JP2009104123A - Image-forming apparatus and cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image-forming apparatus and a cartridge which inhibit a white-background fouling, afterimage, scattering, streaks, blurring and blind spots attributable to toner particle size distribution or toner/photoreceptor matching, are satisfactory with respect to image quality, thin-line reproducibility and cleanability, can prevent fouling and selective development in long-term use even when applied to a high-speed printer, and can stably form high-resolution images. <P>SOLUTION: In the image-forming apparatus, a photosensitive layer of an electrophotographic photoreceptor contains an oxytitanium phthalocyanine having major diffraction peaks for a CuKα line at Bragg angles (2θ) of 9.0° and 27.2° and having at least one major diffraction peak for the line in the range of 9.3-9.8°, and a toner employed satisfies all of the following requirements: (1) the volume median diameter (Dv50) is 4.0-7.0 μm; (2) the average roundness is ≥0.93; and (3) the volume median diameter (Dv50) and the percentage by number of toner particles having a size of 2.00-3.56 μm (Dns) satisfy the relationship Dns≤0.233EXP(17.3/Dv50). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus and a cartridge used for a copying machine, a printer, 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 amount of particles having a particle size of 3.56 μm or less exceeding the upper limit of the right side in the expression (3) of the present invention, and the meaning is that Is a toner in which a relatively large amount of fine powder remains with respect to 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.

  In addition, the preparation of an electrophotographic photosensitive member having a good matching with a toner having a controlled particle size has been one of important issues.

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 JP 2001-175024 A JP-A-2-000877 JP 2004-045948 A

  Furthermore, in recent years, life extension 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 initial stage of copying, but the density gradually decreases as the copying continues, and the toner particle size increases, resulting in a rough image. Such a phenomenon is said to be inferior in selective developability. Furthermore, 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 high transfer characteristics refers to toner having high transfer efficiency of toner particles developed on the photoreceptor to the intermediate transfer drum or paper, or high transfer efficiency 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 with high transfer characteristics.

Japanese Patent Laid-Open No. 7-098521 JP 2006-091175 A JP 2006-119616 A

  The present invention has been made in view of the above-described background art, and its problems are unevenness in the toner particle size distribution, contamination of the white background of the image due to good or bad matching between the toner and the photoreceptor, an afterimage (ghost), While suppressing scattering, streaks and blurring (solid followability) in the device, the image quality can be improved, the cleaning property is good, the dot missing does not occur to a thin density, the fine line reproducibility is good, and the high-speed printing machine An object of the present invention is to provide an image forming apparatus and a cartridge which are improved in problems such as dirt during long-term use and excellent in image stability even when used. It is another object of the present invention to provide an image forming apparatus and a cartridge capable of preventing “selective development” and stably forming a high resolution image.

  As a result of intensive studies to solve the above problems, the present inventor has found that the above problems can be solved when a specific relational expression is satisfied with respect to the toner particle diameter and a specific electrophotographic photosensitive member is used. The present invention has been completed.

That is, the present invention is an image forming apparatus comprising an electrophotographic photosensitive member having a photosensitive layer on a conductive support, and an electrostatic charge image developing toner, wherein the photosensitive layer of the electrophotographic photosensitive member is at least CuKα. Bragg angles (2θ ± 0.2 °) with respect to characteristic X-rays (wavelength 1.541 mm) have main diffraction peaks at 9.0 ° and 27.2 °, and in the range of 9.3 ° to 9.8 ° Image forming apparatus and cartridge comprising oxytitanium phthalocyanine having at least one main diffraction peak and satisfying all of the following (1) to (3): Is to provide.
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.0 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 size of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50).

  Further, according to the present invention, the photosensitive layer of the electrophotographic photosensitive member has a dipole moment Pcal obtained by structure optimization calculation using semi-empirical molecular orbital calculation using AM1 parameter of 0.2 (D) <P. <2.1 (D) An organic charge transport material satisfying (D) is contained, and the image forming apparatus and the cartridge are provided.

  According to the present invention, since the matching between the toner and the photosensitive member is good, the occurrence of contamination on the white background of the image, scattering in the apparatus, afterimage (ghost), streaks, blurring (solid followability), etc. is suppressed, and long-term use is achieved. Even in such a case, it is possible to supply an image forming apparatus and a cartridge which are less likely to cause the above problem and have excellent image stability. Further, it is possible to supply an image forming apparatus and a cartridge in which dot missing does not occur to a low density and fine line reproducibility is good.

  In addition, even during image formation by the high-speed printing method that has been developed in recent years, the toner particle density distribution is narrow, and even if the toner particle diameter is reduced, the amount of fine powder is small, so the toner powder filling rate, that is, the bulk density is improved. To do. As a result, the air content 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. In addition, it is possible to supply an image forming apparatus and a cartridge which are free from contamination even after long-term use and have excellent image stability.

  Furthermore, it is possible to supply an image forming apparatus and a cartridge in which image defects such as fogging, color spots, and leakage are reduced by the synergistic effect of the toner and the electrophotographic photosensitive member having a photosensitive layer containing a specific substance. .

  In addition, the “selective development” can be prevented, a high-resolution image can be stably provided even in long-term printing, the transfer characteristics are excellent, and in-machine contamination can be prevented.

  Hereinafter, the present invention will be described. However, the present invention is not limited to the following specific embodiments, and can be arbitrarily modified without departing from the spirit of the present invention.

The electrostatic image developing toner of the present invention (hereinafter sometimes abbreviated as “toner”) satisfies all of the following (1) to (3).
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.0 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 size of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50).

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

  The Dv50 of the toner in the present invention is 4.0 μm or more and 7.0 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 remarkably exerted by being 6.8 μm or less, more preferably 6.5 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 more preferable that it is 5.0 micrometers or more, It is especially preferable that it is 5.3 micrometers or more.

Regarding (2) The average circularity of the toner is measured by the method described in the examples, and is defined as that measured. The average circularity of the toner in the present invention is 0.93 or more, preferably 0.94 or more. In general, toner with high circularity has good transfer efficiency. Since the spherical toner having a high degree of circularity is less likely to get caught between toners or various members, the mechanical share at the charging roller is small, and the surface shape change 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. Further, since it is excellent in releasability from the photosensitive drum, the transfer efficiency is excellent, it is possible to secure a sufficient image density and to reduce the residual toner.

  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 with the cleaning blade, the cleaning blade is easily slipped through, which causes the image to become dirty. In the case of high-speed printing, this phenomenon becomes more remarkable. Therefore, the average circularity of the toner in the present invention is preferably 0.97 or less, more preferably 0.96 or less. Furthermore, toner having a small particle size and high circularity is difficult to scrape off with a cleaning blade, and the toner easily passes through the cleaning blade. Therefore, it is particularly necessary to control the particle size distribution according to the circularity. is there.

Regarding (3) The number% (Dns) of toner having a toner particle size 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. The toner in the present invention has a 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.
Dns ≦ 0.233EXP (17.3 / Dv50)
Meet. In the present invention, “EXP” indicates “Exponential”. That is, the base of the natural logarithm, and the right side is the exponent. This expression is sometimes referred to as “requirement (3) expression”.

  The purpose of this relational expression (the expression of requirement (3)) indicates that the amount of fine powder increases as the volume median diameter (Dv) of the toner decreases, and the region where Dv is 4.5 μm or less. Then, the value of Dns increases exponentially because the value of Dv approaches a region having a particle size of 2.00 μm or more and 3.56 μm or less. 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, particles included in the particle diameter range of 2.00 μm to 3.56 μm are particle size regions that should be specifically excluded in the region of the volume median diameter of toner particles of 4.0 to 7.0 μm. The basis for this follows experimental results.

  The toner according to the present invention having a particle size distribution satisfying the above requirement (3) provides high image quality, and is less contaminated even when a high-speed printing machine is used, resulting in an afterimage (ghost) or blur (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, The above-mentioned “selective development” is unlikely to occur because particles having a large charge amount do not develop and adhere to members such as a layer regulating blade and a roller to cause image defects such as streaks and blurring.

  That is, the fine powder amount affects the image with the above requirement (3) as a boundary. When the value of Dns exceeds the right side, the fine powder causes a defect in the image. For example, as shown in FIG. 4, fine powder may accumulate on the cleaning blade, and afterimages, blurring, dirt, and the like may occur as image defects.

  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. Particles exceeding the specific charge amount may adhere to the member or the like and become contaminated or fluidity may be deteriorated. On the other hand, particles that do not satisfy the specific charge amount may 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. When the toner of the present invention is used, the “selective development” described above is suppressed. 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.

  In addition, the reason why the particle size% (Dns) is specified to be 2.00 μm or more and 3.56 μm or less is the lower limit value, which is the measurement limit of the apparatus used for measuring the toner particle size in the present invention. Yes, the upper limit is the critical value of the effect obtained from the results described in the examples. That is, when the number% of the toner having a particle size larger than 3.56 μm is employed, the toner that exhibits the effect of the present invention and the toner that does not exhibit the effect cannot be clearly distinguished by a formula.

Also, the relationship between Dv50 and Dns is
(3-1) Dns ≦ 0.110EXP (19.9 / Dv50)
A toner satisfying this requirement is preferable from the viewpoint of the above effects.
On the other hand, from the viewpoint of producing with good yield, the relationship between Dv50 and Dns is
(3-2) 0.0517EXP (22.4 / Dv50) ≦ Dns
It is preferable to satisfy.

  Further, a toner having a Dns of 6% by number or less is preferable in that it provides a higher quality image and hardly contaminates the image forming apparatus. Further, it is more preferable that the above-mentioned preferable particle diameter range of Dv50, for example, the condition that “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, a toner that hardly contaminates the image forming apparatus and does not easily cause “selective development”, without reducing the yield from the viewpoint of production.

  The toner provided in the image forming apparatus of the present invention must satisfy all of the above (1) to (3). Conventional toners do not satisfy any of (1) to (3). The reason is that if the amount of fine powder is reduced as much as possible (when (3) is satisfied), coarse powder is generated, the number variation coefficient increases, and the toner tends to be undesirable. In addition, if the toner is made circular by physical impact (when (2) is satisfied), it may cause the generation of fine powder (not satisfy (3)), or thermal If the toner is to be circularized by fusing (if (2) is satisfied), the particles will be fused to generate coarse powder, and the number variation coefficient will increase.

  The toner satisfying all the requirements (1), (2) and (3) in the present invention can obtain high image quality, and has little stains even when a high-speed printing machine is used, and afterimage (ghost) and blur (solid) (Trackability) is suppressed, and the cleaning property is excellent. 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 adhere to a member such as a layer regulating blade or a roller and cause image defects such as streaks and blurring. That is, the “selective development” described above is unlikely to occur.

  The toner provided in the image forming apparatus of the present invention must satisfy all the requirements (1), (2), and (3), but the number variation coefficient is preferably 24.0% or less. . More preferably, it is 22.0% or less, Especially preferably, it is 20.0% or less, More preferably, it is 19.0% or less. Generally, when the value of the number variation coefficient is high, the distribution of the charge amount becomes broad, and an image defect may be caused due to poor charging. Further, contamination due to adhesion to the toner member or the like, and contamination due to scattering may be induced. Therefore, the number variation coefficient is preferably low. On the other hand, from the industrial viewpoint, the number variation coefficient is preferably greater than 0%, more preferably 5% or more. The number variation coefficient (%) is measured by the method described in the examples and is defined as that measured.

  The 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 blurring due to fusion.

  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. In the apparatus, image defects such as scattering and streaking and blurring are caused, and 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.

  One of the numerical values indicating the “charge amount distribution” of the toner in the present invention “standard deviation of charge amount” is preferably 1.0 to 2.0, more preferably 1.0 to 1.8. More preferably, it is 1.0 to 1.5. When the above upper limit is exceeded, toner adheres to the layer regulation blade and is difficult to be transported, and the adhered toner further blocks the transported toner and contaminates members in the image forming apparatus. There may not be. Moreover, when it falls below the lower limit, it may not be preferable from an industrial viewpoint. About a lower limit, it is preferable that it is 1.3 or more.

  Since the toner in the present invention has a sharp charge amount distribution, there is very little contamination (toner scattering) in the image forming apparatus caused by poorly charged toner. 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 toner of the present invention has a sharp charge amount distribution, so the developability is very good, and there are very few toner particles that accumulate without being developed. The effect is exhibited in the apparatus. Specifically, a toner used in an image forming apparatus that satisfies the following formula (G) is preferable in order to sufficiently exhibit the above-described effects of the present invention.
(G) Guaranteed lifetime number of sheets (sheets) x printing rate ≧ 400 (sheets) of the developer filled with developer
In the formula (G), the “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 toner in the present invention has a very sharp particle size distribution, the reproducibility of the latent image 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 cartridge of the present invention are characterized by using a toner that satisfies all of the above (1) to (3). By using such a toner, the resolution to the electrostatic latent image carrier can be improved. Can provide a high-resolution image having a resolution of 600 dpi or more. “Resolution to electrostatic latent image carrier” is the same as “resolution of device”.

<Configuration of toner>
The toner used in the image forming apparatus and cartridge of the present invention is configured by appropriately selecting a binder resin, a colorant, a wax, an external additive, and the like. The binder resin may be appropriately selected from those known to be used 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 toner in the present invention may be appropriately selected from those known to be usable for toner. For example, yellow pigments, magenta pigments, and cyan pigments shown below can be used. As black pigments, carbon black or a mixture of the following yellow pigments / magenta pigments / cyan pigments toned to black is used. .

  Among these, carbon black as a black pigment exists as an aggregate of very fine primary particles, and when dispersed as a pigment dispersion, coarsening of particles due to reaggregation tends to occur. The degree of reagglomeration of carbon black particles correlates with the amount of impurities contained in carbon black (the degree of residual undecomposed organic matter). If there are many impurities, coarsening due to reaggregation after dispersion tends to be severe. showed that. As a quantitative evaluation of the amount of impurities, the ultraviolet absorbance of the toluene extract of carbon black measured by the following method is preferably 0.05 or less, and more preferably 0.03 or less. Generally, carbon black produced by the channel method tends to have a large amount of impurities, and therefore, carbon black produced by the furnace method is preferred as the carbon black in the present invention.

  The ultraviolet absorbance (λc) of carbon black is determined by the following method. First, 3 g of carbon black was sufficiently dispersed and mixed in 30 mL of toluene. Filter using 5C filter paper. Thereafter, the filtrate was put in a quartz cell having a 1 cm square light absorption part, and the value (λs) measured for absorbance at a wavelength of 336 nm using a commercially available ultraviolet spectrophotometer, and the value obtained by measuring the absorbance of toluene alone as a reference using the same method. From (λo), the ultraviolet absorbance is obtained by λc = λs−λo. Examples of commercially available spectrophotometers include an ultraviolet-visible spectrophotometer (UV-3100PC) manufactured by Shimadzu Corporation.

  As yellow pigments, compounds typified by condensed azo compounds, isoindolinone compounds and the like are used. 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, 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.

  The toner in the present invention is preferably blended with a wax for imparting 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 soy castor oil and carnauba wax; ketones having long chain alkyl groups such as distearyl ketone; silicones having alkyl groups; 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 size, 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 in 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 toner in 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. 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 toner in the present invention is not particularly limited. That is, it can be produced by a pulverization method or a method of forming particles in an aqueous medium (hereinafter sometimes abbreviated as “wet method”). As the wet method, a method of performing radical polymerization in an aqueous medium such as a suspension polymerization method or an emulsion polymerization aggregation method (hereinafter abbreviated as “polymerization method”, and the obtained toner may be abbreviated as “polymerization toner”). And a chemical pulverization method typified by a melt suspension method 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.

  When a toner is manufactured by a pulverization method, fine particles are generally easily generated, so that a classification step is necessary. In particular, an excessive classification operation may be required in order to satisfy the toner particle size requirement in the present invention, and the yield is remarkably reduced. Such an operation is not preferable from an industrial point of view. The pulverized toner is not excluded as the toner used in the image forming apparatus. On the other hand, the toner in the present invention is preferably obtained by a wet method in which particles are formed in an aqueous medium, from the viewpoint that a classification step that does not easily generate fine powder is not essential.

  As a method for obtaining a toner having a specific particle size distribution in the present invention, any of a polymerization method such as a pulverization method, a suspension polymerization method, an emulsion polymerization aggregation method, a chemical pulverization method represented by a melt suspension method, etc. Manufacturing methods can also be used. However, in the “pulverization method”, “suspension polymerization method” and “chemical pulverization method represented by the melt suspension method”, all of them are larger than the particle diameter of the toner. In order to adjust to a small size, if it is attempted to reduce the average particle size, the particle size ratio on the small particle side tends to increase, and an excessive burden is imposed in the classification step and the like. In contrast, the emulsion polymerization agglomeration method has a relatively sharp particle size distribution and is adjusted from a smaller size to a larger size than the toner base particle size, so that the particle size can be adjusted without going through a classification step or the like. A toner having a distribution is obtained. Therefore, it is particularly preferable to produce the toner in the present invention by the emulsion polymerization aggregation method for the above reasons.

  The following is 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 explain. 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- dibutyl acrylamide, acrylic acid amide and the like. 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 the 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 with respect to 100 parts by weight of the polymerizable monomer. Among them, it is preferable that at least 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 can be used as necessary. Specific examples of such a chain transfer agent include t-dodecyl mercaptan, 2-mercaptoethanol, diisopropylxanthogen, 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, and 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 a 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 JIS K0070.

  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, the particle diameter, particle shape, and particle size distribution of the core particles can be easily adjusted to an arbitrary 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 fusing (preferably after a shell coating step for fixing or adhering resin fine particles or the like), and washing and drying the obtained particles.

  The colorant is not particularly limited as long as it is a commonly used colorant. Examples thereof include the pigments described above, carbon black such as furnace black and lamp black, and magnetic colorants. 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 in the toner, more preferably 1 to 15 parts by weight, particularly preferably 3 to 12 parts by weight.

The colorant may have magnetism, and examples of the magnetic colorant include a ferromagnetic material that exhibits ferrimagnetism or ferromagnetism in the vicinity of 0 to 60 ° C., which is a use environment temperature of a printer, a copying machine, and the like. Is, for example, magnetite (Fe ₃ O ₄ ), maghemite (γ-Fe ₂ O ₃ ), an intermediate or mixture of magnetite and maghemite, M _x Fe _3-x O ₄ , where M is Mg, Spinel ferrite such as Mn, Fe, Co, Ni, Cu, Zn, Cd, hexagonal ferrite such as BaO.6Fe ₂ O ₃ , SrO.6Fe ₂ O ₃ , Y ₃ Fe ₅ O ₁₂ , Sm ₃ Fe ₅ O garnet-type oxides such as _12, shown rutile oxides such as CrO _2, and, Cr, Mn, Fe, Co, the magnetic near 0 to 60 ° C. of such metal or their ferromagnetic alloys such as Ni Ones, and among them, magnetite, maghemite, or magnetite and maghemite intermediates are preferred.

  When it is contained from the viewpoint of scattering prevention, charge control, etc. while having the characteristics as a non-magnetic toner, the content of the magnetic powder in the toner is 0.2 to 10% by mass, preferably 0.5 to 0.5%. It is 8 mass%, More preferably, it is 1-5 mass%. When used as a magnetic toner, the content of the magnetic powder in the toner is usually 15% by mass or more, preferably 20% by mass or more, and usually 70% by mass or less, preferably 60% by mass or less. It is desirable. If the content of the magnetic powder is less than the above range, the magnetic force required for the magnetic toner may not be obtained, and if it exceeds the above range, it may cause poor fixing properties.

  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.

  It is preferable to contain a wax for improving the fixing property. 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 heat is applied, 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.

  In the toner used in the present invention, a charge control agent may be blended 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. Of these, the charge control agent is preferably emulsified and dispersed in water using an emulsifier, and used as an emulsified dispersion having a volume average diameter (Mv) of 0.01 μm to 3 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 a temperature range of (Tg-20 ° C) to Tg of the polymer primary particles, and a range of (Tg-10 ° C) to (Tg-5 ° C). It is preferable that

  In addition, as a method for preventing sudden agglomeration in order to prevent 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 The time from a temperature 8 ° C. lower than the temperature at the time of operation for stopping the growth of core particles by addition, pH control, etc. (hereinafter sometimes abbreviated as “aggregation final temperature”) to the aggregation final temperature is 30 minutes or more. Preferably, it is more preferably 1 hour or longer. 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 order to obtain a toner that satisfies all of the above requirements (1) to (3), it is preferable to employ an operation in which the aggregation speed is not high compared to the operation that is normally performed in the aggregation process. 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 operations in which the agglomerated particles are difficult to finely disperse include, for example, a method of lowering the number of revolutions for stirring, a method of adding a dispersion stabilizer continuously or intermittently, and a method of previously mixing a dispersion stabilizer and water. . The toner satisfying all of the above requirements (1) to (3) is obtained by converting the finally obtained toner or toner base particles into particles having a volume median diameter (Dv50) or less by operations such as classification. It is preferable to be obtained without going through the removing step.

  In the present invention, the toner primary particles are obtained by washing and drying the particles obtained by agglomerating the polymer primary particles to form core particles, followed by a shell coating step for fixing or adhering resin fine particles, and then fusing. It is preferable to obtain.

  The ratio of the resin fine particles to the whole core particles is preferably 0.5 to 30 parts by weight, particularly preferably 5 to 20 parts by weight with respect to 100 parts by weight of the core particles.

  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 occupies in 100% by mass of the total polymerizable monomer 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.

  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 the “step of starting the temperature rise after the addition of the emulsifier” is adopted, that is, when the maturation step is performed after the cohesive force is sharply reduced, the resin fine particles once adhered due to the rapid decrease of the cohesive force May become easier to leave. 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 blending amount in the case of blending the emulsifier is not limited, but is preferably 0.1 parts by weight or more, more preferably 1 part by weight or more, 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 by 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 of the small particle toner used in the image forming apparatus of the present invention is sharp, before the step of adding an emulsifier or a pH adjuster. There is a method of reducing the stirring rotation speed, that is, reducing 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, a toner having a specific particle size distribution used in the image forming apparatus of the present invention, that is, a toner satisfying all the requirements (1) to (3) can be obtained by the above method. The content of the fine particles can be adjusted by the degree to which the rotational speed is reduced. For example, when the stirring rotation speed is decreased from 250 rpm to 150 rpm, a toner having a small particle size with a sharper particle size distribution than that of a known toner can be provided, and the toner having a specific particle size distribution used in the image forming apparatus 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 the stirring vessel (c) Peripheral speed at the tip of the stirring blade (d) Shape of the stirring blade (e) Vary depending on conditions such as the position of the blade in the stirring vessel. 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, resin fine particles mainly composed of a polymer are further formed on the surface of the particles obtained by the emulsion polymerization aggregation method by a method such as a spray drying method, an in-situ method, or a submerged particle coating method. Is formed as an outer layer, preferably in a thickness of 0.01 to 0.5 μm, whereby encapsulated toner base particles can be obtained.

  By devising the manufacturing method as described above, toner base particles that can satisfy all of the requirements (1) to (3) can be manufactured. Then, by the external addition process described later, (1) to (3) A toner that satisfies all the requirements can be obtained.

  In addition, in the emulsion polymerization aggregation method toner, the average circularity measured using a flow type particle image analyzer FPIA-2100 is 0.93 or more, and particularly preferably 0.94 or more. 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 gel permeation chromatography (hereinafter sometimes abbreviated as “GPC”) of a soluble content of the toner with respect to tetrahydrofuran (hereinafter also abbreviated as “THF” where appropriate) is preferable. Is 30,000 or more, more preferably 40,000 or more, further preferably 50,000 or more, preferably 200,000 or less, more preferably 150,000 or less, 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 the charge control agent, selection and blending amount of the external additive, and the like.

<Pulverized toner>
The method for producing a pulverized toner having a particle size distribution in a specific range used in the image forming apparatus of the present invention is not particularly limited, and examples thereof include an excessive classification method.

  The resin used for producing the pulverized toner 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, ionomer resin, polyurethane resin, silicone resin, ketone resin, ethylene-acrylate copolymer, xylene Resin, polyvinyl butyral resin, etc. are used. These resins can be used alone or in combination.

  The polyester resin is composed of a polyhydric alcohol and a polybasic acid, and if necessary, a polymerizable monomer composition containing at least one of these polyhydric alcohol and polybasic acid containing a trifunctional or higher polyfunctional component (crosslinking component) Obtained by polymerization. In the above, examples of the divalent alcohol used for the synthesis of the polyester resin include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, and neopentyl. Diols such as glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, bisphenol A, hydrogenated bisphenol A, polyoxyethylenated bisphenol A, polyoxypropylenated bisphenol A, etc. Bisphenol A alkylene oxide adducts and others can be mentioned. Among these monomers, it is particularly preferable to use a bisphenol A alkylene oxide adduct as the main component monomer, and among them, an adduct having an average addition number of alkylene oxide of 2 to 7 per molecule is preferable.

  Examples of trihydric or higher polyhydric alcohols involved in the crosslinking of polyester include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, and sucrose. 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1, Mention may be made of 3,5-trihydroxymethylbenzene and others.

  On the other hand, examples of the polybasic acid include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malon. Examples thereof include acids, anhydrides of these acids, lower alkyl esters, alkenyl succinic acids such as n-dodecenyl succinic acid and n-dodecyl succinic acid, alkyl succinic acids, and other divalent organic acids.

  Examples of the tribasic or higher polybasic acid involved in the crosslinking of polyester include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 2, 5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, tetra (methylenecarboxyl) Mention may be made of methane, 1,2,7,8-octanetetracarboxylic acid and anhydrides thereof.

  These polyester resins can be synthesized by a usual method. Specifically, conditions such as reaction temperature (170 to 250 ° C.), reaction pressure (5 mmHg to normal pressure) and the like are determined according to the reactivity of the monomer, and the reaction is terminated when predetermined physical properties are obtained. . The Sp of the polyester resin according to the present invention is preferably 90 to 135 ° C, and more preferably 95 to 133 ° C among them. The range of Tg is, for example, 50 to 65 ° C. when the softening point is 90 ° C., and 60 to 75 ° C. when the softening point is 135 ° C. In this case, when Sp is lower than the above range, an offset phenomenon at the time of fixing is likely to occur. When Sp is higher than the above range, the fixing energy increases, and color toner tends to deteriorate glossiness and transparency. . Further, when Tg is lower than the above range, toner agglomerates and fixation are likely to occur, and when Tg is higher than the above range, the fixing strength at the time of thermal fixing tends to be low, such being undesirable. Sp can be adjusted mainly by the molecular weight of the resin. When the tetrahydrofuran soluble content of the resin is measured by the GPC method, the number average molecular weight is preferably 2000 to 20000, and more preferably 3000 to 12000. Further, Tg can be adjusted mainly by selecting a monomer component constituting the resin. Specifically, Tg can be increased by using an aromatic polybasic acid as a main component as an acid component. That is, among the polybasic acids described above, phthalic acid, isophthalic acid, terephthalic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, and the like, anhydrides thereof, lower alkyl esters, etc. It is desirable to use it as a main component.

In the present invention, Sp is defined as a value measured using a flow tester described in JIS K7210 and K6719. Specifically, using a flow tester (CFT-500, manufactured by Shimadzu Corporation), a plunger having an area of 1 cm ² while heating a sample of about 1 g at a preheating time of 50 ° C. for 5 minutes and a heating rate of 3 ° C./min. A load of 30 kg / cm ² is applied by pushing through a die having a hole diameter of 1 mm and a length of 10 mm. Thus, a plunger stroke-temperature curve is drawn, and when the height of the S-shaped curve is h, the temperature corresponding to h / 2 is defined as the softening point. Moreover, the measurement of Tg is defined as what was measured in accordance with the conventional method using the differential scanning calorimeter (DSC7 by Perkin-Elmer company, or DSC120 by Seiko Electronics Co., Ltd.).

  In general, when the acid value of the polyester resin is too high, it is difficult to obtain a stable high charge amount, and the charge stability at high temperature and high humidity tends to deteriorate. Therefore, in the present invention, the acid value is 50 KOHmg / g. It is preferable to adjust to the following, more preferably 30 KOH mg / g or less, and most preferably 3 to 15 KOH mg / g. As a method for adjusting the acid value within the above range, in addition to a method of controlling the blending ratio of alcohol-based and acid-based monomers used at the time of resin synthesis, for example, the acid monomer component is previously converted into a lower alkyl ester by transesterification. Examples include a method of synthesizing using an acid group and a method of neutralizing residual acid groups by blending a basic component such as an amino group-containing glycol in the composition. It goes without saying that can be adopted. In the present invention, the acid value of the polyester resin is measured according to the method of JIS K0070. However, when the resin is difficult to dissolve in the solvent, a good solvent such as dioxane is used.

The polyester resin is represented by the following formulas (a) to (d) when the glass transition temperature (Tg) is plotted as an x-axis variable and the softening point (Sp) is plotted as a y-axis variable on the xy coordinates. Those having physical properties within a range surrounded by a straight line are preferred. The unit of Tg and Sp is “° C.”.
Formula (a) Sp = 4 * Tg-110
Formula (b) Sp = 4 * Tg-170
Formula (c) Sp = 90
Formula (d) Sp = 135

  When the polyester resin having the physical properties surrounded by the straight lines represented by the above formulas (a) to (d) is used for the pulverized toner, the pulverized toner is extremely resistant to mechanical stress and is continuously used. In some cases, the toner can be prevented from aggregating or solidifying due to frictional heat generated, and appropriate chargeability can be maintained over a long period of time.

  The pulverized toner is not particularly limited as long as it is a commonly used colorant. For example, the colorant used for the above-described polymerized toner can be used. The content ratio 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 mass in the same degree as the polymerized toner. More preferably, it is 1-15 mass parts, Most preferably, it is 3-12 mass parts.

  The pulverized toner may contain other constituent materials. For example, all known charge control agents can be used. For example, there are nigrosine dyes, amino group-containing vinyl copolymers, quaternary ammonium salt compounds, polyamine resins and the like for positive chargeability, and those containing metals such as chromium, zinc, iron, cobalt and aluminum for negative chargeability. Metal azo dyes, salts of salicylic acid or alkylsalicylic acid with the aforementioned metals, metal complexes and the like are known. As usage-amount, 0.1-25 mass parts is good with respect to 100 mass parts of resin, More preferably, 1-15 mass parts is good. In this case, the charge control agent may be blended in the resin, or may be used in a form adhered to the surface of the toner base particles.

  Among these charge control agents, taking into account the charge imparting ability for the toner and color toner adaptability (the charge control agent itself is colorless or light color and has no color disturbance to the toner), it is an amino group for positive chargeability. Preferred are vinyl-containing copolymers and / or quaternary ammonium salt compounds. For negative chargeability, metal salts and metal complexes of salicylic acid or alkylsalicylic acid with chromium, zinc, aluminum, boron, etc. are preferred.

  Among these, examples of the amino group-containing vinyl copolymer include copolymer resins of amino acrylates such as N, N-dimethylaminomethyl acrylate and N, N-diethylaminomethyl acrylate and styrene and methyl methacrylate. Examples of the quaternary ammonium salt compound include tetraethylammonium chloride, a salt-forming compound of benzyltributylammonium chloride and naphtholsulfonic acid, and the like. For the positively chargeable toner, the above amino group-containing vinyl copolymer and the quaternary ammonium salt compound may be blended alone or in combination.

  As the metal salt and metal complex of salicylic acid or alkyl salicylic acid, among various known substances, chromium, zinc or boron complex of 3,5-ditertiary butyl salicylic acid is particularly preferable. Further, the above colorant and charge control agent may be subjected to a preliminary dispersion treatment, so-called master batch treatment, by pre-kneading with a resin in advance in order to improve dispersibility and compatibility in the toner.

  In the pulverized toner, any other known component such as a low-melting-point release agent such as low molecular weight polyalkylene, paraffin wax, ester wax or the like can be contained as other constituent components.

Examples of the method for producing a pulverized toner having a specific particle size distribution of the present invention include the following.
1. Resin, charge control substance, colorant and additives added as necessary are uniformly dispersed with a Henschel mixer or the like.
2. The dispersion is melt-kneaded with a kneader, an extruder, a roll mill or the like.
3. The kneaded product is roughly pulverized with a hammer mill, a cutter mill or the like, and then finely pulverized with a jet mill, an I-type mill or the like.
4). The finely pulverized product is classified with a dispersion classifier, a zigzag classifier or the like.
5). An external additive such as silica is dispersed in the classified product with a Henschel mixer or the like.

  In particular, the above 4. The toner for electrostatic image development used in the image forming apparatus of the present invention can be produced by a pulverization method by performing the classification until the specific particle size distribution of the present invention is obtained.

<Suspension polymerization method>
The method for producing a suspension polymerization method toner having a particle size distribution in a specific range of the present invention is not particularly limited. For example, the chemical structure such as the number of polar groups of the binder polymer, the molecular weight distribution, and the suspension state are improved. Adjust the type and amount of additives (dispersion stabilizer, etc.), stirring intensity during suspension polymerization, addition method of polymerizable monomer, type and amount of polymerization initiator and chain transfer agent, polymerization temperature, degree of classification, etc. By doing. Particularly preferable methods include a method in which a high shearing force is applied in a process in which polymerizable monomer droplets are generated, or a dispersion stabilizer or the like is increased.

  Examples of the raw material such as resin used in producing the suspension polymerization toner include those described in the emulsion polymerization aggregation method.

<Chemical grinding method represented by melt suspension method>
A method for producing a toner having a particle size distribution in a specific range of the present invention by a chemical pulverization method typified by a melt suspension method is not particularly limited. For example, the type of binder polymer, chemical structure, molecular weight distribution, etc. The kind and amount of the water additive that makes the suspended state good; the stirring strength at the time of addition of the polymer solution, the addition method, the temperature, etc .; if necessary, the degree of classification is adjusted.

  Examples of the resin used when the toner is manufactured by a chemical pulverization method such as a melt suspension method include those described in the section of the pulverization method. Other materials include those described in the emulsion polymerization aggregation method.

  The toner used in the image forming apparatus of the present invention is for a two-component developer in which a carrier for conveying the toner to the electrostatic latent image portion coexists, or magnetic one-component development in which magnetic powder is contained in the toner. For non-magnetic one-component developers that do not use magnetic powder as a developer, but for non-magnetic one-component development systems in order to achieve the effects of the present invention remarkably The developer is preferably used.

  When used as the 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-based, ferrite-based, or magnetite-based carrier, or a resin coating on the surface thereof. Applied ones or magnetic resin carriers 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.

<Configuration of electrophotographic photoreceptor>
The image forming apparatus and the cartridge of the present invention have an electrophotographic photosensitive member having a specific photosensitive layer on a conductive support.

<Conductive support>
As the conductive support used for the photoreceptor, for example, metal materials such as aluminum, aluminum alloy, stainless steel, copper, nickel, and conductive powders such as metal, carbon, and tin oxide are added to impart conductivity. A resin material, a resin, glass, paper, or the like on which a conductive material such as aluminum, nickel, or ITO (indium tin oxide) is deposited or applied on the surface is mainly used. As a form, a drum shape, a sheet shape, a belt shape or the like is used. A conductive material having an appropriate resistance value may be applied to a conductive support made of a metal material in order to control conductivity, surface properties, etc., or to cover defects.

  When a metal material such as an aluminum alloy is used as the conductive support, it is preferably used after an anodized film is applied. When an anodized film is applied, it is desirable to perform a sealing treatment by a known method.

For example, an anodic oxidation film is formed by anodizing in an acidic bath such as chromic acid, sulfuric acid, oxalic acid, boric acid, sulfamic acid, etc. give. In the case of anodic oxidation in sulfuric acid, the sulfuric acid concentration is 100 to 300 g / L, the dissolved aluminum concentration is 2 to 15 g / L, the liquid temperature is 15 to 30 ° C., the electrolysis voltage is 10 to 20 V, and the current density is 0.5 to it is preferably in the range of 2A / dm ^2, but not limited to the above conditions.

  It is preferable to perform a sealing treatment on the anodic oxide film thus formed. The sealing treatment may be performed by a known method. For example, it is immersed in an aqueous solution containing nickel fluoride as a main component, or immersed in an aqueous solution containing nickel acetate as a main component. A high temperature sealing treatment is preferably performed.

  The concentration of the nickel fluoride aqueous solution used in the case of the low-temperature sealing treatment can be appropriately selected, but more preferable results are obtained when it is used in the range of 3 to 6 g / L. Moreover, in order to advance a sealing process smoothly, as processing temperature, it is 25-40 degreeC, Preferably it is 30-35 degreeC, Moreover, nickel fluoride aqueous solution pH is 4.5-6.5, Preferably it is 5 It is better to process in the range of .5 to 6.0. As the pH adjuster, oxalic acid, boric acid, formic acid, acetic acid, sodium hydroxide, sodium acetate, aqueous ammonia and the like can be used. The treatment time is preferably in the range of 1 to 3 minutes per 1 μm of film thickness. In order to further improve the physical properties of the film, cobalt fluoride, cobalt acetate, nickel sulfate, a surfactant or the like may be added to the nickel fluoride aqueous solution. Subsequently, it is washed with water and dried to finish the low temperature sealing treatment. As the sealing agent in the case of the high-temperature sealing treatment, an aqueous solution of a metal salt such as nickel acetate, cobalt acetate, lead acetate, nickel acetate-cobalt, and barium nitrate can be used, and it is particularly preferable to use nickel acetate. . The concentration in the case of using an aqueous nickel acetate solution is preferably 5 to 20 g / L. The treatment temperature is 80 to 100 ° C., preferably 90 to 98 ° C., and the pH of the nickel acetate aqueous solution is preferably 5.0 to 6.0. Here, ammonia water, sodium acetate, or the like can be used as the pH adjuster. The treatment time is 10 minutes or longer, preferably 20 minutes or longer. In this case as well, sodium acetate, organic carboxylic acid, anionic and nonionic surfactants may be added to the nickel acetate aqueous solution in order to improve the film properties. Subsequently, it is washed with water and dried to finish the high temperature sealing treatment. When the average film thickness is thick, stronger sealing conditions are required due to the higher concentration of the sealing liquid and high temperature / long-time treatment. Accordingly, productivity is deteriorated and surface defects such as spots, dirt, and dusting are likely to occur on the coating surface. From such a point, it is preferable that the average film thickness of the anodic oxide coating is usually 20 μm or less, particularly 7 μm or less.

  The support surface may be smooth, or may be roughened by using a special cutting method or polishing. Further, it may be roughened by mixing particles having an appropriate particle diameter with the material constituting the support. In order to reduce the cost, it is possible to use the drawing tube as it is without cutting. Especially when using non-cutting aluminum supports such as drawing, impact processing, ironing, etc., the process eliminates dirt, foreign matter, etc. on the surface, small scratches, etc., and a uniform and clean support can be obtained. Therefore, it is preferable. Specifically, the conductive support preferably has a surface roughness Ra of 0.01 or more and 0.3 μm or less. If Ra is less than 0.01 μm, the adhesion may be deteriorated, and if it exceeds 0.3 μm, image defects such as black spots tend to occur. The most preferable range of Ra is 0.01 to 0.20 μm.

  In order to process the surface roughness of the conductive support within the above range, a method of grinding the support surface with a cutting tool or the like, or a method of sandblasting by causing fine particles to collide with the support surface There are a processing method using an ice particle cleaning device described in JP-A-4-204538 and a honing processing method described in JP-A-9-236937. Further, an anodizing method, an alumite treatment method, a buffing method, a laser ablation method described in JP-A-4-233546, a method using a polishing tape described in JP-A-8-001502, Examples thereof include a roller burnishing method described in Kaihei 8-001510. However, the method for roughening the surface of the support is not limited thereto.

[Definition and measurement method of surface roughness]
The surface roughness Ra means arithmetic average roughness and represents an average value of absolute value deviations from the average line. Specifically, a reference length is extracted from the roughness curve in the direction of the average line, and the absolute values of deviations from the average line of the extracted portion to the measurement curve are summed and averaged. In Examples described later, the Ra was measured with a surface roughness meter (Tokyo Seimitsu Surfcom 570A). However, other measuring instruments may be used as long as the measuring instrument produces the same result within the error range.

  As the conductive material, a metal drum such as aluminum or nickel, a plastic drum deposited with aluminum, tin oxide, indium oxide or the like, or a paper / plastic drum coated with a conductive substance can be used. The material for the conductive support is preferably a material having a specific resistance of 103 Ωcm or less at room temperature.

<Underlayer>
The photoreceptor used in the image forming apparatus of the present invention preferably contains an undercoat layer. The undercoat layer preferably contains a binder resin and metal oxide particles having a refractive index of 2.0 or less. Further, the volume average particle diameter of the metal oxide aggregate secondary particles in a liquid in which the undercoat layer is dispersed in a solvent in which methanol and 1-propanol are mixed at a weight ratio of 7: 3 is 0.1 μm or less. In addition, the 90% cumulative particle size is preferably 0.3 μm or less. More preferably, the volume average particle size is 0.09 μm or less and the 90% cumulative particle size is 0.2 μm or less. Further, if the volume average diameter is too small, cleaning failure and device contamination may be caused. The volume average particle diameter is preferably 0.01 μm or more, and the cumulative 90% particle diameter is also preferably 0.05 μm or more.

<Metal oxide>
In the present invention, it is preferable to use metal oxide particles for the undercoat layer. As the metal oxide particles, any metal oxide particles that can be generally used for an electrophotographic photoreceptor can be used. More specifically, as metal oxide particles, metal oxide particles containing one kind of metal element such as titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, zinc oxide, iron oxide, calcium titanate, strontium titanate And metal oxide particles containing a plurality of metal elements such as barium titanate. Among these, metal oxide particles having a band gap of 2 to 4 eV are preferable. As the metal oxide particles, only one type of particles may be used, or a plurality of types of particles may be mixed and used. Among these metal oxide particles, titanium oxide, aluminum oxide, silicon oxide, and zinc oxide are preferable, titanium oxide and aluminum oxide are more preferable, and titanium oxide is particularly preferable.

  As the crystal form of the titanium oxide particles, any of rutile, anatase, brookite, and amorphous can be used. In addition, those having a plurality of crystal states from those having different crystal states may be included.

  The metal oxide particles may be subjected to various surface treatments on the surface. For example, treatment with an inorganic substance such as tin oxide, aluminum oxide, antimony oxide, zirconium oxide, or silicon oxide, or an organic substance such as stearic acid, a polyol, or an organic silicon compound may be performed. In particular, when titanium oxide particles are used, surface treatment with an organosilicon compound is preferable. Examples of organosilicon compounds include silicone oils such as dimethylpolysiloxane or methylhydrogenpolysiloxane, organosilanes such as methyldimethoxysilane and diphenyldidimethoxysilane, silazanes such as hexamethyldisilazane, vinyltrimethoxysilane, and γ-mercaptopropyltrimethyl. Silane coupling agents such as methoxysilane and γ-aminopropyltriethoxysilane are common, but the silane treatment agent represented by the structure of the following general formula (1) has good reactivity with metal oxide particles. It is the best treatment agent.

In the formula, R ¹ and R ² each independently represents an alkyl group, and more specifically represents a methyl group or an ethyl group. R ³ is an alkyl group or an alkoxy group, and more specifically represents a group selected from the group consisting of a methyl group, an ethyl group, a methoxy group, and an ethoxy group. In addition, although the outermost surface of these surface-treated particles is treated with such a treatment agent, it may be treated with a treatment agent such as aluminum oxide, silicon oxide or zirconium oxide before the treatment. I do not care. As the titanium oxide particles, only one type of particles may be used, or a plurality of types of particles may be mixed and used.

  As the metal oxide particles to be used, those having an average primary particle diameter of 500 nm or less are usually used, those having an average primary particle diameter of 1 nm to 100 nm are preferably used, and those having an average primary particle diameter of 5 to 50 nm are more preferably used. This average primary particle diameter can be obtained by an arithmetic average value of particle diameters directly observed by a transmission electron microscope (hereinafter, sometimes referred to as “TEM”).

  In addition, as the metal oxide particles to be used, those having various refractive indexes can be used, but any particles can be used as long as they can be usually used for an electrophotographic photoreceptor. Preferably, those having a refractive index of 1.4 or more and a refractive index of 3.0 or less are used. The refractive index of the metal oxide particles is described in various publications. For example, according to the filler utilization dictionary (edited by Filler Research Society, Taiseisha, 1994), it is as shown in Table 1 below.

Among the metal oxide particles, specific names of titanium oxide particles include ultrafine titanium oxide “TTO-55 (N)” that has not been surface-treated, and ultrafine titanium oxide that has been coated with Al ₂ O _3. “TTO-55 (A)”, “TTO-55 (B)”, ultrafine titanium oxide “TTO-55 (C)” surface-treated with stearic acid, surface treatment with Al ₂ O ₃ and organosiloxane Applied ultrafine titanium oxide “TTO-55 (S)”, high purity titanium oxide “CR-EL”, sulfuric acid method titanium oxide “R-550”, “R-580”, “R-630”, “R-” 670 "," R-680 "," R-780 "," A-100 "," A-220 "," W-10 ", chlorinated titanium oxide" CR-50 "," CR-58 "," CR-60 "," CR-60-2 "," CR-67 , Conductive titanium oxide “SN-100P”, “SN-100D”, “ET-300W” (above, manufactured by Ishihara Sangyo Co., Ltd.), “R-60”, “A-110”, “A-150” In addition to titanium oxide such as “SR-1”, “R-GL”, “R-5N”, “R-5N-2”, “R-52N”, “RK-” coated with Al ₂ O ₃ 1 "," a-SP _", was subjected to SiO 2, _Al 2 _{O 3} coating" R-GX "," R-7E ", _ZnO, were subjected to SiO 2, _Al 2 _{O 3} coating" R-650 " SiO ₂ , “R-61N” coated with Al ₂ O ₃ (manufactured by Sakai Chemical Industry Co., Ltd.), “TR-700” surface-treated with SiO ₂ , Al ₂ O ₃ , ZnO, surface-treated with SiO _{2, Al} 2 _{O 3} "TR-840", another "TA-500", "TA 100 "," TA-200 "," titanium oxide TA-300 ", etc. surface-untreated," TA-400 was subjected to a surface treatment with _Al 2 _{O 3} "(manufactured by Fuji Titanium), surface treatment not subjected to "MT-150 W", _"MT-500B", surface-treated with SiO 2, _Al 2 _{O 3} "MT-100SA", _"MT-500SA", SiO 2, _Al 2 _{O 3} and organosiloxane And "MT-100SAS", "MT-500SAS" (manufactured by Teika Co., Ltd.) and the like which have been surface-treated with the above.

  Moreover, as a specific brand name of aluminum oxide particles, “Aluminium Oxide C” (manufactured by Nippon Aerosil Co., Ltd.) and the like can be mentioned.

Moreover, as a concrete brand name of a silicon oxide particle, "200CF", "R972" (made by Nippon Aerosil Co., Ltd.), "KEP-30" (made by Nippon Shokubai Co., Ltd.), etc. are mentioned.
Moreover, "SN-100P" (made by Ishihara Sangyo Co., Ltd.) etc. are mentioned as a specific brand name of a tin oxide particle. And as a specific brand name of zinc oxide particles, “MZ-305S” (manufactured by Teika Co., Ltd.) can be mentioned, but the metal oxide particles usable in the present invention are not limited to these.

  In the coating solution for forming the undercoat layer of the electrophotographic photoreceptor of the present invention, the metal oxide particles are preferably used in the range of 0.5 to 4 parts by weight with respect to 1 part by weight of the binder resin.

<Binder resin>
As the binder resin used in the undercoat layer, it is usually used in a coating solution for forming an undercoat layer of an electrophotographic photosensitive member, is soluble in an organic solvent, and the formed undercoat layer forms a photosensitive layer. It is not particularly limited as long as it is insoluble in the organic solvent used in the coating liquid for use, or has low solubility and does not substantially mix.

  As such a binder resin, for example, phenoxy, epoxy, polyvinyl pyrrolidone, polyvinyl alcohol, casein, polyacrylic acid, celluloses, gelatin, starch, polyurethane, polyimide, polyamide and the like can be used alone or in a cured form together with a curing agent. However, among them, polyamide resins, in particular, polyamide resins such as alcohol-soluble copolymerized polyamides and modified polyamides are preferable because they exhibit good dispersibility and coating properties.

  As the polyamide resin, for example, so-called copolymer nylon obtained by copolymerizing 6-nylon, 66-nylon, 610-nylon, 11-nylon, 12-nylon, etc., N-alkoxymethyl modified nylon, N-alkoxyethyl modified Examples thereof include alcohol-soluble nylon resins such as a type in which nylon is chemically modified, such as nylon. Specific product names include, for example, “CM4000”, “CM8000” (manufactured by Toray), “F-30K”, “MF-30”, “EF-30T” (manufactured by Nagase Chemtech Co., Ltd.), and the like. It is done.

Among these polyamide resins, a copolymerized polyamide resin containing a diamine represented by the following general formula (2) as a constituent component is particularly preferably used.

In the above formula (2), R ^{4 to} R ⁷ represent a hydrogen atom or an organic substituent. m and n each independently represents an integer of 0 to 4, and when there are a plurality of substituents, these substituents may be different from each other. The organic substituent represented by R ^{4 to} R ⁷ is preferably a hydrocarbon group having 20 or less carbon atoms, which may contain a hetero atom, and more preferably a methyl group, an ethyl group, or an n-propyl group. Alkyl groups such as isopropyl group; alkoxy groups such as methoxy group, ethoxy group, n-propoxy group, isopropoxy group; aryl groups such as phenyl group, naphthyl group, anthryl group, pyrenyl group, etc., more preferably alkyl group Group or an alkoxy group. Particularly preferred is a methyl group or an ethyl group.

  Examples of the copolymer polyamide resin containing the diamine represented by the formula (2) as a constituent component include other lactams such as γ-butyrolactam, ε-caprolactam, lauryllactam; 1,4-butanedicarboxylic acid, 1, Dicarboxylic acids such as 12-dodecanedicarboxylic acid, 1,20-eicosanedicarboxylic acid; diamines such as 1,4-butanediamine, 1,6-hexamethylenediamine, 1,8-octamethylenediamine, 1,12-dodecanediamine A combination of piperazine and the like and copolymerized into binary, ternary, quaternary and the like. Although there is no limitation in particular about this copolymerization ratio, Usually, the diamine component represented by the said formula is 5-40 mol%, Preferably it is 5-30 mol%.

  The number average molecular weight of the copolymerized polyamide is preferably 10,000 to 50,000, particularly preferably 15,000 to 35,000. Even if the number average molecular weight is too small or too large, it is difficult to maintain the uniformity of the film. There is no particular limitation on the method for producing the copolymerized polyamide, and a normal polyamide polycondensation method is appropriately applied, and a melt polymerization method, a solution polymerization method, an interfacial polymerization method, or the like is used. In the polymerization, a monobasic acid such as acetic acid or benzoic acid, a monoacid base such as hexylamine or aniline, or a molecular weight regulator may be added.

  It is also possible to add a heat stabilizer represented by sodium phosphite, sodium hypophosphite, phosphorous acid, hypophosphorous acid and hindered phenol, and other polymerization additives. Specific examples of the copolymerized polyamide suitable for use in the present invention are shown below. However, in specific examples, the copolymerization ratio represents the charging ratio (molar ratio) of the monomer.

  The electrophotographic photoreceptor used in the image forming apparatus of the present invention preferably contains one or more curable resins. In particular, it is preferably used for the undercoat layer, and a thermosetting resin, a photocurable resin, an EB curable resin, or the like is preferably used as the curable resin. In any case, after application, a reaction occurs between the polymers and the like, crosslinking occurs, and the polymer is cured.

  Here, specific examples of the curable resin will be described. The thermosetting resin is a general term for a type of resin that is cured by a chemical reaction caused by heat. Specifically, there are phenol resin, urea resin, melamine resin, cured epoxy resin, urethane resin, unsaturated polyester resin, and the like. In addition, it is possible to impart curability by introducing a curable substituent into a normal thermoplastic polymer. Generally, it is a polymer having a cross-linked structure three-dimensionally, which may be called a condensation-type cross-linking polymer or an addition-type cross-linking polymer. Usually, in the production, the reaction proceeds with time and the reaction rate and the molecular weight increase. As a result, the elastic modulus increases, the specific volume decreases, and the solubility in the solvent decreases greatly.

  Next, a general thermosetting resin will be described. A phenolic resin is a synthetic resin made from phenols and formaldehyde, and has the advantage of being cheap and capable of forming a beautiful shape. In general, in the reaction of phenol (P) and formaldehyde (F), those having an F / P molar ratio of about 0.6 to 1 are obtained under acidic conditions, and resins of about 1 to 3 are obtained with a base catalyst. Generate.

  The urea resin is a synthetic resin formed by reacting urea with formalin, and has an advantage that it can be freely colored with a colorless and transparent solid. In general, in the reaction between urea and formaldehyde, polymethylene urea having no methylol group is produced under acidic conditions, and a mixture of methylol ureas is obtained under basic conditions.

  Melamine resin is a thermosetting resin obtained by the reaction of melamine derivatives and formaldehyde, and is more expensive than urea resin. However, it is superior in hardness, water resistance and heat resistance, and is colorless and transparent and free to color. It has the advantage that it can be made, and is excellent for lamination and adhesion.

  Epoxy resin is a general term for thermosetting resins that can be cured by graft polymerization with epoxy groups remaining in the polymer. When a prepolymer before graft polymerization and a curing agent are mixed and heat-cured, the product is completed, but both the prepolymer and the commercialized resin are called epoxy resins. The prepolymer is mainly a liquid compound having two or more epoxy groups in one molecule. By reaction (mainly polyaddition) of this polymer and various curing agents, a three-dimensional polymer is produced and becomes a cured epoxy resin. The cured epoxy resin has good adhesion and adhesion, and is excellent in heat resistance, chemical resistance, and electrical stability. General-purpose epoxy resins are bisphenol A diglycyl ether-based resins, but there are glycidyl ester-based resins, glycidyl amine-based resins, and cyclic aliphatic epoxy resins. Typical examples of the curing agent include aliphatic or aromatic polyamines, acid anhydrides, polyphenols, and the like, which react with an epoxy group by polyaddition to form a polymer and make it three-dimensional. Other curing agents include tertiary amines and Lewis acids.

  The urethane resin is a polymer compound obtained by copolymerizing a monomer with a urethane bond usually formed by condensation of an isocyanate group and an alcohol group. Usually, it is divided into a liquid main agent and a curing agent at room temperature, and the two liquids are polymerized by stirring and mixing to form a solid.

  The unsaturated polyester resin is divided into a resin and a curing agent that are liquid at room temperature, and the two liquids are polymerized by stirring and mixing them to form a solid. Although it has the feature of high transparency, there is a problem with respect to dimensional stability and the like due to large shrinkage during polymerization and curing. Since it is often sold in the form of a volatile solvent, it gradually deforms as the solvent evaporates after curing.

  A photocurable resin consists of what mixed oligomers (low polymer), such as epoxy acrylate and urethane acrylate, a reactive diluent (monomer), and a photoinitiator (benzoin type, acetophenone type, etc.).

  In addition to these, there are addition type footing polymers that use a copolymer of polyfunctional monomers such as divinylbenzene and ethylene glycol dimethacrylate.

  In addition, it is preferable to use a polymer other than a so-called curable resin in combination, and in particular, a polyamide resin such as an alcohol-soluble copolymer polyamide or the modified polyamide is preferable because it exhibits good dispersibility and coatability.

  Any organic solvent that can dissolve the binder resin for the undercoat layer can be used as the organic solvent for the coating solution for forming the undercoat layer. Specifically, alcohols having 5 or less carbon atoms such as methanol, ethanol, isopropyl alcohol, or normal propyl alcohol; halogens such as chloroform, 1,2-dichloroethane, dichloromethane, trichrene, carbon tetrachloride, 1,2-dichloropropane, etc. Hydrocarbons: Nitrogen-containing organic solvents such as dimethylformamide; aromatic hydrocarbons such as toluene and xylene, and the like. Among these, an arbitrary combination and a mixed solvent in an arbitrary ratio can be used. Moreover, even if it is an organic solvent which does not dissolve the binder resin for the undercoat layer alone, it can be used as long as it can be dissolved, for example, by using a mixed solvent with the above organic solvent. . In general, coating unevenness can be reduced by using a mixed solvent.

  The amount ratio of the organic solvent used in the coating solution for forming the undercoat layer and the solid content of the binder resin, titanium oxide particles, etc. varies depending on the coating method of the coating solution for forming the undercoat layer, and a uniform coating film in the applied coating method. May be used with appropriate modification so that the above is formed.

  The layer forming coating solution preferably contains metal oxide particles. In this case, the metal oxide particles are dispersed in the coating solution. In order to disperse the metal oxide particles in the coating solution, for example, it can be produced by wet dispersion in an organic solvent with a known mechanical grinding device such as a ball mill, a sand grind mill, a planetary mill, or a roll mill. However, it is preferable to disperse using a dispersion medium.

  As a dispersing device for dispersing using a dispersion medium, any known dispersing device may be used. Pebble mill, ball mill, sand mill, screen mill, gap mill, vibration mill, paint shaker, atomizer Examples include lighters. Among these, those that can be dispersed by circulating the coating liquid are preferable, and wet stirring ball mills such as a sand mill, a screen mill, and a gap mill are used from the viewpoints of dispersion efficiency, fineness of the final particle size, and ease of continuous operation. . These mills may be either vertical or horizontal. The disc shape of the mill can be any plate type, vertical pin type, horizontal pin type or the like. Preferably, a liquid circulation type sand mill is used.

  The wet stirring ball mill is supplied from a cylindrical stator, a slurry supply port provided at one end of the stator, a slurry discharge port provided at the other end of the stator, a medium filled in the stator, and a supply port. A pin, disk or annulus type rotor that stirs and mixes the prepared slurry, and is connected to the discharge port and rotates integrally with the rotor, or rotates independently of the rotor, and has centrifugal force. In a wet stirring ball mill composed of an impeller type separator that separates media and slurry by action and discharges the slurry from the discharge port, the shaft center for driving the separator to rotate is a hollow discharge port that communicates with the discharge port. Those are particularly preferred.

  According to such a wet stirring ball mill, the slurry from which the media is separated by the separator is discharged through the shaft center, but since the centrifugal force does not act on the shaft center, the slurry is discharged without kinetic energy. Is done. For this reason, kinetic energy is not wasted and useless power is not consumed.

  Such a wet stirring ball mill may be horizontally oriented, but is preferably vertically oriented in order to increase the filling rate of media, and a discharge port is provided at the upper end of the mill. It is also desirable to provide a separator above the media filling level. When the discharge port is provided at the upper end of the mill, the supply port is provided at the bottom of the mill. In a preferred embodiment, the supply port is composed of a valve seat and a V-shaped, trapezoidal, or cone-shaped valve body that is fitted to the valve seat so as to be movable up and down and can be in line contact with the edge of the valve seat. By forming an annular slit that prevents the passage of media between the V-shaped, trapezoidal, or cone-shaped valve body, the raw slurry is supplied, but the fall of the media can be prevented. . Further, the slit can be widened to raise the valve body to discharge the media, or the valve body can be lowered to close the slit and seal the mill. Further, since the slit is formed by the edge of the valve body and the valve seat, the coarse particles in the raw material slurry are difficult to bite, and even if it is bitten, it is easy to come out vertically and clogging is difficult to occur.

  Such a wet stirring ball mill is also preferably provided with a screen for separating the media at the bottom and a product slurry outlet, so that the product slurry remaining in the mill can be removed after the pulverization.

  In the present invention, the wet stirring ball mill applied to disperse the coating solution for forming the undercoat layer, which is suitable for use in the present invention, may be a separator or a screen or slit mechanism, but is preferably an impeller type. A mold is preferred. It is desirable that the wet stirring ball mill be oriented vertically and the separator be provided at the top of the mill. Particularly when the media filling rate is set to 80 to 90%, the grinding is most efficiently performed, and the separator is more than the media filling level. It is possible to position it above, and there is an effect that it is possible to prevent the medium from being ejected on the separator.

  Specific examples of the wet stirring ball mill having such a structure include an ultra apex mill manufactured by Kotobuki Industries Co., Ltd.

  Although there is no restriction | limiting in particular in the output of an ultrasonic oscillator, Usually 100W-5kW thing is used. Usually, it is better to disperse a small amount of coating liquid with ultrasonic waves with a small output ultrasonic oscillator than to process a large amount of coating liquid with ultrasonic waves with a high output ultrasonic oscillator. The amount of the undercoat layer-forming coating solution to be processed is preferably 1 to 50 L, more preferably 5 to 30 L, and particularly preferably 10 to 20 L. In this case, the output of the ultrasonic oscillator is preferably 200 W to 3 kW, more preferably 300 W to 2 kW, and particularly preferably 500 W to 1.5 kW.

  The method of applying ultrasonic vibration to the coating solution for forming the undercoat layer is not particularly limited, but the method of directly immersing the ultrasonic oscillator in the container containing the coating solution for forming the undercoat layer, the coating for forming the undercoat layer Examples thereof include a method in which an ultrasonic oscillator is brought into contact with the outer wall of the container in which the liquid is stored, and a method in which a solution containing the coating liquid for forming the undercoat layer is immersed in a liquid that has been vibrated by the ultrasonic transmitter. Among these methods, a method of immersing a solution containing the coating solution for forming the undercoat layer in a liquid that has been vibrated by an ultrasonic transmitter is preferably used. In this case, the liquid to be vibrated by the ultrasonic transmitter includes water; alcohols such as methanol; aromatic hydrocarbons such as toluene; and fats and oils such as silicone oil. In view of cleaning properties, it is preferable to use water. In the method of immersing a solution containing a coating liquid for forming an undercoat layer in a liquid that has been vibrated by an ultrasonic transmitter, the efficiency of ultrasonic treatment changes depending on the temperature of the liquid. It is preferable to keep it constant. The temperature of the liquid to which vibration is applied may increase due to the applied ultrasonic vibration. The temperature of the liquid is usually 5 to 60 ° C, preferably 10 to 50 ° C, and more preferably 15 to 40 ° C.

  The container for storing the coating solution for forming the undercoat layer during the ultrasonic treatment is a container that is usually used for containing the coating solution for forming the undercoat layer used for forming the photosensitive layer for the electrophotographic photoreceptor. Any container may be used as long as it is a resin container such as polyethylene and polypropylene, a glass container, and a metal can. Among these, metal cans are preferable, and 18 L metal cans are particularly preferably used as defined in JIS Z1602. This is because it is hardly affected by organic solvents and is strong against impact.

  The coating solution for forming the undercoat layer is used after being filtered as necessary in order to remove coarse particles. As the filtration media in this case, any filtration media such as cellulose fiber, resin fiber, glass fiber, etc., which are usually used for filtration may be used. As a form of the filtration media, a so-called wind filter in which various fibers are wound around a core material is preferable due to a large filtration area and high efficiency. As the core material, any conventionally known core material can be used, and examples thereof include a stainless steel core material and a resin-made core material that does not dissolve in an undercoat layer forming coating solution such as polypropylene.

  The coating solution for forming the undercoat layer thus produced is used for forming the undercoat layer by further adding a binder or various auxiliary agents if desired.

In order to disperse the metal oxide particles such as titanium oxide particles in the coating solution for the undercoat layer, it is preferable to use a dispersion medium having an average particle diameter of 5 μm to 200 μm.
Since the dispersion media usually has a shape close to a true sphere, the average particle diameter can be obtained by, for example, a method of sieving with a sieve described in JIS Z8801: 2000 or the like, or measurement by image analysis. Thus, the density can be measured. Specifically, for example, the average particle diameter and sphericity can be measured by an image analyzer represented by LUZEX50 manufactured by Nireco Corporation. The average particle diameter of the dispersion medium is usually 5 μm to 200 μm, and more preferably 10 μm to 100 μm. In general, a dispersion medium having a small particle diameter tends to give a uniform dispersion in a short time. However, if the particle diameter is excessively small, the mass of the dispersion medium becomes too small to perform efficient dispersion.

The density of the dispersion medium is usually 5.5 g / cm ³ or more, preferably 5.9 g / cm ³ or more, more preferably 6.0 g / cm ³ or more. Generally, dispersion using a higher density dispersion medium tends to give a uniform dispersion in a shorter time. The sphericity of the dispersion medium is preferably 1.08 or less, more preferably a dispersion medium having a sphericity of 1.07 or less.

  The material of the dispersion medium is insoluble in the coating solution for forming the undercoat layer and has a specific gravity larger than that of the coating solution for forming the undercoat layer and reacts with the coating solution for forming the undercoat layer, Any known dispersion medium can be used as long as it does not alter the forming coating liquid, and steel balls such as chrome balls (ball balls for ball bearings) and carbon balls (carbon steel balls); stainless steel balls; Ceramic spheres such as silicon nitride spheres, silicon carbide, zirconia, and alumina; spheres coated with a film of titanium nitride, titanium carbonitride, etc. are mentioned, among these, ceramic spheres are preferable, and zirconia fired balls are particularly preferable. . More specifically, it is particularly preferable to use zirconia fired beads described in Japanese Patent No. 3400836.

<Undercoat layer forming method>
In the present invention, the preferred undercoat layer is a dip coating, spray coating, nozzle coating, spiral coating, ring coating, bar coating coating, roll coating coating, blade coating, etc., on the support. It forms by apply | coating by the well-known coating method of this, and drying.

  Spray coating methods include air spray, airless spray, electrostatic air spray, electrostatic airless spray, rotary atomizing electrostatic spray, hot spray, and hot airless spray. Considering the degree of conversion, adhesion efficiency, etc., in the rotary atomizing electrostatic spray, the conveying method disclosed in the republished Japanese Patent Publication No. 1-805198, that is, the cylindrical workpiece is rotated while the axial direction is spaced. By continuously transporting the electrophotographic photosensitive member, an electrophotographic photosensitive member excellent in film thickness uniformity can be obtained with a comprehensively high adhesion efficiency.

  Examples of the spiral coating method include a method using a liquid injection coating machine or a curtain coating machine disclosed in Japanese Patent Laid-Open No. 52-119651, and a coating liquid from a minute opening disclosed in Japanese Patent Laid-Open No. 1-2231966. And a method using a multi-nozzle body disclosed in JP-A-3-193161.

  In the case of the dip coating method, the total solid concentration of the coating solution for forming the undercoat layer is usually 1% by mass or more, preferably 10% by mass or more, and usually 50% by mass or less, preferably 35% by mass or less. The viscosity is preferably 0.1 mPa · s or more, and preferably 100 mPa · s or less.

  Thereafter, the coating film is dried, and the drying temperature and time are adjusted so that necessary and sufficient drying is performed. The drying temperature is usually 100 to 250 ° C, preferably 110 ° C to 170 ° C, more preferably 115 ° C to 140 ° C. As a drying method, a hot air dryer, a steam dryer, an infrared dryer, and a far infrared dryer can be used.

<Charge generating material>
The photosensitive layer formed on the conductive support may have a single layer structure in which the charge generation material and the charge transport material are present in the same layer and dispersed in the binder resin, or the charge generation material may be Any of a layered structure in which the charge generation layer dispersed in the binder resin and the charge transport material dispersed in the binder resin are functionally separated may be used.

  The electrophotographic photosensitive member that can be used in the present invention has a Bragg angle (2θ ± 0.2 °) of 9.0 ° and 27.2 ° with respect to CuKα characteristic X-rays (wavelength 1.541 mm) in the photosensitive layer. Oxytitanium phthalocyanine having a peak and having at least one main diffraction peak in the range of 9.3 ° to 9.8 ° (hereinafter referred to as “oxytitanium phthalocyanine having a specific crystal type” as appropriate) is contained. The measuring method of Bragg angle (diffraction peak) with respect to CuKα characteristic X-ray (wavelength 1.541Å) and the definition in the present invention are based on the method described in the examples.

  Oxytitanium phthalocyanine having a specific crystal type that can be used in the present invention is mainly diffracted at Bragg angles (2θ ± 0.2 °) of 9.0 ° and 27.2 ° with respect to CuKα characteristic X-ray (wavelength 1.541Å). As long as it has a peak and has at least one main diffraction peak in the range of 9.3 ° to 9.8 °, any other diffraction peak may be included. Other peak positions that may be included include peaks at 14.3 °, 14.8 °, 18.0 °, 23.8 °, 24.2 °, etc. In view of characteristics, it has at least one of the above peaks in addition to the main diffraction peak at 9.0 °, 27.2 ° and at least one main diffraction peak in the range of 9.3 ° to 9.8 °. It is preferable to have two or more, more preferably three or more.

  The peak at 9.3 ° to 9.8 ° only needs to have at least one main diffraction peak within 9.3 ° to 9.8 °, but it is 9.4 from the viewpoint of crystal stability. It is preferable to have at least one main diffraction peak in the range of ° to 9.7 °, and more preferably to have a main diffraction peak in the vicinity of 9.4 ° to 9.6 °. The number of peaks at 9.3 ° to 9.8 ° may be at least one, but it is also possible to have a plurality of peaks.

  The effect of the present invention can be obtained by using an electrophotographic photoreceptor containing oxytitanium phthalocyanine having a specific crystal type in a photosensitive layer. As a method for incorporating the oxytitanium phthalocyanine having the specific crystal type into the photosensitive layer, low crystalline oxytitanium phthalocyanine or amorphous oxytitanium phthalocyanine which is a precursor of the oxytitanium phthalocyanine crystal having the specific crystal type is used as an organic solvent. Oxytitanium phthalocyanine having a specific crystal type is obtained by contact and crystal conversion, and an electrophotographic photosensitive member is produced using the obtained oxytitanium phthalocyanine, whereby an oxytitanium having a specific crystal type is formed in the photosensitive layer. A method for obtaining an electrophotographic photoreceptor containing phthalocyanine, or a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to a CuKα characteristic X-ray (wavelength 1.541Å) different from the specific crystal type Oxytitanium phthalo By using cyanine and converting it to oxytitanium phthalocyanine having a specific crystal type in the process of preparing a photoreceptor such as when preparing a coating solution for forming a photosensitive layer, oxytitanium having a specific crystal type in the photosensitive layer Examples include a method of obtaining an electrophotographic photoreceptor containing phthalocyanine, and any method can be used, but from the viewpoint of difficulty and production efficiency of crystal form conversion to oxytitanium phthalocyanine having a specific crystal form, For forming a photosensitive layer using oxytitanium phthalocyanine having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to a CuKα characteristic X-ray (wavelength 1.541Å) different from the specific crystal type To the oxytitanium phthalocyanine having a specific crystal type in the process of preparing a photoreceptor, such as when preparing a coating solution A method of obtaining an electrophotographic photosensitive member containing oxytitanium phthalocyanine having a specific crystal type in the photosensitive layer is preferable.

  Any known oxytitanium phthalocyanine having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to a CuKα characteristic X-ray (wavelength 1.541Å) different from the specific crystal type described above However, the Bragg angles (2θ ± 0.2 °) with respect to CuKα characteristic X-rays (wavelength 1.541 mm) are preferably 9.0 °, 14.2 °, 23.9 ° and 27.1 °. It is preferable to use oxytitanium phthalocyanine having a diffraction peak.

  Oxytitanium having a specific crystal type from oxytitanium phthalocyanine having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to CuKα characteristic X-rays (wavelength 1.541Å) different from the specific crystal type described above Any known method can be used as a conversion method to phthalocyanine, but a method of converting by applying mechanical and physical force in a medium such as an organic solvent, or a CuKα characteristic X different from a specific crystal type. It is preferable to perform the conversion by colliding dispersed dispersions of oxytitanium phthalocyanine having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 27.2 ° with respect to the line (wavelength 1.541Å).

  Examples of methods for mechanically and physically applying force include planetary mills, vibrating ball mills, CF mills, roller mills, sand mills, kneaders, paint shakers, etc. When using these devices, glass beads, Known media such as steel beads, alumina beads, and zirconia beads may be used in combination.

  In the present invention, in addition to oxytitanium phthalocyanine having a specific crystal type, other charge generation materials and dyes / pigments can be used as necessary. Examples of this include selenium and its alloys, cadmium sulfide, other inorganic photoconductive materials, phthalocyanine pigments, azo pigments, dithioketopyrrolopyrrole pigments, squalene pigments, quinacridone pigments, indigo pigments, perylene pigments, polycyclic pigments Various photoconductive materials such as organic pigments such as quinone pigments, anthanthrone pigments and benzimidazole pigments can be used. In the present invention, it is particularly preferable to use organic pigments, further phthalocyanine pigments, and azo pigments.

  Specific examples of the phthalocyanine used include metal-free phthalocyanine, copper, indium, gallium, tin, titanium, zinc, vanadium, silicon, germanium, and other metals, or oxides, halides, hydroxides, and alkoxides thereof. Various crystal forms of such coordinated phthalocyanines are used. In particular, oxytitanium phthalocyanines (also known as oxy: oxy) such as X-type, τ-type metal-free phthalocyanine, A-type (also known as β-type), B-type (also known as α-type), D-type (also known as Y-type), which are highly sensitive crystal types Titanium phthalocyanine), vanadyl phthalocyanine, chloroindium phthalocyanine, chlorogallium phthalocyanine such as type II, hydroxygallium phthalocyanine such as type V, μ-oxo-gallium phthalocyanine dimer such as type G and type I, μ-type such as type II Oxo-aluminum phthalocyanine dimer is preferred. Among these phthalocyanines, A type (β type), B type (α type), D type (Y type) oxytitanium phthalocyanine, II type chlorogallium phthalocyanine, V type hydroxygallium phthalocyanine, G type μ-oxo- Gallium phthalocyanine dimer and the like are particularly preferable.

Moreover, when using an azo pigment together, a bisazo pigment, a trisazo pigment, etc. are used suitably. Examples of preferred azo pigments are shown below. In the following general formula, Cp ¹ to Cp ³ represent couplers.

The couplers Cp ¹ to Cp ³ preferably have the following structures.

  Examples of the binder resin used in the charge generation layer in the multilayer photoreceptor include polyvinyl butyral resin, polyvinyl formal resin, and polyvinyl acetal such as partially acetalized polyvinyl butyral resin in which a part of butyral is modified with formal or acetal. Resin, polyarylate resin, polycarbonate resin, polyester resin, modified ether polyester resin, phenoxy resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyvinyl acetate resin, polystyrene resin, acrylic resin, methacrylic resin, polyacrylamide resin, Polyamide resin, polyvinyl pyridine resin, cellulose resin, polyurethane resin, epoxy resin, silicone resin, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, casein, salt Vinyl chloride-vinyl acetate copolymer such as vinyl-vinyl acetate copolymer, hydroxy-modified vinyl chloride-vinyl acetate copolymer, carboxyl-modified vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer Copolymer, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, styrene-alkyd resin, silicone-alkyd resin, phenol-formaldehyde resin and other insulating resins, poly-N-vinylcarbazole, polyvinylanthracene, It can be selected from organic photoconductive polymers such as polyvinyl perylene, but is not limited to these polymers. These binder resins may be used alone or in combination of two or more. Among these, polyvinyl butyral resin, polyvinyl formal resin, and a part of butyral are preferably formal, and polyvinyl acetal resins such as partially acetalized polyvinyl butyral resin modified with acetal or the like are particularly preferable.

  Solvents used for the preparation of coating solutions and dispersion media for dissolving the binder resin include, for example, saturated aliphatic solvents such as pentane, hexane, octane and nonane, aromatic solvents such as toluene, xylene and anisole, chlorobenzene, Halogenated aromatic solvents such as dichlorobenzene and chloronaphthalene, amide solvents such as dimethylformamide and N-methyl-2-pyrrolidone, alcohol solvents such as methanol, ethanol, isopropanol, n-butanol and benzyl alcohol, glycerin, Aliphatic polyhydric alcohols such as polyethylene glycol, chain, branched and cyclic ketone solvents such as acetone, cyclohexanone, methyl ethyl ketone, 4-methoxy-4-methyl-2-pentanone, methyl formate, ethyl acetate, n-butyl acetate Esters such as Medium, halogenated hydrocarbon solvents such as methylene chloride, chloroform, 1,2-dichloroethane, chain ethers such as diethyl ether, dimethoxyethane, tetrahydrofuran, 1,4-dioxane, methyl cellosolve, ethyl cellosolve, and cyclic ethers Solvents, acetonitrile, dimethyl sulfoxide, sulfolane, aprotic polar solvents such as hexamethylphosphate triamide, n-butylamine, isopropanolamine, diethylamine, triethanolamine, nitrogen-containing compounds such as ethylenediamine, triethylenediamine, triethylamine, ligroin, etc. Mineral oil, water and the like, and those which do not dissolve the undercoat layer described later are preferably used. These can be used alone or in combination of two or more.

  In the charge generation layer of the multilayer photoreceptor, the blending ratio (weight) of the binder resin and the charge generation material is in the range of 10 to 1000 parts by weight, preferably 30 to 500 parts by weight with respect to 100 parts by weight of the binder resin. The film thickness is usually 0.1 μm to 4 μm, preferably 0.15 μm to 0.6 μm. If the ratio of the charge generation material is too high, the stability of the coating solution is lowered due to problems such as aggregation of the charge generation material, while if it is too low, the sensitivity as a photoconductor is reduced. It is preferable to do. As a method for dispersing the charge generating substance, a known dispersion method such as a ball mill dispersion method, an attritor dispersion method, or a sand mill dispersion method can be used. In this case, it is effective to refine the particles to a particle size of 0.5 μm or less, preferably 0.3 μm or less, more preferably 0.15 μm or less.

  The stacked charge generation layer contains the above-described charge generation material, but preferably contains a charge transport material described later from the viewpoint of fine line reproducibility. A preferable blending ratio is 0.1 mol or more and 5 mol or less of the charge transport material with respect to 1 mol of the charge generation material. More preferably, it is 0.2 mol or more, More preferably, it is 0.5 mol or more. If the upper limit is too large, the sensitivity may be lowered. Therefore, the upper limit is preferably 3 mol or less, and more preferably 2 mol or less.

<Charge transport material>
The photosensitive layer formed on the conductive support may have a single layer structure in which the charge generation material and the charge transport material are present in the same layer and dispersed in the binder resin, or the charge generation material may be It may be any one of a layered structure in which the charge generation layer dispersed in the binder resin and the charge transport material are functionally separated into the charge transport layer dispersed in the binder resin. And other components used depending on the condition. Specifically, the charge transport layer is prepared by, for example, preparing a coating solution by dissolving or dispersing a charge transport material and a binder resin in a solvent. In the case of an inversely laminated photosensitive layer, it can be obtained by applying and drying on a conductive support (on the intermediate layer when an intermediate layer is provided).

  The photoreceptor in the present invention preferably contains a charge transport material having an ionization potential of 4.8 eV or more and 5.8 eV or less as a charge transport material. The ionization potential can be easily measured using AC-1 (manufactured by Riken) in the atmosphere using a powder or a film. If it is too small, it becomes weak against ozone or the like, so it is preferably 4.9 eV or more, more preferably 5.0 eV or more. If the value of the ionization potential is too large, the charge injection efficiency from the charge generating material is deteriorated, so that it is preferably 5.6 eV or less, more preferably 5.5 eV or less, and even more preferably 5.4 eV or less.

Specifically, the photoreceptor in the present invention preferably contains a compound represented by the following general formula (5).
[In General Formula (5), Ar ¹ to Ar ⁶ each independently represent an aromatic residue that may have a substituent or an aliphatic residue that may have a substituent, and X ¹ Represents an organic residue, R ¹ to R ⁴ each independently represents an organic group, and n 1 to n 6 each independently represents an integer of 0 to 2. ]

In the general formula (5), Ar ¹ to Ar ⁶ each independently represent an aromatic residue that may have a substituent or an aliphatic residue that may have a substituent. Specific aromatics include aromatic hydrocarbons such as benzene, naphthalene, anthracene, pyrene, perylene, phenanthrene, and fluorene, and aromatic heterocycles such as thiophene, pyrrole, carbazole, and imidazole. The number of carbon atoms is preferably 5 to 20, more preferably 16 or less, and still more preferably 10 or less. The lower limit is preferably 6 or more from the viewpoint of electrical characteristics. In particular, an aromatic hydrocarbon residue is preferable, and a benzene residue is preferable.

  Further, the specific aliphatic group preferably has 1 to 20 carbon atoms, more preferably 16 or less, and still more preferably 10 or less. In the case of a saturated aliphatic group, 6 or less carbon atoms are preferable, and in the case of an unsaturated aliphatic group, 2 or more carbon atoms are preferable. Examples of the saturated aliphatic include branched and straight chain alkyl such as methane, ethane, propane, isopropane, and isobutane, and examples of the unsaturated aliphatic include alkenes such as ethylene and butylene.

  In addition, the substituent to be substituted for these is not particularly limited, and specifically, an alkyl group such as a methyl group, an ethyl group, a propyl group, and an isopropyl group; an alkenyl group such as an allyl group; a methoxy group, and an ethoxy group And alkoxy groups such as propoxy group; aryl groups such as phenyl group, indenyl group, naphthyl group, acenaphthyl group, phenanthryl group and pyrenyl group; and heterocyclic groups such as indolyl group, quinolyl group and carbazolyl group. These substituents may be linked to each other to form a ring.

  In addition, these substituents, when introduced, have the effect of adjusting the intramolecular charge and increasing the charge mobility. On the other hand, if the bulk becomes too large, the distortion of the conjugated surface in the molecule, the intermolecular steric structure, In order to reduce charge mobility by repulsion, the number of carbon atoms is preferably 1 or more, preferably 6 or less, more preferably 4 or less, and particularly 2 or less.

  In addition, in the case of having a substituent, it is preferable to have a plurality of substituents, because it avoids crystal precipitation. However, if it is too much, the charge mobility is lowered due to distortion of the conjugate plane in the molecule and intermolecular steric repulsion. , Preferably no more than 2 per ring. And in order to improve the stability in the photosensitive layer and improve the electrical characteristics, those which are not sterically bulky are preferred, and more specifically, a methyl group, an ethyl group, a butyl group, an isopropyl group or a methoxy group preferable.

In particular, when Ar ¹ to Ar ⁴ are benzene residues, it is preferable to have a substituent. In this case, a preferable substituent is an alkyl group, and a methyl group is particularly preferable. In addition, when Ar ⁵ to Ar ⁶ are benzene residues, preferred substituents are a methyl group or a methoxy group. In particular, in general formula (5), Ar ¹ preferably has a fluorene structure.

In the general formula (5), X ¹ is an organic residue, for example, an aromatic residue, saturated aliphatic residue, heterocyclic residue, or ether structure which may have a substituent. Organic residues, organic residues having a divinyl structure, and the like can be mentioned. Particularly preferred are organic residues having 1 to 15 carbon atoms, and among them, aromatic residues and saturated aliphatic residues are preferred. In the case of an aromatic residue, the number of carbon atoms is preferably 6 or more and 14 or less, and more preferably 10 or less. In the case of a saturated aliphatic residue, it is preferably 1 to 10 carbon atoms, more preferably 8 or less.

The organic residue X ¹ may have a substituent on the structure listed above. Substituents for substitution are not particularly limited, but are alkyl groups such as methyl, ethyl, propyl, and isopropyl groups; alkenyl groups such as allyl groups; alkoxy groups such as methoxy groups, ethoxy groups, and propoxy groups. An aryl group such as a phenyl group, an indenyl group, a naphthyl group, an acenaphthyl group, a phenanthryl group, and a pyrenyl group; and a heterocyclic group such as an indolyl group, a quinolyl group, and a carbazolyl group. These substituents may be linked to each other to form a ring. These substituents preferably have 1 or more carbon atoms, preferably 10 or less carbon atoms, more preferably 6 or less carbon atoms, and particularly 3 or less carbon atoms. More specifically, a methyl group, an ethyl group, a butyl group, an isopropyl group, a methoxy group, and the like are preferable.

In addition, in the case of having a substituent, having a plurality of substituents is preferable because it avoids crystal precipitation. However, if it is too much, the charge mobility is lowered due to distortion of the conjugate plane in the molecule and intermolecular steric repulsion. Therefore, it is preferably 2 or less per one X ¹ .

R ¹ to R ⁴ each independently represents an integer of 0 to 2. n1 is preferably 1, and n2 is preferably 0 or 1.

R ¹ to R ⁴ are each independently an organic group. An organic group having 30 or less carbon atoms is preferable, and an organic group having 20 or less is more preferable.

n5 to n6 each independently represents 0 to 2. When n5 is 0, it represents a direct connection, and when n6 is 0, n5 is preferably 0. When n5 and n6 are both 1, X ¹ is preferably an alkylidene, an arylene group, or an ether structure. As the alkylidene structure, phenylmethylidene, 2-methylpropylidene, 2-methylbutylidene, cyclohexylidene and the like are preferable. The arylene structure is preferably phenylene, naphthylene, or the like. Examples of a group having an ether structure, _-O-CH 2 -O-, and the like are preferable.

When n5 and n6 are both 0, Ar ⁵ is preferably a benzene residue or a fluorene residue. In the case of a benzene residue, it is preferable to substitute an alkyl group or an alkoxy group, more preferably a methyl group or a methoxy group, and preferably a p-position of a nitrogen atom. When n6 is 2, X ¹ is preferably a benzene residue.

Examples of specific combinations of n1 to n6 include the following.
n1 n2 n3 n4 n5 n6
1 0 0 0 0 0
1 1 0 0 0 0
1 0 1 0 0 1
1 1 1 1 0 1
2 2 0 0 0 0
1 0 0 0 0 0
2 2 2 2 1 1
1 1 1 0 2 1
1 1 1 1 1 2

Specific examples of structures suitable as charge transport materials in the present invention are shown below.

  In the above formula, R may be the same or different. Specifically, a hydrogen atom or a substituent; the substituent is preferably an alkyl group, an alkoxy group, an aryl group, or the like. Particularly preferred are a methyl group and a phenyl group. N is an integer of 0 to 2.

In addition, the charge transport material is obtained by structure optimization calculation using semi-empirical molecular orbital calculation using the AM1 parameter of the organic charge transporting material (hereinafter simply referred to as “semi-empirical molecular orbital calculation (AM1)”). It is preferable that the polarizability αcal satisfies 200 (＞ ³ )>α> 55 (Å ³ ). Moreover, it is preferable that 0.2 (D) <P <2.1 (D) is satisfied with respect to the dipole moment Pcal by the semiempirical molecular orbital calculation using the AM1 parameter.

  In the past, there were reports that used PM3 for calculation of charge transport materials, but AM1 was used in the present invention. The reason is as follows.

Reason 1 Charge transport materials are often formed from carbon, hydrogen, oxygen, and nitrogen, and the use of AM1 in which these parameters are fixed is expected to be suitable for structural optimization.
Reason 2 In the charge distribution calculation necessary to calculate the dipole moment, AM1 has higher reliability than PM3 or the like.

  In view of fine line reproducibility, the polarizability αcal is preferably 70 or more, and more preferably 90 or more. Considering the effect of image change due to repetition, it is more preferably 180 or less, preferably 150 or less, and more preferably 130 or less.

  The dipole moment Pcal is preferably 0.4 (D) or more, more preferably 0.6 (D) or more in view of memory by transfer. In view of mobility, it is preferably 2.0 (D) or less, more preferably 1.7 (D) or less, particularly preferably 1.5 (D) or less, and still more preferably 1. 3 (D) or less.

  Moreover, you may use together the compound of General formula (5), and arbitrary well-known charge transport substances. Examples of known charge transport materials include aromatic nitro compounds such as 2,4,7-trinitrofluorenone, cyano compounds such as tetracyanoquinodimethane, electron withdrawing materials such as quinone compounds such as diphenoquinone, and carbazole derivatives. , Indole derivatives, imidazole derivatives, oxazole derivatives, pyrazole derivatives, thiadiazole derivatives, heterocyclic compounds such as benzofuran derivatives, aniline derivatives, hydrazone derivatives, aromatic amine derivatives, stilbene derivatives, butadiene derivatives, enamine derivatives and multiple types of these compounds Or an electron donating substance such as a polymer having a group composed of these compounds in the main chain or side chain. Among these, carbazole derivatives, aromatic amine derivatives, stilbene derivatives, butadiene derivatives, enamine derivatives, and those in which a plurality of these compounds are bonded are preferable. Any one of these charge transport materials may be used alone, or two or more thereof may be used in any combination.

<Binder resin>
In forming a charge transport layer of a function-separated type photoreceptor having a charge generation layer and a charge transport layer, and a photosensitive layer of a single layer type photoreceptor, a binder resin is used to disperse the compound in order to ensure film strength. . In the case of the charge transport layer of the functional separation type photoreceptor, a coating solution obtained by dissolving or dispersing the charge transport material and various binder resins in a solvent, and in the case of a single layer type photoreceptor, the charge generation material and the charge transport. It can be obtained by applying and drying a coating solution obtained by dissolving or dispersing the substance and various binder resins in a solvent. Examples of the binder resin include polymers and copolymers of vinyl compounds such as butadiene resin, styrene resin, vinyl acetate resin, vinyl chloride resin, acrylic acid ester resin, methacrylic acid ester resin, vinyl alcohol resin, ethyl vinyl ether, polyvinyl Butyral resin, polyvinyl formal resin, partially modified polyvinyl acetal, polycarbonate resin, polyester resin, polyarylate resin, polyamide resin, polyurethane resin, cellulose ester resin, phenoxy resin, silicone resin, silicone-alkyd resin, poly-N-vinylcarbazole resin Etc. These resins may be modified with a silicon reagent or the like.

  In particular, in the present invention, it is preferable to contain one or more kinds of polymers obtained by interfacial polymerization. Interfacial polymerization is a polymerization method that utilizes a polycondensation reaction that proceeds at the interface of two or more solvents (mostly organic solvents-water systems) that do not mix with each other. For example, a dicarboxylic acid chloride is dissolved in an organic solvent, a glycol component is dissolved in alkaline water, etc., and both liquids are mixed at room temperature to be separated into two phases. At the interface, a polycondensation reaction proceeds to produce a polymer. Let Examples of other two components include phosgene and an aqueous glycol solution. Further, as in the case of condensing a polycarbonate oligomer by interfacial polymerization, the two components may not be divided into two phases, but the interface may be used as a polymerization field.

  As the reaction solvent, it is preferable to use two layers of an organic phase and an aqueous phase. The organic phase is preferably methylene chloride, and the aqueous phase is preferably an alkaline aqueous solution. A catalyst is preferably used during the interfacial polymerization reaction. The amount of condensation catalyst used in the reaction is, for example, 0.005 to 0 with respect to the glycol component when interfacial polymerization is performed using the glycol component. About 1 mol%, preferably 0.03 to 0.08 mol%. If it exceeds 0.1 mol%, a great deal of labor may be required for extraction and removal of the catalyst in the washing step after polycondensation.

  The reaction temperature is 80 ° C. or less, preferably 60 ° C. or less, more preferably 10 ° C. to 50 ° C., and the reaction time depends on the reaction temperature, but usually 0.5 minutes to 10 minutes. Time, preferably 1 minute to 2 hours. If the reaction temperature is too high, the side reaction cannot be controlled. On the other hand, if the reaction temperature is too low, the reaction control is preferable, but the refrigeration load may increase and the cost may increase accordingly.

  Moreover, the density | concentration in an organic phase should just be a range with which the composition obtained is soluble, Specifically, it is about 10-40 mass%. The proportion of the organic phase is preferably a volume ratio of 0.2 to 1.0 with respect to the aqueous alkali metal hydroxide solution of diol, that is, the aqueous phase.

  Moreover, it is preferable that the quantity of a solvent is adjusted so that the density | concentration of the production | generation resin in the organic phase obtained by polycondensation may be 5-30 mass%. Thereafter, an aqueous phase containing water and alkali metal hydroxide is newly added, and in order to further adjust the polycondensation conditions, a condensation catalyst is preferably added and the desired polycondensation is completed according to the interfacial polycondensation method. The ratio of the organic phase to the aqueous phase during polycondensation is preferably about 1: 0.2 to 1 in terms of volume ratio.

  The polymer produced by interfacial polymerization is particularly preferably a polycarbonate resin or a polyester resin (particularly a polyarylate resin is preferred). The polymer is preferably a polymer using an aromatic diol as a raw material, and a preferable aromatic diol structure is represented by the following formula (A).

[In Formula (A), X ² represents a single bond or a linking group, and Y ¹ to Y ⁸ each independently represent a hydrogen atom or a substituent having 20 or less atoms. ]

In formula (A), X ² is preferably a single bond or a linking group represented by the following structure. The “single bond” refers to a state in which there are no atoms “X ² ” and the two left and right benzene rings in the formula (A) are simply bonded by a single bond. Among them, X ² preferably has no cyclic structure.

In the above structure, R ^1a and R ^2a each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an optionally substituted aryl group, or a halogenated alkyl group, and Z represents the number of carbon atoms. 4 to 20 hydrocarbon groups which may be substituted are shown.

  In particular, a polycarbonate resin and a polyarylate resin containing a bisphenol or a biphenol component having the following structural formula are preferable from the viewpoints of sensitivity and residual potential, and among them, a polycarbonate resin is more preferable from the viewpoint of mobility.

  The structure of bisphenol and biphenol that can be suitably used for the polycarbonate resin is exemplified below. This illustration is made for the sake of clarity, and is not limited to the illustrated structure unless it is contrary to the spirit of the present invention.

In particular, in order to maximize the effects of the present invention, a polycarbonate containing a bisphenol derivative having the following structure is preferable.

In order to improve mechanical properties, it is preferable to use polyester, particularly polyarylate, and in this case, it is preferable to use the following structure as a bisphenol component,
As the acid component, the following structure is preferably used.

  Further, when terephthalic acid and isophthalic acid are used, it is preferable that the molar ratio of terephthalic acid is large.

  The ratio of the binder resin and the charge transport material used in the charge transport layer of the multilayer photoreceptor and the photosensitive layer of the single layer photoreceptor is usually 100 parts by weight of the binder resin in both the single layer and multilayer. The charge transport material is 20 parts by weight or more, preferably 30 parts by weight or more from the viewpoint of reducing residual potential, and more preferably 40 parts by weight or more from the viewpoint of stability during repeated use and charge mobility. On the other hand, from the viewpoint of thermal stability of the photosensitive layer, it is usually 150 parts by weight or less, preferably 120 parts by weight or less from the viewpoint of compatibility between the charge transport material and the binder resin, and from the viewpoint of printing durability. The amount is more preferably 100 parts by weight or less, and particularly preferably 80 parts by weight or less from the viewpoint of scratch resistance.

  In the case of a single-layer type photoreceptor, the charge generating substance is further dispersed in the charge transport medium having the above-described blending ratio. In this case, the particle size of the charge generating material needs to be sufficiently small, preferably 1 μm or less, more preferably 0.5 μm or less. If the amount of the charge generating material dispersed in the photosensitive layer is too small, sufficient sensitivity cannot be obtained. If the amount is too large, there is an adverse effect of chargeability and sensitivity. For example, preferably 0.1 to 50% by mass. It is used in the range, preferably in the range of 1 to 20% by mass.

  The film thickness of the photosensitive layer of the single-layer type photoreceptor is usually 5 to 100 μm, preferably 10 to 50 μm. The film thickness of the charge transport layer of the forward laminated photoreceptor is usually 5 to 50 μm. Although used, it is preferably 10 to 45 μm from the viewpoint of long life and image stability, and more preferably 10 to 30 μm from the viewpoint of high resolution.

  The photosensitive layer has well-known antioxidants, plasticizers, ultraviolet absorbers, electron-withdrawing compounds to improve film forming properties, flexibility, coating properties, stain resistance, gas resistance, light resistance, etc. Further, additives such as a leveling agent and a visible light shielding agent may be contained. In addition, the photosensitive layer may contain various additives such as a leveling agent, an antioxidant, and a sensitizer for improving the coating property as necessary. Examples of the antioxidant include hindered phenol compounds and hindered amine compounds. Examples of the visible light blocking agent include various dye compounds and azo compounds, and examples of the leveling agent include silicone oil and fluorine oil.

<Antioxidant>
Antioxidants are one type of stabilizer added to prevent oxidation of members contained in the photoreceptor. Antioxidants function as radical scavengers, and specific examples include phenol derivatives, amine compounds, phosphonic acid esters, sulfur compounds, vitamins, vitamin derivatives, and the like. Of these, phenol derivatives, amine compounds, vitamins and the like are preferable. Particularly preferably, a hindered phenol or a trialkylamine derivative having a bulky substituent in the vicinity of the hydroxy group is preferred. In particular, an aryl compound derivative having a t-butyl group at the o-position of the hydroxy group is preferable, and an aryl compound derivative having two t-butyl groups at the o-position of the hydroxy group is preferable.

  In addition, if the molecular weight of the antioxidant is too large, a problem may occur in the antioxidant ability, and a compound having a molecular weight of 1500 or less, particularly 1000 or less is preferable. The lower limit is 100 or more, preferably 150 or more, and more preferably 200 or more.

  Hereinafter, the antioxidant which can be used for this invention is shown. As the antioxidant that can be used in the present invention, all known materials can be used as antioxidants for plastics, rubber, petroleum, oils and fats, ultraviolet absorbers, and light stabilizers. The selected material can be preferably used.

(1) Phenols described in JP-A No. 57-122444, phenol derivatives described in JP-A No. 60-188156, and binderd phenols described in JP-A No. 63-018356.
(2) Paraphenylenediamines described in JP-A-57-122444, paraphenylenediamine derivatives described in JP-A-60-188756, and paraphenylenediamines described in JP-A-63-18356 .
(3) Hydroquinones described in JP-A-57-122444, hydroquinone derivatives described in JP-A-60-188756, and hydroquinones described in JP-A-63-18356.
(4) Sulfur compounds described in JP-A-57-188956 and organic sulfur compounds described in JP-A-63-18356.
(5) Organophosphorus compounds described in JP-A-57-122444 and organophosphorus compounds described in JP-A-63-18356.
(6) Hydroxyanisoles described in JP-A-57-122444.
(7) Piperidine derivatives and oxopiperazine derivatives having a specific skeleton structure described in JP-A-63-018355.
(8) Carotenes, amines, tocopherols, Ni (II) complexes, sulfides and the like described in JP-A-60-18895.

Particularly preferably, the hindered phenols shown below are preferable (hindered phenols indicate phenols having a bulky substituent near the hydroxy group). Dibutylhydroxytoluene,
2,2'-methylenebis (6-tert-butyl-4-methylphenol),
4,4'-butylidenebis (6-tert-butyl-3-methylphenol),
4,4'-thiobis (6-tert-butyl-3-methylphenol),
2,2'-butylidenebis (6-tert-butyl-4-methylphenol),
α-tocophenol, β-tocophenol, 2,2,4-trimethyl-6-hydroxy-7-t-butylchroman,
Pentaerythryltetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate],
2,2′-thiodiethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate],
1,6-hexanediol bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate],
Butylhydroxyanisole, dibutylhydroxyanisole,
Octadecyl-3,5-di-tert-butyl-4-hydroxyhydrocinnamate
1,3,5-trimethyl-2,4,6-tris- (3,5-di-tert-butyl-4-hydroxybenzyl) -benzene (1,3,5-trimethyl-2,4,6-tris -(3,5-di-tert-butyl-4-hydroxybenzyl) -benzene)

Among the above hindered phenols, the following compounds are particularly preferable.
Octadecyl-3,5-di-tert-butyl-4-hydroxyhydrocinnamate
1,3,5-trimethyl-2,4,6-tris- (3,5-di-tert-butyl-4-hydroxybenzyl) -benzene (1,3,5-trimethyl-2,4,6-tris -(3,5-di-tert-butyl-4-hydroxybenzyl) -benzene)

  These compounds are known as antioxidants for rubbers, plastics, oils and the like, and some are available as commercial products.

  In the photoreceptor used in the image forming apparatus of the present invention, the amount of the antioxidant in the surface layer is not particularly limited, but is preferably 0.1 parts by weight or more and 20 parts by weight or less per 100 parts by weight of the binder resin. In other cases, good electrical characteristics cannot be obtained. Particularly preferred is 1 part by weight or more. On the other hand, if the amount is too large, not only the electric characteristics but also the printing durability is caused. Therefore, the amount is preferably 15 parts by weight or less, and more preferably 10 parts by weight or less.

<Electron withdrawing compound>
The photoreceptor preferably has an electron-withdrawing compound. Specifically, a sulfonic acid ester compound, a carboxylic acid ester compound, an organic cyano compound, a nitro compound, an aromatic halogen derivative, and the like are preferable, and particularly preferable. Sulfonic acid ester compounds and organic cyano compounds, and sulfonic acid ester compounds are particularly preferred.

  It is considered that the electron withdrawing ability can be predicted by the value of the LUMO energy level. In particular, the value of the LUMO energy level by structural optimization using semi-empirical molecular orbital calculation using PM3 parameters (hereinafter simply referred to as semi-empirical molecular orbital calculation (PM3)) is −1.0 eV. Compounds that are -3.0 eV are preferred. If the absolute value of the LUMO energy level is smaller than 1.0 eV, the effect of electron withdrawing cannot be expected so much, and if it exceeds 3.0 eV, there is a concern about deterioration of charging. The absolute value of the LUMO energy level is more preferably 1.5 eV or more, still more preferably 1.7 eV or more, and still more preferably 1.9 eV or more. The upper limit is preferably 2.7 eV or less, and more preferably 2.5 eV or less.

  For calculation of the electron-withdrawing compound, PM3 was used as a Hamiltonian. The reason is as follows. In general, electron-withdrawing compounds sometimes use heteroatoms such as sulfur and halogen in addition to carbon, nitrogen, oxygen, and hydrogen. PM3, which defines the parameters of many of these atoms by the least-squares method, is an electron-withdrawing compound. It is considered to be suitable for optimizing the structure of the functional compound.

Specific examples of the electron-withdrawing compound include the following compounds.

<Outermost surface layer>
The charge generation material and the charge transport material may be in any layer, but the outermost surface layer preferably contains fluorine atoms and silicon atoms from the viewpoint of toner transfer and improvement in cleaning properties. . These atoms may be contained in any material including additives, charge generation materials, charge transport materials, and binder resins.

Further, the adhesion of the photoreceptor surface can be detected as surface free energy (synonymous with surface tension). The surface free energy value of the outermost surface layer is preferably in the range of 35 mN / m to 65 mN / m. If it is too low, the toner may flow, and if it is too high, the toner transfer efficiency and cleaning performance may be deteriorated. The lower limit is preferably 40 mN / m or more, and the upper limit is preferably 55 mN / m or less, and more preferably 50 mN / m or less.

[Surface free energy]
The surface free energy will be described below. The adhesion of foreign matter such as residual toner to the surface of the photoreceptor is a category of physical bonding and is caused by an intermolecular force (van der Waals force). Surface free energy (γ) is a phenomenon caused by the intermolecular force on the outermost surface. There are roughly three types of “wetting” of substances. “Adhesion wetting” in which the substance 1 adheres to the substance 2, “extended wetting” in which the substance 1 spreads on the substance 2, and “immersion wetting” in which the substance 1 is immersed or soaked in the substance 2.

  Regarding adhesion wetting, regarding the surface free energy (γ) and wettability, the relationship between the substance 1 and the substance 2 from the Young's formula is as follows.

γ ₁ : Surface free energy of the surface of the substance 1 γ ₂ : Surface free energy of the substance 2 γ ₁₂ : Interfacial free energy of the substance 1 / substance 2 θ ₁₂ : Contact angle of the substance 1 / substance 2

In the above formula (1-1), when it is considered that foreign matter or moisture adheres to the surface of the photosensitive member in the image forming apparatus, the substance 1 may be a photosensitive member and the substance 2 may be a foreign matter.
From formula (1-1), controlling γ ₁ , γ ₂ , and γ ₁₂ is important for surface property control. It is preferably made less wettable surface, in this case, is preferably a direction to increase the theta _12, to increase the surface free energy gamma ₁ of the photosensitive member surface where a "wetting work" of the photosensitive member and the toner, gamma ₂ and it is effective to oblige small gamma _12.

In the electrophotographic cleaning process, by controlling the surface free energy γ ₁ of the photoconductor, it is possible to control the adhesion state of the right side of the equation (1-1) as a result. Further, in terms of durability, toner and other foreign matters are sequentially newly supplied, and γ ₂ can be considered to be constant. On the other hand, the surface free energy γ ₁ of the photoreceptor changes due to durability. As γ ₁ changes by Δγ ₁ , the value on the right side of Equation (1-1) also changes as a result. That is, the state in which foreign matter adheres to the surface of the photoreceptor changes, and as a result, the cleaning performance and the load on the cleaning mechanism change. In other words, by defining the △ gamma _1, the cleaning of the photosensitive member, that is, that can retain the easiness cleaned constant.

Here, with respect to wetting of the solid and liquid, which can measure the contact angle theta ₁₂ directly, as in the photosensitive member and the toner, in the case of solid and solid, not be measured contact angle theta _12. The photoconductor and toner in the present invention are usually solid, and this case applies.

  Noriaki Kitazaki, Toshio Hata et al. In Forkes's theory describing nonpolar intermolecular forces with respect to interfacial free energy (synonymous with interfacial tension) in Japan Adhesion Association paper 8 (3), 131-141 (1972). On the other hand, it is shown that it can be extended to a component due to an intermolecular force having polar or hydrogen bonding properties. By this extended Forkes theory, the surface free energy of each substance can be obtained by 2 to 3 components. Below, the case of adhesion wetness is described as an example for the theory of three components. This theory is based on the following assumptions.

1. Addition rule for surface free energy (γ) γ = γ ^d + γ ^p + γ ^h (1-2)
γ ^d : Dispersion component (nonpolar wetting = adhesion)
γ ^p : Dipole component (wetting due to polarity = adhesion)
γ ^h : hydrogen bonding component (wetting due to hydrogen bonding = adhesion)

By applying this to the ForkeS theory, the interface free energy γ ₁₂ of the two substances is as follows.
Furthermore,

  As a method for measuring the surface free energy, it is possible to use a reagent in which each component of the surface free energy of p, d, and h is known, and measure and calculate the adhesion to the reagent. Specifically, pure water, methylene iodide, α-bromonaphthalene is used as a reagent, and an automatic contact angle meter CA-VP type manufactured by Kyowa Interface Co., Ltd. is used. The surface free energy γ was calculated using the surface free energy analysis software FAMAS manufactured by the same company. In addition to the above, the reagent may be a combination of p, d, and h components in an appropriate combination. In addition to the above, the measuring method can also be performed by measuring by a general method such as the Wilhelmi method (hanging plate method), the Dou Nui method, or the like.

  As described above, there are a plurality of types of “wetting”. However, when the toner adheres to the surface of the photosensitive member and is fused, the toner remaining on the surface of the photosensitive member adheres to the photosensitive member, and cleaning, While the process such as charging is repeated, the toner spreads like a film on the surface of the photoconductor, and the influence of increasing the adhesive strength is great. This corresponds to so-called “adhesion wetness”.

  Similarly, in the case of adhesion of foreign matters such as paper dust, rosin, and talc, the area of the contact surface (hereinafter referred to as “interface”) with the photosensitive member is increased and becomes firmly wet. Furthermore, “wetting” due to foreign matter adhering to the surface of the photoconductor and moisture directly on the surface of the photoconductor is a factor of so-called “high humidity flow” in which the image becomes blurred.

  With respect to these foreign substances, various substances including toner once adhere to the surface of the photoreceptor in the process of forming an electrophotographic image. Of these, so-called “residual toner” and other foreign matters that have not been transferred to the transfer material need to be cleaned, that is, removed within a certain period. The term “fixed period” as used herein refers to the period from the actual time when various substances adhere to the surface of the photoreceptor until the area of the interface with the photoreceptor increases due to diffusion and / or further adhesion. Refers to the period of state.

  Characteristics related to cleaning within the above-mentioned range, that is, “adhesion wetting” of foreign matters adhering to the photosensitive member, and “extended wetting”, which are related to practical cleaning characteristics and the life of the cleaning device or the photosensitive member. , Will be a big factor. Therefore, the present inventors have considered that it is effective to define the surface free energy γ of the photoreceptor, and have intensively studied and found that an electrophotographic image with high image quality and high durability can be obtained. In particular, the substance 2, that is, the above-described foreign matter, may be various types such as toner, paper powder, moisture, silicone oil, and the like.

In the present invention, the surface free energy γ ₁ is defined on the surface of the photoconductor of the substance 1 on the side to be adhered. Further, in the above material 2 is durable, while those fed from time to time, the photoreceptor surface is a material 1 by the durability, the gamma ₁ is changed. Per To consider the durability of the electrophotographic apparatus for forming an image, it is important to control the variation △ gamma _1.

[control]
In order to stably obtain a high-quality image, the cleaning property of the photosensitive member, in particular, the load for cleaning the photosensitive member is controlled. By defining the value of the surface free energy γ of the photosensitive member in the range of 35 to 65 mN / m, more preferably 40 to 60 mN / m, good cleaning properties can be obtained with a low load. In addition, by using the amount Δγ that varies with durability within a range of 25 mN / m, preferably within 15 mN / m, fluctuations in the load on both the photoconductor and the cleaning device are suppressed, and the cleaning characteristics are stable over a long period of time. Can be made.

  In particular, a protective layer may be provided on the outermost surface layer of the photoreceptor in order to prevent the photosensitive layer from being worn out or to prevent or reduce deterioration of the photosensitive layer due to a discharge substance generated from a charger or the like. The protective layer is formed by containing a conductive material in a suitable binder resin, or a copolymer using a compound having a charge transporting ability such as a triphenylamine skeleton as described in JP-A-9-190004 Can be used. Examples of the conductive material include aromatic amino compounds such as TPD (N, N′-diphenyl-N, N′-bis- (m-tolyl) benzidine), antimony oxide, indium oxide, tin oxide, titanium oxide, and tin oxide. -Metal oxides such as antimony oxide, aluminum oxide, and zinc oxide can be used, but are not limited thereto.

  As the binder resin used for the protective layer, known resins such as polyamide resin, polyurethane resin, polyester resin, epoxy resin, polyketone resin, polycarbonate resin, polyvinyl ketone resin, polystyrene resin, polyacrylamide resin, and siloxane resin can be used. Further, a copolymer of the above resin with a skeleton having a charge transporting ability such as a triphenylamine skeleton as described in JP-A-9-190004 can also be used.

The protective layer is preferably configured to have an electric resistance of 10 ⁹ to 10 ¹⁴ Ω · cm. When the electrical resistance is higher than 10 ¹⁴ Ω · cm, the residual potential is increased, resulting in an image with much fog. On the other hand, when the electrical resistance is lower than 10 ⁹ Ω · cm, the image is blurred and the resolution is reduced. In addition, the protective layer must be configured so as not to substantially impede transmission of light irradiated for image exposure.

  In addition, fluorine resin, silicone resin, polyethylene resin, polystyrene resin, etc. are used for the surface layer for the purpose of reducing frictional resistance and abrasion on the surface of the photoconductor and increasing the transfer efficiency of the toner from the photoconductor to the transfer belt and paper. May be included. Moreover, the particle | grains which consist of these resin, and the particle | grains of an inorganic compound may be included.

<Layer formation method>
Each layer constituting the photoreceptor is formed by sequentially applying a coating solution containing the material constituting each layer on the support using a known coating method and repeating the coating and drying process for each layer. The

  In the case of the charge transport layer of the single layer type photoreceptor and the multilayer type photoreceptor, the coating solution for forming the layer is usually used in a solid content concentration of 5 to 40% by mass, but 10 to 35% by mass. It is preferable to use in the range. Moreover, although the viscosity of this coating liquid is normally used in the range of 10-500 mPa * s, it is preferable to set it as the range of 50-400 mPa * s.

  In the case of the charge generating layer of the multilayer photoreceptor, the solid content is usually used in the range of 0.1 to 15% by mass, but more preferably in the range of 1 to 10% by mass. Although the viscosity of a coating liquid is normally used in the range of 0.01-20 mPa * s, it is more preferable to be used in the range of 0.1-10 mPa * s.

  Examples of the coating method include a dip coating method, a spray coating method, a spinner coating method, a bead coating method, a wire bar coating method, a blade coating method, a roller coating method, an air knife coating method, and a curtain coating method. Other known coating methods can also be used.

  The coating solution is preferably dried by touching at room temperature and then heating and drying in a temperature range of 30 to 200 ° C. for 1 minute to 2 hours with no air or air. The heating temperature may be constant or may be changed while drying.

<Image forming apparatus>
The image forming method using the image forming apparatus 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 to perform an image forming method. In FIG. 1, the toner 16 incorporated in the toner hopper 17 is forcibly brought to a roller-like sponge roller (toner supply auxiliary member) 14 by the stirring blade 15, and the toner is supplied to the sponge roller 14. Then, the toner taken in by the sponge roller 14 is carried to the toner conveying member 12 by the rotation of the sponge roller 14 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 the steel elastic blade (toner layer thickness regulating member) 13 and is triboelectrically charged. Thereafter, the toner is conveyed to the surface of the electrostatic latent image carrier 11 in contact with the toner conveying member 12, 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.

  Since the toner used in the image forming apparatus of the present invention has a sharp charge amount distribution, there is very little contamination (toner scattering) in the image forming apparatus caused by poorly charged toner. 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 toner used in the image forming apparatus of the present invention has a sharp charge amount distribution, so that the developability is very good, and toner particles that accumulate without being developed are very few. The effect is exhibited in an image forming apparatus with high consumption speed. Specifically, a toner used for an image forming apparatus that satisfies the following formula (G) is preferable in order to sufficiently exhibit the above-described effects of the present invention.

(G) Guaranteed lifetime number of sheets (sheets) x printing rate ≧ 400 (sheets) of the developer filled with developer
In the formula (G), the “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 toner used in the image forming apparatus of the present invention has a very sharp particle size distribution, the reproducibility of the latent image 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.

  Next, the configuration around the electrophotographic process of the image forming apparatus of the present invention will be described with reference to FIG. However, the embodiment is not limited to the following description, and can be arbitrarily modified without departing from the gist of the present invention.

  As shown in FIG. 2, the image forming apparatus includes an electrophotographic photoreceptor 1, a charging device 2, an exposure device 3, and a developing device 4, and further, a transfer device 5, a cleaning device 6 and a fixing device as necessary. A device 7 is provided.

  The electrophotographic photosensitive member 1 is not particularly limited as long as it is an electrophotographic photosensitive member used in the above-described image forming apparatus of the present invention. In FIG. 2, as an example, the surface of the cylindrical conductive support is described above. 2 shows a drum-shaped photoreceptor on which a photosensitive layer is formed. A charging device 2, an exposure device 3, a developing device 4, a transfer device 5, and a cleaning device 6 are arranged along the outer peripheral surface of the electrophotographic photoreceptor 1.

  The charging device 2 charges the electrophotographic photosensitive member 1 and uniformly charges the surface of the electrophotographic photosensitive member 1 to a predetermined potential. In FIG. 2, a roller-type charging device (charging roller) is shown as an example of the charging device 2, but other corona charging devices such as corotrons and scorotrons, contact-type charging devices such as charging brushes, and the like are often used.

  In many cases, the electrophotographic photosensitive member 1 and the charging device 2 are designed to be removable from the main body of the image forming apparatus as a cartridge including both of them (hereinafter, appropriately referred to as a photosensitive cartridge). For example, when the electrophotographic photoreceptor 1 or the charging device 2 deteriorates, the photoreceptor cartridge can be removed from the image forming apparatus main body, and another new photosensitive cartridge can be mounted on the image forming apparatus main body. ing. Also, the toner described later is often stored in the toner cartridge and designed to be removable from the main body of the image forming apparatus. When the toner in the used toner cartridge runs out, this toner cartridge is removed. It can be removed from the main body of the image forming apparatus and another new toner cartridge can be mounted. Further, a cartridge equipped with all of the electrophotographic photosensitive member 1, the charging device 2, and the toner may be used.

  The type of the exposure apparatus 3 is not particularly limited as long as it can expose the electrophotographic photoreceptor 1 to form an electrostatic latent image on the photosensitive surface of the electrophotographic photoreceptor 1. Specific examples include halogen lamps, fluorescent lamps, lasers such as semiconductor lasers and He—Ne lasers, LEDs, and the like. Further, exposure may be performed by a photoreceptor internal exposure method. The light at the time of exposure is arbitrary. For example, the exposure is performed with monochromatic light having a wavelength of 700 nm to 850 nm, monochromatic light having a wavelength slightly shorter than 600 nm to 700 nm, or monochromatic light having a short wavelength of 300 nm to 500 nm. Just do it.

  In particular, in the case of an electrophotographic photoreceptor using only a phthalocyanine compound having a specific crystal type that can be used in the present invention as a charge generation material, it is preferable to use monochromatic light having a wavelength of 700 nm to 850 nm, and an azo compound is used in combination. In the case of the electrophotographic photoreceptor to be used, it is preferable to use monochromatic light having a wavelength of 700 nm or less. In the case of an electrophotographic photoreceptor using an azo compound, monochromatic light having a wavelength of 500 nm or less may have sufficient sensitivity as a light input light source, and therefore monochromatic light having a wavelength of 380 nm to 500 nm is used as a light input light source. This is particularly preferred.

  The type of the developing device 4 is not particularly limited, and any device such as a dry development method such as cascade development, one-component conductive toner development, two-component magnetic brush development, or a wet development method can be used. In FIG. 2, the developing device 4 includes a developing tank 41, an agitator 42, a supply roller 43, a developing roller 44, and a regulating member 45, and has a configuration in which toner T is stored inside the developing tank 41. . Further, a replenishing device (not shown) for replenishing the toner T may be attached to the developing device 4 as necessary. This replenishing device is configured to be able to replenish toner T from a container such as a bottle or a cartridge.

The supply roller 43 is formed from a conductive sponge or the like. The developing roller 44 includes a metal roll such as iron, stainless steel, aluminum, or nickel, or a resin roll obtained by coating such a metal roll with a silicone resin, a urethane resin, a fluororesin, or the like. The surface of the developing roller 44 may be smoothed or roughened as necessary.
The developing roller 44 is disposed between the electrophotographic photosensitive member 1 and the supply roller 43 and is in contact with the electrophotographic photosensitive member 1 and the supply roller 43, respectively. The supply roller 43 and the developing roller 44 are rotated by a rotation drive mechanism (not shown). The supply roller 43 carries the stored toner T and supplies it to the developing roller 44. The developing roller 44 carries the toner T supplied by the supply roller 43 and contacts the surface of the electrophotographic photoreceptor 1.

  The regulating member 45 is formed of a resin blade such as a silicone resin or a urethane resin, a metal blade such as stainless steel, aluminum, copper, brass, phosphor bronze, or a blade obtained by coating such a metal blade with a resin. The regulating member 45 contacts the developing roller 44 and is pressed against the developing roller 44 side with a predetermined force by a spring or the like (a general blade linear pressure is 5 to 500 g / cm). If necessary, the regulating member 45 may be provided with a function of imparting charging to the toner T by frictional charging with the toner T.

  The agitator 42 is rotated by a rotation driving mechanism, and agitates the toner T and conveys the toner T to the supply roller 43 side. A plurality of agitators 42 may be provided with different blade shapes and sizes.

  As the toner T, a toner having a small particle size with a volume median diameter (Dv50) of 4.0 μm to 7.0 μm and having the specific particle size distribution described above is used. Further, the toner particles can be used in various shapes from a shape close to a sphere to a shape outside the sphere on the potato. The polymerized toner is excellent in charging uniformity and transferability and is suitably used for high image quality.

  The type of the transfer device 5 is not particularly limited, and an apparatus using an arbitrary system such as an electrostatic transfer method such as corona transfer, roller transfer, or belt transfer, a pressure transfer method, or an adhesive transfer method can be used. . Here, it is assumed that the transfer device 5 includes a transfer charger, a transfer roller, a transfer belt, and the like disposed so as to face the electrophotographic photoreceptor 1. The transfer device 5 applies a predetermined voltage value (transfer voltage) having a polarity opposite to the charging potential of the toner T, and transfers the toner image formed on the electrophotographic photosensitive member 1 to a recording paper (paper, medium) P. Is.

  There is no restriction | limiting in particular about the cleaning apparatus 6, Arbitrary cleaning apparatuses, such as a brush cleaner, a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, a blade cleaner, can be used. The cleaning device 6 is for scraping off residual toner adhering to the photoreceptor 1 with a cleaning member and collecting the residual toner. However, when there is little or almost no toner remaining on the surface of the photoreceptor, the cleaning device 6 may be omitted.

  The fixing device 7 includes an upper fixing member (pressure roller) 71 and a lower fixing member (fixing roller) 72, and a heating device 73 is provided inside the fixing member 71 or 72. FIG. 2 shows an example in which a heating device 73 is provided inside the upper fixing member 71. The upper and lower fixing members 71 and 72 include a fixing roll in which a metal base tube made of stainless steel, aluminum or the like is coated with silicone rubber, a fixing roll in which Teflon (registered trademark) resin is coated, a fixing sheet, or the like. A member can be used. Further, the fixing members 71 and 72 may be configured to supply a release agent such as silicone oil in order to improve the releasability, or may be configured to forcibly apply pressure to each other by a spring or the like.

  When the toner transferred onto the recording paper P passes between the upper fixing member 71 and the lower fixing member 72 heated to a predetermined temperature, the toner is heated to a molten state and cooled after passing through the recording paper. Toner is fixed on P. The type of the fixing device is not particularly limited, and a fixing device of an arbitrary system such as a heat roller fixing method, a flash fixing method, an oven fixing method, a pressure fixing method, or the like can be provided.

  In the electrophotographic apparatus configured as described above, an image is recorded as follows. That is, first, the surface (photosensitive surface) of the photoreceptor 1 is charged to a predetermined potential (for example, −600 V) by the charging device 2. At this time, charging may be performed with a DC voltage, or charging may be performed by superimposing an AC voltage on the DC voltage. Subsequently, the photosensitive surface of the charged photoreceptor 1 is exposed by the exposure device 3 according to the image to be recorded, and an electrostatic latent image is formed on the photosensitive surface. The developing device 4 develops the electrostatic latent image formed on the photosensitive surface of the photoreceptor 1.

  The developing device 4 thins the toner T supplied by the supply roller 43 with a regulating member (developing blade) 45 and has a predetermined polarity (here, the same polarity as the charging potential of the photosensitive member 1) and the negative polarity. ) And is carried while being carried on the developing roller 44 and brought into contact with the surface of the photoreceptor 1. When the charged toner T carried on the developing roller 44 comes into contact with the surface of the photoreceptor 1, a toner image corresponding to the electrostatic latent image is formed on the photosensitive surface of the photoreceptor 1. This toner image is transferred onto the recording paper P by the transfer device 5. Thereafter, the toner remaining on the photosensitive surface of the photoreceptor 1 without being transferred is removed by the cleaning device 6.

  After the transfer of the toner image onto the recording paper P, the final image is obtained by passing the fixing device 7 and thermally fixing the toner image onto the recording paper P.

  In addition to the above-described configuration, the image forming apparatus may be configured to perform, for example, a static elimination process. The neutralization step is a step of neutralizing the electrophotographic photosensitive member by exposing the electrophotographic photosensitive member, and a fluorescent lamp, an LED, or the like is used as the neutralizing device. In addition, the light used in the static elimination process is often light having an exposure energy that is at least three times that of the exposure light.

  The image forming apparatus may be further modified. For example, the image forming apparatus may be configured to perform a pre-exposure process, an auxiliary charging process, or the like, or may be configured to perform offset printing. A full-color tandem system configuration using toner may be used.

  In addition, by using the above-mentioned photoconductor used in the image forming apparatus of the present invention, which has excellent physical and electrical surface properties, and the above-mentioned toner together, the image characteristics are excellent, the image stain is small, and the transfer efficiency. A high system can be constructed.

  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. Unless otherwise specified, in the following examples, “part” means “part by weight”, and “%” means “mass%”.

<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
-Permeability: Transmission-Shape: True 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
・ Transparency: Absorption ・ Shape: Non-spherical shape ・ 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 is Bocman Coulter's Multisizer III (aperture diameter 100 μm) (hereinafter abbreviated as “Multisizer”), the dispersion medium is Isoton II, and the above-mentioned “ The “toner dispersion liquid” or “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 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 measuring device multisizer, and the upper limit particle size of 3.56 μm is a prescribed channel value in the measuring device multisizer. In the present invention, an area having a particle size of 2.00 μm or more and 3.56 μm or less is recognized as a fine powder area.

  The measurement particle size range is from 2.00 μm to 64.00 μm, and this range is discretized into 256 divisions so as to be equally spaced on a logarithmic scale. To 3.56 μm, the ratio of the particle size component was calculated on the basis of the number and was defined as “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” in the present invention is defined as follows.
[Number variation coefficient] = 100 × [Standard deviation of particle distribution based on number] / [Number average particle diameter]

  In the present invention, the standard deviation of the number-based particle distribution and the number average particle diameter were measured using Multisizer III according to the method of measuring the volume median diameter (Dv50). The measurement particle range is from 2.00 μm to 64.00 μm, and this range is discretized into 256 divisions at equal intervals in the logarithmic memory, and the number-based particle distribution based on the statistical values based on the number-based number. The standard deviation and the number average particle diameter were determined, and the number variation coefficient was calculated from the above formula.

<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.

<Measurement method of charge amount distribution (standard deviation of charge amount)>
0.8 g of toner / carrier (19.2 g of ferrite carrier manufactured by Powdertech Co., Ltd.) was placed in a glass sample bottle and stirred for 30 minutes at 250 rpm using a reciprocating shaker NR-1 (manufactured by Taitec Corporation). The stirred toner / carrier mixture was subjected to charge amount distribution measurement using an E-Spart charge amount distribution measuring apparatus (manufactured by Hosokawa Micron Corporation). The value obtained by dividing the charge amount of each particle by the particle diameter is obtained from the obtained data (the range from −16.197 C / μm to +16.197 C / μm is discretized into 128 divisions every 0.2551 C / μm). The standard deviation of the 3000 particle measurement results was obtained and used as the standard deviation of the charge amount.

<Method of live-action evaluation>
[Live-action evaluation 1]
Using 80 g of toner as a photoreceptor, “Photoreceptor 2” described later, non-magnetic one-component development system, roller charging, rubber development roller contact development system, process speed (development speed) of 164 mm / second, belt transfer system, blade With a drum cleaning method, the cartridge was loaded into a cartridge of a 600 dpi machine having a guaranteed life of 30,000 sheets at a 5% printing rate, and 50 charts of 1% printing rate were continuously printed.

[Live-action evaluation 2]
Using 200 g of toner as a photoreceptor, “Photoreceptor 2” to be described later, non-magnetic one-component development system, roller charging, rubber development roller contact development system, process speed (development speed) 100 mm / second, belt transfer system, blade Using a drum cleaning method, the cartridge was loaded into a 600 dpi machine cartridge with a guaranteed life of 8000 sheets at a 5% printing rate, and a 5% printing rate chart was continuously printed until a toner out indication was displayed.

<Dirt>
In “actual evaluation 1” using an electrophotographic photosensitive member 2 described later, the smudges on the image after printing 50 sheets were visually observed and judged according to the following criteria.
◎: No dirt at all ○: Slightly dirty but usable level Δ: Partly slightly dirty ×: Partly or entirely clear dirt can be confirmed.

<Afterimage (Ghost)>
In “actual evaluation 2” using an electrophotographic photosensitive member 2 to be described later, a solid image is printed, and the image density of the leading end portion and the image density of the portion printed after two rotations of the developing roller from there are respectively X-write. 938 (manufactured by X-Rite Co., Ltd.), and the ratio (%) of the image density after two rounds to the tip portion was determined.
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%)

<Scratch (solid followability)>
In “actual evaluation 2” using an electrophotographic photosensitive member 2 described later, a solid image is printed, and the image density of the front end portion and the image density of the rear end portion are respectively set by X-rite 938 (manufactured by X-Rite). Measurement was made to determine the ratio (%) of the image density at the rear end to the front end.
A: No problem at all (80% or more)
○: Slightly thin rear end but usable level (70% or more and less than 80%)
X: Level at which rear end is considerably thin (less than 70%)

<Cleanability>
In “actual evaluation 2” using the electrophotographic photosensitive member 2 described later, the smear of the image after printing 8000 sheets was visually observed to confirm whether the image was smudged due to poor drum cleaning.
○: No dirt △: Partly slightly dirty x: Partly or entirely dirty.

Toner production example 1

<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-value 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 stirred for 10 minutes using a homomixer (Mark II f model manufactured by Tokushu Kika Kogyo Co., Ltd.). did.

  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)
Butyl acrylate 23.2 parts Acrylic acid 1.5 parts Hexanediol diacrylate 0.7 parts Trichlorobromomethane 1.0 part

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

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

[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)
Butyl acrylate 7.5 parts Acrylic acid 0.5 part Trichlorobromomethane 0.5 part

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

[Initiator aqueous solution]
8% by mass aqueous hydrogen peroxide solution 18.9 parts 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 A>
Carbon black (Mitsubishi Chemical Co., Ltd.) manufactured by a furnace method with a 300 L internal volume equipped with a stirrer (propeller blade) and a toluene extract having an ultraviolet absorbance of 0.02 and a true density of 1.8 g / cm ³ Mitsubishi Carbon Black MA100S) 20 parts (40 kg), 20% DBS aqueous solution 1 part, nonionic surfactant (manufactured by Kao Corp., Emulgen 120) 4 parts, ion-exchanged water 75 parts with an electric conductivity of 2 μS / cm In addition, it was predispersed to obtain a pigment premix solution. The volume average diameter (Mv) of carbon black in the dispersion after pigment premixing measured with Nanotrac was 90 μm.

The pigment premix solution was supplied as a raw material slurry to a wet bead mill and subjected to one-pass dispersion. 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 100 μm (true density of 6.0 g / cm ³ ) were used as a dispersion 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 To obtain a black colorant dispersion A. The volume average diameter (Mv) of the colorant dispersion A measured with Nanotrac was 150 nm, and the solid content concentration was 24.2% by mass.

<Manufacture of toner mother particle A>
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 colorant dispersion A as solids 6 parts 20% DBS aqueous solution as colorants solids In the core material agglomeration process, 0.2 parts 20% DBS aqueous solution as solids in the rounding process, 6 parts solids

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid A1 and a 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, with stirring at 250 ° C. at an internal temperature of 7 ° C., 0.52 parts of FeSO ₄ .7H ₂ O as a 5% by mass aqueous solution of ferrous sulfate was added over 5 minutes, and then colorant dispersion A Was added uniformly over 5 minutes, and the mixture was uniformly mixed at an internal temperature of 7 ° C., and a 0.5% by mass aqueous solution of aluminum sulfate was added dropwise over 8 minutes under the same conditions (solid content relative to resin solid content). 0.10 parts). Thereafter, the internal temperature was raised to 54.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.32 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was added over 3 minutes while maintaining the internal temperature of 54.0 ° C and the rotation speed 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 (solid content) 6 parts) was added over 10 minutes, and then the temperature was raised to 81 ° C. over 30 minutes, and heating and stirring were continued under these conditions until the average circularity reached 0.943. Thereafter, the mixture was cooled to 30 ° C. over 20 minutes to obtain a slurry.

Washing step The obtained slurry was extracted and suction filtered with an aspirator using 5 types C (Toyo Filter Paper No. 5C) filter paper. 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 step The solid material obtained here was spread on a stainless steel bat so that the height was 20 mm, and dried in a blow dryer set at 40 ° C. for 48 hours to obtain toner mother particles A.

<Manufacture of toner A>
External Addition Step To 250 g of the obtained toner base particles A, 1.55 g of H2000 silica manufactured by Clariant and 0.62 g of SMT150IB titania fine powder manufactured by Teika are mixed as an external additive, and a sample mill (manufactured by Kyoritsu Riko) is used. The toner A was obtained by mixing at 6000 rpm for 1 minute and sieving with 150 mesh.

Analyzing Step The “volume median diameter (Dv50)” measured using the toner A multisizer obtained here is 5.54 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 3.83%, the average circularity was 0.943, and the number variation coefficient was 18.6%.

Toner production example 2
<Manufacture of toner mother particle B>
The “core material aggregation process”, “shell coating process”, and “circularization process” in the aggregation process (core material aggregation process / shell coating process), circularization process, cleaning process, and drying process of “Manufacture of toner base particles A” The toner mother particles B were obtained in the same manner as in “Production of toner mother particles A” in Example 1 except that “” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid A1 and a 20% DBS aqueous solution were 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 Dispersion A 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 under the same conditions (based on the resin solid content). Solid content 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 5.86 μm.

○ Shell coating step 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 rotation 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 rotation speed of the aggregation process), and then a 20% DBS aqueous solution (as solid content) 6 parts) was added over 10 minutes, and then the temperature was raised to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.942. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacture of toner B>
Thereafter, the toner B was prepared in the same manner as in “Production of Toner A” 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.

Analyzing Step The volume median diameter (Dv50) measured by using the multisizer of toner B obtained here is 5.97 μm, and “the number% of toner having a particle diameter of 2.00 μm to 3.56 μm (Dns ) ”Was 2.53%, the average circularity was 0.943, and the number variation coefficient was 18.4%.

Toner production example 3
<Manufacture of toner mother particles C>
The “core material aggregation process”, “shell coating process”, and “circularization process” in the aggregation process (core material aggregation process / shell coating process), circularization process, cleaning process, and drying process of “Manufacture of toner base particles A” The toner base particles C were obtained in the same manner as in “Production of toner base particles A” in Example 1 except that “” was changed as follows.

○ Core material agglomeration step Polymer primary particle dispersion in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrating device and raw material / auxiliary charging device A1 and a 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 7 ° C. and adding stirring at 250 rpm, 0.52 parts of FeSO ₄ · 7H ₂ O as a 5 mass% aqueous solution of ferrous sulfate was added over 5 minutes, and then the colorant was dispersed. Liquid A 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 under the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 57.0 ° C. while maintaining the rotational speed of 250 rpm, and the volume median diameter (Dv50) was measured using a multisizer to grow it to 6.72 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was added over 3 minutes while maintaining the internal temperature at 57.0 ° 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 (solid content) 6 parts) was added over 10 minutes, and then heated to 87 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.941. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacture of toner C>
Thereafter, the toner C was prepared in the same manner as in “Production of toner A” except that the amount of H2000 silica as an external additive was changed to 1.25 g and the amount of SMT150IB titania fine powder was changed to 0.50 g. Got.

Analyzing Step The volume median diameter (Dv50) measured by using the multisizer of toner C obtained here is 6.75 μm, and “the number% of toner having a particle diameter of 2.00 μm to 3.56 μm (Dns ) ”Was 1.83%, the average circularity was 0.942, and the number variation coefficient was 18.7%.

Toner production example 4
<Manufacture of toner mother particles D>
The “core material aggregation process”, “shell coating process”, and “circularization process” in the aggregation process (core material aggregation process / shell coating process), circularization process, cleaning process, and drying process of “Manufacture of toner base particles A” The toner mother particles D were obtained in the same manner as in “Production of toner mother particles A” in Example 1 except that “A” was changed as follows.

○ Core material agglomeration step Polymer primary particle dispersion in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrating device and raw material / auxiliary charging device A1 and a 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 21 ° C. and continuing stirring at 250 rpm, 0.52 parts of FeSO ₄ .7H ₂ O as a 5 mass% aqueous solution of ferrous sulfate was added over 5 minutes, and then the colorant was dispersed. Liquid A 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 under the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 54.0 ° C. while maintaining the rotational speed of 250 rpm, the volume median diameter (Dv50) was measured using a multisizer, and grown to 5.34 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was added over 3 minutes while maintaining the internal temperature of 54.0 ° C and the rotation speed of 250 rpm, and the state was maintained for 60 minutes.

○ Circularization process Subsequently, the rotation speed was reduced to 220 rpm (circumferential speed 2.28 m / sec at the tip of the stirring blade, stirring speed reduced by 12% with respect to the aggregation process rotation speed), and then 20% DBS aqueous solution (as solid content) 6 parts) was added over 10 minutes, then the temperature was raised to 81 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.942. Then, it cooled to 30 degreeC over 20 minutes, and obtained the slurry.

<Manufacture of toner D>
Thereafter, the toner D was obtained by the same operation of the external addition process as that in “Production of Toner A” in Example 1.

Analyzing Step The volume median diameter (Dv50) of the toner D obtained here measured using a multisizer is 5.48 μm, and “the number% of toner having a particle size of 2.00 μm to 3.56 μm (Dns ) "Was 4.51%, the average circularity was 0.943, and the number variation coefficient was 20.4%.

Toner production example 5
<Manufacture of toner mother particles E>
The “core material aggregation process”, “shell coating process”, and “circularization process” in the aggregation process (core material aggregation process / shell coating process), circularization process, cleaning process, and drying process of “Manufacture of toner base particles A” The toner mother particles E were obtained in the same manner as in “Production of toner mother particles A” in Example 1 except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid A1 and a 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 21 ° C. and continuing stirring at 250 rpm, 0.52 parts of FeSO ₄ .7H ₂ O as a 5 mass% aqueous solution of ferrous sulfate was added over 5 minutes, and then the colorant was dispersed. Liquid A 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 under 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 5.86 μm.

○ Shell coating step 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 220 rpm (a peripheral speed of 2.28 m / second at the tip of the stirring blade, a stirring speed reduced by 12% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (solid content) 6 parts) was added over 10 minutes, and then the temperature was raised to 84 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.941. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacture of toner E>
Thereafter, the toner E was changed in the same manner as in “Production of Toner A” 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.

Analyzing Step The volume median diameter (Dv50) measured using a multisizer of the developing toner E obtained here is 5.93 μm, and “the number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 3.62%, the average circularity was 0.942, and the number variation coefficient was 20.1%.

Toner Production Example 6
<Manufacture of toner mother particles F>
The “core material aggregation process”, “shell coating process”, and “circularization process” in the aggregation process (core material aggregation process / shell coating process), circularization process, cleaning process, and drying process of “Manufacture of toner base particles A” The toner mother particles F were obtained in the same manner as in “Production of toner mother particles A” in Example 1 except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid A1 and a 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 21 ° C. and continuing stirring at 250 rpm, 0.52 parts of FeSO ₄ .7H ₂ O as a 5 mass% aqueous solution of ferrous sulfate was added over 5 minutes, and then the colorant was dispersed. Liquid A 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 under the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 57.0 ° C. while maintaining the rotational speed of 250 rpm, and the volume median diameter (Dv50) was measured using a multisizer to grow it to 6.76 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was added over 3 minutes while maintaining the internal temperature at 57.0 ° 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 220 rpm (a peripheral speed of 2.28 m / second at the tip of the stirring blade, a stirring speed reduced by 12% with respect to the rotational speed of the aggregation process), and then a 20% DBS aqueous solution (solid content) 6 parts) was added over 10 minutes, and then heated to 87 ° C. over 30 minutes, and heating and stirring were continued until the average circularity reached 0.941. Thereafter, it was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacture of toner F>
Thereafter, the amount of H2000 silica as an external additive was changed to 1.25 g, and the amount of SMT150IB titania fine powder was changed to 0.50 g. Got.

Analyzing Step The volume median diameter (Dv50) measured by using the multisizer of toner F obtained here is 6.77 μm, and “the number% of toner having a particle size of 2.00 μm to 3.56 μm (Dns ) ”Was 2.48%, the average circularity was 0.942, and the number variation coefficient was 21.1%.

Toner Comparative Production Example 1
<Manufacture of toner mother particle G>
The “core material aggregation process”, “shell coating process”, and “circularization process” in the aggregation process (core material aggregation process / shell coating process), circularization process, cleaning process, and drying process of “Manufacture of toner base particles A” The toner mother particles G were obtained in the same manner as in “Production of toner mother particles A” in Example 1 except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid A1 and a 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 7 ° C. for 5 minutes. Subsequently, while maintaining the internal temperature at 21 ° C. and continuously stirring at 250 rpm, 0.52 parts of FeSO ₄ .7H ₂ O as a 5 mass% aqueous solution of ferrous sulfate was added all at once in 5 minutes, and then the colorant was dispersed. Liquid A was added all at once in 5 minutes, mixed uniformly at an internal temperature of 7 ° C., and 0.5 mass% aqueous aluminum sulfate solution was added in 8 seconds under the same conditions (solid to resin solids). Min is 0.10 parts). Thereafter, the internal temperature was raised to 57.0 ° C. while maintaining the rotational speed of 250 rpm, and the volume median diameter (Dv50) was measured using a multisizer to grow to 6.85 μm.

○ Shell coating step Thereafter, the polymer primary particle dispersion A2 was added all at once in 3 minutes while maintaining the internal temperature at 57.0 ° C. and the rotational speed of 250 rpm, and held as it was for 60 minutes.

○ Circularization process Subsequently, 20% DBS aqueous solution (6 parts as solid content) was maintained for 10 minutes while maintaining the rotational speed at 250 rpm (peripheral speed 2.59 m / sec at the tip of the stirring blade, the same stirring speed as the aggregation process rotational speed). Then, the temperature was raised to 87 ° C. over 30 minutes, and heating and stirring were continued until the average circularity became 0.942. Thereafter, the mixture was cooled to 30 ° C. over 20 minutes to obtain a slurry.

<Manufacture of toner G>
Thereafter, the toner G was prepared in the same manner as in “Production of Toner A” except that the amount of H2000 silica as an external additive was changed to 1.25 g and the amount of SMT150IB titania fine powder was changed to 0.50 g. Got.

○ Analyzing step The volume median diameter (Dv50) measured using a multisizer of the developing toner G obtained here is 6.79 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 4.52%, the average circularity was 0.943, and the number variation coefficient was 24.5%.

Examples 1 to 6, Comparative Example 1
Using the toners A to G, the photoconductor 2 described later was used as the photoconductor, and “dirt” was evaluated by the method of “actual evaluation 1”. The results are shown in Table 2 below.

  As is apparent from the results in Table 2 above, the toners A to F satisfying the expression of the requirement (3) in the present invention were actually manufactured by the manufacturing methods shown in the toner manufacturing examples 1 to 6. All of the toners A to F satisfying all the requirements (1) to (3) of the present invention had a sufficiently small standard deviation in charge amount and a sharp charge amount distribution. Further, in the actual photograph evaluation 1 combined with the photoconductor 2 described later, there was no dirt at all, or there was a slight dirt, but it was at a usable level (Example 3 and Example 6).

  On the other hand, the toner G that does not satisfy the expression of requirement (3) has a large standard deviation of the charge amount, and the charge amount distribution is not sharp. In addition, even in the live-action evaluation 1 combined with the photoconductor 2 described later, overall contamination was clearly confirmed (Comparative Example 1).

Toner production example 7
<Preparation of wax / long-chain polymerizable monomer dispersion H1>
Paraffin wax (HNP-9 manufactured by Nippon Seiki Co., Ltd., surface tension 23.5 mN / m, thermal characteristics: melting point peak temperature 82 ° C., melting peak half width 8.2 ° C., crystallization temperature 66 ° C., crystallization peak half width 13 27 ° C. (540 g), 2.8 parts stearyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 1.9 parts 20% DBS aqueous solution, 68.3 parts demineralized water to 90 ° C. and heated to a homomixer (special The mixture was stirred for 10 minutes using Mark II f model manufactured by Meika Kogyo Co., Ltd.

  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 H1 (emulsion solid content concentration = 30.2 mass%).

<Preparation of polymer primary particle dispersion H1>
In a reactor (inner volume 21 L, inner diameter 250 mm, height 420 mm) equipped with a stirrer (three blades), a heating / cooling device, and each raw material / auxiliary charging device, the above wax / long-chain polymerizable monomer dispersion 35.6 parts (712.12 g) of H1 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)
Butyl acrylate 23.2 parts Acrylic acid 1.5 parts Hexanediol diacrylate 0.7 parts Trichlorobromomethane 1.0 part

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

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

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

  After completion of the polymerization reaction, the mixture was cooled to obtain a milky white polymer primary particle dispersion H1. The volume average diameter (Mv) measured using Nanotrac was 265 nm, and the solid content concentration was 22.3 mass%.

<Preparation of silicone wax dispersion H2>
Alkyl-modified silicone wax (thermal characteristics: melting point peak temperature 77 ° C., heat of fusion 97 J / g, melting peak half width 10.9 ° C., crystallization temperature 61 ° C., crystallization peak half width 17.0 ° C.) 27 parts (540 g) Then, 1.9 parts of a 20% DBS aqueous solution and 71.1 parts of demineralized water were placed in a 3 L stainless steel container, heated to 90 ° C., and stirred for 10 minutes with a homomixer (Mark II f model manufactured by Tokushu Kika Kogyo Co., Ltd.). Next, this dispersion was heated to 99 ° C., and circulation emulsification was started under a pressure of 45 MPa using a homogenizer (manufactured by Gorin Co., Ltd., 15-M-8PA type). ) To 240 nm to prepare a silicone wax dispersion H2 (emulsion solid content concentration = 27.3%).

<Preparation of polymer primary particle dispersion H2>
23.3 parts (466 g) of silicone wax dispersion H2 was added to a reactor (inner volume 21 L, inner diameter 250 mm, height 420 mm) equipped with a stirrer (three blades), a heating / cooling device, and each raw material / auxiliary charging device. ), 1.0 part of 20% DBS aqueous solution and 324 parts of demineralized water were added, the temperature was raised to 90 ° C. under a nitrogen stream, and 3.2 parts of 8% aqueous hydrogen peroxide solution, 8% L (+) − with stirring. 3.2 parts of ascorbic acid aqueous solution was 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)
Butyl acrylate 7.5 parts Acrylic acid 1.5 parts Trichlorobromomethane 0.6 parts

[Emulsifier aqueous solution]
20% DBS aqueous solution 1.0 part Demineralized water 67.0 parts

[Initiator aqueous solution]
8% by mass aqueous hydrogen peroxide solution 18.9 parts 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 H2. 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 H>
Carbon black (Mitsubishi Chemical Co., Ltd.) manufactured by a furnace method with a 300 L internal volume equipped with a stirrer (propeller blade) and a toluene extract having an ultraviolet absorbance of 0.02 and a true density of 1.8 g / cm ³ Mitsubishi Carbon Black MA100S) 20 parts (40 kg), 20% DBS aqueous solution 1 part, nonionic surfactant (manufactured by Kao Corp., Emulgen 120) 4 parts, ion-exchanged water 75 parts with an electric conductivity of 2 μS / cm In addition, it was predispersed to obtain a pigment premix solution. The volume average diameter (Mv) of carbon black in the dispersion after pigment premixing measured with Nanotrac was 90 μm.

The pigment premix solution was supplied as a raw material slurry to a wet bead mill and subjected to one-pass dispersion. 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 100 μm (true density of 6.0 g / cm ³ ) were used as a dispersion 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. To obtain a black colorant dispersion H. The volume average diameter (Mv) of the colorant dispersion H measured with Nanotrac was 150 nm, and the solid content concentration was 24.2% by mass.

<Manufacture of toner mother particles H>
Using the following components, toner base particles H 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 H1 90 parts as solids (958.9 g as solids)
Polymer primary particle dispersion H2 10 parts colorant dispersion H as solid content 4.4 parts 20% DBS aqueous solution as colorant solid content In the core material agglomeration step, 0.15 part 20% DBS aqueous solution as solid content Circularization step Then, 6 parts as solid content

○ Core material agglomeration step Polymer primary particle dispersions H1 and 20 in a mixer (volume 12 L, inner diameter 208 mm, height 355 mm) equipped with a stirrer (double helical blade), heating / cooling device and raw material / auxiliary charging device % DBS aqueous solution was charged and mixed uniformly at an internal temperature of 10 ° C. for 10 minutes. Then at an internal temperature of 10 ° C., allowed to stir at 280 rpm, a 5 mass% aqueous solution of potassium _sulfate, 0.12 parts of a continuously added over 1 minute as K 2 SO _4, the colorant dispersion H 5 The mixture was continuously added over a minute and mixed uniformly at an internal temperature of 10 ° C.

  Thereafter, 100 parts of demineralized water was continuously added over 30 minutes, and then the internal temperature was raised to 48.0 ° C. over 67 minutes (0.5 ° C./min) while maintaining the rotational speed of 280 rpm. Next, after raising the temperature by 1 ° C. every 30 minutes (0.03 ° C./min), hold at 54.0 ° C., measure the volume median diameter (Dv50) using a multisizer, and grow to 5.15 μm. It was.

The stirring conditions at this time are as follows.
(A) Diameter of the stirring vessel (as a so-called general cylindrical shape): 208 mm
(B) Height of stirring container: 355 mm
(C) Peripheral speed at the tip of the stirring blade: 280 rpm, that is, 2.78 m / sec.
(D) Shape of stirring blade: Double helical blade (diameter 190mm, height 270mm, width 20mm)
(E) Position of the blade in the stirring vessel: 5 mm above the bottom of the vessel.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was continuously added over 6 minutes with the internal temperature of 54.0 ° C. and the rotation speed of 280 rpm, and held as it was for 60 minutes. At this time, the Dv50 of the particles was 5.34 μm.

○ Circularization Step Subsequently, the temperature was raised to 83 ° C. while adding a mixed aqueous solution of 20% DBS aqueous solution (6 parts as a solid content) and 0.04 part of water over 30 minutes, and then 1 ° C. every 30 minutes. The temperature was raised to 88 ° C., and heating and stirring were continued under these conditions until the average circularity reached 0.939 over 3.5 hours. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry. At this time, the Dv50 of the particles was 5.33 μm and the average circularity was 0.937.

Washing step The obtained slurry was extracted and suction filtered with an aspirator using 5 types C (Toyo Filter Paper No. 5C) filter paper. 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 step The solid material obtained here was spread on a stainless steel vat so as to have a height of 20 mm, and dried in a blow dryer set at 40 ° C. for 48 hours to obtain toner mother particles H.

<Manufacture of toner H>
○ External Addition Step To the obtained toner base particle H500 g, 8.75 g of Clariant H30TD silica as an external additive is mixed and mixed with a 9 L Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) at 3000 rpm for 30 minutes. 1.4 g of HAP-05NP calcium phosphate manufactured by Calcium Co., Ltd. was mixed, mixed at 3000 rpm for 10 minutes, and sieved with 200 mesh to obtain toner H.

Analyzing Step The “volume median diameter (Dv50)” measured using a multisizer of the toner H obtained here is 5.26 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 5.87%, the average circularity was 0.948, and the number variation coefficient was 18.0%.

Toner production example 8
<Production of toner mother particle I>
In the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing toner mother particle H”, “core material aggregation process”, “shell coating process”, and “circularization process” The toner base particles I were obtained in the same manner as in “Production of toner base particles H” in Example 7, except that “” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 5 minutes. Subsequently, the mixture was stirred at 280 rpm at an internal temperature of 10 ° C. and 0.12 part of a 5 mass% aqueous solution of potassium sulfate was continuously added over 1 minute, and then the colorant dispersion H was continuously added over 5 minutes. Mix evenly at a temperature of 10 ° C. Thereafter, 100 parts of demineralized water was continuously added over 26 minutes, and then the internal temperature was raised to 52.0 ° C. over 64 minutes (0.5 ° C./min) while maintaining the rotational speed of 280 rpm. Subsequently, after raising the temperature by 1 ° C. over 30 minutes (0.03 ° C./min), the temperature was maintained for 110 minutes, and the volume median diameter (Dv50) was measured using a multisizer to grow to 5.93 μm. The stirring conditions at this time were the same as in Example 7.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was continuously added over 6 minutes while maintaining the internal temperature at 53.0 ° C and the rotation speed at 280 rpm, and held as it was for 90 minutes. At this time, the Dv50 of the particles was 6.23 μm.

○ Circularization Step Subsequently, the mixture was heated to 85 ° C. while adding a mixed aqueous solution of 20% DBS aqueous solution (6 parts as a solid content) and 0.04 part of water over 30 minutes, and then 92 ° C. over 130 minutes. Until the average circularity reached 0.943, heating and stirring were continued under these conditions. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry. At this time, Dv50 of the particles was 6.17 μm, and the average circularity was 0.945. The washing, drying, and external addition steps were performed in the same manner as in Example 7.

External Addition Step After adding 7.5 g of Clariant H30TD silica as an external additive to 500 g of the resulting toner base particles I, and mixing with a 9 L Henschel mixer (Mitsui Mining Co., Ltd.) at 3000 rpm for 30 minutes, Maruo Calcium Toner I was obtained by mixing 1.2 g of HAP-05NP calcium phosphate manufactured by Co., Ltd., mixing at 3000 rpm for 10 minutes, and sieving with 200 mesh.

Analyzing Step The “volume median diameter (Dv50)” measured by using the toner I multisizer obtained here is 6.16 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 2.79%, the average circularity was 0.946, and the number variation coefficient was 19.2%.

Toner Production Example 9
<Manufacture of toner mother particle J>
In the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing toner mother particle H”, “core material aggregation process”, “shell coating process”, and “circularization process” The toner mother particles J were obtained in the same manner as in “Production of toner mother particles H” in Example 7, except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 10 minutes. Subsequently, the mixture was stirred at 280 rpm at an internal temperature of 10 ° C. and 0.12 part of a 5 mass% aqueous solution of potassium sulfate was continuously added over 1 minute, and then the colorant dispersion H was continuously added over 5 minutes. Mix evenly at a temperature of 10 ° C. Thereafter, 0.5 part of demineralized water was continuously added over 26 minutes, and then the internal temperature was raised to 52.0 ° C. over 64 minutes (0.5 ° C./minute) with the rotation speed being 280 rpm. Subsequently, after raising the temperature by 1 ° C. over 30 minutes (0.03 ° C./min), the temperature was maintained for 130 minutes, and the volume median diameter (Dv50) was measured using a multisizer to grow to 6.60 μm. The stirring conditions at this time were the same as in Example 7.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was continuously added over 6 minutes while maintaining the internal temperature at 53.0 ° C and the rotation speed at 280 rpm, and held as it was for 60 minutes. At this time, the Dv50 of the particles was 6.93 μm.

○ Circularization Step Subsequently, the mixture was heated to 90 ° C. while adding a mixed aqueous solution of 20% DBS aqueous solution (6 parts as a solid content) and 0.04 part of water over 30 minutes, and then 97 ° C. over 60 minutes. Until the average circularity reached 0.945, heating and stirring were continued under these conditions. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry. At this time, the Dv50 of the particles was 6.93 μm and the average circularity was 0.945. The washing / drying steps were performed in the same manner as in Example 7.

External Addition Step To the obtained toner base particles J500 g, 6.25 g of Clariant H30TD silica as an external additive is mixed and mixed with a 9 L Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) at 3000 rpm for 30 minutes. Toner J was obtained by mixing 1.0 g of HAP-05NP calcium phosphate manufactured by Calcium Co., Ltd., mixing at 3000 rpm for 10 minutes, and sieving with 200 mesh.

Analyzing Step The “volume median diameter (Dv50)” measured using the toner J multisizer obtained here is 6.97 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 1.85%, the average circularity was 0.946, and the number variation coefficient was 19.5%.

Toner comparative production example 2
<Manufacture of toner mother particles O>
In the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing toner mother particle H”, “core material aggregation process”, “shell coating process”, and “circularization process” The toner mother particles O were obtained in the same manner as in “Production of toner mother particles H” in Example 7, except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 10 minutes. Subsequently, the mixture was stirred at 280 rpm at an internal temperature of 10 ° C. and 0.12 part of a 5 mass% aqueous solution of potassium sulfate was continuously added over 1 minute, and then the colorant dispersion H was continuously added over 5 minutes. Mix evenly at a temperature of 10 ° C. Thereafter, 100 parts of demineralized water was continuously added over 30 minutes, and the internal temperature was raised to 34.0 ° C. over 40 minutes (0.6 ° C./min) with the rotation speed being 280 rpm. Subsequently, it hold | maintained for 20 minutes, the volume median diameter (Dv50) was measured using the multisizer, and it was made to grow to 3.81 micrometers.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was added over 6 minutes while maintaining the internal temperature of 34.0 ° C and the rotation speed of 280 rpm, and the state was maintained for 90 minutes.

○ Circularization process Subsequently, 20% DBS aqueous solution (6 parts as solid content) was added over 10 minutes while maintaining the rotation speed at 280 rpm (the same stirring speed as the aggregation process rotation speed), and then 76 ° C over 30 minutes. The mixture was heated and stirred until the average circularity reached 0.962. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry.

<Manufacture of toner K>
Thereafter, 100 parts of the toner base particles H of Example 7 and 1 part of the toner base particles O are mixed, and 8.75 g of Clariant H30TD silica as an external additive is mixed with 500 g of the toner base particle mixture K. , 9L Henschel mixer (Mitsui Mining Co., Ltd.) mixed at 3000rpm for 30 minutes, then mixed with Maruo Calcium Co., Ltd. HAP-05NP calcium phosphate 1.4g, mixed at 3000rpm for 10 minutes, sieved with 200 mesh and toner K was obtained.

Analyzing Step The “volume median diameter (Dv50)” measured using the toner K multisizer obtained here is 5.31 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 7.22%, the average circularity was 0.949, and the number variation coefficient was 19.2%.

Toner comparative production example 3
<Manufacture of toner mother particles L>
In the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing toner mother particle H”, “core material aggregation process”, “shell coating process”, and “circularization process” The toner base particles L were obtained in the same manner as in “Production of toner base particles H” in Example 7, except that “” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 10 minutes. Then at an internal temperature of 10 ° C., allowed to stir at 310 rpm, 5 minutes continuously added over 1 minute and 0.12 part of a 5 mass% aqueous solution of potassium sulfate as a _K 2 SO _4, the colorant dispersion H The mixture was continuously added over time and mixed uniformly at an internal temperature of 10 ° C.

  Thereafter, 100 parts of demineralized water was continuously added over 30 minutes, and the internal temperature was raised to 48.0 ° C. over 67 minutes (0.5 ° C./minute) while maintaining the rotation speed at 310 rpm. Next, after raising the temperature by 1 ° C. every 30 minutes (0.03 ° C./min), the temperature was maintained at 53.0 ° C., and the volume median diameter (Dv50) was measured using a multisizer and grown to 5.08 μm. .

The stirring conditions at this time were the same as in Example 7 except for the following (c).
(C) The peripheral speed at the tip of the stirring blade: 310 rpm, that is, 3.08 m / sec.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was continuously added over 6 minutes while maintaining the internal temperature of 54.0 ° C and the rotation speed of 310 rpm, and held as it was for 60 minutes. At this time, the Dv50 of the particles was 5.19 μm.

○ Circularization Step Subsequently, the temperature was raised to 83 ° C. while adding a mixed aqueous solution of 20% DBS aqueous solution (6 parts as a solid content) and 0.04 part of water over 30 minutes, and then 1 ° C. every 30 minutes. The temperature was raised to 90 ° C., and heating and stirring were continued under these conditions until the average circularity reached 0.939 over 2.5 hours. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry. At this time, the Dv50 of the particles was 5.18 μm and the average circularity was 0.940. The washing / drying steps were performed in the same manner as in Example 7.

External Addition Step To the obtained toner base particles L500 g, 8.75 g of Clariant H30TD silica as an external additive is mixed and mixed with a 9 L Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) at 3000 rpm for 30 minutes. Toner L was obtained by mixing 1.4 g of HAP-05NP calcium phosphate manufactured by Calcium Co., Ltd., mixing at 3000 rpm for 10 minutes, and sieving with 200 mesh.

Analyzing Step The “volume median diameter (Dv50)” measured using the multi-sizer of toner L obtained here is 5.18 μm, and “the number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 9.94%, the average circularity was 0.940, and the number variation coefficient was 20.4%.

Toner Comparative Production Example 4
<Manufacture of toner mother particles M>
In the agglomeration process (core material agglomeration process / shell coating process), circularization process, washing process, and drying process of “manufacturing toner mother particle H”, “core material aggregation process”, “shell coating process”, and “circularization process” The toner mother particles M were obtained in the same manner as in “Production of toner mother particles H” in Example 7, except that “A” was changed as follows.

○ Core material agglomeration process Dispersion of primary polymer particles in a mixer (volume 12L, inner diameter 208mm, height 355mm) equipped with a stirrer (double helical blade), heating / cooling device, concentrator, and raw material / auxiliary charging device Liquid H1 and 20% DBS aqueous solution were charged and mixed uniformly at an internal temperature of 10 ° C. for 10 minutes. Then at an internal temperature of 10 ° C., allowed to stir for 5 wt% aqueous solution of potassium sulfate from continuously added over 1 minute 0.12 parts as _K 2 SO ₄ at 310 rpm, over a period of 5 minutes colorant dispersion H Were added continuously and mixed uniformly at an internal temperature of 10 ° C.

  Thereafter, 100 parts of demineralized water was continuously added over 30 minutes, and the internal temperature was raised to 52.0 ° C. over 56 minutes (0.8 ° C./minute) while maintaining the rotation speed at 310 rpm. Next, after raising the temperature by 1 ° C. every 30 minutes (0.03 ° C./min), hold at 54.0 ° C., measure the volume median diameter (Dv50) using a multisizer, and grow it to 5.96 μm. It was.

The stirring conditions at this time were the same as in Example 7 except for the following (c).
(C) The peripheral speed at the tip of the stirring blade: 310 rpm, that is, 3.08 m / sec.

○ Shell coating step Thereafter, the polymer primary particle dispersion H2 was continuously added over 6 minutes while maintaining the internal temperature of 54.0 ° C and the rotation speed of 310 rpm, and held as it was for 60 minutes. At this time, Dv50 of the particles was 5.94 μm.

○ Circularization Step Subsequently, the mixture was heated to 88 ° C. while adding a mixed aqueous solution of 20% DBS aqueous solution (6 parts as solids) and 0.04 part of water over 30 minutes, and thereafter 1 ° C. every 30 minutes. The temperature was raised to 90 ° C., and heating and stirring were continued under these conditions until the average circularity reached 0.940 over 2 hours. Then, it cooled to 20 degreeC over 10 minutes, and obtained the slurry. At this time, the Dv50 of the particles was 5.88 μm and the average circularity was 0.943. The washing / drying steps were performed in the same manner as in Example 7.

External Addition Step To the obtained toner base particles M500 g, 7.5 g of Clariant H30TD silica is mixed as an external additive, and mixed with a 9 L Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) for 30 minutes at 3000 rpm, then Maruo. Toner M was obtained by mixing 1.2 g of HAP-05NP calcium phosphate manufactured by Calcium Co., Ltd., mixing at 3000 rpm for 10 minutes, and sieving with 200 mesh.

Analyzing Step The “volume median diameter (Dv50)” measured using a multisizer of the toner M obtained here is 5.92 μm, and “number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 5.22%, the average circularity was 0.945, and the number variation coefficient was 21.2%.

Toner Comparative Production Example 5
3 parts of toner base particles O are mixed with 100 parts of toner base particles J of Example 9, 500 g of this toner base particle mixture is mixed with 6.25 g of H30TD silica manufactured by Clariant as an external additive, and a 9 L Henschel mixer ( After mixing at 3000 rpm for 30 minutes with Mitsui Mining Co., Ltd., 1.0 g of HAP-05NP calcium phosphate manufactured by Maruo Calcium Co., Ltd. was mixed, mixed at 3000 rpm for 10 minutes, and sieved with 200 mesh to obtain toner N.

Analyzing Step The “volume median diameter (Dv50)” measured using the toner N multisizer obtained here is 6.88 μm, and “the number% of toner having a particle size of 2.00 μm to 3.56 μm”. (Dns) "was 9.08%, the average circularity was 0.952, and the number variation coefficient was 25.6%.

Example 7 to Example 9, Comparative Example 2 to Comparative Example 5
For the toners H to N, the actual image evaluation was performed in the actual image evaluation 2 using the photoconductor 2 described later. The results are shown in Table 3 below.

  In all of Examples 7 to 9, the afterimage (ghost), blur (solid followability), and cleaning properties were all good. The aforementioned “selective development” was not observed. On the other hand, none of Comparative Examples 2 to 5 was excellent in all of afterimage (ghost), blurring (solid followability) and cleaning properties. The toners H, I, and J have excellent actual performance when used in combination with the photoconductor 2 described later. However, the toners K, L, M, and N can be used in combination with the photoconductor 2 described later. It turned out to be inferior.

  FIG. 3 is a scanning electron micrograph (SEM photograph) of the toner of toner comparative production example 2 (toner K), and FIG. 4 is a toner of toner production example 7 (toner H). Comparing the two, it was found that FIG. 3 (Toner Comparative Production Example 2) contains more fine powder of 3.56 μm or less than FIG. 4 (Toner Production Example 7).

  FIG. 5 is an SEM photograph showing the adhesion state of the toner on the cleaning blade after the actual image evaluation of the toner (toner K) in Comparative toner production example 2. When such a toner containing a large amount of fine powder is printed for a long time, as shown in FIG. 5, fine powder of 3.56 μm or less having a high adhesion force is positively deposited on the cleaning blade in the image forming apparatus, and the bulk density is increased. It was found that a high levee was formed to inhibit toner conveyance. A portion surrounded by an ellipse in FIG. 5 is a dike on which fine powder of 3.56 μm or less is deposited.

<Photoconductor>
<Measuring method of CuKα characteristic X-ray (wavelength: 1.541 mm) of charge generation layer>
“Diffraction peak by CuKα characteristic X-ray of oxytitanium phthalocyanine contained in photosensitive layer” whose diffraction peak (Bragg angle) is limited in the present invention is actually contained in the photosensitive layer of oxytitanium phthalocyanine. It means the diffraction peak in the state.

  The diffraction spectrum by the CuKα characteristic X-ray of the photosensitive layer may be measured by any method as long as it can obtain the X-ray diffraction spectrum of the photosensitive layer itself. The method of forming on a surface and measuring is mentioned. A method for measuring the diffraction spectrum of the photosensitive layer according to the present invention by the CuKα characteristic X-ray, that is, the diffraction spectrum of the oxytitanium phthalocyanine by the CuKα characteristic X-ray will be described below. In the following sample preparation methods (1) and (2), the diffraction spectrum by CuKα characteristic X-rays of oxytitanium phthalocyanine is usually the same, and neither of them includes a treatment that changes the crystal structure. This is also the same as the diffraction peak of oxytitanium phthalocyanine contained in the actual photosensitive layer.

1. Sample preparation method (1)
A coating solution for forming a photosensitive layer was applied to an antireflective cover glass so as to have a film thickness of 10 μm or more and dried.
1. Sample preparation method (2)
As shown in the following photoconductor production examples 1 and 4 and comparative photoconductor production examples 1 and 2, the photoconductor from which the charge transport layer was peeled was immersed in methanol to peel the charge generation layer, and on the non-reflective cover glass Then, the separated charge generation layers were arranged and dried until a measurable film thickness was obtained.

2. Measuring apparatus and measuring conditions The measuring apparatus used was a diffractometer (Rigaku RINT2000) for a thin film sample using CuKα rays that were monochromatically paralleled by an artificial multilayer mirror. Measurement conditions are: X-ray output 50 kV, 250 mA, fixed incident angle (θ) 1.0 °, scanning range (2θ) 3-40 °, scanning step width 0.05 °, incident solar slit 5.0 °, incident slit The diffraction pattern was measured at 0.1 mm and a light receiving solar slit of 0.1 °.

<Measurement method of viscosity average molecular weight (Mv)>
The viscosity average molecular weight (Mv) of the binder resin (polycarbonate resin, polyarylate resin) used in the charge transport layer described in the following photoconductor production examples and comparative photoconductor production examples should be measured by the following measurement method. Determined by

Using a Ubbelohde capillary viscometer (dichloromethane flow time t ₀ : 136.16 seconds), the flow time (t) of the binder resin dichloromethane solution (concentration: 6.00 g / L) was measured at 20.0 ° C. Based on the following formula, the viscosity average molecular weight (Mv) of the binder resin was calculated.
ηsp = (t / t ₀ ) −1
a = 0.438 × ηsp + 1
b = 100 × (ηsp / C)
C = 6.00 [g / L]
η = b / a
Mv = 3207 × η1.205

<Example of photoconductor production>
Charge generation material production example 1
(Manufacture of CG1)
A concentrated sulfuric acid solution of oxytitanium phthalocyanine was prepared by slowly charging and dissolving 60 g of α-type oxytitanium phthalocyanine in 1.5 kg of concentrated sulfuric acid at 5 ° C. or lower. The obtained concentrated sulfuric acid solution of oxytitanium phthalocyanine was released into 15 kg of ice water at 5 ° C. or lower to precipitate oxytitanium phthalocyanine, and the precipitated oxytitanium phthalocyanine was separated by filtration. After filtration, the oxytitanium phthalocyanine was sufficiently washed with water until the pH of the cleaning solution became neutral to obtain an aqueous paste of oxytitanium phthalocyanine. In addition, solid content of this water paste was 12 mass%. 1 kg of n-octane was added to this water paste, milled with a glass bead of φ1 mm for 10 hours, and crystal type conversion was performed to obtain an oxytitanium phthalocyanine crystal used as a charge generating substance.

Photoconductor production example 1
A rutile type titanium oxide having an average primary particle size of 40 nm (“TTO55N” manufactured by Ishihara Sangyo Co., Ltd.) and 3% by mass of methyldimethoxysilane (“TSL8117” manufactured by Toshiba Silicone Co., Ltd.) with respect to the titanium oxide were added to a Henschel mixer. 1 kg of a raw slurry obtained by mixing 50 parts of surface-treated titanium oxide obtained by mixing with 120 parts of methanol, and using a zirconia bead having a diameter of about 100 μm (YTZ manufactured by Nikkato Co., Ltd.) as a dispersion medium, a mill volume of about 0 Using a 15-liter Ultra Apex Mill (UAM-015 type) manufactured by Kotobuki Kogyo Co., Ltd., dispersion treatment was performed for 1 hour in a liquid circulation state with a rotor peripheral speed of 10 m / second and a liquid flow rate of 10 kg / hour to produce a titanium oxide dispersion T1. did.

  The titanium oxide dispersion, a mixed solvent of methanol / 1-propanol / toluene, and ε-caprolactam [compound represented by the following formula (A)] / bis (4-amino-3-methylcyclohexyl) methane [the following formula Compound represented by (B)] / Hexamethylenediamine [Compound represented by the following formula (C)] / Decamethylene dicarboxylic acid [Compound represented by the following formula (D)] / Octadecamethylene dicarboxylic acid [Formula (E After the polyamide pellets are dissolved by stirring and mixing the pellets of the copolymerized polyamide having a composition molar ratio of 60% / 15% / 5% / 15% / 5%] , Ultrasonic dispersion using an ultrasonic transmitter with an output of 1200 W was performed for 1 hour, and a PTFE membrane filter (adva The weight ratio of the surface-treated titanium oxide / copolymerized polyamide is 3/1, and the weight ratio of the mixed solvent of methanol / 1-propanol / toluene is 7/1/2. The undercoat layer forming dispersion A1 having a solid content concentration of 18.0% by mass was obtained.

  The undercoat layer forming dispersion A1 is dip-coated on an anodized aluminum cylinder (outer diameter 30 mm, thickness 1.0 mm, surface roughness Ra = 0.02 μm), dried by heating, and dried. The undercoat layer was provided so that the film thickness of the film became 1.5 μm.

  As a charge generation material, 20 parts by weight of oxytitanium phthalocyanine (CG1) obtained in Charge Generation Material Production Example 1 and 280 parts by weight of 1,2-dimethoxyethane together with 800 parts by weight of glass beads having a diameter of 1 mm, a radius of 10 cm, Mix in a 15 cm high stainless steel cylindrical vessel and use a stirring blade equipped with 3 disc shaped stainless steel stirring blades with a radius of 8.5 cm to rotate at 1000 rpm for dispersion treatment for 1 hour. A titanium phthalocyanine dispersion was prepared.

  Subsequently, this dispersion, 10 parts by weight of polyvinyl butyral (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name “Denka Butyral” # 6000C), 487 parts by weight of 1,2-dimethoxyethane, 85 parts by weight of 4- A coating solution for charge generation layer was prepared by mixing methoxy-4-methyl-2-pentanone.

  The obtained coating solution for charge generation layer was measured according to <Measurement method of CuKα characteristic X-ray (wavelength 1.541 波長) of charge generation layer> (sample preparation method (1)) described above. As shown in Fig. 2, the Bragg angles (2θ ± 0.2 °) with respect to CuKα characteristic X-rays (wavelength 1.541Å) have main diffraction peaks at 9.0 ° and 27.2 °, and from 9.3 ° to 9 ° It was found to be a charge generation layer coating solution containing oxytitanium phthalocyanine having at least one main diffraction peak in the range of .8 °. Therefore, the oxytitanium phthalocyanine actually contained in the photoreceptor 1 should have a diffraction peak at the Bragg angle.

Next, the above-mentioned “aluminum cylinder provided with an undercoat layer” is dip coated on the charge generation layer coating solution, and the film thickness after drying becomes about 0.3 μm (0.3 g / m ² ). Thus, a charge generation layer was formed.

  Next, 50 parts by weight of a charge transport material represented by the following structural formula (6), 100 parts by weight of a polycarbonate resin represented by the structural formula (7), and 3,5-di-tert-butyl-4-hydroxy as an antioxidant 8 parts by weight of toluene and 0.05 parts by weight of silicone oil as a leveling agent are mixed with 640 parts by weight of a mixed solvent of tetrahydrofuran and toluene (80% by mass of tetrahydrofuran, 20% by mass of toluene) to prepare a coating solution for forming a charge transport layer. did.

Mv = 39000 d: e = 51: 49

  The cylinder on which the charge generation layer was previously formed was dip-coated in this charge transport layer forming coating solution to form a 18 μm thick charge transport layer after drying. The photoreceptor drum thus obtained is referred to as “photoreceptor 1”.

  The obtained photoreceptor 1 was cut into a size of 3 cm × 3 cm, and the cut photoreceptor 1 was immersed in 4-methoxy-4-methyl-2-pentanone for 5 minutes. Thereafter, the photoreceptor 1 was pulled up from 4-methoxy-4-methyl-2-pentanone, and the charge transport layer was peeled off. Subsequently, the photoreceptor 1 from which the charge transport layer was peeled was immersed in methanol, and then pulled up from the methanol to peel the charge generation layer. This operation was repeated 6 times, and the charge generation layers peeled off on the non-reflective cover glass were evenly arranged and dried completely to separate only the charge generation layer from the photoreceptor 1.

  The separated charge generation layer was measured in accordance with the above <Method for measuring CuKα characteristic X-ray (wavelength 1.541Å) of charge generation layer>. As in the case of preparing the charge generation layer coating solution, CuKα characteristic X Bragg angles (2θ ± 0.2 °) with respect to the line (wavelength 1.541Å) with main diffraction peaks at 9.0 ° and 27.2 ° and at least 1 in the range of 9.3 ° to 9.8 ° It was found to be a charge generation layer containing oxytitanium phthalocyanine having one main diffraction peak. This revealed that there was no difference between the crystal form of oxytitanium phthalocyanine contained in the charge generation layer coating solution and the crystal form of oxytitanium phthalocyanine contained in the charge generation layer in the photoreceptor 1.

Photoconductor production example 2
50 parts of titanium oxide powder coated with tin oxide containing 10% by mass of antimony oxide, 25 parts of resol type phenol resin, 20 parts of methyl cellosolve, 5 parts of methanol and silicone oil (polydimethylsiloxane / polyoxyalkylene copolymer) , Average molecular weight 3,000) was dispersed for 2 hours with a sand mill using φ1 mm glass beads to prepare a coating solution for a conductive layer. A conductive layer coating solution was applied on an aluminum cylinder (φ30 mm) by a dipping method and dried at 150 ° C. for 30 minutes to form a conductive layer having a thickness of 12.5 μm.

  On the conductive layer, a solution obtained by dissolving 40.0 parts of the same polyamide used in Photoconductor Production Example 1 in a mixed solvent consisting of 412 parts of methyl alcohol and 206 parts of n-butyl alcohol was applied by a dipping method. The film was dried at a temperature of 10 ° C. for 10 minutes to form an intermediate layer having a film thickness of 0.65 μm.

For the charge generation layer, the same coating solution for charge generation layer as that used in Photoconductor Production Example 1 was used. The charge generation layer was dip-coated on the aluminum cylinder on which the intermediate layer was formed. The charge generation layer was formed to be 3 μm (0.3 g / m ² ).

  For the charge transport layer, the charge transport material used in the preparation of the coating solution for the charge transport layer in the photoreceptor production example 1 is represented by 80 parts of the charge transport material represented by the following structural formula (8) and the structural formula (9). The charge transport material is changed to 10 parts, and the binder resin used in the preparation of the coating solution for the charge transport layer in the photoreceptor production example 1 is changed to a polyarylate resin represented by the following structural formula (10). Then, the same operation as in Photoconductor Production Example 1 was performed to obtain a coating solution for forming a charge transport layer.

  The cylinder on which the charge generation layer was previously formed was dip-coated in this charge transport layer forming coating solution to form a 18 μm thick charge transport layer after drying. The photoreceptor drum thus obtained is referred to as “photoreceptor 2”.

Mv = 55000, terephthalic acid: isophthalic acid = 1: 1

Photoconductor Production Example 3
The charge transport material used in the preparation of the coating solution for the charge transport layer in the photoreceptor 2 is 60 parts of the charge transport material represented by the structural formula (8), and 30 charge transport materials represented by the structural formula (8). In the same manner as in Photoconductor Production Example 2, except that the charge transport layer coating solution was prepared by changing the part and binder resin to polycarbonate resin represented by the following structural formula (11), “Photoconductor 3” was prepared. "

Mv = 60000

Photoconductor Production Example 4
5 parts by weight of oxytitanium phthalocyanine obtained in Charge Generation Material Production Example 1, 200 parts by weight of φ1 mm glass beads, 192 parts by weight of 1,2-dimethoxyethane, 21 parts by weight of 4-methoxy-4-methyl-2-pentanone, And 2.5 parts by weight of polyvinyl butyral (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name “Denka Butyral” # 6000C) was filled together into a 500-mL polyethylene wide-mouth bottle (manufactured by ASONE Co., Ltd.). The polyethylene wide-mouth bottle was dispersed for 1 hour using a paint shaker (manufactured by Toyo Seiki Seisakusho) to prepare a charge generation layer coating solution.

  The obtained charge generation layer coating solution was measured according to the above-described <Method for measuring CuKα characteristic X-ray (wavelength 1.541Å) of charge generation layer> (sample preparation method (1)). As shown in Fig. 2, the Bragg angles (2θ ± 0.2 °) with respect to CuKα characteristic X-rays (wavelength 1.541Å) have main diffraction peaks at 9.0 ° and 27.2 °, and from 9.3 ° to 9 ° It was found to be a charge generation layer coating solution containing oxytitanium phthalocyanine having at least one main diffraction peak in the range of .8 °. Accordingly, the oxytitanium phthalocyanine actually contained in the photoreceptor 4 should have a diffraction peak at the Bragg angle.

  By using the same aluminum cylinder and charge transport layer coating solution as in Photoconductor Production Example 2 except that the obtained charge generation layer coating solution was used, the same operations as in Photoconductor Production Example 2 were performed. Photoconductor 4 ”was prepared.

  The obtained photoreceptor 5 was cut into a size of 3 cm × 3 cm, and the cut photoreceptor 4 was immersed in 4-methoxy-4-methyl-2-pentanone for 5 minutes. Thereafter, the photoreceptor 5 was pulled up from 4-methoxy-4-methyl-2-pentanone, and the charge transport layer was peeled off. Subsequently, the photoreceptor 1 from which the charge transport layer was peeled was immersed in methanol, and then pulled up from the methanol to peel the charge generation layer. This operation was repeated 6 times, and the charge generation layers peeled off on the non-reflective cover glass were evenly arranged and dried completely to separate only the charge generation layer from the photoreceptor 4.

  When the separated charge generation layer was measured according to the above <Method for measuring CuKα characteristic X-ray (wavelength 1.541Å) of charge generation layer>, CuKα characteristic X-ray was prepared in the same manner as after the charge generation layer coating solution was prepared. Bragg angles (2θ ± 0.2 °) with respect to (wavelength 1.541Å) having main diffraction peaks at 9.0 ° and 27.2 °, and at least one in the range of 9.3 ° to 9.8 ° It is found that this is a charge generation layer containing oxytitanium phthalocyanine having a main diffraction peak, and is contained in the charge generation layer in the photoreceptor 4 and the crystal form of oxytitanium phthalocyanine contained in the charge generation layer coating solution. It became clear that there was no difference in the crystal form of oxytitanium phthalocyanine.

Comparative Photoconductor Production Example 1
The oxytitanium phthalocyanine used in the preparation of the coating solution for the charge generation layer in the photoreceptor 1 has Bragg angles of 9.6 °, 24.1 °, and 27.2 with respect to the CuKα characteristic X-ray (wavelength 1.541Å) shown in FIG. A comparative photoconductor 1 was obtained by performing the same operation as in Photoconductor Production Example 1 except that the coating solution for the charge generation layer was prepared by changing to oxytitanium phthalocyanine having a main diffraction peak at 0 °.

  The obtained coating solution for charge generation layer was measured according to <Measurement method of CuKα characteristic X-ray (wavelength 1.541 波長) of charge generation layer> (sample preparation method (1)) described above. The same diffraction pattern as that shown in FIG. That is, a charge containing oxytitanium phthalocyanine having main diffraction peaks at Bragg angles (2θ ± 0.2 °) of 9.6 ° and 27.2 ° with respect to CuKα characteristic X-rays (wavelength 1.541Å) similar to that before dispersion It was found to be a coating solution for the generation layer. Accordingly, the oxytitanium phthalocyanine actually contained in the comparative photoreceptor 1 should have a diffraction peak at the Bragg angle.

  The obtained comparative photoreceptor 1 was cut into a size of 3 cm × 3 cm, and the cut comparative photoreceptor 1 was immersed in 4-methoxy-4-methyl-2-pentanone for 5 minutes. Thereafter, the comparative photoreceptor 1 was pulled out from 4-methoxy-4-methyl-2-pentanone, and the charge transport layer was peeled off. Subsequently, the photoreceptor 1 from which the charge transport layer was peeled was immersed in methanol, and then pulled up from the methanol to peel the charge generation layer. This operation was repeated 6 times, and the charge generation layers peeled off on the non-reflective cover glass were evenly arranged and completely dried to separate only the charge generation layer from the comparative photoreceptor 1.

  When the separated charge generation layer was measured according to the above <Method for measuring CuKα characteristic X-ray (wavelength 1.541Å) of charge generation layer>, CuKα characteristic X-ray was prepared in the same manner as after the charge generation layer coating solution was prepared. It is found that the charge generation layer contains oxytitanium phthalocyanine having a main diffraction peak at a Bragg angle (2θ ± 0.2 °) of 9.6 ° and 27.2 ° with respect to (wavelength 1.541Å). It was revealed that there was no difference between the crystal form of oxytitanium phthalocyanine contained in the coating solution for coating and the crystal form of oxytitanium phthalocyanine contained in the charge generation layer in the comparative photoreceptor 1.

Comparative photoconductor production example 2
The oxytitanium phthalocyanine used in the preparation of the coating solution for the charge generation layer in the photoreceptor production example 2 has a Bragg angle of 9.5 °, 9.7 °, 24 with respect to the CuKα characteristic X-ray (wavelength 1.541Å) shown in FIG. Comparative Photoconductor 2 was prepared by performing the same operations as in Photoconductor Production Example 2 except that the coating solution for charge generation layer was prepared by changing to oxytitanium phthalocyanine having main diffraction peaks at .1 ° and 27.2 °. Got.

  The obtained coating solution for charge generation layer was measured according to <Measurement method of CuKα characteristic X-ray (wavelength 1.541１．５) of charge generation layer> (sample preparation method (1)) described above. As shown in Fig. 3, the main diffraction peaks at Bragg angles (2θ ± 0.2 °) of 9.5 °, 9.7 °, and 27.2 ° with respect to the same CuKα characteristic X-ray (wavelength 1.541 mm) as before dispersion are shown. It was found to be a coating solution for charge generation layer containing oxytitanium phthalocyanine. Therefore, the oxytitanium phthalocyanine actually contained in the comparative photoreceptor 2 should have a diffraction peak at the Bragg angle.

  The obtained comparative photoreceptor 2 was cut into a size of 3 cm × 3 cm, and the cut comparative photoreceptor 2 was immersed in 4-methoxy-4-methyl-2-pentanone for 5 minutes. Thereafter, the comparative photoreceptor 2 was pulled up from 4-methoxy-4-methyl-2-pentanone, and the charge transport layer was peeled off. Subsequently, the comparative photoreceptor 2 from which the charge transport layer was peeled was immersed in methanol, and then pulled up from the methanol to peel the charge generation layer. This operation was repeated 6 times, and the charge generation layers peeled off on the non-reflective cover glass were evenly arranged and completely dried to separate only the charge generation layer from the comparative photoreceptor 2.

  The separated charge generation layer was measured in accordance with the above <Method for measuring CuKα characteristic X-ray (wavelength 1.541Å) of charge generation layer>. As in the case of preparing the charge generation layer coating solution, CuKα characteristic X Charge generation layer containing oxytitanium phthalocyanine having main diffraction peaks at Bragg angles (2θ ± 0.2 °) of 9.5 °, 9.7 °, and 27.2 ° with respect to the line (wavelength 1.541 mm) It was found that there is no difference between the crystal form of oxytitanium phthalocyanine contained in the charge generation layer coating solution and the crystal form of oxytitanium phthalocyanine contained in the charge generation layer in the comparative photoreceptor 2. .

Comparative Photoconductor Production Example 3
Photoconductor production except that the coating solution used in Comparative Photoconductor Production Example 1 is used as the charge generation layer coating solution and the coating solution used in Photoconductor Production Example 3 is used as the charge transport layer coating solution. By performing the same operation as in Example 2, “Comparative Photoconductor 3” was obtained.

Examples 10 to 24, Comparative Examples 6 to 14
[Live-action evaluation 3]
A black drum cartridge for a commercially available tandem LED color printer MICROLINE Pro 9800PS-E (manufactured by Oki Data Co., Ltd.) and a black toner cartridge which are compatible with A3 printing, and the photosensitive members 1 to 4 and the comparative photosensitive member 1 are used. Except that the total length of the aluminum cylinder used in -3 was changed to a total length suitable for the printer, a photoconductor and a toner manufactured in the same manner were mounted, and the cartridge was mounted on the printer. The photoconductors used are the same as those of the photoconductors 1 to 4 and the comparative photoconductors 1 to 3 except for the entire length, and thus the photoconductors 1 to 4 and the comparative photoconductors 1 to 3 are respectively the same as the photoconductors. And

Specifications of MICROLINE Pro 9800PS-E:
Quadruple tandem color 36ppm, monochrome 40ppm
600 dpi to 1200 dpi
Contact roller charging (DC voltage applied)
With static elimination light

  Using this image forming apparatus, after printing out 1000 pieces of gradation images (Japan Imaging Society test chart), printing out a white background image and gradation image (Japan Imaging Society test chart), the fog value of the white background image, and The dot missing in the gradation image was evaluated. The results are shown in Table 5 below.

  The “fogging value” is adjusted by adjusting the whiteness meter so that the whiteness of the standard sample is 94.4, and the whiteness of the paper before printing is measured using this whiteness meter. Printing was performed by inputting a signal indicating white on the entire surface to the above-described laser printer, and then the whiteness of the paper was measured again, and the difference in whiteness before and after printing was measured. A large value means that the printed paper has many fine black spots and is dark, that is, the image quality is poor.

  For a gradation image, evaluation is made based on up to which density standard is printed without missing dots, and the lowest density standard printed without missing dots is defined as “corresponding density”. The smaller the corresponding density is, the better the drawing can be at a thinner part.

  In addition, the evaluation of the fine line reproducibility was carried out following the evaluation of fogging and scattering at the end of printing 1000 sheets. First, exposure was performed so that the line width of the latent image was 0.20 mm, and the fixed image was used as a measurement sample. At this time, since the measurement position of the line width is uneven in the width direction of the toner fine line image, the average line width of the unevenness was used as the measurement point. The fine line reproducibility was evaluated by calculating the ratio (line width ratio) of the measured line width to the latent image line width (0.20 mm).

The evaluation criteria for fine line reproducibility are shown below.
The ratio of the line width measurement value to the latent image line width (line width ratio) is
A: Less than 1.1.
B: 1.1 or more and less than 1.2.
C: 1.2 or more and less than 1.3.
D: 1.3 or more.

Example 25, Comparative Example 15
[Live-action evaluation 4]
For the toners A and G manufactured in the toner manufacturing example or the toner comparative manufacturing example, and the photoreceptor 1, for a commercially available tandem LED color printer MICROLINE Pro 9800PS-E (manufactured by Oki Data Corporation) that supports A3 printing. The black drum cartridge and the black toner cartridge were mounted on the printer, and the cartridge was mounted on the printer. Then, after removing the cleaning blade of this apparatus, the image was evaluated in the same manner as the actual image evaluation 3. When the toner A was used, there was no significant change from the actual image evaluation 3, but the toner G was used. In this case, large image deterioration was observed.

[Live-action evaluation 5]
Toner A is a non-magnetic one component (using photoconductor 1), a rubber developing roller contact development system, a process speed (development speed) of 164 mm / s, a belt transfer system, 600 dpi with a guaranteed life of 30000 sheets at a 5% printing rate. The sample was loaded in a machine cartridge, 50 charts with a 1% printing rate were continuously printed, and the stain on the image was visually observed. As a result, no clear stain was observed with the naked eye.

  As is clear from the above results, all of the toners A to F satisfying all the requirements of the present invention had a sufficiently small standard deviation in charge amount and a sharp charge amount distribution. Further, even in actual photograph evaluation using an electrophotographic photosensitive member having an intermediate layer, no stain was observed, or there was a slight stain, but it was at a usable level. The aforementioned “selective development” was also suppressed.

  On the other hand, in the image forming apparatus using the toner G that does not satisfy the requirements of the present invention, the standard deviation of the charge amount is large, the charge amount distribution is not sharp, and the above-described “selective development” was observed. Also in the actual image evaluation, a synergistic effect was confirmed by using the electrophotographic photosensitive member used in the image forming apparatus of the present invention.

[Live-action evaluation 6]
The exposure part of MICROLINE Pro 9800PS-E (Oki Data Co., Ltd.), which is compatible with A3 printing, was modified so that Nisshin Denshi, a small spot irradiation type blue LED (B3MP-8: 470 nm) can irradiate the photoreceptor. When the toner C and the photosensitive drum 1 or the photosensitive drum 2 were attached to the remodeling device and drawn, a good image was obtained. Further, when a strobe illumination power source LPS-203KS was connected to the small spot-illuminated blue LED and a point was written, a point image having a diameter of 8 mm could be obtained.

[Live-action evaluation 7]
When the photoreceptor 2 was introduced into a modified Hewlett-Packard HP-4600 machine, the toner B produced above was introduced as a developer and printed, a good image was obtained.

[Live-action evaluation 8]
The toner obtained by the suspension polymerization method having an average circularity of 0.990 is a non-magnetic one component (using the photoreceptor 1), a rubber developing roller contact developing method, a developing speed of 164 mm / s, and a belt transfer method. When it is loaded into a cartridge of a 600 dpi machine with a guaranteed life of 30,000 sheets at 5% printing rate, 50 charts with 1% printing rate are continuously printed and the stains on the image are visually observed. Many image defects were seen.

  In the live-action evaluation 1 to real-shoot evaluation 8 under various shooting conditions using various machines, any combination of the toner having a specific particle size distribution and the photosensitive member having a specific photosensitive layer in the present invention has a synergistic effect. And showed good live-action characteristics. On the other hand, a combination in which either the toner or the photoconductor does not satisfy the requirements of the present invention did not exhibit good real image characteristics.

  Since the image forming apparatus of the present invention is excellent in image stability during long-term use, it can be used for general printers, copiers, etc., and has recently been developed with high resolution, long life, and high-speed printing. It is also widely used in image forming methods and the like.

FIG. 2 is a schematic view illustrating an example of a non-magnetic one-component toner developing device used in the image forming apparatus of the present invention. 1 is a schematic diagram of a main part configuration showing an example of an image forming apparatus of the present invention. 10 is an SEM photograph of 1000 times that of the toner (toner K) of Comparative toner production example 2. 10 is a 1000 times SEM photograph of the toner (toner H) of toner production example 7. 10 is a 1000 times SEM photograph showing the adhesion state of toner on the cleaning blade after evaluation of actual image of toner (toner K) in Comparative Toner Example 2. The coating solution for the charge generation layer containing oxytitanium phthalocyanine used in the photoreceptor production example 1 was measured according to “Measurement method of CuKα characteristic X-ray (wavelength 1.541Å) of the charge generation layer (sample preparation method (1))”. It is the measured X-ray diffraction pattern. The coating solution for the charge generation layer containing oxytitanium phthalocyanine used in the photoreceptor production example 4 was measured according to “Measurement method of CuKα characteristic X-ray (wavelength 1.541Å) of the charge generation layer (sample preparation method (1))”. It is the measured X-ray diffraction pattern. It is the X-ray-diffraction pattern which measured the oxytitanium phthalocyanine used in the comparative photoreceptor manufacture example 1 according to the measuring method of the powder X-ray diffraction of the usual method. It is the X-ray-diffraction pattern which measured the oxytitanium phthalocyanine used in the comparative photoreceptor manufacture example 2 according to the measuring method of the powder X-ray diffraction of the usual method. The coating solution for charge generation layer containing oxytitanium phthalocyanine used in Comparative Photoconductor Production Example 2 is referred to as “Measurement method of CuKα characteristic X-ray (wavelength 1.541Å) of charge generation layer (sample preparation method (1))”. X-ray diffraction pattern measured according to

Explanation of symbols

11 Electrostatic latent image carrier 12 Toner transport member 13 Elastic blade (toner layer thickness regulating member)
14 Sponge roller (toner replenishment auxiliary member)
15 Stirrer blade 16 Toner 17 Toner hopper 1 Photoconductor (electrophotographic photoconductor)
2 Charging device (charging roller; charging unit)
3 Exposure equipment (exposure section)
4 Development device (development unit)
5 Transfer device 6 Cleaning device (cleaning part)
7 Fixing Device 41 Developing Tank 42 Agitator 43 Supply Roller 44 Developing Roller 45 Regulating Member 71 Upper Fixing Member (Pressure Roller)
72 Lower fixing member (fixing roller)
73 Heating device T Toner P Recording paper (paper, medium)

Claims (14)

An image forming apparatus comprising an electrophotographic photosensitive member having a photosensitive layer on a conductive support, and an electrostatic charge image developing toner, wherein the photosensitive layer of the electrophotographic photosensitive member has at least a CuKα characteristic X-ray (wavelength 1). Bragg angles (2θ ± 0.2 °) with respect to .541)) with main diffraction peaks at 9.0 ° and 27.2 ° and at least one main diffraction peak in the range of 9.3 ° to 9.8 ° And an electrostatic image developing toner satisfying all of the following (1) to (3):
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.0 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 size of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50).   The photosensitive layer of the electrophotographic photosensitive member has a dipole moment Pcal obtained by structure optimization calculation using semiempirical molecular orbital calculation using AM1 parameter, such that 0.2 (D) <P <2.1 (D 2. The image forming apparatus according to claim 1, further comprising: In the electrostatic image developing toner, the relationship between the volume median diameter (Dv50) and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm satisfies the following formula (3-1). The image forming apparatus according to claim 1 or 2.
(3-1) Dns ≦ 0.110EXP (19.9 / Dv50) In the electrostatic image developing toner, the relationship between the volume median diameter (Dv50) and the number% (Dns) of toner having a particle diameter of 2.00 μm to 3.56 μm satisfies the following formula (3-2). The image forming apparatus according to any one of claims 1 to 3.
(3-2) 0.0517EXP (22.4 / Dv50) ≦ Dns   5. The image forming apparatus according to claim 1, wherein the electrostatic charge image developing toner has a volume median diameter (Dv50) of 5.0 μm or more. 6.   6. The electrostatic charge image developing toner according to claim 1, wherein the number% (Dns) of the toner having a particle diameter of 2.00 μm to 3.56 μm is 6% by number or less. The image forming apparatus described in the item.   The electrostatic charge developing toner contains a wax, and the wax is contained in an amount of 4 to 20 parts by weight with respect to 100 parts by weight of the electrostatic charge developing toner. Item 7. The image forming apparatus according to any one of Items 6 above.   8. The image forming apparatus according to claim 1, wherein a developing process speed for the latent image carrier is 100 mm / sec or more. The image forming apparatus according to claim 1, wherein the following formula (G) is satisfied.
(G) Guaranteed lifetime number of sheets (sheets) x printing rate ≧ 400 (sheets) of the developer filled with developer   The image forming apparatus according to claim 1, wherein the resolution to the latent image carrier is 600 dpi or more.   11. The image forming apparatus according to claim 1, wherein the electrostatic charge image developing toner has a standard deviation of a charge amount of 1.0 to 2.0. 11.   12. The image forming apparatus according to claim 1, wherein an exposure wavelength of an exposure unit that forms an electrostatic latent image is monochromatic light having a wavelength of 380 to 500 nm. An electrophotographic photosensitive member having a photosensitive layer on a conductive support, and a cartridge including an electrostatic charge image developing toner, wherein the photosensitive layer of the electrophotographic photosensitive member has at least a CuKα characteristic X-ray (wavelength of 1.541 mm). Bragg angles (2θ ± 0.2 °) with main diffraction peaks at 9.0 ° and 27.2 ° and at least one main diffraction peak in the range of 9.3 ° to 9.8 ° A cartridge containing oxytitanium phthalocyanine and wherein the electrostatic image developing toner satisfies all of the following (1) to (3).
(1) The volume median diameter (Dv50) is 4.0 μm or more and 7.0 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 size of 2.00 μm to 3.56 μm satisfies Dns ≦ 0.233EXP (17.3 / Dv50).   The photosensitive layer of the electrophotographic photosensitive member has a dipole moment Pcal obtained by structure optimization calculation using semiempirical molecular orbital calculation using AM1 parameter, such that 0.2 (D) <P <2.1 (D The cartridge according to claim 13, further comprising an organic charge transporting material satisfying