Electrophotographic photosensitive member, method for producing the same, process cartridge and electrophotographic apparatus

1. An electrophotographic photosensitive member comprising:

a support; and

a photosensitive layer on the support, wherein

a surface layer of the electrophotographic photosensitive member comprises a copolymerized product of a hole transporting compound having an acryloyloxy group or a methacryloyloxy group and having a triphenylamine backbone, and a compound represented by formula (1) or formula (2):

where m 1 represents 2 and X 1 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 2 to 18 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 12 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 12 carbon atoms, provided that the number of carbon atoms in X 1 is 2 to 18; and

where m 2 represents 1, m 3 represents 1, and Y 1 represents an oxygen atom or a sulfur atom,

X 2 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 1 to 15 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and

X 3 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 1 to 15 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms, unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and an arene having 6 to 12 carbon atoms, unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms,

provided that the total number of carbon atoms in X 2 and X 3 is 2 to 16.

2. The electrophotographic photosensitive member according to claim 1 , wherein X 1 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 2 to 18 carbon atoms, and a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 12 carbon atoms,

X 2 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 1 to 15 carbon atoms, and a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and

X 3 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 1 to 15 carbon atoms, and a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms.

3. The electrophotographic photosensitive member according to claim 1 , wherein X 1 represents a 2-valent group obtained by removing 2 hydrogen atoms from a linear or branched alkane having 2 to 18 carbon atoms,

X 2 represents a 2-valent group obtained by removing 2 hydrogen atoms from a linear or branched alkane having 1 to 15 carbon atoms, and

X 3 represents a 2-valent group obtained by removing 2 hydrogen atoms from a linear or branched alkane having 1 to 15 carbon atoms.

4. The electrophotographic photosensitive member according to claim 1 , wherein X 1 represents a 2-valent group obtained by removing 2 hydrogen atoms from a linear or branched alkane having 2 6 carbon atoms,

X 2 represents a 2-valent group obtained by removing 2 hydrogen atoms from a linear or branched alkane having 1 to 3 carbon atoms, and

X 3 represents a 2-valent group obtained by removing 2 hydrogen atoms from a linear or branched alkane having 1 3 carbon atoms,

provided that the total number of carbon atoms in X 2 and X 3 is 2 to 4.

5. The electrophotographic photosensitive member according to claim 1 , wherein the hole transporting compound having a triphenylamine backbone is a compound represented by formula (3):

(P 1 a Z  (3)

where P 1 represents a group represented by formula (4) or formula (5); “a” represents an integer of 2 to 4, and P 1 s may be the same or different; Z represents a hole transporting group, and a hydrogenated product in which a binding moiety of Z and P 1 is replaced with a hydrogen atom is a compound represented by formula (6) or formula (7):

where R 4 , R 5 and R 6 represent a phenyl group which may have an alkyl group having 1 to 6 carbon atoms as a substituent; and R 4 , R 5 and R 6 may be each the same or different; and

where R 7 , R 8 , R 9 and R 10 represent a phenyl group which may have an alkyl group having 1 to 6 carbon atoms as a substituent; and R 7 , R 8 , R 9 and R 10 may be each the same or different.

6. The electrophotographic photosensitive member according to claim 1 , wherein 0.05≤Mb/(Ma+Mb)≤0.50 when content mass of the hole transporting compound contained in the surface layer is designated as Ma and content mass of the compound represented by formula (1) or formula (2) contained in the surface layer is designated as Mb.

7. A method for producing an electrophotographic photosensitive member comprising a support and a surface layer on the support, the method comprising:

preparing a coating liquid for a surface layer, the coating liquid comprising a hole transporting compound having an acryloyloxy group or a methacryloyloxy group and having a triphenylamine backbone, and a compound represented by formula (1) or formula (2), and

forming a coating film of the coating liquid for a surface layer, and curing the coating film to thereby form a surface layer:

where m 1 represents 2 and X 1 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 2 to 18 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 12 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 12 carbon atoms, provided that the number of carbon atoms in X 1 is 2 to 18; and

where m 2 represents 1, m 3 represents 1, and Y 1 represents an oxygen atom or a sulfur atom,

X 2 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 1 to 15 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and

X 3 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 1 to 15 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms,

provided that the total number of carbon atoms in X 2 and X 3 is 2 to 16.

8. A process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge integrally supporting:

an electrophotographic photosensitive member, and

at least one unit selected from the group consisting of a charging unit that charges the electrophotographic photosensitive member, a developing unit that develops an electrostatic latent image formed on a surface of the electrophotographic photosensitive member, by a toner, to form a toner image on the surface of the electrophotographic photosensitive member, a transferring unit that transfers the toner image from the surface of the electrophotographic photosensitive member to a transfer material, and a cleaning unit that cleans the surface of the electrophotographic photosensitive member, the electrophotographic photosensitive member comprising:

a support, and

a photosensitive layer on the support; and

a surface layer of the electrophotographic photosensitive member comprising a copolymerized product of a hole transporting compound having an acryloyloxy group or a methacryloyloxy group and having a triphenylamine backbone, and a compound represented by formula (1) or formula (2):

where m 1 represents 2 and X 1 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 2 to 18 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 12 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 12 carbon atoms, provided that the number of carbon atoms in X 1 is 2 to 18; and

where m 2 represents 1, m 3 represents 1, and Y 1 represents an oxygen atom or a sulfur atom,

X 2 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 1 to 15 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and

X 3 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 1 to 15 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms,

provided that the total number of carbon atoms in X 2 and X 3 is 2 to 16.

9. An electrophotographic apparatus comprising:

an electrophotographic photosensitive member, and

a charging unit that charges the electrophotographic photosensitive member,

an exposure unit that irradiates a surface of the electrophotographic photosensitive member with exposure light to form an electrostatic latent image on the surface of the electrophotographic photosensitive member,

a developing unit that develops the electrostatic latent image by a toner to form a toner image on the surface of the electrophotographic photosensitive member, and

a transferring unit that transfers the toner image from the surface of the electrophotographic photosensitive member to a transfer material, the electrophotographic photosensitive member comprising:

a support, and

a photosensitive layer on the support, wherein

a surface layer of the electrophotographic photosensitive member comprises a copolymerized product of a hole transporting compound having an acryloyloxy group or a methacryloyloxy group and having a triphenylamine backbone, and a compound represented by formula (1) or formula (2):

where m 1 represents 2 and X 1 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 2 to 18 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 12 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 12 carbon atoms, provided that the number of carbon atoms in X 1 is 2 to 18; and

where m 2 represents 1, m 3 represents 1, and Y 1 represents an oxygen atom or a sulfur atom,

X 2 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 1 to 15 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and

X 3 represents a 2-valent group obtained by removing 2 hydrogen atoms from any of a linear or branched alkane having 1 to 15 carbon atoms, a cyclic or polycyclic alkane having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms, and an arene having 6 to 12 carbon atoms unsubstituted or having a linear or branched alkyl group having 1 to 9 carbon atoms,

provided that the total number of carbon atoms in X 2 and X 3 is 2 to 16.