Patents by Inventor Kazumichi NONAKA

Kazumichi NONAKA 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).

  • Publication number: 20230082975
    Abstract: [Problem] A technique for improving translucency in order to prepare a zirconia sintered body having high translucency without using special equipment, has been required. [Solution] To provide A sintering method for a dental zirconia calcined body containing 5.5 mol % to 7.0 mol % of a stabilizer, wherein the method satisfies the following (a) to (c). (a) an average rate of temperature increase in the section from room temperature to 1300° C. is 9° C./min or more. (b) an average rate of temperature increase in the section from 1300° C. to 1400° C. is 0.6° C./min or more and 3° C./min or less. (c) an average rate of temperature increase in the section from 1400° C. to the maximum temperature of the sintering process is 0.5° C./min or more and 2.5° C./min or less.
    Type: Application
    Filed: May 31, 2022
    Publication date: March 16, 2023
    Applicant: SHOFU INC.
    Inventors: Kazumichi NONAKA, Shuhei TAKAHASHI
  • Publication number: 20220202656
    Abstract: To provide a liquid for improving translucency for dental zirconia calcined body which may impart high translucency which is similar to an enamel of a natural tooth to a zirconia sintered body and a method for using thereof. The liquid for improving translucency for dental zirconia calcined body of the present disclosure contains a solvent and an indium compound, wherein a content of the indium compound based on the total amount of the liquid improving translucency for dental zirconia calcined body is within a range of 2.0 wt. % to 20.0 wt. % in terms of indium.
    Type: Application
    Filed: October 15, 2021
    Publication date: June 30, 2022
    Applicant: SHOFU INC.
    Inventors: Kazumichi NONAKA, Shuhei TAKAHASHI
  • Publication number: 20220202544
    Abstract: [Problem] A technique for imparting high translucency which is similar to an enamel of a natural tooth to a zirconia sintered body, has been required. [Solution] To provide a zirconia mill blank for dental cutting and machining, containing, an yttrium compound and an indium compound as stabilizers, wherein, an amount of the yttrium compound is within a range of 3.0 mol % to 6.0 mol % in terms of oxide, an amount of the indium compound is within a range of 0.2 mol % to 3.0 mol % in terms of oxide, and a total amount of the yttrium compound and the indium compound is within a range of 5.5 mol % to 7.0 mol % in terms of oxide.
    Type: Application
    Filed: October 15, 2021
    Publication date: June 30, 2022
    Applicant: SHOFU INC.
    Inventors: Kazumichi NONAKA, Shuhei TAKAHASHI
  • Publication number: 20210401552
    Abstract: [Problem] To provide a zirconia mill blank for dental cutting and machining which may impart reproducibility of color tone similar to a natural tooth and high strength to a zirconia perfect sintered body without a special sintering method such as HIP treatment. [Solution] A zirconia mill blank for dental cutting and machining comprises at least two intermediate layers LA and LB which satisfy the following Formula (1) and Formula (2), wherein the layer LA is contained in a section A in which a distance from one plane of two planes is within 40% of the distance between the two planes and the layer LB is contained in a section B in which a distance from the other plane is within 40% of the distance between the two planes, wherein in a case in which, a sintered body prepared by sintering at 1550° C. a test specimen cut out from the layer LA is defined as sintered body SA, a sintered body at 1550° C.
    Type: Application
    Filed: March 5, 2021
    Publication date: December 30, 2021
    Applicant: SHOFU INC.
    Inventors: Kazumichi NONAKA, Shuhei TAKAHASHI, Mitsuji TERAMAE
  • Publication number: 20210401553
    Abstract: [Problem] To support the metal without segregation on the zirconia mill blank for dental cutting and machining which has been adjusted to a hardness that enables to cut and machine by calcining at a low temperature. [Solution] A zirconia mill blank for dental cutting and machining is prepared by A preparing method of a zirconia mill blank for dental cutting and machining, comprising an impregnation step of impregnating a porous zirconia molded body with an impregnating solution containing at least one metal ion and at least one precipitant, and a deposition step of decomposing the precipitant in the porous zirconia molded body to deposit a metal compound.
    Type: Application
    Filed: March 22, 2021
    Publication date: December 30, 2021
    Applicant: SHOFU INC.
    Inventors: Kazumichi NONAKA, Shuhei TAKAHASHI
  • Publication number: 20200331807
    Abstract: An object of the present disclosure is to provide a zirconia mill blank for dental cutting and machining which may impart high translucency similar to an enamel of a natural tooth to zirconia sintered body even in a short time sintering, and a preparing method thereof. In addition, the present disclosure provides a zirconia mill blank for dental cutting and machining which may impart the same degree of translucency to a zirconia sintered body even in a short time sintering as compared with the case of sintering for 427 minutes. The zirconia mill blank for dental cutting and machining of the present disclosure contains a gallium compound.
    Type: Application
    Filed: January 21, 2020
    Publication date: October 22, 2020
    Applicant: SHOFU INC.
    Inventors: Kazumichi NONAKA, Shuhei TAKAHASHI
  • Publication number: 20200170753
    Abstract: To provide a zirconia mill blank for dental cutting and machining which has excellent machinability in a thin workpiece such as an inlay, an onlay and a veneer, and may impart high strength and high translucency to a zirconia perfect sintered body without a special sintering such as HIP treatment, and a preparing method thereof. The zirconia mill blank for dental cutting and machining has a porosity within a range of 15 to 30%.
    Type: Application
    Filed: August 21, 2019
    Publication date: June 4, 2020
    Applicant: SHOFU INC.
    Inventors: Kazumichi NONAKA, Shuhei TAKAHASHI