JP2011028049A - Method of manufacturing toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a toner for providing a stable charging characteristic even in a developing device requiring flowability of a developer and stress resistance by dispersing a colorant uniformly and finely in the toner. <P>SOLUTION: In this method of manufacturing the toner, a raw material mixture containing at least a binder resin and a colorant is molten and kneaded using an extruder, and the following conditions are established. (i) The softening point Tm(°C) of the binder resin is 80°C or higher and 140°C or lower. (ii) The extruder has a melting/kneading shaft of a same-direction two-axis extrusion type, the length (L) of a melting section of the melting/kneading shaft is 550 mm or longer and 1500 mm or shorter, and the ratio (L/D) to the diameter (D) of the melting/kneading shaft is 10.0 or higher and 20.0 or lower. (iii) The relation among the barrel setting temperature Ta(°C) of a kneading section of the melting/kneading shaft, the softening point Tm(°C) of the binder resin, and the outflow starting temperature Tfb(°C) of the binder resin is Tfb≤Ta≤Tm. (iv) The bulk density of the raw material mixture is 0.20 g/cm<SP>3</SP>or higher and 0.50 g/cm<SP>3</SP>or lower. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing toner used for development in an image forming method such as an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or a toner jet method.

  When the toner for electrophotography is produced by a pulverization method, it is obtained by mixing a binder resin, a colorant, a release agent and a charge control agent, if necessary, melt kneading, pulverization and classification. Furthermore, fluidity, developability, and transferability may be improved by externally adding a fluidity-imparting agent such as silica or spheroidizing after classification, if necessary.

  In a full-color copying machine, an electrostatic charge image is formed on an image carrier, and the formed electrostatic charge image is cyan toner, magenta toner, yellow toner, and black toner, and each color toner is applied using a subtractive color mixing action. Develop by overlaying. Then, each color toner image formed by development is finally superimposed and transferred onto plain paper or a transfer material, and the toner image superimposed on the transfer material is fixed on the transfer material, thereby obtaining a desired color image. Forming. In recent full-color copying machines, higher speed and higher reliability have been strictly demanded. As a result, the performance required for the toner is increasing.

There are various performances required for the toner, but particularly important characteristics for the toner are appropriate chargeability and good color mixing properties, and that they can be obtained stably over a long period of time. For this purpose, it is indispensable that the components such as the colorant, the release agent, and the charge control agent are uniformly and finely dispersed in the binder resin. is important.
This is because full color toner expresses a desired color by superposing toners. For this reason, when the colorant is poorly dispersed, the upper toner layer interferes with the color of the lower toner layer when the colors are mixed. In addition, the colorant has an influence on charging, and if the dispersion thereof is poor, the toner charge distribution becomes broad or the rise of charging becomes slow. In particular, in recent years, a developer using two sleeves has been used for the purpose of obtaining high-definition images, and an auto-refresh development system has been used for the purpose of extending the life of the developer. There is an increasing demand for crystallization.

In order to improve the dispersibility of the colorant and improve the transparency of the toner, it is necessary to reduce the average particle diameter of the colorant in the toner. For this purpose, a method has been proposed in which the bulk density of the raw material during kneading is reduced to improve the dispersion state of the material in the previous stage of the kneading process (for example, Patent Document 1). However, with this method, since the bulk density is too small, the supply amount when supplying from the raw material supply port to the kneader becomes unstable. Therefore, the material is clogged at the raw material input port of the kneader, and there is a problem in productivity.
Further, by increasing the share at the time of kneading by setting the temperature at the time of kneading to be low, kneading is performed by self-heating to improve the dispersibility of the colorant (for example, Patent Document 2). However, with this method, the temperature of the kneaded product due to self-heating becomes too high, causing re-aggregation of the colorant and causing a problem in transparency.

Furthermore, a method that defines the ratio (L / D) between the length and diameter of the kneading shaft has also been proposed (for example, Patent Document 3). In this method, there is no regulation for the bulk density, and therefore, when the L / D is small, the dispersion of the colorant may be insufficient. In addition, a method of suppressing heat generation during kneading by reducing the resin particle size of the raw material and using a water-containing paste has been proposed (for example, Patent Document 4). With this method, there is no description of L / D, and it is highly possible that the water-containing paste alone is insufficient for suppressing self-heating during kneading.

  In recent digital multi-function peripherals and full-color copiers using two-component development methods, so-called multi-stage development methods, in which development is performed using a plurality of developer bearing members, are widely used with higher image quality and higher speed. Proposed. This multi-stage development system is preferably used because there are many opportunities for rubbing between the magnetic brush and the surface of the photosensitive drum, and a wide development area can be secured, so that a high-definition and high-density image can be obtained. However, developer deterioration is likely to occur due to large stress applied to the developer between the developing sleeve and the developer layer thickness regulating member (between S and B) and between the developing sleeve and the developing sleeve (between SS). There is. Toners for this system are not yet fully studied.

Japanese Patent Laid-Open No. 8-21651 JP-A-8-129270 Japanese Patent No. 3101480 JP-A-2005-352131

  An object of the present invention is to provide a toner manufacturing method that solves the problems in the above-described conventional technology and enables the colorant to be uniformly and finely dispersed in the toner.

  As a result of intensive studies, the present inventors have made it possible to disperse the colorant particles uniformly and finely in the toner by setting the kneading conditions and the raw material mixture during toner production to specific physical properties. The inventors have found that a toner having reproducibility and excellent charging stability can be obtained, and the present invention has been achieved.

That is, the present invention is as follows.
In a production method for obtaining a toner by melt-kneading a raw material mixture containing at least a binder resin and a colorant using an extruder,
i) The binder resin has a softening point Tm (° C) of 80 ° C or higher and 140 ° C or lower,
ii) The extruder has a biaxial extrusion type in which the melt-kneading shaft is in the same direction, the length (L) of the melted portion of the melt-kneading shaft is not less than 550 mm and not more than 1500 mm, and the diameter (D) of the melt-kneading shaft is Ratio (L / D) is 10.0 or more and 20.0 or less,
iii) Barrel set temperature Ta (° C.) of the kneading part of the melt-kneading shaft and softening point Tm of the binder resin
(° C.) and the outflow start temperature Tfb (° C.) of the binder resin are Tfb ≦ Ta ≦ Tm,
iv) A method for producing a toner, wherein the raw material mixture has a bulk density of 0.20 g / cm ³ or more and 0.50 g / cm ³ or less.

  According to the present invention, since the colorant particles can be uniformly and finely dispersed in the toner, it is possible to provide a toner manufacturing method in which a toner having high transparency and color reproducibility can be obtained.

It is the schematic of the biaxial kneading apparatus used suitably for this invention. FIG. 2 is a detailed view of a kneading shaft portion in the kneading apparatus of FIG. It is a 1st example of the kneading | mixing axis | shaft of the kneading part in a kneading apparatus. It is a 2nd example of the kneading | mixing axis | shaft of the kneading part in a kneading apparatus. It is a 3rd example of the kneading | mixing axis | shaft of the kneading part in a kneading apparatus. It is the schematic of the surface modification apparatus used suitably for this invention. FIG. 7 is an example of a dispersion rotor in the surface modification apparatus of FIG. 6. It is sectional drawing of the developing device used suitably for this invention. It is a figure which shows the circulation state of the developer used suitably for this invention. FIG. 3 is a schematic diagram illustrating an example of a fixing device in which the fixing property of the toner of the present invention is evaluated. FIG. 6 is a schematic diagram illustrating an example of an image on which the fixing property of the toner of the present invention has been evaluated. FIG. 6 is a schematic diagram illustrating an example of an image on which the fixing property of the toner of the present invention has been evaluated.

The kneader used in the toner production method of the present invention is a same-direction biaxial extruder. The twin-screw extruder is a kneader in which two kneading shafts called paddles pass through a barrel that is a heating cylinder that keeps the temperature constant. An example is shown in FIG. The raw material mixture is supplied from one end of the kneading shaft, heated to be in a molten state, kneaded by rotation of the kneading shaft, and extruded from the other end. A vent hole mainly for degassing may be installed along the way.

  FIG. 2 shows a schematic diagram of the kneading shaft. The cross-section of the kneading shaft is a propeller-like or triangular one, and is set with a phase shift so that one tip always rotates as if rubbing the other. This structure has a self-cleaning action of feeding the kneaded material forward without adhering to the kneading shaft and barrel wall. In the present application, the rotation directions of the two kneading shafts need to be the same direction. By rotating the kneading shaft in the same direction, an appropriate shearing force can be applied, the colorant can be uniformly dispersed, and the crystal growth of the colorant can be suppressed. When the rotation of the kneading shaft is in a different direction, the shearing force is too strong and self-heating occurs during the kneading, so that the colorant grows in crystals and the charging stability and transparency are deteriorated. In addition, since the rotation of the kneading shaft is in a different direction, the raw material mixture is not bite and production tact is difficult to obtain.

In the present application, the length (L) of the melted portion of the melt-kneading shaft is 550 mm or more and 1500 mm or less, and the ratio (L / D) to the diameter (D) of the melt-kneading shaft is 10.0 or more and 20.0 or less. Is a feature. By these, the melt residence time of the mixture can be optimized and the dispersion of the raw materials can be controlled. The melting portion of the kneading shaft is a portion of the kneading shaft from the barrel next to the material supply port to the extrusion port. Usually, the barrel of the material supply port is not melted because it is necessary to let the material bite into the kneading shaft. Therefore, in this application, it is not set as a fusion | melting part. The length of the melting part of the kneading shaft is 550mm
If it is smaller or if L / D is smaller than 10.0, the mixture has too short a residence time, so that sufficient kneading cannot be performed and the dispersion of the colorant becomes non-uniform and high coloring power cannot be obtained. . If the length of the melted part of the kneading shaft is greater than 1500 mm or if L / D is greater than 20.0,
Since the melt residence time is too long, too much heat is applied to the kneaded product, so that the colorant grows in crystals and the charging stability and transparency are deteriorated. Further, the fluidity of the developer after endurance deteriorates, and streaks and unevenness occur. In particular, in the multistage development system, the stress applied to the developer between the developing sleeve and the developing sleeve is large. Therefore, if the dispersibility of the colorant is poor, charge-up is likely to occur. The length (L) of the melted part is more preferably 600 mm or more and 1400 mm or less, and further preferably 600 mm or more and 1300 mm or less. Further, L / D is more preferably 11.0 or more and 19.0 or less, and further preferably 11.0 or more and 16.5 or less.

The binder resin has a softening point Tm (° C.) of 80 ° C. or more and 140 ° C. or less, the barrel set temperature Ta (° C.) of the kneading part of the melt-kneading shaft, the softening point Tm (° C.) of the binder resin, and the binder resin. It is necessary that the relationship between the outflow start temperature Tfb (° C.) of the adhesion resin is Tfb ≦ Ta ≦ Tm. The softening point of the binder resin has a correlation with the color mixing property and blocking property of the toner. When the softening point is lower than 80 ° C., the blocking property is deteriorated. When the softening point is higher than 140 ° C., the color mixing property is deteriorated. More preferable Tm is 90 ° C. or higher and 130 ° C. or lower, and further preferably 90 ° C. or higher and 120 ° C. or lower. The softening point of the binder resin can be adjusted by the monomer composition of the resin, the reaction time during polymerization, the temperature, the gel amount, and the like. For example, the softening point is increased by adding a large amount of a crosslinking component (trimellitic acid or the like) as the monomer, or by promoting the polymerization by increasing the reaction time or temperature. It can also be adjusted by mixing a plurality of resins. In order to set the range of the softening point of the binder resin to the above range, for example, the ratio of the alcohol component contained in the polyester component is 50 to 70 mol%, the ratio of the acid component is 30 to 50 mol%, and the reaction time is set. It is mentioned to make it 5 hours or more. Further, the ratio of the crosslinking component such as trimellitic acid may be 10 mol% or less.
The binder resin outflow start temperature Tfb (° C.) in the present invention is a temperature at which the binder resin changes from a powder state to a molten state and starts to flow out.
Tfb can be adjusted by the monomer composition of the resin, the reaction time and temperature during polymerization, and the like. For example, the outflow start temperature is increased by adding a large amount of a crosslinking component (trimellitic acid or the like) as a monomer or by increasing the reaction time or temperature to promote polymerization. It can also be adjusted by mixing a plurality of resins.
Tfb is preferably 70 ° C. or higher and 110 ° C. or lower. More preferably 75 ° C or higher,
It is 105 ° C. or lower.
In order to make Tfb within the above range, for example, the ratio of the alcohol component contained in the polyester component is 50 to 70 mol%, the ratio of the acid component is 30 to 50 mol%, and the reaction time is 5 hours or more. Can be mentioned.

  In this application, using such a binder resin, it is one of the features that the barrel temperature of the kneading shaft kneading part is set to be not less than the outflow start temperature of the binder resin and not more than the softening point. The kneading shaft is roughly divided into two types, one being a feed screw portion and the other being a kneading portion. A schematic diagram of the screw portion is shown in FIG. The screw part is an S-shaped screw as shown in the figure, and has a function of feeding the kneaded product forward while heating. When the viscosity of the kneaded product in the cylinder is high, the screw part wall and the kneaded product Although it is kneaded by a shearing force due to friction, if it is low, it is hardly kneaded.

  On the other hand, as the kneading part, a combination of propeller-like blocks as shown in FIGS. 3 and 4, a pineapple-like thing as shown in FIG. 5, a return screw that feeds in the direction opposite to the extrusion is used. This portion has little effect of feeding the kneaded product forward, and the kneaded product stays and fills. The kneading is carried out in response to the volume change of compression and stretching as the kneading shaft rotates. When the kneading portion is short or absent, the kneaded material is hardly retained and is extruded before the kneaded material is completely melted.

  In order to disperse the material, it is important to control the set temperature of the kneading part. That is, the setting temperature of the kneading part is set to a temperature higher than the binder resin outflow start temperature. If the temperature is lower than the outflow start temperature, the raw material is pushed out before being melted because it is close to the state of powder when kneaded. Therefore, the dispersion of the colorant is insufficient, and particles of only the resin not containing the colorant are generated, and a high coloring power cannot be obtained.

  It is also necessary to set the barrel setting temperature of the kneading part to a temperature lower than the softening point of the binder resin. If the barrel setting temperature of the kneading part is set to a temperature higher than the softening point, the viscosity of the raw material becomes too small in the kneading part. As a result, the effect of compression and stretching accompanying rotation of the kneading shaft performed in the kneading section is small. Therefore, since the share concerning a raw material becomes weak, dispersion | distribution of a coloring agent becomes inadequate. In the present application, by setting the barrel set temperature to a temperature lower than the softening point, a high dispersion of the colorant can be obtained by effectively obtaining a share during kneading of the kneading part. As a result, long-term charging stability can be obtained even in a developing system that develops using a plurality of developer carriers, such as a multistage developing system, which is severely deteriorated.

Furthermore, the bulk density of the raw material mixture must be 0.20 g / cm ³ or more and 0.50 g / cm ³ or less. In the present application, the melt residence time at the time of kneading is shorter than in the conventional method. Therefore, in order to improve the dispersibility of the material, it is necessary to control the bulk density of the raw material mixture. If the bulk density of the raw material mixture is less than 0.20 g / cm ³ , the raw material does not bite into the kneading shaft, so that kneading cannot be performed. On the other hand, if the bulk density of the raw material mixture is larger than 0.50 g / cm ³ , the raw material has a large particle size and is insufficiently dispersed. Preferably, the bulk density of the raw material mixture is 0.25 g / cm ³ or more and 0.45 g / cm ³ or less.

In the present application, it is necessary to control the bulk density of the raw material mixture. Although the method to control is not limited, For example, the method of adjusting with the particle size of a raw material, the method of adding a fluidizing agent etc., the mixing conditions of a raw material, etc. are mentioned. Among these, it is preferable to adjust with the particle size of the raw material contained in a raw material mixture. The raw material for adjusting the particle size is, for example, the particle size of the binder resin or the toner obtained at the time of pulverization classification. In the case of the binder resin, the volume average particle diameter of the binder resin is preferably 10 μm or more and 300 μm or less. In the case of 300 μm or less, the dispersibility of the colorant is improved and the coloring power is improved. Moreover, when it is 10 μm or more, the biting property at the time of kneading is improved, and the production tact tends to be improved.
Further, in the case of toner, it may be a finely pulverized product obtained at the time of pulverization, fine powder obtained at the time of classification, or toner particles.

Next, a procedure for manufacturing toner will be described.
First, in the raw material mixing step, as a toner internal additive, at least a binder resin and a colorant are weighed and mixed in a predetermined amount and mixed. Examples of the mixing apparatus include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, and a Nauter mixer. Moreover, it is also possible to use another material as an internal additive as needed. For example, a mold release agent, a charge control agent, etc. are mentioned.

In the present application, water may be added to the raw material mixture. Although any method may be used for adding water, a method of adding water as it is before mixing the raw materials is preferable. By adding water, the biting property at the time of kneading is improved, so that a high production tact is easily obtained. In addition, the presence of water tends to moderately suppress self-heating during kneading, suppress the crystal growth of the colorant, and improve the charging stability and transparency.
Further, the toner raw material mixture mixed as described above is melt-kneaded to disperse the raw materials. The kneading machine is not particularly limited as long as it is a twin screw extruder in the same direction.
For example, PCM type twin screw extruder (Ikegai Co., Ltd.), TEM type twin screw extruder (manufactured by Toshiba Machine Co., Ltd.), TEX type twin screw extruder (manufactured by Nippon Steel Corporation), KTX type twin screw extruder A machine (manufactured by Kobe Steel) is generally used.

The kneading shaft may have any number of kneading portions, but is preferably one in order to obtain an effective material dispersion state. Also, the length of all kneading parts (Ln
In order to obtain an effective material dispersion state, it is preferable that Ln / L is not less than 0.10 and not more than 0.45. When Ln / L is smaller than 0.10, retention during kneading is insufficient, and the dispersibility of the material tends to deteriorate. When Ln / L is larger than 0.45, the shear during kneading is too strong, and the molecular chain is broken, so that the fixability tends to be adversely affected.

  In the present application, a cooling means may be provided inside the melt-kneading shaft. As a cooling means, for example, there is a method of flowing cooling water inside the melt-kneading shaft. By having the cooling means, the temperature of the shaft portion to which the raw material mixture is supplied can be suppressed. Therefore, since the raw material mixture at the time of supply can be conveyed inside the kneader in a state close to powder, good biting properties can be obtained.

Furthermore, the kneaded material obtained by melt-kneading the toner raw material mixture is melt-kneaded,
It is preferable to be cooled through a cooling step that is rolled with two rolls or the like and cooled with water or the like.
The cooled product of the colored resin composition obtained above is then pulverized to a desired particle size in the pulverization step. In the pulverization process, first, coarse pulverization is performed with a crusher, a hammer mill, a feather mill or the like, and further, an IDS type pulverizer (manufactured by Nippon Pneumatic Industry Co., Ltd.) or a crypt of a mechanical pulverizer. It is pulverized by Ron System (manufactured by Kawasaki Heavy Industries, Ltd.), Super Rotor (manufactured by Nissin Engineering Co., Ltd.), turbo mill (manufactured by Turbo Industry Co., Ltd.) and the like.

  After that, if necessary, classification is performed using a classifier such as an inertia classification type elbow jet (manufactured by Nippon Steel Mining Co., Ltd.) or a centrifugal classification type turboplex (manufactured by Hosokawa Micron Co., Ltd.). Through a classification step, a classified product (toner particles) having a weight average particle size of 3 to 11 μm is obtained. Furthermore, if necessary, a surface modification (spheronization treatment) step is performed, for example, using a hybridization system (manufactured by Nara Machinery Co., Ltd.) or a mechano-fusion system (manufactured by Hosokawa Micron Corporation). To obtain a classified product (toner particles).

  In the present invention, the surface modification apparatus shown in FIG. 6 that can perform classification and surface modification treatment at the same time is preferably used.

  The surface modification apparatus shown in FIG. 6 includes a casing 55, a jacket (not shown) through which cooling water or antifreeze liquid can be passed, a classification rotor 41 that is a classification means for separating fine particles having a predetermined particle size or less, and a machine for particles. A dispersion rotor 46, which is a surface treatment means for treating the surface of the particles with a specific impact, a liner 44 provided around the outer periphery of the dispersion rotor 46 at a predetermined interval, and a classification rotor 41. Among the divided particles, fine particles having a predetermined particle size or less among the particles divided by the guide ring 49 and the classification rotor 41 that guide the particles including the predetermined particle size to the dispersion rotor 46 of the apparatus. A fine powder collecting discharge port 42 which is a discharge means for discharging outside, a cold air introduction port 45 which is a particle circulation means for sending particles whose surface is processed by the dispersion rotor 46 to the classification rotor 41, Child has a raw material supply port 43 for introducing into the casing 55 within a closable powder outlet 47 and the discharge valve 48 for discharging the treated surface particles from the casing 55 inside.

  The classification rotor 41 is a cylindrical rotor and is provided at one upper end portion in the casing 55. The fine powder collection outlet 42 is provided at one end of the casing 55 so as to discharge particles inside the classification rotor 41. The raw material supply port 43 is provided at the center of the peripheral surface of the casing 55. The cold air inlet 45 is provided on the other end surface side of the peripheral surface of the casing 55. The powder discharge port 47 is provided at a position facing the raw material supply port 43 on the peripheral surface of the casing 55. The discharge valve 48 is a valve that freely opens and closes the powder discharge port 47.

  A dispersion rotor 46 and a liner 44 are provided between the cold air introduction port 45 and the raw material supply port 43 and the powder discharge port 47. The liner 44 is provided along the inner peripheral surface of the casing 55. As shown in FIG. 7, the distributed rotor 46 includes a disk and a plurality of square disks 50 arranged along the normal line of the disk at the periphery of the disk. The dispersion rotor 46 is provided on the lower upper surface of the casing 55, and is provided at a position where a predetermined interval is formed between the liner 4 and the square disk 50. A guide ring 49 is provided at the center of the casing 55. The guide ring 49 is a cylindrical body and is provided so as to extend from a position covering a part of the outer peripheral surface of the classification rotor 41 to the vicinity of the classification rotor 46. The guide ring 49 includes a first space 51 that is a space between the outer peripheral surface of the guide ring 49 and an inner peripheral surface of the casing 55 in the casing 55, and a second space that is a space inside the guide ring 49. A space 52 is formed.

The dispersion rotor 46 may have a cylindrical pin instead of the square disk 50. In the present embodiment, the liner 44 is provided with a large number of grooves on the surface facing the rectangular disk 50, but may have no grooves on the surface. Moreover, the installation direction of the classification rotor 41 may be vertical as shown in FIG. 6 or horizontal. Further, the number of classification rotors 41 may be single or multiple as shown in FIG.

  Further, a classified product (toner particles) may be obtained through a sieving step using a sieving machine such as a wind-type sieving high voltor (manufactured by Shin Tokyo Machine Co., Ltd.). Further, it may include a step of externally adding an external additive, and a predetermined amount of toner particles as a classified product and an external additive such as silica and titanium oxide are blended to form a powder such as a Henschel mixer or a super mixer. A toner can be obtained by stirring and mixing using a high-speed stirrer that gives a shearing force as an external additive.

Examples of the colorant used in the present invention include the following.
Examples of the magenta colorant include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 150, 163, 202, 206, 207, 209, C.I. I. Pigment violet 19, C.I. I. Examples thereof include magenta color pigments such as Vat Red 1, 2, 10, 13, 15, 23, 29, and 35.

  Although the above pigment may be used alone, it is more preferable from the viewpoint of the image quality of a full color image to improve the sharpness by using a dye and a pigment together. Examples of the magenta dye include C.I. I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 2, 881, 83, 84, 100, 109, 121, C.I. I. Disper thread 9, C.I. I. Solvent Violet 8, 13, 14, 21, 27, C.I. I. Oil-soluble dyes such as disperse violet 1, C.I. I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, C.I. I. Basic dyes such as basic violet 1,3,7,10,14,15,21,25,26,27,28 are listed.

Examples of cyan colorants include C.I. I. Pigment blue 2, 3, 15, 16, 17, C.I. I. Bat Blue 6, C.I. I. Acid Blue 45 or a coloring pigment for cyan such as a copper phthalocyanine pigment in which 1 to 5 phthalimidomethyl groups are substituted on the phthalocyanine skeleton.
Examples of the colorant for yellow include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 65, 73, 74, 83, 180, C.I. I. Examples thereof include yellow colored pigments such as vat yellow 1, 3, 20 and the like. Among these, a monoazo pigment is preferable from the viewpoint of transparency and coloring power.
Monoazo pigments have low migration resistance due to their low molecular weight, that is, low dispersion stability in resins. Therefore, it is easy to maintain the dispersed state by performing kneading by self-heating with an appropriate shearing force and a kneading temperature setting below the softening point of the resin as in the present application. This is because if the temperature at the time of dispersion, that is, the temperature setting at the time of kneading is increased, the solubility of the pigment increases and the dispersion becomes easier. However, when the solubility is lowered after cooling, the pigment molecules are close to a supersaturated state, and the dissolved pigment molecules are likely to recrystallize and cause particle growth. Therefore, it is preferable to apply the production method appropriately set to the shearing force and the kneading temperature to the monoazo pigment.
The content of these colorants is preferably 1 to 10 parts by mass, and more preferably 3 to 8 parts by mass with respect to 100 parts by mass of the binder resin in the toner.

As the black colorant, carbon black, iron oxide, and those which are toned in black using the yellow / magenta / cyan colorant shown above can be used.
In order to improve the dispersibility, the colorant may be added as a master batch in which the binder resin and the colorant are previously kneaded. In the master batch process, when the binder resin and the colorant are kneaded, the ratio of the binder resin and the colorant in terms of solid mass is 90:10 to 40:60, preferably 85:15 to 45. : 55 is good. When the ratio of the colorant to the binder resin is less than 10% by mass, a large amount of the first binder resin must be charged into the kneader with respect to the colorant, and the colorant segregates in the first kneaded product. In order to bring this into a uniform system, the kneading time must be set long, and the productivity is unfavorable.

  When the ratio of the colorant to the binder resin is more than 60% by mass, the transition of the colorant particles to the first binder resin is not performed smoothly, and the kneaded product is also melted and kneaded after the colorant particles are transferred. Does not show a uniform molten state, and as a result, high dispersibility may not be obtained.

As the binder resin for toner used in the present invention, a known thermoplastic resin can be used. Specific examples are shown below, but are not particularly limited.
For example, styrenes such as styrene, chlorostyrene, and α-methylstyrene; monoolefins such as ethylene, propylene, butylene, and isobutylene; vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, and vinyl butyrate; acrylic acid Esters of α-methylene aliphatic monocarboxylic acids such as methyl, ethyl acrylate, butyl acrylate, octyl acrylate, dodecyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl butyl ether; homopolymers or copolymers of vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropenyl ketone;

Natural and synthetic waxes, polyester resins, polyamide resins, epoxy resins, polycarbonate resins, polyurethane resins, silicone resins, fluorine resins, petroleum resins, and the like can be used, and polyester resins are preferably used.
When a polyester resin is used as the binder resin, those using an alcohol component and a carboxylic acid component such as a carboxylic acid, a carboxylic acid anhydride, or a carboxylic acid ester as raw material monomers can be used.
Specifically, for example, as a divalent alcohol component, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,2-bis ( 4-hydroxyphenyl) propane, polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -polyoxyethylene (2.0) -2,2 -Alkylene oxide adducts of bisphenol A such as bis (4-hydroxyphenyl) propane, polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane, ethylene glycol, diethylene glycol, triethylene glycol, 1, 2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, Opentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A And hydrogenated bisphenol A.
Examples of the trivalent or higher alcohol component include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, etc. Can be mentioned.
Examples of the carboxylic acid component include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid, or anhydrides thereof; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid, or anhydrides thereof; And succinic acid or anhydride thereof substituted with 12 alkyl groups or alkenyl groups; unsaturated dicarboxylic acids such as fumaric acid, maleic acid and citraconic acid or anhydrides thereof.

  Moreover, in order to form the polyester resin which has a bridge | crosslinking site | part, a trivalent or more polyvalent carboxylic acid component can also be used for polyester manufacture. Examples of the trivalent or higher carboxylic acid component include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and 2,5,7-naphthalenetricarboxylic acid. Examples thereof include acids, 1,2,4,5-benzenetetracarboxylic acid, and anhydrides and ester compounds thereof. The amount of the trivalent or higher polyvalent carboxylic acid component is preferably 0.1 to 1.9 mol% based on the total monomer.

  Among the above, as the binder resin, in particular, a bisphenol derivative represented by the following general formula (1) is used as a divalent alcohol component, and a divalent or higher carboxylic acid (for example, fumaric acid, maleic acid, maleic anhydride). Acid, phthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, etc.) or acid anhydrides thereof, or lower alkyl esters thereof as carboxylic acid components, and these polyester resins have good charging characteristics. preferable.

  In the present invention, it is also preferable to use a hybrid resin as the binder resin. The hybrid resin means a resin in which a vinyl polymer unit and a polyester resin unit are chemically bonded. Specifically, a polyester resin unit and a vinyl polymer unit obtained by polymerizing a monomer having a carboxylic acid ester group such as (meth) acrylic acid ester are formed by a transesterification reaction. A graft copolymer (or block copolymer) in which the unit is a trunk polymer and the polyester resin unit is a branch polymer is formed. As the vinyl polymer unit and the polyester resin unit, a vinyl polymer obtained from a vinyl monomer and a polyester resin can be used, respectively.

  In the present invention, the hybrid resin contains a monomer capable of reacting with both in the vinyl polymer and / or polyester resin, and the polymer containing the monomer is present. It is preferable to obtain by carrying out a polymerization reaction. Among the monomers constituting the polyester resin unit, those capable of reacting with the vinyl polymer unit include, for example, unsaturated dicarboxylic acids such as phthalic acid, maleic acid, citraconic acid, and itaconic acid, or anhydrides thereof. . Among the monomers constituting the vinyl polymer unit, those capable of reacting with the polyester resin unit include those having a carboxyl group or a hydroxy group, and acrylic acid or methacrylic acid esters.

The glass transition temperature (Tg) of the first and second binder resins used in the present invention is preferably 40 to 90 ° C, more preferably 45 to 85 ° C.
The binder resin used in the present invention is gel permeation chromatography (GPC).
The molecular weight distribution measured by (1) has a main peak (Mp) in the region of molecular weight 3,500 to 30,000, particularly in the region of molecular weight 5,000 to 20,000, and Mw / Mn is It is preferably 5.0 or more. When the main peak is in a region having a molecular weight of 3,500 or more, the hot offset resistance of the toner is sufficient. On the other hand, when the main peak is in the region of a molecular weight of 30,000 or less, sufficient low-temperature fixability of the toner can be obtained, and application to high-speed fixing becomes possible. Moreover, when Mw / Mn is 5.0 or more, good offset resistance can be obtained.

In the method for producing a toner of the present invention, the toner raw material mixture may contain one or more kinds of waxes as a release agent, and examples thereof include the following. Low molecular weight polyethylene, low molecular weight polypropylene, low molecular weight olefin copolymer, aliphatic hydrocarbon wax such as microcrystalline wax, Fischer-Tropsch wax, paraffin wax; oxide of aliphatic hydrocarbon wax such as oxidized polyethylene wax; fat Block copolymer of aromatic hydrocarbon wax; wax mainly composed of fatty acid ester such as carnauba wax, montanic acid ester wax, behenyl behenate; and part or all of fatty acid ester such as deoxidized carnauba wax What you did.
In addition, a partially esterified product of a fatty acid such as behenic acid monoglyceride and a polyhydric alcohol; a methyl ester compound having a hydroxyl group obtained by hydrogenating vegetable oil and the like, and the like are also used as a release agent. Particularly preferably used waxes as a release agent are paraffin wax, polyolefin wax, Fischer-Tropsch wax, carnauba wax and the like.
The amount of the wax used in the present invention is 1 to 10 parts by weight, preferably 2 to 8 parts by weight, based on 100 parts by weight of the binder resin in the toner. When the amount is 1 part by mass or more, the toner comes out on the surface of the toner at the time of melting and exhibits releasability. On the other hand, when the amount is 10 parts by mass or less, the amount of wax in the toner becomes suitable, and inferior transparency and charging characteristics can be prevented.

  The toner obtained by the production method of the present invention has one or a plurality of endothermic peaks in the temperature range of 30 to 200 ° C. in the endothermic curve in differential thermal analysis (DSC) measurement. The temperature of the endothermic peak is preferably 60 ° C. to 110 ° C., more preferably 70 ° C. to 90 ° C. When the temperature of the maximum endothermic peak is 60 ° C. or higher, the blocking characteristics tend to be excellent, and when it is 110 ° C. or lower, low-temperature fixing desired from the viewpoint of energy saving is sufficiently facilitated, and a load requiring pressure is not required even in the fixing configuration. Because.

In the toner of the present invention, a charge control agent of an organometallic compound described below can be used as a toner raw material mixture in the second kneading step. The charge control agent for the organometallic compound is preferably an aromatic carboxylic acid derivative selected from an aromatic oxycarboxylic acid and an aromatic alkoxycarboxylic acid, and a metal compound of the aromatic carboxylic acid derivative. Divalent or higher valent metal atoms are preferred. As divalent ^{metal, Mg 2+, Ca 2+, Sr} 2+, Pb 2+, Fe 2+, Co 2+, Ni 2+, Zn 2+, Cu 2+ , and the like, in particular Zn ²⁺ , Ca ²⁺ , Mg ²⁺ and Sr ²⁺ are preferred. Examples of the trivalent or higher metal include Al ³⁺ , Cr ³⁺ , Fe ³⁺ , Ni ³⁺ and Zr ⁴⁺ . Among these metals, Al ³⁺ and Cr ³⁺ are preferable, and Al ³⁺ and Zr ⁴⁺ are particularly preferable. Specifically, an aluminum compound of di-tert-butylsalicylic acid is particularly preferable as the charge control agent.

The charge control agent used in the present invention is used in an amount of 0.2 to 10 parts by weight, preferably 0.3 to 7 parts by weight, based on 100 parts by weight of the binder resin in the toner. 0.
When the amount is 2 parts by mass or more, an effect of rising of the charge is obtained, and when the amount is 10 parts by mass or less, environmental fluctuation is reduced.

In the present invention, it is preferable for improving the image quality that a fluidity improver is externally added to the toner particles as an external additive in the step of externally adding the external additive. The fluidity improver is an agent that can be added to the toner particles to increase the fluidity before and after the addition.
Examples of the fluidity improver include fluorine resin powders such as vinylidene fluoride fine powder and polytetrafluoroethylene fine powder; silica fine powder such as silica fine powder by a wet process, silica fine powder such as silica fine powder by a dry process; Treated silica fine powder whose powder is surface-treated with a treatment agent such as silane coupling agent, titanium coupling agent, silicone oil, etc .; titanium oxide fine powder; alumina fine powder, treated titanium oxide fine powder, treated alumina oxide fine powder, etc. Is mentioned.

A fluidity improver having a specific surface area of 30 m ² / g or more, more preferably 50 m ² / g or more, gives good results by nitrogen adsorption measured by the BET method. The fluidity improver is preferably added in an amount of 0.01 to 8 parts by weight, more preferably 0.1 to 4 parts by weight, based on 100 parts by weight of the toner particles.
As described above, the external addition of the fluidity improver is performed by sufficiently mixing the fluidity improver and the toner particles with a mixer such as a Henschel mixer. By such a mixing operation, a toner having a fluidity improver on the toner particle surface can be obtained.

The toner obtained by the production method of the present invention preferably has a weight average particle diameter of 4 to 10 μm, and more preferably 5 to 9 μm.
When the weight average particle size of the toner is 10 μm or less, it means that there are many fine particles that can contribute to high image quality, and there is a tendency to adhere faithfully on a fine electrostatic charge image on the photosensitive drum. There is a tendency that the reproducibility of the light portion is improved and the resolution is also improved. In addition, there is a tendency to prevent the toner from riding on the electrostatic charge image more than necessary and an increase in toner consumption.
Conversely, when the weight average particle diameter of the toner is 4 μm or more, the charge amount per unit mass of the toner is prevented from being increased, and when used for image formation, the image density is lowered, particularly under low temperature and low humidity. Reduces image density. This is particularly suitable for applications with a high image area ratio such as graphic images. When the thickness is 4 μm or more, contact charging with a charging member such as a carrier is easily performed smoothly, preventing an increase in toner that cannot be sufficiently charged, and preventing fogging due to scattering to a non-image portion. . When the toner has a weight average particle diameter of 4 μm or more, toner self-aggregation hardly occurs, uniform mixing with the carrier is achieved in a short time, and fogging can be prevented in the continuous toner replenishment durability.

In order to make the toner in the present invention have a weight average particle diameter of 4 to 10 μm, the particle diameter is adjusted in the pulverization step, and the toner having a weight average particle diameter in the range may be classified.
The toner produced by the production method of the present invention can be applied to a one-component developer and a two-component developer, and the toner produced in the present invention is not limited to this. When used as an agent, the toner is used mixed with a magnetic carrier. Examples of magnetic carriers include iron or surface-oxidized iron; metal particles such as nickel, copper, zinc, cobalt, manganese, chromium, magnesium, rare earth; alloy particles thereof; oxide particles thereof; ferrites thereof; A coated carrier in which the surface of magnetic particles is coated with a resin; a magnetic particle-dispersed resin carrier in which these magnetic particles are dispersed in resin particles can be used.

  The coated carrier in which the surface of the magnetic particle is coated with a resin is particularly preferable when used in a developing method in which an AC bias is applied to the developing sleeve. As a coating method, a method of adhering a coating solution prepared by dissolving or suspending a resin as a coating material in a solvent to the surface of the magnetic particles, a method of adhering the magnetic particles and the coating material by mixing with powder, etc. Conventionally known methods can be applied.

Examples of the resin as a coating material on the surface of the magnetic particles include silicone resin, polyester resin, styrene resin, acrylic resin, polyamide, polyvinyl butyral, and aminoacrylate resin. These may be used alone or in combination. The treatment amount of the coating material is preferably 0.1 to 30% by mass, more preferably 0.5 to 20% by mass with respect to the magnetic particles.
The 50% average particle diameter of the magnetic carrier is preferably 10 to 100 μm, and more preferably 20 to 70 μm.
When a two-component developer is prepared by mixing the toner produced in the present invention and a magnetic carrier, the mixing ratio is usually preferably 2 to 15% by mass of the toner in the developer. It is preferable for obtaining the result, and more preferably 4 to 13% by mass.

First, the developing method of the present invention will be described in detail.
An example of a developing device using the developing method of the present invention is shown in FIG. The developer T accommodated in the developing container 2 in the developing device 1 is first arranged in the first developing sleeve including the first magnet roll 8 ′ disposed upstream of the rotation direction “a” of the image carrier 10. 8 is carried and conveyed. Then, a developer layer is formed on the surface of the developing sleeve by the developer layer thickness regulating member 9 disposed close to the developing sleeve 8. Thereafter, the developer T is conveyed by the developing sleeve 8 to a first developing area where the developing sleeve 8 and the image carrier 10 are opposed to each other, and is used for development. Thereafter, the developer remaining on the surface of the first developing sleeve is a region where the first developing sleeve 8 and the second developing sleeve 11 disposed on the downstream side in the rotation direction a of the image carrier 10 face each other. It is delivered to the second developing sleeve 11. The developer T transferred to the second developing sleeve 11 is carried and transported by the second developing sleeve 11 and transported to the second developing region where the second developing sleeve 11 and the image bearing member face each other. And subjected to development. Thereafter, the developer remaining on the surface of the second developing sleeve is collected in the developing container 2.

  In the case of a developing method employing such a multi-stage developing system, between the developing sleeve 8 and the developer layer thickness regulating agent 9 (between S and B), between the first developing sleeve 8 and the second developing sleeve 11 (S- (Between S), a compressive force or a shearing force is applied to the developer. In particular, when the rotation direction of the first developing sleeve 8 is the b direction and the rotation direction of the second developing sleeve 11 is the c direction, The shearing force to the developer between S and S becomes very large, and the developer tends to deteriorate.

  In the developing device 100 of FIG. 8, the developing chamber 3 and the agitating chamber 4 in the developing container 2 are arranged in the vertical direction, but functional separation such as supply and recovery of the developer is performed as described above. Is important and is not limited to the arrangement of FIG. In addition, when the developing chamber and the stirring chamber are arranged in the vertical direction, an advantage of downsizing the developing device itself can be obtained.

  FIG. 9 shows an example of the presence state (agent surface state) of the developer T accommodated in the developing container 2 shown in FIG. The circulation direction of the developer T is the d direction. In this case, the developer T is transported to the opening 71 by the screw 6 in the stirring chamber 4 together with the developer collected from the second developing sleeve 11 after passing through the developing region. Lifted and supplied. Further, the developer T that has been lifted is conveyed to the opening 72 by the screw 5 in the developing chamber 3 and dropped into the stirring chamber 4 while being supplied to the first developing sleeve 8 in the developing chamber 3.

  In the case of the developing method using such a circulation system, the developer surface of the developer T is lifted from the stirring chamber 4 to the developing chamber 3 in the opening 71 to facilitate supply, and the supplied developer T is supplied to the developing chamber. The point is to make it easy to be transported within 3. In such a development system, it is required that the developer be hardly deteriorated and easily transported. When the developer deteriorates, the developer stays between S-B and S-S, causing streaks and unevenness in the developer layer and causing a defective image.

<Molecular weight measurement of binder resin>
The column is stabilized in a 40 ° C. heat chamber, and THF as a solvent is allowed to flow through the column at this temperature at a flow rate of 1 ml per minute, and about 100 μl of the THF sample solution is injected and measured. An RI (refractive index) detector is used as the detector. As the column, it is preferable to use a combination of a plurality of commercially available polystyrene gel columns. For example, combinations of shodex GPC KF-801, 802, 803, 804, 805, 806, 807, and 800P manufactured by Showa Denko K.K. TSKgel G1000H (HXL), G2000H (HXL), G3000H (HXL), G4000H (HXL), G5000H (HXL), G6000H (HXL), G7000H (HXL), TSKguard manufactured by Tosoh Corporation
A combination of columns can be given.
The THF sample solution is prepared as follows. Place the sample in THF and let stand for several hours, then shake well, mix well with THF (until the sample is no longer integrated), and let stand for more than 12 hours. At this time, the immersion time in THF is 24 hours or longer. Thereafter, a sample processing filter (pore size 0.2 to 0.5 μm, for example, available from Mysori Disc H-25-2 manufactured by Tosoh Corporation) can be passed to obtain a THF sample solution for GPC. The sample concentration is adjusted so that the resin component is 0.5 to 5 mg / ml.

In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, for example, one having a molecular weight of about 10 ² to 10 ⁷ manufactured by Tosoh Corporation or Showa Denko Co., Ltd., and at least about 10 standard polystyrene samples should be used. Is appropriate.

<Measurement of softening point temperature Tm of binder resin>
For the measurement of the softening point temperature of the binder resin, a flow tester CFT-500 type (manufactured by Shimadzu Corporation) is used. The sample weighs about 1.0 g of a 60 mesh pass product. This sample is pressed with a load of 100 kg / cm ² for 1 minute using a molding machine.

The pressure sample is subjected to flow tester measurement under the following conditions under normal temperature and humidity (temperature of about 20 to 30 ° C., humidity of 30 to 70% RH) to obtain a temperature-apparent viscosity curve. From the obtained smooth curve, the temperature (= T1 / 2) when the sample flows out by 50% by volume is obtained, and this is defined as the softening point temperature Tm of the resin. Also, the resin outflow start temperature Tfb indicates a temperature at which the piston clearly starts to fall again after the piston is slightly raised due to thermal expansion of the sample.
When two or more types of binder resins were used, a sample mixed at a ratio that actually forms a toner was used as a sample.

RATE TEMP 6.0 (° C / min)
SET TEMP 50.0 (° C)
MAX TEMP 180.0 (° C)
INTERVAL 3.0 (° C)
PREHEAT 300.0 (seconds)
LOAD 20.0 (kg)
DIE (Diameter) 1.0 (mm)
DIE (Length) 1.0 (mm)
PLUNGER 1.0 (cm ² )

<Measurement of toner particle size>
In the present invention, the average particle size of the toner is measured using a Coulter Counter TA-II type (manufactured by Beckman Coulter, Inc.), but a Coulter Multisizer (manufactured by Beckman Coulter, Inc.) can also be used. As the electrolytic solution, a 1% NaCl aqueous solution is prepared using primary sodium chloride. For example, ISOTON R-II (manufactured by Coulter Scientific Japan Co., Ltd.) can be used.
As a measuring method, 0.1 to 5 ml of a surfactant, preferably alkylbenzene sulfonate, is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the volume and number of toner particles of 2.00 μm or more are measured by using the 100 μm aperture as the aperture by the measuring device. Distribution and number distribution are calculated. Then, the weight average particle diameter (D4) obtained from the volume distribution according to the present invention (the median value of each channel is used as the representative value for each channel) is obtained.
As channels, 2.00 to 2.52 μm; 2.52 to 3.17 μm; 3.17 to 4.00 μm; 4.00 to 5.04 μm; 5.04 to 6.35 μm; 6.35 to 8. 00 μm; 8.00 to 10.08 μm; 10.08 to 12.70 μm; 12.70 to 16.00 μm; 16.00 to 20.20 μm; 20.20 to 25.40 μm; 25.40 to 32.00 μm; 13 channels of 32.00-40.30 μm are used.

<Measurement of bulk density of raw material mixture>
The bulk density was measured using a measuring instrument (manufactured by Kuramochi Scientific Instruments) in accordance with JISZ2504. Specifically, a sample is put into a 25 cc measuring cup through a funnel until it reaches a heap. A blade is placed vertically on a sample of cups in a pile, and the surface of the sample is worn. The bulk density was calculated from the weight in the measuring cup.

<Measurement method of resin particle size>
The average particle size and particle size distribution of the pulverized resin were determined by combining a laser diffraction particle size distribution measuring device HELOS (manufactured by JEOL) with a dry dispersion unit RODOS (manufactured by JEOL), a lens focal length of 200 mm, a dispersion pressure of 3.0 bar, Measurement is performed by dividing the range of 0.5 μm to 350.0 μm in particle size into 31 channels under measurement conditions of measurement time of 1 to 2 seconds, and 50% particle size (median diameter) of the volume distribution is obtained as an average particle size.

<Measurement of THF-insoluble content of binder resin by Soxhlet extraction>
1.0 g of resin is weighed (W1 g) and cylindrical filter paper (for example, No. 86R size 28 × 100)
mm, manufactured by Toyo Roshi Kaisha, Ltd.), passed through a Soxhlet extractor, and extracted for 16 hours using 200 ml of THF as a solvent. At this time, the extraction is performed at a reflux rate such that the solvent extraction cycle is about once every 4 to 5 minutes. After the extraction is completed, the cylindrical filter paper is taken out and vacuum-dried at 40 ° C. for 8 hours, and the extraction residue is weighed (W2 g).
The THF-insoluble content of the resin is obtained from the following formula.
THF insoluble matter = W2 / W1 × 100 (%)

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this does not limit this invention at all. In addition, “part” representing the blending amount means “part by mass”.

<Manufacture of binder resin>
(Production example of resin 1)
Bisphenol A propylene oxide adduct: 16.0 mol%
Bisphenol A ethylene oxide adduct: 32.0 mol%
Terephthalic acid: 40.0 mol%
Ethylene glycol: 4.0 mol%
Trimellitic acid: 5.0 mol%
Fumaric acid: 15.0 mol%
Acrylic acid: 3.0 mol%
The polyester monomer is charged into a four-necked flask and equipped with a decompression device, a water separation device, a nitrogen gas introduction device, a temperature measurement device, and a stirring device, and stirred at 170 ° C. in a nitrogen atmosphere. A mixture of vinyl polymerization monomer (styrene: 90.0 mol% and 2-ethylhexyl acrylate: 8.0 mol%) and benzoyl peroxide (BPO) 2.0 mol% as a polymerization initiator was dropped from the dropping funnel over 4 hours. did. Then, after reacting at 170 ° C. for 5 hours, the temperature was raised to 240 ° C., 0.3% by mass of dibutyltin oxide (DBO) was added, and a condensation polymerization reaction was performed for 5 hours. After completion of the reaction, it was taken out from the container, cooled and pulverized to obtain a resin 1. Table 2 shows the production conditions of the polyester part of resin 1, the styrene acrylic part, and the resin polymerization method. Table 1 shows the physical properties of Resin 1.
<Production example of resins 2 to 5>
Resins 2 to 5 were obtained in the same manner as in Production Example of Resin 1 using the monomers listed in Table 1 under the production conditions described.

<Example of production of binder resin 1>
Resin 1 and Resin 2 were mixed at a ratio of 50 wt% with a Henschel mixer (manufactured by Mitsui Miike Chemical Co., Ltd.). The resulting mixture was pulverized twice with a micro ACM pulverizer (Hosokawa Micron) at a rotational speed of 5000 rpm to obtain a binder resin 1. Table 2 shows the physical properties of the binder resin 1.

<Example of production of binder resins 2 and 3>
Binder resins 2 and 3 were obtained in the same manner as binder resin 1 except that the resin used was changed. Table 2 shows the physical properties of the binder resins 2 and 3.

<Example of production of binder resin 4>
A binder resin 4 was obtained in the same manner as the binder resin 1 except that the number of times of pulverization was one. Table 2 shows the physical properties of the binder resin 4.

<Example of production of binder resin 5>
A binder resin 5 was obtained in the same manner as the binder resin 4 except that the number of rotations during pulverization was changed to 3000 rpm. Table 2 shows the physical properties of the binder resin 5.

<Example of production of binder resin 6>
Only resin 4 was pulverized once at 3000 rpm, and then mixed with unground resin 1 with a Henschel mixer to obtain binder resin 6. Table 2 shows the physical properties of the binder resin 6.

<Example of production of binder resins 7 and 8>
Binder resins 7 and 8 were obtained in the same manner as binder resin 1 except that the resin used was changed. Table 2 shows the physical properties of the binder resins 7 and 8.

<Example of production of binder resin 9>
Binder resin 1 was further pulverized by jet mill pulverization to obtain binder resin 9. Table 2 shows the physical properties of the binder resin 9.

<Example of production of binder resin 10>
The binder resin 10 was obtained with the binder resin 1 in an unground state. Table 2 shows the physical properties of the binder resin 10.

表中、「ＡＣＭ２パス」はマイクロACMパルベライザにて2回粉砕を行ったことを示す。

In the table, “ACM2 pass” indicates that pulverization was performed twice with a micro ACM pulverizer.

<Production example of coat carrier>
Magnetic fine particle dispersed cores were produced using the materials shown below.
・ Phenol 10.0 mass parts ・ Formaldehyde solution (37 mass% aqueous solution) 4.0 mass parts ・ Magnetite particles (number average particle diameter D1 = 0.28 μm, magnetization strength 75 Am ² / kg, specific resistance 5.5 × 10 ⁵ Ω) cm) 86.0 parts by mass The above materials, 5.0 parts by mass of 28% by mass ammonia water, and 10.0 parts by mass of water were placed in a flask, and the temperature was raised to 90 ° C. in 30 minutes while stirring and mixing. Cured. Then, after cooling to 30 ° C. and further adding water, the supernatant was removed, and the precipitate was washed with water and then air-dried. Next, this was dried under reduced pressure (5 hPa or less) at a temperature of 60 ° C. to obtain a magnetic fine particle dispersed core in which the magnetic fine particles were dispersed.
Subsequently, 5.0 parts by weight of methyl methacrylate macromer having an ethylenically unsaturated group at one end and a weight average molecular weight of 4,500, 50.0 parts by weight of methyl methacrylate, 50.0 parts by weight of cyclohexyl methacrylate, reflux condenser, thermometer, nitrogen suction pipe and Add to a four-necked flask equipped with a rubbing method stirrer, add 100.0 parts by mass of toluene, 100.0 parts by mass of methyl ethyl ketone, and 2.5 parts by mass of azobisisovaleronitrile, and keep at 80 ° C. for 10 hours under a nitrogen stream. A resin solution for materials (solid content: 35% by mass) was obtained.
1.5 parts by mass of silicone particles (number average particle size 0.2 μm), carbon black (number average particle size 30 nm, DBP oil absorption 40 ml / 1) with respect to 30.0 parts by mass of the resulting resin solution for coating material
00 g) 1.5 parts by mass and 70.0 parts by mass of toluene were dispersed in a bead mill (RMH-03 type, manufactured by Imex Corp.) using glass beads having a bead diameter of 0.5 mm to obtain a coating material.
Subsequently, 6 parts by mass of the coating material was sprayed with a spray nozzle while flowing 100 parts by mass of the magnetic fine particle dispersed core at 85 ° C. using a fluidized bed coating apparatus (Spiraflow, manufactured by Freund Sangyo Co., Ltd.). Thereafter, the solvent was volatilized and dried at 110 ° C. while flowing to coat the core surface. The coated magnetic fine particle-dispersed core has an opening of 75 μm.
m sieve, average particle size 40 μm, specific resistance 5.0 × 10 ⁸ Ω · cm, true specific gravity 3.5 g / cm ³
A coated carrier having a magnetization strength (σ1000) of 52.5 Am ² / kg and a residual magnetization of 5.1 Am ² / kg was obtained.

Subsequently, a toner for evaluation was produced using the following materials and production method.
Binder resin 1 (resin 1: resin 4 = 50: 50, resin particle size 20 μm) 100 parts by mass Pigment Yellow 74 7.0 parts by mass Paraffin wax (melting point 75 ° C.) 5 parts by mass 3,5-di- t-Butyl salicylate aluminum compound 0.5 part by mass In addition to the above materials, 5 wt% of water was added to the amount of the raw mixture, and then mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). Furthermore, the raw mixture was melt-kneaded with a twin-screw extruder (PCM-70 type, manufactured by Ikegai Seisakusho). In the PCM-70 used at this time, the length L of the kneading and melting part was 900 mm, and the ratio L / D between the length of the melting part and the diameter of the kneading shaft was 12.9. The barrel setting temperature Ta of the kneading part was 95 ° C., the rotational speed of the kneading shaft was 400 rpm, and 10 L / min of cooling water was allowed to flow inside the main shaft for cooling the main shaft. Furthermore, the obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized toner. The obtained toner coarsely pulverized product was finely pulverized using a mechanical pulverizer (Turbo Mill Turbo Industry Co., Ltd.). At this time, a sample was extracted as a finely pulverized product.
Binder resin 1 (resin 1: resin 4 = 50: 50, resin particle size 20 μm) 100 parts by mass Pigment Yellow 74 7.0 parts by mass Paraffin wax (melting point 75 ° C.) 5 parts by mass 3,5-di- t-Butyl salicylic acid aluminum compound 0.5 parts by mass-Finely pulverized product extracted above 20 parts by mass

In addition to the above materials, 5 wt% of water was added to the amount of the raw mixture, and then mixed with a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). The bulk density of the raw mixture obtained at that time was 0.38 g / cm ³ . Further, the raw mixture was kneaded under the same conditions using the above twin screw extruder. At that time, the production tact in the kneading process was measured. As a method, the raw mixture is supplied to the kneader from the material supply port of FIG. At that time, the feed amount was 350 kg / h as the upper limit, and the feed amount that was stably discharged from the extrusion port for 30 minutes was defined as the production tact. Incidentally, the feed amount at this time was 250 kg / h, which was a sufficient production tact amount. Furthermore, the obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized toner. The obtained toner coarsely pulverized product was finely pulverized using a mechanical pulverizer (Turbo Mill Turbo Industry Co., Ltd.). Thereafter, surface modification and classification were simultaneously performed with the surface modification apparatus shown in FIG. 6 to obtain a toner classified product.
The obtained toner classified product 100 parts by mass 1.0 parts by mass of anatase type titanium oxide having a BET specific surface area of 100 m ² / g, hydrophobic silica having a BET specific surface area of 130m ² / g 1.
0 parts by mass was added and mixed with a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.) to obtain evaluation toner 1. The obtained toner 1 had a weight average particle diameter (D4) of 6.5 μm. Table 2 shows the manufacturing conditions.
A developer was prepared using toner 1 and a coat carrier. To 90 parts by mass of the coated carrier, 10 parts by mass of toner 1 was added and mixed for 5 minutes with a V-type mixer to obtain a developer.

As an image forming apparatus, a Canon color copier imagePRESS C7000VP was used. The developing unit used in this product employs a twin sleeve developing system as shown in FIG. Further, the copying machine was remodeled so as to be able to output under the following conditions, the developer was put in each color developing device, and various evaluations were performed before and after the durability test of 100,000 images having an image area ratio of 10% under the following conditions.
conditions:
Printing environment Temperature 30 ° C / Humidity 80RH% (hereinafter “H / H”)
Temperature 23 ° C / Humidity 5RH% (hereinafter “N / L”)
Paper 1 Color laser copier paper (81.4 g / m ² )
Paper 3 Color Laser Copier Glossy Cardboard NS-701 (150 g / m ² )
(Both are Canon Marketing Japan Inc.)
Development conditions Modified so that development contrast can be changed freely.
Developer idle rotation The sleeve peripheral speed of the main unit developer was changed freely, and it was modified to allow idle rotation.

<Fog (after endurance)>
After the endurance, an A4 full solid white image was output with color laser copier paper. The fog was measured with a reflectometer (manufactured by Tokyo Denshoku Co., Ltd.), and the fog density (%) was calculated and evaluated from the difference between the whiteness and the whiteness of the transfer paper. The evaluation criteria are as follows. A: Very good (less than 0.5%)
B: Good (0.5% or more and less than 1.0%)
C: Slightly good (1.0% or more, less than 1.5%)
D: Normal (1.5% or more, less than 2.5%)
E: Slightly bad (2.5% or more, less than ~ 3.0%)
F: Poor (3.0% to 4.0%)
G: Very bad (over 4.0%)
The levels that are not problematic as products are A to D.

<Evaluation of brightness L * (after idling of developer)>
N / L for each developer in which the two-component developer is charged in a state where the developer for replenishment is not replenished
It was idled in the environment and H / H environment. The peripheral speed of the sleeve during idling was 700 mm / sec, and the process of idling for 1 hour and then stopping for 10 minutes was repeated for idling for a total of 20 hours. Thereafter, the development contrast was adjusted so that the amount of toner on the paper was 0.55 mg / cm ^2, and an A4 full-color image was output with color laser copier paper. Thereafter, the lightness L * before and after durability was measured with the following measuring instrument and measurement conditions.
The lightness L * is determined by SpectroScan Transmission (GretagMac
It is calculated | required by measuring using a product made by beth. An example of specific measurement conditions is shown below.
<Measurement conditions>
Observation light source: D50
Observation field: 2 °
Concentration: DIN NB
White standard: Pap
Filter: None
The evaluation criteria were as follows.
A: Very good 83.0 or more B: Good 82.0 or more, less than 83.0 C: Somewhat good 81.0 or more, less than 82.0 D: Normal 80.0 or more, less than 81.0 E: Somewhat bad 78.0 or more, less than 80.0 F: Poor 76.0 or more, less than 78.0 G: Very bad, less than 76.0 In addition, the level which is satisfactory as a product is A thru | or D.

<Evaluation of low-temperature fixability>
For fixing performance evaluation, a belt fixing device as shown in FIG. 10 was used. As fixing conditions, the fixing speed is 250 mm / sec, the fixing nip width is 30 mm, and the fixing nip pressure is 0.15 MPa.
It was.
First, an A4 image (printing ratio: 20%) as shown in FIG. 11 and 105 g / m ² paper were used as the recording material. An image was output while adjusting the development bias so that the amount of toner applied on the recording material was 1.2 mg / cm ² . The obtained image was conditioned for 24 hours in an N / N (23 ° C./60%) environment.
Subsequently, the low temperature fixability of the toner was evaluated in an N / N environment. Using the conditioned image, paper was passed while the temperature of the fixing belt was raised by 5 ° C. in the range of 100 to 200 ° C. The image that was passed through the paper was folded and opened in a cross by reciprocating a cylindrical roller (brass: 798 g) of φ60 mm × 40 mm five times, and then a 22 mm × 22 mm × 47 mm square column weight (made of brass) : 198 g), a section of Sylbon paper (Dasper K3-half cut, manufactured by Ozu Sangyo Co., Ltd.) was wound and rubbed 10 times, and the temperature at which the toner image peeling rate was 25% or less was defined as the fixing temperature. An image processing system (Personal IAS) was used for the measurement of the peeling rate.

<Evaluation of hot offset property>
For fixing performance evaluation, a belt fixing device as shown in FIG. 10 was used. The fixing conditions were a fixing speed of 250 mm / sec, a fixing nip width of 30 mm, and a fixing nip pressure of 0.15 MPa.
First, an A4 image (printing ratio: 15%) as shown in FIG. 12 and a recording material of 64 g / m ² paper were used. An image was output while adjusting the developing bias so that the amount of toner applied on the recording material was 0.2 mg / cm ² . The obtained image was conditioned for 24 hours in an N / N (23 ° C./60%) environment.
Subsequently, the hot offset property of the toner was evaluated in an N / N environment. Using the conditioned image, paper was passed while the temperature of the fixing belt was increased by 5 ° C. in the range of 120 to 220 ° C. The fogged density measurement was performed on the passed image in an area other than the toner image portion. For the fog density measurement, a reflection densitometer (TC-6DS, manufactured by Tokyo Denshoku Co., Ltd.) is used, and the temperature at which (maximum value of reflection density) − (minimum value of reflection density) is 0.5 or less, It was judged that the temperature was satisfactory for hot offset property, and is listed in Table 4.

<Evaluation of reflection density>
For fixing performance evaluation, a belt fixing device as shown in FIG. 10 was used. The fixing conditions were a fixing speed of 250 mm / sec, a fixing nip width of 30 mm, and a fixing nip pressure of 0.15 MPa.
An A4 image (printing ratio: 20%) as shown in FIG. 11 and a recording material of 80 g / m ² paper were used. An image was output while adjusting the developing bias so that the amount of toner applied on the recording material was 0.55 mg / cm ² . The obtained image was conditioned for 24 hours in an N / N environment. Using the conditioned image, the reflection belt density was measured using an image passed through at a temperature at which the fixing belt had the highest gloss in the evaluation of low-temperature fixability. The obtained image was subjected to 6 reflection density measurements with a reflection densitometer X-Rite500, and evaluated according to the following criteria.
A: The reflection density value is 1.45 or more. B: The reflection density value is 1.40 or more and less than 1.45.
C: The reflection density value is 1.35 or more and less than 1.40.
D: Reflection density value is less than 1.35 (practical level).

  In Example 1, each evaluation showed very good image characteristics. The results are shown in Table 4.

[Example 2] to [Example 7]
As shown in Table 3, each evaluation was performed in the same manner as in Example 1 except that the barrel set temperature of the kneading part and the binder resin were changed.

[Example 8] to [Example 12]
As shown in Table 3, each evaluation was performed in the same manner as in Example 1 except that the length of the melted portion, the diameter of the kneading shaft, and the cooling water did not flow inside the kneading shaft.

[Example 13] to [Example 15]
As shown in Table 3, each evaluation was performed in the same manner as in Example 1 except that the mass part of the finely pulverized product mixed with the binder resin was changed.

[Example 16]
-Binder resin 6 100 parts by mass-Pigment Yellow 74 7.0 parts by mass-Paraffin wax (melting point 75 ° C) 5 parts by mass-3,5-di-t-butylsalicylic acid aluminum compound 0.5 parts by mass In addition, 5 wt% of water was added to the amount of the raw mixture, and then mixed with a Henschel mixer (manufactured by Mitsui Miike Chemical Co., Ltd.). The bulk density of the raw mixture obtained at that time was 0.49 g / cm ³ . Furthermore, the raw mixture was melt-kneaded with a twin-screw extruder (PCM-70 type, manufactured by Ikegai Seisakusho). In the PCM-70 used at this time, the length L of the kneading and melting part was 900 mm, and the ratio L / D between the length of the melting part and the diameter of the kneading shaft was 12.9. The barrel setting temperature Ta of the kneading part was 95 ° C., the rotational speed of the kneading shaft was 400 rpm, and 10 L / min of cooling water was allowed to flow inside the main shaft for cooling the main shaft. Furthermore, the obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized toner. The obtained toner coarsely pulverized product was finely pulverized using a mechanical pulverizer (Turbo Mill Turbo Industry Co., Ltd.). Thereafter, surface modification and classification were simultaneously performed with the surface modification apparatus shown in FIG. 6 to obtain a toner classified product.
The obtained toner classified product 100 parts by mass 1.0 parts by mass of anatase type titanium oxide having a BET specific surface area of 100 m ² / g, hydrophobic silica having a BET specific surface area of 130m ² / g 1.
0 parts by mass was added and mixed with a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.) to obtain evaluation toner 1. The obtained toner 1 had a weight average particle diameter (D4) of 6.5 μm. Table 2 shows the manufacturing conditions.
A developer was prepared using toner 1 and a coat carrier. To 90 parts by mass of the coated carrier, 10 parts by mass of toner 1 was added and mixed for 5 minutes with a V-type mixer to obtain a developer. The evaluation results are shown in Table 4.

[Example 17] to [Example 21]
As shown in Table 3, each evaluation was performed in the same manner as in Example 16 except that the amount of water added to the binder resin and the raw mixture, the barrel temperature of the kneading part, and whether or not the kneading shaft was cooled were changed. Went.

[Example 22] to [Example 23]
As shown in Table 3, each evaluation was performed in the same manner as in Example 16 except that the binder resin, the length of the melt-kneading part, the barrel temperature, and whether or not the kneading shaft was cooled were changed.

[Comparative Example 1] to [Comparative Example 2]
As shown in Table 3, each evaluation was performed in the same manner as in Example 17 except that the barrel temperature of the kneading part was changed.
In Comparative Example 1, since the barrel set temperature was high, charge-up occurred, fogging deteriorated, and the level was NG.
In Comparative Example 2, since the barrel set temperature was low, the dispersibility of the colorant was deteriorated and the coloring power was lowered to be NG level.

[Comparative Example 3] to [Comparative Example 4]
As shown in Table 3, each evaluation was performed in the same manner as in Example 17 except that the barrel temperature of the binder resin and the kneading part was changed.
In Comparative Example 3, since the softening point of the binder resin was low, the hot offset property and fogging in the HH environment were at the NG level.
In Comparative Example 4, since the softening point of the binder resin was high, the low-temperature fixability was NG level.

[Comparative Example 5] to [Comparative Example 8]
As shown in Table 3, each evaluation was performed in the same manner as in Example 17 except that the length and diameter of the melted part and the presence or absence of cooling of the kneading shaft were changed.

[Comparative Example 9] to [Comparative Example 10]
As shown in Table 3, each evaluation was performed in the same manner as in Example 17 except that the resin was changed.
In Comparative Example 9, since the bulk density of the raw mixture was low, the bite into the kneading machine was poor, and the production tact was NG level.

[Comparative Example 11]
As shown in Table 3, Example 1 except that the colorant is changed to Pigment Yellow 17
Each evaluation was performed in the same manner as above.

Claims (4)

In a production method for obtaining a toner by melt-kneading a raw material mixture containing at least a binder resin and a colorant using an extruder,
i) The binder resin has a softening point Tm (° C) of 80 ° C or higher and 140 ° C or lower,
ii) The extruder has a biaxial extrusion type in which the melt-kneading shaft is in the same direction, the length (L) of the melted portion of the melt-kneading shaft is not less than 550 mm and not more than 1500 mm, and the diameter (D) of the melt-kneading shaft is Ratio (L / D) is 10.0 or more and 20.0 or less,
iii) Barrel setting temperature Ta (° C.) of the kneading part of the melt-kneading shaft, softening point Tm of the binder resin
(° C.) and the outflow start temperature Tfb (° C.) of the binder resin are Tfb ≦ Ta ≦ Tm,
iv) A method for producing a toner, wherein the raw material mixture has a bulk density of 0.20 g / cm ³ or more and 0.50 g / cm ³ or less.   The method for producing a toner according to claim 1, wherein water is added to the raw material mixture, followed by melt-kneading.   3. The toner production method according to claim 1, further comprising a cooling unit inside the melt-kneading shaft.   The method for producing a toner according to claim 1, wherein the colorant contains a monoazo pigment.

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