Nippon Shokubai Co., Ltd.

Seiko Epson Corporation

Tomoyuki Kuwamoto

Hitoshi Yamamoto

Harunobu Komatsu

Mitsuo Kushino

Teruki Matsushita

Akira Matsumoto

Takeo Kawase

Hayato Ikeda

Tatsuhito Matsuda

Akio Naka

Hironobu Hashimoto

Hirokazu Niwa

Hideo Asano

Jiro Iriguchi

Junichi Chosa

Hiroyasu Watabe

Yoshiyuki Shiotani

Akira Masumoto

Teruki Matsuhita

Tsuyoshi Yamashita

An electrophoretic display sheet comprising a display layer, a first electrode, and second electrodes. The display layer has a plurality of reservoir portions filled with a dispersion liquid containing particles. Each of the plurality of reservoir portions has predetermined positions. When an electric field having a direction is generated by applying a voltage to between the first electrode and the second electrodes, the particles are locally gathered to the predetermined positions of each of the plurality of reservoir portions so as to make rows of the particles along the direction of the electric field in the dispersion liquid. The electrophoretic display sheet is capable of exhibiting both superior responsiveness (responsibility) and superior color display performance with high contrast in changing a display color.

Electrophoretic display sheet, electrophoretic display apparatus, and electronic device

The coating composition for electrophoretic display devices according to the present invention contains microcapsules for electrophoretic display devices and a binder resin, wherein the binder resin has a glass transition temperature (Tg) in a range of from &#x2212;85&#xb0; C. to &#x2212;10&#xb0; C. as calculated by FOX formula and has a residual monomer concentration of 500 ppm or lower in a solid content thereof. The sheet for electrophoretic display devices according to the present invention has a microcapsule layer formed from the above-described coating composition for electrophoretic display devices on a base material sheet. The sheet for electrophoretic display devices according to the present invention can be used, as its applications, for electrophoretic display devices using the sheets, and electronic equipments using the electrophoretic display devices.

Coating composition for electrophoretic display devices, sheet for electrophoretic display devices, process for its production, and its applications

A method of manufacturing an electrophoretic display device is provided. The method comprises: preparing a plate-shaped first electrode provided on a first base portion, and the first electrode having a surface; preparing plate-shaped second electrodes provided on a second base portion; forming a first binder layer on the surface of the first electrode; supplying a plurality of microcapsules on the first binder layer, the plurality of microcapsules each having an internal space, the internal space filled with an electrophoretic dispersion liquid, the electrophoretic dispersion liquid containing electrophoretic particles having different colors, and the plurality of microcapsules including properly-sized microcapsules and improperly-sized microcapsules; fixing the properly-sized microcapsules to the surface of the first electrode through the first binder layer to obtain an electrophoretic display sheet; removing the improperly-sized microcapsules which are not brought into contact with the first binder layer from the electrophoretic display sheet; forming a second binder layer on the first binder layer so as to cover the properly-sized microcapsules; and providing the second electrodes on the second binder layer to obtain the electrophoretic display device. The method is capable of efficiently manufacturing the electrophoretic display device having high display performance by arranging microcapsules on electrodes so that the microcapsules are not overlapped with each other. Further, an electrophoretic display device and an electronic device are also provided.

Method of manufacturing electrophoretic display device, electrophoretic display device and electronic device

The microcapsules for electrophoretic display devices according to the present invention each enclose a dispersion containing electrophoretic particles and a solvent in a shell having an inner shell made of a mercapto group-containing amino resin and an outer shell made of an epoxy resin. Alternatively, the microcapsules for electrophoretic display devices according to the present invention each have a capsule strength of 0.6 MPa or higher. These microcapsules are produced by dispersing a dispersion containing electrophoretic particles and a solvent as a core substance in a water-based medium, and subsequently forming at least one shell on the surface of the core substance. These microcapsules can be used, as their applications, for sheets for electrophoretic display devices, electrophoretic display devices using the sheets, and electronic equipments using the electrophoretic display devices.

Microcapsules for electrophoretic display devices, and processes for their production, and their applications

A display device having a display surface, comprises: a contact particle-containing layer including a wall portion with an inner surface for defining a space, contact particles electrically charged and provided within the space in a contact state that the contact particles are in contact with the inner surface of the wall portion, the contact particles having a hue, and a scattering medium for scattering light or a colored medium having a different hue from the hue of the contact particles which is provided within the space; and a pair of electrodes that, when applied with an electrical voltage, generate electrical fields to act on the contact particles, wherein the display device is configured so that when the electrical voltage is applied to between the pair of electrodes, the contact particles are moved along the inner surface of the wall portion while maintaining the contact state.

Display device, method of manufacturing display device and electronic apparatus

The invention provides a retardation film, composed primarily of an acrylic polymer, with transparency, heat resistance, and large retardation. The retardation film of the present invention is composed primarily of an acrylic polymer. The film has an in-plane retardation of from 130 nm to 500 nm, inclusive, per 100 &#x3bc;m thickness at a wavelength of 589 nm. The film has a total light transmittance of not less than 85%. The retardation film has a glass transition temperature of preferably from 110&#xb0; C. to 200&#xb0; C., inclusive. The acrylic polymer, which is the primary component, preferably has a lactone ring structure.

Retardation film

An electrophoretic sheet includes a substrate having one surface and the other surface, a microcapsule-containing layer comprised of a plurality of microcapsules, the microcapsule-containing layer provided on the other surface of the substrate, each of the plurality of microcapsules having a capsule body and an electrophoretic dispersion liquid contained in the capsule body, the electrophoretic dispersion liquid containing a plurality of electrophoretic particles of at least one color, and the capsule body having an inner circumferential surface and an outer circumferential surface, and at least one colored part provided on the external side of the inner circumferential surface of the capsule body of each of the plurality of microcapsules, and wherein each colored part has a color complementary to the color of the plurality of electrophoretic particles. By using the electrophoretic sheet mentioned above, it is possible to provide the increased whiteness in display of the electrophoretic particles. An electrophoresis apparatus provided with such an electrophoretic sheet is also provided. By using the electrophoresis apparatus, it is possible to provide a superior contrast ratio. It is also possible to obtain high reliability. A Method for manufacturing such an electrophoresis apparatus is also provided. An electronic device provided with such an electrophoresis apparatus is also provided.

Electrophoretic sheet, electrophoresis apparatus, method for manufacturing an electrophoresis apparatus and electronic device

An electrophoretic display device is provided. The electrophoretic display device comprises a first electrode provided on a surface of a first base member; second electrodes provided on a surface of a second base member so that the second electrodes are placed in a facing relationship with the first electrode; and a plurality of microcapsules provided between the first electrode and the second electrodes, the plurality of microcapsules each having an internal space filled with an electrophoretic dispersion liquid, and the electrophoretic dispersion liquid containing electrophoretic particles. The electrophoretic display device is configured so that spaces are formed between the adjacent microcapsules and between the first electrode and the second electrodes. The electrophoretic display device can exhibit superior display performance and can be driven with a low voltage and reduced electricity consumption. A method of manufacturing an electrophoretic display device and an electronic device are also provided.

Electrophoretic display device, method of manufacturing electrophoretic display device, and electronic device

A display device comprises a microcapsule-containing layer including a plurality of microcapsules. A variation of the outer diameters of the microcapsules can be defined by an average value and a CV value. Each of the microcapsules is comprised of: a shell having an inner surface; contact particles electrically charged and provided within the shell in an contact state that the contact particles are in contact with the inner surface of the shell; and a scattering body for scattering light; or a colored particles having a different hue from the hue of the contact particles. The display device further comprises a pair of electrodes that when an electrical voltage is applied to between the pair of electrodes, electrical fields to act on the contact particles are generated. The average value of the outer diameters of the microcapsules is in the range of 20 to 60 &#x3bc;m, and the CV value of the outer diameters of the microcapsules is 20% or less. In a case where the electrical voltage is applied to between the pair of electrodes, the contact particles are moved along the inner surface of the shell while maintaining the contact state with the inner surface of the shell.

An electrophoretic display sheet capable of increasing pressure resistance and bleed resistance of microcapsules and constructing an electrophoretic display device stably operable for a long period of time, a highly reliable electrophoretic display device and a highly reliable electronic apparatus are provided. The electrophoretic display sheet includes a base substrate having one major surface, and a microcapsule-containing layer provided on the side of the one major surface of the base substrate and having one major surface, the microcapsule-containing layer including a plurality of microcapsules, each of the microcapsules having a shell and an electrophoretic dispersion liquid containing at least one kind of electrophoretic particles and encapsulated into the shell, wherein the microcapsules exist in a generally spherical shape within the microcapsule-containing layer.

Electrophoretic display sheet, electrophoretic display device and electronic apparatus

A display device capable of easily and reliably obtaining an intermediate tone and reliably maintaining individual colors including the intermediate tone even at stoppage of application of an electrical voltage, a manufacturing method of a display device capable of easily and reliably manufacturing the display device, and an electronic apparatus provided with the display device are provided. The display device has a display surface. The display device includes an adsorption particle-containing layer including a wall portion with an inner surface for defining a space, a plurality of electrically charged adsorption particles provided within the space in an adsorbed state that they are adsorbed to the inner surface of the wall portion, and a substantially transparent medium provided within the space, and a pair of electrodes that, when applied with an electrical voltage, generate electrical fields to act on the adsorption particles, wherein in the case where the electrical voltage is applied to between the electrodes, the adsorption particles are moved along the inner surface of the wall portion while maintaining the adsorbed state.

The preservation method of microcapsules for electrophoretic display devices according to the present invention includes preserving microcapsules for electrophoretic display devices in a water-based medium having an electric conductivity of 500 &#x3bc;S/cm or lower. The preservation under such conditions makes it possible to preserve microcapsules for electrophoretic display devices over a long period of time without deteriorating their electrophoretic properties. The microcapsules for electrophoretic display devices, which have been preserved by the preservation method of the present invention, can be used, as its applications, for sheets for electrophoretic display devices and electrophoretic display devices using the sheets.

Preservation method of microcapsules for electrophoretic display devices and its applications

The present invention provides: a fine particles-dispersed composition that has extremely good dispersibility even if a polyamidic acid is contained in the composition; and a production process for such a composition. The polyamidic acid-containing and fine particles-dispersed composition comprises fine particles and a polar solvent solution, wherein the fine particles are dispersed in the polar solvent solution using an organic polymer as a dispersant, and this composition further comprises a polyamidic acid.

Polyamidic acid-containing and fine particles-dispersed composition and production process therefor

A process for preparing an aqueous resin dispersion includes the steps of copolymerizing a polymeric monomer whose ratio of (meth) acrolein to a total amount of the (meth) acrolein and a vinyl monomer is in the range from 10 weight % to 80 weight % in an organic solvent to obtain a copolymer solution, dispersing the obtained copolymer solution in an aqueous medium and removing an unreacted (meth) acrolein. Since the above process can extremely reduce contents of the unreacted (meth) acrolein and of an oligomer whose number-average molecular weight is less than 1000, an aqueous resin dispersion where problems of a pungent smell, toxicological properties, etc. due to the (meth) acrolein and the oligomer are eliminated can be provided.

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Nara, Japan

Tomoyuki Kuwamoto