Patents by Inventor Nobumasa Ohtake

Nobumasa Ohtake 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: 7994769
    Abstract: Multiple switching transistors are provided in parallel. An output circuit includes an inductor, an output capacitor, and a rectifying device. A pulse modulator generates a pulse signal with the duty ratio adjusted such that the output voltage of a switching regulator approaches a predetermined target value. A driver distributes a pulse signal to the multiple switching transistors, and switches the multiple switching transistors to the ON state in a time divisional manner.
    Type: Grant
    Filed: November 26, 2008
    Date of Patent: August 9, 2011
    Assignee: Rohm Co., Ltd.
    Inventors: Nobumasa Ohtake, Nobuaki Umeki
  • Publication number: 20100109625
    Abstract: Multiple switching transistors are provided in parallel. An output circuit includes an inductor, an output capacitor, and a rectifying device. A pulse modulator generates a pulse signal with the duty ratio adjusted such that the output voltage of a switching regulator approaches a predetermined target value. A driver distributes a pulse signal to the multiple switching transistors, and switches the multiple switching transistors to the ON state in a time divisional manner.
    Type: Application
    Filed: November 26, 2008
    Publication date: May 6, 2010
    Applicant: ROHM CO., LTD.
    Inventors: Nobumasa OHTAKE, Nobuaki UMEKI
  • Patent number: 5140087
    Abstract: The present invention relates to an organosiloxane compound suitable for the modification of silicone rubbers and synthetic resins, an organosiloxane compound useful as its intermediate, and a process for preparing them. The organosiloxane compound of the present invention can be represented by the general formula (IV) ##STR1## wherein j is an integer of 1 to 2000, R is an alkyl group having 1 to 4 carbon atoms, and R.sup.1 is a pentafluorophenyl group or a straight-chain or a branched fluoroalkyl group represented by the formula (II)C.sub.a H.sub.b F.sub.2a-b+1 (II)wherein a is an integer of 3 to 18, and b is an integer of 0 to 2a.The siloxane compounds of the present invention also include compounds having siloxane chains, at least one of the chains having a substituent with a fluorine atom containing group at the terminal thereof.
    Type: Grant
    Filed: October 30, 1990
    Date of Patent: August 18, 1992
    Assignee: Chisso Corporation
    Inventors: Takahiro Saho, Yoshinori Akutsu, Takaharu Nakano, Nobumasa Ohtake
  • Patent number: 5098981
    Abstract: A novel polyorganosiloxane is provided which has a fluorine atom-containing substituent at one terminal of its molecular chain and an unsaturated double bond-containing substituent at the other terminal thereof. The polyorgansiloxane of the present invention is represented by the general formula (I) ##STR1## wherein j is an integer of 1 to 2000, and R.sup.1 is an unsaturated double bond-containing group, each of R.sup.2 and R.sup.3 is an alkyl group having 1 to 4 carbon atoms, phenyl group, vinyl group, straight-chain or branched alkenyl group having 3 to 20 carbon atoms, or a siloxane chain which is similar to ##STR2## and R.sup.4 is a fluorine atom-containing substituent, ##STR3## wherein R.sup.10 is similar to R.sup.4 and is the fruorine atom-containing substituent, R.sup.
    Type: Grant
    Filed: February 7, 1991
    Date of Patent: March 24, 1992
    Assignee: Chisso Corporation
    Inventors: Takahiro Saho, Yoshinori Akutsu, Takaharu Nakano, Nobumasa Ohtake
  • Patent number: 5096990
    Abstract: Resin compositions for the inner coat of semiconductors which include(A) 100 parts by weight of a polysiloxane having vinyl groups and having a viscosity of 100 to 800cP at 25.degree. C., said polysiloxane having a general formula ##STR1## in which V represents a vinyl group, Me represents a methyl group, Ph represents a phenyl group, R represents a methyl group or a phenyl group and both k and l represent natural numbers which are variables within the range of 0.01.ltoreq.l/(k+l).ltoreq.0.2,(B) 1 to 35 parts by weight of a polysiloxane haivng a viscosity of 2 to 500cP at 25.degree. C., said polysiloxane having a general formula ##STR2## in which Me represents a methyl group, and both m and n represent natural numbers which are variables within the range of 0.05.ltoreq.n/(M+n).ltoreq.0.3,(C) 0.
    Type: Grant
    Filed: October 19, 1989
    Date of Patent: March 17, 1992
    Assignees: Tomoegawa Paper Co., Ltd., Chisso Corporation
    Inventors: Kazuhiro Takayanagi, Masayuki Tsuchida, Atsushi Koshimura, Nobumasa Ohtake, Tamio Kimura
  • Patent number: 5047491
    Abstract: A polyorganosiloxane compound is provided which has a fluorine-containing group at its .alpha.-position and one or more than one hydrosilyl group at its .omega.-position, has a fluorine-containing group located at least at its .alpha.- and .alpha.'-position and one or more than one hydrosilyl group at its .omega.-position or has a fluorine-containing group at least at its .alpha.-, .alpha.'- and .alpha."-position and one or more than one hydrosilyl group at its .omega.-position.
    Type: Grant
    Filed: August 1, 1989
    Date of Patent: September 10, 1991
    Assignee: Chisso Corporation
    Inventors: Takahiro Saho, Yoshinori Akutsu, Takaharu Nakano, Nobumasa Ohtake
  • Patent number: 4996280
    Abstract: A polyorganosiloxane compound which has a fluorine-containing group at its one terminal and an aminopropyl group at its other terminal.The polyorganosiloxane compound can provide various improved properties as well as new properties to synthetic resins by a chemical connection to the synthetic resins with a functional group or groups reactive with the amino group at the other terminal thereof.
    Type: Grant
    Filed: August 1, 1989
    Date of Patent: February 26, 1991
    Assignee: Chisso Corporation
    Inventors: Takahiro Saho, Yoshinori Akutsu, Takaharu Nakano, Nobumasa Ohtake
  • Patent number: 4992521
    Abstract: The present invention relates to an organosiloxane compound suitable for the modification of silicone rubbers and synthetic resins, an organosiloxane compound useful as its intermediate, and a process for preparing them. The organosiloxane compound of the present invention can be represented by the general formula (IV) ##STR1## wherein j is an integer of 1 to 2000, R is an alkyl group having 1 to 4 carbon atoms, and R.sup.1 is a pentafluorophenyl group or a straight-chain or a branched fluoroalkyl group represented by the formula (III)C.sub.1 H.sub.b F.sub.2a-b+1 (II)wherein a is an integer of 3 to 18, and b is an integer of 0 to 2a.The siloxane compound of the present invention has a siloxane chain each having a substituent with a fluorine atom containing group at the terminal thereof. Each of molecules constituting the polysiloxane compound of the present invention has a terminal hydrosilyl group portion and a fluorine atom-containing terminal substituent portion therein.
    Type: Grant
    Filed: April 21, 1989
    Date of Patent: February 12, 1991
    Assignee: Chisso Corporation
    Inventors: Takahiro Saho, Yoshinori Akutsu, Takaharu Nakano, Nobumasa Ohtake
  • Patent number: 4987203
    Abstract: A polyorganosiloxane compound contains a fluorine-containing substituent at least at its .alpha.-, .alpha.'- or .alpha."-position and a substituent having an epoxy linkage at its .omega.-position. The polyorganosiloxane compound can provide a synthetic resin with properties which cannot be provided by conventional polysiloxane compound by incorporating the polyorganosiloxane compound into the synthetic resin through a chemical linkage via the epoxy linkage thereof and a group reactive with the epoxy linkage thereof.
    Type: Grant
    Filed: October 24, 1989
    Date of Patent: January 22, 1991
    Assignee: Chisso Corporation
    Inventors: Takahiro Saho, Yoshinori Akutsu, Takaharu Nakano, Nobumasa Ohtake
  • Patent number: 4839443
    Abstract: A polysiloxane compound modified with two hydroxyl groups at the one end thereof and particularly suitable for improving the surface characteristics of resins prepared by polycondensation of a polyol with another polyfunctional compound, and a silicone-modified polyurethane having superior characteristics such as low frictional properties, water repellency, oil repellency, thrombosis resistance, etc. and also a process for producing the polyurethane are provided, which polysiloxane compound expressed by the formula ##STR1## wherein R represents H, Me (methyl) or Et (ethyl) and n represents an integer of 0 to 4,000, and which silicone-modified polyurethane is obtained from a compound having at least two isocyanate groups and a compound having at least two hydroxyl groups, and by using as a part of the compound having at least two hydroxyl groups, the polysiloxane compound of the above formula (I) in the urethane bond-forming reaction.
    Type: Grant
    Filed: January 14, 1988
    Date of Patent: June 13, 1989
    Assignee: Chisso Corporation
    Inventors: Yoshinori Akutsu, Takaharu Nakano, Takahiro Saho, Nobumasa Ohtake, Hirofumi Yasuda, Tamio Kimura
  • Patent number: 4822850
    Abstract: There is here provided a modifier for a resin containing an active hydrogen capable of reacting with an isocyanate group. The modifier of the present invention can give characteristics such as low frictional properties, water repellency, oil repellency and antithrombotic properties to the resin, and when the modifier of the present invention is used, neither bleeding phenomenon nor deterioration in mechanical strength takes place.The present modifier comprises a modified polyorganosiloxane containing an isocyanate group which is represented by the general formula (A) ##STR1## wherein Me is a methyl group, Ph is a phenyl group, R is a methyl or phenyl group, R.sup.1 is H or a methyl group, each of m and n is 0 or more and a value of m+n is within the range of 0 to 600, a is 1, 2 or 3, b is 1, 2 or 3, c is a value of 1 to 300, and Q is a residue obtained by subtracting one isocyanate group from a compound having at least two isocyanate groups.
    Type: Grant
    Filed: December 21, 1987
    Date of Patent: April 18, 1989
    Assignee: Chisso Corporation
    Inventors: Hirofumi Yashuda, Takahiro Saho, Nobumasa Ohtake, Takaharu Nakano
  • Patent number: 4658049
    Abstract: A novel carboxyl group-containing siloxane compound, whether its molecular weight is low or high, having a superior heat stability, and useful as emulsifying agent, surface modifier for inorganic materials, etc. is provided, which compound is expressed by the general formula ##STR1## wherein R represents an alkyl group of 1 to 4 carbon atoms; R.sup.1 represents R or R.sup.2 ; R.sup.2 represents CH.sub.2 CH.sub.2 CH.sub.2 --OCH.sub.2 CH.sub.2).sub.n COOH; n is an integer of 1 or more; l is an integer of 0 or more; m is an integer of 0 or more; l+m is an integer of 1 or more; and R.sup.1 represents R.sup.2 in the case of m=0.
    Type: Grant
    Filed: December 12, 1985
    Date of Patent: April 14, 1987
    Assignee: Chisso Corporation
    Inventors: Takaharu Nakano, Nobumasa Ohtake
  • Patent number: 4269993
    Abstract: Novel diaralkyldichlorosilanes expressed by the general formula (I) ##STR1## (wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each represent hydrogen atom or an alkyl group having 1.about.4 carbon atoms, but a case where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are all hydrogen atom is excluded),and a process for producing the same are provided.They are useful as monomers for producing polysiloxanes and as intermediates for synthesizing novel organosilicon compounds.
    Type: Grant
    Filed: October 15, 1979
    Date of Patent: May 26, 1981
    Assignee: Chisso Corporation
    Inventors: Nobumasa Ohtake, Isao Koga, Yohji Terui
  • Patent number: 4211704
    Abstract: A commercial method for producing 2,3,3-trimethylindolenine useful as an intermediate for cationic dyes, etc., with a high yield is provided, which comprises mixing aniline with 3-chloro-3-methylbutane-2-one in a mixing ratio by mol of 3:1-10:1; reacting the resulting mixture at a temperature of 50.degree.-150.degree. C. for 2-20 hours; thereafter elevating the temperature of the reaction liquid; and maintaining the liquid at a reflux temperature of aniline for 0.5-2 hours to complete the reaction.
    Type: Grant
    Filed: August 2, 1978
    Date of Patent: July 8, 1980
    Assignee: Chisso Corporation
    Inventors: Nobumasa Ohtake, Ryo Yoshizawa, Isao Koga