JP2001174620A - Color filter and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color filter without defects such as pinholes on an overcoat layer, releasing, a change of color in a pigment layer or the like throughout a series of panel manufacturing process comprising high temperature baking, wiring of transparent electrodes or the like, with a smooth upper layer, a high adhesion property and excellent reliability in the color filter with the pigment layer regularly arranged between a substrate and the overcoat layer formed on the substrate and its manufacturing method. SOLUTION: In the color filter with the pigment layer and a light shielding layer regularly arranged between the substrate and the overcoat layer formed on the substrate, the pigment layer is composed of inorganic pigments, the light shielding layer is composed of the inorganic pigments and a low-melting glass and the overcoat layer is composed of the low-melting glass. The color filter is characterized by comprising the low-melting glass containing 50-65 wt.% PbO and 25-35 wt.% SiO2 with respect to the light shielding layer and the overcoat layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for various display devices such as a plasma display, an electroluminescence display, a field emission display, and a liquid crystal display, and a solid-state imaging device.
The present invention relates to a color filter for color synthesis or color separation and a method for manufacturing the same.

[0002]

2. Description of the Related Art For example, a color liquid crystal display requires a color filter for performing color display, and a color filter manufactured by a known method such as a dyeing method or a pigment dispersion method is used. This is to color a resin layer using an organic dye or an organic pigment to form a color filter. In a plasma display, it has been proposed to use a color filter in order to improve contrast when displaying an image. Thus, in some display devices, a color filter is indispensable for improving color display and image quality.

[0003] In the case of a plasma display,
The fabrication process includes a process of firing at about 600 ° C. If a color filter for a liquid crystal display is used for a color filter for a plasma display, the organic dyes, organic pigments, and resin binders constituting the color filter may undergo a combustion or decomposition reaction in such a process, and the characteristics of the color filter may not be obtained. I will.

As a solution to this problem, it has been proposed to use a heat-resistant inorganic pigment formed on a substrate as a color filter. In this method, a paste obtained by mixing an inorganic pigment with an appropriate binder resin and a solvent is patterned on a predetermined substrate by a method such as screen printing, and thereafter, the binder resin and the solvent are removed by firing, and the inorganic pigment filter is removed. What you get. In this case, since the color filter is an inorganic pigment, it can withstand a high-temperature process involved in manufacturing a plasma display.

[0005]

When a color filter is used in a plasma display, an electroluminescence display, a field emission display, or the like, a transparent electrode is wired above or below the color filter from the panel structure. It is extremely important for the transparent electrode to prevent disconnection and pinholes. Therefore, the filter layer is required to have not only heat resistance but also chemical resistance, adhesion and surface smoothness in an electrode pattern wiring process.

[0006] The color filter manufactured by the conventional method has a pattern formed on a substrate at a predetermined position of a filter layer, so that surface irregularities occur.

In order to ensure the performance without causing defects or defects such as disconnection of the transparent electrode due to such a surface structure, it is necessary to form a glass overcoat layer or add a glass component to the filter layer itself. It is proposed to be introduced. However, simply applying the overcoat layer to the display area does not provide mechanical strength and peels off from the filter layer, and simply introducing a glass component into the filter layer results in insufficient smoothness with respect to the filter layer step. It did not meet the required performance. Furthermore, with respect to only the overcoat layer, problems such as generation of pinholes, reduction in spectral transmittance of a color filter due to low transmittance, and chemical resistance in an electrode wiring process could not be solved.

In particular, when the thickness of the filter layer is increased so as to absorb the bottom transmittance sufficiently for color separation, the thickness of each color is increased to 10 to 50 μm, the surface smoothness is deteriorated, and the binder is removed by firing. In this case, the adhesion cannot be maintained only by the adhesion between the pigments, and the entire overcoat layer is peeled off from the filter layer, resulting in a problem that the mechanical strength cannot be secured.

Further, if the thermal expansion coefficient of the substrate used does not match the thermal expansion coefficient of the overcoat layer, there have been problems such as warpage and distortion of the substrate and cracks in the filter layer and the overcoat layer themselves.

SUMMARY OF THE INVENTION The present invention has been made to solve such problems, and it is an object of the present invention to provide a color filter having a smooth upper surface, having no pinholes, being transparent and having high adhesion, and a method of manufacturing the same. And

[0011]

According to the present invention, a dye layer and a light-shielding layer are regularly arranged between a substrate and an overcoat layer formed on the substrate. In the arranged color filters, the dye layer is made of an inorganic pigment, the light-shielding layer is made of an inorganic pigment and a low-melting glass, and the overcoat layer is made of a low-melting glass. PbO50~65 wt% in the low-melting glass layer, SiO ₂
A color filter characterized by containing 25 to 35% by weight.

In the invention according to the second aspect, the ratio of the low melting point glass in the light shielding layer is 30 to 400 parts by weight based on 100 parts by weight of the inorganic pigment. This is a color filter.

According to a third aspect of the present invention, in the method for manufacturing a color filter according to the first or second aspect, after the light-shielding layer and the dye layer are patterned on the transparent substrate, baking is performed, and then the substrate is fired. After forming a pattern of an overcoat layer so as to cover the entire surface, it is baked again to form a light-shielding layer, a dye layer, and an overcoat layer on the substrate. .

According to a fourth aspect of the present invention, in the method for manufacturing a color filter according to the first or second aspect, after the light-shielding layer, the dye layer, and the overcoat layer are sequentially patterned on the transparent substrate, they are collectively formed. And baking to form a light-shielding layer, a dye layer, and an overcoat layer on the substrate.

According to the color filter of the present invention, since the low melting point glass is contained not only in the overcoat layer but also in the light shielding layer, the adhesion of the filter layer to the glass substrate is increased. Further, by defining PbO and SiO ₂ of the low-melting glass contained in the overcoat layer, generation of pinholes and reduction in spectral transmittance can be suppressed, and chemical resistance in the electrode wiring step can be improved.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. As shown in FIG. 1, the color filter of the present invention has a substrate 10
And a dye layer 11 and a light-shielding layer 12 which are patterned at predetermined positions and arranged regularly, and an overcoat layer 13 which covers them.

As the substrate, any substrate having high transparency and excellent properties such as heat resistance and weather resistance can be used. Examples of the substrate include soda lime glass, borosilicate glass, and aluminosilicate glass which are usually used for color filters. A heat-resistant non-alkali plate glass or the like can be used.

The light-shielding layer 12, which is regularly formed at a predetermined position on the substrate, comprises an inorganic pigment for shielding light and PbO-S
It is composed of low melting point glass having iO ₂ as a basic composition.

As the inorganic pigment, for example, Cu-Cr-M
n, Cu-Fe-Mn, Co-Fe-Cr-Mn, Co
-Ni-Fe-Mn, but the red pigment Fe_Two
O_Three, Green pigment TiO_Two—CoO—NiO—ZnO, C
oO-CrO-TiO_Two-Al _TwoO_Three, Blue pigment CoO
-Al_Two, CoO-CrO, CoO-Al_TwoO_ThreeEtc.
-Pigments can be appropriately mixed and used. Of inorganic pigments
The particle size is between 0.03 and 0.1 μm.

The low melting glass is composed of PbO
50-65 wt%, used those containing SiO ₂ 25 to 35 wt% as a basic configuration. PbO 50% by weight
Below this, the softening point of the glass increases and a high firing temperature step is required. For this reason, distortion or deformation occurs depending on the substrate to be used, and the selectable substrate is restricted, and the dye layer having low heat resistance causes discoloration.
On the other hand, if PbO is 65% by weight or more, vitrification becomes difficult, so that devitrification tends to occur. On the other hand, if the SiO ₂ content is 25% by weight or less, the strength and the acid resistance tend to decrease, and in particular, the chemical resistance tends to decrease and peeling tends to occur in the electrode wiring etching step. On the other hand, if the SiO ₂ content is 35% by weight or more, the softening point of the glass becomes high, and devitrification and pinholes tend to remain.

In addition to the basic components of PbO and SiO ₂ , BaO, ZnO, B ₂ O ₃ , Na ₂ O, K ₂ O or F
_With the composition to which ₂ is added, the softening point and the coefficient of thermal expansion of the glass frit formed by melting and pulverizing the low melting point glass can be appropriately used. The difference between the thermal expansion coefficient of the glass frit and that of the substrate is preferably within ± 5 × 10 ⁻⁷ / ° C.

The ratio of the low melting point glass in the light shielding layer is preferably in the range of 30 to 400 parts by weight based on the weight of the inorganic pigment. If the amount is less than 30 parts by weight, the adhesion of the light-shielding layer tends not to be obtained, and peeling will occur in a post-process such as baking for removing organic components or etching for electrode wiring. On the other hand, if the amount is more than 400 parts by weight, the hiding power is reduced, and a desired optical density cannot be obtained.

As the dye layer 11, those indicated by the inorganic pigments used for the light-shielding layer can be suitably used in accordance with the respective colors, and a plurality of kinds can be mixed to adjust the color.

In order to form a regular light-shielding layer such as a stripe or a matrix on a substrate, a light-shielding layer paste composed of an inorganic pigment, a low-melting glass frit having a particle diameter of 10 μm or less, a binder resin, and a solvent is used. , A printing method, a photolithography method, or the like. For the dye layer, a dye paste composed of only an inorganic pigment, a binder resin, and a solvent is used, and a pattern is repeatedly formed by the same method as that for the light-shielding layer according to the number of colors.

In the case of the printing method, there is a screen printing method in which a light-shielding layer paste obtained by kneading an inorganic pigment and a low-melting glass frit into an appropriate binder resin is pressed and applied through a screen mesh having a predetermined shape to form a pattern. Can be In addition, the printing can be performed by various printing methods such as a lithographic offset printing method.

In the photolithography method, an inorganic pigment and a low-melting glass frit are kneaded in an appropriate photosensitive resin, the obtained light-shielding layer paste is applied on a substrate, and the paste is exposed using a predetermined mask. Thereafter, patterning can be performed by developing.

In order to form an overcoat layer on a substrate on which a light-shielding layer and a dye layer are formed, screen printing is performed using an overcoat paste composed of a low-melting glass frit having a particle size of 10 μm or less, a binder resin, and a solvent. It can be applied by a method, dip coating or spin coating.

It is important that the binder resin used in the light-shielding layer, the dye layer and the overcoat layer has a composition capable of removing organic substances by firing. In particular, it is necessary to decompose in an atmosphere with a limited amount of oxygen introduced,
No carbonaceous matter should be left after firing. Accordingly, a part or all of the hydroxyl groups are etherified with a hydrocarbon residue having 1 to 3 carbon atoms, or an addition-polymerizable photopolymerizable composition containing at least one ethylenically unsaturated double bond ( An ethylenic compound), a sensitizer that absorbs ultraviolet light or visible light, and a photopolymerization initiator composed of a sensitizing dye are used.

Examples of the ethylenic compound include dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, and ethylene glycol di (meth) acrylate which are known as ultraviolet curable compounds containing an acryloyl group or a methacryloyl group. And (meth) acrylate-based ethylenic compounds such as tetrahydrofurfuryl (meth) acrylate. Also, N-vinylpyrrolidone can be used.

As the binder resin, alkyl acrylate, polyalkyl acrylate, or alkyl methacrylate, polyalkyl methacrylate, or various copolymer acrylics thereof are used for the purpose of increasing the crosslink density by photocuring and improving the pattern resolution. A system copolymer or the like can be appropriately selected and used.

An inert liquid organic solvent can be used as the solvent, and the boiling point is preferably in the range of 100 to 350 ° C. Thus, suitable solvents include methyl ethyl ketone, methyl isobutyl ketone, ketones such as cyclohexanone, terpenes such as α or β terpineol, or kerosene, dibutyl phthalate, butyl carbitol, butyl carbitol acetate, hexamethienene, glycol, and Mixtures with other solvents such as boiling alcohols and alcohol esters. These solvents are appropriately selected and used in order to obtain desired viscosity and volatility requirements for various coating methods.

The low melting point glass frit used for the light shielding layer paste and the overcoat paste preferably has a particle size of 10 μm or less. When the thickness is 10 μm or more, the pattern resolution tends to decrease in the light-shielding layer paste, and it is difficult to obtain surface smoothness even if softening is performed in the baking step in the overcoat paste, and pinholes and the like easily occur. That's why.

After the patterning of the light-shielding layer and the dye layer and the formation of the overcoat layer as described above, baking is performed to remove organic components and soften the low-melting glass frit. Alternatively, after patterning the light-shielding layer, the dye layer, and the overcoat layer, baking is performed to remove organic components and soften the low-melting glass frit.

[0034]

<Example 1> First, a low-melting glass frit was produced in the following procedure. PbO62 as glass material
Wt%, SiO ₂ 28 wt%, B ₂ O ₃ 5 wt%, Na ₂ O
Using a crucible in a ratio of 2.5% by weight and 2.5% by weight of F ₂ , melting was carried out at 1300 ° C. until bubbles disappeared. After the melting was completed, the mixture was put into pure water to obtain a glass powder. Further, a mill additive was added, mixed with water, and pulverized by a ball mill. Thus, it has a particle size distribution of 3 to 7 μm, a softening point of 560 ° C., and a thermal expansion coefficient of 61 × 10 ⁻⁷ / ° C.
Was prepared.

Next, 100 parts by weight of "TM Color # 3480" manufactured by Dainichi Seika as a black pigment and 100 parts by weight of the above-mentioned low melting point glass frit were used as a binder resin in 5 parts by weight of ethyl cellulose (manufactured by Kanto Kagaku) and α-solvent as a solvent. Terpineol (manufactured by Kanto Chemical Co.) was mixed with 40 parts by weight to prepare a light-shielding layer paste dispersed in a bead mill.

This light-shielding layer paste was printed using a screen stencil of polyester 300 mesh having stripe openings, and a line width of 150 μm and a pitch of 150 μm on a soda-lime glass substrate 10 (coefficient of thermal expansion: 75 × 10 ⁻⁷ / ° C.). 22
A light-shielding layer (black stripe) pattern 12 having a thickness of 0 μm and a thickness of 8 μm was formed by printing.

Next, 100 parts by weight of Asahi Kasei's “Asahi-Per Blue CR” as a pigment containing blue, 5 parts by weight of ethyl cellulose (manufactured by Kanto Chemical) as a binder resin, and 40 parts by weight of α-terpineol (manufactured by Kanto Chemical) as a solvent are used. A blue paste mixed and dispersed in a bead mill was prepared.

This blue paste is printed using a polyester 300 mesh screen stencil having a stripe opening, and a blue stripe pattern 11B having a line width of 250 μm, a pitch of 660 μm, and a film thickness of 10 μm is printed in a predetermined opening of the black stripe. Formed.

Similarly, using TM Color # 3330 (manufactured by Dainichi Seika) as a green pigment and Transoxide Red (manufactured by Dainichi Seika) as a red pigment, all were made into pastes at the same composition ratio and screened. The alignment of the plate was performed, and a green stripe pattern 11G and a red stripe pattern 11R were printed at predetermined positions. Both had a line width of 250 μm and a film thickness of 10 μm.

After that, at 420 ° C. for 60 minutes and 60
It is baked in a continuous process at 0 ° C. for 30 minutes to remove α-terpineol and ethyl cellulose, which are organic components, in the light-shielding layer 12 and the dye layer 11 by evaporation and burning, and further, the low-melting glass frit in the light-shielding layer 12. Was softened. Thus, the light shielding layer 1 made of the inorganic pigment and the low melting point glass
2, and a pigment layer 11 composed of an inorganic pigment of each color of blue, green, and red
B, 11G, and 11R were formed on the glass substrate 10.

Similarly, 100 parts by weight of the above-mentioned low melting glass frit were mixed with 2.5 parts of ethyl cellulose (manufactured by Kanto Chemical).
Parts by weight, 2- (2-ethoxyethoxy) ethanol 20
In addition to the above parts by weight, an overcoat paste was prepared by dispersing the mixture in a three-roll mill.

Thereafter, the overcoat paste is applied to a screen plate of polyester 300 mesh on a glass substrate 10 on which a light-shielding layer 12 of a stripe pattern and a dye layer 11 of a blue, green and red stripe pattern are formed at predetermined positions. The solid was applied so as to cover the entire area of the pattern. The applied film thickness was 20 μm.

Then, at 420 ° C. for 60 minutes and 600
Baked in a continuous process at 30 ° C. for 30 minutes.
2 (2-ethoxyethoxy) ethanol is removed by evaporation and burning, and the low melting glass frit is further softened;
A color filter having a structure in which a light-shielding layer 12, blue, green, and red dye layers 11B, 11G, and 11R and an overcoat layer 13 were sequentially laminated on a glass substrate 10 was manufactured (FIG. 1).

Through the above steps, the substrate, the light-shielding layer, and the overcoat layer were sealed with each other, and a color filter having a smooth upper surface was manufactured. The surface unevenness of this color filter was excellent in flatness within 1 μm. Further proceeding to a panel process, a film of ITO (Indium Tin Oxde) is formed on the upper surface of the color filter substrate by a sputtering method, and a transparent electrode is wired with an etching solution in which ferric chloride and hydrochloric acid are mixed using an arbitrary resist pattern as a mask. did.

The color filter substrate thus obtained was free from defects such as pinholes and disconnections in the wiring electrodes, and a good color filter substrate free from problems such as peeling, discoloration and cracking of the dye layer was obtained. FIG. 2 shows the measurement results of the spectral transmittance of the color filter.

Example 2 The following photosensitive resin composition was synthesized by the following procedure. 40 parts by weight of methacrylic acid, 40 parts by weight of methyl methacrylate, and 20 parts by weight of 2-hydroxyethyl methacrylate were mixed, and copolymerization was performed according to a conventional method using diethylene glycol monoethyl ether as a solvent. The solid content ratio was 40%.

The above copolymer was used as a binder resin, and 100 parts by weight of solids was used as a black pigment “T
500 parts by weight of M color # 3480, 300 parts by weight of the low melting glass frit prepared in Example 1, 80 parts by weight of tetraethylene glycol diacrylate (Toa Gosei: bifunctional acrylic monomer M240) as a photopolymerizable composition, light Polymerization initiator (Tokyo Kasei: 2,2-dimethoxy-
(2-phenylacetophenone) was mixed at a ratio of 30 parts by weight to obtain a paste for a light-shielding layer.

The above photosensitive paste was converted to polyester 300
A soda lime glass substrate 10 (coefficient of thermal expansion: 75 × 10 ⁻⁷ / ° C.) is solid-coated over the entire surface using a mesh screen plate, dried, and exposed to ultraviolet light through a chromium-deposited quartz mask having a stripe pattern. 0.1% Na ₂ CO ₃
The light-shielding region was developed and removed with an aqueous solution, and a light-shielding layer (black stripe) pattern 12 having a line width of 150 μm, a pitch of 220 μm, and a film thickness of 8 μm was formed by printing.

Subsequently, "Asahi-Per Blue CR" manufactured by Asahi Kasei as a blue pigment and "TM Color # 3330" manufactured by Dainichi Seika as a green pigment were used instead of a black pigment without blending a low melting point glass frit. Except for using "Transoxide Red" manufactured by Dainichi Seika as the red pigment, blue, green, and red photosensitive pastes were respectively prepared under the same conditions as those of the light-shielding layer.

The pastes of the respective colors thus obtained are applied to the entire surface of the glass substrate 10 on which a stripe-shaped light-shielding pattern is formed by using a screen plate of polyester 300 mesh and dried, and the chrome-deposited quartz mask is aligned. The exposure and development were repeated to form a blue stripe pattern 11B, a green stripe pattern 11G, and a red stripe pattern 11R.

The overcoat paste used in Example 1 was applied in a solid manner so as to cover the entire pattern in the same manner as in Example 1 to form an overcoat layer. Thereafter, firing is performed in a continuous process at 420 ° C. for 60 minutes and at 600 ° C. for 30 minutes in the air to remove organic components in the dye layer and the overcoat layer by evaporation and burning, and further softens the low melting glass frit. To form a light shielding layer 12 on the glass substrate 10.
A color filter having a structure in which a blue, green, and red dye layer 11 and an overcoat layer 13 were sequentially laminated was manufactured (FIG. 1).

By the above steps, the substrate, the light-shielding layer, and the overcoat layer are mutually sealed, and the surface irregularities are reduced.
A color filter having excellent flatness of 1 μm or less was manufactured. As a result of wiring a transparent electrode to be a paneling process on the upper surface of the color filter substrate, it is possible to obtain a good color filter substrate free from defects such as pinholes and disconnections and free from problems such as peeling, discoloration, and cracks of the dye layer. Was completed.

<Example 3> PbO55 as a glass raw material
Wt%, SiO ₂ 35 wt%, B ₂ O ₃ 5 wt%, Na ₂ O
Similarly, the mixture was melted in a crucible at a ratio of 2.5% by weight and 2.5% by weight of F ₂ , then cooled to obtain a glass powder, and then pulverized by a ball mill to obtain a low melting point having an average particle size of 3 to 7 μm. A glass frit was obtained. The glass frit thus produced had a softening point of 620 ° C. and a coefficient of thermal expansion of 53 × 10 ⁻⁷ / ° C.

Next, in the same manner as in Example 1, a black pigment, the low melting glass frit, ethyl cellulose, and α-terpineol were dispersed in a bead mill to prepare a light-shielding layer paste.

Similarly, a low-expansion non-alkali glass (OA-2, manufactured by NEC Corporation, thermal expansion coefficient: 48 × 10 ⁻⁷ / ° C.) substrate 10 was formed on a screen plate of polyester 300 mesh opened in a stripe shape. A light shielding layer (black stripe) pattern 12 having a line width of 150 μm, a pitch of 220 μm, and a film thickness of 8 μm was formed by printing.

Subsequently, "Asahi-Per Blue CR" manufactured by Asahi Kasei as a blue pigment and "TM Color # 3330" manufactured by Dainichi Seika as a green pigment were used instead of a black pigment without blending a low melting point glass frit. Except for using "Transoxide Red" manufactured by Dainichi Seika as the red pigment, blue, green, and red stripe patterns 11B, 11G, and 11R were formed on printing paper under the same conditions as the light-shielding layer.

Further, the above-mentioned low melting point glass frit 100
The weight part was added to 2.5 parts by weight of ethyl cellulose (manufactured by Kanto Kagaku) and 20 parts by weight of 2- (2-ethoxyethoxy) ethanol, and this was dispersed in a three-roll mill to prepare an overcoat paste.

Thereafter, this overcoat paste is applied to the glass substrate 10 on which the light-shielding layer 12 and the blue, green, and red pigment layers 11 are formed by patterning, using a polyester 300 mesh screen plate so as to cover the entire pattern. A film thickness of 20 μm was applied with a solid.

Next, at 420 ° C. in the atmosphere for 60 minutes and 64
It was baked in a continuous process at 0 ° C. for 30 minutes, and the organic components of the light-shielding layer, the dye layer and the overcoat layer were removed by evaporating and burning all together, and the low-melting glass frit was further softened. Thus, the light-shielding layer 12, blue,
A color filter having a structure in which green and red dye layers 11 and an overcoat layer 13 were sequentially laminated was manufactured (FIG. 1).

Through the above steps, the substrate 10 and the light shielding layer 12
And the overcoat layer 13 were sealed to each other to produce a color filter having strong adhesion and a smooth upper surface. As a result of measuring the surface unevenness, the surface was excellent in flatness within 1 μm. The glass substrate 10 has a coefficient of thermal expansion of 4
Although it was small at 8 × 10 ⁻⁷ / ° C., the thermal expansion coefficient difference with the low melting point glass frit was matched at 5 × 10 ⁻⁷ / ° C., and cracks in the light-shielding layer, each color dye layer, overcoat layer, etc. No problem such as occurrence occurred, and a good color filter substrate could be manufactured.

Example 4 PbO55 as a glass material
Wt%, SiO ₂ 35 wt%, B ₂ O ₃ 5 wt%, Na ₂ O
2.5% by weight, 2.5% by weight of F ₂ at an average particle size of 3 to
7 μm low melting glass frit (softening point: 620 ° C., thermal expansion coefficient: 53 × 10 ⁻⁷ / ° C.) and the copolymer resin obtained in Example 2 (methacrylic acid 40 / methyl methacrylate 40)
/ 100 weight parts of 2-hydroxyethyl methacrylate 20), 500 parts by weight of a black pigment, 300 parts by weight of the above low melting point glass frit, and tetraethylene glycol diacrylate (2, manufactured by Toa Gosei: 2) as a photopolymerizable composition. 80 parts by weight of a functional acrylic monomer M240) and 30 parts by weight of a photopolymerization initiator (manufactured by Tokyo Chemical Industry: 2,2-dimethoxy-2-phenylacetophenone) were mixed, and the resulting photosensitive paste was solidly mixed with OA-2. Glass substrate 10
It was applied on the upper surface, exposed and developed to form a light-shielding layer (black stripe) 12.

Then, instead of using a low melting point glass frit, instead of a black pigment, "Asahi-Per Blue CR" manufactured by Asahi Kasei as a blue pigment, "TM Color # 3330" manufactured by Dainichi Seika as a green pigment, Except for using `` Transoxide Red '' manufactured by Dainichi Seika as a red pigment, blue, green, and red photosensitive pastes were prepared under the same conditions as the light-shielding layer, and paste application, exposure, and development were repeated for each color. Blue, green, and red stripe patterns 11B, 11G, and 11R were formed. Next, using the above-mentioned overcoat paste using a low melting point glass frit, a solid coating was performed so as to cover the entire pattern. After forming up to the overcoat layer in this way, 420
Baked in a continuous process of 60 minutes at 60 ° C. and 30 minutes at 640 ° C., and the organic components of the light-shielding layer, the dye layer and the overcoat layer are removed by evaporating and burning at a time, and the low-melting glass is further melted. A light-shielding layer 12 and blue, green,
A color filter having a structure in which a red dye layer 11 and an overcoat layer 13 were sequentially laminated was manufactured (FIG. 1).

Through the above steps, the substrate, the light-shielding layer and the overcoat layer were mutually sealed, and a color filter having a smooth upper surface and free from cracks and warpage of the substrate was produced. As a result of wiring a transparent electrode to be a paneling process on the upper surface of the color filter substrate, it is possible to obtain a good color filter substrate free from defects such as pinholes and disconnections and free from problems such as peeling, discoloration, and cracks of the dye layer. Was completed.

Comparative Example 1 PbO70 was used as a glass raw material.
Wt%, SiO ₂ 20 wt%, B ₂ O ₃ 5 wt% ,, Na ₂
Similarly, the mixture was melted in a crucible at a ratio of 2.5% by weight of O and 2.5% by weight of F ₂ and then cooled to obtain a glass powder.
Pulverization was performed with a ball mill to obtain a low-melting glass frit having an average particle size of 3 to 7 μm. The glass frit thus produced has a softening point of 521 ° C. and a coefficient of thermal expansion of 68 × 10 ⁻⁷ / ° C.
Met.

100 parts by weight of this glass frit, “TM Color # 3” manufactured by Dainichi Seika used in Example 1 as a black pigment
480 "(100 parts by weight) as a binder resin was mixed with 5 parts by weight of ethyl cellulose (manufactured by Kanto Kagaku) and 40 parts by weight of α-terpineol (manufactured by Kanto Kagaku) as a solvent to prepare a light-shielding layer paste dispersed in a bead mill.

This light-shielding layer paste was printed on a screen plate of polyester 300 mesh having stripe openings, and a 150 μm line width and a pitch of 150 μm were formed on a soda lime glass substrate 10 (coefficient of thermal expansion: 75 × 10 ⁻⁷ / ° C.). 22
A light-shielding layer (black stripe) pattern 12 having a thickness of 0 μm and a thickness of 8 μm was formed by printing.

Next, 100 parts by weight of Asahi Kasei's "Asahi-Per Blue CR" as a pigment containing blue, 5 parts by weight of ethyl cellulose (manufactured by Kanto Kagaku) as a binder resin, and 40 parts by weight of α-terpineol (manufactured by Kanto Kagaku) as a solvent. A blue paste mixed and dispersed in a bead mill was prepared.

The blue paste is printed using a screen mesh of polyester 300 mesh having stripe openings, and a blue stripe pattern 11B having a line width of 250 μm, a pitch of 660 μm, and a film thickness of 10 μm is printed in a predetermined opening of the black stripe. Formed.

Similarly, using TM Color # 3330 manufactured by Dainichi Seika as a green pigment, and Transoxide Red manufactured by Dainichi Seika as a red pigment, all were made into pastes at the same blending composition ratio and screened. The alignment of the plate was performed, and a green stripe pattern 11G and a red stripe pattern 11R were printed at predetermined positions. Both had a line width of 250 μm and a film thickness of 10 μm.

After that, at 420 ° C. for 60 minutes and 60
It is baked in a continuous process at 0 ° C. for 30 minutes to remove α-terpineol and ethyl cellulose, which are organic components, in the light-shielding layer 12 and the dye layer 11 by evaporation and burning, and further, the low-melting glass frit in the light-shielding layer 12. Was softened. Thus, the light shielding layer 1 made of the inorganic pigment and the low melting point glass
2, and a pigment layer 11 composed of an inorganic pigment of each color of blue, green, and red
B, 11G, and 11R were formed on the glass substrate 10.

Similarly, 100 parts by weight of the above-mentioned low-melting glass frit was mixed with 2.5 parts of ethyl cellulose (manufactured by Kanto Chemical Co., Ltd.).
Parts by weight, 2- (2-ethoxyethoxy) ethanol 20
In addition to the above, the overcoat paste prepared by dispersing the overcoat paste with a three-roll mill was prepared, and the overcoat paste was formed on a glass substrate 10 on which a light-shielding layer 12 and blue, green, and red dye layers 11 were patterned in a stripe pattern. The paste was applied solid using a screen plate of polyester 300 mesh so as to cover the entire pattern. The coating thickness is 20μ
m.

Next, at 420 ° C. in the atmosphere for 60 minutes and 600
Baked in a continuous process at 30 ° C. for 30 minutes.
2 (2-ethoxyethoxy) ethanol is removed by evaporation and burning, and the low melting glass frit is further softened;
A color filter having a structure in which a light-shielding layer 12, blue, green, and red dye layers 11B, 11G, and 11R and an overcoat layer 13 were sequentially laminated on a glass substrate 10 was manufactured.

Although the surface of this color filter was smooth, ITO (Indiu) was formed on the upper surface in the panel process.
As a result of wiring a transparent electrode of (m Tin Oxde) by etching, the etching resistance was poor and a part of the overcoat glass was melted. For this reason, the wiring electrode was disconnected and defects such as discoloration and peeling occurred in the dye layer due to penetration of the etching solution.

Further, since the PbO component in the glass frit is large, the overcoat is not sufficiently amorphized and has poor transparency, and the peak transmittance of blue, green and red as a color filter is reduced by 10 to 20%. .

Comparative Example 2 PbO45 was used as a glass raw material.
Wt%, SiO ₂ 45 wt%, B ₂ O ₃ 5 wt%, Na ₂ O
2.5% by weight, 2.5% by weight of F ₂ at an average particle size of 3 to
7 μm low melting point glass frit (softening point 650 ° C., thermal expansion coefficient 44 × 10 ⁻⁷ / ° C.) and the copolymer resin obtained in Example 2 (methacrylic acid 40 / methyl methacrylate 40)
/ 2-hydroxyethyl methacrylate 20) with respect to 100 parts by weight of the solid content, 500 parts by weight of a black pigment pigment, 300 parts by weight of the low melting point glass frit, and tetraethylene glycol diacrylate (Toa Gosei: 80 parts by weight of a bifunctional acrylic monomer M240), a photopolymerization initiator (manufactured by Tokyo Chemical Industry: 2,2-dimethoxy-)
(2-phenylacetophenone) was mixed at a ratio of 30 parts by weight to obtain a paste for a light-shielding layer.

The above-mentioned photosensitive paste was applied onto the OA-2 glass substrate 10 in a solid state, and exposed and developed to form a stripe-shaped light-shielding layer (black stripe) 12.

Subsequently, stripe patterns 11B, 11G and 11R were formed in the same manner as in Example 4, and the entire pattern was solid-coated using the above-mentioned overcoat paste using a low-melting glass frit. . After forming up to the overcoat layer in this way, 420
Baked in a continuous process of 60 minutes at 70 ° C. and 30 minutes at 700 ° C., the organic components of the light-shielding layer, the dye layer and the overcoat layer are removed by evaporating and burning all together, and the low-melting glass is further melted. A light-shielding layer 12 and blue, green,
A color filter having a structure in which a red dye layer 11 and an overcoat layer 13 were sequentially laminated was manufactured.

Although there was no problem with the surface smoothness of the color filter and the etching resistance of the electrode wiring, the low melting point glass frit had a high softening point and was 700 ° C. for softening.
At such a firing temperature, the inorganic pigment in the dye layer could not satisfy the heat resistance, resulting in discoloration. When the spectral transmittance of the color filter was actually measured, a result as shown in FIG. 3 was obtained, and the peak transmittance of blue, green, and red was 30 to 40 as compared with FIG. % Decreased.

[0079]

According to the color filter of the present invention, it is possible to adhere the light-shielding layer and the dye layer on the glass substrate without cracking or distortion without deteriorating the spectral characteristics.
In addition, a color filter having excellent surface smoothness can be provided.
Therefore, there is no defect such as disconnection or pinhole of the electrode or the dielectric layer formed in the subsequent process, discoloration to the dye layer, crack, and peeling in this process, so that the reliability as the display panel is improved. It can be significantly improved. According to the method for manufacturing a color filter of the present invention, instead of firing three times for each layer, after forming the pattern of the light-shielding layer and the dye layer,
When baking is performed twice after forming the overcoat layer,
Alternatively, by performing the firing step only once, the manufacturing process can be simplified, thereby reducing the throughput and the manufacturing cost.

[0080]

[Brief description of the drawings]

FIG. 1 is a sectional view of a color filter of the present invention.

FIG. 2 shows a result of measuring a spectral transmittance of a color filter according to an embodiment of the present invention.

FIG. 3 shows a result of measuring a spectral transmittance of a color filter which is a comparative example of the present invention.

[Explanation of symbols]

 10 Glass substrate 11 Dye layer 11B Blue dye layer 11G Green dye layer 11R Red dye layer 12 Light-shielding layer 13 Overcoat layer

Claims (4)

[Claims] 1. A color filter in which a dye layer and a light-shielding layer are regularly arranged between a substrate and an overcoat layer formed on the substrate, wherein the dye layer is made of an inorganic pigment, and the light-shielding layer is made of an inorganic pigment. And the overcoat layer is made of a low-melting glass, and the light-shielding layer and the low-melting glass of the overcoat layer are made of PbO50.
65 wt%, a color filter characterized by containing a SiO ₂ 25 to 35 wt%. 2. The color filter according to claim 1, wherein the ratio of the low melting point glass in the light shielding layer is 30 to 400 parts by weight based on 100 parts by weight of the inorganic pigment. 3. The method for producing a color filter according to claim 1, wherein the light-shielding layer and the dye layer are patterned on a transparent substrate, and then baked, and then the overcoat layer is formed so as to cover the entire surface of the substrate. And forming a light-shielding layer, a dye layer, and an overcoat layer on the substrate after forming a pattern. 4. The method for manufacturing a color filter according to claim 1, wherein a light-shielding layer, a dye layer, and an overcoat layer are sequentially patterned on a transparent substrate and then fired collectively. A light-shielding layer, a dye layer and an overcoat layer.