Fixing belt, fixing device, and image forming apparatus

Abstract

To provide a fixing belt which can suppress off-set even using a recording medium having large surface unevenness.SOLUTION: A fixing belt 110 has a resin base material layer 110A, an elastic layer 110B, and a release layer 110C in this order, wherein the elastic layer 110B includes an elastic material and an aggregate in which a plurality of fibrous carbons is tangled with each other, and a maximum diameter of the aggregate is 15% or less of a film thickness of the elastic layer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a fixing belt, a fixing device, and an image forming apparatus. [Background technology]

[0002] 2. Description of the Related Art In image forming apparatuses (such as copiers, facsimiles, and printers) using an electrophotographic method, a fixing belt is used to fix a toner image formed on a recording medium onto the recording medium.

[0003] Patent Document 1 discloses a functional membrane containing aggregates of entangled carbon nanotubes, each having a diameter of 50 μm or less, a height of less than 5 μm, and a ratio of the height to the diameter (height / diameter) of less than 0.1. Moreover, Patent Document 1 discloses a polyimide tube obtained by dispersing carbon nanotubes as needle-like highly thermally conductive fillers in a polyimide resin. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-140105 A [Patent Document 2] JP 2011-186127 A Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present disclosure is to provide a fixing belt that can suppress offset even when a recording medium with large surface irregularities is used, compared to a case in which the elastic layer contains only unentangled fibrous carbon as the fibrous carbon, or contains aggregates formed by multiple entangled fibrous carbons and the maximum diameter of such aggregates exceeds 15% of the elastic layer thickness. [Means for solving the problem]

[0006] Specific means for solving the above problems include the following aspects. <1> The film has a resin substrate layer, an elastic layer, and a release layer in this order, The elastic layer includes an elastic material and an aggregate formed by entangling a plurality of fibrous carbon fibers with each other, and the maximum diameter of the aggregate is 15% or less of the thickness of the elastic layer.

[0007] <2> The elastic layer further comprises non-entangled fibrous carbon. <1> The fixing belt according to claim 1. <3> When the content of the aggregate is A and the content of the fibrous carbon that is not entangled with each other is B, the relationship of A ≧ B is satisfied on a mass basis. <2> The fixing belt according to claim 1. <4> A ratio (A / (A+B)) of the content A of the aggregate to the total content A of the aggregate and the content B of the fibrous carbon not entangled with each other is 0.50 or more and 0.95 or less on a mass basis. <2> or <3> The fixing belt according to claim 1. <5> The content of the aggregate is 0.1% by mass or more and 40% by mass or less with respect to the total mass of the elastic layer. <1> ~ <4> 13. The fixing belt according to claim 12, <6> The content of the aggregate is 10% by mass or more and 30% by mass or less with respect to the total mass of the elastic layer. <5> The fixing belt according to claim 1. <7> The Young's modulus of the elastic layer is 0.2 MPa or more and 1.0 MPa or less. <1> ~ <6> 13. The fixing belt according to claim 12, <8> The fibrous carbon is a carbon nanotube. <1> ~ <7> 13. The fixing belt according to claim 12,

[0008] <9> The film has a resin substrate layer, an elastic layer, and a release layer in this order, The elastic layer of the fixing belt includes an elastic material and fibrous carbon, and has a thermal conductivity of 1.0 W / m·K or more and 4.5 W / m·K or less, and a Young's modulus of 0.2 MPa or more and 1.0 MPa or less.

[0009] <10> A first rotating body and a second rotating body arranged in contact with an outer surface of the first rotating body, At least one of the first rotating body and the second rotating body is the fixing belt according to any one of <1> to <9>, A fixing device that fixes the toner image by inserting a recording medium having a toner image formed on its surface into a contact portion between the first rotating body and the second rotating body. <11> An image carrier, Charging means for charging the surface of the image carrier, Electrostatic latent image forming means for forming an electrostatic latent image on the charged surface of the image carrier, Developing means for developing the electrostatic latent image formed on the surface of the image carrier with a developer containing toner to form a toner image, Transferring means for transferring the toner image onto the surface of a recording medium, Fixing means composed of the fixing device according to <10> for fixing the toner image onto the recording medium, An image forming apparatus comprising the same.

Advantages of the Invention

[0010] According to the invention according to <1>, when the elastic layer contains only fibrous carbon that is not intertwined with each other as fibrous carbon, or when it contains an aggregate formed by intertwining of a plurality of fibrous carbons, and the maximum diameter of such an aggregate exceeds 15% of the elastic layer film thickness, a fixing belt capable of suppressing offset can be provided even when using a recording medium with large surface irregularities.

[0011] According to the invention according to <2>, a fixing belt having a high thermal conductivity is provided as compared with the case where it contains an aggregate formed by intertwining of a plurality of fibrous carbons and does not contain fibrous carbon that is not intertwined with each other. According to the invention according to <3>, a fixing belt having a high thermal conductivity is provided as compared with the case where the content A of the aggregate and the content B of the fibrous carbon that is not intertwined with each other satisfy the relationship A < B on a mass basis. According to the invention according to <4>, a fixing belt having a high thermal conductivity is provided as compared with the case where the ratio (A / (A + B)) is less than 0.5 on a mass basis. <5> or <6> According to the present invention, a fixing belt is provided that can suppress offset even when a recording medium with large surface irregularities is used, compared to when the content of the aggregate exceeds 40 mass % relative to the total mass of the elastic layer. <7> According to the present invention, there is provided a fixing belt which can suppress offset even when a recording medium having a large surface unevenness is used, as compared with a case where the Young's modulus of the elastic layer is more than 1.0 MPa. <8> According to the present invention, there is provided a fixing belt which can suppress offset even when a recording medium having a large surface irregularity is used, as compared with a case where the fibrous carbon is not carbon nanotubes.

[0012] <9> According to the present invention, there is provided a fixing belt in which the elastic layer contains an elastic material and fibrous carbon, and which can suppress offset even when a recording medium with large surface irregularities is used, compared to a case in which the thermal conductivity is less than 1.0 W / m·K or the Young's modulus exceeds 1.0 MPa.

[0013] <10> or <11> According to the invention, there is provided a fixing device or an image forming apparatus equipped with a fixing belt that can suppress offset even when a recording medium with large surface irregularities is used, compared to when the elastic layer contains only unentangled fibrous carbon as fibrous carbon, or contains aggregates formed by multiple entangled fibrous carbons and the maximum diameter of such aggregates exceeds 15% of the elastic layer thickness. [Brief description of the drawings]

[0014] [Figure 1] 1 is a schematic cross-sectional view illustrating an example of a fixing belt according to the present disclosure. [Diagram 2] 1 is a schematic configuration diagram illustrating an example of a fixing device according to a first embodiment of the present disclosure. [Diagram 3] FIG. 11 is a schematic configuration diagram illustrating an example of a fixing device according to a second embodiment of the present disclosure. [Figure 4] FIG. 11 is a schematic configuration diagram illustrating an example of a fixing device according to a third embodiment of the present disclosure. [Diagram 5] 1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, embodiments of the present invention will be described. These descriptions and examples are merely illustrative of the embodiments, and are not intended to limit the scope of the embodiments.

[0016] In the present specification, in which numerical ranges are described in stages, the upper limit or lower limit value described in one numerical range may be replaced with the upper limit or lower limit value of another numerical range described in stages. In addition, in the numerical ranges described in this specification, the upper or lower limit of the numerical ranges may be replaced with values ​​shown in the examples.

[0017] In this specification, each component may contain multiple corresponding substances. In this specification, when referring to the amount of each component in a composition, if multiple substances corresponding to each component are present in the composition, the amount refers to the total amount of those multiple substances present in the composition, unless otherwise specified.

[0018] In this specification, unless otherwise specified, when the term "fixing belt according to the present disclosure" is used, it refers to both the first and second embodiments described below.

[0019] <Fixing belt> A first embodiment of a fixing belt according to the present disclosure has, in this order, a resin substrate layer, an elastic layer, and a release layer, the elastic layer including an elastic material and an aggregate formed by entangling a plurality of fibrous carbons with each other, the maximum diameter of the aggregate being 15% or less of the thickness of the elastic layer. A second embodiment of a fixing belt according to the present disclosure has a resin substrate layer, an elastic layer, and a release layer, in that order. The elastic layer contains an elastic material and fibrous carbon, and has a thermal conductivity of 1.0 W / m·K or more and 4.5 W / m·K or less, and a Young's modulus of 0.2 MPa or more and 1.0 MPa or less. Hereinafter, an aggregate formed by a plurality of fibrous carbons entangled with one another will also be referred to as a specific aggregate, as appropriate.

[0020] In the fixing belt, the elastic layer is a layer provided with the aim of imparting elasticity to the fixing belt against pressure applied from the outer circumferential side, and plays a role in adhering the surface of the fixing belt to the toner image by following the unevenness of the surface of the recording medium and the unevenness of the toner image on the recording medium. The elastic layer contains a thermally conductive material in order to improve fixability, but the harder the elastic layer is, the greater the content of the thermally conductive material. When the hardness of the elastic layer is increased, the ability to conform to the shape of the recording medium's surface irregularities is reduced, and offset may occur, particularly when a recording medium with large surface irregularities is used. Here, "offset" refers to a phenomenon in which a part of a toner image adheres to the fixing belt when the toner image is fixed to the recording medium. When this phenomenon occurs, image defects occur in the fixed image.

[0021] In the first embodiment of the fixing belt according to the present disclosure, the elastic layer includes an aggregate (i.e., a specific aggregate) formed by intertwining a plurality of fibrous carbons with each other together with the elastic material. This specific aggregate can transmit heat radially from the part where the fibrous carbons are intertwined as the starting point, so that the elastic layer has a higher thermal conductivity than when the fibrous carbons are not intertwined with each other. As a result, when the specific aggregate is used, the amount of the thermally conductive material in the elastic layer is reduced, and it is considered that sufficient thermal conductivity can be obtained without increasing the hardness of the elastic layer too much. Therefore, in the first embodiment of the fixing belt according to the present disclosure, by having the above-mentioned configuration, it is possible to obtain an elastic layer that has sufficient thermal conductivity while having excellent shape conformability to the surface unevenness of the recording medium, and it is presumed that offset can be suppressed even when a recording medium with large surface unevenness is used.

[0022] The second embodiment of the fixing belt according to the present disclosure has an elastic layer exhibiting the above-mentioned thermal conductivity and Young's modulus. The fixing belt having this elastic layer (i.e., the second embodiment of the fixing belt according to the present disclosure) has sufficient thermal conductivity and excellent shape conformability to the surface irregularities of a recording medium, and is therefore expected to be able to suppress offset even when a recording medium with large surface irregularities is used.

[0023] The fixing belt according to the present disclosure will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view showing an example of a fixing belt according to the present disclosure. The fixing belt 110 shown in FIG. 1 includes a resin substrate layer 110A, an elastic layer 110B provided on the resin substrate layer 110A, and a release layer 110C provided on the elastic layer 110B. The layer structure of the fixing belt 110 according to the present disclosure is not limited to the layer structure shown in FIG. 1, and may be a layer structure in which a metal layer and its protective layer are interposed between the base layer 110A and the elastic layer 110B, a layer structure in which an adhesive layer is interposed between the base layer 110A and the elastic layer 110B, a layer structure in which an adhesive layer is interposed between the elastic layer 110B and the release layer 110C, or a layer structure that combines these layer structures.

[0024] The components of the fixing belt according to the present disclosure will be described in detail below, with the reference numerals omitted.

[0025] First, we will explain the elastic layer in a first embodiment of the fixing belt according to the present disclosure (hereinafter also referred to as elastic layer (1)) and the elastic layer in a second embodiment of the fixing belt according to the present disclosure (hereinafter also referred to as elastic layer (2)).

[0026] [Elastic layer (1)] The elastic layer (that is, the elastic layer (1)) in the first embodiment of the fixing belt according to the present disclosure includes an elastic material and an aggregate (that is, a specific aggregate) in which a plurality of fibrous carbons are entangled with one another. The maximum diameter of the aggregate is 15% or less of the thickness of the elastic layer.

[0027] [Specific aggregate] The specific aggregate in the elastic layer (1) is used as a heat conducting material. As described above, the maximum diameter of the specific aggregates may be 15% or less of the elastic layer thickness, and more preferably 10% or less of the elastic layer thickness, while the maximum diameter of the specific aggregates is preferably 2% or more of the elastic layer thickness.

[0028] Furthermore, from the viewpoint of suppressing offset, the maximum diameter of the specific aggregate is, for example, preferably 30 μm or less, more preferably 25 μm or less, even more preferably 20 μm or less, and particularly preferably 15 μm or less. The lower limit of the maximum diameter of the specific aggregates is, for example, 8 μm or more.

[0029] The specific aggregate is an aggregate formed by entangling a plurality of fibrous carbons with each other, and may have any shape as long as it has the above-mentioned maximum diameter. The specific aggregate in the fixing belt may be, for example, spherical, elliptical, or irregular in shape.

[0030] In addition, from the viewpoint of suppressing offset, the ratio of the minor axis Y to the major axis X of the specific aggregate in the elastic layer (1) (minor axis Y / major axis X) is preferably 0.1 or more and 1.0 or less, more preferably 0.1 or more and 0.8 or less, and even more preferably 0.2 or more and 0.6 or less.

[0031] The maximum diameter, major axis X, and minor axis Y of a particular aggregate are measured in the following manner. The release layer is peeled off from the fixing belt, and the surface of the exposed elastic layer is measured using a SEM (scanning electron microscope) image. The longitudinal length and the normal length of any 10 specific aggregates exposed on the surface are measured, and the arithmetic average values ​​of the maximum diameter (= major axis X) and minor axis Y of each of the 10 specific aggregates are determined. The method for peeling off the release layer from the fixing belt may be, for example, the same method as that for measuring the thermal conductivity described below.

[0032] The length of the fibrous carbon contained in the specific aggregate is preferably 0.5 μm or more and 20 μm or less, more preferably 1 μm or more and 18 μm or less, and even more preferably 2 μm or more and 15 μm or less.

[0033] The diameter of the fibrous carbon contained in the specific aggregate is preferably 20 nm or more and 300 nm or less, more preferably 25 nm or more and 250 nm or less, and even more preferably 30 nm or more and 200 nm or less.

[0034] The length and diameter of the fibrous carbon contained in the specific aggregate are measured by the following method. The release layer is peeled off from the fixing belt, and the surface of the exposed elastic layer is measured using an SEM image. The length and diameter (thickness) of 10 random carbon fibers from the specific aggregate exposed on the surface are measured, and the arithmetic average values ​​of the 10 carbon fibers are taken as the length and diameter values. The method for peeling off the release layer from the fixing belt may be, for example, the same method as that for measuring the thermal conductivity described below.

[0035] The number of fibrous carbons contained in the specific aggregate is not particularly limited as long as it is a plurality (that is, two or more).

[0036] The fibrous carbon contained in the specific polymer is preferably a carbon nanotube from the viewpoints of availability, thermal conductivity, and the like.

[0037] The content of the specific aggregate in the elastic layer (1) is preferably 0.1% by mass or more and 40% by mass or less, more preferably 5% by mass or more and 35% by mass or less, further preferably 10% by mass or more and 35% by mass or less, and particularly preferably 10% by mass or more and 30% by mass or less, based on the total mass of the elastic layer. Increasing the content of the specific polymer increases the thermal conductivity of the elastic layer (1), making it easier to suppress offset even when fixing is performed at high speed. On the other hand, by setting the content of the specific polymer to 40% by mass or less based on the total mass of the elastic layer, the conformability to the shape of the fixing belt is increased, making it easier to suppress offset even when a recording medium with large surface irregularities is used.

[0038] [Disjointed fibrous carbon] From the viewpoint of further increasing the thermal conductivity, the elastic layer (1) preferably contains non-entangled fibrous carbon in addition to the above-mentioned specific aggregates. That is, the elastic layer (1) preferably contains an elastic material, specific aggregates, and non-entangled fibrous carbon.

[0039] The length of the non-entangled fibrous carbon is preferably 0.5 μm or more and 100 μm or less, more preferably 2 μm or more and 80 μm or less, and further preferably 3 μm or more and 60 μm or less.

[0040] The diameter of the non-entangled fibrous carbon is preferably 20 nm or more and 300 nm or less, more preferably 25 μm or more and 250 μm or less, and further preferably 30 nm or more and 200 nm or less.

[0041] The fibrous carbon that is not entangled with another may be the same as or different from the fibrous carbon contained in the specific aggregate (that is, the fibrous carbon that constitutes the specific aggregate).

[0042] The unentangled fibrous carbon is preferably a carbon nanotube from the viewpoints of availability, thermal conductivity, and the like.

[0043] When the elastic layer (1) contains unentangled fibrous carbon, the content thereof is preferably more than 0 mass% and not more than 20 mass%, more preferably 0.5 mass% or more and 15 mass% or less, and even more preferably 0.5 mass% or more and 10 mass% or less, relative to the total mass of the elastic layer.

[0044] In order to increase the thermal conductivity of the belt, it is preferable that the content A of the specific aggregates and the content B of the unentangled fibrous carbon in the elastic layer (1) satisfy the relationship A≧B on a mass basis. In addition, from the viewpoint of increasing the thermal conductivity of the belt, it is preferable that the ratio (A / (A+B)) of the content A of the specific aggregates to the total content A of the specific aggregates and the content B of the unentangled fibrous carbon in the elastic layer (1) is 0.50 or more and 0.95 or less, on a mass basis.

[0045] The content A of the specific aggregates and the content B of the non-entangled fibrous carbon are measured by the following method. The release layer is peeled off from the belt, and the surface SEM image of the exposed elastic layer is subjected to image analysis to measure. The total area of ​​the specific aggregates and the total area of ​​the fibrous carbon that is not entangled with each other in the surface area of ​​the exposed elastic layer are determined by image analysis of the surface SEM image. Here, the number of measurement samples (i.e., the number of SEM images to be image analyzed) is 5. The "content A of specific aggregates" is the arithmetic average value of the "total area of ​​the specific aggregates in the surface area of ​​the elastic layer" obtained by the above method for the five samples, and the "content B of fibrous carbon that is not entangled with each other" is the arithmetic average value of the "total area of ​​the fibrous carbon that is not entangled with each other in the surface area of ​​the elastic layer" obtained by the above method for the five samples. Then, the ratio (A / (A+B)) is calculated from the "content A of specific aggregates" and the "content B of fibrous carbon not entangled with each other" obtained as described above. When calculating the ratio (A / (A+B)), if the specific gravities of the specific aggregates and the fibrous carbon not entangled with each other are different, the contents A and B may be corrected using the respective specific gravities. The method for peeling off the release layer from the fixing belt may be, for example, the same method as that for measuring the thermal conductivity described below.

[0046] [Elastic material] Examples of the elastic material contained in the elastic layer (1) include fluororesin, silicone resin, silicone rubber, fluororubber, fluorosilicone rubber, etc. Among them, as the elastic material, silicone rubber and fluororubber are preferred from the viewpoints of heat resistance, thermal conductivity, insulation, etc., and silicone rubber is more preferred.

[0047] Examples of silicone rubber include RTV silicone rubber, HTV silicone rubber, and liquid silicone rubber. Specific examples of silicone rubber include polydimethyl silicone rubber (MQ), methyl vinyl silicone rubber (VMQ), methyl phenyl silicone rubber (PMQ), and fluoro silicone rubber (FVMQ).

[0048] Silicone rubbers that are primarily crosslinked by addition reaction are preferred. Silicone rubbers are known to have various types of functional groups, and preferred examples include dimethyl silicone rubbers having methyl groups, methylphenyl silicone rubbers having methyl and phenyl groups, and vinyl silicone rubbers having vinyl groups (vinyl group-containing silicone rubbers). As the silicone rubber, a vinyl silicone rubber having a vinyl group is more preferable, and a silicone rubber having an organopolysiloxane structure having a vinyl group and a hydrogen organopolysiloxane structure having a hydrogen atom (SiH) bonded to a silicon atom is even more preferable.

[0049] Examples of the fluororubber include vinylidene fluoride rubber, tetrafluoroethylene / propylene rubber, tetrafluoroethylene / perfluoromethylvinyl ether rubber, phosphazene rubber, and fluoropolyether.

[0050] The elastic material preferably contains silicone rubber as a main component (that is, the elastic material contains silicone rubber in an amount of 50% by mass or more relative to the total mass of the elastic material). The content of the silicone rubber is more preferably 90% by mass or more, further preferably 99% by mass or more, and may be 100% by mass, based on the total mass of the elastic material used in the elastic layer (1).

[0051] [Additives] In addition to the above-mentioned components, the elastic layer may contain additives such as a specific aggregate, an inorganic filler other than fibrous carbon, a softener (e.g., paraffin-based), a processing aid (e.g., stearic acid), an antioxidant (e.g., amine-based), and a vulcanizing agent (e.g., sulfur, metal oxide, peroxide).

[0052] The thickness (film thickness) of the elastic layer in the first embodiment of the fixing belt according to the present disclosure is, for example, preferably 30 μm or more and 600 μm or less, and more preferably 100 μm or more and 500 μm or less.

[0053] [Physical Properties] (Thermal Conductivity) The elastic layer (1) preferably has high thermal conductivity. Specifically, the thermal conductivity of the elastic layer is preferably 1.0 W / m·K or more and 4.5 W / m·K or less, more preferably 2.0 W / m·K or more and 4.5 W / m·K or less, and even more preferably 3.5 W / m·K or more and 4.5 W / m·K or less.

[0054] The thermal conductivity of the elastic layer is measured as follows. First, a cutter blade is used to make an incision from the release layer side of the fixing belt to the release layer / elastic layer interface, and then the release layer is peeled off by gripping only the release layer with a hand and pulling it in the radial direction of 0° while rotating the belt. After that, a cutter blade is inserted into the elastic layer / base layer interface, and the blade is advanced horizontally to the interface to peel off the base layer. The thermal conductivity of the obtained elastic layer is measured under a load of 50 g by thermal wave analysis using ai-phase (manufactured by ai-phase Co., Ltd.).

[0055] (Young's Modulus) From the viewpoint of shape conformability, the Young's modulus of the elastic layer (1) is preferably 0.2 MPa or more and 1.0 MPa or less, more preferably 0.2 MPa or more and 0.6 MPa or less, and even more preferably 0.2 MPa or more and 0.4 MPa or less.

[0056] The Young's modulus of the elastic layer is measured as follows. First, the resin substrate layer and the release layer are peeled off from the fixing belt in the same manner as in the measurement of thermal conductivity. The obtained elastic layer of the subject is measured with Rheovibron (manufactured by Orientec Co., Ltd.) at an amplitude of 50 μm and a frequency of 10 Hz, and the value at 150° C. is used.

[0057] [Formation of elastic layer (1)] The elastic layer (1) may be formed by a known method, for example, a coating method. When silicone rubber is used as the elastic material of the elastic layer, for example, first prepare a coating liquid for forming an elastic layer, which contains a liquid silicone rubber that is cured by heating to become silicone rubber. Next, the coating liquid for forming an elastic layer is applied onto the base layer to form a coating film, and the coating film is vulcanized as necessary to form an elastic layer on the base layer. In addition, in the vulcanization of the coating film, the vulcanization temperature can be, for example, 150°C or more and 250°C or less, and the vulcanization time can be, for example, 30 minutes or more and 120 minutes or less.

[0058] When preparing the coating liquid for forming the elastic layer, it is preferable to simultaneously produce a specific assembly. Specifically, one example of such a method includes preparing a precursor liquid containing an elastic material and fibrous carbon (also referred to as a precursor liquid preparation process), producing a specific aggregate in the precursor liquid system (also referred to as a specific aggregate production process), and obtaining a coating liquid containing the elastic material and the specific aggregate. The precursor liquid preparation step and the specific assembly manufacturing step will be described below.

[0059] (Precursor liquid preparation process) In the precursor liquid preparation step, it is preferable to first mix the fibrous carbon with a dispersion medium to prepare a dispersion liquid in which the fibrous carbon is dispersed. Here, the dispersion medium may be an organic solvent in which the fibrous carbon does not dissolve or is difficult to dissolve, but which the elastic material can dissolve in. For example, when silicone rubber is used as the elastic material, the dispersion medium may be butyl acetate, toluene, heptane, benzene, acetone, or the like. Here, the content of the fibrous carbon in the dispersion liquid is preferably 10 mass % or more and 40 mass % or less (more preferably 15 mass % or more and 30 mass % or less) based on the total mass of the dispersion liquid.

[0060] The obtained dispersion liquid is preferably subjected to a high-pressure dispersion treatment. By performing the high-pressure dispersion treatment, the fibrous carbon in the dispersion liquid is loosened and individually isolated, and further, the length of the fibrous carbon in the dispersion liquid is adjusted. Here, the conditions of the high pressure dispersion treatment may be any conditions that allow the fibrous carbon to be individually isolated and the length of the fibrous carbon to be adjusted to a desired value. For example, the high pressure dispersion treatment is preferably performed under a liquid temperature of the dispersion liquid of 30°C or more and 60°C or less, and a pressure of 20MPa or more and 100MPa or less (preferably, 40MPa or more and 80MPa or less). For the high pressure dispersion treatment, for example, a high pressure homogenizer is used.

[0061] The length of the fibrous carbon in the dispersion liquid is preferably adjusted to about 0.5 μm or more and 100 μm or less (preferably, 2 μm or more and 80 μm or less). Here, the length of the fibrous carbon in the dispersion liquid can be measured by observation with an optical microscope or an electron microscope. The maximum diameter of a specific aggregate can be controlled by the length of the fibrous carbon in the dispersion liquid. Specifically, there is a tendency that the longer the fibrous carbon, the larger the maximum diameter of the aggregate that can be produced.

[0062] In the precursor liquid preparation step, an elastic material is subsequently added to the dispersion liquid obtained as described above to prepare a precursor liquid. The amount of the elastic material added is preferably about 10% by mass or more and 90% by mass or less (more preferably 15% by mass or more and 60% by mass or less) in terms of solid content concentration relative to the total mass of the precursor liquid.

[0063] (Specific aggregate manufacturing process) In the specific assembly production step, the precursor liquid obtained in the precursor liquid preparation step is stirred by a planetary mixer, and the specific assembly is produced in the system. By stirring the precursor liquid with a planetary mixer, the fibrous carbon that was individually isolated in the precursor liquid gradually becomes entangled and lumps, producing a specific aggregate.

[0064] Here, the stirring conditions using the planetary mixer may be any conditions under which specific aggregates having the desired maximum diameter can be obtained. For example, the stirring conditions are preferably such that the temperature of the precursor liquid is 25° C. or more and 40° C. or less, and the stirring is performed under vacuum for 10 minutes or more and 60 minutes or less. The maximum diameter of a particular aggregate can be controlled by the stirring conditions. Specifically, the longer the stirring time using a planetary mixer, the larger the maximum diameter of the aggregates that can be produced tends to be.

[0065] In the specific aggregate manufacturing process, all of the fibrous carbon contained in the precursor liquid may become specific aggregates, or some fibrous carbon that does not form specific aggregates (i.e., fibrous carbon that is not entangled with each other) may remain together with the specific aggregates.

[0066] In this manner, a mixed liquid containing the elastic material and the specific aggregate is obtained. To the obtained mixture, other components (unentangled fibrous carbon, additives, etc.) are added as necessary to obtain a coating liquid for forming an elastic layer. The obtained mixture may be diluted with an organic solvent to adjust the viscosity of the coating liquid.

[0067] [Elastic layer (2)] The elastic layer in the second embodiment of the fixing belt according to the present disclosure (i.e., elastic layer (2)) contains an elastic material and fibrous carbon, and has a thermal conductivity of 1.0 W / m·K or more and 4.5 W / m·K or less, and a Young's modulus of 0.2 MPa or more and 1.0 MPa or less.

[0068] From the viewpoint of suppressing offset, the elastic layer (2) preferably has a thermal conductivity of 1.0 W / m·K or more and 4.5 W / m·K or less and a Young's modulus of 0.2 MPa or more and 1.0 MPa or less, and more preferably has a thermal conductivity of 2.0 W / m·K or more and 4.5 W / m·K or less and a Young's modulus of 0.2 MPa or more and 0.6 MPa or less.

[0069] The elastic layer (2), like the above-described elastic layer (1), preferably contains an elastic material and a specific aggregate as fibrous carbon, and more preferably contains a resin, the specific aggregate, and unentangled fibrous carbon. The preferred aspects of the resin, the specific aggregates, and the non-entangled fibrous carbon contained in the elastic layer (2) are the same as those of the resin, the specific aggregates, and the non-entangled fibrous carbon contained in the elastic layer (1). The contents of the resin, the specific aggregates, and the non-entangled fibrous carbon are preferably the same as those of the resin, the specific aggregates, and the non-entangled fibrous carbon contained in the elastic layer (1). Similarly to the above-mentioned elastic layer (1), the elastic layer (2) may contain additives. Furthermore, the thickness of the elastic layer (2) is the same as that of the above-mentioned elastic layer (1). In addition, the elastic layer (2) can be formed in the same manner as the elastic layer (1) described above.

[0070] [Resin base material layer] In the fixing belt according to the present disclosure, the resin substrate layer is a layer containing a resin. The resin content in the resin substrate layer is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, particularly preferably 80% by mass or more, and most preferably 90% by mass or more, based on the total mass of the resin substrate layer.

[0071] [resin] The resin contained in the resin substrate layer is preferably a heat-resistant resin. Examples of the resin include heat-resistant resins having high heat resistance and high strength, such as polyimide, aromatic polyamide, and liquid crystal materials such as thermotropic liquid crystal polymer. In addition to these, polyester, polyethylene terephthalate, polyethersulfone, polyether ketone, polysulfone, polyimide amide, etc. may be used. Among these, polyimide is preferred as the resin.

[0072] Examples of polyimides include imidized products of polyamic acids (precursors of polyimide resins), which are polymers of tetracarboxylic dianhydrides and diamine compounds.Specific examples of polyimides include resins obtained by polymerizing equimolar amounts of tetracarboxylic dianhydrides and diamine compounds in a solvent to obtain a polyamic acid solution, and then imidizing the polyamic acid.

[0073] The tetracarboxylic dianhydride may be either an aromatic or aliphatic compound, but from the viewpoint of heat resistance, an aromatic compound is preferred.

[0074] Examples of aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenylsulfone tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3',4,4'-biphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3',4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furan tetracarboxylic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride, 4,4 Examples of the dianhydride include 3,3',4,4'-bis(3,4-dicarboxyphenoxy)diphenylsulfone dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, 3,3',4,4'-perfluoroisopropylidenediphthalic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, bis(phthalic acid)phenylphosphine oxide dianhydride, p-phenylene-bis(triphenylphthalic acid) dianhydride, m-phenylene-bis(triphenylphthalic acid) dianhydride, bis(triphenylphthalic acid)-4,4'-diphenyl ether dianhydride, and bis(triphenylphthalic acid)-4,4'-diphenylmethane dianhydride.

[0075] Examples of the aliphatic tetracarboxylic dianhydride include butane tetracarboxylic dianhydride, 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentane tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic dianhydride, 3,5,6-tricarboxynorbonane-2-acetic dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, bicyclo[2,2,2]-oct-7-ene aliphatic or alicyclic tetracarboxylic acid dianhydrides such as 1,3,3a,4,5,9b-hexahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-5-methyl-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione, and 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione.

[0076] Among these, the tetracarboxylic acid dianhydride is preferably an aromatic tetracarboxylic acid dianhydride, specifically, for example, pyromellitic acid dianhydride, 3,3',4,4'-biphenyl tetracarboxylic acid dianhydride, 2,3,3',4'-biphenyl tetracarboxylic acid dianhydride, 3,3',4,4'-biphenyl ether tetracarboxylic acid dianhydride, 3,3',4,4'-benzophenone tetracarboxylic acid dianhydride, further, pyromellitic acid dianhydride, 3,3',4,4'-biphenyl tetracarboxylic acid dianhydride, 3,3',4,4'-benzophenone tetracarboxylic acid dianhydride is more preferable, and 3,3',4,4'-biphenyl tetracarboxylic acid dianhydride is particularly preferable.

[0077] The tetracarboxylic dianhydrides may be used alone or in combination of two or more. In addition, when two or more kinds of tetracarboxylic dianhydrides are used in combination, aromatic tetracarboxylic dianhydrides or aliphatic tetracarboxylic dianhydrides may be used in combination, or an aromatic tetracarboxylic dianhydride and an aliphatic tetracarboxylic dianhydride may be used in combination.

[0078] On the other hand, the diamine compound is a diamine compound having two amino groups in the molecular structure. The diamine compound may be either an aromatic or aliphatic compound, but is preferably an aromatic compound.

[0079] Examples of the diamine compound include p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4'-diaminodiphenylether, 4,4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 1,5-diaminonaphthalene, 3,3-dimethyl-4,4'-diaminobiphenyl, 5-amino-1-(4'-aminophenyl)-1,3,3-trimethylindane, 6-amino-1-(4'-aminophenyl)-1,3 ,3-Trimethylindane, 4,4'-diaminobenzanilide, 3,5-diamino-3'-trifluoromethylbenzanilide, 3,5-diamino-4'-trifluoromethylbenzanilide, 3,4'-diaminodiphenyl ether, 2,7-diaminofluorene, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-methylene-bis(2-chloroaniline), 2,2',5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diamino-5,5'-diamine Toxobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)-biphenyl, 1,3'-bis(4-aminophenoxy)benzene, 9,9-bis(4-aminophenyl)fluorene aromatic diamines such as 4,4'-(p-phenyleneisopropylidene)bisaniline, 4,4'-(m-phenyleneisopropylidene)bisaniline, 2,2'-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]hexafluoropropane, and 4,4'-bis[4-(4-amino-2-trifluoromethyl)phenoxy]-octafluorobiphenyl; aromatic diamines having two amino groups bonded to an aromatic ring and a heteroatom other than the nitrogen atom of the amino group, such as diaminotetraphenylthiophene;1,1-meta-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, octamethylenediamine, nonamethylenediamine, 4,4-diaminoheptamethylenediamine, 1,4-diaminocyclohexane, isophoronediamine, tetrahydrodicyclopentadienylenediamine, hexahydro-4,7-methanoindanidinediamine, tricyclo[6,2,1,0; 2.7 ]-undecylenedimethyldiamine, 4,4'-methylenebis(cyclohexylamine), and other aliphatic diamines and alicyclic diamines.

[0080] Among these, the diamine compound is preferably an aromatic diamine compound, specifically, for example, p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, and particularly, 4,4'-diaminodiphenyl ether and p-phenylenediamine are preferable.

[0081] The diamine compounds may be used alone or in combination of two or more. When two or more diamine compounds are used in combination, aromatic diamine compounds or aliphatic diamine compounds may be used in combination, or an aromatic diamine compound and an aliphatic diamine compound may be used in combination.

[0082] Among these, from the viewpoint of heat resistance, aromatic polyimides (specifically, imidized products of polyamic acids (precursors of polyimide resins), which are polymers of aromatic tetracarboxylic dianhydrides and aromatic diamine compounds) are preferred as polyimides. The aromatic polyimide is more preferably a polyimide having a structural unit represented by the following general formula (PI1).

[0083] [ka]

[0084] In the general formula (PI1), R P1 represents a phenyl group or a biphenyl group, and R P2 represents a divalent aromatic group. R P2 Examples of the divalent aromatic group represented by the formula (I) include a phenylene group, a naphthyl group, a biphenyl group, a diphenyl ether group, etc. As the divalent aromatic group, a phenylene group and a biphenyl group are preferred from the viewpoint of flexural durability.

[0085] The number average molecular weight of the polyimide is preferably 5,000 or more and 100,000 or less, more preferably 7,000 or more and 50,000 or less, and further preferably 10,000 or more and 30,000 or less.

[0086] The number average molecular weight of polyimide is measured by gel permeation chromatography (GPC) under the following measurement conditions. Column: Tosoh TSKgel α-M (7.8 mm ID x 30 cm) Eluent: DMF (dimethylformamide) / 30mM LiBr / 60mM phosphoric acid ·Flow rate: 0.6mL / min ·Injection volume: 60μL Detector: RI (Differential Refractive Index Detector)

[0087] From the viewpoints of thermal conductivity and mechanical strength, the resin substrate layer has a thickness of preferably 30 μm to 200 μm, more preferably 50 μm to 150 μm, and particularly preferably 70 μm to 120 μm.

[0088] [Formation of resin substrate layer] The resin substrate layer is obtained by preparing a substrate layer forming coating liquid containing a resin and an additive used as necessary, applying the obtained substrate layer forming coating liquid onto a cylindrical substrate, and drying it. When the resin is polyimide, the substrate layer forming coating liquid is prepared containing a polyamic acid (a precursor of polyimide resin) and an additive used as necessary, applying the obtained substrate layer forming coating liquid onto a cylindrical substrate, and baking (i.e., imidization).

[0089] (Release layer) The fixing belt according to the present disclosure has a release layer on the elastic layer. The release layer is a layer that plays a role in preventing the molten toner image from sticking to the surface (outer peripheral surface) that comes into contact with a recording medium during fixing.

[0090] The release layer is required to have, for example, heat resistance and releasability. From this viewpoint, it is preferable to use a heat-resistant release material as the material constituting the release layer, and specific examples thereof include fluororubber, fluororesin, silicone resin, polyimide resin, and the like. Among these, fluororesin is preferable as the heat-resistant release material. Specific examples of fluororesins include tetrafluoroethylene-perfluoroalkylvinyl ether copolymer (PFA), polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polyethylene-tetrafluoroethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), and vinyl fluoride (PVF).

[0091] The surface of the release layer on the elastic layer side may be subjected to a surface treatment. The surface treatment may be a wet treatment or a dry treatment, and examples of the surface treatment include a liquid ammonia treatment, an excimer laser treatment, and a plasma treatment.

[0092] The thickness of the release layer is preferably 10 μm or more and 100 μm or less, and more preferably 20 μm or more and 50 μm or less.

[0093] The release layer may be formed by a known method, for example, a coating method. Alternatively, a tubular release layer may be prepared in advance and coated on the outer periphery of the elastic layer to form the release layer. Note that an adhesive layer (e.g., an adhesive layer containing a silane coupling agent having an epoxy group) may be formed on the inner surface of the tubular release layer, and then the outer periphery may be coated.

[0094] The thickness of the fixing belt according to the present disclosure is, for example, preferably 0.06 mm or more and 0.90 mm or less, more preferably 0.15 mm or more and 0.70 mm or less, and even more preferably 0.10 mm or more and 0.60 mm or less.

[0095] [Use of fixing belt member] The fixing belt according to the present disclosure is applicable to, for example, either a heating belt or a pressure belt. Note that the heating belt may be either a heating belt that is heated by electromagnetic induction or a heating belt that is heated from an external heat source. However, when the fixing belt according to the present disclosure is applied to a heating belt that heats by electromagnetic induction, it is preferable to provide a metal layer (heat-generating layer) that generates heat by electromagnetic induction between the base layer and the elastic layer.

[0096] <Fixing device> The fixing device according to the present disclosure has various configurations, and an example thereof is a fixing device that includes a first rotating body and a second rotating body arranged in contact with the outer surface of the first rotating body, and fixes the toner image by inserting a recording medium having a toner image formed on its surface into a contact portion between the first rotating body and the second rotating body. The fixing belt according to the present disclosure is applied as at least one of the first rotating body and the second rotating body.

[0097] The fixing device according to the present disclosure will be described below in the following three embodiments: a fixing device including a heating roll and a pressure belt as a first embodiment, a fixing device including a heating belt and a heating roll as a second embodiment, and an electromagnetic induction heating type fixing device including a heating belt and a heating roll as a third embodiment. In the first and second embodiments, the fixing belt according to the present disclosure can be applied to either the heating belt or the pressure belt. The fixing device according to the present disclosure is not limited to the first to third embodiments, and may be a fixing device including a heating roll or a heating belt and a pressure belt. The fixing belt according to the present disclosure may be applied to both the heating belt and the pressure belt.

[0098] (First embodiment of fixing device) A first embodiment of the fixing device will be described with reference to Fig. 2. Fig. 2 is a schematic diagram showing an example of the first embodiment of the fixing device (that is, fixing device 60).

[0099] As shown in FIG. 2, the fixing device 60 is configured to include, for example, a rotating heating roll 61 (an example of a first rotating body), a pressure belt 62 (an example of a second rotating body), and a pressure pad 64 (an example of a pressing member) that presses the heating roll 61 via the pressure belt 62. The pressing pad 64 may be configured to press the pressure belt 62 and the heating roll 61 relatively. Therefore, the pressure belt 62 side may be pressed against the heating roll 61, or the heating roll 61 side may be pressed against the heating roll 61.

[0100] A halogen lamp 66 (an example of a heating means) is disposed inside the heating roll 61. The heating means is not limited to a halogen lamp, and other heat generating members may be used.

[0101] On the other hand, for example, a temperature sensor 69 is arranged in contact with the surface of the heating roll 61. Based on the temperature measurement value by this temperature sensor 69, the lighting of the halogen lamp 66 is controlled, and the surface temperature of the heating roll 61 is maintained at a target set temperature (for example, 150°C).

[0102] The pressure belt 62 is rotatably supported by, for example, a pressure pad 64 and a belt running guide 63 disposed inside the pressure belt 62. The pressure belt 62 is disposed so as to be pressed against the heating roll 61 by the pressure pad 64 in a sandwiching region N (nip portion).

[0103] The pressure pad 64 is disposed, for example, inside the pressure belt 62 in a state where it is pressed by the heating roll 61 via the pressure belt 62, and forms a sandwiching region N between the pressure pad 64 and the heating roll 61. The pressure pad 64, for example, has a front clamping member 64a arranged on the entrance side of the clamping area N to ensure a wide clamping area N, and a peeling clamping member 64b arranged on the exit side of the clamping area N to impart distortion to the heating roll 61.

[0104] In order to reduce the sliding resistance between the inner circumferential surface of the pressure belt 62 and the pressure pad 64, for example, a sheet-like sliding member 68 is provided on the surfaces of the front clamping member 64a and the peeling clamping member 64b that come into contact with the pressure belt 62. The pressure pad 64 and the sliding member 68 are held by a holding member 65 made of metal. The sliding member 68 is provided, for example, so that its sliding surface comes into contact with the inner circumferential surface of the pressure belt 62 , and is involved in the retention and supply of oil present between the sliding member 68 and the pressure belt 62 .

[0105] For example, a belt running guide 63 is attached to the holding member 65, and the pressure belt 62 rotates.

[0106] The heating roll 61 is rotated in the direction of arrow S by, for example, a drive motor (not shown), and the pressure belt 62 is driven by this rotation to rotate in the direction of arrow R, which is opposite to the rotation direction of the heating roll 61. That is, for example, while the heating roll 61 rotates in the clockwise direction in FIG. 2, the pressure belt 62 rotates in the counterclockwise direction.

[0107] Then, the paper K (an example of a recording medium) having the unfixed toner image thereon is guided, for example, by the fixing entrance guide 56 and conveyed to the pinch region N. Then, when the paper K passes through the pinch region N, the unfixed toner image on the paper K is fixed by the pressure and heat acting on the pinch region N.

[0108] In the fixing device 60, for example, the front pinch member 64a having a concave shape conforming to the outer circumferential surface of the heating roll 61 ensures a wider pinch region N than in a configuration without the front pinch member 64a.

[0109] In addition, in the fixing device 60, for example, by arranging the peeling and pinching member 64b so as to protrude from the outer circumferential surface of the heating roll 61, the distortion of the heating roll 61 is locally increased in the exit area of ​​the pinching region N.

[0110] By arranging the peeling and pinching member 64b in this manner, for example, when the paper K after fixing passes through the peeling and pinching area, it passes through a locally large distortion, making it easier for the paper K to peel off from the heating roll 61.

[0111] As an auxiliary means for peeling, for example, a peeling member 70 is disposed downstream of the pinching region N of the heating roll 61. The peeling member 70 is held by a holding member 72 in a state in which a peeling claw 71 is adjacent to the heating roll 61 in a direction opposite to the rotation direction of the heating roll 61 (counter direction), for example.

[0112] (Second embodiment of fixing device) A second embodiment of the fixing device will be described with reference to Fig. 3. Fig. 3 is a schematic diagram showing an example of the second embodiment of the fixing device (that is, fixing device 80).

[0113] 3, the fixing device 80 includes, for example, a fixing belt module 86 equipped with a heating belt 84 (an example of a first rotating body), and a pressure roll 88 (an example of a second rotating body) arranged to press against the heating belt 84 (fixing belt module 86). For example, a pinch region N (nip portion) is formed at the contact portion between the heating belt 84 (fixing belt module 86) and the pressure roll 88. In the pinch region N, a sheet K (an example of a recording medium) is pressurized and heated, and a toner image is fixed.

[0114] The fixing belt module 86 includes, for example, an endless heating belt 84, a heating pressure roll 89 around which the heating belt 84 is wound on the pressure roll 88 side and which is rotated by the rotational force of a motor (not shown) and presses the heating belt 84 from its inner surface against the pressure roll 88 side, and a support roll 90 which supports the heating belt 84 from the inside at a position different from the heating pressure roll 89. The fixing belt module 86 includes, for example, a support roll 92 arranged on the outside of the heating belt 84 to define its rotational path, a posture correction roll 94 to correct the posture of the heating belt 84 from the heating pressure roll 89 to the support roll 90, and a support roll 98 to apply tension to the heating belt 84 from its inner surface downstream of the clamping area N formed by the heating belt 84 and the pressure roll 88.

[0115] The fixing belt module 86 is provided, for example, between the heating belt 84 and the heating pressure roll 89 so that a sheet-like sliding member 82 is interposed. The sliding member 82 is provided, for example, so that its sliding surface comes into contact with the inner circumferential surface of the heating belt 84 , and is involved in the retention and supply of oil present between the sliding member 82 and the heating belt 84 . Here, the sliding member 82 is provided in a state in which both ends thereof are supported by supporting members 96, for example.

[0116] Inside the heating and pressing roll 89, for example, a halogen heater 89A (one example of a heating means) is provided.

[0117] The support roll 90 is, for example, a cylindrical roll made of aluminum, and has a halogen heater 90A (an example of a heating means) disposed therein, so as to heat the heating belt 84 from the inner circumferential surface side. At both ends of the support roll 90, for example, spring members (not shown) are provided to press the heating belt 84 outward.

[0118] The support roll 92 is a cylindrical roll made of, for example, aluminum, and a release layer made of fluororesin having a thickness of 20 μm is formed on the surface of the support roll 92. The release layer of the support roll 92 is formed, for example, to prevent toner and paper powder from the outer circumferential surface of the heating belt 84 from accumulating on the support roll 92 . Inside the support roll 92, for example, a halogen heater 92A (one example of a heating means) is disposed, and the heating belt 84 is heated from the outer circumferential surface side.

[0119] That is, for example, the heating belt 84 is heated by a heating pressure roll 89 and a supporting roll 90 and a supporting roll 92 .

[0120] The posture correction roll 94 is, for example, a cylindrical roll made of aluminum, and an end position measuring mechanism (not shown) that measures the end position of the heating belt 84 is disposed near the posture correction roll 94. The posture correction roll 94 is provided with, for example, an axial displacement mechanism (not shown) that displaces the contact position in the axial direction of the heating belt 84 in accordance with the measurement results of the end position measuring mechanism, and is configured to control the meandering of the heating belt 84.

[0121] On the other hand, the pressure roll 88 is, for example, supported rotatably and is provided so as to be pressed against the portion where the heating belt 84 is wound around the heating pressure roll 89 by a biasing means such as a spring (not shown). As a result, as the heating belt 84 (heating pressure roll 89) of the fixing belt module 86 rotates in the direction of arrow S, the pressure roll 88 rotates in the direction of arrow R, following the heating belt 84 (heating pressure roll 89).

[0122] Then, the paper K having an unfixed toner image (not shown) is transported in the direction of arrow P and guided to a pinch area N of the fixing device 80. Then, when the paper K passes through the pinch area N, the unfixed toner image on the paper K is fixed by pressure and heat acting on the pinch area N.

[0123] In the fixing device 80, a form in which a halogen heater (halogen lamp) is applied as an example of multiple heating means has been described, but this is not limited to this, and a radiant lamp heating element (a heating element that emits radiation (infrared rays, etc.)) other than a halogen heater, or a resistive heating element (a heating element that generates Joule heat by passing an electric current through a resistor: for example, a film having resistance formed on a ceramic substrate and then fired) may also be applied.

[0124] (Third embodiment of fixing device) A fixing device according to a third embodiment will be described with reference to Fig. 4. Fig. 4 is a schematic diagram showing an example of the fixing device according to the third embodiment (that is, fixing device 200).

[0125] The fixing device 200 is an electromagnetic induction type fixing device including a belt 220 having a metal layer. In the fixing device 200, the belt 220 is used as the fixing belt according to the present disclosure. 4, a pressure roll (pressure member) 211 is disposed so as to pressurize a portion of the belt 220, and from the viewpoint of efficient fixing, a contact area (nip) is formed between the belt 220 and the pressure roll 211, and the belt 220 is curved to conform to the circumferential surface of the pressure roll 211. Also, from the viewpoint of ensuring the peelability of the recording medium, a bent portion is formed at the end of the contact area (nip) where the belt is bent.

[0126] The pressure roll 211 is configured such that an elastic layer 211B made of silicone rubber or the like is formed on a base material 211A, and a release layer 211C made of a fluorine-based compound is further formed on the elastic layer 211B.

[0127] An opposing member 213 is disposed on the inner side of the belt 220 at a position opposing the pressure roll 211. The opposing member 213 is made of metal, heat-resistant resin, heat-resistant rubber, or the like, and has a pad 213B that comes into contact with the inner circumferential surface of the belt 220 to locally increase pressure, and a support 13A that supports the pad 213B.

[0128] An electromagnetic induction heating device 212 incorporating an electromagnetic induction coil (excitation coil) 212a is provided at a position facing the pressure roll 211 (an example of a pressure member) with the belt 220 at the center. The electromagnetic induction heating device 212 applies an alternating current to the electromagnetic induction coil, thereby changing the generated magnetic field with an excitation circuit and generating an eddy current in a metal layer (not shown) of the belt 220 (for example, an electromagnetic induction metal layer). This eddy current is converted into heat (Joule heat) by the electrical resistance of the metal layer (not shown), and as a result, the surface of the belt 220 generates heat. The position of the electromagnetic induction heating device 212 is not limited to the position shown in FIG. 4, and may be installed, for example, on the upstream side of the contact area of ​​the belt 220 in the rotation direction B, or may be installed on the inside of the belt 220.

[0129] In the fixing device 200, a driving force is transmitted from a driving device to a gear fixed to the end of the belt 220, causing the belt 220 to rotate by itself in the direction of arrow B, and as the belt 220 rotates, the pressure roll 211 rotates in the opposite direction, i.e., in the direction of arrow C. The recording medium 215 on which the unfixed toner image 214 is formed is passed through a contact area (nip) between the belt 220 and the pressure roll 211 in the fixing device 200 in the direction of arrow A, and the unfixed toner image 214 is fixed to the recording medium 215 by applying pressure to the molten toner image 214.

[0130] <Image forming device> Next, an image forming apparatus according to the present disclosure will be described. The image forming apparatus according to the present disclosure includes an image carrier, a charging means for charging the surface of the image carrier, an electrostatic latent image forming means for forming an electrostatic latent image on the surface of the charged image carrier, a developing means for developing the electrostatic latent image formed on the surface of the image carrier with a developer containing toner to form a toner image, a transfer means for transferring the toner image to the surface of a recording medium, and a fixing means for fixing the toner image to the recording medium. As the fixing means, the fixing device according to the present disclosure is applied.

[0131] Here, in the image forming apparatus according to the present disclosure, the fixing device may be formed as a cartridge so as to be detachably attached to the image forming apparatus, i.e., the image forming apparatus according to the present disclosure may include the fixing device according to the present disclosure as a component device of a process cartridge.

[0132] Hereinafter, an image forming apparatus according to the present disclosure will be described with reference to the drawings. FIG. 5 is a schematic diagram showing the configuration of an image forming apparatus according to the present disclosure.

[0133] 5, the image forming apparatus 100 according to the present disclosure is, for example, an intermediate transfer type image forming apparatus generally called a tandem type, and includes a plurality of image forming units 1Y, 1M, 1C, and 1K in which toner images of each color component are formed by an electrophotographic method, a primary transfer section 10 that sequentially transfers (primary transfer) the toner images of each color component formed by each image forming unit 1Y, 1M, 1C, and 1K onto an intermediate transfer belt 15, a secondary transfer section 20 that collectively transfers (secondary transfer) the superimposed toner images transferred onto the intermediate transfer belt 15 onto a recording medium, paper K, and a fixing device 60 that fixes the secondarily transferred image onto the paper K. The image forming apparatus 100 also has a control section 40 that controls the operation of each device (each section).

[0134] The fixing device 60 is the first embodiment of the fixing device described above. Note that the image forming apparatus 100 may be configured to include the second embodiment of the fixing device described above.

[0135] Each of the image forming units 1Y, 1M, 1C, and 1K of the image forming apparatus 100 includes a photoconductor 11 that rotates in the direction of arrow A as an example of an image carrier that carries a toner image formed on its surface.

[0136] Around the photoconductor 11, there is provided a charger 12 as an example of a charging means for charging the photoconductor 11, and there is provided a laser exposure device 13 (the exposure beam is indicated by the symbol Bm in the figure) as an example of a latent image forming means for writing an electrostatic latent image on the photoconductor 11.

[0137] In addition, around the photoconductor 11, there is provided a developing device 14 as an example of a developing means, which contains each color component toner and makes the electrostatic latent image on the photoconductor 11 visible using the toner, and there is provided a primary transfer roll 16 which transfers each color component toner image formed on the photoconductor 11 to an intermediate transfer belt 15 at the primary transfer section 10.

[0138] Furthermore, a photoreceptor cleaner 17 that removes residual toner on the photoreceptor 11 is provided around the photoreceptor 11, and electrophotographic devices including a charger 12, a laser exposure device 13, a developer 14, a primary transfer roll 16, and the photoreceptor cleaner 17 are sequentially arranged along the rotation direction of the photoreceptor 11. These image forming units 1Y, 1M, 1C, and 1K are arranged in a substantially linear fashion in the order of yellow (Y), magenta (M), cyan (C), and black (K) from the upstream side of the intermediate transfer belt 15.

[0139] The intermediate transfer belt 15, which is an intermediate transfer body, is a film-like pressure belt that has a base layer of resin such as polyimide or polyamide and contains an appropriate amount of antistatic agent such as carbon black. 6 Ωcm or more 10 14 It is formed to have a resistivity of Ωcm or less, and its thickness is, for example, about 0.1 mm.

[0140] The intermediate transfer belt 15 is driven (rotated) in a circular manner by various rolls at a speed suited to the purpose in the direction B shown in Fig. 5. The various rolls include a drive roll 31 driven by a motor (not shown) excellent in constant speed performance to rotate the intermediate transfer belt 15, a support roll 32 supporting the intermediate transfer belt 15 extending in a substantially straight line along the arrangement direction of the photoconductors 11, a tensioning roll 33 that applies tension to the intermediate transfer belt 15 and functions as a correction roll to prevent the intermediate transfer belt 15 from meandering, a back roll 25 provided in the secondary transfer unit 20, and a cleaning back roll 34 provided in a cleaning unit that scrapes off residual toner on the intermediate transfer belt 15.

[0141] The primary transfer section 10 is composed of a primary transfer roll 16 arranged opposite the photoconductor 11 with an intermediate transfer belt 15 sandwiched therebetween. The primary transfer roll 16 is composed of a core body and a sponge layer as an elastic layer fixed to the periphery of the core body. The core body is a cylindrical rod made of a metal such as iron or SUS. The sponge layer is formed of a blend rubber of NBR, SBR and EPDM mixed with a conductive agent such as carbon black, and has a volume resistivity of 10 7.5Ωcm or more 10 8.5 It is a sponge-like cylindrical roll with a surface resistance of less than Ωcm.

[0142] The primary transfer roll 16 is arranged in pressure contact with the photoconductor 11 with the intermediate transfer belt 15 sandwiched therebetween, and furthermore, a voltage (primary transfer bias) of the opposite polarity to the charge polarity of the toner (negative polarity; the same applies below) is applied to the primary transfer roll 16. As a result, the toner images on the photoconductors 11 are electrostatically attracted to the intermediate transfer belt 15 in sequence, and superimposed toner images are formed on the intermediate transfer belt 15.

[0143] The secondary transfer unit 20 includes a back roll 25 and a secondary transfer roll 22 that is disposed on the toner image bearing surface side of the intermediate transfer belt 15 .

[0144] The back roll 25 is made of a tube of EPDM and NBR blend rubber with carbon dispersed on the surface, and the inside is made of EPDM rubber. 7 Ω / □ or more 10 10 The hardness is set to, for example, 70° (Asker C: manufactured by Kobunshi Keiki Co., Ltd., the same applies below.) The back roll 25 is disposed on the back side of the intermediate transfer belt 15 to constitute an opposing electrode of the secondary transfer roll 22, and is in contact with a metallic power supply roll 26 to which a secondary transfer bias is stably applied.

[0145] On the other hand, the secondary transfer roll 22 is composed of a core body and a sponge layer as an elastic layer fixed around the core body. The core body is a cylindrical rod made of a metal such as iron or SUS. The sponge layer is made of a blend rubber of NBR, SBR and EPDM mixed with a conductive agent such as carbon black, and has a volume resistivity of 10 7.5 Ωcm or more 10 8.5 It is a sponge-like cylindrical roll with a surface resistance of less than Ωcm.

[0146] The secondary transfer roll 22 is placed in pressure contact with the back roll 25 with the intermediate transfer belt 15 sandwiched therebetween, and further, the secondary transfer roll 22 is grounded to form a secondary transfer bias between the secondary transfer roll 22 and the back roll 25, thereby secondarily transferring the toner image onto the paper K transported to the secondary transfer section 20.

[0147] In addition, downstream of the secondary transfer section 20 of the intermediate transfer belt 15, an intermediate transfer belt cleaner 35 that removes residual toner and paper dust on the intermediate transfer belt 15 after the secondary transfer and cleans the surface of the intermediate transfer belt 15 is provided so as to be freely movable toward and away from the intermediate transfer belt 15.

[0148] The intermediate transfer belt 15, the primary transfer section 10 (the primary transfer roll 16), and the secondary transfer section 20 (the secondary transfer roll 22) correspond to an example of a transfer unit.

[0149] Meanwhile, upstream of the yellow image forming unit 1Y, there is provided a reference sensor (home position sensor) 42 that generates a reference signal that serves as a reference for timing image formation in each of the image forming units 1Y, 1M, 1C, and 1K. This reference sensor 42 generates a reference signal by recognizing a mark provided on the back side of the intermediate transfer belt 15, and each of the image forming units 1Y, 1M, 1C, and 1K is configured to start image formation in response to an instruction from the control unit 40 based on the recognition of this reference signal. Further, an image density sensor 43 for adjusting image quality is disposed downstream of the black image forming unit 1K.

[0150] Furthermore, in the image forming apparatus according to the present disclosure, as a transport means for transporting the paper K, there are provided a paper storage section 50 for storing the paper K, a paper feed roll 51 for taking out and transporting the paper K accumulated in the paper storage section 50 at a predetermined timing, a transport roll 52 for transporting the paper K unwound by the paper feed roll 51, a transport guide 53 for sending the paper K transported by the transport roll 52 to the secondary transfer section 20, a transport belt 55 for transporting the paper K transported after secondary transfer by the secondary transfer roll 22 to the fixing device 60, and a fixing entrance guide 56 for guiding the paper K to the fixing device 60.

[0151] Next, a basic image forming process of the image forming apparatus according to the present disclosure will be described. In the image forming apparatus of the present disclosure, image data output from an image reading device (not shown) or a personal computer (PC) (not shown), etc., is subjected to image processing by an image processing device (not shown), and then image formation is performed by image forming units 1Y, 1M, 1C, and 1K.

[0152] The image processing device performs image processing on the input reflectance data, such as shading correction, positional deviation correction, brightness / color space conversion, gamma correction, and various image editing such as frame erasure, color editing, and movement editing. The image data that has undergone image processing is converted into color material gradation data of four colors, Y, M, C, and K, and is output to the laser exposure device 13.

[0153] In the laser exposure device 13, an exposure beam Bm emitted from, for example, a semiconductor laser is irradiated onto the photoconductor 11 of each of the image forming units 1Y, 1M, 1C, and 1K in accordance with the input color material gradation data. In each of the photoconductors 11 of the image forming units 1Y, 1M, 1C, and 1K, the surface is charged by the charger 12, and then the surface is scanned and exposed by the laser exposure device 13 to form an electrostatic latent image. The formed electrostatic latent image is developed into a toner image of each color of Y, M, C, and K by each of the image forming units 1Y, 1M, 1C, and 1K.

[0154] The toner images formed on the photoconductors 11 of the image forming units 1Y, 1M, 1C, and 1K are transferred onto the intermediate transfer belt 15 in the primary transfer section 10 where each photoconductor 11 comes into contact with the intermediate transfer belt 15. More specifically, in the primary transfer section 10, a voltage (primary transfer bias) of the opposite polarity to the charging polarity (negative polarity) of the toner is applied to the base material of the intermediate transfer belt 15 by the primary transfer roll 16, and the toner images are sequentially superimposed on the surface of the intermediate transfer belt 15 to perform the primary transfer.

[0155] After the toner images are sequentially primarily transferred onto the surface of the intermediate transfer belt 15, the intermediate transfer belt 15 moves to transport the toner images to the secondary transfer unit 20. When the toner images are transported to the secondary transfer unit 20, the transport means rotates the paper feed roll 51 in accordance with the timing at which the toner images are transported to the secondary transfer unit 20, and paper K of the desired size is supplied from the paper storage unit 50. The paper K supplied by the paper feed roll 51 is transported by the transport roll 52 and reaches the secondary transfer unit 20 via the transport guide 53. Before reaching the secondary transfer unit 20, the paper K is temporarily stopped, and an alignment roll (not shown) rotates in accordance with the movement timing of the intermediate transfer belt 15 on which the toner images are held, thereby aligning the position of the paper K with the position of the toner image.

[0156] In the secondary transfer section 20, the secondary transfer roll 22 is pressed against the back roll 25 via the intermediate transfer belt 15. At this time, the paper K, which has been transported in time, is sandwiched between the intermediate transfer belt 15 and the secondary transfer roll 22. At this time, when a voltage (secondary transfer bias) of the same polarity as the charging polarity (negative polarity) of the toner is applied from the power supply roll 26, a transfer electric field is formed between the secondary transfer roll 22 and the back roll 25. Then, the unfixed toner images held on the intermediate transfer belt 15 are electrostatically transferred collectively onto the paper K in the secondary transfer section 20, which is pressed by the secondary transfer roll 22 and the back roll 25.

[0157] Thereafter, the paper K onto which the toner image has been electrostatically transferred is transported as it is after being peeled off from the intermediate transfer belt 15 by the secondary transfer roll 22, and is transported to a transport belt 55 provided downstream of the secondary transfer roll 22 in the paper transport direction. The transport belt 55 transports the paper K to the fixing device 60 at an optimal transport speed for the fixing device 60. The unfixed toner image on the paper K transported to the fixing device 60 is fixed onto the paper K by being subjected to a fixing process using heat and pressure by the fixing device 60. The paper K on which the fixed image has been formed is then transported to an ejected paper storage section (not shown) provided in the ejection section of the image forming apparatus.

[0158] On the other hand, after the transfer to the paper K is completed, the residual toner remaining on the intermediate transfer belt 15 is transported to the cleaning section as the intermediate transfer belt 15 rotates, and is removed from the intermediate transfer belt 15 by the cleaning back roll 34 and the intermediate transfer belt cleaner 35.

[0159] Although the present embodiment has been described above, the present invention is not limited to the above embodiment, and various modifications, changes, and improvements are possible. EXAMPLES

[0160] The present invention will be described in more detail below with reference to examples, although the present invention is not limited to the following examples.

[0161] <Example 1> (Formation of Resin Substrate Layer) A coating solution for forming a base layer containing polyamic acid (solid content concentration: 18% by mass) was applied onto a cylindrical mold, and the resulting coating film was baked at 380°C to form a cylindrical resin base layer (film thickness: 80 μm).

[0162] (Formation of elastic layer) Butyl acetate and carbon nanotubes (Showa Denko K.K.) were mixed in a mass ratio of 15:85 to prepare a dispersion (hereinafter also referred to as "CNT 15% dispersion"). The obtained dispersion was subjected to high-pressure dispersion treatment (conditions: liquid temperature 45°C, 50 MPa, 3 cycles (i.e., valve passage (pass number) 3 times)) using a high-pressure homogenizer (HC3, Sanmaru Machinery Co., Ltd.). Next, 50 parts by mass of silicone rubber stock solution (X-34-1053 manufactured by Shin-Etsu Chemical Co., Ltd., solid content concentration: 60% by mass, solvent: butyl acetate) was added to 50 parts by mass of the dispersion liquid after the high pressure dispersion treatment to prepare a precursor liquid. The obtained precursor liquid was stirred for 10 minutes in a planetary mixer (Aikosha Seisakusho Co., Ltd. ACM-5LVT) under the conditions of liquid temperature 30°C and vacuum drawing. As a result, a coating liquid for forming an elastic layer was obtained, which contained 20 mass % of aggregates (that is, specific aggregates) in the solid content, in which a plurality of carbon nanotubes were entangled with one another. Next, the obtained coating liquid for forming an elastic layer was applied onto the substrate layer to form a coating film, and the coating film was heated at 100° C. for 30 minutes to form an elastic layer with a thickness of 450 μm.

[0163] (Formation of release layer) A PFA tube (manufactured by Gunze Ltd.) having a thickness of 35 μm was placed on the elastic layer and heated at 200° C. for 120 minutes to form a release layer made of a fluororesin tube.

[0164] Through the above steps, a fixing belt was obtained.

[0165] <Examples 2 and 3> A fixing belt was produced in the same manner as in Example 1, except that the method for forming the elastic layer was changed to the following method. That is, in forming the elastic layer in Example 1, the high-pressure dispersion treatment was performed in two cycles, and further, the stirring time of the precursor liquid using a planetary mixer was changed to 45 minutes (Example 2) or 60 minutes (Example 3). Except for this, the elastic layer was formed in the same manner as in Example 1.

[0166] <Examples 4 to 8> A fixing belt was produced in the same manner as in Example 1, except that the method for forming the elastic layer was changed to the following method. That is, the elastic layer was formed in the same manner as in Example 1, except that the amount of the dispersion liquid after the high-pressure dispersion treatment and the amount of the silicone rubber stock solution were changed as follows: Example 4: 0.4 parts by weight of dispersion after high-pressure dispersion treatment, 99.6 parts by weight of silicone rubber stock solution Example 5: 14.75 parts by mass of dispersion after high-pressure dispersion treatment, 70 parts by mass of silicone rubber stock solution Example 6: 74.3 parts by mass of dispersion after high-pressure dispersion treatment, 34.5 parts by mass of silicone rubber stock solution Example 7: 80 parts by weight of dispersion after high-pressure dispersion treatment, 30 parts by weight of silicone rubber stock solution Example 8: 50 parts by weight of dispersion after high-pressure dispersion treatment, 15.28 parts by weight of silicone rubber stock solution

[0167] <Examples 9 to 12> A fixing belt was produced in the same manner as in Example 1, except that the method for forming the elastic layer was changed to the following method. That is, in forming the elastic layer in Example 1, a precursor liquid was prepared by changing the amount of the dispersion liquid after the high-pressure dispersion treatment and the amount of the silicone rubber stock liquid as follows. Next, the precursor liquid was stirred with a planetary mixer, and the 15% CNT dispersion liquid used in Example 1 was added in the amount shown below. The elastic layer was formed in the same manner as in Example 1, except that a coating liquid for forming an elastic layer, which had been further stirred with the planetary mixer under the conditions of a liquid temperature of 30°C and normal pressure for 1 minute, was used. Example 9: 33.15 parts by mass of dispersion after high-pressure dispersion treatment, 65 parts by mass of silicone rubber stock solution, 1.48 parts by mass of 15% CNT dispersion Example 10: 28.25 parts by mass of dispersion after high-pressure dispersion treatment, 100 parts by mass of silicone rubber stock solution, 42.35 parts by mass of 15% CNT dispersion Example 11: 21.2 parts by mass of dispersion after high-pressure dispersion treatment, 60.1 parts by mass of silicone rubber stock solution, 21.2 parts by mass of 15% CNT dispersion Example 12: 43.6 parts by mass of dispersion after high-pressure dispersion treatment, 65 parts by mass of silicone rubber stock solution, 2.3 parts by mass of 15% CNT dispersion

[0168] <Comparative Example 1> A fixing belt was produced in the same manner as in Example 1, except that the method for forming the elastic layer was changed to the following method. That is, 50 parts by mass of a silicone rubber stock solution (X-34-1053 manufactured by Shin-Etsu Chemical Co., Ltd., solid content concentration: 60% by mass, solvent: butyl acetate) was mixed with 50 parts by mass of the dispersion (CNT 15% dispersion) that was not subjected to high pressure dispersion treatment used in forming the elastic layer in Example 1 to prepare a precursor liquid, and the stirring time of the obtained precursor liquid with a planetary mixer was set to 1 minute to obtain a coating liquid for forming an elastic layer. An elastic layer was formed in the same manner as in Example 1, except that this coating liquid for forming an elastic layer was used.

[0169] <Comparative Example 2> A fixing belt was produced in the same manner as in Example 1, except that the method for forming the elastic layer was changed to the following method. An elastic layer was formed in the same manner as in Example 1, except that a silicone rubber stock solution (X-34-1053 manufactured by Shin-Etsu Chemical Co., Ltd., solid content concentration: 60 mass %, solvent: butyl acetate) was used as it was as a coating solution for forming an elastic layer.

[0170] <Comparative Example 3> A fixing belt was produced in the same manner as in Example 1, except that the method for forming the elastic layer was changed to the following method. That is, in forming the elastic layer in Example 1, the precursor liquid obtained using the dispersion liquid that had been subjected to two cycles of high-pressure dispersion treatment was stirred for 80 minutes in a planetary mixer (ACM-5LVT manufactured by Aikosha Seisakusho Co., Ltd.) under conditions of liquid temperature 30°C and vacuum drawing. In this manner, a coating liquid for forming an elastic layer was obtained, which contained 20 mass % of aggregates (that is, specific aggregates) in which a plurality of carbon nanotubes were entangled with one another. Next, the obtained coating liquid for forming an elastic layer was applied onto the substrate layer to form a coating film, and the coating film was heated at 100° C. for 30 minutes to form an elastic layer with a thickness of 450 μm.

[0171] <Measurement of thermal conductivity> The thermal conductivity of the elastic layer obtained in each example was measured according to the method already described.

[0172] <Measurement of Young's modulus> The Young's modulus of the elastic layer obtained in each example was measured according to the method already described.

[0173] <Offset evaluation> The fixing belt obtained in each example was mounted on the fixing device of an image forming apparatus (Versant 3100 Press, manufactured by Fuji Xerox Co., Ltd.). Using this image forming apparatus, 300,000 solid images with 100% image density and Cin100% were output on A4 paper. The conditions for fixing were an output speed (printing speed) of 60 sheets per minute (indicated as "60 ppm" in the table) or 120 sheets per minute (indicated as "120 ppm" in the table). Three types of A4 paper were used: plain paper (P paper manufactured by Fujifilm Business Innovation Co., Ltd.), thick paper (JD Coat 157 manufactured by Fujifilm Business Innovation Co., Ltd.), and embossed paper with large surface irregularities (Rezac 66 manufactured by Tokushu Tokai Paper Co., Ltd.). After the above output, the fixing belt was removed, and the surface of the removed fixing belt was visually observed to evaluate offset. The offset was evaluated according to the following criteria. A (◎): No offset was observed in the fixing belt. B (◯): Slight offset is observed on the fixing belt (1 to 3 places). C (△): Offset is observed in some parts (4 to 7 places) of the fixing belt. D(x): Numerous offsets (8 or more) are observed on the fixing belt.

[0174] [Table 1]

[0175] From the above results, it is understood that the fixing belt of this embodiment suppresses offset compared to the fixing belt of the comparative example, even when a recording medium having large surface irregularities such as embossed paper is used. It can also be seen that the fixing belt of this embodiment suppresses offset whether using plain paper or thick paper. [Explanation of symbols]

[0176] 60 Fixing device 62 Pressure Belt 63 Belt guide 64 Pressure Pad 64a Front clamping member 64b Peeling and clamping member 65 Retaining member 66 Halogen lamp 68 Sliding members 69 Thermosensor 70 Peeling member 71 Peeling Claw 72 Retaining member 80 Fixing device 82 Sliding member 84 Heating Belt 86 Fuser Belt Module 88 Pressure Roll 89A halogen heater 89 Heated pressure roll 90A halogen heater 90 Support Roll 92A halogen heater 92 Support Roll 94 Posture Correction Roll 96 Support member 98 Support Roll 100 Image forming device 110 Fixing belt 110A base material 110B Elastic layer 110C Release layer 200 Fixing device 211 Pressure Roll 212 Electromagnetic induction heating device 220 Belt

Claims

1. The film has a resin substrate layer, an elastic layer, and a release layer in this order, the elastic layer includes an elastic material and an aggregate formed by intertwining a plurality of fibrous carbons with each other, and the maximum diameter of the aggregate is 2% or more and 15% or less of the thickness of the elastic layer; The ratio of the minor axis Y to the major axis X of the aggregate (minor axis Y / major axis X) is 0.1 or more and 1.0 or less.

2. The fuser belt of claim 1 , wherein the elastic layer further comprises non-entangled fibrous carbon.

3. The fixing belt according to claim 2 , wherein when the content A of the aggregates and the content B of the non-entangled fibrous carbon are taken as A and B, respectively, the relationship A≧B is satisfied on a mass basis.

4. A ratio (A / (A+B)) of the content A of the aggregates to the total amount of the content A of the aggregates and the content B of the fibrous carbon that is not entangled with each other is, on a mass basis, The fixing belt according to claim 2 or 3, wherein the viscosity is 0.50 or more and 0.95 or less.

5. 5. The fixing belt according to claim 1, wherein the content of the aggregate is 0.1% by mass or more and 40% by mass or less with respect to the total mass of the elastic layer.

6. The fixing belt according to claim 5 , wherein the content of the aggregate is 10% by mass or more and 30% by mass or less with respect to the total mass of the elastic layer.

7. 7. The fixing belt according to claim 1, wherein the elastic layer has a Young's modulus of 0.2 MPa or more and 1.0 MPa or less.

8. 8. The fixing belt according to claim 1, wherein the fibrous carbon is a carbon nanotube.

9. The film has a resin substrate layer, an elastic layer, and a release layer in this order, The fixing belt according to any one of claims 1 to 6 and claim 8, wherein the elastic layer contains an elastic material and fibrous carbon, has a thermal conductivity of 1.0 W / m·K or more and 4.5 W / m·K or less, and has a Young's modulus of 0.2 MPa or more and 1.0 MPa or less.

10. A film-forming device comprising a resin substrate layer, an elastic layer, and a release layer in this order, the elastic layer includes an elastic material and an aggregate formed by intertwining a plurality of fibrous carbons with each other, and the maximum diameter of the aggregate is 2% or more and 15% or less of the thickness of the elastic layer; The elastic layer further comprises non-entangled fibrous carbon, A fixing belt, wherein, when the content of the aggregates is A and the content of the non-entangled fibrous carbon is B, the relationship A≧B is satisfied on a mass basis.

11. A film-forming device comprising a resin substrate layer, an elastic layer, and a release layer in this order, the elastic layer includes an elastic material and an aggregate formed by intertwining a plurality of fibrous carbons with each other, and the maximum diameter of the aggregate is 2% or more and 15% or less of the thickness of the elastic layer; The elastic layer further comprises non-entangled fibrous carbon, A ratio (A / (A+B)) of the content A of the aggregates to the total amount of the content A of the aggregates and the content B of the fibrous carbon that is not entangled with each other is, on a mass basis, A fixing belt having a viscosity of 0.50 or more and 0.95 or less.

12. A film-forming device comprising a resin substrate layer, an elastic layer, and a release layer in this order, the elastic layer includes an elastic material and an aggregate formed by intertwining a plurality of fibrous carbons with each other, and the maximum diameter of the aggregate is 2% or more and 15% or less of the thickness of the elastic layer; A fixing belt, wherein the content of the aggregate is 0.1% by mass or more and 40% by mass or less with respect to the total mass of the elastic layer.

13. A film-forming device comprising a resin substrate layer, an elastic layer, and a release layer in this order, the elastic layer includes an elastic material and an aggregate formed by intertwining a plurality of fibrous carbons with each other, and the maximum diameter of the aggregate is 2% or more and 15% or less of the thickness of the elastic layer; The content of the aggregate is 0.1% by mass or more and 40% by mass or less with respect to the total mass of the elastic layer, A fixing belt, wherein the content of the aggregate is 10% by mass or more and 30% by mass or less with respect to the total mass of the elastic layer.

14. A film-forming device comprising a resin substrate layer, an elastic layer, and a release layer in this order, the elastic layer includes an elastic material and an aggregate formed by intertwining a plurality of fibrous carbons with each other, and the maximum diameter of the aggregate is 2% or more and 15% or less of the thickness of the elastic layer; The fuser belt, wherein the fibrous carbon is a carbon nanotube.

15. A first rotating body and a second rotating body arranged in contact with an outer surface of the first rotating body, At least one of the first rotating body and the second rotating body is the fixing belt according to any one of claims 1 to 14, a fixing device for fixing a toner image formed on a surface of the recording medium by inserting the recording medium through a contact portion between the first rotating body and the second rotating body;

16. An image carrier; a charging means for charging the surface of the image carrier; an electrostatic latent image forming means for forming an electrostatic latent image on the charged surface of the image carrier; a developing unit for developing the electrostatic latent image formed on the surface of the image carrier with a developer containing a toner to form a toner image; a transfer means for transferring the toner image onto a surface of a recording medium; A fixing unit that fixes the toner image onto the recording medium, the fixing unit being configured as claimed in claim 15; An image forming apparatus comprising:

Images