JPH07218715A - Black matrix substrate and color filter using the same - Google Patents

Abstract

PURPOSE:To provide a black matrix substrate having high display contract, high dimensional accuracy, excellent light shading characteristics, high transmitted light density and low reflectance characteristics, and to provide a color filter using the same. CONSTITUTION:The black matrix substrate 12 is constituted by providing a substrate 13 and black patterns 15 which are formed on the substrate 13 and in which at least metal sulfide particles are incorporated. The color filter is constituted by providing the substrate 12, the black patterns 15 which are formed on the substrate 12 and in which at least metal sulfide particles are incorporated, colored layers formed between the black patterns 15 and a transparent electrode provided so as to cover the black patterns 15 and the colored layers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a black matrix substrate and a color filter using the same, and in particular, it has a high display contrast, a high dimensional accuracy, and an excellent light shielding property, and has a high transmission optical density and a low reflectance. The present invention relates to a black matrix substrate having characteristics and a color filter using the same.

[0002]

2. Description of the Related Art In recent years, monochrome or color liquid crystal displays have been attracting attention as flat displays. For example, a color liquid crystal display has three pixel parts.
The primary colors (R, G, B) are set, and the color switching is performed by controlling the transmission of light of each of the three primary colors by electrical switching of the liquid crystal. The liquid crystal display uses color filters in both the active matrix system and the simple matrix system to control the three primary colors.

This color filter is constructed by forming each colored layer, a protective layer and a transparent electrode layer on a transparent substrate.
And in order to increase the coloring effect and display contrast,
A black pattern (black matrix) having a light-shielding property is formed at the boundary portion of each of the R, G, and B pixels of the colored layer. Further, in an active matrix type liquid crystal display, since a thin film transistor (TFT) is used as a switching element, it is necessary to suppress a light leak current due to external light. Therefore, the black matrix is required to have a high light-shielding property.

Conventionally, as a black matrix, a chrome thin film formed by vapor deposition, sputtering or the like is photo-etched to form a relief, a hydrophilic resin relief is dyed, and a relief is formed using a photosensitive solution in which a black pigment is dispersed. And those formed by electrodeposition of a black electrodeposition paint, those formed by printing, and the like.

[0005]

However, a chrome thin film photo-etched and relief-formed has a high dimensional accuracy because it uses a photo process, but it requires a vacuum film-forming step such as vapor deposition or sputtering, and the manufacturing process. The manufacturing cost is high due to the complicated process. In particular,
This chrome black matrix needs to suppress the light reflectance on the observer side in order to enhance the display contrast under strong external light, and also suppresses the light leakage current that causes malfunction of the thin film transistor. It is necessary to suppress the light reflectance on the cell side (Japanese Patent Application No. 5-7517).
No. 8, etc.), therefore, it is necessary to perform vapor deposition, sputtering, etc. of low-reflection chromium which further increases the manufacturing cost.

The method using a photosensitive resist in which a black dye or pigment is dispersed has a low manufacturing cost, but the photosensitive resist is black, so that the photoprocess is liable to be insufficient, and a black matrix having good dimensional accuracy is obtained. There is a problem that can not be obtained.

Further, the black matrix formation by the printing method can reduce the manufacturing cost, but there is a problem when high dimensional accuracy is required.

In order to solve such a problem, the present applicant has previously proposed a black matrix substrate for a color filter and a manufacturing method thereof (Japanese Patent Application No. 3-3).
No. 25821). However, this black matrix also has a higher light reflectance on the observer side as compared with a black matrix using low reflection chromium in terms of optical characteristics, and further, a reduction in reflectance is required to obtain sufficient display contrast. It was In addition, regarding the black matrix of low-reflection chrome having excellent display contrast, the main sensitivity wavelength (55
5 nm), the light reflectance is low, but the visible light wavelength has a short wavelength region (around 400 nm) and a long wavelength region (700 nm).
In the vicinity), since the light reflectance is high, there is a disadvantage that a reddish purple interference color is observed when viewed from the observer side, and it is required to eliminate this interference color.

Therefore, there is a strong demand for the development of a black matrix which satisfies the above-mentioned required characteristics and is inexpensive to manufacture.

The present invention has been made in view of the above circumstances, and an object thereof is to be used for a flat display such as a liquid crystal display, an imager such as a CCD, or a color filter such as a color sensor. It is an object of the present invention to provide a black matrix substrate having a low light reflectance over the entire area, high dimensional accuracy, excellent light-shielding properties, and low cost, and a color filter using the same.

[0011]

In order to achieve such an object, a black matrix substrate of the present invention comprises a substrate and a black pattern formed on the substrate and containing at least metal sulfide particles therein. It is configured to include.

Here, the metal sulfide particles have a particle size of 5 to 5.
It is preferable that the particles have a particle size distribution such that the particles in the range of 30 nm account for 80% or more of all the particles, and the projected area density of the particles in terms of 0.06 μm thickness is 50% or more.

The metal sulfide particles include nickel sulfide, cobalt sulfide, copper sulfide, silver sulfide, palladium sulfide,
It is preferably at least one selected from the group consisting of iron sulfide.

Further, the black pattern has a light transmittance of 1 in the visible light wavelength range of 400 to 700 nm.
% Or less, the light reflectance on the observer side is 10% or less, the light reflectance on the liquid crystal cell side is 15% or less, and the light reflectance on the observer side is 7% or less at a wavelength of 555 nm. It is preferable to have optical characteristics such that the difference between the minimum value and the maximum value of the light reflectance in the visible light wavelength range of 400 to 700 nm is within 4%.

Further, the color filter of the present invention comprises the substrate, the black pattern formed on the substrate and containing at least metal sulfide particles therein, the colored layer formed between the black patterns, and the black layer. The transparent electrode is provided so as to cover the pattern and the colored layer.

[0016]

The metal sulfide particles are uniformly dispersed and deposited in the resin relief formed in advance on the substrate to form a black pattern, which absorbs the electromagnetic field energy in the visible light wavelength range. It is considered that the transmission optical density increases and the light transmittance decreases. In particular, the metal sulfide particles have a particle size distribution such that particles in the particle size range of 5 to 30 nm account for 80% or more of the total particles, and the projected area density of the particles is 50% or more. The black pattern has a light transmittance of 1% or less in the visible light wavelength region (400 to 700 nm) and a light reflectance of 1 on the observer side.
The light reflectance on the liquid crystal cell side is 0% or less, and the light reflectance on the observer side is 15% or less.
7% or less in the visible light wavelength region 4
The optical characteristics are such that the difference between the minimum value and the maximum value of the light reflectance in the range of 00 to 700 nm is within 4%, and as a result, even a thin film has excellent light-shielding properties and the light reflectance from the observer side. And a black matrix substrate with low interference color is observed. Further, since the resin relief is used, it is easy to form a pattern of the black matrix, and if a photosensitive resin or an electron beam resist is used, for example, the dimensional accuracy is high.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an example of an active matrix type liquid crystal display (LCD) using a black matrix substrate manufactured according to the present invention, and FIG. 2 is a schematic sectional view of the same. 1 and 2, the LCD 1 has a color filter 10 and a transparent glass substrate 20 which are opposed to each other with a sealing material 30 in between, and a thickness of about 5 to 1 made of twisted nematic (TN) liquid crystal between them.
A liquid crystal layer 40 having a thickness of about 0 μm is formed, and polarizing plates 50, 5 are provided outside the color filter 10 and the transparent glass substrate 20.
1 is provided and configured.

FIG. 3 is an enlarged partial sectional view of the color filter 10. In FIG. 3, the color filter 10 includes a black pattern (black matrix) 15 on a transparent substrate 13.
And the black matrix 15 of the black matrix substrate 12
The colored layer 16 formed between them, and the protective layer 18 provided so as to cover the black matrix 15 and the colored layer 16.
And a transparent electrode 19. The color filter 10 is arranged such that the transparent electrode 19 is located on the liquid crystal layer 40 side. The colored layer 16 is the red pattern 16
It is composed of R, green pattern 16G, and blue pattern 16B, and the array of each colored pattern is a mosaic array as shown in FIG. The arrangement of the coloring pattern is not limited to this, and may be a triangular arrangement, a stripe arrangement, or the like.

Display electrodes 22 are provided on the transparent glass substrate 20 so as to correspond to the respective colored patterns 16R, 16G and 16B, and each display electrode 22 has a thin film transistor (TFT) 24. Further, a scanning line (gate electrode busbar) 26a and a data line 26b are arranged between the respective display electrodes 22 so as to correspond to the black matrix 15.

In the LCD 1 as described above, each of the colored patterns 16R, 16G and 16B constitutes a pixel, and the display electrode corresponding to each pixel is turned on and off while the illumination light is emitted from the polarizing plate 51 side. The layer 40 operates as a shutter, and light is transmitted through each pixel of the colored patterns 16R, 16G, and 16B to perform color display.

In the present invention, as shown in FIG. 5, the black matrix substrate 12 constituting such a color filter 10 is formed on the substrate 13 and at least the metal sulfide particles inside. And a black pattern (black matrix) 15 contained therein.

As the substrate 13, a transparent substrate or a substrate having a reflecting portion is used. As the transparent substrate, a rigid material having no flexibility such as quartz glass, Pyrex glass, and a synthetic quartz plate, or a flexible material having flexibility such as a transparent resin film and an optical resin plate can be used. Among them, especially Corning 7059
Glass is a material with a small coefficient of thermal expansion, has excellent dimensional stability and workability in high-temperature heat treatment, and is a non-alkali glass that does not contain an alkaline component in the glass, so it is a color filter for LCDs using the active matrix method. Suitable for Further, for applications such as reflection projection type, a metal reflective film may be formed on one side of the transparent substrate, or a metal reflective film may be used for a display electrode of a thin film transistor or an active matrix on a silicone substrate. Good. When a substrate having a reflection portion is used, it becomes a black matrix substrate for a reflection type color filter, and is suitable for a reflection projection type, guest host or scattering type display mode.

The black pattern 15 is made of a resin (resin pattern) formed in a predetermined pattern and containing metal sulfide particles. In the present invention, the method of forming such a black pattern 15 is not particularly limited. For example, by preliminarily containing metal particles in the resin pattern and contacting it with an aqueous solution containing sulfide ions, or by leaving it in an atmosphere containing the sulfide ions, the metal particles in the resin pattern can be removed. It can be formed by using metal sulfide particles, but needless to say, it is not limited to these methods.

The metal sulfide particles contained in the black pattern 15 have a particle size in the range of 5 to 30 nm of 80.
% Particle size distribution, preferably between 7 and 15
Particles having a particle size distribution in which the particles in the range of nm are 80% or more of all particles, particularly while keeping the light reflectance low,
It is suitable for lowering the light transmittance. When the number of particles that do not have such a particle size distribution and exceed 30 nm is increased,
Since the characteristic distribution (numerical variation) of the light reflectance on the observer side becomes large, there is a region where the light reflectance exceeds 10%, which causes a disadvantage that a high-quality black matrix cannot be obtained. On the other hand, if there are many particles having a particle size of less than 5 nm, the disadvantage that the light transmittance of 1% or less, which is the optical characteristic required for the black matrix, cannot be obtained. The particle size referred to in the present invention is a value obtained by statistically processing, for example, 100 sample sizes measured from a TEM cross-sectional photograph of a black matrix section.

Further, the metal sulfide particles contained in the black pattern 15 preferably have a projected area density in terms of 0.06 μm thickness of 50% or more, more preferably 70% or more. If the projected area density of the particles converted to a thickness of 0.06 μm is less than 50%, optical characteristics with a light transmittance of 1% or less cannot be obtained even if the particle size is within the above-specified range.

The light transmittance is further related to the film thickness of the black pattern, and the thickness is set so that the above light transmittance is 1% or less. In addition, 0.06 of the metal sulfide particles
The projected area density in terms of μm thickness is as shown in FIG. 7 using a black pattern 15 in the film thickness direction using a microtome.
It slices with a width of 0.06 μm (FIG. 7A), and this slice piece 15a is obtained by observing it with a transmission electron microscope from the slice plane direction (FIG. 7B). As an example of a specific measuring method, the thickness of the slice was measured by a multi-differential interference microscope or the like, and a thickness close to 0.06 μm was selected and used. Note that it is difficult to slice with a thickness of 0.06 μm, and the thickness sliced with a thickness close to that is assumed to be t (nm), and at this time, a measured value of projection density d (%) is obtained. If the projected area density D is 0.06 μm,
Conversion to (%) was calculated by the following formula.

[0028]

[Equation 1] In the production of the black matrix substrate, the particle size of the metal sulfide particles is, for example, the plating time, the temperature of the plating solution, the pH of the plating solution, the agitation of the object to be plated (resin relief containing the catalyst nuclei), and the addition of the catalyst nuclei. It may vary depending on factors such as the concentration of the activation treatment liquid in the step, the treatment time, the concentration of the aqueous solution containing sulfide ions in the sulfurization reaction treatment step, the treatment time and the like.

In the present invention, as the metal sulfide particles, at least one selected from the group consisting of nickel sulfide, cobalt sulfide, copper sulfide, silver sulfide, palladium sulfide and iron sulfide is preferably used.

Such a black pattern 15 preferably has a light transmittance of 1% or less, more preferably 0.5% or less in the visible light wavelength range of 400 to 700 nm. It is also preferable that the light reflectance on the observer side is 10% or less, more preferably 5% or less, and the light reflectance on the liquid crystal cell side is 15% or less, more preferably 8% or less. Further, regarding the light reflectance of the observer side,
The light reflectance at a wavelength of 555 nm is 7% or less, more preferably 4% or less, and the visible light wavelength range is 400 to 70.
The difference between the minimum value and the maximum value in the range of 0 nm is within 4%,
More preferably, it has an optical property of being within 2%.

An example of the method for manufacturing the black matrix substrate 12 of the present invention will be described with reference to FIGS.

In FIG. 4, a transparent substrate 13 is first coated with a photosensitive resist containing a hydrophilic resin to a thickness of 0.1.
The photosensitive resist layer 3 having a thickness of about 5.0 μm, preferably about 0.1 to 2 μm is formed (FIG. 4A). Next, the photosensitive resist layer 3 is exposed through the photomask 9 for the black matrix (FIG. 4 (B)). Then, the exposed photosensitive resist layer 3 is developed to form a relief (resin pattern) 4 having a pattern for a black matrix (FIG. 4C). Next, heat treatment (8
After being subjected to 0 to 200 ° C. for 5 to 30 minutes), it is immersed in an aqueous solution of a metal compound serving as a catalyst for electroless plating, washed with water and dried to obtain a catalyst-containing relief (catalyst-containing resin pattern) 5 (see FIG. 4 ( D)). The heat treatment may be performed after the catalyst-containing relief is formed. Then, the catalyst-containing relief 5 on the transparent substrate 13 is brought into contact with the electroless plating solution to deposit metal particles in the relief to form a black relief 14 (FIG. 4 (E)). Further, the black relief 14 is dipped in an aqueous solution containing sulfide ions to form a black matrix 15 (FIG. 4 (F)).

Then, the black matrix is subjected to a film hardening treatment by heating or coating with a film hardening agent to form a black matrix substrate 12 (FIG. 5).

Another example of the method for manufacturing the black matrix substrate 12 will be described with reference to FIG.

First, a transparent substrate 13 is coated with a photosensitive resist containing a hydrophilic resin and an aqueous solution of a metal compound serving as a catalyst for electroless plating to a thickness of 0.1 to 5.0 μm, preferably 0.1 to 5.0 μm. A photosensitive resist layer 6 having a thickness of about 2 μm is formed (FIG. 6A). Next, the photosensitive resist layer 6 is exposed through the photomask 9 for black matrix (FIG. 6 (B)). Then, the photosensitive resist layer 7 after exposure is developed and dried, and then heat-treated (80 to 200 ° C., 5
~ 30 minutes) to form a catalyst-containing relief 7 having a relief for the black matrix (Fig. 6).
(C)). Next, the catalyst-containing relief 7 on the transparent substrate 13
Is brought into contact with the electroless plating solution to form the black relief 14 (FIG. 6D). Further, the black relief 14 is dipped in an aqueous solution containing sulfide ions to form a black matrix 15 (FIG. 6 (E)).

Then, in the same manner as in the case of the first manufacturing method example, the black matrix is subjected to a film hardening treatment by heating or coating with a film hardening agent to form a black matrix substrate 12 (FIG. 5).

A common characteristic of the above-mentioned production examples of the black matrix substrate is that metal particles are deposited by an electroless plating method in a resin relief containing a catalyst nucleus component having a function of initiating an electroless plating reaction. Further, the metal particles in the resin relief are brought into contact with an aqueous solution containing sulfide ions to promote a sulfide formation reaction (hereinafter referred to as a sulfurization reaction), and the metal sulfide particles are converted into a black matrix (light-shielding layer). ) Is uniformly dispersed and formed.

Therefore, as shown in FIG. 5, the black matrix substrate 12 obtained by the above-described manufacturing example is formed on the substrate 13 and contains at least the metal sulfide particles, and in some cases, the metal sulfide particles. A black matrix (black pattern) 15 having a predetermined relief shape containing a reducible metal salt of an electroless plating solution and a reducing agent is provided.

The resin used for the resin relief is
A resin that can be formed by a printing method or a photolithography method can be applied. As the resin used in the printing method,
For example, in the case of intaglio offset printing, various known gravure inks can be used. Examples of the resin used in the photolithography method include a photosensitive resist containing the hydrophilic resin, and examples thereof include gelatin and gelatin.
Natural proteins such as casein, glue, ovalbumin, carboxymethyl cellulose, polyvinyl alcohol, polyacrylic acid, polyacrylamide, polyvinylpyrrolidone, polyethylene oxide, maleic anhydride copolymer, and carboxylic acid modified products or sulfonic acids of the above resins. For one kind or a mixture of plural kinds of hydrophilic resins such as modified products, for example, a diazo resin which is a reaction product of a diazo group-containing diazo group compound and paraformaldehyde, an azide compound having an azide group,
Photosensitivity was imparted by adding a cinnamic acid condensation resin obtained by condensing cinnamic acid to polyvinyl alcohol, a resin using a stilbazolium salt, or a resin having a photocurable photosensitive group such as ammonium dichromate. Can be mentioned. Needless to say, the photosensitive group is not limited to the above-mentioned photocurable photosensitive group. As described above, since the photosensitive resist contains the hydrophilic resin, the electroless plating solution is contained in the catalyst-containing relief 5 when the catalyst-containing relief 5 comes into contact with the electroless plating solution as described above. It becomes easy to uniformly permeate, and metal particles can be uniformly deposited and grown in the relief containing the catalyst.

The metal compound serving as a catalyst for electroless plating is
For example, chlorides such as nickel, cobalt, palladium, gold, silver, tin, zinc, platinum, iron and copper, water-soluble salts such as sulfates and nitrates, and complex compounds are used. In particular, in producing the black matrix substrate of the present invention, an activator solution for electroless plating, which is commercially available as an aqueous solution, can be used as it is or after diluted. When such a metal compound is contained in the photosensitive resist as described above, the amount of the metal compound is 0.01 to
It is preferable to contain about 5% by weight.

The electroless plating solution is, for example, a reducing agent such as hypophosphorous acid, sodium hypophosphite, sodium borohydride, N-dimethylamineborane, borazine derivative, hydrazine and formalin, and nickel, cobalt,
Water-soluble reducible heavy metal salts such as iron, copper, chromium, palladium, gold, platinum, tin and zinc, and basic compounds such as sodium hydroxide, potassium hydroxide and ammonia, inorganic acids,
PH adjusters such as organic acids and oxycarboxylic acids such as sodium citrate, ammonium citrate, glycolic acid,
Typical examples are boric acid, carbonic acid, organic acids, and inorganic acid alkali salts. In addition to complexing agents for the purpose of stabilizing heavy metal ions in aqueous solutions, buffer agents, reaction accelerators, stabilizers, surfactants, etc. The electroless plating solution having is used. The electroless plating solution as described above has a pH value of 6 to 6 for controlling the reaction rate.
9. The plating solution temperature is preferably 15 to 40 ° C.

Two or more types of electroless plating solutions may be used in combination. For example, first, an electroless plating solution containing a boron-based reducing agent such as sodium borohydride that easily forms a catalytic nucleus of a plating reaction is used, and then a hypophosphorous acid-based reducing agent with a high metal deposition rate is used. An electrolytic plating solution can also be used.

Among the above-mentioned various reducing agents, particularly the boron-based reducing agent is used at room temperature (15 to 40 ° C.) for both the metal compound which becomes the catalyst nucleus of the electroless plating and the reducible metal salt. ) It has an excellent ability to be reduced and can be used.

An aqueous solution containing the above sulfide ion is
Examples thereof include alkaline aqueous solutions such as potassium sulfide solution, sodium sulfide solution, ammonium sulfide solution, barium sulfide solution, and lithium sulfide solution. In addition,
Of course, this sulfide ion aqueous solution is not limited to the above-mentioned alkaline aqueous solution. However, in the case of an acidic aqueous solution, since hydrogen sulfide gas is generated and the concentration of sulfide ions in the solution tends to decrease with time, an alkaline aqueous solution is preferable in consideration of the lifetime of the aqueous sulfide ion solution. Regarding the liquid temperature of this aqueous solution, the rate of sulfidation reaction increases as the liquid temperature rises, but the amount of volatile hydrogen sulfide gas generated also increases. Is preferred. Further, the above sulfide ion aqueous solution preferably has a sulfur content of 0.5% or more in order to efficiently proceed with the sulfurization reaction.

In the color filter 10 of the present invention, the colored layer 16 including the red pattern 16R, the green pattern 16G and the blue pattern 16B and the common electrode 19 are formed between the black matrix 15 of the black matrix substrate 12 as described above. You can get it. The colored layer 16 composed of the red pattern 16R, the green pattern 16G, and the blue pattern 16B is formed by a photoresist dyeing method or a pigment dispersion method in which a photosensitive resin in which a pigment is dispersed in advance is applied and then relief-printed by a photolithography method, It can be performed according to various known methods such as a printing method such as offset and an electrodeposition method.

In the color filter 10 of the present invention, either the black pattern 15 or the colored layer 16 may be formed on the substrate 13 first. Therefore, the red pattern 16R, the green pattern 16G, and the blue pattern 1 are first formed on the substrate 13.
Needless to say, it may be obtained by forming the colored layer 16 of 6B having a predetermined pattern and then forming the black pattern (black matrix) 15 between the patterns of the colored layers 16.

Further, a protective layer 18 may be provided so as to cover the black matrix 15 and the colored layer 16 of the color filter 10 to smooth the surface of the color filter 10, improve reliability, and prevent contamination of the liquid crystal layer 40. For example, a transparent resin such as an acrylic resin, a urethane resin, a polyester resin, an epoxy resin, a polyimide resin, or the like, and particularly a heat or light curable transparent resin is preferably used. Alternatively, it can be formed using a transparent inorganic compound such as silicon dioxide. The thickness of the protective layer is preferably about 0.5 to 50 μm.

As the transparent common electrode 19, for example, an indium tin oxide (ITO) film can be used. IT
The O film can be formed by a known method such as a vapor deposition method or a sputtering method, and the thickness thereof is preferably about 0.02 to 0.2 μm.

Next, the present invention will be described in more detail with reference to examples. (Production of Sample 1 of the Present Invention) 7059 glass (thickness: 1.1 mm) manufactured by Corning Incorporated as a transparent substrate, and 10
A polyethylene terephthalate (PET) film (Lumirror made by Toray) having a thickness of 0 μm adhered to glass was used. A photosensitive resist having the following composition was applied on these substrates by spin coating, and then at 70 ° C. for 10 minutes.
After drying for 1 minute, the photosensitive resist layer (thickness 0.6μ
m) was formed. (Composition of photosensitive resist) -Polyvinyl alcohol 4.47% aqueous solution (Nippon Gosei Kagaku KK, Gohsenal T-330) 1000 parts by weight-Diazo resin 5% aqueous solution (Shinko Giken D-011) 57 parts by weight Next, the photosensitive resist layer was exposed through a photomask for black matrix (line width 20 μm). As a light source for exposure, an ultrahigh pressure mercury lamp of 2 kW was used and irradiation was performed for 10 seconds. After that, spray development is performed using water at room temperature and air drying is performed to obtain a line width 20 for a black matrix.
A μm resin relief was formed.

Next, this resin relief is treated at 100 ° C. for 30 minutes.
After heat treatment for 1 minute and allowing to cool, it was immersed in an aqueous palladium chloride solution having a concentration of 100 ppm (manufactured by Nippon Kanigen Co., Ltd., a 5-fold diluted solution of Red Schumer solution) for 2 minutes, washed with water and drained to obtain a catalyst-containing relief. .

Thereafter, this transparent substrate was placed in an electroless N 2 at 20 ° C.
It was dipped in an iB plating solution (Top Chemialoy B-1 manufactured by Okuno Chemical Industries Co., Ltd.) for 3 minutes, washed with water and dried to form a black relief.

After that, the black relief is removed at 20 ° C.
Was immersed in an aqueous solution of ammonium sulfide (a colorless aqueous solution manufactured by Junsei Chemical Co., Ltd.) for 5 minutes, washed with water and dried, and then heat-treated at 200 ° C. for 1 hour to obtain a black matrix substrate. (Production of Inventive Sample 2) Inventive Sample 2 was produced in the same manner as Inventive Sample 1 except that the plating time of Inventive Sample 1 was changed from 3 minutes to 2 minutes. (Preparation of Inventive Sample 3) The concentration of the aqueous palladium chloride solution of Inventive Sample 1 is 100 ppm to 10 ppm.
Sample 3 of the present invention was prepared in the same manner as Sample 1 of the present invention, except that the plating time was changed from 3 minutes to 6 minutes. (Production of Comparative Sample 1) Comparative Sample 1 was prepared in the same manner as Sample 1 of the present invention, except that the step of sulfiding the sample 1 of the present invention with the aqueous ammonium sulfide solution was omitted.
Was produced. (Preparation of Comparative Sample 2) Comparative Sample 2 was prepared in the same manner as Sample 1 of the present invention except that the plating time of Sample 1 of the present invention was changed from 3 minutes to 1 minute. (Preparation of Comparative Sample 3) Comparative Sample 3 was prepared in the same manner as Sample 1 of the present invention except that the plating time of Sample 1 of the present invention was changed from 3 minutes to 5 minutes. (Preparation of Comparative Sample 4) Comparative Sample 4 was prepared in the same manner as Sample 3 of the present invention except that the plating time of Sample 3 of the present invention was changed from 6 minutes to 3 minutes. (Preparation of Comparative Sample 5) A chromium oxide film (film thickness 0.025 μm) was formed on the transparent substrate used in the present invention sample 1 by a sputtering method, and a chromium film (film thickness 0.107 μm) was further formed thereon. ) Was formed into a film to form a two-layer film substrate. (Chromium film sputtering conditions) -Substrate temperature: 150 ° C-Sputtering power: 2 kW-Ar gas flow rate: 30 sccm-Ar gas pressure: 0.3 Pa-Sputtering rate: 0.05 μm / min Next, on this double-layer film substrate Photosensitive resist (OFPR-800, manufactured by Tokyo Ohka Kogyo Co., Ltd.) by spin coating
10 cP) and then dried at 90 ° C. for 30 minutes to form a photosensitive resist layer (thickness 0.9 μm).

Next, the photosensitive resist layer was exposed through a photomask for black matrix (line width 20 μm). As a light source for exposure, an ultrahigh pressure mercury lamp of 2 kW was used and irradiation was performed for 10 seconds. Then, dip development was performed using a developing solution (NMD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd.) and air-dried to form a resin relief having a line width of 20 μm for producing a black matrix.

Next, this resin relief is treated at 120 ° C. for 30 minutes.
After heat treatment for 1 minute and allowing to cool, it was immersed in a chromium etching solution (MR-ES, manufactured by The Inktech Co., Ltd.) for 2 minutes to form a metal relief. After that, the resin relief on the metal relief was removed by a remover to obtain a black matrix substrate.

Among the above samples, the present invention sample 1 and the comparative sample 1 were used to identify the metal sulfide particles. The identification was performed by the following method. First, before and after the treatment step of the sulfurization reaction of the black matrix, as a result of performing a particle size change by cross-sectional TEM observation and elemental analysis (mapping by point analysis) by energy dispersive X-ray microanalysis (EDX), the sulfurization reaction treatment step After that, an increase in particle size and the detection of elemental sulfur were observed (see FIGS. 8 to 11; Sample 1 of the present invention (FIGS. 8 and 1).
0) and comparative sample 1 (FIGS. 9 and 11)). In addition, the resin relief only is subjected to a sulfurization reaction treatment and ED
When elemental analysis by X was carried out, no elemental sulfur was detected in this case. From the above results, it was found that the metal particles in the resin relief generate metal sulfides on the surface of the particles by the sulfurization reaction treatment and form metal sulfide particles having a larger particle size than the metal particles before the treatment. did.

Next, the particle size and projected area density of the nickel sulfide particles in the black matrix of the above eight samples (inventive samples 1 to 3 and comparative samples 1 to 5) were measured by a transmission electron microscope (manufactured by Hitachi Ltd.). ,
H-8100).

Regarding the light transmittance (T) and light reflectance (R) of the black matrix, a microscopic spectrophotometer (AH2-SRK / STK, Olympus Optics Co., Ltd.) was used to convert the light into light that is almost vertically incident on the substrate. On the other hand, the transmitted light and the specularly reflected light were measured. In addition, the light transmittance of the black matrix is determined by the above-mentioned device by using a transparent substrate as a reference (100% transmittance) and a background (0% transmittance) when light is completely cut off as a visible light wavelength. The highest transmittance T (%) measured in the range of 400 to 700 nm was evaluated. Also,
The light reflectance was measured on the basis of an aluminum vapor-deposited plate as a reference and the case where there was no reflective material at all as a background. Particularly, regarding the light reflectance, the light reflectance when the light is irradiated from the substrate side of the black matrix 15 (reflectance R _O on the observer side) and the light reflectance when the light is irradiated from the film surface side (the liquid crystal cell side Two types of reflectance R _L ) were evaluated.

The measurement results are shown in Table 1. Since the measured value of the light transmittance of 0.1% or less is less than the measurement limit value of the device and it is considered that there is no significant difference, the light transmittance T ≦ 0.1
Expressed as%.

[0059]

[Table 1] In addition, "maximum value-minimum value" in the table means a wavelength of 400 to 70.
The difference between the maximum value and the minimum value of the light reflectance in the range of 0 nm.

As is clear from the results of Table 1, in the samples 1 to 3 of the present invention, the particle size of nickel sulfide particles is 5 to 30 n.
Since the particles in the range of m have a particle size distribution such that they are 80% or more of all particles, and the projected area density of the particles is 50% or more, the light reflectance on the observer side is remarkably reduced, and black Light transmittance required for the light-shielding layer of the matrix (1%
The following) were also sufficiently obtained and were extremely excellent as a black matrix substrate.

Particularly, the sample 1 of the present invention has a light reflectance of 1.6 at the wavelength of 555 nm on the observer side.
The difference between the minimum value and the maximum value in the wavelength range of 400 to 700 nm was 3%, which was favorable at 1.58%. Therefore, no interference color was visually observed.

On the other hand, in Comparative Samples 1, 2, and 4, since the projected area density of nickel particles is less than 50%, the light reflectance is low, but the light transmittance is black matrix light shielding. It was not sufficient as a black matrix substrate because it did not satisfy the numerical value required to obtain the original function of the property. Further, in comparative sample 3, the projected area density of particles is 89.3%.
And within the definition of the present invention, the particle size is 5 to 30 n
Since the particles in the range of m are less than 80% of all particles, there are many large particles having a particle diameter of more than 30 nm, and as a result, the light reflectance on the observer side is 8.58 at a wavelength of 555 nm. %, Wavelength 400 to 700n
The difference between the minimum value and the maximum value of the light reflectance in the range of m was 4.27%, which was insufficient for the low reflection black matrix substrate in which no interference color was observed, which is the object of the present invention.

Further, with respect to Comparative Sample 5, which is a current low-reflection black matrix composed of a low-reflection chrome film, the film structure cannot be compared with the sample of the present invention, but the optical characteristics are compared. Is 0.1% or less, and the light reflectance on the observer side at a wavelength of 555 nm is 2.47%, which is extremely good, but the light reflectance on the observer side is in the visible light wavelength range of 400 to 700 n.
The difference between the minimum value and the maximum value of the light reflectance in the range of m is 8.29%, and the light reflectance on the liquid crystal cell side is 1
Since it has an optical characteristic of more than 5%, it is insufficient as a low reflection black matrix substrate which suppresses the light leak current which causes the malfunction of the TFT and does not show the interference color.

Next, a black pattern was formed on the glass substrate under the same conditions as in Sample 1 of the present invention. Using this black matrix substrate, the color filter of the present invention was produced in the following manner.

That is, using a plate having a stripe-shaped intaglio plate having a plate depth of 6 μm and a width of 110 μm, and a silicone blanket, by the intaglio offset printing method, the following ink composition S-1 was formed between the black matrices on the black matrix substrate. S-2 and S-3 were printed in this order to form blue, green and red stripe patterns having a width of 110 μm, respectively. Then, the ink composition was thermally cured by heating the substrate at 200 ° C. for 30 minutes to obtain a colored layer having a thickness of 2 to 3 μm. (Composition of varnish) -Polyester acrylate resin (Toagosei Kagaku Kogyo Co., Ltd., Aronix M-7100) 70 parts by weight-Diallyl phthalate prepolymer 30 parts by weight (Composition of ink composition (S-1))-Varnish 100 Parts by weight ・ Pigment (Rionol Blue ES) (Toyo Ink Manufacturing Co., Ltd., CI Pigment Blue 15: 6) 15.5 parts by weight ・ Pigment (Rionogen Violet RL) (Toyo Ink Manufacturing Co., Ltd., CI Pigment Violet 23) 4 parts by weight (composition of ink composition (S-2)) 100 parts by weight of varnish ・ Pigment (Rionol Green 2YS) 22 parts by weight of CI Pigment Green 36 (Toyo Ink Mfg. Co., Ltd.) ・ Pigment (Seika First Yellow) 2700) (CIPigment Yellow 83, manufactured by Dainichiseika Co., Ltd.) 7.5 parts by weight (composition of ink composition (S-3)) 100 parts by weight of varnish Material (Chromophtal Red A3B) (Ciba Pigment Co., CIPigment Red 177) 32 parts by weight Pigment (Seika First Yellow 2700) (Dainichi Seika Chemicals Co., Ltd., CI Pigment Yellow 83) 8 parts by weight As described above, a protective layer and a transparent electrode were formed to obtain a color filter. That is, the formation of the protective layer was performed by applying a coating solution having the composition shown below by spin coating (rotation speed 1500
r. p. m. ) Was applied onto the above colored layer (film thickness 2.0 μm). (Composition of coating liquid for forming protective layer) -Photo-curable acrylate oligomer (o-cresol novolac epoxy acrylate (molecular weight 1500 to 2000)) 35 parts by weight-Cresol novolac type epoxy resin 15 parts by weight-Polyfunctional polymerizable monomer (Dipentaerythritol hexaacrylate (DPHA manufactured by Nippon Kayaku Co., Ltd.)) 50 parts by weight Polymerization initiator (Ciba Geigy, Irgacure) 2 parts by weight Epoxy curing agent (General Electric, UVB1014) ) 2 parts by weight-Ethyl cellosolve acetate 200 parts by weight And an exposure amount of 150 mJ was applied to this coating film by using a proximity exposure device manufactured by Dainippon Screen Co., Ltd.
The whole surface was exposed at / cm ² . Then, the substrate is immersed in 1,1,2,2-tetrachloroethane at room temperature for 1 minute,
Only the uncured portion of the coating film was removed to form a protective film.

Further, a 0.4 μm thick indium tin oxide (ITO) film was formed on the protective film by a sputtering method.
A film was formed to form a transparent electrode, and a color filter was obtained.

Using the color filter thus manufactured and a TFT substrate formed by a known method, LC
A D panel was produced.

Amorphous silicon was used for the semiconductor layer of the TFT substrate, and the polarizing plate of the LCD was attached so as to be normally white.

In order to evaluate the characteristics of this LCD, the relationship between the gate voltage and the light transmittance of the LCD was measured.

As a result, in the LCD using the color filter according to the present invention, the LCD using the color filter according to the conventional method using chromium as the black matrix layer.
It was found that the gate-off voltage can be reduced by 2 V as compared with

This is because when the color filter of the conventional method is used, a part of the light of the backlight of the LCD is reflected on the surface of the black matrix layer because the reflectance of the black matrix layer of the color filter is high. The incident light is incident on the TFT, which causes a light leakage current of the TFT. On the other hand, in the color filter using the black matrix substrate of the present invention, the reflectance of the surface of the black matrix layer is low. It is presumed that the amount of light irradiation to the TFT is reduced, and as a result, the light leakage current of the TFT is reduced and the gate-off voltage is improved.

From this result, an LCD using a color filter using the black matrix substrate according to the present invention
In, the driving voltage of the LCD can be reduced, and the effect of reducing the power consumption was confirmed. This has a great effect on extending the continuous use time when the dry battery is driven.

Further, in order to evaluate another effect of the color filter according to the present invention, the contrast ratio of the LCD was measured.

In contrast ratio measurement in a bright place, a contrast ratio 2.8 times that of the conventional color filter could be obtained.

It is presumed that this is because the influence of outside light was reduced by lowering the reflectance of the black matrix layer of the color filter.

Even when the contrast ratio was measured in a dark place, when the color filter according to the present invention was used, a contrast ratio 1.8 times that of the conventional method could be obtained.

This is because when the color filter using the black matrix substrate of the present invention is used, the light leakage current of the TFT is reduced as described above, and as a result, the leakage light at the time of black display is reduced. It is presumed that it was improved.

As described above, it was found that the color filter according to the present invention is effective in reducing the power consumption of the LCD and improving the contrast ratio.

[0079]

As described in detail above, according to the present invention,
The metal sulfide particles are uniformly dispersed and deposited in the resin relief formed in advance on the substrate to form a black pattern, whereby the electromagnetic wave energy is absorbed in the visible light wavelength region, thereby increasing the transmission optical density. , The light transmittance decreases. In particular, metal sulfide particles having a particle size of 5 to 3
The particle size distribution is such that particles in the range of 0 nm are 80% or more of all particles, and the projected area density of particles is 50% or more, whereby the visible light wavelength region (400 to 700 nm)
Transmittance is 1% or less, observer side reflectance is 10%
Hereinafter, the reflectance on the liquid crystal cell side is 15% or less, the reflectance on the observer side is 7% or less at a wavelength of 555 nm, and the minimum and maximum values in the visible light wavelength range of 400 to 700 nm. It is possible to obtain a black matrix having optical characteristics such that the difference between the two is within 4%.
When this is used for a liquid crystal display device, even a thin film has excellent light-shielding properties, the reflectance from the observer side is low, and interference colors are not recognized, so that the visibility can be improved. Further, in the active matrix system, the light reflectance on the liquid crystal cell side can be suppressed to a low level, so that stray light in the liquid crystal is reduced and TF
The light leak current that causes the malfunction can be suppressed, and the effects of reducing the power consumption of the LCD and improving the contrast ratio are also obtained. Also, since a resin relief is used, it is easy to form a black matrix pattern,
For example, if a photosensitive resin or an electron beam resist is used, there is an advantage that the dimensional accuracy is high.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of an active matrix liquid crystal display using a color filter manufactured according to the present invention.

FIG. 2 is a schematic sectional view of the liquid crystal display shown in FIG.

FIG. 3 is an enlarged partial sectional view of a color filter of the present invention used in the liquid crystal display shown in FIG.

FIG. 4 is a process chart for explaining an example of a method of manufacturing a black matrix substrate according to the present invention.

FIG. 5 is a schematic sectional view of a black matrix substrate of the present invention.

FIG. 6 is a process chart for explaining another example of a method for manufacturing a black matrix substrate according to the present invention.

FIG. 7 is a diagram schematically showing a method for measuring the projected areal density of particles. FIG. 7A is a diagram in which the peeled black matrix 15 is sliced in a width of 0.06 μm in the thickness direction, and FIG. 7B is a transmission electron microscope from a slice plane direction of the sliced piece 15 a. It is a figure to observe.

FIG. 8 is a drawing-substituting photograph showing a thin film cross section obtained by slicing the black matrix prepared as Sample 1 of the present invention in the thickness direction with a width of 0.06 μm, and observing the sliced piece with a transmission electron microscope from the slice plane direction. is there.

FIG. 9 is a drawing-substituting photograph showing a thin film cross section obtained by slicing a black matrix manufactured as Comparative Sample 1 in a thickness direction with a width of 0.06 μm and observing the sliced piece with a transmission electron microscope from the slice plane direction. .

FIG. 10 is a drawing-substitute photograph in which the photograph of FIG. 8 is further magnified 5 times.

FIG. 11 is a drawing-substitute photograph in which the photograph of FIG. 9 is further magnified 5 times.

FIG. 12 is a reflection spectral characteristic view from the observer side of the black matrix manufactured as Sample 1 of the present invention.

FIG. 13 is a reflection spectral characteristic view from the liquid crystal cell side of the black matrix produced as Sample 1 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display (LCD) 3 ... Photosensitive resist layer 4 ... Resin relief 5 ... Catalyst containing relief (catalyst containing resin pattern) 9 ... Photomask for black matrix 10 ... Color filter 12 ... Black matrix substrate 13 ... Substrate 14 ... Black relief 15 ... Black matrix (black pattern) 16 ... Colored layer 16R, 16G, 16B ... Colored pattern 18 ... Protective layer 19 ... Transparent electrode

Claims (5)

[Claims] 1. A black matrix substrate comprising a substrate and a black pattern formed on the substrate and containing at least metal sulfide particles therein. 2. The metal sulfide particles have a particle size of 5 to 30 n.
The particles having a particle size distribution such that the particles in the range of m are 80% or more of all particles, and the projected area density of the particles in terms of 0.06 μm thickness is 50% or more. The black matrix substrate described. 3. The metal sulfide particles are nickel sulfide,
The black matrix substrate according to claim 1 or 2, which is at least one selected from the group consisting of cobalt sulfide, copper sulfide, silver sulfide, palladium sulfide, and iron sulfide. 4. The black pattern has a visible light wavelength region 4
In the range of 00 to 700 nm, the light transmittance is 1% or less, the light reflectance on the observer side is 10% or less, and the light reflectance on the liquid crystal cell side is 15% or less. The optical characteristics are such that the light reflectance at the wavelength of 555 nm is 7% or less, and the difference between the minimum value and the maximum value of the light reflectance in the visible light wavelength range of 400 to 700 nm is within 4%. , Claim 1
4. The black matrix substrate according to any one of 1 to 3. 5. A substrate, a black pattern formed on the substrate and containing at least a metal sulfide particle therein, a colored layer formed between the black patterns, and the black pattern and the colored layer are covered. A color filter using the black matrix substrate according to any one of claims 1 to 3, comprising a transparent electrode provided.