Patents by Inventor Syogo Iwai

Syogo Iwai 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).

  • Method for producing polycarboxylic acid for cement dispersant and cement composition
    Patent number: 6388038
    Abstract: The present invention provides a method for producing a cement dispersant having high percentage in water reduction rate and appropriate air-entraining property. This method for producing a polycarboxylic acid for a cement dispersant is characterized in that alkylene oxide is added at a specific temperature range.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: May 14, 2002
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Tsuyoshi Hirata, Tsutomu Yuasa, Katsuhisa Shiote, Koichiro Nagare, Syogo Iwai
  • Cement dispersant, method for producing polycarboxylic acid for cement dispersant and cement composition
    Patent number: 6174980
    Abstract: The present invention provides a method for producing a cement dispersant having high percentage in water reduction-rate and appropriate air-entraining property. This method for producing a polycarboxylic acid for a cement dispersant is characterized in that alkylene oxide is added at a specific temperature range.
    Type: Grant
    Filed: December 16, 1997
    Date of Patent: January 16, 2001
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Tsuyoshi Hirata, Tsutomu Yuasa, Katsuhisa Shiote, Koichiro Nagare, Syogo Iwai
  • Cement additive, its production process and use
    Patent number: 5912284
    Abstract: The present invention provides a cement additive its production process and cement composition achieving excellent slump loss prevention capability. As a cement additive, there can be a copolymer (A-1) comprising an unsaturated polyalkylene glycol ether-based monomer (I), maleic acid-based monomer (II) and other monomer (III) copolymerizable with these monomers, the monomer (I)/monomer (II)/monomer (III) weight ratio being 50-99/50-1/0-49 and the weight average molecular weight of the copolymer (A) being 10,000 to 100,000 in terms of polyethylene glycol measured by gel permeation chromatography, or a copolymer (A) with an antifoaming agent (B), wherein the copolymer (A) comprises polyalkylene glycol ether-based units and dicarboxylic acid-based units as repeating units.
    Type: Grant
    Filed: December 17, 1997
    Date of Patent: June 15, 1999
    Assignee: Nippon Shokubai Co., Ltd.
    Inventors: Tsuyoshi Hirata, Tsutomu Yuasa, Katsuhisa Shiote, Syogo Iwai, Koichiro Nagare
  • Automatic document feeder for electrophotographic copying machine with a drum for supporting a document
    Patent number: 4910552
    Abstract: An electrophotographic copying machine of a type having a drum for supporting a document to be copied therearound and being provided with an automatic document feeder adapted to carry out a preliminary copying operation for testing includes a timer for counting up a predetermined period of time after the completion of preliminary copying, or is alternatively so programmed that a choice can be made after a preliminary copying operation whether a document remaining in the copying position should be ejected. Jamming of documents and injury to the copying machine can be avoided effectively thereby.
    Type: Grant
    Filed: January 19, 1989
    Date of Patent: March 20, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Haruyoshi Migita, Hirokazu Matsuura, Syogo Iwai