Electrostatic charge image developing toner, electrostatic charge image developer, toner cartridge, developing device, image forming apparatus, and image forming method

1. An electrostatic charge image developing toner comprising:

toner base particles which contain a polyester resin and a vinyl resin and does not have a coating layer and wherein the concentration of the polyester resin on the particle surface is higher than the concentration of the polyester resin in the inside of the particles; and

a sol-gel silica which has an average circularity of from 0.75 to 0.9, on the surface of the toner base particles,

wherein an average of a ratio of a circle-equivalent diameter (Da) of the sol-gel silica that is obtained by planer image analysis to a maximum height (H) of the sol-gel silica that is obtained by three-dimensional image analysis is from 1.5 to 1.9.

2. The electrostatic charge image developing toner according to claim 1 ,

wherein a volume average particle size of the sol-gel silica is from 70 nm to 200 nm.

3. An electrostatic charge image developer comprising at least the electrostatic charge image developing toner according to claim 1 .

4. A toner cartridge that accommodates the electrostatic charge image developing toner according to claim 1 and is detachable from an image forming apparatus.

5. A developing device comprising a developing member that accommodates the electrostatic charge image developing toner according to claim 1 and develops an electrostatic charge image formed on an image holding member as a toner image by using the electrostatic charge image developing toner.

6. An image forming apparatus comprising:

an image holding member;

a charging device that charges the image holding member;

an electrostatic charge image forming device that forms an electrostatic charge image on a surface of a charged image holding member;

a developing device that accommodates the electrostatic charge image developing toner according to claim 1 and develops the electrostatic charge image formed on the image holding member as a toner image by using the electrostatic charge image developing toner; and

a transfer device that transfers the toner image formed on the image holding member to a transfer medium.

7. An image forming method comprising:

charging an image holding member;

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

developing the electrostatic charge image formed on the image holding member as a toner image by using the electrostatic charge image developing toner according to claim 1 ; and

transferring the toner image formed on the image holding member to a transfer medium.