JP2000162819A - Production of toner particles, toner and image-forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce toner particles that give a halftone image, having stable image density and high image quality in an environment which ronges from high temperature and high humidity to low temperature and low humidity and which do not cause toner fusion to a photoreceptor. SOLUTION: A mixture containing at least a bonding resin and a colorant is melted, kneaded, cooled and pulverized with a pulverizing means. The resultant powdery staring material is introduced into a 1st classification step, using a rotary air flow classifying means with a horizontal rotor and a fine powder recovery tube which protrudes partly into the rotor and is classified into fine and coarse powders. The fine powder thus obtained is introduced into a 2nd classification step and is classified to obtain a classified product for producing toner particles. the coarse powder obtained in the 1st classification step is introduced as a body to be pulverized into an impact type air flow pulverizing means and is pulverized finely, mixed with the powdery starting material and is reintroduced into the 1st classification step.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a toner for developing an electrostatic charge image or a toner for forming a toner image in a toner jet type image forming method, and further relates to the toner and the image forming apparatus. .

[0002]

2. Description of the Related Art Conventionally, many methods have been known as electrophotography. In general, a photoconductive substance is used to form an electric latent image on a photoreceptor by various means. The latent image is developed into a visible image by developing with toner, and the toner image is transferred to a transfer material such as paper as necessary, and then the toner image is fixed on the transfer material by heat, pressure, etc. to obtain an image. is there.

As a method of visualizing an electric latent image, a cascade developing method, a magnetic brush developing method, and the like are known.
Further, a method is also used in which a magnetic toner is used and a rotating sleeve having a magnetic pole disposed at the center is used to fly between the photosensitive member and the sleeve by an electric field.

[0004] The one-component developing method is preferable because the developing device itself can be reduced in size and weight because carrier particles such as glass beads and ferrite are not required unlike the two-component developing method.

Further, a copying machine using electrophotographic technology
In printer devices, high image quality and high stability are required. Regarding image quality, in recent years, graphic images are often taken by printers / copiers, and it has been required to improve not only line images but also graphic images.

[0006] In response to such demands, toners have been reduced in particle size, and are disclosed in JP-A-1-112253, JP-A-1-191156, JP-A-2-214156, and JP-A-2-214156. 284158, JP-A-3-18
JP-A-1952, JP-A-4-162048 and JP-A-8-278659 propose small toner particles having a specific particle size distribution.

However, in the case of toner having a small particle diameter, it is more difficult to clean the transfer residual toner remaining on the photoreceptor after the transfer process than before, and the toner which has passed through the cleaner is fused with the toner on the photoreceptor. This causes a phenomenon, which degrades the quality of the graphic image.

A graphic image is mainly a halftone image, but the image density of the halftone image changes to a greater extent than a solid black image due to a small difference in the charge amount of the toner on the toner carrier. Tend.

Therefore, it is important to stably maintain the same toner charge amount on the toner carrier and output the same halftone image at the same image density under various climatic environments around the world. Have been.

In addition, even if there is a small change in the condition for applying charge to the toner on the toner carrier, the same amount of toner charge can be stably maintained on the toner carrier and output with the same image density. Has become an important issue.

In the image forming methods such as the electrophotographic method, the electrophotographic method and the electrostatic printing method, the performance required for the toner as a developer becomes more severe, the particle size of the toner becomes smaller, and the toner becomes smaller. As for the particle size distribution, a sharp particle not containing coarse particles has been required.

As a general method for producing a toner, a binder resin for fixing to a material to be transferred and a charge control agent for imparting electric charge to particles are used as raw materials, and in addition to these, the toner itself is transported. Various magnetic materials are used for imparting, and if necessary, for example, dry-mixing is performed by adding other additives such as a release agent and a fluidity imparting agent, and thereafter, a roll mill, an extruder, or the like is used. After melt-kneading with a general-purpose kneading device and cooling and solidifying, the kneaded material is refined by various pulverizing devices such as a jet stream type pulverizer and a mechanical collision type pulverizer, and the obtained coarsely pulverized product is introduced into various wind classifiers. By performing the classification, a classified product having a particle size required for the toner is obtained.Furthermore, if necessary, a fluidizing agent, a lubricant, etc. are externally added and dry-mixed to obtain a toner to be used for image formation. I have.

Various pulverizers are used as the pulverizing means used in the above-described conventional classification / pulverization process.
A jet air flow type pulverizer using a jet air flow as shown in FIG. 11 as proposed in JP 09287 Gazette, particularly a collision type air flow pulverizer is used. As an outline, the object to be ground supplied from the object to be ground supply tube 6 is ejected from the inner wall of the acceleration tube throat portion 2 of the acceleration tube 1 and the high-pressure gas supply nozzle 3 toward the acceleration tube outlet 10. At this time, the crushed material is sucked from the crushed material supply port 5 toward the acceleration tube outlet 10 while being entrained by the gas coexisting therewith, and is uniformly mixed with the high-pressure gas in the acceleration tube throat portion 2. The collision member 11 composed of two collision portions, that is, a projection central portion 17 facing the acceleration tube outlet 10 and a peripheral collision surface 18, collides with the projection central portion 17 in a uniform state without a bias in powder concentration. Then, it is pulverized on the outer peripheral collision surface 18. The pulverizing chamber 13 has a pulverizing chamber side wall 16 for further pulverizing the pulverized material pulverized on the outer peripheral collision surface 18 by collision.

[0014] Conventionally, various classifiers are used as an airflow classifier that is connected to the above-mentioned collision type airflow pulverizer and used for classifying the powder material finely pulverized by the pulverizer. As a typical example, there is a rotary airflow classifier having a horizontal rotary rotor that classifies by a centrifugal force using a forced vortex.

For example, a teaplex (ATP) classifier manufactured by Hosokawa Micron Corporation may be used. 3 and 5
By using a rotary airflow classifier having a horizontal rotary rotor as shown in (1), the classification accuracy of fine powder and coarse powder is improved. FIG. 3 is an overall view of the air flow classifier, and FIG. 5 is a partially enlarged view (cross-sectional view) of a horizontal rotary rotor (classification rotor) 124 and a fine powder discharge pipe 129 of the air flow classifier.

In FIG. 3, reference numeral 121 denotes a cylindrical main body casing. A classification chamber 122 is formed inside the main body casing 121, and a guide chamber 123 is provided below the classification chamber 122. The rotary air classifier shown in FIG. 3 is of an individual drive type, and generates a forced vortex using centrifugal force in the classifying chamber 122 to classify into coarse powder and fine powder.
A classifying rotor 124 is provided in the classifying chamber 122, and the powder raw material 42 and the air sent into the guide chamber 123 are swirled into the classifying chamber 122 by suction from between the classifying rotors 124. In addition, classification rotor 12
The speed control of No. 4 is performed through the frequency converter 128.

The classifying rotor 124, which is a component of the classifier, has a clearance 136 of 2 × 1 as shown in FIG.
It is arranged coaxially with the fine powder discharge pipe 129 at 0 ^{-4 to} 6 × 10 ^-4 m. In order to prevent the powder material from flowing into and fusing to the clearance and stopping the classifying rotor 124 rotating at high speed, seal air is jetted toward the classifying chamber 122. However, coarse particles have a large inertial force,
It easily flows into the clearance 136. Therefore, as described above, the stability of the halftone image density was adversely affected.

[0018]

SUMMARY OF THE INVENTION It is an object of the present invention, in particular, to provide a manufacturing method which solves the above-mentioned problems in the prior art relating to a conventional method for manufacturing a toner.

That is, it is an object of the present invention to provide a method, a toner and an image forming apparatus for producing toner particles capable of obtaining a high quality halftone image with a stable image density from a high temperature and high humidity environment to a low temperature and low humidity environment.

It is a further object of the present invention to provide a method for producing toner particles which does not cause toner fusion to a photoreceptor, a toner and an image forming apparatus.

[0021]

The above objects can be attained by the following inventions.

That is, according to the present invention, a mixture containing at least a binder resin and a colorant is melt-kneaded, the obtained kneaded product is cooled, and the cooled product is pulverized by a pulverizing means. Is introduced into a first classifying step using a rotary airflow classifying means having a horizontal rotating rotor and a fine powder collecting pipe partially penetrating into the horizontal rotating rotor to obtain fine powder and coarse powder. Then, the classified fine powder is introduced into a second classifying step to classify and obtain a classified product for producing toner particles, and the coarse powder classified in the first classifying step is pulverized. Producing a toner particle, wherein the material is introduced into a collision-type airflow pulverizing means and finely pulverized, and the finely pulverized substance is mixed with the powder raw material, re-introduced to the first classification step, and subjected to circulation processing. About the method.

The present invention also relates to a toner produced by the above-mentioned production process, wherein the toner has a weight average particle diameter (D ₄ ) of 3.5 to 6.5 μm, and the toner is produced by a suction method. The ratio remaining on 200 mesh when sieving is A weight%, and the ratio remaining on 500 mesh is B
The present invention relates to a toner characterized in that A is 0.15% by weight or less and BA is 0.02 to 0.3% by weight in terms of% by weight.

Further, the present invention provides an image forming apparatus having at least a latent image carrier and a developing device for visualizing a latent image, wherein the developing device uses a toner regulating member having at least a surface material of silicone. The present invention relates to an image forming apparatus, wherein a carrier having an average surface roughness (Ra) of 1.5 μm or less is used, and a negatively-chargeable toner having the above configuration is used as a toner.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for producing a toner of the present invention will be described more specifically with reference to the accompanying drawings.

FIG. 1 is an example of a flowchart showing the outline of the manufacturing method of the present invention. In the present invention, first,
A predetermined amount of the powder raw material is supplied to the first classification means in the first classification step, and is classified into coarse powder and fine powder by the first classification means. After the classified coarse powder is introduced into the pulverizing means and finely pulverized, the finely pulverized material is again introduced into the first classifying means together with the newly supplied powdery raw material. One fine powder is introduced into a classifier, which is a second classifying means, and classified to obtain a classified product having a desired particle size distribution as a toner product. At this time, the second
As a classification means, any classifier may be used, but in order to obtain a classified product having a fine particle size distribution, FIG.
As shown in the above, it is preferable to use a multi-segmentation classifier having at least three fractionation areas of a coarse powder area, a medium powder area and a fine powder area. According to the production method of the present invention, by controlling the classification conditions and the pulverization conditions, a toner having a small and sharp particle size distribution with a weight average particle size of 6 × 10 ⁻⁶ m or less can be efficiently produced. It can be manufactured.

FIG. 2 shows an example of an apparatus system according to the manufacturing method of the present invention having the above configuration. In this apparatus system, the powdery raw material, which is a toner,
It is introduced into the first classification means 22 via the constant-rate feeder 21 and classified into coarse powder and fine powder. The classified fine powder is sent to a second quantitative feeder 24 via a collection cyclone 23, and then to a second classification means 2 via a vibration feeder 25.
7 is introduced. On the other hand, the coarse powder classified by the first classification means 22 is sent to the pulverizer 28 and finely pulverized, and then the finely pulverized material is again introduced into the first classification means 22 together with the newly added powdery raw material. And classified.

As the first classifying means used in the present invention, there is provided a rotary air flow device having a horizontal rotating rotor for classifying by centrifugal force utilizing forced vortex, and a fine powder collecting pipe partially entering the horizontal rotor. A classifier is used. For example,
Teaplex (ATP) classifier manufactured by Hosokawa Micron Corp. and the like. In the present invention, coarse powder is classified by using a rotary airflow classifier having a horizontal rotary rotor as shown in FIG. 3 and FIG. 4 and a fine powder collecting pipe partially penetrating the horizontal rotor. Improves accuracy.
FIG. 3 is an overall view of the airflow classifier, and FIG. 4 is an enlarged view (cross-sectional view) of a horizontal rotary rotor (classification rotor) and a fine powder discharge pipe of the airflow classifier.

In FIG. 3, reference numeral 121 denotes a cylindrical main body casing. A classification chamber 122 is formed inside the main body casing 121, and a guide chamber 123 is provided below the classification chamber 122. The rotary airflow classifier shown in FIG. 4 is of an individual drive type, and generates a forced vortex using centrifugal force in the classifying chamber 122 to classify it into coarse powder and fine powder.
A classifying rotor 124 is provided in the classifying chamber 122, and the powder raw material 42 and the air fed into the guide chamber 123 are swirled into the classifying chamber 122 by suction from between the classifying rotors 124. The powder raw material 42 is supplied from the raw material input port 125, and air is taken in together with the powder raw material 42 from the input port 126 and further from the raw material input port 125. The powder raw material 42 is carried to the classification chamber 122 together with the inflowing air. It is preferable that the air flowing in the guide chamber 123 through the inlet 125 and the powder material 42 be uniformly distributed to the respective classification rotors 124 in order to accurately classify. Further, it is necessary that the flow path to reach the classification rotor 124 has a shape in which concentration is unlikely to occur. However, the position of the inlet 125 is not limited to this.

The classifying rotor 124, which is a component of the classifier, has a plurality of blades arranged at regular intervals on the same circumference as shown in FIG. The size of the classifying rotor 124 is preferably such that the diameter X1 of the classifying rotor 124 is in the range of 100 to 1,000 mm depending on the size of the classifier body. Classification rotor 1 having such a shape
The speed control of 24 is performed through a frequency converter 128. Further, the fine powder discharge pipe 129 is connected to a suction fan 131 via a fine powder collecting means 130 such as a cyclone or a dust collector. By operating the suction fan 131, the fine powder discharge pipe 129 is sucked into the classification chamber 122 from between the classification rotor 124. Force is applied to generate forced vortex.

The classifying rotor 124, which is a component of the classifier, has a clearance 136 of 2 × 1 as shown in FIG.
It is arranged coaxially with the fine powder discharge pipe 129 at 0 ^{-4 to} 6 × 10 ^-4 m. A part of the fine powder discharge pipe has penetrated into the classification rotor in order to prevent the flow of the powder raw material from the clearance. In the present invention, when the penetration length X2 of the fine powder discharge pipe into the classification rotor is in the range of 5 × 10 ⁻³ to 2 × 10 ⁻¹ m, it is possible to prevent the coarse particles from flowing into the clearance.

When the length of penetration of the fine powder discharge pipe into the classifying rotor is less than 5 × 10 ⁻³ m, the length of penetration of the fine powder discharge pipe is shorter than that of the clearance, so that the inflow of coarse particles cannot be sufficiently prevented. . If the length of the fine powder discharge pipe penetrating into the classifying rotor is 2 × 10 ⁻¹ m or more, the amount of penetrating into the classifying rotor is too long, so that a strong forced vortex cannot be generated and the powder raw material can be classified accurately. It becomes impossible to do.

In the method for producing a toner according to the present invention, the first
The airflow classifier used as the classifier has the above-described structure, and the sample to be classified is introduced into the classifier through a raw material inlet 125 provided at a lower part of the classifier. That is, a pulverized material finely pulverized by a collision type air flow fine pulverizer described below,
The air including the air used for the pulverization and the newly supplied powder material is supplied from the material input port 125 to the guide chamber 1.
23. The air containing the powder raw material flows from the guide chamber 123 to between the classification rotors 124.

The powdery raw material that has flowed into the classifying chamber 122 as described above is sufficiently dispersed in the classifying chamber 122 where the forced vortex is generated by the classifying rotor 124 rotating at a high speed. Is centrifuged into coarse powder and fine powder by the centrifugal force acting on the powder. The coarse powder in the classification chamber 122 passes through a coarse powder discharging hopper 132 connected to the lower part of the main casing, and is supplied to the rotary valve 133.
To be pulverized by a collision type air flow pulverizer described later
And further pulverized, the pulverized material is again introduced into the rotary airflow classifier, which is the above-described first classification means. The fine powder classified by the first classification means is
It is sucked into the classifying rotor and discharged to the fine powder collecting means 130 through the fine powder discharge pipe 129. At this time, since the fine powder discharge pipe 129 partially enters the class rotor, coarse particles do not flow from the clearance between the classification rotor and the fine powder discharge pipe, and the fine classification is performed. Thereafter, the classified powder is introduced into a second classifying means, and is subjected to further fine classification, thereby obtaining an excellent classified product as a desired toner product.

Next, the pulverizing means used in the present invention for further pulverizing the coarse powder classified by the first classifying means as described above and making it into the first classifying means again will be described. I do. In the present invention, as the pulverizing means, for example, a collision type air flow pulverizer of the type illustrated in FIGS. 6 to 11 is used. 6 and 11 are general views of the main part of the impinging airflow pulverizer, FIG. 7 is a sectional view taken along the line AA ′ in FIGS. 6 and 11, and FIG.
9 is a sectional view taken along the line CC ′ in FIGS. 6 and 11, and FIG. 10 is an enlarged view of the collision member 11 in the grinding chamber.

The method of pulverizing the powdery raw material by the impinging airflow pulverizer of the present invention will be described with reference to FIG. The material to be crushed supplied from the material to be crushed supply cylinder 6 includes an inner wall of an accelerating tube throat portion 2 of an accelerating tube 1 having a central axis arranged in a vertical direction,
High pressure gas supply nozzle 3 whose center is on the central axis of acceleration tube 1
To the pulverized material supply port 5 formed between the outer wall and the outer wall. On the other hand, the high-pressure gas is introduced from the high-pressure gas supply port 7, passes through the high-pressure gas chamber 8, passes through one or more high-pressure gas introduction pipes 9, and expands from the high-pressure gas supply nozzle 3 toward the acceleration pipe outlet 10. Gushing. At this time, due to the ejector effect generated in the vicinity of the accelerating tube throat portion 2, the material to be comminuted is sucked from the material supply port 5 toward the accelerating tube outlet 10 while being entrained by the gas coexisting therewith. The collision member 1 is supplied from the periphery of the acceleration tube 1 into the acceleration tube, rapidly accelerates while being uniformly mixed with the high-pressure gas in the acceleration tube throat portion 2, and is disposed opposite the acceleration tube outlet 10.
The particles are crushed by colliding with the first collision surface in a state of a uniform solid-gas mixture gas stream without unevenness in dust concentration.

In the crusher shown in FIG. 6, the collision surface of the collision member 11 has a protruding central portion 17 (first collision surface) protruding in a cone shape, and the protruding central portion 17 around the protruding central portion 17. 1
An outer peripheral collision surface 18 (second collision surface) for further crushing the primary crushed material crushed in 7 by collision. The crushing chamber 13 has a crushing chamber rear side wall 16 (second side wall) for tertiarily crushing the secondary crushed material secondary crushed on the outer peripheral collision surface 18, and a width wider than the crushing chamber rear side wall 16. Crushing chamber front side wall 15 (first side wall). That is, the cross-sectional area of the front side wall 15 of the pulverizing chamber on the inside of the pulverizing chamber is larger than the cross-sectional area of the rear side wall 16 of the pulverizing chamber on the side of the pulverizing chamber.

The impact force generated at the time of collision is given to the sufficiently dispersed individual particles (objects to be crushed), and the crushed material crushed at the colliding surface of the impact member 11 is further applied to the rear side wall 16 of the crushing chamber.
The tertiary collision is repeated between the colliding member 11 and the crushing member 11 to further increase the crushing efficiency, and the crushed material is discharged from the crushed material discharge port 14 provided behind the colliding member 11.

The diameter (width B) of the front wall 15 of the crushing chamber is larger than the diameter (width C) of the rear wall 16 of the crushing chamber, and the crushing chamber 13 gradually widens from the acceleration tube outlet 10 to the front wall 15 of the crushing chamber. As a result, the back pressure in the vicinity of the outlet of the acceleration tube is reduced, so that the collision member 11 can be brought closer to the outlet of the acceleration tube. Due to this effect, a uniform gas-solid mixture flow without deviation of the dust concentration is sufficiently accelerated by the acceleration tube 1.
The object to be crushed is the collision member 1 disposed opposite to the acceleration tube outlet 10.
1 collides with a greater impact force and is pulverized with extremely high efficiency. Further, since the speed of the direction of the center axis of the acceleration tube in the direction of the front wall 15 of the grinding chamber is moderately applied to the object to be ground ejected from the outlet 10 of the acceleration tube, the secondary grinding and the grinding are effectively performed on the outer peripheral collision surface 18. Third crushing is performed on the rear wall 16 of the chamber. Such an effect can also be obtained when the diameter (width) of the crushing chamber 13 is widened from the acceleration tube outlet 10 in a direction perpendicular to the axial direction of the acceleration tube, as shown in FIGS.

In the first embodiment of the impingement type air current pulverizer of the present invention, the width of the outermost edge of the outer peripheral collision surface 18 is A, and the maximum width of the front wall of the pulverizing chamber 13 facing the collision member 11 is B. ,
When the minimum width of the side wall 16 after the crushing chamber is C, it is preferable that the following relationship is satisfied: C <B ≦ 1.6 × C A <C <1.6 × A, and more preferably It is preferable that the following relationship is satisfied: C <B ≦ 1.2 × CA <C <1.5 × A.

In the collision-type airflow pulverizer of the first embodiment, the diameter of the accelerating tube outlet 10 is D, and the distance from the accelerating tube outlet 10 to the vertex of the projecting central portion 17 which is the first collision surface of the collision member 11 is set. Length L ₁ , projected central part 1 as first collision surface
7 is L ₂ , the outer peripheral collision surface 18 as a second collision surface
Is L ₃ , the length from the outermost edge of the outer peripheral collision surface 18 as the second collision surface to the acceleration tube outlet 10 is L ₄ , and the rear wall of the grinding chamber from the acceleration tube outlet 10 to the second side wall. preferably up to 16 length when the L _5, the following relationship | that satisfies the ≦ D / {2 × tan ( α / 2)} L 5 ≦ L 4 ≦ L 2 + L 3 | L 1 It is more preferable that the following relationship is satisfied: 0 <| L ₁ | ≦ D / {2 × tan (α / 2)} L ₅ ≦ L ₄ ≦ L ₂ + L ₃ When the apex of the protruding central portion 17 of the collision member 11 is located on the upstream side of the acceleration tube outlet 10, L ₁ is positive, and conversely, on the downstream side of the acceleration tube outlet 10, the protruding central portion 17 of the collision member 11 is provided. L ₁ is negative when the vertex is located. (These heights and lengths are heights and lengths along the major axis direction of the accelerating tube.)

If C ≧ B, the pressure loss near the outlet of the accelerating tube increases, the velocity of the high-pressure gas (solid-gas mixed flow) in the accelerating tube 1 decreases, and the ejector effect in the throat portion 2 of the accelerating tube decreases. As a result, the suction amount of the powder raw material is reduced, and the acceleration of the powder raw material is insufficient, so that the impact force on the collision surface of the collision member 11 is weakened, and the crushing efficiency is reduced.

If B> 1.6 × C, the acceleration tube outlet 10
The powder raw material ejected from the container expands excessively before colliding with the collision member 11, and the flying speed of the powder raw material is reduced near the collision surface of the collision member 11, the impact force is weakened, and the crushing efficiency is reduced.

When A ≧ C, the flow path between the impact member 11 and the rear wall 16 of the crushing chamber is closed at the outermost edge of the outer peripheral collision surface 18.

If 1.6 × A ≦ C, the outer peripheral collision surface 18
Is too large, the effective tertiary collision at the rear wall 16 of the crushing chamber is not obtained, and the crushing efficiency is reduced.

If L ₁ <−D / {2 × tan (α / 2)}, the impact member 11 is too far away from the acceleration tube outlet 10, so that the impact force is weakened and the crushing efficiency is reduced.

If L ₁ > D / {2 × tan (α / 2)}, the acceleration tube outlet 10 is closed by the projecting central portion 17.

0 <L ₁ means that the tip of the first collision surface is protruding into the accelerating tube. In this case, the pulverization efficiency is further improved.

If L ₅ > L ₄ , the secondary pulverized material secondary pulverized on the outer peripheral collision surface 18 is not effectively tertiarily collided with the rear wall 16 of the pulverizing chamber, and the pulverization efficiency is reduced.

If L ₄ > L ₂ + L ₃ , the acceleration tube outlet 10
The impact surface 18 is too far away from the crushed object, the impact force of the object to be crushed is weakened, and the crushing efficiency is reduced.

In the collision type air current pulverizer of the present invention, the projection center portion 17 which is the first collision surface which protrudes in a cone shape is provided.
And an outer peripheral collision surface 19 which is a second collision surface inclined downstream with respect to a perpendicular to the long axis of the acceleration tube 1.
Preferably satisfies the following relationship: 0 <α <90, β> 030 ≦ (α + 2β) ≦ 90, and more preferably the following relationship: 0 <α <90, β > 0 50 ≦ (α + 2β) ≦ 90.

When the outer peripheral collision surface 18 does not incline downstream with respect to the perpendicular to the major axis of the accelerator tube 1 and is perpendicular to the major axis of the accelerator tube 1 (ie, when β = 0) Since the reflected flow at the outer peripheral collision surface 18 flows toward the solid-gas mixed flow ejected from the acceleration tube outlet 10, the solid-gas mixed flow is likely to be disturbed, and the powder concentration at the outer peripheral collision surface 18 is further increased. When a powder of a thermoplastic resin or a powder containing a thermoplastic resin as a main component is used as a raw material, a fusion product and an agglomerate on the outer peripheral collision surface 18 are easily generated. When such a fused material is generated, it becomes difficult to operate the apparatus stably.

When (α + 2β) <30, the impact force of the primary pulverization at the projecting central portion 17 is weakened, and the pulverization efficiency is likely to be reduced.

If (α + 2β)> 90, the primary pulverized material primary-pulverized at the projecting central portion 17 does not effectively secondary-collide with the outer peripheral collision surface 18, and the reflected flow at the outer peripheral collision surface 18 is further downstream. This tends to flow to the side, and the impact force of the tertiary pulverization on the rear side wall 16 of the pulverization chamber is weakened, so that the pulverization efficiency is likely to be reduced.

Further, in the present invention, the same effect can be obtained even with the impingement type air current pulverizer shown in FIG.

In the toner production method of the present invention, as described above, fine powder having a small particle size and a coarse powder having a particularly sharp particle size distribution can be supplied to the second classification means by the first classification step and the pulverization step. As a result, it is possible to efficiently classify the coarse powder side in the second classification step, and any known method may be used as the second classification means used in the present invention. Specifically, for example, the second classifying means has at least a fractionation area of a coarse powder area (first fractionation area), a medium powder area (second fractionation area), and a fine powder area (third fractionation area). It is preferred to use a multi-segmented classification zone. For example,
A specific example is a multi-segmentation classifier of the type shown in FIG. 12 (cross-sectional view). More specifically, a Coanda effect having a Coanda block such as an elbow jet manufactured by Nippon Steel Mining Co., Ltd. is used. Classification means may be used.

The classification chamber having such a classification area is mainly composed of side walls 141 and 142 having a shape as shown in FIG.
Lower walls 143 and 144 and Coanda block 145
Consists of The lower walls 143 and 144 are provided with knife-edge type classification edges 146 and 147, respectively, by which the classification zone is divided into three. At the lower part of the side wall 141, there are provided raw material supply pipes 148 and 149 which open to the classification chamber, and a Coanda block 145 which is bent downward with respect to the extension direction of the bottom tangent of the supply pipe to form an elliptical arc is provided. ing. Further, the upper wall 150 of the classifying chamber has a knife-edge type inlet edge 151 directed toward the lower part of the classifying chamber, and further, at the upper part of the classifying chamber, air inlet pipes 152 and 153 opening to the classifying chamber.
Is provided. In addition, the air introduction pipes 152 and 153 have gas introduction adjusting means 154 and 15 such as dampers.
5 and static pressure gauges 156 and 157 are provided. The positions of the classification edges 146 and 147 and the inlet edge 151 differ depending on the type of the raw material to be classified and the desired particle size. In addition, the outlets 158 and 159 opening into the classification chamber are provided on the bottom of the classification chamber in correspondence with the respective separation areas.
And 160 are provided. Outlets 158, 159 and 1
The opening / closing means such as a valve means may be provided in each of the 60s.

The raw material supply pipe is preferably composed of a cylindrical raw material supply pipe 148 and a pyramid-shaped cylindrical raw material supply pipe 149. The inner diameter of the raw material supply pipe 148 and the narrowest part of the raw material supply pipe 149. When the ratio of the inner diameters is set to 20: 1 to 1: 1, preferably 10: 1 to 2: 1, a good insertion speed can be obtained. As a means for introducing the powdery raw material to be classified into the supply pipe together with the air flow, a method of applying a pressure of 0.1 to 3 kg / cm ² is applied, and a blower located downstream of the classification zone is enlarged to reduce the load of the classification zone. A method of naturally suctioning the outside air and the powder raw material by increasing the pressure, or a method of attaching an injection feeder to the raw material powder input port, thereby sucking the raw material powder and the outside air and sending the powder to the classification zone via a supply pipe. There is.

In the present invention, among the above-mentioned charging means,
In particular, it is advantageous and preferable to use a method in which the negative pressure in the classification zone is increased and the outside air and the powder raw material are naturally suctioned, or a method using an injection feeder is used in terms of equipment and operating conditions. In addition, the classification of a toner that requires high-precision classification can be more effectively performed, and a favorable effect can be obtained in the classification of a toner having a weight average particle diameter of 10 μm or less. In particular, a weight average particle size of 7
In the classification of toner having a size of μm or less, a further effect can be obtained.

The classification operation in the multi-division classification region having the above-described configuration is performed, for example, as follows. That is,
The pressure in the classification area is reduced through at least one of the outlets 158, 159, and 160, and the raw material powder is supplied through the raw material supply pipes 148 and 149 at a flow rate of 50 to 300 m / sec by the airflow flowing by the reduced pressure. To supply. That is, if the first fine powder is supplied to the classification area at a flow rate of less than 50 m / sec, it is difficult to sufficiently disperse the fine powder, and it is easy to cause a decrease in classification yield and classification accuracy. When the first fine powder is supplied to the classification region at a flow rate exceeding 300 m / sec, the particles tend to be pulverized due to collision of the particles and ultrafine particles are easily generated, which tends to cause a decrease in the classification yield, and is thus preferable. Absent.

By the means described above, the powdered raw material composed of the first fine powder obtained in the first classifying step is supplied with the Coanda effect by the action of the Coanda block 145 and the action of gas such as air flowing in at that time. In accordance with the size of each particle size, large particles (particles having a particle size exceeding the specified particle size) move outside the airflow, that is, the first fractionation area outside the classification edge 147. In the meantime, the intermediate particles (particles within the standard size) are the second particles between the classification edges 146 and 147.
In the fractionation area, small particles (particles smaller than the standard particle size) are divided into third fractionation areas inside the classification edge 146, and large particles (coarse powder) are discharged from the outlet 158 to intermediate particles (medium powder). The body is discharged from the outlet 159, and the small particles (fine powder) are discharged from the outlet 160.

In order to carry out the above-described method, the above-described devices are connected to each other by a communication means such as a pipe, and used as an integrated device system as shown in FIG. That is, the classifier 27 in the apparatus system shown in FIG. 2 is as shown in FIG. 12, and the vibration feeder 25 and the collecting cyclones 29, 30 and 31 are connected to each other by communication means.

In the present invention, the first classifying means has a horizontal rotor, and the fine powder collection pipe uses a rotary airflow classifying means in which a part of the fine powder collecting pipe penetrates the horizontal rotating rotor. Since a pulverized fine powder having a particle size distribution is obtained, a classified product (product) having a more precise particle size distribution can be obtained by using such an air classifier.

The manufacturing method as described above has an effect on the image stability of a halftone image particularly when the following toner is manufactured.

That is, the weight average particle size (D ₄ ) is 3.5 to
A weight% is 6.5 μm, and the ratio remaining on the 200 mesh when the toner is sieved by a suction method is A weight%;
Assuming that the proportion remaining on the 500 mesh is B wt%, the toner is characterized in that A is 0.15 wt% or less and BA is 0.02 to 0.3 wt%. By using this, a high-quality halftone image can be obtained with a stable image density from a high-temperature and high-humidity environment to a low-temperature and low-humidity environment, and a high-quality image without deterioration due to fusion of the toner to the photoconductor can be obtained.

In the present invention, the toner has a weight average particle size D ₄ of 3.5 to 6.5 μm.

Conventionally, it has been considered preferable that the toner has an appropriate chargeability not too low / not too high. However, the present inventors have found that the weight average particle size is 3.5 to 6.5 μm.
m, which is smaller than the conventional toner, and which is excessively charged compared to the conventional toner, the difference in charge amount between the low-temperature, low-humidity environment and the high-temperature, high-humidity environment is reduced due to the increase in the overall charging ability. It has been found that the stability of the image density of the halftone image increases.

As a result, by using the toner of the present invention, the difference in chargeability / developability on the toner carrier in a low-temperature and low-humidity environment to a high-temperature and high-humidity environment can be suppressed.

When the weight average particle diameter D _{4 of the} toner is less than 3.5 μm, a sufficient image density cannot be obtained. When the weight average particle diameter D _{4 of the} toner exceeds 6.5 μm, the effect of suppressing the difference in chargeability / developability on the toner carrier in a low-temperature and low-humidity environment to a high-temperature and high-humidity environment is insufficient.

For the same reason as above, if the volume average particle diameter Dv of the toner is less than 2.5 μm, a sufficient image density cannot be obtained. The volume average particle diameter Dv of the toner is 6.0
If it exceeds μm, the effect of suppressing the difference in chargeability / developability on the toner carrier in a low-temperature low-humidity environment to a high-temperature high-humidity environment is insufficient.

Further, in the present invention, the ratio of the toner remaining on the 200 mesh when the toner is sieved by the suction method is defined as A
A is less than 0.15% by weight, and B-A is 0.02% by weight, when the percentage remaining on the 500 mesh when the toner is sieved by the suction method is defined as B% by weight.
0.3% by weight of toner is used.

In the toner of the present invention, which is excessively charged as compared with the conventional toner, if particles having a large particle size remaining on the 200 mesh are present in the toner in an amount exceeding 0.15% by weight, the toner particles and the toner Local contact with the regulating member is hindered, resulting in insufficient control of charging in the circumferential direction of the toner carrier. Such parts have different developability from other parts, and are particularly streaky on halftone images. Image defects tend to occur easily, and it is necessary to control the amount of coarse particles to be greater than that of conventional toners. The toner of the present invention, which is excessively charged as compared with the conventional toner, has a tendency that the coating amount of the toner on the toner carrier is thinner than that of the conventional toner, which remains on the 200 mesh. It is believed that this is likely to cause streak-like image defects due to the presence of large coarse particles.

The particle size is set to a value such that it passes through 200 mesh and remains on 500 mesh, and is approximately 30 to 75.
The presence of toner particles having a relatively large particle diameter of μm can prevent fusion of the toner to the photoconductor, which is likely to occur when a toner having a small weight average particle diameter is used. The reason is not clear, but about 3
Particles having a relatively large particle diameter of 0 to 75 μm exhibit an appropriate polishing ability at the photosensitive member contact portion of the cleaner and scrape small toner particles having a large particle diameter strongly adhered to the photosensitive member surface,
It is believed that fusion of the toner to the photoreceptor surface can be prevented.

If BA is less than 0.02% by weight, the effect of preventing the toner from fusing to the photoreceptor is insufficient. B-
When A exceeds 0.3% by weight, the contact between the toner carrier and the toner regulating member and the toner on the toner carrier is locally prevented, and a portion where the charge control is insufficient in the circumferential direction of the toner carrier is generated. It will be easier. Such portions are different in developability from other portions, and are likely to cause stripe-like image defects on an image.

The present invention also relates to an image forming apparatus having at least a latent image holding member, a developing device for visualizing the latent image, and a cleaning device for removing the transfer residue on the latent image holding member. And a toner regulating member contacting the toner carrying member. The toner regulating member is made of a material having at least a surface material of silicone, and the toner having a particle size distribution as described above is used. By using an image forming apparatus characterized by the above, high-quality images can be obtained with high image density from a high-temperature and high-humidity environment to a low-temperature and low-humidity environment, and a high-quality image that does not deteriorate due to fusion of the toner to the photoconductor is obtained. An image is obtained.

Silicone is used as the surface material of the toner regulating member that comes into contact with the toner carrier. Conventionally, a urethane rubber having a positive charge property is mainly used in a developing device for developing a negative charge toner. On the other hand, silicone has negative chargeability. The moderate negative chargeability of this silicone controls the charge of a toner having a high chargeability, which is smaller than the conventional toner having a weight average particle size of 3.5 to 6.5 μm used in the present invention. It is possible to further reduce the difference in chargeability / developability on the toner carrier in a wet environment.

Further, a toner carrier having an average surface roughness (Ra) of 0.15 μm or less is used. By using a toner carrier having a relatively small surface roughness, the chance of charging the toner with silicone, which is a toner regulating member, is increased, and the control of toner charging by silicone works more effectively. Therefore, it is possible to minimize the difference in chargeability / developability on the toner carrier in a low-temperature low-humidity environment to a high-temperature high-humidity environment.

If the average roughness of the toner carrier exceeds 0.15 μm, in the developing device of the present invention, the control of charging by the silicone, which is a toner regulating member, becomes insufficient, and the above effects cannot be sufficiently obtained.

The constituent materials of the toner will be described in detail.

The kind of 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 product thereof; styrene-p-chlorostyrene copolymer. Coalescing,
Styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylate copolymer, styrene-methacrylate 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-based copolymers such as styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer; polyvinyl chloride, phenolic resin, natural modified phenolic resin, natural resin modified maleic resin, acrylic Resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, cumarone indene resin and petroleum resin can be used. Crosslinked styrenic resins are also preferred binder resins.

Examples of comonomers for the styrene monomer of the styrene copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, and the like.
Double such as dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide A monocarboxylic acid having a bond or a substituted product thereof; for example, a dicarboxylic acid having a double bond such as maleic acid, butyl maleate, methyl maleate, or dimethyl maleate and a substituted product thereof; for example, vinyl chloride, vinyl acetate, Vinyl esters such as vinyl benzoate; ethylene olefins such as ethylene, propylene and butylene; vinyl ketones such as vinyl methyl ketone and vinyl hexyl ketone; 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 cross-linking 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, Carboxylic acid esters having two double bonds such as ethylene glycol dimethacrylate and 1,3-butanediol dimethacrylate; divinyl compounds of divinylaniline, divinylether, divinylsulfide and divinylsulfone; and three or more vinyl groups. Can be used alone or as a mixture.

The binder resin of the toner used for pressure fixing includes low molecular weight polyethylene, low molecular weight polypropylene, ethylene-vinyl acetate copolymer, ethylene-
Acrylic ester copolymers, higher fatty acids, polyamide resins and polyester resins are mentioned. These are preferably used alone or as a mixture.

It is also preferable to include the following waxes in the toner from the viewpoint of improving the releasability from the fixing member at the time of fixing and improving the fixing property. Paraffin wax and its derivatives, microcrystalline wax and its derivatives, Fischer-Tropsch wax and its derivatives, polyolefin wax and its derivatives, carnauba wax and its derivatives, and the derivatives include oxides and block copolymers with vinyl monomers. , Graft-modified products. In addition, alcohol, fatty acid, acid amide, ester, ketone, hydrogenated castor oil and its derivatives,
Vegetable wax, animal wax, mineral wax, petrolactam and the like can also be used.

In the developing device of the present invention, it is particularly preferred that the toner has one or more endothermic peaks in the differential thermal analysis in the region of 60 to 120 ° C. (more preferably in the region of 60 to 100 ° C.). A toner having one or more endothermic peaks at 60 to 120 ° C. or lower in the differential thermal analysis is excellent in lubricity between the toner carrier and the toner regulating member, and provides more uniform charging to the toner. Therefore, the occurrence of streak-like image defects due to local charging failure as described above can be further suppressed. In addition, the chargeability of the toner is increased, and the difference between the chargeability and the developability on the toner carrier in a low-temperature and low-humidity environment to a high-temperature and high-humidity environment can be further reduced. When the toner has an endothermic peak below 60 ° C., the storage stability of the toner is low.

As a method for the toner having one or more endothermic peaks in the region of 120 ° C. or less in the differential thermal analysis, a method containing a wax having an endothermic peak in the region of 120 ° C. or less in the differential thermal analysis is preferable. Specific examples include the following.

Natural waxes such as paraffin wax and its derivatives, montan wax and its derivatives, microcrystalline wax and its derivatives, Fischer-Tropsch wax and its derivatives, polyolefin wax and its derivatives, carnauba wax, candelilla wax, rice wax and the like Derivatives and the like include oxides, block copolymers with vinyl monomers, and graft-modified products. In addition, alcohols such as higher aliphatic alcohols; fatty acids such as stearic acid and palmitic acid or compounds thereof; acid amides, esters, ketones, hydrogenated castor oil and derivatives thereof; Any of them can be used.

The endothermic peak in the differential thermal analysis was 1
A wax having a temperature of 20 ° C. or more may be used in combination.

Among the above, particularly preferred are polyolefin waxes having a small polarity, hydrocarbon waxes by the Fischer-Tropsch method, petroleum waxes and higher aliphatic alcohols. When these waxes are used, the occurrence of streak-like image defects due to local charging failure can be further suppressed, and the chargeability / development on the toner carrier in a low-temperature low-humidity environment to a high-temperature high-humidity environment Sex differences can be further reduced.

In the molecular weight distribution of the wax component contained in the toner measured by gel permeation chromatography (GPC), Mw / Mn is 1.0 to 1.0.
When it is within the range of 2.0, the generation of streak-like image defects due to local charging failure can be further suppressed, and the chargeability on the toner carrier in a low-temperature low-humidity environment to a high-temperature high-humidity environment / The difference in developability can be further reduced, which is particularly preferable.

The effect of the present invention is particularly effective when the toner is a magnetic toner containing a magnetic powder.

The magnetic material used in the toner of the present invention includes
Examples include metal oxides containing elements such as iron, cobalt, nickel, copper, magnesium, manganese, aluminum, and silicon. These magnetic particles are BET by nitrogen adsorption method.
The specific surface area is preferably from 1 to 30 mg ² / g, especially 2.5
~26mg ² / g is preferable.

The amount of the magnetic substance is 5 with respect to 100 parts by weight of the binder resin.
The amount is preferably 0 to 200 parts by weight, particularly preferably 60 to 150 parts by weight. If the amount is less than 50 parts by weight, the transportability is insufficient, and the toner layer on the toner carrier becomes uneven, which tends to cause image unevenness. On the other hand, when it exceeds 200 parts by weight, there is a tendency that a problem occurs in the fixing property.

The average particle size of the magnetic material is 0.05 to 1.
0 μm is preferable, and 0.1 to 0.6 μm is more preferable.
m, more preferably 0.1 to 0.4 μm.

Further, the shape of the magnetic body is preferably substantially spherical. The term “substantially spherical” refers to a powder having a ratio of the major axis to the minor axis (major axis / minor axis) of 1.0 to 1.2. Take a 30,000-fold or more photograph of the magnetic powder with an electron microscope, measure the major axis and minor axis of at least 100 of them, and calculate the major axis / minor axis ratio with the average of the major axis / minor axis ratio.
The minor axis ratio is assumed.

The use of substantially spherical magnetic powder is particularly preferable because the difference in chargeability / developability on the toner carrier in a low-temperature low-humidity environment to a high-temperature high-humidity environment can be further reduced.

In the case of a magnetic toner, the absolute value of the charge amount of the toner with respect to iron powder is 40 mC / kg or more (more preferably 45 mC / kg or more, more preferably 50 mC / kg or more).
C / kg or more). As described above, by using the magnetic toner having a higher charging ability as compared with the related art, the charging property from a high temperature and high humidity environment to a low temperature and low humidity environment can be improved.
It is possible to further reduce the difference in developability.

As the coloring agent, conventionally known inorganic and organic dyes and pigments can be used in addition to the magnetic substance.
For example, carbon black, aniline black, acetylene black, naphthol yellow, hansa yellow,
There are Lodamun Lake, Alizarin Lake, Bengala, Phthalocyanine Blue, Induslen Blue and the like. These are usually used in an amount of 0.5 to 20 parts by weight based on 100 parts by weight of the binder resin.

In the toner of the present invention, it is preferable that a charge control agent is mixed (internally added) to the toner particles or mixed (externally added) with the toner particles before use. The charge control agent enables optimal charge control according to the development system.
In particular, in the present invention, it is possible to further stabilize the balance between the particle size distribution and the charge amount. The following substances control the toner to be negatively charged.

For example, organic metal complexes and chelate compounds are effective, and examples thereof include monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid-based metal complexes. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

The following substances can be controlled to be positively charged.

Modified products of nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and phosphonium salts which are analogs thereof Onium salts such as, for example, these lake pigments, triphenylmethane dyes and these lake pigments (as the lacking agent, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanic acid) , Ferrocyanide, etc.), metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyl Diorgano tin borate such as Suzuboreto; can be used in combination singly or two or more kinds.

The charge control agents described above are preferably used in the form of fine particles. In this case, the number average particle size of these charge control agents is particularly preferably 4 μm or less, more preferably 3 μm or less. When these charge control agents are internally added to the toner, it is preferable to use 0.1 to 20 parts by weight, particularly 0.2 to 10 parts by weight, based on 100 parts by weight of the binder resin.

The toner of the present invention is obtained by mixing an inorganic fine powder having been subjected to an organic treatment with toner particles by a mixer such as a Henschel mixer in order to improve environmental stability, charging stability, developability, fluidity and storage stability. By mixing, the toner of the present invention is obtained.

The inorganic fine powder used in the present invention includes:
Fine inorganic powders such as fine silica powder, titanium oxide and aluminum oxide are preferred, and fine silica powder is particularly preferred.
For example, as the silicic acid fine powder, both a so-called dry method produced by vapor phase oxidation of a silicon halide or a dry silica called fumed silica, and a so-called wet silica produced from water glass or the like can be used. There is
Dry silica having less silanol groups on the surface and in the interior of the silica fine powder and having less production residues such as Na ₂ O and SO ₃ ^2- is preferred. In the case of fumed silica, for example, aluminum chloride, titanium chloride,
By using other metal halide compounds together with a silicon halide compound, it is also possible to obtain a composite fine powder of silica and another metal oxide, and these are also included.

The inorganic fine powder may be treated with an organic metal compound such as a silane coupling agent or a titanium coupling agent which reacts or physically adsorbs with the inorganic fine powder, or may be treated with a silane coupling agent. Later, or simultaneously with treatment with a silane coupling agent, treatment with an organosilicon compound such as silicone oil may be mentioned.

Examples of the silane coupling agent used in the organic treatment include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, and allylphenyldisilane. Chlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilyl acrylate, vinyldimethylacetoxy Silane, dimethyldiethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1, 3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane,
And dimethylpolysiloxane having from 2 to 12 siloxane units per molecule and having a hydroxyl group bonded to one silicon atom at each terminal unit.

Also, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane, dibutylaminopropyltrimethoxysilane, Butylaminopropyltrimethoxysilane, dioctylaminopropyldimethoxysilane, dibutylaminopropyldimethoxysilane,
Silane coupling agents such as dibutylaminopropylmonomethoxysilane, dimethylaminophenyltriethoxysilane, trimethoxysilyl-γ-propylphenylamine, and trimethoxysilyl-γ-propylbenzylamine are also used alone or in combination. Preferred silane coupling agents include hexamethyldisilazane (H
MDS).

As the organosilicon compound, silicone oil can be used. As preferred silicone oils, those having a viscosity at 25 ° C. of 0.5 to 10,000 centistokes, preferably 1 to 1,000 centistokes are used. For example, dimethyl silicone oil,
Methylphenyl silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, fluorine-modified silicone oil and the like are particularly preferred. As a method of the silicone oil treatment, for example, silica fine powder treated with a silane coupling agent and silicone oil may be directly mixed using a mixer such as a Henschel mixer, or silicone fine powder serving as a base may be mixed with silicone fine powder. A method of spraying oil may be used. Alternatively, a method of dissolving or dispersing a silicone oil in an appropriate solvent, adding a silica fine powder, mixing and removing the solvent may be used.

[0110] used in the present invention the organic-treated inorganic fine powder has a specific surface area by nitrogen adsorption measured by BET method is 30 m ² / g or more, in particular 50 to 400 m ² / g good results in the range of The inorganic fine powder subjected to the hydrophobic treatment to be used in the present invention may be used in an amount of 0.01 to 8 parts by weight, preferably 0.1 to 5 parts by weight, particularly preferably 0.1 to 5 parts by weight based on 100 parts by weight of the toner particles. Preferably, 0.2 to 3 parts by weight is good. When the amount is less than 0.01 part by weight, the effect of improving toner aggregation is poor. When the amount is more than 8 parts by weight, problems such as toner scattering between fine lines, contamination in the apparatus, and scratches and abrasion of the photoconductor tend to occur. is there.

The toner of the present invention may further contain other additives within a range that does not substantially adversely affect the toner, for example, lubricant powders such as Teflon (registered trademark) powder, zinc stearate powder, and polyvinylidene fluoride powder; cerium oxide Abrasives such as powder, silicon carbide powder and strontium titanate powder; fluidity-imparting agents such as titanium oxide powder and aluminum oxide powder; anti-caking agents; or conductive materials such as carbon black powder, zinc oxide powder and tin oxide powder. A small amount of a property imparting agent or organic and inorganic fine particles of opposite polarity can also be used as a developing property improver.

To prepare the toner according to the present invention, a binder resin, a wax, a metal salt or a metal complex, a pigment, a dye, or a magnetic substance as a colorant, a charge control agent, if necessary, and other additives After mixing thoroughly with a mixer such as a Henschel mixer or a ball mill, a heating roll, a kneader, and a metal compound while melting and kneading the resins with each other using a hot kneader such as an extruder,
The toner according to the present invention can be obtained by dispersing or dissolving a pigment, a dye, and a magnetic substance, cooling and solidifying, pulverizing and classifying. In the classification step (second classification means), it is preferable to use a multi-segment classifier as described above in terms of production efficiency.

Particularly, the toner used in the developing device of the present invention is
Since the proportion of the coarse particles having a specific particle size in the toner needs to be within a specific range, the first ratio in the pulverizing step is required.
The classification process has a horizontal type rotor, and the fine powder recovery pipe introduces the pulverized raw material into a rotary airflow classification means partially intruding into the horizontal type rotary rotor to classify it into fine powder and coarse powder. The classified fine powder is introduced into a second classifying step to classify and obtain a classified product for producing a toner, and the coarse powder classified in the first classifying step is used as a material to be pulverized. Member having an accelerating tube for conveying and accelerating the object and a pulverizing chamber for finely pulverizing the object to be pulverized, and having a collision surface provided in the pulverizing chamber so as to face an opening surface of an outlet of the accelerating tube. Is provided at the rear end of the accelerating tube, a pulverized material supply port for supplying the object to be pulverized into the accelerating tube, and the collision surface is provided at a protruding central portion whose center protrudes and an outer periphery thereof. With the outer peripheral collision surface in the shape of a cone, Further pulverized and introduced into collision type air pulverizer means having a sidewall for grinding by the collision of the object to be crushed that is, first by the fine pulverized product was mixed into the powder material
The amount of the coarse particles of the toner can be controlled by a manufacturing method in which the toner is re-introduced into the classification step and is subjected to the circulation treatment.

The configuration of the image forming apparatus will be described in detail.

An image forming apparatus to which the image forming method of the present invention is applied includes, for example, an apparatus as shown in FIG. Hereinafter, a specific description will be given with reference to the drawings. In FIG. 13, reference numeral 200 denotes a photosensitive drum, around which a primary charging roller 217, a developing device 240, a transfer charging roller 214, a cleaner 216, a register roller 224, and the like are provided. Then, the photosensitive drum 200 is charged by the primary charging roller 217. Then, the laser beam 223 is applied to the photosensitive drum 2 by the laser generator 221.
It is exposed by irradiating 00. Photosensitive drum 2
The electrostatic latent image on 00 is developed with a one-component magnetic toner by a developing device 240 and is transferred onto a transfer material by a transfer roller 214. The transfer material having the toner image thereon is conveyed to a fixing device 226 by a conveyor belt 225 or the like, and is fixed on the transfer material. Further, the toner left partially on the photosensitive drum 200 is cleaned by the cleaning unit 216.

The structure of the developing device will be described in more detail.

In FIG. 14, the toner carrier 321 has a substantially right half peripheral surface constantly in contact with the toner reservoir in the toner container 322, and the toner near the surface of the toner carrier 321 is placed on the toner carrier surface. It is attached and held by the magnetic force and / or the electrostatic force of the magnetism generating means (magnetic roll) 323. When the toner carrier 321 is rotationally driven, the toner layer 24 on the surface of the toner carrier 321 passes through the position of the toner regulating member 325, and is layered / charged to a uniform thickness in each portion. . As the toner carrier 321 rotates, the toner layer on the toner carrier
26, and passes through the developing area A, which is the closest part between the photoconductor 326 and the toner carrier 321. During this passage, the toner in the toner layer on the surface side of the toner carrier 321 is transferred to the photoconductor by the bias applied between the photoconductor 326 and the toner carrier 321, and the development is performed according to the potential pattern of the latent image. Done.

The toner carrier surface on which the magnetic toner has been selectively consumed after passing through the developing area A is placed in the toner container 32.
The toner is re-supplied by re-rotating into the second toner reservoir, and the developing process is repeatedly performed.

Silicone is used as the material of the toner regulating member that contacts the toner carrier used in the present invention. Among silicones, silicone rubber having elasticity is particularly preferable as a material. Also, organic compounds in silicone,
An inorganic compound may be added, melt-mixed, or dispersed. For example, metal oxides, metal powders,
Ceramics, allotropes, whiskers, inorganic fibers, dyes, pigments, surfactants, etc.

As a method for bringing the toner regulating member into contact with the toner carrier, in addition to a method in which an elastic silicone rubber blade is brought into contact with the toner carrier, there is also a method in which silicone is applied to the toner carrier with another elastic material such as metal. A method of pasting on the contacting part may be used.

The base on the upper side of the toner regulating member is fixedly held to the toner container side, and the lower side is opposed to the opposite direction of the toner carrier as shown in FIGS. 15 and 16 against the elasticity of the blade. It is bent in the forward direction and is brought into contact with the surface of the toner carrier with an appropriate elastic pressure.

The contact pressure between the toner regulating member and the toner carrier is 4.9 to 11 as a linear pressure in the toner carrier generatrix direction.
8 N / m is effective. If the contact pressure is less than 4.9 N / m, the control of charging of the toner by the silicone becomes insufficient, and the toner coat tends to be uneven in a low humidity environment. On the other hand, if the contact pressure exceeds 118 N / m, a large pressure is applied to the toner, and the toner is likely to deteriorate.

The toner carrier used in the present invention has an average surface roughness of 1.5 μm or less (more preferably 1.3 μm or less).

As the material of the toner carrier, a metal such as aluminum or SUS, or a material such as ceramics is used. The toner carrier can be used as it is drawn or cut, but it can be polished, roughened in the circumferential or longitudinal direction, blasted, or coated to have an average surface roughness of 1.
If it is 5 μm or less, it may be performed.

In the developing device of the present invention, it is preferable that a resin coating layer containing conductive fine particles is formed on the surface of the toner carrier. When a resin coating layer containing conductive fine particles is formed on the surface of the toner carrier, a specific developing device of the present invention can control the toner charge by the resin coating layer, so that a low temperature and low humidity environment The difference in chargeability / developability on the toner carrier in a high temperature and high humidity environment can be further reduced.

Examples of the conductive fine particles contained in the resin layer covering the surface of the toner carrier include conductive metal oxides such as carbon black, graphite, and conductive zinc oxide, and metal double oxides, alone or in combination of two or more. It is preferably used. In addition, a form in which particles having an appropriate particle size are contained for the purpose of controlling the surface roughness of the resin coating layer is also preferable.
As the resin, a resin such as a phenol resin, an epoxy resin, a polyamide resin, a polyester resin, a polycarbonate resin, a polyolefin resin, a silicone resin, a fluorine resin, a styrene resin, and an acrylic resin is used. be able to. Particularly, a thermosetting or photocurable resin is preferable.

As the cleaning method used in the image forming apparatus of the present invention, blade cleaning is preferable. Blade cleaning is performed by using urethane rubber, silicone rubber, or elastic resin as a blade, or by holding a chip-shaped resin at the tip of a blade made of metal or the like in the forward or reverse direction with respect to the moving direction of the photoconductor. It is known as abutted or pressed. Preferably, the blade is pressed against the moving direction of the photoreceptor in the opposite direction. At this time, the contact pressure with the blade against the photoconductor is preferably 4.9 N / m or more as a linear pressure, and more preferably 9.8 to 49 kg / m. Further, a mag brush cleaning method, a fur brush cleaning method, a roller cleaning method, or the like may be combined with the blade cleaning method.

As a method of sieving the toner by a suction method and measuring the ratio remaining on 200 mesh / 500 mesh, the same device as the device for measuring the charge amount shown in FIG. 17 is used. At this time, a metal screen having a mesh whose weight (w1 (g)) was precisely weighed in advance is used for the bottom. The toner w2 is placed in the measurement container 452 with the mesh attached to the bottom.
(G). Next, the measurement container is placed on a suction machine without a lid, and the container is suctioned from the suction port 457. In this state, the container is vibrated strongly from outside using a metal rod or the like for about 2 minutes.
Suction thoroughly and screen.

After the suction is completed, the mesh is carefully removed from the container, and the total weight (w3 (g)) of the mesh and the residue remaining thereon is precisely weighed. The ratio M of the toner remaining on the mesh by the suction method is determined by the above formula of M (%) = ((w3-w1) / w2) × 100.

The average particle size and particle size distribution of the toner can be measured by various methods such as Coulter Counter TA-II or Coulter Multisizer (manufactured by Coulter). In the present invention, Coulter Multisizer (manufactured by Coulter) is used. Is connected to an interface (manufactured by Nikkaki) that outputs the number distribution and volume distribution and a PC9801 personal computer (manufactured by NEC).
A 1% NaCl aqueous solution is prepared using graded sodium chloride. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) can be used. As a measurement method, 0.1 to 5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution, and the measurement sample is added to 2 to 100 ml.
Add ~ 20 mg. The electrolytic solution in which the sample was suspended was subjected to dispersion treatment for about 1 to 3 minutes using an ultrasonic disperser, and the volume and the number of toner particles having a size of 2 μm or more were measured using the Coulter Multisizer with an aperture of 100 μm. The number distribution was calculated. Then, the weight-based weight average particle diameter (D ₄ : the median value of each channel is a representative value of the channel) and the volume average particle diameter (D _v : median value of each channel) obtained from the volume distribution according to the present invention. Channel representative value).

The method for measuring the charge amount of the toner according to the present invention will be described below with reference to FIG.

Under an environment of 23 ° C. and a relative humidity of 60%, a mixture of 10.0 g of carrier and 0.5 g of toner added to 10.0 g of carrier was used as a carrier in a polyethylene bottle having a volume of 50 to 100 ml using EFV200 / 300 (Powdertech). And shake by hand 50 times. Then, about 0.5 g of the mixture is placed in a metal measuring container 452 having a 500-mesh screen 453 at the bottom, and a metal lid 454 is provided.
At this time, the weight of the entire measurement container 452 is weighed and defined as W ₁ (g). Next, in a suction machine (at least a portion in contact with the measurement container 452 is at least an insulator), the air is suctioned from the suction port 457 and the air volume control valve 456 is adjusted to reduce the pressure of the vacuum gauge 455 to 2450
Pa (250 mmAq). In this state, suction is performed for one minute to remove the toner by suction. Electrometer 459 at this time
Is V (volt). Here, 458 is a capacitor whose capacity is C (μF). The weight of the whole measuring container after the suction is weighed and defined as W ₂ (g). The triboelectric charge (mC / kg) of this toner is calculated as shown in the following equation.

A triboelectric charge (mC / kg) = CV / (W ₁ −W ₂ )

[0134]

The following "parts" means "parts by weight".

Example 1 The following was used as a developing device.

As a toner carrier, carbon black, graphite, and acrylic resin particles were placed on the surface of a sleeve of an aluminum cylindrical tube (outer diameter: 16 mm) as drawn out in 10 parts of a phenol resin in a ratio of 1: 9: 0. One coated with a resin coating layer dispersed at a ratio of 1 (average surface roughness: 1.0 μm) was used. In addition, a quadrupole magnet having a magnetic flux density of a developing pole of 80 mT was built in the cylindrical sleeve. The thickness of the toner regulating member is 1.5
Using a silicone rubber blade having a thickness of 3 mm, the toner carrier was brought into contact with the toner carrier at a drawing pressure of 34.3 N / m as shown in FIG.

As the photoconductor, an organic photoconductor having a diameter of 30 mm was used, and the closest distance between the toner carrier and the photoconductor was 3 mm.
It was set to 00 μm.

A roller charger is used as a primary charger, a laser beam is used as an exposure means, and 600 dpi.
Formed a latent image. A roller charger was used as the transfer charger.

[0139] A blade cleaning device was used as a cleaning device for removing toner remaining on the photoreceptor in the transfer step, and a urethane blade was used as a cleaning blade.

The potential of the latent image on the photoreceptor is -7
The voltage was set so as to be 00 V and the bright portion potential was -150 V.

The photosensitive member was rotated at 72 mm / s. The toner carrier was also rotated at 72 mm / s.

A rectangular wave having a DC voltage of -500 V, an AC voltage of 1600 V (peak-to-peak) and an AC frequency of 2200 Hz was applied as a developing bias to the toner carrier.

A toner was prepared in the following procedure.・ Styrene-n-butyl acrylate-monobutyl acrylate maleate 100 parts ・ Magnetic iron oxide (shape: spherical (major axis / minor axis: 1.05)) 100 parts ・ Low molecular weight polyethylene (melting point: 95 ° C., Mw / Mn: 1.3) 7 parts-Monoazo iron complex 2 parts After the above materials were premixed, melt kneading was performed by a twin screw kneading extruder set at 110 ° C. After cooling the kneaded material, it was coarsely pulverized, and the obtained toner raw material was finely pulverized and classified by the apparatus system shown in FIG. 6 is used as the collision type air flow crusher 28. In the collision type air flow crusher, the position of the tip of the protruding central portion that enters the acceleration tube is 10 mm (L ₁ = 10 mm), and the crushing chamber is used. The diameter of the front wall is 154 mm (B = 154 mm), and the diameter of the rear wall of the crushing chamber is 136 mm (C = 136 mm).

Here, the collision member 51 shown in FIG. 10 was used. The collision member 51 has α = 55 °, β = 1
A crushing chamber 53 having a diameter of 0 ° and an outer diameter (diameter) of 100 mm was used.
As the first classification means 22, a rotary airflow classifier having a configuration shown in FIGS. 3 and 4 was used. The diameter L1 of the classifying rotor 124 is 200 mm, and the amount of the fine powder collection tube entering the classifying rotor is 3 mm.
It was set at 0 mm and used. In addition, the classification rotor 124
Was 2,800 rpm.

In the present embodiment, first, the powdery raw material composed of the coarsely pulverized material is fed to the table-type first constant-quantity feeder 21 for 35.
It was supplied to the rotary airflow classifier 22 having the configuration shown in FIG. 3 through the supply pipe 125 by the injection feeder 35 at a rate of 0 kg / h, and was classified into coarse powder and fine powder. The coarse powder classified by the classifier is fed to a coarse powder discharge hopper 13.
The impingement type airflow pulverizer 28 having the configuration shown in FIG.
And pulverized. Pulverized material supply pipe 4 of pulverizer 28
The coarse powder supplied from No. 1 has a pressure of 6.0 kg / cm.
² (G), after being pulverized using compressed air of 6.0 Nm ³ / min, mixed with the powder raw material for toner production supplied in the raw material introduction section, again serving as the first classification means. The mixture was introduced into the airflow classifier 22 to perform closed-circuit pulverization. On the other hand, the fine powder classified by the rotary airflow classifier 22 in the first classification step is collected by the cyclone 23 while being accompanied by the suction air from the exhaust fan 131, and is introduced into the second quantitative feeder 24. .

Next, the fine powder obtained by the classification by the rotary airflow classifier 22 of the first classifying means is introduced into the second quantitative feeder 24, and is passed through the vibrating feeder 25 and the nozzles 148 and 149. Classifier 27 having the configuration of FIG. 12 of the second classification process at a rate of 30.0 kg / h.
Was introduced. In the classifier 27, the powder is classified into three types of particle sizes of coarse powder, medium powder and fine powder by utilizing the Coanda effect. When introducing into the three-segment classifier 27, the outlet 15
Collection cyclone 2 communicating with 8, 159 and 160
The suction force derived from the pressure reduction in the system by the suction pressure reduction at 9, 30, and 31 and the compressed air from the injection feeder 32 attached to the material supply nozzle 148 were used. The introduced fine powder was instantaneously classified into three types of coarse powder, medium powder and fine powder in 0.1 seconds or less. Among the classified materials, the coarse powder was collected by the collection cyclone 29, introduced into the air-flow type fine pulverizer 28 described above, and introduced again into the pulverization step.

The middle powder (classified product) classified in the second classifying step had a weight average particle size of 5.4 μm.

1.8 parts of hydrophobic silica obtained by subjecting dry-process silica (BET specific surface area: 300 m ² / g) surface-treated with hexamethyldisilazane to hydrophobic treatment with dimethyl silicone oil, and 0.16 parts of the above-mentioned toner coarse particles Was mixed with 100 parts of the above black fine powder (medium powder) by stirring with a Henschel mixer, and sieved with a vibrating sieve equipped with a 150-mesh screen to obtain toner A.

When the weight average particle diameter (D ₄ ) of this toner A was measured, it was 5.4 μm. The measured amount of charge was -57 mC / kg. The ratio remaining on 200 mesh by the suction method is 0.003% by weight, 5% or less.
The percentage remaining on the 00 mesh was 0.155% by weight. The endothermic peak of the toner by differential thermal analysis is 95%.
° C.

The toner A was applied to the developing device main body, and an environment of 15 ° C./10RH% was used by using the image forming apparatus.
20,000 sheets were intermittently output in an environment of 32 ° C. and 80 RH%, and the image density and the vertical stripes of the solid image were evaluated.

The image density was evaluated using a "Macbeth reflection densitometer" (Macbeth) for a halftone image formed by horizontal lines of 1 dot / 2 space.

The number of vertical streaks appearing on the halftone image was visually counted and evaluated for the vertical streaks of the solid image.

The fusion of the toner to the photoreceptor is performed at 32 ° C./80.
In an environment of RH%, 20,000 images were continuously printed out, and the number of fusion generated on the photoreceptor was visually counted.

Table 2 shows the above evaluation results.

<Example 2> Fine pulverization and classification were carried out in the same apparatus system using the same toner raw material as in Example 1. That is, the impingement type air current pulverizer having the configuration shown in FIG. 6 was used, and pulverization was performed under the same apparatus conditions as in Example 1. As the second classification means 27, the same one as in Example 1 was used. As the first classifying means, the same rotary airflow classifier as in Example 1 was used, but the rotation speed of the classifying rotor was 3,100 rpm.
m. Next, this fine powder was introduced into the second classifying means 27 at a rate of 25.0 kg / h through the second quantitative feeder 24, and a classified product (medium powder) having a weight average particle size of 4.5 μm was obtained. Obtained.

Using this medium powder, toner B was obtained in the same manner as in Example 1, and evaluated under the physical properties and conditions shown in Table 1 in the same manner as in Example 1, and the results shown in Table 2 were obtained.

<Example 3> Fine pulverization and classification were performed using the same toner system as in Example 1 and the same apparatus system. That is, the impingement type air current pulverizer having the configuration shown in FIG. 6 was used, and pulverization was performed under the same apparatus conditions as in Example 1. As the second classification means 27, the same one as in Example 1 was used. As the first classifying means, the same rotary airflow classifier as in Example 1 was used, but the number of rotations of the classifying rotor was set to 2300 rpm.
And In the present embodiment, 32.0 kg of powder raw material was used.
/ H was supplied to the above-mentioned apparatus system, and a fine powder having a weight average particle diameter of 6.4 μm was obtained by the first classification step and the pulverization step. Next, the fine powder is introduced into the second classifying means 27 at a rate of 25.0 kg / h through the second metering device 24,
A classified product (medium powder) having a weight average particle size of 6.2 μm was obtained.

Using this medium powder, a toner C was obtained in the same manner as in Example 1, and evaluated in the same manner as in Example 1 under the physical properties and conditions shown in Table 1, and the results shown in Table 2 were obtained.

<Example 4> Fine pulverization and classification were carried out using the same toner raw material as in Example 1 and using an apparatus system which was changed to an impingement airflow pulverizer. That is, FIG.
The pulverization was performed under the same apparatus conditions as in Example 1 using the configuration shown in FIG. As the second classification means 27, the same one as in Example 1 was used. In addition, the same rotary classifier as in Example 1 was used as the first classifying means, but the number of revolutions of the classifying rotor was set at 2750 rpm. In this example, a powder raw material was supplied to the above-mentioned apparatus system at a rate of 32.0 kg / h, and a fine powder having a weight average particle size of 5.4 μm was obtained by the first classifying step and the pulverizing step. Next, this fine powder was introduced into the second classifying means 27 at a rate of 25.0 kg / h through the second quantitative feeder 24, and a classified product (medium powder) having a weight average particle size of 6.2 μm was obtained. Obtained. Using this medium powder, a toner D was obtained in the same manner as in Example 1, and evaluated in the same manner as in Example 1 under the physical properties and conditions shown in Table 1, and the results shown in Table 2 were obtained.

<Comparative Example 1> Fine pulverization and classification were performed using the same toner raw material as in Example 1 using the apparatus system shown in FIG. However, the first classifying means having the structure shown in FIGS. 3 and 5 was used. The second classifying means 27 used was the same as that used in Example 1.

Using the obtained intermediate powder, a toner E was obtained in the same manner as in Example 1, and the physical properties and conditions shown in Table 1 were used to obtain a toner E.
Evaluation was performed in the same manner as described above, and the results shown in Table 2 were obtained.

<Comparative Example 2> Using the same toner raw material as in Example 1, fine pulverization and classification were performed in the apparatus system shown in FIG. However, the first classifier having the structure shown in FIGS. 3 and 4 was used. However, the penetration depth of the fine powder collection tube into the classification rotor was 1 mm. The second classifying means 27 used was the same as that used in Example 1.

Using the obtained intermediate powder, a toner F was obtained in the same manner as in Example 1, and the physical properties and conditions shown in Table 1 were used to obtain toner F.
Evaluation was performed in the same manner as described above, and the results shown in Table 2 were obtained.

<Comparative Example 3> Using the same toner raw material as in Example 1, fine pulverization and classification were performed in the apparatus system shown in FIG. As the first classification means, those having the configurations shown in FIGS. 3 and 4 were used. However, the penetration depth of the fine powder collection tube into the classification rotor is 5
00 mm. The second classifying means 27 used was the same as that used in Example 1.

Using the obtained intermediate powder, a toner G was obtained in the same manner as in Example 1, and the physical properties and conditions shown in Table 1 were used to obtain toner G.
Evaluation was performed in the same manner as described above, and the results shown in Table 2 were obtained.

<Comparative Example 4> The mesh for sieving the toner was 50
Toner H was obtained in the same manner as in Example 1 with a mesh of 0. This toner was evaluated in the same manner as in Example 1, and the results shown in Table 2 were obtained.

<Examples 5 to 10> Evaluations were made in the same manner as in Example 1 using the same developing device as in Example 1 except that the wax contained in the toner was changed, and the results shown in Table 2 were obtained.

Example 11 The same evaluation as in Example 1 was performed using the same developing device as in Example 1 except that a urethane blade was used as the toner regulating member, and the results shown in Table 2 were obtained.

Examples 12 to 14 Evaluations were made in the same manner as in Example 1 except that the average surface roughness (Ra) was changed by changing the amount of the acrylic resin particles in the toner carrier. The result was obtained.

[0170]

[Table 1]

[0171]

[Table 2]

[0172]

As described above, according to the method of the present invention for producing toner particles, an excellent toner having a small particle size and a sharp predetermined particle size, particularly on the coarse side, can be produced at a lower cost than the conventional method. Thus, an excellent image having a stable and high halftone image density can be obtained. In particular, according to the present invention, a toner having a sharp particle size distribution can be efficiently obtained from a raw material having a weight average diameter of 10 μm or less, and further, a toner having a small particle diameter can be obtained from a raw material having a weight average diameter of 7 μm or less. It is possible to efficiently obtain a toner having a sharp particle size distribution.

[Brief description of the drawings]

FIG. 1 is an example of a flowchart showing an outline of a method for producing toner particles.

FIG. 2 shows an example of an apparatus system for producing toner particles.

FIG. 3 is a schematic explanatory view of an airflow classifier.

FIG. 4 is an enlarged sectional view of a classification rotor and a fine powder discharge pipe of the airflow classifier of the present invention.

FIG. 5 is an enlarged sectional view of a classification rotor and a fine powder discharge pipe of a conventional airflow classifier.

FIG. 6 is a schematic explanatory view of a collision type airflow pulverizer.

FIG. 7 is a sectional view taken along line A-A 'of FIG.

8 is a sectional view taken along line B-B 'of FIG.

FIG. 9 is a sectional view taken along line C-C 'of FIG.

FIG. 10 is an explanatory view of a collision member.

FIG. 11 is a schematic explanatory view of a collision type airflow pulverizer.

FIG. 12 is an explanatory diagram of a multi-divider classifier suitable as a second classifier of the present invention.

FIG. 13 is a diagram illustrating an example of an image forming apparatus used in the present invention.

FIG. 14 is an explanatory diagram of a developing device.

FIG. 15 is a diagram illustrating one mode of contact of an elastic blade with a toner carrier.

FIG. 16 is a diagram illustrating one mode of contact of an elastic blade with a toner carrier.

FIG. 17 is an explanatory diagram of an apparatus for measuring a charge amount.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Acceleration pipe 2 Throat part 3 High-pressure gas supply nozzle 5 Object to be pulverized 10 Acceleration pipe outlet 11 Collision member 13 Pulverization chamber 16 Side wall 28 Collision type airflow pulverizer 121 Main body casing 122 Classification chamber 123 Guide chamber 124 Horizontal rotary rotor 129 Fine powder discharge pipe 136 Clearance 200 Photosensitive drum 240 Developing device

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H005 AA02 AA06 AB04 CA13 CA14 DA02 DA07 EA01 EA03 EA05 EA06 FA06 2H077 AD06 AD12 EA11 FA01 FA12

Claims (26)

[Claims] 1. A mixture containing at least a binder resin and a colorant is melt-kneaded, and after cooling the obtained kneaded product,
A rotary airflow classifier that has a horizontal rotary rotor, and a fine powder collection pipe partially penetrates the horizontal rotary rotor, for a powder raw material comprising a coarsely pulverized product obtained by pulverizing a cooled product by a pulverizing means. Introduced into a first classification step using means to classify into fine powder and coarse powder, and then introduced into a second classification step to classify the fine powder to obtain a classified product for producing toner particles. In addition, the coarse powder classified in the first classification step is introduced as an object to be pulverized into an impingement type air current pulverization means and finely pulverized. A method for producing toner particles, comprising introducing and circulating. 2. The crushing airflow crushing means has an accelerating tube for conveying and accelerating the object to be crushed by a high-pressure gas and a crushing chamber for finely crushing the object to be crushed. A collision member having a collision surface provided opposite to the opening surface of the outlet of the tube is provided, and a rear end portion of the acceleration tube has a material supply port for supplying the material to be ground into the acceleration tube. The collision surface has a shape consisting of a projecting central portion whose center is protruded and a cone-shaped outer peripheral collision surface provided on the outer periphery thereof, and further the crushed object crushed by the collision member in the crushing chamber. 2. The method for producing toner particles according to claim 1, wherein the method is a collision-type airflow pulverization unit having a side wall for further pulverization by collision. 3. A high-pressure gas supply nozzle for supplying a high-pressure gas and a high-pressure gas supplied from the high-pressure gas supply nozzle for conveying and accelerating the object to be ground in the acceleration tube. An accelerating tube, a pulverizing chamber for finely pulverizing the material to be pulverized discharged from the outlet of the accelerating tube, and a pulverized material discharged from the outlet of the accelerating tube provided at a position in the pulverizing chamber facing the outlet of the accelerating tube. A collision type airflow pulverizing means having at least a collision member for pulverizing an object, wherein the collision member has a first collision surface protruding toward the acceleration tube at an apex angle α about a major axis of the acceleration tube. And a second collision surface inclined at an angle β with respect to a perpendicular to the long axis of the accelerating tube toward the downstream side, and the pulverizing chamber has an outermost edge portion of the second collision surface. A first side wall upstream of the first side wall and a first side wall downstream of the first side wall; And at least a second side wall extending downstream.
So that the crushing chamber on the upstream side of the outermost edge of the collision surface has a portion having a larger cross-sectional area on the crushing chamber side than the cross-sectional area on the crushing chamber side corresponding to the outermost edge of the second collision surface. 2. The airflow pulverizing means according to claim 1, wherein the first collision surface is enlarged, and a tip of the first collision surface is located upstream of a downstream end of the first side wall. Production method of toner particles. 4. A rotary airflow classifier, wherein said rotary airflow classifier has a plurality of blades arranged at regular intervals on the same circumference, wherein said horizontal rotary rotor has a diameter X of 100.
4. The method according to claim 1, wherein the fine powder discharge pipe has a penetration portion X2 of 5 × 10 ^-3 to 2 × 10 ^-1 m into the horizontal rotary rotor. Production method of toner particles. 5. A mixture containing at least a binder resin and a colorant is melt-kneaded, and after cooling the obtained kneaded product,
A rotary airflow classifier that has a horizontal rotary rotor, and a fine powder collection pipe partially penetrates the horizontal rotary rotor, for a powder raw material comprising a coarsely pulverized product obtained by pulverizing a cooled product by a pulverizing means. Introduced into a first classification step using means to classify into fine powder and coarse powder, and then introduced into a second classification step to classify the fine powder to obtain a classified product for producing toner particles. In addition, the coarse powder classified in the first classification step is introduced as an object to be pulverized into an impingement type air current pulverization means and finely pulverized. A toner produced by a method for producing toner particles to be introduced and circulated, wherein the toner has a weight average particle size (D ₄ ) of 3.5 to 6.5 μm.
And 200 when the toner is sieved by the suction method.
When the ratio remaining on the mesh is A weight% and the ratio remaining on the 500 mesh is B weight%, A is 0.15%.
% By weight or less, and BA is 0.02 to 0.3% by weight. 6. A crushing airflow pulverizing means has an accelerating tube for conveying and accelerating an object to be pulverized by a high pressure gas and a pulverizing chamber for pulverizing the object to be pulverized. A collision member having a collision surface provided opposite to the opening surface of the outlet of the tube is provided, and a rear end portion of the acceleration tube has a material supply port for supplying the material to be ground into the acceleration tube. The collision surface has a shape consisting of a projecting central portion whose center is protruded and a cone-shaped outer peripheral collision surface provided on the outer periphery thereof, and further the crushed object crushed by the collision member in the crushing chamber. 6. The toner according to claim 5, wherein the toner is a collision-type airflow pulverization unit having a side wall for further pulverization by collision. 7. A high-pressure gas supply nozzle for supplying a high-pressure gas, and a high-pressure gas supplied from the high-pressure gas supply nozzle for conveying and accelerating an object to be ground in the acceleration tube. An accelerating tube, a pulverizing chamber for finely pulverizing the material to be pulverized discharged from the outlet of the accelerating tube, and a pulverized material discharged from the outlet of the accelerating tube provided at a position in the pulverizing chamber facing the outlet of the accelerating tube. A collision type airflow pulverizing means having at least a collision member for pulverizing an object, wherein the collision member has a first collision surface protruding toward the acceleration tube at an apex angle α about a major axis of the acceleration tube. And a second collision surface inclined at an angle β with respect to a perpendicular to the long axis of the accelerating tube toward the downstream side, and the pulverizing chamber has an outermost edge portion of the second collision surface. A first side wall upstream of the first side wall and a first side wall downstream of the first side wall; And at least a second side wall extending downstream.
So that the crushing chamber on the upstream side of the outermost edge of the collision surface has a portion having a larger cross-sectional area on the crushing chamber side than the cross-sectional area on the crushing chamber side corresponding to the outermost edge of the second collision surface. 6. An impinging airflow pulverizing means which is enlarged and wherein a tip of the first collision surface is located upstream of a downstream end of the first side wall. Toner. 8. A rotary airflow classifier having a plurality of blades arranged at regular intervals on the same circumference, wherein the rotary airflow classifier has a diameter X of the horizontal rotary rotor of 100.
8. The method according to claim 5, wherein the fine powder discharge pipe has a penetration portion X2 of 5 × 10 ^-3 to 2 × 10 ^-1 m into the horizontal rotary rotor. Toner. 9. The toner having a volume average particle diameter (Dv) of 2.
9. The thickness is 5 to 6.0 [mu] m.
The toner according to any one of the above. 10. The toner according to claim 5, wherein the toner has at least one endothermic peak in a range of 60 to 120 ° C. in differential thermal analysis. 11. The toner according to claim 10, wherein the toner has at least one endothermic peak in a region of 100 ° C. or lower in a differential thermal analysis of the toner. 12. The toner according to claim 1, wherein the toner contains at least one wax component selected from the group consisting of a polyolefin wax, a hydrocarbon wax by a Fischer-Tropsch method, a petroleum wax, and a higher aliphatic alcohol. The toner according to any one of claims 5 to 11, wherein: 13. The toner according to claim 1, wherein the toner contains a wax component having a Mw / Mn in the range of 1.0 to 2.0 in a molecular weight distribution measured by gel permeation chromatography (GPC). Item 13. The toner according to any one of Items 5 to 12. 14. A toner comprising a magnetic powder in the toner, and
The charge amount of the toner with respect to the iron powder carrier is 40 in absolute value.
3. The amount is at least mC / kg.
4. The toner according to any one of 3. 15. An image forming apparatus having at least a latent image holding member and a developing device for visualizing a latent image, wherein the developing device uses at least a surface material of silicone as a toner regulating member, and as a toner carrying member, After melting and kneading a mixture containing at least a binder resin and a colorant as a toner, and cooling the obtained kneaded product, a material having an average surface roughness (Ra) of 1.5 μm or less is used. Powder raw material consisting of a coarsely pulverized product obtained by pulverizing the cooled material by a pulverizing means, having a horizontal rotating rotor,
The fine powder collecting pipe is introduced into a first classifying step using a rotary airflow classifying means in which the fine powder collecting pipe partially enters the horizontal rotary rotor to classify the fine powder into coarse powder and coarse powder. Introduced in the classification process to obtain a classified product for producing toner particles, and the coarse powder classified in the first classification process is introduced into an impinging airflow pulverizing means as a material to be pulverized and finely pulverized. A toner obtained by mixing the finely pulverized material into the powdery raw material, re-introducing the first raw material into the first classifying step, and circulating the toner, wherein the toner has a weight average particle diameter (D ₄ ) Is 3.5 to 6.5 μm
And 200 when the toner is sieved by the suction method.
When the ratio remaining on the mesh is A weight% and the ratio remaining on the 500 mesh is B weight%, A is 0.15%.
An image forming apparatus, wherein a negatively chargeable toner having a BA of 0.02 to 0.3% by weight or less is used. 16. An impingement type air current pulverizing means has an accelerating tube for conveying and accelerating an object to be pulverized by a high-pressure gas and a pulverizing chamber for pulverizing the object to be pulverized. A collision member having a collision surface provided opposite to the opening surface of the outlet of the tube is provided, and a rear end portion of the acceleration tube has a material supply port for supplying the material to be ground into the acceleration tube. The collision surface has a shape consisting of a projecting central portion whose center is protruded and a cone-shaped outer peripheral collision surface provided on the outer periphery thereof, and further the crushed object crushed by the collision member in the crushing chamber. The image forming apparatus according to claim 15, wherein the image forming apparatus is a collision-type airflow pulverizing unit having a side wall for further pulverizing by collision. 17. A high-pressure gas supply nozzle for supplying a high-pressure gas and a high-pressure gas supplied from the high-pressure gas supply nozzle for conveying and accelerating an object to be crushed in the acceleration tube. An accelerating tube, a pulverizing chamber for finely pulverizing the material to be pulverized discharged from the outlet of the accelerating tube, and a pulverized material discharged from the outlet of the accelerating tube provided at a position in the pulverizing chamber facing the outlet of the accelerating tube. A collision type airflow pulverizing means having at least a collision member for pulverizing an object, wherein the collision member has a first collision surface protruding toward the acceleration tube at an apex angle α about a major axis of the acceleration tube. And a second collision surface inclined at an angle β with respect to a perpendicular to the long axis of the accelerating tube toward the downstream side, and the pulverizing chamber has an outermost edge portion of the second collision surface. A first side wall upstream of the first side wall and a downstream side of the first side wall; And at least a second side wall extending downstream.
So that the crushing chamber on the upstream side of the outermost edge of the collision surface has a portion having a larger cross-sectional area on the crushing chamber side than the cross-sectional area on the crushing chamber side corresponding to the outermost edge of the second collision surface. 16. The impingement airflow crushing means, wherein the first collision surface is enlarged and a tip of the first collision surface is located upstream of a downstream end of the first side wall. Image forming apparatus. 18. A rotary airflow classifier having a plurality of blades arranged at regular intervals on the same circumference, wherein the rotary airflow classifier has a diameter X of 10 mm.
18. The method according to claim 15, wherein the fine powder discharge pipe has a penetration portion X2 of 5 × 10 ^-3 to 2 × 10 ^-1 m into the horizontal rotary rotor. The image forming apparatus as described in the above. 19. The toner according to claim 15, wherein the volume average particle diameter (Dv) of the toner is 2.5 to 6.0 μm.
19. The image forming apparatus according to any one of claims 18 to 18. 20. The image forming apparatus according to claim 15, wherein the toner has at least one endothermic peak in a range of 60 to 120 ° C. in differential thermal analysis. 21. The image forming apparatus according to claim 20, wherein a toner having at least one endothermic peak in a temperature range of 100 ° C. or lower in a differential thermal analysis of the toner is used. 22. The toner, wherein the toner contains one or more wax components selected from the group consisting of polyolefin wax, hydrocarbon wax by Fischer-Tropsch method, petroleum wax, and higher aliphatic alcohol. 22. The image forming apparatus according to claim 15, wherein: 23. The toner according to claim 13, wherein the toner contains a wax component having a Mw / Mn in the range of 1.0 to 2.0 in the molecular weight distribution measured by gel permeation chromatography (GPC). Items 15 to 22
The image forming apparatus according to any one of the above. 24. A toner comprising a magnetic powder in the toner, and
The charge amount of the toner with respect to the iron powder carrier is 40 in absolute value.
The image forming apparatus according to any one of claims 15 to 23, wherein mC / kg or more. 25. The image forming apparatus according to claim 15, wherein said image forming apparatus has a cleaning device for removing toner on the latent image holding member. 26. The image forming apparatus according to claim 15, wherein a surface of said toner carrier is coated with a resin coating layer containing conductive fine particles.