JP6708284B2 - Toner for developing electrostatic image, electrostatic image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method - Google Patents

Description

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

Methods for visualizing image information, such as electrophotography, are currently used in various fields. In electrophotography, an electrostatic charge image is formed as image information on the surface of an image carrier by charging and forming an electrostatic charge image. Then, a toner image is formed on the surface of the image carrier with a developer containing toner, the toner image is transferred to a recording medium, and then the toner image is fixed to the recording medium. Through these steps, the image information is visualized as an image.

For example, Patent Document 1 discloses that "wax is encapsulated in the toner in the form of fine particles, the wax is entirely present from the vicinity of the surface of the toner to the inside thereof, and the wax concentration existing near the surface of the toner is the inside of the toner. A dry toner greater than the concentration of the wax present in. Further, Patent Document 1 discloses that "in a kneading and pulverizing method, an uneven distribution control resin having both a portion having a polarity close to that of a binder resin and a portion having a portion close to that of a release agent is used".

Patent Document 2 states that "the content of the wax is 3.0 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the binder resin, and the wax uneven distribution degree in the depth direction of the toner. Controlled toners' are disclosed. Further, Patent Document 2 discloses that “the position of the wax is arranged near the surface by controlling the hydrophilic/hydrophobic difference between the binder resin and the wax dissolved in a solvent”.

JP, 2004-145243, A JP, 2011-158758, A

An object of the present invention is to suppress peeling defects of a recording medium at the time of fixing, and to cause uneven glossiness of an image (hereinafter, simply referred to as “unevenness unevenness of image”) that occurs when an image is formed on a recording medium having large surface irregularities It is also intended to provide a toner for developing an electrostatic charge image.

The above problems can be solved by the following means.

<1>
Including a binder resin, a colorant, and a release agent,
A sea-island structure having a sea part containing the binder resin and an island part containing the release agent,
The mode of distribution of the uneven distribution B of the island portion including the release agent represented by the following formula (1) is 0.75 or more and 1.00 or less, and the skewness of the distribution of the uneven distribution B is -1. 10 or more and −0.50 or less,
The toner is
The first resin particle dispersion liquid in which the first resin particles serving as the binder resin are dispersed, and the colorant particle dispersion liquid in which the particles of the colorant are dispersed are mixed, and each particle in the obtained dispersion liquid is mixed. And a step of forming first aggregated particles,
After obtaining the first aggregated particle dispersion liquid in which the first aggregated particles are dispersed, the mixed dispersion liquid in which the second resin particles serving as the binder resin and the particles of the release agent are dispersed is used as the mixed dispersion liquid. While gradually increasing the concentration of the particles of the release agent therein, the particles are sequentially added to the first aggregated particle dispersion liquid to further aggregate the second resin particles and the particles of the release agent on the surface of the first aggregated particles. Then, in the step of forming the second agglomerated particles, or in the aggregating process of forming the first agglomerated particles, while gradually increasing the addition rate or increasing the concentration of the particles of the releasing agent, A step of adding a release agent particle dispersion liquid in which particles are dispersed, promoting the aggregation of each particle, and forming second aggregated particles;
Heating the second aggregated particle dispersion liquid in which the second aggregated particles are dispersed to fuse and coalesce the second aggregated particles to form toner particles;
A toner for developing an electrostatic charge image, which is a toner obtained through a process including
Formula (1): Uneven distribution B=2d/D
(In the formula (1), D represents the equivalent circle diameter (μm) of the toner in observing the cross section of the toner. d represents the distance from the center of gravity of the toner in observing the cross section of the toner to the center of gravity of the island portion including the release agent ( μm) is shown.)

<2>
The electrostatic charge image developing toner according to <1>, wherein the distribution k of the uneven distribution B is −0.20 or more and +1.50 or less.

<3>
An electrostatic charge image developer containing the electrostatic charge image developing toner according to <1> or <2>.

<4>
<1> or <2> containing the toner for developing an electrostatic charge image,
A toner cartridge that is attached to and detached from the image forming apparatus.

<5>
<3> The electrostatic charge image developer according to <3> is housed, and the electrostatic charge image developer is provided with a developing unit that develops the electrostatic charge image formed on the surface of the image carrier as a toner image,
A process cartridge that is attached to and detached from an image forming apparatus.

<6>
An image carrier,
Charging means for charging the surface of the image carrier,
Electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image carrier,
<3> a developing means for accommodating the electrostatic charge image developer, and developing the electrostatic charge image formed on the surface of the image carrier with the electrostatic charge image developer as a toner image;
Transfer means for transferring the toner image formed on the surface of the image carrier to the surface of a recording medium,
Fixing means for fixing the toner image transferred to the surface of the recording medium,
An image forming apparatus including.

<7>
A charging step of charging the surface of the image carrier,
An electrostatic charge image forming step of forming an electrostatic charge image on the surface of the charged image carrier;
A developing step of developing the electrostatic charge image formed on the surface of the image carrier as a toner image with the electrostatic charge 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 onto the surface of the recording medium,
An image forming method having:

According to the invention of <1>, the mode of the distribution of the uneven distribution B is less than 0.75, or the skewness of the distribution of the uneven distribution B is less than -1.10 or more than -0.50, Provided is a toner for developing an electrostatic charge image, which suppresses peeling failure of a recording medium during fixing and suppresses uneven gloss of an image.
According to the invention of <2>, as compared with the case where the kurtosis of the distribution of the uneven distribution B is less than −0.20 or more than +1.50, peeling failure of the recording medium at the time of fixing is suppressed and the gloss of the image is improved. A toner for developing an electrostatic charge image that suppresses unevenness is provided.

According to the invention of <3>, <4>, <5>, <6>, or <7>, the mode of the distribution of the uneven distribution degree B is less than 0.75, or the distribution of the uneven distribution degree B is distorted. Electrostatic charge image that suppresses peeling defects of the recording medium at the time of fixing and suppresses uneven gloss of the image, as compared with the case where toner for developing an electrostatic charge image having a degree of less than −0.20 or greater than −0.50 is applied. A developer, a toner cartridge, a process cartridge, an image forming apparatus, or an image forming method is provided.

FIG. 1 is a schematic configuration diagram showing an example of an image forming apparatus according to this embodiment. It is a schematic structure figure showing an example of a process cartridge concerning this embodiment. It is a schematic diagram for demonstrating the power feed addition method. FIG. 6 is a diagram showing an example of distribution of uneven distribution B of release agent domains in the toner according to the exemplary embodiment.

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

(Toner for developing electrostatic image)
The electrostatic charge image developing toner according to this exemplary embodiment (hereinafter, referred to as “toner”) includes a binder resin, a colorant, and a release agent. Further, the toner according to this exemplary embodiment has a sea-island structure having a sea part containing a binder resin and an island part containing a release agent.
Then, in this sea-island structure, the mode of the distribution of the uneven distribution B of the island portion containing the release agent represented by the formula (1) is 0.75 or more and 1.00 or less, and the distribution of the distribution of the distribution B is distorted. The degree is -1.10 or more and -0.50 or less.
Formula (1): Uneven distribution B=2d/D
(In the formula (1), D represents the equivalent circle diameter (μm) of the toner in observing the cross section of the toner. d represents the distance from the center of gravity of the toner in observing the cross section of the toner to the center of gravity of the island portion including the release agent ( μm) is shown.)

The toner according to the present exemplary embodiment, which has the above-described configuration, suppresses peeling failure of the recording medium at the time of fixing, and causes uneven image gloss (image gloss of the image when the image is formed on the recording medium having large surface irregularities). Unevenness). The reason is not clear, but it is presumed that the reason is as follows.

In recent years, there has been an increasing demand for electrophotographic image formation (hereinafter also referred to as “printing”) in the light printing market such as on-demand printing (a method of printing on demand). In this light printing market, printing that is not found in the printing market for offices or companies (so-called office printing market) is required. Specifically, printing on various types of recording media such as embossed paper, printing without a blank at the leading end of the recording medium (so-called borderless printing), and the like are required.
For this reason, in the light printing market, more characteristics than ever are required. One of the characteristics is releasability, for example. In particular, in borderless printing, image roughness is likely to occur due to peeling failure at the time of fixing the toner, and the toner is required to have releasability higher than ever.

It is known that a releasing agent is unevenly distributed in the surface layer of the toner for the purpose of improving the releasing property. The toner in which the release agent is unevenly distributed in the surface layer portion has a property that the release agent easily exudes during fixing. Therefore, the toner having this property has improved releasability.

However, when an image is formed on a recording medium having large surface irregularities such as embossed paper by a toner having a release agent unevenly distributed on the surface layer, uneven gloss of the image may occur. In a recording medium having large surface irregularities, the toner image before fixing is fixed in a state where the toner is present in each of the convex portion and the concave portion of the recording medium surface. At this time, the toner existing in the concave portions is less likely to be subjected to the fixing pressure than the toner existing in the convex portions. In other words, the toner present in the concave portions is less likely to come into contact with the fixing means (for example, the fixing member such as the fixing roll and the fixing belt) than the toner existing in the convex portions.

On the other hand, in the toner in which the release agent is unevenly distributed in the surface layer portion, the release agent oozes out even if the toner is present in the recesses where pressure is hard to receive. The release agent exuded from the toner present in the convex portion moves to the fixing means by contact with the fixing means, but the release agent from the toner present in the concave portion is hard to contact with the fixing means. It is difficult to move to, and it tends to remain in the recess. Therefore, in the image after fixing, the amount of the releasing agent remaining differs between the convex portion and the concave portion on the surface of the recording medium, and this appears as uneven gloss.

Here, the uneven distribution B of the island portion including the release agent (hereinafter, also referred to as “release agent domain”) is an index indicating how far the center of gravity of the release agent domain is from the center of gravity of the toner. .. This uneven distribution B indicates that the larger the value is, the closer the release agent domain is to the surface of the toner, and the smaller the value is, the closer the release agent domain is to the center of the toner. Then, the mode of the distribution of the uneven distribution B indicates the portion where the release agent domain is most present in the toner radial direction. On the other hand, the skewness of the distribution of the uneven distribution B indicates the bilateral symmetry of the distribution. Specifically, the skewness of the distribution of the uneven distribution B indicates the degree of tailing of the distribution from the mode. That is, the skewness of the distribution of the uneven distribution B indicates how much distribution of the release agent domain exists in the radial direction of the toner from the most abundant portion.

That is, the mode of the distribution of the uneven distribution B of the release agent domains is within the range of 0.75 or more and 1.00 or less means that the release agent domains are most present in the surface layer portion of the toner. Is shown. When the skewness of the distribution of the uneven distribution B of the release agent domain is within the range of −1.10 to −0.50, the release agent domain has a gradient from the toner surface layer portion toward the inside. Have been distributed (see FIG. 4).

As described above, in the toner in which the mode and the skewness of the distribution of the uneven distribution B of the releasing agent domain satisfy the above range, the releasing agent domain is most present in the surface layer portion, and the toner has a gradient from the inside of the toner to the surface layer portion. The toner is distributed toward the. The toner having a gradient in the distribution of the release agent domain has a property that only the release agent in the surface layer of the toner oozes out when a low pressure is applied, and the release agent inside the toner also oozes out when a high pressure is applied. That is, in the toner having the concentration gradient of the release agent domain, the amount of the release agent oozing out is controlled according to the pressure.

When an image is formed on a recording medium having large surface irregularities such as embossed paper by the toner having this property, the toner existing on the convex portion of the recording medium receives sufficient pressure at the time of fixing, so that the toner inside the toner is separated. The mold agent also oozes out and exhibits sufficient release properties. On the other hand, the toner existing in the concave portion of the recording medium is unlikely to receive pressure during fixing, and therefore only the release agent on the surface layer side of the toner seeps out. In other words, it is possible to prevent excessive release agent from seeping out in the recess.
Therefore, while exhibiting releasability at the time of fixing, in the image after fixing, the difference in the amount of the releasing agent remaining between the convex portion and the concave portion on the surface of the recording medium becomes small.

From the above, the toner according to the present embodiment suppresses peeling failure of the recording medium at the time of fixing, and causes unevenness in gloss of an image (unevenness in gloss of an image) that occurs when an image is formed on a recording medium having large surface irregularities. ) Is suppressed.

Conventionally, the difference in hydrophilicity/hydrophobicity between the binder resin dissolved in a solvent and the release agent is used to dispose the release agent in the vicinity of the surface of the toner (JP 2004-145243 A, etc.) and the binder resin. A toner (such as JP 2011-158758 A) in which the position of the release agent is located near the surface by a kneading and pulverizing method using an uneven distribution control resin having both a portion close to the polarity and a portion close to the polarity of the release agent is known. ing. However, in any of the toners, the position of the release agent in the toner is controlled by the physical properties of the material, and the distribution of the release agent domain of the toner cannot have a gradient.

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

The toner according to this exemplary embodiment has a sea-island structure having a sea part containing a binder resin and an island part containing a release agent. That is, the toner has a sea-island structure in which the release agent exists in an island shape in the continuous phase of the binder resin. It should be noted that the release agent domain is preferably not present in the central portion (center of gravity) of the toner in observing the cross section of the toner from the viewpoint of suppressing peeling defects and uneven gloss.

In the toner having a sea-island structure, the mode of distribution of the uneven distribution B of the release agent domain (island portion including the release agent) is 0.75 or more and 1.00 or less, which suppresses peeling defects and uneven gloss. From the above point, 0.80 or more and 0.95 or less are preferable, and 0.85 or more and 0.90 or less are more preferable. Particularly, from the viewpoint of the heat storage property of the toner, the mode of the distribution of the uneven distribution B of the release agent domain is preferably 0.98 or less.

The skewness of the distribution of the uneven distribution B of the release agent domain (island containing the release agent) is −1.10 or more and −0.50 or less, and from the viewpoint of suppressing gloss unevenness, −1.00 or more − 0.60 or less is preferable, and -0.95 or more and -0.65 or less is more preferable.

The kurtosis of the distribution of the uneven distribution B of the release agent domain (island containing the release agent) is preferably −0.20 or more and +1.50 or less, and −0. 15 or more and +1.40 or less are more preferable, and -0.10 or more and +1.30 or less are still more preferable.
The kurtosis is an index indicating the sharpness of the apex of the distribution of the uneven distribution B (that is, the mode of the distribution). In the distribution of the uneven distribution B, the kurtosis is in the above range, and the apex (mode) is not excessively sharp, and the distribution is appropriately curved while being sharp. For this reason, the change in the amount of release agent stains from the toner depending on the pressure becomes gentle, and the amount of release agent seepage from the toner at the convex portions and the concave portions of the recording medium tends to be appropriately maintained, resulting in peeling. Defects and uneven gloss are further suppressed.

Here, a method of confirming the sea-island structure of the toner will be described.
The sea-island structure of the toner is confirmed, for example, by observing the cross section of the toner (toner particles) with a transmission electron microscope, or by observing the cross section of the toner particles with ruthenium tetroxide and observing with a scanning electron microscope. The method of observing with a scanning electron microscope is preferable because the release agent domain in the cross section of the toner can be observed more clearly. The scanning electron microscope may be any model well known to those skilled in the art, and examples thereof include SU8020 manufactured by Hitachi High-Tech Co., Ltd. and JSM-7500F manufactured by JEOL Ltd.
The specific observation method is as follows. First, after embedding the toner (toner particles) to be measured in the epoxy resin, the epoxy resin is cured. This cured product is thinned by a microtome equipped with a diamond blade to obtain an observation sample in which the cross section of the toner is exposed. An observation sample of a thin piece is dyed with ruthenium tetroxide, and the cross section of the toner is observed with a scanning electron microscope. According to this observation method, a sea-island structure in which a release agent having a brightness difference (contrast) is present in an island shape in the continuous phase of the binder resin is observed on the cross section of the toner due to the difference in dyeing degree.

Next, a method for measuring the uneven distribution B of the release agent domain will be described.
The uneven distribution B of the release agent domain is measured as follows. First, an image is recorded at a magnification such that a cross section of one toner (toner particle) enters the field of view by using the method for confirming the sea-island structure. The recorded image is analyzed using image analysis software (WinROOF manufactured by Mitani Shoji Co., Ltd.) under the condition of 0.010000 μm/pixel. By this image analysis, the cross-sectional shape of the toner is extracted from the brightness difference (contrast) between the epoxy resin used for embedding and the binder resin of the toner. The projected area is calculated based on the shape of the extracted cross section of the toner. Then, the equivalent circle diameter is obtained from this projected area. The equivalent circle diameter is calculated by the formula: 2√(projected area/π). The calculated equivalent circle diameter is taken as the equivalent circle diameter D of the toner in observing the cross section of the toner.
On the other hand, the position of the center of gravity is obtained based on the shape of the cross section of the extracted toner. Subsequently, the shape of the release agent domain is extracted from the brightness difference (contrast) between the binder resin and the release agent, and the position of the center of gravity of the release agent domain is determined. The respective barycentric positions are, specifically, for the extracted toner or the area of the release agent domain, the number of pixels in the area is n, and the xy coordinates of each pixel are x _i and y _i (i=1). , 2,..., N), the x coordinate of the center of gravity is obtained by dividing the sum of the respective x _i coordinate values by n, and the y coordinate of the center of gravity is obtained as the value obtained by dividing the sum of the respective y _i coordinate values by n. Then, the distance between the center of gravity of the cross section of the toner and the center of gravity of the release agent domain is obtained. The obtained distance is defined as a distance d from the center of gravity of the toner in observing the cross section of the toner to the center of gravity of the island portion containing the release agent.
Finally, from the equivalent circle diameter D and the distance d, the uneven distribution B of the release agent domain is calculated by the equation (1): uneven distribution B=2d/D. Then, with respect to a plurality of release agent domains existing in the cross section of one toner (toner particle), the same operation as described above is performed to obtain the uneven distribution B of the release agent domains.

Next, a method of calculating the mode of the distribution of the uneven distribution B of the release agent domain will be described.
First, the above-described uneven distribution B of the release agent domain is measured for 200 toners (toner particles). The distribution data of the uneven distribution degree B is obtained by performing statistical analysis processing on the obtained data of the uneven distribution degree B of each release agent domain in the data interval of 0 to 0.01. The most frequent value of the obtained distribution, that is, the value of the data section that most frequently appears in the distribution of the uneven distribution B of the release agent domain is obtained. Then, the value in this data section is set as the mode of the distribution of the uneven distribution B of the release agent domain.

Next, a method of calculating the skewness of the distribution of the uneven distribution B of the release agent domain will be described.
First, as described above, the distribution of the uneven distribution B of the release agent domain is obtained. The skewness of the distribution of the uneven distribution B is calculated based on the calculated formula below. In the following equation, the skewness is Sk, the number of data of uneven distribution B of the release agent domain is n, and the value of data of uneven distribution B of each release agent domain is x _i (i=1, 2,..., n), let x be the average value of the entire data of uneven distribution B of the release agent domain (x with a bar above), and let s be the standard deviation of the entire data of uneven distribution B of the release agent domain.

Next, a method of calculating the kurtosis of the distribution of the uneven distribution B of the release agent domain will be described.
First, as described above, the distribution of the uneven distribution B of the release agent domain is obtained. The kurtosis of the distribution of the uneven distribution B is calculated based on the calculated formula below. In the following equation, the kurtosis is Ku, the number of data of uneven distribution B of the release agent domain is n, and the value of data of uneven distribution B of each release agent domain is x _i (i=1, 2,..., n), the average value of the entire data of the uneven distribution B of the release agent domain is x (x with a bar above), and the standard deviation of the entire data of uneven distribution B of the release agent domain is s

In the toner according to this exemplary embodiment, a method of satisfying the distribution characteristic of the uneven distribution B of the release agent domain will be described in the toner manufacturing method.

The constituent components of the toner according to this exemplary embodiment will be described below.
The toner according to this exemplary embodiment contains a binder resin, a colorant, and a release agent. Specifically, the toner has toner particles containing a binder resin, a colorant, and a release agent. The toner may have an external additive attached to the surface of the toner particles.

-Binder resin-
Examples of the binder resin include styrenes (eg, styrene, parachlorostyrene, α-methylstyrene, etc.), (meth)acrylic acid esters (eg, methyl acrylate, ethyl acrylate, n-propyl acrylate, acrylic acid). n-butyl, lauryl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, etc., ethylenically unsaturated nitriles (eg acrylonitrile, Methacrylonitrile etc.), vinyl ethers (eg vinyl methyl ether, vinyl isobutyl ether etc.), vinyl ketones (vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone etc.), olefins (eg ethylene, propylene, butadiene etc.) etc. The vinyl resin may be a homopolymer of the above monomer or a copolymer of two or more kinds of these monomers in combination.
As the binder resin, for example, epoxy resin, polyester resin, polyurethane resin, polyamide resin, cellulose resin, polyether resin, non-vinyl resin such as modified rosin, a mixture of these and the vinyl resin, or these A graft polymer obtained by polymerizing a vinyl-based monomer in the coexistence thereof can also be used.
These binder resins may be used alone or in combination of two or more.

A polyester resin is suitable as the binder resin.
Examples of the polyester resin include known polyester resins.

Examples of the polyester resin include polycondensates of polycarboxylic acids and polyhydric alcohols. In addition, as the polyester resin, a commercially available product or a synthesized product may be used.

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

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

The glass transition temperature (Tg) of the polyester resin is preferably 50° C. or higher and 80° C. or lower, and more preferably 50° C. or higher and 65° C. or lower.
The glass transition temperature is obtained from a DSC curve obtained by differential scanning calorimetry (DSC), and more specifically, it is described in the method for obtaining the glass transition temperature of JIS K-1987 "Plastic transition temperature measuring method". It is determined by "extrapolated glass transition onset temperature".

The polyester resin is obtained by a 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 performed while removing water and alcohol generated during the condensation.
When the raw material monomers are insoluble or incompatible at the reaction temperature, a solvent having a high boiling point may be added as a solubilizing agent and dissolved. In this case, the polycondensation reaction is carried out while distilling off the solubilizing agent. When a poorly compatible monomer is present in the copolymerization reaction, the poorly compatible monomer is condensed with the acid or alcohol to be polycondensed in advance, and then the main component and the polycondensate are mixed. It is good to condense.

The content of the binder resin is, for example, preferably 40% by mass or more and 95% by mass or less, more preferably 50% by mass or more and 90% by mass or less, and 60% by mass or more and 85% by mass or less with respect to the entire toner particles. More preferable.

-Colorant-
Examples of the colorant include carbon black, chrome yellow, Hansa yellow, benzidine yellow, thren yellow, quinoline yellow, pigment yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, permanent red, brilliant carmine 3B, brilliant. Carmine 6B, DuPont Oil Red, Pyrazolone Red, Resole Red, Rhodamine B Lake, Lake Red C, Pigment Red, Rose Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Pigment Blue, Phthalocyanine Green, Various pigments such as malachite green oxalate, or acridine, xanthene, azo, benzoquinone, azine, anthraquinone, thioindico, dioxazine, thiazine, azomethine, indico, phthalocyanine, aniline black Examples include various dyes such as system dyes, polymethine dyes, triphenylmethane dyes, diphenylmethane dyes, and thiazole dyes.
The colorants may be used alone or in combination of two or more.

The colorant may be a surface-treated colorant, if necessary, or may be used in combination with a dispersant. Further, a plurality of kinds of colorants may be used in combination.

The content of the colorant is, for example, preferably 1% by mass or more and 30% by mass or less, and more preferably 3% by mass or more and 15% by mass or less, based on the entire toner particles.

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

Among these, hydrocarbon-based wax (wax having hydrocarbon as a skeleton) is preferable as the release agent. Hydrocarbon wax is preferable because it easily forms a release agent domain and easily bleeds to the surface of the toner (toner particles) at the time of fixing.

The content of the release agent is, for example, preferably 1% by mass or more and 20% by mass or less, more preferably 5% by mass or more and 15% by mass or less, based on the entire toner particles.

-Other additives-
Examples of other additives include known additives such as magnetic materials, charge control agents, and inorganic powders. These additives are contained in the toner particles as internal additives.

-Characteristics of toner particles-
The toner particles may be toner particles having a single layer structure, or a so-called core-shell structure toner particles composed of a core portion (core particles) and a coating layer (shell layer) covering the core portion. May be.
Here, the toner particles having a core/shell structure include, for example, a core portion containing a binder resin, a colorant, and a release agent, and a coating layer containing a binder resin. It is good to have

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

Incidentally, various average particle diameters and various particle size distribution indexes of the toner particles are measured by using Coulter Multisizer II (manufactured by Beckman-Coulter) and an electrolyte solution is measured by ISOTON-II (manufactured by Beckman-Coulter). It
In the measurement, 0.5 mg or more and 50 mg or less of the measurement sample is added to 2 ml of a 5% aqueous solution of a surfactant (sodium alkylbenzenesulfonate is preferable) as a dispersant. This is added to 100 ml or more and 150 ml or less of the electrolytic solution.
The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for 1 minute, and a Coulter Multisizer II is used to obtain a particle size distribution of particles in a range of 2 μm or more and 60 μm or less using an aperture of 100 μm as an aperture diameter. taking measurement. The number of particles sampled is 50,000.
The cumulative distribution of the volume and the number is drawn from the small diameter side with respect to the particle size range (channel) divided based on the measured particle size distribution, and the cumulative particle diameter is 16% as the volume particle diameter D16v and the several particle diameters. D16p, a particle size with a cumulative 50% is defined as a volume average particle size D50v, a cumulative number average particle size D50p, and a particle size with a cumulative 84% is defined as a volume particle size D84v and a number particle size D84p.
Using these, the volume average particle size distribution index (GSDv) is calculated as (D84v/D16v) ^1/2 , and the number average particle size distribution index (GSDp) is calculated as (D84p/D16p) ^1/2 .

The shape factor SF1 of the toner particles is preferably 110 or more and 150 or less, and more preferably 120 or more and 140 or less.

The shape factor SF1 is calculated by the following equation.
Formula: SF1=(ML ² /A)×(π/4)×100
In the above formula, ML represents the absolute maximum length of the toner, and A represents the projected area of the toner.
Specifically, the shape factor SF1 is quantified mainly by analyzing a microscope image or a scanning electron microscope (SEM) image using an image analyzer, and is calculated as follows. That is, the optical microscope image of the particles scattered on the surface of the glass slide is captured by a Luzex image analyzer with a video camera, the maximum length and projected area of 100 particles are calculated, and the average value is calculated by the above formula. can get.

(External additive)
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 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the inorganic particles.

As the external additive, resin particles (polystyrene, polymethylmethacrylate (PMMA), resin particles such as melamine resin), cleaning activator (for example, metal salt of higher fatty acid typified by zinc stearate, fluorine-based polymer) Particles) and the like.

The external addition amount of the external additive is preferably 0.01% by mass or more and 5% by mass or less, and more preferably 0.01% by mass or more and 2.0% by mass or less, based on the toner particles.

(Toner manufacturing method)
Next, a method of manufacturing the toner according to this exemplary embodiment will be described.
The toner according to this exemplary embodiment is obtained by manufacturing toner particles and then externally adding an external additive to the toner particles.

The toner particles may be manufactured by either a dry manufacturing method (for example, a kneading pulverization method or the like) or a wet manufacturing method (for example, an aggregation and coalescence method, a suspension polymerization method, a dissolution suspension method or the like). The production method of toner particles is not particularly limited, and a well-known production method is used.
Among these, it is preferable to obtain the toner particles by the aggregation and coalescence method.

In particular, from the viewpoint of obtaining a toner (toner particles) that satisfies the distribution characteristics of the uneven distribution B of the release agent domain described above, the toner particles are preferably manufactured by the following aggregation and coalescence method.

Specifically, a step of preparing each dispersion (dispersion preparation step),
A first resin particle dispersion liquid in which first resin particles serving as a binder resin are dispersed, and a colorant particle dispersion liquid in which colorant particles (hereinafter also referred to as “colorant particles”) are dispersed are mixed to obtain A step of aggregating each particle in the dispersed liquid to form a first agglomerated particle (first agglomerated particle forming step),
After the first aggregated particle dispersion liquid in which the first aggregated particles are dispersed, the second resin particles serving as the binder resin and the release agent particles (hereinafter also referred to as “release agent particles”) are mixed and mixed. The dispersion liquid is sequentially added to the first aggregated particle dispersion liquid while gradually increasing the concentration of the release agent particles in the mixed dispersion liquid, and the second resin particles and the release agent particles are further added to the surface of the first aggregated particles. A step of aggregating to form second agglomerated particles (second agglomerated particle forming step),
A step of heating the second aggregated particle dispersion liquid in which the second aggregated particles are dispersed to fuse and coalesce the second aggregated particles to form toner particles (fusing/merging step);
It is preferable to manufacture the toner particles through

The method for producing toner particles is not limited to the above. For example, the resin particle dispersion liquid and the colorant particle dispersion liquid are mixed, and the respective particles are aggregated in the obtained mixed dispersion liquid. Next, in the aggregation process, the release agent particle dispersion liquid is added to the mixed dispersion liquid while gradually increasing the addition rate or increasing the concentration of the release agent particles, and further the aggregation of each particle is advanced. To form aggregated particles. Then, the aggregated particles may be fused and united to form toner particles.

The details of each step will be described below.

-Each dispersion liquid preparation step-
First, each dispersion liquid used in the aggregation and coalescence method is prepared. Specifically, a first resin particle dispersion liquid in which first resin particles serving as a binder resin are dispersed, a colorant particle dispersion liquid in which colorant particles are dispersed, and a second resin particle serving as a binder resin are dispersed. A second resin particle dispersion liquid and a release agent particle dispersion liquid in which release agent particles are dispersed are prepared.
In addition, in each dispersion liquid preparation step, the first resin particles and the second resin particles are referred to as “resin particles” in the description.

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

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

As the surfactant, for example, sulfate ester-based, sulfonate-based, phosphate ester-based, soap-based anionic surfactants; amine salt-type, quaternary ammonium salt-type, etc. cationic surfactants; polyethylene glycol Examples thereof include nonionic surfactants such as polyphenols, alkylphenol ethylene oxide adducts and polyhydric alcohols. Among these, anionic surfactants and cationic surfactants are particularly preferable. The nonionic surfactant may be used in combination with the anionic surfactant or the cationic surfactant.
The surfactants may be used alone or in combination of two or more.

Examples of the method for dispersing the resin particles in the dispersion medium in the resin particle dispersion liquid include general dispersion methods such as a rotary shear homogenizer, a ball mill having a medium, a sand mill, and a dyno mill. Further, depending on the type of resin particles, the resin particles may be dispersed in the resin particle dispersion liquid by using, for example, a phase inversion emulsification method.
The phase inversion emulsification method is to dissolve the resin to be dispersed in a hydrophobic organic solvent in which the resin is soluble, add a base to the organic continuous phase (O phase), neutralize the resin, and then add an aqueous medium. A method in which a resin is converted from W/O to O/W (so-called phase inversion) by introducing (W phase) to form a discontinuous phase, and the resin is dispersed in an aqueous medium into particles. Is.

The volume average particle diameter of the resin particles dispersed in the resin particle dispersion liquid is, for example, preferably 0.01 μm or more and 1 μm or less, more preferably 0.08 μm or more and 0.8 μm or less, and further preferably 0.1 μm or more and 0.6 μm or less. preferable.
The volume average particle size of the resin particles is the particle size distribution obtained by the measurement of a laser diffraction particle size distribution measuring device (for example, LA-700 manufactured by Horiba Ltd.), and the particle size range (channel) is divided. The cumulative distribution is subtracted from the small particle size side with respect to the volume, and the particle size at which cumulative 50% of all particles is obtained is measured as the volume average particle size D50v. The volume average particle size of the particles in the other dispersions is measured in the same manner.

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

Note that, for example, a colorant particle dispersion liquid and a release agent particle dispersion liquid are prepared in the same manner as the resin particle dispersion liquid. That is, regarding the volume average particle size of the particles in the resin particle dispersion liquid, the dispersion medium, the dispersion method, and the content of the particles, the colorant particles dispersed in the colorant particle dispersion liquid and the release agent particle dispersion liquid are The same applies to the release agent particles to be dispersed.

-First aggregated particle forming step-
Next, the first resin particle dispersion liquid and the colorant particle dispersion liquid are mixed.
Then, in this mixed dispersion liquid, the first resin particles and the colorant particles are hetero-aggregated to form first agglomerated particles containing the first resin particles and the colorant particles.

Specifically, for example, after adding a flocculant to the mixed dispersion, adjusting the pH of the mixed dispersion to acidic (for example, pH is 2 or more and 5 or less), and adding a dispersion stabilizer as necessary, Particles which are heated to a glass transition temperature of the first resin particles (specifically, for example, glass transition temperature of the first resin particles −30° C. or higher and glass transition temperature −10° C. or lower) and dispersed in the mixed dispersion liquid. Are aggregated to form first aggregated particles.
In the first agglomerated particle forming step, for example, the aggregating agent is added at room temperature (for example, 25° C.) while stirring the mixed dispersion with a rotary shear homogenizer, and the pH of the mixed dispersion is acidic (for example, pH is 2 or more). The temperature may be adjusted to 5 or less), and a dispersion stabilizer may be added if necessary, and then the above heating may be performed.

Examples of the aggregating agent include a surfactant having a polarity opposite to that of the surfactant used as the dispersant added to the mixed dispersion liquid, an inorganic metal salt, and a divalent or higher valent metal complex. In particular, when a metal complex is used as the aggregating agent, the amount of the surfactant used is reduced and the charging characteristics are improved.
If necessary, an additive which forms a complex or a similar bond with the metal ion of the aggregating agent may be used. A chelating agent is preferably used as the additive.

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

-Second aggregated particle forming step-
Next, after obtaining the first aggregated particle dispersion liquid in which the first aggregated particles are dispersed, the mixed dispersion liquid in which the second resin particles and the release agent particles are dispersed is mixed with the release agent particles in the mixed dispersion liquid. While gradually increasing the concentration, they are sequentially added to the first aggregated particle dispersion liquid.
The second resin particles may be of the same type as the first resin particles, or may be of a different type.

Then, in the dispersion liquid in which the first aggregated particles, the second resin particles, and the release agent particles are dispersed, the second resin particles and the release agent particles are aggregated on the surface of the first aggregated particles. Specifically, for example, in the first aggregated particle forming step, when the first aggregated particles reach a target particle size, the concentration of the release agent particles in the first aggregated particle dispersion liquid is gradually increased, A mixed dispersion liquid in which the second resin particles and the release agent particles are dispersed is added, and the dispersion liquid is heated at a temperature not higher than the glass transition temperature of the second resin particles.
Then, the progress of aggregation is stopped by adjusting the pH of the dispersion liquid to a range of, for example, 6.5 or more and 8.5 or less.

Through this step, aggregated particles in which the second resin particles and the release agent particles adhere to the surface of the first aggregated particles are formed. That is, the second aggregated particles in which the aggregates of the second resin particles and the release agent particles are attached to the surface of the first aggregated particles are formed. At this time, the mixed dispersion liquid in which the second resin particles and the release agent particles are dispersed is sequentially added to the first aggregated particle dispersion liquid while gradually increasing the concentration of the release agent particles in the mixed dispersion liquid. On the surface of the first agglomerated particles, the concentration (release rate) of the release agent particles gradually increases toward the outside in the particle diameter direction, and the agglomerates of the second resin particles and the release agent particles adhere.

Here, as a method for adding the mixed dispersion liquid, a power feed addition method may be used. By using this power feed addition method, the mixed dispersion can be added to the first aggregated particle dispersion while gradually increasing the concentration of the release agent particles in the mixed dispersion.

Hereinafter, a method of adding the mixed dispersion liquid using the power feed addition method will be described with reference to the drawings.

FIG. 3 shows an apparatus used for the power feed addition method. In FIG. 3, 311 represents the first aggregated particle dispersion, 312 represents the second resin particle dispersion, and 313 represents the release agent particle dispersion.

The apparatus shown in FIG. 3 contains a first storage tank 321 in which the first aggregated particles are dispersed to store the first aggregated particle dispersion liquid, and a second resin particle dispersion liquid in which the second resin particles are dispersed. The second storage tank 322 is provided with a second storage tank 322, and the third storage tank 323 is provided with a release agent particle dispersion liquid in which the release agent particles are dispersed.

The first storage tank 321 and the second storage tank 322 are connected by a first liquid feed pipe 331. A first liquid feed pump 341 is interposed in the middle of the path of the first liquid feed pipe 331. By driving the first liquid feed pump 341, the dispersion liquid stored in the second storage tank 322 is transferred to the dispersion liquid stored in the first storage tank 321 through the first liquid transfer pipe 331.
A first stirring device 351 is arranged in the first storage tank 321. When the dispersion liquid stored in the second storage tank 322 is sent to the dispersion liquid stored in the first storage tank 321 by driving the first stirring device 351, each dispersion liquid is stirred and stirred in the first storage tank 321. Mixed.

The second storage tank 322 and the third storage tank 323 are connected by the second liquid supply pipe 332. A second liquid feed pump 342 is provided in the middle of the path of the second liquid feed pipe 332. By driving the second liquid feed pump 342, the dispersion liquid stored in the third storage tank 323 is transferred to the dispersion liquid stored in the second storage tank 322 through the second liquid transfer pipe 332.
A second stirring device 352 is arranged in the second storage tank 322. When the dispersion liquid stored in the third storage tank 323 is sent to the dispersion liquid stored in the second storage tank 322 by driving the second stirring device 352, each dispersion liquid is stirred and stirred in the second storage tank 322. Mixed.

In the apparatus shown in FIG. 3, first, in the first storage tank 321, the first aggregated particle forming step is performed to prepare the first aggregated particle dispersion liquid, and the first aggregated particle dispersion liquid is placed in the first storage tank 321. Accommodate. The first aggregated particle dispersion process may be performed in another tank to prepare the first aggregated particle dispersion liquid, and then the first aggregated particle dispersion liquid may be stored in the first storage tank 321.

In this state, the first liquid feed pump 341 and the second liquid feed pump 342 are driven. By this driving, the second resin particle dispersion liquid stored in the second storage tank 322 is sent to the first aggregated particle dispersion liquid stored in the first storage tank 321. Then, by driving the first stirring device 351, each dispersion liquid is stirred and mixed in the first storage tank 321.
On the other hand, the release agent particle dispersion liquid stored in the third storage tank 323 is sent to the second resin particle dispersion liquid stored in the second storage tank 322. Then, by driving the second stirring device 352, each dispersion liquid is stirred and mixed in the second storage tank 322.

At this time, the release agent particle dispersion liquid is sequentially fed to the second resin particle dispersion liquid stored in the second storage tank 322, and the concentration of the release agent particles gradually increases. Therefore, the second storage tank 322 contains the mixed dispersion liquid in which the second resin particles and the release agent particles are dispersed, and this mixed dispersion liquid is stored in the first storage tank 321. 1 Agglomerated particle dispersion is sent. Then, the feeding of the mixed dispersion is continuously performed while the concentration of the release agent particle dispersion in the mixed dispersion is increased.

As described above, by using the power feed addition method, the mixed dispersion liquid in which the second resin particles and the release agent particles are dispersed while gradually increasing the concentration of the release agent particles is added to the first aggregated particle dispersion liquid. It can be added.
Then, in the power feed addition method, the distribution characteristic of the release agent domain of the toner is adjusted by adjusting the liquid feed start timing and liquid feed speed of each dispersion liquid stored in the second storage tank 322 and the third storage tank 323. Is adjusted. Further, in the power feed addition method, the distribution of the toner releasing agent domain can also be obtained by adjusting the liquid sending speed during the liquid sending of the dispersion liquids stored in the second storage tank 322 and the third storage tank 323. The characteristics are adjusted.

Specifically, for example, the mode of the distribution of the uneven distribution B of the release agent domain is adjusted by the time when the release agent particle dispersion liquid is completely sent from the third storage tank 323 to the second storage tank 322. It More specifically, for example, before the completion of the liquid transfer from the second storage tank 322 to the first storage tank 321, the transfer of the release agent particle dispersion liquid from the third storage tank 323 to the second storage tank 322. After that, the concentration of the release agent particles in the mixed dispersion liquid in the second storage tank 322 does not rise beyond that point. As a result, the mode of the distribution of the uneven distribution B of the release agent domain becomes small.

Further, for example, the skewness of the distribution of the uneven distribution B of the release agent domain is determined by the timing of sending each dispersion liquid from the second storage tank 322 and the third storage tank 323 and the second storage tank 322 to the first storage tank. It is adjusted by the liquid sending speed of sending the dispersion liquid to 321. More specifically, for example, the delivery start timing of the release agent particle dispersion liquid from the third storage tank 323 and the delivery start timing of the dispersion liquid from the second storage tank 322 are advanced so that When the liquid-feeding speed of the dispersion liquid is reduced, the releasing agent particles are arranged from the inner side to the outer side of the formed aggregated particles. As a result, the skewness of the distribution of the uneven distribution B of the release agent domain becomes large.

Further, for example, the kurtosis of the distribution of the uneven distribution B of the release agent domain is adjusted by changing the liquid feeding speed of the release agent particle dispersion liquid from the third storage tank 323 during the liquid feeding. More specifically, for example, when the release agent particle dispersion liquid is being fed from the third storage tank 323 and only the liquid feeding speed is increased, the release of the dispersion liquid in the second storage tank 322 from that point onward is released. The concentration of drug particles increases. Therefore, in the formed agglomerated particles, many release agent particles are arranged in a certain region (a certain depth portion) in the radial direction of the particles. This increases the kurtosis of the distribution of the uneven distribution B of the release agent domain.

The power feed addition method described above is not limited to the above method. For example, 1) separately providing a storage tank for storing the second resin particle dispersion liquid and a storage tank for the mixed dispersion liquid in which the second resin particles and the release agent particle dispersion liquid are dispersed, while changing the liquid feeding speed. Method of sending each dispersion liquid from each storage tank to the first storage tank 321. Separately, a storage tank containing a release agent particle dispersion liquid and a mixture in which the second resin particles and the release agent particle dispersion liquid are dispersed. Various methods may be adopted, such as a method of providing a storage tank for storing the dispersion liquid and feeding each dispersion liquid from each storage tank to the first storage tank 321 while changing the liquid sending speed.

As described above, the second agglomerated particles obtained by aggregating the second resin particles and the release agent particles on the surface of the first agglomerated particles are obtained.

-Fusion/unification process-
Next, with respect to the second aggregated particle dispersion liquid in which the second aggregated particles are dispersed, for example, the glass transition temperature of the first and second resin particles or higher (for example, 10 from the glass transition temperature of the first and second resin particles is used. To 30° C. or higher) to fuse and coalesce the second aggregated particles to form toner particles.

Toner particles are obtained through the above steps.
After obtaining the aggregated particle dispersion liquid in which the second aggregated particles are dispersed, the second aggregated particle dispersion liquid and the third resin particle dispersion liquid in which the third resin particles serving as the binder resin are dispersed are obtained. A step of further mixing and aggregating so that the third resin particles adhere to the surface of the second agglomerated particles to form third agglomerated particles; and a third agglomerated particle dispersion liquid in which the third agglomerated particles are dispersed. The toner particles may be manufactured through a step of heating the particles to fuse and coalesce the second aggregated particles to form toner particles having a core/shell structure.
By this operation, in the obtained toner particles (toner), the mode of the distribution of the uneven distribution B of the release agent domain becomes less than 1.00.

Here, after the fusion and coalescence step is completed, the toner particles formed in the solution are subjected to a known washing step, solid-liquid separation step, and drying step to obtain dried toner particles.
In the cleaning step, it is preferable to sufficiently perform displacement cleaning with ion-exchanged water from the viewpoint of charging property. The solid-liquid separation step is not particularly limited, but suction filtration, pressure filtration and the like are preferably performed from the viewpoint of productivity. The drying step is also not particularly limited in terms of method, but from the viewpoint of productivity, freeze drying, flash jet drying, fluidized drying, vibration type fluidized drying and the like may be performed.

Then, the toner according to the present exemplary embodiment is manufactured, for example, by adding an external additive to the obtained dry toner particles and mixing them. The mixing may be performed with, 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 separator or a wind separator.

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

The carrier is not particularly limited, and known carriers can be used. As the carrier, for example, a coated carrier obtained by coating a surface of a core material made of magnetic powder with a coating resin; a magnetic powder dispersion type carrier in which magnetic powder is dispersed and mixed in a matrix resin; porous magnetic powder is impregnated with resin. And the like.
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 which is coated with a coating resin.

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

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

Here, in order to coat the surface of the core material with the coating resin, a method of coating with the coating resin and a coating layer forming solution in which various additives as necessary are dissolved in a suitable solvent can be mentioned. The solvent is not particularly limited, and may be selected in consideration of the coating resin used, coating suitability and the like.
Specific resin coating methods include a dipping method in which the core material is immersed in a coating layer forming solution, a spray method in which the coating layer forming solution is sprayed on the surface of the core material, and a state in which the core material is suspended by flowing air. Examples thereof include a fluidized bed method of spraying a coating layer forming solution, a kneader coater method of removing a solvent by mixing a carrier core material and a coating layer forming solution in a kneader coater.

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, more preferably 3:100 to 20:100.

<Image forming apparatus/image forming method>
An image forming apparatus/image forming method according to this embodiment will be described.
The image forming apparatus according to this exemplary embodiment includes an image carrier, a charging unit that charges the surface of the image carrier, an electrostatic charge image forming unit that forms an electrostatic charge image on the charged surface of the image carrier, and an electrostatic charge. A developing unit that contains an image developer and develops the electrostatic image formed on the surface of the image carrier as a toner image by the electrostatic image developer, and a toner image formed on the surface of the image carrier as a recording medium. And a fixing means for fixing the toner image transferred on the surface of the recording medium. Then, the electrostatic charge image developer according to the exemplary embodiment is applied as the electrostatic charge image developer.

In the image forming apparatus according to the present exemplary embodiment, a charging step of charging the surface of the image carrier, an electrostatic charge image forming step of forming an electrostatic charge image on the surface of the charged image carrier, and an electrostatic charge according to the exemplary embodiment. A developing step of developing an electrostatic charge image formed on the surface of the image carrier as a toner image with the image developer; a transfer step of transferring the toner image formed on the surface of the image carrier to the surface of the recording medium; An image forming method (image forming method according to this 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 a direct transfer type apparatus that directly transfers the toner image formed on the surface of the image carrier to a recording medium; the toner image formed on the surface of the image carrier is used as an intermediate transfer body. A device of an intermediate transfer system that performs a primary transfer to the surface and secondarily transfers the toner image transferred to the surface of the intermediate transfer member to the surface of the recording medium; after the transfer of the toner image, the surface of the image carrier before charging is cleaned. A device including a cleaning unit; a known image forming device such as a device including a discharging unit that irradiates the surface of the image holding body with discharging light after charging the toner image and before charging, to remove the charge.
In the case of the apparatus of the intermediate transfer system, the transfer means 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 carrier to the surface of the intermediate transfer body. And a secondary transfer unit configured to secondarily transfer 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 exemplary embodiment, for example, the portion including the developing unit may have a cartridge structure (process cartridge) that is detachable from the image forming apparatus. As the process cartridge, for example, a process cartridge including a developing unit containing the electrostatic image developer according to the present exemplary embodiment is preferably used.

Hereinafter, an example of the image forming apparatus according to the present exemplary embodiment will be shown, but the 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. 1 is a schematic configuration diagram showing an image forming apparatus according to this embodiment.
The image forming apparatus shown in FIG. 1 is a first to an electrophotographic system that outputs images of respective colors of yellow (Y), magenta (M), cyan (C), and black (K) based on color-separated image data. The fourth image forming unit 10Y, 10M, 10C, 10K (image forming means) is provided. These image forming units (hereinafter, sometimes simply referred to as “units”) 10Y, 10M, 10C, and 10K are arranged side by side in the horizontal direction with a predetermined distance therebetween. The units 10Y, 10M, 10C, and 10K may be process cartridges that are detachable from the image forming apparatus.

Above the units 10Y, 10M, 10C, and 10K in the drawing, an intermediate transfer belt 20 as an intermediate transfer member extends through the units. The intermediate transfer belt 20 is provided by being wound around a driving roll 22 and a support roll 24 that are in contact with the inner surface of the intermediate transfer belt 20 and are spaced apart from each other in the left to right direction in the drawing. It is designed to run in the direction toward the unit 10K. A force is applied to the support roll 24 in a direction away from the drive roll 22 by a spring or the like (not shown), and tension is applied to the intermediate transfer belt 20 wound around the both. An intermediate transfer member cleaning device 30 is provided on the side of the image carrier of the intermediate transfer belt 20 so as to face the drive roll 22.
Further, the developing devices (developing means) 4Y, 4M, 4C, and 4K of the units 10Y, 10M, 10C, and 10K respectively include yellow, magenta, cyan, and black stored in toner cartridges 8Y, 8M, 8C, and 8K. The toner including the four color toners is supplied.

Since the first to fourth units 10Y, 10M, 10C, and 10K have the same configuration, here, the first unit for forming a yellow image is provided on the upstream side in the running direction of the intermediate transfer belt. 10Y will be described as a representative. It should be noted that the same units as the first unit 10Y are denoted by reference numerals with magenta (M), cyan (C), and black (K) instead of yellow (Y), so that the second to fourth portions are provided. The description of the units 10M, 10C, and 10K will be omitted.

The first unit 10Y has a photoconductor 1Y that functions as an image carrier. Around the photoconductor 1Y, a charging roll (an example of a charging unit) 2Y that charges the surface of the photoconductor 1Y to a predetermined potential, and the charged surface is exposed by a laser beam 3Y based on the color-separated image signal. To form an electrostatic charge image (an example of an electrostatic charge image forming unit) 3, a developing device (an example of a developing unit) 4Y that supplies toner charged to the electrostatic charge image to develop the electrostatic charge image, and develops A primary transfer roll 5Y (an example of a primary transfer unit) that transfers the toner image onto the intermediate transfer belt 20 and a photoconductor cleaning device (an example of a cleaning unit) 6Y that removes the toner remaining on the surface of the photoconductor 1Y after the primary transfer. Are arranged in order.
The primary transfer roll 5Y is arranged inside the intermediate transfer belt 20 and is provided at a position facing the photoconductor 1Y. Further, a bias power source (not shown) that applies a primary transfer bias is connected to each of the primary transfer rolls 5Y, 5M, 5C, and 5K. Each bias power source changes the transfer bias applied to each primary transfer roll under the control of a controller (not shown).

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

The electrostatic image is an image formed on the surface of the photoconductor 1Y by charging, and the laser beam 3Y lowers the specific resistance of the irradiated portion of the photosensitive layer, and the charged charge on the surface of the photoconductor 1Y flows. On the other hand, it is a so-called negative latent image formed by remaining electric charge in the portion not irradiated with the laser beam 3Y.
The electrostatic charge image formed on the photoconductor 1Y is rotated to a predetermined developing position as the photoconductor 1Y travels. Then, at this developing position, the electrostatic charge image on the photoconductor 1Y is made into a visible image (developed image) as a toner image by the developing device 4Y.

In the developing device 4Y, for example, an electrostatic image developer containing at least a yellow toner and a carrier is stored. The yellow toner is triboelectrically charged by being stirred inside the developing device 4Y, and has a charge of the same polarity (negative polarity) as the electrostatic charge charged on the photoconductor 1Y. One example) is held on. Then, as the surface of the photoconductor 1Y passes through the developing device 4Y, the yellow toner electrostatically adheres to the neutralized latent image portion on the surface of the photoconductor 1Y, and the latent image is developed by the yellow toner. .. The photoconductor 1Y on which the yellow toner image is formed continues to run at a predetermined speed, and the toner image developed on the photoconductor 1Y is conveyed to a predetermined primary transfer position.

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

Further, the primary transfer bias applied to the primary transfer rolls 5M, 5C, and 5K after the second unit 10M is also controlled according to the first unit.
In this way, the intermediate transfer belt 20 to which the yellow toner image is transferred by the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of the respective colors are superposed and transferred in multiple. It

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

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

The recording paper P, on which the fixing of the color image is completed, is carried out toward the discharge section, and the series of color image forming operations is completed.

<Process cartridge/Toner cartridge>
The process cartridge according to this embodiment will be described.
The process cartridge according to the present exemplary embodiment stores the electrostatic charge image developer according to the present exemplary embodiment, and develops the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer. And is a process cartridge that is attached to and detached from the image forming apparatus.

The process cartridge according to the present embodiment is not limited to the above-described configuration, and the developing device and other means such as an image carrier, a charging unit, an electrostatic charge image forming unit, and a transfer unit, if necessary. And at least one selected from the above.

Hereinafter, an example of the process cartridge according to the present embodiment will be shown, but the process cartridge 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 showing the process cartridge according to the present embodiment.
The process cartridge 200 shown in FIG. 2 includes, for example, a photoconductor 107 (an example of an image carrier) 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 roll 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 to form a cartridge. There is.
In FIG. 2, 109 is an exposure device (an example of electrostatic charge image forming means), 112 is a transfer device (an example of transfer means), 115 is a fixing device (an example of fixing means), and 300 is recording paper (of a recording medium). One example) is shown.

Next, the toner cartridge according to the present exemplary embodiment will be described.
The toner cartridge according to this exemplary embodiment is a toner cartridge that contains the toner according to this exemplary embodiment and is attached to and detached from the image forming apparatus. The toner cartridge contains replenishment toner to be supplied to the developing means provided in the image forming apparatus.

The image forming apparatus shown in FIG. 1 is an image forming apparatus having a configuration in which the toner cartridges 8Y, 8M, 8C, and 8K are attached and detached, and the developing devices 4Y, 4M, 4C, and 4K are the respective developing devices (colors). ) And a toner cartridge corresponding to () are connected by a toner supply pipe (not shown). Further, when the toner contained in the toner cartridge is used up, this toner cartridge is replaced.

Hereinafter, the present embodiment will be described in more detail with reference to examples and comparative examples, but the present embodiment is not limited to these examples. In addition, "part" means "part by mass" unless otherwise specified.

<Preparation of resin particle dispersion>
[Preparation of Resin Particle Dispersion (1)]
-Terephthalic acid: 30 mol parts-Fumaric acid: 70 mol parts-Bisphenol A ethylene oxide adduct: 5 mol parts-Bisphenol A propylene oxide adduct: 95 mol parts Stirrer, nitrogen inlet pipe, temperature sensor, and rectification column The above material was charged into a flask having an internal capacity of 5 liter equipped with, and the temperature was raised to 210° C. over 1 hour, and 1 part of titanium tetraethoxide was added to 100 parts of the material. The temperature was raised to 230° C. over 0.5 hour while distilling off the produced water, the dehydration condensation reaction was continued at this temperature for 1 hour, and then the reaction product was cooled. Thus, a polyester resin (1) having a weight average molecular weight of 18,500, an acid value of 14 mgKOH/g and a glass transition temperature of 59° C. was synthesized.

40 parts of ethyl acetate and 25 parts of 2-butanol were put into a container equipped with a temperature adjusting means and a nitrogen replacing means, and after being used as a mixed solvent, 100 parts of the polyester resin (1) was gradually added and dissolved therein. A 10% by mass aqueous ammonia solution (corresponding to a 3-fold amount equivalent to the acid value of the resin) was added and stirred for 30 minutes.
Then, the inside of the container was replaced with dry nitrogen, the temperature was maintained at 40° C., and 400 parts of ion-exchanged water was added dropwise at a rate of 2 parts/min while stirring the mixed solution to perform emulsification. After completion of the dropping, the emulsion was returned to room temperature (20°C to 25°C), and bubbling was performed for 48 hours with dry nitrogen while stirring to reduce ethyl acetate and 2-butanol to 1,000 ppm or less to obtain a volume average particle size. A resin particle dispersion liquid in which resin particles having a diameter of 200 nm were dispersed was obtained. Ion-exchanged water was added to the resin particle dispersion liquid to adjust the solid content to 20% by mass to obtain a resin particle dispersion liquid (1).

<Preparation of colorant particle dispersion>
[Preparation of colorant particle dispersion (1)]
Cyan pigment C.I. I. Pigment Blue 15:3 (Copper phthalocyanine DIC, trade name: FASTOGEN BLUE LA5380): 70 parts/anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 5 parts/ion exchanged water: 200 Parts The above materials were mixed and dispersed for 10 minutes using a homogenizer (Ultra Turrax T50 manufactured by IKA). Ion-exchanged water was added so that the solid content in the dispersion was 20% by mass to obtain a colorant particle dispersion liquid (1) in which colorant particles having a volume average particle diameter of 190 nm were dispersed.

<Preparation of release agent particle dispersion>
[Preparation of Release Agent Particle Dispersion (1)]
Paraffin wax (HNP-9 manufactured by Nippon Seiro Co., Ltd.) 100 parts Anionic surfactant (Neogen RK manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) 1 part Ion-exchanged water 350 parts Mix the above materials After heating to 100° C. and using a homogenizer (Ultra Turrax T50 manufactured by IKA) to disperse, a dispersion treatment with a Manton-Gaulin high pressure homogenizer (manufactured by Gorin) was performed to disperse release agent particles having a volume average particle diameter of 200 nm. Thus, a release agent particle dispersion liquid (1) (solid content 20% by mass) was obtained.

<Example 1>
[Preparation of toner particles]
A round stainless steel flask and a container A were connected by a tube pump A, the containing liquid contained in the container A was sent to the flask by driving the tube pump A, and the container A and the container B were connected by a tube pump B. An apparatus (see FIG. 3) for feeding the contained liquid contained in the container B to the container A by driving the tube pump B was prepared. And the following operation was implemented using this apparatus.

-Resin particle dispersion liquid (1): 500 parts-Colorant particle dispersion liquid (1): 40 parts-Anionic surfactant (TaycaPower): 2 parts After adding nitric acid to adjust the pH to 3.5, 30 parts of an aqueous nitric acid solution having a polyaluminum chloride concentration of 10% by mass was added. Subsequently, the particles were dispersed at 30° C. using a homogenizer (Ultra Turrax T50 manufactured by IKA Co., Ltd.), and then the particle size of the agglomerated particles was grown while raising the temperature at a pace of 1° C./30 minutes in a heating oil bath. It was
On the other hand, 150 parts of the resin particle dispersion liquid (1) was placed in a container A of a polyester bottle, and 25 parts of the release agent particle dispersion liquid (1) was also placed in the container B. Next, the liquid feed rate of the tube pump A was set to 0.70 parts/minute, and the liquid feed rate of the tube pump B was set to 0.14 parts/minute, and the inside of the round stainless steel flask during the formation of aggregated particles was set. From the time when the temperature reached 37.0° C., the tube pumps A and B were driven to start the feeding of each dispersion liquid. As a result, the mixed dispersion liquid in which the resin particles and the release agent particles were dispersed was fed from the container A to the round-shaped stainless steel flask in which the agglomerated particles are being formed, while gradually increasing the concentration of the release agent particles.
Then, after the liquid transfer of each dispersion liquid to the flask was completed and the temperature inside the flask reached 48° C., the temperature was kept for 30 minutes to form the second aggregated particles.

Then, 50 parts of the resin particle dispersion liquid (1) was slowly added and maintained for 1 hour, and a pH of the solution was adjusted to 8.5 by adding a 0.1 N sodium hydroxide aqueous solution. Heated to 0°C and held for 5 hours. Then, the mixture was cooled to 20° C. at a rate of 20° C./minute, filtered, sufficiently washed with ion-exchanged water, and dried to obtain toner particles (1) having a volume average particle diameter of 6.0 μm.

[Preparation of toner]
Toner (1) was mixed with 100 parts of toner particles (1) and 0.7 parts of dimethyl silicone oil-treated silica particles (RY200 manufactured by Nippon Aerosil Co., Ltd.) using a Henschel mixer (peripheral speed 30 m/sec, 3 minutes). Got

[Preparation of developer]
・Ferrite particles (average particle size 50 μm) 100 parts ・Toluene 14 parts ・Styrene/methyl methacrylate copolymer (copolymerization ratio 15/85) 3 parts ・Carbon black 0.2 parts The above components except ferrite particles are sand milled. A dispersion was prepared by dispersing, and this dispersion was put together with ferrite particles in a vacuum degassing type kneader, and the pressure was reduced with stirring to dry the carrier to obtain a carrier.
Then, 8 parts of the toner (1) was mixed with 100 parts of the carrier to obtain a developer (1).

<Example 2>
In the production of the toner particles (1), the liquid feeding speed of the tube pump A was set to 0.55 parts/minute, and the liquid feeding speed of the tube pump B was set to 0.11 parts/minute, and the temperature inside the flask was 33. Toner particles (2) were obtained in the same manner as in Example 1 except that the tube pumps A and B were driven from the time when the temperature reached 0.0°C. The obtained toner particles (2) had a volume average particle diameter of 5.9 μm. Then, using the toner particles (2), a toner (2) and a developer (2) were obtained in the same manner as in Example 1.

<Example 3>
In the production of the toner particles (1), the liquid feed rate of the tube pump A was set to 0.80 part/min, the liquid feed rate of the tube pump B was set to 0.16 part/min, and the temperature in the flask was set to 35. Toner particles (3) were obtained in the same manner as in Example 1 except that the tube pumps A and B were driven from the time when the temperature reached 0.0°C. The obtained toner particles (3) had a volume average particle diameter of 5.3 μm. Then, using the toner particles (3), a toner (3) and a developer (3) were obtained in the same manner as in Example 1.

<Example 4>
In the production of the toner particles (1), the liquid feed rate of the tube pump A was set to 0.58 part/min, the liquid feed rate of the tube pump B was set to 0.11 part/min, and the temperature in the flask was set to 39. Toner particles (4) were obtained in the same manner as in Example 1 except that the tube pumps A and B were driven from the time when the temperature reached 0.0°C. The obtained toner particles (4) had a volume average particle diameter of 5.6 μm. Then, using the toner particles (4), a toner (4) and a developer (4) were obtained in the same manner as in Example 1.

<Example 5>
In the production of the toner particles (1), the liquid feed rate of the tube pump A was set to 0.84 part/min, the liquid feed rate of the tube pump B was set to 0.17 part/min, and the temperature in the flask was set to 41. Toner particles (5) were obtained in the same manner as in Example 1 except that the tube pumps A and B were driven from the time when the temperature reached 0.0°C. The obtained toner particles (5) had a volume average particle diameter of 5.7 μm. Then, using the toner particles (5), a toner (5) and a developer (5) were obtained in the same manner as in Example 1.

<Comparative Example 1>
In the production of the toner particles (1), the liquid feed rate of the tube pump A was set to 0.55 parts/min, the liquid feed rate of the tube pump B was set to 0.11 parts/min, and the temperature in the flask was set to 30. Toner particles (C1) were obtained in the same manner as in Example 1 except that the tube pumps A and B were driven from the time when the temperature reached 0.0°C. The obtained toner particles (C1) had a volume average particle diameter of 5.2 μm. Then, using the toner particles (C1), a toner (C1) and a developer (C1) were obtained in the same manner as in Example 1.

<Comparative example 2>
In the production of the toner particles (1), the liquid feed rate of the tube pump A was set to 0.84 part/min, the liquid feed rate of the tube pump B was set to 0.17 part/min, and the temperature in the flask was set to 33. Toner particles (C2) were obtained in the same manner as in Example 1 except that the tube pumps A and B were driven from the time when the temperature reached 0.0°C. The obtained toner particles (C2) had a volume average particle diameter of 6.0 μm. Then, using the toner particles (C2), a toner (C2) and a developer (C2) were obtained in the same manner as in Example 1.

<Comparative example 3>
In the production of the toner particles (1), the liquid feed rate of the tube pump A was set to 0.51 part/min, the liquid feed rate of the tube pump B was set to 0.10 part/min, and the temperature in the flask was set to 31. Toner particles (C3) were obtained in the same manner as in Example 1 except that the tube pumps A and B were driven from the time when the temperature reached 0.0°C. The obtained toner particles (C3) had a volume average particle diameter of 5.9 μm. Then, using the toner particles (C3), a toner (C3) and a developer (C3) were obtained in the same manner as in Example 1.

<Comparative example 4>
In the production of the toner particles (1), the liquid feed rate of the tube pump A was set to 0.90 part/minute, and the liquid feed rate of the tube pump B was set to 0.19 part/1 minute, and the temperature in the flask was set to 35. Toner particles (C4) were obtained in the same manner as in Example 1 except that the tube pumps A and B were driven from the time when the temperature reached 0.0°C. The obtained toner particles (C4) had a volume average particle diameter of 6.1 μm. Then, using the toner particles (C4), a toner (C4) and a developer (C4) were obtained in the same manner as in Example 1.

<Comparative Example 5>
In the production of the toner particles (1), the liquid feeding speed of the tube pump A was set to 0.50 parts/minute, the liquid feeding speed of the tube pump B was set to 0.10 parts/minute, and the temperature in the flask was set to 38. Toner particles (C5) were obtained in the same manner as in Example 1 except that the tube pumps A and B were driven from the time when the temperature reached 0.0°C. The obtained toner particles (C5) had a volume average particle diameter of 5.4 μm. Then, using the toner particles (C5), a toner (C5) and a developer (C5) were obtained in the same manner as in Example 1.

<Comparative example 6>
In the production of the toner particles (1), the liquid feeding speed of the tube pump A was set to 0.89 parts/min, the liquid feeding speed of the tube pump B was set to 0.19 parts/min, and the temperature in the flask was set to 42. Toner particles (C6) were obtained in the same manner as in Example 1 except that the tube pumps A and B were driven from the time when the temperature reached 0.0°C. The obtained toner particles (C6) had a volume average particle diameter of 5.5 μm. Then, using the toner particles (C6), a toner (C6) and a developer (C6) were obtained in the same manner as in Example 1.

<Example 6>
In the production of the toner particles (1), the liquid feeding speed of the tube pump A was set to 0.75 parts/minute, and the liquid feeding speed of the tube pump B was set to 0.11 parts/minute, and the temperature inside the flask was set to 37. Tube pumps A and B were driven from the time when the temperature reached 0.0° C., and the liquid transfer rate of the tube pump B was changed to 0.19 part/minute at the time when the temperature inside the flask reached 40° C. In the same manner as in Example 1, toner particles (6) were obtained. The obtained toner particles (6) had a volume average particle diameter of 5.9 μm. Then, using the toner particles (6), a toner (6) and a developer (6) were obtained in the same manner as in Example 1.

<Example 7>
In the production of the toner particles (1), the liquid feeding speed of the tube pump A was set to 0.75 parts/minute, and the liquid feeding speed of the tube pump B was set to 0.14 parts/minute, and the temperature inside the flask was set to 35. Tube pumps A and B were driven from the time when the temperature reached 0.0° C., and the liquid transfer rate of the tube pump B was changed to 0.10 part/1 minute when the temperature inside the flask reached 39° C. In the same manner as in Example 1, toner particles (7) were obtained. The obtained toner particles (7) had a volume average particle diameter of 5.9 μm. Then, using the toner particles (7), a toner (7) and a developer (7) were obtained in the same manner as in Example 1.

<Reference example 1>
In the production of the toner particles (1), the liquid feed rate of the tube pump A was set to 0.75 parts/minute, the liquid feed rate of the tube pump B was set to 0.11 parts/minute, and the temperature inside the flask was set to 35. Tube pumps A and B were driven from the time when the temperature reached 40° C., and when the temperature inside the flask reached 40° C., except that the liquid feed rate of the tube pump B was changed to 0.22 parts/1 minute, Toner particles (R1) were obtained in the same manner as in Example 1. The obtained toner particles (R1) had a volume average particle diameter of 5.8 μm. Then, using the toner particles (R1), a toner (R1) and a developer (R1) were obtained in the same manner as in Example 1.

<Reference example 2>
In the production of the toner particles (1), the liquid feeding speed of the tube pump A was set to 0.75 parts/minute, the liquid feeding speed of the tube pump B was set to 0.14 parts/minute, and the temperature in the flask was set to 35. Tube pumps A and B were driven from the time when the temperature reached ℃, and when the temperature in the flask reached 39° C., except that the liquid feed rate of the tube pump B was changed to 0.08 parts/1 minute, Toner particles (R2) were obtained in the same manner as in Example 1. The obtained toner particles (R2) had a volume average particle diameter of 5.6 μm. Then, using the toner particles (R2), a toner (R2) and a developer (R2) were obtained in the same manner as in Example 1.

<Various measurements>
With respect to the toner of the developer obtained in each example, the mode, skewness, and kurtosis of the distribution of the uneven distribution B of the release agent domain were measured according to the method described above. The results are shown in Table 1.

<Evaluation>
The following evaluation was performed using the developer obtained in each example. The results are shown in Table 1.

[Evaluation of peelability and uneven gloss]
The following work and image formation were performed in an environment of temperature 25° C./humidity 60%.
As an image forming apparatus for forming an image for evaluation, an apparatus prepared by modifying Fuji Xerox's 700 Digital Color Press to output an unfixed image up to the edge of the paper is prepared. (The same toner as the toner contained in the developer) was put in the toner cartridge. Continuously, an embossed paper (Resac 66 White manufactured by Fuji Xerox Co., Ltd., basis weight 151 g/m ² ) is formed with a 200% density of the secondary color to form a solid image without a leading edge margin, and the fixing temperature is set to 180° C. The process speed was set to 220 mm/sec and 100 sheets were continuously output. The following evaluations were performed on the obtained first and 100th images.

-Evaluation of releasability-
The state of the leading edge of the paper was observed for the obtained first and 100th images, and evaluated according to the following criteria.
A: No peeling failure occurred, and the state of the leading edge of the paper was good.
B: Peeling failure has not occurred and the leading edge of the paper is slightly curled.
C: Roughness of the leading edge of the image occurs due to peeling failure.
D: Paper cannot be peeled off and paper wrapping occurs.

-Evaluation of uneven gloss-
The first and 100th images obtained were subjected to 60-degree gloss measurement using a portable gloss meter (BYK Gardner Micro Trigloss, manufactured by Toyo Seiki Seisaku-sho, Ltd.). The standard deviation σ is calculated for the total 50 data of the gross values obtained by randomly measuring 10 times at each of 5 positions of the front left end/front right end/rear end left end/rear end right end/center part. It was used as an index of uneven gloss.
A: σ<3.0
B: 3.0≦σ<5.0
C: 5.0≦σ<8.0
D: 8.0≦σ

From the above results, it can be seen that in this example, as compared with the comparative example, good results were obtained regarding the evaluation of peeling failure and uneven gloss.
In particular, Examples 6 to 7 in which the kurtosis of the distribution of the uneven distribution B of the release agent domain is in the range of −0.20 or more and +1.50 or less, are defective in peeling and uneven in gloss as compared with Reference Examples 1 and 2. It can be seen that good results were obtained for both evaluations.

1Y, 1M, 1C, 1K photoconductors (an example of an image carrier)
2Y, 2M, 2C, 2K charging roll (an example of charging means)
3 Exposure device (an example of electrostatic charge image forming means)
3Y, 3M, 3C, 3K Laser beam 4Y, 4M, 4C, 4K Developing device (an example of developing means)
5Y, 5M, 5C, 5K Primary transfer roll (an example of primary transfer means)
6Y, 6M, 6C, 6K Photoconductor cleaning device (an example of cleaning means)
8Y, 8M, 8C, 8K Toner cartridges 10Y, 10M, 10C, 10K Image forming unit 20 Intermediate transfer belt (an example of an intermediate transfer member)
22 drive roll 24 support roll 26 secondary transfer roll (an example of secondary transfer means)
30 Intermediate Transfer Body Cleaning Device 107 Photoconductor (an example of image carrier)
108 charging roll (an example of charging means)
109 exposure apparatus (an example of electrostatic charge image forming means)
111 developing device (an example of developing means)
112 transfer device (an example of transfer means)
113 photoconductor cleaning device (an example of cleaning means)
115 fixing device (an example of fixing means)
116 Mounting Rail 118 Opening 117 for Exposure 117 Housing 200 Process Cartridge 300 Recording Paper (Example of Recording Medium)
P recording paper (an example of recording medium)

Claims (7)

Including a binder resin, a colorant, and a release agent,
A sea-island structure having a sea part containing the binder resin and an island part containing the release agent,
The mode of distribution of the uneven distribution B of the island portion including the release agent represented by the following formula (1) is 0.75 or more and 1.00 or less, and the skewness of the distribution of the uneven distribution B is -1. 10 or more and −0.50 or less,
Toner
The first resin particle dispersion liquid in which the first resin particles serving as the binder resin are dispersed, and the colorant particle dispersion liquid in which the particles of the colorant are dispersed are mixed, and each particle in the obtained dispersion liquid is mixed. And a step of forming first aggregated particles,
After obtaining the first aggregated particle dispersion liquid in which the first aggregated particles are dispersed, the mixed dispersion liquid in which the second resin particles serving as the binder resin and the particles of the release agent are dispersed is used as the mixed dispersion liquid. While gradually increasing the concentration of the particles of the release agent therein, the particles are sequentially added to the first aggregated particle dispersion liquid to further aggregate the second resin particles and the particles of the release agent on the surface of the first aggregated particles. Then, in the step of forming the second agglomerated particles, or in the agglomeration process of forming the first agglomerated particles, while gradually increasing the addition rate or increasing the concentration of the particles of the release agent, A step of adding a release agent particle dispersion liquid in which particles are dispersed, promoting the aggregation of each particle, and forming second aggregated particles;
Heating the second aggregated particle dispersion liquid in which the second aggregated particles are dispersed to fuse and coalesce the second aggregated particles to form toner particles;
A toner for developing an electrostatic charge image, which is a toner obtained through a process including
Formula (1): Uneven distribution B=2d/D
(In the formula (1), D represents the equivalent circle diameter (μm) of the toner in observing the cross section of the toner. d represents the distance from the center of gravity of the toner in observing the cross section of the toner to the center of gravity of the island portion including the release agent ( μm) is shown.) The electrostatic charge image developing toner according to claim 1, wherein the distribution k of the uneven distribution B is −0.20 or more and +1.50 or less. An electrostatic image developer containing the toner for developing an electrostatic image according to claim 1 or 2. A toner containing the electrostatic image developing toner according to claim 1 or 2,
A toner cartridge that is attached to and detached from the image forming apparatus. A developing means for accommodating the electrostatic charge image developer according to claim 3, and developing the electrostatic charge image formed on the surface of the image carrier with the electrostatic charge image developer as a toner image,
A process cartridge that is attached to and detached from an image forming apparatus. An image carrier,
Charging means for charging the surface of the image carrier,
Electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image carrier,
A developing unit that contains the electrostatic image developer according to claim 3, and develops the electrostatic image formed on the surface of the image carrier 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 a recording medium,
Fixing means for fixing the toner image transferred to the surface of the recording medium,
An image forming apparatus including. A charging step of charging the surface of the image carrier,
An electrostatic charge image forming step of forming an electrostatic charge image on the surface of the charged image carrier;
A developing step of developing the electrostatic charge image formed on the surface of the image carrier as a toner image with the electrostatic charge image developer according to claim 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 onto the surface of the recording medium,
An image forming method having: