Image forming apparatus and image forming method

Abstract

To provide an image forming apparatus that can produce images with high brilliance when forming images using toner containing luminous toner particles. [Solution] An image forming apparatus comprising: a developing means for containing toner in which toner particles contain a metallic pigment with an average circular equivalent diameter of 5 μm or more and 15 μm or less, the average value of the ratio b / a of the major axis diameter a to the minor axis diameter b in the cross-section of the toner particles is 0.5 or more and 0.8 or less, and the average value of the area of ​​the metallic pigment in the projected image of the toner particles is 0.5 or more and 0.7 or less; and a fixing device comprising a fixing member having a surface layer which is a cured product of a composition in which the ratio (T-type / D-type) of organopolysiloxane (T-type) and dimethylorganopolysiloxane (D-type) is 1 / 9 or more and 9 / 1 or less, and the difference ΔH between the maximum and minimum values ​​of ultramicrohardness when the ultramicrohardness is measured at any 50 points is 0 or more and 15 or less.

Description

[Technical Field]

[0001] This disclosure relates to an image forming apparatus and an image forming method. [Background technology]

[0002] In electrophotographic image forming apparatuses, an image is formed by bringing a fixing member into contact with a toner image transferred onto a recording medium, applying heat and pressure, and fixing the toner image to the recording medium.

[0003] For example, Patent Document 1 discloses a heat fixing roll in which at least the surface layer is made of silicone rubber cured from a polyorganosiloxane composition that basically consists of (A) polyorganosiloxane, (B) a curing agent, and (C) polymethylsilsesquioxane. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 158362 / 1983 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] The object of this disclosure is to provide an image forming apparatus and an image forming method that can produce images with high brilliance when forming images using toner containing brilliance toner particles, compared to an image forming apparatus equipped with a fixing member having a surface layer which is a cured product of a composition with a content ratio (T-type / D-type) of less than 1 / 9 or greater than 9 / 1, or a surface layer in which the difference ΔH between the maximum and minimum values ​​of ultrafine hardness is greater than 15. [Means for solving the problem]

[0006] The means for solving the above problems include the following embodiments. <1> Image holder and, A charging means for charging the surface of the image holder, A means for forming an electrostatic image on the surface of the charged image holder, A developing means for developing an electrostatic image developer containing toner, wherein the toner particles contain a metallic pigment having an average equivalent circular diameter of 5 μm or more and 15 μm or less, the average value of the ratio b / a of the major axis diameter a to the minor axis diameter b in the cross-section of the toner particles is 0.5 or more and 0.8 or less, and the average value of the area of ​​the metallic pigment in the projected image of the toner particles when viewed from the thickness direction is 0.5 or more and 0.7 or less, and developing means for developing an electrostatic image formed on the surface of the image holder as a toner image using the electrostatic image developer, A transfer means for transferring the aforementioned toner image to a recording medium, A fixing device comprising a fixing member having a surface layer having a surface layer in which the difference ΔH between the maximum and minimum ultramicrohardness values ​​when ultramicrohardness is measured at 50 arbitrary points according to the ultramicrohardness test specified in JIS Z2255 (2003), is 0 or more and 15 or less, and the surface layer of the fixing member is brought into contact with the toner image on the recording medium and heated and pressurized to fix the toner image on the recording medium, and An image forming apparatus comprising: Equation 1 [R 1 SiO 3 / 2 ] m (In Equation 1, R 1 Each of these independently represents a hydrogen atom, alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group, and -C(=O)-CR 2 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, a methyl group, or an ethyl group. 2When there are a plurality of them, the plurality of Rs 2 may be the same as each other 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. m represents a positive integer.) <2> The image forming apparatus according to <1>, wherein the content ratio (T type / D type) in the composition is 3 / 7 or more and 7 / 3 or less. <3> The image forming apparatus according to <1> or <2>, wherein the difference ΔH between the maximum value and the minimum value of the ultra-micro hardness of the surface layer is 0 or more and 5 or less. <4> The image forming apparatus according to any one of <1> to <3>, wherein the surface layer has a tensile elongation rate of 100 or more. <5> The image forming apparatus according to <4>, wherein the surface layer has a tensile elongation rate of 150 or more. <6> The image forming apparatus according to any one of <1> to <5>, wherein the average value of the ratio B / A×100 (%) of the indentation amount B at the time of load release to the indentation amount A at the time of load application in the ultra-micro hardness test defined in JIS Z2255 (2003) for the surface layer is 45% or less. <7> The image forming apparatus according to <6>, wherein the average value of the ratio B / A×100 (%) is 40% or less. <8> The R 1 The image forming apparatus according to any one of <1> to <7>, wherein at least one of them is a methyl group or a phenyl group. <9> The R 1 The image forming apparatus according to <8>, wherein at least one of them is a methyl group. <10>​​​A step of forming an electrostatic image on the surface of the charged image holder, A developing step of developing an electrostatic image formed on the surface of an image holder as a toner image using an electrostatic image developer containing toner, wherein the toner particles contain a metal pigment having an average equivalent circular diameter of 5 μm or more and 15 μm or less, the average value of the ratio b / a of the major axis diameter a to the minor axis diameter b in the cross-section of the toner particles is 0.5 or more and 0.8 or less, and the average value of the area of ​​the metal pigment in the projected image of the toner particles when viewed from the thickness direction is 0.5 or more and 0.7 or less. A transfer step of transferring the toner image formed on the surface of the image holder to the surface of the recording medium, A fixing step in which a toner image is fixed to a recording medium by bringing the surface layer of a fixing member into contact with the toner image on the recording medium and applying heat and pressure, the fixing member having a surface layer having a surface layer having a surface layer where the difference ΔH between the maximum and minimum ultramicrohardness values ​​when the ultramicrohardness is measured at any 50 points according to the ultramicrohardness test specified in JIS Z2255 (2003) is 0 or more and 15 or less, and the surface layer of the fixing member is brought into contact with the toner image on the recording medium and the toner image is fixed to the recording medium, the fixing step is to fix the toner image to the recording medium, the fixing member having a surface layer having a surface layer where the difference ΔH between the maximum and minimum ultramicrohardness values ​​is 0 or more and 15 or less when the ultramicrohardness is measured at any 50 points according to the ultramicrohardness test specified in JIS Z2255 (2003), the surface layer of the fixing member is brought into contact with the toner image on the recording medium and the toner image is fixed to the recording medium, the fixing step is to fix the toner image to the recording medium, the fixing member having a surface layer having a surface layer having a surface layer where the difference ΔH between the maximum and minimum ultramicrohardness values ​​is 0 or more and 15 or less, the surface layer of the fixing member is brought into contact with the toner image on the recording medium, and the toner image is fixed to the recording medium, the fixing step is to fix the toner image to the recording medium, An image forming method having the following characteristics. Equation 1 [R 1 SiO 3 / 2 ] m (In Equation 1, R 1 Each of these independently represents a hydrogen atom, alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group, and -C(=O)-CR 2 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, a methyl group, or an ethyl group. 2 If you have multiple R 2These 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. m represents a positive integer. [Effects of the Invention]

[0007] <1> , <8> , or <9> According to the invention, compared to an image forming apparatus equipped with a fixing member having a surface layer which is a cured product of a composition with a content ratio (T-type / D-type) of less than 1 / 9 or greater than 9 / 1, or a surface layer in which the difference ΔH between the maximum and minimum values ​​of ultrafine hardness is greater than 15, an image forming apparatus is provided that can obtain an image with high brilliance when forming an image using a toner containing brilliance toner particles. <2> According to the invention, compared to an image forming apparatus equipped with a surface layer which is a cured product of a composition having a content ratio (T-type / D-type) of less than 3 / 7 or greater than 7 / 3, an image forming apparatus is provided that can obtain an image with high brilliance when forming an image using a toner containing brilliance toner particles. <3> According to the invention, compared to an image forming apparatus equipped with a fixing member having a surface layer in which the difference ΔH between the maximum and minimum values ​​of ultra-micro hardness is greater than 5, an image forming apparatus is provided that can obtain an image with high brilliance when forming an image using toner containing brilliance toner particles. <4> or <5> According to the invention, compared to an image forming apparatus equipped with a fixing member having a surface layer with a tensile elongation of less than 100, an image forming apparatus is provided that can obtain an image with high brilliance when forming an image using toner containing brilliance toner particles. <6> or <7> According to the invention, compared to an image forming apparatus equipped with a fixing member in which the average value of the surface layer ratio B / A × 100 (%) exceeds 45%, an image forming apparatus is provided that can stably obtain images with high brilliance when continuously forming images with brilliance. <10> According to the invention, compared to an image forming method in which the fixing process is performed using a fixing member having a surface layer which is a cured product of a composition with a content ratio (T-type / D-type) of less than 1 / 9 or greater than 9 / 1, or a surface layer in which the difference ΔH between the maximum and minimum values ​​of ultrafine hardness is greater than 15, an image forming method is provided in which an image can be formed using a toner containing lustrous toner particles and an image with high lustrousness is obtained. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic cross-sectional view showing an example of a fixing member used in this embodiment. [Figure 2] This is a schematic cross-sectional view showing an example of the layer structure of the electrophotographic photoreceptor used in this embodiment. [Figure 3] This is a schematic diagram showing an example of a first embodiment of the fixing device used in this embodiment. [Figure 4] This is a schematic diagram showing an example of a second embodiment of the fixing device used in this embodiment. [Figure 5] This is a schematic diagram showing an example of an image forming apparatus according to this embodiment. [Modes for carrying out the invention]

[0009] An example embodiment of this disclosure will be described. These descriptions and examples are illustrative and do not limit the scope of the invention. In this specification, a numerical range represented by "~" means a range that includes the numbers before and after "~" as lower and upper limits, unless those numbers are preceded by "greater than" or "less than". If the numbers before and after "~" are preceded by "greater than" or "less than", the numerical range means a range that does not include those numbers as lower or upper limits. In the numerical ranges described stepwise in this specification, the upper limit of one stepwise numerical range may be replaced with the upper limit of another stepwise numerical range, or with the values ​​shown in the examples. Similarly, the lower limit of one stepwise numerical range may be replaced with the lower limit of another stepwise numerical range, or with the values ​​shown in the examples. Furthermore, unless otherwise specified, the percentage (%) used for content refers to "mass%". A percentage of "0" indicates that the component is optional and does not need to be included.

[0010] 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. The term "process" includes not only independent processes, but also any process that cannot be clearly distinguished from other processes, as long as its intended function is achieved.

[0011] <Image forming apparatus> An image forming apparatus according to the embodiment of the present disclosure comprises: an image holder; charging means for charging the surface of the image holder; electrostatic image forming means for forming an electrostatic image on the charged surface of the image holder; developing means for containing an electrostatic image developer containing toner and developing the electrostatic image formed on the surface of the image holder as a toner image using the electrostatic image developer; transfer means for transferring the toner image to a recording medium; and fixing apparatus for fixing the toner image to a recording medium by bringing the surface layer of a fixing member into contact with the toner image on the recording medium and applying heat and pressure. Furthermore, toner contains toner particles. The toner particles contain a metallic pigment with an average equivalent circular diameter of 5 μm or more and 15 μm or less, the average value of the ratio b / a (major axis diameter a to minor axis diameter b) in the cross-section of the toner particle is 0.5 or more and 0.8 or less, and the average value of the area of ​​the metallic pigment in the projected image of the toner particle when viewed from the thickness direction is 0.5 or more and 0.7 or less. Hereinafter, toner particles that meet these requirements will be referred to as "lustrous toner particles". Furthermore, the surface layer of the fixing member is a cured product of a composition containing an organopolysiloxane (Type T) having a silsesquioxane structure represented by the following formula 1, and a dimethylorganopolysiloxane (Type D), wherein the content ratio of organopolysiloxane (Type T) to dimethylorganopolysiloxane (Type D) (Type T / Type D) is 1 / 9 or more and 9 / 1 or less. The surface layer has a difference ΔH between the maximum and minimum ultramicrohardness values ​​when measured at 50 arbitrary points using the ultramicrohardness test specified in JIS Z2255 (2003), which is 0 or more and 15 or less. Note that the content ratio (Type T / Type D) represents the mass ratio.

[0012] The image forming apparatus according to this embodiment, with the above configuration, can produce images with high brilliance. The reason for this is presumed to be as follows.

[0013] Conventionally, in image formation using toner, there has been a demand for forming images with a metallic luster (i.e., lustrousness). For this reason, electrostatic image developing toners containing metal pigments with a large equivalent circle diameter in the toner particles have been used. Specifically, a large equivalent circle diameter refers to an average equivalent circle diameter of 5 μm or more and 15 μm or less. In this embodiment, the average value of the ratio b / a and the average value of the area of ​​the metal pigment in the projected image of the toner particles when viewed from the thickness direction are within the aforementioned range. As a result, the shape of the lustrous toner particles becomes flattened, and an image with superior lustrousness is formed.

[0014] In image formation using lustrous toner particles, the flattened lustrous pigment is oriented along the planar direction of the recording medium by pressurizing and heating from a fixing member, thereby exhibiting a greater metallic luster. However, in order to orient the lustrous pigment along the planar direction, the lustrous toner particles are heated and melted to a higher temperature than when toner particles other than lustrous toner particles are used. Specifically, the lustrous toner particles are heated to a higher temperature by methods such as increasing the temperature of the fixing member in contact with the toner particles or reducing the process speed of the fixing device. On the other hand, the higher the temperature of the toner particles during fixing, the higher the release properties required from the fixing material. However, increasing the release properties of the fixing material reduces the amount of strain applied to the toner, and the effect of grinding the toner decreases. As a result, the luminous pigment becomes less likely to be oriented along the image, and conversely, the luminosity of the image may decrease.

[0015] In contrast, in the image forming apparatus according to this embodiment, the surface layer of the fixing member is formed by a cured product of a composition containing organopolysiloxane (Type T) having a silsesquioxane structure and dimethyl organopolysiloxane (Type D) in the aforementioned ratio. Therefore, while release properties from the toner are ensured in the surface layer, the flexibility of the surface layer is enhanced by the inclusion of dimethyl organopolysiloxane (Type D). As a result, sufficient pressure is applied from the fixing member to the luminous toner particles, causing the luminous pigment to orient along the planar direction of the recording medium, thereby enhancing the luminosity of the image.

[0016] The embodiments of this disclosure will be described in more detail below.

[0017] [Fixing member] The fixing device includes a fixing member. The fixing member has at least a surface layer and may further have a base material, and may have an elastic layer between the base material and the surface layer. The fixing member fixes the toner image to the recording medium by bringing the surface layer into contact with the toner image on the recording medium and applying heat and pressure. The shape of the fixing member may be, for example, belt-shaped.

[0018] (Surface layer) The surface layer of the fixing member does not contain fluorine atoms. "Does not contain fluorine atoms" means that it does not contain compounds that contain fluorine atoms (F) in their molecular structure. Examples of compounds that contain fluorine atoms (F) in their molecular structure include fluororesins such as tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), polytetrafluoroethylene (PTFE), tetrafluoroethylene / hexafluoropropylene copolymer (FEP), polyethylene-tetrafluoroethylene (ETFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), and vinyl fluoride (PVF).

[0019] The surface layer is a cured product of a composition (hereinafter also referred to as the "specified composition") containing an organopolysiloxane (Type T) having a silsesquioxane structure represented by the following formula 1, and a dimethylorganopolysiloxane (Type D). The content ratio (Type T / Type D) of organopolysiloxane (Type T) to dimethylorganopolysiloxane (Type D) in the specified composition is 1 / 9 or more and 9 / 1 or less.

[0020] • Organopolysiloxane (T-type) The following describes organopolysiloxanes (T-type) having a silsesquioxane structure represented by Formula 1 below. Equation 1 [R 1 SiO 3 / 2 ] m (In Equation 1, R 1 Each of these independently represents a hydrogen atom, alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group, and -C(=O)-CR 2 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, a methyl group, or an ethyl group. 2 If you have multiple R 2 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. m represents a positive integer.

[0021] Organopolysiloxane (T-type) has a silsesquioxane structure represented by formula 1 (i.e., "R" 1 SiO 3 / 2 It has only the constituent units represented by ".

[0022] R 1 This includes hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, aryl groups, and -C(=O)-CR groups. 2 At least one selected from the group consisting of the group represented by 3, or a monovalent organic group having a reactive group (hereinafter also referred to as a "polymerizable functional group"). If m is 2 or more, there are multiple R 1 They may be the same or they may be different.

[0023] R 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 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, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl groups.

[0024] R 1The 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, and octenyl (7-octen-1-yl) group.

[0025] R 1 The 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.

[0026] R 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.

[0027] R 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, and a 2-naphthyl group.

[0028] R 1 is -C(=O)-CR 2 3 is also acceptable. 2 R represents a hydrogen atom, a methyl group, or an ethyl group. 2It is preferable that it is a methyl group. 2 If you have multiple R 2 These may be the same or different.

[0029] R 1 The 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.

[0030] As polymerizable functional groups having a (meth)acryloyl group, for example, groups represented by the following formula or groups containing this group are preferred.

[0031] [ka]

[0032] 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.

[0033] 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.

[0034] [ka]

[0035] 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.

[0036] 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.

[0037] 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.

[0038] Furthermore, the organopolysiloxane (T-type) having the silsesquioxane structure 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 further different polymerizable functional groups may be included.

[0039] R 1 The alkyl groups, alkenyl groups, and alkynyl groups represented by these terms are aralkyl groups, aryl groups, and -C(=O)-CR groups. 23. 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.

[0040] 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.

[0041] In Equation 1, R 1Preferably, at least one of them is a methyl group or a phenyl group, and more preferably a methyl group.

[0042] The number of silsesquioxane structures represented by formula 1 (i.e., the number of m) in organopolysiloxanes (T-type) is a positive integer.

[0043] • Dimethylorganopolysiloxane (Type D) Dimethyl organopolysiloxane (Type D) has the structure represented by the following formula 2. Equation 2 [R 3 2SiO 2 / 2 ] n (In equation 2, R 3 Each of these independently represents a hydrogen atom, alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group, and -C(=O)-CR 2 Represents a group represented by 3, or a monovalent organic group having a reactive group. Multiple R 3 These may be the same or different. R 2 R represents a hydrogen atom, a methyl group, or an ethyl group. 2 If you have multiple R 2 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. n represents a positive integer.

[0044] Dimethylorganopolysiloxane (Type D) has a molecular structure represented by the structure shown in Equation 2 (i.e., "R 3 2SiO 2 / 2 It has only the constituent units represented by ".

[0045] R 3This includes hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aralkyl groups, aryl groups, and -C(=O)-CR groups. 2 At least one selected from the group consisting of the group represented by 3, or a monovalent organic group (polymerizable functional group) having a reactive group. If n is 2 or more, there are multiple R 3 They may be the same or they may be different.

[0046] Alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group, -C(=O)-CR 3 3. Regarding preferred embodiments of polymerizable functional groups, etc., the formula "R 1 The same configurations as those described in the various aspects of "[...]" can be cited.

[0047] The number of structures represented by formula 2 (i.e., the number of n) in dimethylorganopolysiloxane (type D) is a positive integer.

[0048] ·Content ratio (T type / D type) The content ratio (T-type / D-type) of organopolysiloxane (T-type) and dimethylorganopolysiloxane (D-type) contained in the specific composition is 1 / 9 or more and 9 / 1 or less. A content ratio (T-type / D-type) of 1 / 9 or more enhances the release properties from the toner on the surface layer. A content ratio (T-type / D-type) of 9 / 1 or less enhances the flexibility of the surface layer, allowing sufficient pressure to be applied from the fixing member to the luminous toner particles, causing the luminous pigment to orient along the planar direction of the recording medium and enhancing the luminosity of the image. From the viewpoint of further enhancing the luminosity of the image, a content ratio (T-type / D-type) of 3 / 7 or more and 7 / 3 or less is preferable.

[0049] This document describes a method for detecting the content ratio of organopolysiloxane (Type T) and dimethylorganopolysiloxane (Type D) in a specific composition from the surface layer, which is the cured product of the specific composition. The content ratio is calculated by measuring the content of organopolysiloxane (Type T) and dimethylorganopolysiloxane (Type D) in the surface layer by infrared absorption spectroscopy (IR) analysis.

[0050] • Surface layer: Other additives The surface layer may contain other additives besides organopolysiloxane (Type T) and dimethylorganopolysiloxane (Type D). Examples of other additives include conductive particles (e.g., carbon black), low-friction particles (e.g., graphite), molybdenum disulfide, and silica particles. The content of each additive can be, for example, 1% to 5% by mass for conductive particles, 1% to 10% by mass for low-friction particles, and 1% to 20% by mass for silica particles. When the surface layer contains other additives, the total amount of organopolysiloxane (Type T) and dimethylorganopolysiloxane (Type D) in the surface layer is preferably 60% by mass or more, and more preferably 80% by mass. The total amount of organopolysiloxane (Type T) and dimethylorganopolysiloxane (Type D) in the surface layer may be 100% by mass (i.e., without other additives).

[0051] • The difference between the maximum and minimum values ​​of ultramicrohardness ΔH The surface layer has a difference ΔH between the maximum and minimum ultra-microhardness values ​​measured at 50 arbitrary points using the ultra-microhardness test specified in JIS Z2255 (2003), which is between 0 and 15. A difference ΔH of less than or equal to the above upper limit indicates that organopolysiloxane (T-type) and dimethylorganopolysiloxane (D-type) are dispersed in the surface layer, and unevenness between the two is suppressed. Therefore, by having a difference ΔH of less than or equal to the above upper limit, the surface layer is made more flexible while ensuring release properties from the toner. As a result, sufficient pressure is applied to the luminous toner particles from the fixing member, the luminous pigment is oriented along the planar direction of the recording medium, and the luminosity of the image is enhanced. From the viewpoint of further enhancing the luminosity of the image, it is preferable that the difference ΔH of the surface layer be between 0 and 5.

[0052] From the viewpoint of controlling the difference ΔH between the maximum and minimum values ​​of ultrafine hardness to the above range, it is preferable to use compounds of organopolysiloxane (T-type) and dimethylorganopolysiloxane (D-type) that are in solution state at room temperature (i.e., 25°C). Furthermore, it is preferable to use a combination of highly compatible materials for organopolysiloxane (T-type) and dimethylorganopolysiloxane (D-type) so that they disperse well when kneaded.

[0053] • Average value of ratio B / A × 100(%) Preferably, the surface layer has an average value of 45% or less for the ratio B / A × 100 (%) of the indentation amount B when the load is released to the indentation amount A when the load is applied, as specified in the ultra-microhardness test of JIS Z2255 (2003). An average value of B / A × 100 (%) within the above range means that the hysteresis loss in the surface layer is small. Furthermore, if the average value of the surface layer's ratio B / A × 100 (%) is below the above upper limit, images with high brilliance can be stably obtained when continuously forming images with brilliance.

[0054] The brilliance of an image when using brilliant toner particles can be enhanced by orienting the brilliant pigment along the planar direction of the recording medium, as well as by increasing the smoothness of the image surface to suppress light scattering. The smoothness of the image surface is affected by the smoothness of the surface of the fixing member that comes into direct contact with the toner image during fixing. However, when using brilliant toner particles containing flattened brilliant pigment, the brilliant pigment that is exposed from the binder resin constituting the toner particles and protrudes from the surface of the toner particles may come into contact with the surface of the fixing member during fixing, causing scratches on the fixing member. As a result, the smoothness of the surface of the fixing member decreases, and the smoothness of the surface of the formed image also decreases, making it difficult to stably obtain a brilliant image.

[0055] In contrast, when the average value of the surface layer ratio B / A × 100 (%) falls within the above range, the hysteresis loss in the surface layer is reduced. Therefore, even if the glossy pigment exposed from the surface of the toner particles comes into contact with the surface layer of the fixing member, the surface layer is less likely to be damaged. As a result, when continuously forming glossy images, images with high glossiness can be stably obtained.

[0056] The average value of the surface layer ratio B / A × 100 (%) is more preferably 40% or less, from the viewpoint of stably obtaining images with high brilliance. Furthermore, while there is no particular lower limit to the average value of the surface layer ratio B / A × 100 (%), it is preferably, for example, 30% or less.

[0057] From the viewpoint of controlling the average value of the surface layer ratio B / A × 100 (%) to the above range, it is preferable to use compounds of organopolysiloxane (T-type) and dimethylorganopolysiloxane (D-type) that are in solution state at room temperature (i.e., 25°C). Furthermore, it is preferable to use a combination of highly compatible materials for organopolysiloxane (T-type) and dimethylorganopolysiloxane (D-type) so that they disperse well when kneaded.

[0058] • Tensile elongation The surface layer preferably has a tensile elongation of 100 or more, and more preferably 150 or more. While there is no particular upper limit to the tensile elongation of the surface layer, it is preferably, for example, 350 or less. By having the lower limit of the tensile elongation within the above range, the surface layer maintains strength while increasing flexibility, allowing sufficient pressure to be applied from the fixing member to the glossy toner particles, thereby enhancing the glossiness of the image.

[0059] The method for measuring the tensile elongation of the surface layer is as follows: Using a tensile testing machine (MODEL-1605N, manufactured by Aiko Engineering Co., Ltd.), a piece of 80 mm x 5 mm is cut out so that the circumferential direction of the surface layer is the longer side. The test is then conducted with a test piece length of 40 mm between the chuck fixtures at a tensile speed of 20 mm / min, and the tensile elongation is calculated.

[0060] To control the tensile elongation within the above range, it is preferable that the surface layer contains a dispersion of organopolysiloxane (T-type) and dimethylorganopolysiloxane (D-type), with unevenness between the two suppressed. Therefore, it is preferable to use compounds of both organopolysiloxane (T-type) and dimethylorganopolysiloxane (D-type) that are in solution at room temperature (i.e., 25°C). Furthermore, it is preferable to use a combination of highly compatible materials for organopolysiloxane (T-type) and dimethylorganopolysiloxane (D-type) so that they disperse well when kneaded.

[0061] • Surface roughness of the surface layer The surface roughness Ra of the outer surface of the surface layer, that is, the surface in contact with the toner image, is preferably 1 μm or less, and more preferably 0.5 μm or less. A surface roughness Ra within this range enhances the smoothness of the formed image surface and further improves the image's luster. The lower limit of the surface roughness Ra is not particularly limited and may be 0 μm.

[0062] The surface roughness Ra is determined as follows: A sample is cut from the surface layer (or a fixing member having a surface layer). The Ra is measured on the sample using a stylus-type surface roughness measuring instrument (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.

[0063] • Film thickness of the surface layer The average thickness of the surface layer is preferably 30 μm or less, and more preferably 15 μm or more and 25 μm or less, from the viewpoint of heat transfer to the toner.

[0064] • Method for forming a surface layer As a method for forming the surface layer, for example, a specific composition is first prepared by mixing liquid organopolysiloxane (Type T) and liquid dimethylorganopolysiloxane (Type D). The obtained specific composition is then coated by immersing a cylindrical mold on which the base material of the fixing member is installed, and curing, thereby forming a surface layer on the base material.

[0065] (Base material and elastic layer) The fixing member has at least a surface layer and may further have a base material. Furthermore, the surface layer may have an elastic layer between the base material and the surface layer.

[0066] The fixing member according to this embodiment will be described below with reference to Figure 1. Figure 1 is a schematic cross-sectional view showing an example of a fixing member according to this embodiment. The fixing member 110 shown in Figure 1 comprises a base layer 110A, an elastic layer 110B provided on the base layer 110A, and a surface layer 110C provided on the elastic layer 110B.

[0067] The layer configuration of the fixing member 110 according to this embodiment is not limited to the layer configuration shown in Figure 1, and it may not have an elastic layer 110B, nor may it have a base layer 110A. The layer configuration of the fixing member 110 according to this embodiment may be a layer configuration in which a metal layer and its protective layer are interposed between the base layer 110A and the elastic layer 110B, a layer configuration in which an adhesive layer is interposed between the base layer 110A and the elastic layer 110B, a layer configuration in which an adhesive layer is interposed between the elastic layer 110B and the surface layer 110C, or a layer configuration that combines these layer configurations.

[0068] The components of the fixing member according to this embodiment will be described in detail below. Reference numerals will be omitted in the description.

[0069] ·Base material layer Examples of the base layer include a resin layer containing a resin such as polyimide. The resin may also contain additives such as fillers.

[0070] Examples of polyimides include imidized polyamic acid (a precursor of polyimide), which is a polymer of tetracarboxylic dianhydride and a diamine compound. Specifically, examples of polyimides include resins obtained by polymerizing equimolar amounts of tetracarboxylic dianhydride and a diamine compound in a solvent to obtain a solution of polyamic acid, and then imidizing that polyamic acid.

[0071] Examples of tetracarboxylic dianhydrides include both aromatic and aliphatic compounds, but from the viewpoint of heat resistance, aromatic compounds are preferred.

[0072] Examples of aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenylsulfone tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3',4,4'-biphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3',4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furan tetracarboxylic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride, 4,4 Examples include '-bis(3,4-dicarboxyphenoxy)diphenylsulfone dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, 3,3',4,4'-perfluoroisopropylidene diphthalic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, 2,3,3',4'-biphenyltetracarboxylic acid dianhydride, bis(phthalic acid)phenylphosphine oxide dianhydride, p-phenylene-bis(triphenylphthalic acid) dianhydride, m-phenylene-bis(triphenylphthalic acid) dianhydride, bis(triphenylphthalic acid)-4,4'-diphenyl ether dianhydride, and bis(triphenylphthalic acid)-4,4'-diphenylmethane dianhydride.

[0073] Examples of aliphatic tetracarboxylic dianhydrides include butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 3,5,6-tricarboxynorbonane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofurantetracarboxylic dianhydride, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid dianhydride, and bicyclo[2,2,2]-octo-7-e Examples include aliphatic or alicyclic tetracarboxylic dianhydrides such as n-2,3,5,6-tetracarboxylic dianhydrides; and aliphatic tetracarboxylic dianhydrides having aromatic rings such as 1,3,3a,4,5,9b-hexahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-5-methyl-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione, and 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione.

[0074] Among these, aromatic tetracarboxylic dianhydrides are particularly well-suited as tetracarboxylic dianhydrides. Specifically, for example, pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-biphenylether tetracarboxylic dianhydride, and 3,3',4,4'-benzophenone tetracarboxylic dianhydride are well-suited. Furthermore, pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, and 3,3',4,4'-benzophenone tetracarboxylic dianhydride are particularly well-suited, especially 3,3',4,4'-bi Phenylate tetracarboxylic dianhydride is a good choice.

[0075] Furthermore, tetracarboxylic dianhydrides may be used individually or in combination of two or more types. Furthermore, when using two or more tetracarboxylic dianhydrides in combination, aromatic tetracarboxylic dianhydrides or aliphatic tetracarboxylic dianhydrides may be used individually, or aromatic tetracarboxylic dianhydrides and aliphatic tetracarboxylic dianhydrides may be used in combination.

[0076] On the other hand, diamine compounds are diamine compounds that have two amino groups in their molecular structure. Diamine compounds can be either aromatic or aliphatic compounds, but aromatic compounds are preferred.

[0077] Examples of diamine compounds include p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 1,5-diaminonaphthalene, 3,3-dimethyl-4,4'-diaminobiphenyl, 5-amino-1-(4'-aminophenyl)-1,3,3-trimethylindan, and 6-amino-1-(4'-aminophenyl)-1,3 ,3-trimethylindan, 4,4'-diaminobenzanilide, 3,5-diamino-3'-trifluoromethylbenzanilide, 3,5-diamino-4'-trifluoromethylbenzanilide, 3,4'-diaminodiphenyl ether, 2,7-diaminofluorene, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-methylene-bis(2-chloroaniline), 2,2',5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diamino-5,5'-dimethyl Toxybiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)-biphenyl, 1,3'-bis(4-aminophenoxy)benzene, 9,9-bis(4-aminophenyl)fluorene Aromatic diamines such as 4,4'-(p-phenyleneisopropylidene)bisaniline, 4,4'-(m-phenyleneisopropylidene)bisaniline, 2,2'-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]hexafluoropropane, and 4,4'-bis[4-(4-amino-2-trifluoromethyl)phenoxy]-octafluorobiphenyl; aromatic diamines such as diaminotetraphenylthiophene having two amino groups bonded to an aromatic ring and heteroatoms other than the nitrogen atom of the amino groups;1,1-Metaxylylenediamine, 1,3-Propanediamine, Tetramethylenediamine, Pentamethylenediamine, Octamethylenediamine, Nonameethylenediamine, 4,4-Diaminoheptamethylenediamine, 1,4-Diaminocyclohexane, Isophoronediamine, Tetrahydrodicyclopentadienylenediamine, Hexahydro-4,7-Methanoindanidinemethylenediamine, Tricyclo[6,2,1,0; 2.7 Examples include aliphatic diamines such as ]-undecylendimethyldiamine and 4,4'-methylenebis(cyclohexylamine), as well as alicyclic diamines.

[0078] Among these, aromatic diamine compounds are particularly good as diamine compounds. Specifically, for example, p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, and 4,4'-diaminodiphenyl sulfone are good, with 4,4'-diaminodiphenyl ether and p-phenylenediamine being particularly good.

[0079] Furthermore, the diamine compounds may be used individually or in combination of two or more. Furthermore, when using two or more diamine compounds in combination, aromatic diamine compounds or aliphatic diamine compounds may be used individually, or aromatic diamine compounds and aliphatic diamine compounds may be used in combination.

[0080] Among these, from the viewpoint of heat resistance, aromatic polyimides (specifically, imidides of polyamic acids (precursors of polyimides), which are polymers of aromatic tetracarboxylic dianhydrides and aromatic diamine compounds) are preferred as polyimides. Furthermore, it is more preferable that the aromatic polyimide is a polyimide having a structural unit represented by the following general formula (PI1).

[0081] [ka]

[0082] In the general formula (PI1), RP1 represents a phenyl group or a biphenyl group, and RP2 represents a divalent aromatic group. Examples of divalent aromatic groups represented by RP2 include phenylene groups, naphthyl groups, biphenyl groups, and diphenyl ether groups. From the viewpoint of bending durability, phenylene groups and biphenyl groups are preferred as divalent aromatic groups.

[0083] The number-average molecular weight of polyimide is preferably 5,000 to 100,000, more preferably 7,000 to 50,000, and even more preferably 10,000 to 30,000.

[0084] The number-average molecular weight of polyimide is measured by gel permeation chromatography (GPC) under the following measurement conditions. • Column: Tosoh TSKgelα-M (7.8mm ID x 30cm) • Eluent: DMF (dimethylformamide) / 30 mM iBr / 60 mM phosphoric acid ·Flow rate: 0.6mL / min ·Injection volume: 60μL • Detector: RI (Differential Refractive Index Detector)

[0085] Examples of fillers include carbon materials such as acetylene black, graphite, graphitized carbon black, and ungraphitized carbon black; and metal nitrides such as aluminum nitride, silicon nitride, boron nitride, cerium oxide, and magnesium carbonate.

[0086] The substrate layer may further contain other additives besides the polyimide and filler mentioned above. Examples of other additives include softeners (paraffin-based, etc.), processing aids (stearic acid, etc.), antioxidants (amine-based, etc.), and vulcanizing agents (sulfur, metal oxides, peroxides, etc.).

[0087] The thickness of the substrate layer is preferably 30 μm to 200 μm, and particularly preferably 50 μm to 150 μm, from the viewpoint of thermal conductivity and mechanical strength.

[0088] The base layer is obtained by preparing a coating solution for forming the base layer containing polyimide (which may also contain additives such as fillers), applying the coating solution for forming the base layer onto a cylindrical mold, and drying it.

[0089] • Elastic layer The elastic layer contains an elastic material. In addition to the elastic material, the elastic layer may also contain well-known additives.

[0090] Examples of elastic materials include fluororesins, silicone resins, silicone rubber, fluororubber, and fluorosilicone rubber. Among these, silicone rubber and fluororubber are preferred as elastic materials from the viewpoint of heat resistance, thermal conductivity, and insulation, with silicone rubber being more preferred.

[0091] Examples of silicone rubber include RTV silicone rubber, HTV silicone rubber, and liquid silicone rubber. Specifically, examples include polydimethyl silicone rubber (MQ), methyl vinyl silicone rubber (VMQ), methylphenyl silicone rubber (PMQ), and fluorosilicone rubber (FVMQ).

[0092] As for the silicone rubber, those with an addition reaction type as the crosslinking mechanism are preferred. Furthermore, various types of functional groups are known for silicone rubber, and dimethyl silicone rubber having methyl groups, methylphenyl silicone rubber having methyl and phenyl groups, and vinyl silicone rubber having vinyl groups (vinyl group-containing silicone rubber) are preferred. Furthermore, as the silicone rubber, vinyl silicone rubber having vinyl groups is more preferred, and silicone rubber having an organopolysiloxane structure having vinyl groups and a hydrogen organopolysiloxane structure having hydrogen atoms (SiH) bonded to silicon atoms is even more preferred.

[0093] Examples of fluororubbers include vinylidene fluoride rubber, tetrafluoroethylene / propylene rubber, tetrafluoroethylene / perfluoromethyl vinyl ether rubber, phosphophazene rubber, and fluoropolyether.

[0094] The elastic material preferably has silicone rubber as its main component (i.e., contains 50% or more by mass of silicone rubber relative to the total mass of the elastic material). The silicone rubber content is more preferably 90% by mass or more, even more preferably 99% by mass or more, and may be 100% by mass, based on the total mass of the elastic material used in the elastic layer (1).

[0095] Possible additives in the elastic layer include fillers, softeners (paraffin-based, etc.), processing aids (stearic acid, etc.), antioxidants (amine-based, etc.), and vulcanizing agents (sulfur, metal oxides, peroxides, etc.). It may contain additives such as the following.

[0096] The elastic layer can be formed by applying known methods, such as a coating method. When using silicone rubber as the elastic material for the elastic layer, for example, first, a coating solution for forming the elastic layer is prepared, which contains liquid silicone rubber that hardens into silicone rubber upon heating. Next, the coating solution for forming the elastic layer is applied to the substrate layer to form a coating film, and the coating film is vulcanized as needed to form an elastic layer on the substrate layer. In the vulcanization of the coating film, for example, the vulcanization temperature is 150°C to 250°C, and the vulcanization time is 30 minutes to 120 minutes.

[0097] • Film thickness of the elastic layer The average thickness of the elastic layer is preferably 300 μm or more, and more preferably 400 μm to 500 μm, from the viewpoint of applying sufficient pressure from the fixing member to the glossy toner particles and enhancing the glossiness of the image.

[0098] [Developer] The electrostatic image developer contains toner, and the toner contains toner particles. The toner particles contain a metallic pigment with an average equivalent circular diameter of 5 μm or more and 15 μm or less, the average value of the ratio b / a of the major axis diameter a to the minor axis diameter b in the cross-section of the toner particles is 0.5 or more and 0.8 or less, and the average value of the area of ​​the metallic pigment in the projected image of the toner particles when viewed from the thickness direction is 0.5 or more and 0.7 or less.

[0099] • Mean value of ratio b / a The glossy toner particles have an average ratio b / a of the major axis diameter a to the minor axis diameter b in their cross-section that is between 0.5 and 0.8. Preferably, the average ratio b / a is between 0.55 and 0.75, and more preferably between 0.6 and 0.7. If the average ratio b / a is less than 0.5, the coating of metal pigments by the binder resin may decrease. On the other hand, if the average ratio b / a exceeds 0.8, the brilliance of the fixed image may decrease.

[0100] In this embodiment, the method for measuring the major axis diameter a and minor axis diameter b in the cross-section of toner particles is as follows: Toner particles are placed on a smooth surface and dispersed evenly by vibration. For 1000 toner particles, the maximum thickness is measured using a color laser microscope "VK-9700" (manufactured by Keyence Corporation) at 1000x magnification, and the major axis diameter a is measured as the equivalent diameter of a circle on the surface viewed from above. The arithmetic mean of these values ​​is then calculated.

[0101] • Pigment area ratio In glossy toner particles, the average value of the area of ​​the metallic pigment in the projected image of the toner particle when viewed from the thickness direction is also referred to as the "pigment area ratio" in this specification. Glossy toner particles have a pigment area ratio of 0.5 to 0.7. The pigment area ratio is preferably 0.53 to 0.67, and more preferably 0.57 to 0.63. If the pigment area ratio is less than 0.5, the glossiness of the fixed image may decrease. If the pigment area ratio exceeds 0.7, the coating of the metallic pigment by the binder resin may decrease.

[0102] In this embodiment, the method for measuring the pigment area ratio is as follows. The arithmetic mean of the pigment area ratios for 1000 toner particles obtained as described below is taken as the pigment area ratio in this embodiment. The toner particles are dispersed in water using a surfactant. For 1000 toner particles, the light transmission image obtained using an optical microscope "LABOPHOT2" (manufactured by Nikon Corporation) is image-analyzed to determine the total area A of the toner and the area B of the luminous pigment portion inside the toner, and B / A is calculated.

[0103] ·Ratio (X / Y) For electrostatic image developing toners containing luminous toner particles, it is desirable that when a solid image is formed, the ratio (X / Y) of the reflectance X at a receiving angle of +30° to the reflectance Y at a receiving angle of -30°, measured when the image is irradiated with incident light at an incident angle of -45° using a variable-angle photometer, is between 2 and 100.

[0104] A ratio (X / Y) of 2 or greater indicates that there is more reflection of incident light on the opposite side of the incident light (the positive side of the angle) than on the side of the incident light (the negative side of the angle), meaning that diffuse reflection of the incident light is suppressed. When diffuse reflection occurs, where the incident light is reflected in various directions, the reflected light appears dull when viewed visually. Therefore, if the ratio (X / Y) is less than 2, the reflected light may not appear glossy and may have poor luster. On the other hand, if the ratio (X / Y) exceeds 100, the field of view in which reflected light can be seen becomes too narrow, and because the specular reflection component is large, it may appear dark depending on the viewing angle.

[0105] Furthermore, the above ratio (X / Y) is more preferably between 50 and 100, even more preferably between 60 and 90, and particularly preferably between 70 and 80.

[0106] -Measurement of the ratio (X / Y) using a variable-angle photometer- First, let's explain the angle of incidence and the angle of reception. In this embodiment, when measuring with a variable-angle photometer, the angle of incidence is set to -45°. This is because it provides high measurement sensitivity for images with a wide range of gloss levels. Furthermore, the light-receiving angles will be set to -30° and +30°. This is because these angles provide the highest measurement sensitivity for evaluating images with and without luminosity.

[0107] Next, we will explain how to measure the ratio (X / Y). In this embodiment, when measuring the ratio (X / Y), a "solid image" is first formed by the following method. The developer to be used as the sample is filled into the developer unit of a DocuCentre-III C7600 manufactured by Fujifilm Business Innovation Co., Ltd., and the image is placed on recording paper (OK Topcoat+ paper, manufactured by Oji Paper Co., Ltd.) at a fixing temperature of 190°C and a fixing pressure of 4.0 kg / cm². 2 The toner load is 4.5g / m². 2 This forms a solid image. Note that the term "solid image" refers to an image with 100% print coverage. For the image portion of the formed solid image, a GC5000L spectroscopic colorimeter manufactured by Nippon Denshoku Industries Co., Ltd. was used as a variable-angle photometer. Incident light at an incident angle of -45° was applied to the solid image, and the reflectance X at a reception angle of +30° and the reflectance Y at a reception angle of -30° were measured. Reflectances X and Y were measured at 20nm intervals for light with wavelengths ranging from 400nm to 700nm, and the average reflectance at each wavelength was used. From these measurement results, the ratio (X / Y) was calculated.

[0108] <Toner Configuration> The luminous toner particles should preferably meet the following requirements (1) or (2) from the viewpoint of satisfying the aforementioned ratio (X / Y). (1) The average equivalent diameter D of the luminous toner particles is longer than the average maximum thickness C. (2) When the cross-section of the luminous toner particles in the thickness direction is observed, the number of metal pigments in which the angle between the long axis direction of the toner in the cross-section and the long axis direction of the metal pigment is in the range of -30° to +30° is 60% or more of all metal pigments observed. The average maximum toner thickness C corresponds to the arithmetic mean of the minor axis diameter b in the cross-section of the toner particles. The average equivalent circular diameter D of the toner corresponds to the arithmetic mean of the major axis diameter a in the cross-section of the toner particles.

[0109] Here, Figure 2 shows a schematic cross-sectional view of luminous toner particles that satisfy the requirements of (1) to (2) above. Note that the schematic view shown in Figure 2 is a cross-sectional view of the luminous toner particles in the thickness direction. The luminous toner particles 23 shown in Figure 2 are flattened toners with an equivalent circular diameter longer than their thickness L, and contain flaky metal pigments 24.

[0110] As shown in Figure 2, consider the case where the glossy toner particles 23 are flattened, with an equivalent diameter longer than the thickness L. In this case, during the development and transfer processes of image formation, when the toner moves to the image holder, intermediate transfer medium, recording medium, etc., it tends to move in a way that cancels out the charge of the toner as much as possible. Therefore, it is thought that the glossy toner particles are arranged to maximize the surface area of ​​adhesion. That is, on the recording medium to which the toner is finally transferred, it is thought that the flattened glossy toner particles are arranged so that their flat side faces the surface of the recording medium. Furthermore, during the fixing process of image formation, it is thought that the pressure during fixing causes the flattened glossy toner particles to be arranged so that their flat side faces the surface of the recording medium. Therefore, among the flake-shaped metal pigments contained in these lustrous toner particles, the metal pigments that satisfy the requirement shown in (2) above, "the angle between the long axis direction of the cross-section of the lustrous toner particle and the long axis direction of the metal pigment is in the range of -30° to +30°", are thought to be arranged so that the side with the largest area faces the surface of the recording medium. When light is irradiated onto the image thus formed, the proportion of metal pigments that are diffusely reflected from the incident light is suppressed, so the aforementioned range of ratio (X / Y) is achieved. Furthermore, when the proportion of metal pigments that are diffusely reflected from the incident light is suppressed, the reflected light intensity changes greatly depending on the viewing angle, so a more ideal luster can be obtained.

[0111] Next, the components constituting the toner used in this embodiment will be described. The toner used in this embodiment comprises toner particles and, if necessary, an external additive. The toner particles used are bright toner particles that meet the aforementioned requirements. The toner particles are composed of, for example, a specific metal pigment, a binder resin, a release agent, and other additives. The binder resin includes, for example, crystalline resins and amorphous resins.

[0112] -Metallic pigments- The metallic pigment used in the lustrous toner particles of this embodiment is a metallic pigment with an average equivalent circle diameter of 5 μm to 15 μm. If the average equivalent circle diameter of the metallic pigment is outside the range of 5 μm to 15 μm, the luster of the image may decrease. The average equivalent diameter of the metal pigment is preferably 7 μm to 13 μm, and more preferably 9 μm to 11 μm.

[0113] The following are examples of metal pigment components used in this embodiment. For example, metal powders such as aluminum, brass, bronze, nickel, stainless steel, and zinc; coated flake-like inorganic crystalline substrates such as mica coated with titanium oxide or yellow iron oxide, barium sulfate, layered silicates, and layered aluminum silicates; single-crystal plate-like titanium oxide; basic carbonates; bismuth oxychloride; and metal-deposited flake-like glass powder. Any pigment containing metal and having lustrous properties is not particularly limited. In this embodiment, "lustrous property" refers to the metallic luster-like shine that the image formed by the toner of this embodiment has when viewed.

[0114] In this embodiment, the average equivalent circle diameter of the metal pigment refers to the value measured as follows. Metallic pigments are placed on a smooth surface and dispersed evenly by vibration. For 1000 metallic pigments, the equivalent circular diameter D of the surface of the metallic pigment viewed from above is measured by magnifying it 1000 times using a color laser microscope "VK-9700" (manufactured by Keyence Corporation), and the arithmetic mean of these measurements is calculated. The method for extracting metallic pigments from toner is not particularly limited. For example, metallic pigments can be extracted from toner using the following method. The toner is dispersed in an organic solvent such as toluene to dissolve the binder resin, then insoluble components are separated using filter paper, and the metallic pigment is extracted by drying.

[0115] In the toner of this embodiment, the content of the metal pigment is preferably 1 to 70 parts by mass per 100 parts by mass of the binder resin described later. More preferably, it is 5 to 50 parts by mass.

[0116] -Binding resin- The toner particles of this embodiment may contain a binder resin. Preferably, the binder resin contains both a crystalline resin and an amorphous resin. In this embodiment, the proportion of crystalline resin in the binder resin is preferably 3% by mass or more and 30% by mass or less. More preferably 5% by mass or more and 25% by mass or less, and even more preferably 10% by mass or more and 20% by mass or less. If the proportion of crystalline resin in the binder resin is 3% by mass or more, the abrasion resistance of the toner image is improved. If the proportion of crystalline resin in the binder resin is 30% by mass or less, the increase in diffuse reflection of the image caused by the presence of crystalline resin is suppressed.

[0117] Examples of binder resins include vinyl resins consisting of monomers such as styrenes (e.g., styrene, parachlorostyrene, α-methylstyrene, etc.), (meth)acrylic acid esters (e.g., methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, etc.), ethylenically unsaturated nitriles (e.g., acrylonitrile, methacrylonitrile, etc.), vinyl ethers (e.g., vinyl methyl ether, vinyl isobutyl ether, etc.), vinyl ketones (vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone, etc.), and olefins (e.g., ethylene, propylene, butadiene, etc.), or copolymers of two or more of these monomers. Examples of binder resins include non-vinyl resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, and modified rosin; mixtures of these with the aforementioned vinyl resins; and graft polymers obtained by polymerizing vinyl monomers in the presence of these.

[0118] Polyester resin is preferred as the binder resin. Examples of polyester resins include known amorphous polyester resins. In addition to amorphous polyester resins, crystalline polyester resins may also be used in combination.

[0119] Furthermore, the "crystalline nature" of a resin refers to the presence of a clear endothermic peak rather than a stepwise change in endothermic quantity in differential scanning calorimetry (DSC). Specifically, it means that the full width at half maximum of the endothermic peak measured at a heating rate of 10°C / min is within 10°C. On the other hand, "amorphous" resins refer to those with a full width at half maximum exceeding 10°C, exhibiting a stepwise change in endothermic capacity, or lacking a clear endothermic peak.

[0120] Amorphous polyester resin Examples of amorphous polyester resins include condensation polymers of polycarboxylic acids and polyhydric alcohols. The amorphous polyester resin may be a commercially available product or a synthesized one.

[0121] Examples of polycarboxylic acids include aliphatic dicarboxylic acids (e.g., oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, alkenylsuccinic acid, adipic acid, sebacic acid, etc.), alicyclic dicarboxylic acids (e.g., cyclohexanedicarboxylic acid, etc.), aromatic dicarboxylic acids (e.g., terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, etc.), their anhydrides, or their lower alkyl esters (e.g., with 1 to 5 carbon atoms). Among these, aromatic dicarboxylic acids are preferred as polycarboxylic acids. Polycarboxylic acids may be used in combination with dicarboxylic acids, or with trivalent or higher carboxylic acids that have a cross-linked or branched structure. Examples of trivalent or higher carboxylic acids include trimellitic acid, pyromellitic acid, their anhydrides, or their lower alkyl esters (e.g., having 1 to 5 carbon atoms). Polycarboxylic acids may be used individually or in combination of two or more.

[0122] Examples of polyhydric alcohols include aliphatic diols (e.g., ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, etc.), alicyclic diols (e.g., cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, etc.), and aromatic diols (e.g., ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, etc.). Among these, aromatic diols and alicyclic diols are preferred as polyhydric alcohols, and aromatic diols are more preferred. As for the polyhydric alcohol, a trihydric or higher polyhydric alcohol with a cross-linked or branched structure may be used in combination with the diol. Examples of trihydric or higher polyhydric alcohols include glycerin, trimethylolpropane, and pentaerythritol. Polyhydric alcohols may be used individually or in combination of two or more types.

[0123] The glass transition temperature (Tg) of amorphous polyester resin is preferably 50°C to 80°C, and more preferably 50°C to 65°C. The glass transition temperature is determined from the DSC curve obtained by differential scanning calorimetry (DSC), and more specifically, it is determined by the "extracorporeal glass transition onset temperature" described in the method for determining the glass transition temperature in JIS K-7121-1987 "Method for Measuring the Transition Temperature of Plastics".

[0124] The weight-average molecular weight (Mw) of the amorphous polyester resin is preferably 5,000 to 1,000,000, and more preferably 7,000 to 500,000. The number-average molecular weight (Mn) of the amorphous polyester resin is preferably between 2,000 and 100,000. The molecular weight distribution (Mw / Mn) of the amorphous polyester resin is preferably 1.5 to 100, and more preferably 2 to 60. The weight-average molecular weight and number-average molecular weight are measured by gel permeation chromatography (GPC). GPC molecular weight measurement is performed using a Tosoh GPC-HLC-8120GPC analyzer, a Tosoh TSKgel SuperHM-M (15cm) column, and tetrahydrofuran (THF) solvent. The weight-average molecular weight and number-average molecular weight are calculated from these measurement results using a molecular weight calibration curve prepared with monodisperse polystyrene standard samples.

[0125] Amorphous polyester resins can be obtained by well-known manufacturing methods. Specifically, for example, they can be obtained by a method in which the polymerization temperature is set to 180°C or higher and 230°C or lower, and the reaction system is subjected to reduced pressure as needed, while removing water and alcohol generated during condensation. If the monomers of the raw materials do not dissolve or become miscible at the reaction temperature, a high-boiling point solvent may be added as a solubilizer to dissolve them. In this case, the polycondensation reaction should be carried out while distilling off the solubilizer. If there are monomers with poor miscibility in the copolymerization reaction, it is advisable to condense the poorly miscible monomers with the acid or alcohol to be polycondensed with them beforehand, and then polycondense them together with the main component.

[0126] • Crystalline polyester resin Crystalline polyester resins include, for example, polycondensates of polycarboxylic acids and polyhydric alcohols. Commercially available crystalline polyester resins may be used, or synthesized resins may be used. Here, in order to easily form a crystalline structure, polycondensates using polymerizable monomers having linear aliphatic structures are preferred over polymerizable monomers having aromatic structures.

[0127] Examples of polycarboxylic acids include aliphatic dicarboxylic acids (e.g., oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, etc.), aromatic dicarboxylic acids (e.g., phthalic acid, isophthalic acid, terephthalic acid, dibasic acids such as naphthalene-2,6-dicarboxylic acid, etc.), their anhydrides, or their lower alkyl esters (e.g., having 1 to 5 carbon atoms). Polycarboxylic acids may be used in combination with dicarboxylic acids, or with trivalent or higher carboxylic acids that have a crosslinked or branched structure. Examples of trivalent carboxylic acids include aromatic carboxylic acids (e.g., 1,2,3-benzenetricarboxylic acid, 1,2,4-benzenetricarboxylic acid, 1,2,4-naphthalentricarboxylic acid, etc.), their anhydrides, or their lower alkyl esters (e.g., having 1 to 5 carbon atoms). In addition to these dicarboxylic acids, polycarboxylic acids with sulfonic acid groups and dicarboxylic acids with ethylenic double bonds may also be used in combination. Polycarboxylic acids may be used individually or in combination of two or more.

[0128] Examples of polyhydric alcohols include aliphatic diols (for example, linear aliphatic diols in which the main chain has 2 to 20 carbon atoms). Examples of aliphatic diols include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, and 1,20-icosanediol. Among these, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferred as aliphatic diols. Polyhydric alcohols may be used in combination with diols, including trihydric or higher alcohols that have a cross-linked or branched structure. Examples of trihydric or higher alcohols include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol. Polyhydric alcohols may be used individually or in combination of two or more types.

[0129] Here, the polyhydric alcohol is preferably composed of 80 mol% or more of aliphatic diols, and more preferably 90 mol% or more.

[0130] The melting temperature of the crystalline polyester resin is preferably 50°C to 100°C, more preferably 55°C to 90°C, and even more preferably 60°C to 85°C. The melting temperature is determined from the DSC curve obtained by differential scanning calorimetry (DSC) using the "melting peak temperature" described in JIS K7121-1987 "Method for determining the transition temperature of plastics".

[0131] The weight-average molecular weight (Mw) of the crystalline polyester resin is preferably between 6,000 and 35,000.

[0132] Crystalline polyester resins can be obtained, for example, by well-known manufacturing methods, similar to amorphous polyesters.

[0133] The binder resin content is preferably 40% to 95% by mass, more preferably 50% to 90% by mass, and even more preferably 60% to 90% by mass, relative to the total toner particles.

[0134] -Release agent- Examples of release agents include hydrocarbon waxes; natural waxes such as carnauba wax, rice wax, and candelilla wax; synthetic or mineral / petroleum-based waxes such as montan wax; and ester waxes such as fatty acid esters and montanic acid esters. However, the release agents are not limited to these.

[0135] The melting temperature of the release agent is preferably 50°C to 110°C, and more preferably 60°C to 100°C. The melting temperature is determined from the DSC curve obtained by differential scanning calorimetry (DSC) using the "melting peak temperature" described in JIS K-7121-1987 "Method for determining the transition temperature of plastics".

[0136] The release agent content is preferably 1% to 20% by mass, and more preferably 4% to 15% by mass, relative to the total toner particles.

[0137] -Other additives- Other additives include well-known additives such as magnetic materials, charge control agents, and inorganic powders. These additives are included in the toner particles as internal additives.

[0138] -Characteristics of luminous toner particles, etc.- The bright toner particles may be single-layer toner particles, or they may be toner particles with a so-called core-shell structure, consisting of a core (core particle) and a coating layer (shell layer) that covers the core. Here, the core-shell structure of the toner particles preferably comprises, for example, a core portion composed of a binder resin, a metal pigment (colorant), and other additives such as a mold release agent as needed, and a coating layer composed of a binder resin.

[0139] The volume-average particle size (D50v) of the luminous toner particles is preferably 5 μm or more and 30 μm or less.

[0140] The average particle size and particle size distribution indices of the toner particles are measured using a Coulter Multisizer 4e (manufactured by Beckman Coulter), and the electrolyte is measured using ISOTON-II (manufactured by Beckman Coulter). For measurement, add 0.5 mg to 50 mg of the sample to be measured in 2 ml of a 5% aqueous solution of a surfactant (preferably sodium alkylbenzenesulfonate) as a dispersant. Add this to 100 ml to 150 ml of electrolyte. The electrolyte containing the suspended sample is dispersed in an ultrasonic disperser for 1 minute. The particle size distribution of particles with a diameter of 2 μm to 60 μm is then measured using a Coulter Multisizer 4e with an aperture diameter of 100 μm. The number of particles sampled is 50,000. Based on the measured particle size distribution, a cumulative distribution of volume and number is drawn for each divided particle size range (channel) from the smallest diameter side. The particle size at which the cumulative total reaches 16% is defined as the volume particle size D16v and the number particle size D16p, the particle size at which the cumulative total reaches 50% is defined as the volume average particle size D50v and the cumulative number average particle size D50p, and the particle size at which the cumulative total reaches 84% ​​is defined as the volume particle size D84v and the number particle size D84p. Using these, the volume-average particle size distribution index (GSDv) is (D84v / D16v) 1 / 2 The number-mean granularity distribution index (GSDp) is (D84p / D16p). 1 / 2 It is calculated as follows.

[0141] The shape factor SF1 of the luminous toner particles is preferably 110 to 150, and more preferably 120 to 140.

[0142] The shape factor SF1 can be calculated using the following formula. Formula: SF1=(ML 2 / A) × (π / 4) × 100 In the above formula, ML represents the absolute maximum length of the toner, and A represents the projected area of ​​the toner. Specifically, the shape factor SF1 is quantified primarily by analyzing microscope images or scanning electron microscope (SEM) images using an image analysis device, and is calculated as follows: Optical microscope images of particles scattered on a glass slide surface are captured by a video camera into a Luzex image analysis device, the maximum length and projected area of ​​100 particles are determined, and the average value is calculated using the above formula.

[0143] • Angle between the long axis of the luminous toner particles in the cross-section and the long axis of the metallic pigment. As described in (2) above, when observing the cross-section of the glossy toner particles in the thickness direction, it is desirable that the number of metal pigments in which the angle between the long axis direction of the toner particle in the cross-section and the long axis direction of the metal pigment is in the range of -30° to +30° is in the range of -30° to +30° is 60% or more of all observed metal pigments. Furthermore, it is more desirable that the above number be 70% to 95%, and particularly desirable that it be 80% to 90%. Excellent luster can be achieved when the above percentage is 60% or higher.

[0144] Here, we will explain how to observe the cross-section of toner particles. Toner particles are embedded in a bisphenol A type liquid epoxy resin and a hardener, and then a sample for cutting is prepared. Next, the sample for cutting is cut at -100°C using a cutting machine with a diamond knife (in this embodiment, a LEICA ultramicrotome (manufactured by Hitachi Technologies) is used) to prepare an observation sample. The cross-section of the toner particles in this observation sample is observed at a magnification of approximately 5000x using a transmission electron microscope (TEM). For the 1000 observed toner particles, the number of metal pigments whose angle between the long axis direction of the toner particle cross-section and the long axis direction of the metal pigment is in the range of -30° to +30° is counted using image analysis software, and the proportion is calculated.

[0145] Furthermore, "the long axis direction in the cross-section of the toner particle" refers to the direction perpendicular to the thickness direction for toner particles where the average equivalent circle diameter D is longer than the average maximum thickness C mentioned above, and "the long axis direction of the metallic pigment" refers to the length direction of the metallic pigment.

[0146] (External additive) Examples of external additives include inorganic particles. These inorganic particles include SiO2, TiO2, Al2O3, SrTiO3, CaTiO3, CuO, ZnO, SnO2, CeO2, Fe2O3, MgO, BaO, CaO, K2O, Na2O, ZrO2, CaO·SiO2, and K2O·(TiO2). n Examples include Al2O3·2SiO2, CaCO3, MgCO3, BaSO4, and MgSO4.

[0147] The surface of the inorganic particles used as an external additive should preferably be hydrophobic. Hydrophobic treatment is carried out, for example, by immersing the inorganic particles in a hydrophobic agent. The hydrophobic agent is not particularly limited, but examples include silane-based coupling agents, silicone oil, titanate-based coupling agents, and aluminum-based coupling agents. These may be used individually or in combination of two or more. The amount of hydrophobic treatment agent is typically, for example, 1 to 10 parts by mass per 100 parts by mass of inorganic particles.

[0148] Examples of external additives include resin particles (such as polystyrene, polymethyl methacrylate (PMMA), and melamine resin), and cleaning activators (for example, metal salts of higher fatty acids represented by zinc stearate, and higher alcohols).

[0149] The amount of external additive is preferably 0.01% by mass or more and 10.0% by mass or less relative to the toner particles, and more preferably 0.01% by mass or more and 6.0% by mass or less.

[0150] The toner of this embodiment may also be manufactured by adding an external additive to the toner particles after the toner particles have been produced. The method for producing toner particles is not particularly limited and can be dry methods such as known kneading and grinding methods, or wet methods such as agglomeration, suspension polymerization, or dissolution suspension. The kneading and grinding method involves mixing various materials, including a binder resin, then melt-kneading the materials using a kneader, extruder, etc., coarsely grinding the resulting molten mixture, then grinding it further with a jet mill, etc., and finally obtaining toner particles of the desired particle size using an air classifier. Among these methods, the aggregation and coalescence method is preferable because it allows for easy control of the shape and particle size of toner particles, and offers a wide range of control over the toner particle structure, including the core-shell structure. Furthermore, the aggregation and coalescence method is preferable from the viewpoint that it allows for easy control of the shape and particle size of toner particles and enables the toner resin to be applied to the pigment in a state where unevenness is suppressed. The following describes in detail the method for producing toner particles using the aggregation and coalescence method.

[0151] The agglomeration and coalescence method comprises an emulsification step in which the raw materials constituting toner particles are emulsified to form resin particles (emulsified particles), an agglomeration step in which aggregates the resin particles are formed, and a fusion step in which the aggregates are fused together.

[0152] (emulsification process) In addition to using general polymerization methods such as emulsion polymerization, suspension polymerization, and dispersion polymerization, resin particle dispersions can also be prepared by emulsifying a solution of an aqueous medium and a binder resin by applying shear force with a disperser. In this case, heating may be used to reduce the viscosity of the resin components and form particles. Dispersants may also be used to stabilize the dispersed resin particles. Furthermore, if the resin is oily and soluble in solvents with relatively low solubility in water, the resin can be dissolved in such solvents, dispersed in water with a dispersant and a polymer electrolyte, and then heated or reduced pressure to evaporate the solvent, thereby preparing the resin particle dispersion.

[0153] Examples of aqueous media include water such as distilled water and deionized water; alcohols; however, water is preferable. Furthermore, examples of dispersants used in the emulsification process include water-soluble polymers such as polyvinyl alcohol, methylcellulose, ethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, sodium polyacrylate, and sodium polymethacrylate; anionic surfactants such as sodium dodecylbenzenesulfonate, sodium octadecyl sulfate, sodium oleate, sodium laurylate, and potassium stearate; cationic surfactants such as laurylamine acetate, stearylamine acetate, and lauryltrimethylammonium chloride; amphoteric surfactants such as lauryldimethylamine oxide; and nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, and polyoxyethylene alkylamines; as well as inorganic salts such as tricalcium phosphate, aluminum hydroxide, calcium sulfate, calcium carbonate, and barium carbonate.

[0154] Examples of dispersers used to prepare the emulsified liquid include homogenizers, homomixers, pressurized kneaders, extruders, and media dispersers. The average particle diameter (volume average particle diameter) of the resin particles is preferably 1.0 μm or less, more preferably in the range of 60 nm to 300 nm, and even more preferably in the range of 150 nm to 250 nm. If the particle diameter is 60 nm or greater, the resin particles tend to become unstable in the dispersion, which can easily lead to aggregation of the resin particles. Furthermore, if the particle diameter is 1.0 μm or less, the particle size distribution of the toner may become narrow.

[0155] In preparing the release agent dispersion, the release agent is dispersed in water together with ionic surfactants, polymeric acids, polymeric bases, and other polymeric electrolytes. The dispersion is then heated to a temperature above the melting point of the release agent and dispersed using a homogenizer or pressure-discharge disperser that applies strong shear force. Through this process, a release agent dispersion is obtained. During the dispersion process, inorganic compounds such as polyaluminum chloride may be added to the dispersion. Desirable inorganic compounds include, for example, polyaluminum chloride, aluminum sulfate, highly basic polyaluminum chloride (BAC), polyaluminum hydroxide, and aluminum chloride. Among these, polyaluminum chloride and aluminum sulfate are preferred. The above release agent dispersion is used in the coagulation and coalescence method, but it may also be used when manufacturing toner by suspension polymerization.

[0156] Dispersion treatment yields a release agent dispersion containing release agent particles with a volume-average particle diameter of 1 μm or less. More desirable is a release agent particle with a volume-average particle diameter of 100 nm to 500 nm. When the volume-average particle size is 100 nm or larger, the release agent components are generally more easily incorporated into the toner, although this is also influenced by the properties of the binder resin used. Furthermore, when the particle size is 500 nm or smaller, the dispersion of the release agent in the toner is better.

[0157] The preparation of the colorant (metal pigment) dispersion can be carried out using known dispersion methods, and is not limited in any way; for example, general dispersion methods such as rotary shear homogenizers, ball mills with media, sand mills, dyno mills, and ultimateizers can be employed. The colorant is dispersed in water together with ionic surfactants and polymer electrolytes such as polymer acids and polymer bases. The volume average particle size of the dispersed colorant particles should be 20 μm or less, but a range of 3 μm to 16 μm is desirable as it does not impair aggregation and ensures good dispersion of the colorant in the toner. Alternatively, a dispersion of a lustrous metal pigment coated with a binder resin may be prepared by dispersing and dissolving a lustrous metal pigment and a binder resin in a solvent, mixing them, and then dispersing them in water by phase inversion emulsification or shear emulsification.

[0158] (Agglutination process) In the coagulation process, a mixture of resin particle dispersion, colorant dispersion, and mold release agent dispersion is prepared and heated at a temperature below the glass transition temperature of the resin particles to induce coagulation and form coagulated particles. Coagulated particles are often formed by stirring and adjusting the pH of the mixture to an acidic level. A pH range of 2 to 7 is desirable, and the use of a coagulant is also effective in this process. Furthermore, in the coagulation process, the release agent dispersion may be added and mixed all at once with various dispersions such as the resin particle dispersion, or it may be added in multiple separate steps.

[0159] In the agglomeration process, for example, by using a laminar flow forming agitator with two paddles and stirring at a high speed (for example, 500 rpm to 1500 rpm), the metal pigment aligns in the direction of the long axis within the agglomerated particles, and the agglomerated particles also agglomerate in the direction of the long axis, resulting in a reduced toner thickness (i.e., satisfying requirement (1) above).

[0160] Suitable flocculants include surfactants with opposite polarity to those used in the dispersant, inorganic metal salts, and metal complexes with a valency of 2 or higher. In particular, the use of metal complexes is desirable because it reduces the amount of surfactant used and improves the electrostatic properties.

[0161] As the inorganic metal salt, aluminum salts and their polymers are particularly preferred. To obtain a narrower particle size distribution, inorganic metal salts with a valency of 2 are more suitable than 1, 3 are more suitable than 2, and 4 are more suitable than 3. Furthermore, even with the same valency, inorganic metal salt polymers are more suitable. In this embodiment, it is desirable to use a polymer of a tetravalent inorganic metal salt containing aluminum in order to obtain a narrow particle size distribution.

[0162] Alternatively, a toner can be produced in which the surface of the core aggregated particles is coated with resin by adding a resin particle dispersion (coating step) when the aggregated particles reach a desired particle size. In this case, the release agent and colorant are less likely to be exposed on the toner surface, which is a desirable configuration from the viewpoint of electrostatic properties and developability. When adding the dispersion, a coagulant may be added or the pH adjusted before the dispersion is added.

[0163] (fusion process) In the fusion process, under stirring conditions similar to those in the aggregation process, the pH of the suspension of aggregated particles is raised to a range of 3 to 9 to stop the aggregation process, and the aggregated particles are fused by heating at a temperature above the glass transition temperature of the resin. If the particles are coated with the resin, the resin also fuses and coats the core aggregated particles. The heating time should be sufficient to achieve fusion, and can be approximately 0.5 hours to 10 hours. In the fusion process, fusing the aggregated particles at a lower temperature (for example, 60°C to 80°C) reduces the movement associated with the rearrangement of the material, maintains the orientation of the pigment, and yields toner particles that satisfy the requirements of (2) above.

[0164] After fusion, the mixture is cooled to obtain fused particles. Alternatively, during the cooling process, crystallization may be promoted by slow cooling, where the cooling rate is reduced near the glass transition temperature of the resin (within the range of ±10°C of the glass transition temperature). The fused particles obtained through this process are then subjected to solid-liquid separation processes such as filtration, and, if necessary, washing and drying processes to become toner particles.

[0165] The resulting toner particles are then coated with external additives such as silica, titania, and aluminum oxide for purposes including charge adjustment, fluidity enhancement, and charge exchange. This can be done using, for example, a V-type blender, Henschel mixer, or Redigge mixer, and the additives may be applied in stages. The amount of external additive added is preferably in the range of 0.1 to 5 parts per 100 parts of toner particles, and more preferably in the range of 0.3 to 2 parts. Furthermore, if necessary, coarse toner particles may be removed after external application using ultrasonic screens, vibrating screens, or wind screens.

[0166] In addition to the inorganic oxides mentioned above, other components (particles) such as charge control agents, organic particles, lubricants, and abrasives may also be added as external additives.

[0167] There are no particular restrictions on the charge control agent, but colorless or light-colored ones are preferred. Examples include quaternary ammonium salt compounds, nigrosine compounds, complexes of aluminum, iron, chromium, etc., and triphenylmethane pigments.

[0168] Examples of organic particles include those typically used as external additives for toner surfaces, such as vinyl resins, polyester resins, and silicone resins. These inorganic and organic particles are used as flow enhancers, cleaning aids, and the like. Examples of lubricants include fatty acid amides such as ethylenebis-stearamide and oleamide, and fatty acid metal salts such as zinc stearate and calcium stearate. Examples of abrasives include the aforementioned silica, alumina, and cerium oxide.

[0169] Next, we will explain in detail the method for producing toner particles by the dissolution and suspension method. The dissolution-suspension method involves dissolving or dispersing a material containing a binder resin, a colorant, and other components such as a mold release agent, as needed, in a solvent capable of dissolving the binder resin. Then, the dissolved or dispersed liquid is granulated in an aqueous medium containing an inorganic dispersant, and the solvent is removed to obtain toner particles. Other components used in the dissolution-suspension method include release agents, internal additives, electrostatic control agents, inorganic powders (inorganic particles), organic particles, and various other components.

[0170] In this embodiment, these binder resins, colorants, and other components used as needed are dissolved or dispersed in a solvent capable of dissolving the binder resin. Whether or not the binder resin can be dissolved depends on the constituent components of the binder resin, molecular chain length, degree of three-dimensionality, etc., and therefore cannot be stated definitively. However, generally, hydrocarbons such as toluene, xylene, and hexane; halogenated hydrocarbons such as methylene chloride, chloroform, dichloroethane, and dichloroethylene; alcohols or ethers such as ethanol, butanol, benzyl alcohol ethyl ether, benzyl alcohol isopropyl ether, tetrahydrofuran, and tetrahydropyran; esters such as methyl acetate, ethyl acetate, butyl acetate, and isopropyl acetate; ketones or acetals such as acetone, methyl ethyl ketone, diisobutyl ketone, dimethyl oxide, diacetone alcohol, cyclohexanone, and methylcyclohexanone are used.

[0171] These solvents dissolve the binder resin and do not need to dissolve the colorants and other components. The colorants and other components only need to be dispersed in the binder resin solution. There is no limit to the amount of solvent used, but it should have a viscosity that allows granulation in an aqueous medium. A ratio of 10 / 90 to 50 / 50 (mass ratio of the former to the latter) of the material containing the binder resin, colorants, and other components (the former) to the solvent (the latter) is preferable in terms of ease of granulation and the yield of final toner particles.

[0172] The liquid (toner mother liquor) containing the binder resin, colorant, and other components dissolved or dispersed in the solvent is granulated in an aqueous medium containing an inorganic dispersant to a predetermined particle size. The aqueous medium is mainly water. The mixing ratio of the aqueous medium to the toner mother liquor is preferably aqueous medium / mother liquor = 90 / 10 to 50 / 50 (mass ratio). The inorganic dispersant is preferably selected from tricalcium phosphate, hydroxyapatite, calcium carbonate, titanium dioxide, and silica powder. The amount of inorganic dispersant used is determined according to the particle size of the granulated particles, but generally, it is preferably used in a range of 0.1% by mass to 15% by mass relative to the toner mother liquor. Using less than 0.1% by mass may result in poor granulation, while using more than 15% by mass may generate unnecessary fine particles, making it difficult to obtain the desired particles in high yield.

[0173] To properly granulate the toner mother liquor in an aqueous medium containing an inorganic dispersant, an auxiliary agent may be added to the aqueous medium. Such auxiliary agents include known cationic, anionic, and nonionic surfactants, with anionic surfactants being particularly preferred. For example, sodium alkylbenzenesulfonate, sodium α-olefin sulfonate, sodium alkylsulfonate, etc., are available in amounts of 1 × 10⁻⁶ relative to the toner mother liquor. -4 It is preferable that it be used in a range of 0% by mass or more and 0.1% by mass or less.

[0174] Granulation of the toner mother liquor in an aqueous medium containing an inorganic dispersant is preferably carried out under shearing conditions. The toner mother liquor dispersed in the aqueous medium is preferably granulated to have an average particle size of 20 μm or less. Particularly preferred is a size of 3 μm to 15 μm. Various dispersers are available that are equipped with a shearing mechanism, and among them, homogenizers are preferred. By using a homogenizer, substances that are incompatible with each other (in this embodiment, an aqueous medium containing an inorganic dispersant and a toner mother liquor) can be passed through the gap between the casing and the rotating rotor, thereby dispersing substances incompatible with a liquid into particulate form. Examples of such homogenizers include the TK Homomixer, Lineflow Homomixer, Autohomomixer (all manufactured by Tokushu Kika Kogyo Co., Ltd.), Silverson Homogenizer (manufactured by Silverson), and Polytron Homogenizer (manufactured by KINEMATICA AG).

[0175] The stirring conditions using a homogenizer are preferably such that the peripheral speed of the rotor blades is 2 m / second or more. Below this speed, particle formation tends to be insufficient. In this embodiment, the toner mother liquor is granulated in an aqueous medium containing an inorganic dispersant, and then the solvent is removed. Solvent removal may be carried out at room temperature (25°C) and atmospheric pressure, but since it takes a long time to remove, it is preferable to carry it out at a temperature lower than the boiling point of the solvent and within a range where the difference from the boiling point is 80°C or less. The pressure may be atmospheric pressure or reduced pressure, but when reduced pressure is used, it is preferable to use a pressure of 20 mmHg or more and 150 mmHg or less.

[0176] In this embodiment, it is preferable to wash with hydrochloric acid or the like after solvent removal. This removes any inorganic dispersant remaining on the surface of the toner particles, restoring the toner particles to their original composition and improving their properties. Then, dehydration and drying yield powdered toner particles. Similar to the agglomeration method, inorganic oxides such as silica, titania, and aluminum oxide are added to toner particles obtained by the dissolution suspension method as external additives for purposes such as charge adjustment, fluidity enhancement, and charge exchange. In addition to the inorganic oxides mentioned above, other components (particles) such as charge control agents, organic particles, lubricants, and abrasives may also be added as external additives.

[0177] In this embodiment, to set the average ratio b / a for the bright toner particles to a range of 0.5 to 0.8, methods include adjusting the amount of binder resin used for the metal pigment and the heating time during the fusion process in the case of the agglomeration method. For example, increasing the amount of binder resin used for the metal pigment makes it easier to increase the average ratio b / a for the toner particles. Also, increasing the heating time during the fusion process makes it easier to increase the average ratio b / a for the toner particles. Furthermore, the ratio b / a can be adjusted to a preferred range by the stirring conditions in the agglomeration process. More specifically, the ratio b / a can be reduced by stirring at high speed and heating at a constant temperature during the stage of forming agglomerated particles, and the ratio b / a can be increased by stirring at a lower speed and heating more. Furthermore, to adjust the ratio b / a to a preferred range, the toner particles may be processed by a ball mill. In this embodiment, to achieve a pigment area ratio in the range of 0.5 to 0.7, methods include adjusting the average equivalent circle diameter of the metal pigment, the amount of binder resin used for the metal pigment, and the heating time during the fusion process in the case of the agglomeration method. For example, increasing the average equivalent circle diameter of the metal pigment increases the pigment area ratio. Increasing the amount of binder resin used for the metal pigment makes it easier to decrease the pigment area ratio. Increasing the heating time during the fusion process also makes it easier to increase the pigment area ratio.

[0178] <Electrostatic Image Developer> The electrostatic image developer used in this embodiment contains at least the toner of this embodiment. The electrostatic image developer used in this embodiment may be a one-component developer containing only the toner of this embodiment, or it may be a two-component developer in which the toner and carrier are mixed.

[0179] The carrier is not particularly limited, and known carriers can be mentioned. Examples of the carrier include a coated carrier in which a coating resin is coated on the surface of a core material made of magnetic powder; a magnetic powder-dispersed carrier in which magnetic powder is dispersed and blended in a matrix resin; a resin-impregnated carrier in which porous magnetic powder is impregnated with resin; and the like. In addition, the magnetic powder-dispersed carrier and the resin-impregnated carrier may be carriers in which the constituent particles of the carrier are used as a core material and coated with a coating resin.

[0180] Examples of the magnetic powder include magnetic metals such as iron, nickel, and cobalt, and magnetic oxides such as ferrite and magnetite. Particularly, magnetite and ferrite are preferable. The magnetic powder may be used as particles dispersed in the resin.

[0181] Examples of the coating resin and the matrix resin include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic ester copolymer, straight silicone resin or its modified product composed of an organosiloxane bond, fluororesin, polyester, polycarbonate, phenol resin, epoxy resin, and the like. In addition, the coating resin and the matrix resin may contain other additives such as conductive particles.

[0182] [[ID=​​​​​​Specific resin coating methods include an immersion method in which the core material is immersed in a coating layer forming solution, a spray method in which the coating layer forming solution is sprayed onto the surface of the core material, a fluidized bed method in which the coating layer forming solution is sprayed in a state where the core material is suspended by flowing air, a kneader coater method in which the core material of the carrier and the coating layer forming solution are mixed in a kneader coater and the solvent is removed, and the like.

[0184] In the two-component developer, the mixing ratio (mass ratio) of the toner and the carrier is preferably toner:carrier = 1:100 to 30:100, and more preferably 3:100 to 20:100.

[0185] ≪Fixing device≫ The fixing device in the present embodiment is exemplified by, for example, a fixing device including a fixing member, a rotating body disposed in contact with the outer peripheral surface of the fixing member, and a pressing member disposed inside the fixing member and pressing the fixing member from the inner peripheral surface of the fixing member to the rotating body. And, as the fixing member, the fixing member in the present embodiment is applied.

[0186] Hereinafter, an example of the fixing device in the present embodiment will be shown while referring to the drawings.

[0187] (First Embodiment of Fixing Device) The first embodiment of the fixing device will be described with reference to FIG. 3. FIG. 3 is a schematic configuration diagram showing an example of the first embodiment of the fixing device (that is, the fixing device 60).

[0188] As shown in FIG. 3, the fixing device 60 includes, for example, a heating roll 61 (an example of a rotating body) that is rotationally driven, a pressure belt 62 (an example of a fixing member), and a pressure pad 64 (an example of a pressing member) that presses the heating roll 61 via the pressure belt 62. Note that the pressure pad 64 only needs to be such that, for example, the pressure belt 62 and the heating roll 61 are relatively pressurized. Therefore, the pressure belt 62 side may be pressurized to the heating roll 61, or the heating roll 61 side may be pressurized to the pressure belt 62.

[0189] A halogen lamp 66 (an example of a heating device) is installed inside the heating roll 61. The heating means is not limited to a halogen lamp; other heat-generating components may also be used.

[0190] Meanwhile, a temperature-sensing element 69 is positioned in contact with the surface of the heating roll 61. Based on the temperature measured by this temperature-sensing element 69, the illumination of the halogen lamp 66 is controlled to maintain the surface temperature of the heating roll 61 at a target set temperature (for example, 170°C).

[0191] The pressure belt 62 is rotatably supported, for example, by an internally positioned pressure pad 64 and a belt travel guide 63. In the clamping region N (nip portion), it is pressed against the heating roll 61 by the pressure pad 64.

[0192] The pressure pad 64 is positioned, for example, inside the pressure belt 62, and is pressed against the heating roll 61 via the pressure belt 62, forming a clamping area N between it and the heating roll 61. The pressing pad 64 includes, for example, a front clamping member 64a positioned on the entrance side of the clamping area N to secure a wide clamping area N, and a peeling clamping member 64b positioned on the exit side of the clamping area N to impart distortion to the heating roll 61.

[0193] To reduce the sliding resistance between the inner circumferential surface of the pressure belt 62 and the pressure pad 64, for example, a sheet-like sliding member 68 is provided on the surfaces of the front clamping member 64a and the peeling clamping member 64b that are in contact with the pressure belt 62. The pressure pad 64 and the sliding member 68 are held together by a metal retaining member 65.

[0194] For example, a belt travel guide 63 is attached to the holding member 65, and the pressure belt 62 rotates within it.

[0195] The heating roll 61 rotates in the direction of arrow S by, for example, a drive motor (not shown), and the pressure belt 62 rotates in the direction of arrow R, opposite to the direction of rotation of the heating roll 61, in accordance with this rotation. That is, for example, while the heating roll 61 rotates clockwise in Figure 3, the pressure belt 62 rotates counterclockwise.

[0196] Then, the paper K (an example of a recording medium) having an unfixed toner image is guided, for example, by a fuser entrance guide 56 and transported to the sandwiching area N. As the paper K passes through the sandwiching area N, the unfixed toner image on the paper K is fixed by the pressure and heat acting on the sandwiching area N.

[0197] In the fixing device 60, for example, a concave front clamping member 64a that conforms to the outer surface of the heating roll 61 ensures a wider clamping area N compared to a configuration without the front clamping member 64a.

[0198] Furthermore, the fixing device 60 is configured such that, for example, the peeling and clamping member 64b is positioned to protrude from the outer surface of the heating roll 61, thereby increasing the localized distortion of the heating roll 61 in the exit region of the clamping region N.

[0199] By arranging the peeling and clamping member 64b in this manner, for example, when the fixed paper K passes through the peeling and clamping region, it will pass through a locally large amount of strain, making it easier for the paper K to peel off from the heating roll 61.

[0200] As an auxiliary means for peeling, for example, a peeling member 70 is provided downstream of the clamping area N of the heating roll 61. The peeling member 70 is held by a holding member 72 in a position where the peeling claws 71 are in close proximity to the heating roll 61 in a direction opposite to the rotation direction of the heating roll 61 (counter direction).

[0201] (Second embodiment of the fixing device) A second embodiment of the fixing device will be described with reference to Figure 4. Figure 4 is a schematic diagram showing an example of the second embodiment of the fixing device (i.e., fixing device 410). As shown in FIG. 4, the fixing device 410 has a pressing part 414 and a heating part 430 facing the pressing part 414.

[0202] The pressing part 414 has a cylindrical roll member 412 (an example of a rotating body), is provided to face the heating part 430, is pressed against the outer surface of the heating belt 432 of the heating part 430, and rotates by a driving device (not shown).

[0203] In the pressing part 414, the roll member 412 is a so-called soft roll having a shaft part 416 made of a metal material such as iron, stainless steel, or aluminum, an elastic layer 418 covering the shaft part 416, and a release layer 420 coated or applied to the elastic layer 418. The release layer 420 is formed of a material with excellent insulation and release properties, such as PFA.

[0204] In the pressing part 414, the roll member 412 is grounded, and is grounded from the shaft part 416 of the roll member 412 with the pressing part side resistor 422 interposed therebetween. By grounding the pressing part 414 with the pressing part side resistor 422 interposed therebetween, current leakage (leakage current) from the electrodes of the planar heating element 440 of the heating part 430 is suppressed.

[0205] In the pressing part 414, the roll member 412 is pressed against the heating part 430 by a pressing member (not shown) made of an elastic body such as a coil spring. This pressing member has, for example, one end attached to the shaft part 416 and the other end attached to the main body of the image forming apparatus.

[0206] The heating part 430 has a heating belt 432 (an example of a fixing member), a planar heating element 440 as a heating member that heats the heating belt 432 from the inner peripheral surface side inside the heating belt 432, a holding member 434 that holds the planar heating element 440, and a frame member 452 that supports the holding member 434. At this time, the holding member 434 is supported by the frame member 452 and has a structure that can withstand the pressing from the pressing part 414. A unit consisting of a planar heating element 440, a holding member 434, and a frame member 452 is an example of a pressing member.

[0207] In the heating section 430, circular support members (not shown) are provided at both ends of the heating belt 432 in the longitudinal direction, to support the heating belt 432. A heating member gear (not shown) is provided on each support member to rotate the heating belt 432, and one end of this heating member gear is connected to a drive device (not shown), such as a motor, inside the main body of the image forming apparatus. The heating belt 432 is rotated.

[0208] In the heating section 430, the planar heating element 440, which serves as a heat-generating component, is formed, for example, as a long plate-like body along the longitudinal direction of the heating section 430, and has an electrically insulating base material, an insulating layer made of a polyimide-based heat-resistant resin, a pair of electrodes for power supply, and a resistive heating element, for example, made of stainless steel, which generates heat when power is supplied from these electrodes. The electrodes and the resistive heating element are connected by a power supply unit, and the electrodes, power supply unit, and resistive heating element are embedded in the insulating layer. The electrodes of the planar heating element 440 are grounded with the heating section side resistor 462 in between.

[0209] In the heating section 430, the holding member 434 is made of a resin material such as LCP (liquid crystal polymer), which has high heat resistance, and a groove 436 for holding the planar heating element 440 is formed along the longitudinal direction on the side facing the pressurizing section 414.

[0210] The holding member 434, while holding the planar heating element 440 in the groove 436, is pressed by the pressurizing section 414, thereby forming a pressing region 470.

[0211] In the heating section 430, the frame member 452 is made of, for example, a metal material and supports the holding member 434. Both ends of the frame member 452 are fixed to support members (not shown), so that the holding member 434 can withstand pressure from the pressurizing section 414. The heating section 430 may also be equipped with a thermistor or the like for temperature detection.

[0212] In the fixing device 410 described above, a pressing region 470 is formed by the roll member 412 of the pressurizing section 414 and the unit consisting of the planar heating element 440, holding member 434 and frame member 452 of the heating section 430, sandwiching the heating belt 432. By passing the recording medium holding the unfixed toner image through this pressing region 470, heat and pressure are applied to fix the unfixed toner image to the recording medium.

[0213] Image forming apparatus Next, the image forming apparatus according to this embodiment will be described. The image forming apparatus according to this embodiment comprises an image holder, a charging device for charging the surface of the image holder, a latent image forming device for forming a latent image on the charged surface of the image holder, a developing device for developing the latent image with toner to form a toner image, a transfer device for transferring the toner image to a recording medium, and a fixing device for fixing the toner image to the recording medium. The fixing device in this embodiment is then applied as the fixing device.

[0214] Here, in the image forming apparatus according to this embodiment, the fixing device may be made into a cartridge that can be attached to and detached from the image forming apparatus. In other words, the image forming apparatus according to this embodiment is The reactor cartridge may include the fixing device described in this embodiment as a component of the cartridge.

[0215] The image forming apparatus according to this embodiment will be described below with reference to the drawings. Figure 5 is a schematic diagram showing an example of an image forming apparatus according to this embodiment.

[0216] As shown in Figure 5, the image forming apparatus 100 according to this embodiment is, for example, an intermediate transfer type image forming apparatus generally called a tandem type, and comprises a plurality of image forming units 1Y, 1M, 1C, and 1K in which toner images of each color component are formed by an electrophotographic method; a primary transfer unit 10 that sequentially transfers (primary transfer) the toner images of each color component formed by each image forming unit 1Y, 1M, 1C, and 1K onto an intermediate transfer belt 15; a secondary transfer unit 20 that transfers (secondary transfer) the superimposed toner images transferred onto the intermediate transfer belt 15 onto a recording medium, paper K; and a fixing device 60 that fixes the secondary transferred image onto the paper K. The image forming apparatus 100 also has a control unit 40 that controls the operation of each device (each part).

[0217] This fixing device 60 is the first embodiment of the fixing device described above. The image forming apparatus 100 may also be configured to include the second embodiment of the fixing device described above.

[0218] Each image forming unit 1Y, 1M, 1C, and 1K of the image forming apparatus 100 is equipped with a photoreceptor 11 that rotates in the direction of arrow A, as an example of an image holder that holds the toner image formed on its surface.

[0219] Around the photoreceptor 11, a charger 12 is provided as an example of a charging means for charging the photoreceptor 11, and a laser exposure unit 13 (indicated by the symbol Bm in the figure) is provided as an example of a latent image forming means for writing an electrostatic latent image onto the photoreceptor 11.

[0220] Furthermore, surrounding the photoreceptor 11, as an example of a developing means, is a developer 14 which contains toners for each color component and visualizes the electrostatic latent image on the photoreceptor 11 using the toner, and a primary transfer roll 16 which transfers the toner images for each color component formed on the photoreceptor 11 to an intermediate transfer belt 15 in a primary transfer unit 10.

[0221] Furthermore, a photoreceptor cleaner 17 is provided around the photoreceptor 11 to remove any residual toner on the photoreceptor 11, and the electrophotographic devices, including the charger 12, laser exposure unit 13, developer unit 14, primary transfer roll 16, and photoreceptor cleaner 17, are sequentially arranged along the rotational direction of the photoreceptor 11. These image forming units 1Y, 1M, 1C, and 1K are arranged in a substantially straight line from the upstream side of the intermediate transfer belt 15 in the order of yellow (Y), magenta (M), cyan (C), and black (K).

[0222] The intermediate transfer belt 15, which is an intermediate transfer material, is a film-like pressure belt with a resin such as polyimide or polyamide as the base layer and containing an appropriate amount of an antistatic agent such as carbon black. Its volume resistivity is 10 6 Ωcm or more 10 14 It is formed to be less than or equal to Ωcm, and its thickness is, for example, about 0.1 mm.

[0223] The intermediate transfer belt 15 is driven (rotated) in a circulating manner in direction B shown in Figure 5 at a speed appropriate for the purpose by various rolls. These various rolls include a drive roll 31 that rotates the intermediate transfer belt 15 by a motor (not shown) with excellent constant-speed performance, a support roll 32 that supports the intermediate transfer belt 15 which extends substantially linearly along the arrangement direction of each photoreceptor 11, a tension-applying roll 33 that applies tension to the intermediate transfer belt 15 and functions as a corrective roll to prevent the intermediate transfer belt 15 from meandering, a back roll 25 provided in the secondary transfer section 20, and a cleaning back roll 34 provided in the cleaning section that scrapes off residual toner on the intermediate transfer belt 15.

[0224] The primary transfer section 10 consists of a primary transfer roll 16 positioned opposite the photoreceptor 11, with an intermediate transfer belt 15 in between. The primary transfer roll 16 consists of a core and a sponge layer, which is an elastic layer fixed around the core. The core is a cylindrical rod made of metal such as iron or stainless steel. The sponge layer is made of a blend of NBR, SBR, and EPDM rubber containing a conductive material such as carbon black, and has a volume resistivity of 10 7.5Ωcm or more 10 8.5 It is a sponge-like cylindrical roll with a diameter of Ωcm or less.

[0225] The primary transfer roll 16 is then pressed against the photoreceptor 11 with the intermediate transfer belt 15 in between, and a voltage (primary transfer bias) with the opposite polarity to the charge polarity of the toner (negative polarity; the same applies hereinafter) is applied to the primary transfer roll 16. As a result, the toner images on each photoreceptor 11 are sequentially electrostatically attracted to the intermediate transfer belt 15, and superimposed toner images are formed on the intermediate transfer belt 15.

[0226] The secondary transfer section 20 comprises a back roll 25 and a secondary transfer roll 22 positioned on the toner image holding surface side of the intermediate transfer belt 15.

[0227] The back roll 25 has a surface made of a blend of EPDM and NBR rubber with dispersed carbon, and the inside is made of EPDM rubber. Its surface resistivity is 10 7 Ω / □ or more 10 10 It is formed to be less than or equal to Ω / □, and its hardness is set to, for example, 70° (Asker C: manufactured by Polymer Instruments, the same applies hereafter). This back roll 25 is positioned on the back side of the intermediate transfer belt 15 and constitutes the opposing electrode of the secondary transfer roll 22, and is in contact with a metal power supply roll 26 to which the secondary transfer bias is stably applied.

[0228] On the other hand, the secondary transfer roll 22 consists of a core and a sponge layer as an elastic layer fixed around the core. The core is a cylindrical rod made of metal such as iron or stainless steel. The sponge layer is made of a blend of NBR, SBR, and EPDM rubber containing conductive materials such as carbon black, and has a volume resistivity of 10 7.5 Ωcm or more 10 8.5 It is a sponge-like cylindrical roll with a diameter of Ωcm or less.

[0229] The secondary transfer roll 22 is then pressed against the back roll 25 with the intermediate transfer belt 15 in between, and the secondary transfer roll 22 is grounded to form a secondary transfer bias between itself and the back roll 25, thereby secondary transferring the toner image onto the paper K that is transported to the secondary transfer section 20.

[0230] Furthermore, an intermediate transfer belt cleaner 35 is provided downstream of the secondary transfer section 20 of the intermediate transfer belt 15, so as to be able to move toward and away from the intermediate transfer belt 15. This cleaner removes residual toner and paper dust from the intermediate transfer belt 15 after secondary transfer and cleans the surface of the intermediate transfer belt 15.

[0231] The intermediate transfer belt 15, the primary transfer section 10 (primary transfer roll 16), and the secondary transfer section 20 (secondary transfer roll 22) are examples of transfer means.

[0232] Meanwhile, upstream of the yellow image forming unit 1Y, a reference sensor (home position sensor) 42 is provided that generates a reference signal, which serves as a reference for determining the image forming timing in each image forming unit 1Y, 1M, 1C, and 1K. This reference sensor 42 recognizes a mark provided on the back side of the intermediate transfer belt 15 and generates a reference signal. Based on the recognition of this reference signal, each image forming unit 1Y, 1M, 1C, and 1K is configured to start image forming according to instructions from the control unit 40. Furthermore, an image density sensor 43 for image quality adjustment is located downstream of the black image forming unit 1K.

[0233] Furthermore, the image forming apparatus according to this embodiment includes, as a means for transporting paper K, a paper storage section 50 for storing paper K, a paper feed roll 51 for taking out and transporting the paper K accumulated in the paper storage section 50 at a predetermined timing, a transport roll 52 for transporting the paper K fed out by the paper feed roll 51, a transport guide 53 for sending the paper K transported by the transport roll 52 to the secondary transfer section 20, a transport belt 55 for transporting the paper K that has been secondarily transferred by the secondary transfer roll 22 to the fixing device 60, and a fixing inlet guide 56 for guiding the paper K to the fixing device 60.

[0234] Next, the basic image formation process of the image forming apparatus according to this embodiment will be described. In the image forming apparatus according to this embodiment, image data output from an image reading device (not shown) or a personal computer (PC) (not shown) is processed by an image processing device (not shown), and then image formation is performed by image forming units 1Y, 1M, 1C, and 1K.

[0235] The image processing device performs various image processing operations on the input image data, including shading correction, positional shift correction, brightness / color space conversion, gamma correction, frame removal, color editing, and movement editing. The processed image data is converted into four-color chromatic data (Y, M, C, K) and output to the laser exposure unit 13.

[0236] In the laser exposure unit 13, according to the input color tone data, an exposure beam Bm emitted from, for example, a semiconductor laser is irradiated onto each of the photoreceptors 11 of the image forming units 1Y, 1M, 1C, and 1K. After the surface of each photoreceptor 11 of the image forming units 1Y, 1M, 1C, and 1K is charged by the charger 12, the surface is scanned and exposed by the laser exposure unit 13, and an electrostatic latent image is formed. The formed electrostatic latent image is then developed as toner images of the respective colors Y, M, C, and K by the respective image forming units 1Y, 1M, 1C, and 1K.

[0237] The toner images formed on the photoreceptors 11 of the image forming units 1Y, 1M, 1C, and 1K are transferred onto the intermediate transfer belt 15 in the primary transfer section 10, where each photoreceptor 11 comes into contact with the intermediate transfer belt 15. More specifically, in the primary transfer section 10, a primary transfer roll 16 applies a voltage (primary transfer bias) with the opposite polarity to the toner's charge polarity (negative polarity) to the substrate of the intermediate transfer belt 15, and the toner images are sequentially superimposed on the surface of the intermediate transfer belt 15 to perform primary transfer.

[0238] After the toner image is sequentially transferred to the surface of the intermediate transfer belt 15, the intermediate transfer belt 15 moves and the toner image is transported to the secondary transfer section 20. When the toner image is transported to the secondary transfer section 20, the transport mechanism rotates the paper feed roll 51 in time with the transport of the toner image to the secondary transfer section 20, and paper K of the desired size is supplied from the paper storage section 50. The paper K supplied by the paper feed roll 51 is transported by the transport roll 52 and reaches the secondary transfer section 20 via the transport guide 53. Before reaching the secondary transfer section 20, the paper K is temporarily stopped, and the position of the paper K and the position of the toner image are aligned by rotating the alignment roll (not shown) in time with the movement of the intermediate transfer belt 15 holding the toner image.

[0239] In the secondary transfer section 20, the secondary transfer roll 22 is pressed against the back roll 25 via the intermediate transfer belt 15. At this time, the paper K, which has been transported in sync with the timing, is sandwiched between the intermediate transfer belt 15 and the secondary transfer roll 22. When a voltage (secondary transfer bias) of the same polarity as the charge polarity (negative polarity) of the toner is applied from the power supply roll 26, a transfer electric field is formed between the secondary transfer roll 22 and the back roll 25. The unfixed toner image held on the intermediate transfer belt 15 is then transferred by the secondary transfer roll 22 and the back roll 25. In the secondary transfer section 20, which is pressurized, the material is electrostatically transferred onto the paper K all at once.

[0240] Subsequently, the paper K on which the toner image has been electrostatically transferred is peeled off the intermediate transfer belt 15 by the secondary transfer roll 22 and transported to the transport belt 55 located downstream of the secondary transfer roll 22 in the paper transport direction. The transport belt 55 transports the paper K to the fuser 60 at an optimal transport speed for the fuser 60. The unfixed toner image on the paper K transported to the fuser 60 is fixed to the paper K by the fuser 60 through a fixing process using heat and pressure. The paper K with the fixed image then transported to the paper discharge and storage section (not shown) located in the discharge section of the image forming apparatus.

[0241] Meanwhile, after the transfer to paper K is completed, any residual toner remaining on the intermediate transfer belt 15 is transported to the cleaning section as the intermediate transfer belt 15 rotates, and is removed from the intermediate transfer belt 15 by the cleaning back roll 34 and the intermediate transfer belt cleaner 35.

[0242] Although this embodiment has been described above, it is not intended to be interpreted as being limited to the above embodiment, and various modifications, changes, and improvements may be made. [Examples]

[0243] The embodiment will be described in more detail below with reference to examples, but this embodiment is not limited to the following examples. In the following description, unless otherwise specified, "parts" and "%" all refer to mass.

[0244] [Example 1] -Preparation of the developer- <Preparation of Metal Pigment Dispersion> • Aluminum pigment (manufactured by Showa Aluminum Powder Co., Ltd., 2173EA): 100 units Anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen®): 1.5 parts • Ion-exchanged water: 400 bottles The solvent was removed from the aluminum pigment paste, and the pigment was mechanically pulverized and classified using a Star Mill (Ashizawa Finetech Co., Ltd., LMZ). Then, it was mixed with the above-mentioned activator and deionized water, and dispersed for about 1 hour using an emulsifying disperser Cavitron (Taiheiyo Kiko Co., Ltd., CR1010) to prepare a metal pigment dispersion (solid content concentration: 20%) in which metal pigment particles (aluminum pigment) were dispersed. The average equivalent circle diameter of the dispersion was 15 μm.

[0245] <Synthesis of amorphous polyester resin> • Bisphenol A ethylene oxide 2.2 molar adduct: 40 mol% • Bisphenol A propylene oxide 2.2 molar adduct: 60 mol% Terephthalic acid: 47 mol% • Fumaric acid: 40 mol% Dodecenyl succinic anhydride: 15 mol% • Trimellitus anhydride: 3 mol%

[0246] In a reaction vessel equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet tube, all monomer components except fumaric acid and trimellitic anhydride, along with 0.25 parts of tin dioctanoate per 100 parts of the total monomer components, were added. The mixture was reacted at 235°C for 6 hours under a nitrogen gas stream, then cooled to 200°C, and the fumaric acid and trimellitic anhydride were added and reacted for 1 hour. The temperature was further increased to 220°C over 4 hours, and polymerization was carried out under a pressure of 10 kPa until the desired molecular weight was obtained, yielding a pale yellow, transparent amorphous polyester resin. The obtained amorphous polyester resin had a glass transition temperature (Tg) of 59°C determined by DSC, a mass-average molecular weight (Mw) of 25,000 determined by GPC, a number-average molecular weight (Mn) of 7,000, a softening temperature of 107°C determined by a flow tester, and an acid value (AV) of 13 mg KOH / g.

[0247] <Preparation of amorphous polyester resin dispersion> A 3-liter jacketed reaction vessel (manufactured by Tokyo Rikakikai Co., Ltd.: BJ-30N), equipped with a condenser, thermometer, water dropper, and anchor blades, was maintained at 40°C in a water-circulating constant-temperature bath. A mixed solvent of 160 parts ethyl acetate and 100 parts isopropyl alcohol was added to the reaction vessel, and 300 parts of the amorphous polyester resin were added to this mixture. The mixture was stirred at 150 rpm using a three-one motor to dissolve the resin and obtain an oil phase. 14 parts of a 10% aqueous ammonia solution were added to this stirred oil phase over a dropwise time of 5 minutes, and after mixing for 10 minutes, 900 parts of deionized water were added dropwise at a rate of 7 parts per minute to invert the phase and obtain an emulsion. Immediately, 800 parts of the obtained emulsion and 700 parts of deionized water were placed in a 2-liter round-bottom flask and set in an evaporator (Tokyo Rikakikai Co., Ltd.) equipped with a vacuum control unit via a trap bulb. While rotating the round-bottom flask, it was heated in a 60°C water bath, and the pressure was reduced to 7 kPa while taking care to prevent bumping, to remove the solvent. When the amount of recovered solvent reached 1,100 parts, the pressure was returned to atmospheric pressure, and the round-bottom flask was cooled with water to obtain the dispersion. The obtained dispersion had no solvent odor. The volume-average particle size D50 of the resin particles in this dispersion was 130 nm. In the following, the volume-average particle size D50 was the average of three measurements taken with Microtrac, excluding the maximum and minimum values ​​out of five measurements. Subsequently, deionized water was added to adjust the solid content to 20%, and this was obtained as an amorphous polyester resin dispersion.

[0248] <Synthesis of crystalline polyester resin> • 1,10-Dodecanedioic acid: 50 mol% • 1,9-nonanediol: 50 mol% The above monomer components were placed in a reaction vessel equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet tube. After replacing the reaction vessel with dry nitrogen gas, 0.25 parts of titanium tetrabutoxide (reagent) were added per 100 parts of the monomer components. The reaction was stirred at 170°C for 3 hours under a nitrogen gas stream, then the temperature was further increased to 210°C over 1 hour. The pressure inside the reaction vessel was reduced to 3 kPa, and the reaction was stirred under reduced pressure for 13 hours to obtain a crystalline polyester resin. The obtained crystalline polyester resin had a melting temperature of 73.6°C by DSC, a mass-average molecular weight Mw of 25,000 by GPC, a number-average molecular weight Mn of 10,500, and an acid value AV of 10.1 mgKOH / g.

[0249] <Preparation of crystalline polyester resin dispersion> In a 3-liter jacketed reaction vessel (manufactured by Tokyo Rikakikai Co., Ltd.: BJ-30N) equipped with a condenser, thermometer, water dropper, and anchor blades, 300 parts of the crystalline polyester resin, 160 parts of methyl ethyl ketone (solvent), and 100 parts of isopropyl alcohol (solvent) were placed. The resin was dissolved while stirring at 100 rpm in a water-circulating constant-temperature bath while maintaining the temperature at 70°C (solution preparation step). The stirring speed was then increased to 150 rpm, the water circulation constant temperature bath was set to 66°C, 17 parts of 10% aqueous ammonia (reagent) were added over 10 minutes, and then 900 parts of deionized water, which had been kept at 66°C, were added dropwise at a rate of 7 parts / minute to invert the phase and obtain an emulsion. Immediately, 800 parts of the resulting emulsion and 700 parts of deionized water were placed in a 2-liter round-bottom flask and set in an evaporator (Tokyo Rikakikai Co., Ltd.) equipped with a vacuum control unit via a trap bulb. While rotating the round-bottom flask, it was heated in a 60°C water bath, and the pressure was reduced to 7 kPa while taking care to prevent bumping, to remove the solvent. When the amount of recovered solvent reached 1,100 parts, the pressure was returned to atmospheric pressure, and the round-bottom flask was cooled with water to obtain the dispersion. The obtained dispersion had no solvent odor. The volume-average particle size D of the resin particles in this dispersion. 50 The wavelength was 130 nm. Subsequently, deionized water was added to adjust the solid content to 20%, and this was used as a crystalline polyester resin dispersion.

[0250] <Toner production> • Amorphous polyester resin dispersion: 263 parts • Crystalline polyester resin dispersion: 12 parts • Metallic pigment dispersion: 100 parts Nonionic surfactant (IGEPAL CA897): 2.5 parts

[0251] The above raw materials were placed in a 2L cylindrical stainless steel container and mixed by homogenizing them for 10 minutes at 4000 rpm while applying shear force using a homogenizer (IKA Ultra-Turrax T50). Next, 60 parts of a 10% nitric acid aqueous solution of polyaluminum chloride were gradually added dropwise as a flocculant, and the homogenizer was rotated at 5000 rpm for 15 minutes to disperse and mix the materials to obtain the raw material dispersion. Subsequently, the raw material dispersion was transferred to a polymerization vessel equipped with a stirring device using two paddle blades and a thermometer. The stirring speed was set to 857 rpm and heating was started with a mantle heater to promote the growth of aggregated particles at 54°C. At this time, the pH of the raw material dispersion was controlled to a range of 2.2 to 3.5 using 0.3N nitric acid or 1N sodium hydroxide aqueous solution. The mixture was maintained at this pH range for about 2 hours to form aggregated particles.

[0252] Next, 125 parts of amorphous polyester resin dispersion were added to adhere the resin particles of the binder resin to the surface of the aggregated particles. Subsequently, the temperature was raised to 56°C, and the aggregated particles were sorted while checking the particle size and morphology using an optical microscope and a Multisizer II. Then, 4.25 parts of a chelating agent (HIDS, manufactured by Nippon Shokubai Co., Ltd.) were added, and the pH was adjusted to 7.8 using a 5% sodium hydroxide aqueous solution and held for 15 minutes. After that, the pH was raised to 8.0 to fuse the aggregated particles, and the temperature was raised to 66.5°C. After confirming that the aggregated particles had fused using an optical microscope, the pH was lowered to 6.0 while maintaining the temperature at 66.5°C, heating was stopped after 1 hour, and the mixture was cooled at a rate of 1.0°C / min. After that, the mixture was sieved with a 20 μm mesh, washed with water repeatedly, and dried in a vacuum dryer to obtain toner particles. The volume-average particle diameter of the obtained toner particles was 17.2 μm, the average ratio b / a was 0.5, and the pigment area ratio was 0.7. For every 100 parts of toner particles, 1.5 parts of silica particles (RY50, manufactured by Nippon Aerosil Co., Ltd.) were mixed using a Henschel mixer (manufactured by Mitsui Miike Co., Ltd.) at a peripheral speed of 30 m / s for 3 minutes. The mixture was then sieved using a vibrating sieve with a mesh size of 45 μm to produce toner.

[0253] <Career Creation> • Ferrite particles (volume-average particle size: 35 μm): 100 units • Toluene: 14 parts • Perfluoroacrylate copolymer (critical surface tension: 24 dyn / cm): 1.6 parts • Carbon black (product name: VXC-72, manufactured by Cabot, volume resistivity: 100 Ωcm or less): 0.12 parts · Crosslinked melamine resin particles (average particle diameter: 0.3 μm, insoluble in toluene): 0.3 part

[0254] First, carbon black was diluted with toluene and added to the perfluoroacrylate copolymer, and then dispersed with a sand mill. Next, each of the above components other than the ferrite particles was dispersed with a stirrer for 10 minutes to prepare a coating layer forming solution. Then, this coating layer forming solution and the ferrite particles were put into a vacuum degassing kneader, stirred at a temperature of 60 °C for 30 minutes, and then the pressure was reduced to distill off toluene to form a resin coating layer and obtain a carrier.

[0255] <Preparation of developer> The toner: 36 parts and the carrier: 414 parts were put into a 2-liter V blender, stirred for 20 minutes, and then sieved with a 212 μm sieve to prepare a developer.

[0256] <00​​​​​​​​​​​​​​​​​​​​​​​​​​On a base material made of φ168 polyimide, X34-3160-A / B manufactured by Shin-Etsu Chemical Co., Ltd. was formed as an elastic layer so that the average film thickness became 400 μm. Next, as a surface layer, the coating material for the surface layer was formed on the elastic layer so that the average film thickness became 30 μm, and a fixing belt was obtained.

[0259] 〔Examples 2 to 5 and Comparative Examples 1 to 2〕 In Example 1, except that the amounts of SQ1: organopolysiloxane (T-type) having a silsesquioxane structure and dimethylorganopolysiloxane (D-type) used in the surface layer of the fixing belt were changed to the amounts shown in Table 1, a fixing belt was obtained in the same manner as in Example 1. Note that the developer used was the developer prepared in Example 1.

[0260] 〔Example 6〕 In Example 1, except that SQ1: organopolysiloxane (T-type) having a silsesquioxane structure used in the surface layer of the fixing belt was changed to the following SQ2, a fixing belt was obtained in the same manner as in Example 1. Note that the developer used was the developer prepared in Example 1. ·SQ2: Organopolysiloxane (T-type, manufactured by Konishi Chemical Co., Ltd., "SR-23", formula: [R 1 SiO 3 / 2 m Organopolysiloxane having only T units (in the formula, R 1 = phenyl group)) represented by

[0261] [[ID=3O]]Regarding the surface layer of the fixing belt obtained in each example, "the difference ΔH between the maximum value and the minimum value of the ultra-micro hardness" and "the tensile elongation rate" were measured. The results are shown in Table 1.

[0262] <Evaluation> The fixing belt obtained in each example was installed in a modified machine of an image forming apparatus DocuColor-7171P (manufactured by Fujifilm Business Innovation Corp.), and the above-mentioned developer was installed as a developer to obtain an image forming apparatus.

[0263] ·Toner offset​ Ten solid images were formed consecutively using the aforementioned image forming apparatus, and the presence or absence of toner smudges on both sides of the paper was observed. Toner smudges were evaluated according to the following criteria. -Evaluation Criteria- A: No smudging due to toner offset was observed. B: Toner offset stains were not visible to the naked eye, but were observed under magnification. C: Toner offset stains were visible to the naked eye.

[0264] • Luminousness and maintenance of luminosity Using the aforementioned image forming apparatus, 1000 solid images were formed in succession. For the first and 100th solid images, the luster was visually evaluated under color observation lighting (natural daylight illumination) in accordance with JIS K5600-4-3:1999 "General test methods for paints - Part 4: Visual properties of coatings - Section 3: Visual comparison of colors". The evaluation was based on the judgment of 10 subjects, and the evaluation criteria were as follows. -Evaluation Metric (Lusterity)- A: A group of 8 to 10 people were judged to have a radiant presence. B: Five to seven people judged to have a radiant presence. C: Six to seven people judged that there was no sense of brilliance. D: 8 to 10 people judged that there was no sense of brilliance.

[0265] Furthermore, the glossiness was evaluated for the first and 1000th solid color images as described above, and the glossiness retention was evaluated based on the difference in glossiness between the first and 1000th solid color images according to the following criteria. -Evaluation indicator (maintenance of luster)- A: There is no difference in the sense of brilliance. B: There is a difference in brightness in a portion of the solid image (an area of ​​5% to less than 50%). C: There is a difference in brightness on half of the solid image (an area of ​​50% to less than 90%). D: There is a difference in glossiness across the entire surface (over 90% of the area) of the solid image.

[0266] [Table 1]

[0267] The results shown in Table 1 indicate that, compared to the comparative example, the example yields images with higher brilliance when an image is formed using toner containing brilliance toner particles.

[0268] Preferred embodiments of the present invention are described below. << <1> >> Image holder and, A charging means for charging the surface of the image holder, A means for forming an electrostatic image on the surface of the charged image holder, A developing means for developing an electrostatic image developer containing toner, wherein the toner particles contain a metallic pigment having an average equivalent circular diameter of 5 μm or more and 15 μm or less, the average value of the ratio b / a of the major axis diameter a to the minor axis diameter b in the cross-section of the toner particles is 0.5 or more and 0.8 or less, and the average value of the area of ​​the metallic pigment in the projected image of the toner particles when viewed from the thickness direction is 0.5 or more and 0.7 or less, and developing means for developing an electrostatic image formed on the surface of the image holder as a toner image using the electrostatic image developer, A transfer means for transferring the aforementioned toner image to a recording medium, A fixing device comprising a fixing member having a surface layer having a surface layer in which the difference ΔH between the maximum and minimum ultramicrohardness values ​​when ultramicrohardness is measured at 50 arbitrary points according to the ultramicrohardness test specified in JIS Z2255 (2003), is 0 or more and 15 or less, and the surface layer of the fixing member is brought into contact with the toner image on the recording medium and heated and pressurized to fix the toner image on the recording medium, and An image forming apparatus comprising: Equation 1 [R1 SiO 3 / 2 ] m (In Equation 1, R 1 Each of these independently represents a hydrogen atom, alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group, and -C(=O)-CR 2 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, a methyl group, or an ethyl group. 2 If you have multiple R 2 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. m represents a positive integer. << <2> >> The aforementioned composition has a content ratio (Type T / Type D) of 3 / 7 or more and 7 / 3 or less. <1> The image forming apparatus described in >>. << <3> >> The surface layer has a difference ΔH between the maximum and minimum values ​​of the ultramicrohardness that is between 0 and 5. <1> >> or << <2> The image forming apparatus described in >>. << <4> >> The aforementioned surface layer has a tensile elongation of 100 or more. <1> >>~<< <3> An image forming apparatus as described in any one of the items >>. << <5> >> The aforementioned surface layer has a tensile elongation of 150 or more. <4> >>The image forming apparatus described. << <6> >> The aforementioned surface layer has an average value of 45% or less for the ratio B / A × 100 (%) of the amount of indentation when the load is released to the amount of indentation A when the load is applied in the ultra-microhardness test specified in JIS Z2255 (2003). <1> >>~<< <5> An image forming apparatus as described in any one of the items >>. << <7> >> The surface layer has an average value of 40% or less for the ratio B / A × 100 (%). <6> The image forming apparatus described in >>. << <8> >> The aforementioned R 1 At least one of them is a methyl group or a phenyl group. <1> >>~<< <7> An image forming apparatus as described in any one of the items >>. << <9> >> The aforementioned R 1 At least one of them is a methyl group. <8> The image forming apparatus described in >>. << <10> >> A charging step in which the surface of the image holder is charged, A step of forming an electrostatic image on the surface of the charged image holder, A developing step of developing an electrostatic image formed on the surface of an image holder as a toner image using an electrostatic image developer containing toner, wherein the toner particles contain a metal pigment having an average equivalent circular diameter of 5 μm or more and 15 μm or less, the average value of the ratio b / a of the major axis diameter a to the minor axis diameter b in the cross-section of the toner particles is 0.5 or more and 0.8 or less, and the average value of the area of ​​the metal pigment in the projected image of the toner particles when viewed from the thickness direction is 0.5 or more and 0.7 or less. A transfer step of transferring the toner image formed on the surface of the image holder to the surface of the recording medium, A fixing step in which a toner image is fixed to a recording medium by bringing the surface layer of a fixing member into contact with the toner image on the recording medium and applying heat and pressure, the fixing member having a surface layer having a surface layer having a surface layer where the difference ΔH between the maximum and minimum ultramicrohardness values ​​when the ultramicrohardness is measured at any 50 points according to the ultramicrohardness test specified in JIS Z2255 (2003) is 0 or more and 15 or less, and the surface layer of the fixing member is brought into contact with the toner image on the recording medium and the toner image is fixed to the recording medium, the fixing step is to fix the toner image to the recording medium, the fixing member having a surface layer having a surface layer where the difference ΔH between the maximum and minimum ultramicrohardness values ​​is 0 or more and 15 or less when the ultramicrohardness is measured at any 50 points according to the ultramicrohardness test specified in JIS Z2255 (2003), the surface layer of the fixing member is brought into contact with the toner image on the recording medium and the toner image is fixed to the recording medium, the fixing step is to fix the toner image to the recording medium, the fixing member having a surface layer having a surface layer having a surface layer where the difference ΔH between the maximum and minimum ultramicrohardness values ​​is 0 or more and 15 or less, the surface layer of the fixing member is brought into contact with the toner image on the recording medium, and the toner image is fixed to the recording medium, the fixing step is to fix the toner image to the recording medium, An image forming method having the following characteristics. Equation 1 [R 1 SiO 3 / 2 ] m (In Equation 1, R 1 Each of these independently represents a hydrogen atom, alkyl group, alkenyl group, alkynyl group, aralkyl group, aryl group, and -C(=O)-CR 2 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, a methyl group, or an ethyl group. 2 If you have multiple R 2 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. m represents a positive integer.

[0269] << <1> >><< <8> >> or << <9> According to the invention described above, compared to an image forming apparatus equipped with a fixing member having a surface layer which is a cured product of a composition with a content ratio (T-type / D-type) of less than 1 / 9 or greater than 9 / 1, or a surface layer in which the difference ΔH between the maximum and minimum values ​​of ultrafine hardness is greater than 15, an image forming apparatus is provided that can obtain an image with high brilliance when forming an image using toner containing brilliance toner particles. << <2> According to the invention described above, compared to an image forming apparatus equipped with a surface layer which is a cured product of a composition having a content ratio (Type T / Type D) of less than 3 / 7 or greater than 7 / 3, an image forming apparatus is provided that can obtain an image with high brilliance when forming an image using a toner containing brilliance toner particles. << <3> According to the invention described above, compared to an image forming apparatus equipped with a fixing member having a surface layer in which the difference ΔH between the maximum and minimum values ​​of ultra-micro hardness is greater than 5, an image forming apparatus is provided that can obtain an image with high brilliance when forming an image using toner containing brilliance toner particles. << <4> >> or << <5> According to the invention described above, compared to an image forming apparatus equipped with a fixing member having a surface layer with a tensile elongation of less than 100, an image forming apparatus is provided that can obtain an image with high brilliance when forming an image using toner containing brilliance toner particles. << <6> >> or << <7> According to the invention described above, compared to an image forming apparatus equipped with a fixing member in which the average value of the surface layer ratio B / A × 100 (%) exceeds 45%, an image forming apparatus is provided that can stably obtain images with high brilliance when continuously forming images with brilliance. << <10> According to the invention described above, compared to an image forming method in which the fixing process is performed using a fixing member having a surface layer which is a cured product of a composition with a content ratio (T-type / D-type) of less than 1 / 9 or greater than 9 / 1, or a surface layer in which the difference ΔH between the maximum and minimum values ​​of ultrafine hardness is greater than 15, an image forming method is provided in which an image can be formed using a toner containing lustrous toner particles and an image with high lustrousness is obtained. [Explanation of Symbols]

[0270] 1Y, 1M, 1C, 1K Image Forming Unit 10 Primary Transfer Section 11 Photoreceptor 12 Chargers 13. Laser exposure unit 14. Developer 15 Intermediate transfer belt 16 Primary transfer roll 17 Photoconductor Cleaner 20 Secondary transfer section 22 Secondary transfer roll 23. Luminous toner particles 24 Metallic Pigments 25 Back Roll 26 Power supply roll 31 Drive Roll 32 support rolls 33 Tension-applying roll 34 Cleaning back roll 35 Intermediate Transfer Belt Cleaner 40 Control Unit 42 Reference Sensor 43 Image density sensor 50 Paper storage compartments 51 Paper feed roll 52 Conveyor Rolls 53 Conveyor Guide 55 Conveyor belt 56 Fixing entrance guide 60 Fixing device 61 Heating Roll 62 Compression belt 63 Belt Drive Guide 64 Pressure Pads 64a Front clamping member 64b Peeling and clamping member 65 Retaining member 66 Halogen lamps 68 Sliding member 69 Temperature sensing element 70 Release Member 71. Detachable nails 72 Retaining member 100 Image forming apparatus 110 Fixing member 110A base material layer 110B Elastic layer 110C surface layer 410 Fixing device 412 Roll Member 414 Pressurized section 416 Shaft 418 Elastic layer 420 Release layer 422 Pressure-side resistor 430 Heating section 432 Heating belt 434 Retaining member 436 Groove 440 Planar heating element 452 Frame members 462 Heating section side resistor 470 Pressing area

Claims

1. Image holder and, A charging means for charging the surface of the image holder, A means for forming an electrostatic image on the surface of the charged image holder, A developing means for developing an electrostatic image developer containing toner, wherein the toner particles contain a metallic pigment having an average circular equivalent diameter of 5 μm or more and 15 μm or less, the average value of the ratio b / a of the major axis diameter a to the minor axis diameter b in the cross-section of the toner particles is 0.5 or more and 0.8 or less, and the average value of the area of ​​the metallic pigment in the projected image of the toner particles when viewed from the thickness direction is 0.5 or more and 0.7 or less, and developing means for developing an electrostatic image formed on the surface of the image holder as a toner image using the electrostatic image developer, A transfer means for transferring the aforementioned toner image to a recording medium, A fixing device comprising a fixing member having a surface layer having a surface layer in which the difference ΔH between the maximum and minimum ultramicrohardness values ​​0 to 15 when the ultramicrohardness is measured at 50 arbitrary points according to the ultramicrohardness test specified in JIS Z2255 (2003), and which fixes the toner image on the recording medium by bringing the surface layer of the fixing member into contact with the toner image on the recording medium and applying heat and pressure, and a fixing device comprising: An image forming apparatus comprising: Formula 1 [R] １ SiO ３／２ ] ｍ (In Equation 1, R １ Each of these independently consists of a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an aryl group, and -C(=O)-CR ２ 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 represents a hydrogen atom, a methyl group, or an ethyl group. R ２ When having a plurality of R ２ may be the same as 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. (m represents a positive integer.)

2. The image forming apparatus according to claim 1, wherein the content ratio (Type T / Type D) in the composition is 3 / 7 or more and 7 / 3 or less.

3. The image forming apparatus according to claim 1, wherein the surface layer has a difference ΔH between the maximum and minimum values ​​of the ultra-micro hardness of 0 or more and 5 or less.

4. The image forming apparatus according to claim 1, wherein the surface layer has a tensile elongation rate of 100 or more.

5. The image forming apparatus according to claim 4, wherein the surface layer has a tensile elongation rate of 150 or more.

6. The image forming apparatus according to claim 1, wherein the surface layer has an average value of 45% or less for the ratio B / A × 100 (%) of the amount of indentation when the load is released to the amount of indentation A when the load is applied in the ultra-microhardness test specified in JIS Z2255 (2003).

7. The image forming apparatus according to claim 6, wherein the surface layer has an average value of 40% or less of the ratio B / A × 100 (%).

8. The aforementioned R １ The image forming apparatus according to claim 1, wherein at least one of the groups is a methyl group or a phenyl group.

9. The aforementioned R １ The image forming apparatus according to claim 8, wherein at least one of the groups is a methyl group.

10. A charging step in which the surface of the image holder is charged, A step of forming an electrostatic image on the surface of the charged image holder, A developing step of developing an electrostatic image formed on the surface of an image holder as a toner image using an electrostatic image developer containing toner, wherein the toner particles contain a metallic pigment having an average equivalent circular diameter of 5 μm or more and 15 μm or less, the average value of the ratio b / a of the major axis diameter a to the minor axis diameter b in the cross-section of the toner particles is 0.5 or more and 0.8 or less, and the average value of the area of ​​the metallic pigment in the projected image of the toner particles when viewed from the thickness direction is 0.5 or more and 0.7 or less. A transfer step of transferring the toner image formed on the surface of the image holder to the surface of the recording medium, A fixing step in which a toner image is fixed to a recording medium by bringing the surface layer of a fixing member into contact with the toner image on the recording medium and applying heat and pressure, the fixing member having a surface layer having a surface layer having a surface layer where the difference ΔH between the maximum and minimum values ​​of ultramicrohardness measured at 50 arbitrary points according to the ultramicrohardness test specified in JIS Z2255 (2003) is 0 or more and 15 or less, and the surface layer of the fixing member having a surface layer having a surface layer having a surface layer where the difference ΔH between the maximum and minimum values ​​of ultramicrohardness is 0 or more and 15 or less, the surface layer of the fixing member having a surface layer has been brought into contact with the toner image on the recording medium and the toner image is fixed to the recording medium, An image forming method having the following characteristics. Formula 1 [R] １ SiO ３／２ ] ｍ (In Equation 1, R １ Each of these independently consists of a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an aryl group, and -C(=O)-CR ２ 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, a methyl group, or an ethyl group. ２ If there are multiple R ２ 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. (m represents a positive integer.)

Images