Patents by Inventor Masafumi Asakai

Masafumi Asakai 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: 9835965
    Abstract: To provide a charge control agent and a toner having a superior charging characteristic. A charge control agent containing a bis-phthalimide derivative represented by formula. Thus, it is possible to provide a safe, negative chargeability charge control agent with which the rate of rise of the charge can be increased, and which has a high charging amount and poses no problem in terms of waste regulations. Furthermore, it is possible to provide a negatively chargeable toner (and particularly, a negatively chargeable polymerized toner) for electrostatic image development which uses this charging control agent and has a superior charging characteristic.
    Type: Grant
    Filed: September 24, 2014
    Date of Patent: December 5, 2017
    Assignee: HODOGAYA CHEMICAL CO., LTD.
    Inventors: Masaki Okubo, Ikuo Kimura, Masami Ito, Motonori Tsuji, Takeshi Yamamoto, Masaya Tojo, Masafumi Asakai, Tetsuya Yoshida
  • Patent number: 9703223
    Abstract: The present invention provides a toner that includes a charge control agent containing one or two or more resorcin derivatives represented by the following formula (1), a colorant, and a binder resin.
    Type: Grant
    Filed: September 24, 2014
    Date of Patent: July 11, 2017
    Assignee: HODOGAYA CHEMICAL CO., LTD.
    Inventors: Masaki Okubo, Motonori Tsuji, Masami Ito, Masaya Tojo, Masafumi Asakai, Tetsuya Yoshida
  • Publication number: 20160216628
    Abstract: To provide a charge control agent and a toner having a superior charging characteristic. A charge control agent containing a bis-phthalimide derivative represented by formula. Thus, it is possible to provide a safe, negative chargeability charge control agent with which the rate of rise of the charge can be increased, and which has a high charging amount and poses no problem in terms of waste regulations. Furthermore, it is possible to provide a negatively chargeable toner (and particularly, a negatively chargeable polymerized toner) for electrostatic image development which uses this charging control agent and has a superior charging characteristic.
    Type: Application
    Filed: September 24, 2014
    Publication date: July 28, 2016
    Inventors: Masaki OKUBO, Ikuo KIMURA, Masami ITO, Motonori TSUJI, Takeshi YAMAMOTO, Masaya TOJO, Masafumi ASAKAI, Tetsuya YOSHIDA
  • Publication number: 20160209769
    Abstract: The present invention provides a toner that includes a charge control agent containing one or two or more resorcin derivatives represented by the following formula (1), a colorant, and a binder resin.
    Type: Application
    Filed: September 24, 2014
    Publication date: July 21, 2016
    Applicant: HODOGAYA CHEMICAL CO., LTD
    Inventors: Masaki OKUBO, Motonori TSUJI, Masami ITO, Masaya TOJO, Masafumi ASAKAI, Tetsuya YOSHIDA
  • Patent number: 8900785
    Abstract: A charge control agent comprises a barbituric acid derivative represented by the following general formula (1): wherein R1 to R8 are alkyl groups, cycloalkyl groups or aryl groups, V, W, X, Y and Z are carbon atoms or nitrogen atoms, at least two of which being carbon atoms, and p, q, r, s and t are the numbers of 0 or 1.
    Type: Grant
    Filed: September 2, 2011
    Date of Patent: December 2, 2014
    Assignee: Hodogaya Chemical Co., Ltd.
    Inventors: Ikuo Kimura, Masami Ito, Masaya Tojou, Kanae Hiraishi, Masafumi Asakai
  • Publication number: 20140205945
    Abstract: To provide a charge controlling agent for electrophotography, which presents sufficient triboelectric chargeability to a toner, is useful particularly for a color toner and further for a polymerized toner, increases a charge rising rate, has a high electric charge amount, is excellent in charging characteristics, stability over time and environmental stability and yet is safe without posing any problem regarding waste regulations, and a negatively chargeable toner for developing an electrostatic image, which uses such a charge controlling agent and which has a high charging performance.
    Type: Application
    Filed: January 24, 2014
    Publication date: July 24, 2014
    Applicant: HODOGAYA CHEMICAL CO., LTD.
    Inventors: Ikuo KIMURA, Masami ITO, Masaya TOJO, Masafumi ASAKAI
  • Publication number: 20130266895
    Abstract: The present invention provides a charge control agent containing, as an active substance(s), one or two or more hydantoin derivatives represented by the following formula (1): wherein R1 and R2, which may be identical to or different from each other, represent a hydrogen atom, etc.; R3 represents a hydrogen atom, etc.; R4, to R8, which may be identical to or different from each other, represent a hydrogen atom, a chlorine atom, a linear or branched alkyl group having 1 to 8 carbon atoms which may have a substituent, etc.; R3, to R8 may be joined to each other to form a ring; and V, W, X, Y and Z represent a carbon atom or a nitrogen atom, and 0 to 3 of V, W, X, Y and Z are nitrogen atoms which have no substituent of R4 to R8.
    Type: Application
    Filed: January 17, 2012
    Publication date: October 10, 2013
    Applicant: HODOGAYA CHEMICAL CO., LTD.
    Inventors: Ikuo Kimura, Motonori Tsuji, Masaya Tojo, Masafumi Asakai
  • Publication number: 20130157190
    Abstract: [Problems] To provide a charge control agent which contains no heavy metal component, therefore, does not adversely affect the environment and, besides, is colorless or is light-colored lending itself well to be applied to colored toners, and is little affected by the environmental conditions, and exhibits the effect of imparting high charging power even when it is used for polymerized toners. [Means for Solution] The charge control agent comprises a barbituric acid derivative represented by the following general formula (1): wherein R1 to R8 are alkyl groups, cycloalkyl groups or aryl groups, V, W, X, Y and Z are carbon atoms or nitrogen atoms, at least two of which being carbon atoms, and p, q, r, s and t are the numbers of 0 or 1.
    Type: Application
    Filed: September 2, 2011
    Publication date: June 20, 2013
    Applicant: HODOGAYA CHEMICAL CO., LTD.
    Inventors: Ikuo Kimura, Masami Ito, Masaya Tojou, Kanae Hiraishi, Masafumi Asakai
  • Publication number: 20130149641
    Abstract: To provide a charge controlling agent for electrophotography, which presents sufficient triboelectric chargeability to a toner, is useful particularly for a color toner and further for a polymerized toner, increases a charge rising rate, has a high electric charge amount, is excellent in charging characteristics, stability over time and environmental stability and yet is safe without posing any problem regarding waste regulations, and a negatively chargeable toner for developing an electrostatic image, which uses such a charge controlling agent and which has a high charging performance.
    Type: Application
    Filed: September 13, 2011
    Publication date: June 13, 2013
    Applicant: HODOGAYA CHEMICAL CO., LTD.
    Inventors: Ikuo Kimura, Masami Ito, Masaya Tojo, Masafumi Asakai