JP3397666B2 - Method for producing toner particles - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a toner for developing an electrostatic image. More specifically, the present invention relates to a method for producing toner particles used in a copying machine, a printer or a fax machine, in which a toner image is previously formed on an electrostatic latent image carrier and then transferred onto a transfer material to form an image.

[0002]

2. Description of the Related Art Generally, a toner manufacturing method utilizes a mechanical impact energy after melt-kneading a colorant composed of a dye or a pigment in a binder resin such as a thermoplastic resin and uniformly dispersing the colorant. Various crushers using a high-pressure gas such as a mechanical crusher or jet flow, especially finely crushed by a collision type crusher, and the finely pulverized product obtained is further classified by a classifier to produce a desired particle size. The method of doing so has become the current mainstream from the viewpoints of mass productivity, cost, and the like.

When a toner having an average particle size of 6 μm is to be obtained by using these crushers, the particle size distribution of the crushed toner is from 0.6 μm to 10 including many fine particles.
It has a distribution of about μm, and is used for toner products after removing fine particles by a classification process. However, ultrafine particles with a particle size of 1 μm or less have a strong adhesive force to particles and usually behave in a state of being attached to large particles. It is difficult to completely remove it in the classification process of.

Although many proposals have hitherto been made for suppressing the removal or generation of fine powder of toner, it has hitherto been difficult to accurately measure the particle size distribution of 1.0 μm or less without being affected by noise. Therefore, the particle size is 1μ
Ultrafine particles of toner of m or less were not clearly described. For example, in JP-A-58-42057 and JP-A-6-317931, the range of fine powder to be targeted is 5 μm or less, and ultrafine particles of a toner having a particle diameter of 1 μm or less are not clearly described.

When a large amount of ultrafine particles having a particle size of 1 μm or less is present, there is a large difference between the initial charge amount of the toner and the state after a long run, which causes a phenomenon that the transferability of the toner fluctuates.

If such a phenomenon occurs, it is difficult to uniformly transfer toner images of four colors in the generation of a full-color image, and problems such as color unevenness and color balance are likely to occur.
It is not easy to stably output a high-quality full-color image.

Further, ultrafine particles having a particle diameter of 1 μm or less are easily deposited on the surface of the toner carrier or the surface of the latent image carrier, and when a resin having a low softening point is used, the deposited ultrafine powder forms a film. Since it is easy to do so, it causes an image defect.

Further, in recent years, the printing speed has been increased,
For low-energy fixing, a binder resin of a toner is mainly a resin that softens at a low temperature. Such a resin generally has high pulverizability and tends to generate ultrafine particles having a particle diameter of 1 μm or less. is there. Due to the property of softening at a low temperature, phenomena such as deposition and film formation on the surface of the toner carrier or the surface of the latent image carrier are more likely to occur.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing toner particles which solves the above problems of the prior art.

Specifically, it is an object of the present invention to provide a method for producing toner particles having high transferability from the initial stage to after a long run and having little fluctuation in transferability.

Another object of the present invention is to suppress dirt on the surface of the toner bearing member or the surface of the latent image bearing member, which has high transferability, and has a long life without deteriorating image density or image quality such as fog. Another object of the present invention is to provide a method for producing toner particles capable of stably obtaining a highly durable and high-definition image.

[0012]

The present invention is a toner particle having a binder resin and a colorant, the particle size distribution of which is 0.6 μm to 1.0 μm in terms of the equivalent circle diameter of the toner particle. The percentage of the total is 5.
In the method for producing toner particles, which is less than 0% and has a number average particle diameter of 4 to 10 μm,
(A) A first cylindrical processing chamber, a rotary shaft included in the first cylindrical processing chamber, and a first blade having a plurality of blades on the front surface.
(B) the height of the blade is H _a , the gap between the tip of the blade and the front wall is L _1a, and the longest diameter of the first rotating rotor is and R _1a, blade and when the gap between the side wall of the first cylindrical treating chamber and _{L 2a, H a, L 1a} , R 1a and L _2a is following conditions

[0013]

[Equation 4] (C) The first rotary rotor is rotated by rotating the rotary drive shaft, and the powder supply port provided in the central portion of the front wall of the first cylindrical processing chamber is set. From the above, the toner particles are introduced into the first cylindrical processing chamber together with the gas, and the mechanical impact force is applied to the toner particles while retaining the toner particles in the first cylindrical processing chamber to process the toner particles. The toner particles are discharged from a first powder discharge port provided at the center of the first rear wall of the first cylindrical processing chamber facing the back surface of the first rotating rotor. The present invention relates to a method for producing particles.

According to the present invention, the ratio of the toner particles having a particle size of 1.0 μm or less in the particle size distribution according to the equivalent circle diameter is as follows.
The present invention has been found to have a great influence on electrophotographic characteristics and has led to the present invention.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The method for producing toner particles of the present invention preferably includes means for removing particles having a circle equivalent diameter of 1.0 μm or less of the toner particles. The circle equivalent diameter of the toner particles is 1.0 μm or less. As a means of removing the particles of
It is preferable to perform a process of applying a mechanical impact force.

Equivalent circle diameter of toner particles in the present invention 1.0 μ
The means for removing particles of m or less includes, for example, a normal toner classification step and a method of using a compressed gas at the time of toner supply in the classification step, forcibly dispersing the toner, or a plurality of classification treatments. It is to fix particles having a particle diameter of 1.0 μm or less, which is difficult to be removed by a more precise classification treatment than usual, by a means or the like to the surface of large toner particles by a treatment of applying a mechanical impact force.

In the present invention, in the particle size distribution based on the equivalent circle diameter of the toner particles, the ratio of particles having a particle size of 0.6 μm or more and 1.0 μm or less can be easily achieved to be less than 5.0% of the whole on a number basis. As the above, using the processing device,
A means for removing particles having a circle equivalent diameter of 1.0 μm or less of the toner particles is preferably used.

As the equivalent circle diameter and particle size distribution of the toner particles in the present invention, the values measured using a flow type particle image analyzer FPIA-1000 manufactured by Toa Medical Electronics Co., Ltd. were used.
In this device, the equivalent circle diameter is measured as follows.

As a measuring method, a surfactant (preferably alkylbenzene sulfone) is used as a dispersant in about 50 ml of water (the number of particles in 10 ^-3 cm ³ is 20 or less) from which fine dust has been removed by filtering. Acid salt), and further add about 2 to 20 mg of the measurement sample and perform dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and set the particle concentration of the measurement sample to 4000 to 8000 particles / 10 ^-3 cm ³ . The adjusted sample solution is made to flow in a thin layer in the flow cell, a projection photograph of the flowing particles is taken, the projected area of each particle is measured, and the diameter of a true circle having the same area is measured as the equivalent circle diameter. Then, the particle size distribution of the equivalent circle diameter was determined, and the number-based% of particles having a particle size of 0.6 μm or more and 1.0 μm or less and the number average particle size were calculated.

Conventionally, there were some devices capable of measuring a particle size of 1.0 μm or less, but noise was greatly affected in the region of 1.0 μm or less, and there was a problem in data reproducibility. This device has excellent reproducibility even in a region of 1.0 μm or less, and since information as a particle image is actually obtained at the same time, it is excellent in that particles can be confirmed.

According to the present invention, the proportion of particles having a particle size of 1.0 μm or less in the particle size distribution according to the equivalent circle diameter of toner particles is
The present invention has been found to have a great influence on electrophotographic characteristics and has led to the present invention.

In the particle size distribution based on the equivalent circle diameter of the toner particles, if the proportion of particles having a particle size of 0.6 μm or more and 1.0 μm or less is 5.0% or more of the whole on a number basis, the toner charge amount is the initial value. There is a large difference between the state and the state after the long run, and accordingly, the phenomenon that the transferability of the toner fluctuates occurs. In addition, ultrafine powder easily deposits on the surface of the toner carrier or the toner image carrier, and further, when a resin having a low softening point is used, the deposited ultrafine powder easily forms a film. As a result, stains on the image, problems with the stability of the amount of charge of the toner occur, and many image characteristics such as low image density and fog due to poor transferability are likely to be affected.

Further, the number average particle diameter based on the equivalent circle diameter is 10
If it is more than 4 μm, it is difficult to stably obtain a high-definition image, and if it is less than 4 μm, it is difficult to stably obtain a high-quality image for a long period with the current technology.

Further, in the particles of 3 μm or more of the toner, particles having a circularity a = 0.90 or more are 90% on the number basis.
It is more preferable that the number of particles having the above-mentioned degree and the circularity of 0.98 or more is less than 30%, and when this condition is satisfied, fluctuations in transferability are further reduced.

The circularity in the present invention is used as a simple method for quantitatively expressing the shape of particles,
For example, Toa Medical Electronics Flow Particle Image Analyzer FPIA
The value obtained from the following equation using -1000 is defined as the circularity.

[0026]

[Equation 5] L ₀ : Perimeter of circle having the same projected area as particle image L: Perimeter of particle image

The circularity distribution of the toner particles in the present invention is determined by the flow type particle image analyzer FP manufactured by Toa Medical Electronics Co., Ltd.
The value measured using IA-1000 was used.

The measuring method is the same as the above-mentioned measurement of the equivalent circle diameter, and is calculated by the above formula.

In the present invention, the toner preferably has a volume average diameter of 2.5 to 6.0 μm. When the volume average diameter (Dv) is less than 2.5 μm, the image density tends to decrease, and when it exceeds 6.0 μm, it becomes difficult to form a high quality image.

The above-mentioned particle size distribution can be measured by various methods, but in the present invention, it was measured using the following measuring device.

That is, a Coulter Counter TA-II type or Coulter Multisizer (manufactured by Coulter) is used as a measuring device. As the electrolytic solution, a 1% NaCl aqueous solution is prepared using first grade sodium chloride. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) can be used. As the measuring method, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) as a dispersant is added to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 20 measuring samples are further added.
Add mg. The electrolytic solution in which the sample is suspended is dispersed by an ultrasonic disperser for about 1 to 3 minutes, and the volume and number of the toner are measured by using the 100 μm aperture as an aperture by the above apparatus to calculate the volume distribution and the number distribution. did.
Then, the weight-based volume average particle diameter (Dv) obtained from the volume distribution according to the present invention (the median value of each channel is used as a representative value for each channel) was obtained.

The toner of the present invention is preferably a magnetic toner containing 50 to 200 parts by weight of a magnetic material with respect to 100 parts by weight of a binder resin. When the amount of the magnetic substance is less than 50 parts by weight, particles of 1.0 μm or less generated during pulverization tend to be large, and it becomes difficult to remove particles of 1.0 μm or less.

Examples of the magnetic substance include metal oxides containing elements of iron, cobalt, nickel, copper, magnesium, manganese, aluminum or silicon. Among them, those containing iron oxide as a main component such as ferrosoferric oxide and γ-iron oxide are preferable. From the viewpoint of toner chargeability control, other elements such as a silicon element or an aluminum element may be contained. These magnetic particles, BET specific surface area by nitrogen adsorption method is preferred 2~30m ² / g, especially 3~28m ² /
g, and a magnetic powder having a Mohs hardness of 5 to 7 is preferable.

The shape of the magnetic material is octahedron, hexahedron,
There are spheres, needles, scales, and the like, but octahedrons, hexahedrons, spheres, and irregular shapes having less anisotropy are preferable in order to increase the image density. The average particle size of the magnetic material is
It is preferably 0.05 to 1.0 μm, more preferably 0.
1 to 0.6 μm, more preferably 0.1 to 0.4 μm
It is good that it is m.

The type of the binder resin used in the present invention is, for example, polystyrene, poly-p-chlorostyrene, a homopolymer of styrene such as polyvinyltoluene or a substitution product thereof; styrene-p-chlorostyrene copolymerization. Coalescing,
Styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer Polymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer,
Styrene-based copolymers such as styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer; polyvinyl chloride, phenol resin, natural modified phenol resin, natural resin modified maleic acid resin, acrylic Resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin and petroleum resin can be used. Cross-linked styrenic resins are also preferred binder resins.

Examples of the comonomer for the styrene monomer of the styrene copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate,
Duplex 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 and 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 vinyl ether, for example Vinyl ethyl ether, vinyl ethers such as vinyl isobutyl ether; and the like. These vinyl monomers are used alone or in combination.

As the cross-linking agent, a compound having two or more polymerizable double bonds is mainly used, for example, an aromatic divinyl compound such as divinylbenzene or divinylnaphthalene; for example, ethylene glycol diacrylate. Carboxylic acid esters having two double bonds such as ethylene glycol dimethacrylate and 1,3-butanediol dimethacrylate; divinylaniline, divinyl ether, divinyl sulfide and divinyl sulfone compounds; and 3 or more vinyl groups. The compound having; can be used alone or as a mixture.

Further, it is also preferable to include the following waxes in the toner from the viewpoint of improving the releasability from the fixing member during fixing and 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, etc., where the derivatives are oxides and block copolymers with vinyl monomers. , Including graft modified products. Others, alcohols, fatty acids, acid amides, esters, ketones, hydrogenated castor oil and its derivatives,
Plant waxes, animal waxes, mineral waxes, petrolactam, etc. can also be used.

In the toner of the present invention, it is preferable to use a charge control agent by blending (internal addition) with the toner particles or by mixing (external addition) with the toner particles. The charge control agent makes it possible to control the optimum charge amount according to the development system.
Particularly, in the toner of the present invention, the balance between the particle size distribution and the charge amount can be further stabilized.
As the negative charge control agent for controlling the toner to have negative charge, there are the following substances.

Organic metal complexes and chelate compounds are effective, for example, monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acid metal complexes, and aromatic dicarboxylic acid metal complexes. Others include aromatic hydroxycarboxylic acids, aromatic monocarboxylic acids and aromatic polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

The following substances are available as a positive charge control agent for controlling the toner to have a positive charge property.

For example, modified products of nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and analogs thereof. Onium salts such as phosphonium salts and lake pigments thereof; triphenylmethane dyes and lake pigments thereof (as a laker, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid,
Ferricyanide, ferrocyanide, etc.); metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; diorganotin borates such as dibutyltin borate, dioctyltin borate, dicyclohexyltin borate. There is;

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

The charge control agents described above are preferably used in the form of fine particles, and in this case, the number average particle diameter of these charge control agents is 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 that they are contained in the toner in an amount of 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 colorant used in the present invention is to be black-toned by a chromatic colorant such as carbon black, a magnetic material, a yellow colorant, a magenta colorant and a cyan colorant described below as a black colorant. The combination of is used.

As the yellow colorant, condensed azo compounds, isoindolinone compounds, anthraquinone compounds,
Compounds represented by azo metal complexes, methine compounds and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 6
2, 74, 83, 93, 94, 95, 97, 109, 1
10, 111, 120, 127, 128, 129, 14
7, 168, 174, 176, 180, 181, 191
Is preferably used.

As the magenta colorant, a condensed azo compound, a diketopyrrolopyrrole compound, an anthraquinone, a quinacridone compound, a basic dye lake compound, a naphthol compound, a benzimidazolone compound, a thioindigo compound and a perylene compound are used. Specifically, C.I.
I. Pigment Red 2, 3, 5, 6, 7, 23, 4
8; 2, 48; 3, 48; 4, 57; 1, 81; 1, 1
44, 146, 166, 169, 177, 184, 18
5,202,206,220,221,254 are particularly preferred.

As the cyan colorant, a copper phthalocyanine compound and its derivative, an anthraquinone compound, and a basic dye lake compound can be used. Specifically, C.I. I. Pigment Blue 1, 7, 15, 15: 1, 15: 2, 1
5: 3, 15: 4, 60, 62, 66 and the like can be particularly preferably used.

These colorants can be used alone or in a mixture, and can be used in the form of a solid solution. In the present invention,
The colorant is selected in consideration of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in the toner. These chromatic colorants are 1 to 2 with respect to 100 parts by weight of the binder resin.
0 weight part It is contained in the toner.

As the inorganic fine powder contained in the toner of the present invention, known ones can be used, but silica, alumina, titania or a mixture thereof is used in order to improve charge stability, developability, fluidity and storage stability. It is preferably selected from oxides. Furthermore, silica is more preferable. For example, silica may be either so-called dry silica produced by vapor phase oxidation of silicon halide or alkoxide, or dry silica called fumed silica, and so-called wet silica produced from alkoxide, water glass and the like. However, there are few silanol groups on the surface and inside the fine silica powder, and Na ₂ O, SO
_3/5 ² small dry silica of manufacture residues such as is preferred. In the case of dry silica, it is also possible to obtain a composite fine powder of silica and another metal oxide by using another metal halogen compound such as aluminum chloride or titanium chloride together with a silicon halogen compound in the manufacturing process. They are also included.

The inorganic fine powder used in the present invention is BET.
The specific surface area by measuring nitrogen adsorption in law 30 m ² / g or more, especially given the 50 to 400 m ² / g good results in the range of fine silica powder of 0.1 to 8 weight relative to 100 parts by weight of the toner Parts, preferably 0.5 to 5 parts by weight, more preferably more than 1.0 and up to 3.0 parts by weight.

The inorganic fine powder used in the present invention is
Silicone varnishes, various modified silicone varnishes, silicone oils, various modified silicone oils, silane coupling agents, silane coupling agents having functional groups, other organic silicon compounds, organics for the purpose of hydrophobicization, control of charging properties, etc. It is also possible and preferable to treat with a treating agent such as a titanium compound or in combination with various treating agents.

In order to maintain a high charge amount, achieve a low consumption amount and a high transfer rate, it is more preferable that the inorganic fine powder is treated with at least silicone oil.

In the toner of the present invention, other additives such as Teflon powder, zinc stearate powder, polyvinylidene fluoride powder, lubricant powder; cerium oxide powder, and silicon carbide are used in the toner of the present invention. Powder,
Abrasives such as strontium titanate powders; flowability-imparting agents such as titanium oxide powders and aluminum oxide powders; anti-caking agents; carbon black powders,
It is also possible to use a conductivity-imparting agent such as zinc oxide powder and tin oxide powder; and a developability improving agent such as reverse polarity organic fine particles and reverse polarity inorganic fine particles.

The method for producing toner particles of the present invention will be specifically described with reference to FIGS. 1 to 9.

FIG. 1 shows a system 1 incorporating a processing device for imparting a mechanical impact to the toner particles used in the present invention.
2 shows a partial cross-sectional view of the processing device, FIG.
Shows an enlarged view of a part of a partial sectional view of the processing apparatus.

In the processing apparatus shown in FIG. 2, four cylindrical processing chambers are connected in the cylindrical casing 1, and the first to fourth cylindrical processing chambers 29a to 29d are rotationally driven. Rotating rotors 2a, 2b, 2c and 2d each having eight blades fixed to a shaft 3 with a key 5 (see FIG. 8) are included. The rotary rotors 2a, 2b, 2c and 2d are rotated by the rotary drive shaft 3 in the same direction as the hands of the clock. The rotary drive shaft 3 is rotatably supported by bearings 11 and 12, and has a pulley 4 at the lower end.
The rotation of the electric motor 34 is transmitted by the belt wound around the belt, and the belt rotates at high speed. FIG. 7 shows a perspective view of a rotary drive shaft having four rotary rotors. The rotary rotors 2a, 2b, which are connected to the rotary drive shaft 3 as the rotary drive shaft 3 rotates,
2c and 2d rotate.

The method for producing the toner particles before applying the mechanical impact force of the present invention is such that the binder resin, the colorant, the wax, the charge control agent and the like are uniformly used by using a pressure kneader, an extruder or a media disperser. And then finely pulverized into a desired toner particle size by mechanical pulverization or jet collision, and then classified as necessary to obtain toner particles to be treated. The toner particles to be treated thus obtained are supplied to the fixed amount supply device 1 shown in FIG.
6 through the vibrating feeder 15, the hopper 32 and the powder supply pipe 31, and the powder supply port 30 provided at the center of the front wall 33 of the first cylindrical processing chamber 29a together with the air. Suction blower 2 in one cylindrical processing chamber 29a
Introduced by a suction force of 4. First cylindrical processing chamber 29
The toner particles to be treated introduced into a collide with the side wall 7a of the first cylindrical processing chamber by the air flow from the center direction to the side wall 7a generated by the rotation of the rotating rotor 2a having eight blades, The surface of the toner particles to be treated is treated. The toner particles to be processed are subjected to a surface treatment while convection in the space of the first cylindrical processing chamber, and successively pass through the gap between the side wall 7a and the blade 9a, and the rear surface of the rotating rotor 2a and the first surface.
Rear wall 8a ("guide plate 8a" or "second front wall 3"
3b ”), and is discharged from the first powder discharge port 10a provided in the central portion of the first rear wall 8a. In the processing apparatus of FIG. 2, the first powder discharge port 10
a also serves as the powder supply port of the second cylindrical processing chamber 29b, and the solid particles pass through the first powder discharge port 10a to the second powder discharge port 10a.
Is introduced into the central portion of the cylindrical processing chamber 29b. In the second cylindrical processing chamber 29b, the first cylindrical processing chamber 29a
The toner particles subjected to the surface treatment in (1) are further surface-treated by rotating the rotary rotor 2b having eight blades in the same manner as in the first cylindrical processing chamber 29a. The solid particles surface-treated in the second cylindrical processing chamber 29b are
Further, the surface treatment is performed in the fourth cylindrical treatment chambers 29c and 29d. A sectional view taken along the line AA 'shown in FIG. 2 is shown in FIG. 8, and a sectional view taken along the line BB' is shown in FIG.

The toner particles surface-treated in the fourth cylindrical processing chamber 29d pass through the fourth powder discharge port 10d provided in the central portion of the guide plate 8d and are provided in the tangential direction of the cylindrical casing 1. It is stored in the cyclone 20 through the discharge port 13a of the discharge pipe 13 and the connecting pipe 17. The surface-treated solid particles stored in the cyclone 20 are appropriately taken out from the valve 21. The side wall 7 (7a to 7d) of the processing apparatus I preferably has no unevenness on the surface when performing a surface treatment for satisfying the circularity of the toner particles and the above conditions.

The processing device shown in FIG. 2, the cyclone 20, the bag filter 22 and the suction blower 24 are connected by a communication means such as a pipe. The suction amount by the suction blower 24 is observed by the flow meter 44, and the valves 19a and 1
It is possible to adjust the suction amount with 9b. The fine powder stored in the bag filter 22 is appropriately taken out from the valve 23. The cylindrical casing 1 has a jacket structure,
It is preferable to flow cooling water or hot water or heated steam here as needed to adjust the temperature in the cylindrical processing chamber.

In the first cylindrical processing chamber 29a, the height H _a of the blade 9a installed integrally with the first rotating rotor 2a and the gap L _1a between the tip of the blade 9a and the front wall 33. And the longest diameter R _{1a of} the first rotating rotor 2a,
The gap L _2a between the blade 9a and the side wall 7a of the first cylindrical processing chamber 29a has the following condition.

[0062]

[Equation 6] Are satisfied. L_2a/ R_1aIs preferably 1.5 × 1
0^-3 Through 85.0 × 10^-3 , And more preferably 2.0 ×
10^-3Through 80.0 × 10^-3 Is good. This makes the first
In the cylindrical processing chamber 29a of
Efficient mechanical impact force due to the blade 9a and the side wall 7a
In addition, the toner particles to be processed are received in the first cylindrical processing chamber.
The residence time can be lengthened by convection in 29a.
For uniform and efficient surface treatment of toner particles
It is possible.

For more efficient surface treatment,
H _a is 10.0 to 500.0 mm (more preferably,
20.0 to 400.0 mm) and L _1a is 1 to 3
00 mm (more preferably 5 to 200 mm) and R _1a is 100 to 2000 mm (more preferably
150 to 1000 mm) and L _2a is 1.0 to 1
5.0 mm (more preferably 1.0 to 10.0 mm)
Is good.

Further, the first rotary rotor 2a has 2 to 32 blades (more preferably 4 to 16 blades) for efficient surface treatment of the toner particles to be treated. preferable. FIG. 4 is a plan view of a rotary rotor in which eight blades 9a are integrally formed on the rotary rotor 2a in a radial pattern at substantially equal intervals, and FIG.
A cross-sectional view of the rotating rotor according to C'is shown with diagonal lines,
FIG. 6 shows a perspective view of the rotating rotor. The rotary rotor 2a is
It has a boss portion 2a 'to enhance the connectivity with the rotary drive shaft 3. The rotating rotor 2a lengthens the residence time of the toner particles to be processed, and further, in order to efficiently generate a mechanical impact force on the toner particles to be processed on the side wall, the height H _a of the blade is a half value width of the blade. It is better to be longer than W _a , and more preferably, H _a is 1.1 to 2.0 times longer than W _a .

Internal volume V in the first cylindrical processing chamber 29a_a
Is 1 × 10³ Through 4 × 10⁶ cm³And the blade 9
The area Sa of one sheet of a is 10 to 300 cm²And
The half width Wa of the blade 9a is 10 to 300 mm.
Is preferred to increase the residence time of the toner particles to be treated.
Good

Further, the longest diameter R _{4a of} the first cylindrical processing chamber 29a is preferably 100.5 to 2020 mm, and the longest diameter of the powder supply port 30 is 50 to 5 mm.
00 mm, the longest diameter R _{3a of} the first powder discharge port 10a
Is 50 to 500 mm, and the longest diameter R _2a of the boss portion 2a ′ of the rotary rotor 2a is preferably 30 to 450 mm for efficient surface treatment.

The rear surface of the rotating rotor 2a and the first rear wall 8a
The gap L _3a with respect to can be adjusted by changing the height of the spacer 14, and the size of the gap L _3a and the longest diameter R _3a.
And the maximum diameter R _2a , the number of rotations of the rotary rotor, and the suction amount of the suction blower 24 are adjusted to adjust the degree of processing of the surface of the toner particles to be processed in the first cylindrical processing chamber 29a. .

The gap L _3a is 1 to 30 mm,
It is preferable for prolonging the residence time of the toner particles to be treated.

Furthermore, the longest diameter R _1a of the rotating rotor 2a,
The longest diameter R _{3a of} the first powder discharge port provided on the first rear wall 8a is the following condition.

[0070]

[Equation 7] Is preferably satisfied, and more preferably,
R _1a , R _2a and R _3a are the following conditions

[0071]

[Equation 8] It is good to be satisfied.

The peripheral speed of the outermost edge of the rotating rotor is such that the circularity of solid particles such as toner particles is 90% or more based on the number of 0.90 particles of 3 μm or more, and the circularity is 0. When the surface treatment of 98 or more particles to less than 30% is performed, 10 to 200 m / sec is preferable, and 50 to 150 m / sec is more preferable for efficient treatment. At that time, the rotary rotor is 90 to 40,
The rotation is preferably 000 rpm, more preferably 900 to 20,000 rpm.

In order to efficiently treat the surface of the solid particles, it is preferable that a plurality of cylindrical processing chambers be provided, and it is more preferable that the plurality of cylindrical processing chambers be in communication with each other. The number of cylindrical processing chambers is preferably 2 to 10 chambers (more preferably 3 to 10 chambers), and the surface of solid particles is continuously treated by the blade and the side wall of the rotating rotor in each cylindrical processing chamber. To be done.

In the cylindrical processing chambers after the first cylindrical processing chamber 29a, the same conditions as those in the case of the first cylindrical processing chamber 29a described above are satisfied, so that the surface treatment is performed uniformly. It is preferable for efficiently obtaining the toner particles.

For example, the second cylindrical processing chamber 29b shown in FIGS. 2 and 3 communicates with the first cylindrical processing chamber 29a through the powder discharge port 10a which the first rear wall 8a has in the central portion. Therefore, the toner particles subjected to the surface treatment in the first cylindrical processing chamber 29a are introduced from the powder discharge port 10a into the central portion of the second cylindrical processing chamber 29b and further processed.

In the second cylindrical processing chamber 29b, the height _Hb of the blade 9b integrally installed on the second rotating rotor 2b, the tip of the blade 9b and the first cylindrical processing chamber 29a. The rear wall of the second cylindrical processing chamber 2
The gap L _1b with the guide plate 8a which is also the front wall of 9b, the longest diameter R _{1b of} the second rotating rotor 2b, and the gap L _2b with the blade 9b and the side wall 7b of the second cylindrical processing chamber 29b. ,
The following conditions

[0077]

[Equation 9] Are satisfied. L_2b/ R_1bIs preferably 1.5 × 1
0^-3 Through 85.0 × 10^-3 , And more preferably 2.0 × 1
0^-3Through 80.0 × 10^-3 Is good. This allows the second
Even in the cylindrical processing chamber 29b, the toner particles are not removed by the blade.
9b and the side wall 7b efficiently receive a mechanical impact force,
Further, the toner particles convection in the second cylindrical processing chamber 29b.
By doing so, the residence time can be lengthened, so uniform and efficient
It is possible to perform good surface treatments on the toner particles.

For more efficient surface treatment,
_Hb is 10.0 to 500.0 mm (more preferably,
20.0 to 400.0 mm) and L _1b is 1 to 3
00 mm (more preferably 5 to 200 mm) and R _1b is 100 to 2000 mm (more preferably
150 to 1000 mm) and L _2b is 1.0 to 1
5.0 mm (more preferably 1.0 to 10.0 mm)
Is good.

The second rotary rotor 2b preferably has 2 to 32 blades (more preferably 4 to 16 blades) for efficient surface treatment of toner particles. The rotating rotor 2b lengthens the residence time of the toner particles, and further, in order to efficiently generate a mechanical impact force on the toner particles on the side wall, the height _{Hb of the} blade is
It is preferable that the half width of the blade be longer than W _b , and more preferable that H _b be 1.1 to 2.0 times longer than W _b .

Internal volume V in the second cylindrical processing chamber 29b_b
Is 1 × 10³ Through 4 × 10⁶ cm³And the blade 9
Area S of one sheet of b_bIs 10 to 300 cm²And blur
Half-width W of code 9b_bIs 10 to 300 mm
It is preferable for prolonging the residence time of the toner particles.

Further, the second cylindrical processing chamber 29b preferably has a longest diameter R _4b of 100.5 to 2020 mm, and further, the longest diameter of the powder discharge port 10a is 50 to 500 m. Longest diameter R _3b of powder discharge port 10b
Is 50 to 500 mm, and the longest diameter R _2b of the boss portion 2b ′ of the rotary rotor 2b is preferably 30 to 450 mm for efficient surface treatment.

The rear surface of the rotating rotor 2b and the second rear wall 8b.
The gap L _3b can be adjusted by changing the height of the spacer, and the gap L _3b is 1.0 to 30.0 mm.
Is preferable in order to prolong the residence time of the toner particles.

Further, the longest diameter R _1b of the rotating rotor 2b,
The longest diameter R _{3b of} the second powder discharging port provided on the second rear wall 8b is the following condition.

[0084]

[Equation 10] Is preferably satisfied, and more preferably,
R _1b , R _2b and R _3b are the following conditions

[0085]

[Equation 11] It is good to be satisfied.

When the process of applying a mechanical impact force is carried out after the step of finely pulverizing the toner or after further the step of classification, the effect of preventing the transfer efficiency from lowering is further enhanced, which is particularly preferable.

Either the classification or the surface treatment may be performed first. In the classification step, it is preferable to use a multi-division classifier because it enables highly accurate classification of the toner and can efficiently and stably generate the toner.

Further, it is preferable to carry out classification and surface treatment to obtain toner particles, and to add and mix inorganic fine powder and the like if necessary.

[0089]

【Example】   [Example 1] ・ Styrene-butyl acrylate-butyl maleate half ester copolymer                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.24 μm) 100 parts by weight ・ Iron complex of monoazo dye (negative charge control agent) 2 parts by weight ・ Low molecular weight polyethylene (differential thermal analysis endothermic peak 104 ° C) 4 parts by weight

The above materials were mixed in a blender, and 130
The kneaded material was melt-kneaded with a twin-screw extruder heated to ℃, and the kneaded material cooled was roughly crushed by a hammer mill, and the coarsely crushed material was finely crushed by a crushing means having an airflow classifier and a collision type airflow crusher. The finely pulverized product obtained was compressed with a compressed air of 2.0 kg / cm ² in a multi-division classifier using the Coanda effect, which has a forced powder disperser using compressed air in the powder supply section. Supply while forcibly dispersing, strictly classify, number average circle equivalent diameter 5.8 μm, circle equivalent diameter 0.6 μm or more 1.0
The ratio of particles having a size of μm or less is 5.2 based on the number.
% Magnetic toner particles were obtained.

Further, the surface of the magnetic toner particles was treated with the magnetic toner by using the apparatus system shown in FIG. 1 having the treatment apparatus shown in FIGS. 2 and 3 set as shown in Tables 1 and 2.

The magnetic toner particles introduced into the vibration feeder 15 were introduced through the hopper 32 at a rate of 20 kg / hr. The rotation speed of the rotating rotor was 8000 rpm, the peripheral speed of the outermost edge of the rotating rotor was 101 m / sec, and the internal temperature of the processing apparatus I was 47 ° C.

At the time of introducing the magnetic toner particles, the blower 24 was operated to draw in an air flow which was slightly larger than the air flow rate generated by the rotation of the blades 9a to 9d, and was collected by the cyclone 20. The introduced magnetic toner particles were surface-treated and collected in a time of 20 seconds or less.

The number average circle-equivalent diameter of the obtained magnetic toner is 6.4 μm, the proportion of particles having a circle-equivalent diameter of 0.6 μm or more and 1.0 μm or less is 0.6% of the whole on a number basis, and the circularity a = The number of particles of 0.90 or more was 95.2% on the number basis, and the number of particles of circularity a = 0.98 or more was 25.0% on the number basis.

To the obtained magnetic toner particles, 1.2 wt% of dry silica having a primary particle size of 12 nm, which was hydrophobized with silicone oil and hexamethyldisilazane, was added to the obtained magnetic toner particles to prepare a mixed group. And mixed to obtain Toner 1.

Laser beam printer 5 manufactured by Hewlett-Packard Co. with transfer bias set to 10 μA.
Using Toner 1 as Si, the transferability fluctuation was evaluated in the environment of 23 ° C. and 65% RH at the initial stage and after 10,000 sheets of running. A 75 g / m ² plain paper was used as the transfer paper. At this time, the transfer efficiency from the photoconductor to the paper was 92.1% at the initial stage, and 91.8% after 10,000 sheets were run, showing a high transfer efficiency with almost no change, and the image quality such as image density and fog was initially low. It was stable at a good level from the end of 10,000 sheets.

The transferability is based on the Macbeth density of what is obtained by taping off the transfer residual toner and the toner before transfer on the solid black photoconductor with Mylar tape and pasting it on the paper.
It was evaluated by the value calculated from the value obtained by subtracting the Macbeth density of the tape only.

Example 2 The surface of the magnetic toner particles was the same as in Example 1 except that the amount of untreated magnetic toner particles introduced into the hopper 32 was set to 15 kg / hr and the rotational speed of the rotating rotor was set to 9000 rpm. Was processed.

The number average circle-equivalent diameter of the obtained magnetic toner is 6.2 μm, the proportion of particles having a circle-equivalent diameter of 0.6 μm or more and 1.0 μm or less is 0.5% based on the number, and the circularity a = The number of particles of 0.90 or more was 96.2% on the number basis, and the number of particles of circularity a = 0.98 or more was 26.2% on the number basis.

As a result of performing the evaluation in the same manner as in Example 1, the transfer efficiency from the photoconductor to the paper at this time was 92.3% at the initial stage,
It showed high transfer efficiency with almost no fluctuations of 91.8% after 10,000 sheets, and the image quality such as image density and fog was stable at a good level from the initial stage to 10,000 sheets.

Example 3 The surface of magnetic toner particles was treated using the apparatus system shown in FIG. 1 having the treatment apparatus shown in FIGS. 2 and 3 set as shown in Tables 1 and 2.

The surface of the magnetic toner particles was treated in the same manner as in Example 1 except that the amount of untreated magnetic toner particles introduced into the hopper 32 was 80 kg / hr and the rotation speed of the rotating rotor was 4200 rpm.

The number average circle-equivalent diameter of the obtained magnetic toner is 6.2 μm, the proportion of particles having a circle-equivalent diameter of 0.6 μm or more and 1.0 μm or less is 0.4% based on the number, and the circularity a = The number of particles of 0.90 or more was 96.8% on the number basis, and the number of grains of circularity a = 0.98 or more was 26.8% on the number basis.

As a result of evaluation in the same manner as in Example 1, the transfer efficiency from the photoconductor to the paper at this time was 92.9% at the initial stage,
It showed high transfer efficiency with almost no change of 91.9% after 10,000 sheets, and the image quality such as image density and fog was stable at a good level from the initial stage to 10,000 sheets.

Comparative Example 1 A magnetic toner was obtained in the same manner as in Example 1 except that the amount of the magnetic material in Example 1 was set to 40 parts by weight and the surface treatment by mechanical impact force was not performed after the classification step.

The number average circle-equivalent diameter of the obtained magnetic toner is 5.7 μm, the proportion of particles having a circle-equivalent diameter of 0.6 μm or more and 1.0 μm or less is 6.5% of the whole on a number basis, and the circularity a = Particles of 0.90 or more were 86.8% on the number basis, and particles of circularity a = 0.98 or more were 11.8% on the number basis.

As a result of performing evaluation in the same manner as in Example 1, the transfer efficiency from the photoconductor to the paper at this time was 90.5% at the initial stage,
After running 10,000 sheets, there was a large change of 80.5%, and the image density also decreased.

[0108]

[Table 1]

[0109]

[Table 2]

[0110]

According to the method for producing toner particles of the present invention, in the particle size distribution based on the equivalent circle diameter of the toner particles, the ratio of the particles having a particle size of 0.6 μm or more and 1.0 μm or less to the total number is 5 on a number basis. Less than 0.0%, number average particle size 4
It is possible to efficiently and easily produce a toner having a particle size of 10 μm, and the toner has a high transferability from the initial stage to after a long run, and there is little fluctuation in the transferability, and a high-definition image can be obtained. You can

[Brief description of drawings]

FIG. 1 is a schematic external view of an apparatus system having an example of a vertical surface treatment apparatus of the present invention.

FIG. 2 is a schematic sectional view of a vertical surface treatment apparatus of the present invention.

FIG. 3 is a partial schematic enlarged cross-sectional view of the vertical surface treatment apparatus of the present invention.

FIG. 4 is a plan view of a rotating rotor.

5 is a cross-sectional view of the rotary rotor taken along the plane CC 'in FIG.

FIG. 6 is a perspective view of a rotating rotor.

FIG. 7 is a perspective view of a rotating shaft provided with a rotating rotor.

8 is a cross-sectional view taken along the plane A-A 'in FIG.

9 is a cross-sectional view taken along the plane B-B ′ in FIG.

[Explanation of symbols]

1 Cylindrical casing 2a, 2b, 2c, 2d rotating rotor 3 rotation drive shaft 4 pulley 5 keys 6 nuts 7a side wall 8a Rear wall (guide plate) 9a, 9b, 9c, 9d blades 10a, 10b, 10c, 10d Powder discharge port 15 Vibration feeder 16 Fixed amount supply device 19a, 19b valve 20 cyclone 21,23,26 valve 22 Bug filter 24 blowers 29a, 29b, 29c, 29d Cylindrical surface treatment chamber 30 powder supply port 31 powder supply pipe 32 hopper 33 front wall 34 Electric motor

Front page continuation (72) Inventor Hitoshi Kanda 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) Reference JP-A 63-244051 (JP, A) JP-A 62-209542 ( JP, A) JP 61-61627 (JP, A) JP 53-6040 (JP, A) JP 53-5633 (JP, A) JP 9-288373 (JP, A) JP JP-A-9-197714 (JP, A) JP-A-9-197712 (JP, A) JP-A-9-160283 (JP, A) JP-A-8-278659 (JP, A) JP-A-7-261450 (JP , A) JP-A-3-77963 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 9/08

Claims (12)

(57) [Claims] 1. A toner particle having a binder resin and a colorant, wherein the proportion of particles having a particle diameter of 0.6 μm to 1.0 μm in the particle size distribution according to the equivalent circle diameter of the toner particle is entirely on a number basis. Of the toner particles having a number average particle diameter of 4 to 10 μm, the method comprising: (a) a first cylindrical processing chamber and a first cylindrical processing chamber; A rotating shaft to be contained and a first blade having a plurality of blades on the front surface
(B) the blade height is H _a , the gap between the blade tip and the front wall is L _1a, and the longest diameter of the first rotating rotor is Let R _1a and the gap between the blade and the side wall of the first cylindrical processing chamber be L _2a , then H _a , L _1a , R _1a and L _2a satisfy the following condition: (C) The first rotary rotor is rotated by rotating the rotary drive shaft, and the powder supply port provided in the central portion of the front wall of the first cylindrical processing chamber. From the above, the toner particles are introduced into the first cylindrical processing chamber together with the gas, and while the toner particles are retained in the first cylindrical processing chamber, a mechanical impact force is applied to the toner particles to process the toner particles, The toner particles are discharged from a first powder discharge port provided at the center of the first rear wall of the first cylindrical processing chamber facing the back surface of the first rotating rotor. Method for producing particles. 2. The method for producing toner particles according to claim 1, wherein the toner particles are subjected to mechanical impact when passing through the gap between the blade and the side wall of the first cylindrical processing chamber. 3. The method for producing toner particles according to claim 1, wherein the toner particles are produced through a kneading step, a pulverizing step and a classifying step before the treatment. 4. The method for producing toner particles according to claim 1, wherein particles having a circle equivalent diameter of 1.0 μm or less are removed by applying a mechanical impact force. 5. The toner particles according to claim 1, wherein the toner particles are magnetic toner particles containing 50 to 200 parts by weight of a magnetic material with respect to 100 parts by weight of a binder resin. Manufacturing method. 6. A toner particle having a particle size of 3 μm or more, the content of particles having a circularity a = 0.90 or more calculated by the following formula is 90% or more on a number basis, and a circularity of 0.98. The method for producing toner particles according to claim 1, wherein the toner particles are treated so that the content of the particles is less than 30%. [Equation 2] L ₀ : Perimeter of circle having the same projected area as particle image L: Perimeter of particle image 7. The method according to claim 1, wherein H _a is 10.0 to 500.0 mm, L _1a is 1 to 300 mm, R _1a is 100 to 2000 mm, and L _2a is 0.5 to 200 mm. 7. The method for producing toner particles according to any one of 6 above. 8. A cylindrical treatment chamber, a rotary drive shaft and the claims plurality of cylindrical processing chamber for a plurality of blades and a rotating rotor having the front are contained respectively are provided to communicate with 1 to 7 5. The method for producing toner particles according to any one of 1. 9. The powder discharge port of the first cylindrical processing chamber is the powder supply port of the second cylindrical processing chamber for introducing the solid particles processed in the first cylindrical processing chamber. There, the toner particles treated in the first cylindrical treating chamber are further production of the toner particles according to any one of the second cylindrical processing claims 1 to 8 indoors are surface treated by mechanical impact force Method. 10. A method for producing toner particles according to claim 8 or 9 cylindrical processing chamber is provided 2 to 10 rooms. 11. The rotary drive shaft which is contained in a plurality of cylindrical processing chamber, the manufacturing method of the toner particles according to any one of claims 8 to 10 which is a common rotary drive shaft. 12. A second cylindrical processing chamber having a second cylindrical processing chamber and a plurality of blades contained in the second cylindrical processing chamber on a front surface thereof.
In the rotating rotor of No. 1, the height of the blade is H _b , the gap between the tip of the blade and the front wall is L _1b , the longest diameter of the second rotating rotor is R _1b , and the blade and the second cylindrical treatment are The space between the chamber and the side wall is L
_2b , H _b , L _1b , R _1b and L _2b satisfy the following condition: The method for producing toner particles according to any one of claims 1 to 11 , which satisfies the above condition.