Patents by Inventor Toshifumi Watanabe

Toshifumi Watanabe 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: 6140325
    Abstract: Thienopyrimidine derivatives are disclosed. Also disclosed are methods for the production and use of these compounds.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: October 31, 2000
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Shuichi Furuya, Nobuo Choh, Tetsuya Ohtaki, Toshifumi Watanabe
  • Patent number: 6021288
    Abstract: A digital copying machine develops an electrostatic latent image formed on a photosensitive drum with toner, and transfers the developed image onto a sheet. In forming images on the photosensitive drum successively, three types of test patterns are formed in order in intro-image areas between image forming areas, and AIDC is made. The first test pattern is a low-density pattern, the second test pattern is an intermediate-density pattern, and the third test pattern is a high-density pattern.
    Type: Grant
    Filed: September 21, 1998
    Date of Patent: February 1, 2000
    Assignee: Minolta Co., Ltd.
    Inventors: Yukihiko Okuno, Masaki Tanaka, Toshifumi Watanabe
  • Patent number: 5978615
    Abstract: Using an image forming apparatus, toner images are respectively formed on photosensitive drums of image forming units set along a transport belt, and the toner images are transferred onto the transport belt or a recording sheet transported on the transport belt to form a color image.
    Type: Grant
    Filed: September 28, 1998
    Date of Patent: November 2, 1999
    Assignee: Minolta Co., Ltd.
    Inventors: Masaki Tanaka, Yukihiko Okuno, Toshifumi Watanabe
  • Patent number: 5925731
    Abstract: The peptide derivatives having endothelin receptor-antagonistic action or a salt thereof and medicinal compositions containing them are provided.Since peptide derivatives or a salt thereof of this invention exhibit remarkable endothelin receptor-antagonistic action with low toxicity, they are effective as medicines for prophylaxis and therapy of, for example, cardio- or cerebro-circulatory diseases hepatic diseases and/or renal diseases.
    Type: Grant
    Filed: October 28, 1996
    Date of Patent: July 20, 1999
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Chieko Kitada, Taiji Asami, Tetsuya Ohtaki, Toshifumi Watanabe
  • Patent number: 5891895
    Abstract: Hydroxypyridine derivatives of the formula ##STR1## wherein R.sup.1 is a branched C.sub.3-8 alkyl group or a C.sub.3-8 cycloalkyl group, each of which may be substituted;R.sup.2 is a halogen atom, a C.sub.1-4 alkyl group or a C.sub.1-4 alkoxy group;X is an oxygen atom or NR.sup.3 in which R.sup.3 is a hydrogen atom or a C.sub.1-4 alkyl group;R.sup.4, R.sup.5 and R.sup.6 are independently (1) a hydrogen atom, (2) a halogen atom, (3) a cyano group, (4) a nitro group, (5) a C.sub.1-4 acyl group, (6) a C.sub.1-4 alkoxy group which may be substituted with halogen, (7) a C.sub.1-4 alkyl group which may be substituted with halogen or (8) a mercapto group which may be substituted with a C.sub.1-4 alkyl group;m is 0 to 3; andn is 0 or 1;provided that all of R.sup.4, R.sup.5 and R.sup.6 are not hydrogen atom, or a salt thereof, which have potassium channel opening activity and are useful as therapeutic agents of cardiovascular diseases such as angina pectoris, hypertension, etc.
    Type: Grant
    Filed: April 14, 1997
    Date of Patent: April 6, 1999
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Mitsuru Shiraishi, Tsuyoshi Maekawa, Toshifumi Watanabe
  • Patent number: 5860041
    Abstract: A device for measuring toner concentration of developer housed in a developing system, which developer comprising toner and carrier. The device has a transparent detection window facing the interior of the developing system, which transparent detection window comprising a first transparent plate member and a second transparent plate member being in contact with the first transparent plate member. The first transparent plate member is made of a material which becomes charged, through its contact with the second transparent plate member, with the opposite polarity from the charge polarity of the toner and the second transparent plate member is made of a material which becomes charged, through its contact with the carrier, with the same polarity from the charge polarity of the toner, so that the second transparent plate member strongly repels the toner having the same polarity charge and adherence of the toner to the second transparent plate member is reliably prevented.
    Type: Grant
    Filed: November 5, 1997
    Date of Patent: January 12, 1999
    Assignee: Minolta Co., Ltd.
    Inventors: Masaki Tanaka, Kuniya Matsuura, Toshifumi Watanabe
  • Patent number: 5822079
    Abstract: An image forming apparatus is provided which is immune to characteristic variations of a photoconductor and a developer material, which can detect the amount of toner adhering to a test toner image accurately, and which can always form a favorable image using an optimal image forming parameter. A predetermined test toner image is formed on the photoconductor using developing devices. The amount of toner adhering to the formed test toner image is detected by an AIDC sensor. A printer control unit determines grid potential Vg of a corona charger and development bias potential Vb of each developing device based on the detected amount of adhering toner. A predetermined image is formed using the determined grid potential and development bias potential.
    Type: Grant
    Filed: March 6, 1996
    Date of Patent: October 13, 1998
    Assignee: Minolta Co., Ltd.
    Inventors: Yukihiko Okuno, Toshifumi Watanabe, Kentaro Katori
  • Patent number: 5753619
    Abstract: Cyclic hexapeptides having antagonistic activity on endothelin receptors of the formula ?I!: ##STR1## wherein X and Y each is an .alpha.-amino acid residue having D-, L-form or DL-form, A is a D-acidic-.alpha.-amino acid residue, B is a neutral-.alpha.-amino acid residue having D- or L-form, C is an L-.alpha.-amino acid residue and E is a D-.alpha.-amino acid residue having an aromatic ring group can be effectively used for prophylaxis and/or treatment of pulmonary circulatory diseases.
    Type: Grant
    Filed: November 29, 1995
    Date of Patent: May 19, 1998
    Assignee: Takeda Chemical Insustries, Ltd.
    Inventors: Toshifumi Watanabe, Keiji Kusumoto, Mitsuhiro Wakimasu
  • Patent number: 5716971
    Abstract: Pyridine derivatives of the formula ##STR1## wherein the ring A stands for an optionally further substituted benzene ring; the ring B stands for an optionally substituted pyridine ring; Q stands for hydroxyl group, or OQ.sup.1 or Q.sup.1 wherein Q.sup.1 stands for an optionally substituted aliphatic hydrocarbon group; and n denotes 0 or 1, or their salts, which have potassium.channel opening activity and are useful as therapeutic agents of circulatory diseases such as angina pectoris, hypertension, etc.
    Type: Grant
    Filed: August 9, 1996
    Date of Patent: February 10, 1998
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Mitsuru Shiraishi, Toshifumi Watanabe
  • Patent number: 5708918
    Abstract: An image formation apparatus for forming a full color image in the four colors of cyan, magenta, yellow and black has a optical ATDC sensor attached in a cyan developing device to control the toner density under optical ATDC. A black developing device has the toner density controlled by AIDC. A standard develop efficiency .eta.STD of the cyan developing device obtained as a result of the AIDC is compared with a develop efficiency .eta. of black toner. The toner supply amount of the black developing device is determined according to the comparison result to supply the toner. Thus, an image formation apparatus is provided that can detect at favorable accuracy the toner density of a developing device incorporating a developer of which the toner density cannot be detected using optical ATDC to supply a required amount of toner.
    Type: Grant
    Filed: October 8, 1996
    Date of Patent: January 13, 1998
    Assignee: Minolta Co., Ltd.
    Inventors: Yukihiko Okuno, Masaki Tanaka, Naoyoshi Kinoshita, Atsushi Kawai, Toshifumi Watanabe
  • Patent number: 5694223
    Abstract: A printer control unit carries out a predetermined calculation based on the amount of adhering toner detected by an AIDC sensor and the surface potential of a photoconductor detected by a V sensor to correct the light emission intensity of a light source to prepare light emission characteristic data for .gamma. correction to obtain an optimal image. A .gamma. correcting unit corrects an image signal output from an image signal processing unit using the calculated light emission characteristic data for .gamma. correction to control the light source to emit light based on the corrected data. More specifically, since the .gamma. correction data is obtained by calculation, optimal .gamma. correction can always be carried out without a memory of a large capacity.
    Type: Grant
    Filed: March 6, 1996
    Date of Patent: December 2, 1997
    Assignee: Minolta Co., Ltd.
    Inventors: Kentaro Katori, Toshifumi Watanabe, Yukihiko Okuno, Masaki Tanaka, Hironobu Nakata, Katsuyuki Hirata
  • Patent number: 5581221
    Abstract: A copying machine wherein a developing device is provided with a first sensor for detecting the toner density in a developer and a second sensor which is provided around a photosensitive drum for detecting the amount of deposited toner on a test pattern. The toner supply is controlled according to a result detected by the second sensor. When the toner density is judged high from a result detected by the first sensor, a developing bias voltage is set high by a computer, and when the toner density is judged low, the developing bias voltage is set low.
    Type: Grant
    Filed: December 13, 1994
    Date of Patent: December 3, 1996
    Assignee: Minolta Co. Ltd.
    Inventors: Atsushi Kawai, Hiroshi Sakakibara, Toshifumi Watanabe, Tetsuya Sakai, Hiroshi Nishikawa
  • Patent number: 5555318
    Abstract: In a thresholding method for segmenting gray scale image which is less dependent on the concentration distribution of the input image, the threshold in determined as a zero-cross point of a histogram difference between the concentration histograms for the gray scale image within the window at a window position at which the window contains more high concentration region and at a window position at which the window contains more low concentration region. Also, in a method of determining a background concentration distribution from an image having an arbitrarily distributed pattern, the background concentration level is determined as a peak concentration or a mean value concentration of a low concentration section of the histogram difference of the concentration histograms for two associated windows.
    Type: Grant
    Filed: November 7, 1995
    Date of Patent: September 10, 1996
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Minoru Ito, Toshifumi Watanabe
  • Patent number: 5506917
    Abstract: In a thresholding method for segmenting gray scale image which is less dependent on the concentration distribution of the input image, the threshold in determined as a zero-cross point of a histogram difference between the concentration histograms for the gray scale image within the window at a window position at which the window contains more high concentration region and at a window position at which the window contains more low concentration region. Also, in a method of determining a background concentration distribution from an image having an arbitrarily distributed pattern, the background concentration level is determined as a peak concentration or a mean value concentration of a low concentration section of the histogram difference of the concentration histograms for two associated windows. Also.
    Type: Grant
    Filed: July 11, 1991
    Date of Patent: April 9, 1996
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Minoru Ito, Toshifumi Watanabe
  • Patent number: 5364684
    Abstract: Disclosed herein is a magnetic recording medium comprising:a stretched polyethylene-2,6-naphthalate multilayered film having a high-roughness surface and a low-roughness surface;a coating layer (A) having specific surface properties and being formed on the high-roughness surface of said multilayered film;a coating layer (B) having a specific surface property and being formed on the low-roughness surface of said multilayered film; anda thin ferromagnetic metal film formed on said coating layer (B).
    Type: Grant
    Filed: July 6, 1992
    Date of Patent: November 15, 1994
    Assignee: Diafoil Hoechst Company, Limited
    Inventors: Seiji Sakamoto, Toshifumi Watanabe, Toshifumi Takisawa
  • Patent number: 5270308
    Abstract: A new compound of the formula: ##STR1## wherein ##STR2## is an optionally substituted benzene ring; R.sup.1 is a carbocyclic or heterocyclic group which is linked to the 4-position of the 1,3-benzoxazine ring through a carbon-carbon bond, a hydrocarbon residue, etc.; and R.sup.2 and R.sup.3 are independently a hydrogen atom or an optionally substituted C.sub.1-6 alkyl group, etc., or a salt thereof is useful for treating and preventing heart, circulatory, respiratory and cerebral diseases.
    Type: Grant
    Filed: September 25, 1991
    Date of Patent: December 14, 1993
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Mitsuru Shiraishi, Shohei Hashiguchi, Toshifumi Watanabe