JP7047527B2 - Toner for static charge image development, static charge image developer, toner cartridge, process cartridge, image forming method and image forming apparatus - Google Patents

Description

The present invention relates to a toner for static charge image development, an electrostatic latent image developer, a toner cartridge, a process cartridge, an image forming method, and an image forming apparatus.

Conventionally, a technique using a toner for developing an electrostatic charge image has been known in electrophotographic image formation.
Here, Patent Document 1 discloses "a toner for static charge image development containing toner particles containing at least a binder resin having a polyester resin and a styrene acrylic resin, a colorant, and a mold release agent". There is. Further, in Patent Document 1, the toner particles take a form in which a domain phase of a styrene acrylic resin and a domain phase of a mold release agent are dispersed in a matrix phase made of a polyester resin, and the domain phase of the styrene acrylic resin. It is also disclosed that and the domain phase of the release agent are adjacent to each other.

Further, Patent Document 2 describes "a hybrid polyester resin which is a graft copolymer in which a crystalline polyester resin unit which is a side chain is chemically bonded to an amorphous polyester resin unit which is a main chain and an amorphous polyester. "Toner for developing an electrostatic charge image containing a binder resin containing a resin" is disclosed. Further, Patent Document 2 also discloses that the binder resin has a phase-separated structure in which a dispersed phase of a hybrid polyester resin is dispersed in a continuous phase of the amorphous polyester resin.

Further, Patent Document 3 contains "a binder resin containing a hybrid crystalline resin having a structure in which a crystalline polyester resin unit and an amorphous polyester resin unit are chemically bonded, and a crystal nucleating agent. "Toner for developing an electrostatic latent image containing toner matrix particles" is disclosed.

Japanese Unexamined Patent Publication No. 2016-053677 Japanese Unexamined Patent Publication No. 2016-18396 Japanese Unexamined Patent Publication No. 2016-224367

Conventionally, a toner for static charge image development having toner particles containing a binder resin containing a hybrid resin in which a crystalline polyester resin unit and an amorphous polyester resin unit are chemically bonded and a vinyl-based resin, and a mold release agent. It is known that low temperature fixability can be obtained. However, in this static charge image developing toner, a phenomenon (hereinafter, also referred to as “cold offset”) occurs in which the static charge image developing toner is transferred to the fixing member because the fixing temperature is too low in a low temperature environment. There is.
Therefore, the present invention has toner particles containing a binder resin containing a hybrid resin chemically bonded to a crystalline polyester resin and an amorphous polyester resin and a vinyl-based resin, and a release agent, and is released from the mold. Compared with the case of a static charge image developing toner in which the domain of the hybrid resin is present in the region within 100 nm from the surface of the domain of the agent with an average area ratio of less than 10% or more than 20%, the toner has low temperature fixing property and a low temperature. An object of the present invention is to provide a toner for static charge image development that suppresses the occurrence of cold offset in an environment.

The above problem is solved by the following means.

<1> A binder resin containing a hybrid resin obtained by chemically bonding a crystalline polyester resin unit and an amorphous polyester resin unit, a vinyl resin, and the like.
Release agent and
Has toner particles containing
The toner particles have the domain of the release agent and the domain of the hybrid resin.
A toner for static charge image development in which the domain of the hybrid resin is present in a region within 100 nm from the surface of the domain of the mold release agent with an average area ratio of 10% or more and 20% or less.

<2> A binder resin containing a hybrid resin obtained by chemically bonding a crystalline polyester resin unit and an amorphous polyester resin unit, a vinyl resin, and the like.
Release agent and
Has toner particles containing
The toner particles have the domain of the release agent and the domain of the hybrid resin.
A toner for static charge image development in which domains of the hybrid resin are present in an average number of 2 or more and 7 or less in a region within 100 nm from the surface of the domain of the release agent.

<3> The toner for static charge image development according to <1> or <2>, wherein the vinyl resin is a styrene (meth) acrylic resin.

<4> The toner for static charge image development according to any one of <1> to <3>, wherein the average diameter of the domain of the release agent is 0.5 μm or more and less than 2 μm.

<5> The toner for static charge image development according to <4>, wherein the average diameter of the domain of the release agent is 0.6 μm or more and less than 1.5 μm.

<6> The ratio of the average diameter of the domain of the release agent to the average diameter of the domain of the hybrid resin is 1.2 / 0.5 or more and 1.1 / 0.1 or less. The toner for developing an electrostatic charge image according to any one of <5>.

<7> The ratio of the average area ratio of the domain of the mold release agent to the entire toner particles and the average area ratio of the domain of the hybrid resin to the entire toner particles is 10/50 or more and 30/17 or less. The toner for static charge image development according to any one of <1> to <6>.

<8> The ratio of the average number of domains of the release agent to the entire toner particles to the average number of domains of the hybrid resin to the entire toner particles is 16/50 or more and 20/25 or less. The toner for developing an electrostatic charge image according to any one of 1> to <7>.

<9> The toner for static charge image development according to any one of <1> to <8>, wherein the content of the release agent with respect to the toner particles is 3% by mass or more and less than 30% by mass.

<10> The toner for static charge image development according to any one of <1> to <9>, wherein the content of the hybrid resin with respect to the release agent is 200% by mass or more and 500% by mass or less.

<11> The toner for static charge image development according to any one of <1> to <10>, wherein the content of the hybrid resin with respect to the toner particles is 30% by mass or more and less than 50% by mass.

<12> The toner for static charge image development according to any one of <1> to <11>, wherein the difference between the melting temperature of the mold release agent and the melting temperature of the hybrid resin is 49 ° C. or less.

<13> The toner for static charge image development according to <12>, wherein the difference between the melting temperature of the mold release agent and the melting temperature of the hybrid resin is 35 ° C. or less.

<14> An electrostatic latent image developer containing the toner for static charge image development according to any one of <1> to <13>.

<15> The toner for static charge image development according to any one of <1> to <13> is accommodated.
A toner cartridge that is attached to and detached from the image forming device.

<16> A developing means for accommodating the electrostatic charge image developer according to <14> and developing the electrostatic charge image formed on the surface of the image holder as a toner image by the electrostatic charge image developer is provided.
A process cartridge that is attached to and detached from the image forming device.

<17> A charging process that charges the surface of the image holder,
A static charge image forming step of forming a static charge image on the surface of the charged image holder, and
A developing step of developing an electrostatic charge image formed on the surface of the image holder as a toner image by using the electrostatic charge image developer according to <14>.
A transfer step of transferring a toner image formed on the surface of the image holder to the surface of a recording medium, and
A fixing step of fixing the toner image transferred to the surface of the recording medium, and
Image forming method having.

<18> Image holder and
A charging means for charging the surface of the image holder, and
An electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image holder, and
A developing means for accommodating the electrostatic charge image developer according to <14> and developing the electrostatic charge image formed on the surface of the image holder as a toner image by the electrostatic image developer.
A transfer means for transferring a toner image formed on the surface of the image holder to the surface of a recording medium,
A fixing means for fixing the toner image transferred to the surface of the recording medium, and
An image forming apparatus.

According to the invention described in <1> or <3>, a binder resin containing a hybrid resin in which a crystalline polyester resin and an amorphous polyester resin are chemically bonded and a vinyl-based resin, and a release agent are contained. Compared with the case of a toner for static charge image development, which has toner particles to be used and the domain of the hybrid resin is present in a region within 100 nm from the surface of the domain of the release agent with an average area ratio of less than 10% or more than 20%. Provided is a toner for static charge image development that suppresses the occurrence of cold offset in a low temperature environment while having low temperature fixing property.

According to the invention described in <2> or <3>, a binder resin containing a hybrid resin in which a crystalline polyester resin and an amorphous polyester resin are chemically bonded and a vinyl-based resin, and a release agent are contained. The toner particles have the domain of the mold release agent and the domain of the hybrid resin in the toner particles, and the average number of domains of the hybrid resin is in the region within 100 nm from the surface of the domain of the mold release agent. Provided is a toner for static charge image development which suppresses the occurrence of cold offset in a low temperature environment while having low temperature fixing property as compared with the case where the toner is present for less than 2 or more than 7 for static charge image development. Will be done.

According to the invention described in <4> or <5>, as compared with the case where the average diameter of the domain of the release agent is less than 0.5 μm or 2 μm or more, it has low temperature fixability and is in a low temperature environment. Toner for static charge image development that suppresses the occurrence of cold offset is provided.

According to the invention described in <6>, the ratio of the average diameter of the domain of the release agent to the average diameter of the domain of the hybrid resin is less than 1.2 / 0.5 or 1.1 / 0.1. Provided is a static charge image developing toner that suppresses the occurrence of cold offset in a low temperature environment while having low temperature fixing property as compared with the case where the temperature exceeds the limit.

According to the invention described in <7>, the ratio of the average area ratio of the domain of the mold release agent to the entire toner particles and the average area ratio of the domain of the hybrid resin to the entire toner particles is 10/50. Provided is a toner for static charge image development that suppresses the occurrence of cold offset in a low temperature environment while having low temperature fixing property as compared with the case where the amount is less than or more than 30/17.

According to the invention described in <8>, the ratio of the average number of domains of the mold release agent to the entire toner particles to the average number of domains of the hybrid resin to the entire toner particles is less than 16/50 or Provided is a toner for static charge image development that suppresses the occurrence of cold offset in a low temperature environment while having low temperature fixing property as compared with the case of exceeding 20/25.

According to the invention described in <9>, as compared with the case where the content of the release agent in the toner particles is less than 3% by mass or 30% by mass or more, the toner particles have low temperature fixability and are in a low temperature environment. Toner for developing a static charge image that suppresses the occurrence of cold offset in the above is provided.

According to the invention described in <10>, as compared with the case where the content of the hybrid resin with respect to the mold release agent is less than 200% by mass or more than 500% by mass, it has low temperature fixability and is in a low temperature environment. Toner for developing a static charge image that suppresses the occurrence of cold offset in the above is provided.

According to the invention described in <11>, as compared with the case where the content of the hybrid resin with respect to the toner particles is less than 30% by mass or 50% by mass or more, the toner particles have low-temperature fixability and are in a low-temperature environment. Toner for static charge image development that suppresses the occurrence of cold offset is provided.

According to the invention described in <12> or <13>, the difference between the melting temperature of the mold release agent and the melting temperature of the hybrid resin is more than 49 ° C., while having low temperature fixing property. A toner for static charge image development that suppresses the occurrence of cold offset in a low temperature environment is provided.

According to the invention according to <14>, <15>, <16>, <17> or <18>, a hybrid resin obtained by chemically bonding a crystalline polyester resin and an amorphous polyester resin and a vinyl resin are included. It has toner particles containing a binder resin and a release agent, and the domain of the hybrid resin is present in a region within 100 nm from the surface of the domain of the release agent with an average area ratio of less than 10% or more than 20%. A static charge image developer, a toner cartridge, a process cartridge, an image forming method, or an image forming agent that suppresses the occurrence of cold offset in a low temperature environment while having low temperature fixing property as compared with the case of a toner for static charge image developing. Equipment is provided.

It is a schematic diagram which shows an example of the cross section of the toner particle which concerns on this embodiment. It is a schematic diagram which shows an example of the relationship between the domain of a mold release agent and the domain of a hybrid resin existing in the region within 100 nm from the surface of the domain of a mold release agent in the cross section of the toner particle which concerns on this embodiment. It is a schematic block diagram which shows an example of the image forming apparatus which concerns on this embodiment. It is a schematic block diagram which shows an example of the process cartridge which concerns on this embodiment.

Hereinafter, embodiments that are an example of the present invention will be described.
In the present embodiment, the amount of each component in the object is such that when a plurality of substances corresponding to each component are present in the object, the plurality of substances existing in the object are present unless otherwise specified. Means the total content or content of.

-Toner for static charge image development-
The static charge image developing toner (hereinafter, also simply referred to as “toner”) according to the first embodiment is a hybrid resin (hereinafter, simply “hybrid resin”) in which a crystalline polyester resin unit and an amorphous polyester resin unit are chemically bonded. It also has toner particles containing a binder resin containing a vinyl resin and a mold release agent, and has a domain of the mold release agent and a domain of the hybrid resin in the toner particles. The domain of the hybrid resin is present in a region within 100 nm from the surface of the domain of the release agent with an average area ratio of 10% or more and 20% or less.

Conventionally, it is known that low temperature fixability can be obtained by using a toner having toner particles containing a binder resin containing a hybrid resin and a vinyl resin and a mold release agent. However, when an image is formed using the toner particles having the above configuration in a low temperature environment, the temperature of the fixing member at the initial stage of image formation may not reach the target temperature. Therefore, cold offset tends to occur in a low temperature environment. The cause of this cold offset is not always clear, but it can be considered as follows.
In the toner having the above structure, the affinity between the hybrid resin and the mold release agent tends to be high. Therefore, it is considered that the domain made of the hybrid resin is unevenly distributed so as to surround the surface of the domain made of the release agent. If the domain of the hybrid resin is unevenly distributed on the surface of the domain of the release agent, it is considered that the exudation of the release agent onto the surface of the toner particles is insufficient. Insufficient exudation of the release agent onto the surface of the toner particles tends to reduce the releasability of the toner particles. In particular, when the releasability of the toner particles is low in a low temperature environment, the temperature of the fixing member at the initial stage of image formation does not reach the target temperature when forming an image using the toner particles. Cold offset is considered to occur.

On the other hand, the toner according to the first embodiment forms, for example, a continuous phase of a vinyl resin, a domain of a hybrid resin, and a domain of a mold release agent in the toner particles, as shown in FIG. The domain of the hybrid resin is present in a region within 100 nm from the surface of the domain of the release agent with an average area ratio of 10% or more and 20% or less. That is, the domain of the hybrid resin is not unevenly distributed on the surface of the domain of the release agent, but is dispersed over the entire toner particles. By dispersing the hybrid resin over the entire toner particles, the releasability of the toner particles tends to be improved. As a result, it is considered that a toner that suppresses the occurrence of cold offset in a low temperature environment while having low temperature fixing property is provided. In FIG. 1, 700 is a toner particle, 600 is a domain of a hybrid resin, 500 is a domain of a mold release agent, and 400 is a continuous phase of a vinyl resin.

Further, in the toner according to the second embodiment, toner particles containing a binder resin containing a hybrid resin in which a crystalline polyester resin unit and an amorphous polyester resin unit are chemically bonded and a vinyl resin, and a mold release agent are contained. The toner particles have a release agent domain and a hybrid resin domain, and the average number of hybrid resin domains is 2 or more and 7 or less in a region within 100 nm from the surface of the release agent domain. ..

As described above, conventional toner tends to have a high affinity between the hybrid resin and the release agent. Therefore, it is considered that the domain made of the hybrid resin is unevenly distributed so as to surround the surface of the domain made of the release agent. More specifically, a large number of hybrid resin domains tend to be unevenly distributed (for example, hybrid resins having an average number of 7 or more are unevenly distributed) in a region within 100 nm from the surface of the release agent domain. If the domain of the hybrid resin is unevenly distributed on the surface of the domain of the release agent, it is considered that the exudation of the release agent onto the surface of the toner particles is insufficient. As a result, it is considered that the releasability of the toner particles is lowered and cold offset occurs in a low temperature environment.

In the toner according to the second embodiment, the number of domains of the hybrid resin is 2 or more and 7 or less on average in the region within 100 nm from the surface of the domain of the release agent. That is, the hybrid resin is dispersed in the entire toner particles without being unevenly distributed within 100 nm from the surface of the release agent domain. By dispersing the hybrid resin over the entire toner particles, the releasability of the toner particles tends to be improved as in the case of the toner according to the first embodiment. As a result, it is considered that a toner that suppresses the occurrence of cold offset in a low temperature environment while having low temperature fixing property is provided.

Hereinafter, the configurations of the toner according to the first and second embodiments (hereinafter collectively referred to as “the present embodiment” for convenience) will be described in detail. The reference numerals will be omitted.

The toner according to the present embodiment is composed of toner particles and, if necessary, an external additive.

-Toner particles-
Hereinafter, the toner particles will be described.
The toner particles contain a binder resin containing a hybrid resin and a vinyl resin, and a mold release agent. The toner particles according to this embodiment may be composed of other components.

[Characteristics of toner particles]
Hereinafter, the characteristics of the toner particles will be described.

The toner particles have a domain of the release agent and a domain of the hybrid resin. For example, as shown in FIG. 2, the domain of the hybrid resin has an average area ratio of 10 in a region within 100 nm from the surface of the domain of the release agent. It exists in% or more and 20% or less.

Further, in the toner particles, the number of domains of the hybrid resin is 2 or more and 7 or less on average in the region within 100 nm from the surface of the domain of the release agent.

As a control method in which the average area ratio and the average number of the domains of the hybrid resin existing in the region within 100 nm from the surface of the domain of the release agent are within the above ranges, for example, in the aggregation step in the production of toner particles described later. Examples thereof include a method of adding the hybrid resin particle dispersion in a stepwise manner, a method of adjusting the content of the hybrid resin contained in the hybrid resin particle dispersion, and the like.

(Average area ratio of each domain)
The average area ratio of the domain of the hybrid resin present in the region within 100 nm from the surface of the domain of the release agent is 10% or more and 20% or less, preferably 12% or more and 18% or less, and more preferably 13%. More than 18% or less.

When the average area ratio of the domain of the hybrid resin existing in the region within 100 nm from the surface of the domain of the release agent is 10% or more, the toner has low temperature fixability. On the other hand, when the average area ratio of the domain of the hybrid resin is 20% or less, the occurrence of cold offset in a low temperature environment is suppressed.

The average area ratio of the release agent domain to the entire toner particles is preferably 5% or more and 30% or less, more preferably 5% or more and 20% or less, and 5% or more and 15% or less. More preferred.

The average area ratio of the domain of the hybrid resin to the entire toner particles is preferably 30% or more and 60 or less, more preferably 30% or more and 50% or less, and further preferably 40% or more and 50% or less. ..

The ratio of the average area ratio of the release agent domain to the entire toner particles to the average area ratio of the hybrid resin domain to the entire toner particles (average area ratio of the release agent domain to the entire toner particles / hybrid to the entire toner particles). The average area ratio of the resin domain) is preferably 10/50 or more and 30/17 or less, preferably 10/50 or more and 12 or more, from the viewpoint of suppressing the occurrence of cold offset in a low temperature environment while having low temperature fixability. It is more preferably / 16 or less, and further preferably 10/50 or more and 10/14 or less.

(Average diameter of each domain)
The average diameter of the domain of the release agent is preferably 0.5 μm or more and less than 2 μm, preferably 0.6 μm or more and 1.8 μm, from the viewpoint of suppressing the occurrence of cold offset in a low temperature environment while maintaining low temperature fixability. It is more preferably less than, and further preferably 0.6 μm or more and less than 1.5 μm.

The average diameter of the domain of the hybrid resin is preferably 0.08 μm or more and less than 0.6 μm, more preferably 0.1 μm or more and less than 0.5 μm, and more preferably 0.1 μm or more and less than 0.4 μm. More preferred.

The ratio of the average diameter of the release agent domain to the average diameter of the domain of the hybrid resin (the ratio of the average diameter of the release agent domain / the average diameter of the hybrid resin domain) is in a low temperature environment while having low temperature fixability. From the viewpoint of suppressing the occurrence of cold offset in the above, it is preferably 1.2 / 0.5 or more and 1.1 / 0.1 or less, and 1.2 / 0.4 or more and 1.1 / 0.1 or less. It is more preferably 1.2 / 0.4 or more and 1.1 / 0.15 or less.

The average diameter of the release agent domain is, for example, the volume average particle diameter of the release agent particles contained in the release agent particle dispersion liquid in which the toner particles are manufactured by the aggregation and coalescence method. To adjust; Prepare multiple release agent particle dispersions with different volume average particle diameters and use them in combination; Adjust the temperature rise rate in the aggregate particle formation step and the solid content of each dispersion; Fusion -It can be controlled by adjusting the temperature (quenching conditions, etc.) in the union step; adjusting the amount of the surfactant; etc. Further, the average diameter of the domain of the hybrid resin can be controlled by the same method.

(Average number of each domain)
The average number of domains of the hybrid resin present in the region within 100 nm from the surface of the domain of the release agent is 2 or more and 7 or less, preferably 3 or more and 7 or less.

When the average number of domains of the hybrid resin present in the region within 100 nm from the surface of the domain of the release agent is 2 or more, the toner has low temperature fixability. On the other hand, when the average number of domains of the hybrid resin is 7 or less, the occurrence of cold offset in a low temperature environment is suppressed.

The average number of mold release agent domains with respect to the entire toner particles is preferably 8 or more and 30 or less, preferably 10 or more and 25 or less, from the viewpoint of suppressing the occurrence of cold offset in a low temperature environment while maintaining low temperature fixability. It is more preferable that there is, and it is further preferable that it is 10 or more and 20 or less.

The average number of domains of the hybrid resin with respect to the entire toner particles is preferably 20 or more and 100 or less, preferably 25 or more and 80 or less, from the viewpoint of suppressing the occurrence of cold offset in a low temperature environment while maintaining low temperature fixability. More preferably, it is more preferably 30 or more and 75 or less.

Ratio of the average number of mold release agent domains to the entire toner particles to the average number of hybrid resin domains to the entire toner particles (average number of mold release agent domains to the entire toner particles / hybrid resin domains to the entire toner particles) The average number of particles) is preferably 16/50 or more and 20/25 or less, and 16/50 or more and 20/30 or less, from the viewpoint of suppressing the occurrence of cold release in a low temperature environment while maintaining low temperature fixability. More preferably, it is more preferably 16/50 or more and 18/40 or less.

Hereinafter, the measuring method regarding the average area ratio of each domain, the ratio of the average area ratio, the domain diameter, the ratio of the domain diameter, the average number and the ratio of the average number will be described.
Toner is mixed with epoxy resin and embedded to solidify the epoxy resin. Then, the obtained solidified product is cut by an ultramicrotome device (UltracutUCT, manufactured by Leica) to prepare a flaky sample having a thickness of 80 nm or more and 130 nm or less. Next, the obtained flaky sample is stained with osmium tetroxide in a desiccator at 30 ° C. for 3 hours. Then, an SEM image of the stained flaky sample is obtained with an ultra-high resolution field emission scanning electron microscope (SEM: S-4800, manufactured by Hitachi High-Technologies, Inc.). Here, since the hybrid resin, the vinyl-based resin, and the release agent are likely to be stained with osmium tetroxide in this order, each component is identified by the shade depending on the degree of staining. If it is difficult to distinguish the shade due to the condition of the sample, adjust the staining time.

The average area ratio of the domain of the hybrid resin existing in the region within 100 nm from the surface of the domain of the release agent (hereinafter, also referred to as “the domain of the specific hybrid resin”) is determined by the following method.
(1) In the SEM image, a toner particle cross section having a maximum length of 85% or more of the volume average particle diameter of the toner particles is selected, and the stained release agent domain is observed.
(2) Obtain the area of the region within 100 nm from the surface of the domain of the selected mold release agent. At this time, the area means the area of the region obtained by subtracting the area of the release agent domain itself from the area of the region surrounded by the region line 100 nm away from the surface of the release agent domain.
(3) Obtain the area of the domain of the specific hybrid resin. When the domain of the hybrid resin is present on the boundary line of the region within 100 nm from the surface of the domain of one release agent, the hybrid resin overlapping within the region within 100 nm from the surface of the domain of the release agent. A part of the domain area is defined as the domain area of the specific hybrid resin.
(4) Area ratio (%) of the domain of the specific hybrid resin = (area of the domain of the specific hybrid resin / area of the region within 100 nm from the surface of the domain of the release agent) × 100 is obtained.
(5) The above methods (1) to (4) are performed for 100 mold release agent domains in a plurality of toner particles, and the arithmetic mean value thereof is defined as the average area ratio.

If the region within 100 nm from the surface of the domain of one release agent and the region within 100 nm from the surface of the domain of another release agent overlap each other, the domain of the specific hybrid resin is used. The average area ratio is calculated for each mold release agent domain.

The average area ratio of the release agent domain to the entire toner particles is determined by the following method.
(1) In the SEM image, a toner particle cross section having a maximum length of 85% or more of the volume average particle diameter of the toner particles is selected, and the stained release agent domain is observed.
(2) Obtain the area of the selected toner particle cross section.
(3) Obtain the area of the domain of all the release agents observed in the cross section of the toner particles.
(4) Area ratio (%) of mold release agent domain to the entire toner particles = (area of all mold release agent domains observed in the toner particle cross section / area of the toner particle cross section) × 100 is obtained.
(5) The above methods (1) to (4) are performed on 100 toner particles, and the arithmetic mean value thereof is taken as the average area ratio.

The average area ratio of the hybrid resin domain to the entire toner particles is obtained by the following method.
(1) In the SEM image, a toner particle cross section having a maximum length of 85% or more of the volume average particle diameter of the toner particles is selected, and the domain of the dyed hybrid resin is observed.
(2) Obtain the area of the selected toner particle cross section.
(3) Obtain the area of the domain of all the hybrid resins observed in the cross section of the toner particles.
(4) Area ratio (%) of the hybrid resin to the entire toner particles = (area of all hybrid resin domains observed in the cross section of the toner particles / area of the cross section of the toner particles) × 100 is obtained.
(5) The above methods (1) to (4) are performed on 100 toner particles, and the arithmetic mean value thereof is taken as the average area ratio.

The ratio of the average area ratio of the release agent domain to the entire toner particles and the average area ratio of the hybrid resin domain to the entire toner particles is determined by the following method.
(1) In the SEM image, a toner particle cross section having a maximum length of 85% or more of the volume average particle diameter of the toner particles is selected, and the stained mold release agent domain and hybrid resin domain are observed.
(2) The average area ratio of the release agent domain to the entire toner particles is obtained by the above-mentioned method.
(3) The average area ratio of the domain of the hybrid resin to the entire toner particles is obtained by the above-mentioned method.
(4) Ratio of the average area ratio of the release agent domain to the entire toner particles to the average area ratio of the hybrid resin domain to the entire toner particles (average area ratio of the release agent domain to the entire toner particles / toner particles) Calculate the average area ratio of the domain of the hybrid resin to the whole).

The average diameter of the release agent domain is determined by the following method. The average diameter of the domain of the hybrid resin is also obtained in the same manner as the average diameter of the domain of the release agent.
(1) In the SEM image, a toner particle cross section having a maximum length of 85% or more of the volume average particle diameter of the toner particles is selected, and the stained release agent domain is observed.
(2) From the area of the mold release agent obtained in the SEM image, the diameter of a circle having the same area is calculated as the equivalent circle diameter.
(3) The above methods (1) and (2) are performed for 100 mold release agent domains in a plurality of toner particles, and the arithmetic mean value of each circle equivalent diameter is used as the average diameter.

The ratio of the average diameter of the release agent domain to the average diameter of the domain of the hybrid resin is determined by the following method.
(1) In the SEM image, a toner particle cross section having a maximum length of 85% or more of the volume average particle diameter of the toner particles is selected, and the stained mold release agent domain and hybrid resin domain are observed.
(2) The average diameter of the domain of the release agent is obtained by the above-mentioned method.
(3) The average diameter of the domain of the hybrid resin is obtained by the above-mentioned method.
(4) The ratio of the average diameter of the release agent domain to the average diameter of the domain of the hybrid resin (the ratio of the average diameter of the release agent domain / the average diameter of the hybrid resin domain) is obtained.

The average number of domains of the specific hybrid resin is obtained by the following method.
(1) In the SEM image, a toner particle cross section having a maximum length of 85% or more of the volume average particle diameter of the toner particles is selected, and the stained release agent domain is observed.
(2) Count the number of hybrid resin domains existing in the region within 100 nm from the surface of the selected mold release agent domain. When the domain of the hybrid resin is present on the boundary line of the region within 100 nm from the surface of the domain of one mold release agent, the domain of the hybrid resin existing on the boundary line of the region is referred to as the specific hybrid resin. Count as a domain.
(3) The above methods (1) and (2) are performed on 100 toner particles, and the arithmetic mean value thereof is taken as the average number.

The average number of hybrid resin domains with respect to the entire toner particles is determined by the following method. The average number of mold release agent domains for the entire toner particles is also determined in the same manner as the average number of hybrid resins.
(1) In the SEM image, select a toner particle cross section having a maximum length of 85% or more of the volume average particle diameter of the toner particles.
(2) Count the number of domains of all hybrid resins observed in the cross section of the toner particles.
(3) The above methods (1) and (2) are performed on 100 toner particles, and the arithmetic mean value thereof is taken as the average number.

The ratio of the average number of mold release agent domains to the entire toner particles and the average number of hybrid resin domains to the entire toner particles is determined by the following method.
(1) In the SEM image, a toner particle cross section having a maximum length of 85% or more of the volume average particle diameter of the toner particles is selected, and the stained mold release agent domain and hybrid resin domain are observed.
(2) By the above-mentioned method, the average number of domains of the release agent with respect to the entire toner particles is obtained.
(3) By the above-mentioned method, the average number of domains of the hybrid resin with respect to the entire toner particles is obtained.
(4) Ratio of the average number of mold release agent domains to the entire toner particles to the average number of hybrid resin domains to the entire toner particles (average number of mold release agent domains to the entire toner particles / hybrid to the entire toner particles) Calculate the average number of resin domains).

The volume average particle diameter D50v of the toner particles is preferably 2.0 μm or more and 6.0 μm or less, more preferably 3.0 μm or more and 5.0 μm or less, and 3.5 μm or more and 4.0 μm or less. Is more preferable.

The average particle size of the toner particles is measured using Coulter Multisizer II (manufactured by Beckman Coulter), and the electrolytic solution is measured using ISOTON-II (manufactured by Beckman Coulter).
At the time of measurement, 0.5 mg or more and 50 mg or less of the measurement sample is added to 2 ml of a 5% aqueous solution of a surfactant (preferably sodium alkylbenzene sulfonate) as a dispersant. This is added to 100 ml or more and 150 ml or less of the electrolytic solution.
The electrolytic solution in which the sample is suspended is dispersed for 1 minute with an ultrasonic disperser, 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 obtained by using an aperture with an aperture diameter of 100 μm by the Coulter Multisizer II. taking measurement. The number of particles to be sampled is 50,000.
A cumulative distribution is drawn from the small diameter side for the volume divided with respect to the particle size range (channel) divided based on the measured particle size distribution, and the particle size having a cumulative total of 50% is defined as the volume average particle size D50v.

The average circularity of the toner particles is preferably 0.94 or more and 1.00 or less, and more preferably 0.95 or more and 0.98 or less.

The average circularity of the toner particles is obtained by (circumferential peripheral length) / (peripheral length) [(circumferential length of a circle having the same projected area as the particle image) / (peripheral length of the particle projected image)]. Specifically, it is a value measured by the following method.
First, a flow-type particle image analyzer (Sysmex) that captures a particle image as a still image by sucking and collecting toner particles to be measured, forming a flat flow, and instantly emitting strobe light, and analyzing the particle image. Obtained by FPIA-3000) manufactured by the company. The number of samplings for obtaining the average circularity is set to 3500.
When the toner has an external additive, the toner (developer) to be measured is dispersed in water containing a surfactant, and then ultrasonic treatment is performed to obtain toner particles from which the external additive has been removed. ..

[Bundling resin]
Hereinafter, the binder resin will be described.
The binder resin includes a hybrid resin in which a crystalline polyester resin unit and an amorphous polyester resin unit are chemically bonded, and a vinyl-based resin. The binder resin may be composed of other binder resins.

(Hybrid resin)
Hereinafter, the hybrid resin will be described.
The binder resin of the present embodiment includes a hybrid resin.

The hybrid resin is a resin obtained by chemically bonding a crystalline polyester resin unit and an amorphous polyester resin unit.

The crystalline polyester resin unit refers to a resin portion having a structure derived from the crystalline polyester resin. Further, the amorphous polyester resin unit refers to a resin portion having a structure derived from an amorphous polyester resin.

Hereinafter, (A) a crystalline polyester resin unit and (B) an amorphous polyester resin unit will be described.

(A) Crystalline polyester resin unit As the crystalline polyester resin (hereinafter, also simply referred to as “crystalline polyester resin”) forming the crystalline polyester resin unit, for example, polycondensation of a polyvalent carboxylic acid and a polyhydric alcohol. The body is mentioned. As the crystalline polyester resin, a commercially available product may be used, or a synthetic resin may be used.
Here, since the crystalline polyester resin easily forms a crystal structure, a polycondensate using a polymerizable monomer having a linear aliphatic is preferable to a polymerizable monomer having an aromatic.

Examples of the polyvalent carboxylic acid include aliphatic dicarboxylic acids (eg, oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonandicarboxylic acid, 1,10-decandicarboxylic acid). Acids, 1,12-dodecanedicarboxylic acids, 1,14-tetradecanedicarboxylic acids, 1,18-octadecanedicarboxylic acids, etc.), aromatic dicarboxylic acids (eg, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid) Examples thereof include dibasic acids such as acids), these anhydrides, or lower (for example, 1 to 5 carbon atoms) alkyl esters thereof.
As the polyvalent carboxylic acid, a trivalent or higher carboxylic acid having 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 (for example, 1,2,3-benzenetricarboxylic acid, 1,2,4-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, etc.). Examples thereof include anhydrides or lower (for example, 1 to 5 carbon atoms) alkyl esters thereof.
As the polyvalent carboxylic acid, a dicarboxylic acid having a sulfonic acid group and 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.

Examples of the polyhydric alcohol include an aliphatic diol (for example, a linear aliphatic diol having 7 or more and 20 or less 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, and 1,8-. Octadecanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18- Examples thereof include octadecanediol and 1,14-eicosanedecanediol. Among these, as the aliphatic diol, 1,8-octanediol, 1,9-nonanediol and 1,10-decanediol are preferable.
As the polyhydric alcohol, a trihydric or higher alcohol having a crosslinked structure or a branched structure may be used in combination with the diol. Examples of the trihydric or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and the like.
The polyhydric alcohol may be used alone or in combination of two or more.

Here, the polyhydric alcohol often has an aliphatic diol content of 80 mol% or more, preferably 90 mol% or more.

The melting temperature of the crystalline polyester resin is preferably 50 ° C. or higher and 100 ° C. or lower, more preferably 55 ° C. or higher and 90 ° C. or lower, and further preferably 60 ° C. or higher and 85 ° C. or lower.
The melting temperature is obtained from the DSC curve obtained by differential scanning calorimetry (DSC) by the "melting peak temperature" described in the method for obtaining the melting temperature in JIS K7121-1987 "Method for measuring the transition temperature of plastics".

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

The crystalline polyester resin can be obtained by a well-known manufacturing method, for example, like the amorphous polyester described later.

(B) Atypical polyester resin unit Examples of the amorphous polyester resin (hereinafter, also simply referred to as “acrystalline polyester resin”) forming the amorphous polyester resin unit include a polyvalent carboxylic acid and a polyhydric alcohol. Examples thereof include a condensed polymer of. As the amorphous polyester resin, a commercially available product may be used, or a synthetic resin may be used.

Examples of the polyvalent carboxylic acid include aliphatic dicarboxylic acids (eg, 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 acid (eg cyclohexanedicarboxylic acid, etc.), aromatic dicarboxylic acid (eg, terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, etc.), these anhydrides, or their lower grades (eg, 1 or more carbon atoms). 5 or less) Alkyl ester can be mentioned. Among these, as the polyvalent carboxylic acid, for example, an aromatic dicarboxylic acid is preferable.
As the polyvalent carboxylic acid, a trivalent or higher carboxylic acid having a crosslinked structure or a branched structure may be used in combination with the dicarboxylic acid. Examples of the trivalent or higher carboxylic acid include trimellitic acid, pyromellitic acid, anhydrides thereof, and lower (for example, 1 to 5 carbon atoms) alkyl esters thereof.
The polyvalent carboxylic acid may be used alone or in combination of two or more.

Examples of the polyhydric alcohol include aliphatic diols (eg ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, etc.), alicyclic diols (eg, cyclohexanediol, cyclohexanedimethanol, etc.). Hydrogenated bisphenol A, etc.), aromatic diols (for example, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, etc.) can be mentioned. 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 trihydric or higher polyhydric alcohol having a crosslinked structure or a branched structure may be used in combination with the diol. Examples of the trihydric or higher polyhydric alcohol include glycerin, trimethylolpropane, and pentaerythritol.
The polyhydric alcohol may be used alone or in combination of two or more.

The glass transition temperature (Tg) of the amorphous polyester resin is preferably 50 ° C. or higher and 80 ° C. or lower, and more preferably 50 ° C. or higher and 65 ° C. or lower.
The glass transition temperature is obtained from the DSC curve obtained by differential scanning calorimetry (DSC), and more specifically described in JIS K 7121-1987 "Method for measuring the glass transition temperature". It is obtained by the "extra glass transition start temperature" of.

The weight average molecular weight (Mw) of the amorphous polyester resin is preferably 5,000 or more and 1,000,000 or less, and more preferably 7,000 or more and 500,000 or less.
The number average molecular weight (Mn) of the amorphous polyester resin is preferably 2000 or more and 100,000 or less.
The molecular weight distribution (Mw / Mn) of the amorphous polyester resin is preferably 1.5 or more and 100 or less, and 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 by using Tosoh's GPC / HLC-8120GPC as a measuring device, using Tosoh's column / TSKgel SuperHM-M (15 cm), and using a THF solvent. The weight average molecular weight and the number average molecular weight are calculated from this measurement result using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample.

The amorphous polyester resin is obtained by a well-known manufacturing method. Specifically, for example, it can be obtained by a method in which the polymerization temperature is 180 ° C. or higher and 230 ° C. or lower, the pressure inside the reaction system is reduced as necessary, and the reaction is carried out while removing water and alcohol generated during condensation.
When the raw material monomer is not dissolved or compatible at the reaction temperature, a solvent having a high boiling point may be added as a dissolution aid to dissolve the monomer. In this case, the polycondensation reaction is carried out while distilling off the dissolution aid. If a monomer with poor compatibility is present in the copolymerization reaction, the monomer with poor compatibility, the monomer, and the acid or alcohol to be polycondensed are condensed in advance, and then weighted together with the main component. It is good to condense.

(Hybrid resin synthesis method)
The hybrid resin is not particularly limited as long as it is a polymer having a structure in which a crystalline polyester resin unit and an amorphous polyester resin unit are chemically bonded, and a commercially available product may be used or a synthesized one may be used. You may. Specific examples of the method for synthesizing the hybrid resin include the methods shown below.

(1) A method in which an amorphous polyester resin unit is polymerized in advance and a polymerization reaction for forming a crystalline polyester resin unit is carried out in the presence of the amorphous polyester resin unit to synthesize a hybrid resin. , The monomer constituting the above-mentioned amorphous polyester resin unit is polymerized to form the amorphous polyester resin unit. Next, in the presence of the amorphous polyester resin unit, the polyvalent carboxylic acid and the polyhydric alcohol are polymerized to form a crystalline polyester resin unit. At this time, a hybrid resin is synthesized by subjecting the polyhydric carboxylic acid and the polyhydric alcohol to a condensation reaction and subjecting the amorphous polyester resin unit to an addition reaction of the polyvalent carboxylic acid or the polyhydric alcohol.

In the above method, it is preferable that the crystalline polyester resin unit or the amorphous polyester resin unit has a portion where these units react with each other. Specifically, when the amorphous polyester resin unit is formed, in addition to the monomer constituting the amorphous polyester resin unit, a site that reacts with a carboxy group or a hydroxyl group remaining in the crystalline polyester resin unit and a site. It is also possible to use a compound having a site that reacts with the amorphous polyester resin unit. That is, when this compound reacts with the carboxy group or the hydroxyl group in the crystalline polyester resin unit, the crystalline polyester resin unit can be chemically bonded to the amorphous polyester resin unit.

By using the above method, it is possible to synthesize a hybrid resin having a structure (graft structure) in which a crystalline polyester resin unit is chemically bonded to an amorphous polyester resin unit.

(2) A method of forming a crystalline polyester resin unit and an amorphous polyester resin unit, respectively, and combining them to synthesize a hybrid resin. In this method, first, a polyvalent carboxylic acid and a polyhydric alcohol are mixed. A crystalline polyester resin unit is formed by a condensation reaction. Further, apart from the reaction system for forming the crystalline polyester resin unit, the monomer constituting the above-mentioned amorphous polyester resin unit is polymerized to form the amorphous polyester resin unit. At this time, it is preferable that the crystalline polyester resin unit and the amorphous polyester resin unit have a portion where they react with each other. As a method of incorporating a site where both units react with each other, the same method as the above-mentioned method (1) may be used.

Next, by reacting the crystalline polyester unit formed above with the amorphous polyester resin unit, a hybrid resin having a structure in which the crystalline polyester resin unit and the amorphous polyester resin unit are chemically bonded is synthesized. ..

When the crystalline polyester resin unit and the amorphous polyester resin unit do not have a portion where the units react with each other, a system in which the crystalline polyester resin unit and the amorphous polyester resin unit coexist is formed. A method may be adopted in which a compound having a site capable of binding to the crystalline polyester resin unit and the amorphous polyester resin unit is charged therein. Then, a hybrid resin having a structure in which a crystalline polyester resin unit and an amorphous polyester resin unit are chemically bonded may be synthesized via the compound.

(3) A method in which a crystalline polyester resin unit is formed in advance and a polymerization reaction for forming an amorphous polyester resin unit is carried out in the presence of the crystalline polyester resin unit to synthesize a hybrid resin. , Polyvalent carboxylic acid and polyhydric alcohol are subjected to a condensation reaction to carry out polymerization to form a crystalline polyester resin unit. Next, in the presence of the crystalline polyester resin unit, the monomers constituting the amorphous polyester resin unit are polymerized to form the amorphous polyester resin unit. At this time, as in the above method (1), it is preferable that the crystalline polyester resin unit or the amorphous polyester resin unit has a portion where these units react with each other. As a method of incorporating a site where both units react with each other, the same method as the above-mentioned method (1) may be used.

By the above method, a hybrid resin having a structure (graft structure) in which an amorphous polyester resin unit is chemically bonded to a crystalline polyester resin unit can be formed.

Among the methods for synthesizing the hybrid resin (1) to (3), the method (1) makes it easy to form a hybrid resin having a structure in which a crystalline polyester resin chain is grafted on the side chain of the amorphous polyester resin, and , It is preferable because the production process can be simplified. Further, the method (1) is preferable from the viewpoint that the orientation of the crystalline polyester resin unit tends to be uniform because the crystalline polyester resin unit is bonded after the amorphous polyester resin unit is formed in advance.

The content of the crystalline polyester resin unit with respect to the hybrid resin is preferably 50% by mass or more and 98% by mass or less from the viewpoint of imparting sufficient crystallinity to the hybrid resin.

The content of the hybrid resin with respect to the mold release agent is preferably 200% by mass or more and 500% by mass or less, preferably 200% by mass or less, from the viewpoint of obtaining a toner having low temperature fixing property and suppressing the occurrence of cold offset in a low temperature environment. It is more preferably mass% or more and 400 mass% or less, and further preferably 250 mass% or more and 350 mass% or less.

The content of the hybrid resin with respect to the entire toner particles is preferably 30% by mass or more and less than 50% by mass, preferably 30% by mass or more, from the viewpoint of obtaining a toner having low-temperature fixability and suppressing the occurrence of cold offset in a low-temperature environment. It is more preferably mass% or more and less than 48% by mass, and further preferably 35% by mass or more and less than 45% by mass.

The weight average molecular weight (Mw) of the hybrid resin is preferably 5,000 or more and 100,000 or less, more preferably 7,000 or more and 50,000 or less, and 8,000 or more and 20,000 or less from the viewpoint of having low temperature fixability of the toner. More preferred.

The molecular weight distribution (Mw / Mn) of the hybrid resin is preferably 1.5 or more and 100 or less, and 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 by using Tosoh's GPC / HLC-8120GPC as a measuring device, using Tosoh's column / TSKgel SuperHM-M (15 cm), and using a THF solvent. The weight average molecular weight and the number average molecular weight are calculated from this measurement result using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample.

The "crystallinity" of the resin means that in differential scanning calorimetry (DSC), it has a clear endothermic peak rather than a stepwise endothermic change, and specifically, the temperature rise rate is 10 (° C./min). ) Indicates that the half-value width of the endothermic peak is within 10 ° C.
On the other hand, "amorphous" of the resin means that the half width exceeds 10 ° C., shows a stepwise change in endothermic amount, or does not show a clear endothermic peak.

The melting temperature of the hybrid resin is preferably 55 ° C. or higher and 85 ° C. or lower, more preferably 60 ° C. or higher and 80 ° C. or lower.

The melting temperature of the hybrid resin is determined from the DSC curve obtained by differential scanning calorimetry (DSC) measurement by 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". .. As more specific temperature raising and cooling conditions, the first heating process in which the temperature is raised from room temperature (25 ° C.) to 150 ° C. at an ascending / descending speed of 10 ° C./min and kept at a constant temperature of 150 ° C. for 5 minutes, the cooling speed is 10. The cooling process of cooling from 150 ° C. to 0 ° C. at ° C./min and maintaining the same temperature at 0 ° C. for 5 minutes, and the second temperature raising process of raising the temperature from 0 ° C. to 150 ° C. at an ascending / descending speed of 10 ° C./min are performed. It was measured in order. In the above measurement, the top temperature of the melting peak derived from the crystalline polyester resin unit in the first temperature raising process was defined as the melting temperature (endothermic peak temperature) of the hybrid resin.

The amorphous polyester resin unit in the hybrid resin does not have a melting point and has a glass transition point (Tg). The glass transition temperature derived from the amorphous polyester resin unit is preferably 30 ° C. or higher and 90 ° C. or lower, and more preferably 40 ° C. or higher and 75 ° C. or lower in the temperature raising process of the DSC measurement described above.

(Vinyl resin)
Hereinafter, the vinyl resin will be described.
The binder resin of the present embodiment includes a vinyl-based resin.

The vinyl-based resin refers to a resin obtained by radical polymerization of a monomer having a vinyl group (hereinafter referred to as "vinyl-based monomer"). The vinyl-based resin is a homopolymer obtained by polymerizing one kind of vinyl-based monomer or a copolymer obtained by polymerizing two or more kinds of vinyl-based monomers. May be good.

Examples of the vinyl resin include a monomer having a styrene skeleton (for example, styrene, parachlorostyrene, α-methylstyrene, etc.), a monomer having a (meth) acrylic acid ester skeleton (for example, methyl acrylate, etc.). 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. ), Monomer having an ethylenically unsaturated nitrile skeleton (for example, acrylonitrile, methacrylonitrile, etc.), Monomer having a vinyl ether skeleton (for example, vinyl methyl ether, vinyl isobutyl ether, etc.), Monomer having a vinyl ketone skeleton. A homopolymer of a monomer such as a body (for example, vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone, etc.), a monomer having an olefin skeleton (for example, ethylene, propylene, butadiene, etc.), or a single amount thereof. Examples thereof include a copolymer in which two or more kinds of bodies are combined.

Among the above, the vinyl resin is a styrene (meth) acrylic resin obtained by copolymerizing a monomer having a styrene skeleton and a monomer having a (meth) acrylic acid ester skeleton from the viewpoint of having low-temperature fixability. It is preferable to have.

The styrene (meth) acrylic resin is a copolymer obtained by at least copolymerizing a monomer having a styrene skeleton and a monomer having a (meth) acryloyl group. "(Meta) acrylic acid" is an expression including both "acrylic acid" and "methacrylic acid". Further, the "(meth) acryloyl group" is an expression including both "acryloyl group" and "methacryloyl group".

Examples of the monomer having a styrene skeleton (hereinafter referred to as “styrene-based monomer”) include styrene and alkyl-substituted styrene (for example, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene). Examples thereof include methyl styrene, 2-ethyl styrene, 3-ethyl styrene, 4-ethyl styrene, etc.), halogen-substituted styrene (for example, 2-chloro styrene, 3-chloro styrene, 4-chloro styrene, etc.), vinyl naphthalene and the like. The styrene-based monomer may be used alone or in combination of two or more.
Among these, as the styrene-based monomer, styrene is preferable in terms of ease of reaction, ease of control of reaction, and availability.

Examples of the monomer having a (meth) acryloyl group (hereinafter referred to as “(meth) acrylic monomer”) include (meth) acrylic acid and (meth) acrylic acid ester. Examples of the (meth) acrylic acid ester include (meth) acrylic acid alkyl ester (for example, (meth) acrylic acid n-methyl, (meth) acrylic acid n-ethyl, (meth) acrylic acid n-propyl, and (meth) acrylic acid ester. ) N-butyl acrylate, n-pentyl (meth) acrylate, n-hexyl acrylate, n-heptyl (meth) acrylate, n-octyl (meth) acrylate, n-decyl (meth) acrylate, (meth) N-dodecyl (meth) acrylate, n-lauryl (meth) acrylate, n-tetradecyl (meth) acrylate, n-hexadecyl (meth) acrylate, n-octadecyl (meth) acrylate, isopropyl (meth) acrylate. , (Meta) isobutyl acrylate, (meth) t-butyl acrylate, (meth) isopentyl acrylate, (meth) amyl acrylate, (meth) neopentyl acrylate, (meth) isohexyl acrylate, (meth) acrylate Isoheptyl, (meth) acrylate isooctyl, (meth) acrylate 2-ethylhexyl, (meth) acrylate cyclohexyl, (meth) acrylate t-butylcyclohexyl, etc.), (meth) acrylate aryl ester (eg, (meth) Phenyl acrylate, biphenyl (meth) acrylate, diphenylethyl (meth) acrylate, t-butylphenyl (meth) acrylate, terphenyl (meth) acrylate, etc.), dimethylaminoethyl (meth) acrylate, (meth) ) Diethylaminoethyl acrylate, methoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, β-carboxyethyl (meth) acrylate, (meth) acrylamide and the like. The (meth) acrylic acid-based monomer may be used alone or in combination of two or more.

The copolymerization ratio (mass basis, styrene-based monomer / (meth) acrylic-based monomer) between the styrene-based monomer and the (meth) acrylic-based monomer is, for example, 85/15 to 70/30. That's good.

The styrene (meth) acrylic resin preferably has a crosslinked structure in terms of suppressing image set-off. The styrene (meth) acrylic resin having a crosslinked structure is, for example, crosslinked by at least copolymerizing a monomer having a styrene skeleton, a monomer having a (meth) acrylic acid skeleton, and a crosslinkable monomer. Things can be mentioned.

Examples of the crosslinkable monomer include bifunctional or higher functional crosslinkers.
Examples of the bifunctional cross-linking agent include divinylbenzene, divinylnaphthalene, and di (meth) acrylate compounds (for example, diethylene glycol di (meth) acrylate, methylenebis (meth) acrylamide, decanediol diacrylate, glycidyl (meth) acrylate, etc.). , Polyester-type di (meth) acrylate, 2-([1'-methylpropanolamino] carboxyamino) ethyl methacrylate and the like.
Examples of the polyfunctional cross-linking agent include tri (meth) acrylate compounds (for example, pentaerythritol tri (meth) acrylate, trimethylolethanetri (meth) acrylate, trimethylolpropane tri (meth) acrylate, etc.) and tetra (meth) acrylate. Compounds (eg, tetramethylolmethanetetra (meth) acrylate, oligoester (meth) acrylate, etc.), 2,2-bis (4-methacryloxy, polyethoxyphenyl) propane, diallylphthalate, triallyl cyanurate, triallyl assocyanurate. , Triallyl isocyanurate, triallyl trimellitate, diallyl chlorendate and the like.

The copolymerization ratio of the crosslinkable monomer to all the monomers (mass basis, crosslinkable monomer / total monomer) is preferably, for example, 2/1000 or more and 30/1000 or less.

The weight average molecular weight of the styrene (meth) acrylic resin is, for example, preferably 30,000 or more and 200,000 or less, preferably 40,000 or more and 100,000 or less, and more preferably 50,000 or more and 80,000 or less in terms of suppressing image set-off.
The weight average molecular weight of the styrene (meth) acrylic resin is measured by the same method as the weight average molecular weight of the polyester resin.

The content of the styrene (meth) acrylic resin with respect to the vinyl resin is preferably 90% by mass or more and 100% by mass or less, and more preferably 98% by mass or more and 100% by mass or less.
The content of the vinyl-based resin with respect to the binder resin is, for example, preferably 10% by mass or more and 30% by mass or less, preferably 12% by mass or more and 28% by mass or less, and more preferably 15% by mass or more and 25% by mass or less.

(Release agent)
Hereinafter, the release agent will be described.
The toner particles of the present embodiment contain a mold release agent.

Examples of the release agent include hydrocarbon waxes; natural waxes such as carnauba wax, rice wax and candelilla wax; synthetic or mineral / petroleum waxes such as montan wax; ester waxes such as fatty acid esters and montanic acid esters. ; And so on. The release agent is not limited to this.

The melting temperature of the release agent is preferably 50 ° C. or higher and 110 ° C. or lower, and more preferably 60 ° C. or higher and 100 ° C. or lower.

The difference between the melting temperature of the release agent and the melting temperature of the hybrid resin is preferably 49 ° C. or lower, more preferably 40 ° C. or lower, further preferably 35 ° C. or lower, and 0 ° C. Is particularly preferred.

When the difference between the melting temperature of the release agent and the melting temperature of the hybrid resin is 49 ° C or less, the viscosity decreases and melts in a narrow temperature range (sharp melt property), and the toner has low temperature fixability. Tend to have.

The melting temperature is obtained in the same manner as the measurement of the melting temperature of the hybrid resin.

The content of the release agent with respect to the toner particles is preferably 3% by mass or more and less than 30% by mass, and 5% by mass or more and 25% by mass or less, from the viewpoint of obtaining a toner that suppresses the occurrence of cold offset in a low temperature environment. It is more preferable that it is 5% by mass or more and 20% by mass or less.

[External agent]
Examples of the external additive include inorganic particles. As the inorganic particles, SiO ₂ , TiO ₂ , Al ₂ O ₃ , CuO, ZnO, SnO ₂ , CeO ₂ , Fe ₂ O ₃ , MgO, BaO, CaO, K ₂ O, Na ₂ O, ZrO ₂ , CaO. _Examples thereof include SiO ₂ , K ₂ O · (TiO ₂ ) n, Al ₂ O 3.2SiO ₂ , CaCO ₃ , MgCO ₃ , BaSO ₄ , _Л4 and the like.

The surface of the inorganic particles as an external additive should be hydrophobized. The hydrophobizing treatment is performed, for example, by immersing the inorganic particles in the hydrophobizing agent. The hydrophobizing agent is not particularly limited, and examples thereof include a silane-based coupling agent, a silicone oil, a titanate-based coupling agent, and an aluminum-based coupling agent. 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.

Examples of the resin particles of the external additive include resin particles such as polystyrene, polymethylmethacrylate (PMMA), and melamine resin.
Examples of the cleaning active agent for the external additive include metal salts of higher fatty acids typified by zinc stearate, particles of fluorine-based high molecular weight substances, and the like.

The amount of the external additive added is, for example, preferably 0.01% by mass or more and 5% by mass or less, and more preferably 0.01% by mass or more and 2.0% by mass or less with respect to the toner particles.

[Toner manufacturing method]
The toner according to the present embodiment is produced, for example, by producing toner particles and externally adding an externalizing agent to the toner particles.

The toner particles may be produced by any of a dry production method (for example, a kneading and pulverizing method, etc.) and a wet production method (for example, an agglomeration coalescence method, a suspension polymerization method, a dissolution suspension method, etc.). There are no particular restrictions on these manufacturing methods, and well-known manufacturing methods are adopted. Above all, it is preferable to obtain toner particles by the aggregation and coalescence method.

Specifically, for example, when the toner particles are produced by the aggregation and coalescence method,
A step of preparing a hybrid resin particle dispersion liquid in which hybrid resin particles are dispersed (hybrid resin particle dispersion liquid preparation step);
A step of preparing a vinyl-based resin particle dispersion liquid in which vinyl-based resin particles are dispersed (vinyl-based resin particle dispersion liquid preparation step);
A step of preparing a release agent particle dispersion liquid in which mold release agent particles are dispersed (a step of preparing a release agent particle dispersion liquid);
In a mixed dispersion in which a release agent particle dispersion and a vinyl resin particle dispersion are mixed (in a dispersion in which other particle dispersions such as a colorant are also mixed if necessary), the mixed particles are aggregated. , The step of forming the first agglomerated particles (first agglomerated particle forming step);
A step of mixing the first agglomerated particle dispersion liquid in which the first agglomerated particles are dispersed and the hybrid resin particle dispersion liquid to form the second agglomerated particles (second agglomerated particle forming step);
The step of heating the second agglomerated particle dispersion liquid in which the second agglomerated particles are dispersed and fusing and coalescing the second agglomerated particles to form toner particles (fusion and union step);
Toner particles are manufactured.

Hereinafter, details of each step of the aggregation and coalescence method will be described. In the following description, a method for obtaining toner particles containing a colorant will be described, but the colorant is used as needed. Of course, other additives other than the colorant may be used.

-Each dispersion preparation process-
First, a resin particle dispersion in which hybrid resin particles were dispersed, a vinyl resin particle dispersion in which vinyl resin particles were dispersed, a colorant dispersion in which colorant particles were dispersed, and a release agent particle were dispersed. Prepare a release agent particle dispersion.

The hybrid resin particle dispersion liquid is prepared, for example, by dispersing the hybrid resin particles in a dispersion medium with a surfactant.

Examples of the dispersion medium used in the hybrid resin particle dispersion liquid include an aqueous medium.
Examples of the aqueous medium include distilled water, water such as ion-exchanged water; alcohols; and the like. These may be used alone or in combination of two or more.

Examples of the surfactant include anionic surfactants such as sulfate ester salt type, sulfonate type, phosphoric acid ester type and soap type; cationic surfactants such as amine salt type and quaternary ammonium salt type; polyethylene glycol. Non-ionic surfactants such as systems, alkylphenol ethylene oxide adducts, and polyhydric alcohols; and the like. Among these, anionic surfactants and cationic surfactants are particularly mentioned. The nonionic surfactant may be used in combination with an anionic surfactant or a cationic surfactant.
One type of surfactant may be used alone, or two or more types may be used in combination.

Examples of the method for dispersing the hybrid resin particles in the dispersion medium include a general dispersion method using a rotary shear homogenizer, a ball mill having a medium, a sand mill, a dyno mill, and the like. Alternatively, the hybrid resin particles may be dispersed in a dispersion medium by a phase inversion emulsification method. In the phase inversion emulsification method, the resin to be dispersed is dissolved in a hydrophobic organic solvent in which the resin is soluble, and the organic continuous phase (O phase) is neutralized by adding a base, and then water (W phase). This is a method in which the phase is changed from W / O to O / W by charging the resin, and the resin is dispersed in an aqueous medium in the form of particles.

Similar to the hybrid resin particle dispersion, a vinyl resin particle dispersion, a colorant dispersion, and a release agent particle dispersion are also prepared. That is, the dispersion medium, the dispersion method, the volume average particle diameter of the particles, and the content of the particles in the hybrid resin particle dispersion are the same in the vinyl resin particle dispersion, the colorant dispersion, and the release agent particle dispersion. Is.

-First aggregate particle forming step-
In the first agglomerated particle forming step, the release agent particle dispersion liquid, the vinyl resin particle dispersion liquid, and the colorant dispersion liquid are mixed.
Then, in the mixed dispersion, the release agent particles, the vinyl-based resin particles, and the colorant particles are heteroaggregated, and the release agent particles and the vinyl-based resin particles have a diameter close to the particle size of the target toner particles. To form first agglomerated particles containing the colorant particles and the colorant particles.

Specifically, for example, a flocculant is added to the mixed dispersion, the pH of the mixed dispersion is adjusted to be acidic (for example, pH 2 or more and 5 or less), a dispersion stabilizer is added as necessary, and then a vinyl-based solution is used. The particles are heated to a temperature close to the glass transition temperature of the resin particles (specifically, for example, the glass transition temperature of vinyl-based resin particles is -30 ° C or higher and the glass transition temperature is -10 ° C or lower), and the particles are dispersed in the mixed dispersion. The particles are aggregated to form the first aggregated particles.
In the first agglomerated particle forming step, for example, the mixed dispersion is stirred with a rotary shear homogenizer, the flocculant is added at room temperature (for example, 25 ° C.), and the pH of the mixed dispersion is acidic (for example, pH 2 or more and 5 or less). If necessary, a dispersion stabilizer may be added, and then heating may be performed.

Examples of the flocculant include a surfactant contained in the mixed dispersion and a surfactant having the opposite polarity, an inorganic metal salt, and a metal complex having a valence of 2 or more. When a metal complex is used as the flocculant, the amount of the flocculant used is reduced and the charging characteristics are improved.
Along with the flocculant, an additive that forms a complex or similar bond with the metal ion of the flocculant may be used. As this additive, a chelating agent is preferably used.

Examples of the inorganic metal salt include metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride and aluminum sulfate; and inorganic metal salts such as polyaluminum chloride, polyaluminum hydroxide and calcium polysulfide. Polymer; etc.
As the chelating agent, a water-soluble chelating agent may be used. Examples of the chelating agent include oxycarboxylic acids such as tartrate acid, citric acid and gluconic acid; aminocarboxylic acids such as iminodiacetic acid (IDA), nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA); ..
The amount of the chelating agent added is, for example, preferably 0.01 parts by mass or more and 5.0 parts by mass or less, and more preferably 0.1 parts by mass or more and less than 3.0 parts by mass with respect to 100 parts by mass of the resin particles.

The volume average particle diameter of the first agglomerated particles dispersed in the first agglomerated particle dispersion is, for example, preferably 2.0 μm or more and 4.0 μm or less, more preferably 3.0 μm or more and 4.0 μm or less, and 3.5 μm or more and 4 More preferably, it is 0.0 μm or less.
The volume average particle size of the first agglomerated particles is determined with respect to the divided particle size range (channel) using the particle size distribution obtained by the measurement of a laser diffraction type particle size distribution measuring device (for example, LA-700 manufactured by Horiba Seisakusho). The cumulative distribution of the volume is drawn from the small particle size side, and the particle size that is 50% of the total particle size is defined as the volume average particle size D50v. The volume average particle diameter of the particles in the other dispersion is also measured in the same manner.

-Second aggregate particle formation step-
In the first agglomerated particle forming step, when the volume average particle diameter of the first agglomerated particles dispersed in the first agglomerated particle dispersion liquid reaches the above-mentioned preferable volume average particle diameter range, the first agglomerated particle dispersion liquid is prepared. The hybrid resin particle dispersion is mixed stepwise at least three times with respect to the total amount. Next, the mixed dispersion is heated at a temperature equal to or lower than the glass transition temperature of the vinyl resin to adjust the pH of the mixed dispersion to, for example, 6.5 or more and 8.5 or less, and stop the progress of aggregation. As a result, a second agglomerated particle dispersion liquid in which the second agglomerated particles are dispersed is obtained.

When the hybrid resin particle dispersion liquid is mixed stepwise at least three times with respect to the total amount of the first aggregated particle dispersion liquid, the domain of the hybrid resin formed in the toner particles becomes the domain of the release agent. It is easy to take a state of being dispersed over the entire toner particles without being unevenly distributed on the surface. As a result, the occurrence of cold offset in a low temperature environment is likely to be suppressed.

-Fusion / unification process-
Next, the second agglomerated particle dispersion liquid in which the second agglomerated particles are dispersed is, for example, equal to or higher than the glass transition temperature of the vinyl-based resin (for example, a temperature higher than the glass transition temperature of the vinyl-based resin by 10 ° C to 50 ° C.). The second agglomerated particles are fused and united to form toner particles.
Toner particles can be obtained through the above steps, but the formulation in the agglomerated particle forming step is not limited to the above, and any formulation may be used.

After the completion of the fusion / coalescence step, the toner particles formed in the solution are subjected to a known cleaning step, solid-liquid separation step, and drying step to obtain a dried toner particle.
In the cleaning step, it is preferable to sufficiently perform replacement cleaning with ion-exchanged water from the viewpoint of chargeability. The solid-liquid separation step is not particularly limited, but suction filtration, pressure filtration and the like may be performed from the viewpoint of productivity. The drying step is also not particularly limited, but from the viewpoint of productivity, freeze-drying, flash jet drying, fluid drying, vibration-type fluid drying and the like may be performed.

The toner according to the present embodiment is produced, for example, by adding an external additive to the toner particles in a dry state and mixing them. The mixing may be performed by, for example, a V blender, a Henschel mixer, a Ladyge mixer or the like. Further, if necessary, the coarse particles of the toner may be removed by using a vibration master, a wind master, or the like.

<Image forming device / Image forming method>
An image forming apparatus and an image forming method according to the present embodiment will be described.
The image forming apparatus according to the present embodiment includes an image holder, a charging means for charging the surface of the image holder, a static charge image forming means for forming an electrostatic charge image on the surface of the charged image holder, and an electrostatic charge. A developing means that accommodates an image developer and develops a static charge image formed on the surface of the image holder as a toner image by the static charge image developer, and a recording medium that records the toner image formed on the surface of the image holder. It is provided with a transfer means for transferring to the surface of the recording medium and a fixing means for fixing the toner image transferred to the surface of the recording medium. Then, as the static charge image developer, the static charge image developer according to the present embodiment is applied.

In the image forming apparatus according to the present embodiment, a charging step of charging the surface of the image holder, a static charge image forming step of forming an electrostatic charge image on the surface of the charged image holder, and an electrostatic charge according to the present embodiment. A development step of developing an electrostatic charge image formed on the surface of an image holder as a toner image with an image developer, and a transfer step of transferring a toner image formed on the surface of the image holder to the surface of a recording medium. An image forming method (image forming method according to the present embodiment) having a fixing step of fixing a toner image transferred to the surface of a recording medium is carried out.

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 holder to the recording medium; the toner image formed on the surface of the image holder is transferred to the intermediate transfer body. An intermediate transfer type device that first transfers the toner image to the surface and then secondarily transfers the toner image transferred to the surface of the intermediate transfer body to the surface of the recording medium; after the toner image is transferred, the surface of the image holder before charging is cleaned. A well-known image forming apparatus such as a device provided with a cleaning means; a device provided with a static elimination means for irradiating the surface of an image holder with static elimination light after transfer of a toner image and before charging; is applied.
When the image forming apparatus according to the present embodiment is an intermediate transfer type apparatus, the transfer means is, for example, an intermediate transfer body in which a toner image is transferred to the surface and an intermediate transfer body in which the toner image formed on the surface of the image holder is transferred. A configuration having a primary transfer means for primary transfer to the surface of the body and a secondary transfer means for secondary transfer of the toner image transferred to the surface of the intermediate transfer body to the surface of the recording medium is applied.

In the image forming apparatus according to the present embodiment, for example, the portion including the developing means may have a cartridge structure (process cartridge) attached to and detached from the image forming apparatus. As the process cartridge, for example, a process cartridge provided with a developing means containing the electrostatic charge image developer according to the present embodiment is preferably used.

Hereinafter, an example of the image forming apparatus according to the present embodiment will be described, but the present invention is not limited thereto. In the following description, the main parts shown in the figure will be described, and the description thereof will be omitted.

FIG. 3 is a schematic configuration diagram showing an image forming apparatus according to the present embodiment.
The image forming apparatus shown in FIG. 3 is the first electrophotographic method that outputs images of each color of yellow (Y), magenta (M), cyan (C), and black (K) based on color-separated image data. A fourth image forming unit 10Y, 10M, 10C, and 10K (image forming means) is provided. These image forming units (hereinafter, may be simply referred to as "units") 10Y, 10M, 10C, and 10K are arranged side by side at a predetermined distance from each other in the horizontal direction. These units 10Y, 10M, 10C, and 10K may be process cartridges attached to and detached from the image forming apparatus.

Above each unit 10Y, 10M, 10C, and 10K, an intermediate transfer belt (an example of an intermediate transfer body) 20 is extended through each unit. The intermediate transfer belt 20 is provided by being wound around a drive roll 22 and a support roll 24 that are in contact with the inner surface of the intermediate transfer belt 20, and travels in a direction from the first unit 10Y to the fourth unit 10K. There is. A force is applied to the support roll 24 in a direction away from the drive roll 22 by a spring or the like (not shown), and tension is applied to the intermediate transfer belt 20 wound around the support roll 24. An intermediate transfer body cleaning device 30 is provided on the image holding surface side of the intermediate transfer belt 20 so as to face the drive roll 22.
Developing equipment for each unit 10Y, 10M, 10C, 10K (an example of developing means) Yellow, magenta, cyan, and black contained in toner cartridges 8Y, 8M, 8C, and 8K for each of 4Y, 4M, 4C, and 4K. Each toner is supplied.

Since the first to fourth units 10Y, 10M, 10C, and 10K have the same configuration, operation, and operation, the yellow image arranged on the upstream side in the intermediate transfer belt traveling direction is shown here. The first unit 10Y to be formed will be described as a representative.

The first unit 10Y has a photoconductor 1Y that acts as an image holder. Around the photoconductor 1Y, a charging roll (an example of charging means) 2Y that charges the surface of the photoconductor 1Y to a predetermined potential, and a laser beam 3Y based on a color-decomposed image signal expose the charged surface. An exposure device (an example of a static charge image forming means) 3 for forming an electrostatic charge image, and a developing device (an example of a developing means) 4Y for developing a static charge image by supplying a charged toner to the static charge image. A primary transfer roll (an example of a primary transfer means) 5Y that transfers a toner image onto an intermediate transfer belt 20, and a photoconductor cleaning device (an example of a cleaning means) 6Y that removes toner remaining on the surface of the photoconductor 1Y after the primary transfer. Are arranged in order.
The primary transfer roll 5Y is arranged inside the intermediate transfer belt 20 and is provided at a position facing the photoconductor 1Y. A bias power supply (not shown) for applying a primary transfer bias is connected to each of the primary transfer rolls 5Y, 5M, 5C, and 5K of each unit. Each bias power supply changes the value of the transfer bias applied to each primary transfer roll by control by a control unit (not shown).

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 photoconductor 1Y is charged to a potential of −600 V to −800 V by the charging roll 2Y.
The photoconductor 1Y is formed by laminating a photosensitive layer on a conductive substrate (for example, a volume resistivity of 1 × 10 ^-6 Ωcm or less at 20 ° C.). This photosensitive layer usually has a high resistance (resistance of a general resin), but has a property that when a laser beam is irradiated, the specific resistance of the portion irradiated with the laser beam changes. Therefore, the surface of the charged photoconductor 1Y is irradiated with the laser beam 3Y from the exposure apparatus 3 according to the image data for yellow sent from the control unit (not shown). As a result, an electrostatic charge image of the yellow image pattern is formed on the surface of the photoconductor 1Y.

The static charge image is an image formed on the surface of the photoconductor 1Y by charging, and the specific resistance of the irradiated portion of the photosensitive layer is lowered by the laser beam 3Y, and the charged charge on the surface of the photoconductor 1Y flows. On the other hand, it is a so-called negative latent image formed by the residual charge of the portion not irradiated with the laser beam 3Y.
The electrostatic charge image formed on the photoconductor 1Y rotates to a predetermined development position as the photoconductor 1Y runs. Then, at this developing position, the electrostatic charge image on the photoconductor 1Y is developed and visualized as a toner image by the developing device 4Y.

In the developing apparatus 4Y, for example, a static charge image developing agent containing at least a yellow toner and a carrier is housed. The yellow toner is triboelectrically charged by being agitated inside the developing apparatus 4Y, and has a charge having the same polarity (negative electrode property) as the charged charge on the photoconductor 1Y, and is a developer roll (developer holder). Example) It is held on. Then, as the surface of the photoconductor 1Y passes through the developing device 4Y, the yellow toner is electrostatically adhered to the statically eliminated latent image portion on the surface of the photoconductor 1Y, and the latent image is developed by the yellow toner. Toner. The photoconductor 1Y on which the yellow toner image is formed is continuously traveled at a predetermined speed, and the toner image developed on the photoconductor 1Y is conveyed to a predetermined primary transfer position.

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

The primary transfer bias applied to the primary transfer rolls 5M, 5C, and 5K after the second unit 10M is also controlled according to the first unit.
In this way, the intermediate transfer belt 20 to which the yellow toner image is 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 superimposed and multiplex transferred. Toner.

The intermediate transfer belt 20 to which the toner images of four colors are multiplex-transferred through the first to fourth units includes the intermediate transfer belt 20, the support roll 24 in contact with the inner surface of the intermediate transfer belt, and the image holding surface of the intermediate transfer belt 20. It leads to a secondary transfer unit composed of a secondary transfer roll (an example of the secondary transfer means) 26 arranged on the side. On the other hand, the recording paper (an example of the recording medium) P is fed to the gap where the secondary transfer roll 26 and the intermediate transfer belt 20 are in contact with each other via the supply mechanism at a predetermined timing, and the secondary transfer bias is supported by the support roll. It is applied to 24. The transfer bias applied at this time has the same polarity (-) as the toner polarity (-), and the electrostatic force from the intermediate transfer belt 20 toward the recording paper P acts on the toner image, and the transfer bias is applied to the intermediate transfer belt 20. The toner image of is transferred onto the recording paper P. The secondary transfer bias at this time is determined according to the resistance detected by the resistance detecting means (not shown) for detecting the resistance of the secondary transfer unit, and is voltage controlled.

After that, the recording paper P is sent to the pressure contact portion (nip portion) of the pair of fixing rolls in the fixing device (an example of the fixing means) 28, the toner image is fixed on the recording paper P, and the fixing image is formed. ..

Examples of the recording paper P for transferring the toner image include plain paper used in electrophotographic copying machines, printers, and the like. Examples of the recording medium include an OHP sheet and the like in addition to the recording paper P.
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 in which the surface of plain paper is coated with resin or the like, art paper for printing, or the like is used. It is preferably used.

The recording paper P for which the fixing of the color image is completed is carried out toward the ejection unit, and a series of color image forming operations is completed.

<Process cartridge / toner cartridge>
The process cartridge according to this embodiment will be described.
The process cartridge according to the present embodiment contains the electrostatic charge image developer according to the present embodiment, and is a developing means for developing the electrostatic charge image formed on the surface of the image holder as a toner image by the electrostatic charge image developer. It is a process cartridge that is attached to and detached from the image forming apparatus.

The process cartridge according to the present embodiment is not limited to the above configuration, and can be selected from a developing device and other means such as an image holder, a charging means, a static charge image forming means, and a transfer means, if necessary. It may be configured to include at least one of the above.

Hereinafter, an example of the process cartridge according to the present embodiment will be shown, but the present invention is not limited thereto. In the following description, the main parts shown in the figure will be described, and the description thereof will be omitted.

FIG. 4 is a schematic configuration diagram showing a process cartridge according to the present embodiment.
The process cartridge 200 shown in FIG. 4 is provided around the photoconductor 107 (an example of an image holder) and the periphery of the photoconductor 107 by, for example, a housing 117 provided with a mounting rail 116 and an opening 118 for exposure. The charged roll 108 (an example of the charging means), the developing device 111 (an example of the developing means), and the photoconductor cleaning device 113 (an example of the cleaning means) are integrally combined and held and configured to form a cartridge. There is.
In FIG. 4, 109 is an exposure device (an example of an electrostatic charge image forming means), 112 is a transfer device (an example of a transfer means), 115 is a fixing device (an example of a fixing means), and 300 is a recording paper (an example of a recording medium). Is shown.

Next, the toner cartridge according to this 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 attached to and detached from the image forming apparatus. The toner cartridge accommodates a replenishing toner to be supplied to the developing means provided in the image forming apparatus.

The image forming apparatus shown in FIG. 3 is an image forming apparatus having a structure in which toner cartridges 8Y, 8M, 8C, and 8K are attached and detached, and the developing apparatus 4Y, 4M, 4C, and 4K are toner cartridges corresponding to the respective colors. Is connected by a toner supply pipe (not shown). When the amount of toner contained in the toner cartridge is low, the toner cartridge is replaced.

Hereinafter, the present embodiment will be described in more detail with reference to examples, but the present embodiment is not limited to these examples. In the following description, "parts" and "%" indicating quantities are based on mass unless otherwise specified.

―Synthesis example of hybrid resin―
(Solution forming amorphous polyester resin unit: Preparation of AmPEs solution)
Polycarboxylic acid compounds (2.1 parts by mass of terephthalic acid, 0.2 parts by mass of fumaric acid, and 0.5 parts by mass of trimellitic acid) and polyhydric alcohols (2,2-bis (4-hydroxyphenyl) propane). 1.5 parts by mass of ethylene oxide 2 mol adduct (BPA-EO) and 5 parts by mass of 2,2-bis (4-hydroxyphenyl) propanpropylene oxide 2 mol adduct (BPA-PO)) and polyvalent carboxylic acid The esterification catalyst Ti (OBu) ₄ in an amount of 0.003% by mass based on the total amount of the acid monomer was mixed and placed in a dropping funnel.

(Solution forming crystalline polyester resin unit: Preparation of CPEs solution)
A polyvalent carboxylic acid compound (99 parts by mass of 1,12-dodecane diic acid) and a polyhydric alcohol (38 parts by mass of 1,9-nonanediol) are provided with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple. It was placed in a four-necked flask and heated to 170 ° C. to dissolve it.

(Synthesis of hybrid resin)
The four-necked flask containing the CPEs solution was provided with a dropping funnel containing the AmPEs solution, and the AmPEs solution was added dropwise over 90 minutes under stirring, and the reaction was carried out at room temperature for 60 minutes. Then, the unreacted addition polymerization monomer was removed under reduced pressure (8 kPa).
Next, 0.8 parts by mass of the esterification catalyst (Ti (OBu) ₄ ) was added to the above reaction system, the temperature was raised to 235 ° C., and the temperature was further reduced under normal pressure (101.3 kPa) for 5 hours. The reaction was carried out at 8 kPa) for 1 hour. Then, the mixture was cooled to 200 ° C. and reacted under reduced pressure (20 kPa) for 1 hour to obtain a hybrid resin.

The obtained hybrid resin was a resin in which a crystalline polyester resin unit was grafted onto an amorphous polyester resin unit. The weight average molecular weight (Mw) of the hybrid resin was 16000, and the melting temperature was 74 ° C.

-Preparation for preparation of dispersion-
[Hybrid resin particle dispersion: Preparation of HB (1)]
The hybrid resin obtained above was dispersed using a disperser obtained by modifying Cavitron CD1010 (manufactured by Eurotec Ltd.) into a high-temperature and high-pressure type. With a composition ratio of 80% ion-exchanged water and 20% concentration of hybrid resin, the pH is adjusted to 8.5 with ammonia, the rotation speed of the rotor is 60 Hz, the pressure is 5 kg / cm ² , and the heating by the heat exchanger is 140. The Cavitron was operated under the condition of ° C. to obtain a hybrid resin particle dispersion.
The volume average particle diameter of the hybrid resin particles in this dispersion was 205 nm. Ion-exchanged water was added to the dispersion to adjust the solid content to 20%, and this was used as a hybrid resin particle dispersion (HB (1)).

[Hybrid resin particle dispersion: Preparation of HB (2)]
A hybrid resin dispersion (HB (2)) was obtained in the same manner as in HB (1) except that the pressure was 7.5 kg / cm ² and the heating using a heat exchanger was 150 ° C. The volume average particle diameter of the hybrid resin particles in this dispersion was 170 nm.

[Hybrid resin particle dispersion: Preparation of HB (3)]
A hybrid resin dispersion (HB (3)) was obtained in the same manner as in HB (1) except that the pressure was 5 kg / cm ² and the heating using a heat exchanger was 130 ° C. The volume average particle diameter of the hybrid resin particles in this dispersion was 300 nm.

[Hybrid resin particle dispersion: Preparation of HB (4)]
A hybrid resin dispersion (HB (4)) was obtained in the same manner as in HB (1) except that the pressure was 8 kg / cm ² and the heating using a heat exchanger was 155 ° C. The volume average particle diameter of the hybrid resin particles in this dispersion was 150 nm.

[Preparation of vinyl-based resin particle dispersion]
(Preparation of styrene (meth) acrylic resin particle dispersion)
-Styline: 77 parts-n-butyl acrylate: 23 parts-1,10-decanediol diacrylate: 0.4 parts-Dodecanthiol: 0.7 parts Anionic surfactant in a mixture of the above materials. (Dowfax manufactured by Dow Chemical Co., Ltd.) A solution prepared by dissolving 1.0 part in 60 parts of ion-exchanged water was added and dispersed and emulsified in a flask to prepare a dispersion.
Subsequently, 2.0 parts of an anionic surfactant (Dowfax manufactured by Dow Chemical Co., Ltd.) was dissolved in 90 parts of ion-exchanged water, 2.0 parts of the above-mentioned raw material emulsion was added thereto, and ammonium persulfate was further added. 10 parts of ion-exchanged water in which 1.0 part was dissolved was added.
After that, the rest of the emulsion of the above raw materials was added over 3 hours to replace the nitrogen in the flask, and then the solution in the flask was heated in an oil bath to 65 ° C. while stirring and emulsified as it was for 5 hours. The polymerization was continued to obtain a styrene (meth) acrylic resin particle dispersion. The solid content of the styrene (meth) acrylic resin particle dispersion was adjusted to 32% by adding ion-exchanged water.
The volume average particle size of the styrene (meth) acrylic resin particles in the styrene (meth) acrylic resin particle dispersion was 220 nm, and the weight average molecular weight (Mw) was 32000.

(Preparation of (meth) acrylic acid ester resin particle dispersion liquid)
-N-Butyl methacrylate: 90 parts-Acrylic acid: 0.5 parts-1,10-Decandiol diacrylate: 0.5 parts-Dodecanthiol: 0.8 parts Anionic in a mixture of the above materials. A solution prepared by dissolving 1.0 part of a surfactant (Dowfax manufactured by Dow Chemical Co., Ltd.) in 60 parts of ion-exchanged water was added and dispersed and emulsified in a flask to prepare a dispersion.
Subsequently, 2.0 parts of an anionic surfactant (Dowfax manufactured by Dow Chemical Co., Ltd.) was dissolved in 90 parts of ion-exchanged water, 2.0 parts of the above-mentioned raw material emulsion was added thereto, and ammonium persulfate was further added. 10 parts of ion-exchanged water in which 1.0 part was dissolved was added.
After that, the rest of the emulsion of the above raw materials was added over 3 hours to replace the nitrogen in the flask, and then the solution in the flask was heated in an oil bath to 65 ° C. while stirring and emulsified as it was for 5 hours. The polymerization was continued to obtain a (meth) acrylic acid ester resin particle dispersion. The solid content of the (meth) acrylic acid ester resin particle dispersion was adjusted to 32% by adding ion-exchanged water. The volume average particle diameter of the (meth) acrylic acid ester resin particles in the (meth) acrylic acid ester resin particle dispersion was 160 nm, and the weight average molecular weight (Mw) was 35,000.

[Colorant dispersion: Preparation of black pigment dispersion]
-Carbon black (Regal330 manufactured by Cabot): 250 parts-Anionic surfactant (Neogen SC manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.): 33 parts (active ingredient 60%, 8% with respect to colorant)
-Ion-exchanged water: 750 parts In a stainless steel container with a size that the height of the liquid level becomes about 1/3 of the height of the container when all the above materials are added, 280 parts of ion-exchanged water and anionic surfactant After adding 33 parts of the agent and sufficiently dissolving the surfactant, all the carbon black was added, and the mixture was stirred with a stirrer until the non-wet pigment disappeared, and the foam was sufficiently defoamed. After defoaming, the remaining ion-exchanged water was added, and the mixture was dispersed at 5000 rpm for 10 minutes using a homogenizer (Ultratarax T50 manufactured by IKA), and then defoamed by stirring with a stirrer for 1 day and night. After defoaming, the mixture was dispersed again at 6000 rpm for 10 minutes using a homogenizer, and then stirred with a stirrer for 1 day and night to defoam. Subsequently, the dispersion liquid was dispersed at a pressure of 240 MPa using a high-pressure impact disperser Ultimizer (HJP30006 manufactured by Sugino Machine Limited). Dispersion was performed equivalent to 25 passes in terms of the total charge amount and the processing capacity of the apparatus. The obtained dispersion was left to stand for 72 hours to remove the precipitate, and ion-exchanged water was added to adjust the solid content to 15% to obtain a black pigment dispersion. The volume average particle diameter of the particles in the black pigment dispersion was 135 nm.

[Release Dispersion Solution: Preparation of WAX (1)]
-Polyethylene wax (hydrocarbon wax, Baker Petrolite polywax 725, melting temperature 104 ° C): 270 parts-Anionic surfactant (Neogen RK, Daiichi Kogyo Seiyaku Co., Ltd.): 13.5 parts (active ingredient 60) %, 3% for mold release agent)
-Ion-exchanged water: 21.6 parts The above materials were mixed and the release agent was dissolved at an internal liquid temperature of 120 ° C. with a pressure discharge homogenizer (Gorin homogenizer manufactured by Gorin Co., Ltd.). Then, the dispersion treatment was carried out at a dispersion pressure of 5 MPa for 120 minutes and then at 40 MPa for 360 minutes, and the mixture was cooled to obtain a release agent dispersion liquid. Ion-exchanged water was added to adjust the solid content to 20%, and this was used as a release agent particle dispersion (WAX (1)). The volume average particle diameter of the particles in the release agent particle dispersion liquid (WAX (1)) was 260 nm.

[Release Dispersion Solution: Preparation of WAX (2)]
-Polyethylene wax (hydrocarbon wax, manufactured by Mitsui Chemicals, Inc., 800PF, melting temperature 133 ° C): 270 parts-Anionic surfactant (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., Neogen RK): 13.5 parts ( As an active ingredient, 3.0% of the release agent)
-Ion exchanged water: 21.6 parts Mix the above components, dissolve the release agent at an internal liquid temperature of 120 ° C. with a pressure discharge homogenizer (Gorin homogenizer, manufactured by Gorin), and then dissolve the mold release agent at a dispersion pressure of 5 MPa for 120 minutes. Then, the dispersion treatment was carried out at 40 MPa for 360 minutes, and the mixture was cooled to obtain a release agent particle dispersion liquid (WAX (2)). Then, ion-exchanged water was added to adjust the solid content to 20.0%. The volume average particle diameter of the particles in the de-economic particle dispersion (WAX (2)) was 250 nm.

-Manufacturing of toner particles-
[Example 1]
(First aggregate particle forming step)
-Removing agent particle dispersion (WAX (1)): 188 parts-Styline (meth) acrylic resin particle dispersion: 297 parts-Black pigment dispersion: 117 parts-Ion exchange water: 399 parts-Anionic surfactant (Doufax2A1 manufactured by Dow Chemical Co., Ltd.): 13 parts Put the above materials in a 3 liter reaction vessel equipped with a thermometer, pH meter and stirrer, add 1.0% nitrate at a temperature of 25 ° C, and adjust the pH. Adjusted to 3.0. Then, while dispersing at 5,000 rpm with a homogenizer (Ultratalax T50 manufactured by IKA), 100 parts of a 2.0% concentrated magnesium chloride aqueous solution was added as a coagulant and dispersed for 6 minutes.
After that, a stirrer and a mantle heater are installed in the reaction vessel, and while adjusting the rotation speed of the stirrer so that the slurry is sufficiently agitated, the temperature rise rate is 0.2 ° C./min up to a temperature of 40 ° C., 40. The temperature was raised from above ° C. to 53 ° C. at a heating rate of 0.05 ° C./min, and the particle size was measured every 10 minutes with Multisizer II (aperture diameter 50 μm, manufactured by Beckman-Coulter). The temperature was maintained when the volume average particle diameter reached 3.7 μm, and this was used as the first aggregated particle dispersion.

(Second agglomerated particle forming step)
167 parts of the hybrid resin particle dispersion (HB (1)) is mixed with the above-mentioned first agglomerated particle dispersion, and dispersed and aggregated at 5,000 rpm with a homogenizer (Ultratalax T50 manufactured by IKA) for 10 minutes. The step of making the particles was divided into three steps and performed step by step. The temperature was maintained when the volume average particle diameter reached 7.0 μm, and this was used as the second aggregated particle dispersion.

(Fusion / unification process)
After holding at 50 ° C. for 30 minutes, 8 parts of a 20% solution of EDTA (ethylenediaminetetraacetic acid) was added to the reaction vessel. Then, a 1 mol / L sodium hydroxide aqueous solution was added to control the pH of the raw material dispersion to 9.0. Next, while adjusting the pH to 9.0 every 5 ° C., the temperature was raised to 90 ° C. at a heating rate of 1 ° C./min and maintained at 90 ° C. The shape and surface properties of the particles were observed with an optical microscope and a field emission scanning electron microscope (FE-SEM), and at the 6th hour when the coalescence of the particles was confirmed, the container was cooled to 30 ° C for 5 minutes with cooling water. It was cooled over.

The cooled slurry was passed through a nylon mesh having an opening of 15 μm to remove coarse powder, and the toner slurry that had passed through the mesh was filtered under reduced pressure with an aspirator. The solid content remaining on the filter paper was crushed as finely as possible by hand, poured into ion-exchanged water having a temperature of 30 ° C., which was 10 times the solid content, and stirred and mixed for 30 minutes. Next, the mixture is vacuum-filtered with an ejector, the solid content remaining on the filter paper is crushed by hand as finely as possible, poured into ion-exchanged water at a temperature of 30 ° C., which is 10 times the solid content, stirred and mixed for 30 minutes, and then again with an ejector. Filtration was performed under reduced pressure, and the electrical conductivity of the filtrate was measured. This operation was repeated until the electric conductivity of the filtrate became 10 μS / cm or less, and the solid content was washed.
The washed solid content was finely crushed with a wet dry granulator (comil) and vacuum dried in an oven at 35 ° C. for 36 hours to obtain toner particles. The toner particles had a volume average particle diameter of 6.6 μm.

(Addition of external additive)
Next, 1.5 parts of hydrophobic silica (RY50 manufactured by Nippon Aerosil Co., Ltd.) was added to 100 parts of the obtained toner particles, and the mixture was mixed at 13000 rpm for 30 seconds using a sample mill. Then, the toner was sieved with a vibrating sieve having an opening of 45 μm to obtain the toner of Example 1.

[Examples 2 to 4, 8 to 13 and Comparative Examples 3 to 4]
In Example 1, the types and number of copies of the binder resin and the mold release agent were changed to the specifications shown in Table 1. Further, the number of copies and the manufacturing operation of the hybrid resin particle dispersion liquid, the vinyl resin particle dispersion liquid, and the release agent particle dispersion liquid in the toner particle production of Example 1 were set to the specifications shown in Table 2 to obtain a toner.

[Example 5]
The same operation as in Example 1 was performed except that the (meth) acrylic acid ester resin particle dispersion was used instead of the styrene (meth) acrylic resin particle dispersion.

[Example 6]
The same operation as in Example 1 was carried out except that the amount of the anionic surfactant (Dowfax2A1 manufactured by Dow Chemical Co., Ltd.) was 18 parts and the hybrid resin particle dispersion was HB (3).

[Example 7]
The same operation as in Example 1 was carried out except that the amount of the anionic surfactant (Dowfax2A1 manufactured by Dow Chemical Co., Ltd.) was 10 parts.

[Comparative Example 1]
In Example 1, toner was obtained in the same manner as in Example 1 except that the first agglomerated particle forming step and the second agglomerated particle forming step were changed to the following specifications as one agglomerated particle forming step.
-Release agent particle dispersion (WAX (1)): 188 parts-Hybrid resin particle dispersion (HB (1)): 500 parts-Vinyl resin particle dispersion: 297 parts-Black pigment dispersion: 117 parts- Ion-exchanged water: 399 parts, anionic surfactant (Doufax2A1 manufactured by Dow Chemical Co., Ltd.): 13 parts Put the above materials in a 3 liter reaction vessel equipped with a thermometer, pH meter, and stirrer, and keep the temperature at 25 ° C. Then 1.0% nitrate was added to adjust the pH to 3.0. Then, while dispersing at 5,000 rpm with a homogenizer (Ultratalax T50 manufactured by IKA), 100 parts of a 2.0% concentrated magnesium chloride aqueous solution was added as a coagulant and dispersed for 6 minutes.
After that, a stirrer and a mantle heater are installed in the reaction vessel, and while adjusting the rotation speed of the stirrer so that the slurry is sufficiently agitated, the temperature rise rate is 0.2 ° C./min up to a temperature of 40 ° C., 40. The temperature was raised from above ° C. to 53 ° C. at a heating rate of 0.05 ° C./min, and the particle size was measured every 10 minutes with Multisizer II (aperture diameter 50 μm, manufactured by Beckman-Coulter). The temperature was maintained when the volume average particle diameter reached 3.8 μm, and this was used as an aggregated particle dispersion.

[Comparative Example 2]
In Example 1, in the second aggregate particle forming step of Example 1, the following styrene acrylic modified polyester resin particle dispersion liquid (ST (1)) is used instead of the hybrid resin particle dispersion liquid (HB (1)). Toner was obtained as a specification.

[Styrene acrylic modified polyester resin particle dispersion: Preparation of ST (1)]
The inside of a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane 5670 parts. , Polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane 585 parts, terephthalic acid 2450 parts and di (2-ethylhexanoic acid) 44 parts, and stir in a nitrogen atmosphere. The temperature was raised to 235 ° C. and maintained for 5 hours, then the pressure in the flask was further reduced, and the temperature was maintained at 8.0 kPa for 1 hour. After returning to atmospheric pressure, the mixture was cooled to 190 ° C., 42 parts of fumaric acid and 207 parts of trimellitic acid were added, maintained at a temperature of 190 ° C. for 2 hours, and then heated to 210 ° C. over 2 hours. Further, the pressure in the flask was lowered and maintained at 8.0 kPa for 4 hours to obtain an amorphous polyester resin A (polyester segment).
Next, 857 parts of the amorphous polyester resin A was added to a 4-necked flask equipped with a cooling tube, a stirrer and a thermocouple and having an internal volume of 2 liters, and the mixture was stirred under a nitrogen atmosphere at a stirring speed of 200 rpm. Then, 60 parts of styrene, 60 parts of ethyl acrylate and 500 parts of ethyl acetate were added as addition-polymerizable monomers, and the mixture was further mixed for 30 minutes.
Furthermore, 6 parts of polyoxyethylene alkyl ether (nonionic surfactant, trade name: Emargen 430, manufactured by Kao Co., Ltd.), 15% sodium dodecylbenzene sulfonate solution (anionic surfactant, trade name: Neoperex) Add 40 parts of G-15 (manufactured by Kao Co., Ltd.) and 233 parts of 5% potassium hydroxide, heat the temperature to 95 ° C to melt while stirring, and mix at 95 ° C for 2 hours to prepare a resin mixture solution. Obtained.
Next, while stirring the resin mixture solution, 1145 parts of deionized water was added dropwise at a rate of 6 parts / minute to obtain an emulsion. Next, the obtained emulsion was cooled to 25 ° C., passed through a 200 mesh wire mesh, and deionized water was added to adjust the solid content to 20%, and the styrene acrylic modified polyester resin particle dispersion liquid (ST (ST). 1)) was obtained.

[Comparative Example 5]
In Example 1, instead of the hybrid resin particle dispersion liquid (HB (1)) in which the crystalline polyester resin unit and the amorphous polyester resin unit are chemically bonded, the crystalline polyester resin unit and the amorphous polyurethane resin unit are chemically bonded. A toner was obtained by using a bonded resin particle dispersion (PUT (1)).

[Synthesis of crystalline polyester resin unit]
A polyhydric alcohol component (215 parts by mass), a polyvalent carboxylic acid component (346 parts by mass of sebacic acid), and a polymerization catalyst were placed in a reaction vessel equipped with a cooling can, a stirrer, a decompression device, and a nitrogen introduction tube. (1 part by mass of tetrabutoxytitanate) was added, and the temperature was raised to 180 ° C. The reaction was carried out for 5 hours while distilling off the water generated under the nitrogen stream at the same temperature. Then, the reaction was further carried out under a reduced pressure of 0.02 MPa while distilling off water, and when the acid value reached 0.1 mgKOH / g, the mixture was taken out to obtain a crystalline polyester resin unit (crystalline polyester diol).

[Synthesis of a resin obtained by chemically bonding a crystalline polyester resin unit and an amorphous polyurethane resin unit]
In a reaction vessel equipped with a cooling can, a stirrer, a decompression device and a nitrogen introduction tube, 500 parts by mass of dehydrated methyl ethyl ketone, 452 parts by mass of the above-mentioned crystalline polyester resin unit (crystalline polyester diol), and 2,2-dimethylol propionic acid. 15 parts by mass was added, and the mixture was stirred at 60 ° C. for 1 hour to melt it. Next, 33 parts by mass of hexamethylene diisocyanate was added to this solution under a nitrogen stream, the internal temperature was raised to 80 ° C. with stirring, and the mixture was reacted for 12 hours. Then, 13 parts by mass of trimellitic anhydride and 0.5 part by mass of tetrabutoxytitanate as a catalyst were added, and the reaction was carried out at 120 ° C. for 5 hours. Then, methyl ethyl ketone was distilled off to obtain a resin in which a crystalline polyester resin unit and an amorphous polyurethane resin unit were chemically bonded. The melting temperature of the obtained resin was 71 ° C.

[Resin particle dispersion liquid in which a crystalline polyester resin unit and an amorphous polyurethane resin unit are chemically bonded: Preparation of PUT (1)]
A resin particle dispersion (PUT (1)) was prepared in the same manner as in HB (1) except that a resin in which a crystalline polyester resin unit and an amorphous polyurethane resin unit were chemically bonded was used instead of the hybrid resin. Prepared.

<Measurement>
For the toners obtained in each example, the average area ratio, average number, and average diameter of the domain of the release agent and the domain of the hybrid resin existing in the region within 100 nm from the surface of the domain of the release agent have already been obtained. It was measured according to the method described above. The measurement results are shown in Table 2.

<Evaluation>
Using the toners obtained in each example, an electrostatic latent image developer was prepared as follows. Then, the fixability was evaluated using the obtained electrostatic latent image developer. The evaluation results are shown in Table 2.

-Evaluation of fixability-
The prepared developer was filled in the developing apparatus of the evaluation machine "D136 Light Publicer (manufactured by Fuji Xerox Co., Ltd.)". Using this evaluation machine, the fixability was evaluated as follows.
The electrostatic charge image developer obtained in each example was filled in a developer of a color copier DocuCenter IV C3370 (manufactured by Fuji Xerox Co., Ltd.) from which the fuser was taken out so that the toner loading amount was 13.5 g / m ² . Adjusted and output an unfixed image. J paper was used as the recording medium, and an unfixed image having an image density of 100% and a size of 25 mm × 25 mm was formed on one side. As the fixing evaluation device, the fixing device of ApeosPort IV C3370 manufactured by Fuji Xerox Co., Ltd. was removed and modified so that the fixing temperature could be changed.
The nip width of the fuser was 6 mm, the nip pressure was 1.6 kgf / cm ² , the Dwell_time was 34.7 ms, and the process speed was 175 mm / sec. The temperature was raised from 80 ° C. to 220 ° C. at intervals of 5 ° C. to fix the unfixed image, and a cold offset (caused by the toner image not being sufficiently heated) was visually displayed on the fixing member. The presence or absence of transitional development) was confirmed, and the temperature at which the cold offset disappeared was evaluated as the cold offset disappearance temperature. This was used as an index of low temperature fixability. Fixability was evaluated based on the following evaluation criteria.
-Fixability evaluation criteria-
A: Less than 110 ° C B: 110 ° C or more and less than 120 ° C C: 120 ° C or more and less than 130 ° C D: 130 ° C or more and 140 degrees or less E: More than 140 ° C

From the above results, the toners of Examples 1 to 13 having the configuration of the present embodiment have low temperature fixability and suppress the occurrence of cold offset as compared with the toners of Comparative Examples 1 to 5. I understand.

1Y, 1M, 1C, 1K Photoreceptor (Example of image holder)
2Y, 2M, 2C, 2K Charging roll (an example of charging means)
3 Exposure device (an example of static charge image forming means)
3Y, 3M, 3C, 3K laser beam 4Y, 4M, 4C, 4K developing device (an example of developing means)
5Y, 5M, 5C, 5K primary transfer roll (an example of primary transfer means)
6Y, 6M, 6C, 6K Photoreceptor cleaning device (an example of cleaning means)
8Y, 8M, 8C, 8K Toner Cartridge 10Y, 10M, 10C, 10K Image Forming Unit 20 Intermediate Transfer Belt (Example of Intermediate Transfer)
22 Drive roll 24 Support roll 26 Secondary transfer roll (an example of secondary transfer means)
28 Fixing device (an example of fixing means)
30 Intermediate transfer element cleaning device P Recording paper (an example of recording medium)
107 Photoreceptor (an example of image holder)
108 Charging roll (an example of charging means)
109 Exposure device (an example of static charge image forming means)
111 Developing equipment (an example of developing means)
112 Transfer device (an example of transfer means)
113 Photoreceptor cleaning device (an example of cleaning means)
115 Fixing device (an example of fixing means)
116 Mounting rail 117 Housing 118 Opening for exposure 200 Process cartridge 300 Recording paper (an example of recording medium)
400 Continuous phase made of vinyl resin 500 Domain of mold release agent 600 Domain of hybrid resin 700 Toner particles

Claims (17)

A binder resin containing a hybrid resin obtained by chemically bonding a crystalline polyester resin unit and an amorphous polyester resin unit, a vinyl resin, and the like.
Release agent and
Has toner particles containing
The toner particles have the domain of the release agent and the domain of the hybrid resin.
The domain of the hybrid resin is present in a region within 100 nm from the surface of the domain of the release agent with an average area ratio of 10% or more and 20% or less .

A toner for static charge image development in which the average diameter of the domain of the release agent is 0.5 μm or more and less than 2 μm . A binder resin containing a hybrid resin obtained by chemically bonding a crystalline polyester resin unit and an amorphous polyester resin unit, a vinyl resin, and the like.
Release agent and
Has toner particles containing
The toner particles have the domain of the release agent and the domain of the hybrid resin.
In the region within 100 nm from the surface of the domain of the release agent, the domain of the hybrid resin is present in an average number of 2 or more and 7 or less .
A toner for static charge image development in which the average diameter of the domain of the release agent is 0.5 μm or more and less than 2 μm . The toner for static charge image development according to claim 1 or 2, wherein the vinyl resin is a styrene (meth) acrylic resin. The toner for static charge image development according to any one of claims 1 to 3, wherein the domain of the release agent has an average diameter of 0.6 μm or more and less than 1.5 μm. Claims 1 to 4 , wherein the ratio of the average diameter of the release agent domain to the average diameter of the domain of the hybrid resin is 1.2 / 0.5 or more and 1.1 / 0.1 or less. The toner for developing an electrostatic charge image according to any one of the items. Claim 1 that the ratio of the average area ratio of the domain of the mold release agent to the entire toner particles and the average area ratio of the domain of the hybrid resin to the entire toner particles is 10/50 or more and 30/17 or less. The toner for developing an electrostatic charge image according to any one of claims 5 . Claim 1 to claim that the ratio of the average number of domains of the release agent to the entire toner particles to the average number of domains of the hybrid resin to the entire toner particles is 16/50 or more and 20/25 or less. Item 6. The toner for developing an electrostatic charge image according to any one of Items 6. The toner for static charge image development according to any one of claims 1 to 7 , wherein the content of the mold release agent with respect to the toner particles is 3% by mass or more and less than 30% by mass. The toner for static charge image development according to any one of claims 1 to 8 , wherein the content of the hybrid resin with respect to the mold release agent is 200% by mass or more and 500% by mass or less. The toner for static charge image development according to any one of claims 1 to 9 , wherein the content of the hybrid resin with respect to the toner particles is 30% by mass or more and less than 50% by mass. The toner for static charge image development according to any one of claims 1 to 10 , wherein the difference between the melting temperature of the mold release agent and the melting temperature of the hybrid resin is 49 ° C. or less. The toner for developing an electrostatic charge image according to claim 11 , wherein the difference between the melting temperature of the mold release agent and the melting temperature of the hybrid resin is 35 ° C. or less. A static charge image developer containing the toner for static charge image development according to any one of claims 1 to 12 . The toner for static charge image development according to any one of claims 1 to 12 is accommodated.
A toner cartridge that is attached to and detached from the image forming device. A developing means for accommodating the electrostatic charge image developer according to claim 13 and developing the electrostatic charge image formed on the surface of the image holder as a toner image by the electrostatic charge image developer is provided.
A process cartridge that is attached to and detached from the image forming device. The charging process that charges the surface of the image holder,
A static charge image forming step of forming a static charge image on the surface of the charged image holder, and
A developing step of developing an electrostatic charge image formed on the surface of the image holder as a toner image by using the electrostatic charge image developer according to claim 13 .
A transfer step of transferring a toner image formed on the surface of the image holder to the surface of a recording medium, and
A fixing step of fixing the toner image transferred to the surface of the recording medium, and
Image forming method having. Image holder and
A charging means for charging the surface of the image holder, and
An electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image holder, and
A developing means for accommodating the electrostatic charge image developer according to claim 13 and developing the electrostatic charge image formed on the surface of the image holder as a toner image by the electrostatic charge image developer.
A transfer means for transferring a toner image formed on the surface of the image holder to the surface of a recording medium,
A fixing means for fixing the toner image transferred to the surface of the recording medium, and
An image forming apparatus.

Images