JP2007213029A - Toner and developer using the toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a toner having a small particle diameter and excellent in fluidity and durability. <P>SOLUTION: The toner includes at least a binder resin and a release agent, wherein the following relationships are satisfied: 2 μm≤D4≤4 μm (a), 0.05 μm≤Dw≤0.3 μm (b), Dw≤0.075×D4 (c), F≤-40×Dw+19 (d), and F≤20×Dw+5 (e), wherein D4 is a weight-average particle diameter of the toner, Dw is an average dispersion diameter of wax as the release agent in the toner and F is a pulverizability index of the toner. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a toner used for image formation in an electrostatic copying process such as a copying machine, a facsimile machine, and a printer, and a developer using the toner.

In the developing process, the developer used in electrophotography, electrostatic recording, electrostatic printing, etc. is once attached to an image carrier such as a photoreceptor on which an electrostatic charge image is formed, and then transferred to a transfer process. After being transferred from the photoconductor to a transfer medium such as transfer paper, the toner is fixed on the paper surface in a fixing step.
As a method for visualizing an electric latent image using toner, a magnetic brush method, a cascade development method, a powder cloud method, and the like are known.
In general, an electrostatic latent image is developed with toner on a photosensitive member, and then transferred to a transfer sheet or the like and fixed to obtain an image. As a fixing method at this time, a hot roll fixing method in which pressure heating is performed with a heated roll is generally used. In this hot roll fixing method, heat efficiency is high and fixing can be performed quickly, but a so-called offset phenomenon in which a part of the toner image adheres to the roll surface and moves onto the sheet again easily occurs.

Conventionally, in order to prevent offset, the surface of the fixing roller is formed of a material excellent in releasability with respect to toner (silicon rubber, fluorine resin, etc.), and further, the surface is formed to prevent offset and fatigue on the roller surface. Covering with a thin film of liquid having high releasability, such as silicon oil and fluorine oil.
However, this method is extremely effective in preventing toner offset, but it requires a device for supplying an offset prevention liquid, which causes problems such as a complicated configuration of the entire fixing device. Further, this oil application also causes delamination between layers constituting the fixing roller, resulting in an adverse effect of promoting the shortening of the life of the fixing roller.
Therefore, instead of using an oil supply device, from the idea of supplying an offset prevention solution from the toner particles at the time of heat and pressure fixing, as described in Patent Documents 1, 2, etc., A method of adding a release agent such as molecular weight polyethylene or low molecular weight polypropylene has been proposed.

Conventionally, a commonly used toner manufacturing method is to uniformly mix toner constituent materials such as a binder resin and a colorant in a powder form, and then melt and knead the toner constituent materials and further pulverize them. Then, there is a melt-kneading pulverization method in which the toner is obtained by classification.
In recent years, from the viewpoint of high image quality, there has been an increasing demand for reducing the particle size of these toners.
In this melt-kneading pulverization method, for example, when trying to reduce the particle size of the toner by a method of pulverizing using an airflow pulverizer, there is a problem that the specific surface area of the toner increases and the fluidity of the toner decreases. Occurred.

Further, as a method for producing a toner, there is a method for producing a toner by a polymerization method in addition to a method for producing a toner by a melt kneading and pulverizing method.
Since the toner obtained by the polymerization method has a small particle size, it is easy to obtain a high-definition image, and because it is spherical, the specific surface area of the toner is kept small and the fluidity is constant. Can keep the level. Furthermore, there can be obtained an advantage that transferability to a transfer medium is excellent.
However, in the polymerization method, for example, because non-standard products such as fine powder generated in the manufacturing process cannot be recycled, the manufacturing cost is high, and most of the toner particles are spherical. In this cleaning process, there is a problem that the toner particles are easily rubbed through a cleaning member such as a cleaning blade, and defective cleaning is likely to occur.
For this reason, along with the polymerization method, the melt-kneading pulverization method in which the toner constituent material is melted and kneaded and then pulverized to obtain the toner is still used as the mainstream method.

For example, in Patent Document 3, as a method for reducing the particle diameter of a toner produced by a melt-kneading pulverization method, at least a binder resin and a colorant are contained, and the toner is produced by a pulverization method. It is 0 to 8.5 μm, and the circularity indicated by circularity = π · (diameter of a circle equal to the area of the particle image) / perimeter of the particle image is 0.955 to 0.980. A featured toner and a method for producing the toner are disclosed.
That is, Patent Document 3 discloses an electrophotographic toner having a small particle size, high circularity, and excellent image characteristics and transfer characteristics by a toner manufacturing method including at least a step of pulverizing with an impact pulverizer. A method of obtaining is disclosed.

However, for example, when the toner particles constituted by including a release agent in the toner composition are reduced in size by the method disclosed in Patent Document 3, the release agent contained in the toner particles is: There is a problem that the ratio of exposure to the toner particle surface increases.
When the amount of the release agent exposed on the toner particle surface increases, the release agent is detached and adheres to the carrier or other charging member, resulting in a spent phenomenon in which the charging ability is lowered. Is known to decrease. Further, it is known that the presence of these release agents deteriorates the fluidity of the toner and the transferability to paper.
For this reason, when the toner particle size is reduced, it is desired to simultaneously reduce the wax dispersion diameter in the toner particles.

For example, Patent Document 4 specifies that the dispersion diameter of the low molecular weight wax in the binder resin is 1 μm or less. This invention aims to suppress the offset phenomenon by defining the dispersion diameter of the release agent, and a method of kneading for a long time with a large shearing force in order to obtain a desired dispersion diameter has been proposed. Yes.
However, since the invention described in Patent Document 4 requires a large shearing force, the production equipment that can be used is limited, and the kneading time becomes very long, which is very disadvantageous in productivity.

In Patent Document 5, the colorant dispersion diameter in the binder resin is 1 μm or less, the release agent dispersion diameter is 0.1 μm or more and 2 μm or less, and the toner concentration is 5% under normal temperature and humidity. When the charge amount obtained when stirring and mixing with the carrier for 10 minutes under the same condition is Q ₂₀ with respect to the charge amount Q ₆₀₀ obtained when stirring and mixing with the carrier for 10 minutes, Z (%) = (Q ₂₀ / Q ₆₀₀ ) A full-color electrophotographic toner having a charge rising ratio calculated by x100 of 70 (%) or more is disclosed.
That is, in Patent Document 5, a mixture composed only of a binder resin, a colorant, and a release agent is melt-kneaded in advance, so that the release agent is more uniformly dispersed in the binder resin in accordance with the dispersion of the colorant. In other words, it is possible to dramatically improve the dispersion of the colorant and the release agent in the binder resin.

JP-A-60-230663 JP-A-1-234858 JP 2005-215148 A JP-A-3-168649 JP-A-11-190914

However, in the inventions described in Patent Documents 4 and 5, the average particle diameter of the toner is not reduced, and at the same time, the average dispersion diameter of the release agent is not reduced. If the dispersion state of the release agent is not uniform, the ratio of the release agent exposed on the surface of the toner particles is increased, the toner fluidity is lowered, and the durability is also deteriorated.
The present invention has been made in view of the above problems, and an object of the present invention is to obtain a toner having a small particle size and excellent fluidity and durability.

The features of the present invention, which is a means for solving the above problems, are listed below.
The toner of the present invention is a toner containing at least a binder resin and a release agent, and the toner has a weight average particle diameter D4 of the toner and an average dispersed particle diameter Dw of the wax in the toner (a). 2 ≦ D4 ≦ 4 (μm), (b) 0.05 ≦ Dw ≦ 0.3 (μm), (c) Dw ≦ 19 × D4, and the toner has a pulverization index F; The average dispersed particle size Dw of the wax satisfies the relationship of the following formulas (1) and (2).
F ≦ −40 × Dw + 19 (1) F ≦ 20 × Dw + 5 (2)
In the toner, the release agent has a viscosity Gw at 100 ° C. of 3 to 10 (mm ² / s), and the binder resin has a viscosity Gr (Pa · s) at 130 ° C. of the release agent. The viscosity Gw (mm ² / s) at 100 ° C. of the agent preferably satisfies the relationship of the following formula (3).
(Gr / 1000) -5 ≦ Gw ≦ (Gr / 1000) +2 (3)
In the toner, the release agent has a main peak at a molecular weight of 1000 to 2500, and the ratio of the weight average molecular weight Mw to the number average molecular weight Mn (Mw / Mn) is 1.3 to 1.8. It is preferable.
In the toner, the release agent is preferably carnauba wax.
In the toner, the amount of the release agent added is preferably 1 to 8 parts by weight with respect to 100 parts by weight of the binder resin.
The toner is preferably obtained by kneading and then pulverizing a toner composition containing at least the binder resin, the wax, and the colorant.
The toner preferably has a fine particle content of 1.0 μm or less of 10% by number or less.
The toner has a weight average particle diameter of 2.0 to 4.0 μm and a ratio (D4 / Dn) of the weight average particle diameter (D4) to the number average particle diameter (Dn) of 1.00 to 1.n. It is preferable to be in the range of 40.

The developer of the present invention is a developer for developing an electrostatic latent image formed on a latent image carrier, and is preferably a one-component developer using the toner.
The developer of the present invention is a developer for developing an electrostatic latent image formed on a latent image carrier, and is preferably a two-component developer comprising a magnetic carrier and the toner.

  According to the present invention, it is possible to provide a toner and a developer that are excellent in hot offset resistance, have a small particle size, and are excellent in fluidity and durability.

The present invention is described in detail below.
The toner according to the present invention is obtained by melt-kneading a toner constituent material containing at least a binder resin and a release agent, and then pulverizing.
Conventionally, in a toner obtained by melt-kneading a toner composition containing a binder resin and a release agent and then pulverizing, the average dispersion diameter of the release agent has not been sufficiently reduced. As the average particle size is decreased, the ratio of the release agent exposed to the particle surface increases, the fluidity of the toner decreases, and the release agent released from the toner particles is further removed on the carrier or image carrier. The carrier spent phenomenon that adheres to the surface occurred.
The present inventor has confirmed that the base toner obtained by melt-kneading the toner constituent materials has a pulverizability index F and an average dispersion particle diameter Dw of the release agent satisfying a certain relationship. The toner can be uniformly and finely pulverized in the resin portion, the average particle diameter and the average dispersion diameter of the release agent are in a desired range, and the ratio of the release agent exposed on the particle surface It has been found that a toner with an extremely small amount can be obtained.
As a result, it is possible to obtain a toner having excellent fluidity, maintaining stable chargeability, and excellent durability.

  The pulverization index F of the toner is an index indicating the hardness of the binder resin that is the main component of the toner. The larger the index, the harder the toner particles are, and the more difficult the pulverization is. A smaller value indicates that the toner particles are fragile and easier to grind.

The pulverizability index of the toner can be measured by the following method.
200 kg of resin is kneaded for 15 minutes with a small two roll (Nishimura Co., Ltd.) heated to 110 ° C., then put into Hosokawa Micron Rotoplex, sifted through coarsely pulverized resin particles for 5 minutes, and passed through 16 mesh Thus, a resin powder that does not pass through 20 mesh is obtained.
10.00 g of this classified resin powder is precisely weighed, pulverized with a mill and mixer MM-I type (manufactured by Hitachi Living Supply Co., Ltd.) for 30 seconds, passed through a 30 mesh sieve, and the weight of the resin not passing (R ) G is precisely weighed, and the residual ratio is obtained from the value of R according to the following formula (I), and this operation is performed three times and the average is obtained as the grindability index.

(Equation 1)
Millability index F = ((R) g / resin weight before grinding (10.00 g)) × 100
・ ・ ・ ・ (I)

Further, the pulverization state of the toner varies depending on the pulverization index F of the toner derived from the characteristics of the binder resin itself and the average dispersion diameter Dw of the release agent dispersed in the binder resin.
FIG. 1 is a diagram showing the relationship between the pulverizability index F of the toner according to the present invention and the average dispersion diameter Dw of the release agent.
In the graph of FIG. 1, a region (A) represents a region of the following formula (1), and a region (B) represents a region of the following formula (2).
The toner according to the present invention satisfies both the following expressions (1) and (2). In FIG. 1, an area indicated by A is an area filled with the toner of the present invention.
By satisfying the relationship of the expression (1), the base toner is kept in a state of being uniformly pulverized in the binder resin region. Furthermore, by satisfying the relationship of the following formula (2), the base toner can be finely pulverized to obtain a toner having a small particle diameter.

(Equation 2)
F ≦ −40 × Dw + 19 (1)

(Equation 3)
F ≦ 20 × Dw + 5 (2)

Since the release agent has a low hardness and is fragile compared to the binder resin, as the average dispersion diameter Dw of the release agent in the base toner increases, the inside of the release agent and the release agent The rate at which crushing occurs at the interface with the binder resin increases. For this reason, as the average dispersion diameter Dw increases, it becomes more difficult for the base toner to be uniformly pulverized in the binder resin region.
In the graph shown in FIG. 1, the range indicated by (A) indicates the range in which the base toner is ensured to be uniformly crushed in the binder resin portion.
In the range indicated by (a), as the average dispersion diameter Dw of the release agent increases, the upper limit of the pulverizability index F of the toner is reduced, and the pulverizability of the binder resin portion in the toner particles is improved. is doing.
By pulverizing the base toner in which the toner pulverization index F and the average dispersion diameter Dw of the release agent are in the range (A) represented by the above formula (1), the toner is exposed to the particle surface. A toner having a small amount of release agent and a good dispersion state can be obtained.

By the way, since the release agent dispersed in the base toner also has a function as a pulverization core, the larger the average dispersion diameter Dw, the better the pulverization of the toner, and the smaller the toner obtained after pulverization. The particle size can be set.
For this reason, when the dispersion state of the release agent is extremely good and the value of the average dispersion diameter is small, in the toner particles, the binder resin and the release agent are close to being in a compatible state, and energy required for pulverization is obtained. Becomes larger. As a result, the pulverizability of the toner composition is impaired, making it difficult to reduce the particle size of the toner.
By crushing the toner in which the pulverization index F of the toner and the average dispersion diameter Dw of the release agent satisfy the relationship of the range (b) together with the range indicated by (a), the toner is made uniform. And can be pulverized to a small particle size.

The toner satisfying the above relationship can be obtained by melt-kneading a toner in which the viscosity of the release agent and the viscosity of the binder resin satisfy a certain range.
FIG. 2 is a graph showing the relationship between the viscosity Gr of the binder resin at 130 ° C. of the toner according to the present invention and the viscosity Gw of the release agent at 100 ° C. In FIG. 2, a region (B) is a range filled with the toner according to the present invention.
By melt-kneading the release agent viscosity and the binder resin viscosity satisfying the range (B), the dispersion state of the release agent in the binder resin is appropriately controlled, The release agent is uniformly dispersed. Therefore, the base toner obtained after melt-kneading has an average dispersion diameter Dw in a desired range, and the pulverization index F of the toner and the average dispersion diameter Dw of the release agent are expressed by the above formula (1), It can satisfy | fill the relationship of Formula (2).

Next, the configuration of the present invention will be described in more detail.
In the toner according to the present invention, the weight average particle diameter D4 is 2 to 4 μm, the average dispersion diameter Dw of the release agent is 0.05 to 0.3 μm, the weight average particle diameter D4 and the average dispersion diameter Dw of the release agent are In the toner satisfying the relationship of Dw ≦ 0.075 × D4, the grindability index F and the average dispersion particle diameter Dw of the release agent satisfy the relationship of F ≦ −40 × Dw + 19 and F ≦ 20 × Dw + 5.
When the pulverization index F of the toner exceeds a value of −40 × Dw + 19 with respect to the average dispersion diameter Dw of the release agent, crushing occurs inside the release agent or at the interface between the release agent and the binder resin. This tends to occur, and it becomes difficult to uniformly pulverize the toner composition at the binder resin portion.
That is, when the pulverization index F of the toner and the average dispersion diameter Dw of the release agent are outside the range indicated by (a) in FIG. The ratio of occurrence of crushing at the interface between the release agent and the binder resin increases, and the amount of the release agent exposed to the toner particle surface increases. In this case, even if the weight average particle diameter D4 and the average dispersion diameter Dw of the release agent satisfy the above desired relationship, the amount of the release agent exposed on the particle surface increases, and the toner fluidity is increased. In addition, the spent releasing agent is likely to be detached from the toner particles and adhere to the carrier surface. When the ratio of the carrier having the release agent attached to the surface increases, the chargeability as a developer decreases, and abnormal images such as background stains and toner scattering on the image are likely to occur, and the amount of toner to be developed The image density is likely to decrease due to the decrease in the image quality.
On the other hand, even if the pulverization index F of the toner and the average dispersion particle diameter Dw of the release agent satisfy the relationship of F ≦ −40 × Dw + 19, the value of the pulverization index F is the average dispersion particle diameter of the wax. When it exceeds 20 × Dw + 5 with respect to Dw, the pulverizability of the toner composition is impaired, and it becomes difficult to obtain a toner having a small particle diameter.

Further, the toner has a weight average particle diameter D4 of 2 to 4 μm.
When the weight average particle diameter of the toner exceeds 4 μm, the resolution of the minute spot is not sufficient, the scattering to the non-image portion is also large, and the image quality tends to be inferior.
On the other hand, when the weight average particle diameter D4 is less than 2 μm, problems such as contamination in the machine due to toner scattering, a decrease in image density in a low-humidity environment, and poor photoconductor cleaning are likely to occur when used for a long period of time. However, there is a problem that the cost becomes high.

The average dispersion diameter Dw of the release agent in the toner particles is 0.05 to 0.3 μm.
When the average dispersion diameter Dw of the release agent exceeds 0.3 μm, the exposed area of the release agent on the surface of the toner particles increases, the toner fluidity deteriorates, and the carrier and latent image inside the developing device are further carried. The spent phenomenon that adheres to the body is likely to occur.
On the other hand, when the average dispersion diameter Dw of the release agent is less than 0.05, it becomes difficult to obtain sufficient release properties to obtain hot offset resistance.

Furthermore, the average dispersion diameter Dw of the release agent in the toner particles is 0.075 × D4 or less with respect to the weight average particle diameter D4 of the toner.
When the average dispersion diameter Dw of the release agent is a value exceeding 0.075 × D4 with respect to the weight average particle diameter D4 of the toner, the ratio of the release agent exposed on the toner particle surface increases, and the toner The fluidity of the toner deteriorates, and the spent phenomenon that adheres to the carrier and the latent image carrier inside the developing machine is more likely to occur.
Since the average dispersion diameter Dw of the wax in the toner particles is in the range of 0.075 × D4 or less, even in the case of the small particle diameter toner having the weight average particle diameter D4 in the range of 2 to 4 μm, it is exposed on the toner particle surface. The ratio of the releasing agent to be used is small, and a state excellent in fluidity and durability is obtained, which is preferable.

Further, the viscosity Gw at 100 ° C. of the release agent is desirably 3 to 10 (mm ² / s), and the viscosity Gr (Pa · s) of the binder resin at 130 ° C. and the release agent The viscosity Gw (mm ² / s) at 100 ° C. preferably satisfies the relationship of the following formula (3).

(Equation 4)
(Gr / 1000) -5 ≦ Gw ≦ (Gr / 1000) +2 (3)

Since the viscosity Gw (mm ² / s) of the release agent at 100 ° C. and the viscosity Gr (Pa · s) of the binder resin at 130 ° C. satisfy the above relationship, the toner is pulverized after melt-kneading. A toner in which the property index F and the average dispersion diameter Dw of the release agent satisfy the relationship of the above formulas (1) and (2) is obtained.
In the toner obtained after melt-kneading, if the viscosity Gw (mm ² / s) at 100 ° C. of the release agent and the viscosity Gr (Pa · s) at 130 ° C. of the binder resin do not satisfy the above relationship, The average dispersion diameter of the release agent falls outside the desired range, or the balance between the toner pulverization index F and the average dispersion diameter Dw of the release agent is impaired, and the release agent and the binder resin are separated during pulverization. This is not preferable because the ratio of occurrence of crushing at the interface increases or, conversely, the pulverizability of the entire toner is deteriorated and a toner having a desired particle diameter cannot be obtained.
The measuring method of the viscosity at each temperature of the binder resin and the release agent will be described in detail in the following examples.

Further, the addition amount of the release agent is desirably 1 to 8 parts by weight with respect to 100 parts by weight of the binder resin.
If it is less than 1 part by weight, it is difficult to obtain releasability for improving offset resistance.
On the other hand, when the amount exceeds 8 parts by weight, it is difficult to disperse the release agent to the desired state, and the problem is that the fluidity deteriorates due to the increase in the total amount.

In the toner of the present invention, a wax can be used as a release agent, and the wax preferably has a main peak (Mp) measured by GPC of 1000 to 2500.
When Mp is less than 1000, the dispersed particle diameter of the wax in the toner particles becomes too small, and the blocking resistance also deteriorates.
If it exceeds 2500, the dispersed particle size becomes too large and the toner contains a large amount of free wax, and the toner on the photoreceptor remains insufficiently cleaned, resulting in image defects. There is.

  The main peak (Mp) of the wax contained in the toner of the present invention is the peak molecular weight having the largest peak intensity of the wax in the chromatogram obtained from GPC.

The molecular weight distribution of the wax was measured by gel permeation chromatography (GPC) under the following conditions.
Measuring device: GPC-150C (manufactured by Waters)
Column: GMH-HT 30 cm 2 series (manufactured by Tosoh Corporation)
Temperature: 135 ° C
Solvent: o-dichlorobenzene (0.1% ionol added)
Flow rate: 1.0 ml / min
Sample: 0.4ml injection of 0.15% sample

  Measurement is performed under the above conditions, and a molecular weight calibration curve prepared from 10 kinds of monodisperse polystyrene standard samples having a molecular weight is used in calculating the molecular weight of the sample. Furthermore, it calculates by converting into polyethylene by the conversion formula derived | led-out from the Mark-Houwink viscosity formula.

Moreover, it is preferable that ratio (Mw / Mn) of the weight average molecular weight (Mw) and number average molecular weight (Mn) of wax is 1.1-1.8.
When Mw / Mn exceeds 1.8, it is difficult to control the dispersed particle diameter of the wax, which is not preferable.

The toner of the present invention may contain two or more different types of wax.
When two or more different types of waxes are contained, the Mp of at least one type of wax may be 1000 to 2500 and Mw / Mn may be 1.1 to 1.8 in the molecular weight distribution measured by GPC. Preferably, the Mp of each wax is 1000 to 2500 and the Mw / Mn is 1.1 to 1.8.
If any of the waxes exceeds the range of Mp of 1000 to 2500 and Mw / Mn of 1.1 to 1.8, the dispersed particle size distribution of the wax in the toner particles becomes wide and difficult to control. There is not preferable.

The release agent contained in the toner of the present invention includes plant waxes such as candelilla wax, carnauba wax, rice wax, wax, jojoba oil, as well as synthetic waxes such as low molecular weight polyethylene and polypropylene. Animal waxes such as beeswax, lanolin and whale wax; mineral waxes such as montan wax and ozokerite; oil-based waxes such as hydrogenated castor oil, hydroxystearic acid, fatty acid amide, and phenol fatty acid ester can be used. These may be used alone or in admixture of two or more.
Among these, it is preferable to use natural wax such as ester wax having ester bond, candelilla wax, carnauba wax, rice wax, and montan wax. Furthermore, it is very preferable to use carnauba wax among ester waxes.

The toner has a weight average particle diameter of 2.0 to 4.0 μm and a ratio (D4 / Dn) of the weight average particle diameter (D4) to the number average particle diameter (Dn) of 1.00 to 1.40. It is preferable that
By using a toner having such a particle size and particle size distribution, it has excellent heat-resistant storage stability, low-temperature fixability, and hot offset resistance, and particularly excellent gloss when used in a full-color copying machine. Sex is obtained.
In general, it is said that the smaller the particle size of the toner, the more advantageous it is to obtain a high-resolution and high-quality image, but it is disadvantageous for transferability and cleaning properties. is there. In addition, when the weight average particle size is smaller than the range of the present invention, in the case of a two-component developer, the toner is fused to the surface of the magnetic carrier during a long period of stirring in the developing device, and the charging ability of the magnetic carrier is reduced. When used as a developer, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur.
On the contrary, when the weight average particle diameter of the toner is larger than the range of the present invention, it becomes difficult to obtain a high-resolution and high-quality image and the balance of the toner in the developer is performed. In many cases, the variation in toner particle size becomes large.
On the other hand, if D4 / Dn exceeds 1.40, the charge amount distribution becomes wide and the resolving power decreases, which is not preferable.
The method for measuring the average particle size and particle size distribution of the toner will be described in detail in the following examples.

The fine particle content of 1.0 μm or less of the toner is preferably 10% by number or less.
It is preferable to reduce the number of particles having a large specific surface area of 1.0 μm or less, which affects the fluidity, to 10% by number or less, in addition to the effect of dispersing the release agent, further improving fluidity and durability.

(Binder resin)
The toner of the present invention includes at least a binder resin, a colorant, a release agent, and a charge control agent. As the binder resin used in the toner of the present invention, all those conventionally used as the binder resin for toner are applied. Specifically, homopolymers of styrene such as polystyrene, polychlorostyrene, and polyvinyltoluene, and substituted products thereof; styrene / p-chlorostyrene copolymer, styrene / propylene copolymer, styrene / vinyltoluene copolymer, styrene / Vinyl naphthalene copolymer, styrene / methyl acrylate copolymer, styrene / ethyl acrylate copolymer, styrene / butyl acrylate copolymer, styrene / octyl acrylate copolymer, styrene / methyl methacrylate copolymer Styrene / ethyl methacrylate copolymer, styrene / butyl methacrylate copolymer, styrene / α-chloromethyl methacrylate copolymer, styrene / acrylonitrile copolymer, styrene / vinyl ethyl ether copolymer, styrene / Vinyl methyl ketone copolymer, steel Styrene copolymers such as styrene / butadiene copolymer, styrene / isoprene copolymer, styrene / acrylonitrile / indene copolymer, styrene / maleic acid copolymer, styrene / maleic acid ester copolymer; polymethyl methacrylate , Polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyvinyl butyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic A group petroleum resin, chlorinated paraffin, paraffin wax and the like can be mentioned, and these are used alone or in admixture of two or more.

(Coloring agent)
As the colorant, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, Yellow lead, Titanium yellow, Polyazo yellow, Oil yellow, Hansa yellow (GR, A, RN, R), Pigment yellow L, Benzidine yellow (G, GR), Permanent yellow (NCG), Vulcan fast yellow (5G, R) ), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Phi Se Red, parachlor ortho nitro Nirin Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R Brilliant Carmine 6B, Pogment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thio Indigo red B, thioindigo maroon, oil red, quinacridone red, pyrazolone red, Riazo Red, Chrome Vermillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), indigo, ultramarine blue, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Phthalo Cyanine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

(Charge control agent)
Known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified 4 Secondary ammonium salts or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Bontron 03 of a nigrosine dye, Bontron P-51 of a quaternary ammonium salt, Bontron S-34 of a metal-containing azo dye, E-82 of an oxynaphthoic acid metal complex, E-84 of a salicylic acid metal complex , Phenolic condensate E-89 (above, Orient Chemical Industries, Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy Charge PSY VP2038, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit) Manufactured), copper phthalocyanine, perylene, quinacridone, azo series Fee, a sulfonic acid group, a carboxyl group, and polymer compounds having a functional group such as quaternary ammonium salts.

(External additive)
Inorganic fine particles are preferably used as an external additive for assisting the fluidity, developability and chargeability of the toner particles. The primary particle diameter of the inorganic fine particles is preferably 5 × ¹⁰ -3 ~2μm, it is particularly preferably 5 × ¹⁰ -3 ~0.5μm. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The amount of the inorganic fine particles added is preferably 0.01 to 5 wt% of the toner, and particularly preferably 0.01 to 2.0 wt%.
Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, quartz sand, clay, mica, wollastonite, diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.
Such an external additive can be surface-treated to increase hydrophobicity and prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents, silane coupling agents having a fluoroalkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils and the like are preferable surface treatment agents. .

(Melt kneading method)
As an example of the method for producing the toner according to the present invention, first, the binder resin, the pigment or dye as the colorant, the release agent, the charge control agent, other additives, etc. are mixed in a mixer such as a Henschel mixer. After mixing thoroughly, continuous twin-screw extruder, for example, KTK type twin screw extruder manufactured by Kobe Steel, TEM type twin screw extruder manufactured by Toshiba Machine Co., Ltd., PCM type twin screw extruder manufactured by Ikekai Tekko Co., Ltd. The constituent materials are well kneaded using a KEX type twin screw extruder manufactured by Kurimoto Iron Works, or a continuous single screw kneader, for example, a thermal kneader such as a bush kneader or a KCK kneader. At this time, as a method for increasing the specific energy, a method of decreasing the kneading amount or a method of lowering the kneader setting temperature and kneading the kneaded material in a high viscosity state is used.
Next, after cooling the kneaded product, it is coarsely pulverized using a hammer mill or the like, and further pulverized by a fine pulverizer or mechanical pulverizer using a jet stream, and a classifier using a swirling air stream or the Coanda effect is used. The toner of the present invention is obtained by classifying to a predetermined particle size using a classifier.
In addition, it can also be produced by various production methods such as a suspension polymerization method, a dispersion polymerization method and an emulsion polymerization method, and known production methods such as a microcapsule polymerization method and a spray drying method.
Next, there is a method in which the inorganic fine powder and the toner are sufficiently mixed by a mixer such as a Henschel mixer and then passed through a sieve of 250 mesh or more to remove coarse particles and agglomerated particles to obtain a toner.

  The toner of the present invention can be used as a two-component developer toner used by mixing with a magnetic carrier, or as a one-component developer toner that does not use a magnetic carrier.

  As the magnetic carrier used in combination with the toner of the present invention, conventionally known carriers for two-component developers can be used, for example, carriers made of magnetic particles such as iron and ferrite, such as A resin-coated carrier obtained by coating various magnetic particles with a resin, or a binder-type carrier obtained by dispersing magnetic fine powder in a binder resin can be used. Among these carriers, a silicone resin, a copolymer resin (graft resin) of an organopolysiloxane and a vinyl monomer, or a resin-coated carrier using a polyester resin can be used as a coating resin. A carrier coated with a resin obtained by reacting an isocyanate with a copolymer resin of an organopolysiloxane and a vinyl monomer is preferable from the viewpoint of durability, environmental stability, and spent resistance. . As the vinyl monomer, it is necessary to use a monomer having a substituent such as a hydroxyl group reactive with isocyanate. In addition, it is preferable to use a magnetic carrier having a volume average particle diameter of 20 to 100 μm, preferably 20 to 60 μm from the viewpoint of ensuring high image quality and preventing carrier fogging.

  EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited thereto. In the following, “part” means part by weight, and “%” means weight%.

Examples of the synthesis of the binder resin used in the production of the toner of the present invention are shown below.
[Synthesis Example of Polyester Resin 1]
443 parts of PO adduct of bisphenol A (hydroxyl value 320), 135 parts of diethylene glycol, 422 parts of terephthalic acid, and 2.5 parts of dibutyltin oxide are placed in a reaction vessel equipped with a thermometer, stirrer, cooler and nitrogen introduction tube. The polyester resin 1 was obtained by reacting at 230 ° C. until the acid value reached 7. Polyester resin 1 had a Tg of 65 ° C. and a peak molecular weight of 16000. The grindability index of the polyester resin 1 was 8.8.

[Synthesis example of polyester resin 2]
750 parts of an EO adduct of bisphenol A (hydroxyl value 340), 250 parts of terephthalic acid, and 2.5 parts of dibutyltin oxide were placed in a reaction vessel equipped with a thermometer, a stirrer, a cooler, and a nitrogen introduction tube. After reacting until the acid value reached 6, the reaction product was taken out and cooled rapidly to obtain polyester resin 2. Polyester resin 2 had a Tg of 70 ° C. and a peak molecular weight of 20,500. The grindability index of the polyester resin 2 was 10.5.

[Synthesis Example of Styrene Acrylic Resin 1]
Into an autoclave reaction vessel equipped with a thermometer, a stirrer, and a nitrogen introduction tube, 646 parts of xylene were placed, and after nitrogen substitution, a mixed monomer of 200 parts of acrylonitrile, 689 parts of styrene, 114 parts of acrylate-2-ethylhexyl, and 118 parts of xylene, An initiator solution of 52 parts of di-t-butyl peroxide was added dropwise at 170 ° C. over 3 hours to remove the solvent, whereby a thylene acrylic resin 1 was obtained. The weight average molecular weight of the styrene acrylic resin 1 was 4,700, the number average molecular weight was 2,300, and Tg was 55 ° C. The grindability index of the styrene acrylic resin 1 was 2.1.

[Synthesis Example of Hybrid Resin 1]
A mixture of 332 g of styrene, 83 g of 2-ethylhexyl acrylate, 8 g of acrylic acid (both reactive compounds) and 42 g of dicumyl peroxide (polymerization initiator), 700 g of propylene oxide 2.2 mol adduct of bisphenol A, 166 g of terephthalic acid Then, 107 g of isododecenyl succinic anhydride and 115 g of trimellitic acid and 20 g of dibutyltin oxide (esterification catalyst) were added dropwise at 160 ° C. over 1 hour in a nitrogen atmosphere. While maintaining at 160 ° C., the reaction was further continued for 2 hours, and then the temperature was raised to 230 ° C. and further reacted under reduced pressure to obtain hybrid resin 1. Hybrid resin 1 had a softening point of 143.2 ° C., a glass transition point of 65.5 ° C., an acid value of 26.2 mgKOH / g, and a THF-insoluble content of 23.2%. The grindability index of the hybrid resin 1 was 7.1.

[Synthesis Example of Hybrid Resin 2]
As raw material monomers for the polycondensation resin, 1225 g of polyoxypropylene (2.2) -2,2- (4-hydroxyphenyl) propane, polyoxyethylene (2.0) -2,2- (4-hydroxyphenyl) 485 g of propane, 345 g of terephthalic acid, 250 g of isododecenyl succinic acid and 5 g of dibutyltin oxide as an esterification catalyst were subjected to condensation polymerization at 230 ° C. for 6 hours in a nitrogen atmosphere, and then cooled to 160 ° C. After adding 175 g of trimellitic acid to the reaction vessel, 476 g of styrene, 105 g of 2-ethylhexyl acrylate, 35 g of acrylic acid as both reactive compounds and 25 g of dicumyl peroxide as a polymerization initiator are added as raw material monomers for the addition polymerization resin. The mixture was added dropwise over 1 hour with stirring at 160 ° C., and the addition polymerization reaction was carried out while maintaining the same temperature for 1 hour, and then the temperature was raised to 200 ° C. to perform the condensation polymerization reaction. The reaction was carried out until the softening point measured by ASTM E28-67 reached 120 ° C. to obtain hybrid resin 2. Hybrid resin 2 had a Tg of 58 ° C. and an acid value of 22.5 mgKOH / g. The grindability index of the hybrid resin 2 was 4.8.

[Synthesis example of hydrogenated petroleum resin 1]
A mixture of 269 g of dicyclopentadiene and 269 g of styrene was added over 2 hours while stirring and heating to 230 ° C. in a 1 liter autoclave equipped with a stirrer substituted with nitrogen. Thereafter, the reaction solution was heated to 260 ° C. over 105 minutes and reacted for 4 hours. After completion of the reaction, the reaction product solution is taken out and treated with a rotary evaporator at a temperature of 200 ° C. and a pressure of 10 mmHg for 3 hours to remove unreacted monomers and xylene, and a copolymer of 510 g of dicyclopentadiene and styrene is obtained. Obtained. The softening point of this resin A was 115 ° C., the aromatic ring content (styrene basis) was 43% by weight, and the bromine value was 54 g / 100 g.
Furthermore, in a 300 ml autoclave equipped with a stirrer substituted with nitrogen, 75 g of cyclohexane, 75 g of resin A, 4.0 g of 0.5 wt% palladium-supported silica-alumina catalyst were charged, and hydrogenated at a hydrogen pressure of 4 MPa and a temperature of 150 ° C. for 2 hours. Reaction was performed. The reaction product was taken out after cooling and filtered to remove the catalyst, and then the solvent was removed by distillation to obtain hydrogenated petroleum resin 1. Hydrogenated petroleum resin 1 has a softening point of 120 ° C., an aromatic ring content (based on styrene) of 43% by weight, a bromine number of 14 g / 100 g, an ethylenic double bond hydrogenation rate of 74%, and an aromatic ring hydrogenation rate. Was 0%. The grindability index of the hydrogenated petroleum resin 1 was 0.5.

Hereinafter, a synthesis example of the master batch used for the production of the toner according to the present invention will be shown.
Water ・ ・ ・ 25 parts Carbon black (Mitsubishi Chemical # C-44) ・ ・ ・ ・ 50 parts Polyester resin (consisting of PO, EO adduct of bisphenol A and terephthalic acid, Tg60 ℃, Mw25000, Mp115 ℃ linear Polyester) 50 parts The above toner constituent materials were mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd., 1500 rpm for 3 minutes), and the mixture was kneaded at 120 ° C. for 45 minutes using two rolls. Then, the mixture was cooled and rolled, and pulverized with a pulverizer to obtain a master batch 1.
Masterbatches of other colors were similarly prepared except that the colorant was changed to the following instead of carbon black.
Yellow colorant: benzimidazolone pigment (Pigment Yellow 180, Novoper Yellow P-HG manufactured by Clariant)
Magenta colorant: quinacridone pigment (Pigment Red 146, 147, Permanent Rubine F6B manufactured by Clariant)
Cyan colorant: Copper phthalocyanine pigment (Pigment Blue 15: 3, Lionol Blue 7351, Toyo Ink Co., Ltd.)

Example 1
Polyester resin 1 ... 47.5 parts by weight Styrene acrylic resin 1 ... 47.5 parts by weight Paraffin wax (Nippon Seiki: 120) ... 5 parts by weight Masterbatch 1 ... 10 Part by weight The above toner constituent materials are mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd., at 1500 rpm for 3 minutes), and then uniaxial kneader (Buss small bus co-kneader) under the following conditions. Kneading was performed (set temperature: inlet portion 100 ° C., outlet portion 50 ° C., feed amount: 2 kg / Hr) to obtain [base toner 1].
Further, the [base toner 1] was kneaded, cooled by rolling, pulverized by a pulverizer, and further an I-type mill (IDS-2 type manufactured by Nippon Pneumatic Co., Ltd., using a flat impact plate, air pressure: 6.8 atm). / Cm ² , feed amount: 0.5 kg / hr) were further pulverized and further classified (132MP manufactured by Alpine) to obtain [Toner Base Particles 1].
Thereafter, 100 parts by weight of [toner base particle 1], 1.0 part by weight of hydrophobic silica (external additive A) having a primary particle size of 10 nm as an external additive, a primary particle size of 110 nm produced by a sol-gel method, and substantially spherical. 1.5 parts by weight of hexamethyldisilazane hydrophobized silica (external additive B) and 1.0 part of hydrophobic titanium oxide (external additive C) having a primary particle size of 15 nm were added to a Henschel mixer (Henschel manufactured by Mitsui Mining Co., Ltd.). 20B) to obtain a toner.
Mixing conditions were set by repeating the set of rotating for 30 seconds and stopping rotation for 60 seconds 5 times at a peripheral speed of 30 m / sec.
The toner obtained here is referred to as [Toner 1].
[Toner 1] had a weight average particle diameter (D4) of 3.8 μm and a number average particle diameter (Dn) of 3.1 μm. Further, the average dispersed particle size (Dw) of the wax of [Toner 1] was 0.28 μm.

(Example 2)
Polyester resin 1 ... 75 parts by weight Styrene acrylic resin 1 ... 20 parts by weight Paraffin wax (Nippon Seiki: 140) ... 5 parts by weight Masterbatch 1 ... 10 parts by weight The above toner The constituent materials were mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd., at 1500 rpm for 3 minutes), and further kneaded under the same conditions as in Example 1 to obtain [Base toner 2].
Thereafter, [Mother toner 2] is finely pulverized and classified by the same method as in Example 1 to obtain [Mother toner particles 2], and then [Mother toner particles 2] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 2].
[Toner 2] had a weight average particle diameter (D4) of 3.0 μm and a number average particle diameter (Dn) of 2.4 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.24 μm.

(Example 3)
Polyester resin 1 ・ ・ ・ 65 parts by weight Styrene acrylic resin 1 ・ ・ ・ 30 parts by weight Paraffin wax (manufactured by Nippon Seiki: 130) ・ ・ ・ 6 parts by weight Masterbatch 1 ・ ・ ・ 10 parts by weight (Mitsui Mining Co., Ltd. Henschel 20B at 1500 rpm for 3 minutes) and kneading under the same conditions as in Example 1 to obtain [Base toner 3].
Thereafter, [Mother toner 3] is finely pulverized and classified by the same method as in Example 1 to obtain [Mother toner particles 3], and then [Mother toner particles 3] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 3].
[Toner 3] had a weight average particle diameter (D4) of 2.3 μm and a number average particle diameter (Dn) of 1.8 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.20 μm.

Example 4
Hybrid resin 1 ··· 95 parts by weight Paraffin wax (Nippon Seiki 155) ··· 4 parts by weight Masterbatch 1 ··· 10 parts by weight Henschel 20B at 1500 rpm for 3 minutes) and kneading under the same conditions as in Example 1 to obtain [Mother toner 4].
Thereafter, [Mother toner 4] is pulverized and classified by the same method as in Example 1 to obtain [Mother toner particles 4], and then [Mother toner particles 4] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 4].
[Toner 4] had a weight average particle diameter (D4) of 3.7 μm and a number average particle diameter (Dn) of 2.9 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.14 μm.

(Example 5)
Hybrid resin 2 ... 95 parts by weight Microcrystalline wax (Nippon Seiki: Hi-MiC2065)
7 parts by weight Master batch 1 10 parts by weight The above toner constituent materials were mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd. for 3 minutes at 1500 rpm), and the same conditions as in Example 1 were obtained. Then, kneading was carried out to obtain [Base toner 5].
Thereafter, [Mother toner 5] is pulverized and classified in the same manner as in Example 1 to obtain [Mother toner particles 5], and then [Mother toner particles 5] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 5].
[Toner 5] had a weight average particle diameter (D4) of 2.3 μm and a number average particle diameter (Dn) of 1.9 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.07 μm.

(Example 6)
Polyester resin 2 ... 47.5 parts by weight Hydrogenated petroleum resin 1 ... 47.5 parts by weight Paraffin wax (Nippon Seiki: 120) ... 5 parts by weight
Master batch 1... 10 parts by weight The above toner constituent materials are mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd., at 1500 rpm for 3 minutes) and kneaded under the same conditions as in Example 1. Toner 6] was obtained.
Thereafter, [Mother toner 6] is finely pulverized and classified by the same method as in Example 1 to obtain [Mother toner particles 6]. Then, [Mother toner particles 6] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 6].
[Toner 6] had a weight average particle diameter (D4) of 3.4 μm and a number average particle diameter (Dn) of 2.6 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.20 μm.

(Example 7)
Polyester resin 2 ... 70 parts by weight Hydrogenated petroleum resin 1 ... 25 parts by weight Fischer-Tropsch wax (Nippon Seiki: FT-0070) ... 6 parts by weight Master batch 1 ... 10 Part by weight The above toner constituent materials were mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd., at 1500 rpm for 3 minutes) and kneaded under the same conditions as in Example 1 to obtain [Mother toner 7].
Thereafter, [Mother toner 7] is finely pulverized and classified by the same method as in Example 1 to obtain [Mother toner particles 7]. Then, [Mother toner particles 7] are obtained in the same manner as in Example 1. An external additive was mixed to obtain [Toner 7].
[Toner 7] had a weight average particle diameter (D4) of 3.8 μm and a number average particle diameter (Dn) of 3.0 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.27 μm.

(Comparative Example 1)
Polyester resin 1 ... 95 parts by weight Microcrystalline wax (Nippon Seiki: Hi-MiC2065) ... 6 parts by weight Masterbatch 1 ... 10 parts by weight (Henshell 20B manufactured by the company) at 1500 rpm for 3 minutes) and kneaded under the same conditions as in Example 1 to obtain [Base toner 8].
Thereafter, [Mother toner 8] is finely pulverized and classified in the same manner as in Example 1 to obtain [Mother toner particles 8], and then [Mother toner particles 8] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 8].
[Toner 8] had a weight average particle diameter (D4) of 4.3 μm and a number average particle diameter (Dn) of 3.5 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.17 μm.

(Comparative Example 2)
Polyester resin 1 ... 95 parts by weight Fischer-Tropsch wax (Nippon Seiki: FT-0070) ... 5 parts by weight Masterbatch 1 ... 10 parts by weight (Henshell 20B manufactured by KK) at 1500 rpm for 3 minutes, and kneaded under the same conditions as in Example 1 to obtain [Base toner 9].
Thereafter, [Mother toner 9] is pulverized and classified in the same manner as in Example 1 to obtain [Mother toner particles 9], and then [Mother toner particles 9] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 9].
[Toner 9] had a weight average particle diameter (D4) of 3.7 μm and a number average particle diameter (Dn) of 2.1 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.30 μm.

(Comparative Example 3)
Polyester resin 2 ... 95 parts by weight Paraffin wax (Nippon Seiki: 120) ... 5 parts by weight Masterbatch 1 ... 10 parts by weight The above toner constituent materials are mixed with a Henschel mixer (Mitsui Mining Co., Ltd.). Of Henschel 20B at 1500 rpm for 3 minutes) and kneading under the same conditions as in Example 1 to obtain [Base toner 10].
Thereafter, [Base toner 10] is pulverized and classified by the same method as in Example 1 to obtain [Toner base particle 10], and then [Toner base particle 10] is obtained in the same manner as in Example 1. An external additive was mixed to obtain [Toner 10].
[Toner 10] had a weight average particle diameter (D4) of 3.0 μm and a number average particle diameter (Dn) of 1.8 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.24 μm.

(Comparative Example 4)
Polyester resin 2 ... 80 parts by weight Styrene acrylic resin 1 ... 15 parts by weight Paraffin wax (Nippon Seiki: 120) ... 5 parts by weight Master batch 1 ... 10 parts by weight The above toner The constituent materials were mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd., at 1500 rpm for 3 minutes) and kneaded under the same conditions as in Example 1 to obtain [Base toner 11].
Thereafter, [Mother toner 11] is pulverized and classified by the same method as in Example 1 to obtain [Mother toner particles 11], and then [Mother toner particles 11] are obtained in the same manner as in Example 1. An external additive was mixed to obtain [Toner 11].
[Toner 11] had a weight average particle diameter (D4) of 2.5 μm and a number average particle diameter (Dn) of 1.6 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.21 μm.

(Comparative Example 5)
Polyester resin 1 ... 80 parts by weight Styrene acrylic resin 1 ... 15 parts by weight Microcrystalline wax (Nippon Seiki: Hi-MiC1080) ... 5 parts by weight Masterbatch 1 ... 10 parts by weight Part The above toner constituent materials were mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd., at 1500 rpm for 3 minutes) and kneaded under the same conditions as in Example 1 to obtain [Base toner 12].
Thereafter, [Mother toner 12] is pulverized and classified by the same method as in Example 1 to obtain [Mother toner particles 12], and then [Mother toner particles 12] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 12].
[Toner 12] had a weight average particle diameter (D4) of 2.5 μm and a number average particle diameter (Dn) of 1.6 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.21 μm.

(Comparative Example 6)
Polyester resin 2 ... 25 parts by weight Styrene acrylic resin 1 ... 70 parts by weight Microcrystalline wax (manufactured by Nippon Seiki: Hi-MiC1080) ... 5 parts by weight
Master batch 1... 10 parts by weight The above toner constituent materials are mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd., at 1500 rpm for 3 minutes) and kneaded under the same conditions as in Example 1. Toner 13] was obtained.
Thereafter, [Mother toner 13] is finely pulverized and classified by the same method as in Example 1 to obtain [Mother toner particles 13]. Then, [Mother toner particles 13] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 13].
[Toner 13] had a weight average particle diameter (D4) of 3.0 μm and a number average particle diameter (Dn) of 2.2 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.10 μm.

(Comparative Example 7)
Polyester resin 1 ... 47.5 parts by weight Styrene acrylic resin 1 ... 47.5 parts by weight Paraffin wax (Nippon Seiki: 115) ... 5 parts by weight Masterbatch 1 ... 10 Part by weight The above toner constituent materials were mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd., at 1500 rpm for 3 minutes) and kneaded under the same conditions as in Example 1 to obtain [Base toner 14].
Thereafter, [Mother toner 14] is pulverized and classified in the same manner as in Example 1 to obtain [Mother toner particles 14], and then [Mother toner particles 14] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 14].
[Toner 14] had a weight average particle diameter (D4) of 4.0 μm and a number average particle diameter (Dn) of 3.2 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.33 μm.

(Comparative Example 8)
Polyester resin 1 ... 47.5 parts by weight Polyester resin 2 ... 47.5 parts by weight Microcrystalline wax (Nippon Seiki: Hi-MiC2065) ... 5 parts by weight Masterbatch 1 ... 10 parts by weight The above toner constituent materials were mixed with a Henschel mixer (Henschel 20B manufactured by Mitsui Mining Co., Ltd., at 1500 rpm for 3 minutes) and kneaded under the same conditions as in Example 1 to obtain [Base toner 15]. .
Thereafter, [Mother toner 15] is pulverized and classified by the same method as in Example 1 to obtain [Mother toner particles 15], and then [Mother toner particles 15] are obtained in the same manner as in Example 1. External additives were mixed to obtain [Toner 15].
[Toner 15] had a weight average particle diameter (D4) of 3.3 μm and a number average particle diameter (Dn) of 2.2 μm. Further, the average dispersed particle size (Dw) of the wax of the toner was 0.27 μm.

Table 1 shows the composition and characteristics of the binder resins of [Toner 1] to [Toner 15] described above, and Table 2 shows the particle diameter and pulverization index of the toner, and the characteristics of the wax contained in each toner. And the average dispersion diameter.
Evaluation items and evaluation methods are as follows.

[Evaluation item]
(1) Toner weight average particle diameter D4, number average particle diameter Dn
A Coulter Counter TA-II (manufactured by Coulter, Inc.) was used as an apparatus for measuring the particle size distribution of toner particles. The measurement method is described below.
First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of an aqueous electrolytic solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using primary sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 22 μm aperture as an aperture. Volume distribution and number distribution are calculated. From the obtained distribution, the weight average particle diameter (D4) and the number average particle diameter (Dn) of the toner can be obtained.
As channels, 1.26 to less than 1.59 μm; 1.59 to less than 2.00 μm; 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4 0.000 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6.35 to less than 8.00 μm; 8.00 to less than 10.08 μm; 10.08 to less than 12.70 μm; Uses 12 channels of less than 00 μm; less than 16.00 to less than 20.20 μm, and targets particles having a particle size of 1.26 μm to less than 20.20 μm.
(2) Toner pulverization index: 200 kg of resin is kneaded for 15 minutes with a small two roll (Nishimura Co., Ltd.) heated to 110 ° C., then charged into Hosokawa Micron Rotoplex and coarsely pulverized resin particles for 5 minutes To obtain a resin powder that passes through 16 mesh and does not pass through 20 mesh.
10.00 g of this classified resin powder is precisely weighed, pulverized with a mill and mixer MM-I type (manufactured by Hitachi Living Supply Co., Ltd.) for 30 seconds, passed through a 30 mesh sieve, and the weight of the resin not passing (R ) G is precisely weighed, and the residual ratio is obtained from the value of R according to the following formula (I), and this operation is performed three times and the average is obtained as the grindability index.
Millability index F = ((R) g / resin weight before grinding (10.00 g)) × 100 (I)
(3) Average Dispersion Particle Size of Wax In this example, the particle size in the maximum direction of the wax was used as the wax dispersion particle size.
Specifically, the toner is embedded in an epoxy resin, cut into an ultrathin section of about 100 μm, dyed with ruthenium tetroxide, and then the cross section of the toner is observed with a transmission electron microscope (TEM) at a magnification of 10,000 times. Images were taken and 20 photographs (20 toners) were evaluated to observe the dispersion state of the wax and the dispersion diameter was measured. In the case of an irregular shape, the average value of the longest diameter and the shortest diameter was used.
(4) Viscosity of wax The viscosity Gw of the wax is measured using a rotational viscometer.
As the viscometer, VT-500 (manufactured by HAAKE) was used, and the value measured under the following conditions was taken as the melt viscosity.
Measurement temperature: 100 ° C
Sample: 10-50mg
Cone used (cone): HAAKE PK1; 0.5
Stress: 1/6000 sec
(5) Viscosity of Binder Resin The viscosity Gr of the binder resin is determined by using a flow tester (CFT-500 type, manufactured by Shimadzu Corporation), a load of 10 kg / cm ² , an orifice diameter of 1 mm × length of 1 mm, and a heating rate of 5 ° C. / A method of reading the viscosity at 130 ° C. in minutes was adopted.

The wax average dispersion diameter Dw and grindability index F of the toners of Examples 1 to 7 and Comparative Examples 1 to 8 shown in Table 2 are shown as “O” for the toners of Examples 1 to 7, and Comparative Example. The toners 1 to 8 are indicated by “x” and plotted in the graph of FIG.
In addition, the viscosity Gr (see Table 1) of the binder resin at 130 ° C. and the viscosity Gw (see Table 2) of the release agent at 100 ° C. for the toners of Examples 1 to 7 and Comparative Examples 1 to 8. The values are plotted in the graph of FIG. 2 with “◯” for the toners of Examples 1 to 7 and “X” for the toners of Comparative Examples 1 to 8.

Next, 7 wt% of the toner and 93 wt% of a ferrite carrier having an average particle diameter of 35 μm coated with a silicone resin with an average thickness of 0.5 μm are mixed for 10 minutes by a tumbler mixer, and yellow, magenta, cyan, and black are mixed. A two-component developer was prepared.
Using the obtained two-component developer, development was performed with Imagio NeoC285 manufactured by Ricoh, and the fixing properties (fixing minimum temperature and fixing maximum temperature) of the image printed on Ricoh type 6200 paper were evaluated. Furthermore, 100,000 sheets were printed with an image area ratio of 5% for each color, and the image quality (image density, background stain density) printed on the Ricoh type 6200 and developer matching quality (developer charge amount, developer toner density) ) Was evaluated. Evaluation methods and evaluation criteria are as follows.

[Evaluation item]
<Degree of aggregation>
Measurement was performed using a powder tester (PT-N type, manufactured by Hosokawa Micron Corporation). Specifically, 2.0 g of toner was measured by passing it through a sieve (plain woven wire mesh, standard JIS Z8801-1) having an aperture of 150 μm, 75 μm, and 45 μm under vibration conditions with an amplitude of 1 mm and a vibration time of 30 seconds. The amount of residual toner on each sieve after vibration was measured and calculated using the following formula (4).
Aggregation degree (%) = (X + 0.6 × Y + 0.2 × Z) /2.0×100 (4)
(However, X: toner remaining amount (g) on a sieve having an opening of 150 μm, Y: toner remaining amount (g) on a sieve having an opening of 75 μm, Z: toner remaining amount (g) on a sieve having an opening of 45 μm) )
In this embodiment, the degree of aggregation is used as an index indicating fluidity.
When the degree of aggregation obtained by the above method is 20% or less, the fluidity required for the toner can be exhibited.
Further, when the degree of aggregation is 15% or less, sufficient fluidity as a toner can be exhibited.
<Image density>
Using a Macbeth densitometer, the density of the solid solid portion was measured at five points, and the measured values were averaged to obtain the image density.
<Skin dirt concentration>
At the time of development, the density of the portion corresponding to the non-image portion on the photoreceptor was measured. After adhering and peeling the printerac to the photoconductor, it adheres to Ricoh type 6200 paper (white paper) and measures the density at five points with a Macbeth densitometer to calculate the average value. From this average value, the printerac only The value obtained by subtracting the density adhered to the white paper was defined as the background stain density.
<Developer charge amount, toner concentration>
The charge amount is measured using a blow-off powder charge amount measuring device (Toshiba Chemical Co., Ltd.), placed in a measurement gauge set with a mesh of 635 mesh, blown off for 30 seconds, and the charge amount Q (μC) of the scattered powder. And the mass M (g) are measured, and the developer charge amount Q / M (μC / g) and the toner concentration TC (wt%) are obtained from the charge amount Q (μC) and the mass M (g).
When the value of the charge amount obtained by the above method is in the range of 30 to 50 μC / g, the occurrence of abnormal images on the image after fixing is suppressed, and the density reduction of the obtained image is also suppressed. Stable development characteristics can be obtained in the developing device.
<Fixing lower limit temperature and fixing upper limit temperature>
The surface temperature of the belt of the fixing device mounted on Imagio NeoC285 (manufactured by Ricoh) is changed every 5 ° C. within a range of 130 to 210 ° C., so that the toner adhesion amount becomes 0.50 ± 0.03 mg / cm ^2. In addition, solid images were printed and the fixing characteristics were evaluated.
The minimum fixing temperature was determined as the fixing belt temperature at which the residual ratio of the image density after rubbing the obtained fixed image with a pad was 70% or more. The fixing upper limit temperature was set to an upper limit temperature at which no offset occurs.

Table 3 shows the evaluation results of the toner.
Table 3 shows the evaluation results of cyan toner as a representative of each color.

As is apparent from Table 3, the toner according to the present invention has excellent fluidity and maintains a stable chargeability as a developer even when used over time, such as a decrease in image density and background stains. A high-quality image with no abnormal images was obtained.
On the other hand, although the toners of Comparative Examples 1 to 8 are excellent in fixability, the fluidity is deteriorated, and the amount of charge as a developer is reduced due to use over time. Decrease in density and generation of background stains were observed, resulting in poor image quality.

FIG. 6 is a diagram showing a relationship between a pulverizability index F of a toner according to the present invention and an average dispersion diameter Dw of a release agent. It is a figure which shows the relationship between the viscosity Gr of the binder resin at 130 degreeC of the toner which concerns on this invention, and the viscosity Gw of a mold release agent at 100 degreeC.

Claims (10)

In a toner containing at least a binder resin and a release agent,
The toner has a weight average particle diameter D4 of the toner and an average dispersed particle diameter Dw of the release agent in the toner.
(A) 2 ≦ D4 ≦ 4 (μm)
(B) 0.05 ≦ Dw ≦ 0.3 (μm)
(C) Dw ≦ 0.075 × D4
Toner satisfying the relationship
The toner characterized in that the pulverizability index F of the toner and the average dispersion particle diameter Dw of the release agent satisfy the relationship of the following formulas (1) and (2).
F ≦ −40 × Dw + 19 (1) F ≦ 20 × Dw + 5 (2) The toner according to claim 1.
The release agent has a viscosity Gw at 100 ° C. of 3 to 10 (mm ² / s),
A toner in which the viscosity Gr (Pa · s) at 130 ° C. of the binder resin and the viscosity Gw (mm ² / s) at 100 ° C. of the release agent satisfy the relationship of the following formula (3): .
(Gr / 1000) -5 ≦ Gw ≦ (Gr / 1000) +2 (3) The toner according to claim 1 or 2,
The release agent includes a wax having a main peak at a molecular weight of 1000 to 2500, and a ratio of the weight average molecular weight Mw to the number average molecular weight Mn (Mw / Mn) is 1.3 to 1.8. Toner. The toner according to any one of claims 1 to 3,
The toner according to claim 1, wherein the release agent is carnauba wax. In the toner according to any one of claims 1 to 4,
The amount of the release agent added is 1 to 8 parts by weight with respect to 100 parts by weight of the binder resin. The toner according to any one of claims 1 to 5,
The toner is obtained by kneading and then pulverizing a toner composition containing at least the binder resin, the release agent, and a colorant. The toner according to any one of claims 1 to 6,
The fine particle content of 1.0 μm or less of the toner is 10% by number or less.
Toner characterized by the above. The toner according to any one of claims 1 to 7,
The toner has a weight average particle diameter of 2.0 to 4.0 μm and a ratio (D4 / Dn) of the weight average particle diameter (D4) to the number average particle diameter (Dn) of 1.00 to 1.40. In range
Toner characterized by the above. In the developer for developing the electrostatic latent image formed on the latent image carrier,
The developer is a one-component developer using the toner according to any one of claims 1 to 8.
A developer characterized by that. In the developer for developing the electrostatic latent image formed on the latent image carrier,
The developer is a two-component developer comprising a magnetic carrier and the toner according to claim 1.
A developer characterized by that.

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