Electrophotographic member, fixing apparatus and electrophotographic image forming apparatus
An electrophotographic member comprising: at least a base layer; an elastic layer; and a surface layer in this order, wherein the surface layer comprises a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, at an endothermic curve upon performing two measurements at a ramp up rate and a ramp down rate both set at 20° C./min using a differential scanning calorimeter (DSC) with a sample sampled from the surface layer as a measurement sample, an endothermic peak temperature in a second temperature raising process is 304° C. or less, an endothermic quantity in a first temperature raising process is 21J/g or more, and D3 is 40 μm or less, where D3 represents an area average diameter of a spherulite at an outer surface of the surface layer.
1 . An electrophotographic member comprising:
at least a base layer; an elastic layer; and a surface layer in this order, wherein
the surface layer comprises a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer,
at an endothermic curve upon performing two measurements at a ramp up rate and a ramp down rate both set at 20° C./min using a differential scanning calorimeter (DSC) with a sample sampled from the surface layer as a measurement sample,
an endothermic peak temperature in a second temperature raising process is 304° C. or less,
an endothermic quantity in a first temperature raising process is 21 J/g or more,
D3 is 40 μm or less, where D3 represents an area average diameter of a spherulite at an outer surface of the surface layer, and
D3/D1 is 1.5 or less, where D1 represents a number-average diameter of the spherulite at the outer surface of the surface layer.
2 . The electrophotographic member according to claim 1 , wherein an arithmetic average roughness Ra of an outer surface of the surface layer is 0.20 μm or less.
3 . The electrophotographic member according to claim 1 , wherein the D3 is 5 μm to 40 μm.
4 . The electrophotographic member according to claim 1 , wherein the endothermic quantity in the first temperature raising process is 21 J/g to 27 J/g.
5 . The electrophotographic member according to claim 1 , wherein the endothermic peak temperature in the second temperature raising process is 297° C. to 304° C.
6 . The electrophotographic member according to claim 1 , wherein the endothermic peak temperature in the second temperature raising process is 300° C. to 304° C.
7 . The electrophotographic member according to claim 1 , wherein C-F/2-O≥30 is satisfied, where C at % represents a carbon element ratio at a surface of the surface layer opposed to the elastic layer, F at % represents a fluorine element ratio thereof, and O at % represents an oxygen element ratio thereof.
8 . The electrophotographic member according to claim 1 , wherein a thickness of the surface layer is 30 μm or less.
9 . The electrophotographic member according to claim 1 , wherein a thickness of the surface layer is 10 μm to 30 μm.
10 . The electrophotographic member according to claim 1 , wherein the electrophotographic member is an electrophotographic belt having an endless shape.
11 . The electrophotographic member according to claim 10 , wherein the electrophotographic member is a fixing belt.
12 . A fixing apparatus in an electrophotographic image forming apparatus, the fixing apparatus comprising:
a fixing member; and
a pressurizing member arranged opposed to the fixing member,
wherein at least one of the fixing member and the pressurizing member is the electrophotographic member according to claim 1 .
13 . An electrophotographic image forming apparatus comprising a fixing apparatus, wherein
the fixing apparatus includes a fixing member, and a pressurizing member arranged opposed to the fixing member, and
at least one of the fixing member and the pressurizing member is the electrophotographic member according to claim 1 .