JP2010134253A - Method for manufacturing toner particle and manufacturing apparatus for toner particle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a toner and a manufacturing apparatus which stably obtain toner surface-modified particles having a small particle diameter and a sharp particle size distribution with less fine powder and having a high circularity in a preferable yield, and further, to provide a method for manufacturing a toner and a manufacturing apparatus for the toner showing good developability, transfer property, cleaning property and stable chargeability even in long-term use and having a long life and resistance against stresses such as heat and impact. <P>SOLUTION: A surface-modifying device is used and includes a classifying means, a surface modifying means carrying out surface modification of toner particles by using mechanical impact force, and a guiding means; the surface modifying means includes a rotor 32 and a stator 34 disposed as keeping a given distance from an outer rim of the rotator in a horizontal direction from the rotator; the rotator has a plurality of hammers on the outer rim; the stator has a single or a plurality of grooves on the surface opposing to the rotator; and the gradient θ1 of the groove in the circumference direction gives an angle of 60 degrees to 90 degrees with respect to the rotational axial line of the rotor, along the rotation direction of the rotor. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a toner particle manufacturing method and a toner particle manufacturing apparatus used in an image forming method such as an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or a toner jet recording method.

  In an image forming method such as electrophotography, a toner for developing an electrostatic image is used. The toner production method is roughly classified into a pulverization method and a polymerization method, and a simple and popular production method includes a pulverization method. As a general manufacturing method thereof, a binder resin for fixing to a transfer material, a colorant for giving a color as a toner is used, and a charge control agent for imparting electric charges to particles as necessary, A magnetic material for imparting transportability and the like to the toner itself, and additives such as a release agent and a fluidity imparting agent are added and mixed. And after melt-kneading and cooling and solidifying, the kneaded material is refined | miniaturized by a grinding | pulverization means, and if necessary, it classifies to a desired particle size distribution, Furthermore, a fluidizing agent etc. are added. In the case of the toner used in the two-component development method, it is used after mixing various magnetic carriers and the toner.

  Various pulverizers are used as the pulverizer, and mechanical pulverizers are used as pulverizers that are energy efficient (see, for example, Patent Document 1 and Document 2). This mechanical crusher grinds by introducing a powder raw material into an annular space formed between a rotor rotating at high speed and a stator arranged around the rotor.

  For this reason, the toner particles pulverized by the mechanical pulverizer have a specific surface area smaller than that of the toner particles pulverized by the jet airflow pulverizer because the particles collide with the walls of the rotor and stator rotating at high speed. Become. Therefore, the fluidity is good and the voids are small, so that there is an advantage that the filling property is excellent and the addition amount of the external additive is small. In addition, there are merits in quality such as excellent chargeability and transferability. That is, according to the mechanical pulverizer, it is possible to produce toner of excellent quality with energy saving and high yield.

However, in recent years, the print on demand (POD) market has attracted attention, and the performance required of toner as a developer has become more severe with the increase in image quality and definition of copiers and printers. In the POD market for image forming methods based on electrophotography, there is a long-awaited toner that achieves high-resolution and high-definition images when used for a long period of time, and does not impair image color gamut, saturation, and brightness, and stably expresses good image quality. Has been. For this reason, the toner is required to have a sharp particle size distribution with a small particle size and a small amount of fine powder. In addition, the surface composition of the toner is difficult to change due to stress such as heat and impact. In particular, it is desired to suppress the change in the presence state of the wax component as much as possible to prevent the carrier from being contaminated and to maintain high developability even during long-term use.
Furthermore, in order to achieve cleaner-less and waste toner reduction, improvement in toner transferability is required, so that further spheroidization to improve the surface shape of toner particles has been required. Yes.

  For example, as a method for producing the toner described above, a toner that has been spheroidized by a mechanical impact force has been proposed (see, for example, Patent Document 3). In addition to the method using the mechanical impact force described above, a method for melting the surface with hot air, a method using heat, and the like are known as methods for making the toner shape spherical (see, for example, Patent Document 4). ).

However, in the method using the mechanical impact force, when the toner is easily pulverized, particularly when the toner is spheroidized, the toner is pulverized due to the impact caused by the spheronization, and the amount of fine powder increases. Yes, it is not preferable in terms of toner productivity and quality. In the method of melting the surface by heat, the composition of the toner surface may change. In particular, since the presence state of the wax component added as a release agent changes, it may be undesirable in terms of toner quality.

Thus, since the toner requires many different properties, the properties of the toner are often influenced by the method of producing the toner in addition to the raw materials used.
JP 59-24855 A JP 59-105853 A Japanese Patent Laid-Open No. 9-85741 JP 2000-29241 A

The object of the present invention is to eliminate such problems, and to produce toner surface modified particles having a small particle size, a sharp particle size distribution with few fine powders, and a high degree of circularity, in a high yield, It is an object of the present invention to provide a toner particle manufacturing method and a manufacturing apparatus that can be stably obtained.
Furthermore, in order to obtain a long-life toner having good developability, transferability, cleaning properties, and stable chargeability even during long-term use, a method and apparatus for producing toner particles resistant to stress such as heat and impact Is to provide.

As a result of intensive studies, the present inventors have found that the above requirements can be satisfied by adopting the configuration of the present invention described below, and have reached the present invention.
[1] In a production method having a toner particle or toner surface modification step containing at least a binder resin, a wax and a colorant,
The surface modification step is performed using a surface modification device, and the surface modification device includes a classifying means for continuously discharging and removing fine powder having a particle size of at least a predetermined particle size outside the device, and mechanical impact. Surface modifying means for modifying the surface of the toner particles using force, and guide means for partitioning a space between the classification means and the surface modifying means into a first space and a second space. And
The surface modification means has at least a rotor, and a stator disposed at a constant interval in the horizontal direction from the outer edge of the rotor.
The rotor has a plurality of hammers on its outer edge;
The surface of the stator facing the rotor is provided with one or more grooves, and the one or more grooves have a circumferential inclination of the groove, and the axis of rotation of the rotor On the other hand, the toner particle manufacturing method is characterized in that an angle of 60 degrees or more and 90 degrees or less is formed in the rotation direction of the rotor.
[2] The length A (mm) of the hammer in the rotation axis direction of the rotor and the length B (mm) of the stator in the direction of the rotation axis are 2.0 ≦ B / A ≦ 15. The toner particle production method according to [1], wherein the relationship of 0.0 is satisfied.
[3] Classification means for continuously discharging and removing fine powder having a predetermined particle diameter or less to the outside of the apparatus, surface modification means for modifying the surface of toner particles or toner using a mechanical impact force, and the classification means An apparatus for producing toner particles, having guide means for partitioning a space between the surface modification means and a first space into a first space,
The surface modification means has at least a rotor, and a stator disposed at a constant interval in the horizontal direction from the outer edge of the rotor.
The rotor has a plurality of hammers on its outer edge;
The surface of the stator facing the rotor is provided with one or a plurality of grooves, and the grooves have a circumferential inclination of the grooves with respect to the rotation axis of the rotor. An apparatus for producing toner particles, wherein an angle of 60 degrees or more and 90 degrees or less is formed in the rotation direction of the rotor.
[4] The length A (mm) of the hammer in the rotation axis direction of the rotor and the length B (mm) of the stator in the rotation axis direction are 2.0 ≦ B / A ≦ 15. The toner particle manufacturing apparatus according to [3], wherein the relationship of 0.0 is satisfied.

According to the present invention, it is possible to obtain toner particles that are surface modified particles having a high degree of circularity from which fine powder having a small particle size and a predetermined particle size or less are removed with high yield.
Furthermore, in order to obtain a long-life toner having good developability, transferability, cleaning properties, and stable chargeability even during long-term use, a method and apparatus for producing toner particles resistant to stress such as heat and impact Provided.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments.
First, the production method of the present invention has a surface modification step for toner particles or toner, and a surface modification device used in the surface modification step will be described in more detail with reference to schematic drawings.

  The surface reforming apparatus used in the present invention performs surface modification of toner particles or toner by using a classifying means for continuously discharging and removing fine powder having a predetermined particle size or less to the outside of the apparatus and mechanical impact force. The surface modifying device includes a surface modifying unit, and a guiding unit that partitions a space between the classifying unit and the surface modifying unit into a first space and a second space. Can be used.

  1 includes a cylindrical main body casing 30, a top plate 43 installed to be openable and closable at the top of the main body casing; a fine powder discharge portion 44 having a fine powder discharge casing and a fine powder discharge pipe; cooling water Alternatively, a cooling jacket 31 capable of passing an antifreeze liquid; a disc-like rotating body that is attached to the central rotating shaft in the main body casing 30 and has a plurality of hammers 33 on its outer edge and rotates at a high speed in a predetermined direction. , A rotor 32 as surface modification means; fixedly arranged at a certain distance in the horizontal direction from the outer edge of the rotor 32, and one or a plurality of grooves are formed on the surface facing the rotor 32. Stator 34 provided; Classification rotor 35 for continuously removing fine powder having a predetermined particle size or less in the finely pulverized product and ultrafine powder; Cool air introduction for introducing cool air into the main body casing 30 46; a charging pipe having a raw material charging port 37 and a raw material supplying port 39 formed on the side surface of the main casing 30 for introducing the finely pulverized product (raw material); and toner particles after the surface modification treatment outside the main casing 30 A product discharge pipe having a product discharge port 40 and a product extraction port 42 for discharging; an openable and closable raw material installed between the raw material input port 37 and the raw material supply port 39 so that the surface modification time can be freely adjusted A supply valve 38; and a product discharge valve 41 installed between the product discharge port 40 and the product extraction port 42.

The classifying rotor 35 shown in FIG. 1 is preferably rotated in the same direction as the rotation direction of the rotor 32 in order to increase the efficiency of classification and the efficiency of surface modification of toner particles. If the rotation directions of the rotor and the classification rotor are reversed, the load on the classification rotor increases, and normal operation cannot be performed and the toner productivity is not satisfactory.
The fine powder discharge pipe has a fine powder discharge port 45 for discharging fine powder and ultrafine powder removed by the classification rotor 35 to the outside of the apparatus.

FIG. 2A shows a horizontal projection of the classification rotor, and FIG. 2B shows a sectional view of the classification rotor.
As shown in FIGS. 3A and 3B, the number of hammers 33 is preferably an even number in consideration of rotational balance.

The surface of the stator 34 facing the rotor 32 has one or more grooves as shown in FIGS. 5 (a) and 5 (b). The circumferential inclination of the groove is not less than 60 degrees and not more than 90 degrees in the rotation direction of the rotor with respect to the rotation axis of the rotor 32 (represented by θ1 in FIGS. 5A and 5B). ).
4A and 4B, the surface modifying apparatus further includes a cylindrical guide ring 36 as a guide means having a shaft perpendicular to the top plate 43 in the main body casing 30. As shown in FIG. Have. The upper end of the guide ring 36 is provided at a predetermined distance from the top plate, and is fixed to the main body casing 30 by a support so as to cover at least a part of the classification rotor 35. The lower end of the guide ring 36 is provided at a predetermined distance from the hammer 33 of the rotor 32. In the surface modification apparatus, the space between the classification rotor 35 and the rotor 32 is divided into a first space 47 outside the guide ring 36 and a second space 48 inside the guide ring 36 by the guide ring 36. Divided into two. The first space 47 is a space for guiding the finely pulverized product and the surface-modified particles to the classification rotor 35, and the second space guides the finely pulverized product and the surface-modified particles to the rotor. It is a space for. A gap between the plurality of hammers 33 arranged on the rotor 32 and the stator 34 is a surface modification zone 49, and a classification rotor 35 and a peripheral portion of the classification rotor 35 are a classification zone 50.

Next, an outline of the surface modification method using the surface modification apparatus of the present invention will be described with reference to FIG.
As shown in FIG. 7, the surface reforming apparatus configured as described above is configured so that the finely pulverized product introduced into the raw material hopper 380 is supplied from the raw material input port 37 of the input pipe via the quantitative feeder 315. The material is supplied from the raw material supply port 39 through the supply valve 38. In the surface reformer, the cool air generated by the cool air generating means 319 is supplied from the cool air inlet 46 into the main body casing. Furthermore, the cold water from the cold water generating means 320 is supplied to the cold water jacket 31 to adjust the temperature in the main body casing to a predetermined temperature. The finely pulverized product supplied is supplied to the outer side of the cylindrical guide ring 36 by the amount of suction air by the blower 364, the rotation of the rotor 32 and the rotation of the classification rotor 35, and the swirl flow formed by the grooves of the stator 34. The classifying process is performed by reaching the classification zone 50 near the classification rotor 35 while turning in one space 47. The direction of the swirl flow formed in the main body casing 30 is the same as the rotation direction of the rotor 32 and the classification rotor 35.

  Fine powder and super fine powder to be removed by the classifying rotor 35 are sucked from the slit (see FIG. 2) of the classifying rotor 35 by the suction force of the blower 364 and passed through the fine powder discharge port 45 and the cyclone inlet 359 of the fine powder discharge pipe. 369 and bug 362. The finely pulverized product from which fine powder and ultrafine powder have been removed reaches the surface modification zone 49 in the vicinity of the rotor 32 via the second space 48 and is provided in the hammer 33 and the main body casing 30 provided in the rotor 32. The surface of the particles is modified by the stator 34. The particles subjected to the surface modification reach the classification rotor 35 again while turning along the guide ring 36, and fine particles and ultrafine particles are removed from the surface-modified particles by the classification rotor 35 classification. . After performing the treatment for a predetermined time, the discharge valve 41 is opened, and the surface-modified toner particles from which fine powder having a predetermined particle diameter or less and ultrafine powder are removed are taken out from the surface reforming apparatus.

The surface reforming apparatus used in the present invention has a rotor 32, a finely pulverized material (raw material) charging part 39, a classification rotor 35, and a fine powder discharging part from the lower side in the vertical direction. Therefore, normally, the drive portion (motor or the like) of the classification rotor 35 is provided further above the classification rotor 35, and the drive portion of the rotor 32 is provided further below the rotor 32. The surface reforming apparatus used in the present invention is a finely pulverized product (raw material) classified into a classification rotor, such as a TSP classifier (manufactured by Hosokawa Micron Corporation) having only a classification rotor 35 described in JP-A-2001-259451. It is difficult to supply from the vertically upward direction of 35.
It is preferable in terms of toner productivity that the fine powder generated by the surface modification device is collected by a collecting device such as a cyclone or a bag and returned to the toner raw material mixing step and reused.

The toner particle manufacturing method and toner particle manufacturing apparatus according to the present invention are characterized in that the surface modification means is arranged with a rotor and a fixed distance in the horizontal direction from the outer edge of the rotor to the rotor. The rotor has a plurality of hammers on its outer edge, and one or more grooves are provided on the surface of the stator facing the rotor. In the groove, the circumferential inclination of the groove forms an angle of 60 degrees or more and 90 degrees or less with respect to the rotation axis of the rotor with respect to the rotation axis of the rotor.

  That is, as a result of examination by the present inventors, the surface of the stator has grooves as shown in FIG. Further, the circumferential inclination of the groove is such that θ1 is 60 degrees or more and 90 degrees or less, where θ1 is the angle of the groove toward the rotation direction of the rotor with respect to the rotation axis of the rotor. The surface modification of the toner particles can be performed efficiently. When the groove angle θ1 is 90 degrees, it is a circumferential groove, and when the angle θ1 is 60 degrees or more and less than 90 degrees, it may be a circumferential groove or a helical groove. When the groove is on the circumference, there are a plurality of grooves, and the interval between the grooves is not particularly limited. In the case of a spiral shape, the number of grooves may be one, or a plurality of spiral grooves. In the case of a plurality of spiral grooves, the interval between the grooves is not particularly limited.

When the circumferential or spiral angle θ1 is 60 degrees or more and 90 degrees or less, a swirl flow is generated in the groove, so that classification accuracy is improved, and toner particles having a sharp particle size distribution can be obtained efficiently. .
On the other hand, if the groove angle θ1 is less than 60 degrees, a swirl flow hardly occurs along the groove, and the classification accuracy tends to deteriorate. In addition, when the swirl flow is difficult to occur and the swirl flow is weak, the toner particles dispersed by the rotor are strongly struck against the stator, and the impact of the impact may cause the wax component to ooze out on the toner particle surface. Conceivable. As a result, the wax component present on the toner surface tends to contaminate the magnetic carrier, sleeve, etc. during long-term use. On the other hand, when the angle exceeds 90 degrees, the spiral in the rotating direction of the rotor is directed to the lower side of the surface reforming apparatus, and no swirling flow is generated.
The circumferential or helical angle θ1 is more preferably 75 degrees or more and 90 degrees or less from the viewpoint of reducing the amount of ultrafine powder.

  The shape of the circumferential or spiral groove is not particularly limited as long as a swirl flow is generated, such as a square (trapezoid), a triangle, and a U-shape, but is preferably a square (trapezoid). And as for the dimension of the groove | channel shape shown in FIG. 6, it is preferable that groove width W1 is 1 mm or more and 10 mm or less, and groove depth D1 is 1 mm or more and 10 mm or less. Moreover, it is preferable that the digging angle of the groove side surface with respect to the stator surface is 45 degrees or more and 90 degrees or less at the upper end and the lower end of the groove. Further, the peak width P1 of the convex portion formed between adjacent grooves of the stator is preferably 2 mm or more and 20 mm or less. Further, the number of grooves in the stator is preferably 1 or more and 50 or less in the case of a circumferential groove, and in the case of a spiral groove, the number of grooves in the stator is 1 to 50 rotations. It is preferable.

Further, as shown in FIG. 1, the length A (mm) of the hammer in the direction of the rotation axis of the rotor and the length B (mm) of the stator in the direction of the rotation axis are 2. It is preferable to satisfy 0 ≦ B / A ≦ 15.0. When B / A is smaller than 2.0, the stator length B with respect to the hammer length A is short, and a sufficient groove cannot be secured in the stator. The accuracy tends to deteriorate. For this reason, the amount of fine powder increases, and there is a tendency for fogging during long-term durability to occur. On the other hand, when B / A is larger than 15.0, the yield tends to be deteriorated because the discharge performance is deteriorated. Further, the length A (mm) of the hammer in the direction of the rotation axis of the rotor is preferably 10 mm or more and 100 mm or less, and the length B (mm) of the stator in the direction of the axis of rotation is 20 mm or more and 400 mm or less. Good.
It is more preferable that B / A satisfies 4.7 ≦ B / A ≦ 9.3 from the viewpoint of balancing the classification accuracy and the discharge performance in a balanced manner.

  Further, the surface modification apparatus of the present invention has guide means for partitioning the space between the classification means and the surface modification means into the first space and the second space, and a guide ring is used as the guide means. Can do. Due to the presence of the guiding means, when the particles whose surface is modified by the swirling flow move above the surface modifying apparatus, the particles can be guided to the classification means. The guide means used in the present invention is not particularly limited as long as it can partition the space.

  From the above, it is considered that the surface shape state of the surface modified particles depends on the motion state of the surface modified particles in the surface modifying apparatus. That is, in order to obtain surface modified particles having a higher degree of circularity with higher yield, it is important to control the motion state of the surface modified particles in the surface modifying apparatus. In the present invention, the surface modification device used in the surface modification step is a surface modification device as shown in FIG. 1, and the shape of the stator is as shown in FIGS. 5 and 6 described above. Thereby, the dispersion state after the surface modification zone in the surface modification apparatus becomes better. Furthermore, surface-modified particles having a sharp particle size distribution from which fine powder having a predetermined particle size or less are removed and having a high degree of circularity can be obtained with higher yield. Furthermore, since the toner particles dispersed by the rotor are appropriately hit against the stator, exposure of the wax component to the toner particle surface can be suppressed.

The surface of the hammer and / or stator used in the present invention is preferably coated with a chromium alloy plating containing at least chromium carbide. As the hammer and / or the base material of the stator used in the present invention, carbon steel such as S45C or chromium molybdenum steel such as SCM material can be used. By coating the surface of these base materials with a chromium alloy, the surface hardness is large, the wear resistance is high, and a long-life hammer or stator is preferable. Furthermore, chromium carbide (Cr ₂₃ C ₆ ), which has a strong intermolecular bonding force, is present in the chromium alloy from the surface of the hammer and the stator to a depth of 5 μm or more, thereby improving the adhesion between the coating and the surface of the base material. This is preferable because the frequency of occurrence of phenomena such as peeling and cracking can be minimized.

  In the present invention, the surface of the base material of the chromium alloy containing chromium carbide can be processed by “plating” to finish the surface uniformly and smoothly, reduce the friction coefficient, and improve the wear resistance. It becomes possible. An example of such a plating process is a dicron process (Chiyoda Daiichi Kogyo Co., Ltd.).

  Furthermore, in the method and apparatus for producing toner particles of the present invention, it is preferable that the finely pulverized product (raw material) supplied to the raw material charging port 37 of the surface modifying device has a specific particle size distribution. Furthermore, it is preferable that the fine powder amount of the toner particles (surface modified particles) after the surface modification treatment by the surface modification device is controlled to a predetermined amount.

In the present invention, the finely pulverized product (raw material) supplied to the surface reforming apparatus has a weight average particle diameter (D4) of 4.0 μm or more and 10.0 μm or less, and a fine powder amount having a particle diameter of 4.0 μm or less. Of 4
It is preferably 0% by number or more and 80% by number or less. The toner particles (surface modified particles) obtained after the surface modification treatment by the surface modification apparatus have a weight average particle diameter (D4) of 4.0 μm or more and 10
. It is preferable that the ratio of the fine powder amount of 0 μm or less and the particle size of 4.0 μm or less is 5% by number or more and 40% by number or less.

  The particle size distribution of the finely pulverized product contained in the toner particles affects the classification efficiency of the toner particles. When there are many fine particles in the finely pulverized product, the classification time becomes long, and even particles that do not need to be classified and removed are removed by classification, which may cause a reduction in classification yield. Furthermore, the cohesiveness of the finely pulverized product becomes high when performing classification, and there is a tendency that fine powder that should be removed from the toner particles cannot easily be removed. Toner obtained from such toner particles There is a tendency for fogging to occur.

  When the weight average particle diameter (D4) of the finely pulverized product (raw material) supplied to the surface reformer is smaller than 4.0 μm, the cohesiveness between the particles tends to be high and efficient classification tends to be difficult. . Further, when the weight average particle diameter (D4) of the finely pulverized product (raw material) is larger than 10.0 μm, the toner obtained from such toner particles tends to be difficult to form a clear image quality.

  In addition, when the proportion of particles having a particle size of 4.0 μm or less supplied to the surface modification device is less than 40% by number, the toner obtained from such toner particles has a clear image quality. Tends to be difficult to form. On the other hand, when the ratio of particles having a particle diameter of 4.0 μm or less is more than 80% by number, the super fine powder in the finely pulverized product tends to increase, which is not preferable as described above. The ratio of particles having a particle size of 4.0 μm or less in the finely pulverized product is more preferably 50% by number to 75% by number.

  When the ratio of the amount of fine particles having a particle size of the toner particles (surface modified particles) obtained after the surface modification by the surface modifying apparatus used in the present invention of 4.0 μm or less is less than 5% by number, the surface modification There is a tendency for the productivity of toner particles obtained after quality treatment to decrease. If it exceeds 40% by number, toner scattering and fogging tend to occur.

  Further, the number of particles whose equivalent circle diameter is 0.6 μm or more and 400.0 μm or less is measured by a flow particle image measuring device for toner particles obtained after the surface modification treatment by the surface modification device used in the present invention. In the particle size distribution, it is preferable to control the ratio of toner particles (ultrafine powder) having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm within a range of 0% by number to 10% by number. This is because it is recognized that the amount of ultrafine powder has a correlation with the fog in the toner image. When the proportion of toner particles having a circle equivalent diameter of 0.6 μm or more and less than 2.0 μm is greater than 10% by number after the surface modification treatment, the obtained toner tends to cause a fog phenomenon. It is not preferable. The ratio of toner particles having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm is more preferably 8.0% by number or less.

  Furthermore, the average circularity measured by the flow type particle image measuring device for toner particles obtained after the surface modification treatment by the surface modification device used in the present invention is preferably 0.935 to 0.980.

  As a result of investigations by the present inventors, by setting the average circularity to 0.935 or more, preferably 0.940 or more, more preferably 0.945 or more, transfer efficiency is improved without impairing developability. It was found that the dot reproducibility was improved. Moreover, it turned out that the effect of the fluidity | liquidity provision by an external additive becomes large.

  When the average circularity is less than 0.935, the fluidity imparting effect by the external additive is reduced, so that the toner fluidity is lowered, the toner charge amount varies, the transfer efficiency is lowered, and the dot There is a tendency that reproducibility is likely to deteriorate. On the other hand, when the average circularity exceeds 0.980, the transfer residual toner on the drum tends to slip through the cleaning blade.

  “Surface modification” in the present invention means smoothing the unevenness of the particle surface, and means that the appearance shape of the particle is close to a sphere. As an indicator of the degree of surface modification of the surface modified particles of the present invention, the average circularity is used as an index in the present invention.

The measurement principle of the flow-type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) is to capture flowing particles as a still image and perform image analysis. The sample added to the sample chamber is fed into the flat sheath flow cell by a sample suction syringe. The sample fed into the flat sheath flow is sandwiched between sheath liquids to form a flat flow. The sample passing through the flat sheath flow cell is irradiated with strobe light at 1/60 second intervals, and the flowing particles can be photographed as a still image. Further, since the flow is flat, the image is taken in a focused state. The particle image is captured by a CCD camera, and the captured image is subjected to image processing at an image processing resolution of 512 × 512 (0.37 × 0.37 μm per pixel), and the contour of each particle image is extracted, The projected area S, the peripheral length L, and the like are measured.
Next, the equivalent circle diameter and the circularity are obtained using the area S and the peripheral length L. The equivalent circle diameter is the diameter of a circle having the same area as the projected area of the particle image, and the circularity C is a value obtained by dividing the circumference of the circle obtained from the equivalent circle diameter by the circumference of the projected particle image. And is calculated by the following formula.
Circularity C = 2 × (π × S) ^1/2 / L
When the particle image is circular, the degree of circularity is 1, and the degree of unevenness on the outer periphery of the particle image increases, and the degree of circularity decreases. After calculating the circularity of each particle, the range of the circularity of 0.200 or more and 1.000 or less is divided into 800, the arithmetic average value of the obtained circularity is calculated, and the value is defined as the average circularity.

  In the present invention, the transmittance (%) of the toner particles, which are the surface modified particles obtained by the surface modifying apparatus used in the present invention, in a 45 volume% methanol aqueous solution is 25% or more and less than 75%. It is preferable to be in the range.

Since the toner particles obtained by the production method of the present invention contain wax in the toner particles, at least the wax is present on the surface of the toner particles. When the toner particle surface has a small amount of wax, that is, when the transmittance (%) of the toner particles in a 45 volume% methanol aqueous solution is less than 25%, the releasing effect at the time of fixing is less likely to occur and low temperature fixing is desired from the viewpoint of energy saving. Sexual effects tend to decrease. Further, when a lot of wax is present on the toner surface, that is, when the transmittance (%) of the toner particles in a 45 volume% methanol aqueous solution is 75% or more, the wax is contaminated on the surface of the magnetic carrier or sleeve, and the toner is used during long-term use. Therefore, there is a tendency that stable chargeability cannot be obtained. Thus, when the wax is contained in the toner particles, it is important to control the amount of wax on the surface of the toner particles.
The amount of wax on the toner particle surface can be measured easily and with high accuracy by measuring the transmittance (%) in an aqueous solution of 45% by volume of methanol.

  In the method for producing toner particles of the present invention, the surface modification time in the surface modification apparatus is preferably 5 seconds or more and 180 seconds or less, more preferably 15 seconds or more and 150 seconds or less, and further preferably 15 seconds or more and 120 seconds. Less than a second. When the surface modification time is less than 5 seconds, since the surface modification time is too short, surface modified particles having desired circularity and average surface roughness tend not to be obtained, which is not preferable in terms of toner quality. In addition, when the surface modification time exceeds 180 seconds, the surface modification time is too long, which tends to cause surface deterioration due to heat generated during surface modification, occurrence of in-machine fusion, and reduction in processing capacity. Therefore, it is not satisfactory from the viewpoint of toner productivity.

  Furthermore, in the method for producing toner particles of the present invention, the cold air temperature T1 introduced into the surface modifying apparatus is preferably 5 ° C. or less, more preferably 0 ° C. or less, and further preferably −5 ° C. or less. . By setting the cold air temperature T1 introduced into the surface reforming apparatus to 5 ° C. or less, it is possible to prevent the surface deterioration of the toner particles due to the heat generated during the surface modification and the in-machine fusion. When the cold air temperature T1 introduced into the surface reforming apparatus exceeds 5 ° C., the surface of the toner particles is liable to be deteriorated by the heat generated during the surface reforming, and the in-machine fusion tends to occur. It is not satisfactory enough.

  The cool air introduced into the surface reforming apparatus is preferably dehumidified from the viewpoint of preventing condensation in the apparatus from the viewpoint of toner productivity. A well-known thing can be used as a dehumidifier. The supply air dew point temperature is preferably −15 ° C. or lower, and more preferably −20 ° C. or lower.

  Further, in the method for producing toner particles of the present invention, the inside of the surface modifying apparatus is provided with a jacket for cooling inside the apparatus, and a refrigerant (preferably cooling water, more preferably an antifreeze such as ethylene glycol) is provided in the jacket. The surface-modified particles are preferably subjected to a surface modification treatment while passing through. By cooling the inside of the machine with the jacket, it is possible to prevent the toner particles from undergoing surface modification and fusion within the machine due to heat during surface modification.

  In addition, it is preferable that the temperature of the refrigerant | coolant passed in the jacket of a surface modification apparatus shall be 5 degrees C or less, More preferably, it is 0 degrees C or less, More preferably, it is -5 degrees C or less. By setting the temperature of the refrigerant passed through the jacket in the surface reforming apparatus to 5 ° C. or less, it is possible to prevent toner particle surface deterioration and in-machine fusion due to heat generated during surface modification. If the temperature of the refrigerant introduced into the cooling jacket exceeds 5 ° C, the toner particles are prone to surface modification and in-machine fusion due to heat generated during surface modification. It is not possible.

  Furthermore, in the method for producing toner particles of the present invention, the temperature T2 in the fine powder outlet located behind the classification rotor in the surface reforming apparatus is preferably 60 ° C. or less, more preferably 55 ° C. or less, still more preferably Is 50 ° C. or lower. By setting the temperature T2 in the fine powder discharge port at the rear of the classification rotor in the surface reforming apparatus to 60 ° C. or less, it is possible to prevent surface deterioration of the toner particles due to heat generated during surface reforming and in-machine fusion. it can. If the temperature T2 in the fine powder outlet located behind the classifying rotor in the surface reformer exceeds 60 ° C, it is presumed that a higher temperature is affecting the surface reforming zone in the surface reformer. The For this reason, the toner particles are liable to be surface-modified due to heat generated during the surface modification and to be fused in the machine, so that the toner productivity is not satisfactory.

  Furthermore, in the method for producing toner particles of the present invention, the temperature difference ΔT (T2) between the temperature T2 in the fine powder discharge port located behind the classification rotor in the surface reformer and the cold air temperature T1 introduced into the surface reformer. -T1) is preferably 100 ° C or lower, more preferably 90 ° C or lower, and further preferably 80 ° C or lower. By setting the temperature difference ΔT (T2−T1) between the temperature T2 in the fine powder outlet located behind the classification rotor in the surface reformer and the cold air temperature T1 introduced into the surface reformer to 100 ° C. or less, It is possible to prevent the toner particles from being deteriorated by the heat generated during the surface modification, and in-machine fusion. When the temperature difference ΔT (T2−T1) between the temperature T2 in the fine powder outlet located behind the classification rotor in the surface reformer and the cold air temperature T1 introduced into the surface reformer exceeds 100 ° C., the surface is improved. In the surface modification zone in the quality device, it is presumed that the temperature above it has an influence, and it tends to cause surface modification of the toner particles due to heat generated during surface modification and in-machine fusion. This is not satisfactory from the viewpoint of toner productivity.

  Furthermore, in the method for producing toner particles of the present invention, the minimum distance between the hammer installed on the outer edge of the rotor in the surface modifying apparatus and the surface of the stator facing the rotor is 0.5 mm or more. It is preferably 15.0 mm or less, and more preferably 1.5 mm or more and 10.0 mm or less.

As a result of the study by the present inventor, if the minimum distance between the rotor and the stator in the surface reforming apparatus is less than 0.5 mm, the load on the apparatus itself is increased and at the same time, the surface reforming is excessively pulverized. However, the toner particles are liable to cause surface deterioration and in-machine fusion due to heat, which is not satisfactory from the viewpoint of toner productivity. The minimum distance between the rotor and the stator is 15
. If it exceeds 0 mm, the processing capability must be reduced to obtain surface-modified particles having a desired average circularity, which is also not sufficiently satisfactory in terms of toner productivity.

  In the method for producing toner particles of the present invention, it is preferable that the tip peripheral speed at the portion with the largest diameter of the classification rotor 35 is 30 m / sec or more and 120 m / sec or less. The tip circumferential speed of the classification rotor is more preferably 50 m / sec or more and 115 m / sec or less, and further preferably 70 m / sec or more and 110 m / sec or less. When the tip peripheral speed of the portion with the largest diameter of the classification rotor 35 is slower than 30 m / sec, the classification yield tends to be lowered, and the super fine powder tends to increase in the toner particles, which is not preferable. When the speed is higher than 120 m / sec, there is a tendency that a problem of an increase in vibration of the apparatus tends to occur.

  Furthermore, it is preferable that the tip peripheral speed at the largest diameter portion of the rotor 32 is 20 m / sec or more and 150 m / sec or less. The tip peripheral speed of the rotor 32 is more preferably 40 m / sec or more and 140 m / sec or less, and further preferably 50 m / sec or more and 130 m / sec or less. When it is slower than 20 m / sec, it is not preferable because it tends to be difficult to obtain surface-modified particles having sufficient circularity. When the speed is higher than 150 m / sec, the toner particles are likely to be fixed inside the apparatus due to the temperature rise inside the apparatus, and the classification yield of the toner particles tends to be lowered. By setting the tip peripheral speeds of the classification rotor 35 and the rotor 32 in the above range, the classification yield of the toner particles can be improved and the surface modification of the particles can be performed efficiently.

  The minimum distance between the guide ring in the surface modification device and the inner wall of the device is preferably 20.0 mm or more and 60.0 mm or less, and more preferably 25.0 mm or more and 55.0 mm or less. preferable.

  Furthermore, the minimum distance between the surface facing the guide ring of the hammer installed on the outer edge of the rotor in the surface reformer and the rotor side end of the guide ring is 2.0 mm or more and 50.0 mm or less. It is preferable to set it as 5.0 mm or more and 45.0 mm or less.

  If the minimum distance between the guide ring in the surface modification device and the inner wall of the device is less than 20.0 mm, the residence time of the toner particles in the second space outside the guide ring tends to be short. For this reason, the toner particles may flow out into the first space inside the guide ring in a state where the surface is not sufficiently modified, which is not satisfactory in terms of toner productivity. In addition, if the minimum distance between the guide ring in the surface reforming apparatus and the inner wall of the apparatus exceeds 60.0 mm, the toner particle residence time in the vicinity of the rotor tends to be long. For this reason, the toner particles may be excessively pulverized during the surface modification treatment and may cause surface deterioration due to heat or in-machine fusion, which is also not fully satisfactory from the viewpoint of toner productivity.

  In addition, when the minimum distance between the surface facing the guide ring of the hammer installed on the outer edge of the rotor in the surface modification device and the rotor side end of the guide ring is less than 2.0 mm, the device The load of itself increases. At the same time, the residence time in the first space inside the guide ring tends to be long, and the toner particles are excessively pulverized during the surface modification treatment, so that they tend to cause surface alteration and in-machine fusion due to heat. Is not satisfactory enough. Also, if the minimum distance between the surface of the hammer facing the guide ring on the outer edge of the rotor and the rotor-side end of the guide ring exceeds 50.0 mm, the toner particles will be sufficiently on the surface. There is a possibility of causing a short path of flowing out into the second space outside the guide ring without being modified, which is also not sufficiently satisfactory in terms of toner productivity.

As a result of the study by the present inventors, by controlling the surface modification conditions of the surface modification device within the above range, it is possible to prevent an increase in fine powder during the surface modification and to reduce the influence of heat during the surface modification. The surface state of the toner particles can be controlled as desired. As a result, a long-life toner having good developability, transferability, cleanability, and stable chargeability can be obtained.

  That is, according to the toner production method of the present invention, the surface state of the toner particles can be controlled to a desired one. As described above, this is because the surface reforming time from the closing of the raw material supply valve to the product discharge valve of the surface reformer, the cold air temperature T1, the cooling water temperature, the fine powder outlet temperature T2, the fine powder outlet temperature T2 and the cold air temperature. ΔT with T1, hammer shape on outer edge of rotor, minimum distance between hammer and stator, rotational peripheral speed of rotor, minimum distance between guide ring and device inner wall, installed on rotor outer edge This is because the surface state of the toner can be arbitrarily controlled by controlling the minimum distance between the surface of the hammer facing the guide ring and the rotor side end of the guide ring to an appropriate state. .

Next, the method for producing the toner of the present invention will be outlined. In order to produce toner particles in the present invention, for example, a binder resin, a colorant and a wax and, if necessary, a charge control agent and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill. A kneaded product is obtained by melting or kneading using a heat kneader such as a heating roll, kneader or extruder to disperse or dissolve the colorant and wax in the binder resin. The obtained kneaded product is cooled and solidified, and the solidified product is roughly pulverized, and then finely pulverized by an air impact pulverizer such as a jet mill or a mechanical impact pulverizer to obtain a finely pulverized product. Examples of the air-type impact pulverizer include an I-DS type pulverizer (manufactured by Nippon Pneumatic Co., Ltd.), a collision-type airflow pulverizer using jet air described in FIG. 1 of JP-A-2003-262981, A method of obtaining a finely pulverized product using a classifier described in FIG. 7 of Kaihei 2003-262981 is mentioned. Examples of the mechanical pulverizer include a turbo mill manufactured by Turbo Industry Co., Ltd., a kryptron manufactured by Kawasaki Heavy Industries, Ltd., an inomizer manufactured by Hosokawa Micron Co., Ltd., and a super rotor manufactured by Nisshin Engineering Co., Ltd. Thereafter, by performing classification of the finely pulverized product and surface treatment of the particles at the same time using the above-described surface treatment apparatus, toner particles having a desired shape and a desired particle size distribution can be obtained as the surface modified particles. The toner in the present invention is preferably a toner obtained by externally adding an external additive to toner particles.

  Next, the constituent material of the toner particles containing the binder resin, wax and colorant according to the present invention will be described. In the present invention, various known toner particle materials can be used.

  As the binder resin constituting the toner particles, a resin usually used for toner can be used. The following are listed.

Examples of the binder resin used in the present invention include polystyrene; a styrene-substituted homopolymer such as poly-p-chlorostyrene and polyvinyltoluene; a styrene-p-chlorostyrene copolymer and a styrene-vinyltoluene copolymer. Styrene-vinyl naphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinylmethyl Styrenic copolymers such as ether copolymers, styrene-vinyl ethyl ether copolymers, styrene-vinyl methyl ketone copolymers, styrene-butadiene copolymers, styrene-isoprene copolymers, styrene-acrylonitrile-indene copolymers. Polymer; polyvinyl chloride, pheno Resin, natural modified phenolic resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin , Coumarone indene resin and petroleum resin. In the present invention, a crosslinked styrene resin and a crosslinked polyester resin are preferred binder resins for surface modification of the particles.

  As a comonomer for the styrene monomer of the styrenic copolymer, acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, Monocarboxylic acid having a double bond such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide or a derivative thereof; maleic acid, butyl maleate, methyl maleate, malee Dicarboxylic acids having a double bond such as dimethyl acid or derivatives thereof; vinyl esters such as vinyl chloride, vinyl acetate and vinyl benzoate; ethylene-based olefins such as ethylene, propylene and butylene; Rumechiruketon, vinyl ketones such as vinyl hexyl ketone; and the like; vinyl methyl ether, vinyl ethyl ether, vinyl ether such as vinyl isobutyl ether. These vinyl monomers are used alone or in combination of two or more.

  Examples of the crosslinking agent mainly include compounds having two or more polymerizable double bonds. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate and 1,3-butanediol dimethacrylate; divinylaniline; And divinyl ether, divinyl sulfide and divinyl sulfone divinyl compounds; and compounds having three or more vinyl groups. These can be used alone or in admixture of two or more.

  Among the physical properties of the toner, those resulting from the binder resin include a region having a molecular weight of 2,000 to 50,000 in the molecular weight distribution measured by gel permeation chromatography (GPC) soluble in tetrahydrofuran (THF). More preferably, a component having at least one peak and having a molecular weight of 1,000 to 30,000 is present in an amount of 50% to 90%.

  In the present invention, the following wax is used as the material for the toner particles from the viewpoint of improving the releasability from the fixing member during fixing and improving the fixing property. Examples of the wax include paraffin wax and derivatives thereof, microcrystalline wax and derivatives thereof, Fischer-Tropsch wax and derivatives thereof, polyolefin wax and derivatives thereof, and carnauba wax and derivatives thereof. Derivatives of these waxes include oxides, block copolymers with vinyl monomers, and graft modified products. Examples of the wax include alcohol, fatty acid, acid amide, ester, ketone, hydrogenated castor oil and derivatives thereof, plant wax, animal wax, mineral wax, and petrolactam.

  In the present invention, a charge control agent is preferably blended (internally added) into toner particles or mixed (externally added) with toner particles as a material for toner particles. The charge control agent makes it possible to control the optimum charge amount according to the development system, and in particular, it is possible to produce a toner with a more stable balance between the particle size distribution and the charge amount.

Examples of the negative charge control agent for controlling the toner to be negatively charged include organometallic complexes and chelate compounds. Examples of the organometallic complex include a monoazo metal complex, an acetylacetone metal complex, an aromatic hydroxycarboxylic acid metal complex, and an aromatic dicarboxylic acid metal complex. Further, the negative charge control agent includes aromatic hydroxycarboxylic acid, aromatic monocarboxylic acid and aromatic polycarboxylic acid and metal salts thereof; anhydrous hydroxycarboxylic acid, aromatic monocarboxylic acid and aromatic polycarboxylic acid anhydride. Products; ester compounds of aromatic hydroxycarboxylic acids, aromatic monocarboxylic acids and aromatic polycarboxylic acids, and phenol derivatives such as bisphenol.

  Examples of positive charge control agents for controlling the toner to be positively charged include nigrosine and fatty acid metal salts modified from nigrosine; tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate Quaternary ammonium salts and their lake pigments; phosphonium salts such as tributylbenzylphosphonium-1-hydroxy-4-naphthosulfonate and tetrabutylphosphonium tetrafluoroborate and lake pigments thereof; triphenylmethane dyes and lakes thereof Pigment (phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.); metal salt of higher fatty acid; dibutyls Oxide, dioctyltin oxide, such as diorganotin oxide dicyclohexyl tin oxide; dibutyl tin borate, dioctyl tin borate, include such diorgano tin borate dicyclohexyl tin borate. These charge control agents can be used alone or in combination of two or more.

  The above charge control agent is preferably used in the form of fine particles. When these charge control agents are internally added to the toner particles, they are 0.1 parts by mass or more and 20.0 parts by mass or less, particularly 0.2 parts by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass of the binder resin. Is preferably added to the toner particles.

  In the present invention, various conventionally known colorants can be used as the toner particle material. The colorant used in the present invention is adjusted to black by a chromatic colorant such as carbon black or a magnetic material, a yellow colorant, a magenta colorant, and a cyan colorant shown below as a black colorant. A combination is used.

  As the yellow colorant, compounds represented by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 168, 174, 176, 180, 181 and 191.

  As the magenta colorant, a condensed azo compound, diketopyrrolopyrrole compound, anthraquinone, quinacridone compound, basic dye lake compound, naphthol compound, benzimidazolone compound, thioindigo compound, and perylene compound are used. Specifically, C.I. I. Pigment Red 2, 3, 5, 6, 7, 23, 48; 2, 48; 3, 48; 4, 57; 1, 81; 1, 144, 146, 166, 169, 177, 184, 185, 202, 206, 220, 221, 254.

  As the cyan colorant, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds are used. Specifically, C.I. I. Pigment blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66.

  These colorants can be used alone or in combination and further in the form of a solid solution. In the present invention, the colorant is selected in consideration of hue angle, saturation, brightness, weather resistance, OHP transparency, and dispersibility in the toner. These chromatic and non-magnetic colorants are preferably contained in the toner particles in a total amount of 1.0 to 20.0 parts by mass with respect to 100 parts by mass of the binder resin.

  Furthermore, in order to improve fluidity, transferability and the like, a toner can be obtained by externally adding an external additive such as a known inorganic fine powder to the toner particles and passing through a known sieving step.

  Next, the measurement method used in the present invention will be described.

<Measurement method of weight average particle diameter (D4)>
The weight average particle diameter (D4) of the toner is calculated as follows. As a measuring device, a precise particle size distribution measuring device “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) using a pore electrical resistance method equipped with a 100 μm aperture tube is used. For setting the measurement conditions and analyzing the measurement data, the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) is used. Note that the measurement is performed with 25,000 effective measurement channels.
As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

Prior to measurement and analysis, dedicated software was set up as follows.
On the “Change Standard Measurement Method (SOM)” screen of the dedicated software, set the total count in the control mode to 50,000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman The value obtained using Coulter Co.) is set. By pressing the “Threshold / Noise Level Measurement Button”, the threshold and noise level are automatically set. In addition, the current is set to 1,600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the “aperture tube flush after measurement” is checked.
In the “Pulse to particle size conversion setting” screen of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.

The specific measurement method is as follows.
(1) About 200 ml of the electrolytic aqueous solution is put in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rotations / second. Then, the dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the dedicated software.
(2) About 30 ml of the electrolytic aqueous solution is put into a glass 100 ml flat bottom beaker. In this, "Contaminone N" (nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of neutral detergent for pH7 precision measuring instrument cleaning, made by organic builder, manufactured by Wako Pure Chemical Industries, Ltd. About 0.3 ml of a diluted solution obtained by diluting 3) with ion-exchanged water is added.
(3) Two oscillators with an oscillation frequency of 50 kHz are incorporated with the phase shifted by 180 degrees, and an ultrasonic disperser “Ultrasonic Dissipation System Tetora 150” (manufactured by Nikki Bios Co., Ltd.) having an electrical output of 120 W is prepared. About 3.3 l of ion-exchanged water is placed in the water tank of the ultrasonic disperser, and about 2 ml of Contaminone N is added to the water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.
(5) In a state where the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.
(6) To the round bottom beaker of (1) installed in the sample stand, the electrolyte solution of (5) in which the toner is dispersed is dropped using a pipette, and the measurement concentration is adjusted to about 5%. . Measurement is performed until the number of measured particles reaches 50,000.
(7) The measurement data is analyzed with the dedicated software attached to the apparatus, and the weight average particle diameter (D4) is calculated. The “average diameter” on the “analysis / volume statistics (arithmetic average)” screen when the graph / volume% is set in the dedicated software is the weight average particle diameter (D4).

<Calculation method of the amount of fine powder of 4.0 μm or less>
The number-based fine powder amount (number%) in the toner is calculated by analyzing the data after measuring the Multisizer 3 described above.
For example, the number% of particles of 4.0 μm or less in the toner is calculated by the following procedure. First, the graph / number% is set with the dedicated software, and the measurement result chart is displayed in number%. Then, check “<” in the particle size setting portion on the “format / particle size / particle size statistics” screen, and enter “4” in the particle size input section below. The numerical value of the “<4 μm” display portion when the “analysis / number statistics (arithmetic mean)” screen is displayed is the number% of particles of 4.0 μm or less in the toner.

<Measuring method of average circularity>
The average circularity of the toner particles is measured by a flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) under the measurement and analysis conditions during the calibration operation.
A specific measurement method is as follows. First, about 20 ml of ion-exchanged water from which impure solids are removed in advance is put in a glass container. In this, "Contaminone N" (nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of neutral detergent for pH7 precision measuring instrument cleaning, made by organic builder, manufactured by Wako Pure Chemical Industries, Ltd. About 0.2 ml of a diluted solution obtained by diluting the solution with ion exchange water about 3 times by mass. Further, about 0.02 g of a measurement sample is added, and dispersion treatment is performed for 2 minutes using an ultrasonic disperser to obtain a dispersion for measurement. In that case, it cools suitably so that the temperature of a dispersion liquid may become 10 to 40 degreeC. As the ultrasonic disperser, a desktop type ultrasonic cleaner disperser (for example, “VS-150” (manufactured by VervoCrea)) having an oscillation frequency of 50 kHz and an electric output of 150 W is used. Ion exchange water is added, and about 2 ml of the above-mentioned Contaminone N is added to this water tank.

The flow type particle image analyzer equipped with a standard objective lens (10 ×) was used for the measurement, and a particle sheath “PSE-900A” (manufactured by Sysmex Corporation) was used as the sheath liquid. The dispersion liquid prepared according to the above procedure is introduced into the flow type particle image analyzer, and 3000 toner particles are measured in the HPF measurement mode and in the total count mode. Then, the binarization threshold at the time of particle analysis is set to 85%, the analysis particle diameter is limited to the equivalent circle diameter of 1.985 μm or more and less than 39.69 μm, and the average circularity of the toner particles is obtained.
In the measurement, before starting the measurement, standard latex particles (for example, Duke Science)
Automatic focusing is performed using “RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5200A” manufactured by tific. Thereafter, it is preferable to perform focus adjustment every two hours from the start of measurement.

  In the examples of the present application, a flow-type particle image analyzer that has been issued a calibration certificate issued by Sysmex Corporation, which has been calibrated by Sysmex Corporation, was used. Measurement was performed under the measurement and analysis conditions when the calibration certificate was received, except that the analysis particle size was limited to a circle equivalent diameter of 1.985 μm or more and less than 39.69 μm.

<Measurement of toner transmittance in 45% by volume methanol aqueous solution>
An aqueous solution with a volume mixing ratio of methanol and water of 45:55 is prepared. 10 ml of this aqueous solution is placed in a 30 ml sample bottle (for example, “SV-30”, manufactured by Nidec Rika Glass Co., Ltd.), and 20 mg of toner is immersed on the liquid surface to cover the bottle.
The sample bottle is fixed to a fixing holder (the sample bottle lid is fixed on the extension of the center of the column) attached to the tip of the column. Then, it shakes for 5 seconds at 2.5 times / second with "Yaoi-type shaker Model-YS-LD" (made by Yayoi Co., Ltd.). At this time, the angle of shaking is such that the shaking column moves 15 degrees forward and 20 degrees backward, assuming that the vertical (vertical) of the shaker is 0 degree. In addition, it counts as what was shaken once at the time of 1 reciprocating forward and back.
Remove the sample bottle from the fixing holder and let it stand. After 30 seconds, open the lid of the sample bottle, collect the dispersion using a pipette, and place it in a 1 cm square quartz cell. At this time, care should be taken not to suck the precipitated toner or the toner floating on the liquid surface with a pipette, and only the toner dispersed in the liquid should be sucked with a pipette.
The quartz cell containing the dispersion liquid is set in a spectrophotometer “MPS2000” (manufactured by Shimadzu Corporation), and the state is kept as it is for 10 minutes to wait for the fluctuation of transmittance to settle. After 10 minutes, the transmittance (%) at a measurement wavelength of 600 nm is measured.
Transmittance (%) = (A / B) × 100
However, A is a transmitted light beam and B is an incident light beam.

  Hereinafter, the present invention will be described more specifically with specific toner production methods, examples, and comparative examples, but the present invention is not limited to these examples.

<Production Example 1 of Toner Particles>
Unsaturated polyester resin [polyoxypropylene (2,2) -2,2bis (4-hydroxyphenyl) propane / polyoxyethylene (2,2) -2,2bis (4-hydroxyphenyl) propane / terephthalic acid / Unsaturated polyester resin consisting of trimellitic anhydride / fumaric acid, Mw: 15,000, Mw / Mn: 4.5, Tg: 58 ° C.]:
100 parts by mass copper phthalocyanine pigment (CI Pigment Blue 15: 3): 5 parts by mass paraffin wax (maximum endothermic peak 73 ° C.): 4 parts by mass charge control agent (salicylic acid metal complex E-88 (manufactured by Orient)): 1 part by mass After thoroughly mixing the above materials with a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.), a twin-screw kneader (PCM-30 type, Ikegai Iron Works Co., Ltd.) set at a temperature of 120 ° C. Kneaded). The obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized material.
The resulting coarsely pulverized product is finely pulverized using a jet mill (IDS-5 type pulverizer, manufactured by Nippon Pneumatic Co., Ltd.) under a feed rate of 3 kg / hr and an air pressure of 0.6 MPa. As a result, a finely pulverized product was obtained. The finely pulverized product has a weight average diameter D4 of 5.0 μm, a ratio of particles having a particle diameter of 4.00 μm or less is 75% by number, and an average circularity of 0.9.
28.

The obtained finely pulverized product was put into the surface modifying apparatus shown in FIGS. 1 and 7, and the finely pulverized product was classified and surface-modified at the same time. At this time, in this embodiment, the outer diameter D of the rotor 32 shown in FIG. 3A is set to 400 mm, and eight hammers 33 are installed on the upper portion of the rotor 32. Further, the length A of the hammer 33 in the rotation axis direction of the rotor 32 was set to 30 mm. The rotational peripheral speed of the rotor 32 rotating counterclockwise when viewed from above was 120 m / sec. The inner diameter d of the cylindrical guide ring 36 shown in FIGS. 4A and 4B was 350 mm, and the distance between the lower part of the guide ring 36 and the upper part of the hammer 33 at the upper end of the rotor 32 was 5 mm. 2A and 2B, the blade diameter D of the classification rotor 35 is 240 mm, the blade length L of the classification rotor 35 is 130 mm, and the rotation speed of the classification rotor 35 rotating counterclockwise as viewed from above Was 80 m / sec. The length B of the stator 34 was 140 mm. The circumferential inclination of the groove of the stator 34 was 75 degrees with respect to the axis of the rotor 32 toward the rotor rotation direction. The time for one cycle of classification and surface treatment of finely pulverized product is 60 sec (input time: 12 sec,
Treatment time: 28 sec, discharge time 20 sec), and the feed amount of the finely pulverized product was 60 kg / hr. The suction air volume of the blower 364 was 20 m ³ / min, the cold air temperature T1 was −20 ° C., and the temperature of the cold water passed through the cooling jacket was −10 ° C.
As a result of operating for 30 minutes in this state, the temperature T2 in the fine powder discharge pipe behind the classification rotor 35 was stabilized at 32 ° C., and toner particles 1 were obtained. Table 1 shows the operating conditions.

  As a result of measuring the particle size distribution and circularity of the toner particles surface-modified under the above apparatus conditions, the toner particles 1 have a weight average diameter D4 of 6.2 μm and a ratio of particles having a particle diameter of 4.0 μm or less. The number of particles having an equivalent circle diameter of 0.6 μm or more and less than 2.0 μm was 2.5 number%. The average circularity of the surface-modified toner particles was 0.956, and the classification yield was 77%. Table 2 shows the physical properties relating to the toner particles 1.

<Toner Particle Production Example 2>
The toner particles 2 were removed using the same method as in Example 1 except that the circumferential inclination of the groove of the stator 34 was 90 degrees with respect to the axis of the rotor 32 toward the rotation direction of the rotor. Created. Table 1 shows the operating conditions. Table 2 shows the physical properties relating to the toner particles 2.

<Production Example 3 of Toner Particles>
Toner particles 3 were prepared in the same manner as in Example 1 except that the length B of the stator 34 was 280 mm. Table 1 shows the operating conditions. Table 2 shows the physical properties relating to the toner particles 3.

<Toner Particle Production Example 4>
The toner particles 4 were removed using the same method as in Example 1 except that the circumferential inclination of the grooves of the stator 34 was set to 60 degrees in the rotation direction of the rotor with respect to the axis of the rotor 32. Created. Table 1 shows the operating conditions. Table 2 shows the physical properties relating to the toner particles 4.

<Toner Particle Production Example 5>
Toner particles 5 were prepared using the same method as in Example 1 except that the length B of the stator 34 was set to 70 mm. Table 1 shows the operating conditions. Table 2 shows the physical properties of the toner particles 5.

<Toner Particle Production Example 6>
Toner particles 6 are produced using the same method as in Example 1 except that the length A of the hammer 33 in the direction of the axis of rotation of the rotor 32 is 30 mm and the length B of the stator 34 is 290 mm. did. Table 1 shows the operating conditions. Table 2 shows the physical properties relating to the toner particles 6.

<Toner Particle Production Example 7>
Toner particles 7 were prepared using the same method as in Example 1 except that the length B of the stator 34 was 58 mm. Table 1 shows the operating conditions. Table 2 shows the physical properties relating to the toner particles 7.

<Production Example 8 of Toner Particles>
Toner particles 8 are produced using the same method as in Example 1 except that the length A of the hammer 33 in the direction of the axis of rotation of the rotor 32 is 30 mm and the length B of the stator 34 is 304 mm. did. Table 1 shows the operating conditions. Table 2 shows the physical properties of the toner particles 8.

<Comparative toner particle production example 1>
Toner particles 9 were prepared in the same manner as in Example 1 except that the number of hammers 33 was 0. Table 1 shows the operating conditions. Table 2 shows the physical properties relating to the toner particles 9.

<Production Example 2 for Comparative Toner Particles>
Toner particles 10 were prepared using the same method as in Example 1 except that the grooves of the stator 34 were eliminated and the surface facing the rotor was flattened. Table 1 shows the operating conditions. Table 2 shows the physical properties of the toner particles 10.

<Comparative toner particle production example 3>
The toner particles 11 were removed using the same method as in Example 1 except that the circumferential inclination of the grooves of the stator 34 was set to 55 degrees in the rotation direction of the rotor with respect to the axis of the rotor 32. Created. Table 1 shows the operating conditions. Table 2 shows the physical properties relating to the toner particles 11.

<Example of manufacturing magnetic carrier>
3.5% by mass of a silane coupling agent (3- (2-aminoethylaminopropyl) trimethoxysilane) is added to magnetite powder having a number average particle size of 0.33 μm, and 100 ° C. or higher in the container. The mixture was stirred and mixed at high speed to make the magnetite fine particles oleophilic.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 40% by mass, methanol 10% by mass, water 50% by mass) 7 parts by mass-Lipophilic magnetite 83 parts by mass The above materials, 28% ammonia water 5 parts by mass, water 10 parts by mass was placed in a flask, heated and maintained at 85 ° C. over 40 minutes with stirring and mixing, and cured by polymerization reaction for 3 hours. Then, after cooling to 35 degreeC and adding water further, the supernatant liquid was removed, and the precipitate was washed with water and air-dried. Next, this was dried under reduced pressure (5 mmHg or less) at a temperature of 60 ° C. to obtain a spherical magnetic fine particle dispersed resin core (carrier core) in which a magnetic material was dispersed.

A copolymer of methyl methacrylate and a methyl methacrylate having a perfluoroalkyl group (m = 7) (copolymerization ratio (mass) 8: 2 weight average molecular weight 40,000) is added to 250 parts of melamine with respect to 100 parts by mass of the coating resin. 10 parts by mass of particles, 6 parts by mass of carbon particles having a specific resistance of 1 × 10 ⁻² Ω · cm and a particle size of 30 nm were added and dispersed for 30 minutes with an ultrasonic disperser, and used as a coating material. A mixed solvent coating solution of methyl ethyl ketone and toluene was prepared so that the resin content of the coating material was 2.0 parts by mass with respect to 100 parts by mass of the carrier core (solution concentration: 10% by mass).
The coating solution was subjected to resin coating on the surface of the magnetic fine particle dispersed resin core by volatilizing the solvent at 90 ° C. while continuously applying shear stress. The resin-coated magnetic carrier particles were heat-treated with stirring at 110 ° C. for 2 hours, cooled, crushed, classified by a 200 mesh sieve, and a volume-based 50% particle size (D50) of 35 μm was true. A magnetic carrier having a density of 3.5 g / cm ³ was obtained.

<Example 1>
A developer was prepared using the toner of toner particle production example 1 and the above magnetic carrier, and an actual machine evaluation was performed using a full-color copying machine CLC5000 made by Canon Inc. Here, the developer for start is prepared by adding 10 parts by weight of black toner to 90 parts by weight of the magnetic carrier, and mixing in a V-type mixer in an environment of normal temperature and humidity (23 ° C., 50% RH). did. The produced developer was introduced into the developing tank of the copying machine.
The modifications of the CLC5000 modified machine are as follows. A magenta station was used for the evaluation. The laser used was a 655 nm semiconductor laser, the spot diameter was narrowed, and output was possible at 1,200 dpi. Further, the surface layer of the fixing roller of the fixing unit was changed to a PFA tube, and the oil application mechanism was removed.

The following evaluation was performed using the above developing device, and the results are shown in Table 3.
(Evaluation 1) Transfer efficiency
The potential contrast of the photoconductor was adjusted so that the amount of toner loaded on the photoconductor was 0.3 mg / cm ² . After outputting 50,000 sheets using a 5% image chart in a high temperature and high humidity environment (32.5 ° C./85% RH), a solid image is output, and the photoconductor electrophotographic photosensitive drum is formed when a solid image is formed. The transfer residual toner was removed by taping with Mylar tape, and the density difference obtained by subtracting the density of the tape with only the tape stuck on the paper was calculated from the density of the tape with the tape peeled off on the paper. And it judged as follows from the value of the density difference. The density was measured with the X-Rite color reflection densitometer described above.
(Evaluation criteria)
A: Less than 0.05 (excellent)
B: 0.05 or more and less than 0.10 (good)
C: 0.10 or more and less than 0.20 (possible)
D: 0.20 or more (not possible)

(Evaluation 2) Fog The potential on the photosensitive member was adjusted so that the reflection density of the solid monochrome image portion was 1.4 and the white background portion potential was 150 V in the opposite direction to the image portion from the development bias. .
After outputting 10,000 images using a 30% image chart under high temperature and high humidity (32.5 ° C., 85% RH), the photoconductor is stopped during solid white image formation, and the photoconductor before the transfer process The toner was peeled off using Mylar tape and pasted on paper. In addition, the mylar tape was directly pasted on paper as a reference.
Regarding the measurement, DENSOMETER TC-6DS manufactured by Tokyo Denshoku Technical Center was used to measure the reflectance (%), and the difference from the reference was set as the fog value.
<Evaluation criteria>
A: The difference in reflectance is less than 0.5%.
B: The difference in reflectance is 0.5% or more and less than 1.0%.
C: The difference in reflectance is 1.0% or more and less than 2.0%. (No problem in actual use)
D: The difference in reflectance is 2.0% or more. (bad)

(Evaluation 3) Evaluation of electrification stability The electrification stability is 20,000 sheets of durable images using a horizontal band chart with an image area of 30% under high temperature and high humidity (32.5 ° C., 85% RH). And evaluated by the difference (Δ) in the charge amount of the toner at the beginning of the durability and after the end of the durability. For the measurement of the toner charge amount, 1.0 g of the developer on the developing sleeve at the beginning and end of durability was used using the apparatus shown in FIG.
<Evaluation criteria>
A: Very good (△ is less than 3.0)
B: Good (3.0 ≦ Δ <5.0)
C: Normal (5.0 ≦ Δ <7.0)
D: Bad (△ is 7.0 or more)

<Examples 2-8, Comparative Examples 1-3>
For Examples 2 to 8, the toners of toner particle production examples 2 to 8 were used. For Comparative Examples 1 to 3, Production Examples 1 to 3 of comparative toner particles were used. Otherwise, a toner was prepared in the same manner as in Example 1 and mixed with the magnetic carrier to prepare a two-component developer.
The same evaluation as in Example 1 was performed, and the results are shown in Table 3.

Schematic cross-sectional view of an example of a surface modification device (A) Schematic horizontal projection of the classification rotor, and (B) Schematic sectional view of the classification rotor. (A) Horizontal projection view of the rotor, and (B) Schematic vertical projection view of the rotor. (A) The figure for demonstrating the diameter of a guide ring, (B) The perspective view of the support body of a guide ring and a guide ring Schematic cross section of stator (circumferential groove) Enlarged view of stator groove FIG. 7 is a partial flowchart for explaining the toner production method of the present invention. It is the schematic of the apparatus which measures a triboelectric charge amount.

Explanation of symbols

30 Main body casing 31 Cooling jacket 32 Rotor 33 Hammer 34 Stator 35 Classification rotor 36 Guide ring 37 Raw material inlet 38 Raw material supply valve 39 Raw material supply port 40 Product discharge port 41 Product discharge valve 42 Product extraction port 43 Top plate 44 Fine powder discharge Portion 45 Fine powder outlet 46 Cold air inlet 47 First space 48 Second space 49 Surface modification zone 50 Classification zone 271 Suction machine 272 Measuring vessel 273 Screen 274 Lid 275 Vacuum gauge 276 Air volume adjustment valve 277 Suction port 278 Condenser 279 Electrometer 315 Constant supply unit 319 Cold air generating means 320 Cold water generating means 321 Toner particle transport means 359 Cyclone 362 Bug 364 Blower 369 Cyclone 380 Raw material hopper

Claims (4)

In a production method having a toner particle or toner surface modification step containing at least a binder resin, a wax and a colorant,
The surface modification step is performed using a surface modification device, and the surface modification device includes a classifying means for continuously discharging and removing fine powder having a particle size of at least a predetermined particle size outside the device, and mechanical impact. Surface modifying means for modifying the surface of the toner particles using force, and guide means for partitioning a space between the classification means and the surface modifying means into a first space and a second space. And
The surface modification means has at least a rotor, and a stator disposed at a constant interval in the horizontal direction from the outer edge of the rotor.
The rotor has a plurality of hammers on its outer edge;
The surface of the stator facing the rotor is provided with one or more grooves, and the one or more grooves have a circumferential inclination of the groove, and the axis of rotation of the rotor On the other hand, the toner particle manufacturing method is characterized in that an angle of 60 degrees or more and 90 degrees or less is formed in the rotation direction of the rotor.   The length A (mm) of the hammer in the direction of the rotation axis of the rotor and the length B (mm) of the stator in the direction of the rotation axis are 2.0 ≦ B / A ≦ 15.0. The toner particle manufacturing method according to claim 1, wherein the relationship is satisfied. Classifying means for continuously discharging and removing fine powder having a predetermined particle diameter or less to the outside of the apparatus, surface modifying means for modifying the surface of toner particles or toner using a mechanical impact force, and the classifying means and the surface A toner particle manufacturing apparatus having guide means for partitioning a space between the modifying means into a first space and a second space,
The surface modification means has at least a rotor, and a stator disposed at a constant interval in the horizontal direction from the outer edge of the rotor.
The rotor has a plurality of hammers on its outer edge;
One or a plurality of grooves are provided on the surface of the stator facing the rotor,
The plurality of grooves are characterized in that the circumferential inclination of the grooves forms an angle of 60 degrees or more and 90 degrees or less toward the rotation direction of the rotor with respect to the rotation axis of the rotor. Manufacturing equipment.   The length A (mm) of the hammer in the direction of the rotation axis of the rotor and the length B (mm) of the stator in the direction of the rotation axis are 2.0 ≦ B / A ≦ 15.0. The toner particle manufacturing apparatus according to claim 3, wherein the relationship is satisfied.

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