JP7233922B2 - Toner and toner manufacturing method - Google Patents

Description

The present invention relates to a toner and a method for producing the toner used in electrophotography, electrostatic recording, and electrostatic printing.

In recent years, with the widespread use of electrophotographic full-color copiers, there is a demand for higher speeds and higher image quality. For high image quality, it is necessary to improve the developability and transferability of the toner. In addition, there is a demand for high-speed copying machines and stable output images, and the development of toners with higher stress resistance than ever before is required.

In order to obtain stable performance of the toner, the toner particles contain an inorganic fine particle powder such as a metal oxide, which is a so-called external additive. Furthermore, it is known that these inorganic fine particle powders have the effect of improving the fluidity of the toner and the effect of reducing the adhesion of the toner by acting as spacers between toner particles or between toner particles and other members. However, it is also known that these inorganic fine particles are detached from the toner surface and their functions are lowered, so it is important not to detach them from the toner surface.

In order to obtain excellent fluidity and transferability without detaching inorganic fine particles from the toner surface, small and large silica particles are attached to the surface of the toner base particles and fixed by impact force. There has been proposed a toner that has a In this case, although there is a certain effect in improving the initial transferability, there is no mention of the transferability after applying stress or the fluidity of the toner and developer, and there is room for further improvement in this respect.

Further, in order to improve stress resistance, a toner has been proposed in which the following two types of silica are added to 100 parts by weight of toner base particles, and then heat-treated to make the toner spherical (Patent Document 2).
0.5 parts by mass or more and 6.0 parts by weight or less of silica having a number average particle size of primary particles of 35 nm or more and 300 nm or less - 0.1 parts by mass or more of silica having a number average particle size of primary particles of 4 nm or more and 30 nm or less3. 0 parts by weight or less In this case, a certain effect is seen in the stress resistance of the toner, but there is still room for improvement in order to cope with further speeding up and two-component development methods that place more stress on the toner. There is

Also, in order to obtain high-quality images, so-called image defects due to poor cleaning or the like should not occur. The direction of improving the above-mentioned transferability is the direction of decreasing the residual toner after transfer. As a means of improving the transferability, there is a means of increasing the circularity of the toner, but this is also a direction in which the cleaning performance becomes severe, as has been conventionally said. As described above, transferability and cleaning property often have a trade-off relationship.

JP 2011-186402 A JP 2007-279239 A

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner that achieves both excellent transferability and cleanability even when used for a long period of time.

According to the present invention, the toner includes toner particles containing a binder resin and a colorant, and inorganic fine particles coating the toner particles,
In the number distribution of the particle size of the primary particles of the inorganic fine particles on the surface of the toner particles,
A ₁ is the number of inorganic fine particles having a particle size in the range of 5 nm or more and 200 nm or less,
B ₁ is the number of inorganic fine particles present in a particle size range of 5 nm or more and 20 nm or less,
C ₁ is the number of inorganic fine particles having a particle diameter in the range of 35 nm or more and 55 nm or less,
When _D1 is the number of inorganic fine particles having a particle diameter in the range of 80 nm to 135 nm, the relationships of the following formulas (1) to (5) are satisfied,
0.95≦A ₁ /Number of all inorganic fine particles Equation (1)
0.20≦B ₁ /A ₁ ≦0.50 Formula (2)
0.15≦C ₁ /A ₁ ≦0.55 Formula (3)
0.15≦D ₁ /A ₁ ≦0.55 Formula (4)
0.70≦(B ₁ /A ₁ +C ₁ /A ₁ +D ₁ /A ₁ ) Equation (5)
a coverage of the inorganic fine particles with respect to the toner particles is 55% or more;
In the number distribution of the particle size of the primary particles of the inorganic fine particles on the surface of the toner particles after the toner is washed with water,
A ₂ is the number of inorganic fine particles having a particle diameter in the range of 5 nm or more and 200 nm or less,
B ₂ is the number of inorganic fine particles having a particle size in the range of 5 nm or more and 20 nm or less,
C ₂ is the number of inorganic fine particles having a particle diameter in the range of 35 nm or more and 55 nm or less,
When the number of inorganic fine particles present in the range of 80 nm or more and 135 nm or less in particle size is defined as _D2 , the relationships of the following formulas (6) to (8) are satisfied,
B ₂ /B ₁ ≦0.5 Formula (6)
0.85≦C ₂ /C ₁ formula (7)
0.55≦D ₂ /D ₁ ≦0.75 Formula (8)
In the water washing treatment, a dispersion of the toner added to deionized water containing a surfactant is shaken for 5 minutes under conditions of a shaking speed of 46.7 cm/sec and a shaking width of 4.0 cm. A toner is provided that is a

According to the present invention, it is possible to provide a toner that achieves both high levels of transferability and cleanability.

1 is a diagram of a thermal spheronization apparatus used for manufacturing toner according to the present invention; FIG. FIG. 4 is a diagram for explaining the action of an external additive in a cleaning process; FIG. 3 is a diagram showing an equivalent circuit between a charging roller and a photoreceptor; 4 is a diagram showing the relationship between an applied AC voltage Vac (maximum amplitude value; Vpp) and a charging AC current Iac; FIG.

As a result of extensive studies, the inventors of the present invention have found that the following is important for achieving both excellent transferability and cleanability, and have completed the present invention.
That is, the surfaces of the toner particles are coated with inorganic fine particles at a certain ratio or more, and the inorganic fine particles present on the surfaces of the toner particles exist at a certain ratio or more in each of three different particle diameter ranges.

That is, the toner according to the present invention is a toner having toner particles containing a binder resin and a colorant, and inorganic fine particles coating the toner particles,
In the number distribution of the particle size of the primary particles of the inorganic fine particles on the surface of the toner particles,
A ₁ is the number of inorganic fine particles having a particle size in the range of 5 nm or more and 200 nm or less,
B ₁ is the number of inorganic fine particles present in a particle size range of 5 nm or more and 20 nm or less,
C ₁ is the number of inorganic fine particles having a particle diameter in the range of 35 nm or more and 55 nm or less,
When _D1 is the number of inorganic fine particles having a particle diameter in the range of 80 nm to 135 nm, the relationships of the following formulas (1) to (5) are satisfied,
0.95≦A ₁ /Number of all inorganic fine particles Equation (1)
0.20≦B ₁ /A ₁ ≦0.50 Formula (2)
0.15≦C ₁ /A ₁ ≦0.55 Formula (3)
0.15≦D ₁ /A ₁ ≦0.55 Formula (4)
0.70≦(B ₁ /A ₁ +C ₁ /A ₁ +D ₁ /A ₁ ) Equation (5)
a coverage of the inorganic fine particles with respect to the toner particles is 55% or more;
In the number distribution of the particle size of the primary particles of the inorganic fine particles on the surface of the toner particles after the toner is washed with water,
A ₂ is the number of inorganic fine particles having a particle diameter in the range of 5 nm or more and 200 nm or less,
B ₂ is the number of inorganic fine particles having a particle size in the range of 5 nm or more and 20 nm or less,
C ₂ is the number of inorganic fine particles having a particle diameter in the range of 35 nm or more and 55 nm or less,
Assuming that the number of inorganic fine particles existing in the range of 80 nm to 135 nm in particle diameter is _D2 , it is important to satisfy the following formulas (6) to (8).
B ₂ /B ₁ ≦0.5 Formula (6)
0.85≦C ₂ /C ₁ formula (7)
0.55≦D ₂ /D ₁ ≦0.75 Formula (8)
In the water washing treatment, a dispersion of the toner added to deionized water containing a surfactant is shaken for 5 minutes under conditions of a shaking speed of 46.7 cm/sec and a shaking width of 4.0 cm. It is.

In the following, inorganic fine particles having a particle size in the range of 5 nm or more and 20 nm or less are also referred to as "small particle size inorganic fine particles".
Inorganic fine particles having a particle size in the range of 35 nm or more and 55 nm or less are also described as "medium particle size inorganic fine particles",
Inorganic fine particles having a particle size in the range of 80 nm or more and 135 nm or less are also referred to as "large particle size inorganic fine particles".

When the inorganic fine particles are present on the toner surface in the above-described state, the stress resistance is improved and both the cleaning property and the transfer property are improved at a high level, compared to the toner which does not satisfy the above conditions. The present inventors consider the mechanism by which this effect is obtained as follows.

In the present invention, it is important that the inorganic fine particles present on the toner surface exist in three different particle size ranges at a certain ratio. First, the cleaning process will be described. Inorganic fine particles having a particle diameter in the range of 5 nm to 20 nm must exist as a lubricating layer 2-4 upstream of the blade nip portion as shown in FIG. The small-diameter inorganic fine particles (5 nm or more and 20 nm or less) forming the lubricating layer 2-4 appropriately pass through the blade nip portion, so that the cleaning action by the blade is performed smoothly. If the amount of small-diameter inorganic fine particles passing through the blade nip portion is less than the desired amount, the contact surface between the cleaning blade 2-2 and the photoreceptor 2-1 has a high coefficient of friction, which causes chattering and curling of the blade. Cleaning failure occurs (toner passing through).

In order to stabilize the blade nip passage amount, the following formulas (2) and (6) must be satisfied.
0.20≦B ₁ /A ₁ ≦0.50 Formula (2)
B ₂ /B ₁ ≦0.5 Formula (6)
When B ₁ /A ₁ is less than 0.20, the number of particles passing through the blade nip portion is small, and the lubricating component is insufficient, so that stable cleaning performance cannot be obtained.
Also, when B ₂ /B ₁ exceeds 0.5, the amount of small-sized inorganic fine particles that can move freely away from the toner particle surface is reduced, resulting in chattering and curling of the cleaning blade.
Conversely, if B ₁ /A ₁ exceeds 0.50, the fluidity of the retention layer 2-6 due to the toner shown in FIG. 2 becomes too high, and cleaning fails. If the fluidity of the retention layer 2-6 is too high, the toner will move too quickly, hindering the formation of the blocking layer 2-5. In order to obtain stable blade cleaning properties, it is necessary to stably form the blocking layer 2-5 and the lubricating layer 2-4 upstream of the blade nip portion 2-3 as shown in FIG. . The blocking layer 2-5 is formed of inorganic fine particles having a large particle size, and serves to prevent toner from entering the blade nip portion 2-3. Small particle size inorganic fine particles enter the nearest portion of the blade nip portion 2-3 to form a lubricating layer 2-4. The blade cleaning is established. When the lubricating layer 2-4 is depleted, chattering and curling of the blade occur as described above, resulting in poor cleaning.

Next, the mechanism by which excellent cleaning performance and transfer performance can be obtained when the following formulas (3), (4), (7) and (8) are satisfied is considered as follows.
0.15≦C ₁ /A ₁ ≦0.55 Formula (3)
0.85≦C ₂ /C ₁ formula (7)
0.15≦D ₁ /A ₁ ≦0.55 Formula (4)
0.55≦D ₂ /D ₁ ≦0.75 Formula (8)

Appropriate fluidity is one of the properties required for the retention layer 2-6 shown in FIG. If the fluidity of the retention layer 2-6 is too high, the blocking layer 2-5 will be destroyed as described above, and cleaning will fail. Conversely, if the fluidity of the retention layer 2-6 is too low, the movement of the retention layer 2-6 will slow down and the toner will not be replaced. is insufficient, the blocking layer 2-5 and the lubricating layer 2-4 are not sequentially formed. Inorganic fine particles having a particle size of 35 nm or more and 55 nm or less are suitable for imparting appropriate fluidity to the retention layer 2-6. If the particle size is smaller than 35 nm, the fluidity of the retention layer 2-6 becomes too high, which is not preferable. If the particle diameter is larger than 55 nm, the inorganic fine particles adhering to the surface of the toner base particles are meshed with each other, and the movement of the staying layer becomes slow, resulting in insufficient fluidity.

Next, transferability will be described. In order to improve the transferability, it is necessary to reduce the non-electrostatic adhesion force of the toner, and for this purpose, it is effective to reduce the contact area by point-contacting the object with the inorganic fine particles. In order to effectively express this action, it is preferable to increase the particle size of the inorganic fine particles. The function as an external additive may not be exhibited.

In recent years, transfer systems often employ primary transfer in which an image is transferred from a photosensitive member to an intermediate transfer member, and secondary transfer in which an image is transferred from the intermediate transfer member to a recording medium. There are a wide variety of recording media, and recording materials with uneven surfaces such as embossed paper are sometimes used. A gap is formed between the surface of the material.

At this time, the transfer electric field is weakened by this gap, and there is a possibility that an image defect may occur in which the toner image is removed at the concave portion. In order to minimize the occurrence of such image defects, it is necessary to reduce the non-electrostatic adhesion force of the toner, and this can be achieved by adopting the configuration of the present invention.
In the present invention, inorganic fine particles with a particle size of 35 nm or more and 55 nm or less and inorganic fine particles with a particle size of 80 nm or more and 135 nm or less are used. When A ₁ , C ₁ and D ₁ satisfy the following relationship, the area ratio occupied by inorganic fine particles having a particle size of 35 nm or more can be increased and the non-electrostatic adhesion force can be reduced.
0.15≦C ₁ /A _1
0.15≤D1 / _A1
Further, the distance between the toner mother particles and the object can be maintained by the inorganic fine particles having a particle size of 35 nm or more, and the chance of contact between the surface of the mother particles and the object can be reduced as much as possible. In addition, it is possible to suppress burial of the inorganic fine particles when stress is applied to the toner.

When the toner moves from the photoreceptor to the intermediate transfer body by the primary transfer, some of the inorganic fine particles are separated from the surface of the toner base particles and remain on the surface of the photoreceptor. It will be in a state where the adhesion force has increased. In order _to prevent this phenomenon, it is necessary to increase _the adherence _of the inorganic fine particles to the toner base particles _. do.
0.85≦C ₂ /C ₁ formula (7)
0.55≦D ₂ /D ₁ ≦0.75 Formula (8)

Inorganic fine particles having a particle size of 35 nm or more and 55 nm or less should be improved in adhesion to toner base particles as much as possible. By doing so, detachment can be prevented and the particles can be left without being reduced even during the secondary transfer. Further, the inorganic fine particles having this particle size have appropriate fluidity even when they are fixed to the toner base particles, so that they are suitable for imparting appropriate movement to the toner retention layer described above.

On the other hand, inorganic fine particles having a particle size of 80 nm or more and 135 nm or less can contribute to a reduction in adhesive force during secondary transfer by increasing adhesion to toner base particles when _D1 and _D2 satisfy the following relationship. .
_0.55≤D2 / _D1

However, some of the inorganic fine particles with a particle size of 80 nm or more and 135 nm or less must be detached from the toner base particles so that _D1 and _D2 satisfy the following relationship.
_D2 / _D1≤0.75
The separated inorganic fine particles are necessary for forming the aforementioned blocking layer. The particle size of the inorganic fine particles suitable for forming the blocking layer is 80 nm or more and 135 nm or less. If the particle size is less than 80 nm, the blocking layer becomes poor and it becomes difficult to reliably block the toner. In addition, the probability of slipping through the blade is increased, which is not suitable for forming a stable blocking layer. In addition, if the particle diameter of the inorganic fine particles is larger than 135 nm, the inorganic fine particles are less likely to adhere to the toner base particles, and the abrasive force of the inorganic fine particles becomes too strong, possibly damaging the surface of the photoreceptor.

In the present invention, it is necessary that the number _A1 of the inorganic fine particles present in the particle size range of 5 nm or more and 200 nm or less satisfies the following formulas (1) and (5) in order to exhibit the above effects.
0.95≦A ₁ /(Number of all inorganic fine particles) Formula (1)
0.70≦(B ₁ /A ₁ +C ₁ /A ₁ +D ₁ /A ₁ ) Equation (5)

In the present invention, the coverage of the inorganic fine particles with respect to the toner particles must be 55% or more. If the coverage is less than 55%, the amount of the inorganic fine particles is insufficient, so that the above-described action required in the present invention cannot be satisfactorily exhibited.

Among the inorganic fine particles existing on the surface of the toner according to the present invention, the particle size distribution of the inorganic fine particles present in the range of 5 nm to 200 nm preferably has peaks in each of the following three ranges.
・Particle diameter range of 5 nm or more and 20 nm or less ・Particle diameter range of 35 nm or more and 55 nm or less ・Particle diameter range of 80 nm or more and 135 nm or less By having a peak in each range, the above action is more effectively exhibited. .

The present invention is particularly effective when using a photoreceptor with a low wear rate.
If the wear rate is high, scraping powder of the photoreceptor is generated and the lubricant can always be present in the blade nip portion, which facilitates stable cleaning.
On the other hand, when the wear rate is low, there is almost no scraping dust and the coefficient of friction increases due to deterioration of the photoreceptor surface (accumulation of discharge products), making blade cleaning difficult. It is easy to obtain the effect of the invention.

The inorganic fine particles used in the present invention include known inorganic fine particles such as titanium oxide fine particles, silica fine particles, alumina fine particles and strontium titanate fine particles. Silica fine particles are preferable as small-particle-size inorganic particles, medium-particle-size inorganic particles, and large-particle-size inorganic particles, and strontium titanate particles are preferable as medium-particle-size inorganic particles.
The reason why it is preferable to use strontium titanate fine particles as medium-sized inorganic fine particles is as follows.
Strontium titanate has a lower resistance than silica and can suppress electrostatic aggregation between toner particles, so it is more preferable for producing the appropriate fluidity required for the retention layer.

Silica fine particles include wet silica obtained by precipitation method, sol-gel method and the like, and dry silica obtained by deflagration method, fumed method and the like, but dry silica is more preferable because of ease of shape control.
Dry silica uses a silicon halogen compound or the like as a raw material.
Silicon tetrachloride is used as the silicon halogen compound, but silanes such as methyltrichlorosilane and trichlorosilane can be used alone, or a mixture of silicon tetrachloride and silanes can also be used as a raw material.

After the raw material is vaporized, it reacts with water produced as an intermediate in an oxyhydrogen flame, that is, a so-called flame hydrolysis reaction to obtain the desired silica.
For example, it utilizes the thermal decomposition oxidation reaction of silicon tetrachloride gas in oxygen and hydrogen, and the reaction formula is as follows.
SiCl ₄ +2H ₂ +O ₂ →SiO ₂ +4HCl

An example of producing the dry silica used in the present invention will be described below.
After oxygen gas was supplied to the burner and the ignition burner was ignited, hydrogen gas was supplied to the burner to form a flame. Next, a flame hydrolysis reaction was carried out, and the produced silica powder was collected.
The average particle size and shape can be arbitrarily adjusted by appropriately changing the silicon tetrachloride flow rate, oxygen gas supply flow rate, hydrogen gas supply flow rate, and residence time of silica in the flame.

It is preferable that the inorganic fine particles used in the present invention are subjected to a hydrophobic treatment. As the hydrophobizing agent, a silane compound, silicone oil, or a mixture thereof can be used. From the viewpoint of obtaining excellent dispersibility of the inorganic fine particles, the hydrophobizing treatment is performed only with the silane compound. is more preferred.

<Other inorganic fine particles>
The toner of the present invention may further contain inorganic fine particles, if necessary. The inorganic fine particles may be added internally to the toner particles, or may be mixed with the toner particles as an external additive. As the external additive, inorganic fine powders such as silica, titanium oxide, aluminum oxide and strontium titanate are preferred. The inorganic fine powder is preferably hydrophobized with a hydrophobizing agent such as a silane compound, silicone oil or a mixture thereof.

The amount of these other inorganic fine particles used is preferably 0.1 parts by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass of the toner particles. A known mixer such as a Henschel mixer can be used to mix the toner particles and other inorganic fine particles. Further, the timing of mixing the toner particles and the other inorganic fine particles may be either before or after the heat treatment described below.

<Amorphous resin>
The amorphous resin used in the toner of the present invention is not particularly limited, and the following polymers or resins can be used.
For example: Homopolymers of styrene and substituted products thereof such as polystyrene, poly-p-chlorostyrene and polyvinyltoluene; styrene-p-chlorostyrene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene copolymers, styrene - acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-methyl chloromethacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether Styrenic copolymers such as copolymers, styrene-vinyl methyl ketone copolymers, styrene-acrylonitrile-indene copolymers; polyvinyl chloride, phenolic resins, natural modified phenolic resins, natural resin modified maleic acid resins, acrylic resins , methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone-indene resin, petroleum-based resin, and the like.

Among these, it is preferable to use a polyester resin as a main component from the viewpoint that excellent low-temperature fixability can be obtained. Monomers used in the polyester unit of the polyester resin include polyhydric alcohols (divalent or trivalent or higher alcohols), polyvalent carboxylic acids (divalent or trivalent or higher carboxylic acids), acid anhydrides thereof, or lower Alkyl esters are used. Here, in order to prepare a branched polymer, it is effective to partially crosslink the molecules of the amorphous resin, and for this purpose, it is preferable to use a polyfunctional compound having a valence of 3 or more. Therefore, it is preferable that a carboxylic acid having a valence of 3 or higher, an acid anhydride thereof or a lower alkyl ester thereof, and/or an alcohol having a valence of 3 or higher are included as raw material monomers for the polyester unit.
As the polyhydric alcohol monomer used for the polyester unit of the polyester resin, the following polyhydric alcohol monomers can be used.

Examples of dihydric alcohol components 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, hydrogenated bisphenol A, bisphenol represented by the following formula (A) and derivatives thereof;

（式中、Ｒはエチレンまたはプロピレン基であり、ｘ及びｙはそれぞれ０以上の整数であり、かつ、ｘ＋ｙの平均値は０以上１０以下である。）
式（Ｂ）で示されるジオール類；

(Wherein, R is an ethylene or propylene group, x and y are each an integer of 0 or more, and the average value of x + y is 0 or more and 10 or less.)
diols represented by formula (B);

Examples of trihydric or higher alcohol components include the following. Sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol , 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene. Among these, glycerol, trimethylolpropane, and pentaerythritol are preferably used. These dihydric alcohols and trihydric or higher alcohols can be used alone or in combination.

As the polycarboxylic acid monomer used for the polyester unit of the polyester resin, the following polycarboxylic acid monomers can be used.
Examples of divalent carboxylic acid components include the following. Maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malonic acid, n-dodecenylsuccinic acid, isododecenylsuccinic acid , n-dodecylsuccinic acid, isododecylsuccinic acid, n-octenylsuccinic acid, n-octylsuccinic acid, isooctenylsuccinic acid, isooctylsuccinic acid, anhydrides of these acids and lower alkyl esters thereof. Among these, maleic acid, fumaric acid, terephthalic acid and n-dodecenylsuccinic acid are preferably used.

Examples of trivalent or higher carboxylic acids, acid anhydrides thereof and lower alkyl esters thereof include the following. 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra(methylenecarboxyl)methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid , Empol trimer acids, their acid anhydrides or their lower alkyl esters. Among these, 1,2,4-benzenetricarboxylic acid, ie, trimellitic acid or derivatives thereof, is particularly preferred because it is inexpensive and reaction control is easy. These bivalent carboxylic acids and trivalent or higher carboxylic acids can be used alone or in combination.

The method for producing the polyester unit of the present invention is not particularly limited, and known methods can be used. For example, the above alcohol monomer and carboxylic acid monomer are mixed at the same time, polymerized through an esterification reaction or a transesterification reaction, and a condensation reaction to produce a polyester resin. Moreover, the polymerization temperature is not particularly limited, but is preferably in the range of 180° C. or higher and 290° C. or lower. Polymerization catalysts such as titanium-based catalysts, tin-based catalysts, zinc acetate, antimony trioxide, and germanium dioxide can be used for the polymerization of the polyester units. In particular, polyester units polymerized using tin-based catalysts are preferred.

Further, the peak molecular weight of the amorphous resin used in the toner of the present invention is 4,000 or more and 13,000 or less from the viewpoint that excellent low-temperature fixability and hot offset resistance can be obtained. preferable.
Further, the acid value of the amorphous resin used in the toner of the present invention is 5 mgKOH/g or more and 20 mgKOH/g or less from the viewpoint that excellent charging stability can be obtained in a high-temperature and high-humidity environment. preferable.

Further, the hydroxyl value of the amorphous resin used in the toner of the present invention is preferably 20 mgKOH/g or more and 70 mgKOH/g or less from the viewpoint of obtaining excellent low-temperature fixability and storage stability.
Further, the amorphous resin used in the toner of the present invention may be a mixture of the amorphous resin A having a low molecular weight and the amorphous resin B having a high molecular weight. The content ratio (A/B) of the low-molecular-weight amorphous resin A and the high-molecular-weight amorphous resin B is 60/40 or more and 90/10 or less on a mass basis. It is preferable from the viewpoint that hot offset property can be obtained.

The low-molecular-weight amorphous resin A preferably has a peak molecular weight of 4,000 or more and 7,000 or less from the viewpoint of obtaining excellent low-temperature fixability.
In addition, it is preferable that the low-molecular-weight amorphous resin A has an acid value of 20 mgKOH/g or less from the viewpoint of obtaining excellent charging stability in a high-temperature, high-humidity environment.

The peak molecular weight of the high-molecular-weight amorphous resin B is preferably 10,000 or more and 20,000 or less from the viewpoint of obtaining excellent hot offset resistance.
Further, the acid value of the binder resin B having a high molecular weight is preferably 15 mgKOH/g or more and 30 mgKOH/g or less from the viewpoint of obtaining excellent charging stability in a high-temperature and high-humidity environment.

Moreover, as the amorphous resin, it is preferable to use a polyester resin having a succinic acid-derived unit containing an alkyl group having 8 to 24 carbon atoms, and it is more preferable to use dodecenylsuccinic acid. The ratio of the polyester resin having a succinic acid-derived unit containing an alkyl group having 8 to 24 carbon atoms to the polyester resin having no alkyl group having 8 or more carbon atoms is preferably 1% or more and 10% or less.

<Other amorphous resins>
As the amorphous resin used in the toner of the present invention, the following polymers are used in addition to the above amorphous resins for the purpose of improving pigment dispersibility, charging stability and blocking resistance of the toner. can be added in an amount that does not impair the effects of the present invention.
Other resins used for the amorphous resin of the toner of the present invention include, for example, the following resins. Homopolymers of styrene and substituted products thereof such as polystyrene, poly-p-chlorostyrene and polyvinyltoluene; styrene-p-chlorostyrene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene copolymers, styrene - acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-methyl chloromethacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether Styrenic copolymers such as copolymers, styrene-vinyl methyl ketone copolymers, styrene-acrylonitrile-indene copolymers; polyvinyl chloride, phenolic resins, natural modified phenolic resins, natural resin modified maleic acid resins, acrylic resins , methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone-indene resin, petroleum-based resin, and the like.

<Crystalline polyester>
A crystalline polyester resin as described below may be added to the toner of the present invention for the purpose of promoting the plasticizing effect of the toner and improving the low-temperature fixability.
The crystalline polyester is obtained by a polycondensation reaction of a monomer composition containing as main components an aliphatic diol having 2 to 22 carbon atoms and an aliphatic dicarboxylic acid having 2 to 22 carbon atoms. is an example.

The aliphatic diol having 2 to 22 carbon atoms (more preferably 6 to 12 carbon atoms) is not particularly limited, but a chain aliphatic diol is preferable, and a straight chain aliphatic diol is preferred. is more preferable. For example: Ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, dipropylene glycol, 1,4-butanediol, 1,4-butadiene glycol, trimethylene glycol, tetramethylene glycol, penta methylene glycol, 1,6-hexanediol, octamethylene glycol, nonamethylene glycol, decamethylene glycol, neopentyl glycol. Among these, linear aliphatics such as ethylene glycol, diethylene glycol, 1,4-butanediol and 1,6-hexanediol, and α,ω-diols are particularly preferred.

Of the alcohol components, preferably 50% by mass or more, more preferably 70% by mass or more, is alcohol selected from aliphatic diols having 2 to 22 carbon atoms.
In the present invention, polyhydric alcohol monomers other than the above aliphatic diols can also be used. Examples of the dihydric alcohol monomer among the polyhydric alcohol monomers include aromatic alcohols such as polyoxyethylenated bisphenol A and polyoxypropylenated bisphenol A; 1,4-cyclohexanedimethanol and the like. Moreover, the following are mentioned as a polyhydric-alcohol monomer more than trihydric among the said polyhydric-alcohol monomers. Aromatic alcohols such as 1,3,5-trihydroxymethylbenzene; pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methyl aliphatic alcohols such as propanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane and trimethylolpropane;

Furthermore, a monohydric alcohol may be used to the extent that the properties of the crystalline polyester are not impaired. Examples of the monohydric alcohol include the following. monofunctional alcohols such as n-butanol, isobutanol, sec-butanol, n-hexanol, n-octanol, lauryl alcohol, 2-ethylhexanol, decanol, cyclohexanol, benzyl alcohol and dodecyl alcohol;

On the other hand, the aliphatic dicarboxylic acid having 2 or more and 22 or less carbon atoms (more preferably 6 or more and 12 or less carbon atoms) is not particularly limited, but is preferably a chain aliphatic dicarboxylic acid. Group dicarboxylic acids are more preferred. Specific examples include the following. Oxalic Acid, Malonic Acid, Succinic Acid, Glutaric Acid, Adipic Acid, Pimelic Acid, Speric Acid, Glutaconic Acid, Azelaic Acid, Sebacic Acid, Nonanedicarboxylic Acid, Decanedicarboxylic Acid, Undecanedicarboxylic Acid, Dodecanedicarboxylic Acid, Maleic Acid, Fumaric Acid Acids, mesaconic acid, citraconic acid, itaconic acid, hydrolyzed acid anhydrides or lower alkyl esters thereof, and the like.
Among the carboxylic acid components, 50% by mass or more is preferably a carboxylic acid selected from aliphatic dicarboxylic acids having 2 to 22 carbon atoms, and 70% by mass or more is an aliphatic dicarboxylic acid having 2 to 22 carbon atoms. A carboxylic acid selected from is more preferred.

Polyvalent carboxylic acids other than the aliphatic dicarboxylic acids having 2 to 22 carbon atoms can also be used. Among other polyvalent carboxylic acid monomers, divalent carboxylic acids include the following. aromatic carboxylic acids such as isophthalic acid and terephthalic acid; aliphatic carboxylic acids such as n-dodecylsuccinic acid and n-dodecenylsuccinic acid; alicyclic carboxylic acids such as cyclohexanedicarboxylic acid; acid anhydrides or lower alkyl esters thereof;

Further, among other carboxylic acid monomers, examples of polyvalent carboxylic acids having a valence of 3 or more include the following. aromatic carboxylic acids such as 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, pyromellitic acid; -aliphatic carboxylic acids such as butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, their acid anhydrides or lower alkyl esters, etc. derivatives and the like.

Furthermore, it may contain a monovalent carboxylic acid to the extent that the properties of the crystalline polyester are not impaired. Examples of monovalent carboxylic acids include the following. Monocarboxylic acids such as naphthalenecarboxylic acid, salicylic acid, 4-methylbenzoic acid, 3-methylbenzoic acid, phenoxyacetic acid, biphenylcarboxylic acid, acetic acid, propionic acid, butyric acid, octanoic acid, decanoic acid, dodecanoic acid and stearic acid.

Crystalline polyesters can be produced according to conventional polyester synthesis methods. For example, the carboxylic acid monomer and the alcohol monomer described above are subjected to an esterification reaction or a transesterification reaction, followed by a polycondensation reaction under reduced pressure or by introducing nitrogen gas in a conventional manner to obtain the desired product. A crystalline polyester can be obtained.
The esterification or transesterification reaction can be carried out using a conventional esterification or transesterification catalyst such as sulfuric acid, titanium butoxide, dibutyltin oxide, manganese acetate and magnesium acetate, if necessary.

In addition, the above polycondensation reaction can be carried out using a known catalyst such as a usual polymerization catalyst such as titanium butoxide, dibutyltin oxide, tin acetate, zinc acetate, tin disulfide, antimony trioxide and germanium dioxide. . The polymerization temperature and catalyst amount are not particularly limited, and may be determined as appropriate.

In the esterification or transesterification reaction or the polycondensation reaction, all monomers may be mixed together in order to increase the strength of the resulting crystalline polyester. Moreover, in order to reduce the amount of low-molecular-weight components, a method of first reacting a divalent monomer and then adding and reacting a trivalent or higher monomer may be used.

<Wax>
The toner of the present invention may contain wax. Examples of waxes that can be used include the following. Hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, alkylene copolymers, microcrystalline wax, paraffin wax and Fischer-Tropsch wax; oxides of hydrocarbon waxes such as oxidized polyethylene wax or block copolymers thereof; Waxes mainly composed of fatty acid esters such as carnauba wax; deoxidized carnauba waxes and other fatty acid esters partially or wholly deoxidized. Furthermore, the following are mentioned. saturated straight-chain fatty acids such as palmitic acid, stearic acid and montanic acid; unsaturated fatty acids such as brassic acid, eleostearic acid and parinaric acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, ceryl alcohol, saturated alcohols such as silalcohol; polyhydric alcohols such as sorbitol; fatty acids such as palmitic acid, stearic acid, behenic acid and montanic acid; Esters with alcohols such as silalcohol; Fatty acid amides such as linoleic acid amide, oleic acid amide, and lauric acid amide; saturated fatty acid bisamides such as acid amide; unsaturated fatty acid amides such as ethylenebisoleic acid amide, hexamethylenebisoleic acid amide, N,N'dioleyladipate, N,N'dioleylsebacic acid amide; - Aromatic bisamides such as xylene bisstearic acid amide and N,N' distearyl isophthalic acid amide; waxes obtained by grafting vinyl monomers such as styrene and acrylic acid to aliphatic hydrocarbon waxes; partial esters of fatty acids and polyhydric alcohols such as behenic acid monoglyceride; vegetable oils and fats A methyl ester compound having a hydroxyl group obtained by hydrogenation of

Among these waxes, the following are preferable from the viewpoint of improving the interaction between the wax and the wax dispersant, and the low-temperature fixability and hot-offset resistance. Hydrocarbon waxes such as paraffin wax and Fischer-Tropsch wax, or fatty acid ester waxes such as carnauba wax. In the present invention, hydrocarbon waxes are more preferable from the viewpoint of further improving hot offset resistance.
In the present invention, the amount of wax used is preferably 1 part by mass or more and 20 parts by mass or less per 100 parts by mass of the binder resin.

Moreover, in the endothermic curve during temperature rise measured by a differential scanning calorimeter (DSC), the peak temperature of the maximum endothermic peak of the wax is preferably 45° C. or higher and 140° C. or lower. When the peak temperature of the maximum endothermic peak of the wax is within the above range, the toner can have both excellent storage stability and hot offset resistance, which is preferable.

<Wax dispersant>
A wax dispersant may be used in the present invention. Although not particularly limited, it is preferable to use a polymer obtained by graft-modifying a styrene-acrylic polymer to a polyolefin. More preferably, the styrene-acrylic polymer has units derived from cycloalkyl acrylate or units derived from cycloalkyl methacrylate.

The wax dispersant preferably has a weight average molecular weight (Mw) of 5,000 or more and 70,000 or less in the molecular weight distribution of the styrene-acrylic resin by GPC. When the weight average molecular weight (Mw) of the wax dispersant is within the above range, the dispersibility of the wax is improved, and at the same time, blocking resistance and hot offset resistance are improved.

When the weight-average molecular weight (Mw) is 5,000 or more, the wax dispersant remains in the toner, and the elution of the wax to the toner surface, which occurs when the toner is left at high temperature and high humidity for a long time, is suppressed. blocking resistance is improved. Further, when the weight-average molecular weight (Mw) is 70,000 or less, the wax finely dispersed in the toner can quickly migrate to the surface of the melted toner during fixation and melting, resulting in improved releasability during fixation and high-temperature offset. less likely to occur.

The polyolefin is not particularly limited, but is preferably selected from waxes used in the toner of the present invention, which will be described later, from the viewpoint of excellent affinity with the wax in the toner particles.
The polyolefin preferably has a maximum thermal peak temperature of 70° C. or higher and 90° C. or lower as measured using a differential scanning calorimeter (DSC).

As the polyolefin, the following hydrocarbon waxes are preferable. Low molecular weight polyethylene, low molecular weight polypropylene, alkylene copolymers, microcrystalline wax, paraffin wax, and Fischer-Tropsch wax.
Moreover, from the viewpoint of excellent reactivity during production of the wax dispersant, it is preferable to have a branched structural unit like polypropylene.

In the present invention, the method of graft-modifying the polyolefin with the styrene-acrylic polymer is not particularly limited, and conventionally known methods can be used.
In the polymer of the present invention, the styrene-acrylic polymer is not particularly limited as long as it has a cycloalkyl acrylate-derived unit or a cycloalkyl methacrylate-derived unit.

As the cycloalkyl acrylate-derived unit or the cycloalkyl methacrylate-derived unit, a saturated alicyclic hydrocarbon group is preferred. A saturated alicyclic hydrocarbon group having 3 to 18 carbon atoms is more preferable, and a saturated alicyclic hydrocarbon group having 4 to 12 carbon atoms is more preferable. Saturated alicyclic hydrocarbon groups include cycloalkyl groups, condensed polycyclic hydrocarbon groups, bridged ring hydrocarbon groups, spiro hydrocarbon groups and the like.

Examples of such saturated alicyclic groups include the following. cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, t-butylcyclohexyl group, cycloheptyl group, cyclooctyl group, tricyclodecanyl group, decahydro-2-naphthyl group, tricyclo[ ^{5.2.1.02 ,6} ]decane-8-yl group, pentacyclopentadecanyl group, isobornyl group, adamantyl group, dicyclopentanyl group, tricyclopentanyl group and the like.

The saturated alicyclic group can also have an alkyl group, a halogen atom, a carboxy group, a carbonyl group, a hydroxy group, etc. as a substituent. As the alkyl group, an alkyl group having 1 to 4 carbon atoms is preferred.
Among these saturated alicyclic groups, cycloalkyl groups, condensed polycyclic hydrocarbon groups, and bridged cyclic hydrocarbon groups are preferable, and cycloalkyl groups having 3 to 18 carbon atoms, substituted or unsubstituted dicyclopentanyl A substituted or unsubstituted tricyclopentanyl group is more preferred. A cycloalkyl group having 6 to 10 carbon atoms is more preferable, and a cyclohexyl group having 6 carbon atoms is particularly preferable.
The position and number of the substituents are arbitrary, and when there are two or more substituents, the substituents may be the same or different.

The styrene-acrylic polymer may be a homopolymer of a vinyl monomer (a) having a structural moiety derived from a saturated alicyclic compound, or may be a copolymer with another monomer (b).
Examples of the vinyl monomer (a) include the following. cyclopropyl acrylate, cyclobutyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, cycloheptyl acrylate, cyclooctyl acrylate, cyclopropyl methacrylate, cyclobutyl methacrylate, cyclopentyl methacrylate, cyclohexyl methacrylate, cycloheptyl methacrylate, cyclooctyl methacrylate, dihydrocyclopentadiethyl acrylate, Monomers such as dicyclopentanyl acrylate, dicyclopentanyl methacrylate, and combinations thereof.
Among these, cyclohexyl acrylate, cycloheptyl acrylate, cyclooctyl acrylate, cyclohexyl methacrylate, cycloheptyl methacrylate, and cyclooctyl methacrylate are preferred from the viewpoint of excellent hydrophobicity.

Examples of the other monomer (b) include the following. Styrenic monomers such as styrene, p-methylstyrene, m-methylstyrene, p-methoxystyrene, p-hydroxystyrene, p-acetoxystyrene, vinyltoluene, ethylstyrene, phenylstyrene, benzylstyrene; methyl acrylate, ethyl acrylate, Alkyl esters of unsaturated carboxylic acids such as butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, and 2-ethylhexyl methacrylate (the alkyl has 1 to 18 carbon atoms); vinyl esters such as vinyl acetate Monomers; vinyl ether monomers such as vinyl methyl ether; halogen-containing vinyl monomers such as vinyl chloride; diene monomers such as butadiene and isobutylene, and combinations thereof.
For polarity adjustment, a monomer that adds an acid group or a hydroxyl group may be added. Monomers that add an acid group or a hydroxyl group include acrylic acid, methacrylic acid, maleic anhydride, maleic acid half ester, and 2-ethylhexyl acrylate.

In the present invention, the styrene-acrylic resin preferably has a monomer unit represented by the following formula (2) from the viewpoint that a toner having excellent low-temperature fixability can be obtained.
When the styrene-acrylic resin has a monomer unit represented by the following formula (2), the glass transition temperature (Tg) of the polymer tends to decrease. As a result, when the wax dispersant is contained in the toner particles, even if the toner is allowed to stand at high temperature and high humidity for a long time, the chargeability does not deteriorate and the low-temperature fixability is further improved.

[In formula (2), R ³ represents a hydrogen atom or a methyl group, and n represents an integer of 1 or more and 18 or less. (n is preferably an integer of 2 or more and 7 or less. When within this range, the glass transition temperature (Tg) can be efficiently lowered. When n is less than 2, the glass transition temperature (Tg) is lowered. If it is more than 7, the glass transition temperature (Tg) will be too low for the mesh, making adjustment difficult.)]

When a toner is produced using the polymer, the binder resin for the toner is not particularly limited, but when a polyester resin is used as the binder resin, the wax dispersant is sufficiently effective.
The compatibility between the polyester resin and the hydrocarbon wax is low. Therefore, when a polyester resin is used as the binder resin in the present invention, if the wax is added as it is to form a toner, the wax segregates in the toner and free wax or the like is generated. In some cases, problems such as poor charging may occur.
Further, the polymer is preferably contained in an amount of 1.0 parts by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass of the binder resin.

<Wax Masterbatch>
The wax may be melt-mixed with the resin, wax, and wax dispersant and used as a masterbatch without being mixed during toner production.

<Colorant>
Colorants that can be contained in the toner include the following.
Examples of black colorants include carbon black; black toned by using a yellow colorant, a magenta colorant, and a cyan colorant. A pigment may be used alone as a coloring agent, but it is more preferable to use a dye and a pigment in combination to improve the definition from the viewpoint of image quality of a full-color image.

Examples of magenta toner pigments include the following. C. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48:2, 48:3, 48:4, 49, 50, 51, 52, 53, 54, 55, 57:1, 58, 60, 63, 64, 68, 81: 1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 146, 147, 150, 163, 184, 202, 206, 207, 209, 238, 269, 282; I. Pigment Violet 19; C.I. I. Bat Red 1, 2, 10, 13, 15, 23, 29, 35.

Dyes for magenta toner include the following. C. I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121; C.I. I. disperse thread 9;C. I. Solvent Violet 8, 13, 14, 21, 27; C.I. I. Oil-soluble dyes such as Disper Violet 1, C.I. I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40; C.I. I. Basic dyes such as Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28.

Examples of cyan toner pigments include the following. C. I. Pigment Blue 2, 3, 15:2, 15:3, 15:4, 16, 17; C.I. I. Bat Blue 6; C.I. I. Acid Blue 45, a copper phthalocyanine pigment having a phthalocyanine skeleton substituted with 1 to 5 phthalimidomethyl groups.
As dyes for cyan toners, C.I. I. There is Solvent Blue 70.

Examples of yellow toner pigments include the following. C. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 62, 65, 73, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155, 168, 174, 175, 176, 180, 181, 185; I. Bat Yellow 1, 3, 20.
As a yellow toner dye, C.I. I. There is Solvent Yellow 162.
The amount of the colorant used is preferably 0.1 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the binder resin.

<Developer>
The toner of the present invention can be used as a one-component developer, but it is recommended to mix it with a magnetic carrier and use it as a two-component developer to further improve dot reproducibility and provide stable images over a long period of time. It is preferable in that it can be obtained.
As the magnetic carrier, for example, the following known carriers can be used. Iron powder whose surface is oxidized or unoxidized, metal particles such as iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, chromium, rare earths, alloy particles thereof, and oxide particles. A magnetic substance-dispersed resin carrier (so-called resin carrier) containing a magnetic substance such as ferrite, a magnetic substance, and a binder resin that holds the magnetic substance in a dispersed state.
When the toner of the present invention is mixed with a magnetic carrier and used as a two-component developer, the carrier mixing ratio at that time is 2% by mass or more and 15% by mass or less as the toner concentration in the two-component developer. is preferable, and it is more preferable to make it 4% by mass or more and 13% by mass or less.

<Toner manufacturing method>
A method for producing a toner according to the present invention, which has toner particles containing a binder resin and a colorant, and inorganic fine particles coating the toner particles, comprises a toner base particle preparation step, a first external addition step, It has a heat treatment step and a second external addition step in this order.
In the toner base particle preparation step, toner base particles containing a binder resin and a colorant are prepared.

In the first external addition step, inorganic fine particles having a primary particle size of 35 nm or more and 55 nm or less (medium particle size inorganic fine particles) and primary particles having a size of 80 nm or more and 135 nm or less Inorganic fine particles (large particle diameter inorganic fine particles) are externally added.
The external additive amount is 1.0 to 5.0 parts by mass of the medium-sized inorganic fine particles and 1.5 to 6.0 parts by mass of the large-sized inorganic fine particles with respect to 100 parts by mass of the toner base particles. part.

In the heat treatment step, the toner particles externally added with medium-sized inorganic fine particles and large-sized inorganic fine particles in the first external addition step are treated with hot air.
In the second external addition step, inorganic fine particles having a primary particle size of 5 nm or more and 20 nm or less (inorganic fine particles having a small particle size) and primary particles having a particle size of 80 nm or more and 135 nm or less. Inorganic fine particles (large particle diameter inorganic fine particles) are externally added.
The amount of the external additive is 0.3 to 2.0 parts by mass of the small-sized inorganic fine particles and 0.5 to 4.0 parts by mass of the large-sized inorganic fine particles per 100 parts by mass of the heat-treated toner particles. 0 part by mass.

<Method for producing toner particles>
The toner particles may be produced by any conventionally known method such as a melt-kneading method, an emulsion phase inversion method, a suspension polymerization method, an emulsion aggregation method, and the like. From the viewpoint of finely dispersing the colorant particles in the amorphous resin, a melt-kneading method of melt-kneading the binder resin, the resin composition, and the crystalline polyester, cooling the kneaded product, and then pulverizing and classifying the kneaded product is preferable. .
A toner manufacturing procedure by the melt-kneading method will be described below.

In the raw material mixing step, predetermined amounts of other components such as a binder resin, a wax, a colorant, and, if necessary, a charge control agent are weighed and mixed as materials constituting the toner particles. Examples of the mixing device include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, a Nauta mixer, and a Mechanohybrid (manufactured by Nippon Coke Kogyo Co., Ltd.).

Next, the mixed materials are melt-kneaded to disperse wax and the like in the binder resin. In the melt-kneading process, a batch-type kneader such as a pressure kneader or a Banbury mixer, or a continuous kneader can be used, and single-screw or twin-screw extruders are the mainstream because of their superiority in continuous production. ing. For example, KTK type twin-screw extruder (manufactured by Kobe Steel, Ltd.), TEM type twin-screw extruder (manufactured by Toshiba Machine Co., Ltd.), PCM kneader (manufactured by Ikegai Co., Ltd.), twin-screw extruder (Kei・Kneader (manufactured by Busu Co., Ltd.), Kneadex (manufactured by Nippon Coke Industry Co., Ltd.), and the like. Furthermore, the resin composition obtained by melt-kneading may be rolled with two rolls or the like and cooled with water or the like in the cooling step.

The cooled resin composition is then pulverized to a desired particle size in a pulverization step. In the pulverization step, after coarsely pulverizing with a pulverizer, finely pulverize with a fine pulverizer. Examples of pulverizers include crushers, hammer mills, feather mills, and the like. Examples of fine pulverizers include Kryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), Super Rotor (manufactured by Nisshin Engineering Co., Ltd.), Turbo Mill (manufactured by Freund Turbo Co., Ltd.), and fine pulverization by an air jet method. machines, etc.

Thereafter, the particles are classified using a classifier or a sieving machine as necessary to obtain classified products (toner particles). Examples of classifiers and sieving machines include the following. Inertial classifier Elbow Jet (manufactured by Nittetsu Mining Co., Ltd.), Centrifugal classifier Turboplex (manufactured by Hosokawa Micron Corporation), TSP Separator (manufactured by Hosokawa Micron Corporation), Faculty (manufactured by Hosokawa Micron Corporation), etc. .

In the method for producing the toner of the present invention, it is important to add inorganic fine particles to the obtained toner powder particles (hereinafter also referred to as toner base particles) before the heat treatment step. As a method for adding the inorganic fine particles to the toner base particles, a predetermined amount of the toner base particles and the inorganic fine particles are blended, and the mixture is stirred and mixed using a high-speed stirrer as an external adder that applies a shearing force to the powder. Examples of high-speed stirrers include Henschel Mixer, Mechanohybrid (manufactured by Nippon Coke Co., Ltd.), Super Mixer, and Nobilta (manufactured by Hosokawa Micron Corporation).
Subsequently, inorganic fine particles are thermally fixed to the surfaces of the obtained toner base particles using a heat treatment apparatus as shown in FIG. 1 in a heat treatment step.

Hereinafter, a specific example of a method for heat-treating resin particles using the heat-treating apparatus shown in FIG. 1 will be described.
The resin particles quantitatively supplied by the raw material constant supply means 1 are guided to the introduction pipe 3 installed on the vertical line of the raw material supply means by the compressed gas adjusted by the compressed gas flow rate adjusting means 2 . The mixture that has passed through the introduction pipe 3 is uniformly dispersed by a conical protruding member 4 provided in the central part of the raw material supply means, and is guided to the supply pipes 5 extending radially in eight directions to be heat-treated in the processing chamber. lead to 6.

At this time, the flow of the resin particles supplied to the processing chamber 6 is regulated by the regulating means 9 provided in the processing chamber 6 for regulating the flow of the resin particles. Therefore, the resin particles supplied to the processing chamber 6 are heat-treated while swirling in the processing chamber 6 and then cooled.
Hot air for heat-treating the supplied resin particles is supplied from the hot air supply means 7, distributed by the distribution member 12, and spirally swirled in the processing chamber 6 by the swirling member 13 for swirling the hot air. Let it be introduced. As for the configuration, the swirling member 13 for swirling the hot air has a plurality of blades, and the swirling of the hot air can be controlled by the number and angle of the blades. The hot air supplied into the processing chamber 6 preferably has a temperature of 100° C. or higher and 300° C. or lower, more preferably 130° C. or higher and 170° C. or lower at the outlet of the hot air supply means 7 . If the temperature at the outlet of the hot air supply means 7 is within the above range, it is possible to treat the particles uniformly while preventing fusion and coalescence of the resin particles due to overheating of the resin particles.

Hot air is supplied from the hot air supply means 7 . Furthermore, the heat-treated resin particles that have been heat-treated are cooled by cool air supplied from the cool-air supply means 8 . The temperature of the cold air supplied from the cold air supply means 8 is preferably -20°C or higher and 30°C or lower. If the temperature of the cold air is within the above range, the heat-treated resin particles can be efficiently cooled, and fusion and coalescence of the heat-treated resin particles can be prevented without inhibiting uniform heat treatment of the resin particles. can be done. Also, the absolute water content of the cool air is preferably 0.5 g/m ³ or more and 15.0 g/m ³ or less.

The cooled heat-treated resin particles are then recovered by a recovery means 10 at the lower end of the processing chamber 6 . A blower (not shown) is provided at the end of the recovery means 10, and the particles are suction-conveyed by the blower.
The powder particle supply port 14 is provided so that the swirling direction of the supplied resin particles and the swirling direction of the hot air are the same, and the recovery means 10 also maintains the swirling direction of the swirled resin particles. It is provided in the tangential direction on the outer peripheral portion of the processing chamber 6 so as to do so. Furthermore, the cold air supplied from the cold air supply means 8 is configured to be supplied horizontally and tangentially from the outer peripheral portion of the apparatus to the inner peripheral surface of the processing chamber. The swirling direction of the resin particles before heat treatment supplied from the powder particle supply port 14, the swirling direction of the cold air supplied from the cold air supply means 8, and the swirling direction of the hot air supplied from the hot air supply means 7 are all the same direction. Therefore, no turbulent flow occurs in the processing chamber, the swirl flow in the device is strengthened, a strong centrifugal force is applied to the resin particles before heat treatment, and the dispersibility of the resin particles before heat treatment is further improved, so that the number of coalesced particles is small. , heat-treated resin particles having a uniform shape can be obtained.

If coarse particles are present after the heat treatment, the method for producing the toner of the present invention may optionally include a step of removing coarse particles by classification. Classifiers for removing coarse particles include Turboplex, TSP, TTSP, Cliffis (manufactured by Hosokawa Micron Corporation), and Elbow Jet (manufactured by Nittetsu Mining Co., Ltd.).

Furthermore, after the heat treatment, if necessary, a sieving machine may be used to screen out coarse particles and the like. As a sieving machine, Ultrasonic (manufactured by Koei Sangyo Co., Ltd.); Resona Sieve, Gyro Shifter (Tokuju Kosakusho Co., Ltd.); Turbo Screener (manufactured by Freund Turbo Co., Ltd.); made) and the like.
The heat treatment step of the present invention may be performed after the fine pulverization or after classification.
The toner of the present invention preferably has an average circularity of 0.955 or more, more preferably 0.960 or more. When the average circularity of the toner is within the above range, the transfer efficiency of the toner is improved.
Methods for measuring various physical properties of toner and raw materials are described below.

<Method for measuring number average particle size (D1) of primary particles of inorganic fine particles>
The number average particle diameter of the primary particles of the external additive is measured using a transmission electron microscope (TEM) "JEM2800" (manufactured by JEOL Ltd.).
First, a measurement sample is prepared. 1 mL of isopropanol is added to about 5 mg of the external additive, and dispersed for 5 minutes with an ultrasonic disperser (ultrasonic cleaner). Next, one drop of the above-mentioned dispersion liquid was placed on a microgrid (150 mesh) with a supporting film for TEM, and dried to prepare a measurement sample.

Next, with a transmission electron microscope (TEM), under the condition of an accelerating voltage of 200 kV, an image is acquired at a magnification (for example, 200 k to 1 M times) at which the external additive in the field of view can be sufficiently measured. The particle size of 100 primary particles of the external additive is measured to determine the number average particle size. The particle size of the primary particles may be measured manually or using a measuring tool.

<Method for measuring weight average molecular weight of resin>
The molecular weight distribution of the THF-soluble portion of the resin was measured by gel permeation chromatography (GPC) as follows.
First, the toner was dissolved in tetrahydrofuran (THF) at room temperature for 24 hours. The solution obtained thereafter was filtered using a solvent-resistant membrane filter "Maeshori Disk" (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution was adjusted so that the concentration of THF-soluble components was about 0.8% by mass. Using this sample solution, measurements were made under the following conditions.

Apparatus: HLC8120 GPC (detector: RI) (manufactured by Tosoh Corporation)
Column: 7 columns of Shodex KF-801, 802, 803, 804, 805, 806, 807 (manufactured by Showa Denko K.K.)
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 mL/min Oven temperature: 40.0°C
Sample injection volume: 0.10 mL

A molecular weight calibration curve prepared using a standard polystyrene resin was used to calculate the molecular weight of the sample.
Examples of standard polystyrene resins include the following. Product name "TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500” manufactured by Tosoh Corporation.

<Method for Measuring Weight Average Particle Diameter (D4) of Toner Particles>
The weight average particle diameter (D4) of toner particles is calculated as follows. As a measurement device, a precision particle size distribution measurement device "Coulter Counter Multisizer 3" (registered trademark, manufactured by Beckman Coulter, Inc.) using a pore electrical resistance method equipped with a 100 μm aperture tube is used. The attached dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter, Inc.) is used for setting the measurement conditions and analyzing the measurement data. Measurement was performed with 25,000 effective measurement channels, and the measurement data was analyzed and calculated.

The electrolytic aqueous solution used for the measurement can be prepared by dissolving special-grade sodium chloride in ion-exchanged water so that the concentration is about 1% by mass, such as "ISOTON II" (manufactured by Beckman Coulter, Inc.). .
Before conducting the measurement and analysis, the dedicated software was set as follows.
In the "change standard measurement method (SOM) screen" of the dedicated software, set the total number of counts in control mode to 50,000 particles, set the number of measurements to 1, and set the Kd value to "standard particle 10.0 μm" (Beckman・Values obtained using Coulter Co., Ltd.) were set. The threshold and noise level were automatically set by pressing the threshold/noise level measurement button. Also, the current was set to 1600 μA, the gain was set to 2, the electrolyte was set to ISOTON II, and flashing of the aperture tube after measurement was checked.
In the "pulse-to-particle size conversion setting screen" of the dedicated software, the bin interval was set to logarithmic particle size, the particle size bin was set to 256 particle size bins, and the particle size range was set to 2 μm or more and 60 μm or less.
A specific measuring method is as follows.

(1) About 200 mL of the electrolytic aqueous solution was placed in a 250 mL round-bottomed glass beaker exclusively for Multisizer 3, set on a sample stand, and stirred with a stirrer rod counterclockwise at 24 rpm. Dirt and air bubbles inside the aperture tube were removed in advance by the "flush aperture" function of the analysis software.
(2) About 30 mL of the electrolytic aqueous solution was placed in a 100-mL flat-bottomed glass beaker, and about 0.3 mL of a diluted solution obtained by diluting the following "Contaminon N" with ion-exchanged water to 3 times its weight as a dispersant was added. .
・Contaminon N: A 10% by weight aqueous solution of a neutral detergent for washing precision measuring instruments at pH 7 consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd.

(3) A water tank of an ultrasonic disperser "Ultrasonic Dispersion System Tetora 150" (manufactured by Nikkaki Bios Co., Ltd.) with an electrical output of 120 W and two oscillators with an oscillation frequency of 50 kHz built in with a phase shift of 180 degrees. A predetermined amount of ion-exchanged water was placed in the water tank, and about 2 mL of the contaminon N was added to the water tank.
(4) The beaker of (2) was set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser was operated. Then, the height position of the beaker was adjusted so that the resonance state of the liquid level of the electrolytic aqueous solution in the beaker was maximized.

(5) While the electrolytic aqueous solution in the beaker in (4) was irradiated with ultrasonic waves, about 10 mg of toner was added little by little to the electrolytic aqueous solution and dispersed. Then, the ultrasonic dispersion treatment was continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water in the water tank was appropriately adjusted to 10°C or higher and 40°C or lower.
(6) The electrolytic aqueous solution of (5) above, in which the toner was dispersed, was added dropwise to the round-bottomed beaker of (1) above set in the sample stand, and the measured concentration was adjusted to about 5%. . The measurement was continued until the number of measured particles reached 50,000.
(7) The measurement data was analyzed with the dedicated software attached to the apparatus, and the weight average particle size (D4) was calculated. The "average diameter" on the analysis/volume statistical value (arithmetic mean) screen when graph/volume % was set using dedicated software was taken as the weight average particle diameter (D4).

<Method for Measuring Average Circularity of Toner Particles>
The average circularity of the toner particles was measured using a flow type particle image analyzer "FPIA-3000" (manufactured by Sysmex Corporation) under measurement and analysis conditions during calibration work.
The measurement principle of the flow-type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation) is to take a still image of flowing particles and perform image analysis. A sample added to the sample chamber is delivered to the flat sheath flow cell by a sample aspiration syringe. The sample fed into the flat sheath flow is sandwiched between the sheath fluids to form a flat flow. The sample passing through the flat sheath flow cell is irradiated with strobe light at intervals of 1/60 second, and it is possible to photograph the flowing particles as a still image. In addition, since the flow is flat, it is imaged in a focused state. The particle image is captured by a CCD camera, and the captured image has a field of view of 512 pixels × 512 pixels, and is image-processed at an image processing resolution of 0.37 × 0.37 μm per pixel to obtain the contour of each particle image. Extraction is performed, and the projected area, perimeter, etc. of the particle image are measured.

Next, the projected area S and the peripheral length L of each particle image are obtained. Using the projected area S and the perimeter L, the equivalent circle diameter and circularity are obtained. The equivalent circle diameter is the diameter of a circle having the same area as the projected area of the particle image, and the degree of circularity C is obtained by dividing the perimeter of the circle obtained from the equivalent circle diameter by the perimeter L of the projected particle image. It is defined as a value and calculated by the following formula.
Circularity C=2×(π×S) ^1/2 /L

When the particle image is perfectly circular, the degree of circularity is 1.000.
After calculating the circularity of each particle, the range of circularity from 0.2 to 1.0 is divided into 800 channels, and the average value is calculated using the central value of each channel as the representative value to calculate the average circularity.

A specific measuring method is as follows. First, 0.02 g of a surfactant, preferably sodium dodecylbenzenesulfonate, was added as a dispersant to 20 mL of ion-exchanged water. After that, 0.02 g of the sample to be measured is added, and dispersed for 2 minutes using a tabletop ultrasonic cleaner/disperser with an oscillation frequency of 50 kHz and an electrical output of 150 W (for example, "VS-150" manufactured by Vervoclear Co., Ltd.). It was treated and used as a dispersion for measurement. At that time, the temperature of the dispersion liquid is appropriately cooled to 10° C. or higher and 40° C. or lower.

For the measurement, the flow type particle image analyzer equipped with a standard objective lens (10x magnification) was used, and the particle sheath "PSE-900A" (manufactured by Sysmex Corporation) was used as the sheath liquid. The dispersion liquid prepared according to the above procedure was introduced into the flow type particle image analyzer, and 3,000 toner particles were counted in the HPF measurement mode and the total count mode. Then, the binarization threshold during particle analysis was set to 85%, and the analysis particle diameter was limited to a circle equivalent diameter of 2.00 μm or more and 200.00 μm or less, and the average circularity of the toner was obtained.

In the measurement, automatic focus adjustment is performed using standard latex particles (for example, 5200A manufactured by Duke Scientific diluted with deionized water) before starting the measurement. After that, it is preferable to perform focus adjustment every two hours from the start of measurement.
In the following examples, a flow-type particle image analyzer with a calibration certificate issued by Sysmex Corporation was used. Measurement was performed under the measurement and analysis conditions when the calibration certification was received, except that the analyzed particle diameter was limited to a circle equivalent diameter of 2.00 μm or more and 200.00 μm or less.

<Measurement of glass transition temperature (Tg) of resin>
The glass transition temperature of the resin is measured according to ASTM D3418-82 using a differential scanning calorimeter "Q2000" (manufactured by TA Instruments).
The melting points of indium and zinc are used to correct the temperature of the device detector, and the heat of fusion of indium is used to correct the amount of heat.
Specifically, about 5 mg of resin was precisely weighed and placed in an aluminum pan, and an empty aluminum pan was used as a reference. Measure in minutes. The temperature is once raised to 180° C., held for 10 minutes, then lowered to 30° C., and then raised again. During this second heating process, a change in specific heat is obtained in the temperature range of 30 to 100°C. A straight line equidistant in the vertical axis direction from the baseline before the specific heat change occurs and the baseline after the specific heat change occurs is defined as the midpoint line. The temperature at the intersection of the midpoint line and the differential thermal curve (so-called midpoint glass transition temperature) is defined as the glass transition temperature (Tg) of the resin.

<Measurement of particle size of primary particles of inorganic fine particles on toner surface>
The particle size of the primary particles of the inorganic fine particles on the toner surface is determined by observing the inorganic fine particles externally added to the toner base particles using a scanning electron microscope (SEM) "S-4700" (manufactured by Hitachi, Ltd.). I asked.
The observation magnification was appropriately adjusted according to the size of the inorganic fine particles, but in the field of view magnified up to 200,000 times, the major diameters of the primary particles were measured, and the average value was taken as the number average particle diameter. The field of view is measured at 10 points in a 2 μm×2 μm square area.

<Method for measuring coverage by ESCA>
When silica fine particles are used as the inorganic fine particles, the coverage of the inorganic fine particles is the amount of silicon atoms derived from silica present on the surface of the toner particles (hereinafter also referred to as the amount of Si) measured by ESCA (X-ray photoelectron spectroscopy). ). ESCA is an analysis method for detecting atoms in a region of several nanometers or less in the depth direction of the sample surface. Therefore, it is possible to detect the atoms on the surface of the toner. As a sample holder, a platen with a diameter of 60 mm attached to the apparatus (provided with a screw hole with a diameter of about 1 mm for fixing the sample) was used. Since the screw hole of the platen penetrates, the hole is closed with resin or the like to prepare a concave portion for powder measurement with a depth of about 0.5 mm. A sample was prepared by stuffing the measurement sample into the recess with a spatula or the like and scraping it off.
The ESCA apparatus and measurement conditions are as follows.

Apparatus used: PHI5000VersaProbe II manufactured by ULVAC-Phi, Inc.
Analysis method: Narrow analysis Measurement conditions:
X-ray source: Al-Kα
X-ray conditions: 100 μm 25 W 15 kV
Photoelectron uptake angle: 45°
Pass Energy: 58.70 eV
Measurement range: 300 μm×200 μm
Measurement was performed under the above conditions.

In the analysis method, first, the peak derived from the CC bond of the carbon 1s orbital is corrected to 285 eV. After that, from the peak area derived from the silicon 2p orbital whose peak top is detected at 100 eV or more and 105 eV or less, by using the relative sensitivity factor provided by ULVAC-Phi, Inc., the amount of Si derived from silica with respect to the total amount of constituent elements Calculate Next, the silica alone applied to the toner was measured in the same manner as described above, the amount of Si derived from silica was calculated with respect to the total amount of constituent elements, and the toner was measured with respect to the Si amount when the external additive alone was measured. The ratio of the amount of Si at the time is defined as the silica coverage in the present invention.

<Method for measuring adhesion rate of silica fine particles>
In the present invention, the fixed silica fine particles are defined as follows.
20 g of ion-exchanged water and 0.4 g of the surfactant Contaminon N below are placed in a 30 cc glass vial (for example, manufactured by Nichiden Rika Glass Co., Ltd., VCV-30, outer diameter: 35 mm, height: 70 mm). Mix well to make a dispersion.
・Contaminon N (10% by mass aqueous solution of a neutral detergent for cleaning precision measuring instruments with a pH of 7 consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd.)

1.0 g of toner is added to this glass vial and allowed to stand until the toner spontaneously settles to prepare a pretreatment dispersion. It is assumed that silica fine particles that do not peel off even when this dispersion is shaken for 5 minutes at a shaking speed of 46.7 cm/sec and a shaking width of 4.0 cm are fixed. A centrifugal separator is used to separate the toner in which the silica fine particles remain and the silica fine particles that have been detached. The centrifugation step was performed at 3700 rpm for 30 minutes. The toner in which the silica fine particles remained was collected by suction filtration and dried to obtain the separated toner.

The sticking rate is measured as follows.
First, the amount of silica fine particles contained in the toner before the separation step is quantified. A wavelength dispersive X-ray fluorescence spectrometer Axios advanced (manufactured by PANalytical) is used to measure the Si element intensity: Si—B in the toner particles.
Next, the Si element intensity: Si-A of the toner after the separation step is similarly measured. The fixation rate is calculated using the following formula.
Adhesion rate (%) = (Si-A/Si-B) x 100

The basic configuration and features of the present invention have been described above. Hereinafter, the present invention will be specifically described based on examples. However, the technical scope of the present invention is by no means limited to this.

<Production Example of Amorphous Resin A>
· Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 72.0 parts by mass (0.20 mol; 100.0 mol% relative to the total number of polyhydric alcohol moles)
- Terephthalic acid: 28.0 parts by mass (0.17 mol; 100.0 mol% relative to the total number of moles of polyvalent carboxylic acid)
Tin (II) 2-ethylhexanoate (esterification catalyst): 0.5 parts by mass The above materials were weighed into a reactor equipped with a cooling tube, a stirrer, a nitrogen inlet tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 4 hours while stirring at a temperature of 200°C.
Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa and maintained for 1 hour, then cooled to 180° C. and returned to atmospheric pressure (first reaction step).

- Trimellitic anhydride: 1.3 parts by mass (0.01 mol; 4.0 mol% relative to the total number of moles of polyvalent carboxylic acid)
· tert-butyl catechol (polymerization inhibitor): 0.1 parts by mass After that, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the temperature is maintained at 180 ° C., reacted for 1 hour, ASTM After confirming that the softening point measured according to D36-86 reached 120° C., the temperature was lowered to stop the reaction (second reaction step). The glass transition temperature Tg of the obtained amorphous resin A was 57°C.

<Production example of crystalline resin B>
・Hexanediol: 33.9 parts by mass (0.29 mol; 100.0 mol% with respect to the total number of moles of polyhydric alcohol)
· Dodecanedioic acid: 66.1 parts by mass (0.29 mol; 100.0 mol% relative to the total number of polyvalent carboxylic acid moles)
Tin (II) 2-ethylhexanoate: 0.5 parts by mass The above materials were weighed into a reactor equipped with a cooling tube, a stirrer, a nitrogen inlet tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 3 hours while stirring at a temperature of 140°C.
After that, the pressure in the reaction tank was lowered to 8.3 kPa, the temperature was maintained at 200° C., and reaction was carried out for 4 hours to obtain a crystalline resin B (first reaction step). The obtained crystalline resin B had a weight average molecular weight Mw of 10,000 and a melting peak temperature Tp of 71°C.

<Production Example of Amorphous Resin C>
· Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 70.0 parts by mass (0.20 mol; 100.0 mol% relative to the total number of polyhydric alcohol moles)
- Terephthalic acid: 27.0 parts by mass (0.17 mol; 100.0 mol% with respect to the total number of polyvalent carboxylic acid moles)
- Dodecenyl succinic anhydride: 3 parts by mass - Tin (II) 2-ethylhexanoate (esterification catalyst): 0.5 parts by mass Materials were weighed. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 4 hours while stirring at a temperature of 200°C.
Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa and maintained for 1 hour, then cooled to 180° C. and returned to atmospheric pressure (first reaction step).

- Trimellitic anhydride: 1.3 parts by mass (0.01 mol; 4.0 mol% relative to the total number of moles of polyvalent carboxylic acid)
· tert-butyl catechol (polymerization inhibitor): 0.1 part by mass After that, the above materials were added, the pressure in the reaction tank was lowered to 8.3 kPa, and the temperature was maintained at 180°C, and the reaction was allowed to proceed for 1 hour. After confirming that the softening point measured according to ASTM D36-86 reached 120° C., the temperature was lowered to stop the reaction (second reaction step). The glass transition temperature Tg of the obtained amorphous resin C was 57°C.

<Production example of polymer 1>
300 parts by mass of xylene and 10 parts by mass of hydrocarbon wax (softening point: 90° C.) were placed in an autoclave reactor equipped with a thermometer and a stirrer, thoroughly dissolved, and replaced with nitrogen. After that, a mixed solution of the following materials was added dropwise at 180° C. for 3 hours for polymerization, and the mixture was maintained at this temperature for 30 minutes.
・Styrene 68.0 parts by mass ・Methacrylic acid 5.0 parts by mass ・Cyclohexyl methacrylate 5.0 parts by mass ・Butyl acrylate 12.0 parts by mass ・Xylene 250 parts by mass .

<Production example of wax masterbatch>
・Amorphous resin C: 40 parts by mass ・Polymer 1: 30 parts by mass ・Fischer-Tropsch wax (hydrocarbon wax, maximum endothermic peak temperature 90°C): 30 parts by mass 1 and Fischer-Tropsch wax to obtain a wax masterbatch.

<Production example of inorganic fine particles>
<Production example of inorganic fine particles 1>
After oxygen gas was supplied to the burner and the ignition burner was ignited, hydrogen gas was supplied to the burner to form a flame, and silicon tetrachloride as a raw material was added to the flame and gasified to obtain fine silica particles. . The obtained silica fine particles were transferred to an electric furnace, spread in a thin layer, and then heat-treated at 900° C. for sintering. After that, as a hydrophobizing treatment, the inorganic fine particles 1 were obtained by performing a surface treatment with hexamethyldisilazane. Table 1 shows the physical properties of the inorganic fine particles 1.

<Production example of inorganic fine particles 2 to 5>
Inorganic fine particles 2 to 5 were obtained by adjusting the amount of silicon tetrachloride, the amount of oxygen gas, the amount of hydrogen gas, silica concentration, residence time, sintering conditions, and surface treatment agent. Table 1 shows the physical properties of the inorganic fine particles 2 to 5.

<Production example of inorganic fine particles 6>
Metatitanic acid obtained by the sulfuric acid method was deironized and bleached, then adjusted to pH 9.0 with an aqueous sodium hydroxide solution, desulfurized, neutralized to pH 5.8 with hydrochloric acid, filtered and washed with water. Water was added to the washed cake to obtain a slurry of 1.5 mol/L as TiO ₂ , and then hydrochloric acid was added to adjust the pH to 1.5 for deflocculation.

The desulfurized and deflocculated metatitanic acid was collected as TiO ₂ and put into a reaction vessel with a volume of 3 L. An aqueous strontium chloride solution was added to the peptized metatitanic acid slurry so that the SrO/TiO ₂ molar ratio (ratio between the number of moles of SrO and the number of moles of TiO ₂ ) was 1.15, and then the TiO ₂ concentration was adjusted to 0.15. Adjusted to 8 mol/L. Next, after heating to 90° C. while stirring and mixing, 444 mL of a 10N (mol/L) sodium hydroxide aqueous solution was added over 50 minutes while performing micro-bubbling of nitrogen gas at 600 mL/min. After that, stirring was performed at a temperature of 95° C. for 1 hour while performing micro-bubbling of nitrogen gas at 200 mL/min.

After that, the reaction slurry was stirred while cooling water at 10° C. was flown through the jacket of the reaction vessel, and was rapidly cooled to 15° C. Hydrochloric acid was added until the pH reached 2.0, and stirring was continued for 1 hour. After washing the resulting precipitate by decantation, 6N (mol/L) hydrochloric acid is added to adjust the pH to 2.0, 8.0% by mass of n-octylethoxysilane is added to the solid content, and the mixture is stirred for 18 hours. did After neutralization with a 4N (mol/L) sodium hydroxide aqueous solution and stirring for 2 hours, filtration and separation were carried out, and the inorganic fine particles 6 were obtained by drying in the air at 120° C. for 8 hours. The average primary particle size calculated on a number basis by electron microscope observation was 40 nm.

<Toner Production Example 1>
Amorphous resin A 100 parts by mass Crystalline resin B 5 parts by mass Wax masterbatch 20 parts by mass C.I. I. Pigment Blue 15:3 5 parts by mass Using a Henschel mixer (FM-75 type, manufactured by Mitsui Mining Co., Ltd.), the raw materials shown in the above formulation were mixed at a rotation speed of 1200 rpm for a rotation time of 5 minutes, and then the temperature was 125 ° C. It was kneaded with a twin-screw kneader (PCM-30 type, manufactured by Ikegai Co., Ltd.) set to . The resulting kneaded product was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized product. The coarsely crushed material obtained was finely pulverized with a mechanical pulverizer (T-250, manufactured by Freund Turbo Co., Ltd.). Further, classification was performed using a rotary classifier (F-300, manufactured by Hosokawa Micron Corporation), and toner base particles 1 were obtained. The obtained toner base particles 1 had a weight average particle diameter (D4) of 6.0 μm.

・Toner base particles 1: 100 parts by mass ・Inorganic fine particles 3: 2 parts by mass ・Inorganic fine particles 6: 2 parts by mass The raw materials shown in the above formulation are mixed with a Henschel mixer (FM-10C model, manufactured by Mitsui Mining Co., Ltd.) at a rotational speed of After mixing at 3,000 rpm for a rotation time of 3 minutes, a heat treatment was performed using the surface treatment apparatus shown in FIG.
The operating conditions were feed rate = 5 kg/hr, hot air temperature = 180°C, hot air flow rate = 6 m ³ /min, cold air temperature = -5°C, cold air flow rate = 4 m ³ /min, cold air absolute water content = 3 g/m ³ , blower. Air volume = 20 m ³ /min, injection air flow rate = 1 m ³ /min.
Next, the obtained toner particles 1 and inorganic fine particles were mixed and stirred under the following conditions.

・Toner particles 1 100 parts by mass ・Inorganic fine particles 1 0.6 parts by mass ・Inorganic fine particles 3 2 parts by mass The raw materials shown in the above formulation are rotated using a Henschel mixer (FM-10C type, manufactured by Mitsui Mining Co., Ltd.). Toner 1 was obtained by mixing at several 4000 rpm and a rotation time of 2 minutes. The obtained toner 1 had an average circularity of 0.964 and a weight average particle diameter (D4) of 6.0 μm. Table 3 shows the summary and physical properties of Toner 1 obtained.

<Toner Production Examples 2 to 36>
As shown in Table 2, Toners 2 to 36 were produced in the same manner as in Toner Production Example 1, except that the type of material, number of parts added, mixing conditions, and heat treatment conditions were changed. Table 3 shows the properties of toners 2-36.

<Production example of magnetic core particles>
Step 1 (weighing/mixing step):
・_{Fe2O3 60.2} % by mass
・_MnCO3 33.9% by mass
・Mg(OH) ₂ 4.8% by mass
・ SrCO ₃ 1.1% by mass
The ferrite raw materials were weighed so as to obtain the mixing ratio as described above. After that, it was pulverized and mixed for 2 hours in a dry ball mill using zirconia balls (10 mm in diameter).

Step 2 (temporary firing step):
After being pulverized and mixed, the mixture was fired in the atmosphere at a temperature of 1,000° C. for 3 hours using a burner-type firing furnace to prepare a calcined ferrite. The composition of ferrite is as follows.
( _MnO ) _a (MgO) _b (SrO) _c ( _Fe2O3 ) _d
In the above formula, the values of a, b, c and d are as follows.
a=0.39, b=0.11, c=0.01, d=0.50

Step 3 (pulverization step):
After pulverizing to about 0.5 mm with a crusher, 30 parts by mass of water was added to 100 parts by mass of calcined ferrite using zirconia balls (10 mm in diameter), and pulverized for 2 hours with a wet ball mill.
The slurry was pulverized with a wet bead mill using zirconia beads (1.0 mm in diameter) for 4 hours to obtain a ferrite slurry.

Step 4 (granulation step):
To the obtained ferrite slurry, 2.0 parts by mass of polyvinyl alcohol is added as a binder to 100 parts by mass of calcined ferrite, and a spray dryer (manufacturer: Ogawara Kakoki Co., Ltd.) is used to form spherical particles having a diameter of about 36 μm. Granulated into particles.

Step 5 (main firing step):
In order to control the firing atmosphere, firing was performed in an electric furnace at a temperature of 1,150° C. for 4 hours under a nitrogen atmosphere (oxygen concentration of 1.00% by volume or less).

Step 6 (sorting step):
After the agglomerated particles were pulverized, they were sieved using a sieve with an opening of 250 μm to remove coarse particles to obtain magnetic core particles.

<Production example of coating resin>
・Cyclohexyl methacrylate monomer 26.8 parts by mass ・Methyl methacrylate monomer 0.2 parts by mass ・Methyl methacrylate macromonomer 8.4 parts by mass (a macromonomer having a methacryloyl group at one end and a weight average molecular weight of 5,000)
Toluene 31.3 parts by mass Methyl ethyl ketone 31.3 parts by mass The above materials were added to a four-necked separable flask equipped with a reflux condenser, thermometer, nitrogen inlet tube and stirring device, and nitrogen gas was introduced. to create a nitrogen atmosphere. Thereafter, the mixture was heated to 80° C., 2.0 parts by mass of azobisisobutyronitrile was added, and the mixture was refluxed for 5 hours for polymerization. Hexane was injected into the resulting reaction product to precipitate the copolymer, and the precipitate was separated by filtration and dried under reduced pressure to obtain a coating resin.

<Manufacturing Example of Magnetic Carrier 1>
・Coating resin 20.0% by mass
・Toluene 80.0% by mass
The above materials were dispersed and mixed in a bead mill to obtain a resin liquid.
100 parts by mass of the magnetic core particles were put into the Nauta mixer, and then the resin liquid was put into the Nauta mixer so that the resin component was 2.0 parts by mass. The mixture was heated to a temperature of 70° C. under reduced pressure, mixed at 100 rpm, and the solvent removal and coating operations were performed over 4 hours. Thereafter, the obtained sample was transferred to a Julia mixer, heat-treated at a temperature of 100° C. for 2 hours in a nitrogen atmosphere, and then classified using a sieve with an opening of 70 μm to obtain a magnetic carrier 1 . The obtained magnetic carrier had a volume distribution-based 50% particle diameter (D50) of 38.2 μm.
The above toners 1 to 36 and the magnetic carrier 1 were mixed with a V-type mixer (V-10 type: Tokuju Seisakusho Co., Ltd.) at 30 rpm for a rotation time of 5 so that the toner concentration was 8.0% by mass. Two-component developers 1 to 36 were obtained by mixing in minutes.

<Example 1>
As an image forming apparatus, a modified digital commercial printing printer imageRUNNER ADVANCE C5560 manufactured by Canon Inc. was used, and a two-component developer 1 was put into the developing device at the cyan position to evaluate the cleanability.
Here, the amount of discharge current (ΔIac) in the primary charging step was set to 100 μA.

[Calculation of discharge current amount ΔIac]
Here, the calculation of the amount of discharge current ΔIac flowing from the charging roller to the photosensitive member will be described.
In this example, a charging bias in which a DC bias is superimposed on a sinusoidal AC bias is used, and the AC charging current Iac flowing through the charging roller is controlled to be a constant current.
It may be considered that the impedance Zc between the charging roller and the photoreceptor is represented by the equivalent circuit of FIG. Rc is the resistance of the charging roller, Cc is the electrostatic capacity of the charging roller, Cd is the electrostatic capacity of the photoreceptor, and Cair is the electrostatic capacity of the minute air gap between the charging roller and the photoreceptor.

When no discharge occurs, the following relational expression (1) holds between the applied AC voltage Vac (maximum amplitude value; Vpp) and the charging AC current Iac according to the impedance Zc.
Iac=Iz Relational expression (1)
Iz=α・Vac, α=1/(√2・Zc)
However, when discharge occurs, that is, when the following relational expression (2) holds, as shown in FIG. 4, the above relational expression (1) does not hold and Iac>Iz. .
Vac(Vpp)≧Vth(V) Relational expression (2)
Vth: Discharge start voltage Here, Iz indicates a portion where Iac extends linearly (Vac<Vth) and its extrapolated portion (dotted line in FIG. 4 for Vac≧Vth).
In the description of this example, the difference ΔIac between Iac and Iz is defined as the amount of discharge current (μA).

The photosensitive drum used had a taper wear amount of 0.4 mg. A Taber abrasion test was performed as follows. A sample is mounted on a sample stage of a Taber abrasion tester (YSS Taber manufactured by Yasuda Seisakusho Co., Ltd.). Then, a load of 500 g was applied to each rubber wear wheel (CS-0) with wrapping tape (product name: C2000, manufactured by Fuji Film Co., Ltd.) attached to the two surfaces, and the weight of the sample after 1,000 rotations was reduced. was measured with a precision balance.

A photosensitive drum having a 10-point average surface roughness Rz of 0.8 μm and an average interval Sm of unevenness on the surface of 45 μm was used. The surface roughness of the photosensitive drum was measured using a contact-type surface roughness measuring machine (trade name: Surfcorder SE3500, manufactured by Kosaka Laboratory Ltd.) as follows.
Detector: R2 μm, 0.7 mN diamond needle, filter: 2CR, cutoff value: 0.8 mm, measurement length: 2.5 mm, feed rate: 0.1 mm, 10 points defined by JIS standard B0601 Data were processed for average roughness Rz. The average interval Sm between surface irregularities is an arithmetic mean value obtained by substituting the following Smi values obtained by measurement under the same conditions into the following equation.

A roughening means for controlling the surface shape of the photosensitive drum includes, but is not limited to, a polishing sheet, a discharge abrasive, and the like.
Evaluation of cleanability was performed as follows.

<Evaluation of cleanability>
Test environment: temperature 30°C, relative humidity 80%
Cleaning blade setting angle: 20°
Amount of toner applied to photosensitive drum: 0.3 to 0.4 mg/cm ²
Charge amount of toner: 20 to 30 μC/g
Under the above conditions, untransferred toner equivalent to 10 sheets of A3 paper was supplied to the cleaning blade at a process speed of 260 mm/sec, and then was clamped, and the amount of toner that passed through the cleaning blade (hereinafter also referred to as the amount of toner passed through) was measured. bottom. The amount of toner passing through was measured using a spectral densitometer ("504 spectral densitometer" manufactured by X-Rite Co., Ltd.). "Bachi-dome" means to momentarily stop the operation of the main body.
The linear pressure of the cleaning blade against the photosensitive drum was 10 gf/cm.

Evaluation criteria are as follows. Table 4 shows the evaluation results.
A: less than 0.01 B: 0.01 or more and less than 0.02 C: 0.02 or more and less than 0.04 D: 0.04 or more If it is C rank or higher, the level at which the effect of the present invention is obtained do.

<Transferability evaluation>
As an image forming apparatus, a modified digital commercial printing printer imageRUNNER ADVANCE C5560 manufactured by Canon Inc. was used, and two-component developer 1 was put into the developing device at the cyan position to evaluate the cleaning property. In order to evaluate under severe conditions, transfer performance was evaluated with the toner degraded in durability.
Durability conditions are as follows.
Paper: CS-680 (68.0 g/m ² )
(Sold by Canon Marketing Japan Inc.)
Amount of toner applied on photoreceptor: 0.35 mg/cm ² (FFh image, solid image)
Test environment: temperature 30°C, relative humidity 80%

As a durable image output test, 50,000 sheets of A4 paper were output using a band chart of FFh output with an image ratio of 0.1%.
Paper with a Bekk smoothness of 15 to 20 degrees (Hammer Mill Great White, LTR size, grammage 75 g/m ² , only paper with low smoothness was extracted) was used as low smoothness paper for evaluation of transferability. As an image for evaluation, an image of 10 cm ² was arranged in the center of the above A4 paper, the amount of toner applied on the photoreceptor was set to 0.35 mg/cm ² (FFh image), and the image density after output was measured. .
Transferability was evaluated based on the density difference between the image density before the durable image output test and the image density after the test. The image density was measured using a spectral densitometer (“504 spectral densitometer” manufactured by X-Rite Co., Ltd.).

Evaluation criteria are as follows. Table 4 shows the evaluation results.
A: Density difference is less than 0.10 B: Density difference is 0.10 or more and less than 0.15 C: Density difference is 0.15 or more and less than 0.25 D: Density difference is 0.25 or more Rank C or higher If there is, it is defined as a level at which the effects of the present invention are obtained.

<Examples 2 to 22 and Comparative Examples 1 to 14>
Evaluation was performed in the same manner as in Example 1, except that two-component developers 2 to 36 were used. Table 4 shows the evaluation results.

1. Raw material constant supply means2. Compressed gas flow rate adjusting means3. Introductory tube 4 . Protrusive member 5 . supply pipe6. processing chamber 7 . Hot air supply means8. Cool air supply means 9 . regulatory means 10 . collection means 11 . Hot air supply means outlet 12 . distribution member 13 . Pivoting member 14 . Powder particle supply port 2-1. Photoreceptor 2-2. cleaning blade 2-3. Blade nip portion 2-4. Lubricating layer made of small-sized inorganic fine particles 2-5. Blocking layer made of large-sized inorganic fine particles 2-6. Retention layer due to toner

Claims (4)

A toner comprising toner particles containing a binder resin and a colorant and inorganic fine particles coating the toner particles,
In the number distribution of the particle size of the primary particles of the inorganic fine particles on the surface of the toner particles,
A ₁ is the number of inorganic fine particles having a particle size in the range of 5 nm or more and 200 nm or less,
B ₁ is the number of inorganic fine particles present in a particle size range of 5 nm or more and 20 nm or less,
C ₁ is the number of inorganic fine particles having a particle diameter in the range of 35 nm or more and 55 nm or less,
When the number of inorganic fine particles present in the range of 80 nm or more and 135 nm or less in particle size is defined as _D1 , the relationships of the following formulas (1) to (5) are satisfied,
0.95≦A ₁ /Number of all inorganic fine particles Formula (1)
0.20≦B ₁ /A ₁ ≦0.50 Formula (2)
0.15≦C ₁ /A ₁ ≦0.55 Formula (3)
0.15≦D ₁ /A ₁ ≦0.55 Formula (4)
0.70≦(B ₁ /A ₁ +C ₁ /A ₁ +D ₁ /A ₁ ) Equation (5)
a coverage of the inorganic fine particles with respect to the toner particles is 55% or more;
In the number distribution of the particle size of the primary particles of the inorganic fine particles on the surface of the toner particles after the toner is washed with water,
A ₂ is the number of inorganic fine particles having a particle diameter in the range of 5 nm or more and 200 nm or less,
B ₂ is the number of inorganic fine particles having a particle size in the range of 5 nm or more and 20 nm or less,
C ₂ is the number of inorganic fine particles having a particle diameter in the range of 35 nm or more and 55 nm or less,
When the number of inorganic fine particles having a particle size of 80 nm or more and 135 nm or less is defined as _D2 , the relationships of the following formulas (6) to (8) are satisfied,
B ₂ /B ₁ ≦0.5 Formula (6)
0.85≦C ₂ /C ₁ formula (7)
0.55≦D ₂ /D ₁ ≦0.75 Formula (8)
In the water washing treatment, a dispersion of the toner added to deionized water containing a surfactant is shaken for 5 minutes under the conditions of a shaking speed of 46.7 cm/sec and a shaking width of 4.0 cm. A toner characterized by: The particle size distribution of the inorganic fine particles having a particle size in the range of 5 nm or more and 200 nm or less is
2. The toner according to claim 1, wherein peaks are present in each of the particle size range of 5 nm to 20 nm, the particle size range of 35 nm to 55 nm, and the particle size range of 80 nm to 135 nm. the inorganic fine particles having a particle size in the range of 5 nm or more and 20 nm or less are silica fine particles;
the inorganic fine particles having a particle size in the range of 35 nm or more and 55 nm or less are silica fine particles or strontium titanate fine particles;
3. The toner according to claim 1, wherein the inorganic fine particles having a particle size of 80 nm or more and 135 nm or less are silica fine particles. A method for producing a toner having toner particles containing a binder resin and a colorant and inorganic fine particles coating the toner particles,
a toner base particle producing step for producing toner base particles containing a binder resin and a colorant;
1.0 to 5.0 parts by mass of inorganic fine particles having a primary particle size of 35 nm or more and 55 nm or less with respect to 100 parts by mass of the toner base particles;
External addition step of externally adding 1.5 to 6.0 parts by mass of inorganic fine particles having a primary particle size of 80 nm or more and 135 nm or less;
a heat treatment step of treating the toner particles to which the inorganic fine particles are externally added with hot air;
0.3 to 2.0 parts by mass of inorganic fine particles having a primary particle size of 5 nm or more and 20 nm or less per 100 parts by mass of the heat-treated toner particles;
External addition step of externally adding 0.5 to 4.0 parts by mass of inorganic fine particles having a primary particle size of 80 nm or more and 135 nm or less;
4. The method for producing a toner according to any one of claims 1 to 3, characterized in that it has in this order.

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