JPH10330662A - Ink for color filter and production of color filter with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink capable of being stably printed on a substrate to be printed in a prescribed amount, and to provide a method for producing a color filter, enabling to highly precisely and stably print the ink to form a colored pattern. SOLUTION: This ink 4 for color filters comprises a pigment, a phenoxy resin or an epoxy resin, a curing agent, and an organic solvent 8 and has a viscosity of 0.5-10 Pa.s. The concentration of the orgic solvent 8 in the ink 4 is set to 60-80 wt.%. This method for producing a color filter comprises charging the ink 4 into the pattern depressions 2 of a depressed plate 1, transferring the ink 4 in the pattern depressions 2 to a transfer member 7 having a mold release property to diffuse the organic solvent 8 in the ink 4 into the transfer member 7, printing the ink 4 on the transfer member 7 to a substrate 9 to be printed, and subsequently rolling the ink 4 on the substrate 9 with a rolling roll 1 having a mold release property.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a color filter ink mainly used as a constituent material of a color filter of a liquid crystal color display device, and a method of manufacturing a color filter using the same.

[0002]

2. Description of the Related Art Generally, a color filter of a liquid crystal color display device is formed by forming a light-shielding material such as chromium on a glass substrate and then forming a black matrix by a photolithography technique. Red, green, and blue colored patterns are formed in a predetermined arrangement in a plurality of the formed pixel regions, and the pixel regions are manufactured. Dyeing method, pigment dispersion method,
Electrodeposition or printing is employed.

In the dyeing method, a water-soluble resist such as gelatin having photosensitivity is applied to a glass substrate, a predetermined pattern is obtained by exposure and development, and a colored pattern is formed by dyeing and fixing. In the pigment dispersion method, a pigment is dispersed in a photoresist, a colored photoresist is applied to a glass substrate, and then a predetermined colored pattern is formed by exposure and development. In the electrodeposition method, patterning is performed by exposing a transparent conductive film on a substrate through a photomask, and a colored layer is formed by electrophoresis. In each of the above-described dyeing method, pigment dispersion method, and electrodeposition method, the above-described steps are repeated three times, respectively, to form red, green, and blue colored patterns, respectively.

On the other hand, as a printing method, a flat plate offset printing method or a concave plate offset printing method is mainly used. In the flat plate offset printing method, after the ink in the plate pattern portion is transferred to a rubber elastic body, the rubber elastic body ink is printed on a substrate to be printed. In the concave plate offset printing method, ink is filled into the concave portion of the concave plate pattern, excess ink is scraped off with a doctor blade, the ink in the concave portion of the pattern is transferred to a rubber transfer body, and then printed on the substrate to be printed I do. In any of the above printing methods, a predetermined coloring pattern is formed by sequentially printing each color ink of red, green, and blue one by one in a pixel array between black matrices on the same substrate to be printed in a predetermined arrangement. I do.

[0005]

However, among the above-described methods for producing a color filter, each means for forming a colored pattern by using a dyeing method, a pigment dispersing method, and an electrodeposition method, except for the printing method, is used. Since the photo process is repeated, a large number of large-sized exposure apparatuses are required to produce a large-area color filter, which causes a problem that not only the production cost is high but also the processing speed is low.

On the other hand, the manufacturing method of forming a colored pattern by using a printing method has a simpler process than the above-described means and reduces the manufacturing cost since there is no photo process in the manufacturing process. There are advantages that can be done. On the other hand, in the printing method, the thickness of the colored pattern tends to vary due to the viscosity of the ink and the like, and the ink protrudes from the pixel region to a part of the black matrix and a part of the line width of the black matrix. May become thinner. If the amount of ink to be printed on the substrate to be printed is set to be small to prevent this, a gap is formed between the printed ink and the black matrix. In any case, there is a problem that high-precision printing of the ink on the substrate to be printed cannot be performed stably.

Accordingly, the present invention provides a color filter ink that can always stably print a predetermined amount on a substrate to be printed and a color filter that can form a colored pattern by performing high-precision printing stably using the ink. It is intended to provide a manufacturing method.

[0008]

In order to solve the above problems, the color filter ink of the present invention comprises a pigment, at least one resin of a phenoxy resin or an epoxy resin, a curing agent, and an organic solvent. Containing
The organic solvent has at least one of cellosolve, cellosolve acetate, carbitol, carbitol acetate and ketone, and has a concentration in the ink of 0.5 Pa · s to 10 Pa · s. Is set to be 60 wt% to 80 wt%.

This ink for color filters has a viscosity lower than that which is generally considered to be appropriate when printing on a substrate to be printed.
Since the viscosity is set in the range of 5 Pa ・ s to 10 Pa ・ s, it is possible to fill the concave portion of the concave plate with good quantitativeness during the production of the color filter, and to remove the excess ink after scraping it with a doctor blade. The amount of unscraped residue on the surface of the plate is extremely small, and only a predetermined amount can be reliably filled. In addition, the organic solvent with excellent permeability is 60wt% ~ 80wt%
%, The organic solvent is diffused into the surface of the transfer member when the ink is transferred from the concave portion of the concave plate to the transfer member during the production of the color filter. As a result, the viscosity of the ink can be increased to a predetermined value suitable for printing on the substrate to be printed.

Further, the method of manufacturing a color filter according to the present invention includes an ink filling step of filling the color filter ink of the above invention into the pattern concave portions of the concave plate, and a mold releasing property of the color filter ink in the pattern concave portions. An ink transfer step of transferring to a transfer body having, and an ink viscosity increasing step of diffusing an organic solvent in the color filter ink transferred to the transfer body into the transfer body to increase the color filter ink to a predetermined viscosity. An ink printing step of printing the color filter ink on the transfer body onto the substrate to be printed; and an ink smoothing step of rolling the color filter ink on the substrate by a roll having releasability. doing.

In this method of manufacturing a color filter, the ink of the present invention is used, so that a predetermined amount of ink can be reliably filled in the concave portion in the ink filling step, and the pixel region between the black matrices can be filled in the ink transferring step. An amount of ink corresponding to the volume can be transferred to the transfer body, and in the ink printing process, the ink having the desired viscosity can be printed on the substrate to be printed at a transfer rate of almost 100% from the transfer body. Therefore, an amount of ink corresponding to the volume of the pixel region can be accurately printed on the substrate to be printed.

Further, in the smoothing step, the ink is crushed by a rolling roll to spread it in the pixel region without any gap, and the upper surface of the ink can be smoothed to a flat surface, so that a highly accurate colored pattern having a constant film thickness can be formed. In addition, since a predetermined amount of ink corresponding to the volume of the pixel area can always be printed on the substrate to be printed, the ink does not protrude from the pixel area to a part of the upper end surface of the black matrix, and the black matrix is formed. The line width at the time can be reliably maintained.
Further, since the colored pattern is formed using a printing method without a photo process, a color filter can be manufactured at low cost.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing each step of a method for manufacturing a color filter according to an embodiment of the present invention, (a) is an ink filling step, (b) is an ink transfer and ink viscosity increasing step,
(C) shows an ink printing step, and (d) shows an ink smoothing step.

First, the ink 4 as a constituent material of the color filter will be described. The color filter ink 4 used in this embodiment includes a pigment, a resin, a curing agent,
The viscosity is set to 0.5 Pa · s to 10 Pa · s by mixing with an organic solvent. The composition is 5 to 15 wt% of pigment, 10 to 30 wt% of resin, and 0.5 to 10 wt% of curing agent. It is contained in each range.

As the organic solvent, one having an excellent ability to dissolve the resin and having excellent permeability, for example, at least one or more of cellosolve, cellosolve acetate, carbitol, carbitol acetate and ketone solvents Is contained. This organic solvent is ink 4
It is contained in such an amount that the concentration in the medium becomes 60 wt% to 80 wt%. As the resin, at least one of a phenoxy resin and an epoxy resin excellent in durability, chemical resistance, heat resistance and the like required for this kind of color filter ink 4 is used.

In this embodiment, as the pigment,
CI.pigmentR177 and CI.pigment for red ink 4
Use a mixture of Y83 and C for green ink 4.
A mixture of I.pigmentG36 and CI.pigmentY86 is used. In the case of blue ink 4, CI.pigmentB15: 3 or
A mixture of CI.pigment B15: 6 and CI.pigment V23 is used. In addition, a blocked isocyanate is used as a curing agent.

Next, a method of manufacturing a color filter according to an embodiment of the present invention using the above-described color filter ink 4 will be described. In the ink filling step shown in FIG. 1A, after filling the ink 4 into the groove-shaped concave portion 2 formed on the concave plate 1, the excess ink 4 is scraped off by the doctor blade 3, and the fixed amount is Fill with ink 4. In this ink filling step, 0.5 Pa · s to 10 Pa · 10, which is lower than an appropriate viscosity when printing on the substrate 9 to be described later.
Since the ink 4 set to the viscosity in the range of s is used,
The ink 4 can be filled into the concave portion 2 of the concave plate 1 with good quantitativeness, and the surplus of the ink 4 on the surface of the concave plate 1 after the surplus ink 4 is scraped off by the doctor blade 3 is extremely small.

In other words, in the ink filling step, the ink 4 can always be reliably filled by a set constant amount. On the other hand, in the conventional printing method, ink set to a high viscosity suitable for printing on a substrate to be printed is applied to the concave portions 2
Therefore, the amount of ink 4 filled in the concave portion 2 varies, and the concave portion 1 after scraping by the doctor blade 3 has a residue of the ink 4 scraped off.

Next, in the ink transfer and ink viscosity increasing step (b), the surface of the roller 7a is covered with an elastic body 7b mainly composed of silicone rubber so that the transfer body 7 having releasability is formed into a concave plate. 1 and rotate in the direction of the arrow while pressing on the outer peripheral surface of the transfer body 7 that rolls on the concave plate 1.
The ink 4 in the concave portion 2 is transferred according to the interval between the concave portions 2, that is, the formation pattern of the concave portion 2. In this case, since the concave portion 2 is accurately filled with the predetermined amount of the ink 4 as described above,
A predetermined amount of the ink 4 is also transferred to the transfer body 7.

Further, after the transfer of the ink 4 to the transfer member 7, the organic solvent 8 in the ink 4 is set high so that the concentration in the ink 4 becomes 60 wt% to 80 wt%.
In addition, since the organic solvent 8 having excellent permeability is used, the organic solvent 8 is appropriately diffused into the elastic body 7b of the transfer body 7. As a result, the viscosity of the ink 4 increases from the viscosity in the range of 0.5 Pa · s to 10 Pa · s set in advance to a predetermined value suitable for printing on the substrate 9 to be printed.

In the ink printing step (c), the transfer body 7 to which the ink 4 has adhered is rotated in the direction of the arrow while pressing the transfer body 7 onto the substrate 9 to be printed. Print. Here, the substrate to be printed 9 has a configuration in which a light-shielding material such as chromium is formed on a glass substrate, and then a black matrix 10 is formed in advance by a photolithography technique.
The pixel region 12 is provided between 0s. The thickness of the black matrix 10 is formed to be slightly larger than that of a conventional printing substrate for a color filter. The ink 4 is printed on the printed substrate 9 from the transfer body 7 in the same pattern as the formation pattern of the concave portion 2 of the concave plate 1, and every third pixel region 1 of the color on the printed substrate 9 is printed.
2 are sequentially printed.

In the ink printing step, the ink 4 is increased to a viscosity suitable for printing, and the transfer member 7 has releasability. The ink 4 can be printed on the substrate 9 with a transfer rate of almost 100%. However, the volume of the pixel area 12 is slightly larger than the conventional one because the thickness of the black matrix 10 is formed slightly larger than the conventional one. There is a gap between the black matrix 10. This gap is corrected in the next ink smoothing step.

In the ink smoothing step (d), the roll 11 having releasability is rotated in the direction of the arrow while maintaining the position in contact with the upper end surface of the black matrix 10 on the substrate 9 to be printed. The black matrix 10 is rolled. Thereby, the ink 4 on the substrate 9 to be printed is
The upper part of the black matrix 1
The colored pattern 13 spreads without gaps in the pixel region 12 between zero and the upper surface is smoothed to an accurate flat surface, and a highly accurate colored pattern 13 is formed. By repeating the above ink filling step, ink transfer and ink viscosity increasing step, ink printing step and ink smoothing step three times, each of the red, green and blue colored patterns 13 is formed,
The color filter is completed.

In the method of manufacturing a color filter according to this embodiment, a predetermined amount of the ink 4 can be reliably filled in the concave portion 2 in the ink filling step (a), and the ink transfer and ink viscosity increasing step (b). In addition, the amount of the ink 4 corresponding to the volume of the pixel region 12 between the black matrices 10 can be reliably transferred to the transfer member 7, and the viscosity of the ink 4 can be increased to a desired value. The ink 4 of the transfer body 7 can be printed on the substrate 9 at a transfer rate of almost 100%. for that reason,
Since the amount of the ink 4 corresponding to the volume of the pixel region 12 is accurately printed on the substrate 9 to be printed, the ink 4 crushed by the roll 11 overlaps a part of the upper end surface of the black matrix 10. Does not occur. Therefore, the upper end surface of the black matrix 10 surely maintains the line width when it is formed.

Further, in this method of manufacturing a color filter, the colored pattern 13 is formed by using a printing method without a photo process, and the printing method is almost the same as the printing method used for manufacturing a conventional color filter. Process. Therefore, the color filter can be manufactured with high precision and at low cost.

[0026]

According to the ink for a color filter of the present invention, the viscosity is set in the range of 0.5 Pa · s to 10 Pa · s, which is lower than the viscosity which is usually considered appropriate when printing on a substrate to be printed. In the production of the color filter, the concave portion of the concave plate can be filled with a good quantitative property, and the amount of unscraped residue on the surface of the concave plate is extremely small, so that only a certain amount can be reliably filled. Also, since the organic solvent was set at a relatively high concentration of 60 wt% to 80 wt%, the organic solvent diffused into the surface of the transfer body when the ink was transferred to the transfer body during the production of color filters. Then, the viscosity of the ink can be increased to a predetermined value suitable for printing on the substrate to be printed.

According to the method of manufacturing a color filter of the present invention, by using the ink of the present invention, it is possible to accurately print an amount of ink corresponding to the volume of the pixel area between the black matrices on the substrate to be printed. Since the ink on the substrate to be printed can be crushed by a rolling roll and spread in the pixel area without any gap, the upper surface of the ink can be smoothed to a flat surface, so that a highly accurate coloring pattern having a constant film thickness can be formed. The black matrix can be reliably maintained at the line width at the time of formation. Further, since the colored pattern is formed using a printing method without a photo process, a color filter can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing each step of a method of manufacturing a color filter according to an embodiment of the present invention, in which (a) is an ink filling step, (b) is an ink transfer and ink density setting step, (C) is an ink printing step, and (d) is an ink smoothing step.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 concave plate 2 pattern concave portion 4 ink for color filter 7 transfer member 8 organic solvent 9 substrate to be printed 10 black matrix 11 rolling roll 13 coloring pattern

Claims (2)

[Claims] 1. A composition comprising a pigment, at least one resin selected from a phenoxy resin and an epoxy resin, a curing agent, and an organic solvent, wherein the viscosity is set to 0.5 Pa · s to 10 Pa · s; The solvent has at least one of cellosolve type, cellosolve acetate type, carbitol type, carbitol acetate type and ketone type, and is contained so as to have a concentration in the ink of 60 wt% to 80 wt%. An ink for a color filter, characterized in that: 2. An ink filling step of filling the color filter ink according to claim 1 into a pattern concave portion of a concave plate, and an ink for transferring the color filter ink in the pattern concave portion to a transfer member having releasability. A transfer step; an ink viscosity increasing step of diffusing an organic solvent in the color filter ink transferred to the transfer body into the transfer body to increase the color filter ink to a predetermined viscosity; and a color filter on the transfer body. A color filter comprising: an ink printing step of printing ink for printing on a substrate to be printed; and an ink smoothing step of rolling the ink for a color filter on the substrate to be printed by a roll having releasability. Manufacturing method.