Electrostatic charge image developing toner, electrostatic charge image developer, toner cartridge, developer cartridge, process cartridge, image forming method, and image forming apparatus
View Patent ↗An electrostatic charge image developing toner includes toner particles containing a colorant, a binder resin, and a release agent, and an external additive, wherein the external additive includes particles having oil-treated surfaces and composite particles containing silica and titania, and the toner has a content ratio of titania with respect to silica on the surface of the toner, as measured by X-ray photoelectron spectroscopy, of equal to or less than 5 atomic %.
1. An electrostatic charge image developing toner, comprising:
toner particles containing a colorant, a binder resin, and a release agent; and
an external additive,
wherein
the external additive includes particles having oil-treated surfaces and composite particles having a titania core and a silica coating layer, the composite particles having a volume average primary particle diameter in a range of from 60 nm to 500 nm, and
the toner has a content ratio of titania with respect to silica on a surface of the toner particles, as measured by X-ray photoelectron spectroscopy, of equal to or less than 5 atomic %.
2. The electrostatic charge image developing toner according to claim 1 , wherein a content of titania with respect to silica in the entire toner is in a range of 10% by weight to 50% by weight.
3. The electrostatic charge image developing toner according to claim 1 , wherein the content ratio of titania with respect to silica on the surface of the toner particles is in a range of 0.1 atomic % to 5 atomic %.
4. The electrostatic charge image developing toner according to claim 1 , wherein a weight ratio of the particles having oil-treated surfaces to the composite particles having a titania core and a silica coating layer is in a range of 10:1 to 1:10.
5. The electrostatic charge image developing toner according to claim 1 , wherein a weight ratio of the particles having oil-treated surfaces to the composite particles having a titania core and a silica coating layer is in a range of 5:1 to 1:5.
6. The electrostatic charge image developing toner according to claim 1 , wherein the oil is selected from a silicone oil, an aliphatic amide, and a wax.
7. The electrostatic charge image developing toner according to claim 1 , wherein a volume average primary particle diameter of the particles having oil-treated surfaces is in a range of 3 nm to 500 nm.
8. An electrostatic charge image developer comprising:
the toner according to claim 1 ; and
a carrier.
9. The electrostatic charge image developer according to claim 8 , wherein the toner has a weight ratio of the particles having oil-treated surfaces to the composite particles having a titania core and a silica coating layer in a range of 10:1 to 1:10.
10. A toner cartridge, comprising:
a toner containing chamber that contains the electrostatic charge image developing toner according to claim 1 .
11. A developer cartridge, comprising:
a developer containing chamber that contains the electrostatic charge image developer according to claim 8 .
12. A process cartridge for an image forming apparatus comprising:
a developer holding member that holds and transports an electrostatic charge image developer,
wherein the developer is the electrostatic charge image developer according to claim 8 .
13. The process cartridge for an image forming apparatus according to claim 12 , wherein the toner has a weight ratio of the particles having oil-treated surfaces to the composite particles having a titania core and a silica coating layer in a range of 10:1 to 1:10.
14. An image forming apparatus comprising:
an image holding member;
a charging unit that charges a surface of the image holding member;
an electrostatic latent image forming unit that forms an electrostatic latent image on the surface of the image holding member;
a development unit that contains the electrostatic charge image developer according to claim 8 , and develops the electrostatic latent image formed on the surface of the image holding member using the developer to form a toner image; and
a transfer unit that transfers the formed toner image onto a recording member.
15. The image forming apparatus according to claim 14 , wherein the toner has a weight ratio of the particles having oil-treated surfaces to the composite particles having a titania core and a silica coating layer in a range of 10:1 to 1:10.
16. An image forming method comprising:
charging a surface of an image holding member;
forming an electrostatic latent image on the surface of the image holding member;
developing the electrostatic latent image formed on the surface of the image holding member using the electrostatic charge image developer according to claim 8 to form a toner image; and
transferring the formed toner image onto a recording member.
17. The image forming method according to claim 16 , wherein the toner has a weight ratio of the particles having oil-treated surfaces to the composite particles having a titania core and a silica coating layer in a range of 10:1 to 1:10.
18. The electrostatic charge image developing toner according to claim 1 , wherein a treatment amount of oil is equal to or more than 0.16% by weight with respect to a total weight of the toner.