JP2006011017A - Manufacturing method and surface reformer for toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for toner in which higher conglobation of the toner is maintained and fine powder classification efficiency is high. <P>SOLUTION: The manufacturing method for toner having a process of melt kneading a composition containing at least a binder resin, a wax and a colorant, and obtaining pulverized matter by cooling and solidifying the obtained kneading matter to obtain pulverized matter, and a process of obtaining the toner particles by subjecting the obtained pulverized matter to simultaneous treatment of surface reforming and classification, wherein the process of performing the simultaneous treatment of the surface reforming and classification is performed by using the batch-operated cylindrical surface reformer. The surface reformer has a main part casing 30, a feeding section 37, a classifying section 35, a fine powder discharging section 45, surface reforming means 32 and 33, a guiding means 36 for partitioning to a first space 47 and a second space 48, and a discharging section 40. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method and apparatus for producing toner used in an image forming apparatus such as electrophotography, electrostatic recording, and electrostatic printing.

  Generally, the toner production method includes a pulverization method and a polymerization method. The toner produced by the pulverization method has an advantage that the production cost is lower than that of the polymerization method at present, and is widely used in copiers, printers and the like at present. When the toner is manufactured by the pulverization method, a predetermined amount of a binder resin, a colorant and the like are first mixed, melt-kneaded, cooled, pulverized, classified, and then a fluidity improver is added to manufacture the toner. .

  In recent years, copying machines and the like have been demanded to improve image quality, save energy, and cope with the environment. On the other hand, the technical concept of the toner has been shifted toward the spheroidization in order to achieve further reduction in the particle size, high transfer efficiency, and reduction of waste toner. In order to achieve such a technical concept by the pulverization method, a method using a mechanical pulverization method (for example, refer to Patent Document 1), a method using hot air (for example, refer to Patent Document 2), and the like can be mentioned. However, sufficient spheroidization cannot be achieved by the mechanical impact force method. Also, when the wax is contained in the toner, the method using hot air causes the wax to start to melt on the toner surface when the wax starts to melt. Exudation occurs, it becomes difficult to control the surface properties of the toner particles, and adverse effects such as image fogging occur and problems remain from the viewpoint of quality stability. On the other hand, an apparatus capable of high-performance surface treatment and fine powder removal has been proposed (see Patent Document 3). However, as a problem of the present apparatus, particularly when the degree of spheroidization is kept, fine powder removal efficiency tends to decrease so-called classification yield. Further, due to the demand for further spheroidization, the spheroidizing member of the apparatus is used at high speed rotation. In such a case, the temperature inside the apparatus (hereinafter referred to as exhaust temperature) is the toner quality. From the viewpoint of stable productivity and quality stability, it is desired to improve the temperature range that affects the temperature range.

Japanese Patent Laid-Open No. 9-85741 JP 2000-29241 A JP 2002-233787 A

  An object of the present invention is to provide a method and an apparatus for producing a toner that maintains a high sphericity of toner particles and has a high classification yield.

  The objective of this invention is providing the manufacturing method and apparatus which can reduce the exhaust temperature of a surface modification apparatus.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus for efficiently producing a toner that hardly causes image fogging.

  As a result of intensive studies, the inventors have used a surface modification device that simultaneously performs classification and surface modification treatment, and by adding finely pulverized products from a specific direction, the dispersibility of the toner in the tank is improved. As a result, it has been found that a toner capable of forming a good image while improving the classification yield can be manufactured, and the present invention has been completed.

That is, a step of melt-kneading a composition containing at least a binder resin, a wax and a colorant, cooling and solidifying the obtained kneaded product, and finely pulverizing the cooled solidified product to obtain a finely pulverized product and the obtained fine In a method for producing a toner, the method includes a step of obtaining toner particles obtained by subjecting a pulverized product to surface modification and classification at the same time.
The step of simultaneously performing the surface modification and classification is performed using a cylindrical batch type surface modification apparatus,
The surface reforming apparatus includes a cylindrical main body casing, a charging unit for charging the finely pulverized material into the main body casing, and continuously supplying fine powder having a predetermined particle size or less from the finely pulverized material charged into the main body casing to the outside of the device. Classification means for automatically discharging and removing, a fine powder discharging section for discharging fine powder removed by the classification means to the outside of the main body casing, and for treating the treated particles from which the fine powder has been removed using a mechanical impact force The surface modification means that rotates in the same direction as the rotation direction of the classification means, and the space between the classification means and the surface treatment means, the first space before being introduced into the classification means, and the fine powder by the classification means Guide means for partitioning the classified particles into a second space for introducing the particles into the surface treatment means, fine powder having a predetermined particle size or less is removed by the classification means, and surface modification treatment is performed by the surface modification means. Where It has a discharge part for discharging the physical particles as surface modified particles outside the main body casing, the finely pulverized product is introduced into the first space, and fine particles having a predetermined particle size or less are continuously discharged outside the apparatus by the classification means. While discharging and removing, it is introduced into the surface treatment means using mechanical impact force through the second space, surface modification treatment is performed, and the mixture is circulated again to the first space. By repeating the surface modification treatment using mechanical impact force, the surface modification treatment particles from which fine powder having a predetermined particle size or less has been removed are obtained.
The charging portion is formed on a side surface of the main body casing, and the inner surface of the charging pipe communicates with the charging port in a plane perpendicular to the main body casing center line of the surface reforming apparatus and passing through the center of the charging port. When the angle formed by the straight line connecting the intersection (M) with the inner surface of the casing and the center point (O) of the main body casing and the inner surface of the input pipe is X, the value of X is 60.0 degrees or more and 90.0 degrees or less. The present invention relates to a toner manufacturing method.

  Furthermore, in order to achieve the present invention suitably, the guide means has at least a cylindrical partition member, and the top of the cylindrical partition member has its tip directed in the tangential direction of the inner circumferential circle of the cylindrical partition member. When the overall height of the cylindrical partition member is L0 and the height of the dispersion louver portion is L1, L1 / L0 is 0.1 to 0.5. The toner production method according to claim 1 is preferred.

  Furthermore, in order to suitably achieve the object of the present invention, the surface modification device has a top plate that can be opened and closed at the top of the main body casing, and the upper end portion of the guide means is in close contact with the inner surface of the top plate. Preferably, the toner production method is characterized by the following.

  Furthermore, in order to suitably achieve the object of the present invention, the classification means and the surface modification means have classification rotation means and surface modification rotation means that rotate at least in the same direction, and the tip peripheral speed of the classification rotation means is 30 to 120 m / sec, the tip peripheral speed of the surface-modified rotating means is 20 to 150 m / sec, and 30 to 150 degrees or 210 with respect to the rotating direction of the rotating means with reference to the center position S1 of the charging portion. It is characterized in that the fine powder discharge part is set at a central position O1 at a position of ~ 330 degrees, the finely pulverized product is introduced into the first space, and fine particles having a predetermined particle size or less are continuously discharged out of the apparatus by the classification means. While discharging and removing, it is introduced into the surface treatment means using mechanical impact force through the second space, surface modification treatment is performed, and the mixture is circulated again to the first space. Surface modification treatment using mechanical impact force By repeating the fine powder under a predetermined grain diameter or less is removed, it is preferable that the method for producing a toner, characterized in that to obtain toner particles.

  Furthermore, in order to suitably achieve the object of the present invention, the ratio R1 / R2 of the tip peripheral speed R1 of the distributed rotating means and the tip peripheral speed R2 of the classifying rotating means is 0.4 to 2.5. Preferably, the toner production method is characterized.

Furthermore, the present invention is a batch-type surface reforming apparatus that is used in the production of toner and that simultaneously performs particle classification and spheronization treatment,
Cylindrical main body casing, input portion for supplying the finely pulverized material into the main body casing, and classifying means for continuously discharging and removing fine powder having a predetermined particle diameter or less from the finely pulverized material input into the main body casing to the outside of the apparatus. A fine powder discharger for discharging the fine powder removed by the classification means to the outside of the main body casing; and a rotation direction of the classification means for surface-treating the treated particles from which the fine powder has been removed using a mechanical impact force. Surface modification means rotating in the direction, first and second spaces provided between the classification means and the surface treatment means, the first space for introducing the particles to be treated into the classification means And a second space for introducing the particles to be treated into the surface modifying means, a guide means for partitioning the first space and the second space, and fine powder having a predetermined particle size or less by the classifying means. Removed and Has a discharge portion for discharging outside the main casing to be treated particles surface modification treatment by serial surface modification means is performed as a surface-modified particles,
The charging portion is formed on a side surface of the main body casing, and the inner surface of the charging pipe communicates with the charging port in a plane perpendicular to the main body casing center line of the surface reformer and passing through the center of the charging port. The value of X is 60.0 degrees or more and 90.0 degrees or less when the angle formed by the straight line connecting the intersection (M) with the casing inner surface and the main casing central point (O) and the inner surface of the charging pipe is X. The present invention relates to a surface modification apparatus characterized by the above.

  Furthermore, in order to suitably achieve the object of the present invention, the guide means has at least a cylindrical partition member, and an upper portion of the cylindrical partition member has a tip in a tangential direction in the inner circumferential circle direction of the cylindrical partition member. L1 / L0 is 0.1 to 0.5, where L0 is the overall length of the cylindrical partition member and L1 is the height of the dispersion louver portion. Preferably, the surface modification device is characterized.

  Furthermore, in order to suitably achieve the object of the present invention, the surface modification device has a top plate that can be opened and closed at the top of the main body casing, and the upper end portion of the guide means is in close contact with the inner surface of the top plate. Preferably, the surface modification device is characterized.

  According to the present invention, by supplying the particles to be processed from a specific direction, dispersion by a swirl flow is suitably performed, fine powder can be efficiently removed, and a high classification yield can be obtained while obtaining an image with little catching. Is possible.

  First, an overview of the surface modification apparatus used in the production method of the present invention will be given.

  The surface modification device of the present invention is a batch-type device that performs classification and surface modification treatment at the same time, and has a cylindrical main body casing, a charging unit for charging the finely pulverized material into the main body casing, and the main body casing. A classifying means that rotates in a predetermined direction for continuously removing fine powder having a predetermined particle size or less from the finely pulverized product to the outside of the apparatus to obtain treated particles, and the fine powder removed by the classifying means is removed from the main body casing. A fine powder discharge section for discharging the particles, a surface modification means for rotating the treated particles from which the fine powder has been removed using a mechanical impact force in the same direction as the rotation direction of the classification means, First and second spaces provided between the classification means and the surface treatment means, the first space for introducing the particles to be treated into the classification means and the surface treatment particles. A second space for introduction into the quality means, the first The surface-modified particles are treated with the surface-modified particles from which fine powder having a predetermined particle size or less is removed by the guiding means for partitioning the space and the second space and the surface-modifying means are removed by the classification means. And a discharge portion for discharging outside the main body casing.

  FIG. 1 is a schematic cross-sectional view showing a preferred example of a surface modifying apparatus used in the present invention. FIG. 2 is a horizontal sectional view perpendicular to the center line of the main body casing of the surface reforming apparatus according to the present invention. 3 is an external view of the guiding means in the present invention, FIG. 4 is a side view of the guiding means in the present invention, and FIG. 5 is a horizontal sectional view of the louver portion of the guiding means in the present invention. FIG. 6 is a top view of the surface modification apparatus in the present invention. FIG. 7 is a bird's-eye view of the surface modification apparatus in the present invention.

  The batch type surface reforming apparatus shown in FIG. 1 includes a cylindrical main body casing 30; a top plate 43 installed so as to be openable and closable at an upper portion of the main body casing; a fine powder discharge casing 44 which is a fine powder discharge portion; Cooling jacket 31 capable of passing water; a plurality of rectangular disks 33 on the upper surface, which are attached to the central rotating shaft in the main body casing 30 as surface modification means (even number is considered in consideration of rotational balance) A dispersion rotor 32, which is a disk-like rotating body that rotates at a high speed in a predetermined direction (usually counterclockwise as viewed from the top surface of the apparatus); The liner 34 as a fixed body having a number of grooves on the surface (there is no need to have grooves on the liner surface); the surface-modified raw material particles are classified into a predetermined particle size. , A classification rotor 35 as a classifying means that rotates in the same direction as the rotation direction of the dispersion rotor 32 for continuously removing fine powder having a predetermined particle diameter or less; fine powder removed by the classification rotor 35 is outside the apparatus (that is, the main body casing). 30), a fine powder discharge port 45 as a fine powder discharge portion formed on the side surface of the main body casing 30; a cold air inlet 46 for introducing cold air into the main body casing 30; For this purpose, the raw material inlet 37 and the raw material inlet 39 serving as input portions formed on the side surface of the main casing 30; for discharging the surface-modified powder (that is, surface-modified particles) out of the main casing 30. A product discharge port 40 and a product extraction port 42 as a discharge portion of the material; and further, between the raw material input port 37 and the raw material supply port 39 so that the surface modification time can be freely adjusted. Having a product discharge valve 41 installed between the open material feed valve 38 is location and product discharge port 40 and the product extracting hole 42,.

  The surface modification apparatus further includes a guide ring 36 as a cylindrical guide means having an axis perpendicular to the top plate 43 in the main body casing 30. The upper end of the guide ring 36 is usually provided at a predetermined distance from the top plate (usually about 20 to 50 mm), and at least a part of the classification rotor 36 is installed in a state where it is covered with the cylinder. . Further, the lower end of the guide ring 36 is provided at a predetermined distance from the disk portion of the dispersion rotor 32 or the square disk 33. By this guide ring 36, the space between the classification rotor 35 and the dispersion rotor 32-liner 34 in the apparatus is divided into a first space 47 outside the cylinder and a second space 48 inside the cylinder. . Here, the first space 47 is a space for introducing the particles to be processed into the classification rotor 35, and the second space 48 is a space for introducing the particles to be processed into the dispersion rotor. Further, a gap between the plurality of rectangular disks 33 installed on the dispersion rotor 32 and the liner 34 is the surface modification zone 49, and the classification rotor 35 and the peripheral portion of the rotor are the classification zone 50.

  The finely pulverized product supplied into the apparatus from the raw material supply port 39 is outside the guide ring by the swirl flow formed by the suction air volume by the blower (not shown), the rotation of the dispersion rotor 32, and the rotation of the classification rotor 35. , While passing through the space (that is, the first space 47), the classification process is performed by reaching the classification zone 50 in the vicinity of the classification rotor 35 through the space between the upper end of the guide ring and the top plate. Here, since the direction of the swirl flow formed in the apparatus is the same as the rotation direction of the dispersion rotor 32 and the classification rotor 35, in this embodiment, it is counterclockwise as viewed from the upper surface of the apparatus.

  The fine powder to be removed by the classification means is sucked through a slit (not shown) of the classification rotor 35 and removed through the fine powder discharge port 45. The particles to be treated after the fine powder removal reaches the surface modification zone 49 in the vicinity of the dispersion rotor 32 via the second space 48, and the surface is modified by the hammer provided in the dispersion rotor 32 and the liner 34 provided in the main body casing. Quality processing is performed. The particles to be treated that have undergone surface modification reach the classification rotor 35 again while turning along the guide ring 36 described above, and the same processing is repeated. After performing the treatment for a predetermined time, the discharge valve 41 is opened, and the surface-modified particles from which fine powder having a predetermined particle diameter or less is removed can be obtained.

  As a result of intensive studies, the present inventors have found that an improvement in classification yield can be achieved by setting the charging angle of the charging port within a predetermined range. That is, as shown in FIG. 2, the intersection of the inner surface of the inlet pipe and the inner surface of the casing (in the plane perpendicular to the main body casing center line of the surface reformer and communicating with the inlet in a plane passing through the center of the inlet ( When the angle between the straight line connecting M) and the center point (O) of the main body casing and the inner surface of the charging pipe is X, the value of X is not less than 60.0 degrees and not more than 90.0 degrees.

  Here, the effects of the present invention will be described below. The conventional charging direction of the present apparatus is a case where the angle X hits perpendicularly to the swirling flow whose angle X is 0 degrees, that is, a case where the charging direction is toward the center of the main casing. In such a case, it becomes difficult for the charged powder to efficiently ride on the swirling flow formed in the first space in the tank, and good powder dispersion cannot be achieved. Therefore, since classification is performed with a classification rotor in a state where sufficient dispersion is not performed, classification accuracy is lowered and classification yield is lowered. 90 degrees is the case where X is maximum. When X is less than 60.0 degrees, the charged powder may collide with the guide ring. In this case, the flow of the powder is disturbed, and it is difficult to maintain a good powder dispersion state. It is difficult to maintain a good classification yield. A more preferable case is when X is not less than 70.0 degrees and not more than 90.0 degrees.

As a method for supplying the finely pulverized product, it is conceivable to use screw transportation or air transportation using an ejector method. The case where the ejector method is used is preferably used since the improvement of the dispersibility of the powder can be expected. Air flow rate in this case is 3.0 m ³ / min, pressure from 0.5 m ³ / min is normally used in the case of 1.0 kg / cm ² of 4.0 kg / cm ^2.

  Furthermore, in order to suitably solve the problem of the present invention, the guide means has at least a cylindrical partition member, and an upper portion of the cylindrical partition member is a tip in a tangential direction of the inner peripheral circular direction of the cylindrical partition member. When the total height of the cylindrical partition member is L0 and the height of the dispersion louver portion is L1, L1 / L0 is 0.1 to 0.5. is there.

  Here, the function and effect of the upper louver will be described below.

  The finely pulverized product introduced into the first space of the surface modifying apparatus according to the present invention is an estimate when it reaches the vicinity of the classification rotor, but is not in a finely dispersed state in which the aggregation of powders is sufficiently solved, In the lump state, it reaches the vicinity of the classification rotor, classification is performed, and the classified one is sent to the dispersion rotor and subjected to surface modification, and a certain process is repeated. That is, it is considered that the dust density density in each part of the first space and the second space in the surface modification device is in a non-uniform state. Since it is difficult to perform regular classification and surface treatment due to such a state, the temperature inside the tank is caused by heat generation caused by a decrease in classification accuracy and a temporary load increase in the dispersion treatment. We believe that an increase will occur. On the other hand, by making the upper part of the guide ring according to the present invention into a louver structure, fine dispersion of the powder is promoted when the powder passes through the louver part, and each part of the first space and the second space in the apparatus is promoted. It is considered that the dust density density of the water becomes uniform, regular classification and surface treatment are possible, and improvement in classification yield and reduction in temperature in the tank are achieved. The range in which the louver portion according to the present invention occupies the upper part of the cylindrical partition member is such that L1 / L0 is 0.1 when the overall height of the cylindrical partition member is L0 and the height of the dispersion louver portion is L1. To 0.5. If it is less than 0.1, a sufficient dispersion effect cannot be obtained, and if it is more than 0.5, powder that cannot reach the classification rotor from the first space may be generated. It is not possible to do this.

  In a more preferred aspect, the upper end portion of the guiding means is in close contact with the inner surface of the top plate. In this case, all the powder that reaches the classification rotor will reach the louver, so that fine dispersion and uniform dispersion of the powder inside the apparatus can be achieved more effectively, and the object of the present invention can be achieved more suitably. Become.

  The specification of the guide ring is that the upper louver part and the lower guide ring part can be divided so that the upper part can be configured as a louver. The structure of the upper louver part (the gap width between each louver and the number of louvers) , The louver angle, the height of the louver portion, etc.) are appropriately selected to find the optimum conditions. In general, the gap width between individual louvers is preferably set at equal intervals, and the gap width between the individual louvers is preferably set in the range of 5 mm to 40 mm, more preferably in the range of 7 mm to 25 mm. is there. When the gap width between the individual louvers is narrower than 5 mm, it may be difficult for the powder to pass smoothly between the louvers. When the gap width between the individual louvers is larger than 40 mm, a sufficient dispersion effect is obtained. It may be difficult to obtain. The number of louvers is appropriately determined in relation to the gap width between louvers.

  Furthermore, when the object of the present invention is suitably achieved, the positional relationship between the raw material supply position and the fine powder outlet is specific. When viewed from the top of the apparatus, the relationship between the center position of the supply port (see FIG. 6) and the center position of the fine powder discharge port (see FIGS. 6 and 7) is a predetermined positional relationship.

  That is, the classification means and the surface modification means have at least a classification rotation means and a surface modification rotation means that rotate in the same direction, and the tip peripheral speed of the classification rotation means is 30 to 120 m / sec. The tip peripheral speed of the means is 20 to 150 m / sec, and the center position of the fine powder discharging part is at a position of 30 to 150 degrees or 210 to 330 degrees with respect to the rotation direction of the rotating means with reference to the center position S1 of the charging part. This is the case with O1. The relationship between the raw material input part position and the fine powder discharge part position is defined as follows based on FIG. The central portion refers to the midpoint of the pipe diameter (or width) when the device is viewed from the top. Here, the angle representing the positional relationship is defined as a straight line S1-M2 and a straight line O1 based on an intersection M2 between a straight line passing through the middle point S1 parallel to the raw material charging direction and a straight line passing through the middle point O1 parallel to the fine powder discharge direction. The angle (θ) expressed from −M2. The angle is determined based on the rotation direction of the dispersion / classification rotor. FIG. 2 shows a case where the dispersion and classification rotor rotates counterclockwise around M1. 180 degrees is when the input direction and the discharge direction are the same and parallel. 0 degree is a case where the input direction and the discharge direction are opposite and parallel.

  The effect of this specific positional relationship is considered as follows.

  The basic configuration of the apparatus according to the present invention is as follows. Surface reforming means (hereinafter referred to as a dispersion rotor) from the lower side in the vertical direction, raw material charging part upward, and classification means (hereinafter referred to as classification rotor) upward. ), And further has a fine powder discharger in the upward direction. Therefore, in the case of the apparatus according to the present invention, it is usually necessary to provide the classifying rotor and the driving part (motor, etc.) of the dispersing rotor further above the classifying rotor, and further in the lower part of the classifying rotor. Therefore, for example, like a TSP classifier (manufactured by Hosokawa Micron Co., Ltd.) having only a classification rotor, it is thought that it contributes to high classification yield, but supplying the raw material from the vertical upward direction of the classification rotor is It becomes very difficult. Basically, in the case of the apparatus according to the present invention, the raw material supply direction and the fine powder discharge direction are limited, and it is necessary to provide them in parallel with the rotation surfaces of the classification rotor and the dispersion rotor. However, when the fine powder discharge direction (suction direction) is parallel to the rotation surface of the classification rotor, the distribution of the suction force and centrifugal force near the classification rotor is more uneven than when the fine powder discharge direction is perpendicular to the classification rotor rotation surface. It is easy to become. Furthermore, the feed material supplied in parallel with the rotating surface of the dispersion rotor is first dispersed and swirled by the suction air volume and the swirling flow formed by the dispersion rotor, and is supplied to the vicinity of the classification rotor. In this case, in order to maintain a high yield, it is necessary to finely disperse the agglomerated powder and smoothly supply it to the classification zone near the classification rotor without causing turbulence. Therefore, the non-uniformity of the centrifugal force and the suction force distribution formed in the vicinity of the classification rotor has a greater influence on the classification yield than a conventional apparatus having only a classification function. By changing the position of the fine powder discharge port, a change occurs in the balance distribution of the suction force and the centrifugal force near the classification rotor. Therefore, when the positional relationship between the input portion and the fine powder discharge portion is around 180 degrees, it is only an assumption, but the suction force from the classification rotor acts abruptly on the swirling flow formed by the dispersion rotor. The strong centrifugal force formed by the classification rotor cannot act effectively, so that the dispersion is insufficient and the classification yield tends to decrease. Even in the vicinity of 0 degree, since the suction force tends to be too strong, it is considered that the classification yield tends to decrease in a state of insufficient dispersion without being swirled. In the case of 30 to 150 degrees and 210 to 330 degrees, a strong classification force can be obtained because the strong centrifugal force formed by the classification rotor effectively acts on the raw material wound up by the dispersion rotor. thinking.

  Further, the tip peripheral speed of the classifying rotating means needs to be 30 to 120 m / sec. When it is less than 30 m / sec, deterioration of the classification yield and increase of ultrafine powder are seen, which is not preferable. If it is greater than 120 m / sec, problems such as an increase in apparatus vibration occur, which is not preferable. The tip peripheral speed of the surface modifying means needs to be 20 to 150 m / sec. If it is less than 20 m / sec, sufficient circularity cannot be obtained, which is not preferable. If it is higher than 150 m / sec, toner adhesion inside the apparatus due to temperature rise inside the apparatus and a reduction in classification yield are undesirable. Furthermore, we maintain a high degree of circularity and a good classification yield when the ratio R1 / R2 of the tip peripheral speed R1 of the distributed rotor to the tip peripheral speed R2 of the classification rotor is in the range of 0.4 to 2.5. I found out. When the value of R1 / R2 is smaller than 0.4, sufficient circularity cannot be obtained, and it becomes difficult to satisfy the essential quality. On the other hand, when R1 / R2 is larger than 2.5, it is presumed that the swirl flow around the classification rotor is disturbed by the relatively high swirl flow velocity formed by the dispersed rotor, but the classification yield is reduced. It is not preferable to be seen. More preferably, it is the range of 0.6-2.2.

Furthermore, in the production method of the present invention, in the particle size distribution of the finely pulverized product, the weight average particle size D4 is 3.5 to 7.5 μm, 4.0 μm or less is 80% by number or less, and the specific gravity is 1.0 g / cm ^{3 to} 1.5 g / cm ³ . The present invention is aimed at optimizing the dispersibility in the classification zone of the present apparatus, and the effect of the present invention tends to become apparent when a toner having higher cohesion is used. When D4 is smaller than 3.5 μm, the cohesiveness is too high, resulting in poor dispersion and a reduction in classification yield. In addition, the fogging phenomenon is deteriorated in view of image quality, which is not preferable. If it is larger than 7.5 μm, it becomes difficult to obtain a clear high image quality which is a major premise of toner development, which is not preferable. A more preferable range is 3.5 μm to 6.3 μm. On the other hand, if the particle size is 4.0 μm or less, the classification yield is extremely deteriorated, which is not preferable. A finely pulverized product having a specific gravity greater than 1.5, for example, a toner containing a magnetic material of about 30% by mass or more, and a non-magnetic toner having a specific gravity of 1.5 or less or a finely pulverized product containing a small amount of magnetic material. When examined with this device, it is assumed that the specific gravity greater than 1.5 is due to the higher toner specific gravity, but it tends to disperse and tends not to cause a significant reduction in classification yield. It is in. Therefore, when a specific gravity of 1.5 g / cm ³ or less is used, the effect of using the means of the present invention tends to become apparent as compared with the case of using a specific gravity greater than 1.5 g / cm ^3. .

  As an indicator of the degree of surface modification of the surface modified particles, the average circularity can be used as an index in the present invention.

  The average circularity in the present invention is used as a simple method for quantitatively expressing the shape of particles, and in the present invention, measurement is performed using a flow type particle image analyzer FPIA-1000 manufactured by Toa Medical Electronics, The circularity of the measured particles is obtained by the following formula, and the value obtained by dividing the total circularity of all the measured particles by the total number of particles is defined as the average circularity.

  As a measurement method, about 5 mg of toner is dispersed in 10 ml of water in which about 0.1 mg of a nonionic surfactant is dissolved to prepare a dispersion, and ultrasonic waves (20 kHz, 50 W) are irradiated to the dispersion for 5 minutes. The degree of circularity of the toner is measured with the above apparatus at a dispersion concentration of 5000 to 20000 / μl.

  The “average circularity” in the present invention is an index of the degree of unevenness of the surface-modified particles, and indicates 1.000 when the toner is a perfect sphere, and the average circularity becomes smaller as the toner shape becomes more complicated. Become.

  Moreover, the amount of ultrafine powder was investigated as an evaluation standard of the present invention. This is because there is a correlation with image fogging.

  The amount of ultrafine powder is judged by the number% of 3.0 μm or less from the particle size distribution measured by FPIA-1000. 15% or less is necessary to maintain a good fog level in image evaluation.

  According to the toner production method of the present invention, the average circularity of the particles obtained in the surface modification step is 0.01 to 0.00 mm higher than the average circularity of the finely pulverized product introduced into the surface modification step. 05 can be increased. This is because the surface shape of the toner can be arbitrarily controlled by arbitrarily controlling the surface modification time of the surface modifying apparatus as described above. Usually, by using this apparatus, toner having a circularity of 0.935 to 0.980 can be arbitrarily obtained. From the viewpoint of improving transfer efficiency and hollowing out, it is preferable to maintain a circularity of 0.940 or more.

  The particle size distribution of the toner can be measured by various methods. In the present invention, the following measurement apparatus was used.

  That is, a Coulter Counter TA-II type or Coulter Multisizer II (manufactured by Coulter, Inc.) was used as a measuring device. A 100 μm aperture was used as the aperture, and the volume and number distribution of the toner were measured to calculate the volume distribution and the number distribution. Then, the weight-average weight average particle diameter obtained from the volume distribution according to the present invention was obtained.

  Next, the manufacturing process of the present invention will be outlined. In order to produce the toner particles according to the present invention, for example, a binder resin, a wax, a metal salt or a metal complex, a pigment or dye as a colorant, a magnetic material, a charge control agent if necessary, other additives, etc. Are mixed thoroughly by a mixer such as a Henschel mixer and a ball mill, and then melted and kneaded using a heat kneader such as a heating roll, a kneader, and an extruder so that the resins are compatible with each other. After dispersing or dissolving the dye and magnetic substance, cooling and solidifying, coarsely pulverizing the solidified product, finely pulverizing with a pneumatic impact pulverizer such as I-mill or mechanical impact pulverizer such as turbo mill and kryptron, Toner particles having a desired particle diameter can be obtained by using a batch type surface treatment and classifying apparatus that are preferably used in the present invention.

  Next, the constituent material of toner particles containing the binder resin, wax and colorant according to the present invention will be described. In the present invention, conventionally known various toner particle materials can be used without particular limitation.

  As the binder resin constituting the toner particles, any resin usually used for toner can be used, and examples thereof include the following.

  The binder resin used in the present invention includes, for example, a homopolymer of styrene such as polystyrene, poly-p-chlorostyrene and polyvinyltoluene, and a substituted polymer thereof; styrene-p-chlorostyrene copolymer, styrene. -Vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer Polymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer Styrenic copolymers such as coalesced; Vinyl chloride, phenolic 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 can be used. Cross-linked styrene resins are also preferred binder resins.

  Examples of the comonomer for the styrene monomer of the styrene copolymer include 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 acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide or a substituted product thereof; for example, maleic acid, butyl maleate, Dicarboxylic acids having a double bond such as methyl maleate and dimethyl maleate and substituted products thereof; for example, vinyl esters such as vinyl chloride, vinyl acetate and vinyl benzoate; Ethylenic olefins such as alkylene; for example, vinyl methyl ketone, vinyl ketones such as vinyl hexyl ketone; for example, vinyl methyl ether, vinyl ethyl ether, vinyl ethers such as vinyl isobutyl ether; and the like. These vinyl monomers are used alone or in combination.

  Here, as the crosslinking agent, compounds having two or more polymerizable double bonds are mainly used. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; for example, ethylene glycol diacrylate and ethylene glycol diacrylate. Carboxylates having two double bonds, such as methacrylate and 1,3-butanediol dimethacrylate; divinyl compounds of divinylaniline, divinyl ether, divinyl sulfide and divinyl sulfone; and compounds having three or more vinyl groups; Can be used alone or as a mixture.

  As a factor attributed to the binder resin, as a preferable physical property of the toner, in the molecular weight distribution measured by GPC of THF-soluble matter, the toner has at least one peak in a molecular weight region of 2,000 to 50,000, and the molecular weight More preferably, 1000 to 30,000 components are present in an amount of 50 to 90%.

  In the present invention, the following waxes are used as the material for the toner particles from the viewpoint of improving releasability from the fixing member at the time of fixing and improving fixability. 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, carnauba wax and derivatives thereof, and the derivatives include oxides and vinyl monomers. Block copolymers and graft-modified products. In addition, alcohols, fatty acids, acid amides, esters, ketones, hydrogenated castor oil and derivatives thereof, plant waxes, animal waxes, mineral waxes, petrolactams and the like can also be used.

  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.

  As the negative charge control agent for controlling the toner to be negatively charged, for example, organometallic complexes and chelate compounds are effective, and monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acid metal complexes, and aromatic dicarboxylic acids. There are metal complexes. Others include aromatic hydroxycarboxylic acids, aromatic monocarboxylic acids and aromatic polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenols.

The positive charge control agent for controlling toner to be positively chargeable, for example, modified products by nigrosine and fatty acid metal salts; tributyl benzyl ammonium-1-hydroxy-4-Nafutosuruhon salt, tetrabutyl ammonium tetrafluoroborate Quaternary ammonium salts such as: onium salts such as phosphonium salts and their lake pigments; triphenylmethane dyes and lake pigments thereof (as rake agents include phosphotungstic acid, phosphomolybdic acid, Phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.); metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibuty Suzuboreto, dioctyl tin borate, such as diorganotin tin borate such dicyclohexyl tin borate; is.

  These charge control agents can be used alone or in combination of two or more.

  The above-described charge control agent is preferably used in the form of fine particles. In this case, the number average particle diameter of these charge control agents is particularly preferably 4 μm or less, and more preferably 3 μm or less. When these charge control agents are internally added to the toner particles, they are preferably added to the toner particles in an amount of 0.1 to 20 parts by mass, particularly 0.2 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  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 or the like 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 are preferably used.

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

  As the cyan colorant, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, and basic dye lake compounds can be used. Specifically, C.I. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66 and the like can be used particularly preferably.

  These colorants can be used alone or mixed and further used 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 colorants are contained in the toner particles in a total amount of 1 to 20 parts by mass with respect to 100 parts by mass of the binder resin.

  Further, in order to improve fluidity, transferability, etc., a toner can be obtained by externally adding a known external additive such as inorganic fine powder to the toner particles and passing through the sieving step presented in the present invention. .

  Hereinafter, the present invention will be specifically described with specific toner production methods, examples, and comparative examples.

<Example 1>
Unsaturated polyester resin 100 parts by mass Copper phthalocyanine pigment 4 parts by mass (CI Pigment Blue 15: 3)
Paraffin wax 5 parts by mass (maximum endothermic peak 73 ° C)
-Charge control agent (salicylic acid metal complex E-88 (manufactured by Orient Chemical Co., Ltd.) 2 parts by mass The above-mentioned ingredients were mixed well with a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.), then the temperature The mixture was kneaded with a biaxial kneader (PCM-30, manufactured by Ikegai Iron Works Co., Ltd.) set at 110 ° C. The obtained kneaded product was cooled and coarsely pulverized to 1 mm or less with a hammer mill for toner production. A crude product was obtained.

The obtained toner raw material coarsely pulverized product was pulverized with an I-DS5 type pulverizer (manufactured by Nippon Pneumatic) using jet air to obtain a finely pulverized product. The particle size of the finely pulverized product was D4 of 5.2 μm, 4.0 μm or less, and the number was 68%. A finely pulverized product having an inlet angle of 90 degrees as shown in FIG. 2 was used. The finely pulverized product was supplied by air transportation by an ejector method (air pressure set to 2.5 kg / cm ² , flow rate set to 1.5 m ³ / min). The positional relationship between the inlet and the fine powder outlet was set at 180 degrees. As for the guide ring, an upper portion having a louver structure (referred to as a normal type, L0 = 330 mm) was used. The distance between the top plate inner surface and the upper end of the guide ring was 35 mm. Under these conditions, the toner was processed with a simultaneous surface treatment / classification processor to obtain toner particles having a D4 (weight average particle diameter) of 5.7 μm and a number of 4.0 μm or less of 30%. As operating conditions, the inlet temperature is -15 ° C., the throughput is 75 kg / hr, the classification rotor rotational speed is 6500 rpm (the outer diameter of the classification rotor is 240 mm, the tip peripheral speed is 81 m / sec), the dispersion rotor is 4000 rpm (the outer diameter of the dispersion rotor is 400 mm). The tip peripheral speed was 83 m / sec), and the cycle time was 46 sec (input time: 8 sec, treatment time 30 sec, discharge time 8 sec), and the air flow was 21 m3 / min for 24 minutes. The outlet temperature at 24 minutes was 30 ° C., and the classification yield was 63%. The classification yield was determined from ((total amount of classified product obtained) ÷ (total amount of finely pulverized product charged)) × 100.

  To 100 parts by mass of toner particles, 1.4 parts by mass of hydrophobic silica was added and mixed to obtain a toner. To 5 parts by mass of this toner, 95 parts by mass of an acrylic-coated ferrite carrier was added as appropriate to prepare an external additive. When this developer was used and a Canon full color copier CLC1000 remodeled machine (with the oil application mechanism of the fixing unit removed) was evaluated in a normal environment (temperature 25 ° C., humidity 50%). The fogging level (◯: good level, ×: bad level, Δ: acceptable level, ○ Δ: intermediate level between ○ and Δ) was investigated at 10,000 sheets durability. The results are shown in Table 1.

<Example 2>
A toner is prepared and imaged and evaluated in the same manner as in Example 1 except that the guide ring has an upper louver configuration (L0 = 330 mm, L1 = 65 mm, gap width between louvers: 10 mm, number of louvers: 24). Was done. The results are shown in Table 1.

<Example 3>
The toner is prepared in the same manner as in Example 1 except that the guide ring is of the upper louver configuration (L0 = 365 mm, L1 = 100 mm and there is no gap between the upper end of the guide ring and the top plate (sealed type)). The image was evaluated. The results are shown in Table 1.

<Example 4>
A toner was prepared in the same manner as in Example 3 except that θ in the positional relationship between input and discharge was set to 270 degrees, and image evaluation was performed. The results are shown in Table 1.

<Example 5>
A toner was produced in the same manner as in Example 4 except that the angle X in the charging direction was set to 75 degrees, and the image was evaluated. The results are shown in Table 1.

<Example 6>
A toner was produced in the same manner as in Example 4 except that the angle X in the charging direction was set to 65 degrees, and the printing was evaluated. The results are shown in Table 1.

<Comparative Example 1>
A toner was prepared in the same manner as in Example 1 except that the angle X in the charging direction was set to 50 degrees, and the printing was evaluated. The results are shown in Table 1.

<Reference example>
A toner was prepared in the same manner as in Example 1 except that the angle X in the charging direction was set to 0 degree, and image printing was evaluated. The results are shown in Table 1.

It is a schematic sectional drawing of the surface modification apparatus used in the surface modification process of this invention. It is a horizontal cross section with respect to the main body casing centerline of the surface modification apparatus used in the surface modification process of this invention. It is an external view of the partition member which comprises the surface modification apparatus used in the surface modification process of this invention. It is a side view of the partition member which comprises the surface modification apparatus used in the surface modification process of this invention. It is an upper section of the partition member which constitutes the surface modification device used in the surface modification process of the present invention. It is a top view of the surface modification apparatus used in the surface modification process of the present invention. It is a bird's-eye view of the surface modification apparatus used in the surface modification process of the present invention.

Explanation of symbols

30: Main body casing 31: Cooling jacket 32: Dispersion rotor 33: Square disk 34: Liner 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 casing 45: Fine powder discharge port 46: Cold air inlet 47: First space 48: Second space 49: Surface modification zone 50: Classification zone 51 : Sealing material

Claims (8)

A step of melt-kneading a composition containing at least a binder resin, a wax and a colorant, cooling and solidifying the obtained kneaded product, and finely pulverizing the cooled solidified product to obtain a finely pulverized product, and the obtained finely pulverized product In a method for producing a toner, the method includes a step of obtaining toner particles obtained by simultaneously treating the surface modification and classification.
The step of simultaneously performing the surface modification and classification is performed using a cylindrical batch type surface modification apparatus,
The surface reforming apparatus includes a cylindrical main body casing, a charging unit for charging the finely pulverized material into the main body casing, and continuously supplying fine powder having a predetermined particle size or less from the finely pulverized material charged into the main body casing to the outside of the device. Classification means for automatically discharging and removing, a fine powder discharging section for discharging fine powder removed by the classification means to the outside of the main body casing, and for treating the treated particles from which the fine powder has been removed using a mechanical impact force The surface modification means that rotates in the same direction as the rotation direction of the classification means, and the space between the classification means and the surface treatment means, the first space before being introduced into the classification means, and the fine powder by the classification means Guide means for partitioning the classified particles into a second space for introducing the particles into the surface treatment means, fine powder having a predetermined particle size or less is removed by the classification means, and surface modification treatment is performed by the surface modification means. Where It has a discharge part for discharging the physical particles as surface modified particles out of the main body casing, the finely pulverized product is introduced into the first space, and fine particles having a predetermined particle size or less are continuously discharged outside the apparatus by the classification means. While discharging and removing, it is introduced into the surface treatment means using mechanical impact force through the second space, surface modification treatment is performed, and the mixture is circulated again to the first space. By repeating the surface modification treatment using mechanical impact force, the surface modification treatment particles from which fine powder having a predetermined particle size or less has been removed are obtained.
The charging portion is formed on a side surface of the main body casing, and the inner surface of the charging pipe communicates with the charging port in a plane perpendicular to the main body casing center line of the surface reforming apparatus and passing through the center of the charging port. When the angle formed by the straight line connecting the intersection (M) with the inner surface of the casing and the center point (O) of the main body casing and the inner surface of the input pipe is X, the value of X is 60.0 degrees or more and 90.0 degrees or less. A method for producing a toner, comprising:   The guide means has at least a cylindrical partition member, and the upper portion of the cylindrical partition member is composed of a plurality of louvers whose tips are directed in a tangential direction of the inner circumferential circle of the cylindrical partition member, 2. The toner production according to claim 1, wherein L1 / L0 is 0.1 to 0.5, where L0 is the total length of the partition member and L1 is the height of the dispersion louver portion. Method.   The toner manufacturing method according to claim 2, wherein the surface modifying apparatus has a top plate that can be opened and closed at an upper portion of the main body casing, and an upper end portion of the guide means is in close contact with the inner surface of the top plate. .   The classifying means and the surface modifying means have at least a classifying rotating means and a surface modifying rotating means rotating in the same direction, and the tip peripheral speed of the classifying rotating means is 30 to 120 m / sec. The tip peripheral speed is 20 to 150 m / sec, and the center position O1 of the fine powder discharge portion is at a position of 30 to 150 degrees or 210 to 330 degrees with respect to the rotation direction of the rotating means with reference to the center position S1 of the charging section. The finely pulverized product is introduced into the first space, and the fine particles having a predetermined particle size or less are continuously discharged and removed from the apparatus by the classification means, through the second space, By introducing the surface treatment means using mechanical impact force and performing surface modification treatment, and circulating again to the first space, by repeating surface modification treatment using mechanical impact force for a certain period of time. , Fine below the specified particle size Is removed, method for producing a toner according to any one of claims 1 to 3, characterized in that to obtain toner particles.   5. The toner manufacturing method according to claim 4, wherein a ratio R1 / R2 of the tip peripheral speed R1 of the dispersion rotating means and the tip peripheral speed R2 of the classification rotating means is 0.4 to 2.5. A batch-type surface modification device used for toner production, in which particle classification and spheroidization are performed simultaneously,
Cylindrical main body casing, input portion for supplying the finely pulverized material into the main body casing, and classifying means for continuously discharging and removing fine powder having a predetermined particle diameter or less from the finely pulverized material input into the main body casing to the outside of the apparatus. A fine powder discharger for discharging the fine powder removed by the classification means to the outside of the main body casing; and a rotation direction of the classification means for surface-treating the treated particles from which the fine powder has been removed using a mechanical impact force. Surface modification means rotating in the direction, first and second spaces provided between the classification means and the surface treatment means, the first space for introducing the particles to be treated into the classification means And a second space for introducing the particles to be treated into the surface modifying means, a guide means for partitioning the first space and the second space, and fine powder having a predetermined particle size or less by the classifying means. Removed and Has a discharge portion for discharging outside the main casing to be treated particles surface modification treatment by serial surface modification means is performed as a surface-modified particles,
The charging portion is formed on a side surface of the main body casing, and the inner surface of the charging pipe communicates with the charging port in a plane perpendicular to the main body casing center line of the surface reformer and passing through the center of the charging port. When the angle formed by the straight line connecting the intersection (M) with the inner surface of the casing and the center point (O) of the main body casing and the inner surface of the input pipe is X, the value of X is 60.0 degrees or more and 90.0 degrees or less. A surface modification device characterized by being.   The guide means has at least a cylindrical partition member, and the upper portion of the cylindrical partition member is composed of a plurality of louvers whose tips are directed in a tangential direction of the inner circumferential circle of the cylindrical partition member, The surface modification according to claim 6, wherein L1 / L0 is 0.1 to 0.5, where L0 is the total length of the partition member and L1 is the height of the dispersion louver portion. apparatus.   8. The surface modifying apparatus according to claim 7, wherein the surface modifying apparatus has a top plate that can be opened and closed at an upper portion of the main body casing, and an upper end portion of the guide means is in close contact with the inner surface of the top plate. .

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