JPS62267476A - Composition for forming transparent electrically conductive coated film - Google Patents

Abstract

PURPOSE:To prepare the title composition without generating a harmful org. fluorine compd. by mixing an org. tin compd. such as tin alkoxide, a compd. having an Sn-F coupling, and a solvent. CONSTITUTION:At least one kind of org. tin compd. among a stannous or stannic alkoxide, an org. stannate, and a tin beta-diketone complex, a stannous or stannic compd. having an Sn-F coupling, and a solvent are mixed, and the mixture is preferably refluxed and heated. Consequently, a composition for forming a transparent conductive coated film contg. 0.01-10wt%, based on Sn, is obtained. The composition provides a tin oxide coated film having excellent transparency and strength with with the addition of a tin fluoride compd. Besides, a corrosive fluorine compd. is not generated during baking, and the composition is advantageous in practical use.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a composition for forming a transparent conductive film on the surface of a substrate such as glass or ceramic.

Sn formed on an insulating substrate such as glass or ceramics,
Oxide films such as In, Zn, and Cd have high visible light transmittance and good conductivity, and are used in transparent electrodes for EL, liquid crystal display elements, electrochromic display elements, solar cells, etc., automobiles, It is used as an anti-fog resistance heating coating for window glass of aircraft, buildings, etc.

[Conventional technology]

As transparent conductive films, SnO, type and In, O, type are well known, and methods for forming these films include S.
A method of physically attaching nO□, In2O, etc. to the substrate surface under reduced pressure such as vapor deposition or sputtering, and a method of spraying a solution of a tin compound or indium compound onto a preheated substrate to cause thermal decomposition and oxidation. A method is known in which an oxide film is formed by raising the oxide film, and a method in which a solution containing a tin compound or an indium compound is applied onto a substrate and then baked to form an oxide film. Although transparent conductive films have been obtained by the methods described above,
In order to obtain a stable low-resistance transparent conductive film, antimony, fluorine, and In2O are used as resistance adjusters for SnO□ series.
.

In these systems, tin and fluorine are often added.

〔problem〕

In particular, organic fluorides, fluorinated organic acids, etc. can also be used as a method for adding fluorine in coating and baking methods, spray methods, and the like. However, in that case, the conductivity will not increase unless the heat treatment temperature is raised to around 600 to 700°C, which is not suitable when using a substrate with a low melting temperature. Further, during thermal decomposition, fluorine compound gas is generated which is toxic to the human body and highly corrosive, which poses many practical problems.

[Means to solve the problem]

Fluorine, which has a resistance adjustment function in the tin oxide film, is
It has been found that by adding a compound having an F bond to a tin alkoxide solution to form a uniform solution, it is possible to suppress the generation of large amounts of fluorine compounds that are sometimes toxic and corrosive to the human body during coating and baking.

[Structure of the invention]

According to the present invention, at least one of divalent or tetravalent tin alkoxide, organic acid tin, and tin β-diketone complex and S
It consists of a divalent or tetravalent tin fluoride compound having an n-F bond and a solvent, and has a fluorine content of 0.0% in F/Sn weight ratio.
01-10.0% of the transparent conductive film-forming composition is provided.

The composition of the present invention comprises a divalent or tetravalent tin alkoxide,
At least one type of tin oxide, tin β-diketone complex (hereinafter referred to as an organic tin compound), a divalent or tetravalent tin compound having an Sn-F bond, and a solvent are simply mixed, preferably under reflux. Obtained by heating.

In the composition of the present invention, the divalent or tetravalent tin alkoxide or organic acid tin, tin β-diketone complex is Sn (O
R)2 (R is an alkyl group, the same applies hereinafter), Sn(OR)
,, SnC1n (OR), n (n=1-3), S
nC1(Oll)(OR),, SnC12(Oll)
(OR); Sn-to-C-R)2. Sn(A-A
) z etc. or a mixture thereof.

In the composition of the present invention, the tetravalent tin compound having a Sn-F bond is SnF4. SnFy+(OR)+-n (
R is a lower alkyl group, the same applies hereinafter, n = 1 to 3), SnC
1fflF, (OR) (41-,)(16m (4
, 1≦n (4 and m+n<4), SnFz (
A-A)z (A-A is a substituted or unsubstituted β-diketone), SnF2 (OOCR)2. SnF R-(n=1
-3) etc.

n (4n) In the composition of the present invention, the solvent is an alcohol having 1 to 20 carbon atoms, an ester, a ketone, a β-carbon, an ether, a saturated hydrocarbon, an aromatic hydrocarbon, etc., or a mixture thereof. It dissolves organic tin compounds and tin fluoride compounds well, and the solvent itself does not generate harmful organic fluorine compounds during mixing.

In the composition of the present invention, the fluorine content is 0.01 to 10% in F/Sn weight ratio. If it is less than 0.01%, there is no effect, and even if it exceeds 10%, no further improvement in the effect is observed.

In the composition of the present invention, the amount of the tin compound is 0.01 to 45% in terms of 2% by weight of SnO based on the total composition.

This concentration is selected in consideration of the thickness of the film to be formed and other factors.

Usable solvents include alcohols having 1 to 20 carbon atoms, aromatic hydrocarbons such as benzene, toluene, and xylene;
Saturated hydrocarbons such as n-hexane and kerosene, esters such as ethyl acetate, butyl acetate and butyl acetoacetate, ketones such as acetone, methyl ethyl ketone and acetylacetone, β-diketones, ethyl ether, butyl ether, methyl cellulosolve, ethyl Cellulosolve, dioxane, ethers of tetrahydrofuran, etc. can be used singly or in combination of two or more. In order to improve the film-forming properties of the coating solution, it is preferable to prepare the coating solution by evaporating the solvent after the reaction between the tin compound and the tin fluoride compound, and then redissolving it in a solvent suitable for coating, such as ethyl acetate. In addition, formic acid,
Addition of a carboxylic acid such as acetic acid or addition of a very small amount of water may be effective in some cases.

In the composition of the present invention, SnFn(OR), , SnF
(OH)(OR)z, SnFz(OH)(OR),
[SnF(OR-),)zOlSnCIF(OR)z,
It is presumed that compounds such as (R, m, n, l, and o are as described above) are generated.

Methods for applying the composition prepared in this way include a spinner method, a spray method, and a dipping and pulling method.

Although conventional application techniques such as brush application can be used,
The immersion-pulling method is preferable because it allows large substrates to be treated in large quantities. In this case, the concentration of the coating liquid and the pulling speed are adjusted depending on the desired film pressure.

After coating the substrate in this way, it is dried at 50 to 150°C for 10 minutes to 1 hour, and then baked at 400 to 600°C for 3 to 30 minutes in the air or oxygen atmosphere to form a transparent conductive material on the substrate. A film can be formed. - If sufficient film thickness, conductivity, etc. cannot be obtained after two treatments,
Improvements can be made by repeating similar processing.

Example 1 Sn(OR) shown in Table 1, SnC1rl(OR)
In a 10% n-hexane solution of 4-n (n = 1-3), n
- Slowly add SnF4 suspended in hexane in the amount shown in Table 1 at room temperature, heat under reflux for 30 minutes, first evaporate the solvent, then add ethyl acetate and dissolve by heating,
Insoluble materials were filtered off to obtain a pale yellow, transparent solution. A glass substrate was immersed in the solution, applied at a pulling rate of 20 μ/min, dried in the air for 15 minutes, further dried at 150°C for 15 minutes, and finally baked at 500°C for 30 minutes. Ta. The physical properties of the films thus formed as shown in Table 1 were investigated.

Example 2 13.70 g of tin octylate was dissolved in 45 aJ of ethyl acetate and 5 - of acetylacetone, and after refluxing, various tin fluoride compounds shown in Table 2 were added, and after further refluxing, the following Example 1 was prepared. Processing and testing were carried out in the same manner. The results are also shown in Table 2.

Example 3 Various tin fluoride compounds shown in Table 3 were added to a solution of tin acetylacetone in isopropyl alcohol.

After refluxing, the following treatments and tests were performed in the same manner as in Example 1. The results are also shown in Table 3.

〔Effect of the invention〕

As shown above, the composition of the present invention provides a tin oxide coating having good transparency and strength of about 7×10 2 to 2×10 3 Ω/mouth by adding a tin fluoride compound.

Furthermore, the amount of tin fluoride compound added can be as small as 0.01 to 10.0% in F/S mouth weight ratio in terms of fluorine, and the generation of corrosive fluorine compounds that sometimes occur during baking is minimized. , has practical advantages.

Claims (1)

[Claims] Monovalent, divalent or tetravalent tin alkoxide, organic acid tin, tin β
- consists of at least one type of diketone complex, a divalent or tetravalent tin fluoride compound having an Sn-F bond, and a solvent, and has a fluorine content of 0.01 to 10.0 in F/Sn weight ratio.
0% transparent conductive film forming composition. 2. The composition according to claim 1, comprising: 2.
The valent or tetravalent tin alkoxide is an organic acid tin, a tin β-diketone complex is Sn(OR)_2 (R is a lower alkyl group,
Same hereafter), Sn(OR)_4, SnCl_n(OR)
_4_-_n (n=1 to 3), SnCl(OH)(OR
)_2, SnCl_2(OH)(OR); ▲There are mathematical formulas, chemical formulas, tables, etc.▼; From the group consisting of Sn(A-A)_2 (A-A is a substituted or unsubstituted β-diketone, the same applies hereinafter) A transparent conductive film-forming composition that is selected. 3. The composition according to claim 2, comprising S
Tetravalent tin compounds with n-F bonds are SnF_4, Sn
F_n(OR)_4_-_n (R is a lower alkyl group, the same applies hereinafter, n = 1-3), SnCl_mF_n(OR)_
(_4_-_m_-_n_) (1≦m<4, 1≦n<4
and m+n<4), SnF_2(A-A)_2, Sn
F_2(OOCR)_2, SnF_nR_(_4_-_
A transparent conductive film-forming composition selected from the group consisting of n_) (n=1 to 3). 4. The composition according to any one of claims 1 to 3, wherein the solvent is an alcohol, ester, ketone, β-diketone, ether, or saturated hydrocarbon having 1 to 20 carbon atoms. , an aromatic hydrocarbon, or a mixture thereof.