Canon Kabushiki Kaisha

Canon Kabusbiki Kaisha

Kengo Hayase

Tatsuya Nakamura

Tatsuhiko Chiba

Kohji Inaba

Masayoshi Kato

Kazunori Kato

Shuichi Aita

Koji Inaba

Takao Ishiyama

Yuki Nishio

An apparatus unit includes a detachably mounted unit having a developing sleeve, a toner and a toner applicator, all of which are enclosed by an outer casing. The toner has a shape factor SF-1 of 100-150 and is formed of 100 parts binder, 1-20 parts of a non-magnetic color and 5-40 parts wax and has a specific storage modulus ratio (a) at 60.degree. C. and 80.degree. C. and (b) at 155.degree. C. and 190.degree. C., of at least 80 for (a) and of 0.95-5 for (b). Toner images are visualized by forming an electrostatic image, developing the electrostatic image with the toner, transferring the toner image to a transfer material and fixing the toner image by heat and pressure.

Toner for developing electrostatic image, apparatus unit and image

Image forming method

A toner for developing an electrostatic image includes: 100 wt. parts of a binder resin, 1-150 wt. parts of a colorant and a relatively large amount of 5-40 wt. parts of a low-softening point substance. The toner is further characterized by viscoelastic properties including: a storage modulus at 60.degree. C. (G'.sub.60) and a storage modulus at 80.degree. C. (G'.sub.80) providing a ratio (G'.sub.60 /G'.sub.80) of at least 80, and a storage modulus at 155.degree. C. (G'.sub.155) and a storage modulus at 190.degree. C. (G'.sub.190) providing a ratio (G'.sub.155 /G'.sub.190) of 0.95-5. As a result, the toner shows good low-temperature fixability and anti-offset characteristic, and also little temperature-dependence of gloss.

Toner for developing electrostatic image containing crosslined styrene

A toner for developing an electrostatic image includes toner particles constituted by at least a binder resin, a colorant, a polar resin and a release agent. The polar resin has at least one terminal group which has been modified by a polycarbonate acid having at least three carboxyl groups. The polar resin has an acid value of 3-35 mgKOH/g. The polar resin may preferably be a polyester resin having an acid value of 4-35 mgKOH/g and having a number-average molecular weight (Mn) of 3,000-15,000, a weight-average molecular weight (Mw) of 6,000-50,000, and an Mw/Mn of 1.2-3.0 based on GPC. The polar resin (preferably polyester resin) having modified by a polycarboxylic acid having at least three carboxylic groups to provide a specific acid value is effective in improving resultant toner performances, such as low-temperature fixability, anti-offset characteristic at high temperatures, triboelectric chargeability, and flowability.

Toner for developing electrostatic image

The present invention relates to a toner for developing an electrostatic image, comprising toner particles containing a binding resin composed of a styrene homopolymer or copolymer, a coloring agent, a polar resin, and a specified solid ester wax.

A toner for developing electrostatic images includes: at least a binder resin, a colorant and an ester wax. The ester wax is contained in 3-40 wt. parts per 100 wt. parts of the binder resin. The ester wax includes ester compounds represented by a formula of

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Tokyo, Japan

Kengo Hayase