Electrostatic charge image development toner, electrostatic charge image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method

1. An electrostatic charge image development toner that is negatively chargeable, comprising:

toner particles; and

layered-structure compound particles,

wherein the layered-structure compound particles have a volume-average particle diameter Da of 0.4 μm or more and less than 3.0 μm, and

a ratio Da/Db of the volume-average particle diameter Da of the layered-structure compound particles to a volume-average particle diameter Db of the toner particles is 0.044 or more and 0.625 or less.

2. The electrostatic charge image development toner according to claim 1 , wherein the toner particles have a volume-average particle diameter Db of 4 μm or more and 9 μm or less.

3. The electrostatic charge image development toner according to claim 2 , wherein an amount of the layered-structure compound particles is 0.01 mass % or more and 1.0 mass % or less relative to the entire electrostatic charge image development toner.

4. The electrostatic charge image development toner according to claim 3 , wherein the ratio Da/Db of the volume-average particle diameter Da of the layered-structure compound particles to the volume-average particle diameter Db of the toner particles is 0.056 or more and 0.580 or less.

5. The electrostatic charge image development toner according to claim 2 , wherein the ratio Da/DU of the volume-average particle diameter Da of the layered-structure compound particles to the volume-average particle diameter Db of the toner particles is 0.056 or more and 0.580 or less.

6. The electrostatic charge image development toner according to claim 2 , wherein the layered-structure compound particles have a volume-average particle diameter Da of 0.45 μm or more and 2.7 μm or less.

7. The electrostatic charge image development toner according to claim 2 , wherein the toner particles have a volume-average particle diameter Db of 4 μm or more and 8 μm or less.

8. The electrostatic charge image development toner according to claim 1 , wherein an amount of the layered-structure compound particles is 0.01 mass % or more and 1.0 mass % or less relative to the entire electrostatic charge image development toner.

9. The electrostatic charge image development toner according to claim 8 , wherein the amount of the layered-structure compound particles is 0.01 mass % or more and 0.90 mass % or less relative to the entire electrostatic charge image development toner.

10. The electrostatic charge image development toner according to claim 8 , wherein the layered-structure compound particles have a volume-average particle diameter Da of 0.45 μm or more and 2.7 μm or less.

11. The electrostatic charge image development toner according to claim 8 , wherein the ratio Da/Db of the volume-average particle diameter Da of the layered-structure compound particles to the volume-average particle diameter Db of the toner particles is 0.056 or more and 0.580 or less.

12. The electrostatic charge image development toner according to claim 1 , wherein the ratio Da/Db of the volume-average particle diameter Da of the layered-structure compound particles to the volume-average particle diameter Db of the toner particles is 0.056 or more and 0.580 or less.

13. The electrostatic charge image development toner according to claim 1 , wherein the layered-structure compound particles have a volume-average particle diameter Da of 0.45 μm or more and 2.7 μm or less.

14. The electrostatic charge image development toner according to claim 1 , wherein the layered-structure compound particles contain at least one type of particles selected from the group consisting of melamine cyanurate particles, boron nitride particles, graphite fluoride particles, molybdenum disulfide particles, and mica particles.

15. An electrostatic charge image developer comprising the electrostatic charge image development toner according to claim 1 .

16. A toner cartridge attachable to and detachable from an image forming apparatus, the toner cartridge comprising the electrostatic charge image development toner according to claim 1 .

17. The toner cartridge according to claim 16 , wherein the toner cartridge is a rotary toner cartridge having a rotary body containing the electrostatic charge image development toner.

18. A process cartridge attachable to and detachable from an image forming apparatus, the process cartridge comprising:

a developing unit that contains an electrostatic charge image developer and develops an electrostatic charge image on a surface of an image holding member by using the electrostatic charge image developer to form a toner image;

a toner cartridge that contains the electrostatic charge image development toner according to claim 1 ; and

a toner replenishment path that connects between the toner cartridge and the developing unit and through which the developing unit is replenished with the electrostatic charge image development toner in the toner cartridge.

19. An image forming apparatus comprising:

an image holding member;

a charging unit that charges a surface of the image holding member;

an electrostatic charge image forming unit that forms an electrostatic charge image on the charged surface of the image holding member;

a developing unit that contains an electrostatic charge image developer and develops an electrostatic charge image on the surface of the image holding member by using the electrostatic charge image developer to form a toner image;

a transfer it that transfers the toner image on the surface of the image holding member onto a surface of a recording medium;

a fixing unit that fixes the toner image that has been transferred onto the surface of the recording medium;

a replenishment toner container that contains the electrostatic charge image development toner according to claim 1 ; and

a toner replenishment path that connects between the replenishment toner container and the developing unit and through which the developing unit is replenished with the electrostatic charge image development toner in the replenishment toner container.

20. An image forming method comprising:

charging a surface of an image holding member;

forming an electrostatic charge image on the charged surface of the image holding member;

developing the electrostatic charge image on the surface of the image holding member by using an electrostatic charge image developer to form a toner image;

transferring the toner image on the surface of the image holding member onto a surface of a recording medium;

fixing the toner image that as been transferred onto the surface of the recording medium; and

replenishing a developing unit with the electrostatic charge image development toner according to claim 1 in a replenishment toner container from the replenishment toner container containing the electrostatic charge image development toner through a toner replenishment path that connects between the replenishment toner container and the developing unit.