JP6627368B2 - Bright toner, electrostatic image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method - Google Patents

Description

  The present invention relates to a brilliant toner, an electrostatic image developer, a toner cartridge, a process cartridge, an image forming apparatus, and an image forming method.

A glitter toner using a metal pigment such as an aluminum pigment has been used to give a glitter to an image obtained by an electrophotographic method.
For example, Patent Document 1 discloses “a toner for developing an electrostatic image containing at least a binder resin, a colorant and a low-melting point compound, wherein the low-melting point compound has a maximum length of 0.1 to 1 μm in the toner. An endothermic peak area at 60 ° C. to 100 ° C. derived from the low melting point compound in an endothermic curve measured by a differential scanning calorimeter (DSC) at the time of the first temperature rise of the toner for developing an electrostatic charge image having a domain. Where A is the specific endothermic peak area at 60 ° C. to 100 ° C. derived from the low melting point compound in the DSC endothermic curve at the time of the second temperature increase, and B / A has a specific relationship. "Electrostatic image developing toner" is disclosed.
Patent Literature 2 discloses, “Electrostatic charge containing at least a binder resin mainly composed of a crystalline polyester resin containing an acid-derived component and an alcohol-derived component, a colorant, and a release agent. In the endothermic-exothermic curve of the differential thermal analysis based on ASTM D3418-8, there is a main endothermic maximum peak m1 having a peak temperature in the range of 55 to 80 ° C., and the main endothermic maximum peak m1. Is less than or equal to 20 ° C. and within a range of the peak temperature of the main endothermic maximum peak m1 ± 25 ° C., the shoulder s2 or other endothermic peak m2 on the low temperature side and the shoulder s3 or other on the high temperature side And the endothermic peak m3 is further present. "

JP-A-2006-267142 JP 2005-338339 A

  An object of the present invention is to include a flat glittering pigment, a crystalline resin, an amorphous resin, and a release agent, and perform a second heat absorption / heating curve in a differential thermal analysis based on ASTM D3418-8. In the temperature rising process, the toner has two endothermic peaks in the range of 60 ° C. or more and 100 ° C. or less, and has a low-speed fixing at a higher output than the case where the toner particles have a temperature difference between the two endothermic peaks exceeding 15 ° C. An object of the present invention is to provide a glitter toner capable of obtaining an image in which variation in glitter that occurs sometimes is suppressed.

The above problem is solved by the following means. That is,
The invention according to < 1 > ,
It contains a flat glittering pigment, a crystalline resin, an amorphous resin, and a release agent, and in the second heating process in the endothermic / exothermic curve of the differential thermal analysis based on ASTM D3418-8, 60 It has two or more endothermic peaks in the range of not less than 100 ° C and not more than 15 ° C, or one in the range of not less than 60 ° C and not more than 100 ° C. This is a glitter toner having an endothermic peak and having toner particles containing a compound corresponding to a crystalline resin and a release agent in the ethyl acetate-insoluble portion of the toner particles.

The invention according to < 2 > ,
The glitter toner according to < 1 > , wherein the toner particles include a urea-modified amorphous polyester resin as the amorphous resin.

The invention according to < 3 > ,
An electrostatic image developer containing the glitter toner according to < 1 > or < 2 > .

The invention according to < 4 > ,
Containing the glitter toner according to < 1 > or < 2 > ,
This is a toner cartridge that is detachably attached to the image forming apparatus.

The invention according to < 5 > ,
< 3 > a developing means for storing the electrostatic image developer according to < 3 >, and developing the electrostatic image formed on the surface of the image holding member as a toner image by the electrostatic image developer;
A process cartridge that is attached to and detached from the image forming apparatus.

The invention according to < 6 > ,
An image carrier,
Charging means for charging the surface of the image holding member,
Electrostatic image forming means for forming an electrostatic image on the surface of the charged image carrier,
Developing means for containing the electrostatic image developer according to < 3 >, and developing the electrostatic image formed on the surface of the image holding member as a toner image with the electrostatic image developer;
Transfer means for transferring the toner image formed on the surface of the image carrier to the surface of the recording medium,
Fixing means for fixing the toner image transferred to the surface of the recording medium,
It is an image forming apparatus provided with.

The invention according to < 7 > ,
A charging step of charging the surface of the image holding member,
An electrostatic image forming step of forming an electrostatic image on the surface of the charged image carrier,
A developing step of developing the electrostatic image formed on the surface of the image carrier as a toner image with the electrostatic image developer according to < 3 > ;
A transfer step of transferring the toner image formed on the surface of the image carrier to the surface of a recording medium,
A fixing step of fixing the toner image transferred to the surface of the recording medium,
Is an image forming method.

According to the invention according to < 1 > , an endothermic / exothermic curve of a differential thermal analysis based on ASTM D3418-8, comprising a flat bright pigment, a crystalline resin, an amorphous resin, and a release agent. Has two endothermic peaks in the range of 60 ° C. or more and 100 ° C. or less in the second heating process, and has a higher output speed than the case where the toner particles have a temperature difference between the two endothermic peaks exceeding 15 ° C. The present invention provides a brilliant toner capable of obtaining an image in which variability in brilliancy caused when the image is fixed at a low temperature is obtained.

According to the invention according to < 2 > , variation in glitter that occurs when the toner is fixed at a high speed and at a low temperature is suppressed as compared with the case where an unmodified amorphous polyester resin is included as the amorphous resin of the toner particles. There is provided a brilliant toner capable of obtaining an image and avoiding hot offset (a phenomenon in which a part of the toner adheres to a fixing member) due to a sharp decrease in toner viscosity during fixing.

According to the invention according to < 3 > , an endothermic / exothermic curve of a differential thermal analysis based on ASTM D3418-8, comprising a flat bright pigment, a crystalline resin, an amorphous resin, and a release agent. In the second heating process, a brilliant toner having toner particles having two endothermic peaks in a range of 60 ° C. or more and 100 ° C. or less and a difference in temperature between the two endothermic peaks exceeding 15 ° C. was applied. As compared with the case, there is provided an electrostatic charge image developer capable of obtaining an image in which variation in glitter that occurs when fixing is performed at high speed and at low temperature is suppressed.

According to the invention according to < 4 > , < 5 > , < 6 >, or < 7 > , it includes a flat glittering pigment, a crystalline resin, an amorphous resin, and a release agent, and includes ASTM D3418- 8 has two endothermic peaks in the range of 60 ° C. or more and 100 ° C. or less in the endothermic / exothermic curve of the differential endothermic curve of the differential thermal analysis based on No. 8, and the difference between the temperatures of the two endothermic peaks is 15 ° C. Toner cartridge, process cartridge, image forming apparatus, or image forming method capable of obtaining an image with reduced glittering variation that occurs when low-temperature fixing is performed at a high output speed, as compared with a case where a glittering toner having toner particles exceeding 50% is applied. Is provided.

FIG. 2 is a cross-sectional view schematically illustrating an example of a toner particle according to the exemplary embodiment. FIG. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an embodiment. FIG. 2 is a schematic configuration diagram illustrating an example of a process cartridge according to the embodiment.

  Hereinafter, an embodiment which is an example of the present invention will be described in detail.

<Glitter toner>
The glitter toner according to the present embodiment includes a flat glitter pigment (hereinafter, also simply referred to as “brilliant pigment”), a crystalline resin, an amorphous resin, and a release agent. In the second heating process in the endothermic / exothermic curve of the differential thermal analysis (hereinafter, also simply referred to as “endothermic / exothermic curve of differential thermal analysis”) in accordance with No. 8, two or more in the range of 60 ° C. or more and 100 ° C. or less And the difference between the temperatures of the two or more endothermic peaks is within 15 ° C. or one endothermic peak in the range of 60 ° C. to 100 ° C., and the acetic acid of the toner particles The toner particles include a compound corresponding to a crystalline resin and a release agent in an ethyl-insoluble portion. In specifying the compound, for example, FT-IR (Fourier transform infrared spectrophotometer) can be used.
Here, the temperature of the endothermic peak refers to the apex temperature (peak top) of the endothermic peak of the crystalline resin and the release agent contained in the toner particles, and the melting temperature (peak temperature) of the crystalline resin and the release agent, respectively. Melting point).
Hereinafter, the temperature of the endothermic peak of the crystalline resin may be referred to as the “melting temperature of the crystalline resin”. Further, the temperature of the endothermic peak of the release agent may be referred to as "melting temperature of the release agent".
“Having two or more endothermic peaks” means that the endothermic peak of the crystalline resin and the endothermic peak of the release agent fall within a range of 60 ° C. or more and 100 ° C. or less (hereinafter, also referred to as a specific temperature range). It means that there is one or more.
“The temperature difference between endothermic peaks is within 15 ° C.” refers to the difference between the temperature of the largest endothermic peak and the temperature of the smallest endothermic peak among the temperatures of two or more endothermic peaks within a specific temperature range. Is within 15 ° C.
“Having one endothermic peak” means that the endothermic peak of the crystalline resin and the endothermic peak of the release agent overlap to form one endothermic peak as a whole, and one endothermic peak is apparently present. Say. The term “one endothermic peak apparently exists” means that one or more endothermic peaks of the crystalline resin and one or more endothermic peaks of the release agent exist, but the temperature of the endothermic peak of the crystalline resin and the Since the difference between the temperature of the endothermic peak and the temperature is small (for example, less than 3 ° C.), it means that it appears to form one endothermic peak as a whole. For this reason, even if there is one endothermic peak, the one endothermic peak is derived from the endothermic peaks of the crystalline resin and the release agent. This is confirmed, for example, by analyzing the ethyl acetate insoluble content of the toner particles by FT-IR.
“Ethyl acetate insolubles in toner particles” refers to low molecular weight components insoluble in ethyl acetate among components contained in toner particles of the brilliant toner, such as a crystalline resin, an amorphous resin, Molding agents, etc. correspond.
The method for extracting the ethyl acetate-insoluble portion of the toner particles and the method for analyzing by FT-IR will be described later.

Here, a brilliant toner including a brilliant pigment (for example, a metal pigment such as an aluminum pigment) in toner particles in order to impart a brilliant feeling to an image obtained by electrophotography is known.
The brilliancy of an image by the brilliant toner is such that the brilliant pigment in the image is oriented along the surface of the recording medium (for example, paper), so that the brilliant pigment forms a mirror-like smooth surface, and the incident light is reduced. High brightness is exhibited by strong reflection.
In electrophotography using a brilliant toner, in order to orient the brilliant pigment in an image along the surface of a recording medium, a high temperature (for example, 180 ° C. or higher) is applied during fixing to lower the viscosity of the brilliant toner. There is a way. However, recently, environmental performance for suppressing power consumption of an image forming apparatus (for example, a printing machine and a copying machine) has been emphasized, and it is preferable to design the fixing temperature to be low.
Generally, as a technique for lowering the viscosity of a toner (including a brilliant toner, the same applies hereinafter) at a low fixing temperature (for example, 140 ° C. or more and 160 ° C. or less), a crystalline resin is used as a part of a binder resin of toner particles. The methods used are known. Crystalline resin has the property of lowering the viscosity and melting in a narrower temperature range (sharp melt property) than amorphous resin. The amount of heat required for fixing is adjusted according to the melting temperature and the amount added.
In addition, there is also known a method in which a release agent is contained in toner particles in order to suppress adhesion between a fixing member and a recording medium and promote peeling at the time of fixing by electrophotography. The release agent is liquefied by the heat at the time of fixing, and exudes at the boundary between the image and the fixing member to impart releasability.
These crystalline resins and the release agent are similar in terms of melting by heat at the time of fixing, but functionally, the crystalline resin adjusts the viscosity of the toner, and the release agent has a release property (release property). ) Is a functional material that is added for a different purpose of imparting.
On the other hand, in glittering toners, which have been attracting attention in recent years, it is important to design in consideration of the orientation of the glittering pigment in addition to the viscosity adjustment and releasability of the toner.
For example, when low-temperature fixing (for example, fixing at 140 ° C. or more and 160 ° C. or less) with high-speed output (for example, output at a conveying speed of a recording medium of 500 mm / sec) using a brilliant toner, a sufficient nip passing time (hereinafter, referred to as “fixing”) is used. It is necessary to fix the toner image in a state where the temperature of the fixing member is relatively hard to rise. In this case, since the fixing is performed without sufficiently lowering the viscosity of the glitter toner, it is considered that the glitter pigment in the image is less likely to be oriented along the surface of the recording medium. As a result, the brilliancy of the image obtained when the image is fixed at a high speed and at a low temperature is likely to be reduced, and the brilliancy is likely to be varied between the first sheet and the n-th sheet.

On the other hand, in the glitter toner according to the present embodiment, the toner particles contain a glitter pigment, a crystalline resin, an amorphous resin, and a release agent, and are subjected to endothermic thermal analysis. In the second heating process in the heat generation curve, 1) one or more endothermic peaks of the crystalline resin and one or more endothermic peaks of the release agent are present in a specific temperature range, and the endothermic peaks of these endothermic peaks are determined. Among the temperatures, toner particles in which the difference between the temperature of the maximum endothermic peak and the temperature of the minimum endothermic peak is adjusted to be within 15 ° C., or 2) the endothermic peak of the crystalline resin and the endothermic of the release agent The toner particles are adjusted so that the peaks overlap to form one endothermic peak as a whole. In the case of 2), the toner particles are adjusted so that the difference between the temperature of the endothermic peak of the crystalline resin and the temperature of the endothermic peak of the release agent is smaller than that in 1) (for example, less than 3 ° C.). is there.
In the glitter toner according to the present embodiment, by containing the toner particles having the above characteristics, it is possible to obtain an image in which variation in glitter which occurs when fixing is performed at high speed and at low temperature is suppressed.

The reason is not clear, but is presumed to be due to the following reason.
In this embodiment, from the viewpoint of realizing low-temperature fixing, the temperature of the endothermic peak of the crystalline resin contained in the toner particles and the endothermic peak of the release agent in the second heating process in the endothermic / exothermic curve of the differential thermal analysis. At a relatively low temperature of 60 ° C. or more and 100 ° C. or less. That is, the melting temperature of both the crystalline resin and the release agent contained in the toner particles is in the range of 60 ° C. or more and 100 ° C. or less.
In addition, the difference between the temperature of the endothermic peak of the crystalline resin and the temperature of the endothermic peak of the release agent should be within 15 ° C. in the case of 1), and even smaller (for example, less than 3 ° C.) in the case of 2). adjust.
Thereby, when the toner image is fixed, the melting timing of the crystalline resin and the release agent contained in the toner particles is approached, and the melting of both is accelerated. As a result, both the crystalline resin and the release agent are easily liquefied.
In addition, since both the crystalline resin and the release agent are easily liquefied, the amount of heat of the fixing member easily propagates in the toner image when the toner image is fixed.
Therefore, in the glitter toner according to the present embodiment, the difference between the temperature of the endothermic peak of the crystalline resin and the temperature of the endothermic peak of the release agent is reduced to within 15 ° C. Both the effect of being easily liquefied and the effect of easily transmitting the heat from the fixing member are synergistically expressed, so that the viscosity of the glittering toner as a whole tends to decrease more quickly and the glittering pigment in the image Are easily oriented along the surface of the recording medium.
As a result, even when the fixing member is easily deprived of heat and the low-temperature fixing is performed under the condition of high-speed output in which the temperature of the fixing member is relatively hard to rise, an image with good glittering property is easily obtained. (More than the number of sheets) The variation in the brilliancy between the first sheet and the n-th sheet upon output is likely to be suppressed.
From the above, according to the glitter toner according to the present embodiment, it is possible to obtain an image in which variation in glitter that occurs when fixing at a high speed and at a low temperature is suppressed.

  In the case of the toner particles according to the present embodiment, in the case of having two or more endothermic peaks in a specific temperature range in the second heating process in the endothermic / exothermic curve of the differential thermal analysis, the two or more endothermic peaks Is within 15 ° C., but is preferably within 10 ° C., and preferably within 5 ° C., from the viewpoint of obtaining an image in which variation in glitter that occurs when fixing at low temperature with high-speed output is more suppressed. More preferably, there is.

Further, the toner particles according to the exemplary embodiment have two or more endothermic peaks in a specific temperature range in the second heating process in the endothermic / exothermic curve of the differential thermal analysis, and have the two or more endothermic peaks. As a means for adjusting the difference in peak temperature to be within 15 ° C., for example, the melting temperature (hereinafter also referred to as the melting temperature of the crystalline resin alone) as measured by differential thermal analysis of the crystalline resin alone is used. The melting temperature of the crystalline resin in the range of 60 ° C. or more and 100 ° C. or less and the release agent alone as measured by differential thermal analysis (hereinafter also referred to as the melting temperature of the release agent alone) is 60 ° C. or more and 100 ° C. or less. And at least one type of release agent in the range described above, and further, a crystalline resin such that a difference between a maximum melting temperature and a minimum melting temperature among these melting temperatures is within 15 ° C. And release agent Allowed and a method used in.
As a means for adjusting so as to have one endothermic peak in a specific temperature range, as in the case of having two or more endothermic peaks, for example, the melting temperature of the crystalline resin alone is from 60 ° C to 100 ° C. After selecting one or more types of the crystalline resin in the following range and one or more release agents in which the melting temperature of the release agent alone is in the range of 60 ° C. or more and 100 ° C. or less, of these melting temperatures, And a method in which a crystalline resin and a release agent are used in combination such that the difference between the melting temperature and the minimum melting temperature is smaller (for example, less than 3 ° C.).

In the case where the toner particles in the present embodiment have two or more endothermic peaks in a specific temperature range in the second heating process in the endothermic / exothermic curve of the differential thermal analysis, the endothermic peak and the temperature of the endothermic peak are determined. The measuring method is as follows.
As the sample, toner particles obtained by removing an external additive from the brilliant toner are used.
The sample is placed on a differential scanning calorimeter (manufactured by Shimadzu Corporation: DSC-60A), and heated from room temperature (25 ° C.) to 150 ° C. at a rate of 10 ° C./min (first temperature rising process). Next, it is cooled to 0 ° C. at a rate of 10 ° C./min, and is heated again to 150 ° C. at a rate of 10 ° C./min (second heating process). At this time, it is left at 0 ° C. and 150 ° C. for 5 minutes each. From the endothermic / exothermic curve (based on ASTM D3418-8) of the differential thermal analysis obtained in the second heating process, the endothermic peak and the temperature of the endothermic peak are measured.
In the above measurement method, the determination as to which endothermic peak is a crystalline resin or a mold release agent indicates a relatively large amount of endotherm, and an endothermic / exothermic curve (chart) for the first and second temperature rises. ) Can be presumed to be a crystalline resin or a release agent if the peak shape does not change (which does not disappear by melting with other materials), but it can be more reliably determined by the FT-IR method described later. it can.

As a method of removing the external additive from the glitter toner, for example, the following method can be mentioned.
The brilliant toner is dispersed in an aqueous solution of 0.2% by mass of polyoxyethylene (10) octyl phenyl ether so as to have a concentration of 10% by mass, and ultrasonic vibration (frequency 20 kHz, output 30 W) is maintained while maintaining the temperature at 30 ° C. or lower. The external additive is released by acting for 60 minutes. The toner particles from which the external additive has been removed can be obtained by filtering and washing the toner particles from the dispersion.

When the toner particles in this embodiment have one endothermic peak in a specific temperature range, the one endothermic peak is derived from the endothermic peaks of the crystalline resin and the release agent. This means that, by the following method, the toner particles are extracted from the brilliant toner with ethyl acetate, and the “ethyl acetate insolubles” precipitated by cooling the extract to room temperature (25 ° C.) are analyzed by FT-IR. It is confirmed by detecting a compound corresponding to the crystalline resin and the release agent at the time of analysis.
First, ethyl acetate is charged as a solvent in a lower container of a Soxhlet extractor, and a brilliant toner as a sample is put on a central cylindrical filter paper. Next, the lower container is heated to 190 ° C. to condense the vapor of ethyl acetate, and the refluxed ethyl acetate is dropped on the sample (brilliant toner), and the solvent is extracted for 1 hour. As a result, the unextracted external additives and pigments remain on the thimble, and the solvent-extracted amorphous resin, crystalline resin, and release agent are contained in ethyl acetate. Then, the extract is cooled in a refrigerator for 1 hour, and the solid content is filtered with a 5C filter paper. The amorphous resin soluble in ethyl acetate at normal temperature (25 ° C) was separated, and the solid content collected on the filter paper was analyzed by FT-IR as a component insoluble in ethyl acetate. The crystalline resin and the release agent are specified by referring to the above database. Note that the above analysis may be performed using toner particles as a sample.
The database used is an IR database from BioRad.

The measurement conditions of FT-IR are as follows.
-Equipment used: FT-IR410 manufactured by JASCO Corporation
-Measuring method: KBR tablet method-Measuring conditions: Standard light source-Measuring range: 4000-400cm-1
・ Detector: TGS

Here, in the brilliant toner according to the present embodiment (hereinafter, also simply referred to as “toner”), “brilliant” means that the image formed by the brilliant toner has shine such as metallic luster when viewed visually. Represents
Specifically, when the solid image is formed, the toner according to the exemplary embodiment has a light receiving angle of + 30 ° measured when the image is irradiated with incident light having an incident angle of −45 ° by a goniophotometer. It is preferable that the ratio (X / Y) between the reflectance X at the point X and the reflectance Y at the light receiving angle of −30 ° is 2 or more and 100 or less.

When the ratio (X / Y) is 2 or more, the reflection on the side (angle + side) opposite to the side on which the incident light is incident is more than the reflection on the side (angle-side) on which the incident light is incident. That is, irregular reflection of incident light is suppressed. When diffused reflection occurs in which incident light is reflected in various directions, when the reflected light is visually checked, the color appears dull. Therefore, when the ratio (X / Y) is less than 2, gloss may not be confirmed even when the reflected light is visually recognized, and the glitter may be poor.
On the other hand, if the ratio (X / Y) exceeds 100, the viewing angle at which the reflected light can be viewed becomes too narrow, and the specular reflected light component is large, so that it may appear blackish depending on the viewing angle. Further, it is difficult to manufacture a toner having a ratio (X / Y) of more than 100.

  In addition, the ratio (X / Y) is more preferably 4 or more and 50 or less, further preferably 6 or more and 20 or less, and 8 or more and 15 or less from the viewpoints of glitter and toner productivity. Is particularly preferred.

-Measurement of ratio (X / Y) by goniophotometer-
Here, the incident angle and the light receiving angle will be described first. In the present embodiment, the angle of incidence is set to −45 ° when measuring with a goniophotometer, because the measurement sensitivity is high for images in a wide range of glossiness.
Further, the reason why the light receiving angles are set to -30 ° and + 30 ° is that the measurement sensitivity is highest for evaluating an image having a glitter and an image having no glitter.

Next, a method for measuring the ratio (X / Y) will be described.
Using a multi-angle colorimeter (BYK-Mac) manufactured by Toyo Seiki Co., Ltd. as a goniophotometer for the image to be measured (brilliant image), the incident light at an incident angle of -45 ° on the image is measured. Then, the reflectance X at a light receiving angle of + 30 ° and the reflectance Y at a light receiving angle of −30 ° are measured. The reflectivity X and the reflectivity Y were measured at intervals of 20 nm for light having a wavelength in the range of 400 nm to 700 nm, and the average value of the reflectivity at each wavelength was used. From these measurement results, the ratio (X / Y) is calculated.

The toner according to the exemplary embodiment preferably satisfies the following requirements (1) and (2) from the viewpoint of satisfying the above-mentioned ratio (X / Y).
(1) The average equivalent circle diameter D is longer than the average maximum thickness C of the toner particles.
(2) When the cross section in the thickness direction of the toner particles is observed, the brightness in which the angle between the long axis direction of the cross section of the toner particles and the long axis direction of the brilliant pigment is in the range of −30 ° to + 30 °. The proportion of the hydrophilic pigment is 60% or more of the total glitter pigment observed.

If the toner particles have a flat shape whose circular equivalent diameter is longer than the thickness (see FIG. 1), in the fixing step of image formation, the flat toner particles have a flat surface side on the surface of the recording medium due to a fixing pressure. It is thought that they are lined up opposite to each other. In FIG. 1, 2 indicates toner particles, 4 indicates a brilliant pigment, and L indicates the thickness of the toner particles.
For this reason, among the flat (flaky) glitter pigments contained in the toner particles, the angle between the long axis direction in the cross section of the toner particles and the long axis direction of the glitter pigment shown in the above (2) is referred to. Is in the range of −30 ° to + 30 ° ”, it is considered that the glittering pigments are arranged such that the surface side having the largest area faces the recording medium surface. When the image thus formed is irradiated with light, the ratio of the glitter pigment that irregularly reflects the incident light is suppressed, so that the above-mentioned range of the ratio (X / Y) is considered to be achieved. Can be

  Hereinafter, details of the toner according to the exemplary embodiment will be described.

  The toner according to the exemplary embodiment has toner particles. The toner may have an external additive added to the toner particles as needed.

(Toner particles)
The toner particles include a flat brilliant pigment, a binder resin, and a release agent. The toner particles may contain other additives as necessary.
In the present embodiment, a crystalline resin and an amorphous resin are used in combination as the binder resin. The mixing ratio of the crystalline resin to the amorphous resin is, for example, from 5:95 to 30:70 in terms of mass ratio from the viewpoint of obtaining an image in which the glitter variation caused when fixing at a high speed and at a low temperature is suppressed. It is preferable to be within the range up to. Further, the content of the binder resin is, for example, preferably from 40% by mass to 95% by mass, more preferably from 50% by mass to 90% by mass, and more preferably from 60% by mass to 85% by mass, based on the whole toner particles. The following are more preferred.

(Crystalline resin)
Examples of the crystalline resin include a crystalline polyester resin, a polyalkylene resin, and a long-chain alkyl (meth) acrylate resin. From the viewpoint of realizing low-temperature fixability, a crystalline polyester resin is preferable.
Here, the “crystallinity” of the resin refers to having a clear endothermic peak instead of a stepwise endothermic change in a differential thermal analysis (differential scanning calorimetry (DSC)) based on ASTM D3418-8. Specifically, it indicates that the half-value width of the endothermic peak measured at a heating rate of 10 (° C./min) is within 10 ° C.
On the other hand, “amorphous” of the resin indicates that the half-value width exceeds 10 ° C., that the resin exhibits a stepwise change in endothermic amount, or that no clear endothermic peak is observed.
The crystalline resin may be used at a content of 2% by mass or more and 40% by mass or less (preferably 2% by mass or more and 20% by mass or less) with respect to the whole binder resin.

The melting temperature of the crystalline resin is preferably from 60 ° C to 100 ° C, more preferably from 60 ° C to 80 ° C, as measured by differential thermal analysis (based on ASTM D3418-8) of the crystalline resin alone. More preferably, the temperature is 60 ° C. or more and 70 ° C. or less.
By setting the melting temperature of the crystalline resin alone in the above range, the temperature range of 60 ° C. or more and 100 ° C. or less in the second heating process in the endothermic / exothermic curve of the differential thermal analysis of the toner particles contained in the brilliant toner. The endothermic peak of the crystalline resin is easily obtained.
Hereinafter, a crystalline polyester resin will be described as an example of the crystalline resin, but the present invention is not limited thereto.

-Crystalline polyester resin The crystalline polyester resin is, for example, a polycondensate of a polyvalent carboxylic acid and a polyhydric alcohol. As the crystalline polyester resin, a commercially available product or a synthesized product may be used.
Here, in order to easily form a crystalline structure, the crystalline polyester resin is preferably a polycondensate using a polymerizable monomer having a linear aliphatic group rather than a polymerizable monomer having an aromatic group.

Examples of the polycarboxylic acid include aliphatic dicarboxylic acids (for example, oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid) Acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, etc., aromatic dicarboxylic acids (for example, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid) Dibasic acids such as acids), anhydrides thereof, and lower (for example, having 1 to 5 carbon atoms) alkyl esters thereof.
The polyvalent carboxylic acid may be used in combination with a dicarboxylic acid and a trivalent or higher carboxylic acid having a crosslinked structure or a branched structure. Examples of the trivalent carboxylic acid include aromatic carboxylic acids (eg, 1,2,3-benzenetricarboxylic acid, 1,2,4-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, etc.) Anhydrides and lower (e.g., 1 to 5 carbon atoms) alkyl esters thereof are exemplified.
As the polyvalent carboxylic acid, a dicarboxylic acid having a sulfonic acid group or a dicarboxylic acid having an ethylenic double bond may be used in combination with these dicarboxylic acids.
Polycarboxylic acids 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 to 20 carbon atoms in a 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- Octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18- Octadecanediol, 1,14-eicosandecanediol and the like can be mentioned. Among them, 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 together with the diol. Examples of the trivalent or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol.
Polyhydric alcohols may be used alone or in combination of two or more.

  Here, the polyhydric alcohol may have an aliphatic diol content of at least 80 mol%, preferably at least 90 mol%.

  The weight average molecular weight (Mw) of the crystalline polyester resin is preferably from 6,000 to 35,000.

  The crystalline polyester resin is obtained by a well-known manufacturing method, for example, similarly to the amorphous polyester resin described below.

(Amorphous resin)
Examples of the amorphous resin include a vinyl resin such as a styrene-acryl resin, an epoxy resin, polycarbonate, and polyurethane. From the viewpoint of realizing low-temperature fixability, an amorphous polyester resin is preferable.
The amorphous resin may be used in a content of 70% by mass or more and 95% by mass or less (preferably 80% by mass or more and 93% by mass or less) with respect to all the binder resins.
Hereinafter, an amorphous polyester resin will be described as an example of the amorphous resin, but the invention is not limited thereto.

-Amorphous polyester resin Examples of the amorphous polyester resin include a condensation polymer of a polyvalent carboxylic acid and a polyhydric alcohol. As the amorphous polyester resin, a commercially available product may be used, or a synthesized product may be used.

Examples of the polycarboxylic acid include aliphatic dicarboxylic acids (eg, oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, alkenylsuccinic acid, adipic acid, sebacic acid, etc.) , Alicyclic dicarboxylic acids (eg, cyclohexanedicarboxylic acid, etc.), aromatic dicarboxylic acids (eg, terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, etc.), anhydrides thereof, or lower (eg, having 1 or more carbon atoms) 5 or less) alkyl ester. Among them, as the polyvalent carboxylic acid, for example, an aromatic dicarboxylic acid is preferable.
The polyvalent carboxylic acid may be used in combination with a dicarboxylic acid and a trivalent or higher carboxylic acid having a crosslinked structure or a branched structure. Examples of the trivalent or higher carboxylic acid include trimellitic acid, pyromellitic acid, anhydrides thereof, and lower (for example, having 1 to 5 carbon atoms) alkyl esters thereof.
Polycarboxylic acids may be used alone or in combination of two or more.

Examples of polyhydric alcohols include aliphatic diols (eg, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, etc.), alicyclic diols (eg, cyclohexanediol, cyclohexanedimethanol, Hydrogenated bisphenol A) and aromatic diols (for example, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, etc.). Among these, as the polyhydric alcohol, for example, an aromatic diol and an alicyclic diol are preferable, and an aromatic diol is more preferable.
As the polyhydric alcohol, a trihydric or higher polyhydric alcohol having a crosslinked structure or a branched structure may be used together with the diol. Examples of the trihydric or higher polyhydric alcohol include glycerin, trimethylolpropane, and pentaerythritol.
Polyhydric alcohols may be used alone or in combination of two or more.

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

The weight average molecular weight (Mw) of the amorphous polyester resin is preferably from 5,000 to 1,000,000, and more preferably from 7000 to 500,000.
The number average molecular weight (Mn) of the amorphous polyester resin is preferably from 2,000 to 100,000.
The molecular weight distribution Mw / Mn of the amorphous polyester resin is preferably from 1.5 to 100, more preferably from 2 to 60.
In addition, a weight average molecular weight and a number average molecular weight are measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC is performed using a Tosoh column and TSKgel Super HM-M (15 cm) using a Tosoh GPC / HLC-8120GPC as a measuring device with a THF solvent. The weight average molecular weight and the number average molecular weight are calculated from the measurement results using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample.

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

  Here, examples of the amorphous polyester resin include a modified amorphous polyester resin in addition to the above-mentioned unmodified amorphous polyester resin. The modified amorphous polyester resin is an amorphous polyester resin having a bonding group other than an ester bond, and an amorphous polyester resin in which a resin component different from the amorphous polyester resin component is bonded by a covalent bond or an ionic bond. It is a polyester resin. Examples of the modified amorphous polyester resin include, for example, an amorphous polyester resin having a functional group such as an isocyanate group which reacts with an acid group or a hydroxyl group at a terminal, and a resin having a terminal modified by reacting with an active hydrogen compound. Is mentioned.

  As the modified amorphous polyester resin, a urea-modified amorphous polyester resin is particularly preferable. By including a urea-modified amorphous polyester resin as the binder resin, an image can be obtained in which the variation in glitter that occurs when the image is fixed at a high speed and at a low temperature is suppressed, and a sharp decrease in toner viscosity during fixing is obtained. The accompanying hot offset can also be avoided. This is because even when the toner rapidly liquefies in the fixing nip and the viscosity of the toner decreases due to the action of the crystalline resin having a melting temperature close to each other and the release agent, the elasticity of the urea-modified polyester causes a difference between the toners. It is considered that the action to supplement the binding force works. However, when a large amount of the urea-modified polyester is added, the viscosity of the toner at the time of fixing is hindered. Therefore, the content of the urea-modified amorphous polyester resin is 10% by mass or more with respect to the total binder resin. % By mass or less, more preferably 15% by mass or more and 30% by mass or less.

  The urea-modified amorphous polyester resin is a urea-modified amorphous resin obtained by reacting an amorphous polyester resin having an isocyanate group (amorphous polyester prepolymer) with an amine compound (at least one of a crosslinking reaction and an elongation reaction). Is preferred. The urea-modified amorphous polyester resin may contain a urethane bond together with a urea bond.

  As an amorphous polyester prepolymer having an isocyanate group, an amorphous polyester resin which is a polycondensate of a polyvalent carboxylic acid and a polyhydric alcohol, wherein the amorphous polyester resin having active hydrogen is a polyvalent isocyanate An amorphous polyester prepolymer obtained by reacting a compound can be used. Examples of the group having an active hydrogen contained in the amorphous polyester resin include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group and the like, and an alcoholic hydroxyl group is preferable.

  In the amorphous polyester prepolymer having an isocyanate group, the polycarboxylic acid and the polyhydric alcohol include the same compounds as the polyvalent carboxylic acid and the polyhydric alcohol described for the amorphous polyester resin.

Examples of the polyvalent isocyanate compound include aliphatic polyisocyanates (such as tetramethylene diisocyanate, hexamethylene diisocyanate, and 2,6-diisocyanatomethylcaproate); alicyclic polyisocyanates (such as isophorone diisocyanate and cyclohexylmethane diisocyanate); Diisocyanates (such as tolylene diisocyanate and diphenylmethane diisocyanate); araliphatic diisocyanates (such as α, α, α ′, α′-tetramethylxylylene diisocyanate); isocyanurates; and the polyisocyanates such as phenol derivatives, oximes and caprolactam. What blocked with the blocking agent is mentioned.
The polyvalent isocyanate compound may be used alone or in combination of two or more.

  The ratio of the polyvalent isocyanate compound is preferably an equivalent ratio [NCO] / [OH] of an isocyanate group [NCO] and a hydroxyl group [OH] of an amorphous polyester prepolymer having a hydroxyl group, preferably from 1/1 to 5/1. Or less, more preferably from 1.2 / 1 to 4/1, and still more preferably from 1.5 / 1 to 2.5 / 1. When [NCO] / [OH] is at least 1/1 and at most 5/1, it is easy to obtain an image in which variation in glitter is suppressed, and hot offset can be suppressed. When [NCO] / [OH] is 5 or less, a decrease in low-temperature fixability is easily suppressed.

  In the amorphous polyester prepolymer having an isocyanate group, the content of the component derived from the polyvalent isocyanate compound is preferably 0.5% by mass or more and 40% by mass relative to the entire amorphous polyester prepolymer having the isocyanate group. % Or less, more preferably 1 to 30% by mass, and still more preferably 2 to 20% by mass. When the content of the component derived from the polyvalent isocyanate is 0.5% by mass or more and 40% by mass or less, it is easy to obtain an image in which the glitter variation is suppressed, and the hot offset can be suppressed. When the content of the component derived from the polyvalent isocyanate is set to 40% by mass or less, a decrease in the low-temperature fixability is easily suppressed.

  The number of isocyanate groups contained in one molecule of the amorphous polyester prepolymer having isocyanate groups is preferably 1 or more on average, more preferably 1.5 or more and 3 or less on average, and still more preferably 1.8 or more on average. Not less than 2.5 and not more than 2.5. When the number of isocyanate groups is set to one or more per molecule, the molecular weight of the urea-modified amorphous polyester resin after the reaction increases, and it becomes easy to obtain an image in which variation in glitter is suppressed, and hot offset is suppressed. can do.

  Examples of the amine compound that reacts with the amorphous polyester prepolymer having an isocyanate group include diamine, trivalent or higher polyamine, amino alcohol, amino mercaptan, amino acid, and a compound in which these amino groups are blocked.

Examples of the diamine include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, isophoronediamine, etc.) ); And aliphatic diamines (such as ethylene diamine, tetramethylene diamine, and hexamethylene diamine).
Examples of the trivalent or higher polyamine include diethylene triamine and triethylene tetramine.
Examples of the amino alcohol include ethanolamine and hydroxyethylaniline.
Amino mercaptans include aminoethyl mercaptan, aminopropyl mercaptan and the like.
Amino acids include aminopropionic acid, aminocaproic acid and the like.
Examples of those in which these amino groups are blocked include ketimine compounds obtained from amine compounds such as diamines, triamine or higher polyamines, amino alcohols, amino mercaptans, amino acids and ketone compounds (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), Oxazoline compounds and the like.
Of these amine compounds, ketimine compounds are preferred.
The amine compound may be used alone or in combination of two or more.

The urea-modified amorphous polyester resin is treated with a terminating agent for terminating at least one of a crosslinking reaction and an elongation reaction (hereinafter also referred to as a “crosslinking / elongation reaction terminator”) to form an amorphous polyester having an isocyanate group. A resin whose molecular weight after the reaction may be adjusted by adjusting the reaction (at least one of a crosslinking reaction and an elongation reaction) between the resin (amorphous polyester prepolymer) and the amine compound.
Examples of the crosslinking / elongation reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine and the like), and those obtained by blocking them (ketimine compounds).

  The ratio of the amine compound is preferably an equivalent ratio [NCO] / [NHx] of the isocyanate group [NCO] in the amorphous polyester prepolymer having an isocyanate group and the amino group [NHx] in the amines, preferably 1 / It is 2 or more and 2/1 or less, more preferably 1 / 1.5 or more and 1.5 / 1 or less, and further preferably 1 / 1.2 or more and 1.2 / 1 or less. When [NCO] / [NHx] is in the above range, the molecular weight of the urea-modified amorphous polyester resin after the reaction increases, and it becomes easy to obtain an image in which variation in glitter is suppressed.

  The glass transition temperature of the urea-modified amorphous polyester resin is preferably from 40 ° C. to 65 ° C., more preferably from 45 ° C. to 60 ° C. The number average molecular weight is preferably 2500 or more and 50000 or less, and more preferably 2500 or more and 30000 or less. The weight average molecular weight is preferably from 10,000 to 500,000, more preferably from 30,000 to 100,000.

-Bright pigment-
Examples of the brilliant pigment include pigments (brilliant pigments) that can provide a brilliant feeling such as metallic luster. Specific examples of the glitter pigment include, for example, metal powders of aluminum (metal of Al alone), brass, bronze, nickel, stainless steel, zinc, etc .; mica coated with titanium oxide, yellow iron oxide, etc .; barium sulfate, layered silica. Flaky inorganic crystal substrate coated with silicate, layered aluminum silicate, etc .; single-crystal plate-like titanium oxide; basic carbonate; bismuth oxychloride; natural guanine; flaky glass powder; There is no particular limitation as long as it has a glittering property.
Among the glitter pigments, metal powders are preferred from the viewpoint of specular reflection intensity, and aluminum is most preferred.

The shape of the glittering pigment is flat (scale-like).
The average length of the glitter pigment in the major axis direction is preferably from 1 μm to 30 μm, more preferably from 3 μm to 20 μm, even more preferably from 5 μm to 15 μm.
The ratio (aspect ratio) of the average length in the major axis direction when the average length in the thickness direction of the glitter pigment is 1 is preferably 5 or more and 200 or less, more preferably 10 or more and 100 or less, 30 or more and 70 or less are more preferable.

  Each average length and aspect ratio of the glitter pigment is measured by the following method. Using a scanning electron microscope (S-4800, manufactured by Hitachi High-Technologies Corporation), a photograph of the pigment particles was taken at a measurable magnification (300 to 100,000 times), and the obtained image of the pigment particles was two-dimensionally photographed. In this state, the length of each particle in the long axis direction and the length in the thickness direction are measured, and the average length and aspect ratio in the long axis direction of the brilliant pigment are calculated.

  The content of the glitter pigment is, for example, preferably from 1 part by mass to 50 parts by mass, more preferably from 15 parts by mass to 25 parts by mass with respect to 100 parts by mass of the toner particles.

-Release agent-
Examples of the release agent include hydrocarbon wax; natural wax such as carnauba wax, rice wax and candelilla wax; synthetic or mineral / petroleum wax such as montan wax; ester wax such as fatty acid ester and montanic acid ester. And the like. The release agent is not limited to this.
The melting temperature of the release agent is preferably from 60 ° C to 100 ° C, more preferably from 60 ° C to 80 ° C, as measured by differential thermal analysis (based on ASTM D3418-8) of the release agent alone. More preferably, the temperature is 60 ° C. or more and 70 ° C. or less.
By setting the melting temperature of the release agent alone to the above range, the endothermic peak of the release agent falls within the range of 60 ° C. or more and 100 ° C. or less in the second heating process in the endothermic / exothermic curve of the differential thermal analysis of the toner particles. Is easily obtained.

The content of the release agent is, for example, preferably from 1% by mass to 20% by mass, more preferably from 5% by mass to 15% by mass, based on the whole toner particles.
The mixing ratio of the release agent and the crystalline resin is, for example, from 1: 1 to 1: 3 in terms of mass ratio, from the viewpoint of obtaining an image in which the variation in glitter that occurs when the image is fixed at high speed and at low temperature is suppressed. It is preferable that it is within the range.

-Other additives-
Examples of the other additives include well-known additives such as a magnetic material, a charge control agent, inorganic particles, and other coloring agents other than the glitter pigment. These additives are contained in the toner particles as internal additives.

  Examples of the charge control agent include a quaternary ammonium salt compound, a nigrosine compound, a dye containing a complex of aluminum, iron, and chromium, and a triphenylmethane pigment.

  As the inorganic particles, for example, known inorganic particles such as silica particles, titanium oxide particles, alumina particles, cerium oxide particles, or those obtained by subjecting their surfaces to a hydrophobic treatment may be used alone or in combination of two or more. Good. Among these, silica particles having a refractive index smaller than that of the binder resin are preferably used. The silica particles may be subjected to various surface treatments. For example, those subjected to a surface treatment with a silane coupling agent, a titanium coupling agent, silicone oil, or the like are preferably used.

  Other coloring agents other than the glitter pigment include known coloring agents, which are selected according to the desired color. As the other colorant, a colorant having been subjected to a surface treatment as necessary may be used, or may be used in combination with a dispersant.

-Characteristics of toner particles-
The toner particles may be toner particles having a single-layer structure, or toner particles having a so-called core-shell structure composed of a core (core particle) and a coating layer (shell layer) covering the core. May be.
The toner particles having a core-shell structure include, for example, a core portion containing a brilliant pigment, a binder resin, and if necessary, other additives such as a release agent, and a coating layer containing a binder resin. Good to be.

・ Average maximum thickness C and average equivalent circle diameter D of toner particles
It is preferable that the toner particles have a flat shape and the average circle equivalent diameter D is longer than the average maximum thickness C. The ratio (C / D) of the average maximum thickness C to the average equivalent circle diameter D (C / D) is more preferably in the range of 0.001 to 0.500, and further preferably in the range of 0.010 to 0.200. The range of 0.050 or more and 0.100 or less is particularly preferable.
When the ratio (C / D) is 0.001 or more, the strength of the toner is ensured, breakage due to stress during image formation is suppressed, charge is reduced due to exposure of the pigment, and fog generated as a result. Is suppressed. On the other hand, when it is 0.500 or less, excellent glitter is obtained.

The above average maximum thickness C and average circle equivalent diameter D are measured by the following method.
The toner particles are placed on a smooth surface, and dispersed by applying vibrations so as to have no unevenness. For 1000 toner particles, the maximum thickness C of the glitter toner particles and the equivalent circle diameter D of the surface viewed from above are measured with a color laser microscope “VK-9700” (manufactured by Keyence Corporation) at a magnification of 1000 times. Then, they are calculated by calculating their arithmetic average values.

The angle between the long axis direction and the long axis direction of the glitter pigment in the cross section of the toner particles. When the cross section in the thickness direction of the toner particles is observed, the long axis direction in the cross section of the toner particles and the length of the glitter pigment It is preferable that the proportion (number basis) of the glitter pigment whose angle with the axial direction is in the range of −30 ° to + 30 ° is 60% or more of the total glitter pigment observed. Further, the ratio is more preferably 70% or more and 95% or less, and particularly preferably 80% or more and 90% or less.
When the ratio is 60% or more, excellent glitter can be obtained.

Here, a method for observing the cross section of the toner particles will be described.
After embedding the toner particles using a bisphenol A type liquid epoxy resin and a curing agent, a cutting sample is prepared. Next, the cutting sample is cut at −100 ° C. using a cutting machine using a diamond knife, for example, an ultramicrotome apparatus (UltracutUCT, manufactured by Leica) to prepare an observation sample. The observation sample is observed with an ultra-high resolution field emission scanning electron microscope (S-4800, manufactured by Hitachi High-Technologies Corporation) at a magnification at which about 1 to 10 toner particles can be seen in one visual field.
Specifically, a cross section of the toner particles (a cross section along the thickness direction of the toner particles) was observed, and for the observed 100 toner particles, the major axis direction in the cross section of the toner particles and the major axis direction of the glitter pigment The number of the brilliant pigments having an angle of from −30 ° to + 30 ° is determined using, for example, image analysis software such as Mitani Corporation's image analysis software (Wim ROOF) or an output sample of the observed image and a protractor. Count and calculate the percentage.

  The “long axis direction in the cross section of the toner particles” refers to a direction perpendicular to the thickness direction of the toner particles having an average equivalent circle diameter D longer than the average maximum thickness C described above. "Long axis direction" refers to the length direction of the glitter pigment.

  The volume average particle diameter of the toner particles is preferably from 1 μm to 30 μm, more preferably from 3 μm to 20 μm.

The volume average particle diameter _D50v of the toner particles is defined as a volume and a number with respect to a particle size range (channel) divided based on a particle size distribution measured by a measuring device such as Multisizer II (manufactured by Coulter Inc.). Each is obtained by drawing a cumulative distribution from the smaller diameter side. The particle diameter at which the accumulation is 16% is defined as volume D _16v and number D _16p , and the particle diameter at which accumulation is 50% is _defined as volume D _50v , number D _50p and the particle diameter at which accumulation is 84% is defined as volume D _84v and number D _84p . . Using these, the volume average particle size distribution index (GSDv) is calculated as ( _D84v / _D16v ) ^1/2 .

(External additives)
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. SiO ₂ , K ₂ O. (TiO ₂ ) n, Al ₂ O ₃ .2SiO ₂ , CaCO ₃ , MgCO ₃ , BaSO ₄ , MgSO _{4 and the} like.

The surface of the inorganic particles as an external additive is preferably subjected to a hydrophobic treatment. The hydrophobic treatment is performed, for example, by immersing the inorganic particles in a hydrophobic treatment agent. The hydrophobizing agent is not particularly limited, and examples thereof include a silane coupling agent, a silicone oil, a titanate coupling agent, and an aluminum 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 based on 100 parts by mass of the inorganic particles.

  Examples of the external additive include resin particles (resin particles such as polystyrene, polymethyl methacrylate (PMMA), and melamine resin), a cleaning activator (for example, a metal salt of a higher fatty acid represented by zinc stearate, a fluoropolymer, Particles).

  The external additive amount of the external additive is, for example, preferably from 0.01% by mass to 5% by mass, more preferably from 0.01% by mass to 2.0% by mass, based on the toner particles.

(Toner manufacturing method)
Next, a method for manufacturing the toner according to the exemplary embodiment will be described.
The toner according to the exemplary embodiment is obtained by externally adding an external additive to the toner particles after manufacturing the toner particles containing the glitter pigment.

  The toner particles may be produced by any of a dry production method (for example, a kneading and pulverizing method) and a wet production method (for example, an aggregation and coalescence method, a suspension polymerization method, and a dissolution suspension method). The method for producing the toner particles is not particularly limited, and a well-known method is employed.

For example, the dissolution suspension method contains a particle dispersant by dissolving or dispersing a raw material (eg, resin particles and glitter pigment) constituting toner particles in an organic solvent in which a binder resin can be dissolved. This is a method in which toner particles are obtained by dispersing in an aqueous solvent and then removing the organic solvent to granulate the toner particles.
In addition, the emulsion aggregation method is a method of obtaining toner particles through an aggregation step of forming an aggregate of raw materials (such as resin particles and a brilliant pigment) constituting toner particles and a fusion step of fusing the aggregates. .

  Among these, toner particles containing a urea-modified amorphous polyester resin as a binder resin are preferably obtained by a solution suspension method described below. In the following description of the dissolution suspension method, as a binder resin, an unmodified polyester resin (including both a crystalline polyester resin and an amorphous polyester resin; the same applies hereinafter) and a urea-modified amorphous polyester are used. A method for obtaining resin-containing toner particles will be described.

[Oil phase liquid preparation step]
An oil phase liquid is prepared by dissolving or dispersing a toner particle material containing an unmodified polyester resin, an amorphous polyester prepolymer having an isocyanate group, an amine compound, a glitter pigment, and a release agent in an organic solvent (oil Phase liquid preparation step). In this oil phase liquid preparation step, the toner particle material is dissolved or dispersed in an organic solvent to obtain a mixed liquid of the toner material.

  The oil phase liquid is prepared by: 1) a method of preparing by dissolving or dispersing the toner material in a lump in an organic solvent and 2) kneading the toner material in advance and then dissolving or dispersing the kneaded product in the organic solvent. 3) dissolving an unmodified polyester resin, an amorphous polyester prepolymer having an isocyanate group, and an amine compound in an organic solvent, and then dispersing a glitter pigment and a release agent in the organic solvent. 4) After dispersing the glitter pigment and the release agent in an organic solvent, an unmodified polyester resin, an amorphous polyester prepolymer having an isocyanate group, and an amine compound are dissolved in the organic solvent. 5) Non-crystalline polyester prepolymer having isocyanate group and toner particle material other than amine compound (unmodified polyester resin, glitter And a mold release agent) in an organic solvent, and then dissolving an amorphous polyester prepolymer having an isocyanate group and an amine compound in the organic solvent. 6) Having an isocyanate group After dissolving or dispersing toner particle materials (unmodified polyester resin, glitter pigment, and release agent) other than the amorphous polyester prepolymer or amine compound in an organic solvent, the organic solvent has an isocyanate group. Examples thereof include a method of dissolving and preparing an amorphous polyester prepolymer or an amine compound. The method for preparing the oil phase liquid is not limited to these.

  Examples of the organic solvent of the oil phase liquid include ester solvents such as methyl acetate and ethyl acetate; ketone solvents such as methyl ethyl ketone and methyl isopropyl ketone; aliphatic hydrocarbon solvents such as hexane and cyclohexane; dichloromethane, chloroform, trichloroethylene and the like. Halogenated hydrocarbon solvents and the like can be mentioned. These organic solvents dissolve the binder resin, and dissolve in water in an amount of about 0% to 30% by mass, and preferably have a boiling point of 100 ° C. or less. Among these organic solvents, ethyl acetate is preferred.

[Suspension preparation step]
Next, the obtained oil phase liquid is dispersed in the aqueous phase liquid to prepare a suspension (suspension preparing step).
Then, together with the preparation of the suspension, the amorphous polyester prepolymer having an isocyanate group is reacted with the amine compound. This reaction produces a urea-modified amorphous polyester resin. This reaction involves at least one of a crosslinking reaction and an elongation reaction of a molecular chain. The reaction between the amorphous polyester prepolymer having an isocyanate group and the amine compound may be performed together with an organic solvent removing step described later.
Here, the reaction conditions are selected according to the reactivity between the isocyanate group structure of the amorphous polyester prepolymer and the amine compound. As an example, the reaction time is preferably from 10 minutes to 40 hours, and more preferably from 2 hours to 24 hours. The reaction temperature is preferably from 0 ° C to 150 ° C, more preferably from 40 ° C to 98 ° C. A known catalyst (dibutyltin laurate, dioctyltin laurate, etc.) may be used, if necessary, for producing the urea-modified amorphous polyester resin. That is, the catalyst may be added to the oil phase liquid or the suspension.

  Examples of the aqueous phase liquid include an aqueous phase liquid in which a particle dispersant such as an organic particle dispersant or an inorganic particle dispersant is dispersed in an aqueous solvent. Examples of the aqueous phase liquid include an aqueous phase liquid in which a particle dispersant is dispersed in an aqueous solvent and a polymer dispersant is dissolved in the aqueous solvent. Note that a well-known additive such as a surfactant may be added to the aqueous phase liquid.

  The aqueous solvent includes water (for example, usually, ion-exchanged water, distilled water, and pure water). The aqueous solvent is a solvent containing water and an organic solvent such as alcohol (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methylcellosolve, etc.), and lower ketones (acetone, methylethylketone, etc.). There may be.

  Examples of the organic particle dispersant include hydrophilic organic particle dispersants. Examples of the organic particle dispersant include particles of a poly (meth) acrylic acid alkyl ester resin (for example, polymethyl methacrylate resin), a polystyrene resin, and a poly (styrene-acrylonitrile) resin. Examples of the organic particle dispersant include styrene acrylic resin particles.

  Examples of the inorganic particle dispersant include hydrophilic inorganic particle dispersants. Specific examples of the inorganic particle dispersant include particles of silica, alumina, titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, clay, diatomaceous earth, bentonite, etc., and calcium carbonate particles are preferred. One type of inorganic particle dispersant may be used alone, or two or more types may be used in combination.

The surface of the particle dispersant may be surface-treated with a polymer having a carboxyl group.
Examples of the polymer having a carboxyl group include a carboxyl group of an α, β-monoethylenically unsaturated carboxylic acid or an α, β-monoethylenically unsaturated carboxylic acid formed of an alkali metal, an alkaline earth metal, ammonium, an amine, or the like. A copolymer of at least one selected from neutralized salts (alkali metal salts, alkaline earth metal salts, ammonium salts, amine salts, etc.) and an α, β-monoethylenically unsaturated carboxylic acid ester is exemplified. Can be Examples of the polymer having a carboxyl group include a carboxyl group of a copolymer of an α, β-monoethylenically unsaturated carboxylic acid and an α, β-monoethylenically unsaturated carboxylic acid ester in which an alkali metal or an alkaline earth metal is used. And salts neutralized with ammonium, an amine or the like (alkali metal salt, alkaline earth metal salt, ammonium salt, amine salt, etc.). As the polymer having a carboxyl group, one type may be used alone, or two or more types may be used in combination.

  Representative examples of α, β-monoethylenically unsaturated carboxylic acids include α, β-unsaturated monocarboxylic acids (acrylic acid, methacrylic acid, crotonic acid, etc.) and α, β-unsaturated dicarboxylic acids (maleic acid). Acid, fumaric acid, itaconic acid and the like). Representative examples of the α, β-monoethylenically unsaturated carboxylic acid ester include (meth) acrylic acid alkyl esters, (meth) acrylate having an alkoxy group, (meth) acrylate having a cyclohexyl group, Examples thereof include (meth) acrylates having a hydroxy group, and polyalkylene glycol mono (meth) acrylates.

  Examples of the polymer dispersant include a hydrophilic polymer dispersant. As the polymer dispersant, specifically, a polymer dispersant having a carboxyl group and not having a lipophilic group (hydroxypropoxy group, methoxy group, etc.) (for example, a water-soluble agent such as carboxymethylcellulose, carboxyethylcellulose, etc.) Cellulose ether).

[Solvent removal step]
Next, the organic solvent is removed from the obtained suspension to obtain a toner particle dispersion (solvent removal step). In the solvent removing step, the organic solvent contained in the droplets of the aqueous phase liquid dispersed in the suspension is removed to generate toner particles. The removal of the organic solvent from the suspension may be performed immediately after the suspension preparation step, or may be performed one minute or more after the suspension preparation step.
In the solvent removing step, the organic solvent is preferably removed from the suspension by cooling or heating the obtained suspension to, for example, a temperature range of 0 ° C. or more and 100 ° C. or less.

Specific methods for removing the organic solvent include the following methods.
(1) A method of forcibly renewing the gas phase on the suspension surface by blowing an air stream on the suspension. In this case, a gas may be blown into the suspension.
(2) A method of reducing pressure. In this case, the gas phase on the suspension surface may be forcibly renewed by gas filling, or gas may be blown into the suspension.

Through the above steps, toner particles are obtained.
Here, after the completion of the solvent removing step, the toner particles formed in the toner particle dispersion are subjected to a known washing step, solid-liquid separation step, and drying step to obtain dried toner particles.
In the washing step, it is preferable to sufficiently perform replacement washing with ion-exchanged water from the viewpoint of chargeability.
The solid-liquid separation step is not particularly limited, but is preferably performed by suction filtration, pressure filtration, or the like from the viewpoint of productivity. The drying step is not particularly limited, but freeze drying, flash jet drying, fluidized drying, vibration type fluidized drying and the like are preferably performed from the viewpoint of productivity.

The toner according to the exemplary embodiment is manufactured by, for example, adding and mixing an external additive to the obtained dry toner particles.
The mixing may be performed by, for example, a V blender, a Henschel mixer, a Loedige mixer, or the like.
Further, if necessary, coarse particles of the toner may be removed by using a vibration sieving machine, a wind sieving machine, or the like.

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

The carrier is not particularly limited, and includes known carriers. Examples of the carrier include a coated carrier obtained by coating a resin on the surface of a core material made of a magnetic powder; a magnetic powder-dispersed carrier in which a magnetic powder is dispersed and mixed in a matrix resin; a porous magnetic powder impregnated with a resin And a resin-impregnated carrier.
The magnetic powder-dispersed carrier and the resin-impregnated carrier may be carriers in which the constituent particles of the carrier are used as a core material and the surface thereof is coated with a resin.

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

Examples of the resin for coating and the matrix resin include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, and styrene-acryl. Examples thereof include an acid copolymer, a straight silicone resin containing an organosiloxane bond or a modified product thereof, a fluororesin, a polyester, a polycarbonate, a phenol resin, and an epoxy resin. The coating resin and the matrix resin may contain additives such as conductive particles.
Examples of the conductive particles include metals such as gold, silver, and copper; particles such as carbon black, titanium oxide, zinc oxide, tin oxide, barium sulfate, aluminum borate, and potassium titanate;

  In order to coat the surface of the core material with a resin, a method of coating with a coating layer forming solution obtained by dissolving a resin for coating and various additives (used as necessary) in an appropriate solvent may be mentioned. The solvent is not particularly limited, and may be selected in consideration of the type of resin used, suitability for application, and the like. Specific resin coating methods include a dipping method in which a core material is dipped in a solution for forming a coating layer; a spray method in which a solution for forming a coating layer is sprayed on the surface of the core material; and a state in which the core material is suspended by flowing air. A fluidized bed method of spraying a solution for forming a coating layer; a kneader coater method of mixing a core material of a carrier and a solution for forming a coating layer in a kneader coater and then removing the solvent.

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

<Image forming apparatus / image forming method>
An image forming apparatus / image forming method according to the present embodiment will be described.
The image forming apparatus according to the present exemplary embodiment includes an image carrier, a charging unit configured to charge a surface of the image carrier, an electrostatic image forming unit configured to form an electrostatic image on the charged surface of the image carrier, Developing means for containing an image developer and developing the electrostatic image formed on the surface of the image carrier as a toner image with the electrostatic image developer, and a recording medium for transferring the toner image formed on the surface of the image carrier And a fixing unit for fixing the toner image transferred to the surface of the recording medium.
The electrostatic image developer according to the exemplary embodiment is applied as the electrostatic image developer.

  In the image forming apparatus according to the present embodiment, the charging step of charging the surface of the image holding member, the electrostatic image forming step of forming an electrostatic image on the charged surface of the image holding member, and the electrostatic charge according to the present embodiment A developing step of developing the electrostatic image formed on the surface of the image holding member as a toner image with an image developer, and a transferring step of transferring the toner image formed on the surface of the image holding member to the surface of the recording medium, An image forming method (an image forming method according to the present embodiment) including a fixing step of fixing the toner image transferred to the surface of the recording medium is performed.

The image forming apparatus according to the present embodiment is an apparatus of a direct transfer system that directly transfers a toner image formed on the surface of an image carrier to a recording medium; An intermediate transfer type device that performs primary transfer on the surface and secondarily transfers the toner image transferred on the surface of the intermediate transfer body to the surface of the recording medium; after the transfer of the toner image, the surface of the image carrier before charging is cleaned. Apparatus provided with cleaning means; a known image forming apparatus such as an apparatus provided with a charge removing means for irradiating the surface of the image holding member with charge removing light to remove the charge after the transfer of the toner image and before charging is applied.
In the case of an intermediate transfer type apparatus, the transfer unit includes, for example, an intermediate transfer body on which a toner image is transferred on the surface, and a primary transfer for primarily transferring the toner image formed on the surface of the image holding body to the surface of the intermediate transfer body. And a secondary transfer unit for secondary-transferring the toner image transferred on the surface of the intermediate transfer member to the surface of the recording medium.

  In the image forming apparatus according to the present embodiment, for example, a portion including the developing unit may have a cartridge structure (process cartridge) that is detachably attached to the image forming apparatus. As the process cartridge, for example, a process cartridge that contains the electrostatic image developer according to the exemplary embodiment and includes a developing unit 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. The main parts shown in the figure will be described, and the description of the other parts will be omitted.
FIG. 2 is a schematic configuration diagram illustrating an embodiment of an image forming apparatus including a developing device to which the electrostatic image developer according to the present embodiment is applied.
In FIG. 1, the image forming apparatus according to the present embodiment includes a photosensitive drum 20 as an image holding member that rotates in a predetermined direction, and the photosensitive drum 20 is charged around the photosensitive drum 20. Charging device 21, an exposure device 22 as an electrostatic image forming device for forming an electrostatic image Z on the photosensitive drum 20, and a visible image from the electrostatic image Z formed on the photosensitive drum 20. Developing device 30, a transfer device 24 for transferring a toner image visualized on the photosensitive drum 20 to a recording paper 28 as a recording medium, and a cleaning device for cleaning residual toner on the photosensitive drum 20 25 are sequentially arranged.

In the present embodiment, as shown in FIG. 2, the developing device 30 has a developing housing 31 in which a developer G containing a toner 40 is accommodated. A developing roll (developing electrode) 33 as a toner holding member is disposed facing the developing opening 32, and a predetermined developing bias is applied to the developing roll 33. A developing electric field is formed in a region (developing region) between the photosensitive drum 20 and the developing roll 33. Further, a charge injection roll (injection electrode) 34 as a charge injection member is provided in the development housing 31 so as to face the development roll 33. In particular, in the present embodiment, the charge injection roll 34 also serves as a toner supply roll for supplying the toner 40 to the development roll 33.
Here, the rotation direction of the charge injection roll 34 may be selected. However, in consideration of the toner supply property and the charge injection characteristic, the charge injection roll 34 is in the same direction as the charge roll 34 at the portion facing the development roll 33. In addition, it is preferable that the toner 40 is rotated with a peripheral speed difference (for example, 1.5 times or more) to sandwich the toner 40 in a region sandwiched between the charge injection roll 34 and the developing roll 33 and to inject a charge while rubbing.

Next, the operation of the image forming apparatus according to the embodiment will be described.
When the image forming process is started, first, the surface of the photosensitive drum 20 is charged by the charging device 21, the exposure device 22 writes the electrostatic charge image Z on the charged photosensitive drum 20, and the developing device 30 The charge image Z is visualized as a toner image. Thereafter, the toner image on the photoconductor drum 20 is conveyed to a transfer portion, and the transfer device 24 electrostatically transfers the toner image on the photoconductor drum 20 to recording paper 28 as a recording medium. The residual toner on the photosensitive drum 20 is cleaned by the cleaning device 25. Thereafter, the toner image on the recording paper 28 is fixed by the fixing device 36 including the fixing member 36A (fixing belt, fixing roll, etc.) and the pressing member 36B, and an image is obtained.

<Process cartridge / Toner cartridge>
The process cartridge according to the present embodiment will be described.
The process cartridge according to the exemplary embodiment stores the electrostatic image developer according to the exemplary embodiment, and develops the electrostatic image formed on the surface of the image holding member as a toner image by the electrostatic image developer. And a process cartridge detachably attached to the image forming apparatus.

  The process cartridge according to the exemplary embodiment is not limited to the above-described configuration, and may include, as necessary, a developing device and other units such as an image carrier, a charging unit, an electrostatic image forming unit, and a transfer unit. And at least one selected from the group consisting of:

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

FIG. 3 is a schematic configuration diagram illustrating the process cartridge according to the present embodiment.
The process cartridge 200 shown in FIG. 3 includes, for example, a photoconductor 107 (an example of an image holding member) and a periphery of the photoconductor 107 by a housing 117 provided with a mounting rail 116 and an opening 118 for exposure. The charging roller 108 (an example of a charging unit), the developing device 111 (an example of a developing unit), and the photoconductor cleaning device 113 (an example of a cleaning unit) are integrally combined and held. I have.
In FIG. 3, reference numeral 109 denotes an exposure device (an example of an electrostatic image forming unit), 112 denotes a transfer device (an example of a transfer device), 115 denotes a fixing device (an example of a fixing device), and 300 denotes a recording sheet (an example of a recording medium). An example) is shown.

Next, the toner cartridge according to the present embodiment will be described.
The toner cartridge according to the present embodiment may be configured to house the toner according to the present embodiment and to be attached to and detached from the image forming apparatus. Note that the toner cartridge according to the present embodiment may contain at least toner, and may contain, for example, a developer depending on the mechanism of the image forming apparatus.

  The image forming apparatus shown in FIG. 2 is an image forming apparatus having a structure in which a toner cartridge (not shown) can be freely attached and detached. The developing device 30 is connected to the toner cartridge by a toner supply pipe (not shown). . When the amount of toner stored in the toner cartridge is low, the toner cartridge may be replaced.

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

(Preparation of crystalline polyester resin (1))
A heat-dried three-necked flask was charged with 45 mol parts of 1,9-nonanediol, 55 mol parts of dodecanedicarboxylic acid, and 0.05 mol parts of dibutyltin oxide as a catalyst, and then the air in the vessel was decompressed with nitrogen by a vacuum operation. Under an inert atmosphere with a gas, the mixture was stirred and refluxed at 180 ° C. for 2 hours by mechanical stirring. Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 5 hours. When the mixture became viscous, the mixture was air-cooled, the reaction was stopped, and a crystalline polyester resin (1) was synthesized. The weight average molecular weight (Mw) of the obtained crystalline polyester resin (1) was measured by gel permeation chromatography (in terms of polystyrene) and found to be 25,000.

(Preparation of crystalline polyester resin (2))
A crystalline polyester resin (2) was prepared in the same manner as the crystalline polyester resin (1), except that the monomer component was changed to: dimethyl sebacate: 45 parts, 1,10-decanediol: 30 parts, and dimethyl sulfoxide: 25 parts. Got. The weight average molecular weight (Mw) of the obtained crystalline polyester resin (2) was measured by gel permeation chromatography (in terms of polystyrene) and found to be 18,000.

(Preparation of crystalline polyester resin (3))
The crystalline polyester resin (3) was prepared in the same manner as the crystalline polyester resin (1), except that the monomer component was changed to 45 parts of terephthalic acid, 30 parts of 1,9-nonanediol, and 25 parts of dimethyl sulfoxide. Obtained. The weight average molecular weight (Mw) of the obtained crystalline polyester resin (3) was measured by gel permeation chromatography (in terms of polystyrene) and found to be 22,000.

(Preparation of amorphous polyester resin (1))
-Terephthalic acid: 1243 parts-Bisphenol A ethylene oxide adduct: 1830 parts-Bisphenol A propylene oxide adduct: 840 parts After heating and mixing the above components at 180 ° C, adding 3 parts of dibutyltin oxide and heating at 220 ° C. While removing water, an unmodified amorphous polyester resin was obtained. The glass transition temperature Tg of the obtained unmodified amorphous polyester resin was 60 ° C., the acid value was 3 mg KOH / g, and the hydroxyl value was 1 mg KOH / g.

(Preparation of amorphous polyester prepolymer (1))
-Terephthalic acid: 1243 parts-Bisphenol A ethylene oxide adduct: 1830 parts-Bisphenol A propylene oxide adduct: 840 parts After heating and mixing the above components at 180 ° C, adding 3 parts of dibutyltin oxide and heating at 220 ° C. While removing water, an amorphous polyester resin was obtained. 350 parts of the obtained amorphous polyester resin, 50 parts of tolylene diisocyanate, and 450 parts of ethyl acetate are put in a container, and this mixture is heated at 130 ° C. for 3 hours to obtain an amorphous polyester prepolymer (1) having an isocyanate group. (Hereinafter referred to as "isocyanate-modified amorphous polyester prepolymer (1)").

(Preparation of ketimine compound (1))
A container was charged with 50 parts of methyl ethyl ketone and 150 parts of hexamethylene diamine, and stirred at 60 ° C. to obtain a ketimine compound (1).

(Preparation of glitter pigment dispersion (1))
-Aluminum pigment (flat bright pigment, manufactured by Showa Aluminum Powder Co., Ltd., 2173EA): 100 parts-Ethyl acetate: 500 parts The above components are mixed, the mixture is filtered, and further mixed with 500 parts of ethyl acetate. Is repeated five times, and then dispersed for about 1 hour using an emulsifying and dispersing machine Cavitron (manufactured by Taiheiyo Kiko Co., Ltd., CR1010) to give a glittering pigment dispersion liquid (1) in which a glittering pigment (aluminum pigment) is dispersed. (Solid content: 10%).

(Preparation of release agent dispersion liquid (1))
-Paraffin wax (manufactured by Nippon Seiwa Co., Ltd., product number: 155): 20 parts-Amorphous polyester resin (1): 10 parts-Ethyl acetate (solvent): 100 parts After holding for a period of time, the mixture was cooled to room temperature, and dispersed for 0.5 passes using 0.5 mm zirconia beads using a bead mill (Ultra Visco Mill, manufactured by IMEX Co., Ltd.) to obtain a release agent dispersion liquid (1). Was.

(Preparation of Release Agent Dispersions (2) to (5))
According to Table 1, each release agent dispersion was obtained in the same manner as the release agent dispersion (1) except that the type of the release agent was changed.

(Preparation of oil phase liquid (1))
-Crystalline polyester resin (1): 8 parts-Amorphous polyester resin (1): 40 parts-Glitter pigment dispersion (1): 17 parts-Ethyl acetate: 56 parts 75 parts of a release agent dispersion liquid (1) was added to the mixture and stirred to obtain an oil phase liquid (1).

(Preparation of oil phase liquids (2) to (5), (C1) and (C2))
According to Table 2, each oil phase liquid was obtained in the same manner as the oil phase liquid (1) except that the type of the crystalline polyester resin, the type of the amorphous polyester resin, and the type of the release agent dispersion liquid were changed. .

(Preparation of Styrene Acrylic Resin Particle Dispersion (1))
・ Styrene: 370 parts ・ n-butyl acrylate: 30 parts ・ Acrylic acid: 4 parts ・ Dodecanethiol: 24 parts ・ Carbon tetrabromide: 4 parts A mixture obtained by mixing and dissolving the above components is mixed with a nonionic surfactant ( Dispersed in a flask in an aqueous solution in which 6 parts of Sanyo Kasei Kogyo Co., Ltd .: Nonipol 400) and 10 parts of anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) were dissolved in 560 parts of ion-exchanged water. After emulsification, an aqueous solution obtained by dissolving 4 parts of ammonium persulfate in 50 parts of ion-exchanged water was added thereto while mixing for 10 minutes, and the atmosphere was replaced with nitrogen. , And emulsion polymerization was continued for 5 hours. Thus, a styrene acrylic resin particle dispersion liquid (1) (resin particle concentration: 40% by mass) obtained by dispersing resin particles having an average particle diameter of 180 nm and a weight average molecular weight (Mw) of 15,500 was obtained. The glass transition point of the styrene acrylic resin particles was 59 ° C.

(Preparation of aqueous phase liquid (1))
・ Styrene acrylic resin particle dispersion (1): 60 parts ・ 2% aqueous solution of cellogen BS-H (Daiichi Kogyo Seiyaku Co., Ltd.): 200 parts ・ Ion-exchanged water: 200 parts Liquid (1) was obtained.

<Example 1>
-Preparation of toner particles (1)-
Oil phase liquid (1): 300 parts The above components were placed in a container, and stirred for 2 minutes with a homogenizer (Ultra Turrax: manufactured by IKA) to obtain an oil phase liquid (1P). 1) 1000 parts were added, and the mixture was stirred with a homogenizer for 20 minutes. Next, the mixture was stirred with a propeller-type stirrer at room temperature (25 ° C.) and normal pressure (1 atm) for 48 hours to remove the organic solvent, thereby forming a granular material. Next, the granules were washed with water, dried and classified to obtain toner particles (1). The volume average particle diameter of the toner particles was 12 μm.
Further, the obtained toner particles (1) were subjected to differential thermal analysis (according to ASTM D3418-8) by the method described above, and from the endothermic and exothermic curves of the differential thermal analysis obtained in the second heating process. The peak temperature of the endothermic peak based on the melting of the crystalline polyester resin was determined as the melting temperature of the crystalline resin. Similarly, the peak temperature of the endothermic peak based on the melting of the release agent was determined as the melting temperature of the release agent. Then, the difference between the melting temperature of the crystalline polyester resin and the melting temperature of the release agent was calculated. For the following toner particles (2) to (6), (C1) and (C2), the melting temperature of the crystalline resin, the melting temperature of the release agent, and the difference between these temperatures were determined in the same manner. Table 3 shows the results.

  In addition, regarding the toner particles (6), since the melting points of the crystalline resin and the release agent were close to each other, it was observed that only one peak was obtained in the thermal analysis. However, by the above-mentioned extraction method of the ethyl acetate insoluble content of the toner particles and the analysis of the compound by FT-IR, it is possible to substantially remove the material other than the crystalline resin and the release agent from the toner, and the solid matter collected on the filter paper is removed. It was confirmed that the mixture was a mixture of two kinds of a crystalline resin and a release agent.

-Preparation of glitter toner (1)-
Toner particles (1): 100 parts, hydrophobic silica (RY50, manufactured by Nippon Aerosil Co., Ltd.): 1.5 parts, and hydrophobic titanium oxide (T805, manufactured by Nippon Aerosil Co., Ltd .: T805): 1.0 part For 30 seconds at 10,000 rpm. Thereafter, the resultant was sieved with a vibration sieve having an opening of 45 μm to obtain a glittering toner (1).

<Example 2>
A toner particle (2) was obtained in the same manner as the toner particle (1), except that in preparing the toner particle (1), the oil phase liquid (1) was changed to the oil phase liquid (2).
A glitter toner (2) was obtained in the same manner as the glitter toner (1) except that the toner particles (2) were used.

<Example 3>
A toner particle (3) was obtained in the same manner as in the preparation of the toner particle (1) except that the oil phase liquid (1) was changed to the oil phase liquid (3).
A glitter toner (3) was obtained in the same manner as the glitter toner (1) except that the toner particles (3) were used.

<Example 4>
A toner particle (4) was obtained in the same manner as in the preparation of the toner particle (1) except that the oil phase liquid (1) was changed to the oil phase liquid (4).
A glitter toner (4) was obtained in the same manner as the glitter toner (1) except that the toner particles (4) were used.

<Example 5>
—Preparation of Toner Particles (5) —
-Oil phase liquid (3): 300 parts-Isocyanate-modified amorphous polyester prepolymer (1): 30 parts-Ketimine compound (1): 0.8 parts The above components are placed in a container, and a homogenizer (Ultra Turrax: After stirring for 2 minutes with IKA Co., Ltd.) to obtain an oil phase liquid (1P), 1000 parts of the aqueous phase liquid (1) was added to the vessel, followed by stirring with a homogenizer for 20 minutes. Next, the mixture was stirred with a propeller-type stirrer at room temperature (25 ° C.) and normal pressure (1 atm) for 48 hours, and the isocyanate-modified amorphous polyester prepolymer (1) and ketimine compound (1) were mixed. The reaction was performed to produce a urea-modified amorphous polyester resin, and the organic solvent was removed to form a granular material. Next, the granules were washed with water, dried and classified to obtain toner particles (5). The volume average particle diameter of the toner particles was 12 μm.

-Preparation of brilliant toner (5)-
Toner particles (5): 100 parts, hydrophobic silica (RY50, manufactured by Nippon Aerosil Co., Ltd.): 1.5 parts, and hydrophobic titanium oxide (T805, manufactured by Nippon Aerosil Co., Ltd .: 1.0 part): sample mill For 30 seconds at 10,000 rpm. Thereafter, the resultant was sieved with a vibration sieve having openings of 45 μm to obtain a brilliant toner (5).

<Example 6>
A toner particle (6) was obtained in the same manner as the toner particle (1) except that in the preparation of the toner particle (1), the oil phase liquid (1) was changed to the oil phase liquid (5).
Then, a glitter toner (6) was obtained in the same manner as the glitter toner (1) except that the toner particles (6) were used.

<Comparative Example 1>
Toner particles (C1) were obtained in the same manner as in the preparation of toner particles (1) except that the oil phase liquid (1) was changed to the oil phase liquid (C1).
Then, a glitter toner (C1) was obtained in the same manner as the glitter toner (1) except that the toner particles (C1) were used.

<Comparative Example 2>
A toner particle (C2) was obtained in the same manner as the toner particle (1), except that in preparing the toner particle (1), the oil phase liquid (1) was changed to the oil phase liquid (C2).
Then, a glitter toner (C2) was obtained in the same manner as the glitter toner (1) except that the toner particles (C2) were used.

<Measurement / Evaluation>
(Preparation of developer)
The glitter toner obtained in each example: 36 parts and the carrier: 414 parts were put in a 2 liter V blender, stirred for 20 minutes, and then sieved at 212 μm to prepare a developer. In addition, the carrier obtained by the following method was used.

-Preparation of carrier-
・ Ferrite particles (volume average particle diameter: 35 μm): 100 parts ・ Toluene: 14 parts ・ Methyl methacrylate-perfluorooctylethyl acrylate copolymer (critical surface tension: 24 dyn / cm): 1.6 parts ・ Carbon black (product) Name: VXC-72, manufactured by Cabot Corporation, volume resistivity: 100 Ωcm or less): 0.12 parts, crosslinked melamine resin particles (average particle diameter: 0.3 μm, toluene insoluble): 0.3 parts First, methyl methacrylate-par Carbon black was diluted in toluene and added to the fluorooctylethyl acrylate copolymer and dispersed in a sand mill. Next, the above components other than the ferrite particles were dispersed with a stirrer for 10 minutes to prepare a coating layer forming solution. Next, the coating layer forming solution and the ferrite particles are placed in a vacuum degassing type kneader and stirred at a temperature of 60 ° C. for 30 minutes, and then toluene is distilled off under reduced pressure to form a resin coating layer and obtain a carrier. Was.

(Evaluation)
-Brightness variation-
The obtained developer was charged into a developing device of “color 800 press remodeling machine” manufactured by Fuji Xerox Co., Ltd.
Using this remodeled machine, 100 sheets of a band-shaped solid image with a glitter toner loading of 4.5 g / m ² were output on OK top-coated paper (basis weight 127: manufactured by Oji Paper Co., Ltd.). The fixing conditions were high-speed output and low-temperature fixing, specifically, the paper conveyance speed: 400 mm / sec, and the fixing temperature: 160 ° C.

For the output first, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100th band solid images, a multi-angle colorimeter (BYK-Mac manufactured by Toyo Seiki Co., Ltd.) ), The incident light at an incident angle of −45 ° to the solid image is incident, and the reflectance A at a light receiving angle of + 30 ° and the reflectance B at a light receiving angle of −30 ° are measured. In addition, the reflectance A and the reflectance B were measured at intervals of 20 nm for light having a wavelength in the range of 400 nm to 700 nm, and the average value of the reflectance at each wavelength was obtained. From these measurement results, the ratio (X / Y) was calculated. Then, a standard deviation σ was calculated from X / Y, and the standard deviation σ was used as an index indicating a variation in glitter. The evaluation criteria are as follows. Acceptable results are A and B. Table 3 shows the results.
-Evaluation criteria-
A (○): standard deviation σ ≦ 0.5
B (△): 0.5 <standard deviation σ ≦ 1.0
C (×): 1.0 <standard deviation σ

−Hot offset−
Similarly, after changing the fixing temperature to 160 ° C., 170 ° C., 180 ° C., 190 ° C., and 200 ° C. using each developer and outputting a solid image for each sheet, immediately pass a blank sheet of paper to the fixing roll. The toner adhered to was transferred to a blank sheet, and the presence or absence of a hot offset at a level that could be visually recognized was confirmed. Acceptable results are A and B.
-Evaluation criteria-
A (○): No generation even at 200 ° C. B (Δ): Generation at 190 ° C. is acceptable but acceptable.
C (x): Generation is observed at 180 ° C or lower.

From the above results, it can be seen that in the present example, an image in which the variation in the brilliancy that occurs when fixing at a high speed and at a low temperature is suppressed can be obtained as compared with the comparative example.
Further, in the glitter toners of Examples 3 and 5 produced using the oil phase liquid (3), the toner particles containing the urea-modified amorphous polyester resin in Example 5 are the same as those of Example 3. It can be seen that the standard deviation σ indicating the variation in the brilliancy was smaller and the hot offset was suppressed as compared with Example 3 including the hydrophilic polyester resin.

2 toner particles 4 brilliant pigment 20 photoconductor drum (an example of an image carrier)
21 Charging device (an example of charging means)
22 Exposure apparatus (an example of an electrostatic image forming unit)
24 Transfer device (an example of transfer means)
25 Cleaning device (an example of cleaning means)
28,300 Recording paper (an example of a recording medium)
30 Developing device (an example of developing means)
31 developing housing 32 developing opening 33 developing roll 34 charge injection roll 36 fixing device (an example of a fixing unit)
40 Toner 107 Photoconductor (an example of an image carrier)
108 Charging roll (an example of charging means)
109 Exposure apparatus (an example of an electrostatic image forming means)
111 Developing device (an example of developing means)
112 Transfer device (an example of a transfer unit)
113 Photoconductor Cleaning Device (Example of Cleaning Means)
115 Fixing Device (Example of Fixing Means)
116 Mounting rail 117 Housing 118 Opening 200 for exposure Process cartridge

Claims (8)

It contains a flat glittering pigment, a crystalline resin, an amorphous resin, and a release agent, and in the second heating process in the endothermic / exothermic curve of the differential thermal analysis based on ASTM D3418-8, 60 In the range of not less than 100 ° C and not more than 100 ° C , the crystalline resin has at least one endothermic peak and the endothermic peak of the release agent, and the endothermic peak of the crystalline resin and the endothermic peak of the release agent. Brilliant toner having toner particles having a temperature difference of 5 ° C. or less. The glitter toner according to claim 1, wherein the difference in the temperature is 3 ° C or more and 5 ° C or less. The glitter toner according to claim 1 , wherein the toner particles include a urea-modified amorphous polyester resin as the amorphous resin. An electrostatic image developer containing the glitter toner according to claim 1 . A luminous toner according to any one of claims 1 to 3 ,
A toner cartridge that is attached to and detached from an image forming apparatus. A developing unit which contains the electrostatic image developer according to claim 4 and develops the electrostatic image formed on the surface of the image holding member as a toner image by the electrostatic image developer,
A process cartridge that is attached to and detached from the image forming apparatus. An image carrier,
Charging means for charging the surface of the image holding member,
Electrostatic image forming means for forming an electrostatic image on the surface of the charged image carrier,
A developing unit that receives the electrostatic image developer according to claim 4 and develops the electrostatic image formed on the surface of the image holding member as a toner image by the electrostatic image developer;
Transfer means for transferring the toner image formed on the surface of the image carrier to the surface of the recording medium,
Fixing means for fixing the toner image transferred to the surface of the recording medium,
An image forming apparatus comprising: A charging step of charging the surface of the image holding member,
An electrostatic image forming step of forming an electrostatic image on the surface of the charged image carrier,
A developing step of developing the electrostatic image formed on the surface of the image holding member as a toner image with the electrostatic image developer according to claim 4 ;
A transfer step of transferring the toner image formed on the surface of the image carrier to the surface of a recording medium,
A fixing step of fixing the toner image transferred to the surface of the recording medium,
An image forming method comprising: