JP2007095630A - Ink discharge printed material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide ink discharge printed material with improvement both in mixing of colors and void failure in providing ink films in many regions when a supporting substrate is sectioned into the many regions by partitions in an ink discharge method. <P>SOLUTION: The ink discharge printed material is provided with the supporting substrate, the partitions sectioning the supporting substrate into many regions and the ink film discharged and formed on the many regions by using an ink discharging apparatus. The problems are solved by making a cross section of the partition in a normal line direction of the supporting substrate to be in an inverted "H" shaped configuration. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an ink discharge printed matter in which an ink film is formed in a partition wall and a region between the partition walls on a support substrate.
As the ink film of this printed matter, the color layer of the color filter, the color conversion layer of the color conversion filter, the light emitting medium layer of the EL element, the circuit pattern of the circuit board, the wiring pattern of the thin film transistor, the lens pattern of the microlens, the flow of the biochip A road pattern etc. can be mentioned.

There is a color display filter as a specific example of the printed matter on which the ink film is formed, and there are various color filters for this color display device. Here, the color liquid crystal and the color filter for the display are representative examples of the printed matter. Will be described.
Color liquid crystal displays are being used in a wide range from small-area displays such as watches and cameras to large-area displays such as computer terminal display devices and television image display devices. In recent years, color displays have been developed mainly for large-area applications. Is progressing rapidly.
Color filters are indispensable for the color display of liquid crystal displays, and are important components that determine the performance of color liquid crystal displays, and are used in various forms that are finely patterned to display high-definition images. It has been.

Conventionally, a photolithographic method using a photoresist material has been employed for manufacturing a color filter for a liquid crystal display device. As a general method of this photolithography method, a photoresist is spin-coated on a substrate, a photoresist layer having a uniform thickness is formed on the substrate, and exposed and developed in a predetermined shape.
However, when this spin coating is used and the photoresist is coated, a lot of photoresist is not used, and it is discarded at this point, and there is a problem that this photoresist material cannot be used economically.
In addition, since images are formed through processes such as exposure and development for each color, the overall work efficiency is low, and expensive optical equipment such as an exposure device and a development device is required. It was difficult to supply a stable product.

Therefore, in recent years, it has been proposed to form a colored layer of a color filter by an ink jet method.
When forming a color filter by this ink-jet method, the color filter is generally formed by discharging ink of three colors of RGB. When forming a colored layer by the ink jet method, the color droplet diameter is about several tens of μm, and the color filter pixel size is one pixel with a short side of several tens of μm and a long side of several hundreds of μm. It is.

For this reason, a light-shielding BM pattern is formed in advance on the substrate as a convex portion that acts as a weir for colored droplets flying by the ink jet method, and colored droplets of a specific color are placed in the pixel compartment. By spreading, a pixel in which a uniform colored layer is formed can be obtained.

As one of the problems in the ink jet method, there are problems such as “mixed color” and “white spot”. Hereinafter, these problems will be described by taking the production of a color filter in the ink jet method as an example.

“Mixed color” is a defect that occurs when inks are mixed between adjacent pixels (colored portions) of different colors, and colored inks of different colors are mixed (see FIG. 2).
Further, “missing white” is a defect that occurs due to the fact that the applied ink cannot spread sufficiently and uniformly in the region surrounded by the partition walls (see FIG. 3).
These defects cause display defects such as color unevenness and a decrease in contrast in the color filter.

In the method of manufacturing a color filter in which the black matrix is used as a partition and ink is applied to the opening area of the black matrix to form a colored portion, the volume of the opening area of the black matrix is several times to several tens of times. It is necessary to apply an ink having a double volume (see FIG. 1).
Here, when the solid content concentration of the colorant or the effective component contained in the ink is high, that is, when the volume of the applied ink is relatively small, the black matrix sufficiently functions as a partition, and the black matrix Since the ink can be held in the opening region of the ink, the applied ink does not cross over the black matrix and reach the adjacent colored portions of different colors.
However, when the solid content concentration in the ink is low, that is, when it is necessary to apply a large amount of ink, the ink overflows beyond the black matrix serving as the partition wall, so that color mixing occurs between adjacent colored portions. Will occur. In particular, since there is a limit to the viscosity of ink that can be stably ejected from the nozzles of an ink jet head, a technique for avoiding color mixing is necessary.

Therefore, even when an amount of ink far exceeding the height of the partition wall is given by imparting water and oil repellency to the black matrix, the surface layer of the partition wall is repelled because it exhibits ink repellency. The mixed color can be effectively prevented without extending to the adjacent colored portion beyond the partition wall.

However, when the upper surface of the black matrix also serving as the partition has ink repellency, the applied ink is held in the opening of the black matrix and does not reach the adjacent colored portion. However, if the ink repellency on the upper surface of the black matrix is low, the applied ink may spread over the black matrix and mix with the ink applied to the adjacent openings.

On the other hand, if the ink repellency is strong, the ink cannot be spread sufficiently and uniformly between the partition walls, resulting in white spots, thus sufficiently solving both the problems of mixed colors and white spots. It couldn't be said.
As a means for solving the above problem, a method has been proposed in which the shape of the black matrix is an inversely tapered structure (see Patent Document 1).
By using the partition walls described in Patent Document 1, color mixing and white spots derived from the above can be prevented, but the contact area between the support substrate and the partition walls becomes extremely small, and the partition walls are supported particularly in complicated patterns. Adhesiveness with the substrate cannot be sufficiently maintained, and defects such as breakage of partition walls may occur, and a secondary problem that defects such as color mixing may occur due to defects in the partition walls.
JP 2002-62422 A

The present invention has been created in view of the above circumstances, and the problem is that the support substrate is divided into a plurality of regions by partition walls by an ink ejection method, and an ink film is provided in the plurality of regions. It is an object of the present invention to provide an ink discharge printed matter that improves both color mixing and white spot defects.

The invention according to claim 1 is an ink discharge printed matter having a support substrate, a partition wall that divides the support substrate into a plurality of regions, and an ink film that is formed by discharge using an ink discharge device in the plurality of regions. ,
The partition wall is an ink-discharge printed matter, wherein a cross section in a normal direction of the support substrate has a letter-shaped shape.

The invention according to claim 2 is the ink ejection printed matter according to claim 1, wherein the partition has ink repellency.

According to a third aspect of the invention, there is provided the ink ejection printed matter according to the second aspect, wherein the partition wall has a smaller side ink repellency than an upper surface ink repellency.

According to a fourth aspect of the present invention, there is provided the ink ejection printed matter according to any one of the first to third aspects, wherein the partition is a light shielding layer including a black light shielding material.

According to a fifth aspect of the present invention, the support substrate is a transparent substrate, the ink film is an ink-formed colored layer containing an organic light emitting material, and a color filter having a plurality of colored layers. An ink-discharge printed matter according to any one of claims 1 to 4.

The invention according to claim 6 is an organic electroluminescent device in which the support substrate is a transparent substrate, the ink film is an organic light emitting layer formed with an ink containing an organic light emitting material, and an organic light emitting layer having a plurality of colors is provided. It is an ink discharge printed matter in any one of Claims 1 thru | or 4 characterized by the above-mentioned.

According to the present invention, when an ink film is formed in a region divided between partition walls by an ink ejection method, the shape of the partition wall is made into a letter-shaped shape, and ink repellency is provided to prevent poor color mixing and white spots. I was able to prevent it.

In particular, by reducing the ink repellency of the side surface compared to the upper surface of the partition wall, even if the ink film was formed by the ink ejection method, it was possible to obtain a printed matter with no color mixing failure or white spot failure. .

Hereinafter, the ink discharge printed matter having the ink film in the present invention will be described.
First, as shown in FIG. 4, the printed matter of the present invention is provided with a partition wall 2 that divides the support substrate 1 into a plurality of regions on the support substrate 1.
The partition wall 2 has ink repellency, and the cross section in the normal direction of the support substrate 1 has a letter-shaped shape, that is, has a recess on the side wall of the partition wall.
Both the lower surface 3 in contact with the support substrate 1 and the upper surface 4 of the partition wall 2 opposite to the support substrate 1 of the partition wall 2 have an acute corner 5 on the partition wall 2 side with respect to the support substrate surface 1. It is formed as follows.
And the ink discharge printed matter is obtained by forming the ink membrane | film | coat 6 in the area | region enclosed by the said partition 2 by the system which discharges ink.

As for the said partition 2, as shown in FIG. 5, about the cross-sectional structure of the partition 2, the angle of each corner | angular part A, B, C, D of the corner 5 in a figure is 90 degrees C or less The angles of the corners A, B, C, and D are not necessarily the same.
Note that the corners A, B, C, and D may have a rounded shape instead of a shape with the tip protruding at an acute angle.
Further, the angle of the corner 5 may be freely changed according to the type of ink, the pattern shape of the black matrix, the strength of ink repellency, and the like.

Furthermore, the length of the upper side E and the lower side F in the figure need not be the same for the partition 2, and the length of the lower side F is the adhesion between the support substrate 1 and the partition 2, the type of ink, and the black matrix pattern. It may be changed freely depending on the shape and strength of ink repellency.

In the present invention, since the cross section of the partition wall 2 is shaped like a letter having a recess 7 on the side, the ink ejected from the ink ejection device to the region in the partition wall 2 exceeds the partition wall 2. Since it is more stable to flow into the concave portion 7 of the kanji-shaped partition wall, ink does not flow out from the partition wall 2 and the ink film 6 is formed in each region in the partition wall 2 to suppress color mixing. It is done.

At this time, as the partition wall 2, for example, when the partition wall is a black matrix containing a light-shielding material and an ink repellent such as a fluorine compound is kneaded into the resin, the entire partition wall 2 has ink repellency. If the ink repellency is strong, white spots are likely to occur. However, in the case of the partition wall having the above-mentioned character shape structure, the partition wall 2 and the ink are separated by the ink repellency in the vicinity of the partition wall 2. Even if a gap is generated between the films 6, the ink can be spread along the support substrate 1, so that the occurrence of white spots can be suppressed.

In particular, for example, when the partition wall 2 is subjected to plasma treatment with a fluorine compound or the like in order to make the ink repellency appear after providing the partition wall 2 on the support substrate 1 so as to be divided into a large number, In addition, the partition upper surface 4 having a large area becomes a shadow of the side wall of the partition wall with respect to the plasma, and the degree of treatment of the partition wall side surface is lower than that of the partition wall upper surface 4, and as a result, the ink repellency of the partition wall side surface is lowered. it can.
Thereby, compared with the conventional forward taper shape or the conventional square or rectangular partition, the occurrence of white spots is suppressed. Further, since the upper surface of the partition wall 2 exhibits sufficient ink repellency, color mixing is also prevented at the same time.

The solution to the problem of imparting ink repellency to the upper surface 4 of the partition wall can be solved by a partition wall having a reverse taper structure. However, in the partition wall having a reverse taper structure, the contact area between the support substrate 1 and the partition wall 2 becomes very small. In a complicated pattern, the adhesion to the support substrate 1 cannot be maintained, and defects such as breakage of the partition walls 2 occur, and defects such as color mixing occur due to defects in the partition wall layer 2.
However, according to the present invention, the contact area of the support substrate 1 and the partition wall 2 is equal to that of the partition substrate 2 by forming the partition wall 2 in a shape having a concave portion on the side portion. Can be maintained.
As described above, by adopting the above-described configuration, defects such as breakage of the partition walls 2 can be suppressed, and defects such as color mixing caused by the defects of the partition wall layer 2 can be avoided.

Here, specific materials and methods of the present invention will be specifically described.
Specifically, the support substrate 1 of the present invention can be made of a material such as a glass substrate, a quartz substrate, or a plastic substrate, or a flexible material such as a plastic film as the support substrate.

The partition wall 2 of the present invention divides the surface of the support substrate into a large number of areas and prevents color mixing of the ink ejected into each of the large number of areas. In order to prevent this color mixture, the critical surface tension of the partition walls is preferably in the range of 24 to 30 mN / m.
When the material which comprises the said partition 2 contains an ink repellent agent, it consists of the component which contained the ink repellent agent in the resin composition and the resin binder.
The resin binder fixes the partition wall to the support substrate and imparts ink resistance to the partition wall, and is preferably a resin containing an amino group, an amide group, a carbosyl group, or a hydroxyl group.
Specific examples include a cresol-novolak resin, a polyvinylphenol resin, an acrylic resin, and a methacrylic resin. These resins may be used alone or in combination of two or more.

Next, the ink repellent agent imparts ink repellency to the partition walls and includes a fluorine-containing compound or a silicon-containing compound. The ink repellent agent is preferably mixed in the range of 0.01 to 10% by weight with respect to the resin composition.
Moreover, in order to provide light-shielding property, a black light-shielding material can be contained in the partition wall. Thus, the light-shielding partition can improve the contrast of the display image.
As this black light-shielding material, black pigment, black dye, carbon black, aniline black, graphite and the like can be used.
The ink is obtained by diluting the above material in a solvent, and is used by adjusting it in the range of 50 to 97% by weight with respect to the total weight of the resin composition.

Representative examples of the method for forming the partition include a printing method and a photophysographic method.
First, in order to form a partition by a printing method, a predetermined partition material is formed on a support substrate by forming a partition having a predetermined pattern shape and then heat-curing the partition. At this time, the material is selected so that the critical surface tension is in the range of 24 to 30 mN / m.
In addition, in order to form the partition by the photophysographic method, the photosensitive resin composition is uniformly applied on the support substrate to provide a resin layer, and then the mask is formed with a predetermined pattern through the mask. By exposing and developing the resin layer, partition walls having a predetermined pattern shape are formed. Further, heat treatment may be performed.
At this time, the material is selected so that the critical surface tension is in the range of 24 to 30 mN / m.

An explanation will be given of forming an ink film by ink ejection in a region divided by the partition walls formed in this way.
As an ink discharge device, there are a piezo method and a heat exchange method depending on the discharge method, and the piezo method is particularly preferable. An ink particle frequency is in a range of 5 to 100 KHz, a nozzle diameter is in a range of 5 to 80 μm, and a device in which a number of nozzles are incorporated in one head and a number of these heads are arranged is used.

An example of a color filter of a liquid crystal display device will be described.
When the ink film is a colored layer of a color filter, the ink material constituting the colored layer is composed of a color pigment, a resin, a dispersant, a solvent, and the like.
Specific examples of the color pigment include Pigment Red 9, 19, 38, 43, 97, 122, 123, 144, 149, 166, 177, 179, 180, 192, 215, 216, 217, 220, 223, 224, and 226. 227, 228, 240, Pigment Blue 15, 15: 6, 16, 22, 29, 60, 64, Pigment Green 7, 36, Pigment Red 37, 138, 139, 147, 148, 153, 154, 166, 168, 185, Pigment Orange 36 and Pigment Violet 23 may be mentioned, but the invention is not limited to these. Furthermore, in order to obtain a desired hue, two or more kinds may be mixed and used.

The solvent used in the ink for forming the colored layer is preferably a solvent having an appropriate surface tension range of 40 mN / m or less and a boiling point of 130 ° C. or more. When the surface tension range is 40 mN / m or more, the dot shape stability during ink ejection is adversely affected, and when the boiling point is 130 ° C. or less, the drying property near the nozzle is increased. This is not preferable because it causes a defect such as nozzle clogging.

The resin used for the ink is casein, gelatin, polyvinyl alcohol, carboxymethyl acetal, polyimide resin, acrylic resin, epoxy resin, melamine resin, etc., and is appropriately selected according to the purpose.
Moreover, a dispersing agent is used in order to improve the dispersibility of the pigment | dye to resin, and specifically, various surfactants are used.

An example of the organic EL element will be described.
When the ink film is an organic light emitting medium layer that forms an organic EL element, the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, At least one is formed by ink ejection. The thickness of each of these layers is arbitrary, but is preferably in the range of 10 to 100 nm, and the total thickness of the organic light emitting medium layer is preferably in the range of 80 to 500 nm.

The hole injecting layer, the hole injecting material used for the hole transporting layer, and the hole transporting material are polyaniline, polythiophene, polyvinylcarbazole, a mixture of poly (3,4-ethylenedioxythiophene) and polystyrene sulfonic acid, Organic materials such as PPV derivatives and PAF derivatives are used. These hole transport materials include toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methanol, ethanol, isopropyl alcohol, ethyl acetate, butyl acetate, water, etc. It is used as a hole transport coating solution either alone or dissolved or dispersed in a mixed solvent.

The phosphor used for the organic light emitting layer 103c may be any phosphor generally used as an organic fluorescent material, and is a coumarin, perylene, pyran, anthrone, porphyrene, quinacridone, N, N′-dialkyl. Fluorochromes such as substituted quinacridone, naphthalimide, N, N'-diaryl-substituted pyrrolopyrrole, etc. dissolved in polymers such as polystyrene, polymethylmethacrylate, polyvinylcarbazole, PPV and PAF A polymeric fluorescent substance such as can be used.
The light-emitting layer made of these polymer materials comprises the above-described polymer materials, toluene, xylene, acetone, anisole, methylanisole, dimethylanisole, ethyl benzoate, methyl benzoate, mesitylene, tetralin, amylbenzene, methyl ethyl ketone, methyl isobutyl ketone. , Cyclohexanone, methanol, ethanol, isopropyl alcohol, ethyl acetate, butyl acetate, water and the like alone or mixed in a mixed solvent and used as an organic light emitting coating solution.

The hole blocking layer, the hole blocking material used for the electron transporting layer, and the electron transporting material are generally used as electron transporting materials, such as triazole, oxazole, oxadiazole, silole, and boron. Etc. dissolved in a polymer such as polystyrene, polymethyl methacrylate, polyvinyl carbazole, etc., alone in toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methanol, ethanol, isopropyl alcohol, ethyl acetate, butyl acetate, water, etc. Alternatively, it is dissolved or dispersed in a mixed solvent and used as an electron transport coating solution.

And as an electron injection material used for an electron injection layer, the material similar to the material used for the above-mentioned electron carrying layer can be used.

Explanatory drawing which shows the favorable state of the printed matter by ink discharge. Explanatory drawing which shows the color mixture state generate | occur | produced in the printed matter by ink discharge. Explanatory drawing which shows the state of the white blank generate | occur | produced in the printed matter by ink discharge. Cross-sectional explanatory drawing which shows an example of the printed matter of this invention. Sectional explanatory drawing of the partition concerning this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Support substrate 2 ... Partition wall 3 ... Bottom surface of partition wall 4 ... Upper surface of partition wall 5 ... Angle on partition side 6 ... Ink film 7 ... Concave portion of partition wall

Claims (6)

In an ink ejection printed matter having a support substrate, a partition wall that divides the support substrate into a large number of regions, and an ink film that is ejected and formed in the large number of regions using an ink ejection device,
An ink-discharge printed matter, wherein the partition has a cross-sectional shape in a normal direction of the support substrate. The ink ejection printed matter according to claim 1, wherein the partition wall has ink repellency. The ink ejection printed matter according to claim 2, wherein the partition wall has a smaller side ink repellency than an upper surface ink repellency. The ink discharge printed matter according to any one of claims 1 to 3, wherein the partition wall is a light shielding layer containing a black light shielding material. 5. The color filter according to claim 1, wherein the support substrate is a transparent substrate, the ink film is an ink-formed colored layer containing an organic light emitting material, and a color filter having a plurality of colored layers. The ink discharge printed matter according to any one of the above. The support substrate is a transparent substrate, the ink film is an organic light-emitting layer formed with an ink containing an organic light-emitting material, and is an organic electroluminescence device including a plurality of colors of organic light-emitting layers. Ink-discharge printed matter according to any one of 1 to 4.