Fuji Xerox Co., Ltd.

Fujifilm Business Innovation Corp.

Koji Funaba

Masahiro Uchida

Katsuyuki Kitajima

Takafumi Koide

Masataka Kuribayashi

Yusuke Fukuda

Satomi Hara

Kana Yoshida

Teppei Yawada

Yuka Ishihara

Tatsuhiro Igarashi

Makoto Kamisaki

Manabu Furuki

Jun Sekiya

A toner for electrostatic charge image development has toner particles containing a binder resin including 90 mass % or more of an amorphous resin. In a differential molecular weight distribution curve of tetrahydrofuran soluble matter as measured by gel permeation chromatography, the toner has a maximum peak Ma in a molecular weight range of 2,500 or more and 8,000 or less, a minimum value Mm in a molecular weight range of more than 8,000 and less than 280,000, and a maximum peak Mb in a molecular weight range of 280,000 or more and 900,000 or less. When the area of the differential molecular weight distribution curve in a range of a molecular weight of 100 or more and less than the minimum value Mm is defined as A, and the area of the differential molecular weight distribution curve in a range of the minimum value Mm or more and a molecular weight of 10,000,000 or less is defined as B, the area ratio A/B is 5.5 or more and 10 or less.

Toner for electrostatic charge image development, electrostatic charge image developer, and image forming apparatus

An image forming apparatus includes an image holding member, a charging unit; an electrostatic image forming unit, a development unit, a transfer unit; a fixing unit, and a cleaning unit. A toner for electrostatic image development contains a binder resin containing an amorphous resin and a crystalline resin, and paraffin wax. The toner has a volume-average particle diameter of 6 &#x3bc;m to 9 &#x3bc;m, a shape factor SF1 of 140 or more, and a toluene insoluble content within a range of 25% to 40%. The melting temperature of the paraffin wax is 60&#xb0; C. or more and 80&#xb0; C. or less. The absolute value of difference between the melting temperature of the crystalline resin and the melting temperature of the paraffin is 10&#xb0; C. or less.

Image forming apparatus

An image forming apparatus includes a transfer unit which includes a belt member having an outer peripheral surface which contacts an image holding member, and a transfer member, and the belt member is wound around both of the image holding member and the transfer member, wherein a toner to be used includes a binder resin containing an amorphous resin and a crystalline resin and has specific physical properties described in the specification, and paraffin wax having a melting temperature of 60&#xb0; C. to 80&#xb0; C., and an absolute value of a difference between the melting temperature of the crystalline resin and the melting temperature of the paraffin wax is 10&#xb0; C. or less.

An image forming apparatus includes an image holding member, a charging unit, an electrostatic charge image forming unit, a developing unit, a transfer unit, a fixing unit including a fixing belt, a pressurizing rotator that forms a nip by pressurizing an outer peripheral surface of the fixing belt, a sliding member that slides on an inner peripheral surface of the fixing belt in the nip, and a pressing member that presses the fixing belt in the direction of the pressurizing rotator, wherein a toner to be used includes a binder resin containing an amorphous resin and a crystalline resin and has specific physical properties described in the specification, and paraffin wax having a melting temperature of 60&#xb0; C. to 80&#xb0; C., and an absolute value of a difference between the melting temperature of the crystalline resin and the melting temperature of the paraffin wax is 10&#xb0; C. or less.

An image forming apparatus includes a fixing unit including a fixing belt, a pressurizing rotator that forms a nip portion between the fixing belt and the pressurizing rotator by pressurizing an outer peripheral surface of the fixing belt, a first heating rotator that is provided so as to contact an inner peripheral surface of the fixing belt in the nip portion and heats the fixing belt, and a second heating unit that heats the fixing belt separately from the first heating rotator, wherein a toner to be used has physical properties described in the specification and includes an amorphous resin, a crystalline resin, and paraffin wax having a melting temperature of 60&#xb0; C. to 80&#xb0; C., and an absolute value of a difference in a melting temperature between the crystalline resin and the paraffin wax is 10&#xb0; C. or less.

A developing device includes a container that contains a developer containing a toner therein, a supply tank that is provided adjacent to the container and is supplied with the toner at a supply point within the supply tank, a transport member that is rotatably driven within the supply tank to transport the toner to the container, and an annular member, wherein the annular member has an inner diameter larger than a diameter of a rotatably-driven shaft in the transport member, the rotatably-driven shaft extends through the annular member, and the annular member is held in a partial section in a longitudinal direction of the rotatably-driven shaft.

Growing community of inventors

Kanagawa, Japan

Koji Funaba