JP2019215511A - toner - Google Patents

Abstract

To provide a toner that is excellent in transfer efficiency in forming a line image under a low transfer current condition, and prevents frequent occurrence of scattering.SOLUTION: A toner includes toner particles containing a binder resin and a colorant and an external additive; the external additive contains an external additive A having a Feret diameter of 60 nm to 200 nm; the external additive A is inorganic fine particles or organic-inorganic composite fine particles; the adhesion index of the external additive A in the toner is 0.00 to 3.00; in observation of an image obtained by performing image processing on the cross-section of the toner with a transmission electron microscope (TEM), when the penetration depth of the external additive A in which a portion of the external additive A penetrates inside the toner particle from the surface of the toner particle is b(nm), and the protrusion height of the external additive A is c(nm), the penetration depth b and protrusion height c satisfy the following relational expressions (1) and (2). (1) 60≤b+c≤200; (2) 0.15≤b/(b+c)≤0.30.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a toner used in an image forming method such as an electrophotographic method.

In recent years, with the spread of electrophotographic devices such as desktop printers, the types of paper used have been diversified.
When paper having low strength or paper containing a large amount of filler is used, a large amount of paper dust is likely to be generated during printing.
This paper dust may cause various problems in the electrophotographic process.
In particular, in the direct transfer method in which the toner image is directly transferred from the photoconductor to the paper, the photoconductor comes into direct contact with the paper, so that the paper powder easily adheres to the surface of the photoconductor.
Some paper dust adhering to the surface of the photoreceptor is collected during the cleaning process. Exert. As a result, various image defects, such as poor charging and missing dots, are likely to occur.

Furthermore, in a cleanerless system, the above-mentioned influence tends to be remarkable because paper dust is not collected in the cleaning step.
In the direct transfer method, in order to suppress the adhesion of paper dust to the surface of the photoconductor, it is effective to reduce the transfer current applied in the transfer step.

However, when the transfer current is reduced, the transfer efficiency tends to decrease. In particular, in line images such as horizontal lines and vertical lines, the transfer efficiency tends to be further reduced, and improvement is required.
Conventionally, in order to improve transfer efficiency, proposals have been made focusing on the externally added state of toner. Patent Literature 1 describes a toner that defines a state in which an external additive having a large particle diameter is embedded (invaded) in toner particles. Patent Document 2 describes a toner in which the coverage of the surface of the toner particles with the inorganic fine particles and the fixing ratio of the inorganic fine particles to the toner particles are specified.

JP 2009-036980 A JP 2002-214825 A

Patent Literatures 1 and 2 describe that transfer efficiency is improved by firmly fixing a large particle size external additive excellent in spacer function.
However, in each case, since the external additive is fixed to the toner particles by applying a strong impact force, the external additive penetrates deeply into the toner particles. If the external additive penetrates deeply into the toner particles, it is difficult to obtain a sufficient spacer function even if an external additive having a large particle diameter is used.
Therefore, there is room for improvement in order to improve the transfer efficiency when forming a line image under severer transfer conditions, specifically, low transfer current conditions, as assumed by the present inventors. Remaining.

On the other hand, an external additive having a spacer function has the effect of lowering the adhesion between toner particles, but if the adhesion is not properly adjusted, the toner of the toner image before being fixed on paper tends to scatter. .

  The present invention provides a toner that is excellent in transfer efficiency when forming a line image under a low transfer current condition, and that does not easily cause scattering.

The present invention
Toner particles containing a binder resin and a colorant, and
A toner having an external additive,
The external additive contains an external additive A having a Feret diameter a of 60 nm to 200 nm,
The external additive A is inorganic fine particles or organic-inorganic composite fine particles,
The fixation index of the external additive A in the toner is 0.00 to 3.00;
Observation of an image obtained by image-processing the cross section of the toner with a transmission electron microscope (TEM) shows that the external additive A partially penetrated into the toner particle from the surface of the toner particle. When the depth is b (nm) and the convex height is c (nm), the penetration depth b and the convex height c satisfy the following relational expressions (1) and (2). Toner.
60 ≦ b + c ≦ 200 (1)
0.15 ≦ b / (b + c) ≦ 0.30 (2)

The penetration depth b (nm) of the external additive A is defined as the external additive A in the contour of the external additive A in contact with the toner particles in the observation of an image obtained by processing the cross section. The contour line of the portion where the line segment is located is defined as a contour line X, and a line segment obtained by connecting both ends of the contour line X with a straight line is defined as a line segment Z. It means the largest one of the distance between the intersection with the line X and the line segment Z.
The convex height c (nm) of the external additive A is defined as a contour of a portion other than the contour X in the contour of the external additive A when observing an image obtained by image-processing the cross section. Assuming that Y is the largest one of the distances between the line Z and the intersection of the vertical line extending from the line Z to the outline Y and the outline Y.

  According to the present invention, it is possible to provide a toner that is excellent in transfer efficiency when a line image is formed under a low transfer current condition, and is hard to cause scattering.

It is a schematic diagram which shows the calculation method of the parameter | index, such as penetration depth of the external additive A. It is a schematic diagram which shows the example of a mixing processing apparatus. It is a schematic diagram which shows the example of a structure of the stirring member used for a mixing processing apparatus. FIG. 4 is a schematic diagram illustrating an example of a state in which an external additive A enters toner particles. It is an example of a load-displacement curve obtained by a nanoindentation method and a differential curve when the curve is differentiated by a load.

  In the present invention, the description of “XX or more and XX or less” or “XX to XX” representing a numerical range means a numerical range including a lower limit and an upper limit which are endpoints unless otherwise specified.

As described above, in the direct transfer method, it is effective to reduce the transfer current in order to suppress the adhesion of paper dust to the photoconductor. However, when the transfer current is reduced, the electrostatic force for transferring the toner image from the photoreceptor to the paper is reduced, so that the transfer efficiency is likely to be reduced. Further, the transfer efficiency is also affected by the output image. For example, a line image such as a horizontal line or a vertical line is more likely to have a disadvantageous decrease in transfer efficiency than a solid image on the entire surface. This is because the lines of electric force concentrate on the edges of the electrostatic latent image on the surface of the photoreceptor, and the toner is developed along the lines of electric force. It is. Such a phenomenon that the toner is unevenly developed is called an “edge effect”. In an image having many edges, such as a line image, the amount of toner applied to the photoconductor is increased due to the edge effect, and the electrostatic adhesion to the photoconductor is easily increased. Easy to fall. The decrease in transfer efficiency becomes remarkable in a low-temperature and low-humidity environment.

Therefore, the present inventors have conducted intensive studies to improve the transfer efficiency including not only the solid image but also the line image even under the condition where the transfer current is low.
In order to improve the transfer efficiency, it is important to control the surface structure of the toner particles. That is, it is effective to reduce the adhesive force between the photoconductor and the toner.
In order to reduce the adhesive force, it is effective to use an external additive having a large particle diameter of about 100 nm (about 60 to 200 nm) which is excellent in a spacer function and to reduce the contact area between the toner and the photoreceptor. .
However, an external additive having a large particle diameter has low fixability to toner particles, and it is difficult to exhibit a spacer function through repeated use.

As a conventional method for solving this problem, a method in which a strong impact force is applied in the external addition step to increase the fixation rate of the external additive having a large particle diameter is mainly used. According to this method, the fixing rate of the external additive having a large particle diameter can be increased, and the transfer efficiency can be improved under certain transfer conditions.
However, in the above-described conventional method, although the fixation rate of the external additive having a large particle diameter increases, the external additive easily penetrates deeply into the toner particles, and the expected spacer function may not be sufficiently obtained. Therefore, under more severe transfer conditions, it is insufficient as a method for exerting the spacer function.

  Further, since the external additive is fixed with a strong impact force, the interface between the external additive having a large particle diameter and the toner particles is largely deformed, and the toner particles are distorted. This distortion increases as the external additive penetrates deeply into the toner particles, and through repeated use, cracks and cracks are apt to occur at the above-described interface of the toner particles. Accompanying fog and the like are likely to occur.

As described above, conventionally, it has been difficult to achieve the problem of suppressing the deep penetration of the large particle size external additive into the toner particles while strongly fixing the large particle size external additive to the toner particles. .
The present inventors have found that the above problem can be solved by using a toner having the following characteristics.

That is, the toner of the present invention
Toner particles containing a binder resin and a colorant, and
A toner having an external additive,
The external additive contains an external additive A having a Feret diameter a of 60 nm to 200 nm,
The external additive A is inorganic fine particles or organic-inorganic composite fine particles,
The fixation index of the external additive A in the toner is 0.00 to 3.00;
Observation of an image obtained by performing image processing on the cross section of the toner by a transmission electron microscope (TEM) shows that the external additive A partially penetrated into the toner particle from the surface of the toner particle. The height is assumed to be b (nm), and the height of the protrusion is assumed to be c (nm). At this time, the penetration depth b and the projection height c satisfy the following relational expressions (1) and (2).
60 ≦ b + c ≦ 200 (1)
0.15 ≦ b / (b + c) ≦ 0.30 (2)

Here, the penetration depth b (nm) of the external additive A refers to the observation of an image obtained by image-processing the cross section.
A contour line of a portion of the contour line of the external additive A where the external additive A is in contact with the toner particles is referred to as a contour line X,
When a line segment obtained by connecting both ends of the contour line X with a straight line is a line segment Z,
It means the largest one of the distances between the line segment Z and the intersection of the perpendicular line drawn from the line segment Z to the contour line X and the contour line X.
Further, the convex height c (nm) of the external additive A is defined as an image obtained by observing an image obtained by image-processing the cross section.
When the outline of the portion of the external additive A other than the outline X is defined as the outline Y,
It means the largest one of the distances between the line segment Z and the intersection of the perpendicular line drawn from the line segment Z to the contour line Y and the contour line Y.

  In the present invention, by suppressing the penetration of the external additive having a large particle diameter into the toner particles deeply and at the same time, firmly fixing the toner, under severe transfer conditions, specifically, under a low transfer current condition. It has been found that transfer efficiency in forming a line image can be improved.

The toner has an external additive A as a large particle size external additive having a spacer function.
Since the external additive A needs to exhibit a spacer function and needs mechanical strength, inorganic external particles or organic-inorganic composite fine particles are used as the external additive A.

  As the particle diameter of the external additive A, the Feret diameter a is 60 nm to 200 nm. Preferably, it is 70 nm to 150 nm, more preferably, 80 nm to 120 nm. Here, the Feret diameter a (nm) of the external additive A means the maximum diameter of the external additive A in observing the cross section of the toner particles with a transmission electron microscope (TEM). The above-mentioned particle diameter is suitable for the external additive A as an external additive having a large particle diameter that exerts a spacer function.

Further, the fixation index of the external additive A in the toner is 0.00 to 3.00, preferably 0.10 to 2.50, and more preferably 0.50 to 2.00.
In order to reliably exert the spacer function of the external additive A, the external additive A needs to be firmly fixed to the toner particles. If the adhesion of the external additive A is weak, the external additive A is displaced when the toner particles come into contact with each other, or the external additive A migrates from the surface of the toner particles to another member through repeated use. The spacer function may be lost, and the spacer function cannot be sufficiently exhibited. When the fixation index of the external additive A is 0.00 to 3.00, a sufficient spacer function is exhibited through repeated use.
As an index of the state of fixation of the external additive A to the toner particles, the fixation index of the external additive A is used.

The method for calculating the fixation index of the external additive A is as follows.
First, when the toner is brought into contact with the substrate and pressed with a constant force, the amount of the external additive A transferred to the substrate is calculated using image analysis. The amount of the external additive A transferred to the substrate is represented by the area ratio [A] of the external additive on the substrate. If the external additive A is strongly fixed to the toner particles, the external additive A does not migrate to the substrate even when the toner is brought into contact with the substrate, so that the area ratio [A] of the external additive A becomes a small value.

On the other hand, since the area ratio [A] of the external additive A depends on the amount of the external additive A existing on the surface of the toner particles, it is necessary to standardize the area ratio [A] in order to obtain an index. In the present invention, the coverage [B] of the toner particles with the external additive A is determined in advance by observation, and the area ratio [A] of the external additive A on the substrate is determined.
The fixation index of the external additive A was calculated from the following formula from the coverage ratio [B] of the external additive A.
Adhesion index of external additive A = area ratio of external additive A on substrate [A] / coverage of external additive A [B] × 100
The smaller the fixing index of the external additive A, the stronger the external additive A is fixed to the toner particles.
Detailed conditions will be described later.

Further, the toner is characterized in that the external additive A having a large particle diameter is firmly fixed as described above, and at the same time, deep penetration into the toner particles is suppressed.
The state in which the external additive A has penetrated the toner particles is defined by observing an image obtained by performing image processing on the toner cross section with a transmission electron microscope (TEM). Specifically, an image obtained by performing image processing on the cross section of the toner containing the external additive A is obtained using a transmission electron microscope (TEM). FIG. 1 is a schematic diagram showing a method of calculating an index such as the penetration depth of the external additive A.

In the processed image, the penetration depth of the external additive A in which a part of the external additive A has penetrated from the surface of the toner particle into the toner particle is set to b (nm), and the convex height is set to c (nm). And
The sum b + c (nm) of the penetration depth b (nm) and the convex height c (nm) is a value related to the Feret diameter a (nm) of the external additive A. In the present invention, b + c (nm) is from 60 nm to 200 nm, preferably from 70 nm to 150 nm, and more preferably from 80 nm to 120 nm.

When the ratio of the penetration depth b to the sum b + c of the penetration depth b and the projection height c of the external additive A is large, it indicates that the external additive A has penetrated deeper into the toner particles. In the present invention, the ratio (b / (b + c)) of the ratio of the penetration depth b of the external additive A to the sum b + c of the penetration depth b and the convex height c is applied to the toner particles of the external additive A. As an indicator of the intrusion of
That is, the larger the value of b / (b + c), the deeper the external additive A penetrates into the toner particles.

  The sum b + c (nm) of the penetration depth b and the convex height c of the external additive A is set to 60 nm to 200 nm, and b / (b + c) is set to 0.30 or less (preferably 0.28 or less, more preferably 0. 26 or less), a sufficient spacer function can be exhibited. However, if the value of b / (b + c) is too small, the external additive A easily migrates to other members through repeated use even if the fixation index is small, so that b / (b + c) is 0.15 or more. Yes, preferably 0.18 or more, more preferably 0.20 or more. The numerical ranges can be arbitrarily combined.

  The degree of penetration of the external additive A from the surface of the toner particle into the interior of the toner particle is set to 0. 0 while the external additive A is firmly fixed to the toner particles (fixation index: 0.00 to 3.00). Control is performed so as to satisfy 15 ≦ b / (b + c) ≦ 0.30. By doing so, it becomes possible to stably maintain the spacer function of the external additive A through repeated use. As a result, it is possible to achieve an improvement in transfer efficiency under more severe transfer conditions, which could not be achieved by the conventional technology. The value of b / (b + c) can be adjusted by appropriately changing various conditions in the method of fixing the external additive A to the toner particles. Details will be described later.

  Further, attention was paid to the shape of the external additive A fixed to the surface of the toner particles. When the external additive A satisfies the above relational expressions (1) and (2) and is fixed to the toner particles, the external additive A and the toner particles form a neck portion as shown in FIG. There are many. By forming the neck portion, the toner particles can be easily caught in a state where the adhesion between the toner particles is low.

  As a result, a loose network is formed between the toner particles in the toner image formed on the electrostatic latent image, and it is possible to make the toner less likely to scatter from the toner image in the developing step and the transfer step.

  As described above, the toner satisfying the above formulas (1) and (2) has excellent transfer efficiency when forming a line image under a low transfer current condition, and can provide a toner in which scattering does not easily occur.

The external additive A is inorganic fine particles or organic-inorganic composite fine particles.
Examples of the inorganic fine particles include fine particles such as silica fine particles, alumina fine particles, titania fine particles, and composite oxide fine particles thereof.

As a method for producing silica fine particles, for example,
A combustion method obtained by burning a silane compound (that is, a method for producing fumed silica),
The deflagration method obtained by burning metal silicon powder explosively,
A wet method obtained by a neutralization reaction between sodium silicate and a mineral acid (inorganic acid),
Sol-gel method obtained by hydrolysis of alkoxysilane such as hydrocarbyloxysilane (so-called Stoeber method)
And the like.

Further, it is preferable to use the inorganic fine particles by controlling the degree of hydrophobicity by a hydrophobic treatment.
As a method of hydrophobizing the inorganic fine particles, a method of treating the inorganic fine particles with a hydrophobizing agent is preferable.

Examples of the organic-inorganic composite fine particles include fine particles of an organic-inorganic composite material composed of an inorganic material and an organic material.
The organic-inorganic composite fine particles have good durability and chargeability as an inorganic material, and at the time of fixing, the organic material having a small heat capacity does not hinder the melting and coalescence of toner particles, so that the fixing property is improved. Is difficult to inhibit.

  As the organic-inorganic composite fine particles, organic-inorganic composite fine particles obtained by embedding inorganic fine particles on the surface of resin fine particles (preferably vinyl-based resin fine particles) as an organic material are preferable. More preferably, it is an organic-inorganic composite fine particle having a structure in which inorganic fine particles are exposed on the surface of vinyl resin particles. More preferably, it is an organic-inorganic composite fine particle having a convex portion derived from an inorganic fine particle on the surface of a vinyl-based resin particle.

Further, it is preferable that the external additive A is subjected to a hydrophobizing treatment with a hydrophobizing agent.
As the hydrophobizing agent, for example,
Chlorosilanes such as methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, t-butyldimethylchlorosilane, vinyltrichlorosilane and the like;
Tetramethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, o-methylphenyltrimethoxysilane, p-methylphenyltrimethoxysilane, n-butyltrimethoxysilane, i-butyltrimethoxy Silane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, i-butyltrisilane Ethoxysilane, decyltriethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-
Glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, alkoxysilanes such as γ- (2-aminoethyl) aminopropyltrimethoxysilane and γ- (2-aminoethyl) aminopropylmethyldimethoxysilane;
Hexamethyldisilazane, hexaethyldisilazane, hexapropyldisilazane, hexabutyldisilazane, hexapentyldisilazane, hexahexyldisilazane, hexacyclohexyldisilazane, hexaphenyldisilazane, divinyltetramethyldisilazane, dimethyltetravinyl Silazane such as disilazane;
Dimethyl silicone oil, methyl hydrogen silicone oil, methyl phenyl silicone oil, alkyl-modified silicone oil, chloroalkyl-modified silicone oil, chlorophenyl-modified silicone oil, fatty acid-modified silicone oil, polyether-modified silicone oil, alkoxy-modified silicone oil, carbinol-modified Silicone oils such as silicone oil, amino-modified silicone oil, fluorine-modified silicone oil, and terminal-reactive silicone oil;
Examples include siloxanes such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, hexamethyldisiloxane, and octamethyltrisiloxane.

  Examples of the hydrophobizing agent include undecylic acid, lauric acid, tridecylic acid, dodecylic acid, myristic acid, palmitic acid, pentadecylic acid, stearic acid, heptadecylic acid, arachiic acid, montanic acid, oleic acid, linoleic acid, and arachidonic acid. And the like, and salts of metals such as zinc, iron, magnesium, aluminum, calcium, sodium, and lithium.

  Among these, alkoxysilanes, silazanes, and straight silicone oil are preferable because they can be easily subjected to a hydrophobic treatment. One of these hydrophobizing agents may be used alone, or two or more of them may be used in combination.

Further, b / (b + c), which is an index relating to the penetration of the external additive A into the toner particles, preferably has a standard deviation of 0.00 to 0.13, and more preferably 0.00 to 0.12. Is more preferred.
Further, the convex height c (nm) is preferably from 50.0 nm to 150.0 nm, more preferably from 50.0 nm to 120.0 nm.
The standard deviation of the convex height c is preferably 0 to 30, and more preferably 0 to 20.
By controlling the standard deviation of b / (b + c) and the standard deviation of the convex height c within the above ranges, the degree of penetration of the external additive A into the toner particles and the variation of the convex height c can be suppressed, The spacer function by the external additive A can be stably exhibited. As a result, durability and environmental stability are improved.

When the length of the line segment Z is 1 (nm), 1 / (b + c) is preferably 0.70 to 0.92, and more preferably 0.70 to 0.88.
By setting l / (b + c) to 0.70 to 0.92 while satisfying the above relational expressions (1) and (2), many external additives A form toner particles while forming an appropriate neck portion. As a result, the network between the toner particles is more stably established.

Further, the coverage of the surface of the toner particles with the external additive A, determined by observation with a scanning electron microscope and image measurement, is preferably 4.0 to 50.0 area%, and is 7.0.
More preferably, the area% is 36.0 area%. The coverage of the surface of the toner particles with the external additive A can be adjusted by changing the amount of the external additive A added and the external addition conditions.
In order to obtain the spacer function by the external additive A, the coverage is preferably 4.0% by area or more. On the other hand, if the coverage is 50.0 area% or less, the external additive A tends to be uniformly dispersed on the surface of the toner particles, and the state of fixation to the toner particles tends to be uniform.

As a method of fixing the external additive A to the toner particles, a method of fixing the external additive A by heat using the mixing apparatus shown in FIGS. 2 and 3 is preferable.
As a method of firmly fixing a large particle size external additive to toner particles, a main method which has been conventionally performed is a method in which a toner and a stirring blade and a toner and a toner are mixed in a mixing device. This is a method to increase the impact force and shear force.

However, as described above, in the fixing method using a strong impact force or shear force, a large particle size external additive penetrates deeply into the toner particles, an interface between the large particle size external additive and the toner particles, It is easy to cause distortion inside.
In order to firmly fix the external additive A to the toner particles without causing the external additive A to penetrate deeply into the surface of the toner particles, the present inventors have proposed a conventional method of fixing the external additive A to a strong impact force or shear force. We thought that an external addition method based on a new idea was necessary instead of a method, and focused on fixing by heat.

When heat near the glass transition temperature (Tg) of the toner particles is applied to the toner, the surface of the toner particles is partially softened, and the external additive A can be fixed.
Further, if heat can be applied to the toner with as little impact or shearing force as possible, the fixing state of the present invention can be achieved.

On the other hand, the impact force and the shearing force of the external additive device also have the effect of uniformly dispersing the external additive on the surface of the toner particles. That is, it is preferable to uniformly disperse the external additive A on the surface of the toner particles without applying an impact force or a shearing force as much as possible.
As an example, there is a method of heating an object to be processed using the mixing apparatus shown in FIGS. 2 and 3. Thereby, the fixing index and the degree of penetration of the external additive A can be controlled, and the uniform dispersibility of the external additive A on the surface of the toner particles can be secured.

FIG. 2 is a schematic diagram illustrating an example of the mixing apparatus.
FIG. 3 is a schematic diagram showing an example of a configuration of a stirring member used in the mixing apparatus shown in FIG.

The mixing apparatus shown in FIG. 2 includes a rotating body 32 having a plurality of stirring members 33 provided on the surface thereof, a driving unit 38 for driving the rotating body to rotate, and a main body casing provided with a gap with the stirring member 33. 31.
In the gap (clearance) between the inner peripheral portion of the main body casing 31 and the stirring member 33, heat is efficiently applied to the toner particles, the toner particles are uniformly imparted, and the external additive is converted from the secondary particles to the primary particles. The external additive can be adhered to the surface of the toner particles while loosening.
Further, as will be described later, the toner particles and the external additive are easily circulated in the axial direction of the rotating body, so that the external additive is likely to be sufficiently uniformly mixed before the fixation to the toner particles proceeds.

  In this mixing apparatus, the diameter of the inner peripheral portion of the main body casing 31 is twice or less the diameter of the outer peripheral portion of the rotating body 32. FIG. 2 shows an example in which the diameter of the inner peripheral portion of the main body casing 31 is 1.7 times the diameter of the outer peripheral portion of the rotating body 32 (the diameter of the body portion excluding the stirring member 33 from the rotating body 32). I have. If the diameter of the inner peripheral portion of the main body casing 31 is not more than twice the diameter of the outer peripheral portion of the rotating body 32, the processing space in which the force acts on the toner particles is appropriately limited, so that the secondary particles become secondary particles. The external additives can be sufficiently dispersed.

  The clearance is preferably adjusted according to the size of the main body casing. The size of the clearance is preferably set to 1% to 5% of the diameter of the inner peripheral portion of the main casing 31 in that heat is efficiently applied to the toner particles. Specifically, when the diameter of the inner peripheral part of the main casing 31 is about 130 mm, the clearance is set to about 2 mm to 5 mm, and when the diameter of the inner peripheral part of the main casing 31 is about 800 mm, the clearance is about 10 mm to 30 mm. do it.

  As shown in FIG. 3, at least a part of the plurality of stirring members 33 is formed as a feeding stirring member 33 a that sends the toner particles in one direction in the axial direction of the rotating body as the rotating body 32 rotates. . At least a part of the plurality of agitating members 33 is formed as a return agitating member 33b that returns the toner particles in the other direction of the axis of the rotator as the rotator 32 rotates. Here, as shown in FIG. 2, when the material inlet 35 and the product outlet 36 are provided at both ends of the main casing 31, the direction from the material inlet 35 to the product outlet 36 (see FIG. 2). The right direction) is referred to as the “feed direction”.

That is, as shown in FIG. 3, the plate surface of the feed stirring member 33a is inclined so as to feed the toner particles in the feed direction 43. On the other hand, the plate surface of the stirring member 33b is inclined so as to send the toner particles in the return direction 42.
Thus, the heating process is performed while repeatedly performing the feeding in the feeding direction 43 and the feeding in the return direction 42. The stirring members 33a and 33b are a set of a plurality of members arranged at intervals in the circumferential direction of the rotating body 32. In the example shown in FIG. 3, the agitating members 33a and 33b form a set of two members at an interval of 180 degrees from each other on the rotating body 32, but three members at an interval of 120 ° or an interval of 90 °. A large number of members, such as four, may be combined.

In the example of the stirring member shown in FIG. 3, a total of 12 stirring members 33a and 33b are formed at equal intervals.
In FIG. 3, D indicates the width of the stirring member, and d indicates the interval indicating the overlapping portion of the stirring member. From the viewpoint of efficiently sending the toner particles in the feed direction and the return direction, D is preferably about 20% to 30% with respect to the length of the rotating body 32. FIG. 3 shows an example in which D with respect to the length of the rotating body 32 is 23%. The stirrer 33a and the stirrer 33b preferably have, to some extent, an overlapping portion d of the stirrer 33b and the stirrer 33a when an extended line is drawn in a vertical direction from an end position of the stirrer 33a.

  Thereby, the external additive can be efficiently dispersed on the surface of the toner particles. D ((d / D) × 100) with respect to D is preferably 10% to 30% in terms of applying an appropriate share.

  Regarding the shape of the blade, the toner particles can be sent in the feed direction and the return direction other than the shape shown in FIG. As long as the clearance can be maintained, for example, a shape having a curved surface or a shape of a paddle structure in which a tip blade portion is connected to the rotating body 32 by a rod-shaped arm may be used.

The mixing apparatus shown in FIG. 2 further includes a jacket 34 inside the main casing 31 and adjacent to the rotating body end side surface 310 through which the cooling medium can flow.
Further, the mixing apparatus shown in FIG. 2 further has a raw material inlet 35 formed at an upper part of the main casing 31 and a product outlet 36 formed at a lower part of the main casing 31. The raw material inlet 35 is used for introducing toner particles and external additives. The product discharge port 36 is used to discharge the mixed (externally added) toner from the main casing 31 to the outside.

  In the mixing apparatus shown in FIG. 2, a raw material input port inner piece 316 is inserted into a raw material input port 35, and a product discharge port inner piece 317 is inserted into a product discharge port 36. .

First, the raw material inlet inner piece 316 is taken out from the raw material inlet 35, toner particles and external additives are charged into the processing space 39 from the raw material inlet 35, and the raw material inlet inner piece 316 is inserted. Next, the rotator 32 is rotated by the drive unit 38 (41 indicates the direction of rotation), and the toner particles and external additives that have been input are stirred by the plurality of stirring members 33 provided on the surface of the rotator 32 to mix. While warming and mixing.
By using the above-mentioned mixing apparatus having excellent diffusion ability, the external additive can be loosened from the secondary particles to the primary particles with the minimum necessary impact force and shearing force. As a result, the external additive can be uniformly dispersed on the surface of the toner particles.
Further, warming is performed by passing warm water of an appropriate temperature through the jacket 34. The temperature of the hot water is monitored with a thermocouple installed inside the raw material inlet inner piece 316.

In order to stably obtain the toner, the thermocouple temperature (T1) of the inner piece 316 for the material input port is preferably T2-10 ° C. to T2 + 10 ° C., where T2 is the glass transition temperature of the toner particles. . More preferably, the temperature is T2-10 ° C to T2 + 5 ° C.
When T1 is equal to or higher than T2-10 ° C., the surface of the toner particles is likely to be softened, the external additive is easily fixed, and transfer of the external additive to another member due to repeated use is suppressed.
If T1 is equal to or lower than T2 + 10 ° C., the glass transition temperature of the toner particles does not greatly exceed, so that the fusion hardly occurs inside the processing apparatus. Further, it is difficult for the external additive to penetrate into the toner particles, and the spacer function by the external additive is easily obtained sufficiently.

Further, the peripheral speed V of the plurality of stirring blades of the mixing apparatus shown in FIGS. 2 and 3 is preferably 0.1 m / sec to 7.0 m / sec. Further, when the mixing energy at the time of heating and mixing is E (Wh / g), it is preferable that the following formula (3) is satisfied.
1.0 × 10 ⁻⁴ Wh / g ≦ E ≦ 1.5 × 10 ⁻² Wh / g (3)
E in the above equation (3) is the time (h) to the effective power (W) obtained by subtracting the aerodynamic power (W) operated when the toner particles are not charged from the power (W) when the toner particles are charged. And multiplied by the toner particle input amount (g).

  As described above, when the stirring blade collides with the toner particles and the external additive at high speed, the external additive penetrates deeply into the toner particle from the surface of the toner particle, and the spacer function of the external additive is impaired. A non-uniform external addition state of the additive is likely to occur. Also, residual stress accumulates at the interface between the toner particles and the external additive and inside the toner, and the toner is liable to crack due to repeated use.

By controlling the processing energies calculated from the peripheral speeds of the plurality of stirring blades, the processing power in the mixing processing apparatus, the processing time and the processing amount within the above ranges, the external additive to the toner particles can be made uniform and strong. The degree of penetration of the external additive can be appropriately controlled while achieving the fixation.
The processing time is preferably from 3 minutes to 30 minutes, more preferably from 3 minutes to 10 minutes. By controlling the processing time within the above range, it becomes easy to achieve both the strength of the toner and the appropriate fixation of the external additive.

As described above, by externally adding the external additive A while heating using the above-described mixing processing apparatus having excellent diffusivity and circulation properties, the surface of the toner particles can be reduced with the minimum necessary impact force and shear force. In addition, the external additive A can be uniformly dispersed, and a strong fixed state of the external additive A can be obtained in a short time.

  Further, the external addition process and the heating process may be simultaneously performed using the above-mentioned mixing apparatus, or the toner particles and the external additive A are mixed by a mixer such as a Henschel mixer, and the external addition process is performed. After the implementation, a heating treatment may be performed in the above-mentioned mixing apparatus.

Examples of the mixer include the following.
Mitsui Henschel mixer (Mitsui Miike Kakoki Co., Ltd.);
Super mixer (made by Kawata Corporation);
Ribocorn (Okawara Seisakusho);
Nauta mixer, turbulizer, cyclomix (manufactured by Hosokawa Micron Corporation);
Spiral pin mixer (manufactured by Taiheiyo Kiko Co., Ltd.);
Ledige Mixer (Matsubo Co., Ltd.).

  As a processing method, it is preferable that the toner particles and the external additive A are mixed by a mixer such as a Henschel mixer, the external addition is performed, and then the mixture is heated by the mixing apparatus.

The shape factor SF-2 of the external additive A measured by a scanning electron microscope (SEM) is preferably from 100 to 120, and more preferably from 110 to 120. The fact that the shape factor SF-2 is within the above range indicates that the external additive A has a structure that protrudes from the surface of the toner particles and is convex. The shape factor SF-2 can be adjusted by changing the manufacturing conditions of the external additive A.
When the external additive A having a shape factor SF-2 of 100 to 120 (more preferably 110 to 120) is used, the transfer efficiency can be improved and the fluidity of the toner can be improved. Therefore, stable charging performance can be obtained through repeated use, and fluctuation in image density can be suppressed.
The measuring method of the shape factor SF-2 will be described later.
Since the external additive A has a convex structure, the anchoring effect on the surface of the toner particles can be easily obtained, the adhesion can be easily controlled, and the resistance to the external share increases. The durability stability is improved.

In the measurement of toner strength by the nanoindentation method,
The horizontal axis is the load (mN),
When a differential curve is obtained by differentiating the load-displacement curve with the displacement amount (μm) on the vertical axis by the load,
It is preferable that the load F that becomes the maximum value of the differential curve in the load region of 0.20 mN to 2.30 mN is 0.8 mN to 2.0 mN. More preferably, it is 1.0 mN or more. Further, it is more preferably 1.5 mN or less.

  By controlling the fixed state of the external additive A as described above and increasing the mechanical strength of the toner, it is possible to suppress the toner from being cracked or crushed due to repeated use. The cracking or crushing of the toner causes poor charging and easily causes image defects such as fogging. Cracking or crushing of the toner due to repeated use becomes remarkable in a low temperature environment.

In order to obtain a high-definition image even after repeated use, it is important to control the mechanical strength of the toner.
Factors that reduce the mechanical strength of the toner are affected by the molecular weight of the binder resin and the like, but are also susceptible to distortion and stress accumulated inside the toner during the toner manufacturing process. In particular, when a strong force is applied to the toner, stress tends to accumulate inside the toner.

  The nano indentation method was adopted as an index of the strength of the toner. In the nanoindentation method, a diamond indenter is pushed into a sample placed on a stage, the load (pushing strength) and displacement (pushing depth) are measured, and mechanical properties are analyzed from the obtained load-displacement curve. This is an evaluation method.

  As a method for evaluating the mechanical properties of a toner, a fine compression tester has been often used in the past. Since the indenter used in the micro compression test is larger than the size of general toner particles, it is suitable for evaluating macroscopic mechanical properties of the toner.

  However, cracking and crushing of the toner, particularly cracking, is affected by micromechanical properties of the surface of the toner particles. Therefore, it is required to evaluate the properties in a finer area. In the measurement by the nanoindentation method, the indenter has a triangular pyramid shape, and the tip of the indenter is overwhelmingly smaller than the size of the toner particles. Therefore, it is suitable for evaluating the micro mechanical properties of the surface of the toner particles.

  In the measurement by the nanoindentation method, an extremely small load is continuously applied to the toner and the indenter is pressed into the sample, and the displacement at that time is measured. The horizontal axis is the load (mN), and the vertical axis is the displacement (μm). ), A load-displacement curve is created.

In the load-displacement curve, the toner particles are greatly deformed at a load at which the displacement with respect to the load is maximized. That is, it is considered that a phenomenon corresponding to cracking has occurred. Therefore, in the present invention, the load having the maximum slope on the load-displacement curve is defined as a load at which cracking of toner particles may occur. In other words, the larger the load at which the maximum inclination is, the greater the load required to break the toner particles, indicating that the toner particles are less likely to break.
As a method of calculating the load having the maximum slope, a method in which, in a differential curve obtained by differentiating the load-displacement curve by the load, the load having the maximum differential value as the maximum slope was employed.

In order to increase the mechanical strength of the toner, for example, it is effective to increase the molecular weight of the binder resin used for the toner particles.
In order to improve the mechanical strength of the toner without excessively increasing the molecular weight, it is preferable to provide a heating step after the external addition step. This makes it possible to alleviate the residual stress generated in the toner manufacturing process and promote the fixation of the external additive A by heat.

  The method of fixing the external additive A by heat using the mixing processing apparatus shown in FIGS. 2 and 3 is not only easy to control the fixing rate and the degree of penetration of the external additive A, but also the toner It is preferable because the strength is easily controlled.

As the binder resin used for the toner particles, for example,
Vinyl resin, styrene resin, styrene copolymer resin, polyester resin, polyol resin, polyvinyl chloride resin, phenol resin, natural resin modified phenol resin, natural resin modified maleic resin, acrylic resin, methacryl resin, polyvinyl acetate , A silicone resin, a polyurethane resin, a polyamide resin, a furan resin, an epoxy resin, a xylene resin, a polyvinyl butyral, a terpene resin, a coumarone indene resin, and a petroleum resin.
Among these, a styrene copolymer resin, a polyester resin, a mixture of a polyester resin and a vinyl resin, and a hybrid resin in which a polyester resin and a vinyl resin partially react with each other are preferable.
As the binder resin, one type may be used alone, or two or more types may be used in combination.

The toner particles may contain a release agent.
As the release agent, for example,
Waxes mainly containing fatty acid esters such as carnauba wax and montanic acid ester wax;
Fatty acid esters such as deoxidized carnauba wax, in which some or all of the acid components are deacidified;
A methyl ester compound having a hydroxyl group, obtained by hydrogenation of a vegetable oil or the like;
Saturated fatty acid monoesters such as stearyl stearate and behenyl behenate;
A diester of a saturated aliphatic dicarboxylic acid and a saturated aliphatic alcohol such as dibehenyl sebacate, distearyl dodecane diate, distearyl octadecane diate;
Aliphatic hydrocarbons such as diesters of saturated aliphatic diols and saturated fatty acids such as nonanediol dibehenate and dodecanediol distearate, low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, paraffin wax and Fischer-Tropsch wax wax;
Oxides of aliphatic hydrocarbon waxes such as oxidized polyethylene wax or block copolymers thereof;
Waxes obtained by grafting an aliphatic hydrocarbon wax with a vinyl monomer such as styrene or acrylic acid;
Saturated linear fatty acids such as palmitic acid, stearic acid and montanic acid;
Unsaturated fatty acids such as brassic acid, eleostearic acid, parinaric acid;
Saturated alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnaubayl alcohol, ceryl alcohol, and melisyl alcohol;
Polyhydric alcohols such as sorbitol;
Fatty acid amides such as linoleic acid amide, oleic acid amide, lauric acid amide;
Saturated fatty acid bisamides such as methylenebisstearic acid amide, ethylenebiscapric acid amide, ethylenebislauric acid amide, hexamethylenebisstearic acid amide; ethylenebisoleic acid amide, hexamethylenebisoleic acid amide, N, N'-dioxide Unsaturated fatty acid amides such as rail adipamide and N, N'-dioleyl sebacamide;
aromatic bisamides such as m-xylene bisstearic acid amide and N, N'-distearyl isophthalic acid amide;
Aliphatic metal salts such as calcium stearate, calcium laurate, zinc stearate and magnesium stearate (commonly referred to as metal soaps);
A long-chain alkyl alcohol or a long-chain alkyl carboxylic acid having 12 or more carbon atoms;
And the like.
Among these release agents, monofunctional or bifunctional ester waxes such as saturated fatty acid monoesters and diesters, and hydrocarbon waxes such as paraffin wax and Fischer-Tropsch wax are preferred.
One type of release agent may be used alone, or two or more types may be used in combination.

  Further, the melting point of the release agent defined by the peak temperature of the maximum endothermic peak at the time of temperature rise measured by a differential scanning calorimeter (DSC) is preferably from 60 ° C to 140 ° C. More preferably, it is 60 ° C to 90 ° C. When the melting point is 60 ° C. or higher, the storage stability of the toner is improved. On the other hand, when the melting point is 140 ° C. or less, the low-temperature fixability is easily improved.

  The content of the release agent in the toner particles is preferably 3 parts by mass to 30 parts by mass with respect to 100 parts by mass of the binder resin in the toner particles. When the content of the release agent is 3 parts by mass or more, the fixing property is easily improved. On the other hand, when the content of the release agent is 30 parts by mass or less, deterioration of the toner hardly occurs during long-term use, and image stability is easily improved.

The toner preferably contains a charge control agent.
As the charge control agent for negative charge, an organic metal complex compound and a chelate compound are preferable, and examples thereof include a monoazo metal complex compound; an acetylacetone metal complex compound; and a metal complex compound of an aromatic hydroxycarboxylic acid or an aromatic dicarboxylic acid. .
Specific examples of commercially available charge control agents include, for example,
Spiron Black TRH, T-77, T-95 (Hodogaya Chemical Industry Co., Ltd.), BONTRON S-34, S-44, S-54, E-84, E-88, E-89 (Orient Chemical ( stock))
And the like.
As the charge control agent, one type may be used alone, or two or more types may be used in combination.

  From the viewpoint of the charge amount of the toner, the content of the charge control agent in the toner particles is preferably 0.1 parts by mass to 10.0 parts by mass with respect to 100 parts by mass of the binder resin in the toner particles. More preferably, the amount is 0.1 parts by mass to 5.0 parts by mass.

The toner can be used as any toner such as a magnetic one-component toner, a non-magnetic one-component toner, and a toner for a non-magnetic two-component developer.
When the toner is used as a magnetic one-component toner, a magnetic material is preferably used as the colorant.

Examples of the magnetic material used for the magnetic one-component toner include, for example,
A magnetic iron oxide such as magnetite, maghemite, ferrite, or a magnetic iron oxide further containing other metal oxides;
Metals such as Fe, Co, Ni, or these metals and Al, Co, Cu, Pb, Mg, Ni, Sn, Zn, Sb, Be, Bi, Cd, Ca, Mn, Se, Ti, W, And alloys with metals such as V, and mixtures thereof.
Among these magnetic materials, magnetite is preferable. Examples of the shape of the magnetite include polyhedron, octahedron, hexahedron, sphere, needle, and scale. Among these shapes, those having little anisotropy such as polyhedron, octahedron, hexahedron, and sphere are preferable in terms of increasing image density.

  The volume average particle diameter of the magnetic material is preferably from 0.10 μm to 0.40 μm. When the volume average particle size is 0.10 μm or more, the magnetic material is less likely to aggregate, and the uniform dispersion of the magnetic material in the toner particles is improved. When the volume average particle size is 0.40 μm or less, the coloring power of the toner is improved.

  The volume average particle diameter of the magnetic substance can be measured using a transmission electron microscope. Specifically, after the toner particles to be observed are sufficiently dispersed in the epoxy resin, the particles are cured in an atmosphere at a temperature of 40 ° C. for two days to obtain a cured product. The obtained cured product is used as a flaky sample by a microtome, and the particle size of 100 magnetic substances in the visual field is measured with a transmission electron microscope (TEM) at a magnification of 10,000 to 40,000 times. Then, the volume average particle diameter is calculated based on the equivalent diameter of a circle equal to the projected area of the magnetic body. Further, it is also possible to measure the volume average particle diameter of the magnetic substance by an image analyzer.

  The content of the magnetic substance in the toner particles is preferably from 30 parts by mass to 120 parts by mass, more preferably from 40 parts by mass to 110 parts by mass, based on 100 parts by mass of the binder resin in the toner particles. .

  The magnetic material used for the toner can be manufactured, for example, by the following method.

  An alkali such as sodium hydroxide is added to the aqueous ferrous salt solution in an amount equivalent to or more than the iron component to prepare an aqueous solution containing ferrous hydroxide. Air is blown in while maintaining the pH of the prepared aqueous solution at 7 or more, and an oxidation reaction of ferrous hydroxide is performed while heating the aqueous solution to 70 ° C. or more, to first generate a seed crystal serving as a core of the magnetic substance.

  Next, an aqueous solution containing one equivalent of ferrous sulfate based on the amount of the alkali added previously is added to the slurry-like liquid containing the seed crystal. The reaction of ferrous hydroxide is advanced while blowing air while maintaining the pH of the solution at 5 to 10, and magnetic iron oxide particles are grown with the seed crystal as a core. At this time, by adjusting the pH, the reaction temperature and the stirring conditions, it is possible to control the shape and magnetic characteristics of the magnetic material. As the oxidation reaction proceeds, the pH of the liquid shifts to the acidic side, but it is preferable that the pH of the liquid does not fall below 5.

  The magnetic substance can be obtained by filtering, washing and drying the magnetic iron oxide particles thus obtained.

  When the toner is produced by a polymerization method, the surface of the magnetic substance is preferably subjected to a hydrophobic treatment. When the surface treatment is performed by a dry method, a coupling agent treatment can be performed on the surface of the magnetic material that has been washed, filtered, and dried. When performing the surface treatment in a wet manner, after the oxidation reaction is completed, the dried one is redispersed, or after the oxidation reaction is completed, the iron oxide obtained by washing and filtering is not dried. It can be redispersed in another aqueous medium and subjected to a coupling treatment.

  When performing redispersion, specifically, adding a silane coupling agent while stirring the redispersion, raising the temperature after hydrolysis, or adjusting the pH of the redispersion to an alkaline range after hydrolysis. To perform the coupling process.

  Among these, from the viewpoint of performing a uniform surface treatment, it is preferable that after the oxidation reaction is completed, the slurry is filtered, washed, dried, reslurried as it is, and subjected to the surface treatment.

  To treat the surface of the magnetic material by a wet method, that is, to treat the magnetic material with a coupling agent in an aqueous medium, first, the magnetic substance is dispersed in the aqueous medium to have a primary particle size, and does not settle or aggregate. With a stirring blade as described above. Next, an appropriate amount of a coupling agent is added to the dispersion, and the surface treatment is performed while hydrolyzing the coupling agent.Although stirring is performed at this time, using a device such as a pin mill or a line mill to prevent aggregation. It is preferable to perform a surface treatment while dispersing the particles.

  The aqueous medium is a medium containing water as a main component. For example, water itself, a medium in which a small amount of a surfactant is added to water, a medium in which a pH adjuster is added to water, a medium in which an organic solvent is added to water, and the like are exemplified.

  As the surfactant, a nonionic surfactant such as polyvinyl alcohol is preferable. The surfactant is preferably added so as to have a concentration of 0.1% by mass to 5.0% by mass in the aqueous medium.

  Examples of the pH adjusting agent include an inorganic acid such as hydrochloric acid.

  Examples of the organic solvent include alcohols and the like.

Examples of the coupling agent that can be used in the surface treatment of the magnetic material include a silane coupling agent and a titanium coupling agent. Among these, a silane coupling agent is preferable, and a silane coupling agent represented by the following formula (4) is more preferable.
R _m -Si-Y _n (4)
In the above formula (4), R represents an alkoxy group (preferably an alkoxy group having 1 to 3 carbon atoms), and m represents an integer of 1 to 3. Y represents an alkyl group (preferably an alkyl group having 2 to 20 carbon atoms), a phenyl group, a vinyl group, an epoxy group, an acryl group, or a methacryl group. m and n each independently represent an integer of 1 to 3. However, m + n = 4.

As the silane coupling agent represented by the above formula (4), for example,
Vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyl Diethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxy Silane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiethoxysilane, n-butyltrimethoxysilane, isobutyl Limethoxysilane, trimethylmethoxysilane, n-hexyltrimethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane, hydroxypropyltrimethoxysilane, n-hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane and the like.

Among these, it is preferable to use an alkyl trialkoxysilane coupling agent represented by the following formula (5) from the viewpoint of imparting high hydrophobicity to the magnetic material.
_{C p H 2p + 1 -Si- (} OC q H 2q + 1) 3 (5)
In the above formula (5), p represents an integer of 2 to 20, and q represents an integer of 1 to 3.

When p in the above formula (5) is 2 or more, the magnetic substance can be sufficiently imparted with hydrophobicity. When p is 20 or less, coalescence between magnetic substances can be suppressed. When q is 3 or less, the reactivity of the silane coupling agent is good, and sufficient hydrophobicity can be imparted to the magnetic material.
P in the above formula (5) is preferably an integer of 3 to 15, and q is preferably 1 or 2.

  When a hydrophobizing agent such as a silane coupling agent is used, it may be used alone or in combination of two or more. When two or more kinds are used in combination, they may be treated individually with the respective hydrophobizing agents or may be treated simultaneously.

  The total treatment amount of the coupling agent to be used is preferably 0.9 parts by mass to 3.0 parts by mass with respect to 100 parts by mass of the magnetic substance, and depends on the surface area of the magnetic substance, the reactivity of the coupling agent, and the like. It is preferable to adjust the amount of the treatment agent.

  Examples of the coloring agent other than the magnetic substance include the following.

  Examples of the black colorant include carbon black such as furnace black, channel black, acetylene black, thermal black, and lamp black.

  As the yellow colorant, a pigment or a dye can be used. Examples of the pigment include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 23, 62, 65, 73, 74, 81, 83, 93, 94, 95, 97, 98, 109, 110, 111, 117, 120, 127, 128, 129, 137, 138, 139, 147, 151, 154, 155, 167, 168, 173, 174, 176, 180, 181, 183, 191, C.I. I. Bat Yellow 1, 3, 20 and the like. Examples of the dye include C.I. I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162 and the like. These may be used alone or in combination of two or more.

  Pigments and dyes can be used as the cyan colorant. Examples of the pigment include C.I. I. Pigment Blue 1, 7, 15, 15; 1, 15; 2, 15; 3, 15; 4, 16, 17, 60, 62, 66, C.I. I. Bat Blue 6, C.I. I. Acid Blue 45 and the like. Examples of the dye include C.I. I. Solvent Blue 25, 36, 60, 70, 93, 95 and the like. These may be used alone or in combination of two or more.

As the magenta colorant, pigments and dyes can be used. Examples of the pigment include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 48; 2, 48; 3, 48; 4, 49, 50, 51, 52, 53, 54, 55, 57, 57; 63, 64, 68, 81, 81; 1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 144, 146, 150, 163, 166, 169, 177, 184, 185, 202, 206, 207, 209, 220, 221, 238, 254, C.I. I. Pigment Violet 19, C.I. I. Butt Red 1, 2, 10, 13, 15, 23, 29, 35 and the like. Examples of the dye include C.I. I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 52, 58, 63, 81, 82, 83, 84, 100, 109, 111, 121, 122, C.I. I. Disperse Red 9, C.I. I. Solvent Violet 8, 13, 14, 21, 27, C.I. I. Oil-soluble dyes such as Disperse Violet 1, C.I. I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, C.I. I. And basic dyes such as Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28 and the like. These may be used alone or in combination of two or more.
The content of the coloring agent other than the magnetic substance in the toner particles is preferably 0.5 parts by mass to 20 parts by mass with respect to 100 parts by mass of the binder resin in the toner particles.

The toner particles can be produced by a pulverization method, and also by a method of producing toner particles in an aqueous medium, such as a dispersion polymerization method, an association aggregation method, a solution suspension method, a suspension polymerization method, and an emulsion aggregation method. It is possible to manufacture. However, from the viewpoint of shape control, a method of producing toner particles in an aqueous medium is preferable.
Hereinafter, a method for producing toner particles by a suspension polymerization method will be described as an example of a method for producing toner particles.

In the suspension polymerization method, first, a colorant (and, if necessary, a polymerization initiator, a crosslinking agent, a charge control agent, and other additives) is uniformly dispersed in a polymerizable monomer capable of forming a binder resin. To obtain a polymerizable monomer composition. Thereafter, the obtained polymerizable monomer composition is dispersed in a continuous phase (for example, an aqueous phase) containing a dispersion stabilizer using a suitable stirrer, and the particles of the polymerizable monomer composition are dispersed. The toner particles are formed (granulated) and subjected to a polymerization reaction using a polymerization initiator to obtain toner particles.

  The toner particles produced by the suspension polymerization method (generally referred to as “polymerized toner particles”) satisfy the necessary or suitable requirements for the present invention since the shape of each toner particle is substantially spherical. The toner particles are easily obtained, and the measurement of the toner strength by the nanoindentation method can be performed with high reproducibility.

As the polymerizable monomer, for example,
Styrene-based monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, and p-ethylstyrene;
Methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, Acrylates such as phenyl acrylate;
Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, methacrylic acid Methacrylates such as dimethylaminoethyl and diethylaminoethyl methacrylate;
Other acrylonitrile, methacrylonitrile, acrylamide and the like can be mentioned. One of these polymerizable monomers may be used alone, or two or more thereof may be used in combination.

Among the above polymerizable monomers, a styrene-based monomer is used alone, or a styrene-based monomer is used in combination with another polymerizable monomer such as an acrylate or a methacrylate. Is preferred. This is because the structure of the toner particles is controlled, and the developing characteristics and durability of the toner are easily improved.
In particular, it is preferable to use at least one of alkyl acrylates and alkyl methacrylates and a styrene monomer as main components. That is, the binder resin is preferably a styrene acrylic resin. As the polymerization initiator used in the production of toner particles by the suspension polymerization method, the half-life at the time of the polymerization reaction is 0.5 hours to 30 hours. Some are preferred. Further, it is preferable to use 0.5 to 20 parts by mass based on 100 parts by mass of the polymerizable monomer. In this case, a polymer having a maximum molecular weight of 5,000 to 50,000 can be obtained, and preferable strength and appropriate melting characteristics can be imparted to the toner particles.

  From the viewpoints of fixability and mechanical strength, the peak molecular weight (Mp (T)) of the binder resin is preferably from 10,000 to 35,000, more preferably from 15,000 to 30,000.

As the polymerization initiator, for example,
2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis Azo or diazo polymerization initiators such as -4-methoxy-2,4-dimethylvaleronitrile and azobisisobutyronitrile;
Benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, t-butylperoxy 2-ethylhexanoate, t-butylperoxypivalate And peroxide-based polymerization initiators such as di (2-ethylhexyl) peroxydicarbonate and di (secondary butyl) peroxydicarbonate.
Among these, t-butyl peroxypivalate is preferred.
One of these polymerization initiators may be used alone, or two or more thereof may be used in combination.

  When producing the toner particles by the suspension polymerization method, a crosslinking agent may be used. The amount of the crosslinking agent used is preferably 0.001 to 15 parts by mass based on 100 parts by mass of the polymerizable monomer.

Examples of the crosslinking agent include compounds having two or more polymerizable double bonds, for example, aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, and the like;
Carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate and the like;
Divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide and divinyl sulfone;
A compound having three or more vinyl groups;
And the like. One of these crosslinking agents may be used alone, or two or more thereof may be used in combination.

  It is preferred that the polymerizable monomer composition contains a polar resin. In the suspension polymerization method, since toner particles are produced in an aqueous medium, a polar resin is contained, so that a layer of the polar resin can be formed on the surface of the toner particles, and toner particles having a core / shell structure can be obtained. Obtainable.

  When the toner particles have the core / shell structure, the degree of freedom in designing the core and the shell is increased. For example, by increasing the glass transition temperature of the shell, deterioration of the toner during repeated use such as deep penetration of the external additive into the toner particles can be easily suppressed. Further, by imparting a shielding effect to the shell, the composition of the shell can be easily made uniform, so that the toner can be uniformly charged.

As the polar resin, for example,
Homopolymers of styrene and its substituted products such as polystyrene and polyvinyl toluene;
Styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, Styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, Styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer Coalescence, styrene-maleic acid Polymer, a styrene - styrene copolymer and maleic acid ester copolymers;
Polymethyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyester resin, styrene-polyester copolymer, polyacrylate-polyester copolymer, polymethacrylate-polyester copolymer, polyamide resin , Epoxy resin, polyacrylic acid resin, terpene resin, phenol resin and the like.
One of these polar resins may be used alone, or two or more thereof may be used in combination.
Further, a functional group such as an amino group, a carboxy group, a hydroxy group, a sulfonic acid group, a glycidyl group, or a nitrile group may be introduced into the polymer of these polar resins.
Among these polar resins, polyester resins are preferred.

  As the polyester resin, at least one of a saturated polyester resin and an unsaturated polyester resin can be used.

  As the polyester resin, those synthesized from an alcohol component and an acid component can be used, and examples of the alcohol component and the acid component include the following.

As the dihydric alcohol component, for example,
Ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol , 2-ethyl-1,3-hexanediol, cyclohexanedimethanol, butenediol, octenediol, cyclohexenedimethanol, hydrogenated bisphenol A, bisphenol derivative represented by the following formula (A), represented by the following formula (A) Examples include a hydrogenated product of a bisphenol derivative, a diol represented by the following formula (B), and a hydrogenated product of a diol represented by the following formula (B).

  In the above formula (A), R represents an ethylene group or a propylene group, x and y are each independently an integer of 1 or more, and the average value of x + y is 2 to 10.

In the above formula (B), R ′ is —CH ₂ CH ₂ —,

  Or

を示す。

Indicates.

  As the dihydric alcohol component, an alkylene oxide adduct of bisphenol A is preferable because it has excellent charging characteristics and environmental stability and is well balanced in other electrophotographic characteristics. In the case of an alkylene oxide adduct of bisphenol A, the average number of moles of the added alkylene oxide is preferably 2 to 10 from the viewpoint of fixability and toner durability.

As the divalent acid component, for example,
Benzenedicarboxylic acid or anhydride thereof, such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride;
Alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, azelaic acid or anhydrides thereof;
Succinic acid or an anhydride thereof substituted with an alkyl or alkenyl group having 6 to 18 carbon atoms;
Examples include unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, and itaconic acid, and anhydrides thereof.

  Examples of the trivalent or higher alcohol component include glycerin, pentaerythritol, sorbit, sorbitan, and oxyalkylene ether of a novolak type phenol resin.

  Examples of the trivalent or higher acid component include trimellitic acid, pyromellitic acid, 1,2,3,4-butanetetracarboxylic acid, benzophenonetetracarboxylic acid, and anhydrides thereof.

The polyester resin is preferably a polycondensate of a carboxylic acid component containing a straight-chain aliphatic dicarboxylic acid having 6 to 12 carbon atoms in an amount of 10 mol% to 50 mol% based on all carboxylic acids, and an alcohol component. This makes it easier to lower the softening point of the polyester resin in a state where the peak molecular weight of the polyester resin is increased. Therefore, the strength of the toner can be increased while maintaining good fixing properties.
When the total of the alcohol component and the acid component of the polyester resin is 100 mol%, it is preferable that 45 mol% to 55 mol% is the alcohol component.

  The polyester resin can be manufactured using a catalyst such as a tin catalyst, an antimony catalyst, and a titanium catalyst. Among these, it is preferable to use a titanium-based catalyst.

  Further, from the viewpoints of developability, blocking resistance and durability, the number average molecular weight of the polar resin is preferably 2,500 to 25,000. The number average molecular weight can be measured by GPC.

  The acid value of the polar resin is preferably from 1.0 mgKOH / g to 15.0 mgKOH / g, and more preferably from 2.0 mgKOH / g to 10.0 mgKOH / g. By controlling the acid value within the above range, it is easy to uniformly form a shell made of a polar resin.

  The content of the polar resin in the toner particles is preferably 2 parts by mass to 20 parts by mass with respect to 100 parts by mass of the binder resin from the viewpoint of sufficiently obtaining the effect of the shell.

The aqueous medium in which the polymerizable monomer composition is dispersed preferably contains a dispersion stabilizer.
Examples of the dispersion stabilizer include a surfactant, an organic dispersant, and an inorganic dispersant. Among these, inorganic dispersants are preferred because they have dispersion stability due to their steric hindrance, so that they do not easily lose stability even when the reaction temperature is changed, are easy to wash, and do not easily adversely affect the toner. .
As the inorganic dispersant, for example,
Polyvalent metal phosphates such as tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate and hydroxyapatite;
Carbonates such as calcium carbonate and magnesium carbonate;
Inorganic salts such as calcium metasilicate, calcium sulfate and barium sulfate;
Examples include inorganic compounds such as calcium hydroxide, magnesium hydroxide, and aluminum hydroxide.
The inorganic dispersant is preferably used in an amount of 0.2 to 20 parts by mass based on 100 parts by mass of the polymerizable monomer. One type of dispersion stabilizer may be used alone, or two or more types may be used in combination. Furthermore, you may use together 0.001 mass part-0.1 mass part of surfactants. When the inorganic dispersant is used, it may be used as it is, but in order to obtain finer toner particles, the inorganic dispersant particles can be generated and used in an aqueous medium.
For example, when using tricalcium phosphate as an inorganic dispersant, an aqueous solution of sodium phosphate and an aqueous solution of calcium chloride can be mixed under high-speed stirring to produce water-insoluble calcium phosphate, and more uniform and fine dispersion can be obtained. It becomes possible. At this time, a water-soluble sodium chloride salt is produced as a by-product, but if the water-soluble salt is present in the aqueous medium, the dissolution of the polymerizable monomer in water is suppressed, and ultrafine toner particles are generated by emulsion polymerization. This is preferable because it becomes difficult to perform the process.

As the surfactant, for example,
Examples thereof include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium stearate, and potassium stearate.

In the step of polymerizing the polymerizable monomer, the polymerization temperature is preferably 40 ° C or higher, more preferably 50 ° C to 90 ° C. When the polymerization is carried out in this temperature range, the release agent to be included in the toner particles precipitates due to phase separation, so that the toner can be sufficiently encapsulated.
Thereafter, there is a cooling step of cooling from a reaction temperature of about 50 ° C. to 90 ° C. to terminate the polymerization reaction step. At this time, it is preferable to gradually cool the mixture so as to maintain the compatibility between the release agent and the binder resin.
After the polymerization of the polymerizable monomer is completed, the obtained polymer particles are filtered, washed, and dried to obtain toner particles. The toner of the present invention can be obtained by mixing an external additive with the toner particles as described above and fixing the mixture to the surface of the toner particles. Further, a classifying step may be included in the manufacturing process to cut coarse powder or fine powder contained in the toner particles.

It is preferable to use, in addition to the external additive A, another external additive B having a different particle size (for example, a smaller particle size). The use of external additives having different particle sizes makes it easier to control the chargeability and fluidity. When an external additive different from the external additive A is used in combination, it is preferable to use an external additive B having a number average particle size (D1) of less than 40 nm.
As for the external additive B, inorganic fine particles such as silica fine particles, alumina fine particles, titania fine particles, and composite oxide fine particles thereof, or organic-inorganic composite fine particles as described above for the external additive A may be used.

Further, in addition to the external additive A (and the external additive B), for example,
Lubricants such as fluororesin fine particles, zinc stearate fine particles, polyvinylidene fluoride fine particles;
Abrasives such as cerium oxide fine particles, silicon carbide fine particles, strontium titanate fine particles;
May be used as another external additive.

  Next, methods for measuring various physical properties according to the present invention will be described.

<Feret diameter (maximum diameter) of external additive (a), penetration depth of external additive A (b), convex height of external additive A (c), and index for penetration (b / (b + c)) ) Measurement method>
(1) Observation of cross section of toner by TEM After dispersing the toner in a visible light curable resin (trade name: ARONIX LCR Series D-800, manufactured by Toagosei Co., Ltd.), it is cured by irradiation with short wavelength light. Let it. The obtained cured product is cut out with an ultramicrotome equipped with a diamond knife to prepare a 250 nm flaky sample. Next, the cut sample was magnified at a magnification of 40,000 to 50,000 times using a transmission electron microscope (trade name: electron microscope JEM-2800, manufactured by JEOL Ltd.) (TEM-EDX), and the toner Obtain a cross-sectional image of the particles.
The toner to be observed is selected as follows.
First, the cross-sectional area of the toner particles is determined from the image of the cross-section of the toner particles, and the diameter (equivalent circle diameter) of a circle having an area equal to the cross-sectional area is determined. Only the image of the cross section of the toner particles whose absolute value of the difference between the circle equivalent diameter and the weight average particle diameter (D4) of the toner is within 1.0 μm is observed.

(2) Feret diameter (maximum diameter) of external additive (a), penetration depth of external additive A (b), convex height of external additive A (c), and index (b / ( b + c)) and the method of calculating the length (l) of the line segment Z from the surface of the external additive A whose external ferrite diameter (maximum diameter) (a) is 60 nm to 200 nm from the surface of the external additive to the inside of the toner particles. The TEM image obtained by cutting out the 400 nm portion is developed, and image processing is performed so that the surface (contour line) of the toner particle becomes a straight line as shown in FIG. Note that there is no intention to make a later-described contour line X a straight line.
Thereafter, the Feret diameter (maximum diameter) a (nm) of the external additive A, the penetration depth b (nm) of the external additive A, and the convex height c (nm) of the external additive A are determined.
From the values of the penetration depth b and the convex height c, an index b / (b + c) relating to the penetration of the external additive A is obtained.
Further, a contour line of a portion of the external additive A where the external additive A is in contact with the toner particles is defined as a contour X, and a line segment obtained by connecting both ends of the contour X with straight lines is defined as a line segment. A length l (nm) of the line segment Z is determined as a line segment Z.
For image processing, image processing software Image J (available from https://imagej.nih.gov/ij/) is used. The number of analysis is 100 particles of the external additive A, the average value is the value of a, b, c, l of the sample, and the standard deviation is also obtained.

<Measurement method of fixation index of external additive A>
As a method of converting the fixed state of the external additive A into an index, the transfer amount of the external additive A when the toner is brought into contact with the substrate is evaluated. In the present invention, as a material for a surface layer of the substrate, a substrate using a polycarbonate resin as a surface layer material is used as a substrate simulating a surface layer of a photoreceptor. Specifically, first, a bisphenol Z type polycarbonate resin (trade name: Iupilon Z-400, Mitsubishi Engineering-Plastics Co., Ltd., viscosity average molecular weight (Mv): 40000) is adjusted to a concentration of 10% by mass in toluene. To make a coating solution.
This coating liquid is applied to an aluminum sheet having a thickness of 50 μm using a No. 50 Meyer bar to form a coating film. Then, the coated film is dried at 100 ° C. for 10 minutes to produce a sheet having a polycarbonate resin layer (having a thickness of 10 μm) on the aluminum sheet. This sheet is held by the substrate holder. The substrate is a square with a side of about 3 mm.

  Hereinafter, the measurement process will be described by dividing the process into a process of arranging the toner on the substrate, a process of removing the toner from the substrate, and a process of quantifying the amount of the external additive A supplied to the substrate.

-Step of Arranging Toner on Substrate Toner is contained in a porous flexible material (hereinafter referred to as "toner holder"), and the toner holder is brought into contact with the substrate. A sponge (trade name: White Wiper) manufactured by Marusan Sangyo Co., Ltd. is used as the toner holder.
The toner holder is fixed to the tip of a load meter fixed to a stage that moves in a direction perpendicular to the contact surface of the substrate, so that the toner holder and the substrate can come into contact with each other while measuring the load. The contact between the toner holder and the substrate is performed by moving the stage, pressing the toner holder against the substrate until the load meter indicates 10 N, and then separating the toner holder from the substrate as one step. This step is repeated five times.

-Step of removing toner from the substrate An elastomer suction port having an inner diameter of about 5 mm connected to the tip of the nozzle of the cleaner is brought close to the substrate after contacting the toner holding member so as to be perpendicular to the toner arrangement surface, The toner attached to the substrate is removed. At this time, the toner is removed while visually checking the remaining degree. The distance between the end of the suction port and the substrate is 1 mm, the suction time is 3 seconds, and the suction pressure is 6 kPa.

-Step of quantifying the amount of the external additive supplied to the substrate. When quantifying the amount and the shape of the external additive A remaining on the substrate after removing the toner, observation and image by a scanning electron microscope are required. Use measurement.
First, platinum is sputtered on the substrate from which the toner has been removed under the conditions of a current of 20 mA and 60 seconds to obtain an observation sample.
In observation with a scanning electron microscope, an observation magnification at which the external additive A can be observed was arbitrarily selected. As a scanning electron microscope, a Hitachi ultra-high resolution field emission scanning electron microscope (trade name: S-4800, Hitachi High-Technologies Corporation) is used to observe with a reflected electron image of S-4800 (trade name). . The observation magnification is 50,000 times, the acceleration voltage is 10 kV, and the working distance is 3 mm. Under this condition, the particle size of the external additive A can be determined and observed.

In the image obtained by the observation, the external additive A has high luminance and the substrate has low luminance. Therefore, the amount of the external additive A in the visual field can be quantified by binarization. The binarization conditions are appropriately selected depending on the observation apparatus and sputtering conditions. In the present invention, Image J (available from https://imagej.nih.gov/ij/), which is image analysis software, is used for binarization. After binarization, only the external additive A having a Feret diameter a (nm) corresponding to 60 nm to 200 nm is extracted.
In Image J, the extraction can be performed by checking Area and Feret's Diameter from Set Measurement and using the function of Analyze Particle. From the results obtained with the Analyze Particle function, only the area of the external additive A having a Feret diameter a (nm) corresponding to 60 nm to 200 nm is integrated, and the result is divided by the area of the entire observation visual field, thereby obtaining the outside of the observation visual field. The area ratio of the additive A is determined. The above measurement is performed on 100 binarized images, and the average value is defined as the area ratio [A] (unit: area%) of the external additive A on the substrate.

  Next, the coverage [B] (unit: area%) of the external additive A to the toner particles is calculated.

The coverage of the external additive A is measured by observation with a scanning electron microscope and image measurement. In the observation with a scanning electron microscope, the observation magnification for observing the external additive A is the same as the magnification for observing the external additive A on the substrate. As the scanning electron microscope, the above-mentioned Hitachi ultra-high resolution field emission scanning electron microscope S-4800 (trade name) is used.
The image shooting conditions are as follows.

(1) Sample preparation A conductive paste is thinly applied to a sample stage (aluminum sample stage 15 mm x 6 mm), and toner is sprayed on the conductive paste. Further, air is blown off to remove excess toner from the sample stage and dry sufficiently. The sample stage is set on the sample holder, and the sample stage height is adjusted to 36 mm by the sample height gauge.
(2) Setting of S-4800 Observation Conditions The calculation of the coverage [B] of the external additive A is performed using an image obtained by observation of a backscattered electron image of S-4800. Since the reflected electron image has less charge-up than the secondary electron image, the coverage [B] of the external additive A can be accurately measured.
Inject the liquid nitrogen into the anti-contamination trap attached to the housing of S-4800 until it overflows, and leave it for 30 minutes. The “PC-SEM” of S-4800 is activated to perform flushing (cleaning of the FE chip as an electron source). Click the acceleration voltage display area of the control panel on the screen and press the [Flushing] button to open the flushing execution dialog. Confirm that the flushing intensity is 2 and execute. Confirm that the emission current due to flushing is 20 to 40 μA. Insert the sample holder into the sample chamber of the S-4800 housing. Press [Origin] on the control panel and move the sample holder to the observation position.
Click the acceleration voltage display section to open the HV setting dialog, and set the acceleration voltage to [0.8 kV] and the emission current to [20 μA]. In the [Basic] tab of the operation panel, set the signal selection to [SE], set the SE detector to [Upper (U)] and [+ BSE], and select [+ BSE] in the selection box to the right of [+ BSE]. L. A. 100] to set a mode for observation with a reflected electron image.
Similarly, in the [Basic] tab of the operation panel, the probe current of the electron optical system condition block is set to [Normal], the focus mode is set to [UHR], and the WD is set to [3.0 mm]. Press the [ON] button on the acceleration voltage display section of the control panel to apply the acceleration voltage.
(3) Focus Adjustment Drag the inside of the magnification display section of the control panel to set the magnification to 5000 (5k) times. The focus knob [COARSE] on the operation panel is rotated, and the aperture alignment is adjusted when the entire field of view is focused to some extent. Click [Align] on the control panel to display the alignment dialog, and select [Beam]. The STIGMA / ALIGNMENT knob (X, Y) on the operation panel is rotated to move the displayed beam to the center of the concentric circle. Next, "Aperture" is selected, and the STIGMA / ALIGNMENT knobs (X, Y) are turned one by one to stop or minimize the movement of the image. Close the aperture dialog and focus with auto focus. This operation is repeated twice more to focus.
Next, for the target toner, the magnification is set to 10000 (10k) times by dragging the inside of the magnification display section of the control panel with the midpoint of the maximum diameter adjusted to the center of the measurement screen. The focus knob [COARSE] on the operation panel is rotated, and the aperture alignment is adjusted when the focus is reached to some extent. Click [Align] on the control panel to display the alignment dialog, and select [Beam]. The STIGMA / ALIGNMENT knob (X, Y) on the operation panel is rotated to move the displayed beam to the center of the concentric circle.
Next, "Aperture" is selected, and the STIGMA / ALIGNMENT knobs (X, Y) are turned one by one to stop or minimize the movement of the image. Close the aperture dialog and focus with auto focus. Thereafter, the magnification is set to 50,000 (50k) times, the focus is adjusted by using the focus knob and the STIGMA / ALIGNMENT knob in the same manner as described above, and the focus is again adjusted by auto focus. This operation is repeated again to focus. Here, if the angle of inclination of the observation surface is large, the measurement accuracy of the coverage ratio tends to be low. And analyze.
(4) Image Storage Brightness adjustment is performed in the ABC mode, and a picture is taken and saved in a size of 640 × 480 pixels. The following analysis is performed using this image file. One photograph is taken for one toner, and an image is obtained for at least 30 particles or more of the toner.

The observed image is binarized using Image J (available from https://imagej.nih.gov/ij/) which is image analysis software. After binarization, only the external additive A having a Feret diameter a (nm) corresponding to 60 nm to 200 nm is extracted, and the coverage of the external additive A on the toner particles (unit: area%) is determined.
The above measurement is performed on 100 binarized images, and the average value of the external additive A coverage (unit: area%) is defined as the external additive A coverage [B].
From the area ratio [A] of the external additive A on the substrate and the coverage [B] of the external additive, the sticking index of the external additive A is calculated using the following equation.
Adhesion index of external additive A = area ratio of external additive A on substrate [A] / coverage of external additive A [B] × 100

<Method for measuring coverage of external additive A>
As the coverage of the external additive A on the surface of the toner particles, the value of the coverage [B] of the external additive A on the toner particles in the above-described method for measuring the fixation index of the external additive A is used (the unit is area%). .

<Method for measuring number average particle diameter and shape factor SF-2 of external additive>
The number average particle diameter and shape factor SF-2 of the external additive A and other external additives were determined by observing the external additives with a transmission electron microscope (trade name: JEM-2800, JEOL Ltd.). In the field of view magnified 200,000 times, the major diameter, perimeter and area of the primary particles of 100 external additives are calculated using image processing software. The image processing software to be used is Image-Pro Plus 5.1J (trade name) manufactured by Media Cybernetics.
The number average particle diameter is an average value of the major axes of primary particles of 100 external additives.
In addition, SF-2 is calculated for each of the primary particles of 100 external additives by the following formula, and the average value thereof is used.
SF-2 = (perimeter of particle) ² / area of particle × 100 / 4π

<Method of measuring toner strength by nanoindentation method>
The measurement of the strength of the toner by the nanoindentation method uses a measuring instrument (trade name: Picodenter HM500, manufactured by Fisher Instrument Co., Ltd.) using the nanoindentation method. The software uses WIN-HCU (trade name). As the indenter, a Vickers indenter (tip angle: 130 °) is used.
The measurement mainly includes a step of pressing the indenter at a predetermined speed until a predetermined load is obtained (hereinafter, referred to as a “pressing step”). The strength of the toner is calculated from a load-displacement curve as shown in FIG. 5 and a differential curve obtained by differentiating the curve by the load.

First, the microscope is focused on the screen of the video camera displayed on the software. In addition, a glass plate (hardness: 3600 N / mm ² ) on which Z-axis alignment described below is performed is used as an object on which focusing is performed. At this time, the objective lens is sequentially focused from 5 × to 20 × and 50 ×. Thereafter, adjustment is performed with a 50 × objective lens.
Next, an “approach parameter setting” operation is performed using the glass plate that has been focused as described above, and the Z axis of the indenter is aligned. After that, the glass plate is replaced with an acrylic plate, and an “indenter cleaning” operation is performed. The "indenter cleaning" operation is an operation of cleaning the tip of the indenter with ethanol and matching the indenter position specified on the software with the indenter position on the hardware, that is, the operation of adjusting the XY axes of the indenter. is there.

  After that, the microscope is focused on the toner to be measured instead of the slide glass to which the toner is attached. The method for attaching the toner to the slide glass is as follows.

First, the toner to be measured is attached to the tip of a cotton swab (manufactured by Johnson Corporation), and excess toner is sieved off at the edge of a bottle. Then, while pressing the swab shaft against the edge of the slide glass, the toner adhering to the swab is knocked down on the slide glass so that the toner becomes more layered.
Thereafter, the slide glass on which the toner is further adhered as described above is set on a microscope, the toner is focused on with a 50 × objective lens, and the software is set so that the tip of the indenter is at the center of the toner particles. The selected toner particles are limited to particles having a major axis and a minor axis of about D4 (μm) ± 1.0 μm of the toner.

The measurement is performed by performing the indentation process under the following conditions.
(Indentation process)
Maximum indentation load: 2.5mN
Indentation time: 100 seconds From the above measurement, a load-displacement curve is created in which the horizontal axis is the load (mN) and the vertical axis is the displacement (μm).

As a method of calculating the “load having the maximum slope” defined as the toner strength, a load having a maximum differential value in a differential curve obtained by differentiating the load-displacement curve by the load is employed. The load range for obtaining the differential curve is set to 0.20 mN to 2.30 mN in consideration of data accuracy.
The above measurement is performed for 30 toner particles, and the arithmetic mean value is adopted.
In the above measurement, every time one toner particle is measured, the above-described “indenter cleaning” operation (including the XY axis alignment of the indenter) is always performed.

<Method of measuring weight average particle size (D4)>
The weight average particle diameter (D4) of the toner and the toner particles is:
A precise particle size distribution measuring apparatus (trade name: Coulter Counter Multisizer 3, manufactured by Beckman Coulter, Inc.) using a pore electric resistance method equipped with a 100 μm aperture tube, and
Attached dedicated software for setting measurement conditions and analyzing measurement data (trade name: Beckman Coulter Multisizer3 Version 3.51, manufactured by Beckman Coulter)
Was used to measure with 25,000 effective measurement channels, and the measured data was analyzed and calculated.

  As the electrolytic aqueous solution used for the measurement, one prepared by dissolving a special grade sodium chloride in ion-exchanged water so as to have a concentration of about 1% by mass, for example, ISOTONII (trade name) manufactured by Beckman Coulter, Inc. can be used.

Before the measurement and analysis, the setting of the dedicated software was performed as follows.
In the “Change standard measurement method (SOM) screen” of the dedicated software, set the total count number in the control mode to 50,000 particles, set the number of measurements to 1, and set the Kd value to “standard particles 10.0 μm” (manufactured by Beckman Coulter, Inc.). ) Is used to set the value obtained. The threshold and the noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1600 μA, the gain is set to 2, and the electrolytic solution is set to ISOTON II (trade name), and a check is made in the flash of the aperture tube after the measurement.
On the “pulse to particle size conversion setting screen” of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.

The specific measuring method is as follows.
(1) About 200 mL of the above electrolytic solution is placed in a 250 mL round bottom beaker made of glass exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 revolutions / second. Then, the dirt and air bubbles in the aperture tube are removed by the “flash aperture tube” function of the dedicated software.
(2) About 30 mL of the above electrolytic aqueous solution is put into a glass 100 mL flat bottom beaker. Then, as a dispersant, about 0.3 mL of a diluent obtained by diluting Contaminone N (trade name) manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. with ion-exchanged water 3 times by mass is added. Contaminone N (trade name) is a 10% by mass aqueous solution of a neutral detergent for cleaning precision instruments at pH 7 consisting of a nonionic surfactant, an anionic surfactant and an organic builder.
(3) A predetermined amount of ion-exchanged water is put into a water tank of an ultrasonic disperser (trade name: Ultrasonic Dispersion System Tetora 150, manufactured by Nikkaki Bios Co., Ltd.), and contaminone N (trade name) is put in this water tank. Add about 2 mL. The Ultrasonic Dispersion System Tetora 150 is an ultrasonic disperser having an electrical output of 120 W, in which two oscillators having an oscillation frequency of 50 kHz are built in with a phase shift of 180 degrees.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid level of the aqueous electrolytic solution in the beaker is maximized.
(5) In a state where the electrolytic aqueous solution in the beaker of the above (4) is irradiated with ultrasonic waves, about 10 mg of toner is added little by little to the electrolytic aqueous solution and dispersed. Further, the ultrasonic dispersion processing is continued for 60 seconds. In the ultrasonic dispersion, the water temperature is appropriately adjusted so that the water temperature of the water tank is 10 ° C to 40 ° C.
(6) The electrolytic aqueous solution of the above (5) in which the toner is dispersed is dropped using a pipette into the round bottom beaker of the above (1) installed inside the sample stand so that the measured concentration becomes about 5%. adjust. Then, measurement is performed until the number of particles to be measured reaches 50,000.
(7) Analyze the measured data with the dedicated software attached to the device, and calculate the weight average particle size (D4). The “arithmetic diameter” on the analysis / volume statistical value (arithmetic average) screen when the graph / volume% is set by the dedicated software is the weight average particle diameter (D4).

<Method of measuring Tg of toner particles>
The Tg of the toner particles is measured by a differential scanning calorimeter (trade name: Q2000, TA Instrument)
(manufactured by U.S. U.Ments) according to ASTM D3418-82. The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of the calorific value uses the heat of fusion of indium.
Specifically, 2 mg of the sample was precisely weighed, placed in an aluminum pan, and an empty aluminum pan was used as a reference. The measurement is performed at / min. In the measurement, the temperature is once raised to 200 ° C., then lowered to 30 ° C., and then the temperature is raised again. A specific heat change is obtained in the temperature range of 40 ° C. to 100 ° C. in the second heating process. The intersection between the line at the midpoint of the baseline before and after the specific heat change and the differential heat curve at this time is defined as the glass transition temperature Tg.

<Method of measuring acid value of polyester resin>
The acid value is the number of mg of potassium hydroxide required to neutralize the acid contained in 1 g of the sample. The acid value of the amorphous polyester is measured according to JIS K0070-1992. Specifically, the acid value is measured according to the following procedure.
(1) Preparation of reagent Dissolve 1.0 g of phenolphthalein in 90 mL of ethyl alcohol (95% by volume), add ion-exchanged water to make 100 mL, and obtain a phenolphthalein solution.
Dissolve 7 g of special grade potassium hydroxide in 5 mL of water and add ethyl alcohol (95% by volume) to make 1 L. After leaving the container in an alkali-resistant container for 3 days so as not to be exposed to carbon dioxide gas, the solution is filtered to obtain a potassium hydroxide solution. The obtained potassium hydroxide solution is stored in an alkali-resistant container. The factor of the potassium hydroxide solution was as follows: 25 mL of 0.1 mol / L hydrochloric acid was placed in an Erlenmeyer flask, and a few drops of the phenolphthalein solution were added. Determined from the amount of potassium solution. As the above-mentioned 0.1 mol / L hydrochloric acid, one prepared according to JIS K8001-1998 is used.
(2) Operation (A) Main test A 2.0 g sample of the crushed amorphous polyester was precisely weighed in a 200 mL Erlenmeyer flask, and 100 mL of a mixed solution of toluene / ethanol (2: 1) was added to dissolve it for 5 hours. I do. Next, a few drops of the phenolphthalein solution are added as an indicator, and titration is performed using the potassium hydroxide solution. Note that the end point of the titration is when the light red color of the indicator continues for about 30 seconds.
(B) Blank test Titration is performed in the same manner as described above, except that no sample is used (that is, only a mixed solution of toluene / ethanol (2: 1) is used).
(3) The obtained result is substituted into the following equation to calculate an acid value.
A = [(CB) × f × 5.61] / S
Here, A is the acid value (mgKOH / g), B is the addition amount (mL) of the potassium hydroxide solution in the blank test, and C is the addition amount (mL) of the potassium hydroxide solution in the main test. ), F is the factor of the potassium hydroxide solution, and S is the mass (g) of the sample.

  Hereinafter, the present invention will be described specifically with reference to examples. The number of parts in the following formulations is based on mass unless otherwise specified.

<Production Example of External Additives A-1 to A-8>
External additives A-1 to A-8, which are organic-inorganic composite fine particles, were produced according to the description in Examples described in WO 2013/063291.
Table 1 shows the physical properties of the external additives A-1 to A-8.

<Production Example of External Additives A-9 and A-10>
A mixed gas of silicon tetrachloride, oxygen, and hydrogen was led to a burner, baked at a burner temperature of 1,100 ° C., cooled, and collected by a back filter. The obtained fumed silica fine particles are subjected to dispersion treatment in a gas phase, and 100 parts of fumed silica fine particles are sprayed with 6 parts of hexamethyldisilazane as a surface treating agent, so that coalescence of the fumed silica particles does not occur. While stirring as described above.
After the obtained reaction product was dried, it was subjected to a heat treatment at 130 ° C. for 2 hours, and adjusted to 123 nm and 78 nm by classification to obtain external additives A-9 and A-10 as silica particles.
Table 1 shows the physical properties of the external additives A-9 and A-10.

<Production Example of External Additive A-11>
After oxygen gas was supplied to the burner and the ignition burner was ignited, hydrogen gas was supplied to the burner to form a flame, into which silicon tetrachloride as a raw material was charged and gasified. A flame hydrolysis reaction was carried out under the conditions of an amount of silicon tetrachloride of 100 kg / hour, an amount of oxygen gas of 30 Nm ³ / hour, an amount of hydrogen gas of 50 Nm ³ / hour and a residence time of 0.01 second, and the generated silica powder was recovered. .
The obtained silica powder was transferred to an electric furnace, spread in a thin layer, and then subjected to a heat treatment at 750 ° C. to be sintered and agglomerated to obtain silica fine particles.
After adding hydrophobic treatment by adding 10 parts of hexamethyldisilazane as a surface treating agent to 100 parts of the obtained silica fine particles, the mixture was adjusted to 185 nm by classification, and the external additive A as silica particles was used. -11 was obtained.
Table 1 shows properties of the external additive A-11.

<Production Examples of External Additives A-12 to A-13 and External Additives -14 to -15>
In a 3 L glass reactor equipped with a stirrer, a dropping funnel and a thermometer, 687.9 g of methanol, 42.0 g of pure water and 47.1 g of 28% by mass ammonia water were put and mixed. The temperature of the resulting solution was adjusted to 35 ° C., and 1100.0 g (7.23 mol) of tetramethoxysilane and 395.2 g of 5.4 mass% aqueous ammonia were simultaneously added with stirring. Tetramethoxysilane was added dropwise over 5 hours and ammonia water over 4 hours.
After completion of the dropwise addition, the mixture was further stirred for 0.2 hours to carry out hydrolysis to obtain a dispersion of hydrophilic spherical sol-gel silica fine particles in methanol-water.

Next, an ester adapter and a condenser were attached to the glass reactor, and the dispersion was heated to 65 ° C. to distill off methanol. Thereafter, the same amount of pure water as the distilled methanol was added. This dispersion was dried at 80 ° C. under reduced pressure. The obtained silica particles were heated in a thermostat at 400 ° C. for 10 minutes. The above process was performed 20 times, and the obtained silica fine particles (untreated silica) were crushed with a pulverizer (manufactured by Hosokawa Micron Corporation).
Thereafter, 500 g of the silica particles were charged into a polytetrafluoroethylene inner cylinder stainless steel autoclave having an inner volume of 1000 mL. After the inside of the autoclave was replaced with nitrogen gas, 0.5 g of hexamethyldisilazane and 0.1 g of water were atomized by a two-fluid nozzle into silica particles while rotating the stirring blade attached to the autoclave at 400 rpm. Sprayed evenly. After stirring for 30 minutes, the autoclave was sealed and heated at 200 ° C. for 2 hours. Subsequently, deammonia was performed by reducing the pressure in the system while heating, and an external additive A-12 as silica particles was obtained.
Table 1 shows the physical properties of External Additive A-12.

Further, except that the particle size of the untreated silica used was changed and the strength of the crushing treatment was adjusted, the external additive A-13, the external additive -14 and the external additive were prepared in the same manner as the external additive A-12. Agent-15 was obtained.
Table 1 shows the physical properties of External Additive A-13, External Additive-14, and External Additive-15.

<Production Example of External Additive B-1>
A silica raw material (fumed silica particles having a primary particle number average particle size of 12 nm) was charged into an autoclave equipped with a stirrer, and heated to 200 ° C. in a fluidized state by stirring.
The inside of the reactor was replaced with nitrogen gas, the reactor was sealed, and 25 parts of hexamethyldisilazane was sprayed into 100 parts of the silica raw material, and the silane compound treatment was performed in a fluidized state of silica. After the reaction was continued for 60 minutes, the reaction was terminated. After completion of the reaction, the autoclave was depressurized and washed with a nitrogen gas stream to remove excess hexamethyldisilazane and by-products from the obtained hydrophobic silica.
Further, 10 parts of dimethyl silicone oil (viscosity: 100 mm ² / sec) was sprayed on 100 parts of the silica raw material while stirring the hydrophobic silica in the reaction tank, and stirring was continued for 30 minutes. Thereafter, the temperature was raised to 300 ° C. with stirring, and the mixture was further stirred for 2 hours. Then, it was taken out and subjected to a crushing treatment to obtain an external additive B-1 as silica particles.

<Synthesis of polyester resin>
The following components were placed in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe, and reacted at 230 ° C. for 10 hours while distilling off water generated under a nitrogen stream.
Bisphenol A ethylene oxide 2 mol adduct 350 parts Bisphenol A propylene oxide 2 mol adduct 326 parts Terephthalic acid 250 parts Titanium catalyst (titanium dihydroxybis (triethanolaminate)) 2 parts Then, under reduced pressure of 5 to 20 mmHg When the acid value became 0.1 mg KOH / g or less, the mixture was cooled to 180 ° C., 80 parts of trimellitic anhydride was added, and the mixture was reacted under a normal pressure for 2 hours, taken out, and cooled to room temperature. Thereafter, the resultant was pulverized to obtain a polyester resin. The acid value of the obtained resin was 8 mgKOH / g.

<Production example of treated magnetic material>
In the aqueous ferrous sulfate solution, 1.00 equivalent to 1.10 equivalent of sodium hydroxide solution with respect to iron atom, and P ₂ O _{5 in an} amount of 0.15 mass% in terms of phosphorus atom with respect to iron atom. were mixed amount of SiO ₂ comprised 0.50 wt% of silicon atoms in terms relative to the iron atom. Thereafter, an aqueous solution containing ferrous hydroxide was prepared. The pH of this aqueous solution was adjusted to 8.0, and an oxidation reaction was carried out at 85 ° C. while blowing air into the aqueous solution to prepare a slurry liquid having seed crystals.

Next, an aqueous ferrous sulfate solution was added to this slurry solution so that the amount thereof was 0.90 to 1.20 equivalents relative to the initial amount of alkali (the sodium component of sodium hydroxide). Thereafter, while maintaining the pH of the slurry solution at 7.6, the oxidation reaction was advanced while blowing air into the slurry solution to obtain a slurry solution containing magnetic iron oxide.
After the obtained slurry liquid was filtered and washed, the aqueous slurry was once taken out. At this time, a small amount of the water-containing slurry was sampled and the water content was measured.

Next, this water-containing slurry was put into another aqueous medium without drying, and was re-dispersed with a pin mill while stirring and circulating the slurry to adjust the pH of the re-dispersed liquid to about 4.8.
Then, 1.6 parts of the n-hexyltrimethoxysilane coupling agent was added to 100 parts of the magnetic iron oxide while stirring (the amount of the magnetic iron oxide was calculated as a value obtained by subtracting the water content from the water-containing slurry). Hydrolysis was performed. Thereafter, stirring was performed to adjust the pH of the dispersion to 8.6, and surface treatment was performed. The resulting hydrophobic magnetic material was filtered with a filter press, washed with a large amount of water, dried at 100 ° C. for 15 minutes, and then dried at 90 ° C. for 30 minutes. Thereafter, the obtained particles were crushed to obtain a treated magnetic material having a volume average particle size of 0.21 μm.

<Production Example of Toner Particle T-1>
After 450 parts of a 0.1 mol / L aqueous solution of Na ₃ PO ₄ was added to 720 parts of ion-exchanged water and heated to 60 ° C., 67.7 parts of a 1.0 mol / L aqueous solution of CaCl ₂ was added and dispersed. An aqueous medium containing the agent was obtained.

Styrene 75.0 parts N-butyl acrylate 25.0 parts Polyester resin 10.0 parts Divinylbenzene 0.6 parts Iron complex of monoazo dye (trade name: T-77, manufactured by Hodogaya Chemical Industry Co., Ltd.) 1.5 Part: treated magnetic material: 65.0 parts The above materials were uniformly dispersed and mixed using an attritor (Mitsui Miike Kakoki Co., Ltd.) to obtain a polymerizable monomer composition. The polymerizable monomer composition was heated to 63 ° C., and 15.0 parts of paraffin wax (melting point: 78 ° C.) was added thereto, mixed and dissolved. Thereafter, 7.0 parts of a polymerization initiator tert-butyl peroxypivalate was dissolved.

The polymerizable monomer composition is charged into the aqueous medium, and stirred at 12,000 rpm for 10 minutes at 60 ° C. in a nitrogen atmosphere using a TK homomixer (Tokusai Kika Kogyo Co., Ltd.) to form particles ( Granulation).
Thereafter, the mixture was reacted at 70 ° C. for 4 hours while stirring with a paddle stirring blade. After the completion of the reaction, it was confirmed that the colored resin particles were dispersed in the aqueous medium obtained here, and that calcium phosphate as an inorganic dispersant was attached to the surface of the colored resin particles.

Next, the temperature of the aqueous medium in which the colored resin particles were dispersed was raised to 100 ° C. and maintained for 120 minutes. Thereafter, the mixture is cooled to room temperature at 3 ° C. per minute, hydrochloric acid is added to dissolve the dispersant, filtered, washed with water, and dried to obtain toner particles T-1 having a weight average particle diameter (D4) of 8.0 μm. Obtained.
Table 2 shows the physical properties of the obtained toner particles T-1.

<Production Example of Toner Particles T-2 to T-5>
In the production of the toner particles 1, as described in Table 2, the toner particles T-2 to T-5 were produced in the same manner as in the production example of the toner particles T-1, except that the amount of the polymerization initiator was changed. Was manufactured.
Table 2 shows the physical properties of T-2 to T-5 of the obtained toner particles.

<Production Example of Toner Particle T-6>
715 parts of ion-exchanged water and 750 parts of a 0.1 mol / L Na ₃ PO ₄ aqueous solution were added to a four-necked container, and a high-speed stirring apparatus T.P. K. The mixture was maintained at 60 ° C. while stirring at 12000 rpm using a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.). 68 parts of a 1.0 mol / L CaCl ₂ aqueous solution was gradually added thereto to prepare an aqueous dispersion medium containing a fine hardly water-soluble dispersion stabilizer Ca ₃ (PO ₄ ) ₂ .

Styrene 125 parts n-butyl acrylate 35 parts Copper phthalocyanine pigment (Pigment Blue 15: 3) 15 parts Polyester resin (condensation polymer of terephthalic acid and 2 mol of propylene oxide adduct of bisphenol A (terephthalic acid: propylene of bisphenol A) Oxide 2 mol adduct = 51: 50 (molar ratio)), acid value: 10 mgKOH / g, glass transition point: 70 ° C., Mw: 10500, Mw / Mn: 3.30) 10 parts Load control agent (3) , 5-Di-tert-butylsalicylic acid aluminum compound)
0.9 parts wax (Fischer-Tropsch wax, endothermic main peak temperature: 78 ° C)
13 parts The above materials were stirred for 3 hours using an attritor (manufactured by Nippon Coke Industry Co., Ltd.), and each component was dispersed in a polymerizable monomer to prepare a monomer mixture. To this monomer mixture was added 20.0 parts of 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (a 50% by mass toluene solution) as a polymerization initiator, and the polymerization was continued. A monomer composition was prepared.
The polymerizable monomer composition was charged into an aqueous dispersion medium, and granulated for 5 minutes while maintaining the rotation speed of the stirrer at 10,000 rpm. After that, the high-speed stirring device was changed to a propeller-type stirrer, the internal temperature was raised to 70 ° C., and the reaction was carried out for 6 hours while stirring slowly.

Next, the temperature inside the vessel was raised to 80 ° C. and maintained for 4 hours, and then gradually cooled to 30 ° C. at a cooling rate of 1 ° C. per minute to obtain a slurry. Dilute hydrochloric acid was added to the container containing the slurry to remove the dispersion stabilizer. Further, the resultant was separated by filtration, washed and dried to obtain toner particles T-6 having a weight average particle diameter (D4) of 8.0 μm.
Table 2 shows the physical properties of the obtained toner particles T-6.

<Production Example of Toner Particle T-7>
(Preparation of each dispersion)
[Resin particle dispersion (1)]
Styrene (manufactured by Fujifilm Wako Pure Chemical Co., Ltd.) 325 parts n-butyl acrylate (manufactured by Fujifilm Wako Pure Chemical Co., Ltd.) 100 parts Acrylic acid (manufactured by Rhodia Nikka Co., Ltd.) 13 parts 1,10-decanediol Diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) 1.5 parts Dodecanethiol (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.) 3 parts The above materials are mixed in advance, dissolved to prepare a solution, and then anionic. A surfactant solution obtained by dissolving 9 parts of a surfactant (trade name: Dowfax A211, manufactured by Dow Chemical Company) in 580 parts of ion-exchanged water was placed in a flask. 400 parts of the above solution was added and dispersed, emulsified, slowly stirred for 10 minutes, and mixed with 50 parts of ion-exchanged water in which 6 parts of ammonium persulfate was dissolved.
Next, after the inside of the flask was replaced with nitrogen, the flask was heated to 75 ° C. in an oil bath with stirring, and emulsion polymerization was continued for 5 hours to obtain a resin particle dispersion liquid (1).
The resin particles were separated from the resin particle dispersion (1) and the physical properties were examined. The number average particle diameter was 195 nm, the solid content in the dispersion was 42%, the glass transition temperature was 51.5 ° C., and the weight average molecular weight ( Mw) was 32,000.

[Resin particle dispersion (2)]
The amorphous polyester was subjected to a dispersion treatment using a disperser obtained by modifying Cavitron CD1010 (trade name) manufactured by Eurotech Co., Ltd. into a high-temperature and high-pressure type. Specifically, first, 79% by mass of ion-exchanged water, 1% by mass (as an active ingredient) of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK), and 20% by mass of the above-mentioned amorphous polyester The pH was adjusted to 8.5 with ammonia at the composition ratio described above. The Cavitron was operated under the conditions that the rotation speed of the rotor was 60 Hz, the pressure was 5 kg / cm ² , and the temperature was heated to 140 ° C. by the heat exchanger. A resin fine particle dispersion (2) having a number average particle size of 200 nm was obtained.

(Colorant dispersion)
Carbon black 20 parts Anionic surfactant (trade name: Neogen R, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 2 parts Ion-exchanged water 78 parts A homogenizer (trade name: Ultra Turrax T50, manufactured by IKA) The pigment was soaked in water at 3000 rpm for 2 minutes, and further subjected to a dispersion treatment at 5,000 rpm for 10 minutes, followed by defoaming by stirring with an ordinary stirrer for 24 hours. Thereafter, the mixture was dispersed for about 1 hour at a pressure of 240 MPa using a high-pressure impact dispersing machine Ultimateizer (trade name: HJP30006, manufactured by Sugino Machine Co., Ltd.) to obtain a colorant dispersion. Further, the pH of the dispersion was adjusted to 6.5.

(Releasing agent dispersion)
Hydrocarbon wax (Fischer-Tropsch wax, peak temperature of maximum endothermic peak: 78 ° C., weight average molecular weight: 750) 45 parts Cationic surfactant (trade name: Neogen RK, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 5 parts 200 parts of ion-exchanged water The above material was heated to 95 ° C. and dispersed by a homogenizer (trade name: Ultra Turrax T50, manufactured by IKA), and then dispersed by a pressure discharge type Gaulin homogenizer to obtain a number average diameter of 190 nm. Thus, a release agent dispersion having a solid content of 25% was obtained.

(Production example of toner particles)
Ion-exchanged water 400 parts Resin particle dispersion (1) (resin particle concentration: 42% by mass) 620 parts Resin particle dispersion (2) (resin particle concentration: 20% by mass) 279 parts Anionic surfactant (product) Name: Neogen RK, Daiichi Kogyo Seiyaku Co., Ltd., ratio of active ingredient: 60% by mass) 1.5 parts (0.9 parts as active ingredient)
The above material was placed in a 3 L reaction vessel equipped with a thermometer, a pH meter and a stirrer, and kept at a temperature of 30 ° C. and a stirring rotation speed of 150 rpm for 30 minutes while controlling the temperature from the outside with a mantle heater.
Thereafter, 88 parts of the colorant dispersion liquid and 60 parts of the release agent dispersion liquid were charged and held for 5 minutes. As it was, a 1.0% aqueous nitric acid solution was added to adjust the pH to 3.0.

  Then the stirrer and mantle heater were removed. Then, a dispersion solution of 0.33 parts of polyaluminum chloride and 37.5 parts of a 0.1% nitric acid aqueous solution was dispersed in a homogenizer (trade name: Ultra Tarax T50, manufactured by IKA Japan) at 3000 rpm while dispersing the mixture. One-half of that was added. Thereafter, the dispersion rotation speed was set to 5000 rpm, and the remaining 1/2 was added over 1 minute, and the dispersion rotation speed was set to 6500 rpm, and the dispersion treatment was performed for 6 minutes.

A stirrer and a mantle heater were installed in the reaction vessel, and while appropriately adjusting the rotation speed of the stirrer so that the slurry was sufficiently stirred, the temperature was raised to 42 ° C at a rate of 0.5 ° C / min. Hold for 15 minutes. Thereafter, the particle size was measured with a Coulter Multisizer every 10 minutes while heating at a rate of 0.05 ° C./min, and when the weight average particle size became 7.8 μm, a 5% aqueous sodium hydroxide solution was added. To bring the pH to 9.0.
Thereafter, the temperature was raised to 96 ° C. at a rate of 1 ° C./min while adjusting the pH to 9.0 every 5 ° C., and maintained at 96 ° C. for 3 hours. Thereafter, the temperature was lowered to 20 ° C. at 1 ° C./min to solidify the particles.

Thereafter, the reaction product was filtered, washed by passing water through ion-exchanged water, and when the conductivity of the filtrate became 50 mS or less, the caked particles were taken out and placed in ion-exchanged water having a volume 10 times the particle mass. I put it in. Thereafter, the mixture was stirred by a three-one motor, and when the particles were sufficiently loosened, the pH was adjusted to 3.8 with a 1.0% nitric acid aqueous solution, and the mixture was maintained for 10 minutes.
Thereafter, the solution was filtered again, washed with flowing water, and when the conductivity of the filtrate became 10 mS or less, the flowing of water was stopped, and solid-liquid separation was performed.

The obtained cake-like particles were crushed by a sample mill and dried in an oven at 40 ° C. for 24 hours. Further, after the obtained particles were crushed by a sample mill, additional vacuum drying was performed in an oven at 40 ° C. for 5 hours to obtain toner particles T-7.
Table 2 shows the physical properties of the obtained toner particles T-7.

<Production Example of Toner Particle T-8>
(Production example of high molecular weight component)
Styrene 75.3 parts n-butyl acrylate 20.0 parts monobutyl maleate 4.7 parts divinylbenzene 0.008 parts 2,2-bis (4,4-di-t-butylperoxycyclohexyl) propane
0.150 parts The above materials were purged with nitrogen while stirring 200 parts of xylene in a four-necked flask, and the temperature was raised to 120 ° C., and then the above components were added dropwise over 4 hours. Further, the polymerization was completed under reflux of xylene, and the solvent was distilled off under reduced pressure. The resin thus obtained was used as a high molecular weight component.

(Production example of low molecular weight component)
Styrene 69.5 parts n-butyl acrylate 22.0 parts monobutyl maleate 8.5 parts di-t-butyl peroxide 1.1 parts The above materials were added dropwise to 200 parts of xylene over 4 hours. Further, the polymerization was completed under xylene reflux, and the solvent was distilled off under reduced pressure. The resin thus obtained was used as a low molecular weight component.
The high molecular weight component and the low molecular weight component obtained as described above are mixed and dissolved in a ratio of 20 parts / 80 parts of high molecular weight component / low molecular weight component to 200 parts of xylene. After heating and stirring under reflux for 12 hours, the organic solvent was distilled off, and the obtained resin was cold-rolled, solidified, and pulverized to obtain a styrene acrylic resin.

next,
Styrene acrylic resin 1 100 parts Magnetic iron oxide particles (average particle size: 0.13 m, Hc = 11.5 kA / m, σs = 88 Am ² / kg, σr = 14 Am ² / kg) 60 parts Fischer trop push wax (trade name) : C105, manufactured by Sasol, melting point: 105 ° C) 2 parts Charge control agent (trade name: T-77, manufactured by Hodogaya Chemical Industry Co., Ltd.) 2 parts The above materials were premixed with a Henschel mixer, and then biaxially extruded. Using a machine (trade name: PCM-30, manufactured by Ikegai Co., Ltd.), the temperature was set such that the melt temperature at the discharge port was 150 ° C., and the mixture was melt-kneaded.
The obtained kneaded material was cooled, coarsely pulverized by a hammer mill, and then finely pulverized using a pulverizer (trade name: Turbo Mill T250, manufactured by Freund Turbo Co., Ltd.). The resulting finely pulverized powder was classified using a multi-segment classifier utilizing the Coanda effect to obtain toner particles T-8 having a weight average particle size (D4) of 7.8 μm.
Table 2 shows the physical properties of the obtained toner particles T-8.

<Production Example of Toner 1>
Using a Mitsui Henschel mixer (FM) (Mitsui Miike Kakoki Co., Ltd.), 100 parts of toner particles T-1, 1.5 parts of external additive A-1 and 0.3 parts of external additive B-1 were used. The mixture was mixed at a speed of 35 m / sec for 100 seconds (first time). Thereafter, a heating treatment was performed using the mixing apparatus shown in FIG. 2 (second time).
As the mixing apparatus shown in FIG. 2, the one having a diameter of the inner peripheral portion of the main casing 310 of 130 mm was used. Hot water was passed through the inside of the jacket such that the temperature (T1) inside the inner piece 316 for the material inlet was 55 ° C.

After the externally added toner is charged into the mixing apparatus shown in FIG. 2 having the above configuration, the peripheral speed of the outermost end of the stirring member blade 33 (1. (0 m / sec), and heat-treated for 10 minutes.
After the completion of the heat treatment, the mixture was sieved with a mesh having an opening of 75 μm to obtain Toner 1.
Table 3 shows the physical properties of Toner 1.

<Production Examples of Toners 2 to 16>
Toners 2 to 16 were obtained in the same manner as in Production Example of Toner 1, except that the materials and production conditions shown in Table 3 were used in Production Example of Toner 1.
Table 3 shows the physical properties of Toners 2 to 16.

<Production Examples of Toners 17 and 20>
In the production example of Toner 1, the materials were changed to those shown in Table 3, and mixed with a Mitsui Henschel Mixer (FM) (Mitsui Miike Kakoki Co., Ltd.) at a peripheral speed of 46 m / sec for 10 minutes to form toners 17 and 20. Obtained.
Table 3 shows the physical properties of Toners 17 and 20.

<Production Examples of Toners 18 and 19>
In the production example of Toner 1, the materials were changed to those shown in Table 3 and mixed with Toner 1 by using a Mitsui Henschel mixer (FM) (Mitsui Miike Kakoki Co., Ltd.) at a peripheral speed of 46 m / sec for 10 minutes. Similarly, toners 18 and 19 were obtained.
The Feret diameters (maximum diameters) of the external additives 14 and 15 for the toner 18 and the toner 19 were 50 nm for the toner 18 and 220 nm for the toner 19, respectively. Was not included.

<Production Example of Toner 21>
In the production example of the toner 1, a toner 21 was obtained in the same manner as in the production example of the toner 1, except that the materials and production conditions shown in Table 3 were used.
Table 3 shows the physical properties of Toner 21.

<Example 1>
A cartridge (trade name: CF230X) for an electrophotographic laser beam printer (trade name: LaserJet Prom203dw, manufactured by Hewlett-Packard Co.) employing a cleanerless system was filled with 150 g of the toner 1, and the following evaluation was performed.

<Transfer efficiency of line image>
In a low-temperature and low-humidity environment (15 ° C./10% RH), the transfer current was adjusted to 5.0 μA, and a 4-dot / 4-space horizontal line image was output. At this time, the transfer residual toner on the surface of the photoreceptor was removed by taping with a transparent polyester adhesive tape (trade name: polyester tape No. 5511, Nichiban). The density difference was calculated by subtracting the density of the tape obtained by attaching the peeled adhesive tape on paper and the density difference of the density obtained by attaching only the adhesive tape on paper.
The transfer efficiency of the horizontal line image was evaluated at the time when one image was output, the time when 3,500 images were output, and the time when 5,000 images were output. The horizontal line image was output in an intermittent mode in which the horizontal line at which the printing rate became 1% was temporarily stopped every two sheets.
To measure the concentration, refer to REFLECT METER MODEL TC TC manufactured by Tokyo Denshoku.
It measured using -6DS (brand name). A green filter was used as a filter.
Judgment criteria are as follows. The results are shown in Table 4.
A: The density difference is less than 5.0.
B: The density difference is 5.0 or more and less than 10.0.
C: The density difference is 10.0 or more and less than 15.0.
D: The density difference is 15.0 or more.
The smaller the value of the density difference, the better.

<Evaluation of scattering>
The scattering was evaluated by visually observing the reproducibility of the line and the toner scattering around the line when a 1-dot line image that was easily dispersed was printed out in a low-temperature and low-humidity environment (15.0 ° C., 10.0% RH). did. The evaluation timing was the same as the evaluation of the transfer efficiency.
Judgment criteria are as follows. The results are shown in Table 4.
A: Almost no scattering occurs and good line reproducibility is shown.
B: Slight scattering is observed.
C: Scattering is observed, but has little effect on line reproducibility.
D: Remarkable scattering is observed, and the line reproducibility is poor.

<Image density>
The image density was determined by forming a solid black image over the entire surface in a high-temperature and high-humidity environment (32.5 ° C./80% RH), and measuring the density of the solid image with a Macbeth densitometer (manufactured by Macbeth) using an SPI filter. . The evaluation timing was the same as the evaluation of the transfer efficiency.
Judgment criteria are as follows. The results are shown in Table 4.
A: 1.45 or more B: 1.40 or more and less than 1.45 C: 1.35 or more and less than 1.40 D: less than 1.35 The higher the density value, the better.

<Fog>
The evaluation of fog was carried out using the above-described evaluator under an environment of low temperature and low humidity (15.0 ° C., 10.0% RH) where the mechanical properties of the toner became severe.
The measurement of fog was measured by using REFLECT METER MODEL TC-6DS (trade name) manufactured by Tokyo Denshoku. A green filter was used as a filter. As for fog, for the white image immediately after the solid black image was output, the surface of the photoconductor (photosensitive drum) was taped with Mylar tape, and the reflectivity of the Mylar tape pasted on the paper was compared with that of the Mylar tape pasted directly on the paper. Calculated by subtracting from Macbeth concentration. The evaluation was made according to the following criteria.
Fog (%) = Reflectance of tape directly pasted on paper (%)-Reflectance of tape taped on drum (%)
The evaluation was carried out under the same conditions as those for the first and black rear drums after passing 3,500 sheets and 5,000 sheets.
Judgment criteria are as follows. The results are shown in Table 4.
A: less than 5% B: 5% or more and less than 10% C: 10% or more and less than 20% D: 20% or more The smaller the fog value (%), the better.

<Examples 2 to 14>
The same evaluation as in Example 1 was performed on the toners shown in Table 4. The results are shown in Table 4.

<Examples 15 and 16>
In Example 1, a toner supply member was attached to a process cartridge (trade name: CF230X) for an electrophotographic laser beam printer (trade name: LaserJet Prom 203dw, manufactured by Hewlett-Packard Company). Then, the same evaluation as in Example 1 was performed except that 120 g of the toner 15 and the toner 16 were filled in the process cartridge, respectively. Table 4 shows the evaluation results.

<Example 17>
In Example 1, a cleaner member was attached to a cartridge (trade name: CF230X) for an electrophotographic laser beam printer (trade name: LaserJet Prom 203dw, manufactured by Hewlett Packard), and the same evaluation as in Example 1 was performed. The results are shown in Table 4.

<Comparative Examples 1 to 5>
The same evaluation as in Example 1 was performed on the toners shown in Table 4. The results are shown in Table 4.

  31: body casing, 32: rotating body, 33, 33a, 33b: stirring member, 34: jacket, 35: raw material inlet, 36: product outlet, 37: central axis, 38: drive unit, 39: processing space z , 310: Rotation direction, 42: Return direction, 43: Feed direction, 316: Inner piece for raw material input port, 317: Inner piece for product discharge port, d: Overlapping part of stirring member Indicated interval, D: width of stirring member

Claims (9)

Toner particles containing a binder resin and a colorant, and
A toner having an external additive,
The external additive contains an external additive A having a Feret diameter a of 60 nm to 200 nm,
The external additive A is inorganic fine particles or organic-inorganic composite fine particles,
The fixation index of the external additive A in the toner is 0.00 to 3.00;
Observation of an image obtained by image-processing the cross section of the toner with a transmission electron microscope (TEM) shows that the external additive A partially penetrated into the toner particle from the surface of the toner particle. When the depth is b (nm) and the convex height is c (nm), the penetration depth b and the convex height c satisfy the following relational expressions (1) and (2). ,toner.
60 ≦ b + c ≦ 200 (1)
0.15 ≦ b / (b + c) ≦ 0.30 (2)
(The penetration depth b (nm) of the external additive A means the external additive A in the contour of the external additive A in contact with the toner particles in the image obtained by image-processing the cross section. Is defined as a contour line X, and a line segment obtained by connecting both ends of the contour line X with a straight line is referred to as a line segment Z, a perpendicular line from the line segment Z to the contour line X is defined as The distance between the intersection with the contour line X and the line segment Z means the largest distance, and the convex height c (nm) of the external additive A means observation of an image obtained by image-processing the cross section. In a case where a contour of a portion other than the contour X among the contours of the external additive A is defined as a contour Y, a vertical line descending from the line Z to the contour Y and the contour Y It means the largest of the distances between the intersection and the line segment Z.)   2. The toner according to claim 1, wherein a coverage of the toner particles with the external additive A is 4.0 area% to 50.0 area%.   3. The toner according to claim 1, wherein the shape factor SF-2 of the external additive A measured by a scanning electron microscope (SEM) is 100 to 120. 4.   In the measurement of the strength of the toner by the nano-indentation method, when a load-displacement curve in which the horizontal axis is a load (mN) and the vertical axis is a displacement (μm) is obtained, a differential curve obtained by differentiating the load with a load is obtained. 4. The toner according to claim 1, wherein a load F at which the differential curve has a maximum value in a load range of 20 mN to 2.30 mN is 0.8 mN to 2.0 mN. 5.   The toner according to any one of claims 1 to 4, wherein the standard deviation of b / (b + c) is 0.00 to 0.13.   The toner according to claim 1, wherein the convex height c is 50.0 nm to 150.0 nm.   The toner according to any one of claims 1 to 6, wherein a standard deviation of the convex height (c) is 0 to 30.   The toner according to any one of claims 1 to 7, wherein 1 / (b + c) is 0.70 to 0.92 when the length of the line segment Z is 1 (nm).   The toner according to any one of claims 1 to 8, wherein the fixation index of the external additive A in the toner is 0.10 to 2.50.

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