Patents by Inventor Takahito Ikuma

Takahito Ikuma 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).

  • Patent number: 11876224
    Abstract: An object of the present invention is to provide a negative electrode active material having excellent charge/discharge characteristics (charge and discharge capacities, initial coulombic efficiency, and cycle characteristics). The object is achieved by providing a negative electrode active material containing: a silicon-based inorganic compound (a) composed of silicon (excluding zerovalent silicon), oxygen, and carbon; and silicon (zerovalent) (b). The equivalent constituent ratio [Q units/(D units+T units+Q units)] indicating the chemical bonding state (D units [SiO2C2], T units [SiO3C], Q units[SiO4]) of the silicon (excluding zerovalent silicon) present in the silicon-based inorganic compound (a) is within the range of from 0.30 to 0.80 inclusive.
    Type: Grant
    Filed: November 27, 2018
    Date of Patent: January 16, 2024
    Assignee: DIC Corporation
    Inventors: Peixin Zhu, Shinji Kato, Ryuuichi Kiyooka, Katsuhito Kuroki, Satoshi Katano, Takahito Ikuma
  • Patent number: 11655310
    Abstract: Provided are: a fine cellulose fiber that is superior in handling properties and that can suitably be used as a reinforcing material or the like for resin; a production method of the fine cellulose fiber; and a slurry and a composite comprising the fine cellulose fibers. The present invention pertains to fine cellulose fibers comprising a carbamate group. The degree of substitution with the carbamate group with respect to hydroxy groups in the fine cellulose fibers is preferably no less than 0.05 and no greater than 0.5. The present invention pertains to a slurry comprising the fine cellulose fibers, to a composite comprising the fine cellulose fibers and a resin, and to a production method of the fine cellulose fibers, comprising performing a heat treatment on a mixture of a plant raw material and urea or the like, and performing a miniaturization treatment of the plant raw material.
    Type: Grant
    Filed: June 13, 2018
    Date of Patent: May 23, 2023
    Assignees: KYOTO UNIVERSITY, DAIO PAPER CORPORATION
    Inventors: Yoshinobu Tsujii, Keita Sakakibara, Koji Tanaka, Takahito Ikuma, Junya Okawa, Ikko Matsusue
  • Publication number: 20220069296
    Abstract: Silicon nanoparticles for negative electrode active material in lithium ion secondary batteries are provided. The silicon nanoparticles have a 29Si-NMR peak which has a half width of 20 ppm to 50 ppm centered at ?80 ppm and is broad ranging from 50 ppm to ?150 ppm. The silicon nanoparticles have a length in the major axis direction of 70 to 300 nm and a thickness of 15 to 70 nm or less.
    Type: Application
    Filed: November 12, 2019
    Publication date: March 3, 2022
    Inventors: Peixin ZHU, Kenichi KAWASE, Shunichi OOTSUKA, Takahito IKUMA
  • Publication number: 20200365893
    Abstract: An object of the present invention is to provide a negative electrode active material having excellent charge/discharge characteristics (charge and discharge capacities, initial coulombic efficiency, and cycle characteristics). The object is achieved by providing a negative electrode active material containing: a silicon-based inorganic compound (a) composed of silicon (excluding zerovalent silicon), oxygen, and carbon; and silicon (zerovalent) (b). The equivalent constituent ratio [Q units/(D units+T units+Q units)] indicating the chemical bonding state (D units [SiO2C2], T units [SiO3C], Q units[SiO4]) of the silicon (excluding zerovalent silicon) present in the silicon-based inorganic compound (a) is within the range of from 0.30 to 0.80 inclusive.
    Type: Application
    Filed: November 27, 2018
    Publication date: November 19, 2020
    Applicant: DIC Corporation
    Inventors: Peixin ZHU, Shinji KATO, Ryuuichi KIYOOKA, Katsuhito KUROKI, Satoshi KATANO, Takahito IKUMA
  • Publication number: 20200115471
    Abstract: Provided are: a fine cellulose fiber that is superior in handling properties and that can suitably be used as a reinforcing material or the like for resin; a production method of the fine cellulose fiber; and a slurry and a composite comprising the fine cellulose fibers. The present invention pertains to fine cellulose fibers comprising a carbamate group. The degree of substitution with the carbamate group with respect to hydroxy groups in the fine cellulose fibers is preferably no less than 0.05 and no greater than 0.5. The present invention pertains to a slurry comprising the fine cellulose fibers, to a composite comprising the fine cellulose fibers and a resin, and to a production method of the fine cellulose fibers, comprising performing a heat treatment on a mixture of a plant raw material and urea or the like, and performing a miniaturization treatment of the plant raw material.
    Type: Application
    Filed: June 13, 2018
    Publication date: April 16, 2020
    Applicants: Kyoto University, DAIO PAPER CORPORATION
    Inventors: Yoshinobu Tsujii, Keita Sakakibara, Koji Tanaka, Takahito Ikuma, Junya Okawa, Ikko Matsusue
  • Publication number: 20180362405
    Abstract: An object is to establish a technique for producing a resin composite material at low cost. A resin composition contains cellulose fibers, a fibrillation aid, and a resin.
    Type: Application
    Filed: December 1, 2016
    Publication date: December 20, 2018
    Applicants: Kyoto University, DIC Corporation
    Inventors: Yoshinobu Tsujii, Keita Sakakibara, Tetsuya Harada, Takahito Ikuma, Junya Okawa, Ikko Matsusue, Junji Shinya
  • Patent number: 9902820
    Abstract: Provided herein is a cellulose nanofiber-containing composition producing method for producing a cellulose nanofiber-containing composition that can be easily combined with compounds having a reactive double-bond group, and that contains only a small amount of uncured material that acts as a plasticizer in a molded product, using a simple producing method that does not require any process involving solvent displacement or solvent removal. A high-strength molded body prepared by using the cellulose nanofiber-containing composition is also provided. In refining cellulose in a mixture containing a compound having a reactive double-bond group and a hydroxyl group of 10 KOHmg/g or less and a defibrating resin as essential components, the cellulose has a moisture content of 4 to 25 parts by mass with respect to 100 parts by mass of the amount of the cellulose converted on the assumption that the percentage moisture of the cellulose is 0%.
    Type: Grant
    Filed: May 20, 2014
    Date of Patent: February 27, 2018
    Assignee: DIC Corporation
    Inventors: Takahito Ikuma, Tetsuya Harada, Mitsuyuki Kanzaki
  • Patent number: 9822241
    Abstract: Provided herein is a cellulose nanofiber that can be easily combined with a compound having a reactive double-bond group and that can provide a molded article which contains only a small amount of an uncured material that acts as a plasticizer in a molded product, using a simple producing method that does not require any process involving solvent displacement or solvent removal. A high-strength resin composition or molded body prepared by using the cellulose nanofiber is also provided. In refining cellulose in the presence of a compound having a reactive double bond and a hydroxyl value of 200 KOHmg/g or more, the cellulose has a moisture content of 4 to 25 parts by mass with respect to 100 parts by mass of the amount of the cellulose converted on the assumption that the percentage moisture of the cellulose is 0%.
    Type: Grant
    Filed: May 20, 2014
    Date of Patent: November 21, 2017
    Assignees: DIC Corporation, NIPPON PAPER INDUSTRIES CO., LTD.
    Inventors: Takahito Ikuma, Tetsuya Harada, Mitsuyuki Kanzaki
  • Patent number: 9624606
    Abstract: The present invention provides a method for producing cellulose nanofibers, the method including fibrillating cellulose in a modified epoxy resin (A) having a hydroxyl value of 100 mgKOH/g or more. Also, the present invention provides cellulose nanofibers produced by the production method and a master batch containing the cellulose nanofibers and the modified epoxy resin (A). Further, present invention provides a resin composition containing the master batch and a curing agent (D), and provides a molded product produced by molding the resin composition.
    Type: Grant
    Filed: March 28, 2013
    Date of Patent: April 18, 2017
    Assignee: DIC Corporation
    Inventors: Takeshi Yamazaki, Takahito Ikuma, Tetsuya Harada, Tetsuya Yamazaki, Mari Minowa, Masakazu Yoshizawa
  • Publication number: 20170015799
    Abstract: The present invention provides a fiber-reinforced resin composite as a fiber-reinforced resin composite (E) including a fiber-reinforced resin (C), which contains a reinforcing fiber (A) and a matrix resin (B), and a reinforcing material (D), in which the reinforcing material (D) contains a cellulose nanofiber (F), and the cellulose nanofiber (F) is obtained by micronizing cellulose in a fibrillated resin (G), and provides a reinforced matrix resin for the fiber-reinforced resin. The present invention also provides a fiber-reinforced resin composite in which the cellulose nanofiber (F) is a modified cellulose nanofiber (F1) that is obtained by micronizing cellulose in the fibrillated resin (G) and then reacting the cellulose with a cyclic polybasic acid anhydride (J).
    Type: Application
    Filed: September 28, 2016
    Publication date: January 19, 2017
    Inventors: Takeshi Yamazaki, Tetsuya Harada, Takahito Ikuma, Hironobu Takizawa
  • Publication number: 20160244597
    Abstract: Provided herein is a cellulose nanofiber that can be easily combined with a compound having a reactive double-bond group and that can provide a molded article which contains only a small amount of an uncured material that acts as a plasticizer in a molded product, using a simple producing method that does not require any process involving solvent displacement or solvent removal. A high-strength resin composition or molded body prepared by using the cellulose nanofiber is also provided. In refining cellulose in the presence of a compound having a reactive double bond and a hydroxyl value of 200 KOHmg/g or more, the cellulose has a moisture content of 4 to 25 parts by mass with respect to 100 parts by mass of the amount of the cellulose converted on the assumption that the percentage moisture of the cellulose is 0%.
    Type: Application
    Filed: May 20, 2014
    Publication date: August 25, 2016
    Applicant: DIC CORPORATION
    Inventors: Takahito Ikuma, Tetsuya Harada, Mitsuyuki Kanzaki
  • Publication number: 20160237229
    Abstract: Provided herein is a cellulose nanofiber-containing composition producing method for producing a cellulose nanofiber-containing composition that can be easily combined with compounds having a reactive double-bond group, and that contains only a small amount of uncured material that acts as a plasticizer in a molded product, using a simple producing method that does not require any process involving solvent displacement or solvent removal. A high-strength molded body prepared by using the cellulose nanofiber-containing composition is also provided. In refining cellulose in a mixture containing a compound having a reactive double-bond group and a hydroxyl group of 10 KOHmg/g or less and a defibrating resin as essential components, the cellulose has a moisture content of 4 to 25 parts by mass with respect to 100 parts by mass of the amount of the cellulose converted on the assumption that the percentage moisture of the cellulose is 0%.
    Type: Application
    Filed: May 20, 2014
    Publication date: August 18, 2016
    Inventors: Takahito IKUMA, Tetsuya HARADA, Mitsuyuki KANZAKI
  • Publication number: 20150171395
    Abstract: Provided are a modified-cellulose-nanofiber containing polyethylene fine porous film containing modified cellulose nanofibers having alkyl or alkenyl groups with 4 to 30 carbon atoms and a modified-cellulose-nanofiber containing polyethylene fine porous film containing modified cellulose nanofibers prepared by fibrillating cellulose into cellulose nanofibers in a nonaqueous resin and modifying the cellulose nanofibers. Also provided are a separator made of such a fine porous film and a lithium-ion battery including such a separator.
    Type: Application
    Filed: July 16, 2013
    Publication date: June 18, 2015
    Inventors: Takahito Ikuma, Satoshi Katano, Tetsuya Harada
  • Publication number: 20150166741
    Abstract: Provided is a method for producing modified cellulose nanofibers, the method including the steps of fibrillating cellulose in a fibrillation resin to produce cellulose nanofibers and reacting hydroxyl groups of the cellulose nanofibers with a cyclic polybasic acid anhydride (B) in the fibrillation resin to produce modified cellulose nanofibers. Also provided are modified cellulose nanofibers produced by the production method, a resin composition including the modified cellulose nanofibers, and a molded body formed of the resin composition.
    Type: Application
    Filed: March 28, 2013
    Publication date: June 18, 2015
    Applicant: DIC Corporation
    Inventors: Takahito Ikuma, Takeshi Yamazaki, Tomoaki Harada, Tetsuya Harada
  • Publication number: 20150087750
    Abstract: The present invention provides a method for producing cellulose nanofibers, the method including fibrillating cellulose in a modified epoxy resin (A) having a hydroxyl value of 100 mgKOH/g or more. Also, the present invention provides cellulose nanofibers produced by the production method and a master batch containing the cellulose nanofibers and the modified epoxy resin (A). Further, present invention provides a resin composition containing the master batch and a curing agent (D), and provides a molded product produced by molding the resin composition.
    Type: Application
    Filed: March 28, 2013
    Publication date: March 26, 2015
    Inventors: Takeshi Yamazaki, Takahito Ikuma, Tetsuya Harada, Tetsuya Yamazaki, Mari Minowa, Masakazu Yoshizawa
  • Publication number: 20150045495
    Abstract: There is provided a method for producing a pigment composition which contains a polymer-treated pigment (D) containing an azo lake pigment (A) and an aqueous polymer (C) precipitated with a polyvalent metal salt (B) and also contains a polymer (F) obtained by polymerizing a polymerizable unsaturated monomer (E) in the presence of the polymer-treated pigment (D). The method includes: synthesizing an azo dye by coupling a coupler component with a diazo component obtained by diazotizing an aromatic amine; and preparing the polymer-treated pigment (D). The method also includes producing the polymer (F) by polymerizing the polymerizable unsaturated monomer (E) in the presence of the polymer-treated pigment (D) to coat the polymer-treated pigment (D) with the polymer (F).
    Type: Application
    Filed: September 6, 2012
    Publication date: February 12, 2015
    Applicant: DIC CORPORATION
    Inventors: Yasuyo Hirose, Jouji Kawamura, Takahito Ikuma, Hiroshi Kinoshita
  • Publication number: 20150005413
    Abstract: The present invention provides a fiber-reinforced resin composite as a fiber-reinforced resin composite (E) including a fiber-reinforced resin (C), which contains a reinforcing fiber (A) and a matrix resin (B), and a reinforcing material (D), in which the reinforcing material (D) contains a cellulose nanofiber (F), and the cellulose nanofiber (F) is obtained by micronizing cellulose in a fibrillated resin (G), and provides a reinforced matrix resin for the fiber-reinforced resin. The present invention also provides a fiber-reinforced resin composite in which the cellulose nanofiber (F) is a modified cellulose nanofiber (F1) that is obtained by micronizing cellulose in the fibrillated resin (G) and then reacting the cellulose with a cyclic polybasic acid anhydride (J).
    Type: Application
    Filed: February 15, 2013
    Publication date: January 1, 2015
    Applicant: DIC CORPORATION
    Inventors: Takeshi Yamazaki, Tetsuya Harada, Takahito Ikuma, Hironobu Takizawa