Patents by Inventor Hirotaka Kita

Hirotaka Kita 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: 9993394
    Abstract: Provided is a dental restorative composition that has good handling properties when in the form of a paste having yet to be cured and that has light diffusion ability and transparency when in the form of a cured product. The dental restorative composition includes a polymerizable monomer, a polymerization initiator, an inorganic filler (C) having an average particle diameter of 0.1 to 1 ?m, an organic-inorganic composite filler (D) having an average particle diameter of 1 ?m or more and less than 10 ?m, and an organic-inorganic composite filler (E) having an average particle diameter of 10 to 50 ?m. An absolute value of a difference between a refractive index (Cd) of the inorganic filler (C) and a refractive index (Ad) of a polymer of the polymerizable monomer is 0.01 or less, an absolute value of a difference between the refractive index (Ad) and one of a refractive index (Dd) of the organic-inorganic composite filler (D) and a refractive index (Ed) of the organic-inorganic composite filler (E) is 0.
    Type: Grant
    Filed: February 17, 2015
    Date of Patent: June 12, 2018
    Assignee: KURARAY NORITAKE DENTAL INC.
    Inventors: Hirotaka Kita, Michiya Kawana, Eiichi Terakawa
  • Patent number: 9675527
    Abstract: The present invention provides a dental color tone adjustment material kit that has improved properties in terms of surface drying and of discoloration after curing and that enables adjustment to a desired color tone. The present invention relates to a dental color tone adjustment material kit including: a primer composition (A) including an acid group-containing polymerizable monomer (a) and a volatile organic solvent (b); and a dental color tone adjustment material B including a polymerizable monomer (d), a polymerization initiator (e), particle aggregates (f) that are chain aggregates of ultrafine filler particles having an average primary particle diameter of 1 to 50 nm, titanium dioxide (g), and a pigment (h). The monomer (a) accounts for 0.05 to 45 weight % of the primer composition (A), and the organic solvent (b) accounts for 55 to 99.95 weight % of the primer composition (A).
    Type: Grant
    Filed: October 28, 2014
    Date of Patent: June 13, 2017
    Assignee: KURARAY NORITAKE DENTAL INC.
    Inventors: Hirotaka Kita, Eiichi Terakawa, Mizuko Oshita
  • Publication number: 20170049665
    Abstract: Provided is a dental restorative composition that has good handling properties when in the form of a paste having yet to be cured and that has light diffusion ability and transparency when in the form of a cured product. The dental restorative composition includes a polymerizable monomer, a polymerization initiator, an inorganic filler (C) having an average particle diameter of 0.1 to 1 ?m, an organic-inorganic composite filler (D) having an average particle diameter of 1 ?m or more and less than 10 ?m, and an organic-inorganic composite filler (E) having an average particle diameter of 10 to 50 ?m. An absolute value of a difference between a refractive index (Cd) of the inorganic filler (C) and a refractive index (Ad) of a polymer of the polymerizable monomer is 0.01 or less, an absolute value of a difference between the refractive index (Ad) and one of a refractive index (Dd) of the organic-inorganic composite filler (D) and a refractive index (Ed) of the organic-inorganic composite filler (E) is 0.
    Type: Application
    Filed: February 17, 2015
    Publication date: February 23, 2017
    Applicant: KURARAY NORITAKE DENTAL INC.
    Inventors: Hirotaka KITA, Michiya KAWANA, Eiichi TERAKAWA
  • Publication number: 20160250107
    Abstract: The present invention provides a dental color tone adjustment material kit that has improved properties in terms of surface drying and of discoloration after curing and that enables adjustment to a desired color tone. The present invention relates to a dental color tone adjustment material kit including: a primer composition (A) including an acid group-containing polymerizable monomer (a) and a volatile organic solvent (b); and a dental color tone adjustment material B including a polymerizable monomer (d), a polymerization initiator (e), particle aggregates (f) that are chain aggregates of ultrafine filler particles having an average primary particle diameter of 1 to 50 nm, titanium dioxide (g), and a pigment (h). The monomer (a) accounts for 0.05 to 45 weight % of the primer composition (A), and the organic solvent (b) accounts for 55 to 99.95 weight % of the primer composition (A).
    Type: Application
    Filed: October 28, 2014
    Publication date: September 1, 2016
    Applicant: KURARAY NORITAKE DENTAL INC.
    Inventors: Hirotaka KITA, Eiichi TERAKAWA, Mizuko OSHITA
  • Patent number: 8476338
    Abstract: The present invention provides a dental curable composition exhibiting both excellent light diffusion and excellent transparency, and having high mechanical strength and surface smoothness and gloss after polishing as a cured product as well as good handling properties as a paste. The present invention is a dental curable composition including: a polymerizable monomer (A) having a refractive index of 1.52 to 1.58 after polymerization; inorganic particles (B) having a refractive index of 1.43 to 1.50; and inorganic particles (C) having a refractive index of 1.52 to 1.58. The inorganic particles (B) are aggregates of inorganic fine particles having an average primary particle size of 2 to 50 nm, and the content of the inorganic particles (B) is 0.1 to 10% by weight.
    Type: Grant
    Filed: December 10, 2010
    Date of Patent: July 2, 2013
    Assignee: Kuraray Noritake Dental Inc.
    Inventors: Masaki Okubayashi, Hirotaka Kita, Yusuke Takahata, Akiko Ota
  • Publication number: 20110257292
    Abstract: The present invention provides a dental curable composition exhibiting both excellent light diffusion and excellent transparency, and having high mechanical strength and surface smoothness and gloss after polishing as a cured product as well as good handling properties as a paste. The present invention is a dental curable composition including: a polymerizable monomer (A) having a refractive index of 1.52 to 1.58 after polymerization; inorganic particles (B) having a refractive index of 1.43 to 1.50; and inorganic particles (C) having a refractive index of 1.52 to 1.58. The inorganic particles (B) are aggregates of inorganic fine particles having an average primary particle size of 2 to 50 nm, and the content of the inorganic particles (B) is 0.1 to 10% by weight.
    Type: Application
    Filed: December 10, 2010
    Publication date: October 20, 2011
    Applicant: KURARAY MEDICAL INC.
    Inventors: Masaki Okubayashi, Hirotaka Kita, Yusuke Takahata, Akiko Ota
  • Publication number: 20090068123
    Abstract: The invention provides a fluoride ion releasing dental composition including an inorganic powder (a); a fluoride ion releasing material (b); a monomer (c); and a polymerization initiator (d), in which the inorganic powder (a) is made of composite particles in which a layer of polysiloxane is formed on surfaces of substrate particles made of an inorganic material, and the fluoride ion releasing material (b) is at least one fluoride ion releasing material selected from the group consisting of ammonium fluoride, ammonium hydrogen fluoride, a metal fluoride, a polymer including, as a constitutional unit, a vinyl monomer having an acid fluoride group and a fluorine-containing phosphazene monomer.
    Type: Application
    Filed: March 30, 2006
    Publication date: March 12, 2009
    Applicant: Kuraray Medical Inc
    Inventors: Mitsuru Takei, Hirotaka Kita, Yasujiro Ohara
  • Patent number: 6887920
    Abstract: The present invention provides a filler which has high water resistance and high acid resistance, and high releasing abilities of ions such as fluorine ions, and can maintain high aesthetic appreciation for a long period of time, and a dental composite material comprising the filler, excellent in water resistance, acid resistance, ion releasability and aesthetic appreciation.
    Type: Grant
    Filed: November 1, 2001
    Date of Patent: May 3, 2005
    Assignee: Kuraray Co., Ltd.
    Inventors: Junichi Ohtsuki, Hirotaka Kita, Koichi Okada, Yasujiro Ohara
  • Publication number: 20030060533
    Abstract: The present invention provides a filler which has high water resistance and high acid resistance, and high releasing abilities of ions such as fluorine ions, and can maintain high aesthetic appreciation for a long period of time, and a dental composite material comprising the filler, excellent in water resistance, acid resistance, ion releasability and aesthetic appreciation.
    Type: Application
    Filed: July 2, 2002
    Publication date: March 27, 2003
    Inventors: Junichi Ohtsuki, Hirotaka Kita, Koichi Okada, Yasujiro Ohara