Patents Assigned to Tokuyama Dental Corporation
  • Patent number: 11098138
    Abstract: A photopolymerization initiator including (a) a photosensitizer, (b) a tertiary amine compound and (c) an aryliodonium salt wherein, as the aryliodonium salt (c), there is selected the one that generates an acid having a dissociation constant of not less than ?3.0 in water of 25° C.
    Type: Grant
    Filed: March 8, 2017
    Date of Patent: August 24, 2021
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Koji Furuhashi, Hironobu Akizumi
  • Patent number: 11078303
    Abstract: Provided is a curable composition containing a polymerizable monomer (A), an organic-inorganic composite filler (B), and a polymerization initiator (C), wherein the organic-inorganic composite filler (B) includes an organic resin matrix (b1) and a spherical inorganic filler (b2) having an average primary particle size of 230-1000 nm, 90% or more of the number of individual particles constituting the spherical inorganic filler (b2) are present in a range of 5% greater or less than the average primary particle size, and the curable composition satisfies the following formulas (1) and (2): nP<nFb2??(formula 1) and nMb1<nFb2??(formula 2) In the formulas, nP represents the refractive index of the polymer of the polymerizable monomer (A) at 25° C., nFb2 represents the refractive index of the spherical inorganic filler (b2) at 25° C., and nMb1 represents the refractive index of the organic resin matrix (b1) at 25° C.
    Type: Grant
    Filed: November 28, 2017
    Date of Patent: August 3, 2021
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Hironobu Akizumi, Takuma Matsuo
  • Patent number: 11065183
    Abstract: Provided is a curable composition comprising a polymerizable monomer (A); spherical particles (B) having an average primary-particle diameter in a range of 230 nm to 1,000 nm; and a polymerization initiator (C), in which 90% or more of individual particles constituting the spherical particles (B) lies in a range of ±5% based on the average primary-particle diameter, and the refractive index of the spherical particles (B) is larger than the refractive index of a polymer of the polymerizable monomer (A). When a 1 mm-thick cured product is formed from the curable composition and the Y value (Yb) of the colored light of the cured product on a black background and the Y value (Yw) of the colored light of the cured product on a white background are each measured using a color difference meter, the ratio therebetween, Yb/Yw, being within a range of 0.2 to 0.5.
    Type: Grant
    Filed: April 16, 2018
    Date of Patent: July 20, 2021
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Takuma Matsuo, Hironobu Akizumi
  • Patent number: 11058608
    Abstract: Provided is a method for producing a dental curable composition, the method includes mixing a polymerizable monomer (A); a spherical filler (B) having an average primary particle diameter within a range of 230 nm to 290 nm; a spherical filler (C) having an average primary particle diameter within a range of 100 nm to 500 nm, the spherical filler having an average primary particle diameter different from that of the spherical filler (B); and a polymerization initiator (D), in which 90% or more in number of the individual particles constituting the spherical filler (B) and the spherical filler (C) are present in a range of ±5% from the average primary particle diameter, and the refractive indices of the spherical filler (B) and the spherical filler (C) are larger than the refractive index of a polymer of a polymerizable monomer (A).
    Type: Grant
    Filed: April 16, 2018
    Date of Patent: July 13, 2021
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Hiroshi Morisaki, Hironobu Akizumi
  • Publication number: 20210196440
    Abstract: The present invention provides a photopolymerization device having: a polymerization container; and a body part which is thermally connected to the polymerization container and which is formed by including a light source for applying light to the inside of the polymerization container. The photopolymerization device is characterized by being configured such that heat generated from the light source is guided to the polymerization container side.
    Type: Application
    Filed: February 28, 2018
    Publication date: July 1, 2021
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Tatsuya YAMAZAKI, Hideki KAZAMA
  • Publication number: 20210188634
    Abstract: A method for producing a weakly acidic hypochlorous acid aqueous solution comprises (A) an ion-exchange step for generating molecular hypochlorous acid dissolved in a mixed solution by mixing a raw material aqueous solution composed of an aqueous solution of a metal salt of hypochlorous acid with an acidic ion-exchange resin to perform ion exchange between the metal ions and the hydrogen ions, and (B) a separation step for separating the acidic ion-exchange resin from the mixed solution after the ion-exchange step and obtaining weakly acidic hypochlorous acid aqueous solution in which molecular hypochlorous acid is dissolved.
    Type: Application
    Filed: May 21, 2019
    Publication date: June 24, 2021
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Ayumi TAKAHASHI, Eibu SAKATA, Kouichirou HIRATA, Hideki KAZAMA
  • Publication number: 20210137652
    Abstract: Provided is a reference denture alignment jig which guides reference dentures into an oral cavity or to an articulator in which upper and lower edentulous jaw models are fixed, and aligns the reference dentures in the oral cavity or in the articulator in which upper and lower edentulous jaw models are fixed, the jig having a reference denture holding portion for holding reference dentures.
    Type: Application
    Filed: May 10, 2018
    Publication date: May 13, 2021
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Tatsuya YAMAZAKI, Kei NAKASHIMA, Youichi YAMAMOTO, Hitoshi MOTOHASHI
  • Patent number: 11001713
    Abstract: Disclosed is an organic/inorganic composite filler that contains: inorganic agglomerated particles comprising agglomerations of inorganic primary particles having a mean diameter between 10 and 1000 nm; an organic resin phase that covers the surface of each inorganic primary particle and binds the inorganic primary particles to each other; and intra-agglomerate voids, formed between the organic resin phase covering the surface of each inorganic primary particle, with a pore volume (here, “pore” refers to holes with diameters between 1 and 500 nm) between 0.01 and 0.30 cm3/g as measured by mercury intrusion porosimetry. Also disclosed is a method for manufacturing the above organic/inorganic composite filler.
    Type: Grant
    Filed: May 29, 2018
    Date of Patent: May 11, 2021
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Tatsuya Yamazaki, Hironobu Akizumi
  • Patent number: 10973740
    Abstract: The present invention provides a powder-liquid type denture base liner comprising: a powder material including (A) uncrosslinked resin particles, (B) an organic peroxide, (C) a pyrimidine trione derivative, and (D) an organic metal compound; and a liquid material including (E) a radical polymerizable monomer and (F) an aromatic amine compound, wherein the powder-liquid denture base liner is characterized in that the (C) pyrimidine trione derivative is 0.0002-1.0 mass parts per 100 mass parts of (E) radical polymerizable monomer.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: April 13, 2021
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Miki Hitomi, Ayumu Gyakushi, Kei Nakashima
  • Publication number: 20210095113
    Abstract: A resin block suitable for dental cutting work may include a resin matrix (A) and spherical filler (B) whose average particle size ranges from 230 to 1000 nm. When 10 mm thick and measured with a colorimeter, the lightness (V) is less than 5.0 and the saturation (C) is less than 2.0 in a Munsell color system of colored light on a black background and a white background. When 1 mm thick, the lightness (V) is less than 5.0 and the saturation (C) is 0.05 or more on a black background, but on a white background, the lightness (V) is 6.0 or more and the saturation (C) is less than 2.0 for Munsell colored light. Resin blocks can be used for dental restoration such that dental prostheses produced from the block not using a pigment/dye are compatible with natural teeth color tone, and the color tone compatibility endures.
    Type: Application
    Filed: March 28, 2019
    Publication date: April 1, 2021
    Applicant: Tokuyama Dental Corporation
    Inventors: Takuma MATSUO, Hironobu AKIZUMI
  • Patent number: 10828240
    Abstract: A photocurable composition is provided, which is characterized by comprising a polymerizable monomer component (A), an inorganic filler component (B) having an average particle diameter of 0.07 ?m or more, an organic-inorganic composite filler component (C) comprising an inorganic filler component (C1) and an organic polymer component (C2) and having an average particle diameter of 0.5 ?m or more, and a photopolymerization initiator (D), wherein the inorganic filler component (B) and the organic-inorganic composite filler component (C) are contained in a total amount of 100 to 1500 parts by mass relative to 100 parts by mass of the polymerizable monomer component (A), and the polymerizable monomer component (A), 90 parts by mass or more of the inorganic filler component (B) and 90 parts by mass or more of the organic-inorganic composite filler component (C) are selected in such a manner that specific requirements can be satisfied.
    Type: Grant
    Filed: August 30, 2017
    Date of Patent: November 10, 2020
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Keishi Fukudome, Hironobu Akizumi
  • Patent number: 10813850
    Abstract: A dental resin composite material is provided that is reduced in darkness of its color tone, and also reduced in burning and color unevenness. Specifically provided are a dental resin composite material including 100 parts by mass of a polyaryletherketone resin, 10 parts by mass to 300 parts by mass of inorganic particles, and 90 ppm or less of an impurity having an aromatic ring, a method of producing the dental resin composite material, and a polyaryletherketone resin for producing a dental resin composite material, to be used for producing the dental resin composite material.
    Type: Grant
    Filed: October 12, 2017
    Date of Patent: October 27, 2020
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Junichiro Yamagawa, Tomonao Shimizu, Yuko Nagasawa, Anna Uehara
  • Publication number: 20200330333
    Abstract: The dental restorative material of the present invention is a dental restorative material that contains a resin matrix and an inorganic filler in an amount of 25 to 1,000 parts by mass per 100 parts by mass of the resin matrix, and in the dental restorative material, the resin matrix contains a polyurethane resin, and the inorganic filler has an average particle diameter of 0.001 to 100 ?m. According to the present invention, a dental restorative material that has a high bending strength and a high surface hardness, and is excellent in transparency and cutting workability, and a resin material for dental cutting work containing the same can be provided.
    Type: Application
    Filed: December 26, 2018
    Publication date: October 22, 2020
    Applicant: Tokuyama Dental Corporation
    Inventors: Takuya SUZUKI, Hideki KAZAMA
  • Patent number: 10758457
    Abstract: Provided is a curable composition including a polymerizable monomer component (A), a spherical filler (B) having an average particle size within the range of 230-1000 nm, and a polymerization initiator (C), wherein the curable composition is characterized by having a value (V) of less than 5 and a chroma (C) of 0.05 or higher in colorimetric values according to the Munsell Color System in colored light on a black background, and a value (V) of 6 or higher and a chroma (C) of less than 2 in colorimetric values according to the Munsell Color System in colored light on a white background, each of the values (V) and chroma (C) being measured using a color difference meter in a state in which a 1-mm-thick cured article has been formed.
    Type: Grant
    Filed: October 21, 2016
    Date of Patent: September 1, 2020
    Assignee: TOKUYAMA DENTAL CORPORATION
    Inventors: Hironobu Akizumi, Chika Toriyabe
  • Patent number: 10639131
    Abstract: A resin block that can be favorably used for obtaining dental prosthetics through the milling work, containing very little voids, having excellent property for being cut, exhibiting excellent appearance and mechanical strength, and without permitting the formation of defective products. The resin block contains a thermoplastic resin having a fluidizing temperature in a range of 310 to 500° C. and inorganic particles in an amount of 30 to 150 parts by mass per 100 parts by mass of said thermoplastic resin. The inorganic particles are at least one kind of inorganic oxide particles selected from the group consisting of silica particles, silica composite particles of silica and other metal oxides, titania particles, and titania composite particles of titania and other metal oxides. The resin block has a thick portion of a thickness of at least not less than 5 mm, and does not contain any void whose length is not less than 1.0 mm.
    Type: Grant
    Filed: October 25, 2016
    Date of Patent: May 5, 2020
    Assignee: Tokuyama Dental Corporation
    Inventors: Junichiro Yamagawa, Tomonao Shimizu, Yuko Nagasawa
  • Publication number: 20200129384
    Abstract: Provided is a method for producing a dental curable composition, the method includes mixing a polymerizable monomer (A); a spherical filler (B) having an average primary particle diameter within a range of 230 nm to 290 nm; a spherical filler (C) having an average primary particle diameter within a range of 100 nm to 500 nm, the spherical filler having an average primary particle diameter different from that of the spherical filler (B); and a polymerization initiator (D), in which 90% or more in number of the individual particles constituting the spherical filler (B) and the spherical filler (C) are present in a range of ±5% from the average primary particle diameter, and the refractive indices of the spherical filler (B) and the spherical filler (C) are larger than the refractive index of a polymer of a polymerizable monomer (A).
    Type: Application
    Filed: April 16, 2018
    Publication date: April 30, 2020
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Hiroshi Morisaki, Hironobu Akizumi
  • Publication number: 20200121564
    Abstract: Provided is a curable composition comprising a polymerizable monomer (A); spherical particles (B) having an average primary-particle diameter in a range of 230 nm to 1,000 nm; and a polymerization initiator (C), in which 90% or more of individual particles constituting the spherical particles (B) lies in a range of ±5% based on the average primary-particle diameter, and the refractive index of the spherical particles (B) is larger than the refractive index of a polymer of the polymerizable monomer (A). When a 1 mm-thick cured product is formed from the curable composition and the Y value (Yb) of the colored light of the cured product on a black background and the Y value (Yw) of the colored light of the cured product on a white background are each measured using a color difference meter, the ratio therebetween, Yb/Yw, being within a range of 0.2 to 0.5.
    Type: Application
    Filed: April 16, 2018
    Publication date: April 23, 2020
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Takuma Matsuo, Hironobu Akizumi
  • Publication number: 20200069534
    Abstract: Provided is a photocurable composition that contains a polymerizable monomer (A), a spherical filler (B) having an average particle size within the range of 230-1000 nm, and a polymerization initiator (C), the photocurable composition being such that: 90% or more of the individual particles that constitute the spherical filler (B) are within a range of ±5% of the average particle size; the polymerizable monomer (A) and the spherical filler (B) satisfy condition (X1) represented by formula (1): nP<nF (where nP represents the refractive index at 25° C. of a polymer obtained by polymerizing the polymerizable monomer (A) and nF represents the refractive index at 25° C. of the spherical filler (B)); and the polymerization initiator (C) includes a photosensitizing compound (C1), a tertiary amine compound (C2), and a photoacid generator (C3).
    Type: Application
    Filed: March 5, 2018
    Publication date: March 5, 2020
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Koji Furuhashi, Hironobu Akizumi
  • Publication number: 20190292278
    Abstract: Provided is a curable composition containing a polymerizable monomer (A), an organic-inorganic composite filler (B), and a polymerization initiator (C), wherein the organic-inorganic composite filler (B) includes an organic resin matrix (b1) and a spherical inorganic filler (b2) having an average primary particle size of 230-1000 nm, 90% or more of the number of individual particles constituting the spherical inorganic filler (b2) are present in a range of 5% greater or less than the average primary particle size, and the curable composition satisfies the following formulas (1) and (2): nP<nFb2??(formula 1) and nMb1<nFb2??(formula 2) In the formulas, nP represents the refractive index of the polymer of the polymerizable monomer (A) at 25° C., nFb2 represents the refractive index of the spherical inorganic filler (b2) at 25° C., and nMb1 represents the refractive index of the organic resin matrix (b1) at 25° C.
    Type: Application
    Filed: November 28, 2017
    Publication date: September 26, 2019
    Applicant: TOKUYAMA DENTAL CORPORATION
    Inventors: Hironobu Akizumi, Takuma Matsuo
  • Patent number: D897539
    Type: Grant
    Filed: January 4, 2019
    Date of Patent: September 29, 2020
    Assignee: Tokuyama Dental Corporation
    Inventors: Tatsuya Yamazaki, Kei Nakashima, Youichi Yamamoto, Hitoshi Motohashi