Fixing member, method for producing the same, fixing apparatus, and electrophotographic image forming apparatus
A fixing member having a base layer and a surface layer, wherein the surface layer includes a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and having at least one pore communicating with an opening on an outer surface thereof. A composition containing perfluoropolyether and a fluoropolymer is contained in at least a part of the at least one pore. The fluoropolymer has a particular repeating unit composed of perfluoropolyether, and at least one structure selected from the group consisting of a T unit of siloxane and a Q unit of siloxane.
1 . A fixing member comprising a base layer and a surface layer,
the surface layer containing a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and having at least one pore communicating with an opening on an outer surface thereof,
a composition containing perfluoropolyether and a fluoropolymer being contained in at least a part of the at least one pore, wherein
the fluoropolymer has
a repeating unit represented by the following structural formula (1), and
at least one unit selected from the group consisting of a T unit of siloxane and a Q unit of siloxane:
wherein n represents a positive integer,
wherein the perfluoropolyether has a structure represented by the following structural formula (2):
wherein a, b, c, d, e and f each independently represent 0 or a positive integer, and satisfy 1≤a+b+c+d+e+f≤600; and at least one of a, b, c and d is a positive integer.
2 . The fixing member according to claim 1 , wherein the perfluoropolyether has at least one structure selected from the group consisting of the following structural formulae (3) to (6):
wherein n represents a positive integer, and n is a number in a range in which the viscosity of the perfluoropolyether at a temperature of 40° C. is in a range of 30 mPa·s to 500 mPa·s;
wherein n′ represents a positive integer, and n′ is a number in a range in which the viscosity of the perfluoropolyether at a temperature of 40° C. is in a range of 10 mPa·s to 2500 mPa·s;
wherein m and n″ each independently represent a positive integer, m/n″ is a number of 0.5 or larger and 2 or smaller, and m+n” is a number in a range in which the viscosity of the perfluoropolyether at a temperature of 40° C. is in a range of 20 mPa·s to 1400 mPa·s; and
wherein m′ and n″ each independently represent a positive integer, m′/n″ is a number of 20 or larger and 1000 or smaller, and m′+n″ is a number in a range in which the viscosity of the perfluoropolyether at a temperature of 40° C. is in a range of 20 mPa·s to 1200 mPa·s.
3 . The fixing member according to claim 1 , having an endless belt shape, wherein a ratio (porosity) of an area occupied by the at least one pore to an area including a portion of the at least one pore, in a cross section along a circumferential direction of the fixing member of the surface layer is 25.0% or more and 60.0% or less.
4 . The fixing member according to claim 1 , wherein the content ratio of the composition contained in the at least one pore to the total mass of the surface layer including the mass of the composition is 20% by mass or more and 60% by mass or less.
5 . The fixing member according to claim 1 , wherein a content ratio (mass ratio) of the perfluoropolyether in the composition is 0.20 or more and 0.80 or less.
6 . The fixing member according to claim 1 , wherein a viscosity of the perfluoropolyether at 40° C. is 1000 mPa·s or higher and 2500 mPa·s or lower.
7 . The fixing member according to claim 1 , wherein an average opening diameter of the openings on a first surface constituting the outer surface of the surface layer is 1 nm or larger and 5 μm or smaller.
8 . The fixing member according to claim 1 , wherein an opening ratio on the first surface constituting the outer surface of the surface layer is 1.0% or larger and 15.0% or smaller.
9 . The fixing member according to claim 1 , wherein a thickness of the surface layer is 10 μm or larger and 100 μm or smaller.
10 . A fixing apparatus comprising: a fixing member comprising a base layer and a surface layer; and a heating unit for heating the fixing member, wherein
the surface layer contains a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and having at least one pore communicating with an opening on an outer surface thereof,
a composition containing perfluoropolyether and a fluoropolymer is contained in at least a part of the at least one pore,
wherein the fluoropolymer has a repeating unit represented by the following structural formula (1), and at least one structure selected from the group consisting of a T unit of siloxane and a Q unit of siloxane:
wherein n represents a positive integer,
wherein the perfluoropolyether has a structure represented by the following structural formula (2):
wherein a, b, c, d, e and f each independently represent 0 or a positive integer, and satisfy 1≤a+b+c+d+e+f≤600; and at least one of a, b, c and d is a positive integer.
11 . The fixing apparatus according to claim 10 , wherein the fixing member is a fixing belt having an endless belt shape, and the heating unit is a heater arranged in contact with an inner peripheral surface of the fixing belt.
12 . An electrophotographic image forming apparatus comprising a fixing apparatus comprising: a fixing member comprising a base layer and a surface layer; and a heating unit for heating the fixing member, wherein
the surface layer contains a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and having at least one pore communicating with an opening on an outer surface thereof,
a composition containing perfluoropolyether and a fluoropolymer is contained in at least a part of the at least one pore,
wherein the fluoropolymer has a repeating unit represented by the following structural formula (1), and at least one structure selected from the group consisting of a T unit of siloxane and a Q unit of siloxane:
wherein n represents a positive integer,
wherein the perfluoropolyether has a structure represented by the following structural formula (2):
wherein a, b, c, d, e and f each independently represent 0 or a positive integer, and satisfy 1≤a+b+c+d+e+f≤600; and at least one of a, b, c and d is a positive integer.