Canon Kabushiki Kaisha

Ayako Okamoto

Takashige Kasuya

Kenji Aoki

Atsushi Tani

Takaaki Kaya

Shuntaro Watanabe

Tetsuya Kinumatsu

Toshifumi Mori

Yoshihiro Nakagawa

Provided is a toner containing toner particles, each of which includes a binder resin containing a polyester as a main component, a colorant, and a wax, in which the binder resin includes a block polymer in which a segment capable of forming a crystalline structure and a segment incapable of forming a crystalline structure are bonded, the toner has a maximum endothermic peak from the binder resin, as determined by differential scanning calorimetry measurement, with a peak temperature in a specific range and with an endothermic quantity in a specific range, and the wax is an ester wax having a functionality of 3 or more.

Toner

The present invention provides a toner excellent in low-temperature fixability and also excellent in heat-resistant storage property, offset resistance, and durability. In a process for producing a toner containing toner particles by emulsion aggregation, each toner particle includes a binder resin of which a main component is a block polymer having a crystal structure, a colorant, and a release agent; the binder resin includes polyester as a main component; the rate of a portion capable of forming a crystal structure to the binder resin is 50 to 80 mass %; a peak temperature Tp of a maximum endothermic peak attributed to the binder resin is 50 to 80&#xb0; C. in endothermic amount measurement of the toner with a differential scanning calorimeter (DSC); and fused particles are heated at a heating temperature t (&#xb0; C.) satisfying Tp'&#x2212;15.0&#x2266;t&#x2266;Tp&#x2032;&#x2212;5.0 for at least 0.5 hr.

Method of producing toner

In a toner formed of toner particles which include a colorant, a wax, and a binder resin containing a crystalline resin (a) primarily composed of a polyester, the crystalline resin has an endothermic peak temperature (Tp) in a range of 50&#xb0; C. to 80&#xb0; C., and in a viscoelasticity measurement of the toner, G&#x2033;(Tp&#x2212;10) is in a range of 5.0&#xd7;10to 5.0&#xd7;10Pa, G&#x2033;(Tp+10) is in a range of 5.0&#xd7;10to 5.0&#xd7;10Pa, and G&#x2033;(Tp&#x2212;20), G&#x2033;(Tp&#x2212;10), G&#x2033;(Tp+10), and G&#x2033;(Tp+30) satisfy specific relationships.

Provided is a toner comprising toner particles, wherein each of the toner particles has a core-shell structure composed of a core and a shell phase formed on the core, the shell phase contains a resin (B), and the core contains a binder resin (A), a colorant and a wax, wherein the toner particles contain the resin (B) in a specific amount with respect to the core, and wherein the solubility parameter (SP value) of the binder resin (A) is denoted by SP(A), the SP value of the resin (B) is denoted by SP(B), the SP value of a repeating unit with the smallest SP value from among repeating units constituting the resin (B) is denoted by SP(C), and the SP value of the wax is denoted by SP(W), each of the SP(A), SP(B), SP(C) and SP(W) satisfy specific relationships.

Provided is a toner having an excellent low-temperature fixability and hot offset resistance, a broad fixing temperature latitude in low-temperature areas to high-temperature areas, and a high heat-resistant storage stability. The toner includes toner particles having a core-shell structure in which a shell phase containing a resin A is formed on a core containing a binder resin, a colorant and a wax. In measurement of resin A by a differential scanning calorimetry (DSC), the peak temperature TpA (&#xb0; C.) of a maximum endothermic peak in the first temperature rise is at least 55&#xb0; C. but not more than 80&#xb0; C. In measurement of a viscoelasticity of resin A, the loss elastic modulus at TpA&#x2212;10 (&#xb0; C.) is at least 1&#xd7;10Pa but not more than 1&#xd7;10Pa. In measurement of the viscoelasticity of resin A, the loss elastic moduli at TpA (&#xb0; C.), TpA+10 (&#xb0; C.) and TpA+25 (&#xb0; C.) satisfy specific conditions.

In differential scanning calorimetry of a toner, regarding a binder resin in the toner, (i) the peak temperature Tof a maximum endothermic peak (temperature raising rate 10.0&#xb0; C./min; P) is 50&#xb0; C. to 80&#xb0; C. and the half-width Wis 2.0&#xb0; C. to 3.5&#xb0; C. and (ii) W, W, and Wsatisfy that W/Wis 0.20 to 1.00 and W/Wis 1.00 to 1.50, where the half-width of a maximum endothermic peak (temperature raising rate of 1.0&#xb0; C./min; P) is represented by W(&#xb0; C.) and the half-width of a maximum endothermic peak (temperature raising rate of 20.0&#xb0; C./min; P) is represented by W(&#xb0; C.).

Provided is a toner comprising a toner particle having a core-shell structure in which a shell phase containing a resin A is formed on a core that contains a binder resin, a colorant and a wax, wherein the resin A is a vinyl resin prepared by copolymerizing a vinyl monomer X that has an organopolysiloxane structure and a vinyl monomer Y that has a polyester segment capable of forming a crystalline structure; the content of the vinyl monomer X in a total monomer used for the copolymerization is in a particular range; the toner particle contains resin A in a particular proportion; and the binder resin contains a crystalline resin.

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Wako, Japan

Ayako Okamoto