Patents by Inventor Kenta Tojo
Kenta Tojo has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20230287272Abstract: The disclosure provides a liquid crystal device including a liquid crystal composition containing a dichroic dye (dye-containing liquid crystal composition) that is in a light transmissive state when no voltage is applied to the transparent electrode and in a light scattering state when voltage is applied. The liquid crystal composition exhibits a negative dielectric constant anisotropy. The haze value of the liquid crystal device is 10% or less when no voltage is applied at 25° C., and the haze value is 50% or more when a rectangular wave voltage (AC 50 V, 60 Hz) is applied. The voltage holding ratio of the dye-containing liquid crystal composition is 60% or less at 25° C. The liquid crystal device provided by the disclosure is used as a component to provide a liquid crystal display apparatus, a light control apparatus, or a light transmitting apparatus with a high contrast.Type: ApplicationFiled: March 3, 2023Publication date: September 14, 2023Applicant: DIC CorporationInventors: Yuichi Inoue, Kenta Tojo, Naomi Hatano, Kento Kawakita
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Patent number: 11584853Abstract: Provided are a compound represented by the following general formula (1) and a liquid crystal composition containing the compound, and a liquid crystal display device or a light control device having the liquid crystal composition. The compound represented by general formula (1) has both a large dichroic ratio and high solubility in the host liquid crystal. In addition, it has excellent chemical stability at a level usable as a device. Therefore, by using the compound represented by general formula (1) as a component of a GH-type liquid crystal composition, it is possible to provide a liquid crystal display device or a light control device with high contrast.Type: GrantFiled: September 8, 2021Date of Patent: February 21, 2023Assignee: DIC CORPORATIONInventors: Kento Kawakita, Kenta Tojo, Ayaki Hosono
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Publication number: 20220073750Abstract: Provided are a compound represented by the following general formula (1) and a liquid crystal composition containing the compound, and a liquid crystal display device or a light control device having the liquid crystal composition. The compound represented by general formula (1) has both a large dichroic ratio and high solubility in the host liquid crystal. In addition, it has excellent chemical stability at a level usable as a device. Therefore, by using the compound represented by general formula (1) as a component of a GH-type liquid crystal composition, it is possible to provide a liquid crystal display device or a light control device with high contrast.Type: ApplicationFiled: September 8, 2021Publication date: March 10, 2022Applicant: DIC CorporationInventors: Kento Kawakita, Kenta Tojo, Ayaki Hosono
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Patent number: 10544365Abstract: A liquid crystal composition that has a positive dielectric anisotropy and a sufficiently low viscosity and that causes no display defects when used in liquid crystal display devices is provided without decreasing or increasing the refractive index anisotropy or nematic phase-isotropic liquid phase transition temperature. This liquid crystal composition contains at least one compound selected from compounds represented by general formula (LC0) and at least one compound selected from the group consisting of compounds represented by general formulas (LC1) to (LC5). This liquid crystal composition can be used to provide a reliable liquid crystal display device capable of maintaining a high voltage-holding ratio at high temperatures. This liquid crystal display device is highly practical as a liquid crystal display and is effective in achieving quick response without significantly decreasing the cell gap.Type: GrantFiled: August 21, 2014Date of Patent: January 28, 2020Assignee: DIC CORPORATIONInventors: Masakazu Kaneoya, Kiyofumi Takeuchi, Masashi Osawa, Kenta Tojo, Tetsuo Kusumoto
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Patent number: 9822301Abstract: The present invention provides a compound represented by general formula (1) as well as a liquid crystal composition containing this compound and a liquid crystal display using this liquid crystal composition. Using the compound represented by general formula (1) as a component of a liquid crystal composition makes it possible to obtain a liquid crystal composition having a low viscosity (?), a high ?n, suitable T-i, high miscibility with other liquid crystal compounds, and presenting a liquid crystal phase over a wide temperature range. This is therefore extremely useful as a structural component of a liquid crystal composition for a liquid crystal display requiring a high speed response.Type: GrantFiled: November 13, 2014Date of Patent: November 21, 2017Assignee: DIC CORPORATIONInventors: Kenta Tojo, Takashi Matsumoto
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Patent number: 9637466Abstract: The present invention relates to a compound having 2,6-difluorophenyl ether structure and useful as an organic electronic material and a medicine/agrochemical, particularly a material for liquid crystal display devices, and also relates to an effective method for producing the same. The present invention provides a compound represented by general formula (1) and also provides a liquid crystal composition containing the compound and a liquid crystal display device using the liquid crystal composition. A liquid crystal composition exhibiting low viscosity and a liquid crystal phase within a wide temperature range can be produced by using the compound represented by the general formula (1) as a component of the liquid crystal composition. Thus, the compound is very useful as a constituent component of a liquid crystal composition for a liquid crystal display device required to have, fast response.Type: GrantFiled: July 15, 2014Date of Patent: May 2, 2017Assignee: DIC CORPORATIONInventors: Kenta Tojo, Tetsuo Kusumoto
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Patent number: 9605208Abstract: A liquid crystal composition exhibits a positive dielectric anisotropy and sufficiently low viscosity without decreasing or increasing refractive index anisotropy or nematic phase-isotropic liquid phase transition temperature, and does not cause display failures. The liquid crystal composition contains one or more compounds selected from compounds represented by general formula (LC0) and one or more compounds selected from a group of compounds represented by general formula (LC1) to general formula (LC5), in which the liquid crystal composition contains one or more compounds in which at least one of A01, A02, and A11 to A42 in general formulae (LC0) to (LC4) represents a tetrahydropyran-2,5-diyl group.Type: GrantFiled: July 24, 2013Date of Patent: March 28, 2017Assignee: DIC CORPORATIONInventors: Masakazu Kaneoya, Kiyofumi Takeuchi, Masashi Osawa, Kenta Tojo, Tetsuo Kusumoto
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Patent number: 9587175Abstract: The present invention relates to a nematic liquid crystal composition useful as an electro-optic liquid crystal display material and having a positive dielectric anisotropy (??). The liquid crystal composition has refractive index anisotropy (?n) adjusted to a desired level, a sufficiently low viscosity (?), and a positive dielectric anisotropy (??) while degradation of the temperature range of the nematic phase is avoided by suppressing the decrease in nematic phase-isotropic liquid phase transition temperature (Tni) and the increase in lower limit temperature of the nematic phase. The liquid crystal composition contains one or more compounds selected from compounds represented by general formula (LC0) and one or more compounds selected from a group of compounds represented by general formula (LC1) to general formula (LC5).Type: GrantFiled: July 24, 2013Date of Patent: March 7, 2017Assignee: DIC CORPORATIONInventors: Masakazu Kaneoya, Kiyofumi Takeuchi, Masashi Osawa, Kenta Tojo, Tetsuo Kusumoto
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Patent number: 9573923Abstract: The present invention relates to a compound having a 2,6-difluorophenylether structure useful as organic electronic materials, pharmaceuticals and agrochemicals, and in particular, liquid crystal display device materials. Provided are a compound represented by general formula (1): and a liquid crystal composition containing the compound and a liquid crystal display device that uses the liquid crystal composition. Since the compound represented by general formula (1) is used as a component of a liquid crystal composition, a liquid crystal composition that exhibits low viscosity and a liquid crystal phase over a wide temperature range can be obtained. Thus, the compound is particularly useful as a component of a liquid crystal composition for high-response-speed liquid crystal display devices.Type: GrantFiled: August 28, 2014Date of Patent: February 21, 2017Assignee: DIC CORPORATIONInventors: Kenta Tojo, Tetsuo Kusumoto
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Publication number: 20160326433Abstract: The present invention provides a compound represented by general formula (1) as well as a liquid crystal composition containing this compound and a liquid crystal display using this liquid crystal composition. Using the compound represented by general formula (1) as a component of a liquid crystal composition makes it possible to obtain a liquid crystal composition having a low viscosity (?), a high ?n, suitable T-i, high miscibility with other liquid crystal compounds, and presenting a liquid crystal phase over a wide temperature range. This is therefore extremely useful as a structural component of a liquid crystal composition for a liquid crystal display requiring a high speed response.Type: ApplicationFiled: November 13, 2014Publication date: November 10, 2016Applicant: DIC CorporationInventors: Kenta Tojo, Takashi Matsumoto
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Publication number: 20160186059Abstract: A liquid crystal composition that has a positive dielectric anisotropy and a sufficiently low viscosity and that causes no display defects when used in liquid crystal display devices is provided without decreasing or increasing the refractive index anisotropy or nematic phase-isotropic liquid phase transition temperature. This liquid crystal composition contains at least one compound selected from compounds represented by general formula (LC0) and at least one compound selected from the group consisting of compounds represented by general formulas (LC1) to (LC5). This liquid crystal composition can be used to provide a reliable liquid crystal display device capable of maintaining a high voltage-holding ratio at high temperatures. This liquid crystal display device is highly practical as a liquid crystal display and is effective in achieving quick response without significantly decreasing the cell gap.Type: ApplicationFiled: August 21, 2014Publication date: June 30, 2016Applicant: DIC CorporationInventors: Masakazu Kaneoya, Kiyofumi Takeuchi, Masashi Osawa, Kenta Tojo, Tetsuo Kusumoto
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Publication number: 20160159765Abstract: The present invention relates to a compound having a 2,6-difluorophenylether structure useful as organic electronic materials, pharmaceuticals and agrochemicals, and in particular, liquid crystal display device materials. Provided are a compound represented by general formula (1): and a liquid crystal composition containing the compound and a liquid crystal display device that uses the liquid crystal composition. Since the compound represented by general formula (1) is used as a component of a liquid crystal composition, a liquid crystal composition that exhibits low viscosity and a liquid crystal phase over a wide temperature range can be obtained. Thus, the compound is particularly useful as a component of a liquid crystal composition for high-response-speed liquid crystal display devices.Type: ApplicationFiled: August 28, 2014Publication date: June 9, 2016Applicant: DIC CORPORATIONInventors: Kenta Tojo, Tetsuo Kusumoto
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Publication number: 20160152589Abstract: The present invention relates to a compound having 2,6-difluorophenyl ether structure and useful as an organic electronic material and a medicine/agrochemical, particularly a material for liquid crystal display devices, and also relates to an effective method for producing the same. The present invention provides a compound represented by general formula (1) and also provides a liquid crystal composition containing the compound and a liquid crystal display device using the liquid crystal composition. A liquid crystal composition exhibiting low viscosity and a liquid crystal phase within a wide temperature range can be produced by using the compound represented by the general formula (1) as a component of the liquid crystal composition. Thus, the compound is very useful as a constituent component of a liquid crystal composition for a liquid crystal display device required to have, fast response.Type: ApplicationFiled: July 15, 2014Publication date: June 2, 2016Applicant: DIC CORPORATIONInventors: Kenta TOJO, Tetsuo KUSUMOTO
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Patent number: 9321961Abstract: Provided is a liquid crystal composition having a positive dielectric anisotropy, the liquid crystal composition containing two or more compounds selected from compounds represented by general formula (LC0-1) to general formula (LC0-3), and one or more compounds selected from groups of compounds represented by general formula (LC1) to general formula (LC5). The liquid crystal composition has features of a large ?? and a low viscosity, and provides a practical, highly reliable liquid crystal display element that can realize low-voltage driving and high-speed response. The liquid crystal composition is useful for an active matrix driving liquid crystal display element. The liquid crystal composition can be applied to a liquid crystal display element of an IPS mode or the like.Type: GrantFiled: August 29, 2013Date of Patent: April 26, 2016Assignee: DIC CORPORATION (TOKYO)Inventors: Masakazu Kaneoya, Kiyofumi Takeuchi, Masashi Osawa, Kenta Tojo, Tetsuo Kusumoto
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Patent number: 9315727Abstract: There is provided a liquid crystal composition containing the compound represented by the general formula (1) and a liquid crystal display device that uses the liquid crystal composition. The compound represented by the general formula (1) has high ??, high Tni, and good miscibility with other liquid crystal compounds. Therefore, a liquid crystal composition that has high ?? and exhibits a liquid crystal phase in a wide temperature range can be obtained by using the compound represented by the general formula (1) as a component of the liquid crystal composition. Thus, the compound is very useful as a constituent component of the liquid crystal composition for liquid crystal display devices.Type: GrantFiled: September 19, 2013Date of Patent: April 19, 2016Assignee: DIC CORPORATION (TOKYO)Inventors: Kenta Tojo, Tetsuo Kusumoto
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Publication number: 20150322343Abstract: Provided is a liquid crystal composition that has a positive dielectric anisotropy (??) and a refractive index anisotropy (?n) adjusted to a desired level, and sufficiently low viscosity (?) without degrading the nematic phase temperature range. The liquid crystal composition having positive dielectric anisotropy comprises one or more compounds selected from compounds represented by general formula (LC0) and one or more compounds selected from the group of compounds represented by general formula (LC1) to general formula (LC5), wherein the liquid crystal composition comprises a compound in which at least one of Y01 to Y41 in general formula (LC0) to general formula (LC4) represents a fluorinated C2-C5 alkyl, alkoxy, alkenyl, or alkenyloxy group.Type: ApplicationFiled: September 5, 2013Publication date: November 12, 2015Applicant: DIC CORPORATIONInventors: Masakazu Kaneoya, Kiyofumi Takeuchi, Masashi Osawa, Kenta Tojo, Tetsuo Kusumoto
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Patent number: 9181484Abstract: There is provided a compound having a good miscibility with another liquid crystal compound and having a combination of a low viscosity (?), high storage stability, and high T?i even after being used to produce a liquid crystal composition. In particular, it is a compound having a 2-fluorophenyloxymethane structure is provided. Since the compound having a 2-fluorophenyloxymethane structure is highly miscible with another liquid crystal compound, using the compound having a 2-fluorophenyloxymethane structure as a component of a liquid crystal composition enables a production of a liquid crystal composition which exhibits a liquid crystal phase at low viscosity and in a wide temperature range and which has a high storage stability and enables production of a liquid crystal display device which responds fast and which has excellent display characteristics.Type: GrantFiled: April 24, 2013Date of Patent: November 10, 2015Assignee: DIC CORPORATIONInventors: Kenta Tojo, Tetsuo Kusumoto, Masashi Osawa, Masakazu Kaneoya, Kiyofumi Takeuchi
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Publication number: 20150284634Abstract: A liquid crystal composition having positive dielectric anisotropy and sufficiently low viscosity without decreasing refractive index anisotropy or increasing nematic phase-isotropic liquid phase transition temperature, and prevents display failures is provided. The liquid crystal composition comprises one or more compounds selected from compounds represented by general formula (LC0) and one or more compounds selected from the group of compounds represented by general formula (LC1) to general formula (LC5), wherein the liquid crystal composition comprises one or more compounds in which at least one of A21 to A42 in general formula (LC2) to general formula (LC4) represents a tetrahydropyran-2,5-diyl group.Type: ApplicationFiled: September 5, 2013Publication date: October 8, 2015Applicant: DIC CorporationInventors: Masakazu Kaneoya, Kiyofumi Takeuchi, Masashi Osawa, Kenta Tojo, Tetsuo Kusumoto
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Publication number: 20150259599Abstract: There is provided a liquid crystal composition containing the compound represented by the general formula (1) and a liquid crystal display device that uses the liquid crystal composition. The compound represented by the general formula (1) has high ??, high Tni, and good miscibility with other liquid crystal compounds. Therefore, a liquid crystal composition that has high ?? and exhibits a liquid crystal phase in a wide temperature range can be obtained by using the compound represented by the general formula (1) as a component of the liquid crystal composition. Thus, the compound is very useful as a constituent component of the liquid crystal composition for liquid crystal display devices.Type: ApplicationFiled: September 19, 2013Publication date: September 17, 2015Applicant: DIC CorporationInventors: Kenta Tojo, Tetsuo Kusumoto
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Publication number: 20150218451Abstract: Provided is a liquid crystal composition having a positive dielectric anisotropy, the liquid crystal composition containing two or more compounds selected from compounds represented by general formula (LC0-1) to general formula (LC0-3), and one or more compounds selected from groups of compounds represented by general formula (LC1) to general formula (LC5). The liquid crystal composition has features of a large ?? and a low viscosity, and provides a practical, highly reliable liquid crystal display element that can realize low-voltage driving and high-speed response. The liquid crystal composition is useful for an active matrix driving liquid crystal display element. The liquid crystal composition can be applied to a liquid crystal display element of an IPS mode or the like.Type: ApplicationFiled: August 29, 2013Publication date: August 6, 2015Applicant: DIC CORPORATIONInventors: Masakazu Kaneoya, Kiyofumi Takeuchi, Masashi Osawa, Kenta Tojo, Tetsuo Kusumoto