JPS63143705A - Transparent conducting coat liquid composition and base material having transparent conducting film - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a method for producing transparent substrates such as glass or plastic that has excellent scratch resistance and durability without impairing the transparency of the substrate and is free from glare. The present invention relates to a transparent conductive coating liquid composition that forms a conductive film at low temperatures, and a transparent substrate on which a transparent conductive film is formed using the composition.

[Prior Art] Glass or plastic has particularly good transparency and is a base material, so it is used as a material for display devices, such as cathode ray tubes (ORT).
- Widely used for liquid crystal display (LCD) substrates, show windows, etc.

However, glass or plastic itself is an insulator and tends to accumulate static electricity on its surface, making it difficult to view images due to the accumulation of dirt and dust. Furthermore, electrostatic displays such as LCDs sometimes malfunction due to static electricity. Methods for making glass or plastic conductive and preventing static electricity include: ■ Applying conductive paint containing conductive powder and binder resin dispersed in a solvent; ■ Applying organic tin such as tin chloride or tin alkoxide. Spraying method, ■ Gas phase method such as PVD method or CVD method (electronic conductivity), ■ Spraying method with surfactant, silicon alkoxide, etc. (ion conductivity)
There is.

However, electronically conductive materials have sufficient conductivity, but in ■, they have poor transparency, scratch resistance, solvent resistance (the binder resin is attacked by solvents and the coating surface turns white), and water resistance (the film peels off).
For ■ and ■, the transparency is good, but the acid resistance, alkali resistance, and water resistance (the film peels off in all three) are poor, and the material that forms the film itself has a high refractive index, and the film surface is The smooth 9th corner gives off a glare that makes the video even more interesting to look at.

Furthermore, if a passivation film is not used in conjunction with ■, the alkali ions in the glass will move into the film during firing, reducing the conductivity.If the firing temperature is below 500°C, the alkali resistance will decrease and the conductivity will decrease. Deteriorate. In addition, the foul odor, corrosiveness, and explosiveness of the gas (droplets) pose problems to the work environment.■
However, it has poor scratch resistance and is expensive, and requires large equipment if the base material has a curved surface or a large area. The conductivity of the ionic conductive material (■) changed depending on the environment such as temperature and humidity, and its scratch resistance, alkali resistance (the film melted), and water resistance (peeled off) were poor.

[Problems to be Solved by the Invention] The present invention attempts to solve the problems associated with the prior art as described above. In contrast, a non-glare conductive coating with excellent scratch resistance, acid resistance, alkali resistance, solvent resistance, and water resistance (hereinafter referred to as durability) without impairing the transparency of the base material is produced at low temperatures. The object of the present invention is to provide a transparent substrate having a transparent conductive coating composition formed by the method and a transparent conductive liquid obtained by coating and curing the same.

[Ninth way to solve the problem]

The present invention improves the transparency of transparent substrates such as glass by uniformly dispersing zirconium oxyacid, non-precipitating silica, and conductive tin oxide colloid in water, a growth inhibitor, and a diluent. A transparent conductive coating liquid composition that forms a non-glare conductive film with excellent scratch resistance and durability without damage at low temperatures, and a transparent substrate having a transparent conductive film obtained by applying and curing the same. be.

In the present invention, a mixture of zirconia obtained from zirconium oxyacid salt and silica obtained from non-precipitated silica is used as a matrix, and conductive tin oxide colloid is dispersed in the matrix, thereby creating a transparent and conductive material. This is a transparent conductive coating liquid composition that forms a film. The glare of a coating depends on the reflectance of the coating.

The reflectance of a coating depends on its refractive index and the shape of its surface, which in turn depends on the material that makes up the coating and the density of the coating. Therefore, in order to lower the reflectance, only a substance with a small refractive index should be used, or a substance with a large refractive index should be mixed with a substance with a small refractive index, or the density of the coating should be reduced. Next, regarding the shape of the coating surface, the higher the smoothness, the higher the reflectance, so it is better to reduce the smoothness.
If the smoothness decreases too much, the transparency of the film will also decrease at the same time. Therefore, in the present invention, zirconia (refractive index 2.2) and silica (refractive index t,
S) to lower the refractive index of the matrix itself,
Furthermore, the film is made porous to lower its apparent refractive index, and the surface of the film is made uneven to the extent that transparency is not reduced to eliminate glare. However, in general, when a coating becomes porous, its surface area increases compared to a smooth coating, and its durability deteriorates. Zirconia is a highly durable material, but zirconia coatings are generally obtained using zircon alkoxide. However, zircon alkoxide has a fast hydrolysis rate, and it is difficult to control the rate, so it is difficult to control the hydrolysis rate before applying it to a transparent substrate as a coating liquid.
It is easily influenced by humidity, and the properties of the coating are influenced by the humidity, making it difficult to continuously obtain a coating with constant properties.

Furthermore, since it is hydrolyzed by a small amount of water, the coating solution cannot be stored for a long period of time. Furthermore, zircon alkoxide is expensive, so it is expensive to use as a raw material for industrial products. The present invention solves the conventional problems by using zirconium salt el.

As the zirconium salt according to the present invention, an oxyacid salt is used, and zirconium oxychloride and zirconium oxynitrate are particularly preferred.

Even when a zirconium oxyacid salt is applied in the form of an aqueous solution to a base material such as glass, the aqueous solution is repelled and no film is formed. This is caused by the low film-forming properties of the zirconium oxyacid salt and the high surface tension of the aqueous solution with respect to the substrate, but in order to further improve the film-forming property, non-precipitating silica was added. In order to lower the surface tension, it is necessary to mix an organic solvent with a low surface tension, or to remove part of the water from the system after mixing. However, with ordinary organic solvents, when the amount of water is reduced, the zirconium oxyacid salt and the non-precipitated silica become unstable, and may promote silica polymerization which decomposes and causes gelation. In the present invention, we investigated organic solvents that can act as growth inhibitors and prevent the decomposition and gelation of zirconium oxy-acid salts and non-precipitated silica from among various organic solvents. The above problems can be solved by mixing a specific organic solvent with a mixed aqueous solution of oxyacid, non-precipitating silica, and conductive tin oxide colloid, or by dehydrating part of the water from the system after mixing. I found a headline.

The coating liquid composition prepared in this way is stable even when the water content is low because the zirconium oxyacid salt and non-precipitating silica do not gel or polymerize because the organic solvent acts as a growth inhibitor. At the same time, it is possible to improve film-forming properties and reduce the surface tension of the coating composition.

Furthermore, when diluted with a diluent and applied to a substrate, even if the diluent, water, and some of the growth inhibitor evaporate, the remaining growth inhibitor decomposes and decomposes the zirconium oxyacid and non-precipitating silica. When gelation and polymerization are suppressed and the remaining growth inhibitor gradually evaporates, polymerization of the zirconium oxyacid salt and non-precipitable silica occurs and a ruptured membrane is formed. The reason why the film-forming property is improved by non-precipitating silica is probably that when the growth inhibitor gradually evaporates, the water If 2S of non-precipitating silica promotes the polymerization of zirconium with the oxyacid salt. I think so.

The conductive tin oxide colloid according to the present invention is a colloid in which tin oxide, tin oxide doped with a different element, or both are dispersed in an organic solvent. The particle size of the 2° colloidal particles, which are conductive tin oxide colloids obtained by the previously filed invention of “Tin Oxide Sol and Method for Producing Tin Oxide Sol” (Japanese Patent Application No. 75283/1983), is the average particle size. It is preferable that α is in the range of 01 to α1 μm. If it is less than 101 μm, the film cannot be made porous, and if it exceeds 111 μm, the haze value (hereinafter referred to as haze) of the resulting film becomes high, impairing the transparency of the substrate. However, even if the average particle size is 11μm or less, α1μm
If a large number of particles exceeding 1 μm are included, the haze of the film will increase and the transparency of the substrate will be reduced. Therefore, it is preferable to use a colloid in which a factor of 60 or more of the total particles is occupied by particles with a particle size of α1 μm or less. good.

The non-precipitable silica according to the present invention is obtained by exchanging alkali and hydrogen in an aqueous alkali silicate solution by a method such as an ion exchange method or a dialysis method, and 2.
Owtl (SiO1 equivalent) aqueous solution 250,0OO
G. Centrifugal sedimentation for 1 hour, just in case, the precipitate is all SiO in the aqueous solution! 30 parts by weight, preferably 10 parts by weight or less. Preferably, non-sedimenting silica obtained by the invention of "Non-sedimenting silica composition for coating and method for producing the same" (Japanese Patent Application No. 187835/1983) previously filed by the present applicant is used. The non-sedimented silica obtained in this manner is inherently unstable and tends to form colloidal particles or gel, but is stabilized by the growth inhibitor in the coating composition. Furthermore, this non-precipitating silica does not gel when mixed with zirconium oxyacid salts, nor does it gel zirconium oxyacid salts.

The growth inhibitor according to the present invention is one that does not cause gelation of zirconium oxysalt and non-precipitating silica, or one that does not promote polymerization, and is preferably N-methyl-2-pyrrolidone, N,N dimethylformamide, Morpholine, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol, etc., and their derivatives can be used singly or in combination of two or more.

The diluent according to the present invention may be any diluent that easily gels the zirconium oxyacid salt and the non-precipitating silica, such as methanol, ethanol, n-7'' lovanol, 1
-7' lovanol, n-butanol, 1-butanol,
Alcohols such as t-butanol, acetic acid methyl ester,
One or a combination of two or more of acid esters such as acetic acid ethyl ester, ethers such as diethyl ether, and acetone can be used.

Zr01・SiO!・Conductive tin oxide colloid ・Moisture ・
The composition ratio of the growth inhibitor/diluent is as follows: First, the growth inhibitor is a mob ratio to the total of ZrO2 and SiOfi, and is 1≦(growth inhibitor)/(zro i sio,) ≦2.
5 is good. Preferably the number is 2 or more.

If it is less than 1, the pot life (usable period) of the coating solution will be shortened, and long-term storage will not be possible. If it exceeds 25, when the coating liquid composition is applied and cured, the curing becomes uneven and the durability of the coating deteriorates. Second, water is Zr0
1, CL1≦J O/Z r
O! After satisfying the condition of ≦40≦40, s o
Wt1 or less is good. (If the weight ratio is less than 11, gelation of the zirconium oxyacid salt will occur, and if the weight ratio exceeds 40 or 5Qwt96 of the total weight, the growth inhibitor will be ineffective and the coating composition will be repelled on the transparent substrate.) Third, the total weight of ZrO2, 5102, and conductive tin oxide colloid is 11 to 20% of the total weight.
Wtl is preferable, and α
1 to 10 wt% is good.

This is because if it exceeds 2 o wtl, the stability of the coating solution will be poor and it will easily gel.

Fourth, the ratio of conductive tin oxide colloid, zirconium oxyacid salt, and non-precipitating silica is preferably 1≦(conductive tin oxide colloid)/(ZrO*+5iO1)≦5 (weight ratio). If there are no grooves, the conductivity of the coating will deteriorate,
Further, the film does not become porous, and when the number exceeds 5, the adhesion of the film decreases. Fifth, the ratio of non-precipitating silica and zirconium oxyaltate is α05≦SiOH/Zr01≦
1 (weight ratio) is good. This is because if it is less than 105, the adhesion of the film will be poor, and if it exceeds 1, the durability of the film will be poor.

The diluent may be added so that the transparent conductive coating composition of the present invention has a viscosity suited to the coating method or a desired film thickness.

The method for spreading the transparent conductive coating composition of the present invention is not particularly limited, but is preferably carried out by dispersing zirconium oxyacid, non-precipitating silica, and conductive tin oxide colloid in water and a growth inhibitor in advance. A portion of the water may be dehydrated from the mixed solution, or a diluent may be added without dehydration, and a distillation method or an ultrafiltration method can be used to dehydrate the water.

Transparent sM1 according to the present invention. The coating liquid composition is applied to a substrate by a conventionally known coating method such as a spinner method, a barcode method, a dip method, a spray method, a roll coating method, a printing method, etc., and then dried. For applications that require coatings with even higher durability and mechanical strength, f'1300°C can be used.
The above-mentioned firing may be performed at a temperature below the glass transition point of the base material.

The film obtained in this way has a total light transmittance (TI) of 9
Since the haze (H) is 0 or more and the haze (H) is 5 or less, the transparency of the transparent substrate is not impaired, and the surface resistance is 10 6 to 10 9 Ω/α 2 , which has an excellent antistatic effect and prevents glare. In addition, it is not attacked by acids and alkalis, and has excellent adhesion with water and salt water, with no change in the film.

Suitable transparent substrates include processed glass products such as glass plates and CRTs, sheets of polyethylene terephthalate, polycarbonate, and poly(meth)acrylate, and processed products thereof. In addition, when coating on a colored base material, a film can be formed without changing the color tone of the base material.

The conductive glass or plastic obtained using the conductive coating liquid composition of the present invention can be applied to antistatic display panels, copy glass, instrument display panels, transparent digitizers, telewriting terminals, etc. .

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

[Example] Example 1 318t of potassium stannate and 5a4f of tartarite were mixed with 686t of water.
? Prepare the raw material solution by dissolving the tiger. Add the above raw material solution together with nitric acid over 12 hours to too much water heated to 50°C and stirred, and hydrolyze while maintaining the system at paas to obtain a sol solution. Colloidal particles ftF are separated from this sol solution, washed to remove by-product salts, and the pore size particles are dried, calcined in air at 350°C for 3 hours, and then heated in air for 6 hours.
A fine powder was obtained by firing at 50° C. for 2 hours. Obtained powder 4
00f in potassium hydroxide aqueous solution 1600 t (KO1
The conductive tin oxide colloid was obtained by stirring the mixture in a sand mill for 3 hours while maintaining the mixture at 30°C. Next, this conductive tin oxide colloid was treated with an ion exchange resin to obtain a dealkalized conductive tin oxide colloid (conductive sol liquid). This dealkalized, electroconductive tin oxide colloid does not contain precipitates,
The solid content concentration was 20 wt4, and the average particle size of the colloid particles was CL07 μm. The amount of particles of 11 μm or less was 87% of the total particles. S10! as 5wt4 sodium silicate (51op/1321.
Q=3 mol/mol) 2000 f was passed through a hydrogen type ion exchange resin column at a space velocity of 8v=5 while being maintained at 15°C (non-precipitating silica liquid). 50t of this non-precipitating silica liquid and 50f of the conductive sol liquid
Then, N-methyl-2-pyrrolidone was added to 20f and Zr01
10 tons of 25 wt% zirconium oxychloride aqueous solution and MeOH/Bud)! (weight ratio 1/1) 1
Add 70t and mix thoroughly to obtain a transparent conductive coating composition.

Example 2 The non-precipitating silica liquid obtained in Example 1 was mixed with 502 f! and the conductive sol liquid was mixed with 200 f! Ic% N-methyl-2-pyrrolidone 10SF and 25wt% zirconium oxychloride aqueous solution in terms of ZrO2 with 4of and MeoH/1iXt
1400 f of oa (weight ratio 1/1) was added and sufficiently dispersed to obtain a transparent conductive coating liquid composition.

Example 3 N-methyl-2-pyrrolidone 10f and MeOH/BuO
H (weight ratio 1/1) 380? A transparent conductive coating liquid composition was obtained under the same conditions as in Example 1 except that .

Example 4 5Of of non-sedimentable silica liquid obtained in Example 1, 220t of conductive sol liquid, 11 of N-methyl-b-pyrrolidone
In terms of 0f and Zr01, 25 wt% zirconium oxychloride aqueous solution is 1002 and MaOH/ ]! :2O
Add H345F (weight ratio 1/1) and sufficiently disperse it to obtain a transparent conductive coating composition.

Example 5 The non-sedimenting silica solution obtained in Example 1 was uniformly mixed at 5°r, the conductive sol solution at 10of, 150t of N, Nil dimethylformamide, and 3ot of a 25wt4 zirconium oxynitrate aqueous solution in terms of ZrO2. After that, heat the water to 80°C while reducing the pressure using a rotary evaporator.
35 was dispensed. This liquid was cooled and further added with MsOH/
405 f of BuOH (weight ratio 1/1) was added and sufficiently dispersed to obtain a transparent conductive coating liquid composition.

Example 6 A transparent conductive coating liquid composition was produced under the same conditions as Example 1 except that 20 tons of ethylene glycol monomethyl ether was used.

Actual Stream 1317 A transparent conductive coating liquid composition was obtained under the same conditions as in Example 1 except that morpholine 2Qf was used.

Comparison row 1 The non-precipitating silica liquid obtained in Example 1 was used as 2001, the conductive sol liquid was used as 125f, and N-methyl-2-pyrrolidone 5
0? After uniformly mixing 10 f of a 25 wt% zirconium oxychloride aqueous solution in terms of ZrO, the mixture was heated to 80°C under reduced pressure using a rotary evaporator, and water was heated to 12
A 10 f drop volume was used. This liquid was cooled and further MeOH/
BuOH (weight ratio 1/1) 1075? We are good at creating transparent conductive coating liquid compositions by adding and sufficiently dispersing.

Comparative Example 2 The non-precipitating silica liquid obtained in Example 1 was added to 1002, the conductive sol liquid was added to 25f, and N-methyl-2-pyrrolidone was added to 40.
In terms of f and Zr01, 25wt* 20? and MeOB/BuOll
(weight ratio 1/1) 115f was added and sufficiently dispersed to obtain a transparent conductive coating liquid composition.

Comparative Example 3 Non-precipitating silica obtained in Example 1 was mixed with 1002, conductive sol liquid was mixed with 35of, N-methyl-2-pyrrolidone was mixed with 40% of N-methyl-2-pyrrolidone.
After homogeneously mixing 9 and 25wt1 zirconium oxynitrate aqueous solution 20F in terms of ZrO2, rotary evaporation
The mixture was heated to 80° C. under reduced pressure in a tank, and 2,502 ml of water was distilled out. This liquid was cooled and further MeOll/Bu
OH (weight ratio 1/1) 1340F is added and sufficiently dispersed to create a transparent conductive coating liquid composition.

Comparative Example 4 5002 of the non-sedimentable silica solution obtained in Example AJ1 and 500f of the conductive sol solution were mixed with 6f of N-methyl-2-pyrrolidone and 100f of a 25wt% zirconium oxynitrate aqueous solution in terms of Zr01. After mixing, the mixture was heated to 80 DEG C. under reduced pressure using a rotary evaporator to distill out 9,000 liters of water and gelatinize nine portions.

Comparative Example 5 10 of the non-sedimentable silica solution obtained in Example 1, 1002 of the conductive sol solution, 2 of N-methyl-2-pyrrolidone
51 and Zr0g, 5wt1 zirconium oxychloride aqueous solution is converted to 1001 and MeO)I/BuOH(
75f (weight ratio 1/1) was added and sufficiently dispersed to obtain a transparent conductive coating liquid composition.

Table 1 shows the liquid compositions and composition ratios of Examples and Comparative Examples.

The coating liquid compositions obtained in Examples 1 to 5 and Comparative Examples 1 to 55 were applied to a glass plate, and the transparent conductive coating liquid compositions obtained in Examples 6 and 7 were applied to an acrylic plate using a spinner. r
, p, m. The glass plate was dried at 110°C for 10 minutes and then fired at 300°C for 30 minutes, and the acrylic plate was dried at 110°C.
Dry for 30 minutes to obtain a film.

In addition, 20 times of the transparent conductive coating liquid composition obtained in Example GAU1 was spray-coated on a 14-inch cathode ray tube panel maintained at 60°C by supplying air at a pressure of 0 kg/1WO'' at 110°C for 10 minutes. Dry, 45
A film was obtained by firing at 0°C for 30 minutes. This will be referred to as Example 1'.

The obtained film was evaluated as follows.

The results are shown in Tables 2 and 3.

■Transparency: Total light transmittance (Tt) and haze (H) were measured using a haze computer (manufactured by Suga Test Instruments).

■ Glossiness: Glossiness (G) was evaluated at a measurement angle of 60° according to the glossiness measurement method of J-K 8K 7105-81.

■Adhesion: Attach a portion of commercially available 12-width cellophane tape to the film, hold the rest at right angles to the film, peel it off instantly, and visually inspect the presence or absence of the film on the glass.

■Hardness: Measured using the J-Tech 5DO202-71 pencil hardness test.

0 Surface resistance: Measured with an electrode cell (manufactured by YHP).

■Durability: 4 below! After soaking in liquid of type g1, the adhesion (■
The glossiness and surface resistance (same as ■ and ■) before and after the test were compared.

1) In 15vt% ammonia water at room temperature 120 hours.

2) 10 wt(j Na06 aqueous solution at room temperature
20 hours.

3) Submerge in boiling water for 30 minutes.

4) At room temperature in 50 wt% O acetic acid aqueous solution. 120 hours.

[Effects of the Invention] By adopting the above configuration, the present invention provides a conductive coating that has excellent durability, mechanical strength, and adhesion to transparent substrates such as glass without impairing the transparency of the substrate. can be formed at low temperatures. Further, the pot life (usable period) of the coating liquid composition of the present invention is 3 months or more at room temperature in a dark place.

In addition, when surface smoothness is required for a base material having a transparent conductive coating, or when it is desired to reduce the surface friction coefficient, polyester, acrylic, silicone, polypropylene, polyethylene, volistine, evoir, etc. may be applied to the coating according to the present invention. A transparent protective film made of resin or inorganic material such as silica can be provided.

Claims (1)

[Scope of Claims] (1) A transparent product characterized by uniformly dispersing zirconium oxyacid, non-precipitating silica, and conductive tin oxide colloid in a dispersion medium consisting of water, a growth inhibitor, and a diluent. Conductive coating liquid composition. (2) As a growth inhibitor, one or a combination of two or more of N-methyl-2-pyrrolidone, N,N dimethylformamide, morpholine, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol, and their derivatives. The transparent conductive coating liquid composition according to claim 1, which is used in the present invention. (3) A patent characterized by the use of a conductive tin oxide colloid obtained by heat-treating conductive tin oxide powder and/or conductive tin oxide powder doped with a different element in an acid aqueous solution or an alkaline aqueous solution. A transparent conductive coating liquid composition according to claim 1 or 2. (4) Convert zirconium oxyacid to ZrO_2, convert non-precipitated silica to SiO_2, and set the composition ratio of conductive tin oxide colloid, moisture, growth inhibitor, and diluent to 1≦(growth inhibitor )/(ZrO_2+SiO_2)≦2
5 (mol ratio) 0.1≦H_2O/ZrO_2≦40 (weight ratio) H_2O/(total weight of coating liquid composition)≦0.5 (weight ratio) 0.001≦(ZrO_2+SiO_2+conductive tin oxide colloid)/ (Total weight of coating liquid composition)≦0.2 (weight ratio) 1≦(conductive tin oxide colloid)/(ZrO_2+SiO
_2)≦5 (weight ratio) 0.05≦SiO_2/ZrO_2≦1 (weight ratio) The transparent conductive coating according to claim 1, 2, or 3, characterized in that liquid composition. (5) A coating solution in which zirconium oxyacid, non-precipitating silica, and conductive tin oxide colloid are uniformly dispersed in a dispersion medium consisting of water, a growth inhibitor, and a diluent is applied to the substrate and then cured. A base material with a transparent conductive coating.