less than 150 m, the strength of the film and the low reflectivity during the formation of a two-layer film or a multilayer film are insufficient. Inadequate in point. Note that a low-reflection conductive film having a multilayer structure can be formed by interposing another film above and below the conductive film and the low-refractive-index film.

[0039]

Next, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples. In the following Examples and Comparative Examples, the average primary particle size of the fine particles in the obtained sol was measured by a transmission electron microscope. The evaluation method of the obtained film is as follows.

1) Conductivity evaluation: The surface resistance of the film surface was measured using a Loresta resistance meter (manufactured by Mitsubishi Yuka). 2) Scratch resistance: Eraser under 1 kg load (Lion 5
After the film surface was reciprocated 50 times (0-50), the degree of scratching on the surface was visually determined. The evaluation criteria were as follows: ：: no scratch at all, Δ: slightly scratched, x: partial film peeling. 3) Luminous reflectance: Luminous reflectance at 400 to 700 nm of the film was measured with a GAMMA spectral reflectance spectrum measuring instrument. 4) Luminous transmittance: Luminous transmittance at 380 to 780 nm was measured with a spectrophotometer U-3500 manufactured by Hitachi, Ltd.

Example 1 "Preparation of Ag fine particle dispersion" (1) 35 g of a 30 wt% aqueous solution of trisodium citrate was added to 20 g of a 30 wt% aqueous solution of iron sulfate, and 25 g of a 12 wt% aqueous solution of silver nitrate was added. Stirred for minutes. (2) After the liquid obtained in the above (1) was subjected to solid-liquid separation by centrifugation, 30 g of pure water was added to the precipitate and stirred. After irradiating the solution with ultrasonic waves for 10 minutes, 30 g of a 30% by weight aqueous solution of trisodium citrate was added.

(3) After repeating the above step (2) four times, the mixture was separated into solid and liquid by centrifugation, 50 g of pure water was added, and ultrasonic irradiation was further performed for 20 minutes. (4) After adding the cation exchange resin to the liquid obtained in the above (3) and stirring for 15 minutes, the cation exchange resin is separated by filtration, and further the anion exchange resin is added and stirred for 15 minutes. Then, the anion exchange resin was separated by filtration to obtain a dispersion liquid of Ag fine particles. The average primary particle size of Ag fine particles in this dispersion is 27 n.
m, and its solid content concentration was 5% by weight (A
liquid).

(5) The solution A has an average molecular weight of 200,0
Then, an aqueous solution of gelatin was added so that the solid content of gelatin was 30% by weight based on the solid content of Ag fine particles.
It was adjusted to 35% by weight (A1 solution).

"Preparation of Silicon Compound-Containing Liquid" (6) Ethyl silicate (50 g) was dissolved in ethanol (200 g), a mixed solution of concentrated nitric acid (1.5 g) and pure water (33 g) was added dropwise with stirring, and the mixture was stirred at room temperature for 2 hours. Thus, a solution having a SiO ₂ concentration of 4.9% by weight was obtained (Solution B). The solution B was diluted with a mixed solvent of propylene glycol monomethyl ether / isopropanol / diacetone alcohol = 50: 40: 10 (weight ratio) so that the SiO ₂ solid content was 0.70% by weight (solution B1).

"Coating and Curing" (7) 20 g of the A1 solution was heated to a surface temperature of 40 ° C.
The spin-coating method is applied to the surface of the inch type cathode ray tube panel at a coating amount of 100 rpm and 6 rpm to give a film thickness of 40 nm upon curing.
After coating under the condition of 0 second, 20 g of the B1 solution was cured to a thickness of 60 nm under the same spin coating conditions as when the A1 solution was applied.
Then, the coating was heated at 160 ° C. for 30 minutes to obtain a low-reflection conductive film.

Example 2 An aqueous solution of polyvinyl alcohol having an average molecular weight of 22,000 was added to the solution A so that the solid content of polyvinyl alcohol was 10% by weight based on the solid content of Ag fine particles, and then ethanol / ethylene glycol monomethyl was added. Ether / dimethylformamide / dimethylsulfoxide = 6
A 5/30/3/2 (weight ratio) mixed solvent (hereinafter, this mixed solvent is referred to as mixed solvent M) was adjusted so that the Ag solid content was 0.35% by weight (A2 liquid).

20 g of the A2 solution was applied onto the surface of a 14-inch CRT panel heated to a surface temperature of 40 ° C. by a spin coating method at a coating amount of 100 rpm to give a film thickness of 40 nm upon curing.
m, for 60 seconds, and then apply 20 g of B1 solution to A2
Film thickness of 6 when cured under the same spin coating conditions as for liquid application
After coating with a coating amount of 0 nm, the coating was heated at 160 ° C. for 30 minutes to obtain a low-reflection conductive film.

Example 3 An aqueous solution of polyacrylic acid having an average molecular weight of 2,000 was added to the solution A so that the solid content of polyacrylic acid was 1% by weight with respect to the solid content of Ag fine particles. M to adjust the Ag solid content to 0.35% by weight (A
3 liquids).

20 g of the A3 solution was applied to the surface of a 14-inch cathode ray tube panel heated to a surface temperature of 40 ° C. by spin coating at a coating amount of 100 rpm to give a film thickness of 40 nm upon curing.
m, for 60 seconds, and then apply 20 g of B1 solution to A3
Film thickness of 6 when cured under the same spin coating conditions as for liquid application
After coating with a coating amount of 0 nm, the coating was heated at 160 ° C. for 30 minutes to obtain a low-reflection conductive film.

Example 4 An aqueous solution of polyvinylpyrrolidone having an average molecular weight of 630,000 was added to the solution A so that the solid content of polyvinylpyrrolidone was 15% by weight with respect to the solid content of Ag fine particles. Ethyl ether / dimethylformamide / dimethylsulfoxide = 6
A 5/30/3/2 (weight ratio) mixed solvent (hereinafter, this mixed solvent is referred to as mixed solvent N) was adjusted so that the Ag solid content was 0.35% by weight (A4 liquid).

20 g of the A4 solution was applied onto the surface of a 14-inch CRT panel heated to a surface temperature of 40 ° C. by spin coating at a coating amount of 100 rpm to give a film thickness of 40 nm upon curing.
m, for 60 seconds, then apply 20 g of B1 solution to A4
Film thickness of 6 when cured under the same spin coating conditions as for liquid application
After coating with a coating amount of 0 nm, the coating was heated at 160 ° C. for 30 minutes to obtain a low-reflection conductive film.

Example 5 "Preparation of Ru Fine Particle Dispersion" (1) 1% in 200 g of 10% by weight aqueous ruthenium trichloride solution
100 g of a 5% by weight aqueous sodium borohydride solution was added to precipitate metal ruthenium. (2) The metal ruthenium obtained in the above (1) was sufficiently washed with water and dried at 100 ° C. for 24 hours to obtain a metal ruthenium powder. (3) 10 g of this metal ruthenium powder was suspended in 50 g of water and pulverized with a sand mill for 20 minutes to obtain a Ru fine particle dispersion. The average primary particle size of the Ru fine particles in this dispersion is 50 n.
m and its solids content was 8% by weight (Solution C).

To the solution C obtained in the above (3), an aqueous solution of polyethylene glycol having an average molecular weight of 20,000 was added to Ru.
After adding so that the polyethylene glycol solid content becomes 50% by weight with respect to the fine particle solid content, Ru is mixed with the mixed solvent N.
The solid content was adjusted to 0.35% by weight (C1
liquid).

20 g of the C1 solution was applied to the surface of a 14-inch CRT panel heated to a surface temperature of 40 ° C. by spin coating at a coating amount of 100 rpm to give a film thickness of 40 nm upon curing.
m, for 60 seconds, then apply 20 g of B1 solution to C1
Film thickness of 6 when cured under the same spin coating conditions as for liquid application
After coating with a coating amount of 0 nm, the coating was heated at 160 ° C. for 30 minutes to obtain a low-reflection conductive film.

Example 6 Indium oxide particles (hereinafter referred to as ITO) in which 5% by weight of Sn was substituted and solid-dissolved were pulverized and pulverized with a sand mill for 1 hour to obtain an ITO fine particle dispersion (solution D). In the solution A,
Ag aqueous solution of polyacrylic acid with average molecular weight of 5,000
2% by weight of polyacrylic acid solids based on solids of fine particles
After the addition, the solution D was added to Ag / ITO = 8/2.
(Weight ratio), and (Ag + I
TO) The solid content was adjusted to 0.35% by weight (D1 solution).

20 g of the D1 solution was applied onto the surface of a 14-inch CRT panel heated to a surface temperature of 40 ° C. by spin coating at a coating amount of 100 rpm to give a film thickness of 40 nm upon curing.
m, for 60 seconds, and then apply 20 g of B1 solution to D1
Film thickness of 6 when cured under the same spin coating conditions as for liquid application
After coating with a coating amount of 0 nm, the coating was heated at 160 ° C. for 30 minutes to obtain a low-reflection conductive film.

Example 7 An aqueous solution of polyvinylpyrrolidone having an average molecular weight of 210,000 was added to Solution A so that the solid content of polypinylpyrrolidone was 20% by weight based on the solid content of Ag fine particles. Ag / S20L)
The mixture was added so that SiO ₂ = 9/1 (weight ratio), and the mixed solvent N was adjusted so that the solid content of (Ag + SiO ₂ ) became 0.4% by weight (Solution E).

20 g of Solution E was applied to the surface of a 14-inch CRT panel heated to a surface temperature of 40 ° C. by spin coating at a coating amount of 100 rpm to give a film thickness of 40 nm upon curing.
After coating under the conditions of m and 60 seconds, 20 g of the B1 solution has a film thickness of 60 when cured under the same spin coating conditions as when applying the E solution.
After coating with a coating amount of nm, the coating was heated at 160 ° C. for 30 minutes to obtain a low-reflection conductive film.

Example 8 An aqueous solution of polyvinyl alcohol having an average molecular weight of 22,000 was added to the solution A so that the solid content of polyvinyl alcohol was 20% by weight based on the solid content of Ag fine particles. Commercially available, TC-310) was added so that Ag / TiO ₂ = 9/1 (weight ratio).
0.4% by weight of (Ag + TiO ₂ ) solid content in mixed solvent N
(F solution).

20 g of solution F is applied to the surface of a 14-inch type cathode ray tube panel heated to a surface temperature of 40 ° C. by spin coating at a coating amount of 100 rpm to give a film thickness of 40 nm upon curing.
After coating under the conditions of m and 60 seconds, 20 g of the B1 solution has a thickness of 60 when cured under the same spin coating conditions as when applying the F solution.
After coating with a coating amount of nm, the coating was heated at 160 ° C. for 30 minutes to obtain a low-reflection conductive film.

Comparative Example 1 The solution A was adjusted with the mixed solvent N so that the Ag solid content was 0.35% by weight (solution G). 20 g of solution G was applied to the surface of a 14-inch cathode ray tube panel heated to a surface temperature of 40 ° C. by a spin coating method under the conditions of 100 rpm for 60 seconds at an application amount of a film thickness of 40 nm upon curing, followed by B1
After applying 20 g of the solution under the same spin coating conditions as in the case of applying the G solution, with an application amount such that the film thickness upon curing becomes 60 nm,
C. for 30 minutes to form a film of Comparative Example 1.

Example 9 A low-reflection conductive film was obtained in the same manner as in Example 1 except that the A1 solution was allowed to stand at room temperature for 6 months and then applied to a 14-inch CRT panel.

Example 10 A low reflection conductive film was obtained in the same manner as in Example 6, except that the D1 solution was allowed to stand at room temperature for 6 months and then applied to a 14-inch CRT panel.

Comparative Examples 2-3 The above solution A was adjusted using ethanol and water so that ethanol was 80% by weight and Ag solid content was 0.35% by weight (solution H). 20 g of H solution was applied to the surface of a 14-inch CRT panel heated to a surface temperature of 40 ° C. by a spin coating method at an application amount of 100 rpm at a film thickness of 40 nm when cured.
After coating under the conditions of m and 60 seconds, 20 g of the B1 solution has a thickness of 60 when cured under the same spin coating conditions as when the H solution is applied.
After coating at a coating amount of nm, the film was heated at 160 ° C. for 30 minutes to form a film of Comparative Example 2.

After leaving the solution H at room temperature for one month,
The spin-coating method is applied to the surface of the inch type cathode ray tube panel at a coating amount of 100 rpm and 6 rpm to give a film thickness of 40 nm upon curing.
After applying under the condition of 0 second, 20 g of the B1 solution was applied under the same spin coating conditions as in the H solution application with an application amount such that the film thickness when cured became 60 nm, and then heated at 160 ° C. for 30 minutes to obtain a comparative example. Film No. 3 was formed.

[Evaluation Results] Examples 1 to 10 and Comparative Example 1
Tables 1 and 2 show the results of measuring the physical properties of each of the conductive films obtained in Nos. 1 to 3 by the above method. In the table, 2E2 is 2 × 10 ²
And the same applies to the others.

[0067]

[Table 1]

[0068]

[Table 2]

[0069]

According to the present invention, the coating solution is excellent in long-term dispersion stability, and when a film is formed on a glass substrate such as a cathode ray tube face, it is transparent without coloration due to low-temperature heat treatment, and its appearance, A conductive film having excellent conductivity and a low-reflection conductive film having an excellent antireflection effect can be formed.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoneda Rare 1150 Hazawa-cho, Kanagawa-ku, Yokohama, Kanagawa Prefecture Inside the Central Research Laboratory Asahi Glass Co., Ltd. Central Research Laboratory

Claims (9)

[Claims] 1. A coating solution for forming a conductive film, comprising fine metal particles having an average primary particle size of more than 10 nm and not more than 100 nm and a water-soluble resin as a dispersion stabilizer. 2. The coating solution for forming a conductive film according to claim 1, wherein the metal fine particles are fine particles of Ag or Ru. 3. The coating liquid for forming a conductive film according to claim 1, wherein the water-soluble resin is at least one selected from the group consisting of gelatin, polyvinyl alcohol, polyacrylic acid, polyvinylpyrrolidone and polyethylene glycol. 4. A water-soluble resin having a molecular weight of 500 to 1,000.
4. The coating liquid for forming a conductive film according to claim 1, wherein the coating liquid is 000. 5. The method according to claim 1, wherein the content of the water-soluble resin is 0.5 to 100% by weight based on the metal fine particles.
Coating liquid for forming a conductive film. 6. Further, Sn, Sb, In, Zn, Ga, R
The coating solution for forming a conductive film according to claim 1, further comprising a sol in which oxide particles of one or more metals selected from the group consisting of u, Al, Si, Ti, and Zr are dispersed. 7. A conductive film obtained by applying the coating liquid for forming a conductive film according to claim 1 on a glass substrate. 8. A low reflection conductive film, wherein a film having a lower refractive index than the conductive film is formed on the conductive film according to claim 7. 9. A coating solution for forming a conductive film according to any one of claims 1 to 6, which is applied on a substrate, and a coating solution for forming a low refractive index film containing at least a silicon compound is applied thereon. A method for producing a low-reflection conductive film, comprising: