JP2010282146A - Toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner providing a uniform image without image unevenness and having good fixability while preventing offset. <P>SOLUTION: The toner contains: toner particles containing at least a binder resin, a colorant and a release agent; and an inorganic fine powder, and is characterized in that: the toner contains the release agent in an amount of 5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin; when the toner is heated at 190, the toner shows an adhesion strength of 50 N/m<SP>2</SP>or more and 500 N/m<SP>2</SP>or less; and in a weight average molecular weight (Mw) and an inertial square radius (Rw) determined by dissolving the toner in ortho-dichlorobenzene followed by shaking at 25°C for 24 hours to obtain a soluble content of the toner, and measuring the soluble content by use of size exclusion chromatography-online-multiangle laser light scattering (SEC-MALLS), the weight molecular weight (Mw) is 50,000 or more and 200,000 or less, and a ratio (Rw/Mw) of the inertial square radius (Rw) to the weight average molecular weight (Mw) satisfies the relationship of 1.0×10<SP>-4</SP>≤Rw/Mw≤4.0×10<SP>-4</SP>. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a toner used in a recording method using electrophotography or the like.

Many methods are known as electrophotographic methods. In general, an electrostatic latent image is formed on an electrostatic charge image carrier (hereinafter also referred to as a “photosensitive member”) by using a photoconductive substance by various means. Form. Next, the latent image is developed with toner to form a visible image. If necessary, the toner image is transferred onto a recording medium such as paper, and then the toner image is fixed on the recording medium with heat or pressure, and a copy. Is what you get. Examples of such an image forming apparatus include a copying machine and a printer.
In recent years, these printers and copiers have moved from analog to digital, and there is a strong demand for so-called “high image quality” that has excellent reproducibility of latent images and high resolution, and is free from scattering and unevenness.
Here, when considering unevenness, paper has irregularities derived from fibers, and the toner tends to be pushed down at the time of fixing in the convex portion, so that the density becomes low, whereas the density tends to be high in the concave portion. Further, in the concave portion, sufficient pressure and heat are hardly transmitted during fixing, so that the toner is likely to be insufficiently melted and gloss is likely to be lowered. For this reason, density differences and gloss differences due to minute unevenness of the paper cause unevenness of the image. Such unevenness is noticeable in a halftone image using so-called “rough paper” in which the paper is not smooth. In addition, such rough paper is difficult to fix toner, and there is a demand for improvement in fixability.

On the other hand, as an improvement from the fixing device, the pressure at the time of fixing, the pressure distribution, and the fixing temperature are controlled to improve unevenness and fixability.
On the other hand, improvement with toner has also been attempted with respect to fixability, and a toner having excellent low-temperature fixability and storage stability has been proposed by a toner having a core-shell structure using a polyfunctional ester compound (see Patent Document 1). ). Furthermore, a toner having a relatively high molecular weight and a high-solubility in styrene that can be fixed at low temperature and has excellent storage stability and fluidity has been proposed (see Patent Document 2).

In addition, a toner having excellent low-temperature fixability and a wide non-offset region by using two types of release agents has been proposed (see Patent Document 3).
On the other hand, regarding the compatibility between developability and fixability, there is also a proposal that the magnetic powder is not substantially exposed on the toner surface, and that both developability and fixability are achieved by using two types of release agents in combination. Yes (see Patent Documents 4 and 5). However, according to these patent documents, although the low-temperature fixability, storage stability, and developability are improved, there is no description regarding image unevenness.

Further, a toner capable of achieving heat fixing regardless of the material of the fixing device by controlling the storage viscoelasticity of the toner and the adhesive force between the aluminum substrate and a good image can be obtained (Patent Document 6). reference). Regarding this, there is no description about the image unevenness, and the effect on the image unevenness is insufficient, and there is room for improvement.

International Publication No. 1998/020396 International Publication No. 01/001200 JP 11-218960 A JP 2002-072540 A JP 2002-072546 A JP 2005-031339 A

  An object of the present invention is to provide a toner that can obtain a uniform image without image unevenness and has good fixability without any image unevenness.

As a result of intensive studies to solve the above problems, the present inventors have found that these problems can be solved by the following toner, and have reached the present invention.
That is, the present invention is a toner containing toner particles containing at least a binder resin, a colorant, and a release agent, and an inorganic fine powder, wherein the toner contains the release agent as the binder resin. relative to 100 parts by weight containing 20 parts by mass or less at least 5 parts by weight, adhesion force at the time of the toner was heated at 190 ° C. is, is at 50 N / ^{m 2} or more 500 N / ^{m 2} or less, the toner orthodichlorobenzene After dissolution, the soluble content of the toner obtained by shaking at a temperature of 25 ° C. for 24 hours was measured using size exclusion chromatography-online-multi-angle light scattering (SEC-MALLS). Weight average molecular weight (Mw) And the inertial square radius (Rw), the weight average molecular weight (Mw) is 50,000 to 200,000, and the inertial square radius (Rw) is the weight average molecular weight (Mw). The ratio of (Rw / Mw) is a toner which is characterized in that satisfy ^{1.0 × 10 -4 ≦ Rw / Mw} ≦ 4.0 × 10 -4, the relationship.

According to the present invention, it is possible to provide a toner having no image unevenness and capable of obtaining a uniform image and having a good fixability without an offset.

FIG. 3 is a schematic cross-sectional view illustrating an example of an image forming apparatus that can suitably use the toner of the present invention.

The toner of the present invention is a toner containing toner particles containing at least a binder resin, a colorant, and a release agent, and an inorganic fine powder, and the toner includes the release agent and the binder resin. relative to 100 parts by weight containing 20 parts by mass or less at least 5 parts by weight, adhesion force at the time of the toner was heated at 190 ° C. is, is at 50 N / ^{m 2} or more 500 N / ^{m 2} or less, the toner orthodichlorobenzene After dissolution, the soluble content of the toner obtained by shaking at a temperature of 25 ° C. for 24 hours was measured using size exclusion chromatography-online-multi-angle light scattering (SEC-MALLS). Weight average molecular weight (Mw) And the inertial square radius (Rw), the weight average molecular weight (Mw) is 50000 or more and 200000 or less, and the inertial square radius (Rw) is the weight average molecular weight (Mw). Against the ratio (Rw / Mw), characterized in that satisfy ^{1.0 × 10 -4 ≦ Rw / Mw} ≦ 4.0 × 10 -4, the relationship.

As a result of intensive studies by the present inventors, in the present invention, the toner contains a release agent in an amount of 5 parts by mass to 20 parts by mass with respect to 100 parts by mass of the binder resin.
1) Adhesive force when the toner is heated at 190 ° C. is 50 N / m ² or more and 500 N / m ² or less,
2) After dissolving the toner in orthodichlorobenzene, the soluble content of the toner obtained by shaking at a temperature of 25 ° C. for 24 hours was measured using size exclusion chromatography-online-multi-angle light scattering (SEC-MALLS). In the weight average molecular weight (Mw) and inertial square radius (Rw), the weight average molecular weight (Mw) is 50,000 to 200,000, and the ratio of the inertial square radius (Rw) to the weight average molecular weight (Mw) (Rw / Mw) Is 1.0 × 10 ⁻⁴ ≦
It has been found that by satisfying the relationship of Rw / Mw ≦ 4.0 × 10 ⁻⁴ , a uniform image without image unevenness can be obtained, and good fixability without offset can be obtained.

For this reason, the present inventors consider as follows.
Considering the behavior at the time of fixing, the toner receives heat and pressure in the fixing process, and is fixed on the paper by plasticizing and deforming. However, the paper as described above has irregularities derived from the fibers. For this reason, since the toner is extended at the time of fixing at the convex portion, the image density becomes low, while the image density tends to be high at the concave portion. Further, in the concave portion, sufficient pressure and heat are not easily transmitted during fixing, so that the toner is likely to be insufficiently melted and gloss is likely to be lowered. For this reason, the image density difference due to the minute unevenness of the paper and the gloss difference of the image cause unevenness of the image.

However, the toner of the present invention has a weight average molecular weight (Mw) of 50,000 or more and 200,000 or less when the orthodichlorobenzene soluble content of the toner is measured by size exclusion chromatography-online-multi-angle light scattering (SEC-MALLS). The ratio (Rw / Mw) of the inertial square radius (Rw) to the weight average molecular weight (Mw) is preferably 1.0 × 10 ⁻⁴ ≦ Rw / Mw ≦ 4.0 × 10. ^-4 (preferably 1.5 × 10 ⁻⁴ ≦ Rw / Mw ≦ 3.0 × 10 ⁻⁴ ), the toner is not extended even on the convex portion of the paper fiber, and the image density can be maintained. .
Here, the ratio (Rw / Mw) of the inertial square radius (Rw) to the weight average molecular weight (Mw) satisfies the relationship of 1.0 × 10 ⁻⁴ ≦ Rw / Mw ≦ 4.0 × 10 ⁻⁴ . This means that the binder resin of the toner is branched to some extent, and since the toner has a branched structure, it is difficult to extend the toner even when pressure is applied to the convex portion, and the image density can be maintained.
Moreover, the said effect is effectively exhibited as the said weight average molecular weight (Mw) is 50000-200000.
On the other hand, when the weight average molecular weight (Mw) is less than 50000, even if the binder resin has a certain degree of branched structure, the molecule itself becomes small, and the toner is extended at the convex portion. On the other hand, if the weight average molecular weight (Mw) is larger than 200000, the image density at the convex portion can be maintained, but the fixing property at the concave portion is deteriorated, which is not preferable.

Further, if the ratio (Rw / Mw) of the inertial square radius (Rw) to the weight average molecular weight (Mw) is larger than 4.0 × 10 ⁻⁴ , the toner is stretched by the convex portion, resulting in image unevenness. End up. Further, if (Rw / Mw) is less than 1.0 × 10 ⁻⁴ , the degree of branching of the binder resin is too large, and the fixing property in the concave portion is not preferable.
As described above, the weight average molecular weight (Mw) when the toner's orthodichlorobenzene-soluble component is measured by size exclusion chromatography-online-multi-angle light scattering (SEC-MALLS) is 50,000 to 200,000, and (Rw / Mw) is 1.0 × 10 ⁻⁴ or more and 4.0 × 10 ⁻⁴ or less, whereby density unevenness derived from paper fibers can be suppressed.

The toner of the present invention has an adhesive force of 50 N / m ² or more and 500 N / m ² or less (preferably 90 N / m ² or more and 250 N / m ² or less) when the toner is heated at 190 ° C. For example, it is plasticized and melted by being heated on contact with a roller or a film. Here, considering the pressure applied during fixing, the paper as described above has irregularities derived from the fibers. For this reason, while the convex part receives a high pressure, the pressure of the concave part is considered to be low.
When the pressure received from the fixing device at the convex portion is high, sufficient releasability can be obtained by oozing out a sufficient release agent from the toner. Further, since the convex portion has sufficient releasability and high pressure, it is considered that the gloss of the image becomes high. However, in the recess, the pressure received from the fixing device is lowered, and the amount of the release agent oozing out decreases. For this reason, the releasability from the fixing member becomes poor, and the toner easily adheres to the fixing member, and the image surface becomes rough and the gloss becomes low. The gloss difference of the image at such uneven portions becomes noise when the image is viewed, resulting in poor image uniformity and image unevenness.
For this reason, when the toner adhesive force is 500 N / m ² or less and the releasability is sufficiently high, the releasability between the toner and the fixing member is good even in the concave portion, and the gloss of the image is increased, so the image unevenness is improved. To do.
On the other hand, when the adhesion force of the toner is larger than 500 N / m ² , it is not preferable because the toner releasability is insufficient in the concave portion, and the gloss difference of the image is easily generated.
Further, when the toner adhesion is 50 N / m ² or less, the toner releasability is very good, and it can be said that a large amount of releasability exudes during fixing. In this state, the releasability also oozes out at the interface between the toner and the paper, and the anchoring force to the medium is inferior, or the melting / integrating of the toner particles is inhibited, resulting in an offset, which is not preferable.
Therefore, in the present invention, it is important that the adhesion force of the toner is 50 N / m ² or more and 500 N / m ² .
The adhesion force in the present invention is defined as a value when the toner is heated to 190 ° C., which is derived from the fact that the surface temperature of the fixing member is around 190 ° C.

The toner of the present invention contains a release agent in an amount of 5 parts by mass to 20 parts by mass, preferably 5 parts by mass to 18 parts by mass with respect to 100 parts by mass of the binder resin.
When the content of the release agent is 5 parts by mass or more and 20 parts by mass or less, plasticization of the toner is promoted. Further, in the present invention, the weight average molecular weight (Mw) molecular weight when the amount of orthodichlorobenzene soluble component of the toner is measured by size exclusion chromatography-online-multi-angle light scattering (SEC-MALLS) is 50,000 to 200,000. Since it is relatively small, the fixing property is improved by the synergistic effect of both. For this reason, the gloss in the recesses can be increased and offset can be prevented.
When the content of the release agent is less than 5 parts by mass, the above effect cannot be obtained and image unevenness easily occurs and offset is also undesirable. On the other hand, if the content of the release agent is more than 20 parts by mass, the fixability is improved, but the durability of the toner is inferior and the toner is liable to deteriorate during long-term use.

As described above, 1) the toner binder resin has an appropriate branching structure, so that there is no difference in image density in the concavo-convex portion, and 2) there is no difference in image gloss due to good toner releasability. ) Due to the synergistic effect of good fixability, there is no offset and a uniform image with no unevenness can be obtained.

As described above, in the present invention, the inertial square radius of the toner soluble in orthodichlorobenzene is measured by size exclusion chromatography-online-multi-angle light scattering (SEC-MALLS) for the following reason. It is as follows.
The molecular weight distribution measured by SEC is the molecular size and the intensity is its abundance. On the other hand, the light scattering intensity obtained with SEC-MALLS (by combining SEC and a multi-angle light scattering detector as a separation means, the absolute molecular weight and molecular size (inertial square radius) can be measured) is the molecular size. Increases strength. However, the presence of a peak due to the elution time in SEC-MALLS measurement means that a polymer having a molecular spread (molecular size) at the molecular weight exists with a number distribution.
In the conventional SEC method, when a molecule to be measured passes through a column, the molecule is subjected to a molecular sieving effect and eluted according to the molecular size, and the molecular weight is measured. In this case, a linear polymer and a branched polymer having the same molecular weight are eluted earlier because the former has a larger molecular size in the solution. Therefore, the molecular weight of the branched polymer measured by the SEC method is measured smaller than the true molecular weight.
On the other hand, in the light scattering method of the present invention, Rayleigh scattering of the measurement molecule was used.
By measuring the dependence of the incident angle of the light and the sample concentration on the intensity of the scattered light, and analyzing it by the Zimm method, the Berry method, etc., the true molecular weight in the molecular form of all linear polymers and branched polymers (
Absolute molecular weight) can be determined. (In the present invention, the absolute molecular weight was calculated by the Zim method by the SEC-MALLS measurement method (described later)). As a result, the molecular design of the toner can be performed precisely.
In the present invention, the above (Rw / Mw) can be adjusted as follows. As described above, (Rw / Mw) represents the degree of branching of the binder resin. In the present invention, it is essential that the binder resin has an appropriate degree of branching. For this reason, for example, when the toner particles used in the present invention are produced by a suspension polymerization method (described later), the polymerization conditions may be adjusted. Specifically, in order to make the binder resin take a branched structure, a means of causing a hydrogen abstraction reaction or the like during the polymerization of the binder resin and branching by this can be suitably exemplified.
In order to cause the hydrogen abstraction reaction during the polymerization, it can be achieved by means such as rapidly increasing the radical concentration during the polymerization. As these means, for example, a polymerization initiator having a lower half-life temperature of 10 ° C. or more, more preferably 15 ° C. or more, is added during the polymerization, or an oxidation-reduction reaction (redox reaction) at a higher polymerization temperature. And so on. Usually, the oxidation-reduction reaction has the merit that the polymerization temperature can be lowered and the polymerization can proceed under mild conditions, but the polymerization progresses vigorously by performing the oxidation-reduction reaction at a high temperature, and hydrogen abstraction occurs actively. It becomes like this.
In these means, it is possible to arbitrarily change the degree of branching of the resin by changing the timing for rapidly increasing the radical concentration. Specifically, it is preferable to perform an oxidation-reduction reaction when the conversion rate of the polymerizable monomer is 30% or more and 60% or less, or to add a polymerization initiator having a low half-life temperature.

On the other hand, the adhesion force of the toner can be adjusted by the degree of branching of the binder resin and the type and amount of the release agent. The adhesive force can be reduced by the seepage of the release agent as described above, but it is important that the binder resin is appropriately branched and has a certain degree of elasticity at the time of fixing.
This is because, even if the release agent oozes out, if the toner itself is not elastic, the toner is deformed too much by the pressure from the fixing device, and the toner adheres to the fixing member.

Here, it is preferable to use a release agent having a high releasability as the release agent, and more preferably, the release agent contains at least the release agent A and the release agent B. The total amount is particularly preferably 5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin.
Further, the solubility of the release agent A in the styrene-acrylic resin is 3 or less, and the solubility obtained by subtracting the solubility of the release agent A in the styrene-acrylic resin from the solubility of the release agent B in the styrene-acrylic resin. When the difference is 5 or more and 20 or less, the releasability and the fixing property are improved, and the image unevenness is further improved, which is very preferable.
For this reason, it contains a release agent A having a solubility in styrene-acrylic resin of 3 or less, and a release agent B having a solubility in styrene-acrylic resin of 5 or more and 20 or less higher than that of release agent A. By doing so, the release of the release agent B becomes very quick. This is considered to be caused by extruding the release agent B which does not dissolve in the binder resin and thus expands at the time of fixing and dissolves in the binder resin (that is, easily penetrates). Therefore, the releasability is very good.
Further, the fact that the release agent B is pushed out is very preferable because the toner is deformed at the same time, and the fixing property is good.
In the present invention, the solubility in the styrene-acrylic resin is an index representing the solubility of the toner in the binder resin.

As described above, the release agent A preferably has a solubility in styrene-acrylic resin of 3 or less. Therefore, the release agent A is preferably a tetrafunctional or hexafunctional ester wax.
The alcohol component of these ester waxes is preferably pentaerythritol or dipentaerythritol, and the carboxylic acid component is preferably a carboxylic acid having 16 to 26 carbon atoms, more preferably 18 to 24 carbon atoms. Specific examples of carboxylic acids having 16 to 26 carbon atoms include palmitic acid, stearic acid, oleic acid, vaccenic acid, linoleic acid, linolenic acid, elestearic acid, tuberculostearic acid, arachidic acid, arachidonic acid and behenic acid. , Lignoceric acid, nervonic acid, serotic acid and the like.

On the other hand, as a release agent other than the release agent A (including the release agent B), all known release agents can be used. Specifically, petroleum waxes and derivatives thereof such as paraffin wax, microcrystalline wax, petrolactam, montan wax and derivatives thereof, hydrocarbon waxes and derivatives thereof by Fischer-Tropsch method, polyolefin waxes and derivatives thereof typified by polyethylene Natural waxes such as carnauba wax and candelilla wax and their derivatives.
Here, the derivatives include oxides, block copolymers with vinyl monomers, and graft modified products. Furthermore, fatty acids such as higher aliphatic alcohols, stearic acid and palmitic acid and compounds thereof, acid amide waxes, ester waxes, ketones, hydrogenated castor oil and derivatives thereof, plant waxes, animal waxes and the like can also be used. The ester wax is preferably a monofunctional ester wax, a bifunctional ester wax, or a trifunctional ester wax. The endothermic peak top temperatures measured by a differential scanning calorimeter (DSC) of the release agent A and release agent B used in the present invention are preferably 50 ° C. or more and 90 ° C. or less. When the endothermic peak top temperature is 50 ° C. or higher and 90 ° C. or lower, the toner is easily plasticized at the time of fixing, and the fixing property is improved.

The release agent used for the toner of the present invention preferably contains at least the release agent A and the release agent B, but the release agent A is 5 mass% or more and 50 mass% or less of the total release agent amount. In addition, the release agent B is preferably 50% by mass or more and 95% by mass or less of the total amount of the release agent. When the amount of the release agent A is in the above range, it is easy to balance the releasability and the fixability, and the image unevenness and the offset are good.

The solubility of the release agent A and the release agent B in the styrene-acrylic resin depends on the endothermic peak top temperature, structure, and molecular weight of the release agent measured by a differential scanning calorimeter. There is a tendency. As an example, those with low endothermic peak top temperatures of release agents tend to have high solubility, and those with the same endothermic peak top temperature have high molecular weight, and those with a bulky structure have low solubility. There is a tendency.

The toner of the present invention preferably has an average circularity measured using a flow type particle image measuring device of 0.960 or more, and more preferably a mode circularity of 0.97 or more. When the average circularity of the toner is 0.960 or more, the shape of the toner is a sphere or a shape close to this, and it is easy to obtain a uniform triboelectric chargeability with excellent fluidity. Furthermore, since toner having a high average circularity has a uniform toner shape, it is considered that the heat transfer from the fixing device is uniform. For this reason, the fixability of the toner in the concave portion is improved and the gloss is improved. Therefore, it is preferable for improving image unevenness.

The weight average particle size (D4) of the toner of the present invention is preferably from 3.0 to 12.0 μm, more preferably from 4.0 to 10.0 μm. When the weight average particle diameter (D4) is 3.0 μm or more and 12.0 μm or less, good fluidity can be obtained and development can be performed faithfully to the latent image. For this reason, a good image excellent in dot reproducibility can be obtained.

In the toner of the present invention, it is preferable that the tetrahydrofuran (THF) insoluble content of the resin component of the toner is 15% by mass or more and 50% by mass or less based on the resin component.
When the tetrahydrofuran (THF) insoluble content is 15% by mass or more and 50% by mass or less, high-temperature offset is improved, durability is improved, and dot reproducibility and image unevenness hardly occur even in the latter half of the durability.
In the present invention, the tetrahydrofuran (THF) insoluble matter can be arbitrarily adjusted according to the amount, type and polymerization conditions of the crosslinking agent at the time of toner particle production.

The toner of the present invention preferably has a peak molecular weight (Mp) of 12,000 or more and 18,000 or less in the molecular weight distribution measured by gel permeation chromatography of the tetrahydrofuran (THF) soluble part of the toner.
When the peak molecular weight (Mp) is 12000 or more and 18000 or less, the plasticity / deformation of the toner at the time of fixing is promoted, and the low-temperature fixing property is improved. Further, since the fixing property at the concave portion is also good, offset is less likely to occur, which is more preferable. Further, even in the latter half of the endurance, it is possible to suppress a decrease in density and an increase in fog due to toner deterioration.

Examples of the binder resin used in the toner of the present invention include styrene such as polystyrene and polyvinyltoluene, and homopolymers thereof and styrene-propylene copolymers, styrene-vinyltoluene copolymers, and styrene-vinylnaphthalene copolymers. Polymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene -Methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl Ether copolymer, styrene Styrene copolymers such as vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer, polymethyl methacrylate, poly Butyl methacrylate, polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyester resin, polyamide resin, epoxy resin, and polyacrylic acid resin can be used. These can be used alone or in combination of two or more. Of these, styrene-acrylic resins are particularly preferred from the standpoints of development characteristics and fixing properties.

In the toner of the present invention, a charge control agent may be blended as necessary to improve charging characteristics. As the charge control agent, known ones can be used, but a charge control agent that has a high charging speed and can stably maintain a constant charge amount is particularly preferable. Furthermore, when the toner is produced using a polymerization method as described later, a charge control agent having a low polymerization inhibitory property and substantially free from a solubilized product in an aqueous dispersion medium is particularly preferable. Among the charge control agents, specific examples of negative charge control agents include metal compounds of aromatic carboxylic acids such as salicylic acid, alkyl salicylic acid, dialkyl salicylic acid, naphthoic acid, dicarboxylic acid, azo dyes or metal salts of azo pigments or Examples thereof include a metal complex, a polymer compound having a sulfonic acid or carboxylic acid group in the side chain, a boron compound, a urea compound, a silicon compound, and a calixarene. Examples of the positive charge control agent include a quaternary ammonium salt, a polymer compound having the quaternary ammonium salt in the side chain, a guanidine compound, a nigrosine compound, and an imidazole compound.
As a method for incorporating a charge control agent into the toner, a method of adding the charge control agent to the inside of the toner particles, and in the case of producing the toner by suspension polymerization, the charge control agent is contained in the polymerizable monomer composition before granulation. The method of adding is common. Also, during the polymerization by forming oil droplets in water, or after the polymerization, seed polymerization is performed by adding a polymerizable monomer in which the charge control agent is dissolved and suspended, and the toner surface is made uniform. It is also possible to cover. In the case where an organometallic compound is used as the charge control agent, it is also possible to introduce the compound by adding these compounds to the toner particles, applying a shear and mixing and stirring.
The amount of these charge control agents used is determined by the toner production method including the type of binder resin, the presence or absence of other additives, and the dispersion method, and is not uniquely limited. However, when it is internally added to the toner particles, it is preferably 0.1 parts by weight or more and 10.0 parts by weight or less, more preferably 0.1 parts by weight or more and 5.0 parts by weight or less with respect to 100 parts by weight of the binder resin. Used in a range. Further, when externally added to the toner particles, the amount is preferably 0.005 parts by mass or more and 1.000 parts by mass or less, more preferably 0.01 parts by mass or more and 0.30 parts by mass or less with respect to 100 parts by mass of the toner.

In the present invention, the toner particles contain a colorant that matches the target color. As the colorant used in the toner of the present invention, any of known organic pigments or dyes, carbon black, magnetic materials and the like can be used.
Specifically, copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, basic dye lake compounds, and the like can be used as cyan colorants. Specifically, C.I. I. Pigment blue 1, C.I. I. Pigment blue 7, C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 1, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 15: 4, C.I. I. Pigment blue 60, C.I. I. Pigment blue 62, C.I. I. And CI Pigment Blue 66.

As the magenta colorant, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds are used. Specifically, C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment violet 19, C.I. I. Pigment red 23, C.I. I. Pigment red 48: 2, C.I. I. Pigment red 48: 3, C.I. I. Pigment red 48: 4, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 81: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 144, C.I. I. Pigment red 146, C.I. I. Pigment red 166, C.I. I. Pigment red 169, C.I. I. Pigment red 177, C.I. I. Pigment red 184, C.I. I. Pigment red 185, C.I. I. Pigment red 202, C.I. I. Pigment red 206, C.I. I. Pigment red 220, C.I. I. Pigment red 221, C.I. I. And CI Pigment Red 254.

As the yellow colorant, compounds represented by condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and allylamide compounds are used. Specifically, 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 62, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 83, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 95, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 109, C.I. I. Pigment yellow 110, C.I. I. Pigment yellow 111, C.I. I. Pigment yellow 120, C.I. I. Pigment yellow 127, C.I. I. Pigment yellow 128, C.I. I. Pigment yellow 129, C.I. I. Pigment yellow 147, C.I. I. Pigment yellow 151, C.I. I. Pigment yellow 154, C.I. I. Pigment yellow 168, C.I. I. Pigment yellow 174, C.I. I. Pigment yellow 175, C.I. I. Pigment yellow 176, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 181, C.I. I. Pigment yellow 191, C.I. I. And CI Pigment Yellow 194.

These colorants can be used singly or in combination of two or more, and can also be used in a solid solution state. The colorant used in the toner of the present invention is appropriately selected from the viewpoints of hue angle, saturation, brightness, light resistance, OHP transparency, and dispersibility in toner particles. Moreover, the addition amount of the coloring agent is preferably 1.0 part by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the binder resin.
In addition, as the black colorant, a carbon black, a magnetic material, and a color adjusted to black using the yellow, magenta, and cyan colorants are used. When carbon black is used as the black colorant, the amount added is preferably 1.0 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the binder resin.

In addition, when the toner of the present invention is used as a magnetic toner, it is possible to use a magnetic material as a colorant. When a magnetic material is used as the black colorant, the magnetic material is preferably 20.0 parts by mass or more and 150.0 parts by mass or less with respect to 100 parts by mass of the binder resin. When the added amount of the magnetic material is less than 20.0 parts by mass, the fixability is improved, but the coloring power of the toner is poor and fogging is difficult to suppress. On the other hand, when the amount exceeds 150.0 parts by mass, the fixability is lowered and the holding force by the magnetic force of the toner carrier is increased and the developability tends to be lowered.

The content of the magnetic substance in the toner particles can be measured using a thermal analysis device manufactured by PerkinElmer, TGA7. The measuring method is as follows. The toner is heated from room temperature to 900 ° C. at a temperature rising rate of 25 ° C./min in a nitrogen atmosphere. The weight loss mass% between 100 ° C. and 750 ° C. is defined as the binder resin amount, and the remaining mass is approximately defined as the magnetic material amount.

In the present invention, when toner particles are produced using a polymerization method, it is necessary to pay attention to the polymerization inhibition property and water phase transfer property of the colorant. Therefore, the colorant should be subjected to surface modification, for example, a hydrophobic treatment with a substance that does not inhibit polymerization. In particular, since dyes and carbon black have many polymerization-inhibiting properties, care must be taken when using them. About carbon black, you may process with the substance which reacts with the surface functional group of carbon black, for example, polyorganosiloxane.

When a magnetic material is used for the toner of the present invention, the magnetic material is mainly composed of magnetic iron oxide such as triiron tetroxide or γ-iron oxide, and phosphorus, cobalt, nickel, copper, magnesium, manganese, Elements such as aluminum and silicon may be included. These magnetic materials preferably have a BET specific surface area of 2.0 m ² / g or more and 30.0 m ² / g or less, and 3.0 m ² / g or more and 28.0 m ² / g or less by a nitrogen adsorption method. Is more preferable.
The shape of the magnetic material includes a polyhedron, octahedron, hexahedron, sphere, needle shape, flake shape, etc., but a polyhedron, octahedron, hexahedron, sphere and the like having a small anisotropy can reduce the image density. It is preferable in terms of enhancement.
The magnetic material preferably has a volume average particle size of 0.10 μm or more and 0.40 μm or less. Generally, the smaller the particle size of the magnetic material, the higher the coloring power, but the magnetic material tends to aggregate and the uniform dispersibility of the magnetic material in the toner tends to be poor. In addition, when the volume average particle size is less than 0.10 μm, the magnetic substance itself becomes reddish black, so that an image with a conspicuous redness is apt to be generated particularly in a halftone image. On the other hand, when the volume average particle size is larger than 0.40 μm, the coloring power of the toner is insufficient, and uniform dispersion tends to be difficult in the suspension polymerization method (described later) which is a preferable method for producing the toner of the present invention. .
The volume average particle diameter of the magnetic material can be measured using a transmission electron microscope. Specifically, after sufficiently dispersing the toner particles to be observed in the epoxy resin, a cured product obtained by curing in an atmosphere at a temperature of 40 ° C. for 2 days is obtained. The obtained cured product is used as a flaky sample by a microtome, and the diameter of 100 magnetic particles in the field of view is measured with a transmission electron microscope (TEM) at a magnification of 10,000 to 40,000 times. Then, the volume average particle diameter is calculated based on the equivalent diameter of a circle equal to the projected area of the magnetic material. It is also possible to measure the particle size with an image analyzer.

The magnetic material used in the toner of the present invention can be produced, for example, by the following method. An aqueous solution containing ferrous hydroxide is prepared by adding an alkali such as sodium hydroxide in an amount equivalent to or greater than the iron component to the ferrous salt aqueous solution. Air was blown in while maintaining the pH of the prepared aqueous solution at 7.0 or higher, and ferrous hydroxide was oxidized while heating the aqueous solution to 70 ° C. or higher, and seed crystals serving as the core of the magnetic iron oxide particles were formed. First generate.
Next, an aqueous solution containing about 1 equivalent of ferrous sulfate is added to the slurry-like liquid containing seed crystals based on the amount of alkali added previously. The pH of the liquid is maintained at 5.0 or more and 10.0 or less, and the reaction of ferrous hydroxide is advanced while blowing air, thereby growing magnetic iron oxide particles with the seed crystal as a core. At this time, it is possible to control the shape and magnetic properties of the magnetic material by selecting an arbitrary pH, reaction temperature, and stirring conditions. As the oxidation reaction proceeds, the pH of the liquid shifts to the acidic side, but the pH of the liquid is preferably not less than 5.0. A magnetic material can be obtained by filtering, washing, and drying the magnetic material thus obtained by a conventional method.
In the present invention, when the toner particles are produced by a polymerization method, it is very preferable to subject the surface of the magnetic material to a hydrophobic treatment. When the hydrophobizing treatment is performed by a dry method, the hydrophobizing treatment is performed on the washed, filtered and dried magnetic material using a coupling agent. When the hydrophobization treatment is performed in a wet manner, after the oxidation reaction is completed, the dried material is redispersed, or after the oxidation reaction is completed, the iron oxide body obtained by washing and filtering is not dried and another aqueous medium is used. It is redispersed in and hydrophobized. Specifically, the hydrophobization treatment is performed by adding a coupling agent while sufficiently stirring the re-dispersed liquid to increase the temperature after hydrolysis, or adjusting the pH of the dispersion to an alkaline region after hydrolysis. Among these, from the viewpoint of carrying out a uniform hydrophobization treatment, it is preferable to carry out the hydrophobization treatment after completion of the oxidation reaction, by reslurry as it is without drying after filtration and washing.
To hydrophobize a magnetic material, that is, in order to treat the magnetic material with a coupling agent in an aqueous medium, first, sufficiently disperse the magnetic substance in the aqueous medium so as to have a primary particle size, and do not settle or aggregate. Stir with a stirring blade or the like. Next, an arbitrary amount of coupling agent is added to the above dispersion, and hydrophobized while hydrolyzing the coupling agent. At this time, it is sufficient to prevent aggregation while using a device such as a pin mill or a line mill while stirring. It is more preferable to perform the hydrophobizing treatment while dispersing.
Here, the aqueous medium is a medium containing water as a main component. Specific examples include water itself, water added with a small amount of surfactant, water added with a pH adjusting agent, and water added with an organic solvent. As the surfactant, nonionic surfactants such as polyvinyl alcohol are preferable. The addition amount of the surfactant is preferably 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of water. Examples of the pH adjusting agent include inorganic acids such as hydrochloric acid. Examples of the organic solvent include alcohols.

Examples of the coupling agent that can be used for the hydrophobic treatment of the magnetic substance include a silane coupling agent and a titanium coupling agent. More preferably used are silane coupling agents, which are represented by the general formula (1).
R _m SiY _n (1)
[Wherein, R represents an alkoxy group, m represents an integer of 1 to 3, Y represents a functional group such as an alkyl group, a vinyl group, an epoxy group, or a (meth) acryl group, and n represents 1 to 3] Indicates an integer. However, m + n = 4. ]
Examples of the silane coupling agent represented by the general formula (1) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, Vinyltriacetoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, dipheny Diethoxysilane, n-butyltrimethoxysilane, isobutyltrimethoxysilane, trimethylmethoxysilane, n-hexyltrimethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane, hydroxypropyl Examples include trimethoxysilane, n-hexadecyltrimethoxysilane, and n-octadecyltrimethoxysilane.
Among these, from the viewpoint of imparting high hydrophobicity to the magnetic material, it is preferable to use an alkyltrialkoxysilane coupling agent represented by the following general formula (2).
During _{C p H 2p + 1 -Si- (} OC q H 2q + 1) 3 (2) [ wherein, p represents an integer of from 2 to 20, q is an integer of 1 to 3. ]
When p in the above formula is smaller than 2, it is difficult to sufficiently impart hydrophobicity to the magnetic material. When p is larger than 20, hydrophobicity is sufficient, but the coalescence between the magnetic materials increases. It is not preferable. Furthermore, when q is larger than 3, the reactivity of the silane coupling agent is lowered and it becomes difficult to sufficiently perform hydrophobicity. Accordingly, in the formula, p represents an integer of 2 to 20 (more preferably, an integer of 3 to 15), and q represents an integer of 1 to 3 (more preferably, an integer of 1 or 2). It is preferable to use a coupling agent.
When using the said silane coupling agent, it is possible to process independently or to process in combination of several types. When using several types together, you may process separately with each coupling agent, and may process simultaneously.
The total amount of coupling agent used is preferably 0.5 to 3.0 parts by mass with respect to 100 parts by mass of the magnetic material, depending on the surface area of the magnetic material, the reactivity of the coupling agent, etc. It is important to adjust the amount of treatment agent.

In the present invention, other colorants may be used in addition to the magnetic substance. Examples of the colorant that can be used in combination include magnetic or nonmagnetic inorganic compounds in addition to the above-described known dyes and pigments. Specifically, ferromagnetic metal particles such as cobalt and nickel, or alloys obtained by adding chromium, manganese, copper, zinc, aluminum, rare earth elements and the like to these. Examples thereof include particles such as hematite, titanium black, nigrosine dye / pigment, carbon black, and phthalocyanine. These are also preferably used by treating the surface.

The glass transition temperature (Tg) of the toner of the present invention is preferably 40.0 ° C. or higher and 70.0 ° C. or lower. When the glass transition temperature is less than 40.0 ° C., the storage stability is lowered, and the toner is liable to deteriorate during long-term use. Therefore, considering the balance between fixability, storage stability, and developability, the glass transition temperature of the toner is preferably 40.0 ° C. or higher and 70.0 ° C. or lower.

The toner particles used in the present invention preferably have a core-shell structure in order to improve storage stability and developability. This is because by having a shell layer of high molecular weight, the surface property of the toner becomes uniform, the fluidity improves and the charging property becomes uniform.
Further, since the high molecular weight shell uniformly covers the surface layer of the toner particles, the low-melting-point substance does not easily leach out even during long-term storage, and the storage stability is improved.
For this reason, it is preferable to use an amorphous high molecular weight material for the shell layer, and from the viewpoint of charging stability, the acid value is preferably 5.0 mgKOH / g or more and 20.0 mgKOH / g or less.

As a specific method for forming the shell layer, the core particles are embedded with shell fine particles, or when the toner particles are produced in an aqueous medium, the shell particles are attached to the core particles and dried. Layers can be formed. In the dissolution suspension method and suspension polymerization method, the hydrophilicity of the high molecular weight material for the shell is used, and the high molecular weight material is unevenly distributed near the interface with water, that is, near the toner surface, to form a shell. Is possible. Furthermore, a shell can be formed by swelling a monomer on the surface of the core particle by a so-called seed polymerization method and polymerizing the monomer.

Examples of the high molecular weight body for the shell layer include styrene such as polystyrene and polyvinyltoluene and homopolymers thereof, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, Styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-methacrylic acid Acid methyl copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer Polymer, styrene-vinyl Styrene copolymers such as methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer, polymethyl methacrylate, polybutyl methacrylate , Polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyester resin, styrene-polyester copolymer, poly (meth) acrylate-polyester copolymer, polyamide resin, epoxy resin, polyacrylic acid resin, terpene resin, There are phenol resins and the like, and these can be used alone or in admixture of two or more. Moreover, you may introduce | transduce functional groups, such as an amino group, a carboxyl group, a hydroxyl group, a sulfonic acid group, a glycidyl group, a nitrile group, in these polymers.
As addition amount of these resin, it is preferable that it is 1.0 to 30.0 mass parts in total with respect to 100 mass parts of polymerizable monomers.
Among these resins, polyester is particularly preferable because the above effect is greatly exhibited. In the present invention, as the polyester resin used as necessary, a saturated polyester resin, an unsaturated polyester resin, or both can be appropriately selected and used.

The said polyester resin can use the normal thing comprised from an alcohol component and an acid component, and both components are illustrated below.
As alcohol components, ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexane Examples include diol, neopentyl glycol, 2-ethyl-1,3-hexanediol, cyclohexanedimethanol, butenediol, octenediol, cyclohexenedimethanol, hydrogenated bisphenol A, and bisphenol derivatives.
As the divalent carboxylic acid, benzene dicarboxylic acid such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride or its anhydride, alkyl dicarboxylic acid such as succinic acid, adipic acid, sebacic acid, azelaic acid or its anhydride, Furthermore, succinic acid substituted with an alkyl or alkenyl group having 6 to 18 carbon atoms or an anhydride thereof, unsaturated dicarboxylic acid such as fumaric acid, maleic acid, citraconic acid, itaconic acid or the anhydride thereof may be mentioned.
Furthermore, polyhydric alcohols such as glycerin, pentaerythritol, sorbit, sorbitan, and oxyalkylene ethers of novolak type phenol resins can be cited as polyhydric alcohol components. Trimellitic acid, pyromellitic acid, 1, 2, Examples include polyvalent carboxylic acids such as 3,4-butanetetracarboxylic acid, benzophenonetetracarboxylic acid, and anhydrides thereof.

Among the above-mentioned polyester resins, an alkylene oxide adduct of bisphenol A that is excellent in charging characteristics and environmental stability and balanced in other electrophotographic characteristics is preferably used. In the case of this compound, the average added mole number of alkylene oxide is preferably 2.0 mol or more and 10.0 mol or less from the viewpoint of fixability and toner durability.
The number average molecular weight (Mn) of the high molecular weight body forming the shell layer is preferably 2500 or more and 20000 or less. When the number average molecular weight (Mn) is less than 2500, developability, blocking resistance, and durability tend to decrease. On the other hand, when the number average molecular weight (Mn) exceeds 20000, the developability and durability are improved, but the low-temperature fixability is easily inhibited. The number average molecular weight (Mn) can be measured by gel permeation chromatography (GPC).

The toner of the present invention is a toner having toner particles containing at least a binder resin, a colorant, and a release agent, and an inorganic fine powder.
The toner particles can be produced by any known method.
First, when producing by a pulverization method, for example, a binder resin, a colorant, and components necessary for toner particles of a release agent and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill. Thereafter, the toner particles are melted and kneaded using a heat kneader such as a heating roll, a kneader, or an extruder to disperse or dissolve the toner particle material, and after cooling and solidification, pulverization, classification, and if necessary, a hydrophobic treatment is performed. Particles can be obtained. Either order of classification and hydrophobization treatment may be first. In the classification step, it is preferable to use a multi-division classifier in terms of production efficiency.
The pulverization step can be performed by a method using a known pulverizer such as a mechanical impact type or a jet type. Further, in the present invention, in order to obtain toner particles having a preferable circularity, it is preferable to further pulverize by applying heat or to perform an auxiliary mechanical impact treatment. Further, a hot water bath method in which finely pulverized (classified as necessary) toner particles are dispersed in hot water, a method of passing in a hot air stream, or the like may be used.
Examples of means for applying a mechanical impact force include a method using a mechanical impact type pulverizer such as a kryptron system manufactured by Kawasaki Heavy Industries, Ltd. or a turbo mill manufactured by Turbo Industry. In addition, like a mechano-fusion system manufactured by Hosokawa Micron Co., Ltd. or a hybridization system manufactured by Nara Machinery Co., Ltd., the toner particles are pressed against the inside of the casing by centrifugal force using blades that rotate at high speed, and forces such as compressive force and frictional force are applied. Thus, a method of applying a mechanical impact force to the toner particles can be mentioned.

The toner particles can be produced by a pulverization method as described above, but the toner particles obtained by this pulverization method are generally indefinite shapes. For this reason, in order to obtain an average circularity of 0.960 or more, which is a preferable physical property of the present invention, it is necessary to perform mechanical / thermal or some special treatment, resulting in poor productivity.
Therefore, in the present invention, the toner particles are preferably toner particles produced in an aqueous medium such as a dispersion polymerization method, an association aggregation method, a dissolution suspension method, a suspension polymerization method, or the like. The toner particles are particularly preferably toner particles produced by a suspension polymerization method from the viewpoint of easily satisfying the suitable physical properties of the present invention.

The suspension polymerization method includes a polymerizable monomer, a colorant and a release agent for constituting a binder resin, and a polymerization initiator, a crosslinking agent, a charge control agent, and other additives as necessary. A polymerizable monomer composition is obtained by uniformly dissolving or dispersing. Thereafter, the polymerizable monomer composition is dispersed in a continuous layer (for example, an aqueous phase) containing a dispersion stabilizer using a suitable stirrer, and simultaneously subjected to a polymerization reaction, whereby a toner having a desired particle size is obtained. Get particles. The toner particles obtained by this suspension polymerization method (hereinafter also referred to as “polymerized toner particles”) have individual toner particle shapes that are substantially spherical, so that by using this, the average circularity is 0.960 or more. It is easy to obtain a toner satisfying the physical property requirements suitable for the present invention. Furthermore, since the toner has a relatively uniform charge amount distribution, an improvement in image quality can be expected.

In the production of the polymerized toner particles, examples of the polymerizable monomer constituting the polymerizable monomer composition include the following.
Styrene monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene, methyl acrylate, ethyl acrylate, n-butyl acrylate, acrylic acid Acrylic esters such as isobutyl, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl methacrylate, methacrylic acid Ethyl, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethyl methacrylate Aminoethyl, methacrylic acid esters such as diethylaminoethyl methacrylate and other acrylonitrile, methacrylonitrile, and the like monomers acrylamide. These monomers can be used alone or in combination. Among the above-mentioned monomers, styrene or a styrene derivative is preferably used alone or mixed with other monomers from the viewpoint of developing characteristics and durability of the toner.

As the polymerization initiator used in the production of the toner particles by the polymerization method, those having a half-life of 0.5 hours or more and 30.0 hours or less during the polymerization reaction are preferable. Moreover, it is preferable that the addition amount of a polymerization initiator is 0.5 to 20.0 mass parts with respect to 100 mass parts of polymerizable monomers.
Specific examples of the polymerization initiator include 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1 -Carbonitrile), 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azo or diazo polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl Peroxide-based polymerization initiators such as peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, t-butylperoxy 2-ethylhexanoate, t-butylperoxypivalate Is mentioned.

When the toner particles are produced by a polymerization method, a cross-linking agent may be added. is there.
Here, as the crosslinking agent, compounds having two or more polymerizable double bonds are mainly used. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene, such as ethylene glycol diacrylate and ethylene glycol diacrylate. Carboxylic acid ester having two double bonds such as methacrylate, 1,3-butanediol dimethacrylate, etc., divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone, and three or more vinyl groups Compounds. These are used alone or as a mixture of two or more.

In the method for producing the toner particles by the polymerization method, the polymerizable monomer composition uniformly dissolved or dispersed by a disperser such as a homogenizer, a ball mill, or an ultrasonic disperser is dispersed as described above. Suspend in an aqueous medium containing a stabilizer. At this time, the particle size of the obtained toner particles becomes sharper by using a high-speed disperser such as a high-speed stirrer or an ultrasonic disperser to obtain a desired toner particle size at a stretch. Further, the polymerization initiator may be added at the same time when other additives are added to the polymerizable monomer, or may be mixed immediately before being suspended in the aqueous medium. Also, a polymerization initiator dissolved in a polymerizable monomer or solvent can be added immediately after granulation and before starting the polymerization reaction.
In addition, after granulation, it is sufficient to perform stirring to such an extent that the particle state is maintained and the floating / sedimentation of the particles is prevented using a normal stirrer.

Known surfactants, organic dispersants, and inorganic dispersants can be used as the dispersion stabilizer. In particular, inorganic dispersants are less likely to produce harmful ultrafine powders, and because of their steric hindrance, dispersion stability is obtained, so even if the reaction temperature is changed, stability is not easily lost, and washing is easy and does not adversely affect the toner. Therefore, it can be preferably used. Examples of such inorganic dispersants include tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, phosphate polyvalent metal salts such as hydroxyapatite, carbonates such as calcium carbonate and magnesium carbonate, calcium metasuccinate, calcium sulfate, Examples thereof include inorganic salts such as barium sulfate and inorganic compounds such as calcium hydroxide, magnesium hydroxide, and aluminum hydroxide. On the other hand, examples of the surfactant include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium stearate, and potassium stearate.
These inorganic dispersants are preferably used in an amount of 0.20 to 20.00 parts by mass with respect to 100 parts by mass of the polymerizable monomer. Moreover, the said dispersion stabilizer may be used independently and may use multiple types together. Furthermore, you may use together 0.0001 mass part or more and 0.1000 mass part or less surfactant with respect to 100 mass parts of polymerizable monomers.

When these inorganic dispersants are used, they may be used as they are, but in order to obtain finer particles, the inorganic dispersant particles can be generated and used in an aqueous medium. For example, in the case of tricalcium phosphate, a sodium phosphate aqueous solution and a calcium chloride aqueous solution can be mixed under high-speed stirring to produce water-insoluble calcium phosphate, which enables more uniform and fine dispersion. At the same time, water-soluble sodium chloride salt is produced as a by-product. However, if water-soluble salt is present in the aqueous medium, dissolution of the polymerizable monomer in water is suppressed, and ultrafine toner is generated by emulsion polymerization. This is more convenient.

In the step of polymerizing the polymerizable monomer, the polymerization temperature is set to 40 ° C or higher, and generally 50 ° C to 90 ° C.
After the polymerization of the polymerizable monomer is completed, the obtained polymer particles are filtered, washed and dried by a known method to obtain toner particles. The toner of the present invention can be obtained by mixing the toner particles with inorganic fine powder as will be described later and adhering them to the surface of the toner particles. It is also possible to insert a classification step in the manufacturing process (before mixing the inorganic fine powder) to cut coarse powder and fine powder contained in the toner particles.

The toner of the present invention contains an inorganic fine powder. The inorganic fine powder preferably has a number average primary particle size (D1) of 4 nm to 80 nm, more preferably 6 nm to 40 nm.
When the number average primary particle size (D1) of the inorganic fine powder is 4 nm or more and 80 nm or less, the toner has excellent fluidity, uniform chargeability can be obtained, and a uniform image can be obtained even in long-term use. I can get it.
In the present invention, the number average primary particle size (D1) of the inorganic fine powder is measured using a photograph of the toner magnified by a scanning electron microscope.

As the inorganic fine powder used in the present invention, fine powder such as silica, titanium oxide and alumina can be used. As the fine silica powder, for example, both a so-called dry method produced by vapor phase oxidation of silicon halide or dry silica called fumed silica, and so-called wet silica produced from water glass or the like can be used. is there. However, fewer silanol groups on the inner surface and the silica fine powder, also Na 2 _O, towards less dry silica of manufacture residues of SO ₃ ^2-like. In dry silica, it is also possible to obtain a composite fine powder of silica and other metal oxides by using other metal halogen compounds such as aluminum chloride and titanium chloride together with silicon halogen compounds in the production process, They are also included.
In the present invention, the addition amount of the inorganic fine powder is preferably 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the toner particles. The addition amount of the inorganic fine powder is preferably in the above range since the toner can be given good fluidity and the fixing property is not hindered.
The content of the inorganic fine powder can be quantified using a calibration curve prepared from a standard sample using fluorescent X-ray analysis.

In the present invention, it is preferable that the inorganic fine powder is a hydrophobized product because the environmental stability of the toner can be improved. Treatment agents used for hydrophobizing inorganic fine powder include silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, silane compounds, silane coupling agents, other organic silicon compounds, organic titanium compounds, and the like. May be used alone or in combination of two or more.
Among the above treatment agents, those treated with silicone oil are preferred, and those treated with silicone oil are more preferred at the same time as or after the hydrophobic treatment of the inorganic fine powder with the silane compound. As a method for treating such an inorganic fine powder, for example, as a first stage reaction, a silylation reaction is performed with a silane compound, silanol groups are eliminated by chemical bonds, and then a hydrophobic process is performed on the surface with silicone oil as a second stage reaction. A thin film can be formed.

In the toner of the present invention, other additives within a range that does not substantially adversely affect, for example, lubricant powder such as fluororesin powder, zinc stearate powder, polyvinylidene fluoride powder, cerium oxide powder, silicon carbide powder, A small amount of an abrasive such as strontium titanate powder, a fluidity-imparting agent such as titanium oxide powder or aluminum oxide powder, an anti-caking agent, or organic and inorganic fine particles having opposite polarity can also be used in small amounts. It is also possible to use the surface of these additives after hydrophobizing them.

Next, an example of an image forming apparatus that can suitably use the toner of the present invention will be specifically described with reference to FIG. In FIG. 1, reference numeral 100 denotes an electrostatic latent image carrier (photoconductor), which includes a contact charging member 117 (charging roller), a developing device 140 having a toner carrier 102, a transfer member 114 (transfer charging roller), A cleaner 116, a register roller 124, and the like are provided. The electrostatic latent image carrier 100 is charged to, for example, −600 V by the contact charging member 117 (applied voltages are, for example, an AC voltage of 1.85 kVpp and a DC voltage of −620 Vdc). Then, exposure is performed by irradiating the electrostatic latent image carrier 100 with laser light 123 by a laser generator 121 (latent image forming means, exposure device), and an electrostatic latent image corresponding to a target image is formed. The The electrostatic latent image on the electrostatic latent image carrier 100 is developed with a one-component toner by the developing device 140 to obtain a toner image. The obtained toner image is transferred onto the transfer material by the transfer member 114 in contact with the electrostatic latent image carrier via the transfer material. The transfer material on which the toner image is placed is conveyed to the fixing device 126 by the conveyance belt 125 or the like and fixed on the transfer material. In addition, the toner remaining on a part of the electrostatic latent image carrier is cleaned by a cleaner 116.

Hereinafter, methods for measuring physical properties of the toner of the present invention will be described.
(1) Measuring method of toner adhesion The toner adhesion is measured as follows using a plate tester. The plate used had a diameter of 75 mm, and a 3 mm thick silicone rubber layer was provided on the plate. Next, a solid image is formed on the OHP sheet so that the toner loading amount is 0.6 mg / cm ² , the toner image is heated and pressurized under the following conditions on the plate, and the stress when the plate is pulled up is increased. Find the integral value. The value obtained by dividing this by the area of the plate is defined as the adhesive force of the present invention.
<Plate heating / pressurizing conditions>
Plate temperature: 190 ° C
Plate pressing time: 50 ms
Plate pressing pressure: 30kgf
The plate temperature is equivalent to the fixing temperature of the evaluator (printer). The pressing time and pressure also correspond to the time / pressure when the paper passes through the contact portion between the pressure roller and the film when passing through the fixing device.

(2) Measurement method of weight average molecular weight Mw and inertial square radius Rw using size exclusion chromatography-online-multi-angle light scattering (SEC-MALLS) 0.03 g of toner is dispersed in 10 ml of orthodichlorobenzene (ODCB) and dissolved. Thereafter, the mixture is shaken with a shaker at a temperature of 25 ° C. for 24 hours and then filtered through a 0.2 μm filter to obtain a soluble portion of the toner as the filtrate. The filtrate is used as a sample.
[Analysis conditions]
Separation column: TOSOH (TSK GMHHR-H HT20; Tosoh Corporation) × 2 Column temperature: 135 ° C.
Mobile phase solvent: Orthodichlorobenzene Mobile phase flow rate: 1.0 ml / min.
Sample concentration: about 0.3%
Injection volume: 300 μl
Detector 1: Multi-angle light scattering detector (Wyatt DAWN EOS)
Detector 2: Differential refractive index detector (Shodex RI-71)

[Measurement theory]
(LS) = (dn / dc) ² × C × Mw × KLS (1)
(LS); Measurement voltage value of the detector (v)
(Dn / dc): Increment of refractive index per 1 g of sample (ml / g)
C: concentration (g / ml)
KLS: Coefficient of measurement voltage and scattering intensity (reduction Rayleigh ratio) (equipment constant)
In the present invention, the above (dn / dc) is 0.068 ml / g from the literature value of polystyrene.
In SEC-MALLS, it is separated by molecular size by the molecular sieve of the SEC column, and the weight average molecular weight Mw (absolute molecular weight) and C (concentration) are changed and eluted, so it is necessary to separately measure the concentration detector with MALLS There is. The signal intensity is converted into a concentration C to determine the weight average molecular weight Mw.
In the present invention, a differential refractive index detector (RI) is used as a concentration detector, and the signal intensity (RI) of the RI detector is converted into a concentration C and used.
(RI) = (dn / dc) × C × KRI (2)
KRI: Coefficient of measurement voltage and refractive index (RI constant, calibrated with polystyrene standard)
The molecular size (radius of inertia square) is calculated by Debye Plot.

(3) Measuring method of weight average particle diameter and particle size distribution of toner The weight average particle diameter (D4) of the toner is a precise particle size distribution measuring apparatus “Coulter Counter Multisizer 3 by a pore electric resistance method equipped with an aperture tube of 100 μm. (Registered trademark, manufactured by Beckman Coulter, Inc.) and the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) for measurement condition setting and measurement data analysis Measure with 25,000 measurement channels, analyze and analyze the measurement data.
As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.
Prior to measurement and analysis, the dedicated software is set as follows.
In the “Standard Measurement Method (SOM) Change Screen” of the dedicated software, set the total count in the control mode to 50000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter, Inc.) Set the value obtained using The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is checked.
In the “pulse to particle size conversion setting screen” of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.
The specific measurement method is as follows.
(1) About 200 ml of the electrolytic aqueous solution is put in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rotations / second. Then, dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the analysis software.
(2) About 30 ml of the electrolytic aqueous solution is put in a glass 100 ml flat bottom beaker, and "Contaminone N" (nonionic surfactant, anionic surfactant, organic builder pH 7 precision measurement is used as a dispersant therein. About 0.3 ml of a diluted solution obtained by diluting a 10% by weight aqueous solution of a neutral detergent for washing a vessel (made by Wako Pure Chemical Industries, Ltd.) 3 times with ion-exchanged water is added.
(3) Two oscillators with an oscillation frequency of 50 kHz are incorporated in a state where the phase is shifted by 180 degrees, and placed in a water tank of an ultrasonic disperser “Ultrasonic Dissipation System Tetora 150” (manufactured by Nikkiki Bios Co., Ltd.) having an electrical output of 120 W. A predetermined amount of ion-exchanged water is put, and about 2 ml of the above-mentioned Contaminone N is added to this water tank.
(4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.
(5) In a state where the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.
(6) To the round bottom beaker of (1) installed in the sample stand, the electrolyte solution of (5) in which the toner is dispersed is dropped using a pipette, and the measurement concentration is adjusted to about 5%. . The measurement is performed until the number of measured particles reaches 50,000.
(7) Analyze the measured data using the dedicated software attached to the device, and calculate the weight average particle size (D4. Analytical / volume statistics (arithmetic when graph / volume% is set with the dedicated software) The “average diameter” on the (average) screen is the weight average particle diameter (D4).

(4) Measuring method of average circularity and mode circularity of toner The average circularity and the mode circularity of toner are measured using a flow type particle image measuring device “FPIA-2100 type” (manufactured by Sysmex Corporation). Calculate using the following formula.

Here, the “particle projected area” is the area of the binarized toner particle image, and the “peripheral length of the particle projected image” is the length of the contour line obtained by connecting the edge points of the toner particle image. Define. The measurement uses the perimeter of the particle image when image processing is performed at an image processing resolution of 512 × 512 (pixels of 0.3 μm × 0.3 μm).
The circularity is an index indicating the degree of unevenness of the toner particles, and is 1.000 when the toner particles are perfectly spherical. The more complicated the surface shape, the smaller the circularity. The average circularity C, which means the average value of the circularity frequency distribution, is calculated from the following equation, where ci is the circularity (center value) at the dividing point i of the particle size distribution and m is the number of measured particles.

The mode circularity is a circularity value having the highest frequency in the circularity frequency distribution. In addition, “FPIA-2100” used for the measurement described above calculates the circularity of each particle and then calculates the average circularity and the circularity standard deviation. .000 is divided into equally divided classes every 0.010, and the average circularity and circularity standard deviation are calculated using the center value of the dividing points and the number of measured particles.
The measurement procedure is as follows. A dispersion is prepared by dispersing 5 mg of toner in 10 ml of water in which 0.1 mg of a surfactant is dissolved, and the dispersion is irradiated with ultrasonic waves (20 kHz, 50 W) for 5 minutes, and the concentration of the dispersion is 5000 to 20,000. Pieces / μl of dispersion are obtained. The obtained dispersion is measured with the above apparatus, and the average circularity of a particle group having a circle-equivalent diameter of 3 μm or more is determined.
In this measurement, the reason for measuring the circularity only for the particle group having an equivalent circle diameter of 3 μm or more is as follows. The group of particles having an equivalent circle diameter of less than 3 μm includes a group of external additives that exist independently from the toner particles. The influence of these external additives is eliminated, and the toner particles are more accurately circular. This is to obtain the degree. In order to suppress variation in circularity, the installation environment of the apparatus is controlled to 23 ° C. ± 0.5 ° C. so that the in-machine temperature of the flow type particle image analyzer FPIA-2100 is 26 to 27 ° C. Further, automatic focus adjustment is performed using 2 μm latex particles at regular intervals, preferably every 2 hours.
Further, the “FPIA-2100” is different from the “FPIA-1000” used for calculating the shape of the conventional toner in the following points. First, the magnification of the processed particle image is improved, and the accuracy of the toner shape measurement is improved by improving the processing resolution of the captured image (256 × 256 → 512 × 512). As a result, the device achieves a more reliable supplement of fine particles. Therefore, when it is necessary to measure the shape more accurately as in the present invention, the FPIA-2100 that can obtain information on the shape more accurately is more useful.

(5) Measuring method of insoluble content of tetrahydrofuran (THF) 1 g of toner is precisely weighed and charged on a cylindrical filter paper, and extracted with 200 ml of THF for 20 hours with Soxhlet. Thereafter, the cylindrical filter paper is taken out and dried in a vacuum at 40 ° C. for 20 hours to measure the residue mass, and the tetrahydrofuran (THF) insoluble content of the resin component of the toner is calculated from the following formula. The resin component of the toner is a component obtained by removing the magnetic powder, the charge control agent, the release agent component, the external additive, and the pigment from the toner. At the time of measuring the above THF-insoluble matter, the THF-insoluble matter based on the resin component is calculated in consideration of whether these contents are soluble or insoluble in THF.
THF insoluble content (%) = (W2-W3) / (W1-W3-W4) × 100
W1: Mass of magnetic toner
W2: Residual mass
W3: Mass of components insoluble in THF other than the resin component of the magnetic toner
W4: Mass of components soluble in THF other than the resin component of the magnetic toner

(6) Method of measuring peak molecular weight (Mp) of tetrahydrofuran (THF) soluble part such as toner The molecular weight distribution of THF soluble part of toner or resin is determined by gel permeation chromatography (GPC) as follows. taking measurement.
First, the toner or resin is dissolved in tetrahydrofuran (THF) at room temperature for 24 hours. The obtained solution is filtered through a solvent-resistant membrane filter “Maescho Disc” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is about 0.8% by mass. Using this sample solution, measurement is performed under the following conditions.
Apparatus: HLC8120 GPC (detector: RI) (manufactured by Tosoh Corporation)
Column: Seven series of Shodex KF-801, 802, 803, 804, 805, 806, 807 (manufactured by Showa Denko KK)
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 ml / min
Oven temperature: 40.0 ° C
Sample injection volume: 0.10 ml
In calculating the molecular weight of the sample, standard polystyrene resin (for example, trade name “TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F— 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation) are used.

(7) Method for measuring solubility of release agent in styrene-acrylic resin The solubility of the release agent in styrene-acrylic resin is measured as follows.
Styrene-acrylic resin (glass transition temperature (Tg) = 54.0 ° C., number average molecular weight (Mn) = 20000): 0.10 g
Release agent: 0.01 g
The above is mixed in an agate mortar and set in a differential scanning calorimeter (DSC).
Next, DSC measurement is performed according to the following sequence, and the endothermic peak heat amount of the second cycle is ΔH1, and the endothermic peak heat amount of the fourth cycle is ΔH2, and the solubility is obtained by the following equation.
Solubility = (1−ΔH1 / ΔH2) × 100
<Sequence>
1st cycle:-Hold at 30 ° C for 1 minute
・ Raise the temperature to 60 ° C at 2 ° C / min. Hold for 10 minutes after temperature rise
・ Temperature drop to 30 ° C at 10 ° C / min.
Second cycle:-Hold at 30 ° C for 1 minute
・ Raise the temperature to 120 ° C at 10 ° C / min. Hold for 10 minutes after temperature rise
・ Temperature drop to 30 ° C at 10 ° C / min.
3rd cycle:-Hold at 30 ° C for 1 minute
・ Raise the temperature to 60 ° C at 2 ° C / min. Hold for 10 minutes after temperature rise
・ Temperature drop to 30 ° C at 10 ° C / min.
4th cycle:-Hold at 30 ° C for 1 minute
・ Raise the temperature to 120 ° C at 10 ° C / min. Hold for 10 minutes after temperature rise
・ Temperature drop to 30 ° C at 10 ° C / min.
The DSC measurement is performed as follows.
DSC uses, for example, “Q1000” (manufactured by TA Instruments) to ASTM
Measured according to D3418-82. The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium. Specifically, about 10 mg of toner is precisely weighed and placed in an aluminum pan, and an empty aluminum pan is used as a reference, and measurement is performed in the above sequence.

Hereinafter, the present invention will be described more specifically with reference to production examples and examples, but these do not limit the present invention in any way. In addition, all the parts in the following mixing | blending show a mass part.

<Manufacture of magnetic body 1>
During an aqueous ferrous sulfate solution, 1.10 eq of sodium hydroxide solution from 1.00 relative to iron element, the amount of _P 2 _{O 5} to an iron element to be 0.15% by mass in terms of phosphorus, the iron element On the other hand, SiO ₂ in an amount of 0.50% by mass in terms of silicon element was mixed to prepare an aqueous solution containing ferrous hydroxide. The pH of the aqueous solution was 8.0, and an oxidation reaction was performed at 85 ° C. while blowing air to prepare a slurry liquid having seed crystals.
Subsequently, after adding ferrous sulfate aqueous solution so that it may become 0.90 to 1.20 equivalent with respect to the original alkali amount (sodium component of caustic soda) to this slurry liquid, the slurry liquid is maintained at pH 7.6, The oxidation reaction was promoted while blowing air to obtain a slurry liquid containing magnetic iron oxide. After filtration and washing, the water-containing slurry was once taken out. At this time, a small amount of water-containing sample was collected and the water content was measured. Next, this water-containing sample is put into another aqueous medium without being dried, stirred and redispersed with a pin mill while circulating the slurry, and the pH of the redispersed liquid is adjusted to about 4.8. Then, 1.6 parts by mass of n-hexyltrimethoxysilane coupling agent with respect to 100 parts by mass of magnetic iron oxide (the amount of magnetic iron oxide was calculated by subtracting the water content from the water-containing sample) was added with stirring. Hydrolysis was performed. Thereafter, the mixture was sufficiently stirred, and the pH of the dispersion was adjusted to 8.6 to perform a hydrophobic treatment. The produced hydrophobic magnetic material is filtered with a filter press, washed with a large amount of water, dried at 100 ° C. for 15 minutes, and then at 90 ° C. for 30 minutes. 0.21 μm magnetic body 1 was obtained.

<Manufacture of magnetic body 2>
During an aqueous ferrous sulfate solution, 1.10 eq of sodium hydroxide solution from 1.00 relative to iron element, the amount of _P 2 _{O 5} to an iron element to be 0.15% by mass in terms of phosphorus, the iron element On the other hand, SiO ₂ in an amount of 0.50% by mass in terms of silicon element was mixed to prepare an aqueous solution containing ferrous hydroxide. The pH of the aqueous solution was 8.0, and an oxidation reaction was performed at 85 ° C. while blowing air to prepare a slurry liquid having seed crystals.
Subsequently, after adding ferrous sulfate aqueous solution so that it may become 0.90 to 1.20 equivalent with respect to the original alkali amount (sodium component of caustic soda) to this slurry liquid, the slurry liquid is maintained at pH 7.6, The oxidation reaction was promoted while blowing air to obtain a slurry liquid containing magnetic iron oxide. After filtration and washing, the obtained particles were crushed to obtain a magnetic body 2 having a volume average particle diameter of 0.21 μm.

<Manufacture of toner 1>
After 450 parts by mass of 0.1 M Na ₃ PO ₄ aqueous solution was added to 720 parts by mass of ion-exchanged water and heated to 60 ° C., 67.7 parts by mass of 1.0 M CaCl ₂ aqueous solution was added to stabilize the dispersion. An aqueous medium containing the agent was obtained.
-Styrene 74.00 parts by mass-n-butyl acrylate 26.00 parts by mass-Divinylbenzene 0.52 parts by mass-Iron complex of monoazo dye (T-77: manufactured by Hodogaya Chemical Co., Ltd.) 1.50 parts by mass-Magnetic substance 1 90.0 parts by mass / saturated polyester resin 5.0 parts by mass (saturated polyester resin obtained by condensation reaction of bisphenol A ethylene oxide adduct (average addition number = 2 mol) and terephthalic acid; number average molecular weight (Mn) Is 5000, acid value is 12 mgKOH / g, glass transition temperature (Tg) is 68 ° C)
The above formulation was uniformly dispersed and mixed using an attritor (Mitsui Miike Chemical Co., Ltd.) to obtain a monomer composition. This monomer composition was heated to 60 ° C., and 12.0 parts by mass of Fischer-Tropsch wax (hereinafter abbreviated as FT-WAX; physical properties are shown in Table 1), dipentaerythritol stearic acid 3.0 parts by mass of an ester (hereinafter abbreviated as DP18; physical properties are shown in Table 1) were added, mixed and dissolved, and then 7.0 parts by mass of dilauroyl peroxide was dissolved as a polymerization initiator.
The monomer composition was charged into the aqueous medium, and granulated by stirring at 12,000 rpm for 10 minutes in a TK homomixer (Special Machine Industries Co., Ltd.) in an N ₂ atmosphere at 60 ° C. Thereafter, the mixture was reacted at 74 ° C. while stirring with a paddle stirring blade. When the polymerization conversion rate reached 50%, 2.0 parts by mass of sodium ascorbate was added, and the mixture was further reacted for 3 hours.
After completion of the reaction, the suspension was cooled, washed with hydrochloric acid, filtered and dried to obtain toner particles 1.
100 parts by mass of toner particles 1 and 1.0 part by mass of hydrophobic silica having a BET value of 120 m ² / g (silica having a number average primary particle size of 12 nm treated with hexamethyldisilazane and then with silicone oil) Were mixed with a Henschel mixer to obtain toner 1. Table 2 shows the physical properties of Toner 1.

<Manufacture of toner 2>
After 450 parts by mass of 0.1 M Na ₃ PO ₄ aqueous solution was added to 720 parts by mass of ion-exchanged water and heated to 60 ° C., 67.7 parts by mass of 1.0 M CaCl ₂ aqueous solution was added to stabilize the dispersion. An aqueous medium containing the agent was obtained.
-Styrene 74.00 parts by mass-n-butyl acrylate 26.00 parts by mass-Divinylbenzene 0.52 parts by mass-Iron complex of monoazo dye (T-77: manufactured by Hodogaya Chemical Co., Ltd.) 1.50 parts by mass-Magnetic substance 1 90.0 parts by mass / saturated polyester resin 5.0 parts by mass (saturated polyester resin obtained by condensation reaction of bisphenol A ethylene oxide adduct (average addition number = 2 mol) and terephthalic acid; number average molecular weight (Mn) Is 5000, acid value is 12 mgKOH / g, glass transition temperature (Tg) is 68 ° C)
The above formulation was uniformly dispersed and mixed using an attritor (Mitsui Miike Chemical Co., Ltd.) to obtain a monomer composition. This monomer composition was heated to 60 ° C. T. T. 12.0 parts by mass of WAX and 3.0 parts by mass of DP18 were added and mixed, and after dissolution, 7.0 parts by mass of an azo initiator: V60 (manufactured by Wako Chemical Co., Ltd.) was dissolved as a polymerization initiator.
The monomer composition was charged into the aqueous medium, and granulated by stirring at 12,000 rpm for 10 minutes in a TK homomixer (Special Machine Industries Co., Ltd.) in an N ₂ atmosphere at 60 ° C. Thereafter, the mixture was reacted at 74 ° C. while stirring with a paddle stirring blade. When the polymerization conversion rate reached 50%, 2.0 parts by mass of t-butylperoxyneoheptanoate was added, and the mixture was further reacted for 3 hours. After completion of the reaction, the suspension was cooled, washed with hydrochloric acid, filtered and dried to obtain toner particles 2.
Hydrophobic silica having 100 parts by mass of this toner particle 2 and a BET value of 120 m ² / g (silica having a number average primary particle size of 12 nm treated with hexamethyldisilazane and then treated with silicone oil) 1.0 part by mass Were mixed with a Henschel mixer to obtain toner 2. Table 2 shows the physical properties of Toner 2.

<Manufacture of toner 3>
In the production of the toner 1, F.I. T. T. Instead of WAX, 12.0 parts by mass of dibehenyl sebacate (hereinafter abbreviated as SE22; physical properties are shown in Table 1) was used, and instead of DP18, behenic acid ester of dipentaerythritol (hereinafter abbreviated as DP22. Physical properties are tabulated). 1) was 3.0 parts by mass. Further, the same procedure as in the production of the toner 1 was performed except that the amount of dilauroyl peroxide added was 8.0 parts by mass, and 2.0 parts by mass of sodium ascorbate was added when the polymerization conversion reached 60%. Toner 3 was obtained. Table 2 shows the physical properties of Toner 3.

<Manufacture of toner 4>
In the production of the toner 1, F.I. T. T. 10.0 parts by mass of carnauba wax (physical properties are shown in Table 1) was used instead of WAX, and DP18 was 5.0 parts by mass. Further, the amount of dilauroyl peroxide added was 5.0 parts by mass, and the same procedure as in the production of the toner 1 except that 1.5 parts by mass of sodium ascorbate was added when the polymerization conversion reached 30%. Toner 4 was obtained. Table 2 shows the physical properties of Toner 4.

<Manufacture of toner 5>
A toner 5 was obtained in the same manner as in the production of the toner 1 except that dipentaerythritol palmitate (hereinafter abbreviated as DP16; physical properties are shown in Table 1) was used instead of DP18 in the production of the toner 1. Table 2 shows the physical properties of Toner 5.

<Manufacture of toner 6>
In the production of toner 1, F.I. T. T. Toner 6 was obtained in the same manner as in production of toner 1 except that distearyl sebacate (hereinafter abbreviated as SE18; physical properties are shown in Table 1) was used instead of WAX. Table 2 shows the physical properties of Toner 6.

<Manufacture of toner 7>
In the production of the toner 1, the amount of DP18 added is 15.0 parts by mass. T. T. A toner 7 was obtained in the same manner as in the production of the toner 1 except that WAX was not used. Table 2 shows the physical properties of Toner 7.

<Manufacture of toner 8>
In the production of Toner 3, except that dilauroyl peroxide was added in an amount of 9.0 parts by mass and 3.0 parts by mass of sodium ascorbate was added when the polymerization conversion reached 60%. In the same manner as described above, toner 8 was obtained. Table 2 shows the physical properties of Toner 8.

<Manufacture of toner 9>
In the production of Toner 4, the amount of dilauroyl peroxide added was 5.5 parts by mass, and the production of Toner 4 was performed except that 0.5 parts by mass of sodium ascorbate was added when the polymerization conversion reached 40%. In the same manner as described above, a toner 9 was obtained. Table 2 shows the physical properties of Toner 9.

<Manufacture of Toner 10>
In the production of Toner 3, the amount of dilauroyl peroxide added was 10.0 parts by mass, and the production of Toner 3 was performed except that 3.0 parts by mass of sodium ascorbate was added when the polymerization conversion reached 60%. In the same manner, Toner 10 was obtained. Table 2 shows the physical properties of Toner 10.

<Manufacture of toner 11>
In the production of Toner 4, the amount of dilauroyl peroxide added was 5.0 parts by mass, and the toner 4 was produced except that 0.5 parts by mass of sodium ascorbate was added when the polymerization conversion reached 30%. In the same manner as described above, toner 11 was obtained. Table 2 shows the physical properties of Toner 11.

<Manufacture of toner 12>
In the production of the toner 10, 3.0 parts by mass of DP22 is 2.0 parts by mass of DP18, and 12.0 parts by mass of SE22 is 3.0 parts by mass of F.I. T. T. A toner 12 was obtained in the same manner as in the production of the toner 10 except that it was changed to WAX. Table 2 shows the physical properties of Toner 12.

<Manufacture of toner 13>
In the production of the toner 11, DP18 is 10.0 parts by mass, and carnauba wax 10.0 parts by mass is F.S. A toner 13 was obtained in the same manner as in the production of the toner 11 except that the amount was changed to 10.0 parts by mass of T-WAX. Table 2 shows the physical properties of Toner 13.

<Manufacture of toner 14>
(Preparation of resin fine particle dispersion)
Styrene 306 parts by mass n-butyl acrylate 94 parts by mass Divinylbenzene 3.6 parts by mass The above components were mixed and dissolved to prepare a solution.
A solution prepared by dissolving 4 parts by mass of an anionic surfactant in 570 parts by mass of ion-exchanged water was added to the prepared solution, emulsified and stirred, and heated to 74 ° C. 25.0 parts by mass of dilauroyl peroxide was added thereto, and 6.0 parts by mass of sodium ascorbate was added when the polymerization conversion reached 40%. Thereafter, the mixture was reacted for 5 hours to obtain a resin particle dispersion 1. The center particle diameter of the resin fine particles in the resin particle dispersion 1 was 260 nm.

(Preparation of magnetic dispersion)
Magnetic body 1 150 parts by weight Nonionic surfactant 10 parts by weight Ion-exchanged water 400 parts by weight The above components were mixed and dissolved, and dispersed by a homogenizer for 30 minutes to obtain a magnetic body dispersion 1.

(Preparation of release agent dispersion)
DP22 10 parts by weight SE22 40 parts by weight Cationic surfactant 5 parts by weight ion-exchanged water 200 parts by weight The above components are subjected to a dispersion treatment with a pressure discharge type homogenizer, and a release agent containing release agent particles having a center diameter of 0.16 μm An agent dispersion 1 was obtained.

(Manufacture of toner)
Resin fine particle dispersion 1 200 parts by weight Magnetic substance dispersion 1 283 parts by weight Release agent dispersion 1 64 parts by weight Polyaluminum chloride 1.23 parts by weight After thoroughly mixing and dispersing the above components with a homogenizer, stirring Heated to 58 ° C. Then, after hold | maintaining at 58 degreeC for 60 minute (s), 30 mass parts of resin fine particle dispersion 1 was further added and stirred.
Thereafter, the pH in the system was adjusted to 7.0 with a 0.5 mol / l aqueous sodium hydroxide solution, and then heated to 90 ° C. while stirring was continued, and stirred for 2 hours. Thereafter, the pH was lowered to 4.0 and held for 6 hours. After completion of the reaction, the mixture was cooled, filtered and sufficiently washed with ion exchange water, and then filtered, washed and dried to obtain magnetic particles. 100 parts by mass of the obtained magnetic particles and 1.0 part by mass of silica used in the production of the toner 1 were mixed with a Henschel mixer to obtain a toner 14 having a weight average particle diameter (D4) of 6.7 μm. Table 2 shows the physical properties of Toner 14.

<Manufacture of toner 15>
In the production of toner 14, toner 15 was obtained in the same manner as in the production of toner 14 except that the stirring at 90 ° C. for 2 hours was changed to the stirring at 80 ° C. for 1 hour. Table 2 shows the physical properties of Toner 15.

<Manufacture of Toner 16>
Toner 16 was obtained in the same manner as toner 15 except that DP22 was changed to DP18 and SE22 was changed to SE18. Table 2 shows the physical properties of Toner 16.

<Manufacture of toner 17>
In the production of the toner 12, DP18 is 3.0 parts by mass, F.I. T. T. A toner 17 was obtained in the same manner as in the production of the toner 12 except that -WAX was changed to 1.0 part by mass. Table 2 shows the physical properties of Toner 17.

<Manufacture of Toner 18>
In the production of the toner 13, F.I. T. T. A toner 18 was obtained in the same manner as in the production of the toner 13 except that -WAX was changed to 11.0 parts by mass. Table 2 shows the physical properties of Toner 18.

<Manufacture of Toner 19>
In the production of the toner 12, DP18 is added in an amount of 1.0 part by mass; T. T. -Toner 17 was obtained in the same manner as in the production of toner 12 except that WAX was changed to 4.0 parts by mass. Table 2 shows the physical properties of Toner 17.

<Manufacture of toner 20>
In the production of the toner 13, 15.0 parts by mass of DP18, F.I. T. T. A toner 20 was obtained in the same manner as in the production of the toner 13 except that -WAX was changed to 5.0 parts by mass. Table 2 shows the physical properties of Toner 20.

<Manufacture of toner 21>
In the production of the toner 10, the addition of dilauroyl peroxide was 11.0 parts by mass, and the toner 10 was produced except that 4.0 parts by mass of sodium ascorbate was added when the polymerization conversion reached 60%. In the same manner as described above, toner 21 was obtained. Table 2 shows the physical properties of Toner 21.

<Manufacture of toner 22>
In the production of the toner 11, the production of the toner 11 is performed except that the amount of dilauroyl peroxide added is 4.0 parts by mass and 0.5 parts by mass of sodium ascorbate is added when the polymerization conversion rate reaches 30%. In the same manner as described above, toner 11 was obtained. Table 2 shows the physical properties of Toner 11.

<Manufacture of toner 23>
In the production of the toner 14, the toner 23 was obtained in the same manner as in the production of the toner 14 except that 10 parts by mass of DP22 was changed to 50 parts by mass of polyethylene wax (physical properties are shown in Table 1) and SE22 was not used. Table 2 shows the physical properties of Toner 23.

<Manufacture of Toner 24>
In the production of the toner 14, the toner 24 was obtained in the same manner as in the production of the toner 14 except that 10 parts by mass of DP22 was changed to 50 parts by mass of paraffin wax (physical properties are shown in Table 1) and SE22 was not used. Table 2 shows the physical properties of Toner 24.

<Example 1>
Using an LBP3410 (manufactured by Canon) as an image forming apparatus, using toner 1 and printing 6000 sheets of horizontal lines with a printing rate of 2% in intermittent mode in a normal temperature and humidity environment (23 ° C./60% RH) A test was conducted. As the recording medium, FRB (grade) 75 g / m ² paper was used. As a result, the image density was high before and after the durability test, and a uniform image free from fogging on non-image areas and image unevenness could be obtained. In addition, no offset occurred during durability. The evaluation results are shown in Table 3.
Further, a fixing test (fixing temperature) was performed under the following conditions.
As media, FRB (grade) 90 g / m ² paper was used, and the development bias was set so that the image density of the halftone image was 0.80 to 0.85. Next, the fixing device was cooled to room temperature, the heater temperature of the fixing device was set (hereinafter referred to as a fixing temperature), and after passing power, the image was passed through and fixed. Thereafter, the fixed image was rubbed 10 times with a Silbon paper applied with a weight of 50 g / cm ² , and the temperature at which the density reduction rate of the fixed image after the rub was 15% was determined as the fixing start temperature. As a result, the fixing temperature was as low as 185 ° C. The evaluation results are shown in Table 3.

The evaluation methods for each evaluation performed in the examples and comparative examples of the present invention and the criteria for the evaluation will be described below.
<Image density>
As for the image density, a solid image portion was formed at the initial stage and after the 6000-sheet printing test, and the density of this solid image was measured with a Macbeth reflection densitometer (manufactured by Macbeth).

<Fog>
A white image was output at the initial stage and after the 6000 sheet printing test, and the reflectance was measured using a REFECTMETER MODEL TC-6DS manufactured by Tokyo Denshoku. On the other hand, the reflectance of the transfer paper (standard paper) before white image formation was measured in the same manner. A green filter was used as the filter. The fog was calculated from the reflectance before and after the white image output using the following formula.
Fog (reflectance) (%) = reflectance of standard paper (%)-reflectance of white image sample (%)
The determination criteria for fogging are as follows.
A: Very good (less than 1.5%)
B: Good (1.5% or more and less than 2.5% or less)
C: Normal (2.5% or more and less than 4.0% or less)
D: Poor (4% or more)

<Image unevenness>
Image unevenness was evaluated by visual judgment according to the following criteria.
A: Image unevenness does not occur, uniform image B: Although image unevenness is slightly generated, sufficient level C: Image unevenness is generated, but level D has no practical problem. Occurring and undesirable level

<Offset>
The offset was evaluated visually according to the following criteria.
A: No offset has occurred B: Some offset has occurred through endurance, but sufficient level C: Offset has occurred through endurance, but there is no practical problem D: Offset has occurred through endurance , Unfavorable level

<Examples 2 to 16>
An image formation test was conducted in the same manner as in Example 1 except that toners 2 to 16 were used. As a result, an image with a level that is practically satisfactory before and after the endurance test was obtained for each toner. The evaluation results are shown in Table 3.

<Comparative Examples 1 to 8>
The image output test was performed in the same manner as in Example 1 except that the toners 17 to 24 were used. As a result, image unevenness occurred and offset was also partially bad. In addition, the density of the toner 18 after endurance was 1.24, and the developability was low. The evaluation results are shown in Table 3.

  DESCRIPTION OF SYMBOLS 100 Electrostatic latent image carrier (photoconductor), 102 Toner carrier, 114 Transfer member (transfer roller), 116 Cleaner, 117 Contact charging member (charge roller), 121 Laser generator (latent image forming means, exposure device) , 123 Laser light, 124 Register roller, 125 Conveyor belt, 126 Fixing device, 140 Developer, 141 Stirring member

Claims (6)

A toner containing toner particles containing at least a binder resin, a colorant, and a release agent, and an inorganic fine powder,
The toner contains 5 to 20 parts by mass of the release agent with respect to 100 parts by mass of the binder resin.
Adhesive force when the toner is heated at 190 ° C. is 50 N / m ² or more and 500 N / m ² or less,
After the toner was dissolved in orthodichlorobenzene, the soluble content of the toner obtained by shaking for 24 hours at 25 ° C. was measured using size exclusion chromatography-online-multi-angle light scattering (SEC-MALLS). In the weight average molecular weight (Mw) and inertial square radius (Rw), the weight average molecular weight (Mw) is 50,000 to 200,000, and the ratio of the inertial square radius (Rw) to the weight average molecular weight (Mw) (Rw) / Mw) satisfies a relationship of 1.0 × 10 ⁻⁴ ≦ Rw / Mw ≦ 4.0 × 10 ⁻⁴ . 2. The toner according to claim 1, wherein the toner has an average circularity measured by using a flow type particle image measuring apparatus of 0.960 or more. 3. The toner according to claim 1, wherein a tetrahydrofuran (THF) insoluble content of the resin component of the toner is 15% by mass or more and 50% by mass or less with respect to the resin component. 4. The molecular weight distribution measured by gel permeation chromatography of a tetrahydrofuran (THF) soluble content of the toner has a peak molecular weight (Mp) of 12,000 or more and 18,000 or less. 5. The toner according to item. The release agent contains at least a release agent A and a release agent B, the solubility of the release agent A in styrene-acrylic resin is 3 or less, and the styrene-acrylic resin of the release agent B The toner according to claim 1, wherein a difference in solubility obtained by subtracting the solubility of the release agent A in the styrene-acrylic resin from the solubility in the toner is 5 or more and 20 or less. The toner according to claim 1, wherein the toner particles are toner particles produced by a suspension polymerization method.

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