Ricoh Company, Ltd.

Koh Ohnuma

Tsuyoshi Sugimoto

Kohsuke Nagata

Shin Hasegawa

Hideyuki Santo

Suzuka Karato

Shinya Nakayama

Akinori Saitoh

Hiroshi Yamada

Suzuka Amemori

Shinsuke Nagai

Takahiro Kadota

Ryuuta Yoshida

Akihiro Takeyama

Hideyuki Santoh

Provided is a toner including a crystalline polyester resin including a constitutional unit derived from saturated aliphatic dicarboxylic acid and a constitutional unit derived from saturated aliphatic diol, an amorphous hybrid resin, an amorphous polyester resin, a release agent, and a colorant, wherein the crystalline polyester resin includes a constitutional unit derived from sebacic acid as the constitutional unit derived from the saturated aliphatic dicarboxylic acid, and the amorphous hybrid resin is a composite resin including a polyester-based resin unit and a styrene-based resin unit.

Toner, developer, and image forming apparatus

A toner is provided. The toner includes an amorphous resin, a crystalline resin dispersed in the amorphous resin, and a release agent. The toner satisfies the following inequality:&#x3c;0.8where A represents a perimeter of the crystalline resin and B represents a length of a part of the perimeter A of the crystalline resin at which the crystalline resin is in contact with the amorphous resin, A and B being measured from a cross-sectional image of the toner observed with transmission electron microscope.

Toner, toner storage unit, image forming apparatus, and method for manufacturing toner

Toner that includes a polyester resin, fluorine and aluminum. The toner satisfies formulae (1) and (2),1.00&#x2267;&#x2267;0.50&#x2003;&#x2003;(1)0&#x2266;()/&#x2266;0.25&#x2003;&#x2003;(2)

Toner, toner stored unit, image forming apparatus, and image forming method

A toner includes a base particle including a polyester resin and a colorant. A sea-island structure is observed by a transmission electron microscope (TEM) in a cross-sectional image of the toner. The island structure includes the colorant and has an average diameter of from 0.2 &#x3bc;m to 1.0 &#x3bc;m, and the number of the island structure is from 5 to 30.

Toner, developer and developer containing unit

A toner includes a polyester resin including a polyester resin component A (A) insoluble in tetrahydrofuran; and a polyester resin component B (B) soluble in tetrahydrofuran. The toner has a first glass transition temperature (Tg1st) of from 20&#xb0; C. to 50&#xb0; C., measured at a first temperature rising in differential scanning calorimetry (DSC), and satisfies the following formulae (1) and (2):=1/{/(+273)+/(+273)}&#x2212;273&#x2003;&#x2003;(1)&#x3e;30&#xd7;&#x2003;&#x2003;(2)wherein a and b represent weight ratios of (A) and (B) to a total weight of (A) and (B), and satisfy the equation a+b=1; and TgA, TgB and TgAB represent second glass transition temperatures (Tg2nd), measured at a second temperature rising in differential scanning calorimetry, of (A), (B), and a mixture of (A) and (B), respectively.

Toner, developer, image forming apparatus, and process cartridge

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Shizuoka, Japan

Koh Ohnuma