Electrostatic charge image developing toner and method of producing the same, electrostatic charge image developer, toner cartridge, process cartridge, and image forming device
View Patent ↗A toner for developing an electrostatic charge image includes: an amorphous polyester resin; a crystalline polyester resin; and a releasing agent, an amount of the releasing agent in the toner being from 5 to 15% by weight; an amount of the releasing agent present at a surface of the toner being from 10 to 35% by weight; and the toner showing at least one endothermic peak in each of a temperature range from 45 to 60° C., a temperature range from 65 to 80° C., and a temperature range from 85 to 100° C. in a temperature-rise process of differential scanning calorimetry of the toner.
1. A method of producing a toner for developing an electrostatic charge image, the toner showing at least one first endothermic peak at a temperature range from about 45 to about 60° C., at least one second endothermic peak at a temperature range from about 65 to about 80° C., and at least one third endothermic peak at a temperature range from about 85 to about 100° C., the method comprising:
kneading a toner forming material comprising an amorphous polyester resin, a crystalline polyester resin, and a releasing agent to obtain a kneaded material;
cooling the kneaded material which has been formed by the kneading; and
pulverizing the kneaded material which has been cooled by the cooling,
the kneading comprising, with a temperature at which the third endothermic peak of the toner is generated being represented by Ta and a melting temperature of the amorphous polyester resin being represented by Tm, a first kneading in which the toner forming material is kneaded at a temperature from about Ta−10° C. to about Ta+10° C., and a second kneading in which the toner forming material which has been kneaded in the first kneading is kneaded at a temperature from about Tm−10° C. to about Tm+20° C.,
wherein
an amount of the releasing agent in the toner is from about 5 to about 15% by weight, and
an amount of the releasing agent present at a surface of the toner is from about 10 to about 35% by weight.
2. The method of producing a toner for developing an electrostatic charge image of claim 1 , wherein in the second kneading, an aqueous medium in an amount from about 0.5 to about 5 parts by weight is added to 100 parts by weight of the toner forming material.
3. The method of producing a toner for developing an electrostatic charge image of claim 1 , wherein in the cooling, the kneaded material is cooled to about 40° C. or less at an average temperature-decrease speed of about 4° C./sec or more.
4. The method of producing a toner for developing an electrostatic charge image of claim 1 , wherein in the pulverization, an inorganic oxide in an amount from about 0.1 to about 5 parts by weight is added to 100 parts by weight of the kneaded material.