JPH10104607A - Color filter and its production and liquid crystal element formed by using the color filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify stags, to enhance the adhesion property between a substrate consisting of an inorg. material and color filters and to prevent the peeling of the color filters by discharging coloring ink 7 by an ink jet system to an ink acceptive layer having a specific compsn., thereby coloring the layer. SOLUTION: The color filters are formed by coloring the ink acceptive layer contg. an acrylic copolymer contg. at least either of the repeating units expressed by formula I and formula II and a silicon compd. contg. a glycidyl group and alkoxy group. In the formulas, R1 , R3 are hydrogen atoms or methyl groups; R2 , R4 , R5 are hydrogen atoms or 1 to 5C alkyl groups. Since the ink acceptive layer contains the specific acrylic copolymer and the specific silicon compd. in such a manner, the glycidyl group and the acrylic copolymer and the alkoxy group and the substrate couple with each other respectively, by which the secure adhesion property between the color filters and the substrate is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter used in a color display device and the like and a method of manufacturing the same, and more particularly, to a color liquid crystal display device used in a color television, an in-vehicle television, a personal computer, a pachinko game board, and the like. The present invention relates to a suitable color filter and a manufacturing method thereof, and a liquid crystal element using the color filter.

[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, tends to increase. However, for further widespread use, it is necessary to reduce the cost of the liquid crystal display. In particular, there is an increasing demand for reducing the cost of a color filter having a high specific gravity. Conventionally, various methods have been tried to satisfy the above requirements while satisfying the required characteristics of the color filter, but no method has yet been established that satisfies all the required characteristics. The respective methods will be described below.

[0003] The first method most frequently used is a dyeing method. In the dyeing method, a water-soluble polymer material, which is a material for dyeing, is applied on a glass substrate, and is patterned into a desired shape by a photolithography process. Get a pattern. By repeating this three times, R (red), G
(Green) and B (blue) coloring layers are formed.

[0004] 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 formed on a substrate, and a monochromatic pattern is obtained by patterning the photosensitive resin layer. This process is further repeated three times to form R, G, B colored layers.

As a third method, there is an electrodeposition method. In this method, a transparent electrode is patterned on a substrate, and immersed in an electrodeposition coating solution containing a pigment, a resin, an electrolytic solution, and the like to electrodeposit a first color. This process is repeated three times to form R, G, and B colored layers, and finally firing.

As a fourth method, a pigment is dispersed in a thermosetting resin, and printing is repeated three times so that R, G,
After separately applying B, the resin is thermally cured to form a colored layer. In any method, a protective film is generally formed on the colored layer.

The common feature of these methods is that R,
It is necessary to repeat the same process three times in order to color the three colors G and B, which increases the cost. In addition, there is a problem that the yield decreases as the number of steps increases. Further, in the electrodeposition method, since the pattern shape that can be formed is limited, it is difficult to apply the current technology for TFT. Further, the printing method is not suitable for forming a fine pitch pattern due to poor resolution and smoothness.

[0008]

SUMMARY OF THE INVENTION In order to make up for these drawbacks, Japanese Patent Application Laid-Open Nos. 59-75205 and 63-23
Japanese Patent Application Laid-Open No. 5901 or Japanese Patent Application Laid-Open No. Hei 1-217320 describes a method for producing a color filter using an ink jet method, but a satisfactory one has not yet been obtained.

In many cases, the substrate on which the color filter is formed is made of an inorganic material, and the color filter itself is made of an organic material. Therefore, it is inevitable that the adhesion between the substrate and the color filter becomes weak. In particular, when a liquid crystal element is used in a high-temperature, high-humidity environment, there is a problem that a color filter used as a component of the liquid crystal element is peeled off from a substrate or deteriorated.

[0010] An object of the present invention is to solve the above-mentioned problems and to carry out a manufacturing process using an ink-jet method without deteriorating necessary properties such as heat resistance, solvent resistance and resolution of a conventional color filter. Another object of the present invention is to provide a color filter which can be simplified and reduced in cost, and which can withstand use in a high-temperature and high-humidity environment even when formed on a substrate made of an inorganic material.

[0011]

SUMMARY OF THE INVENTION According to the present invention, a substrate made of an inorganic material is simplified by discharging a colored ink onto an ink receiving layer having a specific composition formed in advance by an ink jet method and coloring the ink. And the color filter can be improved in adhesion to prevent the color filter from peeling off.

That is, the invention of claims 1 to 4 at least
An acrylic copolymer containing at least one of the repeating units represented by the following formulas (I) and (II):

[0013]

Embedded image (However, R ₁ and R ₃ are a hydrogen atom or a methyl group, R ₂ and R 3
_4, R ₅ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. A color filter characterized by coloring an ink receiving layer containing a silicon compound containing a glycidyl group and an alkoxy group.
An acrylic copolymer containing at least one of the repeating units represented by the following formulas (I) and (II):

[0014]

Embedded image (However, R ₁ and R ₃ are a hydrogen atom or a methyl group, R ₂ and R 3
_4, R ₅ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. A) a step of forming an ink receiving layer containing a silicon compound containing a glycidyl group and an alkoxy group on a surface on which a color filter is formed, and a step of discharging ink to the ink receiving layer by an ink jet method and coloring the ink receiving layer. A method for producing a color filter, characterized by the following:
The present invention is a liquid crystal device using the color filter of the present invention.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic sectional view of a display section of an embodiment of a liquid crystal device using a color filter of the present invention. In the figure, 1a and 1b are transparent substrates, 2a and 2b are electrodes, 3a and 3b are alignment films, 4 is a black matrix, 5
Is a color filter, and coloring portions 5a to 5b (R, G,
B) and the non-colored portion 6. 7 is a protective film, 8 is a liquid crystal,
9a and 9b are polarizing plates.

FIG. 2 is a schematic cross-sectional view showing a process of manufacturing the color filter of the liquid crystal element. Hereinafter, the color filter of the present invention and a method of manufacturing the same will be described with reference to FIG.
Steps -a to e correspond to (a) to (e) in FIG.

Step-a Chromium or the like is formed on the substrate 1b by sputtering or the like, and is patterned into a predetermined shape to form a black matrix 4. As the substrates 1b and 1a, glass is generally used, but plastics or the like may be used as long as they have required characteristics such as transparency and strength as a color filter according to applications. The thickness of the black matrix 4 is usually 0.1 to 0.5 μm in the case of a liquid crystal element.

Step-b: An ink receiving layer 21 is formed on the entire surface of the substrate 1b on which the black matrix 4 is formed. In the present invention, the ink receiving layer 21 is a material capable of absorbing ink ejected by an ink jet method described later and forming the protective film 6, the electrode 2b, and the alignment film 3b thereon. And an acrylic copolymer containing at least one of the repeating units represented by the formula (II) and a compound containing a glycidyl group, an alkoxy group and silicon.

[0019]

Embedded image (However, R ₁ and R ₃ are a hydrogen atom or a methyl group, R ₂ and R 3
_4, R ₅ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. )

Examples of the monomer containing a repeating unit represented by the above formula (I) include N-methylacrylamide, N-methoxymethylacrylamide, N-ethoxymethylacrylamide, N-isopropoxymethylacrylamide, N-methylolmethacrylamide. , N-methoxymethyl methacrylamide, N-ethoxymethyl methacrylamide, and the like, but are not limited thereto.

The monomers containing the repeating unit represented by the above formula (II) include N, N-dimethylolacrylamide, N, N-dimethoxymethylacrylamide, N, N-diethoxymethylacrylamide, N
-Dimethylol methacrylamide, N, N-dimethoxymethyl methacrylamide, N, N-diethoxymethyl methacrylamide, and the like, but are not limited thereto.

The above monomers are copolymerized alone or with other vinyl monomers. Other vinyl monomers include acrylic acid, methacrylic acid, acrylates such as methyl acrylate and ethyl acrylate, methacrylates such as methyl methacrylate and ethyl methacrylate, hydroxymethyl methacrylate, and hydroxy. Ethyl methacrylate, hydroxymethyl acrylate, hydroxyl-containing vinyl monomers such as hydroxyethyl acrylate, and other styrene, α-methylstyrene, acrylamide, methacrylamide, acrylonitrile, allylamine, vinylamine, vinyl acetate, vinyl propionate, and the like. But they are of course not limited to these.

On the other hand, as the silicon compound containing a glycidyl group and an alkoxy group, γ-glycidoxypropyltrimethoxysilane is preferably used.

In the present invention, the weight ratio of the acrylic copolymer to the silicon compound containing a glycidyl group and an alkoxy group is preferably from 100: 50 to 100: 0.1. The ink receiving layer 21 is usually formed by coating and prebaked. In the case of a liquid crystal element, the film thickness is usually formed to be about 0.3 to 3.0 μm.

Step-c The ink receiving layer 21 is exposed using a photomask 22 and post-baked to form a non-colored portion 6. The width of the non-colored portion 6 is formed to be about 1.0 to 30.0 μm.

Step-d R, G, and B ink droplets are ejected using the ink jet head 23, and the unexposed portions in Step-c are colored, and the colored portions 5a to 5c of each color are subjected to pre-baking and post-baking.
Is formed.

As the ink jet system used in the present invention, a bubble jet type using an electrothermal converter or a piezo jet type using a piezoelectric element can be used as an energy generating element. The pattern can be set arbitrarily.

In the present invention, the coloring ink is not limited to a liquid ink at room temperature, but may be an ink which solidifies at room temperature or below, and which is softened at room temperature or liquid, or the ink described above. In general, in the ink jet method, the temperature of the ink itself is controlled within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. A liquid material is preferably used.

In the present embodiment, the non-colored portion 6 is formed in the step-c. In the non-colored portion 6, the ink is repelled and not absorbed, so that color mixing between adjacent colored portions can be avoided. .

When an exposed part and an unexposed part are formed in the ink receiving layer as in this embodiment, a non-uniform stress is generated inside the ink receiving layer due to a rapid condensation reaction in the exposed part. Therefore, when the adhesion between the color filter and the substrate is weak, the uneven stress in the entire color filter further promotes the adhesion breakdown.

In the present invention, since the ink receiving layer contains a specific acrylic copolymer and a specific silicon compound, a glycidyl group and an acrylic copolymer, and an alkoxy group and a substrate are respectively bonded. Thereby, strong adhesion between the color filter and the substrate can be obtained, and even when uneven stress occurs in the color filter as in the present embodiment, peeling of the color filter from the substrate can be prevented. .

Step-d: A protective film 7 is formed on the color filter. As the protective film 7, a resin film of a photo-curing type, a thermo-setting type, or a combination of heat and light, an inorganic film formed by vapor deposition, sputtering, or the like can be used. Any material that can withstand the process or the like can be used.

The electrode 2b and the alignment film 3b are formed on the protective film 7 formed by the above steps.
The liquid crystal element shown in FIG. 1 is formed by opposing and adhering to the other substrate having the electrode 2a and the alignment film 3a formed thereon over a sealing material via a sealing material and filling the liquid crystal. The alignment film 3a,
Orientation treatment such as rubbing treatment is usually performed on the surface of 3b, whereby liquid crystal molecules can be aligned in a certain direction.

In the above embodiment, the electrode 2
a and 2b are each formed in a stripe shape and arranged so as to intersect with each other, whereby a pixel is formed by the intersecting portion, and each colored portion 5a to 5c of the color filter is arranged so as to correspond to the pixel. I have.

Further, polarizing plates 9a and 9b are adhered outside the substrates 1a and 1b, respectively.

As a backlight, a combination of a fluorescent lamp and a scattering plate (not shown) is generally used, and the liquid crystal element functions as an optical shutter for changing the transmittance of light 10 of the backlight. Is displayed.

The liquid crystal used in the present invention is not particularly limited, and may be a TN type liquid crystal or a ferroelectric liquid crystal (FLC).
Etc. are preferably used.

Further, the color filter of the present invention can be suitably used as a color filter other than a liquid crystal element.

[0039]

The present invention will be described below in detail with reference to examples.

Example 1 A 200 mm square chromium thin film was formed to a thickness of 0.2 μm on a glass substrate made of alkali-free glass whose surface was polished by sputtering, and had an opening 31 as shown in FIG. 3 by photolithography. By patterning into a shape, a black matrix 4 was formed. Incidentally, W = 60 μm, L = 120 μm, d ₁ = 20 μm
m and d ₂ = 100 μm.

Next, an acrylic copolymer having the following composition was prepared.

Acrylic acid 3 parts by weight Methyl methacrylate 49 parts by weight Hydroxyethyl methacrylate 29 parts by weight N-methylolacrylamide 19 parts by weight Subsequently, 97 parts by weight of the above acrylic copolymer was added to 3 parts by weight of triphenylsulfonium hexafluoroantimonate. Was mixed with 83 parts by weight of the mixture and 17 parts by weight of γ-glycidoxypropyltrimethoxysilane, and 85 parts by weight of ethyl cellosolve was added to 15 parts by weight of the mixture to prepare an ink receiving layer liquid.

The ink receiving layer liquid was applied onto the substrate on which the black matrix was formed by spin coating, and then dried at 90 ° C. for 10 minutes to form a photosensitive resin layer having a thickness of 2 μm, which was used as an ink receiving layer.

Next, 150 mJ / c through a photomask having an opening smaller than the width of the black matrix.
After pattern exposure with an exposure amount of m ² , a heat treatment was performed on a hot plate at 120 ° C. for 90 seconds.

R, G, and B color inks were prepared with the following compositions. (R) C.I. I. Acid Red 118 5 parts by weight Ethylene glycol 20 parts by weight Isopropyl alcohol 5 parts by weight Water 70 parts by weight

(G) C.I. I. Acid Green 25 5 parts by weight Ethylene glycol 20 parts by weight Isopropyl alcohol 5 parts by weight Water 70 parts by weight

(G) C.I. I. Acid Blue 113 5 parts by weight Ethylene glycol 20 parts by weight Isopropyl alcohol 5 parts by weight Water 70 parts by weight

Further, the above-mentioned ink is discharged to a predetermined unexposed portion using an ink-jet head to color the R, G, B matrix pattern, dried at 90 ° C. for 20 minutes, and subsequently at 230 ° C. for 60 minutes. Was performed to cure the colored resin layer.

Subsequently, a two-pack type thermosetting resin composition [79:21 mixture of Optmer SS6500 (manufactured by Nippon Synthetic Rubber Co.) and Optmer SS0500 (manufactured by Nippon Synthetic Rubber Co., Ltd.)] is spun to a thickness of 1 μm. Coat, 90 ℃
After drying for 20 minutes at, a heat treatment was performed at 230 ° C. for 60 minutes to cure and form a protective film.

Observation of the thus prepared color filter for a liquid crystal element by an optical microscope showed that there was no color mixture, uneven color, or color omission.

Next, the adhesion between the substrate and the color filter was evaluated by the following means. (1) A 1 mm cross cut is placed in the color filter. (2) A pressure cooker test (120 ° C., saturated vapor pressure; PCT) is performed on the color filter of (1). (3) A 1 mm cross cut is made in the color filter of (2). (4) A tape peeling test of the cross cut portion is performed at a peeling angle of 45 ° with the substrate. (5) Count the peeled cells.

As a result of the above evaluation test, no peeling was observed even after 60 hours of PCT.

Further, FIG.
When the liquid crystal element shown in (1) was manufactured and driven, high contrast and high-definition color display were possible.

Example 2 Example 1 was repeated except that 9 parts by weight of γ-glycidoxypropyltrimethoxysilane was mixed with 91 parts by weight of a mixture of an acrylic copolymer and triphenylsulfonium hexafluoroantimonate. In the same manner as in Example 1, a color filter was produced.

When the adhesion of the color filter of this example to the substrate was evaluated in the same manner as in Example 1, no peeling was observed even after 36 hours of PCT.

Comparative Example 1 A color filter was produced in the same manner as in Example 1 except that γ-glycidoxypropylmethoxysilane was not mixed.

When the adhesion of the color filter of this comparative example to the substrate was evaluated in the same manner as in Example 1, peeling of the color filter from the substrate occurred by a tape peeling test after 36 hours of PCT.

[0058]

As described above, according to the present invention,
Since a color filter is formed by simultaneously coloring a plurality of colors by the ink jet method, color unevenness and color omission are not caused, and the cost in the manufacturing process can be significantly reduced. By providing a non-colored portion between adjacent colored portions, color mixing is prevented, and an excellent color filter can be obtained. Furthermore, in the present invention, since the ink receiving layer is formed with a specific composition, a color filter having high adhesion to a substrate can be obtained.

Accordingly, by using the color filter of the present invention for a liquid crystal element, it is possible to withstand use in a high-temperature and high-humidity environment and to manufacture a high-contrast, high-definition liquid crystal element at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of one embodiment of a liquid crystal element of the present invention.

FIG. 2 is a cross-sectional view showing one embodiment of a process for manufacturing a color filter of the present invention.

FIG. 3 is a plan view showing a pattern shape of a black matrix formed in an example of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1a, 1b Substrate 2a, 2b Electrode 3a, 3b Alignment film 4 Black matrix 5a-5b Colored part 5 Color filter 6 Non-colored part 7 Protective film 8 Liquid crystal 9a, 9b Polarizer 10 Light of backlight 21 Ink receiving layer 22 Photo mask 23 inkjet head 31 opening

Claims (9)

[Claims] At least the following formulas (I) and (I)
An acrylic copolymer containing at least one of the repeating units represented by I), and (However, R ₁ and R ₃ are a hydrogen atom or a methyl group, R ₂ and R 3
_4, R ₅ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. A color filter obtained by coloring an ink receiving layer containing a silicon compound containing a glycidyl group and an alkoxy group. 2. The color filter according to claim 1, wherein the color filter comprises a colored portion and a non-colored portion located between adjacent colored portions.
The color filter described. 3. The color filter according to claim 1, wherein the silicon compound containing a glycidyl group and an alkoxy group is γ-glycidoxypropyltrimethoxysilane. 4. The weight ratio of the acrylic copolymer and the silicon compound containing a glycidyl group and an alkoxy group is as follows:
The color filter according to claim 1, wherein the ratio is 100: 50 to 100: 0.1. 5. At least the following formulas (I) and (I)
An acrylic copolymer containing at least one of the repeating units represented by I), and (However, R ₁ and R ₃ are a hydrogen atom or a methyl group, R ₂ and R 3
_4, R ₅ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. A) forming an ink receiving layer containing a silicon compound containing a glycidyl group and an alkoxy group on the surface on which the color filter is formed, and discharging the ink to the ink receiving layer by an ink jet method and coloring the ink receiving layer. A method for producing a color filter, comprising: 6. The method for producing a color filter according to claim 5, further comprising a step of pattern-exposing said ink-receiving layer and a step of discharging ink by ink-jetting to an unexposed portion to color. 7. The method for producing a color filter according to claim 5, wherein the silicon compound containing a glycidyl group and an alkoxy group is γ-glycidoxypropyltrimethoxysilane. 8. The weight ratio of the acrylic copolymer and the silicon compound containing a glycidyl group and an alkoxy group is as follows:
The color filter according to claim 5, wherein the ratio is 100: 50 to 100: 0.1. 9. A liquid crystal is sandwiched between a pair of substrates each having an electrode, and the color filter according to claim 1 is provided on one of the pair of substrates. Liquid crystal element.