JP4433244B2 - Manufacturing method of color filter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of color filters used for liquid crystal color displays and the like, and particularly relates to a technique for producing a color filter by applying colored ink on a substrate in a line shape by an ink jet method. .
[0002]
[Prior art]
The color filter for liquid crystal has a structure in which pigments of three colors of red, green, and blue are arranged in a mosaic or stripe pattern on a transparent substrate such as glass, and each boundary is partitioned by a black matrix. At present, the pigment dispersion method is the main method for producing this color filter. In this method, first, a red, green, or blue photoreactive resist ink is applied on the entire surface of a glass substrate on which a black matrix is formed, and then only a portion where the applied colored layer is to be formed by mask exposure. Is cured and an unnecessary part is removed by a development process to form a colored layer of the first color, but the same process is repeated three times to obtain three colors of red, green, and blue. Therefore, since the number of steps is large and the resist ink is almost wasted by development, a low-cost and highly efficient color filter manufacturing method is desired. In view of this, a color filter manufacturing method based on an inkjet method has already been proposed in Japanese Patent Application Laid-Open No. 59-75205 as a low-cost and simple color filter manufacturing method.
[0003]
This inkjet filter manufacturing method uses an inkjet head having a plurality of orifices, and discharges colored ink while moving the inkjet head relative to the substrate to apply the ink to the substrate in a line. FIG. 1 shows a schematic diagram of a three-color simultaneous coating method which is a method for forming a colored layer by using a coating apparatus incorporating this inkjet head.
[0004]
In FIG. 1, G is a substrate to be coated placed on the stage S. By moving a coating apparatus having a plurality of inkjet heads relative to the substrate G, colored ink is formed in a line shape. It is comprised so that it may apply | coat to. That is, the left eight inkjet heads Hr eject red colored ink, and are attached to a frame (not shown) so that a plurality of orifices in each inkjet head Hr are continuous in the width direction of the substrate G. . Similarly, the eight coating heads Hg at the center eject green colored ink and are attached to a frame (not shown) so that a plurality of orifices in each inkjet head Hg are continuous in the width direction of the substrate. . Similarly, the right eight inkjet heads Hb eject blue colored ink, and are attached to a frame (not shown) so that a plurality of orifices in each inkjet head Hb are continuous in the width direction of the substrate. Yes. Therefore, the respective ink jet heads move integrally with the substrate while discharging the colored ink from the plurality of orifices, so that the three colored inks are applied in a single application process.
[0005]
As a method for producing a color filter by the ink jet method, three methods are roughly classified.
[0006]
The first method is proposed in Japanese Patent Laid-Open No. 9-203803. This method is a method of providing a partition wall. In this system, first, as shown in FIG. 2A, a partition wall 12 made of a line-shaped resin black matrix is formed on a substrate 11, and a water repellent treatment or the like is applied to an upper portion 12a of the partition wall 12. Then, as shown in FIG. 2B, colored ink 14 is applied from the inkjet head 13 into the partition wall 12. Since the colored ink 14 is prevented from diffusing by the partition walls 12, a colored layer 15 is formed between the partition walls 12 on the substrate 11 as shown in FIG.
[0007]
The second method is proposed in Japanese Patent Laid-Open No. 8-230314. This method is a method of providing an absorption layer. In this method, first, as shown in FIG. 3A, a linear resin black matrix 22 is formed on a substrate 21, and an ink absorption layer 23 is formed so as to cover it. Next, as shown in FIG. 3B, exposure is performed through a mask 24 to cure the upper portion 23a of the black matrix 22 to eliminate absorption, and as shown in FIG. The colored ink 26 is applied from 25 to the ink absorbing layer 23. Since the colored ink 26 soaks into the ink absorbing layer 23, a colored layer 27 is formed between the black matrices 22 on the substrate 21.
[0008]
Since these first and second methods have advantages and disadvantages, the present inventors have already proposed a method such as JP-A-11-337726 as the third method.
[0009]
This third method is a photocatalytic method. In this method, first, as shown in FIG. 4A, a chromium black matrix 32 is formed on a substrate 31, and a photocatalyst containing layer 33 in which titanium oxide is dispersed in a silicone resin is formed thereon as a photocatalyst. The photocatalyst-containing layer 33 has a function of decomposing the organic group in the exposed portion by the decomposition action of the photocatalyst and reducing the ink repellency of this portion. Next, as shown in FIG. 4B, only the portion 33a where the colored layer is formed is subjected to mask exposure through the mask 34, and then, as shown in FIG. When 36 is applied, the colored ink wets and spreads only on the exposed portion with the unexposed portion as a boundary due to the ink repulsion of the unexposed portion. The colored layer 37 can be formed by drying and curing this. The unexposed portion is formed between the pixels, that is, on the black matrix 32 in order to prevent wetting and spreading of the colored ink to the adjacent pixels. Preferably, a range narrower than the width of the black matrix 32 is defined as the unexposed portion. However, a more uniform colored layer can be formed. As the coloring ink, both water-based and solvent-based inks can be used, and preferable solvents include propylene glycol monoethyl ether acetate as a main component, and butyl carbitol acetate for improving ink resilience. The main ink is used. As the colorant, any of dyes and pigments can be used.
[0010]
[Problems to be solved by the invention]
By the way, when forming the colored layer of the color filter by the ink jet method described above, it is usually necessary to apply colored ink to 1000 or more stripe patterns for each of the RGB colors. In view of productivity, it is desirable to use a large inkjet head having a large number of channels. However, if such a large inkjet head is to be manufactured, the yield is low and the cost is high, which is not practical. Further, in the method of combining a plurality of inkjet heads with a small number of channels as in the coating apparatus shown in FIG. 1, it is necessary to adjust the mounting position and the mounting angle of each inkjet head for each item, and these There is a problem that it takes a lot of time to adjust.
[0011]
The present invention has been made in view of such a background, and an object of the present invention is to produce a large-sized ink jet when producing a color filter by applying a colored ink to a substrate with a black matrix by an ink jet method. It is an object of the present invention to provide a method for manufacturing a color filter in which colored ink can be dropped onto a substrate with the same number of orifices as a head.
[0012]
[Means for Solving the Problems]
The method for producing a color filter according to claim 1 uses an inkjet head having a large number of orifices, and applies colored ink from the orifices onto the substrate while moving the substrate relative to the inkjet head. In the method of manufacturing a color filter including the step of coloring a specific portion of the substrate in a pattern, a head unit integrated with an orifice plate by combining a plurality of head modules having a predetermined number of channels as the inkjet head. It is characterized by use.
[0013]
A color filter manufacturing method according to a second aspect of the present invention is the color filter manufacturing method according to the first aspect, wherein the plurality of head modules are arranged in a direction perpendicular to the relative movement direction of the substrate. It is characterized by being combined with an integer multiple of the pixel pitch.
[0014]
A color filter manufacturing method according to a third aspect of the present invention is the color filter manufacturing method according to the first aspect, wherein the plurality of head modules are arranged in a direction perpendicular to the relative movement direction of the substrate (color filter). The pixel pitch is multiplied by an integral multiple of (number of channels) × (number of channels).
[0015]
A color filter manufacturing method according to a fourth aspect of the invention is characterized in that, in the color filter manufacturing method according to the second or third aspect, the orifices of all the combined head modules are arranged in a line. Yes.
[0016]
The color filter manufacturing method according to claim 5 is the color filter manufacturing method according to any one of claims 1 to 4, wherein the head unit includes a plurality of head modules and a plurality of color ink supply systems. It is characterized by becoming.
[0017]
A color filter manufacturing method according to a sixth aspect of the present invention is the color filter manufacturing method according to any one of the first to fifth aspects, wherein the orifice plate is made of a single plate.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
[0019]
FIG. 5 is a perspective view for explaining the head unit used in the present invention. The principle of the ink jet method is that an electric field is applied to the piezo element 1 to expand and contract in the direction of the arrow, and when the piezo element 1 is extended, the colored ink is pushed out from the ink flow path 2 to form the micropores formed below the ink flow path 2. In this method, the colored ink 3 is ejected from the orifice. An ordinary inkjet head has a predetermined number of channels corresponding to the orifices. The head unit shown in FIG. 5 has two head modules A and B each having a predetermined number of channels. The ink flow paths 2 are designed so that the orifices 4 are arranged in a line as shown in the bottom view of FIG. In order to obtain such a structure, the flow path plate and the orifice plate are each manufactured as an integral type, and a plurality of head modules are assembled side by side, and the orifices 4 are arranged in a row by adjacent head modules.
[0020]
FIG. 7 illustrates the case where the orifices are not aligned. In FIG. 7A, the circle indicates the orifice 4, and indicates the joint portion between the right end of the head module A and the left end of the head module B. When the orifices 4 are not arranged in a row as described above, when the mounting angle of the head unit is changed in order to adjust the pitch of the orifices 4 according to the type of color filter to be manufactured, as shown in FIG. The pitch P ₁ at the boundary between the orifices 4 in the head modules A and B is slightly changed with respect to the pitch P ₀ of the orifice 4 and the continuity is lost, and the colored ink is applied along the stripe pattern. I can't do that.
[0021]
As another form of the head unit used in the present invention, as shown in FIG. 8A, the head modules A and B may be combined in a line with an orifice interval W ₀ at both ends thereof. This has the advantage that the head modules do not interfere with each other during assembly. Further, since the orifices 4 of the head modules A and B are positioned on the same straight line, the continuity of the pitch of the orifices 4 can be maintained even when the head modules A and B are inclined as shown in FIG. In order to manufacture such head units A and B, a plurality of piezo modules and one orifice plate may be integrated, and a plurality of these may be attached to another substrate, or an orifice The plate and / or the flow path plate may be a common integrated type, and a plurality of piezo modules may be combined therewith.
[0022]
As another form of the head unit used in the present invention, as shown in FIG. 9, a plurality of head modules A, B, and C are combined in a state where the angle is adjusted in accordance with the pitch of the color filter to be manufactured. You may do it. In this case as well, a plurality of piezo modules can be combined with the same orifice plate or the like, or the orifice plate and / or the flow path plate can be made into a common integrated type, and a plurality of head modules can be formed therewith. Can also be combined.
[0023]
When a head unit is configured by combining a plurality of head modules with the angle adjusted, three colors are shifted by the line pitch P _C of the color filter as shown in FIG. The head modules A, B, and C may be combined. In this case, the head unit can also be configured to include three head modules and three color ink supply systems corresponding to them.
[0024]
【The invention's effect】
As described above, the present invention uses an inkjet head having a large number of orifices, applies a colored ink from the orifices onto the substrate while moving the substrate relative to the inkjet head, and a specific portion of the substrate. In the method of manufacturing a color filter including the step of coloring the pattern into a pattern, a head unit integrated with an orifice plate by combining a plurality of head modules having a predetermined number of channels is used as the inkjet head. This makes it possible to easily make a head unit equivalent to a large inkjet head. By using this head unit, when the color filter items are different, the stripe pattern can be used without having to adjust the inkjet head. Coloring in according to It is possible to perform the application.
[Brief description of the drawings]
FIG. 1 is a schematic view of a three-color simultaneous coating method performed using a coating apparatus incorporating an inkjet head.
FIG. 2 is an explanatory diagram showing one method for forming a colored layer on a substrate by discharging colored ink from an inkjet head.
FIG. 3 is an explanatory diagram showing another method for forming a colored layer on a substrate by discharging colored ink from an inkjet head.
FIG. 4 is an explanatory view showing still another method for forming a colored layer on a substrate by discharging colored ink from an inkjet head.
FIG. 5 is a perspective view for explaining a head unit used in the present invention.
6 is a bottom view of FIG. 5. FIG.
FIG. 7 is an explanatory view exemplifying a case where orifices are not arranged in a line.
FIG. 8 is an explanatory diagram showing another form of the head unit used in the present invention.
FIG. 9 is an explanatory view showing still another embodiment of the head unit used in the present invention.
FIG. 10 is an explanatory view showing still another embodiment of the head unit used in the present invention.
[Explanation of symbols]
A, B, C Head module 1 Piezo element 2 Ink flow path 3 Colored ink 4 Orifice 11 Substrate 12 Partition 13 Inkjet head 14 Colored ink 15 Colored layer 21 Substrate 22 Black matrix 23 Ink absorbing layer 24 Mask 25 Inkjet head 26 Colored ink 27 Colored layer 31 Substrate 32 Black matrix 33 Photocatalyst layer 34 Mask 35 Inkjet head 36 Colored ink 37 Colored layer

Claims (6)

A color including a step of using an inkjet head having a large number of orifices, applying a colored ink from the orifice onto the substrate while moving the substrate relative to the inkjet head, and coloring a specific portion of the substrate in a pattern. In the filter manufacturing method, a head unit in which a plurality of head modules each having a predetermined number of channels are combined and integrated with an orifice plate is used as the ink jet head. 2. The method of manufacturing a color filter according to claim 1, wherein the plurality of head modules are combined while being shifted by an integral multiple of the pixel pitch of the color filter in a direction perpendicular to the relative movement direction of the substrate. A method for manufacturing a color filter. 2. The method of manufacturing a color filter according to claim 1, wherein the plurality of head modules are combined with a shift of an integral multiple of (color filter pixel pitch) × (number of channels) in a direction perpendicular to the relative movement direction of the substrate. A method for producing a color filter, characterized by comprising: 4. The method for manufacturing a color filter according to claim 2, wherein the orifices of all the combined head modules are arranged in a line. 5. The method for producing a color filter according to claim 1, wherein the head unit comprises a plurality of head modules and a plurality of color ink supply systems. 6. The method for manufacturing a color filter according to claim 1, wherein the orifice plate is a single plate.

Images