JPS6144949B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for treating a titanium oxide film, and more particularly to a method for treating a titanium oxide film formed from an alkyl titanate. Titanium oxide films are used as high refractive index dielectric films in various fields such as surface antireflection films for glass products, transparent conductive films, selective light transmitting films, insulating films for chemical capacitors, and surface modification films for organic base materials. It has been applied in Generally, methods for constructing titanium oxide films in this field include physical methods such as vacuum evaporation and sputtering, and chemical methods such as anodization, thermal oxidation, and coating with organic titanates. Targeted film forming means is a promising method in terms of ease of equipment and operation, and economical efficiency. By the way, when a titanium oxide film formed from such alkyl titanate is used as a component of a transparent conductive film, a selective light transmitting film, etc.,
Depending on the field of use, further improvement in visible light transmittance is required. The present inventor conducted intensive research to improve the drawbacks of such a titanium oxide film, and found that by treating it with a specific amino compound or amino alcohol compound, the visible light transmittance was greatly improved. The present invention was achieved by discovering that the infrared reflectance of the infrared rays does not decrease. That is, the present invention provides a titanium oxide film formed from 1 alkyl titanate according to the following general formulas () and (). [However, in the above two formulas, R represents a hydrogen atom or a methyl group, n is an integer of 1 to 5, and m is 1 to 3.
represents an integer. ] A method for treating a titanium oxide film, comprising contact treatment with at least one compound selected from the group consisting of amino compounds and aminoalcohol compounds represented by: 2. The processing method according to item 1 above, wherein the titanium oxide film is provided on at least one metal thin film and/or metal oxide thin film provided on the molded product substrate A, and 3. The titanium oxide film is formed The above is a transparent high refractive index dielectric thin film layer B provided on the object substrate A, and a high refractive index dielectric thin film layer D further provided on the metal thin film layer C containing silver and/or gold as a main component. Second
This is the processing method described in the section. The titanium oxide thin film layer in the method of the present invention is provided using a solution of a solute containing an alkyl titanate as a main component, usually an organic solvent solution. Examples of alkyl titanates include tetraalkyl titanates and/or condensates thereof. The alkyl group of the tetraalkyl titanate is not particularly limited, and examples thereof include ethyl, propyl, isopropyl, butyl, 2-ethylhexyl, stearyl, and the like, among which propyl and butyl are preferably used. These condensates are obtained by condensing two or more tetraalkyl titanates. For example, the expression [However, in the formula, R represents an alkyl group, and m is a positive integer. ] It is a compound represented by the following or a mixture thereof, and from the viewpoint of ease of handling, m is preferably 10 or less. In particular, dimers, tetramers, decamers, etc. of tetra-n-butyl titanate and tetrapropyl titanate are preferably used from the viewpoint of coatability. The titanium oxide thin film according to the present invention can be formed by dissolving a predetermined amount of the alkyl titanate in a solvent and applying a solution obtained on the molded substrate, followed by drying and heat treatment. The molded substrate used may be a molded product of a transparent organic polymer material; a molded product of an inorganic material such as glass or metal oxide; or a composite of both; however, depending on the industrial productivity. From this point of view, it is preferable to use an organic polymer substance, and in particular, a film-like material is preferable. In particular, polyethylene terephthalate film, nylon film, polycarbonate film, polyethylene film, etc. are practically preferred. The solvent used in the coating solution should have solute solubility and evaporability (preferably boiling point below 150℃)
and inertness (does not inactivate the three-dimensional reticulation reaction by reacting with the solute). n-heptane, cyclohexane, toluene,
Hydrocarbons such as xylene, general-purpose solvents such as ethyl alcohol, isopropyl alcohol, butanol, or mixed solvents thereof are particularly preferred. In the present invention, since water plays an effective role in promoting three-dimensional reticulation of the coating film, a small amount of water may be present in the coating solution. In addition, in order to obtain stability of the coating solution, acetylacetone, acetoacetate, diacetone alcohol, lactic acid, glycolic acid, etc. should be added to the above solution.
It is also effective to add a known chelating agent such as an oxyacid. Particularly when the alcoholic solvent contains a small amount of water, the addition of the chelating agent is particularly effective in suppressing hydrolysis of the coating solution and improving coating properties and storage stability. The coating method is not particularly limited, and can be a general method, that is, applying a solution diluted with a solvent, or a general coating method such as a dipping method, a spray method, a spinner method, or a machine coating method such as gravure coating. I can do it. The amino compound used in the present invention has the general formula:

[Formula] (wherein R is a hydrogen atom or a methyl group, n is 1 to 5), and amino alcohol is

It is represented by the formula: (wherein R is the same as defined above and m is an integer of 1 to 3).
These compounds generally have the ability to strongly coordinate with various metals. In the present invention, the function of improving transmittance by treatment with such an amino compound is not clear, but when forming a titanium oxide layer by a network reaction of alkyl titanate, it is possible to It is thought that chelation of the amine or amino alcohol is involved. Preferably used amino compounds include ethylenediamine, diethyltriamine, triethylenetetramine, and tetraethylenepentamine, and aminoalcohols include ethanolamine, diethanolamine, and triethanolamine. Treatment methods with such amino compounds or amino alcohols generally include coating or spraying a solution of the compound dissolved in water or an organic solvent, or
It can also be done by immersing it in a solution. Of course, it is better to remove the excess amino compound and solvent by washing or drying after treatment. The organic solvent used for treatment may be any organic solvent as long as it dissolves the amino compound and can be easily removed by drying, washing, etc. after treatment. Suitable examples include methanol, ethanol, n-propanol, isopropanol,
Alcohols such as butanol, ethyl ether,
Chain and cyclic ethers such as propyl ether and tetrahydrofuran; ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; esters such as ethyl acetate, butyl acetate and isobutyl acetate; carbonized halides such as methylene chloride, chloroform and carbon tetrachloride; Examples include hydrogen. Solution concentration is not particularly limited, but is generally 0.1%~
20%, preferably a range of 0.5% to 10% is used. If it is less than that, there is no treatment effect, and if it is more than that, there is no effect of increasing the concentration. Processing temperature is room temperature ~ 80℃
℃, preferably in the range of room temperature to 50 ℃ is generally used. The method for treating a titanium oxide film of the present invention exhibits remarkable effects when the titanium oxide film defined by the present invention is applied to a transparent conductive film or a selectively transparent film. Examples of the light-transmissive film include those in which at least one thin film of metal or metal oxide is laminated on a molded substrate. For example, (a) molded product substrate/titanium oxide film; (b) molded product substrate/metal or metal oxide film/titanium oxide film; (c) molded product substrate/titanium oxide film/metal or metal oxide film (d) Examples include structures such as molded product substrate/metal oxide film/metal film/titanium oxide film. In the above configuration, if the titanium oxide film is exposed on the surface, the contact treatment may be performed as is, but if the titanium oxide film is inside, it is preferable to perform the contact treatment after the titanium oxide film is formed, and then further perform the contact treatment. It is preferable to form a film. Materials for the metal film used in each of the above configurations include gold, silver, copper, aluminum, nickel, palladium, etc. alone or an alloy of two or more, preferably gold, silver, or a main component of these. Gold, silver alone, or an alloy thereof is particularly preferred. Examples of metal oxides include titanium oxide, zirconium oxide, bismuth oxide, tin oxide, and indium oxide, with indium oxide and tin oxide being preferred, and indium oxide being particularly preferred. Therefore, preferred laminates to which the present invention is applied include the following, where the titanium oxide film formed from alkyl titanate is TiO ₂ (TAT) and the molded substrate is Base. (a)-(1) Base/TiO ₂ (TAT), (b)-(1) Base/Ag or Ag alloy/TiO ₂ (TAT), (b)-(2) Base/Au or Au alloy/TiO ₂ (TAT), (b)−(3) Base/Indium oxide/TiO ₂
(TAT), (c)-(1) Base/TiO ₂ (TAT)/Ag or Ag alloy, (c)-(2) Base/TiO ₂ (TAT)/Au or Au alloy, (d)-(1 ) Base／TiO ₂ (TAT)／Ag or Ag alloy／TiO ₂ (TAT) (d)−(2) Base／TiO ₂ (TAT)／Au or Au alloy／TiO ₂ (TAT), (d)−( 3) Base/TiO ₂ /Ag or Ag alloy/TiO ₂
(TAT), (d)−(4) Base/TiO ₂ /Au or Au alloy/TiO ₂
(TAT), (d)-(5) Base/TiO ₂ (TAT)/Ag or Ag alloy/TiO ₂ , (d)-(6) Base/TiO ₂ (TAT)/Au or Au alloy/TiO ₂ above In (d)-(1) to (d)-(6), molded product substrate A/
This corresponds to the structure of high refractive index dielectric thin film layer B/metal thin film layer C/high refractive index dielectric thin film layer D, but in this structure, high refractive index dielectric thin film B or D is formed by vacuum deposition, sputtering, etc. In addition to titanium oxide, zirconium oxide, bismuth oxide,
Examples include zinc sulfide, tin oxide, and indium oxide, and among these, titanium oxide is preferred. Among these films, the high refractive index dielectric thin films B and D have a thickness of 50 to 1000 Å, preferably 100 to 500 Å,
The metal thin film C has a thickness of 30 to 500 Å, preferably 50 to 200 Å. Among the various laminates mentioned above, the most preferable one is TiO ₂ (TAT) as a high refractive index dielectric thin film layer B on a transparent molded substrate A, a metal or alloy thin film layer C, and a high refractive index dielectric. _TiO2 as thin film layer D
(TAT), and it is preferable to apply the present invention to this multilayer laminate. A particularly preferable example of such a laminate is represented by (B)/(C)/(D) as follows. (d)−(7) TiO ₂ (TAT)/Ag/TiO ₂ (TAT) (d)−(8) TiO ₂ (TAT)/Au/TiO ₂ (TAT) (d)−(9) TiO ₂ ( TAT)/Ag-Cu/ _TiO2
(TAT) (d)−(10) TiO ₂ (TAT)/Ag−Au/TiO ₂
(TAT) (d)-(11) TiO ₂ (TAT)/AgS-containing Ag or Ag alloy/TiO ₂ (TAT) According to the present invention, the above-mentioned laminate whose optical performance has been improved can further be protected on the surface. By adding a coating, its practicality can be further enhanced. The selective light transmitting laminate thus obtained can be used for freezing and refrigerating cases, windows of buildings and ordinary homes, greenhouses, etc. due to its excellent transmittance and heat ray reflecting ability. A more specific explanation of the present invention will be given below using Examples. In the Examples, the light transmittance is a value at a wavelength of 500 nm unless otherwise specified. The infrared reflectance is measured by attaching a reflectance measurement device to a Hitachi EPI-type infrared spectrometer and measuring the reflectance of a slide glass with a sufficiently thick layer of vacuum-deposited silver (approximately 3000 Å).
Measurements were made at 10μ unless otherwise specified as 100%. Examples 1 to 2 Transparent molded substrate A is a biaxially stretched polyethylene terephthalate film with a light transmittance of 86% and a film thickness of 50 μm, and a titanium oxide thin film layer with a thickness of 300 Å as layer B.
A thin film layer of silver and copper alloy (92% by weight, 8% by weight of copper) with a thickness of 170 Å as the C layer and a titanium oxide thin film layer with a thickness of 300 Å as the D layer were sequentially laminated,
A laminate having selective light transmittance was obtained. The titanium oxide thin film layer is made of 3 parts of tetrabutyl titanate and 97 parts of isopropyl alcohol.
Coat a solution consisting of 3 parts with a bar coater at 120℃.
Heat and set for a minute. The metal thin film layer was formed by vacuum deposition using a resistance heating method using a silver-copper alloy (70% silver, 30% copper). The content of butyl groups contained in the titanium oxide thin film layer was determined to be 4.5% by the mass fragment graphics method (Mass No. 56). The visible light transmittance (0.5μ) of the obtained film is
The infrared reflectance of 4μ, 6μ and 10μ was 98%, 97% and 98%, respectively. The obtained film was heated to 20°C and 50°C in an ethylenediamine 0.5 mol/isopropanol solution.
Each sample was immersed in a 0.3 mol triethanolamine/isopropanol solution for 10 minutes, then thoroughly washed with water and dried to observe changes in optical properties. Table 1 shows the results.
I wrote it down.

[Table] Comparative Examples 1 to 2 For comparison, a laminate with selective light transmittance formed in the same manner as in Example 1 was immersed in water and isopropanol set at 20°C and 50°C for 10 minutes, and the optical properties were measured. The changes are shown in Table 2.

[Table] As seen in Comparative Examples 1 and 2, when treated simply with water or alcohol, no improvement in optical properties was observed. Examples 3 to 4 Metal thin film layer C was made of gold and silver alloy (gold 7) with a thickness of 170 Å.
Example 1 except that the composition was composed of silver (93% by weight)
A selective light transmitting laminate was obtained in the same manner as above. Money,
The metal thin film layer made of a silver alloy was formed by low-temperature magnetron sputtering targeting gold and a silver alloy (7% by weight of gold, 93% by weight of silver). The visible light transmittance of the obtained film was 77% and the infrared reflectance was 95%. The obtained film was heated to 20℃ and 50℃ in ethylenediamine 0.5mol/isopropanol solution.
It was immersed in a 0.3 mol triethylenetetramine/ethanol solution for 10 minutes, then thoroughly washed with water, and then dried to observe changes in optical properties. The results are shown in Table 3.

[Table] Comparative Examples 3 to 4 For comparison, a laminate with selective light transmittance formed in the same manner as in Example 3 was immersed in ethanol and isopropanol set at 20°C and 50°C for 10 minutes. I saw a change in characteristics. The results are shown in Table 4.

[Table] As shown in Table 4, treatment with ethanol and isopropanol alone did not have any effective effect on optical properties.

Claims (1)

[Claims] 1. A titanium oxide film formed from an alkyl titanate is formed by the following general formulas () and (). [However, in the above two formulas, R represents a hydrogen atom or a methyl group, n represents an integer of 1 to 5, and m represents an integer of 1 to 3. ] A method for treating a titanium oxide film, comprising contact treatment with at least one compound selected from the group consisting of amino compounds and aminoalcohol compounds represented by: 2. The processing method according to claim 1, wherein the titanium oxide film is provided on at least one metal thin film and/or metal oxide thin film provided on the molded product substrate A. 3. A transparent high refractive index dielectric thin film layer B on which the titanium oxide film is provided on the molded product substrate A, and a high refractive index dielectric film further provided on the metal thin film layer C containing silver and/or gold as a main component. The treatment method according to claim 2, wherein the body thin film layer D is a body thin film layer D.