JP6930188B2 - Core-shell toner for static charge image development - Google Patents

Description

The present invention relates to a core-shell type toner for developing an electrostatic charge image.

In recent years, there has been a demand for higher speed / energy saving of copying machines, and development of toner for static charge image development having excellent low temperature fixability is being promoted. In such a toner for static charge image development, it is necessary to lower the melting temperature and melting viscosity of the binder resin, and the low temperature fixability is improved by adding a crystalline resin such as a crystalline polyester resin. Toners for developing electrostatic charge images have been developed.

As the toner for static charge image development with improved low-temperature fixability, for example, in Patent Document 1, an addition polymer resin (A) and a composite resin (B) containing a structural unit whose core particles are derived from styrene are used. A core-shell type electrostatic charge image containing one or more selected from an amorphous polyester resin (C), an addition polymer resin (D) containing a structural unit derived from styrene, and a composite resin (E). Development toners have been proposed.

Japanese Unexamined Patent Publication No. 2015-049320

However, the technique described in Patent Document 1 has a problem that the heat-resistant storage property is deteriorated because the phase separation between the core particles and the shell layer is insufficient. Further, the compatibility between the addition polymerization resin contained in the core particles and the composite resin is also insufficient, and there is also a problem that the core particles melt slowly especially at the time of high-speed fixing, and sufficient low-temperature fixability cannot be exhibited.

Therefore, an object of the present invention is to provide a toner for static charge image development which has excellent low-temperature fixability at the time of high-speed fixing and is also excellent in heat-resistant storage property.

The present inventors have conducted diligent research in order to solve the above problems. As a result, a core portion containing a vinyl resin having a structural unit derived from styrene and a crystalline polyester resin using a specific monomer component, and a shell portion containing an amorphous polyester resin using a specific monomer component. It has been found that the above-mentioned problems can be solved by a core-shell type static charge image developing toner having the above, and the present invention has been completed.

That is, the present invention is a core-shell type toner for static charge image development containing at least a binder resin and a mold release agent, and the binder resin is a vinyl resin (a) having a structural unit derived from styrene, a polyvalent carboxylic. A crystalline polyester resin (b) containing an acid component and a polyvalent alcohol component composed of an aliphatic diol having 2 to 5 carbon atoms, and a polyvalent carboxylic acid component, a bisphenol A propylene oxide adduct, and a bisphenol A ethylene oxide adduct. It contains an amorphous polyester resin (c) containing a polyhydric alcohol component, and has the vinyl resin (a) and the crystalline polyester resin (b) in the core portion of the toner, and the shell of the toner. This is a core-shell type toner for developing an electrostatic charge image, which has the amorphous polyester resin (c) in a portion.

According to the present invention, there is provided a toner for static charge image development which has excellent low-temperature fixability at the time of high-speed fixing and is also excellent in heat-resistant storage property.

The present invention is a core-shell type toner for static charge image development containing at least a binder resin and a mold release agent, wherein the binder resin is a vinyl resin (a) having a styrene-derived structural unit and a polyvalent carboxylic acid component. a structural unit derived from a structural unit derived from the crystalline polyester resin (b), and polycarboxylic acid component containing a constituent unit derived from a polyhydric alcohol component consisting of aliphatic diols having 2 to 5 carbon atoms, a The amorphous polyester resin (c) containing the bisphenol A propylene oxide adduct and the structural unit derived from the polyhydric alcohol component containing the bisphenol A ethylene oxide adduct, and the core portion of the toner. It is a core-shell type toner for static charge image development, which has a vinyl resin (a) and the crystalline polyester resin (b), and has the amorphous polyester resin (c) in the shell portion of the toner. The core-shell type toner for static charge image development of the present invention having such a configuration has excellent low-temperature fixability at the time of high-speed fixing and is also excellent in heat-resistant storage property.

The reason why the above effect can be obtained by the core-shell type toner for developing an electrostatic charge image of the present invention is unknown, but the following mechanism can be considered.

By using an aliphatic diol having a short chain length of 2 to 5 carbon atoms as the alcohol component of the crystalline polyester resin (b) contained in the core portion (core particles), a vinyl resin (a) having a structural unit derived from styrene is used. ) Is enhanced, and the dispersibility of the crystalline polyester resin is enhanced in the core portion. As a result, the crystalline polyester resin (b) melts quickly, and excellent low-temperature fixability can be exhibited at the time of high-speed fixing.

In addition, the shell portion (shell layer) that covers the surface of the core portion contains an amorphous polyester resin (c) containing a bisphenol A propylene oxide adduct and a bisphenol A ethylene oxide adduct as polyhydric alcohol components. As a result, the compatibility between the core portion and the shell portion is appropriately suppressed, so that the heat-resistant storage property of the toner can be improved, and the flexibility of the shell portion is also increased, which is excellent at the time of high-speed fixing. Demonstrates low-temperature fixability.

The above mechanism is speculative, and the present invention is not limited to the above mechanism.

Hereinafter, embodiments of the present invention will be described. The present invention is not limited to the following embodiments. Unless otherwise specified, the operation and physical properties are measured under the conditions of room temperature (20 to 25 ° C.) / relative humidity of 40 to 50% RH. In the present specification, the core-shell type toner for developing an electrostatic charge image of the present invention is also simply referred to as "toner of the present invention" or "toner".

Further, particles containing a binder resin and a mold release agent and not containing an external additive are also referred to as "toner matrix particles", and particles in which an external additive is added to the toner matrix particles are also referred to as "toner particles".

The core-shell structure of the toner of the present invention is not limited to a structure in which the shell portion completely covers the core portion. For example, the shell portion does not completely cover the core portion, and the core portion is sometimes formed. It may be an exposed structure.

The core-shell structure can be confirmed by observing the cross-sectional structure of the toner using, for example, a known means such as a transmission electron microscope (TEM) or a scanning probe microscope (SPM).

[Bundling resin]
The binder resin according to the present invention is a crystalline polyester containing a vinyl resin (a) having a structural unit derived from styrene, a polyvalent carboxylic acid component, and a polyhydric alcohol component containing an aliphatic diol having 2 to 5 carbon atoms. Includes the resin (b) and an amorphous polyester resin (c) containing a polyvalent carboxylic acid component and a polyhydric alcohol component containing a bisphenol A propylene oxide adduct and a bisphenol A ethylene oxide adduct. Then, the vinyl resin (a) and the crystalline polyester resin (b) are contained in the core portion of the toner, and the amorphous polyester resin (c) is contained in the shell portion of the toner.

[Vinyl resin (a)]
The toner of the present invention contains a vinyl resin (a) having a styrene-derived structural unit in the core portion. Since the vinyl resin (a) has a structural unit derived from styrene, the compatibility with the crystalline polyester resin (b) contained in the same core portion can be easily controlled.

The type of the vinyl resin (a) is not particularly limited, but the manufacturability in the emulsification and agglomeration method (that is, by producing a latex having a uniform agglomerate property, a toner having a desired particle size distribution can be obtained) and heat fixing. Considering the balance between plasticity at the time and compatibility with the crystalline polyester resin (b), a styrene acrylic resin is preferable. Hereinafter, the styrene acrylic resin will be described.

<Styrene acrylic resin (styrene acrylic copolymer)>
In the present specification, the styrene-acrylic resin refers to a resin having at least a structural unit derived from styrene and a structural unit derived from a (meth) acrylic acid ester monomer. The styrene acrylic resin can be obtained by polymerizing at least styrene and a (meth) acrylic acid ester monomer.

The styrene acrylic resin may contain a structural unit derived from a styrene derivative having a known side chain or functional group in the styrene structure, in addition to the structural unit derived from styrene.

Examples of such styrene derivatives include o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, and pt. Examples thereof include -butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene and pn-dodecyl styrene. The styrene derivative may be used alone or in combination of two or more.

Specific examples of the (meth) acrylic acid ester monomer include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, n-pentyl acrylate, and n. Acrylate esters such as −hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate, n-behenyl acrylate, n-tricosanyl acrylate, phenylacrylate phenyl; methyl methacrylate, ethyl methacrylate, n- Propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, n-pentyl methacrylate, n-hexyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, lauryl methacrylate, n-behenyl methacrylate, Examples thereof include methacrylic acid esters such as n-tricosanyl methacrylate, phenyl methacrylate, diethylaminoethyl methacrylate and dimethylaminoethyl methacrylate.

These (meth) acrylic acid ester monomers may be used alone or in combination of two or more.

Among these, it is preferable to use the (meth) acrylic acid alkyl ester represented by the following general formula (1). That is, it is preferable that the vinyl resin (a) further has a structural unit derived from the (meth) acrylic acid alkyl ester represented by the following general formula (1).

In the above general formula (1), R ¹ is a hydrogen atom or a methyl group, and R ² is an alkyl group having 6 to 22 carbon atoms. The alkyl group of R ² may be linear or branched.

By having a structural unit derived from the (meth) acrylic acid alkyl ester represented by the general formula (1), the vinyl resin (a) can be present between the molecular chains of the crystalline polyester resin (b). Become. As a result, the fine dispersion of the crystalline polyester resin (b) is further promoted, and the low-temperature fixability at the time of high-speed fixing can be further improved.

Examples of the (meth) acrylic acid alkyl ester represented by the general formula (1) are n-hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate, n-behenyl acrylate, and n-. Examples thereof include tricosanyl acrylate, n-hexyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, lauryl methacrylate, n-behenyl methacrylate, n-tricosanyl methacrylate and the like.

The styrene acrylic resin may have a general vinyl monomer-derived structural unit in addition to the styrene-derived structural unit and the (meth) acrylic acid ester monomer-derived structural unit described above. The vinyl monomers that can be used are illustrated below, but the vinyl monomers are not limited thereto.

(1) Olefins Ethylene, propylene, isobutylene, etc. (2) Vinyl esters Vinyl propionate, vinyl acetate, vinyl benzoate, etc. (3) Vinyl ethers Vinyl methyl ether, vinyl ethyl ether, etc. (4) Vinyl ketones Vinyl methyl ketone, etc. Vinyl ethyl ketone, vinyl hexyl ketone, etc. (5) N-vinyl compounds N-vinylcarbazole, N-vinylindole, N-vinylpyrrolidone, etc. (6) Other vinyl compounds such as vinylnaphthalene and vinylpyridine, acrylonitrile, methacrylonitrile Acrylic acid such as nitrile and acrylamide, or methacrylic acid derivative and the like.

Further, a vinyl monomer having a carboxyl group can also be used. Specific examples of this include vinyl monomers having a carboxyl group such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, silicic acid, fumaric acid, maleic acid monoalkyl ester, and itaconic acid monoalkyl ester. Be done. Of these, acrylic acid or methacrylic acid is preferable.

Further, it is also possible to prepare a resin having a crosslinked structure by using a polyfunctional vinyl monomer.

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

The method for producing the styrene acrylic resin is not particularly limited, and known such as a massive polymerization method, a solution polymerization method, an emulsion polymerization method, a miniemulsion method, and a dispersion polymerization method using a known oil-soluble or water-soluble polymerization initiator. A method of polymerizing by the polymerization method of the above can be mentioned. If necessary, a known chain transfer agent such as n-octyl mercaptan may be used.

The content of the styrene-derived structural unit in the styrene acrylic resin used in the present invention is not particularly limited, but is preferably 40 to 95% by mass, more preferably 50 to 80% by mass, based on the entire monomer. The content of the structural unit derived from the (meth) acrylic acid ester monomer is preferably 5 to 60% by mass, more preferably 20 to 50% by mass, based on the entire monomer.

The molecular weight of the styrene acrylic resin is preferably 2,000 to 1,000,000 in terms of weight average molecular weight (Mw). The number average molecular weight (Mn) is preferably 1,000 to 100,000. By setting the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the styrene acrylic resin within the above ranges, it is effective to suppress the occurrence of the offset phenomenon.

The number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw / Mn) of each resin contained in the binder resin are measured by the following gel permeation chromatography (GPC) method. Can be measured by.

That is, using the apparatus "HLC-8220" (manufactured by Tosoh Corporation) and the column "TSKguardcolum + TSKgelSuperHZM-M3 series" (manufactured by Tosoh Corporation), while maintaining the column temperature at 40 ° C., tetrahydrofuran (THF) was used as the carrier solvent at a flow velocity. Flow at 0.2 mL / min. The measurement sample is dissolved in tetrahydrofuran so as to have a concentration of 1 mg / mL under the dissolution conditions of treating at room temperature (25 ° C.) for 5 minutes using an ultrasonic disperser. Next, a sample solution is obtained by treating with a membrane filter having a pore size of 0.2 μm, 10 μL of this sample solution is injected into the apparatus together with the above carrier solvent, and the sample solution is detected and measured using a refractive index detector (RI detector). The molecular weight distribution of the sample is calculated using a calibration curve measured using monodisperse polystyrene standard particles. As a standard polystyrene sample for calibration curve measurement, a molecular weight manufactured by Pressure Chemical Co., Ltd. is 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1 .1 × 10 ⁵ , 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ were used, and at least about 10 standard polystyrene samples were measured, and a calibration curve was used. To create. A refractive index detector is used as the detector.

The content of the vinyl resin (a) in the binder resin is preferably 60 to 90% by mass, more preferably 70 to 86% by mass.

[Crystalline polyester resin (b)]
The crystalline polyester resin (b) is a known polyester resin obtained by a polycondensation reaction between a divalent or higher carboxylic acid (polyvalent carboxylic acid component) and a divalent or higher alcohol (polyhydric alcohol component). , Refers to a resin having crystallinity. The crystalline polyester resin (b) according to the present invention contains an aliphatic diol having 2 to 5 carbon atoms as a polyhydric alcohol component.

The melting point of the crystalline polyester resin (b) is preferably 55 ° C. or higher and 90 ° C. or lower, and more preferably 70 ° C. or higher and 85 ° C. or lower. When the melting point of the crystalline polyester resin is in the above range, sufficient low-temperature fixability can be obtained even during high-speed fixing. The melting point of the crystalline polyester resin can be controlled by the resin composition.

The melting point of the crystalline polyester resin (b) can be measured by differential scanning calorimetry (DSC).

For example, it can be obtained by using a differential scanning calorimeter "Diamond DSC" (manufactured by PerkinElmer). The measurement is carried out in the first heating process in which the temperature is raised from room temperature (25 ° C.) to 150 ° C. at an ascending / descending speed of 10 ° C./min and maintained at an isothermal temperature at 150 ° C. for 5 minutes. Measurement conditions (heating / cooling conditions) through which a cooling process of cooling to 0 ° C. and maintaining an isothermal temperature at 0 ° C. for 5 minutes and a second heating process of raising the temperature from 0 ° C. to 150 ° C. at an ascending / descending speed of 10 ° C./min are performed in this order. ). The above measurement is performed by enclosing 3.0 mg of the sample in an aluminum pan and setting it in the sample holder of the differential scanning calorimeter "Diamond DSC". Use an empty aluminum pan as a reference.

In the above measurement, the endothermic curve obtained by the first heating process is analyzed, and the top temperature of the endothermic peak derived from the crystalline polyester resin is defined as the melting point of the crystalline polyester resin (b).

<Multivalent carboxylic acid component>
As the polyvalent carboxylic acid component of the crystalline polyester resin (b), it is preferable to use an aliphatic dicarboxylic acid, and an aromatic dicarboxylic acid may be used in combination. As the aliphatic dicarboxylic acid, it is preferable to use a linear type. There is an advantage that the crystallinity is improved by using the linear type. The polyvalent carboxylic acid component may be used alone or in combination of two or more.

Examples of the aliphatic dicarboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelliic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonandicarboxylic acid (undecanedioic acid), and 1 , 10-decandicarboxylic acid (dodecanedioic acid), 1,11-undecanedicarboxylic acid (tridecanedioic acid), 1,12-dodecanediocarboxylic acid (tetradecanedioic acid), 1,13-tridecanedicarboxylic acid (pentadecanedioic acid) ), 1,14-Tetradecanedicarboxylic acid (hexadecanedioic acid), 1,16-hexadecandicarboxylic acid (octadecanedioic acid), 1,18-octadecandicarboxylic acid (eicosandioic acid) and other saturated aliphatic dicarboxylic acids. ..

Among the above-mentioned aliphatic dicarboxylic acids, an aliphatic dicarboxylic acid having 10 to 16 carbon atoms is preferable from the viewpoint of low-temperature fixability and control of compatibility with vinyl resin.

Examples of aromatic dicarboxylic acids that can be used with aliphatic dicarboxylic acids include phthalic acid, terephthalic acid, isophthalic acid, orthophthalic acid, t-butylisophthalic acid, 2,6-naphthalenedicarboxylic acid, and 4,4'-biphenyl. Dicarboxylic acid and the like can be mentioned. Among these, terephthalic acid, isophthalic acid, and t-butylisophthalic acid are preferably used from the viewpoint of availability and emulsification. In addition, trimellitic acid, pyromellitic acid and other trivalent or higher valent carboxylic acids, anhydrides of the above carboxylic acid compounds, alkyl esters having 1 to 3 carbon atoms and the like can also be used.

The polyvalent carboxylic acid component for forming the crystalline polyester resin (b) preferably has an aliphatic dicarboxylic acid content of 50 constituent mol% or more, more preferably 70 constituent mol% or more, and further. It is preferably 80 constituent mol% or more, and particularly preferably 100 constituent mol%. By setting the content of the aliphatic dicarboxylic acid in the polyvalent carboxylic acid component to 50 constituent mol% or more, the crystallinity of the crystalline polyester resin can be sufficiently ensured.

<Multivalent alcohol component>
The polyhydric alcohol component consists of an aliphatic diol having 2 to 5 carbon atoms. By using such an aliphatic diol, the compatibility with the vinyl resin (a) contained in the core portion is improved, and the crystalline polyester resin (b) can be finely dispersed, so that the toner is melted. It progresses faster and improves low-temperature fixability during high-speed fixing. When an aliphatic diol having 6 or more carbon atoms is used, the compatibility between the crystalline polyester resin (b) and the vinyl resin (a) is lowered, and the dispersibility of the crystalline polyester resin (b) in the core portion is lowered. The dispersion diameter (domain diameter) becomes large. Therefore, the melting of the toner is slowed down, and the low-temperature fixability at the time of high-speed fixing is deteriorated.

Examples of the aliphatic diol having 2 to 5 carbon atoms include ethylene glycol (1,2-ethanediol), 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, and 1,3-butanediol. , 1,4-Butanediol, 1,2-Pentanediol, 1,3-Pentanediol, 1,4-Pentanediol, 1,5-Pentanediol. As the aliphatic diol, it is preferable to use a linear type. There is an advantage that the crystallinity is improved by using the linear type. Aliphatic diols having 2 to 5 carbon atoms may be used alone or in combination of two or more.

In the crystalline polyester resin (b) according to the present invention, the carbon number of the polyhydric alcohol component constituting the crystalline polyester resin (b) is _Calcohol, and the carbon number of the polyvalent carboxylic acid component excluding the carboxyl group is C. _{When used as an acid} , it is preferable to satisfy the following formula (1).

Since the crystalline polyester resin (b) satisfying the above formula (1) is formed by using a polyhydric alcohol component and a polyvalent carboxylic acid component having different chain lengths, it has a chain having a short carbon number and a carbon number. The long chains are alternately bonded as polyester chains. Since such polyester chains have low regularity, the molecular chains of the crystalline polyester resin (b) do not fold excessively, and the dispersion diameter (domain diameter) at the core portion tends to be small. Therefore, the low-temperature fixability at the time of high-speed fixing is further improved.

When two or more kinds of multivalent carboxylic acid components are contained, the above C _acid is the carbon number of the polyvalent carboxylic acid component having the highest content (molar conversion). For the same rate, the number of carbons of the largest polycarboxylic acid component having a carbon number and C _acid.

Similarly, when two or more kinds of polyhydric alcohol components are contained, the _Calcohol is the carbon number of the polyhydric alcohol component having the highest content (molar equivalent). In the case of the same ratio, the carbon number of the polyhydric alcohol component having the largest carbon number is _Calcohol .

The ratio of the polyvalent carboxylic acid component to the polyhydric alcohol component used is the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] of the polyhydric alcohol component and the carboxyl group [COOH] of the polyvalent carboxylic acid component. ] Is preferably 1.5 / 1.0 to 1.0 / 1.5.

The method for producing the crystalline polyester resin is not particularly limited, and examples thereof include a method of polycondensing (esterifying) the polyvalent carboxylic acid component and the polyhydric alcohol component using a known esterification catalyst. If necessary, the pressure inside the reaction system may be reduced, and the reaction may be carried out while removing water and alcohol generated during polycondensation.

As catalysts that can be used in the production of crystalline polyester resins, alkali metal compounds such as sodium and lithium; compounds containing Group 2 elements such as magnesium and calcium; aluminum, zinc, manganese, antimony, titanium, tin, Examples thereof include metal compounds such as zirconium and germanium; phosphite compounds; phosphoric acid compounds; and amine compounds. Specifically, examples of the tin compound include dibutyltin oxide (dibutyltin oxide), tin octylate, tin dioctylate, and salts thereof. Titanium compounds include titanium alkoxides such as tetranormal butyl titanate (Ti (On-Bu) ₄ ), tetraisopropyl titanate, tetramethyl titanate, and tetrastearyl titanate; titanium acylates such as polyhydroxytitanium stearate; titanium tetra. Examples thereof include titanium chelates such as acetylacetonate, titanium lactate, and titanium triethanolaminate. Examples of the germanium compound include germanium dioxide and the like. Further, examples of the aluminum compound include oxides such as polyaluminum hydroxide, aluminum alkoxide, and tributylaluminate. These may be used individually by 1 type or in combination of 2 or more type.

The polymerization temperature is not particularly limited, and can be appropriately adjusted in order to obtain the desired product, and is preferably 70 to 250 ° C. The polymerization time is not particularly limited, but is preferably 0.5 to 20 hours. During the polymerization, the pressure inside the reaction system may be reduced, if necessary.

<Hybrid crystalline polyester resin>
In the present invention, the crystalline polyester resin preferably contains a hybrid crystalline polyester resin in which a crystalline polyester polymerized segment and a vinyl polymerized segment having a styrene-derived structural unit are chemically bonded. By containing the hybrid crystalline polyester resin, the compatibility with the vinyl resin (a) is improved and the dispersibility is improved, so that the low temperature fixability at the time of high-speed fixing is further improved.

The chemically bonded structure is not particularly limited, but it is preferable that the crystalline polyester polymerized segment is grafted with the vinyl polymerized segment as the main chain. That is, the hybrid crystalline polyester resin is preferably a graft copolymer having a vinyl polymerized segment as a main chain and a crystalline polyester polymerized segment as a side chain. With such a form, the orientation of the crystalline polyester polymerized segment can be further enhanced, and the crystallinity of the hybrid crystalline polyester resin can be further improved.

More specifically, as the hybrid crystalline polyester resin, a hybrid crystalline polyester resin in which a crystalline polyester polymerized segment as a side chain is bonded to a main chain of a styrene acrylic polymerized segment having a styrene-derived structural unit is preferable.

<Crystalline polyester polymerized segment>
The crystalline polyester polymerized segment refers to a portion derived from the crystalline polyester resin. That is, it refers to a molecular chain having the same chemical structure as that constituting the crystalline polyester resin.

The crystalline polyester polymerized segment is a portion derived from a known polyester resin obtained by a polycondensation reaction with a polyvalent carboxylic acid component and a polyhydric alcohol component similar to the above-mentioned crystalline polyester resin. Since the polyvalent carboxylic acid component and the polyhydric alcohol component constituting the crystalline polyester polymerized segment are the same as those of the above crystalline polyester resin (b), description thereof will be omitted here. Further, as described above, it is preferable that the above formula (1) is also satisfied with respect to the relationship between the carbon number of the polyhydric alcohol component and the carbon number of the polyvalent carboxylic acid component.

The content of the crystalline polyester polymerized segment is preferably 80 to 98% by mass, more preferably 90 to 95% by mass, based on the total amount of the hybrid crystalline polyester resin. Within the above range, sufficient crystallinity can be imparted to the hybrid crystalline polyester resin. The constituent components and the content ratio of each segment in the hybrid crystalline polyester resin can be specified by, for example, NMR measurement and methylation reaction Py-GC / MS measurement.

The hybrid crystalline polyester resin contains a vinyl polymerized segment containing a styrene-derived structural unit in addition to the crystalline polyester polymerized segment. The vinyl polymerization segment is not particularly limited as long as it contains a styrene-derived structural unit, but a styrene- (meth) acrylic acid ester polymerization segment (styrene acrylic polymerization segment) is preferable in consideration of plasticity at the time of heat fixing.

The styrene-acrylic polymerization segment is formed by addition polymerization of at least styrene and a (meth) acrylic acid ester monomer. Specific examples of the monomer capable of forming the styrene-acrylic polymerized segment include the same monomers as those described in the above-mentioned styrene-acrylic resin, and thus the description thereof will be omitted here.

The content of the styrene-derived structural unit in the vinyl-polymerized segment is preferably 40 to 95% by mass with respect to the total amount of the vinyl-polymerized segment. The content of the structural unit derived from the (meth) acrylic acid ester monomer in the vinyl polymerized segment is preferably 5 to 60% by mass with respect to the total amount of the vinyl polymerized segment.

Further, the vinyl polymerization segment is preferably addition-polymerized with a compound for chemically bonding to the crystalline polyester polymerization segment in addition to the styrene and (meth) acrylic acid ester monomer. Specifically, it is preferable to use a compound that ester-bonds with the hydroxyl group [-OH] derived from the polyhydric alcohol component or the carboxyl group [-COOH] derived from the polyvalent carboxylic acid component contained in the crystalline polyester polymerization segment. .. Therefore, the vinyl polymerization segment can be further polymerized with respect to the styrene and the (meth) acrylic acid ester monomer and further polymerized with a compound having a carboxyl group [-COOH] or a hydroxyl group [-OH]. It is preferable.

Such compounds include, for example, compounds having a carboxyl group such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, silicic acid, fumaric acid, maleic acid monoalkyl ester, and itaconic acid monoalkyl ester; 2-hydroxy. Ethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate , Polyethylene glycol mono (meth) acrylate and other compounds having a hydroxyl group can be mentioned.

The content of the structural unit derived from the above compound in the vinyl polymerized segment is preferably 0.5 to 20% by mass with respect to the total amount of the vinyl polymerized segment.

The method for forming the styrene-acrylic polymerization segment is not particularly limited, and examples thereof include a method of polymerizing a monomer using a known oil-soluble or water-soluble polymerization initiator. Specific examples of the oil-soluble polymerization initiator include the following azo-based or diazo-based polymerization initiators and peroxide-based polymerization initiators.

Examples of the azo or diazo polymerization initiator include 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, and 1,1'-azobis (cyclohexane-1). -Carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile and the like.

Examples of the peroxide-based polymerization initiator include benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, 2, Examples thereof include 4-dichlorobenzoyl peroxide, lauroyl peroxide, 2,2-bis- (4,5-t-butylperoxycyclohexyl) propane, and tris- (t-butylperoxy) triazine.

Further, when resin particles are formed by the emulsion polymerization method, a water-soluble radical polymerization initiator can be used. Examples of the water-soluble radical polymerization initiator include persulfates such as potassium persulfate and ammonium persulfate, azobisaminodipropane acetate, azobiscyanovaleric acid and its salts, and hydrogen peroxide.

The content of the vinyl polymerized segment is preferably 2 to 20% by mass, more preferably 5 to 10% by mass in the hybrid crystalline polyester resin. Within the above range, sufficient crystallinity can be imparted to the hybrid crystalline polyester resin.

(Manufacturing method of hybrid crystalline polyester resin)
The method for producing a hybrid crystalline polyester resin contained in the binder resin according to the present invention can form a polymer having a structure in which the crystalline polyester polymerization segment and the vinyl polymerization segment are chemically bonded. The method is not particularly limited. Specific examples of the method for producing the hybrid crystalline polyester resin include the methods (a) to (c) shown below.

(A) A method in which a vinyl polymerization segment is polymerized in advance and a polymerization reaction for forming a crystalline polyester polymerization segment is carried out in the presence of the vinyl polymerization segment to produce a hybrid crystalline polyester resin (b) Crystalline polyester polymerization A method of forming a segment and a vinyl polymerized segment, respectively, and combining them to produce a hybrid crystalline polyester resin. (C) A crystalline polyester polymerized segment is formed in advance, and the presence of the crystalline polyester polymerized segment. A method for producing a hybrid crystalline polyester resin by carrying out a polymerization reaction for forming a vinyl polymerization segment below.

Among these, the method (a) is preferable because it is easy to form a hybrid crystalline polyester resin having a structure in which a crystalline polyester polymerized segment is grafted on a vinyl polymerized segment, and the production process can be simplified. Further, in the method (a), since the vinyl polymerized segment is formed in advance and then the crystalline polyester polymerized segment is bonded, the orientation of the crystalline polyester polymerized segment tends to be uniform. Therefore, it is preferable because a hybrid crystalline polyester resin suitable for the toner of the present invention can be reliably formed.

The weight average molecular weight (Mw) of the crystalline polyester resin is preferably 5,000 to 100,000, more preferably 10,000 to 80,000, and particularly preferably 15,000 to 50,000. .. The number average molecular weight (Mn) is preferably 2,000 to 20,000, more preferably 3,000 to 15,000.

The content of the crystalline polyester resin (b) in the binder resin is preferably 5 to 20% by mass, more preferably 7 to 15% by mass. Within this range, the low-temperature fixability at the time of high-speed fixing becomes good, and the chargeability of the toner is also improved.

[Amorphous polyester resin (c)]
The toner of the present invention contains an amorphous polyester resin (c) in the shell portion. The amorphous polyester resin (c) is obtained by a polycondensation reaction using a polyvalent carboxylic acid component and a polyhydric alcohol component as raw materials, does not have a definite melting point, and has a relatively high glass transition temperature. It is a resin having (Tg). This can be confirmed by performing differential scanning calorimetry (DSC) on the amorphous polyester resin. Further, since it is different from the monomer constituting the crystalline polyester resin, it can be distinguished from the crystalline polyester resin by, for example, analysis such as NMR.

The amorphous polyester resin (c) according to the present invention has a bisphenol A propylene oxide adduct (hereinafter, also referred to as “BPA-PO”) and a bisphenol A ethylene oxide adduct (hereinafter, “BPA”) as polyhydric alcohol components. Also referred to as "-EO"). By containing BPA-PO and BPA-EO as the polyhydric alcohol component, the compatibility with the core portion is appropriately suppressed, and the shell portion has an appropriate flexibility, so that the heat-resistant storage property of the toner is improved. When BPA-PO is not contained as the polyhydric alcohol component, the shell portion has a structure that is too flexible, so that the heat-resistant storage property is lowered. Further, when BPA-EO is not contained as the polyhydric alcohol component, the flexibility of the shell portion cannot be obtained, and the low temperature fixability at the time of high-speed fixing is lowered.

The content of BPA-EO in the polyhydric alcohol component is preferably 5 to 45 mol%, more preferably 10 to 40 mol%, based on the total number of moles of the polyhydric alcohol component. Within such a range, the shell portion containing the amorphous polyester resin (c) has appropriate flexibility, so that low-temperature fixability is improved and the strength of the shell portion is maintained, so that heat resistance is maintained. Good storability.

The polyhydric alcohol component of the amorphous polyester resin (c) may contain other polyhydric alcohol components as long as it contains the above-mentioned BPA-PO and BPA-EO. Other polyhydric alcohol components include, for example, ethylene glycol, propylene glycol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol. , Neopentylene glycol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, bisphenol A, bisphenol F, hydrogenated bisphenol A, 1,3,5-benzenetriol, 1,2,4- Benzenetriol, 1,3,5-trihydroxymethylbenzene, glycerin, sorbitol, 2-butene-1,4-diol, 3-butene-1,4-diol, 2-butin-1,4-diol, 3- Butin-1,4-diol, 9-octadecene-7,12-diol and the like can be mentioned. These other polyhydric alcohols may be used alone or in combination of two or more.

The total content of BPA-PO and BPA-EO in the polyhydric alcohol component is preferably 50 constituent mol% or more, more preferably 70 constituent mol% or more, still more preferably 80 constituent mol% or more. The above is particularly preferable, and the content is 100% by mole. When the total content of BPA-PO and BPA-EO in the polyhydric alcohol component is in the above range, the effect of the present invention can be obtained more efficiently.

<Multivalent carboxylic acid component>
As the polyvalent carboxylic acid component of the amorphous polyester resin (c), it is preferable to use an unsaturated aliphatic polyvalent carboxylic acid, an aromatic polyvalent carboxylic acid, and derivatives thereof. A saturated aliphatic polyvalent carboxylic acid may be used in combination as long as it can form an amorphous polyester resin.

Examples of the unsaturated aliphatic polycarboxylic acid include itaconic acid, fumaric acid, maleic acid, 3-hexendioic acid, 3-octendioic acid, an alkyl group having 1 to 20 carbon atoms or 2 carbon atoms. Unsaturated aliphatic dicarboxylic acids such as succinic acid substituted with 20 or less alkenyl groups: 3-butene-1,2,3-tricarboxylic acid, 4-pentene-1,2,4-tricarboxylic acid, aconitic acid, etc. , Unsaturated aliphatic tricarboxylic acids such as 4-pentene-1,2,3,4-tetracarboxylic acid, and the like, and these lower alkyl esters and acid anhydrides are used. You can also do it.

Specific examples of the succinic acid substituted with an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms include dodecyl succinic acid, dodecenyl succinic acid, octenyl succinic acid, decenyl succinic acid and the like. Moreover, these lower alkyl esters and acid anhydrides can also be used.

Examples of the aromatic polyvalent carboxylic acid include phthalic acid, terephthalic acid, isophthalic acid, t-butylisophthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-phenylene diacetic acid, and 2,6-naphthalenedicarboxylic acid. Aromatic dicarboxylic acids such as acids, 4,4'-biphenyldicarboxylic acid, anthracendicarboxylic acid; 1,2,4-benzenetricarboxylic acid (trimeritic acid), 1,2,5-benzenetricarboxylic acid (trimesic acid), Aromatic tricarboxylic acids such as 1,2,4-naphthalene tricarboxylic acid and hemimeric acid; aromatic tetracarboxylic acids such as pyromellitic acid, 1,2,3,4-butanetetracarboxylic acid; aromatics such as melitric acid Hexacarboxylic acids and the like can be mentioned, and these lower alkyl esters and acid anhydrides can also be used.

Examples of the saturated aliphatic polyvalent carboxylic acid include the saturated aliphatic dicarboxylic acid mentioned in the section of [Crystalline Polyester Resin].

The method for producing the amorphous polyester resin (c) is not particularly limited, and examples thereof include a method of polycondensing (esterifying) the polyvalent carboxylic acid component and the polyhydric alcohol component using a known esterification catalyst. .. If necessary, the pressure inside the reaction system may be reduced, and the reaction may be carried out while removing water and alcohol generated during polycondensation. The temperature and time during polycondensation, the catalyst used, the ratio of the polyvalent carboxylic acid component to the polyhydric alcohol component, and the like are the same as in the case of the above crystalline polyester resin, and thus the description thereof will be omitted here. ..

The glass transition temperature (Tg) of the amorphous polyester resin (c) is preferably 30 to 80 ° C, more preferably 40 to 64 ° C. The glass transition temperature (Tg) can be measured by differential scanning calorimetry (DSC), and specifically, is a value measured using "Diamond DSC" (manufactured by PerkinElmer). The measurement procedure and measurement conditions are the same as the melting point of the crystalline polyester resin (b) described above. Based on the obtained DSC curve, the maximum slope is determined between the extension of the baseline before the rise of the first endothermic peak in the second temperature rise process and the rising portion of the first endothermic peak to the peak apex. The tangent line shown was drawn, and the intersection was defined as the glass transition temperature.

<Hybrid amorphous polyester resin>
In the toner according to the embodiment of the present invention, the amorphous polyester resin (c) is a hybrid non-hybrid in which an amorphous polyester polymerized segment and a vinyl polymerized segment having a styrene-derived structural unit are chemically bonded. It preferably contains a crystalline polyester resin. More specifically, the amorphous polyester resin (c) is a hybrid non-hybrid having a graft copolymer structure in which an amorphous polyester polymerized segment and a vinyl polymerized segment having a styrene-derived structural unit are chemically bonded. It preferably contains a crystalline polyester resin. By containing such a hybrid amorphous polyester resin, the affinity of the shell portion with respect to the vinyl resin (a) is appropriately increased while maintaining the compatibility between the core portion and the shell portion. Therefore, the shell portion is more easily attached to the core portion, and the heat-resistant storage property of the toner is further improved.

The amorphous polyester polymerized segment is a portion derived from a known polyester resin obtained by a polycondensation reaction with a polyvalent carboxylic acid component and a polyhydric alcohol component similar to the above-mentioned amorphous polyester resin. Specific examples of the polyvalent carboxylic acid component and the polyhydric alcohol component constituting the amorphous polyester polymerized segment are the same as those of the above-mentioned amorphous polyester resin, and thus description thereof will be omitted here.

The content of the amorphous polyester polymerized segment is preferably 80 to 98% by mass, more preferably 90 to 95% by mass, based on the total amount of the hybrid amorphous polyester resin. The constituent components and the content ratio of each segment in the hybrid amorphous polyester resin can be specified by, for example, NMR measurement and methylation reaction Py-GC / MS measurement.

The hybrid amorphous polyester resin contains a vinyl polymerized segment containing a styrene-derived structural unit in addition to the above-mentioned amorphous polyester polymerized segment. The vinyl polymerization segment is not particularly limited as long as it contains a styrene-derived structural unit, but a styrene- (meth) acrylic acid ester polymerization segment (styrene acrylic polymerization segment) is preferable in consideration of plasticity at the time of heat fixing.

The styrene-acrylic polymerization segment is formed by addition polymerization of at least styrene and a (meth) acrylic acid ester monomer. Specific examples of the monomer capable of forming the styrene-acrylic polymerized segment include the same monomers as those described in the above-mentioned styrene-acrylic resin, and thus the description thereof will be omitted here.

The content of the styrene-derived structural unit in the vinyl-polymerized segment is preferably 40 to 95% by mass with respect to the total amount of the vinyl-polymerized segment. The content of the structural unit derived from the (meth) acrylic acid ester monomer in the vinyl polymerized segment is preferably 5 to 60% by mass with respect to the total amount of the vinyl polymerized segment.

Further, the vinyl polymerization segment is preferably addition-polymerized with a compound for chemically bonding to the crystalline polyester polymerization segment in addition to the styrene and (meth) acrylic acid ester monomer. Specifically, it is preferable to use a compound that ester-bonds with the hydroxyl group [-OH] derived from the polyhydric alcohol component or the carboxyl group [-COOH] derived from the polyvalent carboxylic acid component contained in the crystalline polyester polymerization segment. .. Therefore, the vinyl polymerization segment can be further polymerized with respect to the styrene and the (meth) acrylic acid ester monomer and further polymerized with a compound having a carboxyl group [-COOH] or a hydroxyl group [-OH]. It is preferable.

Such compounds include, for example, compounds having a carboxyl group such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, silicic acid, fumaric acid, maleic acid monoalkyl ester, and itaconic acid monoalkyl ester; 2-hydroxy. Ethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate , Polyethylene glycol mono (meth) acrylate and other compounds having a hydroxyl group can be mentioned.

The content of the structural unit derived from the above compound in the vinyl polymerized segment is preferably 0.5 to 20% by mass with respect to the total amount of the vinyl polymerized segment.

The method for forming the styrene-acrylic polymerization segment is not particularly limited, and examples thereof include a method of polymerizing a monomer using a known oil-soluble or water-soluble polymerization initiator. Specific examples of the polymerization initiator are the same as those described in the above section of the hybrid crystalline polyester resin.

The content of the vinyl polymerized segment is preferably 2 to 20% by mass, more preferably 5 to 10% by mass in the hybrid amorphous polyester resin.

As a method for producing the hybrid amorphous polyester resin, an existing general scheme can be used. The following three are typical methods.

(1) A method of producing a hybrid amorphous polyester resin by prepolymerizing a vinyl polymerized segment and performing a polymerization reaction to form an amorphous polyester polymerized segment in the presence of the vinyl polymerized segment (2) A method of forming a sex polyester polymerized segment and a vinyl polymerized segment, respectively, and combining them to produce a hybrid amorphous polyester resin (3) The amorphous polyester polymerized segment is polymerized in advance, and the amorphous polyester polymerized segment is polymerized in advance. A method for producing a hybrid amorphous polyester resin by carrying out a polymerization reaction for forming a vinyl polymerized segment in the presence of a polyester polymerized segment.

The weight average molecular weight (Mw) of the amorphous polyester resin is not particularly limited, but is preferably 2,000 to 150,000, and more preferably 10,000 to 100,000. The number average molecular weight (Mn) of the amorphous polyester resin is not particularly limited, but is preferably 1,000 to 30,000, more preferably 5,000 to 25,000.

The content of the amorphous polyester resin (c) in the binder resin is preferably 5 to 20% by mass, more preferably 7 to 15% by mass. Within this range, heat-resistant storage is improved.

[Release agent]
The toner of the present invention contains a mold release agent (wax). Examples of the release agent include hydrocarbon waxes, ester waxes, natural product waxes, amide waxes and the like.

Examples of hydrocarbon waxes include low molecular weight polyethylene wax and polypropylene wax, as well as microcrystalline wax, Fishertroph wax, paraffin wax and the like.

Examples of ester-based waxes include behenyl behenate, ethylene glycol stearate, ethylene glycol behenic acid, neopentyl glycol stearate, neopentyl glycol behenic acid, 1,6-hexanediol stearate, 1,6. -Higher fatty acids such as hexanediol behenic acid ester, glycerin stearate ester, glycerin behenic acid ester, pentaerythritol tetrastearic acid ester, pentaerythritol tetrabechenic acid ester, stearyl citrate, behenyl citrate, stearyl ring acid, behenyl ring acid And esters with higher alcohols and the like. Among them, behenic behenate, pentaerythritol tetrabehenic acid ester, fatty acid polyglycerin ester, glycerin behenic acid ester, stearyl behenate and the like are preferable from the viewpoint of chargeability and fixability. These release agents can be used alone or in combination of two or more.

The melting point of the release agent is preferably 40 to 160 ° C, more preferably 60 to 100 ° C. By keeping the melting point within the above range, the heat-resistant storage stability of the toner is ensured, and stable toner image formation can be performed without causing cold offset or the like even when fixing is performed at a low temperature. The content of the release agent in the toner base particles is preferably 1 to 30% by mass, more preferably 3 to 20% by mass.

The method of containing the release agent in the toner is not particularly limited, and the release agent particle dispersion may be separately prepared and mixed with the dispersion of other components of the toner. However, when the raw material component of the binder resin is polymerized, it may be contained together. The former method has a technical effect for improving low temperature fixability, and the latter method has a technical effect for improving chargeability.

[Colorant]
The toner according to the present invention may contain a colorant. As the colorant, generally known dyes and pigments can be used.

Examples of colorants for obtaining black toner include carbon black, magnetic material, iron / titanium composite oxide black, and carbon black includes channel black, furnace black, acetylene black, thermal black, lamp black, and the like. Can be mentioned. Further, examples of the magnetic material include ferrite, magnetite and the like.

Examples of the colorant for obtaining the yellow toner include C.I. I. Dyes such as Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112, 162; I. Pigment Yellow 14, 17, 74, 93, 94, 138, 155, 180, 185 and the like.

Examples of the colorant for obtaining magenta toner include C.I. I. Dyes such as Solvent Red 1, 49, 52, 58, 63, 111, 122; C.I. I. Pigment Red 5, 48: 1, 53: 1, 57: 1, 122, 139, 144, 149, 166, 177, 178, 222 and the like.

Examples of the colorant for obtaining cyan toner include C.I. I. Dyes such as Solvent Blue 25, 36, 60, 70, 93, 95; C.I. I. Pigment Blue 1, 7, 15, 15, 15: 3, 60, 62, 66, 76 and the like.

As the colorant for obtaining the toner of each color, one kind or a combination of two or more kinds can be used for each color.

The content ratio of the colorant is preferably 0.5 to 20% by mass, more preferably 2 to 15% by mass in the toner base particles.

[Charge control agent]
The toner of the present invention may contain a charge control agent. As the charge control agent, various known compounds such as niglosin dyes, metal salts of naphthenic acid or higher fatty acids, alkoxylated amines, quaternary ammonium salt compounds, azo metal complexes, and salicylate metal salts can be used. ..

The amount of the charge control agent added is preferably 0.1 to 10% by mass with respect to 100% by mass of the binder resin in the finally obtained toner particles. The particle size of the charge control agent is preferably 10 to 1000 nm, 50 to 500 nm, and more preferably 80 to 300 nm in terms of number average primary particle size.

Examples of other additives include rhodamine dyes, triphenylmethane dyes, alkylamines and the like.

<Particle size of toner matrix particles>
The particle size of the toner matrix particles according to the present invention is preferably 3 to 8 μm in terms of volume-based median diameter. When the volume-based median diameter is within the above range, reproducibility of fine lines and high image quality of photographic images can be achieved, and toner consumption is reduced as compared with the case of using large particle size toner. be able to. This particle size can be controlled by the concentration of the flocculant, the fusion time, the composition of the polymer itself, and the like in the production method described later. The volume-based median diameter can be measured by, for example, "Coulter Multisizer 3" (manufactured by Beckman Coulter Co., Ltd.).

<Average circularity of toner matrix particles>
The toner matrix particles of the present invention are preferably produced by an emulsion aggregation method. In this case, the shape of the produced toner matrix particles (toner) becomes close to a true sphere. The average circularity of the toner matrix particles of the present invention represented by the following formula (2) is usually 0.91 or more. From the viewpoint of improving transfer efficiency and charging stability, the average circularity is preferably 0.920 to 0.995, more preferably 0.930 to 0.975.

The average circularity can be measured using, for example, an average circularity measuring device "FPIA-3000" (manufactured by Sysmex Corporation).

[External agent]
The toner according to the present invention may contain external additive particles. The external additive is not particularly limited, but inorganic particles having a number average primary particle size of about 2 to 800 nm are preferable. The type of the external additive is not particularly limited, and examples thereof include known inorganic particles and lubricants exemplified below. These external additives can be used alone or in combination of two or more.

As the inorganic particles, conventionally known particles can be used, and for example, silica, titania (titanium oxide), alumina, strontium titanate particles, hydrotalcite and the like are preferable. Further, if necessary, those obtained by hydrophobizing these inorganic particles can also be used.

It is also possible to use a lubricant to further improve the cleaning property and transferability. Examples of the lubricant include salts of zinc stearate, aluminum, copper, magnesium, calcium, etc., salts of zinc oleate, salts of manganese, iron, copper, magnesium, etc., salts of zinc palmitate, copper, magnesium, calcium, etc. Examples thereof include salts of zinc and calcium of linoleic acid, and salts of zinc and calcium of ricinolic acid.

The amount of the external additive added (when two or more kinds are used, the total amount) is preferably 0.1 to 10.0 parts by mass with respect to 100 parts by mass of the toner base particles.

[Method for manufacturing toner of the present invention]
The method for producing the toner of the present invention is not particularly limited, and examples thereof include known methods such as a kneading and pulverizing method, a suspension polymerization method, an emulsion aggregation method, a dissolution suspension method, a polyester elongation method, and a dispersion polymerization method.

Among these, it is preferable to adopt the emulsification and agglutination method from the viewpoint of particle size uniformity, shape controllability, and ease of core-shell structure formation. Hereinafter, the emulsification and agglutination method will be described.

(Emulsification agglutination method)
In the emulsion aggregation method, a dispersion of resin fine particles (hereinafter, also referred to as “resin particles”) dispersed by a surfactant or a dispersion stabilizer is mixed with a dispersion of toner particle constituents such as colorant particles. This is a method of forming toner particles by adding a coagulant to agglomerate the toner particles until the desired particle size of the toner is obtained, and then or at the same time agglomeration is performed to fuse the resin particles to control the shape.

The resin particles can be produced by, for example, an emulsification polymerization method, a miniemulsion polymerization method, a phase inversion emulsification method, or the like, or can be produced by combining several production methods.

When the toner particles contain an internal additive, the resin particles may contain the internal additive, or a dispersion of the internal additive particles consisting of only the internal additive is separately prepared and added. The agent particles may be agglomerated together when the resin particles are agglomerated.

When obtaining a core-shell type toner as in the present invention by the emulsification and aggregation method, first, the binder resin particles for the core portion and, if necessary, a colorant and / or a mold release agent are aggregated and fused. A core portion (core particles) is prepared, then resin particles for the shell portion are added to the dispersion liquid of the core portion, and the binding resin particles for the shell portion are aggregated and fused to the surface of the core portion. It can be obtained by forming a shell portion that covers the surface of the core portion.

When the toner is produced by the emulsification and agglutination method, the method for producing the toner according to the preferred embodiment is as follows.
(A) A step of preparing a vinyl resin particle dispersion, a crystalline polyester resin particle dispersion, and an amorphous polyester resin particle dispersion (hereinafter, also referred to as a preparation step).
(B) A step of mixing a vinyl resin particle dispersion liquid and a crystalline polyester resin particle dispersion liquid to aggregate and fuse them (hereinafter, also referred to as a core portion aggregation / fusion step), and (c) a resin constituting the core portion. A step of adding an amorphous polyester resin particle dispersion to a dispersion containing the above, and aggregating and fusing the amorphous polyester resin on the surface of the core to form a shell (hereinafter, also referred to as a shell forming step). ,
including.

Hereinafter, the steps (a) to (c) and the steps (d) to (f) optionally performed in addition to these steps will be described in detail.

(A) Preparation step The step (a) includes a vinyl resin particle dispersion preparation step, a crystalline polyester resin particle dispersion preparation step, and an amorphous polyester resin particle dispersion preparation step, and if necessary, Includes a colorant particle dispersion preparation step and a release agent particle dispersion preparation step.

(A-1) Preparation step of vinyl resin particle dispersion liquid In this step, the vinyl resin constituting the core portion of the toner is synthesized, and this vinyl resin is dispersed in an aqueous medium in the form of fine particles to prepare a dispersion liquid of vinyl resin particles. This is the process of preparation.

The vinyl resin particle dispersion liquid is, for example, (1) a method of dispersing the vinyl resin in an aqueous medium without using a solvent, and (2) dissolving the vinyl resin in a solvent such as ethyl acetate to prepare a solution and dispersing it. A method in which the solution is emulsified and dispersed in an aqueous medium using a machine and then subjected to solvent removal treatment. (3) Emulsion polymerization is carried out in an aqueous medium, and the liquid after the polymerization reaction is used as it is as a vinyl resin particle dispersion liquid. It can be prepared by a method, or the like.

Among them, the method (3) is preferable from the viewpoint that it can be prepared more easily. Hereinafter, the method (3) will be described.

(Aqueous medium)
In the present invention, the "aqueous medium" refers to a medium containing at least 50% by mass or more of water, and examples of components other than water include organic solvents that dissolve in water, such as methanol, ethanol, and the like. Examples thereof include isopropanol, butanol, acetone, methyl ethyl ketone, dimethylformamide, methyl cellsolve, and tetrahydrofuran. Of these, it is preferable to use an alcohol-based organic solvent such as methanol, ethanol, isopropanol, and butanol, which are organic solvents that do not dissolve the resin. Preferably, only water is used as the aqueous medium.

Further, the dispersion stabilizer may be dissolved in the aqueous medium, and a surfactant, resin particles, or the like may be added for the purpose of improving the dispersion stability of the oil droplets.

As the dispersion stabilizer, known ones can be used, for example, those soluble in acids and alkalis such as tricalcium phosphate are preferably used, or from an environmental point of view, an enzyme is used. It is preferable to use one that can be decomposed.

Examples of the resin particles for improving the dispersion stability include polymethyl methacrylate resin particles, polystyrene resin particles, and polystyrene-acrylonitrile resin particles.

The method for producing the vinyl resin is not particularly limited, but an emulsion polymerization method in which a resin monomer is added to an aqueous medium together with a polymerization initiator and the monomer is polymerized to obtain a dispersion of resin particles is preferable. Can be used.

In the emulsification polymerization method, the following seed polymerization is preferable. Specifically, a monomer for obtaining a vinyl resin is added to an aqueous medium together with a polymerization initiator and polymerized to obtain basic particles. Next, a radically polymerizable monomer and a polymerization initiator for obtaining a vinyl resin are added to the dispersion liquid in which the basic particles are dispersed, and the radically polymerizable monomer is seed-polymerized on the basic particles. It is preferable to use the method.

Further, for example, when the polymerization reaction is carried out in three stages, a dispersion liquid of resin particles is prepared by the first stage polymerization, and a resin monomer, a polymerization initiator, and a release agent if necessary are further contained in the dispersion liquid. Is added to carry out the second stage polymerization. The resin monomer and the polymerization initiator are further added to the dispersion liquid prepared by the second-stage polymerization to carry out the third-stage polymerization. At the time of the polymerization of the second stage and the third stage, the resin particles in the dispersion liquid generated by the previous polymerization can be used as a seed, and the monomer newly added to the resin particles can be further polymerized. It is possible to make the particle size of the resin particles uniform. Further, by using different monomers in the polymerization reaction of each stage, the structure of the resin particles can be made into a multi-layer structure, and it is easy to obtain the resin particles having the desired characteristics.

At the time of polymerization, it is preferable to heat the solution (reaction solution). The heating conditions are not particularly limited, but are usually about 60 to 100 ° C.

(Polymerization initiator)
As the polymerization initiator that can be used in the polymerization reaction, known ones can be used, for example, persulfates such as ammonium persulfate, sodium persulfate, potassium persulfate, and 2,2'-azobis (2-aminodipropane). ) Hydrochloride, 2,2'-azobis- (2-aminodipropane) nitrate, 4,7'-azobis-4-cyanovaleric acid, poly (tetraethylene glycol-2,2'-azobisisobutyrate) Such as azo compounds, peroxides such as hydrogen peroxide, and the like can be mentioned.

The amount of the polymerization initiator added varies depending on the target molecular weight and molecular weight distribution, but specifically, it should be in the range of 0.1 to 5.0% by mass with respect to the amount of the polymerizable monomer added. can.

(Chain transfer agent)
During the polymerization reaction, a chain transfer agent can be added from the viewpoint of controlling the molecular weight of the resin particles. Chain transfer agents that can be used include mercaptans such as n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan; mercaptopropionic acid esters such as n-octyl 3-mercaptopropionate, stearyl 3-mercaptopropionate; And styrene dimer and the like. These can be used alone or in combination of two or more.

The amount of the chain transfer agent added varies depending on the target molecular weight and the molecular weight distribution, but can be in the range of 0.1 to 5.0% by mass with respect to the amount of the polymerizable monomer added.

(Surfactant)
At the time of the polymerization reaction, a surfactant can be added from the viewpoint of preventing agglutination of resin particles in the dispersion liquid and maintaining a good dispersed state.

Examples of the surfactant include cationic surfactants such as dodecyl ammonium bromide and dodecyltrimethylammonium bromide, sodium stearate, sodium lauryl sulfate (sodium dodecyl sulfate), polyoxyethylene dodecyl ether sulfate sodium, and dodecylbenzene sulfonate sodium. Known surfactants such as anionic surfactants such as dodecylpolyoxyethylene ether and nonionic surfactants such as dodecylpolyoxyethylene ether and hexadecylpolyoxyethylene ether can be used. These can be used alone or in combination of two or more.

The particle size of the vinyl resin particles (oil droplets) in the vinyl resin particle dispersion prepared in this manner is a volume-based median diameter, preferably 60 to 1000 nm, and more preferably 80 to 500 nm. The volume-based median diameter of the oil droplets can be controlled by the magnitude of mechanical energy during emulsification and dispersion.

(A-2) Crystallized Polyester Resin Particle Dispersion Liquid Preparation Step In this step, a crystalline polyester resin constituting the core portion of the toner is synthesized, and the crystalline polyester resin is dispersed in an aqueous medium in the form of fine particles to form crystals. This is a step of preparing a dispersion of sex polyester resin particles. Since the method for producing the crystalline polyester resin is as described above, the description thereof will be omitted here.

The method for preparing the crystalline polyester resin particle dispersion liquid is, for example, a method of performing a dispersion treatment in an aqueous medium without using a solvent, or a method of dissolving a crystalline polyester resin in a solvent such as ethyl acetate to prepare a solution, and using a disperser. A method of emulsifying and dispersing the solution in an aqueous medium using the above solution and then performing a solvent removal treatment can be mentioned.

Specific examples of the aqueous medium, the dispersion stabilizer, the surfactant and the resin particles are as described in the above-mentioned (a-1) Vinyl resin particle dispersion liquid preparation step.

The crystalline polyester resin may contain a carboxyl group in its structure. In such a case, ammonia, sodium hydroxide, or the like may be added to the aqueous medium in order to ion dissociate the carboxyl group and stably emulsify it in the aqueous phase to facilitate the emulsification.

The above dispersion processing can be performed by utilizing mechanical energy, and the disperser is not particularly limited, and is a homogenizer, a low-speed shear disperser, a high-speed shear disperser, a friction disperser, and a high pressure. Examples include a jet type disperser, an ultrasonic disperser, a high pressure impact type disperser ultimateizer, and an emulsification disperser.

During dispersion, it is preferable to heat the solution. The heating conditions are not particularly limited, but are usually about 60 to 100 ° C.

The particle size of the crystalline polyester resin particles (oil droplets) in the crystalline polyester resin particle dispersion liquid prepared in this manner is a volume-based median diameter, preferably 60 to 1000 nm, and more preferably 80 to 500 nm. preferable. The volume-based median diameter can be measured by a dynamic light scattering method using "Microtrack UPA-150" (manufactured by Nikkiso Co., Ltd.). Further, the dispersion diameter of the oil droplets can be controlled by the magnitude of mechanical energy at the time of emulsification and dispersion.

The content of the crystalline polyester resin particles in the crystalline polyester resin particle dispersion liquid is preferably in the range of 10 to 50% by mass, more preferably in the range of 15 to 40% by mass, with the entire dispersion liquid as 100% by mass. Within such a range, the spread of the particle size distribution can be suppressed and the toner characteristics can be improved.

(A-3) Amorphous Polyester Resin Particle Dispersion Preparation Step In the amorphous polyester resin particle dispersion preparation step, the amorphous polyester resin constituting the shell portion of the toner is synthesized, and this amorphous polyester resin is used. This is a step of preparing a dispersion liquid of amorphous polyester resin particles by dispersing them in fine particles in an aqueous medium.

Since the method for producing the amorphous polyester resin is as described above, the description thereof will be omitted here. Further, since the method for preparing the dispersion liquid is the same as the content described in the above-mentioned (a-2) Crystallized polyester resin particle dispersion liquid preparation step, the description thereof will be omitted here.

The particle size of the amorphous polyester resin particles in the amorphous polyester resin particle dispersion is preferably in the range of 30 to 500 nm in terms of volume-based median diameter. The particle size of the amorphous polyester resin particles can be measured by a dynamic light scattering method using, for example, "Microtrack UPA-150" (manufactured by Nikkiso Co., Ltd.). The dispersion diameter of the oil droplets can be controlled by the magnitude of mechanical energy at the time of emulsification and dispersion.

(A-4) Colorant particle dispersion preparation step / Release agent particle dispersion preparation step The colorant particle dispersion preparation step is a step performed as necessary, and the colorant is made into fine particles in an aqueous medium. This is a step of dispersing and preparing a dispersion liquid of colorant particles. The release agent particle dispersion preparation step is a step performed as needed, and is a step of preparing a dispersion of release agent particles by dispersing the release agent in fine particles in an aqueous medium.

The aqueous medium is as described in (a-1) above, and a surfactant, resin particles, or the like may be added to the aqueous medium for the purpose of improving dispersion stability.

Dispersion of the colorant / release agent can be performed by utilizing mechanical energy, and the disperser is not particularly limited, and the one described in (a-1) above is used. be able to.

The content of the colorant in the colorant particle dispersion is preferably 10 to 50% by mass, more preferably 15 to 40% by mass. Within such a range, there is an effect of ensuring better color reproducibility. The content of the release agent particles in the release agent particle dispersion is preferably in the range of 10 to 50% by mass, and more preferably in the range of 15 to 40% by mass. Within such a range, a better effect of preventing hot offset and a better effect of ensuring separability can be obtained.

The dispersion diameter of the colorant particles in the colorant particle dispersion liquid is preferably in the range of 10 to 300 nm in terms of volume-based median diameter. The dispersion diameter of the colorant particles in the colorant particle dispersion liquid can be measured by a dynamic light scattering method using, for example, "Microtrack UPA-150" (manufactured by Nikkiso Co., Ltd.).

(B) Core agglomeration / fusion step In this core agglomeration / fusion step, the above-mentioned vinyl resin particles and crystalline polyester resin particles, and if necessary, colorant particles and / or a mold release agent are used in an aqueous medium. This is a step of aggregating the particles, aggregating the particles, and at the same time fusing these particles.

In this step, first, the vinyl resin particles and the crystalline polyester resin particles are mixed with the colorant particles and / or the release agent particles, if necessary, and these particles are dispersed in the aqueous medium. Next, after adding an alkali metal salt, a salt containing a Group 2 element, or the like as a coagulant, the vinyl resin particles and the crystalline polyester resin particles are heated at a temperature equal to or higher than the glass transition temperature to promote coagulation, and at the same time, the resin. Fuse the particles together.

Specifically, the vinyl resin particle dispersion and the crystalline polyester resin particle dispersion prepared in the above procedure are mixed with the colorant particle dispersion and / or the release agent particle dispersion, if necessary. By adding a flocculant such as magnesium chloride, the vinyl resin particles and the crystalline polyester resin particles are agglomerated with the colorant particles and / or the release agent particles as needed, and at the same time, the particles are fused to each other. The core portion of the toner is formed.

The flocculant used in this step is not particularly limited, but one selected from metal salts is preferably used. For example, salts of monovalent metals such as alkali metals such as sodium, potassium and lithium, salts of divalent metals such as calcium, magnesium, manganese and copper, salts of trivalent metals such as iron and aluminum, etc. There is. Specific examples of the salt include sodium chloride, potassium chloride, lithium chloride, calcium chloride, magnesium chloride, zinc chloride, copper sulfate, magnesium sulfate, manganese sulfate and the like, and among these, a divalent metal is particularly preferable. It is salt. The use of divalent metal salts can promote aggregation in smaller amounts. These flocculants can be used alone or in combination of two or more.

In the coagulation step, it is preferable to keep the standing time (time until the start of heating) left after adding the coagulant as short as possible. That is, after adding the coagulant, it is preferable to start heating the coagulation dispersion as soon as possible so that the temperature is equal to or higher than the glass transition temperature of the vinyl resin and the crystalline polyester resin. The reason for this is not clear, but there is a risk that the agglutination state of the particles will fluctuate with the passage of time, causing problems such as the particle size distribution of the obtained toner particles becoming unstable and the surface properties fluctuating. Because there is. The leaving time is usually 30 minutes or less, preferably 10 minutes or less. The temperature at which the flocculant is added is not particularly limited, but is preferably equal to or lower than the glass transition temperature of the vinyl resin and the crystalline polyester resin contained in the core portion.

Further, in the coagulation step, it is preferable to raise the temperature quickly by heating after adding the coagulant, and the rate of temperature rise is preferably 0.8 ° C./min or more. The upper limit of the temperature rising rate is not particularly limited, but is preferably 15 ° C./min or less from the viewpoint of suppressing the generation of coarse particles due to the rapid progress of fusion. Further, after the aggregation dispersion reaches a desired temperature, the temperature of the aggregation dispersion is maintained for a certain period of time, preferably until the volume-based median diameter becomes 4.5 to 7.0 μm, and fusion is performed. (First aging step).

(C) Shell portion forming step In order to obtain the toner having the core shell structure of the present invention, after the first aging step described above, a dispersion liquid of amorphous polyester resin particles forming the shell portion is further added, and described above. Amorphous polyester resin that forms a shell portion on the surface of the obtained core portion (core particles) is aggregated and fused. As a result, toner matrix particles having a core-shell structure can be obtained. Then, when the size of the aggregated particles reaches the target size, a salt such as an aqueous sodium chloride solution is added to stop the aggregation. After that, in order to further strengthen the aggregation and fusion of the shell portion to the surface of the core portion and to make the shape of the particles a desired shape, further heat treatment of the reaction system is performed until the shape of the particles becomes a desired shape. Good (second aging step). This second aging step may be performed until the average circularity of the toner particles having the core-shell structure is within the range of the average circularity.

This results in particle growth (aggregation of vinyl resin, crystalline polyester resin particles, amorphous polyester resin particles, and optionally colorant / release agent particles) and fusion (disappearance of interfaces between the particles). ) And can be effectively advanced, and the durability of the finally obtained toner particles can be improved.

(D) Cooling Step This cooling step is a step of cooling the dispersion liquid of the toner base particles. The cooling rate in the cooling treatment is not particularly limited, but is preferably 0.2 to 20 ° C./min. The cooling treatment method is not particularly limited, and examples thereof include a method of introducing a refrigerant from the outside of the reaction vessel for cooling, and a method of directly feeding cold water into the reaction system for cooling.

(E) Filtration, washing, and drying steps In the filtration step, the toner matrix particles are filtered out from the dispersion liquid. The filtration treatment method includes a centrifugal separation method, a vacuum filtration method using a nutche or the like, a filtration method using a filter press or the like, and is not particularly limited.

Next, deposits such as surfactants and flocculants are removed from the toner matrix particles (cake-like aggregates) filtered out by washing in the washing step. The washing treatment is carried out by washing with water until the electrical conductivity of the filtrate reaches, for example, 5 to 10 μS / cm level.

In the drying step, the washed toner matrix particles are dried. Examples of the dryer used in this drying step include known dryers such as a spray dryer, a flash jet dryer, a vacuum freeze dryer, and a vacuum dryer, and include a stationary shelf dryer, a mobile shelf dryer, and a fluidized layer. It is also possible to use a dryer, a rotary dryer, a stirring dryer and the like. The amount of water contained in the dried toner matrix particles is preferably 5% by mass or less, more preferably 2% by mass or less.

Further, when the dried toner matrix particles are agglutinated by a weak intermolecular attractive force, a crushing treatment may be performed. As the crushing processing device, a mechanical crushing device such as a jet mill, a Henschel mixer, a coffee mill, or a food processor can be used.

(F) Toner Treatment Step This step is a step of adding and mixing an external additive to the surface of the dried toner matrix particles as needed to prepare a toner. By adding the external additive, the fluidity and chargeability of the toner are improved, and the cleanability is improved.

[Developer]
For example, the toner of the present invention may contain a magnetic substance and be used as a one-component magnetic toner, may be mixed with a so-called carrier and used as a two-component developer, or a non-magnetic toner may be used alone. Any of these can be preferably used.

As the carrier constituting the two-component developer, magnetic particles made of metals such as iron, ferrite and magnetite, and conventionally known materials such as alloys of these metals with metals such as aluminum and lead can be used, in particular. It is preferable to use ferrite particles.

The carrier preferably has a volume average particle diameter of 15 to 100 μm, and more preferably 25 to 60 μm.

As the carrier, it is preferable to use a carrier further coated with a resin or a so-called resin-dispersed carrier in which magnetic particles are dispersed in the resin. The resin for coating is not particularly limited, and for example, an olefin resin, a cyclohexyl methacrylate-methyl methacrylate copolymer, a styrene resin, an acrylic resin, a styrene acrylic resin, a silicone resin, a polyester resin, a fluororesin, or the like is used. .. Further, the resin for forming the resin-dispersed carrier is not particularly limited, and known ones can be used. For example, acrylic resin, styrene acrylic resin, polyester resin, fluororesin, phenol resin and the like can be used. Can be done.

Hereinafter, typical embodiments of the present invention will be shown and the present invention will be further described, but of course, the present invention is not limited to these embodiments. Unless otherwise specified in the examples, "parts" represents "parts by mass" and "%" represents "% by mass".

The melting point of the crystalline polyester resin (b) and the glass transition temperature of the amorphous polyester resin (c) were determined using a differential scanning calorimeter "Diamond DSC" (manufactured by PerkinElmer). The measurement is carried out in the first heating process in which the temperature is raised from room temperature (25 ° C.) to 150 ° C. at an ascending / descending speed of 10 ° C./min and maintained at an isothermal temperature at 150 ° C. for 5 minutes. Measurement conditions (heating / cooling conditions) through which a cooling process of cooling to 0 ° C. and maintaining an isothermal temperature at 0 ° C. for 5 minutes and a second heating process of raising the temperature from 0 ° C. to 150 ° C. at an ascending / descending speed of 10 ° C./min are performed in this order. ). The above measurement was performed by enclosing 3.0 mg of the sample in an aluminum pan and setting it in the sample holder of the differential scanning calorimeter "Diamond DSC", and using an empty aluminum pan as a reference.

In the above measurement, the endothermic curve obtained by the first heating process was analyzed, and the top temperature of the endothermic peak derived from the crystalline polyester resin was defined as the melting point of the crystalline polyester resin (b). The glass transition temperature of the amorphous polyester resin (c) was determined using the DSC curve of the amorphous polyester resin (c) obtained under the same measurement procedure and measurement conditions as described above. Based on the DSC curve, an extension of the baseline before the rise of the first endothermic peak in the second temperature rise process and a tangent line showing the maximum slope between the rising portion of the first endothermic peak and the peak apex. Was subtracted, and the intersection was defined as the glass transition temperature.

The weight average molecular weight (Mw) of each resin contained in the binder resin was measured by a measuring method using the following gel permeation chromatography (GPC).

That is, using the apparatus "HLC-8220" (manufactured by Tosoh Corporation) and the column "TSKguardcolum + TSKgelSuperHZM-M3 series" (manufactured by Tosoh Corporation), while maintaining the column temperature at 40 ° C., tetrahydrofuran (THF) was used as the carrier solvent at a flow velocity. The flow was performed at 0.2 mL / min. The measurement sample was dissolved in tetrahydrofuran so as to have a concentration of 1 mg / mL under the dissolution conditions of treating at room temperature (25 ° C.) for 5 minutes using an ultrasonic disperser. Next, a sample solution is obtained by treating with a membrane filter having a pore size of 0.2 μm, 10 μL of this sample solution is injected into the apparatus together with the above carrier solvent, and the sample solution is detected and measured using a refractive index detector (RI detector). The molecular weight distribution of the sample was calculated using a calibration curve measured using monodisperse polystyrene standard particles. As a standard polystyrene sample for calibration curve measurement, a molecular weight manufactured by Pressure Chemical Co., Ltd. is 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1 .1 × 10 ⁵ , 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ were used, and at least about 10 standard polystyrene samples were measured, and a calibration curve was used. It was created. A refractive index detector was used as the detector.

[Preparation of vinyl resin particle dispersion liquid A1 (vinyl resin particle dispersion liquid A1 for core)]
(First stage polymerization)
In a 5 L reaction vessel equipped with a stirrer, a temperature sensor, a cooling tube, and a nitrogen introduction device, 8 parts by mass of sodium dodecyl sulfate and 3000 parts by mass of ion-exchanged water were charged, and the inside was stirred at a speed of 230 rpm under a nitrogen stream. The temperature was raised to 80 ° C. After the temperature was raised, a solution prepared by dissolving 10 parts by mass of potassium persulfate in 200 parts by mass of ion-exchanged water was added, the liquid temperature was set to 80 ° C. again, and a mixed solution of the following monomers was added dropwise over 1 hour:
Styrene 480.0 parts by mass n-butyl acrylate 250.0 parts by mass Methacrylic acid 68.0 parts by mass After dropping, polymerization was carried out by heating at 80 ° C. for 2 hours and stirring to obtain a vinyl resin particle dispersion liquid a1-1. Prepared.

(Second stage polymerization)
A solution prepared by dissolving 7 parts by mass of sodium dodecyl sulfate in 3000 parts by mass of ion-exchanged water was charged into a 5 L reaction vessel equipped with a stirrer, a temperature sensor, a cooling tube, and a nitrogen introduction device, and heated to 98 ° C. After heating, the vinyl resin particle dispersion liquid a1-1 prepared by the first-stage polymerization was dissolved in 300 parts by mass in terms of solid content, and the following monomer, chain transfer agent, and mold release agent were dissolved at 90 ° C. The mixture and was added:
Styrene 243.0 parts by mass 2-ethylhexyl acrylate 90.5 parts by mass Methacrylic acid 33.1 parts by mass n-octyl mercaptan (chain transfer agent) 5.5 parts by mass Behenyl behenate (release agent, melting point 73 ° C) 130. A dispersion containing emulsified particles (oil droplets) was prepared by performing a mixing and dispersion treatment for 1 hour with a mechanical disperser CLEARMIX (manufactured by M-Technique Co., Ltd.) having a circulation path of 0 parts by mass. A solution of a polymerization initiator in which 6 parts by mass of potassium persulfate is dissolved in 200 parts by mass of ion-exchanged water is added to this dispersion, and the system is heated and stirred at 78 ° C. for 1 hour to carry out polymerization. , Vinyl resin particle dispersion liquid a1-2 was prepared.

(Third stage polymerization)
After further adding 400 parts by mass of ion-exchanged water to the vinyl resin particle dispersion liquid a1-2 obtained by the second-stage polymerization and mixing well, 6.0 parts by mass of potassium persulfate was added to 400 parts by mass of ion-exchanged water. The solution dissolved in was added. Further, under a temperature condition of 81 ° C., a mixed solution of the following monomer and chain transfer agent was added dropwise over 1 hour:
Styrene 354.8 parts by mass n-butyl acrylate 143.2 parts by mass Methacrylic acid 52.0 parts by mass n-octyl mercaptan (chain transfer agent) 8.0 parts by mass After the dropping is completed, polymerization is carried out by heating and stirring for 2 hours. After that, the mixture was cooled to 28 ° C. to prepare a dispersion liquid A1 in which particles of the vinyl resin a1 were dispersed. The weight average molecular weight of the obtained vinyl resin a1 was 35,000.

[Preparation of vinyl resin particle dispersion liquid A2]
In the preparation of the vinyl resin particle dispersion liquid A1, the amount of the monomer added in the second stage polymerization was determined.
Styrene 90.0 parts by mass n-butyl acrylate 90.0 parts by mass n-behenyl acrylate 152.5 parts by mass 33.1 parts by mass methacrylate n-octyl mercaptan (chain transfer agent) 5.5 parts by mass behenyl behenate (separation) Mold, melting point 73 ° C.) A dispersion liquid A2 in which particles of vinyl resin a2 were dispersed was prepared in the same manner except that the volume was 130.0 parts by mass. The weight average molecular weight of the obtained vinyl resin a2 was 27,000.

[Preparation of vinyl resin particle dispersion liquid A3]
In the preparation of the vinyl resin particle dispersion liquid A1, the amount of the monomer added in the second stage polymerization was determined.
215.0 parts by mass of styrene n-hexyl acrylate 118.5 parts by mass 33.1 parts by mass of methacrylate n-octyl mercaptan (chain transfer agent) 5.5 parts by mass behenyl behenate (release agent, melting point 73 ° C) 130. A vinyl resin particle dispersion liquid A3 in which particles of the vinyl resin a3 were dispersed was prepared in the same manner except that the parts were set to 0 parts by mass. The weight average molecular weight of the obtained vinyl resin a3 was 33,000.

[Preparation of vinyl resin particle dispersion liquid A4]
In the preparation of the vinyl resin particle dispersion liquid A1, the amount of the monomer added in the second stage polymerization was determined.
Thiol 118.0 parts by mass n-hexyl methacrylate 216.0 parts by mass Methacrylate 33.1 parts by mass n-octyl mercaptan (chain transfer agent) 5.5 parts by mass Behenyl behenate (mold release agent, melting point 73 ° C) 130. A vinyl resin particle dispersion liquid A4 in which particles of the vinyl resin a4 were dispersed was prepared in the same manner except that the parts were set to 0 parts by mass. The weight average molecular weight of the obtained vinyl resin a4 was 29,000.

[Preparation of vinyl resin particle dispersion liquid A5]
In the preparation of the vinyl resin particle dispersion liquid A1, the amount of the monomer added in the second stage polymerization was determined.
Styrene 105.0 parts by mass n-butyl acrylate 100.0 parts by mass n-tricosanyl acrylate 129.0 parts by mass 33.1 parts by mass methacrylate n-octyl mercaptan (chain transfer agent) 5.5 parts by mass behenyl behenate (Release agent, melting point 73 ° C.) A vinyl resin particle dispersion liquid A5 in which particles of the vinyl resin a5 were dispersed was prepared in the same manner except that the volume was 130.0 parts by mass. The weight average molecular weight of the obtained vinyl resin a5 was 28,000.

[Preparation of vinyl resin particle dispersion liquid A6]
In the preparation of the vinyl resin particle dispersion liquid A1, the amount of the monomer added in the second stage polymerization was determined.
Styrene 225.0 parts by mass n-pentyl acrylate 109.0 parts by mass Methacrylate 33.1 parts by mass n-octyl mercaptan (chain transfer agent) 5.5 parts by mass Behenyl behenate (mold release agent, melting point 73 ° C) 130. A vinyl resin particle dispersion liquid A6 in which particles of the vinyl resin a6 were dispersed was prepared in the same manner except that the parts were set to 0 parts by mass. The weight average molecular weight of the obtained vinyl resin a6 was 31,000.

[Preparation of vinyl resin particle dispersion liquid A7]
In the preparation of the vinyl resin particle dispersion liquid A1, the amount of the monomer added in the second stage polymerization was determined.
Styrene 221.5 parts by mass n-butyl acrylate 110.0 parts by mass 33.1 parts by mass methacrylic acid n-octyl mercaptan (chain transfer agent) 5.5 parts by mass Behenyl behenate (mold release agent, melting point 73 ° C) 130. A vinyl resin particle dispersion liquid A7 in which particles of the vinyl resin a7 were dispersed was prepared in the same manner except that the parts were set to 0 parts by mass. The weight average molecular weight of the obtained vinyl resin a7 was 34,000.

[Preparation of vinyl resin particle dispersion liquid A8]
In the preparation of the vinyl resin particle dispersion liquid A1, the particles of the vinyl resin a8 are dispersed in the same manner except that methyl methacrylate is used instead of the styrene used in the first to third stage polymerizations. A resin particle dispersion A8 was prepared. The weight average molecular weight of the obtained vinyl resin a8 was 32,000.

The configurations of the dispersions A1 to A8 are shown in Table 1 below.

[Preparation of crystalline polyester resin particle dispersion liquid B1]
The raw material monomers and radical polymerization initiators of the following vinyl polymerization segments (styrene-acrylic polymerization segments, StAc segments) containing both reactive monomers were placed in a dropping funnel:
Styrene 34 parts by mass n-Butyl acrylate 12 parts by mass Acrylic acid 2 parts by mass Radical polymerization initiator (di-t-butyl peroxide) 7 parts by mass.

Further, the raw material monomers of the following crystalline polyester polymerization segments (CPEs segments) were placed in a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, and heated to 170 ° C. to dissolve them. :
Hexadecane diic acid 281 parts by mass 1,4-butanediol 94 parts by mass.

Next, the raw material monomer of the vinyl polymerized segment was added dropwise over 90 minutes under stirring, and after aging for 60 minutes, the raw material monomer of the unreacted vinyl polymerized segment was removed under reduced pressure (8 kPa). .. The amount of the monomer removed at this time was very small as compared with the amount of the monomer of the vinyl polymerized segment described above.

Then, 0.8 parts by mass of Ti (On-Bu) ₄ was added as an esterification catalyst, the temperature was raised to 235 ° C., the reaction was carried out under normal pressure (101.3 kPa) for 5 hours, and further reduced pressure (8 kPa). ) Was reacted for 1 hour.

Next, after cooling to 200 ° C., the reaction was carried out under reduced pressure (20 kPa) for 1 hour to obtain a crystalline polyester resin b1 which is a hybrid crystalline polyester resin. The crystalline polyester resin b1 contained 8% by mass of a polymerization segment (StAc segment) other than the CPEs segment with respect to the total amount thereof, and the CPEs segment was grafted to the StAc segment. The obtained crystalline polyester resin b1 had a weight average molecular weight of 20,000 and a melting point of 78 ° C.

The crystalline polyester resin b1 was melted in an amount of 30 parts by mass and transferred to an emulsification disperser "Cavitron CD1010" (manufactured by Eurotec Ltd.) at a transfer rate of 100 parts by mass per minute. At the same time as the transfer of the molten crystalline polyester resin b1, 70 parts by mass of the reagent ammonia water was added to the emulsion disperser "Cavitron CD1010" (manufactured by Eurotec Ltd.) in a separate aqueous solvent tank with ion-exchanged water. Diluted water with a concentration of 0.37% by mass of dilute ammonia was transferred at a transfer rate of 0.1 liters per minute while heating to 100 ° C. with a heat exchanger. Then, by operating this emulsification disperser under the conditions of a rotor rotation speed of 60 Hz and a pressure of 5 kg / cm ² , a dispersion liquid B1 of a crystalline polyester resin b1 having a solid content of 30% by mass was prepared. At this time, the volume-based median diameter of the particles of the crystalline polyester resin b1 contained in the dispersion liquid B1 was 200 nm.

[Preparation of crystalline polyester resin particle dispersions B2-5 and B7-9]
In the preparation of the crystalline polyester resin particle dispersion liquid B1, the crystalline polyester resins b2 to b5 and b7 to b7 to the same except that the raw material monomer and the addition amount of the CPEs segment were changed as shown in Table 2 below. Dispersions B2 to B5 and B7 to B9 of particles of b9 were obtained.

[Preparation of crystalline polyester resin particle dispersion liquid B6]
281 parts by mass of hexadecanedioic acid and 283 parts by mass of 1,4-butanediol were placed in a reaction vessel equipped with a stirrer, a thermometer, a cooling tube, and a nitrogen gas introduction tube. After replacing the inside of the reaction vessel with dry nitrogen gas, _{0.1 part by mass of Ti (On-Bu) 4} was added, and the reaction was carried out at about 180 ° C. for 8 hours under a nitrogen gas stream. Further, 0.2 parts by mass of Ti (On-Bu) ₄ was added, the temperature was raised to about 220 ° C., and the stirring reaction was carried out for 6 hours. The reaction was carried out to obtain a crystalline polyester resin b6.

In the preparation of the crystalline polyester resin particle dispersion liquid B1, a dispersion liquid B6 of particles of the crystalline polyester resin b6 was obtained in the same manner except that the crystalline polyester resin b6 obtained above was used.

[Preparation of crystalline polyester resin particle dispersion liquid B10]
In the preparation of the crystalline polyester resin particle dispersion liquid B6, the crystalline polyester resin particle dispersion liquid B10 was obtained in the same manner except that the raw material monomer of the crystalline polyester polymerized segment was changed as shown in Table 2 below.

The configurations of the dispersions B1 to B10 are shown in Table 2 below.

[Preparation of Amorphous Polyester Resin Particle Dispersion Liquid C1]
The raw material monomer and radical polymerization initiator of the following vinyl polymerization segment (StAc segment) containing both reactive monomers were placed in a dropping funnel:
Styrene 80 parts by mass n-Butyl acrylate 20 parts by mass Acrylic acid 10 parts by mass Radical polymerization initiator (di-t-butyl peroxide) 16 parts by mass.

Further, the raw material monomer of the following amorphous polyester polymerization segment (APEs segment) is placed in a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, and heated to 170 ° C. to dissolve it. rice field:
Bisphenol A Propylene Oxide 2 Mole Adduct (BPA-PO)
228.6 parts by mass Bisphenol A ethylene oxide 2 mol adduct (BPA-EO)
57.1 parts by mass Terephthalic acid 66.9 parts by mass Fumaric acid 47.4 parts by mass.

Next, the raw material monomer of the vinyl polymerized segment was added dropwise over 90 minutes under stirring, and after aging for 60 minutes, the raw material monomer of the unreacted vinyl polymerized segment was removed under reduced pressure (8 kPa). ..

Then, 0.4 parts by mass of Ti (On-Bu) ₄ was added as an esterification catalyst, the temperature was raised to 235 ° C., under normal pressure (101.3 kPa) for 5 hours, and further under reduced pressure (8 kPa). The reaction was carried out for 1 hour.

Next, after cooling to 200 ° C., the reaction was carried out under reduced pressure (20 kPa) until a desired softening point was reached. Then, the solvent was removed to obtain an amorphous polyester resin c1. The amorphous polyester resin c1 contains 8% by mass of a polymerization segment (StAc segment) other than the APEs segment with respect to the total amount thereof, and the hybrid amorphous polyester resin in the form in which the APEs segment is grafted to the StAc segment. Met. The obtained amorphous polyester resin c1 had a weight average molecular weight of 20,000 and a glass transition temperature of 60 ° C.

100 parts by mass of the obtained amorphous polyester resin c1 was dissolved in 400 parts by mass of ethyl acetate (manufactured by Kanto Chemical Co., Inc.). Furthermore, it is mixed with 638 parts by mass of a 0.26 mass% concentration sodium lauryl sulfate solution prepared in advance, and while stirring, it is used with an ultrasonic homogenizer "US-150T" (manufactured by Nippon Seiki Seisakusho Co., Ltd.) at V-LEVEL 300 μA for 30 minutes. Ultrasonic dispersion. Then, using a diaphragm vacuum pump "V-700" (manufactured by BUCHI) while heating to 40 ° C., ethyl acetate was completely removed while stirring under reduced pressure for 3 hours, and the solid content was 13.5. A dispersion liquid C1 of particles of amorphous polyester resin c1 of mass% was prepared.

[Preparation of Amorphous Polyester Resin Particle Dispersion Liquids C2 to C3 and C5 to C8]
In the preparation of the amorphous polyester resin particle dispersion liquid C1, the amount (molar ratio) of the polyhydric alcohol component added to the amorphous polyester resin segment was changed as shown in Table 3 below. Dispersions C2 to C3 and C5 to C8 of particles of crystalline polyester resins c2 to c3 and c5 to c8 were obtained.

[Preparation of Amorphous Polyester Resin Particle Dispersion Liquid C4]
The following amorphous polyester resin monomer was placed in a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and heated to 170 ° C. to dissolve it:
Bisphenol A Propylene Oxide 2 Mole Adduct (BPA-PO)
228.6 parts by mass Bisphenol A ethylene oxide 2 mol adduct (BPA-EO)
57.1 parts by mass Terephthalic acid 66.9 parts by mass Fumaric acid 47.4 parts by mass.

Under stirring, 0.4 parts by mass of Ti (On-Bu) _{4 was added as an esterification catalyst.} After reacting at 235 ° C. for 6 hours under a nitrogen gas stream, the mixture was cooled to 200 ° C., reacted under reduced pressure (20 kPa) for another 5 hours, and then desolvated to obtain an amorphous polyester resin c4. rice field. The weight average molecular weight of the obtained amorphous polyester resin c4 was 17,000, and the glass transition temperature was 57 ° C.

In the preparation of the amorphous polyester resin particle dispersion liquid C1, the amorphous polyester resin particle dispersion liquid C4 was obtained in the same manner except that the amorphous polyester resin c4 obtained above was used.

The configurations of the amorphous polyester resins c1 to c8 are shown in Table 3 below. The amount of BPA-EO and BPA-PO used is expressed as a ratio (unit: mol%) to the total number of moles of BPA-EO and BPA-PO used.

[Colorant particle dispersion]
90 parts by mass of sodium dodecyl sulfate was added to 1600 parts by mass of ion-exchanged water. While stirring this solution, 420 parts by mass of copper phthalocyanine (CI Pigment Blue 15: 3) was gradually added, and then dispersion treatment was performed using a stirrer "Clearmix" (manufactured by M Technique Co., Ltd.). To prepare an aqueous dispersion of colorant particles.

The volume-based median diameter of the colorant particles in the obtained aqueous dispersion was 110 nm.

(Example 1)
[Preparation of toner 1]
Vinyl resin particle dispersion A1 285 parts by mass (solid content equivalent), crystalline polyester resin particle dispersion liquid B1 40 parts by mass (solid content equivalent), dodecyldiphenyl ether in a reaction vessel equipped with a stirrer, temperature sensor, and cooling tube. After adding 1% by mass (solid content equivalent) of sodium disulfonic acid salt to the total amount of vinyl resin and crystalline polyester resin and 2000 parts by mass of ion-exchanged water, 5 mol / liter sodium hydroxide aqueous solution was added. Then, the pH was adjusted to 10.

Then, 30 parts by mass (in terms of solid content) of the aqueous dispersion of the colorant particles was added, and then an aqueous solution prepared by dissolving 60 parts by mass of magnesium chloride in 60 parts by mass of ion-exchanged water was poured over 10 minutes at 30 ° C. under stirring. Was added. Then, after leaving it for 3 minutes, the temperature rise was started, and the temperature of this system was raised to 80 ° C. over 60 minutes. After reaching 80 ° C., adjust the stirring speed so that the growth rate of the particle size is 0.01 μm / min, and adjust the particle size of the associated particles with “Colter Multisizer 3” (manufactured by Beckman Coulter Co., Ltd.). It was measured and grown until the volume-based median diameter was 6.0 μm.

Then, 37 parts by mass (solid content equivalent) of the amorphous polyester resin particle dispersion liquid C1 for the shell was added over 30 minutes, and when the supernatant of the reaction liquid became transparent, 190 parts by mass of sodium chloride was ion-exchanged. A dissolved aqueous solution was added to 760 parts by mass of water to stop particle growth. Further, the temperature is raised and the mixture is heated and stirred at 80 ° C. to promote the fusion of particles, and the average circularity of the toner is measured using the measuring device "FPIA-3000" (manufactured by Sysmex) (HPF detection). The average circularity was measured, and when the average circularity reached 0.970, the mixture was cooled to 30 ° C. at a cooling rate of 2.5 ° C./min.

Next, the operation of solid-liquid separation, redispersion of the dehydrated toner cake in ion-exchanged water, and solid-liquid separation was repeated three times for washing, and then dried at 40 ° C. for 24 hours to obtain toner matrix particles.

To 100 parts by mass of the obtained toner base particles, 0.6 parts by mass of hydrophobic silica (number average primary particle size = 12 nm, degree of hydrophobicity = 68) and hydrophobic titanium oxide (number average primary particle size = 20 nm, hydrophobicization). Degree = 63) Add 1.0 part by mass and mix with a "Henshell mixer" (manufactured by Mitsui Miike Kakoki Co., Ltd.) at a peripheral speed of 35 mm / sec and 32 ° C for 20 minutes, and then open 45 μm. Toner 1 was obtained by subjecting an external additive treatment for removing coarse particles using a sieve.

(Examples 2 to 19, Comparative Examples 1 to 2, Comparative Examples 5 to 6)
[Preparation of toners 2 to 21, 24 to 25]
In the production of the toner 1, the toner is similarly prepared in the same manner except that the combination of the vinyl resin particle dispersion liquid, the crystalline polyester resin particle dispersion liquid, and the amorphous polyester resin particle dispersion liquid is changed as shown in Table 4 below. 2-21, 24-25 were obtained.

(Comparative Example 3)
[Preparation of toner 22]
In the production of the toner 1, the non-crystalline polyester resin particle dispersion liquid C1 for the shell is not added, the fusion of the particles is promoted, and the average circularity measuring device of the toner "FPIA-3000" (manufactured by Sysmex). Toner 22 was obtained in the same manner except that when the average circularity reached 0.970, the toner 22 was cooled to 30 ° C. at a cooling rate of 2.5 ° C./min. ..

(Comparative Example 4)
[Preparation of toner 23]
In the production of the toner 1, the toner 23 was prepared in the same manner except that the amount of the crystalline polyester resin particle dispersion liquid B1 charged was 325 parts by mass (in terms of solid content) and the vinyl resin particle dispersion liquid A1 was not charged. Obtained.

[Preparation of developer]
To the toner 1 obtained above, a ferrite carrier coated with an acrylic resin and having a volume average particle diameter of 32 μm was added and mixed so that the toner concentration was 6% by mass. In this way, a developer 1 which is a two-component developer containing the toner 1 was produced.

Further, using toners 2 to 25, developing agents 2 to 25 were prepared in the same manner as described above.

[evaluation]
<Heat-resistant storage of toner>
Take 0.5 g of toner in a 10 mL glass bottle with an inner diameter of 21 mm, close the lid, and shake it 600 times at room temperature (25 ° C) using a shaker "Tap Denser KYT-2000" (manufactured by Seishin Enterprise Co., Ltd.). The bottle was left open for 2 hours in an environment with a temperature of 55 ° C. and a relative humidity of 35% RH. Next, place the entire amount of toner on a 48 mesh (opening 350 μm) sieve, being careful not to crush the toner agglomerates, set it on a “powder tester” (manufactured by Hosokawa Micron Co., Ltd.), and hold the bar. , Fixed with knob nut. The vibration intensity was adjusted to a feed width of 1 mm, and vibration was applied for 10 seconds. Then, the ratio (mass%) of the amount of toner that passed through the sieve was measured, the sieve passing rate was calculated by the following formula (3), and the heat-resistant storage property of the toner was evaluated. If the sieve passing rate is 50% or more, it is practical.

<Low temperature fixability during high speed fixing>
bizhub PRESS (registered trademark) 1250 (manufactured by Konica Minolta Co., Ltd.) has been modified so that the temperature of the heating belt immediately after the fixing nip during paper passing can be measured and the linear speed of fixing can be adjusted regardless of the basis weight of the paper. The developer used as a sample was loaded using the modified machine. In the modified machine, A4 size coated paper with a basis weight of 209 g was vertically fed at a paper passing speed of 570 mm / sec in an environment of normal temperature and humidity (temperature 20 ° C., relative humidity 50% RH). In a fixing experiment in which 100 A4 images having a solid black band-shaped image with a width of 10 mm in the direction perpendicular to the transport direction were continuously printed and fixed on coated paper, the fixing temperatures were set to 90 ° C, 95 ° C, ..., And 5 ° C. The temperature was set to increase to 210 ° C. in increments.

In each fixing experiment, the temperature dropped when the paper was passed, and the lowest temperature at that time was defined as the fixing temperature. The image printed at each fixing temperature was visually confirmed, and the lowest fixing temperature at which no image stain due to the fixing offset was confirmed was set as the minimum fixing temperature of the toner. It is practical if the minimum fixing temperature is 155 ° C. or lower.

Table 4 below shows the composition and evaluation results of the toners of Examples and Comparative Examples.

As is clear from Table 4 above, it was found that the toner of the example was excellent in heat-resistant storage property and low-temperature fixability at the time of high-speed fixing. The toner of Comparative Example 1 in which the polyhydric alcohol component of the crystalline polyester resin (b) has 6 carbon atoms, and Comparative Example 2 which does not have BPA-EO as the polyhydric alcohol component of the amorphous polyester resin (c). Toner has reduced low temperature fixability. The toner of Comparative Example 3 having no core-shell structure, the toner of Comparative Example 4 in which the vinyl resin does not have a structural unit derived from styrene, and BPA-PO as a polyhydric alcohol component of the amorphous polyester resin (c). No The toner of Comparative Example 5 had a reduced heat-resistant storage property. The toner of Comparative Example 6, which is the toner described in Japanese Patent Application Laid-Open No. 2015-049320, had both reduced low-temperature fixability and heat-resistant storage property.

Claims (6)

A core-shell type toner for static charge image development containing at least a binder resin and a mold release agent.
The binding resin is
Vinyl resin (a) having a structural unit derived from styrene,
A structural unit derived from a polycarboxylic acid component, a crystalline polyester resin (b), and polycarboxylic acid component containing a constituent unit derived from a polyhydric alcohol component consisting of aliphatic diols having 2 to 5 carbon atoms, a a structural unit derived from a non-crystalline polyester resin containing a constituent unit derived from a polyhydric alcohol component containing a propylene oxide adduct of bisphenol a and bisphenol a ethylene oxide adduct, a (c),
Including
A core-shell type for static charge image development, which has the vinyl resin (a) and the crystalline polyester resin (b) in the core portion of the toner, and the amorphous polyester resin (c) in the shell portion of the toner. toner. The core-shell type toner for developing an electrostatic charge image according to claim 1, wherein the vinyl resin (a) further has a structural unit derived from a (meth) acrylic acid alkyl ester represented by the following general formula (1).

In the above general formula (1), R1 is a hydrogen atom or a methyl group, and R2 is an alkyl group having 6 to 22 carbon atoms. 1. The content of the bisphenol A ethylene oxide adduct with respect to the total number of moles of the structural units derived from the polyhydric alcohol component constituting the amorphous polyester resin (c) is 10 to 40 mol%, claim 1. Alternatively, the core-shell type toner for developing an electrostatic charge image according to 2. The number of carbon atoms of the structural unit derived from the polyhydric alcohol component constituting the crystalline polyester resin (b) is defined as Calcohol.
6. Core-shell type toner for static charge image development.

Any of claims 1 to 4, wherein the crystalline polyester resin (b) contains a hybrid crystalline polyester resin in which a crystalline polyester polymerized segment and a vinyl polymerized segment having a structural unit derived from styrene are chemically bonded. The core-shell type toner for developing an electrostatic charge image according to item 1. Claims 1 to 5 include the amorphous polyester resin (c), which comprises a hybrid amorphous polyester resin in which an amorphous polyester polymerized segment and a vinyl polymerized segment having a structural unit derived from styrene are chemically bonded. The core-shell type toner for developing an electrostatic charge image according to any one of the above items.