Transparent toner for electrostatic latent image developing, electrostatic latent image developer, toner cartridge, process cartridge, image forming apparatus and image forming method
View Patent ↗A transparent toner for electrostatic latent image developing, including a binder resin and a release agent, the difference between Tm and Tc being from about 30° C. to about 50° C., wherein Tm is an endothermic peak temperature of the release agent determined in a temperature rising process and Tc is an exothermic peak temperature of the release agent determined in a temperature decreasing process, in a measurement by a differential scanning calorimeter (DSC) according an ASTM method, and the toner having a weight average molecular weight of from about 35,000 to about 70,000.
1. A transparent toner for electrostatic latent image developing, comprising a binder resin and a release agent,
the difference between Tm and Tc being from about 30° C. to about 50° C., wherein Tm is an endothermic peak temperature of the release agent determined in a temperature rising process and Tc is an exothermic peak temperature of the release agent determined in a temperature decreasing process, in a measurement by a differential scanning calorimeter (DSC) according an ASTM method,
the toner having a weight average molecular weight of from about 35,000 to about 70,000, and
Al being contained in a release agent domain of the toner.
2. The transparent toner for electrostatic latent image developing according to claim 1 , wherein the content of Al contained in the release agent domain is from about 0.005 atomic % to about 0.1 atomic %.
3. The transparent toner for electrostatic latent image developing according to claim 1 , wherein the content of the colorant in the toner is 0.01% by weight or less relative to the toner.
4. The transparent toner for electrostatic latent image developing according to claim 1 , wherein the binder resin is a polyester resin.
5. The transparent toner for electrostatic latent image developing according to claim 4 , wherein the polyester resin has a glass transition temperature (Tg) of from about 50° C. to about 80° C.
6. The transparent toner for electrostatic latent image developing according to claim 1 , wherein the release agent has a melting temperature of from about 60° C. to about 120° C.
7. The transparent toner for electrostatic latent image developing according to claim 1 , wherein the content of the release agent in the toner is from about 0.5% by weight to about 15% by weight relative to the toner.
8. The transparent toner for electrostatic latent image developing according to claim 1 , wherein the toner has a volume average particle size of from about 4μm to about 9 μm.
9. The transparent toner for electrostatic latent image developing according to claim 1 , wherein the toner has a shape factor SF1 of from about 110 to about 140.
10. The transparent toner for electrostatic latent image developing according to claim 1 , further comprising an external additive in an amount of from about 0.1 parts by weight to about 5 parts by weight per 100 parts by weight of toner particles.
11. An electrostatic latent image developer, comprising the transparent toner for electrostatic charge developing according to claim 1 .
12. The electrostatic latent image developer according to claim 11 , further comprising a carrier containing a white electro-conductive agent.
13. The electrostatic latent image developer according to claim 12 , wherein the white electro-conductive agent is zinc oxide or titanium oxide.
14. A toner cartridge configured to detachably attach to an image forming apparatus and containing a toner that is supplied to a developing unit in the image forming apparatus, wherein the toner is the transparent toner for electrostatic latent image developing according to claim 1 .
15. A process cartridge comprising a developer holder that contains the electrostatic latent image developer according to claim 11 .
16. An image forming apparatus comprising:
a latent image holding member;
a developing unit that contains the electrostatic latent image developer according to claim 11 and develops a latent image formed on the latent image holding member into a toner image using the electrostatic latent image developer;
a transfer unit that transfers the toner image formed on the latent image holding member onto a receiving member; and
a fixing unit that fixes the toner image that is transferred onto the receiving member.
17. An image forming method comprising:
forming an electrostatic latent image on a latent image holding member;
developing the latent image formed on the latent image holding member to form a toner image using the electrostatic latent image developer according to claim 11 contained in a developer holder;
transferring the toner image formed on the latent image holding member onto a receiving member; and
fixing the toner image transferred onto the receiving member,
wherein a shape factor SF1 of a release agent domain in the cross-section of the fixed toner image is from about 100 to about 140.