Patents by Inventor Mitsuru Takei

Mitsuru Takei 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: 12249625
    Abstract: A silicon carbide semiconductor device has an active region and a termination structure portion disposed outside of the active region. The silicon carbide semiconductor device includes a semiconductor substrate of a second conductivity type, a first semiconductor layer of the second conductivity type, a second semiconductor layer of a first conductivity type, first semiconductor regions of the second conductivity type, second semiconductor regions of the first conductivity type, a gate insulating film, a gate electrode, a first electrode, and a second electrode. During bipolar operation, a smaller density among an electron density and a hole density of an end of the second semiconductor layer in the termination structure portion is at most 1×1015/cm3.
    Type: Grant
    Filed: November 30, 2021
    Date of Patent: March 11, 2025
    Assignees: FUJI ELECTRIC CO., LTD., MITSUBISHI ELECTRIC CORPORATION
    Inventors: Takeshi Tawara, Tomonori Mizushima, Shinichiro Matsunaga, Kensuke Takenaka, Manabu Takei, Hidekazu Tsuchida, Kouichi Murata, Akihiro Koyama, Koji Nakayama, Mitsuru Sometani, Yoshiyuki Yonezawa, Yuji Kiuchi
  • Publication number: 20240315930
    Abstract: The present invention provides a paste-form two-pack type dental curable composition having an adequate working time range and superior bond strength to dentin, in addition to showing small variation in working time, small decline in bond strength to dentin, and low risk of paste solidification over extended storage. The present invention relates to a paste-form two-pack type dental curable composition comprising: a first agent that comprises an acidic group-containing polymerizable monomer (A), an acidic group-free polymerizable monomer (B), an organic peroxide (C), a nitrogen atom-containing ligand (D), and a filler (E); and a second agent that comprises an acidic group-free polymerizable monomer (B), a thiourea compound (F), and a filler (E).
    Type: Application
    Filed: October 7, 2022
    Publication date: September 26, 2024
    Applicant: Kuraray Noritake Dental Inc.
    Inventors: Mitsuru TAKEI, Mariko KAWANA, Keishu OKADA
  • Publication number: 20240245584
    Abstract: The present invention provides a dental filling kit that exhibits good cavity sealing properties even when the cured product is subjected to repeated loads after cavities deeper than 2 mm, which normally require layered filling, are filled in bulk. The present invention relates to a dental filling kit comprising: a self-adhesive dental composite resin (X) that comprises a monomer (a) having an acidic group, a monomer (b) having no acidic group, a polymerization initiator (c), and a filler (d); and a dental composite resin (Y) that comprises a monomer (b) having no acidic group, a polymerization initiator (c), and a filler (d), but does not comprise a monomer (a) having an acidic group, wherein the polymerization initiator (c) contained in the dental composite resin (Y) comprises a photopolymerization initiator (c-1), and the dental composite resin (Y) is a bulk-fill composite resin, and has depth of cure of 4 mm or more.
    Type: Application
    Filed: April 26, 2022
    Publication date: July 25, 2024
    Applicant: Kuraray Noritake Dental Inc.
    Inventors: Ryo MATSUURA, Mitsuru TAKEI
  • Patent number: 11173100
    Abstract: The present invention provides a dental cement showing excellent storage stability, undergoing little change in paste properties during long-term storage, and having a small solidification risk during long-term storage. The present invention relates to a multi-part dental cement comprising: a first paste comprising an acid group-containing (meth)acrylic polymerizable monomer (a), a polyfunctional (meth)acrylic polymerizable monomer (b) containing no acid group, an oxidizing agent (c-1) of a chemical polymerization initiator, and a filler (d); and a second paste comprising a polyfunctional (meth)acrylic polymerizable monomer (b) containing no acid group, a reducing agent (c-2) of a chemical polymerization initiator, and a filler (e), wherein the filler (d) is treated with a surface treatment agent and has an average particle diameter of 0.01 to 50.
    Type: Grant
    Filed: October 20, 2017
    Date of Patent: November 16, 2021
    Assignee: KURARAY NORITAKE DENTAL INC.
    Inventors: Mariko Kawana, Shumei Ishihara, Mitsuru Takei, Kengo Futami
  • Patent number: 10987281
    Abstract: The present invention provides a self-adhesive dental composite resin maintaining mechanical strength, showing excellent storage stability, undergoing little change in transparency and properties of the paste during long-term storage, and having a small solidification risk during long-term storage. The present invention relates to a self-adhesive dental composite resin comprising: an acid group-containing (meth)acrylic polymerizable monomer (a); a polyfunctional (meth)acrylic polymerizable monomer (b) containing no acid group; a photopolymerization initiator (c); and a filler (d), wherein the filler (d) is treated with a surface treatment agent and has an average particle diameter of 0.01 to 50.0 ?m, the surface treatment agent comprises a silane coupling agent (A) represented by the following general formula (1): CH2?C(R1)—COO—(CH2)p—Si—R2qR3(3-q)??(1), and an organosilazane (B) represented by the following general formula (2): R4R5R6—Si—NH—Si—R7R8R9??(2).
    Type: Grant
    Filed: October 20, 2017
    Date of Patent: April 27, 2021
    Assignee: KURARAY NORITAKE DENTAL INC.
    Inventors: Shumei Ishihara, Yamato Nojiri, Mitsuru Takei, Kenji Hatanaka
  • Publication number: 20200179237
    Abstract: The present invention provides a self-adhesive dental composite resin maintaining mechanical strength, showing excellent storage stability, undergoing little change in transparency and properties of the paste during long-term storage, and having a small solidification risk during long-term storage. The present invention relates to a self-adhesive dental composite resin comprising: an acid group-containing (meth)acrylic polymerizable monomer (a); a polyfunctional (meth)acrylic polymerizable monomer (b) containing no acid group; a photopolymerization initiator (c); and a filler (d), wherein the filler (d) is treated with a surface treatment agent and has an average particle diameter of 0.01 to 50.0 ?m, the surface treatment agent comprises a silane coupling agent (A) represented by the following general formula (1): CH2?C(R1)—COO—(CH2)p—Si—R2qR3(3-q)??(1), and an organosilazane (B) represented by the following general formula (2): R4R5R6—Si—NH—Si—R7R8R9??(2).
    Type: Application
    Filed: October 20, 2017
    Publication date: June 11, 2020
    Applicant: KURARAY NORITAKE DENTAL INC.
    Inventors: Shumei ISHIHARA, Yamato NOJIRI, Mitsuru TAKEI, Kenji HATANAKA
  • Patent number: 10456333
    Abstract: Provided herein is a self-etching dental adhesive that exhibits excellent adhesiveness not only to dentin untreated by phosphoric acid etching, but to dentin treated by phosphoric acid etching. The present invention relates to a dental adhesive containing a (meth)acrylamide compound (a), an asymmetric acrylamide-methacrylic acid ester compound (b), and an acid group-containing (meth)acrylic polymerizable monomer (c). The (meth)acrylamide compound (a) is at least one selected from the group consisting of compounds represented by general formula (1), and compounds represented by general formula (2). The asymmetric acrylamide-methacrylic acid ester compound (b) is a compound represented by general formula (3). (In the formulae, the meanings of the symbols are omitted.
    Type: Grant
    Filed: December 6, 2016
    Date of Patent: October 29, 2019
    Assignee: KURARAY NORITAKE DENTAL INC.
    Inventors: Yamato Nojiri, Mitsuru Takei
  • Publication number: 20190262240
    Abstract: The present invention provides a dental cement showing excellent storage stability, undergoing little change in paste properties during long-term storage, and having a small solidification risk during long-term storage. The present invention relates to a multi-part dental cement comprising: a first paste comprising an acid group-containing (meth)acrylic polymerizable monomer (a), a polyfunctional (meth)acrylic polymerizable monomer (b) containing no acid group, an oxidizing agent (c-1) of a chemical polymerization initiator, and a filler (d); and a second paste comprising a polyfunctional (meth)acrylic polymerizable monomer (b) containing no acid group, a reducing agent (c-2) of a chemical polymerization initiator, and a filler (e), wherein the filler (d) is treated with a surface treatment agent and has an average particle diameter of 0.01 to 50.
    Type: Application
    Filed: October 20, 2017
    Publication date: August 29, 2019
    Applicant: KURARAY NORITAKE DENTAL INC.
    Inventors: Mariko KAWANA, Shumei ISHIHARA, Mitsuru TAKEI, Kengo FUTAMI
  • Patent number: 10231905
    Abstract: The present invention relates to providing a dental curable composition that, when cured, has high metal ion release ability and highly durable physical properties. The dental curable composition of the present invention includes: a sugar compound having an —XM group, where —X is an acid anion group and M is a metal cation; and a curable component.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: March 19, 2019
    Assignee: KURARAY NORITAKE DENTAL INC.
    Inventors: Mitsunobu Kawashima, Mitsuru Takei, Naoki Nishigaki, Shumei Ishihara, Kenji Hatanaka, Hiroshige Ishino, Akiko Tsuji
  • Publication number: 20180360696
    Abstract: Provided herein is a self-etching dental adhesive that exhibits excellent adhesiveness not only to dentin untreated by phosphoric acid etching, but to dentin treated by phosphoric acid etching. The present invention relates to a dental adhesive containing a (meth)acrylamide compound (a), an asymmetric acrylamide-methacrylic acid ester compound (b), and an acid group-containing (meth)acrylic polymerizable monomer (c). The (meth)acrylamide compound (a) is at least one selected from the group consisting of compounds represented by general formula (1), and compounds represented by general formula (2). The asymmetric acrylamide-methacrylic acid ester compound (b) is a compound represented by general formula (3). (In the formulae, the meanings of the symbols are omitted.
    Type: Application
    Filed: December 6, 2016
    Publication date: December 20, 2018
    Applicant: KURARAY NORITAKE DENTAL INC.
    Inventors: Yamato NOJIRI, Mitsuru TAKEI
  • Patent number: 10123947
    Abstract: The present invention provides a dental cement that exhibits excellent adhesiveness to dentin and has high mechanical strength. The present invention relates to a multi-part dental cement containing: an asymmetric acrylamide-methacrylic acid ester compound (a); an acid group-containing (meth)acrylic polymerizable monomer (b); a hydrophobic crosslinkable polymerizable monomer (c); a chemical polymerization initiator (d); and a filler (e). The asymmetric acrylamide-methacrylic acid ester compound (a) is represented by the following general formula (1): where X is an optionally substituted, linear or branched C1 to C6 aliphatic group or an optionally substituted aromatic group, the aliphatic group is optionally interrupted by at least one linking group selected from the group consisting of —O—, —S—, —CO—, —CO—O—, —O—CO—, —NR1—, —CO—NR1—, —NR1—CO—, —CO—O—NR1—, —O—CO—NR1—, and —NR1—CO—NR1—, and R1 is a hydrogen atom or an optionally substituted, linear or branched C1 to C6 aliphatic group.
    Type: Grant
    Filed: June 10, 2015
    Date of Patent: November 13, 2018
    Assignee: KURARAY NORITAKE DENTAL INC
    Inventors: Mitsuru Takei, Yamato Nojiri
  • Patent number: 10071028
    Abstract: The present invention provides a dental adhesive exhibiting excellent initial bond strength and bond durability to both enamel and dentin. The present invention relates to a dental adhesive containing: an asymmetric acrylamide-methacrylic acid ester compound (a); an acid group-containing (meth)acrylic polymerizable monomer (b); and a water-soluble polymerizable monomer (c). The asymmetric acrylamide-methacrylic acid ester compound (a) is represented by the following general formula (1): where X is an optionally substituted, linear or branched C1 to C6 aliphatic group or an optionally substituted aromatic group, the aliphatic group is optionally interrupted by at least one linking group selected from the group consisting of —O—, —S—, —CO—, —CO—O—, —O—CO—, —NR1—, —CO—NR1—, —NR1—CO—, —CO—O—NR1—, —O—CO—NR1—, and —NR1—CO—NR1—, and R1 is a hydrogen atom or an optionally substituted, linear or branched C1 to C6 aliphatic group.
    Type: Grant
    Filed: June 10, 2015
    Date of Patent: September 11, 2018
    Assignee: KURARAY NORITAKE DENTAL INC.
    Inventors: Yamato Nojiri, Mitsuru Takei
  • Patent number: 9844495
    Abstract: The present invention provides a self-adhesive composite resin having excellent adhesiveness to tooth structures and excellent mechanical strength. The present invention relates to a self-adhesive dental composite resin containing: an asymmetric acrylamide-methacrylic acid ester compound (a); an acid group-containing (meth)acrylic polymerizable monomer (b); a hydrophobic crosslinkable polymerizable monomer (c); a photopolymerization initiator (d); and a filler (e).
    Type: Grant
    Filed: June 10, 2015
    Date of Patent: December 19, 2017
    Assignee: KURARAY NORITAKE DENTAL INC.
    Inventors: Yasutaka Kudo, Yamato Nojiri, Mitsuru Takei
  • Publication number: 20170196778
    Abstract: The present invention provides a dental adhesive exhibiting excellent initial bond strength and bond durability to both enamel and dentin. The present invention relates to a dental adhesive containing: an asymmetric acrylamide-methacrylic acid ester compound (a); an acid group-containing (meth)acrylic polymerizable monomer (b); and a water-soluble polymerizable monomer (c). The asymmetric acrylamide-methacrylic acid ester compound (a) is represented by the following general formula (1): where X is an optionally substituted, linear or branched C1 to C6 aliphatic group or an optionally substituted aromatic group, the aliphatic group is optionally interrupted by at least one linking group selected from the group consisting of —O—, —S—, —CO—, —CO—O—, —O—CO—, —NR1—, —CO—NR1—, —NR1—CO—, —CO—O—NR1—, —O—CO—NR1—, and —NR1—CO—NR1—, and R1 is a hydrogen atom or an optionally substituted, linear or branched C1 to C6 aliphatic group.
    Type: Application
    Filed: June 10, 2015
    Publication date: July 13, 2017
    Applicant: KURARAY NORITAKE DENTAL INC.
    Inventors: Yamato NOJIRI, Mitsuru TAKEI
  • Patent number: 9700491
    Abstract: The present invention provides a one-part dental adhesive that exhibits excellent adhesive properties to both enamel and dentin and that has high storage stability and ambient-light stability. The present invention is a one-part dental adhesive including 1 to 30 weight % of a phosphoric acid group-containing monofunctional (meth)acrylate compound (a), 10 to 50 weight % of a water-soluble polymerizable monomer (b), 5 to 50 weight % of a hydrophobic crosslinkable (meth)acrylate compound (c), water (d), and a polymerization initiator (e). The water-soluble polymerizable monomer (b) includes a combination of a monofunctional (meth)acrylamide compound (b-1) having a particular structure and a water-soluble crosslinkable (meth)acrylic monomer (b-2). The weight ratio between the monofunctional (meth)acrylamide compound (b-1) and the water-soluble crosslinkable (meth)acrylic monomer (b-2) is 10:1 to 1:5.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: July 11, 2017
    Assignee: KURARAY NORITAKE DENTAL INC.
    Inventors: Mitsuru Takei, Yamato Nojiri
  • Publication number: 20170135909
    Abstract: The present invention provides a dental cement that exhibits excellent adhesiveness to dentin and has high mechanical strength. The present invention relates to a multi-part dental cement containing: an asymmetric acrylamide-methacrylic acid ester compound (a); an acid group-containing (meth)acrylic polymerizable monomer (b); a hydrophobic crosslinkable polymerizable monomer (c); a chemical polymerization initiator (d); and a filler (e). The asymmetric acrylamide-methacrylic acid ester compound (a) is represented by the following general formula (1): where X is an optionally substituted, linear or branched C1 to C6 aliphatic group or an optionally substituted aromatic group, the aliphatic group is optionally interrupted by at least one linking group selected from the group consisting of —O—, —S—, —CO—, —CO—O—, —O—CO—, —NR1—, —CO—NR1—, —NR1—CO—, —CO—O—NR1—, —O—CO—NR1—, and —NR1—CO—NR1—, and R1 is a hydrogen atom or an optionally substituted, linear or branched C1 to C6 aliphatic group.
    Type: Application
    Filed: June 10, 2015
    Publication date: May 18, 2017
    Applicant: KURARAY NORITAKE DENTAL INC.
    Inventors: Mitsuru TAKEI, Yamato NOJIRI
  • Publication number: 20170135910
    Abstract: The present invention provides a self-adhesive composite resin having excellent adhesiveness to tooth structures and excellent mechanical strength. The present invention relates to a self-adhesive dental composite resin containing: an asymmetric acrylamide-methacrylic acid ester compound (a); an acid group-containing (meth)acrylic polymerizable monomer (b); a hydrophobic crosslinkable polymerizable monomer (c); a photopolymerization initiator (d); and a filler (e).
    Type: Application
    Filed: June 10, 2015
    Publication date: May 18, 2017
    Applicant: KURARAY NORITAKE DENTAL INC.
    Inventors: Yasutaka KUDO, Yamato NOJIRI, Mitsuru TAKEI
  • Publication number: 20160038382
    Abstract: The present invention relates to providing a dental curable composition that, when cured, has high metal ion release ability and highly durable physical properties. The dental curable composition of the present invention includes: a sugar compound having an —XM group, where —X is an acid anion group and M is a metal cation; and a curable component.
    Type: Application
    Filed: March 25, 2014
    Publication date: February 11, 2016
    Applicant: KURARAY NORITAKE DENTAL INC.
    Inventors: Mitsunobu KAWASHIMA, Mitsuru TAKEI, Naoki NISHIGAKI, Shumei ISHIHARA, Kenji HATANAKA, Hiroshige ISHINO, Akiko TSUJI
  • Patent number: 9125802
    Abstract: The present invention provides a dental curable composition which has excellent curability and which cures into a cured product that is less susceptible to discoloration by hydrogen sulfide in an oral environment. The present invention is a dental curable composition containing: a polymerizable monomer (a) having an acidic group, as a polymerizable monomer component; and a copper compound (b) and a benzotriazole compound (c) represented by the following general formula (1) and/or a benzimidazole compound (c) represented by the following general formula (2), as polymerization initiator components (symbols used in the formulae are as described in the description).
    Type: Grant
    Filed: December 20, 2011
    Date of Patent: September 8, 2015
    Assignee: KURARAY NORITAKE DENTAL INC.
    Inventors: Mariko Sugiura, Mitsuru Takei
  • Publication number: 20150094392
    Abstract: The present invention provides a one-part dental adhesive that exhibits excellent adhesive properties to both enamel and dentin and that has high storage stability and ambient-light stability. The present invention is a one-part dental adhesive including 1 to 30 weight % of a phosphoric acid group-containing monofunctional (meth)acrylate compound (a), 10 to 50 weight % of a water-soluble polymerizable monomer (b), 5 to 50 weight % of a hydrophobic crosslinkable (meth)acrylate compound (c), water (d), and a polymerization initiator (e). The water-soluble polymerizable monomer (b) includes a combination of a monofunctional (meth)acrylamide compound (b-1) having a particular structure and a water-soluble crosslinkable (meth)acrylic monomer (b-2). The weight ratio between the monofunctional (meth)acrylamide compound (b-1) and the water-soluble crosslinkable (meth)acrylic monomer (b-2) is 10:1 to 1:5.
    Type: Application
    Filed: March 15, 2013
    Publication date: April 2, 2015
    Applicant: KURARAY NORITAKE DENTAL INC.
    Inventors: Mitsuru Takei, Yamato Nojiri