JPH08254694A - Light-shielding thin film composition - Google Patents

Abstract

PURPOSE: To obtain a light-shielding thin film compsn. having excellent massproductivity and processing accuracy by incorporating a transparent liquid prepared by hydrolyzing a metal compd. having alkoxy groups and changing the compd. into a sol, a compd. which changes its color by heat, a coloring agent and a photosensitive resin. CONSTITUTION: This light-shielding thin film compd. contains a transparent liquid, a compd. which changes its color with heat, a coloring agent, and a photosensitive resin. The transparent liquid is prepared by hydrolyzing an alkoxy or at least one kind of metal compd. having alkoxy groups and changing the compd. into a sol. The coloring agent gives a complementary color to show a black color in a subtractive color process when the compd. which changes its color by heat changes its color. The metal compd. is preferably expressed by M(OR<1> )m(OR<2> )nXp Y<q> , wherein M is a metal selected from magnesium, calcium, titanium, etc., R<1> , R<2> are independently hydrogen atoms, chlorine atoms, etc., and m, n, p, q are integers 0 to 8 satisfying m+n>=1 and m+n+p+q = valence of M.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a composition for forming a light-shielding thin film and a light-shielding thin film. More specifically, a composition for forming a light-shielding thin film used for a display panel using liquid crystal or electroluminescence (hereinafter referred to as "light-shielding thin-film composition") and the composition formed using the composition. The present invention relates to a light shielding thin film.

[0002]

2. Description of the Related Art Conventionally, various kinds of light-shielding films used for display panels using liquid crystals and electroluminescence have been known, but until now, thin films having excellent smoothness and high optical density have been used. The light-shielding film that it had was limited. As such a light-shielding film, for example, a light-shielding film using a chrome film (already commercialized as hard chrome)
Or a light-shielding film using a chromium oxide film, and I on the transparent substrate
A TO film (tin-doped indium oxide film) is formed by a method such as sputtering or vacuum evaporation, and this ITO is formed.
A light-shielding film obtained by subjecting a film to electroless plating has been commercialized. In addition to these, a black pigment or dye (hereinafter referred to as "black pigment etc.") mixed with resin is used, and this is printed by the silk screen method, offset method, etc. There is known a light-shielding film formed by mixing a resin with a black pigment and the like and using a photolithography method (Japanese Patent Laid-Open No. 62-2473).
31 publication).

[0003]

However, the light-shielding film for forming the metallic chromium film or the ITO film requires a special and expensive device, and has a problem of poor mass productivity. Moreover, when seen through from the transparent substrate side,
Since the metallic luster is maintained as it is, it is unsatisfactory as the black mask of the display panel as described above.

A light-shielding film using a black pigment has no metallic luster, but when forming a light-shielding thin film by a photolithography method or the like, only pattern processing with a rough precision of about 100 μm can be performed, and the processing precision is high. There is a problem that is not good. When formed by a photolithography method, the processing accuracy is improved as compared with the case of forming by printing, but since a black pigment or the like interferes with photocuring of the photosensitive resin during exposure, There is a problem that the mixing ratio cannot be increased. Therefore, there is room for improvement in terms of light-shielding properties.

The present invention has been made to solve the problems of the prior art, provides a light-shielding thin film composition excellent in mass productivity and processing accuracy, and uses the light-shielding thin film composition excellent in light-shielding property. The purpose of the present invention is to provide a thin film.

[0006]

The light-shielding thin film composition of the present invention is a sol-ized transparent liquid obtained by hydrolyzing at least one metal compound having an alkoxy or acyloxy group; a thermochromic compound; When the thermochromic compound discolors, a colorant which gives a complementary color so as to give a black color by a color-reduction method; and a photosensitive resin. Thereby, the above object is achieved.

In a preferred embodiment of the present invention, the metal compound is represented by the following general formula: M (OR ¹ ) _m (OR ² ) _n X _p Y _q where M is magnesium, calcium, A metal selected from the group consisting of titanium, hafnium, germanium, zirconium, yttrium, aluminum, indium, gallium, tin, and silicon; R ¹ and R ² are each independently a hydrogen atom, an alkyl group,
Or an acyl group; X and Y are each independently a hydrogen atom, a chlorine atom or a hydroxyl group; and
m, n, p, and q are each an integer of 0 to 8,
m + n is greater than or equal to 1 and m + n + p + q is equal to the valence of M.

In a preferred embodiment of the present invention, the thermochromic compound discolors when heated to lose water of crystallization.

In a preferred embodiment of the present invention, when the composition is coated on a transparent substrate, dried, and exposed by photolithography, the light transmittance at the exposure wavelength is 5% or more. The thermochromic compound and the colorant are included in the composition in amounts such that

In a preferred embodiment of the present invention, the total weight of the thermochromic compound and the colorant is 100 parts by weight of a sol solution containing the photosensitive resin and the solized transparent liquid. And in the range of 5 to 50 parts by weight.

Further, the present invention is a light-shielding thin film formed on at least a part of a transparent substrate, which is obtained by forming a thin film of the above-mentioned light-shielding thin film composition on a transparent substrate and baking it. The total reflectance of the thin film portion as seen through the surface is 1.5% or less and the optical density is 3.0 or more. Thereby, the above object is achieved.

The light-shielding thin film composition of the present invention comprises a transparent liquid obtained by hydrolyzing a metal compound having an alkoxy or acyloxy group to form a sol, a thermochromic compound and a colorant.
A photosensitive resin and other additives are contained in a predetermined ratio.

The at least one metal compound having an alkoxy or acyloxy group used in the present invention is represented by the following general formula: M (OR ¹ ) _m (OR ² ) _n X _p Y _q (wherein M Is a metal selected from the group consisting of magnesium, calcium, titanium, hafnium, germanium, zirconium, yttrium, aluminum, indium, gallium, tin, and silicon; R ¹ and R ² are each independently Hydrogen atom,
An alkyl group or an acyl group; X and Y are each independently a hydrogen atom, a chlorine atom or a hydroxyl group; and m, n, p and q are each an integer of 0 to 8 and m + n is 1 And above, and m + n + p +
q is equal to the valence of M). This compound may be utilized as a mixture of one or more. Examples of the metal compound represented by the above general formula include tetraethyl orthosilicate, aluminum isopropoxide, titanium tetrabutoxide, zirconium tetrabutoxide, and the like. Alternatively, these partial hydrolysates can also be used.

The metal compound used in the present invention may be contained in the range of 0.5 to 10% by weight based on the total weight of the composition of the present invention. Preferably 2.0 to 7.0% by weight
And more preferably 1.5 to 3.0% by weight. If it is less than 0.5% by weight, a sufficiently thin porous film cannot be formed, which is not preferable. If it exceeds 10% by weight, a thin film cannot be formed uniformly, which is not preferable.

When the metal compound represented by the above general formula is hydrolyzed in an aqueous acid solution and the hydrolyzate is stirred under strong acidity and high shearing force, a transparent and uniform gel is formed. Of course, it is not limited to this as long as it forms a hydroxide sol by other hydrolysis and forms a porous transparent film by firing.

Acids that can be used for hydrolysis include acetic acid,
Examples thereof include hydrochloric acid, sulfuric acid and nitric acid.

The thermochromic compound used in the present invention is preferably a metal complex compound, a metal sulfate or a metal chloride, which loses water of crystallization and changes color when heated (for example, at 160 ° C. for about 10 minutes). As the metal complex compound, nickel-hexamethylenetetramine complex chloride decahydrate, cobalt-hexamethylenetetramine complex chloride decahydrate, cobalt-hexamethylenetetramine complex sulfate heptahydrate, cobalt- Hexamethylenetetramine complex thiocyanate tetrahydrate, cobalt-hexamethylenetetramine nitrate decahydrate, cobalt-hexamethylenetetramine iodide octahydrate, cobalt-hexamethylenetetramine bromide decahydrate, Examples thereof include cobalt borate tetrahydrate, cobalt potassium phosphate monohydrate, and cobalt ammonium phosphate monohydrate. Examples of the metal sulfate include cobalt sulfate heptahydrate, and examples of the metal chloride include cobalt chloride hexahydrate.

As the coloring agent used in the present invention, a pigment or a dye can be used. The color of the pigment or dye is selected so that when the thermochromic compound is heated and discolored, a complementary color is provided by the subtractive color method so that the light-shielding thin film exhibits a black color as a whole.

As the pigment, an azo lake type, insoluble azo type, phthalocyanine type, quinacridone type, dioxazine type, isoindolinone type, berynone type, anthraquinone type or perylene type organic pigment, or a mixture of these organic pigments; or Mention may be made of inorganic pigments such as myroline blue, iron oxide, cobalt-based, manganese purple, ultramarine blue, navy blue, cobalt blue, cerulean blue, pyridian, emerald green, cobalt green, or mixtures of these inorganic pigments.

The dye is preferably an oil-soluble or oil-dispersible dye.

The thermochromic compound and the colorant have a light transmittance of 5 at the exposure wavelength upon exposure when the composition of the present invention is applied on a transparent substrate, dried, and processed by a photolithography method. It may be included in the compositions of the present invention in an amount such that it is at least%. The dry thickness of the composition coated on the transparent substrate varies depending on the components contained, the exposure intensity, etc., but is usually 1.0 to 2.5 μm. When the transmittance is 5% or less, the curing of the photosensitive resin contained in the composition of the present invention becomes insufficient.

With respect to 100 parts by weight of the above metal compound, the thermochromic compound is 0.1 to 1.2 parts by weight, preferably 0.1.
14-1.0 parts by weight, more preferably 0.1-0.8
Parts by weight, and the colorant may be used in the range of 0.1 to 0.6 parts by weight, preferably 0.14 to 0.5 parts by weight, more preferably 0.2 to 0.4 parts by weight. . If the thermochromic compound content is less than 0.1% by weight, the light-shielding property is insufficient, which is not preferable. If it is more than 1.2% by weight, the adhesion of the film is poor and it is not preferable. When the amount of the colorant is less than 0.1% by weight, the light-shielding property is insufficient, which is not preferable. If it is more than 0.6% by weight, the adhesion of the film will be poor, which is not preferable.

The weight ratio of the thermochromic compound to the colorant is such that when these are combined as described above, the composition of the present invention is applied onto a transparent substrate, dried and processed by photolithography. In the exposure, it is determined so as to satisfy the light transmittance of 5% or more at the exposure wavelength, but is usually 3: 1 to 1: 5, preferably 5: 2.
It is 3: 5, more preferably 2: 1 to 1: 1. When the ratio is out of the range of 3: 1 to 1: 5, black is not exhibited by the subtractive color method, which is not preferable.

The photosensitive resin that can be used in the present invention can be roughly classified into three types, that is, a resin having a photosensitive group, a resin obtained by adding a resin to a photosensitive compound, and a photopolymerizable resin. Any photosensitive resin and mixtures thereof may be used in the present invention.

As the resin having a photosensitive group, for example, a dichromic acid type photosensitive resin composition described in JP-B-32-1211, US Pat. No. 2,725,372 (19)
55) and M.M. M. Mlnsk, Journal of Applied Polymer Science, 30
2 (1959), a photodimerization type photosensitive resin can be mentioned. Examples of a photosensitive compound to which a resin is added include those disclosed in US Pat.
No. 852379 (1958), and 2940853.
Azide-based photosensitive resin described in No. 1960;
U.S. Patent Nos. 2063631 (1936), 2679
No. 498, Japanese Patent Publication No. 43-23684, Japanese Patent Publication No. 44
-6413, Japanese Patent Publication No. 47-1604, U.S. Pat. No. 3,050,502, Japanese Patent Publication No. 41-112121 and Japanese Patent Publication No. 42-14326; US Pat. No. 3,046,119. ,
No. 3106465, Japanese Patent Publication No. 38-18015,
Japanese Patent Publication No. 38-12083, US Pat. No. 35351
57, JP-B-45-9610 and JP-A-49.
Examples thereof include o-quinonediazide-based photosensitive resins described in JP-A-48403. Examples of the photopolymerizable resin include Japanese Patent Publication No. 39-1112, Japanese Patent Publication No. 40-2204, and Japanese Patent Publication No. 40-1210.
No. 4, a diacrylate-based photopolymerizable photosensitive resin; a photopolymerizable photosensitive resin containing pentaerythritol triacrylate described in JP-B-46-32714, JP-B-46-42450. A photopolymerizable resin containing methacrylic acid esters described in JP-A-51-58106, and a polymer having a carboxyl group in the side chain and further having a double bond described in JP-A-51-58106. Photopolymerizable resin; Japanese Patent Publication No. 46-460
Examples thereof include a photopolymerizable resin containing a polymer having an aromatic-substituted amino group in a side chain and a compound having a polyhalogenated methyl group described in JP-A No. Other than these, for example, Takahiro Tsunoda "Photosensitive Resin" (Publishing Society of Japan, published in 1972), "Photopolymers: Principles, Processes and Materials" (Regional Technical Conference of Society Of Plastics Engineers Institute, Ellenville, NY, 1973 and 1976), M.P. G. Harpem (MG
Halpem) “Plastics Printing ·
Plates Manufacturing Technology "(Noise
Dates Corporation (Noyes Date C)
and a photosensitive resin described in 1971, Park Ridge, NJ). In the present invention, it is preferable to use a photopolymerization type photosensitive resin as the photosensitive resin from the viewpoint of solvent resistance and film strength of the light shielding thin film to be formed. The photosensitive resin is based on 100 parts by weight of the metal compound.
0.002-0.6 parts by weight, preferably 0.02-0.
4 parts by weight, more preferably 0.08 to 0.2 parts by weight can be used. If the amount of the photosensitive resin is less than 0.002 parts by weight, a film having good adhesion cannot be formed, which is not preferable. If the amount is more than 0.6 parts by weight, a uniform and good film cannot be formed, which is not preferable.

The light-shielding thin film composition of the present invention may further contain various additives, if desired. Examples of such additives include reactive diluents, sensitizers, photopolymerization initiators, and thermal polymerization inhibitors.

As the reactive diluent, a photopolymerizable water-soluble polyfunctional monomer, a water-insoluble polyfunctional monomer, or a mixture of one or more of these can be used. As the water-soluble polyfunctional monomer,
N, N'-methylenebisacrylamide, N, N'-dimethylacrylamide, N, N'-dimethylaminopropylacrylamide, N, N'-dimethylaminoethyl acrylate, polyethylene glycol diacrylate, N, N'-dimethylaminoethyl Acrylate,
N, N'- dimethylamino ethyl methacrylate etc. can be mentioned. Water-insoluble polyfunctional monomers include triethylene glycol diacrylate, ethylene glycol diacrylate, dipropylene glycol diacrylate, polypropylene glycol diacrylate, tripropylene glycol diacrylate, glycerin diglycidyl ether diacrylate, glycerin diglycidyl ether triacrylate. Acrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate,
Further, methacrylates corresponding to these acrylates can be cited. The reactive diluent is preferably contained in the range of 10 to 200% by weight based on the weight of the photosensitive resin. More preferably 100 to 150
% By weight. If it is less than 10% by weight, the viscosity of the photosensitive resin is high when the respective components of the composition of the present invention are mixed.
It may be difficult to form a uniform thin film. Furthermore, since the crosslink density becomes insufficient, the solvent resistance and chemical resistance of the cured thin film are likely to be poor. On the other hand, if it exceeds 200% by weight, the cross-linking density of the thin film after curing increases, but at the same time it becomes brittle, which is not preferable.

As the sensitizer, an aliphatic amine, an aromatic amine or a mixture thereof can be used. Examples of the aliphatic amine include triethanolamine, methyldiethanolamine, triisopropanolamine, n-butylamine, N-methyldiethanolamine, diethylaminoethyl methacrylate and the like. Examples of aromatic amines include Michler's ketone, 4,4′-diethylaminobenzophenone, ethyl 4-dimethylaminobenzoate, (n-butoxy) ethyl 4-dimethylaminobenzoate, and isoamyl 4-dimethylaminobenzoate. The sensitizer is preferably contained in the range of 1 to 10% by weight based on the total weight of the photosensitive resin and the reactive diluent.
More preferably, it is 1.5 to 8% by weight. If it is less than 1% by weight, the effect of improving the sensitivity is not obtained, and if it exceeds 10% by weight, it remains in the thin film component and causes problems such as volume shrinkage of the thin film, which is not preferable.

Examples of the photopolymerization initiator include benzoin ether type benzyl, benzoin, benzoin alkyl ether, and ketal type benzyl dialkyl ketals, and acetophenone type 2,2'-dialkoxyacetophenone, 2-hydroxy-2-. Thioxanthone-based thioxanthones such as methylpropiophenone and pt-butyltrichloroacetophenone, 2-chlorothioxanthones, 2-alkylthioxanthones, 2,4-
Examples thereof include dialkylthioxanthone and 2-alkylanthraquinone. The photopolymerization initiator is 3 to 3 with respect to the total weight of the photosensitive resin and the reactive diluent.
It is preferably contained in the range of 15% by weight. More preferably, it is 3.5 to 10% by weight. If it is less than 3% by weight, the curing reaction of the light-shielding thin film composition of the present invention may be insufficient. On the other hand, if it exceeds 15% by weight, the unreacted photopolymerization initiator remains after the curing reaction to deteriorate the performance of the light-shielding thin film formed, which is not preferable.

Examples of the thermal polymerization inhibitor include p-methoxyphenol, hydroquinone, alkyl- or aryl-substituted hydroquinone, tertiary butyl catechol, pyrogallol, naphthylamine, β-naphthol,
Mention may be made of phenothiazine, pyridine, nitrobenzene, o-toluquinone, aryl phosphite.
The thermal polymerization inhibitor is preferably contained in the range of 0.01 to 0.3% by weight based on the total weight of the photosensitive resin and the reactive diluent. More preferably 0.05
Is in the range of up to 0.2% by weight. If it is less than 0.01% by weight, the reaction does not proceed stably, which is not preferable. 0.3% by weight
If the amount is larger, the planned polymerization does not proceed, which is not preferable.

The light-shielding thin film composition of the present invention may contain a leveling agent for improving the smoothness of the coating film and an antifoaming agent for suppressing the generation of bubbles during stirring, as long as the characteristics are not impaired. it can. Further, necessary additives can be blended in consideration of viscosity, stability during use and storage, and drying property during use.

In order to form a light-shielding thin film using the light-shielding thin film composition of the present invention, first, a mixed solution prepared by mixing the respective components of the composition of the present invention is applied onto a transparent substrate and dried. Next, when this is heated to change the color of the thermochromic compound, the coating film turns black by a color-reducing method with a colorant, and a light-shielding film is obtained. It is possible to easily form a light-shielding thin film having a desired pattern using the composition of the present invention. A photolithography method is preferably used for this. For example, as shown in FIG. 1, first, the composition of the present invention is uniformly applied to at least a part, usually the entire surface, of the transparent substrate 12 with a spinner or a roll coater to give a predetermined film thickness. The coating film 1 is formed. After drying this at a predetermined temperature, a photomask 13 having a predetermined pattern is fixed at a predetermined position on the substrate 12, and an ultraviolet ray 1 is applied from above the photomask 13.
4 to the coating film 1 of the composition (exposure). Then the first
As shown in FIG. 3C, this substrate 12 is developed to remove unnecessary portions of the coating film 1 of the composition. Then, the substrate 12
After washing, the substrate 12 is baked (heated) at a predetermined temperature for a predetermined time to obtain a black light-shielding thin film. Further, by baking at a high temperature for a predetermined time, the light-shielding thin film 15 made of an inorganic material having fine pores is formed on the substrate 12.

The first firing is preferably carried out at 110 to 180 ° C. More preferably 150
It is in the range of to 170 ° C. If the temperature is lower than 110 ° C, the loss of water of crystallization of the heat-denatured compound does not proceed completely, which is not preferable.
If it is higher than 180 ° C., uniform loss of water of crystallization is not carried out, so that a good thermochromic compound cannot be obtained, which is not preferable. Further, the firing time is 5 to 20 though it depends on the firing temperature.
The range of minutes is preferred. More preferably, it is in the range of 8 to 15 minutes.

The second firing is preferably performed in the range of 170 to 250 ° C. More preferably 180
It is in the range of to 210 ° C. If the temperature is lower than 170 ° C, the formation of the inorganic substance is not good, which is not preferable. If the temperature is higher than 250 ° C, a uniform inorganic substance film cannot be formed, which is not preferable. The firing time depends on the firing temperature, but is 1
The range of 0 to 50 minutes is preferable. More preferably 20-
It is in the range of 40 minutes.

The thickness of the thin film after firing is 0.5 to 10 μm.
It is preferably in the range of. More preferably 0.8
Is in the range of ˜5 μm. If it is thinner than 0.5 μm, it does not have a sufficient light-shielding property, which is not preferable. If it is thicker than 10 μm, a display defect occurs as a panel, which is not preferable.

[0036]

When a coating solution is prepared by using each component of the light-shielding thin film composition of the present invention, and this is coated on a substrate, dried, and heated, the thermochromic compound contained therein loses crystal water. At this time, the entire coating film becomes black for the first time due to subtractive color mixing of the compound and the color of the colorant after discoloration. Since the coating film is not black in the unheated state after the coating, the coating film can be sufficiently photocured by exposure of the coating film during pattern formation by the photolithography method. This is completely different from the case of the conventional light-shielding thin film composition containing a black pigment or the like. Therefore, according to the present invention, since the thermochromic compound and the colorant can be contained in the composition (1) in a larger amount than the conventional black colorant and the like, a light-shielding thin film having a high light-shielding effect can be obtained, 2) The ability of the coating film to be sufficiently photo-cured contributes to the improvement of the processing accuracy of the coating film after the photo-curing, and the light-shielding property of the obtained light-shielding thin film can be improved. It is possible to form a light-shielding thin film that is patterned accurately in various steps.

Since the hydrolyzate of the metal compound having an alkoxy or acyloxy group contained in the composition forms an inorganic substance having fine pores when the above coating film is baked,
The resulting thin film has a lower reflectance than the metal thin film and the thin film containing a black pigment due to the synergistic effect with the colorant.

Further, the total weight of the thermochromic compound and the colorant is adjusted to 5 to 50% by weight with respect to 100 parts by weight of the sol solution containing the photosensitive resin and the sol-ized transparent solution. By this, the thermochromic compound and the colorant reliably act to enhance the light-shielding property of the thin film formed from the light-shielding thin film composition, and the light-shielding thin film composition is applied onto the transparent substrate. When this happens, the adhesive force of the photosensitive resin ensures close contact with the transparent substrate. Therefore, the processing accuracy at the time of pattern formation by the photolithography method is further enhanced.

[0039]

EXAMPLES Hereinafter, the light-shielding thin film composition of the present invention will be described in detail with reference to Examples, but the present invention is not limited thereto.

In the examples and comparative examples of the present invention, as the thermochromic compound, cobalt hexamethylenetetramine complex chloride (decahydrate), cobalt hexamethylenetetramine complex sulfate (heptahydrate), or cobalt phosphate. (Octahydrate) was used. These are red, red, and pink before firing, and become blue, green, and blue after firing at 160 ° C. for 10 minutes, respectively.

In the examples and comparative examples of the present invention, since the thermochromic compound becomes blue or green after firing, a red pigment (azo metal salt red pigment, Sanyo Dye Co., Ltd.) was used as a colorant.

In Examples and Comparative Examples of the present invention, as the photosensitive resin, liquid RW- having a solid content of 15% by weight was used.
301 (manufactured by Sekisui Fine Chemical Co., Ltd.) was used.

As the additive, dipentaerythritol hexaacrylate was used as a reactive diluent, triethanolamine was used as a sensitizer, Irgacure # 907 was used as a photopolymerization initiator, and hydroquinone was used as a thermal polymerization inhibitor.

Table 1 shows the compositions of Examples 1 to 5 and Comparative Examples 1 to 10 of the present invention. In addition, Example 1
In 5 and Comparative Examples 1 to 5, the amount of each component is shown with the solution weight of the solified transparent solution as 100. Comparative Example 6
In 9 and 9, the amount of each component is shown with the solution weight of the photosensitive resin being 100.

Example 1 Using the compositions shown in Table 1,
A light-shielding thin film was formed by the photolithography method as follows.

As shown in FIG. 1A, first, a transparent substrate (for example, a glass substrate provided with ITO electrodes) 12
A light-shielding thin film composition was uniformly applied to the entire surface of the above using a spinner or a roll coater to a film thickness of about 2 μm to form a coating film 1 of the light-shielding thin film composition. After drying this at 70 ° C., as shown in FIG. 1B, a photomask 13 having a predetermined pattern to be described later is fixed at a predetermined position on the substrate 12, and ultraviolet rays 14 are emitted from above the photomask 13. The coating film 1 of the light-shielding thin film composition was irradiated for 60 seconds (exposure). Further, as shown in FIG. 1C, the substrate 12 was developed to remove the unexposed portion (uncured portion) of the coating film 1 of the light-shielding thin film composition.

Subsequently, after the substrate 12 is washed, the substrate 12 is baked (heated) at a temperature of 160 ° C. or higher for about 10 minutes or longer to form crystals of the thermochromic compound contained in the cured coating film. When water is lost, it becomes black by a decoloring method with a colorant, and when it is baked at 200 ° C. or higher for 30 minutes or longer, the light-shielding thin film 15 made of an inorganic material having fine pores is formed on the substrate 12. Formed on. The thin film thus formed is black and has a thickness of several nm to 100 nm.
It was a porous film having a large number of micropores having a size of about nm.

Before firing, the transparency in the visible light region and the ultraviolet light region was measured, and after firing, the visible light transmittance, resolution, tackiness, contrast, total reflectance and optical density were measured and evaluated. Table 2 shows the evaluation results.

In the evaluation, the transmittance and the total reflectance are
It was measured with an Olympus spectroscopic spectrophotometer (OSP-CB1, -CB2).

The resolution is 128, 80, 40, as the photomask 13 in the photolithography process.
Exposure was performed using a stripe having a width of 20, 8 or 5 μm and a mosaic arrangement, and the obtained pattern was observed with a microscope to evaluate the smallest width of the stripe widths that gave a sharp pattern. Value.

The tackiness of the coating film after photocuring is 25 ° C.
It was touched with a finger and evaluated in five levels according to the following criteria. A: I don't feel any tack. B ... Slightly tacky, but no finger marks were left on the coating film. C: A slight finger mark remains on the coating film. D: Fingerprints are clearly left on the coating film. E: The coating composition adheres to the finger.

The contrast is BM manufactured by Topcon Corp.
-7 Turn the voltage on and off at the liquid crystal panel using a luminance meter
The luminance ratio when FF was performed was measured.

Example 2 Using the compositions shown in Table 1,
A light-shielding thin film was formed and evaluated in the same manner as in Example 1.
Table 2 shows the evaluation results.

Example 3 Using the compositions shown in Table 1,
A light-shielding thin film was formed and evaluated in the same manner as in Example 1.
Table 2 shows the evaluation results.

Example 4 Using the compositions shown in Table 1,
A light-shielding thin film was formed and evaluated in the same manner as in Example 1.
Table 2 shows the evaluation results.

Example 5 Using the composition shown in Table 1,
A light-shielding thin film was formed and evaluated in the same manner as in Example 1.
Table 2 shows the evaluation results.

(Comparative Example 1) Using the compositions shown in Table 1,
A light-shielding thin film was formed and evaluated in the same manner as in Example 1.
Table 2 shows the evaluation results.

Comparative Example 2 Using the composition shown in Table 1,
A light-shielding thin film was formed and evaluated in the same manner as in Example 1.
Table 2 shows the evaluation results.

(Comparative Example 3) Using the compositions shown in Table 1,
A light-shielding thin film was formed and evaluated in the same manner as in Example 1.
Table 2 shows the evaluation results.

Comparative Example 4 Using the compositions shown in Table 1,
A light-shielding thin film was formed and evaluated in the same manner as in Example 1.
Table 2 shows the evaluation results.

Comparative Example 5 Using the compositions shown in Table 1,
A light-shielding thin film was formed and evaluated in the same manner as in Example 1.
Table 2 shows the evaluation results.

(Comparative Example 6) Using the compositions shown in Table 1,
A light-shielding thin film was formed and evaluated in the same manner as in Example 1.
Table 2 shows the evaluation results. However, the firing was performed only at a temperature of 160 ° C. or higher for about 10 minutes or longer.

Comparative Example 7 A thin film of metal Cr was directly formed on a transparent substrate by a vapor deposition method.

Comparative Example 8 A thin film was obtained by printing and firing using an ink in which an appropriate amount of carbon black or the like was mixed with a thermosetting resin.

(Comparative Example 9) Using a spinner or a roll coater, the composition shown in Table 1 was uniformly applied to the entire surface of the transparent substrate 12 in a film thickness of about 2 μm to form a coating film of the light-shielding thin film composition. 1 was formed, and then patterned in the same manner as in Example 1 to obtain a thin film.

Comparative Example 10 An ITO film was formed on a transparent substrate by sputtering or vacuum deposition, and electroless plating was applied to the formed ITO film to obtain a thin film.

[0067]

[Table 1]

[0068]

[Table 2]

As can be seen from Table 2, the coating films of Examples 1 to 5 and Comparative Examples 1 and 3 had a transmittance in the ultraviolet region of 5% or more before firing. These coating films were reliably photo-cured during exposure and could be microfabricated with a resolution of 5 to 8 μm with high precision. On the other hand, Comparative Examples 2, 4 and 5
The coating film in No. 2 has a transmittance of 5 in the ultraviolet region before firing.
% Or less, the exposure was insufficient, and the whole or a part of the formed thin film 15 was peeled off, resulting in poor workability.

In Examples 1 to 5, the combined weight of the thermochromic compound and the colorant was 5% by weight or more based on the combined weight of the photosensitive resin solution and the sol-ized transparent liquid. The thin films of these examples had an optical density in the visible light region of 3.0 or more after firing, and had excellent light-shielding properties.
On the other hand, in Comparative Examples 1 and 3, the total weight of the thermochromic compound and the colorant was less than 5% with respect to the total weight of the photosensitive resin and the solized transparent liquid. The thin films of these comparative examples had an optical density in the visible light region of 1.0 or less after firing, and had poor light-shielding properties.

The total reflectance is 1.0 or less in Examples 1 to 5 and Comparative Examples 1 to 5 containing an inorganic substance, while 1.6% in Comparative Example 6 containing no inorganic substance. That was all.

If the combined weight of the thermochromic compound and the colorant exceeds 50% of the combined weight of the photosensitive resin solution and the solized transparent liquid, the adhesion to the substrate 12 becomes poor. And cause peeling. This is one of the causes of the peeling of the thin film in Comparative Example 2.

Regarding the contrast, Examples 1 to 5 and Comparative Examples 6, 8 and 9 have a contrast of 1/10.
It was 0 <. In Comparative Examples 1 to 4, development was not possible due to peeling on the entire surface. In Comparative Examples 5, 7 and 10, the contrast was 1/100>.

As described above, the light-shielding thin film compositions of Examples 1 to 5 were able to form a thin film having a good light-shielding property with a high processing accuracy by a simple process by the photolithography method. In addition, the tackiness and the contrast were perfectly formed.

[0075]

EFFECTS OF THE INVENTION According to the present invention, it is made of a porous inorganic material and has a total reflectance (perspective from the substrate surface) of 1.5%.
A light-shielding thin film composition capable of forming an excellent light-shielding thin film having an optical density of 3.0 or more and a light-shielding thin film using the composition are obtained. When a coating film is formed on a substrate using this composition and processed by a photolithography method, the transmittance of the coating film with respect to the wavelength of exposure becomes 5% or more,
The coating film can be reliably photocured during exposure. Therefore, the processing accuracy of the coating film is high, and the contrast of the obtained light-shielding thin film is further enhanced.

By using the light-shielding thin film composition of the present invention, a light-shielding thin film having good adhesion to the substrate can be obtained.

[Brief description of drawings]

FIG. 1A to FIG. 1C are diagrams showing steps of forming a light-shielding thin film by a photolithography method using the light-shielding thin film composition of the present invention.

[Explanation of symbols]

 1 Coating film of light-shielding thin film composition 12 Transparent substrate 13 Photomask 14 Ultraviolet light 15 Thin film for light shielding

Claims (6)

[Claims] 1. A sol-forming transparent liquid obtained by hydrolyzing at least one metal compound having an alkoxy or acyloxy group; a thermochromic compound; a black color when the thermochromic compound discolors by a color-reduction method. A light-shielding thin film composition, which comprises: a colorant that gives a complementary color so as to exhibit the following; and a photosensitive resin. 2. The light-shielding thin film composition according to claim 1, wherein the metal compound is represented by the following general formula: M (OR ¹ ) _m (OR ² ) _n X _p Y _q, where M is , Magnesium, calcium, titanium, hafnium, germanium, zirconium, yttrium, aluminum, indium, gallium, tin, and silicon; R ¹ and R ² are each independently a hydrogen atom, An alkyl group,
Or an acyl group; X and Y are each independently a hydrogen atom, a chlorine atom or a hydroxyl group; and
m, n, p and q are each an integer of 0 to 8,
+ N is greater than or equal to 1 and m + n + p + q is equal to the valence of M. 3. The light-shielding thin film composition according to claim 1, wherein the thermochromic compound discolors when heated to lose water of crystallization. 4. The thermochromic compound in an amount such that the light transmittance at the exposure wavelength is 5% or more in exposure when coating on a transparent substrate, drying, and processing by a photolithography method. The light-shielding thin film composition according to claim 1, which comprises: and a colorant. 5. The total weight of the thermochromic compound and the colorant is 5 to 50 parts by weight with respect to 100 parts by weight of a sol-like solution containing the photosensitive resin and the solized transparent liquid. The light-shielding thin film composition according to claim 4, which is in the range of. 6. A light-shielding thin film formed on at least a part of a transparent substrate, which is obtained by forming a thin film of the light-shielding thin film composition according to claim 1 on a transparent substrate and baking it. A light-shielding thin film having a total reflectance of 1.5% or less and an optical density of 3.0 or more in the perspective of the thin film portion from the substrate surface.