Patents by Inventor Kenzo Seita

Kenzo Seita 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).

  • Polymer and applications thereof
    Patent number: 6255400
    Abstract: A polymer (B) is prepared by polymerizing one or more vinyl monomers (c) in the presence of a polymer (A) prepared by polymerizing one or more vinyl monomers (a) selected from the group consisting of vinyl monomers represented by the general formula (1): wherein R1 represents a hydrogen atom or a lower alkyl with 1 to 3 carbon atoms and n is an integer of 1 to 8 and their salts with one or more vinyl monomers (b) which are co-polymerizable with the vinyl monomer components (a).
    Type: Grant
    Filed: November 23, 1998
    Date of Patent: July 3, 2001
    Assignee: Mitsui Chemicals, Inc.
    Inventors: Hiroshi Itoh, Susumu Oyama, Takashi Yodoya, Kenji Tsuboi, Tsugio Matsubara, Kenichi Nakamura, Hirotoshi Doki, Shinya Yamagami, Toshiki Oyanagi, Kenzo Seita
  • Lightweight paper and process for producing same
    Patent number: 4783240
    Abstract: A lightweight paper having a superior opacity and printing opacity is provided, which lightweight paper comprises dry pulp, 0.015 to 1.2% by weight based on the pulp of an alumina polymer and 0.5 to 30% by weight based on the pulp of a coaggregate formed from agglomerated particles of urea-formal-dehyde polymer (A) and agglomerated particles of hydrated silicic acid (B) in a ratio of (A):(B) of 5:95 to 95:5.
    Type: Grant
    Filed: October 16, 1986
    Date of Patent: November 8, 1988
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Akio Kurokawa, Naoyuki Ifuku, Kenzo Seita, Youzi Nagata
  • Process for producing crosslinked urea-formaldehyde polymer particles
    Patent number: 4433133
    Abstract: Disclosed is a process for producing fine particles of crosslinked urea-formaldehyde polymer which comprises the steps of synthesizing a precondensate of urea and formaldehyde, allowing the precondensate to react by the addition of an aqueous solution of an acid catalyst, and then neutralizing the reaction mixture, characterized in that the filtrate obtained in the filtration step for separating the polymer particles is recycled to the reaction system at the step of synthesizing a precondensate of urea and formaldehyde and/or the step of allowing the precondensate to react by the addition of an aqueous solution of an acid catalyst and in that the precondensate is obtained by reaction 1 mole of urea with 1.4 to 1.9 moles of formaldehyde at a pH of 6 to 10 and a temperature of 10 to 95.degree. C.
    Type: Grant
    Filed: March 28, 1983
    Date of Patent: February 21, 1984
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Naoyuki Ifuku, Akio Kurokawa, Kenzo Seita, Kaoru Usami, Naoyuki Aikawa