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).
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Publication number: 20210284783Abstract: Provided are a curable resin mixture and a curable resin composition which contain a polyalkenylphenol resin and an aromatic polymaleimide compound having high crystallinity and a high melting point, and which exhibit excellent fluidity and reactivity. Also provided is a method for producing a curable resin mixture that contains: (A) a polyalkenylphenol resin which contains a polyalkenylphenol compound having at least 2 phenol skeletons in the molecule, a prescribed 2-alkenyl group being bonded to some or all of aromatic rings that form the phenol skeletons in the molecule; and (B) an aromatic polymaleimide compound. The method comprises: heating the aromatic polymaleimide compound (B) to the melting point or above and thereby melting the compound; and mixing the molten aromatic polymaleimide compound (B) and the polyalkenylphenol resin (A) within a temperature range at which the aromatic polymaleimide compound (B) does not recrystallize.Type: ApplicationFiled: May 25, 2017Publication date: September 16, 2021Applicant: SHOWA DENKO K.K.Inventors: Aoi HASEGAWA, Chika YAMASHITA, Yoshitaka ISHIBASHI, Tomonori TAJIMA, Hiromi OTAKE
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Patent number: 10851199Abstract: 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: GrantFiled: July 24, 2017Date of Patent: December 1, 2020Assignee: SHOWA DENKO K. K.Inventors: Masahiko Toba, Jun Dou, Chika Yamashita, Yoshitaka Ishibashi, Hiroshi Uchida
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Patent number: 10689493Abstract: 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: GrantFiled: December 11, 2015Date of Patent: June 23, 2020Assignee: SHOWA DENKO K.K.Inventors: Hiromi Otake, Aoi Nakano, Chika Yamashita, Yoshitaka Ishibashi, Hiroshi Uchida
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Publication number: 20190153149Abstract: [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: ApplicationFiled: July 24, 2017Publication date: May 23, 2019Applicant: SHOWA DENKO K. K.Inventors: Masahiko TOBA, Jun DOU, Chika YAMASHITA, Yoshitaka ISHIBASHI, Hiroshi UCHIDA
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Patent number: 10160856Abstract: 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: GrantFiled: December 11, 2015Date of Patent: December 25, 2018Assignee: SHOWA DENKO K.K.Inventors: Hiromi Otake, Aoi Nakano, Chika Yamashita, Yoshitaka Ishibashi, Hiroshi Uchida
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Patent number: 10160737Abstract: 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: GrantFiled: October 28, 2015Date of Patent: December 25, 2018Assignee: SHOWA DENKO K.K.Inventors: Chika Yamashita, Yoshitaka Ishibashi
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Publication number: 20180282494Abstract: 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: ApplicationFiled: December 11, 2015Publication date: October 4, 2018Applicant: SHOWA DENKO K.K.Inventors: Hiromi OTAKE, Aoi NAKANO, Chika YAMASHITA, Yoshitaka ISHIBASHI, Hiroshi UCHIDA
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Publication number: 20170349743Abstract: 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: ApplicationFiled: December 11, 2015Publication date: December 7, 2017Applicant: SHOWA DENKO K.K.Inventors: Hiromi OTAKE, Aoi NAKANO, Chika YAMASHITA, Yoshitaka ISHIBASHI, Hiroshi UCHIDA
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Publication number: 20170342042Abstract: 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: ApplicationFiled: October 28, 2015Publication date: November 30, 2017Applicant: SHOWA DENKO K.K.Inventors: Chika YAMASHITA, Yoshitaka ISHIBASHI