Electrophotographic photoreceptor, process cartridge, and image forming apparatus

1. An electrophotographic photoreceptor comprising:

a conductive substrate; and

a photosensitive layer on the conductive substrate, wherein:

the electrophotographic photoreceptor has an outermost surface layer that contains fluorine-containing resin particles and a fluorine-containing graft polymer,

fluorine-containing resin particles contain 0 or more and 30 or less carboxy groups per 10 6 carbon atoms,

outermost surface layer has a dielectric constant of 3.75 or more and 3.90 or less, and

a contact angle of pure water on the outermost surface layer is 90° or more.

2. The electrophotographic photoreceptor according to claim 1 , wherein the outermost surface layer has a dielectric constant of 3.80 or more and 3.90 or less, and the contact angle of pure water on the outermost surface layer is 95° or more.

3. An electrophotographic photoreceptor comprising:

a conductive substrate; and

a photosensitive layer on the conductive substrate,

wherein:

the electrophotographic photoreceptor has an outermost surface layer that contains fluorine-containing resin particles, a fluorine-containing graft polymer, and a defoaming agent,

the fluorine-containing resin particles contain 0 or more and 30 or less carboxy groups per 10 6 carbon atoms,

an amount of the fluorine-containing graft polymer relative to an amount of the fluorine-containing resin particles is 4.5 mass % or more and 9.0 mass % or less,

an amount of the defoaming agent relative to the outermost surface layer is 10 ppm or more and 10000 ppm or less,

the outermost surface layer has a dielectric constant of 3.75 or more and 3.90 or less, and

a contact angle of pure water on the outermost surface layer is 90° or more.

4. The electrophotographic photoreceptor according to claim 3 , wherein the defoaming agent is at least one defoaming agent selected from a silicone defoaming agent and a fluorine defoaming agent.

5. The electrophotographic photoreceptor according to claim 4 , wherein the defoaming agent is dimethylpolysiloxane.

6. The electrophotographic photoreceptor according to claim 3 , wherein the amount of the defoaming agent relative to the amount of the fluorine-containing resin particles is 0.01 mass % or more and 15 mass % or less.

7. The electrophotographic photoreceptor according to claim 4 , wherein the amount of the defoaming agent relative to the amount of the fluorine-containing resin particles is 0.01 mass % or more and 15 mass % or less.

8. The electrophotographic photoreceptor according to claim 5 , wherein the amount of the defoaming agent relative to the amount of the fluorine-containing resin particles is 0.01 mass % or more and 15 mass % or less.

9. The electrophotographic photoreceptor according to claim 3 , wherein the amount of the defoaming agent relative to the outermost surface layer is 100 ppm or more and 5000 ppm or less.

10. The electrophotographic photoreceptor according to claim 4 , wherein the amount of the defoaming agent relative to the outermost surface layer is 100 ppm or more and 5000 ppm or less.

11. The electrophotographic photoreceptor according to claim 5 , wherein the amount of the defoaming agent relative to the outermost surface layer is 100 ppm or more and 5000 ppm or less.

12. The electrophotographic photoreceptor according to claim 6 , wherein the amount of the defoaming agent relative to the outermost surface layer is 100 ppm or more and 5000 ppm or less.

13. The electrophotographic photoreceptor according to claim 7 , wherein the amount of the defoaming agent relative to the outermost surface layer is 100 ppm or more and 5000 ppm or less.

14. The electrophotographic photoreceptor according to claim 8 , wherein the amount of the defoaming agent relative to the outermost surface layer is 100 ppm or more and 5000 ppm or less.

15. A process cartridge detachably attachable to an image forming apparatus, the process cartridge comprising the electrophotographic photoreceptor according to claim 1 .

16. The process cartridge according to claim 15 , further comprising:

a cleaning unit that has a cleaning blade that contacts a surface of the electrophotographic photoreceptor to clean the electrophotographic photoreceptor,

wherein:

the cleaning blade has a contact portion that contacts the electrophotographic photoreceptor, and

the contact portion is constituted by a member in which a ratio (EIT/Re) of an indentation modulus (EIT [MPa]) to a rebound resilience (Re [%]) is 0.65 or more, and the rebound resilience (Re [%]) is 25% or more.

17. An image forming apparatus comprising:

the electrophotographic photoreceptor according to claim 1 ;

a charging unit that charges a surface of the electrophotographic photoreceptor;

an electrostatic latent image forming unit that forms an electrostatic latent image on the charged surface of the electrophotographic photoreceptor;

a developing unit that develops the electrostatic latent image on the surface of the electrophotographic photoreceptor by using a developer that contains a toner so as to form a toner image; and

a transfer unit that transfers the toner image onto a surface of a recording medium.

18. The image forming apparatus according to claim 17 , further comprising:

a cleaning unit that has a cleaning blade that contacts a surface of the electrophotographic photoreceptor to clean the electrophotographic photoreceptor,

wherein:

the cleaning blade has a contact portion that contacts the electrophotographic photoreceptor, and

the contact portion is constituted by a member in which a ratio (EIT/Re) of an indentation modulus (EIT [MPa]) to a rebound resilience (Re [%]) is 0.65 or more, and the rebound resilience (Re [%]) is 25% or more.