JP3376783B2 - Color filter and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter which is provided in various display devices such as a plasma display and a liquid crystal display and a solid-state image pickup device and is used for reducing reflectance, color synthesis or color separation, and a manufacturing method thereof. .

[0002]

2. Description of the Related Art For example, in a liquid crystal display, a color filter is necessary for displaying in color. Therefore, as described in a known document (as an example, Tani et al., Technical Report of the Television Society of Japan, IDY94-112 (1994)), a color filter manufactured by a method such as a dyeing method or a pigment dispersion method is used. . This is to color a resin layer with an organic dye or an organic pigment to form a color filter. Also, in plasma displays, it has been proposed to use color filters to improve the contrast when displaying images (Wazu, Nikkei Electronics, 1993.
November 8th issue (NO.594) pp.215 etc.). Thus, in some display devices, a color filter is indispensable for color display and improving image quality.

By the way, in the case of a plasma display,
The manufacturing process includes a process of firing at about 600 ° C. If a color filter for a liquid crystal display is used as it is as a color filter for a plasma display, a material such as an organic material is included, so that a reaction such as combustion or decomposition occurs in the plasma display manufacturing process, and the color filter It is not possible to obtain the characteristics as.

As a solution to this problem, it has been proposed to disperse an inorganic pigment in a low melting glass and use it as a color filter (Sakai et al., Technical Report ED993 IPD113-8 (1986) of the Television Society). This is because a paste obtained by kneading a low-melting glass and 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 then baked to remove the binder resin and the solvent. A filter in which an inorganic pigment is dispersed in a low melting point glass is obtained. In this case, since the color filters are all made of an inorganic material, they can withstand the high temperature process involved in plasma display fabrication.

In view of the structure of the plasma display, electrodes and dielectrics are formed on this color filter. Therefore, it is important to prevent the disconnection and the pinhole, and for that purpose, it is desirable that the irregularities on the substrate due to the filter layer be small and as flat as possible.

However, as shown in FIG. 1, this color filter has a certain thickness due to the low melting point glass 11 and the pigment 12 constituting the color filter, and the thickness is 10
In some cases, the asperities are formed on the substrate 10 in some cases.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a color filter in which unevenness on a substrate due to a color filter layer is reduced, and a color filter therefor. It is to provide a manufacturing method.

[0008]

To solve this problem, the first aspect of the present invention is to provide a pigment paste on a substrate.
After forming a pattern of a predetermined shape by baking the substrate
After removing the components other than the pigment from the pigment paste,
A pattern of a predetermined shape consisting of only the material, and then,
An overcoat layer made of a transparent material made of either a low melting point glass or a transparent inorganic oxide is collectively provided on the pattern and its peripheral portion, and the overcoat layer is provided .
Is a color filter including the pigment and being fixed .

According to a second aspect of the present invention, after the black matrix layer is formed on the substrate, the opening portion of the black matrix layer and the peripheral portion thereof are formed into a predetermined shape with a pigment paste.
After forming the pattern of
Remove all components except the pigment from the paste,
And a pattern of a predetermined shape consisting only of a pigment, and an overcoat made of a transparent material composed of either low melting point glass or a transparent inorganic oxide, together with the pattern and a peripheral portion thereof. A coat layer is provided , and the overcoat layer contains the pigment.
A color filter characterized by being adhered to the back . It is what

A third aspect of the present invention is the color filter according to the first or second aspect, wherein an inorganic pigment is used as the pigment.

A fourth aspect of the present invention is the color filter according to the second aspect, wherein a thin film of a metal material or an inorganic pigment is used as the black matrix layer.

[0012] According to a fifth aspect, the pigment paste is formed on the base material.
After forming a pattern of a predetermined shape in, baking on the substrate
To remove components other than the pigment from the pigment paste,
Make a pattern of a predetermined shape consisting of pigment only, and then
The pattern and the overcoat layer made of a transparent material made of either low-melting glass or a transparent inorganic oxide collectively to its periphery is provided, the overcoat layer
The method for producing a color filter is characterized in that the above-mentioned pigment is included and fixed, and the pigment is fixed onto a base material.

According to a sixth aspect of the present invention, after the black matrix layer is formed on the base material, a pattern of a predetermined shape is formed in the opening of the black matrix layer with a pigment paste.
After that, the substrate is baked and the pigment paste is added to the pigment.
Except for components other than the above, a predetermined pattern consisting of only the pigment is formed, and then the pattern and its peripheral portion are collectively covered with a transparent material made of either low-melting glass or a transparent inorganic oxide. the coat layer is provided, Oh
Including and fixing the pigment in the overcoat layer
Then, the method for producing a color filter is characterized in that the pigment is fixed onto the substrate.

According to a seventh aspect of the present invention, as the patterning method, any one of a printing method, a photolithography method, an electrophotographic method, and an electrodeposition method is used, and the color according to the fifth or sixth aspect. This is a filter manufacturing method.

Further, claim claim 8, using a coating method using a liquid phase method or vapor phase method The method for forming the overcoat layer, in the case of liquid-phase method and performing a baking after coating 6. The method for producing a color filter according to 6 or 7. It is what

[0016]

[0017]

[0018]

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. An inorganic pigment is preferably used as the pigment in the present invention. Examples of the inorganic pigment include Fe ₂ O ₃ as a red pigment and TiO ₂ —CoO—N as a green pigment.
IO-ZnO, as the blue pigment CoO-Al ₂ O ₃ can be used.

The transparent material used for the overcoat layer in the present invention may be lead borosilicate glass, which is a low melting point glass, but is not limited thereto. In addition, transparent inorganic oxides such as SiO ₂ and composite oxides of SiO ₂ and TiO ₂ can be used.

As the thin film of the metallic material used as the material for the black matrix in the present invention, metallic chromium, chromium oxide or the like can be used, and as the inorganic pigment, FeC.
Fe, Mn, C including r ₂ O ₄ and CuMn ₂ O ₄
A complex oxide such as r can be applied, and other metal materials and inorganic pigments can be mixed and used.

[0022]

As a method for patterning the pigment in the present invention, in the printing method, a printing paste is supplied onto a screen plate having an opening of a desired pattern, and the printing paste is rubbed with a flexible squeegee to open the opening. Screen printing method to extrude the paste and print it on the substrate, or to form a metal plate on which a desired pattern is formed, fill the pattern part with paste, transfer the filled paste to a blanket, and then paste on the blanket It is possible to use a lithographic offset printing method or the like in which the is transferred to the substrate.

As the photolithography method,
A method in which a paste prepared by kneading a pigment with an appropriate photosensitive resin is applied on a substrate, exposed by using a predetermined photomask, and then developed and patterned, or a method in which the pigment is applied on the substrate and then the pigment is used. A method of coating a photosensitive resin on the surface, exposing it using a predetermined photomask, and then performing development and etching, and patterning this.
Alternatively, apply a resin having photo-adhesiveness onto the substrate, expose it using a predetermined photomask, and make only the portion to which the pigment adheres sticky, and then spray the pigment to fix the pigment on the adhesive layer. A patterning method or the like can be used.

In electrophotography, a pigment is formed into a toner by using a known resin, and the toner is adhered to a selenium photoreceptor on which a latent image is formed, and then transferred to a substrate to form a pattern. it can.

As the electrodeposition method, an electrodeposition coating in which a pigment is dispersed in an alkyd resin or the like in water is prepared, and a substrate provided with a transparent conductive film such as a patterned ITO film is immersed in the electrodeposition coating. A pattern can be formed on the transparent conductive film by applying electricity.

In the method of providing an overcoat layer made of a transparent material collectively on the pigment and the peripheral portion thereof in the present invention, the liquid phase method is a metal alkoxide by a screen printing method, a dip coating method, or a spin coating method. Examples include a method of forming a material layer having light transparency by applying this to a substrate and then baking it.
Examples of the vapor phase method include a vapor deposition method and a sputtering method. These manufacturing methods are examples, and it is preferable to select a suitable method without being limited thereto.

According to the present invention, as shown in FIG.
The pigment 12 is densely and uniformly arranged on the substrate 10. Since the overcoat layer 13 made of a transparent material is collectively provided on the pigment and its peripheral portion, the pigment is included in the overcoat layer material and fixed thereto, so that a flat pattern with a small step between pixels is formed. Is formed. Ideally, the unevenness on the substrate 10 is eliminated. For this reason, disconnection and pinholes in electrodes and dielectric layers formed in a later step are less likely to occur, so that reliability as a display can be improved.

Then, the film thickness of the desired pattern formed on the substrate depends on the particle diameter of the pigment set according to the spectral characteristics and the coating amount of the material having light transmittance. That is, by adjusting this setting, it is possible to reduce the unevenness on the substrate surface and achieve flatness.

[0030]

[0031]

EXAMPLES Example 1 As shown in FIG. 3 , a blue pigment paste 1 was applied to a glass substrate 10.
4 using a 300 mesh screen printing plate to a width of 10
A pattern of 0 μm and a length of 4 mm was printed.

The blue pigment paste 14 used here is used.
Is a blue pigment (Asahi Kasei Co., Ltd .: “Asahi Super Blue CR”) 5 parts ethyl cellulose (Kanto Chemical Co., Inc.) α-terpineol (Kanto Chemical Co., Ltd.)
In addition to 50 parts of a 5 wt% solution, this was kneaded with a three-roll mill to form a paste.

[0033] The air the glass substrate 10 and baked at 580 ° C. 10 minutes and to remain only pigments 12 on the glass substrate 10 as shown in FIG. It should be noted that ethyl cellulose and α-terpineol in the blue pigment paste evaporate or burn in this step and are consequently removed.

As shown in FIG. 5 , the glass paste 15 is applied to the glass substrate 10 on which the pigment 12 remains on the substrate.
The overcoat material 15 was printed using a 0 mesh screen printing plate. In this step, a solid pattern was printed.

The glass paste 15 used here is lead borosilicate glass (manufactured by Nippon Electric Glass Co., Ltd .: “GA-
9 ") 75 parts of ethyl cellulose (Kanto Chemical Co., Inc.)
25 parts of 2- (2-ethoxyethoxy) ethanol (manufactured by Kanto Kagaku Co., Ltd.) in 10 wt%, and the mixture was kneaded with a three-roll mill to form a paste.

By firing the glass substrate 10 in air at 580 ° C. for 10 minutes, as shown in FIG. 6 , the overcoat layer 1 of low melting point glass is formed on the glass substrate 10.
3 was formed, whereby the pigment 12 was fixed to the glass substrate 10. It should be noted that ethyl cellulose and 2- (2-ethoxyethoxy) ethanol in the glass paste were evaporated or burned in this step and were consequently removed.

As a result, a color filter having excellent flatness was obtained. The measurement result of the spectral transmittance is shown in FIG. 7 . The unevenness on the substrate at this time was about 1 μm.

<Example 2> The glass substrate 10 was coated with the photosensitive blue pigment paste 14 on the entire surface of the substrate using a 300 mesh screen printing plate, and then exposed using an ultrahigh pressure mercury lamp using a predetermined photomask, Then, the pattern was developed with pure water to obtain a pattern having a width of 100 μm and a length of 4 mm.

The blue pigment paste 14 used here is used.
Is a blue pigment (Asahi Kasei Co., Ltd .: "Asahi Super Blue CR") 15 parts, 30 parts of hydroxypropyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.) as a photosensitive resin, and dipentaerythritol hexaacrylate (Toa Gosei ( Co., Ltd .: "Aronix M-400") 30 parts, and then 2- (2-ethoxyethoxy) ethanol (Kanto Chemical Co., Inc.) 90 parts as a solvent, and kneading them with a three-roll mill. Then, what added 5 parts of benzyl dimethyl ketal (Toagosei Co., Ltd .: "Aronix C-101") as a reaction initiator was used.

The glass substrate 10 was baked in air at 580 ° C. for 10 minutes so that only the pigment 12 remained on the glass substrate 10. The photosensitive resin, the solvent, and the reaction initiator in the blue pigment paste are evaporated or burned in this step, so that they are removed as a result.

[0041] As a result, the pigment 12 to obtain a color filter as shown in FIG. 6 to form a similarly overcoat layer 13 as in Example 1 on the glass substrate 10 left on the substrate. The measurement result of the spectral transmittance and the unevenness on the substrate were the same as in Example 1.

<Example 3> Blue pigment (Asahi Kasei Co., Ltd.)
(Manufactured by: "Asahi Super Blue CR") and 10 parts by weight of 90 parts of a styrene-n-butyl methacrylate copolymer (manufactured by Sanyo Kasei Co., Ltd .: "Heimer SBM-73") while kneading, and after cooling, hammered. The particles were coarsely crushed with a mill, pulverized with a jet mill, and then classified to obtain colored particles having an average particle size of 10 μm, polytrifluoroethyl-α-
Chloroacrylate (manufactured by Toray Industries, Inc.) was adhered by a spray dry method, and this was treated with hot air by a spheroidizing device for thermoplastic particles to obtain a toner.

This tonerized pigment was adhered to a selenium photoreceptor on which a latent image of a predetermined pattern was formed in advance according to a conventional method, and the adhered tonerized pigment was heated to 100 ° C.
Transferred to the glass substrate 10 heated to 580
The resin is removed by baking at 10 ° C. for 10 minutes, and the glass substrate 10
Width 100 μm, length 4 with only pigment 12 remaining on top
A mm pigment pattern was obtained.

An overcoat layer 13 was formed on the glass substrate 10 on which the pigment 12 remained on the substrate in the same manner as in Example 1 to obtain a color filter. The measurement result of the spectral transmittance and the unevenness on the substrate were the same as in Example 1.

Example 4 The color filter of the present invention can be manufactured by the following steps. First, 15 parts of a blue pigment (Asahi Kasei Co., Ltd .: "Asahi Super Blue CR") was added to an aqueous alkyd resin varnish (Dainippon Ink and Chemicals, Inc.).
(Manufactured by: "Waterzor S140C") and 45 parts of water were mixed to prepare a dispersed electrodeposition coating composition.

A glass substrate 10 on which a transparent conductive film having a predetermined pattern is formed is immersed in this electrodeposition coating material according to a standard method in advance, and the electrodeposition coating material (Ac or Dc) is attached to the electrodes by energizing at 60 V for 60 seconds. The glass substrate 10 to 5
The resin component was removed by baking at 80 ° C. for 10 minutes, and as shown in FIG. 4 , only the pigment 12 remained on the glass substrate 10 to obtain a pattern of the pigment having a width of 100 μm and a length of 4 mm.

An overcoat layer 13 was formed on the glass substrate 10 on which the pigment 12 remained on the substrate in the same manner as in Example 1 to obtain a color filter. The measurement result of the spectral transmittance and the unevenness on the substrate were the same as in Example 1.

Example 5 In the same manner as in Example 1, after leaving only the pigment 12 on the glass substrate 10, a silica coating agent by a sol-gel method (Nippon Soda Co., Ltd.) was used as an overcoat material. (Made by: "Atron NSi-310")
2 parts of 10 parts of ethyl cellulose (manufactured by Kanto Chemical Co., Inc.)
(2-ethoxyethoxy) ethanol (Kanto Chemical Co., Inc.)
10 parts by weight of 10% by weight solution, and a well-mixed mixture was used as the overcoat material 15 and printed using a 300 mesh screen printing plate. In this step, a solid pattern was printed.

The glass substrate 10 is baked in air at 580 ° C. for 10 minutes to form an overcoat layer 13 of low melting point glass on the glass substrate 10, whereby the pigment 12 is fixed to the glass substrate 10. I got a color filter. The measurement result of the spectral transmittance and the unevenness on the substrate were the same as in Example 1.

Example 6 In the same manner as in Example 1, after leaving only the pigment 12 on the glass substrate 10, SiO ₂ was used as the overcoat layer 13 in the glass substrate 10 by using a vapor deposition apparatus according to a conventional method. A film was formed thereon, and the pigment 12 was fixed on the glass substrate 10 to obtain a color filter. The measurement result of the spectral transmittance and the unevenness on the substrate were the same as in Example 1.

Comparative Example A paste containing a blue pigment and a low melting point glass was printed on a glass substrate under the same conditions as in Example 1 to obtain a pattern having a width of 100 μm and a length of 4 mm. In addition, the paste used here is 2- (2-ethoxyethoxy) ethanol of 75 parts of low melting point lead glass (Nippon Electric Glass Co., Ltd .: "GA-9") of ethyl cellulose (Kanto Chemical Co., Inc.). (Kanto Chemical Co., Inc.) 10 wt% solution 2
In addition to 5 parts, 26 parts of a paste prepared by kneading this with a three-roll mill was used to prepare a blue pigment (Asahi Kasei Co., Ltd .:
1 part of "Asahi Super Blue CR" was added, and this was kneaded with a three-roll mill to form a paste.

The glass substrate was heated in air at 580 ° C. for 10 minutes.
By firing for minutes, a color filter in which the pigment was dispersed in the low melting point glass was obtained. The measurement result of the spectral transmittance is
As shown in FIG. 8 , this spectral transmittance is almost the same as that of the first embodiment. However, the unevenness on the substrate was about 10 μm.

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

As described above, according to the color filter and the method of manufacturing the same of the present invention, the pigment is densely and uniformly arranged on the substrate. Further, the pigment can be fixed by the overcoat layer, and the unevenness on the substrate due to the color filter layer can be reduced. For this reason, disconnection and pinholes in electrodes and dielectric layers formed in a later step are less likely to occur, and thus reliability as a display can be improved.

[Brief description of drawings]

FIG. 1 is a schematic view of a cross section of a conventionally manufactured color filter.

FIG. 2 is a schematic cross-sectional view of an ideal color filter in the color filter according to the present invention.

FIG. 3 is a cross-sectional view showing a pigment paste applying step in one example relating to the color filter of the present invention.

FIG. 4 is a cross-sectional view showing a pigment paste firing step in one example relating to the color filter of the present invention.

FIG. 5 is a cross-sectional view showing an overcoat material coating step in one example relating to the color filter of the present invention.

FIG. 6 is a cross-sectional view showing a step of firing an overcoat material in one example relating to the color filter of the present invention.

FIG. 7 is an example of a spectral transmittance measurement result of a color filter in an example relating to the color filter of the present invention.

FIG. 8 is an example of a spectral transmittance measurement result of a color filter in a comparative example relating to the color filter of the present invention.

Continuation of the front page (56) References JP-A-5-224010 (JP, A) JP-A-4-134401 (JP, A) JP-A-5-288926 (JP, A) (58) Fields investigated (Int .Cl. ⁷ , DB name) G02B 5/20 101

Claims (8)

(57) [Claims] 1. A pigment paste having a predetermined shape is coated on a substrate.
After the turn is formed, the substrate is baked to form the pigment paper.
Where the components other than the pigment are removed from the
With a pattern of a fixed shape, thereafter, an overcoat layer made of a transparent material made of either low melting point glass or a transparent inorganic oxide is collectively provided on the pattern and its peripheral portion, and the overcoat layer is Includes pigment
A color filter characterized in that it adheres and is fixed . 2. A black matrix layer is formed on a substrate, and then a pattern of a predetermined shape is formed with a pigment paste on the opening and the peripheral portion of the black matrix layer.
After that, the substrate is baked to remove the pigment from the pigment paste.
A pattern with a predetermined shape that consists of only the pigment, with the external components removed.
Then, a pattern of a predetermined shape consisting of only the pigment and an overcoat layer made of a transparent material made of either low melting point glass or a transparent inorganic oxide are collectively provided on the pattern and its peripheral portion. , Said over
A color filter, wherein the coat layer includes the pigment and is fixed . 3. The color filter according to claim 1, wherein an inorganic pigment is used as the pigment. 4. A thin film of a metal material or an inorganic pigment is used as the black matrix layer.
The color filter described in. 5. A pigment paste having a predetermined shape is applied on a base material.
After the turn is formed, the substrate is baked to form the pigment paper.
Where the components other than the pigment are removed from the
A constant shape of the pattern, providing an overcoat layer made of a transparent material composed of any one of the patterns and collectively low melting glass or a transparent inorganic oxide in its periphery Thereafter, the at overcoat layer Including pigment
A method for producing a color filter, characterized in that the pigment adheres to the base material and the pigment adheres to the base material. 6. A black matrix layer is formed on a substrate, and then a pigment paste is placed in the opening of the black matrix layer.
After forming a pattern of a predetermined shape on the
To remove components other than pigment from the pigment paste
Then, a predetermined pattern consisting of only the pigment is formed, and then an overcoat layer made of a transparent material made of either low melting point glass or a transparent inorganic oxide is collectively provided on the pattern and its peripheral portion. Overcoat layer
A method for producing a color filter, comprising the steps of including and fixing the pigment, and fixing the pigment on a substrate. 7. The patterning method includes any one of a printing method, a photolithography method, an electrophotographic method, and an electrodeposition method.
Or the method for manufacturing a color filter according to any one of 6 above. 8. A liquid phase method using a coating method by a liquid phase method or a gas phase method as a method for forming the overcoat layer.
In the case of, the method for producing a color filter according to claim 6 or 7 , wherein baking is performed after coating .