JP2002351142A - Electrostatic charge image developing toner and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide electrostatic charge image developing toners which do not give rise to a change in a charge holding function and are free of density unevenness even after lapse of a long-term use stoppage period at and under a high temperature and high humidity without being affected by the remaining materials existing on toner particle surfaces and are used to form color images having particularly beautiful transparency and excellent color differences. SOLUTION: The electrostatic charge image developing toners are toners having an island-and-sea structure containing at least a resin and coloring agents and the average value of the areas of the polygonal shapes formed by perpendicular bisectors between the center of gravity of the islands adjacent to each other in the island-and-sea structure is 20,000 to 120,000 nm<2> and the coefficient of fluctuation in the areas of the polygonal shapes is <=25%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic image used in a copying machine, a printer, and the like, a method for producing the toner, and an image forming method using the toner.

[0002]

2. Description of the Related Art In recent years, a polymerized toner obtained by a suspension polymerization method or an emulsion polymerization method has a small particle size and uniform distribution in order to control the particle size and shape of the toner in a polymerization process in an aqueous medium. Japanese Patent Application Laid-Open No. 2000-214629 shows that a toner having roundness without corners on particles can be obtained.
No. 4,985,849, which has attracted attention as a toner capable of reproducing small dot images for digital images due to its fine line reproducibility and high resolution.

[0003] However, it is known that the dispersibility of the colorant added to the toner is inferior to the pulverized toner in the polymerized toner.
Polymerization is carried out after dispersing a pigment which is a colorant in the monomer.As the polymerization proceeds, the viscosity of the monomer droplets increases, causing aggregation of the colorant. The effect of the above causes the aggregation of the colorant to promote the aggregation of the colorant.

[0004] As described above, the polymerized toner has a problem that the dispersibility is deteriorated due to the aggregation of the colorant during the production process. On the other hand, the technique for improving the dispersion of the colorant is also actively studied. However, the technology has not yet achieved sufficient dispersibility of the colorant, and in particular, in a multicolor image forming method, a certain degree of transparency is required to form a color image by superimposing a plurality of color toners. This is a serious problem especially when an image is formed on an OHP film.

Further, in a polymerized toner, a surfactant and a dispersant used in the manufacturing process remain on the surface of toner particles as a final product, and these residues absorb moisture in the air. It causes the charge retention function of the toner to fluctuate and weakens the toner.In particular, in high-temperature and high-humidity environments, there is a problem of resolution reduction due to generation of fog, dust generation during development and transfer during toner destruction. ing.

Further, after the image forming apparatus has been shut down for a long period of time in a high-temperature and high-humidity environment, a state in which the toner having absorbed the water and the toner whose charge amount fluctuates and the new toner are mixed occurs, so that a halftone dot is formed. In a multi-color image formation, density unevenness is generated on a halftone image, and the effect of a colorant added to the toner of each color developer is also added. There is a problem that causes expansion.

[0007] To solve such a problem of the residue on the surface of the toner particles, as described in JP-A-57-150854, the washing of the generated toner is repeated to remove the impurities on the surface of the toner particles. Although a technique for suppressing the amount to a specific amount or less has been disclosed, a washing step using a large amount of water is not preferable because it complicates a toner manufacturing step and causes a new environmental problem.

In general, it is well known that the state in which a coloring agent is added to toner particles greatly affects toner performance such as resolution. For example, Japanese Patent Application Laid-Open No. 2000-81735 and Open 2000-284
No. 540 discloses that the ratio of the major axis to the minor axis of the colorant used in the pulverized toner and the number average diameter are specified to improve the dispersibility of the colorant in the toner, thereby improving the color reproducibility and the charge stability. Although it is disclosed that this is achieved, they specify the colorant before addition to the toner particles, and do not suggest the state of the colorant in the toner particles.

The colorant dispersion state in the toner particles is such that the transparency of the colorant is high if the colorant is uniformly dispersed in the toner particles without a phase separation structure such as a sea-island structure or a structure in which the colorant is aggregated. Although excellent, the charge retention function tends to decrease, and those having a phase separation structure or agglomeration have a good charge retention function but poor light transmission. JP-A-5-88409 and the like disclose a capsule toner in which a colorant is agglomerated in one particle and a resin is wrapped around the particle in a capsule shape. However, the expected transparency was not obtained because light scattering occurred at the interface between the colorant region and the resin. As described above, a polymerized toner having both a good charge holding function and transparency has not appeared yet.

[0010]

SUMMARY OF THE INVENTION The present invention has been made based on the above circumstances. That is, a first object of the present invention is to provide a toner for developing an electrostatic image which is not affected by the residue present on the surface of the toner particles and does not cause a change in the charge amount even under high temperature and high humidity. is there.

A second object of the present invention is to form a multicolor image having an appropriate dispersibility of a colorant in a toner particle, a high transparency, and a charge holding ability for obtaining a particularly beautiful OHP image. An object of the present invention is to provide a toner for developing an electrostatic image.

A third object of the present invention is to provide a toner for developing an electrostatic charge image which does not cause density unevenness of a halftone image even under a use condition in which the image forming apparatus is repeatedly stopped and used for a long period of time. It is.

A fourth object of the present invention is to provide a multi-color image forming apparatus which has been out of use for a long period of time under high temperature and high humidity conditions without being affected by the colorants contained in the respective color developers.
An object of the present invention is to provide a toner for developing an electrostatic image that can always obtain a multicolor image having a good color difference.

A fifth object of the present invention is to stably form a high-quality image excellent in developability and fine line reproducibility without causing character collapse regardless of the use environment and use conditions of the image forming apparatus. To provide a toner for developing an electrostatic image that can be used.

A sixth object of the present invention is to provide a digital multicolor image forming method using the toner for developing an electrostatic image.

[0016]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have studied the insomnia and non-stop, and according to the present invention, have achieved only the improvement of the dispersibility of the colorant in the toner particles. Instead, they found a technology that enabled them to achieve all of the above-mentioned issues. That is, in the present invention, focusing on the structure of the polymerized toner obtained by associating the resin particles and the color particles, the colorant forms islands in the toner particles, and the formed colorant islands form an optimal dispersion structure. Even if impurities such as a surfactant remain on the toner surface, the toner for developing an electrostatic charge image has a charge holding function without being affected by these and has excellent transparency.
A good image such as an HP image can be formed.

That is, in the present invention, when the colorant component forms islands in the binder resin, and the islands have an optimal dispersion structure in the particles, the islands can be used under a high temperature and high humidity use environment. Further, even under the condition in which the image forming apparatus is used for a long time after being stopped for a long period of time, the toner charge amount fluctuation such as the charge amount leakage does not occur. And a toner for developing an electrostatic image that forms a transparent OHP image with good transparency.

Further, the present invention has found that use of a water-wet colorant paste in the form of a colorant further improves transparency and color difference fluctuation. The present invention has been found to be achieved by adopting any one of the following constitutions.

[1] An electrostatic image developing toner having toner particles containing at least a resin and a colorant,
The toner particles have a sea-island structure, and the average value of the area of the Voronoi polygon formed by the perpendicular bisector between the centers of gravity of adjacent islands in the sea-island structure is 20,000.
A toner for developing an electrostatic charge image, which has a coefficient of variation of 0 to 120,000 nm ² and an area variation of the Voronoi polygon of 25% or less.

[2] In a toner for developing an electrostatic charge image having toner particles containing at least a resin and a colorant,
The toner particles have a sea-island structure, and the average value of the area of the Voronoi polygon formed by the perpendicular bisector between the centers of gravity of adjacent islands in the sea-island structure is 40,000.
A toner for developing an electrostatic charge image, wherein the toner has a coefficient of variation of up to 100,000 nm ² and a variation coefficient of the area of the Voronoi polygon of 20% or less.

[3] An electrostatic image developing toner having toner particles containing at least a resin and a colorant,
The toner particles have a sea-island structure, and the average value of the area of the Voronoi polygon formed by the perpendicular bisector between the centers of gravity of adjacent islands in the sea-island structure is 20,000.
0 to 120,000 nm ² and 160,000
An electrostatic image developing toner, wherein 3 to 20% by number of islands forming a Voronoi polygon having an area of at least nm ² are present.

[4] An electrostatic image developing toner having toner particles containing at least a resin and a colorant,
The toner particles have a sea-island structure, and the area of a Voronoi polygon formed by vertical bisectors between the centers of gravity of the islands located outside a circle having a radius of 1000 nm centered on the center of gravity in the cross section of the toner particles Is smaller than the average of the area of the Voronoi polygon formed by the perpendicular bisectors between the centers of gravity of the islands inside the circle.

[5] An electrostatic image developing toner having toner particles containing at least a resin and a colorant,
The toner particles have a sea-island structure, and are present in contact with the outer periphery of the toner among Voronoi polygons formed by vertical bisectors between the centers of gravity of adjacent islands in the sea-island structure; In addition, islands forming Voronoi polygons having an area of 160,000 nm ² or more are 3 to 20 of the entire islands.
A toner for developing an electrostatic charge image, characterized in that it is a number%.

[6] An electrostatic image developing toner having toner particles containing at least a resin and a colorant,
The toner particles have a sea-island structure, and have a length of 500 to 6000 nm along the outer periphery of the cross section of the toner particles.
A toner for developing an electrostatic image, comprising a region having a depth of 100 to 200 nm where no island portion exists.

[7] An electrostatic image developing toner having toner particles containing at least a resin and a colorant,
The toner particles according to any one of [1] to [6], wherein the toner particles have a sea-island structure, and the islands are formed of islands having different luminances. toner.

[8] An electrostatic image developing toner having toner particles containing at least a resin and a colorant,
The toner particles according to any one of the above items [1] to [7], wherein the toner particles have a sea-island structure, the resin forms a sea portion, and the colorant forms an island. An electrostatic image developing toner.

[0027]

[9] In a toner for developing an electrostatic charge image having toner particles containing at least a resin and a colorant,
The toner for developing an electrostatic image according to any one of [1] to [8], wherein the colorant is a water-wet colorant paste.

[10] The toner according to [1], wherein the toner has a number variation coefficient of 27% or less in a number particle size distribution and a shape coefficient variation coefficient of 16% or less.

The toner for developing an electrostatic image according to any one of [9].

[11] The toner according to [1] to [1], wherein the ratio of toner particles having no corners is 50% by number or more and the number variation coefficient in the number particle size distribution is 27% or less.

The toner for developing an electrostatic image according to any one of [9].

[12] The toner has a shape factor of 1.2 to 1.2.
The ratio of the toner particles in the range of 1.6 is 65% by number or more, the coefficient of variation of the shape coefficient is 16% or less, and the number variation coefficient in the number particle size distribution is 27% or less. The above [1]-

The toner for developing an electrostatic image according to any one of [9].

[13] The toner has a number average particle size of 3 to 3.
The toner for developing an electrostatic image according to any one of [1] to [12], which has a thickness of 9 μm.

[14] When the particle size of the toner particles is D (μm), the natural logarithm InD is plotted on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23. (M1) of the relative frequency (m1) of the toner particles included in the most frequent class and the relative frequency (m2) of the toner particles included in the class having the next highest frequency in the histogram indicating the particle size distribution of ) Is 70% or more, the toner for developing an electrostatic image according to any one of the above [1] to [13].

[15] The toner for developing an electrostatic image according to any one of [1] to [14], comprising at least a resin and a colorant, wherein at least the polymerizable monomer is an aqueous medium. A toner for developing an electrostatic image, which is obtained by polymerizing in a toner.

[16] The electrostatic image developing toner according to any one of [1] to [15], which contains at least a resin and a colorant, wherein at least the resin particles are aggregated in an aqueous medium. And a toner for developing an electrostatic image, which is obtained by fusing.

[17] The toner for developing an electrostatic image according to any one of the above [1] to [16], which contains at least a resin and a colorant, wherein the toner comprises at least a polymerizable monomer. A toner for developing an electrostatic image, wherein the toner is obtained by salting out / fusing resin particles and colorant particles formed through a process of polymerizing a body.

[18] The electrostatic image developing toner according to any one of [1] to [17], comprising at least a resin and a colorant, wherein the toner is obtained by a multi-stage polymerization method. The toner for developing an electrostatic image, which is obtained by salting out / fusing the obtained resin particles and colorant particles.

[19] The toner for developing an electrostatic image according to any one of [1] to [18], which contains at least a resin and a coloring agent, wherein the toner comprises resin particles and coloring particles. A toner for developing an electrostatic charge image, which is obtained by forming a resin layer formed by fusing resin particles on a surface of the resin by a salting-out / fusion method.

[20] A method for producing a toner for developing an electrostatic image containing at least a resin and a colorant, the method comprising producing the toner according to any one of [15] to [19]. A method for producing a toner for developing an electrostatic image.

[21] In an image forming method comprising the steps of converting an electrostatic latent image formed on a photoreceptor into a visible image, transferring the visible image onto a recording medium, and heat-fixing, the heat-fixing is performed in the form of an endless belt. An image forming method, wherein the image formation is performed by using a toner for developing an electrostatic image according to any one of the above [1] to [14].

[22] The image forming method according to [21], further comprising a step of converting the electrostatic latent image formed on the photoreceptor into a visible image, transferring the visible image onto a recording medium, and fixing by heating. And irradiating the photosensitive member with digital exposure.
Hereinafter, the present invention will be described in detail.

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION The toner particles of the present invention have a sea-island structure. The sea-island structure refers to a structure in which an isolated island-like phase exists in a continuous phase. That is, in the toner of the present invention, the respective components of the resin and the colorant constituting the toner particles do not mix with each other, and each independently forms a phase, so that the toner particles have a sea-island structure. . The present invention has a structure in which the island of the colorant exists in the continuous phase (sea) of the resin due to the nature of the toner.

The fact that the structure of the toner particles of the present invention has a sea-island structure means that a sea area and an island area are present in the toner particles by a cross-sectional photograph taken with a transmission electron microscope. Confirmed by being shown with a different area. That is, the transmission electron microscope confirms that the toner particles of the present invention have granular islands (colorant phase) having different luminances in the continuous phase (binder resin phase). Further, from the results of observation with an electron microscope, factors specifying the sea-island structure in the toner particles, such as the number of islands in one toner particle and the shape factor of the island, can be obtained as numerical values.

The luminance in a transmission electron microscope is caused by visualizing a difference in electron beam transmittance generated due to each element constituting the toner particles, that is, a binder resin and a colorant. Since the colorant has a lower electron beam transmittance than the binder resin, the colorant is photographed with low brightness.

In electron micrographs, low luminance is defined as 0 when a luminance signal of a pixel is divided into 256 gradations.
~ 99 gradations, medium brightness is 80 ~ 160
In the range of gradations and high luminance are those in the range of 127 to 255 gradations, but in the present invention, it is only necessary that the relative ones, that is, the components of the toner particles described above can be discriminated from each other by photograph, and not necessarily. It is not essential that the brightness of the colorant be within the low brightness range defined by the above range.

As described above, in the present invention, by identifying each component in the toner particles based on the luminance,
The sea is the sea, and the islands are the islands, which can be visually determined and identified by electron micrographs. Images in which the luminance information can be visually identified by an image analyzer installed in the electron microscope. It is converted into information.

FIGS. 1A and 1B are schematic diagrams each showing an example of the toner particles having the sea-island structure of the present invention. In the electron micrograph, the toner particles of the present invention are the schematic diagrams. As shown in Fig. 7, it is confirmed that the structure is composed of a continuous phase and an island portion. It is also confirmed that there is a region having an island with a length a and a depth b along the outer periphery of the toner particles.

Further, in FIG. 1, it was confirmed that, as islands in the toner particles, in addition to the islands of the colorant, the binder resin as a component of the toner particles also formed an island structure in the continuous phase. Is done.

The transmission electron microscope apparatus capable of observing the structure of the toner particles of the present invention is usually sufficiently observed with a model well known to those skilled in the art.
00 type (manufactured by Topcon Corporation) ”and the like. In the present invention, the values obtained from the results of transmission electron micrographs such as the number of islands in the toner particles, which are the features of the present invention, are obtained from the projected surface of 1,000 or more toner particles at a magnification of 10,000 times. It is calculated.

In the present invention, a photographing method using a transmission electron microscope is carried out by a generally known method for measuring toner particles. That is, as a specific method for measuring the tomographic plane of the toner, the toner is sufficiently dispersed in a room temperature curable epoxy resin, then embedded and cured, and dispersed in styrene fine powder having a particle size of about 100 nm. After post-press molding, the obtained block is dyed using ruthenium tetroxide or osmium tetroxide in combination, and a flaky sample is cut out using a microtome with diamond teeth, and the transmission electron Microscope (T
EM) was used to photograph the tomographic morphology of the toner. From the photograph, the shape of the colorant region in the toner particles is visually confirmed, and an image processing apparatus “Luzex F” (manufactured by Nireco Corporation) provided in the electron microscope apparatus is used.
Thus, the characteristics of the island portion in the toner particles can be obtained by arithmetic processing of the photographed image information.

According to the above method, the structure of the toner particles of the present invention is specified. Hereinafter, the factors for specifying the structure of the toner particles of the present invention will be described in detail.

The islands of the colorant component present in the toner particles of the present invention are indicated by islands B in the schematic diagram of FIG. As is apparent from this schematic diagram, in the toner particles having the sea-island structure of the present invention, in addition to the islands of the colorant component, islands of other elements constituting the toner particles may be present. Since the component islands and the other islands have different luminances, they can be easily identified in an electron micrograph. The island of the colorant component in the toner particles of the present invention is specified based on the Voronoi polygon area described below.

The numerical value specifying the island portion in the sea-island structure in the toner particles of the present invention is calculated by an image analyzer attached to the electron microscope device based on the image information observed by the electron microscope device.

The area of the Voronoi polygon used in the present invention indicates the occupancy of the islands in the toner particles. A Voronoi polygon or Voronoi polyhedron is
For example, as described in the Encyclopedia of Physical and Chemical Sciences of Iwanami, when a large number of points are dispersed in space or on a plane, by creating a perpendicular bisector and a perpendicular bisector of adjacent points The whole space is divided into polyhedra or the whole plane is divided into polygons.Polyhedrons formed in this way are called Voronoi polyhedra, polygons are called Voronoi polygons, and such division of space and plane is called Voronoi division . FIG. 2 shows an example of the toner particles of the present invention divided by a Voronoi polygon.

As described above, in the present invention, the occupation state of the toner particles in the sea-island structure is represented by the area of a Voronoi polygon obtained by Voronoi division as a scale representing the proportion of the islands in the toner particles. Things. That is, the present invention focuses on the centers of gravity of the islands present in the toner particles, forms polygons by vertical bisectors formed by connecting the centers of gravity of adjacent islands, and transmits the areas of these polygons through the transmission area. The calculation is performed by an image analyzer installed in the electron microscope apparatus based on the result of the photograph taken by the scanning electron microscope.

The Voronoi polygon having a large area is as follows.
This indicates that the distance between the centers of gravity of adjacent islands is distant, that is, the island is occupied sparsely in the particle. In addition, a Voronoi polygon having a small area indicates that the distance between the centers of gravity of adjacent islands is short and close, that is, the occupation state of islands in particles is dense. Things. In the present invention, the Voronoi polygon of the island portion in the toner particles is measured for 1000 toners, and the average value per toner particle is calculated.

The Voronoi polygon is mathematically generally defined by the following equation. <Area of Voronoi polygon> N independent points P (i) (1 ≦ i) in two-dimensional space R2 or three-dimensional space R3
≤N), the set of Voronoi polygons V (i) is: V (i) = ｛X || XP (i) | <| XP (j) |
(where X and P are position vectors and | | indicates a distance in Euclidean space.) V (i) thus defined is a Voronoi polygon with R2,
Assuming that R3 forms a Voronoi polyhedron, V (i)
And V (j) are adjacent, the boundary of the Voronoi polygon is
It is defined as a part of a perpendicular bisector of a line connecting the point P (i) and the point P (j). The Euclidean space is as defined and described in the Iwanami Dictionary of Physical and Chemical Sciences, the Dictionary of Mathematical Sciences, and the like.

Further, the center of gravity of the toner particles of the present invention and the center of gravity of each island in the toner particles are obtained by the moment of the image, and are automatically calculated by the image analyzer installed in the transmission electron microscope. You. Here, the barycentric coordinates of the toner particles are obtained by multiplying a luminance value of a small area at an arbitrary point of the toner particle by a coordinate value of the arbitrary point. Then, for all coordinates existing in the entire toner particle, the product of the luminance and the coordinate value is obtained, and the sum of the products is calculated as the luminance of the toner particle (the sum of the luminance values at each coordinate point obtained as described above). It is required by dividing. Similarly, the center of gravity of the island is calculated by calculating the luminance at an arbitrary coordinate point in the island. As described above, both the barycentric coordinates of the toner particles of the present invention and the barycentric coordinates of each island present in the toner particles are calculated based on the brightness at each arbitrary point, that is, from the brightness of the image.

In the present invention, the average value of the area of the Voronoi polygon formed by the perpendicular bisector between the centers of gravity of adjacent islands in the toner particles is 20,000 to 120,000 nm.
² , and the coefficient of variation of the average value of the area is 25% or less. In the present invention, the coefficient of variation of the area of the Voronoi polygon is calculated by the following equation.

Coefficient of variation of Voronoi polygon area = ｛S1
/ K1｝ × 100 (%) [where S1 represents the standard deviation of the area of the Voronoi polygon of the island portion present in the toner particles, and K1 represents the average value of the area of the Voronoi polygon. Further, the average value of the area of the Voronoi polygons of adjacent islands in the toner particles of the present invention is more preferably 4
It is from 000 to 100,000 nm ² and its coefficient of variation is 20% or less.

Further, in the toner particles of the present invention, the average value of the area of the Voronoi polygons of adjacent islands in the toner particles is 20,000 to 120,000 nm ² , and the area is 160,000 nm ² or more. The number of islands forming a Voronoi polygon having the following is 3 to 20% by number of the entire islands, and from the viewpoint of further uniforming the charge amount distribution, the area is preferably 50,000 nm ² or less. Is 30% by number or more, more preferably 60% by number or more of the entire islands present in one toner particle.

The average value of the area of the Voronoi polygon formed by the perpendicular bisector between the centers of gravity of adjacent islands in the toner particles of the present invention is in the range of 20,000 to 120,000 nm ^2. However, if it is out of this range, the occupation state of the island portion in the toner particles becomes unfavorable, for example, the colorant present as an island in the particle is not effectively added to the toner particle. It is difficult to find the effect of the present invention, which is not preferable.

The variation coefficient of the average value of the area of the Voronoi polygon formed by the adjacent islands in the toner particles of the present invention is the one that specifies the variation of the area of the Voronoi polygon.
That is, the variation of the occupation state of the island portion in the toner particles is specified, and the variation coefficient of the average value of the area of the Voronoi polygon may be in a range of 25% or less, and preferably 20% or less. When the coefficient of variation is 0%,
That is, the state in which the average value of the Voronoi polygon area does not vary, in other words, the state in which the occupation state of the islands in the toner particles does not vary at all, that is, the necessity of the same occupation state of the islands in all the toner particles is required. There is nothing at all.

In the present invention, if the variation coefficient of the average value of the area of the Voronoi polygons exceeds 25%, the variation between the areas of the obtained Voronoi polygons becomes too large. It is extremely difficult to find it, which is not preferable.

Further, in the present invention, 3-20% by number of islands having an area of 160,000 nm ² or more of Voronoi polygons are present in one toner particle. Means that the islands are moderately dispersed, and that the islands are appropriately spaced apart from each other in this way, the islands are not unevenly distributed in the toner particles, This means that the agent is effectively added to the toner particles.

Further, in the present invention, the area of the Voronoi polygon formed by islands existing within a specific range from the center of gravity of the toner particles is larger than the area of the Voronoi polygon formed by islands existing outside the range. It is characterized by being small. That is, in the present invention, the average value of the area of the Voronoi polygon formed by the islands existing outside the radius of 1000 nm from the center of gravity of the toner particles is 1
This is larger than the average value of the area of the Voronoi polygons formed by the islands within 000 nm, which means that in the toner particles, the dispersed state of the islands is sparse at a certain distance from the center of gravity of the toner particles. It means that it is. By satisfying this condition, in the toner of the present invention, the effect achieved by the present invention by appropriately dispersing the islands in the toner particles can be found.

Further, in the toner of the present invention, the toner particles have a sea-island structure, but have a region where no island exists in a region along the outer periphery of the toner particles. In the schematic diagrams of FIGS. 1A and 1B, a region indicated by a length a and a depth b along the outer periphery of the cross section of the toner particle is a region not including an island. That is, it has been confirmed that the toner of the present invention has a region which does not include an island at all along the outer periphery of the cross section of the toner particle.
0-200 nm, more preferably 120-180 n
m, the length is 500 to 6000 nm, more preferably 800 to 4000 nm.

In the toner of the present invention, as described above, the island is not present in the specific region along the outer periphery of the toner particles, so that the charge retention performance is enhanced and the occurrence of light scattering near the surface of the toner is prevented. It is presumed that it is. Further, it is presumed that the effect found in the present invention is promoted by optimally dispersing the colorant added to the toner particles in the particles. Those having no colorant-free region along the outer periphery of the toner particle cross section as in the present invention reduce the charge retention performance of the toner particles, and it is difficult to reproduce the effects found in the present invention. become.

The colorant (hereinafter, also referred to as colorant particles) used in the toner of the present invention is obtained by dispersing a fine particle having a weight average particle diameter of 30 to 500 nm into fine particles in a toner production process and dispersing the fine particles into toner particles. It is to be added. A specific description of a method for producing the colorant particles having the weight average particle size will be described later. In the present invention, it is effective to control the structure of the above-mentioned toner particles such as Voronoi polygons by using a colorant dispersed by a dispersing device as shown in FIG. In the present invention, when a water-wet colorant paste is used as a colorant, OHP
This is effective in improving the effects of the present invention, such as improving the transparency of the sheet. A specific description of the water-wet colorant paste will be described later.

The sea part of the toner particles having the sea-island structure of the present invention is made of resin.

In the toner particles having a sea-island structure of the present invention, islands of other toner components may be present in addition to islands of the colorant component. Examples of the island include an island of a crystalline substance. The crystalline substance is an organic compound having a melting point, and is preferably a hydrocarbon compound having an ester group in the compound structure. The melting point of the crystalline substance in the toner particles of the present invention is a temperature lower than the softening point of the toner, specifically 130.
It is below ° C. The organic compound preferably has an ester group in its structure, and includes a crystalline polyester compound.

As a method for confirming the melting point of the crystalline substance constituting the island portion, a method confirmed by DSC is used.
The fact that it has crystallinity is confirmed by means such as an X-ray diffractometer. Further, the crystalline substance contained in the toner of the present invention includes a substance exhibiting a function as a release agent during image formation.

The crystalline material has a melting point of 50 to 130 ° C.
And more preferably 60 to 120 ° C.
It is. In the case of a toner containing a crystalline substance having a melting point in the range of 50 to 130 ° C., the melt viscosity can be reduced, the adhesiveness to paper or the like can be improved, and the crystalline substance is not present. However, since the elastic modulus on the high temperature side is maintained in a preferable range, good offset resistance is exhibited.

When the melting point of the crystalline substance is less than 50 ° C., although the fixability itself is improved, the storage stability is reduced, and a problem is raised in practicality. On the other hand, when the melting point exceeds 130 ° C., the melting start temperature becomes high, so that the contribution to the improvement of the fixing property is low, and the effect of the improvement of the fixing property is less exhibited.

Here, the melting point of a crystalline substance refers to a value measured by a differential calorimeter (DSC).
The melting point is the temperature at which the maximum endothermic peak measured when the temperature is raised from 0 ° C. to 200 ° C. at a rate of 10 ° C./min (first temperature raising step) is measured. The melting point is determined by an endothermic peak (P
1) ".

As a specific measuring device for the melting point, DSC-7 manufactured by Perkin Elmer Co., Ltd. can be mentioned.
The specific method of measuring the melting point by a differential calorimeter (DSC) is as follows.
The temperature at which the maximum endothermic peak is measured at that time is defined as the endothermic peak P1 in the first heating process. Then 200 ° C
After leaving for 1 minute at a temperature of 10 ° C./min, the temperature at which the maximum exothermic peak is measured is defined as the exothermic peak P2 in the first cooling process.

The crystalline substance used in the toner of the present invention has an endothermic peak (P1) in the first temperature raising process by DSC.
Is present at 50 to 130 ° C, especially 60 to 120 ° C. Further, the exothermic peak (P2) in the first cooling step by DSC is 30 to 110 ° C, particularly 40 to 120 ° C.
Is preferably present. Here, the endothermic peak (P
1) and the heat generation peak (P2) satisfy the relationship of P1 ≧ P2. The temperature difference (P1−P2) is not particularly limited, but is preferably 50 ° C. or less.

By containing a crystalline substance having the above-mentioned thermal characteristics, an excellent offset prevention effect (wide fixing temperature range) and an excellent fixing property (high fixing rate) can be exhibited. In order to exhibit the effects of the present invention, it is preferable that the binder resin and the crystalline substance exist in a state where they are separated from each other.

That is, the crystalline substance dissolves sharply, and as a result, the melt viscosity of the whole toner can be reduced, and the fixing property can be improved. Also,
The presence of the phases separated from each other makes it possible to suppress a decrease in the elastic modulus on the high temperature side, so that the offset resistance is not impaired.

When the endothermic peak (P1) is below 50 ° C., the melting temperature is low, so that the fixing property is improved, but the storage stability is lowered. In addition, the endothermic peak (P
When 1) is in a range exceeding 130 ° C., the melting temperature is high, and as a result, it is impossible to improve the fixability and the offset resistance.

Exothermic peak (P2) indicating the state of recrystallization
If it is below 30 ° C., it cannot be recrystallized without cooling to a much lower temperature, and such a substance will be present in the toner with low crystallinity, and the Cannot contribute to the improvement of If the heat generation peak (P2) is in a range exceeding 110 ° C., the recrystallization temperature is too high, and the so-called melting temperature becomes high, and the low-temperature fixability is impaired.

Next, the shape of the toner of the present invention will be described in detail. The toner particles used in the present invention have a variation coefficient of shape factor of 16% or less, and a toner composed of toner particles having a number variation coefficient of 27% or less in a number particle size distribution. The presence state of the external additive becomes uniform, the charge amount distribution becomes sharp, and high fluidity is obtained. As a result, developability,
Excellent reproducibility of fine lines and stable cleaning properties can be formed over a long period of time.

Further, the inventors of the present invention have conducted a study focusing on the minute shape of each toner particle. As a result, the shape of the corner portion of the toner particle changes and becomes round inside the developing device, and the portion becomes round. It was found that the embedding of the external additive was promoted, and the change in the charge amount, the fluidity, and the cleaning property were reduced.

In addition, when electric charge is applied to toner particles by frictional charging, it is presumed that the external additive tends to be buried particularly in the corners, and the toner particles are likely to be non-uniformly charged. That is, the ratio of toner particles having no corners is 50% by number or more, and the number variation coefficient in the number particle size distribution is 27%.
%, Excellent toner developability and fine line reproducibility by using toner composed of toner particles controlled to less than
It has been found that high-quality images can be formed over a long period of time.

Further, it was found that even when the toner was made to have a specific shape and the shape was made uniform, no external additive was buried and the charge amount distribution became sharp. That is, the percentage of toner particles having a shape coefficient in the range of 1.2 to 1.6 is 65% by number or more, and the variation coefficient of the shape coefficient is 16%.
It has also been found that the use of the following toners makes it possible to form a high quality image over a long period of time with excellent developability and fine line reproducibility.

Here, the number particle size distribution and the number variation coefficient of the toner of the present invention will be described. The number particle size distribution and the number variation coefficient of the toner of the present invention are measured by a Coulter Counter TA-II or a Coulter Multisizer (manufactured by Coulter). In the present invention, a Coulter Multisizer was used and connected to an interface (manufactured by Nikkaki Co., Ltd.) for outputting a particle size distribution and a personal computer. The aperture used in the Coulter Multisizer is 100
The particle size distribution and the average particle size were calculated by measuring the volume diameter and the number diameter of 2 μm or more using a μm particle size. The number particle size distribution represents the relative frequency of the toner particles with respect to the particle size, and the number average particle size represents the cumulative 50% diameter in the number particle size distribution, that is, Dn50.

The number variation coefficient in the number particle size distribution of the toner is calculated from the following equation. Number variation coefficient = [S / Dn] × 100 (%) [where S represents a standard deviation in the number particle size distribution, and D
n indicates a number average particle size (μm). The number variation coefficient of the toner of the present invention is 27% or less, and preferably 25% or less. When the number variation coefficient is 27% or less, the gap of the transferred toner layer is reduced, the fixing property is improved, and the offset is less likely to occur. Further, the charge amount distribution is sharpened, the transfer efficiency is increased, and the image quality is improved.

The method of controlling the number variation coefficient of the present invention is not particularly limited. For example, a method of classifying toner particles by wind force can be used, but classification in a liquid is effective for further reducing the number variation coefficient. As a method of classifying in the liquid, there is a method in which a centrifugal separator is used to separate and collect toner particles according to a difference in sedimentation speed caused by a difference in toner particle diameter by controlling a rotation speed.

Next, the shape factor of the toner of the present invention will be described. The toner of the present invention has a shape factor of 1.2 to 1.
The ratio of the toner particles in the range of 6 is 65% by number or more, the variation coefficient of the shape coefficient is 16% or less, and the number variation coefficient in the number particle size distribution is 27% or less. Here, the shape factor of the toner of the present invention is represented by the following equation, and indicates the degree of roundness of the toner particles.

Shape factor = ((maximum diameter / 2) ² × π) / projected area Here, the maximum diameter is defined as a parallel image obtained by sandwiching a projected image of a toner particle on a plane between two parallel lines. Means the width of the particle at which the distance between the particles becomes maximum. The projection area refers to the area of the projected image of the toner particles on the plane. In the present invention, the shape factor can be determined by taking a photograph in which the toner particles are magnified 2,000 times with a scanning electron microscope, and then referring to the “SCCANNING IMAGE ANALYZE” based on the photograph.
R "(manufactured by JEOL Ltd.) was used to analyze photographic images. At this time, the shape factor of the toner of the present invention was measured by using the above-mentioned calculation formula using 100 toner particles.

Next, the toner of the present invention having no corners will be described. Here, the toner particles having no corners refer to toner particles having substantially no protrusions on which electric charges are concentrated or which are easily worn by stress, that is, as shown in FIG. 8A. When the major axis of the toner particle T is L, a circle C having a radius (L / 10) is rolled inward while being in contact with the peripheral line of the toner particle T at one point. The case where the toner does not substantially protrude outside the toner T is referred to as “toner particles having no corners”.
“Cases that do not substantially protrude” refer to cases where there are no more than one protrusion having a protruding circle.

[0091] The "major axis of the toner particle" means the width of the particle at which the distance between the parallel lines becomes maximum when the projected image of the toner particle on the plane is sandwiched between two parallel lines. FIGS. 8B and 8C are schematic diagrams showing projected images of toner particles having corners, respectively.

The measurement of the toner having no corners was performed as follows. First, a photograph in which the toner particles are enlarged by a scanning electron microscope is taken, and further enlarged to obtain a 15,000-fold photographic image. Next, the presence or absence of the corners is measured for this photographic image. This measurement was performed for 1000 toner particles.

In the toner of the present invention, the proportion of toner particles having no corners is at least 50% by number, preferably at least 70% by number. When the ratio of the toner particles having no corners is 50% by number or more, generation of fine particles and the like due to stress with the developer conveying member and the like are less likely to occur,
So-called contamination on the surface of the developer conveying member can be suppressed, the charge amount distribution becomes sharp, the chargeability is stabilized, and good image quality can be formed for a long period of time.

The method for obtaining a toner having no corners is not particularly limited. For example, as described above, as a method of controlling the shape coefficient, a method of spraying toner particles into a hot air flow, a method of repeatedly applying mechanical energy by an impact force in a gas phase, or a method of dissolving a toner It can be obtained by adding to a solvent that does not contain and giving a swirling flow.

In the toner of the present invention, when the particle size of the toner particles is D (μm), the natural logarithm InD is plotted on the horizontal axis, and the horizontal axis is divided into a plurality of classes at intervals of 0.23. In the histogram showing the standard particle size distribution, the sum of the relative frequency (m1) of the toner particles included in the most frequent class and the relative frequency (m2) of the toner particles included in the next most frequent class after the most frequent class. It is preferable that the toner has (M) of 70% or more.

When the sum (M) of the relative frequency (m1) and the relative frequency (m2) is 70% or more, the dispersion of the particle size distribution of the toner particles becomes narrower. Thus, the occurrence of selective development can be reliably suppressed.

In the present invention, the histogram showing the number-based particle size distribution is obtained by plotting a natural logarithm lnD (D: particle size of individual toner particles) in a plurality of classes (0 to 0) at intervals of 0.23.
0.23: 0.23 to 0.46: 0.46 to 0.69:
0.69 to 0.92: 0.92 to 1.15: 1.15
1.38: 1.38 to 1.61: 1.61 to 1.84:
1.84 to 2.07: 2.07 to 2.30: 2.30 to
2.53: a histogram showing the number-based particle size distribution divided into 2.53 to 2.76..., Which is a particle size data of a sample measured by a Coulter Multisizer according to the following conditions. Is transferred to a computer via an I / O unit, and the computer creates the program using a particle size distribution analysis program.

[Measurement conditions] 1: Aperture: 100 μm 2: Sample preparation method: Electrolyte [ISOTON II (manufactured by Coulter Scientific Japan)] 50-1
An appropriate amount of a surfactant (neutral detergent) is added to 00 ml and stirred, and 10 to 20 mg of a measurement sample is added thereto. This system is prepared by subjecting it to a dispersion treatment with an ultrasonic disperser for 1 minute.

Next, the particle size of the toner of the present invention will be described. The toner used in the present invention has a number average particle diameter of 3 to 9 μm, preferably 4.5 to 8.5 μm, and more preferably 5 to 8 μm. This particle size is
In the method for producing toner particles, the concentration can be controlled by the concentration of the coagulant (salting agent), the amount of the organic solvent added, the fusing time, and the composition of the polymer.

When the number average particle diameter is 3 to 9 μm, the transfer efficiency is increased, the image quality of halftone is improved, and the image quality of fine lines and dots is improved. The calculation of the particle size distribution of the toner and the measurement of the number average particle size are performed using a Coulter Counter TA.
-II, Coulter Multisizer (both from Coulter), SLAD1100 (Shimadzu Corporation laser diffraction particle size analyzer) and the like. In the present invention, measurement and calculation are performed using a Coulter Multisizer, an interface for outputting a particle size distribution (manufactured by Nikkaki Co., Ltd.), and a personal computer connected.

Next, a method for producing the toner of the present invention will be described. The toner of the present invention is obtained by polymerizing at least a polymerizable monomer in an aqueous medium, and this manufacturing method prepares resin particles by polymerizing the polymerizable monomer by a suspension polymerization method. Alternatively, emulsion polymerization or mini-emulsion polymerization of the monomer is performed in a liquid (in an aqueous medium) to which an emulsion of the necessary additives is added to prepare fine resin particles, and if necessary, charged. After adding controllable resin particles,
It is manufactured by a method of adding an organic solvent, a coagulant such as salts and the like, and coagulating and fusing the resin particles. <Suspension polymerization method> As an example of a method for producing the toner of the present invention, a charge control resin is dissolved in a polymerizable monomer,
Add various constituent materials such as colorant and release agent as needed, further polymerization initiator, etc., dissolve or disperse various constituent materials in polymerizable monomer with homogenizer, sand mill, sand grinder, ultrasonic disperser etc. Let it. The polymerizable monomer in which these various constituent materials are dissolved or dispersed is dispersed in an aqueous medium containing a dispersion stabilizer into oil droplets of a desired size as a toner using a homomixer, a homogenizer, or the like. Thereafter, the stirring mechanism is moved to a reaction device (stirring device), which is a stirring blade described later, and the polymerization reaction is advanced by heating. After completion of the reaction, the toner of the present invention is prepared by removing the dispersion stabilizer, filtering, washing and drying. The “aqueous medium” in the present invention means a medium containing at least 50% by mass of water. <Emulsion polymerization method> Further, as a method for producing the toner of the present invention, a method in which resin particles are prepared by salting out / fusion in an aqueous medium can also be mentioned. Although this method is not particularly limited, for example, Japanese Patent Application Laid-Open No. 5-2652
52, JP-A-6-329947 and JP-A-9
-15904 can be mentioned.
That is, a method of salting out, aggregating, and fusing a plurality of fine particles composed of a resin and a colorant, or a dispersion particle of a constituent material such as a resin particle and a colorant, particularly dispersing these in water using an emulsifier After that, a coagulant having a critical coagulation concentration or more is added and salted out, and at the same time, the formed polymer itself is heated and fused at a temperature of the glass transition temperature or more to gradually grow the particle size while forming fused particles. When the target particle size is reached, add a large amount of water to stop the particle size growth, further heat and stir to smooth the particle surface to control the shape, and heat the particles in a fluid state while keeping the particles wet. By drying, the toner of the present invention can be formed.
Here, a solvent such as alcohol which is infinitely soluble in water may be added together with the coagulant.

In the method for producing a toner according to the present invention, the composite resin fine particles and the colorant particles formed through a step of dissolving a crystalline substance in at least the polymerizable monomer and polymerizing the polymerizable monomer are used. It is obtained by salting out / fusing. The toner of the present invention dissolves a crystalline substance in a polymerizable monomer. The crystalline substance may be dissolved or dissolved, or may be dissolved and dissolved.

In the method for producing a toner of the present invention, the composite resin fine particles obtained by the multi-stage polymerization method and the colorant particles are salted out / fused. The multi-stage polymerization method will be described below. <Method for producing composite resin particles obtained by multi-stage polymerization method>
The method for producing a toner of the present invention comprises the following steps.

1: Multi-stage polymerization step 2: Salting-out / fusion step of salting-out / fusing the composite resin particles and colorant particles to obtain toner particles 3: Filtering out the toner particles from the dispersion system of the toner particles And
A filtration / washing step of removing a surfactant or the like from the toner particles; a drying step of drying the washed toner particles; and a step of adding an external additive to the dried toner particles.

Hereinafter, each step will be described in detail. [Multi-stage polymerization step] The multi-stage polymerization step is a polymerization method carried out to expand the molecular weight distribution of the resin particles in order to obtain a toner in which offset has been prevented. That is, in order to form phases having different molecular weight distributions in one resin particle, the polymerization reaction is performed in multiple stages, and the obtained resin particles have a molecular weight gradient from the center of the particle toward the surface layer. It is intended to be formed. For example, a method in which a high molecular weight resin particle dispersion is obtained first, and then a low molecular weight surface layer is formed by newly adding a polymerizable monomer and a chain transfer agent.

In the present invention, it is preferable to employ a multi-stage polymerization method of three-stage polymerization or more from the viewpoint of production stability and crushing strength of the obtained toner. Hereinafter, two-stage polymerization and three-stage polymerization, which are typical examples of the multi-stage polymerization, will be described. In the toner obtained by such a multi-stage polymerization reaction, those having a molecular weight as low as the surface layer are preferable from the viewpoint of crushing strength.

<Two-Step Polymerization Method> In the two-step polymerization method, a central part (nucleus) formed from a high molecular weight resin containing a crystalline substance is used.
And a method of producing composite resin particles comprising an outer layer (shell) formed of a low molecular weight resin.

More specifically, this method will be described. First, a crystalline substance is dissolved in a monomer to prepare a monomer solution, and this monomer solution is added to an aqueous medium (for example, a surfactant aqueous solution).
After the oil droplets are dispersed therein, this system is subjected to a polymerization treatment (first stage polymerization) to prepare a dispersion of high molecular weight resin particles containing a crystalline substance.

Next, a polymerization initiator and a monomer for obtaining a low-molecular-weight resin are added to the dispersion of the resin particles, and the monomer is subjected to a polymerization treatment (second-stage polymerization) in the presence of the resin particles. Is performed to form a coating layer made of a low molecular weight resin (monomer polymer) on the surface of the resin particles.

<Three-stage polymerization method> The three-stage polymerization method comprises a central part (nucleus) formed from a high molecular weight resin, an intermediate layer containing a crystalline substance, and an outer layer (shell) formed from a low molecular weight resin. This is a method for producing composite resin particles. The toner of the present invention exists as the composite resin particles as described above.

The method will be specifically described. First, a dispersion of resin particles obtained by a polymerization treatment (first-stage polymerization) according to a conventional method is added to an aqueous medium (for example, an aqueous solution of a surfactant). Along with the addition, a monomer solution obtained by dissolving a crystalline substance in a monomer is dispersed in the aqueous medium in oil droplets, and then the system is subjected to a polymerization treatment (second-stage polymerization). A coating layer (intermediate layer) made of a resin (monomer polymer) containing a crystalline substance is formed on the surface of the particles (core particles) to form a composite resin particle (high molecular weight resin-intermediate molecular weight resin). Prepare a dispersion.

Next, a polymerization initiator and a monomer for obtaining a low-molecular-weight resin are added to the obtained dispersion of the composite resin particles, and the monomer is subjected to a polymerization treatment (first step) in the presence of the composite resin particles. By performing the three-stage polymerization, a coating layer made of a low-molecular-weight resin (monomer polymer) is formed on the surfaces of the composite resin particles. In the above method, the incorporation of an intermediate layer is preferable because the crystalline substance can be finely and uniformly dispersed.

One feature of the toner production method according to the present invention is that a polymerizable monomer is polymerized in an aqueous medium. That is, when forming resin particles (core particles) or a coating layer (intermediate layer) containing a crystalline substance, the crystalline substance is dissolved in a monomer, and the resulting monomer solution is oiled in an aqueous medium. In this method, latex particles are obtained by dispersing droplets, adding a polymerization initiator to the system, and performing a polymerization treatment.

The aqueous medium referred to in the present invention is water 50 to 10
A medium comprising 0% by mass and 0 to 50% by mass of a water-soluble organic solvent. Examples of the water-soluble organic solvent include, for example, methanol, ethanol, isopropanol, butanol,
Acetone, methyl ethyl ketone, tetrahydrofuran and the like can be exemplified, and an alcohol-based organic solvent which does not dissolve the obtained resin is preferable.

As a polymerization method suitable for forming a resin particle or a coating layer containing a crystalline substance, a crystalline substance is dissolved in an aqueous medium in which a surfactant having a concentration equal to or lower than the critical micelle concentration is dissolved. The monomer solution dissolved in the monomer is dispersed in oil droplets using mechanical energy to prepare a dispersion, and a water-soluble polymerization initiator is added to the obtained dispersion, and the oil is dispersed in the oil droplets. A method of radical polymerization (hereinafter, referred to as a “mini-emulsion method” in the present invention) can be mentioned, and the effect of the present invention can be more exerted, which is preferable. In addition,
In the above method, an oil-soluble polymerization initiator may be used instead of or together with the water-soluble polymerization initiator.

According to the miniemulsion method in which oil droplets are formed mechanically, unlike a normal emulsion polymerization method, the crystalline substance dissolved in the oil phase is less detached, and the resin particles or the coating layer to be formed are formed. A sufficient amount of crystalline material can be introduced into the inside.

Here, the disperser for dispersing oil droplets by mechanical energy is not particularly limited. For example, a stirrer “CLEARMIX” equipped with a high-speed rotating rotor (M -Technic Co., Ltd.), an ultrasonic disperser, a mechanical homogenizer, a Menton-Gaulin and a pressure homogenizer. Further, the dispersion particle diameter is 1
0 to 1000 nm, preferably 50 to 1000 n
m, more preferably 30 to 300 nm. Here, by giving a distribution to the dispersed particle diameter, the phase separation structure of the crystalline substance in the toner particles, that is, the Feret diameter, the shape coefficient, and the variation coefficient thereof may be controlled.

As other polymerization methods for forming the resin particles containing the crystalline substance or the coating layer, known methods such as an emulsion polymerization method, a suspension polymerization method, and a seed polymerization method may be employed. . In addition, these polymerization methods can also be employed to obtain resin particles (core particles) or coating layers constituting the composite resin particles, which do not contain a crystalline substance.

The particle diameter of the composite resin particles obtained in this polymerization step is 10 to 10 as a mass average particle diameter measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.).
It is preferably in the range of 1000 nm.

Further, the glass transition temperature (T
g) is preferably in the range of 48 to 74 ° C, more preferably 52 to 64 ° C.

The softening point of the composite resin particles is 95-14.
It is preferably in the range of 0 ° C. The toner of the present invention
It is obtained by forming a resin layer formed by fusing the resin particles on the surfaces of the resin and the colored particles by a salting-out / fusion method. This will be described below. [Salt-out / fusion step] In the salt-out / fusion step, the composite resin particles and the colorant particles obtained by the multi-stage polymerization step are subjected to salt-out / fusion (the salt-out and fusion occur simultaneously). Make
This is a step of obtaining irregular (non-spherical) toner particles.

The salting out / fusion in the present invention means that salting out (aggregation of particles) and fusion (disappearance of interface between particles) occur simultaneously, or salting out and fusion occur simultaneously. Act. In order to simultaneously carry out the salting-out and the fusion, the particles (composite resin particles, colorant particles) under a temperature condition not lower than the glass transition temperature (Tg) of the resin constituting the composite resin particles.
Need to be aggregated.

In this salting out / fusion step, together with the composite resin particles and the colorant particles, internal additive particles (fine particles having a number average primary particle diameter of about 10 to 1000 nm) such as a charge controlling agent are salted out / fused. May be. [Aging step] The aging step is a step subsequent to the salting-out / fusion step, and after the fusion of the resin particles, the temperature is kept near the melting point of the crystalline substance, preferably at the melting point ± 20 ° C. In this step, the crystalline substance is phase-separated by continuing the stirring. In this step, it is possible to control the Feret diameter and the shape coefficient of the crystalline substance and the coefficient of variation thereof. [Colorant Fine Particles] The colorant fine particles used to obtain the toner of the present invention are formed by using a dispersing apparatus for uniformly finely dispersing the colorant fine particles in an aqueous medium containing a surfactant. It is. That is, the dispersing device shown in FIG. 3 is an example of a dispersing device that finely disperses the colorant fine particles preferably used in the toner of the present invention, and includes a screen that defines a stirring chamber and a rotor that rotates at high speed in the stirring chamber. A method in which a shear force is generated, and the colorant is finely dispersed in an aqueous medium containing a surfactant to obtain fine particles by the action of the shear force (further, the action of collision force, pressure fluctuation, cavitation, and potential core). It is.

In the present invention, finely dispersing the colorant using the dispersing device shown in FIG. 3 is effective in controlling the toner structure such as the Voronoi polygon.

It is effective to use the colorant used in the present invention in the form of a water-wet colorant paste in order to further improve the effects of the present invention in addition to controlling the toner structure. Hereinafter, the water-wet colorant paste will be described.

In the present invention, the use of a water-wet colorant paste as a colorant is effective in improving the transparency of OHP images and stabilizing color difference fluctuation.

That is, the effects of the present invention are further promoted by using toner particles having a specific particle shape and distribution described later and a colorant of a water-wet colorant paste. A water-wet colorant paste having a colorant content of 15 to 75% by mass is preferably used.

In the method for producing the water-wet colorant paste, after the synthesis of the colorant, after a purification step such as recrystallization, filtration and dehydration are performed to obtain a water-wet colorant paste adjusted to a desired colorant content. . Alternatively, water may be added to the dried colorant powder, and wet pulverization may be performed as needed, followed by filtration and dehydration to obtain a water-wet colorant paste adjusted to a desired colorant content. That is, the water-wet colorant paste preferably used in the present invention is a form that does not dry in the steps after the wet pulverization or the purification step in the manufacturing process and contains water to such an extent that the colorant particles do not aggregate. This is also called wet cake. The colorant used in the present invention may be a dye or an inorganic pigment in addition to the organic pigment, and those having the form of a water-wet colorant paste are preferably used.

More specifically, after the completion of the synthesis reaction, the colorant is usually washed and purified using water, filtered, dried, wetted with water, and dried. It becomes a powder colorant by pulverization. However, by performing drying after filtration, strong agglomeration occurs, and it is not possible to easily downsize to primary particles by physical pulverization. Therefore, in the present invention, it is possible to obtain a finely dispersed state by hardly aggregating the colorant particles by dispersing in a surfactant aqueous solution at the stage of the water-wet colorant paste before drying. I found it.

Further, as a water-wet colorant paste,
A water-wet colorant paste after milling treatment such as salt milling or solvent milling may also be used.Especially for applications requiring fine colorant particles, surface treatment with a water-wet paste without drying after salt milling is performed. By doing so, the modifying effect can be enhanced. Here, the salt milling is a process of making the coloring agent fine by milling the ground sodium chloride and the coloring agent in diethylene glycol. In addition, solvent milling is used as a process for controlling the crystal growth of the colorant particles to make the particle size uniform by milling in a specific solvent with a colorant, or utilizing the crystal transition by the solvent, This is a processing method for controlling the crystallinity to a desired value.

The organic pigments among the coloring agents used in the toner of the present invention are not particularly limited. Examples thereof include dye lakes, azos, benzimidazolones, phthalocyanines, quinacridones, anthraquinones, and dioxazines. System, indigo system, thioindigo system, perylene system, perinone system, diketopyrrolopyrrole system, anthranthrone system, isoindolinone system, nitro system, nitroso system, anthraquinone system, flavanthrone system, quinophthalone system, pyranthrone system, in Dunlon type and the like. The particle size of the pigment particles used is preferably 30 to 10
000 nm, preferably 30 to 500 nm, more preferably 50 to 300 nm.

As the colorant used in the toner of the present invention, a colorant that has been surface-treated with a sulfonating agent in order to enhance dispersibility may be preferably used. As a method, if a solvent that is insoluble or hardly soluble in a colorant is selected without causing the dispersing solvent of the reaction system to react with the sulfonating agent, a sulfonation reaction that can be performed by a normal organic reaction can be used. As the sulfonating agent, sulfuric acid, fuming sulfuric acid, sulfur trioxide, chlorosulfuric acid, fluorosulfuric acid, amidosulfuric acid and the like are used. In addition, when sulfur trioxide itself is too reactive to decompose or alter the pigment itself, or when it is difficult to control the reaction with a strong acid, sulfonation using a complex of sulfur trioxide and a tertiary amine is used. It is also possible to carry out (for example, see Shin-Jikken Kagaku Koza Vol. 14, No. 1, 1773, Maruzen). Also,
Pigment easily dissolves when used alone as sulfuric acid, fuming sulfuric acid, chlorosulfuric acid, fluorosulfuric acid, etc.For strong acids that react with each molecule, pay attention to the type of solvent and amount used to suppress the reaction There is a need to. The type of solvent in the reaction, the reaction temperature, the reaction time, the type of the sulfonating agent and the like cannot be specified because it differs for each type of colorant and each reaction system, but examples of the solvent that can be used include sulfolane, N-methyl-2-pyrrolidone,
Examples include dimethylacetamide, quinoline, hexamethylphosphoric triamide, chloroform, dichloroethane, tetrachloroethane, tetrachloroethylene, dichloromethane, nitromethane, nitrobenzene, liquid sulfur dioxide, carbon disulfide, and trichlorofluoromethane.

Further, a sulfonating agent is used as a sulfur trioxide complex, and the reaction solvent forms a complex with sulfur trioxide, a basic solvent such as N, N-dimethylformamide, dioxane, pyridine, triethylamine, trimethylamine, or nitromethane. Acetonitrile can be used alone or in combination with one or more other solvents described above, as long as it is reactive to form a complex with a sulfonating agent. Specific reaction examples will be described with reference to Examples.

The surface-treated colorant obtained by subjecting the colorant used in the toner of the present invention to a surface treatment reacts with a reactive functional group or an aromatic ring on the surface of the colorant to form a sulfonic acid group or the like on the surface of the pigment particles. It is considered that the binding of the colorant improves the affinity of the colorant with the resin particles and the polymerizable monomer as the binder resin, and exhibits excellent dispersion stability. Further, by binding the sulfonic acid group to the surface of the colorant particles, the treated colorant can be uniformly acidified, so that the toner is excellent in charge start-up and an image with higher resolution can be obtained. It is considered to be.

That is, the use of the water-wet colorant paste pigment of a specific shape and a specific colorant improves the dispersion of the colorant, and enhances the transparency of the image and the transparency of the OHP sheet. Become.

The colorant component in the colorant used in the toner of the present invention indicates the mass% of the colorant in the water-wet colorant paste. It is difficult to apply a shearing force, it is difficult to disintegrate the aggregates of the colorant, and a free pigment may be generated, which is not preferable for reproduction of the secondary color and OHP sheet permeability. Conversely, if it exceeds 75% by mass, the colorant particles tend to agglomerate due to concentration and dispersibility in the toner tends to be difficult, which is not preferable for OHP sheet permeability.

The above characteristics of the colorant can be controlled by the filtration conditions during the production of the colorant or during the purification.

Here, the surfactant contained in the aqueous medium in which the colorant fine particles are dispersed is a critical micelle concentration (CMC).
The surfactant is dissolved in the above concentration, and the same surfactant used in the polymerization step can be used.

The weight average particle size (dispersion particle size) of the colorant fine particles is from 30 to 500 nm, preferably from 50 to 30 nm.
0 nm. The weight average particle size of the colorant fine particles is 30.
When the average particle diameter is less than 500 nm, the coloring agent in the aqueous medium becomes intensely suspended, and when the weight average particle diameter exceeds 500 nm, the colorant particles are not easily dispersed in the aqueous medium and are likely to settle. Therefore, it becomes difficult to introduce the colorant into the toner particles. Under such conditions, the colorant particles are not taken in the toner particles and remain free in the aqueous medium, which is not preferable. The weight average particle size of the colorant fine particles was measured using an electrophoretic light scattering photometer “ELS-8”.
00 "(manufactured by Otsuka Electronics Co., Ltd.).

The fine particles of the colorant used in the toner of the present invention are prepared by adding a colorant to an aqueous medium containing a surfactant and then performing preliminary dispersion (coarse dispersion) with a propeller stirrer or the like. A preliminary dispersion of the aggregated particles is formed. The predispersion liquid is supplied to a stirrer provided with a screen for forming a partition in the stirring chamber and a rotor rotating at a high speed in the stirring chamber, and is subjected to a dispersion treatment (fine dispersion treatment) by the stirring device. Is prepared.

Among the colorant fine particles used in the toner of the present invention, as a stirring device for dispersion treatment to obtain colorant fine particles having a preferable dispersion state, "CLEARMIX" (M Technic Co., Ltd.) )
Manufactured). This "Clear Mix"
Has a rotor (stirring blade) that rotates at a high speed and a fixed screen (fixed ring) surrounding the rotor, and applies shear force, collision force, pressure fluctuation, cavitation, and the action of potential core to the liquid to be treated. It has a structure to be imparted, and effectively acts to emulsify / disperse the liquid to be treated by synergistically functioning these functions.

That is, this “Clear Mix” is originally used for the formation of an emulsion (dispersion of liquid fine particles), but the present inventors use it as an apparatus for dispersing colorant fine particles in an aqueous medium. By doing so, it has been found that a dispersion of colorant fine particles having a preferable average particle size and a sharp particle size distribution is obtained.

FIG. 3A is a schematic view showing a rotor rotating at high speed and a fixed screen surrounding the rotor. In FIG. 3A, reference numeral 101 denotes a screen, and M denotes an agitation defined by the screen 101. A rotor 102 rotates at a high speed in the stirring chamber M.

The rotor 102 is a stirring blade that rotates at a high speed, and its rotation speed is usually 4,500 to 22,000 rpm.
And preferably from 10,000 to 21,500 rpm. The peripheral speed of the tip of the rotor 2 is usually 10 to 40 m / s.
ec, preferably 15 to 30 m / sec.

The screen 101 arranged so as to surround the rotor 102 has a fixed ring composed of a number of slits (not shown). Slit width is 0.5-5mm
And preferably 0.8 to 2 mm. The number of slits is 10 to 50, preferably 15 to 30.
The gap (clearance) between the rotor 102 and the screen 101 is usually 0.1 to 1.5 mm, preferably 0.2 to 1.5 mm.
１．０1.0 mm.

The average particle size and particle size distribution of the colorant fine particles are adjusted by controlling the number of revolutions of the rotor 102 and the like, and can also be adjusted by selecting the shapes of the screen 101 and the rotor 102. Specifically, the screen (S1.0-24, S
1.5-24, S1.5-18, S2.0-18, S
3.0-9) and the rotors (R1 to R4) provide a preferable dispersion state, but may be a self-made one to obtain a more preferable dispersion state.

FIG. 3B is a schematic diagram showing a continuous processing apparatus (CLEARMIX) equipped with a rotor and a screen. The pre-dispersed dispersion liquid (pre-dispersion liquid) is supplied to the stirring chamber between the screen 101 and the rotor from the pre-dispersion liquid inlet 104 shown in FIG. The screen 101 and the rotor are
3, a temperature sensor 106, a cooling jacket 107, and a cooling coil 108 are arranged. The agglomerated particles of the colorant in the pre-dispersion are pulverized (finely dispersed) by applying a shearing force generated by the high-speed rotating rotor and the screen 1.

That is, the colorant aggregated particles in the preliminary dispersion liquid supplied to the band-shaped stirring chamber provided between the screen 101 and the rotor are subjected to a shearing force (mechanical force) generated by the high-speed rotation of the screen 101 and the rotor. Energy), and is disintegrated (finely dispersed) by the action of collision force, pressure fluctuation, cavitation, and a potentiometer in addition to the shearing force to form colorant fine particles. The dispersion of the colorant fine particles is ejected from the slit of the screen 101 into the pressurized vacuum attachment 103 to obtain a dispersion of the colorant fine particles having a preferable average particle diameter and a sharp particle diameter distribution. The dispersion containing the colorant fine particles is sent from the dispersion outlet 5 to the next step.

In the agitator, the aggregated colorant particles are disintegrated into fine colorant particles (dispersed particles) having a preferable average particle diameter and a sharp particle diameter distribution by the action of the rotor and the screen. , Due to a plurality of actions described below. (1) Near the surface of the high-speed rotating rotor (stirring blade)
Due to the large velocity gradient, a high shear rate region is formed near the surface, and the colorant aggregated particles are broken by the shear force generated in this region. (2) A vacuum portion (cavitation) is generated behind the rotor (stirring blade) when the rotation speed is high, and bubbles generated by the rotation are eliminated at a stage where the flow rate of the dispersion liquid is reduced. As a result, an impact pressure is generated, and the aggregated particles of the colorant are broken by the impact pressure. (3) The rotor (stirring blade) imparts pressure energy to the pre-dispersion liquid by high-speed rotation. When the pressure energy is rapidly released, the kinetic energy of the pre-dispersion liquid increases, and the pre-dispersion liquid flowing by the rotor is screened. The pressure energy is varied when repeatedly passing between an open portion (slit portion) and a closed portion (non-slit portion), thereby generating a pressure wave to break up the aggregated particles of the colorant. (4) When the pre-dispersion liquid having a large kinetic energy collides with a screen or other wall, the agglomerated particles of the colorant that have been subjected to the collision force are crushed into colorant fine particles having a sharp particle size distribution. (5) When the dispersion having the velocity energy passes through the slit portion of the screen, it becomes a jet (jet stream). The surrounding fluid is sucked at a high speed in the potential core (velocity region not affected by the viscous flow) in the jet. Agglomerated particles of the colorant that have received this energy are crushed into colorant fine particles having a sharp particle size distribution.

The dispersion time for obtaining the colorant fine particle dispersion is not particularly limited, but is 5 to 80 minutes.
Preferably, it is 7 to 65 minutes. When circulating, the number of passes is preferably 5 or more, and more preferably 5 to 20. If the dispersion time is too long, the dispersion becomes excessive and the amount of the fine particles increases, which is not preferable.

In order to obtain the colorant fine particles preferably used in the toner of the present invention, a dispersion container equipped with a stirring device having a screen and a rotor is used. Alternatively, a batch-type dispersion treatment may be performed in which a colorant (aqueous medium containing a colorant) is ejected from a stirring chamber of the stirring device.

FIG. 3C is a schematic view showing a dispersion container provided with such a stirring device (Clear Mix).
Distributed processing is performed by such an apparatus. FIG. 3 (c)
, 111 is a dispersion container, 112 is a stirrer, 11
Reference numeral 3 denotes a stirring shaft for driving the stirring device 112. The stirring device 112 has the same configuration (screen and rotor) as that shown in FIG.

Pre-dispersion (dispersion of agglomerated particles of colorant)
The strong shear force generated between the rotor and the screen, which enters the stirring chamber from the top of the stirring device 112 and rotates at high speed,
Stirred by impact force and turbulence, weight average particle size is 3
Colorant fine particles having a size of 0 to 300 nm are formed, and are ejected from the slits of the screen into the dispersion container 111. In the step of dispersing the colorant fine particles, the dispersion container 111 may have a jacket structure, and hot water or steam, and if necessary, cold water may flow in the jacket to control the temperature inside the dispersion container 111.

In the case of performing the dispersion treatment using the dispersion container shown in FIG. 3C, the direction in which the colorant is ejected from the stirring chamber of the stirring device 112 (the direction in which the colorant fine particles are ejected into the aqueous medium). Is preferably downward or in the horizontal direction. By jetting the colorant (colorant fine particles) downward or in the horizontal direction, the aqueous medium in the dispersion container 111 flows as shown by the arrow F. As a result, the colorant is jetted downward, and the flow flows along the wall. It rises and circulates again into Clearmix. Therefore, the dispersion step can be surely repeated, and the dispersion energy can be uniformly applied. As a result, it is presumed that the dispersion diameter and the like of the colorant can be made uniform. This makes it possible to efficiently form colorant fine particles having a sharp particle size distribution.

In the present invention, the dispersing machine used for the dispersion treatment of the colorant particles is, in addition to CLEARMIX, a pressure dispersing machine such as an ultrasonic dispersing machine, a mechanical homogenizer, a Menton-Gaulin, a pressure-type homogenizer, a getzman mill, and a diamond. A medium type disperser such as a fine mill can be used.

As described above, the colorant particles preferably used in the present invention are crushed by the action of the shearing force generated by the screen and the rotor, and the aggregated colorant particles are crushed to obtain a suitable average particle size (weight average particle size). : 30 to 500 nm) and sharp particle size distribution (standard deviation (σ): 30 or less)
A dispersion of colorant fine particles (fine particles close to primary particles) having the following formula is obtained. By subjecting such colorant fine particles (dispersed particles) to salting-out / fusion with resin fine particles, toner particles are formed. The colorant fine particles are surely introduced into the toner particles, the introduced colorant particles are not released, and there is no variation in the content of the colorant among the toner particles.

As a result, even when the toner of the present invention is subjected to image formation under high temperature and high humidity conditions or after a long period of non-use of the apparatus, image defects such as fogging and fine dot dust due to fluctuations in the charge amount of the toner can be prevented. It does not occur. Further, in the present invention, since the colorant fine particles are dispersed in the toner particles without using a medium, there is no occurrence of an image defect due to the residual fine impurities such as crushed pieces of the medium in the toner.

In order to carry out salting out / fusion of the composite resin particles and the colorant particles, a salting-out agent (aggregating agent) having a critical coagulation concentration or more is contained in a dispersion in which the composite resin particles and the colorant particles are dispersed. ) And heating the dispersion above the glass transition temperature (Tg) of the composite resin particles.

The preferable temperature range for salting out / fusing is (Tg + 10) to (Tg + 50 ° C.), and particularly preferably (Tg + 15) to (Tg + 40 ° C.). Further, in order to effectively perform the fusion, an organic solvent which is infinitely soluble in water may be added.

In the present invention, after the resin particles and the colorant are salted out, agglomerated and fused in an aqueous medium to obtain colored particles (in the present invention, referred to as toner particles), the toner particles are added to an aqueous medium. When separating from the medium, it is preferably carried out at a temperature not lower than the Kraft point of the surfactant present in the aqueous medium, more preferably at a temperature in the range of Kraft point to (Kraft point + 20 ° C). is there.

The above-mentioned Krafft point is a temperature at which an aqueous solution containing a surfactant starts to become cloudy, and the Krafft point is measured as follows.

<< Measurement of Kraft Point >> A solution was prepared by adding an actually used amount of a coagulant to an aqueous medium used in the steps of salting out, coagulation, and fusion, ie, a surfactant solution. For 5 days. The solution is then heated gradually with stirring until it becomes transparent. The temperature at which the solution becomes clear is defined as the Krafft point.

From the viewpoint of suppressing excessive charging of the toner particles and imparting a uniform charging property, in order to stabilize and maintain the charging property particularly with respect to the environment, the toner for developing an electrostatic image of the present invention comprises The above metal element (in the form of a metal, a metal ion or the like) may be added to the toner in an amount of 250 to 20,000.
ppm, more preferably 800 ppm
５5000 ppm.

In the present invention, the total value of the divalent (trivalent) metal element used for the coagulant and the monovalent metal element added as the coagulation terminator described later is 350 to 35,000 pp.
m is preferable. The measurement of the residual amount of metal ions in the toner is performed using a fluorescent X-ray analyzer "System 3270"
It can be determined by measuring the intensity of fluorescent X-rays emitted from a metal species of a metal salt used as a coagulant (for example, calcium derived from calcium chloride) using [Rigaku Denki Kogyo]. As a specific measuring method, a plurality of toners having a known content ratio of the coagulant metal salt are prepared, and 5 g of each toner is pelletized, and the content ratio (mass ppm) of the coagulant metal salt and the metal type of the metal salt are determined. The relationship (calibration curve) with the fluorescent X-ray intensity (peak intensity) from the sample is measured. Next, the toner (sample) whose content ratio of the coagulant metal salt is to be measured is similarly pelletized, and the fluorescent X-ray intensity from the metal species of the coagulant metal salt is measured. Quantity "can be determined. [Filtration / Washing Step] In this filtration / washing step, a filtration treatment for filtering out the toner particles from the dispersion of the toner particles obtained in the above step, and the filtered toner particles (cake-like aggregate) And a washing treatment for removing extraneous matter such as a surfactant and a salting-out agent. Here, the filtration method is not particularly limited, such as a centrifugal separation method, a reduced pressure filtration method using a Nutsche method, a filtration method using a filter press, or the like. [Drying Step] This step is a step of drying the washed toner particles.

[0165] Examples of the dryer used in this step include a spray dryer, a vacuum freeze dryer, and a reduced pressure dryer. A stationary shelf dryer, a movable shelf dryer, a fluidized bed dryer, a rotary bed dryer, It is preferable to use a type dryer, a stirring type dryer and the like.

The water content of the dried toner particles is preferably 5% by mass or less, more preferably 2% by mass or less.

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

The toner of the present invention forms composite resin particles in the absence of a colorant, adds a dispersion of the colorant particles to a dispersion of the composite resin particles, and mixes the composite resin particles with the colorant particles. It is preferably prepared by salting out / fusing.

As described above, by preparing the composite resin particles in a system in which no colorant is present, the polymerization reaction for obtaining the composite resin particles is not hindered. Therefore, according to the toner of the present invention, the excellent offset resistance is not impaired, and the fixing device is not stained or the image is not stained due to the accumulation of the toner.

Further, as a result of reliably performing the polymerization reaction for obtaining the composite resin particles, no monomer or oligomer remains in the obtained toner particles. No unpleasant odor is generated in the heat fixing step.

Further, the surface characteristics of the obtained toner particles are uniform and the charge amount distribution is sharp, so that an image having excellent sharpness can be formed for a long period of time. According to such a toner having a uniform composition, molecular weight, and surface characteristics among toner particles, good adhesion (high fixing strength) to an image support is maintained in an image forming method including a fixing step by a contact heating method. Meanwhile, the offset resistance and the anti-winding property can be improved, and an image having an appropriate gloss can be obtained.

Next, each component used in the toner manufacturing process will be described in detail. (Polymerizable monomer) As a polymerizable monomer for producing the resin (binder) used in the present invention, a hydrophobic monomer is an essential component, and a crosslinkable monomer is optionally used. Used. It is desirable that the structure contains at least one monomer having an acidic polar group or a monomer having a basic polar group as described below. (1) Hydrophobic monomer The hydrophobic monomer constituting the monomer component is not particularly limited, and a conventionally known monomer can be used. In addition, one kind or a combination of two or more kinds can be used so as to satisfy required characteristics.

Specifically, monovinyl aromatic monomers,
It is possible to use (meth) acrylate monomers, vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers, halogenated olefin monomers, and the like. it can.

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

Examples of (meth) acrylate monomers include acrylic acid, methacrylic acid, methyl acrylate,
Ethyl acrylate, butyl acrylate, acrylic acid-2
-Ethylhexyl, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, γ-aminopropyl acrylate, methacrylic acid Stearyl, dimethylaminoethyl methacrylate,
And diethylaminoethyl methacrylate.

Examples of the vinyl ester monomers include vinyl acetate, vinyl propionate, and vinyl benzoate. Examples of the vinyl ether monomers include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, and vinyl phenyl ether. And the like.

The monoolefin monomers include ethylene, propylene, isobutylene, 1-butene and 1-butene.
Examples thereof include pentene and 4-methyl-1-pentene, and examples of the diolefin-based monomer include butadiene, isoprene, and chloroprene. (2) Crosslinkable monomer A crosslinkable monomer may be added to improve the properties of the resin particles. Examples of the crosslinkable monomer include those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate. (3) Monomer having acidic polar group Examples of the monomer having an acidic polar group include (a) an α, β-ethylenically unsaturated compound having a carboxyl group (—COOH), and (b) a sulfone group. Α, β-ethylenically unsaturated compounds having (—SO ₃ H).

Α, β- having a carboxyl group of (a)
Examples of ethylenically unsaturated compounds include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid,
Examples thereof include cinnamic acid, monobutyl maleate, monooctyl maleate, and salts of these metals such as Na and Zn.

Examples of the (b) α, β-ethylenically unsaturated compound having a sulfone group include sulfonated styrene and its Na salt, allyl sulfosuccinic acid, allyl sulfosuccinate octyl, and these Na salts. Can be mentioned. (4) Monomer having a basic polar group Examples of the monomer having a basic polar group include (a) an amine group or a quaternary ammonium group having 1 to 1 carbon atoms.
2, preferably 2 to 8, particularly preferably 2, (meth) acrylic esters of aliphatic alcohols, (b) (meth)
Acrylamide or optionally 1 to 1 carbon atoms on N
(Meth) acrylic acid amide mono- or di-substituted with an alkyl group of 18, (c) a vinyl compound substituted with a heterocyclic group having N as a ring member, and (d) N, N-diallyl-alkylamine or A quaternary ammonium salt can be illustrated. Among them, (a) the aliphatic alcohol having an amine group or a quaternary ammonium group of (a)
Acrylic esters are preferred as monomers having a basic polar group.

Examples of the (meth) acrylate of an aliphatic alcohol having an amine group or a quaternary ammonium group (a) include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, Quaternary ammonium salts of four compounds, 3-dimethylaminophenyl acrylate, 2-hydroxy-
Examples thereof include 3-methacryloxypropyltrimethylammonium salt.

Examples of (b) (meth) acrylamide or (meth) acrylamide optionally mono- or dialkyl-substituted on N include acrylamide, N-butylacrylamide, N, N-dibutylacrylamide, piperidylacrylamide, Methacrylamide, N-butyl methacrylamide, N, N-dimethylacrylamide,
N-octadecylacrylamide and the like can be mentioned.

Examples of the vinyl compound (c) substituted by a heterocyclic group having N as a ring member include vinylpyridine, vinylpyrrolidone, vinyl-N-methylpyridinium chloride, vinyl-N-ethylpyridinium chloride and the like. Can be.

Examples of the N, N-diallyl-alkylamine (d) include N, N-diallylmethylammonium chloride, N, N-diallylethylammonium chloride and the like.

(Polymerization Initiator) The radical polymerization initiator used in the present invention can be appropriately used as long as it is water-soluble. For example, persulfates (eg, potassium persulfate, ammonium persulfate, etc.), azo compounds (eg, 4,4 ′)
-Azobis-4-cyanovaleric acid and salts thereof, 2,2'-azobis (2-amidinopropane) salts and the like), peroxide compounds and the like. Further, the above radical polymerization initiator can be used as a redox initiator in combination with a reducing agent, if necessary. Use of a redox-based initiator has preferred aspects such as an increase in polymerization activity, a reduction in polymerization temperature, and a reduction in polymerization time.

The polymerization temperature is not particularly limited as long as it is equal to or higher than the lowest radical generation temperature of the polymerization initiator, but is, for example, in the range of 50 ° C. to 90 ° C. However, by using a polymerization initiator that starts at room temperature in combination with a hydrogen peroxide-reducing agent (such as ascorbic acid), polymerization can be performed at room temperature or higher.

(Chain transfer agent) For the purpose of adjusting the molecular weight, a known chain transfer agent can be used. The chain transfer agent is not particularly limited, for example, octyl mercaptan, dodecyl mercaptan,
A compound having a mercapto group such as tert-dodecyl mercaptan is used. In particular, a compound having a mercapto group is preferably used because it suppresses odor at the time of heat-fixing, provides a toner having a sharp molecular weight distribution, and is excellent in storage stability, fixing strength, and offset resistance. Preferred are, for example, ethyl thioglycolate,
The mercapto group of propyl thioglycolate, propyl thioglycolate, butyl thioglycolate, t-butyl thioglycolate, 2-ethylhexyl thioglycolate, octyl thioglycolate, decyl thioglycolate, dodecyl thioglycolate, and ethylene glycol A compound having a mercapto group of neopentyl glycol and a compound having a mercapto group of pentaeristol. Among these, from the viewpoint of suppressing odor during toner heat fixing, n-octyl-
3-mercaptopropionate is particularly preferred.

(Surfactant) In order to perform miniemulsion polymerization using the above-mentioned polymerizable monomer, it is preferable to disperse oil droplets in an aqueous medium using a surfactant. Surfactants that can be used at this time are not particularly limited, but the following ionic surfactants can be mentioned as examples of suitable compounds.

Examples of the ionic surfactant include sulfonic acid salts (sodium dodecylbenzenesulfonate,
Sodium arylalkyl polyether sulfonate,
3,3-disulfonediphenylurea-4,4-diazo-
Sodium bis-amino-8-naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol -6
Sodium sulfonate), sulfate salts (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.),
Fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.) are exemplified.

In the present invention, surfactants represented by the following general formulas (1) and (2) are particularly preferably used. General formula (1) R ¹ (OR ² ) _n OSO ₃ M General formula (2) R ¹ (OR ² ) _n SO ₃ M In general formulas (1) and (2), R ¹ has 6 to 22 carbon atoms.
And preferably an alkyl group or an arylalkyl group having 8 to 20 carbon atoms, and more preferably an alkyl group or an arylalkyl group having 9 to 16 carbon atoms.

Examples of the alkyl group having 6 to 22 carbon atoms represented by R ¹ include n-hexyl group, n-heptyl group, n-octyl group, n-decyl group, n-undecyl group and n-hexadecyl. Group, cyclopropyl group, cyclopentyl group, cyclohexyl group, and the like, and the arylalkyl group represented by R ¹ includes a benzyl group, a diphenylmethyl group, a cinnamyl group, a styryl group, a trityl group, a phenethyl group, and the like. .

In the general formulas (1) and (2), R ² represents an alkylene group having 2 to 6 carbon atoms, preferably an alkylene group having 2 to 3 carbon atoms. Carbon atoms represented by R ² 2
Examples of the alkylene groups 6 to 6 include an ethylene group, a trimethylene group, a tetramethylene group, a propylene group, and an ethylethylene group.

In the general formulas (1) and (2), n is 1 to
It is an integer of 11, preferably 2 to 10, more preferably 2 to 5, and particularly preferably 2 to 3.

In the general formulas (1) and (2), examples of the monovalent metal element represented by M include sodium, potassium and lithium. Among them, sodium is preferably used.

Hereinafter, specific examples of the surfactant represented by the general formulas (1) and (2) will be shown, but the present invention is not limited thereto.

Compound (101): C ₁₀ H ₂₁ (OCH ₂ C
H ₂ ) ₂ OSO ₃ Na compound (102): C ₁₀ H ₂₁ (OCH ₂ CH ₂ ) ₃ OSO ₃
Na compound (103): C ₁₀ H ₂₁ (OCH ₂ CH ₂ ) ₂ SO ₃ N
a Compound (104): C ₁₀ H ₂₁ (OCH ₂ CH ₂ ) ₃ SO ₃ N
a Compound (105): C ₈ H ₁₇ (OCH ₂ CH (CH ₃ )) ₂
OSO ₃ Na compound (106): C ₁₈ H ₃₇ (OCH ₂ CH ₂ ) ₂ OSO ₃
In the present invention, from the viewpoint of maintaining the charge retention function of the toner in a good state, suppressing fogging under high temperature and high humidity, and improving transferability, and suppressing an increase in charge amount under low temperature and low humidity, From the viewpoint of stabilizing the development amount, the content of the surfactant represented by the general formulas (1) and (2) in the toner for developing an electrostatic image is preferably from 1 to 1000 ppm, more preferably from 1 to 1000 ppm. It is 5 to 500 ppm, particularly preferably 7 to 100 ppm.

In the present invention, by setting the amount of the surfactant to be contained in the toner within the above-mentioned range, the chargeability of the toner for developing an electrostatic image of the present invention is always affected by the influence of the environment. , Can be applied and maintained in a uniform and stable state.

Further, the content of the surfactant represented by the above general formulas (1) and (2) contained in the toner for developing an electrostatic image of the present invention is calculated by the following method. .

1 g of the toner is dissolved in 50 ml of chloroform, and the surfactant is extracted from the chloroform layer with 100 ml of ion-exchanged water. The extracted chloroform layer was extracted again with 100 ml of ion-exchanged water to obtain a total of 200 ml of an extract (aqueous layer).
Dilute to 00 ml.

This diluent was used as a test solution in accordance with JIS 33
According to the method specified in Section 636, the color is developed with methylene blue, the absorbance is measured, and the content of the surfactant in the toner is measured from a separately prepared calibration curve.

The structures of the surfactants represented by the general formulas (1) and (2) were determined by analyzing the above extract using 1H-NMR.

In the present invention, a metal salt can be preferably used as a coagulant in the step of salting out, coagulating, and fusing resin particles from a dispersion of resin particles prepared in an aqueous medium. More preferably, a trivalent metal salt is used as a flocculant. The reason is that a divalent or trivalent metal salt is preferable to a monovalent metal salt because the critical aggregation concentration (coagulation value or coagulation point) is smaller.

In the present invention, nonionic surfactants can also be used. Specific examples include polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, an ester of polyethylene glycol and a higher fatty acid, and an alkylphenol. Examples include polyethylene oxide, esters of higher fatty acids and polyethylene glycol, esters of higher fatty acids and polypropylene oxide, and sorbitan esters.

In the present invention, these surfactants are mainly used as an emulsifier at the time of emulsion polymerization, but may be used for other steps or other purposes.

(Molecular Weight Distribution of Resin Particles and Toner) The toner of the present invention has a molecular weight distribution peak or shoulder of 10%.
0.00-1,000,000, and 1,000-5
It is preferable that the peak is present at a molecular weight distribution of 100,000 to 1,000,000.
0, 25,000 to 150,000 and 1,000 to 5
It is preferably present at 0,000.

The molecular weight of the resin particles is from 100,000 to
A resin containing at least a high molecular weight component having a peak or shoulder in a region of 1,000,000 and a low molecular weight component having a peak or shoulder in a region of 1,000 to less than 50,000 is preferable, and more preferably a resin. Is
It is preferable to use an intermediate molecular weight resin having a peak or shoulder at a portion of 15,000 to 100,000.

The above-mentioned method for measuring the molecular weight of the toner or the resin is based on the GP using THF (tetrahydrofuran) as a solvent.
Measurement by C (gel permeation chromatography) is good. That is, 1.0 ml of THF is added to 0.5 to 5 mg, more specifically, 1 mg of a measurement sample, and the mixture is stirred at room temperature using a magnetic stirrer or the like to be sufficiently dissolved. Then, pore size 0.45
After treatment with a 0.50 μm membrane filter,
Inject into GPC. GPC measurement conditions are as follows: stabilize the column at 40 ° C., flow THF at a flow rate of 1.0 ml per minute, and inject about 100 μl of a 1 mg / ml concentration sample for measurement. The column is preferably used in combination with a commercially available polystyrene gel column. For example, Shodex GPC KF-801, 80 manufactured by Showa Denko KK
2, 803, 804, 805, 806, 807 and TSKgel G1000H, G200 manufactured by Tosoh Corporation
0H, G3000H, G4000H, G5000H, G
6000H, G7000H, TSK guard co
and the like. As the detector, a refractive index detector (IR detector) or U
Preferably, a V detector is used. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve created using monodispersed polystyrene standard particles. It is preferable to use about 10 polystyrenes for preparing a calibration curve.

(Aggregating Agent) In the present invention, a metal salt can be preferably used as an aggregating agent in the step of salting out, aggregating, and fusing resin particles from a dispersion of resin particles prepared in an aqueous medium. It is further preferable to use a divalent or trivalent metal salt as a flocculant. The reason is that a divalent or trivalent metal salt is preferable to a monovalent metal salt because the critical aggregation concentration (coagulation value or coagulation point) is smaller.

The coagulant used in the present invention is, for example, a monovalent metal salt which is a salt of an alkali metal such as sodium, potassium or lithium, for example, a salt of an alkaline earth metal such as calcium or magnesium, or a manganese or copper salt. Examples thereof include divalent metal salts and trivalent metal salts such as iron and aluminum.

Specific examples of these metal salts are shown below.
Examples of the monovalent metal salt include sodium chloride, potassium chloride, and lithium chloride. Examples of the divalent metal salt include calcium chloride, zinc chloride, copper sulfate, magnesium sulfate, and manganese sulfate. Examples thereof include aluminum chloride and iron chloride. These are appropriately selected depending on the purpose, but are preferably divalent or trivalent metal salts having a low critical aggregation concentration.

The critical coagulation concentration in the present invention is an index relating to the stability of a dispersion in an aqueous dispersion, and indicates the concentration of the coagulant added when a coagulant is added and coagulation occurs. This critical aggregation concentration varies greatly depending on the latex itself and the dispersant. For example, it is described in Seizo Okamura et al., Polymer Chemistry 17, 601 (1960).
According to these descriptions, the value can be known.
As another method, a desired salt is added to the target particle dispersion at a different concentration, and the ζ potential of the dispersion is measured.
ζIt is also possible to set the salt concentration at the point where the potential starts to change as the critical aggregation concentration.

In the present invention, the polymer fine particle dispersion is treated using a metal salt so as to have a concentration equal to or higher than the critical aggregation concentration. At this time, of course, add the metal salt directly,
The addition as an aqueous solution is arbitrarily selected depending on the purpose. In the case of adding as an aqueous solution, the added metal salt needs to be at or above the critical aggregation concentration of the polymer particles with respect to the volume of the polymer particle dispersion and the total volume of the metal salt aqueous solution.

In the present invention, the concentration of the metal salt may be not less than the critical coagulation concentration, but is preferably not less than 1.
It is added twice or more, more preferably 1.5 times or more.

(Colorant) The toner of the present invention is obtained by salting out / fusing the composite resin particles and the colorant particles. As the colorant (colorant particles subjected to salting-out / fusion with the composite resin particles) constituting the toner of the present invention, organic pigments are usually preferably used as described above. Inorganic pigments and dyes are also used, and are not necessarily limited to only organic pigments.

As the inorganic pigment, conventionally known ones can be used. Specific examples of the inorganic pigment include black pigments such as furnace black, channel black, acetylene black, thermal black and lamp black. Magnetic powders such as black, magnetite, and ferrite may also be used.

These inorganic pigments can be used alone or in combination of two or more as desired. The amount of the pigment to be added is 2 to 20% by mass, preferably 3 to 15% by mass, based on the polymer.

When used as a magnetic toner, the above-mentioned magnetite can be added. In this case, from the viewpoint of imparting predetermined magnetic characteristics, 20 to 6
It is preferable to add 0% by mass. These inorganic pigments may be in the form of a water-wet colorant paste.

As the organic pigments and dyes, conventionally known organic pigments and dyes can be used, and the use of a water-wet colorant paste is more effective according to the present invention, as described above. Specific organic pigments are exemplified below.

The pigments for magenta or red include:
For example, C.I. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I.
Pigment Red 6, C.I. I. Pigment Red 7,
C. I. Pigment Red 15, C.I. I. Pigment Red 16, C.I. I. Pigment Red 48: 1, C.I.
I. Pigment Red 53: 1, C.I. I. Pigment Red 57: 1, C.I. I. Pigment Red 122, C.I.
I. Pigment Red 123, C.I. I. Pigment Red 139, C.I. I. Pigment red 144, C.I. I.
Pigment Red 149, C.I. I. Pigment Red 1
66, C.I. I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 222
And the like.

Examples of orange or yellow pigments include C.I. I. Pigment Orange 31, C.I.
I. Pigment Orange 43, C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 13, C.I. I.
Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 9
4, C.I. I. Pigment yellow 138, C.I. I. Pigment yellow 180, C.I. I. Pigment Yellow 1
85, C.I. I. Pigment yellow 155, C.I. I. Pigment Yellow 156 and the like.

The green or cyan pigments include
For example, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 1
5: 3, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 60, C.I. I. Pigment Green 7 and the like.

Examples of the dye include C.I. I. Solvent Red 1, 49, 52, 58, 63
111, 122, C.I. I. Solvent Yellow 1
9, 44, 77, 79, 81, 82, 9
3, 98, 103, 104, 112, 16
2, C.I. I. Solvent Blue 25, 36, 60
70, 93, 95 and the like can be used, and a mixture thereof can also be used.

These organic pigments and dyes can be used alone or in combination of two or more as desired.
The amount of the pigment added is 2 to 20% by mass based on the polymer.
And preferably 3 to 15% by mass.

(Crystalline substance) The toner used in the present invention is obtained by fusing resin particles containing a crystalline substance in an aqueous medium, and forming a sea-island structure by appropriately aggregating the crystalline substance by an aging step. It is preferable that the toner is a dried toner. By salting out / fusing the resin particles containing the crystalline substance in the resin particles with the colorant particles in the aqueous medium, a toner in which the crystalline substance is finely dispersed can be obtained. Here, the aging step refers to a step of continuing stirring at a temperature within the range of the melting point of the crystalline substance ± 20 ° C. even after the fusion of the resin particles.

In the toner of the present invention, low molecular weight polypropylene (number average molecular weight = 1500 to 9000), low molecular weight polyethylene, or the like is preferable as the crystalline substance having a releasing function, and particularly preferable is an ester represented by the following formula. It is a system compound.

R _1- (OCO-R ₂ ) _{n In the} formula, n is an integer of 1 to 4, preferably 2 to 4, more preferably 3 to 4, and particularly preferably 4. R ₁ , R
₂ represents a hydrocarbon group which may have a substituent. R ₁
Has 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, and more preferably 2 to 5 carbon atoms. R ₂ has 1 to 40 carbon atoms, preferably 16 to 30 carbon atoms, and more preferably 18 to 26 carbon atoms.

Next, examples of typical compounds are shown below.

[0227]

Embedded image

[0228]

Embedded image

In the present invention, a crystalline polyester can also be used as the crystalline substance. Examples of the crystalline polyester include aliphatic diols and aliphatic dicarboxylic acids (including acid anhydrides and acid chlorides). ) Is preferred.

The diol used for obtaining the crystalline polyester includes ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol,
4-butanediol, 1,4-butenediol, neopentyl glycol, 1,5-pentane glycol, 1,
6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, bisphenol Z, hydrogenated bisphenol A, and the like. it can.

The dicarboxylic acids used for obtaining the crystalline polyester include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, speric acid, azelaic acid, sebacic acid, maleic acid, fumaric acid , Citraconic acid, itaconic acid, glutacoic acid, n-dodecylsuccinic acid, n-dodecenylsuccinic acid, isododecylsuccinic acid, isododecenylsuccinic acid, n-octylsuccinic acid, n-octenylsuccinic acid, these acid anhydrides or Acid chlorides can be mentioned.

Particularly preferred crystalline polyesters include polyester obtained by reacting 1,4-cyclohexanedimethanol with adipic acid, polyester obtained by reacting 1,6-hexanediol with sebacic acid, and ethylene glycol. And succinic acid, polyester obtained by reacting ethylene glycol and sebacic acid, and polyester obtained by reacting 1,4-butanediol and succinic acid. Among them, a polyester obtained by reacting 1,4-cyclohexanedimethanol with adipic acid is most preferred.

The addition amount of the above compound is 1 to 30% by mass, preferably 2 to 20% by mass, more preferably 3 to 15% by mass based on the whole toner.

(Developer) The toner of the present invention may be used as a one-component developer or a two-component developer. When the toner is used as a one-component developer, it may be used in a non-magnetic one-component developer or in a toner. A magnetic one-component developer containing magnetic particles of about 1 to 0.5 μm can be used, and any of them can be used.

Further, it can be mixed with a carrier and used as a two-component developer. In this case, as the magnetic particles of the carrier, metals such as iron, ferrite and magnetite, and metals such as aluminum and lead are used. A conventionally known material such as an alloy of the above can be used. Particularly, ferrite particles are preferable. The magnetic particles have a volume average particle size of 15 to 100 μm, more preferably 25 to 80 μm.
μm is preferred.

The volume average particle size of the carrier is typically measured by a laser diffraction type particle size distribution analyzer “HELOS” equipped with a wet disperser (SYMPATIC (SYMPIC)
(ATEC)).

The carrier is preferably a carrier in which magnetic particles are further coated with a resin, or a so-called resin-dispersed carrier in which magnetic particles are dispersed in a resin. The resin composition for coating is not particularly limited, but, for example, an olefin resin, a styrene resin, a styrene-acrylic resin, a silicone resin, an ester resin, or a fluorine-containing polymer resin is used. The resin for forming the resin dispersion type carrier is not particularly limited, and a known resin can be used. For example, a styrene-acrylic resin, a polyester resin, a fluororesin, a phenol resin, or the like is used. be able to.

Next, an image forming apparatus used in the image forming method using the toner of the present invention will be described.

In the present invention, an electrostatic latent image formed by performing charging and image exposure on a photosensitive member is developed with a developer, and a toner image formed is transferred to a transfer material using a contact transfer method. Repeat each process of separation, fixing and cleaning,
A large number of images are formed.

(Transfer Roll) The transfer of the toner image from the photoreceptor surface to the transfer material is performed by elastically pressing the transfer roll against the photoreceptor and applying a bias voltage to the toner image. As the transfer roll, an elastic body made of rubber, a porous foam, or the like is used. For example, (1) Bridgestone's ionic conductive type, (2) Bridgestone's electronic conductive type, (3) Toyo Polymer's urethane foam rubycell type, (4) Sumitomo Rubber Industries' ionic conductive type, (5) Sumitomo EPDM type manufactured by Rubber Industry Co., Ltd., (6) Epichlorohydrin type manufactured by Sumitomo Rubber Industries Co., Ltd., (7) ENDUR manufactured by Inoac Corporation
(8) Foamed silicone type manufactured by Tigers Polymer, (9) Urethane foamed type manufactured by Hokushin Kogyo Co., Ltd., (10) Foamed silicone type manufactured by Shin-Etsu Polymer Co., Ltd. And other types of transfer rolls, and preferably a foam type.

In the image forming method used in the present invention, in order to transfer the toner image on the photoreceptor surface to the transfer material satisfactorily, the pressing force of the transfer roll against the photoreceptor is 2.5 to 1
00 kPa is preferable, and more preferably 10 to 80 kP.
a.

When the pressing force is 2.5 to 100 kPa, the transfer of the toner image becomes sufficient, and the transfer of a releasable crystalline substance in the toner to the surface of the photoreceptor can be prevented. The occurrence of defects can also be prevented. In addition, the impact at the time of releasing the pressure of the transfer roll is reduced, so that an image defect due to a transfer deviation can be prevented, and damage to the photoconductor can be prevented.

As the characteristics required for the transfer roll, for example, rebound resilience, electric resistance, surface hardness and the like are important. The rebound resilience of the elastic body of the transfer roll is preferably 30 to 70%. When the rebound resilience is 30 to 70%, a sufficient pressing force to the photoreceptor for transferring a toner image is obtained, so that a good transfer rate is obtained.
Further, since the impact at the time of transfer can be reduced, occurrence of image defects such as transfer deviation can be prevented. The rebound resilience is J
It is measured by the measuring method of IS K7311.

The transfer roll needs to have an appropriate conductivity to enable application of a bias voltage for transferring a toner image, and has an electric resistance of 1 as measured by the following measuring method.
It is preferably from × 10 ³ to 1 × 10 ¹³ Ω.

Measurement method: 4 m thick on a rotating shaft having a diameter of 16 mm and a length of 310 mm
The transfer roll provided with an elastic body of m is pressed against an aluminum tube having a diameter of 30 mm with a force of 17 kPa.
Under an environment of% RH, an electric resistance value between the rotation axis of the transfer roll and the aluminum tube is measured.

The elastic body preferably has a surface hardness of 20 to 70 degrees as measured by Asker C hardness tester. A transfer roll made of an elastic material having a Asker C hardness of 20 to 70 degrees is preferable because transfer is properly performed and image defects such as transfer deviation do not occur.

Next, an image forming apparatus used in the image forming method for forming a large number of images according to the present invention will be described. Note that the image forming method for forming a large number of images according to the present invention refers to a method of forming an electrostatic latent image formed by performing charging and image exposure on a photoreceptor, using a developer containing a toner for developing an electrostatic latent image. The image forming method is to transfer a toner image developed and formed on the transfer material to a transfer material by using a contact transfer method, and thereafter to repeat a process of separating, fixing and cleaning to form a large number of images.

FIG. 4 is a schematic diagram showing an example of an image forming apparatus using a transfer roll. Referring to FIG.
Is an organic photoreceptor that rotates in the direction of the arrow, 11 is a charger for uniformly charging the photoreceptor, and the charger may be a corona discharger, a roller charger, or a magnetic brush charger. . Reference numeral 12 denotes digital image exposure light using a semiconductor laser, a light emitting diode, or the like, and an electrostatic latent image is formed on the photoconductor by the image exposure light. This electrostatic latent image is developed in a contact or non-contact manner by a developing device 13 containing a developer containing a toner having a volume average particle diameter of 3 to 9 μm, and a toner image is formed on the photoconductor. In the image formation using the toner of the present invention, digital image exposure is particularly preferable, but analog image exposure may be performed.

As a scanning optical system that modulates light with a digital image signal from a computer or a copy original used in the image forming method and apparatus, an acousto-optic modulator is interposed in a laser optical system, and the acousto-optic modulator uses the acousto-optic modulator. There is a device for modulating the light and a device for directly modulating the laser intensity using a semiconductor laser. These scanning optical systems form a dot-like image by spot exposure on a uniformly charged photoconductor.

The beam emitted from the above-described scanning optical system has a round or elliptical luminance distribution approximating a normal distribution with a skirt spreading left and right. One or both of the scanning direction and the sub-scanning direction has an extremely narrow round or elliptical shape of 20 to 100 μm.

The toner image is transferred onto the transfer material P conveyed in a timely manner by the transfer roll 15 at a pressing force of 2.5 to 100 kPa, preferably 10 to 80 kPa, on the photosensitive member under the application of a DC bias.

The DC bias power supply 16 for applying a bias to the transfer roll 15 is preferably a constant current power supply or a constant voltage power supply. In the case of the constant current power supply, 5 to 15 μA
In the case of a constant voltage power supply, the absolute value is 400 to 1500.
V. The transfer material P on which the image has been transferred by the transfer roll 15 is separated from the photoreceptor 10 by the separation pole 14 and is conveyed to a fixing device (not shown) to be heated and fixed.

The surface of the photoreceptor after the transfer is cleaned by a cleaning blade 17 and then discharged by a discharge lamp (PCL) 18 to prepare for the next image formation. Reference numeral 19 denotes a paper feed roller, and reference numeral 20 denotes a fixing device.

(Intermediate Transfer Body) In the present invention, the transfer of the toner image from the photoreceptor to the transfer material can be performed by a method using an intermediate transfer body. That is, an image forming unit (image forming unit) is provided for each of the four color developers, and in each image forming unit, a visible image of each color is formed on each photoconductor, and these visible images are sequentially transferred to an intermediate transfer body. After a batch transfer to a transfer material (usually plain paper, but there is no particular limitation as long as it can be transferred. In particular, in the present invention, an OHP sheet is preferable as the transfer material), and after fixing, a color image is formed. It can also be preferably used for the method of obtaining.

An image forming method in which a plurality of color images used in an image forming apparatus using the toner of the present invention are formed in an image forming section, and the images are successively superimposed and transferred onto the same intermediate transfer member is shown in FIG. It will be described based on the following. FIG. 5 is a schematic configuration diagram illustrating an example of an image forming apparatus using an intermediate transfer member (transfer belt).

In FIG. 5, the image forming apparatus for obtaining a color image includes a plurality of image forming units, each of which forms a visible image (toner image) having a different color, and forms the toner image. This is an image forming method in which the images are sequentially transferred onto the same intermediate transfer member.

Here, first, second, third and fourth image forming units Pa, Pb, Pc and Pd are provided side by side, and each of the image forming sections is a photosensitive element which is an electrostatic latent image forming body. It has bodies 1a, 1b, 1c and 1d. The photoconductors 1a, 1b, 1c, and 1d have a latent image forming section
a, 2b, 2c and 2d, developing units 3a, 3b, 3c and 3d, transfer discharge units 4a, 4b, 4c and 4d, a cleaning device 5 having a cleaning member and a rubber blade
a, 5b, 5c and 5d, and chargers 6a, 6b, 6c and 6d.

With such a configuration, first, a latent image of, for example, a yellow component color in a document image is formed on the photoreceptor 1a of the first image forming unit Pa by the latent image forming section 2a. The latent image is converted into a visible image by the developer containing the yellow toner in the developing unit 3a, and is transferred to the transfer belt 21 by the transfer discharging unit 4a.

On the other hand, while the yellow toner image is being transferred to the transfer belt 21 as described above, a magenta component color latent image is formed on the photoreceptor 1b in the second image forming unit Pb. At 3b, a visible image is formed with a developer containing a magenta toner. This visible image (magenta toner image) is transferred onto the transfer belt 21 at a predetermined position when the transfer belt, which has been transferred by the first image forming unit Pa, is carried into the transfer discharge unit 4b. You.

Hereinafter, the third and fourth steps are performed in the same manner as described above.
The image forming units Pc and Pd form an image of a cyan component color and a black component color, and a cyan toner image and a black toner image are transferred onto the same transfer belt in a superimposed manner. When such an image forming process is completed, a multicolor superimposed image is obtained on the transfer belt 21. On the other hand, each of the photoconductors 1a, 1b, 1c and 1d after the transfer is completed, the residual toner is removed by the cleaning devices 5a, 5b, 5c and 5d, and the photoconductors 1a, 1b, 5c and 5d are provided for the subsequent latent image formation.

In the image forming apparatus, the transfer belt 21 is used.
Is transported from the right side to the left side, and in the transporting process, passes through the transfer discharge sections 4a, 4b, 4c and 4d in the image forming units Pa, Pb, Pc and Pd, and the color transfer images are transferred.

If the transfer belt 21 is in the fourth image forming unit P
When the voltage passes d, the AC voltage is applied to the separation / discharge discharger 22d, the transfer belt 21 is discharged, and the toner image is collectively transferred onto the transfer material P. Thereafter, the transfer material P enters the fixing device 23, is fixed, is discharged from the discharge port 25, and a color image is obtained.

[0263] Reference numerals 22a, 22b, 22c and 22d in the figure denote separation / discharge dischargers. The transfer belt 21 after the transfer of the toner image is cleaned by a cleaning device 24 using both a brush-like cleaning member and a rubber blade. The transfer residual toner is cleaned and prepared for the next image formation.

As described above, even when a multi-color superimposed image is formed on a long transfer belt 21 such as a conveyor belt and the multi-color superimposed image is collectively transferred to a transfer material, the image is A configuration may be employed in which the forming units are provided with independent transfer belts, and then transfer is sequentially performed from each transfer belt to a transfer material.

As the transfer belt, for example, a polyimide, polyether, polyamide or tetrafluoroethylene / perfluorovinyl ether copolymer having a surface resistance of at least 10 ¹⁴ Ω and a high-resistance film having a thickness of about 20 μm may be used. The surface resistance is adjusted to 10 ⁵ to 10 ⁸ Ω by adding a conductive agent to a fluorine-based or silicon-based resin.
An endless film provided with a release layer having a thickness of 5 μm is used.

In the image forming method using the toner of the present invention, the toner image formed in the developing step is fixed in the fixing step through the step of transferring to a transfer material as described above. As a suitable fixing method used in the present invention, a so-called contact heating method can be used. In particular, as the contact heating method, there are a heat pressure fixing method, a hot roll fixing method, and a pressure contact heat fixing method in which fixing is performed by a rotating pressing member including a fixedly disposed heating element.

In the hot roll fixing method, an upper roller having a heat source inside a metal cylinder made of iron, aluminum, or the like, the surface of which is coated with tetrafluoroethylene or polytetrafluoroethylene-perfluoroalkoxyvinyl ether copolymer, is used. And a lower roller made of silicone rubber or the like. The heat source has a linear heater, and the surface temperature of the upper roller is set to 120 to
Heating to about 200 ° C. is a typical example. In the fixing section, pressure is applied between the upper roller and the lower roller to deform the lower roller and form a so-called nip. The nip width is 1 to 10 mm, preferably 1.5 to 7 mm. Fixing linear speed is 40mm / sec-600mm / sec
c is preferred. When the nip is narrow, heat cannot be uniformly applied to the toner, causing uneven fixing. On the other hand, if the nip width is wide, the melting of the resin is promoted, and a problem occurs in that the fixing offset becomes excessive.

A fixing cleaning mechanism may be provided for use. As this method, a method in which a silicone oil is supplied to a roller or a film after fixing, or a method in which a silicone oil-impregnated pad, roller, web or the like is used for cleaning can be used.

Next, a description will be given of a method of fixing by a rotating pressing member including a fixedly disposed heating element used in image formation using the toner of the present invention.

This fixing system is a system in which a heating member fixedly arranged is pressed and heated and fixed by a pressing member which is opposed to and pressed against the heating member and makes a transfer material adhere to the heating member via a film.

In this press-contact heating fixing device, the heating element has a smaller heat capacity than a conventional heating roller, and has a linear heating section in a direction perpendicular to the direction in which the transfer material passes. Is 100 to 300 ° C.

[0272] The press-contact heat-fixing is performed by pressing an unfixed toner image against a heating source to fix the image, as in a method in which a transfer material containing unfixed toner passes between a heating member and a pressing member. Is the way. Such a measure allows the heating to be carried out quickly, so that the fixing can be performed at high speed.However, the temperature control is difficult, and the toner adheres and remains on a portion where the unfixed toner is directly pressed against, such as the surface of the heating source. That is, there is a problem that a so-called toner offset easily occurs, and a failure such as the winding of the transfer material around the fixing device easily occurs.

In this fixing method, the low-heat-capacity linear heating body fixedly supported by the apparatus has a thickness of 0.2 to 5.0 mm.
0 mm, more preferably 0.5 to 3.5 mm and width 10
A resistance material is applied to an alumina substrate having a length of 240 to 400 mm and a length of 240 to 400 mm, and is supplied with electricity from both ends.

The energization is performed at a cycle of 15 to 25 m at 100 V DC.
The pulse waveform is given by changing the pulse width according to the temperature / energy release amount controlled by the temperature sensor with a pulse waveform of sec. In the case of the temperature T1 detected by the temperature sensor in the low heat capacity linear heating element, the surface temperature T2 of the film facing the resistance material is lower than T1. Here, T1 is preferably 120 to 220 ° C., and the temperature of T2 is preferably 0.5 to 10 ° C. lower than the temperature of T1. Further, the film material surface temperature T3 at a portion where the film is separated from the toner surface is substantially equal to T2. The film moves in the direction of the center arrow in FIG. 6A by contacting the heating element whose energy and temperature are controlled in this manner. These fixing films include heat-resistant films having a thickness of 10 to 35 μm, for example, polyesters, polyperfluoroalkoxy vinyl ethers, polyimides, and polyetherimides, and in many cases, fluororesins such as Teflon (R) and conductive materials. And a release agent layer coated with 5 to 15 μm.

In driving the film, a driving force and a tension are applied by a driving roller and a driven roller, and the film is transported in the direction of the arrow without wrinkles and twists. The linear velocity of the fixing device is preferably 230 to 900 mm / sec.

The pressure roller has a rubber elastic layer such as silicone rubber with high releasability, is pressed against a heating body via a film material, and rotates by pressing.

In the above description, an example using an endless film has been described. However, as shown in FIG. Good. Further, it may be a simple cylindrical member having no drive roller or the like inside.

The fixing device may be provided with a cleaning mechanism. As a cleaning method, a method of supplying various silicone oils to the fixing film or a method of cleaning with a pad, a roller, a web, or the like impregnated with various silicone oils is used.

As the silicone oil, polydimethylsiloxane, polymethylphenylsiloxane, polydiphenylsiloxane and the like can be used. Further, fluorine-containing siloxane can also be suitably used.

Next, FIG. 6 shows an example of a sectional view of the structure of this fixing device. In FIG. 6A, reference numeral 84 denotes a low-heat-capacity linear heating body fixedly supported by the apparatus. As an example, a resistance material 86 is attached to an alumina substrate 85 having a height of 1.0 mm, a width of 10 mm, and a length of 240 mm. Is applied to a width of 1.0 mm, and electricity is supplied from both ends in the longitudinal direction.

The energization is performed, for example, at a DC voltage of 100 V, usually in a pulse-like waveform with a period of 20 msec, and is controlled by a signal from the temperature detecting element 87 to maintain a predetermined temperature.
For this reason, the pulse width is changed in accordance with the energy release amount, and the range is, for example, 0.5 to 5 msec. The transfer material 94 carrying the unfixed toner image 93 is brought into contact via the film 88 moved to the heating member 84 controlled in this way, and the toner is thermally fixed.

The film 88 used here moves without generating wrinkles while being tensioned by the driving roller 89 and the driven roller 90. Reference numeral 95 denotes a pressure roller having a rubber elastic layer formed of silicone rubber or the like, and presses the heating body through the film at a total pressure of 0.4 to 2.0 N. Unfixed toner image 93 on transfer material 94
Are guided to the fixing section by the entrance guide 96, and a fixed image is obtained by the above-described heating.

Although the endless belt has been described above, as shown in FIG. 6 (b), a film sheet feeding shaft 91 and a winding shaft 92 may be used, and an endless fixing film may be used.

Further, the image forming apparatus used in the present invention may have a mechanism for recycling toner by recycling untransferred toner remaining on the surface of the photoreceptor. The method for recycling the toner is not particularly limited.For example, the toner collected in the cleaning unit is mixed with a toner hopper for replenishment, a developing device, or toner for replenishment by a transport conveyor or a transport screw by an intermediate chamber. To the developing device. Preferably, a method of directly returning the toner to the developing device or a method of mixing and supplying the replenishment toner and the recycled toner in the intermediate chamber can be used.

Next, FIG. 7 shows an example of a perspective configuration diagram of a toner recycling member. In this method, the recycled toner is directly returned to the developing device.

The untransferred toner collected by the cleaning blade 130 is collected in a toner recycling pipe 140 by a transport screw in the toner cleaning device 110, and is returned to the developing device 600 from a receiving port 150 of the recycling pipe, and is again used as a developer. used.

FIG. 7 is also a perspective view of a process cartridge detachable from the image forming apparatus used in the present invention. In FIG. 7, the photoreceptor unit and the developer unit are separated so that the perspective structure can be easily understood, but they can be removably mounted as an integrated unit in the image forming apparatus. In this case, the photoconductor, developing device,
The cleaning device and the recycling member are integrated to form a process cartridge.

[0288]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto. In the description, “parts” means “parts by mass”.

Production Example of Resin Particles for Toner [Latex 1HML] (1) Preparation of core particles (first stage polymerization): A 5000 ml separable flask equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introducing device was placed in a flask. Anionic surfactant (101) A surfactant solution (aqueous medium) prepared by dissolving 7.08 g of C ₁₀ H ₂₁ (OCH ₂ CH ₂ ) ₂ OSO ₃ Na in 3010 g of ion-exchanged water is charged, and is charged under a nitrogen stream at 230 r.
While stirring at a stirring speed of pm, the internal temperature was raised to 80 ° C.

To this surfactant solution were added 9.2 g of a polymerization initiator (potassium persulfate: KPS) and 200 g of ion-exchanged water.
Was added, and the temperature was adjusted to 75 ° C., and then 70.1 g of styrene and n-butyl acrylate 1 were added.
A monomer mixture consisting of 9.9 g and 10.9 g of methacrylic acid was added dropwise over 1 hour, and the system was heated and stirred at 75 ° C. for 2 hours to perform polymerization (first-stage polymerization). Latex (a dispersion of resin particles composed of a high molecular weight resin) was prepared. This is designated as “latex (1H)”. (2) Formation of intermediate layer (second stage polymerization): In a flask equipped with a stirrer, 105.6 g of styrene and n-
30.0 g of butyl acrylate, 6.2 methacrylic acid
g, a compound represented by the above formula (19) as a crystalline substance (hereinafter referred to as “exemplary compound (19)”) in a monomer mixture comprising 5.6 g of n-octyl-3-mercaptopropionate. 98.0 g were added and 90 ° C.
Was heated and dissolved to prepare a monomer solution.

On the other hand, an anionic surfactant (formula (1)
01)) A surfactant solution obtained by dissolving 1.6 g in 2700 ml of ion-exchanged water was heated to 98 ° C., and the latex (1H) as a dispersion of core particles was added to the surfactant solution.
Was added in an amount of 28 g in terms of solid content, and then a mechanical dispersing machine having a circulation route “CLEARMIX”
The monomer solution of Exemplified Compound (19) was mixed and dispersed for 8 hours by (M Technique Co., Ltd.), and a dispersion liquid (emulsion liquid) containing emulsified particles (oil droplets) having a dispersed particle diameter (284 nm) was obtained. ) Was prepared.

Next, to this dispersion liquid (emulsion liquid), an initiator solution obtained by dissolving 5.1 g of a polymerization initiator (KPS) in 240 ml of ion-exchanged water and 750 ml of ion-exchanged water were added. Polymerization (second-stage polymerization) is carried out by heating and stirring at 12 ° C. for 12 hours, and latex (a dispersion of composite resin particles having a structure in which the surface of resin particles made of a high molecular weight resin is coated with an intermediate molecular weight resin) is used. Obtained. This is referred to as “latex (1HM)”.

The latex (1HM) was dried and observed with a scanning electron microscope. As a result, particles (4) containing the exemplified compound (19) as a main component and not surrounded by the latex were observed.
00-1000 nm) was observed. (3) Formation of outer layer (third stage polymerization): A polymerization initiator (KPS) is added to the latex (1HM) obtained as described above.
An initiator solution in which 7.4 g was dissolved in 200 ml of ion-exchanged water was added, and styrene 300 was dissolved under a temperature condition of 80 ° C.
g, n-butyl acrylate 95 g, methacrylic acid 1
A monomer mixture composed of 5.3 g and 10.4 g of n-octyl-3-mercaptopropionate was added dropwise over 1 hour. After completion of the dropping, polymerization (third-stage polymerization) is carried out by heating and stirring for 2 hours, and then cooled to 28 ° C. to form a latex (a central portion composed of a high molecular weight resin, an intermediate layer composed of an intermediate molecular weight resin, A dispersion of composite resin particles having an outer layer made of a molecular weight resin and the intermediate layer containing the exemplified compound (19). This latex is referred to as “latex (1HML)”.

The composite resin particles constituting this latex (1HML) were 138,000, 80,000 and 1
It has a peak molecular weight of 3,000,
The weight average particle size of the composite resin particles was 122 nm. [Latex 2 L] In a flask equipped with a stirrer, 14.8 g of a polymerization initiator (KPS) was added to ion-exchanged water 4.
The initiator solution dissolved in 00 ml was charged, and under a temperature condition of 80 ° C., 600 g of styrene, 190 g of n-butyl acrylate, 30.0 g of methacrylic acid, and n-octyl-
A monomer mixture composed of 20.8 g of 3-mercaptopropionate was added dropwise over 1 hour. After dropping,
After performing polymerization by heating and stirring for 2 hours, the mixture was cooled to 27 ° C. to obtain a latex (a dispersion of resin particles composed of a low molecular weight resin). This latex is referred to as “latex (2 L)”.

The resin particles constituting this latex (2 L) have a peak molecular weight of 11,000,
The weight average particle size of the resin particles was 128 nm. [Colored particles 1Bk to 9Bk and comparative colored particles 1Bk,
Production of 2Bk and 4Bk] Anionic surfactant (10
1) 59.0 g was dissolved under stirring in 1600 ml of ion-exchanged water. While stirring this solution, 420.0 g of carbon black “REGAL 330” (manufactured by Cabot Corporation) was gradually added, and then a stirrer “CLEARMIX” (M Technic Co., Ltd.) as shown in FIG. )) To obtain a dispersion of colorant particles (hereinafter, referred to as a dispersion liquid).
It is referred to as "colorant dispersion (Bk)". ) Was prepared. The particle diameter of the colorant particles in this colorant dispersion 1 was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), and as a result, the weight average particle diameter was 90 nm.

420.7 g of latex 1HML (in terms of solid content), 900 g of ion-exchanged water and "colorant dispersion (B
k) "was stirred in a reaction vessel (four-necked flask) equipped with a temperature sensor, a cooling tube, a nitrogen introducing device, and a stirring device. After adjusting the temperature in the container to 30 ° C., a 5N (mol / l) aqueous sodium hydroxide solution was added to the solution to adjust the pH to 8 to 11.0.

Next, magnesium chloride hexahydrate 1
An aqueous solution in which 2.1 g was dissolved in 1,000 ml of ion-exchanged water was added over 10 minutes at 30 ° C. with stirring. After standing for 3 minutes, heating was started, and the temperature of the system was raised to 90 ° C. over 60 minutes. In this state, the particle size of the associated particles was measured with a “Coulter counter TA-II”, and when the number average particle size became 4 to 7 μm, sodium chloride 4
An aqueous solution prepared by dissolving 0.2 g in 1000 ml of ion-exchanged water was added to stop the particle growth, and the fusion was continued by heating and stirring at a liquid temperature of 98 ° C. for 6 hours as an aging treatment.

Further, 96 g of 2 L of latex (resin dispersion of resin particles) was added, and the mixture was heated and stirred for 3 hours to fuse 2 L of latex on the surface of the aggregated particles of latex (1HML). Here, sodium chloride 40.2
g was added, and the mixture was cooled to 30 ° C. at a rate of 8 ° C./min, and the pH was adjusted to 2.0 by adding hydrochloric acid, and stirring was stopped. The resulting salted-out, aggregated and fused particles were filtered, washed repeatedly with ion-exchanged water at 45 ° C, and then dried with warm air at 40 ° C to obtain colored particles.

The colorant dispersion state is controlled by controlling the pH of the aggregating step, the timing of adding 2 L of latex, and the stirring intensity, and the particle size and the variation coefficient of the particle size distribution are arbitrarily adjusted by classification in a liquid. As a result, colored particles 1Bk to 9Bk and colored particles 1Bk, 2Bk, and 4Bk for comparison, which are composed of colored particles having the dispersion state, shape characteristics, and particle size distribution characteristics shown in Tables 1 and 2, were obtained. [Production of colored particles 10Bk and comparative colored particles 3Bk]
Colored particles 1Bk to 9Bk and comparative colored particles 1Bk, 2
In the production of Bk and 4Bk, colored particles 10Bk and comparative colored particles 3Bk were obtained in the same manner except that 2 L of latex was not added. [Coloring particles 1Y to 9Y and comparative coloring particles 1Y, 2Y,
Production of 4Y] 90 g of an anionic surfactant (101) was stirred and dissolved in 1600 ml of ion-exchanged water. While stirring this solution, the dye (CI Solvent Yellow 9) was added.
3) By gradually adding 420 g, and then performing dispersion treatment using the above-described stirrer “CLEARMIX” (manufactured by M Technique Co., Ltd.), a dispersion of colorant particles (hereinafter referred to as “colorant dispersion”). Liquid (Y) "). The particle size of the colorant particles in the colorant dispersion (Y) is
When measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle diameter was 250.
nm.

Production Examples 1Bk to 9Bk and Comparative Colored Particles 1Bk, 2Bk, and 4B, except that 168 g of the colorant dispersion (Y) was used instead of 200 g of the colorant dispersion (Bk).
Colored particles were obtained in the same manner as in Bk. The colored particles thus obtained are referred to as “colored particles 1Y to 9Y” and “comparative colored particles 1Y, 2Y, and 4Y”. [Production of colored particles 10Y and comparative colored particles 3Y] In the production of the colored particles 1Y to 9Y and the comparative colored particles 1Y, 2Y, and 4Y, the colored particles 10Y and the comparative Colored particles for use 3Y were obtained. [Production of Colored Particles 11Y, 12Y, and 13Y] In the production of the colored particles 1Y to 9Y and the comparative colored particles 1Y, 2Y, and 4Y, coloring was performed in the same manner except that the colorant dispersion liquid produced according to the following procedure was used. Particles 11Y and colored particles 12
Y and colored particles 13Y were obtained.

The colorant dispersion for the colored particles 11Y is prepared by dispersing 120 parts by mass of dimethylformamide using a disper, and dispersing the dispersed solvent and C.I. I. Solvent Yellow 93 water wet colorant paste (colorant content 35% by mass) 2
The mixed solution of parts by mass is transferred to a container capable of vacuum degassing, and the pressure is reduced to 100 to 1 while reducing the pressure to 6.65 kPa or less with an aspirator.
After heating to 20 ° C. and distilling off water contained in the system as much as possible, the temperature is controlled at 120 ° C. Next, 2 parts by mass of chlorosulfuric acid was added as a sulfonating agent, and the mixture was reacted with stirring for 5 hours. I. Solvent Yellow 93 was washed several times with an excess of solvent, poured into water, and subjected to surface treatment from the filtrate. I. Solvent Yellow 93 water wet colorant paste (colorant content 31% by mass)
I got Next, 0.90 kg of sodium n-dodecyl sulfate
And 10.0 liters of pure water were added and stirred and dissolved. I. 3.38 kg of a water-wet colorant paste of Solvent Yellow 93 (colorant content: 31% by mass) was gradually added, and the mixture was stirred well for 1 hour, followed by continuous dispersion for 60 minutes using CLEARMIX. Thus, a colorant dispersion for the colored particles 11Y was obtained.

[0302] The colorant dispersion for the colored particles 12Y is composed of 0.90 kg of sodium n-dodecyl sulfate and 1 part of pure water.
0.0 liter was added and dissolved by stirring. Into this solution was added C.I. I. Solvent Yellow 93 water-wet colorant paste (colorant content 73% by mass) was 1.44.
After slowly adding 1 kg and stirring well for 1 hour, FIG.
It was obtained by continuously dispersing for 60 minutes using the clear mix shown in (b).

The colorant dispersion for the colored particles 13Y is composed of 0.90 kg of sodium n-dodecyl sulfate and 1% of pure water.
0.0 liter was added and dissolved by stirring. Into this solution was added C.I. I. Solvent Yellow 93 water-wet colorant paste (colorant content 15% by mass) was 7.00
After slowly adding 1 kg and stirring well for 1 hour, FIG.
Using the clear mix shown in (b), the mixture was continuously dispersed for 60 minutes. [Production Examples 1M to 9M and comparative colored particles 1M, 2M, 4
M] 90 g of an anionic surfactant (101) was stirred and dissolved in 1600 ml of ion-exchanged water. While stirring this solution, the pigment (CI Pigment Red 122) 420
g, and then subjected to a dispersion treatment using the aforementioned stirrer “CLEARMIX” (manufactured by M Technique Co., Ltd.) to obtain a dispersion of colorant particles (hereinafter referred to as “colorant dispersion ( M) "). When the particle size of the colorant particles in this colorant dispersion liquid (M) was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle size was 250 nm. .

Production Examples 1Bk to 9Bk and Comparative Colored Particles 1Bk, 2Bk, 4B except that 166 g of the colorant dispersion (M) was used instead of 200 g of the colorant dispersion (Bk).
Colored particles were obtained in the same manner as in Bk. The colored particles thus obtained are referred to as “colored particles 1M to 9M” and “comparative colored particles 1M, 2M, 4M”. [Production of colored particles 10M and comparative colored particles 3M] In the production of colored particles 1M to 9M and comparative colored particles 1M, 2M, and 4M, the same procedure was repeated except that 2 L of latex was not added. 3M of colored particles for use was obtained. [Production of colored particles 11M, 12M, and 13M] In the production of colored particles 1M to 9M and comparative colored particles 1M, 2M, and 4M, coloring was performed in the same manner except that the colorant dispersion produced according to the following procedure was used. Particles 11M and colored particles 12
M and colored particles 13M were obtained.

The colorant dispersion for the colored particles 11M was prepared by dispersing 140 parts by mass of a quinoline solvent using a disper.
Dispersed solvent and C.I. I. Pigment Red 122 water-wet colorant paste (colorant content: 37% by mass) A mixture of 2 parts by mass was transferred to a container capable of vacuum degassing, and heated to 100 to 120 ° C while reducing the pressure to 6.65 kPa or less with an aspirator. After the water contained in the system is distilled off as much as possible, the temperature is controlled at 120 ° C. Then, 2 parts by mass of chlorosulfuric acid was added as a sulfonating agent, and the mixture was reacted with stirring for 3 hours. I. Pigment Red 122 was washed several times with an excess solvent, then poured into water, and C.I. I. A water-wet colorant paste of Pigment Red 122 (colorant content: 31% by mass) was obtained.
Next, 0.90 kg of sodium n-dodecyl sulfate and 10.0 liters of pure water were added and dissolved by stirring. In this solution,
C. I. 3.87 kg of a water-wet colorant paste of Pigment Red 122 (colorant content: 31% by mass) is gradually added, and the mixture is stirred well for 1 hour, and then continuously dispersed for 60 minutes using the clear mix shown in FIG. 3 (b). Thus, a colorant dispersion for the colored particles 11M was obtained.

The colorant dispersion for the colored particles 12M was prepared by dissolving 0.90 kg of sodium n-dodecyl sulfate and 1% pure water.
0.0 liter was stirred and dissolved, and C.I. I. 1.64 k of a water-wet colorant paste of Pigment Red 122 (colorant content: 73% by mass)
g was gradually added and, after stirring well for 1 hour, FIG.
The dispersion was continuously dispersed for 60 minutes using the clear mix shown in (1) to obtain a colorant dispersion liquid for colored particles 12M.

The colorant dispersion for the colored particles 13M was prepared by dissolving 0.90 kg of sodium n-dodecyl sulfate and 1% pure water.
0.0 liter was added and dissolved by stirring. Into this solution was added C.I. I. Pigment Red 122 in a water-wet colorant paste (colorant content: 15% by mass) is 8.00.
After slowly adding 1 kg and stirring well for 1 hour, FIG.
Using the clear mix shown in (b), the mixture was continuously dispersed for 45 minutes to obtain a colorant dispersion for the colored particles 13M. [Production Examples 1C to 9C and Comparative Colored Particles 1C, 2C, 4
C] 90 g of an anionic surfactant (101) was stirred and dissolved in 1600 ml of ion-exchanged water. While stirring this solution, a pigment (CI Pigment Blue 15: 3) 40
0 g was gradually added, and then subjected to a dispersion treatment using “CLEARMIX” (manufactured by M Technique Co., Ltd.), whereby a dispersion of colorant particles (hereinafter referred to as “colorant dispersion (C)”) was obtained. .) Was prepared. When the particle size of the colorant particles in the colorant dispersion liquid (C) was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the weight average particle size was 250 nm. .

Production Examples 1Bk to 9Bk and comparative colored particles 1Bk, 2Bk, except that 98.7 g of the colorant dispersion (C) was used instead of 200 g of the colorant dispersion (Bk).
Colored particles were obtained in the same manner as in 4Bk. The colored particles thus obtained are referred to as “colored particles 1C to 9C and comparative colored particles 1C, 2C, and 4C”. [Production of colored particles 10C and comparative colored particles 3C] In the production of the colored particles 1C to 9C and the comparative colored particles 1C, 2C, and 4C, except that 2 L of the latex was not added, the colored particles 10C and the comparative colored particles 10C were compared. Thus, colored particles 3C were obtained. [Production of colored particles 11C, 12C, and 13C] In the production of colored particles 1C to 9C and comparative colored particles 1C, 2C, and 4C, coloring was performed in the same manner except that the colorant dispersion liquid produced by the following procedure was used. Particles 11C and colored particles 12
C and colored particles 13C were obtained.

The colorant dispersion for the colored particles 11C was prepared by dispersing 120 parts by mass of dimethylacetamide using a disper, and dispersing the dispersed solvent and C.I. I. Pigment Blue 1
5: 3 water-wet colorant paste (colorant content 35% by mass)
2 parts by mass of the mixed solution is transferred to a container capable of vacuum degassing, and the pressure is reduced to 100 to 65 kPa by an aspirator.
After heating to 120 ° C. and distilling out the water contained in the system as much as possible, the temperature is controlled to 120 ° C. Next, 2 parts by mass of a sulfonated pyridine complex was added as a sulfonating agent, and the mixture was reacted with stirring for 3 hours. I. Pigment Blue 15: 3 was washed several times with an excess of solvent, then poured into water, and subjected to surface treatment from the filtrate. I.
Pigment Blue 15: 3 water-wet colorant paste (colorant content: 31% by mass) was obtained. Next, 0.90 kg of sodium n-dodecyl sulfate and 10.0 liters of pure water were added and dissolved by stirring. I. Pigment Blue 15:
1.94 kg of a water-wet colorant paste (colorant content: 31% by mass) of No. 3 was gradually added, and the mixture was stirred well for 1 hour.
Continuous dispersion was performed for 60 minutes using the CLEAR MIX shown in FIG. 3B, and a colorant dispersion for the colored particles 11C was obtained in this manner.

[0310] The colorant dispersion for the colored particles 12C was 0.90 kg of sodium n-dodecyl sulfate and 1% of pure water.
0.0 liter was added and dissolved by stirring. To this solution was added C.I. I. Pigment Blue 15: 3 water-wet colorant paste (colorant content 73% by mass)
After slowly adding 1 kg and stirring well for 1 hour, FIG.
Using the clear mix shown in (b), the mixture was continuously dispersed for 60 minutes to obtain a colorant dispersion for the colored particles 12C.

The coloring dispersion for the coloring particles 13C is as follows:
9. 0.90 kg of sodium n-dodecyl sulfate and pure water
0 liter was added and dissolved by stirring. To this solution was added C.I. I. Pigment Blue 15: 3 water-wet colorant paste (colorant content: 15% by mass) 4.00 kg
Was gradually added, and the mixture was stirred well for 1 hour, and then continuously dispersed for 45 minutes using the clear mix shown in FIG.
Thus, a colorant dispersion liquid for the colored particles 13C was obtained.

Tables 1 to 4 show the results such as the number particle size and the coefficient of variation of the number distribution of the colored particles obtained as described above.

[0313]

[Table 1]

[0314]

[Table 2]

[0315]

[Table 3]

[0316]

[Table 4]

Tables 5 to 8 show the results regarding the dispersion state of the colorant.

[0318]

[Table 5]

[0319]

[Table 6]

[0320]

[Table 7]

[0321]

[Table 8]

Production of Toner The above black colored particles 1Bk to 1
10Bk, comparative black colored particles 1Bk-4Bk, yellow colored particles 1Y-13Y, comparative yellow colored particles 1Y
~ 4Y, magenta colored particles 1M ~ 13M, comparative magenta colored particles 1M ~ 4M, cyan colored particles 1C ~ 13C,
Hydrophobic silica (number average primary particle diameter = 10 nm, degree of hydrophobicity = 63) was added to each of the comparative cyan colored particles 1C to 4C at a ratio of 1.0% by mass, and hydrophobic titanium oxide (number Average primary particle size = 25 nm, degree of hydrophobicity = 6
0) was added at a ratio of 1.2% by mass, and the mixture was mixed with a Henschel mixer to obtain a toner.

The shape and particle size of these colored particles are not changed by the addition of hydrophobic silica and hydrophobic titanium oxide. The toners obtained from the above colorants are referred to as toners 1Bk to 10Bk and comparative toner 1Bk.
~ 4Bk, toner 1Y ~ 13Y, comparative toner 1Y ~ 4
Y, toners 1M to 13M, comparative toners 1M to 4M, toners 1C to 13C, and comparative toners 1C to 4C. Manufacture of carrier Manufacture of ferrite core material 18 mol% of MnO, 4 mol% of MgO, Fe ₂ O ₃
Was pulverized, mixed and dried in a wet ball mill for 2 hours, calcined by holding at 900 ° C. for 2 hours, and pulverized in a ball mill for 3 hours to form a slurry. A dispersant and a binder were added, and the mixture was granulated and dried by a spray drier, and then subjected to main firing at 1200 ° C. for 3 hours to obtain ferrite core material particles having a specific resistance of 4.3 × 10 Ω · cm. Production of Coating Resin First, cyclohexyl methacrylate / methyl methacrylate (methyl methacrylate) was prepared by an emulsion polymerization method using sodium benzenesulfonate having an alkyl group having 12 carbon atoms as a surfactant and a concentration in an aqueous medium of 0.3% by mass. A copolymer having a copolymerization ratio of 5/5) was synthesized, and the volume average primary particle size was 0.1 μm, the weight average molecular weight (Mw) was 200,000,
Number average molecular weight (Mn) 91,000, Mw / Mn = 2.
2. Fine resin particles having a softening point (Tsp) of 230 ° C and a glass transition temperature (Tg) of 110 ° C were obtained. The resin fine particles azeotroped with water in an emulsified state, and the residual monomer content was 510 ppm.

Next, 100 parts by mass of the ferrite core material particles and 2 parts by mass of the resin fine particles were put into a high-speed stirring mixer equipped with stirring blades, and stirred and mixed at 120 ° C. for 30 minutes to use the action of mechanical impact force. Thus, a resin-coated carrier having a volume average particle size of 39 μm was obtained. Manufacture of Developer Each of the toners comprising colored particles to which an external additive was added was mixed with a carrier to prepare a developer having a toner concentration of 6% by mass. The obtained developer is developer 1
Bk-10Bk, comparative developer 1Bk-4Bk, developer 1Y-13Y, comparative developer 1Y-4Y, developer 1M-
13M, comparative developers 1M to 4M, and developers 1C to 1
3C and comparative developers 1C to 4C. <Examples 1 to 13 and Comparative Examples 1 to 4> The respective color developers of black, yellow, magenta, and cyan are combined to form Examples 1 to 13 and Comparative Examples 1 to 4, respectively. However, the developer 11Y, 11M, 11C, the developer 12Y,
1Bk was used as the black developer to be combined with 12M, 12C and the developers 13Y, 13M, 13C.

Examples 1 to 1 comprising combinations of the above-mentioned developers
3. Each sample of Comparative Examples 1 to 4 was put into a modified machine of a digital color copying machine “7823” (manufactured by Konica Corporation) of an intermediate transfer system, and was subjected to a high temperature and high humidity environment (temperature of 33 ° C., relative humidity of 80).
%), The following items were evaluated. A laminated organic photoreceptor was used as the photoreceptor.

First, a full-color image (Y /
(M / C / Bk, each having a pixel rate of 15%), the following evaluation was performed after 5,000 continuous images were formed, and the same evaluation was performed after further standing for 72 hours. The evaluation items performed are as follows.

The evaluation was performed for the density of 10% halftone dot, line width, crushed characters, fine dot dust, color difference, and fog. Each evaluation item was measured by the following method. The evaluation of the secondary color of the color toner, that is, the evaluation of a multicolor image formed by the image forming apparatus was performed by forming an image using a combination of toners. Specifically, a monochromatic image of red was formed with yellow and magenta toners, a green image was formed with yellow and cyan toners, and a blue image was formed with cyan and magenta toners. The fog was evaluated by forming a total of 100,000 images as described below. (1) 10% dot density: Macbeth reflection densitometer “RD-918” for 10% dot image area of 20 mm × 20 mm
, The relative image density with respect to the white background was measured. 10
The evaluation of the% halftone dot density was performed in order to evaluate the reproducibility of dots and the reproducibility of halftones. If the density change is within 0.10, the image quality change is small and it can be said that there is no problem. (2) Line width: The line width of a line image corresponding to an image signal of a two-dot line is determined by a print evaluation system “RT200
0 "(manufactured by Yarman Corporation). If both the line width of the first formed image and the line width of the 20,000th formed image are 200 μm or less and the change in the line width is less than 10 μm, it can be said that fine line reproducibility is not a problem. (3) Character collapse: A character image of 3 points and 5 points was formed and evaluated according to the following criteria.

"◎": Three points and five points are clear and easily legible. "O": At 3 points, some unreadable characters occurred.

The 5 points are clear and easily legible. “×”: At 3 points, most characters are unreadable.

(5) Fine dot dust: A 10% halftone dot image is formed on the entire secondary color (red, blue, green) image, and dots are formed with a loupe. The surrounding Chile was observed. An item with almost no detectable dust was marked with “◎”, slight dust was noted, but it was marked as “○” if it was not noticed unless watched closely, and “×” was marked as easily detectable with dust. (5) Color difference: The color of the solid image portion of the secondary colors (red, blue, green) in each of the first formed image and the 20,000th formed image is referred to as "Macbeth Co."
lor-Eye7000 ", and CMC (2:
1) The color difference was calculated using the color difference equation. Among the above secondary colors, those having the largest color difference were selected, and those having a color difference determined by the CMC (2: 1) color difference formula of 5 or less were within the allowable range. A sample having a color difference of 3 or less was rated as “◎”, a sample with a color difference greater than 3 and 5 or less was rated “○”, and a sample with a color difference greater than 5 was rated “x”. (6) Transparency of OHP Image Regarding the transparency of the OHP image, a transmission image (OHP image) was prepared and evaluated by the following method. The toner adhesion amount was evaluated in the range of 0.7 ± 0.05 (mg / cm ² ). For the fixed image, see “3.
The visible spectral transmittance of the image was measured with a “30 type self-recording spectrophotometer” using an OHP sheet not carrying a toner as a reference.
Difference in spectral transmittance in nm, 650 n for magenta toner
The difference between the spectral transmittance at m and 550 nm and the difference between the spectral transmittance at 500 nm and 600 nm for the cyan toner were determined.
It was a measure of the transparency of the HP image. When this value is 70% or more, it can be determined that the film has good transmittance. The transparency was also evaluated by selecting one having the largest difference in spectral transmittance from the above yellow, magenta, and cyan.

◎: 90% or more ○: 70 to 90% ×: less than 70% (7) Fog occurrence: under high temperature and high humidity environment (temperature 33)
° C, relative humidity 80%), the full-color image (Y /
(M / C / Bk pixel rate is 15%)
After printing 000 sheets, the mode in which the power is turned off and the printer is paused for 2 hours is repeatedly performed 100 times (total 100,000 sheets), and the formed images are sequentially observed. The number was measured.

The results are shown in Table 9 below.

[0333]

[Table 9]

As is clear from the results of the above examples, the use of the toners of Examples 1 to 13 according to the present invention enables continuous use in a high-temperature and high-humidity environment and even after standing for 72 hours. It was confirmed that an image having no change in halftone density was obtained, and even in a multicolor image and under the above-mentioned environment, a multicolor image having a good color difference was always obtained without being affected by the colorant contained in each color developer. Color image obtained,
Furthermore, it was confirmed that a high quality image excellent in developability and fine line reproducibility was stably formed for a long period of time. On the other hand, when the comparative sample was used under the same conditions, the result as achieved in the example was not obtained.

[0335]

As is clear from the results of the above embodiment,
By specifying the dispersion state and occupation state of the island portion of the colorant component in the toner of the present invention, i.e., the toner particles having a sea-island structure, regardless of the influence of the residue on the surface of the toner particles, It has been found that it is possible to prevent the change in the amount of charge under moisture and to prevent the occurrence of density unevenness in a halftone image of an image formed after being stopped for a long period of time.

Further, it has been found that a multicolor image having excellent transparency and good color difference can be obtained by the toner of the present invention, and high image quality excellent in developability and fine line reproducibility can be obtained. It has been found that it is possible to stably form an image over a long period of time, and to achieve a toner which can be applied particularly to a digital multicolor image forming method.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating toner particles having a sea-island structure according to the present invention.

FIG. 2 is a schematic diagram in which toner particles having a sea-island structure according to the present invention are divided by Voronoi polygons.

FIG. 3 is a stirring device used for obtaining colorant particles contained in toner particles having a sea-island structure according to the present invention.

FIG. 4 is a schematic configuration diagram showing an example of an image forming apparatus using a transfer roll applied to the present invention.

FIG. 5 is a schematic configuration diagram showing an example of an image forming apparatus using a transfer belt applied to the present invention.

FIG. 6 is an explanatory configuration diagram showing an example of a configuration of a fixing device applied to the present invention.

FIG. 7 is a perspective configuration diagram of a toner recycling member.

FIG. 8 is a schematic diagram illustrating toner having no corners or toner having corners.

[Explanation of symbols]

 101 Screen 102 Rotor M Stirring Chamber 103 Pressurized Vacuum Attachment 104 Preliminary Dispersion Liquid Inlet 105 Dispersion Liquid Outlet 106 Temperature Sensor 107 Cooling Jacket 108 Cooling Coil 111 Dispersion Container 112 Stirring Device 113 Stirring Shaft 10 Photoconductor 11 Charger 12 Digital Image Exposure Light DESCRIPTION OF SYMBOLS 13 Developing device 14 Separator 15 Transfer roll 16 Bias power supply 17 Cleaning blade 18 Static elimination lamp 19 Feeding roller 20 Fixing device P Transfer material Pa, pb, Pc, Pd Image forming unit 1a, 1b, 1c, 1d Photoconductor 2a, 2b 2c, 2d Latent image forming unit 3a, 3b, 3c, 3d Developing unit 4a, 4b, 4c, 4d Transfer discharge unit 5a, 5b, 5c, 5d Cleaning unit 6a, 6b, 6c, 6d Charger 22a, 22b, 22c , 22d separation discharge Reference Signs List 23 Fixing device 24 Cleaning device 25 Discharge port 84 Heating body 85 Alumina substrate 86 Resistive material 87 Temperature detecting element 88 Film 89 Drive roller 90 Follower roller 91 Feeding shaft 92 Winding shaft 93 Unfixed toner image 94 Transfer material 95 Press roller 75 Heating Element

Continued on front page (72) Inventor Yoshiki Nishimori 2970, Ishikawacho, Hachioji-shi, Tokyo Konica Corporation (72) Inventor Hiroyuki Yamada 2970, Ishikawacho, Hachioji-shi, Tokyo Konica Corporation (72) Inventor Hiroshi Yamazaki Tokyo 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H005 AA01 AA11 AA15 AB02 AB03 CA03 EA05 EA10 2H033 AA01 AA09 BA30 BA42 BA43 BA52 BA58 BB05 BB29 BB33 BB37 BE03

Claims (22)

[Claims] 1. An electrostatic image developing toner having toner particles containing at least a resin and a colorant, wherein the toner particles have a sea-island structure, and are provided between the centers of gravity of adjacent islands in the sea-island structure. Average area of the Voronoi polygon formed by the perpendicular bisector of
A toner for developing electrostatic images, wherein the toner has a molecular weight of 120,000 nm ² and a variation coefficient of the area of the Voronoi polygon is 25% or less. 2. A toner for developing an electrostatic charge image having toner particles containing at least a resin and a colorant, wherein the toner particles have a sea-island structure, and are located between the centers of gravity of adjacent islands in the sea-island structure. Of the Voronoi polygon formed by the perpendicular bisector of
A toner for developing an electrostatic image, wherein the toner has a 000 nm ² and a variation coefficient of the area of the Voronoi polygon is 20% or less. 3. An electrostatic image developing toner having toner particles containing at least a resin and a colorant, wherein the toner particles have a sea-island structure, and are provided between the centers of gravity of adjacent islands in the sea-island structure. Average area of the Voronoi polygon formed by the perpendicular bisector of
120,000 nm ² and 160,000 nm ²
The toner for developing an electrostatic image, wherein the number of islands forming the Voronoi polygon having the above area is 3 to 20% by number of the entire islands. 4. A toner for developing an electrostatic charge image having toner particles containing at least a resin and a colorant, wherein the toner particles have a sea-island structure, and have a radius of 1000 nm centered on the center of gravity in the cross section of the toner particles. The average value of the area of the Voronoi polygon formed by the vertical bisectors between the centers of gravity of the islands outside the circle is formed by the vertical bisectors between the centers of gravity of the islands inside the circle. A toner for developing an electrostatic image, wherein the toner is smaller than the average value of the area of the Voronoi polygon. 5. An electrostatic image developing toner having toner particles containing at least a resin and a colorant, wherein the toner particles have a sea-island structure, and the center of gravity of adjacent islands in the sea-island structure. Among the Voronoi polygons formed by the perpendicular bisectors between them, the islands that are in contact with the outer periphery of the toner and form the Voronoi polygons having an area of 160,000 nm ² or more are formed on the entire island. 3 to 20% by number of the toner for developing an electrostatic image. 6. An electrostatic image developing toner having toner particles containing at least a resin and a colorant, wherein the toner particles have a sea-island structure, and have a length along the outer periphery of the cross section of the toner particles. A toner for developing an electrostatic image, comprising a region having an island portion of 500 to 6000 nm and a depth of 100 to 200 nm. 7. An electrostatic image developing toner having toner particles containing at least a resin and a colorant, wherein the toner particles have a sea-island structure, and the islands are composed of islands having different luminances. 2. The method according to claim 1, wherein
7. The toner for developing an electrostatic charge image according to any one of items 6 to 6. 8. An electrostatic image developing toner having toner particles containing at least a resin and a colorant, wherein the toner particles have a sea-island structure, and the resin constitutes a sea portion, and the colorant The toner for developing an electrostatic image according to any one of claims 1 to 7, wherein? 9. A toner for developing electrostatic images having toner particles containing at least a resin and a colorant, wherein the colorant is a water-wet colorant paste. The toner for developing an electrostatic image according to any one of the above items. 10. The toner according to claim 1, wherein the toner has a number variation coefficient in a number particle size distribution of 27% or less and a shape coefficient variation coefficient of 16% or less. The toner for developing an electrostatic image according to the above. 11. The toner according to claim 1, wherein a ratio of toner particles having no corners is 50% by number or more, and a number variation coefficient in a number particle size distribution is 27% or less.
10. The electrostatic image developing toner according to any one of items 9 to 9. 12. The toner has a shape factor of 1.2 to 1.
6. The ratio of the toner particles in the range of 6 to 65% by number or more, the variation coefficient of the shape factor is 16% or less, and the number variation coefficient in the number particle size distribution is 27% or less. 10. The electrostatic image developing toner according to any one of 1 to 9. 13. The toner has a number average particle size of 3 to 9 μm.
The toner according to claim 1, wherein m is m. 14. The toner according to claim 1, wherein the particle diameter of the toner particles is D.
(Μm), the natural logarithm lnD is plotted on the horizontal axis,
The relative frequency (m1) of the toner particles included in the most frequent class in the histogram showing the number-based particle size distribution in which the horizontal axis is divided into a plurality of classes at intervals of 0.23, and the next highest frequency after the most frequent class The electrostatic image developing toner according to any one of claims 1 to 13, wherein the sum (M) of the relative frequency (m2) of the toner particles included in the class is 70% or more. 15. The electrostatic image developing toner according to claim 1, comprising at least a resin and a colorant, wherein at least a polymerizable monomer is polymerized in an aqueous medium. And a toner for developing an electrostatic image. 16. The electrostatic image developing toner according to claim 1, comprising at least a resin and a colorant, wherein at least the resin particles are aggregated and fused in an aqueous medium. And a toner for developing an electrostatic image. 17. The electrostatic image developing toner according to claim 1, comprising at least a resin and a colorant, wherein the toner is obtained by polymerizing at least a polymerizable monomer. A toner for developing an electrostatic image, which is obtained by salting out / fusing resin particles and colorant particles formed through the steps. 18. The electrostatic image developing toner according to claim 1, which contains at least a resin and a colorant, wherein the toner comprises resin particles obtained by a multi-stage polymerization method. A toner for developing an electrostatic image, which is obtained by salting out / fusing colorant particles. 19. The electrostatic image developing toner according to claim 1, which contains at least a resin and a coloring agent, wherein the toner is provided on the surface of the resin particles and the coloring particles. A toner for developing electrostatic images, which is obtained by forming a resin layer formed by fusing resin particles by a salting-out / fusion method. 20. A method for producing a toner for developing an electrostatic image, comprising at least a resin and a colorant, the method comprising:
20. A method for producing a toner for developing an electrostatic image, characterized by producing the toner according to any one of the above items. 21. An image forming method comprising the steps of: converting an electrostatic latent image formed on a photoreceptor into a visible image; transferring the visible image onto a recording medium; and fixing by heating. An image forming method which is performed by a fixing device having a film, and wherein the visible image is formed by using the toner for developing an electrostatic image according to any one of claims 1 to 14. 22. The image forming method according to claim 21, further comprising a step of converting the electrostatic latent image formed on the photoconductor into a visible image, transferring the visible image onto a recording medium, and fixing by heating. An image forming method, wherein the irradiation on the photoreceptor is performed by digital exposure.