TW201730644A - Reflective display panel and production method therefor - Google Patents

Abstract

The present invention eliminates color change that is caused by light irradiation and that has been a problem associated with the use of a pigment having a phthalocyanine skeleton when producing a reflective display panel through a process with relatively less load of light and heat, and provides a highly reliable reflective display panel and a method for producing same. The reflective display panel according to the present invention at least has, in this order: a substrate; a first electrode layer; a reflective display layer; a second electrode layer; a base material; and an ink fixation layer, wherein the ink fixation layer has a plurality of coloring parts, which are arranged in correspondence to drive units of the first electrode layer, and all or part of the plurality of the coloring parts contain a pigment having a phthalocyanine skeleton and a binder resin not having an amino group within the molecular skeleton thereof.

Description

Reflective display panel and method of manufacturing same

The present invention relates to a reflective display panel and a method of fabricating the same.

In recent years, the image display panel is mainly a liquid crystal display panel using a backlight, but has a large burden on the eyes and is not suitable for long-term continuous viewing.

As a display device having a small eye load, there is a reflective display panel in which a reflective display layer is provided between a pair of electrodes. In the same manner as the printed paper surface, the reflective display panel displays characters or images by reflected light, so that the burden on the eyes is small, and it is suitable for continuous viewing of the screen for a long time.

Nowadays, the reflective display panel is mainly composed of two-color display mainly in black and white. However, in recent years, a color filter composed of red, green and blue primary color pixels has been proposed on the reflective display layer. A display device that performs multicolor display (refer to Patent Document 1).

On the other hand, the reflective display panel uses external light for display, so the brightness (brightness) of the panel is limited, especially for color filters having color portions of three primary colors of red, green, and blue in each pixel. In the case of multi-color display, there will be color filters The reduction in luminance is conspicuous and the visibility is deteriorated, and further high brightness or high color reproducibility, high contrast, and the like are required.

For this problem, attempts have also been made to improve the visibility by arranging artificial illumination in the vicinity of the display device to ensure the visibility. However, as a result of such an attempt, damage is caused to one of the characteristics of the reflective display device, that is, low power consumption using electric power only when the display of the reflective display device is changed.

In addition to the above, there is an attempt to improve the visibility by improving the color of the coloring portion of the color filter itself. Specifically, in recent years, when a green colored portion constituting a color filter is formed, a zinc halide anthraquinone pigment (for example, CIPigment Green 58 or the like) is gradually used as a main pigment instead of the conventional copper phthalocyanine pigment. (For example, CIPigment Green 36 composed of copper beryllphin pigment or CIPigment Green 7 composed of copper azacyrite pigment, etc.).

However, the zinc halide phthalocyanine is known to be an excellent coloring agent and can also be used as a material for an organic semiconductor, and is particularly stable in the case of deaeration because it is converted into an anthraquinone radical (Patent Documents 2 and 3). Serious problems occur in the case of zinc halide anthraquinone as a colorant. That is, the absorption wavelength of the anthratriene radical is deviated from the absorption wavelength of the astaxanthin in the ground state, so that when used as a colorant, a change in color is observed. This phenomenon is remarkable when it is used in a state of being completely isolated from the air like a liquid crystal display device or a reflective display panel, and it is desired to be improved.

As an attempt to solve a phenomenon similar to this, there is a proposal to contain a compound selected from nitroso naphthols and diphenyl ketones (Patent Literature) 4). However, this technique is a technique for a color filter produced by a dyeing method using an anthocyanin stinky dye and a pigment, and in recent years, in order to be used for pigment dispersion using a finely-treated pigment as a coloring agent. The color filter produced by the method or the photolithography method or the inkjet method has many problems such as dispersibility of the pigment, photoetching suitability, and inkjet suitability.

Prior technical literature Patent literature

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

Patent Document 2 Japanese Patent No. 2949230

Patent Document 3 Japanese Patent No. 2954461

Patent Document 4 Japanese Patent No. 2661135

The present invention has been made in view of the above circumstances, and an object thereof is to provide a reflective display panel and a method of manufacturing the same that solves the problem of using an anthraquinone skeleton in the manufacture of a reflective display panel having a program having a small load of heat or light. The color change caused by the illumination of the pigment is high and the reliability is high.

One aspect of the present invention for solving the above problems is a reflective display panel having at least a reflective type of a substrate, a first electrode layer, a reflective display layer, a second electrode layer, a substrate, and an ink fixing layer. a display panel, and the ink fixing layer has a plurality of coloring portions, The coloring unit is disposed in the driving unit corresponding to the first electrode layer, and all or a part of the plurality of colored portions include a pigment having an anthraquinone skeleton and a binder resin having no amine group in the molecular skeleton.

In addition, the binder resin may be one or more selected from the group consisting of an acrylic resin, an epoxy resin, and a phenol resin.

Further, the pigment having an indoline skeleton may contain any one of C.I. Pigment Green 7, 36, 58, 59 or at least two of them.

Further, the mass average molecular weight of the binder resin may be 200 or more and 10,000 or less.

Further, the mass ratio of the pigment having an anthracycline skeleton to the binder resin in the colored portion may be 1:9 or more and 1:1 or less.

Further, the ratio of the area occupied by the coloring portion in the display unit of the reflective display layer corresponding to the driving unit of the first electrode layer may be 25% or more and 99% or less.

Another aspect of the present invention provides a method of manufacturing a reflective display panel, which is a method of manufacturing the reflective display panel, and includes a step of forming a colored portion by an inkjet method.

Alternatively, the method for manufacturing a reflective display panel includes a step of drying at a temperature lower than a glass transition point of the substrate to form a colored portion.

According to the present invention, it is possible to provide a reflective display panel which solves the color change caused by illumination when a pigment having an anthracycline skeleton is used in the manufacture of a reflective display panel having a program having a small load of heat or light. The problem is high and the reliability is high.

10‧‧‧Substrate

11‧‧‧First electrode layer

12‧‧‧Next layer

13‧‧‧Reflective display layer

14‧‧‧Second electrode layer

15‧‧‧Substrate

16‧‧‧Ink fixing layer

17‧‧‧Shading Department

18‧‧‧Protective film

19‧‧‧Display unit of reflective display layer

100‧‧‧reflective display panel

Fig. 1 is a cross-sectional view showing a reflective display panel according to an embodiment of the present invention.

Fig. 2 is a plan view showing an ink fixing layer of a reflective display panel according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail.

Fig. 1 is a cross-sectional view showing a reflective display panel 100 according to an embodiment of the present invention. Fig. 2 is a plan view showing an ink fixing layer of the reflective display panel 100 according to the embodiment of the present invention.

In the reflective display panel 100 shown in FIG. 1, the first electrode layer 11 is formed on the substrate 10, and the reflective display layer 13 is formed on the first electrode layer 11 via the adhesive layer 12. The first electrode layer 11 is arranged with a plurality of pixel electrodes, and each of the pixel electrodes is connected to the switching element, and a positive and negative voltage can be applied between the second electrode layer 14.

The second electrode layer 14, the substrate 15, the ink fixing layer 16, and the protective film 18 are sequentially laminated on the reflective display layer 13. The ink fixing layer 16 has a plurality of coloring portions 17 disposed to face the driving units of the first electrode layer 11. All or a part of the plurality of colored portions 17 contains, for example, a pigment having an anthraquinone skeleton.

The reflective display layer 13 may be a reflective liquid crystal or a cholesteric liquid crystal, an electrophoretic type (microcapsule type, etc.), a microcup type, an electrochromic type, or the like. The substrate 15 may be a light-transmitting material, and a film substrate such as a glass substrate, a PET film, or a PEN film may be used.

The ink fixing layer 16 having the colored portion 17 can be formed by photolithography of a color resist film such as a color filter for a liquid crystal display device, but has the reflective display panel 100 as in the present embodiment. In the case of the ink fixing layer 16 of the coloring portion 17 to be used, the coloring portion 17 can be formed by forming the ink fixing layer 16 and applying a plurality of inks to the ink fixing layer 16. The ink fixing layer 16 can be formed by applying a coating liquid for forming an ink fixing layer containing a resin.

As the ink fixing layer 16, a urethane resin, a polyester, an acrylic resin, a vinyl alcohol resin or the like can be used. Further, in order to improve the absorbability of the solvent of the ink, the ink fixing layer 16 may contain a porous substance such as synthetic cerium oxide or aluminum oxide. The formation of the ink fixing layer 16 can be formed by a screen printing method, an offset printing method, a spin coating method, or intermittent coating using a mold, if it is subjected to a monolithic treatment. Further, if the continuous treatment is performed by a roll to roll, the ink can be formed by a general coating technique such as die coating, comma coating, curtain coating, gravure coating, or the like. Fixed layer 16. Further, the coating liquid for forming an ink fixing layer after application can be dried. As the drying method, heating, air blowing, pressure reduction, or the like can be used. However, it is preferable to use a drying step at a temperature lower than the glass transition point of the substrate 10, and it is expected to be applied to PET which is not heat-resistant compared with glass. Substrate 10. Thereby, deformation or the like of the substrate 10 due to heat can be prevented.

As the ink application method for forming the colored portion 17 on the ink fixing layer 16, since the black matrix for partitioning the driving unit is not formed, it is necessary to apply the coating separately depending on the color. Therefore, a screen printing method, an offset printing method, an inkjet printing method, or the like can be used. Especially from easy From the viewpoint of high position and high productivity, it is preferable to eject ink to the ink fixing layer 16 by an inkjet printing method to form the coloring portion 17. In addition, the ink after coating can be dried. As the drying method, heating, blowing, depressurization, or the like can be used. However, it is preferable to use a drying step at a temperature lower than the glass transition point of the substrate 10, and it is expected to be applied to a substrate such as PET which is not heat resistant to glass. 10. Thereby, deformation or the like of the substrate 10 due to heat can also be prevented. In addition, if the drying is insufficient, the solvent in the ink acts as a catalyst, and the color change caused by the illumination of the phthalocyanine is accelerated. Therefore, even if the temperature is lower than the glass transition point of the substrate 10, It is preferred to dry under reduced pressure and the like.

As a device used in the inkjet printing method, there are a pressure conversion type and a heat conversion type depending on the ink ejection method, but it is desirable to use a pressure conversion type device. Further, the particle size of the ink of the ink jet apparatus is desirably about 5 kHz to 100 kHz. Further, the nozzle diameter of the ink jet apparatus is desirably about 5 μm to 80 μm. Further, in the ink jet apparatus, it is preferable to use a plurality of nozzles for arranging a plurality of nozzles and to provide about 60 to 500 nozzles per nozzle.

The ink used for the colored portion 17 can be formed of a coloring agent, a solvent, a binder resin, or a dispersing agent.

As a coloring agent, in recent years, vivid colors can be realized in the organic pigment used in the coloring agent of the green colored portion in the color filter, and thus the zinc halide anthraquinone pigment and CIPigment Green 58 (PG58) are gradually widely used. use. However, as described in detail in the background art, the pigment is photoreactive, so when a green colored portion as a color filter is used, it is provided in a reflective display device that is insulated from air. When placed, the color changes due to its photoreactivity. In particular, when the pigment particle diameter is gradually reduced in order to increase the contrast, this tendency becomes remarkable, and thus it becomes difficult to ensure the light resistance of the color filter having the green colored portion containing PG58.

Therefore, it is presumed that the color change of the green colored portion is caused by the anthraquinone radical anion generated by the light, and the countermeasure is reviewed. In other words, it has been found that the green pigment of the green colored portion is rapidly increased by selecting a green pigment containing a binder resin which does not promote the production of an anthraquinone radical anion to suppress the production of an anthracycline radical anion.

Therefore, the pigment having an anthraquinone skeleton of the coloring agent contained in the green coloring portion 17 to which the present invention is suitable is a copper alkaloid pigment (for example, CIPigment Green composed of a copper beryllium bromate pigment). 36 or CIPigment Green 7 or the like composed of a copper chloroanthin pigment, or a zinc halide anthraquinone pigment (for example, CIPigment Green 58, etc.). Further, it is preferable to use a copper chlorophosphorus pigment which is short in excitation state and high in light stability by irradiation.

As the coloring material of the ink other than the pigment having an indoline skeleton used in the present invention, all the pigments can be used regardless of the organic pigment, the inorganic pigment, the dye, or the like. As an appropriate one, an organic pigment can be cited, and it is especially preferable to use an excellent light resistance. Specifically, CIPigment Red 9, 19, 38, 43, 97, 122, 123, 144, 149, 166, 168, 177, 179, 180, 192, 208, 215, 216, 217, 220, 223, 224, 226, 227, 228, 240, 254, CIPigment Blue 15, 15:3, 15:6, 16, 22, 29, 60, 64, CIPigment Green 7, 36, 56, 58, 59, CIPigment Yellow 20, 24, 86, 81, 83, 93, 108, 109, 110, 117, 125, 137, 138, 139, 147, 148, 150, 153, 154, 166, 168, 185, CIPigment Orange 36, 73, CIPigment Violet 23 and so on. Further, in order to obtain a desired hue, two or more materials may be used in combination.

The solvent used in the ink of the present invention is preferably one having a surface tension of 35 mN/m or less and a boiling point of 130 ° C or more in consideration of suitability in inkjet printing. When the surface tension is more than 35 mN/m, the ink dot shape stability is remarkably adversely affected when the ink is ejected, and if the boiling point is less than 130 ° C, the drying property is remarkably high near the nozzle, and as a result, the nozzle may be caused. A tendency to cause a malfunction such as clogging.

Specific examples thereof include 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, and 2-methyl Oxyethyl acetate, 2-ethoxyethyl ether, 2-(2-ethoxyethoxy)ethanol, 2-(2-butoxyethoxy)ethanol, 2-(2-B Oxyethoxyethyl)ethyl acetate, 2-(2-butoxyethoxy)ethyl acetate, 2-phenoxyethanol, diethylene glycol dimethyl ether, etc., but not subject to The solvent may be suitably used as long as it satisfies the above conditions, and two or more solvents may be used in combination as needed.

As the binder resin which can be used in the present invention, a binder resin having no amine group in the molecular skeleton can be used, which does not promote the generation of an anthraquinone radical anion which is a cause of color change due to illumination. Examples of such a binder resin include an acrylic resin, an epoxy resin, a phenol resin, and the like, or one or more of these resins. Here, a binder resin having an amine group in a substantially molecular skeleton such as a melamine resin, a urea resin, or a guanamine resin is not preferable because it promotes color change due to illumination.

Examples of the acrylic resin include (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, and butyl (meth)acrylate. Benzyl (meth)acrylate, lauryl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, ethoxyethyl (meth)acrylate, (methyl) An alkyl (meth)acrylate such as glycidyl acrylate or an alicyclic ring such as cyclohexyl (meth)acrylate, isodecyl (meth)acrylate or dicyclopentenyl (meth)acrylate ( A polymer such as methyl acrylate, but is not limited by these. These monomers may be used alone or in combination of two or more. Further, styrene, cyclohexylmaleimide, phenylmaleimide, cyclohexylmaleimide, phenyl malazone capable of copolymerizing with these (meth) acrylates can also be obtained. A compound such as an imine, methyl maleimide, ethyl maleimide, n-butyl maleimide, lauryl maleimide or the like is copolymerized.

Further, an ethylenically unsaturated group may be added to the acrylic resin. In the method of adding an ethylenically unsaturated group to an acrylic resin, a compound containing an ethylenically unsaturated group such as acrylic acid and a carboxylic acid compound is added to an epoxy group-containing resin such as glycidyl methacrylate. Method of adding an epoxy group-containing (meth) acrylate such as glycidyl methacrylate to a resin containing a carboxylic acid such as methacrylic acid; and methacryloxyethyl isocyanate The method of adding an isocyanate group-containing (meth) acrylate to a hydroxyl group-containing resin such as hydroxy methacrylate, etc., is not limited by these examples.

As the epoxy resin, for example, glycerin-polyglycidyl ether, trimethylolpropane-polyglycidyl ether, resorcinol-diglycidyl ether, neopentyl glycol-diglycidyl ether, 1,6 are known. - hexanediol-diglycidyl ether, ethylene glycol (polyethylene glycol)-diglycidyl ether, and the like. These may be used singly or in combination of two or more.

Examples of the phenol resin include a phenol resin, a resol resin, and the like.

Further, the mass average molecular weight of the binder resin is preferably in the range of 200 or more and 10,000 or less, and more preferably in the range of 300 or more and 8,000 or less. When the mass average molecular weight of the binder resin exceeds 10,000, the fluidity of the ink is insufficient at the drying step of the colored portion 16, and the pattern flatness is poor. In addition, when the mass average molecular weight of the binder resin is less than 300, the physical properties such as the required solvent resistance and heat resistance cannot be satisfied.

Dispersants can be used to enhance the dispersion of the pigment in the solvent. As the dispersing agent, an ionic or nonionic surfactant or the like can be used. Specific examples thereof include sodium alkylbenzenesulfonate, poly fatty acid salt, fatty acid salt alkyl phosphate, tetraalkylammonium salt, and polyoxyethylene alkyl ether. Other examples include organic pigment derivatives and polyesters. The dispersing agent may be used singly or in combination of two or more kinds as necessary.

The viscosity of the ink used as the coloring portion 17 is at 1 mPa. s above 20mPa. The range below s is better, further, if it is at 5mPa. s above 15mPa. The range below s is even better. If the ink viscosity exceeds 20mPa. s, there is a tendency that the ink does not hit a predetermined position or the nozzle is clogged when the ink is ejected. On the other hand, in oil The ink viscosity is less than 1mPa. In the case of s, there is a tendency to cause scattering when the ink is ejected.

Further, the mass ratio of the pigment or dye to the binder resin in the colored portion 17 is preferably in the range of 1:9 to 1:1, and the fluidity of the ink can be adjusted by changing the amount of the resin in the ink to improve the fluidity of the ink. The concentration deviation in the colored portion 17.

Here, since the reflective display panel is generally used as a display medium using external light, the hue and density required for the colored portion are different from those of the transmissive display panel of the liquid crystal display. The tendency is lower and the color reproduction range is smaller.

Therefore, the pigment which is a coloring component contained in the ink tends to be less, but if the amount of the binder resin is higher than 90% by mass based on the total mass of the pigment or the dye and the binder resin, the necessary amount of liquid is changed. In addition, the influence of the increase in viscosity due to the addition of the resin causes poor fluidity of the ink, and the center of the colored portion of the colored portion formed is thicker than the periphery of the colored portion.

On the other hand, when the amount of the binder resin is less than 50% by mass based on the total mass of the pigment or the dye and the binder resin, the coloring component contained in the ink is relatively large, and the color density is increased, so it is necessary to use a solvent (volatile). When the component is diluted or formed in a small amount of droplets, the coloring portion is formed by a small amount of liquid droplets. As a result, when the solvent is diluted with a solvent (volatile component), the fluidity of the ink is large, and the amount of ink dripping is also increased. It is thicker than the center of the colored portion 17, and when the colored portion 17 is formed with a small amount of liquid droplets, a gap or the like is formed due to an increase in the interval between the ink droplets, and an appropriate coloring portion 17 cannot be formed.

Next, the color display of the reflective display panel 100 will be described based on the operation principle. The reflective display panel 100 has, for example, a colored portion 17 and a non-colored portion (transparent portion) that are disposed opposite to the driving unit of the first electrode layer 11 on the reflective display layer 13 that displays white and black. Further, in this case, the reflective display layer 13 may be a reflective display medium that displays white and black, and the display mode of the display medium is not limited.

The portion of the reflective display layer 13 that faces the driving unit of the first electrode layer 11 is all white, or only the portion of the reflective layer 13 that reflects the corresponding colored portion 17 is displayed in white, and becomes the colored portion 17. The color in which the hue and the non-colored portion are mixed in white or black shows a color similar to the hue of the coloring portion 17; only the portion of the corresponding colored portion 17 of the reflective display layer 13 is black, and only the non-colored portion is penetrated. The light is reflected, so that it becomes a white display; the portion of the reflective display layer 13 that faces the driving unit of the first electrode layer 11 is all black, and all of the light is not reflected, but becomes a black display.

At this time, the color combination of the colored portion 17 can be freely changed in accordance with the use thereof. In the case of multi-color display, a combination of red and indigo, magenta and green, yellow and blue, and the like, and a two-color combination of complementary colors may be used. Any color combination can be used as long as it satisfies the complementary color relationship that becomes white by color mixing. In addition, the full-color display generally uses three colors of red, green, and blue, or cyan, magenta, and yellow. However, in the case where all of the colored portions 17 are set to white display, as long as the color combination is white, it is not Specially limited. Further, in the case of monochrome display, a desired color such as red, blue, magenta or the like can be used. In the present invention, it is particularly suitable for a coloring portion having a green color which is a hue of a pigment having an anthraquinone skeleton.

Further, the coloring portion 17 disposed to face the driving unit of the first electrode layer 11 is not particularly limited as long as it is arranged in an isotropic manner. As shown in FIG. 2, the ratio of the area occupied by the coloring portion 17 in the display unit 19 of the reflective display layer 13 corresponding to the driving unit of the first electrode layer 11 is preferably 25% or more and 99% or less. When the area ratio of the colored portion is small (less than 25% in terms of the area ratio of the colored portion 17), the sharpness at the time of display of each color is poor, and the contrast between the white/black display and each colored display (shading ratio) cannot be obtained. When the area ratio of the colored portion is large (greater than 99% in the area ratio of the colored portion 17), the colored portions 17 are easily brought into contact with each other during the ink jet method, which may cause a problem such as color mixing.

[Examples]

Hereinafter, examples and comparative examples of the present invention will be described, but the present invention is not limited to the examples.

(Example 1)

Indium tin oxide (ITO) as the second electrode layer 14 and an electrophoretic display medium as the reflective display layer 13 are sequentially formed on the substrate 15 formed of a PET substrate. Next, the first electrode layer 11 is formed on the substrate 10 formed of glass, and the first electrode layer 11 and the reflective display layer 13 are bonded to each other via the subsequent layer 12. On the substrate 15 to be bonded thereto, a polyester resin-based receiving liquid NS-141LX (Gaosong Oil Co., Ltd.) was continuously applied using a comma coater, and then dried by a vacuum dryer. In minutes, an ink fixing layer 16 having an average film thickness of 10 μm was formed.

Next, a dispersion of the colorant is prepared. The coloring pigment contained in the coloring agent used in the colored portion 17 is a pigment shown in Table 1. According to the formulation shown in Table 1, the pigment dispersion was prepared by dispersing the pigment by a bead mill and sufficiently mixing the chains.

An epoxy resin (jER-1001, manufactured by Mitsubishi Chemical Corporation) and a diethylene glycol monoethyl ether acetate as an organic solvent are added to the dispersion obtained in the above manner. The green ink shown in Table 2 was prepared by thorough stirring.

Next, the ink fixing layer 16 was coated with an inkjet printing device equipped with a 12 pl, 180 dpi (180 dots per 2.54 cm) head (manufactured by Seiko Instruments Co., Ltd.) to apply the ink of the coloring material to a predetermined position. Then, it was dried by a vacuum dryer for 5 minutes to form a colored portion 17 and a non-colored portion.

Finally, a protective film 18 is formed thereon to produce a reflective display device having a green colored portion.

(Examples 2, 3, Comparative Examples 1 to 3)

In the same manner as in Example 1, a reflective display device having green colored portions of Examples 2 and 3 and Comparative Examples 1 to 3 was produced in accordance with the combination of the green pigment and the binder resin shown in Table 3.

(light resistance evaluation)

The prepared reflective display device was irradiated with a luminosity weathering tester Ci35A (manufactured by ALTAS Co., Ltd.) under the conditions of an illuminance of 0.5 mW/cm ² (340 nm) and a temperature of 40 ° C for 168 hours to obtain a microscopic spectrophotometer OSP- SP100 (manufactured by Olympus Optical Co., Ltd.) measured the spectral characteristics before and after the irradiation, determined the color difference (ΔE*ab), and observed the appearance after the test by a microscope, and evaluated the light resistance. The criterion for determining the light resistance is "+": △E*ab≦3, "-": △E*ab>3.

The following conclusions can be seen from the results shown in Table 3. In other words, it is known that a reflective display device having a colored portion using a pigment having an anthraquinone skeleton is resistant to light by containing a resin having no amine group in a molecular skeleton which does not promote the production of an anthraquinone radical anion. Sex has improved. It is also known that the use of copper anthraquinone can improve light resistance compared to the use of zinc azacysin.

On the other hand, in Comparative Examples 1 to 3 containing a resin having an amine group in the molecular skeleton, light resistance was deteriorated. Further, in Comparative Example 2 in which a zinc halide phthalocyanin having low photostability was used, light resistance was particularly inferior.

As described above, when the colored portion contains a pigment having an anthraquinone skeleton and a binder resin having no amine group in the molecular skeleton, it is possible to obtain a coloring portion excellent in light resistance, and it is possible to obtain reliability even when oxygen is isolated. Excellent reflective display panel.

[Industrial availability]

The present invention is applicable to a reflective display device.

Claims (9)

A reflective display panel having at least a reflective display panel having a substrate, a first electrode layer, a reflective display layer, a second electrode layer, a substrate, and an ink fixing layer, wherein the ink fixing layer has a plurality of coloring portions The colored portion is disposed corresponding to the driving unit of the first electrode layer, and all or a part of the plurality of colored portions contain a pigment having an anthraquinone skeleton and a binder resin having no amine group in the molecular skeleton. The reflective display panel of claim 1, wherein the binder resin is one or more selected from the group consisting of acrylic resins, epoxy resins, and phenol resins. The reflective display panel of claim 1 or 2, wherein the pigment having an anthraquinone skeleton comprises any one of C.I. Pigment Green 7, 36, 58, 59, or at least two of the same. The reflective display panel according to any one of claims 1 to 3, wherein the binder resin has a mass average molecular weight of 200 or more and 10,000 or less. The reflective display panel according to any one of claims 1 to 4, wherein the colored portion contains a dye or pigment and a binder resin in a mass ratio of 1:9 to 1:1. The reflective display panel according to any one of claims 1 to 5, wherein a mass ratio of the pigment having an anthocyanin skeleton to the binder resin in the colored portion is 1:9 to 1:1. The reflective display panel according to any one of claims 1 to 6, wherein a ratio of an area occupied by the colored portion of the display unit of the reflective display layer corresponding to the driving unit of the first electrode layer is 25% or more 99% or less. A method of manufacturing a reflective display panel according to any one of claims 1 to 7, comprising the step of forming the colored portion by an inkjet method. A method of manufacturing a reflective display panel according to any one of claims 1 to 7, comprising the step of drying at a temperature below a glass transition point of the substrate to form the colored portion. .