JPH0618716A - Production of color filter - Google Patents

Abstract

PURPOSE:To obtain the color filter having mosaic patterns by using a thin film forming method for forming pigment films on conductors by effecting an electrolysis in an aq. micell colloidal soln. dispersed with pigments by using a surfactant to be charged by the electrolysis. CONSTITUTION:The patterns for film forming R, G, B are respectively patterned by a resist prior to the electrolysis in the aq. pigment colloidal soln. This resist is used as a partial mask. A black resist is used for the resist and is used as a black matrix.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter used for a liquid crystal display.

[0002]

2. Description of the Prior Art Pigment particles that are insoluble or sparingly soluble in water and a surfactant and a supporting electrolyte that are charged by an electric field are used as basic components to prepare a micellar colloid aqueous solution of a pigment in which the pigment particles are surrounded by the surfactant. RGB3 is formed by a thin film forming method in which the micelles are destroyed by electrolysis to deposit pigment particles on a conductor to form a pigment thin film.
Japanese Patent Application No. 2-24603 is filed for producing a color filter composed of primary colors and using it as a color filter for a liquid crystal panel. By the way, the color filter manufactured by the above thin film forming method is shown in FIG.
As shown in, using a transparent electrode formed on the substrate,
It is characterized in that a pigment thin film is formed thereon, and the electrode used for electrolytically forming the pigment thin film is also used for driving a liquid crystal. Since the liquid crystal driving electrode is located under the pigment thin film, we call it the electrode substructure for convenience, but the electro-optical characteristics of the liquid crystal panel manufactured using the color filter of the electrode substructure is called. When a liquid crystal drive voltage is applied to the panel, a voltage drop occurs due to the color filter on the electrodes, so compared to a liquid crystal panel using a color filter with an electrode-on-structure in which electrodes are formed on a pigment thin film, When a voltage is applied to the liquid crystal and the liquid crystal starts to rise, that is, the threshold voltage is
It gets expensive. Particularly in an active matrix type liquid crystal panel, a high voltage is required to drive the switching element, and from the viewpoint of the withstand voltage of the IC for driving the liquid crystal, it is a problem that the threshold voltage becomes higher, which is a problem. The voltage needs to be lowered.
In addition, in the case of positive display with good color tone, in order to obtain contrast, the voltage is applied to the complete B
It must be in the rack state, but for that,
A voltage higher than that of the negative display is required, and also from this point, the threshold voltage needs to be lowered.

For these reasons, it is ultimately desirable to have a structure having only liquid crystal on the electrodes. However, the electrode superposition structure has a low manufacturing yield, and is disadvantageous in that it is higher in cost than the electrode subposition structure.
There has been a demand for a color filter that can be expected to have improved characteristics with an electrode substructure. In this case, the color filter of the electrode underlay method can reduce the film thickness of the pigment film layer to less than half that of the conventional dyeing method, pigment dispersion method, or electrodeposition method. Although attached structure,
It was possible to fabricate a panel with good characteristics equivalent to the structure on which the electrode was mounted.

However, in the color filter according to the present method, the driving electrode is used as it is as the electrode for forming the pigment film, so that the RGB color filter pattern has a stripe structure. For example, the pattern is as shown in FIG. The pattern of FIG. 5 has no problem in resolution in medium to large screens of 6 inch class or more used for personal computers, etc., but in the 3 to 4 inch class currently used as a liquid crystal television, the resolution decreases and the image quality is improved. Will decrease. Therefore, generally, a so-called mosaic pattern as shown in FIG. 1 is predominant. Such a mosaic pattern cannot be manufactured in principle by the film forming method according to the present method.

[0005]

As described above, when this method is used as a color filter for a small liquid crystal panel such as a liquid crystal television, a mosaic color filter required for high resolution and high image quality is obtained. Manufacturing is impossible in principle. However, when the stripe pattern as shown in FIG. 5 used in the conventional method is used, the resolution becomes poor and the image quality is deteriorated. Further, even if the pigment film is made thin, there is no voltage loss, and it is also a problem to obtain the characteristics comparable to the above-mentioned electrode mounting structure in order to improve the image quality.

[0006]

The method for producing a color filter of the present invention comprises a pigment particle which is insoluble or sparingly soluble in water, a surfactant and a supporting electrolyte which are charged by an electric field as basic components, and the pigment particle is used in the interface. In a method for producing a color filter in which a micelle colloid aqueous solution of a pigment surrounded by an activator is prepared, the micelle is destroyed by electrolysis, pigment particles are deposited on a conductor, and a pigment thin film is formed, a) electrolysis is performed, A first step for forming an electrode having a predetermined stripe pattern for forming a thin film on a transparent substrate, b) applying a positive resist on the entire surface of the substrate on which the electrode is formed, and c) The second step of forming an electrode exposed surface of an arbitrary pattern by exposure and development, d) In the second step, the resist is developed and a first color is formed on the exposed electrode pattern. A third step of forming a pigment film using the thin film forming method, e) In the portion other than the portion where the pigment film of the first color is formed, the above step c) d) is repeated to form a pigment film of the second color. A fourth step of forming using a thin film forming method, f) repeating the above step c) d) in a portion other than forming the first and second color pigment films to form a third color pigment film It is characterized by comprising a fifth step of forming by using the forming method, g) a sixth step of forming a transparent conductive layer on the entire surface, and h) a seventh step of peeling the resist.

In the method for manufacturing a color filter described above, a) a first step for forming an electrode having a predetermined stripe pattern for electrolysis to form a thin film on a transparent substrate; b. ) A positive resist or a negative resist is applied to the entire surface of the substrate on which the electrode is formed, and c) the second step of forming an electrode exposed surface of an arbitrary pattern by exposure and development, d) the resist in the second step Is developed, and a third step of forming a pigment film of the first color on the exposed electrode pattern using the thin film forming method, e) a third step of removing the resist after step d), f) By repeating steps b) c) d) e), a fourth step of forming a second color in a portion other than the portion where the pigment film of the first color is formed, and g) repeating steps b) c) d). , First and second color pigments Other than the film formation, a fifth step of forming a third color, h) a sixth step of forming a transparent conductive layer on the entire surface, and i) a seventh step of removing the resist may be performed.

If a black resist is used as the resist used when forming the pattern for forming the third color, the process can be further simplified.

Furthermore, in the above manufacturing process, a black resist may be used in place of the resist from the beginning. That is, in that case, a) a first step for forming an electrode having a predetermined pattern on a transparent substrate for electrolysis to form a thin film, b) on the entire surface of the substrate on which the electrode is formed, A positive type black resist in which a dye or a pigment is dispersed or dissolved is applied, and c) the second step of forming an arbitrary pattern on the electrode by exposure and development, and d) the electrode in which the resist is developed in the second step. Third step of forming a pigment film of the first color on the pattern by using the thin film forming method, e) Repeating the above steps c) and d) in a portion other than the portion where the pigment film of the first color is formed. Fourth step of forming a pigment film of a color using the thin film forming method, f) Repeating the above steps c) d) in a portion other than forming the pigment film of the first color and the second color, the third color Using the thin film forming method Fifth step of forming, g) characterized by comprising the sixth step of forming on the entire surface transparent conductive layer.

This method is particularly characterized by using the black resist as it is as a black matrix thereafter.

Further, in this case, the step of forming the transparent conductive layer in the sixth step g) may be omitted.

[0012]

The object of the present invention is to make it possible to manufacture a color filter having a mosaic pattern, which could not be manufactured by this method in the past, and even if it is used in a small liquid crystal television, etc. By providing a color filter capable of obtaining image quality, and forming a conductive material on the pigment film, the conductive material is contained inside the porous pigment film, which is a deposited film of pigment fine particles, The lower electrode 2 and the pigment film 3 are electrically connected to each other to impart conductivity to the pigment, which is usually an insulator, and as a result, it is possible to provide a color filter having characteristics comparable to those of the above-mentioned electrode superposition structure. In that case, by removing the resist after film formation, the pigment films are not electrically connected to each other, and the lower electrodes are not electrically connected to each other, so that conductivity can be imparted only to the pigment film, and the pigment film can be used as a color filter for an MIM panel. . Further, when it is used as a color filter for a TFT panel, the color filter layer side does not require a patterned electrode in particular, so that it is sufficient to impart conductivity to the entire surface, and therefore it is not particularly necessary to peel off the resist. Further, it is an object of the present invention to provide a manufacturing method in which the resist used in the process is directly used as a black matrix and the process is short.

[0013]

【Example】

Example 1 An ITO film, which is a transparent electrode, was formed on a glass substrate, and ITO was patterned into an electrode pattern as shown in FIG.

A pigment film was formed on this electrode by the following method to prepare a color filter.

(1) A positive resist (OFPR800 manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied to the entire surface of the substrate, prebaked at 90 ° C., and then exposed and developed using a mask having the pattern of FIG. 4 on the substrate.

(2) Using the substrate after development, electrolysis was performed in the following pigment colloid aqueous solution.

Monochlorocopper phthalocyanine 20 mM (blue pigment) Ferrocenyl PEG 1 mM (surfactant having redox reactivity / manufactured by Dojindo) LiBr (supporting salt) 0.1 M Specifically, the substrate was placed in this pigment colloid aqueous solution. Of I
The TO electrode was brought into contact with the + electrode, a stainless steel substrate was used as the cathode, and electrolysis was performed at a constant potential of +0.4 V for 10 minutes. As a result, a blue film was formed on the substrate except where it was masked by the resist.

(3) Baking at 100 degrees Celsius for 30 minutes, 10
The resist was stripped in an aqueous KOH solution.

(4) Next, exposure and development were performed in the same manner as in (1). At this time, the mask has the pattern of FIG.
A mask that was slid horizontally for the pixels was used.

(5) In the same manner as in (2), a red film was formed as the second color. At this time, the following composition was used as the pigment colloid aqueous solution.

Dianthraquinolyl red 20 mM (red pigment) ferrocenyl PEG 2 mM LiBr (supporting salt) 0.1 M Specifically, in the pigment colloid aqueous solution, ITO of the substrate was used.
The electrode was brought into contact with the + electrode, a stainless steel substrate was used as the cathode, and electrolysis was performed for 30 minutes at a constant potential of + 0.9V.
As a result, a red film was formed on the substrate other than where it was masked by the resist (including the blue film portion).

(6) After firing at 100 ° C. for 30 minutes,
The resist was stripped in a 10% KOH aqueous solution.

(7) Next, exposure and development were performed in the same manner as in (4). At this time, as the mask, a mask in which the pattern of FIG. 4 was further slid laterally by one pixel was used.

(8) A green film was formed as the third color in the same manner as in (5). At this time, the following composition was used as the pigment colloid aqueous solution.

Brominated copper phthalocyanine chloride 20 mM (green pigment) Ferrocenyl PEG 1.5 mM LiBr (supporting salt) 0.1 M Specifically, in the aqueous pigment colloid solution, the substrate I
The TO electrode was brought into contact with the + electrode, a stainless steel substrate was used as the cathode, and electrolysis was carried out at a constant potential of +0.5 V for 15 minutes. As a result, a green film was formed on the substrate other than where it was masked by the resist (including the blue and red film portions).

(9) Firing at 100 degrees Celsius for 30 minutes.

(10) ITO, which is a transparent conductive film, is formed on the entire surface of the RGB formation substrate by sputtering.

(11) The resist was stripped in a 10% KOH aqueous solution.

According to the procedure as described above, a color filter having a pattern in which three colors of RGB are arranged in a mosaic pattern and having conductivity can be formed.

(Example 2) In the method for producing a color filter described in Example 1, in step (7), a black pigment resist was used in place of the normal positive resist to produce a color filter. Further, the step (11) was omitted, and the other steps were exactly the same as in Example 1. As a result, with the same man-hours as in Example 1, a color filter having a black matrix formed could be manufactured.

Example 3 An ITO film as a transparent electrode was formed on a glass substrate, and ITO was patterned into an electrode pattern as shown in FIG.

A pigment film was formed on this electrode by the following method to prepare a color filter.

(1) A positive resist was applied to the entire surface of the substrate, prebaked at 90 ° C., and then exposed and developed using a mask having the pattern of FIG. 4 on the substrate.

(2) Using the substrate after development, electrolysis was performed in the following pigment colloid aqueous solution.

Monochlorocopper phthalocyanine 20 mM (blue pigment) ferrocenyl PEG 1 mM (surfactant having redox reactivity / manufactured by Dojindo) LiBr (supporting salt) 0.1 M Specifically, the substrate was placed in this pigment colloid aqueous solution. Of I
The TO electrode was brought into contact with the + electrode, a stainless steel substrate was used as the cathode, and electrolysis was performed at a constant potential of +0.4 V for 10 minutes. As a result, a blue film was formed on the substrate except where it was masked by the resist.

(3) Firing at 90 degrees Celsius for 10 minutes.

(4) Next, exposure and development were carried out in the same manner as in (1). At this time, the mask has the pattern of FIG.
A mask that was slid horizontally for the pixels was used.

(5) In the same manner as (2), a red film was formed as the second color. At this time, the following composition was used as the pigment colloid aqueous solution.

Dianthraquinolyl Red 20 mM (red pigment) Ferrocenyl PEG 2 mM LiBr (supporting salt) 0.1 M Specifically, in the pigment colloid aqueous solution, the ITO of the substrate was used.
The electrode was brought into contact with the + electrode, a stainless steel substrate was used as the cathode, and electrolysis was performed for 30 minutes at a constant potential of + 0.9V.
As a result, a red film was formed on the substrate other than where it was masked by the resist (including the blue film portion).

(6) Firing at 90 degrees Celsius for 10 minutes.

(7) Next, exposure and development were carried out in the same manner as in (4). At this time, as the mask, a mask in which the pattern of FIG. 4 was further slid laterally by one pixel was used.

(8) A green film was formed as the third color in the same manner as (5). At this time, the following composition was used as the pigment colloid aqueous solution.

Brominated copper phthalocyanine chloride 20 mM (green pigment) ferrocenyl PEG 1.5 mM LiBr (supporting salt) 0.1 M Specifically, in the aqueous pigment colloid solution, the substrate I
The TO electrode was brought into contact with the + electrode, a stainless steel substrate was used as the cathode, and electrolysis was carried out at a constant potential of +0.5 V for 15 minutes. As a result, a green film was formed on the substrate other than where it was masked by the resist (including the blue and red film portions).

(9) Firing at 100 degrees Celsius for 30 minutes.

(10) ZnO, which is a transparent conductive film, was formed on the entire surface of the RGB formation substrate by vapor deposition.

(11) The resist was stripped in a 7% KOH aqueous solution.

By the above procedure, it was possible to form a color filter in which patterns of three colors RGB are arranged in a mosaic pattern and which has conductivity.

Example 4 ITO was patterned into an electrode pattern as shown in FIG.

The pigment colloidal water film was formed on this electrode by the following method to prepare a color filter.

(1) A black positive resist was applied on the entire surface of this substrate, prebaked at 90 ° C., and then exposed and developed using a mask having the pattern of FIG. 4 on this substrate.

(2) Using the substrate after development, electrolysis was performed in the following pigment colloid aqueous solution.

Monochlorocopper phthalocyanine 20 mM (blue pigment) Ferrocenyl PEG 1 mM LiBr (supporting salt) 0.1 M Specifically, in a pigment colloid aqueous solution, ITO of the substrate was used.
The electrode was brought into contact with the + electrode, a stainless steel substrate was used as the cathode, and electrolysis was performed at a constant potential of +0.4 V for 10 minutes. As a result, a blue film was formed on the substrate except where it was masked by the black resist.

(3) Firing at 90 degrees Celsius for 10 minutes.

(4) Next, exposure and development were carried out in the same manner as in (1). At this time, the mask has the pattern of FIG.
A mask that was slid horizontally for the pixels was used.

(5) In the same manner as in (2), a red film was formed as the second color. At this time, the following composition was used as the pigment colloid aqueous solution.

Dianthraquinolyl red 20 mM (red pigment) Ferrocenyl PEG 2 mM LiBr (supporting salt) 0.1 M Specifically, in the aqueous solution of the pigment colloid, the substrate I
The TO electrode was brought into contact with the + electrode, a stainless steel substrate was used as the cathode, and electrolysis was performed at a constant potential of +0.9 V for 30 minutes. As a result, a red film was formed on the substrate where it was masked with the black resist and in addition to the blue film portion.

(6) Firing at 90 ° C. for 10 minutes.

(7) Next, exposure and development were carried out in the same manner as in (4). At this time, as the mask, a mask in which the pattern of FIG. 4 was further slid laterally by one pixel was used.

(8) In the same manner as (5), a green film was formed as a third color film. At this time, the following composition was used as the pigment colloid aqueous solution.

Brominated copper phthalocyanine chloride 20 mM (green pigment) Ferrocenyl PEG 1.5 mM LiBr (supporting salt) 0.1 M Specifically, in the aqueous pigment colloid solution, the substrate I
The TO electrode was brought into contact with the + electrode, a stainless steel substrate was used as the cathode, and electrolysis was carried out at a constant potential of +0.5 V for 15 minutes. As a result, a green film was formed on the substrate where it was masked by the black resist and in addition to the blue and red film portions.

(9) Firing at 100 degrees Celsius for 30 minutes.

With the above procedure, a color filter having three colors of RGB could be formed. Further, the black resist used as the patterning resist could be used as it was as the black matrix.

(Example 5) Using the color filter prepared in Example 1, an active matrix type M
An IM type liquid crystal panel was produced. As a result, it was possible to obtain the same performance as that on the electrode by using the electrode underlaying structure as shown in FIG. 2, and it was possible to fabricate a panel having a higher resolution than the conventional one due to the mosaic pattern.

(Example 6) Using the color filter prepared in Example 2, an active matrix type T
An FT type liquid crystal panel was produced. As a result, it was found that the color filter of the present invention can also be used in a TFT panel.

(Example 7) Using the color filter prepared in Example 3, an active matrix type M
An IM type liquid crystal panel was produced. As a result, it was possible to obtain the same performance as that on the electrode by using the electrode underlaying structure as shown in FIG.

(Embodiment 8) Using the color filter prepared in Embodiment 4, an active matrix type M
An IM type liquid crystal panel was produced. As a result, it was possible to obtain the same performance as that on the electrode by using the electrode underlaying structure as shown in FIG.

[0067]

As described above, the color filter manufacturing method of the present invention is used to manufacture the color filter, and when it is used as a color filter for a small liquid crystal panel such as a liquid crystal television, high resolution, It was possible to manufacture a mosaic-shaped color filter required for high image quality, and it was possible to manufacture a panel with high resolution and high image quality as compared with a conventional liquid crystal panel using a stripe-shaped color filter. Moreover, by taking advantage of the features of the thin film forming method used in the manufacturing method of this color filter, low cost, high yield,
It goes without saying that the image quality is high.

[Brief description of drawings]

FIG. 1 is a mosaic color filter pattern diagram produced by the present invention.

FIG. 2 is a sectional view of a liquid crystal panel having an electrode underlay structure using the color filter of the present invention.

FIG. 3 is an ITO electrode pattern diagram for forming a pigment film used in Examples.

FIG. 4 is a photomask diagram for producing a color filter used in Examples.

FIG. 5 is a color filter diagram having a conventional stripe pattern.

[Explanation of symbols]

 1 Color Filter Substrate 2 Color Filter Side Electrode 3 Pigment Thin Film 4 Overcoat Resin Layer 5 Liquid Crystal Layer 6 Counter Substrate Side Electrode 7 Counter Substrate 8 Sealing Material 9 Light Transmitting Section 10 Light Shading Section

Claims (5)

[Claims] 1. A micellar colloid aqueous solution of a pigment in which pigment particles which are insoluble or sparingly soluble in water, a surfactant and a supporting electrolyte which are charged by an electric field are used as basic components, and the pigment particles are surrounded by the surfactant are prepared, In the method for manufacturing a color filter in which the micelles are destroyed by electrolysis to deposit pigment particles on a conductor to form a pigment thin film, a) electrolysis is performed to have a predetermined striped pattern for forming the thin film. A first step for forming an electrode on a transparent substrate, b) applying a positive resist to the entire surface of the substrate on which the electrode is formed, and c) forming an electrode exposed surface of an arbitrary pattern by exposure and development. The second step, d) the third step of developing the resist in the second step and forming the pigment film of the first color on the exposed electrode pattern by the thin film forming method, e) the first step A fourth step of forming a second-color pigment film by using the thin film forming method by repeating the above step c) d) in a portion other than the portion where the second-eye pigment film is formed, f) first-color and second-color In a portion other than the portion where the pigment film of 1) is formed, the above step c) d) is repeated to form a third color pigment film by using the thin film forming method, g) a transparent conductive layer is formed on the entire surface. A method for producing a color filter, which comprises a sixth step of forming, and h) a seventh step of removing the resist. 2. The method for manufacturing a color filter according to claim 1, wherein a) a first electrode for electrolyzing to form a thin film and having an electrode having a predetermined stripe pattern is formed on a transparent substrate. Step, b) applying a positive resist or a negative resist on the entire surface of the substrate on which the electrode is formed, and c) a second step of forming an electrode exposed surface of an arbitrary pattern by exposure and development, d) a second step Then, the step of developing the resist to form a pigment film of the first color on the exposed electrode pattern using the thin film forming method, e) the third step of removing the resist after step d), f) By repeating steps b) c) d) e), a fourth step of forming a second color in a portion other than the portion where the pigment film of the first color is formed, and g) repeating steps b) c) d). , First and second color pigment film In a portion other than the formed portion, a fifth step of forming a third color, h) a sixth step of forming a transparent conductive layer on the entire surface, and i) a seventh step of peeling the resist , A method for manufacturing a color filter. 3. The method for producing a color filter according to claim 2, wherein a black resist is used as a resist used when forming a pattern for forming the third color in step g). Filter manufacturing method. 4. A micellar colloid aqueous solution of a pigment in which water-insoluble or sparingly soluble pigment particles, a surfactant and a supporting electrolyte that are charged by an electric field are used as basic components, and the pigment particles are surrounded by the surfactant are prepared, In the method of manufacturing a color filter, in which the micelles are destroyed by electrolysis to deposit pigment particles on a conductor to form a pigment thin film, a) an electrode having a predetermined pattern for electrolysis to form a thin film is formed. First step for forming on a transparent substrate, b) A positive type black resist in which a dye or a pigment is dispersed or dissolved is coated on the entire surface of the substrate on which the electrode is formed, and c) an arbitrary pattern by exposure and development. Is formed on the electrode by the second step, d) In the second step, a pigment film of the first color is formed on the electrode pattern on which the resist is developed by using the thin film forming method. The third step of forming, e) the fourth step of forming the second color pigment film by using the thin film forming method by repeating the above steps c) d) in a portion other than the portion where the first color pigment film is formed. Step f) In the portion other than the formation of the first and second color pigment films, the above step c) d) is repeated to form a third color pigment film using the thin film forming method. Step g) A sixth step of forming a transparent conductive layer on the entire surface, h) Then, the black resist is used as it is as a black matrix, a method for producing a color filter. 5. The method for manufacturing a color filter according to claim 4, wherein the step of forming the transparent conductive layer in the sixth step g) is omitted.