Charging member

1. A charging member comprising:

a conductive support;

a conductive elastomer layer stacked on the conductive support; and

a conductive resin layer stacked on the conductive elastomer layer,

wherein the conductive resin layer comprises:

a matrix material; and

a plurality of particles dispersed in the matrix material,

wherein, the plurality of particles comprise first particles, and

when a thickness of a portion formed of the matrix material alone of the conductive resin layer is referred to as A [μm], an average particle size of the first particles is referred to as B 1 [μm], and an interparticle distance of the particles is referred to as Sm [μm], then

A is in a range of 1.0 μm to 7.0 μm,

B 1 /A is in a range of 5.0 to 30.0, and

Sm is in a range of 50 μm to 400 μm.

2. The charging member of claim 1 , wherein a thickness of the conductive resin layer is in a range of 1.0 μm to 5.0 μm.

3. The charging member of claim 1 , wherein B 1 /A is in a range of 7.5 to 20.0.

4. The charging member of claim 1 , wherein a 10-point average roughness (RzJIS) of the conductive resin layer is in a range of 10.0 μm to 35.0 μm.

5. The charging member of claim 1 , wherein a content of the particles is in a range of 5 wt % to 50 wt % based on the total weight of the conductive resin layer.

6. The charging member of claim 1 , wherein B 1 is in a range of 5.0 μm to 50.0 μm.

7. The charging member of claim 1 , wherein the particles further comprise second particles, and when an average particle size of the second particles is referred to as B 2 [μm],

B 1 is in a range of 15.0 μm to 40.0 μm, and

B 1 -B 2 is 10.0 μm or greater.

8. The charging member of claim 7 , wherein a weight ratio of the first particles and the second particles is in a range of 5:1 to 1:5.

9. The charging member of claim 1 , wherein the particles comprise insulating particles.

10. The charging member of claim 1 , wherein the particles comprise irregular-shaped particles.

11. The charging member of claim 1 , wherein the particles comprise resin particles.

12. The charging member of claim 11 , wherein the resin particles comprise at least one type of particles selected from the group consisting of nylon resin particles and acryl resin particles.

13. The charging member of claim 1 , wherein the matrix material comprises at least one type of resin selected from the group consisting of a nylon resin and a polyurethane resin.

14. The charging member of claim 1 , wherein the conductive elastomer layer comprises epichlorohydrin rubber.

15. The charging member of claim 1 , wherein a thickness of the conductive elastomer layer is in a range of 1.25 mm to 3.00 mm.

16. The charging member of claim 1 , wherein an AskerC hardness of the charging member is 78±4.

17. The charging member of claim 1 , wherein, when a load applied to an end part of the conductive support is in a range of 5.0 N to 8.0 N, the charging member has a crown amount in a range of 60 μm to 120 μm.

18. The charging member of claim 1 , wherein, when an electrical resistance value of the charging member, which is measured by using a metal roll electrode method, is referred to as R, a log R value is 5.4±0.4.

19. The charging member of claim 1 , to which only a direct current (DC) voltage is applied, wherein a bias voltage applied thereto is in a range of −1000 V to −1500 V.

20. An electrophotographic image forming device comprising:

a main body;

an image carrier; and

a charging member for charging the image carrier,

wherein the charging member is a charging member according to claim 1 .

21. The charging member of claim 1 , wherein A is in a range of 1.0 μm to 4.0 μm.