JPH10115703A - Method for manufacturing color filter and liquid crystal display device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the display performance as a liquid crystal display element by subjecting the projecting parts on a base material to an ink repulsion treatment under specific conditions. SOLUTION: The colored layers 6 of color filters are formed by spraying and depositing ink to the substrate 1, the projecting parts 2, recessed parts 3 segmented by the projecting parts 2 and the projecting parts 2, the front surfaces 4 of the projecting parts 2, the flanks 5 of the projecting parts 2 and the recessed parts 3. Namely, the projecting parts 2 are formed on the substrate 1 and the ink is sprayed by an ink jet system to the recessed parts 3 segmented by the projecting parts 2, by which the ink is deposited in the recessed parts 3 and the colored layers 6 are formed. The projecting parts 2 are subjected to the ink repulsion treatment so that the upper parts of the projecting parts 2 just before ink spraying are >=90 deg. at the advance contact angle of the ink to be sprayed and that the retreat contact angle is made smaller by >=40 deg. than the advance contact angle. The color filters are formed by spraying ink to the recessed parts 3 segmented by the projecting parts 2. The advance contact angle of the ink is >=100 deg. and the retreat contact angle is preferably smaller by >=50 deg. than the advance contact angle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a color filter by forming a convex portion on a substrate and coloring a concave portion surrounded by the convex portion by an ink jet method, and a liquid crystal display device using the same. .

[0002]

2. Description of the Related Art Various manufacturing methods have been proposed for color filters for liquid crystal display elements. In particular, several methods are known for producing a color filter by forming a colored layer on the inner wall side of a cell of a substrate.

For example, there is a method of forming a colored layer by pattern printing of a colored ink by an offset printing method or the like. However, there is a limit to fineness of a printed pattern, and there is a problem such as a decrease in production yield.

[0004] A pigment dispersion method is often used as a method of applying a colored ultraviolet curable ink on the entire surface of a substrate and forming a color filter pattern by a photolithographic method. However, in the pigment dispersion method, it is necessary to perform coating, ultraviolet irradiation, and development steps three times in order to produce three primary color filters of red, green, and blue, and the manufacturing process is extremely complicated.

[0005] In addition, in a method of manufacturing a color filter using an electrodeposition coating method, a transparent electrode having a pattern is formed in advance on a portion to be electrodeposited, and three color filters are manufactured. To this end, the respective electrodes are sequentially energized to form a color filter film on the transparent electrodes. This method requires three electrodeposition operations, an operation to prevent color mixing due to overlapping colors, and a transparent electrode corresponding to the three colors. May be subject to restrictions.

As a rational method of manufacturing a color filter which solves these problems, a colored layer is formed by spraying a colored ink by an ink jet method (Japanese Patent Laid-Open No. 59-7 / 1984).
5205) has been proposed. In the case of performing coloring by the ink jet method, the droplet diameter is several tens μm, while the pixels of the color filter are approximately several tens μm on the short side and several hundred μm on the long side. For this reason, a uniform pixel can be obtained by providing a section defining pixels in advance on the glass substrate and spraying ink into the section by ink jetting to spread the ink in the section.

The above-mentioned proposal describes a method in which, when ink having good wettability to a glass substrate is used, a convex portion serving as a boundary is printed in advance with a substance having poor wettability to ink. . In addition, when using ink having poor wettability with respect to a glass substrate, there has been proposed a method of forming a pattern on glass in advance with a material having good wettability with the ink to help fix the ink.

[0008]

However, even if the protrusions are simply made ink-repellent and the recesses are made ink-philic, good results cannot be obtained if the control of the ink repellency is insufficient.
Although there is also an idea focusing on the critical surface tension of the black mask and the glass surface and the surface tension of the ink (Japanese Patent Laid-Open No. 6-347637), since the ink is ejected onto the substrate at a high speed in the ink jet method, such static A simple specification of the contact angle is not sufficient.

[0009] Further focusing on the dynamic contact angle,
A method of providing an ink repellent resin layer having a receding contact angle of 20 ° or more with ink (Japanese Patent Laid-Open No. 7-84122) is disclosed. However, when a black mask made of black resin is used, the receding contact angle is 20 ° without any special treatment.
Usually, a degree is obtained, and it is not possible to prevent the outflow of ink to adjacent pixels.

According to the study of the present inventors, the receding contact angle is not important but the advancing contact angle is important for preventing the ink from flowing out to the adjacent pixels. Further, it has been found that if the receding contact angle is too large, the cross-sectional shape of the formed pixel becomes strongly convex, and color unevenness or defective pixel occurs in the pixel, which is not preferable.

[0011]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and comprises forming a convex portion on a base material, and applying ink to a concave portion separated by the convex portion by an ink jet method. In a method of manufacturing a color filter, wherein a colored layer is formed by spraying ink on a concave portion to form a colored layer, the convex portion is subjected to an ink-repellent treatment, and an upper portion of the convex portion immediately before ink spraying is formed at an advancing contact angle of the sprayed ink. 90 ° or more, and the receding contact angle is 4 times larger than the advancing contact angle.
A method for producing a color filter, characterized in that the color filter is formed so as to be smaller than 0 ° and ink is sprayed on a concave portion separated by a convex portion to form a color filter.

Further, a method for producing a color filter in which the treating agent used for the ink repellent treatment mainly comprises a monomer having a structure represented by the following formula (1) or (2), or an oligomer or polymer thereof: provide.

[0013]

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R represents-(CH ₂ ) _m -R ^f , wherein R ^f is an alkyl group in which all hydrogen atoms are replaced by fluorine atoms, or carbon atoms of the alkyl group at one or more positions. X represents an alkyl group having an oxygen atom bonded between the bonds, m represents an integer of 0 to 10, R ¹ represents a hydrogen atom or a methyl group, and X ¹ , X ² , and X ³ each independently represent Means an alkyl group, an alkoxy group, a hydroxyl group, a halogen atom or an isocyanate group. Formula (2) is a basic unit structure of polymerization, and means a structure in which k units are connected by polymerization.

Further, the present invention provides a method for manufacturing a color filter in which after forming these convex portions, the concave portions are made ink-philic by etching, and then ink is sprayed by an ink jet method.

Further, the present invention provides a liquid crystal display device using a color filter formed by the method.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the method of manufacturing a color filter according to the present invention, first, a convex portion, preferably a convex portion formed by a black mask, is formed on a substrate in advance. After that, a coloring layer is formed by spraying a coloring ink by an inkjet method to form a color filter.

FIG. 1 is a sectional view schematically showing a color filter of the present invention. In FIG. 1, 1 is a substrate, 2 is a convex portion, 3 is a concave portion divided by the convex portion and the convex portion, 4 is an upper surface of the convex portion, 5 is a side surface of the convex portion, and 6 is formed by spraying and depositing on the concave portion. 2 shows a colored layer obtained. Only the concave portion 3 at the right end is shown in a state where no colored layer is formed for easy understanding of the description.

In this figure, only four convex portions and three concave portions are shown for the sake of simplicity, but the required number is provided. For example, in the case of a striped color filter, if 640 pixels are required, RG per pixel
Since three color filters of B are required, the protrusion is 192.
One and 1920 recesses are required. In a liquid crystal display device, a color filter pattern may be formed up to the periphery of a display pixel where no display is performed due to the precision of the gap between the substrates.

In the case of a stripe-shaped pattern, it is not necessary to form a convex portion in the longitudinal direction, but the pixel may be completely surrounded by the convex portion. In particular, in the case of a mosaic color filter, the periphery of a pixel is surrounded by a convex portion.

In the present invention, a glass substrate is generally used from the viewpoint of heat resistance. Although a transparent substrate is usually used as the substrate, the present invention can be applied to a reflective substrate or a substrate colored white. As the substrate, a substrate which has been subjected to surface treatment for preventing alkali elution, imparting gas barrier properties, or for other purposes may be used as necessary.

In the present invention, the convex portions for separating the colored layers are formed in a linear or lattice shape on the substrate. The shape of this projection is
Thus, the depressed concave portions may correspond to the pixels. For example, when a stripe-shaped color filter is formed, it is formed in a linear shape, and in order to correspond to a square pixel, it is formed in a lattice shape. Since this is appropriately determined by the shape of the pixel, various shapes such as a radial shape and a circumferential shape are also conceivable.

It is advantageous that the convex portion also serves as a black mask in a liquid crystal display device or the like. For this reason, in the following description, a description will be given based on an example in which the convex portion is also used as a black mask.
Then, a black material or a metal light-shielding layer may not be used.

As a method of forming the convex portion by using a black mask, for example, a metal chromium film, a laminate of chromium metal and chromium oxide, or a black layer made of a black pigment such as carbon black and a resin is formed. There is a method in which a photoresist is applied, the resist in the pixel portion is removed by a photolithography method, and a layer of metal chromium or the like is removed by etching. As a more cost-effective method, there is a method in which a photoresist in which a black pigment is dispersed is applied to form a black film, and this is patterned into a desired pattern by a photolithography method.

In the present invention, various well-known methods of forming a black mask capable of forming convex portions having a certain height in a desired pattern can be used. The projection may be formed by laminating a thin black mask and a thick resin layer.

The projections in the present invention play a role in preventing the sprayed ink from flowing into other pixels or bleeding when colored by the ink jet method. Therefore, it is preferable that the height of the convex portion is high to some extent, but it is also required that the overall flatness of the color filter is high, so that a height close to the thickness of the coloring layer is selected.

More specifically, the thickness is usually about 0.1 to 2 μm, although it depends on the amount of ink to be sprayed necessary for obtaining the desired coloring. If ink remains on the upper surface of the convex portion, flatness and uniformity of coloring between pixels are impaired. Therefore, the convex portion should be made ink-repellent, and the concave portion should be made ink-philic to improve ink spreading. preferable.
That is, the protrusion repels ink, and the substrate in the recess enhances ink affinity.

As for the ink repellency of the convex portions, it is necessary to set the advancing contact angle of the used ink to 90 ° or more from the viewpoint of preventing the outflow of the ink to the adjacent pixels. If it is smaller than this, it may cause color mixing or ink may remain on the upper part of the projection, which is not preferable. In particular, when the angle is 100 ° or more, good performance is obtained, which is preferable.

On the other hand, the sectional shape of each pixel is maintained flat,
From the viewpoint of obtaining a pixel having a small color unevenness and no defect, it is preferable that the receding contact angle is somewhat lower, and it is necessary that the receding contact angle of the ink is smaller than the advancing contact angle by 40 ° or more. If it is larger than this, the cross-sectional shape of the pixel is likely to be convex, and a density distribution will be formed in the pixel, and coloring failure will easily occur in a part of the pixel. In particular, when the receding contact angle is smaller than the advancing contact angle by 50 ° or more, the effect is high and preferable.

As a method of imparting ink repellency to the convex portions, a method of forming a material for forming the convex portions over the entire surface of the substrate, laminating an ink repellent treatment agent, and patterning the convex portions at the same time, or A method of forming a convex portion by an existing method, treating the entire surface of the substrate with an ink repellent agent, and then removing the ink repellency of the pixel portion by etching or the like is used.

Examples of the former include (1) a step of forming a black layer containing a photocurable resin and a black pigment on a substrate,
(2) a step of surface-treating the upper surface of the black layer with an ink repellent, and (3) a step of forming a desired black mask pattern by a photolithography step. Since the ink-repellent agent does not come into contact with the pixel portion that should be ink-philic, the possibility of contamination is small, and the process is simple and the cost is excellent.

On the other hand, examples of the latter include (1) a step of patterning a black mask on a substrate in advance by an existing method, (2) a step of applying an ink repellent treatment agent to the entire surface of the substrate, (3) etching and energy A step such as a step of removing the ink-repellent treatment agent from the pixel portion by a method such as line irradiation can be exemplified. In such a step, there is an advantage that there is little restriction on a solvent when the ink-repellent treatment agent is applied. The present invention is effective in any of the above cases, but especially in the latter, the ink repellent treatment is also easily performed on the side surface of the convex portion.
The effect of the present invention is remarkable because the effect of the ink-repellent treatment is great.

As the ink repellent for realizing the advancing contact angle and the receding contact angle of the present invention, various agents can be used according to the ink used. More specifically, formulas (1) to (1)
The compound represented by the formula (9) is preferable because a desired advancing contact angle and a receding contact angle are easily obtained.

[0034]

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[0035]

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R represents-(CH ₂ ) _m -R ^f , wherein R ^f is an alkyl group in which all hydrogen atoms are substituted by fluorine atoms, or carbon atoms of the alkyl group at one or more positions. An alkyl group in which an oxygen atom is bonded between the bonds, and m is an integer of 0 to 10.

R ¹ represents a hydrogen atom or a methyl group;
² and R ³ each independently represent a hydrogen atom or an alkyl group, and R ⁴ represents an alkylene group. X ¹ , X ² , X
³ is each independently an alkyl group, an alkoxy group, a hydroxyl group,
Y represents a halogen atom or an isocyanate group, and Y represents a hydroxyl group, a halogen atom or an isocyanate group.

The compounds represented by the formulas (2) and (8)
What is enclosed in parentheses is a basic unit structure of polymerization, and means a structure in which k units are connected by polymerization.

Of these, the use of the compounds represented by the formulas (1) and (2) is preferred because a desired advancing contact angle and receding contact angle are easily obtained. Among them, it is more preferable that R is a group of the following (a) or (b), since a desired contact angle is easily obtained.

(A):-(CH ₂ ) _m -C _n F _{2n + 1} n = _{1 to} 8, 10 ≧ m ≧ n−4, and when n ≦ 4, 10 ≧ m ≧ 0. _{(B) :-( CH 2) m} - (O-C 2 F 3 (CF 3))
_{n -O-C 3 F 7 n} = 1~20, m = 0~10.

Most other fluorine-based materials such as polytetrafluoroethylene having a fluorine atom in the main chain, such as polytetrafluoroethylene, satisfy the condition that the advancing contact angle is 90 ° or more. Is usually small, and it is difficult to satisfy the condition of the receding contact angle of the present invention. A fluorine-free silicone material or the like has a high contact angle with water, but it is difficult to satisfy an advancing contact angle of 90 ° or more with a commonly used ink containing a pigment or an organic solvent.

In addition, various resin binders such as acryl, styrene, and epoxy resins containing no fluorine may be mixed, and polymers and oligomers obtained by copolymerizing non-fluorine monomers may be used. It is necessary to keep the angle within a range where the angle takes an appropriate value.

When an ink repellent treatment is performed with these compounds, a method of diluting with a solvent, applying by a method such as spin coating, spray coating, roll coating, die coating, dip coating, and drying is employed.

As the solvent, various solvents for dissolving these ink repellents are used. In particular, when the ink repelling treatment is performed in a state where the resin forming the convex portion is not cured, that is, before the patterning of the convex portion, In the case where an ink-repellent process is performed and patterning is performed by a photolithography process after the process, it is necessary to prevent a resin forming a convex portion from being adversely affected.
For this reason, it is preferable to use a solvent of a perfluorinated compound such as perfluorooctane, perfluoro (2-butyltetrahydrofuran), perfluorotributylamine or the like which does not adversely affect the resin forming the projections.

In many cases, the concave portion is weakly ink-repellent due to the material forming the convex portion, the ink repellent agent, and other contamination generated during the process.

As a guide, the static contact angle of water is 20
° or less, and more preferably 10 ° or less. As a method for making ink-philic, a method of lightly etching the pixel portion with a strong alkali such as sodium hydroxide or hydrofluoric acid to expose a clean surface of the glass, or irradiating energy rays such as ultraviolet rays on the glass surface A method of removing contamination can be adopted. In particular, when hydrofluoric acid is used, the effect is high and preferable.

In the method in which the convex portions are patterned in advance and the entire surface is subjected to the ink repellent treatment, the ink repellent treating agent in the pixel portion is removed by etching or the like. .

As the polymer material for forming the convex portion, an acrylic resin or a polyimide resin is preferable. Further, a black resin may be added to use this as a black mask, and various photosensitive polymers and curing agents may be added to make the resin photosensitive.

In the present invention, the ink jet method is used as a coloring method. As an inkjet method, a method of continuously ejecting charged ink and controlling by an electric field,
Various methods, such as a method of intermittently ejecting ink using a piezoelectric element and a method of intermittently ejecting ink by heating ink and utilizing its foaming, can be adopted.

In the above description, the example using the water-based ink has been described, but the ink used may be oily or water-based. The use of water-based water-based inks is more preferable in view of the surface tension. The coloring material contained in the ink can use both a dye and a pigment. From the viewpoint of durability, the use of a pigment is more preferable.

In consideration of the process after coloring, a component which is cured by heating or which is cured by energy rays such as ultraviolet rays can be added to the ink in the present invention. Various thermosetting resins are widely used as components that are cured by heating. In addition, examples of the component that is cured by energy rays include those obtained by adding a photoreaction initiator to an acrylate derivative or a methacrylate derivative.

In particular, an acryloyl group in consideration of heat resistance,
Those having a plurality of methacryloyl groups in the molecule are more preferable. As these acrylate derivatives and methacrylate derivatives, water-soluble ones can be preferably used, and even those which are hardly soluble in water can be used after emulsification.

In the present invention, as described above, at least the upper surface of the convex portion is subjected to the ink-repellent treatment, so that defects caused by the flow of the ink to the adjacent pixels as shown in FIG. 2 can be reduced. FIG. 2 is a sectional view of a portion surrounded by two convex portions 12 on a substrate 11.
17 shows a state 17 in which the ink 16 sprayed on the two concave portions flows out to the adjacent pixel due to insufficient ink repellency of the convex portions.

In the present invention, by further controlling the receding contact angle of the convex portion, a color display with less unevenness of the colored layer and a good contrast can be obtained.

In the present invention, three color filters are usually formed by spraying inks of three colors RGB by an ink jet method. This color filter includes a liquid crystal display element, an electrophoretic display element, an electrochromic display element,
Used as a display element in combination with ZT or the like. It can also be used for applications that use color cameras and other color filters.

FIG. 3 is a schematic cross-sectional view showing an example in the case where the liquid crystal display device is used. In FIG. 3, 21 is a substrate, 22 is a convex portion, 23 is a colored layer, 24 is a flattening layer made of resin or the like covering the surface, 25 is In ₂ O ₃ —SnO _2.
(ITO), electrodes of SnO ₂ or the like, 26 is an alignment film of polyimide, polyamide, SiO or the like, 27 is the other substrate, 28
Is the other electrode, 29 is an alignment film, and 30 is a liquid crystal layer sandwiched between the electrodes.

In the present invention, a polarizing film, a reflection plate, a retardation plate, a light source, and the like can be disposed outside the liquid crystal cell, if necessary, to be used as a liquid crystal display device.

[0058]

【Example】

"Example 1 (Example)" A black-colored photoresist ("V-259BK" manufactured by Nippon Steel Chemical Co., Ltd.) was applied to a glass substrate by a spin coating method so as to have a target film thickness of 1.5 μm. For 10 minutes.

The ink repellent treating agent represented by the following formula (10) is perfluoro (2-butyltetrahydrofuran)
The solution was diluted to 0.1% by weight and applied on a photoresist film by spin coating. (CH ₃ O) ₃ —Si— (CH ₂ ) ₂ —C ₆ F ₁₃ (10) This substrate is exposed to 100 mJ through a photomask, immersed in a designated developing solution for 30 seconds, washed with pure water, 1 in ° C
Time post-cure was performed to obtain a substrate having a height of about 1.5 μm and a width of about 25 μm, also serving as a black mask.

The substrate was etched for 60 seconds with a processing solution obtained by diluting buffered hydrofluoric acid (a mixture of a 50% aqueous solution of HF and a 40% aqueous solution of NH ₄ F at a ratio of 1: 6) to 1%. Washed and air dried.

A water-based pigment ink (surface tension of about 40 dy) was applied to the concave portion surrounded by the convex portion of the substrate by an ink jet method.
n / cm) to form a striped R
A GB color filter was obtained. Table 1 shows the evaluation results of the color filters.

"Example 2 (Example)" A color filter was obtained in exactly the same manner except that the ink repellent treating agent of Example 1 was changed to the treating agent represented by the following formula (11). (NCO) ₃ —Si— (CH ₂ ) ₂ —C ₆ F ₁₃ (11) The concave portion surrounded by the convex portion of this substrate is sprayed with a water-based pigment ink by an inkjet method to form a stripe. An RGB color filter was obtained. Table 1 shows the evaluation results of the color filters.

"Example 3 (Example)" A color filter was obtained in exactly the same manner except that the ink repellent treating agent of Example 1 was changed to the treating agent represented by the formula (12). The concave portion surrounded by the convex portion of the substrate was sprayed with a water-based pigment ink by an ink jet method to obtain a striped RGB color filter. Table 1 shows the evaluation results of the color filters.

[0064]

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Example 4 (Example) A color filter was obtained in exactly the same manner as in Example 1 except that the ink-repellent treating agent was replaced by the treating agent represented by the formula (13). The concave portion surrounded by the convex portion of the substrate was sprayed with a water-based pigment ink by an ink jet method to obtain a striped RGB color filter. Table 1 shows the evaluation results of the color filters.

[0066]

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"Example 5 (Example)" A black colored photoresist ("416" manufactured by Tokyo Ohka Co., Ltd.) was applied to a glass substrate.
S ") was applied by spin coating so as to have a target film thickness of 1.5 μm, and heat-treated at 110 ° C. for 10 minutes. The substrate is exposed to 100 mJ through a photomask, immersed in a designated developing solution for 30 seconds, washed with cold water, and post-cured at 230 ° C. for 1 hour, and serves as a black mask, having a height of about 1.5 μm and a width of 1.5 μm. Obtained a substrate having a projection of about 25 μm.

The ink-repellent treating agent represented by the formula (Formula 14) is dissolved in a fluorine-based solvent ("Asahiclean AK-225" manufactured by Asahi Glass Co., Ltd.) on the entire surface of the substrate, and is applied by dip coating. Heat-treated at 1 ° C. for 1 hour. This was washed with the above-mentioned fluorine-based solvent, etched with buffered hydrofluoric acid as in Example 1, washed with water and air-dried.

[0069]

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The concave portion surrounded by the convex portion of the substrate was sprayed with an aqueous pigment ink by an ink jet method to obtain a striped RGB color filter. Table 1 shows the evaluation results of the color filters.

Example 6 (Comparative Example) A black colored photoresist ("416" manufactured by Tokyo Ohka Co., Ltd.) was applied to a glass substrate.
S ") was applied by spin coating so as to have a target film thickness of 1.5 μm, and heat-treated at 110 ° C. for 10 minutes. The substrate was exposed to 100 mJ through a photomask, immersed in a designated developer for 30 seconds, washed with cold water, and post-cured at 230 ° C. for 1 hour.

Further, after etching with buffered hydrofluoric acid in the same manner as in Example 1, washing with water and air-drying were carried out to perform an ink-repellent treatment having a convex portion having a height of about 1.5 μm and a width of about 25 μm, also serving as a black mask. A substrate not to be obtained was obtained. Spraying is performed on the concave portion surrounded by the convex portion of the substrate by using an aqueous pigment ink by an ink-jet method, thereby forming a striped RG.
B color filter was obtained. Table 1 shows the evaluation results of the color filters.

Example 7 (Comparative Example) A color filter was obtained in exactly the same manner as in Example 5, except that the ink repellent treating agent was changed to the compound represented by the formula (15). The concave portion surrounded by the convex portion of the substrate was sprayed with a water-based pigment ink by an ink jet method to obtain a striped RGB color filter. Table 1 shows the evaluation results of the color filters.
Shown in

[0074]

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In Table 1 below, the advancing contact angle is the advancing contact angle (°) of the ink in the convex portion, the receding contact angle is the receding contact angle (°) of the ink in the convex portion, and the static contact angle is the static water angle in the concave portion. Mean contact angle (°).

The advancing contact angle, receding contact angle and static contact angle were measured using a CA-X type contact angle meter manufactured by Kyowa Interface Science Co., Ltd. The advancing contact angle and receding contact angle were measured by a diffusion / shrinkage method. The typical contact angle was measured by a droplet method. The receding contact angle was measured in a state where the liquid droplet and the liquid suction nozzle were separated.

The outflow of the ink means the presence or absence of the outflow of the ink into the adjacent concave portion, the color omission means the presence or absence of the color omission at the peripheral portion of the pixel, and the color unevenness means the presence or absence of the color unevenness in the pixel. "O" indicates a product without any defect (good product), and "x" indicates a product with a defect (defective product). “△” indicates that some pixels have a defect.

In this evaluation, assuming that color omission cannot be clearly identified, 5 or less pixels per 1000 pixels having color omission of 50 μm ² or more are evaluated as “O” and “6 to 50 pixels”. ”Was evaluated as“ Δ ”, and when the value exceeded that, and even one pixel in which color omission was clearly identified with the naked eye, was evaluated as“ X ”.

Regarding the color unevenness, the center of the pixel and
If the color difference (ΔE ^* _uv ) from the position 20 μm from the edge of the pixel is 2.0 or less, the _mark is “○”. If the color difference exceeds 2.0 and 5.0, the mark is “△”. × ”.

As a result, in Examples 1, 2, 3, 4, and 5,
There were no defects such as outflow of ink into the adjacent concave portion, color loss around the pixel, and color unevenness in the pixel. On the other hand, Example 6
In this method, the ink easily flowed out to the adjacent pixels after passing over the black mask, and it was impossible to form a pattern. In Example 7, no outflow to adjacent pixels occurred, but color loss and unevenness occurred around the pixels.

Example 8 (Example), Example 9 (Comparative Example) Example 8
In the same manner as in Example 1 except that the pixels of Example 1 are formed in a dot shape and a convex portion is provided so that RGB pixels are arranged in a mosaic arrangement, a water-based pigment ink is applied to a concave portion surrounded by the convex portion by an inkjet method. And spraying was performed to obtain RGB color filters in a mosaic arrangement. Similarly, as Example 9,
A mosaic-arranged color filter was obtained in the same manner as in Example 6.

As in the color filter of Example 1, the color filter of Example 8 did not cause defects such as outflow of ink to the adjacent concave portion, color omission at the periphery of the pixel, and color unevenness within the pixel. In Example 9, as in Example 6, it was difficult to color in a pattern.

"Example 10 (Example)" A flattening layer of resin is formed on the color filter of Example 1, ITO is formed, patterning is performed, an alignment film of resin is formed, and rubbing is performed. One substrate was formed. Next, ITO was formed on a glass substrate, which was patterned, a resin alignment film was formed, and rubbing was performed to form a second substrate. The first substrate and the second substrate were arranged so that the electrode surfaces face each other, and the periphery was sealed to form an empty cell.

A nematic liquid crystal is injected into the empty cell,
The inlet was sealed to form a liquid crystal cell. A phase difference plate and a polarizing plate were arranged on both sides of the liquid crystal cell to manufacture an FSTN type liquid crystal display device. This liquid crystal display device was capable of beautiful color display.

[0085]

[Table 1]

[0086]

According to the present invention, when a color filter is manufactured by spraying ink by an ink-jet method having good productivity, the ink does not easily adhere onto the convex portions, and the cross-sectional shape of the pixel is good. Has the effect of preventing color unevenness and missing pixels. This can improve display performance as a liquid crystal display element. The present invention can be applied to various applications within a range that does not impair the effects of the present invention.

[Brief description of the drawings]

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

FIG. 2 is a schematic cross-sectional view showing a state when ink is sprayed in a conventional example.

FIG. 3 is a schematic cross-sectional view of a liquid crystal display device using the color filter of the present invention.

[Explanation of symbols]

 1: substrate 2: convex portion 3: concave portion 4: upper surface of convex portion 5: side surface of convex portion 6: colored layer

Claims (4)

[Claims] 1. A method of manufacturing a color filter, wherein a convex portion is formed on a base material, and ink is sprayed to a concave portion separated by the convex portion by an ink jet method to deposit the ink in the concave portion to form a colored layer. And performing an ink-repellent treatment on the convex portion so that the upper portion of the convex portion immediately before ink spraying has an advancing contact angle of the sprayed ink of 90 ° or more and a receding contact angle of 40 ° or more smaller than the advancing contact angle. And forming a color filter by spraying ink on a concave section defined by the convex section. 2. The color filter according to claim 1, wherein the treating agent used for the ink repellent treatment mainly comprises a monomer having a structure represented by the following formula (1) or (2), or an oligomer or polymer thereof. Manufacturing method. Embedded image However, R means-(CH ₂ ) _m -R ^f , wherein R ^f is an alkyl group in which all hydrogen atoms have been replaced by fluorine atoms, or at one or more positions between carbon-carbon bonds of the alkyl group. An alkyl group to which an oxygen atom is bonded, m
Represents an integer of 0 to 10, R ¹ represents a hydrogen atom or a methyl group, and X ¹ , X ² and X ³ each independently represent an alkyl group, an alkoxy group, a hydroxyl group, a halogen atom or an isocyanate group. means. Formula (2) is a basic unit structure of polymerization, and means a structure in which k units are connected by polymerization. 3. The method for producing a color filter according to claim 1, wherein after forming the convex portion, the concave portion is made ink-philic by etching, and then ink is sprayed by an ink jet method. 4. A liquid crystal display device using a color filter formed by the method according to claim 1.