Patents by Inventor Tada Tatsuya

Tada Tatsuya 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: 5340677
    Abstract: A carrier for electrophotography comprises a carrier core material and a coating resin material with which the surface of the carrier core material is coated. The carrier core material has a binder resin and fine magnetic material particles dispersed in the binder resin. The coating resin material contains at least one of the following members:(a) a vinyl copolymer having a hydroxyl value of from 1 to 100 (KOHmg/g);(b) a styrene-acrylic copolymer having an acrylic component in a monomer percentage of from 30% by weight to 90% by weight, a weight average molecular weight (Mw) of from 30,000 to 70,000 and a weight average molecular weight/number average molecular weight (Mw/Mn) of from 2 to 10; and(c) an insulating resin and a quaternary ammonium salt represented by the following Formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 may be the same of different and each represent an alkyl group, an aryl group or an aralkyl group; and A represents an organic anion or a polyacid ion.
    Type: Grant
    Filed: April 24, 1992
    Date of Patent: August 23, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshinobu Baba, Takeshi Ikeda, Tada Tatsuya, Yuko Sato, Yasuko Amano