JP3191430B2 - Manufacturing method of color filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention is a color liquid crystal television BACKGROUND OF relates to a process for the preparation of suitable color filter in a color liquid crystal display device of the color liquid crystal display and the like for computers.

2. Description of the Related Art In a color filter, between each pixel on a transparent substrate and adjacent to the outside of a colored pattern portion,
It is preferable to form a light shielding portion and a frame light shielding portion, respectively. The light-shielding portion is provided to improve display quality and color contrast by preventing light from leaking from the pixel gap between the color filters, and the frame light-shielding portion is provided for light from the edge of the screen when the cells are assembled. This is provided to prevent leakage and provide a clear image (for example, Japanese Patent Application Laid-Open No. 2-193184). The light shielding portion provided between the pixels of the color filter is usually formed by etching a metal chromium vapor deposition film or a sputtering film. At this time, it is essential to form the chromium film uniformly and without defects such as pinholes, and for patterning, processing such as resist application, exposure, development, baking, etching, and resist peeling is required. In addition, a method has been proposed in which a photosensitive resist material is coated with an ink or paste colored with a black pigment using a printing method, a spinner, a roll coater, or the like, and patterned by mask exposure. It is difficult to achieve sex. Compared with these conventional methods, the backside exposure method is considered to be superior in dimensional accuracy and flatness, and is therefore promising (see, for example,
-138530, JP-A-3-209203, JP-A-3-284704, etc.). That is,
In the backside exposure method, pixels are formed in advance, a negative-type photosensitive coloring paste (a negative-type photosensitive black paste) in which a black pigment is dispersed is applied over the pixels, and then each pixel is used as a mask to form a transparent substrate. This is a method in which a light-shielding portion is formed in a gap between each pixel by exposing from the back surface. At this time, a frame processing mask is used to form a frame light-shielding portion (light-shielding frame) adjacent to the outside of the colored pattern portion including the pixels and the light-shielding portion. The frame processing mask is a mask that transmits light only to the center,
That is, the mask allows light to pass only through the central colored pattern portion and the frame portion having a predetermined width outside the central colored pattern portion. However, there is hardly any one having a light-shielding portion and a frame light-shielding portion that simultaneously satisfy all the characteristics such as light-shielding properties, exposure sensitivity, and pattern edge cutoff. That is, in order to make the light-shielding property sufficient, it is sufficient to increase the thickness of the coating film or increase the coloring component in the paste. However, in this case, the exposure sensitivity decreases, and the required film thickness and light-shielding light-shielding property are reduced. No part can be formed. In addition, at the time of backside exposure, the mask and the glass cannot be brought into close contact with each other due to problems such as mask contamination, and further, since exposure is performed through glass having a thickness of about 1 mm, the outside of the frame light-shielding portion is poorly cut, You can't do sharp things. If the top coat, ITO film formation and ITO patterning are performed in such a state, especially S
In the case of a TN color filter or the like, there is a problem that a projection occurs outside the frame light-shielding portion or an ITO disconnection occurs.

SUMMARY OF THE INVENTION It is an object of the present invention has been made in view of the various shortcomings of the prior art, it is an object of the method for producing a color filter having a cut good frame light shielding portion of the pattern edge Is to provide.

The present invention solves such a problem.
To solve the problem, the following means are adopted. Sand
The method for producing a color filter of the present invention comprises the following (A)
It is characterized in including the step of ~ (C). (A) a step of forming a colored pattern portion having pixels of a plurality of colors and a gap for a light-shielding portion at a predetermined position on the center of the transparent substrate; and (B) a predetermined position on the periphery of the colored pattern portion on the transparent substrate. Forming a resin outer frame at a predetermined interval, and (C) applying a negative type photosensitive black paste on at least the entire surface inside the outer frame on the transparent substrate, and then from the back surface of the transparent substrate. Selectively exposing and subsequently developing and removing the unexposed portion of the paste to form a light-shielding portion between each of the pixels and between the colored pattern portion and the outer frame. Hereinafter, the present invention will be described in detail. The transparent substrate in the present invention is not particularly limited, but glass or transparent plastic is preferably used. The color filter in the present invention has a pattern composed of pixels of a plurality of colors at a predetermined position on the center side on the transparent substrate. The color of each pixel is usually
Red, blue, and green, and the shape of each pixel is not particularly limited, but is generally a stripe shape, a mosaic shape, or the like. In addition, there is usually 10 pixels between each pixel.
A space of about 20 μm is provided, and a light shielding portion is formed in this space. The color filter according to the present invention has a light-shielding portion between the pixels, and has a frame light-shielding portion adjacent to the outside of the colored pattern portion including the pixel pattern and the light-shielding portion. As the width of the frame light shielding part,
Usually, it is about 1 to 5 mm. If the width is too small, light from the backlight is likely to leak, and the display quality may be degraded. If it is too wide, there is no particular problem. However, when the liquid crystal cell is assembled, it is meaningless to protrude outside. It is preferable that the color filter of the present invention further has a resin outer frame adjacent to the outside of the frame light-shielding portion, whereby the peripheral portion of the frame light-shielding portion can be formed in a sharp shape. As the resin used for the outer frame,
It may be a coloring composition similar to that used for a coloring pattern of red, blue, green or the like, or may be a completely different coloring resin. Specifically, phthalocyanine-based, azirake-based, condensed azo-based, quinacridone-based, anthraquinone-based, perinone-based, organic pigments such as perylene-based, inorganic pigments, dyes, ultraviolet absorbers, epoxy resins, acrylic resins, A coloring paste added to a polyimide resin, a urethane resin, a polyester resin, a polyvinyl alcohol resin, an animal protein resin, or the like can be used. The width of the outer frame is not particularly limited, but a range of 0.1 to 20 mm is appropriate. If it is too narrow, patterning tends to be difficult, and if it is too wide, the liquid crystal cell may protrude outward when assembled, which is not preferable. Further, the thickness of the outer frame is preferably made equal to the thickness of the frame light-shielding portion in order to obtain a color filter with good flatness. The color filter according to the present invention may include a top coat, an ITO film, an I
TO patterning can be performed by a known method. The present invention relates to a color filter,
Color fill with frame light-shielding part with sharp edge
It is not intended to provide a method for manufacturing the data. That is,
The method for producing a color filter of the present invention includes the following (A) to (A).
It is important to manufacture in a process including the process (C). (A) Pixels of a plurality of colors are provided at predetermined positions on the center side on a transparent substrate.
A process for forming a colored pattern part with a gap for a light shielding part
Extent, (B) peripheral side predetermined position of the color pattern portion on the transparent substrate
Forming a resin outer frame at predetermined intervals, (C) forming at least an inner side of the outer frame on the transparent substrate.
After applying the negative type photosensitive black paste on the entire surface,
Serial selectively exposed from the rear surface of the transparent substrate, one Zui by the Bae
By developing and removing the unexposed part of the
The gap between pixels, and the color pattern portion and the outer frame
A step of forming a light shielding portion between them. Next, a manufacturing method of that, will be described in detail. For a color filter according to the present invention, on a transparent substrate, (A) the pixel, (B) an outer frame, it is (C) for light shielding part and the frame light-shielding portion, a method of forming in order of use. In this order, in order to improve workability and the like, it is preferable to simultaneously form the outer frame with the same composition as any of red, blue, and green at the time of pixel formation. A method of forming (A) a pixel, (B) an outer frame, (C) a light-shielding portion and a frame light-shielding portion on a transparent substrate in this order will be described below. First, the step (A) will be described. That is,
A colored pattern portion having pixels of a plurality of colors and a gap for a light shielding portion is formed at a predetermined position on the center of the transparent substrate. Known methods such as a photolithography method, a photosensitive paste method, a printing method, an electrodeposition method, and a dyeing method are used for forming each pixel. next,
In the step (B), an outer frame made of resin is formed at a predetermined position on the peripheral side of the transparent substrate at a predetermined interval from the colored pattern portion. That is, finally, the frame light-shielding portion is formed so as to be interposed between the colored pattern portion and the outer frame. Therefore, the space corresponding to the frame light-shielding portion is provided between the outer frame and the colored pattern portion. Just leave it open. Examples of the method for forming the outer frame include a photolithography method, a photosensitive paste method, a printing method,
Known methods such as an electrodeposition method and a dyeing method can be used. Take
(A) The pixel and (B) the outer frame may be formed simultaneously.
For example, the case of using the photosensitive paste method is one example.
You . First, a coloring paste in which the above-described organic pigment or the like is dispersed is applied on a transparent substrate. Examples of the coating method include a known method using a spinner, a roll coater, a die coater, or the like. As the coating film thickness, the film thickness after drying is preferably about 1 to 2 μm. After the application, the substrate on which the coloring paste is applied is dried. The drying temperature is not particularly limited and varies depending on the solvent and the like, but is preferably in the range of 80 to 120 ° C. Next, exposure is performed using a negative type mask such as a stripe shape or a mosaic shape. Ultraviolet rays are generally used as light rays used for exposure. After the exposure, development is performed. By performing the development, the unexposed portions are removed, and a resin outer frame having a predetermined width is formed at a predetermined position on the peripheral side on the transparent substrate. The development can be performed by a known method such as immersion in a developer, rinsing, ultrasonic cleaning, and drying. When immersed in a developing solution, an aqueous solution of an inorganic alkali such as sodium carbonate, sodium hydroxide or potassium hydroxide, or an aqueous solution of an organic alkali such as ethanolamine is preferably used. At this time, the outer frame is coated with a pigment to reduce the ultraviolet transmittance so that a part of the negative-type photosensitive black paste applied to the upper portion of the outer frame at the time of exposure described later is not exposed and remains. And a dye or the like is preferably added. Next, step (C)
Thus, a light shielding portion and a frame light shielding portion are formed. That is, the negative photosensitive black paste is applied to the entire surface of the substrate at least inside the outer frame. As the negative type photosensitive black paste, a monomer having an ethylenically unsaturated bond,
Oligomers, polymers, and a photosensitive composition containing, as a main component, an initiator that generates radicals by ultraviolet light, an inorganic pigment,
Coloring components such as organic pigments, carbon black, dyes, etc. Dispersing coloring components in UV inks, UV curable paints, and photosensitive polyamic acid solutions (“Photo Nice” manufactured by Toray Industries, Inc.) , Black paste "Color Mosaic" BK for color filters (Fuji Hunt Co., Ltd.)
And the like. As a method for applying the negative type photosensitive black paste, a known method using a spinner, a roll coater, or the like can be used. Next, exposure is performed from the back surface of the transparent substrate. At this time, the coloring pattern acts as a kind of mask. At this time, a frame processing mask can be used to form the frame light-shielding portion. As the frame processing mask, it is possible to use a mask that transmits light only to the central colored pattern portion and a frame forming portion having a predetermined width outside the central colored pattern portion, and does not transmit light to portions outside the central colored pattern portion. That is, when the outer frame is not formed, the boundary between the light transmitting portion and the light shielding portion is determined by the shape of the peripheral portion of the frame light shielding portion after development, so that the pattern edge outside the frame light shielding portion often becomes poorly cut. Also, after ITO patterning, protrusions and ITO disconnections occurred outside the frame light-shielding portion. In the present invention, since the outer frame is formed in advance, the boundary between the light transmitting portion and the light shielding portion may be anywhere on the outer frame. Therefore, there is an advantage that the alignment of the mask is simplified, and the peripheral portion of the frame light-shielding portion can be surely finished in a sharp shape. Ultraviolet rays are generally used as light rays used for exposure. After the exposure, development is performed. For development, a method using a developer such as an organic solvent or an aqueous alkali solution is generally used. By developing
The unexposed portions dissolve, only the exposed portions remain on the transparent substrate, and a light-shielding portion is formed between the pixels, and a frame light-shielding portion is formed between the colored pattern portion and the outer frame, adjacent to both. Thereafter, if necessary, a top coat, ITO film formation, and ITO patterning can be performed by a known method.

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples. The flatness was checked with a stylus-type surface meter, and the presence or absence of disconnection of ITO was checked with an electric conductivity meter. Example 1 N-methylpyrrolidone solution of polyamic acid (25 wt.
%) To prepare colored pastes in which red, green, and blue organic pigments are dispersed. Each of these colored pastes was applied on a glass substrate by a spinner, and a pattern was formed by an etching method using a positive resist. For the third color, pixels and an outer frame were simultaneously formed using a mask that formed an outer frame having a thickness of 5 mm at an interval of 3 mm on the peripheral side of the colored pattern portion. Through the above steps, a colored pattern portion including red, green, and blue pixels and a gap for a light-shielding portion is formed at the central portion on the glass substrate, and an outer frame is formed on the upper peripheral portion of the substrate at a distance of 3 mm from the colored pattern portion. Was formed. The thickness of each of the pixel and the outer frame is 1.5 μm
Met. Separately, 30 wt% of carbon black and phthalocyanine blue were added to a photosensitive polyamic acid solution ("Photo Nice" manufactured by Toray Industries, Inc.) at a ratio of 3: 7, and the mixture was dispersed in a bead mill to prepare a paste for a light shielding portion. This paste was applied to the entire surface of the substrate on which the pattern was formed using a spinner.
Next, from the glass surface side of the substrate, the substrate was exposed to light with a chemical lamp at a light amount of 100 mJ / cm2 through a negative mask having a boundary between a light transmitting portion and a light shielding portion on the outer frame, and developed with an N-methylpyrrolidone solution. Post-baking was performed at 300 ° C. for 1 hour to obtain a light-shielding portion and a frame light-shielding portion. Then,
N-methylpyrrolidone solution of polyamic acid (25 wt.
%) Was applied as a top coat to 1.2 μm, followed by I
TO was formed by sputtering at 250 ° C. These ITOs were patterned by an etching method using a positive resist. As a result, the flatness was good, and there was no disconnection of ITO at ± 0.05 μm. Comparative Example 1 In Example 1, a colored pattern was formed without forming an outer frame at the time of forming the third color pattern, and the other steps were performed in exactly the same manner as described above, and the paste for the light shielding portion was exposed, exposed, and developed.
As a result of ITO film formation and patterning, the edge of the frame light-shielding portion was poorly cut and the flatness was poor at ± 2.0 μm. In addition, ITO disconnection occurred frequently at the end of the frame light-shielding portion.

The present invention has been configured as described above.
The edge of the pattern outside the light-shielding portion of the frame is good, and ITO
After patterning, protrusions outside the frame light-shielding part, ITO
Disconnection can be prevented.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-193184 (JP, A) JP-A-4-93825 (JP, U) JP-A-3-49532 (JP, U) (58) Investigation Field (Int.Cl. ⁷ , DB name) G02B 5/20 101

Claims (1)

(57) [Claims] 1. A method for manufacturing a color filter, comprising the following steps (A) to (C). (A) a step of forming a colored pattern portion having pixels of a plurality of colors and a gap for a light-shielding portion at a predetermined position on the center of the transparent substrate; and (B) a predetermined position on the periphery of the colored pattern portion on the transparent substrate. Forming a resin outer frame at a predetermined interval, and (C) applying a negative type photosensitive black paste on at least the entire surface inside the outer frame on the transparent substrate, and then from the back surface of the transparent substrate. Selectively exposing and subsequently developing and removing the unexposed portion of the paste to form a light-shielding portion between each of the pixels and between the colored pattern portion and the outer frame.