JP6543903B2 - Electrostatic image developing toner, 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 electrostatic charge image formation. Then, a toner image is formed on the surface of the image carrier with a developer containing toner, and after this toner image is transferred to a recording medium, the toner image is fixed to the recording medium. Through these steps, image information is visualized as an image.

  For example, in Patent Document 1, “the wax is contained in the form of fine particles in the toner, the wax is present in the entire area from the vicinity of the surface to the inside of the toner, and the concentration of the wax present in the vicinity of the surface of the toner is the inside of the toner "Dry toner" which is greater than the concentration of wax present in Further, Patent Document 1 discloses that “in the kneading and pulverizing method, a localized distribution control resin having both a portion close to the polarity of the binder resin and a portion close to the polarity of the release agent is used”.

  According to Patent Document 2, “the content of 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 binding resin, and the degree of uneven distribution of wax in the depth direction of the toner Is being controlled "is disclosed. Further, Patent Document 2 discloses that “the position of the wax is disposed in the vicinity of the surface by controlling the difference in hydrophilicity / hydrophobicity between the binder resin and the wax dissolved in the solvent”.

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

  An object of the present invention is to suppress the peeling defect of the recording medium at the time of fixing, and to form the image unevenness on the recording medium having a large surface unevenness (hereinafter referred to simply as the “image unevenness of the image”). To provide a toner for developing an electrostatic charge image.

  The above-mentioned subject is solved by the following means.

< 1 >
Containing binder resin, coloring agent, and mold release agent,
It has a sea-island structure having a sea part containing the binder resin and an island part containing the release agent,
The mode of the distribution of the uneven distribution degree B of the island portion containing the mold release agent shown 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 degree B is -1. Toner for developing an electrostatic charge image, which is 10 or more and -0.50 or less.
Equation (1): Degree of uneven distribution B = 2 d / D
(In Formula (1), D represents the equivalent circle diameter (μm) of the toner in the cross-sectional observation of the toner, d represents the distance from the center of gravity of the toner in the cross-sectional observation of the toner to the center of the island including the releasing agent μm)))

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

< 3 > ,
The electrostatic charge image developer containing the toner for electrostatic charge image development as described in < 1 > or < 2 > .

< 4 > ,
The toner for electrostatic image development as described in < 1 > or < 2 > is accommodated,
A toner cartridge that is attached to and removed from the image forming apparatus.

< 5 > ,
A developer unit containing the electrostatic charge image developer described in < 3 >, and developing the electrostatic charge image formed on the surface of the image carrier as the toner image by the electrostatic charge image developer;
Process cartridge that is attached to and detached from the 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;
Developing means for containing the electrostatic charge image developer described in < 3 > and developing the electrostatic charge image formed on the surface of the image carrier as the toner image by the electrostatic charge image developer;
A transfer unit configured to transfer a toner image formed on the surface of the image carrier to the surface of a recording medium;
Fixing means for fixing the toner image transferred to the surface of the recording medium;
An image forming apparatus comprising:

< 7 > ,
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;
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 > ;
Transferring the toner image formed on the surface of the image carrier to the surface of the recording medium;
A fixing step of fixing the toner image transferred to the surface of the recording medium;
An image forming method comprising:

According to the invention related to < 1 > , the mode of the distribution of the degree of uneven distribution B is less than 0.75, or the skewness of the distribution of the degree of 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 at the time of fixing and suppresses unevenness of gloss of an image.
According to the invention related to < 2 > , compared to the case where the kurtosis of the distribution of the uneven distribution degree B is less than −0.20 or more than +1.50, the peeling defect of the recording medium at the time of fixing is suppressed and the gloss of the image Provided is a toner for developing an electrostatic charge image which suppresses unevenness.

According to the invention relating to < 3 > , < 4 > , < 5 > , < 6 > , or < 7 > , the mode of the distribution of the uneven distribution B is less than 0.75, or the strain of the distribution of the uneven distribution B Electrostatic charge image that suppresses peeling failure of the recording medium at the time of fixing and suppresses uneven gloss of the image as compared with the case where the electrostatic charge image developing toner having a degree of less than −0.20 or more 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 view showing an example of an image forming apparatus according to the present embodiment. It is a schematic block diagram which shows an example of the process cartridge which concerns on this embodiment. It is a schematic diagram for demonstrating a power feed addition method. FIG. 6 is a view showing an example of the distribution of the uneven distribution degree B of the release agent domain 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 electrostatic image development)
The electrostatic charge image developing toner (hereinafter, referred to as “toner”) according to the exemplary embodiment includes a binder resin, a colorant, and a release agent. In addition, the toner according to the present embodiment has a sea-island structure having a sea part containing a binder resin and an island part containing a release agent.
And in this sea-island structure, the mode of the distribution of the uneven distribution degree B of the island portion containing the releasing agent shown by the formula (1) is 0.75 or more and 1.00 or less, and the distortion of the distribution of the uneven distribution degree B The degree is −1.10 or more and −0.50 or less.
Equation (1): Degree of uneven distribution B = 2 d / D
(In Formula (1), D represents the equivalent circle diameter (μm) of the toner in the cross-sectional observation of the toner, d represents the distance from the center of gravity of the toner in the cross-sectional observation of the toner to the center of μm)))

  With the above configuration, the toner according to the present embodiment suppresses peeling failure of the recording medium at the time of fixation, and unevenness in image gloss (image glossiness) occurs when an image is formed on the recording medium having large surface irregularities. Control the unevenness). The reason is not clear, but is presumed to be due to the following reasons.

In recent years, with regard to image formation by electrophotography (hereinafter also referred to as “printing”), the demand for the light printing market such as on-demand printing (a method of printing according to a request) is increasing. And in this light printing market, printing which can not be seen in the office or in-company printing market (so-called office printing market) is required. Specifically, printing on various types of recording media such as embossed paper, printing without blanks at the leading end of the recording media (so-called borderless printing), and the like are required.
For this reason, in the light printing market, more characteristics than before are required. One of the characteristics is, for example, releasability. In particular, in borderless printing, an image is apt to be roughened due to a peeling defect at the time of fixing of the toner, and the toner is required to have releasability higher than before.

  In order to improve the releasability, it is known that the release agent is unevenly distributed in the surface layer portion of the toner. The toner in which the releasing agent is unevenly distributed in the surface layer portion has a property that the releasing agent is likely to exude when fixing. Therefore, the toner having this property is improved in releasability.

  However, when an image is formed on a recording medium having large surface irregularities, such as embossed paper, with the toner in which the release agent is unevenly distributed in the surface layer portion, the gloss unevenness of the image may occur. In a recording medium having large surface irregularities, the toner image before fixing is fixed in a state where toner is present on each of the convexes and concaves on the surface of the recording medium. At this time, the toner present in the recess is less susceptible to the fixing pressure than the toner present in the protrusion. In other words, the toner present in the concave portion is less likely to contact the fixing unit (for example, a fixing member such as a fixing roll or a fixing belt) than the toner present in the convex portion.

  On the other hand, the toner in which the release agent is unevenly distributed in the surface layer portion exudes the release agent even if it is present in the concave portion where pressure is not easily received. The release agent exuded from the toner present in the convex portion is transferred to the fixing means by contact with the fixing means, but the toner from the toner present in the recess is difficult to contact with the fixing means, so the fixing means It is difficult to shift to the bottom, and easily remains in the recess. For this reason, in the image after fixing, the amount of the release agent remaining in the convex portion and the concave portion on the surface of the recording medium is different, and this appears as gloss unevenness.

  Here, the degree of uneven distribution B of the island portion containing 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. . As the uneven distribution B is larger, the release agent domain is present closer to the toner surface, and as the value is smaller, the release agent domain is present closer to the toner center. Then, the mode of the distribution of the uneven distribution degree B indicates a portion where the release agent domain is most present in the radial direction of the toner. On the other hand, the skewness of the distribution of the uneven distribution degree B indicates the left-right symmetry of the distribution. Specifically, the skewness of the distribution of the uneven distribution degree B indicates the degree of tailing of the distribution from the mode value. That is, the skewness of the distribution of the uneven distribution degree B indicates how much the release agent domain is present from the most site in the radial direction of the toner.

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

  As described above, in the toner in which the mode and skewness of the distribution of uneven distribution degree B of the release agent domain satisfy the above range, the release agent domain is most abundant in the surface layer portion, and the surface layer portion from the toner with a gradient Toner distributed toward the The toner having a gradient in the distribution of the release agent domain has a property that only the release agent on the surface layer of the toner exudes when subjected to low pressure, and the release agent in the toner exudes also when subjected to high pressure. That is, in the toner having a concentration gradient of the release agent domain, the amount of release of the release agent is controlled according to the pressure.

When an image is formed on a recording medium having large irregularities on the surface such as embossed paper with toner having this property, the toner present on the convex part of the recording medium receives a sufficient pressure at the time of fixing, so the toner inside is separated. The mold agent also exudes and exhibits sufficient releasability. On the other hand, since the toner present in the concave portion of the recording medium is unlikely to be subjected to pressure during fixing, only the release agent on the surface layer side of the toner leaks out. That is, the exudation of excess release agent is suppressed in the recess.
For this reason, 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 is reduced.

  From the above, the toner according to the exemplary embodiment suppresses the peeling failure of the recording medium at the time of fixing, and the unevenness in the gloss of the image (the unevenness in the gloss of the image occurs when the image is formed on the recording medium having large surface unevenness ) Is supposed to suppress.

  Incidentally, conventionally, a toner (Japanese Patent Laid-Open No. 2004-145243, etc.) and a binder resin in which the position of the release agent is disposed near the surface by utilizing the difference in hydrophilicity / hydrophobicity between the binder resin and the release agent A toner (Japanese Patent Laid-Open No. 2011-158758, etc.) in which the position of the release agent is located near the surface is known by a kneading and pulverizing method using an uneven distribution control resin having both a portion close to polarity and a portion close to polarity of the release agent. ing. However, in any toner, 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 can not have a gradient.

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

  The toner according to the present 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 is present in the form of islands in the continuous phase of the binder resin. The release agent domain is preferably not present at the central portion (center of gravity) of the toner in cross-sectional observation of the toner, from the viewpoint of suppression of peeling failure and suppression of uneven gloss.

  In the toner having a sea-island structure, the mode of the distribution of the uneven distribution degree B of the release agent domain (island portion including the release agent) is 0.75 or more and 1.00 or less, and suppression of peeling failure and gloss unevenness suppression From the viewpoint of the above, 0.80 or more and 0.95 or less is preferable, and 0.85 or more and 0.90 or less is more preferable. In particular, the mode of the distribution of the uneven distribution degree B of the releasing agent domain is preferably 0.98 or less from the viewpoint of the heat storage property of the toner.

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

The kurtosis of the distribution of the uneven distribution degree B of the release agent domain (island portion including the release agent) is preferably -0.20 or more and +1.50 or less from the viewpoint of suppression of peeling failure and suppression of gloss unevenness, -0. 15 or more and +1.40 or less are more preferable, and -0.10 or more and +1.30 or less are more preferable.
The kurtosis is an index indicating the peak of the top of the distribution of the uneven distribution B (that is, the mode of the distribution). And, in the distribution of the uneven distribution degree B, the kurtosis in the above-mentioned range indicates a state in which the apex (mode value) is not excessively sharp but is a distribution which is appropriately curved while being sharpened. For this reason, the change in the stain amount of the release agent from the toner according to the pressure becomes smooth, and the amount of the release agent from the toner in the convex portions and the concave portions of the recording medium is easily maintained properly. 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 by, for example, a method of observing a cross section of the toner (toner particles) with a transmission electron microscope, or staining of the toner particles with ruthenium tetraoxide on a cross section and observing with a scanning electron microscope. The method of observing with a scanning electron microscope is preferable in that the releasing agent domain in the cross section of the toner can be observed more clearly. The scanning electron microscope may be of a type well known to those skilled in the art, and examples thereof include SU8020 manufactured by Hitachi High-Tech, JSM-7500F manufactured by JEOL.
The specific observation method is as follows. First, a toner (toner particles) to be measured is embedded in an epoxy resin, and then the epoxy resin is cured. The cured product is sliced by a microtome equipped with a diamond blade to obtain an observation sample in which the cross section of the toner is exposed. The thin observation sample is stained with ruthenium tetraoxide, and the cross section of the toner is observed by a scanning electron microscope. According to this observation method, a sea-island structure in which a releasing agent having a luminance difference (contrast) exists in the form of islands with respect to the continuous phase of the binder resin is observed in the cross section of the toner.

Next, a method of measuring the uneven distribution degree B of the release agent domain will be described.
The measurement of the uneven distribution degree B of the release agent domain is performed as follows. First, an image is recorded at a magnification at which a cross section of one toner (toner particle) enters a field of view using a method of confirming the sea-island structure. The image analysis is performed on the recorded image under 0.010000 μm / pixel conditions using an image analysis software (WinROOF manufactured by Mitani Corporation). By this image analysis, the shape of the cross section of the toner is extracted based on the brightness difference (contrast) between the epoxy resin used for embedding and the binder resin of the toner. The projected area is obtained based on the shape of the cross section of the extracted toner. Then, the equivalent circle diameter is obtained from this projected area. The equivalent circle diameter is calculated by the equation: 2√ (projected area / π). The equivalent circle diameter obtained is taken as the equivalent circle diameter D of the toner in the cross-sectional observation of the toner.
On the other hand, the position of the center of gravity is determined based on the shape of the cross section of the extracted toner. Subsequently, the shape of the release agent domain is extracted based on the brightness difference (contrast) of the binder resin and the release agent, and the center of gravity position of the release agent domain is determined. Specifically, each barycentric position corresponds to the number of pixels in the region of the extracted toner or release agent domain, and the xy coordinates of each pixel as x _i , y _i (i = 1 , 2,..., N), the x coordinate of the center of gravity is obtained by dividing the sum of each x _i coordinate value by n, and the y coordinate of the center of gravity is obtained by dividing the sum of each y _i coordinate value by n. Then, the distance between the center of gravity of the cross section of the toner and the center of gravity of the releasing agent domain is determined. The determined distance is taken as the distance d from the center of gravity of the toner in the cross-sectional observation of the toner to the center of gravity of the island portion containing the releasing agent.
Finally, the degree of uneven distribution B of the release agent domain is determined from the equivalent circle diameter D and the distance d, according to the equation (1): degree of uneven distribution B = 2 d / D. Then, the uneven distribution B of the release agent domain is determined by performing the same operation as described above for each of the plurality of release agent domains present in the cross section of one toner (toner particle).

Next, a method of calculating the mode of the distribution of the uneven distribution degree B of the release agent domain will be described.
First, the measurement of the uneven distribution degree B of the release agent domain described above is performed for 200 toners (toner particles). The data of the uneven distribution degree B of each release agent domain thus obtained is subjected to statistical analysis processing in a data section from 0 to 0.01, and the distribution of the uneven distribution degree B is determined. The mode of the obtained distribution, that is, the value of the data section that appears most frequently in the distribution of the uneven distribution degree B of the release agent domain is determined. Then, the value of this data section is taken as the mode of the distribution of the uneven distribution degree B of the release agent domain.

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

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

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

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

-Binding resin-
As the binder resin, for example, styrenes (eg, styrene, parachlorostyrene, α-methylstyrene etc.), (meth) acrylates (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) Emissions, a homopolymer of a monomer such as butadiene) and the like, or a vinyl-based resin composed of these monomers with two or more combinations copolymer.
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 with the above-mentioned vinyl resin, or The graft polymer etc. which are obtained by polymerizing a vinyl-type monomer in coexistence are also mentioned.
These binder resins may be used alone or in combination of two or more.

A polyester resin is suitable as the binder resin.
As polyester resin, a well-known polyester resin is mentioned, for example.

  As a polyester resin, the condensation polymer of polyhydric carboxylic acid and polyhydric alcohol is mentioned, for example. In addition, as polyester resin, you may use a commercial item and you may use what was synthesize | combined.

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

Examples of polyhydric alcohols include aliphatic diols (eg ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol etc.), alicyclic diols (eg cyclohexanediol, cyclohexanedimethanol, Hydrogenated bisphenol A etc., aromatic diols (eg ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A etc) may be mentioned. Among these, as the polyhydric alcohol, for example, aromatic diols and alicyclic diols are preferable, and aromatic diols are more preferable.
As the polyhydric alcohol, a trivalent or higher polyhydric alcohol having a crosslinked structure or a branched structure may be used in combination with a diol. Examples of trihydric or higher polyhydric alcohols include glycerin, trimethylolpropane and pentaerythritol.
A polyhydric alcohol may be used individually by 1 type, and may use 2 or more types together.

50 degreeC or more and 80 degrees C or less are preferable, and, as for the glass transition temperature (Tg) of a polyester resin, 50 degrees C or more and 65 degrees C or less are more preferable.
In addition, a glass transition temperature is calculated | required from the DSC curve obtained by differential scanning calorimetry (DSC), and, more specifically, it is described in the determination method of the glass transition temperature of JIS K-1987 "transition temperature measurement method of plastics". It is determined by the "extrapolated glass transition start temperature".

The polyester resin is obtained by a known production method. Specifically, for example, it is obtained by a method in which the polymerization temperature is set to 180 ° C. or more and 230 ° C. or less, the reaction system is reduced in pressure as necessary, and the reaction is performed while removing water and alcohol generated during condensation.
In addition, when the monomer of a raw material does not melt | dissolve or miscible with reaction temperature, you may add and dissolve the solvent of a high boiling point as a solubilizing agent. In this case, the polycondensation reaction is carried out while distilling off the solubilizer. When a monomer with poor compatibility is present in the copolymerization reaction, the monomer with poor compatibility and the acid or alcohol to be polycondensed are condensed in advance, and then it is used together with the main component. 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 More preferable.

-Colorant-
Examples of coloring agents include carbon black, chrome yellow, Hansa yellow, benzidine yellow, Sureren yellow, quinoline yellow, pigment yellow, permanent orange GTR, pyrazolone orange, balkan orange, watch young red, permanent red, permanent 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, chalco oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine blue, pigment green, phthalocyanine green, Various pigments such as malachite green oxalate, or acridine type, xanthene type, Dyes such as benzoquinone dyes, azine dyes, anthraquinone dyes, thioindico dyes, dioxazine dyes, thiazine dyes, azomethine dyes, indigo dyes, phthalocyanine dyes, aniline black dyes, aniline black dyes, polymethine dyes, triphenylmethane dyes, diphenylmethane dyes, and thiazoles dyes Etc.
The coloring agents may be used alone or in combination of two or more.

  As the coloring agent, a surface-treated coloring agent may be used if necessary, and may be used in combination with a dispersing agent. Moreover, a coloring agent may use multiple types together.

  As content of a coloring agent, 1 mass% or more and 30 mass% or less are preferable with respect to the whole toner particle, for example, and 3 mass% or more and 15 mass% or less are more preferable.

-Release agent-
As a mold release agent, for example, hydrocarbon wax; natural wax such as carnauba wax, rice wax, candelilla wax; synthesis such as montan wax or mineral / petroleum wax; ester wax such as fatty acid ester, montanic acid ester And the like. The release agent is not limited to this.

  Among these, hydrocarbon-based waxes (waxes having a hydrocarbon as a skeleton) are preferable as the releasing agent. Hydrocarbon waxes are preferable because they are easy to form a releasing agent domain, and easily exude to the surface of 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, and more preferably 5% by mass or more and 15% by mass or less with respect to the entire toner particles.

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

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

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

In addition, various average particle diameters of toner particles and various particle size distribution indexes are measured using Coulter Multisizer II (manufactured by Beckman Coulter Co., Ltd.), and electrolytic solution is measured using ISOTON-II (manufactured by Beckman Coulter Co.) Ru.
In the measurement, 0.5 mg or more and 50 mg or less of a measurement sample is added to 2 ml of a 5% aqueous solution of surfactant (preferably sodium alkylbenzene sulfonate) as a dispersant. This is added to 100 ml or more and 150 ml or less of electrolyte solution.
The electrolytic solution in which the sample is suspended is dispersed for 1 minute with an ultrasonic disperser, and Coulter Multisizer II, using an aperture of 100 μm as the aperture diameter, the particle size distribution of particles of 2 μm to 60 μm in size. taking measurement. The number of particles to be sampled is 50,000.
With respect to the particle size range (channel) divided based on the particle size distribution to be measured, the cumulative distribution is drawn from the small diameter side in terms of volume and number, and the particle size of cumulative 16% is the volume particle size D16v, number particle size The particle diameter of D16p and cumulative 50% is defined as volume average particle diameter D50v, cumulative number average particle diameter D50p, and particle diameter of 84% cumulative, as volume particle diameter D84v and number particle diameter D84p.
Using these, the volume average particle size distribution index (GSDv) is calculated as (D84 v / D 16 v) ^1/2 , and the number average particle size distribution index (GSD p) is calculated as (D 84 p / D 16 p) ^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 determined by the following equation.
Formula: SF1 = (ML ² / A) × (π / 4) × 100
In the above equation, 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, an optical microscope image of particles dispersed on the slide glass surface is taken into a Luzex image analyzer by a video camera, the maximum length and projection area of 100 particles are determined, and calculation is made according to the above equation, and the average value is determined. 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 , 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 the external additive may be subjected to a hydrophobization treatment. The hydrophobization treatment is performed, for example, by immersing inorganic particles in a hydrophobization treatment agent. The hydrophobizing agent is not particularly limited, and examples thereof include silane coupling agents, silicone oils, titanate coupling agents, aluminum coupling agents and the like. These may be used alone or in combination of two or more.
The amount of the hydrophobic treatment agent is usually, for example, 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the inorganic particles.

  As external additives, resin particles (resin particles such as polystyrene, polymethyl methacrylate (PMMA), melamine resin, etc.), cleaning activators (for example, metal salts of higher fatty acids represented by zinc stearate, fluorine-based polymer Particles) and the like.

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

(Method of manufacturing toner)
Next, a method of manufacturing the toner according to the present embodiment will be described.
The toner according to the exemplary embodiment is obtained by externally adding an external additive to toner particles after producing the toner particles.

The toner particles may be produced by any of dry production method (for example, kneading and pulverization method and the like) and wet production method (for example, aggregation and coalescence method, suspension polymerization method, dissolution and suspension method and the like). There are no particular limitations on the method for producing toner particles, and any known method may be employed.
Among these, toner particles are preferably obtained by an aggregation and coalescence method.

  In particular, from the viewpoint of obtaining toner (toner particles) satisfying the distribution characteristics of the uneven distribution degree B of the releasing agent domain described above, the toner particles are preferably produced by the following aggregation and coalescence method.

Specifically, the step of preparing each dispersion (dispersion liquid preparation step),
Obtained by mixing the first resin particle dispersion in which the first resin particles serving as the binder resin are dispersed, and the colorant particle dispersion in which colorant particles (hereinafter also referred to as “colorant particles”) are dispersed. Aggregating each particle in the dispersion liquid to form first aggregated particles (first aggregated particle forming process);
After the first aggregated particle dispersion liquid in which the first aggregated particles are dispersed is obtained, the second resin particles as a binder resin and the particles of the releasing agent (hereinafter also referred to as “releasing agent particles”) are dispersed The dispersion is sequentially added to the first aggregated particle dispersion while the concentration of the release agent particles in the mixed dispersion is gradually increased, and the second resin particles and the release agent particles are further added to the surface of the first aggregated particles. Coagulating to form a second aggregated particle (second aggregated particle forming process);
Heating the second aggregated particle dispersion in which the second aggregated particles are dispersed to fuse and unite the second aggregated particles to form toner particles (fusion / combination step);
Preferably, toner particles are produced.

  The method of producing toner particles is not limited to the above. For example, the resin particle dispersion and the colorant particle dispersion are mixed, and each particle is aggregated in the obtained mixed dispersion. Next, in the aggregation process, the release agent particle dispersion is added to the mixed dispersion while the addition rate is gradually increased or the concentration of the release agent particles is increased, and the aggregation of each particle is further advanced. To form agglomerated 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 preparation step-
First, each dispersion used in the aggregation and coalescence method is prepared. Specifically, a first resin particle dispersion liquid in which a first resin particle to be a binder resin is dispersed, a colorant particle dispersion liquid in which a colorant particle is dispersed, and a second resin particle to be a binder resin are dispersed. The second resin particle dispersion and the release agent particle dispersion in which the release agent particles are dispersed are prepared.
In each dispersion preparation step, the first resin particles and the second resin particles will be described as "resin particles".

  Here, the resin particle dispersion 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 aqueous media.
Examples of the aqueous medium include water such as distilled water and ion exchange water, and alcohols. These may be used alone or in combination of two or more.

As surfactant, for example, anionic surfactant such as sulfate ester type, sulfonate type, phosphoric ester type, soap type; cationic surfactant such as amine salt type, quaternary ammonium salt type; polyethylene glycol And nonionic surfactants such as alkylphenol ethylene oxide adducts and polyhydric alcohols. Among these, anionic surfactants and cationic surfactants are particularly mentioned. Nonionic surfactants may be used in combination with anionic surfactants or cationic surfactants.
The surfactant may be used alone or in combination of two or more.

In the resin particle dispersion, as a method of dispersing the resin particles in a dispersion medium, for example, general dispersion methods such as a rotational shear type homogenizer, a ball mill having media, a sand mill, a dyno mill and the like can be mentioned. Further, depending on the type of resin particles, the resin particles may be dispersed in the resin particle dispersion using, for example, a phase inversion emulsification method.
In the phase inversion emulsification method, the resin to be dispersed is dissolved in a hydrophobic organic solvent in which the resin is soluble, and a base is added to the organic continuous phase (O phase) to neutralize it, and then a water medium is obtained. Method of converting resin from W / O to O / W (so-called phase inversion) by introducing (W phase) to discontinuous phase and dispersing resin in the form of particles in water medium It is.

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

  As content of the resin particle contained in a resin particle dispersion liquid, 5 mass% or more and 50 mass% or less are preferable, for example, 10 mass% or more and 40 mass% or less are more preferable.

  In the same manner as the resin particle dispersion, for example, a colorant particle dispersion and a releasing agent particle dispersion are also prepared. That is, with respect to the volume average particle diameter of the particles in the resin particle dispersion, the dispersion medium, the dispersion method, and the content of the particles, the colorant particles dispersed in the colorant particle dispersion and the releasing agent particle dispersion The same applies to the releasing agent particles to be dispersed.

-1st aggregation particle formation process-
Next, the first resin particle dispersion and the colorant particle dispersion are mixed.
Then, in this mixed dispersion, the first resin particles and the colorant particles are hetero-aggregated to form first aggregated particles including the first resin particles and the colorant particles.

Specifically, for example, after adding an aggregating agent 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 dispersed in a mixed dispersion by heating to the temperature of the glass transition temperature of the first resin particle (specifically, for example, the glass transition temperature of the first resin particle-30 ° C or more and the glass transition temperature-10 ° C or less) Are aggregated to form first aggregated particles.
In the first aggregated particle forming step, for example, the above coagulant is added at room temperature (eg, 25 ° C.) while stirring the mixed dispersion with a rotary shear type homogenizer, and the pH of the mixed dispersion is made acidic (eg, pH is 2 or more) After adjusting to 5 or less and adding a dispersion stabilizer as needed, you may perform the said heating.

As the aggregating agent, for example, a surfactant having an opposite polarity to the surfactant used as a dispersing agent added to the mixed dispersion, an inorganic metal salt, and a divalent or higher metal complex can be mentioned. In particular, when a metal complex is used as the aggregating agent, the amount of surfactant used is reduced, and the charging characteristics are improved.
Additives that form a complex or similar bond with the metal ion of the flocculant may be used if desired. As the additive, a chelating agent is preferably used.

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

-Second aggregated particle formation 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 made of the release agent particles in the mixed dispersion liquid. The concentration is gradually increased while sequentially adding to the first aggregated particle dispersion.
The second resin particles may be the same as or different from the first resin particles.

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 the target particle size, the concentration of the release agent particles is gradually increased in the first aggregated particle dispersion liquid, A mixed dispersion in which the second resin particles and the release agent particles are dispersed is added, and the dispersion 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 setting the pH of the dispersion to, for example, about 6.5 to 8.5.

  Through this process, aggregated particles in which the second resin particles and the release agent particles are attached 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 are formed on the surface of the first aggregated particles. At this time, the mixed dispersion in which the second resin particles and the release agent particles are dispersed is sequentially added to the first aggregated particle dispersion while the concentration of the release agent particles in the mixed dispersion is gradually increased. On the surface of the first aggregated particles, the concentration (presence ratio) of the release agent particles gradually increases toward the outside in the particle diameter direction, and the aggregates of the second resin particles and the release agent particles adhere.

  Here, as a method of adding the mixed dispersion, it is preferable to use a power feed addition method. 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, the method of adding the mixed dispersion 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 indicates a first aggregated particle dispersion, 312 indicates a second resin particle dispersion, and 313 indicates a release agent particle dispersion.

  The apparatus shown in FIG. 3 contains a first accommodation tank 321 in which the first agglomerated particles are dispersed to contain the first agglomerated particle dispersion, and a second resin particle dispersion in which the second resin particles are dispersed. And a third containing tank 323 containing the releasing agent particle dispersion liquid in which the releasing agent particles are dispersed.

The first storage tank 321 and the second storage tank 322 are connected by a first liquid transfer pipe 331. A first liquid delivery pump 341 intervenes in the middle of the path of the first liquid delivery pipe 331. 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 by driving of the first liquid transfer pump 341.
In the first storage tank 321, a first stirring device 351 is disposed. When the dispersion contained in the second storage tank 322 is fed to the dispersion contained in the first storage tank 321 by the driving of the first stirring device 351, each dispersion is stirred in the first storage tank 321. Be mixed.

The second storage tank 322 and the third storage tank 323 are connected by a second liquid transfer pipe 332. In the middle of the path of the second liquid delivery pipe 332, a second liquid delivery pump 342 is interposed. By driving the second liquid feed pump 342, the dispersion liquid stored in the third storage tank 323 is sent to the dispersion liquid stored in the second storage tank 322 through the second liquid feed pipe 332.
In the second storage tank 322, a second stirring device 352 is disposed. When the dispersion contained in the third storage tank 323 is fed to the dispersion contained in the second storage tank 322 by the drive of the second stirring device 352, each dispersion is stirred in the second storage tank 322 and Be mixed.

  In the apparatus shown in FIG. 3, first, the first aggregated particle forming step is carried out in the first storage tank 321 to prepare a first aggregated particle dispersion, and the first aggregated particle dispersion is stored in the first storage tank 321. To accommodate. The first aggregated particle dispersion liquid may be stored in the first storage tank 321 after the first aggregated particle formation process is performed in another tank to produce the first aggregated particle dispersion liquid.

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, the respective dispersions are stirred and mixed in the first storage tank 321 by driving of the first stirring device 351.
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, the respective dispersions are stirred and mixed in the second storage tank 322 by driving of the second stirring device 352.

  At this time, the release agent particle dispersion liquid is sequentially sent to the second resin particle dispersion liquid stored in the second storage tank 322, and the concentration of the release agent particles gradually increases. For this reason, a mixed dispersion in which the second resin particles and the release agent particles are dispersed is stored in the second storage tank 322, and the mixed dispersion is stored in the first storage tank 321. 1) It is sent to the aggregated particle dispersion. Then, the liquid transfer of the mixed dispersion is performed continuously while the concentration of the releasing agent particle dispersion in the mixed dispersion increases.

Thus, by utilizing the power feed addition method, a mixed dispersion in which the second resin particles and the release agent particles are dispersed in the first aggregated particle dispersion while gradually increasing the concentration of the release agent particles is obtained. It can be added.
Then, in the power feed addition method, the distribution characteristics of the release agent domain of the toner are adjusted by adjusting the liquid transfer start timing and the liquid transfer rate of each of the dispersions stored in the second storage tank 322 and the third storage tank 323. Is adjusted. Also, in the power feed addition method, the distribution of the release agent domain of the toner is also obtained by adjusting the liquid transfer rate during the liquid transfer of the dispersions stored in the second storage tank 322 and the third storage tank 323. Characteristics are adjusted.

  Specifically, for example, the mode of the distribution of the uneven distribution degree B of the release agent domain is adjusted according to the time when the release agent particle dispersion liquid is transferred from the third storage tank 323 to the second storage tank 322. Ru. More specifically, for example, before the end 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 in the second storage tank 322 does not increase beyond that point. As a result, the mode of the distribution of the uneven distribution degree B of the release agent domain is reduced.

  Also, for example, the skewness of the distribution of the uneven distribution degree B of the release agent domain is determined by the timing at which each dispersion is fed from the second storage tank 322 and the third storage tank 323 and from the second storage tank 322 to the first storage tank. It adjusts by the liquid feeding speed which sends a dispersion liquid to 321. More specifically, for example, the liquid transfer start timing of the release agent particle dispersion from the third storage tank 323 and the liquid transfer start timing of the dispersion from the second storage tank 322 are advanced, and from the second storage tank 322 When the liquid transfer speed of the dispersion liquid is decreased, the release agent particles are arranged from the inside to the outside of the particles in the formed aggregated particles. Thereby, the skewness of the distribution of the uneven distribution degree B of the release agent domain is increased.

  Further, for example, the kurtosis of the distribution of the uneven distribution degree B of the release agent domain is adjusted by changing the liquid transfer speed of the release agent particle dispersion liquid from the third storage tank 323 during liquid transfer. More specifically, for example, when the release agent particle dispersion liquid is sent from the third storage tank 323, if only the liquid sending speed is increased, the release of the dispersion liquid in the second storage tank 322 from that time The concentration of agent particles is increased. For this reason, in the aggregated particles to be formed, in a radial direction of the particles, a large amount of release agent particles is disposed in a certain region (a certain depth portion). Thereby, the kurtosis of the distribution of the uneven distribution degree B of the release agent domain is increased.

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

  As described above, the second aggregated particles are obtained in which the second resin particles and the release agent particles adhere to each other on the surface of the first aggregated particles.

-Fusion and coalescence process-
Next, with respect to the second aggregated particle dispersion in which the second aggregated particles are dispersed, for example, the glass transition temperature or more of the first and second resin particles (for example, 10 or more than the glass transition temperature of the first and second resin particles) By heating to a temperature higher by 30.degree. C.) to fuse and unite the second aggregated particles to form toner particles.

Through the above steps, toner particles are obtained.
In addition, 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 to be the binder resin are dispersed, Further, the step of forming a third aggregated particle by further mixing and aggregating so as to further attach the third resin particle to the surface of the second aggregated particle, and a third aggregated particle dispersion liquid in which the third aggregated particle is dispersed Then, the toner particles may be manufactured through the steps of heating them to fuse and unite the second aggregated particles to form core / shell structured toner particles.
By this operation, in the obtained toner particles (toner), the mode value of the distribution of the uneven distribution degree B of the release agent domain becomes less than 1.00.

Here, after completion of the coalescence and coalescence step, toner particles formed in the solution are subjected to a known washing step, solid-liquid separation step and drying step to obtain toner particles in a dried state.
In the washing step, it is preferable to carry out substitution washing with ion exchange water sufficiently from the viewpoint of chargeability. The solid-liquid separation step is not particularly limited, but it is preferable to apply suction filtration, pressure filtration, etc. from the viewpoint of productivity. Further, the drying step is also not particularly limited, but in view of productivity, lyophilization, flash jet drying, fluid drying, vibration-type fluid drying, etc. may be performed.

  The toner according to the exemplary embodiment is manufactured, for example, by adding an external additive to the obtained toner particles in a dry state and mixing them. The mixing may be performed by, for example, a V blender, a Henschel mixer, a Loedige mixer, or the like. Furthermore, if necessary, coarse particles of toner may be removed using a vibration divider, an air flow divider, or the like.

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

There is no restriction | limiting in particular as a carrier, A well-known carrier is mentioned. As the carrier, for example, a coated carrier obtained by coating a coating resin on the surface of a core material made of magnetic powder; a magnetic powder dispersion type carrier in which magnetic powder is dispersed / blended in a matrix resin; porous magnetic powder is impregnated with resin Resin impregnated carriers; and the like.
The magnetic powder-dispersed carrier and the resin-impregnated carrier may be a carrier in which the constituent particles of the carrier are used as a core material and the core particles are coated with a coating resin.

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

As coating resin and matrix resin, for example, polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic acid copolymer Examples thereof include polymers, straight silicone resins comprising an organosiloxane bond or modified products thereof, fluoro resins, polyesters, polycarbonates, phenol resins, epoxy resins and the like.
The coating resin and the matrix resin may contain other additives such as conductive particles.
Examples of conductive particles include particles of metals such as gold, silver and copper, carbon black, titanium oxide, zinc oxide, tin oxide, barium sulfate, aluminum borate, potassium titanate and the like.

Here, in order to coat the surface of the core material with a coating resin, a coating resin, and a method of coating with a solution for forming a coating layer in which various additives are dissolved in an appropriate solvent, if necessary, can be mentioned. The solvent is not particularly limited, and may be selected in consideration of the coating resin to be used, coating suitability and the like.
As a specific resin coating method, an immersion method in which the core material is immersed in a solution for forming a coating layer, a spray method in which a solution for forming a coating layer is sprayed on the surface of the core material, and a state in which the core material is suspended by flowing air. A fluid bed method of spraying a solution for forming a coating layer, a kneader coater method of mixing a core material of a carrier and a solution for forming a coating layer in a kneader coater, and removing a solvent may, for example, be mentioned.

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

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

  The image forming apparatus according to the present embodiment includes 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 present embodiment. Developing the electrostatic charge image formed on the surface of the image carrier as a toner image with an image developer, and transferring the toner image formed on the surface of the image carrier onto the surface of the recording medium; And an image forming method (image forming method according to the present embodiment) including the fixing step of fixing the toner image transferred to the surface of the recording medium.

The image forming apparatus according to the present embodiment directly transfers the toner image formed on the surface of the image carrier to the recording medium; the toner image formed on the surface of the image carrier is an intermediate transfer member An intermediate transfer type device that performs 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; cleans the surface of the image carrier before charging after transferring the toner image A known image forming apparatus such as an apparatus provided with a cleaning means; an apparatus provided with a diselectrification means for diselectrifying the surface of the image holding member before electrification after transferring a toner image is applied.
In the case of an intermediate transfer type apparatus, for example, an intermediate transfer member to which a toner image is transferred on the surface, and a primary transfer on which the toner image formed on the surface of the image carrier is primarily transferred to the surface of the intermediate transfer member. A configuration is applied that includes: means; and secondary transfer means for secondary transfer of the toner image transferred to the surface of the intermediate transfer member to the surface of the recording medium.

  In the image forming apparatus according to the present embodiment, for example, the part including the developing unit may have a cartridge structure (process cartridge) which is detached from the image forming apparatus. As the process cartridge, for example, a process cartridge including a developing unit containing the electrostatic charge image developer according to the present embodiment is suitably used.

  Hereinafter, although an example of the image forming apparatus according to the present embodiment is shown, the present invention is not limited to this. 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 view showing an image forming apparatus according to the present embodiment.
The image forming apparatus shown in FIG. 1 is an electrophotographic first to output an image of each color of yellow (Y), magenta (M), cyan (C) and black (K) based on color separated image data. The fourth image forming units 10Y, 10M, 10C, and 10K (image forming means) are provided. These image forming units (hereinafter sometimes referred to simply as “units”) 10Y, 10M, 10C, and 10K are arranged side by side at a predetermined distance from each other in the horizontal direction. The units 10Y, 10M, 10C, and 10K may be process cartridges that can be detached 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 is extended through the units. The intermediate transfer belt 20 is wound around a drive roll 22 and a support roll 24 in contact with the inner surface of the intermediate transfer belt 20, which are spaced apart from each other in the left to right direction in FIG. The vehicle travels 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 a tension is applied to the intermediate transfer belt 20 wound around both. Further, 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.
Also, yellow, magenta, cyan and black contained in the toner cartridges 8Y, 8M, 8C and 8K in the developing devices (developing means) 4Y, 4M, 4C and 4K of the units 10Y, 10M, 10C and 10K, respectively. The toner including four color toners is supplied.

  Since the first to fourth units 10Y, 10M, 10C, and 10K have the same configuration, here, the first unit that forms the yellow image disposed on the upstream side in the traveling direction of the intermediate transfer belt The 10Y will be described as a representative. The second to fourth reference numerals are attached to parts equivalent to the first unit 10Y by substituting magenta (M), cyan (C) and black (K) instead of yellow (Y). The description of the units 10M, 10C, and 10K is omitted.

The first unit 10Y has a photoreceptor 1Y acting as an image carrier. A charging roll (an example of a charging unit) 2Y for charging the surface of the photosensitive member 1Y to a predetermined potential around the photosensitive member 1Y and a laser beam 3Y based on an image signal obtained by color separation of the charged surface Exposure apparatus (an example of an electrostatic charge image forming unit) 3 for forming an electrostatic charge image, a developing apparatus (an example of a development unit) 4Y for developing an electrostatic charge image by supplying toner charged to the electrostatic charge image Primary transfer roll 5Y for transferring a toner image onto intermediate transfer belt 20 (an example of a primary transfer means), and photoreceptor cleaning device (an example of a cleaning means) 6Y for removing toner remaining on the surface of photoreceptor 1Y after primary transfer. Are arranged in order.
The primary transfer roll 5Y is disposed inside the intermediate transfer belt 20, and is provided at a position facing the photoreceptor 1Y. Further, a bias power supply (not shown) for applying a primary transfer bias is connected to each of the primary transfer rolls 5Y, 5M, 5C, and 5K. Each bias power supply varies the transfer bias applied to each primary transfer roll under control of a control unit (not shown).

Hereinafter, an operation of forming a yellow image in the first unit 10Y will be described.
First, prior to operation, the surface of the photosensitive member 1Y is charged to a potential of -600 V to -800 V by the charging roll 2Y.
The photoreceptor 1 </ ^b > Y is formed by laminating a photosensitive layer on a conductive (for example, volume resistivity at 20 ° C .: 1 × 10 ⁻⁶ Ωcm or less) substrate. This photosensitive layer usually has a high resistance (resistance of a general resin), but has the property that the specific resistance of the portion irradiated with the laser beam changes when the laser beam 3Y is irradiated. Therefore, the laser beam 3Y is output to the charged surface of the photosensitive member 1Y through the exposure device 3 in accordance with 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 photoreceptor 1Y, whereby an electrostatic charge image of a yellow image pattern is formed on the surface of the photoreceptor 1Y.

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

  In the developing device 4Y, for example, an electrostatic charge image developer containing at least a yellow toner and a carrier is accommodated. The yellow toner is frictionally charged by being stirred inside the developing device 4Y, and has a charge of the same polarity (negative polarity) as the charged charge on the photosensitive member 1Y, and the developer roll (the developer holding member One example is held on top. Then, as the surface of the photosensitive member 1Y passes through the developing device 4Y, the yellow toner is electrostatically attached to the electrostatic latent image portion on the surface of the photosensitive member 1Y, and the latent image is developed by the yellow toner . The photoreceptor 1Y on which the yellow toner image is formed is subsequently traveled at a predetermined speed, and the toner image developed on the photoreceptor 1Y is conveyed to a predetermined primary transfer position.

When the yellow toner image on the photosensitive member 1Y is conveyed to the primary transfer, a primary transfer bias is applied to the primary transfer roll 5Y, and an electrostatic force from the photosensitive member 1Y toward the primary transfer roll 5Y is applied to the toner image. The toner image on 1 Y is transferred onto the intermediate transfer belt 20. The transfer bias applied at this time is the (+) polarity opposite to the polarity (−) of the toner, and is controlled to +10 μA by the control unit (not shown) in the first unit 10Y, for example.
On the other hand, the toner remaining on the photosensitive member 1Y is removed and collected by the photosensitive member 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.
Thus, the intermediate transfer belt 20 to which the yellow toner image is transferred in the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of the respective colors are superimposed and transferred in multiples. Ru.

  The intermediate transfer belt 20 on which toner images of four colors are multiply transferred through the first to fourth units is disposed on the intermediate transfer belt 20 and the image holding surface side of the intermediate transfer belt 20 and the support roll 24 in contact with the inner surface of the intermediate transfer belt. It leads to the secondary transfer part comprised from the secondary transfer roll (an example of a secondary transfer means) 26 which was carried out. On the other hand, recording paper (an example of a recording medium) P is fed at a predetermined timing to a gap where the secondary transfer roll 26 and the intermediate transfer belt 20 contact via a supply mechanism, and the secondary transfer bias is a support roll. 24 is applied. The transfer bias applied at this time is the same as the polarity (−) of the toner (−), and the electrostatic force from the intermediate transfer belt 20 to the recording paper P is applied to the toner image. Is transferred onto the recording paper P. The secondary transfer bias at this time is determined according to the resistance detected by a resistance detection unit (not shown) that detects the resistance of the secondary transfer portion, and is voltage controlled.

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

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

<Process cartridge / Toner cartridge>
The process cartridge according to the present embodiment will be described.
The process cartridge according to the present embodiment contains the electrostatic charge image developer according to the present embodiment, and develops the electrostatic charge image formed on the surface of the image carrier as the toner image by the electrostatic charge image developer. The process cartridge is detachably mounted to an image forming apparatus.

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

  Hereinafter, although an example of the process cartridge according to the present embodiment is shown, the present invention is not limited to this. 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 view showing a process cartridge according to the present embodiment.
The process cartridge 200 shown in FIG. 2 is provided around the photosensitive member 107 (an example of an image carrier) and the photosensitive member 107 by, for example, a housing 117 provided with a mounting rail 116 and an opening 118 for exposure. A charging roller 108 (an example of the charging means), a developing device 111 (an example of the developing means), and a photosensitive member cleaning device 113 (an example of the cleaning means) are integrally combined and held. 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 a recording sheet (recording medium). An example is shown.

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

  Note that the image forming apparatus shown in FIG. 1 is an image forming apparatus having a configuration in which toner cartridges 8Y, 8M, 8C, 8K are detachably mounted, and developing devices 4Y, 4M, 4C, 4K And a toner supply pipe (not shown). Further, when the amount of toner contained in the toner cartridge is reduced, the toner cartridge is replaced.

  Hereinafter, the present embodiment will be described in more detail by way of examples and comparative examples, but the present embodiment is not limited to these examples. In addition, "part" means "mass part" unless there is particular notice.

<Preparation of Resin Particle Dispersion>
[Preparation of Resin Particle Dispersion (1)]
Terephthalic acid: 30 parts by mol Fumaric acid: 70 parts by mol Bisphenol A ethylene oxide adduct: 5 parts by mol Bisphenol A propylene oxide adduct: 95 parts by mol Stirring apparatus, nitrogen introducing pipe, temperature sensor, rectification column The above material was charged into a 5-liter flask equipped with a volume of 1 hour, the temperature was raised to 210 ° C., and 1 part of titanium tetraethoxide was added to 100 parts of the material. The temperature was raised to 230 ° C. taking 0.5 hour while distilling off the water formed, and 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 mg KOH / g and a glass transition temperature of 59 ° C. was synthesized.

40 parts of ethyl acetate and 25 parts of 2-butanol are put in a container equipped with a temperature control means and a nitrogen substitution means to make a mixed solvent, and 100 parts of polyester resin (1) is gradually put in and dissolved. A 10% by mass aqueous ammonia solution (equivalent to a 3-fold amount in molar ratio to the acid value of the resin) was added and stirred for 30 minutes.
Next, the inside of the container was replaced with dry nitrogen, and the temperature was maintained at 40 ° C., and 400 parts of ion exchanged water was dropped at a rate of 2 parts / minute while stirring the mixture to perform emulsification. After completion of the dropwise addition, the emulsion is returned to room temperature (20 ° C. to 25 ° C.), and ethyl acetate and 2-butanol are reduced to 1,000 ppm or less by bubbling with dry nitrogen for 48 hours while stirring to reduce volume average particle size. The resin particle dispersion liquid which the resin particle of diameter 200 nm disperse | distributed was obtained. Ion-exchanged water was added to the resin particle dispersion to adjust the solid content to 20% by mass to obtain a resin particle dispersion (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 LA 5380): 70 parts Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd. product Neogen RK): 5 parts Ion exchange water: 200 Part The above materials were mixed and dispersed for 10 minutes using a homogenizer (UltraTarax T50 manufactured by IKA Corporation). Ion-exchanged water was added so that the solid content in the dispersion became 20% by mass, to obtain a colorant particle dispersion (1) in which colorant particles having a volume average particle diameter of 190 nm were dispersed.

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

Example 1
[Preparation of Toner Particles]
A round stainless steel flask and container A are connected by a tube pump A, the liquid contained in the container A is sent to the flask by driving the tube pump A, and the container A and container B are connected by a tube pump B. The apparatus (refer FIG. 3) which sends the accommodation liquid accommodated in the container B to the container A by drive of the tube pump B was prepared. And the following operations were implemented using this apparatus.

Resin particle dispersion (1): 500 parts Colorant particle dispersion (1): 40 parts Anionic surfactant (TaycaPower): 2 parts The above material is put in a round stainless steel flask, 0.1N After the pH was adjusted to 3.5 by adding nitric acid, 30 parts of nitric acid aqueous solution containing 10% by mass of polyaluminum chloride was added. Subsequently, after dispersing at 30 ° C. using a homogenizer (UltraTarax T50 manufactured by IKA Co., Ltd.), the particle diameter of aggregated particles is allowed to grow while raising the temperature at a pace of 1 ° C./30 minutes in a heating oil bath. The
On the other hand, 150 parts of the resin particle dispersion (1) was placed in a container A of a polyester bottle, and 25 parts of the release agent particle dispersion (1) was placed in the same container B. Next, the liquid feeding speed of the tube pump A is set to 0.70 part / min, the liquid feeding speed of the tube pump B is set to 0.14 part / min, and the inside of the round stainless steel flask during aggregation particle formation is set. When the temperature reached 37.0 ° C., tube pumps A and B were driven to start feeding of each dispersion. Thus, the mixed dispersion in which the resin particles and the release agent particles were dispersed was transferred from the container A to the round stainless steel flask in which the aggregated particles are being formed, while gradually increasing the concentration of the release agent particles.
Then, liquid transfer of each dispersion to the flask was completed, and the temperature was maintained at 48 ° C. in the flask for 30 minutes to form second aggregated particles.

  Thereafter, 50 parts of the resin particle dispersion (1) is slowly added, and maintained for 1 hour, and the pH is adjusted to 8.5 by addition of a 0.1 N aqueous solution of sodium hydroxide; Heat to ° C and hold for 5 hours. Thereafter, it is cooled to 20 ° C. at a rate of 20 ° C./minute, filtered, sufficiently washed with ion exchange water, and dried to obtain toner particles (1) having a volume average particle diameter of 6.0 μm.

Preparation of Toner
100 parts of toner particles (1) and 0.7 parts of dimethyl silicone oil-treated silica particles (RY200 manufactured by Nippon Aerosil Co., Ltd.) are mixed using a Henschel mixer (peripheral speed 30 m / sec, 3 minutes) to obtain toner (1) I 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 The dispersion was dispersed to prepare a dispersion, and this dispersion, together with ferrite particles, was placed in a vacuum degassing type kneader and dried under reduced pressure with stirring 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 preparation of the toner particles (1), the feed rate of the tube pump A is set to 0.55 parts / minute, the feed rate of the tube pump B is set to 0.11 parts / minute, and the temperature in the flask is 33 After reaching 0 ° C., toner particles (2) were obtained in the same manner as in Example 1 except that tube pumps A and B were driven. 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 preparation of toner particles (1), the tube pump A feed rate is set to 0.80 part / minute, the tube pump B feed rate is set to 0.16 parts / minute, and the temperature in the flask is 35 After reaching 0 ° C., toner particles (3) were obtained in the same manner as in Example 1 except that tube pumps A and B were driven. The obtained toner particles (3) had a volume average particle size 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 preparation of the toner particles (1), the feed rate of the tube pump A is set to 0.58 parts / minute, the feed rate of the tube pump B is set to 0.11 parts / minute, and the temperature in the flask is 39 After reaching 0 ° C., toner particles (4) were obtained in the same manner as in Example 1 except that tube pumps A and B were driven. The obtained toner particles (4) had a volume average particle size 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 preparation of the toner particles (1), the feed rate of the tube pump A is set to 0.84 parts / minute, the feed rate of the tube pump B is set to 0.17 parts / minute, and the temperature in the flask is 41 After reaching 0 ° C., toner particles (5) were obtained in the same manner as in Example 1 except that tube pumps A and B were driven. The obtained toner particles (5) had a volume average particle size 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 preparation of the toner particles (1), the feed rate of the tube pump A is set to 0.55 parts / minute, the feed rate of the tube pump B is set to 0.11 parts / minute, and the temperature in the flask is 30 After reaching 0 ° C., toner particles (C1) were obtained in the same manner as in Example 1 except that tube pumps A and B were driven. 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 preparation of the toner particles (1), the liquid feeding speed of the tube pump A is set to 0.84 parts / minute, the liquid feeding speed of the tube pump B is set to 0.17 parts / minute, and the temperature in the flask is 33 After reaching 0 ° C., toner particles (C2) were obtained in the same manner as in Example 1 except that tube pumps A and B were driven. 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 preparation of the toner particles (1), the feed rate of the tube pump A is set to 0.51 part / minute, the feed rate of the tube pump B is set to 0.10 part / minute, and the temperature in the flask is 31 After reaching 0 ° C., toner particles (C3) were obtained in the same manner as in Example 1 except that tube pumps A and B were driven. 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 preparation of the toner particles (1), the feeding speed of the tube pump A is set to 0.90 part / minute, the feeding speed of the tube pump B is set to 0.19 part / minute, and the temperature in the flask is 35 After reaching 0 ° C., toner particles (C4) were obtained in the same manner as in Example 1 except that tube pumps A and B were driven. The resulting toner particles (C4) had a volume average particle size 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 preparation of the toner particles (1), the feed rate of the tube pump A is set to 0.50 parts / minute, the feed rate of the tube pump B is set to 0.10 parts / minute, and the temperature in the flask is 38 After reaching 0 ° C., toner particles (C5) were obtained in the same manner as in Example 1 except that tube pumps A and B were driven. The obtained toner particles (C5) had a volume average particle size 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 preparation of toner particles (1), the tube pump A feed rate is set to 0.89 parts / minute, the tube pump B feed rate is set to 0.19 parts / minute, and the temperature in the flask is 42 After reaching 0 ° C., toner particles (C6) were obtained in the same manner as in Example 1 except that tube pumps A and B were driven. The obtained toner particles (C6) had a volume average particle size 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 preparation of toner particles (1), the tube pump A feed rate is set to 0.75 part / minute, the tube pump B feed rate to 0.11 part / minute, and the temperature in the flask is 37 The tube pumps A and B are driven from the time when the temperature reaches 0 ° C., and when the temperature in the flask reaches 40 ° C., the liquid transfer speed of the tube pump B is changed to 0.19 parts / 1 min. 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 preparation of toner particles (1), the tube pump A feed rate is set to 0.75 parts / minute, the tube pump B feed rate is set to 0.14 parts / minute, and the temperature in the flask is 35 . Other than operating tube pumps A and B from the time of reaching 0 ° C and changing the liquid transfer speed of tube pump B to 0.10 part / 1 minute when the temperature in the flask reaches 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 preparation of toner particles (1), the tube pump A feed rate is set to 0.75 part / minute, the tube pump B feed rate is set to 0.11 part / minute, and the temperature in the flask is 35 The tube pumps A and B are driven from the time when the temperature is reached, and when the temperature in the flask reaches 40 ° C., the liquid delivery speed of the tube pump B is changed to 0.22 parts / minute, except In the same manner as in Example 1, toner particles (R1) were obtained. The obtained toner particles (R1) had a volume average particle size 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 preparation of toner particles (1), the tube pump A feed rate is set to 0.75 parts / minute, the tube pump B feed rate is set to 0.14 parts / minute, and the temperature in the flask is 35 The tube pumps A and B are driven from the time when the temperature is reached, and when the temperature in the flask reaches 39 ° C., the liquid delivery speed of the tube pump B is changed to 0.08 parts / minute, except In the same manner as in Example 1, toner particles (R2) were obtained. The obtained toner particles (R2) had a volume average particle size 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 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 gloss unevenness]
The following operations and image formation were performed under the environment of temperature 25 ° C./humidity 60%.
As an image forming apparatus for forming an evaluation image, an apparatus modified from Fuji Xerox Co., Ltd. 700 Digital Color Press so as to output an unfixed image up to the end of the sheet is prepared, and a developer is put in a developing device to supply toner. (The same toner as the toner contained in the developer) was placed in the toner cartridge. Subsequently, on the embossed paper (Rezac 66 white manufactured by Fuji Xerox Co., Ltd., basis weight 151 g / m ² ), a full-color image with no leading edge margin is formed with a secondary color 200% density, and the fixing temperature is 180 ° C. The process speed was set to 220 mm / sec, and 100 sheets were continuously output. The following evaluation was performed on the obtained first and 100th images.

-Evaluation of peelability-
With respect to the obtained first and 100th images, the state of the leading edge of the sheet was observed and evaluated according to the following criteria.
A: Peeling failure has not occurred, and the condition of the leading edge of the paper is also good.
B: Peeling failure is not generated, and the leading edge of the paper is slightly curled.
C: Roughening of the tip of the image due to poor peeling occurred.
D: Unable to peel off, paper wrapping occurs.

-Evaluation of uneven gloss-
The 60-degree gloss was measured on the obtained first and 100th images using a portable gloss meter (BYK Gardner Micro Trigloss, manufactured by Toyo Seiki Co., Ltd.). Measure at random 10 times at a total of 5 points at the front end left end / front end right end / rear end left end / rear end right end / center of the image, and calculate the standard deviation σ for the obtained 50 gross value data It was used as an indicator 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, better results were obtained for evaluation of peeling failure and uneven gloss compared to the comparative example.
In particular, in Examples 6 to 7 in which the kurtosis of the distribution of the uneven distribution degree B of the release agent domain is in the range of -0.20 or more and +1.50 or less, peeling defects and gloss unevenness are compared with Reference Examples 1 and 2. It can be seen that good results were obtained for both evaluations of.

1Y, 1M, 1C, 1K photoconductors (an example of an image carrier)
2Y, 2M, 2C, 2K charging rolls (an example of charging means)
3 Exposure device (an example of electrostatic charge image forming means)
3Y, 3M, 3C, 3K laser beams 4Y, 4M, 4C, 4K developing devices (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 the cleaning means)
8Y, 8M, 8C, 8K Toner Cartridges 10Y, 10M, 10C, 10K Image Forming Unit 20 Intermediate Transfer Belt (Example of Intermediate Transfer Member)
22 Drive roll 24 Support roll 26 Secondary transfer roll (an example of secondary transfer means)
30 Intermediate Transfer Cleaning Device 107 Photoconductor (Example of Image Carrier)
108 Charging roll (an example of charging means)
109 Exposure apparatus (an example of electrostatic charge image forming means)
111 Development device (an example of development means)
112 Transfer device (an example of transfer means)
113 Photosensitive member cleaning device (an example of the cleaning means)
115 Fixing device (an example of fixing means)
116 Mounting rail 118 Opening 117 for exposure Case 200 Process cartridge 300 Recording paper (an example of recording medium)
P recording paper (an example of recording medium)

Claims (6)

Containing binder resin, coloring agent, and mold release agent,
It has a sea-island structure having a sea part containing the binder resin and an island part containing the release agent,
The content of the release agent is 1% by mass or more and 20% by mass or less with respect to the entire toner,
The mode of the distribution of the uneven distribution B of the island portion containing the mold release agent shown 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 -0 And the island portion including the release agent is distributed with a gradient from the center of gravity side of the toner to the surface side ,
Kurtosis of the distribution of the uneven distribution of B is state, and are -0.20 or +1.50 or less,
The toner is
Each particle is mixed in a dispersion obtained by mixing the first resin particle dispersion in which the first resin particles to be the binder resin are dispersed, and the colorant particle dispersion in which the particles of the colorant are dispersed. Coagulate to form first agglomerated particles,
After obtaining a first aggregated particle dispersion in which the first aggregated particles are dispersed, a mixed dispersion in which second resin particles to be the binder resin and particles of the releasing agent are dispersed is the mixed dispersion. The particles of the release agent are gradually added to the first agglomerated particle dispersion while the concentration of the particles of the release agent is gradually increased, and the particles of the second resin particles and the release agent are further agglomerated on the surface of the first agglomerated particles. In the step of forming the second aggregated particles, or in the aggregation process of forming the first aggregated particles, while gradually increasing the addition rate or while increasing the concentration of particles of the release agent, Adding a releasing agent particle dispersion liquid in which the particles are dispersed, and advancing aggregation of each particle to form a second aggregation particle;
Heating the second aggregated particle dispersion in which the second aggregated particles are dispersed, and coalescing 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:
Equation (1): Degree of uneven distribution B = 2 d / D
(In Formula (1), D represents the equivalent circle diameter (μm) of the toner in the cross-sectional observation of the toner, d represents the distance from the center of gravity of the toner in the cross-sectional observation of the toner to the center of the island including the releasing agent μm)))   An electrostatic charge image developer comprising the electrostatic charge image developing toner according to claim 1. A toner for electrostatic image development according to claim 1 is accommodated.
A toner cartridge that is attached to and removed from the image forming apparatus. And a developing unit for containing the electrostatic charge image developer according to claim 2 and developing the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer.
Process cartridge that is attached to and detached from the image forming apparatus. An image carrier,
Charging means for charging the surface of the image carrier;
Electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image carrier;
3. A developing unit for containing the electrostatic charge image developer according to claim 2, and developing the electrostatic charge image formed on the surface of the image carrier as the toner image by the electrostatic charge image developer.
A transfer unit configured to transfer a toner image formed on the surface of the image carrier to the surface of a recording medium;
Fixing means for fixing the toner image transferred to the surface of the recording medium;
An image forming apparatus comprising: 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 an electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer according to claim 2;
Transferring the toner image formed on the surface of the image carrier to the surface of the recording medium;
A fixing step of fixing the toner image transferred to the surface of the recording medium;
An image forming method comprising: