Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus
Provided is an electrophotographic photosensitive member having a satisfactory chargeability and being excellent in fogging suppression. The electrophotographic photosensitive member is an electrophotographic photosensitive member including a surface protective layer, wherein the surface protective layer is a polymerized film of a composition containing a compound having one of an acryloyloxy group or a methacryloyloxy group, a conductive particle, and an organic salt formed of at least one organic cation selected from the group consisting of: imidazolium; pyridinium; pyrrolidinium; piperidinium; a tetraalkylammonium; and a tetraalkylphosphonium, and at least one anion selected from the group consisting of organic or inorganic anions, and wherein the content of the organic salt is 0.1 mass % to 10.0 mass % with respect to the total mass of the conductive particle.
1. An electrophotographic photosensitive member comprising a surface protective layer:
the surface protective layer being a polymerized film of a composition comprising (i) a compound having one of an acryloyloxy group or a methacryloyloxy group, (ii) a conductive particle and (iii) an organic salt;
the conductive particle being a titanium oxide particle containing niobium;
the organic salt being formed of at least one organic cation and at least one anion;
the organic cation being selected from the group consisting of imidazolium, pyridinium, pyrrolidinium, piperidinium, a tetraalkylammonium and a tetraalkylphosphonium; and
the anion being selected from the group consisting of an organic anion and an inorganic anion, wherein
a content of the organic salt is 0.1 to 10.0 mass % with respect to a total mass of the conductive particle, and
a content of the niobium in the conductive particle is 2.6 to 10.0 mass % with respect to a total mass of the conductive particle.
2. The electrophotographic photosensitive member according to claim 1 , wherein the organic salt is represented by any one of formulae (A) to (E)
when R a1 , R a2 , R b1 , R b2 , R b3 , R e1 , R e2 , R d1 , R d2 , R e1 and R e2 independently represent an alkylene group having 8 or less carbon atoms,
R a3 , R d3 , R d4 , R e3 and R e4 independently represent a hydrogen atom or an alkyl group having 8 or less carbon atoms,
Z a1 , Z a2 , z b1 , z b2 , z b3 , z e1 , z e2 , z d1 , z d2 , z e1 and Z e2 independently represent a functional group selected from the group consisting of a hydrogen atom, a cyano group, an acryloyloxy group, a methacryloyloxy group and a vinyl group, and
X − s independently represent an anion selected from the group consisting of Cl − , Br − , I − , R f1 COO where R f1 represents an alkyl group or a perfluoroalkyl group having 3 or less carbon atoms, R f2 PO 4 − where R f2 represents an alkyl group having 4 or less carbon atoms, R f3 SO 4 − where R f3 represents an alkyl group having 8 or less carbon atoms, R f4 SO 3 − where R f4 represents an alkyl group or a perfluoroalkyl group having 4 or less carbon atoms, (R f5 SO 2 )N − where R f5 represents F or a perfluoroalkyl group having 2 or less carbon atoms, R f6 BF 2 where R f6 represents F or a trifluoromethyl group, SCN − and (CN) 2 N − , and n represents 1 or 2.
3. The electrophotographic photosensitive member according to claim 1 , wherein the polymerized film contains a polymerization product of a composition containing the organic salt.
4. The electrophotographic photosensitive member according to claim 1 , wherein the electrophotographic photosensitive member comprises a support, a charge-generating layer, a charge-transporting layer and the surface protective layer, in this order.
5. A process cartridge, comprising:
an electrophotographic photosensitive member comprising a surface protective layer; and
at least one unit selected from the group consisting of a charging unit, a developing unit and a cleaning unit;
the process cartridge integrally supporting the electrophotographic photosensitive member and the at least one unit, and being removably mounted onto a main body of an electrophotographic apparatus;
the surface protective layer being a polymerized film of a composition comprising (i) a compound having one of an acryloyloxy group or a methacryloyloxy group, (ii) a conductive particle and (iii) an organic salt;
the conductive particle being a titanium oxide particle containing niobium;
the organic salt being formed of at least one organic cation and at least one anion;
the organic cation being selected from the group consisting of imidazolium, pyridinium, pyrrolidinium, piperidinium, a tetraalkylammonium and a tetraalkylphosphonium; and
the anion being selected from the group consisting of an organic anion and an inorganic anion, wherein
a content of the organic salt is 0.1 to 10.0 mass % with respect to a total mass of the conductive particle, and
a content of the niobium in the conductive particle is 2.6 to 10.0 mass % with respect to a total mass of the conductive particle.
6. An electrophotographic apparatus, comprising:
an electrophotographic photosensitive member comprising a surface protective layer;
a charging unit;
an exposing unit;
a developing unit; and
a transferring unit;
the surface protective layer being a polymerized film of a composition comprising (i) a compound having one of an acryloyloxy group or a methacryloyloxy group, (ii) a conductive particle and (iii) an organic salt;
the conductive particle being a titanium oxide particle containing niobium;
the organic salt being formed of at least one organic cation and at least one anion;
the organic cation being selected from the group consisting of imidazolium, pyridinium, pyrrolidinium, piperidinium, a tetraalkylammonium and a tetraalkylphosphonium; and
the anion being selected from the group consisting of an organic anion and an inorganic anion, wherein
a content of the organic salt is 0.1 to 10.0 mass % with respect to a total mass of the conductive particle, and
a content of the niobium in the conductive particle is 2.6 to 10.0 mass % with respect to a total mass of the conductive particle.