JPS6121919A - Manufacture of tungsten oxide film - Google Patents

Abstract

PURPOSE:To obtain a tungsten oxide film useful especially as an electrochromic (EC) material by applying a soln. contg. one or more kinds of chlorotungsten alkoxides to a substrate and by carrying out heat treatment. CONSTITUTION:Tungsten chloride such as WCl6 or WCl5 is reacted with corresponding metallic alkoxide [M(OR)n (M is a metal such as Na or K)] to produce chlorotungsten alkoxide represented by the formula (where R is 1-10C alkyl or alkoxyalkyl, 1<=n<=5, and 1<=m<=4), e.g., W(OC3H7)5Cl. A soln. of the produced alkoxide in a solvent such as isopropanol is sprayed on a substrate such as electrically conductive glass with a spray gun. The resulting film on the substrate is heat treated at 20-400 deg.C, especially 50-300 deg.C at which crystallization proceeds hardly to obtain a transparent tungsten oxide film adhered firmly to the substrate. An EC material having superior mass production ratio, homogeneity, work efficiency and economical efficiency and applicable to various fields can be easily obtd. by using the tungsten oxide film.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for forming a tungsten oxide film on a substrate, and particularly to an electrochromic (hereinafter abbreviated as EC) method.
The present invention relates to a method for manufacturing a tungsten oxide film useful as a material.

Prior Art Tungsten oxide film is well known as a good Xa material, and its manufacturing method is based on solid oxide (Won
), evaporation methods and sputtering methods using resistance heating or electron beam irradiation are common. however,
These methods require large capital investment because they use expensive high-vacuum equipment, and have drawbacks such as not being suitable for mass production. Furthermore, in actual work, these methods require a high vacuum in the deposition chamber to improve reproducibility, and depending on the capacity of the pump, a high load is applied, making maintenance management of the apparatus complicated. Furthermore, high purity is required for the vapor deposition materials, as even small amounts of impurities may be concentrated on the substrate, and high purity products are required because they may gasify and fluctuate the pressure inside the vapor deposition chamber. . Regarding the vapor deposition conditions, the temperature at which the substrate is heated, the vapor deposition rate, the pressure during vapor deposition, etc. have a great influence on the structure and physical properties of the B110 substance that adheres to the substrate, so it is necessary to accurately control various conditions. Even if the conditions are maintained, the temperature distribution,
Various distributions such as evaporation rate distribution, evaporation film thickness, etc. occur,
It is extremely difficult to maintain uniform quality at all times. Therefore, in consideration of eliminating such drawbacks such as mass production, homogeneity, workability, economic efficiency, etc. and increasing the area, we developed a method using a tungsten-based chemical that does not produce tungsten e-oxide through decomposition heat treatment, but also provides excellent NA properties. Methods for producing tungsten oxide films have been proposed, such as the CVD method, spray method, roll coating method, spin code method, and dipping method. Such a drug is W(004HI)11 + W(008H17)@<
*Kaikai No. 55-80482), W(0(J(3)a,
W(OOsHs)a(Unexamined Lid 56-38379
No.) Drugs such as tungsten alkoxide and tungsten phenoxide have been reported. However, the above-mentioned tungsten alkoxide is easily decomposed by moisture in the air, and its AH is not necessarily easy. In addition, the produced film cannot be said to have excellent transparency, and especially when tungsten phenoxide is used, the coloration is noticeable, and transparent GC films cannot be used in fields that require tungsten chloride films. The problem was that seven application fields were restricted.

The purpose of the present invention is to solve the drawbacks of the above-mentioned conventional methods.In particular, it facilitates expansion of area, improves mass productivity, homogeneity, The purpose of this invention is to easily obtain an EC material that has excellent workability and economic efficiency and can be applied in many fields.

Means for Solving the Problems The present invention provides the general formula W(OR)nOIV, 6-n or W
(OR) m(Us In (where R represents an alkyl group or alkoxyalkyl group having 1 to 10 carbon atoms, !≦n
This method of producing a tungsten oxide film is characterized by applying a solution containing at least one type of tungsten chloride alkoxide (1≦5, l≦m≦4) to a substrate and heat-treating the solution.

The tungsten chloride alkoxide used in the present invention is Wc4. , We et al., metal alkoxides corresponding to tungsten chloride [M(OR)n, M: Na.

It can be easily synthesized by reaction with tungsten chloride or an alkoxytrialkylsynthine corresponding to tungsten chloride. In these reactions, organic solvents such as alcohols, hydrocarbons, halogenated hydrocarbons, ketones, and carbon disulfide are generally used, and the solvent bath solution of tungsten chloride alkoxide 6 obtained in the reaction is used to remove by-products such as common salt from the reaction. If it contains solid content, it is separated and used as a WO1 forming agent in spraying, roll coating, spin-coding, CVD, dipping, and other methods. At that time, depending on the requirements, the concentration can be adjusted to a desired concentration by concentration by vacuum distillation, atmospheric distillation, etc., dilution with a solvent, etc., and then used.

Other types of solvents other than those used in the reaction as film quality improvers include n-propyl alcohol, isozorobyl alcohol, n-butyl alcohol, isobutyl alcohol, tertiary butyl alcohol, and ethyl acetate. , inzolobyl acetate, n-zolobyl acetate, tert-butyl acetate, benzene, toluene, etc. can also be added and used as necessary.

In the formation of a film using a tungsten chloride alkoxide-based chemical in the present invention, conductive glass, plastic, or ceramic 4i k is used as a substrate, and a spray method, roll coating method, spin code method, CVD method, dipping method, or screen printing method is used. Any method that can coat a film on a substrate can be applied.

Furthermore, the tungsten chloride alkoxide used in the present invention can be produced by various manufacturing methods, such as w(003
H7)6 C1 is ≠ thorium isopropoxide and WC
1! .
(, ), an isozorobyl alcohol rG solution of aJl is obtained.

Using a spray method as an example of the method of operation, an example of a method for manufacturing a tungsten oxide film using conductive glass as a substrate will be shown, and its operation will be explained. A tungsten chloride alkoxide-based chemical prepared to a predetermined degree is sprayed onto the four-electrode glass using a tin gun. The chemical adhering to the substrate forms a film by hydrolysis of tungsten chloride alkoxide, volatilization of the solvent, etc.

Since such a film contains a solvent, decomposed fragments of tungsten chloride alkoxide, moisture, etc., in order to obtain a transparent tungsten oxide film that is strongly adhered to the substrate, the film is heated at a temperature range of 20 to 400℃ below room temperature where crystallization does not proceed. C., preferably 50 to 300.degree. C., it is possible to form a transparent tungsten oxide film that firmly adheres to the substrate. The present invention will be specifically explained below with reference to Examples.

Example 1 NFiSA glass (20λ x 50~) was immersed in an isopropyl alcohol solution of w(oc3a,) and an (WOsm calculated concentration 8y/100m1+), and after being pulled up, the glass was heated at 20°C to perform decomposition, volatilization of the solvent, etc. Air dry for 10 minutes and then! After heat treatment at 50° C. for 10 minutes and cooling to room temperature, the WO film on one side of the test piece was wiped with dilute alkaline water to obtain a transparent acid imhotungsten film. The average transmittance in the visible region was about 79%, a value close to the transmittance of the substrate (80 inches).

When the surface was observed under a microscope, it was found to be a dense and good film.
The film thickness was 2000λ. When the EOe properties were measured in a 1 molar lithium perchlorate propylene carbonate electrolyte using platinum as a counter electrode, the responsiveness of color development and fading was good.

Furthermore, even if the adhesive tape was firmly attached to the membrane and then suddenly removed, the membrane did not peel off, and a strongly adhesive membrane was formed.

Example 2 NESA by spraying w(oc,n5)4c1 dissolved in ethyl alcohol-isozorobyl alcohol (C鵞H,0H10,H,OH valley volume ratio = 1°wo, Kyofun fA degree 7ri/100d) Apply to glass (207, x 50X) 2
The film was air-dried at 0°C for 5 minutes, and then heat-treated at 130°C for 15 minutes to obtain a transparent tungsten oxide film. The average transmittance in the visible region was about 80 inches, which was close to the transmittance of the substrate (82%), and the film thickness was 3300λ.

As a result of measuring me characteristics according to Example 1, the responsiveness of color development and fading was good. Furthermore, the surface of the film was dense and the adhesion to the substrate was strong.

Example 5 W(003Hy) 40μ Improvil Alcohol-n
-Butyl alcohol solution (0xHtOH104H@OH
Volume ratio = 8/2, To, %jn#[10/100
NFiSA glass (20% x 50%, masking tape attached to one side) was immersed in 20% x 50% m1), pulled up, and then decomposed.
In order to volatilize the solvent, the film was air-dried at 25° C. for 10 minutes, and after the masking tape was removed, it was heat-treated at 180° C. for 15 minutes to obtain a transparent tungsten oxide film. The thickness of this film is 2
It happened after 400'h. The average transmittance in the visible range is approximately 7
The transmittance was 9%, which was close to the transmittance of the substrate (80%).

As a result of measuring the EC characteristics according to Example 1, the responsiveness of color development and fading was good, and the reeds, the denseness of the surface of the film, and the adhesion of the film to the substrate were all good.

Example 4 Isopropyl alcohol solution of W (003H,), Cμ (concentration in terms of W03: 7/100d) f N ES
It was coated on A glass (20% x 50%) using a spin code method, air-dried at 20°C for io minutes to decompose, volatilize the solvent, etc., and then heat-treated at 150°C for 15 minutes to obtain a transparent tungsten oxide film. .

The film thickness was 3200λ, and the average transmittance in the visible region was about 79cm, a value close to the transmittance of the substrate (81%).

The responsiveness of color development and fading was good.

Example 5 W(oc, H4ocH3)4ax, isozorobyl alcohol-methoxyethyl alcohol m solution (03H,0H
10H300H2C! H,OH volume selection ratio = s/2,
WO3 equivalent concentration 39/100) and N) iisA glass (
20$X 50λ) and then pulled out at 25℃-10
It was air-dried for 1 minute, then heat-treated at 200° C. for 10 minutes, and the WO3 on one side was wiped off in the same manner as in Example 1 to obtain a transparent tungsten oxide film.

The film thickness was 800λ, and the average transmittance in the visible region was about 79%, a value close to the transmittance of the substrate. When EC% was measured, the responsiveness of color development and fading was good.

Example 6 A sample was soaked, air-dried, and heat-treated in accordance with Example 1, turned over twice, and the WO and film on the back were wiped off with dilute alkaline water.
A transparent tungsten oxide film was obtained. This film thickness is 4I00λ
The average transmittance in the Kaicho viewing area was about 78%. Further, when 30% property was measured, the responsiveness of color development and fading was good.

Comparative Example 1 Sodium ethoxide (0,378 mol) and wci6 (
0,065 mol) in ethyl alcohol,
After separating the solid content such as salt in the reaction product, the filtrate was condensed under reduced pressure to obtain an ethyl alcohol solution of w (uc, J (,) (WO8 conversion fi@Ij?p/100 resistance) icNK
sA glass (20λX50'X) was immersed, pulled up, air-dried at 25°C for 10 minutes, further heat-treated at 150°C for 10 minutes, and the WO on one side was wiped off in the same manner as in Example 1. This film thickness was reduced after 2000 people, and the resulting film was partially cloudy.

When the EC characteristics were measured, it was found that the responsiveness of color development and fading was not good and some color remained.

Comparative Example 2 Hexachloride/Gesten'P, n-hexane 15wf7
The sample was collected and mixed in a container. This solution was dropped onto NkSA gas (zo>x5oX) using a dropper, and after removing excess e and f, it was air-dried at 20°C for 5 minutes and heat-treated at 150°C for 10 minutes.

The obtained film had a thickness of 2000 K and was cloudy.

Effects of the Invention According to the method of the present invention, a tungsten oxide film with excellent EC characteristics can be easily obtained, and the area can be easily increased, and mass production is possible.
In addition to being excellent in workability, the obtained film is a homogeneous film, and in particular, has excellent transparency, so that it can provide a film that can be widely applied to various uses.

Claims (1)

[Claims] General formula W(OR)_nCl_6_-_n or W(OR
)_mCl_5_-_m (where R represents an alkyl group or alkoxyalkyl group having 1 to 10 carbon atoms, and 1≦n
A method for producing a tungsten oxide film, comprising applying a solution containing at least one kind of tungsten chloride alkoxide having the following formulas (≦5, 1≦m≦4) to a substrate and heat-treating the solution.