Fixing apparatus and image forming apparatus

Abstract

Providing a fixing device that suppresses both image displacement and paper wrinkles caused by paper slippage on the fixing surface. 【Solution means】A pressure belt including a heating roll, a surface layer disposed in contact with the heating roll and being a cured product of a composition containing a compound represented by the following formula 1, a pressing member disposed on the inner peripheral surface of the pressure belt and pressing the pressure belt from the inner peripheral surface of the pressure belt against the heating roll, a sliding member interposed between the inner peripheral surface of the pressure belt and the pressing member, and a lubricant interposed between the inner peripheral surface of the pressure belt and the sliding member. (R 1 3SiO 1 / 2 ) a (R 1 2SiO 2 / 2 ) b (R 1 SiO 3 / 2 ) c (SiO 4 / 2 ) d (R 2 O 1 / 2 ) e Formula 1

Description

[Technical Field]

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

[0002] For example, Patent Document 1 discloses "an elastic body formed by an addition-type silicone rubber elastic material, characterized in that the addition-type silicone rubber elastic material has a cured polysiloxane mixture having at least (a) a linear dimethylpolysiloxane with terminal vinyl group sealing having a viscosity of 80,000 poise or more at 25°C, and (b) a resinous organopolysiloxane with a viscosity of 10 poise or more at 25°C, having a block copolymer in the same molecule having a resin segment having two or more vinyl groups and containing at least one of tetrafunctional or trifunctional properties, and a linear oil segment having at least 100 or more consecutive difunctional constituent units." [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Patent Publication No. 2617858 [Overview of the project] [Problems that the invention aims to solve]

[0004] The object of this disclosure is to provide a fixing device that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to cases where "the coefficient of dynamic friction μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the coefficient of dynamic friction μ2 between the back surface of the paper and the outer surface of the pressure belt are μ1 = μ2 or μ1 < μ2," or "the surface layer of the pressure belt is a fluororesin layer." [Means for solving the problem]

[0005] Specific means for solving the above problems include the following aspects. <1> A heating roll, A pressure belt disposed in contact with the heating roll and having a surface layer that is a cured product of a composition containing a compound represented by the following formula 1, A pressing member disposed on the inner peripheral surface of the pressure belt and pressing the pressure belt from the inner peripheral surface of the pressure belt toward the heating roll, A sliding member interposed between the inner peripheral surface of the pressure belt and the pressing member, A lubricant interposed between the inner peripheral surface of the pressure belt and the sliding member, And a fixing device comprising the same. (R 3SiO 1 / 2 ) a (R 1 2SiO 2 / 2 ) b (R 1 SiO 3 / 2 ) c (SiO 4 / 2 ) d (R 2 O 1 / 2 ) e Formula 1 (In formula 1, R 1 represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an aryl group, a group represented by -C(=O)-CR 3 3, or a monovalent organic group having a reactive group. A plurality of R 1 may be the same or different from each other. R 2 represents a hydrogen atom or an alkyl group. A plurality of R 2 may be the same or different from each other. R 3 represents a hydrogen atom, a methyl group, or an ethyl group. A plurality of R 3 may be the same or different from each other. The monovalent organic group may be substituted with a halogen atom, a hydroxyl group, an alkoxy group, an aryloxy group, an aralkyloxy group, or an oxy group. The alkyl group, alkenyl group, alkynyl group, aralkyl group, and aryl group may have substituents. a, b, d, and e are each independently between 0 and 1, c is greater than 0 and less than or equal to 1, and a + b + c + d + e = 1. <2> The coefficient of dynamic friction μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the coefficient of dynamic friction μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1 > μ2. <1> The fixing device described above. <3> The difference Δμ(μ1-μ2) between the coefficient of dynamic friction μ1 and the coefficient of dynamic friction μ2 is 0.10 or more and 1.00 or less, <2> The fixing device described above. <4> A heated roll and A pressure belt comprising a surface layer which is a cured product of a composition containing a silsesquioxane compound and is disposed in contact with the aforementioned heating roll, A pressing member is disposed on the inner circumferential surface of the pressure belt and presses the pressure belt against the heating roll from the inner circumferential surface of the pressure belt, A sliding member interposed between the inner circumferential surface of the pressure belt and the pressing member, A lubricant interposed between the inner circumferential surface of the pressure belt and the sliding member, Equipped with, A fixing device in which the coefficient of dynamic friction μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the coefficient of dynamic friction μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1 > μ2. <5> The difference Δμ(μ1-μ2) between the coefficient of dynamic friction μ1 and the coefficient of dynamic friction μ2 is 0.20 or more and 0.80 or less, <3> or <4> The fixing device described above. <6> The difference Δμ(μ1-μ2) between the coefficient of dynamic friction μ1 and the coefficient of dynamic friction μ2 is 0.30 or more and 0.60 or less. <5> The fixing device described above. <7> The coefficient of dynamic friction μ1 is 0.40 or more and 0.90 or less, <2> ~ <6> A fixing device as described in any one of the items. <8> The coefficient of dynamic friction μ2 is 0.10 or more and 0.70 or less, <2> ~ <7> A fixing device as described in any one of the items. <9> The silsesquioxane compound includes the compound represented by the following formula 1, <4> ~ <8> A fixing device as described in any one of the items. (R 1 3SiO 1 / 2 ) a (R 1 2SiO 2 / 2 ) b (R 1 SiO 3 / 2 ) c (SiO 4 / 2 ) d (R 2 O 1 / 2 ) e formula 1 (In formula 1, R 1 This includes hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, aryl groups, and -C(=O)-CR groups. 3 Represents a group represented by 3, or a monovalent organic group having a reactive group. Multiple R 1 These may be the same or different. R 2 R represents a hydrogen atom or an alkyl group. Multiple R 2 These may be the same or different. R 3 R represents a hydrogen atom, a methyl group, or an ethyl group. Multiple R 3 These may be the same or different. The monovalent organic group may be substituted with a halogen atom, a hydroxyl group, an alkoxy group, an aryloxy group, an aralkyloxy group, or an oxy group. The alkyl group, alkenyl group, alkynyl group, aralkyl group, and aryl group may have substituents. a, b, d, and e are each independently between 0 and 1, c is greater than 0 and less than or equal to 1, and a + b + c + d + e = 1. <10> The surface layer of the pressure belt has a tensile modulus of 100 MPa or more at 150°C. <1> ~ <9> A fixing device as described in any one of the items. <11> The surface layer of the pressure belt has a tensile modulus of elasticity of 1000 MPa or more and 3500 MPa or less at 150°C. <1> ~ <10> A fixing device as described in any one of the items. <12> The surface layer of the pressure belt has a surface roughness Ra of 0.90 μm or less. <1> ~ <11> A fixing device as described in any one of the items. <13> Image holder and, A charging device for charging the surface of the image holder, An electrostatic latent image forming apparatus for forming an electrostatic latent image on the surface of the charged image holder, A developing apparatus that contains a developer containing toner, and uses the developer to develop an electrostatic latent image formed on the surface of the image holder to form a toner image, A transfer device for transferring the toner image onto the surface of a recording medium, The toner image is fixed to the surface of the recording medium. <1> ~ <12> A fixing device as described in any one of the items, An image forming apparatus equipped with the following features. [Effects of the Invention]

[0006] <1> or <9> According to the invention, a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to a case where the surface layer of the pressure belt is a fluororesin layer. <2> According to the invention, compared to the case where the dynamic friction coefficient μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the dynamic friction coefficient μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1 = μ2 or μ1 < μ2, a ​​fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles. <3> According to the invention, a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to cases where the difference Δμ(μ1-μ2) between the dynamic friction coefficient μ1 and the dynamic friction coefficient μ2 is less than 0.10 or greater than 1.00. <4> According to the invention, compared to the case where the dynamic friction coefficient μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the dynamic friction coefficient μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1 = μ2 or μ1 < μ2, a ​​fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles. <5> According to the invention, a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to cases where the difference Δμ(μ1-μ2) between the dynamic friction coefficient μ1 and the dynamic friction coefficient μ2 is less than 0.20 or greater than 0.80. <6> According to the invention, a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to cases where the difference Δμ(μ1-μ2) between the dynamic friction coefficient μ1 and the dynamic friction coefficient μ2 is less than 0.30 or greater than 0.60. <7> According to the invention, a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to cases where the dynamic friction coefficient μ1 is less than 0.40 or greater than 0.90. <8> According to the invention, a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to cases where the dynamic friction coefficient μ2 is less than 0.10 or greater than 0.70. <10> According to the invention, a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the tensile modulus of elasticity of the surface layer of the pressure belt at 150°C is less than 100 MPa. <11> According to the invention, compared to cases where the tensile modulus of elasticity of the surface layer of the pressure belt at 150°C is less than 1000 MPa or more than 3500 MPa, a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles. <12> According to the invention, a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the surface roughness Ra of the surface layer of the pressure belt exceeds 0.90 μm. <13> According to the invention, compared to the case where the surface layer of the pressure belt is a fluororesin layer, or the case where the dynamic friction coefficient μ1 between the surface of the heating roll and the surface on which the toner image is fixed on the paper, and the dynamic friction coefficient μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1 = μ2 or μ1 < μ2, a ​​fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a schematic diagram showing an example of an image forming apparatus according to this embodiment. [Figure 2] Figure 2 is a schematic diagram showing an example of a fixing device according to this embodiment. [Modes for carrying out the invention]

[0008] The following describes an example of an embodiment of this disclosure. These descriptions and examples are illustrative and do not limit the scope of the invention. In numerical ranges described stepwise within this specification, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described stepwise. Furthermore, in numerical ranges described within this specification, the upper or lower limit of that range may be replaced with the values ​​shown in the examples.

[0009] Each component may contain multiple types of the relevant substance. When referring to the amount of each component in a composition, if there are multiple substances corresponding to each component in the composition, unless otherwise specified, it refers to the total amount of those multiple substances present in the composition.

[0010] When describing embodiments with reference to the drawings, components having substantially the same function will be given the same reference numeral throughout the drawings, and redundant explanations may be omitted.

[0011] <Fusing device / Image forming apparatus>

[0012] The fixing device according to the first embodiment comprises a heating roll, a pressure belt disposed in contact with the heating roll and having a surface layer which is a cured product of a composition containing a compound represented by the following formula 1, a pressing member disposed on the inner circumferential surface of the pressure belt and pressing the pressure belt from the inner circumferential surface of the pressure belt against the heating roll, a sliding member interposed between the inner circumferential surface of the pressure belt and the pressing member, and a lubricant interposed between the inner circumferential surface of the pressure belt and the sliding member. (R 1 3SiO 1 / 2 ) a (R 1 2SiO 2 / 2 ) b (R 1 SiO 3 / 2 ) c (SiO 4 / 2 ) d (R 2 O 1 / 2 ) e formula 1 (In formula 1, R 1 This includes hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, aryl groups, and -C(=O)-CR groups. 3 Represents a group represented by 3, or a monovalent organic group having a reactive group. Multiple R 1 These may be the same or different. R 2 R represents a hydrogen atom or an alkyl group. Multiple R 2 These may be the same or different. R 3 R represents a hydrogen atom, a methyl group, or an ethyl group. Multiple R 3 These may be the same or different. The monovalent organic group may be substituted with a halogen atom, a hydroxyl group, an alkoxy group, an aryloxy group, an aralkyloxy group, or an oxy group. The alkyl group, alkenyl group, alkynyl group, aralkyl group, and aryl group may have substituents. a, b, d, and e are each independently between 0 and 1, c is greater than 0 and less than or equal to 1, and a + b + c + d + e = 1.

[0013] The fixing device according to the second embodiment comprises a heating roll, a pressure belt disposed in contact with the heating roll and having a surface layer which is a cured product of a composition containing a silsesquioxane compound, a pressing member disposed on the inner circumferential surface of the pressure belt and pressing the pressure belt from the inner circumferential surface of the pressure belt against the heating roll, a sliding member interposed between the inner circumferential surface of the pressure belt and the pressing member, and a lubricant interposed between the inner circumferential surface of the pressure belt and the sliding member, wherein the coefficient of dynamic friction μ1 between the surface of the heating roll and the surface on the paper that fixes the toner image, and the coefficient of dynamic friction μ2 between the back surface of the paper and the outer circumferential surface of the pressure belt satisfy the relationship μ1 > μ2.

[0014] Hereinafter, matters common to the first and second embodiments will be referred to as this embodiment. Hereinafter, a fixing device comprising a heating roll, a pressure belt disposed in contact with the heating roll and having a surface layer, a pressing member disposed on the inner circumferential surface of the pressure belt and pressing the pressure belt against the heating roll from the inner circumferential surface of the pressure belt, a sliding member interposed between the inner circumferential surface of the pressure belt and the pressing member, and a lubricant interposed between the inner circumferential surface of the pressure belt and the sliding member will be referred to as a specific fixing device.

[0015] The image forming apparatus according to this embodiment comprises an image holder, a latent image forming apparatus for forming a latent image on the surface of the image holder, a developing apparatus for developing the latent image into a toner image using a developer, a transfer apparatus for transferring the developed toner image onto a recording medium, and a fixing apparatus for fixing the toner image on the recording medium. The fixing apparatus according to this embodiment is applied to the image forming apparatus according to this embodiment.

[0016] Conventionally, to form an image in an electrophotographic image forming device such as a printer, copier, or facsimile, a toner image is transferred onto the paper, and then the paper on which the toner image has been transferred is heated and pressurized in a fixing device to fix the toner image to the surface of the paper.

[0017] Conventionally, various types of fixing devices have been proposed, and one of them is the specific fixing device described above. In this specific fixing device, a pressure belt containing fluororesin in its surface layer has been proposed from the viewpoint of maintaining the wear resistance of the pressure belt. However, when a pressure belt containing fluororesin in its surface layer is used, when fixing an image at a high temperature (e.g., 150°C), the dynamic friction force tends to be greater on the side applying pressure than on the side fixing the image due to the low slipperiness of the surface layer. As a result, the transport timing of the paper being transported to the position where the toner image is to be transferred tends to lag behind the transport timing of the toner image being transported to the transfer position by the pressure belt. This can cause image misalignment on the paper. Consequently, the paper tends to slip on the fixing surface, leading to paper wrinkles and image misalignment.

[0018] In contrast, the fixing device according to this embodiment, having the above configuration, suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles. The mechanism of action is not entirely clear, but it is presumed to be as follows.

[0019] The fixing device according to the first embodiment includes a compound represented by formula 1 in the surface layer of the pressure belt. Due to its structural characteristics, the compound represented by formula 1 has intermediate physical properties between inorganic silica and organic silicone. Therefore, the surface layer containing the compound represented by formula 1 has both inorganic characteristics such as heat resistance and hardness, and organic characteristics such as flexibility and processability. As a result, even when fixing images at high temperatures (e.g., 150°C), the amount of deformation of the surface layer of the pressure belt is kept to a minimum, and the grip force between the surface layer and the paper is reduced. As a result, the frictional force on the pressure side is lower than on the fixing side, making it possible to prevent slippage on the fixing surface and preventing paper wrinkles and image misalignment.

[0020] In the fixing device according to the second embodiment, the coefficient of dynamic friction μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the coefficient of dynamic friction μ2 between the back surface of the paper and the outer surface of the pressure belt, satisfy the relationship μ1 > μ2. Therefore, even when fixing the image, the amount of deformation of the surface layer is kept to a minimum, and the gripping force between the surface layer and the paper is reduced. As a result, the frictional force on the pressure side is lower than that on the fixing side, making it possible to prevent slippage on the fixing surface and preventing paper wrinkles and image misalignment.

[0021] [Coefficient of kinetic friction] In the fixing device according to the first embodiment, it is preferable that the dynamic friction coefficient μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the dynamic friction coefficient μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1 > μ2. In the fixing device according to the second embodiment, the coefficient of dynamic friction μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the coefficient of dynamic friction μ2 between the back surface of the paper and the outer surface of the pressure belt, satisfy the relationship μ1 > μ2. When the relationship μ1 > μ2 is satisfied, the deformation of the surface layer of the pressure belt is kept to a minimum even when fixing the image at high temperatures, and the grip force between the surface layer and the paper is further reduced. As a result, the frictional force on the pressure side is lower than on the fixing side, which prevents slippage on the fixing surface and further prevents paper wrinkles and image misalignment.

[0022] The back side of the paper refers to the side of the paper that comes into contact with the outer edge of the pressure belt.

[0023] The following describes preferred embodiments of the coefficient of dynamic friction that are common to both the first and second embodiments.

[0024] In the fixing device according to this embodiment, the difference Δμ(μ1-μ2) between the dynamic friction coefficient μ1 and the dynamic friction coefficient μ2 is preferably 0.10 or more and 1.00 or less, more preferably 0.20 or more and 0.80 or less, and even more preferably 0.30 or more and 0.60 or less. When the difference Δμ(μ1-μ2) is between 0.30 and 0.60, the deformation of the surface layer of the pressure belt is sufficiently kept small when fixing the image at high temperature, and the grip force between the surface layer and the paper is further reduced.

[0025] The coefficient of dynamic friction μ1 is preferably 0.30 or more and 0.90 or less, more preferably 0.40 or more and 0.80 or less, and even more preferably 0.50 or more and 0.70 or less. When the coefficient of dynamic friction μ1 is 0.30 or higher, the amount of deformation of the surface layer of the heating roll is sufficiently suppressed when fixing the image at high temperatures, and the grip force between the surface of the heating roll and the paper is further reduced. When the coefficient of dynamic friction μ1 is 0.90 or less, the deformation of the surface layer of the heating roll is sufficiently kept small when fixing the image at high temperatures, and the frictional force on the pressing side becomes larger than that on the fixing side, which is suppressed.

[0026] The coefficient of dynamic friction μ2 is preferably 0.10 or more and 0.75 or less, more preferably 0.15 or more and 0.65 or less, and even more preferably 0.20 or more and 0.55 or less. When the coefficient of dynamic friction μ2 is 0.10 or higher, the excessive slipperiness of the surface layer of the pressure belt is suppressed when fixing images at high temperatures, and the difference in frictional force between the fixing side and the pressure side becomes appropriate. As a result, slippage on the fixing surface is better prevented. When the coefficient of dynamic friction μ2 is 0.75 or less, the deformation of the surface layer of the pressure belt is sufficiently kept small when fixing the image at high temperatures, and the frictional force on the pressure side becomes larger than that on the fixing side.

[0027] The method for setting the dynamic friction coefficient μ1 within the above range is not particularly limited, but examples include a method in which the surface layer of the heating roll is a layer containing fluororesin; or a method in which a release oil is present on the surface of the fluororubber.

[0028] The method for setting the coefficient of dynamic friction μ2 and the difference Δμ(μ1-μ2) within the above range is not particularly limited, but one example is a method in which the surface layer of the pressure belt (i.e., the outer surface that contacts the back surface of the paper) is made of a cured film of a composition containing a silsesquioxane compound (more preferably a compound represented by formula 1).

[0029] The coefficients of dynamic friction μ1 and μ2 are measured by the following method. The test will be conducted in accordance with the JIS standard "Plastics - Films and Sheets - Test Method for Coefficient of Friction" (JIS K7125 (1999)). Specifically, the coefficient of dynamic friction between a transparent protective film placed on a horizontal stand and a sheet of copy paper (in this measurement method, "Fujifilm Business Innovation Co., Ltd., color / monochrome paper C2") fixed to the underside of a block-shaped weight will be measured using a Haydon friction force measuring device. The friction force will be measured when the contact area is 40 cm² (63 mm × 63 mm), a load of 1.64 kPa (200 g) is applied, and the paper is pulled at a speed of 100 mm / min (1.67 mm / sec). The coefficient of dynamic friction will be calculated by dividing the friction force by the vertical load from the weight. Since errors usually occur in the measurement of the coefficient of friction, the average value of five measurements will be taken. (Note that when the coefficient of kinetic friction is high, exceeding 0.9, a phenomenon called stick-slip, where the frictional force fluctuates significantly and periodically, is more likely to occur, making it difficult to measure the coefficient of kinetic friction.) The numerical values ​​described herein were measured by the method described above.

[0030] Hereinafter, an example of an image forming apparatus and a fixing apparatus according to this embodiment will be described with reference to the drawings. Figure 1 is a schematic diagram showing an example of an image forming apparatus according to this embodiment. Figure 2 is a schematic diagram showing an example of a fixing device according to this embodiment.

[0031] [Configuration of the image forming apparatus] As shown in Figure 1, the image forming apparatus 100 according to this embodiment is equipped with first to fourth electrophotographic process cartridges 10Y, 10M, 10C, and 10K (an example of an image forming unit) that output images of yellow (Y), magenta (M), cyan (C), and black (K) based on color-separated image data. These process cartridges 10Y, 10M, 10C, and 10K are arranged side by side, spaced apart from each other, along the outer surface of the intermediate transfer belt 20. These process cartridges 10Y, 10M, 10C, and 10K are detachable from the main body of the image forming apparatus.

[0032] Above each process cartridge 10Y, 10M, 10C, and 10K (in Figure 1), an intermediate transfer belt 20 is provided as an intermediate transfer body, with its outer surface facing each process cartridge. The intermediate transfer belt 20 is wound around drive rollers 22, which are spaced apart from each other, and support rollers 24 that are in contact with the inner surface of the intermediate transfer belt 20, and is provided with tension. It is designed to travel endlessly in the direction from the first process cartridge 10Y to the fourth process cartridge 10K.

[0033] The support roller 24 is pressed away from the drive roller 22 by an elastic member such as a spring (not shown), and tension is applied to the intermediate transfer belt 20 wound between them. In addition, an intermediate transfer body cleaning device 20a is provided on the outer circumferential surface of the intermediate transfer belt 20, facing the drive roller 22.

[0034] Since the first to fourth process cartridges 10Y, 10M, 10C, and 10K have substantially the same configuration, the first process cartridge 10Y, which forms the yellow image and is positioned upstream in the direction of travel of the intermediate transfer belt, will be described as a representative example. Furthermore, by assigning the same reference numerals to the same parts as the first process cartridge 10Y, but with magenta (M), cyan (C), and black (K) instead of yellow (Y), the descriptions of the second to fourth process cartridges 10M, 10C, and 10K will be omitted.

[0035] The first process cartridge 10Y has a photoreceptor 1Y that acts as an image holder. Around the photoreceptor 1Y, a charging roller (an example of a charging device) 2Y, a developing device 4Y, and a photoreceptor cleaning device 6Y are arranged in order. These are integrally configured within the housing 11Y. Similarly, in the first process cartridges 10M to 10Y, each component is integrally configured within the housing 11M to 11Y. Here, the charging roller 2Y is a charging roller that charges the surface of the photoreceptor 1Y to a predetermined potential. The developing device 4Y is a developing device that develops the electrostatic latent image by supplying charged toner contained in the developer to the electrostatic latent image. The photoreceptor cleaning device 6Y is a photoreceptor cleaning device that removes toner remaining on the surface of the photoreceptor 1Y after primary transfer.

[0036] The image forming unit is then configured with a first process cartridge 10Y, a primary transfer roller 5Y (an example of a primary transfer device) that transfers the developed toner image onto an intermediate transfer belt 20, and an exposure device 3 that exposes a charged surface with a laser beam 3Y based on a color-separated image signal to form an electrostatic latent image. The charging roller 2Y and the exposure device 3 are examples of a latent image forming apparatus.

[0037] The primary transfer roller 5Y is positioned inside the intermediate transfer belt 20, facing the photoreceptor 1Y. Furthermore, each of the primary transfer rollers 5Y, 5M, 5C, and 5K is connected to a bias power supply (not shown) that applies the primary transfer bias. Each bias power supply varies the transfer bias applied to each primary transfer roller through control by a control unit (not shown).

[0038] [Configuration of the fixing device] As shown in Figure 2, the fixing device 28 is equipped with a heating roll 30 and a pressure belt 40, with the heating roll 30 and the pressure belt 40 positioned opposite each other. The pressure belt 40 is pressed against the heating roll 30 by a pressing pad 50 (an example of a pressing member) positioned inside its circumference. The pressure belt 40 is pressed against the heating roll 30 to form a contact portion. The pressure belt 40 is then guided along the belt travel guide 52 and is driven by the driving force received from the heating roll 30. A sliding sheet 60 (an example of a sliding member) is interposed between the pressure belt 40 and the pressure pad 50. A lubricant 62 (an example of a lubricant) is interposed between the sliding sheet 60 and the inner circumferential surface of the pressure belt 40. The lubricant 62 is supplied to the inner circumferential surface of the pressure belt 40 by a lubricant supply member 64 provided on a part of the belt running guide 52, for example, and is interposed between the sliding sheet 60 and the inner circumferential surface of the pressure belt 40. In Figure 2, T represents the toner image.

[0039] [Compression belt 40] The pressure belt has a surface layer. The pressure belt 40 may be a single layer of surface material constituting the inner circumferential surface of the pressure belt 40, or it may be a laminate having a resin base material layer constituting the inner circumferential surface of the pressure belt 40, an elastic layer provided on the resin base material layer, and a surface layer provided on the elastic layer, or it may be a laminate having a resin base material layer constituting the inner circumferential surface of the pressure belt 40 and a surface layer provided on the resin base material layer.

[0040] (Surface layer) In the first embodiment, the surface layer is a cured product of a composition containing the compound represented by Formula 1. In the first embodiment, the composition may further contain silsesquioxane compounds other than the compound represented by Formula 1. In the second embodiment, the surface layer is a cured product of a composition containing a silsesquioxane compound. In the second embodiment, the silsesquioxane compound preferably contains a compound represented by Formula 1, from the viewpoint of adjusting the frictional force on the pressurized side to be lower than that on the fixing side, thereby further preventing slippage on the fixing surface.

[0041] • Silsesquioxane compounds Silsesquioxane compounds are given by formula (R 1 SiO 3 / 2 ) n This is a general term for compounds having the constituent unit 3' represented by the formula, 1 R represents an organic group, and n represents a positive number greater than or equal to 2. Multiple R groups exist within the constituent unit 3'. 1 These may be the same organic group or different organic groups. The silsesquioxane compound may be used alone or in combination of two or more.

[0042] In the three constituent units, R 1 Examples of organic groups represented by include polymerizable functional groups, hydroxyl groups, siloxy groups, hydrocarbon groups, hydrocarbon groups in which one or more methylene groups are replaced by carbonyl groups, hydrocarbon groups in which one or more carbon atoms are replaced by heteroatoms (oxygen atoms, nitrogen atoms, or sulfur atoms), or groups that combine these.

[0043] Examples of siloxy groups include monoalkylsiloxy groups, dialkylsiloxy groups, and trialkylsiloxy groups. Among these, dialkylsiloxy groups and trialkylsiloxy groups are preferred, with trialkylsiloxy groups being more preferred.

[0044] Examples of hydrocarbon groups include aliphatic hydrocarbon groups and aromatic hydrocarbon groups. Among the above, aliphatic hydrocarbon groups with 1 to 20 carbon atoms are preferred, and hydrocarbon groups with 1 to 15 carbon atoms are more preferred. The aliphatic hydrocarbon group may be linear, branched, or alicyclic. The aliphatic hydrocarbon group may be substituted with substituents such as halogen atoms, hydroxyl groups, amino groups, or aryl groups.

[0045] Examples of aromatic hydrocarbon groups include phenyl groups, naphthyl groups, and anthracenyl groups. Among these, aromatic hydrocarbon groups having 6 to 18 carbon atoms are preferred, and aromatic hydrocarbon groups having 6 to 14 carbon atoms are more preferred. Aromatic hydrocarbon groups may be substituted with substituents such as halogen atoms, hydroxyl groups, amino groups, alkyl groups, and alkoxy groups.

[0046] As for polymerizable functional groups, R in the compound represented by formula 1 described later is 1 Similar embodiments to the polymerizable functional group represented by can be cited.

[0047] The three-dimensional structure of a silsesquioxane compound may be cage-like, ladder-like, or random. Cage-like silsesquioxane compounds are a concept that encompasses both "incomplete cage-like" compounds, where part of the silsesquioxane skeleton has a cage-like structure, and "complete cage-like" compounds, where the entire silsesquioxane skeleton has a cage-like structure.

[0048] Compound represented by formula 1 The compounds represented by Formula 1 below are a type of silsesquioxane compound that can take on various skeletal structures, with the main chain skeleton consisting of Si-O bonds. The compounds represented by Formula 1 may be one type or two or more types.

[0049] (R 1 3SiO 1 / 2 ) a (R 1 2SiO 2 / 2 ) b (R 1 SiO 3 / 2 ) c (SiO 4 / 2 ) d (R 2 O 1 / 2 ) e formula 1 In formula 1, R 1 This includes hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, aryl groups, and -C(=O)-CR groups. 3 This represents a group represented by 3, or a monovalent organic group having a reactive group. A plurality of Rs 1 may be the same or different from each other. R 2 represents a hydrogen atom or an alkyl group. A plurality of Rs 2 may be the same or different from each other. R 3 represents a hydrogen atom, a methyl group, or an ethyl group. A plurality of Rs 3 may be the same or different from each other. The monovalent organic group may be substituted with a halogen atom, a hydroxy group, an alkoxy group, an aryloxy group, an aralkyloxy group, or an oxy group. The alkyl group, alkenyl group, alkynyl group, aralkyl group, and aryl group may have a substituent. a, b, d, and e are each independently 0 or more and 1 or less, c is more than 0 and 1 or less, and a + b + c + d + e = 1. Note that a, b, c, d, and e represent the average value of the molar ratio of each constituent unit contained in one molecule of the compound represented by Formula 1. <0OO0474>

[0050] The compound represented by Formula 1 is “R 1 3SiO 1 / 2 ” (hereinafter referred to as “constituent unit 1”), “R 1 2SiO 2 / 2 ” (hereinafter referred to as “constituent unit 2”), “R 1 SiO 3 / 2 ” (hereinafter referred to as “constituent unit 3”), “SiO 4 / 2 ” (hereinafter referred to as “constituent unit 4”), and “R 1 O 1 / 2 ” (hereinafter referred to as “constituent unit 5”).

[0051] Each of constituent units 1 to 5 in Formula 1 may be only one kind or two or more kinds. Further, the sequence order of the constituent units is not limited to the sequence order represented by Formula 1 and is not particularly limited.

[0052] The compound represented by Formula 1 is constituent unit 3 (that is, “R 1 SiO​It contains at least one constituent unit represented by ''. In other words, in Equation 1, c is a positive number greater than or equal to 0 and less than or equal to 1. The compound represented by formula 1 more preferably contains both constituent unit 3 and constituent unit 2. That is, it is preferable that in formula 1, b and c are independently positive numbers greater than 0 and less than or equal to 1, and a, d, and e are positive numbers in the range of 0 or a+b+c+d+e=1. The compound represented by formula 1 may consist only of three constituent units (i.e., c may be 1, and a, b, d, and e may all be 0).

[0053] In Formula 1, the reactive group is preferably at least one selected from the group consisting of (meth)acryloyl group, oxetanyl group, epoxy group, methyl group, and phenyl group; more preferably at least one selected from the group consisting of polymerizable functional group, aryl group, and alkyl group; and even more preferably at least one selected from the group consisting of (meth)acryloyl group, oxetanyl group, epoxy group, methyl group, and phenyl group.

[0054] Multiple R in constituent units 1-3 in Equation 1 1 These may be the same or different.

[0055] -Component Unit 1- Constituent unit 1 (that is, "R 1 3SiO 1 / 2 R in the constituent unit represented by " 1 The groups represented are hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, aryl groups, and -C(=O)-CR 3 3. At least one selected from the group consisting of a monovalent organic group having a reactive group (hereinafter also referred to as a "polymerizable functional group"). 1 It is preferable that it is at least one selected from the group consisting of a hydrogen atom, a polymerizable functional group, an aryl group, and an alkyl group, and more preferably at least one selected from the group consisting of a polymerizable functional group, an aryl group, and an alkyl group. Multiple R in this structural unit1 These may be the same or different.

[0056] R of this constituent unit 1 R may be a hydrogen atom. 1 When the atom is a hydrogen atom, for example, if at least one of the constituent units and another constituent unit comprises an organic group having 2 to 10 carbon atoms (hereinafter also simply referred to as an unsaturated organic group) that contains a carbon-carbon unsaturated bond capable of hydrosilylation and is included in the polymerizable functional group, then a crosslinking reaction can occur between these units.

[0057] R of this constituent unit 1 The alkyl group may be an alkyl group. The alkyl group may be either an aliphatic group or an alicyclic group, and may be either linear or branched. The alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms, even more preferably 1 to 2 carbon atoms, and particularly preferably 1 carbon atom, i.e., a methyl group. Specific examples of alkyl groups with 1 to 10 carbon atoms include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, etc.

[0058] R of this constituent unit 1 The group may be an alkenyl group. The alkenyl group may be an aliphatic group, an alicyclic group, or an aromatic group, and may be linear or branched. The number of carbon atoms in the alkenyl group is preferably 1 to 10. Specific examples of alkenyl groups with 1 to 10 carbon atoms include ethenyl (vinyl) group, orthostyryl group, metastyryl group, parastyryl group, 1-propenyl group, 2-propenyl (allyl) group, 1-butenyl group, 1-pentenyl group, 3-methyl-1-butenyl group, phenylethenyl group, allyl (2-propenyl) group, octenyl (7-octen-1-yl) group, and the like.

[0059] R of this constituent unit 1The group may be an alkynyl group. The alkynyl group may be an aliphatic group, an alicyclic group, or an aromatic group, and may be linear or branched. Preferably, the alkynyl group has 1 to 10 carbon atoms. Specific examples of alkynyl groups include ethynyl group, 1-propynyl group, 1-butynyl group, 1-pentynyl group, 3-methyl-1-butynyl group, and phenylbutynyl group.

[0060] R of this constituent unit 1 This may be an aryl group. The aryl group preferably has 6 to 20 carbon atoms, more preferably 6 to 10 carbon atoms, and even more preferably 6 carbon atoms, i.e., a phenyl group. Examples of aryl groups with 6 to 20 carbon atoms include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, and the like.

[0061] R of this constituent unit 1 This may be an aralkyl group. The aralkyl group preferably has 7 to 20 carbon atoms, and more preferably 7 to 10 carbon atoms. Examples of aralkyl groups with 7 to 20 carbon atoms include phenylalkyl groups such as benzyl groups.

[0062] R of this constituent unit 1 is -C(=O)-CR 3 3 is also acceptable. 3 R represents a hydrogen atom, a methyl group, or an ethyl group. 3 It is preferable that it is a methyl group. 3 If you have multiple R 2 These may be the same or different.

[0063] R of this constituent unit 1The polymerizable functional group may be a monovalent organic group having a reactive group (polymerizable functional group). Examples of polymerizable functional groups include those that can be thermoset or photocured. There are no particular limitations on polymerizable functional groups, but examples include vinyl groups, allyl groups, styryl groups, methacryloyl groups, acryloyl groups, acryloyloxy groups, methacryloyloxy groups, α-methylstyryl groups, vinyl ether groups, vinyl ester groups, acrylamide groups, methacrylamide groups, N-vinylamide groups, maleic acid ester groups, fumaric acid ester groups, N-substituted maleimide groups, isocyanate groups, oxetanyl groups, and epoxy groups. Among these, polymerizable functional groups having any of (meth)acryloyl groups, oxetanyl groups, and epoxy groups are preferred. The polymerizable functional group may further be substituted with a halogen atom, a hydroxyl group, an alkoxy group, an aryloxy group, an aralkyloxy group, or an oxy group.

[0064] As polymerizable functional groups having a (meth)acryloyl group, for example, groups represented by the following formula or groups containing this group are preferred.

[0065] [ka]

[0066] In the above formula, R 4 R represents a hydrogen atom or a methyl group. 5 R represents an alkylene group with 1 to 10 carbon atoms. 4 As such, an alkylene group having 2 to 10 carbon atoms is preferred.

[0067] The oxetanyl group is not particularly limited, but examples include the (3-ethyl-3-oxetanyl)methyloxy group and the (3-ethyl-3-oxetanyl)oxy group. The polymerizable functional group having an oxetanyl group is preferably the group represented by the following formula, or a group containing this formula.

[0068] [ka]

[0069] In the above formula, R 6 R represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. 7 R represents an alkylene group with 1 to 6 carbon atoms. 6 The hydrogen atom, methyl group, ethyl group, etc. are preferred, and the ethyl group is more preferred. 7 Preferably, the alkylene group has 2 to 6 carbon atoms, and a propylene group is more preferable.

[0070] Polymerizable functional groups having epoxy groups are not particularly limited, but examples include alkyl groups having 1 to 10 carbon atoms substituted with glycidoxy groups such as β-glycidoxyethyl, γ-glycidoxypropyl, and γ-glycidoxybutyl; and alkyl groups having 5 to 10 carbon atoms substituted with oxirane groups such as glycidyl, β-(3,4-epoxycyclohexyl)ethyl, γ-(3,4-epoxycyclohexyl)propyl, β-(3,4-epoxycycloheptyl)ethyl, 4-(3,4-epoxycyclohexyl)butyl, and 5-(3,4-epoxycyclohexyl)pentyl.

[0071] Polymerizable functional groups may be functional groups having a carbon-carbon double bond or a carbon-carbon triple bond that can undergo a hydrosilylation reaction with a hydrogen atom bonded to a silicon atom (hydrosilyl group). Unsaturated organic groups can also function as polymerizable functional groups in the sense that, due to the presence of a hydrogen atom in the hydrosilyl group, they polymerize with that hydrogen atom through a hydrosilylation reaction to form a hydrosilylated structural portion. Specific examples of such unsaturated organic groups include the alkenyl group and alkynyl group mentioned above. While not particularly limited, examples of unsaturated organic groups include vinyl group, orthostyryl group, metastyryl group, parastyryl group, acryloyl group, methacryloyl group, acryloxy group, methacryloxy group, 1-propenyl group, 1-butenyl group, 1-pentenyl group, 3-methyl-1-butenyl group, phenylethenyl group, ethynyl group, 1-propynyl group, 1-butynyl group, 1-pentynyl group, 3-methyl-1-butynyl group, phenylbutynyl group, allyl(2-propenyl) group, and octenyl(7-octen-1-yl) group. Such unsaturated organic groups are preferably any of vinyl group, parastyryl group, allyl(2-propenyl) group, and octenyl(7-octen-1-yl) group, with vinyl group being more preferred.

[0072] Furthermore, the compound represented by Formula 1 may contain two or more polymerizable functional groups. In this case, all polymerizable functional groups may be identical or different. Also, multiple polymerizable functional groups may be identical, and other different polymerizable functional groups may be included.

[0073] R 1 The alkyl groups, alkenyl groups, and alkynyl groups represented by these terms are aralkyl groups, aryl groups, and -C(=O)-CR groups. 33. Both the polymerizable functional group and the 3. polymerizable functional group may have substituents. Such substituents include halogen atoms such as fluorine, chlorine, bromine, and chlorine atoms; alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, s-butyl, isobutyl, t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, and isooctyl groups; hydroxyl groups; alkoxy groups; aryloxy groups; aralkyloxy groups; oxy groups (=O); cyano groups; and protected hydroxyl groups, at least one of these.

[0074] The protecting group of a protected hydroxyl group is not particularly limited, and known hydroxyl protecting groups can be used. For example, such protecting groups include acyl protecting groups represented by -C(=O)R (wherein R is an alkyl group having 1 to 6 carbon atoms, such as a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, and n-pentyl group; or a phenyl group with or without a substituent. The substituents of a phenyl group with a substituent include alkyl groups such as a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, s-butyl group, isobutyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, and isooctyl group; and fluorine atoms, chlorine atoms, and bromine atoms. Examples of protecting groups include rogen atoms (such as alkoxy groups like methoxy and ethoxy groups), silyl protecting groups such as trimethylsilyl, triethylsilyl, t-butyldimethylsilyl, and t-butyldiphenylsilyl groups; acetal protecting groups such as methoxymethyl, methoxyethoxymethyl, 1-ethoxyethyl, tetrahydropyran-2-yl, and tetrahydrofuran-2-yl groups; alkoxycarbonyl protecting groups such as t-butoxycarbonyl groups; and ether protecting groups such as methyl, ethyl, t-butyl, octyl, allyl, triphenylmethyl, benzyl, p-methoxybenzyl, fluorenyl, trityl, and benzhydryl groups.

[0075] The compound represented by Formula 1 comprises one or more of these constituent units in combination. The compound represented by Formula 1 comprises at least some of these constituent units, for example, three R 1 Preferably, all of them are alkyl groups, and for example, all of the constituent units have three R 1 It is preferable that all of them are alkyl groups.

[0076] The value of a, which is the ratio of moles of the constituent unit in the compound represented by Formula 1, is a positive number between 0 and 1. The lower limit of a is not particularly limited, but for example, it is preferably 0.25 or higher, more preferably 0.3 or higher, and even more preferably 0.35 or higher. The lower limit of a may also be 0.4 or higher. The upper limit of a is not particularly limited, but for example, it is preferably 0.5 or lower, and more preferably 0.45 or lower.

[0077] -Component Unit 2- Constituent unit 2 (that is, "R 1 2SiO 2 / 2 The R of the constituent unit represented by " 1 This includes hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, aralkyl groups, and -C(=O)-CR groups. 3 3. At least one selected from the group consisting of polymerizable functional groups. 1 They may be the same or they may be different.

[0078] Alkyl group, alkenyl group, alkynyl group, aryl group, aralkyl group, -C(=O)-CR 3 3. With respect to polymerizable functional groups, the various embodiments described for constituent unit 1 also apply to this constituent unit.

[0079] The compound represented by Formula 1 comprises one or more of these constituent units in combination. The compound represented by Formula 1 comprises at least some of these constituent units, for example, two R 1 Preferably, all of them are alkyl groups, and for example, all of the constituent units are two R 1 It is preferable that all of them are alkyl groups.

[0080] The ratio of moles of this constituent unit in the compound represented by Formula 1, b, is a positive number between 0 and 1. The lower limit of b is not particularly limited, but for example, 0.25 or higher is preferred, 0.3 or higher is more preferred, and 0.35 or higher is even more preferred. The lower limit of b may also be 0.4 or higher. The lower limit of b is not particularly limited, but for example, 0.5 or lower is preferred, and 0.45 or lower is more preferred.

[0081] -Component Unit 3- Constituent unit 3 (that is, "R 1 SiO 3 / 2 The R of the constituent unit represented by " 1 This includes hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, aryl groups, and -C(=O)-CR groups. 3 3. At least one selected from the group consisting of a monovalent organic group having a reactive group (polymerizable functional group). R in this constituent unit 1 They may be the same or they may be different.

[0082] Alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group, -C(=O)-CR 3 3. With respect to polymerizable functional groups, the various embodiments described for constituent unit 1 also apply to this constituent unit.

[0083] The compound represented by Formula 1 comprises one or more of these constituent units in combination. For example, one of these constituent units R 1 Using as an alkyl group, the R of the other constituent unit 1 The polymerizable functional group may also be R of one of the constituent units. 1 Let this be a hydrogen atom, and the other one constituent unit be R 1 This may be an unsaturated organic group used as a polymerizable functional group.

[0084] c, which is the ratio of moles of the constituent unit in the compound represented by Formula 1, is a positive number between 0 and 1. c is not particularly limited, but for example, it is preferably between 0.25 and 1, more preferably between 0.3 and 1, even more preferably between 0.35 and 1, and particularly preferably between 0.4 and 1. c may also be 0.5 or higher, 0.6 or higher, 0.7 or higher, 0.8 or higher, 0.9 or higher, 0.95 or higher, 0.99 or higher, or even 1.

[0085] -Component Unit 4- Constituent unit 4 (i.e., "SiO 4 / 2 The constituent unit represented by '' has a polysiloxane main skeleton. The proportion of this constituent unit in the compound represented by Formula 1 is not particularly limited.

[0086] The ratio of moles of this constituent unit in the compound represented by Formula 1, d, is a positive number between 0.00 and 1.00. The lower limit of d is not particularly limited, but for example, 0.25 or higher is preferred, 0.30 or higher is more preferred, and 0.35 or higher is even more preferred. The lower limit of d may also be 0.40 or higher. The upper limit of d is not particularly limited, but for example, 0.90 or lower is preferred.

[0087] -Component Unit 5- 5 constituent units (i.e., "R 2 O 1 / 2 The constituent unit represented by "" defines a unit containing an alkoxy group or a hydroxyl group in the compound represented by Formula 1. That is, R in this constituent unit 2 The group is either a hydrogen atom or an alkyl group. The alkyl group may be either an aliphatic group or an alicyclic group, and may be either linear or branched. Preferably, the alkyl group has 1 to 10 carbon atoms. Specific examples of alkyl groups with 1 to 10 carbon atoms include methyl, ethyl, n-propyl, isopropyl, butyl, pentyl, and hexyl groups.

[0088] The alkoxy group in this structural unit may, for example, be one that remains in the molecule during the synthesis process of the compound represented by Formula 1. Furthermore, the hydroxyl group in this structural unit may be a hydroxyl group that remains in the molecule after hydrolysis of the "alkoxy group" without polycondensation.

[0089] The value e, which represents the mole ratio of the constituent unit in the compound represented by Formula 1, is a positive number between 0.00 and 1.00. The lower limit of e is not particularly limited, but for example, it is preferably 0.20 or higher, more preferably 0.25 or higher, and even more preferably 0.30 or higher. The lower limit of e may also be 0.40 or higher. The upper limit of e is not particularly limited, but for example, it is preferably 0.90 or lower.

[0090] The compound represented by formula 1 preferably comprises one or more components selected from the group consisting of component 1, component 2, and component 4. That is, in formula 1, it is preferable that one or more of a, b, and d are positive numbers of 0 or greater.

[0091] The silsesquioxane compound may be in particulate form or non-particulate form such as a binder resin. If the silsesquioxane compound is in particulate form, the particles may be resin particles consisting solely of the silsesquioxane compound (hereinafter also simply referred to as "silsesquioxane resin particles"), or they may be resin particles formed by mixing the silsesquioxane compound with other resin components.

[0092] The volume-average particle size of the silsesquioxane resin particles is preferably, for example, 0.01 μm or more and 10.00 μm or less, more preferably 0.10 μm or more and 5.00 μm or less, and even more preferably 0.20 μm or more and 3.00 μm or less. When the volume-average particle size of the silsesquioxane resin particles is 0.01 μm or larger, they are more easily dispersed uniformly in the surface layer, making it easier to keep the dynamic friction coefficient μ1 of the surface layer of the pressure belt within the aforementioned range, resulting in superior surface layer slipperiness and further suppression of both image misalignment due to paper slippage on the fixing surface and paper wrinkling. When the volume-average particle size of the silsesquioxane resin particles is 10.00 μm or less, the increase in surface roughness of the surface layer is suppressed, and the occurrence of paper wrinkles is further suppressed.

[0093] The method for measuring the average particle size of silsesquioxane resin particles is as follows: A sample is taken from the surface layer of the pressure belt to be measured. The sample should have a cross-section aligned with the thickness direction of the surface layer as the observation surface. The observation surface of the sample is observed using a scanning electron microscope, and an image is captured. In the image, the area of ​​each primary particle of silsesquioxane resin is measured by image analysis, and the equivalent circle diameter is calculated from this area value. This calculation of the equivalent circle diameter is performed for 100 silsesquioxane resin particles. The 50th percentile diameter (D50v) at the volume-based cumulative frequency of the obtained equivalent circle diameters is then defined as the volume-average particle size of the silsesquioxane resin particles.

[0094] When the silsesquioxane compound is in particulate form, the content of silsesquioxane resin particles is preferably 1.0% by mass or more and 20.0% by mass or less, more preferably 1.0% by mass or more and 17.5% by mass or less, and even more preferably 1.0% by mass or more and 15.0% by mass or less, relative to the surface layer. When the silsesquioxane resin particle content is 1.0% by mass or more, the surface layer exhibits superior slipperiness, and both image misalignment due to paper slippage on the fixing surface and paper wrinkles are more effectively suppressed. When the silsesquioxane resin particle content is 20.0% by mass or less, the increase in surface roughness of the surface layer is suppressed, and the occurrence of paper wrinkles is further suppressed.

[0095] When the silsesquioxane compound is in the form of a binder resin or the like, the content of the silsesquioxane compound is preferably 50.0% by mass or more and 100.0% by mass or less, more preferably 75.0% by mass or more and 100.0% by mass or less, and even more preferably 80.0% by mass or more and 100.0% by mass or less, relative to the surface layer. When the silsesquioxane resin particle content is 50.0% by mass or more, the surface layer exhibits superior slipperiness, and both image misalignment due to paper slippage on the fixing surface and paper wrinkles are more effectively suppressed.

[0096] The content of the compound represented by formula 1 in the total silsesquioxane compound is preferably 80.0% by mass or more and 100.0% by mass or less, more preferably 90.0% by mass or more and 100.0% by mass or less, and even more preferably 95.0% by mass or more and 100.0% by mass or less.

[0097] • Surface layer characteristics The surface layer is a cured product of a composition containing the compound represented by Formula 1. The surface layer may be a cured product of a composition containing only the compound represented by Formula 1 (however, additives such as curing agents may be included) and no other resins, or it may be a cured product of a composition which is a mixture of another resin and the silsesquioxane compound. When the composition is a mixture of another resin and the silsesquioxane compound, the other resin is preferably a so-called binder resin.

[0098] When the composition is a mixture of another resin and a silsesquioxane compound, the silsesquioxane compound is preferably a liquid compound or a particulate compound. Examples of other resins included in the composition include polyimide resin (PI resin), polyamide-imide resin (PAI resin), polyetherketone resin (e.g., aromatic polyetheretherketone resin), polyphenylene sulfide resin (PPS resin), polyetherimide resin (PEI resin), polyester resin, polystyrene resin, polyamide resin, polycarbonate resin, silicone resin, and mixed resins thereof. Among the above, it is preferable to include a silicone resin as the other resin. Since silicone resin has bonding groups similar to those of siloxane compounds, it has excellent affinity for siloxane compounds. Therefore, the siloxane compound is strongly bonded to the silicone resin in the surface layer, making it difficult for the siloxane compound to detach from the surface layer. As a result, both image misalignment due to paper slip on the fixing surface and paper wrinkles are further suppressed.

[0099] The surface layer preferably contains 20% by mass or less of fluororesin relative to the surface layer, more preferably 10% by mass or less, and even more preferably 5% by mass or less. The fluororesin content may also be 0% by mass. When the fluororesin content is 20% by mass or less, the dynamic friction coefficient μ2 and Δ(μ1-μ2) values ​​with respect to the outer surface of the pressure belt can be easily adjusted to the aforementioned range. Furthermore, this is preferable from the viewpoint of environmentally friendly manufacturing.

[0100] The surface layer of the pressure belt preferably has a tensile modulus of 100 MPa or more at 150°C, more preferably 1000 MPa to 3500 MPa, and even more preferably 1500 MPa to 3000 MPa. If the tensile modulus of elasticity of the surface layer of the pressure belt at 150°C is 100 MPa or higher, the slipperiness of the surface layer is superior, and both image misalignment due to paper slippage on the fixing surface and paper wrinkles are more suppressed. If the tensile modulus of elasticity of the surface layer of the pressure belt at 150°C is 3500 MPa or less, the rebound of the surface layer of the pressure belt against the paper is suppressed, and the occurrence of paper wrinkles is further suppressed.

[0101] The method for achieving the above range of tensile modulus at 150°C is not particularly limited, but one example is a method in which the surface layer of the pressure belt is a cured film of a composition containing a compound represented by formula 1 and / or a silsesquioxane compound.

[0102] The tensile modulus value at 150°C was measured using the tensile property test method specified in JIS K7127 (1999).

[0103] The surface layer of the pressure belt preferably has a surface roughness Ra of 0.90 μm or less, more preferably 0.05 μm to 0.80 μm, and even more preferably 0.05 μm to 0.70 μm. When the surface roughness Ra of the pressure belt's surface layer is less than 1.0 μm, the surface layer exhibits superior slipperiness, further suppressing both image misalignment due to paper slippage on the fixing surface and paper wrinkling.

[0104] The method for achieving the surface roughness Ra of the surface layer of the pressure belt within the above range is not particularly limited, but one example is a method in which the surface layer of the pressure belt is made into a cured film of a composition containing a compound represented by formula 1 and / or a silsesquioxane compound.

[0105] The method for measuring the surface roughness Ra of the surface layer of the pressure belt is as follows. A sample is obtained by cutting out a portion of the surface layer of the pressure belt using a cutter or similar tool. This sample is then measured using a stylus-type surface roughness analyzer (e.g., Surfcom 1400A, manufactured by Tokyo Seimitsu Co., Ltd.). The measurement conditions are in accordance with JIS B0601-1994, with an evaluation length Ln = 2.5 mm, a reference length L = 0.8 mm, and a cutoff value of 0.008 mm.

[0106] The thickness of the surface layer is preferably, for example, 5 μm to 100 μm, and more preferably 10 μm to 30 μm.

[0107] • Method for forming a surface layer The method for forming the surface layer is not particularly limited, and conventional methods can be applied. If the surface layer is a cured product of a composition containing only a silsesquioxane compound and no other resins, for example, the surface layer may be formed on the substrate by immersing a cylindrical mold on which the base material of the fixing belt member is installed in a solution of the composition containing a silsesquioxane compound, and curing the coating film (for example, by irradiating it with ultraviolet light).

[0108] If the surface layer is a cured product of a composition containing another liquid resin and a particulate silsesquioxane compound, for example, a particulate silsesquioxane compound may be added to another liquid resin, such as a silicone resin solution, and stirred to obtain a mixed solution. Using this mixed solution, a cylindrical mold on which the base material of the fixing belt member is installed may be immersed in the mixed solution to coat and cure the mixture, thereby forming a surface layer on the base material.

[0109] (Resin base layer) Examples of resins included in the resin substrate layer include polyimide resin, polyamide-imide resin, polyetheretherketone resin, polyphenylene sulfide resin, polyethersulfone resin, polysulfone resin, and polyphenylsulfone resin. The resin may be used alone or in combination of two or more types. Among these, it is preferable that the resin includes polyimide resin.

[0110] Examples of polyimide resins include imidized polyamic acid (a precursor of polyimide resin), which is a polymer of tetracarboxylic dianhydride and a diamine compound. Examples of polyimide resins include resins having constituent units represented by the following general formula (I).

[0111] [ka]

[0112] In general formula (I), R 1 represents a tetravalent organic group, R 2 This represents a divalent organic group. R 1 Examples of tetravalent organic groups represented by include aromatic groups, aliphatic groups, cyclic aliphatic groups, groups combining aromatic and aliphatic groups, or groups in which these are substituted. Specific examples of tetravalent organic groups include residues of tetracarboxylic dianhydrides, which will be discussed later. R 2Examples of divalent organic groups represented by include aromatic groups, aliphatic groups, cyclic aliphatic groups, groups combining aromatic and aliphatic groups, or groups in which these are substituted. Specific examples of divalent organic groups include residues of diamine compounds, which will be discussed later.

[0113] Specific examples of tetracarboxylic dianhydrides used as raw materials for polyimide resins include pyromellitic acid dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3,3',4-biphenyltetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 1,2,5,6-naphthalene tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,2'-bis(3,4-dicarboxyphenyl)sulfonic acid dianhydride, perylene-3,4,9,10-tetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl) ether dianhydride, and ethylene tetracarboxylic dianhydride.

[0114] Specific examples of diamine compounds used as raw materials for polyimide resins include 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,3'-dichlorobenzidine, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfone, 1,5-diaminonaphthalene, m-phenylenediamine, p-phenylenediamine, 3,3'-dimethyl-4,4'-biphenyldiamine, benzidine, and 3,3'-dimethyl Benzidine, 3,3'-dimethoxybenzidine, 4,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylpropane, 2,4-bis(β-aminoteric)toluene, bis(p-β-aminoteric)butylphenyl)ether, bis(p-β-methyl-δ-aminophenyl)benzene, bis-p-(1,1-dimethyl-5-aminopentyl)benzene, 1-isopropyl-2,4-m-phenylenediamine, m-xylylenediamine, p-xylylenediamine, di(p -Aminocyclohexyl)methane, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, diaminopropyltetradiamine, 3-methylheptamethylenediamine, 4,4-dimethylheptamethylenediamine, 2,11-diaminododecane, 1,2-bis-3-aminopropoxyethane, 2,2-dimethylpropylenediamine, 3-methoxyhexamethylenediamine, 2,5-dimethylheptamethylenediamine, Examples include 3-methylheptamethylenediamine, 5-methylnonameethylenediamine, 2,17-diaminoeicosadecane, 1,4-diaminocyclohexane, 1,10-diamino-1,10-dimethyldecane, 12-diaminooctadecane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, piperazine, H2N(CH2)3O(CH2)2O(CH2)NH2, H2N(CH2)3S(CH2)3NH2, H2N(CH2)3N(CH3)2(CH2)3NH2, etc.

[0115] Examples of polyamide-imide resins include resins having imide bonds and amide bonds in their repeating units. More specifically, polyamide-imide resins include polymers of a trivalent carboxylic acid compound (also called tricarboxylic acid) having an acid anhydride group and a diisocyanate compound or diamine compound.

[0116] As the tricarboxylic acid, trimellitic anhydride and its derivatives are preferred. In addition to tricarboxylic acids, tetracarboxylic dianhydrides, aliphatic dicarboxylic acids, aromatic dicarboxylic acids, etc. may be used in combination.

[0117] Examples of diisocyanate compounds include 3,3'-dimethylbiphenyl-4,4'-diisocyanate, 2,2'-dimethylbiphenyl-4,4'-diisocyanate, biphenyl-4,4'-diisocyanate, biphenyl-3,3'-diisocyanate, biphenyl-3,4'-diisocyanate, 3,3'-diethylbiphenyl-4,4'-diisocyanate, 2,2'-diethylbiphenyl-4,4'-diisocyanate, 3,3'-dimethoxybiphenyl-4,4'-diisocyanate, 2,2'-dimethoxybiphenyl-4,4'-diisocyanate, naphthalene-1,5-diisocyanate, and naphthalene-2,6-diisocyanate. Examples of diamine compounds include those having a structure similar to the isocyanates described above, but with an amino group instead of an isocyanate group. The resin substrate layer may contain other components in addition to the resin. Examples of other components include conductive materials, fillers to improve mechanical strength, antioxidants to prevent thermal degradation, surfactants, and heat-resistant anti-aging agents.

[0118] (Elastic layer) The elastic layer is composed of, for example, a heat-resistant elastic material. Examples of heat-resistant elastic materials include silicone rubber and fluororubber. Examples of silicone rubbers include RTV (Room Temperature Vulcanizing) silicone rubber, HTV (High Temperature Vulcanizing) silicone rubber, and liquid silicone rubber. Specifically, examples include polydimethyl silicone rubber, methyl vinyl silicone rubber, methylphenyl silicone rubber, and fluorosilicone rubber. Examples of fluororubbers include vinylidene fluoride rubber, tetrafluoroethylene / propylene rubber, tetrafluoroethylene / perfluoromethyl vinyl ether rubber, phosphophazene rubber, and fluoropolyether.

[0119] The elastic layer may contain other components. Examples of other components include fillers, conductive materials, softeners (paraffin-based, etc.), processing aids (stearic acid, etc.), antioxidants (amine-based, etc.), vulcanizing agents (sulfur, metal oxides, peroxides, etc.), and functional fillers (alumina, etc.).

[0120] [Heating Roll 30] The heating roll 30 is constructed, for example, by sequentially forming an elastic layer 30b and a release layer 30c on a hollow metal core 30a, which has a heating source 31 such as a halogen lamp inside.

[0121] The metal core 30a is composed of a cylindrical metal body such as aluminum or stainless steel. The elastic layer 30b is composed of a thickness of approximately 2 mm to 5 mm of material such as HTV silicone rubber or fluororubber (rubber hardness of approximately 45 degrees according to JIS-A, measured using a spring-type A hardness tester manufactured by Teclock, in accordance with JIS K6301, with a load of 1,000 gf applied). The release layer 30c is composed of a thickness of approximately 20 μm to 50 μm of material such as fluororubber, silicone rubber, or fluororesin. Of course, it is not limited to these materials, and may be composed of conventionally known materials.

[0122] The heating roll 30 is driven to rotate at a peripheral speed of, for example, 260 mm / sec, with the speed adjusted by the drive source. The outer diameter of the heating roll 30 is generally between 25 mm and 80 mm.

[0123] The surface temperature of the heating roll 30 is detected by a temperature sensor (not shown) in contact with the surface, and controlled by a control circuit (not shown) so that the surface temperature is, for example, 175°C.

[0124] [Pressure pad 50 (an example of a pressure component)] The pressing pad 50 has two pressing portions 51a and 51b of different hardnesses, aligned with the direction of travel of the recording medium P. The pressing portion 51a on the side where the recording medium P enters the pressing pad 50 is made of a rubber-like elastic material, and the pressing portion 51b on the side where the recording medium P is discharged is made of a hard pressure-applying material such as metal, so that the pressure in the contact area is higher on the side where the recording medium P is discharged than on the side where the recording medium P enters. The pressing portions 51a and 51b are supported by a holder 51c and press against the heating roll 30 from the inner circumferential surface of the pressure belt 40 via a sliding sheet 60 (an example of a sliding member).

[0125] [Sliding sheet 60 (an example of a sliding member)] The sliding sheet 60 may be composed of a single layer of resin substrate, or it may be composed of a laminate of the resin substrate layer constituting the sliding surface and other layers provided on the opposite side of the sliding surface of the resin substrate layer.

[0126] The sliding sheet 60 is constructed, for example, by including a heat-resistant thermoplastic resin in its sliding surface. Examples of heat-resistant thermoplastic resins include polyetheretherketone resin, polyphenylene sulfide resin, polyetherimide resin, polyphenylsulfone resin, polyethersulfone resin, polysulfone resin, and polyphenylsulfone resin.

[0127] Among these, as the heat-resistant thermoplastic resin, at least one resin selected from the group consisting of polyetheretherketone resin, polyphenylene sulfide resin, polyetherimide resin, and polyphenylsulfone resin is preferred, and at least one resin selected from the group consisting of polyetheretherketone resin and polyphenylene sulfide resin is more preferred. These resins (especially polyetheretherketone resins and polyphenylene sulfide resins) are preferred because they have high abrasion resistance, high toughness, and high modulus of elasticity.

[0128] The resin substrate layer constituting the sliding surface may contain other components in addition to the resin. Examples of other components include conductive materials, fillers for improving mechanical strength, antioxidants to prevent thermal degradation, surfactants, and heat-resistant anti-aging agents.

[0129] [Lubricant 62 (An example of a lubricant)] The lubricant 62 is interposed between the inner circumferential surface of the pressure belt and the sliding member. Examples of lubricants 62 include grease, silicone oils (e.g., dimethyl silicone oil, methylphenyl silicone oil, amino-modified silicone oil, carboxy-modified silicone oil, silanol-modified silicone oil, sulfonic acid-modified silicone oil, etc.), and fluorine oils (e.g., fluorosilicone oil, perfluoropolyether oil, etc.). Among these, from the viewpoint of setting the viscosity of the lubricant within the range described later, it is preferable that the lubricant contains silicone oil, and more preferably contains long-chain alkyl-modified silicone oil (e.g., with 3 or more carbon atoms).

[0130] Lubricant 62 may contain other components besides oil. Other components include grease (such as silicone grease), thermal conductive agents, antioxidants, surfactants, silicone particles, organometallic salts, hindered amines, and the like.

[0131] [Image forming operation of an image forming apparatus] The image forming operation of the image forming apparatus according to this embodiment will be described below. The image forming operation will be described using the operation of forming a yellow image in the first process cartridge 10Y as a representative example.

[0132] First, prior to the image formation operation, the surface of the photoreceptor 1Y is charged by the charging roller 2Y to a potential of, for example, -600V to -800V.

[0133] The photoreceptor 1Y is formed, for example, by laminating a photosensitive layer on a conductive substrate. This photosensitive layer, for example, is normally highly resistive, but when irradiated with a laser beam 3Y, the resistivity of the irradiated portion changes. Therefore, the laser beam 3Y is output to the surface of the charged photoreceptor 1Y via the exposure device 3 according to image data for yellow sent from a control unit (not shown). The laser beam 3Y irradiates the photosensitive layer on the surface of the photoreceptor 1Y, thereby forming an electrostatic latent image of the yellow printing pattern on the surface of the photoreceptor 1Y.

[0134] The electrostatic latent image formed on the photoreceptor 1Y in this manner is rotated to the development position as the photoreceptor 1Y moves. At this development position, the electrostatic latent image on the photoreceptor 1Y is converted into a visible image (toner image) by the developing device 4Y.

[0135] The developing unit 4Y contains, for example, a developer including yellow toner and a carrier. The yellow toner becomes triboelectrically charged by being agitated inside the developing unit 4Y and has a charge of the same polarity (negative polarity) as the static charge on the photoreceptor 1Y. As the surface of the photoreceptor 1Y passes through the developing unit 4Y, the yellow toner electrostatically adheres only to the discharged latent image area on the surface of the photoreceptor 1Y, and the latent image is developed by the yellow toner. The photoreceptor 1Y, on which the yellow toner image has formed, continues to move, and the toner image developed on the photoreceptor 1Y is transported to the primary transfer position.

[0136] When the yellow toner image on the photoreceptor 1Y is transported to the primary transfer position, a primary transfer bias is applied to the primary transfer roller 5Y, and an electrostatic force acts on the toner image from the photoreceptor 1Y toward the primary transfer roller 5Y, transferring the toner image on the photoreceptor 1Y onto the intermediate transfer belt 20. The transfer bias applied at this time has a polarity opposite to the toner's polarity (-) (+), and in the first process cartridge 10Y, for example, it is controlled to a constant current of about +10 μA by a control unit (not shown).

[0137] Similarly, the primary transfer bias applied to the primary transfer rollers 5M, 5C, and 5K from the second process cartridge 10M onward is controlled.

[0138] Thus, the intermediate transfer belt 20, on which the yellow toner image has been transferred in the first process cartridge 10Y, is sequentially transported through the second to fourth process cartridges 10M, 10C, and 10K, and the toner images of each color are similarly superimposed and transferred in multiple layers.

[0139] The intermediate transfer belt 20, on which toner images of all colors have been transferred in multiple layers through the first to fourth process cartridges, proceeds to a secondary transfer section, which consists of the intermediate transfer belt 20, a support roller 24 in contact with the inner circumferential surface of the intermediate transfer belt 20, and a secondary transfer roller (an example of a secondary transfer device) 26 positioned on the image-holding surface side of the intermediate transfer belt 20. Meanwhile, the recording medium P is fed between the secondary transfer roller 26 and the intermediate transfer belt 20 via a supply mechanism, and a secondary transfer bias is applied to the support roller 24. The transfer bias applied at this time has the same polarity (-) as the polarity (-) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording medium P acts on the toner image, transferring the toner image on the intermediate transfer belt 20 onto the recording medium P. The secondary transfer bias at this time is determined according to the resistance detected by a resistance detection means (not shown) that detects the resistance of the secondary transfer section, and is controlled by a constant voltage. The intermediate transfer belt 20, primary transfer roller 5Y, and secondary transfer roller 26 are examples of a transfer device.

[0140] Next, the recording medium P is fed into the fuser 28 and inserted into a contact area formed by the pressure of a heating roll 30, which is rotated in the direction of the arrow, and a pressure belt 40. At this time, the recording medium P is inserted so that the surface of the recording medium P on which the unfixed toner image is formed faces the surface of the heating roll 30. When the recording medium P passes through this contact area, heat and pressure are applied to the recording medium P, fixing the unfixed toner image to the recording medium P. After fixing, the recording medium is peeled off from the heating roll 30 after passing through the contact area and discharged from the fuser 28.

[0141] In this manner, the fixing process is performed, and the image is permanently fixed onto the recording medium P. The recording medium P, on which the color image has been fixed, is then discharged towards the discharge section, and the series of color image formation operations is completed. [Examples]

[0142] Examples are described below, but the present invention is not limited to these examples. In the following description, unless otherwise specified, "parts" and "%" all refer to mass.

[0143] <Making a compression belt> • Preparation of pressure belts 1 and 6-8 A resin tubular body, while inserted and fixed in a metal cylindrical mold, was immersed in a solution of the type of silsesquioxane compound shown in Table 1 to form a surface coating, thereby obtaining a resin tubular body. Next, the resin tubular body, while inserted in the mold, was irradiated with ultraviolet light while rotating to cure the coating of the composition formed on the surface of the resin tubular body, thereby obtaining the pressure belts for each example. The ultraviolet irradiation conditions were as follows: ultraviolet light was emitted from a high-pressure mercury lamp (60 W / cm) from a distance of 300 mm from the resin tubular body for 10 minutes in an air atmosphere.

[0144] • Fabrication of pressure belts 5 and 10 A resin tubular body, while inserted and fixed in a metal cylindrical mold, was coated by immersion in a solution containing the types of silsesquioxane compounds shown in Table 1 and a silicone resin solution (KS700, manufactured by Shin-Etsu Chemical Co., Ltd.), thereby forming a surface coating. Next, the resin tubular body, while inserted in the mold, was heated and cured in a heating oven set to 280°C for 30 minutes.

[0145] • Preparation of pressure belts 2-4, 9, and 11-12 A resin tubular body, while inserted and fixed in a metal cylindrical mold, was coated by immersion in a solution containing the types of silsesquioxane compounds and resins shown in Table 1, thereby forming a surface coating. Next, the resin tubular body, while still inserted in the mold, was heated and cured in a heating oven set to 280°C for 30 minutes.

[0146] Table 1 shows the amount of silsesquioxane compound in the pressure belt for each example.

[0147] The abbreviations shown in Table 1 are as follows: -Silsesquioxane compounds- ·SQ1:[RSiO 1.5 ] n In the 3' component of the compound, R is a dimethylsilyloxy group, forming a silsesquioxane compound (PSS-Octakis(dimethylsilyloxy) substituted). • SQ2: Cage-type silsesquioxane compound having an oxetanyl group (manufactured by Toagosei Co., Ltd., OX-SQ SI-20) • SQ3: Cage-type silsesquioxane compound having a methacryloyl group (manufactured by Toagosei Co., Ltd., MAC-SQ TM-100) • SQ4: Cage-type silsesquioxane compound having an oxetanyl group (manufactured by Toagosei Co., Ltd., OX-SQ TX-100) • SQ5: Silsesquioxane compound having an acryloyl group (manufactured by Toagosei Co., Ltd., AC-SQ TA-100)

[0148] • Preparation of pressure belt C1 for Comparative Example 1 A silicone-based release agent was applied to the surface of an aluminum cylindrical core, which had an uneven surface created by shot blasting. After baking at 300°C for 1 hour, the surface was dipped with a varnish made by dissolving polyimide resin in N-methylpyrrolidone and dried at 120°C for 1 hour. This formed a resin substrate layer that constitutes the inner circumferential surface of the pressure belt. Next, a fluororesin dispersion (specifically, a PTFE dispersion) was coated onto the outer surface of the resin substrate layer. Then, it was dried in a firing furnace at 60°C for 10 minutes, gradually heated to 320°C, fired for 20 minutes, and then cooled to room temperature to form the surface layer. Subsequently, the resin substrate layer with the formed surface layer was removed from the core, cut to the desired size using a cutting machine, and a pressure belt was obtained.

[0149] • Preparation of pressure belt C2 for comparative example 2 In the preparation of the pressure belt for Comparative Example 1, a pressure belt was obtained with the same specifications as the pressure belt C1 for Comparative Example 1, except that a polycarbonate resin was coated on the outer surface of the resin substrate layer instead of a fluororesin dispersion (specifically, a PTFE dispersion).

[0150] The silsesquioxane compounds SQ1 to SQ7 all correspond to the compounds represented by Formula 1.

[0151] The abbreviations used in Table 1 are explained below. • PC resin: Polycarbonate resin • PI resin: Polyimide resin • Ur resin: Urethane resin, Superflex 420 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.: Urethane resin dispersion aqueous solution. A predetermined amount of silcecioxane was added to this urethane resin dispersion aqueous solution and stirred and mixed. The coating method was the method described above, and the solution was applied to the surface layer to form a tubular body.

[0152] In Table 1, the "sign" indicates which of μ1 and μ2 is the larger value. In Table 1, "μ1" refers to the coefficient of dynamic friction between the surface of the heating roll and the surface of the paper on which the toner image is fixed. In Table 1, "μ²" refers to the coefficient of dynamic friction between the back surface of the paper and the outer surface of the pressure belt. In Table 1, "Δ(μ1-μ2)" refers to the difference between the kinetic friction coefficients μ1 and μ2. In Table 1, the "150°C modulus of elasticity" in the [Surface layer of the pressure belt] column refers to the tensile modulus of elasticity at 150°C. In Table 1, the "150°C modulus of elasticity" in the [Surface layer of the heated roll] column refers to the tensile modulus of elasticity at 150°C.

[0153] <Preparation of heating rolls 1-5> An elastic layer made of silicone rubber was formed on the surface of an aluminum metal substrate roll by a mold injection molding method, and a metal roll with the elastic layer was obtained by heat vulcanization molding at 180°C. A silane coupling agent adhesive was spray-applied to the surface of the roll, and after drying, a tube made of tetrafluoroethylene perfluoroalkyl vinyl ether copolymer (PFA resin) (hereinafter also referred to as a PFA tube) was used to cover it and obtain a PFA-coated heated roll. Although heating rolls 1-5 use the same PFA tubing as described above, the tensile modulus of the surface layer of the heating rolls at 150°C was adjusted by modifying the manufacturing factors so that it matches the value in Table 1.

[0154] <Fabrication of fixing apparatus and image forming apparatus; Examples 1-12, Comparative Examples 1-2> The pressure belts and heating rolls of the types shown in Table 1 were mounted on the fixing unit of a modified APEOS PORT Print C5570 image forming machine manufactured by Fujifilm Business Innovation Co., Ltd. This fixing unit has the configuration shown in Figure 1. This image forming machine also has the configuration shown in Figure 2.

[0155] <Rating> The paper wrinkles and image misalignment were evaluated as follows: Print output was performed with the short side direction of the A4 paper and the extending direction of the rotation axis of the heating roll being the same, and a solid image (black solid 100% density) was output on A3 paper every 100,000 sheets (100kPV). The evaluation of paper wrinkles and image misregistration during paper travel up to 1,500,000 sheets (1500kPV) was carried out according to the following criteria. - Evaluation criteria: Paper wrinkles - A: No deformation or wrinkles of the paper occurred even when outputting up to 1500kPV. B: Deformation and wrinkles of the paper occurred at over 1000kPV and up to 1500kPV. C: Deformation and wrinkles of the paper occurred at over 500kPV and up to 1000kPV. D: Deformation and wrinkles of the paper occurred at over 200kPV and up to 500kPV. E: Deformation and wrinkles of the paper occurred at 200kPV or less.

[0156] - Evaluation criteria: Image misregistration - A: No image misregistration occurred even when outputting up to 1500kPV. B: Image misregistration occurred at over 1000kPV and up to 1500kPV. C: Image misregistration occurred at over 500kPV and up to 1000kPV. D: Image misregistration occurred at over 200kPV and up to 500kPV. E: Image misregistration occurred at 200kPV or less.

[0157]

Table 1

[0158] From the above results, it was found that the fixing device of this example suppresses both image misregistration and paper wrinkles due to paper slip on the fixing surface, compared with the fixing device of the comparative example.

[0159] This embodiment includes the following aspects. ((1)) A heating roll, A pressure belt provided in contact with the heating roll and having a surface layer that is a cured product of a composition containing a compound represented by the following formula 1 A pressing member disposed on the inner peripheral surface of the pressure belt and pressing the pressure belt from the inner peripheral surface of the pressure belt toward the heating roll A sliding member interposed between the inner peripheral surface of the pressure belt and the pressing member A lubricant interposed between the inner peripheral surface of the pressure belt and the sliding member A fixing device comprising (R 1 3SiO 1 / 2 ) a (R 1 2SiO 2 / 2 ) b (R 1 SiO 3 / 2 ) c (SiO 4 / 2 ) d (R 2 O 1 / 2 ) e Formula 1 (In Formula 1 R 1 represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an aryl group, a group represented by -C(=O)-CR 3 3, or a monovalent organic group having a reactive group. A plurality of R 1 ​​​​​​​​​​​​​​​​a, b, d, and e are each independently between 0 and 1, c is greater than 0 and less than or equal to 1, and a + b + c + d + e = 1. (((2))) The fixing apparatus according to (((1))), wherein the coefficient of dynamic friction μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the coefficient of dynamic friction μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1)))μ2. (((3))) The fixing device according to (((2))), wherein the difference Δμ(μ1-μ2) between the coefficient of dynamic friction μ1 and the coefficient of dynamic friction μ2 is 0.1 or more and 1.0 or less. (((4))) Heating roll and, A pressure belt comprising a surface layer which is a cured product of a composition containing a silsesquioxane compound and is disposed in contact with the aforementioned heating roll, A pressing member is disposed on the inner circumferential surface of the pressure belt and presses the pressure belt against the heating roll from the inner circumferential surface of the pressure belt, A sliding member interposed between the inner circumferential surface of the pressure belt and the pressing member, A lubricant interposed between the inner circumferential surface of the pressure belt and the sliding member, Equipped with, A fixing device in which the coefficient of dynamic friction μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the coefficient of dynamic friction μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1)))μ2. (((5))) The fixing device according to (((3))) or (((4))) above, wherein the difference Δμ(μ1-μ2) between the coefficient of dynamic friction μ1 and the coefficient of dynamic friction μ2 is 0.20 or more and 0.8 or less. (((6))) The fixing device according to (((5))), wherein the difference Δμ(μ1-μ2) between the coefficient of dynamic friction μ1 and the coefficient of dynamic friction μ2 is 0.30 or more and 0.60 or less. (((7))) The fixing device according to any one of the above (((2))) to (((6))), wherein the coefficient of dynamic friction μ1 is 0.4 or more and 0.9 or less. (((8))) The fixing device according to any one of the above (((2))) to (((7))), wherein the coefficient of dynamic friction μ2 is 0.1 or more and 0.7 or less. (((9))) The fixing apparatus according to any one of (((4))) to (((8))), wherein the silsesquioxane compound includes a compound represented by the following formula 1. (R 1 3SiO 1 / 2 ) a (R 1 2SiO 2 / 2 ) b (R 1 SiO 3 / 2 ) c (SiO 4 / 2 ) d (R 2 O 1 / 2 ) e formula 1 (In formula 1, R 1 This includes hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, aryl groups, and -C(=O)-CR groups. 3 Represents a group represented by 3, or a monovalent organic group having a reactive group. Multiple R 1 These may be the same or different. R 2 R represents a hydrogen atom or an alkyl group. Multiple R 2 These may be the same or different. R 3 R represents a hydrogen atom, a methyl group, or an ethyl group. Multiple R 3 These may be the same or different. The monovalent organic group may be substituted with a halogen atom, a hydroxyl group, an alkoxy group, an aryloxy group, an aralkyloxy group, or an oxy group. The alkyl group, alkenyl group, alkynyl group, aralkyl group, and aryl group may have substituents. a, b, d, and e are each independently between 0 and 1, c is greater than 0 and less than or equal to 1, and a + b + c + d + e = 1. (((10))) The fixing device according to any one of the above (((1))) to (((9))), wherein the surface layer of the pressure belt has a tensile modulus of 100 MPa or more at 150°C. (((11))) The fixing device according to any one of the above (((1))) to (((10))), wherein the surface layer of the pressure belt has a tensile modulus of elasticity of 1000 MPa or more and 3500 MPa or less at 150°C. (((12))) The fixing device according to any one of the above (((1))) to (((11))), wherein the surface layer of the pressure belt has a surface roughness Ra of 0.90 μm or less. (((13))) Image holder and, A charging device for charging the surface of the image holder, An electrostatic latent image forming apparatus for forming an electrostatic latent image on the surface of the charged image holder, A developing apparatus that contains a developer containing toner, and uses the developer to develop an electrostatic latent image formed on the surface of the image holder to form a toner image, A transfer device for transferring the toner image onto the surface of a recording medium, A fixing device according to any one of the above (((1))) to (((12))) for fixing the toner image onto the surface of a recording medium, An image forming apparatus equipped with the following features.

[0160] According to the invention of (((1))) or (((9))), a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the surface layer of the pressure belt is a fluororesin layer. According to the invention of (((2))), compared to the case where the dynamic friction coefficient μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the dynamic friction coefficient μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1 = μ2 or μ1 (((μ2), a fixing device is provided that suppresses both image misalignment due to paper slip on the fixing surface and paper wrinkles. According to the invention of (((3))), a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the value of the difference Δμ(μ1-μ2) between the dynamic friction coefficient μ1 and the dynamic friction coefficient μ2 is less than 0.1 or greater than 1.0. According to the invention of (((4))), compared to the case where the dynamic friction coefficient μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the dynamic friction coefficient μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1 = μ2 or μ1 (((μ2), a fixing device is provided that suppresses both image misalignment due to paper slip on the fixing surface and paper wrinkles. According to the invention of (((5))), a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the value of the difference Δμ(μ1-μ2) between the dynamic friction coefficient μ1 and the dynamic friction coefficient μ2 is less than 0.20 or greater than 0.80. According to the invention of (((6))), a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the value of the difference Δμ(μ1-μ2) between the dynamic friction coefficient μ1 and the dynamic friction coefficient μ2 is less than 0.30 or greater than 0.60. According to the invention of (((7))), a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the dynamic friction coefficient μ1 is less than 0.4 or greater than 0.9. According to the invention of (((8))), a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the dynamic friction coefficient μ2 is less than 0.1 or greater than 0.7. According to the invention of (((10))), a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the tensile modulus of elasticity of the surface layer of the pressure belt at 150°C is less than 100 MPa. According to the invention of (((11))), a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the tensile modulus of elasticity of the surface layer of the pressure belt at 150°C is less than 1000 MPa or more than 3500 MPa. According to the invention of (((12))), a fixing device is provided that suppresses both image misalignment due to paper slippage on the fixing surface and paper wrinkles, compared to the case where the surface roughness Ra of the surface layer of the pressure belt exceeds 0.90 μm. (((13))) According to the invention, compared with the case where "the surface layer of the pressure belt is a fluororesin layer" or "the dynamic friction coefficient μ1 between the surface of the heating roll and the surface of the toner image on the paper to be fixed, and the dynamic friction coefficient μ2 between the back surface of the paper and the outer peripheral surface of the pressure belt satisfy μ1 = μ2 or μ1(((μ2), a fixing device is provided that suppresses both image deviation and paper wrinkles due to paper slip on the fixing surface, compared with the case where the surface layer of the pressure belt is a fluororesin layer.

Explanation of Reference Signs

[0161] 1Y, 1M, 1C, 1K photoreceptor 2Y, 2M, 2C, 2K charging roller 3Y, 3M, 3C, 3K laser beam 3 exposure device 4Y, 4M, 4C, 4K developing device 5Y, 5M, 5C, 5K primary transfer roller 6Y, 6M, 6C, 6K photoreceptor cleaning device 10Y, 10M, 10C, 10K process cartridge 20 intermediate transfer belt 20a intermediate transfer body cleaning device 22 drive roller 24 support roller 26 secondary transfer roller 28 fixing device 30 heating roll 30a hollow core metal core 30a metal core 30b elastic body layer 30c release layer 31 heat source 40 pressure belt 50 pressing pad 51a pressing part 51b pressing part 51c holder 52 belt running guide 60 sliding sheet 62 lubricant <− 64 lubricant supply member 100 Image forming apparatus P recording medium

Claims

1. A heated roll and A pressure belt is disposed in contact with the aforementioned heating roll and has a surface layer which is a cured product of a composition containing a compound represented by the following formula 1, A pressing member is disposed on the inner circumferential surface of the pressure belt and presses the pressure belt against the heating roll from the inner circumferential surface of the pressure belt, A sliding member interposed between the inner circumferential surface of the pressure belt and the pressing member, A lubricant interposed between the inner circumferential surface of the pressure belt and the sliding member, A fixing device equipped with the following features. (R １ ３ SiO １／２ ) ａ (R １ ２ SiO ２／２ ) ｂ (R １ SiO ３／２ ) ｃ (SiO ４／２ ) ｄ (R ２ O １／２ ) ｅ Formula 1 (In formula 1, R １ This includes hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, aryl groups, and -C(=O)-CR ３ ３ This represents a group represented by or a monovalent organic group having a reactive group. Multiple R １ These may be the same or different. R ２ R represents a hydrogen atom or an alkyl group. Multiple R ２ These may be the same or different. R ３ R represents a hydrogen atom, a methyl group, or an ethyl group. Multiple R ３ These may be the same or different. The monovalent organic group may be substituted with a halogen atom, a hydroxyl group, an alkoxy group, an aryloxy group, an aralkyloxy group, or an oxy group. The alkyl group, alkenyl group, alkynyl group, aralkyl group, and aryl group may have substituents. a, b, d, and e are each independently between 0 and 1, c is greater than 0 and less than or equal to 1, and a + b + c + d + e = 1.

2. The fixing apparatus according to claim 1, wherein the coefficient of dynamic friction μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the coefficient of dynamic friction μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1 > μ2.

3. The fixing device according to claim 2, wherein the difference Δμ(μ1-μ2) between the dynamic friction coefficient μ1 and the dynamic friction coefficient μ2 is 0.10 or more and 1.00 or less.

4. A heated roll and A pressure belt comprising a surface layer which is a cured product of a composition containing a silsesquioxane compound and is disposed in contact with the aforementioned heating roll, A pressing member is disposed on the inner circumferential surface of the pressure belt and presses the pressure belt against the heating roll from the inner circumferential surface of the pressure belt, A sliding member interposed between the inner circumferential surface of the pressure belt and the pressing member, A lubricant interposed between the inner circumferential surface of the pressure belt and the sliding member, Equipped with, A fixing device in which the coefficient of dynamic friction μ1 between the surface of the heating roll and the surface of the paper on which the toner image is fixed, and the coefficient of dynamic friction μ2 between the back surface of the paper and the outer surface of the pressure belt satisfy the relationship μ1 > μ2.

5. The fixing device according to claim 3 or claim 4, wherein the difference Δμ(μ1-μ2) between the dynamic friction coefficient μ1 and the dynamic friction coefficient μ2 is 0.20 or more and 0.80 or less.

6. The fixing device according to claim 5, wherein the difference Δμ(μ1-μ2) between the dynamic friction coefficient μ1 and the dynamic friction coefficient μ2 is 0.30 or more and 0.60 or less.

7. The fixing device according to claim 2 or claim 4, wherein the coefficient of dynamic friction μ1 is 0.40 or more and 0.90 or less.

8. The fixing device according to claim 2 or claim 4, wherein the coefficient of dynamic friction μ2 is 0.10 or more and 0.70 or less.

9. The fixing apparatus according to claim 4, wherein the silsesquioxane compound comprises a compound represented by the following formula 1. (R １ ３ SiO １／２ ) ａ (R １ ２ SiO ２／２ ) ｂ (R １ SiO ３／２ ) ｃ (SiO ４／２ ) ｄ (R ２ O １／２ ) ｅ Formula 1 (In formula 1, R １ This includes hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, aryl groups, and -C(=O)-CR ３ ３ This represents a group represented by or a monovalent organic group having a reactive group. Multiple R １ These may be the same or different. R ２ R represents a hydrogen atom or an alkyl group. Multiple R ２ These may be the same or different. R ３ R represents a hydrogen atom, a methyl group, or an ethyl group. Multiple R ３ These may be the same or different. The monovalent organic group may be substituted with a halogen atom, a hydroxyl group, an alkoxy group, an aryloxy group, an aralkyloxy group, or an oxy group. The alkyl group, alkenyl group, alkynyl group, aralkyl group, and aryl group may have substituents. a, b, d, and e are each independently between 0 and 1, c is greater than 0 and less than or equal to 1, and a + b + c + d + e = 1.

10. The fixing device according to claim 1 or claim 4, wherein the surface layer of the pressure belt has a tensile modulus of elasticity of 100 MPa or more at 150°C.

11. The fixing device according to claim 1 or claim 4, wherein the surface layer of the pressure belt has a tensile modulus of elasticity of 1000 MPa or more and 3500 MPa or less at 150°C.

12. The fixing device according to claim 1 or claim 4, wherein the surface layer of the pressure belt has a surface roughness Ra of 0.90 μm or less.

13. Image holder and, A charging device for charging the surface of the image holder, An electrostatic latent image forming apparatus for forming an electrostatic latent image on the surface of the charged image holder, A developing apparatus that contains a developer containing toner, and uses the developer to develop an electrostatic latent image formed on the surface of the image holder to form a toner image, A transfer device for transferring the toner image onto the surface of a recording medium, A fixing apparatus according to claim 1 or claim 4 for fixing the toner image onto the surface of a recording medium, An image forming apparatus equipped with the following features.

Images