JP2007047541A - Sheet for display device using self-organized honeycomb structure film, manufacturing method thereof, and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet for display device using a self-organized honeycomb structure film which is very easily and formed at a low cost without requiring complicated manufacturing equipment, a manufacturing method thereof, and a display device. <P>SOLUTION: In the sheet for display device, holes of the self-organized honeycomb structure film disposed on a conductive film are filled with an electrophoretic material and an electrostatic moving material and are sealed up. The manufacturing method of the sheet for display device includes steps of; applying the solution of a hydrophobic polymer and an amphiphilic polymer onto a substrate; forming the self-organized honeycomb structure film by spraying gas having prescribed relative humidity onto the surface of solution applied onto the substrate, substantially at a fixed flow rate; filling holes of the honeycomb structure film with the electrophoretic material and the electrostatic moving material; and sealing up the holes of the honeycomb structure film. In the display device, the conductive film is disposed on the honeycomb structure film of the sheet for display device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sheet for a display device using a honeycomb structured film by self-organization, a manufacturing method thereof, and a display device.

  Until now, various devices that display character data and image data by holding an electro-optical material between opposed electrodes and changing the optical characteristics of the material by applying a voltage between the electrodes are available. It has been developed and put into practical use. Typical examples are a liquid crystal display device using a liquid crystal material and an organic EL element using an organic electroluminescent material.

  On the other hand, an electrophoretic display device using an electrophoretic material (for example, see Patent Documents 1, 2, and 3) and an electrostatic movement display device using an electrostatic moving material (for example, see Patent Document 4). Attention has been paid. In addition to excellent display characteristics, these display devices have extremely low power consumption, can be bent thinly like paper, can be easily made large in area, and can be manufactured at low cost. Application is expected.

  In order to realize electronic paper, it is necessary to hold an electro-optic material in a matrix that is lightweight and flexible. For example, a method of encapsulating an electro-optical material in a microcapsule in an aqueous medium (see, for example, Patent Document 2), a partition or a spacer is formed using photolithography, and the electro-optical material is formed in a microcell partitioned by them. (For example, see Patent Documents 3 and 4).

  However, when a microcapsule is used as a matrix, an aqueous medium or an electrolyte deteriorates the physical properties of the electro-optic material during encapsulation, so that the electro-optic material is limited or a large number of micro-capsules are formed between the opposing electrodes. To arrange the capsules without gaps, a very high technique is required. In addition, when using photolithography, a complicated manufacturing apparatus is required, which increases the equipment cost, and it is necessary to clean and remove the uncured photoresist with a solvent after the light irradiation. There are concerns about the impact on the environment.

  On the other hand, a micropattern formation method by self-organization has attracted attention (see, for example, Non-Patent Document 1). This is a method in which a polymer solution is applied on a glass substrate under high humidity and then a gas is blown onto the surface thereof to evaporate the solvent and form a honeycomb structure using condensed water droplets as a mold. Since this method uses micro water droplets that naturally condense from the air and a polymer that naturally precipitates from the solution, it does not require a complicated manufacturing apparatus and can be formed very easily and inexpensively. There is.

As an application example of the micropattern forming method by self-organization, for example, an optical functional film using a honeycomb structure (see, for example, Patent Document 5) or a material in which pores of a honeycomb structure are filled with a magnetic material (for example, Patent Document) 6) has been reported. However, in any case, the pores of the honeycomb structure have a pore diameter of 1 μm or less and cannot be applied to a matrix holding an electro-optic material.
Japanese Patent Publication No. 50-15115 JP-A 64-86116 JP 2005-37851 A JP 2004-341123 A JP 2003-294905 A JP 2003-318010 A Ken Tanaka and two others, “Nanomaterials by Self-Organization”, Special Feature 3-Nanotechnology / Biotechnology and other next-generation attention technologies and microfabrication equipment and systems, "M &E", Industrial Research Committee, August 2003, p. 190-195

  Under the circumstances described above, the problem to be solved by the present invention is that it is lightweight and flexible by using a self-organized honeycomb structure film that can be formed very easily and inexpensively without requiring a complicated manufacturing apparatus. It is to provide a display device sheet using a honeycomb structure film by self-organization, a manufacturing method thereof, and a display device.

  As a result of intensive studies to solve the above problems, the present inventor, as a matrix for holding an electro-optic material, in a display device in which an electro-optic material is held between opposing electrodes, a honeycomb structure film by self-organization is used. The present invention was completed by finding that a lightweight and flexible display device can be realized by application.

  That is, the present invention provides a sheet for a display device in which an electro-optic material is held on a conductive film that functions as one electrode. Such a sheet for a display device is characterized in that the electro-optic material is filled and sealed in each hole of the honeycomb structure film by self-organization disposed on the conductive film. In the present invention, the “electro-optical material” means an electrophoretic display dispersion containing at least one kind of electrophoretic particles in a dispersion medium and / or a static electrostatic particle comprising at least two kinds of electrostatic transfer particles. It means a powder fluid for electromigration display.

  In the sheet for a display device of the present invention, the honeycomb structure film preferably has a porosity of 30% or more and 80% or less, a pore diameter of preferably 20 μm or more and 100 μm or less, and preferably has a variation coefficient of the pore diameter. 30% or less. The pores of the honeycomb structure film are preferably arranged substantially in a single layer.

  The present invention also provides a method of manufacturing the display device sheet. In this production method, a hydrophobic polymer and an amphiphilic polymer are used, and the amount of the amphiphilic polymer used is 1% by mass or more, 50%, based on the total mass of the hydrophobic polymer and the amphiphilic polymer. A step of applying a solution dissolved in a hydrophobic organic solvent on the substrate so as to be less than or equal to mass%, and a gas having a relative humidity of 40% or more and 95% or less on the surface of the solution applied on the substrate; Spraying at a substantially constant flow rate, evaporating the organic solvent, condensing water vapor on the surface of the solution, evaporating the generated water droplets, and forming a self-organized honeycomb structure film; and the honeycomb The method includes a step of filling each pore of the structure film with an electro-optic material and a step of sealing the pores of the honeycomb structure membrane filled with the electro-optic material.

  In the method for producing a sheet for a display device according to the present invention, the flow rate of the gas is preferably 0.01 m / s or more and 1 m / s or less.

  The present invention also provides a display device in which an electro-optical material is held between opposing electrodes. Such a display device is characterized in that a conductive film serving as the other electrode is disposed on the honeycomb structure film of the display device sheet. Hereinafter, unless otherwise specified, “display device” means “electrophoretic display device” using an electrophoretic material as an electro-optical material, and “electrostatic transfer material” as an electro-optical material. When it means `` electrostatic transfer display device '', when it means each individual display device together, and when it means a display device that uses both an electrophoretic material and an electrostatic transfer material as an electro-optical material is there.

  The display device sheet of the present invention uses a self-organized honeycomb structure film as a matrix for holding an electro-optic material, and therefore can be manufactured very easily and inexpensively. A large amount of flexible display devices can be provided at a low price. In the method for manufacturing a sheet for a display device according to the present invention, since the honeycomb structure film is formed from the polymer solution by self-organization, the matrix holding the electro-optical material can be manufactured very easily and inexpensively. Since the electro-optic material is filled in the pores after the structure film is formed, the electro-optic material is not limited or its physical properties are not lowered as in the case of using the microcapsule. The display device of the present invention has excellent display characteristics, is a lightweight and flexible display device, and can be provided in large quantities at a low price. Therefore, it can be widely used as a new display means.

≪Sheet for display device≫
The display device sheet of the present invention is a display device sheet in which an electro-optical material is held on a conductive film functioning as one electrode, and the electro-optical material is disposed on the conductive film. Each of the pores of the honeycomb structure film formed by self-organization is filled and sealed.

  FIG. 1 is a partially sectional perspective view showing an example of a sheet for a display device of the present invention. However, the illustration of the plastic film or conductive film that seals the pores of the honeycomb structure film is omitted. In the display device sheet 10, an electro-optical material 30 is held on a conductive film 20. In the conductive film 20, a conductive layer 24 is formed on a base film 22. The electro-optic material 30 is filled in each hole 50 of the honeycomb structure film 40 formed on the conductive film 20.

  The sheet for a display device of the present invention provides a monochrome (monochrome) display device as long as the pores of the honeycomb structure film are filled with the same color, and the electro-optic material exhibits different colors. Is filled, a multi-color display device is provided. For example, as shown in FIG. 1, three holes 52, 54, and 56 adjacent to each other absorb electrogreen material 32 that absorbs green and exhibits reddish purple, and electricity that absorbs red and exhibits blue-green. Character data and image data can be displayed in multiple colors (colors) by filling the optical material 34 and the electro-optical material 36 that absorbs blue-violet and exhibits a yellow color. Normally, when all of the electro-optic materials 32, 34, and 36 are in the display state, black is displayed, but it may not be so clear. In this case, if the fourth hole 58 adjacent to the holes 54 and 56 is filled with the electro-optic material 38 exhibiting black, the black can be displayed more vividly. Alternatively, the holes 52, 54, and 56 are filled with the electro-optic material 50 that exhibits the same color, and color filters that transmit red, blue, and green light are disposed corresponding to the holes, and character data or The image data may be displayed in multiple colors (colors).

  Hereinafter, the case where the electro-optic material is an electrophoretic material and the case where it is an electrostatic transfer material will be described separately.

<Electrophoretic materials>
First, the electrophoretic material will be described. Here, the “electrophoretic material” means an electrophoretic display dispersion containing at least one kind of electrophoretic particles in a dispersion medium. Hereinafter, a display device using an electrophoretic material as an electro-optical material may be referred to as an “electrophoretic display device”.

<Electrophoretic particles>
The dispersion liquid for electrophoretic display contains at least one kind of electrophoretic particles in a dispersion medium. Here, “electrophoretic particles” are solid particles having electrophoretic properties in a dispersion medium, that is, have a positive or negative charge in the dispersion medium, and substantially pass through the dispersion medium in response to an external electric field. Solid particles that move to When the electrophoretic particles are solid particles that do not have electrophoretic properties in the dispersion medium or have insufficient electrophoretic properties, for example, treatment with a coupling agent having a chargeable group is performed as necessary. For example, a sufficient electrophoretic property may be imparted by a conventionally known method.

  As solid particles constituting the electrophoretic particles, for example, pigment particles are used. Alternatively, polymer particles colored with a dye or polymer particles containing a pigment may be used. These solid particles may be used alone or in combination of two or more. Of these solid particles, pigment particles are particularly preferred.

  Examples of pigments used for the electrophoretic particles include inorganic pigments such as titanium oxide, barium sulfate, zinc oxide, and zinc white in white systems; yellow iron oxide, cadmium yellow, titanium yellow, chrome yellow, and yellow lead in yellow systems. Inorganic pigments such as first yellow, insoluble azo compounds such as first yellow, condensed azo compounds such as chromophthal yellow, azo complex salts such as benzimidazolone azo yellow, condensed polycyclics such as flavans yellow, hansa yellow, naphthol Organic pigments such as yellow, nitro compounds and pigment yellow; in the case of orange, organic pigments such as inorganic pigments such as molybdate orange, azo complex salts such as benzimidazolone azo orange, and condensed polycycles such as perinone orange; In red, inorganic pigments such as Bengala and Cadmium Red Dyeing lakes such as madareki, soluble azo compounds such as lake red, insoluble azo compounds such as naphthol red, condensed azo compounds such as chromophthalscar red, condensed polycycles such as thioindigo bordeaux, sinker red Organic pigments such as quinacridone pigments such as Y and Hosta Palm Red, azo pigments such as Permanent Red and Fast Slow Red; in the case of purple, inorganic pigments such as manganese violet, dyed lakes such as rhodamine lake, dioxazine violet, etc. Organic pigments such as condensed polycycles; In blue, inorganic pigments such as bitumen, ultramarine blue, cobalt blue and cerulean blue, phthalocyanines such as phthalocyanine blue, indanthrenes such as indanthrene blue, alkali blue, etc. Organic pigments In green systems, inorganic pigments such as emerald green, chrome green, chromium oxide, and viridian, azo complex salts such as nickel azo yellow, nitroso compounds such as pigment green and naphthol green, and organic pigments such as phthalocyanines such as phthalocyanine green The black type includes inorganic pigments such as carbon black, titanium black and iron black, and organic pigments such as aniline black. The pigment particles composed of these pigments may be used alone or in combination of two or more. Of these pigments, white pigments such as titanium oxide and black pigments such as carbon black and titanium black are particularly suitable.

  In addition, when using titanium oxide, the kind is not specifically limited, As long as it is generally used as a white pigment, any titanium oxide of a rutile type or an anatase type may be used, for example. In consideration of fading of the colorant due to photocatalytic activity, rutile type titanium oxide having low photocatalytic activity is preferable. Further, in order to reduce the photocatalytic activity, Si treatment, Al treatment, Si—Al treatment, Zn—Al treatment or the like may be performed.

  Examples of the polymer used for the electrophoretic particles include a polyolefin polymer, a polyhalogenated olefin polymer, a polyester polymer, a polyurethane polymer, a polystyrene polymer, an acrylic polymer, an epoxy polymer, a melamine polymer, a urea polymer, Examples include phenolic polymers, polyamide polymers, and silicone polymers. Here, “polymer” means not only a homopolymer but also an alternating copolymer, a random copolymer, a block copolymer, and a graft copolymer obtained by copolymerizing 50 mol% or less of another copolymerizable monomer. Includes coalescence. These polymer particles may be used alone or in combination of two or more. Examples of the dye that colors these polymer particles include the following dyes listed as dyes that can be added to the following dispersion medium. Examples of the pigment to be contained in these polymer particles include the pigments listed above as pigments used for the electrophoretic particles.

  The average particle diameter of the electrophoretic particles is not particularly limited. For example, the volume average particle diameter is preferably 0.1 μm, more preferably 0.15 μm, and still more preferably 0.2 μm. The upper limit is preferably 5 μm, more preferably 4 μm, and even more preferably 3 μm. If the average particle diameter is less than 0.1 μm, sufficient chromaticity cannot be obtained, the contrast is lowered, and the display may be unclear. Conversely, when the average particle diameter exceeds 5 μm, it is necessary to increase the coloring degree of the particles more than necessary, and the amount of pigment used increases or electrophoresis is applied at the portion where voltage is applied for display. Rapid movement of particles may be difficult, and the response speed (display response) may be reduced.

  When the electrophoretic particles are dispersed in a dispersion medium (that is, a solvent in which the electrophoretic particles are dispersed when used in a dispersion for electrophoretic display), the zeta potential exhibited by the dispersion is not particularly limited. For example, it is an absolute value, preferably 30 mV or more, more preferably 40 mV or more, and still more preferably 50 mV or more. The zeta potential may be positive or negative as long as the absolute value is large, and is not particularly limited. When the absolute value of the zeta potential is 30 mV or more, display characteristics such as display responsiveness and contrast are greatly improved when used in an electrophoretic display device. Regarding the polarity of the zeta potential, for example, in a one-particle electrophoretic display device, at least one kind of electric potential in which the zeta potential indicated by the dispersion liquid is either positive or negative when dispersed in a dispersion medium. Electrophoretic particles are used, and in a two-particle electrophoretic display device, when dispersed in a dispersion medium, at least one type of electrophoretic particles having a positive zeta potential indicated by the dispersion liquid and dispersed in the dispersion medium In this case, at least one type of electrophoretic particle having a negative zeta potential exhibited by the dispersion is used. Here, the zeta potential is measured for a dispersion obtained by dispersing at least one kind of electrophoretic particles in a dispersion medium in a one-particle electrophoretic display device, and in a two-particle electrophoretic display device, This is carried out for each dispersion obtained by dispersing at least two kinds of electrophoretic particles independently in a dispersion medium.

  The electrophoretic particles may be dispersed as they are in the dispersion medium used for the dispersion for electrophoretic display. However, the surface treatment may be performed by reacting a coupling agent on the surface or coating the surface with a polymer. It may be dispersed after going. In this case, the electrophoretic particles are preferably pigment particles and are surface-treated with a coupling agent or a polymer. In the present invention, the electrophoretic particles thus surface-treated may be simply referred to as electrophoretic particles.

  The surface-treated electrophoretic particles may be isolated as electrophoretic particles, or when the same type of dispersion medium as that used in the electrophoretic display liquid is used for the surface treatment, the electrophoretic particles are obtained after the surface treatment. The dispersion may be used as it is, or after adding a dispersion medium as appropriate and mixing well, and then, for use in the production of a dispersion for electrophoretic display. In order to isolate the electrophoretic particles, for example, the dispersion obtained after the surface treatment is centrifuged, and the supernatant is discarded, and only the precipitate is collected as the electrophoretic particles. Further, the electrophoretic particles thus obtained are redispersed in a dispersion medium, centrifuged, and only the sediment is collected, and the operation is performed at least once, preferably a plurality of times, more preferably 3 times or more. The electrophoretic particles may be washed. Centrifugation conditions may be set as appropriate according to the equipment to be used, and are not particularly limited, but are used when a fine powder dispersion is centrifuged to collect a settled powder. What is necessary is just to use 15-30 minutes by normal conditions, for example, 10,000G.

<Coupling agent>
Examples of the coupling agent that reacts with the surface of the electrophoretic particles include a coupling agent having a charging group, a coupling agent having a long-chain alkyl group, or a coupling agent having a charging group and a long-chain alkyl group. Can be used. If a coupling agent having a chargeable group is used, the chargeability of the electrophoretic particles is increased, and the electrophoretic particles can be quickly moved at a portion where voltage is applied for display, and the response speed (display) Responsiveness) is increased, and if a coupling agent having a long-chain alkyl group is used, the effect of improving the dispersibility of the electrophoretic particles in the dispersion medium can be obtained.

  Examples of the coupling agent having a charging group include 3-aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-ureidopropyltriethoxysilane, 3-ureidopropyltrimethoxysilane, and 3-aminopropyl. Trimethoxysilane, 3-aminopropyl-tris (2-methoxy-ethoxy-ethoxy) silane, N-methyl-3-aminopropyltrimethoxysilane, N-aminoethyl-3-aminopropyl-trimethoxysilane, diaminosilane, N-aminoethyl-3-aminopropylmethyldimethoxysilane, triaminopropyl-trimethoxysilane, 3-chloropropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-cyanopropyltriethoxysilane, vinyl trimethyl Rosilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltri (2-methoxyethoxy) silane, hexamethyldisilazane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyl Trimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, methyltri (methacryloyloxyethoxy) silane, methyltri (glycidyloxy) silane, 3-glycidoxypropyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltri Methoxysilane, 3-methacryloxypropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, N-β- (N-vinylbenzylaminoethyl) -γ-amino Propyltrimethoxysilane hydrochloride, octadecyldimethyl [3- (trimethoxysilyl) propyl] ammonium chloride, γ-chloropropylmethyldichlorosilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, methyldichlorosilane, dimethylchlorosilane, dimethyl Vinylchlorosilane, methylvinyldichlorosilane, methylchlorodisilane, triphenylchlorosilane, methyldiphenylchlorosilane, diphenyldichlorosilane, methylphenyldichlorosilane, phenyltrichlorosilane, chloromethyldimethylchlorosilane hexamethyldisilazane, isopropyltri (n-aminoethyl- Aminoethyl) titanate, tetraisopropylbis (dioctyl phosphite) titanate, Raokuchirubisu (ditridecylphosphite) titanate, tetra (2,2-diallyl-1-butyl) bis (ditridecyl) phosphite titanate, etc. trifluoropropyl trimethoxysilane. These coupling agents may be used alone or in combination of two or more.

  Examples of the coupling agent having a long-chain alkyl group include propyltrimethoxysilane, butyltrimethoxysilane, hexyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, octadecyltrimethoxysilane, Propyl dodecyltrichlorosilane, butyltrichlorosilane, hexyltrichlorosilane, decyltrichlorosilane, dodecyltrichlorosilane, hexadecyltrichlorosilane, octadecyltrichlorosilane, isopropyltriisostearoyl titanate, isopropyltrioctanoyl titanate, acetoalkoxyaluminum diisopropinate, etc. Can be mentioned. These coupling agents may be used alone or in combination of two or more. Among these coupling agents, decyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, octadecyltrimethoxysilane, propyldodecyltrichlorosilane, decyltrichlorosilane, dodecyltrichlorosilane, hexadecyltrichlorosilane, octadecyltrichlorosilane Isopropyl triisostearoyl titanate, isopropyl trioctanoyl titanate, acetoalkoxyaluminum diisopropylate and the like are particularly suitable.

  Examples of the coupling agent having a charging group and a long-chain alkyl group include octadecyldimethyl-3- (trimethoxylyl) propylammonium chloride, dodecafluorooctyltrichlorosilane, isopropyltridodecylbenzenesulfonyl titanate, isopropyl (dioctyl sulfate). ) Titanate. These coupling agents may be used alone or in combination of two or more. Of these coupling agents, octadecyldimethyl-3- (trimethoxylyl) propylammonium chloride, dodecafluorooctyltrichlorosilane and the like are particularly suitable.

  Examples of the method of reacting the coupling agent on the surface of the electrophoretic particles include, for example, a method in which a dispersion medium, electrophoretic particles, and a coupling agent are placed in an ultrasonic bath and ultrasonically dispersed while stirring, a paint shaker, and a ball mill. A dispersion method using a dispersing device such as a sand grind mill, a dry method in which a coupling agent is sprayed with dry air or nitrogen gas while forcibly stirring the dispersion medium and electrophoretic particles with a V blender, etc. Examples include a wet method in which a coupling agent is added to a slurry in which electrophoretic particles are appropriately dispersed, and a spray method in which the coupling agent is sprayed while vigorously stirring the preliminarily heated dispersion medium and the electrophoretic particles. .

<Coating polymer>
If the surface of the electrophoretic particles is coated with a polymer, the effect of improving the dispersibility of the electrophoretic particles in the dispersion medium and the moisture resistance can be obtained. Examples of the polymer that coats the surface of the electrophoretic particles include polyolefin polymers, polyhalogenated olefin polymers, polyester polymers, polyurethane polymers, polystyrene polymers, acrylic polymers, epoxy polymers, melamine polymers, urea. System polymers and the like. Here, “polymer” means not only a homopolymer but also an alternating copolymer, a random copolymer, a block copolymer, and a graft copolymer obtained by copolymerizing 50 mol% or less of another copolymerizable monomer. Includes coalescence. These polymers may be used alone or in combination of two or more.

  In particular, when the surface of the electrophoretic particles is coated with a polymer formed by radical polymerization, a polymerizable monomer having a reactive group, a polymerizable monomer having a charging group, a polymerizable monomer having a long-chain alkyl group, Other polymerizable monomers can be used.

  Examples of the polymerizable monomer having a reactive group include the following formula:

Polymerizable monomers having an aziridine group such as 2-vinyl-2-oxazolidine, 2-vinyl-4-methyl-2-oxazolidine, 2-vinyl-5-methyl-2-oxazolidine, 2-vinyl-4- Ethyl-2-oxazolidine, 2-vinyl-5-ethyl-2-oxazolidine, 2-isopropenyl-2-oxazolidine, 2-isopropenyl-4-methyl-2-oxazolidine, 2-isopropenyl-5-methyl-2 -Oxazolidine, 2-isopropenyl-4-ethyl-2-oxazolidine, 2-isopropenyl-5-ethyl-2-oxazolidine, 2-isopropenyl-4,5-dimethyl-2-oxazolidine-containing polymerization Monomer; acrylic acid amide, methacrylic acid amide; N-hydroxymethyl Kurylamide, N-hydroxyethylacrylamide, N-hydroxybutylacrylamide, N-hydroxyisobutylacrylamide, N-hydroxy-2-ethylhexylacrylamide, N-hydroxycyclohexylacrylamide, N-hydroxymethylmethacrylamide, N-hydroxyethylmethacrylamide, N Polymerizable monomers having an N-hydroxyalkylamide group such as -hydroxybutyl methacrylamide, N-hydroxyisobutyl methacrylamide, N-hydroxy-2-ethylhexyl methacrylamide, N-hydroxycyclohexyl methacrylamide;

などで示されるエポキシ基を有する重合性モノマー；下記式：

A polymerizable monomer having an epoxy group represented by the formula:

などで示されるチオエポキシ基（エピスルフィド基）を有する重合性モノマー；下記式：

A polymerizable monomer having a thioepoxy group (episulfide group) represented by:

A polymerizable monomer having an isocyanato group represented by These polymerizable monomers may be used alone or in combination of two or more.

  Examples of the polymerizable monomer having a charging group include chlorostyrene, styrenesulfonic acid, acrylic acid, trifluoroethylene acrylate, nitrile acrylate, methacrylic acid, trifluoroethylene methacrylate, nitrile methacrylate, glycidyl acrylate, Examples thereof include glycidyl methacrylate, tert-butylaminoethyl methacrylate, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, chlorohydroxypropyl acrylate, chlorohydroxypropyl methacrylate, trichloroethyl acrylate, and trichloroethyl methacrylate. These polymerizable monomers may be used alone or in combination of two or more.

  Examples of the polymerizable monomer having a long chain alkyl group include pentyl acrylate, isopentyl acrylate, neopentyl acrylate, hexyl acrylate, octyl acrylate, decyl acrylate, undecyl acrylate, dodecyl acrylate, lauryl acrylate, Stearyl acrylate, hexadecyl acrylate, heptadecyl acrylate, nonadecyl acrylate, aralkyl acrylate, behenyl acrylate, heptacil acrylate, nonacyl acrylate, doteracyl acrylate, pentyl methacrylate, isopentyl methacrylate, neopentyl methacrylate, methacrylic acid Hexyl, octyl methacrylate, decyl methacrylate, undecyl methacrylate, dodecyl methacrylate, lauryl methacrylate, stearyl methacrylate , Hexadecyl methacrylate, heptadecyl methacrylate, nonadecyl methacrylate, arachidyl methacrylate, behenyl methacrylate, Heputashiru methacrylate, Nonashiru methacrylic acid and methacrylic acid Doderiashiru is. These polymerizable monomers may be used alone or in combination of two or more.

  Examples of other polymerizable monomers include styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, α-methyl styrene, p-methoxy styrene, p-tert-butyl styrene, p-phenyl styrene, o -Styrene monomers such as chlorostyrene, m-chlorostyrene, p-chlorostyrene; ethylene, propylene, butylene, vinyl chloride, methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, Examples include methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, and isobutyl methacrylate. These polymerizable monomers may be used alone or in combination of two or more.

  Examples of the method of coating the surface of the electrophoretic particles with a polymer include a method in which the above polymerizable monomer is subjected to suspension polymerization in a state where solid particles constituting the electrophoretic particles are dispersed in an appropriate solvent. Can be mentioned. In this case, it is preferable to treat the surface of the solid particles with the coupling agent as described above prior to suspension polymerization because the polymerizable monomer can be reacted efficiently on the surface of the solid particles.

<Dispersion for electrophoretic display>
The electrophoretic particles are used in a dispersion for electrophoretic display. The dispersion liquid for electrophoretic display contains at least one kind of electrophoretic particles in a dispersion medium. More specifically, when used in a one-particle electrophoretic display device, the dispersion liquid is dispersed in a dispersion medium. When the dispersion liquid contains at least one type of electrophoretic particles having a positive or negative zeta potential and is used in a two-particle electrophoretic display device, when dispersed in a dispersion medium It contains a combination of at least one type of electrophoretic particle having a positive zeta potential exhibited by the dispersion and at least one type of electrophoretic particle having a negative zeta potential exhibited by the dispersion when dispersed in a dispersion medium. ing.

  The lower limit of the concentration of electrophoretic particles in the dispersion (the mass% of the particles relative to the mass of the dispersion) is preferably 1% by mass, more preferably 2% by mass, and even more preferably 5% by mass. The upper limit is preferably 25% by mass, more preferably 23% by mass, and still more preferably 20% by mass. When the concentration of the electrophoretic particles is less than 1% by mass, sufficient chromaticity cannot be obtained, the contrast is lowered, and the display may be unclear. On the contrary, when the concentration of the electrophoretic particles exceeds 25% by mass, the viscosity of the dispersion liquid becomes high, so that the dispersion process becomes difficult, and aggregation of the electrophoretic particles occurs in a portion where a voltage is applied for display. It may occur and the response speed (display responsiveness) may decrease.

<Dispersion medium>
As the dispersion medium for dispersing the electrophoretic particles, a conventionally known dispersion medium generally used for a dispersion for electrophoretic display can be used, and is not particularly limited. For example, an organic solvent is preferable.

  Examples of the organic solvent used as the dispersion medium include benzene hydrocarbons such as benzene, toluene, o-xylene, m-xylene, p-xylene, mixed xylene, ethylbenzene, hexylbenzene, dodecylbenzene, and phenylxylylethane. Aromatic hydrocarbons; paraffinic hydrocarbons such as n-hexane and n-decane, isoparaffinic hydrocarbons such as Isopar (Isopar, manufactured by Exxon Chemical), olefinic hydrocarbons such as 1-octene and 1-decene, Aliphatic hydrocarbons such as naphthenic hydrocarbons such as cyclohexane and decalin; hydrocarbon mixtures derived from petroleum and coal such as kerosene, petroleum ether, petroleum benzine, ligroin, industrial gasoline, coal tar naphtha, petroleum naphtha and solvent naphtha; Dichloromethane, chloro Rum, carbon tetrachloride, 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, trichlorofluoroethane, tetrabromoethane, dibromotetrafluoroethane, tetrafluorodiiodoethane, 1,2-dichloroethylene, trichloroethylene, tetrachloroethylene, trichlorofluoroethylene, chlorobutane, chlorocyclohexane, chlorobenzene, o-dichlorobenzene, bromobenzene, iodomethane, diiodomethane, iodoform and other halogenated hydrocarbons; esters such as ethyl acetate and butyl acetate Ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; alcohols such as methanol, ethanol, isopropanol, octanol and methyl cellosolve S; and the like; carbon disulfide; fluorine-based solvents such as hydrofluoroether; dimethyl silicone oil, silicone oils such as methyl phenyl silicone oil. These organic solvents may be used alone or in combination of two or more. Of these organic solvents, long-chain alkylbenzenes such as hexylbenzene and dodecylbenzene, phenylxylylethane, and the like are preferable because they have a high boiling point and flash point and are hardly toxic.

  The amount of the dispersion medium used is not particularly limited. For example, the lower limit is preferably 40% by mass, more preferably 50% by mass, and still more preferably 60% by mass with respect to the total amount of the resulting dispersion. Moreover, the upper limit is preferably 95% by mass, more preferably 92% by mass, and still more preferably 90% by mass. When the amount of the dispersion medium used is less than 40% by mass, the viscosity of the dispersion becomes high, and the electrophoretic properties of the electrophoretic particles may be lowered. On the other hand, when the amount of the dispersion medium used exceeds 95% by mass, the concentration of the electrophoretic particles becomes low, and when used in an electrophoretic display device, display characteristics such as contrast may be deteriorated.

  When the dispersion medium for electrophoretic display is used in a one-particle electrophoretic display device, the dispersion medium is preferably colored with, for example, a dye in order to increase the contrast of the electrophoretic particles. On the contrary, it is preferably colorless and transparent so as not to inhibit the contrast of at least two kinds of electrophoretic particles having different optical reflection characteristics, for example, color tone.

<Dye>
When the dispersion medium is colored, as the dye used for coloring, for example, an oil-soluble dye is preferable, and an azo dye and an anthraquinone dye are more preferable particularly from the viewpoint of ease of use. As an azo dye and an anthraquinone dye, for example, an azo compound such as oil yellow 3G (manufactured by Orient Chemical Co., Ltd.) as a yellow dye; an azo compound such as First Orange G (manufactured by BASF AG) as an orange dye Anthraquinones such as Macrolex Blue RR (manufactured by Bayer AG) as blue dyes; Anthraquinones such as Sumiplast Green G (manufactured by Sumitomo Chemical Co.) as green dyes; Oil brown as brown dyes Azo compounds such as GR (manufactured by Orient Chemical Industry Co., Ltd.); As red dyes, azo compounds such as Oil Red 5303 (manufactured by Arimoto Chemical Industry Co., Ltd.) and Oil Red 5B (manufactured by Orient Chemical Industry Co., Ltd.) Compounds: Oil Violet # 730 (Orient Chemical Industries) as purple dye Anthraquinones such as Sudan Black X60 (BASF AG), anthraquinone Macrolex Blue FR (Bayer AG) and azo Oil Red XO (Kanto Chemical) (Made by Co., Ltd.). These dyes may be used alone or in combination of two or more.

  Although the usage-amount of dye is not specifically limited, For example, with respect to 100 mass parts of dispersion media, the minimum becomes like this. Preferably it is 0.1 mass part, More preferably, it is 0.5 mass part, More preferably, it is 1 The upper limit is preferably 10 parts by mass, more preferably 9 parts by mass, and still more preferably 8 parts by mass. If the amount of the dye used is less than 0.1 parts by mass, the dispersion medium may be insufficiently colored, and sufficient contrast with the electrophoretic particles may not be obtained. Conversely, if the amount of the dye used exceeds 10 parts by mass, the dye will be used more than necessary, and the material cost may increase.

  The dispersion for electrophoretic display can contain other components as needed in addition to the electrophoretic particles and the dispersion medium. Examples of other components include a dispersant, a charge control agent, and a viscosity modifier.

<Dispersant>
The dispersant is used, for example, to assist the dispersion of the electrophoretic particles in the dispersion medium. Examples of the dispersant that can be added to the dispersion medium include an anionic surfactant that can be dissolved in the dispersion medium, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, and a fluorosurfactant. Sorbitan fatty acid ester surfactants such as sorbitan sesquiolate, dispersants such as block polymers and graft polymers, and various coupling agents. These dispersants may be used alone or in combination of two or more.

  The amount of the dispersant used is not particularly limited. For example, the lower limit is preferably 0.1 parts by mass, more preferably 0.2 parts by mass, and still more preferably, with respect to 100 parts by mass of the dispersion medium. The upper limit is preferably 10 parts by mass, more preferably 8 parts by mass, and even more preferably 5 parts by mass. When the amount of the dispersant used is less than 0.1 parts by mass, the effect of dispersing the electrophoretic particles may be small. Conversely, when the amount of the dispersant used exceeds 10 parts by mass, the effect of dispersing the electrophoretic particles is saturated, and the dispersant is used more than necessary, which may increase the material cost.

<Charge control agent>
The charge control agent is used, for example, to adjust the electrophoretic properties of the electrophoretic particles in the dispersion medium. Examples of the charge control agent that can be added to the dispersion medium include chromium complexes such as Bontron E-81 (manufactured by Orient Chemical Co., Ltd.); zinc complexes such as Bontron E-84 (manufactured by Orient Chemical Co., Ltd.); Aluminum complexes such as -88 (manufactured by Orient Chemical Co., Ltd.); phenol condensates such as Bontron E-89 (manufactured by Orient Chemical Co., Ltd.); azine compounds such as Bontron N-01 (manufactured by Orient Chemical Co., Ltd.); Azochrome complexes such as Bontron S-34 (manufactured by Orient Chemical Co., Ltd.); iron complexes such as Bontron X-11 (manufactured by Orient Chemical Co., Ltd.); These charge control agents may be used alone or in combination of two or more.

  The amount of the charge control agent used is not particularly limited. For example, the lower limit is preferably 0.01 parts by weight, more preferably 0.05 parts by weight, and still more preferably, with respect to 100 parts by weight of the dispersion medium. Is 0.1 part by mass, and the upper limit thereof is preferably 5.0 parts by mass, more preferably 3.0 parts by mass, and still more preferably 2.0 parts by mass. When the amount of the charge control agent used is less than 0.01 parts by mass, the effect of adjusting the electrophoretic properties may be small. On the contrary, if the amount of the charge control agent used exceeds 5.0 parts by mass, the effect of adjusting the electrophoretic property is saturated and the charge control agent is used more than necessary, which may increase the material cost. is there.

<Viscosity modifier>
The viscosity modifier is used, for example, to prevent sedimentation of electrophoretic particles in the dispersion medium. Viscosity modifiers that can be added to the dispersion medium include vegetable oil polymerization compounds such as Disparon 101 (manufactured by Enomoto Kasei Co., Ltd.), polyether ester type surfactants such as Disparon 3350 (manufactured by Enomoto Kasei Co., Ltd.), Hydrogenated castor oil-based compounds such as Disparon 305 (manufactured by Enomoto Kasei Co., Ltd.), Aliphatic amide waxes such as Disparon 6500 (manufactured by Enomoto Kasei Co., Ltd.), Benton 760 (manufactured by Elementis PLC) Organic modified smectite and the like can be mentioned. These viscosity modifiers may be used alone or in combination of two or more.

  When the viscosity modifier is used, the amount used is not particularly limited. For example, the lower limit is preferably 0.01 parts by mass, more preferably 0.05 parts by mass with respect to 100 parts by mass of the dispersion medium. Parts, more preferably 0.1 parts by weight, and the upper limit is preferably 10 parts by weight, more preferably 5 parts by weight, and even more preferably 1 part by weight. When the usage-amount of a viscosity modifier is less than 0.01 mass part, the effect which adjusts a viscosity may be few. On the other hand, when the amount of the viscosity modifier used exceeds 10 parts by mass, the viscosity of the dispersion becomes too high and the electrophoretic properties of the electrophoretic particles may be hindered.

<Manufacture of dispersion for electrophoretic display>
A dispersion liquid for electrophoretic display containing at least one kind of electrophoretic particles in a dispersion medium is produced by dispersing the electrophoretic particles in the dispersion medium.

  The electrophoretic particles may be isolated and used in the form of powder, or may be used as a dispersion containing the electrophoretic particles in a predetermined dispersion medium. In the latter case, the dispersion means a mixture containing electrophoretic particles and a dispersion medium, and may be in any form from a liquid with a low viscosity to a slurry with a high viscosity. The dispersion medium used for such a dispersion liquid is preferably the same type of dispersion medium as that used for the dispersion liquid for electrophoretic display.

  As a method for dispersing the electrophoretic particles in the dispersion medium, a conventionally known fine particle dispersion technique can be used. As a dispersion method, for example, a method of performing a dispersion treatment after adding or adding an electrophoretic particle to a dispersion medium; a dispersion treatment after adding or adding a dispersion medium to an electrophoretic particle Method of performing: Method of performing dispersion treatment after mixing electrophoretic particles and dispersion medium or while mixing; Adding remaining dispersion medium to dispersion liquid in which electrophoretic particles are dispersed in a part of dispersion medium Or a method of further dispersing treatment while adding, or the like. The dispersion treatment may be performed using any conventionally known means. For example, an ultrasonic homogenizer, a paint shaker, a ball mill, a sand grind mill, a V blender, or the like can be used.

  When the electrophoretic particles are treated with the coupling agent simultaneously with the dispersion treatment, for example, the coupling agent is sprayed with dry air or nitrogen gas while forcibly stirring the dispersion medium and the electrophoretic particles with a V blender or the like. The dry method, the electrophoretic particles are appropriately dispersed in a dispersion medium, the wet method in which a coupling agent is added to the slurry, the preheated dispersion medium, and the electrophoretic particles are coupled with vigorous stirring. The spray method etc. which spray an agent can be used.

<Electrostatic transfer material>
Next, the electrostatic transfer material will be described. Here, the “electrostatic transfer material” means an electrostatic transfer display powder fluid composed of at least two types of electrostatic transfer particles. Hereinafter, a display device using an electrostatic transfer material as an electro-optical material may be referred to as an “electrostatic transfer display device”.

<Electrostatically moving particles>
The powder fluid for electrostatic movement display is composed of at least two kinds of electrostatic movement particles. Here, “electrostatic transfer particles” means solid particles having electrostatic mobility even in the absence of a dispersion medium (for example, in a gas), that is, for example, even in the absence of a dispersion medium (for example, (In gas) means solid particles that are positively or negatively charged by contact between particles and move substantially in response to an external electric field. In the case where solid particles that do not have electrostatic mobility or are insufficient in electrostatic mobility are used as the electrostatic migration particles, for example, a charge control agent may be added or charged groups may be added as necessary. Sufficient electrostatic mobility may be imparted by a conventionally known method such as a treatment with a coupling agent having a viscosity. The at least two types of electrostatic moving particles are a combination of at least one type of positively charged electrostatic moving particles and at least one type of negatively charged electrostatic moving particles.

  As the solid particles constituting the electrostatic transfer particles, for example, pigment particles are used. Alternatively, polymer particles colored with a dye or polymer particles containing a pigment may be used. These solid particles may be used alone or in combination of two or more. Of these solid particles, pigment particles are particularly preferred.

  Examples of the pigment used for the electrostatic transfer particles include the pigments listed above as pigments used for the electrophoretic particles. The pigment particles composed of these pigments may be used alone or in combination of two or more. Of these pigments, white pigments such as titanium oxide and black pigments such as carbon black and titanium black are particularly suitable.

  Examples of the polymer used for the electrostatic transfer particles include the above-described polymers listed as polymers used for the electrophoretic particles. Here, “polymer” means not only a homopolymer but also an alternating copolymer, a random copolymer, a block copolymer, and a graft copolymer obtained by copolymerizing 50 mol% or less of another copolymerizable monomer. Includes coalescence. These polymer particles may be used alone or in combination of two or more. Examples of the dye that colors these polymer particles include the dyes listed above as dyes that can be added to the dispersion medium in which the electrophoretic particles are dispersed. Examples of the pigment to be contained in these polymer particles include the pigments listed above as pigments used for the electrophoretic particles.

  The average particle diameter of the electrostatically moving particles is not particularly limited, but for example, the volume average particle diameter, the lower limit is preferably 0.1 μm, more preferably 0.5 μm, still more preferably 1 μm, In addition, the upper limit is preferably 50 μm, more preferably 40 μm, and even more preferably 30 μm. When the average particle diameter is less than 0.1 μm, aggregation and adhesion of electrostatic transfer particles occur, and the contrast decreases. The display may be unclear. On the contrary, if the average particle diameter exceeds 50 μm, when the voltage is turned off after applying the voltage for display, the electrostatically moving particles easily move, and the display stability may be lowered. is there.

  The charge amount exhibited by each electrostatically moving particle when at least two kinds of electrostatically moving particles are brought into contact with each other is not particularly limited. For example, the room temperature is 5 ° C. to 35 ° C., and the normal humidity is 45% to 85%. In an atmosphere of (relative humidity), in absolute amount, the lower limit is preferably 10 μC / g, more preferably 20 μC / g, still more preferably 30 μC / g, and the upper limit is preferably 150 μC / g. More preferably, it is 120 μC / g, and further preferably 100 μC / g. When the charge amount is less than 10 μC / g, since the electrostatic mobility is low, a sufficient display density cannot be obtained in the display portion, and the display quality may be deteriorated. On the other hand, when the charge amount exceeds 150 μC / g, electrostatically moving particles may be aggregated or adhered, the contrast may be lowered, and the display may be unclear. Regarding the polarity of the charge amount, the electrostatic display device has at least one type of positively charged (that is, positive charge amount) electrostatically moving particles and at least one type of negatively charged (that is, negatively charged). Electrostatic transfer particles having a negative charge amount) are used.

  The electrostatic transfer particles may be mixed as they are, but the surface treatment may be performed by reacting a coupling agent on the surface, treating the surface with a charge control agent, or coating the surface with a polymer. You may mix after going. In this case, it is preferable that the electrostatic transfer particles are pigment particles and are surface-treated with a coupling agent or a charge control agent. In the present invention, the electrostatically-moving particles subjected to the surface treatment in this way may be simply referred to as electrostatically-moving particles.

  As the coupling agent to be reacted with the surface of the electrostatic transfer particle, for example, a coupling agent having a charging group can be used. If a coupling agent having a chargeable group is used, the chargeability of the electrostatically moving particles is increased, and the electrostatically moving particles can be moved quickly and easily at the part where voltage is applied for display. The effect that (display responsiveness) becomes high is acquired. Examples of the coupling agent having a chargeable group and the reaction method thereof include the above-described coupling agents having a chargeable group enumerated in the case of electrophoretic particles and the reaction method thereof.

  If the surface of the electrostatic transfer particles is treated with a charge control agent, the electrostatic mobility can be adjusted appropriately. As the charge control agent, conventionally known charge control agents can be used. For example, nigrosine dyes, rhodamine dyes, triphenylmethane dyes, chromium-containing metal complexes, molybdate chelates, quaternary ammonium salts, Examples include alkoxyamines, alkylamides, phosphorus compounds, tungsten compounds, fluorine-based surfactants, salicylic acid metal salts, and metal salts of salicylic acid derivatives. These charge control agents may be used alone or in combination of two or more.

  If the surface of the electrostatic transfer particles is coated with a polymer, the moisture resistance of the electrostatic transfer particles can be improved. Examples of the polymer and the coating method for coating the surface of the electrostatic transfer particle include the above-described polymers listed in the case of electrophoretic particles and the coating method thereof.

<Powder fluid for electrostatic movement display>
The electrostatic moving particles are used in a powder fluid for electrostatic movement display. The electrostatic fluid display powder fluid contains at least two kinds of electrostatic fluid particles. More specifically, the fluids are positively charged when they have different optical reflection characteristics such as color tone and come into contact with each other. Each of them contains at least one kind of electrostatic moving particles and negatively charged electrostatic moving particles.

  The lower limit of the mass ratio of the positively charged electrostatic moving particles to the negatively charged electrostatic moving particles is preferably 10/100, more preferably 20/100, and even more preferably 30/100. The upper limit is preferably 100/10, more preferably 100/20, and still more preferably 100/30. If the mass ratio of the electrostatic transfer particles is less than 10/100, the number of positively charged electrostatic transfer particles is too small. Conversely, if the mass ratio of the electrostatic transfer particles exceeds 100/10, the charge is negative. In any case, there are cases where the contrast is lowered and the display becomes unclear.

<Manufacture of powder fluid for electrostatic transfer display>
The powder fluid for electrostatic movement display containing at least two kinds of electrostatic moving particles is produced by mixing the electrostatic moving particles.

  The electrostatic transfer particles may be isolated and mixed in powder form, or may be produced as a dispersion containing the electrostatic transfer particles in a dispersion medium, and after mixing these dispersions, the dispersion medium May be removed to form a powder. In the latter case, the dispersion means a mixture containing electrostatic transfer particles and a dispersion medium, and may be in any form from a liquid with a low viscosity to a slurry with a high viscosity. Examples of the dispersion medium used for the dispersion liquid include the dispersion media as described above as the dispersion medium used for the dispersion liquid for electrophoretic display.

  As a method of mixing the electrostatically moving particles, a conventionally known fine particle mixing technique can be used. As a mixing method, for example, a method in which electrostatic transfer particles are sequentially added to or mixed with a mixing container; mixing is performed; other electrostatic transfer particles are added to a dispersion in which electrostatic transfer particles are dispersed. After or after dispersion treatment with addition, a method in which the dispersion medium is removed from the obtained dispersion liquid to form a powder; the dispersion liquid in which the electrostatic transfer particles are dispersed is transferred to another electrostatic transfer Examples of the method include a method in which the dispersion medium is added to the particles or after being dispersed while being added, and then the dispersion medium is removed from the obtained dispersion to form a powder. The mixing and dispersion treatment may be performed using any conventionally known means. For example, an ultrasonic homogenizer, a paint shaker, a ball mill, a sand grind mill, a V blender, or the like can be used.

  In the case where the electrostatic transfer particles are treated with the coupling agent simultaneously with mixing, for example, the dispersion agent and the electrostatic transfer particles are forcibly stirred with a V blender or the like, and the coupling agent is dried with dry air or nitrogen gas. Spraying dry method, Electrostatic transfer particles are dispersed in a dispersion medium appropriately, wet method of adding a coupling agent into a slurry, vigorously stirred dispersion medium and electrostatic transfer particles, etc. A spray method of spraying the coupling agent can be used.

<Honeycomb structure film by self-organization>
The self-organized honeycomb structure film is disposed between the opposing electrodes and functions to hold the electro-optic material in the pores. Here, “self-organization” means that the system itself forms an ordered structure without giving information on the structure from the outside.

  In practice, a solution in which a hydrophobic polymer and an amphiphilic polymer are dissolved in a hydrophobic organic solvent at a predetermined ratio is applied onto a substrate, and a predetermined relative humidity is applied to the surface of the solution applied onto the substrate. By spraying a gas having a substantially constant flow rate to evaporate the organic solvent, to condense water vapor on the surface of the solution and to evaporate the generated water droplets, a large number of pores are substantially continuous and regular. A honeycomb structure film arranged in a regular manner is formed. The formation mechanism of the honeycomb structure film is estimated as follows, for example, but is not intended to be any limitation. First, the water vapor in the gas is condensed by the latent heat when the solvent evaporates to form water droplets, which adhere to the surface of the solution applied on the substrate. At this time, the amphiphilic polymer reduces the surface tension between the water droplet and the hydrophobic organic solvent, and prevents the water droplet from fusing into a large mass. Water droplets are transported to the boundary of the solution by the convection and transverse capillary force generated in the solution and arranged in the closest packing, and the water droplet is fixed on the substrate by the receding of the solution surface as the solvent evaporates. . Finally, the water droplets evaporate to form a honeycomb structure film in which a large number of pores are substantially continuously and regularly arranged using the water droplet arrangement as a template.

  In the honeycomb structure film formed by self-organization, “honeycomb structure” means that pores having substantially constant shapes and pore diameters are substantially continuously and regularly arranged. More specifically, when the honeycomb structure is planar and forms a single layer, a plurality of pores are arranged so as to surround one pore in the plane of the membrane, and the honeycomb structure is three-dimensional and complex. In the case of forming a layer, the above-described array of holes is laminated in the thickness direction of the film. In any case, a close-packed structure is preferable. In addition, in the sheet | seat for display apparatuses of this invention, it is preferable that the void | hole is arranged in a single layer substantially.

  A hydrophobic polymer is used as a main component of the honeycomb structure film by self-organization. Here, the “hydrophobic polymer” means a polymer having no hydrophilic portion or hydrophilic side chain in the main chain skeleton. The hydrophobic polymer that can be used is not particularly limited as long as it is a polymer that does not have a hydrophilic portion or a hydrophilic side chain in the main chain skeleton. For example, polyethylene, polypropylene, polyisobutylene, polyisoprene, etc. Olefin polymers; vinyl polymers such as polyvinyl chloride, polyvinylidene chloride, polystyrene, poly-N-vinylcarbazole, polyvinyl acetate, polyacrylonitrile, polymethacrylonitrile, polymethyl vinyl ether; polymethyl acrylate, polyethyl acrylate, poly Acrylic polymers such as methyl methacrylate and polyethyl methacrylate; polyamide 6 (poly-ε-caprolactam), polyamide 66 (polyhexamethylene adipamide), polyamide 610 (polyhexamethylene Polyamide) such as polyamide 612, polyamide 12, polyamide 11, polyamide MXD6; polyester such as polycaprolactone, polyethylene terephthalate, polybutylene terephthalate, polycyclohexyldimethylene terephthalate, polyethylene naphthalate, polybutylene naphthalate; bisphenol A and phosgene Polycarbonate obtained by interfacial polycondensation with bisphenol A and transesterification of bisphenol A and diphenyl carbonate; polyarylate obtained by polycondensation of bisphenol A and aromatic dicarboxylic acid; by polycondensation of pyromellitic acid anhydride and aromatic diamine Polyimide obtained by polycondensation of polyimide obtained, trimellitic acid and aromatic diamine, 4,4 ′-[isopropylidenebis ( p-phenyleneoxy)] polyimide such as polyetherimide obtained by polycondensation of diphthalic dianhydride and aromatic diamine; polysulfone obtained by polycondensation of dichlorodiphenylsulfone and bisphenol A, dichlorodiphenylsulfone and dihydroxydiphenyl Polyethersulfone obtained by polycondensation with sulfone, polyphenylene ether obtained by oxidative polymerization of 2,6-dimethylphenol, polyether such as polyetheretherketone obtained by polycondensation of dihalogenobenzophenone and hydroquinone; polydimethyl And polysiloxanes such as siloxane, polydipropylsiloxane, and polydiphenylsiloxane. Here, unless otherwise specified, the “polymer” is not only a single polymer, but also an alternating copolymer, a random copolymer, a block copolymer obtained by copolymerizing 50 mol% or less of another copolymerizable monomer. Including coalescence and graft copolymer. These polymers may be used alone or in combination of two or more.

  In addition to the hydrophobic monomer which is the main constituent, an amphiphilic polymer is used. Here, the “amphiphilic polymer” means a polymer having a hydrophobic part and / or a hydrophobic side chain and a hydrophilic part and / or a hydrophilic side chain in the main chain skeleton. As described above, the amphiphilic polymer is added to prevent water droplets attached to the polymer solution applied on the substrate from fusing together. The amphiphilic polymer that can be used is not particularly limited as long as it is a polymer having a hydrophobic part and / or a hydrophobic side chain and a hydrophilic part and / or a hydrophilic side chain in the main chain skeleton. For example, polyacrylamide as a main chain skeleton, and as a hydrophobic side chain, for example, a linear hydrocarbon group having 5 to 20 carbon atoms, a non-polar linear group such as a phenylene group, and the like An amphiphilic polymer having a hydrophilic group such as a hydroxy group, a carboxy group, an amino group, a carbonyl group, or a sulfo group as a hydrophilic side chain, such as the following formula:

(N-dodecylacrylamide) _n- (N-5-carboxypentylacrylamide) _m -block copolymer (n: m = 4: 1), polyethylene glycol having a hydrophobic part and a hydrophilic part A block copolymer with polypropylene glycol, or a polycondensation of dichlorodiphenylsulfone and sodium salt of bisphenol A, which is a hydrophobic part diphenylenedimethylmethylene group and a hydrophilic part in the main chain skeleton And polysulfone having a diphenylene sulfone group. These amphiphilic polymers may be used alone or in combination of two or more.

  The molecular weights of the hydrophobic polymer and the amphiphilic polymer are not particularly limited as long as they are dissolved in the hydrophobic organic solvent described later. For example, the weight average molecular weight (Mw) or the number average molecular weight (Mn) The lower limit is preferably 1,000, more preferably 5,000, still more preferably 10,000, and the upper limit is preferably 1,000,000, more preferably 500,000, still more preferably 100. , 000.

  Since the solvent for preparing the polymer solution needs to form water droplets on the polymer solution, a hydrophobic organic solvent is used. The hydrophobic organic solvent that can be used is not particularly limited as long as the hydrophobic polymer and the amphiphilic polymer described above are dissolved. For example, aromatic hydrocarbons such as benzene, toluene, and xylene; Halogenated hydrocarbons such as dichloromethane, chloroform, carbon tetrachloride, methylene chloride; esters such as ethyl acetate and butyl acetate; hydrophobic ketones such as methyl isobutyl ketone; ethers such as diethyl ether; carbon disulfide; Is mentioned. These hydrophobic organic solvents may be used alone or in combination of two or more.

  The polymer concentration of the total of the hydrophobic polymer and the amphiphilic polymer in the polymer solution (total polymer mass% with respect to the mass of the polymer solution) is appropriately adjusted according to the thickness, pore diameter, porosity of the honeycomb structure film, etc. However, the lower limit thereof is preferably 0.001% by mass, more preferably 0.005% by mass, still more preferably 0.01% by mass, and the upper limit thereof. Is preferably 10% by mass, more preferably 5% by mass, and still more preferably 1% by mass. When the polymer concentration is less than 0.001% by mass, the strength of the honeycomb structure film may be lowered, and the pore diameter and arrangement may be irregular. On the other hand, when the polymer concentration exceeds 10% by mass, pores may not be sufficiently formed.

  It is important that the amount of the amphiphilic polymer used is 1% by mass or more and 50% by mass or less with respect to the total mass of the hydrophobic polymer and the amphiphilic polymer. The lower limit of the amount of the amphiphilic polymer used is preferably 2% by mass, more preferably 4% by mass, and the upper limit thereof is preferably 40% by mass, more preferably 30% by mass. When the amount of the amphiphilic polymer used is less than 1% by mass, it is difficult to grow and transport water droplets on the surface of the polymer solution, and the pore size and arrangement may be irregular. On the other hand, when the amount of the amphiphilic polymer used exceeds 50% by mass, water droplets coalesce on the surface of the polymer solution, and pores may not be sufficiently formed.

  In order to apply the polymer solution onto the substrate, a normal coating technique may be used. The application amount of the polymer solution may be appropriately adjusted according to the size and thickness of the film, and is not particularly limited, but is, for example, in the range of 1 mL or more and 50 mL or less.

  The gas sprayed onto the surface of the polymer solution applied onto the substrate is not particularly limited as long as it does not inhibit the formation of the honeycomb structure film, and examples thereof include air, oxygen, carbon dioxide, nitrogen, and argon. . If a large amount of dust is present, film formation may be affected. Therefore, it is preferable to remove the dust by passing a gas through a filter, and the film formation is preferably performed in a clean room.

  When preparing a honeycomb structure film by self-organization, it is important to blow a gas having a relative humidity of 40% or more and 95% or less onto the surface of the polymer solution coated on the substrate at a substantially constant flow rate. . The lower limit of the relative humidity of the gas is preferably 30%, more preferably 35%, and the upper limit thereof is preferably 95%, more preferably 90%. If the relative humidity is less than 40%, sufficient water vapor does not condense on the surface of the polymer solution, and the desired pore size and porosity may not be obtained. On the other hand, if the relative humidity exceeds 95%, excessive water vapor condenses on the surface of the polymer solution, and vacancies may not be sufficiently formed. The gas flow rate may be appropriately adjusted according to the thickness, pore diameter, porosity, etc. of the honeycomb structure film to be formed, and is not particularly limited. For example, the lower limit thereof is preferably 0.01 m / s. More preferably 0.05 m / s, still more preferably 0.1 m / s, and the upper limit is preferably 1 m / s, more preferably 0.8 m / s, still more preferably 0.7 m / s. is there. When the flow rate is less than 0.01 m / s, it takes time to form a film, and the productivity may decrease. On the contrary, when the flow rate exceeds 1 m / s, the surface of the polymer solution may be disturbed, and the thickness of the honeycomb structure film may be non-uniform.

  The direction in which the gas is blown onto the surface of the polymer solution applied on the substrate may be any direction from a direction perpendicular to the substrate to a horizontal direction. It is preferably within a range of 30 ° or more and 60 ° or less with respect to a direction perpendicular to the substrate. In practice, a funnel sized to cover the entire substrate is held face down at a predetermined interval above the substrate coated with the polymer solution, and gas is supplied and sprayed from the capillary tube of the funnel. What should I do? In this case, the distance between the substrate and the funnel may be adjusted as appropriate according to the flow rate of the gas, and is not particularly limited, but is, for example, in the range of 2 cm to 10 cm.

  The lower limit of the porosity of the honeycomb structure film by self-organization is preferably 30%, more preferably 35%, still more preferably 40%, and the lower limit is preferably 80%, more preferably 75%. More preferably, it is 70%. Here, the “porosity” means the ratio of the total opening area of pores existing in a predetermined region of the honeycomb structure film. The porosity is a value obtained by observing the honeycomb structure film with an optical microscope and obtaining a region having a predetermined area randomly extracted from the actual use region excluding the peripheral portion. When the porosity is less than 30%, when used in a display device, the non-display portion increases, and the display quality may deteriorate. On the contrary, when the porosity exceeds 80%, the strength of the film may be lowered.

  The pore diameter of the honeycomb structure membrane by self-assembly is preferably 20 μm, more preferably 30 μm, and even more preferably 50 μm, and the upper limit is 100 μm, more preferably 90 μm, and even more preferably 80 μm. In addition, the variation coefficient of the pore diameter is preferably 30% or less, more preferably 25% or less, and further preferably 20% or less. Here, “pore diameter” means the diameter of a circle circumscribing the outline shape of the pores opened on the surface of the honeycomb structure membrane, and “pore diameter variation coefficient” means the relative standard deviation of the pore diameter distribution, that is, the pore diameter. It means a value expressed as a percentage obtained by dividing the standard deviation of the distribution by the average value of the pore diameters. The pore diameter and the variation coefficient of the pore diameter are values obtained by observing the honeycomb structure film with an optical microscope and obtaining 50 pores randomly extracted from the actual use area excluding the peripheral portion. When the pore diameter is less than 20 μm, the pore diameter and arrangement may be irregular. On the other hand, when the pore diameter exceeds 100 μm, the strength of the film is lowered, and when used in a display device, the display density is lowered and the display quality may be lowered. If the variation coefficient of the pore diameter exceeds 30%, the pore diameter and arrangement may be irregular, and the thickness of the honeycomb structure film may be nonuniform. The variation coefficient of the hole diameter is most desirably 0%, but it is very difficult to strictly control the film forming conditions in order to achieve the variation coefficient of 0%. Therefore, the lower limit of the variation coefficient of the pore diameter is preferably 5%, more preferably 3%, and further preferably 1%.

  In general, in order to reduce the pore size, for example, an organic solvent having a low boiling point is used as the hydrophobic organic solvent, the temperature of the substrate is increased, or the amount of the polymer solution applied on the substrate is reduced.

  The thickness of the honeycomb structure film varies depending on the pore diameter and is not particularly limited. For example, the lower limit thereof is preferably 10 μm, more preferably 15 μm, and further preferably 20 μm, and the upper limit thereof. Is preferably 200 μm, more preferably 180 μm, and even more preferably 150 μm. If the thickness is less than 10 μm, it becomes difficult for the electro-optic material to change the optical characteristics, and sufficient contrast may not be obtained, and handling may be difficult. Conversely, if the thickness exceeds 200 μm, a lightweight and flexible display device may not be provided. Note that the honeycomb structure film may be provided with a layer having no pores on the substrate side. In this case, the lower limit of the thickness of the layer having no voids is preferably 0 μm, more preferably 3 μm, still more preferably 5 μm, and the upper limit is preferably 180 μm, more preferably 150 μm, still more preferably. 120 μm. If the thickness of the layer having no pores exceeds 180 μm, the thickness of the honeycomb structure film increases, and the above-described disadvantage may occur. In addition, the effective voltage may be reduced at a portion where a voltage is applied for display, and sufficient contrast may not be obtained.

<Conductive film>
The conductive film is formed by forming a conductive layer on the base film, and functions as one electrode on the lower side of the honeycomb structure film and also supports the honeycomb structure film filled with the electro-optic material. In addition to functioning as the other electrode on the upper side of the honeycomb structure film, in some cases, it functions to seal pores of the honeycomb structure film filled with the electro-optic material.

  The conductive film preferably has transparency and conductivity. For example, a transparent conductive film formed by forming a conductive layer on the surface of a transparent plastic film is used. For example, the conductive film preferably has a transmittance of 80% or more and a surface electrical resistance of 1,000Ω or less. If the transmittance is less than 80%, the contrast may be lowered and the display may become unclear. Also, if the surface electrical resistance exceeds 1,000Ω, it becomes difficult for the electro-optic material to change the optical characteristics at the portion where the voltage is applied for display, and the response speed (display response) decreases. There are things to do.

  When displaying on one side of the display device, for example, the pores of the honeycomb structure film filled with the electro-optical material are sealed with a transparent conductive film or after being sealed with a transparent plastic film. If a conductive film is attached, the lower conductive film that supports the honeycomb structure film does not necessarily need to be transparent, and may be opaque. Conversely, if the lower conductive film that supports the honeycomb structure film is a transparent conductive film, the conductive film and / or plastic film that seals the pores of the honeycomb structure film filled with the electro-optic material is: It is not necessarily transparent and may be opaque.

  Examples of the material for the base film constituting the conductive film include acrylic resins, polyester resins, polyolefin resins, polycarbonate resins, and polyimide resins. Of these resins, polyester resins are preferable, and polyethylene terephthalate (PET) is particularly preferable.

  Examples of the material for the conductive layer formed on the base film include inorganic conductive materials such as indium tin oxide (ITO), zinc oxide, metal fine particles, and metal films, polyacetylene, polyaniline, polypyrrole, polyethylenedioxythiophene, Organic conductive materials such as polythiophene can be used.

  Examples of the method for forming the conductive layer on the base film include a dry coating method such as vacuum deposition and sputtering, and a wet coating method in which a dispersion or solution of a conductive substance is applied.

  The thickness of the conductive film is not particularly limited, but in the case of the lower conductive film that supports the honeycomb structure film, for example, the lower limit is preferably 20 μm, more preferably 50 μm, still more preferably 70 μm. In the case of the upper conductive film disposed on the honeycomb structure film or the conductive film sealing the pores of the honeycomb structure film, for example, the lower limit thereof is preferably 20 μm, more preferably 25 μm, still more preferably In the case of the conductive film on either side, the upper limit is preferably 200 μm, more preferably 180 μm, and still more preferably 150 μm. If the thickness is less than 20 μm, wrinkles are likely to occur and handling may be difficult. Conversely, if the thickness exceeds 200 μm, a lightweight and flexible display device may not be provided.

≪Manufacture of sheet for display device≫
The method for producing a display device sheet according to the present invention includes a step of applying a solution prepared by dissolving a hydrophobic polymer and an amphiphilic polymer in a hydrophobic organic solvent at a predetermined ratio on a substrate, and the step of applying the solution to the substrate. A gas having a predetermined relative humidity is sprayed onto the surface of the solution at a substantially constant flow rate to evaporate the organic solvent, condense water vapor on the surface of the solution, evaporate the generated water droplets, and self-assemble. A step of forming a honeycomb structure film according to the method, a step of filling each hole of the honeycomb structure film with an electro-optic material, and a step of sealing the pores of the honeycomb structure film filled with the electro-optic material It is characterized by doing.

  Since the steps up to the formation of the honeycomb structure film by self-organization are as described above, the description thereof is omitted here. The honeycomb structure film is formed on the substrate. For example, a conductive film may be used as the substrate, and may be formed on the conductive film from the beginning, or after being formed on another substrate, You may peel from a board | substrate and affix on an electroconductive film. In the case of forming on another substrate, the usable substrate is not particularly limited as long as it is a flat material having resistance to the above-described hydrophobic organic solvent and having a sufficiently smooth surface. However, examples of the material include glass, metal, and plastic.

  After forming on another board | substrate and peeling and sticking to an electroconductive film, you may provide the contact bonding layer on the surface of the said electroconductive film as needed. The material of the adhesive layer may be appropriately selected according to the material of the conductive film or the honeycomb structure film, and is not particularly limited. For example, polyester resin, acrylic resin, epoxy resin, urethane type Water-soluble or water-dispersible or emulsion-based resins such as resins, oxazoline-based resins, PVP-based resins, polyoxyalkylene-based resins, and cellulose-based resins can be used. Alternatively, an adhesive or a pressure-sensitive adhesive may be applied to the honeycomb structure film and then attached to the conductive film. The adhesive or pressure-sensitive adhesive may be appropriately selected according to the material of the conductive film or the honeycomb structure film, and is not particularly limited. For example, acrylic, vinyl-based agent, polycarbonate-based, urethane-based, Silicone and rubber adhesives and pressure-sensitive adhesives can be used. The formation of the adhesive layer and the application of the adhesive or the pressure-sensitive adhesive can be performed using a normal coating technique.

  Next, each of the pores of the honeycomb structured film formed on or attached to the conductive film by self-organization is filled with an electro-optic material. As the electro-optic material, for example, in the case of an electrophoretic material, the dispersion liquid for electrophoretic display manufactured as described above may be used. In the case of an electrostatic transfer material, the electrostatic transfer display manufactured as described above. A powder fluid may be used. The filling of the electro-optic material may be appropriately selected according to the type and is not particularly limited, and examples thereof include an inkjet technique and a method using a dispenser. The filling amount of the electro-optic material may be appropriately adjusted according to the size of the pores, and is not particularly limited. For example, in the case of an electrophoretic material, the dispersion liquid for electrophoretic display has pores. It is desirable to fill so that it is substantially complete.

  Finally, the display device is obtained by sealing the pores of the honeycomb structure film filled with the electro-optic material. In order to seal the pores, a plastic film may be stuck, or the conductive film may be stuck so that the conductive layer faces the pores as described above. Examples of the plastic film that can be used include a film made of the same material as the base film constituting the conductive film. Examples of the conductive film that can be used include the above-described conductive films listed as the lower conductive film that supports the honeycomb structure film.

  The thickness of the plastic film that seals the pores of the honeycomb structure film is not particularly limited. For example, the lower limit thereof is preferably 20 μm, more preferably 25 μm, and further preferably 30 μm. The upper limit is preferably 200 μm, more preferably 180 μm, and still more preferably 150 μm. If the thickness is less than 20 μm, wrinkles are likely to occur and handling may be difficult. Conversely, if the thickness exceeds 200 μm, a lightweight and flexible display device may not be provided. The thickness of the conductive film that seals the pores of the honeycomb structure film is as described above.

  When sealing the pores of the honeycomb structure film with a plastic film or a conductive film, for example, an adhesive layer may be provided in the same manner as when the honeycomb structure film is attached to the conductive film. Alternatively, the conductive film may be attached after applying an adhesive or a pressure-sensitive adhesive to the honeycomb structure film.

  Thus, the display device sheet of the present invention is obtained. The sheet for a display device of the present invention basically has a honeycomb structure film formed by self-organization on a conductive film, and the pores of the honeycomb structure film filled with an electro-optic material are sealed with a plastic film. Although it means a stopped laminated sheet, in some cases, it may mean a laminated sheet sealed with a conductive film instead of the plastic film.

≪Display device≫
The display device of the present invention is a display device in which an electro-optic material is held between opposed electrodes, and a conductive film to be the other electrode is disposed on the honeycomb structure film in the display device sheet. It is characterized by being.

  In the display device of the present invention, the distance between both conductive films, that is, the distance between the opposing electrodes varies depending on the thickness of the honeycomb structure film by self-organization, and is not particularly limited. The lower limit is preferably 20 μm, more preferably 30 μm, still more preferably 50 μm, and the upper limit is preferably 200 μm, more preferably 150 μm, and still more preferably 100 μm. When the distance between the opposing electrodes is less than 20 μm, a sufficient display density cannot be obtained in the display portion, and it may be impossible to clearly distinguish from other non-display portions. On the other hand, if the distance between the opposing electrodes exceeds 200 μm, the electro-optical material may not exhibit sufficient changes in optical characteristics, and display characteristics such as contrast may be deteriorated or display drive voltage may be increased. There is.

  The display device of the present invention is the same as a conventionally known display device except for the data display unit. Therefore, portions other than the data display unit, such as a drive circuit and a power supply circuit, may be configured in the same manner as a conventionally known display device. For example, if a conductive film that seals the pores of the honeycomb structure film is provided with a driver layer made of a thin film transistor using amorphous silicon or polysilicon or an organic transistor using organic molecules, the display can be controlled. Can do. Alternatively, rewriting may be performed by an external device without providing a driver layer. The means for controlling the display may be appropriately selected according to the use of the display device, and is not particularly limited. The obtained display device may incorporate other components such as a drive circuit and a power supply circuit as necessary. In the present invention, a device incorporating such a drive circuit or a power supply circuit may be referred to as a display device. In the present invention, a drive circuit, a power supply circuit, and the like may be included in an external circuit, and only the data display unit may be referred to as a display device.

<Manufacture of display devices>
In order to manufacture the display device of the present invention, for example, a sheet for a display device is cut into a predetermined size, and another conductive film is used, for example, using an adhesive or an adhesive, or by a lamination technique or the like. Just stick. At this time, if the conductive layer of another conductive film is opposed to the honeycomb structure film filled with the electro-optic material, the conductive layer of the other conductive film functions as the other electrode in the display device. As described above, if a driver layer including a thin film transistor using amorphous silicon or polysilicon or an organic transistor using organic molecules is provided on another conductive film, display can be controlled. Alternatively, rewriting may be performed by an external device without providing a driver layer. The means for controlling the display may be appropriately selected according to the use of the display device, and is not particularly limited. The obtained display device may incorporate other components such as a drive circuit and a power supply circuit as necessary. In the case where another conductive film is attached to the display device sheet using an adhesive or an adhesive, examples of usable adhesives and adhesives include a honeycomb structure film on the lower conductive film. Examples of the adhesives and pressure-sensitive adhesives listed above are the adhesives and pressure-sensitive adhesives used for sticking. Moreover, when laminating another conductive film on the sheet for display device, conventionally known techniques can be appropriately selected and used for the laminating method and conditions.

  Thus, the display device of the present invention is obtained. The display device of the present invention may be called with a specific name depending on the type of electro-optic material used for the display device. Specifically, for example, an electrophoretic display device is used when an electrophoretic material is used, and an electrostatic transfer display device is used when an electrostatic transfer material is used.

<Operation principle of display device>
The display device of the present invention displays character data and image data based on the following operation principle, for example.

  In the case of a one-particle electrophoretic display device, for example, if the pigment particles constituting the electrophoretic particles are white pigment particles and the dispersion medium is colored with a blue dye, the initial display is light blue. However, when a voltage is applied between the opposing electrodes, the electrophoretic particles move in one electrode direction to display white or blue, and when the voltage polarity is reversed, the electrophoretic particles move in the other electrode direction. Therefore, the white display or the blue display is inverted to become a blue display or a white display. When the polarity is reversed again and the voltage is applied for a very short time, the display returns to light blue. Alternatively, if the blue display or the white display is left without applying a voltage, the display can be maintained and recorded for a long time.

  In the case of a two-particle electrophoretic display device or electrostatic transfer display device, for example, the pigment particles constituting the electrophoretic particles or electrostatic transfer particles may be a combination of white pigment particles and black pigment particles. For example, the initial display is gray, but when a voltage is applied between the opposing electrodes, one electrophoretic particle or electrostatic transfer particle moves in the direction of one electrode, and the other electrophoretic particle or electrostatic transfer particle. Moves in the direction of the other electrode and becomes white display or black display, and when the polarity of the voltage is reversed, these electrophoretic particles or electrostatic transfer particles move in the direction of the electrodes opposite to each other. The black display is reversed to display black or white. When the polarity is reversed again and the voltage is applied for a very short time, the display returns to gray. Alternatively, if the black display or the white display is left without applying a voltage, the display can be maintained and recorded for a long period of time.

  In any display device, in order to display or record character data, image data, or the like, for example, an electrode located on the back side of the device is set to a predetermined reference potential (for example, 0 V), and a driver is connected to the electrode located on the front side of the device. A layer may be provided so as to have a positive potential or a negative potential with respect to the reference potential corresponding to the color of the data (in this case, blue, black, or white) at each position on the display surface.

<Use of display device>
The display device of the present invention is used in various electronic devices as data display means, for example. The electronic device of the present invention is an electronic device provided with data display means, and the data means is the display device of the present invention. Here, “data display means” means means for displaying character data, image data, and the like. The electronic device of the present invention is the same as a conventionally known electronic device except that the data means is the display device of the present invention. Therefore, the portion other than the data display means may be configured in the same manner as a conventionally known electronic device. That is, the electronic device of the present invention can be obtained by replacing the data display means in a conventionally known electronic device with the display device of the present invention.

  The electronic apparatus to which the display device of the present invention can be applied is not particularly limited as long as it has data display means. For example, a personal computer, a workstation, a word processor, an IC card, an IC tag, an electronic notebook, Electronic dictionary, IC recorder, electronic book, electronic paper, electronic notebook, calculator, electronic newspaper, electronic whiteboard, information board, advertising board, various displays, TV, DVD player, digital still camera, viewfinder type or monitor direct view type Examples include a video camera, a car navigation system, a mobile phone, a video phone, a pager, a mobile terminal, a POS terminal, and various devices including a touch panel. Among these electronic devices, in order to take advantage of the advantages that the display device of the present invention is lightweight and flexible and can be provided in large quantities at a low price, an IC card, an IC tag, an electronic book, electronic paper, electronic Notebooks, electronic newspapers, electronic whiteboards, information boards, advertising boards, mobile phones, pagers, mobile terminals and the like are particularly suitable.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, but may be appropriately modified within a range that can meet the purpose described above and below. It is also possible to implement, and they are all included in the technical scope of the present invention.

  Measurement methods and evaluation methods used in the following examples and comparative examples are shown below.

<Porosity>
The honeycomb structure film is observed with an optical microscope (magnification 100 times), and the area (450 μm × 800 μm) randomly extracted from the actual use area excluding the peripheral part is the total opening area of the pores existing in this area Is a value expressed as a percentage (%) with respect to the area of this region.

<Pore diameter>
Observe the honeycomb structure film with an optical microscope (100x magnification) and measure the diameter of the circle circumscribing the outline shape of each hole for 50 holes randomly extracted from the actual use area excluding the peripheral edge. The average value of the measured values obtained.

<Coefficient of variation in pore diameter>
The honeycomb structure film was observed with an optical microscope (magnification 100 times), and for 50 holes randomly extracted from the actual use area excluding the peripheral portion, the hole diameter of each hole was obtained, statistical processing was performed, This is a value expressed as a percentage (%) by dividing the standard deviation of the pore size distribution by the average value of the pore sizes.

<Display responsiveness>
Display response (time required for reverse display (white display)) after switching the polarity of the voltage after applying a DC voltage of 15 V between the opposing electrodes of the display device to display in blue or black Evaluated by criteria. Observation was performed using the naked eye and an optical microscope. The white display is derived from the color of the electrophoretic particles or the pigment particles constituting one of the electrostatic transfer particles, the blue display is derived from the color of the dye coloring the dispersion medium, and the black display is the other electrostatic transfer particle. Derived from the color of the pigment particles constituting Hereinafter, the same applies to other evaluations.
○: Less than 2 seconds Δ: 2 seconds or more, less than 4 seconds ×: 4 seconds or more

<Display stability>
A white voltage was displayed by applying a DC voltage of 15 V between the opposing electrodes of the display device, and then the display stability (the time during which the white display was maintained) when the voltage was turned off was evaluated according to the following criteria. Observation was performed using the naked eye and an optical microscope.
○: (24 × 7) hours or more Δ: 24 hours or more, less than (24 × 7) hours ×: less than 24 hours.

<Contrast>
A 15 V DC voltage is applied between the opposing electrodes of the display device to display white, blue, or black, and the reflectance of each display is determined by the Macbeth spectrophotometer (product name: Spectro Eye, manufactured by Gretag Macbeth) ) And the contrast was determined by the following equation.
Contrast = reflectance of white display / reflectance of blue display or black display.

  In addition, the reflectance of white display, blue display, or black display is measured separately by switching the polarity and applying a voltage, and each reflectance is an average value measured on one side of the display device.

Example 1
<Manufacture of dispersion for electrophoretic display>
After mixing and dissolving 0.5 g of aminopropyltrimethoxysilane (product name KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.) in 90 g of methanol, 0.5 g of 2.5% aqueous ammonia was added.

  To this solution, 50 g of titanium oxide (product name: Taipei CR-97, manufactured by Ishihara Sangyo Co., Ltd .; average particle size: 0.25 μm) was added, and ultrasonic dispersion treatment was performed at 50 ° C. for 60 minutes with stirring. Next, 1.5 g of isopropyl isostearoyl titanate (product name: Plenact KR-TTS, manufactured by Ajinomoto Co., Inc.) was added, and ultrasonic dispersion treatment was further performed for 60 minutes. The dispersion was centrifuged to collect titanium oxide and dried at 120 ° C. to obtain surface-treated titanium oxide. The surface-treated titanium oxide was used as white electrophoretic particles, and the average particle size was 0.32 μm in volume average particle size.

  14 g of surface-treated titanium oxide was added to 130 g of isoparaffin (product name Isopar M, manufactured by Exxon Mobil), and ultrasonic dispersion treatment was performed at 50 ° C. for 30 minutes. Thereafter, 2 g of a blue dye (product name: Plast Blue 8510, manufactured by Arimoto Chemical Industry Co., Ltd.) was mixed and dissolved to obtain a dispersion for electrophoretic display. When the zeta potential of this dispersion was measured with a zeta potential measuring device (product name ESA-9800, manufactured by Matec Applied Sciences), the absolute value was 74 mV.

<Formation of honeycomb structure film by self-organization>
5 g of poly (ε-caprolactone) having a mass average molecular weight of 70,000 and (N-dodecylacrylamide) _n- (N-5-carboxypentylacrylamide) _m -block copolymer (n: m) having a mass average molecular weight of about 200,000 = 4: 1) 15 mL of a polymer solution prepared by dissolving 0.5 g in 1 L of chloroform was applied to a glass petri dish having a diameter of 90 mm, and air with a temperature of 22.8 ° C. and a relative humidity of 53% was applied to the surface at a substantially constant flow rate. Spraying was carried out at 0.5 m / s to evaporate chloroform, to condense water vapor on the surface of the polymer solution, to evaporate the generated water droplets, and to form a film by self-assembly.

  When the obtained film was observed with an optical microscope (magnification 100 times), it was confirmed that it was a honeycomb structure film in which the through-holes in which the upper and lower vacancies were in an open state were substantially continuously arranged in a single layer. It was done. This honeycomb structure film had a thickness of 32 μm, a porosity of 78%, a pore diameter of 30 μm, and a pore diameter variation coefficient of 18%. The results are shown in Table 1.

<Manufacture of display devices>
The honeycomb structure film obtained above was peeled off from the glass petri dish in ethanol, and was stuck on the ITO electrode of a PET film with ITO electrode (product name Tretec TN02, manufactured by Toray Industries, Inc .; thickness 125 μm). An acrylic pressure-sensitive adhesive (product name: Acriset P5-4516, manufactured by Nippon Shokubai Co., Ltd.) was roll-coated on the upper surface of the pores of the honeycomb structure film. Next, the electrophoretic display dispersion obtained above was filled into each pore of the honeycomb structure film by an ink jet technique. In order to seal the pores of the honeycomb structure film, a PET film with an ITO electrode (product name Tretec TN02, manufactured by Toray Industries, Inc .; thickness 125 μm) is overlaid so that the ITO electrode faces the pores. A display device was obtained by pasting with the applied acrylic pressure-sensitive adhesive.

  The electrophoretic display device thus obtained was evaluated for display response, display stability, and contrast. The results are shown in Table 1.

<< Example 2 >>
<Manufacture of powder fluid for electrostatic transfer display>
20 g of titanium oxide treated with γ-methacryloxypropyltrimethoxysilane, 5 g of charge control agent (product name Bontron E-89, manufactured by Orient Chemical Industries), 1 g of polymerization initiator (azobisbutyronitrile), methacryl After mixing and dispersing 75 g of methyl acid, suspension polymerization was performed at 75 ° C. for 5 hours. The reaction solution was centrifuged to collect titanium oxide and dried at 80 ° C. to obtain titanium oxide coated with an acrylic polymer. Titanium oxide coated with this acrylic polymer was used as white electrostatic transfer particles, and the average particle size was 3.1 μm in terms of volume average particle size.

  Subsequently, using a hybridizer (product name NHS-0 type, manufactured by Nara Machinery Co., Ltd.), 3% by mass of an external additive (product name: Aerosil R972, Nippon Aerosil Co., Ltd.) was added and treated at 3,800 rpm for 5 minutes to immobilize the external additive on the surface of the white electrostatic transfer particles to obtain a white powder fluid.

  On the other hand, 5 g of carbon black (product name # 44, manufactured by Mitsubishi Chemical Corporation), 5 g of charge control agent (product name: Bontron N-07, manufactured by Orient Chemical Co., Ltd.), polymerization initiator (azobisbutyronitrile) 1 g and 75 g of styrene were mixed and dispersed, and then suspension polymerization was performed at 75 ° C. for 5 hours. The reaction solution was centrifuged to collect carbon black and dried at 80 ° C. to obtain carbon black coated with a styrene polymer. Carbon black coated with this styrenic polymer was used as black electrostatic transfer particles, and the average particle size was 3.5 μm in terms of volume average particle size.

  Subsequently, using a hybridizer (product name NHS-0 type, manufactured by Nara Machinery Co., Ltd.), 3% by mass of an external additive (product name: Aerosil H2000, Nippon Aerosil Co., Ltd.) was added and treated at 3,800 rpm for 5 minutes to immobilize the external additive on the surface of the black electrostatic transfer particles to obtain a black powder fluid.

  The charge amount of these powder fluids is measured using a blow-off powder charge amount measuring device (product name TB-200, manufactured by Toshiba Chemical Corporation) using iron powder (product name DSP-128, manufactured by Dowa Iron Powder Co., Ltd.). The white powder fluid was −78 μC / g and the black powder fluid was +56 μC / g.

  The white powder fluid and the black powder fluid were sufficiently mixed at a mass ratio of 1.5: 1 to obtain a powder fluid for electrostatic transfer display.

<Formation of honeycomb structure film by self-organization>
A honeycomb structure film was formed in the same manner as in Example 1 except that 5 g of polysulfone having a number average molecular weight of 26,000 was used instead of 5 g of poly (ε-caprolactone) having a mass average molecular weight of 70,000. This honeycomb structure film had a thickness of 80 μm, a porosity of 45%, a pore diameter of 100 μm, and a pore diameter variation coefficient of 26%. The results are shown in Table 1.

<Manufacture of display device sheet and display device>
The honeycomb structure film obtained above was peeled off from the glass petri dish in ethanol, and was stuck on the ITO electrode of a PET film with ITO electrode (product name Tretec TN02, manufactured by Toray Industries, Inc .; thickness 125 μm). Subsequently, each of the pores of the honeycomb structure film was filled with the electrostatic fluid display powder fluid obtained above. After standing for several hours, the powder fluid adhering to the upper surface of the pores of the honeycomb structure film is removed with an adhesive roll, and an acrylic adhesive (product name: Acryset P5 is applied to the upper surface of the pores of the honeycomb structure film. -4516, manufactured by Nippon Shokubai Co., Ltd.). In order to seal the pores of the honeycomb structure film, a PET film with an ITO electrode (product name Tretec TN02, manufactured by Toray Industries, Inc .; thickness: 125 μm) is stacked so that the ITO electrode faces the pores. A display device was obtained by pasting and pasting with the acrylic adhesive applied.

  The electrophoretic display device thus obtained was evaluated for display response, display stability, and contrast. The results are shown in Table 1.

Example 3
A honeycomb structure film was formed in the same manner as in Example 1 except that the amount of the amphiphilic polymer used was changed from 0.5 g to 0.25 g. The thickness was 55 μm, the porosity was 61%, the pore diameter was 50 μm, and the variation coefficient of the pore diameter was 17%. The results are shown in Table 1.

  A display device sheet and an electrophoretic display device were produced in the same manner as in Example 1 except that the obtained honeycomb structure film was used. The electrophoretic display device was evaluated for display response, display stability, and contrast. The results are shown in Table 1.

Example 4
In the same manner as in Example 1, except that air having a temperature of 22.8 ° C. and a relative humidity of 70% was blown instead of blowing air having a temperature of 22.8 ° C. and a relative humidity of 53% to the surface of the polymer solution, A structural film was formed. This honeycomb structure film had a thickness of 45 μm, a porosity of 80%, a pore diameter of 25 μm, and a pore diameter variation coefficient of 11%. The results are shown in Table 1.

  A display device sheet and an electrophoretic display device were produced in the same manner as in Example 1 except that the obtained honeycomb structure film was used. The electrophoretic display device was evaluated for display response, display stability, and contrast. The results are shown in Table 1.

≪Comparative example 1≫
Except for not using an amphiphilic polymer, an attempt was made to form a honeycomb structure film in the same manner as in Example 1. Although a film was obtained, a large number of pores were arranged continuously and regularly. No honeycomb structure was formed.

«Comparative example 2»
A honeycomb structure film was formed in the same manner as in Example 1 except that the amount of the amphiphilic polymer used was changed from 0.5 g to 0.001 g. The thickness was 4 to 5 μm, the porosity was 70%, the pore diameter was 2 to 15 μm, and the variation coefficient of the pore diameter was 120%. The results are shown in Table 1.

  A display device sheet and an electrophoretic display device were produced in the same manner as in Example 1 except that the obtained honeycomb structure film was used. The electrophoretic display device was evaluated for display response, display stability, and contrast. The results are shown in Table 1.

«Comparative Example 3»
In the same manner as in Example 1, except that air having a temperature of 22.8 ° C. and a relative humidity of 53% was sprayed on the surface of the polymer solution, instead of blowing air having a temperature of 22.8 ° C. and a relative humidity of 10%, An attempt was made to form a structural film, but although a film was obtained, a honeycomb structure in which a large number of pores were arranged continuously and regularly was not formed.

  As is clear from Table 1, in Examples 1 to 4, the usage amount of the amphiphilic polymer and the relative humidity of the gas sprayed onto the surface of the polymer solution are both within a predetermined range. Although it does not require complicated manufacturing equipment and can be manufactured very easily and inexpensively, its porosity, hole diameter, and coefficient of variation in hole diameter are within the appropriate range for a display device using an electro-optic material. In spite of being lightweight and flexible, the display device manufactured by using the display showed excellent display response and display stability and high contrast. On the other hand, since Comparative Example 1 did not use an amphiphilic polymer, a honeycomb structure film could not be obtained, and Comparative Example 2 had a honeycomb structure because the amount of amphiphilic polymer used was outside the predetermined range. Membranes have non-uniform pore diameters and a high coefficient of variation in pore diameter, and display devices manufactured using them have a large number of unevenness, low contrast, and display response and stability. In Comparative Example 3, the honeycomb structure film was not obtained because the relative humidity of the gas sprayed onto the surface of the polymer solution was outside the predetermined range. As described above, according to the present invention, it is possible to provide a lightweight and flexible display device having excellent display characteristics.

  The present invention makes it possible to provide a large amount of lightweight and flexible display devices at a low price, and thus makes a great contribution in various fields related to electronic paper.

The partial cross section perspective view which shows an example of the sheet | seat for display apparatuses of this invention.

Explanation of symbols

10 Sheet for Display Device 20 Conductive Film 22 Base Film 24 Conductive Layer (Electrode)
30, 32, 34, 36, 38 Electro-optic material (dispersion liquid for electrophoretic display and / or powder fluid for electrostatic transfer display)
40 Self-organized honeycomb structure film 50, 52, 54, 56, 58

Claims (6)

  Electrostatic transfer comprising a dispersion liquid for electrophoretic display containing at least one type of electrophoretic particles in a dispersion medium and / or at least two types of electrostatic transfer particles on a conductive film functioning as one electrode. A sheet for a display device that holds a powder fluid for display, wherein the electrophoretic display dispersion liquid and / or the electrostatic fluid display powder fluid is disposed on the conductive film. A sheet for a display device, wherein each of the pores of the honeycomb structure film formed by filling is filled and sealed.   The sheet for a display device according to claim 1, wherein the honeycomb structure film has a porosity of 30% to 80%, a pore diameter of 20 µm to 100 µm, and a pore diameter variation coefficient of 30% or less.   The display device sheet according to claim 1, wherein the pores of the honeycomb structure film are substantially arranged in a single layer.   It is a method of manufacturing the sheet | seat for display apparatuses of any one of Claims 1-3, Comprising: The usage-amount of the said amphiphilic polymer is a hydrophobic polymer and an amphiphilic polymer, and the said hydrophobic polymer is used. A step of applying a solution dissolved in a hydrophobic organic solvent on the substrate so that the total mass with the amphiphilic polymer is 1% by mass or more and 50% by mass or less; Further, a gas having a relative humidity of 40% or more and 95% or less is sprayed on the surface of the solution at a substantially constant flow rate to evaporate the organic solvent and to condense water vapor on the surface of the solution. A step of evaporating to form a honeycomb structured film by self-organization; a dispersion for electrophoretic display containing at least one kind of electrophoretic particles in a dispersion medium in each pore of the honeycomb structured film; and / or Or small A step of filling a powder fluid for electrostatic transfer display comprising at least two kinds of electrostatic transfer particles, and the honeycomb structure filled with the dispersion liquid for electrophoretic display and / or the powder fluid for electrostatic transfer display And a step of sealing the pores of the film.   The manufacturing method according to claim 4, wherein a flow rate of the gas is 0.01 m / s or more and 1 m / s or less.   An electrophoretic display dispersion liquid containing at least one type of electrophoretic particles in a dispersion medium and / or a powder fluid for electrostatic transfer display composed of at least two types of electrostatic transfer particles are held between opposing electrodes. It is a display apparatus formed, Comprising: The electroconductive film used as the other electrode is arrange | positioned on the said honeycomb structure film | membrane in the sheet | seat for display apparatuses of any one of Claims 1-3, It is characterized by the above-mentioned. Display device.

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