Toner for electrostatic charge image development, electrostatic charge image developer, toner cartridge, process cartridge, and image forming apparatus

Abstract

To provide an electrostatic image development toner capable of suppressing gloss difference that may arise when forming images continuously.SOLUTION: An electrostatic image development toner provided herein comprises toner parties containing a binder resin containing an amorphous resin and crystalline resin; a dye; and a mold release agent. A proportion of the crystalline resin on a surface of each toner particle is 15% or less as measured by X-ray photoelectron spectroscopy.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a toner for electrostatic charge image development, an electrostatic charge image developer, a toner cartridge, a process cartridge, and an image forming apparatus.

Background Art

[0002] Patent Document 1 proposes "an electrophotographic toner characterized by having a core layer containing at least a crystalline resin and a colorant, a wax layer containing a release agent covering the core layer, and a shell layer containing an amorphous resin covering the wax layer".

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In an electrostatic charge image developing toner containing toner particles including a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, when the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 15%, when the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 20% with respect to the ratio of the amorphous resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy, when the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 200% with respect to the ratio of the release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy, when the heat absorption amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g) and the heat absorption amount based on the endothermic peak derived from the crystalline resin in the second heating process is Qc2 (J / g), when 10 > Qc1 / Qc2, or in differential scanning calorimetry, when the heat absorption amount based on the endothermic peak derived from the crystalline resin in the first heating process is Qc1 (J / g) and the heat absorption amount Qw1 (J / g) based on the endothermic peak derived from the release agent in the first heating process, when 0.2 > Qc1 / Qw1, it is to provide an electrostatic charge image developing toner capable of suppressing the gloss difference generated when forming images continuously as compared with the case.

Means for Solving the Problems

[0005] The above problems are solved by the following means. That is <1> Having toner particles including a binder resin containing an amorphous resin and a crystalline resin, a dye, and a release agent, An electrostatic charge image developing toner in which the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 15% or less. <2> The electrostatic charge image developing toner according to <1> above, in which the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 1% or more and 8% or less. <3> The electrostatic charge image developing toner according to <2> above, in which the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 3% or more and 5% or less. <4> The toner for electrostatic charge image development according to any one of <1> to <3>, wherein the dye is a basic dye. <5> The toner for electrostatic charge image development according to <4>, wherein the basic dye is at least one selected from a rhodamine-based dye containing a cationic group and an azo-based dye containing a cationic group. <6> The content of the mold release agent with respect to the toner particles is 5.0% by mass or more and 10.0% by mass or less, The toner for electrostatic charge image development according to any one of <1> to <5>, wherein the ratio of the mold release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 3% or more and 15% or less. <7> The toner for electrostatic charge image development according to any one of <1> to <6>, wherein the melting temperature Tm of the crystalline resin is 60°C or higher and 80°C or lower. <8> The toner for electrostatic charge image development according to any one of <1> to <7>, wherein the glass transition temperature Tg of the amorphous resin is 45°C or higher and 60°C or lower. <9> The toner for electrostatic charge image development according to any one of <1> to <8>, wherein the binder resin contains a urea-modified polyester resin as the amorphous resin. <10> The toner for electrostatic charge image development according to any one of <1> to <9>, wherein the content of the crystalline resin with respect to the toner particles is 1% by mass or more and 12% by mass or less. <11> The toner for electrostatic charge image development according to any one of <1> to <10>, wherein the content of the dye with respect to the content of the crystalline resin is 5% by mass or more and 40% by mass or less. <12> Having toner particles containing a binder resin containing a non-binding resin and a crystalline resin, a dye, and a mold release agent, The ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 20% or less with respect to the ratio of the amorphous resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy, The toner for electrostatic charge image development, wherein the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 200% or less with respect to the ratio of the mold release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy. <13> It has toner particles containing a binder resin containing a non-crystalline resin and a crystalline resin, a dye, and a release agent, When the endothermic amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g), and the endothermic amount based on the endothermic peak derived from the crystalline resin in the second heating process is Qc2 (J / g), an electrostatic charge image developing toner satisfying the formula: 10 ≦ Qc1 / Qc2. <14> It has toner particles containing a binder resin containing a non-crystalline resin and a crystalline resin, a dye, and a release agent, When the endothermic amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g), and the endothermic amount Qw1 (J / g) based on the endothermic peak derived from the release agent in the first heating process, an electrostatic charge image developing toner satisfying the formula: 0.2 ≦ Qc1 / Qw1. <15> An electrostatic charge image developer containing the electrostatic charge image developing toner according to any one of <1> to <14> above. <16> It contains the electrostatic charge image developing toner according to any one of <1> to <14> above, A toner cartridge that is detachable from an image forming apparatus. <17> It contains the electrostatic charge image developer according to <15> above, and includes developing means for developing an electrostatic charge image formed on the surface of an image carrier as a toner image with the electrostatic charge image developer, A process cartridge that is detachable from an image forming apparatus. <18> An image carrier, Charging means for charging the surface of the image carrier, Electrostatic charge image forming means for forming an electrostatic charge image on the charged surface of the image carrier, <15> It contains the electrostatic charge image developer according to <15> above, and includes developing means for developing an electrostatic charge image formed on the surface of the image carrier as a toner image with the electrostatic charge image developer, Transfer means for transferring the toner image formed on the surface of the image carrier to the surface of a recording medium, Fixing means for fixing the toner image transferred to the surface of the recording medium, An image forming apparatus comprising the above. <19> The fixing means includes a fixing member and a pressing member that presses the outer peripheral surface of the fixing member and sandwiches a recording medium on which an unfixed toner image is formed on the surface together with the fixing member. The image forming apparatus according to <18>, which does not have a coating mechanism for applying a release agent to the surface of the fixing member.

Advantages of the Invention

[0006] According to the invention according to <1>, in an electrostatic charge image developing toner containing toner particles including a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, compared with the case where the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 15%, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming images is provided.

[0007] According to the invention according to <2>, in an electrostatic charge image developing toner containing toner particles including a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, compared with the case where the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 8%, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming images is provided.

[0008] According to the invention according to <3>, in an electrostatic charge image developing toner containing toner particles including a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, compared with the case where the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 5%, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming images is provided.

[0009] According to the invention according to <4>, in an electrostatic charge image developing toner containing toner particles containing a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, compared with the case where the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 15%, even if the dye is a basic dye, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when forming an image continuously is provided. According to the invention according to <5>, in an electrostatic charge image developing toner containing toner particles containing a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, compared with the case where the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 15%, even if the basic dye is at least one selected from a rhodamine-based dye containing a cationic group and an azo-based dye containing a cationic group, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when forming an image continuously is provided.

[0010] According to the invention according to <6>, compared with the case where the content of the release agent with respect to the toner particles is less than 5.0% by mass or exceeds 10.0% by mass, or the ratio of the release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy is less than 3% or exceeds 15%, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when forming an image continuously is provided.

[0011] According to the invention according to <7>, in an electrostatic charge image developing toner containing toner particles containing a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, compared with the case where the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 15%, even if the melting temperature Tm of the crystalline resin is 60°C or higher and 80°C or lower, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when forming an image continuously is provided. According to the invention according to <8>, in an electrostatic charge image developing toner containing toner particles including a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, compared with the case where the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 15%, even when the glass transition temperature Tg of the amorphous resin is 45°C or higher and 60°C or lower, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming an image is provided.

[0012] According to the invention according to <9>, in an electrostatic charge image developing toner containing toner particles including a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, compared with the case where the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 15%, the urea-modified polyester resin is included as the amorphous resin, and an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming an image is provided. According to the invention according to <10>, compared with the case where the content of the crystalline resin with respect to the toner particles is less than 1% by mass or exceeds 12% by mass, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming an image is provided. According to the invention according to <11>, compared with the case where the content of the dye with respect to the content of the crystalline resin is less than 5% by mass or exceeds 40% by mass, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming an image is provided.

[0013] According to the invention according to <12>, in an electrostatic charge image developing toner containing toner particles including a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, when the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 20% with respect to the ratio of the amorphous resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy, or when the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 200% with respect to the ratio of the release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming images is provided. According to the invention according to <13>, in an electrostatic charge image developing toner containing toner particles including a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, when the heat absorption amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g) and the heat absorption amount based on the endothermic peak derived from the crystalline resin in the second heating process is Qc2 (J / g), an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming images is provided as compared with the case where 10 > Qc1 / Qc2. According to the invention according to <14>, in an electrostatic charge image developing toner containing toner particles including a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, when the endothermic amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g), and the endothermic amount Qw1 (J / g) based on the endothermic peak derived from the release agent in the first heating process, an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming images is provided as compared with the case where 0.2 > Qc1 / Qw1. According to the inventions according to <15> to <19>, in an electrostatic charge image developing toner containing toner particles including a binder resin containing a crystalline resin and an amorphous resin, a dye, and a release agent, when the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 15%, when the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 20% with respect to the ratio of the amorphous resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy, when the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 200% with respect to the ratio of the release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy, when the endothermic amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g), and the endothermic amount based on the endothermic peak derived from the crystalline resin in the second heating process is Qc2 (J / g), when 10 > Qc1 / Qc2, or when the endothermic amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g), and the endothermic amount Qw1 (J / g) based on the endothermic peak derived from the release agent in the first heating process, an electrostatic charge image developing agent, a toner cartridge, a process cartridge, and an image forming apparatus including an electrostatic charge image developing toner capable of suppressing the gloss difference generated when continuously forming images are provided as compared with the case where 0.2 > Qc1 / Qw1.

Brief Description of Drawings

[0014]

Figure 1

Figure 2

Mode for Carrying Out the Invention

[0015] Hereinafter, embodiments which are examples of the present invention will be described. These descriptions and examples are illustrative of the embodiments and do not limit the scope of the invention. In the numerical ranges described step by step in this specification, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of the numerical range described in other step-by-step descriptions. Further, in the numerical ranges described in this specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.

[0016] Each component may contain a plurality of corresponding substances. When referring to the amount of each component in the composition, when there are a plurality of substances corresponding to each component in the composition, unless otherwise specified, it means the total amount of the plurality of substances present in the composition.

[0017] <Toner for electrostatic charge image development> The toner for electrostatic charge image development according to the first embodiment (hereinafter, the “toner for electrostatic charge image development” is also simply referred to as “toner”) has toner particles containing a binder resin containing an amorphous resin and a crystalline resin, a dye, and a release agent. And the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 15% or less.

[0018] The toner according to the first embodiment suppresses the gloss difference that occurs when forming images continuously with the above configuration. The reason is presumed as follows.

[0019] In recent years, the demand for toners with excellent low-temperature fixability has been increasing. In order to improve the low-temperature fixability of the toner, when the glass transition temperature of the binder resin is lowered, toner aggregation may easily occur during storage. Therefore, in order to achieve both improved low-temperature fixability and suppression of toner aggregation, a toner having toner particles containing an amorphous resin and a crystalline resin, and a release agent may be used. However, when the dispersion state of the amorphous resin and the crystalline resin in the toner particles is insufficient, this toner may cause poor fixing when the toner is fixed onto a recording medium, and the toner may easily adhere to the fixing member side. The toner adhering to the fixing member is removed by the cleaning member, but the release agent contained in the toner is difficult to remove and tends to remain on the fixing member. Therefore, during fixing when an image is formed again, in the portion of the fixing member where the release agent remains, the toner hardly adheres to the fixing member side, so a smooth-surfaced image can be obtained. However, in the portion of the fixing member where the release agent does not remain, the toner easily adheres to the fixing member side, so poor fixing is likely to occur and a phenomenon (i.e., offset) where a part of the image migrates to the fixing member is likely to occur. Thus, the obtained image may easily have a gloss difference. Here, the gloss difference refers to the difference in the gloss of the image.

[0020] And the above phenomenon when using a toner containing an amorphous resin and a crystalline resin as the binder resin may become prominent when using a toner having toner particles containing a binder resin containing an amorphous resin and a crystalline resin, a dye, and a release agent. The dye may have low affinity for the crystalline resin, and the crystalline resin is likely to be present in excess on the surface of the toner particles (for example, the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy exceeds 15%). This is presumably because while the dye tends to have low affinity for the crystalline resin, it tends to have high affinity for the amorphous resin, and the dye tends to be present on the inner side of the toner particles. Therefore, this toner is more likely to cause poor fixing and the toner is more likely to adhere to the fixing member side. Therefore, when continuously forming images, the gloss difference of the images is more likely to occur.

[0021] The toner according to the first embodiment has a proportion of the crystalline resin on the surface of the toner particles, measured by X-ray photoelectron spectroscopy, of 15% or less. Therefore, the amount of the crystalline resin present on the surface of the toner particles is reduced. As a result, this toner is less likely to cause poor fixing and tends to be less likely to adhere to the fixing member side. Therefore, even in the toner having toner particles containing a binder resin containing an amorphous resin and a crystalline resin, a dye, and a release agent, when forming images continuously, the gloss difference of the images is suppressed.

[0022] From the above, it is presumed that the toner according to the first embodiment suppresses the gloss difference that occurs when forming images continuously.

[0023] The toner according to the second embodiment has toner particles containing a binder resin containing a non-crystalline resin and a crystalline resin, a dye, and a release agent. And the proportion of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 20% or less with respect to the proportion of the amorphous resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy, and the proportion of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 200% or less with respect to the proportion of the release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy.

[0024] The toner according to the second embodiment suppresses the gloss difference that occurs when forming images continuously with the above configuration. The reason is presumed as follows.

[0025] The toner according to the second embodiment has the proportion of the crystalline resin on the toner particle surface measured by X-ray photoelectron spectroscopy to be 20% or less with respect to the proportion of the amorphous resin on the toner particle surface measured by X-ray photoelectron spectroscopy. Therefore, the amount of the crystalline resin present on the toner particle surface is reduced. Also, the proportion of the crystalline resin on the toner particle surface measured by X-ray photoelectron spectroscopy is set to 200% or less with respect to the proportion of the release agent on the toner particle surface measured by X-ray photoelectron spectroscopy. As a result, the release agent is appropriately present on the toner particle surface. Thus, the toner according to this embodiment can appropriately supply the release agent to the fixing member during fixing. From the above, the toner is less likely to cause poor fixing and has a tendency that toner is less likely to adhere to the fixing member side. Therefore, even in a toner having toner particles containing a binder resin containing an amorphous resin and a crystalline resin, a dye, and a release agent, when continuously forming an image, the gloss difference of the image is suppressed.

[0026] From the above, it is presumed that the toner according to the second embodiment suppresses the gloss difference that occurs when continuously forming an image.

[0027] The toner according to the third embodiment has toner particles containing a binder resin containing a non-crystalline resin and a crystalline resin, a dye, and a release agent. And when the endothermic amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g) and the endothermic amount based on the endothermic peak derived from the crystalline resin in the second heating process is Qc2 (J / g), the formula: 10 ≤ Qc1 / Qc2 is satisfied.

[0028] The toner according to the third embodiment suppresses the gloss difference that occurs when continuously forming an image with the above configuration. The reason is presumed as follows.

[0029] Here, the endothermic amount based on the endothermic peak derived from the crystalline resin in the heating process in the differential scanning calorimetry of the toner particles is the endothermic amount based on the endothermic peak of the crystalline resin phase-separated from the amorphous resin. And the endothermic quantity Qc1 (J / g) based on the endothermic peak derived from the crystalline resin in the first heating process represents the measurement result in a state where the compatible amount (compatible part) of the crystalline resin with respect to the amorphous resin is small. The endothermic quantity Qc2 (J / g) based on the endothermic peak derived from the crystalline resin in the second heating process represents the measurement result in a state where the compatible amount (compatible part) of the crystalline resin with respect to the amorphous resin is large. That is, if the value (Qc1 / Qc2) of the endothermic quantity Qc1 with respect to the endothermic quantity Qc2 is high, it means that the compatible amount (compatible part) of the crystalline resin with respect to the amorphous resin is small and the phase separation amount of the crystalline resin is large. On the other hand, if the value (Qc1 / Qc2) of the endothermic quantity Qc1 with respect to the endothermic quantity Qc2 is low, it means that the compatible amount (compatible part) of the crystalline resin with respect to the amorphous resin is large and the phase separation amount of the crystalline resin is small. The toner according to the third embodiment satisfies the formula: 10 ≦ Qc1 / Qc2. Therefore, the toner according to the third embodiment tends to have a small compatible amount (compatible part) of the crystalline resin with respect to the amorphous resin and a large phase separation amount of the crystalline resin. Also, by satisfying the above formula, since the proportion of the phase-separated crystalline resin existing in the form of domains inside the toner particles tends to be large, the amount of the crystalline resin present on the surface of the toner particles is reduced. Therefore, this toner is less likely to cause poor fixing and is less likely to adhere to the fixing member side. Therefore, the toner according to the third embodiment can also suppress the gloss difference of the image when continuously forming images even in a toner having toner particles containing a binder resin containing an amorphous resin and a crystalline resin, a dye, and a release agent.

[0030] From the above, it is presumed that the toner according to the third embodiment suppresses the gloss difference that occurs when continuously forming images.

[0031] The toner according to the fourth embodiment has toner particles containing a binder resin containing a non-binding resin and a crystalline resin, a dye, and a release agent. Furthermore, when the heat absorption amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g), and the heat absorption amount Qw1 (J / g) based on the endothermic peak derived from the mold release agent in the first heating process, the formula: 0.2 ≦ Qc1 / Qw1 is satisfied. Here, in the differential scanning calorimetry of the toner particles, the heat absorption amount based on the endothermic peak derived from the mold release agent in the heating process is the heat absorption amount based on the endothermic peak derived from the mold release agent phase-separated from the binder resin. The toner according to the fourth embodiment satisfies the formula: 0.2 ≦ Qc1 / Qw1, so that the value of Qc1 tends to be a relatively high value and the value of Qw1 tends to be a relatively low value. Then, the compatible amount (compatible part) of the crystalline resin with respect to the amorphous resin is small, and the compatible part of the mold release agent with respect to the binder resin is large. Such a toner is likely to have the mold release agent oozing out during fixing, and the mold release agent can be appropriately supplied to the fixing member. From the above, the toner is less likely to cause fixing failure and is less likely to adhere to the fixing member side. Therefore, the toner according to the fourth embodiment also suppresses the gloss difference of the image when continuously forming images even in a toner having toner particles containing a binder resin containing an amorphous resin and a crystalline resin, a dye, and a mold release agent.

[0032] Hereinafter, a toner (hereinafter also referred to as "the toner according to the present embodiment") applicable to any of the toners according to the first to fourth embodiments will be described in detail. However, an example of the toner of the present invention may be any toner corresponding to any one of the toners according to the first to fourth embodiments.

[0033] (Toner particles) The toner particles contain a binder resin containing an amorphous resin and a crystalline resin, a dye, and a mold release agent.

[0034] -Binder resin- Examples of the binder resin include homopolymers 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.), olefins (e.g., ethylene, propylene, butadiene, etc.), or copolymers obtained by combining two or more of these monomers, i.e., vinyl resins. Examples of the binder resin also include non-vinyl resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, modified rosin, mixtures of these and the above vinyl resins, or graft polymers obtained by polymerizing vinyl monomers in the presence of these. These binder resins may be used alone or in combination of two or more.

[0035] The binder resin contains an amorphous resin and a crystalline resin. Here, the amorphous resin refers to a resin that has only a stepwise endothermic change but no distinct endothermic peak in thermal analysis measurement using differential scanning calorimetry (DSC), is a solid at room temperature, and is thermoplastified at a temperature above the glass transition temperature. On the other hand, the crystalline resin refers to a resin that has a distinct endothermic peak rather than a stepwise change in the endothermic amount in differential scanning calorimetry (DSC). Specifically, for example, the crystalline resin means that the half-width of the endothermic peak measured at a heating rate of 10 °C / min is within 10 °C, and the amorphous resin means a resin with a half-width exceeding 10 °C or a resin for which no distinct endothermic peak is observed.

[0036] An amorphous resin will be described. Examples of the amorphous resin include known amorphous resins such as amorphous polyester resins, amorphous vinyl resins (e.g., styrene-acrylic resins, etc.), epoxy resins, polycarbonate resins, and polyurethane resins. Among these, amorphous polyester resins and amorphous vinyl resins (especially styrene-acrylic resins) are preferred, and amorphous polyester resins are more preferred.

[0037] · Amorphous polyester resin Examples of the amorphous polyester resin include polycondensates of polyvalent carboxylic acids and polyhydric alcohols. Note that as the amorphous polyester resin, commercially available products may be used, or those synthesized may be used.

[0038] Examples of the polyvalent carboxylic acid include aliphatic dicarboxylic acids (e.g., oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, alkenyl succinic acid, adipic acid, sebacic acid, etc.), alicyclic dicarboxylic acids (e.g., cyclohexanedicarboxylic acid, etc.), aromatic dicarboxylic acids (e.g., terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, etc.), anhydrides thereof, or lower (e.g., having 1 to 5 carbon atoms) alkyl esters thereof. Among these, as the polyvalent carboxylic acid, for example, aromatic dicarboxylic acids are preferred. The polyvalent carboxylic acid may be used in combination with a trivalent or higher carboxylic acid having a crosslinked structure or a branched structure together with the dicarboxylic acid. Examples of the trivalent or higher carboxylic acid include trimellitic acid, pyromellitic acid, anhydrides thereof, or lower (e.g., having 1 to 5 carbon atoms) alkyl esters thereof. The polyvalent carboxylic acid may be used alone or in combination of two or more.

[0039] Examples of the polyhydric alcohol include aliphatic diols (such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, etc.), alicyclic diols (such as cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, etc.), and aromatic diols (such as ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, etc.). Among these, as the polyhydric alcohol, for example, aromatic diols and alicyclic diols are preferable, and aromatic diols are more preferable. As the polyhydric alcohol, a polyhydric alcohol having a crosslinked structure or a branched structure with a valence of 3 or more may be used in combination with the diol. Examples of the polyhydric alcohol having a valence of 3 or more include glycerin, trimethylolpropane, and pentaerythritol. The polyhydric alcohol may be used alone or in combination of two or more.

[0040] The amorphous polyester resin can be obtained by a well-known production method. Specifically, for example, it can be obtained by a method in which the polymerization temperature is set to 180°C or higher and 230°C or lower, the inside of the reaction system is depressurized as necessary, and the reaction is carried out while removing water or alcohol generated during condensation. When the raw material monomer is not dissolved or compatible at the reaction temperature, a high-boiling solvent may be added as a dissolution aid to dissolve it. In this case, the polycondensation reaction is carried out while distilling off the dissolution aid. When there is a monomer with poor compatibility, it is advisable to condense the monomer with poor compatibility in advance with an acid or alcohol to be polycondensed with the monomer, and then carry out polycondensation together with the main component.

[0041] Here, the amorphous polyester resin includes, in addition to the above-described unmodified amorphous polyester resin, a modified amorphous polyester resin. The modified amorphous polyester resin is an amorphous polyester resin in which a bonding group other than an ester bond is present, or an amorphous polyester resin in which a resin component different from the amorphous polyester resin component is bonded by a covalent bond, an ionic bond, or the like. Examples of the modified amorphous polyester resin include an amorphous polyester resin having a functional group such as an isocyanate group that reacts with an acid group or a hydroxyl group at the terminal, and a resin obtained by reacting with an active hydrogen compound to modify the terminal.

[0042] As the modified amorphous polyester resin, a urea-modified amorphous polyester resin (hereinafter, also simply referred to as "urea-modified polyester resin") is preferable.

[0043] When the binder resin contains a urea-modified polyester resin as the amorphous polyester resin, an effect of improving peelability by controlling the molecular weight distribution and viscoelasticity can be obtained, so that the gloss difference generated when forming an image continuously can be more suppressed.

[0044] The urea-modified polyester resin is preferably a urea-modified polyester resin obtained by a reaction (at least one of a crosslinking reaction and an elongation reaction) between an amorphous polyester resin having an isocyanate group (amorphous polyester prepolymer) and an amine compound. Note that the urea-modified polyester resin may contain a urethane bond together with a urea bond.

[0045] Examples of the amorphous polyester prepolymer having an isocyanate group include an amorphous polyester resin which is a polycondensate of a polyvalent carboxylic acid and a polyhydric alcohol, and an amorphous polyester prepolymer obtained by reacting a polyvalent isocyanate compound with an amorphous polyester resin having an active hydrogen. Examples of the group having an active hydrogen in the amorphous polyester resin include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, etc., and an alcoholic hydroxyl group is preferable.

[0046] In the amorphous polyester prepolymer having an isocyanate group, the polyvalent carboxylic acid and polyhydric alcohol are compounds similar to the polyvalent carboxylic acid and polyhydric alcohol described for the amorphous polyester resin.

[0047] Examples of the polyvalent isocyanate compound include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethyl caproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); aromatic diisocyanates (toluene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α,α,α’,α’-tetramethylxylylene diisocyanate, etc.); isocyanurates; and those obtained by blocking the above polyisocyanates with a blocking agent such as a phenol derivative, oxime, or caprolactam. The polyvalent isocyanate compound may be used alone or in combination of two or more.

[0048] The ratio of the polyvalent isocyanate compound is preferably 1 / 1 or more and 5 / 1 or less, more preferably 1.2 / 1 or more and 4 / 1 or less, and still more preferably 1.5 / 1 or more and 2.5 / 1 or less as the equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] to the hydroxyl group [OH] of the amorphous polyester prepolymer having a hydroxyl group.

[0049] In the amorphous polyester prepolymer having an isocyanate group, the content of the component derived from the polyvalent isocyanate compound is preferably 0.5% by mass or more and 40% by mass or less, more preferably 1% by mass or more and 30% by mass or less, and still more preferably 2% by mass or more and 20% by mass or less based on the whole amorphous polyester prepolymer having an isocyanate group.

[0050] The number of isocyanate groups contained per molecule of the amorphous polyester prepolymer having isocyanate groups is preferably at least 1 on average, more preferably at least 1.5 and at most 3 on average, and still more preferably at least 1.8 and at most 2.5 on average.

[0051] Examples of the amine compound that reacts with the amorphous polyester prepolymer having isocyanate groups include diamines, polyamines having a valence of 3 or more, amino alcohols, amino mercaptans, amino acids, and compounds in which these amino groups are blocked.

[0052] Examples of diamines include aromatic diamines (such as phenylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenylmethane); alicyclic diamines (such as 4,4'-diamino-3,3'-dimethyldicyclohexylmethane, diamine cyclohexane, isophoronediamine); and aliphatic diamines (such as ethylenediamine, tetramethylenediamine, hexamethylenediamine). Examples of polyamines having a valence of 3 or more include diethylenetriamine, triethylenetetramine, and the like. Examples of amino alcohols include ethanolamine, hydroxyethylaniline, and the like. Examples of amino mercaptans include aminoethyl mercaptan, aminopropyl mercaptan, and the like. Examples of amino acids include aminopropionic acid, aminocaproic acid, and the like. Examples of those in which these amino groups are blocked include ketimine compounds, oxazoline compounds, etc. obtained from amine compounds such as diamines, polyamines having a valence of 3 or more, amino alcohols, amino mercaptans, amino acids, and ketone compounds (such as acetone, methyl ethyl ketone, methyl isobutyl ketone). Among these amine compounds, ketimine compounds are preferred. The amine compound may be used alone or in combination of two or more.

[0053] Incidentally, the urea-modified polyester resin may be a resin in which the reaction (at least one of the crosslinking reaction and the elongation reaction) between the amorphous polyester resin (amorphous polyester prepolymer) having an isocyanate group and the amine compound is adjusted by a stopper (hereinafter also referred to as "crosslinking / elongation reaction stopper") that stops at least one of the crosslinking reaction and the elongation reaction, and the molecular weight after the reaction is adjusted. Examples of the crosslinking / elongation reaction stopper include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.) and those blocked thereof (ketimine compounds).

[0054] The ratio of the amine compound is preferably 1 / 2 or more and 2 / 1 or less, more preferably 1 / 1.5 or more and 1.5 / 1 or less, and still more preferably 1 / 1.2 or more and 1.2 / 1 or less, as the equivalent ratio [NCO] / [NHx] of the isocyanate group [NCO] in the amorphous polyester prepolymer having an isocyanate group and the amino group [NHx] in the amines.

[0055] The characteristics of the amorphous resin will be described. The glass transition temperature (Tg) of the amorphous resin may be 45°C or higher and 60°C or lower, may be 48°C or higher and 65°C or lower, or may be 50°C or higher and 60°C or lower.

[0056] When the glass transition temperature Tg of the amorphous resin is within the above range, toner adhesion to the fixing member during fixing is more likely to occur. However, the toner according to the present embodiment can suppress the gloss difference that occurs when forming an image continuously by adjusting the content of the crystalline resin on the surface of the toner particles even when the glass transition temperature Tg of the amorphous resin is within the above range.

[0057] Incidentally, the glass transition temperature is determined from the DSC curve obtained by differential scanning calorimetry (DSC), and more specifically, it is determined by the "extrapolated glass transition start temperature" described in the method for determining the glass transition temperature of JIS K 7121-1987 "Method for Measuring the Transition Temperature of Plastics".

[0058] The weight average molecular weight (Mw) of the amorphous resin is preferably 5,000 or more and 1,000,000 or less, more preferably 7,000 or more and 500,000 or less. The number average molecular weight (Mn) of the amorphous resin is preferably 2,000 or more and 100,000 or less. The molecular weight distribution Mw / Mn of the amorphous resin is preferably 1.5 or more and 100 or less, more preferably 2 or more and 60 or less. The weight average molecular weight and the number average molecular weight are measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC is performed using Tosoh's GPC·HLC-8120GPC as the measurement device, Tosoh's column·TSKgel SuperHM-M (15 cm), and a THF solvent. The weight average molecular weight and the number average molecular weight are calculated using the molecular weight calibration curve prepared from the measurement results with a monodisperse polystyrene standard sample.

[0059] The crystalline resin will be described. Examples of the crystalline resin include known crystalline resins such as crystalline polyester resins and crystalline vinyl resins (for example, polyalkylene resins, long-chain alkyl (meth)acrylate resins, etc.). Among these, crystalline polyester resins are preferred from the viewpoints of the mechanical strength and low-temperature fixability of the toner.

[0060] · Crystalline polyester resin The crystalline polyester resin includes, for example, polycondensates of polyvalent carboxylic acids and polyhydric alcohols. Note that as the crystalline polyester resin, commercially available products may be used, or those synthesized may be used. Here, since the crystalline polyester resin easily forms a crystal structure, a polycondensate using a polymerizable monomer having a linear aliphatic group rather than a polymerizable monomer having an aromatic group is preferred.

[0061] Examples of the polyvalent carboxylic acid include aliphatic dicarboxylic acids (such as 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 (such as dibasic acids such as phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, etc.), anhydrides thereof, or lower (e.g., having 1 to 5 carbon atoms) alkyl esters thereof. As the polyvalent carboxylic acid, a carboxylic acid having a trivalent or higher valence that forms a crosslinked structure or a branched structure may be used in combination with the dicarboxylic acid. Examples of the trivalent carboxylic acid include aromatic carboxylic acids (such as 1,2,3-benzenetricarboxylic acid, 1,2,4-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, etc.), anhydrides thereof, or lower (e.g., having 1 to 5 carbon atoms) alkyl esters thereof. As the polyvalent carboxylic acid, a dicarboxylic acid having a sulfonic acid group or a dicarboxylic acid having an ethylenic double bond may be used in combination with these dicarboxylic acids. The polyvalent carboxylic acid may be used alone or in combination of two or more.

[0062] Examples of the polyhydric alcohol include aliphatic diols (such as linear aliphatic diols having 7 to 20 carbon atoms in the main chain portion). Examples of the aliphatic diol 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, 1,14-eicosanedecanediol, etc. Among these, as the aliphatic diol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferable. The polyhydric alcohol may be used in combination with a polyhydric alcohol having a trivalent or higher valence that forms a crosslinked structure or a branched structure together with the diol. Examples of the polyhydric alcohol having a trivalent or higher valence include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, and the like. The polyhydric alcohol may be used alone or in combination of two or more.

[0063] Here, the polyhydric alcohol preferably has an aliphatic diol content of 80 mol% or more, and preferably 90 mol% or more.

[0064] The melting temperature of the crystalline polyester resin may be 60°C or higher and 80°C or lower, may be 62°C or higher and 75°C or lower, or may be 65°C or higher and 70°C or lower. The melting temperature is determined from the DSC curve obtained by differential scanning calorimetry (DSC) according to the "melting peak temperature" described in the method for determining the melting temperature in JIS K7121-1987 "Method for Measuring the Transition Temperature of Plastics".

[0065] The weight average molecular weight (Mw) of the crystalline polyester resin is preferably 6,000 or more and 35,000 or less.

[0066] The crystalline polyester resin can be obtained by a well-known production method, for example, in the same manner as the amorphous polyester.

[0067] The characteristics of the crystalline resin will be described. The melting temperature Tm of the crystalline resin may be 60°C or higher and 80°C or lower, may be 62°C or higher and 75°C or lower, or may be 65°C or higher and 70°C or lower. When the melting temperature Tm of the crystalline resin is within the above range, toner adhesion to the fixing member during fixing is more likely to occur. However, the toner according to the present embodiment can suppress the gloss difference that occurs when forming an image continuously by adjusting the content of the crystalline resin on the surface of the toner particles even when the melting temperature Tm of the crystalline resin is within the above range.

[0068] The melting temperature is determined by the "melting peak temperature" described in the method for determining the melting temperature of JIS K7121-1987 "Method for Measuring Transition Temperature of Plastics" from the DSC curve obtained by differential scanning calorimetry (DSC).

[0069] The weight average molecular weight (Mw) of the crystalline resin is preferably 6,000 or more and 35,000 or less.

[0070] As the content of the binder resin, for example, it is preferably 40% by mass or more and 95% by mass or less, more preferably 50% by mass or more and 90% by mass or less, and even more preferably 60% by mass or more and 85% by mass or less with respect to the entire toner particles.

[0071] The content of the crystalline resin with respect to the toner particles is preferably 1% by mass or more and 12% by mass or less, more preferably 3% by mass or more and 10% by mass or less, and even more preferably 5% by mass or more and 8% by mass or less. By setting the content of the crystalline resin within the above range, it is possible to suppress poor melting in the low temperature range and insufficient viscoelasticity in the high temperature range, and it becomes possible to reduce image offset to the fixing member. Therefore, the gloss difference generated when forming images continuously is further suppressed.

[0072] - Dye - The toner particles contain a dye. Here, the "dye" is a colorant having a solubility of 0.1 g or more in 100 g of water at 23°C or a solubility of 0.1 g or more in 100 g of cyclohexanone at 23°C.

[0073] The dye is not particularly limited, and examples include basic dyes, acidic dyes, mordant dyes, acid mordant dyes, direct dyes, disperse dyes, sulfur dyes, vat dyes, azoic dyes, oxidation dyes, reactive dyes, oil-soluble dyes, food colorants, natural pigments, or fluorescent whitening agents. These dyes may be used alone or in combination of two or more.

[0074] From the viewpoint of color development, the dye is preferably a basic dye. Here, when the dye is a basic dye, it tends to have a lower affinity for the crystalline resin compared to other types of dyes. Therefore, the gloss difference that occurs when forming an image continuously tends to be larger. However, for the toner according to the present embodiment, the content of the crystalline resin on the toner particle surface is 15% or less. Therefore, the amount of the crystalline resin present on the toner particle surface is reduced, and even when the dye is a basic dye, the gloss difference that occurs when forming an image continuously is suppressed.

[0075] When the dye is at least one selected from a rhodamine-based dye containing a cationic group and an azo-based dye containing a cationic group among basic dyes, it particularly tends to have a lower affinity for the crystalline resin among basic dyes. Therefore, the gloss difference that occurs when forming an image continuously tends to be larger. However, for the toner according to the present embodiment, the content of the crystalline resin on the toner particle surface is 15% or less. Therefore, the amount of the crystalline resin present on the toner particle surface is reduced, and even when the dye is a basic dye, the gloss difference that occurs when forming an image continuously is suppressed.

[0076] Hereinafter, the basic dye will be specifically described. The basic dye refers to a dye having a cationic group. The cationic group is preferably an onium group, more preferably an ammonium group, an iminium group, or a pyridinium group, still more preferably an ammonium group, and particularly preferably a quaternary ammonium group. The basic dye may have only one cationic group or two or more cationic groups. However, from the viewpoint of fluorescence intensity, it preferably has one or more and four or less cationic groups, more preferably one or two cationic groups, and particularly preferably only one cationic group. Examples of basic dyes include, specifically, diazine dyes containing a cationic group, oxazine dyes containing a cationic group, thiazine dyes containing a cationic group, azo dyes containing a cationic group, anthraquinone dyes containing a cationic group, rhodamine dyes containing a cationic group, triarylmethane dyes containing a cationic group, phthalocyanine dyes containing a cationic group, auramine dyes containing a cationic group, acridine dyes containing a cationic group, methine dyes containing a cationic group, and the like. Specifically, the following dyes can be mentioned. For example, "Basic Red 2" etc. are also referred to as "C.I.Basic Red 2" etc.

[0077] A diazine dye containing a cationic group refers to a dye having a cationic group and a diazine skeleton within the same molecule. Specific examples of diazine dyes containing a cationic group include Basic Red 2, 5, 6, 10, Basic Blue 13, 14, 16, Basic Violet 5, 6, 8, 12, Basic Yellow 14, etc.

[0078] An oxazine dye containing a cationic group refers to a dye having a cationic group and an oxazine skeleton within the same molecule. Specific examples of oxazine dyes containing a cationic group include Basic Blue 3, 6, 10, 12, 74, etc.

[0079] A thiazine dye containing a cationic group refers to a dye having a cationic group and a thiazine skeleton within the same molecule. Specific examples of thiazine dyes containing a cationic group include Basic Blue 9, 17, 24, 25, Basic Green 5, etc.

[0080] An azo dye containing a cationic group refers to a dye having a cationic group and an azo group within the same molecule. Examples of azo dyes containing a cationic group specifically include Basic Red 18, 22, 23, 24, 29, 30, 31, 32, 34, 38, 39, 46, 51, 53, 54, 55, 62, 64, 76, 94, 111, 118, Basic Blue 41, 53, 54, 55, 64, 65, 66, 67, 162, Basic Violet 18, 36, Basic Yellow 15, 19, 24, 25, 28, 29, 38, 39, 49, 51, 57, 62, 73, Basic Orange 1, 2, 24, 25, 29, 30, 33, 54, 69, etc.

[0081] An anthraquinone dye containing a cationic group refers to a dye having a cationic group and an anthraquinone skeleton within the same molecule. Examples of anthraquinone dyes containing a cationic group specifically include Basic Blue 22, 44, 47, 72, etc.

[0082] A rhodamine dye containing a cationic group refers to a dye having a cationic group and a rhodamine skeleton within the same molecule. Here, the rhodamine skeleton refers to the structure shown in the following formula (1).

[0083]

Chemical formula

[0084] Examples of rhodamine dyes containing a cationic group specifically include Basic Red 1, 1:1, 3, 4, 8, 11, Basic Violet 10, 11, 11:1, etc.

[0085] A triarylmethane dye containing a cationic group refers to a dye having a cationic group and a triarylmethane skeleton within the same molecule. The triarylmethane skeleton refers to a structure having three aryl groups on the same carbon. Examples of triarylmethane dyes containing a cationic group include Basic Red 9, Basic Blue 1, 2, 5, 7, 8, 11, 15, 18, 20, 23, 26, 35, 81, Basic Violet 1, 2, 3, 4, 14, 23, Basic Green 1, 4, etc.

[0086] The phthalocyanine dyes containing a cationic group refer to dyes having a cationic group and a phthalocyanine skeleton within the same molecule. Examples of phthalocyanine dyes containing a cationic group include Basic Blue 140, etc.

[0087] The auramine dyes containing a cationic group refer to dyes having a cationic group and an auramine skeleton within the same molecule. Examples of auramine dyes containing a cationic group include Basic Yellow 2, 3, 37, etc.

[0088] The acridine dyes containing a cationic group refer to dyes having a cationic group and an acridine skeleton within the same molecule. Examples of acridine dyes containing a cationic group include Basic Yellow 5, 6, 7, 9, Basic Orange 4, 5, 14, 15, 16, 17, 18, 19, 23, etc.

[0089] The methine dyes containing a cationic group refer to dyes having a cationic group and an indole skeleton within the same molecule. Examples of methine dyes containing a cationic group include Basic Red 12, 13, 14, 15, 27, 28, 37, 52, 90, Basic Yellow 11, 13, 20, 21, 52, 53, Basic Orange 21, 22, Basic Violet 7, 15, 16, 20, 21, 22, etc.

[0090] The content of the dye with respect to the content of the crystalline resin is preferably 5% by mass or more and 40% by mass or less, more preferably 8% by mass or more and 30% by mass or less, and still more preferably 10% by mass or more and 20% by mass or less.

[0091] By setting the content of the dye within the above range, the gloss difference generated when forming an image continuously is more suppressed. The reason is presumed as follows. When the content of the dye with respect to the content of the crystalline resin is 5% by mass or more, the compatibilization of the amorphous resin and the crystalline resin is suppressed, improving the fixing property in the low temperature range. When the content of the dye with respect to the content of the crystalline resin is 40% by mass or less, the viscoelasticity is improved by the filler effect, and the peelability in the high temperature range becomes good. Therefore, the gloss difference generated when forming an image continuously is more suppressed.

[0092] -Release agent- Examples of the release agent include hydrocarbon waxes; natural waxes such as carnauba wax, rice wax, and candelilla wax; synthetic or mineral / oil-based waxes such as montan wax; ester waxes such as fatty acid esters and montanic acid esters; and the like. The release agent is not limited thereto.

[0093] The melting temperature of the release agent is preferably 50°C or more and 110°C or less, more preferably 60°C or more and 100°C or less. The melting temperature is determined by the "melting peak temperature" described in the method for obtaining the melting temperature in JIS K 7121-1987 "Method for Measuring the Transition Temperature of Plastics" from the DSC curve obtained by differential scanning calorimetry (DSC).

[0094] From the viewpoint of suppressing the gloss difference generated when forming an image continuously, the content of the release agent is preferably 1.0% by mass or more and 20.0% by mass or less, more preferably 5.0% by mass or more and 15.0% by mass or less, and still more preferably 5.0% by mass or more and 10.0% by mass or less with respect to the entire toner particles.

[0095] From the perspective of suppressing the gloss difference that occurs when forming images continuously, it is preferable that the ratio of the release agent on the surface of the toner particles, measured by X-ray photoelectron spectroscopy, is 20% or more and 50% or less, more preferably 25% or more and 45% or less, and particularly preferably 30% or more and 40% or less. Here, the measurement procedure for the content of the release agent on the surface of the toner particles will be described later.

[0096] In particular, it is preferable that the content of the release agent with respect to the toner particles is 5.0 mass% or more and 10.0 mass% or less, and the ratio of the release agent on the surface of the toner particles, measured by X-ray photoelectron spectroscopy, is 3% or more and 15% or less.

[0097] By setting the content of the release agent within the above range and appropriately presenting the release agent on the surface of the toner particles, the release agent is more likely to ooze out during toner fixing, the fixing failure of the toner is further suppressed, and the adhesion of the toner to the fixing member side is suppressed. Therefore, the gloss difference that occurs when forming images continuously is further suppressed.

[0098] -Other Additives- Examples of 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. Also, as the colorant, a pigment may be used in combination with a dye. Examples of pigments include various pigments such as carbon black, chrome yellow, Hansa yellow, benzidine yellow, threne yellow, quinoline yellow, pigment yellow, permanent orange GTR, pyrazolone orange, Balkan orange, Watchung red, permanent red, brilliant carmine 3B, brilliant carmine 6B, DuPont oil red, pyrazolone red, resorcin red, rhodamine B lake, lake red C, pigment red, rose bengal, aniline blue, ultramarine blue, calco oil blue, methylene blue chloride, phthalocyanine blue, pigment blue, phthalocyanine green, malachite green oxalate, and the like.

[0099] - Content of crystalline resin on the toner particle surface - The ratio of the crystalline resin on the toner particle surface measured by X-ray photoelectron spectroscopy is 15% or less.

[0100] Here, the measurement procedure for the content of the crystalline resin on the toner particle surface will be described later.

[0101] The ratio of the crystalline resin on the toner particle surface measured by X-ray photoelectron spectroscopy is preferably 1% or more and 8% or less, and more preferably 3% or more and 5% or less.

[0102] By setting the content of the crystalline resin on the toner particle surface within the above range, while maintaining low-temperature fixability, the amount of the crystalline resin present on the toner particle surface is further reduced. Therefore, when forming images continuously, the gloss difference of the images is more suppressed. Also, when fixing to a recording medium, if the mixing of the crystalline resin and the amorphous resin is insufficient, the image intensity may decrease. By setting the content of the crystalline resin on the toner particle surface within the above range, when fixing to a recording medium, the crystalline resin and the amorphous resin are more likely to be mixed. Therefore, the image intensity is improved.

[0103] - Composition ratio on the toner particle surface - The toner according to this embodiment has a proportion of crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy that is 20% or less with respect to the proportion of amorphous resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy. Also, the proportion of crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 200% or less with respect to the proportion of mold release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy.

[0104] From the viewpoint of suppressing the gloss difference that occurs when forming images continuously, the proportion of crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is preferably 1% or more and 20% or less, more preferably 2% or more and 12% or less, and still more preferably 3% or more and 8% or less with respect to the proportion of amorphous resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy.

[0105] From the viewpoint of suppressing the gloss difference that occurs when forming images continuously, the proportion of crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is preferably 5% or more and 200% or less, more preferably 10% or more and 80% or less, and still more preferably 20% or more and 40% or less with respect to the proportion of mold release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy.

[0106] -Method for measuring the content of each component on the surface of toner particles- The proportions of crystalline resin, amorphous resin, and mold release agent on the surface of the toner particles are determined by XPS (X-ray photoelectron spectroscopy) measurement. As the XPS measurement apparatus, JPS-9000MX manufactured by JEOL Ltd. is used, and in the measurement, MgKα rays are used as the X-ray source, the acceleration voltage is 10 kV, and the emission current is 30 mA. First, by focusing on the ratio of carbon atoms, the release agent, amorphous resin, and crystalline resin among the components contained in the toner particles of the toner to be measured are identified. Then, the release agent, amorphous resin, and crystalline resin contained in the toner particles of the toner to be measured are each individually subjected to XPS measurement to obtain a C1S spectrum. Subsequently, XPS measurement of the toner to be measured is performed to quantify the ratios of the crystalline resin, amorphous resin, and release agent on the surface of the toner particles. Here, the quantification of the ratios of the crystalline resin, amorphous resin, and release agent on the surface of the toner particles is performed by the peak separation method of the C1S spectrum. The peak separation method separates the measured C1S spectrum into each component using curve fitting by the least squares method. As the component spectra for the basis of separation, the C1S spectra obtained by individually measuring the release agent, amorphous resin, and crystalline resin contained in the toner particles of the toner to be measured are used. The ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is the ratio of the C1S spectrum intensity of the crystalline resin on the surface of the toner particles to the C1S spectrum intensity on the surface of the toner particles. The ratio of the amorphous resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is the ratio of the C1S spectrum intensity of the amorphous resin on the surface of the toner particles to the C1S spectrum intensity on the surface of the toner particles. The ratio of the release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy is the ratio of the C1S spectrum intensity of the release agent on the surface of the toner particles to the C1S spectrum intensity on the surface of the toner particles.

[0107] -Qc1 / Qc2- For the toner according to this embodiment, when the heat absorption amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g) and the heat absorption amount based on the endothermic peak derived from the crystalline resin in the second heating process is Qc2 (J / g), the formula: 10 ≦ Qc1 / Qc2 is satisfied.

[0108] From the perspective of suppressing the gloss difference that occurs when forming images continuously, it is preferable that Qc1 and Qc2 satisfy the formula: 10 ≦ Qc1 / Qc2 ≦ 30, more preferably satisfy the formula: 12 ≦ Qc1 / Qc2 ≦ 25, and even more preferably satisfy the formula: 15 ≦ Qc1 / Qc2 ≦ 20.

[0109] -Qc1 / Qw1- For the toner according to this embodiment, when the heat absorption amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g), and the heat absorption amount Qw1 (J / g) based on the endothermic peak derived from the release agent in the first heating process, it satisfies the formula: 0.2 ≦ Qc1 / Qw1.

[0110] From the perspective of suppressing the gloss difference that occurs when forming images continuously, it is preferable that Qc1 and Qw1 satisfy the formula: 0.2 ≦ Qc1 / Qw1 ≦ 0.6, more preferably satisfy the formula: 0.3 ≦ Qc1 / Qw1 ≦ 0.5, and even more preferably satisfy the formula: 0.35 ≦ Qc1 / Qw1 ≦ 0.45.

[0111] -Measurement procedures for Qc1, Qc2, and Qw1- Here, Qc1, Qc2, and Qw1 are obtained as follows for the toner to be measured in accordance with ASTM D3418 - 8 (2008). First, set 10 mg of the toner to be measured in a differential scanning calorimeter (manufactured by Shimadzu Corporation: DSC - 60A) equipped with an automatic tangent processing system, heat from room temperature (25°C) to 150°C at a heating rate of 10°C / min, and hold at 150°C for 5 minutes to obtain the heating spectrum (DSC curve) in the first heating process. Subsequently, use liquid nitrogen to lower the temperature to 0°C at a cooling rate of -10°C / min and hold at 0°C for 5 minutes. Then, heat to 150°C at a heating rate of 10°C / min to obtain the heating spectrum (DSC curve) in the second heating process.

[0112] From the two obtained heating rate spectra (DSC curves), identify the endothermic peaks derived from the crystalline resin and the endothermic peaks derived from the release agent. Specifically, by comparing with the DSC charts of the crystalline resin alone and the release agent alone measured in advance, the endothermic peaks present near the same temperature are regarded as the endothermic peaks derived from the crystalline resin. Here, the endothermic peaks indicate those with a half-width within 15 °C. And for each heating rate spectrum, calculate the area of the endothermic peak derived from the crystalline resin as the heat absorption amount, and denote them as Qc1 and Qc2 respectively. Also, for the heating rate spectrum in the first heating process, calculate the area of the endothermic peak derived from the release agent as the heat absorption amount, and denote it as Qw1.

[0113] The area of the endothermic peak is the area of the region enclosed by the baseline and the endothermic peak, in accordance with ASTM D3418 - 8(2008), from the endothermic peak derived from the crystalline resin or the release agent. And by obtaining the heat absorption amount per unit mass of the sample from the area of each endothermic peak, calculate the heat absorption amount derived from the crystalline resin and the heat absorption amount derived from the release agent respectively.

[0114] -Properties of toner particles, etc.- The toner particles may be single-layer structured toner particles, or may be so-called core-shell structured toner particles composed of a core part (core particles) and a coating layer (shell layer) covering the core part. Here, the core-shell structured toner particles may be composed of, for example, a core part containing a binder resin and other additives such as a colorant and a release agent as required, and a coating layer containing a binder resin.

[0115] The volume average particle diameter (D50v) of the toner particles is preferably 2 μm or more and 10 μm or less, and more preferably 4 μm or more and 8 μm or less.

[0116] Note that various average particle diameters and various particle size distribution indices of the toner particles are measured using a Coulter Multisizer II (manufactured by Beckman Coulter), and the electrolyte used is ISOTON-II (manufactured by Beckman Coulter). When measuring, 0.5 mg or more and 50 mg or less of a measurement sample is added to 2 ml of a 5% aqueous solution of a surfactant (sodium alkylbenzene sulfonate is preferred) as a dispersant. This is added to 100 ml or more and 150 ml or less of an electrolytic solution. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for 1 minute, and the particle size distribution of particles having a particle size in the range of 2 μm or more and 60 μm or less is measured using an aperture with an aperture diameter of 100 μm by a Coulter Multisizer II. The number of particles to be sampled is 50,000. Based on the measured particle size distribution, cumulative distributions of volume and number are drawn for the particle size ranges (channels) divided, and the particle size at which the cumulative value becomes 16% is defined as the volume particle size D16v, the number particle size D16p, the particle size at which the cumulative value becomes 50% is defined as the volume average particle size D50v, the cumulative number average particle size D50p, and the particle size at which the cumulative value becomes 84% is defined as the volume particle size D84v and the number particle size D84p. Using these, the volume particle size distribution index (GSDv) is (D84v / D16v) 1 / 2 , and the number particle size distribution index (GSDp) is (D84p / D16p) 1 / 2 and is calculated as such.

[0117] As the average circularity of the toner particles, 0.94 or more and 1.00 or less is preferred, and 0.95 or more and 0.98 or less is more preferred.

[0118] The average circularity of the toner particles is obtained by (circumference equivalent to a circle) / (circumference) [(circumference of a circle having the same projected area as the particle image) / (circumference of the particle projection image)]. Specifically, it is a value measured by the following method. First, the toner particles to be measured are aspirated and collected, a flat flow is formed, and a stroboscopic light emission is instantaneously performed to capture the particle image as a still image, and it is obtained by a flow type particle image analyzer (FPIA-3000 manufactured by Sysmex Corporation) that analyzes the particle image. The number of samplings when obtaining the average circularity is 3,500. When the toner has an external additive, after dispersing the toner (developer) to be measured in water containing a surfactant, ultrasonic treatment is performed to obtain toner particles from which the external additive has been removed.

[0119] (Excipient) Examples of the excipient include inorganic particles. Examples of the inorganic particles include SiO2, TiO2, Al2O3, CuO, ZnO, SnO2, CeO2, Fe2O3, MgO, BaO, CaO, K2O, Na2O, ZrO2, CaO·SiO2, K2O·(TiO2)n, Al2O3·2SiO2, CaCO3, MgCO3, BaSO4, MgSO4, etc.

[0120] The surface of the inorganic particles as the excipient is preferably subjected to a hydrophobization treatment. The hydrophobization treatment is performed, for example, by immersing the inorganic particles in a hydrophobizing agent. The hydrophobizing agent is not particularly limited, and examples thereof include silane-based coupling agents, silicone oils, titanate-based coupling agents, aluminum-based coupling agents, etc. These may be used alone or in combination of two or more. The amount of the hydrophobizing agent is usually, for example, 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the inorganic particles.

[0121] Examples of the excipient also include resin particles (resin particles such as polystyrene, polymethyl methacrylate (PMMA), melamine resin, etc.), cleaning agents (for example, metal salts of higher fatty acids represented by zinc stearate, particles of fluorine-based high molecular weight substances), etc.

[0122] The addition amount of the excipient is preferably 0.01% by mass or more and 5% by mass or less, more preferably 0.01% by mass or more and 2.0% by mass or less, with respect to the toner particles.

[0123] (Method for manufacturing toner) Next, the method for manufacturing the toner according to this embodiment will be described. The toner according to this embodiment is obtained by adding an excipient to toner particles after manufacturing the toner particles.

[0124] The toner particles may be manufactured by either a dry process (e.g., kneading and pulverizing method, etc.) or a wet process (e.g., aggregation and coalescence method, suspension polymerization method, dissolution and suspension method, etc.). The manufacturing method of the toner particles is not particularly limited to these methods, and well-known manufacturing methods are adopted. Among these, it is preferable to obtain toner particles by the aggregation and coalescence method.

[0125] (Method for manufacturing toner) Next, the method for manufacturing the toner according to the present embodiment will be described. The toner according to the present embodiment is obtained by performing an annealing treatment on the obtained toner particles after manufacturing the toner particles, and externally adding an external additive to the toner particles after the annealing treatment.

[0126] The toner particles may be manufactured by either a dry process (e.g., kneading and pulverizing method, etc.) or a wet process (e.g., aggregation and coalescence method, suspension polymerization method, dissolution and suspension method, etc.). The manufacturing method of the toner particles is not particularly limited to these methods, and well-known manufacturing methods are adopted.

[0127] First, a method for manufacturing toner particles by the aggregation and coalescence method will be described. A step of preparing a resin particle dispersion liquid in which resin particles serving as a binder resin are dispersed (resin particle dispersion liquid preparation step), and in the resin particle dispersion liquid (in the dispersion liquid after mixing other particle dispersion liquids as necessary), aggregating the resin particles (and other particles as necessary) to form aggregated particles (aggregated particle formation step), and heating the aggregated particle dispersion liquid in which the aggregated particles are dispersed to fuse and coalesce the aggregated particles to form toner particles (fusion and coalescence step). Through these steps, toner particles are manufactured. Here, as the resin particle dispersion liquid, an amorphous resin particle dispersion liquid in which amorphous resin particles are dispersed and a crystalline resin particle dispersion liquid in which crystalline resin particles are dispersed are applicable. Note that as the resin particle dispersion liquid, an amorphous resin particle dispersion liquid in which resin particles containing an amorphous resin and a crystalline resin are dispersed may also be applicable.

[0128] Details of each step will be described below. In the following description, a method for obtaining toner particles containing a colorant (i.e., a dye and, if necessary, a pigment) and a release agent will be described. Of course, other additives other than the colorant and the release agent may be used.

[0129] - Resin Particle Dispersion Preparation Step - First, together with a resin particle dispersion in which resin particles serving as a binder resin are dispersed, for example, a colorant dispersion in which a colorant is dispersed and a release agent particle dispersion in which release agent particles are dispersed are prepared.

[0130] Here, the resin particle dispersion is prepared, for example, by dispersing resin particles in a dispersion medium with a surfactant.

[0131] Examples of the dispersion medium used for the resin particle dispersion include aqueous media. Examples of the aqueous medium include water such as distilled water and ion-exchanged water, and alcohols. These may be used alone or in combination of two or more.

[0132] Examples of the surfactant include anionic surfactants such as sulfate ester salts, sulfonate salts, phosphate esters, and soaps; cationic surfactants such as amine salts and quaternary ammonium salts; nonionic surfactants such as polyethylene glycols, alkylphenol ethylene oxide adducts, and polyhydric alcohols. Among these, in particular, anionic surfactants and cationic surfactants can be mentioned. The nonionic surfactant may be used in combination with an anionic surfactant or a cationic surfactant. The surfactant may be used alone or in combination of two or more.

[0133] In the resin particle dispersion, examples of the method for dispersing the resin particles in the dispersion medium include general dispersion methods such as a rotary shear type homogenizer and a ball mill, a sand mill, and a dyno mill having media. Also, depending on the type of resin particles, for example, the phase inversion emulsification method may be used to disperse the resin particles in the resin particle dispersion. The phase inversion emulsification method is a method in which a resin to be dispersed is dissolved in a hydrophobic organic solvent in which the resin is soluble, a base is added to the organic continuous phase (O phase), neutralized, and then an aqueous medium (W phase) is introduced. By doing so, the resin is converted from W / O to O / W (so-called phase inversion), becoming a discontinuous phase, and the resin is dispersed in the form of particles in the aqueous medium.

[0134] The volume average particle diameter of the resin particles dispersed in the resin particle dispersion is preferably, for example, 0.01 μm or more and 1 μm or less, more preferably 0.08 μm or more and 0.8 μm or less, and even more preferably 0.1 μm or more and 0.6 μm or less. The volume average particle diameter of the resin particles is measured using the particle size distribution obtained by measurement with a laser diffraction particle size distribution measuring device (for example, LA-700 manufactured by Horiba, Ltd.). For the divided particle size ranges (channels), the cumulative distribution is drawn from the small particle size side with respect to the volume, and the particle diameter at which the cumulative value reaches 50% with respect to all the particles is measured as the volume average particle diameter D50v. The volume average particle diameter of the particles in other dispersions is also measured in the same manner.

[0135] The content of the resin particles contained in the resin particle dispersion is preferably, for example, 5% by mass or more and 50% by mass or less, more preferably 10% by mass or more and 40% by mass or less.

[0136] In the same manner as the resin particle dispersion, for example, a colorant dispersion and a release agent particle dispersion are also prepared. That is, regarding the volume average particle diameter, dispersion medium, dispersion method, and content of the particles in the resin particle dispersion, the same applies to the colorant dispersed in the colorant dispersion and the release agent particles dispersed in the release agent particle dispersion.

[0137] - Agglomerate Particle Formation Step - Next, the colorant dispersion and the release agent particle dispersion are mixed with the resin particle dispersion. Then, in the mixed dispersion, the resin particles, the colorant, and the release agent particles are hetero-aggregated to form agglomerate particles containing the resin particles, the colorant, and the release agent particles, which have a diameter close to the diameter of the target toner particles.

[0138] Specifically, for example, a flocculant is added to the mixed dispersion liquid, the pH of the mixed dispersion liquid is adjusted to be acidic (for example, the pH is 2 or more and 5 or less), and a dispersion stabilizer is added as necessary. Then, it is heated to a temperature of the glass transition temperature of the resin particles (specifically, for example, the glass transition temperature of the resin particles is -30°C or more and -10°C or less), and the particles dispersed in the mixed dispersion liquid are aggregated to form aggregated particles. In the aggregated particle formation step, for example, the flocculant may be added at room temperature (for example, 25°C) while stirring the mixed dispersion liquid with a rotary shear homogenizer, the pH of the mixed dispersion liquid is adjusted to be acidic (for example, the pH is 2 or more and 5 or less), and a dispersion stabilizer is added as necessary. Then, the above heating may be performed.

[0139] Examples of the flocculant include surfactants having a reverse polarity to the surfactant used as a dispersant added to the mixed dispersion liquid, inorganic metal salts, and metal complexes having a valence of 2 or more. In particular, when a metal complex is used as the flocculant, the amount of surfactant used is reduced and the charging characteristics are improved. An additive that forms a complex or a similar bond with the metal ion of the flocculant may be used as necessary. As this additive, a chelating agent is preferably used.

[0140] Examples of the inorganic metal salts include metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, aluminum sulfate, and inorganic metal salt polymers such as polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide. As the chelating agent, a water-soluble chelating agent may be used. Examples of the chelating agent include oxycarboxylic acids such as tartaric acid, citric acid, and gluconic acid, iminodiacetic acid (IDA), nitrilotriacetic acid (NTA), and ethylenediaminetetraacetic acid (EDTA). The addition amount of the chelating agent is preferably 0.01 part by mass or more and 5.0 parts by mass or less, and more preferably 0.1 part by mass or more and less than 3.0 parts by mass, based on 100 parts by mass of the resin particles.

[0141] -Fusion and integration step- Next, with respect to the aggregated particle dispersion liquid in which the aggregated particles are dispersed, for example, it is heated to a temperature equal to or higher than the glass transition temperature of the resin particles (for example, a temperature equal to or higher than 10 to 30 °C higher than the glass transition temperature of the resin particles), so that the aggregated particles are fused and united to form toner particles.

[0142] Through the above steps, toner particles are obtained. Note that after obtaining the aggregated particle dispersion liquid in which the aggregated particles are dispersed, the aggregated particle dispersion liquid and the resin particle dispersion liquid in which the resin particles are dispersed are further mixed, and they are aggregated so that the resin particles further adhere to the surface of the aggregated particles to form second aggregated particles. Then, the second aggregated particle dispersion liquid in which the second aggregated particles are dispersed is heated to fuse and unite the second aggregated particles to form toner particles having a core / shell structure. Toner particles may be manufactured through these steps. However, the resin particles adhering to the surface of the aggregated particles are preferably amorphous resin particles.

[0143] Here, after the fusion and unification step is completed, the toner particles formed in the solution are dried through known washing steps, solid-liquid separation steps, and drying steps to obtain toner particles in a dried state. In the washing step, it is preferable to perform substitution washing sufficiently with ion-exchanged water from the viewpoint of chargeability. Also, in the solid-liquid separation step, there is no particular limitation, but from the viewpoint of productivity, it is preferable to perform suction filtration, pressure filtration, etc. Also, there is no particular limitation on the drying method in the drying step, but from the viewpoint of productivity, it is preferable to perform freeze drying, airflow drying, fluidized drying, vibration type fluidized drying, etc.

[0144] Next, the case of manufacturing toner particles containing a urea-modified polyester resin (urea-modified amorphous polyester resin) will be described. Toner particles containing a urea-modified polyester resin can be obtained by the following dissolution and suspension method. Here, a method for obtaining toner particles containing a urea-modified polyester resin (urea-modified amorphous polyester resin) and an unmodified crystalline polyester resin as the binder resin is described. However, the toner particles may contain an unmodified amorphous polyester resin as the binder resin. Further, a method for obtaining toner particles containing a colorant and releasability is described. The colorant and releasability are components contained in the toner particles as required.

[0145] [Oil phase liquid preparation step] Prepare an oil phase liquid by dissolving or dispersing a toner particle material containing an unmodified crystalline polyester resin (hereinafter also simply referred to as "crystalline polyester resin"), an amorphous polyester prepolymer having an isocyanate group, an amine compound, a colorant, and a release agent in an organic solvent (oil phase liquid preparation step). In this oil phase liquid preparation step, it is a step of dissolving or dispersing the toner particle material in an organic solvent to obtain a mixed liquid of the toner material.

[0146] The oil-phase liquid can be prepared by the following methods: 1) dissolving or dispersing toner materials in an organic solvent all at once; 2) kneading toner materials in advance and then dissolving or dispersing the kneaded product in an organic solvent; 3) dissolving a crystalline polyester resin, an amorphous polyester prepolymer having an isocyanate group, and an amine compound in an organic solvent, and then dispersing a colorant and a release agent in this organic solvent for adjustment; 4) dispersing a colorant and a release agent in an organic solvent, and then dissolving a crystalline polyester resin, an amorphous polyester prepolymer having an isocyanate group, and an amine compound in this organic solvent for preparation; 5) dissolving or dispersing toner particle materials other than an amorphous polyester prepolymer having an isocyanate group and an amine compound (crystalline polyester resin, colorant, and release agent) in an organic solvent, and then dissolving an amorphous polyester prepolymer having an isocyanate group and an amine compound in this organic solvent for preparation; 6) dissolving or dispersing toner particle materials other than an amorphous polyester prepolymer having an isocyanate group or an amine compound (crystalline polyester resin, colorant, and release agent) in an organic solvent, and then dissolving an amorphous polyester prepolymer having an isocyanate group or an amine compound in this organic solvent for preparation, etc. Note that the method for preparing the oil-phase liquid is not limited to these.

[0147] Examples of the organic solvent for the oil-phase liquid include ester solvents such as methyl acetate and ethyl acetate; ketone solvents such as methyl ethyl ketone and methyl isopropyl ketone; aliphatic hydrocarbon solvents such as hexane and cyclohexane; halogenated hydrocarbon solvents such as dichloromethane, chloroform, and trichloroethylene. These organic solvents can dissolve the binder resin and preferably have a solubility in water of 0% by mass or more and 30% by mass or less and a boiling point of 100°C or less. Among these organic solvents, ethyl acetate is preferred.

[0148] - Suspension Preparation Step - Next, the obtained oil-phase liquid is dispersed in the aqueous-phase liquid to prepare a suspension (suspension preparation step). Then, together with the preparation of the suspension, an amorphous polyester prepolymer having isocyanate groups is reacted with an amine compound. And a urea-modified polyester resin is produced by this reaction. Note that this reaction involves at least one of a cross-linking reaction and an elongation reaction of the molecular chain. Note that the reaction between the amorphous polyester prepolymer having isocyanate groups and the amine compound may be carried out together with the organic solvent removal step described later. Here, the reaction conditions are selected according to the reactivity between the isocyanate group structure of the amorphous polyester prepolymer and the amine compound. As an example, the reaction time is preferably 10 minutes or more and 40 hours or less, and more preferably 2 hours or more and 24 hours or less. The reaction temperature is preferably 0°C or more and 150°C or less, and more preferably 40°C or more and 98°C or less. Note that for the production of the urea-modified polyester resin, a known catalyst (such as dibutyltin laurate, dioctyltin laurate, etc.) may be used as necessary. That is, the catalyst may be added to the oil phase liquid or the suspension.

[0149] Examples of the aqueous phase liquid include an aqueous phase liquid in which a particle dispersant such as an organic particle dispersant or an inorganic particle dispersant is dispersed in an aqueous solvent. The aqueous phase liquid also includes an aqueous phase liquid in which a particle dispersant is dispersed in an aqueous solvent and a polymer dispersant is dissolved in the aqueous solvent. Note that well-known additives such as surfactants may be added to the aqueous phase liquid.

[0150] Examples of the aqueous solvent include water (for example, usually ion-exchanged water, distilled water, pure water). The aqueous solvent may be a solvent containing an organic solvent such as alcohol (such as methanol, isopropyl alcohol, ethylene glycol), dimethylformamide, tetrahydrofuran, cellosolves (such as methyl cellosolve), and lower ketones (such as acetone, methyl ethyl ketone) together with water.

[0151] Examples of the organic particle dispersant include hydrophilic organic particle dispersants. Examples of the organic particle dispersant include particles such as poly(alkyl (meth)acrylate) resins (e.g., polymethyl methacrylate resin), polystyrene resins, and poly(styrene-acrylonitrile) resins. Examples of the organic particle dispersant also include particles of styrene acrylic resins.

[0152] Examples of the inorganic particle dispersant include hydrophilic inorganic particle dispersants. Specifically, examples of the inorganic particle dispersant include particles such as silica, alumina, titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, clay, diatomaceous earth, and bentonite, with calcium carbonate particles being preferred. The inorganic particle dispersant may be used alone or in combination of two or more.

[0153] The surface of the particle dispersant may be surface-treated with a polymer having a carboxyl group. Examples of the polymer having a carboxyl group include copolymers of at least one selected from α,β-monoethylenically unsaturated carboxylic acids or salts (such as alkali metal salts, alkaline earth metal salts, ammonium salts, and amine salts) in which the carboxyl groups of α,β-monoethylenically unsaturated carboxylic acids are neutralized with alkali metals, alkaline earth metals, ammonium, amines, etc., and α,β-monoethylenically unsaturated carboxylic acid esters. Examples of the polymer having a carboxyl group also include salts (such as alkali metal salts, alkaline earth metal salts, ammonium salts, and amine salts) in which the carboxyl groups of copolymers of α,β-monoethylenically unsaturated carboxylic acids and α,β-monoethylenically unsaturated carboxylic acid esters are neutralized with alkali metals, alkaline earth metals, ammonium, amines, etc. The polymer having a carboxyl group may be used alone or in combination of two or more.

[0154] Typical α,β-monoethylenically unsaturated carboxylic acids include α,β-unsaturated monocarboxylic acids (such as acrylic acid, methacrylic acid, crotonic acid, etc.), α,β-unsaturated dicarboxylic acids (such as maleic acid, fumaric acid, itaconic acid, etc.). Also, typical α,β-monoethylenically unsaturated carboxylic acid esters include alkyl esters of (meth)acrylic acid, (meth)acrylates having an alkoxy group, (meth)acrylates having a cyclohexyl group, (meth)acrylates having a hydroxy group, polyalkylene glycol mono(meth)acrylates, etc.

[0155] As the polymer dispersant, a hydrophilic polymer dispersant can be mentioned. Specifically, as the polymer dispersant, a polymer dispersant having a carboxyl group and no lipophilic group (such as a hydroxypropoxy group, a methoxy group, etc.) (for example, water-soluble cellulose ethers such as carboxymethyl cellulose, carboxyethyl cellulose, etc.) can be mentioned.

[0156] - Solvent removal step - Next, an organic solvent is removed from the obtained suspension to obtain a toner particle dispersion (solvent removal step). In this solvent removal step, it is a step of removing the organic solvent contained in the droplets of the aqueous phase liquid dispersed in the suspension to generate toner particles. The removal of the organic solvent from the suspension may be performed immediately after the suspension preparation step, or may be performed after 1 minute or more has elapsed after the completion of the suspension preparation step. In the solvent removal step, it is preferable to remove the organic solvent from the suspension by cooling or heating the obtained suspension, for example, in the range of 0°C or higher and 100°C or lower.

[0157] Specific methods for removing the organic solvent include the following methods. (1) A method of blowing an air stream onto the suspension to forcibly update the gas phase on the suspension surface. In this case, a gas may be blown into the suspension. (2) A method of reducing the pressure. In this case, the gas phase on the suspension surface may be forcibly updated by filling with a gas, or a gas may be further blown into the suspension.

[0158] Through the above steps, toner particles are obtained. Here, after the solvent removal step, the toner particles formed in the toner particle dispersion are obtained as dried toner particles through known cleaning steps, solid-liquid separation steps, and drying steps. In the cleaning step, it is preferable to perform substitution cleaning sufficiently with ion-exchanged water from the viewpoint of chargeability. Also, the solid-liquid separation step is not particularly limited, but from the viewpoint of productivity, it is preferable to perform suction filtration, pressure filtration, etc. Also, the drying step is not particularly limited in method, but from the viewpoint of productivity, it is preferable to perform freeze drying, airflow drying, fluidized drying, vibration type fluidized drying, etc.

[0159] Next, the annealing step will be described. In the production of toner particles, the toner particles obtained through the above steps are subjected to an annealing treatment (heat treatment).

[0160] Specifically, for example, the obtained toner particles are heated to a temperature of 50°C or higher and 60°C or lower, and held at that temperature for a range of 1 hour or more and 4 hours or less. By this treatment, the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is likely to be 15% or less.

[0161] Note that the timing of the annealing step is not limited to the above, and for example, it may be carried out in a dispersion liquid in which toner particles are formed, or in a slurry state in which the amount of the solvent in the dispersion liquid is reduced.

[0162] And the toner according to this embodiment is manufactured, for example, by adding and mixing an external additive to the obtained dried toner particles after the annealing treatment. The mixing may be carried out, for example, by a V blender, a Henschel mixer, a Lodige mixer, etc. Further, if necessary, coarse particles of the toner may be removed using a vibrating sieve, an air classifier, etc.

[0163] <Electrostatic charge image developer> The electrostatic charge image developer according to this embodiment contains at least the toner according to this embodiment. The electrostatic charge image developer according to this embodiment may be a one-component developer containing only the toner according to this embodiment, or a two-component developer in which the toner and a carrier are mixed.

[0164] There is no particular limitation on the carrier, 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. Note that 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.

[0165] Examples of the magnetic powder include magnetic metals such as iron, nickel, and cobalt, and magnetic oxides such as ferrite and magnetite.

[0166] 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 containing an organosiloxane bond, fluororesin, polyester, polycarbonate, phenol resin, epoxy resin, and the like. Note that the coating resin and the matrix resin may contain other additives such as conductive particles. Examples of the conductive particles include metals such as gold, silver, and copper, and particles such as carbon black, titanium oxide, zinc oxide, tin oxide, barium sulfate, aluminum borate, and potassium titanate.

[0167] Here, to coat the surface of the core material with a coating resin, methods such as coating with a coating resin and, if necessary, a coating layer forming solution in which various additives are dissolved in an appropriate solvent can be mentioned. The solvent is not particularly limited and may be selected in consideration of the coating resin to be used, coating applicability, etc. As specific resin coating methods, there are 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, etc.

[0168] In the two-component developer, the mixing ratio (mass ratio) of toner and carrier is preferably toner:carrier = 1:100 to 30:100, more preferably 3:100 to 20:100.

[0169] <Image forming apparatus / Image forming method> The image forming apparatus / image forming method according to this embodiment will be described. The image forming apparatus according to this embodiment includes an image carrier, a charging means for charging the surface of the image carrier, an electrostatic charge image forming means for forming an electrostatic charge image on the charged surface of the image carrier, a developing means for accommodating an electrostatic charge image developer and developing the electrostatic charge image formed on the surface of the image carrier as a toner image with the electrostatic charge image developer, a transfer means for transferring the toner image formed on the surface of the image carrier to the surface of a recording medium, and a fixing means for fixing the toner image transferred to the surface of the recording medium. And, as the electrostatic charge image developer, the electrostatic charge image developer according to this embodiment is applied.

[0170] The fixing means has a fixing member and a pressing member for pressing the outer peripheral surface of the fixing member and sandwiching the recording medium having an unfixed toner image formed on its surface together with the fixing member, and preferably does not have a coating mechanism for applying a release agent to the surface of the fixing member.

[0171] In the image forming apparatus according to the present embodiment, there are a charging step of charging the surface of the image carrier, an electrostatic charge image forming step of forming an electrostatic charge image on the charged surface of the image carrier, a developing step of developing the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer according to the present embodiment, a transfer step of transferring the toner image formed on the surface of the image carrier to the surface of a recording medium, and a fixing step of fixing the toner image transferred to the surface of the recording medium. An image forming method (image forming method according to the present embodiment) is implemented.

[0172] The image forming apparatus according to the present embodiment is a direct transfer type apparatus that directly transfers the toner image formed on the surface of the image carrier to a recording medium; an intermediate transfer type apparatus that first transfers the toner image formed on the surface of the image carrier to the surface of an intermediate transfer member and then secondarily transfers the toner image transferred to the surface of the intermediate transfer member to the surface of a recording medium; an apparatus provided with cleaning means for cleaning the surface of the image carrier before charging after the transfer of the toner image; an apparatus provided with charge elimination means for irradiating the surface of the image carrier with charge elimination light for charge elimination before charging after the transfer of the toner image, etc. Well-known image forming apparatuses are applicable. In the case of an intermediate transfer type apparatus, the transfer means has, for example, a configuration including an intermediate transfer member on which a toner image is transferred to the surface, a primary transfer means for primarily transferring the toner image formed on the surface of the image carrier to the surface of the intermediate transfer member, and a secondary transfer means for secondarily transferring the toner image transferred to the surface of the intermediate transfer member to the surface of a recording medium.

[0173] Note that, in the image forming apparatus according to the present embodiment, for example, a portion including developing means may be a cartridge structure (process cartridge) that is detachable from the image forming apparatus. As the process cartridge, for example, a process cartridge provided with developing means containing the electrostatic charge image developer according to the present embodiment is preferably used.

[0174] Hereinafter, an example of the image forming apparatus according to the present embodiment is shown, but it is not necessarily limited thereto. Note that the main parts shown in the figure are described, and the description of the others is omitted.

[0175] FIG. 1 is a schematic configuration diagram showing an image forming apparatus according to the present embodiment. The image forming apparatus shown in FIG. 1 includes electrophotographic first to fourth image forming units 10Y, 10M, 10C, 10K (image forming means) that output images of respective colors of yellow (Y), magenta (M), cyan (C), and black (K) based on color-separated image data. These image forming units (hereinafter, may be simply referred to as "units") 10Y, 10M, 10C, 10K are arranged side by side at a predetermined distance from each other in the horizontal direction. Note that these units 10Y, 10M, 10C, 10K may be process cartridges that are detachable from the image forming apparatus.

[0176] Above each of the units 10Y, 10M, 10C, 10K in the drawing, an intermediate transfer belt 20 as an intermediate transfer member extends through each unit. The intermediate transfer belt 20 is provided by being wound around a driving roll 22 and a support roll 24 that is in contact with the inner surface of the intermediate transfer belt 20 and is arranged at a distance from each other in the left-to-right direction in the drawing, and is configured to travel in the direction from the first unit 10Y to the fourth unit 10K. Note that a force is applied to the support roll 24 in a direction away from the driving roll 22 by a spring or the like (not shown), and tension is applied to the intermediate transfer belt 20 wound around both of them. Further, an intermediate transfer member cleaning device 30 is provided on the image holding body side surface of the intermediate transfer belt 20 so as to face the driving roll 22. In addition, each of the developing devices (developing means) 4Y, 4M, 4C, 4K of the units 10Y, 10M, 10C, 10K is supplied with toner containing four colors of toner of yellow, magenta, cyan, and black stored in toner cartridges 8Y, 8M, 8C, 8K.

[0177] Since the first to fourth units 10Y, 10M, 10C, and 10K have the same configuration, the first unit 10Y that forms a yellow image disposed on the upstream side in the intermediate transfer belt running direction will be described as a representative here. Note that for parts equivalent to the first unit 10Y, reference numerals with magenta (M), cyan (C), and black (K) attached instead of yellow (Y) are used to omit the description of the second to fourth units 10M, 10C, and 10K.

[0178] The first unit 10Y has a photoreceptor 1Y that acts as an image holding member. Around the photoreceptor 1Y, there are a charging roll (an example of charging means) 2Y that charges the surface of the photoreceptor 1Y to a predetermined potential, an exposure device (an example of electrostatic charge image forming means) 3 that exposes the charged surface with a laser beam 3Y based on a color-separated image signal to form an electrostatic charge image, a developing device (an example of developing means) 4Y that supplies toner charged to the electrostatic charge image to develop the electrostatic charge image, a primary transfer roll 5Y (an example of primary transfer means) that transfers the developed toner image onto the intermediate transfer belt 20, and a photoreceptor cleaning device (an example of cleaning means) 6Y that removes the toner remaining on the surface of the photoreceptor 1Y after primary transfer, which are arranged in order. Note that the primary transfer roll 5Y is disposed inside the intermediate transfer belt 20 and provided at a position facing the photoreceptor 1Y. Further, a bias power source (not shown) for applying a primary transfer bias is connected to each of the primary transfer rolls 5Y, 5M, 5C, and 5K. Each bias power source varies the transfer bias applied to each primary transfer roll under the control of a control unit (not shown).

[0179] Hereinafter, the operation of forming a yellow image in the first unit 10Y will be described. First, prior to the operation, the surface of the photoreceptor 1Y is charged to a potential of -600 V to -800 V by the charging roll 2Y. The photoreceptor 1Y has conductivity (for example, volume resistivity at 20°C: 1×10 -6It is formed by laminating a photosensitive layer on a substrate (with a resistance of less than Ωcm). This photosensitive layer is usually of high resistance (the resistance of a general resin), but when irradiated with a laser beam 3Y, it has the property that the specific resistance of the irradiated portion changes. Therefore, a laser beam 3Y is output via an exposure device 3 according to the yellow image data sent from a control unit (not shown) to the surface of the charged photoreceptor 1Y. The laser beam 3Y is irradiated onto the photosensitive layer on the surface of the photoreceptor 1Y, thereby forming an electrostatic charge image of a yellow image pattern on the surface of the photoreceptor 1Y.

[0180] An electrostatic charge image is an image formed on the surface of the photoreceptor 1Y by charging. Due to the laser beam 3Y, the specific resistance of the irradiated portion of the photosensitive layer decreases, and the charged charges on the surface of the photoreceptor 1Y flow, while the charges in the portion not irradiated by the laser beam 3Y remain, forming a so-called negative latent image. The electrostatic charge image formed on the photoreceptor 1Y is rotated to a predetermined development position as the photoreceptor 1Y travels. And at this development position, the electrostatic charge image on the photoreceptor 1Y is visualized as a toner image (developed image) by a developing device 4Y.

[0181] Inside the developing device 4Y, for example, an electrostatic charge image developer containing at least yellow toner and carrier is accommodated. The yellow toner is triboelectrically charged by being agitated inside the developing device 4Y and has the same polarity (negative polarity) charge as the charged charges on the photoreceptor 1Y and is held on a developer roll (an example of a developer holding body). And as the surface of the photoreceptor 1Y passes through the developing device 4Y, the yellow toner electrostatically adheres to the discharged latent image portion on the surface of the photoreceptor 1Y, and the latent image is developed by the yellow toner. The photoreceptor 1Y on which a yellow toner image is formed continues to travel at a predetermined speed, and the toner image developed on the photoreceptor 1Y is conveyed to a predetermined primary transfer position.

[0182] When the yellow toner image on the photoreceptor 1Y is conveyed to primary transfer, a primary transfer bias is applied to the primary transfer roll 5Y, and an electrostatic force directed from the photoreceptor 1Y toward the primary transfer roll 5Y acts on the toner image, transferring the toner image on the photoreceptor 1Y onto the intermediate transfer belt 20. The transfer bias applied at this time has a polarity (+) opposite to the polarity (-) of the toner. For example, in the first unit 10Y, it is controlled to +10 μA by a control unit (not shown). On the other hand, the toner remaining on the photoreceptor 1Y is removed and recovered by the photoreceptor cleaning device 6Y.

[0183] Also, the primary transfer biases applied to the primary transfer rolls 5M, 5C, and 5K after the second unit 10M are also controlled according to the first unit. In this way, the intermediate transfer belt 20 onto which the yellow toner image has been transferred in the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of each color are overlapped and multi-transferred.

[0184] The intermediate transfer belt 20 onto which the four-color toner images have been multi-transferred through the first to fourth units reaches the secondary transfer section composed of the intermediate transfer belt 20, the support roll 24 in contact with the inner surface of the intermediate transfer belt, and the secondary transfer roll (an example of secondary transfer means) 26 arranged on the image holding surface side of the intermediate transfer belt 20. On the other hand, the recording paper (an example of a recording medium) P is fed at a predetermined timing to the gap where the secondary transfer roll 26 and the intermediate transfer belt 20 are in contact via a supply mechanism, and a secondary transfer bias is applied to the support roll 24. The transfer bias applied at this time has the same polarity (-) as the polarity (-) of the toner, and an electrostatic force directed from the intermediate transfer belt 20 toward the recording paper P acts on the toner image, transferring the toner image on the intermediate transfer belt 20 onto the recording paper P. Note that the secondary transfer bias at this time is determined according to the resistance detected by resistance detection means (not shown) for detecting the resistance of the secondary transfer section and is voltage-controlled.

[0185] Thereafter, the recording paper P is fed into the pressure contact portion (nip portion) of a pair of rolls (an example of a fixing member and a pressing member) in the fixing device (an example of a fixing means) 28, and the toner image is fixed onto the recording paper P to form a fixed image. Here, it is preferable that the fixing device 28 does not have a coating mechanism for applying a release agent to the surface of the fixing roll.

[0186] Examples of the recording paper P for transferring the toner image include plain paper used in electrophotographic copiers, printers, etc. Recording media other than the recording paper P also include OHP sheets and the like. In order to further improve the smoothness of the image surface after fixing, it is preferable that the surface of the recording paper P is also smooth. For example, coated paper with the surface of plain paper coated with resin or the like, art paper for printing, etc. are preferably used.

[0187] The recording paper P on which the fixing of the color image is completed is carried out toward the discharge portion, and a series of color image forming operations are terminated.

[0188] <Process cartridge / Toner cartridge> The process cartridge according to this embodiment will be described. The process cartridge according to this embodiment houses the electrostatic charge image developer according to this embodiment, and includes developing means for developing the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer, and is a process cartridge that is detachable from the image forming apparatus.

[0189] Note that the process cartridge according to this embodiment is not limited to the above configuration, and may be a configuration including a developing device and at least one selected from other means such as an image carrier, charging means, electrostatic charge image forming means, and transfer means, etc. as necessary.

[0190] Hereinafter, an example of the process cartridge according to this embodiment is shown, but it is not limited thereto. Note that the main parts shown in the figure will be described, and the others will be omitted from the description.

[0191] FIG. 2 is a schematic configuration diagram showing a process cartridge according to the present embodiment. The process cartridge 200 shown in FIG. 2 is configured by integrally combining and holding, for example, a photosensitive member 107 (an example of an image holding member), a charging roll 108 (an example of charging means) provided around the photosensitive member 107, a developing device 111 (an example of developing means), and a photosensitive cleaning device 113 (an example of cleaning means) with a housing 117 provided with an attachment rail 116 and an opening 118 for exposure, and is cartridge-ized. In FIG. 2, 109 indicates an exposure device (an example of electrostatic charge image forming means), 112 indicates a transfer device (an example of transfer means), 115 indicates a fixing device (an example of fixing means), and 300 indicates a recording paper (an example of a recording medium).

[0192] Next, the toner cartridge according to the present embodiment will be described. The toner cartridge according to the present embodiment is a toner cartridge that houses the toner according to the present embodiment and is detachable from the image forming apparatus. The toner cartridge houses replenishing toner for supplying to developing means provided in the image forming apparatus.

[0193] The image forming apparatus shown in FIG. 1 is an image forming apparatus having a configuration in which toner cartridges 8Y, 8M, 8C, and 8K are detachable, and the developing devices 4Y, 4M, 4C, and 4K are connected to toner cartridges corresponding to the respective developing devices (colors) by toner supply pipes (not shown). When the amount of toner housed in the toner cartridge becomes small, the toner cartridge is replaced.

Example

[0194] Examples will be described below, but the present invention is not limited to these examples. In the following description, unless otherwise specified, all "parts" and "%" are based on mass.

[0195] <Preparation of dispersion liquid> (Preparation of amorphous polyester resin particle dispersion liquid (A1)) · Terephthalic acid: 30 mol parts · Fumaric acid: 70 mol parts · Bisphenol A ethylene oxide adduct: 10 mol parts · Bisphenol A propylene oxide adduct: 90 mol parts The above materials were charged into a 5-liter flask equipped with a stirring device, a nitrogen inlet tube, a temperature sensor, and a rectification column. It took 1 hour to raise the temperature to 220°C, and 1 part of titanium tetraethoxide was added to 100 parts of the above materials. While distilling off the generated water, it took 0.5 hour to raise the temperature to 230°C, and after continuing the dehydration condensation reaction at this temperature for 1 hour, the reaction product was cooled. Thus, an amorphous polyester resin (A1) having a weight average molecular weight of 20,000, an acid value of 13 mgKOH / g, and a glass transition temperature of 60°C was synthesized.

[0196] Next, 40 parts of ethyl acetate and 25 parts of 2-butanol were charged into a container equipped with a temperature control means and a nitrogen replacement means to obtain a mixed solvent. Then, 100 parts of the amorphous polyester resin (A1) was gradually added and dissolved, and 10% by mass aqueous ammonia solution (equivalent to 3 times the molar ratio with respect to the acid value of the resin) was added thereto and stirred for 30 minutes.

[0197] Then, the inside of the container was replaced with dry nitrogen, the temperature was maintained at 40°C, and while stirring the mixed solution, 400 parts of ion-exchanged water was dropped at a rate of 2 parts / minute to perform emulsification. After the dropping was completed, the emulsion was returned to room temperature (20°C to 25°C), and bubbling was performed with dry nitrogen for 48 hours while stirring to reduce ethyl acetate and 2-butanol to 1,000 ppm or less, and a resin particle dispersion liquid in which resin particles having a volume average particle diameter of 200 nm were dispersed was obtained. Ion-exchanged water was added to the resin particle dispersion liquid to adjust the solid content to 20% by mass, and an amorphous polyester resin particle dispersion liquid (A1) was obtained.

[0198] (Preparation of amorphous polyester resin particle dispersion liquid (A2)) In the preparation of the amorphous polyester resin particle dispersion (A1), except that the addition amount of the bisphenol A ethylene oxide adduct was changed to 30 mol parts, the addition amount of the bisphenol A propylene oxide adduct was changed to 70 mol parts, and it took 1 hour to raise the temperature to 210 °C after charging the materials, the amorphous polyester resin particle dispersion (A2) was obtained in the same procedure as the amorphous polyester resin particle dispersion (A1). The obtained amorphous polyester resin (A2) had a weight average molecular weight of 16,000, an acid value of 13.4 mg KOH / g, and a glass transition temperature of 49 °C.

[0199] (Preparation of crystalline polyester resin particle dispersion (A3)) In the preparation of the amorphous polyester resin particle dispersion (A1), except that the addition amount of the bisphenol A ethylene oxide adduct was changed to 40 mol parts, the addition amount of the bisphenol A propylene oxide adduct was changed to 60 mol parts, and it took 1 hour to raise the temperature to 200 °C after charging the materials, the amorphous polyester resin particle dispersion (A3) was obtained in the same procedure as the amorphous polyester resin particle dispersion (A1). The obtained amorphous polyester resin (A3) had a weight average molecular weight of 14,000, an acid value of 14.1 mg KOH / g, and a glass transition temperature of 45 °C.

[0200] (Preparation of crystalline polyester resin particle dispersion (A4)) In the preparation of the amorphous polyester resin particle dispersion (A1), except that the time for raising the temperature to 230 °C while distilling off the generated water was changed to 1.0 hour, the amorphous polyester resin particle dispersion (A4) was obtained in the same procedure as the amorphous polyester resin particle dispersion (A1). The obtained amorphous polyester resin (A4) had a weight average molecular weight of 21,000, an acid value of 13 mg KOH / g, and a glass transition temperature of 60 °C.

[0201] (Preparation of crystalline polyester resin particle dispersion (A1)) · 1,10 - dodecanedioic acid: 50 mol parts · 1,9-Nonanediol: 50 mol parts The above monomer components were placed in a reaction vessel equipped with a stirrer, a thermometer, a condenser, and a nitrogen gas inlet tube. After replacing the inside of the reaction vessel with dry nitrogen gas, 0.25 part of titanium tetrabutoxide (reagent) was added per 100 parts of the monomer components. After stirring and reacting at 170 °C for 3 hours under a nitrogen gas stream, the temperature was further raised to 210 °C over 1 hour, the pressure inside the reaction vessel was reduced to 3 kPa, and stirring and reaction were carried out under reduced pressure for 13 hours to obtain a crystalline polyester resin (A1). The obtained crystalline polyester resin (A1) had a melting temperature Tm of 73.6 °C by DSC, a mass average molecular weight Mw of 25,000, a number average molecular weight Mn of 10,500, and an acid value AV of 10.1 mg KOH / g by GPC.

[0202] Next, 300 parts of the crystalline polyester resin (1), 160 parts of methyl ethyl ketone (solvent), and 100 parts of isopropyl alcohol (solvent) were placed in a 3-liter jacketed reaction tank (manufactured by Tokyo Rika Kikai Co., Ltd.: BJ-30N) equipped with a condenser, a thermometer, a water dropping device, and an anchor blade. While maintaining the temperature at 70 °C in a water-circulating constant temperature bath, the resin was dissolved while stirring and mixing at 100 rpm (dissolved solution preparation step). Thereafter, the stirring rotation speed was set to 150 rpm, the water-circulating constant temperature bath was set to 66 °C, 17 parts of 10% aqueous ammonia (reagent) were added over 10 minutes, and then ion-exchanged water kept at 66 °C was dropped at a rate of 7 parts / minute for a total of 900 parts to cause phase inversion and obtain an emulsion.

[0203] Immediately, 800 parts of the obtained emulsion and 700 parts of ion-exchanged water were placed in a 2-liter eggplant flask and set in an evaporator (Tokyo Rika Kikai Co., Ltd.) equipped with a vacuum control unit via a trap ball. While rotating the eggplant flask, it was heated in a water bath at 60 °C, and the pressure was reduced to 7 kPa while paying attention to bumping to remove the solvent. When the solvent recovery amount reached 1,100 parts, the pressure was returned to normal pressure, and the eggplant flask was cooled with water to obtain a dispersion. There was no solvent odor in the obtained dispersion. The volume-average particle diameter D50v of the resin particles in this dispersion was 130 nm. Thereafter, ion-exchanged water was added to adjust the solid content concentration to 20%, and this was used as the crystalline polyester resin particle dispersion (A1).

[0204] (Preparation of crystalline polyester resin particle dispersion (A2)) In the preparation of the crystalline polyester resin particle dispersion (A1), after stirring and reacting at 170 °C for 3 hours under a nitrogen gas stream, the temperature was further raised to 200 °C over 1 hour, and the crystalline polyester resin particle dispersion (A2) was obtained in the same procedure as the crystalline polyester resin particle dispersion (A1) except for this. In addition, the obtained crystalline polyester resin (A2) had a melting temperature Tm of 69.0 °C by DSC, a mass-average molecular weight Mw of 23,000, a number-average molecular weight Mn of 9,000, and an acid value AV of 10.5 mgKOH / g by GPC.

[0205] (Preparation of crystalline polyester resin particle dispersion (A3)) In the preparation of the crystalline polyester resin particle dispersion (A1), after stirring and reacting at 170 °C for 3 hours under a nitrogen gas stream, the temperature was further raised to 200 °C over 1 hour, the pressure inside the reaction vessel was reduced to 3 kPa, and the crystalline polyester resin particle dispersion (A3) was obtained in the same procedure as the crystalline polyester resin particle dispersion (A1) except for stirring and reacting under reduced pressure for 10 hours. In addition, the obtained crystalline polyester resin (A3) had a melting temperature Tm of 60.0 °C by DSC, a mass-average molecular weight Mw of 20,000, a number-average molecular weight Mn of 8,500, and an acid value AV of 10.8 mgKOH / g by GPC.

[0206] (Preparation of Crystalline Polyester Resin Particle Dispersion (A4)) In the preparation of the crystalline polyester resin particle dispersion (A1), after stirring and reacting at 170 °C for 3 hours under a nitrogen gas stream, the temperature was further raised to 220 °C over 1 hour, the pressure inside the reaction vessel was reduced to 3 kPa, and the stirring reaction was carried out under reduced pressure for 15 hours. Except for this, the crystalline polyester resin particle dispersion (A4) was obtained in the same procedure as the crystalline polyester resin particle dispersion (A1). The obtained crystalline polyester resin (A4) had a melting temperature Tm of 80 °C by DSC, a mass average molecular weight Mw of 27,000, a number average molecular weight Mn of 12,000, and an acid value AV of 9.8 mg KOH / g by GPC.

[0207] (Preparation of Colorant Dispersion (A1)) · Basic dye: Rhodamine B (manufactured by Nippon Kayaku Co., Ltd., Basic Violet 10): 70 parts · Anionic surfactant (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., Neogen RK): 30 parts · Ion-exchanged water: 200 parts The above materials were mixed and dispersed for 10 minutes using a homogenizer (Ultra Turrax T50 manufactured by IKA). Ion-exchanged water was added so that the content of the basic dye in the dispersion was 20% by mass, and a colorant dispersion (A1) in which the basic dye was dispersed was obtained.

[0208] (Preparation of Colorant Dispersion (A2)) · Basic dye: Basic Red 36 (manufactured by Tokyo Chemical Industry Co., Ltd.): 70 parts · Anionic surfactant (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., Neogen RK): 30 parts · Ion-exchanged water: 200 parts The above materials were mixed and dispersed for 10 minutes using a homogenizer (Ultra Turrax T50 manufactured by IKA). Ion-exchanged water was added so that the content of the basic dye in the dispersion was 20% by mass, and a colorant dispersion (A2) in which the basic dye was dispersed was obtained.

[0209] (Preparation of Colorant Dispersion (A3)) · Acid dye: Acid Yellow 23 (manufactured by Tokyo Chemical Industry Co., Ltd.): 70 parts · Anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 30 parts · Ion-exchanged water: 200 parts The above materials were mixed and dispersed for 10 minutes using a homogenizer (Ultra Turrax T50 manufactured by IKA). Ion-exchanged water was added so that the content of the acid dye in the dispersion was 20% by mass, and a colorant dispersion (A3) in which the acid dye was dispersed was obtained.

[0210] (Preparation of colorant dispersion (A4)) · Basic dye: Basic Yellow 24 (manufactured by Alpha Chemicals): 70 parts · Anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 30 parts · Ion-exchanged water: 200 parts The above materials were mixed and dispersed for 10 minutes using a homogenizer (Ultra Turrax T50 manufactured by IKA). Ion-exchanged water was added so that the content of the basic dye in the dispersion was 20% by mass, and a colorant dispersion (A4) in which the basic dye was dispersed was obtained.

[0211] (Preparation of colorant dispersion (A5)) · Basic dye: Basic Yellow 1 (manufactured by Tokyo Chemical Industry Co., Ltd.): 70 parts · Anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 30 parts · Ion-exchanged water: 200 parts The above materials were mixed and dispersed for 10 minutes using a homogenizer (Ultra Turrax T50 manufactured by IKA). Ion-exchanged water was added so that the content of the basic dye in the dispersion was 20% by mass, and a colorant dispersion (A5) in which the basic dye was dispersed was obtained.

[0212] (Preparation of release agent particle dispersion (A1)) · Paraffin wax (HNP-9 manufactured by Nippon Seiro Co., Ltd.) 100 parts · Anionic surfactant (Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 1 part · Ion-exchanged water 350 parts The above materials were mixed, heated to 100 °C, dispersed using a homogenizer (Ultra Turrax T50 manufactured by IKA), and then dispersed using a Manton Gaulin high-pressure homogenizer (manufactured by Gaulin). A mold release agent particle dispersion (A1) (solid content: 20% by mass) in which mold release agent particles with a volume average particle diameter of 200 nm were dispersed was obtained.

[0213] <Preparation of Toner Particles A1> · Amorphous polyester resin particle dispersion (A1): 425 parts · Crystalline polyester resin particle dispersion (A1): 32 parts · Colorant dispersion (A1): 20 parts · Mold release agent dispersion (A1): 50 parts · Anionic surfactant (TaycaPower manufactured by Tayca Corporation): 30 parts The materials prepared above were placed in a round stainless steel flask, 0.1 N nitric acid was added to adjust the pH to 3.5, and then 30 parts of an aqueous nitric acid solution with a polyaluminum chloride concentration of 10% by mass was added. Subsequently, after dispersing at 30 °C using a homogenizer (Ultra Turrax T50 manufactured by IKA), it was heated to 40 °C in an oil bath for heating and held for 30 minutes. Then, 100 parts of an amorphous polyester resin particle dispersion (A1) was gently added as an additional dispersion and held for 1 hour. After adding 0.1 N aqueous sodium hydroxide solution to adjust the pH to 8.5, it was heated to 100 °C while continuing stirring and held for 10 hours. Then, the temperature inside the system was set to 53 °C (annealing treatment) and held for 1 hour. Then, it was cooled to room temperature. Then, it was filtered, thoroughly washed with ion-exchanged water, and dried to obtain toner particles with a volume average particle diameter of 6.0 μm. And the obtained toner particles were designated as toner particles (A1).

[0214] <Preparation of Toner Particles (A2) to (A45), (AC1), (AC2), and (AC4) to (AC8)> According to Tables 1 to 3, toner particles were obtained in the same manner as toner particles (A1), except that the type and amount of the charged amorphous polyester resin particle dispersion, the type and amount of the charged crystalline polyester resin particle dispersion, the type and amount of the charged colorant dispersion, the amount of the charged mold release agent dispersion, and the temperature and holding time of the annealing treatment were changed. In addition, the additional dispersion used was the same dispersion as the charged amorphous polyester resin particle dispersion after the change. Here, the amount of the charged amorphous polyester resin particle dispersion refers to the amount initially added as a charged material to a round stainless steel flask in the production of toner particles.

[0215] <Production of toner particles (AC3)> Toner particles (AC3) were produced by the kneading and pulverizing method. Specifically, 40 parts of an amorphous polyester resin (the amorphous polyester resin synthesized during the preparation of the aforementioned amorphous polyester resin particle dispersion (1)), 20 parts of a crystalline polyester resin (the crystalline polyester resin synthesized during the preparation of the aforementioned crystalline polyester resin particle dispersion (1)), 1.0 part of the basic dye Rhodamine B (manufactured by Nippon Kasei Co., Ltd., Basic Violet 10), and 9.0 parts of paraffin wax (HNP-9 manufactured by Nippon Seiro Co., Ltd.) as a mold release agent were added and kneaded with a pressure kneader. This kneaded product was coarsely pulverized to produce toner particles (AC3) having a volume average particle diameter of 6.0 μm.

[0216] <Production of toner particles (P1)> (Synthesis of crystalline polyester resin (P1)) Into a 5-liter flask equipped with a stirrer, a nitrogen inlet tube, a temperature sensor, and a rectification column, 80.9 parts of fumaric acid, 46.3 parts of 1,10-decanediol, and 1 part of titanium tetraethoxide were added to 100 parts of the above materials (fumaric acid and 1,10-decanediol). The reaction was carried out at 150 °C for 4 hours while removing the generated water, and then the temperature was raised to 180 °C over 6 hours under a nitrogen stream and reacted at 180 °C for 6 hours. Thereafter, the reaction was carried out under reduced pressure for 1 hour and cooled to obtain an unmodified crystalline polyester resin (P1).

[0217] (Synthesis of Amorphous Polyester Resin (P1)) Into a 5-liter flask equipped with a stirrer, a nitrogen inlet tube, a temperature sensor, and a rectifying column, 30 parts of isophthalic acid, 70 parts of fumaric acid, 5 mol parts of bisphenol A ethylene oxide adduct, and 95 parts of bisphenol A propylene oxide adduct were charged. It took 1 hour to raise the temperature to 220 °C, and 1 part of titanium tetraethoxide was added to 100 parts of the above materials (isophthalic acid, fumaric acid, bisphenol A ethylene oxide adduct, and bisphenol A propylene oxide adduct). While distilling off the generated water, it took 0.5 hour to raise the temperature to 230 °C, and after continuing the dehydration condensation reaction at this temperature for 1 hour, the reaction product was cooled. Then, 2 parts of isophorone diisocyanate were added to 1 part of this resin so that the ratio became 2:1, 5 parts of ethyl acetate were added and dissolved, and after reacting at 200 °C for 3 hours and then cooling, an amorphous polyester resin (P1) having an isocyanate group at the terminal was obtained.

[0218] (Preparation of Release Agent Particle Dispersion) 100 parts of paraffin wax (HNP-9 manufactured by Nippon Seiro Co., Ltd.), 1 part of an anionic surfactant (Neogen RK manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), and 350 parts of ion-exchanged water were mixed and heated to 100 °C, dispersed using a homogenizer (Ultra Turrax T50 manufactured by IKA), and then dispersed using a Manton Gaulin high-pressure homogenizer (manufactured by Gaulin). A release agent particle dispersion (solid content: 20% by mass) in which release agent particles having a volume average particle diameter of 200 nm were dispersed was obtained.

[0219] (Preparation of Masterbatch) 150 parts of amorphous polyester resin (P1), 3.0 parts of a basic dye (Rhodamine B (manufactured by Nippon Kasei, Basic Violet 10)), and 20 parts of ion-exchanged water were mixed using a Henschel mixer. The obtained mixture was pulverized to prepare a masterbatch.

[0220] (Preparation of Oil Phase (A) / Aqueous Phase) 107 parts of amorphous polyester resin (P1), 75 parts of release agent dispersion, 18 parts of masterbatch, and 73 parts of ethyl acetate were put in, and stirred with a homogenizer (Ultra Turrax T50 manufactured by IKA) to dissolve and disperse them to obtain an oil phase (A). Also, 990 parts of ion-exchanged water, 100 parts of an anionic surfactant, and 100 parts of ethyl acetate were mixed and stirred in another flask to obtain an aqueous phase.

[0221] (Emulsification and dispersion) To 450 parts of the oil phase (A), 100 parts of a solution in which crystalline polyester resin (P1) was dissolved in ethyl acetate (solid content concentration: 10%) and 3 parts of isophoronediamine were added, and stirred with a homogenizer (Ultra Turrax T50 manufactured by IKA) to dissolve, and dispersed at 50°C to obtain an oil phase (B). Next, 400 parts of the aqueous phase was put into another container and stirred at 50°C with a homogenizer (Ultra Turrax T50 manufactured by IKA). To this aqueous phase, 50 parts of the oil phase (B) was added, and stirred at 50°C for 5 minutes using a homogenizer (Ultra Turrax T50 manufactured by IKA) to obtain an emulsion slurry. This emulsion slurry was desolvated at 50°C for 15 hours to obtain a toner slurry. After subjecting the toner slurry to vacuum filtration, a washing treatment was performed to obtain toner particles.

[0222] Thereafter, after washing, a dispersion obtained by adding 50 parts of toner particles and 500 parts of ion-exchanged water was put into a 5-liter flask equipped with a stirring device, a nitrogen introduction tube, a temperature sensor, and a rectification column, stirred, and then heated up to 85°C. After the temperature rise, the dispersion was stirred for 24 hours while maintaining the temperature after the temperature rise. As a result, the toner particles were heated at 85°C for 24 hours. Thereafter, liquid nitrogen was introduced into the dispersion, and the toner particles were cooled (quenched) at 20°C / min to room temperature (25°C). Thereafter, it was reheated to 53°C and held for 1 hour. Thereafter, it was cooled to 20°C at a rate of 20°C / min.

[0223] (Drying and sieving) The obtained toner particles were dried and sieved to produce toner particles having a volume average particle diameter of 6.0 μm.

[0224] Through the above steps, toner particles (P1) were obtained.

[0225] <Examples 1 to 46, Comparative Examples 1 to 8> 100 parts of each of the obtained toner particles and 0.7 part of dimethyl silicone oil-treated silica particles (RY200 manufactured by Nippon Aerosil Co., Ltd.) were mixed with a Henschel mixer to obtain the toner of each example. Then, 8 parts of each of the obtained toners and 100 parts of the following carrier were mixed to obtain the developer of each example.

[0226] - Preparation of carrier - · 100 parts of ferrite particles (average particle diameter: 50 μm) · 14 parts of toluene · 3 parts of styrene / methyl methacrylate copolymer (copolymerization ratio: 15 / 85) · 0.2 part of carbon black The above components except for the ferrite particles were dispersed with a sand mill to prepare a dispersion. This dispersion was put into a vacuum degassing kneader together with the ferrite particles, and the pressure was reduced and dried while stirring to obtain the carrier.

[0227] <Evaluation> The developers obtained in each of the examples and comparative examples were respectively filled into the developing device of the image forming apparatus "DocuCentre color 400 manufactured by Fuji Xerox Co., Ltd.", and the following evaluations were performed using this image forming apparatus.

[0228] (Gloss difference evaluation) Under the environment of a temperature of 22°C and a humidity of 55%RH, 100 sheets of white paper images with an image density of 0% were output onto OS coated paper (manufactured by Oji Paper Co., Ltd., product name: OS Coat 127) at a process speed of 228 mm / s. Then, 100 sheets of solid images (toner loading amount (TMA 14.4 g / m 2 of the image) with an image density of 100% were output onto OS coated paper (manufactured by Oji Paper Co., Ltd., product name:) at a process speed of 228 mm / s. Regarding the first sheet of OS coated paper output and the 100th sheet of the Institute of Electronics and Communication Engineers test chart No. 5-1 output, the gloss of the green part was measured by the following method. The gloss was measured by using a portable gloss meter (BYK Gardner Micro Tri-Gloss, manufactured by Toyo Seiki Seisakusho Co., Ltd.), and the measurement of 60-degree gloss was carried out at five locations and averaged. The difference was obtained from the measured gloss values and evaluated according to the following evaluation criteria. A (◎): The maximum gloss difference between the first output image and the 2nd to 100th images is less than 2°. B (〇): The maximum gloss difference between the first output image and the 2nd to 100th images is 2° or more and less than 5°. C (×): The maximum gloss difference between the first output image and the 2nd to 100th images is 5° or more.

[0229] <Fixing Image Intensity Evaluation> The fixing image intensity evaluation was carried out as follows. On the color paper (J paper) manufactured by Fuji Xerox Co., Ltd., the toner loading amount was adjusted to 13.5 g / m 2 to form a solid image. After the toner image was output, using an external fixing machine, it was fixed at a nip width of 6.5 mm and a fixing speed of 180 mm / sec. However, the fixing temperature was fixed at 130°C to fix the toner image. A fold was made inside approximately at the center of the solid part of the fixing image on the paper, and the part where the fixing image was destroyed was wiped off with a tissue paper. The width of the white line was measured and evaluated according to the following evaluation criteria. A (◎): Those with a white line width of less than 0.5 mm B (〇): Those with a white line width of 0.5 mm or more and less than 1.0 mm C (×): Those with a white line width of 1.0 mm or more

[0230]

Table 1

[0231]

Table 2

[0232]

Table 3

[0233] The abbreviations in the table are as follows. · Surface ratio (%): The ratio of the crystalline resin, amorphous resin, or mold release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy · (Cry / Amo)×100: The ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy to the ratio of the amorphous resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy. · (Cry / Amo)×100: The ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy to the ratio of the mold release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy.

[0234] From the above results, it can be seen that the toner of this example can suppress the gloss difference that occurs when forming an image continuously.

Explanation of symbols

[0235] 1Y, 1M, 1C, 1K Photoconductor (an example of an image holding member) 2Y, 2M, 2C, 2K Charging roll (an example of a charging means) 3 Exposure device (an example of an electrostatic charge image forming means) 3Y, 3M, 3C, 3K Laser beam 4Y, 4M, 4C, 4K Developing device (an example of a developing means) 5Y, 5M, 5C, 5K Primary transfer roll (an example of a primary transfer means) 6Y, 6M, 6C, 6K Photoconductor cleaning device (an example of a cleaning means) 8Y, 8M, 8C, 8K Toner cartridge 10Y, 10M, 10C, 10K Image forming unit 20 Intermediate transfer belt (an example of an intermediate transfer member) 22 Driving roll 24 Support roll 26 Secondary transfer roll (an example of a secondary transfer means) 30 Intermediate transfer member cleaning device 107 Photoconductor (an example of an image holding member) 108 Charging roll (an example of charging means) 109 Exposure device (an example of electrostatic charge image forming means) 111 Developing device (an example of developing means) 112 Transfer device (an example of transfer means) 113 Photoconductor cleaning device (an example of cleaning means) 115 Fixing device (an example of fixing means) 116 Mounting rail 118 Opening for exposure 117 Housing 200 Process cartridge 300 Recording paper (an example of recording medium) P Recording paper (an example of recording medium)

Claims

1. It has toner particles containing a binder resin containing an amorphous resin and a crystalline resin, a dye, and a release agent, The ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 15% or less, The dye is a basic dye, The content of the crystalline resin with respect to the toner particles is 1% by mass or more and 12% by mass or less, The melting temperature Tm of the crystalline resin is 60°C or more and 80°C or less, An electrostatic charge image developing toner in which the glass transition temperature Tg of the amorphous resin is 45°C or more and 60°C or less.

2. The electrostatic charge image developing toner according to claim 1, wherein the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 1% or more and 8% or less.

3. The electrostatic charge image developing toner according to claim 2, wherein the ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 3% or more and 5% or less.

4. The electrostatic charge image developing toner according to any one of claims 1 to 3, wherein the basic dye is at least one selected from a rhodamine-based dye containing a cationic group and an azo-based dye containing a cationic group.

5. The content of the release agent with respect to the toner particles is 5.0% by mass or more and 10.0% by mass or less, The electrostatic charge image developing toner according to any one of claims 1 to 4, wherein the ratio of the release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 3% or more and 15% or less.

6. The electrostatic charge image developing toner according to any one of claims 1 to 5, wherein the binder resin contains a urea-modified polyester resin as the amorphous resin.

7. The electrostatic charge image developing toner according to any one of claims 1 to 6, wherein the content of the dye with respect to the content of the crystalline resin is 5% by mass or more and 40% by mass or less.

8. It has toner particles containing a binder resin containing an amorphous resin and a crystalline resin, a dye, and a release agent, The ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 20% or less with respect to the ratio of the amorphous resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy, The ratio of the crystalline resin on the surface of the toner particles measured by X-ray photoelectron spectroscopy is 200% or less with respect to the ratio of the release agent on the surface of the toner particles measured by X-ray photoelectron spectroscopy, The dye is a basic dye, The content of the crystalline resin with respect to the toner particles is 1% by mass or more and 12% by mass or less, the melting temperature Tm of the crystalline resin is 60°C or more and 80°C or less, and the glass transition temperature Tg of the amorphous resin is 45°C or more and 60°C or less. A toner for electrostatic charge image development.

9. It has toner particles containing an amorphous resin and a crystalline resin as a binder resin, a dye, and a release agent, when the endothermic amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g), and the endothermic amount based on the endothermic peak derived from the crystalline resin in the second heating process is Qc2 (J / g), the formula: 10 ≦ Qc1 / Qc2 is satisfied, the dye is a basic dye, the content of the crystalline resin with respect to the toner particles is 1% by mass or more and 12% by mass or less, the melting temperature Tm of the crystalline resin is 60°C or more and 80°C or less, and the glass transition temperature Tg of the amorphous resin is 45°C or more and 60°C or less. A toner for electrostatic charge image development.

10. It has toner particles containing an amorphous resin and a crystalline resin as a binder resin, a dye, and a release agent, when the endothermic amount based on the endothermic peak derived from the crystalline resin in the first heating process in differential scanning calorimetry is Qc1 (J / g), and the endothermic amount Qw1 (J / g) based on the endothermic peak derived from the release agent in the first heating process, the formula: 0.2 ≦ Qc1 / Qw1 is satisfied, the dye is a basic dye, the content of the crystalline resin with respect to the toner particles is 1% by mass or more and 12% by mass or less, the melting temperature Tm of the crystalline resin is 60°C or more and 80°C or less, and the glass transition temperature Tg of the amorphous resin is 45°C or more and 60°C or less. A toner for electrostatic charge image development.

11. An electrostatic charge image developer containing the toner for electrostatic charge image development according to any one of Claims 1 to 10.

12. A toner cartridge that houses the toner for electrostatic charge image development according to any one of Claims 1 to 10, and is detachable from an image forming apparatus.

13. A process cartridge that houses the electrostatic charge image developer according to Claim 11, and has developing means for developing an electrostatic charge image formed on the surface of an image carrier as a toner image with the electrostatic charge image developer, and is detachable from an image forming apparatus.

14. An image carrier, charging means for charging the surface of the image carrier, and electrostatic charge image forming means for forming an electrostatic charge image on the charged surface of the image carrier Developing means for accommodating the electrostatic charge image developer according to claim 11 and developing the electrostatic charge image formed on the surface of the image carrier as a toner image with the electrostatic charge image developer; Transfer means for transferring the toner image formed on the surface of the image carrier to the surface of a recording medium; Fixing means for fixing the toner image transferred to the surface of the recording medium; An image forming apparatus comprising the same.

15. The fixing means includes a fixing member and a pressing member that presses the outer peripheral surface of the fixing member and sandwiches the recording medium having an unfixed toner image formed on its surface together with the fixing member; The image forming apparatus according to claim 14, which does not have a coating mechanism for applying a release agent to the surface of the fixing member.

Images