JP2003043238A - Color filter and method for manufacturing the same, liquid crystal element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent coloring nonuniformity among colored parts in a row of the colored parts from being generated in a method for manufacturing a color filter where the colored parts are formed by imparting curable ink to the opening parts of a black matrix made of a plastic resin. SOLUTION: Recessed parts are formed on the upper surface of the black matrix in regions separating the mutually adjoining opening parts in the row direction. The curable ink is continuously applied along the row direction. Thereby the applied curable ink is made to be a stripe-shaped continuous layer. By curing the ink in this state, the coloring parts are formed on each of the opening parts with a uniform film thickness.

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 a constituent member of a color liquid crystal display used in a color television, a personal computer, a pachinko game table, etc., a manufacturing method thereof, and a liquid crystal using the color filter. Regarding the device.

[0002]

2. Description of the Related Art In recent years, the development of personal computers,
In particular, with the development of portable personal computers, the demand for liquid crystal displays, especially color liquid crystal displays, has increased. However, for further widespread use, a significant cost reduction is required, and in particular, cost reduction of the color filter, which has a large specific gravity in cost, is required.

Conventionally, various methods have been tried to meet the above-mentioned requirements while satisfying the required characteristics of the color filter, but a method satisfying all the required characteristics has not been established yet. Each method will be described below.

The first method is a dyeing method. The dyeing method is as follows. First, a water-soluble polymer material, which is a material for dyeing, is formed on a glass substrate, this is patterned into a desired shape by a photolithography process, and then the obtained pattern is immersed in a dyeing bath. Get a colored pattern. By repeating this three times, each colored portion of R (red), G (green), and B (blue) is formed.

The second method is a pigment dispersion method, which is recently replacing the dyeing method. In this method, a photosensitive resin layer in which a pigment is dispersed is first formed on a substrate, and this is patterned to obtain a monochrome pattern. Further, by repeating this process three times, each colored portion of R, G and B is formed.

The third method is an electrodeposition method. This method
First, the transparent electrode is patterned on the substrate, and the pigment, resin,
The first colored portion is electrodeposited by immersing it in an electrodeposition coating solution containing an electrolytic solution or the like. This process is repeated three times to form R, G, and B colored portions.

The fourth method is to disperse a thermosetting resin pigment and repeat printing three times to obtain R, G, and
After being separately coated on B, the resin is cured to form a colored portion.

In either method, it is general to form a protective layer on the colored portion. In addition, what is common to these methods is that in order to form the colored portions of three colors of R, G, and B, it is necessary to repeat the same process three times, which results in high cost. In addition, there is a problem that the yield is reduced due to the large number of steps.

[0009]

In order to solve these problems, a method for producing a color filter using an ink jet method is disclosed in JP-A-59-75205 and JP-A-6-75205.
There are proposals disclosed in JP-A-3-235901, JP-A-1-217320, etc., but they are still insufficient.

Particularly, in the method of manufacturing a color filter by the ink jet method, color mixing between adjacent colored portions of different colors becomes a problem. Therefore, as a method for preventing color mixing between the colored portions of the color filter, Japanese Patent Laid-Open No.
There is a proposal disclosed in Japanese Patent No. 123005. In this method, a pattern of silicone rubber having high water repellency and oil repellency is formed on the light shielding layer to prevent color mixture in the inkjet method or the printing method. Further, as a method for obtaining a light-shielding layer having a water-repellent and oil-repellent surface by a simpler method, there is a proposal disclosed in JP-A-7-35916. In this proposal, a light-transmissive photosensitive resin layer containing silicone particles is formed on a light-shielding layer forming member, the photosensitive resin layer is patterned by a photolithography process, and then the patterned photosensitive resin layer is formed. This is a method of processing the light shielding layer forming member as a mask.

However, when the above-mentioned proposed light-shielding layer is used and a color filter in which colored portions of the same color are arranged in a stripe pattern is formed by an ink jet method, the following problems occur.

When ink is applied along each line of a so-called black matrix, which is a light-shielding layer having openings arranged in a plurality of rows and a plurality of columns, ink is continuously applied to the upper surface of the black matrix which separates adjacent openings. When applied, the ink droplet that has landed on the black matrix is repelled on the surface of the black matrix and drawn into the opening.
At this time, the ratio of the amount of ink flowing into each of the two openings is not clear, and the amount of applied ink is different in the colored portions of the same color in each row, resulting in uneven coloring. In addition, even if ink is intermittently applied only to each opening so that the ink drops do not get on the black matrix, the same applies when a slight difference occurs in the ejection amount or the landing position for each ejection of the ink. In addition, there is a difference in the amount of ink applied between the same-colored landing portions in each row, resulting in uneven coloring.

An object of the present invention is to solve the above problems, to manufacture a color filter with a good yield by an ink jet system without causing coloring unevenness in a simple process, and to use the color filter to inexpensively display a color liquid crystal. It is to provide an element.

[0014]

A first aspect of the present invention is a method for producing a color filter having at least a resin black matrix and a colored portion formed in an opening of the black matrix on a transparent substrate. A step of forming a black matrix having openings in a plurality of rows and a plurality of columns on a transparent substrate, and a step of applying a curable ink to at least the openings of the black matrix by an inkjet method and curing the ink to form a colored portion. And a concave portion on the upper surface of a region that separates adjacent openings in the row direction of the black matrix, and curable ink of the same color is continuously provided across the black matrix along the row direction. It is a manufacturing method of a color filter characterized by applying.

The above-described method for manufacturing a color filter of the present invention includes the following configuration as a preferred embodiment.

The black matrix is formed by forming a photosensitive black resin layer on a transparent substrate, performing pattern exposure and developing. Further, the photosensitivity of the black resin layer is positive, and the pattern exposure is performed simultaneously from the surface side of the black resin layer by changing the exposure amount of the opening forming region of the black matrix and the recess forming region of the upper surface of the black matrix, or The black resin layer has a negative photosensitivity, and in the black matrix forming region, the pattern exposure is performed simultaneously from the back surface side of the transparent substrate by changing the exposure amount between the recess forming region and the region other than the recess forming region.

A non-photosensitive black resin layer is formed on a transparent substrate, a photoresist layer is formed on the black resin layer, and after pattern exposure and development, the black resin layer is formed using the resist pattern as a mask. The opening is formed by patterning by etching, and the photoresist pattern is further patterned to form the recess. Particularly, the photosensitivity of the resist is positive, and after the black resin layer is etched, pattern exposure is performed again and development is performed to form the above-mentioned concave portion in the central portion.

A second aspect of the present invention comprises at least a resin black matrix having openings in a plurality of rows and a plurality of columns on a transparent substrate, and a colored portion formed in the openings, and the color filter of the present invention described above. The color filter is manufactured by the manufacturing method described in 1., and preferably has a protective layer on the colored portion.

A third aspect of the present invention is a liquid crystal device characterized in that a liquid crystal is sandwiched between a pair of substrates, and one of the substrates is constructed by using the color filter of the present invention.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, by forming a concave portion on the upper surface of the black matrix in a region separating adjacent openings in the ink applying direction, the ink applied on the black matrix is formed into the concave portion. Held in
The ink droplets landed in this direction are continuous. Therefore, a uniform film thickness is obtained in the colored portion obtained by curing the ink, and uneven coloring is prevented. Further, even when there is a change in the ink ejection amount or a deviation in the landing position, it is eliminated by the continuous ink droplets, and the occurrence of uneven coloring due to these is also prevented.

FIG. 1 schematically shows the structure of the color filter of the present invention. In the figure, (a) is a schematic plan view, (b) is a schematic sectional view taken along the line AA ′, 1 is a black matrix, 2 is an opening of the black matrix 1, 3 is a colored part,
Reference numeral 4 is a concave portion of the black matrix 1, and 5 is a transparent substrate.

As shown in FIG. 1, the colored portion 3 is formed in the opening of the black matrix 1. In the present invention, when forming the colored portion 3, the black matrix 1
The recesses 4 are formed in the regions separating the openings 3 adjacent to each other in the row direction in which the colored portions 3 of the same color are formed (vertical direction on the paper surface), and ink is continuously applied along the row direction. To do. Therefore, although the ink droplets also land on the black matrix 1, the recesses 4 serve as storage portions, and the ink droplets are continuously held in a stripe shape in the row direction. still,
Between the openings adjacent to each other in the column direction (the left-right direction on the paper surface), since the concave portion is not formed on the upper surface of the black matrix 1, the ink is repelled well, and the inks of different colors are not mixed with each other. .

In the present invention, the method of forming the black matrix 1 having the above-mentioned concave portions 4 is not particularly limited, but a method of forming the black matrix 1 with a photosensitive black resin and a non-photosensitive black resin and a resist are used. A preferable method is to form the film. Hereinafter, the method for manufacturing the color filter of the present invention will be described in detail with reference to respective preferred embodiments.

FIG. 2 is a process chart of a preferred embodiment of the color filter manufacturing method of the present invention, which is an example in which the black matrix 1 is formed of a photosensitive black resin. In the figure,
21 is a photosensitive black resin layer, 22 is a photomask, and 23
Reference numerals a and 23b are light transmitting regions of the photomask 22, 24 is a curable ink, and 25 is a protective layer. The same members as those in FIG. 1 are designated by the same reference numerals. Hereinafter, each step will be described. The steps (a) to (f) in FIG.
2 is a schematic cross-sectional view corresponding to, and corresponds to an AA ′ cross section of FIG. 1.

Step (a) The photosensitive black resin layer 21 is formed on the transparent substrate 5. A glass substrate is generally used as the transparent substrate 5,
If it has transparency and strength as a color filter,
A plastic substrate such as polyethylene terephthalate or polycarbonate can also be used. Further, if necessary, the surface of the transparent substrate 5 may be subjected to a treatment for enhancing the adhesiveness with the black matrix 1 and the colored portion 3.

The photosensitive black resin layer 21 used in this embodiment may be a negative type or a positive type, and may be a black pigment or dye, a photosensitive resin material, and other non-photosensitive materials. It is formed by dissolving or dispersing a resin material in a suitable solvent and applying it on the transparent substrate 5. As the black pigment, carbon black, acetylene black, iron black, aniline black, cyanine black or the like is used, and as the black dye, an azoic type disperse dye or the like can be used, but cyan, magenta, and yellow pigments Alternatively, it may be black by mixing a dye. In addition, the transparent substrate 5
As the coating method on the top, spin coating, die coating,
Various methods such as dip coating and spray coating can be used, and the coating film is formed with a thickness of about 1 μm in consideration of the light shielding property. Further, the coating film is subjected to a drying treatment with a hot plate or the like, if necessary.

Step (b) The photosensitive black resin layer 21 is pattern-exposed using an exposure device having a wavelength matching the sensitivity of the photosensitive black resin layer 21 and a photomask 22 having a predetermined pattern. Figure 2
The case where the photosensitive black resin layer 21 is a positive type is shown, and the light transmission regions 23a corresponding to the opening 2 forming region and the concave 4 forming region of the black matrix 1 are exposed so as to be exposed, respectively.
The photomask 22 having 23b is used, and the light transmitting region 23a is set so that the amount of transmitted light is smaller than that of the light transmitting region 23b. Such a photomask 22
By exposing from the surface side of the photosensitive black resin layer 21 through the, the unexposed black resin is left in the region where the concave portion 4 is formed after development, depending on the exposure amount. That is, the patterning of the opening 2 and the patterning of the recess 4 can be performed simultaneously.

When the photosensitive black resin layer 21 is a negative type, since the exposed area is cured and remains, the opening 2 forming area is completely shielded from light and a light transmitting area corresponding to the concave 4 forming area is formed. By exposing from the back surface of the transparent substrate 5 using a photomask having a light transmission area corresponding to the black matrix 1 formation area other than the depression 4 formation area and set so that the amount of transmitted light of the former is smaller than that of the latter. Good.

Step (c) The photosensitive black resin layer 21 after exposure is developed with an appropriate developing solution and post-baked to obtain a black matrix 1 having openings 2 and recesses 4.

The patterning of the opening 2 and the patterning of the recess 4 may be performed separately.

Step (d) A curable ink 24 is continuously applied in the row direction (left and right direction on the paper) across the black matrix 1 from an inkjet head (not shown). Since the volume of the curable ink 24 is significantly reduced after curing, the curable ink 24 is usually applied in an amount larger than the volume of the opening 2. Therefore, the ink droplets that have landed in the openings 2 are repelled by the surface of the black matrix 1 and thus a convex meniscus is formed by the surface tension. However, in the present invention, the openings 2 and the recesses 4 are very large. Since they are close to each other, the ink droplets that have landed on each other are connected to form a continuous layer. As a result, even if the landing position of the ink is displaced or the ejection amount is changed, the thickness of the ink layer in each opening 2 becomes uniform due to the movement of the ink, so that the ink is cured in the subsequent step. Then, the colored portion 3 having a uniform film thickness is obtained.

Curable ink 2 used in the present invention
As No. 4, since it becomes the colored part 3 in the end, it contains a binder component and a colorant which are cured by heat treatment or light irradiation, and is used after being dissolved or dispersed in an appropriate solvent. Examples of such a binder component include acrylate derivatives and methacrylate derivatives. The colorant may be either a dye type or a pigment type, and the solvent may contain pure water (ion-exchanged water) as a main component and a hydrophilic organic solvent or the like.

The dyes preferably used in the present invention include C.I. I. Acid Red 118, C.I. I. Acid Red 254, C.I. I. Acid Green 25,
C. I. Acid Blue 113, C.I. I. Acid Blue 185, C.I. I. Acid Blue 7 can be mentioned,
It is not limited to these. Examples of the pigment include C.I. I. Pigment Red 177, C.I.
I. Pigment Red 5, C.I. I. Pigment Red 1
2, C.I. I. Pigment Green 36, C.I. I. Pigment Blue 209, C.I. I. Pigment Blue 16 and the like. These dyes or pigments are added to the ink in an amount of 0.
It is preferably used in a proportion of 1 to 20% by weight.

The hydrophilic organic solvent preferably used as a component of the curable ink 24 in the present invention includes, for example, alkyl alcohols having 1 to 4 carbon atoms such as methyl alcohol and ethyl alcohol; dimethylformamide and dimethylacetamide. Amides such as acetone; ketones or keto alcohols such as acetone and diacetone alcohols; ethers such as tetrahydrofuran and dioxane; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol, propylene glycol, butylene glycol, thiodiene Alkylene glycols in which the alkylene group such as glycol and diethylene glycol contains 2 to 6 carbon atoms; glycerin; ethylene glycol monomethyl (or ethyl) ether; Lower alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl (or ethyl) ether and triethylene glycol monomethyl (or ethyl) ether; N-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazo Examples include, but are not limited to, ridinone.

The ink jet method used in the present invention is a bubble jet (registered trademark) type using an electrothermal converter as an energy generating element, or
A piezo jet type using a piezoelectric element or the like can be used, and the coloring area and coloring pattern can be set arbitrarily.

Step (e) The curable ink 2 is subjected to necessary treatments such as heat treatment and light irradiation.
4 is cured to form the colored portion 3. At this time, ink 2
4 has a stripe-shaped continuous layer formed across the black matrix 1, so that it is uniformly applied to each opening 2.
The colored portions 3 having a uniform film thickness are formed in each row. still,
The heating temperature during the post-baking of the black matrix 1 in the step (c) is usually about 150 to 250 ° C.,
In the post-baking process, the organic component volatilizes from the black matrix 1 and the transparent substrate 1 exposed in the opening 2 is exposed.
It may adhere to the surface to make it hard to wet the curable ink 24. In such a case, the post-baking process of the black matrix 1 may be performed simultaneously with the curing process of the curable ink 24.

Since the ink hardened in the recess 4 is shielded by the black matrix 1, it does not affect the display.

Step (f) A protective layer 25 is formed on the colored portion 3 if necessary. As the protective layer 25, a resin film of a photo-curing type, a thermo-setting type, or a photo-heat combination type, an inorganic film formed by vapor deposition, sputtering or the like can be used, and it has transparency as a color filter, In the step (1), for example, when forming a liquid crystal element, any material that can withstand the ITO film forming process, the alignment film forming process, etc. can be used.

Next, an embodiment in which the black matrix 1 is formed by using a non-photosensitive black resin and a resist will be described by showing steps in FIG. In the figure, 31 is a non-photosensitive black resin layer, 32 is a photoresist layer, 33 and 36 are photomasks, 34 and 37 are resist patterns, and 35 is a black resin pattern. The same members as those in FIGS. 1 and 2 are designated by the same reference numerals. Hereinafter, each step will be described. (A) to (f) of FIG. 3 are schematic cross-sectional views corresponding to the following steps (a) to (f), and correspond to the AA ′ cross section of FIG. 1.

Step (a) A non-photosensitive black resin layer 31 and a photoresist layer 32 are formed on the transparent substrate 5. The non-photosensitive black resin layer 31 is
The black dye or pigment described in the embodiment of FIG. 2 is mixed with polyimide, acrylic acid monomer, urethane acrylate, etc., and the coating solution dispersed in a suitable solvent is applied on the transparent substrate 5 to have a thickness of 1 μm. Formed to a degree. As the photoresist layer 32, a commercially available negative type or positive type resist can be used.

Step (b) The photoresist layer 32 is pattern-exposed through a photomask having a predetermined pattern to form a resist pattern 34.
To form. In this embodiment, the photoresist layer 32 is a positive type.

Step (c) The non-photosensitive black resin layer 31 is etched by using the resist pattern 34 as a mask to form a black resin pattern 35 having the openings 2.

Step (d) The resist pattern 34 is again pattern-exposed through the photomask 36, and the resist pattern 3 having the concave portions 4 is formed.
Form 7. In this embodiment, the black resin pattern 35 and the resist pattern 37 form the black matrix 1. When the photoresist layer 32 is a negative type, the resist pattern 34 is once removed and then a photoresist is used again to form a resist pattern 37.
Or the resist pattern 37 may be formed on the resist pattern 34 by using a separate photoresist, or the resist pattern 34 may be patterned by etching. In the present invention, since the number of steps is small, the method using the positive photoresist layer 32 is preferably applied as shown in this embodiment.

Step (f) In the same manner as in (d) to (f) of FIG. 2 described above, the curable ink is applied to form the colored portion 3 and the protective layer 25 if necessary, to thereby form the present invention. Get a color filter.

Next, FIG. 4 shows a schematic sectional view of an embodiment of the liquid crystal element of the present invention. The present embodiment is an example in which a TFT type color liquid crystal element is configured using the color filter of the present invention obtained by the process of FIG. In the figure, 40 is a common electrode, 41 is a counter substrate, 42 is a pixel electrode, 43 and 44 are alignment films, and 45 is a liquid crystal. The same members as those in FIG.

In the color liquid crystal element, generally, the substrate 5 on the color filter side and the counter substrate 41 are put together to form a liquid crystal 45.
Is formed by encapsulating. TFTs (not shown) and pixel electrodes 42 are formed in a matrix on the inside of one substrate 41 of the liquid crystal element. In addition, inside the substrate 5 on the color filter side, at a position facing the pixel electrode 42,
The colored portion 3 of the color filter is formed so that R, G, and B are arranged, and the transparent common electrode 40 is formed thereon. Further, alignment films 43 and 44 are formed on the surfaces of both substrates, and liquid crystal molecules are arranged in a fixed direction. These substrates are arranged to face each other via a spacer (not shown), are bonded together by a sealant (not shown), and the liquid crystal 45 is filled in the gap.

In the case of a transmissive liquid crystal device, the substrate 41 and the pixel electrode 42 are formed of a transparent material, a polarizing plate is adhered to the outside of each substrate, and a fluorescent lamp and a scattering plate are generally combined. The display is performed by using a backlight and causing the liquid crystal compound to function as an optical shutter that changes the light transmittance of the backlight. In the case of a reflective type, the substrate 41 or the pixel electrode 42 is formed of a material having a reflective function, or a reflective layer is provided on the substrate 41 and a polarizing plate is provided outside the transparent substrate 5, The display is performed by reflecting the light incident from the filter side.

Needless to say, in the liquid crystal element of the present invention, if the color filter of the present invention is used, the conventional technique can be used as it is for other members.

[0049]

EXAMPLES Example 1 A glass substrate (“1737” manufactured by Corning Incorporated) was ultrasonically cleaned with an alkali using a 2% sodium hydroxide aqueous solution, and then subjected to UV ozone treatment and then containing carbon black. A resist material (manufactured by Nippon Steel Chemical Co., Ltd .; negative-type resist ink for black matrix "V-259 BK739P") was applied by a spin coater to a film thickness of 1 µm. This glass substrate was heated on a hot plate at 80 ° C. for 180 seconds to temporarily cure the resist.

Using a DEEP-UV exposure device ("PLA FA600" manufactured by Canon Inc.), proximity exposure was performed through a mask having a predetermined pattern. The pattern of the mask used was set so that the amount of transmitted light in the recessed region was smaller than that in the surrounding region. continue,
Develop with a developer of an aqueous solution of sodium carbonate and a spin developing machine (manufactured by Takizawa Sangyo Co., Ltd.), and then rinse with pure water,
The developing solution was completely removed to form a black matrix pattern. The obtained black matrix pattern has a recess in a region separating adjacent openings in the row of openings, and the thickness of the black matrix pattern in the recess is 80% of the thickness of the peripheral portion of the recess. It was

Then, using an ink jet recording apparatus,
The curable inks containing the R, G, and B dyes were continuously applied along the opening rows of the black matrix pattern. The ink used was a dye (R: CI Acid Red 118, G: CI Acid Green 25,
B: C.I. I. Acid Blue 113) is dispersed in a resin (self-crosslinking thermosetting resin containing an acrylic-silicone graft polymer as a main component) and dissolved in a solvent (a mixed solvent of ethylene glycol and ion-exchanged water).

Next, heat treatment was carried out at 230 ° C. for 30 minutes to cure the black matrix pattern and the curable ink to form a black matrix and colored portions, and a color filter was obtained. As a result, in each colored portion row, there was no uneven coloring between the colored portions.

Next, a protective layer (manufactured by Nippon Steel Chemical Co., Ltd .; transparent heat-resistant resist "V259P" is formed on the color filter.
A ”), and an ITO film was formed as a transparent conductive film.
All of them had excellent adhesiveness and no trouble occurred. Furthermore, when a liquid crystal element was formed by a conventional method using a color filter formed with an ITO film, it was possible to perform color display with no defect and excellent color characteristics.

Example 2 A black matrix pattern was formed on a glass substrate in the same manner as in Example 1 and heated in a clean oven at 200 ° C. for 40 minutes to form a black matrix.

Then, using an ink jet recording apparatus,
A curable ink containing each of the R, G, and B pigments was continuously applied along the opening row of the black matrix.
The inks used are pigments (R: CI Pigment Red 177, G: CI Pigment Green 36, B:
C. I. Pigment Blue 209) dissolved in ethyl cellosolve, an acrylic copolymer (monomer components: methyl methacrylate, hydroxyethyl methacrylate, N
-Methylol acrylamide, triphenylsulfonyl hexafluoroantimonate) and ethylene glycol and ion-exchanged water were added to improve the ink jet suitability.

Then, heat treatment was carried out at 230 ° C. for 30 minutes to cure the curable ink to form colored portions and obtain a color filter. As a result, in each colored portion row, there was no uneven coloring between the colored portions.

Next, as in Example 1, a protective layer and a transparent conductive film were laminated on the color filter, but both had excellent adhesion and no problems occurred. Furthermore, when a liquid crystal element was constructed in the same manner as in Example 1, it was possible to perform color display with no defects and excellent color characteristics.

(Example 3) Carbon black 4 g, N-
Methyl-2-pyrrolidone 40 g, butyl cellosolve 6 g
Using 100 g of glass beads and a homogenizer at 7,000 rpm for 30 minutes, the glass beads were removed by filtration to obtain a pigment dispersion liquid having a pigment concentration of 8% by weight.

28 g of a polyimide precursor solution was added to and mixed with 30 g of the pigment dispersion liquid to prepare a black paste. Alkali-free glass substrate (20
A polyimide precursor black colored film was formed by spin coating on a 0 mm square and a thickness of 1.1 mm) to a film thickness of 1.0 μm and performing semi-cure at 125 ° C. for 20 minutes. After cooling, a positive photoresist (“M” manufactured by Shipley Co., Ltd.
microposit "RC10030cP),
A photoresist film was formed by heating and drying at 90 ° C. for 20 minutes. This is an ultraviolet exposure machine (Canon KK "PLA
-501F "), and exposed through a photomask. After exposure, alkaline developer (Tokyo Ohka Kogyo Co., Ltd. “N
MD-3 "), developing the photoresist and etching the polyimide precursor black colored film at the same time,
The opening was formed.

Next, the resist pattern is pattern-exposed again through a photomask having a different opening, and development is performed so that the development time is shortened and the black colored film remains, and the adjacent openings in the opening row of the black matrix. A resist pattern having a concave portion was formed in the central portion of the area separating the portions. Then, heat treatment was performed at 280 ° C. for 30 minutes to cure the black colored film to form a black matrix composed of the black colored film and a resist pattern partially having a recess. The thus-obtained black matrix had a film thickness of 1.0 μm in the concave portion and a film thickness up to the upper surface of the resist pattern of 1.22 μm.

Next, using the ink jet recording apparatus, the dye-based curable ink used in Example 1 was continuously applied along the rows of the openings, and was subjected to heat treatment to be cured to obtain a color filter. . In the obtained color filter, there was no uneven coloring between the colored portions in each colored portion row.

Next, as in Example 1, a protective layer and a transparent conductive film were laminated on the color filter, but both had excellent adhesion and no problems occurred. Furthermore, when a liquid crystal element was constructed in the same manner as in Example 1, it was possible to perform color display with no defects and excellent color characteristics.

Example 4 A black colored film at 30 ° C. at 30 ° C.
A color filter was formed in the same manner as in Example 3 except that the curable ink was applied without performing heat treatment for 1 minute, and the black colored film was cured at the same time when the curable ink was cured. In the obtained color filter, there was no uneven coloring between the colored portions in each colored portion row.

Next, as in Example 1, a protective layer and a transparent conductive film were laminated on the color filter, but both had excellent adhesion and no problems occurred. Furthermore, when a liquid crystal element was constructed in the same manner as in Example 1, it was possible to perform color display with no defects and excellent color characteristics.

(Comparative Example 1) A color filter was manufactured in the same manner as in Example 1 except that no recess was formed on the upper surface of the black matrix. As a result, the obtained color filter had uneven coloring between the colored portions within the colored portion rows.

(Comparative Example 2) A color filter was produced in the same manner as in Example 2 except that no recess was formed on the upper surface of the black matrix. As a result, the obtained color filter had uneven coloring between the colored portions within the colored portion rows.

(Comparative Example 3) A color filter was produced in the same manner as in Example 3 except that the step of pattern-exposing the resist pattern again to form the recess was not performed. As a result, the obtained color filter had uneven coloring between the colored portions within the colored portion rows.

(Comparative Example 4) A color filter was produced in the same manner as in Example 4 except that the step of pattern-exposing the resist pattern to form the recesses was not performed. As a result, the obtained color filter had uneven coloring between the colored portions within the colored portion rows.

[0069]

As described above, according to the present invention,
In a method for manufacturing a color filter in which ink is applied to the openings of a black matrix to form colored portions, it is possible to suppress the occurrence of coloring unevenness between the colored portions, and to provide a highly reliable color filter with high yield. Thus, it becomes possible to provide a high-quality color liquid crystal display at a lower cost.

[Brief description of drawings]

FIG. 1 is a schematic view of an embodiment of a color filter of the present invention.

FIG. 2 is a process drawing of an embodiment of a color filter manufacturing method of the present invention.

FIG. 3 is a process drawing of another embodiment of the color filter manufacturing method of the present invention.

FIG. 4 is a schematic sectional view of an embodiment of a liquid crystal element of the present invention.

[Explanation of symbols]

1 Black matrix 2 openings 3 Coloring part 4 recess 5 transparent substrate 21 Photosensitive black resin layer 22 Photomask 23a, 23b Light transmission area 24 curable ink 25 Protective layer 31 Non-photosensitive black resin layer 32 photoresist layer 33, 36 Photomask 34, 37 resist pattern 35 Black resin pattern 40 common electrode 41 Counter substrate 42 pixel electrode 43,44 Alignment film 45 LCD

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G02F 1/1335 505 G03F 7/11 503 2H096 G03F 7/11 503 7/40 521 4J039 7/40 521 B41J 3 / 04 101Z F term (reference) 2C056 FB01 2H025 AB13 AD01 AD03 FA03 FA04 FA17 FA29 FA40 2H042 AA09 AA15 AA26 2H048 BA02 BA11 BA37 BA45 BA48 BA58 BA64 BB02 BB14 BB15 BB15 FB15A02H1026FB12H101 FA02Y1035 FA02H101 FA04Y2 FA04Y2 FA0Y FA02 FA35Y021 EA12 EA16 GA08 HA01 HA17 HA30 JA04 4J039 AD09 AD10 BC07 BC10 BC36 BC50 BC51 BC61 BE01 BE02 BE12 CA06 CA07 EA03 EA05 EA15 EA16 EA19 EA20 GA24

Claims (9)

[Claims] 1. A method of manufacturing a color filter having at least a resin black matrix on a transparent substrate and a colored portion formed in an opening of the black matrix, the method comprising a plurality of rows and a plurality of columns on the transparent substrate. At least a step of forming a black matrix having openings, and a step of applying a curable ink to at least the openings of the black matrix by an inkjet method and curing the ink to form a colored portion. Manufacturing of a color filter characterized by having a recess on the upper surface of a region that separates adjacent openings in the row direction, and continuously applying curable ink of the same color across the black matrix along the row direction. Method. 2. The method for producing a color filter according to claim 1, wherein the black matrix is formed by forming a photosensitive black resin layer on a transparent substrate, performing pattern exposure and developing. 3. The black resin layer has a positive photosensitivity, and pattern exposure is simultaneously performed from the surface side of the black resin layer by changing the exposure amount of the opening forming region of the black matrix and the recess forming region of the upper surface of the black matrix. Item 3. A method of manufacturing a color filter according to item 2. 4. The black resin layer has a negative photosensitivity, and in the black matrix forming region, the exposure amount is changed between the recess forming region and the region other than the recess forming region, and the pattern is simultaneously formed from the rear surface side of the transparent substrate. The method of manufacturing a color filter according to claim 2, which comprises exposing. 5. A non-photosensitive black resin layer is formed on a transparent substrate, a photoresist layer is formed on the black resin layer, and after pattern exposure and development, the black resin is used as a mask with the resist pattern as a mask. The method of manufacturing a color filter according to claim 1, wherein the layer is patterned by etching to form an opening, and the resist pattern is further patterned to form the recess. 6. The method for producing a color filter according to claim 5, wherein the photoresist has a positive photosensitivity, and the recesses are formed by pattern exposure and development again after etching the black resin layer. 7. A resin black matrix having openings in a plurality of rows and a plurality of columns on a transparent substrate, and at least a colored portion formed in the openings, according to claim 1. A color filter manufactured by a method for manufacturing a color filter. 8. The protective layer is provided on the colored portion.
The color filter described in. 9. A liquid crystal element comprising a pair of substrates and a liquid crystal sandwiched between the substrates, one of the substrates comprising the color filter according to claim 7.