JP2022039975A - Toner and method for producing toner - Google Patents

Abstract

To provide a toner which can have excellent low temperature fixability even under low temperature environment, and can have excellent development properties even in image output after having been left for a long time under high temperature and high humidity environment.SOLUTION: A toner contains toner particles containing a resin component and a wax, and inorganic fine particles on the surface of the toner particles, in which in cross section observation of the toner particles, a domain containing the wax is observed, when the domain having a major axis of 10-300 nm in the observed domains is represented by a domain S, and an occupancy area of the domain S in a region to 600 nm from the surface of the toner particles is represented by R1, the R1 is 3.0-15.0%, the inorganic fine particles contain fine particles A, volume resistivity of the fine particles A is 1.0×103 to 3.0×105 Ω cm, and a relative dielectric constant εr of the fine particles A is 100 or more.SELECTED DRAWING: None

Description

The present disclosure relates to toners used in electrophotographic image forming apparatus.

In recent years, there has been an increasing demand for power saving in electrophotographic image forming devices. In order to meet the demand for power saving, a toner having excellent low temperature fixability that can be fixed to a medium such as paper even at a low temperature is being studied.

A method of lowering the glass transition temperature of the resin component of the toner is known for the purpose of improving the low temperature fixability of the toner. However, when the image is output in a low temperature environment, a part of the amount of heat required for fixing is easily transferred to the paper or the atmosphere, and it is difficult to give a sufficient amount of heat to the toner. As a result, a higher fixing temperature is required for fixing the toner, so that fixing at a low temperature tends to be difficult. On the other hand, if the glass transition temperature of the resin component of the toner is lowered too much, the storage stability of the toner with respect to heat deteriorates, so that a method for further improving the low temperature fixability of the toner is required.

Therefore, for the purpose of improving the low-temperature fixability of the toner, a toner in which the entire toner particles are easily melted at the time of fixing by making it easy to melt the vicinity of the surface of the toner particles has been studied. Patent Documents 1 and 2 propose toners in which wax is unevenly distributed near the surface of toner particles. Since the wax is unevenly distributed near the surface of the toner particles, it is considered that the wax can easily melt the resin near the surface of the toner particles at the time of fixing, and excellent low temperature fixing property is obtained even when image output is performed in a low temperature environment. Can have.

Japanese Unexamined Patent Publication No. 2016-62041 Japanese Unexamined Patent Publication No. 2016-224248

However, as a result of studies by the present inventors on the toners described in Patent Documents 1 and 2, the developability tends to decrease when the image forming apparatus is left for a long time and then the image is output in a high temperature and high humidity environment. I understood. Specifically, it was found that the non-image portion of the fixed image is likely to be contaminated.

One aspect of the present disclosure provides a toner that can have excellent low-temperature fixability even in a low-temperature environment and can also have excellent developability in image output after being left in a high-temperature and high-humidity environment for a long time. It is a thing.

One aspect of the present disclosure is a toner containing toner particles containing a resin component and wax, and inorganic fine particles on the surface of the toner particles.
In observing the cross section of the toner particles,
The domain containing the wax was observed and
When the domain having a major axis of 10 to 300 nm among the observed domains is defined as domain S and the occupied area ratio of the domain S in the region from the surface of the toner particles to 600 nm is R1, the R1 is 3.0. ~ 15.0%,
The inorganic fine particles contain fine particles A, and the inorganic fine particles contain fine particles A.
The volume resistivity of the fine particles A is 1.0 × 10 ³ to 3.0 × 10 ⁵ Ω · cm.
The toner is characterized in that the relative permittivity εr of the fine particles A is 100 or more.

According to the present disclosure, it is possible to provide a toner that can have excellent low temperature fixability even in a low temperature environment and can have excellent developability even in image output after being left in a high temperature and high humidity environment for a long time.

It is a schematic diagram of the cross section of the toner particle for demonstrating the assumed mechanism which exerts the effect of this disclosure. It is the schematic of the rotating body which can be used in the mixing apparatus used in the external addition process of this disclosure. It is the schematic of the rotating body which can be used in the mixing apparatus used in the external addition process of this disclosure.

Unless otherwise specified, the description of "○○ or more and XX or less" and "○○ to XX" indicating a numerical range means a numerical range including a lower limit and an upper limit which are end points.

When numerical ranges are described step by step, the upper and lower limits of each numerical range can be arbitrarily combined.

In the present disclosure, the wax domain means a domain containing wax, and the minute wax domain means a wax domain having a major axis of 10 to 300 nm.

In the cross-sectional observation of the toner particles, the region from the surface of the toner particles to 600 nm is a region between the contour line corresponding to the surface of the toner particles and the contour line reduced by a distance 600 nm inside the contour line. Means.

The region near the surface of the toner particles means a region from the surface of the toner particles to the inside of 600 nm.

<Causes that easily contaminate non-image areas and the background to the invention>
The present inventors explain the reason why the non-image portion of the fixed image is likely to be contaminated when the image is output after being left for a long time in a high temperature and high humidity environment using the toner according to Patent Documents 1 and 2. I'm guessing.

Toner particles in which minute wax domains are dispersed near the surface of the toner particles tend to be toner having excellent low temperature fixability. This is because the area of contact between the dispersed wax and the resin near the surface of the toner particles is large, and the wax and the resin are compatible with each other at the time of fixing, so that the resin near the surface of the toner particles is generated with a small amount of heat. The present inventors believe that this is because it is easy to melt. Further, as the resin near the surface of the toner particles is melted with a small amount of heat, the entire toner particles are easily melted quickly. It can be said that this is an advantageous characteristic in an electrophotographic image forming apparatus having a high process speed because the temperature at the time of fixing can be lowered.

However, it is presumed that the amount of charge in the toner particles tends to be non-uniform in the toner particles in which minute wax domains are dispersed near the surface of the toner particles. If the charge amount in the toner particles is non-uniform, the charge distribution of the entire toner tends to be broad, and toner having a charge amount deviating from the range of the charge amount suitable for development tends to be generated. It is considered that such toner tends to adhere not only to the image portion in the fixed image but also to the non-image portion, and as a result, the non-image portion is likely to be contaminated.

The reason why the charge amount in the toner particles according to Patent Documents 1 and 2 tends to be non-uniform is that there is a difference in the charge amount between the portion where the wax is present near the surface of the toner particles and the portion where the wax is not present. The present inventors speculate that this is because the above is likely to occur.

Further, it was found that the above-mentioned problems remarkably appear in the image output after being left for a long time in a high temperature and high humidity environment. The present inventors speculate that this is partly because the amount of charge on the surface of the toner particles is affected by the amount of water in the atmosphere.

As a result of further studies based on such consideration, the toner containing the fine particles A having the following volume resistivity and relative permittivity on the surface of the toner particles has a minute wax in the vicinity of the surface of the toner particles. Nevertheless, it was found that it is difficult to contaminate the non-image part of the fixed image.

Volume resistivity of fine particles A: 1.0 × 10 ³ to 3.0 × 10 ⁵ Ω ・ cm
Relative permittivity εr of fine particles A: 100 or more <Assumed mechanism for exhibiting the effects of the present disclosure>
The assumed mechanism by which the toner having the above configuration exerts the effect of the present disclosure will be described with reference to FIG.

FIG. 1 is an example of a schematic cross-sectional view of the toner particles according to the present disclosure.

In the region (region near the surface) from the contour line 2 corresponding to the surface of the toner particles to the contour line 3 reduced by a distance inside 600 nm, the minute wax domain 1 occupies a specific ratio of the area. Further, the fine particles 5 (fine particles A) are contained in the vicinity of the portion where the wax domain exists in the vicinity of the surface of the toner particles.

In the toner having this configuration, it is considered that minute wax domains 1 are easily dispersed in the region near the surface of the toner particles, and the resin near the surface of the toner particles is easily melted at the time of fixing. Therefore, the toner has excellent low temperature fixing property. Is easy to obtain.

Further, when the toner is charged, the charge amount is considered to be different between the portion where the wax is present and the portion where the wax is not present in the region near the surface, so that the surface on the side where the charge amount is high and the electric field is strong It is considered that fine particles 5 (fine particles A) having a high relative permittivity are likely to be contained. Furthermore, the present inventors presume that the fine particles 5 (fine particles A) have a medium volume resistivity, so that an appropriate amount of charge can easily escape from a portion having a high charge amount and the charge distribution tends to be sharp. is doing. FIG. 1 is an example in which the portion where the wax is present near the surface of the toner particles has a stronger electric field.

As a specific example of the fine particles A in the present disclosure, a toner containing inorganic fine particles containing strontium titanate on the surface of the toner particles is one of the aspects of the present disclosure.

<Wax>
<Occupied area ratio of minute wax domains near the surface of toner particles>
In the cross-sectional observation of the toner particles, when the wax domain having a major axis of 10 to 300 nm is defined as the domain S and the occupied area ratio of the domain S in the region from the surface of the toner particles to 600 nm is R1, R1 is It is 3.0 to 15.0%. The present inventors speculate that a wax domain having a major axis smaller than 10 nm is too small in size to contribute to improving the low temperature fixability of the toner.

When R1 is 3.0% or more, it is easy to obtain a toner having excellent low temperature fixability. Therefore, R1 is 3.0% or more, more preferably 5.0% or more. Further, when R1 is 15.0% or less, it is difficult to excessively melt the resin component near the surface of the toner particles, and it is easy to obtain a toner having excellent heat-resistant storage stability. Therefore, R1 is 15.0% or less, preferably 12.0% or less, more preferably 10.0% or less, and even more preferably 9.0 or less.

Further, in the cross-sectional observation of the toner particles, when the occupied area ratio of all the wax domains in the region from the surface of the toner particles to 600 nm is R2, the R2 is preferably 3.0 to 25.0%. .. When R1 is 3.0 to 15.0% and R2 is within the above range, the toner has excellent low-temperature fixability and inorganic fine particles including fine particles A are difficult to be embedded in the surface of the toner particles. Is presumed to be easy to obtain. It is more preferably 3.0 to 20.0%, and even more preferably 3.0 to 15.0%.

The occupied area ratio of the wax domain in the region from the surface of the toner particles to the inside of 600 nm means the ratio of the area of the domain to the area of the region from the surface of the toner particles to the inside of 600 nm.

<Number of minute wax domains near the surface of toner particles>
In the cross-sectional observation of the toner particles, it is preferable that the number of the domains S in the region from the surface of the toner particles to 600 nm is 100 or more. When the number of the domains S is 100 or more, it is presumed that the resin near the surface of the toner particles is easily melted at the time of fixing, so that a toner having excellent low temperature fixing property can be easily obtained. Therefore, the number is preferably 100 or more, more preferably 150 or more, and further preferably 200 or more. The upper limit is not particularly limited from the viewpoint of low-temperature fixability, but is preferably 350 or less, and more preferably 300 or less, from the viewpoint of heat-resistant storage.

<Number of wax domains near the surface of toner particles Average major axis>
In the cross-sectional observation of the toner particles, when the average major axis of the number of all wax domains in the region from the surface of the toner particles to 600 nm is A1, the A1 is preferably 30 to 150 nm. When A1 is 30 nm or more, a large amount of wax domains having an appropriate size are likely to be contained in the region near the surface of the toner particles, and a toner having excellent low temperature fixability can be easily obtained. Therefore, it is preferably 30 nm or more, more preferably 50 nm or more, and further preferably 70 nm or more. Further, when A1 is 150 nm or less, it is considered that the wax domain having an excessive size is unlikely to increase in the region near the surface, so that a toner having appropriate elasticity and heat storage stability can be easily obtained. Therefore, it is preferably 150 nm or less, preferably 120 nm or less, and even more preferably 100 nm or less.

The above R1, R2 and A1 can be controlled by the conditions for producing toner particles (particularly the cooling step and the annealing step) at the time of toner production, the conditions for the external addition process, the type of wax, and the amount of wax added. In order to keep the above R1, R2 and A1 within the above values, the step for microcrystallizing the wax contained in the toner particles and the microcrystals of the wax existing near the surface of the toner particles The present inventors speculate that a further step for crystallization is required.

Examples of the step for microcrystallizing the wax contained in the toner particles include a step described later, in which the toner particles are rapidly cooled and then annealed. This is because by rapidly cooling the toner particles, crystal nuclei of the wax contained in the toner particles are likely to be formed, and by subsequent annealing, the crystal growth of the crystal nuclei is promoted, so that minute particles are formed in the toner particles. It is considered that this is because the toner domain is easily formed.

Further, as a step for finely crystallizing the wax existing near the surface of the toner particles, there is a step of externally adding inorganic fine particles to the toner particles at a temperature at which the wax is likely to crystallize. It is presumed that by externally adding the inorganic fine particles to the toner particles at the temperature, the uncrystallized wax existing near the surface of the toner particles tends to form a large number of crystal nuclei due to the impact from the inorganic fine particles. Toner. As a result, it is considered that minute wax domains are likely to be formed near the surface of the toner particles.

<Type of wax>
It is preferable that the toner particles contain ester wax. Since the ester wax is considered to be easily compatible with the resin component, the resin component is easily melted at the time of fixing, and a toner having excellent low temperature fixability is easily obtained.

Since it is easy to obtain a toner having excellent low-temperature fixability, the ratio of the mass of the ester wax to the mass of the resin component contained in the toner particles is preferably 10.0 to 20.0% by mass.

The ester wax contained in the toner particles is not particularly limited, and the following ester waxes can be used.

Monofunctional ester waxes such as behenyl stearate, behenyl behenate, stearyl behenate; bifunctional ester waxes such as ethylene glycol distearate, dibehenyl sebacate, hexanediol dibehenate; glycerin tribehenate and the like. Functional ester waxes; Tetrafunctional ester waxes such as pentaerythritol tetrastearate and pentaerythritol tetrapalmitate; Hexofunctional ester waxes such as dipentaerythritol hexastearate and dipentaerythritol hexapalmitate; Polyglycerin behenate Polyfunctional ester waxes such as; natural ester waxes such as carnauba wax and rice wax.

Further, the toner particles may contain a wax other than the ester wax, such as a hydrocarbon wax.

<Wax content>
The content ratio of wax in the toner particles is preferably 5.0 to 25.0% by mass. When the wax is contained in the toner particles in the above ratio, it is easy to obtain a toner having excellent low temperature fixability and releasability. More preferably, the content ratio is 5.0 to 15.0% by mass.

<Inorganic fine particles>
<Particle A>
The inorganic fine particles contain the fine particles A, and the volume resistivity of the fine particles A is 1.0 × 10 ³ to 3.0 × 10 ⁵ Ω · cm. When the volume resistivity is 1.0 × 10 ³ Ω · cm or more, the charge charged on the surface of the toner particles does not easily escape excessively, and it is easy to obtain a toner having excellent chargeability and developability. Further, when the volume resistivity is 3.0 × ¹⁰⁵ Ω · cm or less, the amount of electric charge escaping from the toner particles is unlikely to be too small, and it is easy to obtain a toner having excellent developability.

Further, the relative permittivity εr of the fine particles A is 100 or more. When the relative permittivity εr is 100 or more, the fine particles A are likely to be contained in the portion of the surface of the toner particles where the amount of charge is high. Therefore, it is preferably 100 or more, more preferably 150 or more, and even more preferably 200 or more. The upper limit is not particularly limited, but is preferably 1000 or less, more preferably 500 or less, and even more preferably 300 or less. That is, a preferable range of the relative permittivity εr of the fine particles A is 100 or more and 300 or less.

The above-mentioned volume resistivity and relative permittivity can be controlled by the type of inorganic fine particles externally attached to the toner.

The fine particles A are preferably strontium titanate. Since strontium titanate has the above-mentioned volume resistance and relative permittivity and has high thermal conductivity, it is easy to transfer heat to the wax near the surface of the toner particles at the time of fixing, and it has excellent low-temperature fixing property. Easy to become toner.

The inorganic fine particles preferably contain other fine particles other than the above fine particles A.

Examples of other fine particles include silica fine particles. Examples of the silica fine particles include wet silica such as a sedimentation method and a sol-gel method, and dry silica such as an explosive combustion method and a fumed method. However, from the viewpoint of dispersibility on the surface of the toner particles, the silica fine particles are wet silica fine particles such as the sol-gel method. Is preferable.

Since it is easy to obtain a toner having excellent developability, the ratio of the mass of the inorganic fine particles to the mass of the toner particles is preferably 0.10 to 2.00 mass%. More preferably, it is 0.10 to 1.00% by mass.

Further, since it is easy to obtain a toner having excellent developability, the ratio of the mass of the fine particles A to the mass of the toner particles is preferably 0.10 to 1.00 mass%. More preferably, it is 0.15 to 0.25% by mass.

<Number average particle size of fine particles A>
When the number average particle size of the fine particles A is A2, it is preferable that A2 is 10 to 80 nm. When A2 is within the above range, the particle size of the fine particles A is sufficiently small and easily moves on the surface of the toner particles. As a result, when an electric field is applied to the toner, the fine particles A are likely to be present in the portion of the surface of the toner particles where the electric field is strong, which is preferable.

Further, since development streaks are less likely to occur in the fixed image, it is preferable that the number average major axis A1 of the wax domains near the surface of the toner particles and the number average particle size A2 of the fine particles A satisfy the following formula (1). ..
0.3 ≤ A2 / A1 ≤ 1.2 ... (1)

<Transition index of fine particles A>
The fine particles A preferably have a migration index of 3.5 to 6.5 with respect to the polycarbonate film, which is calculated by the following formula (2). The measurement method will be described later.
Transition index to the polycarbonate film = Area ratio of the fine particles A transferred to the polycarbonate film [X1] / Coverage ratio of the fine particles A on the surface of the toner particles [X2] × 100 ... (2)

The above-mentioned migration index is a value indicating the ease of migration of the fine particles A to the polycarbonate film, and the larger the value, the easier it is to disengage from the toner base and to migrate to other members. When the transition index is 3.5 or more, it is presumed that the adhesive force of the fine particles A to the toner particles is unlikely to be excessive, and the fine particles A are likely to be contained at a position on the surface of the toner particles where the electric field is strong. Further, when it is 6.5 or less, the adhesive force of the inorganic fine particles to the toner particles is unlikely to be excessive, and it is easy to obtain a toner having excellent fluidity.

The migration index of the above-mentioned inorganic fine particles can be controlled by the temperature at which the inorganic fine particles are externally added to the toner particles. The higher the temperature at the time of externalizing, the lower the transition index, and the lower the temperature at the time of externalizing, the higher the transition index.

<Weight average particle size of toner particles (D4)>
The weight average particle diameter (D4) of the toner particles is preferably 5.0 to 10.0 μm. When the weight average particle diameter (D4) of the toner particles is within the above range, the charge stability, fixability, and developability of the toner can be easily maintained. More preferably, the D4 of the toner particles is 5.0 to 9.0 μm.

The weight average particle diameter (D4) of the toner particles can be controlled by the pulverization conditions when the toner is produced by the pulverization method. Further, when the toner is produced in an aqueous medium, it can be controlled by the amount of the dispersion stabilizer, the rotation speed of the stirrer, or the like.

<Resin component>
The resin component is preferably a binder resin. That is, it is preferable that the toner particles contain a binder resin and a wax.

The resin contained in the resin component is not particularly limited, and for example, the following can be used.

Monopolymers of styrene such as polystyrene and polyvinyltoluene and their substitution products; styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalin copolymer, styrene-methyl acrylate copolymer, styrene- Ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-methyl methacrylic acid copolymer, styrene-methacrylic acid Ethyl acid acid copolymer, styrene-butyl methacrylic acid copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone Stylized polymers such as copolymers, styrene-butadiene copolymers, styrene-isoprene copolymers, styrene-maleic acid copolymers, styrene-maleic acid ester copolymers; polymethylmethacrylate, polybutylmethacrylate, Polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyester, polyamide resin, epoxy resin, polyacrylic acid resin. These can be used alone or in combination of two or more. Of these, a styrene acrylic resin such as a styrene-butyl acrylate copolymer is particularly preferable from the viewpoint of development characteristics, fixability and the like. Further, the content ratio of the styrene acrylic resin in the resin component is preferably 80.0 to 100.0% by mass.

<Styrene acrylic resin>
Examples of the polymerizable monomer corresponding to the monomer unit constituting the styrene acrylic resin include the following.

As the styrene-based polymerizable monomer, styrene; a styrene-based polymerizable monomer such as α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, and p-ethylstyrene.

As acrylic polymerizable monomers, methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, Acrylic-based polymerizable monomers such as n-octyl acrylate, dodecyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, cyclohexyl acrylate, and phenyl acrylate.

As methacrylic polymerizable monomers, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-hexyl methacrylate, dodecyl methacrylate, 2- Methyl-based polymerizable monomers such as ethylhexyl methacrylate, stearyl methacrylate, n-octyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, and diethylaminoethyl methacrylate.

Other monomers such as acrylonitrile, methacrylonitrile, and acrylamide can be mentioned.

The method for producing the styrene acrylic resin is not particularly limited. Further, the resin component may be used in combination with a resin other than the styrene acrylic resin.

<Polyester P>
The toner particles have a core containing a resin component and wax, and a shell covering the surface of the core, and the shell preferably contains a polyester P having a monomer unit represented by the following formula (3).

A toner containing a polyester having a monomer unit derived from isosorbide represented by the formula (3) makes it easy to obtain a toner having excellent developability. The present inventors speculate on this mechanism as follows.

Since wax is generally highly hydrophobic, it is considered that the portion where the wax is present near the surface of the toner particles has a small interaction with the moisture in the atmosphere. As a result, especially in a high humidity environment, a difference in the amount of charge is likely to occur between the wax and the portion where the wax does not exist near the surface of the toner particles.

On the other hand, the above-mentioned isosorbide-derived monomer unit has high water absorption, and the toner particles having a shell containing polyester P having the monomer unit have moisture in the atmosphere even in the portion where the wax is present near the surface. The interaction with is likely to be large. Therefore, it is considered that the non-uniformity of charge in the toner particles is easily alleviated. As a result, the present inventors speculate that it becomes easy to obtain a toner having excellent developability.

As a method for producing polyester, for example, a method using a dehydration condensation reaction from a carboxylic acid compound and an alcohol compound, or a transesterification reaction can be used. Examples of the catalyst include an acidic catalyst or an alkaline catalyst used in the esterification reaction. For example, zinc acetate, titanium compounds and the like can be mentioned.

Further, the alcohol component in the polyester P is preferably 43 to 57 mol%, and the carboxylic acid component in the polyester P is preferably 57 to 43 mol%.

Polyester is a resin composed of an alcohol component and a carboxylic acid component, and both components are exemplified below.

The alcohol components include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, and 1,6-hexane. Diol, neopentyl glycol, 2-ethyl-1,3-hexanediol, cyclohexanedimethanol, butenediol, octenediol, cyclohexenedimethanol, hydride bisphenol A, and bisphenol represented by the following formula (A) and derivatives thereof; Examples thereof include diols represented by the following formula (B).

(In the formula (A), R is (-CH ₂ -CH _2- ) or (-CH ₂ -CH ₂ -CH _2- ). X and y are integers of 1 or more, respectively, and x + y. The average value is 2 to 10.)

(In the formula (B), R'is one of the above (B1) to (B3). X'and y'are integers of 1 or more, and the average value of x'+ y'is 2. ~ 10.
It is preferable that the alcohol component of the polyester P contains bisphenol represented by the formula (A) and a derivative thereof. Further, it is more preferable that the average value of x + y in the formula (A) is 1 to 4. Further, it is more preferable that R in the formula (A) is (-CH ₂ -CH _2- ).

Similarly, the alcohol component of the polyester P preferably contains ethylene glycol.

Examples of the carboxylic acid component include phthalic acid, terephthalic acid, isophthalic acid, phthalic acid anhydride, diphenyl-PP'-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, and diphenylmethane. Benzenedicarboxylic acids such as -P.P'-dicarboxylic acid, benzophenone-4,4'-dicarboxylic acid, 1,2-diphenoxyetane-P.P'-dicarboxylic acid or anhydrides thereof; succinic acid, adipic acid. , Sevacinic acid, Azelaic acid, Glytaric acid, Cyclohexanedicarboxylic acid, Triethylenedicarboxylic acid, Alkyldicarboxylic acids such as malonic acid or anhydrides thereof; Examples thereof include unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, and itaconic acid, or anhydrides thereof.

Among the above, it is preferable that the carboxylic acid component of polyester P contains terephthalic acid.

In the present disclosure, the polyester P can be obtained by synthesizing from a dicarboxylic acid and a diol, but in some cases, a polycarboxylic acid or a polyol having a valence of 3 or more may be used.

The content ratio of polyester P in the resin component is preferably 0.1 to 10.0% by mass.

<Various additives>
If necessary, the toner may contain one or more additives selected from a colorant, a mold release agent, a magnetic substance, a charge control agent, a fluidizing agent, and the like. Various additives used in the toner will be specifically described.

<Colorant>
Examples of the black colorant include carbon black, a magnetic material, or a black colorant using the yellow, magenta, and cyan colorants shown below.

Examples of the yellow colorant include a monoazo compound, a disazo compound, a condensed azo compound, an isoindolinone compound, an anthraquinone compound, an azo metal complex, a methine compound, and an allylamide compound.

Examples of the magenta colorant include monoazo compounds, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds and perylene compounds.

Examples of the cyan colorant include a copper phthalocyanine compound and its derivative, an anthraquinone compound, and a basic dye lake compound.

<Magnetic material>
The toner may be a magnetic toner. That is, the toner particles may be magnetic toner containing a magnetic substance.

The magnetic material is mainly composed of magnetic iron oxide such as triiron tetraoxide and γ-iron oxide, and contains elements such as phosphorus, cobalt, nickel, copper, magnesium, manganese, aluminum and silicon. Can be mentioned. That is, the magnetic material contained in the toner particles is preferably iron oxide. The shape of the magnetic material includes a polyhedron, an octahedron, a hexahedron, a sphere, a needle, and a scaly shape. Preferred above. Further, the magnetic material is preferably a hydrophobized surface-treated magnetic material.

Further, the content ratio of the magnetic substance in the toner particles is preferably 25.0 to 45.0% by mass.

Further, it is preferable that the number average particle size of the magnetic material is 0.10 to 0.40 μm. When the number average particle size is 0.10 μm or more, the magnetic material itself is unlikely to become reddish black, so that a high-quality image can be easily obtained. On the other hand, when the number average particle size is 0.40 μm or less, the coloring power of the toner becomes good and it is easy to disperse the toner particles uniformly.

The average particle size of the magnetic material can be measured using a transmission electron microscope. Specifically, after sufficiently dispersing the toner to be observed in the epoxy resin, it is cured in an atmosphere at a temperature of 40 ° C. for 2 days to obtain a cured product. The obtained cured product is used as a flaky sample by a microtome, and the diameters of 100 magnetic powder particles in a visual field are measured with a photograph at a magnification of 10,000 to 40,000 times with a transmission electron microscope (TEM). Then, the number average particle diameter is calculated based on the equivalent diameter of the circle equal to the projected area of the magnetic powder. It is also possible to measure the particle size with an image analyzer.

<Charge control agent>
Examples of the load-electric charge control agent include the following.

Monoazo metal compounds, acetylacetone metal compounds. Aromatic oxycarboxylic acid, aromatic dicarboxylic acid, oxycarboxylic acid and dicarboxylic acid-based metal compounds. Aromatic oxycarboxylic acids, aromatic mono- and polycarboxylic acids, and their metal salts, anhydrides, esters. Phenolic derivatives such as bisphenol, urea derivatives, metal-containing salicylic acid-based compounds, metal-containing naphthoic acid-based compounds, boron compounds, quaternary ammonium salts, calix array, resin-based charge control agents.

Examples of the positive charge control agent include the following.

Nigrosine modified products such as niglosin and fatty acid metal salts; guanidine compounds; imidazole compounds; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and their analogs. Onium salts such as phosphonium salts and their lake pigments; triphenylmethane dyes and their lake pigments (as lake agents, phosphotung acid, phosphomolybdic acid, phosphotungene molybdic acid, tannic acid, lauric acid, erosion) Acids, ferricyanides, ferrocyanides, etc.); Metal salts of higher fatty acids; Diorganosin oxides such as dibutyltin oxide, dioctyltinoxide, dicyclohexyltinoxide; Diorganos such as dibutyltinborate, dioctyltinborate, dicyclohexyltinborate. Suzubolates; resin-based charge control agents can be mentioned.

These can be used alone or in combination of two or more.

Among the above, the metal-containing salicylic acid-based compound is preferable, and the metal thereof is more preferably aluminum or zirconium. More preferably, it is an aluminum salicylate compound.

Similarly, among the above, it is preferable to use a polymer or copolymer having a sulfonic acid group, a sulfonic acid base or a sulfonic acid ester group, a salicylic acid moiety, and a benzoic acid moiety.

The content of the charge control agent is preferably 0.01 parts by mass or more and 20.0 parts by mass or less, and more preferably 0.05 parts by mass or more and 10.0 parts by mass or less with respect to 100.0 parts by mass of the resin component. be.

<Toner manufacturing method>
The toner may be produced by any method such as a pulverization method, a suspension polymerization method, an emulsion aggregation method, and a dissolution suspension method, but the toner is not limited thereto. Since it is easy to control the presence state of the wax contained in the toner particles, it is preferably produced by a suspension polymerization method.

Further, as preferable steps of the manufacturing method for manufacturing the toner of the present disclosure, a cooling step and an annealing step are described below.

As the cooling step, it is preferable to perform a cooling step of lowering the temperature from the cooling start temperature to the cooling reaching temperature before sending the dispersion liquid of the toner particles for which the volatile component removing step is completed to the next step. It is considered that the easiness of forming crystal nuclei of wax domains in the toner particles can be controlled by the conditions of the cooling process. The cooling conditions are changed by changing the cooling start temperature, the cooling rate, and the cooling reaching temperature.

When the crystallization peak temperature of the wax is Ta, it is preferable that the method for producing the toner includes a holding step of holding the dispersion liquid of the toner particles in the above Ta + 15 (° C.) to the above Ta + 35 (° C.). It is presumed that having the step of holding the toner particles in the temperature range improves the fluidity of the wax in the toner particles and makes it easier to disperse the wax in the toner particles.

Further, it is preferable to have a cooling step of cooling the dispersion liquid that has undergone the above holding step from the cooling start temperature to the cooling reaching temperature at a cooling rate of 40.0 to 200.0 ° C./min.

It is presumed that when the cooling rate is within the above range, the crystallization of the wax accompanying cooling is sufficiently fast, and it becomes easy to form crystal nuclei of the wax domain in the toner particles. The cooling rate is more preferably 100.0 to 140.0 ° C./min.

The cooling start temperature is preferably Ta + 15 (° C.) to Ta + 35 (° C.), and the cooling ultimate temperature is preferably Ta-35 (° C.) to Ta-20 ° C. (° C.).

When the cooling start temperature is within the above range, the wax is easily melted in the toner particles, and the wax is easily dispersed in the entire toner particles, which is preferable.

When the cooling temperature reaches the above range, the wax in the toner particles crystallizes rapidly, so that it is considered that a large number of wax crystal nuclei are likely to be formed in the toner particles. Since a large number of crystal nuclei are formed, it is considered that the wax domains are likely to be suppressed from crystal growth and coalescence, and minute wax domains are likely to be formed.

It is preferable to perform an annealing step on the dispersion liquid that has undergone the cooling step in order to promote crystallization of the wax. In the annealing step, it is presumed that the wax is easily crystallized around the crystal nuclei formed in the cooling step.

The conditions of the annealing step can be determined by the annealing temperature and the annealing time. As for the annealing temperature and annealing time, it is preferable to hold the dispersion liquid at the above Ta-35 (° C.) to the above Ta-20 (° C.) for 30 minutes or more. Further, the time of the annealing step is preferably 150 minutes or less.

Further, the toner particles may be taken out from the dispersion liquid that has undergone the annealing step, and then the toner particles and the inorganic fine particles may be mixed at the Ta-35 (° C.) to the Ta-20 (° C.). preferable. By externally adding inorganic fine particles to the toner particles within the above temperature range, the uncrystallized wax existing near the surface of the toner particles can easily form a large number of crystal nuclei due to the impact from the inorganic fine particles. Guessed. As a result, the present inventors speculate that minute wax domains are likely to be formed near the surface of the toner particles. Further, the rotation speed at the time of mixing in the external addition step is preferably 1500 to 2500 rpm.

The toner produced through the above-mentioned manufacturing process is preferable because the above-mentioned R1 and A1 easily satisfy the above-mentioned preferable range.

That is, the toner manufacturing method is
(I) A step of forming particles containing a polymerizable monomer and a wax in an aqueous medium.
(Ii) A step of obtaining a dispersion liquid containing a resin component obtained by polymerizing the polymerizable monomer contained in the particles and toner particles containing a wax.
(Iii) Holding step of holding the dispersion liquid at the Ta + 15 (° C.) to the Ta + 35 (° C.) when the crystallization peak temperature of the wax is Ta (° C.) (iv) The dispersion liquid is held at the Ta + 15 (° C.). ) To the cooling step of cooling from the Ta + 35 (° C.) to the Ta-35 (° C.) to the Ta-20 (° C.) at a cooling rate of 40.0 to 200.0 ° C./min.
(V) An annealing step of holding the dispersion liquid that has undergone the cooling step at the Ta-35 (° C.) to the Ta-20 (° C.) for 30 minutes or longer.
(Vi) The toner particles taken out from the dispersion liquid which has undergone the annealing step, and (vii) the toner particles taken out in the taking-out step in the Ta-35 (° C.) to the Ta-20 (° C.). In addition, it has an external addition process for externally adding inorganic fine particles.
The inorganic fine particles contain fine particles A, and the inorganic fine particles contain fine particles A.
The volume resistivity of the fine particles A is 1.0 × 10 ³ to 3.0 × 10 ⁵ Ω · cm.
It is preferable to use a method for producing a toner in which the relative permittivity εr of the fine particles A is 100 or more.

When a plurality of types of wax are contained in the toner particles, the value of Ta is the crystallization peak temperature of the wax having the largest content ratio in the toner particles.

<Various measurement methods, etc.>
Hereinafter, various measurement methods and the like will be described.

<Measurement method of occupied area ratio of minute wax domain in the region near the surface of toner particles>
(1) Observation of cross section of toner by STEM To observe crystalline materials such as wax inside the toner, after preparing a section of toner, dye it with ruthenium tetroxide and observe STEM. By dyeing with ruthenium tetroxide, a contrast difference occurs between an amorphous resin such as a binder resin and a crystalline material such as wax during STEM observation. Therefore, it is possible to easily distinguish and observe crystalline materials such as wax.

First, the toner is dispersed in a visible light curable resin (trade name: Aronix LCR series D-800, manufactured by Toagosei Co., Ltd.), and then cured by irradiating with short wavelength light. The obtained cured product is cut out with an ultramicrotome equipped with a diamond knife to prepare a flaky sample of 250 nm.

Next, the cut out sample was magnified using a transmission electron microscope (trade name: electron microscope JEM-2800, manufactured by JEOL Ltd.) (TEM-EDX) at a magnification of 40,000 to 50,000 times, and toner particles were used. Obtain a cross-sectional image of.

The toner particles to be observed are selected as follows.

First, the cross-sectional area of the toner particles is obtained from the image of the cross section of the toner particles, and the diameter of a circle having an area equal to the cross-sectional area (circle equivalent diameter) is obtained. Only the image of the cross section of the toner particles in which the absolute value of the difference between the equivalent circle diameter and the weight average particle size (D4) of the toner particles is within 1.0 μm is observed.

(2) Binarization using image analysis software The wax domain portion of the TEM image is binarized using image analysis software. In this disclosure, binarization was performed using ImageJ, which is image analysis software. The binarization conditions are automatically determined by a discriminant analysis method that can be selected by selecting [Image]-[Adjust]-[Auto Threshold]-[Method: Otsu] in ImageJ. However, when a material with different brightness is observed in the cross-sectional observation of the toner particles, a histogram of the brightness of the image is calculated, the threshold value is determined by the discriminant analysis method, and the upper and lower parts of the region containing the wax domain are observed. Binarization is performed using the threshold value of.

As an example of measuring the occupied area ratio of the wax domain in a specific region in the cross-sectional observation of the toner particles, the measurement of the occupied area ratio of the wax domain and the average number of wax domains in the region from the surface of the toner particles to the inside 600 nm. Is described below.

The TEM image before binarization is reopened using ImageJ, and [Process]-[Find Edge] is selected to extract the outline of the toner. After selecting [centroid] from [Analyze]-[Set Measurements], select [Analyze]-[Analyze Particles] to obtain the position of the center of gravity of the toner particles, and determine the length from this position of the center of gravity to the contour of any toner. Ask. Select [Image]-[Scale] so that the length to the contour is shortened by 600 nm, and scale the image. The scaled image is superposed on the initially binarized image of the wax domain to mask the region above 600 nm from the surface of the toner particles.

(3) Measurement method of occupied area ratio R1 of wax domain having a major axis of 10 to 300 nm in the region from the surface of the toner particles to 600 nm (the region near the surface of the toner particles) After the above binarization operation is completed in Image J. , [Analyze]-[Set Measurements]-[Feret's Diameter] and [Area] are selected, then select [Analyze]-[Analyze Particles] to obtain the area and major axis of the wax domain, and the major axis is 10 nm or more and 300 nm. Calculate the total area of the following domains. In addition, the entire region inside 600 nm from the surface of the toner particles is binarized by using the toner particle contour extraction images before and after the reduction. The area of the region from the surface of the toner particles to 600 nm is selected by selecting [Analyze]-[Analyze Particles], and the occupied area ratio of the wax domain having a major axis of 10 nm or more and 300 nm or less is obtained.

The above operation is performed on a STEM cross-sectional image of 10 toner particles. The average value of the occupied area ratio of the obtained wax domains having a major axis of 10 nm or more and 300 nm or less is defined as R1, and the average value of the number of wax domains is defined as the number of wax domains. Further, from the major axis obtained above, the number average value A1 of the major axis of the wax domain can be calculated.

When the wax domain 4 straddles the contour line 3 in which the contour line is reduced by a distance of 600 nm inside from the contour line 2 of the toner particle cross section in the direction of the center of gravity as in the wax domain 4 in FIG. 1, the wax domain is not included in the region. And.

<Measurement method of relative permittivity / volume resistivity>
Relative permittivity and volume resistivity are values peculiar to a substance and can be calculated by the following measurements.

To measure the relative permittivity of fine particles, SI 1260 electrical interface (manufactured by Toyo Technica) is used as a power supply and ammeter, and 1296 digital interface (manufactured by Toyo Technica) is used as a current amplifier.

As the measurement sample, a sample obtained by heat-molding the sample into a disk shape having a thickness of 3.0 ± 0.5 mm using a tablet molding device is used. A gold electrode is produced in a circular shape having a diameter of 10 mm by using mask vapor deposition on the upper and lower surfaces of the sample.

A measurement electrode is attached to the prepared measurement sample, and an AC voltage having a peak voltage (Vp-p) of 100 mV is applied at a frequency of 0.1 MHz to measure capacitance and impedance. The relative permittivity εr and volume resistivity ρv of the measurement sample are calculated from the following formulas.
・ Εr = dC / ε ₀ S
・ Ρv = ZS / d
d: Thickness of the measurement sample (m)
C: Capacitance (F)
ε ₀ : Permittivity of vacuum (F / m)
S: Electrode area (m ² )
Z: Impedance (Ω)
<Measurement of average particle size A2 of the number of fine particles A contained on the surface of toner particles>
The number average particle size of the fine particles A is measured using a scanning electron microscope "S-4800" (manufactured by Hitachi High-Technologies Corporation). By observing the toner to which the inorganic fine particles are added, the major axis of 100 fine particles A is randomly measured in a field of view magnified up to 50,000 times to obtain the number average particle size. The observation magnification is appropriately adjusted according to the size of the inorganic fine particles. By specifying the circle-equivalent diameter and circularity of the fine particles A externally attached to the toner particles in advance and setting the values, only the number average particle size of the fine particles A can be extracted.

<Measurement method of migration index of fine particles A>
As a method for indexing the adhered state of the fine particles A, the amount of transfer of the fine particles A when the toner is brought into contact with the substrate is evaluated. As the material of the surface layer of the substrate, in the present disclosure, as the substrate simulating the surface layer of the photoconductor, a substrate using a polycarbonate resin as the surface layer material is used. Specifically, first, a bisphenol Z-type polycarbonate resin (trade name: Iupiron Z-400, manufactured by Mitsubishi Engineering Plastics Co., Ltd., viscosity average molecular weight (Mv): 40,000) is added to toluene at a concentration of 10% by mass. Dissolve to make a coating liquid.

This coating liquid is applied to an aluminum sheet having a thickness of 50 μm using a 50-count Meyer bar to form a coating film. Then, the coating film is dried at 100 ° C. for 10 minutes to prepare a sheet having a polycarbonate resin layer (thickness: 10 μm) on the aluminum sheet. Hold this sheet in the board holder. The substrate is a square with a side of about 3 mm.

Hereinafter, the measurement step will be described separately by dividing it into a step of arranging the toner on the substrate, a step of removing the toner from the substrate, and a step of quantifying the amount of fine particles A adhered to the substrate.

-Step of arranging the toner on the substrate The toner is contained in a porous flexible material (hereinafter referred to as "toner holder"), and the toner holder is brought into contact with the substrate. A sponge (trade name: White Wiper Marusan Sangyo Co., Ltd.) is used as the toner holder. The toner holder is fixed to the tip of a load meter fixed to a stage that moves in the direction perpendicular to the contact surface of the substrate so that the toner holder and the substrate can contact each other while measuring the load. For the contact between the toner holder and the substrate, the step of moving the stage, pressing the toner holder against the substrate until the load meter shows 10N, and then separating the toner holder is one step, and this step is repeated 5 times.

-Step of removing toner from the substrate Bring an elastomer suction port with an inner diameter of about 5 mm connected to the tip of the nozzle of the vacuum cleaner close to the substrate after contacting the toner holder so that it is perpendicular to the toner placement surface. Remove the toner adhering to the substrate. At this time, remove the toner while visually checking the degree of residual toner. The distance between the end of the suction port and the substrate is 1 mm, the suction time is 3 seconds, and the suction pressure is 6 kPa.

-Step to quantify the amount of fine particles A attached to the substrate When quantifying the amount and shape of fine particles A remaining on the substrate after removing the toner, observation with a scanning electron microscope and image measurement are used. .. First, platinum is sputtered on the substrate after removing the toner under the conditions of a current of 20 mA and 60 seconds to prepare a sample for observation. Using the above scanning electron microscope, observation was performed with a reflected electron image obtained from the observation sample. The observation magnification was 50,000 times, the acceleration voltage was 10 kV, and the working distance was 3 mm. In the image obtained by observation, the inorganic fine particles are represented by high brightness and the substrate is represented by low brightness, so that the amount of fine particles A in the visual field can be quantified by binarization. The binarization conditions are automatically determined by the discriminant analysis method included in ImageJ's [Auto Threshold]. In the present disclosure, Image J, which is image analysis software, is used for binarizing the observed image. The area ratio of the fine particles A in the observation visual field is obtained by integrating only the area of the fine particles A with Image J and dividing by the area of the entire observation visual field. By specifying the circle-equivalent diameter and circularity of the fine particles A externally attached to the toner particles in advance and setting the values, only the area of the fine particles A can be extracted. The above measurement is performed on 100 binarized images, and the average value is defined as the area ratio [X1] (unit: area%) of the fine particles A on the substrate.

Next, the coverage [X2] (unit: area%) of the fine particles A on the toner particles is calculated. The coverage of the fine particles A is measured by using the above-mentioned observation with a scanning electron microscope and image measurement. In the observation with the scanning electron microscope, the observation magnification for observing the fine particles A adopts the same magnification as the magnification for observing the fine particles A on the substrate.

The procedure up to the calculation of the transition index is shown below.

(1) Sample preparation A thin layer of conductive paste is applied to a sample table (aluminum sample table 15 mm x 6 mm), and toner is sprayed on it. Further air blow to remove excess toner from the sample table and allow it to dry sufficiently. Set the sample table on the sample holder and adjust the sample table height to 36 mm with the sample height gauge.

(2) Setting of observation conditions for S-4800 The coverage [X2] of the fine particles A is calculated using the image obtained by observing the backscattered electron image of S-4800. Since the backscattered electron image has less charge-up than the secondary electron image, the coverage [X2] of the fine particles A can be measured with high accuracy.

Inject liquid nitrogen into the anti-contamination trap attached to the housing of S-4800 until it overflows, and leave it for 30 minutes. Start the "PC-SEM" of S-4800 and perform flushing (cleaning of the FE chip which is an electron source). Click the acceleration voltage display part of the control panel on the screen and press the [Flushing] button to open the flushing execution dialog. Confirm that the flushing intensity is 2 and execute. Confirm that the emission current due to flushing is 20 to 40 μA. Insert the sample holder into the sample chamber of the S-4800 housing. Press [Origin] on the control panel to move the sample holder to the observation position. Click the acceleration voltage display to open the HV setting dialog, and set the acceleration voltage to [0.8 kV] and the emission current to [20 μA]. In the [Basic] tab of the operation panel, set the signal selection to [SE], select [Top (U)] and [+ BSE] for the SE detector, and select [+ BSE] in the selection box to the right of [+ BSE]. L. A. 100] is selected to set the mode for observing with a backscattered electron image.

Similarly, in the [Basic] tab of the operation panel, set the probe current of the electro-optical system condition block to [Normal], the focal mode to [UHR], and the WD to [3.0 mm]. Press the [ON] button on the acceleration voltage display of the control panel to apply the acceleration voltage.

(3) Focus adjustment Drag the inside of the magnification display section of the control panel to set the magnification to 5000 (5k) times. Rotate the focus knob [COARSE] on the operation panel to adjust the aperture alignment when the entire field of view is in focus to some extent. Click [Align] on the control panel to display the alignment dialog, and select [Beam]. Rotate the STIGMA / ALIGNMENT knobs (X, Y) on the control panel to move the displayed beam to the center of the concentric circles. Next, select [Aperture] and turn the STIGMA / ALIGNMENT knobs (X, Y) one by one to stop the movement of the image or adjust it to the minimum movement. Close the aperture dialog and focus with autofocus. Repeat this operation twice more to focus.

Next, for the target toner, the magnification is set to 10000 (10k) times by dragging the inside of the magnification display section of the control panel with the midpoint of the maximum diameter aligned with the center of the measurement screen. Rotate the focus knob [COARSE] on the operation panel to adjust the aperture alignment when the focus is reached to some extent. Click [Align] on the control panel to display the alignment dialog, and select [Beam]. Rotate the STIGMA / ALIGNMENT knobs (X, Y) on the control panel to move the displayed beam to the center of the concentric circles.

Next, select [Aperture] and turn the STIGMA / ALIGNMENT knobs (X, Y) one by one to stop the movement of the image or adjust it to the minimum movement. Close the aperture dialog and focus with autofocus. After that, the magnification is set to 50,000 (50k) times, the focus is adjusted using the focus knob and the STIGMA / ALIGNMENT knob in the same manner as above, and the focus is adjusted again by autofocus. Repeat this operation again to focus. Here, if the tilt angle of the observation surface is large, the measurement accuracy of the coverage tends to be low, so by selecting the one that focuses on the entire observation surface at the same time when adjusting the focus, select the one with the least inclination of the surface. And analyze.

(4) Image saving Perform brightness adjustment in ABC mode, take a picture with a size of 640 x 480 pixels, and save it. The following analysis is performed using this image file. One photograph is taken for each toner particle, and an image is obtained for at least 100 toner particles or more.

The observed image is binarized using Image J, which is image analysis software. After binarization, only the fine particles A are extracted by setting the circle-equivalent diameter and circularity of the corresponding fine particles A from [Analyze]-[Analyze Particles], and the coverage (unit) of the fine particles A on the surface of the toner particles. : Area%) is calculated. The above measurement is performed on 100 binarized images, and the average value of the coverage (unit: area%) of the fine particles A is defined as the coverage [X2] of the fine particles A.

The migration index of the fine particles A is calculated from the area ratio [X1] of the fine particles A on the substrate and the coverage [X2] of the fine particles A using the following formula.

Transition index of fine particles A = Area ratio of fine particles A on the substrate [X1] / Coverage ratio of fine particles A [X2] × 100
<Observation of the presence or absence of a toner particle shell>
The presence or absence of a shell of toner particles can be observed by observing the morphology of the cross section of the toner particles. The specific method for observing the cross-sectional morphology of the toner particles is as follows.

First, the toner particles are sufficiently dispersed in the photocurable epoxy resin, and then the epoxy resin is cured by irradiating with ultraviolet rays to obtain a cured product. The obtained cured product is cut using a microtome equipped with a diamond blade to prepare a flaky sample having a thickness of 100 nm. After dyeing the above sample with ruthenium tetroxide as necessary, a transmission electron microscope (TEM) (trade name: electron microscope Teknai TF20XT, manufactured by FEI) was used to obtain toner under the condition of an acceleration voltage of 120 kV. Observe the cross section to obtain a TEM image.

In the above observation method, when the shell exists and the core and the shell are different components, the difference in the dyeing state and the contrast due to the element mapping are observed. The observation magnification is 20000 times.

<Detection of isosorbide-derived monomer units present on the surface of toner particles>
TOF-SIMS (TRIFT-IV, manufactured by ULVAC-PHI, Inc.) is used to detect the isosorbide-derived monomer unit present on the surface of the toner particles. The analysis conditions are as follows.

Sample preparation: Toner particles are attached to the indium sheet.

Sample pretreatment: None Primary ion: Au +
Acceleration voltage: 30kV
Charge neutralization mode: On
Measurement mode: Positive
Raster size: 100 μm
Accumulation time: 180 seconds By performing the above measurement, polyester P having an isosorbide-derived monomer unit present on the surface of the toner particles can be detected. By confirming the presence of the shell of the toner particles by observation and performing the measurement, it can be determined whether or not the shell contains polyester P.

<Measurement method of sample crystallization peak temperature>
The crystallization peak temperature of the sample is measured according to ASTM D3418-82 using a differential scanning calorimeter analyzer "Q2000 (manufactured by TA Instruments)".

The melting point of indium and zinc is used for temperature correction of the device detector, and the heat of fusion of indium is used for the correction of calorific value.

Specifically, 2 mg of a sample is precisely weighed, placed in an aluminum pan, and an empty aluminum pan is used as a reference.

The measurement temperature range is set to −10 ° C. to 200 ° C., and the measurement is performed at a heating rate of 10 ° C./min. In the measurement, the temperature is once raised from −10 ° C. to 200 ° C. at a temperature rising rate of 10 ° C./min, and then lowered from 200 ° C. to −10 ° C. at a temperature lowering rate of 10 ° C./min.

Then, the temperature is raised again from −10 ° C. to 200 ° C. at a heating rate of 10 ° C./min.

The crystallization peak temperature is obtained from the DSC curve in the temperature range of 200 ° C. to −10 ° C. at the time of the first temperature decrease.

In the DSC curve at the time of the first temperature decrease, the temperature with the highest peak height is defined as the crystallization peak temperature of the sample, with the baseline before and after the specific heat change.

<Measuring method of weight average particle diameter (D4) of toner particles>
The weight average particle diameter (D4) of the toner particles is measured as follows.

As the measuring device, a precision particle size distribution measuring device “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter) equipped with a 100 μm aperture tube by the pore electric resistance method is used. For the setting of measurement conditions and the analysis of measurement data, the attached dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter) is used. The measurement is performed with 25,000 effective measurement channels.

As the electrolytic aqueous solution used for the measurement, one in which special grade sodium chloride is dissolved in ion-exchanged water so that the concentration becomes 1% by mass, for example, "ISOTON II" (manufactured by Beckman Coulter) can be used.

Before performing measurement and analysis, set the dedicated software as follows.

On the "Change standard measurement method (SOM)" screen of the dedicated software, set the total count number in the control mode to 50,000 particles, measure once, and set the Kd value to "standard particles 10.0 μm" (Beckman Coulter). The value obtained by using (manufactured by) is set. By pressing the "threshold / noise level measurement button", the threshold and noise level are automatically set. Also, set the current to 1600 μA, the gain to 2, and the electrolyte to ISOTON II, and check "Flash of aperture tube after measurement".

On the "Pulse to particle size conversion setting" screen of the dedicated software, set the bin spacing to logarithmic particle size, the particle size bin to 256 particle size bins, and the particle size range from 2 μm to 60 μm.

The specific measurement method is as follows.

(1) Put 200 mL of the electrolytic aqueous solution in a 250 mL round bottom beaker made of glass exclusively for Multisizer 3, set it on the sample stand, and stir the stirrer rod counterclockwise at 24 rpm. Then, the dirt and air bubbles in the aperture tube are removed by the "flash of the aperture tube" function of the dedicated software.

(2) Put 30 mL of the electrolytic aqueous solution in a 100 mL flat-bottomed beaker made of glass. Among them, as a dispersant, "Contaminone N" (a 10% by mass aqueous solution of a neutral detergent for cleaning a pH 7 precision measuring instrument consisting of a nonionic surfactant, an anionic surfactant, and an organic builder, manufactured by Wako Pure Chemical Industries, Ltd. ) Is diluted 3 times by mass with ion-exchanged water, and 0.3 mL of the diluted solution is added.

(3) Two oscillators with an oscillation frequency of 50 kHz are built in with their phases shifted by 180 degrees, and an ultrasonic disperser "Ultrasonic Dispersion System Tetora 150" (manufactured by Nikkaki Bios) with an electrical output of 120 W is prepared. Put 3.3 L of ion-exchanged water in the water tank of the ultrasonic disperser, and add 2 mL of contaminationon N to this water tank.

(4) The beaker of (2) above is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid level of the electrolytic solution in the beaker is maximized.

(5) With the electrolytic aqueous solution in the beaker of (4) above being irradiated with ultrasonic waves, 10 mg of toner particles are added little by little to the electrolytic aqueous solution and dispersed. Then, the ultrasonic dispersion processing is continued for another 60 seconds. For ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted to be 10 ° C. or higher and 40 ° C. or lower.

(6) Using a pipette, the electrolytic aqueous solution of (5) above, in which toner particles are dispersed, is dropped onto the round bottom beaker of (1) above installed in the sample stand, and the measured concentration is adjusted to 5%. .. Then, the measurement is performed until the number of measured particles reaches 50,000.

(7) The measurement data is analyzed by the dedicated software attached to the device, and the weight average particle diameter (D4) is calculated. The "average diameter" of the "analysis / volume statistical value (arithmetic mean)" screen when the graph / volume% is set by the dedicated software is the weight average particle diameter (D4) of the toner particles.

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

<Production example of magnetic material (a type of black colorant)>
A 1.0 equivalent sodium hydroxide aqueous solution (containing 1% by mass of sodium hexametaphosphate in terms of P with respect to Fe) is mixed with the ferrous sulfate aqueous solution to contain ferrous hydroxide. An aqueous solution was prepared. While maintaining the pH of the aqueous solution at 9, air was blown into it and an oxidation reaction was carried out at 80 ° C. to prepare a slurry liquid for producing seed crystals.

Next, a ferrous sulfate aqueous solution was added to this slurry so that the amount was 1.0 equivalent with respect to the initial amount of alkali (sodium component of sodium hydroxide). The slurry liquid was maintained at pH 8 and the oxidation reaction was promoted while blowing air, and the pH was adjusted to 6 at the end of the oxidation reaction. Then, 1.5 parts by mass of n _- C 6H ₁₃ Si (OCH ₃ ) ₃ as a silane coupling agent was added to 100 parts by mass of iron oxide, and the mixture was sufficiently stirred, washed, filtered, and dried to be hydrophobic. Sexual iron oxide particles were obtained. After the agglomerated hydrophobic iron oxide particles were crushed, heat treatment was performed at a temperature of 70 ° C. for 5 hours to obtain a magnetic material 1. The number average particle size of the magnetic material 1 was 0.25 μm.

<Production example of polyester P1>
・ Telephthalic acid: 29.9 parts by mass ・ Bisphenol A-propylene oxide 2 mol Addendum: 48.5 parts by mass ・ Isosorbide: 1.2 parts by mass ・ Ethylene glycol: 4.5 parts by mass ・ Tetrabutoxytitanate: 0.125 The above materials were placed in an autoclave equipped with a mass decompression device, a water separator, a nitrogen gas introduction device, a temperature measuring device, and a stirring device, and the reaction was carried out under a nitrogen atmosphere at normal pressure at 200 ° C. for 5 hours.

Then, 2.1 parts by mass of trimellitic acid and 0.120 parts by mass of tetrabutoxytitanate were added and reacted at 220 ° C. for 3 hours, and further reacted under a reduced pressure of 10 to 20 mmHg for 2 hours to obtain polyester P1. rice field.

(Production example of polyester P2)
The same operation as in the production example of polyester P1 was performed except that isosorbide was removed from the production example of polyester P1, to obtain polyester P2.

<Manufacturing example of wax 1>
100.00 parts by mass of stearic acid, 48.00 parts by mass of behenyl alcohol, 0.50 parts by mass of p-toluenesulfonic acid The above materials were added under reflux, and the esterification reaction was allowed to proceed at 120 ° C. for 6 hours. During this period, the generated water was removed from the system by toluene / water azeotrope. After completion of the reaction, p-toluenesulfonic acid was neutralized with sodium hydrogen carbonate. Toluene was removed by evaporation of the resulting solution. The product was heated to 90 ° C. and then filtered through cerite to remove sodium p-toluenesulfonate to give wax 1. When the crystallization peak temperature of Wax 1 was measured by the above measuring method, it was 65 ° C.

Table 1 shows the types and physical properties of the fine particles A used in the following production examples. The number average particle size A2, the relative permittivity, and the volume resistivity in Table 1 were measured by the above measuring methods.

<Manufacturing example of toner particles 1>
・ 78.0 parts by mass of styrene ・ 22.0 parts by mass of n-butyl acrylate ・ 3.0 parts by mass of polyester P1 ・ 80.0 parts by mass of magnetic material ・ Load electric control agent T-77 (manufactured by Hodogaya Chemical Co., Ltd.) 1.0 Parts by mass / wax 1 20.0 parts by mass The above materials were uniformly dispersed and mixed using an attritor (Nippon Coke Industries, Ltd.). Then, the mixture is heated to a temperature of 60 ° C., 10.0 parts by mass of 2,2'-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator is added, and the mixture is mixed / dissolved in the mixed solution. A mixed solution containing the polymerizable monomer composition was prepared.

Further, 450 parts by mass of 0.1 mol / L Na ₃ PO ₄ aqueous solution was added to 720 parts of ion-exchanged water while stirring at 33 m / s using Clairemix (M Technique Co., Ltd.). Then, it was heated to a temperature of 60 ° C., and 67.7 parts by mass of a 1.0 mol / L CaCl ₂ aqueous solution was added to obtain an aqueous medium containing a calcium phosphate compound.

The mixed solution was put into the aqueous medium, and the mixture was stirred at 33 m / s for 15 minutes using Clairemix (M Technique Co., Ltd.) at a temperature of 60 ° C. and a nitrogen atmosphere to perform granulation. Then, the mixture was stirred with a paddle stirring blade, the temperature was raised to 70 ° C., and the polymerization reaction was carried out for 300 minutes. After completion of the polymerization reaction, the suspension was heated to 100 ° C. and kept under reduced pressure for 2 hours to remove residual monomers. Then, as a cooling step, the suspension was cooled from 95 ° C. to 45 ° C. at 120 ° C./min (cooling rate). After cooling, as an annealing step, the suspension was heated to 50 ° C. (annealing temperature) and held for 120 minutes (annealing time). After the annealing step, hydrochloric acid was added to lower the pH to 2.0 or less to dissolve and remove the calcium phosphate compound. Further, washing with water was repeated several times, dried at 40 ° C. for 72 hours using a dryer, and classified using a multi-division classifier utilizing the Coanda effect to obtain toner particles 1. Table 2 shows the physical characteristics of the toner particles 1.

<Manufacturing example of toner particles 2 to 9>
Toner particles 2 to 9 were obtained in the same manner as in the production example of toner particles 1 except that the number of copies of the wax, the type of polyester, the cooling rate, the annealing temperature, and the annealing time were changed as shown in Table 2. Table 2 shows the physical properties of the toner particles 2 to 9.

The weight average particle size D4 in Table 2 was measured by the above-mentioned measuring method, and the presence or absence of a shell was confirmed by observing by the above-mentioned observation method.

<Manufacturing example of toner 1>
The processing blades were changed from the rotating body shown in FIG. 3 to the rotating body shown in FIG. 2 in an FM mixer (trade name: FM10C, manufactured by Nippon Coke Industries Co., Ltd.), and 100.0 parts of toner particles 1 and octyltrimethoxy. 0.3 parts of sol-gel silica fine particles (number average particle size 115 nm) treated with silane were added and mixed at 2000 rpm for 15 minutes, and the first-stage external addition was performed to obtain a toner precursor 1-1.

At this time, at the same time as the start of mixing, hot water and cold water were appropriately passed through the jacket to maintain the temperature in the tank at 50 ° C.

Then, as the second-stage external addition, 100 parts of the toner precursor 1-1 and 0.2 parts of the fine particle A1 were put into the same FM mixer as the one to which the first-stage external addition was performed. Water was passed through the jacket so that the water temperature was 7 ° C., and the mixture was mixed at 2400 rpm for 5 minutes to obtain toner precursor 1-2. At this time, the flow rate of water flowing through the jacket was appropriately adjusted so that the temperature inside the FM mixer tank was 20 ° C. Then, the obtained toner precursor 1-2 was sieved with a mesh having an opening of 75 μm to obtain toner 1 (black toner). Table 4 shows the physical characteristics of the toner 1.

The rotating body shown in FIG. 3 is a rotating body that the FM10C has at the time of sale. In FIGS. 2 and 3, 140 and 150 are processing blades, 141 and 151 are the main bodies of the processing blades, and 142 and 152 are processing units. Further, in each view, (a) is a top view and (b) is a side view.

<Manufacturing example of toners 2 to 19>
In the production example of toner 1, toners 2 to 19 are obtained in the same manner except that the type of toner particles, the type and number of fine particles A, and the first-stage external addition conditions and the second-stage external addition conditions are changed as shown in Table 3. rice field. Table 4 shows the physical characteristics of the toners 2 to 19.

The physical characteristics of the toners listed in Table 4 were measured by the above-mentioned measuring method.

<Example 1>
Toner 1 was evaluated as follows. The evaluation results are shown in Table 5.

<Evaluation of low temperature fixability>
For the evaluation of low temperature fixability, a modified machine of a laser beam printer (trade name: HP LaserJet Enterprise M609dn, manufactured by HP) was used as an image forming apparatus. The modification point of the image forming apparatus was that the fixing temperature of the fuser could be set arbitrarily. The paper used for image formation was white paper (trade name: GF-C081, Canon Marketing Japan Inc., 81.4 g / m ² ).

First, the toner inside the cartridge was taken out and emptied, and then 300 g of the toner 1 was filled inside the cartridge.

In a low temperature and low humidity environment (7.5 ° C / 15% RH), the temperature of the fuser is adjusted every 5 ° C in the range of 170 ° C or higher and 230 ° C or lower using the above-mentioned modified machine and white paper, and at each temperature. Each halftone image was output. At this time, the bias was adjusted so that the image density of the halftone image at each temperature was 0.60 to 0.65. The image density was measured using a Macbeth densitometer (manufactured by Macbeth), which is a reflection densitometer, and an SPI filter.

Each of the obtained halftone images was rubbed 5 times with Sylbon paper loaded with 4.9 kPa. The lowest fixing temperature at which an image in which the reduction rate of the image density before and after rubbing was 15% or less was output was defined as the evaluation of low temperature fixing property. When the fixing temperature is 190 ° C. or lower, it is judged that the effect of the present disclosure is obtained.

<Evaluation of image density>
The evaluation of the image density was carried out using the image forming apparatus and the white paper used in the above-mentioned evaluation of the low temperature fixability. The image forming apparatus used in the evaluation was not modified.

In a high temperature and high humidity environment (30.0 ° C., 80% RH), 100 horizontal line patterns having a printing rate of 1% were output, and then the device was stopped for 10 days. Then, a solid black image of 5 mm × 5 mm was output, and the image density of the solid black image was measured. The image density was measured using a Macbeth densitometer (manufactured by Macbeth), which is a reflection densitometer, and an SPI filter. In the measurement, those having an image density of 1.35 or more were judged to have the effect of the present disclosure.

<Evaluation of pollution in non-image areas>
After the above image density measurement, a solid white image was passed through in a high temperature and high humidity environment (30.0 ° C./80% RH), and the image density (%) was measured. Further, the image density (%) of the non-passing white paper was measured, the difference (%) between these two image densities was calculated, and the value was used to evaluate the contamination of the non-image area by the toner. The image density of the measurement was measured using TC-6DS (manufactured by Tokyo Denshoku Co., Ltd.), and the average value of the measurement results of 5 points was taken as the image density. In the measurement, those having a difference in image density of less than 2.5% were judged to be good results.

<Evaluation of development streaks>
After the contamination evaluation of the non-image area described above, 100 solid white images were passed through in a high temperature and high humidity environment (30.0 ° C./80% RH), and then the toner loading amount was 0.2 mg / cm. A halftone image of ² was created. Then, the halftone image and the developing roller were visually confirmed and evaluated in that state. The evaluation criteria are shown below.

(Evaluation criteria)
A: No streaks can be seen on the developing roller or the halftone image.

B: Although the developing roller has 1 to 3 fine streaks in the circumferential direction, no streaks are seen on the halftone image.

C: The developing roller has 1 to 3 fine streaks in the circumferential direction, and 1 to 3 fine streaks can be seen on the halftone image.

D: Four or more streaks can be seen on the developing roller and the halftone image.

<Examples 2 to 14, Comparative Examples 1 to 5>
The evaluation was performed in the same manner as in Example 1. The evaluation results are shown in Table 5.

1 Fine wax domain 2 Contour line on the surface of the toner particles 3 Contour line reduced by a distance 600 nm inside from the surface of the toner particles 4 Wax domain straddling the contour line reduced by a distance 600 nm inside from the surface of the toner particles 5 Inorganic fine particles 140 Processing blade 141 Processing blade main body 142 Processing unit 150 Processing blade 151 Processing blade main body 152 Processing unit

Claims (16)

A toner containing toner particles containing a resin component and wax and inorganic fine particles on the surface of the toner particles.
In observing the cross section of the toner particles,
The domain containing the wax was observed and
When the domain having a major axis of 10 to 300 nm among the observed domains is defined as domain S and the occupied area ratio of the domain S in the region from the surface of the toner particles to 600 nm is R1, the R1 is 3.0. ~ 15.0%,
The inorganic fine particles contain fine particles A, and the inorganic fine particles contain fine particles A.
The volume resistivity of the fine particles A is 1.0 × 10 ³ to 3.0 × 10 ⁵ Ω · cm.
A toner characterized in that the relative permittivity εr of the fine particles A is 100 or more. In observing the cross section of the toner particles,
The toner according to claim 1, wherein the A1 is 30 to 150 nm, where the number average major axis A1 of all the domains in the region is used. In observing the cross section of the toner particles,
The toner according to claim 1 or 2, wherein the occupied area ratio of all the domains in the region is R2, and the R2 is 3.0 to 25.0%. In observing the cross section of the toner particles,
The toner according to any one of claims 1 to 3, wherein the number of the domains S in the region is 100 or more. The number average particle size of the fine particles A is A2.
In observing the cross section of the toner particles,
When the average major axis of the number of all the domains in the region is A1
0.3 ≦ A2 / A1 ≦ 1.2 ... (1) in which the A1 and the A2 satisfy the following formula (1).
The toner according to any one of claims 1 to 4. The migration index of the fine particles A to the polycarbonate film calculated by the following formula (2) is 3.5 to 6.5 = the migration index to the polycarbonate film = the area ratio of the fine particles A transferred to the polycarbonate film [X1] / Coverage of fine particles A on the surface of toner particles [X2] × 100 ... (2)
The toner according to any one of claims 1 to 5. The toner according to any one of claims 1 to 6, wherein the fine particles A are strontium titanate. The toner particles have a core containing the resin component and the wax, and a shell covering the surface of the core.
The toner according to any one of claims 1 to 7, wherein the shell contains a polyester P having a monomer unit represented by the following formula (3).

The toner according to any one of claims 1 to 8, wherein the fine particles A have a relative permittivity εr of 100 or more and 300 or less. The toner according to any one of claims 1 to 9, wherein the weight average particle diameter (D4) of the toner particles is 5.0 to 10.0 μm. The resin component contains a styrene acrylic resin and
The toner according to any one of claims 1 to 10, wherein the content ratio of the styrene acrylic resin in the resin component is 80.0 to 100.0% by mass. The wax is an ester wax,
The toner according to any one of claims 1 to 11, wherein the content ratio of the wax in the toner particles is 5.0 to 25.0% by mass. The toner according to any one of claims 1 to 12, wherein the number of fine particles A is 10 to 80 nm, where the average particle size is A2. The toner according to any one of claims 1 to 13, wherein the toner is a magnetic toner. A toner containing toner particles containing a resin component and wax and inorganic fine particles on the surface of the toner particles.
In observing the cross section of the toner particles,
The domain containing the wax was observed and
When the domain having a major axis of 10 to 300 nm among the observed domains is defined as domain S and the occupied area ratio of the domain S in the region from the surface of the toner particles to 600 nm is R1, the R1 is 3. It is 0 to 15.0%,
A toner characterized in that the inorganic fine particles contain strontium titanate. It ’s a toner manufacturing method.
The manufacturing method is
(I) A step of forming particles containing a polymerizable monomer and a wax in an aqueous medium.
(Ii) A step of obtaining a dispersion liquid containing a resin component obtained by polymerizing the polymerizable monomer contained in the particles and toner particles containing a wax.
(Iii) Holding step of holding the dispersion liquid at the Ta + 15 (° C.) to the Ta + 35 (° C.) when the crystallization peak temperature of the wax is Ta (° C.) (iv) The dispersion liquid is held at the Ta + 15 (° C.). ) To the cooling step of cooling from the Ta + 35 (° C.) to the Ta-35 (° C.) to the Ta-20 (° C.) at a cooling rate of 40.0 to 200.0 ° C./min.
(V) An annealing step of holding the dispersion liquid that has undergone the cooling step at the Ta-35 (° C.) to the Ta-20 (° C.) for 30 minutes or longer.
(Vi) The toner particles taken out from the dispersion liquid which has undergone the annealing step, and (vii) the toner particles taken out in the taking-out step in the Ta-35 (° C.) to the Ta-20 (° C.). In addition, it has an external addition process in which inorganic fine particles are externally added.
The inorganic fine particles contain fine particles A, and the inorganic fine particles contain fine particles A.
The volume resistivity of the fine particles A is 1.0 × 10 ³ to 3.0 × 10 ⁵ Ω · cm.
A method for producing a toner, wherein the fine particles A have a relative permittivity εr of 100 or more.

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