JP2009098677A - Color toner for electrostatic charge image development, image forming apparatus, and toner cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner, an image forming apparatus, and a toner cartridge capable of improving picture quality while suppressing the consumed amount of toner, preventing cleaning failure, improving a problem of fogging in long-term use and showing excellent image stability even when a high-speed printing machine is used. <P>SOLUTION: The color toner for electrostatic charge image development is characterized by satisfying all the following requirements (1) to (4). (1) The volume median diameter (Dv50) is not less than 4.0 μm and not more than 7.5 μm. (2) The average circularity is not less than 0.93. (3) The volume median diameter (Dv50) of the toner and the percentage number (Dns) of toner particles having a particle diameter of not less than 2.00 μm and not more than 3.56 μm satisfy a relationship of Dns≤0.233EXP(17.3/Dv50). (4) The coefficient of variation of the number of particles is not more than 24.0%. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electrostatic image developing color toner, an image forming apparatus, and a toner cartridge used for electrophotography, electrostatic photography and the like.

  In recent years, the use of image forming apparatuses such as electrophotographic copying machines has been expanded, and the market demand for image quality has been increasing. In particular, in office documents, in addition to the development of mapping technology and latent image forming technology for input, the types of character hieroglyphics are more abundant and finer at the time of output. Due to the spread and development, the reproducibility of a latent image with extremely high image quality that has few defects and unclearness in printed images is required. In particular, as a developer used when the electrostatic latent image on the latent image carrier constituting the image forming apparatus is a line image of 100 μm or less (approximately 300 dpi or more), a conventional toner having a large particle diameter is used as a fine line reproducibility. In general, the line image is not clear enough.

  In particular, in an image forming apparatus such as an electrophotographic printer using a digital image signal, a latent image is formed by gathering a certain number of dot units, and the solid portion, the halftone portion, and the light portion have different dot densities. It is expressed by However, if the toner is not arranged faithfully in the dot unit and the mismatch between the position of the dot unit and the position of the actually placed toner occurs, this corresponds to the ratio of the dot density of the black portion and the white portion of the digital latent image. There is a problem that the gradation of the toner image cannot be obtained. Furthermore, when the resolution is improved by reducing the dot size in order to improve the image quality, a phenomenon faithful to the latent image formed from the minute dots becomes more difficult, and the resolution is high and the gradation is poor. There is no denying the tendency for images to lack sharpness.

  In view of this, there has been proposed a device intended to improve the image quality by improving the reproducibility of minute dots by regulating the particle size distribution of the developer. Patent Document 1 proposes a toner having an average particle size of 6 to 8 μm, and attempts to form a latent image of fine dots with high reproducibility by reducing the particle size. Patent Document 2 discloses a toner base particle containing a toner base particle having a weight average particle diameter of 4 to 8 μm and further containing 17 to 60% by number of toner base particles having a particle diameter of 5 μm or less. Patent Document 3 discloses a magnetic toner containing 17 to 60% by number of magnetic toner base particles having a particle size of 5 μm or less. Patent Document 4 discloses toner base particles in which the content of toner base particles having a particle size of 2.0 to 4.0 μm is 15 to 40% by number in the toner particle size distribution. Further, Patent Document 5 describes a toner in which particles of 5 μm or less are about 15 to 65% by number. Further, Patent Documents 6 and 7 disclose similar toners. Further, Patent Document 8 contains 17 to 60% by number of toner base particles having a particle size of 5 μm or less, 1 to 30% by number of toner base particles having a particle size of 8 to 12.7 μm, and 16 μm or more. A toner having a specific particle size distribution in a toner having a volume average particle diameter of 4 to 10 μm and a toner having a specific particle size distribution is described. Further, in Patent Document 9, in the toner particles having a 50% volume particle diameter of 2 to 8 μm, the number of toner particles having a particle diameter of “0.7 × 50% number particle diameter” or less is 10 number% or less. Is described.

However, all of these toners contain a large number of particles having a particle size of 3.56 μm or less exceeding the upper limit of the right side in (4) of the present invention. The relative relationship is that the toner has a relatively large proportion of fine powder remaining in the toner having a predetermined particle size. In such a toner, since the ratio of fine powder is still large, particles that are not sufficiently charged are developed in a developing method that requires a toner having a fast charge rising, such as a non-magnetic one-component developing method that is charged instantly with friction. Occurs, the toner drops from the developing roller, the toner blows out, the printing history of the first round after the second round of the developing roller, and the afterimage (ghost) in which the image density selectively rises and falls, the drum cleaning failure, the development Problems remain such as contamination of the printed image due to poor toner layer formation on the roller.
JP-A-2-284158 JP-A-5-119530 JP-A-1-221755 JP-A-6-289648 JP 2001-134005 A Japanese Patent Laid-Open No. 11-147331 Japanese Patent Laid-Open No. 2001-175024 JP-A-2-000877 JP 2004-045948 A

  In recent years, life expectancy and high-speed printing have been demanded along with market demand for image quality. However, these required characteristics have not been sufficiently satisfied with the conventional toner. If there is a lot of fine powder like conventional toner, the fine powder will contaminate the member with continuous printing, the charge imparting ability to the toner will be reduced and the image will be distorted, and if it is introduced into a high speed printer, toner scattering will be noticeable There were also challenges.

Also, in order to provide high image printing, the toner particle size distribution needs to be sharp. This is because when the coarse particles are contained, the toner charge amount distribution becomes broad and a phenomenon called “selective development” occurs. “Selective development” is a phenomenon in which, when the toner charge amount distribution is broad, only the toner having the charge amount necessary for development at the time of copying is developed and consumed. Therefore, a good image can be obtained at the beginning of copying, but the density gradually decreases as copying continues, or the toner particle size increases and the image becomes gritty. Such a phenomenon is said to be inferior in selective developability. Further, the coarse powder having a low charge amount tends to significantly reduce the guaranteed life number. Patent Document 10 discloses a toner having a large number of coarse powders having a number variation coefficient of 24.2%. Such a toner is not suitable for stably providing a high-resolution image. Further, Patent Document 11 does not indicate that the particle size distribution is sharp.
JP 2003-255567 A WO2004-088431

Furthermore, it is necessary to pay attention to toner transfer characteristics in order to provide high-quality printing. The toner having a high transfer characteristic is a toner in which toner particles latently imaged on the photoreceptor have high transfer efficiency from the intermediate transfer drum or paper, or from the intermediate transfer drum to paper. Patent Documents 12 to 14 disclose pulverized toner that does not have a high average circularity from the viewpoint of the manufacturing process, which is insufficient to provide high-quality printing.
JP-A-7-98521 JP 2006-91175 A JP 2006-119616 A

  Further, gloss is one of the evaluation items of the printed image. The gloss reflects the glossiness of the image, and it may be preferable to have a high gloss value that requires photographic image quality. However, since the image may be glaring, it is better to avoid excessively high gloss.

  The present invention has been made in view of the above-mentioned background art, and the problem is that the white background portion of the image due to the presence of fine powder having a specific particle size or less, afterimage (ghost), blur (solid followability), excessive Improves image quality while suppressing gloss, etc., has good cleaning properties, improves toner such as stains during long-term use and provides excellent image stability even when using a high-speed printer. There is to do. Another object of the present invention is to provide a toner that suppresses gloss even though the particle size of the toner is small.

  Another object of the present invention is to provide a toner that can prevent “selective development” and stably form a high-resolution image. Furthermore, another object is to provide an image forming apparatus using the toner and a toner cartridge.

As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved when a specific relational expression is satisfied with respect to the toner particle diameter, and the present invention has been completed.
That is, the present invention resides in an electrostatic image developing color toner characterized by satisfying all of the following (1) to (4).
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.5 μm or less.
(2) The average circularity is 0.93 or more.
(3) The relationship between the volume median diameter (Dv50) of toner and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50).
(4) The number variation coefficient is 24.0% or less.

Further, the present invention provides an image forming apparatus using a color toner that satisfies all of the following (1) to (4):
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.5 μm or less.
(2) The average circularity is 0.93 or more.
(3) The relationship between the volume median diameter (Dv50) of toner and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50).
(4) The number variation coefficient is 24.0% or less.

Further, the present invention provides a toner cartridge using a color toner that satisfies all of the following (1) to (4).
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.5 μm or less.
(2) The average circularity is 0.93 or more.
(3) The relationship between the volume median diameter (Dv50) of toner and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50).
(4) The number variation coefficient is 24.0% or less.

According to the present invention, the charging is excellent and the surface potential on the developing roller is improved, and the occurrence of stains on the image white background, afterimage (ghost), blur (solid followability), excessive gloss, etc. is suppressed, and cleaning is performed. The toner can be supplied with good image stability, less likely to cause the above problems even during long-term use, and excellent in image stability. In addition, even during image formation by a high-speed printing method that has been developed in recent years, the toner particle size distribution is narrow, and even if the toner particle size is reduced, the amount of fine powder is small, so the toner powder filling rate, that is, the bulk density is improved. To do. Along with this, the air content intervening in the gap between the toner base particles is reduced, so that the heat insulation effect by the air is reduced, so that the heat conduction is improved and the fixing property by heating is improved. Guessed.
Furthermore, a toner with reduced gloss can be provided.

  Further, “selective development” can be prevented, and a high-resolution image can be stably provided even in long-term printing. In addition, it has excellent transfer characteristics, and it is possible to prevent in-machine contamination.

Hereinafter, the present invention will be described. However, the present invention is not limited to the following embodiments, and can be arbitrarily modified and implemented.
The color toner for developing an electrostatic image of the present invention (hereinafter sometimes abbreviated as “color toner” or “toner”) satisfies all of the following (1) to (4).
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.5 μm or less.
(2) The average circularity is 0.93 or more.
(3) The relationship between the volume median diameter (Dv50) of toner and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50).
(4) The number variation coefficient is 24.0% or less.

Regarding (1) The volume median diameter (Dv50) of the color toner is measured by the method described in the examples and is defined as the value measured as such. When the color toner of the present invention is one obtained by fixing or adhering an external additive to the surface of the toner base particles, it is measured as a measurement sample. Similarly, the average circularity, the number% (Dns) of toner having a particle size of 2.00 μm to 3.56 μm, and the number variation coefficient, which will be described later, are similarly fixed or adhered to the surface of the toner base particles. If it is a sample, measure it as a measurement sample.

  The Dv50 of the color toner of the present invention is 4.0 μm or more and 7.5 μm or less. Within this range, a high-quality image can be sufficiently provided. In order to give a high-quality image, the effect is more remarkable when the thickness is 6.8 μm or less. Moreover, it is preferable that it is 4.5 micrometers or more from a viewpoint of reducing the generation amount of a fine powder, It is still more preferable that it is 5.0 micrometers or more, It is especially more preferable that it is 5.3 micrometers or more.

Regarding (2) The average circularity of the color toner is measured by the method described in the examples and is defined as that measured. The average circularity of the toner of the present invention is 0.93 or more, and preferably 0.94 or more. In general, toner with a high degree of circularity has good transfer efficiency. Spherical toner having a high degree of circularity is less likely to get caught between toners or various members, so that the mechanical share of the charging roller is small, and the shape change of the surface is slight. Further, since the fluidity of the toner base itself is high, even if the amount of the externally added inorganic powder changes, the fluidity hardly changes greatly. As described above, the spherical toner has a form factor with less toner deterioration. Furthermore, since the release property from the photosensitive drum is excellent, the transfer efficiency is excellent, so that a sufficient image density can be ensured and the transfer residual toner can be reduced. For these reasons, it is desirable to use toner having a high degree of circularity as the toner used in the high-speed printer.

However, toner having a high average circularity tends to increase the weakly charged toner ratio WST [%] measured by the E-SPART analyzer, and toner scattering may be deteriorated. Further, when the transfer residual toner is scraped off by the cleaning blade, the cleaning blade can be easily passed through, which causes the image to become dirty. In the case of high-speed printing, the effect becomes more remarkable. Therefore, the average circularity of the toner of the present invention is preferably 0.98 or less, more preferably 0.96 or less.

In addition, toner with a small particle size and high circularity is difficult to scrape off with a cleaning blade, and the toner can easily pass through the cleaning blade. Therefore, the particle size distribution should be controlled according to the circularity. Is important.
About (3) The number% (Dns) of the color toner having a particle diameter of 2.00 μm or more and 3.56 μm or less is measured by the method described in Examples, and is defined as that measured. In the toner of the present invention, the relationship between the volume median diameter (Dv50) of toner and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm is Dns ≦ 0.233EXP (17.3 / Dv50). ) In the present invention, “EXP” indicates “Exponential”. That is, the base of the natural logarithm, and the right side is the exponent.

  The purpose of this relational expression is that the amount of fine powder increases as the volume median diameter (Dv) of the toner decreases, and when the Dv is 4.5 μm or less, the value of Dv becomes the particle size. In order to approach the region of 2.00 μm or more and 3.56 μm or less, the value of Dns increases exponentially. Such an area of 2.00 μm or more and 3.56 μm or less is an area expressed by a specified channel of Multisizer III manufactured by Coulter Counter.

  In the present invention, the particles included in the particle diameter range of 2.00 μm to 3.56 μm is a particle size region that should be specifically excluded in the region of the volume median diameter of toner particles of 4.0 to 7.5 μm. The basis for this follows experimental results. The color toner of the present invention satisfying the condition (3) of the particle size distribution provides high image quality, and is less contaminated even when a high-speed printing machine is used, and afterimage (ghost) and blur (solid followability). ) And is excellent in cleaning properties. In addition, since the charge amount distribution is very sharp because the particle size distribution is sharp, particles with a small charge amount do not cause the white background portion of the image to be smeared or scattered to stain the inside of the apparatus, Particles having a large charge amount do not develop and do not adhere to members such as a layer regulating blade or a roller and cause image defects such as streaks and blurring.

That is, the amount of fine powder affects the image with the above relational expression as a boundary. When the value of Dns exceeds the right side, the fine powder causes a defect in the image.
Since the image forming apparatus is designed to transfer particles having a specific charge amount, first, the particles having the specific charge amount are preferentially transferred to the OPC during electrostatic development. The particles exceeding the specific charge amount adhere to a member or the like and are contaminated or fluidity is deteriorated. On the other hand, particles that do not satisfy a specific charge amount accumulate in the cartridge and contaminate members and the like.

  Here, the toner charge amount correlates with the particle size of the toner when the toner composition is the same. Generally, the smaller the particle size, the higher the charge amount per unit weight, and the larger the charge amount, the smaller the charge amount per unit weight. Become. That is, if there is a large amount of toner having a small particle size, the charge amount becomes too high, and this causes adhesion to a member or the like and deterioration of toner fluidity. In the present invention, this toner is specified to be 3.56 μm or less. This 3.56 μm is a value defined for the channel of the measuring apparatus. On the other hand, the lower limit value was set to 2.00 μm because of the measurement limit of the measuring apparatus.

Further, the relationship between Dv50 and Dns is Dns ≦ 0.110EXP (19.9 / Dv50).
A toner satisfying the above condition is preferable. On the other hand, from the viewpoint of producing with good yield, Dv5
It is preferable that the relationship between 0 and Dns satisfies 0.0517EXP (22.4 / Dv50) ≦ Dns.
In addition, a toner having a Dns of 6% by number or less is preferable in terms of providing a higher quality image and hardly contaminating the image forming apparatus. Further, it is more preferable that the above-described preferable particle diameter range of Dv50, for example, “Dv50 is 4.5 μm or more” and “Dns is 6% by number or less” are combined and satisfied. Within this range, it is possible to provide a high-quality image or a toner that hardly contaminates the image forming apparatus without reducing the yield from the viewpoint of production.
Regarding (4): The number variation coefficient (%) is measured by the method described in the examples and is defined as that measured.

  The number variation coefficient of the color toner of the present invention is 24.0% or less, preferably 22%, more preferably 20% or less, and still more preferably 19% or less. When the value of the number variation coefficient is high, the distribution of the charge amount becomes broad, and an image defect is caused from a charging failure. Furthermore, contamination due to adhesion to the toner member or the like and contamination due to scattering are induced. Therefore, it is preferable that the number variation coefficient is low. On the other hand, from an industrial standpoint, the number variation coefficient is preferably 0% or more, and more preferably 5% or more.

  The color toner of the present invention must satisfy all the above (1) to (4). Conventional toners do not satisfy any of (1) to (4). As a reason for this, if it is attempted to reduce the fine powder as much as possible (satisfies (3)), coarse powder is generated and the number variation coefficient increases (not satisfy (4)). In addition, trying to round the toner by physical impact (satisfies (2)) causes the generation of fine powder (does not satisfy (3)), or rounds the toner by thermal fusion. If (2) is satisfied, the particles are fused with each other and coarse powder is generated (not satisfying (4)).

  The color toner of the present invention can provide high image quality, has little contamination even when a high-speed printing machine is used, suppresses afterimage (ghost) and blurring (solid followability), and has excellent cleaning properties. In addition, since the charge amount distribution is very sharp because the particle size distribution is sharp, particles with a small charge amount do not cause the white background portion of the image to be smeared or scattered to stain the inside of the apparatus, Particles having a large charge amount do not develop and do not adhere to members such as a layer regulating blade or a roller and cause image defects such as streaks and blurring. Furthermore, when there are many fine powders ((3) is not satisfy | filled), it exists in the tendency for gross to become high. Further, the gloss increases as the toner particle size decreases. Therefore, when the particle size of the toner is small, the gloss tends to be too high due to the presence of the fine powder. However, the gloss can be suppressed by reducing the fine powder (satisfy (3)).

  The color toner of the present invention has a very sharp charge amount distribution as compared with conventional toners. The charge amount distribution has a correlation with the particle size distribution of the toner. When the toner has a broad particle size distribution like a conventional toner, the charge amount distribution is also broad. When the charge amount distribution becomes broad, the ratio of particles with low charge or particles with high charge that cannot be controlled by the developing conditions of the toner device increases, causing various image defects. For example, particles with a small charge amount cause stains on the white background of the image or scatter in the apparatus, and particles with a large charge amount are not developed and are layer regulating blades in the developing tank. And accumulated in members such as rollers and cause image defects such as streaks and fading due to fusion.

  In the present invention, the surface potential of the toner is preferably −30 V or less, more preferably −32 V or less, and even more preferably −34 or less. This surface potential is measured by the method described later, and means the toner surface potential on the developing roller. If it is within the above range, since the rising of the charge is good, white background fog and afterimage (ghost) can be suppressed, and a higher resolution image can be provided.

  Further, the gloss value depends on the smoothness of the surface of the toner print image, and generally the smoother surface suppresses light scattering, so the gloss value becomes higher. When the particle size distribution of the toner is broad, it is considered that the fineness of the fine particles increases and the small particle size particles are buried in the voids between the large particles, thereby improving the smoothness of the surface and increasing the gloss. Therefore, if the particle size distribution is sharp, the smoothness is considered to be slightly reduced, which is advantageous for suppressing an excessive gloss value. In the present invention, the gloss value of the solid print image is preferably 32 or less, and more preferably 30 or less.

  In the development process design in the image forming apparatus, the development process conditions are set so as to conform to the average value of the toner charge amount. The apparatus causes image defects such as scattering, streaks, and fading, and the matching with the apparatus is not good. On the other hand, if the charge amount distribution is sharp as in the present invention, the developability can be controlled by bias adjustment or the like, and a clear image can be given without contaminating the members of the image forming apparatus. is there.

Since the toner of the present invention has a sharp charge amount distribution, the contamination (toner scattering) in the image forming apparatus caused by poorly charged toner is very small. This effect is remarkably exhibited particularly in a high-speed type image forming apparatus in which the development process speed for the electrostatic latent image carrier is 100 mm / second or more.
In addition, the color toner of the present invention has a sharp charge amount distribution, so that the developability is very good, and there are very few toner particles that accumulate without being developed. The effect is exhibited in the forming apparatus. Specifically, a toner used for an image forming apparatus that satisfies the following formula (5) is preferable in order to sufficiently exhibit the above-described effects of the present invention.
(5) Guaranteed lifetime number of sheets (sheets) x printing rate ≧ 400 (sheets) of the developer filled with developer
In the formula (5), “printing rate” is represented by a value obtained by dividing the sum of the printed portion areas by the total area of the printing medium in the printed matter for determining the guaranteed life number as the performance of the image forming apparatus. The “print rate” of the print% of “5%” is “0.05”.

Furthermore, since the color toner of the present invention has a very sharp particle size distribution, the latent image reproducibility is very good. Therefore, the effect of the present invention is sufficiently exerted particularly when used in an image forming apparatus having a resolution of 600 dpi or more for the electrostatic latent image carrier.
The image forming apparatus and the toner cartridge of the present invention are characterized by using a toner that satisfies all of the above (1) to (4). By using such a toner, a high-resolution image can be provided.
<Configuration of toner>
The color toner of the present invention is constituted by appropriately selecting a binder resin, a colorant, a wax, an external additive and the like.

  The binder resin constituting the color toner of the present invention may be appropriately selected from those known to be usable for toner. For example, styrene resin, vinyl chloride resin, rosin modified maleic acid resin, phenol resin, epoxy resin, saturated or unsaturated polyester resin, polyethylene resin, polypropylene resin, ionomer resin, polyurethane resin, silicone resin, ketone resin, Ethylene-acrylate copolymer, xylene resin, polyvinyl butyral resin, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-anhydrous malein An acid copolymer etc. can be mentioned. These resins can be used alone or in combination.

The colorant constituting the color toner of the present invention may be appropriately selected from those known to be usable for toner. Examples thereof include yellow pigments, magenta pigments, and cyan pigments shown below.
Of these, compounds represented by condensed azo compounds, isoindolinone compounds and the like are used as yellow pigments. Specifically, C.I. I. CI Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 109, 110, 111, 128, 129, 147, 150, 155, 168, 180, 194, etc. are preferably used. It is done.

  As the magenta pigment, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds are used. Specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 166, 169, 17.3, 184, 185, 202, 206, 207, 209, 220, 221, 238, 254, 269, C.I. I. Pigment Violet 19 or the like is preferably used. Among them, C.I. I. Pigment red 122, 202, 207, 209, C.I. I. A quinacridone pigment represented by pigment violet 19 is particularly preferred. Among the quinacridone pigments, C.I. I. A compound represented by CI Pigment Red 122 is particularly preferable.

As the cyan pigment, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds, and the like can be used. Specifically, C.I. I. Pigment blue 1, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66 and the like; I. Pigment Green 7, 36, etc. can be used particularly preferably.
It is preferable to add a wax to the color toner of the present invention to impart releasability. Any wax can be used as long as it has releasability, and is not particularly limited. Specifically, olefin waxes such as low molecular weight polyethylene, low molecular weight polypropylene, and copolymer polyethylene; paraffin wax; ester waxes having a long-chain aliphatic group such as behenyl behenate, montanate ester, stearyl stearate; water Plant waxes such as added castor oil and carnauba wax; ketones having a long chain alkyl group such as distearyl ketone; silicones having an alkyl group; higher fatty acids such as stearic acid; long chain aliphatic alcohols such as eicosanol; glycerin and pentaerythritol Examples include carboxylic acid esters or partial esters of polyhydric alcohols obtained from polyhydric alcohols such as polyhydric alcohols and long chain fatty acids; higher fatty acid amides such as oleic acid amides and stearic acid amides; low molecular weight polyesters and the like.

  In order to improve the fixability among these waxes, the melting point of the wax is preferably 30 ° C. or higher, more preferably 40 ° C. or higher, and particularly preferably 50 ° C. or higher. Moreover, 100 degrees C or less is preferable, 90 degrees C or less is still more preferable, and 80 degrees C or less is especially preferable. If the melting point is too low, the wax tends to be exposed and sticky after fixing, and if the melting point is too high, the fixability at low temperatures is poor. Furthermore, as the wax compound species, ester waxes obtained from aliphatic carboxylic acids and mono- or polyhydric alcohols are preferred, and ester waxes having 20 to 100 carbon atoms are preferred.

The above waxes may be used alone or in combination. Further, the melting point of the wax compound can be appropriately selected depending on the fixing temperature for fixing the toner. The amount of the wax used is preferably 4 to 20 parts by weight, particularly preferably 6 to 18 parts by weight, and more preferably 8 to 15 parts by weight with respect to 100 parts by weight of the toner. In addition, when the volume median diameter (Dv50) of the toner is 7 μm or less, that is, when the toner has a small particle diameter, the exposure of the wax to the toner surface becomes extremely intense as the amount of the wax used increases. The storage stability of the toner is deteriorated. The toner of the present invention has a small particle size with a sharp particle size distribution that does not cause deterioration of the toner characteristics as compared with conventional toners even when the amount of wax used is large as in the above range. It is.

The color toner of the present invention may be one in which a known external additive is blended on the surface of the toner base particles in order to control fluidity and developability. External additives include metal oxides and hydroxides such as alumina, silica, titania, zinc oxide, zirconium oxide, cerium oxide, talc and hydrotalcite, titanium such as calcium titanate, strontium titanate and barium titanate. Examples thereof include acid metal salts, nitrides such as titanium nitride and silicon nitride, carbides such as titanium carbide and silicon carbide, and organic particles such as acrylic resins and melamine resins, and a plurality of them can be combined. Among these, silica, titania, and alumina are preferable, and those that have been surface-treated with, for example, a silane coupling agent or silicone oil are more preferable. The average primary particle diameter is preferably in the range of 1 to 500 nm, more preferably in the range of 5 to 100 nm. It is also preferable to use a combination of a small particle size and a large particle size in the particle size range. The total amount of the external additive is preferably in the range of 0.05 to 10 parts by weight, more preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the toner base particles.
<Toner production method>
The method for producing the color toner of the present invention is not particularly limited. That is, the toner can be produced by a pulverization method or a polymerization method. When a toner is manufactured by a pulverization method, fine particles are generally easily generated, so that a classification step is necessary. However, since the yield is remarkably lowered by an excessive classification operation, such an operation is not performed from an industrial viewpoint. On the other hand, the toner of the present invention preferably forms particles in an aqueous medium from the viewpoint of hardly generating fine powder.

The following describes a method for producing particles by polymerizing in an aqueous medium from the viewpoint of hardly generating fine powder among methods for forming particles in an aqueous medium, and further a method for producing particles by an emulsion polymerization aggregation method. To do.
In order to obtain a toner satisfying the above formula (3), it is preferable to employ an operation in which the aggregation speed is not high compared to the operation normally performed in the aggregation step. Examples of operations that do not cause the aggregation speed to be high include, for example, cooling the dispersion to be used in advance, adding the dispersion over time, adopting an electrolyte that does not have a large aggregating action, continuously using the electrolyte, or There are methods such as intermittent addition, slowing the rate of temperature rise, and long aggregation time. In the aging step, it is preferable to adopt an operation in which the aggregated particles are difficult to redisperse. Examples of the operation in which the agglomerated particles are difficult to finely disperse include, for example, a method in which the number of revolutions for stirring is decreased, a dispersion stabilizer is added continuously or intermittently, and a dispersion stabilizer and water are mixed in advance. Further, the toner satisfying the above formula (3) does not go through a step of removing particles having a volume median diameter (Dv50) or less from the finally obtained toner or toner base particles by an operation such as classification. It is preferable to be obtained.

  As a production method for obtaining a toner in an aqueous medium, a method in which radical polymerization is carried out in an aqueous medium such as a suspension polymerization method or an emulsion polymerization aggregation method (hereinafter abbreviated as “polymerization method”), the obtained toner is “polymerized”. (Abbreviated as “toner”), a chemical pulverization method typified by a melt suspension method, and the like can be preferably used. There is no particular limitation on the method for making the toner have a particle size in the specific range of the present invention. For example, in the production process of the polymerized toner, in the case of the suspension polymerization method, a method in which a high shearing force is applied in the process in which polymerizable monomer droplets are generated, or a dispersion stabilizer or the like is increased.

As a method for obtaining a color toner having a particle size in the specific range of the present invention, any of polymerization methods such as the above-described suspension polymerization method, emulsion polymerization aggregation method, chemical pulverization method represented by the melt suspension method, etc. The production method can also be used, but in both the “suspension polymerization method” and the “chemical pulverization method represented by the melt suspension method”, both are adjusted from a size larger than the particle size of the toner to a smaller size. Therefore, when trying to reduce the average particle size, the particle size ratio on the small particle side tends to increase,
An excessive burden is imposed on the classification process. In contrast, the emulsion polymerization agglomeration method has a relatively sharp particle size distribution and is adjusted from a size smaller than the particle size of the toner to a larger size. A toner having a distribution is obtained. Therefore, it is particularly preferable to produce the color toner of the present invention by the emulsion polymerization aggregation method for the above reasons.

  Hereinafter, the toner produced by the emulsion polymerization aggregation method will be described in more detail. When a toner is produced by an emulsion polymerization aggregation method, it usually has a polymerization process, a mixing process, an aggregation process, an aging process, and a washing / drying process. That is, generally, a dispersion liquid containing primary polymer particles obtained by emulsion polymerization is mixed with a dispersion liquid such as a colorant, a charge control agent, and wax, and the primary particles in the dispersion liquid are aggregated to form core particles. Then, if necessary, the toner base particles can be obtained by washing and drying the particles obtained by fusing and adhering the resin fine particles or the like as necessary.

  As the binder resin constituting the polymer primary particles used in the emulsion polymerization aggregation method, one or more polymerizable monomers that can be polymerized by the emulsion polymerization method may be appropriately used. Examples of the polymerizable monomer include “a polymerizable monomer having an acidic group” (hereinafter sometimes simply referred to as “acidic monomer”), “a polymerizable monomer having a basic group” (hereinafter simply referred to as “basic monomer”). "Polymerizable monomer having a polar group" (hereinafter sometimes referred to simply as "polar monomer") and "polymerizability having neither an acidic group nor a basic group" It is preferable to use “monomer” (hereinafter sometimes referred to as “other monomer”) as a raw material polymerizable monomer. At this time, each polymerizable monomer may be added separately, or a plurality of polymerizable monomers may be mixed in advance and added simultaneously. Furthermore, it is also possible to change the polymerizable monomer composition during the addition of the polymerizable monomer. Further, the polymerizable monomer may be added as it is, or may be added as an emulsion prepared by mixing with water or an emulsifier in advance.

  Examples of the “acidic monomer” include polymerizable monomers having a carboxyl group such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and cinnamic acid, polymerizable monomers having a sulfonic acid group such as sulfonated styrene, vinyl Examples thereof include polymerizable monomers having a sulfonamide group such as benzenesulfonamide. Examples of the “basic monomer” include aromatic vinyl compounds having an amino group such as aminostyrene, and nitrogen-containing heterocyclic ring-containing polymerizable monomers such as vinylpyridine and vinylpyrrolidone.

  These polar monomers may be used alone or in combination, and may exist as a salt with a counter ion. Among these, it is preferable to use an acidic monomer, and (meth) acrylic acid is more preferable. The proportion of the total amount of polar monomers in 100% by mass of all polymerizable monomers constituting the binder resin as the polymer primary particles is preferably 0.05% by mass or more, more preferably 0.3% by mass or more, and particularly Preferably it is 0.5 mass% or more, More preferably, it is 1 mass% or more. The upper limit is preferably 10% by mass or less, more preferably 5% by mass or less, and particularly preferably 2% by mass or less. When it is in the above range, the dispersion stability of the obtained polymer primary particles is improved, and the particle shape and particle diameter can be easily adjusted in the aggregation step.

“Other monomers” include styrenes such as styrene, methylstyrene, chlorostyrene, dichlorostyrene, p-tert-butylstyrene, pn-butylstyrene, pn-nonylstyrene, methyl acrylate, acrylic acid Acrylic esters such as ethyl, propyl acrylate, n-butyl acrylate, isobutyl acrylate, hydroxyethyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, methacryl Methacrylates such as isobutyl acid, hydroxyethyl methacrylate, ethylhexyl methacrylate, acrylamide, N-propylacrylamide, N, N-dimethylacrylamide, N, N-
Dipropylacrylamide, N, N-dibutylacrylamide, acrylic acid amide and the like can be mentioned. A polymerizable monomer may be used independently and may be used in combination of multiple.

  In the present invention, among the above-mentioned polymerizable monomers used in combination, as a preferred embodiment, an acidic monomer and other monomers may be used in combination. More preferably, (meth) acrylic acid is used as the acidic monomer, and a polymerizable monomer selected from styrenes and (meth) acrylic acid esters is used as the other monomer. It is preferable to use (meth) acrylic acid as the monomer, and to use a combination of styrene and (meth) acrylic acid esters as the other monomer, particularly preferably (meth) acrylic acid as the acidic monomer and other monomers. As a combination of styrene and n-butyl acrylate.

  Furthermore, it is also preferable to use a crosslinked resin as the binder resin constituting the polymer primary particles. In that case, a polyfunctional monomer having radical polymerizability is used as a crosslinking agent shared with the above polymerizable monomer. Examples of the multifunctional monomer include divinylbenzene, hexanediol diacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, neopentyl glycol dimethacrylate, neopentyl glycol acrylate, diallyl phthalate, and the like. Is mentioned. In addition, a polymerizable monomer having a reactive group in a pendant group such as glycidyl methacrylate, methylol acrylamide, acrolein or the like can be used as a crosslinking agent. Among them, radically polymerizable bifunctional monomers are preferable, and divinylbenzene and hexanediol diacrylate are particularly preferable.

  These crosslinking agents such as polyfunctional monomers may be used alone or in combination. When a crosslinked resin is used as the binder resin constituting the polymer primary particles, the blending ratio of the crosslinking agent such as a polyfunctional monomer in the total polymerizable monomer constituting the resin is preferably 0.005% by mass or more, More preferably, it is 0.1 mass% or more, More preferably, it is 0.3 mass% or more, Preferably it is 5 mass% or less, More preferably, it is 3 mass% or less, More preferably, it is 1 mass% or less. desirable.

Known emulsifiers can be used for emulsion polymerization, but one or more emulsifiers selected from cationic surfactants, anionic surfactants and nonionic surfactants are used in combination. be able to.
Examples of the cationic surfactant include dodecyl ammonium chloride, dodecyl ammonium bromide, dodecyl trimethyl ammonium bromide, dodecyl pyridinium chloride, dodecyl pyridinium bromide, hexadecyl trimethyl ammonium bromide and the like.

Examples of the anionic surfactant include fatty acid soaps such as sodium stearate and sodium dodecanoate, sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and sodium lauryl sulfate.
Nonionic surfactants include, for example, polyoxyethylene dodecyl ether, polyoxyethylene hexadecyl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl ether, polyoxyethylene sorbitan monooleate ether, monodecanoyl sucrose, etc. Is mentioned.

The amount of the emulsifier is usually 1 to 10 parts by weight with respect to 100 parts by weight of the polymerizable monomer, and these emulsifiers include, for example, partially or completely saponified polyvinyl alcohol such as saponified polyvinyl alcohol, hydroxy One type or two or more types of cellulose derivatives such as ethyl cellulose can be used in combination as a protective colloid.
Examples of the polymerization initiator include hydrogen peroxide; persulfates such as potassium persulfate; organic peroxides such as benzoyl peroxide and lauroyl peroxide; 2,2′-azobisisobutyronitrile; Azo compounds such as 2′-azobis (2,4-dimethylvaleronitrile); redox initiators and the like are used. One or more of them are usually used in an amount of about 0.1 to 3 parts by weight per 100 parts by weight of the polymerizable monomer. Among them, it is preferable that at least a part or all of the initiator is hydrogen peroxide or organic peroxides.

Any of the polymerization initiators may be added to the polymerization system before, simultaneously with, or after the addition of the polymerizable monomer, and these addition methods may be combined as necessary.
In the emulsion polymerization, a known chain transfer agent may be used as necessary. Specific examples of such a chain transfer agent include t-dodecyl mercaptan, 2-mercaptoethanol, diisopropyl xanthogen, four Examples thereof include carbon chloride and trichlorobromomethane. The chain transfer agent may be used alone or in combination of two or more, and is usually used in a range of 5% by mass or less based on the total polymerizable monomer. Moreover, a pH adjuster, a polymerization degree adjuster, an antifoaming agent, etc. can be further mix | blended with a reaction system suitably.

In the emulsion polymerization, the polymerizable monomer is polymerized in the presence of a polymerization initiator, and the polymerization temperature is usually 50 to 120 ° C, preferably 60 to 100 ° C, more preferably 70 to 90 ° C.
The volume average diameter (Mv) of the polymer primary particles obtained by emulsion polymerization is usually 0.02 μm or more, preferably 0.05 μm or more, more preferably 0.1 μm or more, and usually 3 μm or less, preferably 2 μm or less. More preferably, the thickness is 1 μm or less. When the particle size is less than the above range, it may be difficult to control the aggregation rate. When the particle size exceeds the above range, the particle size of the toner obtained by aggregation tends to be large, and a toner having the target particle size can be obtained. It can be difficult.

  Tg by the DSC method of the binder resin as the polymer primary particles in the present invention is preferably 40 to 80 ° C, more preferably 55 to 65 ° C. Within this range, the storage stability is good and, in addition, the cohesiveness is not impaired. When Tg is too high, the cohesiveness is poor, and an aggregating agent must be added excessively or the aggregation temperature must be excessively increased. As a result, fine powder may be easily generated. Here, when the Tg of the binder resin overlaps with the caloric change based on other components, for example, the melting peak of polylactone or wax, it is not possible to make a clear judgment, and the toner was prepared in a state in which such other components were excluded. The Tg at the time is meant.

In the present invention, the acid value of the binder resin constituting the polymer primary particles is preferably 3 to 50 mgKOH / g, more preferably 5 to 30 mgKOH / g, as a value measured by the method of JISK-0070. .
The lower limit of the solid content concentration of the polymer primary particles in the “polymer primary particle dispersion” used in the present invention is preferably 14% by mass or more, and more preferably 21% by mass or more. On the other hand, the upper limit is preferably 30% by mass or less, and more preferably 25% by mass or less. When it is within the above range, it is easy to adjust the aggregation speed of the polymer primary particles empirically in the aggregation process, and as a result, it is easy to adjust the particle size, particle shape, and particle size distribution of the core particles to any range It becomes.

In the present invention, a dispersion liquid containing polymer primary particles obtained by emulsion polymerization is mixed with a dispersion liquid such as a colorant, a charge control agent, and wax, and the primary particles in the dispersion liquid are aggregated to form core particles. The toner base particles are preferably obtained by washing and drying the particles obtained by fixing or adhering resin fine particles or the like and then fusing them.
The resin fine particles may be produced by the same method as the above polymer primary particles, and the structure thereof is not particularly limited, but the polar monomer occupying in 100% by mass of all polymerizable monomers constituting the binder resin as the resin fine particles The ratio of the total amount is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, and further preferably 0.2% by mass or more. The upper limit is preferably 3% by mass or less, more preferably 1.5% by mass or less. When it is in the above range, the dispersion stability of the obtained resin fine particles is improved, and it becomes easy to adjust the particle shape and particle diameter in the aggregation process.

  Further, the proportion of the total amount of polar monomers in 100% by mass of the total polymerizable monomer constituting the binder resin as the resin fine particles is in 100% by mass of the total polymerizable monomer constituting the binder resin as the polymer primary particle. It is preferable that the ratio is smaller than the ratio of the total amount of polar monomers in view of easy adjustment of the particle shape and particle diameter in the aggregation process, generation of fine powder can be suppressed, and excellent charging characteristics.

In addition, the Tg of the binder resin as the resin fine particles is preferably higher than the Tg of the binder resin as the polymer primary particles from the viewpoint of storage stability and the like.
The colorant is not particularly limited as long as it is a commonly used colorant. For example, the pigment mentioned above is mentioned. The content of the colorant may be an amount sufficient for the obtained toner to form a visible image by development. For example, the content is preferably in the range of 1 to 25 parts by weight, more preferably 1 to 15 parts by weight, particularly preferably 3 to 12 parts by weight.

  As a blending method of the colorant in the emulsion polymerization aggregation method, usually, a polymer primary particle dispersion and a colorant dispersion are mixed to form a mixed dispersion, and then aggregated to obtain a particle aggregate. The colorant is preferably used in the state of being emulsified in water by a mechanical means such as a sand mill or a bead mill in the presence of an emulsifier. At this time, the colorant dispersion is preferably added with 10 to 30 parts by weight of the colorant and 1 to 15 parts by weight of the emulsifier with respect to 100 parts by weight of water. The particle diameter of the colorant in the dispersion is monitored while being dispersed, and the volume average diameter (Mv) is finally adjusted to 0.01 to 3 μm, more preferably 0.05 to It is preferable to control within the range of 0.5 μm. The blend of the colorant dispersion at the time of emulsion aggregation is calculated and used so as to be 2 to 10% by mass in the finished toner base particles after aggregation.

The wax may be contained in the polymer primary particles or in the resin fine particles. However, in general, as the amount of wax used increases, aggregation control tends to deteriorate and the particle size distribution tends to become broader.
Therefore, as a method of blending the wax in the emulsion polymerization aggregation method, a wax dispersion that has been previously emulsified and dispersed in water at a volume average diameter (Mv) of 0.01 to 2.0 μm, more preferably 0.01 to 0.5 μm is emulsified. It is preferable to add at the time of superposition | polymerization or to add at the aggregation process. In order to disperse the wax with a suitable dispersed particle diameter in the toner, it is preferable to add the wax as a seed during emulsion polymerization. By adding as a seed, polymer primary particles in which wax is encapsulated can be obtained, so that a large amount of wax does not exist on the toner surface, and deterioration of chargeability and heat resistance of the toner can be suppressed. The wax content in the polymer primary particles is preferably 4 to 30% by mass, more preferably 5 to 20% by mass, and particularly preferably 7 to 15% by mass.

Also, wax may be contained in the resin fine particles, and in this case as well, it is preferable to add wax as a seed during emulsion polymerization, as in the case of obtaining polymer primary particles. The content ratio of the wax in the entire resin fine particles is preferably smaller than the content ratio of the wax in the entire polymer primary particles. Generally, when wax is contained in resin fine particles, the fixability is improved, but on the other hand, the generation amount of fine powder tends to increase. The reason for this is that the fixability is improved because the speed of movement of the wax to the toner surface is increased when subjected to heat, but the inclusion of the wax in the resin fine particles broadens the particle size distribution of the resin fine particles. It is considered that the aggregation control becomes difficult, and as a result, an increase in fine powder is caused.

  The color toner of the present invention may be blended with a charge control agent in order to impart charge amount and charge stability. Conventionally known compounds are used as the charge control agent. Examples thereof include hydroxycarboxylic acid metal complexes, azo compound metal complexes, naphthol compounds, naphthol compound metal compounds, nigrosine dyes, quaternary ammonium salts, and mixtures thereof. The blending amount of the charge control agent is preferably in the range of 0.1 to 5 parts by weight with respect to 100 parts by weight of the resin.

When a charge control agent is contained in the toner in the emulsion polymerization aggregation method, the charge control agent is blended with a polymerizable monomer or the like at the time of emulsion polymerization, or is blended in the aggregation process with the polymer primary particles and the colorant. The blended primary particles, the colorant, and the like can be blended by a method such as blending after agglomeration to obtain an appropriate particle size as a toner. Among these, the charge control agent is emulsified and dispersed in water using an emulsifier, and the volume average diameter (Mv) is 0.01 μm to 3 μm.
It is preferable to use it as an emulsified dispersion of μm. The blend of the charge control agent dispersion at the time of emulsion aggregation is calculated and used so as to be 0.1 to 5% by mass in the finished toner base particles after aggregation.

The volume average diameter (Mv) of polymer primary particles, resin fine particles, colorant particles, wax particles, charge control agent particles, etc. in the above dispersion is measured using a nanotrack by the method described in the examples. , Defined as its measured value.
In the aggregation step in the emulsion polymerization aggregation method, the above-described primary polymer particles, resin fine particles, colorant particles, and charge components such as a charge control agent and wax are mixed at the same time or sequentially. It is possible to prepare a dispersion of the above components, that is, a polymer primary particle dispersion, a resin fine particle dispersion, a colorant particle dispersion, a charge control agent dispersion, and a wax fine particle dispersion. It is preferable from the viewpoint of uniformity.

  In addition, when mixing these different types of dispersions, the aggregation speed of the components contained in each dispersion is different. Are preferably mixed. Since the suitable time required for the addition varies depending on the amount of the dispersion to be mixed, the solid concentration, and the like, it is preferable to adjust appropriately. For example, when the colorant particle dispersion is mixed with the polymer primary particle dispersion, it is preferably added over 3 minutes. Also, when mixing the resin fine particle dispersion with the core particles, it is preferably added over 3 minutes.

  The agglomeration treatment includes a heating method, a method of adding an electrolyte, a method of reducing the concentration of an emulsifier in the system, a method of combining these, and the like. When primary particles are agglomerated under stirring to obtain particle agglomerates that are approximately the size of the toner, the particle size of the particle agglomerates is controlled from the balance between the agglomeration force between the particles and the shearing force due to agitation. However, the cohesive force can be increased by the above method.

As an electrolyte in the case of performing aggregation by adding an electrolyte, either an organic salt or an inorganic salt may be used. Specifically, NaCl, KCl, LiCl, Na ₂ SO ₄ , K ₂ SO ₄ , Li ₂ SO ₄ may be used. Inorganic salts having a monovalent metal cation such as CH ₃ COONa, C ₆ H ₅ SO ₃ Na; inorganic salts having a divalent metal cation such as MgCl ₂ , CaCl ₂ , MgSO ₄ , CaSO ₄ , ZnSO ₄ ; Examples thereof include inorganic salts having a trivalent metal cation such as Al ₂ (SO ₄ ) ₃ and Fe ₂ (SO ₄ ) ₃ . Among these, when an inorganic salt having a divalent or higher polyvalent metal cation is used, it is preferable in terms of productivity because the agglomeration speed is increased. On the other hand, the amount of polymer primary particles and the like that are not incorporated into the core particle is small. As a result, fine powder that does not reach the desired toner particle size is likely to be generated. Therefore, it is preferable to use an inorganic salt having a monovalent metal cation that does not have a strong aggregating action in terms of suppressing the amount of fine powder generated.

  The amount of the electrolyte used varies depending on the type of electrolyte, target particle size, etc., but is usually 0.05 to 25 parts by weight, preferably 0.1 to 15 parts per 100 parts by weight of the solid component of the mixed dispersion. Part by weight, more preferably 0.1 to 10 parts by weight. When the amount used is less than the above range, the progress of the agglutination reaction is slow, and fine particles of 1 μm or less remain after the agglomeration reaction, or the average particle size of the obtained particle aggregate does not reach the target particle size. In the case of exceeding the above range, it tends to cause rapid agglomeration, making it difficult to control the particle diameter, and may cause problems such as inclusion of coarse powder or amorphous particles in the obtained core particles. is there.

  In addition, it is preferable that the electrolyte is added not intermittently but intermittently or continuously over a certain period of time. The addition time varies depending on the amount used, but is preferably added over 0.5 minutes. Usually, when an electrolyte is added, abrupt aggregation starts as soon as the electrolyte is added, so that there is a tendency that a large amount of polymer primary particles, colorant particles, aggregates, and the like left behind in the aggregation remain. These are considered to be one of the sources of fine powder. According to the above operation, uniform agglomeration can be performed without abrupt agglomeration, so that generation of fine powder can be prevented.

  Moreover, 20-70 degreeC is preferable and, as for the final temperature of the aggregation process in the case of performing aggregation by adding electrolyte, 30-60 degreeC is more preferable. Here, controlling the temperature before the aggregation step is one of the methods for controlling the particle size within a specific range of the present invention. Some colorants added to the aggregating step induce aggregation, such as the above-described electrolyte, and sometimes agglomerate without adding an electrolyte. Therefore, the aggregation can be prevented by cooling the temperature of the polymer primary particle dispersion in advance when mixing the colorant dispersion. This aggregation causes fine powder to be generated. In the present invention, the polymer primary particles are preferably cooled in advance in a range of preferably 0 to 15 ° C, more preferably 0 to 12 ° C, and still more preferably 2 to 10 ° C. Note that this method is not effective only when the electrolyte is added to perform aggregation, and the aggregation is performed without adding an electrolyte, such as a method of controlling the pH or adding a polar organic solvent such as alcohol to perform the aggregation method. The method is also used, and is not particularly limited to the aggregation method.

The final temperature of the agglomeration step in the case of agglomeration by heating is usually in the temperature range of (Tg-20 ° C) to Tg of the polymer primary particles, and in the range of (Tg-10 ° C) to (Tg-5 ° C). It is preferable that
Further, as a method for preventing sudden aggregation in order to prevent the generation of fine powder, there is a method of adding demineralized water or the like. The method of adding demineralized water or the like is not a method that is actively employed in terms of production efficiency because the coagulation action is not so strong compared to the method of adding electrolyte, but rather, a large amount of filtrate is used in the subsequent filtration step, etc. Since it will be obtained, it may be unpreferable. However, it is very effective when fine aggregation control is required as in the present invention. Moreover, in this invention, it is preferable to employ | adopt in combination with the method of adding the said heating method, the method of adding electrolyte, etc. At this time, the method of adding demineralized water after adding the electrolyte is particularly preferable in that the aggregation is easily controlled.

  The time required for agglomeration is optimized by the shape of the apparatus and the processing scale. In order to reach the target particle size of the toner base particles, the temperature at which the aggregation process is completed, for example, the emulsifier It is preferable that the time from the temperature 8 ° C. lower than the temperature at the time of operation to stop the growth of the core particles by addition, pH control, etc. (hereinafter referred to as the aggregation final temperature) to 30 minutes or more is 1 hour. More preferably, the above is used. The polymer core particles, colorant particles, or aggregates thereof remaining by extending the time are not left behind, but are taken into the target core particles or agglomerate with each other, so that the target core is obtained. Become particles.

  In the present invention, toner mother particles can be formed by coating (adhering or fixing) resin fine particles on the surface of the core particles as necessary. The volume average diameter (Mv) of the resin fine particles is preferably 0.02 μm to 3 μm, more preferably 0.05 μm to 1.5 μm. In general, the use of the resin fine particles promotes the generation of fine powder that does not reach a predetermined toner particle size. Therefore, the toner coated with the conventional resin fine particles increases in the amount of fine powder that does not satisfy the predetermined toner particle size.

In the present invention, when the amount of the wax is increased, the high temperature fixability is improved, but the wax tends to be exposed on the toner surface, so that the chargeability and heat resistance may be deteriorated. The deterioration of performance can be prevented by coating with resin fine particles not containing.
However, when the resin fine particles contain wax for the purpose of improving the high-temperature fixability, the resin fine particles once attached to the surface of the core particles are easily peeled off. This is because the particle size distribution of the resin fine particles described above becomes wide, and there are large particle size resin fine particles with weak adhesion. Therefore, in order to reduce the peeling off, it is preferable to raise the temperature while adding an aqueous solution in which a dispersion stabilizer and water are mixed in advance in a liquid in which particles having resin fine particles attached to the surface are dispersed. .

  When adopting the conventional method “step of starting the temperature rise after the addition of the emulsifier”, that is, when the aging step is performed after abruptly reducing the cohesive force, once the cohesive force is suddenly decreased. The adhered resin fine particles may be easily detached. Therefore, it is preferable to fuse the resin fine particles after adhering them without significantly reducing the cohesive force and suppressing the particle diameter growth.

In the emulsion polymerization aggregation method, in order to increase the stability of the particle aggregate obtained by aggregation, an emulsifier and a pH adjuster are added as a dispersion stabilizer to reduce the aggregation force between the particles, thereby growing the toner base particles. It is preferable to add an aging step for causing fusion between the agglomerated particles after stopping.
The amount of the emulsifier is not limited, but is preferably 0.1 parts by weight or more, more preferably 1 part by weight or more, and further preferably 3 parts by weight or more with respect to 100 parts by weight of the solid component of the mixed dispersion. Moreover, it is preferably 20 parts by weight or less, more preferably 15 parts by weight or less, and still more preferably 10 parts by weight or less. After the aggregation process, before the completion of the ripening process, by adding an emulsifier or increasing the pH value of the flocculation liquid, aggregation of the particle aggregates aggregated in the aggregation process can be suppressed. The generation of coarse particles in the toner can be suppressed.

  Here, as a method for controlling the particle size within a specific range, which means that the particle size distribution is sharp in the color toner of the present invention, the stirring rotation speed is reduced before the step of adding an emulsifier or a pH adjuster, that is, And a method of lowering the shearing force by stirring. This method is preferably employed when a system having a weak aggregating action, such as an emulsifier or a pH adjuster, is added at a time to rapidly shift to a stable (dispersed) system. As described above, if a method of raising the temperature while adding an aqueous solution in which a dispersion stabilizer and water are mixed in advance is adopted, the system is too inclined to agglomerate when the stirring rotation speed is lowered, so that the particle size May lead to enlargement.

As an example, the toner having a specific particle size distribution according to the present invention can be obtained by the above-described method. More specifically, the content of fine powder particles can be adjusted by the degree to which the rotational speed is reduced. For example, when the stirring rotation speed is reduced from 250 rpm to 150 rpm, a toner having a smaller particle size with a sharper particle size distribution than that of a known toner can be provided, and the color toner having a specific particle size distribution of the present invention can be obtained. . However, this value is naturally
(A) The diameter of the stirring vessel (as a so-called general cylindrical shape) and the maximum diameter of the stirring blade (and its relative ratio)
(B) Height of stirring container
(C) Peripheral speed of the tip of the stirring blade
(D) Shape of stirring blade
(E) Position of the blades in the stirring vessel
It depends on the conditions. About special (c), 1.0-2.5 m / sec is preferable, 1.2-2.3 m / sec is more preferable, 1.5-2.2 m / sec is especially preferable. This is because, within the above range, a suitable shear rate that does not peel off and does not enlarge is given to the particles.

  The temperature of the aging step is preferably not less than Tg of the binder resin as the polymer primary particles, more preferably not less than 5 ° C higher than the Tg, and preferably not more than 80 ° C higher than the Tg, more preferably The temperature is 50 ° C. or higher than the Tg. The time required for the aging step varies depending on the shape of the target toner, but after reaching the glass transition temperature of the polymer constituting the polymer primary particles, usually 0.1 to 5 hours, preferably 1 to It is desirable to hold for 3 hours.

  By such a heat treatment, the polymer primary particles in the aggregate are fused and integrated, and the shape of the toner base particles as the aggregate becomes close to a spherical shape. The particle aggregate before the aging step is considered to be an aggregate due to electrostatic or physical aggregation of the polymer primary particles, but after the aging step, the polymer primary particles constituting the particle aggregate are fused to each other. In addition, the shape of the toner base particles can be made nearly spherical. According to such an aging process, by controlling the temperature and time of the aging process, the shape of the polymer primary particles is agglomerated, a potato type with advanced fusion, a spherical form with further fusion For example, various shapes of toner can be manufactured according to the purpose.

The particle aggregate obtained through each of the above steps is subjected to solid / liquid separation according to a known method, the particle aggregate is recovered, then washed as necessary, and then dried. Toner mother particles can be obtained.
Further, an outer layer mainly composed of a polymer is further formed on the surface of the particles obtained by the emulsion polymerization aggregation method, for example, by a spray drying method, an in-situ method, or a submerged particle coating method. It is also possible to obtain encapsulated toner base particles by forming them with a thickness of preferably 0.01 to 0.5 μm.

  Further, in the emulsion polymerization aggregation method toner, the average circularity measured using a flow type particle image analyzer FPIA-2100 is preferably 0.90 or more, more preferably 0.92 or more, and further preferably 0.94 or more. It is. It is considered that the closer to a sphere, the less the charge amount is localized in the particles, and the developability tends to be uniform. However, making a perfect spherical toner deteriorates the cleaning property, so the average circularity Is preferably 0.98 or less, more preferably 0.97 or less.

  Further, at least one of the peak molecular weights in the gel permeation chromatography (hereinafter sometimes abbreviated as “GPC”) of the tetrahydrofuran (THF) soluble part of the toner is preferably 30,000 or more, more preferably 40,000 or more. More preferably, it is 50,000 or more, preferably 200,000 or less, more preferably 150,000 or less, and still more preferably 100,000 or less. When the peak molecular weight is lower than the above range, the mechanical durability in the non-magnetic one-component development method may be deteriorated. When the peak molecular weight is higher than the above range, the low temperature fixability and the fixing strength are deteriorated. There is a case.

The chargeability of the emulsion polymerization aggregation method toner may be positively charged or negatively charged, but is preferably used as a negatively chargeable toner. Control of the chargeability of the toner can be adjusted by selection and content of a charge control agent, selection and blending amount of an external additive, and the like.
In order to obtain a toner satisfying the above formula (3), it is preferable to employ an operation in which the aggregation speed is not high compared to the operation normally performed in the aggregation step. Examples of operations that do not cause the aggregation speed to be high include, for example, cooling the dispersion to be used in advance, adding the dispersion over time, adopting an electrolyte that does not have a large aggregating action, continuously using the electrolyte, or There are methods such as intermittent addition, slowing the rate of temperature rise, and long aggregation time. In the aging step, it is preferable to adopt an operation in which the aggregated particles are difficult to redisperse. Examples of the operation in which the agglomerated particles are difficult to finely disperse include, for example, a method in which the number of revolutions for stirring is decreased, a dispersion stabilizer is added continuously or intermittently, and a dispersion stabilizer and water are mixed in advance. Further, the toner satisfying the above formula (3) does not go through a step of removing particles having a volume median diameter (Dv50) or less from the finally obtained toner or toner base particles by an operation such as classification. It is preferable to be obtained.

The color toner of the present invention is for a magnetic two-component developer that coexists with a carrier for conveying the toner to the electrostatic latent image portion by magnetic force, or for a non-magnetic one-component developer that does not use magnetic powder as a developer. However, it is particularly preferable to use as a developer for the non-magnetic one-component development system in order to express the effects of the present invention remarkably.
When used as the magnetic two-component developer, the carrier that is mixed with the toner to form the developer is a known magnetic substance such as an iron powder type, ferrite type, or magnetite type carrier, or a resin coating on the surface thereof. Or a magnetic resin carrier can be used. As the carrier coating resin, generally known styrene resins, acrylic resins, styrene acrylic copolymer resins, silicone resins, modified silicone resins, fluorine resins, and the like can be used, but are not limited thereto. It is not a thing. The average particle size of the carrier is not particularly limited, but preferably has an average particle size of 10 to 200 μm. These carriers are preferably used in an amount of 5 to 100 parts by weight with respect to 1 part by weight of the toner.

  The image forming method of the present invention will be described in more detail with reference to the drawings. FIG. 1 is an explanatory diagram showing an example of a developing device using a non-magnetic one-component toner that can be used for performing an image forming method using the toner of the present invention. In FIG. 1, the toner 6 of the present invention built in the toner hopper 7 is forcibly brought to a roller-like sponge roller (toner supply auxiliary member) 4 by the stirring blade 5, and the toner is supplied to the sponge roller 4. The The toner taken into the sponge roller 4 is carried to the toner conveying member 2 by the sponge roller 4 rotating in the direction of the arrow, and is rubbed and electrostatically or physically adsorbed. It rotates strongly in the direction of the arrow, and a uniform thin toner layer is formed by a steel elastic blade (toner layer thickness regulating member) 3 and is frictionally charged. Thereafter, the toner is conveyed to the surface of the electrostatic latent image carrier 1 that is in contact with the toner conveying member 2, and the latent image is developed. The electrostatic latent image is obtained, for example, by subjecting an organic photoreceptor to DC charging of 500 V and then exposure.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In the following examples, “parts” means “parts by weight”.
<Measurement method and definition of volume average diameter (Mv)>
The volume average diameter (Mv) of particles having a volume average diameter (Mv) of less than 1 μm is handled by using Nitraso Co., Ltd., model: Microtrac Nanotrac 150 (hereinafter abbreviated as “Nanotrack”). In accordance with the instructions, using the company's analysis software Microtrac Particle Analyzer Ver10.1.2.-019EE, using ion-exchanged water with an electric conductivity of 0.5 μS / cm as the dispersion medium, enter the following conditions or the following conditions respectively: And measured by the method described in the instruction manual.
For wax dispersion and polymer primary particle dispersion,
Solvent refractive index: 1.333
・ Measurement time: 100 seconds ・ Number of measurements: 1 time
-Particle refractive index: 1.59
・ Transparency: Transmission
・ Shape: Spherical shape
Density: 1.04
For pigment premix liquid and colorant dispersion,
Solvent refractive index: 1.333
・ Measurement time: 100 seconds
・ Number of measurements: 1 time
-Particle refractive index: 1.59
・ Permeability: Absorption
・ Shape: Non-spherical
・ Density: 1.00
<Measurement method and definition of volume median diameter (Dv50)>
As a pre-measurement treatment of the toner finally obtained through the external addition process, it was performed as follows. In a cylindrical polyethylene (PE) beaker having an inner diameter of 47 mm and a height of 51 mm, 0.100 g of toner using a spatula, 20% by weight DBS aqueous solution using a dropper (Daiichi Kogyo Seiyaku Co., Ltd., Neogen S-20A) 0.15 g was added. At this time, toner and a 20% DBS aqueous solution were added only to the bottom of the beaker so that the toner would not scatter on the edge of the beaker. Next, the mixture was stirred for 3 minutes using a spatula until the toner and 20% DBS aqueous solution became a paste. At this time, the toner was prevented from being scattered on the edge of the beaker.

  Subsequently, 30 g of dispersion medium Isoton II was added, and the mixture was stirred for 2 minutes using a spatula to obtain a uniform solution as a whole. Next, a fluororesin-coated rotor having a length of 31 mm and a diameter of 6 mm was placed in a beaker and dispersed using a stirrer at 400 rpm for 20 minutes. At this time, using a spatula at a rate of once every 3 minutes, macroscopic particles visually observed at the gas-liquid interface and the edge of the beaker were dropped into the beaker so as to form a uniform dispersion. Subsequently, this was filtered through a mesh having an opening of 63 μm, and the obtained filtrate was designated as “toner dispersion”.

Regarding the measurement of the particle diameter during the production process of the toner base particles, the filtrate obtained by filtering the agglomerated slurry with a 63 μm mesh was used as the “slurry liquid”.
The volume median diameter (Dv50) of the particles was Beckman Coulter's Multisizer III (aperture diameter 100 μm) (hereinafter abbreviated as “Multisizer”), the dispersion medium was Isoton II, and the above-mentioned Dilute the “toner dispersion” or “slurry” to a dispersoid concentration of 0.03% by mass, and set the KD value to 118.5 using Multisizer III analysis software (ver. ***). It was measured. The measurement particle diameter range is from 2.00 to 64.00 μm, and this range is discretized into 256 divisions so as to be equidistant on a logarithmic scale, and the volume calculated based on the statistical values on the basis of the volume is the volume. The median diameter (Dv50) was used.
<Measurement Method and Definition of Number% (Dns) of Toner with Particle Size of 2.00 μm to 3.56 μm>
As a pre-measurement process for the toner after the external addition step, the following procedure was performed. In a cylindrical polyethylene (PE) beaker having an inner diameter of 47 mm and a height of 51 mm, 0.100 g of toner using a spatula, 20% by weight DBS aqueous solution using a dropper (Daiichi Kogyo Seiyaku Co., Ltd., Neogen S-20A) 0.15 g was added. At this time, toner and a 20% DBS aqueous solution were added only to the bottom of the beaker so that the toner would not scatter on the edge of the beaker. Next, the mixture was stirred for 3 minutes using a spatula until the toner and 20% DBS aqueous solution became a paste. At this time, the toner was prevented from being scattered on the edge of the beaker.

Subsequently, 30 g of dispersion medium Isoton II was added, and the mixture was stirred for 2 minutes using a spatula, and the whole was made into a uniform solution visually. Next, a fluororesin-coated rotor having a length of 31 mm and a diameter of 6 mm was placed in a beaker and dispersed using a stirrer at 400 rpm for 20 minutes. At this time, macroscopic particles visually observed at the gas-liquid interface and the edge of the beaker were dropped into the beaker at a rate of once every 3 minutes so as to form a uniform dispersion. Subsequently, this was filtered with a mesh having an opening of 63 μm, and the obtained filtrate was used as a toner dispersion.

For the number% (Dns) of toner having a particle size of 2.00 μm or more and 3.56 μm or less, a multisizer (aperture diameter 100 μm) is used, and Isoton II manufactured by the same company is used as a dispersion medium. The “slurry liquid” was diluted to a dispersoid concentration of 0.03% by mass and measured with Multisizer III analysis software with a KD value of 118.5.
The lower limit particle size of 2.00 μm is the detection limit of the measurement device multisizer, and the upper limit particle size of 3.56 μm is the prescribed value of the channel in the measurement device multisizer. In the present invention, the region having a particle size of 2.00 μm or more and 3.56 μm or less is recognized as a fine powder region.

The measurement particle diameter range is from 2.00 to 64.00 μm, and this range is discretized into 256 divisions so as to be equally spaced on a logarithmic scale. The ratio of the particle size component from 3 to 3.56 μm was calculated on the basis of the number to be “Dns”.
<Measuring method and definition of average circularity>
The “average circularity” in the present invention is measured as follows and is defined as follows. That is, the toner base particles are dispersed in a dispersion medium (Isoton II, manufactured by Beckman Coulter, Inc.) so as to be in the range of 5720-7140 particles / μL, and a flow type particle image analyzer (Sysmex Corporation (formerly Toa Medical Electronics)). (Manufactured by FPIA 2100), measurement is performed under the following apparatus conditions, and the value is defined as “average circularity”. In the present invention, the same measurement is performed three times, and an arithmetic average value of three “average circularity” is adopted as the “average circularity”.
・ Mode: HPF
-HPF analysis amount: 0.35 μL
-HPF detection number: 2000-2500
The following is measured by the above device and automatically calculated and displayed in the above device, and “circularity” is defined by the following formula.

[Circularity] = [Perimeter of a circle with the same area as the projected particle area] / [Perimeter of projected particle image]
And 2000-2500 which is the number of HPF detection is measured, and the arithmetic average (arithmetic mean) of the circularity of each individual particle is displayed on the apparatus as “average circularity”.
<Measurement method and definition of number variation coefficient>
The number variation coefficient is expressed by standard deviation of number-based particle distribution × 100 / number average particle diameter. The particle size distribution of the present invention was measured as follows.

The particle number coefficient of variation is Beckman Coulter's Multisizer III (aperture diameter 100 μm) (hereinafter abbreviated as “Multisizer”), the dispersion medium is Isoton II, and the above “toner dispersion” Alternatively, the “slurry liquid” is diluted to a dispersoid concentration of 0.03% by mass, and the KD value is 1 with Multisizer III analysis software (V3.51).
It was measured as 18.5. The measurement particle size range is from 2.00 to 64.00 μm, and this range is discretized into 256 divisions at equal intervals on a logarithmic scale, and the number calculated based on the statistical value on the basis of the number is used. The coefficient of variation was used.
<Method of measuring electrical conductivity>
The electrical conductivity was measured using a conductivity meter (a personal SC meter model SC72 and a detector SC72SN-11 manufactured by Yokogawa Electric Corporation) according to an ordinary method according to the instruction manual.
<Measuring method of melting point peak temperature, melting peak half width, crystallization temperature, crystallization peak half width>
From the endothermic curve when the temperature is raised from 10 ° C. to 110 ° C. at a rate of 10 ° C./min using the method described in the company's instruction manual using Seiko Instruments Inc. model: SSC5200, the melting point peak temperature The half-width of the melting peak was measured, and then the crystallization temperature and the half-width of the crystallization peak were measured from the exothermic curve when the temperature was lowered from 110 ° C. to 10 ° C. at a rate of 10 ° C./min.
<Measurement method of solid content concentration>
Using a solid content concentration measuring instrument INFRARED MOISTURE DETERMINATION BALANCE model FD-100, manufactured by Kett Science Laboratory, weighed 1.00 g of a sample containing solid content on a balance, and the conditions of a heater temperature of 300 ° C. and a heating time of 90 minutes The solid content concentration was measured.
<Method of live-action evaluation>
Actual photograph evaluation 100 g of toner is a non-magnetic one component (using organic photoreceptor), roller charging, rubber development roller contact development method, development speed 164 mm / second, tandem method, belt conveyance method, direct transfer method, blade drum cleaning method, It was loaded into a cartridge of a 600 dpi machine with a guaranteed life of 30,000 sheets at 5% printing rate, and 50 charts of 1% printing rate were continuously printed.
<Dirt>
In the above-mentioned actual image evaluation, the smear of the image after printing 50 sheets was visually observed and judged according to the following criteria.

A: No dirt at all
○: Slightly dirty but usable level
Δ: Partially dirty
X: Dirt can be clearly confirmed partially or entirely.
<Afterimage (Ghost)>
In the actual image evaluation, a solid image was printed, and the image density of the tip portion and the image density of the portion printed after two rotations from the developing roller were measured with X-rite 938 (manufactured by X-Rite), respectively. The ratio (%) of the image density after two rounds to the tip portion was obtained.

A: No problem at all (98% or more)
○: Level that can be used although there is a slight difference in image density (95% or more and less than 98%)
Δ: Level that can be recognized as having a slight difference in image density (85% or more and less than 95%)
X: Level with a clear difference in image density (less than 85%)
<Gloss>
The paper on which the solid image was printed was set at a predetermined measurement site of a gloss meter (VG2000 manufactured by Nippon Denshoku Industries Co., Ltd.). The light transmission / reception angle was fixed at 75 °, and the gloss was measured at three places on the solid image to calculate the average value. Furthermore, another solid image was printed, the same measurement was performed to calculate the average value, and the average value of the two solid image measurement values was calculated to obtain the gloss value.
<Measurement method of toner surface potential>
After the toner was triboelectrically charged under a fixed condition where 10 solid toner images were printed, the toner cartridge was quickly removed from the image forming apparatus. A part of the protective cover of the cartridge was removed to expose the OPC drum and the developing roller. The toner was attached to the entire surface of the developing roller. After calibrating the measurement probe of the surface potential meter (MODEL 344, manufactured by Trek Japan Co., Ltd.) to 0 volts, the probe was brought close to a position just before contact with the developing roller, and the surface potential of the toner was measured. The surface potential of the toner was determined by measuring three locations in total, one at the center and the other along the axis of the developing roller, and averaging the values.

Example 1
<Preparation of charge control agent dispersion α>
10 parts of powder of charge control agent E-81 (manufactured by Orient Chemical Co., Ltd.), 10 parts of anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen S-20A) in a 1 L stainless beaker with a stirring blade set, 80 parts of ion-exchanged water having an electric conductivity of 2 μS / cm was added and well mixed by stirring, and a charge control agent premix solution was obtained by preliminary dispersion.

  The premix solution was dispersed as a raw material slurry using a wet bead mill (a batch type tabletop sand mill manufactured by Kansai Paint Co., Ltd.). As dispersion media, zirconia beads having a diameter of 300 μm (true density 6.0 g / cm 3) were used and mixed with the raw material slurry 1 at a weight ratio of 5 to a total amount of 1200 g. A stainless steel disc-shaped stirring blade with a diameter of 7 cm and a thickness of 0.6 cm is fixed along the rotation center axis of the bead mill, and the premix solution is placed so that the blade is sufficiently immersed in the mixture of raw material slurry and beads. I set a beaker. This beaker was immersed in a constant temperature water bath, and 10 ° C. cooling water was circulated by a constant temperature cooler during the bead mill operation. The number of revolutions of the stirring blade was made constant at 1490 rpm, and the mixture was stirred for about 1 hour to obtain a dispersion when the particle size reached a predetermined level.

  The beads and filtrate were completely separated with a 100 mesh stainless steel sieve to obtain a charge control agent dispersion. This dispersion was diluted with UPA (manufactured by Nikkiso Co., Ltd., UPA-150) to an appropriate concentration in water in which several μL of the above anionic surfactant was dropped, and the particle size distribution of the particles was measured in a measurement time of 100 seconds. did. The volume particle size distribution median diameter of the obtained particles was 200 nm.

<Preparation of wax / long-chain polymerizable monomer dispersion A1>
Paraffin wax (Nihon Seiki Co., Ltd. HNP-9, surface tension 23.5 mN / m, thermal characteristics: melting point peak temperature 82 ° C., melting heat 220 J / g, melting peak half width 8.2 ° C., crystallization temperature 66 ° C., Crystallization peak half width 13.0 ° C.) 27 parts (540 g), stearyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) 2.8 parts, 20 mass% sodium dodecylbenzenesulfonate aqueous solution (Daiichi Kogyo Seiyaku Co., Ltd., Neogen S20A) ( (Hereinafter abbreviated as “20% DBS aqueous solution”) 1.9 parts and 68.3 parts of demineralized water are heated to 90 ° C. and used for 10 minutes using a homomixer (Mark II f model manufactured by Tokushu Kika Kogyo Co., Ltd.). Stir.

  Next, this dispersion was heated to 90 ° C., and circulation emulsification was started under a pressure condition of 25 MPa using a homogenizer (manufactured by Gorin, 15-M-8PA type). Dispersion was carried out until (Mv) reached 250 nm to prepare a wax / long-chain polymerizable monomer dispersion A1 (emulsion solid content concentration = 30.2 mass%).

<Preparation of polymer primary particle dispersion A1>
In a reactor (inner volume 21 L, inner diameter 250 mm, height 420 mm) equipped with a stirrer (three blades), a heating / cooling device, a concentrating device, and a raw material / auxiliary charging device, the wax / long-chain polymerizable unit is added. The monomer dispersion A1 (35.6 parts, 712.12 g) and 259 parts of demineralized water were charged, and the temperature was raised to 90 ° C. under a nitrogen stream while stirring.

  Thereafter, the mixture of the following “polymerizable monomers and the like” and “emulsifier aqueous solution” was added to the solution over 5 hours while continuing to stir the liquid. The time at which this mixture was started to be dropped was designated as “polymerization start”, and the following “initiator aqueous solution” was added over 4.5 hours from 30 minutes after the start of polymerization. Further, after 5 hours from the start of polymerization, the following “additional start” The agent aqueous solution ”was added over 2 hours, and the internal temperature was maintained at 90 ° C. for 1 hour while continuing stirring.

[Polymerizable monomers, etc.]
Styrene 76.8 parts (1535.0 g)
23.2 parts butyl acrylate
Acrylic acid 1.5 parts
Hexanediol diacrylate 0.7 parts
1.0 part of trichlorobromomethane

[Emulsifier aqueous solution]
20% DBS aqueous solution 1.0 part
67.1 parts of demineralized water

[Initiator aqueous solution]
15.5 parts of 8% by weight aqueous hydrogen peroxide solution
15.5 parts of 8 mass% L (+)-ascorbic acid aqueous solution

[Additional initiator aqueous solution]
8 mass% L (+)-ascorbic acid aqueous solution 14.2 parts

  After the completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle dispersion A1. The volume average diameter (Mv) measured using Nanotrac was 280 nm, and the solid content concentration was 21.1% by mass.

<Preparation of polymer primary particle dispersion A2>
In a reactor (inner volume 21 L, inner diameter 250 mm, height 420 mm) equipped with a stirrer (three blades), a heating / cooling device, a concentrating device, and each raw material / auxiliary charging device, 1.0 part of a 20 mass% DBS aqueous solution Then, 312 parts of demineralized water was added, the temperature was raised to 90 ° C. under a nitrogen stream, and 3.2 parts of an 8% by mass hydrogen peroxide aqueous solution and 3.2 parts of an 8% by mass L (+)-ascorbic acid aqueous solution were stirred. Added all at once. The time point 5 minutes after the batch addition of these is defined as “polymerization start”.

  A mixture of the following “polymerizable monomers etc.” and “emulsifier aqueous solution” was added over 5 hours from the start of polymerization, and the following “initiator aqueous solution” was added over 6 hours from the start of polymerization. While stirring, the internal temperature was maintained at 90 ° C. for 1 hour.

[Polymerizable monomers, etc.]
92.5 parts of styrene (1850.0 g)
7.5 parts butyl acrylate
Acrylic acid 0.5 part
0.5 parts of trichlorobromomethane

[Emulsifier aqueous solution]
1.5 parts of 20% DBS aqueous solution
66.0 parts of demineralized water

[Initiator aqueous solution]
18.9 parts of 8% hydrogen peroxide solution
8% by mass L (+)-ascorbic acid aqueous solution 18.9 parts

  After completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle dispersion A2. The volume average diameter (Mv) measured using Nanotrac was 290 nm, and the solid content concentration was 19.0% by mass.

<Preparation of colorant dispersion (quinacridone)>
In a container with an internal volume of 300 L equipped with a stirrer (propeller blade), 20 parts (40 kg) of quinacridone (manufactured by Clariant Japan, Hosterperm Pin E-WD), 1 part of 20% DBS aqueous solution, nonionic surfactant (manufactured by Kao Corporation) , Emulgen 120), and 75 parts of ion-exchanged water having an electric conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. The volume average diameter (Mv) of quinacridone in the dispersion after pigment premixing measured with Nanotrac was about 90 μm.

The pigment premix solution was supplied as a raw material slurry to a wet bead mill and circulated and dispersed. The inner diameter of the stator was φ75 mm, the separator diameter was φ60 mm, the distance between the separator and the disk was 15 mm, and zirconia beads having a diameter of 50 μm (true density 6.0 g / cm ³ ) were used as the dispersing medium. Since the effective internal volume of the stator is 0.5 L and the filling volume of the media is 0.35 L, the media filling rate is 70% by mass. The pigment premix liquid is continuously supplied from the supply port at a supply speed of 50 L / hr by a non-pulsating metering pump, and the rotor rotation speed is constant (peripheral speed at the rotor tip is 11 m / sec), and continuously from the discharge port. The colorant dispersion (quinacridone) was obtained when it reached a predetermined particle size by being repeatedly circulated. The volume average diameter (Mv) of the colorant dispersion (quinacridone) measured with Nanotrac was 243 nm, and the solid content concentration was 24.2% by mass.

<Manufacture of toner mother particles K>
Using the following components, toner base particles A were produced by carrying out the following aggregation processes (core material aggregation process, shell coating process), circularization process, washing process, and drying process.
Polymer primary particle dispersion A1 95 parts as solid content (998.2 g as solid content)
Polymer primary particle dispersion A2 5 parts as solid content
Colorant dispersion (quinacridone) 9 parts as colorant solids
20% DBS aqueous solution In the core material agglomeration process, the solid content is 0.2 parts.
20% DBS aqueous solution In the rounding process, 6 parts as solid content

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 7.11 μm.

○ Shell coating process
Thereafter, a liquid obtained by mixing 0.3 part of the polymer primary particle dispersion A2 and the charge control agent dispersion α was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation number of 250 rpm, and the state was maintained for 60 minutes. .

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.944. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

○ Cleaning process
The obtained slurry was extracted and subjected to suction filtration with an aspirator using filter paper of type 5 C (No5C manufactured by Toyo Roshi Kaisha, Ltd.). The cake remaining on the filter paper is transferred to a stainless steel container having an internal volume of 10 L equipped with a stirrer (propeller blade), and 8 kg of ion exchange water having an electric conductivity of 1 μS / cm is added and stirred uniformly at 50 rpm. Thereafter, stirring was continued for 30 minutes.

  Thereafter, the filter paper was suction filtered with an aspirator again using Type 5 C (Toyo Filter Paper No. 5C) filter paper, and the solid matter remaining on the filter paper was again equipped with a stirrer (propeller blade) and had an electrical conductivity of 1 μS / cm. It was transferred to a container with an internal volume of 10 L containing 8 kg of ion-exchanged water, and uniformly dispersed by stirring at 50 rpm and kept stirring for 30 minutes. When this process was repeated 5 times, the electrical conductivity of the filtrate was 2 μS / cm.

○ Drying process
The solid material obtained here was spread on a stainless steel bat so as to have a height of 20 mm, and dried in a blow dryer set at 40 ° C. for 48 hours, whereby toner base particles K were obtained.

<Manufacture of toner K>
○ External process
To the obtained toner base particles K250 g, 1.41 g of H2000 silica manufactured by Clariant Co. and 0.56 g of SMT150IB titania fine powder manufactured by Teika Co., Ltd. were mixed as external additives, and 1 at 6000 rpm with a sample mill (manufactured by Kyoritsu Riko Co., Ltd.). The resulting mixture was mixed for 1 minute and sieved with 150 mesh to obtain toner K.
○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of toner K obtained here is 7.11 μm, and “number% (Dns) of toner having a particle size of 2.00 μm to 3.56 μm” is The average circularity was 0.943 and the number variation coefficient was 19.2%. Further, the gloss value of the solid image was 26.4, and the toner surface potential on the developing roller was −33V. The above results are summarized in Table 1.

Example 2
<Preparation of Charge Control Agent Dispersion β>
10 parts of powder of charge control agent TN-105 (Hodogaya Chemical Co., Ltd.), 10 parts of anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen S-20A) in a 1 L stainless beaker with a stirring blade set Then, 80 parts of ion-exchanged water having an electric conductivity of 2 μS / cm was added and well mixed with stirring, and a charge control agent premix solution was obtained by preliminary dispersion.

  The premix solution was dispersed as a raw material slurry using a wet bead mill (a batch type tabletop sand mill manufactured by Kansai Paint Co., Ltd.). As dispersion media, zirconia beads having a diameter of 300 μm (true density 6.0 g / cm 3) were used and mixed with the raw material slurry 1 at a weight ratio of 5 to a total amount of 1200 g. A stainless steel disc-shaped stirring blade with a diameter of 7 cm and a thickness of 0.6 cm is fixed along the rotation center axis of the bead mill, and the premix solution is placed so that the blade is sufficiently immersed in the mixture of raw material slurry and beads. I set a beaker. This beaker was immersed in a constant temperature water bath, and 10 ° C. cooling water was circulated by a constant temperature cooler during the bead mill operation. The number of revolutions of the stirring blade was made constant at 1490 rpm, and the mixture was stirred for about 1 hour to obtain a dispersion when the particle size reached a predetermined level.

The beads and filtrate were completely separated with a 100 mesh stainless steel sieve to obtain a charge control agent dispersion. This dispersion was diluted with UPA (manufactured by Nikkiso Co., Ltd., UPA-150) to an appropriate concentration in water in which several μL of the above anionic surfactant was dropped, and the particle size distribution of the particles was measured in a measurement time of 100 seconds. did. The volume particle size distribution median diameter of the obtained particles was 160 nm.
<Manufacture of toner mother particles L>
The component of the toner base particle K is 9.0 parts of the colorant dispersion quinacridone, and the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing the toner base particle K” 1 except that the “core material agglomeration step”, “shell coating step” and “circularization step” were changed as described below in the same manner as in “Production of toner mother particles K” in Example 1. Particles L were obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 7.25 μm.

○ Shell coating process
Thereafter, a liquid obtained by mixing 0.3 part of the polymer primary particle dispersion A2 and the charge control agent dispersion β was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed of 250 rpm, and held as it was for 60 minutes. .

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.944. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacture of toner L>
Thereafter, the toner L was changed by the same external addition process as in “Production of Toner K” except that the amount of H2000 silica as an external additive was changed to 1.41 g and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of the toner L obtained here is 7.25 μm, and “the number% (Dns) of toner having a particle size of 2.00 μm to 3.56 μm” is The average circularity was 0.944 and the number variation coefficient was 18.9%. Further, the gloss value of the solid image was 26.4, and the toner surface potential on the developing roller was −35V. The above results are summarized in Table 1.

Example 3
<Manufacture of toner mother particles M>
The component of the toner base particle K is 9.0 parts of the colorant dispersion quinacridone, and the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing the toner base particle K” 1 except that the “core material agglomeration step”, “shell coating step” and “circularization step” were changed as described below in the same manner as in “Production of toner mother particles K” in Example 1. Particle M was obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, and the volume median diameter (Dv50) was measured using a multisizer to grow to 7.05 μm.

○ Shell coating process
Thereafter, a liquid obtained by mixing 0.5 part of the polymer primary particle dispersion A2 and the charge control agent dispersion β was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed of 250 rpm, and held for 60 minutes. .

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.943. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacture of toner M>
Thereafter, the toner M was prepared in the same manner as in “Production of Toner K” except that the amount of H2000 silica as an external additive was changed to 1.41 g and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured by using the multisizer of the toner M obtained here is 7.05 μm, and “the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm” is The average circularity was 0.943 and the number variation coefficient was 19.6%. Further, the gloss value of the solid image was 29.5, and the toner surface potential on the developing roller was −34V. The above results are summarized in Table 1.

Example 4
<Preparation of Charge Control Agent Dispersion γ>
10 parts powder of charge control agent T-77 (made by Hodogaya Chemical Co., Ltd.) and 10 parts anionic surfactant (made by Daiichi Kogyo Seiyaku Co., Ltd., Neogen S-20A) in a 1 L stainless beaker with a stirring blade set Then, 80 parts of ion-exchanged water having an electric conductivity of 2 μS / cm was added and well mixed with stirring, and a charge control agent premix solution was obtained by preliminary dispersion.

  The premix solution was dispersed as a raw material slurry using a wet bead mill (a batch type tabletop sand mill manufactured by Kansai Paint Co., Ltd.). As dispersion media, zirconia beads having a diameter of 300 μm (true density 6.0 g / cm 3) were used and mixed with the raw material slurry 1 at a weight ratio of 5 to a total amount of 1200 g. A stainless steel disc-shaped stirring blade with a diameter of 7 cm and a thickness of 0.6 cm is fixed along the rotation center axis of the bead mill, and the premix solution is placed so that the blade is sufficiently immersed in the mixture of raw material slurry and beads. I set a beaker. This beaker was immersed in a constant temperature water bath, and 10 ° C. cooling water was circulated by a constant temperature cooler during the bead mill operation. The number of revolutions of the stirring blade was made constant at 1490 rpm, and the mixture was stirred for about 1 hour to obtain a dispersion when the particle size reached a predetermined level.

The beads and filtrate were completely separated with a 100 mesh stainless steel sieve to obtain a charge control agent dispersion. This dispersion was diluted with UPA (manufactured by Nikkiso Co., Ltd., UPA-150) to an appropriate concentration in water in which several μL of the above anionic surfactant was dropped, and the particle size distribution of the particles was measured in a measurement time of 100 seconds. did. The volume particle size distribution median diameter of the obtained particles was 180 nm.
<Manufacture of toner mother particles N>
The component of the toner base particle K is 9.0 parts of the colorant dispersion quinacridone, and the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing the toner base particle K” 1 except that the “core material agglomeration step”, “shell coating step” and “circularization step” were changed as described below in the same manner as in “Production of toner mother particles K” in Example 1. Particle N was obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 6.91 μm.

○ Shell coating process
Thereafter, with an internal temperature of 55.0 ° C. and a rotational speed of 250 rpm, a liquid in which 1.0 part of the polymer primary particle dispersion A2 and the charge control agent dispersion γ was mixed was added over 3 minutes and held for 60 minutes. .

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.943. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacture of toner N>
Thereafter, the amount of H2000 silica as an external additive was changed to 1.41 g, and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of the toner N obtained here is 6.91 μm, and “number% (Dns) of toner having a particle size of 2.00 μm to 3.56 μm” is The average circularity was 0.948 and the number variation coefficient was 22.3%. The gloss value of the solid image was 30.7, and the toner surface potential on the developing roller was −30V. The above results are summarized in Table 1.

Example 5
<Manufacture of toner mother particles O>
The component of the toner base particle K is 9.0 parts of the colorant dispersion quinacridone, and the agglomeration step (core material agglomeration step / shell coating step), circularization step, washing step, drying step 1 except that the “core material agglomeration step”, “shell coating step” and “circularization step” were changed as described below in the same manner as in “Production of toner mother particles K” in Example 1. Particle O was obtained.
○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 6.71 μm.
○ Shell coating process
Thereafter, the polymer primary particle dispersion A2 was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed at 250 rpm, and held as it was for 60 minutes.
○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.945. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.
<Manufacture of toner O>
Thereafter, the toner O2 was changed to 1.41 g as an external additive, and the toner O O was prepared by the same external addition process as in “Production of Toner K” except that the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.
○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of the toner O obtained here is 6.71 μm, and “the number% (Dns) of toner having a particle size of 2.00 μm to 3.56 μm” is The average circularity was 0.945 and the number variation coefficient was 20.5%. The gloss value of the solid image was 30.4, and the toner surface potential on the developing roller was −36V.
Comparative Example 1
<Preparation of Charge Control Agent Dispersion δ>
10 parts powder of charge control agent E-84 (manufactured by Orient Chemical Co., Ltd.), 10 parts of an anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen S-20A) in a 1 L stainless beaker set with a stirring blade, 80 parts of ion-exchanged water having an electric conductivity of 2 μS / cm was added and well mixed by stirring. A charge control agent premix solution was obtained by preliminary dispersion.

  The premix solution was dispersed as a raw material slurry using a wet bead mill (a batch type tabletop sand mill manufactured by Kansai Paint Co., Ltd.). As dispersion media, zirconia beads having a diameter of 300 μm (true density 6.0 g / cm 3) were used and mixed with the raw material slurry 1 at a weight ratio of 5 to a total amount of 1200 g. A stainless steel disc-shaped stirring blade with a diameter of 7 cm and a thickness of 0.6 cm is fixed along the rotation center axis of the bead mill, and the premix solution is placed so that the blade is sufficiently immersed in the mixture of raw material slurry and beads. I set a beaker. This beaker was immersed in a constant temperature water bath, and 10 ° C. cooling water was circulated by a constant temperature cooler during the bead mill operation. The number of revolutions of the stirring blade was kept constant at 525 rpm, and the mixture was stirred for about 0.5 hours to obtain a dispersion when the particle size reached a predetermined level.

  The beads and filtrate were completely separated with a 100 mesh stainless steel sieve to obtain a charge control agent dispersion. This dispersion was diluted with UPA (manufactured by Nikkiso Co., Ltd., UPA-150) to an appropriate concentration in water in which several μL of the above anionic surfactant was dropped, and the particle size distribution of the particles was measured in a measurement time of 100 seconds. did. The volume particle size distribution median diameter of the obtained particles was 650 nm.

<Manufacture of toner mother particles P>
The component of the toner base particle K is 9.0 parts of the colorant dispersion quinacridone, and the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing the toner base particle K” 1 except that the “core material agglomeration step”, “shell coating step” and “circularization step” were changed as described below in the same manner as in “Production of toner mother particles K” in Example 1. Particles P were obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 6.60 μm.

○ Shell coating process
Thereafter, a liquid in which 1.0 part of the polymer primary particle dispersion A2 and the charge control agent dispersion δ was mixed was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed at 250 rpm, and the mixture was held as it was for 60 minutes. .

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / sec at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.936. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacture of toner P>
Thereafter, the toner P was prepared by the same external addition process as in “Production of Toner K” except that the amount of H2000 silica as an external additive was changed to 1.41 g and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of the toner P obtained here is 6.60 μm, and “the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm” is The average circularity was 0.936 and the number variation coefficient was 21.8%. Further, the gloss value of the solid image was 32.8, and the toner surface potential on the developing roller was −28V. The above results are summarized in Table 1.

Comparative Example 2
<Preparation of charge control agent dispersion ε>
10 parts of powder of charge control agent TN-105 (Hodogaya Chemical Co., Ltd.), 10 parts of anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen S-20A) in a 1 L stainless beaker with a stirring blade set Then, 80 parts of ion-exchanged water having an electric conductivity of 2 μS / cm was added and well mixed with stirring, and a charge control agent premix solution was obtained by preliminary dispersion.

The premix solution was dispersed as a raw material slurry using a wet bead mill (a batch type tabletop sand mill manufactured by Kansai Paint Co., Ltd.). As dispersion media, zirconia beads having a diameter of 300 μm (true density 6.0 g / cm 3) were used and mixed with the raw material slurry 1 at a weight ratio of 5 to a total amount of 1200 g. A stainless steel disc-shaped stirring blade with a diameter of 7 cm and a thickness of 0.6 cm is fixed along the rotation center axis of the bead mill, and the premix solution is placed so that the blade is sufficiently immersed in the mixture of raw material slurry and beads. I set a beaker. This beaker was immersed in a constant temperature water bath, and 10 ° C. cooling water was circulated by a constant temperature cooler during the bead mill operation. The number of revolutions of the stirring blade was kept constant at 525 rpm, and the mixture was stirred for about 0.5 hours to obtain a dispersion when a predetermined particle size was reached.

  The beads and filtrate were completely separated with a 100 mesh stainless steel sieve to obtain a charge control agent dispersion. This dispersion was diluted with UPA (manufactured by Nikkiso Co., Ltd., UPA-150) to an appropriate concentration in water in which several μL of the above anionic surfactant was dropped, and the particle size distribution of the particles was measured in a measurement time of 100 seconds. did. The volume particle size distribution median diameter of the obtained particles was 550 nm.

<Manufacture of toner mother particles Q>
The component of the toner base particle K is 9.0 parts of the colorant dispersion quinacridone, and the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing the toner base particle K” 1 except that the “core material agglomeration step”, “shell coating step” and “circularization step” were changed as described below in the same manner as in “Production of toner mother particles K” in Example 1. Particle Q was obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 6.83 μm.

○ Shell coating process
Thereafter, a liquid obtained by mixing 1.0 part of the polymer primary particle dispersion A2 and the charge control agent dispersion ε was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation number of 250 rpm, and the mixture was held as it was for 60 minutes. .

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.944. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacture of toner Q>
Thereafter, the toner Q was changed to 1.41 g as an external additive, and the toner Q was changed by the same external addition process as in “Production of toner K” except that the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume-median diameter (Dv50) of the toner Q obtained using the multisizer obtained here is 6.83 μm, and “number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm” is The average circularity was 0.944 and the number variation coefficient was 22.8%. Further, the gloss value of the solid image was 32.9, and the toner surface potential on the developing roller was −27V.

Example 6

<Preparation of colorant dispersion (monoazo yellow)>
In a container with a volume of 300 L equipped with a stirrer (propeller blade), 20 parts (40 kg) of monoazo yellow (manufactured by Clariant Japan, 5GX01), 1 part of a 20% DBS aqueous solution, nonionic surfactant (manufactured by Kao Corporation, Emulgen 120 ) 4 parts, 75 parts of ion-exchanged water having an electric conductivity of 2 μS / cm was added and predispersed to obtain a pigment premix solution. The volume average diameter (Mv) of monoazo yellow in the dispersion after pigment premixing measured with Nanotrac was 100 μm.

The pigment premix solution was supplied as a raw material slurry to a wet bead mill and circulated and dispersed. The inner diameter of the stator was φ75 mm, the separator diameter was φ60 mm, the distance between the separator and the disk was 15 mm, and zirconia beads having a diameter of 50 μm (true density 6.0 g / cm ³ ) were used as the dispersing medium. Since the effective internal volume of the stator is 0.5 L and the filling volume of the media is 0.35 L, the media filling rate is 70% by mass. The pigment premix liquid is continuously supplied from the supply port at a supply speed of 50 L / hr by the non-pulsating metering pump, and the rotor rotation speed is constant (peripheral speed at the rotor tip is 11 m / sec), and continuously from the discharge port. The colorant dispersion (monoazo yellow) was obtained when it reached a predetermined particle size by being repeatedly circulated. The volume average diameter (Mv) of the colorant dispersion (monoazo yellow) measured with Nanotrac was 183 nm, and the solid content concentration was 24.0% by mass.
<Manufacture of toner mother particle R>
The component of the toner base particle K is 6.0 parts of a colorant dispersion monoazo yellow, and the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying of “manufacturing the toner base particle K”. In the process, except that the “core material aggregating process”, “shell coating process” and “circularization process” were changed as follows, the toner was prepared in the same manner as in “Production of toner base particles K” in Example 1. Base particles R were obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.72 μm.

○ Shell coating process
Thereafter, a liquid obtained by mixing 0.3 part of the polymer primary particle dispersion A2 and the charge control agent dispersion β was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed of 250 rpm, and held as it was for 60 minutes. .

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.944. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacturing Toner R>
Thereafter, the toner R was changed in the same manner as in “Production of Toner K” except that the amount of H2000 silica as an external additive was changed to 1.41 g and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of toner R obtained here is 5.72 μm, and “number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm” is The gloss value of the solid image was 29.6, and the toner surface potential on the developing roller was −33V. The average circularity was 0.944, and the number variation coefficient was 18.8%.

Example 7

<Preparation of colorant dispersion (phthalocyanine blue)>
In a container with an internal volume of 300 L equipped with a stirrer (propeller blade), 20 parts (40 kg) of phthalocyanine blue (manufactured by Clariant Japan, Hostaperm Blue B2G), 1 part of a 20% DBS aqueous solution, nonionic surfactant (manufactured by Kao Corporation, 4 parts of Emulgen 120) and 75 parts of ion-exchanged water having an electric conductivity of 2 μS / cm were added and predispersed to obtain a pigment premix solution. The volume average diameter (Mv) of phthalocyanine blue in the dispersion after pigment premixing measured with Nanotrac was about 90 μm.

The pigment premix solution was supplied as a raw material slurry to a wet bead mill and circulated and dispersed. The inner diameter of the stator was φ75 mm, the separator diameter was φ60 mm, the distance between the separator and the disk was 15 mm, and zirconia beads having a diameter of 50 μm (true density 6.0 g / cm ³ ) were used as the dispersing medium. Since the effective internal volume of the stator is 0.5 L and the filling volume of the media is 0.35 L, the media filling rate is 70% by mass. The pigment premix liquid is continuously supplied from the supply port at a supply speed of 50 L / hr by the non-pulsating metering pump, and the rotor rotation speed is constant (peripheral speed at the rotor tip is 11 m / sec), and continuously from the discharge port. The colorant dispersion (phthalocyanine blue) was obtained when it reached a predetermined particle size by being repeatedly circulated. The volume average diameter (Mv) of the colorant dispersion (phthalocyanine blue) measured with Nanotrac was 131 nm, and the solid content concentration was 24.1% by mass.
<Manufacture of toner mother particles S>
The component of the toner base particle K is 4.4 parts of a colorant dispersion phthalocyanine blue, and the aggregation process (core material aggregation process / shell coating process), circularization process, washing process, and drying of “manufacturing the toner base particle K” In the process, except that the “core material aggregating process”, “shell coating process” and “circularization process” were changed as follows, the toner was prepared in the same manner as in “Production of toner base particles K” in Example 1. Base particles S were obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.85 μm.

○ Shell coating process
Thereafter, a liquid obtained by mixing 0.3 part of the polymer primary particle dispersion A2 and the charge control agent dispersion β was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed of 250 rpm, and held as it was for 60 minutes. .

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.944. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacturing Toner S>
Thereafter, the toner S was prepared in the same manner as in “Production of Toner K” except that the amount of H2000 silica as an external additive was changed to 1.41 g and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured by using the multisizer of the toner S obtained here is 5.85 μm, and “number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm” is The average circularity was 0.944 and the number variation coefficient was 19%. Further, the gloss value of the solid image was 28.9, and the toner surface potential on the developing roller was −35V.

Comparative Example 3
<Manufacture of toner mother particles T>
The component of the toner base particle K is 6.0 parts of a colorant dispersion monoazo yellow, and the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying of “manufacturing the toner base particle K”. In the process, except that the “core material aggregating process”, “shell coating process” and “circularization process” were changed as follows, the toner was prepared in the same manner as in “Production of toner base particles K” in Example 1. Base particles T were obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.94 μm.

○ Shell coating process
Thereafter, the polymer primary particle dispersion A2 was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed at 250 rpm, and held as it was for 60 minutes.

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / sec at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.938. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacturing Toner T>
Thereafter, the toner T was prepared in the same manner as in “Production of toner K” except that the amount of H2000 silica as an external additive was changed to 1.41 g and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of the toner T obtained here is 5.94 μm, and “number% (Dns) of toner having a particle size of 2.00 μm to 3.56 μm” is The average circularity was 0.938 and the number variation coefficient was 23.8%. Further, the gloss value of the solid image was 32.9, and the toner surface potential on the developing roller was −28V.
Comparative Example 4
<Manufacture of toner mother particles U>
The component of the toner base particle K is 4.4 parts of a colorant dispersion phthalocyanine blue, and the aggregation process (core material aggregation process / shell coating process), circularization process, washing process, and drying of “manufacturing the toner base particle K” In the process, except that the “core material aggregating process”, “shell covering process” and “circularization process” were changed as follows, the toner was prepared in the same manner as in “Production of toner base particles K” in Example 1. Mother particles U were obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.26 μm.

○ Shell coating process
Thereafter, the polymer primary particle dispersion A2 was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed at 250 rpm, and held as it was for 60 minutes.

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / sec at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.940. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Toner U production>
Thereafter, the toner U was changed to 1.41 g as an external additive, and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of toner U obtained here is 5.26 μm, and “number% (Dns) of toner having a particle size of 2.00 μm to 3.56 μm” is The average circularity was 0.940 and the number variation coefficient was 20.8%. Further, the gloss value of the solid image was 32.2, and the toner surface potential on the developing roller was −27V.

Comparative Example 5
<Manufacture of toner mother particles V>
The component of the toner base particle K is 4.4 parts of a colorant dispersion phthalocyanine blue, and the aggregation process (core material aggregation process / shell coating process), circularization process, cleaning process, and drying of “manufacturing the toner base particle K” In the process, except that the “core material aggregating process”, “shell covering process” and “circularization process” were changed as follows, the toner was prepared in the same manner as in “Production of toner base particles K” in Example 1. Base particles V were obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.19 μm.

○ Shell coating process
Thereafter, the polymer primary particle dispersion A2 was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed at 250 rpm, and held as it was for 60 minutes.

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.943. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacturing Toner V>
Thereafter, the toner V was changed by the same external addition process as in “Production of Toner K” except that the amount of H2000 silica as an external additive was changed to 1.41 g and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of the toner V obtained here is 5.19 μm, and “the number% (Dns) of toner having a particle size of 2.00 μm to 3.56 μm” is The average circularity was 0.943 and the number variation coefficient was 20.3%. Further, the gloss value of the solid image was 32.7, and the toner surface potential on the developing roller was −26V.

Comparative Example 6
<Manufacture of toner mother particles W>
The component of the toner base particle K is 4.4 parts of a colorant dispersion phthalocyanine blue, and the aggregation process (core material aggregation process / shell coating process), circularization process, cleaning process, and drying of “manufacturing the toner base particle K” In the process, except that the “core material aggregating process”, “shell covering process” and “circularization process” were changed as follows, the toner was prepared in the same manner as in “Production of toner base particles K” in Example 1. Base particles W were obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.31 μm.

○ Shell coating process
Thereafter, the polymer primary particle dispersion A2 was added over 3 minutes while maintaining the internal temperature at 55.0 ° C. and the rotation speed at 250 rpm, and held as it was for 60 minutes.

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / sec at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.940. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Toner W production>
Thereafter, the toner W was prepared by the same external addition process as in “Production of Toner K” except that the amount of H2000 silica as an external additive was changed to 1.41 g and the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of the toner W obtained here is 5.31 μm, and “the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm” is The average circularity was 0.940 and the number variation coefficient was 19.5%. Further, the gloss value of the solid image was 32.2, and the toner surface potential on the developing roller was −29V.

Comparative Example 7
<Manufacture of toner mother particle X>
The component of the toner base particle K is 9.0 parts of the colorant dispersion quinacridone, and the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing the toner base particle K” 1 except that the “core material agglomeration step”, “shell coating step” and “circularization step” were changed as described below in the same manner as in “Production of toner mother particles K” in Example 1. Particle X was obtained.

○ Core material aggregation process
Polymer primary particle dispersion A1 and 20% in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirring device (double helical blade), heating / cooling device, concentrating device, and each raw material / auxiliary charging device A DBS aqueous solution was charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and continuing stirring at 250 rpm, 0.52 part of 5 mass% aqueous solution of ferrous sulfate was added as FeSO ₄ · 7H ₂ O over 5 minutes, and then the colorant The dispersion was added over 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes with the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 55.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 6.56 μm.

○ Shell coating process
Thereafter, with an internal temperature of 55.0 ° C. and a rotational speed of 250 rpm, a liquid in which 1.0 part of the polymer primary particle dispersion A2 and the charge control agent dispersion β was mixed was added over 3 minutes and held for 60 minutes. .

○ Circularization process
Subsequently, the rotational speed was reduced to 150 rpm (a peripheral speed of 1.56 m / second at the tip of the stirring blade, a stirring speed reduced by 40% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (6 parts as solid content) was added. The mixture was added over 10 minutes, then heated to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.945. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Toner X production>
Thereafter, the toner X was changed to 1.41 g as an external additive, and the toner X was prepared by the same external addition process as in “Production of toner K”, except that the amount of SMT150IB titania fine powder was changed to 0.56 g. Got.

○ Analysis process
The volume median diameter (Dv50) measured using a multisizer of toner X obtained here is 6.56 μm, and “number% (Dns) of toner having a particle size of 2.00 μm to 3.56 μm” is The average circularity was 0.945 and the number variation coefficient was 24.4%. The gloss value of the solid image was 32.5, and the toner surface potential on the developing roller was −29V.

The above results are summarized in Table 1.

According to the table, it can be seen that the gloss of the comparative example is higher than that of the example. In addition, according to the present invention, the charge amount is high, and dirt and afterimages do not occur.
FIG. 2 is a diagram of the image forming apparatus used in the present invention. Among image transfer methods, the tandem method is more likely to cause color misregistration compared to four cycles. Further, in the tandem direct transfer system, contact between the photosensitive drum and the paper occurs, so that fine irregularities are likely to occur on the surface of the photosensitive drum, and toner fine powder easily fits into the irregularities, so that the image is easily affected. In such an image forming apparatus, that is, an image forming apparatus adopting a tandem belt conveying system, the present invention is particularly effective.

  On the other hand, the direct transfer method has excellent image reproducibility because the number of times of transfer is small. In an image forming apparatus that can provide such high image quality, the present invention is particularly effective.

  The toner of the present invention is less likely to cause stains, afterimages (ghosts), blurring (solid followability), etc. on the white background of the image, has good cleaning properties, and has a sharp charge amount distribution, and thus has excellent image stability. The particle size distribution is narrow, and even if the toner particle size is reduced, the amount of fine powder is small, so the bulk density is improved and the fixability is good. It is widely used in image forming methods by high resolution, long life, and high speed printing that have been made.

FIG. 2 is a schematic diagram illustrating an example of a non-magnetic one-component toner developing device using the toner of the present invention. 1 is a schematic diagram illustrating an example of an image forming apparatus that employs a tandem method, a belt conveyance method, and a direct transfer method using toner of the present invention.

Explanation of symbols

1 Electrostatic latent image carrier
2 Toner conveying member
3 Elastic blade (toner layer thickness regulating member)
4 Sponge roller (toner replenishment auxiliary member)
5 Stirring blade
6 Toner
7 Toner Hopper
8 Conveyor belt 9 Pressure roller 10 Laser 11 Toner cartridge 12 Fixing belt
13 Heat source

Claims (19)

A color toner for developing electrostatic images characterized by satisfying all of the following (1) to (4).
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.5 μm or less.
(2) The average circularity is 0.93 or more.
(3) The relationship between the volume median diameter (Dv50) of the color toner and the number% (Dns) of the color toner having a particle diameter of 2.00 μm or more and 3.56 μm or less satisfies Dns ≦ 0.233EXP (17.3 / Dv50). Fulfill.
(4) The number variation coefficient is 24.0% or less.   The relationship between the volume median diameter (Dv50) of the color toner and the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.11EXP (19.9 / Dv50). The color toner for developing an electrostatic image according to claim 1, wherein   The relationship between the volume median diameter (Dv50) of the color toner and the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm satisfies 0.0517EXP (22.4 / Dv50) ≦ Dns. The color toner for developing an electrostatic charge image according to claim 1 or 2.   The color toner for developing an electrostatic charge image according to any one of claims 1 to 3, wherein the volume median diameter (Dv50) of the color toner is 5.0 µm or more.   5. The electrostatic charge image developing color according to claim 1, wherein the number% (Dns) of the color toner having a particle size of 2.00 μm to 3.56 μm is 6% by number or less. toner.   6. The color toner for developing an electrostatic image according to claim 1, wherein the color toner is obtained by forming particles in an aqueous medium.   The color toner for developing an electrostatic charge image according to any one of claims 1 to 6, wherein the color toner is produced by an emulsion polymerization aggregation method.   The color toner for developing an electrostatic charge image according to any one of claims 1 to 7, wherein the color toner is obtained by fixing or adhering resin fine particles to core particles.   The color toner for developing an electrostatic charge image according to any one of claims 1 to 8, wherein the color toner is a magenta toner.   The core particles are composed of at least polymer primary particles, and the ratio of the total amount of polar monomers in 100% by mass of all polymerizable monomers constituting the binder resin as the resin fine particles constitutes the core particles. The color for electrostatic charge image development according to claim 8 or 9, wherein the color is smaller than the ratio of the total amount of polar monomers in 100% by mass of all polymerizable monomers constituting the binder resin as the polymer primary particles. toner.   11. The color toner for developing an electrostatic image according to claim 1, wherein the wax is contained in an amount of 4 to 20 parts by weight with respect to 100 parts by weight of the toner for developing an electrostatic image.   12. The color toner for developing an electrostatic charge image according to claim 1, wherein the color toner is used for an image forming apparatus having a developing process speed of 100 mm / second or more on the latent image carrier. The color toner for developing an electrostatic charge image according to claim 1, wherein the color toner is used for an image forming apparatus satisfying the following formula (5).
(5) Guaranteed lifetime number of sheets (sheets) x printing rate ≧ 400 (sheets) of the developer filled with developer   14. The color toner for developing an electrostatic image according to claim 1, wherein the color toner is used in an image forming apparatus having a resolution of 600 dpi or more on the latent image carrier.   The color for electrostatic image development according to any one of claims 1 to 14, wherein the color is obtained without going through a step of removing particles having a volume median diameter (Dv50) or less of the toner. toner.   The color toner for developing an electrostatic charge image according to any one of claims 1 to 15, wherein the surface potential of the color toner is -30 V or less.   The color toner for developing an electrostatic charge image according to any one of claims 1 to 16, wherein the gloss value of the solid print image of the color toner is 32 or less. An image forming apparatus using a color toner satisfying all of the following (1) to (4).
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.5 μm or less.
(2) The average circularity is 0.93 or more.
(3) The relationship between the volume median diameter (Dv50) of toner and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50).
(4) The number variation coefficient is 24.0% or less. A toner cartridge using a color toner satisfying all of the following (1) to (4):
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.5 μm or less.
(2) The average circularity is 0.93 or more.
(3) The relationship between the volume median diameter (Dv50) of toner and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50).
(4) The number variation coefficient is 24.0% or less.

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