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:
Dec. 14, 1999
Filed:
Mar. 04, 1999
Yasuki Nagai, Kobe, JP;
Junji Machida, Toyonaka, JP;
Minolta Co., Ltd., Osaka, JP;
Abstract
The present invention relates to a process for preparing a toner for electrophotography, which comprises at least the steps of: providing a toner composition solution by mixing a binder resin, a colorant, a charge-control agent and an organic solvent; mixing the resulting toner composition solution with a dispersion solution containing a dispersing agent by utilizing a collision shearing force of beads or using a colloid mill method, thereby obtaining an O/W type emulsion; heating the resulting emulsion so as to eliminate said organic solvent; and obtaining a toner by washing and drying precipitated particles, wherein a viscosity .eta..sub.Z of the toner composition solution and a viscosity .eta..sub.B of the dispersion solution satisfies a specified the relationship between .eta..sub.A and .eta..sub.B.