The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 15, 1997
Filed:
Jan. 28, 1993
Applicant:
Inventors:
Koji Yoshioka, Fujioka, JP;
Yasuaki Ogiwara, Tomioka, JP;
Mitsuhiko Furusawa, Gumma-ken, JP;
Kyoko Kobayashi, Fujioka, JP;
Assignee:
Mitsubishi Pencil Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C03C / ;
U.S. Cl.
CPC ...
523160 ; 523161 ; 524575 ; 106 / ; 106 / ;
Abstract
The present invention provides an erasable writing ink composition which can be erased with an eraser after writing. The erasable writing ink composition of the present invention comprises 2 to 50% by weight of a resin selected from the group consisting of styrene-butadiene rubber and an acrylonitrile-butadiene rubber having a film-forming temperature of 0.degree. C. or less or a glass transition temperature of 0.degree. C. or less, 0 to 5% by weight of a surface active agent, 1 to 50% by weight of colored spherical fine particles and 20 to 97% by weight of water.