JPH10239511A - Manufacture of color filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an ink filling recessed part for forming a color pattern layer in a simple processing step. SOLUTION: An original disc 12 having a plurality of predetermined array of projected parts 13 is manufactured (a first step). Then, the original disc 12 is brought into close contact with a substrate 10 through ink filling layer forming material 11 and an ink filling layer 14 is formed by solidifying the ink filling layer forming material 11 and then the ink filling layer 14 having a plurality of ink filling recessed parts 15 is transferred and formed on the substrate 10 by separating the substrate 10 and the ink filing layer 14 integrally from the original disc 12 (a second step). Then, a color pattern layer 16 is formed in respective ink filling recessed parts 15 by filling ink of a predetermined color.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a color filter used for a liquid crystal display panel or the like.

[0002]

2. Description of the Related Art As a method for producing a color filter such as a liquid crystal display panel, there are a dyeing method, a pigment dispersion method, a printing method, an electrodeposition method and the like.

[0003] The dyeing method is a method in which a photosensitive agent is added to a water-soluble polymer material, which is a dyeing material, to be sensitized, and the photosensitive material is patterned in a lithography process, and then immersed in a dye solution to obtain a colored pattern.

For example, first, a light-shielding portion (generally referred to as a black matrix in black) on a glass substrate.
BM). Then, a dyeing material is added to the water-soluble polymer material to make it difficult to dissolve in a solvent when exposed to light, and is applied to the substrate on which the BM is formed. Next, by exposing and developing only a part of the dyeing material through a mask, patterning is performed so that the dyeing material remains only in the first color region. Then, the first coloring layer is formed by immersing the dyeing material in a dyeing solution to dye and fix the dyeing material. By repeating this process three times, three color filters are formed.

[0005] The color filter produced by this dyeing method has a high transmittance and a vivid color, but is inferior in light resistance, heat resistance and moisture absorption.

Next, the pigment dispersion method is a method of repeating a process of applying a photosensitive resin in which a pigment is dispersed to a substrate and patterning the same to obtain a monochromatic pattern. Whereas the dyeing method was a method of dyeing after patterning the material for dyeing, the pigment dispersion method was
A pre-colored photosensitive resin is applied to the substrate.
And the color filter manufactured by the pigment dispersion method,
It has the property that the transmittance is somewhat low although the durability is high.

[0007] Furthermore, the photosensitive resin layer has a large problem in terms of material utilization efficiency, since at least 70% or more of the applied photosensitive resin layer is removed and discarded.

[0008] The printing method is a method in which a paint in which a pigment is dispersed in a thermosetting resin is repeatedly applied in three colors by printing, and the resin is thermoset to form a colored layer. This printing method has a simple process but has poor flatness.

In the electrodeposition method, a patterned transparent electrode is provided on a substrate, and this is immersed in an electrodeposition coating solution containing a pigment, a resin, an electrolytic solution, and the like to electrodeposit a first color. And
This is a method of repeating this step three times and finally firing.
This electrodeposition method is excellent in flatness and is effective if it is a color arrangement of a stripe pattern. However, it is difficult to form a color arrangement such as a mosaic pattern.

Among the above production methods, the printing method has a drawback in terms of accuracy, and the electrodeposition method has a drawback that the pattern is limited. Therefore, the dyeing method and the pigment dispersion method have been mainly used in the past. Was.

[0011] However, the dyeing method and the pigment dispersion method are the first.
A lithography process is required each time the pixel regions of the second, third, and second colors are formed, which has been a major obstacle to improving the mass productivity of color filters. As a method of forming a pixel without repeating the lithography process for each color as described above, JP-A-59-75205 and JP-A-6-75205
A number of methods for manufacturing a color filter by an ink jet method have been disclosed, such as Japanese Patent Application Laid-Open No. 1-245106. By forming a colored pattern by an inkjet method, it is intended to improve the use efficiency of the material, shorten the process, and further control the shape of the colored pattern to obtain a low-cost and high-quality color filter. .

In the method of manufacturing a color filter using these ink jet systems, in order to prevent the ink from spreading to areas other than the respective colored regions and to realize high-precision coloring, the color filters are formed on the substrate in advance by a photolithography method. A method utilizing a pixel partitioning portion has been devised. Forming a concave portion for ink filling on the substrate by the pixel partitioning portion,
The shape is controlled by filling the ink filling recesses with ink to form a colored pattern.

[0013] In many cases, the pixel partitioning portion has a BM function by being formed of a light-shielding material.

[0014]

However, according to the above-described color filter manufacturing method, since the pixel partitioning portions are formed one by one by a photolithography method, the ink-jet method such as improving the use efficiency of the material and shortening the process is required. It has the problem of reducing the advantages of the scheme.

Therefore, the present invention solves such a problem, and an object of the present invention is to provide a method of manufacturing a color filter which can form an ink filling recess for forming a colored pattern in a simple process. To provide. In particular, by combining with the inkjet method,
It is an object of the present invention to provide a method for manufacturing an inexpensive and high quality color filter with a reduced number of steps.

[0016]

A method of manufacturing a color filter according to the present invention comprises a first step of manufacturing a master having a plurality of convex portions arranged in a predetermined arrangement, and a step of mounting the master on a substrate via an ink-filled layer forming material. After the ink-filled layer forming material is solidified to form an ink-filled layer, the substrate and the ink-filled layer are integrally peeled off from the master to form a plurality of ink-filled recesses on the substrate. And a third step of forming a colored pattern layer by filling each of the ink filling recesses with ink of a preset color to form a colored pattern layer. I do.

In short, the present invention is a method for transferring and forming an ink-filled layer having an ink-filled concave portion on a substrate using a master as a mold. Once the master is manufactured, it can be used as many times as the durability permits, so that the master can be omitted in the manufacturing process of the second and subsequent color filters, and the number of processes and cost can be reduced.

As a method of manufacturing a master, there are, for example, the following methods.

(1) A step of forming a resist layer according to a predetermined pattern on a master disk base material, and then forming the projections on the master disk base material by etching to form a master disk.

According to this step, by changing the etching conditions, the shape and the surface roughness of the convex portion can be controlled with high precision and freely.

As the master substrate, a silicon wafer is preferable. The technique of etching a silicon wafer is used as a technique for manufacturing a semiconductor device, and enables high-precision processing.

(2) A resist layer corresponding to a predetermined pattern is formed on the second master, then the second master and the resist layer are made conductive, and a metal is electrodeposited by electroplating to form a metal. After forming a layer, the metal layer is peeled from the second master and the resist layer to form a master.

The metal master obtained by this step is generally excellent in durability and peelability. Next, the ink filling layer forming material is preferably a substance that can be cured by applying energy. By using such a substance, it is possible to easily fill the ink filling layer forming substance even into the fine portions of the concave portions on the master, and therefore, the ink filling concave portions in which the convex shapes on the master are precisely transferred. Can be formed. Preferably, the energy is light, heat, or both light and heat.
By doing so, a general-purpose exposure apparatus, a baking furnace, and a hot plate can be used, and it is possible to reduce equipment costs and save space.

As such a substance, for example, there is an ultraviolet curable resin. As the UV-curable resin, an acrylic resin is preferable because it has excellent transparency and various commercially available resins and photosensitive agents can be used.

Next, in the third step, the ink is preferably filled by an ink jet method. According to the inkjet method, the speed of filling the ink can be increased, and the ink is not wasted.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 2 shows a first embodiment of the present invention.
FIG. 7 is a view showing a step of manufacturing a master in the embodiment.

Specifically, the method is performed by the following method.

First, as shown in FIG. 2A, a resist layer 20 is formed on a master disk 19.

The master disk 19 is used for etching the surface to form a master disk. Here, a silicon wafer is used. The technology for etching a silicon wafer has been established in semiconductor device manufacturing technology, and high-precision etching is possible. The master base material 19 is not limited to a silicon wafer as long as it is a material that can be etched, and for example, a substrate or a film of glass, quartz, resin, metal, ceramic, or the like can be used.

As a material for forming the resist 20, for example, a commercially available positive type resist obtained by blending a diazonaphthoquinone derivative as a photosensitive agent with a cresol novolak resin, which is generally used in the manufacture of semiconductor devices, can be used as it is. . Here, the positive resist is a substance that can be selectively removed by a developer when exposed to radiation according to a predetermined pattern.

The method for forming the resist layer 20 is as follows.
Spin coating, dipping, spray coating,
It is possible to use a method such as a roll coating method and a bar coating method.

Next, as shown in FIG. 2B, a mask 21 is arranged on the resist layer 20, and only a predetermined area of the resist layer 20 is exposed to radiation 22 through the mask 21, An exposed area 23 is formed.

The mask 21 has a projection 13 shown in FIG.
The pattern is formed so that the radiation 22 is transmitted only in the region other than the region corresponding to the above.

The convex portions 13 are for transferring and forming ink-filled concave portions for forming the respective color pattern layers of the color filter to be manufactured, and are formed according to the shape and arrangement of the color pattern layers. It is formed. For example,
In a 10-inch VGA specification liquid crystal panel, 640 × 480 × 3 (color), 900,000 pixels, that is, about 900,000 convex portions 13 are formed on the master at a pitch of about 100 μm.

After the resist layer 20 is exposed to radiation 22 and then developed under predetermined conditions,
As shown in (c), only the resist in the radiation-exposed area 23 is selectively removed to expose the master matrix 19, and the other areas remain covered by the resist layer 20.

When the resist layer 20 is patterned in this manner, as shown in FIG. 2D, the master base material 19 is etched to a predetermined depth using the resist layer 20 as a mask.

As a method of etching, there is a wet method or a dry method. If an optimum method and conditions are selected from the viewpoint of the etching sectional shape, the etching rate, the in-plane uniformity, etc., in accordance with the material of the master base material 19. Good. In terms of controllability, the dry method is superior. For example, a parallel plate type reactive ion etching (RI
E) system, inductive coupling (ICP) system, electron cyclotron resonance (ECR) system, helicon wave excitation system, magnetron system, plasma etching system, ion beam etching system, etc. can be used. By changing the conditions such as the gas pressure and the bias voltage, the convex portion 13 can be etched into a desired shape, for example, processed into a rectangular shape, tapered, or roughened.

Next, after the etching is completed, the resist layer 20 is removed as shown in FIG.
A projection 13 is obtained on 9, and this is used as a master 12.

FIG. 1 shows the steps after the master 12 is obtained.

First, the master 12 is brought into close contact with a substrate via an ink-filled layer forming material.

As the substrate, a glass substrate is generally used. However, the substrate is not particularly limited as long as it satisfies the characteristics such as light transmittance and mechanical strength required for a color filter. A plastic substrate such as arylate, polyethersulfone, amorphous polyolefin, polyethylene terephthalate, polymethyl methacrylate, or the like, or a film substrate may be used. As the ink filling layer forming material,
The thickness of the colored pattern layer forming region 17 shown in FIG. 1E is not particularly limited as long as the colored pattern layer 16 has a light transmittance that does not impair the color characteristics.
Although various substances can be used, a substance which can be cured by applying energy is preferable. In such a case,
When forming the ink-filled layer, it can be handled in a low-viscosity liquid state, and the material for forming the ink-filled layer can be easily filled up to the fine portion of the concave portion on the master 12 even at normal temperature and normal pressure.

The energy is preferably light, heat, or both light and heat. By doing so, a general-purpose exposure apparatus, a baking furnace, and a hot plate can be used, and low equipment cost and space saving can be achieved.

As such a substance, for example, there is an ultraviolet curable resin. Acrylic resin is suitable as the UV-curable resin. By using various commercially available resins and photosensitizers, it is possible to obtain an ultraviolet-curable acrylic resin which is excellent in transparency and can be cured in a short time.

Specific examples of the basic composition of the ultraviolet-curable acrylic resin include a prepolymer or oligomer, a monomer, and a photopolymerization initiator.

As the prepolymer or oligomer,
For example, acrylates such as epoxy acrylates, urethane acrylates, polyester acrylates, polyether acrylates, and spiroacetal acrylates; methacrylates such as epoxy methacrylates, urethane methacrylates, polyester methacrylates, and polyether methacrylates; Is available.

As the monomer, for example, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, N-vinyl-2-pyrrolidone, carbitol acrylate, tetrahydrofurfuryl acrylate, isovol Monofunctional monomers such as nyl acrylate, dicyclopentenyl acrylate, and 1,3-butanediol acrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol diacrylate,
Bifunctional monomers such as neopentyl glycol dimethacrylate, ethylene glycol diacrylate, polyethylene glycol diacrylate, pentaerythritol diacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate,
Polyfunctional monomers such as pentaerythritol triacrylate and dipentaerythritol hexaacrylate can be used.

As the photopolymerization initiator, for example, 2,2-
Acetophenones such as dimethoxy-2-phenylacetophenone, butylphenones such as α-hydroxyisobutylphenone and p-isopropyl-α-hydroxyisobutylphenone, p-tert-butyldichloroacetophenone, p-tert-butyltrichloroacetophenone, α, halogenated acetophenones such as α-dichloro-4-phenoxyacetophenone, benzophenone,
Benzophenones such as N, N-tetraethyl-4,4-diaminobenzophenone; benzyls such as benzyl and benzyldimethylketal; benzoins such as benzoin and benzoin alkyl ether; 1-phenyl-1,2
Oximes such as -propanedione-2- (o-ethoxycarbonyl) oxime, 2-methylthioxanthone,
-Xanthones such as chlorothioxanthone, benzoin ethers such as benzoin ether and isobutyl benzoin ether, and radical generating compounds such as Michler's ketone can be used.

Incidentally, if necessary, a compound such as an amine or a solvent component may be added for the purpose of preventing curing inhibition by oxygen.

The solvent component is not particularly limited, and various organic solvents such as propylene glycol monomethyl ether acetate, propylene glycol monopropyl ether, methoxymethyl propionate, ethoxyethyl propionate, ethyl cellosolve, Ethyl cellosolve acetate, ethyl lactate,
One or more kinds selected from ethyl pyruvate, methyl amyl ketone, cyclohexanone, xylene, toluene, butyl acetate and the like can be used. Such an ultraviolet-curable acrylic resin 11 is used as shown in FIG.
As shown in the figure, a predetermined amount is dropped on the substrate 10.

Next, as shown in FIG.
Is adhered onto the substrate 10 via the resin 11 to spread the resin 11 to a predetermined region, and then irradiated with ultraviolet light from the substrate 10 for a predetermined time to cure the resin 11, and as shown in FIG. An ink filling layer 14 is formed between the substrate 10 and the master 12.

In spreading the resin 11 to a predetermined area, a predetermined pressure may be applied on the master 12 as needed.

In this case, the resin 11 is dropped on the substrate 10.
It may be dropped on both.

Also, a spin coating method, a dipping method,
The resin 11 may be applied to one or both of the substrate 10 and the master 12 by using a method such as a spray coating method, a roll coating method, or a bar coating method.

Then, as shown in FIG.
0 and the ink filling layer 14 are integrally peeled from the master 12 to obtain the substrate 10 on which the ink filling layer 14 having the ink filling recess 15 on the surface is formed.

When the ink filling recess 15 is formed on the substrate 10 in this manner, next, as shown in FIG.
Each of the ink filling recesses 15 is filled with a preset coloring ink to form a coloring pattern layer 16.

The method of filling the colored ink into the ink filling recess 15 is not particularly limited, but an ink jet method is preferable. According to the ink jet method, it is possible to fill the ink at high speed and economically without waste by applying the technology practically used for the ink jet printer.

FIG. 3 shows a state in which the ink filling recess 15 is filled with, for example, each color ink 26 of red ink R, green ink G and blue ink B by the ink jet head 25.

A head 25 is arranged so as to face the ink filling recess 15 on the substrate 10, and the colored ink 26 is discharged to each ink filling recess 15 by the head 25.

The head 25 has been put into practical use, for example, for an ink jet printer, and a piezo jet type using a piezoelectric element or a bubble jet type using an electrothermal converter as an energy generating element can be used. The coloring area and the coloring pattern can be set arbitrarily.

For example, this head 25 is driven at a driving frequency of 1
At 4.4 kHz (14,400 discharges per second), 20 discharge ports for each of R, G, and B are arranged for discharging ink, and three drops of ink are discharged to one ink filling recess 15. Then, the time required to fill the ink filling recess 15 for the color filter of the type 10 VGA of about 900,000 pixels with ink is 900,000 × 3 drops / (1440).
(0 times × 20 colors × 3 colors) = about 3 seconds. Here, even if the time for the head 25 to move between the ink filling recesses 15 is taken into consideration, all the ink filling recesses 15 can be filled with the coloring ink 26 in about 2 to 3 minutes.

When the coloring ink 26 contains a solvent component, it is subjected to a heat treatment to volatilize the solvent of the ink.

In this way, as shown in FIG. 1E, the colored pattern layer 16 is formed on the substrate 10, and a completed color filter product 18 is obtained.

In the above embodiment, the projection 13
In forming the resist, a positive resist was used, but the area exposed to the radiation became insoluble in the developer, and the area not exposed to the radiation could be selectively removed by the developer. A resist may be used. In this case, a mask whose pattern is inverted from that of the mask 21 is used. Alternatively, the resist may be directly exposed in a pattern by using a laser beam or an electron beam without using a mask.

(Second Embodiment) Next, FIGS.
FIG. 9 is a view showing a process of manufacturing a master according to the second embodiment of the present invention.

First, as shown in FIG. 4A, a resist layer 20 is formed on the second master 27.

The second master 27 serves as a support when the resist layer 20 is patterned by lithography, and has mechanical strength, chemical resistance, and the like necessary for process flow. The material is not particularly limited as long as it has good wettability and adhesion to the material forming the resist layer 20, and for example, a substrate made of glass, quartz, a silicon wafer, resin, metal, ceramic, or the like can be used. Here, a glass master disk is used in which the surface is polished flat using a cerium oxide-based abrasive, and then washed and dried.

As the material and the method for forming the resist layer 20, the same material and method as those described in the first embodiment can be used, and the description is omitted.

Next, as shown in FIG.
8 is disposed on the resist layer 20, and only a predetermined area of the resist layer 20 is exposed to the radiation 22 via the mask 28 to form a radiation-exposed area 23.

The mask 28 has a recess 29 shown in FIG.
Is formed in a pattern such that the radiation 22 is transmitted only in the region corresponding to

The concave portion 29 has a concave shape for forming a convex portion of the master. The convex portion of the master is formed by transferring an ink filling concave portion for forming a color pattern layer of a color filter. It is for doing. Therefore, the concave portion 29 has the same shape and arrangement as the ink filling concave portion, that is, is formed according to the shape and arrangement of the color pattern layer of the color filter to be manufactured.

Then, when development processing is performed under predetermined conditions after exposure to the radiation 22, only the resist in the radiation-exposed region 23 is selectively removed as shown in FIG. Patterning is performed, and a concave portion 29 is formed on the second master 27.

Next, as shown in FIG. 5A, a conductive layer 30 is formed on the resist layer 20 and the second master 27 to make the surface conductive.

The conductive layer 30 is made of, for example, Ni
What is necessary is just to form in the thickness of 00 to 1000 degrees. As a method for forming the conductive layer 30, a method such as sputtering, CVD, vapor deposition, or electroless plating can be used.

Further, the resist layer 20 and the second master 27 made conductive by the conductive layer 30 are used as a cathode, and chip-shaped or ball-shaped Ni is used as an anode.
Ni was further electrodeposited by electroplating, and FIG.
The metal layer 31 is formed as shown in FIG.

As the electroplating solution, for example,
A plating solution having the following composition can be used.

Nickel sulfamate: 900 g / l Boric acid: 60 g / l Nickel chloride: 8 g / l Leveling agent: 30 mg / l Next, as shown in FIG. After being peeled off from the second master 27, it is washed as necessary to make the master 12.

The conductive layer 30 may be removed from the metal layer 31 by performing a peeling treatment as needed.

When the master 12 is thus obtained, a color filter can be obtained by subsequently performing the steps shown in FIG.

Also in this embodiment, a negative resist may be used. In this case, the mask 28 is a mask whose pattern is inverted, that is, the mask 2 shown in FIG.
The same mask as 1 can be used. Alternatively, the resist may be directly exposed in a pattern by laser light or electron beam without using a mask.

According to the above-described color filter manufacturing method, once the master 12 is manufactured, it can be used as many times as the durability permits, so that it is omitted in the manufacturing process of the second and subsequent color filters. As a result, the number of steps and the cost can be reduced.

Thereafter, if necessary, a BM and an overcoat layer are formed on the colored pattern layer 16, a transparent electrode and an alignment film are attached, and the array is mounted.

[0083]

According to the method of manufacturing a color filter of the present invention, a photolithography step is performed in forming a concave portion for ink filling for forming a colored pattern layer on a substrate.
Since it is not necessary to perform the process for each sheet, it is possible to provide a very inexpensive and high-quality color filter, especially in combination with the ink jet method.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a process of manufacturing a color filter according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a process of manufacturing a master according to the first embodiment of the present invention.

FIG. 3 is a view showing a step of forming a colored pattern layer in the embodiment of the present invention.

FIG. 4 is a diagram illustrating a process of manufacturing a master according to a second embodiment of the present invention.

FIG. 5 is a diagram illustrating a process of manufacturing a master according to a second embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 substrate 11 resin (ink filling layer forming material) 12 master 13 convex portion 14 ink filling layer 15 ink filling concave portion 16 coloring pattern layer 17 coloring pattern layer forming region 18 color filter 19 master substrate 20 resist layer 21 mask 22 radiation 23 Radiation exposure area 24 Etchant 25 Ink jet head 26 Colored ink 27 Second master 28 Mask 29 Depression 30 Conducting layer 31 Metal layer

Claims (8)

[Claims] A first step of manufacturing a master having a plurality of convex portions arranged in a predetermined arrangement; and bringing the master into close contact with a substrate via an ink filling layer forming material, and solidifying the ink filling layer forming material to form an ink. A second step of transferring and forming an ink filling layer having a plurality of ink filling recesses on the substrate by integrally peeling the substrate and the ink filling layer from the master after forming the filling layer; A third step of forming a colored pattern layer by filling the ink filling concave portion with ink of a preset color. 2. The method for manufacturing a color filter according to claim 1, wherein in the first step, a resist layer according to a predetermined pattern is formed on the master base material, and then the resist layer is formed on the master base material by etching. Forming a convex part on the substrate to form a master. 3. The method for manufacturing a color filter according to claim 2, wherein said master substrate is a silicon wafer. 4. The method for manufacturing a color filter according to claim 1, wherein in the first step, a resist layer corresponding to a predetermined pattern is formed on a second master, and then the second master and a second master are formed. Forming a metal layer by electrodepositing a metal by an electroplating method, forming a metal layer, and then separating the metal layer from the second master and the resist layer to form a master. Manufacturing method of a color filter. 5. The method for manufacturing a color filter according to claim 1, wherein the ink-filled layer forming material used in the second step is a substance curable by application of energy. Method. 6. The method for manufacturing a color filter according to claim 5, wherein the energy is any one of light, heat, or both light and heat. 7. The method for manufacturing a color filter according to claim 6, wherein the ink-filled layer forming material is an ultraviolet curable resin. 8. The method for manufacturing a color filter according to claim 1, wherein said ink is filled by an ink jet method in said third step.