Patents by Inventor Chika YAMASHITA

Chika YAMASHITA 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: 10851199
    Abstract: An epoxy (meth)acrylate compound represented by general formula (1): where at least one of R1 to R5 has a structure represented by formula (2): * denotes the bonding position to a carbon atom that constitutes the benzene ring to which R1 to R5 are bonded in formula (1), R7 denotes a hydrogen atom or a methyl group, the remainder of R1 to R5 are each independently selected from the group consisting of hydrogen atoms, alkyl groups and alkoxy groups having 1-6 carbon atoms, and R6 denotes a hydrogen atom or a methyl group. In the epoxy (meth)acrylate compound, the content of halogen atoms is 100 ppm by mass or less. A curable composition for forming a protective film for an electrically conductive pattern obtained by mixing the epoxy (meth)acrylate compound with a photopolymerization initiator and at least one type of monomer or oligomer that contains a (meth)acryloyl group.
    Type: Grant
    Filed: July 24, 2017
    Date of Patent: December 1, 2020
    Assignee: SHOWA DENKO K. K.
    Inventors: Masahiko Toba, Jun Dou, Chika Yamashita, Yoshitaka Ishibashi, Hiroshi Uchida
  • Patent number: 10689493
    Abstract: A thermosetting resin composition includes a polyalkenyl phenol resin (A) and an aromatic polymaleimide compound (B). Polyalkenyl phenol resin (A) has at least one aromatic ring unit (a1) which may have a 2-alkenyl group bonded thereto and in which a phenolic hydroxyl group is alkyl-etherified, and at least one aromatic ring unit (a2) which has a phenolic hydroxyl group and which may have a 2-alkenyl group bonded thereto. At least one of aromatic ring units (a1, a2) has a 2-alkenyl group. Each aromatic ring unit is bonded by a linking group. When m represents the number of aromatic ring units (a1), and n represents the number of aromatic ring units (a2), n to (m+n) is 10-60%. The polyalkenyl phenol resin (A) is included in an amount at which the amount of 2-alkenyl groups becomes 0.4-1.5 mol per mol of maleimide groups in the aromatic polymaleimide compound (B).
    Type: Grant
    Filed: December 11, 2015
    Date of Patent: June 23, 2020
    Assignee: SHOWA DENKO K.K.
    Inventors: Hiromi Otake, Aoi Nakano, Chika Yamashita, Yoshitaka Ishibashi, Hiroshi Uchida
  • Publication number: 20190153149
    Abstract: [Problem] To provide an epoxy (meth)acrylate compound that serves as a material for a protective film that is unlikely to cause migration to an electrically conductive pattern, and a curable composition containing the epoxy (meth)acrylate compound. [Solution] Provided is an epoxy (meth)acrylate compound which is characterized by being represented by general formula (1) and in which the content of halogen atoms, which are impurities, is 100 ppm by mass or less. In addition, provided is a curable composition for forming a protective film for an electrically conductive pattern, the curable composition being obtained by mixing this epoxy (meth)acrylate compound with a photopolymerization initiator and at least one type of monomer or oligomer that contains a (meth)acryloyl group.
    Type: Application
    Filed: July 24, 2017
    Publication date: May 23, 2019
    Applicant: SHOWA DENKO K. K.
    Inventors: Masahiko TOBA, Jun DOU, Chika YAMASHITA, Yoshitaka ISHIBASHI, Hiroshi UCHIDA
  • Patent number: 10160737
    Abstract: A polyvalent glycidyl compound is produced from a compound having one or more 2-alkenyl ether groups and two or more 2-alkenyl groups using a hydrogen peroxide aqueous solution as an oxidizing agent to oxidize the 2-alkenyl ether groups and the 2-alkenyl groups. A 2-alkenyl ether compound having two or more (un)substituted 2-alkenyl groups and one or more (un)substituted 2-alkenyl ether groups is oxidized using a hydrogen peroxide aqueous solution as an oxidizing agent in the presence of a tungsten compound and a quaternary ammonium salt as catalysts and of phosphoric acid as a co-catalyst, while controlling the pH of the reaction solution to 1.0-4.0 using an acid other than phosphoric acid. During the oxidation, the step of adding the hydrogen peroxide aqueous solution to the reaction solution and the step of adding the acid other than phosphoric acid thereto are alternately repeated at intervals two or more times.
    Type: Grant
    Filed: October 28, 2015
    Date of Patent: December 25, 2018
    Assignee: SHOWA DENKO K.K.
    Inventors: Chika Yamashita, Yoshitaka Ishibashi
  • Patent number: 10160856
    Abstract: Provided is a thermosetting resin composition which exhibits excellent workability, and which is capable of obtaining, as a result of being cured, a highly reliable cured product (molded article) exhibiting excellent heat resistance and mechanical strength. This thermosetting resin composition includes: a polyalkenyl phenol resin (A); an aromatic polymaleimide compound (B); and a polymerization initiator (C). The polyalkenyl phenol resin (A) has, in a molecule thereof, at least one aromatic ring unit (a1) which has a phenolic hydroxyl group having a 2-alkenyl group bonded thereto, and at least one aromatic ring unit (a2) having a phenolic hydroxyl group which does not have a 2-alkenyl group bonded thereto. Each of the aromatic ring units is bonded by a linking group having a main chain which is not formed by an aromatic ring. When m represents the number of the aromatic ring units (a1), and n represents the number of the aromatic ring units (a2), the ratio of m to (m+n) is 40-90%.
    Type: Grant
    Filed: December 11, 2015
    Date of Patent: December 25, 2018
    Assignee: SHOWA DENKO K.K.
    Inventors: Hiromi Otake, Aoi Nakano, Chika Yamashita, Yoshitaka Ishibashi, Hiroshi Uchida
  • Publication number: 20180282494
    Abstract: Provided is a thermosetting resin composition which is capable of obtaining, as a result of being cured, a highly reliable cured product exhibiting excellent moisture resistance, heat resistance, and mechanical strength. The present invention includes a polyalkenyl phenol resin (A) and an aromatic polymaleimide compound (B). The polyalkenyl phenol resin (A) has, in a molecule thereof, at least one aromatic ring unit (a1) which has or does not have a 2-alkenyl group bonded thereto, and in which a phenolic hydroxyl group is alkyl-etherified, and at least one aromatic ring unit (a2) which has a phenolic hydroxyl group, and which has or does not have a 2-alkenyl group bonded thereto. At least one of the aromatic ring units (a1, a2) has a 2-alkenyl group. Each of the aromatic ring units is bonded by a linking group. When m represents the number of the aromatic ring units (a1), and n represents the number of the aromatic ring units (a2), the ratio of n to (m+n) is 10-60%.
    Type: Application
    Filed: December 11, 2015
    Publication date: October 4, 2018
    Applicant: SHOWA DENKO K.K.
    Inventors: Hiromi OTAKE, Aoi NAKANO, Chika YAMASHITA, Yoshitaka ISHIBASHI, Hiroshi UCHIDA
  • Publication number: 20170349743
    Abstract: Provided is a thermosetting resin composition which exhibits excellent workability, and which is capable of obtaining, as a result of being cured, a highly reliable cured product (molded article) exhibiting excellent heat resistance and mechanical strength. This thermosetting resin composition includes: a polyalkenyl phenol resin (A); an aromatic polymaleimide compound (B); and a polymerization initiator (C). The polyalkenyl phenol resin (A) has, in a molecule thereof, at least one aromatic ring unit (al) which has a phenolic hydroxyl group having a 2-alkenyl group bonded thereto, and at least one aromatic ring unit (a2) having a phenolic hydroxyl group which does not have a 2-alkenyl group bonded thereto. Each of the aromatic ring units is bonded by a linking group having a main chain which is not formed by an aromatic ring. When m represents the number of the aromatic ring units (a1), and n represents the number of the aromatic ring units (a2), the ratio of m to (m+n) is 40-90%.
    Type: Application
    Filed: December 11, 2015
    Publication date: December 7, 2017
    Applicant: SHOWA DENKO K.K.
    Inventors: Hiromi OTAKE, Aoi NAKANO, Chika YAMASHITA, Yoshitaka ISHIBASHI, Hiroshi UCHIDA
  • Publication number: 20170342042
    Abstract: A polyvalent glycidyl compound is produced from a compound having one or more 2-alkenyl ether groups and two or more 2-alkenyl groups using a hydrogen peroxide aqueous solution as an oxidizing agent to oxidize the 2-alkenyl ether groups and the 2-alkenyl groups. A 2-alkenyl ether compound having two or more (un)substituted 2-alkenyl groups and one or more (un)substituted 2-alkenyl ether groups is oxidized using a hydrogen peroxide aqueous solution as an oxidizing agent in the presence of a tungsten compound and a quaternary ammonium salt as catalysts and of phosphoric acid as a co-catalyst, while controlling the pH of the reaction solution to 1.0-4.0 using an acid other than phosphoric acid. During the oxidation, the step of adding the hydrogen peroxide aqueous solution to the reaction solution and the step of adding the acid other than phosphoric acid thereto are alternately repeated at intervals two or more times.
    Type: Application
    Filed: October 28, 2015
    Publication date: November 30, 2017
    Applicant: SHOWA DENKO K.K.
    Inventors: Chika YAMASHITA, Yoshitaka ISHIBASHI