JP2019086764A - Toner and method for producing the toner - Google Patents

Abstract

To provide a toner which achieves low temperature fixability, heat-storage stability and temporal stability and is excellent in durability in continuous paper feeding, even when a wax excellent in plasticity of the binder resin is used.SOLUTION: A toner has toner particles containing a binder resin and wax, in which the binder resin contains a styrene acrylic copolymer, a content of the styrene acrylic copolymer in the binder resin is 50 mass% or more, the wax contains wax A, 15.0 pts.mass of the wax A is compatible to 100 pts.mass of a styrene-butylacrylate copolymer at 100°C, a domain of the wax in a cross section of the toner particles observed by a scanning transmission electron microscope exists, an average number of the domain is 20 pieces or more and 2,000 pieces or less, and when an average major axis of the domain is represented by r1 and an average minor axis thereof is represented by r2, r1 is 0.03 μm or more and 1.00 μm or less, and a ratio of r1 to r2 is 1.0 or more and 3.0 or less.SELECTED DRAWING: None

Description

  The present invention relates to a toner used to develop an electrostatic latent image formed by a method such as electrophotography, electrostatic recording, toner jet recording, etc. to form a toner image, and a method for producing the toner. .

2. Description of the Related Art In recent years, energy saving has been considered as a major technical problem in copying machines, printers, and fax machines, and a significant reduction in the amount of heat required for an image fixing apparatus is desired. Therefore, in the case of toners, there is an increasing need for so-called "low-temperature fixability" capable of fixing an image with lower energy.
As a general method for improving the low temperature fixability of the toner, a method of lowering the glass transition temperature (Tg) for the purpose of softening the binder resin to be used may be mentioned. However, simply lowering the Tg of the binder resin causes the occurrence of an offset to the fixing member due to the lack of releasability at the time of fixing, a decrease in heat resistance during storage of the toner, and the like.
As a method of softening the binder resin without lowering the Tg, it is practiced to add a plasticizer. However, in order to sufficiently soften the toner at the time of fixing, it is necessary to use a plasticizer having a large plasticizing ability to the binder resin. When such a plasticizer is used, the plasticizer is easily exuded to the toner surface during storage, and image defects due to blocking and reduced fluidity occur.
Further, in order to compensate for the releasability at the time of fixing, it is practiced to incorporate a wax having releasability into the toner. However, if it is merely contained, the wax exudes to the toner surface at the time of fixing and the offset to the fixing member occurs due to the lack of releasability at the time of fixing. Various attempts have been made to solve these problems.

For example, Patent Document 1 discloses a method of using a specific diester as a softening agent to make the thermal characteristics of the toner a specific range, and to achieve both low temperature fixability and heat resistant storage stability.
Further, in Patent Document 2, by controlling the average dispersed particle diameter of the modified layered inorganic mineral and the release agent, in the toner having a large variation in the release agent content by the particle diameter, prevention of the decrease in the fixing property and the spent Discloses a method of suppressing the occurrence of

Patent No. 6020458 Patent No. 5196120 gazette

Patent Document 1 discloses a method of reducing the toner viscosity at the time of fixing by using a softener excellent in plasticity.
However, the softener having excellent plasticity tends to migrate to the toner surface, so that the plasticizer exudes to the toner surface during storage, and the image density is reduced due to the decrease in fluidity.
On the other hand, Patent Document 2 discloses a method of uniformly finely dispersing a wax having releasability. This promotes the exudation of the wax to the toner surface at the time of fixing, and the releasability at the time of fixing is obtained.
However, since the wax does not have sufficient plasticity, the effect of softening the toner is low, and it is necessary to lower the Tg of the binder resin for low-temperature fixing. For this reason, the heat resistance at the time of storage falls.
Moreover, although the plasticizer or the mold release agent used by both methods has crystallinity, it generally crystal-grows in plate shape or needle shape. When these are present in the toner, stress is concentrated on the binder resin and the interface thereof due to a stress or the like at the time of image formation, a crack from this tends to occur, and the fluidity of the toner decreases.
In order to solve the above, by using a plasticizer having high compatibility with the binder resin, the binder resin is sufficiently softened during fixing without lowering the Tg, and the plasticizer is added during storage of the toner. It is desirable to develop a technology that does not expose the toner surface.
That is, according to the present invention, even when a wax excellent in the plasticity of the binder resin is used, the low temperature fixability, the heat resistant storage stability and the temporal stability are compatible, and the durability at the time of continuous sheet passing To provide an excellent toner. The present invention also provides a method of producing the toner.

The present invention
A toner having toner particles containing a binder resin and a wax,
The binder resin contains a styrene acrylic copolymer,
The content of the styrene acrylic copolymer in the binder resin is 50% by mass or more,
The wax contains wax A,
The wax A is compatible with 15.0 parts by mass or more at 100 ° C. with respect to 100 parts by mass of a styrene-butyl acrylate copolymer having the following composition,
In the cross section of the toner particles observed with a scanning transmission electron microscope
The wax domain is present,
The average number of the domains is 20 or more and 2000 or less,
When the average major axis of the domain is r1 and the average minor axis is r2,
The r1 is not less than 0.03 μm and not more than 1.00 μm,
The ratio of r1 to r2 is 1.0 or more and 3.0 or less,
The present invention relates to a toner characterized by
(The styrene-butyl acrylate copolymer is a copolymer of 75 parts by mass of a styrene monomer and 25 parts by mass of a butyl acrylate monomer, and has a weight average molecular weight of 30,000.)

Also, the present invention is
A toner having toner particles containing a binder resin and a wax,
The binder resin contains a styrene acrylic copolymer,
The content of the styrene acrylic copolymer in the binder resin is 50% by mass or more,
The wax contains an ester wax of a diol having 2 to 6 carbon atoms and an aliphatic monocarboxylic acid having 14 to 22 carbon atoms,
The solubility parameter of the ester wax is 8.83 (cal / cm ³ ) ^1/2 or more.
In the cross section of the toner particles observed with a scanning transmission electron microscope
The wax domain is present,
The average number of the domains is 20 or more and 2000 or less,
When the average major axis of the domain is r1 and the average minor axis is r2,
The r1 is not less than 0.03 μm and not more than 1.00 μm,
The ratio of r1 to r2 is 1.0 or more and 3.0 or less,
The present invention relates to a toner characterized by

Furthermore, the present invention
A method for producing a toner having a binder resin containing a styrene acrylic copolymer, and toner particles containing a wax,
The process for producing the toner particles includes the following process (i) or (ii):
The content of the styrene acrylic copolymer in the binder resin is 50% by mass or more,
The wax contains wax A,
The wax A is compatible with 15.0 parts by mass or more at 100 ° C. with respect to 100 parts by mass of a styrene-butyl acrylate copolymer having the following composition,
In the cross section of the toner particles observed with a scanning transmission electron microscope
The wax domain is present,
The average number of the domains is 20 or more and 2000 or less,
When the average major axis of the domain is r1 and the average minor axis is r2,
The r1 is not less than 0.03 μm and not more than 1.00 μm,
The ratio of r1 to r2 is 1.0 or more and 3.0 or less,
The present invention relates to a method for producing a toner characterized by
(I) A polymerizable monomer capable of producing a binder resin containing a styrene acrylic copolymer, and particles of a polymerizable monomer composition containing the wax are formed in an aqueous medium, and the polymerization is carried out Polymerizing the polymerizable monomer contained in the particles of the functional monomer composition.
(Ii) forming a binder resin containing a styrene acrylic copolymer in an organic solvent, and particles of a resin solution obtained by dissolving or dispersing the wax in an aqueous medium; Removing the organic solvent contained in the particles.
(The styrene-butyl acrylate copolymer is a copolymer of 75 parts by mass of a styrene monomer and 25 parts by mass of a butyl acrylate monomer, and has a weight average molecular weight of 30,000.)

  According to the present invention, even when a wax excellent in the plasticity of the binder resin is used, low-temperature fixability is compatible with heat-resistant storage stability and temporal stability, and durability during continuous sheet passing. Can provide excellent toner. Also, a method of producing the toner can be provided.

In the present invention, the descriptions of “more than or equal to or less than xxx” and “o to xxx” indicating numerical ranges mean numerical ranges including the lower limit and the upper limit which are end points unless otherwise noted.
The toner of the present invention is
A toner having toner particles containing a binder resin and a wax,
The binder resin contains a styrene acrylic copolymer,
The content of the styrene acrylic copolymer in the binder resin is 50% by mass or more,
The wax contains wax A,
The wax A is compatible with 15.0 parts by mass or more at 100 ° C. with respect to 100 parts by mass of a styrene-butyl acrylate copolymer having the following composition,
In the cross section of the toner particles observed with a scanning transmission electron microscope
The wax domain is present,
The average number of the domains is 20 or more and 2000 or less,
When the average major axis of the domain is r1 and the average minor axis is r2,
The r1 is not less than 0.03 μm and not more than 1.00 μm,
The ratio of r1 to r2 is 1.0 or more and 3.0 or less,
It is characterized by being.
(The styrene-butyl acrylate copolymer is a copolymer of 75 parts by mass of a styrene monomer and 25 parts by mass of a butyl acrylate monomer, and has a weight average molecular weight of 30,000.)

The toner contains wax A which exhibits high compatibility with a binder resin containing a styrene acrylic copolymer.
That is, at 100 ° C., the wax A is compatible with 15.0 parts by mass or more with respect to 100 parts by mass of the styrene-butyl acrylate copolymer. However, the styrene-butyl acrylate copolymer is a copolymer of 75 parts by mass of a styrene monomer and 25 parts by mass of a butyl acrylate monomer, and has a weight average molecular weight of 30,000.
The said compatible amount measured 1.00 g of this styrene- butyl acrylate copolymer to a 30 mL vial, and heated it to 100 degreeC. Thereafter, Wax A is added to the vial, mixed well at 100 ° C. and visually observed.
The compatibility is judged to be compatible if it is transparent by visual observation.
Each 0.005 g of the wax A (0.5 parts by mass with respect to 100 parts by mass of the styrene-butyl acrylate copolymer) is added, and the maximum amount judged to be compatible is determined.
When the toner particles contain the wax A having the above-mentioned properties, the low temperature fixability is improved.
In addition, with respect to the compatibility, it is preferable that Wax A be compatible with 25.0 parts by mass or more and 100 parts by mass with 100 parts by mass of a styrene-butyl acrylate copolymer at 100 ° C. It is more preferable to dissolve. On the other hand, the upper limit value of the compatibility is not particularly limited, but is preferably about 100.0 parts by mass or less.
The compatible amount can be controlled by the solubility parameter (SP value) of wax A and its molecular weight.

When the solubility parameters of the wax A and the styrene-butyl acrylate copolymer are SPw and SPc, and the weight average molecular weight of the wax A is Mw, the SPw, the SPc, and the Mw are It is preferable to satisfy the following formula (1), and it is more preferable to satisfy the following formula (1) ′. However, the unit of solubility parameter is (cal / cm ³ ) ^1/2 .
(SPc-SPw) ² × Mw ≦ 680 (1)
(SPc-SPw) ² × Mw ≦ 600 (1) ′
By using the wax A satisfying the relationship of the formula (1), the compatibility of the wax with the binder resin can be made sufficient.

On the other hand, in the cross section of the toner particle observed with a scanning transmission electron microscope,
The wax domain is present,
The average number of the domains is 20 or more and 2000 or less.
When the average number of domains is 20 or more, the speed of plasticization by the wax containing wax A with respect to the binder resin is sufficient at the time of fixing, and the toner exhibits excellent low-temperature fixability.
On the other hand, when the average number of the domains is 2000 or less, the deterioration of the heat resistant storage stability caused by the increase of the wax containing the wax A in a compatible state due to excessive fine dispersion is suppressed.
The average number of domains is preferably 50 or more and 1600 or less, and more preferably 100 or more and 1000 or less.

When the average major axis of the domain is r1 and the average minor axis is r2,
The r1 is not less than 0.03 μm and not more than 1.00 μm.
When the average major axis (r1) of the domain is 0.03 μm or more, the heat resistant storage stability deterioration due to the excessive diameter reduction of the domain is suppressed.
On the other hand, when the average major axis (r1) of the domain is 1.00 μm or less, the distance between the domain and the toner particle surface is secured to some extent, and the exposure of the wax A containing wax to the toner particle surface is suppressed. As a result, the heat-resistant storage stability of the toner is improved, and excessive exudation of the wax A at the time of durability output is suppressed, and the transfer efficiency at the time of durability output is improved.
The average major axis (r1) of the domain is preferably 0.05 μm or more and 0.95 μm or less, and more preferably 0.10 μm or more and 0.80 μm or less.

The ratio (r1 / r2) of r1 to r2 is 1.0 or more and 3.0 or less.
In the case where the value of (r1 / r2) is 3.0 or less, the domain is not plate-like, and crystals resulting from the orientation of the compatible component of the wax present in the binder resin with the passage of time The growth can suppress the wax from being exposed on the toner particle surface. As a result, even when left under severe conditions, the decrease in image density due to the decrease in fluidity is suppressed. In addition, excessive exudation of the wax A at the time of durable output is suppressed, and the transfer efficiency at the time of durable output is improved.
The value of (r1 / r2) is preferably 1.0 or more and 2.8 or less, and more preferably 1.0 or more and 2.6 or less.
As described above, low-temperature fixability is achieved by using wax A exhibiting high compatibility with a binder resin containing a styrene acrylic copolymer, and controlling the state of presence of wax domains in toner particles. It is possible to provide a toner having both heat resistant storage stability and stability over time and having excellent durability at the time of continuous sheet passing.

The method for producing the toner is not particularly limited, but in the production process of toner particles, when any of the following steps (i) or (ii) is included, it is easy to control the state of presence of wax domains in toner particles Yes.
(I) A polymerizable monomer capable of producing a binder resin containing a styrene acrylic copolymer, and particles of a polymerizable monomer composition containing the wax are formed in an aqueous medium, and the polymerization is carried out Process (suspension polymerization method) of polymerizing the polymerizable monomer contained in the particles of the functional monomer composition.
(Ii) forming a binder resin containing a styrene acrylic copolymer in an organic solvent, and particles of a resin solution obtained by dissolving or dispersing the wax in an aqueous medium; Step of removing the organic solvent contained in the particles (dissolution suspension method).

  Hereinafter, although the suspension polymerization method of said (i) is demonstrated in detail, this invention is not necessarily limited to these.

(Step of preparing polymerizable monomer composition)
Polymerizable monomer capable of producing a binder resin containing a styrene acrylic copolymer, Wax containing wax A, and other colorants, polar resins and other charge control agents as needed The components are mixed to prepare a polymerizable monomer composition.
The colorant may be dispersed in advance in a polymerizable monomer or an organic solvent with a medium stirring mill or the like, and then mixed with another composition, or may be dispersed after mixing all the compositions. .

Granulating step of particles of polymerizable monomer composition
An aqueous medium containing a dispersion stabilizer is prepared, introduced into a stirring tank or the like equipped with a stirrer having a high shear force, and the polymerizable monomer composition is added thereto and dispersed by stirring. Particles of the polymerizable monomer composition are formed in an aqueous medium.
As the dispersion stabilizer, known surfactants, organic dispersants and inorganic dispersants can be used.
Among these, the inorganic dispersants can be suitably used because they are less likely to lose stability even with polymerization temperature or time, are easy to wash, and have little influence on the toner.
Examples of the inorganic dispersant include the following.
Tricalcium phosphate, magnesium phosphate, aluminum phosphate, polyvalent metal salts of phosphate such as zinc phosphate; carbonates such as calcium carbonate, magnesium carbonate; such as calcium metaborate, calcium sulfate, barium sulfate Inorganic salts; calcium hydroxide, magnesium hydroxide, aluminum hydroxide; inorganic oxides such as silica, bentonite, alumina.
The inorganic dispersant can be almost completely removed by adding and dissolving an acid or an alkali after the completion of polymerization.

(Polymerization process)
The polymerizable monomer contained in the particles of the obtained polymerizable monomer composition is polymerized to obtain a resin particle dispersion. The binder resin is produced by polymerizing the polymerizable monomer. In the polymerization step, a general adjustable stirring vessel can be used.
The polymerization temperature is preferably 40 ° C. or more, more preferably 50 ° C. or more and 90 ° C. or less. The polymerization temperature may be constant throughout, but the temperature may be raised in the latter half of the polymerization step for the purpose of obtaining a desired molecular weight distribution. The stirring blade used for stirring may be anything as long as the resin particle dispersion can be suspended without staying and the temperature in the tank can be kept uniform.

(Step of removing volatile components)
In order to remove unreacted polymerizable monomers and the like from the resin particle dispersion in which the polymerization step is completed, a volatile component removal step may be performed. The volatile component removal step is carried out by heating and stirring the resin particle dispersion in a stirring tank provided with a stirring means. The heating conditions at the time of the volatile component removal step are appropriately adjusted in consideration of the vapor pressure of the component to be removed such as the polymerizable monomer. The volatile component removal step can be carried out under normal pressure or reduced pressure.

(Cooling process)
It is preferable to carry out a cooling step to lower the liquid temperature before sending the resin particle dispersion after completion of the volatile component removal step to the next step. Depending on the conditions of the cooling process, the state of the wax can be changed.
The cooling conditions can be determined by the cooling start temperature, the cooling rate, and the cooling end temperature.
The cooling start temperature is preferably any temperature higher than the crystallization temperature of the wax in the binder resin. When the cooling start temperature is in this range, the formation of fine crystalline nuclei of wax is generated by cooling, and the wax domains are grown from the nuclei to promote the formation of fine domains.
Further, the cooling rate is preferably 0.33 ° C./second or more, and more preferably 1.00 ° C./second or more.
When the cooling rate is in the above range, curing of the binder resin accompanying cooling is sufficiently fast, so even if it is a substance that easily produces plate-like crystals like wax A, crystal orientation growth is inhibited and it is nearly spherical. It can form a domain.
It is preferable that the cooling end temperature be equal to or lower than the glass transition temperature (Tg) of the binder resin. When the cooling completion temperature is in the above range, the growth of the wax domain can be suppressed by the curing of the binder resin.
Further, the presence state of the wax domain can be confirmed by observing the cross section of the toner particle with a scanning transmission electron microscope.

(Solid-liquid separation process, washing process and drying process)
The toner particle dispersion may be treated with acid or alkali for the purpose of removing the dispersion stabilizer attached to the toner particle surface. After removing the dispersion stabilizer from the toner particles, the toner particles are separated from the aqueous medium by a general solid-liquid separation method, but the acid or alkali and the dispersion stabilizer component dissolved in them are completely removed. Is preferably used to wash the toner particles. This washing step may be repeated several times, and after sufficient washing, solid-liquid separation may be performed again to obtain toner particles. The obtained toner particles may be dried by known drying means, if necessary.
The weight average particle diameter of the obtained toner particles is preferably 3 μm or more and 10 μm or less, and more preferably 4 μm or more and 8 μm or less. The weight average particle size of the toner particles can be controlled by the addition amount of the dispersion stabilizer used in the granulation step.

(External addition process)
An external additive may be added to the obtained toner particles for the purpose of improving the flowability, the chargeability, the caking resistance and the like. The external addition step is performed by placing the external additive and the toner particles in a mixing apparatus equipped with blades rotating at high speed and thoroughly mixing them.

On the other hand, when toner particles are obtained by the dissolution suspension method, a binder resin containing a styrene acrylic copolymer in an organic solvent, a wax A containing a wax, and, if necessary, a polar resin, a coloring agent The resin solution is prepared by uniformly dissolving or dispersing the agent and other components such as the charge control agent.
The obtained resin solution is dispersed in an aqueous medium to form particles of the resin solution, and the organic solvent contained in the obtained particles is removed to obtain toner particles having a desired particle diameter.
The obtained toner particles can be subjected to a cooling step, a washing step, a drying step and an external addition step by the same method as the above-mentioned suspension polymerization method.
The organic solvent used for the resin solution in the dissolution and suspension method is not particularly limited as long as it is compatible with the binder resin, wax and the like which becomes the raw material of toner particles, but from the viewpoint of solvent removal It is preferable that there is a certain degree of vapor pressure below the boiling point. For example, toluene, xylene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone and the like can be mentioned.

The binder resin contains a styrene acrylic copolymer.
The styrene acrylic copolymer is a copolymer of a styrene monomer and an acrylic monomer (acrylic acid or methacrylic acid and their alkyl esters).
Here, the styrene acrylic copolymer may be contained in the binder resin in a state of being composed only of the styrene acrylic copolymer, or a block copolymer with another polymer, graft, etc. It may be contained in the binder resin in the form of a copolymer or a mixture thereof.
The content of the styrene acrylic polymer in the binder resin is 50% by mass or more, and preferably 80% by mass or more and 100% by mass or less.
When the binder resin contains a styrene acrylic copolymer, the development characteristics and the durability of the toner are improved.
In addition to the styrene acrylic copolymer, a known resin or polymer used for toner can be used as the binder resin.

Examples of the styrene-based monomer include the following.
Styrene, α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, divinylbenzene and the like.
The styrene-based monomer can be used alone or in combination of two or more selected from these.

Examples of the acrylic monomer include the following.
Methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate Acrylic acid alkyl esters such as n-nonyl acrylate, n-decyl acrylate, n-dodecyl acrylate;
Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate Methacrylic acid alkyl esters such as n-nonyl methacrylate, n-decyl methacrylate, n-dodecyl methacrylate;
Acrylic acid diesters such as diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate;
Acrylic acid, methacrylic acid etc.
The acrylic monomer may be used alone or in combination of two or more selected from these.

The styrene acrylic copolymer comprises at least one copolymer selected from the group consisting of styrene-acrylic acid alkyl ester copolymer and styrene-methacrylic acid alkyl ester copolymer,
The carbon number of the alkyl group of the acrylic acid alkyl ester and the methacrylic acid alkyl ester is preferably 2 or more and 10 or less, and more preferably 2 or more and 8 or less.
When the carbon number of the alkyl group is in the above-mentioned range, the compatibility between the resulting styrene-acrylic copolymer and the wax A can be kept high. Further, the glass transition temperature (Tg) of the binder resin containing the styrene acrylic copolymer can be set to an appropriate range.
The glass transition temperature (Tg) of the binder resin can be made into a desired range by adjusting the polymerization ratio of the styrenic monomer and the acrylic monomer.
Specifically, the polymerization ratio of the styrene-based monomer and the acrylic-based monomer (styrene-based monomer: acrylic-based monomer) is 65: 35 to 100: 0 on a mass basis. Preferably, it is 70:30 to 85:15.
The glass transition temperature (Tg) of the binder resin is preferably 25 ° C. or more and 65 ° C. or less.

As a polymerization initiator used at the time of manufacture of toner particles etc., various things, such as a peroxide type polymerization initiator and an azo polymerization initiator, can be used.
Examples of organic peroxide-based polymerization initiators include peroxy esters, peroxy dicarbonates, dialkyl peroxides, peroxy ketals, ketone peroxides, hydroperoxides and diacyl peroxides.
Examples of inorganic peroxide-based polymerization initiators include persulfates and hydrogen peroxide.
Specific examples of peroxide type polymerization initiators include t-butyl peroxy acetate, t-butyl peroxy pivalate, t-butyl peroxy isobutyrate, t-hexyl peroxy acetate, and t-hexyl peroxy pi Peroxy esters such as barato, t-hexyl peroxyisobutyrate, t-butyl peroxy isopropyl monocarbonate, t-butyl peroxy 2-ethylhexyl monocarbonate, etc .;
Diacyl peroxides such as benzoyl peroxide; peroxy dicarbonates such as diisopropyl peroxy dicarbonate; peroxy ketals such as 1,1-di-t-hexylperoxycyclohexane; dialkyl peroxys such as di-t-butyl peroxide Other examples include t-butylperoxyallyl monocarbonate and the like.
Moreover, as an azo polymerization initiator, 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-) Carbonitrile), 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile, dimethyl-2,2′-azobis (2-methyl propionate), etc. Ru.
In addition, 2 or more types of these polymerization initiators can also be used simultaneously as needed.
The amount of the polymerization initiator used is preferably 0.10 parts by mass or more and 20.0 parts by mass or less with respect to 100.0 parts by mass of the polymerizable monomer.

The toner particles can also contain a polar resin.
Examples of polar resins include polyester resins.
By using a polyester resin as the polar resin, when the resin is unevenly distributed on the surface of the toner particles to form a shell, the lubricity of the resin itself can be expected.
Examples of polyester resins include condensation polymers of alcohol monomers and carboxylic acid monomers.
Examples of the alcohol monomer include the following.
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2. 0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (6) alkylene oxide adducts of bisphenol A such as 2, 2-bis (4-hydroxyphenyl) propane; ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1 , 4-butanediol, neopentyl glycol, 1,4-butenediol, 1, -Pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, hydrogenated bisphenol A, sorbitol, 1,2,3, 6-Hexanetetraol, 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.

On the other hand, examples of the carboxylic acid monomer include the following.
Aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid or anhydrides thereof; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid and azelaic acid or anhydrides thereof; alkyl group having 6 to 18 carbon atoms Or succinic acid or an anhydride thereof substituted with an alkenyl group; unsaturated dicarboxylic acids such as fumaric acid, maleic acid and citraconic acid or an anhydride thereof.
In addition, the following monomers can be used.
Polyhydric alcohols such as sorbit, sorbitan, and oxyalkylene ethers of novolak-type phenolic resins; and polyvalent carboxylic acids such as trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid and their anhydrides.

（式中、Ｒはエチレン基又はプロピレン基を示し、ｘ及びｙはそれぞれ１以上の整数であり、かつｘ＋ｙの平均値は２〜１０である。） Among them, a polycondensation product of a bisphenol derivative represented by the following formula (I) and a carboxylic acid having two or more valences is preferable because it has good charging characteristics.
Examples of the divalent or higher carboxylic acid include fumaric acid, maleic acid, phthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, acid anhydrides thereof, lower alkyl esters thereof and the like.

(Wherein R represents an ethylene group or a propylene group, x and y each represent an integer of 1 or more, and the average value of x + y is 2 to 10.)

  The content of the polar resin is preferably 1.0 part by mass or more and 20.0 parts by mass or less with respect to 100.0 parts by mass of a binder resin or a polymerizable monomer for producing the binder resin, and 2 It is more preferable that the content is not less than 0 parts by mass and not more than 10.0 parts by mass.

The toner particles may contain a colorant. Examples of the colorant include various dyes and pigments which are conventionally known.
Examples of the black colorant include carbon black, magnetic materials, and those toned to black using yellow, magenta, and cyan colorants shown below.
Examples of yellow colorants include monoazo compounds, disazo compounds, condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, allylamide compounds and the like.
Specifically, C.I. I. Pigment yellow 74, 93, 95, 109, 111, 128, 155, 174, 180, 185 and the like.
Examples of magenta colorants include monoazo compounds, condensation azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, base dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, perylene compounds, and the like.
Specifically, C.I. I. Pigment red 2, 3, 5, 6, 7, 23, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 150, 166, 169, 177, 184, 185, 202, 206, 220, 221, 238, 254, 269, C.I. I. Pigment violet 19 and the like.
Examples of cyan colorants include copper phthalocyanine compounds and derivatives thereof, anthraquinone compounds, and basic dye lake compounds.
Specifically, C.I. I. Pigment blue 1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, 66 and the like.

The toner can be used as a magnetic toner. In that case, the toner particles may contain a magnetic material. In this case, the magnetic material can also play the role of a colorant.
Examples of the magnetic substance include iron oxides such as magnetite, hematite and ferrite; metals such as iron, cobalt and nickel, or these metals and aluminum, cobalt, copper, lead, magnesium, tin, zinc, antimony and beryllium And alloys with metals such as bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium and mixtures thereof.
The colorant may be selected from the viewpoint of hue angle, saturation, lightness, light resistance, OHP transparency, and dispersibility in toner particles. The colorants may be used alone or in combination, or in the form of a solid solution.
The content of the coloring agent is preferably 1.0 part by mass or more and 20.0 parts by mass or less with respect to 100.0 parts by mass of a binder resin or a polymerizable monomer that generates the binder resin.

The wax A is compatible with 15.0 parts by mass or more at 100 ° C. with respect to 100 parts by mass of a styrene-butyl acrylate copolymer having the following composition.
The styrene-butyl acrylate copolymer is a copolymer of 75 parts by weight of a styrene monomer and 25 parts by weight of a butyl acrylate monomer, and has a weight average molecular weight of 30,000.
Moreover, it is judged that it is compatible if the compatibility is clear by visual observation.
There is no particular limitation as long as the condition is satisfied, and known waxes can be used.
From the viewpoint of compatibility with the styrene acrylic copolymer contained in the binder resin, the wax A is preferably an ester wax which is a condensation product of an alcohol component and a carboxylic acid component.
Specifically, the wax A preferably contains an ester wax of a diol and an aliphatic monocarboxylic acid.
The ester wax is preferably an ester wax of a diol having 2 to 6 carbon atoms and an aliphatic monocarboxylic acid having 14 to 22 carbon atoms.
Furthermore, the solubility parameter (SP value) of the ester wax is preferably 8.83 (cal / cm ³ ) ^1/2 or more, and 8.85 (cal / cm ³ ) ^1/2 or more. More preferable. The upper limit of the SP value is not particularly limited, but is preferably 8.90 (cal / cm ³ ) ^1/2 or less.
Examples of the diol having 2 to 6 carbon atoms include ethylene glycol, diethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol and the like. Aliphatic monoester having 14 to 22 carbon atoms Examples of carboxylic acids include aliphatic monocarboxylic acids such as myristic acid, palmitic acid, stearic acid and behenic acid.
The content of the wax A is preferably 1 to 30 parts by mass, and more preferably 5 to 25 parts by mass with respect to 100 parts by mass of the binder resin.

The wax may further contain a hydrocarbon wax.
Since the hydrocarbon wax has high phase separation property to the styrene acrylic copolymer, it precipitates earlier than the wax A in the above-mentioned cooling step, and becomes fine crystal nuclei.
Since domains of wax A are formed around this crystal nucleus, finer and more domains can be generated.
As hydrocarbon wax, aliphatic hydrocarbon wax such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, paraffin wax, Fischer-Tropsch wax; oxide of aliphatic hydrocarbon wax such as oxidized polyethylene wax or the like Block copolymers of the following: waxes obtained by grafting aliphatic hydrocarbon waxes with vinyl monomers such as styrene and acrylic acid.
The content of the hydrocarbon wax is preferably 0.5 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the binder resin.
When the content of the hydrocarbon wax is in this range, sufficient crystal nucleation effect can be obtained, and sufficient adhesion between the fixed toner image and the paper can be obtained, so that the low temperature fixing property is further improved.
The mixing mass ratio of wax A and hydrocarbon wax (wax A: hydrocarbon wax) is preferably 30: 1 to 1: 1, and more preferably 25: 1 to 2: 1.
The melting point of the wax A and the hydrocarbon wax is preferably 30 ° C. or more and 130 ° C. or less, and more preferably 60 ° C. or more and 100 ° C. or less. By exhibiting the thermal characteristics, it is easy to ensure both the low temperature fixability and the heat resistant storage stability of the obtained toner.

The toner particles may contain a charge control agent. Examples of the charge control agent include the following.
Organometallic compounds, chelate compounds, monoazo metal compounds, acetylacetone metal compounds, urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, quaternary ammonium salts, calixarenes, silicon compounds, nonmetal carboxylic acid compounds and derivatives thereof And a sulfonic acid resin having a sulfonic acid group, a sulfonic acid group, or a sulfonic acid ester group.
Specifically, the following may be mentioned as charge control agents for negative charge.
Metal compounds of aromatic carboxylic acids represented by salicylic acid, alkylsalicylic acids, dialkylsalicylic acids, naphthoic acids, dicarboxylic acids, etc .; polymers or copolymers having sulfonic acid groups, sulfonic acid groups or sulfonic acid ester groups; azo dyes Or metal salts or metal complexes of azo pigments; boron compounds, silicon compounds, calixarenes and the like.
On the other hand, examples of the charge control agent for positive charging include the following.
Quaternary ammonium salts, macromolecular type compounds having quaternary ammonium salts in side chains; guanidine compounds; nigrosine compounds; imidazole compounds and the like.
Among these, a charge control agent for negative charge is often used.
Moreover, as the polymer or copolymer having the sulfonic acid group, the sulfonic acid group or the sulfonic acid ester group, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methacrylamide-2-methylpropane Examples thereof include a homopolymer of a sulfonic acid group-containing vinyl monomer represented by sulfonic acid, vinyl sulfonic acid and methacrylic sulfonic acid, or a copolymer of the other vinyl monomer and the sulfonic acid group-containing vinyl monomer.
The content of the charge control agent is preferably 0.01 parts by mass or more and 20.0 parts by mass or less with respect to 100.0 parts by mass of the binder resin or the polymerizable monomer that forms the binder resin. More preferably, it is 0.1 parts by mass or more and 10.0 parts by mass or less.

From the viewpoint of improving the image quality, it is preferable that an external additive be added to the toner particles.
Examples of the external additive include inorganic fine particles such as silica fine particles, titanium oxide fine particles, strontium titanate fine particles, and aluminum oxide fine particles.
The inorganic fine particles are preferably hydrophobized with a hydrophobizing agent such as a silane coupling agent, silicone oil or a mixture thereof.
The content of the external additive is preferably 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100.0 parts by mass of the toner particles, and 0.1 parts by mass or more and 3.0 parts by mass or less It is more preferable that

Below, the calculation method and measurement method of each physical property value prescribed | regulated by this invention are described.
<Method of calculating solubility parameter (SP value)>
The solubility parameter (SP value) is determined using the Fedors equation (2).
The following values of Δei and Δvi are described in “Basic Science of Coatings, pp. 54-57, 1986 (槇), Table 3-9 of atoms and atomic group evaporation energy and molar volume (25 ° C. Make reference to).
The unit of the SP value is (cal / cm ³ ) ^1/2 , but 1 (cal / cm ³ ) ^1/2 = 2.046 × 10 ³ (J / m ³ ) ^1/2 according to (J / M ³ ) It can be converted to a unit of ^1/2 .
δi = (Ev / V) ^1/2 = (Δei / Δvi) ^1/2 equation (2)
Ev: evaporation energy V: molar volume Δei: evaporation energy of atom or group of component i Δvi: molar volume of atom or group of component i

<Method of Measuring Weight Average Molecular Weight (Mw) of Wax A>
The weight average molecular weight (Mw) of wax A is measured using gel permeation chromatography (GPC) as follows.
First, Wax A is dissolved in tetrahydrofuran (THF) at room temperature. Then, the obtained solution is filtered through a solvent-resistant membrane filter "Misholy Disc" (manufactured by Tosoh Corp.) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is 0.8% by mass. It measures on condition of the following using this sample solution.
Device: High-speed GPC device "HLC-8220GPC" (manufactured by Tosoh Corp.)
Column: LF-604, 2 stations [Showa Denko KK]
Eluent: THF
Flow rate: 0.6 mL / min
Oven temperature: 40 ° C
Sample injection volume: 0.020 mL
In calculating the molecular weight of the sample, standard polystyrene resin (trade name “TSK standard polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-10, A molecular weight calibration curve prepared using F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 "(manufactured by Tosoh Corporation) is used.

<Method of measuring weight average particle diameter (D4)>
The weight average particle size (D4) of the toner particles is measured as follows.
As a measuring apparatus, a precise particle size distribution measuring apparatus “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) having a 100 μm aperture tube and using a pore electrical resistance method is used. The setting of measurement conditions and the analysis of measurement data use the attached special software "Beckman Coulter Multisizer 3 Version 3.51" (manufactured by Beckman Coulter, Inc.). The measurement is performed with 25,000 channels of effective measurement channels.
As the electrolytic aqueous solution used for the measurement, a solution in which special grade sodium chloride is dissolved in ion exchange water so that the concentration is 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.
In addition, before performing measurement and analysis, set dedicated software as follows.
In the "Change Standard Measurement Method (SOM)" screen of the special software, set the total count number in the control mode to 50000 particles, set the number of measurements once, and the Kd value "standard particle 10.0 μm" (Beckman Coulter Inc. Make the obtained value. The threshold and noise level are automatically set by pressing the "Threshold / noise level measurement button". Also, set the current to 1600 μA, the gain to 2, and the electrolyte to ISOTON II, and check “Aperture tube flush after measurement”.
In the dedicated software “pulse to particle size conversion setting” screen, set the bin interval 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 Multisizer 3 and put it on the sample stand, and stir the stirrer rod counterclockwise at 24 rotations / sec. Then, dirt and air bubbles in the aperture tube are removed by the "flash of aperture tube" function of special software.
(2) Put 30 mL of electrolytic aqueous solution into a glass 100 mL flat bottom beaker. Among them, “contaminone N” (nonionic surfactant, anionic surfactant, 10% by weight aqueous solution of neutral detergent for pH 7 precision measuring instrument cleaning consisting of organic builders as a dispersing agent, Wako Pure Chemical Industries, Ltd. 3.) add 0.3 mL of a diluted solution diluted threefold with deionized water.
(3) Two oscillators with an oscillation frequency of 50 kHz are built in with 180 degrees of phase shift, and an ultrasonic dispersion device “Ultrasonic Dispersion System Tetora 150” (manufactured by Nikkaki Bios Co., Ltd.) having an electrical output of 120 W is prepared. Put 3.3 L of ion exchange water into the water tank of the ultrasonic disperser, and add 2 mL of Contaminone N into this water tank. (4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic dispersion device, and the ultrasonic dispersion device is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid surface of the electrolytic aqueous solution in the beaker is maximized.
(5) While the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, 10 mg of toner particles are added little by little to the electrolytic aqueous solution and dispersed. Then, ultrasonic dispersion processing is continued for another 60 seconds. In ultrasonic dispersion, the water temperature of the water tank is appropriately adjusted so as to be 10 ° C. or more and 40 ° C. or less.
(6) In the round bottom beaker of the above (1) placed in the sample stand, the electrolytic aqueous solution of the above (5) having toner particles dispersed using a pipette is dropped to adjust the measurement concentration to 5%. . Then, measurement is performed until the number of measurement particles reaches 50,000.
(7) The measurement data is analyzed by dedicated software attached to the device to calculate the weight average particle diameter (D4). The “average diameter” on the “analysis / volume statistical value (arithmetic mean)” screen when the graph / volume% is set by dedicated software is the weight average particle diameter (D4).

<Observation of Cross Section of Toner Particles in Scanning Transmission Electron Microscope>
The presence of wax in the toner particles is confirmed by observing the cross section of the toner particles using a scanning transmission electron microscope.
In the cross-sectional image of toner particles using a scanning transmission electron microscope, the wax is observed as a domain. By measuring the number and shape of the wax domains, the existence state of the wax is identified.
The observation procedure of the cross section of the toner particles is as follows.
The toner particles were embedded with a visible light curable embedding resin (D-800, manufactured by Nisshin EM Co., Ltd.), and cut to a thickness of 70 nm by an ultrasonic ultramicrotome (UC7, manufactured by Leica Co., Ltd.).
Among the obtained flake samples, those having a toner particle cross-sectional diameter within 10% of the weight average particle diameter (D4) ± 2.0 μm of the toner particles are arbitrarily selected.
The selected thin film sample is stained for 15 minutes in a 500 Pa atmosphere of RuO ₄ gas using a vacuum staining apparatus (VSC4R1H, manufactured by Filgen), and the scanning image mode of a scanning transmission electron microscope (JEM 2800, JEOL) is used. Create a STEM image.
An image was acquired with a probe size of STEM of 1 nm and an image size of 1024 × 1024 pixels. In addition, the contrast of the bright-field image Detector Control panel is adjusted to 1425, the brightness is adjusted to 3750, the contrast of the image control panel is adjusted to 0.0, the brightness is adjusted to 0.5, and the Gammma is adjusted to 1.00 to obtain a STEM image.
The obtained STEM image is binarized (step 120/255 steps) with image processing software "Image-Pro Plus (made by Media Cybernetics)" to clearly distinguish the domain of the wax domain and the binder resin. Turn
The part that looks white when the threshold of binarization is 210 is the wax domain.

<Method for calculating average number of wax domains, average major axis, and average minor axis>
In STEM images of 10 selected toner particle cross sections, the number of domains of each wax is counted, and the average value thereof is taken as the average number of domains.
In addition, in the STEM image of the selected 10 toner particle cross sections, each 2 μm × 2 μm area is arbitrarily selected, the maximum diameter of all the domains contained therein is measured, and the average value is the average major diameter of the domains It is assumed that (r1). Similarly, all the minimum diameters of the domains are measured, and the average value thereof is taken as the average minor diameter (r2) of the domains.

  EXAMPLES Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples. All parts used in the examples indicate parts by mass.

<Production Example of Toner Particles 1>
Styrene 75.0 parts n-butyl acrylate 25.0 parts 1,6-hexanediol diacrylate 0.6 parts Copper phthalocyanine pigment (Pigment Blue 15: 3) 6.0 parts salicylic acid aluminum compound 0.7 Part (Bontron E-88: made by Orient Chemical Company)
· Polar resin 4.0 parts (Saturated polyester resin obtained by condensation polymerization reaction of 2 moles of propylene oxide of bisphenol A with terephthalic acid and isophthalic acid; weight average molecular weight is 13,000
, Acid value 8 mg KOH / g, glass transition temperature 74 ° C)
Wax 1 (ethylene glycol distearate: melting point 76 ° C.) 15.0 parts Wax 2 (Fisher-Tropsch wax: melting point 77 ° C.) 1.0 part And dispersed for 2 hours using a wet attritor (manufactured by Nippon Coke Kogyo Co., Ltd.) to obtain a polymerizable monomer composition 1.
On the other hand, 6.3 parts of sodium phosphate (Na ₃ PO ₄ ) was added to 414.0 parts of ion-exchanged water, and the mixture was heated to 60 ° C. while being stirred using Creamix (manufactured by Em Technique Co., Ltd.).
Thereafter, an aqueous solution of calcium chloride in which 3.6 parts of calcium chloride (CaCl ₂ ) is dissolved in 25.5 parts of ion exchanged water is added, and stirring is further continued, and tricalcium phosphate (Ca ₃ (PO ₄ ) ₂ An aqueous medium containing a dispersion stabilizer consisting of
9.0 parts of t-butyl peroxypivalate which is a polymerization initiator is added to the polymerizable monomer composition 1, and this is put into the above aqueous medium, and maintained at 15,000 rpm with the above-mentioned Creamix. The granulation process was carried out for 10 minutes.
Thereafter, polymerization is carried out for 5 hours while maintaining the temperature at 70 ° C. while stirring in a stirring tank equipped with a general stirrer, then the temperature is raised to 85 ° C., held for 1 hour, and further raised to 100 ° C. Hold for 2 hours.
Thereafter, the toner particle dispersion liquid 1 was obtained by cooling to 40 ° C. at a rate of 1.00 ° C./sec.
Hydrochloric acid is added to the toner particle dispersion 1, the dispersion stabilizer is dissolved with a pH of 1.4 or less, and filtration, washing and drying are performed to obtain toner particles 1.

<Production Example of Toner Particles 2 to 19 and 21>
Toner particles 2 to 19 and 21 were obtained in the same manner as in the production example of toner particle 1 except that the materials used and the cooling conditions were changed as shown in Table 1.

表中、
ワックス１における表記（Ｘ）は、「ワックス１の１００℃における、スチレン−アクリル酸ブチル共重合体１００質量部に対して相溶する質量部」を表し、ＳＰ値の単位は、（ｃａｌ／ｃｍ^３）^１／２である。
ワックス２における表記（Ａ）は、フィッシャートロプシュワックス（融点７７℃）を意味する。

In the table,
The notation (X) in wax 1 represents "part by mass compatible with 100 parts by mass of styrene-butyl acrylate copolymer at 100 ° C of wax 1", and the unit of the SP value is (cal / cm ³ ) ^1/2 .
The designation (A) for Wax 2 means Fischer-Tropsch wax (melting point 77 ° C.).

<Production Example of Toner Particles 20>
The following materials were placed under a nitrogen atmosphere in a reaction vessel equipped with a reflux condenser, a stirrer, and a nitrogen introduction pipe.
-100.0 parts of toluene-75.0 parts of styrene-25.0 parts of n-butyl acrylate-0.6 parts of 1,6-hexanediol diacrylate-3.0 parts of t-butyl peroxypivalate The mixture was stirred at 200 rotations per minute, heated to 70 ° C., and stirred for 10 hours to obtain a binder resin solution 20. Then
· Binder resin solution 20 160.0 parts · Polar resin 3.2 parts (Saturated polyester resin obtained by condensation polymerization reaction of 2 moles of propylene oxide of bisphenol A with terephthalic acid and isophthalic acid; weight average; Molecular weight 13,000, acid value 8 mg KOH / g, glass transition temperature 74 ° C)
Wax 1 (ethylene glycol distearate: melting point 76 ° C.) 12.0 parts Wax 2 (Fisher Tropsch wax: melting point 77 ° C.) 0.8 parts Copper phthalocyanine pigment (Pigment Blue 15: 3) 4.8 parts 0.6 parts of aluminum salicylate compound (Bontron E-88: manufactured by Orient Chemical Co., Ltd.)
The above components were mixed and dispersed for 10 hours using a wet attritor (manufactured by Nippon Coke Kogyo Co., Ltd.) containing ceramic beads having a diameter of 15 mm, to obtain a resin composition solution 20.
On the other hand, 6.3 parts of sodium phosphate (Na ₃ PO ₄ ) was added to 414.0 parts of ion-exchanged water, and the mixture was heated to 60 ° C. while being stirred using Creamix (manufactured by Em Technique Co., Ltd.).
Thereafter, an aqueous solution of calcium chloride in which 3.6 parts of calcium chloride (CaCl ₂ ) is dissolved in 25.5 parts of ion exchanged water is added, and stirring is further continued, and tricalcium phosphate (Ca ₃ (PO ₄ ) ₂ An aqueous medium containing a dispersion stabilizer consisting of
The resin composition solution 20 was charged into the aqueous medium, and a granulation process was carried out for 10 minutes while maintaining the speed of 15000 rpm in the above-mentioned Clearmix, to obtain a resin composition dispersion 20.
The temperature in the resin composition dispersion liquid 20 was raised to 95 ° C. and stirring was carried out for 120 minutes to remove toluene in the resin composition dispersion liquid 20.
Thereafter, the toner particle dispersion liquid 20 was obtained by cooling to 40 ° C. at a rate of 1.00 ° C./sec.
Hydrochloric acid was added to the toner particle dispersion 20 to dissolve the dispersion stabilizer with a pH of 1.4 or less, and filtered, washed, and dried to obtain toner particles 20.

(Examples 1 to 15 and Comparative Examples 1 to 6)
To 100.0 parts of the obtained toner particles, 1.0 part of silica fine particles having a number average particle diameter of 40 nm of primary particles is added and mixed using an FM mixer (manufactured by Nippon Coke Kogyo Co., Ltd.). 20 to 21 (toners of Examples 1 to 13 and 14 to 15) were obtained. Further, Toners 14 to 19 (toners of Comparative Examples 1 to 6) were obtained in exactly the same manner. Physical properties of the obtained toner are shown in Table 2.

表中にワックスのドメインにおける、
「ｒ１」は平均長径を、「ｒ２」は平均短径を表し、
トナー粒子における、「Ｄ４」は重量平均粒径を表す。

In the wax domain in the table,
"R1" represents the average major axis, and "r2" represents the average minor axis,
In the toner particles, "D4" represents a weight average particle size.

The performance of each of the obtained toners was evaluated according to the following method.
[Evaluation 1: Image density after severe standing]
200 g of the toner was left under an environment of 40 ° C./95% relative humidity for 30 days, and this was used as a toner for evaluation.
Image evaluation was performed under normal temperature and normal humidity environment (temperature 23 ° C., relative humidity 50%) using LBP-7700C (manufactured by Canon Inc.) as an image forming apparatus. The image density was measured as an index of the coloring power of the toner.
The loading amount of the toner was adjusted to 0.30 mg / cm ² on A4 color laser copier paper (Canon 80 g / m ² ), and a solid image was output.
Then, the density of the solid image was evaluated by measuring (upper right, lower right, center, upper left, lower left five point average). The image density was measured relative to a white background portion having an image density of 0.00 using a "504 spectrodensitometer" (manufactured by X-Rite).
(Evaluation criteria)
A: Image density is 1.45 or more B: Image density is 1.35 to 1.45 C: Image density is 1.20 to 1.35 D: Image density is 1.05 to 1.20 E: Image density is less than 1.05

[Evaluation 2: Transfer efficiency after endurance output]
The transfer efficiency is an index of transferability showing how much% of the toner developed on the photosensitive drum is transferred onto the intermediate transfer belt.
The transfer efficiency was measured by the following procedure.
First, toner was filled in a process cartridge of a full-color printer "LBP-5050" (manufactured by Canon Inc.), and a solid image was continuously output on a recording medium.
After 3000 sheets of the solid image are output, the image forming process is performed until the toner is transferred to the intermediate transfer belt, and the toner transferred onto the intermediate transfer belt and the toner remaining on the photosensitive drum after transfer are transparent Was peeled off with a polyester adhesive tape.
The difference in density obtained by subtracting the toner density of the one obtained by sticking only the adhesive tape on the paper was calculated from the toner density of the one obtained by sticking the peeled adhesive tape on the paper.
The transfer efficiency is the ratio of the toner density difference on the intermediate transfer belt when the sum of the respective toner density differences is 100. The higher the ratio, the better the transfer efficiency.
The measurement environment was performed under high temperature and high humidity environment (30 ° C./relative humidity 80%), and the evaluation of the transfer efficiency after outputting 3000 sheets of the image was judged based on the following criteria.
The toner concentration was measured with a "504 spectrodensitometer" (manufactured by X-Rite).
(Evaluation criteria)
A: Transfer efficiency is 98% or more B: Transfer efficiency is 95% or more and less than 98% C: Transfer efficiency is 92% or more and less than 95% D: Transfer efficiency is 89% or more and less than 92% E: Transfer efficiency is less than 89%

[Evaluation 3: Low temperature fixability]
Color laser printer (HP Color LaserJet) with fixing unit removed
3525 dn (manufactured by HP) were prepared, and the toner was removed from the cyan cartridge and filled with the toner to be evaluated instead.
Next, using a toner filled on an image receiving paper (HP Laser Jet 90, manufactured by HP, 90 g / m ² ), a 2.0 cm long and 15.0 cm unfixed toner image (toning amount: 0. 5). 9 mg / cm ² ) was formed in a portion 1.0 cm from the upper end with respect to the sheet passing direction.
Next, the removed fixing unit was modified so that the fixing temperature and process speed could be adjusted, and a fixing test of the unfixed image was performed using this.
First, under normal temperature and humidity environment (23 ° C / relative humidity 60%), the process speed is set to 250 mm / s, the initial temperature is 110 ° C. and the preset temperature is sequentially raised by 5 ° C. We fixed the incoming image.
The evaluation criteria for low temperature fixability are as follows.
The low temperature side fixing start point is the lower limit temperature at which the low temperature offset phenomenon (the phenomenon that a part of the toner adheres to the fixing device) is not observed.
(Evaluation criteria)
A: Low temperature side fixing starting point is 130 ° C. or less B: Low temperature side fixing starting point is 135 ° C. to 145 ° C. C: Low temperature side fixing starting point is 150 ° C. to 160 ° C. D: Low temperature side fixing starting point is 165 ° C. or more 175 ° C. or less E: Low temperature side fixing start point is 180 ° C. or more

[Evaluation 4: Heat-resistant storage stability]
Take 5 g of each toner into a 50 mL polyester cup, and measure the temperature at 55 ° C / 10% relative humidity
It was left to stand for 3 days, and the presence or absence of aggregates was examined and evaluated according to the following criteria.
(Evaluation criteria)
A: No clumps are generated B: Slight clumps are generated, C is loosened by light shaking C: Slight clumps are generated, Crushed when lightly pressed with a finger D: Clumps are generated, lightly crushed with a finger does not crush E: completely aggregated

  The results of toner performance evaluation are shown in Table 3.

Claims (13)

A toner having toner particles containing a binder resin and a wax,
The binder resin contains a styrene acrylic copolymer,
The content of the styrene acrylic copolymer in the binder resin is 50% by mass or more,
The wax contains wax A,
The wax A is compatible with 15.0 parts by mass or more at 100 ° C. with respect to 100 parts by mass of a styrene-butyl acrylate copolymer having the following composition,
In the cross section of the toner particles observed with a scanning transmission electron microscope
The wax domain is present,
The average number of the domains is 20 or more and 2000 or less,
When the average major axis of the domain is r1 and the average minor axis is r2,
The r1 is not less than 0.03 μm and not more than 1.00 μm,
The ratio of r1 to r2 is 1.0 or more and 3.0 or less,
Toner characterized by being.
(The styrene-butyl acrylate copolymer is a copolymer of 75 parts by mass of a styrene monomer and 25 parts by mass of a butyl acrylate monomer, and has a weight average molecular weight of 30,000.) When the solubility parameters of the wax A and the styrene-butyl acrylate copolymer are SPw and SPc, and the weight average molecular weight of the wax A is Mw,
The SPw, the SPc, and the Mw satisfy a relationship represented by the following formula (1) (where, the unit of solubility parameter is (cal ^/ cm ^{3) 1/2.),} Toner according to claim 1.
(SPc-SPw) ² × Mw ≦ 680 (1) The styrene acrylic copolymer is
A styrene-acrylic acid alkyl ester copolymer, and at least one copolymer selected from the group consisting of a styrene-methacrylic acid alkyl ester copolymer,
The toner according to claim 1, wherein the alkyl alkyl ester of the acrylic acid alkyl ester and the alkyl ester of the methacrylic acid alkyl ester has 2 to 10 carbon atoms.   The toner according to any one of claims 1 to 3, wherein the wax A contains an ester wax of a diol and an aliphatic monocarboxylic acid. The wax A contains an ester wax of a diol having 2 to 6 carbon atoms and an aliphatic monocarboxylic acid having 14 to 22 carbon atoms,
Solubility parameter of the ester wax is 8.83 ^(cal / ^{cm 3) 1/2} or more, the toner according to any one of claims 1 to 3.   The toner according to any one of claims 1 to 5, wherein the wax further contains a hydrocarbon wax. A toner having toner particles containing a binder resin and a wax,
The binder resin contains a styrene acrylic copolymer,
The content of the styrene acrylic copolymer in the binder resin is 50% by mass or more,
The wax contains an ester wax of a diol having 2 to 6 carbon atoms and an aliphatic monocarboxylic acid having 14 to 22 carbon atoms,
The solubility parameter of the ester wax is 8.83 (cal / cm ³ ) ^1/2 or more.
In the cross section of the toner particles observed with a scanning transmission electron microscope
The wax domain is present,
The average number of the domains is 20 or more and 2000 or less,
When the average major axis of the domain is r1 and the average minor axis is r2,
The r1 is not less than 0.03 μm and not more than 1.00 μm,
The ratio of r1 to r2 is 1.0 or more and 3.0 or less,
Toner characterized by being. A method for producing a toner having a binder resin containing a styrene acrylic copolymer, and toner particles containing a wax,
The process for producing the toner particles includes the following process (i) or (ii):
The content of the styrene acrylic copolymer in the binder resin is 50% by mass or more,
The wax contains wax A,
The wax A is compatible with 15.0 parts by mass or more at 100 ° C. with respect to 100 parts by mass of a styrene-butyl acrylate copolymer having the following composition,
In the cross section of the toner particles observed with a scanning transmission electron microscope
The wax domain is present,
The average number of the domains is 20 or more and 2000 or less,
When the average major axis of the domain is r1 and the average minor axis is r2,
The r1 is not less than 0.03 μm and not more than 1.00 μm,
The ratio of r1 to r2 is 1.0 or more and 3.0 or less,
A method of producing a toner, characterized in that
(I) A polymerizable monomer capable of producing a binder resin containing a styrene acrylic copolymer, and particles of a polymerizable monomer composition containing the wax are formed in an aqueous medium, and the polymerization is carried out Polymerizing the polymerizable monomer contained in the particles of the functional monomer composition.
(Ii) forming a binder resin containing a styrene acrylic copolymer in an organic solvent, and particles of a resin solution obtained by dissolving or dispersing the wax in an aqueous medium; Removing the organic solvent contained in the particles.
(The styrene-butyl acrylate copolymer is a copolymer of 75 parts by mass of a styrene monomer and 25 parts by mass of a butyl acrylate monomer, and has a weight average molecular weight of 30,000.) When the solubility parameters of the wax A and the styrene-butyl acrylate copolymer are SPw and SPc, and the weight average molecular weight of the wax A is Mw,
The toner according to claim 8, wherein the SPw, the SPc, and the Mw satisfy the relationship of the following formula (1) (provided that the unit of solubility parameter is (cal / cm ³ ) ^1/2 ): Method.
(SPc-SPw) ² × Mw ≦ 680 (1) The styrene acrylic copolymer is
A styrene-acrylic acid alkyl ester copolymer, and at least one copolymer selected from the group consisting of a styrene-methacrylic acid alkyl ester copolymer,
10. The method for producing a toner according to claim 8, wherein the number of carbon atoms of the alkyl group of the acrylic acid alkyl ester and the methacrylic acid alkyl ester is 2 or more and 10 or less.   The method for producing a toner according to any one of claims 8 to 10, wherein the wax A contains an ester wax of a diol and an aliphatic monocarboxylic acid. The wax A contains an ester wax of a diol having 2 to 6 carbon atoms and an aliphatic monocarboxylic acid having 14 to 22 carbon atoms,
Solubility parameter of the ester wax, 8.83 is ^(cal / ^{cm 3) 1/2} or more, the production method of the toner according to any one of claims 8-10.   The method for producing a toner according to any one of claims 8 to 12, wherein the wax further contains a hydrocarbon wax.