Canon Kabushiki Kaisha

Yusuke Karami

Takashige Kasuya

Satoshi Matsunaga

Hiroaki Kawakami

Shinji Doi

Yasuhide Goseki

Masuo Yamazaki

Kiyoko Tsuchiya

Kiyoko Maeda

Satoshi Yoshida

Yasutaka Akashi

Satoshi Yasuda

Hitoshi Kanda

Seiichi Takagi

Mitsuru Uchida

Atsuko Kobayashi

A heat fixable toner comprises a binder resin and a release agent. The binder resin comprises a polyester resin, and the release agent comprises a graft-modified polyolefin. A recording medium containing a toner image of said heat fixable toner is heat-fixed by contacting the recording medium with a heater element through a film interposed therebetween. After the heat-fixing step, the film is peeled from the fixed toner image while the film surface temperature is higher than the endothermic peak temperature of the toner.

Heat fixing method employing peelable film between heater and recording

A heat fixable toner comprises a binder resin and a release agent. The binder resin comprises a polyester resin, and the release agent comprises a graft-modified polyolefin.

Fixable toner with a modified bisphenolic polyester resin

A toner for developing an electrostatic image, comprises a binder resin and a colorant. Such binder resin contains a THF-insoluble component in an amount of less than 10 wt. % based on the binder resin, and, in the molecular weight distribution measured by GPC (gel permeation chromatography) of a THF-soluble component, has a weight average molecular weight/number average molecular weight (Mw/Mn) of .gtoreq.18, a molecular weight peak MA in the region of a molecular weight of from 3,000 to 20,000, a molecular weight peak MB in the region of a molecular weight of from 380,000 to 1,000,000, a molecular weight minimum Md in the region of a molecular weight of from 20,000 to 380,000, provided that MB/MA is in the range of from 30 to 150, and a molecular weight distribution curve area ratio SA:SB:Sd of 1:0.3 to 0.8:0.35 to 0.8.

Electrostatic image developing toner and fixing method

A microcapsule toner is produced through the steps of: passing resinous base particles (A1) comprising at least a binder resin and modifier particles (B) having a particle size ratio of 0.2 or less with respect to the base particles (A1) through an impact zone having a minimum clearance of 0.5-5 mm between a rotating member and a fixed member or between at least two rotating members at an ambient temperature of 10.degree.-90.degree. C. thereby to fix the modifier particles (B) onto the surfaces of the base particles (A1) under the action of a mechanical impact force to form particles (A2), the modifier particles (B) being particles selected from the group consisting of charge-controlling particles releasing particles, colored particles, charge-suppressing particles and abrasive particles; and passing the particles (A2) and shell-forming resin particles (C) having a particle size ratio of 0.2 or less with respect to the particles (A2) through an impact zone having a minimum clearance of 0.5-5 mm between a rotating member and a fixed member or between at least two rotating members at an ambient temperature of 10.degree.-90.degree. C. thereby to fix the shell-forming resin particles onto the surfaces of the particles (A2) under the action of a mechanical impact force to form a shell, thus obtaining a microcapsule toner.

Process for producing microcapsule toner

A toner for developing an electrostatic image, comprises a binder resin and a colorant. Such binder resin contains a THF-insoluble matter in an amount of less than 10 wt. % based on the binder resin, and, in the molecular weight distribution measured by GPC (gel permeation chromatography) of a THF-soluble matter, has a weight average molecular weight/number average molecular weight (Mw/Mn) of .gtoreq.18, a molecular weight peak MA in the region of a molecular weight of from 3,000 to 20,000, a molecular weight peak MB in the region of a molecular weight of from 380,000 to 1,000,000, a molecular weight minimum Md in the region of a molecular weight of from 20,000 to 380,000, provided that MB/MA is in the range of from 30 to 150, and a molecular weight distribution curve area ratio SA:SB:Sd of 1:0.3 to 0.8:0.35 to 0.8.

A method of heat-fixing a visible image of toner to a recording medium comprises applying a toner image onto the recording medium, wherein

Method of heat-fixing toner image

A magnetic dry developer, comprising negatively chargeable insulating magnetic toner particles containing, at least, a binder resin, a magnetic substance, and an organo-chromium or -zinc complex; cerium oxide particles containing CeO.sub.2 as a predominant component and having a volume average particle size of 1.0 to 4.0 microns, a heating loss of 0.5 wt. % or less on heating up to 100.degree. C. and a BET specific surface area of 15 m.sup.2 /g or less as measured by the nitrogen adsorption method; and hydrophobicity-imparted negatively chargeable silicon oxide particulates. The cerium oxide particles have a function of disintegrating particularly the hydrophobicity-imparted silicon oxide particulates and enhance the attachment thereof to the toner particles, whereby the developing characteristics including the magnetic triboelectric chargeability are stabilized from the initial stage of electrophotographic copying operation.

Growing community of inventors

Yokohama, Japan

Yusuke Karami