TW201339728A - Color filter of color display device - Google Patents

Abstract

This invention provides a color display element simply and inexpensively obtained from a conventional monochrome electronic paper, without reducing brightness. Provided is a color filter used in a color display device having a monochrome display device and the color filter disposed at a recognition side of the display device, wherein the color filter has a transparent resin layer containing a transparent resin composition, the transparent resin composition being made of a resin solution having a transparent resin dissolved therein, a coloring area including plural colors coloring inks being formed on the transparent resin layer by an ink-jet method, the plural colors coloring inks containing at least a liquid resin at room temperature, a solid resin at room temperature, a coloring agent, and a solvent as an essential ingredient, the transparent resin layer absorbing only coloring ink solvent and liquid resin so as to form the coloring area, and outside the coloring area is no coloration or transparent.

Description

Color display device color filter

The present invention relates to a color filter, and more particularly to a color filter for a color display device such as a reflective color display.

E-paper, which is an electronic medium that replaces paper, is currently being developed. Compared with the CRT and liquid crystal display of the conventional display, the necessary characteristics of the electronic paper include, for example, a reflective display element having high white reflectance and high contrast, a memory effect on the display, and a low voltage driveable and thin. Light and cheap. In particular, as a display characteristic, white reflectance and contrast of the same quality as paper are required. In addition, traditional paper media can of course be displayed in full color, and the expectation of colorization of electronic paper is very large.

The technology for electronic paper that can be displayed in color has been proposed so far, for example, a medium in which a color filter is formed in a reflective liquid crystal device has been manufactured. However, these polarizers are generally used, so that light utilization efficiency is low and only dark white can be displayed. Furthermore, since the black color cannot be displayed, the contrast is also poor.

Further, as a bright reflective display device, there is a method of electrophoresis in which white particles and black particles charged by an electric field are used as a principle. However, the scattering reflectance of the white particles is weak and the maximum is 40%, and it is required to improve the reflection efficiency. Further, since the reflection efficiency is low when coloring is performed, I am looking forward to bright color electronic paper.

For example, Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4 disclose a reflective color display medium in which a color filter is formed by an electrophoretic display device. However, with respect to these display devices, it is possible to use a color filter having a black matrix used in a conventional liquid crystal display or to superimpose a colored pixel to impair luminance. Further, when the multi-color display element is realized in Patent Document 1, since the coloring pixels are formed only by photolithography of the same number of times as the color number of the coloring pixels, the cost of the step and the coloring photoresist are wasted.

On the other hand, a method of manufacturing a color filter using an inkjet method is a method in which a red, blue, and green ink is simultaneously spray-coated and hardened to form a pixel only for respective pixels required in a region constituting a pixel, and A method of forming a partition by a photolithography step and ejecting ink on the pixel portion (refer to Patent Document 5 and Patent Document 6). In this method, in order to avoid leakage of color regions and color mixing between adjacent regions, for example, Patent Document 7 exemplifies that the static contact angle of the ink and the partition wall surface is 30 to 65°, thereby avoiding color mixture. Compared with the aforementioned photolithography method, the method can reduce the cost of the step and the color resist.

Further, there has been proposed a method of forming a colored pixel without forming a partition in the production of a color filter of an ink jet method (refer to Patent Document 8). However, this method forms a black matrix layer on the substrate in advance and separates the color by the region. Further, the black matrix is not required in the electronic paper of the reflective display device, and the luminance is lowered.

In addition, the construction and manufacturing method of monochrome electronic paper is It is known that various transparent substrates are disposed on the viewing side of the capsules in black and white (see, for example, Non-Patent Document 1). Although the transparent support substrate on which the color filter is formed in advance may be attached to the panel, the colored region may be directly formed on the existing transparent support substrate, and it is important to configure the color filter on which transparent support substrate. And design its brightness. However, when a colored pixel is formed on a transparent supporting substrate by an inkjet method, since the surfaces of the transparent supporting substrates are different, the same coloring ink may have different wettability diffusion, and sometimes the wettability is too good. The coloring region cannot be controlled, and conversely, the wettability is poor, and the problem of uniform coloring regions having a desired area cannot be formed.

Further, in the manufacture of a uniform color filter in the plane, it is considered that the cleaning or surface treatment of the transparent support substrate makes the contact angle of the colored ink to the support substrate uniform. For example, it is washed by a conventional alkaline lotion, atmospheric plasma method, corona discharge, ultraviolet treatment, or the like. Since the ink deposited on the support substrate is in a liquid state, the contact angle is determined according to the wettability with the support substrate in addition to the surface tension, and the diffusion diameter is determined by the appropriate amount of liquid. However, such a surface treatment method is not suitable for mass production because it is necessary to set each transparent support substrate to the same contact angle setting condition, and the control range is limited. Further, when a colored region is directly formed by an inkjet method on a panel, such a surface treatment method may cause damage to the panel.

On the other hand, it is proposed that a pattern having a step and a partition wall are not provided in advance on the ink-jet pattern region on the transparent support substrate, and a base material of a silicone resin, an acrylic resin, or a polyvinyl alcohol is formed on the substrate. The ink receiving layer and means for forming a color filter layer thereon by an ink jet method (refer to Patent Documents 9 to 13). These are all suitable for liquid crystal displays (LCDs) In the case of a color filter, a receiving layer is usually formed on a transparent supporting substrate with a black matrix (BM), and the effect of the BM step is limited to prevent the scattering of the colored ink of the ink jet method and the occurrence of bleeding. Colored area (compartment). Further, the coloring components of any of the colored inks are absorbed by the receiving layer to be fixed, and are used for the purpose of forming a color filter, and in addition, in order to accelerate the absorption of the colored ink, there are cases in which fine particles such as cerium oxide are mixed (refer to the patent) Document 13).

Further, a method of forming a bonding layer on the surface of the capsule layer and forming a color filter by an inkjet method is proposed (refer to Patent Document 14). This bonding layer is used to loosely bond the release film for a protective surface, but there is no description about the shape of the ink that is ejected by the inkjet method.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. 2003-161964

[Patent Document 2] Japanese Laid-Open Patent Publication No. 2004-361514

[Patent Document 3] Japanese Laid-Open Patent Publication No. 2008-83536

[Patent Document 4] Japanese Laid-Open Patent Publication No. 2006-267831

[Patent Document 5] Japanese Laid-Open Patent Publication No. 59-75205

[Patent Document 6] Japanese Laid-Open Patent Publication No. 2001-350012

[Patent Document 7] Japanese Laid-Open Patent Publication No. Hei 11-281815

[Patent Document 8] Japanese Laid-Open Patent Publication No. 2010-54777

[Patent Document 9] Japanese Laid-Open Patent Publication No. 2000-28818

[Patent Document 10] Japanese Laid-Open Patent Publication No. 2006-209115

[Patent Document 11] Japanese Laid-Open Patent Publication No. 2003-84115

[Patent Document 12] Japanese Laid-Open Patent Publication No. 2004-226517

[Patent Document 13] Japanese Laid-Open Patent Publication No. 2010-276986

[Patent Document 14] Japanese Laid-Open Patent Publication No. 2010-503895

[Non-patent literature]

[Non-Patent Document 1] Yano Economic Research Institute, "The current status and future prospects of the 2010 edition of the electronic paper market"

The present invention has been made in view of the above-described state of the art, and provides a color filter which does not reduce the brightness and which can easily and inexpensively color the conventional monochrome electronic paper.

The inventors of the present invention conducted various reviews in order to solve the above problems, and as a result, it was found that the coloring area required to maintain the color filter is minimized and a colored region is formed by an inkjet method, whereby the amount of the colored ink can be suppressed. The necessary amount, the other becomes non-colored or transparent to suppress the decrease in brightness. In the color filter used in the conventional active liquid crystal display, it is necessary to provide a black matrix for the purpose of shielding the thin film transistor (TFT) provided in a pair of transparent substrates facing each other, for example, using micro In the case of the electrophoretic electronic paper of the capsule, since the pair of transparent substrates facing the entire surface are covered with black particles or white particles, the light cannot reach the opposite TFT from the viewing side, and thus the light shielding portion corresponding to the black matrix is not required. The case where the transparent substrate side is faced with a white particle or a mirror surface covering the TFT is also with. Furthermore, since the passive display and the segment display do not have TFTs, the light shielding portion is not required on the color filter side. In addition, the formation of colored regions by the ink jet method is advantageous in terms of cost.

Further, the colored region is stably produced in accordance with the surface property shape of the transparent supporting substrate provided on the viewing side of the monochrome display device such as a monochrome electronic paper using microcapsules, and is provided on the transparent supporting substrate. The transparent resin layer is effective, and the present invention has been completed on the basis of this finding.

That is, the present invention is a color filter for use in a color display device having a monochrome display device and a color filter disposed on a viewing side of the display device, wherein the color filter has a transparent color a transparent resin layer composed of a resin composition containing a resin solution in which a transparent resin is dissolved, and a colored region containing a plurality of colored inks formed by an inkjet method on the transparent resin layer, the complex color printing The ink contains at least a liquid resin at normal temperature, a resin which is solid at normal temperature, a coloring agent, and a solvent as essential components. The transparent resin layer absorbs only the solvent of the colored ink and the liquid resin to form a colored region, and the coloring region is outside the coloring region. Set to no color or transparency.

The color filter of the present invention can be suitably used as a color filter for a color display device having a monochrome display panel (monochrome display device), and the monochrome display panel is provided with a display body between a pair of transparent substrates having electrodes The display body includes particles that are moved or rotated by application of an electric field.

In the related color display device, first, the monochrome display device is preferably provided with charged white particles and black particles between a pair of transparent substrates having electrodes, and the particles form a display body by A person who applies an electric field to move or rotate to form a monochrome image. The display body may be, for example, a microcapsule in which electrophoretic particles are dispersed in a dispersion medium and sealed. The particle diameter of the microcapsules at this time is preferably from about 1 to 1000 μm, usually from several 10 μm. The black particles and the white particles in the microcapsules are charged, and these are sandwiched between transparent substrates having a pair of electrodes, and are displayed in a single color by applying an electric field. That is, as illustrated in Fig. 1, the monochrome display device includes a drive-side transparent substrate 3, and a drive electrode 2 that is connected to a drive switch 1 such as a thin film transistor (TFT) in a predetermined pattern; and a transparent side of the viewing side The substrate 5 has a conductive layer 4 such as ITO glass as an electrode, and the microcapsules 9 are disposed between the pair of substrates. In the microcapsule 9, the display body 10 including the white particles 6 and the black particles 7 which are mutually differently charged is dispersed in the transparent dispersion medium 8 and sealed.

Further, in the production of the color filter 11 disposed on the substrate on the viewing side of the monochrome display device, for example, the transparent resin layer 13 is first formed on the transparent support substrate 12 made of a transparent film or glass, and then On the transparent resin layer 13, only the colored region 14 of a necessary color number is formed by an inkjet method. Here, as the transparent film, a commercially available film such as a polycarbonate film, a PET film, a COP film or the like can be used. Further, by forming the transparent resin layer 13 on the transparent substrate 5 having the conductive layer 4 such as ITO glass, the transparent resin layer 13 can be directly formed on the transparent substrate on the side of the monochrome display device, and each coloring can be formed thereon. Area 14.

As the inkjet ink (colored ink) for forming the droplets of the colored region 14 of the present invention, at least a resin containing a liquid at normal temperature, a resin which is solid at normal temperature, a coloring agent, and a solvent are used as essential components. spray Ink ink. By such a composition, a good function of the transparent resin film to be described later can be found, and the colored region of the ink jet method can be precisely controlled, and the effects of the present invention can be found. Further, the term "normal temperature" as used in the present invention means an operating environment temperature at the time of inkjet ejection, which is a temperature range of about 25 ° C, for example, about 15 to 30 ° C.

The liquid resin at normal temperature used for the colored ink is a liquid polyfunctional acrylate, a liquid polyfunctional epoxy resin, or the like, and these may be used singly or in combination. Among these, a liquid having a molecular weight of 1,000 or less having a reactive group having a trifunctional group to a tetrafunctional group is preferably from the viewpoint of low reliability of ink resistance after photocuring and ink jet ejection characteristics. Resin.

Further, examples of the resin which is solid at room temperature used for the colored ink include a methacrylate copolymer, an unsaturated polyester resin, a saturated polyester resin, an urethane methacrylate resin, and the like. Can be used alone or in combination. Among these, from the viewpoint of transparency, a methacrylate copolymer or a saturated polyester resin is preferable, and in order to stably perform ejection of inkjet to achieve low viscosity, it is preferred that the average weight molecular weight is 10000 or less. In addition, in addition to saturated/unsaturated polyester resins used in dispersing pigments, polyethylene oxide alkyl ethers, polyethylene glycol diesters, sorbitan fatty acid esters, fatty acid modified A polymer surfactant such as a polyester or a tertiary amine-modified polyurethane such as a polyurethane is also a resin which is solid at normal temperature, and can be added together with a fine pigment.

The blending amount of the liquid resin at room temperature and the resin component of the solid resin at normal temperature is preferably in the range of 1 to 50% by weight for the colored ink. Further, it is preferably a liquid resin at normal temperature and at room temperature The blending ratio of the solid resin is in the range of 10:90 to 99:1.

As the solvent used for the colored ink, for example, ethylene glycol monoalkyl ether acetate such as ethylene glycol monomethyl ether acetate; diethyl ether such as diethylene glycol monomethyl ether or diethylene glycol monoethyl ether; Glycol monoalkyl ethers; diethylene glycol monoalkyl ether acetates such as diethylene glycol mono-n-butyl ether acetate; propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, etc. Esters; other ethers such as diethylene glycol dimethyl ether; high-boiling solvents such as γ-butyrolactone.

Further, the colored ink is mainly red (R), green (G), and blue (B), and can be blended with a predetermined coloring agent in accordance with the desired color. However, in a color filter used in a reflective display device such as an electronic paper, there is also a case where a colored region which is colorless or transparent or does not need to be adjusted in color is used. In this case, it is of course possible to form a colored coating film without blending a coloring agent to become non-colored or Transparent.

In the case of blending a coloring agent, it can be arbitrarily selected from an organic coloring agent and an inorganic coloring agent. As the organic colorant, for example, a dye, an organic pigment, a natural pigment, or the like can be used. Further, as the inorganic colorant, for example, an inorganic pigment, an extender pigment or the like can be used. Among these, organic pigments are preferably used because of high color developability and high heat resistance. An organic pigment such as a color index (C.I.: Dye and Color Society) is classified as a pigment (Pigment) compound, specifically, for example, the following color index (C.I.) number.

That is, CI Pigment Yellow-1, CI Pigment Yellow-3, CI Pigment Yellow-12, CI Pigment Yellow-13, CI Pigment Yellow-14, CI Pigment Yellow-15, CI Pigment Yellow-16, CI Pigment Yellow-17 , CI Pigment Yellow-20, CI Pigment Yellow-24, CI Pigment Yellow-31, CI Pigment Yellow-55, CI Pigment Yellow-60, CI Pigment Yellow-61, CI Pigment Yellow-65, CI Pigment Yellow-71, CI Pigment Yellow-73, CI Pigment Yellow-74, CI Pigment Huang-81, CI Pigment Yellow-83, CI Pigment Yellow-93, CI Pigment Yellow-95, CI Pigment Yellow-97, CI Pigment Yellow-98, CI Pigment Yellow-100, CI Pigment Yellow-101, CI Pigment Yellow- 104, CI Pigment Yellow-106, CI Pigment Yellow-108, CI Pigment Yellow-109, CI Pigment Yellow-110, CI Pigment Yellow-113, CI Pigment Yellow-114, CI Pigment Yellow-116, CI Pigment Yellow-117, CI Pigment Yellow-119, CI Pigment Yellow-120, CI Pigment Yellow-126, CI Pigment Yellow-127, CI Pigment Yellow-128, CI Pigment Yellow-129, CI Pigment Yellow-138, CI Pigment Yellow-139, CI Pigment Yellow-150, CI Pigment Yellow-151, CI Pigment Yellow-152, CI Pigment Yellow-153, CI Pigment Yellow-154, CI Pigment Yellow-155, CI Pigment Yellow-156, CI Pigment Yellow-166, CI Pigment Yellow- 168, CI Pigment Yellow-175; CI Pigment Orange 1, CI Pigment Orange 5, CI Pigment Orange 13, CI Pigment Orange 14, CI Pigment Orange 16, CI Pigment Orange 17, CI Pigment Orange 24, CI Pigment Orange 34, CI Pigment 36, CI pigment orange 38, CI pigment orange 40, CI pigment orange 43, CI pigment orange 46, CI pigment orange 49, CI pigment orange 51, CI pigment orange 61, CI pigment orange 63, CI pigment orange 64, CI pigment orange 71, CI pigment orange 73, CI pigment purple 1, CI pigment purple 19, CI pigment purple 23, CI pigment purple 29, CI pigment purple 32, CI pigment purple 36, CI pigment purple 38; CI pigment red 1, CI pigment red 2. CI Pigment Red 3, CI Pigment Red 4, CI Pigment Red 5, CI Pigment Red 6, CI Pigment Red 7, CI Pigment Red 8, CI Pigment Red 9, CI Pigment Red 10, CI Pigment Red 11, CI Pigment Red 12, CI Pigment Red 14, CI Pigment Red 15, CI Pigment Red 16, CI Pigment Red 17, CI Pigment Red 18, CI Pigment Red 19, CI Pigment Red 21, CI Pigment Red 22, CI Pigment Red 23, CI Pigment Red 30, CI Pigment Red 31, CI Pigment Red 32, CI Pigment Red 37, CI Pigment Red 38, CI Pigment Red 40, CI Pigment Red 41, CI Pigment Red 42, CI Pigment Red 48:1, CI Pigment Red 48:2, CI Pigment Red 48:3, CI Pigment Red 48:4, CI Pigment Red 49:1, CI Pigment Red 49:2, CI Pigment Red 50:1, CI Pigment Red 52:1, CI Pigment Red 53 1, CI Pigment Red 57, CI Pigment Red 57:1, CI Pigment Red 57:2, CI Pigment Red 58:2, CI Pigment Red 58:4, CI Pigment Red 60:1, CI Pigment Red 63:1 CI Pigment Red 63:2, CI Pigment Red 64:1, CI Pigment Red 81:1, CI Pigment Red 83, CI Pigment Red 88, CI Pigment Red 90:1, CI Pigment Red 97, CI Pigment Red 101, CI Pigment Red 102, CI Pigment Red 104, CI Pigment Red 105, CI Pigment Red 106, CI Pigment Red 108, CI Pigment Red 112, CI Pigment Red 113, CI Pigment Red 114, CI Pigment Red 12 2. CI Pigment Red 123, CI Pigment Red 144, CI Pigment Red 146, CI Pigment Red 149, CI Pigment Red 150, CI Pigment Red 151, CI Pigment Red 166, CI Pigment Red 168, CI Pigment Red 170, CI Pigment Red 171, CI Pigment Red 172, CI Pigment Red 174, CI Pigment Red 175, CI Pigment Red 176, CI Pigment Red 177, CI Pigment Red 178, CI Pigment Red 179, CI Pigment Red 180, CI Pigment Red 185, CI Pigment Red 187, CI Pigment Red 188, CI Pigment Red 190, CI Pigment Red 193, CI Pigment Red 194, CI Pigment Red 202, CI Pigment Red 206, CI Pigment Red 207, CI Pigment Red 208, CI Pigment Red 209, CI Pigment Red 215, CI Pigment Red 216, CI Pigment Red 220, CI Pigment Red 224, CI Pigment Red 226, CI Pigment Red 242, CI Pigment Red 243, CI Pigment Red 245, CI Pigment Red 254, CI Pigment Red 255, CI Pigment Red 264, CI Pigment Red 265; CI Pigment Blue-15, CI Pigment Blue-15:3, CI Pigment Blue-15:4, CI Pigment Blue-15:6, CI Pigment Blue-60; CI Pigment Green 7, CI Pigment Green 36; CI Pigment Brown 23 , CI Pigment Brown 25; CI Pigment Black 1, CI Pigment Black 7, and the like.

Further, specific examples of the inorganic pigment and the extender pigment include titanium oxide, barium sulfate, calcium carbonate, zinc oxide, lead sulfate, yellow lead, zinc yellow, red dan (red iron oxide (III)), cadmium red, ultramarine blue, Prussian blue, chrome oxide green, cobalt green, amber, titanium black, synthetic iron black, carbon black, and the like. Further, the coloring agents blended in each of the colored inks may be used alone or in combination of two or more.

In consideration of nozzle clogging or the like when the colored ink is ejected by the inkjet method, the colorant is preferably micronized/dispersed with the polymer dispersant to have a particle size of 100 nm or less. That is, in order to disperse the colorant well, a dispersing agent may be blended in the colored ink as needed. For example, a surfactant such as a cationic system, an anionic system, a nonionic system, an amphoteric, an anthracene resin or a fluorine-based surfactant can be used. Among the surfactants, a polymer surfactant (polymer dispersant) exemplified below is preferred. That is, polyethylene oxide alkyl ether such as polyethylene oxide lauryl ether, polyethylene oxide stearyl ether, polyethylene oxide oleyl ether; polyethylene oxide octyl phenyl ether Polyethylene oxide alkyl phenyl ethers such as polyethylene oxide nonylphenyl ether; polyethylene glycol diesters such as polyethylene glycol dilaurate and polyethylene glycol distearate Sorbitol fatty acid ester A polymer surfactant such as a fatty acid-modified polyester or a tertiary amine-modified polyurethane.

The content of the colored ink in the case where the colorant is blended is usually blended in a ratio of from 1 to 60% by weight, preferably from 5 to 40% by weight, to the solid colorant in the ink. When the blending ratio of the solid colorant in the ink is less than 1% by weight, the penetration density of the colored ink having a predetermined film thickness (generally about 0.1 to 2.0 μm) is insufficient. On the other hand, when it is more than 60% by weight, when the colored ink is ejected from the transparent resin layer and cured, the adhesion of the colored coating film to the transparent resin layer is deteriorated, and the properties of the coating film such as the hardness of the coating film are insufficient. Hey. Further, the solid portion of the present invention is calculated from the weight of the colored ink after heating at 160 ° C for 2 hours, and is a total amount of the solvent and the other components of the volatile component when the solvent is substantially contained.

The ink property of the droplets which are stably formed in the ink jet head of a general piezoelectric element varies depending on the characteristics of the head, but the viscosity at the temperature inside the head is 3 to 150 mPa. Sec, preferably 4 to 30 mPa. Sec. When it is larger than it is, it cannot be ejected. When it is lower than it is, the discharge amount is not stable. The surface tension may be 20 to 40 mN/m at the temperature inside the shower head. When it is larger than this, the droplets cannot be ejected at the start of coating, and when it is lower, the amount of droplets when continuously ejected is unstable. The temperature inside the nozzle is based on the stability of the material, but it is used at room temperature of 20 to 45 °C. In order to increase the solid content in the ink and increase the film thickness, it is preferably used at a temperature of about 35 to 45 °C.

The coloring region is, for example, a monochrome display device as shown in Fig. 1, and at least blue, green, and red are applied to the driving side transparent substrate 3 so as to have a plurality of colors in a region in which the driving electrodes 2 are formed. 3 colors. That is, one pixel of the color filter is formed corresponding to one pixel of the monochrome display device. Further, in order to expand the color reproducibility region and increase the brightness, yellow, cyan, transparent regions, and the like may be formed. In the manufacture of such a multicolor color filter, it is advantageous to omit the development step by the inkjet method (inkjet method) as compared with the photolithography method.

Further, in the present invention, when the colored region is formed by the ink jet method, a preferred aspect corresponds to the area of the colored region 14 in the color filter 1 pixel of the pixel of the monochrome display device 1 to be compared with the area of 1 pixel. The ratio is formed by 90% or less. That is, as shown in Fig. 2, when the lattice unit formed by the wiring 15 connected to the drive electrode 2 of the drive switch (TFT) 1 is defined as a 1-pixel unit, the colored region 14 on the color filter side is It is formed correspondingly thereto, and its area is preferably 90% or less for 1 pixel unit. When the colored region is formed by the inkjet method, in particular, when the three colors are simultaneously formed, the area ratio is necessary in order to avoid color mixing, and further, when the incident light from the outside passes through the colored region and is reflected by the white particles in the microcapsule, The aforementioned area ratio is also necessary in order not to be incident on adjacent distinct colored regions.

On the other hand, in the passive or segmented mode, in the common region sandwiched between the patterned electrode and the conductive layer, since the charged particles move more to become the pixel opening portion, the colored region 14 on the color filter side is still relatively Good for the above area ratio of 90% or less. Further, in the color filter, the portion other than the colored region is free from coloring or transparency, thereby reducing the amount of use of the colored ink while realizing a bright color display element. Further, the lower limit of the area of the colored region is 50% or more, and when it is lower than this, the scattered light from the white particles becomes difficult. Present a substantial color.

Furthermore, the drop tolerance of droplets printed by ink jet printing is generally 5 to 7 μm. Therefore, the coloring area is 90% or less, whereby color mixing between pixels in simultaneous printing of three colors can be avoided, contributing to improvement in productivity. Further, the landing tolerance, for example, when printing a pixel area of 120 μm square, gives a tolerance of about 10% in the area ratio of the colored area. In the present invention, when the same amount of pigment is present in the pixel, if the colored region is 50% or more, the color characteristics are less affected within the coloring area tolerance.

Regarding the colored ink for forming the colored region, in addition to the above components, a resin which is hardened by ultraviolet rays or heat may be added together with the polymerization initiator as needed. Such a resin which is cured by ultraviolet rays or heat is preferably a liquid resin having ultraviolet curability, in view of compatibility with other components and suitability for continuous ejection of inkjet. Preferably, the viscosity is 12000 mPa at 25 ° C. s the following range. Viscosity is 12000 mPa. When s is big, the shape of the falling droplets may become uneven.

Among them, a polyfunctional monomer can be used as the ultraviolet curable component of the colored ink, and a liquid polyfunctional acrylic monomer is preferable. More preferably, it is a low-viscosity bifunctional to trifunctional polyfunctional acrylic monomer which is easily ejected by ink jet. Examples of the functional group include an acryloxy group, a methacryloxy group, and the like, and of course, these may be used. Specific examples of the ultraviolet curable component include, for example, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, 1,4-butanediol diacrylate, and ethylene glycol dimethacrylate. , neopentyl glycol diacrylate, trimethylolpropane triacrylate, 1,3-butylene glycol dimethacrylate, and the like. In addition, in addition to these, A tetrafunctional or higher polyfunctional acrylic monomer or oligomer can be added to the high photocurability. For example, a trifunctional or 4-functional acrylate or methacrylate having neopentyl alcohol as a skeleton, a 5-functional or 6-functional acrylate or methacrylate having a neopentyltetraol skeleton as a skeleton . Further, when the liquid polyfunctional acrylic monomer is selected from the ultraviolet curable component, it can also serve as a liquid resin at room temperature in the present invention.

Further, as the thermosetting component which is hardened by heat, in addition to the above-mentioned polyfunctional acrylic monomer, it may be converted into a thermosetting component, and a phenol novolak type epoxy resin or a cresol novolac resin may be mentioned. Epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, biphenyl epoxy resin, alicyclic epoxy resin, epoxy resin, phenyl shrinkage An epoxy resin such as glyceryl ether, p-butylphenol glycidyl ether, triglycidyl isocyanate, diglycidyl isocyanate, allyl glycidyl ether or glycidyl methacrylate.

Further, in the colored ink, a binder is added in the viscosity range in which the inkjet can be ejected for the purpose of film formation. As the binder, either a resin having no polymerization property or a resin having polymerization reactivity itself may be used, or two or more kinds of binders may be used in combination. When the binder is a solid at normal temperature, it can also serve as a resin which is solid at room temperature in the present invention.

Further, a photopolymerizable ink can be blended with the photopolymerization initiator. The photopolymerization initiator is appropriately selected in consideration of the type of each material in addition to the reaction form of the binder or the polyfunctional monomer (for example, radical polymerization, cationic polymerization, etc.), but 1-hydroxycyclohexyl group is exemplified. -Phenyl ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-methyl-1-[4-(methylthio)benzene 2-ylmorpholinylpropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butan-1-one, 2-hydroxy- 2-methyl-1-phenyl-propan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2,4,6-trimethylbenzimidyldiphenyl-phosphine oxide, bis-indenylphosphine oxide, benzoin ethyl ether, benzoin isobutyl ether, benzoin isopropyl ether, 2-isopropylthioxanthone (2- Isopropylthioxanthone), 2,4-diethylthioxanthone, 2-(3-dimethylamino-2-hydroxypropoxy)-3,4-dimethyl-9H-thioxanthone-9-one Inter-chloride, diphenyl ketone, methyl o-benzhydryl benzoate, 4-benzylidene-4'-methyl-diphenyl sulfide, 3,3', 4,4'-four (t-butylperoxycarbonyl), p-dimethylamino benzoic acid ethyl ester, p-dimethylamino benzoic acid isoamyl ester, 1,3,5-tripropenyl hexahydro-s-three S-triazine, 2-[2-(5-methylfuran-2-yl)vinyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-( Furan-2-yl)vinyl]-4,6-bis(trichloromethyl)-s-triazine, methyl benzomethionate, 2,4,6-trimethylbenzhydryldiphenyl Phosphine oxide Polymerization initiator.

According to the present invention, in the colored region of one pixel corresponding to the one-pixel color filter formed by the monochrome display device, the colored ink ejected by the inkjet method is fixedly spread at any position on the transparent resin film, and is repeatedly applied thereto. In the subsequent drying and exposure, a transparent resin layer having an absorbability to a solvent or a liquid polyfunctional acrylic monomer is formed so as not to greatly change the area and shape of the colored region. The transparent resin layer may have a thickness of from 1 μm to 30 μm, preferably from 3 to 20 μm. Further, it is preferable that the transparent resin layer has a light transmittance of 95% or more at a film thickness of 400 nm.

The colored ink sprayed by the inkjet method, first in the transparent resin The film spreads fixedly and settles at a static contact angle. Then, before the ink that is subsequently ejected is overlapped or before the drying step, the solvent of the volatile component in the colored ink component and the liquid resin at normal temperature are absorbed by the transparent resin layer in a short time, and the pigment in the colored ink is colored. The agent and the solid resin at normal temperature are fixed to the contact surface with the surface of the transparent resin layer, and the area of the colored region does not change even in the subsequent drying step. Therefore, even if, for example, red, blue, and green colored inks are simultaneously printed by the respective ink jet heads in respective predetermined areas, when printing without mutual color mixing, from the viewpoint of controlling the wettability diffusion path of the colored ink, The static contact angle of the colored ink and the transparent resin layer is preferably from 4 to 40. When it is less than 4°, the ink may spread to a desired area or more, and it is difficult to form a film thickness required to achieve a desired color density. Further, when the static contact angle exceeds 40°, when a plurality of dots are drawn in a pixel, a white dot or a non-colored region between dots is adversely affected.

A transparent resin composition mainly composed of a resin component constituting the transparent resin layer, which is a transparent substrate on the viewing side of the monochrome display device or a transparent resin layer formed on another transparent support substrate on which the color filter is formed. Apply to any of these and dry. A conventional coating method can be used for the coating method, but it is selected according to various characteristics such as a coating amount to impart a film thickness of a desired transparent resin layer, a coating speed, or a viscosity of a transparent resin composition. For example, a method of applying a transparent resin composition containing a liquid resin solution in which a transparent resin is dissolved, and drying it, using a die coater, a slit coater, a gravure coater, a ripper coater, or the like, may be applied. Alternatively, a transparent film-like transparent resin layer is formed on any of the support films in advance, and the transparent substrate on the side of the monochrome display device or the other color filter is formed. A means for forming a method of thermal lamination transfer on a transparent support substrate.

As described above, the film thickness of the transparent resin layer is preferably from 1 to 30 μm, more preferably from 3 to 20 μm. When the thickness is less than 1 μm, the control of the diffusion of the target color ink is insufficient, and when it exceeds 30 μm, color mixture of reflected light from the microcapsules may occur between the colored pixels.

In addition, the light transmittance of the transparent resin layer at 400 nm has an important influence on the brightness of the panel, and the higher the better, the more than 95% can be used. Therefore, the transparent resin composition forming the transparent resin layer is mainly composed of a transparent resin component, and a component which maintains the transmittance in the manufacturing environment and the use environment of the panel is further selected.

The transparent resin composition having the transparent resin layer having the above various characteristics has film forming property at room temperature, and preferably contains a resin binder which does not have viscosity. A resin composition mainly composed of a transparent resin binder can be exemplified as suitable for imparting such characteristics. The glass transition temperature or melting point of the transparent resin binder is preferably 23 ° C or higher at room temperature, so that a methacrylate copolymer, an aliphatic polyester copolymer, a polyvinyl alcohol/polyvinyl ether/polyvinyl ester copolymer can be exemplified. , unsaturated polyester, etc. These are selected such that the solvent constituting the colored ink is compatible with the liquid resin (for example, a polyfunctional monomer component) at a normal temperature. When the compatibility is poor, when the colored ink on the transparent resin layer is dried, optical defects such as mist or scattering may occur.

Further, as the solvent for the colored ink, it is preferred to use propylene glycol, lactic acid, ethylene glycol, diethylene glycol, dipropylene glycol monoacetate, diacetate or monoethylacetate monoester as described above. Therefore, the inclusion Such a solvent-colored ink can be used as a suitable binder resin combination of a transparent resin composition, and a compound having an ester group in a molecule such as a methacrylic acid copolymer, an aliphatic polyester copolymer or an unsaturated polyester can be used. The binder resin has a weight average molecular weight of from 2,000 to 100,000, preferably from about 2,000 to 30,000. When the molecular weight exceeds 100,000, the compatibility with the colored ink may be poor. Further, when the binder resin is a resin having an acid value derived from a carboxyl group in a molecule, it absorbs a solvent of a colored ink and fixes a contact line, which is suitable. In this case, an appropriate acid value may range from 10 to 120 mgKOH/g.

Further, it can be suitably used for a viscous resin having a photo-crosslinking property of an acrylate or methacrylate having a glycidyl residue in a part of the carboxyl group.

Further, a polyfunctional acrylic monomer having a UV curability and a photoinitiator may be blended on the transparent resin composition. When a liquid polyfunctional acrylic monomer is blended, it is suitable because the softening point of the transparent resin layer is lowered to absorb the solvent of the colored ink and to control the diffusion of the colored ink. The acrylic monomer and the photoinitiator selected herein may be the same as those exemplified above for the colored ink, and it is preferred to use a colorless one. The component is preferably the same as the component in the colored ink, but the type and the number of blending components in the coloring component are not limited to the examples of the present invention.

In the case where the transparent resin composition is used in combination with the resin binder and the above polyfunctional acrylic monomer, the blending ratio is a resin binder/acrylic monomer = 35 to 95 parts by weight/5 to 65 parts by weight, preferably 40 to 90 parts by weight/10 to 60 parts by weight. The ratio of resin binder is less than 35 In the case of parts by weight, the transparent resin layer is viscous, and after the colored ink is formed and dried, the shape of the colored region on the transparent resin layer becomes concave, which is not preferable. When the photoinitiator is blended, the total amount of the resin binder and the polyfunctional acrylic monomer may be 15 parts by weight or less, preferably 10 parts by weight or less. When the amount is more than 15 parts by weight, the light transmittance of 400 nm becomes less than 95% and the white balance is lowered, which is not preferable.

By imparting photocurability to the transparent resin layer and forming a colored region by an inkjet method, the transparent resin layer is cured by irradiating ultraviolet rays together with the colored region, whereby the adhesion to the substrate can be improved, and the film strength and reliability can be maintained.

Further, the transparent resin layer can be used in the rework process of the color filter by the presence or absence of the ultraviolet curable underlayer strength and the increase in the chemical resistance. That is, after the colored region is formed on the transparent resin layer by the inkjet process, when the colored region is insufficient, the adhesive film can be used before the ultraviolet curing, and the transparent resin layer and the colored region can be removed together with the cleaning solvent.

Further, in order to promote the absorption of the colored ink, the transparent resin composition of the transparent resin layer is formed, and the conventional colorless fine particles of 10 to 200 nm can be mixed in a range in which the transparency is not impaired. For example, cerium oxide microparticles, acrylic microparticles, polyvinylpyrrolidone microparticles, alumina, and the like.

The constituent components forming the transparent resin layer are dissolved in a solvent, and a surfactant is added as needed for the purpose of imparting better coating properties. The liquid transparent resin composition can be applied by a die coater or a slit coater. A cloth machine, a gravure coater, a knurling wheel coater, or the like is applied to a transparent display substrate of a monochrome display device or a transparent support substrate on which a color filter is formed. Then, it is dried, for example, at 40 ° C to 110 ° C, whereby a desired transparent resin layer can be obtained. Appropriate addition amount of surfactant, for transparent resin The composition may be from 0.005 to 0.5 parts by weight, more preferably from 0.005 to 0.1 parts by weight, per 100 parts by weight of the surfactant. When the surfactant is not present, the surface becomes orange peel when the transparent resin composition is dried, and the unevenness becomes remarkable, and the optical characteristics are lowered, and the diffusion shape of the ink droplets thereafter becomes unsatisfactory, which is not preferable. Further, when the amount of the surfactant exceeds 0.5 parts by weight, the ink diffusion diameter of the colored ink is increased when the colored ink is dropped, and the range of the pixel region (colored region) for the purpose is exceeded. As such a surfactant, a nonionic surfactant is preferably used, and a lanthanide-based or fluorine-based surfactant is more preferably used. Specifically, a BYK series manufactured by BYK Corporation, a FC series manufactured by DIC, or the like can be exemplified.

When the colored ink is ejected from the inkjet nozzle by an inkjet method to form a colored region, it may be formed by one drop of the colored ink, or a colored region may be formed by a plurality of drops. In this case, when the coloring area S of one pixel of the color filter of the one-pixel corresponding to the monochrome display device is formed by the inkjet method, it is preferable to visually inject the colored ink from the inkjet nozzle 1 onto the transparent resin layer. The contact area a ₀ formed at the time. That is, in the case where S is larger than a ₀ , a plurality of droplets can be drawn in the 1 colored region, and the droplets can be overlapped, independently, and combined. Further, in the case where the plurality of droplets are drawn in one pixel, the appearance of the droplets differs depending on the difference in the landing time between the droplets, but the inkjet drawing method is not limited to the method described herein. Further, when the droplets which are deposited on the transparent resin layer of the present invention are dried and observed in shape, the diffusion diameter before and after drying hardly changes, and it is preferable to have a convex shape. At this time, depending on the surface property shape of the transparent supporting substrate, the coloring area and the shape-stabilized color filter can be formed by the inkjet method.

Further, in the color display device to which the color filter of the present invention is applied, the colored pattern formed by the colored region of the color filter is not particularly limited, and an appropriately suitable shape can be used. For example, when the shape of each graphic is a rectangle, a square, or a nearly circular shape, the three types of patterns may be repeatedly arranged, may be arranged in an L shape, and may be arranged in a triangle shape. Furthermore, it may be arranged in a mosaic or irregularly arranged. Further, a transparent pattern may be included together with the colored graphics formed by the plurality of colored regions. The ink jet method has a feature that a variety of patterns can be selected without using a photomask as compared with a method of manufacturing a color filter using a colored photoresist. Furthermore, it is not necessary to repeat a plurality of photolithography steps in a multicolor representation of four or more colors, which is advantageous in terms of cost. In addition, "no coloring" in this specification means that a coloring pattern is not formed on a color filter. In addition, the term "transparent" other than the colored region means that a transparent ink (transparent region) is formed using a color ink that does not contain a coloring agent such as a pigment.

When the colored ink has ultraviolet curability, an effective means for obtaining a uniform color filter may be a method in which at least ultraviolet exposure is performed after inkjet coating and drying, and the subsequent heat treatment step does not diffuse the pattern region. In the case of such a method, it is not necessary to completely cure the colored ink by ultraviolet exposure, and it is possible to carry out the ultraviolet irradiation amount to the extent that the pattern area is not diffused in the subsequent treatment.

Further, the principle of operation of the color display device to which the color filter of the present invention is suitable is, for example, the following. In other words, between the pair of transparent substrates provided with the color filter on at least one side, microcapsules in which white electrophoretic particles and black electrophoretic particles are dispersed in a transparent dispersion medium, or rotating particles having white and black surface regions are disposed. In a color display device, for When the electrophoretic particle or the rotating particle applies a positive electric field on the color filter side, the white electrophoretic particle or the white region of the rotating particle is negatively charged to move to the color filter side or change direction by rotation, and reflect from the observation side ( The light of the viewing side penetrates the opposite colored graphic and becomes the color display of its colored graphic. Conversely, when an electrophoretic particle or a rotating particle applies an electric field in a negative direction on the color filter side, the black region of the black electrophoretic particle or the rotating particle moves to the color filter side or changes direction by rotation, and absorbs light from the observation side. And won't be a color display. The direction of the electric field applied to the electrophoretic particles or the rotating particles is appropriately selected/controlled in such a manner that a predetermined color display can be performed.

Bright color electronic paper can be realized by the color filter of the present invention constructed as above. Further, when the color filter is manufactured, the number of steps and the amount of material used can be reduced, and a stable colored region can be formed without mixing colors.

Further, an organic film is used as a transparent support substrate for forming a color filter, and a transparent resin layer is directly formed on one side of a substrate of a monochrome display device without using a transparent support substrate to form a predetermined colored region, thereby Light weight and thinness contribute. Further, a means for simply coloring the color filter film on a conventional monochrome type electronic paper can be expected.

1‧‧‧Drive Switch

2‧‧‧Drive electrode

3‧‧‧Drive side substrate

4‧‧‧ Conductive layer

5‧‧‧Transparent substrate

6‧‧‧White particles

7‧‧‧Black particles

8‧‧‧Distributed media

9‧‧‧microcapsules

10‧‧‧Display media

11‧‧‧ color filter

12‧‧‧Support substrate with transparent resin layer

13‧‧‧Transparent resin layer

14‧‧‧Colored layer

15‧‧‧ wiring

Fig. 1 is a schematic cross-sectional view (partial view) showing an example of a color display device of the present invention.

Fig. 2 is a plan view schematically showing a state in which a transparent substrate having a driving side of a TFT is formed on one of a pair of transparent display devices.

Fig. 3 (a) and (b) are explanatory diagrams showing the drawing pattern of the colored ink.

Figure 4 is a schematic illustration showing other depictions of the colored ink.

Fig. 5 (a) and (b) are explanatory views showing the appearance of the colored region of the colored ink.

Fig. 6 is a schematic explanatory view showing the drawing order of the 8-dot drawing of the colored ink.

Fig. 7 (a) and (b) show surface shape measurement data for describing the surface shape of the pattern.

The invention will be specifically described below by showing examples of embodiments of the invention. Furthermore, the invention is not limited to the embodiments. In addition, the "parts" are expressed by weight unless otherwise specified.

[Examples] [Modulation of Colored Inkjet Ink (R1: Red, G1: Green, B1: Blue)]

As shown in Table 1, first, a color filter is used for fine pigments, and in the presence of a polymer dispersant, diethylene glycol monoethyl ether acetate is used as a solvent and dispersed in a bead mill to prepare red, green, and Blue dispersion. The dispersion was mixed in the composition shown in Table 1, and the mixed solution was subjected to pressure filtration by a 1 μm microfilter to prepare colored inkjet inks (colored inks) of respective colors. The physical property values are combined and shown in Table 1.

In addition, the meanings of the abbreviation of Table 1 and Table 2 mentioned later are as follows.

"PE-4A": Pentaerythritol tetraacrylate (manufactured by Kyoeisha Chemical Co., Ltd.)

"EGDAC": Diethylene glycol monoethyl ether acetate (Daicel Chemical Industry Co., Ltd.)

"KBM-5103": 3-propenyloxypropyltrimethoxydecane (manufactured by Shin-Etsu Chemical Co., Ltd.)

"Irgcure 907": 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinylpropan-1-one (manufactured by Ciba Japan)

"BYK-378": polyether modified polydimethyl siloxane based surfactant (BYK company)

"PR254": Pigment Red 254

"PG36/PY150=50/50": Co-dispersion of Pigment Green 36 and Pigment Yellow 150

"PB15:6": Pigment Blue 15:6

"P1": the resin obtained in Synthesis Example 1

"P2": resin obtained in Synthesis Example 2

"P3": resin obtained in Synthesis Example 3

"P4": saturated polyester resin TP217 (manufactured by Nippon Synthetic Chemical Co., Ltd., molecular weight 16000, glass transition point 40 ° C, 40% concentration)

"Q1": Pentaerythritol tetraacrylate (PE-4A, Kyoeisha Chemical Co., Ltd.)

"Q2": Trimethylolpropane triacrylate (TMPA)

Further, among the physical property values shown in Table 1, the ink viscosity was measured at 23 ° C using an E-type viscometer. The surface tension of the ink was measured by using a buoyancy method of a platinum plate using CBVP-Z (manufactured by Kyowa Interface Science Co., Ltd.) at 23 °C. In addition, regarding the surface shape and size of the colored pixel (colored region) described below, the shape after lapse and hardening was measured by an optical microscope, and an optical interference type surface shape measuring device WYCO NT 1100 (Veeco, Japan) was used. Company system) Determination of shape. Further, an inkjet head (KM512M, 14 pl gauge) manufactured by Konica Minolta was used, and each of the obtained colored inks R1 obtained above was carried out at a head temperature of 23 ° C at a driving frequency of 4.8 kHz and an applied voltage of 16.8 V. The 10 minute continuous discharge test of B1 and G1 was completely blocked by the nozzle, and it was confirmed that the discharge characteristics were good.

[Preparation of Transparent Resin Composition Forming Transparent Resin Layer]

The properties of the resin solution obtained in the following synthesis examples were determined in the following manner.

<solid concentration>

1 g of the obtained resin solution (including the reaction product and the (meth) acrylate resin containing a polymerizable double bond) was immersed in a glass filter [weight: W0 (g)], and weighed [weight: W1 (g) ], the weight [W2 (g)] after heating at 160 ° C for 2 hours, and the solid content concentration was determined by the following formula.

Solid concentration (% by weight) = 100 × (W2-W0) / (W1-W0)

Acid price

Put the resin solution in two The dioxane was dissolved, and it was determined by titration with a 1/10 N-KOH aqueous solution using a potentiometric titration apparatus (manufactured by Hiroshima Seisakusho Co., Ltd., trade name: COM-1600).

<Molecular weight>

The weight average molecular weight (Mw) was determined by a gel permeation chromatography (GPC) using tetrahydrofuran as a developing solvent in terms of a standard polystyrene.

<glass transition point>

The resin solution was spin-coated on a glass substrate, and dried at 100 ° C for 1 hour to obtain a coating film, and the resulting coating film was used to determine a glass transition point by a DSC method.

<stickiness>

By touching the surface of the dried transparent resin film, no stickiness or no fingerprint remains, and it is defined as "no stickiness ○".

<Transparency>

With a transparent support substrate as a reference, a transparent resin-attached support substrate with a transparent resin layer is applied to Hitachi Hitech The Fielding U-4000 measures light from 350 nm to 700 nm.

(Synthesis Example 1)

Add isobutyl methacrylate (iBMA) 54.5 g (0.384 mol) and methyl methacrylate (MMA) 76.8 g (0.768 mol) to a 1000 ml four-necked flask equipped with a nitrogen inlet and a reflux tube. 2,2'-azobis(2-methylbutyronitrile) (AIBN) 1.0 g (0.006 mol) and PGMEA (propylene glycol monomethyl ether acetate) 200 g, stirred under a nitrogen atmosphere of 80 to 85 ° C It was polymerized in 8 hours. After cooling to room temperature, PGMEA was added to adjust the solid content to 30% to obtain a resin solution 1. The resin P1 contained in the obtained resin solution 1 had Mw = 65,000 and an acid value of 1 or less and could not be measured. The glass transition point is 45-50 °C.

(Synthesis Example 2)

Add methacrylic acid (MAA) 33.0 g (0.384 mol), isobutyl methacrylate (MPA) 6.15 g (0.0433 mol), AIBN 2.21 to a 1000 ml four-necked flask equipped with a nitrogen inlet and a reflux tube. g (0.012 mol) and PGMEA 80 g were polymerized by stirring for 8 hours under a nitrogen atmosphere of 80 to 85 °C. Further, glycidyl methacrylate (MGA) 48.8 g (0.384 mol), triphenylphosphine 1.44 g (0.0055 mol) and 2,6-di-t-butyl cresol 0.055 g were placed in the flask together with PGMEA 83 g. The mixture was stirred at 80 to 85 ° C for 16 hours to obtain a (meth) acrylate resin containing a polymerizable double bond. A peak of 1409 cm ^-1 (vinyl) and 1186 cm ^-1 (carboxyl) was observed by IR measurement of the obtained (meth) acrylate resin containing a polymerizable double bond. This confirmed that it was a (meth) acrylate resin containing a polymerizable double bond. Further, the resin solution 2 adjusted to have a solid content of 30% was diluted with PGMEA. The resin P2 contained in the obtained resin solution 2 had an average molecular weight Mw of 19,000 and an acid value of 100 mgKOH/g. The glass transition temperature of the resin is 35 to 40 °C.

(Synthesis Example 3)

Add 18.9 g (0.219 mol) of methacrylic acid (MAA), 38.4 g (0.384 mol) of methyl methacrylate, and MMA with carboxyl group at one end in a 1000 ml four-necked flask equipped with a nitrogen introduction tube and a reflux tube. /MPA copolymer (reactive polymer monomer obtained by weight-average molecular weight of 6000 to give glycidyl methacrylate a molar excess) 7.84 g (about 0.0013 mol), AIBN 1.00 g (0.0052 m) And PGMEA 120 g, which was stirred under a nitrogen atmosphere of 80 to 85 ° C for 8 hours to be polymerized. In the flask, 46.9 g (0.219 mol) of glycidyl methacrylate, 1.44 g (0.0055 mol) of triphenylphosphine and 0.055 g of 2,6-di-t-butyl cresol were placed together with PGMEA 80 g. The mixture was stirred at 80 to 85 ° C for 16 hours to obtain a (meth) acrylate resin containing a polymerizable double bond. A peak of 1409 cm ^-1 (vinyl) and 1186 cm ^-1 (carboxyl) was observed by IR measurement of the obtained (meth) acrylate resin containing a polymerizable double bond. This confirmed that it was a (meth) acrylate resin containing a polymerizable double bond. Further, the resin solution 3 having a solid content of 30% was adjusted by PGMEA dilution. The resin P3 contained in the obtained resin solution 3 had an average molecular weight Mw of 47,000 and an acid value of 4 mgKOH/g. The glass transition temperature of the resin is from 60 to 65 °C.

[Example 1]

As shown in Table 2, the resin solution (P1 solution) obtained in Synthesis Example 1 was used, and a surfactant BYK333 (manufactured by BYK) was added thereto, and PGMEA as a solvent was added thereto to obtain a solution having a solid content of 20% by weight. The filter of μm was subjected to pressure filtration at 0.5 kg/cm ² to obtain a desired transparent resin composition. Then, it was printed by slit coating in an easy-bonding surface of easy-bond PET (A4100, Toyo-made A4100, film thickness: 100 μm) so that the film thickness after drying was 5 μm, and 1200 Pa × 20 seconds, 400 Pa at normal temperature. The film was dried under vacuum for 30 seconds, and then dried by heating on a hot plate at 70 ° C for 5 minutes to obtain a PET film with a transparent resin layer. The surface of the coating film of the transparent resin layer is non-tacky. In addition, its light transmission at 400 nm exceeds 95%.

Then, using the Konica Minolta inkjet head KM512M (with 14 pp sprayable nozzle 512 holes), the above-described colored inkjet ink G1 was applied to the transparent resin layer of the PET film with the transparent resin layer described above. The μm was drawn at intervals of 1 dot, and the diffusion of the colored region formed on the transparent resin layer was observed. After the drawing, the film was dried at 70 ° C for 3 minutes on a hot plate, exposed to 1500 mJ (I line standard) by an ultraviolet exposure machine, and annealed at 70 ° C for 10 minutes to measure the diffusion of the droplets on the resin layer. The diffusion diameter immediately after the drawing was 94 μm, and almost no diffusion of the colored region was observed even after the drying, exposure, and annealing steps, and the cross-sectional shape was a convex shape.

Then, as shown in Fig. 3(a), the PET film with the transparent resin layer prepared in the same manner as described above is drawn in the first drawing so as to separate 50 μm by the distance between the centers in the Y direction. The G1 ink is inked and continuously drawn in such a manner that the drawing direction (Y direction) is separated by a spacing of 302 μm. After 5 seconds, as shown in Figure 3 (b), in the second In the second drawing, two drops are arranged in the same manner in the X direction from the first drawing center-to-center distance by 45 μm, and a total of four drops are formed to form a colored region in one pixel to form a colored region, and the diffusion of the colored coating film is observed. After the drawing, the film was dried at 70 ° C for 3 minutes, exposed to 1500 mJ by an ultraviolet exposure machine, and further heat-treated at 70 ° C for 10 minutes to observe the diffusion of the colored region. The colored region at this time is diffused into the shape shown in Fig. 5(b) and diffused in a 150 μm square (Xmax = 150 μm and Ymax = 150 μm in Fig. 5(b)). Further, the contact line of the droplets with the transparent resin film is also maintained in the drying/exposure/heat treatment, and there is no case where four drops are diffused into a circular shape.

In addition, in order to observe the cross-sectional shape, a PET film with a transparent resin layer prepared separately was printed in the same manner as described above, and 15 pl × 8 drops were printed in the range of 120 μm × 120 μm as shown in Fig. 6 (in Fig. 6). For this reason, Xmax = 120 μm and Ymax = 120 μm), and this was formed into a 3 × 3 square, and the surface shape was observed using a probe type surface shape measuring instrument along a dotted line shown in Fig. 7 (a). The results are shown in Figure 7(b). As a result, it was found that there was no intersection of the colored coating film at the boundary portion between the one squares composed of 15 pl × 8 drops, and the overlap of the diffusion of the transparent resin layer was observed between the colored coating film and the colored coating film. This indicates that the transparent resin in the colored ink penetrates into the transparent resin layer, and on the other hand, the colored coating film is fixed on the surface of the transparent resin layer.

[Comparative Example 1]

In the same manner as in Example 1, the G1 ink was directly formed in the same manner as in the first embodiment, and the drying, exposure, and heat treatment were carried out in the same manner as in the case of the easy-bonded surface of the Toyobo-bonded PET (A4100) (the surface on which the ink was easily spread). The droplets on PET have a diffusion diameter of more than 150 μm and wet diffusion, and the boundary surface is not fixed.

Further, in the same manner as in the first embodiment, a colored region was formed so as to overlap four drops of G1 ink and to form a colored region in one pixel. The diffusion diameter of the drawn droplets was more than 150 μm square, and the diffusion shape of each colored region was compared, and the shape was not fixed.

[Comparative Example 2]

In the general PET surface (surface without the easy-bonding treatment) of the Toyobo-bonded PET (A4100), a transparent resin layer was not formed, and the colored region was drawn in the same manner as in Example 1, and the diffusion was observed as shown in Fig. 5 (a). ), diffused into a colored area of a circular shape.

[Example 2]

Using the resin solution (P2 solution) prepared in Synthesis Example 2, the transparent resin composition was adjusted in the composition shown in Table 2, and the film thickness was formed in the same manner as in Example 1 on the easy-bonding surface of the easy-bonded PET (A4100) manufactured by Toyobo Co., Ltd. 5 μm transparent resin layer. The surface of the dried transparent resin layer is not sticky, and its light transmittance at 400 nm exceeds 95%.

Then, in the same manner as in Example 1, the G1 ink was directly drawn on the PET film with the transparent resin layer (but the center-to-center distance in the Y direction was separated by 45 μm), and drying, exposure, and heat treatment were similarly performed. just After the drawing and after the heat treatment, the colored region on the transparent resin layer was in the shape shown in Fig. 5(b), and it was diffused in a 150 μm square. Further, the contact line of the droplets with the transparent resin layer does not occur even if the dots which are diffused into a circular shape by 4 drops in the drying/exposure/heat treatment.

[Examples 3 to 4]

As shown in Examples 3 and 4 of Table 2, the resin solution (P1 solution) prepared in Synthesis Example 1 and the resin solution (P2 solution) prepared in Synthesis Example 2 were respectively used, and a new one as a polyfunctional acrylic monomer was used. Pentaerythritol tetraacrylate (PE-4A, manufactured by Kyoeisha Chemical Co., Ltd.) (Q1), and Irgacure 907 (manufactured by BASF) as a photoinitiator and BYK333 as a surfactant, mixed in the composition shown in Table 2, and prepared A transparent resin composition was used to form a transparent resin layer having a thickness of 5 μm in the same manner as in Example 1 except that the transparent resin composition was bonded to the easy-bonded PET (A4100). The surface of the dried transparent resin layer is not sticky, and its light transmittance at 400 nm exceeds 97%.

Then, in the same manner as in the first embodiment, the G1 ink was repeatedly drawn by four dots at a dot interval of 50 μm, and drying, exposure, and heat treatment were similarly performed. Immediately after the drawing and after the heat treatment, the diffusion diameter of the droplets on the PET is the colored region at this time, and is the shape shown in Fig. 5(b), and the diffusion is in the range of 150 μm square. Further, the contact line of the droplets with the transparent resin layer is maintained even in the drying/exposure/heat treatment, and the fact that 4 drops are diffused into a circular shape does not occur.

[Examples 5 to 9]

As shown in Examples 5 to 9 of Table 2, a resin solution was used. (P2 to P4 solution) A transparent resin composition having a composition shown in Table 2 was prepared, and a transparent resin layer having a thickness of 5 μm was formed in the same manner as in Example 1 on the easy-bonding surface of Toyo Seisene-bonded PET (A4100). The surface of the dried transparent resin layer is not sticky, and its light transmittance at 400 nm exceeds 97%.

Then, in the same manner as in the first embodiment, the G1 ink was directly drawn by four dots in a dot interval of 50 μm or 45 μm (Y direction) and 45 μm (X direction), and drying, exposure, and heat treatment were similarly performed. Immediately after the drawing and after the heat treatment, the diffusion diameter of the droplets on the PET is the colored region at this time, and is the shape shown in Fig. 5(b), and the diffusion is in the range of 150 μm square. Further, the contact line of the liquid droplets with the transparent resin film is maintained even in the drying/exposure/heat treatment, and the fact that 4 drops are diffused into a circular shape does not occur.

[Example 10]

A saturated polyester resin TP217 (P4; manufactured by Nippon Synthetic Chemical Co., Ltd., a molecular weight of 16,000, a glass transition point of 40 ° C, and a concentration of 40%) was used, and in the same manner as in Example 1, it was transparent to the easy-bonded surface of Toyobo Easily Bonded PET (A4100). Resin layer. The surface of the dried transparent resin layer is not sticky, and its light transmittance at 400 nm exceeds 95%.

Then, in the same manner as in the first embodiment, the G1 ink 4 was directly drawn so as to be overlapped, and drying, exposure, and heat treatment were similarly performed. Immediately after the drawing and after the heat treatment, the diffusion diameter of the droplets on the PET is the colored region at this time, and is the shape shown in Fig. 5(b), and the diffusion is in the range of 150 μm square. In addition, the droplets are kept even during drying/exposure/heat treatment The contact line of the transparent resin film does not occur when four drops are diffused into a circular shape.

Hereinafter, in the examples 11 to 20, a color filter of a 6-inch panel having a size of 1 pixel of a TFT of 151 μm × 153 μm and corresponding to 600 × 800 pixels was fabricated. Then, the color filters are bonded to the transparent substrate side of an electrophoretic monochrome display electronic book Kindle (D701, manufactured by Amazon) using microcapsules to obtain a color display device.

[Example 11]

The above-described colored inks R1, G1, B1 were transparent to the PET film with a transparent resin layer prepared in Example 1 using a Konica Minolta inkjet head KM512M (14 pl equipped with a sprayable nozzle 512 hole). The resin layer was formed into a colored area of 4 dots by the drawing method shown in Example 1, and as shown in Fig. 4, it was formed at intervals of 153 μm in the X direction (two times at intervals of 306 μm), and 151 in the Y direction. The μm interval (formed twice at intervals of 302 μm) separates and draws the colors to form a continuous colored region, thereby producing a 6-inch color filter. After drawing, it was dried on a hot plate at 70 ° C for 3 minutes, exposed to 1500 mJ (I-line standard) by an ultraviolet exposure machine, and further heat-treated at 70 ° C for 10 minutes. During the processing, the three colors of the respective droplets were not overlapped, and the convex shape was displayed. The area of the colored region was 50% or more and 90% or less for the pixel opening of the TFT substrate.

Using the color filter obtained above, a 6-inch monochrome electronic paper panel having a number of pixels of 151 μm × 153 μm and 600 × 800 pixels is attached via an acrylic transparent adhesive, thereby producing a color display element. Pieces. When the pixels of each color are lit, no color mixture between the colored pixels is seen. Further, the reflectance of the color display elements was more than 60% as compared with the case where the monochrome display before the color filter was attached was 100%, and it was confirmed that a bright panel was obtained.

[Examples 12 to 20]

The PET film with the transparent resin layer formed on the above-described colored inks R1, G1, B1 for Examples 2 to 10 using Konica Minolta inkjet head KM512M (14 pl equipped with a sprayable nozzle 512 hole) was used. The transparent resin layer was formed into a colored area of 4 dots by the drawing method shown in Example 1, and as shown in FIG. 4, it was formed at intervals of 153 μm in the X direction (two times at intervals of 306 μm) and in the Y direction. A continuous colored area was drawn at 151 μm intervals (formed twice at intervals of 302 μm) to prepare a 6-inch color filter. After drawing, it was dried at 70 ° C for 3 minutes on a hot plate, exposed to 1500 mJ (I-line standard) by an ultraviolet exposure machine, and further heat-treated at 70 ° C for 10 minutes. During the processing, the three colors of the respective droplets were not overlapped at all, and the convex shape was displayed. The area of the colored region was 50% or more and 90% or less for the pixel opening of the TFT substrate.

Using the color filter obtained above, a 6-inch monochrome electronic paper panel having a number of pixels of 151 μm × 153 μm and 600 × 800 pixels is attached via an acrylic transparent adhesive, thereby producing a color display element. . When the pixels of each color are lit, no color mixture between the colored pixels is seen. Further, the reflectance of the color display element was more than 60% as compared with the case where the monochrome display before the color filter was attached was 100%, and it was confirmed that a bright panel was obtained.

[Comparative Example 3]

Easy bonding for Toyobo easy-bond PET (A4100) The transparent resin layer was not formed on the surface, and the inks of R1, G1, and B1 were drawn in a manner of striking at 1 pixel 4 in the same manner as in Example 11, and drying, exposure, and heat treatment were similarly performed. The droplets on the PET have a diffusion diameter of more than 150 μm and are wet-diffused, and a color mixture is seen.

[Example 21]

A transparent resin layer was formed on the easy-bonding surface of A4100 in the same manner as in Example 1 except that the film thickness of the dried transparent resin layer was 30 μm. The surface of the dried transparent resin layer is not sticky, and its light transmittance at 400 nm exceeds 95%.

Then, the G1 ink was directly drawn in the same manner as in Example 1, and drying, exposure, and heat treatment were carried out in the same manner. The diffusion diameter of the droplets immediately after the drawing and after the heat treatment is the colored region at this time, and is the shape shown in Fig. 5(b), and the diffusion is in the range of 150 μm square. Further, even if the contact line of the liquid droplets with the transparent resin layer is maintained in the drying/exposure/heat treatment, the fact that 4 drops are diffused into a circular shape does not occur.

[Reference Example 1]

A transparent resin layer was formed on the easy-bonding surface of A4100 in the same manner as in Example 1 except that the film thickness of the dried transparent resin film was 0.2 μm. The surface of the dried transparent resin layer is not sticky, and its light transmittance at 400 nm exceeds 95%.

Then, in the same manner as in Example 1, the G1 ink was directly drawn on the transparent resin layer film, and similarly, drying, exposure, and heat treatment were performed. As a result, the diffusion diameter of 1 droplet exceeded 150 μm, and the diffusion was wet, and the boundary surface was not fixed when 4 dots overlapped.

1‧‧‧Drive Switch

2‧‧‧Drive electrode

3‧‧‧Drive side substrate

4‧‧‧ Conductive layer

5‧‧‧Transparent substrate

6‧‧‧White particles

7‧‧‧Black particles

8‧‧‧Distributed media

9‧‧‧microcapsules

10‧‧‧Display media

11‧‧‧ color filter

12‧‧‧Support substrate with transparent resin layer

13‧‧‧Transparent resin layer

14‧‧‧Colored layer

Claims (7)

A color filter comprising a monochrome display device and a color filter used in a color display device disposed on a color filter side of the display device, wherein the color filter has a transparent resin composition a resin layer containing a resin solution in which a transparent resin is dissolved, and a colored region containing a plurality of colored inks formed by at least a liquid state at a normal temperature is formed by an inkjet method on the transparent resin layer The resin, a solid resin at room temperature, a colorant, and a solvent are essential components. The transparent resin layer absorbs only the solvent of the colored ink and the liquid resin to form a colored region, and the coloring region is not colored or transparent. The color filter according to claim 1, wherein the transparent resin layer has a thickness of 1 μm or more and 30 μm or less and a light transmittance of 95% or more in 400 nm. The color filter according to claim 1 or 2, wherein the transparent resin layer is formed on a transparent support substrate composed of a transparent film. The color filter according to claim 1, wherein the colored ink contains an ultraviolet curable component, is ejected onto the transparent resin layer by an inkjet method, and dried, and then cured by ultraviolet light to form a colored region. The color filter according to claim 1, wherein the transparent resin composition forming the transparent resin layer contains an ultraviolet curable component, and after the inkjet method is used to eject the colored ink and dried, at least by ultraviolet light. The transparent resin layer is formed. The color filter according to Item 4 or 5, wherein the ultraviolet curable component contained in the transparent resin layer and/or the colored ink contains at least a transparent acrylic resin or a polyfunctional acrylic monomer. The color filter according to claim 4, wherein a transparent resin composition-formed transparent resin layer containing 0.005 to 0.5 part by weight of the surfactant with respect to 100 parts by weight of the transparent resin composition is used.