JP2000292973A - Toner and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polymer toner prevented from occurrence of image defects such as fog, black spots or the like even in the case of being used for image formation for a long period and to provide its manufacturing method. SOLUTION: This toner is obtained by salting out at least fine colorant particles and fine resin particles and fused to each other. The fine colorant particles are dispersed into an aqueous medium containing a surfactant by a stirring device provided with a screen and a rotor rotating at high speed and having a weight average particle diameter of 30-300 nm. The toner manufacturing method has the processes for dispersing the above fine colorant particles and the fine particles of these colorant and the binder resin, and for salting out and melt attaching them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a toner and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a technique for producing a toner for developing an electrostatic latent image by a polymerization method is known. For example, toner particles are obtained by a suspension polymerization method. However, the toner particles obtained by the suspension polymerization method are spherical and have a disadvantage that cleaning properties are poor. On the other hand, as a method for obtaining irregular (non-spherical) toner particles,
There is known a method of associating (aggregating and fusing) resin fine particles and colorant fine particles obtained by an emulsion polymerization method (for example, see JP-A-60-225170). When toner particles are formed by associating resin fine particles and colorant fine particles, (1) the colorant is reliably introduced into the toner particles (the colorant is not released), and (2)
It is required that there is no difference in the content ratio of the colorant between the toner particles (the dispersion state of the colorant is uniform).

[0003]

However, conventionally known toners formed by associating resin fine particles and colorant fine particles do not satisfy the above requirements (1) and (2). .

When a colorant in a free state is present in a toner, the colorant adheres to a carrier or a developer conveying member, and as a result, the effect of imparting charge to the toner is reduced and fogging of a formed image is caused. Occurs. Further, when the colorant in a free state adheres to the photoreceptor or the like, image defects such as black spots occur. Further, the difference (distribution) in the content ratio of the colorant between the toner particles appears as a difference in the charging characteristics (charge amount distribution) between the toner particles. For this reason,
When a toner having a different content ratio of the colorant (a toner having a wide charge amount distribution) is used for image formation, fogging may occur in a formed image.

As a result of repeated studies by the present inventors, in order to form a toner satisfying the above-mentioned requirements (1) and (2), the colorant fine particles used for association with the resin fine particles must be mixed with an aqueous medium. It was found that the state of dispersion (particle size distribution) in the medium was important, and based on such findings, a further study was conducted on the method of dispersing the colorant fine particles.

The dispersing machine used for dispersing the colorant in the aqueous medium includes an ultrasonic dispersing machine, a pressure dispersing machine such as Menton Gorin and a pressure homogenizer, a sand grinder, a Getzman mill, and a diamond. A media type disperser such as a fine mill can be used.

However, in the dispersion processing by the ultrasonic disperser, there is a distribution in the state of application of the ultrasonic waves.
The particle size distribution of the colorant is considerably broad. Also,
A dispersion of colorant fine particles having a sharp particle size distribution cannot be obtained even by a dispersion treatment using a pressure disperser. Further, in the dispersion treatment by the medium type disperser, crushed pieces (fine impurities) generated by the abrasion of the medium remain in the dispersion of the colorant fine particles, and the toner obtained by using such a dispersion is used for image formation. In the case where the photoreceptor is damaged by the crushed pieces,
Image defects such as black spots may occur in the formed image.

The present invention has been made based on the above circumstances. A first object of the present invention is to provide a colorant that is surely introduced into toner particles, and there is no difference in the content of the colorant between the toner particles. An object of the present invention is to provide a toner which does not cause image defects such as spots and a method of manufacturing the toner. A second object of the present invention is to provide a toner which does not cause image defects due to fine impurities such as crushed pieces of a medium, and a method for producing the same.

[0009]

Means for Solving the Problems As a result of extensive studies by the present inventors, it was found that by dispersing fine colorant particles in an aqueous medium in accordance with a specific dispersion treatment method, a suitable average particle size and a sharp particle size can be obtained. A dispersion of colorant fine particles having a distribution is obtained, and the colorant fine particles (dispersed particles) are salted out / fused with the resin fine particles to obtain toner particles into which the colorant is surely and uniformly introduced. This led to the completion of the present invention based on such knowledge.

That is, the toner of the present invention is a toner obtained by salting out / fusing at least colorant fine particles and resin fine particles, wherein the colorant fine particles define a stirring chamber (M) in a screen (1). And a stirrer provided with a rotor (2) rotating at high speed in the stir chamber (M),
It is a dispersed particle having a weight average particle size of 30 to 300 nm dispersed in an aqueous medium containing a surfactant.

The toner according to the present invention is obtained by salting out / fusing at least colorant fine particles and resin fine particles, wherein the colorant fine particles define a stirring chamber (M). And a rotor (2) rotating at a high speed in the stirring chamber (M), and dispersed in an aqueous medium containing a surfactant by the action of a shearing force.
It is a dispersed particle having a weight average particle size of 30 to 300 nm.

The toner of the present invention is obtained by salting out / fusing at least colorant fine particles and resin fine particles, wherein the colorant fine particles define a stirring chamber (M) in a screen (1). And the rotor (2) rotating at a high speed in the stirring chamber (M), and were dispersed in an aqueous medium containing a surfactant by the action of shear force, collision force, pressure fluctuation, cavitation, and potential core. , And are dispersed particles having a weight average particle size of 30 to 300 nm.

The toner of the present invention is obtained by salting out / fusing at least colorant fine particles and resin fine particles. The colorant fine particles include a screen (1) and a rotor (2). Using a dispersion container equipped with a stirring device, and in a water-based medium containing a surfactant accommodated in the dispersion container, a colorant is jetted downward from a stirring chamber of the stirring device, whereby the aqueous medium is dispersed. It is a dispersed particle having a weight average particle size of 30 to 300 nm dispersed therein.

The toner of the present invention is obtained by salting out / fusing at least colorant fine particles and resin fine particles. The colorant fine particles include a screen (1) and a rotor (2). Using a dispersion container equipped with a stirrer, and in a water-based medium containing a surfactant contained in the dispersion container, the colorant is ejected in a horizontal direction from a stirring chamber of the stirrer, whereby the aqueous system is dispersed. It is a dispersed particle having a weight average particle diameter of 30 to 300 nm dispersed in a medium.

According to the production method of the present invention, the surface activity is controlled by a stirrer provided with a screen (1) for partitioning the stirring chamber (M) and a rotor (2) rotating at high speed in the stirring chamber (M). Weight average particle size in the aqueous medium containing the agent is 30 to
The method is characterized by including a step of dispersing 300 nm colorant fine particles and salting out / fusing the colorant fine particles and the resin fine particles.

Further, in the production method of the present invention, the stirring chamber (M)
(1) for forming a partition and the stirring chamber (M)
By the action of the shear force generated by the rotor (2) rotating at high speed in the inside, the colorant fine particles having a weight average particle size of 30 to 300 nm are dispersed in an aqueous medium containing a surfactant, and the colorant fine particles and the resin are dispersed. It is characterized by including a step of salting out / fusing with the fine particles.

Further, in the production method of the present invention, the stirring chamber (M)
(1) for forming a partition and the stirring chamber (M)
Colorant having a weight average particle size of 30 to 300 nm in an aqueous medium containing a surfactant due to the action of shear force, collision force, pressure fluctuation, cavitation and potential core generated by a rotor (2) rotating at high speed in the inside. Fine particles are dispersed, and the colorant fine particles and the resin fine particles are salted out /
It is characterized by including a step of fusing.

Further, the production method of the present invention uses a dispersion container equipped with a stirring device having a screen (1) and a rotor (2), and contains a surfactant contained in the dispersion container. In an aqueous medium, a colorant having a weight average particle size of 30 to 300 nm is dispersed in the aqueous medium by jetting a colorant downward from a stirring chamber of the stirring device. And a step of salting out / fusion.

Further, the production method of the present invention uses a dispersion container provided with a stirring device having a screen (1) and a rotor (2), and contains a surfactant contained in the dispersion container. In an aqueous medium, a colorant is ejected in a horizontal direction from a stirring chamber of the stirrer to disperse colorant fine particles having a weight average particle diameter of 30 to 300 nm in the aqueous medium. It is characterized by including a step of salting out / fusing with the fine particles.

[0020]

By the action of the shear force generated by the screen and the rotor, the agglomerated particles of the colorant are crushed, and a suitable average particle size (weight average particle size: 30 to 500 nm) and a sharp particle size distribution (standard deviation (standard deviation)) A dispersion of colorant fine particles (fine particles close to primary particles) having a σ) of 30 or less) is obtained. And such colorant fine particles (dispersed particles)
Is subjected to salting-out / fusion with resin fine particles, so that the colorant fine particles are surely introduced into the formed toner particles, so that the colorant is not released, and the colorant is interposed between the toner particles. Does not vary.
As a result, according to the toner of the present invention including the toner particles, even when subjected to long-term image formation, image defects such as fog and black spots do not occur. Further, since the colorant fine particles are dispersed without using a medium, according to the finally obtained toner, image defects due to fine impurities such as crushed pieces of the medium do not occur.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. <Colorant Fine Particles> The colorant fine particles used to obtain the toner of the present invention include: a screen that defines a stirring chamber;
The fine particles are finely dispersed in an aqueous medium containing a surfactant by the action of shearing force generated by the rotor rotating at high speed in the stirring chamber (further, the action of collision force, pressure fluctuation, cavitation, and potential core). .

The weight average particle size (dispersion particle size) of the colorant fine particles is 30 to 500 nm, preferably 50 to 30 nm.
0 nm. If the weight average particle size is less than 30 nm, the particles float in an aqueous system intensely, making it difficult to incorporate them into the toner. On the other hand, when the weight average particle size exceeds 500 nm, the particles are not appropriately dispersed in an aqueous system and are likely to settle, so that it is difficult to introduce the particles into the toner particles, and a free colorant is generated. Easier to do. The weight average particle diameter of the colorant fine particles is a value measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.).

The particle size distribution of the colorant fine particles is preferably 30 or less in standard deviation, more preferably 20 or less. When the particle size distribution of the colorant fine particles is 30 or less in standard deviation, the distribution can be sharpened, the colorant fine particles can be reliably taken in, and the release of the colorant fine particles hardly occurs. In addition,
The “particle size distribution of the colorant fine particles” indicates a standard deviation measured by an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.).

The fine particles of the colorant used for obtaining the toner of the present invention are prepared by adding a colorant to an aqueous medium containing a surfactant, and performing preliminary dispersion (coarse dispersion) using a propeller stirrer or the like. The liquid (dispersed liquid of the aggregated particles of the colorant) is supplied to a stirrer provided with a screen that defines a stirring chamber and a rotor that rotates at high speed in the stirring chamber, and the dispersion treatment (fine dispersion treatment) is performed by the stirring device. )).

In the present invention, as a stirring device which can be used for dispersion treatment for obtaining colorant fine particles,
"CLEARMIX" (manufactured by M Technique Co., Ltd.) can be mentioned. This "Clear Mix" is composed of a rotor (stirring blade) that rotates the liquid to be treated at a high speed and a fixed screen (fixed ring) surrounding the rotor, which includes shear force, collision force, pressure fluctuation, cavitation, and potential core. Has a structure that produces the action of emulsification.
It performs dispersion. That is, this “Clear Mix” is used for the production of an emulsion (dispersion of liquid fine particles), but the present inventors disperse the colorant fine particles (solid) in an aqueous medium by using this apparatus. It has been found that a dispersion of colorant fine particles having a suitable average particle diameter and a sharp particle diameter distribution can be obtained by using a dispersion apparatus for the above.

FIG. 1 is a schematic view showing a rotor rotating at high speed and a fixed screen surrounding the rotor. In FIG. 1, reference numeral 1 denotes a screen, M denotes a stirring chamber defined by the screen 1, Reference numeral 2 denotes a rotor that rotates at high speed in the stirring chamber M.

The rotor 2 is a stirring blade which rotates at a high speed.
2,000 rpm, preferably 10,000 to 2
1,500 rpm. The peripheral speed of the tip of the rotor 2 is usually set to 10 to 40 m / sec, preferably 15 to 30 m / sec.
m / sec.

The screen 1 surrounding the rotor 2 is composed of a stationary ring in which a number of slits (not shown) are formed.
Here, the width of the slit is 0.5 to 5 mm,
Preferably it is 0.8 to 2 mm. The number of slits is set to 10 to 50, preferably 15 to 30.
It is a book. The gap (clearance) between the rotor 2 and the screen 1 is usually 0.1 to 1.5 mm, preferably 0.2 to 1.0 mm.

The average particle size and the particle size distribution of the colorant fine particles can be adjusted by controlling the number of revolutions of the rotor 2 and the like, and can also be adjusted by selecting the shapes of the screen 1 and the rotor 2. be able to. Specifically, the screens (S1.0-24, S1.5-24, S1.5-
18, S2.0-18, S3.0-9) and standard equipment such as rotors (R1 to R4) can be used in combination, but it is also possible to produce a desired shape by itself.

FIG. 2 is a schematic diagram showing a continuous processing apparatus (Clearmix) equipped with a rotor and a screen. The pre-dispersed dispersion liquid (pre-dispersion liquid) is supplied to the stirring chamber between the screen 1 and the rotor from the pre-dispersion liquid inlet 4 shown in FIG. Screen 1 and rotor
A temperature sensor 6, a cooling jacket 7, and a cooling coil 8 are arranged by being surrounded by the pressurized vacuum attachment 3. The agglomerated particles of the colorant in the preliminary dispersion are crushed (finely dispersed) by applying a shearing force generated by the rotor and the screen 1 rotating at a high speed.

That is, the agglomerated particles of the colorant in the pre-dispersion liquid supplied to the zone (stirring chamber) between the screen 1 and the rotor are subjected to the shearing force generated by the screen 1 and the high-speed rotating rotor ( Mechanical energy) and, together with the action of shear forces, are crushed (finely dispersed) by the action of impact forces, pressure fluctuations, cavitation and potentiometers, thereby forming colorant fine particles Is done. The dispersion of the coloring agent fine particles is ejected from the slit of the screen 1 into the pressurized vacuum attachment 3. As a result, colorant fine particles (dispersed particles) having a suitable average particle size and a sharp particle size distribution are formed. The dispersion containing the colorant fine particles is sent from the dispersion outlet 5 to the next step.

The mechanism by which the colorant fine particles (dispersed particles) are formed by the high-speed rotating rotor and the screen has the following effects.

(1) Rotor rotating at high speed (stirring blade)
There is a large velocity gradient near the surface, and a high shear rate region is formed near the surface. Agglomerated particles of the colorant that have been subjected to the shearing force are crushed into colorant fine particles having a sharp particle size distribution.

(2) A vacuum portion (cavitation) is generated behind the rotor (stirring blade) rotating in the liquid when the rotation speed is high. The bubbles generated by this will be destroyed when the flow velocity decreases,
An impact pressure is generated due to the compression of the bubbles, and the agglomerated particles of the colorant are crushed by the impact pressure, resulting in colorant fine particles having a sharp particle size distribution.

(3) High-speed rotating rotor (stirring blade)
When the pressure energy applied to the preliminary dispersion is rapidly released, the kinetic energy increases. A pressure wave is generated when the pre-dispersion liquid flowing by the rotor repeatedly passes through the open part (slit part) and the closed part (non-slit part) of the screen. The aggregated particles of the colorant are crushed by the pressure wave (pressure fluctuation) to become colorant fine particles having a sharp particle size distribution.

(4) When the pre-dispersion liquid having a large kinetic energy collides with the screen or other wall, the agglomerated particles of the colorant which have been subjected to the collision force are broken up, and the colorant fine particles having a sharp particle size distribution. Becomes

(5) When the dispersion having the velocity energy passes through the slit of the screen, it becomes a jet (jet stream). The surrounding fluid is sucked at a high speed in the potential core (velocity region not affected by the viscous flow) in the jet. Agglomerated particles of the colorant that have received this energy are crushed into colorant fine particles having a sharp particle size distribution.

The dispersion time for obtaining the dispersion of the colorant fine particles is not particularly limited. By circulating for 5 to 30 minutes in the case of a batch system and 5 or more passes in the case of a continuous system, the intended dispersion state can be achieved. Preferably, 7 to 7 in the case of batch type
The duration is 25 minutes, and in the case of a continuous system, the number of passes is 5 to 20. If the time is too short, the desired dispersion cannot be obtained, and if it is too long, the dispersion becomes excessive and the amount of the fine particles increases, which is not preferable.

The colorant fine particles used for obtaining the toner of the present invention are prepared by using a dispersion container provided with a stirring device having a screen and a rotor, and stirring the dispersion in an aqueous medium contained in the dispersion container. It can also be formed by ejecting a colorant (aqueous medium containing a colorant) from the stirring chamber of the device.

FIG. 3 is a schematic view showing a dispersion container provided with such a stirring device (Clear Mix), and a batch type dispersion treatment is performed by such a device. In FIG. 3, reference numeral 11 denotes a dispersion container, 12 denotes a stirring device, and 13 denotes a stirring shaft for driving the stirring device 12. The stirring device 12 has the same configuration (screen and rotor) as that shown in FIG.

Pre-dispersion (dispersion of agglomerated particles of colorant)
Enters the stirring chamber from the upper part of the stirring device 12 and is stirred by strong shearing force, impact force and turbulence generated between the rotor and the screen rotating at a high speed, and has a weight average particle diameter of 30.
Colorant fine particles of about 300 nm are formed, and are ejected into the dispersion container 11 from the slits of the screen. In the step of dispersing the colorant fine particles, the dispersion container 11 has a jacket structure,
Hot water or steam, and if necessary, cold water or the like may flow through the jacket to control the temperature inside the dispersion container 11.

In the case where the batch type dispersion treatment is performed using the dispersion container shown in FIG. 3, the direction in which the colorant is ejected from the stirring chamber of the stirring device 12 (the direction in which the colorant fine particles are ejected into the aqueous medium). Is preferably downward or in the horizontal direction. By jetting the colorant (colorant fine particles) downward or in the horizontal direction, the aqueous medium in the dispersion container 11 flows as shown by the arrow F. As a result, the colorant is jetted downward, and the flow flows along the wall. It rises and circulates again into Clearmix. Therefore, the dispersion step can be surely repeated, and the dispersion energy can be uniformly applied. As a result, it is presumed that the dispersion diameter and the like of the colorant can be made uniform. This makes it possible to efficiently form colorant fine particles having a sharp particle size distribution.

<Toner of the Present Invention> The toner of the present invention is obtained by salting out / fusing the above-mentioned colorant fine particles (colorant fine particles having a preferable average particle diameter and a sharp particle diameter distribution) with resin fine particles. can get. In the present invention, “salting out / fusion” means that salting out (aggregation of fine particles) and fusion (loss of interface between fine particles) occur simultaneously, or an act of causing salting out and fusion simultaneously. Say. In order to simultaneously carry out the salting-out and the fusion, it is necessary to aggregate the fine particles (resin fine particles, colorant fine particles) under a temperature condition equal to or higher than the glass transition temperature (Tg) of the resin constituting the fine resin particles.

[Molecular Weight of Resin Constituting Toner] In the toner of the present invention, in order to improve the anti-offset property and the like while ensuring good adhesion to the image support, a low molecular weight is contained in the toner particles. It is preferable that a high molecular weight resin and a high molecular weight resin are contained.

Here, the "low molecular weight resin" constituting the toner of the present invention refers to a resin having a weight average molecular weight of less than 50,000 and having a weight average molecular weight of 1,000 to 4,
Those in the range of 9,999 are preferred. The low molecular weight resin has a molecular weight distribution in the range of 1,000 to 30,000, particularly 1,500 in the molecular weight distribution measured by GPC.
Preferably, it has a peak or shoulder in the range of ２０20,000.

The "high molecular weight resin" constituting the toner of the present invention refers to a resin having a weight average molecular weight of 50,000 or more, and this weight average molecular weight is from 50,000 to 50,000.
Those in the range of 1,200,000 are preferred. In addition, the high molecular weight resin preferably has a peak or a shoulder in a range of 50,000 to 1,000,000, particularly in a range of 50,000 to 500,000 in a molecular weight distribution measured by GPC. .

The ratio of the high molecular weight resin to the low molecular weight resin constituting the toner of the present invention is preferably such that “high molecular weight resin: low molecular weight resin (weight)” is 1: 1 to 1:10. If the proportion of the high molecular weight resin is too large, the adhesiveness of the toner to the image support (transfer paper) is poor, while if the proportion of the high molecular weight resin is too small, The effect of improving the anti-winding property of the image support cannot be sufficiently exhibited.

The weight average molecular weight of the resin components (high molecular weight resin and low molecular weight resin) constituting the toner of the present invention is preferably in the range of 30,000 to 500,000, more preferably 40,000 to 400. 000
Range.

The molecular weight distribution of the resin constituting the toner of the present invention is a molecular weight in terms of styrene measured using GPC (gel permeation chromatography). As a method of measuring the molecular weight of the resin by GPC, 1 cc of THF is added to 0.5 to 5.0 mg (specifically, 1 mg) of a measurement sample, and the mixture is sufficiently stirred by using a magnetic stirrer or the like at room temperature. To dissolve. Then
After processing with a membrane filter having a pore size of 0.45 to 0.50 μm, the mixture is injected into GPC. The GPC measurement conditions are as follows: the column is stabilized at 40 ° C., THF is flowed at a flow rate of 1 cc per minute, and about 100 μl of a 1 mg / cc concentration sample is injected for measurement. The column is preferably used in combination with a commercially available polystyrene gel column. For example, Shodex GPC manufactured by Showa Denko
KF-801,802,803,804,805,8
06807, and TSKgelG manufactured by Tosoh Corporation
1000H, G2000H, G3000H, G4000
H, G5000H, G6000H, G7000H, TS
Combinations of Kguardcolumn and the like. It is preferable to use a refractive index detector (IR detector) or a UV detector as the detector. In the measurement of the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve measured using monodisperse polystyrene standard particles. It is preferable to use about 10 polystyrenes for the calibration curve measurement.

[Resin Fine Particles] The resin fine particles used for obtaining the toner of the present invention include resin fine particles composed of a low molecular weight resin, resin fine particles composed of a high molecular weight resin, and a core composed of a high molecular weight resin and a shell composed of a low molecular weight resin. Composite resin fine particles described below.

The high molecular weight resin constituting the resin fine particles or the high molecular weight resin constituting the core (particles) of the composite resin fine particles has a molecular weight distribution of 5 as measured by GPC.
In the range from 0000 to 1,000,000, in particular 50,000
It preferably has a peak or a shoulder in the range of 00 to 500,000. Further, the low molecular weight resin constituting the resin fine particles or the low molecular weight resin constituting the shell of the composite resin fine particles has a molecular weight distribution measured by GPC in the range of 1,000 to 30,000, particularly 1,500.
It preferably has a peak or shoulder in the range of ２０20,000.

Weight average particle size of resin fine particles (dispersion particle size)
Is preferably in the range of 20 to 500 nm, more preferably in the range of 30 to 400 nm. The weight average particle size was measured using an electrophoretic light scattering photometer “ELS-80”.
0 "(manufactured by Otsuka Electronics Co., Ltd.).

In order to obtain a toner containing a low molecular weight resin and a high molecular weight resin in toner particles, (1) resin fine particles composed of a low molecular weight resin, resin fine particles composed of a high molecular weight resin, and colorant fine particles And (2) salting out the composite resin fine particles and the colorant fine particles.
The method of fusing may be mentioned, and among these, the method of the above (2) may be employed from the viewpoint of obtaining a toner having excellent homogeneity in composition, molecular weight, and surface characteristics among toner particles. preferable.

[Glass Transition Temperature and Softening Point of Resin Component] The glass transition temperature (Tg) of the resin component (the resin introduced by the fine resin particles) constituting the toner of the present invention is 1
The temperature is preferably in the range of 0 to 75 ° C, more preferably 40 to 65 ° C. Further, the softening point of the resin component is preferably in the range of 80 to 220 ° C.

Here, the glass transition point (Tg) of the resin component
Means a value measured by DSC, and an intersection between the baseline and the slope of the endothermic peak is defined as a glass transition point. Specifically, using a differential scanning calorimeter, the temperature was raised to 100 ° C., left at that temperature for 3 minutes, and then dropped to 10 ° C./min.
And cool to room temperature. Next, when this sample was measured at a heating rate of 10 ° C./min, an extension line of the base line below the glass transition point and a tangent line showing the maximum slope from the rising portion of the peak to the top of the peak. The intersection is indicated as the glass transition point. Here, as the measuring device,
Perkin Elmer's DSC-7 or the like can be used.

The softening point of the resin component refers to a value measured using a Koka type flow tester. Specifically, using a Koka type flow tester “CFT-500” (manufactured by Shimadzu Corporation), the diameter of the pores of the die is 1 mm, and the length is 1 m.
m, the temperature corresponding to 1/2 of the height from the outflow start point to the outflow end point when a 1 cm ³ sample is melted out under the conditions of a load of 20 kg / cm ² and a heating rate of 6 ° C./min. Shown as dots.

[Monomer for Obtaining Resin Fine Particles] The polymerizable monomer for obtaining the resin fine particles (high-molecular-weight resin and low-molecular-weight resin) used for obtaining the toner of the present invention is a radical polymerizable monomer. A monomer can be used as an essential component, and a crosslinking agent can be used if necessary. In addition, it is preferable to use at least one kind of monomer selected from “radical polymerizable monomer having an acidic group” and “radical polymerizable monomer having a basic group”.

The radical polymerizable monomer is not particularly limited, and conventionally known monomers can be used alone or in combination of two or more depending on required characteristics. Such radical polymerizable monomers include aromatic vinyl monomers, (meth) acrylate monomers, vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers, and the like. Olefin monomer,
Halogenated olefin monomers and the like can be mentioned.

Examples of the aromatic vinyl monomer include styrene, o-methylstyrene, m-methylstyrene and p-methylstyrene.
-Methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octyl Styrene monomers such as styrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4-dimethylstyrene, and 3,4-dichlorostyrene, and derivatives thereof.

Examples of (meth) acrylate monomers include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, and methacrylic acid. Examples include ethyl, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, and diethylaminoethyl methacrylate.

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, vinyl benzoate and the like.

Examples of the vinyl ether monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether and the like.

Examples of the monoolefin monomer include ethylene, propylene, isobutylene, 1-butene,
-Pentene, 4-methyl-1-pentene and the like.

Examples of the diolefin monomer include butadiene, isoprene, chloroprene and the like.

Examples of the halogenated olefin monomer include:
For example, vinyl chloride, vinylidene chloride, vinyl bromide and the like can be mentioned.

As a crosslinking agent for improving the properties of the toner, a radical polymerizable crosslinking agent may be added. Examples of such a radical polymerizable crosslinking agent include compounds having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate. The ratio of the radical polymerizable crosslinking agent in the monomer (monomer mixture) used is preferably 0.1 to 10% by weight.

Examples of the radical polymerizable monomer having an acidic group include carboxylic acids such as acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, monobutyl maleate and monooctyl maleate. Group-containing monomers: Sulfonic acid group-containing monomers such as styrene sulfonic acid, allyl sulfosuccinic acid, and octyl allyl sulfosuccinate are exemplified. All or a part of the radical polymerizable monomer having an acidic group may have a structure of an alkali metal salt such as sodium or potassium or an alkaline earth metal salt such as calcium. The proportion of the radical polymerizable monomer having an acidic group in the monomer (monomer mixture) used is preferably 0.1 to 20% by weight, more preferably 0.1 to 15% by weight. It is.

Examples of the radical polymerizable monomer having a basic group include primary amine, secondary amine, tertiary amine,
Examples include amine compounds such as quaternary ammonium salts. Specific examples of such an amine compound include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, and quaternary ammonium salts thereof, 3-dimethylaminophenyl acrylate, 2-hydroxy-3- Methacryloxypropyltrimethylammonium salt, acrylamide, N-butylacrylamide, N, N-dibutylacrylamide, piperidylacrylamide, methacrylamide, N-butylmethacrylamide, N-octadecylacrylamide; vinylpyridine, vinylpyrrolidone;
Examples thereof include vinyl N-methylpyridinium chloride, vinyl N-ethylpyridinium chloride, N, N-diallylmethylammonium chloride, and N, N-diallylethylammonium chloride. The ratio of the radical polymerizable monomer having a basic group in the monomer (monomer mixture) used is preferably 0.1 to 20% by weight, more preferably 0.1 to 15% by weight. %.

[Chain Transfer Agent for Obtaining Resin Fine Particles] For the purpose of adjusting the molecular weight of the resin constituting the toner of the present invention, a commonly used chain transfer agent can be used. The chain transfer agent is not particularly limited, and examples thereof include mercaptans such as octyl mercaptan, dodecyl mercaptan, tert-dodecyl mercaptan, and styrene dimers.

[Polymerization Initiator for Obtaining Resin Fine Particles] The radical polymerization initiator for obtaining the resin constituting the toner of the present invention can be appropriately used as long as it is a water-soluble radical polymerization initiator. Specific examples of the radical polymerization initiator include, for example, persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds (4,4′-azobis-4-cyanovaleric acid and its salts, 2,2′-azobis ( 2-amidinopropane) salts, etc.), peroxide compounds and the like. Furthermore, the above-mentioned radical polymerization initiator can be combined with a reducing agent, if necessary, to form a redox initiator. By using the redox initiator, the polymerization activity is increased, the polymerization temperature can be lowered, and the polymerization time can be further reduced. The polymerization temperature is not particularly limited as long as it is equal to or higher than the lowest radical generation temperature of the polymerization initiator, but is, for example, in the range of 50 to 90 ° C. However, by using a polymerization initiator that starts at room temperature such as a combination of hydrogen peroxide and a reducing agent (such as ascorbic acid), polymerization can be performed at room temperature or higher.

[Surfactant for Obtaining Resin Fine Particles] The surfactant used for the emulsion polymerization of the radically polymerizable monomer is not particularly limited. Sodium benzenesulfonate, sodium arylalkylpolyethersulfonate), sulfates (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.), fatty acid salts (sodium oleate, sodium laurate, sodium caprate) And ionic surfactants such as sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.). In addition, polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, an ester of polyethylene glycol and a higher fatty acid, an alkylphenol polyethylene oxide, an ester of a higher fatty acid and a polyethylene glycol, an ester of a higher fatty acid and a polypropylene oxide, and a sorbitan ester Nonionic surfactants such as can be used. These surfactants are used as emulsifiers in the emulsion polymerization step, but may be used for other steps or purpose.

[Colorant Constituting Colorant Fine Particles] Examples of the colorant constituting the colorant fine particles used for obtaining the toner of the present invention include various inorganic pigments and organic pigments. Conventionally known inorganic pigments can be used. Although any pigment can be used, suitable inorganic pigments are exemplified below. Examples of black pigments include furnace black, channel black, acetylene black, thermal black,
Carbon black such as lamp black, and magnetic powder such as magnetite and ferrite are also used. These inorganic pigments can be used alone or in combination of two or more as desired. The content ratio of the inorganic pigment in the toner of the present invention is 2 parts per 100 parts by weight of the resin component (polymer).
To 20 parts by weight, more preferably 3 to 20 parts by weight.
To 15 parts by weight. The content ratio of magnetite in the magnetic toner is preferably from 20 to 60% by weight from the viewpoint of exhibiting desired magnetic properties.

Conventionally known organic pigments can be used. Although any pigment can be used, specific organic pigments are exemplified below. Pigments for magenta or red include C.I. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I. Pigment Red 6, C.I. I.
Pigment Red 7, C.I. I. Pigment Red 15,
C. I. Pigment Red 16, C.I. I. Pigment Red 48: 1, C.I. I. Pigment Red 53: 1,
C. I. Pigment Red 57: 1, C.I. I. Pigment Red 122, C.I. I. Pigment Red 123,
C. I. Pigment Red 139, C.I. I. Pigment red 144, C.I. I. Pigment Red 149, C.I.
I. Pigment Red 166, C.I. I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I.
Pigment Red 222 and the like. Examples of orange or yellow pigments include C.I. I. Pigment Orange 31, C.I. I. Pigment Orange 43, C.I. I.
Pigment Yellow 12, C.I. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I. I. Pigment Yellow 1
7, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 94, C.I. I. Pigment Yellow 13
8, and the like. Green or cyan pigments include C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 1
5: 3, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 60, C.I. I. Pigment Green 7 and the like. These organic pigments can be used alone or in combination of two or more as desired. The content ratio of the organic pigment in the toner of the present invention is preferably 2 to 20 parts by weight, more preferably 3 to 15 parts by weight based on 100 parts by weight of the resin component (polymer).

The colorant (colorant fine particles) constituting the toner of the present invention may be surface-modified. Here, conventionally known surface modifiers can be used, and specifically, silane coupling agents, titanium coupling agents, aluminum coupling agents, and the like can be preferably used.

Examples of the silane coupling agent include alkoxysilanes such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane and diphenyldimethoxysilane, siloxanes such as hexamethyldisiloxane, γ-chloropropyltrimethoxysilane, vinyl Trichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,
γ-ureidopropyltriethoxysilane and the like.

As the titanium coupling agent, for example,
TTS, 9S, 38S, 41B, 46B, 5B, which are commercially available under the trade name "Plenact" manufactured by Ajinomoto Co.
5, 138S, 238S, etc., commercial products A-
1, B-1, TOT, TST, TAA, TAT, TL
A, TOG, TBSTA, A-10, TBT, B-2,
B-4, B-7, B-10, TBSTA-400, TT
S, TOA-30, TSDMA, TTAB, TTOP and the like. As the aluminum coupling agent,
For example, "Plenact AL-M" manufactured by Ajinomoto Co., Inc., and the like can be mentioned.

The addition amount of these surface modifiers is preferably 0.01 to 20% by weight, more preferably 0.1 to 5% by weight, based on the colorant.

Examples of the method for modifying the surface of the colorant fine particles include a method in which a surface modifier is added to a dispersion of the colorant fine particles, and the system is heated and reacted. The surface-modified colorant fine particles are collected by filtration, and are dried after repeated washing and filtering with the same solvent.

[Internal Additives] The toner particles constituting the toner of the present invention may contain various internal additives such as a charge control agent and a fixing property improving agent. Examples of the charge control agent contained in the toner particles include nigrosine dyes, metal salts of naphthenic acid or higher fatty acids, alkoxylated amines, quaternary ammonium salt compounds, azo metal complexes, salicylic acid metal salts or metal complexes thereof. Is mentioned. As the fixability improving agent contained in the toner particles, various known ones which can be dispersed in water can be used. Specific examples include olefin-based waxes such as polypropylene and polyethylene, modified products of these olefin-based waxes, natural waxes such as carbawa wax and rice wax, and amide-based waxes such as fatty acid bisamide. These are preferably used in the form of a dispersion (wax emulsion) dispersed in water.

[Diameter of Toner Particles] The particle diameter of the toner particles constituting the toner of the present invention is 3 to 10 μm in terms of volume average particle diameter.
m is preferable. The volume average particle size of the toner can be measured using a Coulter Counter TA-II, a Coulter Multisizer, SLAD1100 (a laser diffraction particle size measuring device manufactured by Shimadzu Corporation), or the like. In the case of Coulter Counter TAII and Coulter Multisizer, the values measured using an aperture having an aperture diameter of 100 μm and a particle size distribution in the range of 2.0 to 40 μm are shown.

The shape of the toner particles obtained by fusing is such that the arithmetic average value of the shape factor represented by the following equation is 1.
Within a range of 3 to 2.2 and a shape factor of 1.5 to
It is preferable that the number of toner particles in the range of 2.0 is 80% by number or more.

[0082]

Formula: Shape factor = ((maximum diameter / 2) ² × π) /
(Projected Area) In order to determine the shape factor, a photograph in which the toner particles were magnified 500 times with a scanning electron microscope was taken, and then “SCANNING IMAGE” was determined based on the photograph.
Analyze the photographic image using "ANALYSER" (manufactured by JEOL Ltd.). At this time, the shape coefficients of 500 toner particles are measured, and the arithmetic average value is obtained. When the arithmetic average value of the shape coefficient is less than 1.3, the shape becomes rounded, so that the adhesiveness becomes strong, and so-called cleaning failure tends to occur. When the arithmetic average value of the shape coefficient exceeds 2.2, irregular shapes increase, so that fine powder due to toner crushing or the like is likely to be generated when subjected to stirring stress in a developing device or the like. Therefore, the amount of charge is likely to be reduced due to the fine powder adhering to the charging member. Furthermore, the shape factor is 1.5 to
When the number of toner particles in the range of 2.0 is at least 80% by number, the shape distribution can be made uniform, so that the effects of the present invention can be further exhibited.

[External Additives] The toner particles obtained by salting out / fusing the resin fine particles and the colorant fine particles can constitute the toner of the present invention as it is. In order to improve the cleaning property and the like, the toner of the present invention may be constituted by adding a so-called external additive to the toner particles. Such external additives are not particularly limited, and include various inorganic fine particles, organic fine particles, and lubricants.

As the inorganic fine particles that can be used as an external additive, conventionally known inorganic fine particles can be exemplified. Specifically, silica fine particles, titanium fine particles, alumina fine particles and the like can be preferably used. These inorganic fine particles are preferably hydrophobic.

Specific examples of the silica fine particles include commercially available products R-805, R-976, and R-980 manufactured by Nippon Aerosil Co., Ltd.
974, R-972, R-812, R-809, HVK-2150 and H-200 manufactured by Hoechst Co., Ltd., and commercial products TS-720, TS-530, TS manufactured by Cabot Co., Ltd.
-610, H-5, MS-5 and the like.

As specific examples of the titanium fine particles, for example,
Commercial products T-805 and T-60 manufactured by Nippon Aerosil Co., Ltd.
4. Commercial products MT-100S and MT-1 manufactured by Teika Co., Ltd.
00B, MT-500BS, MT-600, MT-60
0SS, JA-1, commercial product TA- manufactured by Fuji Titanium Co., Ltd.
300SI, TA-500, TAF-130, TAF-
510, TAF-510T, and commercial products IT-S, IT-OA, IT-OB, IT-OC manufactured by Idemitsu Kosan Co., Ltd.

As specific examples of the alumina fine particles, for example, commercial products RFY-C and C-C available from Nippon Aerosil Co., Ltd.
604, a commercial product TTO-55 manufactured by Ishihara Sangyo Co., Ltd., and the like.

Examples of the organic fine particles that can be used as an external additive include spherical fine particles having a number average primary particle diameter of about 10 to 2000 nm. Examples of the constituent material of the organic fine particles include polystyrene, polymethyl methacrylate, and styrene-methyl methacrylate copolymer.

Examples of the lubricant that can be used as an external additive include metal salts of higher fatty acids. Specific examples of such metal salts of higher fatty acids include metal stearate salts such as zinc stearate, aluminum stearate, copper stearate, magnesium stearate, and calcium stearate; zinc oleate, manganese oleate, iron oleate, and olein. Metal oleate such as copper oxyphosphate and magnesium oleate; metal palmitate such as zinc palmitate, copper palmitate, magnesium palmitate and calcium palmitate; metal linoleate such as zinc linoleate and calcium linoleate; ricinol And metal salts of ricinoleic acid such as zinc acid and calcium ricinoleate.

The amount of the external additive is preferably about 0.1 to 5% by weight based on the toner.

<Production Method of the Present Invention> The production method of the present invention comprises a step of obtaining resin fine particles, a step of obtaining colorant fine particles, and a step of salting out / fusing the obtained resin fine particles and colorant fine particles. And

As an example of the production method of the present invention, (1)
Emulsion polymerization step for preparing a dispersion of resin fine particles,
(2) a dispersion step for preparing a dispersion of colorant fine particles, (3) a salting out / fusion step of salting out / fusing resin fine particles and colorant fine particles to obtain toner particles, and (4) a toner. A filtration / washing step of filtering the toner particles from the particle dispersion and removing a surfactant or the like from the toner particles;
(5) a drying step of drying the washed toner particles;
(6) It comprises a step of adding an external additive to the dried toner particles.

Hereinafter, each step will be described. [Emulsion polymerization step] In this emulsion polymerization step, a conventionally known emulsion polymerization method can be basically used. As an example of the emulsion polymerization method, a radical polymerization initiator is dissolved in an aqueous medium (aqueous solution of a surfactant) and heated, and when a predetermined temperature (polymerization temperature) is reached, a radical polymerizable monomer (monomer) is obtained. The mixture is heated under stirring, usually under a nitrogen atmosphere. Here, in the monomer mixture, at least one of a radical polymerizable monomer having an acidic group and a radical polymerizable monomer having a basic group is contained in a ratio of 0.1 to 20% by weight. Is preferred. The polymerization temperature and the polymerization time can be appropriately set within a range where the emulsion polymerization reaction occurs. When using a chain transfer agent to adjust the molecular weight of the resin,
It is preferable to add the chain transfer agent by mixing with the radical polymerizable monomer.

As a method for obtaining composite resin fine particles composed of a core (particles) made of a high molecular weight resin and a shell made of a low molecular weight resin as the resin fine particles, an emulsion polymerization method (first stage) is used. After forming a polymerization initiator and a monomer mixture (a polymerizable monomer for obtaining a low molecular weight resin) to a dispersion of the resin fine particles (i), A method (two-stage polymerization method) of forming a shell (ii) composed of a polymer of a monomer mixture on the surface of the resin fine particles (i) by subjecting this system to an emulsion polymerization treatment (second stage). be able to. The “shell” constituting the composite resin fine particles may be not only one layer but also two or more layers. In this case, the outermost layer is preferably made of a low molecular weight resin.

[Step of Dispersing Colorant Fine Particles] In the step of dispersing the colorant fine particles, the surfactant is contained by a stirring device provided with a screen for partitioning the stirring chamber and a rotor 2 rotating at high speed in the stirring chamber. This is a step of dispersing the colorant fine particles in an aqueous medium, specifically, “CLEARMIX” (M Technic Co., Ltd.)
Agglomerated particles of the colorant with a stirring device such as
This is a step of dispersing (finely dispersing) colorant fine particles having a weight average particle diameter of 30 to 300 nm in an aqueous medium to prepare a dispersion of the colorant fine particles.

As the aqueous medium in which the colorant fine particles are dispersed, there can be mentioned an aqueous solution in which a surfactant is dissolved at a concentration higher than the critical micelle concentration (CMC).
As the surfactant, the same surfactant as that used in the emulsion polymerization step can be used. Agglomerated particles of the colorant to be subjected to the dispersion step can be prepared by charging the colorant into an aqueous medium containing a surfactant and performing preliminary dispersion (coarse dispersion) with a propeller stirrer or the like. The dispersion treatment of the colorant fine particles may be performed continuously using a device as shown in FIG. 2 or batchwise using a dispersion container equipped with a stirring device as shown in FIG. May be implemented.

[Salt-out / fusion step] In this salt-out / fusion step, the resin fine particles and the colorant fine particles are subjected to salting-out / fusion (simultaneous salting-out and fusion occur). This is a step of obtaining regular (non-spherical) toner particles.

The formula: 0.2 <(Y) between the weight average particle size (X) of the resin fine particles subjected to the salting out / fusion step and the weight average particle size (Y) of the colorant fine particles. / X) <2.
0 is preferably satisfied. The value of (Y / X) is 0.2
If it is below, the colorant fine particles are too small as compared with the resin fine particles, so that the difference in the floating state of the fine particles in the aqueous medium becomes large. There is a possibility that the generation of colorant fine particles will occur. On the other hand, when the value of (Y / X) is 2.0 or more, the difference in the floating state of the fine particles in the aqueous medium is large as in the case of the small colorant particles because the colorant fine particles are large. Therefore, it is difficult to make the colorant uniform at the time of fusing, and there is a possibility that generation of free colorant fine particles is caused.

In this salting-out / fusion step, together with resin fine particles and colorant fine particles, fine particles of an internal additive such as a charge control agent and a fixability improver (the number average primary particle diameter is 10 to 5)
(Fine particles of about 00 nm) may be salted out / fused.

In order to carry out salting out / fusion of the resin fine particles and the colorant fine particles, a salting-out agent (aggregating agent) having a critical aggregation concentration or more is added to the dispersion in which the resin fine particles and the colorant fine particles are dispersed. In addition to the addition, it is necessary to heat the dispersion above the glass transition temperature (Tg) of the resin fine particles.

The preferred temperature range for salting out / fusing is (Tg + 10) to (Tg + 50 ° C.), and particularly preferably (Tg + 15) to (Tg + 40 ° C.). Further, in order to effectively perform the fusion, it is preferable to add an organic solvent which is infinitely soluble in water to substantially lower the glass transition temperature (Tg) of the resin fine particles.

Here, examples of the “salting-out agent” used for salting-out / fusing include alkali metal salts and alkaline earth metal salts. Examples of the alkali metal constituting the salting-out agent include lithium, potassium, sodium and the like, and examples of the alkaline earth metal constituting the salting-out agent include magnesium, calcium, strontium, barium and the like. Of these, potassium, sodium, magnesium, calcium, and barium are preferred.
Examples of the counter ion (anion constituting a salt) of the alkali metal or alkaline earth metal include a chloride ion, a bromide ion, an iodide ion, a carbonate ion, and a sulfate ion.

Examples of the “organic solvent infinitely soluble in water” that can be added during salting out / fusion include methanol,
Examples include ethanol, 1-propanol, 2-propanol, ethylene glycol, glycerin, acetone and the like. Of these, alcohols having 3 or less carbon atoms, such as methanol, ethanol, 1-propanol and 2-propanol, are preferred, and 2-propanol is particularly preferred.

The temperature of the dispersion when adding the salting-out agent to the dispersion in which the resin fine particles and the colorant fine particles are dispersed is preferably not higher than the glass transition temperature (Tg) of the resin fine particles. Specifically, the temperature is preferably in the range of 5 to 55 ° C, more preferably 10 to 45 ° C. When the temperature of the dispersion at the time of adding the salting-out agent is equal to or higher than the glass transition temperature (Tg) of the resin fine particles, it is difficult to control the particle size, and large particles are easily generated.

As described above, in the salting-out / fusion step, the temperature of the dispersion liquid in which the resin fine particles and the colorant fine particles are dispersed is adjusted to the glass transition temperature (Tg) of the resin fine particles.
In the following cases, it is necessary to add a salting-out agent to the dispersion and immediately start heating the dispersion to make the temperature equal to or higher than the glass transition temperature (Tg) of the resin fine particles.

In order to carry out salting out / fusion, that is, to cause salting out and fusion simultaneously, a salting out agent is added to a dispersion in which resin fine particles and colorant fine particles are dispersed. The interval until the temperature of the dispersion reaches the temperature (the temperature at which fusing can be performed) equal to or higher than the glass transition temperature (Tg) of the resin fine particles is usually within 120 minutes, and preferably within 60 minutes. If this interval exceeds 120 minutes, agglomerated particles (non-fused particles) due to salting out
Of the toner particles, the particle size distribution of toner particles obtained by fusing the particles becomes broad, or the surface properties of the toner particles vary.

The interval between the addition of the salting-out agent to the dispersion and the start of heating the dispersion is as follows:
It is usually within 30 minutes, preferably within 15 minutes. The rate of temperature rise of the dispersion after the addition of the salting-out agent is preferably 0.25 to 5 ° C./min. If the heating rate is too low, the glass transition temperature (Tg)
It takes a long time to reach the above, and salting out and fusion cannot be performed simultaneously. On the other hand, if the heating rate is too high, it is difficult to control the particle size, and large particles are likely to be generated.

The toner particles obtained as described above are irregular (non-spherical) and have a particle diameter of 3 volume average particle diameters.
It is preferably in the range of 10 to 10 μm.

[Filtration / Washing Step] In this filtration / washing step, a filtration treatment for filtering out the toner particles from the dispersion liquid of the toner particles obtained in the above step, Washing treatment for removing extraneous substances such as surfactants and salting-out agents from the aggregates). Here, the filtration method is not particularly limited, such as a centrifugal separation method, a reduced pressure filtration method using a Nutsche method, a filtration method using a filter press, or the like.

[Drying Step] This step is a step of drying the washed toner particles. Dryers used in this step include spray dryers, vacuum freeze dryers, vacuum dryers and the like, stationary shelf dryers, mobile shelf dryers, fluidized bed dryers, rotary dryers ,
It is preferable to use a stirring dryer or the like. The moisture content of the dried toner particles is preferably 5% by weight or less, more preferably 2% by weight or less.

Incidentally, the dried toner particles are
In the case where the aggregates are aggregated by a weak attraction between particles, the aggregates may be crushed. Here, as the crushing device,
A mechanical pulverizer such as a jet mill, a Henschel mixer, a coffee mill, and a food processor can be used.

[Step of Adding External Additive] This step is a step of adding an external additive to the dried toner particles. Examples of a device used for adding the external additive include various known mixing devices such as a turbular mixer, a Hensiel mixer, a Nauter mixer, and a V-type mixer.

[Method of Adding Internal Additive] When an internal additive such as a charge control agent or a fixing property improving agent is contained in the toner particles, the method of adding the internal additive is as follows. A method of adding a dispersion of additive fine particles to a polymerization reaction system; and a step of adding a dispersion of internal additive fine particles to a dispersion of resin fine particles and colorant fine particles in a salting-out / fusing step, wherein In addition, the method of salting out / fusing the internal additive fine particles and the method of adding the internal additive fine particle dispersion to the resin fine particle dispersion are not particularly limited.

[Developer] The toner of the present invention can be used as a magnetic or non-magnetic one-component developer.
It may be used as a two-component developer by mixing with a carrier. When the toner of the present invention is used as a two-component developer, as the carrier, a conventionally known material such as iron, ferrite, a metal such as magnetite, or an alloy of such a metal with aluminum or a metal such as lead is used. be able to. Particularly, ferrite particles are preferable. The volume average particle size of the carrier is preferably from 15 to 100 μm, more preferably from 25 to 60 μm. The volume average particle size of the carrier is typically measured by a laser diffraction type particle size distribution analyzer “HELOS” equipped with a wet disperser.
(Manufactured by SYMPATEC).

Preferred carriers include a resin-coated carrier in which the surface of magnetic particles is coated with a resin, and a so-called resin-dispersed carrier in which magnetic particles are dispersed in a resin. The resin constituting the resin-coated carrier is not particularly limited, and examples thereof include an olefin resin, a styrene resin, a styrene / acrylic resin, a silicone resin, an ester resin, and a fluorine-containing polymer resin. The resin constituting the resin-dispersed carrier is not particularly limited, and a known resin can be used. For example, styrene acrylic resin, polyester resin, fluorine resin, phenol resin and the like can be used.

The developing system to which the toner of the present invention is applied is not particularly limited. It can be suitably used for both the contact developing system and the non-contact developing system. In particular, the toner of the present invention has a high charge rising property and is useful for a non-contact developing method. That is, in the non-contact developing method, since the change in the developing electric field is large, a minute change in the charge is large and acts on the development itself. For this reason, there is a large fluctuation with respect to a change in the charge amount of the toner.
However, since the toner of the present invention has a high charge rising property, the change in charge is small, and a stable charge amount can be secured. Therefore, a stable image can be formed for a long time even by the non-contact developing method.

For the contact type development, the layer thickness of the developer having the toner of the present invention is 0.1 to 8 m in the development area.
m, particularly preferably 0.4 to 5 mm. Also,
The gap between the photoconductor and the developer carrier is preferably 0.15 to 7 mm, particularly preferably 0.2 to 4 mm.

In the non-contact type developing system, the developer layer formed on the developer carrier does not come into contact with the photosensitive member. It is preferable to be formed by. In this method, a developer layer having a thickness of 20 to 500 μm is formed in a development region on the surface of the developer carrier, and a gap between the photoconductor and the developer carrier has a larger gap than the developer layer. The thin layer is formed by a magnetic blade using a magnetic force or a method of pressing a developer layer regulating rod against the surface of the developer carrier. further,
There is also a method in which a urethane blade, a phosphor bronze plate or the like is brought into contact with the surface of the developer carrier to regulate the developer layer. The pressing force of the pressing regulating member is preferably from 1 to 15 gf / mm. When the pressing force is small, the conveyance is likely to be unstable because the regulating force is insufficient. On the other hand, when the pressing force is large, the stress on the developer is increased, and the durability of the developer is likely to be reduced. A preferred range is 3 to 10 gf / mm. The gap between the developer carrier and the surface of the photoconductor needs to be larger than the developer layer. Furthermore, when a developing bias is applied during development, either a method of applying only a DC component or a method of applying an AC bias may be used. The diameter of the developer carrier is 10 to 40 m.
m is preferred. When the diameter is small, the mixing of the developer is insufficient, and it is difficult to ensure sufficient mixing to give sufficient charge to the toner. When the diameter is large, the centrifugal force on the developer becomes large. , The problem of toner scattering is likely to occur.

As the developer carrying member used in the present invention, a developing device having a magnet built in the carrying member is used, and the surface constituting the developer carrying member is aluminum, aluminum whose surface is oxidized, or aluminum. Stainless steel is used.

[0120]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Preparation of Dispersion of Colorant Fine Particles> [Preparation Example (C-1)] Sodium n-dodecyl sulfate “ADEKAHOPE LS-90” (manufactured by Asahi Denka Co., Ltd.) 0.0.90 k
g and 10.0 liters of ion-exchanged water were charged into a 20 liter resin container, and the system was stirred to prepare an aqueous solution of sodium n-dodecyl sulfate. While stirring this aqueous solution, carbon black "REGAL 330R"
1.2 kg (manufactured by Cabot) was gradually added. After the addition, the mixture was stirred for 30 minutes to preliminarily disperse the carbon black. Next, in this resin container, FIGS.
Using a stirrer "CLEARMIX" (manufactured by M Technique Co., Ltd.) as shown in (1), dispersion treatment (fine dispersion treatment) by the action of shear force generated by the screen 1 and the rotor 2 constituting the stirrer And a dispersion of colorant fine particles (hereinafter referred to as “colorant dispersion (C-1)”).
Was prepared.

Here, as the screen 1, "S1.
0-24 type "(slit width: 1.0 mm, number of slits: 24), and as rotor 2," R2 type "
It was used. In this combination, the gap (clearance) between the screen 1 and the rotor 2 is 0.5 mm. The rotation speed of the rotor 2 is 21,500 rpm (peripheral speed:
30 m / sec) and the processing time was 20 minutes (the number of CLEAR MIX passes (theoretical value) = 9).

The particle diameter of the colorant fine particles in the colorant dispersion liquid (C-1) was measured by using an electrophoretic light scattering photometer “ELS-
As a result of measurement using "800" (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle diameter was 121 nm, and the standard deviation of the particles was 12. Further, the solid content concentration of the colorant dispersion liquid (C-1) measured by a gravimetric method by standing drying was 16.6% by weight.

[Preparation Example (C-2)] Instead of carbon black "REGAL 330R", C.I. I. Preparation Example (C) except that 1.2 kg of CI Pigment Red 122 was used.
In the same manner as in -1), a dispersion of colorant fine particles (hereinafter, referred to as “colorant dispersion (C-2)”) was prepared. When the particle size of the colorant fine particles in this colorant dispersion liquid (C-2) was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle size was 105.
nm, the standard deviation of the particles was 13. Further, the solid content concentration of the colorant dispersion liquid (C-2) measured by a gravimetric method by standing drying was 16.6% by weight.

[Preparation Example (C-3)] In place of carbon black "REGAL 330R", C.I. I. Pigment Yellow 17 except that 1.2 kg of Pigment Yellow 17 was used.
In the same manner as in -1), a dispersion of colorant fine particles (hereinafter referred to as “colorant dispersion (C-3)”) was prepared. When the particle size of the colorant fine particles in the colorant dispersion liquid (C-3) was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle size was 203.
nm, the standard deviation of the particles was 8. Further, the solid content concentration of the colorant dispersion liquid (C-3) measured by a gravimetric method by standing drying was 16.6% by weight.

[Preparation Example (C-4)] Instead of carbon black "REGAL 330R", C.I. I. Pigment Blue 15.3 in the same manner as in Preparation Example (C-1) except that 1.2 kg of Pigment Blue 15.3 was used.
It is referred to as "colorant dispersion (C-4)". ) Was prepared. When the particle size of the colorant fine particles in this colorant dispersion liquid (C-4) was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle size was 9%.
3 nm, the standard deviation of the particles was 11. The solid content concentration of the colorant dispersion liquid (C-4) measured by a gravimetric method by standing drying was 16.6% by weight.

Preparation Example (C-5) Preparation Example (C-1) was the same as Preparation Example (C-1) except that 1.2 kg of carbon black “Mogal L” (manufactured by Cabot Corporation) was used instead of carbon black “Regal 330R”. Similarly, a dispersion of colorant fine particles (hereinafter referred to as “colorant dispersion (C-5)”).
Was prepared. The particle size of the colorant fine particles in the colorant dispersion liquid (C-5) was measured by using an electrophoretic light scattering photometer “ELS-8”.
As a result of measurement using "00" (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle diameter was 109 nm, and the standard deviation of the particles was 8. The solid content concentration of the colorant dispersion liquid (C-4) measured by a gravimetric method by standing drying was 16.6% by weight.

[Preparation Examples (C-6) to (C-9)] According to the following Table 1, the combination of the screen 1 and the rotor 2 and at least one of the processing conditions (the rotation speed and the processing time of the rotor 2) were changed. Except that, a dispersion of colorant fine particles (hereinafter referred to as “colorant dispersions (C-6) to (C-9)”) was prepared in the same manner as in Preparation Example (C-1). Table 1 also shows the weight average particle diameter, particle diameter distribution, and solid content of the colorant fine particles in each of the colorant dispersions (C-5) to (C-9).

[0129]

[Table 1]

[Comparative Preparation Example (c-1)] Sodium n-dodecyl sulfate “ADEKAHOPE LS-90” (manufactured by Asahi Denka Co., Ltd.) (0.0.90 kg) and 10.0 liters of ion-exchanged water in a volume of 20 liters were used. The solution was charged into a resin container, and the system was stirred to prepare an aqueous solution of sodium n-dodecyl sulfate. While stirring this aqueous solution, 1.2 kg of carbon black “REGAL 330R” (manufactured by Cabot Corporation) was gradually added. After the addition, the mixture was stirred for 1 hour to preliminarily disperse the carbon black. Next, a medium type dispersion treatment (fine dispersion treatment) is performed using a sand grinder using stainless steel particles (volume average particle diameter: 1 mm) as a medium, and a dispersion of colorant fine particles (hereinafter referred to as a “colorant dispersion for comparison”). (C-1) "). Here, the rotation speed for stirring was 8,000 rpm, and the processing time was 20 minutes. The particle size of the colorant fine particles in this comparative colorant dispersion liquid (c-1) was measured by using an electrophoretic light scattering photometer “ELS-800”.
As a result of measurement using (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle diameter was 119 nm, and the standard deviation of the particles was 41. The solid content concentration of the comparative colorant dispersion (c-1) measured by a weight method by standing drying was 16.6% by weight.

[Comparative Preparation Example (c-2)] Sodium n-dodecyl sulfate “ADEKAHOPE LS-90” (manufactured by Asahi Denka Co., Ltd.) (0.0.90 kg) and 10.0 liters of ion-exchanged water in a volume of 20 liters were used. The solution was charged into a resin container, and the system was stirred to prepare an aqueous solution of sodium n-dodecyl sulfate. While stirring this aqueous solution, 1.2 kg of carbon black “REGAL 330R” (manufactured by Cabot Corporation) was gradually added. After the addition, the mixture was stirred for 1 hour to preliminarily disperse the carbon black. Next, dispersion treatment (fine dispersion treatment) is performed using a disperser “TK homomixer” (manufactured by Tokushu Kika Kogyo Co., Ltd.) having no screen, and a dispersion of colorant fine particles (hereinafter referred to as “colorant for comparison”) Dispersion (c-2) ") was prepared. Here, the rotation speed for stirring is 1
The rotation speed was set to 2000 rpm, and the processing time was set to 30 minutes. When the particle size of the colorant fine particles in this comparative colorant dispersion liquid (c-2) was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle size was 316 nm. And the standard deviation of the particles was 42. Also,
The solid content concentration of the comparative colorant dispersion (c-2) measured by the weight method by standing drying was 16.6% by weight.

<Preparation of Aqueous Solution of Surfactant> [Preparation Example (S-1)] Sodium dodecylbenzenesulfonate which is an anionic surfactant (manufactured by Kanto Chemical Co., Ltd.)
0.55 parts by weight and 4.0 parts by weight of ion-exchanged water were charged into a stainless steel pot, and the system was stirred at room temperature to obtain an aqueous solution of an anionic surfactant (hereinafter referred to as “surfactant solution (S- 1) ") was prepared.

[Preparation Example (S-2)] Nonionic surfactant "Newcol 565C" (manufactured by Nippon Emulsifier Co., Ltd.)
14 parts by weight and 4.0 parts by weight of ion-exchanged water were charged into a stainless steel pot, and the system was stirred at room temperature to obtain an aqueous solution of a nonionic surfactant (hereinafter referred to as “surfactant solution (S-2)”). ") Was prepared.

[Preparation Example (S-3)] Nonionic surfactant "FC-170C" (manufactured by Sumitomo 3M Limited) 1.0
0 parts by weight and 1,000 parts by weight of ion-exchanged water were charged into a glass beaker, and the system was stirred at room temperature to obtain
An aqueous solution of a nonionic surfactant (hereinafter, referred to as “surfactant solution (S-3)”) was prepared.

<Preparation of Aqueous Solution of Polymerization Initiator> [Preparation Example (P-1)] 200.7 parts by weight of potassium persulfate (manufactured by Kanto Chemical Co., Ltd.) as a polymerization initiator,
2000 parts by weight were charged into an enamel pot, and this system was stirred at room temperature to prepare an aqueous solution of a polymerization initiator (hereinafter, referred to as “initiator solution (P-1)”).

[Preparation Example (P-2)] 223.8 parts by weight of potassium persulfate (manufactured by Kanto Chemical Co., Ltd.) as a polymerization initiator and 12,000 parts by weight of ion-exchanged water were charged into an enamel pot. To prepare an aqueous solution of a polymerization initiator (hereinafter, referred to as “initiator solution (P-2)”).

<Preparation of Aqueous Solution of Sodium Chloride> 5.36 parts by weight of sodium chloride (manufactured by Wako Pure Chemical Industries, Ltd.) as a salting-out agent and 20.0 parts by weight of ion-exchanged water were charged into a stainless steel pot. By stirring at room temperature, an aqueous solution of sodium chloride (hereinafter, referred to as "sodium chloride solution (N)") was prepared.

<Production of Toner Particles> [Production Example (1)] (i) Preparation of dispersion liquid of composite resin fine particles: equipped with a temperature sensor, a cooling pipe, a nitrogen introduction device, and a stirring blade, and subjected to glass lining treatment on the inner surface Then, 4.0 liters of the surfactant solution (S-1) and 4.0 liters of the surfactant solution (S-2) were charged into the prepared reaction vessel having an internal volume of 100 liters, and the system was stirred at room temperature. While adding 44.0 liters of ion-exchanged water, the system was heated. When the temperature of the system reached 70 ° C., 20.0 liters of the initiator solution (P-1) was added, and while controlling the temperature of the system to 72 ° C. ± 1 ° C.,
12.1 kg of styrene and 2.88 of n-butyl acrylate
kg, 1.04 kg of methacrylic acid and 9.02 g of t-dodecylmercaptan were added, and the mixture was stirred for 6 hours while controlling the temperature of the system at 80 ° C. ± 1 ° C. . After cooling the system to a temperature of 40 ° C. or lower, the surfactant solution (S-1) was added to the system.
4.0 liters and 4.0 liters of the surfactant solution (S-2) were added and the system was heated.

When the temperature of the system reached 70 ° C., 20.0 liters of the initiator solution (P-2) was added.
11.0 kg of styrene and 4.00 n-butyl acrylate
kg, 1.04 kg of methacrylic acid and 548 g of t-dodecylmercaptan, and the mixture was stirred for 6 hours while controlling the temperature of the system at 75 ° C ± 2 ° C. 80 ℃ ±
Stirring was performed for 12 hours while controlling at 2 ° C. The system was cooled until the temperature of the system became 40 ° C. or lower, and the stirring was stopped. By removing the scale (foreign matter) by filtration with a Paul filter, a dispersion liquid of composite resin fine particles having a high molecular weight resin as a core and a low molecular weight resin as a shell (hereinafter, referred to as “composite latex (1)”) is prepared. did. The peak molecular weight of the high molecular weight resin (core) of the composite resin fine particles constituting the composite latex (1) is 290,000, the peak molecular weight of the low molecular weight resin (shell) is 12,000, and the weight average particle diameter of the composite resin fine particles is It was 120 nm.

(Ii) Production of toner particles: The composite latex (1) was placed in a 100-liter stainless steel reaction vessel equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, a comb baffle, and a stirring blade (anchor blade). 20.0 kg, 0.4 kg of the colorant dispersion liquid (C-1), and ion-exchanged water 2
0.0 kg, and the system was stirred at room temperature. The temperature of the system was raised to 40 ° C., and sodium chloride solution (N) 2
0.0 liter, 6.00 kg of isopropyl alcohol (manufactured by Kanto Chemical Co., Ltd.), and surfactant solution (S-3) 1.
0 liters were added in this order. After leaving the system to stand for 10 minutes, heating was started, the temperature was raised to 85 ° C. over 60 minutes, and the mixture was stirred at 85 ° C. ± 2 ° C. for 1 hour to salt out the composite resin fine particles and the colorant fine particles. / Fused to form toner particles.

After the system was cooled to a temperature of 40 ° C. or less and stirring was stopped, aggregates were removed by filtration with a filter having an aperture of 45 μm to obtain a dispersion of toner particles. Next, a wet cake (an aggregate of toner particles) was separated from the obtained dispersion by filtration under reduced pressure using a Nutsche, and this was washed with ion-exchanged water. Take out the washed wet cake from Nutsche, spread it over 5 sheets of whole paper while crushing it finely, cover it with kraft paper, and dry it with a blow dryer at 40 ° C for 100 hours to form a block. An aggregate of toner particles was obtained. Next, this aggregate is subjected to a crushing treatment with a Henschel crusher to obtain a non-spherical shape (arithmetic mean value of shape coefficient: 1.85, ratio of particles having shape coefficient of 1.5 to 2.0: 92% by number) ) Was obtained (hereinafter, referred to as “toner particles (1)”). The volume average particle diameter of the toner particles (1) thus obtained is 6.3 μm, and the weight average molecular weight of the resin constituting the toner particles (1) is 55,
000, the glass transition temperature (Tg) of the resin is 57 ° C.,
The softening point of the resin was 125 ° C.

[Production Examples (2) to (9)] Instead of the colorant dispersion (C-1), the colorant dispersions (C-2) to (C-
Non-spherical toner particles (hereinafter referred to as “toner particles (2)” to “toner particles (9)”) in the same manner as in Production Example (1) except that 0.4 kg of each of 9) was used. Manufactured. The toner particles (2) thus obtained
The weight average molecular weight of the resin constituting each of (9) is 55,
000, the glass transition temperature (Tg) of the resin is 57 ° C.,
The softening point of the resin was 125 ° C. The volume average particle size of the toner particles (2) was 6.4 μm, the arithmetic average value of the shape factor was 1.69, and the ratio of particles having a shape factor of 1.5 to 2.0 was 91% by number. The volume average particle size of the toner particles (3) was 6.8 μm, the arithmetic average value of the shape factor was 1.75, and the ratio of particles having a shape factor of 1.5 to 2.0 was 82% by number. The volume average particle diameter of the toner particles (4) is 6.3 μm, and the arithmetic average value of the shape coefficient is 1.
76, the proportion of particles having a shape factor of 1.5 to 2.0 was 93% by number. The volume average particle diameter of the toner particles (5) was 6.3 μm, the arithmetic average value of the shape coefficient was 1.73, and the ratio of particles having a shape coefficient of 1.5 to 2.0 was 92% by number. The volume average particle diameter of the toner particles (6) is 6.5 μm.
m, the arithmetic mean value of the shape factor is 1.76, and the shape factor is 1.
The ratio of particles having a particle size of 5 to 2.0 was 91% by number. Also,
The volume average particle diameter of the toner particles (7) is 6.8 μm, the arithmetic average value of the shape factor is 1.63, and the shape factor is 1.5 to 2.0.
Was 93% by number. The volume average particle size of the toner particles (8) was 6.9 μm, the arithmetic average value of the shape factor was 1.69, and the ratio of particles having a shape factor of 1.5 to 2.0 was 85% by number. The volume average particle size of the toner particles (9) is 7.1 μm, and the arithmetic average value of the shape factor is 1.
78, and the ratio of particles having a shape factor of 1.5 to 2.0 was 81% by number.

[Comparative Production Examples (1) and (2)] Instead of the colorant dispersion (C-1), a comparative colorant dispersion (c-1)
To (c-2), except that 0.4 kg of each of the toner particles was used in the same manner as in Production Example (1).
“Comparative toner particles (C1)” to “Comparative toner particles (C1)
2) ". ) Manufactured. The resin constituting each of the comparative toner particles (C1) to (C2) thus obtained has a weight average molecular weight of 55,000, a glass transition temperature (Tg) of the resin of 57 ° C., and a softening point of the resin. Is 125
° C. The volume average particle diameter of the comparative toner particles (C1) was 6.9 μm, the arithmetic average value of the shape factor was 1.76,
The ratio of particles having a shape factor of 1.5 to 2.0 was 71% by number. The volume average particle diameter of the comparative toner particles (C2) was 7.3 μm, the arithmetic average value of the shape coefficient was 1.69, and the ratio of particles having a shape coefficient of 1.5 to 2.0 was 59% by number. .

<Examples 1 to 9 and Comparative Examples 1 and 2> Toner particles (1) to (9) obtained in Production Examples (1) to (9)
And, for each of the comparative toner particles (C1) and (C2) obtained in Comparative Production Examples (1) and (2), hydrophobic silica fine particles (primary average particle diameter = 12 nm) are 1% by weight. The toners of the present invention (1) to
(9) and Comparative toners (C1) and (C2) were obtained.

Each of the toners (1) to (9) of the present invention and the comparative toners (C1) to (C2) and a resin-coated carrier in which the surface of ferrite particles is coated with a styrene acrylic resin (volume average particle diameter 45 μm) ) Were mixed at a ratio that would result in a toner concentration of 6% by weight to prepare Developers 1 to 9 of the present invention and Comparative Developers 1 and 2.

<Actual Photo Test> For each of Developers 1 to 9 and Comparative Developers 1 and 2, under normal temperature and high humidity environment (temperature 20
A fogging and image defects (black spots and white spots on a solid black image) were evaluated by performing a real test in which a copied image was formed at a temperature of 80 ° C. and a relative humidity of 80%.

Here, as the image forming apparatus, a digital copier "7050" modified machine (contact development system) manufactured by Konica Corporation was used. As the photoreceptor, a stacked organic photoreceptor was used, and a method of cleaning the transfer residual toner on the photoreceptor surface with a blade was adopted. The developing conditions were set as follows.

Photoconductor surface potential = -700 V DC bias = -500 V Dsd = 600 μm Developer layer regulation = magnetic H-Cut system Developer layer thickness = 700 μm Development sleeve diameter = 40 mm

As a fixing method, a heat roll fixing method, which is a typical contact heating method, was employed. Here, the heat roller fixing device used was an upper roller (heating roller) having a resin-coated outer peripheral surface of an iron pipe containing a heater, and a lower roller having a diameter of 30 mm having a resin-coated outer peripheral surface of a silicone rubber pipe. And a roller (pressure roller) without a cleaning mechanism. The resin that covers the upper roller and the lower roller is a tetrafluoroethylene-perfluoroalkylvinyl ether copolymer. As fixing conditions, a fixing temperature of 18
5 ° C, linear pressure 0.8kg / cm, nip width 4.3m
m and the printing linear velocity were set to 250 mm / sec. Further, as the image support (transfer paper), a paper having a continuous weight of 55 kg was used.

As an evaluation method, a character image (A4) having a pixel ratio of 5% was continuously printed 100,000 times, and a blank document and a solid black document were copied every 1,000 times.
The number of printed sheets when fogging and image defects (black spots and white spots on solid black images) occurred were measured. The results are shown in Table 2 below.

In Table 2, "the number of fogging occurrences" means that the fog density (relative reflection density on white paper) measured by a Macbeth reflection densitometer "RD-918" (manufactured by Macbeth) is 0.015 or more. Means the number of copies made when The term "number of occurrences of black spots" refers to the number of copies when two or more black spots of 0.5 mmφ or more occur on a copy image of a blank document. Further, "the number of white spots" refers to the number of copies when two or more white spots having a diameter of 0.5 mm or more occur on a copy image of a solid black document.

[0152]

[Table 2]

[0153]

The toner of the present invention and the toner obtained by the production method of the present invention (hereinafter referred to as "toner according to the present invention")
That. In (2), the colorant is reliably introduced into the toner particles, and there is no difference in the content ratio of the colorant among the toner particles. Therefore, according to the toner of the present invention, even when subjected to long-term image formation, image defects such as fog and black spots do not occur. Further, according to the toner of the present invention, image defects due to fine impurities do not occur.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a rotor rotating at high speed and a fixed screen surrounding the rotor.

FIG. 2 is a schematic view showing a continuous processing apparatus provided with a rotor and a screen.

FIG. 3 is a schematic view showing a dispersion container provided with a stirring device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Screen 2 Rotor M Stirring chamber 3 Pressurized vacuum attachment 4 Pre-dispersion liquid inlet 5 Dispersion liquid outlet 6 Temperature sensor 7 Cooling jacket 8 Cooling coil 11 Dispersion container 12 Stirring device 13 Stirring shaft

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Hirose Naohiro 2970, Ishikawacho, Hachioji-shi, Tokyo Konica Corporation (72) Inventor Makoto Kono 2970, Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H005 AA21 AB02 AB03 AB06 CA21 CA23 CB18 EA05

Claims (10)

[Claims] 1. A toner obtained by salting out / fusing at least colorant fine particles and resin fine particles, wherein the colorant fine particles are divided into a screen (1) defining a stirring chamber (M) and the stirring chamber (M). A weight average particle diameter of 30 to 30 dispersed in an aqueous medium containing a surfactant by a stirrer provided with a rotor (2) rotating at high speed in M).
A toner comprising 300 nm dispersed particles. 2. A toner obtained by salting out / fusing at least colorant fine particles and resin fine particles, wherein the colorant fine particles are divided into a screen (1) defining a stirring chamber (M) and the stirring chamber (M). M) is a dispersed particle having a weight average particle diameter of 30 to 300 nm dispersed in an aqueous medium containing a surfactant by the action of a shear force generated by the rotor (2) rotating at high speed in M). Toner. 3. A toner obtained by salting out / fusing at least colorant fine particles and resin fine particles, wherein the colorant fine particles are divided into a screen (1) defining a stirring chamber (M) and the stirring chamber (M). M) dispersed in a surfactant-containing aqueous medium by the action of shear forces, collision forces, pressure fluctuations, cavitation and potential cores caused by the rotor (2) rotating at high speed in M).
A toner characterized by being dispersed particles having a weight average particle size of 30 to 300 nm. 4. A toner obtained by salting out / fusing at least colorant fine particles and resin fine particles, wherein the colorant fine particles are dispersed by using a dispersion container provided with the stirring device according to claim 1. In a water-based medium containing a surfactant contained in a container, by ejecting a colorant downward from the stirring chamber of the stirring device, the weight average particle diameter dispersed in the water-based medium is 30 to 30
A toner comprising 0 nm dispersed particles. 5. A toner obtained by salting out / fusing at least colorant fine particles and resin fine particles, wherein the colorant fine particles are dispersed in a dispersion container provided with the stirring device according to claim 1. In a water-based medium containing a surfactant accommodated in a container, a colorant is ejected in a horizontal direction from a stirring chamber of the stirring device, so that the weight average particle diameter dispersed in the water-based medium is 30%.
A toner characterized by being dispersed particles having a size of about 300 nm. 6. An aqueous system containing a surfactant by a stirrer provided with a screen (1) for partitioning and forming a stirring chamber (M) and a rotor (2) rotating at high speed in the stirring chamber (M). A method for producing a toner, comprising a step of dispersing colorant fine particles having a weight average particle size of 30 to 300 nm in a medium, and salting out / fusing the colorant fine particles and the resin fine particles. 7. A surfactant is contained by the action of a shearing force generated by a screen (1) defining and forming a stirring chamber (M) and a rotor (2) rotating at a high speed in the stirring chamber (M). Weight average particle size in aqueous medium is 30 to 300
A method for producing a toner, comprising the steps of: dispersing colorant fine particles of nm in diameter; and salting out / fusing the colorant fine particles with the resin fine particles. 8. A shearing force, a collision force, a pressure fluctuation, a cavitation and a potential generated by a screen (1) for partitioning and forming a stirring chamber (M) and a rotor (2) rotating at a high speed in the stirring chamber (M). By the action of the core,
The weight average particle diameter is 30 in an aqueous medium containing a surfactant.
A method for producing a toner, comprising: dispersing colorant fine particles of about 300 nm in thickness, and salting out / fusing the colorant fine particles with the resin fine particles. 9. A dispersing container provided with the stirring device according to claim 6, wherein a colorant is supplied from a stirring chamber of the stirring device in an aqueous medium containing a surfactant accommodated in the dispersion container. By spraying the particles downward, thereby dispersing colorant fine particles having a weight average particle size of 30 to 300 nm in the aqueous medium, and salting out / fusing the colorant fine particles and the resin fine particles. A method for producing a toner. 10. A dispersion container provided with the stirring device according to claim 6, wherein a colorant is supplied from a stirring chamber of the stirring device in an aqueous medium containing a surfactant accommodated in the dispersion container. In a horizontal direction, thereby dispersing colorant fine particles having a weight average particle diameter of 30 to 300 nm in the aqueous medium, and salting out / fusing the colorant fine particles and the resin fine particles. A method for producing a toner.