JP6659141B2 - toner - Google Patents

Description

  The present invention relates to a toner used for electrophotography, electrostatic recording, magnetic recording, and the like.

2. Description of the Related Art In recent years, image forming apparatuses such as copying machines and printers have been required to cope with higher speeds and energy savings. In particular, with respect to a monochrome image forming apparatus, there is a high demand for improvement in image productivity, and there is also a demand for high-speed operation and further higher image quality.
Further, regardless of business use or personal use, there is a demand for a smaller apparatus than ever before, and there is a high demand for simplification and stabilization as a fixing system used therefor. For toner, a toner having a low fixing temperature and a wide fixing area has been demanded.

For energy saving of the image forming apparatus, it is effective to reduce the amount of heat at the time of fixing the toner to the paper, and the development of a toner capable of fixing at a lower temperature to the paper is actively performed. ing.
In order to cope with low-temperature fixing, a technique has been proposed in which a crystalline material such as a crystalline resin is contained in a toner (Patent Document 1). This technique is based on the fact that when the toner is exposed to heat in the nip of the fixing device, the binder resin of the toner is plasticized by a crystalline material, and the viscosity is reduced from a lower temperature side than before. .

JP 2013-156617 A JP-A-10-182163 JP-A-7-110598

However, with a toner containing a crystalline material, a minute gloss unevenness may occur in the obtained image or the storage stability of the image may be easily reduced depending on the fixing method and the constituent requirements of the toner.
In particular, in the case where the image is rapidly cooled after being fixed at a high temperature, such as continuous double-sided printing with a high-speed printer having a high printing speed, the storage stability of the obtained image tends to decrease.
Specifically, when the fixed image is left for a long time in a high-temperature and high-humidity environment, there is a problem that the toner fixed on the paper is more likely to be peeled off due to friction than before leaving (the fixing property before and after leaving) change). In particular, in recent years of higher image quality, the adverse effects tend to appear more easily.
Also, when thin paper with a low basis weight is used to output both sides of an image having a significantly different printing ratio between the front and back sides, if the obtained image is left for a long time in a high-temperature and high-humidity environment, the curling of the image may easily occur. (Image curl after standing).

Further, when a thick paper having a high basis weight is used and output, black granular stains may occur on a white background of an image (thick paper offset).
On the other hand, there have been many attempts to improve magnetic particles in magnetic toners used in monochrome image forming apparatuses (Patent Documents 2 and 3).
However, Patent Documents 2 and 3 do not mention the above problem at all. Further, it was difficult to obtain the effects of the present invention by improving these magnetic particles.
As described above, in order to cope with both high-speed operation and miniaturization, it is necessary to achieve both the expansion of the toner fixing area and the storage stability of the left image, but there is still room for improvement.
An object of the present invention is to provide a toner that solves the above problems.
That is, an object of the present invention is to provide a toner that has a wide fixing area, suppresses gloss unevenness, and has good image storage stability (change in fixing property before and after standing, image curl).

A toner having a binder resin, a crystalline material A, and toner particles containing magnetic particles,
The crystalline material A is a crystalline polyester resin having a unit derived from an aliphatic diol and a unit derived from an aliphatic dicarboxylic acid,
The toner, wherein the magnetic particles satisfy all of the following requirements (i) to (iii).
(I) having an octahedral shape, having a convex portion on a plane portion of the octahedron (ii) having a core containing magnetite particles, and a coating layer provided on the surface of the core (iii) the coating layer in addition to the oxide containing iron, it contains an oxide containing an oxide and aluminum containing silicon

  According to the present invention, in a monochrome high-speed printer, it is possible to obtain a toner that has a wide fixing area, suppresses gloss unevenness, and has good storage stability of an image (fixation change before and after leaving, image curl).

TEM photograph of magnetic particles of Example (drawing substitute photograph) TEM photograph of magnetic particles of comparative example (drawing substitute photograph) Schematic diagram of the method for measuring the height of the protrusions of the magnetic particles of the example

In the present invention, description of “XX or more and XX or less” or “XX to XX” representing a numerical range means a numerical range including a lower limit and an upper limit which are endpoints unless otherwise specified.
The present inventors have intensively studied to realize a toner having a wide fixing area, suppressing occurrence of gloss unevenness, and having excellent storage stability (change in fixing property before and after standing, image curl).
Generally, in a toner containing a crystalline material, at the time of heat fixing, the crystalline material plasticizes the binder resin of the toner and lowers the viscosity. After fixing, the toner whose viscosity has been reduced is rapidly cooled, and the crystallization of the crystalline material proceeds, and the crystalline material and the binder resin are often phase-separated. At this time, the difference in the crystallization speed causes a difference in the contraction force of the crystalline material, and the difference in the strain sometimes causes minute gloss unevenness on an image.
In particular, in recent years, higher image quality has progressed, and gloss unevenness, which has not been a problem in the past, has sometimes become a problem.
Therefore, it was found that to improve the gloss unevenness after fixing, it is necessary to increase the crystallization speed of the crystalline material in the toner after passing through the fixing nip.

In addition, the cause of easily causing curl in an image left in a high temperature and high humidity environment was also examined in detail. As a result, it was found that curling of the left image occurred due to a difference in the contraction force generated on the paper between the front surface and the back surface.
The difference in the contraction force on the paper is due to the difference in the thermal histories between the front and back surfaces and the difference in the image printing ratio. It was also found that this was caused by different degrees of crystallization in the process.
Therefore, it has been found that it is important to uniformly crystallize the crystalline material in the toner immediately after fixing in order to further improve the image curl after being left as it is.
Regarding image curl after standing in a high-temperature and high-humidity environment, the image is obtained by performing double-sided printing using thin paper with a low basis weight, using a high printing ratio image on the front surface and a low printing ratio image on the back surface. Most prominently, curling with a convex back surface is likely to occur.

The reason for this is not always clear, but it is presumed to be for the following reason.
First, the surface that receives more heat history tends to have a higher contraction force on the paper. This is because the crystallinity of the crystalline material immediately after fixing tends to decrease due to a large heat history, and a large amount of the crystalline material crystallizes during the standing process.
Next, as the printing ratio of the image is higher, the contraction force on the paper is likely to be higher. This is because the absolute amount of the fixing toner present on the paper increases, so that the amount of the crystalline material that has not crystallized immediately after fixing increases, and many crystalline materials crystallize during the standing process.
From the above, in order to further reduce the low-temperature fixing property and minute gloss unevenness and further improve the storage stability of the image, the crystallization speed of the crystalline material in the toner was increased, and the toner was cooled down rapidly after passing through the fixing nip. In the meantime, it was concluded that it was necessary to quickly increase the crystallinity.

In order to increase the crystallization speed of the toner after fixing while sufficiently exhibiting the plasticity of the crystalline material at the time of fixing, it is important to include magnetic particles having a specific surface shape. I found something.
The toner of the present embodiment is a toner having toner particles containing a binder resin, a crystalline material A, and magnetic particles,
The magnetic particles are toners satisfying all of the following requirements (i) to (iii).
(I) having an octahedral shape, having a convex portion on a plane portion of the octahedron (ii) having a core containing magnetite particles, and a coating layer provided on the surface of the core (iii) the coating layer And at least one oxide selected from the group consisting of oxides containing silicon and oxides containing aluminum in addition to oxides containing iron

It is not clear why the toner having such a configuration has excellent low-temperature fixability, little gloss unevenness, and excellent storage stability of an image, but the present inventors consider as follows. I have.
The magnetic particle of the present invention has an octahedral crystal structure, and has a convex portion on a plane portion of the octahedron. For this reason, the surface of the magnetic particles has a plurality of convex portions that easily support the crystalline material.
As a result, when the toner is melted in the fixing nip, the crystalline material gathers in the vicinity of the convex portion and is easily melted, so that the binder resin can be plasticized in a state where the crystalline material is finely dispersed at the time of fixing.

As a result, it is presumed that even in a fixing device such as a high-speed printer in which the transit time in the nip is short, the binder resin can be uniformly plasticized and the low-temperature fixing property can be improved.
On the other hand, it is presumed that since the crystalline material easily gathers near the convex portion, the convex portion acts as a crystal nucleating agent for the crystalline material after passing through the fixing nip.
The projections dramatically increase the generation speed and frequency of crystal nuclei of the crystalline material, and when the fixed image is rapidly cooled through the fixing nip, crystallization in the fixing toner proceeds rapidly and uniformly. It is presumed that this will lead to a reduction in gloss unevenness of the image and an improvement in storage stability.
In the present invention, the crystalline material A is not particularly limited, and a crystalline polyester resin or wax described later can be used.

<Preferred embodiment 1>
In the toner of the present invention, the crystalline material A is preferably a crystalline polyester resin.
In the magnetic particles of the present invention, the coating layer contains an oxide having a high affinity for the crystalline polyester resin, and has a projection on the octahedral plane. Therefore, it becomes easier to carry the crystalline polyester resin on the surface of the magnetic particles.
Thereby, the melting and crystallization of the toner in the fixing nip can be performed more quickly, and the effect of the present invention can be more easily obtained.
The coating layer is preferably the outermost layer. When the coating layer is the outermost layer, the crystalline polyester resin can be effectively supported.

Further, the crystalline material A is preferably a crystalline polyester resin having a unit derived from an aliphatic diol and a unit derived from an aliphatic dicarboxylic acid.
In the crystalline polyester resin of the present embodiment, the proportion of units derived from aliphatic diol is preferably 50 mol% or more and 100 mol% or less, and is preferably 80 mol% or more and 100 mol% or less. It is more preferably at most 90 mol%, more preferably at most 90 mol%.
Further, among units derived from all acid monomers, the proportion of units derived from aliphatic dicarboxylic acid is preferably from 50 mol% to 100 mol%, more preferably from 80 mol% to 100 mol%. More preferably, it is 90 mol% or more and 100 mol% or less.

Examples of the aliphatic diol include an aliphatic diol having 4 to 18 carbon atoms, and examples of the aliphatic dicarboxylic acid include an aliphatic dicarboxylic acid having 4 to 18 carbon atoms.
For example, as the aliphatic diol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, Examples thereof include 1,10-decanediol, 1,11-undecanediol, and 1,12-dodecanediol.
Examples of the aliphatic dicarboxylic acid compound include fumaric acid, 1,8-octanedioic acid, 1,9-nonanedioic acid, 1,10-decandioic acid, 1,11-undecandioic acid, and 1,12-dodecandioic acid. And the like.

The aliphatic diol is preferably an aliphatic diol having 6 to 12 carbon atoms in that the crystallization rate of the crystalline polyester resin becomes better and the storage stability of the obtained image becomes better. The aliphatic dicarboxylic acid is preferably an aliphatic dicarboxylic acid having 6 to 12 carbon atoms.
In the crystalline polyester resin, among the units derived from the aliphatic diol, the proportion of units derived from an aliphatic diol having 6 to 12 carbon atoms is 85 mol% to 100 mol% (more preferably 90 mol% or more). 100 mol% or less), and among the units derived from the aliphatic carboxylic acid component, the proportion of units derived from an aliphatic dicarboxylic acid having 6 to 12 carbon atoms is 85 mol% or more and 100 mol% or less (more preferably). Is preferably 90 mol% or more and 100 mol% or less.
With the crystalline polyester resin having the above configuration, the crystallization speed of the crystalline polyester resin in the fixing toner after passing through the fixing nip can be further increased. Therefore, it is preferable because a change in fixability before and after standing can be reduced.

Further, in the crystalline polyester resin, it is preferable that a unit derived from an aliphatic monoalcohol having 12 to 30 carbon atoms or an aliphatic monocarboxylic acid having 12 to 30 carbon atoms is bonded to a terminal of a molecular chain. . Thereby, the low-temperature fixability and the storage stability of the image can be further improved. Specifically, the reduction rate of the rubbing density immediately after fixing is good, the reduction rate of the rubbing density after leaving is good, and the curling of the image after leaving is also good.
This is because the unit derived from the aliphatic monoalcohol or aliphatic monocarboxylic acid having 12 or more and 30 or less carbon atoms is a unit having high crystallinity, so that the unit acts as an intramolecular nucleating agent for the crystalline polyester resin. The crystallization rate can be increased uniformly. It is also presumed that the unit has high affinity with the coating layer of the magnetic particles and can improve the dispersibility of the crystalline polyester resin, so that the plasticity at the time of fixing can be enhanced.

In the crystalline polyester resin, the addition amount of the aliphatic monoalcohol or aliphatic monocarboxylic acid having 12 to 30 carbon atoms, when the total amount of the alcohol monomer and the acid monomer constituting the crystalline polyester resin is 100 mol, It is preferable that the amount be 0.1 mol or more and 10.0 mol or less.
When the content is within the above range, the aliphatic monoalcohol or the aliphatic monocarboxylic acid can be uniformly bonded to the crystalline polyester resin, and the amount of unreacted substances is reduced. The amount is more preferably 0.2 mol or more and 5.0 mol or less from the viewpoint that the low-temperature fixability and the storage stability of the image become better.

The melting point of the crystalline polyester resin is preferably from 60.0 ° C. to 100.0 ° C., more preferably from 65 ° C. to 90 ° C., from the viewpoint of achieving both low-temperature fixability and image storage stability.
From the same viewpoint, the weight average molecular weight of the crystalline polyester resin is preferably from 10,000 to 100,000, more preferably from 20,000 to 40,000. The heat of fusion of the crystalline polyester resin is preferably from 60.0 J / g to 150.0 J / g, and more preferably from 75.0 J / g to 130.0 J / g.
The crystalline polyester resin preferably has an acid value of 1 mgKOH / g or more and 30 mgKOH / g or less from the viewpoints of chargeability and durability of the toner.
The content of the crystalline polyester resin in the toner is preferably 0.5 parts by mass or more and 10 parts by mass or less based on 100 parts by mass of the binder resin.

<Preferred embodiment 2>
Further, a configuration was studied in which the compatibility between the enlargement of the fixing area and the storage stability of the image can be better achieved.
It is known to use a plurality of crystalline materials having different melting points in order to enlarge the fixing area.However, simply improving the crystalline material can achieve a higher balance between the fixing area enlargement and image storage stability. It was difficult to achieve at the level. This is considered to be due to the compatibilization of the plurality of crystalline materials.
Therefore, why the compatibilized crystalline material is difficult to further improve the storage stability of an image was examined in detail.

As a result, the crystallization of the compatibilized crystalline material in the fixing toner proceeds while being left in a high-temperature and high-humidity environment. It was found that the shrinkage caused distortion, and the adhesion between the fixing toner and the paper was easily reduced.
In particular, a toner having a compatibilized crystalline material is divided into a component in which the original crystalline material is crystallized and a component in which the compatibilized material is crystallized. Also tend to be uneven.
That is, in the image immediately after fixing, it was found that the compatibilized crystalline component in the fixing toner hindered the improvement of the reduction rate of the rubbing density after standing.
Therefore, it was found that in order to further improve the reduction rate of the rubbing density after standing, it is necessary to increase the crystallization speed of the component having low crystallinity after passing through the fixing nip.

In addition, the cause of easily causing curl in an image left in a high temperature and high humidity environment was also examined in detail. As described above, the curl of the left image is caused by the difference in the contraction force generated on the paper between the front surface and the back surface.
In order to further improve the image curl after standing, it is important to uniformly crystallize a plurality of crystalline components in the toner immediately after fixing.

Further, the cause of the contamination (thick paper offset) on black particles generated on a white background of an image when a thick paper having a high basis weight is output was examined in detail.
Thick paper having a high basis weight has a high fixing pressure received from the fixing device, and the fixing roller and the toner are more likely to adhere to each other at the time of fixing. At that time, it was found that the component having a low degree of crystallinity was partially reduced in viscosity in the toner, the releasability was impaired, and small black spots were generated.
From the above, in order to further enhance the low-temperature fixability and the storage stability of an image, the crystallization speed of the crystalline material in the toner is increased, and the toner is rapidly cooled through the fixing nip until it is rapidly cooled. It was decided that the crystallinity had to be increased.

In order to increase the crystallization speed of the toner after fixing while sufficiently exhibiting the plasticity of the crystalline material during fixing, it is preferable to include magnetic particles having a specific surface shape.
In this embodiment, when the toner particles contain a crystalline material B in addition to the crystalline material A, and the melting point of the crystalline material A is Ma (° C.) and the melting point of the crystalline material B is Mb (° C.) It is preferable that the following formula (1) is satisfied.
5 ≦ Mb−Ma ≦ 50 (1)

  When the difference (Mb-Ma) in the melting point is in the above range, rapid crystallization can be achieved, which is a more preferable embodiment. The Mb-Ma (° C.) is more preferably 10 or more and 40 or less.

The magnetic particles have a convex portion on the plane portion of the polyhedron-shaped covering layer. Therefore, the surface of the magnetic particles has a large number of convex portions that easily support the crystalline material.
As described above, it is presumed that the crystalline material easily gathers in the vicinity of the convex portion, so that the convex portion acts as a crystal nucleating agent for the crystalline material after passing through the fixing nip.

When crystalline materials having different melting points are crystallized, first, the high melting point component is crystallized in the vicinity of the projection, and then the low melting point component is crystallized. Therefore, it is considered that crystalline materials having different melting points can be rapidly crystallized without being mutually compatible.
Further, it is considered that the crystalline material having a high melting point acts as a crystal nucleating agent for the crystalline material having a low melting point, thereby increasing the crystallization speed of the entire crystalline material.
As a result, the generation rate and generation frequency of crystal nuclei of the crystalline material are dramatically increased by the convex portions, and when the fixed image is rapidly cooled through the fixing nip, the crystallization in the fixing toner proceeds rapidly. It is presumed that the storage stability of the image can be improved by doing so.
In the present embodiment, the crystalline material A and the crystalline material B can be used without any limitation as long as the material has crystallinity, such as a crystalline polyester resin or a wax.

The crystalline polyester resin is preferably a crystalline polyester resin having a unit derived from an aliphatic diol and a unit derived from an aliphatic dicarboxylic acid. As the crystalline polyester resin, those described above can be used.
By having a unit derived from the aliphatic diol and a unit derived from the aliphatic dicarboxylic acid, the affinity with the above-mentioned coating layer is increased, and the crystalline polyester resin is easily collected near the surface of the magnetic particles.
Thereby, the plasticity of the crystalline polyester resin increases near the surface of the magnetic particles at the time of fixing, so that the low-temperature fixing property is excellent.
In addition, the contact probability between the above-mentioned convex portions of the magnetic particles and the crystalline polyester resin is increased, the crystallization speed of the crystalline polyester resin after passing through the fixing nip is increased, and the storage stability of the image is also excellent.
When the content of the crystalline polyester resin in the toner is 0.5 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the binder resin, the balance between low-temperature fixability and image storage stability is improved. Therefore, it is preferable.

Examples of the wax include hydrocarbon waxes such as polyolefin copolymer, polyolefin wax, microcrystalline wax, paraffin wax, Fischer-Tropsch wax, and ester wax.
Further, there is a wax obtained by sharpening the molecular weight distribution of these waxes by a press sweating method, a solvent method, a recrystallization method, a vacuum distillation method, a supercritical gas extraction method or a molten liquid crystal deposition method.
Specific examples of the wax include the following.
Viscol (registered trademark) 330-P, 550-P, 660-P, TS-200 (Sanyo Chemical Industries, Ltd.), high wax 400P, 200P, 100P, 410P, 420P, 320P, 220P, 210P, 110P (Mitsui Chemicals, Inc.) ), Sasol H1, H2, C80, C105, C77 (Schumann Sasol), HNP-1, HNP-3, HNP-9, HNP-10, HNP-11, HNP-12 (Nippon Seiro Co., Ltd.), Unilin (registered trademark) 350, 425, 550, 700, Unisid (registered trademark), Unisid (registered trademark) 350, 425, 550, 700 (Toyo Adress Co., Ltd.), wood wax, beeswax, rice wax, candelilla wax , Carnauba Wax (available from Celarica NODA).

The timing of adding the wax may be during the production of the toner, or may be during the production of the binder resin, and is appropriately selected from existing methods. These waxes may be used alone or in combination.
The melting point of the wax is preferably from 60.0 ° C to 125.0 ° C, more preferably from 65 ° C to 120 ° C, from the viewpoint of achieving a balance between low-temperature fixability and storage stability of an image.
From the viewpoint of controlling the crystallization rate, the heat of fusion of the wax is preferably from 100 J / g to 300 J / g, more preferably from 150 J / g to 250 J / g.
The acid value of the wax is preferably 1 mgKOH / g or more and 30 mgKOH / g or less from the viewpoint of the chargeability and durability of the toner.
When the content of the wax in the toner is 0.5 parts by mass or more and 6.0 parts by mass or less with respect to 100 parts by mass of the binder resin, the balance between low-temperature fixability and image storage stability is improved. preferable.

More preferably, the crystalline material A is a crystalline polyester resin and the crystalline material B is a hydrocarbon wax.
Generally, the hydrocarbon wax has a low molecular weight and a high crystallinity. Therefore, when the toner is cooled, the hydrocarbon wax first crystallizes. Thereafter, the crystalline polyester resin crystallizes. At that time, the wax already crystallized becomes a crystal nucleating agent, and promotes crystallization of the crystalline polyester resin. As a result, the crystallization speed is improved, and the crystalline material is uniformly dispersed, which is more preferable for obtaining the effects of the present invention.

<Preferred embodiment 3>
Furthermore, a configuration that can better achieve both the enlargement of the fixing area and the storage stability of the image was studied.
To expand the fixing area, it is known to use a crystalline material having a wide half-width of the endothermic peak.However, simply improving the crystalline material can achieve both fixing area expansion and image storage stability. It was difficult to achieve at a higher level. Then, it was examined in detail why it is difficult to further improve the storage stability of an image when a crystalline material having a wide half width is used.

As a result, while left in a high-temperature and high-humidity environment, the crystallization of the crystalline material in the fixing toner proceeds, and phase separation from the binder resin and shrinkage caused by the densification of the crystalline material occur. It was found that distortion occurred and the adhesiveness between the fixing toner and the paper was easily reduced. In particular, in the case of a toner having a wide half-value width, the crystalline state of the crystalline material is not uniform, so that the crystallization speed tends to be uneven.
In other words, it was found that in the image immediately after fixing, the component having a low crystallinity of the crystalline material in the fixing toner hindered the improvement of the reduction rate of the rubbing density after standing.
Therefore, it was found that in order to further improve the reduction rate of the rubbing density after standing, it is necessary to increase the crystallization speed of the component having a low crystallinity of the crystalline material after passing through the fixing nip.

In addition, the cause of easily causing curl in an image left in a high temperature and high humidity environment was also examined in detail.
As a result, as described above, the curl of the left image is caused by the difference in the contraction force generated on the paper between the front surface and the back surface.
The difference in the contraction force on the paper is due to the difference in the thermal history between the front and back surfaces and the difference in the image printing ratio. It was also found that this was caused by different degrees of crystallization in the process.

  Therefore, it is important to uniformly crystallize the crystalline material in the toner immediately after fixing in order to further improve the image curl after being left.

Further, the cause of the contamination (thick paper offset) on black particles generated on a white background of an image when a thick paper having a high basis weight is output was examined in detail.
Thick paper having a high basis weight has a high fixing pressure received from the fixing device, and the fixing roller and the toner are more likely to adhere to each other at the time of fixing. At that time, it was found that the component having a low crystallinity of the crystalline material was partially reduced in viscosity in the toner, the releasability was impaired, and small black spots were generated.

From the above, in order to further improve the low-temperature fixability and the storage stability of an image, the crystallization speed of the entire crystalline material in the toner is increased, and the toner is rapidly cooled before passing through the fixing nip and being rapidly cooled. It was concluded that the crystallinity needed to be increased.
In order to increase the crystallization speed of the toner after fixing while sufficiently exhibiting the plasticity of the crystalline material during fixing, it is preferable to include magnetic particles having a specific surface shape.

In this embodiment, the crystalline material A is heated to 200 ° C. at a rate of 10 ° C./min, cooled to −10 ° C. at a rate of 10 ° C./min, and further cooled to 200 ° C. using a differential scanning calorimeter. Has an endothermic peak in the second heating process measured by heating at a heating rate of 10 ° C./min to
The temperature P at the peak top of the endothermic peak is 60 ° C. or more and 120 ° C. or less,
It is preferable that the half width W1 of the endothermic peak is from 10 ° C to 50 ° C.

The magnetic particles have a convex portion on the plane portion of the polyhedron-shaped covering layer. Therefore, the surface of the magnetic particles has a large number of convex portions that easily support the crystalline material A. As a result, when the toner is melted in the fixing nip, the crystalline material A gathers in the vicinity of the convex portion and is easily melted, so that the binder resin is plasticized in a state where the crystalline material A is finely dispersed at the time of fixing. it can.
As a result, it is presumed that even in a fixing device such as a high-speed printer in which the transit time in the nip is short, the binder resin can be uniformly plasticized and the low-temperature fixing property can be improved. On the other hand, it is presumed that since the crystalline material A easily gathers near the convex portion, the convex portion acts as a crystal nucleating agent of the crystalline material A after passing through the fixing nip.

Further, when the crystalline material A having a wide half width is crystallized, the high melting point component is first crystallized, and then the low melting point component is crystallized. Therefore, it is considered that the high melting point component also acts as a crystal nucleating agent for the low melting point component and increases the crystallization speed of the entire crystalline material A.
The projections dramatically increase the generation rate and frequency of crystal nuclei of the crystalline material A, and the crystallization in the fixing toner proceeds rapidly when the fixed image passes through the fixing nip and is rapidly cooled. It is speculated that the storage stability of the image can be improved.
The peak temperature P of the endothermic peak of the crystalline material A in the present embodiment is more preferably 80 ° C. or more and 110 ° C. or less from the viewpoint of achieving both low-temperature fixability and image storage stability. In addition, from the viewpoint of increasing the crystallization speed, it is more preferable that the half-value width W1 of the endothermic peak is from 12 ° C to 30 ° C.
The peak top temperature P can be controlled by the molecular weight of the crystalline material A, the polymer composition, and the like. Further, the half width W1 can be controlled by the molecular weight distribution of the crystalline material A, the manufacturing method, and the like.

As the crystalline material A in this embodiment, the above-mentioned crystalline polyester or wax can be used.
The timing of adding the crystalline material A may be during the production of the toner or may be during the production of the binder resin, and is appropriately selected from existing methods. These crystalline materials A may be used alone or in combination. In this embodiment, from the viewpoint of controlling the crystallization rate, the heat of fusion of the crystalline material A is preferably from 100 J / g to 300 J / g, and more preferably from 150 J / g to 250 J / g.
The acid value of the crystalline material A is preferably 1 mgKOH / g or more and 30 mgKOH / g or less from the viewpoint of the chargeability and durability of the toner.
When the content of the crystalline material A in the toner is 0.5 parts by mass or more and 6.0 parts by mass or less with respect to 100 parts by mass of the binder resin, the balance between low-temperature fixability and image storage stability is good. Is preferable.

<Magnetic particles>
The magnetic particles used in the present invention,
(I) It is necessary to have a core containing magnetite particles and a coating layer provided on the surface of the core.
The magnetite particles may contain other metals in addition to magnetite to such an extent that the effect of the present invention is not impaired. For example, hematite, iron oxides such as ferrite, iron, cobalt, metals such as nickel, or these metals and aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony, bismuth, calcium, manganese, titanium, Alloys with metals such as tungsten, vanadium and mixtures thereof.
When the core is magnetite particles, the magnetic properties and coloring power of the magnetic particles are sufficient.

The coating layer may cover the entire surface of the core evenly, or may cover the core in a partially exposed state. Regardless of the coating mode, the coating layer preferably thinly covers the surface of the core.
When the coated magnetic particles are observed by TEM, the thickness of the coating layer is preferably from 1 nm to 50 nm, more preferably from 2 nm to 20 nm.
The thickness of the coating layer is determined by TEM observation of the coated magnetic particles, measuring the thickness of the coating layer at 15 or more positions, and arithmetically averaging the measured values. The thickness of the coating layer does not include the size of the above-mentioned protrusion.

Further, the coating layer of the magnetic particles needs to contain at least one oxide selected from the group consisting of an oxide containing silicon and an oxide containing aluminum in addition to the oxide containing iron.
According to the study of the present inventors, the coating layer of the magnetic particles contains an oxide containing iron and at least one oxide selected from the group consisting of an oxide containing silicon and an oxide containing aluminum. In addition, the low-temperature fixability and the storage stability of an image can be improved for the first time by having a shape in which a convex portion is formed in a plane portion of a polyhedral shape described later.

When the coating layer does not contain an oxide containing iron or does not contain an oxide containing silicon and an oxide containing aluminum, affinity with a crystalline material such as a crystalline resin or a wax is reduced. Therefore, it becomes difficult for crystalline materials such as crystalline resin and wax to collect on the surface of the magnetic particles.
Therefore, the plasticity of the crystalline material at the time of fixing becomes insufficient, and the low-temperature fixability decreases.
For the same reason, the effect of the nucleating agent on the surface of the magnetic particles is less likely to be exhibited, so that the crystallization speed is reduced and the storage stability of the image is reduced.

The respective proportions of silicon, aluminum and iron contained in the coating layer, with respect to silicon, are preferably 5% by mass or more and 30% by mass or less based on the total mass of silicon, aluminum and iron contained in the coating layer. And more preferably 7% by mass or more and 20% by mass or less.
With respect to aluminum, the content is preferably from 10% by mass to 45% by mass, more preferably from 13% by mass to 42% by mass, based on the total mass of silicon, aluminum and iron contained in the coating layer. More preferably, it is not less than 37% by mass and not more than 37% by mass.
Regarding iron, the content is preferably from 40% by mass to 83% by mass, more preferably from 42% by mass to 80% by mass, based on the total mass of silicon, aluminum and iron contained in the coating layer. The content is more preferably from 78% by mass to 78% by mass.

Further, in order for the coated magnetite particles of the present invention to have a plurality of convex portions on the surface of the coating layer, the molar ratio of silicon to iron in the coating layer is 0.2 or more and 1.0 or less, particularly 0.3 or more. It is preferably 0.9 or less, and the molar ratio of aluminum to iron is 0.5 or more and 2.0 or less, particularly preferably 0.5 or more and 1.8 or less.
The ratio of these elements and the like is determined by suspending 25 g of the coated magnetite particles of the present invention in 5 L of 5% by mass of dilute sulfuric acid at 50 ° C. to obtain a measurement solution. (15, 25, 35, 45, 60, 75, 90, 105, 120 minutes) and sampled by a membrane filter, and the concentration of silicon, aluminum and iron contained in the filtrate obtained by ICP was measured by ICP. It can be measured by quantification. In this measurement, the total amount of iron eluted by the time when the detected amounts of silicon and aluminum became constant is regarded as the amount of iron in the coating layer.

The ratio of the total mass of silicon, aluminum and iron in the coating layer to the coating magnetite particles is preferably from 1.0% by mass to 5.5% by mass, and preferably from 1.8% by mass to 4.1% by mass. It is more preferred that: By forming the coating layer in this range, the resistance of the coated magnetite particles can be sufficiently increased. In addition, the dispersibility in the resin can be sufficiently increased.
The ratio of the total mass of silicon, aluminum, and iron in the coating layer to the coating magnetite particles was determined by suspending 25 g of the coating magnetite particles of the present invention in 5 L of 5% by mass diluted sulfuric acid at 50 ° C. to obtain a measurement liquid. A part of the measurement solution was sampled at regular intervals (5, 15, 25, 35, 45, 60, 75, 90, 105, and 120 minutes) by 25 mL, and this was filtered through a membrane filter to obtain a filtrate. It can be measured by quantifying the concentrations of Si, Al and Fe contained by ICP. In this measurement, the total amount (g) of each of silicon, aluminum and iron up to the point where the detected amounts of silicon and aluminum became constant is divided by 25 g, and multiplied by 100 to calculate the ratio of each element.

  The magnetic particles of the present invention have an octahedral shape, and need to have a convex portion on a plane portion of the octahedron. When the magnetic particles are octahedral, the magnetic particles have many flat portions, so that crystal growth of a crystalline material such as a crystalline resin or wax is easily promoted.

In addition, it is preferable that the protruding portion is composed of one or more fine particles of the iron-containing oxide. As shown in FIG. 1, when the coated magnetic particles are observed with a TEM, the protrusions are observed to have a size of about several nm.
Specifically, the size is preferably 1 nm or more and 40 nm or less, more preferably 7 nm or more and 20 nm or less. The size of the convex portion refers to a height that protrudes from the base surface of the coating layer when the coated magnetic particles are observed with a TEM. The projections may be present on the surface of the coating layer without gaps, or may be present as sparse as the base surface of the coating layer (ie, the reference surface on which the projections rise) is observed by TEM. Good.
The size of the projections was measured by TEM observation of the coated magnetic particles, and measuring the height h from the base surface of the coating layer to the apex of the projections for 15 or more projections as shown in FIG. It is determined by arithmetically averaging the measured values.
In addition, the convex part may exist in the plane part of a polyhedron without a clearance gap, and may exist sparsely. The number of the protrusions is not particularly limited, but it is sufficient that at least one protrusion is provided for one magnetic particle.

Further, in order for the magnetic particles of the present invention to have a convex portion in the plane portion of the polyhedron, the molar ratio of silicon to iron in the coating layer is preferably 0.2 or more and 1.0 or less, and 0.3 More preferably, it is 0.9 or less. Further, the molar ratio of aluminum to iron is preferably 0.5 or more and 2.0 or less, and more preferably 0.5 or more and 1.8 or less.
The height of the projections can be adjusted by changing the molar ratio of silicon to iron, the molar ratio of aluminum to iron, and the number average particle diameter of core particles in the coating layer.
The proportions of these elements are determined by suspending the coated magnetite particles of the present invention in 5% by mass of dilute sulfuric acid at 50 ° C. to obtain a measurement solution, and sampling a part of the measurement solution at regular intervals. Can be measured by quantifying the concentration of silicon, aluminum and iron contained in the filtrate obtained by filtration through a membrane filter by ICP. In this measurement, the amount of iron dissolved until silicon and aluminum are no longer detected is regarded as the amount of iron in the coating layer.

Only when the surface of the magnetic particles not only contains a specific coating layer but also has an octahedral shape, an excellent nucleating agent effect on a crystalline material such as a crystalline resin or a wax is exhibited. This is preferable because the crystallization speed of a crystalline material such as a crystalline resin or a wax after passing through the fixing nip can be drastically increased, and a toner having excellent image storage stability can be obtained.
By having an octahedral shape, the reason why a crystal nucleating agent effect is exerted on a crystalline material such as a crystalline resin or a wax is not clear, but it is probably that the crystalline material gathers at the projections to form a crystal nucleus, The present inventors presume that crystal growth is promoted along the octahedral plane.
When the shape of the magnetic particles is not octahedral, the storage stability of the image becomes insufficient because the nucleating agent effect on the crystalline material is low. Even when the octahedron does not have a convex portion in the plane portion, the storage stability of the image becomes insufficient because of the low nucleating agent effect.
As a method of making the magnetic particles into an octahedral shape, for example, in the production of the core particles, the pH during the oxidation reaction is set to 9 or more.

The magnetic particles preferably have a number average particle size of 50 nm or more and 200 nm or less, and more preferably 50 nm or more and 150 nm or less, from the viewpoint of improving the low-temperature fixability. As described below, the number average particle diameter of the primary particles of the magnetic particles is determined by measuring 100 particles by SEM observation and using the average value. The number average particle diameter of the primary particles of the magnetic particles can be controlled by conditions for synthesizing the magnetic particles and the like.
When the magnetic particles have a total pore volume of 0.060 cm ³ / g or more and 0.150 cm ³ / g or less, it is preferable because the storage stability of the image, particularly the curl of the image after standing, becomes better. More preferably not more than 0.060cm ³ / g or more 0.100cm ³ / g.
The total pore volume is determined not only by the number average particle diameter of the primary particles of the magnetic particles, but also by the number and height of the projections on the surface of the magnetic particles. The total pore volume can be controlled by the conditions for synthesizing the magnetic particles and the like.

When the total pore volume of the magnetic particles is in the above range, the dispersibility of the magnetic particles in the toner becomes better, and the crystalline resin or wax is easily carried on the surface of the magnetic particles. This is preferable because the action is uniformly exhibited.
The amount of the magnetic particles contained in the toner is preferably 30 parts by mass to 100 parts by mass, more preferably 40 parts by mass to 80 parts by mass, based on 100 parts by mass of the binder resin. Within this range, the balance between low-temperature fixability and coloring power is good.

<Binder resin>
Next, the binder resin used for the toner particles of the present invention will be described below.
Examples of the binder resin include a polyester resin, a vinyl-based resin, an epoxy resin, and a polyurethane resin, and a polyester resin is preferable in consideration of the plasticity at the time of fixing with a crystalline material.
The alcohol component and the acid component that can be used when synthesizing the polyester resin component are as follows.
Examples of the alcohol component include the following. Ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol , 2-ethyl-1,3-hexanediol, bisphenol A hydride, and aromatic diols include bisphenols represented by the following formula (I) and derivatives thereof, and diols represented by the following formula (II). Can be

Examples of the acid component include the following. Benzenedicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and phthalic anhydride or their anhydrides; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid or their anhydrides; Succinic acids or anhydrides substituted with the following alkyl groups or alkenyl groups; unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, and itaconic acid, or anhydrides thereof.
Examples of the trihydric or higher polyhydric alcohol component include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, and 1,2,4-butanetriol. , 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, and 1,3,5-trihydroxybenzene. Can be

  Examples of the trivalent or higher polycarboxylic acid component include trimellitic acid, pyromellitic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxy-2-methyl-2-methylenecarboxypropane, tetra (methylene Carboxy) methane, 1,2,7,8-octanetetracarboxylic acid, empol trimer acid, and anhydrides thereof.

The polyester resin is usually obtained by commonly known condensation polymerization.
On the other hand, as a vinyl-based monomer for producing a vinyl-based resin, the following can be mentioned.
Styrene and its derivatives such as styrene and o-methylstyrene; styrene unsaturated monoolefins such as ethylene and propylene; unsaturated polyenes such as butadiene and isoprene; vinyl esters such as vinyl chloride; methyl methacrylate Α-methylene aliphatic monocarboxylic esters such as n-butyl methacrylate and 2-ethylhexyl methacrylate; acrylic esters such as n-butyl acrylate and 2-ethylhexyl acrylate; vinyl methyl ether Vinyl ethers; vinyl ketones such as vinyl methyl ketone; N-vinyl compounds such as N-vinyl pyrrole; vinyl naphthalenes; acrylic acid or methacrylic acid derivatives such as acrylonitrile.

Further, the following may be mentioned. Unsaturated dibasic acids such as maleic acid and alkenyl succinic acid; unsaturated dibasic acid anhydrides such as maleic anhydride and alkenyl succinic anhydride; Unsaturated dibasic acid esters; α, β-unsaturated acids such as acrylic acid and methacrylic acid; α, β-unsaturated acid anhydrides such as crotonic anhydride and cinnamic anhydride; -Anhydrides of unsaturated acids and lower fatty acids; monomers having a carboxy group such as alkenyl malonic acid, alkenyl glutaric acid, alkenyl adipic acid, acid anhydrides and monoesters thereof.
Further, acrylic acid or methacrylic acid esters such as 2-hydroxyethyl acrylate; and hydroxy groups such as 4- (1-hydroxy-1-methylbutyl) styrene and 4- (1-hydroxy-1-methylhexyl) styrene. And a monomer having the same.

In the toner of the present invention, the vinyl resin may have a cross-linked structure cross-linked by a cross-linking agent having two or more vinyl groups. Examples of the crosslinking agent include aromatic divinyl compounds (particularly, divinylbenzene) and diacrylate compounds linked by a chain containing an aromatic group and an ether bond.
These crosslinking agents can be used in an amount of from 0.01 to 10.00 parts by mass, more preferably from 0.03 to 5.00 parts by mass, based on 100 parts by mass of the other monomer components.

The binder resin of the present invention may be a hybrid resin in which a polyester resin and a vinyl resin are combined.
When the binder resin of the present invention is a hybrid resin, it is preferable that the vinyl resin and / or the polyester resin component include a monomer component capable of reacting with both resin components. Among the monomers constituting the polyester resin component, those which can react with the vinyl resin include, for example, unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid and itaconic acid or anhydrides thereof. Among the monomers constituting the vinyl-based resin component, those which can react with the polyester resin component include those having a carboxy group or a hydroxy group, and acrylic acid or methacrylic acid esters.
As a method for obtaining a reaction product of a vinyl resin and a polyester resin, where a polymer containing a monomer component capable of reacting with each of the above-mentioned vinyl resin and the polyester resin is present, one or both of the two may be used. A method obtained by polymerizing a resin is preferred.

The glass transition temperature (Tg) of the binder resin is preferably 50 ° C. or more and 75 ° C. or less from the viewpoint of storage stability of the raw materials.
Further, from the same viewpoint, the softening point is preferably 80 ° C. or more and 150 ° C. or less.
The weight average molecular weight of the binder resin is preferably from 8,000 to 120,0000, more preferably from 40,000 to 300,000, from the viewpoints of the durability and the fixing property of the toner.
Further, in the chart of the molecular weight distribution of the tetrahydrofuran-soluble component measured by gel permeation chromatography of the binder resin, the area ratio of the molecular weight of 2000 or less is 5.0 area% or less with respect to the entire area of the chart. Is preferred.

The acid value of the resin used as the binder resin is preferably 2 mgKOH / g or more and 40 mgKOH / g or less from the viewpoint of the durability of the toner and the charge rising property.
The resin used as the binder resin may be one type, or a plurality of types may be used in combination.
Further, in the toner of the present invention, in order to achieve the above-mentioned image preservability, in the molecular weight distribution chart of the tetrahydrofuran-soluble component of the toner measured by gel permeation chromatography, the area ratio of the molecular weight of 2000 or less is the chart. It is preferable that it is 5.0 area% or less with respect to the whole area. More preferably, it is 4.5 area% or less.
The above range is preferable from the viewpoint of increasing the crystallization speed. The area ratio can be controlled by the monomer composition of the binder resin, the production method, and the like.

<Release agent>
The wax is not limited to a specific form and may be used as a release agent.
The release agent may be added during the production of the toner or at the time of production of the binder resin, and may be appropriately selected from existing methods. These release agents may be used alone or in combination.
The release agent is preferably added in an amount of 0.5 parts by mass or more and 20.0 parts by mass or less based on 100.0 parts by mass of the total amount of the binder resin.
The melting point peak temperature of the release agent is preferably from 60 ° C. to 120 ° C., more preferably from 70 ° C. to 110 ° C., from the viewpoints of durability and low-temperature fixability of the toner.

<Other ingredients>
The toner of the present invention is a magnetic toner, but may contain other colorants. Other colorants may include carbon black as a black colorant, and those toned to black using a yellow / magenta / cyan colorant.

Further, a charge control agent can be used in the toner in order to stabilize its triboelectric charging property. As the charge control agent, those that control the toner to be negatively charged and those that control the toner to be positively charged are known. Depending on the type and use of the toner, one or more kinds of various types may be used. Can be.
The following are examples of controlling the toner to be negatively charged. Organometallic complexes (monoazo metal complexes; acetylacetone metal complexes); metal complexes or metal salts of aromatic hydroxycarboxylic acids or aromatic dicarboxylic acids. In addition, examples of a device that controls the toner to be negatively charged include aromatic mono- and polycarboxylic acids and metal salts and anhydrides thereof; esters and phenol derivatives such as bisphenol. Among these, a metal complex or a metal salt of an aromatic hydroxycarboxylic acid that can provide stable charging performance is particularly preferably used.

  The following are examples of devices that control the toner to be positively charged. Modified products of nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and oniums such as phosphonium salts which are analogs thereof Salts and lake pigments thereof; triphenylmethane dyes and lake pigments thereof (phosphorotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanic acid, Russian compounds, etc.); metal salts of higher fatty acids. In the present invention, these can be used alone or in combination of two or more. Among these, a charge control agent such as a nigrosine compound or a quaternary ammonium salt is particularly preferably used to control the toner to be positively chargeable.

  The following are specific examples. Spiron Black TRH, T-77, T-95, TN-105 (Hodogaya Chemical Industry Co., Ltd.); BONTRON (registered trademark) S-34, S-44, E-84, E-88 (Orient Chemical Industry Co., Ltd.) ); TP-302, TP-415 (Hodogaya Chemical Industry Co., Ltd.); BONTRON (registered trademark) N-01, N-04, N-07, P-51 (Orient Chemical Industry Co., Ltd.); Copy Blue PR ( Clariant).

<Production method>
The toner particles according to the present invention are preferably manufactured by a pulverization method. An example of the manufacturing method will be described below.
i) mixing the binder resin, the crystalline material A, the magnetic material, the crystalline material B and other additives, etc. with a mixer such as a Henschel mixer or a ball mill ii) biaxially kneading the resulting mixture Melt kneading using a hot kneader such as an extruder, a heating roll, a kneader, or an extruder iii) Cooling and solidifying the obtained melt-kneaded material, and pulverizing iv) Classifying the obtained finely pulverized material Is performed, toner particles can be obtained.

In order to control the shape and surface properties of the toner particles, it is preferable to have a surface treatment step after pulverization or classification.
The following are mentioned as a mixing machine. Henschel Mixer (Mitsui Mining); Super Mixer (Kawata); Ribocorn (Okawara Seisakusho); Nauta Mixer, Turbulizer, Cyclomix (Hosokawa Micron); Spiral Pin Mixer (Taikai Kiko) Ledige mixer (Matsubo).
Examples of the kneader include the following. KRC Kneader (Kurimoto Iron Works); Bus Co Kneader (Buss); TEM Extruder (Toshiba Machine); TEX Twin Screw Kneader (Japan Steel Works); PCM Kneader (Ikegai) Iron mill); Three-roll mill, mixing roll mill, kneader (manufactured by Inoue Seisakusho); Kneedex (manufactured by Mitsui Mining); MS type pressure kneader, nider ruder (manufactured by Moriyama Seisakusho); Banbury mixer (Kobe Steel) Manufactured by Toshosha).

Examples of the crusher include the following. Counter Jet Mill, Micron Jet, Inomaizer (manufactured by Hosokawa Micron); IDS-type Mill, PJM Jet Crusher (manufactured by Nippon Pneumatic); Cross Jet Mill (manufactured by Kurimoto Tekkosho); Urmax (manufactured by Nisso Engineering) ); SK Jet O Mill (manufactured by Seishin Enterprise); Kryptron (manufactured by Kawasaki Heavy Industries); Turbo Mill (manufactured by Turbo Kogyo); Super Rotor (manufactured by Nisshin Engineering).
The classifier includes the following. Classile, Micron Classifier, Spedd Classifier (Seishin Enterprise); Turbo Classifier (Nisshin Engineering); Micron Separator, Turboplex (ATP), TSP Separator (Hosokawa Micron); Elbow Jet (Japan) Iron Mining Co., Ltd.), dispersion separator (Nippon Pneumatic Industries Co., Ltd.); YM Microcut (Yaskawa Shoji Co., Ltd.).

Examples of the surface modification device include Faculty (Hosokawa Micron), Mechanofusion (Hosokawa Micron), Novirta (Hosokawa Micron), Hybridizer (Nara Machinery), Inomaizer (Hosokawa Micron), Theta Composer (Manufactured by Tokuju Kosakusho) and Mechano Mill (manufactured by Okada Seiko).
Examples of the sieving apparatus used for sifting coarse particles include the following. Ultrasonic (made by Koei Sangyo Co., Ltd.); resonator sieve, gyro shifter (made by Tokuju Kogyo Co., Ltd.); Vibrasonic system (made by Dalton Co., Ltd.); Sonic Clean (made by Shinto Kogyo Co., Ltd.); Micro shifter (manufactured by Makino Sangyo); circular vibrating screen.

<External additives>
In the toner of the present invention, it is preferable to add a fluidity improver having a small particle diameter (the number average particle diameter of the primary particle diameter is about 5 to 30 nm) in order to improve the fluidity and chargeability of the toner.
As the fluidity improver, for example, fluorine resin powder such as vinylidene fluoride fine powder, polytetrafluoroethylene fine powder; wet-process silica, fine-powder silica such as dry-process silica, fine-powder titanium oxide, Fine powder alumina, silica treated with a silane compound, titanium coupling agent, and silicone oil for surface treatment; oxides such as zinc oxide and tin oxide; strontium titanate, barium titanate, calcium titanate, zirconate Double oxides such as strontium and calcium zirconate; and carbonate compounds such as calcium carbonate and magnesium carbonate.

Preferred fluidity improvers are fine powders produced by the vapor phase oxidation of silicon halides, and are so-called dry silica or fumed silica. For example, it utilizes the thermal decomposition oxidation reaction of silicon tetrachloride gas in an oxyhydrogen flame, and the basic reaction formula is as follows.
SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl
In this production step, it is also possible to obtain a composite fine powder of silica and another metal oxide by using another metal halide compound such as aluminum chloride or titanium chloride together with the silicon halide compound. I do.

Examples of commercially available fine silica powder produced by vapor phase oxidation of a silicon halide compound include the following. AEROSIL (Nippon Aerosil) 130, 200, 300, 380, TT600, MOX170, MOX80, COK84, Ca-O-SiL (CABOT Co.) M-5, MS-7, MS-75, HS-5, EH -5, Wacker HDK N20 (WACKER-CHEMIE GMBH) V15, N20E, T30, T40, DC Fine Silica (Dow Corning Co.), Fransol (Fransil).
Further, as the fluidity improver used in the present invention, a treated silica fine powder obtained by subjecting a silica fine powder generated by vapor-phase oxidation of the silicon halide to a hydrophobizing treatment is more preferable. The fluidity improver preferably has a specific surface area by nitrogen adsorption measured by the BET method of 30 m ² / g or more and 300 m ² / g or less.

Next, methods for measuring various physical properties according to the present invention will be described.
<Method of analyzing elements in coating layer of magnetic particles>
After the magnetic particles of the present invention are suspended in 5% by mass of dilute sulfuric acid at 50 ° C. to obtain a measurement solution, a part of the measurement solution is sampled at regular intervals. . This is measured and determined by quantifying the concentration of silicon, aluminum and iron contained in the filtrate obtained by filtration through a membrane filter by ICP. In this measurement, the amount of iron dissolved until silicon and aluminum are no longer detected is regarded as the amount of iron in the coating layer.

<Method of measuring number average particle diameter of primary particles of magnetic particles and confirming shape of magnetic particles>
In the present invention, the number average particle diameter of the primary particles of the magnetic particles is measured by observing the magnetic particles with a scanning electron microscope (JSM-6830F, manufactured by JEOL Ltd.) at a magnification of 30,000, and measuring 100 particles of arbitrary magnetic particles. The diameter (maximum diameter) was measured, and the average value of the measurement results of 100 particle diameters was defined as the number average particle diameter of the primary particles of the magnetic particles in the present invention.
Whether or not the shape of the magnetic particles was octahedral was determined from the shapes of the 100 magnetic particles.
On the other hand, when it is not possible to obtain a single magnetic particle, the magnetic particle is isolated and used as a sample according to a method for isolating the magnetic particle from the toner described below. Then, measurement and confirmation are performed in the same manner as described above.

<Measurement method of height of protrusion of magnetic particles>
The magnetic particles were observed with a transmission electron microscope (JEM-2100 manufactured by JEOL Ltd.), and the protruding height was measured with reference to the base surface of the octahedral plane. The size of the convex portion refers to a height that protrudes from the base surface of the coating layer when the coated magnetic particles are observed with a TEM. Then, as shown in FIG. 3, the height h from the base surface of the coating layer to the apex of the protrusion is measured for 15 or more protrusions in the randomly selected magnetic body, and the measured values are arithmetically averaged. .
On the other hand, when it is not possible to obtain a single magnetic particle, the magnetic particle is isolated and used as a sample according to a method for isolating the magnetic particle from the toner described below. Then, measurement and confirmation are performed in the same manner as described above.

<Method for confirming presence / absence of protrusions of magnetic particles>
The presence or absence of a convex portion on the surface of the magnetic particles was observed with a transmission electron microscope (JEM-2100 manufactured by JEOL Ltd.), and the height of the protruding portion was 1 nm based on the base surface of the octahedral flat portion. The above was regarded as a convex part, and the presence or absence thereof was confirmed.
On the other hand, when it is not possible to obtain a single magnetic particle, the magnetic particle is isolated and used as a sample according to a method for isolating the magnetic particle from the toner described below. Then, measurement and confirmation are performed in the same manner as described above.

<Method of measuring total pore volume of magnetic particles>
The pore volume of the magnetic particles is measured by a gas adsorption method using a pore distribution measuring device Tristar 3000 (manufactured by Shimadzu Corporation) to adsorb nitrogen gas on the sample surface.
Before the measurement of the pore distribution, 1-2 g of the sample is placed in a sample tube and evacuated at 100 ° C. for 24 hours. After evacuation, the sample weight is precisely weighed to obtain a sample. The obtained sample is used to determine the total pore volume in the range of pore diameter of 1.7 nm or more and 300.0 nm or less by the BJH desorption method using the above pore distribution measuring device. For the evaluation of the pore distribution, it is preferable to use the total pore volume closest to the measurement data information as an index.
On the other hand, when it is not possible to obtain a single magnetic particle, the magnetic particle is isolated and used as a sample according to a method for isolating the magnetic particle from the toner described below. Then, measurement and confirmation are performed in the same manner as described above.

<Method for separating magnetic particles from toner>
(1) 50 mg of toner and 20 mL of THF are weighed into a 50 mL vial, shaken sufficiently, and dissolved in THF until the sample is no longer united. The dissolution temperature is basically 25 ° C, and the dissolution is performed in the range of 25 to 50 ° C depending on the solubility of the sample.
(2) Next, a neodymium magnet (Model NE019, diameter × thickness φ22 mm × 10 mm, surface magnetic flux density: 450 mT) was applied from the outside of the vial to support the magnetic particles on the bottom surface of the vial, and the supernatant THF solution was used. And separated.
(3) Thereafter, 20 mL of THF was added to the vial, and the magnetic particles were washed by shaking again sufficiently. Then, a neodymium magnet was applied from the outside of the vial to support the magnetic particles on the bottom surface of the vial. Separated from the supernatant THF solution.
(4) The operation of (3) was repeated at least 100 times to sufficiently wash the magnetic particles.
(5) The magnetic particles were separated from the toner by drying the washed magnetic particles.

<Measurement of glass transition temperature Tg, peak endothermic peak temperature P (melting point), half width W1, and heat of fusion>
The glass transition temperature Tg, the peak temperature P of the endothermic peak, the half width W1, and the heat of fusion are measured using a differential scanning calorimeter "Q2000" (manufactured by TA Instruments) in accordance with ASTM D3418-82.
The temperature correction of the device detection unit uses the melting points of indium and zinc, and the heat quantity correction uses the heat of fusion of indium.
Specifically, about 2.0 mg of the sample was precisely weighed, placed in an aluminum pan, and an empty aluminum pan was used as a reference. The measurement is performed at a temperature rate of 10 ° C./min.
In the measurement, the sample is heated once to 200 ° C. at a rate of 10 ° C./min, then cooled to −10 ° C. at a rate of 10 ° C./min, and then heated again.
A specific heat change is obtained in the temperature range of 30 ° C. to 100 ° C. in the second heating process. The intersection between the line at the midpoint of the baseline before and after the specific heat change and the differential heat curve at this time was defined as the glass transition temperature Tg.
The temperature P at the top of the endothermic peak, the half width W1, and the amount of heat of fusion represent the maximum endothermic peak temperature of the endothermic peak appearing on the endothermic side with respect to the base line with respect to the differential heat curve in the second heating process. P and the half width of the endothermic peak was W1. Further, the heat of fusion was determined from the area of the endothermic peak.
On the other hand, when the crystalline material alone cannot be obtained, the crystalline material is isolated and used as a sample according to a method for separating the crystalline material from the toner described below. Then, measurement and confirmation are performed in the same manner as described above.

<Measurement of weight average molecular weight and ratio of molecular weight of 2000 or less by GPC>
The following equipment and conditions were used for the measurement.
Equipment: High-speed GPC "HLC8120 GPC" (manufactured by Tosoh Corporation)
Column: 7 columns of Shodex KF-801, 802, 803, 804, 805, 806, 807 (manufactured by Showa Denko KK)
Eluent: THF
Flow rate: 1.0 mL / min
Oven temperature: 40.0 ° C
Sample injection volume: 0.10 mL
In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the count value.
As a standard polystyrene sample for preparing a calibration curve, for example, a standard polystyrene sample having a molecular weight of about 10 ² to 10 ⁷ manufactured by Tosoh Corporation or Showa Denko KK is suitably used.
A sample is prepared as follows.
After the sample was placed in THF and allowed to stand for 5 hours, it was shaken sufficiently and dissolved in THF until the sample was no longer united. The dissolution temperature was basically 25 ° C., and was dissolved in the range of 25 to 50 ° C. depending on the solubility of the sample. Thereafter, it was further stored at 25 ° C. for 12 hours or more. At this time, the time of being left in THF is set to 24 hours. After that, a sample that has been passed through a sample processing filter (pore size of 0.2 μm or more and 0.5 μm or less, for example, Mishori Disc H-25-2 (manufactured by Tosoh Corporation) can be used as a GPC sample. The sample concentration was adjusted so that the resin component was 0.5 mg / ml or more and 5.0 mg / ml or less.
The area ratio of the molecular weight of 2000 or less in the molecular weight distribution chart of the tetrahydrofuran-soluble component of the toner was calculated as the ratio of the area of the molecular weight of 2000 or less to the entire area of the chart obtained in the above molecular weight measurement.

<Measurement of softening point>
The softening point is measured using a capillary rheometer of constant load extrusion type “Flow characteristic evaluation device Flow Tester CFT-500D” (manufactured by Shimadzu Corporation) according to the manual attached to the device. In this device, while applying a constant load with the piston from the top of the measurement sample, the measurement sample filled in the cylinder is heated and melted, and the melted measurement sample is pushed out from the die at the bottom of the cylinder, and the piston descends at this time. A flow curve showing the relationship between temperature and temperature can be obtained.
The "melting temperature in the 1/2 method" described in the manual attached to the "flow characteristic evaluation apparatus flow tester CFT-500D" is defined as the softening point. The melting temperature in the 1/2 method is calculated as follows. First, the difference between the piston descending amount Smax at the time when the outflow ends and the piston descending amount Smin at the time when the outflow starts is obtained (this is defined as X. X = (Smax−Smin) / 2). Then, the temperature of the flow curve when the amount of depression of the piston becomes the sum of X and Smin in the flow curve is the melting temperature in the 1/2 method.
The measurement sample was obtained by compressing about 1.0 g of the sample under an environment of 25 ° C. using a tablet molding compressor (for example, NT-100H, manufactured by NPA System) at about 10 MPa for about 60 seconds. A cylinder having a diameter of about 8 mm is used.
The measurement conditions of CFT-500D are as follows.
Test mode: Heating method Heating rate: 4 ° C / min
Starting temperature: 40 ° C
Ultimate temperature: 200 ° C
Piston cross-sectional area: 1.000cm ²
Test load (piston load): 10.0 kgf (0.9807 MPa)
Preheating time: 420 seconds Diameter of die hole: 1.0 mm
Die length: 1.0mm

<Measurement of acid value>
The acid value is the number of mg of potassium hydroxide required to neutralize the acid contained in 1 g of the sample. The acid value is measured according to JIS K 0070-1992. Specifically, the acid value is measured according to the following procedure.
(1) Preparation of Reagent A phenolphthalein solution is obtained by dissolving 1.0 g of phenolphthalein in 90 mL of ethyl alcohol (95 vol%) and adding ion-exchanged water to make 100 mL.
Dissolve 7 g of special grade potassium hydroxide in 5 mL of water and add ethyl alcohol (95 vol%) to make 1 L. After leaving the container in an alkali-resistant container for 3 days so as not to be exposed to carbon dioxide gas and the like, filtration is performed to obtain a potassium hydroxide solution. The obtained potassium hydroxide solution is stored in an alkali-resistant container. The factor of the potassium hydroxide solution is 0.1 mol / L hydrochloric acid 2
5 mL is placed in an Erlenmeyer flask, a few drops of the phenolphthalein solution is added, titrated with the potassium hydroxide solution, and determined from the amount of the potassium hydroxide solution required for neutralization. The 0.1 mol / L hydrochloric acid used is prepared according to JIS K 8001-1998.
(2) Operation (A) This test 2.0 g of the pulverized sample is precisely weighed in a 200 mL Erlenmeyer flask, and 100 mL of a mixed solution of toluene / ethanol (2: 1) is added thereto and dissolved for 5 hours. Next, several drops of the phenolphthalein solution are added as an indicator, and titration is performed using the potassium hydroxide solution. Note that the end point of the titration is when the light red color of the indicator continues for about 30 seconds.
(B) Blank test Titration is performed in the same manner as above except that no sample is used (that is, only a mixed solution of toluene / ethanol (2: 1) is used).
(3) The obtained result is substituted into the following equation to calculate the acid value.
A = [(CB) × f × 5.61] / S
Here, A: acid value (mgKOH / g), B: added amount of potassium hydroxide solution in blank test (mL), C: added amount of potassium hydroxide solution in main test (mL), f: potassium hydroxide Solution factor, S: Sample (g).

<Method of Measuring Weight Average Particle Size (D4) of Toner Particles>
The weight average particle diameter (D4) of the toner is calculated as follows. As a measuring device, a precise particle size distribution measuring device “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) equipped with a 100 μm aperture tube by a pore electric resistance method is used. For setting the measurement conditions and analyzing the measurement data, the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter) is used. The measurement is performed with 25,000 effective measurement channels.
As the electrolytic aqueous solution used for the measurement, a solution prepared by dissolving a special grade sodium chloride in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter) can be used.
Before the measurement and analysis, the dedicated software was set as follows.
On the “Change Standard Measurement Method (SOM)” screen of the dedicated software, set the total count number in the control mode to 50,000 particles, set the number of measurements to 1, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter Set the value obtained by using the following method. By pressing the “threshold / noise level measurement button”, the threshold and the noise level are automatically set. Also, the current is set to 1600 μA, the gain is set to 2, and the electrolytic solution is set to ISOTON II, and a check is made in “Flush aperture tube after measurement”.
On the “pulse to particle size conversion setting” screen of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set from 2 μm to 60 μm.
The specific measuring method is as follows.
(1) About 200 mL of the aqueous electrolytic solution is placed in a 250 mL round bottom beaker made of glass exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 revolutions / second. Then, the dirt and air bubbles in the aperture tube are removed by the “aperture flush” function of the dedicated software.
(2) About 30 mL of the electrolytic aqueous solution is placed in a 100 mL flat bottom glass beaker. As a dispersant, "Contaminone N" (trade name; 10% by mass aqueous solution of a neutral detergent for cleaning a precision measuring instrument having a pH of 7 comprising a nonionic surfactant, an anionic surfactant and an organic builder, Wako Pure Chemical Industries, Ltd.) (Manufactured by Kogyo Co., Ltd.) is diluted about 3 times by mass with ion-exchanged water, and about 0.3 mL of a diluent is added.
(3) An ultrasonic disperser “Ultrasonic Dispersion System Tetora 150” (trade name, manufactured by Nikkaki Bios Co., Ltd.) having two oscillators having an oscillation frequency of 50 kHz and having a phase difference of 180 degrees and having an electrical output of 120 W is prepared. I do. About 3.3 L of ion-exchanged water is put into the water tank of the ultrasonic disperser, and about 2 mL of 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. Then, the height position of the beaker is adjusted so that the resonance state of the liquid level of the aqueous electrolytic solution in the beaker becomes 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 little by little to the electrolytic aqueous solution and dispersed. Then, the ultrasonic dispersion processing is continued for another 60 seconds. The ultrasonic dispersion is appropriately adjusted so that the water temperature of the water tank is 10 ° C. or more and 40 ° C. or less.
(6) To the round bottom beaker of (1) installed in the sample stand, the electrolytic aqueous solution of (5) in which the toner is dispersed is dropped using a pipette, and the measured concentration is adjusted to about 5%. . Then, measurement is performed until the number of particles to be measured reaches 50,000.
(7) Analyze the measured data with the dedicated software attached to the device, and calculate the weight average particle size (D4). The “average diameter” on the “analysis / volume statistics (arithmetic average)” screen when the graph / volume% is set by the dedicated software is the weight average particle diameter (D4).

<Confirmation of presence / absence of bond between terminal of crystalline polyester resin and aliphatic monoalcohol or aliphatic monocarboxylic acid>
Using MALDI-TOFMS (Reflex III manufactured by Bruker Daltonics), the presence or absence of a bond between the terminal of the crystalline polyester resin and the aliphatic monoalcohol and / or aliphatic monocarboxylic acid was confirmed.
2 mg of a crystalline polyester resin sample was precisely weighed, and 2 mL of chloroform was added and dissolved to prepare a sample solution. A crystalline polyester resin, which is a raw material of the toner, is used as a sample. However, when a sample is difficult to obtain, a toner containing a resin sample can be used instead.
Next, 20 mg of 2,5-dihydroxybenzoic acid (DHBA) was precisely weighed and dissolved by adding 1 mL of chloroform to prepare a matrix solution.
Then, after accurately weighing 3 mg of sodium trifluoroacetate (NaTFA), 1 mL of acetone was added and dissolved to prepare an ionization aid solution.
25 μL of the sample solution thus prepared, 50 μL of the matrix solution, and 5 μL of the ionization aid solution were mixed, dropped on a sample plate for MALDI analysis, and dried to obtain a measurement sample.
In the obtained mass spectrum, each peak in the oligomer region (m / Z is 2000 or less) is assigned, and a peak corresponding to a composition in which an aliphatic monoalcohol or an aliphatic monocarboxylic acid is bonded to a molecular terminal is present. No was confirmed, and the presence or absence of binding was determined.
On the other hand, when the crystalline polyester resin alone cannot be obtained, the crystalline polyester resin is isolated and used as a sample according to a method for separating a crystalline material from a toner described below. Then, measurement and confirmation are performed in the same manner as described above.

<Method of separating crystalline material from toner>
(1) 50 mg of toner and 20 mL of THF are weighed into a 50 mL vial, shaken sufficiently, and dissolved in THF until the sample is no longer united. The dissolution temperature is 25 ° C. (2) Next, a neodymium magnet (Model NE019, diameter × thickness φ22 mm × 10 mm, surface magnetic flux density: 450 mT) was applied from the outside of the vial to support the magnetic particles on the bottom surface of the vial, and the supernatant THF solution was used. And separated.
(3) The supernatant was used as filter paper No. The solution is subjected to a total filtration using 5C. Thereafter, the THF-insoluble component is further washed three times with THF.
(4) The insoluble components on the filter paper are collected, and the cylindrical filter paper (for example, No. 86R size 28 × 10 mm
Into a Soxhlet extractor. The toluene-soluble matter is extracted for 16 hours using 200 ml of toluene as a solvent. At this time, extraction is performed at a reflux rate such that the extraction cycle of toluene is about once every 4 to 5 minutes. After completion of the extraction, a toluene solution is secured and left at room temperature for 24 hours.
(5) After 24 hours, the precipitated crystalline material component was filtered using a filter paper No. Separate using 5C to separate the crystalline material from the toner.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Unless otherwise specified, all parts and percentages in Examples and Comparative Examples are based on mass.

<Example A>
<Production example of binder resin 1>
In a reaction vessel equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, raw material monomers having the compounding amounts (molar ratios) shown in Table 1 were added. 1.0 part by mass was added. Then, the temperature in the tank was increased while stirring at 140 ° C. in a nitrogen atmosphere.
Thereafter, water was distilled off while heating at a heating rate of 10 ° C./hour from 140 ° C. to 200 ° C. with stirring to perform polycondensation. After the temperature reached 200 ° C., the pressure inside the reaction vessel was reduced to 5 kPa or less, polycondensation was performed at 200 ° C. for 6 hours under the conditions of 5 kPa or less, and the resin was cooled and pulverized to produce Binder Resin 1. Table 1 shows properties of the obtained binder resin 1.

<Production example of crystalline polyester resin 1>
In a reaction vessel equipped with a nitrogen inlet tube, a dehydration tube, a stirrer and a thermocouple, 1,12-dodecanediol as an aliphatic diol monomer and 1,10-decanediacid as an aliphatic dicarboxylic acid monomer are shown in Table 2. The amounts indicated were used.
Then, tin dioctylate was added as a catalyst in an amount of 1 part by mass based on 100 parts by mass of the total amount of monomers, and the mixture was heated at 150 ° C. in a nitrogen atmosphere and reacted for 5 hours while distilling off water under normal pressure.
Next, the reaction was carried out while increasing the temperature to 200 ° C. at a rate of 10 ° C./hour. After the temperature reached 200 ° C., the reaction was carried out for 2 hours.
Thereafter, the pressure in the reaction tank was gradually released, and the pressure was returned to normal pressure. After sampling, n-octadecanoic acid (18 carbon atoms) shown in Table 2 was added, and the reaction was performed at 200 ° C. for 2 hours under normal pressure. Was. The acid value of the sampled resin was 2 mgKOH / g. Thereafter, the pressure inside the reaction vessel was again reduced to 5 kPa or less at 200 ° C., and the reaction was carried out at 200 ° C. for 3 hours to obtain a crystalline polyester resin 1. Table 3 shows properties of the obtained crystalline polyester resin 1.
In the MALDI-TOFMS mass spectrum of the obtained crystalline polyester resin 1, a peak having a composition in which n-octadecanoic acid was bonded to the molecular terminal of the crystalline polyester resin 1 was confirmed. Further, the obtained crystalline polyester resin 1 showed a clear melting point.

表中、括弧内の記載は、アルコール又はカルボン酸の炭素数を示す。

In the table, the description in parentheses indicates the carbon number of the alcohol or carboxylic acid.

表中、ΔＨは、融解熱量を示す。

In the table, ΔH indicates the heat of fusion.

<Production Examples of Crystalline Polyester Resins 2 to 13>
Crystalline polyester resins 2 to 13 were obtained in the same manner as in Production Example of crystalline polyester resin 1 except that the monomer constitution was changed as shown in Table 2. Table 3 shows various physical properties.
From the MALDI-TOFMS mass spectrum of the crystalline polyester resins 2 to 4, the units derived from the aliphatic monoalcohol or aliphatic monocarboxylic acid shown in Table 2 were present at the molecular terminals of the crystalline polyester resins 2 to 4. The binding was confirmed. Further, the obtained crystalline polyester resin had a distinct melting point.

<Production Example of Magnetic Particle A1>
(1) Production of Core Particles 92 L of an aqueous ferrous sulfate solution having an Fe ²⁺ concentration of 1.79 mol / L and 88 L of an aqueous sodium hydroxide solution having a 3.74 mol / L were added and stirred. The pH of this solution was 6.5.
While maintaining this solution at a temperature of 89 ° C. and a pH of 9 to 12, air at 20 L / min was blown therein to cause an oxidation reaction to generate core particles. When the ferrous hydroxide was completely consumed, the blowing of air was stopped to terminate the oxidation reaction. The obtained magnetite core particles had an octahedral shape.
(2) Formation of coating layer After mixing 2 L of 0.7 mol / L sodium silicate aqueous solution and 2 L of 0.9 mol / L ferrous sulfate aqueous solution, 1 L of water was added to make 5 L of aqueous solution, and 13500 g of core particles Was added to the slurry after the reaction, while maintaining pH 7 to 9. Thereafter, air at 10 L / min was blown until Fe ²⁺ in the slurry did not remain.
Subsequently, after mixing 2 L of 1.5 mol / L aluminum sulfate aqueous solution and 2 L of 0.9 mol / L ferrous sulfate aqueous solution, 1 L of water was added to make 5 L of aqueous solution. -9 was maintained. Thereafter, air at 10 L / min was blown until Fe ²⁺ in the slurry did not remain. The temperature of the slurry was maintained at 89 ° C. After mixing and stirring for 30 minutes, the slurry was filtered, washed and dried to obtain magnetic particles A1.
The shape of the magnetic particles A1 was octahedral, had a convex portion with a height of 10.3 nm, the number average particle size of the primary particles was 120 nm, and the total pore volume was 0.069 cm ³ / g.
Table 4 shows conditions of the coating layer of the magnetic particles A1, and Table 5 shows properties of the magnetic particles A1.

<Production Example of Magnetic Particles A2 to A14>
The core particles were prepared in the same manner as in the method for producing the magnetic particles A1, except that the production conditions of the core particles were appropriately adjusted so that the number average particle diameter and the shape of the primary particles of the obtained magnetic particles had the values shown in Table 5. Obtained.
Thereafter, a coating layer was formed under the conditions shown in Table 4 to obtain magnetic particles A2 to A14. Table 5 shows various physical properties.

<Production Example of Toner A1>
Binder resin 1 100.0 parts by mass Crystalline polyester resin 1 1.0 parts by mass Magnetic particles A1 60.0 parts by mass )
2.0 parts by mass, charge control agent (T-77: manufactured by Hodogaya Chemical Co., Ltd.) 2.0 parts by mass The above materials are premixed with a Mitsui Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.) and then biaxial kneading extruder. Was melt-kneaded.
The obtained kneaded material was cooled, coarsely pulverized by a hammer mill, and then pulverized by a mechanical pulverizer (T-250 manufactured by Turbo Kogyo KK). The obtained finely pulverized powder was classified using a multi-segment classifier utilizing the Coanda effect to obtain negatively chargeable raw toner particles having a weight average particle diameter (D4) of 7.0 μm.
The raw toner particles were subjected to a surface modification treatment with a surface modification device Faculty (manufactured by Hosokawa Micron Corporation). At that time, the rotational peripheral speed of the dispersion rotor was set to 150 m / sec, the input amount of the finely pulverized product was set to 7.6 kg per cycle, and the surface modification time (= cycle time, the discharge valve was opened after the raw material supply was completed) The time until the start) was set to 82 sec. The temperature at the time of discharging the toner particles was 44 ° C. Through the above steps, toner particles A1 were obtained.
Using a Mitsui Henschel mixer (Model FM-10, processing volume: 10 L, manufactured by Mitsui Miike Kakoki Co., Ltd.), 100.0 parts of toner particles A1 were added to hydrophobic silica fine powder surface-treated with hexamethyldisilazane ( 1.3 parts of primary particle number average particle diameter: 10 nm, original silica BET specific surface area: 200 m ² / g) were added. These were mixed with a Mitsui Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.) at 3200 rpm for 3 minutes and sieved with a sieve having a mesh size of 75 μm (# 200) to obtain a toner A1. The formulations are shown in Table 6.

<Production Examples of Toners A2 to A26>
Toners A2 to A26 were obtained in the same manner as in Toner A1 except that the toner formulation was changed as shown in Table 6 in Production Example of Toner 1.

<Examples A1 to A19, Comparative Examples A1 to A7>
The toner A1 was evaluated as follows. Table 7 shows the evaluation results. Further, the toners A2 to A26 were similarly evaluated.

<Low-temperature fixability (decrease rate of rubbing density before leaving)>
The low-temperature fixing property was modified such that the fixing device of a laser beam printer (HP LaserJet Enterprise 600 M603) manufactured by Hewlett-Packard Company was taken out, the temperature of the fixing device could be set arbitrarily, and the process speed became 550 mm / sec. An external fixing device was used.
Using the above-described apparatus, an unfixed image was passed through a fixing device adjusted to 160 ° C. in a normal temperature and normal humidity environment (temperature: 23.5 ° C., humidity: 60% RH). At this time, the amount of applied toner on the unfixed image was adjusted so that the image density of the fixed image was 0.67 to 0.73. The recording medium used was “prober bond paper” (105 g / m ² , manufactured by Fox River). The obtained fixed image was rubbed with a silbon paper under a load of 4.9 kPa (50 g / cm ² ), and the reduction rate of image density before and after rubbing (rubbing density reduction rate [%]) was determined. The evaluation was based on the following criteria.
The image density was measured using a Macbeth densitometer (manufactured by Macbeth) as a reflection densitometer using an SPI filter.
A: Rubbing density reduction rate is less than 5.0%.
B: The rubbing density reduction rate is 5.0% or more and less than 10.0%.
C: The reduction rate of the rubbing density is 10.0% or more and less than 20.0%.
D: Rubbing density reduction rate is 20.0% or more.
In the present invention, C or more is acceptable.

<Gloss unevenness evaluation>
In the same manner as in the low-temperature fixability test, 10 sheets were output in a low-temperature and low-humidity environment (temperature: 15.0 ° C., humidity: 5% RH), and images were confirmed using a 25-fold loupe. The evaluation paper used was PB PAPER (manufactured by Canon Marketing Japan Inc., basis weight 66 g / m ² , letter).
Ten images were confirmed, the number of unevenness was counted, and gloss unevenness was evaluated.
A: No occurrence
B: 1 or more, 2 or less C: 3 or more, 5 or less D: 6 or more

<Change in fixability before and after standing>
The fixed image obtained in the same manner as in the low-temperature fixing property test was taken out after leaving the fixed image in a high-temperature and high-humidity environment (temperature: 40 ° C., humidity: 95% RH) for 30 days, and taken out under a normal temperature and normal humidity environment (temperature: 23.5). C. and humidity of 60% RH) for 1 day to obtain a fixed image 1 after the standing.
Then, the fixed image 1 after leaving was rubbed with a silbon paper under a load of 4.9 kPa (50 g / cm ² ), and the rate of decrease in image density before and after rubbing was measured. The rate [%] was measured. Then, the difference between the rubbing density reduction rate (A [%]) of the image before leaving and the rubbing density reduction rate (B [%]) of the image after leaving is determined by a change in fixability before and after leaving (C [%]). And evaluated according to the following criteria.
A: Change in fixability before and after standing is less than 5.0%.
B: Change in fixability before and after standing is 5.0% or more and less than 10.0%.
C: Change in fixability before and after standing is 10.0% or more and less than 15.0%.
D: Change in fixability before and after standing is 15.0% or more.
In the present invention, C or more is acceptable.

<Curl of left image>
The fixing unit of the laser beam printer (HP LaserJet Enterprise 600 M603) manufactured by Hewlett-Packard Company is taken out, the temperature of the fixing unit can be set arbitrarily, and an external fixing unit modified so that the process speed becomes 550 mm / sec is used. Was.
Using the above device, under normal temperature and normal humidity environment (temperature 23.5 ° C, humidity 60% RH), 50 sheets of solid image with 100% printing ratio on the front side and 50% vertical line image with 5% printing ratio on the back side Output and sampled the 50th image.
As this evaluation paper, PB PAPER (manufactured by Canon Marketing Japan Inc., basis weight 66 g / cm ² , letter) was used.
The obtained fixed image is taken out after leaving the fixed image in a high-temperature and high-humidity environment (temperature: 40 ° C., humidity: 95% RH) for 30 days, and taken out under a normal temperature and normal humidity environment (temperature: 23.5 ° C., humidity: 60% RH). For one day to obtain a fixed image 2 after the standing.
Then, the left-fixed image 2 is raised on a flat surface with the surface image facing upward, and the average value of the three points of the distance between the leading end of the paper and the flat surface is measured. The curl was evaluated.
A: The distance between the paper edge and the plane is less than 2.0 mm.
B: The distance between the paper edge and the plane is 2.0 mm or more and less than 5.0 mm.
C: The distance between the paper edge and the plane is not less than 5.0 mm and less than 10.0 mm.
D: The distance between the paper edge and the plane is 10.0 mm or more.
In the present invention, C or more is acceptable.

<Example B>
<Binder resin 1>
Binder resin 1 was produced in the same manner as described above.

<Example of manufacturing crystalline material 1>
In a reaction vessel equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, Table 12 shows 1,12-dodecanediol as an aliphatic diol monomer and 1,10-decanediacid as an aliphatic dicarboxylic acid monomer. The amounts indicated were used.
Then, tin dioctylate was added as a catalyst in an amount of 1 part by mass based on 100 parts by mass of the total amount of monomers, and the mixture was heated at 150 ° C. in a nitrogen atmosphere and reacted for 5 hours while distilling off water under normal pressure.
Next, the reaction was carried out while increasing the temperature to 200 ° C. at a rate of 10 ° C./hour. After the temperature reached 200 ° C., the reaction was carried out for 2 hours.
Thereafter, the pressure in the reaction tank was gradually released, and the pressure was returned to normal pressure. After sampling, n-octadecanoic acid (18 carbon atoms) shown in Table 2 was added, and the reaction was performed at 200 ° C. for 2 hours under normal pressure. Was. The acid value of the sampled resin was 2. Thereafter, the pressure inside the reaction vessel was again reduced to 5 kPa or less at 200 ° C., and the reaction was performed at 200 ° C. for 3 hours to obtain a crystalline material 1. Table 9 shows properties of the obtained crystalline material 1.
In the MALDI-TOFMS mass spectrum of the obtained crystalline material 1, a peak having a composition in which n-octadecanoic acid was bonded to the molecular terminal of the crystalline polyester resin was confirmed.

<Examples of production of crystalline materials 2 to 4>
Crystalline materials 2 to 4 were obtained in the same manner as in the production example of the crystalline material 1 except that the monomer configuration was changed as shown in Table 8 in the production example of the crystalline material 1. Table 9 shows various physical properties.
From the MALDI-TOFMS mass spectrum of the crystalline polyester resins B2 to B3, a unit derived from an aliphatic monoalcohol or an aliphatic monocarboxylic acid shown in Table 8 was added to the molecular terminals of the crystalline polyester resins B2 to B3. Were confirmed to be bonded. In addition, the crystalline materials 1 to 4 had clear melting points.

<Production Examples of Crystalline Materials 5 to 13>
The crystalline materials 5 to 13 were produced by purifying raw material waxes (paraffin wax, Fischer-Tropsch wax, polyethylene wax, and polypropylene wax) shown in Table 8 by a method such as vacuum distillation and fractional crystallization. Table 9 shows various physical properties.

表中、ΔＨは、融解熱量を示す。

In the table, ΔH indicates the heat of fusion.

<Production Example of Magnetic Particle B1>
(1) Production of Core Particles 92 L of an aqueous ferrous sulfate solution having an Fe ²⁺ concentration of 1.79 mol / L and 88 L of an aqueous sodium hydroxide solution having a 3.74 mol / L were added and stirred. The pH of this solution was 6.5.
While maintaining this solution at a temperature of 89 ° C. and a pH of 9 to 12, air at 20 L / min was blown therein to cause an oxidation reaction to generate core particles. When the ferrous hydroxide was completely consumed, the blowing of air was stopped to terminate the oxidation reaction. The obtained magnetite core particles had an octahedral shape.
(2) Formation of coating layer After mixing 2 L of 0.7 mol / L sodium silicate aqueous solution and 2 L of 0.9 mol / L ferrous sulfate aqueous solution, 1 L of water was added to make 5 L of aqueous solution, and 13500 g of core particles Was added to the slurry after the reaction, while maintaining pH 7 to 9. Thereafter, air at 10 L / min was blown until Fe ²⁺ in the slurry did not remain.
Subsequently, after mixing 2 L of 1.5 mol / L aluminum sulfate aqueous solution and 2 L of 0.9 mol / L ferrous sulfate aqueous solution, 1 L of water was added to make 5 L of aqueous solution. -9 was maintained. Thereafter, air at 10 L / min was blown until Fe ²⁺ in the slurry did not remain. The temperature of the slurry was maintained at 89 ° C. After mixing and stirring for 30 minutes, the slurry was filtered, washed and dried to obtain magnetic particles B1.
The shape of the magnetic particles B1 was octahedron, had a projection with a height of 10.3 nm, the number average particle size of the primary particles was 120 nm, and the total pore volume was 0.069 cm ³ / g.
Table 10 shows the conditions of the coating layer of the magnetic particles B1 and Table 11 shows various physical properties.

<Production Example of Magnetic Particles B2 to B12>
The core particles were prepared in the same manner as in the method for producing the magnetic particles B1, except that the production conditions of the core particles were appropriately adjusted such that the number average particle diameter and the shape of the primary particles of the obtained magnetic particles had the values shown in Table 11. Obtained.
Thereafter, a coating layer was formed under the conditions shown in Table 10 to obtain magnetic particles B2 to B12. Table 11 shows various physical properties.

<Production Example of Toner B1>
100.0 parts by mass of binder resin 1 1.0 part by mass of crystalline material 1 2.0 parts by mass of crystalline material 5 60.0 parts by mass of magnetic particles B1 Charge control agent (T-77: Hodogaya Chemical 2.0 parts by mass The above materials were pre-mixed with a Henschel mixer, and then melt-kneaded with a twin-screw kneading extruder.
The obtained kneaded material was cooled, coarsely pulverized by a hammer mill, and then pulverized by a mechanical pulverizer (T-250 manufactured by Turbo Kogyo KK). The obtained finely pulverized powder was classified using a multi-segment classifier utilizing the Coanda effect to obtain negatively chargeable raw toner particles having a weight average particle diameter (D4) of 7.0 μm.
The raw toner particles were subjected to a surface modification treatment with a surface modification device Faculty (manufactured by Hosokawa Micron Corporation). At that time, the rotational peripheral speed of the dispersion rotor was set to 150 m / sec, the input amount of the finely pulverized product was set to 7.6 kg per cycle, and the surface modification time (= cycle time, the discharge valve was opened after the raw material supply was completed) The time until the start) was set to 82 sec. The temperature at the time of discharging the toner particles was 44 ° C. Through the above steps, toner particles B1 were obtained.
Using a Henschel mixer (Model FM-10, processing volume 10 L, manufactured by Mitsui Mining Co., Ltd.), 100.0 parts of the toner particles B1 were added to hydrophobic silica fine powder surface-treated with hexamethyldisilazane (the number of primary particles). Average particle diameter: 10 nm, 1.3 parts of original silica BET specific surface area: 200 m ² / g) were added. These were mixed with a Henschel mixer at 3200 rpm for 3 minutes, and sieved with a sieve having openings of 75 μm (# 200) to obtain a toner B1.

<Production Examples of Toners B2 to B19>
In the production example of the toner B1, toners B2 to B19 were obtained in the same manner as the toner B1, except that the toner formulation was changed as shown in Table 12.

表中、融点差は、「結晶性材料Ｂの融点（Ｍｂ）−結晶性材料Ａの融点（Ｍａ）」の値を示す。また、個数平均粒径の単位はｎｍである。

In the table, the melting point difference indicates a value of “melting point of crystalline material B (Mb) −melting point of crystalline material A (Ma)”. The unit of the number average particle size is nm.

<Example B1>
The toner B1 was evaluated as follows. Table 13 shows the evaluation results. Similarly, the toners B2 to B19 were evaluated.

<Low-temperature fixability (decrease rate of rubbing density before leaving)>
The low-temperature fixability was evaluated in the same manner as described above.

<Gloss unevenness evaluation>
Gloss unevenness was evaluated in the same manner as described above.

<Cardboard offset test>
In the thick paper offset test, a fixing device of a laser beam printer (HP LaserJet Enterprise 600 M603) manufactured by Hewlett-Packard Company was taken out, the temperature of the fixing device could be set arbitrarily, and the process speed was changed to 250 mm / sec. An external fixing device was used.
Using the above apparatus, in a normal temperature and normal humidity environment (temperature: 23.5 ° C., humidity: 60% RH), after passing 10 solid black images through a fixing device adjusted to 160 ° C., one solid white image is printed. Output. In addition, laser copier paper (GF-C209 A4 paper manufactured by Canon, basis weight 209 g / m ² ) was used as a recording medium.
The number of spots on the solid white image was counted and evaluated as a thick paper offset test.
A: No occurrence B: 1 or more and 2 or less C: 3 or more and 5 or less D: 6 or more

<Change in fixability before and after standing>
The change in fixability before and after standing was evaluated in the same manner as described above.

<Curl of left image>
The curl of the image after standing was evaluated in the same manner as above.

<Example C>
<Binder resin 1>
Binder resin 1 was produced in the same manner as described above.

<Example of wax production>
Raw material waxes (paraffin wax, Fischer-Tropsch wax, polyethylene wax, polypropylene wax) shown in Table 14 were purified by a method such as vacuum distillation and fractional crystallization.

<Production Example of Magnetic Particle C1>
(1) Production of Core Particles 92 L of an aqueous ferrous sulfate solution having an Fe ²⁺ concentration of 1.79 mol / L and 88 L of an aqueous sodium hydroxide solution having a 3.74 mol / L were added and stirred. The pH of this solution was 6.5.
While maintaining this solution at a temperature of 89 ° C. and a pH of 9 to 12, air at 20 L / min was blown therein to cause an oxidation reaction to generate core particles. When the ferrous hydroxide was completely consumed, the blowing of air was stopped to terminate the oxidation reaction. The obtained magnetite core particles had an octahedral shape.
(2) Formation of coating layer After mixing 2 L of 0.7 mol / L sodium silicate aqueous solution and 2 L of 0.9 mol / L ferrous sulfate aqueous solution, 1 L of water was added to make 5 L of aqueous solution, and 13500 g of core particles Was added to the slurry after the reaction, while maintaining pH 7 to 9. Thereafter, air at 10 L / min was blown until Fe ²⁺ in the slurry did not remain.
Subsequently, after mixing 2 L of 1.5 mol / L aluminum sulfate aqueous solution and 2 L of 0.9 mol / L ferrous sulfate aqueous solution, 1 L of water was added to make 5 L of aqueous solution. -9 was maintained. Thereafter, air at 10 L / min was blown until Fe ²⁺ in the slurry did not remain. The temperature of the slurry was maintained at 89 ° C. After mixing and stirring for 30 minutes, the slurry was filtered, washed and dried to obtain magnetic particles C1.
The shape of the magnetic particles C1 was octahedral, had a projection with a height of 10.3 nm, the number average particle size of the primary particles was 120 nm, and the total pore volume was 0.069 cm ³ / g.
Table 16 shows the coating layer conditions of the magnetic particles C1, and Table 15 shows various physical properties.

<Production Example of Magnetic Particles C2 to C13>
The core particles were prepared in the same manner as the method for producing the magnetic particles C1, except that the production conditions of the core particles were appropriately adjusted so that the number average particle diameter and the shape of the primary particles of the obtained magnetic particles had the values shown in Table 15. Obtained.
Thereafter, a coating layer was formed under the conditions shown in Table 16 to obtain magnetic particles C2 to C13. Table 15 shows the physical properties.

<Production Example of Toner C1>
-100.0 parts by mass of binder resin 1-2.0 parts by mass of wax 1-60.0 parts by mass of magnetic particles C1-2.0 parts by mass of charge control agent (T-77: manufactured by Hodogaya Chemical Co., Ltd.) After pre-mixing with a mixer, the mixture was melt-kneaded by a twin-screw kneading extruder.
After cooling the obtained kneaded material and coarsely pulverizing it with a hammer mill, a mechanical pulverizer (Turbo Kogyo (
(T-250). The obtained finely pulverized powder was classified using a multi-segment classifier utilizing the Coanda effect to obtain negatively chargeable raw toner particles having a weight average particle diameter (D4) of 7.0 μm.
The raw toner particles were subjected to a surface modification treatment with a surface modification device Faculty (manufactured by Hosokawa Micron Corporation). At that time, the rotational peripheral speed of the dispersion rotor was set to 150 m / sec, the input amount of the finely pulverized product was set to 7.6 kg per cycle, and the surface modification time (= cycle time, the discharge valve was opened after the raw material supply was completed) The time until the start) was set to 82 sec. The temperature at the time of discharging the toner particles was 44 ° C. Through the above steps, toner particles C1 were obtained.
Using a Henschel mixer (Model FM-10, processing volume: 10 L, manufactured by Mitsui Mining Co., Ltd.), 100.0 parts of toner particles C1 were added to hydrophobic silica fine powder surface-treated with hexamethyldisilazane (the number of primary particles). Average particle diameter: 10 nm, 1.3 parts of original silica BET specific surface area: 200 m ² / g) were added. These were mixed with a Henschel mixer at 3200 rpm for 3 minutes, and sieved with a sieve having openings of 75 μm (# 200) to obtain a toner C1.

<Production Examples of Toners C2 to C18>
Toners C2 to C18 were obtained in the same manner as in Production Example of Toner C1, except that the toner formulation was changed as shown in Table 17.

<Example C1>
The toner C1 was evaluated as follows. Table 18 shows the evaluation results. In the same manner, the toners C2 to C18 were evaluated.

<Gloss unevenness evaluation>
Gloss unevenness was evaluated in the same manner as described above.

<Low-temperature fixability (decrease rate of rubbing density before leaving)>
The low-temperature fixability was evaluated in the same manner as described above.

<Cardboard offset test>
The thick paper offset test was evaluated in the same manner as described above.

<Change in fixability before and after standing>
Changes in fixability before and after standing were also evaluated in the same manner as above.

<Curl of left image>
The curl of the image after standing was evaluated in the same manner as above.

Claims (7)

A toner having toner particles containing a binder resin, a crystalline material A, and magnetic particles,
The crystalline material A is a crystalline polyester resin having a unit derived from an aliphatic diol and a unit derived from an aliphatic dicarboxylic acid,
The toner, wherein the magnetic particles satisfy all of the following requirements (i) to (iii).
(I) having an octahedral shape, a core having magnetite particles having a convex portion on a plane portion of the octahedron, and (ii) having a coating layer provided on the surface of the core. (Iii) the coating layer is in addition to the oxide containing iron, it contains an oxide containing an oxide and aluminum containing silicon   The toner according to claim 1, wherein the number average particle diameter of the primary particles of the magnetic particles is 50 nm or more and 200 nm or less. The toner according to claim 1, wherein a total pore volume of the magnetic particles is 0.060 cm ³ / g or more and 0.150 cm ³ / g or less. Among the units derived from the aliphatic diol, the proportion of units derived from an aliphatic diol having 6 to 12 carbon atoms is 85 mol% or more,
The toner according to any one of claims 1 to 3 , wherein a proportion of a unit derived from an aliphatic dicarboxylic acid having 6 to 12 carbon atoms among units derived from the aliphatic dicarboxylic acid is 85 mol% or more. The toner particles further contain a crystalline material B,
The melting point of the crystalline polyester resin Ma (° C.), when the melting point of the crystalline material B Mb and (° C.), according to any one of claims 1 to 4, satisfying the following formula (1) Toner.
5 ≦ Mb−Ma ≦ 50 (1) The toner according to claim 5 , wherein the crystalline material B is a hydrocarbon wax. In the chart of the molecular weight distribution of the tetrahydrofuran soluble component of the toner measured by gel permeation chromatography, the area ratio of the molecular weight of 2000 or less is 5.0 area% or less with respect to the entire area of the chart. the toner according to any one of claims 1 to 6.

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