JPH0792730A - Manufacture of toner - Google Patents

Abstract

PURPOSE:To provide a manufacture method for toner which is used for electrophotography or the like and has excellent fluidity and developing properties. CONSTITUTION:The toner manufacturing method has a process (a) where a toner containing one or more kinds of externally adding agents is vibrated using a sieve having a fixed mech and made to freely drop for obtaining the toner having a fixed g rain size, and a process (b) where the toner containing one or more kinds of externally adding agents is brushed using a sieve having a fixed mesh and forcedly passed through the sieve for obtaining the toner having a fixing grain size. The toner obtained by the process (a) and the toner obtained by the process (b) are mixed at the mixing ratio of 95:5 to 5:95.

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 used for electrophotography and more particularly to a method for producing a toner having excellent fluidity and developability.

[0002]

2. Description of the Related Art In an electrophotographic apparatus or an electrostatic recording apparatus, a toner has been conventionally used for visualizing an electrostatic latent image formed on an electrostatic image carrier made of a photoconductor or a dielectric. A two-component developing method using a two-component toner composed of a carrier and a carrier, a one-component developing method using a toner having a carrier function, and the like are widely used.

Examples of these electrophotographic methods include US Pat. No. 2,297,691 and JP-B-42-23910.
U.S. Pat. No. 3,666,363, U.S. Pat. No. 4,324,748, U.S. Pat. No. 4,071,361, U.S. Pat. No. 3,909,258, U.S. Pat. 4,121,931 and 2,895,84
No. 7, No. 3,152,012, Japanese Patent Publication No. 41-9475, No. 45-2877, No. 5
A large number of methods disclosed in Japanese Patent Laid-Open No. 4-3624 are known.

In these electrophotographic methods, in general, an electrostatic latent image is formed on a photoreceptor using a photoconductive substance by various means, and then this latent image is developed with a toner, and if necessary, it is developed. After the toner image is transferred onto a transfer material such as paper, it is fixed by heat, pressure or solvent vapor to obtain a copy.

In the toner used in such an electrophotographic developing method, a colorant and other additives (external additives) are generally mixed in a thermoplastic resin and uniformly dispersed, and then a solidified product is finely divided. It can be obtained by pulverizing and classifying to obtain desired colored fine particles. A method of adding hydrophobic silica as an external additive to the colored fine particles in order to prevent the filming of the toner on the photosensitive member and to improve the fluidity is known. No. 16219, for example.

However, this type of toner has some problems as described below. (1) The amount of charge due to frictional charging becomes insufficient. That is, when the toner for replenishment is additionally charged into the toner and the toner carrier (carrier) that have been mixed and stirred in advance, a difference in friction charging time occurs, so that the electrostatic latent image is added to the additionally charged toner. It is not possible to obtain the amount of electrified charge necessary to visualize the image.

(2) Even if a desired amount of charge is obtained by triboelectrification, the triboelectrification characteristics thereof are adversely affected by changes in temperature and humidity. (3) The surface of the toner carrier is deteriorated by repeated development by continuous use, and as a result, the triboelectric charging characteristics of the toner are adversely affected.

(4) It is necessary to control the triboelectric charge amount with respect to the surface area of the toner within a certain range, but it is difficult to adjust it, and it is difficult to produce a toner having stable performance with good reproducibility.

In order to solve these problems, various methods exemplified below have been proposed.
Japanese Patent Laid-Open No. 5072 discloses a method for producing a toner in which an external additive is added to toner particles and then heat treatment is performed.
In this method, the toner is left in a constant temperature bath,
The toner manufactured in this manner has a problem that the fluidity is deteriorated.

Japanese Unexamined Patent Publication (Kokai) No. 63-139366 discloses a method for producing an electrophotographic toner in which filming on the photosensitive member is prevented by removing fine silicic acid powder not adhering to the toner. When the silica fine powder that has not adhered to the toner is completely removed, there is a problem that the fluidity deteriorates.

Japanese Unexamined Patent Publication (Kokai) No. 60-115945 discloses a non-magnetic one-component developer in which hydrophobic silica is adhered to the toner surface in a partially aggregated state, which is disclosed in this publication. In the manufacturing method described above, the mixing of the hydrophobic silica is insufficient and the apparent fluidity is improved, but the desired developing characteristics cannot be obtained.

Japanese Unexamined Patent Publication (Kokai) No. 3-170948 discloses a toner for developing an electrostatic latent image containing silica particles composed of a secondary aggregate of wet silica and having an average particle size of 1 μm or more. The toner containing the toner can prevent filming on the photoconductor due to silica, but the toner itself cannot maintain the state of particles, and the particles scatter to contaminate the inside of the electrophotographic apparatus.

[0013]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems and has a good and moderate fluidity and does not change the triboelectrification characteristics even during repeated development by continuous use. In addition, it does not cause filming on the photoreceptor, fogging on the transfer paper, and scattering of toner inside the device, and faithfully visualizes the electrostatic latent image in high quality,
An object of the present invention is to provide a method for producing a toner that gives a clear image.

[0014]

In order to obtain a toner having a specific particle size containing one or more kinds of external additives, the present inventors have used a sieve to vibrate the toner and let it fall freely, and The inventors have found that the use of a mixture of a brush and toner forcibly passing the toner at an appropriate ratio makes it possible to achieve both contradictory properties such as fluidity and developability, and completed the present invention. Came to do.

That is, according to the present invention, (a) a toner containing one or more kinds of external additives is used with a sieve having a predetermined mesh, the sieve is vibrated, and the toner is allowed to fall freely to obtain a toner having a predetermined particle size. And (b) a step of using a sieve of a predetermined mesh with a toner containing one or more kinds of external additives, brushing the sieve to forcefully pass the sieve to obtain a toner having a predetermined particle size, A toner comprising the toner obtained in the step (a) and the toner obtained in the step (b) are mixed at a mixing ratio of 95: 5 to 5:95. A manufacturing method is provided.

When the mixing ratio of the toner obtained in the step (a) and the toner obtained in the step (b) is larger than 95, the fluidity of the finally obtained toner is satisfactory. If the mixing ratio is less than 5, the charge amount of the toner finally obtained may be excessively increased, which is not preferable.

The toner obtained in the above step (a),
A more preferable mixing ratio with the toner obtained in the step (b) is in the range of 75:25 to 25:75. In the present invention, the toner is manufactured, for example, as follows using a binder resin, a colorant and an external additive.

First, 100 parts by weight of the binder resin and 1 to 10 parts by weight of the colorant are mixed and dispersed by using a ball mill, a V type mixer or the like. The mixture is then pressure kneaded,
The mixture is heated, melted and kneaded by using a roll or the like. The obtained kneaded product is roughly crushed using a hammer mill, a jet mill or the like. After pulverizing with a jet mill etc.,
Classify to a desired particle size by a wind force classification method, etc., add an external additive to this, and mix this with a high-speed flow type mixer,
Finally, as described above, the two types of sieves are used to classify the particles to have a desired particle size, and these are mixed at an appropriate ratio as described above to obtain a desired toner.

In the present invention, as the means for mixing, kneading and dispersing the toner used before the final classification by using the two types of sieves as described above, in addition to the above-mentioned examples, a high speed dissolver and a ball are used. It is possible to use a wet dispersion method such as a rumill or a melt kneading method such as an internal mixer or a screw type extruder, and as a mixing means, a ball mill, a V type mixer, a Forberg, A Henschel mixer or the like can be used. Further, as means for coarsely pulverizing the mixture, for example, a cutter mill, a roll
A ramill, ball mill, etc. can be used. Further, as a means for finely pulverizing the coarsely pulverized product, a high speed rotary pulverizer or the like can be used. Further, as a means for classifying the finely pulverized product, an airflow classifier or the like can be used.

The amount of the external additive added before the toner is sieved is preferably 0.1 to 5.0 parts by weight, more preferably 0.3 to 5.0 parts by weight, based on 100 parts by weight of the toner particles.
0.5 parts by weight.

As external additives, silica fine particles, metal oxide fine particles, cleaning aids and the like are used. As the silica fine particles, silicon dioxide, aluminum silicate, sodium silicate, potassium silicate, zinc silicate,
Examples include magnesium silicate. Examples of the metal oxide fine particles include zinc oxide, titanium oxide, aluminum oxide, zirconium oxide, strontium titanate, and barium titanate. Examples of the cleaning aid include resin fine powder such as polymethylmethacrylate, polyvinylidene fluoride and polytetrafluoroethylene. These external additives may be those subjected to surface treatment such as hydrophobization.

As a means for mixing the external additive, a known mixing device can be used, but it is preferable to use, for example, a high speed fluid type mixing device. As a high-speed fluid type mixing device,
For example, a Henschel mixer, a super mixer, a micro speed mixer and the like can be mentioned.

The binder resin used in the present invention is
Conventionally, a copolymer of styrene and a substitute thereof, which has been used as a binder resin for toner, or an acrylic resin can be used.

Examples of the copolymer of styrene and its substitution product include polystyrene homopolymer, hydrogenated styrene resin, styrene-isobutylene copolymer,
Styrene-butadiene copolymer, acrylonitrile-butadiene-styrene terpolymer, acrylonitrile-
Styrene-acrylic ester terpolymer, styrene-acrylonitrile copolymer, acrylonitrile-acrylic rubber-styrene terpolymer, acrylonitrile-
Chlorinated polystyrene-styrene terpolymer, acrylonitrile-EVA-styrene terpolymer, styrene-
Examples thereof include p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene rubber, styrene-maleic acid ester copolymer, styrene-isobutylene copolymer, styrene-maleic anhydride copolymer and the like.

As the acrylic resin, for example,
Polyacrylate, polymethylmethacrylate, polyethylmethacrylate, poly-n-butylmethacrylate
And polyglycidyl methacrylate, polyfluorinated acrylate, styrene-methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-ethyl acrylate copolymer and the like.

Other binder resins include polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyurethane, polyamide, epoxy resin, phenol resin, urea resin, polyvinyl butyral, polyacrylic acid resin. , Rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax and the like can be used alone or in combination.

As the colorant used in the present invention, carbon black or organic or inorganic pigments or dyes are used. Carbon black includes acetylene black, furnace black, thermal black, channel black, and Ketjen black, although there are no special restrictions. Examples of facial dyes include Faste yellow-G, Benzidine yellow, Indo fast orange, Irgadine red, Carmine FB, Permanentbold-FRR, Pigment orange R, Lisor red 2G, Lake red. C, Rhodamin FB, Rhodamin B
Lake, phthalocyanine blue, pigment bull, brilliant green B, phthalocyanine green, quinacridone, etc. are used. These facial dyes can be used alone or in combination.

In the present invention, waxes for improving anti-offset characteristics, charge control agents for controlling the amount of triboelectric charges, and the like may be blended, if necessary. Examples of the charge control agent include metal chelate of alkylsalicylic acid, chlorinated polyester, polyester with excess acid groups, chlorinated polyolefin, metal salt of fatty acid, negative polarity control agent such as fatty acid soap, dimethylaminoethyl methacrylate-styrene. Examples of positive polarity control agents such as copolymers, fluorine-based surfactants and hydrophobic silica.

The toner thus obtained can be applied to all known developing methods. For example, cascade method, magnetic brush method, two-component developing method such as microtoning method, conductive one-component developing method, insulating one-component developing method, jumping developing method, etc. Method, a fur brush method, a non-magnetic one-component developing method in which the toner is conveyed to a developing unit by being electrostatically held on a toner carrier and developed.

[0030]

In the toner manufacturing method of the present invention, a toner having good fluidity obtained by vibrating the sieve and free-falling the toner is obtained from the toner obtained by forcibly passing the toner by brushing the sieve. Since the toners are mixed in an appropriate ratio, the obtained toner has a good moderate fluidity and stable triboelectric charging characteristics. By using such toner,
It is possible to obtain a clear image that does not depend on the environment and has no toner fog or toner scattering. Such toner characteristics are retained even during repeated development by continuous use, and the quality of the copied image does not deteriorate.

[0031]

EXAMPLES The present invention will now be described in more detail with reference to examples. First, an example of an image forming apparatus to which the toner of the present invention is applied will be described with reference to FIG.

The copying machine shown in FIG. 3 is constructed as follows. That is, a drum-shaped photosensitive member 103 is provided as an image carrier rotatably in the direction of arrow a in the center of the copying machine main body 101 (hereinafter referred to as the main body 101). The photoconductor 103 has a photoconductive layer on its surface.
The following devices are fixed around the photoconductor 103 along the rotation direction thereof.

That is, the charging charger 105 that uniformly charges the surface of the photoconductor 103, and this charging charger.
A slit glass 107 for slit exposure of a document image as a light source is provided on the charged photoconductor 103 above the photoconductor 103 on the downstream side in the rotation direction of the photoconductor 103. Further, on the downstream side of the slit glass 107, a developing device 109 for developing a toner by attaching a toner to the electrostatic latent image on the photoconductor 103.
In the developing device 109, a toner 110 mixed with a carrier as a developer is housed.

Further, in the developing device 109, a stirring roller 20 for stirring and frictionally charging the developer by the rotation of the roller.
1, and a supply roller 202 for supplying the developer stirred by the stirring roller 201 to the magnet roller 203 described below.
Is provided. Further, in the developing device 109, a magnet roller 203, in which S poles and N poles are alternately arranged along the rotation direction of the roller, is rotated in the direction of arrow l in the drawing in a state of approaching the photoconductor 103. It is possible.

A transfer device 111 and a peeling device 113 are provided on the downstream side of the developing device 109. The transfer device 111 is a device that transfers the toner image formed by the developing device 109 onto a copy sheet (hereinafter referred to as a sheet), and the peeling device 113 uses the transfer device 111 to transfer the toner image to the photoconductor 10.
3 is a device for peeling the paper adsorbed on the surface from the surface of the photoconductor 103.

Downstream of the peeling device, among the toners 110 attached to the surface of the photoconductor 103, the toners remaining on the photoconductor 103 after being transferred by the transfer device 111.
A cleaning device 115 for removing 110 is provided. Cleaning device 115 and charging charger 10
A static eliminator 117 for lowering the potential of the photoconductor 103 is fixedly installed between 5 and 5.

Further, the main body 101 has an original glass 119 on which an original is placed and an optical system 121 for irradiating the original on the original glass 119 with light and guiding the reflected light onto the surface of the photoconductor 103. . The optical system 121 includes a lamp 123 as a light source and mirrors 124, 125, 127, 129, 131, 13 for reflecting light emitted from the light source.
3 and a lens unit 135 for forming an image of reflected light
have.

The lamp 123 and the mirror-124 are constructed so as to be movable under the original glass 119, and in order to always keep the optical path length constant, the mirror-125 and the mirror-127 are half of the lamp 123. It is configured to move at speed. The reflected light from the mirror-133 is configured to pass through the slit glass 107 and be guided to the surface of the photoconductor 103.

In the middle of the right side of the main body 101, a manual feed tray 141 for accommodating sheets is detachably provided, and in the main body 1, the paper stored in the manual feed tray 141 is located above the tip of the manual feed tray 141. A pickup roller 143 for pulling out is provided.

On the left side of the main body 101, a paper discharge tray 171 for discharging the copied paper is provided.
Between the manual feed tray 141 and the paper discharge tray 171,
A sheet conveying path, that is, a conveying path 142 is formed, and the conveying path 142 is shown by a dotted line in FIG.

Two pairs of rollers, a first roller pair and a second roller pair, are attached to the main body 101 upstream of the conveying path 142. The first roller pair is composed of two rollers, a paper feeding roller 145 and a separating roller 147, which are adjacent to the manual feed tray 141. The paper feed roller 145 is a roller that can rotate in the direction of the arrow b in the figure, and is a roller for sending the paper pulled out by the pickup roller 143 to the second roller pair by the rotation of the roller. is there.

The separating roller 147 is provided below the paper feeding roller 145 so as to be in contact therewith, and when the number of sheets sent from the pickup roller 143 is two or more, the paper feeding roller 147 is provided. The extra paper is pulled back to the manual feed tray 141 by rotating in the opposite direction of the rotation direction of the la 145. Separating roller 147
When the number of sheets sent from the pickup roller 143 is one, the sheet feeding roller 145 is rotated by the rotation. The second roller pair is a resist roller 149 composed of an upper roller and a lower roller. Registrar
The roller 149 aligns the paper by hitting the leading edge of the paper sent from the paper feed roller 145, and then the paper is placed on the photoconductor 103 between the photoconductor 103 and the transfer device 111. Send it so that it overlaps with the toner image.

The transfer device 1 is provided in the middle of the transport path 142.
11 and a peeling device 113 are arranged, and a belt-shaped belt for transporting paper, that is, a transport belt 15 is provided at the tip thereof.
1 is provided. Further, on the downstream side of the transport path 142, heating and pressurizing the toner 110, the toner 11 is discharged.
A fixing device 153 for fixing 0 on paper is installed. The fixing device 153 includes a heat roller 157 and a pressure roller 1 which are rotatable in directions c and d in the drawing.
Have 59. The heat roller 157 has a built-in heat lamp 155, which is a heating body, and is partially pressure-bonded to the pressure roller 159. The surface of the heat roller 157 is made of a metal member having good thermal conductivity, and the surface of the pressure roller 159 is made of an elastic rubber member so that it can be easily pressure-bonded to the heat roller 157. There is.

Further, downstream of the transport path 142, a paper discharge roller for discharging the paper on which the copying machine is mounted to the paper discharge tray 171.
La 161 is provided. The copying process by the copying machine described above is as follows.

First, the surface of the photoconductor 103 is uniformly charged by the corona discharge of the charging charger 105. Next, the lamp 123 in the optical system 121 scans under the original glass 119 on which the original is placed, and the original is irradiated with light. When scanning is performed by the lamp 123, the lamp 12
The light emitted from 3 is reflected, and the reflected light is guided to the lens unit 135. The reflected light is inverted by the lens unit 135 and is exposed on the charged photoconductor 103 through the slit glass 107. When the light is exposed,
The charge on the surface of the photoconductor 103 is lost and an electrostatic latent image is formed.

In the developing device 109, the stirring roller 201
The toner 110 and the carrier that are agitated and friction-charged are sent to the magnet roller 203 by the supply roller 202. Tona-1 sent to the magnet roller 203
10 and the carrier are S in the magnet roller 203.
A magnetic brush is formed by the magnetic force lines formed between the poles and the N poles. The carrier is always magnetically attracted to the magnet roller 203, and the toner 110 is electrically attracted to the carrier.

Then, when the magnet roller 203 and the photoconductor 103 rotate and the magnetic brush and the electrostatic latent image on the photoconductor 103 come close to each other, the toner is attracted by the stronger electrostatic attraction of the electrostatic latent image. 110 separates from the carrier and adheres to the electrostatic latent image. The toner 110 attached to the electrostatic latent image forms a toner image. During development, the developing bias is applied to the magnet roller 203 and the photoconductor 10 by a voltage device (not shown).
The unnecessary toner 110 is prevented from adhering to the photoconductor 103 over the period of 3.

On the other hand, the paper stored in the paper feed cassette 141 is pulled out by the pickup roller 143,
Among the pulled-out sheets, only one sheet is sent to the registration roller 149 by the rotation of the sheet feeding roller 145 and the separation roller 147. The registration roller 149 aligns the leading edge of the sheet and then sends the sheet between the photoconductor 103 and the transfer device 111 to superimpose it on the electrostatic latent image on the photoconductor 103. On the back side of this fed paper,
The toner image is transferred onto the paper by the operation of the transfer device 111. The sheet on which the toner image is formed in this manner is peeled from the surface of the photoconductor 103 by the peeling device 113, is conveyed on the conveyor belt 151, and reaches the fixing device 153.

In the fixing device 153, the heat roller 15 heated by a heat lamp 155 incorporated in advance is used.
7 and the pressure roller 159 rotate in their respective viewpoint directions while partially pressure-bonding. Heat roller 157 and pressure roller
When the roller 159 is rotated, the toner image is fixed onto the paper by passing the paper so that the toner image is on the heater-roller side through the pressure-bonded portions of these two rollers. That is, the heat of the heat roller 157 melts the toner 110, the pressure of the pressure roller 159 enhances the heat conduction efficiency, and the toner is soaked between the fibers of the paper.

The sheet on which the copied image is formed through the above process is ejected to the sheet ejection tray 171 through the sheet ejection roller 161. (Example 1) The composition of the toner was as shown below.

Styrene-acrylic resin 100 parts by weight (CPR-600B, manufactured by Mitsui Toatsu Chemicals, Inc.) Carbon black 5 parts by weight (MA-100, manufactured by Mitsubishi Kasei) 1 part by weight low molecular weight polypropylene wax (Viscole 660P, The material of the above formulation was melted and kneaded under heating, cooled, pulverized, and classified to obtain toner particles having a volume average particle diameter of 9 μm and a particle diameter of 5 to 14 μm. To 100 parts by weight of this toner, 0.5 parts by weight of hydrophobic silica (R-972, manufactured by Nippon Aerosil Co., Ltd.) was used with a Henschel mixer (manufactured by Mitsui Miike Co., Ltd.), and the peripheral speed of the blade tip was 20 m /. s, the blade was rotated for 3 minutes to obtain a toner. This toner was sieved by two different methods shown in (a) and (b) below. Two types of toner were obtained.

(A) Gyro shifter (manufactured by Tokuju Kosakusho,
GS-C type) and a clogging removal brush at the same time, and the above toner is subjected to 80K with a 200 mesh SUS sieve.
The toner was passed through forcibly at a throughput of g / hour to obtain a toner having a desired particle size.

(B) Using a vibrating screen (manufactured by Tokuju Kosakusho, TM type), while vibrating the toner, an S of 200 mesh
It was passed through a US sieve by free fall to obtain a toner having a desired particle size with a throughput of 50 Kg / hour.

Two toners obtained in (a) and (b) are used.
Toner was obtained by mixing at a ratio of 5:75 (weight). Fluidity of this toner, cartridge remaining amount (%) when used in an electrophotographic copying machine, toner scattering, charge amount (Q distribution change)
(See FIG. 1), toner density ratio (T / C), and image density (ID) change were measured and evaluated. The results are shown in Table 1 below.

The fluidity of the toner was measured as follows. 20 g of the toner was collected on a 100-mesh sieve and sieved with a powder tester (manufactured by Hosokawa Micron Co., Ltd.) for 30 minutes, and the weight of the toner remaining on the sieve was measured. .

In order to evaluate the charge amount distribution of the toner, the toner density ratio (T / C) to the carrier and the image density (ID) change, a commercially available copying machine having a two-component developing device shown in FIG. 3 (trade name: Rhodry BD-502
0, manufactured by Toshiba Corporation). Here, the charge amount distribution is measured by E-SPART ANALYZER (manufactured by Hosokawa Micron Co., Ltd.), and the toner concentration ratio is obtained by washing a certain amount of the developer with alcohol and measuring the weight when the toner is removed. I asked. The image density was measured by a Macbeth densitometer. In addition, the vertical axis number fractions (number fraction) shown in FIG. 1 and FIG.
Ion) represents the existence probability of q (charge amount) / d (toner diameter), and is such that the area in the curve is always 1. Therefore, when the peak value of the portion surrounded by the curve is small, the range of q / d is wide, which means that the distribution of the charge amount of the toner is wide.

(Example 2) Two kinds of toners (a) and (b) obtained in the same manner as in Example 1 were mixed at a ratio of 75:25 (weight) to obtain a toner.

The fluidity of the toner, the cartridge remaining amount (%) when used in an electrophotographic copying machine, the toner scattering, the charge amount (Q distribution change) (see FIG. 1), the toner density ratio (T /
C) and image density (ID) change were measured and evaluated in the same manner as in Example 1. The results are also shown in Table 1 below.

(Example 3) Two kinds of toners (a) and (b) obtained in the same manner as in Example 1 were mixed at a ratio of 50:50 (weight) to obtain a toner.

The fluidity of the toner, the remaining amount (%) of the cartridge when used in an electrophotographic copying machine, the toner scattering, the charge amount (Q distribution change) (see FIG. 1), and the toner density ratio (T /
C) and image density (ID) change were measured and evaluated in the same manner as in Example 1. The results are also shown in Table 1 below.

Comparative Example 1 Using only the toner (a) obtained in Example 1, its fluidity, cartridge remaining amount (%) when used in an electrophotographic copying machine, toner scattering, charge amount (Q).
Distribution change) (see FIG. 2), toner concentration ratio (T / C),
The image density (ID) change was measured and evaluated in the same manner as in Example 1. The results are also shown in Table 1 below.

Comparative Example 2 Using only the toner (b) obtained in Example 1, its fluidity, cartridge remaining amount (%) when used in an electrophotographic copying machine, toner scattering, charge amount (Q).
Distribution change) (see FIG. 1), toner concentration ratio (T / C),
The image density (ID) change was measured and evaluated in the same manner as in Example 1. The results are also shown in Table 1 below.

[0063]

[Table 1]

As is clear from the results shown in Table 1, the toners of Examples 1 to 3 have good and appropriate fluidity, and the triboelectric charge distribution does not change even after repeated development by continuous use, resulting in a sharp image. Is. Further, the toner / carrier density ratio and the image density did not fluctuate, and the toner remaining amount in the cartridge and the toner scattering were small, which were all excellent.

On the other hand, although the toner of Comparative Example 1 has extremely good fluidity, the triboelectrification distribution becomes broad and the toner concentration ratio (T / C) is lowered in repeated development by continuous use. The image density (ID) was recognized, and a large amount of toner scattering due to too good fluidity was also recognized. Further, since the toner of Comparative Example 2 has poor fluidity,
There is a problem that the remaining amount of the cartridge is large and the image density (ID) is reduced due to the increase of the charge amount.

[0066]

According to the present invention, a toner having a good fluidity obtained by vibrating the sieve and allowing the toner to freely fall is added to the toner obtained by forcibly passing the toner by brushing the sieve. It becomes possible to obtain a toner having good fluidity and stable triboelectrification characteristics by mixing with. In addition, it is possible to obtain a clear image that does not depend on the environment and has no toner fog or toner scattering, and such toner characteristics are retained even during repeated development by continuous use, and the quality of the copied image is improved. It has many excellent effects such as no decrease.

[Brief description of drawings]

FIG. 1 is a diagram showing a triboelectric charge distribution of toners according to Examples 1, 2, 3 and Comparative Example 1 of the present invention.

FIG. 2 is a diagram showing a triboelectric charge distribution of a toner according to Comparative Example 2.

FIG. 3 is a side view showing an outline of an image developing apparatus in which the toner according to the present invention is used.

[Explanation of symbols]

Reference numeral 101 ... Copier main body, 103 ... Photoconductor, 105 ... Charging charger, 109 ... Developing device, 110 ... Toner, 111 ... Transfer device, 113 ... Peeling device, 115 ...
Cleaning device, 117 ... Static eliminator, 153 ... Fixing device, 157 ... Heat roller, 159 ... Pressure roller
La, 201 ... stirring roller, 202 ... supply roller,
203 ... Magnet roller.

Claims (2)

[Claims] 1. A step of: (a) using a sieve having a predetermined mesh for a toner containing one or more external additives, vibrating the sieve, and free-falling the toner to obtain a toner having a predetermined particle size; b) a step of obtaining a toner having a predetermined particle size by using a sieve of a predetermined mesh for a toner containing one or more kinds of external additives, brushing the sieve to forcefully pass through the sieve, and And a step of mixing the toner obtained in the step (b) with the toner obtained in the step (b) at a mixing ratio of 95: 5 to 5:95. 2. The toner obtained in the step (a) and the toner obtained in the step (b) are mixed at a mixing ratio of 75:25 to 25:75. Toner manufacturing method.