Patents by Inventor Sakuro Hasegawa

Sakuro Hasegawa 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).

  • Pulp slurry drainage improver
    Patent number: 4704190
    Abstract: Drainage of pulp slurry can be markedly improved without impairing the uniformity of paper quality by adding to the pulp slurry a poly-monoallylamine resin represented by the formula: ##STR1## wherein X is Cl, Br, I, HSO.sub.4, HSO.sub.3, H.sub.2 PO.sub.4, H.sub.2 PO.sub.3, HCOO, CH.sub.3 COO or C.sub.2 H.sub.5 COO, n is a number of 10 to 100,000, and m is 0 or 1, or a modified resin of the poly-monoallylamine resin.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: November 3, 1987
    Assignee: Nitto Boseki Co., Ltd.
    Inventors: Susumu Harada, Sakuro Hasegawa
  • Polymers of N-substituted secondary monoallylamines and their salts and process for producing the same
    Patent number: 4644042
    Abstract: N-substituted secondary monoallylamine salts can be easily polymerized in a polar solvent by using as catalyst a water-soluble radical initiator containing azo group in the molecule, and polymers with a high degree of polymerization can be obtained therefrom in a high yield.
    Type: Grant
    Filed: August 27, 1985
    Date of Patent: February 17, 1987
    Assignee: Nitto Boseki Co., Ltd.
    Inventors: Toshio Ueda, Kenji Kageno, Kiyoshi Shimizu, Sakuro Hasegawa, Susumu Harada
  • Small-globular crosslinked monoallylamine polymer and process for producing the same
    Patent number: 4605701
    Abstract: A small-globular crosslinked polymer of monoallylamine swellable but insoluble in water can be obtained by crosslinking a part of the amino groups of a monoallylamine polymer with formaldehyde or a compound having, in its molecule, at least two functional groups reactive with primary amino group.
    Type: Grant
    Filed: October 19, 1984
    Date of Patent: August 12, 1986
    Assignee: Nitto Boseki Co., Ltd.
    Inventors: Susumu Harada, Sakuro Hasegawa, Koichi Sato
  • Process for producing a polymer of an inorganic acid salt of monoallylamine
    Patent number: 4569979
    Abstract: The use of a radical initiator of azo compound type represented by the following general formula (I) enables polymerization of an inorganic acid salt of monoallylamine, whereby a polymer of an inorganic acid salt of monoallylamine having a high polymerization degree can be obtained in a high yield, ##STR1## [In the above formula, A and B independently are an alkylene group of 2 to 3 carbon atoms which may have one or more substituents on the carbon atom or atoms; R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 may be same or different and independently are a hydrogen atom or a hydrocarbon group; and X is a monovalent anion selected from the group consisting of Cl, Br, NO.sub.3, HSO.sub.4, H.sub.2 PO.sub.4, HSO.sub.3, HCOO, CH.sub.3 COO, ##STR2## and CH.sub.3 SO.sub.4.
    Type: Grant
    Filed: November 7, 1984
    Date of Patent: February 11, 1986
    Assignee: Nitto Boseki Co., Ltd.
    Inventors: Susumu Harada, Sakuro Hasegawa
  • Process for producing monoallylamine polymer
    Patent number: 4504640
    Abstract: By polymerizing an inorganic acid salt of monoallylamine in a polar solvent in the presence of a radical initiator having, in its molecule, an azo group and a group having cationic nitrogen atom, a polymer of monoallylamine having a high degree of polymerization can be obtained in high yield.
    Type: Grant
    Filed: May 19, 1982
    Date of Patent: March 12, 1985
    Assignee: Nitto Boseki Co., Ltd.
    Inventors: Susumu Harada, Sakuro Hasegawa