Electrophotographic component, fixing device, and electrophotographic image forming apparatus

Abstract

This electrophotographic component boasts high thermal conductivity and high durability, making it resistant to rupture of the elastic layer even under prolonged use under conditions where the maximum surface pressure of the fixing nip is greater than that of conventional components. [Solution] An electrophotographic member having a base material and an elastic layer provided on the outer circumference of the base material, wherein the elastic layer contains rubber and fillers dispersed in the rubber, the filler content in the elastic layer is 15 to 50 volume%, and when the fillers with large particle sizes are called filler A and those with small particle sizes are called filler B, the content of filler A is V A The content of filler A is 7-30% by volume, the average aspect ratio of filler A is 5.0-40.0, and the content of filler B is V B The filler B has a volume percentage of 7-30%, an average aspect ratio of 1.0-2.0, and an average orientation angle θ of the filler with an aspect ratio above a certain level. Ave The range is 0 to 45 degrees.

Description

[Technical Field]

[0001] This disclosure relates to an electrophotographic component used in a fixing device for an electrophotographic image forming apparatus, and to a fixing device and an electrophotographic image forming apparatus equipped with the electrophotographic component. [Background technology]

[0002] Electrophotographic components, such as fixing members used in the fixing devices of electrophotographic image forming devices like printers, copiers, and facsimile machines, come in film or roller forms. Fixing members are known to have, for example, a film or roller-shaped base material made of heat-resistant resin or metal, on which an elastic layer made of heat-resistant rubber or the like is formed as needed. To provide high thermal conductivity, the elastic layer is preferably made of rubber such as silicone rubber with a highly thermally conductive inorganic filler blended in as a filler.

[0003] In recent years, electrophotographic image forming apparatuses have been required to improve additional performance, such as further increasing print speed, improving image quality, energy efficiency, and compatibility with a wide variety of media. In fuser units, there is a need to increase the surface pressure at the fuser nip to increase the deformation of the toner and improve image quality. Furthermore, there is a need to further improve the thermal conductivity in the thickness direction of the elastic layer of the fuser component. However, increasing the amount of filler in the elastic layer to achieve higher thermal conductivity can lead to the elastic layer rupturing after prolonged use, resulting in durability issues. Therefore, there is a need for technology to improve the thermal conductivity of the elastic layer without excessively increasing the filler content.

[0004] Patent Document 1 discloses an electrophotographic member containing small-particle fillers arranged in the thickness direction of the elastic layer and large-particle fillers not arranged in the thickness direction of the elastic layer within the elastic layer. This makes it possible to improve thermal conductivity without increasing the amount of filler. Furthermore, Patent Document 2 discloses an electrophotographic member in which, in a binarized image of the cross-section of an elastic layer, a first filler with a major axis / minor axis ratio of less than 1.5 and a second filler with a major axis / minor axis ratio of 1.5 or more are included, and the second filler is oriented in the thickness direction of the elastic layer. This makes it possible to improve thermal conductivity without increasing the amount of filler. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2023-095891 [Patent Document 2] Japanese Patent Publication No. 2020-194156 [Overview of the project] [Problems that the invention aims to solve]

[0006] Patent Document 1 describes how arranging fillers in the thickness direction to form heat conduction paths can improve thermal conductivity compared to cases where the fillers are not arranged in the thickness direction. However, achieving higher thermal conductivity requires increasing the filler content beyond a certain level, posing a challenge in balancing thermal conductivity and durability.

[0007] Therefore, by oriented a filler with a high aspect ratio in the thickness direction of the elastic layer, as in the second filler of Patent Document 2, and forming a heat conduction path, high thermal conductivity can be obtained with a smaller filler content compared to when a filler with a low aspect ratio is used. However, the inventors have found that when using an electrophotographic component as a fixing member under conditions where the maximum surface pressure of the fixing nip portion of the fixing device is increased, the filler with a high aspect ratio is oriented in the thickness direction of the elastic layer. Even with these measures in place, we recognized that there were challenges in achieving both high thermal conductivity and durability.

[0008] This disclosure provides a highly durable electrophotographic component that exhibits high thermal conductivity and is resistant to rupture of the elastic layer even under prolonged use under conditions where the maximum surface pressure of the fixing nip portion is greater than that of conventional components. Furthermore, this disclosure provides a fixing apparatus and an electrophotographic image forming apparatus equipped with the above-mentioned electrophotographic component. [Means for solving the problem]

[0009] This disclosure relates to an electrophotographic member which is a rotating body having a substrate and an elastic layer provided on the outer circumference of the substrate, The elastic layer comprises rubber and fillers dispersed in the rubber. The filler content in the elastic layer is 15 to 50% by volume. Of these fillers, those with a particle size of 10 to 40 μm are designated as filler A. When filler B is defined as having a particle size of 3 μm or more and less than 10 μm, The content V of filler A in the elastic layer A However, it is 7-30% by volume. The average aspect ratio of filler A is 5.0 to 40.0. The content of filler B in the elastic layer V B However, it is 7-30% by volume. The average aspect ratio of filler B is 1.0 to 2.0. The plane in the thickness-circumferential direction of the elastic layer is defined as the first plane, and the planes obtained by rotating the first plane by 10° in the thickness-axial direction of the elastic layer are defined as the second to tenth planes. Cross-sectional images of the elastic layer with a size of 500 μm across the entire thickness of the elastic layer are acquired as the first to tenth cross-sectional images, such that they are parallel to the first to tenth planes and the center of the direction perpendicular to the thickness direction of the elastic layer coincides with the center of the electrophotographic member in the axial direction. The first to tenth cross-sectional images are each binarized to obtain the first to tenth binarized images. In the first to tenth binarized images, when the shape of the filler is approximated as an ellipse, The average orientation angle θ of the elliptical filler with respect to the thickness direction of the elastic layer, where the ratio of the major axis length to the minor axis length is 3.0 or greater. AveHowever, this relates to electrophotographic components with an angle of 0 to 45 degrees.

[0010] This disclosure is, Fixing member and A pressing member that faces the fixing member and forms a fixing nip portion that clamps and transports the recording material carrying the toner image between itself and the fixing member, A fixing device having, The present invention relates to a fixing device in which at least one of the fixing member and the pressing member is the electrophotographic member described above.

[0011] This disclosure relates to an electrophotographic image forming apparatus equipped with a fixing device, The present invention relates to an electrophotographic image forming apparatus in which the fixing device is the fixing device described above. [Effects of the Invention]

[0012] According to this disclosure, it is possible to provide a highly durable electrophotographic component that has high thermal conductivity and whose elastic layer is less likely to break even when used for a long period of time under conditions where the maximum surface pressure of the fixing nip portion is greater than that of conventional components. Furthermore, according to this disclosure, it is possible to provide a fixing apparatus and an electrophotographic image forming apparatus equipped with the above-mentioned electrophotographic component. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a schematic diagram of an electrophotographic image forming apparatus. [Figure 2] Figure 2 is a schematic diagram of the heating and fixing apparatus. [Figure 3] Figure 3 is a schematic diagram of the fixing film. [Figure 4] Figures 4A and 4B are an overhead view and a cross-sectional view of the corona charger. [Figure 5] Figure 5 is a schematic diagram of the 1st to 10th planes. [Figure 6] Figure 6 is a schematic diagram of the 1st to 10th sections. [Modes for carrying out the invention]

[0014] In this specification, descriptions of numerical ranges such as "XX or greater and YY or less" or "XX to YY" mean a numerical range that includes its endpoints, the lower and upper limits, unless otherwise specified. Furthermore, when numerical ranges are described in steps, the upper and lower limits of each numerical range can be any combination. In this disclosure, for example, a description such as "at least one selected from the group consisting of XX, YY, and ZZ" means any of XX, YY, ZZ, a combination of XX and YY, a combination of XX and ZZ, a combination of YY and ZZ, or a combination of XX, YY, and ZZ. Note that if XX is a group, multiple values ​​may be selected from XX, and the same applies to YY and ZZ.

[0015] The embodiments of this disclosure will be described in detail below. However, the technical scope of this disclosure is not limited to the following description.

[0016] As described above, when the maximum surface pressure of the fixing nip portion of the fixing device is increased, even if the filler with a high aspect ratio is oriented in the thickness direction of the elastic layer in the electrophotographic component, challenges arise in achieving both thermal conductivity and durability. The inventors believe the reason for this is as follows.

[0017] When stress is applied to the elastic layer, the deformation of the rubber is restricted by the filler, which can cause stress concentration near the filler and lead to the formation of microcracks. Since intense stress concentration also occurs near these microcracks, if many microcracks occur in the elastic layer, they influence each other and propagate into larger cracks. In the anchoring nip, shear stress is applied to the elastic layer, so it is thought that the above phenomenon occurs when the elastic layer ruptures due to long-term use of the anchoring member.

[0018] In this case, the higher the aspect ratio and the larger the particle size of the filler, the more intense the stress concentration becomes near the tip of the filler. Also, the closer the distance between adjacent fillers, the more intense the stress concentration becomes. Therefore, it is presumed that if fillers with a high aspect ratio are oriented in the thickness direction of the elastic layer, the stress distribution within the elastic layer is likely to become non-uniform.

[0019] Under conditions where the maximum surface pressure at the anchoring nip is high, if the stress distribution in the elastic layer is non-uniform, localized stress values ​​become extremely high, leading to the generation of numerous microcracks in the elastic layer. Therefore, it is thought that the elastic layer may rupture with long-term use, resulting in durability issues. The inventors of this invention have conducted thorough research and have found that the following configuration can achieve both thermal conductivity and durability.

[0020] This disclosure relates to an electrophotographic member which is a rotating body having a substrate and an elastic layer provided on the outer circumference of the substrate, The elastic layer comprises rubber and fillers dispersed in the rubber. The filler content in the elastic layer is 15 to 50% by volume. Of these fillers, those with a particle size of 10 to 40 μm are designated as filler A. When filler B is defined as having a particle size of 3 μm or more and less than 10 μm, The content V of filler A in the elastic layer A However, it is 7-30% by volume. The average aspect ratio of filler A is 5.0 to 40.0. The content of filler B in the elastic layer V B However, it is 7-30% by volume. The average aspect ratio of filler B is 1.0 to 2.0. The plane in the thickness-circumferential direction of the elastic layer is defined as the first plane, and the planes obtained by rotating the first plane by 10° in the thickness-axial direction of the elastic layer are defined as the second to tenth planes. A cross-sectional image with a size of 500 μm across the entire thickness of the elastic layer is shown, along with the first to tenth planes, respectively. First to tenth cross-sectional images are acquired such that they are parallel and the center of the direction perpendicular to the thickness direction of the elastic layer coincides with the center of the electrophotographic member in the axial direction. The first to tenth cross-sectional images are each binarized to obtain the first to tenth binarized images. In the first to tenth binarized images, when the shape of the filler is approximated as an ellipse, The average orientation angle θ of the elastic layer of the filler approximated by an ellipse, where the ratio of the major axis length to the minor axis length is 3.0 or more, with respect to the thickness direction Ave is from 0 to 45°, and relates to an electrophotographic member.

[0021] The electrophotographic member of the present disclosure includes filler A and filler B. Hereinafter, a mechanism by which the thermal conductivity and durability of the elastic layer are improved will be described in terms of the combination of filler A having a large particle size and a large aspect ratio and filler B having a small particle size and a small aspect ratio, and the mode of existence of the fillers in the elastic layer.

[0022] First, from the viewpoint of heat conduction, it is necessary to include fillers with a high aspect ratio and have a distribution of filler particle sizes with large and small sizes. When using fillers with a high aspect ratio, by efficiently transferring heat in the orientation direction of the fillers, it is possible to increase the thermal conductivity in the thickness direction without excessively increasing the total filler amount. Further, when there is a wide range of large and small sizes in the filler particle size distribution, a heat conduction path is formed by the small-diameter fillers filling the gaps between the large-diameter fillers, resulting in excellent thermal conductivity in the elastic layer thickness direction. Therefore, by setting the filler content, V A and V B to be not less than the above lower limit, setting the aspect ratio of filler A to be 5.0 or more, and setting the average value θ Ave of the orientation angle within the above range, the thermal conductivity becomes good.

[0023] Next, from the viewpoint of durability, in order to suppress the situation where when a large stress is applied to the elastic layer, a large stress is applied to the rubber matrix and the rubber breaks, it is necessary to have a distribution of filler particle sizes with large and small sizes and reduce the combination of adjacent fillers where stress is likely to concentrate. When there is a wide range of large and small sizes in the filler particle size distribution, it is likely to become a uniform dispersion state where small-diameter particles enter the gaps between large-diameter particles. Even when a large strain is applied to the elastic layer, the stress is dispersed throughout the matrix, suppressing the generation of cracks, and thus excellent in durability.

[0024] Furthermore, when large stresses are applied where fillers are close together, microcracks occur. Once a microcrack occurs, stress concentrates at the microcrack, causing it to connect with other adjacent microcracks and propagate, ultimately leading to fracture of the elastic layer. Therefore, since the occurrence of numerous microcracks in the elastic layer reduces durability, selecting a combination of fillers that can reduce the frequency of microcrack occurrence is necessary to improve durability.

[0025] Regarding stress concentration that causes microcracks, the larger the grain size of the filler, the more the deformation of the matrix is ​​constrained, resulting in greater stress concentration. Furthermore, the smaller the curvature of the tip of adjacent fillers, the greater the stress concentration. Therefore, the combination of adjacent fillers that results in the greatest stress concentration is two large-diameter, high-aspect-ratio fillers, followed by a large-diameter, high-aspect-ratio filler and a small-diameter, high-aspect-ratio filler.

[0026] The inventors have found that even when using large-diameter, high-aspect-ratio fillers, microcracks can be suppressed by combining them with small-diameter, low-aspect-ratio fillers. Since large-diameter, high-aspect-ratio fillers are few in number in the elastic layer, it is thought that the frequency of microcrack occurrence can be significantly reduced by combining them with small-diameter fillers with a small aspect ratio. Therefore, from the viewpoint of durability, the filler content, V A and V B It is important to keep the above upper limit below the required value and to control the aspect ratio of filler A and filler B.

[0027] In summary, by combining large-diameter, high-aspect-ratio fillers with small-diameter, low-aspect-ratio fillers, controlling their content, and further controlling the orientation of the high-aspect-ratio fillers, electrophotographic components with thermal conductivity and durability can be obtained. The requirements are explained below.

[0028] The elastic layer contains fillers. Fillers can be added, for example, to control thermal conductivity, heat resistance, and elastic modulus. The filler content in the elastic layer is 15 to 50 volume percent. A filler content of 15 volume percent or more allows for high thermal conductivity of the elastic layer and good adhesion. A filler content of 50 volume percent or less allows for sufficient spacing between fillers, which suppresses the generation of microcracks in the elastic layer caused by stress concentration between close fillers when a large stress is applied to the elastic layer, resulting in excellent durability. The filler content in the elastic layer is preferably 18 to 42 volume%, more preferably 20 to 40 volume%, and even more preferably 25 to 35 volume%.

[0029] Of the above fillers, those with a particle size of 10 to 40 μm are designated as filler A, and those with a particle size of 3 μm or more and less than 10 μm are designated as filler B. At this time, the content V of filler A in the elastic layer A The volume is 7-30%, and the average aspect ratio of filler A is 5.0-40.0. Also, the content of filler B in the elastic layer is V B The volume percentage is 7-30%, and the average aspect ratio of filler B is 1.0-2.0.

[0030] V A The presence of 7% or more by volume results in excellent thermal conductivity, V A The fact that the percentage of filler is 30% or less by volume results in superior durability. Furthermore, the fact that the average aspect ratio of filler A is 5.0 or higher allows for improved thermal conductivity in the thickness direction without excessively increasing the total amount of filler. The fact that the average aspect ratio of filler A is 40.0 or less results in superior durability. V B The presence of 7% or more by volume results in excellent thermal conductivity, V B The fact that the percentage of filler B is 30% or less by volume contributes to its superior durability. Furthermore, the fact that the average aspect ratio of filler B is 2.0 or less contributes to its superior durability.

[0031] From the perspective of further improving thermal conductivity and durability, V A The amount is preferably 10-20% by volume, and more preferably 13-20% by volume. The average aspect ratio of filler A is preferably 10.0-40.0, more preferably 10.0-30.0, and even more preferably 13.0-20.0. V B The amount of filler B is preferably 10-20% by volume, and more preferably 13-20% by volume. The average aspect ratio of filler B is preferably 1.0-1.5, more preferably 1.0-1.2, even more preferably 1.0-1.1, and even more preferably 1.00-1.04.

[0032] From the viewpoint of further improving thermal conductivity and durability, filler A preferably includes a flat plate-shaped filler, and more preferably a flat plate-shaped filler. Filler B preferably includes a spherical or substantially spherical filler with an aspect ratio of 1.0 to 2.0.

[0033] 100 fillers were observed using a field emission scanning electron microscope (FE-SEM), and the volume V of filler A was determined. f and the volume V of filler B f The sum of the total filler volume V f V is the value obtained by dividing by the sum V. A+B Let's assume that. V A+B This indicates the ratio of the total amount of filler A and filler B in the elastic layer. V A+B For example, it is 0.80 or higher, preferably 0.90 or higher, more preferably 0.95 or higher, and even more preferably 0.97 or higher. A+B The upper limit is particularly Unrestricted. V A+B For example, this is 0.80 to 1.00, preferably 0.90 to 1.00, more preferably 0.95 to 1.00, and even more preferably 0.97 to 0.99.

[0034] V A / V BThe value is, for example, 0.4 to 3.0, preferably 0.5 to 2.0, more preferably 0.6 to 1.5, and even more preferably 0.8 to 1.3. Within this range, thermal conductivity and durability are more easily achieved.

[0035] Furthermore, the plane in the thickness-circumferential direction of the elastic layer is defined as the first plane, and the planes obtained by rotating the first plane 10° in the thickness-axial direction of the elastic layer are defined as the second to tenth planes. The circumferential direction is the circumferential direction of the rotating body, and the axial direction is the rotation axis direction of the rotating body. Cross-sectional images of the elastic layer with a size of 500 μm across the entire thickness of the elastic layer are acquired as the first to tenth cross-sectional images, such that they are parallel to the first to tenth planes and the center of the direction perpendicular to the thickness direction of the elastic layer coincides with the center of the electrophotographic member in the axial direction. The acquired first to tenth cross-sectional images are each binarized to obtain the first to tenth binarized images, and the shape of the filler is approximated as an ellipse in the first to tenth binarized images.

[0036] The average orientation angle θ of the elliptical filler with respect to the thickness direction of the elastic layer, where the ratio of the major axis length to the minor axis length is 3.0 or greater. Ave However, the angle must be between 0 and 45 degrees. Ave Because the range is within this range, the thermal conductivity in the thickness direction can be increased without excessively increasing the total amount of filler in the elastic layer. As a result, an electrophotographic component with improved thermal conductivity in the thickness direction can be obtained without reducing the durability of the elastic layer.

[0037] θ Ave θ is preferably 0 to 40°, more preferably 0 to 30°, and even more preferably 0 to 25°. The lower limit is preferably as small as possible and is not particularly limited, but θ Ave The angles may preferably be 10-40°, 12-30°, or 15-25°. Average orientation angle θ of the filler Ave This is preferably controlled, for example, by an electric field application process to the elastic layer, which will be described later.

[0038] <Electrophotographic components> An electrophotographic member in at least one aspect of this disclosure is, for example, a fixing member. Alternatively, the electrophotographic member may be a rotating body. The electrophotographic member may be roller-shaped or belt-shaped. For example, the electrophotographic member may be a fixing belt. Alternatively, the electrophotographic member may be an endless electrophotographic belt. The electrophotographic member comprises a substrate and an elastic layer provided on the outer circumference of the substrate. The electrophotographic member may have a surface layer on the outer surface of the elastic layer. The substrate may be, for example, a base layer. Other layers may be provided between the substrate, the elastic layer, and the surface layer, as well as on the inner circumferential surface of the substrate and the outer circumferential surface of the surface layer, as needed.

[0039] The fixing member 41 is, for example, a fixing film 41, as shown in Figures 2 and 3. The fixing member 41 has a base material 41b and an elastic layer 41c. The fixing member 41 may have a surface layer 41a on the outer peripheral surface of the elastic layer 41c. The surface layer 41a can be a release layer that has release properties for toner, for example. The surface layer 41a can form the outer surface of the electrophotographic member. The surface layer 41a may be bonded to the surface of the elastic layer 41c with an adhesive layer (not shown). In addition, the inner peripheral surface of the base material 41b may have an inner sliding layer (not shown).

[0040] The following provides a detailed explanation of each layer. <Base material> The material of the base material 41b is not particularly limited and can be any known electrophotographic material. For example, metals such as aluminum, iron, stainless steel (SUS), and nickel. Alloys and heat-resistant resins such as polyimide are used. Stainless steel is preferred. The thickness of the base material 41b is not particularly limited, but from the viewpoint of strength, flexibility and heat capacity, it is preferably 20 μm to 100 μm, and more preferably 20 μm to 50 μm.

[0041] The outer surface of the substrate 41b may be subjected to a surface treatment to provide adhesion to the elastic layer 41c. The surface treatment can be one or more types of physical treatments such as blasting, lapping, and polishing, or chemical treatments such as oxidation, coupling agent treatment, and primer treatment.

[0042] When an elastic layer 41c containing silicone rubber is provided on the surface of the substrate 41b, it is preferable to apply a primer treatment to the surface of the substrate 41b in order to improve the adhesion between the substrate 41b and the elastic layer 41c. Examples of primers used for the primer treatment include paints in which a silane coupling agent, a silicone polymer, methyl siloxane hydrogenation, an alkoxysilane, a reaction-accelerating catalyst, and a coloring agent such as red iron oxide are appropriately blended and dispersed in an organic solvent.

[0043] The primer can be appropriately selected depending on the material of the substrate 41b, the type of elastic layer 41c, or the form of the crosslinking reaction. In particular, when the elastic layer 41c contains many unsaturated aliphatic groups, a primer containing hydrosilyl groups is preferably used to impart adhesion through reaction with the unsaturated aliphatic groups.

[0044] Other primers that may be used include those containing alkoxy groups. Commercially available primers can be used. The priming treatment also includes the step of applying the primer to the outer surface of the substrate 41b (the surface that adheres to the elastic layer 41c) and drying or firing it.

[0045] <Internal sliding layer> An internal sliding layer may be provided on the inner circumferential surface of the base material 41b. A resin that combines high durability and high heat resistance, such as polyimide resin, is suitable for the internal sliding layer. Since the internal sliding layer is rubbed and gradually wears down, it is preferable to provide a thickness that is sufficient to function as a sliding layer throughout its lifespan. On the other hand, a thickness that does not obstruct heat supply from the heater is also preferable. For this reason, a thickness of 5 to 20 μm is preferred, and 10 to 15 μm is more preferred. The internal sliding layer may be formed using known coating methods or the like.

[0046] <Elastic layer> The elastic layer 41c is a layer that provides flexibility to the electrophotographic component in order to ensure a fixing nip in the fixing device. Furthermore, when the electrophotographic component is used as a heating component that comes into contact with toner on paper, the elastic layer 41c also functions as a layer that provides flexibility to the surface of the heating component so that it can conform to the irregularities of the paper.

[0047] The elastic layer 41c comprises rubber and fillers dispersed in the rubber. In the elastic layer, the rubber is, for example, a matrix. More specifically, the elastic layer 41c comprises rubber and fillers dispersed in the rubber, and is composed of a cured product obtained by curing a mixture containing at least rubber raw materials (base polymer, crosslinking agent, etc.) and fillers.

[0048] The modulus of elasticity of the elastic layer 41c is preferably 0.60 to 2.00 MPa, more preferably 0.65 to 1.20 MPa, and even more preferably 0.70 to 0.90 MPa. A modulus of elasticity of 0.60 MPa or higher provides superior durability, while a modulus of elasticity of 2.00 MPa or lower provides flexibility. The elastic modulus of the elastic layer 41c can be controlled by the volume fraction of the filler relative to the elastic layer. Furthermore, the elastic modulus of the elastic layer 41c can also be changed by the amount of crosslinking agent contained in the rubber raw material.

[0049] Furthermore, the thickness of the elastic layer can be appropriately designed considering the surface hardness of the electrophotographic component and the width of the nip portion to be formed. The thickness of the elastic layer 41c is preferably 150 to 500 μm, more preferably 200 to 400 μm, and even more preferably 200 to 300 μm.

[0050] From the viewpoint of good adhesion, the thermal conductivity in the thickness direction of the elastic layer is preferably 1.25 W / (m·K) or higher. More preferably, the thermal conductivity is 1.40 W / (m·K) or higher. The higher the thermal conductivity in the thickness direction of the elastic layer, the better, and there is no particular upper limit, but for example, it is 1.25 to 2.50 W / (m·K), 1.40 to 2.00 W / (m·K), or 1.50 to 2.00 W / (m·K).

[0051] The elastic layer 41c preferably contains silicone rubber with excellent heat resistance. That is, the rubber in the elastic layer is preferably silicone rubber. Furthermore, an addition-curing type liquid silicone rubber is preferably used as the raw material for the silicone rubber. The elastic layer 41c can be formed, for example, by coating the outer surface of the substrate 41b with an addition-curing type liquid silicone rubber mixture and then heat-curing it. The coating method is not particularly limited, and any known method may be used. Since silicone rubber mixtures are mostly liquid, fillers disperse easily, and the elasticity of the resulting elastic layer can be easily adjusted by adjusting the degree of crosslinking according to the type and amount of filler added, which is preferable.

[0052] The matrix plays a role in providing elasticity to the elastic layer. From the viewpoint of enabling the elastic layer to perform the functions described above, the matrix preferably contains silicone rubber. Silicone rubber is preferable because it has high heat resistance that allows it to maintain flexibility even in environments where the non-paper-feeding area reaches high temperatures of about 240°C. As the silicone rubber, for example, a cured product of addition-curing type liquid silicone rubber described later can be used.

[0053] Liquid silicone rubber mixtures typically contain the following components (a) to (d): Component (a): Organopolysiloxane having an unsaturated aliphatic group; Component (b): Organopolysiloxane having active hydrogen bonded to silicon; Component (c): catalyst; Ingredient (d): Filler The following describes each component.

[0054] Component (a): Organopolysiloxane having an unsaturated aliphatic group An organopolysiloxane having an unsaturated aliphatic group is an organopolysiloxane having an unsaturated aliphatic group such as a vinyl group, and includes, for example, at least one selected from the group consisting of compounds represented by formula (1) and compounds represented by formula (2) below. The organopolysiloxane having an unsaturated aliphatic group is preferably linear. [ka]

[0055] In formula (1), m 1 n represents an integer greater than or equal to 0 (preferably between 500 and 1100), and n 1 R represents an integer of 3 or greater (preferably 10 to 40). Also, in structural formula (1), R 1 Each of these independently represents a monovalent unsubstituted or substituted hydrocarbon group that does not contain an unsaturated aliphatic group, provided that R 1 At least one of them represents a methyl group, R 2 Each of these independently represents an unsaturated aliphatic group. [ka]

[0056] In formula (2), n 2 R represents a positive integer (preferably between 500 and 1100), and 3 Each of these independently represents a monovalent unsubstituted or substituted hydrocarbon group that does not contain an unsaturated aliphatic group, provided that R 3 At least one of them represents a methyl group, R 4 Each of these independently represents an unsaturated aliphatic group.

[0057] In equations (1) and (2), R 1 and R 3 Examples of monovalent unsubstituted or substituted hydrocarbon groups that do not contain unsaturated aliphatic groups that can be represented by include the following groups: • Unsubstituted hydrocarbon groups Alkyl groups (e.g., methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group). Aryl group (for example, phenyl group). Substituting hydrocarbon groups Substitutive alkyl groups (e.g., chloromethyl group, 3-chloropropyl group, 3,3,3-trifluoropropyl group, 3-cyanopropyl group, 3-methoxypropyl group).

[0058] The organopolysiloxanes represented by formulas (1) and (2) have at least one methyl group directly bonded to the silicon atom forming the chain structure. However, because they are easy to synthesize and handle, R 1 and R 3 Preferably, more than 50% of each is a methyl group, and all R 1 and R 3 It is more preferable that the group is a methyl group.

[0059] Also, in equations (1) and (2), R 2 and R 4 Examples of unsaturated aliphatic groups that can be represented include the following groups. Specifically, examples of unsaturated aliphatic groups include vinyl groups, allyl groups, 3-butenyl groups, 4-pentenyl groups, and 5-hexenyl groups. Among these groups, R is chosen because it is easy and inexpensive to synthesize and handle, and crosslinking reactions can be easily carried out with it. 2 and R 4 Preferably, all of these are vinyl groups.

[0060] As for component (a), from the viewpoint of moldability, the viscosity is 1000 mm 2 / s or more 50000mm 2 Preferably, it should be less than / s, and 1000mm 2 / s or more 20000mm 2 It is more preferable that it be less than or equal to / s, and 3000mm 2 / s or more 8000mm 2 It is even more preferable that the interval be less than or equal to / s. 1000mm 2 If the value is above / s, it becomes easier to adjust the hardness required for the elastic layer, 50,000 mm 2 A viscosity of less than / s makes coating easier. Viscosity (kinematic viscosity) can be measured using a capillary viscometer, rotational viscometer, etc., in accordance with JIS Z 8803:2011.

[0061] The amount of component (a) is preferably 50% by volume or more from the viewpoint of durability and 85% by volume or less from the viewpoint of heat transfer, based on the liquid silicone rubber mixture used to form the elastic layer, and more preferably 60% by volume or more from the viewpoint of durability and 80% by volume or less from the viewpoint of heat transfer.

[0062] Component (b): Organopolysiloxane having active hydrogen bonded to silicon Organopolysiloxanes, which have active hydrogen bonded to silicon, react with the unsaturated aliphatic group of component (a) through the action of a catalyst and function as a crosslinking agent to form cured silicone rubber. Any organopolysiloxane having a Si-H bond can be used as component (b). In particular, from the viewpoint of reactivity with the unsaturated aliphatic group of component (a), those having an average of 3 or more hydrogen atoms bonded to the silicon atom in one molecule are preferably used.

[0063] Specific examples of component (b) include, for example, the linear organopolysiloxane shown in formula (3) below and the cyclic organopolysiloxane shown in formula (4) below. [ka]

[0064] In formula (3), m 2 n represents an integer greater than or equal to 0 (preferably 10 to 30), and n 3R represents an integer of 3 or greater (preferably 5 to 20), 5 Each of these independently represents a monovalent unsubstituted or substituted hydrocarbon group that does not contain an unsaturated aliphatic group. [ka]

[0065] In formula (4), m 3 n represents an integer greater than or equal to 0 (preferably 10 to 30), and n 4 R represents an integer of 3 or greater (preferably 5 to 20), 6 Each of these independently represents a monovalent unsubstituted or substituted hydrocarbon group that does not contain an unsaturated aliphatic group.

[0066] R in equations (3) and (4) 5 and R 6 Examples of monovalent unsubstituted or substituted hydrocarbon groups that do not contain unsaturated aliphatic groups that can be represented include R in formula (1) above. 1 Similar groups can be cited. Among these, R is chosen because it is easy to synthesize and handle, and excellent heat resistance can be easily obtained. 5 and R 6 Preferably, more than 50% of each is a methyl group, and all R 5 and R 6 It is more preferable that the group is a methyl group.

[0067] Component (c): Catalyst Examples of catalysts used in the formation of silicone rubber include hydrides to accelerate the curing reaction. Hydrosilylation catalysts can be used. For example, known substances such as platinum compounds and rhodium compounds can be used as hydrosilylation catalysts. The amount of catalyst can be set as appropriate and is not particularly limited.

[0068] Ingredient (d): Filler As mentioned above, the elastic layer contains filler. Filler materials are selected considering their own thermal conductivity, specific heat capacity, density, particle size, relative permittivity, etc. Examples of fillers used to improve the heat transfer properties of inorganic materials, especially metals and metallic compounds, include: silicon carbide, silicon nitride, boron nitride, aluminum nitride, alumina, zinc oxide, magnesium oxide, silica, copper, aluminum, silver, iron, nickel, metallic silicon, and carbon fiber. Furthermore, from the viewpoint of the thermal conductivity, electrical resistance, and relative permittivity of the filler itself, it is more preferable that fillers A and B are at least one filler selected from the group consisting of alumina, zinc oxide, metallic silicon, silicon carbide, boron nitride, and magnesium oxide.

[0069] Filler A preferably contains boron nitride. In particular, filler A preferably contains flat boron nitride. Filler A preferably has a 10% particle size (D10) of 10% of its volume distribution (D10) of 10.0 to 40.0 μm, and more preferably of 10.0 to 17.0 μm. Filler A preferably has a 50% particle size (D50) based on volume distribution of 10.0 to 40.0 μm, and more preferably 11.0 to 20.0 μm. Filler A preferably has a 90% particle size (D90) based on volume distribution of 10.0 to 40.0 μm, and more preferably 16.0 to 24.0 μm.

[0070] Filler B may include, for example, alumina particles. Filler B preferably has a 10% particle size (D10) based on volume distribution of 3.0 μm or more and less than 10.0 μm, and more preferably 3.0 to 5.0 μm. Filler B preferably has a 50% particle size (D50) based on volume distribution of 3.0 μm or more and less than 10.0 μm, and more preferably 3.0 to 6.0 μm. Filler B preferably has a 90% particle size (D90) based on volume distribution of 3.0 μm or more and less than 10.0 μm, and more preferably 5.0 to 9.9 μm.

[0071] Below, as one embodiment, a corona charger 2 and the process of applying an electric field to an elastic layer using it will be described. There are two types of corona charging methods: the scorotron method, which has a grid electrode between the corona wire and the object to be charged, and the corotron method, which does not have a grid electrode. However, from the viewpoint of controllability of the surface potential of the object to be charged, the scorotron method is preferred. As shown in Figures 4A and 4B, the corona charger 2 comprises a front block 201, a back block 202, and shields 203 and 204. A discharge wire 205 is stretched between the front block 201 and the back block 202, and when a charging bias is applied by a high-voltage power supply, it discharges and charges the surface of the uncured elastic layer 41c on the substrate, which is the object to be charged.

[0072] Similar to the configuration of a typical corona charger, a high voltage is applied to the discharge wire 205, which acts as the discharge element. The ion flow obtained by the discharge to the shields 203 and 204 is then controlled by applying a high voltage to the grid 206 to control the surface of the elastic layer 41c to a desired charging potential. At this time, since the base material 41b or the core 1 holding the base material 41b is grounded (not shown), it is possible to generate a desired electric field on the elastic layer 41c by controlling the surface potential of the surface of the elastic layer 41c.

[0073] To describe in detail the manufacturing method of the fixing member of the above embodiment, first, an elastic layer having silicone rubber containing filler is formed on the base material. Next, as shown in Figure 4A, the corona charger 2 is formed into a fixing part The materials 41 are positioned close together and facing each other along the width direction of the elastic layer 41c before it hardens. Then, a voltage is applied to the grid 206 of the corona charger 2, and the fixing member 41 is rotated for 160 seconds at, for example, 141 rpm while the grid is discharged, thereby charging the surface of the elastic layer. The distance between the surface of the elastic layer and the grid 206 can be 1 mm to 10 mm. By charging the surface of the elastic layer 41c in this way, an electric field is generated within the elastic layer, orienting the thermally conductive filler. After that, the elastic layer is hardened by heating or the like to fix the orientation of the filler.

[0074] The voltage applied to the grid 206 is preferably in the range of 0.1kV to 3kV (0.2 to 6kV in Vp-p in the case of AC application) in absolute value, from the viewpoint of generating an effective electrostatic interaction with the filler. When using an electric field to form the orientation of the filler in the thickness direction of the elastic layer, it is important to generate an electric field in the thickness direction of the elastic layer 41c. If the sign of the applied voltage is the same as the sign of the voltage applied to the wire, the effect obtained will be the same whether the sign is negative or positive, although the direction of the electric field will be reversed.

[0075] Furthermore, when AC charging is applied to suppress surface flow, as described later, it is desirable to match the phase of the waveforms of the wire and grid. Depending on the type and amount of filler, filler orientation may be difficult to form, in which case it is desirable to increase the voltage applied to grid 206. This is presumed to be related to the dielectric constants of the silicone rubber component and the thermally conductive filler. When the difference in dielectric constant between the silicone rubber and the filler is large, or when the amount is small, it is possible to form filler orientation with a relatively small applied voltage.

[0076] On the other hand, if the voltage applied to grid 206 is too high, the electrostatic repulsive force due to the surface charge of the elastic layer becomes large, causing surface flow and potentially reducing the surface properties of the elastic layer 41c. Therefore, a more preferable range for the voltage applied to grid 206 is 0.1kV to 1.5kV in absolute value (0.2 to 3kV in Vp-p when AC is applied). This surface flow can be mitigated by AC charging.

[0077] As a configuration for controlling the potential in the longitudinal direction of the elastic layer surface, for example, the configuration shown in Figure 4A can be used. While a voltage is applied to the grid 206, the entire elastic layer 41c can be charged by rotating the fixing member 41 around its central axis. The rotation speed of the fixing member is preferably 10 rpm to 500 rpm, and the processing time is preferably 20 seconds or more from the viewpoint of stably forming the orientation of the filler. Thus, by controlling the voltage value applied to the grid and the time for applying the electric field, the average orientation angle θ of the filler can be controlled. Ave It can be controlled.

[0078] As the discharge wire 205, stainless steel, nickel, molybdenum, tungsten, etc. may be used, but it is preferable to use tungsten, which has very high stability among metals. The discharge wire stretched inside the shield may have a circular cross-sectional shape or a sawtooth shape.

[0079] Furthermore, the diameter of the discharge wire 205 is preferably 40 μm to 100 μm. By keeping the diameter of the discharge wire within this range, it is possible to prevent the discharge wire from being cut by ions during discharge, and it is not necessary to make the voltage required to generate corona discharge excessively high. The voltage applied to the discharge wire 205 can be either a DC voltage or an AC voltage. In the case of an AC voltage, it is preferable to use a frequency of about 0.01 Hz to 1000 Hz. The voltage can be generated by outputting a square wave, sine wave, or other waveform using an arbitrary waveform generator.

[0080] <Surface layer> The electrophotographic member may have a surface layer 41a on the outer surface of the elastic layer 41c. 1a can be a fluororesin material with a thickness of 100 μm or less, preferably 10 to 70 μm. Examples of fluororesin layers include PTFE, FEP, and PFA, but PFA is preferred from the viewpoint of mold release properties and rigidity. PFA is a copolymer of perfluoroalkyl vinyl ether (PAVE) and tetrafluoroethylene (TFE).

[0081] One method for forming the surface layer 41a containing PFA is to coat the surface of the elastic layer 41c with a dispersion (water-based dispersion paint) or powder paint mainly composed of PFA, and then heat it above its melting point to form a film. Alternatively, one method is to coat the surface of the elastic layer 41c with a PFA tube manufactured separately by extrusion molding. The surface layer 41a is, for example, a PFA tube.

[0082] Commercially available PFAs can be used. Specifically, examples include AP-230 (product name, manufactured by Daikin Industries), AP-231SH (product name, manufactured by Daikin Industries), which is a PFA with fully fluorinated terminal groups, and 451HP-J (product name, manufactured by Mitsui Chemours Fluoroproducts), which has a small spherulite size.

[0083] The inner surface of the surface layer 41a can be pre-treated with sodium treatment, excimer laser treatment, ammonia treatment, or plasma etching to improve adhesion. In this embodiment, a 20 μm thick PFA tube obtained by extrusion molding was used.

[0084] <Adhesive layer> The surface layer 41a may be bonded to the surface of the elastic layer 41c with an adhesive layer (not shown). The presence of an adhesive layer facilitates bonding between the elastic layer and the surface layer. The material of the adhesive layer is not particularly limited, and known materials can be used. For example, the adhesive layer preferably contains a cured product of an adhesive. The adhesive may be a solution-type adhesive or a hot-melt-type adhesive.

[0085] The adhesive is not particularly limited, and any known adhesive can be used, but it is preferable to use a silicone rubber adhesive. The thickness of the adhesive layer is not particularly limited, but is preferably 1 to 20 μm, and more preferably 3 to 10 μm.

[0086] <Electrophotographic image forming apparatus> Figure 1 is a cross-sectional view of a color electrophotographic printer, which is an example of the electrophotographic image forming apparatus (hereinafter also referred to as the "image forming apparatus") of this embodiment, and is a cross-sectional view along the direction of transport of the recording material. In this embodiment, the color electrophotographic printer is simply referred to as the "printer".

[0087] The printer 1 shown in Figure 1 is equipped with image forming units 10 for each color: Y (yellow), M (magenta), C (cyan), and Bk (black). The photosensitive drum (photoreceptor) 11 is pre-charged by a charger 12. Then, the photosensitive drum 11 is exposed by a laser scanner 13 to form an electrostatic latent image. The electrostatic latent image is converted into a toner image by a developer 14. The toner image on the photosensitive drum 11 is sequentially transferred by a primary transfer blade 17 to an image carrier, such as an intermediate transfer belt 31. After transfer, any toner remaining on the photosensitive drum 11 is removed by a cleaner 15. As a result, the surface of the photosensitive drum 11 becomes clean and ready for the next image formation.

[0088] Meanwhile, the recording material P is fed one sheet at a time from the paper feed cassette 20 or the multi-feed tray 25 in the direction of arrow 3 and fed to the registration roller pair 23. The registration roller pair 23 first receives the recording material P and straightens it if it is skewed. Then, the registration roller pair 23 synchronizes with the toner image on the intermediate transfer belt 31 and feeds the recording material P between the intermediate transfer belt 31 and the secondary transfer roller 35. The toner image is transferred to the recording material P by a transfer body, such as a secondary transfer roller 35. Subsequently, the toner image on the recording material P is fixed to the recording material P by heating and pressurizing the recording material P with a fixing device 40.

[0089] The electrophotographic image forming apparatus includes a fixing device 40. Next, the fixing device in the electrophotographic image forming apparatus will be described. The fixing device comprises a fixing member and a pressing member positioned opposite the fixing member. Figure 2 is a schematic diagram of the fixing device 40, and is an example of a film heating type heating device (tensionless type). In this embodiment, such a heating device was used, but it can also be implemented with a roller pair type or a film type heating device.

[0090] 43 is a ceramic heater (hereinafter referred to as "heater") serving as a heating element. Heater 43 basically consists of a long, narrow ceramic substrate with its length perpendicular to the drawing, and an electrically conductive heat-generating resistor layer provided on the surface of this substrate. Heater 43 is a low-heat-capacity heater that heats up with a steep rise characteristic throughout when current is applied to the heat-generating resistor layer. Furthermore, it is configured to switch the energized area according to the length width size of the recording material.

[0091] An electrophotographic member according to at least one aspect of this disclosure can be used, for example, as a fixing member. The fixing film 41 is a cylindrical (endless) heat-resistant fixing member that acts as a heating member for transferring heat, and is loosely fitted onto a support member (heater holder) including the heater 43. The structure of the fixing film 41 is as shown in Figure 3, and is a fixing film having a three-layer composite structure including at least a surface layer 41a, an elastic layer 41c, and a base material 41b.

[0092] The pressure roller 44 is a heat-resistant elastic pressure roller used as a pressure member, and has a core metal and an elastic layer made of heat-resistant rubber such as silicone rubber or fluororubber, or a silicone rubber foam. Both ends of the core metal are arranged to be rotatably supported by bearings. At least one aspect of the electrophotographic member according to this disclosure can also be used, for example, as a pressure member. That is, it is preferable that at least one of the fixing member and the pressure member is the electrophotographic member described above. For example, the pressure member may have the same configuration as the fixing film 41, and the pressure member may have a three-layer composite structure including a surface layer 41a, an elastic layer 41c, and a base material 41b.

[0093] The fixing film 41 and heater 43 are positioned above the pressure roller 44, parallel to the pressure roller 44, and pressed together with a pressing member (not shown). In this way, the lower surface of the heater 43 and the upper surface of the pressure roller 44 are pressed together against the elasticity of the elastic layer via the fixing film 41, thereby forming a fixing nip portion N of a predetermined width which serves as a heating portion.

[0094] The pressure roller 44 is driven to rotate at a predetermined peripheral speed in the counterclockwise direction indicated by the arrow by a driving means (not shown). Due to the rotational drive of the pressure roller 44, a rotational force is applied to the cylindrical fixing film 41 by the pressure friction force at the fixing nip portion N between the pressure roller 44 and the fixing film 41. The fixing film 41 then slides in close contact with the downward surface of the heater 43 and enters a state of driven rotation in the clockwise direction indicated by the arrow. The support member (heater holder) 46 also serves as a rotation guide member for the cylindrical fixing film 41.

[0095] The pressure roller 44 is driven to rotate, causing the cylindrical fixing film 41 to rotate along with it. The heater 43 is also energized, causing it to rapidly heat up to a predetermined temperature and reach a temperature-controlled state. In this state, a recording material P carrying an unfixed toner image T is introduced between the fixing film 41 and the pressure roller 44 in the fixing nip section N. Then, in the fixing nip section N, the toner image-carrying side of the recording material P comes into close contact with the outer surface of the fixing film 41, and the recording material P is clamped and transported together with the fixing film 41 in the fixing nip section N. During this process, the recording material P is heated by the heat of the fixing film 41 heated by the heater 43, and the unfixed toner image T on the recording material P is heated and pressurized onto the recording material P and melted and fixed. The recording material P that has passed through the fixing nip section N is separated from the surface of the fixing film 41 by curvature and discharged and conveyed.

[0096] The maximum surface pressure in the direction of transport of the recording material at the fixing nip section N is preferably 0.25 to 0.40 MPa, and more preferably 0.35 to 0.40 MPa. By increasing the surface pressure at the fixing nip section, the amount of toner deformation can be increased, thereby improving image quality.

[0097] The pressure applied to the fixing nip section N is measured using a tactile sensor (manufactured by Nitta Corporation). The measurement conditions are as follows: measurements are taken at 0.5 mm intervals in the transport direction and at 2 mm intervals in the direction perpendicular to the transport direction. The maximum surface pressure in the transport direction of the recording material at the fixing nip section N is the maximum value of the pressure distribution in the transport direction passing through the center A in the paper-passing area of ​​the nip section N. Here, the center A is the center in the longitudinal direction in the paper-passing area of ​​the nip section N. The paper-passing area of ​​the nip section N is the area of ​​the nip section N through which the recording material to be fixed by the fixing device 40 can pass.

[0098] 45 is a contact thermometer (thermistor) that measures the temperature of the fixing film 41 heated by the heater 43 and passes the detection result to a temperature control means (not shown). 46 is a heater holder, which is a component that holds the heater 43 when it has been heated to a high temperature.

[0099] The methods for measuring each physical property in this disclosure are shown below. <Measurement of thermal conductivity in the thickness direction of the elastic layer> The thermal conductivity λ in the thickness direction of the elastic layer is calculated using the following formula. λ = α × C p ×ρ In the formula, λ is the thermal conductivity in the thickness direction of the elastic layer (W / (m·K)), and α is the thermal diffusivity in the thickness direction (m 2 / s), C p ρ is the specific heat at constant pressure (J / (kg·K)), and ρ is the density (kg / m³). 3 ) Here, the thermal diffusivity in the thickness direction is α and the specific heat at constant pressure is C. p The values ​​of ρ and density are determined by the following method.

[0100] ·Thermal diffusivity α The thermal diffusivity α in the thickness direction of the elastic layer is measured at room temperature (25°C) using a periodic heating method thermophysical property measuring device (product name: FTC-1, manufactured by Advance Riko Co., Ltd.). Five sample pieces with an area of ​​8 × 12 mm are cut from the elastic layer using a cutter, and the thickness of each sample piece is measured using a digital length measuring instrument (product name: DIGIMICRO MF-501, flat measuring probe φ4 mm, manufactured by Nikon). Next, five measurements are taken for each sample piece, and the average value (m) is calculated. 2 The value ( / s) is calculated. The measurement is performed while applying pressure to the sample piece using a 1 kg weight.

[0101] • Constant pressure specific heat C p The constant-pressure specific heat of the elastic layer is measured using a differential scanning calorimetry analyzer (product name: Q2000, manufactured by TA Instruments). Specifically, aluminum pans are used as the sample pan and the reference pan. First, as a blank measurement, both pans are kept at a constant temperature of 15°C for 10 minutes with no pans inside, then the temperature is increased to 215°C at a rate of 10°C / minute, and the measurement is performed using a program that keeps the temperature at 215°C for another 10 minutes. Next, 10 mg of synthetic sapphire with a known constant-pressure specific heat is used as the reference material, and measurements are performed using the same program. Then, 10 mg of the measurement sample, the same amount as the reference synthetic sapphire, is cut from the elastic layer, placed in the sample pan, and measurements are performed using the same program. The measurement results were analyzed using the specific heat analysis software attached to the differential scanning calorimetry device described above, and the constant-pressure specific heat C at 25°C was calculated from the average of the five measurement results. p Calculate.

[0102] ·Density ρ The density of the elastic layer is measured using a dry automatic densimeter (product name: Accupic II 1340, manufactured by Shimadzu Corporation). Specifically, 10cm 3Using a sample cell, a sample piece is cut from the elastic layer to fill approximately 80% of the cell volume. After measuring the mass of this sample piece, it is placed in the sample cell. This sample cell is then set in the measuring section of the apparatus, and after nitrogen gas purging, volume measurements are performed 10 times. For each measurement, the density of the elastic layer is calculated from the mass of the sample piece and the measured volume, and the average value is determined. Unit-converted specific heat C of an elastic layer at constant pressure p (J / (kg·K)) and density ρ(kg / m³) 3 ), and the measured thermal diffusivity α(m 2 The thermal conductivity λ in the thickness direction of the elastic layer is calculated from ( / s).

[0103] <Measurement of filler content> A 6g sample is taken from the elastic layer and immersed in a silicone resin solvent (product name: eSolve 21RS, manufactured by Kaneko Chemical Co., Ltd.) to dissolve the silicone rubber and extract the filler. The extracted filler is washed with toluene, dried at 25°C for 1 hour, and its mass is measured. Next, the density of the filler is measured using a dry automatic densimeter (product name: Accupic II 1340, manufactured by Shimadzu Corporation). From the mass and density values ​​of the filler contained in the 6g elastic layer obtained in this way, the filler content (volume %) of the elastic layer is determined.

[0104] <Content V A , content V B Calculation of average aspect ratio > First, the filler collected during the measurement of the filler content is dispersed in toluene to prepare a dispersion. This dispersion is then applied to a substrate (aluminum foil) and dried to prepare a sample for observation using a field emission scanning electron microscope (FE-SEM). The concentration of the dispersion is adjusted so that the filler particles do not overlap and can be observed individually. Next, the observation sample is placed on a 45° inclined sample stage, and the filler is observed using an FE-SEM (product name: SU8220, manufactured by Hitachi High-Tech Corporation) under the following conditions.

[0105] (SEM observation conditions) Acceleration voltage: 2.0kV WD: 12mm Sample tilt angles: 45°, -45° The observation magnification is appropriately adjusted according to the size of the filler. By observing under the above conditions, observations can be made on the upper surface and the side surface of the sample for observation. For each filler, an observation image in which the entire upper surface and the entire side surface are captured is obtained, and the major diameter d1 and the minor diameter d2 are obtained from the observation image of the upper surface, and the thickness h is obtained from the observation image of the side surface.

[0106] (Method for calculating the major diameter d1 and the minor diameter d2) Regarding the observation image of the upper surface of the filler, after performing binarization processing using the image analysis software "ImageJ" so that the filler part is white and the part other than the filler is black, an elliptical approximation of the filler is performed to obtain the major diameter d1 and the minor diameter d2. Specifically, first, select Analyze - Set Scale in the ImageJ software and set the actual length per pixel using the scale bar in the SEM observation condition display section.

[0107] Next, select Image - Adjust - Threshold and specify the luminance threshold value so that only the filler part is selected. Then, select Analyze - Set Measurements, check Fit ellipse, select Analyze - Analyze Particles, and set the output Major value as the major diameter d1 of the filler and the Minor value as the minor diameter d2 of the filler.

[0108] (Method for calculating the thickness h) Regarding the observation image of the side surface of the filler, the height of the filler from the base material surface of the sample for observation is defined as the thickness h.

[0109] As described above, the major diameter d1, the minor diameter d2, and the thickness h are obtained, and the volume V f and the particle size R f of the filler are calculated. Also, among the values obtained by dividing the d1 of each filler by d2 or h, the larger value is defined as the aspect ratio of the filler. Volume V f= 3.14×d1 / 2×d2 / 2×h Particle size R f = (Vf×6 / 3.14) 1 / 3 The above V f , R f , the aspect ratio is determined for each of 100 fillers, and if the particle size R f is 10 to 40 μm, it is defined as filler A, and if the particle size R f is 3 μm or more and less than 10 μm, it is defined as filler B. The total volume V f of filler A, the total volume V f of filler B, and the total volume V f of all fillers are determined, and V A and V B are calculated respectively by the following formula. V A =(Volume percentage of filler)×(Total volume V f of filler A) / V V B =(Volume percentage of filler)×(Total volume V f of filler B) / V Also, for each of filler A and filler B, the arithmetic mean of the aspect ratio is determined and defined as the average aspect ratio of filler A and filler B. Further, from the volumes V f of 100 fillers, the total of the volume V f of filler A and the volume V f of filler B is divided by the total volume V f of all fillers to calculate the value V A+B .

[0110] <Calculation of average orientation angle θ of filler Ave > The average orientation angle θ Ave of the filler is calculated by performing image analysis using a binary image obtained from a cross-sectional image of the elastic layer. Specifically, it is as follows.

[0111] (Preparation of measurement cross-section) As shown in Figure 5, the plane in the thickness direction-circumferential direction of the fixing member 41 as an electrophotographic component is defined as the first plane, and the planes obtained by rotating the first plane by 10° in the thickness direction-axial direction of the fixing member 1 are defined as the second to tenth planes. As shown in Figure 6, the fixing member 41 is sliced ​​crosswise in the axial direction with a width of 500 μm or more, passing through the midpoint of the fixing member 41, and then cut open in the axial direction to obtain a strip-shaped sample. Then, the strip-shaped sample is divided into 10 equal areas in the circumferential direction, and cross-sections cut out from each area with a length of 500 μm or more, parallel to the 1st to 10th planes of the fixing member 1 and passing through the midpoint of the fixing member in the axial direction, are designated as the 1st to 10th cross-sections. When cutting out the cross-section, a cross-sectional sample is obtained using sharp scissors. Then, a cross-section formation method using an ion beam is employed. By using an ion beam cross-section formation method, it is possible to prevent the shedding of fillers and the inclusion of excess components such as abrasives, which tend to occur during cross-sectional polishing, and to form a cross-section with fewer polishing marks. A cross-section polisher (IM4000+, manufactured by Hitachi High-Tech Corporation) is used for the ion beam cross-section formation process.

[0112] (Observation and binarization of cross-sectional images) Next, the obtained cross-section is observed with a laser microscope (OPTELICS H1200, Lasertec Corporation), and after automatic correction of contrast and brightness, a cross-sectional image is acquired covering the entire elastic layer thickness direction and a 500 μm region perpendicular to the thickness. At this time, the midpoint of the 500 μm region perpendicular to the thickness is made to coincide with the axial midpoint of the fixing member.

[0113] The obtained images are then subjected to a black and white binarization process using commercially available image analysis software, so that the filler parts appear white and the silicone rubber parts appear black. The image analysis software used is "ImageJ". Using the "Otsu" method, perform binarization so that the filler portion becomes white and the non-filler portion becomes black. Specifically, in ImageJ, select Analyze-Set Scale and set the actual length per pixel using the image scale bar. Select Image-Adjust-Brightness / Contrast and press Auto to perform automatic correction of contrast and brightness. If automatic correction is not successful, perform manual correction. Next, select Image-Adjust-Threshold and select "Otsu" as the binarization method and perform binarization. For the image used for analysis, select an image in which only the elastic layer is visible as much as possible.

[0114] (θ Ave (Calculation of) For each filler in the 10 obtained cross-sectional binarized images, an ellipse approximation is performed, and the major axis a, minor axis b, and the angle θ between the major axis and the thickness direction of the elastic layer (called the filler orientation angle) are calculated using image analysis software. Specifically, after acquiring the binarized images in ImageJ as described above, select Analyze-Set Measurements, check Fit ellipse, select Analyze-Analyze Particles, and set the output Major value as the major axis a, the Minor value as the minor axis b, and the Angle value as θ. In this case, the filler orientation angle θ = 0° is defined as the case when the major axis of the elliptical filler is parallel to the thickness direction of the elastic layer, and θ = 90° is defined as the case when the major axis of the filler is perpendicular to the thickness direction of the elastic layer. The value is then converted so that the range of θ is 0 to 90°. Therefore, the closer the filler orientation angle is to 0°, the more the filler is oriented in the thickness direction.

[0115] Using the major axis length and minor axis length calculated from 10 cross-sectional images, the major axis length a / minor axis length b value is calculated, and data is extracted only for fillers where the major axis length a / minor axis length b value is 3.0 or greater. The average of the orientation angles θ of all fillers with a major axis length / minor axis length of 3.0 or greater extracted from the 10 cross-sectional images is used as the average orientation angle θ of the filler relative to the thickness direction of the elastic layer.Ave Let's assume that.

[0116] <Measurement of the thickness of the elastic layer> Average orientation angle θ of the filler Ave The thickness of the elastic layer is calculated from the cross-sectional images of the 1st to 10th sections obtained during the calculation. The arithmetic mean of the 10 sections is used.

[0117] <Measurement of the elastic modulus of an elastic layer> The tensile modulus is measured using the method described below and is used as the modulus of the elastic layer. A sample piece is cut from the elastic layer using a punching die (dumbbell-shaped die No. 8 as specified in JIS K6251:2004), and the thickness is measured near the center, which is the measurement point. Next, the cut sample piece is tested using a precision universal testing machine (product name: Autograph AG-X, manufactured by Shimadzu Corporation) at a tensile speed of 200 mm / min and room temperature. The tensile modulus is calculated by creating a graph from the measurement results with the strain of the sample piece on the horizontal axis and the tensile stress on the vertical axis, and approximating the measurement data linearly in the strain range of 0 to 10%. The arithmetic mean of 10 sample pieces is used. [Examples]

[0118] The present disclosure will be described in further detail below with reference to examples and comparative examples, but the embodiments of the present disclosure are not limited thereto.

[0119] (Classification of fillers) Spherical alumina particles (product names: Alnabeads CB-P05, CB-P10, CB-P15, manufactured by Resonaq Corporation), and granular boron nitride particles (product names: SGP, XGP, manufactured by Denka Corporation) Using as a raw material, filler 1 having a desired particle size distribution is obtained by classifying the filler. I obtained ~16.

[0120] The classification process used an inertial classification elbow jet (manufactured by Nippon Steel Mining Co., Ltd.), with operating conditions of a feed rate of 5 kg / hr. The F classification edge (fine particle classification edge) and G classification edge (coarse particle classification edge) were adjusted to obtain the desired particle size distribution.

[0121] For each of the obtained fillers 1 to 16, the V A , V B Then, using the same method as for calculating the average aspect ratio, V was calculated for 100 fillers. f and R f The values ​​for the 50% particle size (D50), 10% particle size (D10), and 90% particle size (D90) based on volume distribution were calculated. The raw materials for fillers 1 to 16, as well as D50, D10, and D90, are shown in Table 1.

[0122] <Example 1> In this example, a fixing film as shown in Figure 3 was prepared. (base material) A stainless steel (SUS) material with an inner diameter of 24 mm and a thickness of 30 μm was used as the base material. Specifically, a SUS endless belt with an inner diameter of 24 mm, a width of 400 mm, and a thickness of 30 μm was used as the base material. During the manufacturing process, the endless belt was handled with a core inserted inside.

[0123] (Formation of the internal sliding layer) First, an approximately equimolar amount of an aromatic tetracarboxylic dianhydride or its derivative was reacted with an aromatic diamine in an aprotic polar organic solvent to obtain a polyimide precursor solution. The obtained polyimide precursor solution was applied to the inner surface of a substrate by the ring coating method, the solvent was dried in an electric furnace, and then the inner sliding layer was formed by heating at 260-400°C for about 1 hour. The thickness of the inner sliding layer was 12 μm.

[0124] (Preparation of silicone rubber mixture) A liquid addition-curing silicone rubber mixture was prepared by mixing the following components (a) to (d) using the procedure described below. Component (a): Linear organopolysiloxane having unsaturated aliphatic groups Component (b): Organopolysiloxane having active hydrogen bonded to silicon Component (c): Catalyst Ingredient (d): Filler

[0125] First, 100 parts by mass of a silicone polymer was prepared as component (a), which has vinyl groups, which are unsaturated aliphatic groups, only at both ends of the molecular chain, and methyl groups as unsubstituted hydrocarbon groups that do not contain any other unsaturated aliphatic groups. This silicone polymer (product name: DMS-V35, manufactured by Gelest, viscosity 5000 mm) 2 From now on, / s will be referred to as "Vi". Next, 87.1 parts by mass of filler 1 and 50.7 parts by mass of filler 14 were added to Vi as component (d), and the mixture was placed in a self-rotating mixer (Sinky Co., Ltd., ARV-5000) and stirred and mixed at 600 rpm for 2 minutes to obtain mixture 1.

[0126] Next, 0.2 parts by mass of 1-ethynyl-1-cyclohexanol (manufactured by Tokyo Chemical Industry Co., Ltd.), a curing retarder, was dissolved in the same weight of toluene, and this solution was added to mixture 1 to obtain mixture 2. Next, 0.1 parts by mass of a hydrosilylation catalyst (platinum catalyst: a mixture of 1,3-divinyltetramethyldisiloxane platinum complex, 1,3-divinyltetramethyldisiloxane, and 2-propanol) was added to mixture 2 as component (c) to obtain mixture 3. Furthermore, component (b) is a silicone polymer with a linear siloxane skeleton and active hydrogen groups bonded to silicon only in the side chains (product name: HMS-301, manufactured by Gelest, viscosity 30 mm). 2 1.3 parts by mass of (hereinafter referred to as "SiH") was weighed out. This was then mixed. By adding it to substance 3 and mixing thoroughly, a liquid addition-curing type silicone rubber mixture was obtained.

[0127] (Formation of primer layer and elastic layer) A primer layer and an elastic layer were formed on a substrate with an internal sliding layer using the following procedure. A hydrosilyl-based silicone primer (DY39-051 A / B; manufactured by Dow-Toray) was applied almost uniformly to the outer surface of the substrate to a dry weight of 20 mg. After drying the solvent, the substrate was baked in an electric furnace set to 160°C for 30 minutes. The above silicone rubber mixture was applied to this primer-treated substrate to a thickness of 250 μm using the ring-coating method. This is referred to as an uncured endless belt.

[0128] Next, a corona charger with a charging area width of 295 mm was positioned opposite the uncured endless belt along its busbar, and an AC electric field was applied to the surface of the uncured elastic layer while the uncured endless belt was rotated at 100 rpm. The conditions were: supply current of ±150 μA to the discharge wire of the corona charger, voltage applied to the grid of ±1500 V (Vp-p: 3000 V), frequency of 0.025 Hz, charging time of 160 seconds, and distance of 3 mm between the grid electrode and the belt.

[0129] The charged, uncured endless belt was heated in an electric furnace at 160°C for 1 minute (primary curing), and then heated in an electric furnace at 200°C for 30 minutes (secondary curing) to cure the silicone rubber mixture, thereby obtaining an endless belt with a cured elastic layer.

[0130] (Application of adhesive layer) An addition-curing silicone rubber adhesive (product name: SE1819CV A / B; manufactured by Toray Dow Corning Co., Ltd.) was applied almost uniformly to the surface of the elastic layer of the cured endless belt to a thickness of approximately 10 μm.

[0131] (Formation of the surface layer) After applying the adhesive, PFA (product name: AP-231SH; manufactured by Daikin Industries, Ltd.) was extruded as a surface layer to an inner diameter of 23 mm and a thickness of 20 μm, and the inner surface was etched to obtain a fluororesin tube. The fluororesin tube was then coated onto the adhesive by vacuum expansion from the outside (vacuum expansion coating method). Subsequently, the belt surface was uniformly rubbed from above the fluororesin tube to remove excess adhesive from between the elastic layer and the fluororesin tube, reducing the thickness to approximately 5 μm.

[0132] The adhesive was cured by heating this endless belt in an electric furnace set to 200°C for one hour, thereby fixing the fluororesin tube onto the elastic layer. The ends of the resulting endless belt were cut to obtain a fixing film with a width of 336.5 mm.

[0133] The thermal conductivity λ in the thickness direction of the elastic layer of the fabricated fixing film, the filler content, and V A , V B , average aspect ratio of fillers A and B, θ Ave The thickness of the elastic layer and the elastic modulus of the elastic layer were determined. Furthermore, the V of fillers A and B was also determined. f The sum of the V values ​​for each of the fillers f The value V divided by the sum V A+B The following was calculated. Furthermore, durability was evaluated based on the following evaluation method. These results are shown in Table 2.

[0134] <Durability> Durability was evaluated using the film heating type fixing device 40 shown in Figure 2, which incorporates the fabricated fixing film, and the following evaluation was performed. First, the size of the contact area between the fixing film and the pressure roller was set to 10 mm in the transport direction and 330 mm in the direction perpendicular to the transport direction. Then, the pressure distribution profile in the transport direction of the fixing nip section N was set so that the maximum surface pressure in the transport direction of the recording material at the fixing nip section N was 0.35 MPa. I set the code.

[0135] Subsequently, the evaluation was conducted under the following conditions. Test environment: Room temperature 23°C, relative humidity 50% Process speed: 200 mm / sec Print speed: 30 pages / minute Surface temperature of the paper feeding section of the fixing film: 170℃ Paper feeding conditions: Continuously feed paper (A4 landscape, GF-C068). If the evaluation criteria below result in an A to C rating, it is determined that the effects of this disclosure have been achieved. (Evaluation Criteria) A: The elastic layer does not break even after passing over 400,000 sheets of paper through it. B: The elastic layer will not break even when passing between 300,000 and 400,000 sheets of paper. C: The elastic layer does not break even when passing between 250,000 and 300,000 sheets of paper. D: The elastic layer ruptures after less than 250,000 sheets of paper are passed through.

[0136] <Examples 2-17, Comparative Examples 1-11> Examples 2-17 and Comparative Examples 1-11 were obtained in the same manner as in Example 1, except that the type of filler used, the amount of filler added, and the voltage applied to the grid were changed as shown in Table 2. In Comparative Example 9, a fixed film was obtained in the same manner as in Example 2, except that an AC electric field was not applied to the surface of the elastic layer of the uncured endless belt before curing.

[0137] In Examples 2-17 and Comparative Examples 1-11, the thermal conductivity λ in the thickness direction of the elastic layer of the prepared fixing film, the filler content, and V were determined. A , V B , average aspect ratio of fillers A and B, θ AVE The thickness of the elastic layer and the elastic modulus of the elastic layer were determined. Furthermore, the V of fillers A and B was also determined. f The sum of the V values ​​for each of the fillers f The value V divided by the sum V A+B The following was calculated. Furthermore, durability was evaluated based on the same evaluation method as in Example 1. These results are shown in Table 2.

[0138] [Table 1]

[0139] [Table 2]

[0140] In the table, voltage indicates the voltage applied to the grid. Filler amount represents the filler content in the elastic layer. arA is the average aspect ratio of filler A, and arB is the average aspect ratio of filler B.

[0141] This disclosure relates to the following configuration. (Composition 1) An electrophotographic component which is a rotating body having a base material and an elastic layer provided on the outer circumference of the base material, The elastic layer comprises rubber and fillers dispersed in the rubber. The filler content in the elastic layer is 15 to 50% by volume. Of these fillers, those with a particle size of 10 to 40 μm are designated as filler A. When filler B is defined as having a particle size of 3 μm or more and less than 10 μm, The content V of filler A in the elastic layer A However, it is 7-30% by volume. The average aspect ratio of filler A is 5.0 to 40.0. The content of filler B in the elastic layer V B However, it is 7-30% by volume. The average aspect ratio of filler B is 1.0 to 2.0. The plane in the thickness-circumferential direction of the elastic layer is defined as the first plane, and the planes obtained by rotating the first plane by 10° in the thickness-axial direction of the elastic layer are defined as the second to tenth planes. Cross-sectional images of the elastic layer with a size of 500 μm across the entire thickness of the elastic layer are acquired as the first to tenth cross-sectional images, such that they are parallel to the first to tenth planes and the center of the direction perpendicular to the thickness direction of the elastic layer coincides with the center of the electrophotographic member in the axial direction. The first to tenth cross-sectional images are each binarized to obtain the first to tenth binarized images. In the first to tenth binarized images, when the shape of the filler is approximated as an ellipse, The average orientation angle θ of the elliptical filler with respect to the thickness direction of the elastic layer, where the ratio of the major axis length to the minor axis length is 3.0 or greater. Ave An electrophotographic component characterized by having an angle of 0 to 45 degrees. (Configuration 2) The electrophotographic member according to configuration 1, wherein the filler A includes a flat plate-shaped filler. (Composition 3) The average orientation angle θ Ave The electrophotographic component according to configuration 1 or 2, wherein the angle is 0 to 40°. (Composition 4) The electrophotographic component according to any of configurations 1 to 3, wherein the average aspect ratio of the filler A is 10.0 to 40.0. (Composition 5) The content of the filler in the elastic layer is 20 to 40% by volume. Said content V A However, it is 10-20% by volume. Said content V B However, the electrophotographic component is present in an amount of 10-20% by volume, as described in any of configurations 1-4. (Composition 6) An electrophotographic member according to any of configurations 1 to 5, wherein the thermal conductivity in the thickness direction of the elastic layer is 1.40 W / (m·K) or more. (Composition 7) The electrophotographic member according to any one of configurations 1 to 6, wherein the filler A comprises a flat plate-shaped boron nitride. (Composition 8) The electrophotographic member according to any one of configurations 1 to 7, wherein the elastic modulus of the elastic layer is 0.60 to 2.00 MPa. (Composition 9) The electrophotographic member according to any one of configurations 1 to 8, wherein the thickness of the elastic layer is 150 to 500 μm. (Composition 10) The electrophotographic member described in any of configurations 1 to 9, wherein the electrophotographic member is a fixing member. (Configuration 11) Fixing member and A pressing member that faces the fixing member and forms a fixing nip portion that clamps and transports the recording material carrying the toner image between itself and the fixing member, A fixing device having, A fixing device in which at least one of the fixing member and the pressurizing member is an electrophotographic member as described in any of configurations 1 to 9. (Composition 12) The fixing device according to configuration 11, wherein the maximum surface pressure in the direction of transport of the recording material at the fixing nip section is 0.25 to 0.40 MPa. (Composition 13) An electrophotographic image forming apparatus equipped with a fixing device, An electrophotographic image forming apparatus characterized in that the fixing device is the fixing device described in configuration 11 or 12. [Explanation of Symbols]

[0142] 10: Image forming unit, 11: Photosensitive drum, 12: Charger, 13: Laser scanner, 14: Developer, 15: Cleaner, 17: Primary transfer blade, 20: Paper feed cassette, 25: Multi-purpose paper feed tray, 23: Resist roller pair, 31: Intermediate transfer belt, 35: Secondary transfer roller, 40: Fixing unit, 41: Fixing film, 41a: Surface layer, 41b: Substrate, 41c: Elastic layer, 43: Heating element, 44: Pressure roller, 45: Contact thermistor, 46: Heater holder, P: Recording material, T: Toner, N: Fixing nip section

Claims

1. An electrophotographic component which is a rotating body having a base material and an elastic layer provided on the outer circumference of the base material, The elastic layer comprises rubber and fillers dispersed in the rubber. The content of the filler in the elastic layer is 15 to 50% by volume. Of these fillers, those with a particle size of 10 to 40 μm are designated as filler A. When filler B is defined as having a particle size of 3 μm or more and less than 10 μm, The content V of the filler A in the elastic layer Ａ However, it is 7-30% by volume. The average aspect ratio of filler A is 5.0 to 40.

0. The content V of the filler B in the elastic layer Ｂ However, it is 7-30% by volume. The average aspect ratio of filler B is 1.0 to 2.

0. The plane in the circumferential direction of the thickness of the elastic layer is defined as the first plane, and the planes obtained by rotating the first plane by 10° in the axial direction of the thickness of the elastic layer are defined as the second to tenth planes. Cross-sectional images of the elastic layer with a size of 500 μm across the entire thickness of the elastic layer are acquired as the first to tenth cross-sectional images, such that they are parallel to the first to tenth planes and the center of the direction perpendicular to the thickness direction of the elastic layer coincides with the center of the electrophotographic member in the axial direction. The first to tenth cross-sectional images are each binarized to obtain the first to tenth binarized images. In the first to tenth binarized images, when the shape of the filler is approximated by an ellipse, The average orientation angle θ of the elliptical filler with respect to the thickness direction of the elastic layer, where the ratio of the major axis length to the minor axis length is 3.0 or greater. Ａｖｅ An electrophotographic component characterized by having an angle of 0 to 45°.

2. The electrophotographic member according to claim 1, wherein the filler A includes a flat plate-shaped filler.

3. The average orientation angle θ Ａｖｅ The electrophotographic member according to claim 1 or 2, wherein the angle is 0 to 40°.

4. The electrophotographic member according to claim 1 or 2, wherein the average aspect ratio of the filler A is 10.0 to 40.

0.

5. The content of the filler in the elastic layer is 20 to 40% by volume. The content V Ａ However, it is 10-20% by volume. The content V Ｂ The electrophotographic member according to claim 1 or 2, wherein the amount is 10 to 20 volume percent.

6. The electrophotographic member according to claim 1 or 2, wherein the thermal conductivity in the thickness direction of the elastic layer is 1.40 W / (m·K) or more.

7. The electrophotographic member according to claim 1 or 2, wherein the filler A contains a flat plate-shaped boron nitride.

8. The electrophotographic member according to claim 1 or 2, wherein the elastic modulus of the elastic layer is 0.60 to 2.00 MPa.

9. The electrophotographic member according to claim 1 or 2, wherein the thickness of the elastic layer is 150 to 500 μm.

10. The electrophotographic member according to claim 1 or 2, wherein the electrophotographic member is a fixing member.

11. Fixing member and A pressing member that faces the fixing member and forms a fixing nip portion that clamps and transports the recording material carrying the toner image between itself and the fixing member, A fixing device having, A fixing device in which at least one of the fixing member and the pressurizing member is the electrophotographic member described in claim 1 or 2.

12. The fixing device according to claim 11, wherein the maximum surface pressure in the direction of transport of the recording material at the fixing nip portion is 0.25 to 0.40 MPa.

13. An electrophotographic image forming apparatus equipped with a fixing device, An electrophotographic image forming apparatus characterized in that the fixing device is the fixing device described in claim 11.

Images