JP2017003857A - Toner for electrostatic latent image development and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner for electrostatic latent image development which is hardly charged and attenuated and is excellent in heat-resistant storage property and fixability, and to provide a method for producing the same.SOLUTION: A toner for electrostatic latent image development contains a plurality of toner particles containing a binder resin. The toner particles contain a noncrystalline polyester resin, and a particulate crystalline polyester resin which are dispersed in the noncrystalline polyester resin, as binder resins. A dispersion diameter of the crystalline polyester resin is 40 nm or more and 150 nm or less. When phase delay of a probe of a scanning type probe microscope in the cross section of the toner particles has been measured in a dynamic mode of the scanning type probe microscope, a phase delay A of the probe on the noncrystalline polyester resin and a phase delay B of the probe on the crystalline polyester resin satisfy a relational expression of -22°≤B-A≤-13°.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electrostatic latent image developing toner and a method for producing the same.

  Known binder resins for toner include melt-kneaded crystalline resins and non-crystalline resins (non-crystalline resins) (for example, see Patent Document 1). The toner described in Patent Document 2 includes a first amorphous polyester resin (amorphous polyester resin B) and a second amorphous polyester resin (amorphous polyester resin A) as binder resins. And toner particles containing a crystalline polyester resin. Each of the second amorphous polyester resin and the crystalline polyester resin is dispersed in the first amorphous polyester resin.

International Publication No. 2005/111730 JP 2013-54178 A

  The toner using the binder resin described in Patent Document 1 tends to have poor fixability. The reason for this is considered to be that the compatibility of the plural types of resins used as the binder resin is not sufficient. In the toner described in Patent Document 2, the second amorphous polyester resin having a low glass transition point (Tg) is dispersed in the first amorphous polyester resin constituting the toner particles. For this reason, the toner described in Patent Document 2 tends to be inferior in heat resistant storage stability. Even if the techniques disclosed in Patent Documents 1 and 2 are used, it is difficult to provide a toner for developing an electrostatic latent image that is less likely to be charged and is excellent in heat-resistant storage stability and fixability.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a toner for developing an electrostatic latent image that hardly resists charge decay and is excellent in heat-resistant storage stability and fixability, and a method for producing the same.

  The electrostatic latent image developing toner according to the present invention includes a plurality of toner particles containing a binder resin. The toner particles contain an amorphous polyester resin and a particulate crystalline polyester resin dispersed in the amorphous polyester resin as the binder resin. The dispersion diameter of the crystalline polyester resin is 40 nm or more and 150 nm or less. When measuring the phase lag of the probe of the scanning probe microscope in the cross section of the toner particle in the dynamic mode of the scanning probe microscope, the phase lag A of the probe on the non-crystalline polyester resin and the The phase delay B of the probe on the crystalline polyester resin satisfies the relational expression “−22 ° ≦ B−A ≦ −13 °”.

  The method for producing a toner for developing an electrostatic latent image according to the present invention is a method for producing the toner for developing an electrostatic latent image, wherein the core material is melt-kneaded, the kneaded material is pulverized, the material is added, and the shell Layer formation. In the melt kneading of the core material, the core material containing at least an amorphous polyester resin and a crystalline polyester resin is melt kneaded to contain the crystalline polyester resin having a dispersion diameter not in the range of 40 nm to 150 nm. A kneaded product is obtained. In the pulverization of the kneaded product, the core is obtained by pulverizing the kneaded product. In the addition of the material, the core and the material of the shell layer are placed in an aqueous medium. In the formation of the shell layer, the dispersion diameter of the crystalline polyester resin in the core is set to 40 nm or more and 150 nm or less by polymerizing the material of the shell layer in the aqueous medium, and on the surface of the core. The shell layer is formed.

  According to the present invention, it is possible to provide a toner for developing an electrostatic latent image that hardly resists charging and has excellent heat-resistant storage stability and fixability and a method for producing the same.

It is a figure which shows an example of the histogram measured in the dynamic mode of the scanning probe microscope regarding the crystalline polyester resin and amorphous polyester resin which are contained in the toner which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail. The toner according to the exemplary embodiment can be suitably used for developing an electrostatic latent image, for example, as a positively chargeable toner. The toner of the present exemplary embodiment is a powder that includes a plurality of toner particles (each having a configuration described later). The toner may be used as a one-component developer. Further, a two-component developer may be prepared by mixing a toner and a carrier using a mixing device (more specifically, a ball mill or the like). In order to form a high-quality image, it is preferable to use a ferrite carrier as a carrier. In order to form a high-quality image over a long period of time, it is preferable to use a magnetic carrier that includes a carrier core and a resin layer that covers the carrier core. In order to produce a magnetic carrier, the carrier core may be formed of a magnetic material, or magnetic particles may be dispersed in the resin layer. In order to form a high-quality image, the amount of toner in the two-component developer is preferably 5 parts by mass or more and 15 parts by mass or less, and 8 parts by mass or more and 12 parts by mass with respect to 100 parts by mass of the carrier. The following is more preferable.

  The toner according to the exemplary embodiment can be used for image formation in, for example, an electrophotographic apparatus (image forming apparatus). Hereinafter, an example of an image forming method using an electrophotographic apparatus will be described.

  First, an electrostatic latent image is formed on a photoconductor (for example, a surface layer portion of a photoconductor drum) based on image data. Next, the formed electrostatic latent image is developed using a developer containing toner. In the developing step, charged toner is attached to the electrostatic latent image to form a toner image on the photoreceptor. In the subsequent transfer step, the toner image on the photosensitive member is transferred to an intermediate transfer member (for example, a transfer belt), and then the toner image on the intermediate transfer member is further transferred to a recording medium (for example, paper). Thereafter, the toner is heated to fix the toner on the recording medium. As a result, an image is formed on the recording medium. For example, a full color image can be formed by superposing four color toner images of black, yellow, magenta, and cyan.

The toner according to the exemplary embodiment is an electrostatic latent image developing toner having the following configuration (hereinafter referred to as a basic configuration).
(Basic toner configuration)
The electrostatic latent image developing toner includes a plurality of toner particles containing a binder resin. The toner particles contain, as a binder resin, an amorphous polyester resin and a particulate crystalline polyester resin dispersed in the amorphous polyester resin. The dispersion diameter of the crystalline polyester resin is 40 nm or more and 150 nm or less. When the phase lag of the probe of the scanning probe microscope in the cross section of the toner particle is measured in the dynamic mode of the scanning probe microscope, the phase lag A of the probe on the non-crystalline polyester resin and the crystalline polyester resin And the phase lag B of the probe satisfy the relational expression “−22 ° ≦ B−A ≦ −13 °”. The dispersion diameter of the crystalline polyester resin is the major axis diameter of the particles in the projected image measured by the same method as in the examples described later or an alternative method thereof.

  The crystalline polyester resin and the non-crystalline polyester resin can be distinguished based on the magnitude of the phase delay of the probe when scanning in the dynamic mode of the scanning probe microscope. The phase delay of the probe is a phase delay of the output signal of the probe with respect to an input signal for vibrating the probe (for example, an excitation signal to the piezoelectric element of the cantilever). The sign of the phase delay being negative (-) indicates that the probe output signal is delayed with respect to the input signal, and the numerical value of the phase delay indicates the degree of delay. Since the crystalline polyester resin is softer than the non-crystalline polyester resin, the phase delay of the probe tends to be larger than that of the non-crystalline polyester resin. The method for measuring the phase delay of the probe is the method shown in the examples described later or an alternative method thereof. The phase delay of the probe related to the polyester resin can be adjusted by changing the type or amount (blending ratio) of the material (for example, alcohol and / or carboxylic acid) for synthesizing the polyester resin.

  The inventor believes that, among the above-described basic configurations, the phase lag A and the phase lag B satisfy the relational expression “−22 ° ≦ B−A ≦ −13 °”. It was found to be effective for achieving both (see Table 1 and Table 2 described later). FIG. 1 shows an example of a histogram actually measured in the dynamic mode of the scanning probe microscope for the crystalline polyester resin and the non-crystalline polyester resin contained in the toner having the above-described basic configuration. In the histogram, a peak derived from the amorphous polyester resin and a peak derived from the crystalline polyester resin are shown. In the example of FIG. 1, the phase delay A is −93 ° (peak phase delay value derived from the amorphous polyester resin), and the phase delay B is −114 ° (peak phase derived from the crystalline polyester resin). The value of the delay). Therefore, in the example of FIG. 1, “BA” (hereinafter referred to as a crystalline-noncrystalline phase difference) in the above-described basic configuration is −21 °, and the relational expression “−22 ° ≦ B −A ≦ −13 ° ”is satisfied.

  In order to improve the low-temperature fixability of the toner, the crystallinity index of the crystalline polyester resin is preferably 0.90 or more and 1.50 or less. A crystalline polyester resin having such a crystallinity index is excellent in sharp melt property. The crystallinity index is the ratio of the softening point (Tm) to the melting point (Mp) (= Tm / Mp). The measuring methods of Mp and Tm are the same methods as the examples described later or alternative methods thereof. For amorphous polyester resins, it is often impossible to measure a clear Mp. The crystallinity index of the polyester resin can be adjusted by changing the type or amount of a material (for example, alcohol and / or carboxylic acid) for synthesizing the polyester resin.

  In order to improve the heat-resistant storage stability and chargeability (particularly, charge attenuation characteristics) of the toner, the inventor has that the dispersion diameter of the crystalline polyester resin in the toner core is 40 nm or more and 150 nm or less in the above-described basic configuration. (See Tables 1 and 2 described later). If the crystalline polyester resin and the non-crystalline polyester resin are compatible with each other and the dispersion diameter of the crystalline polyester resin in the toner core becomes too small, the heat-resistant storage stability of the toner is considered to deteriorate. On the other hand, if the dispersion diameter of the crystalline polyester resin in the toner core becomes too large, it is considered that the toner is likely to attenuate the charge.

In order for the toner to have the above-described basic configuration, the SP value (SP _A ) of the amorphous polyester resin and the SP value (SP _B ) of the crystalline polyester resin are expressed by the relational expression “0.2 J / cm ³ ≦ | It is preferable to satisfy “SP _A −SP _B | ≦ 1.0 J / cm ³ ”. The difference between the SP value of the amorphous polyester resin and the SP value of the crystalline polyester resin (hereinafter referred to as crystalline-noncrystalline SP value difference) is 0.2 J / cm ³ or more and 1.0 J / cm ³ It is considered that the non-crystalline polyester resin and the crystalline polyester resin are appropriately compatible with each other.

The SP values (SP _A and SP _B ) in the above relational expressions are SP values (solubility parameters) calculated according to the Collman method (see Document A below). The SP value of the polyester resin can be adjusted by changing the type or amount of a material (for example, alcohol and / or carboxylic acid) for synthesizing the polyester resin.
Reference A: M. M.M. Collman, 2 others (Pennsylvania State University), "Specific Interactions and the Misc. Of Polymer Blends" (USA), Technological Publishing, 1991

  The toner particles contained in the toner may be toner particles not having a shell layer (hereinafter referred to as non-capsule toner particles) or toner particles having a shell layer (hereinafter referred to as capsule toner particles). There may be. However, the above basic configuration is particularly useful when the toner particles contained in the toner are capsule toner particles. Hereinafter, an embodiment in which the toner particles contained in the toner are capsule toner particles will be described.

  Toner particles (capsule toner particles) contained in the toner according to the present embodiment include a core (hereinafter referred to as a toner core) and a shell layer (capsule layer) formed on the surface of the toner core. The shell layer is substantially composed of a resin. An external additive may adhere to the surface of the toner core or shell layer. The shell layer may cover the entire surface of the toner core or may partially cover the surface of the toner core. A plurality of shell layers may be laminated on the surface of the toner core. If not necessary, the external additive may be omitted. Hereinafter, the toner particles before the external additive adheres are referred to as toner mother particles. A material for forming the shell layer is referred to as a shell material. In non-capsule toner particles, a toner core in capsule toner particles described later can be used as toner base particles.

  In order for the toner to have the above-described basic configuration, it is preferable that the toner core is produced by a dry method and the shell layer is formed on the surface of the toner core by a wet method. As the dry method, a pulverization method is particularly preferable. The pulverization method is a method of obtaining a powder (for example, a toner core) through a step of obtaining a kneaded product by melting and kneading a plurality of types of materials (resins and the like) and a step of pulverizing the obtained kneaded product. A polymerization method is particularly preferable as the wet method. The polymerization method is a method of synthesizing a resin by polymerizing a material on the surface of a substrate (for example, a toner core) in a liquid (for example, an aqueous medium).

  When a toner core is produced by a dry method, the toner core is less likely to agglomerate than when a toner core is produced by a wet method such as an agglomeration method. The reason for this is considered to be that the contact time between the particles is shorter when the powder dispersion is stirred than when the dry powder is stirred. In addition, by preparing the toner core by a dry method, it becomes easy to uniformly mix the crystalline polyester resin and the amorphous polyester resin in the toner core.

  Further, after the toner core is prepared by a dry method, a shell layer is formed on the surface of the toner core by a wet method, so that the dispersion diameter of the crystalline polyester resin in the toner core can be easily adjusted. The dispersion diameter of the crystalline polyester resin in the toner core can be increased by heat during the formation of the shell layer (specifically, during the polymerization reaction of the shell material). Further, aggregation of the toner core can be suppressed by heating the toner core in the liquid.

  In order to easily adjust the dispersion diameter of the crystalline polyester resin in the toner core, it is preferable to form a shell layer in an aqueous medium. When the toner core is heated in the aqueous medium, the amorphous polyester resin tends to move to the surface of the toner core, and the crystalline polyester resin tends to move inside the toner core. The reason for this is considered to be that the amorphous polyester resin has stronger hydrophilicity than the crystalline polyester resin. The aqueous medium is a medium containing water as a main component (more specifically, pure water or a mixed liquid of water and a polar medium). The aqueous medium may function as a solvent. A solute may be dissolved in the aqueous medium. The aqueous medium may function as a dispersion medium. The dispersoid may be dispersed in the aqueous medium. As a polar medium in the aqueous medium, for example, alcohol (more specifically, methanol or ethanol) can be used.

  In order to achieve both heat-resistant storage stability and low-temperature fixability of the toner, the shell layer preferably covers an area of 50% to 99% of the surface area of the toner core, and is 70% to 95%. More preferably, the area is covered. In order to achieve both heat-resistant storage stability and low-temperature fixability of the toner, the maximum thickness of the shell layer is preferably 1 nm or more and 100 nm or less.

In order to achieve both the heat resistant storage stability and the low-temperature fixability of the toner, the volume median diameter (D ₅₀ ) of the toner is preferably 1 μm or more and less than 10 μm. The method of measuring the volume median diameter (D ₅₀₎ is the method or the alternative method shown in examples described later.

  Next, the toner core (binder resin and internal additive), shell layer, and external additive will be described in order. Depending on the use of the toner, unnecessary components may be omitted. Note that the evaluation results (values indicating shape, physical properties, etc.) regarding the powder (more specifically, the toner core, toner base particles, external additive, toner, etc.) are a considerable number of particles unless otherwise specified. Is the number average of the values measured for. Further, the particle diameter of the powder is the equivalent-circle diameter of the primary particles (the diameter of a circle having the same area as the projected area of the particles) unless otherwise specified. Hereinafter, a compound and its derivatives may be generically named by adding “system” after the compound name. When the name of a polymer is expressed by adding “system” after the compound name, it means that the repeating unit of the polymer is derived from the compound or a derivative thereof. Acrylic and methacrylic are sometimes collectively referred to as “(meth) acrylic”.

<Preferable thermoplastic resin>
Examples of the thermoplastic resin constituting the toner particles (particularly, the toner core or shell layer) include styrene resins, acrylic resins (more specifically, acrylic ester polymers, methacrylic ester polymers, or poly Methyl methacrylate (PMMA), etc.), olefin resin (more specifically, polyethylene resin or polypropylene resin, etc.), vinyl resin (more specifically, vinyl chloride resin, polyvinyl alcohol, vinyl ether resin, or N-vinyl). Resins), polyester resins, polyamide resins, or urethane resins, or copolymers having one or more repeating units derived from the same monomer as the repeating units of any of these homopolymers (more Specifically, styrene-acrylic acid resin or styrene-butadiene resin Etc.) can be suitably used.

  The thermoplastic resin can be obtained by condensation polymerization or co-condensation polymerization of one or more thermoplastic monomers (more specifically, an acrylic acid monomer or a styrene monomer).

  The styrene-acrylic acid resin is a copolymer of one or more styrene monomers and one or more acrylic monomers. In order to synthesize a styrene-acrylic acid resin, for example, a styrene monomer and an acrylic acid monomer as shown below can be suitably used. By using an acrylic acid monomer, a carboxyl group can be introduced into the styrene-acrylic acid resin. Further, by using a monomer having a hydroxyl group (more specifically, p-hydroxystyrene, m-hydroxystyrene, (meth) acrylic acid hydroxyalkyl ester, or the like), the hydroxyl group can be introduced into the styrene-acrylic acid resin. . The acid value of the styrene-acrylic acid resin obtained can be adjusted by adjusting the amount of the acrylic acid monomer used. Moreover, the hydroxyl value of the styrene-acrylic acid-type resin obtained can be adjusted by adjusting the usage-amount of the monomer which has a hydroxyl group.

  Suitable examples of the styrenic monomer include styrene, α-methylstyrene, p-hydroxystyrene, m-hydroxystyrene, vinyltoluene, α-chlorostyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, Or p-ethylstyrene is mentioned.

  Preferable examples of the acrylic acid monomer include (meth) acrylic acid, (meth) acrylic acid alkyl ester, or (meth) acrylic acid hydroxyalkyl ester. Suitable examples of the (meth) acrylic acid alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) acrylate, and (meth) acrylic. Examples include n-butyl acid, iso-butyl (meth) acrylate, or 2-ethylhexyl (meth) acrylate. Suitable examples of the (meth) acrylic acid hydroxyalkyl ester include 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, or (meth) acrylic. The acid 4-hydroxybutyl is mentioned.

  The polyester resin can be obtained by polycondensation or copolycondensation of alcohol and carboxylic acid. As the alcohol for synthesizing the polyester resin, for example, dihydric alcohols (more specifically, diols or bisphenols) as shown below or trihydric or higher alcohols can be suitably used. As the carboxylic acid for synthesizing the polyester resin, for example, divalent carboxylic acids or trivalent or higher carboxylic acids as shown below can be suitably used. Moreover, when synthesizing the polyester resin, the acid value and the hydroxyl value of the polyester resin can be adjusted by changing the amount of alcohol used and the amount of carboxylic acid used. When the molecular weight of the polyester resin is increased, the acid value and hydroxyl value of the polyester resin tend to decrease.

  Suitable examples of diols include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, Examples include 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, or polytetramethylene glycol.

  Preferable examples of bisphenols include bisphenol A, hydrogenated bisphenol A, polyoxyethylene bisphenol A ether, or polyoxypropylene bisphenol A ether.

  Preferable examples of trihydric or higher alcohols include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butane. Triol, 1,2,5-pentanetriol, glycerol, diglycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, or 1,3,5- Trihydroxymethylbenzene is mentioned.

  Preferable examples of the divalent carboxylic acid include suberic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, adipic acid, sebacic acid, azelaic acid , Malonic acid, succinic acid, alkyl succinic acid (more specifically, n-butyl succinic acid, isobutyl succinic acid, n-octyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid, etc.), or alkenyl succinic acid (More specifically, n-butenyl succinic acid, isobutenyl succinic acid, n-octenyl succinic acid, n-dodecenyl succinic acid, or isododecenyl succinic acid, etc.).

  Preferred examples of the trivalent or higher carboxylic acid include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) Examples include methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, or empole trimer acid.

  Note that the divalent or trivalent or higher carboxylic acid may be transformed into an ester-forming derivative (more specifically, an acid halide, an acid anhydride, or a lower alkyl ester). Here, “lower alkyl” means an alkyl group having 1 to 6 carbon atoms.

<Preferable thermosetting resin>
Examples of the thermosetting resin constituting the toner particles (particularly, the shell layer) include melamine resin, urea resin, sulfonamide resin, glyoxal resin, guanamine resin, aniline resin, polyimide resin (more specifically, Specifically, a maleimide polymer or a bismaleimide polymer) or a xylene-based resin can be preferably used.

  The thermosetting resin can be obtained by polycondensation or copolycondensation of one or more thermosetting monomers. Moreover, a thermosetting resin can also be synthesize | combined with a thermoplastic monomer by using a crosslinking agent.

  Preferable examples of the thermosetting monomer include methylol melamine, melamine, methylolated urea (more specifically, dimethylol dihydroxyethylene urea), urea, benzoguanamine, acetoguanamine, or spiroguanamine.

[Toner core]
The toner core contains a binder resin. The toner core may contain internal additives (for example, a colorant, a release agent, a charge control agent, and magnetic powder).

(Binder resin)
In the toner core, the binder resin generally occupies most of the components (for example, 85% by mass or more). For this reason, it is considered that the properties of the binder resin greatly affect the properties of the entire toner core. For example, when the binder resin has an ester group, a hydroxyl group, an ether group, an acid group, or a methyl group, the toner core tends to become anionic, and the binder resin has an amino group or an amide group. The toner core tends to become cationic. In order for the binder resin to have a strong anionic property, the hydroxyl value (measurement method: JIS (Japanese Industrial Standard) K0070-1992) and acid value (measurement method: JIS (Japanese Industrial Standard) K0070-1992)) of the binder resin are required. Is preferably 10 mgKOH / g or more, more preferably 20 mgKOH / g or more.

  In order to improve toner fixability during high-speed fixing, the softening point (Tm) of the binder resin is preferably 100 ° C. or less, and more preferably 95 ° C. or less. In addition, the measuring method of a softening point (Tm) is the same method as the Example mentioned later, or its alternative method. By combining a plurality of types of resins having different Tm, the Tm of the binder resin can be adjusted.

  The toner according to the exemplary embodiment has the basic configuration described above. The toner core contains, as a binder resin, an amorphous polyester resin and particulate crystalline polyester resin dispersed in the amorphous polyester resin. The toner core may contain a resin other than a polyester resin (more specifically, the above-described various thermoplastic resins) as a binder resin.

  In order for the toner to have the basic structure described above, the non-crystalline polyester resin in the basic structure may be one or more bisphenols (more specifically, polyoxyethylene bisphenol A ether, polyoxypropylene bisphenol A ether, etc. ) And one or more diols (more specifically, terephthalic acid, fumaric acid, alkyl succinic acid, etc.). In order for the toner to have the above-described basic configuration, the crystalline polyester resin in the basic configuration includes at least one divalent carboxylic acid (more specifically, suberic acid, adipic acid, or succinic acid) and one type. It is preferably a polymer with the above diols (more specifically, ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, etc.). The crystalline polyester resin may incorporate one or more repeating units derived from a styrene monomer and one or more repeating units derived from an acrylic acid monomer. One or more repeating units derived from bisphenols (more specifically, polyoxyethylene bisphenol A ether or polyoxypropylene bisphenol A ether) may be incorporated into the crystalline polyester resin.

  In order to achieve both the heat-resistant storage stability and the low-temperature fixability of the toner, it is preferable that the toner core contains one type of crystalline polyester resin and a plurality of types of amorphous polyester resins that are melt-kneaded.

(Coloring agent)
The toner core may contain a colorant. As the colorant, a known pigment or dye can be used according to the color of the toner. In order to form a high-quality image using toner, the amount of the colorant used is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin.

  The toner core may contain a black colorant. An example of a black colorant is carbon black. The black colorant may be a colorant that is toned to black using a yellow colorant, a magenta colorant, and a cyan colorant.

  The toner core may contain a color colorant such as a yellow colorant, a magenta colorant, or a cyan colorant.

  As the yellow colorant, for example, one or more compounds selected from the group consisting of condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, and arylamide compounds can be used. Examples of the yellow colorant include C.I. I. Pigment Yellow (3, 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155 168, 174, 175, 176, 180, 181, 191, or 194), naphthol yellow S, Hansa yellow G, or C.I. I. Vat yellow can be preferably used.

  The magenta colorant is, for example, selected from the group consisting of condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. One or more compounds can be used. Examples of the magenta colorant include C.I. I. Pigment Red (2, 3, 5, 6, 7, 19, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 150, 166, 169, 177 184, 185, 202, 206, 220, 221 or 254) can be preferably used.

  As the cyan colorant, for example, one or more compounds selected from the group consisting of a copper phthalocyanine compound, an anthraquinone compound, and a basic dye lake compound can be used. Examples of cyan colorants include C.I. I. Pigment blue (1, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 60, 62, or 66), phthalocyanine blue, C.I. I. Bat Blue, or C.I. I. Acid blue can be preferably used.

(Release agent)
The toner core may contain a release agent. The release agent is used, for example, for the purpose of improving the fixing property or offset resistance of the toner. In order to increase the anionicity of the toner core, it is preferable to produce the toner core using an anionic wax. In order to improve the fixing property or offset resistance of the toner, the amount of the release agent used is preferably 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the binder resin.

  Examples of the release agent include low molecular weight polyethylene, low molecular weight polypropylene, polyolefin copolymer, polyolefin wax, microcrystalline wax, paraffin wax, or aliphatic hydrocarbon wax such as Fischer-Tropsch wax; oxidized polyethylene wax or a block thereof Oxides of aliphatic hydrocarbon waxes such as copolymers; plant waxes such as candelilla wax, carnauba wax, wood wax, jojoba wax, or rice wax; animal properties such as beeswax, lanolin, or whale wax Waxes; mineral waxes such as ozokerite, ceresin, or petrolatum; waxes based on fatty acid esters such as montanate ester wax or castor wax; fats such as deoxidized carnauba wax The wax portion of the ester or the whole was deoxygenated can be suitably used. One type of release agent may be used alone, or multiple types of release agents may be used in combination.

  In order to improve the compatibility between the binder resin and the release agent, a compatibilizer may be added to the toner core.

(Charge control agent)
The toner core may contain a charge control agent. The charge control agent is used, for example, for the purpose of improving the charge stability or charge rising property of the toner. The charge rising characteristic of the toner is an index as to whether or not the toner can be charged to a predetermined charge level in a short time.

  By adding a negatively chargeable charge control agent to the toner core, the anionicity of the toner core can be enhanced. Further, the cationic property of the toner core can be increased by including a positively chargeable charge control agent in the toner core. However, if sufficient chargeability is ensured in the toner, it is not necessary to include a charge control agent in the toner core.

(Magnetic powder)
The toner core may contain magnetic powder. Examples of the magnetic powder include iron (more specifically, ferrite or magnetite), ferromagnetic metal (more specifically, cobalt or nickel), an alloy containing iron and / or ferromagnetic metal, strong A ferromagnetic alloy or chromium dioxide that has been magnetized (more specifically, heat treatment or the like) can be suitably used. One type of magnetic powder may be used alone, or a plurality of types of magnetic powder may be used in combination.

  In order to suppress elution of metal ions (for example, iron ions) from the magnetic powder, it is preferable to surface-treat the magnetic powder. When a shell layer is formed on the surface of the toner core under acidic conditions, if the metal ions are eluted on the surface of the toner core, the toner cores are easily fixed to each other. It is considered that fixing of the toner cores can be suppressed by suppressing elution of metal ions from the magnetic powder.

[Shell layer]
The shell layer may be a film without graininess or a film with graininess. When resin particles are used as a material for forming the shell layer, if the material (resin particles) is completely melted and cured in a film-like form, it is considered that a film without graininess is formed as the shell layer. It is done. On the other hand, if the material (resin particles) is not completely melted and cured in a film form, a film having a form in which the resin particles are two-dimensionally connected (a film having a granular feeling) is formed as a shell layer. it is conceivable that.

  The shell layer may consist essentially of a thermosetting resin, may consist essentially of a thermoplastic resin, or may contain both a thermosetting resin and a thermoplastic resin. Good. When the shell layer contains both a thermosetting resin and a thermoplastic resin, the ratio of the thermoplastic resin and the thermosetting resin in the shell layer is arbitrary. Examples of the ratio of thermoplastic resin to thermosetting resin include 1: 1, 1: 2, 1: 3, 1: 4, 1: 5, 2: 1, 3: 1, 4: 1, or 5 : 1 (each in a mass ratio, thermoplastic resin: thermosetting resin).

  In order to improve the heat resistant storage stability of the toner, the shell layer preferably contains the above-described suitable thermosetting resin. In order to improve the charging stability and heat resistant storage stability of the toner, the shell layer should contain one or more thermosetting resins selected from the group consisting of melamine resins, urea resins, and glyoxal resins. Is particularly preferred.

  In order to improve the charging stability of the toner, the shell layer preferably contains a hydrophobic resin. As the hydrophobic resin to be contained in the shell layer, a thermoplastic resin (more specifically, the above-described suitable thermoplastic resin or the like), or a thermosetting resin obtained by crosslinking the above-described suitable thermoplastic resin with a crosslinking agent. Preferably, a resin (thermosetting) in which at least one styrene monomer (for example, styrene monomer) and at least one acrylic acid monomer (for example, acrylate monomer) are crosslinked by a crosslinking agent (for example, divinylbenzene). Resin) is particularly preferred. Styrene-acrylic acid resins are more hydrophobic than polyester resins and tend to be positively charged. In order to improve the film quality of the shell layer, the resin (crosslinked resin) contained in the shell layer is 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, or It preferably has one or more alcoholic hydroxyl groups derived from 2-hydroxypropyl methacrylate.

  In order to improve the charging stability of the toner, the shell layer preferably contains a charging resin (a resin containing a charge control agent) in addition to the hydrophobic resin. As the chargeable resin to be contained in the shell layer, a thermoplastic resin incorporating a repeating unit derived from a positively chargeable charge control agent (more specifically, the above-described preferred thermoplastic resin or the like) is preferable. A copolymer of the above quaternary ammonium compound (eg, quaternary ammonium salt) monomer and one or more acrylic acid monomers (eg, acrylate monomer) is particularly preferred. Preferred examples of the positively chargeable charge control agent used for the synthesis of the chargeable resin are shown below. In addition, you may use the derivative | guide_body or salt of each compound shown below as needed.

  Examples of the positively chargeable charge control agent include pyridazine, pyrimidine, pyrazine, 1,2-oxazine, 1,3-oxazine, 1,4-oxazine, 1,2-thiazine, 1,3-thiazine, 1, 4-thiazine, 1,2,3-triazine, 1,2,4-triazine, 1,3,5-triazine, 1,2,4-oxadiazine, 1,3,4-oxadiazine, 1,2,6- Oxadiazine, 1,3,4-thiadiazine, 1,3,5-thiadiazine, 1,2,3,4-tetrazine, 1,2,4,5-tetrazine, 1,2,3,5-tetrazine, 1, Azine compounds such as 2,4,6-oxatriazine, 1,3,4,5-oxatriazine, phthalazine, quinazoline or quinoxaline; Azin Fast Red FC, Azin Fast Red 12BK, A Direct dyes such as violet BO, azine brown 3G, azine light brown GR, azine dark green BH / C, azine dip black EW, or azine black 3RL; nigrosine compounds (more specifically, nigrosine BK , Nigrosine NB, or nigrosine Z); metal salts of naphthenic acid or higher organic carboxylic acids; alkoxylated amines; alkylamides; benzyldecylhexylmethylammonium chloride, decyltrimethylammonium chloride, or 2- (methacryloyl) Quaternary ammonium salts such as oxy) ethyltrimethylammonium chloride can be preferably used.

[External additive]
An external additive may be attached to the surface of the toner base particles. The external additive is used, for example, to improve the fluidity or handleability of the toner. In order to improve the fluidity or handleability of the toner, the amount of the external additive used is preferably 0.5 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the toner base particles. In order to improve the fluidity or handleability of the toner, the particle diameter of the external additive is preferably 0.01 μm or more and 1.0 μm or less.

  As the external additive, particles of silica particles or metal oxides (more specifically, alumina, titanium oxide, magnesium oxide, zinc oxide, strontium titanate, barium titanate, etc.) can be preferably used. One type of external additive may be used alone, or a plurality of types of external additives may be used in combination.

[Toner Production Method]
Hereinafter, an example of a method for producing the toner having the above configuration will be described.

The method for producing a toner for developing an electrostatic latent image according to this embodiment includes the following preferred production steps (melt kneading of the toner core material, grinding of the kneaded material, addition of the material, and formation of the shell layer).
(Suitable manufacturing process)
In the melt kneading of the toner core material (material for forming the toner core), the toner core material containing at least the non-crystalline polyester resin and the crystalline polyester resin is melt kneaded to produce a crystal whose dispersion diameter is not in the range of 40 nm to 150 nm. A kneaded product containing a conductive polyester resin is obtained. In the pulverization of the kneaded product, the toner core is obtained by pulverizing the kneaded product. In the addition of the material, a toner core and a shell material (shell layer material) are placed in an aqueous medium. In the formation of the shell layer, the shell material is polymerized in an aqueous medium so that the dispersion diameter of the crystalline polyester resin in the toner core is 40 nm or more and 150 nm or less, and the shell layer is formed on the surface of the toner core.

  The method including the above preferred production process is useful for easily and suitably producing the toner having the above-described basic configuration. Hereinafter, based on a more specific example, the method including the preferred manufacturing process will be further described. In this example, the toner core has an anionic property, and the shell material (and thus the shell layer) has a cationic property. When the toner core is anionic and the shell material is cationic, the shell material that is positively charged in the liquid is electrically attracted to the toner core that is negatively charged in the liquid. By pulling the shell material to the toner core in the liquid, it becomes possible to form a shell layer on the surface of the toner core by in-situ polymerization.

(Preparation of toner core)
In order to easily obtain the toner having the above-described basic configuration, it is particularly preferable to manufacture the toner core by a pulverization method.

  Hereinafter, an example of the pulverization method will be described. First, at least one of a binder resin (for example, a plurality of types of non-crystalline polyester resins and a single type of crystalline polyester resin) and an internal additive (for example, a colorant, a release agent, a charge control agent, and magnetic powder). One). Subsequently, the obtained mixture is melt-kneaded to obtain a kneaded product containing a crystalline polyester resin having a dispersion diameter not in the range of 40 nm to 150 nm. Subsequently, the obtained kneaded product is pulverized and classified. As a result, a toner core having a desired particle size can be obtained.

(Formation of shell layer)
For example, ion exchange water is prepared as an aqueous medium. Subsequently, the pH of the aqueous medium is adjusted to a predetermined pH (hereinafter referred to as shell material polymerization pH) using, for example, hydrochloric acid. In order to promote the formation of the shell layer, the shell material polymerization pH is preferably 3 or more and 5 or less (weakly acidic).

  Subsequently, a toner core and a suspension of a hydrophobic resin (a liquid containing hydrophobic resin particles) are added to a liquid whose pH is adjusted (for example, acidic ion-exchanged water). As the hydrophobic resin, for example, a resin in which one or more styrene monomers and one or more acrylic monomers are crosslinked with a crosslinking agent (for example, divinylbenzene) can be used. In order to improve the film quality of the shell layer, the number average particle diameter of the hydrophobic resin particles is preferably 20 nm or more and 50 nm or less. When the toner core has an anionic property, aggregation of the toner core can be suppressed by using an anionic surfactant having the same polarity. As the anionic surfactant, for example, a sulfate ester surfactant, a sulfonate surfactant, a phosphate ester surfactant, or a soap can be used. Moreover, you may add the material for synthesize | combining a chargeable resin and / or a thermosetting resin in a liquid as needed.

  The shell material and the like may be added to an aqueous medium at room temperature. However, the molecular weight of the shell layer can be controlled by controlling the temperature of the aqueous medium. The appropriate addition amount of the shell material can be calculated based on the specific surface area of the toner core. In addition to the shell material and the like, a polymerization accelerator may be added to the aqueous medium.

  In order to uniformly adhere the shell material to the surface of the toner core, it is preferable to highly disperse the toner core in a liquid containing the shell material. In order to highly disperse the toner core in the liquid, a dispersant may be included in the liquid, or the liquid is stirred using a powerful stirring device (for example, “Hibis Disper Mix” manufactured by Primics Co., Ltd.). Also good.

  Subsequently, while stirring the liquid containing the shell material and the like, the liquid temperature is set at a predetermined speed (for example, a speed selected from 0.1 ° C./min to 3 ° C./min) at a predetermined shell material polymerization temperature (for example, And a temperature selected from 50 ° C. to 85 ° C.). Furthermore, the temperature of the liquid is maintained at the shell material polymerization temperature for a predetermined time (for example, a time selected from 30 minutes to 4 hours) while stirring the liquid. While the temperature of the liquid is kept high, the dispersion diameter of the crystalline polyester resin in the toner core becomes 40 nm or more and 150 nm or less, and the shell material adheres to the surface of the toner core. Further, the shell material undergoes a polymerization reaction on the surface of the toner core, so that a shell layer substantially composed of a resin is formed on the surface of the toner core. It is considered that the particulate hydrophobic resin is dissolved in the liquid and cured in a film-like form.

  In order to suppress elution of the toner core component or deformation of the toner core, the shell material polymerization temperature (the temperature of the liquid during shell layer curing) is preferably less than the glass transition point (Tg) of the toner core. However, the toner core may be intentionally deformed by setting the shell material polymerization temperature to be equal to or higher than the glass transition point (Tg) of the toner core. When the shell material polymerization temperature is increased, the deformation of the toner core is promoted, and the shape of the toner base particles tends to approach a true sphere. It is desirable to adjust the shell material polymerization temperature so that the toner base particles have a desired shape. Further, when the shell material is reacted at a high temperature, the shell layer tends to become hard. The molecular weight of the shell layer can also be controlled based on the shell material polymerization temperature.

  After the shell layer is cured as described above, the dispersion of toner base particles is neutralized using, for example, sodium hydroxide. Subsequently, the toner mother particle dispersion is cooled to, for example, room temperature (about 25 ° C.). Subsequently, the dispersion of the toner base particles is filtered using, for example, a Buchner funnel. Thereby, the toner base particles are separated from the liquid (solid-liquid separation), and wet cake-like toner base particles are obtained. Subsequently, the obtained wet cake-like toner base particles are washed. Subsequently, the washed toner base particles are dried. Thereafter, if necessary, the toner base particles and the external additive are mixed using a mixer (for example, FM mixer manufactured by Nippon Coke Kogyo Co., Ltd.), and the external additive is adhered to the surface of the toner base particles. May be. When a spray dryer is used in the drying step, the drying step and the external addition step can be performed at the same time by spraying a dispersion of an external additive (for example, silica particles) onto the toner base particles. Thus, a toner containing a large number of toner particles is manufactured.

  The contents and order of the toner manufacturing method can be arbitrarily changed according to the required configuration or characteristics of the toner. For example, the timing of adjusting the pH of the liquid (for example, an aqueous medium) may be before or after the aforementioned shell material or the like (shell material and toner core) is added to the liquid. The shell material or the like may be added simultaneously at the same time, or may be added separately. Moreover, you may make it perform the process of heating a liquid to shell material polymerization temperature before the process of adding shell material etc. to a liquid. In addition, when reacting a material (for example, a shell material) in the liquid, the material may be reacted in the liquid for a predetermined time after the material is added to the liquid, or the material is added to the liquid over a long period of time. Then, the material may be reacted in the liquid while adding the material to the liquid. Further, the shell material may be added to the liquid at once, or may be added to the liquid in a plurality of times. The method for forming the shell layer is arbitrary. For example, the shell layer may be formed using any of an in-situ polymerization method, a submerged cured coating method, and a coacervation method. Further, the toner may be sieved after the external addition step. Further, unnecessary steps may be omitted. For example, when a commercially available product can be used as a material as it is, the step of preparing the material can be omitted by using a commercially available product. Further, when the polymerization reaction of the shell material proceeds satisfactorily without adjusting the pH of the liquid, the pH adjustment step may be omitted. If an external additive is unnecessary, the external addition process may be omitted. When the external additive is not attached to the surface of the toner base particles (the step of external addition is omitted), the toner base particles correspond to the toner particles. The toner core material and the shell material are not limited to the aforementioned compounds (monomers for synthesizing the resin, etc.). For example, if necessary, a derivative or salt of the aforementioned compound may be used as the toner core material or shell material, or a prepolymer may be used instead of the monomer. Further, in order to obtain the above-mentioned compound, a salt, ester, hydrate, or anhydride of the compound may be used as a raw material. Various materials may be used in a solid state or in a liquid state. For example, a powder of a solid state material may be used, a solution of the material (a liquid state material dissolved in a solvent) may be used, or a dispersion of the material (a liquid in which the solid state material is dispersed) ) May be used. In order to produce the toner efficiently, it is preferable to form a large number of toner particles simultaneously.

  Examples of the present invention will be described. Table 1 shows toners A-1 to A-9, B-1, B-2, C-1, C-2, and D-1 to D-3 according to Examples or Comparative Examples (electrostatic latent images, respectively). Developing toner).

Hereinafter, a manufacturing method, an evaluation method, and an evaluation result of toners A-1 to D-3 will be described in order. It should be noted that the evaluation results (values indicating the shape, physical properties, etc.) regarding the powder containing a plurality of particles (more specifically, toner base particles, external additives, toners, etc.) It is the number average of the values measured for a number of particles. In the evaluation in which an error occurs, a considerable number of measurement values with which the error is sufficiently small are obtained, and the arithmetic average of the obtained measurement values is used as the evaluation value. Further, the particle diameter of the powder is a circle equivalent diameter of a particle (a diameter of a circle having the same area as the projected area of the particle) unless otherwise specified. Moreover, the measured value of the volume median diameter (D ₅₀ ) is a value measured using “Coulter Counter Multisizer 3” manufactured by Beckman Coulter Co., Ltd. unless otherwise specified. In addition, methods for measuring Tg (glass transition point), Mp (melting point), and Tm (softening point) are as follows unless otherwise specified.

<Measurement method of Tg and Mp>
As a measuring device, a differential scanning calorimeter (“DSC-6220” manufactured by Seiko Instruments Inc.) was used. The Tg and Mp of the sample were determined by measuring the endothermic curve of the sample (for example, polyester resin) using a measuring device. Specifically, 15 mg of a sample (for example, polyester resin) was placed in an aluminum dish, and the aluminum dish was set in the measurement unit of the measurement apparatus. In addition, an empty aluminum dish was used as a reference. In the measurement of the endothermic curve, the temperature of the measurement part was increased from the measurement start temperature of 10 ° C. to 150 ° C. at a rate of 10 ° C./min (RUN1). Thereafter, the temperature of the measurement part was lowered from 150 ° C. to 10 ° C. at a rate of 10 ° C./min. Subsequently, the temperature of the measurement part was again increased from 10 ° C. to 150 ° C. at a rate of 10 ° C./min (RUN 2). An endothermic curve (vertical axis: heat flow (DSC signal), horizontal axis: temperature) of the sample was obtained by RUN2. The Mp and Tg of the sample were read from the obtained endothermic curve. In the endothermic curve, the maximum peak temperature due to the heat of fusion corresponds to the Mp (melting point) of the sample. In the endothermic curve, the temperature (onset temperature) of the specific heat change point (intersection of the extrapolation line of the base line and the extrapolation line of the falling line) corresponds to the Tg (glass transition point) of the sample.

<Tm measurement method>
A sample (for example, polyester resin) is set on a Koka type flow tester (“CFT-500D” manufactured by Shimadzu Corporation), a die pore diameter of 1 mm, a plunger load of 20 kg / cm ² , and a heating rate of 6 ° C./min. Under the conditions, a 1 cm ³ sample was melted and discharged, and an S-shaped curve (horizontal axis: temperature, vertical axis: stroke) of the sample was obtained. Subsequently, the Tm of the sample was read from the obtained S-shaped curve. In the S-curve, if the maximum stroke value is S ₁ and the low-temperature baseline stroke value is S ₂ , the temperature at which the stroke value in the S-curve is “(S ₁ + S ₂ ) / 2” Corresponds to the Tm (softening point) of the sample.

  Further, for each of the toners A-1 to D-3, the crystalline-noncrystalline SP value difference ("SP value difference" in Table 1) was calculated by the Collman method described above. Further, for each of the toners A-1 to D-3, the dispersion diameter of the crystalline polyester resin in the toner core (“dispersion diameter” in Table 1) is measured using a scanning probe microscope (SPM) by the following method. Crystalline-amorphous phase difference (“phase difference” in Table 1) was measured.

<Measurement method by SPM>
A sample (toner) was coated with gold by sputtering and then embedded with a visible light curable resin to obtain a cured product. Thereafter, a knife for preparing an ultrathin section (“Sumiknife (registered trademark)” manufactured by Sumitomo Electric Industries, Ltd .: a diamond knife having a blade width of 2 mm and a blade tip angle of 45 °) and an ultramicrotome (“EM UC6” manufactured by Leica Microsystems) By cutting the cured product with a cutting speed of 0.3 mm / sec, a thin piece of 150 nm was produced. Subsequently, the obtained flakes were set on an SPM probe station (“NanoNaviReal” manufactured by Hitachi High-Tech Science Co., Ltd.) equipped with a scanning probe microscope (“Multifunctional Unit AFM5200S” manufactured by Hitachi High-Tech Science Co., Ltd.). The phase signal and phase image were measured under the following conditions.
(SPM measurement conditions)
Measurement probe: low spring constant silicon cantilever ("OMCL-AC240TS-C3" manufactured by Olympus Corporation, spring constant: 2 N / m, resonance frequency: 70 kHz, back reflection coating material: aluminum)
Measurement mode: SIS-DFM (SIS: sampling intelligent scan, DFM: dynamic force mode)
・ Measurement range: 500nm x 500nm
・ Resolution (X data / Y data): 512/512

  In the state where the cantilever (tip: probe) is resonated by the measurement mode (SIS-DFM), the phase is controlled while controlling the distance between the probe and the sample so that the amplitude of the vibrating cantilever is constant. Signal and phase images were obtained. In the obtained phase image, there were many domains (domains showing particles) having a clearly larger phase lag than the surrounding portion. 20 of these domains were arbitrarily selected, and the particle diameter (longest diameter) was measured for each of the 20 selected domains. The arithmetic average value of the 20 measured values (longest diameter) obtained was used as the evaluation value (dispersion diameter of the crystalline polyester resin in the toner core) of the sample (toner).

  Further, based on the phase signal obtained as described above, a phase delay histogram (for example, see FIG. 1) was obtained. From the obtained histogram, with respect to the crystalline polyester resin and the amorphous polyester resin contained in the sample (toner), the peak phase lag value (unit: degree) derived from the crystalline polyester resin is determined to be amorphous. The evaluation value (crystallinity-amorphous phase difference) of the sample (toner) was determined by subtracting the peak phase lag value (unit: degree) derived from the crystalline polyester resin.

[Method for Producing Toner A-1]
(Synthesis of crystalline polyester resin A)
In a 10 L four-necked flask equipped with a thermometer (thermocouple), dehydration tube, nitrogen introduction tube, and stirring device, 2231 g of ethylene glycol, 5869 g of suberic acid, and 40 g of tin (II) 2-ethylhexanoate And 3 g of gallic acid. Subsequently, the contents of the flask were reacted for 4 hours under conditions of a nitrogen atmosphere and a temperature of 180 ° C. Subsequently, the contents of the flask were heated and reacted at a temperature of 210 ° C. for 10 hours. Subsequently, the contents of the flask were reacted for 1 hour in a reduced pressure atmosphere (pressure 8.3 kPa) and a temperature of 210 ° C. As a result, a crystalline polyester resin A having a Tm of 88 ° C., an Mp of 84 ° C., a crystallinity index of 1.05, and an SP value of 11.8 J / cm ³ was obtained.

(Synthesis of non-crystalline polyester resin A)
In a 10 L four-necked flask equipped with a thermometer (thermocouple), dehydration tube, nitrogen introduction tube, and stirrer, 370 g of polyoxypropylene bisphenol A ether, 3059 g of polyoxyethylene bisphenol A ether, terephthalic acid 1194 g, 286 g of fumaric acid, 10 g of tin (II) 2-ethylhexanoate, and 2 g of gallic acid were added. Subsequently, the contents of the flask were reacted in a nitrogen atmosphere and at a temperature of 230 ° C. until the reaction rate reached 90% by mass or more. The reaction rate was calculated according to the formula “reaction rate = 100 × actual amount of reaction product water / theoretical product water amount”. Subsequently, the flask contents were reacted in a reduced-pressure atmosphere (pressure 8.3 kPa) until the Tm of the reaction product (resin) reached a predetermined temperature (89 ° C.). As a result, an amorphous polyester resin A having a Tm of 89 ° C., a Tg of 50 ° C., and an SP value of 11.2 J / cm ³ was obtained.

(Synthesis of non-crystalline polyester resin B)
The method for synthesizing the non-crystalline polyester resin B is 370 g of polyoxypropylene bisphenol A ether, 3059 g of polyoxyethylene bisphenol A ether, 1194 g of terephthalic acid, and 286 g of fumaric acid, 1286 g of polyoxypropylene bisphenol A ether, polyoxyethylene The method was the same as the method for synthesizing the amorphous polyester resin A except that 2218 g of bisphenol A ether and 1603 g of terephthalic acid were used. Regarding amorphous polyester resin B, Tm was 111 ° C., Tg was 69 ° C., and SP value was 10.4 J / cm ³ .

(Synthesis of non-crystalline polyester resin C)
In a 10 L four-necked flask equipped with a thermometer (thermocouple), dehydration tube, nitrogen inlet tube, and stirring device, 4907 g of polyoxypropylene bisphenol A ether, 1942 g of polyoxyethylene bisphenol A ether, fumaric acid 757 g, 2078 g of dodecyl succinic anhydride, 30 g of tin (II) 2-ethylhexanoate, and 2 g of gallic acid were added. Subsequently, the contents of the flask were reacted in a nitrogen atmosphere and at a temperature of 230 ° C. until the reaction rate represented by the above formula reached 90% by mass or more. Subsequently, the flask contents were reacted for 1 hour in a reduced-pressure atmosphere (pressure 8.3 kPa). Subsequently, 548 g of trimetic anhydride is added to the flask, and the reaction product (resin) has a Tm of a predetermined temperature (127 ° C.) under a reduced pressure atmosphere (pressure 8.3 kPa) and a temperature of 220 ° C. The contents of the flask were allowed to react. As a result, an amorphous polyester resin C having a Tm of 127 ° C., a Tg of 51 ° C., and an SP value of 10.7 J / cm ³ was obtained.

(Production of toner core)
Using an FM mixer ("FM-20B" manufactured by Nippon Coke Industries Co., Ltd.), 100 g of the first binder resin (crystalline polyester resin A synthesized by the above procedure) and the second binder resin (by the above procedure). 300 g of the synthesized amorphous polyester resin A), 100 g of the third binder resin (amorphous polyester resin B synthesized by the above procedure), and the fourth binder resin (amorphous polyester synthesized by the above procedure) Resin C) 600 g, 144 g of a colorant (“Colorex (registered trademark) Blue B1021” manufactured by Sanyo Pigment Co., Ltd., component: phthalocyanine blue), and a first release agent (“Carnauba Wax 1 manufactured by Hiroyuki Kato Co., Ltd.) No. ", component: carnauba wax) and second release agent (" Nissan Electol (registered trademark) WEP-3 "manufactured by NOF Corporation, component: ester wax) And 8 g, was mixed at a rotation speed 2400 rpm. In the toner A-1, the SP value (SP _A ) of the amorphous polyester resin is 10.8 J / cm ³ (= 11.2 J / cm ³ × 0.3 + 10.4 J / cm ³ × 0.1 + 10.7 J / cm). ³ × 0.6), and the SP value (SP _B ) of the crystalline polyester resin was 11.8 J / cm ³ .

Subsequently, the obtained mixture was subjected to conditions using a twin-screw extruder (“PCM-30” manufactured by Ikegai Co., Ltd.) at a material supply speed of 5 kg / hour, a shaft rotation speed of 160 rpm, and a set temperature (cylinder temperature) of 100 ° C. Was melt kneaded. Thereafter, the obtained kneaded material was cooled. Subsequently, the cooled kneaded material was coarsely pulverized using a pulverizer (“Rotoplex (registered trademark) 16/8 type” manufactured by Hosokawa Micron Corporation). Subsequently, the obtained coarsely pulverized product was finely pulverized using a jet mill (“Ultrasonic Jet Mill Type I” manufactured by Nippon Pneumatic Industry Co., Ltd.). Subsequently, the obtained finely pulverized product was classified using a classifier (“Elbow Jet EJ-LABO type” manufactured by Nippon Steel Mining Co., Ltd.). As a result, toner mother particles having a volume median diameter (D ₅₀ ) of 6 μm were obtained.

(Preparation of shell material)
A 1 L three-necked flask equipped with a thermometer and a stirring blade was set in a water bath, and 875 mL of ion-exchanged water and an anionic surfactant (“Latemul (registered trademark) WX” manufactured by Kao Corporation, components: 75 mL of polyoxyethylene alkyl ether sodium sulfate, solid content concentration: 26% by mass). Thereafter, the temperature in the flask was raised to 80 ° C. using a water bath, and then kept at that temperature (80 ° C.). Subsequently, two kinds of liquids (first liquid and second liquid) were dropped into the flask contents at 80 ° C. over 5 hours, respectively. The first liquid was a mixed liquid of 12 mL of styrene, 4 mL of 2-hydroxyethyl methacrylate (HEMA), 4 mL of butyl acrylate, and 0.5 mL of divinylbenzene. The second liquid was a solution in which 0.5 g of potassium persulfate was dissolved in 30 mL of ion exchange water. Subsequently, the temperature in the flask was kept at 80 ° C. for another 2 hours to polymerize the flask contents. As a result, a suspension of resin fine particles (hydrophobic resin) (hereinafter referred to as suspension A) was obtained. The resin fine particles contained in the obtained suspension A had a number average particle diameter of 39 nm and a glass transition point (Tg) of 73 ° C.

(Shell layer forming process)
A 1 L three-necked flask equipped with a thermometer and a stirring blade was set in a water bath, and 300 mL of ion-exchanged water was placed in the flask. Thereafter, the temperature in the flask was kept at 30 ° C. using a water bath. Subsequently, dilute hydrochloric acid was added to the flask to adjust the pH of the flask contents (shell material polymerization pH) to 4. Subsequently, 15 mL of shell material (Suspension A prepared by the above procedure) was added to the flask to obtain an aqueous solution of shell material. Subsequently, 300 g of a toner core (toner core produced by the above procedure) was added to the flask, and the flask contents were stirred for 1 hour at a rotation speed of 200 rpm. Subsequently, 300 mL of ion exchange water was added to the flask.

  Subsequently, while stirring the flask contents at a rotation speed of 100 rpm, the temperature in the flask was increased to 70 ° C. (predetermined shell material polymerization temperature) at a rate of 1 ° C./min. Subsequently, the flask contents were stirred for 2 hours under the conditions of a temperature of 70 ° C. (shell material polymerization temperature) and a rotation speed of 100 rpm.

  Subsequently, sodium hydroxide was added to the flask to adjust the pH of the flask contents to 7. Subsequently, the flask contents were cooled until the temperature reached room temperature (about 25 ° C.) to obtain a dispersion liquid containing toner mother particles.

(Washing process)
The dispersion of toner base particles obtained as described above was filtered (solid-liquid separation) using a Buchner funnel to obtain wet cake-like toner base particles. Thereafter, the obtained wet cake-like toner base particles were redispersed in ion-exchanged water. Further, dispersion and filtration were repeated 5 times to wash the toner base particles.

(Drying process)
Subsequently, the obtained toner base particles were dispersed in an aqueous ethanol solution having a concentration of 50% by mass. As a result, a slurry of toner base particles was obtained. Subsequently, the toner base particles in the slurry were removed under the conditions of a hot air temperature of 45 ° C. and a blower air volume of 2 m ³ / min using a continuous surface reformer (“Coat Mizer (registered trademark)” manufactured by Freund Sangyo Co., Ltd.). Dried. As a result, toner mother particle powder was obtained. As a result of observing the dried toner base particles using a scanning electron microscope (SEM), a granular feeling was observed in the shell layer, but the particles constituting the shell layer were not separated.

(External addition process)
Using an FM mixer with a capacity of 10 L (“FM-10B” manufactured by Nippon Coke Industries, Ltd.), 1 part by mass of toner base particles and dry silica particles (“AEROSIL (registered trademark) REA90” manufactured by Nippon Aerosil Co., Ltd.) Part and 0.5 parts by mass of conductive titanium oxide fine particles (“EC-100” manufactured by Titanium Industry Co., Ltd.) were mixed for 5 minutes. As a result, the external additive adhered to the surface of the toner base particles. Thereafter, sieving was performed using a 200 mesh sieve (aperture 75 μm). As a result, Toner A-1 containing a large number of toner particles was obtained. With respect to the obtained toner A-1, the dispersion diameter of the crystalline polyester resin in the toner core was 44 nm, the crystalline-noncrystalline phase difference was -13 °, and the crystalline-noncrystalline SP difference was 1.0. (See Table 1).

[Production Method of Toner A-2]
The production method of the toner A-2 was the same as the production method of the toner A-1, except that the crystalline polyester resin B synthesized by the following method was used instead of the crystalline polyester resin A.
(Synthesis of crystalline polyester resin B)
The method for synthesizing the crystalline polyester resin B was the same as the method for synthesizing the crystalline polyester resin A, except that 2735 g of 1,2-propanediol and 4922 g of adipic acid were used instead of 2231 g of ethylene glycol and 5869 g of suberic acid. It was. Regarding the obtained crystalline polyester resin B, Tm was 90 ° C., Mp was 84 ° C., the crystallinity index was 1.07, and the SP value was 11.5 J / cm ³ .

[Method for Producing Toner A-3]
The production method of the toner A-3 was the same as the production method of the toner A-1, except that the crystalline polyester resin C synthesized by the following method was used instead of the crystalline polyester resin A.
(Synthesis of crystalline polyester resin C)
The method for synthesizing the crystalline polyester resin C was the same as the method for synthesizing the crystalline polyester resin A except that 3744 g of 1,5-pentanediol was used instead of 2231 g of ethylene glycol. With respect to the obtained crystalline polyester resin C, Tm was 86 ° C., Mp was 79 ° C., the crystallinity index was 1.09, and the SP value was 11.9 J / cm ³ .

[Method for Producing Toner A-4]
The production method of the toner A-4 was the same as the production method of the toner A-1, except that the crystalline polyester resin D synthesized by the following method was used instead of the crystalline polyester resin A.
(Synthesis of crystalline polyester resin D)
The method for synthesizing the crystalline polyester resin D was the same as the method for synthesizing the crystalline polyester resin A except that 3978 g of succinic acid was used instead of 5869 g of suberic acid. With respect to the obtained crystalline polyester resin D, Tm was 104 ° C., Mp was 102 ° C., the crystallinity index was 1.02, and the SP value was 11.1 J / cm ³ .

[Production Method of Toner A-5]
The production method of the toner A-5 was the same as the production method of the toner A-1, except that the crystalline polyester resin E synthesized by the following method was used instead of the crystalline polyester resin A.
(Synthesis of crystalline polyester resin E)
The method for synthesizing the crystalline polyester resin E is the synthesis of the crystalline polyester resin A except that ethylene glycol 2008 g, polyoxyethylene bisphenol A ether 1136 g, and succinic acid 3978 g are used instead of ethylene glycol 2231 g and suberic acid 5869 g. It was the same as the method. With respect to the obtained crystalline polyester resin E, Tm was 87 ° C., Mp was 92 ° C., the crystallinity index was 0.94, and the SP value was 10.9 J / cm ³ .

[Production Method of Toner A-6]
The production method of the toner A-6 was the same as the production method of the toner A-1, except that the crystalline polyester resin F synthesized by the following method was used instead of the crystalline polyester resin A.
(Synthesis of crystalline polyester resin F)
2232 g of ethylene glycol and 5515 g of suberic acid were placed in a 10 L four-necked flask equipped with a thermometer (thermocouple), dehydration tube, nitrogen introduction tube, and stirring device. Subsequently, the flask contents were heated to a temperature of 160 ° C. to dissolve the added material. Subsequently, using a dropping funnel, a mixed liquid of styrene or the like (a mixed liquid of 488 g of styrene, 52 g of acrylic acid, and 29 g of dicumyl peroxide) was dropped into the flask over 1 hour. Subsequently, the contents of the flask were reacted at a temperature of 170 ° C. for 1 hour while stirring to polymerize styrene and acrylic acid in the flask. Then, the unreacted styrene and acrylic acid in the flask were removed by maintaining in a reduced pressure atmosphere (pressure 8.3 kPa) for 1 hour. Subsequently, 40 g of tin (II) 2-ethylhexanoate and 3 g of gallic acid were added to the flask. Subsequently, the flask contents were heated and reacted at a temperature of 210 ° C. for 8 hours. Subsequently, the contents of the flask were reacted for 1 hour in a reduced pressure atmosphere (pressure 8.3 kPa) and a temperature of 210 ° C. As a result, a crystalline polyester resin F having a Tm of 90 ° C., an Mp of 83 ° C., a crystallinity index of 1.09, and an SP value of 10.6 J / cm ³ was obtained.

[Production Method of Toner A-7]
The production method of the toner A-7 was the same as the production method of the toner A-6 except that the crystalline polyester resin G synthesized by the following method was used instead of the crystalline polyester resin F.
(Synthesis of crystalline polyester resin G)
The method of synthesizing the crystalline polyester resin G is as follows. With respect to the amount of each material added, 2232 g of ethylene glycol is 1984 g, 5515 g of suberic acid is 4345 g, 488 g of styrene is 1831 g, 52 g of acrylic acid is 161 g, and dicumyl. The method was the same as the method for synthesizing the crystalline polyester resin F except that 29 g of peroxide was changed to 110 g. Regarding the obtained crystalline polyester resin G, Tm was 90 ° C., Mp was 83 ° C., the crystallinity index was 1.09, and the SP value was 10.3 J / cm ³ .

[Production Method of Toner A-8]
The production method of the toner A-8 was the same as the production method of the toner A-6 except that the crystalline polyester resin H synthesized by the following method was used in place of the crystalline polyester resin F.
(Synthesis of crystalline polyester resin H)
The method for synthesizing the crystalline polyester resin H is the crystalline polyester except that 2974 g of 1,6-hexanediol, 972 g of 1,4-butanediol, and 3739 g of succinic acid are used instead of 2232 g of ethylene glycol and 5515 g of suberic acid. It was the same as the synthetic method of Resin F. Regarding the obtained crystalline polyester resin H, Tm was 92 ° C., Mp was 91 ° C., the crystallinity index was 1.01, and the SP value was 10.4 J / cm ³ .

[Production Method of Toner A-9]
The production method of the toner A-9 was the same as the production method of the toner A-6 except that the crystalline polyester resin I synthesized by the following method was used in place of the crystalline polyester resin F.
(Synthesis of crystalline polyester resin I)
The method for synthesizing crystalline polyester resin I is crystalline polyester except that instead of ethylene glycol 1984 g and suberic acid 4345 g, 1,6-hexanediol 2643 g, 1,4-butanediol 864 g and succinic acid 2945 g were used. The synthesis method of Resin G was the same. Regarding the obtained crystalline polyester resin I, Tm was 92 ° C., Mp was 96 ° C., the crystallinity index was 0.95, and the SP value was 10.0 J / cm ³ .

[Method for Producing Toner B-1]
The production method of the toner B-1 was the same as the production method of the toner A-8, except that the melt kneading temperature (cylinder temperature) was changed from 100 ° C. to 120 ° C.

[Production Method of Toner B-2]
The production method of the toner B-2 was the same as the production method of the toner A-9 except that the temperature of the melt kneading (cylinder temperature) was changed from 100 ° C. to 120 ° C.

[Method for Producing Toner C-1]
The production method of the toner C-1 was the same as the production method of the toner A-2 except that the shell material polymerization temperature was changed from 70 ° C. to 60 ° C.

[Production Method of Toner C-2]
The production method of the toner C-2 was the same as the production method of the toner A-3 except that the shell material polymerization temperature was changed from 70 ° C. to 60 ° C.

[Method for Producing Toner D-1]
The production method of the toner D-1 was the same as the production method of the toner A-1, except that the amount of the first binder resin (crystalline polyester resin A) used was changed from 100 g to 150 g.

[Production Method of Toner D-2]
The production method of the toner D-2 was the same as the production method of the toner A-6 except that the amount of the first binder resin (crystalline polyester resin A) used was changed from 100 g to 150 g.

[Production Method of Toner D-3]
The production method of the toner D-3 was the same as the production method of the toner A-7, except that the amount of the first binder resin (crystalline polyester resin A) was changed from 100 g to 150 g.

[Evaluation method]
The evaluation method of each sample (toners A-1 to D-3) is as follows.

(Minimum fixing temperature)
100 parts by mass of a developer carrier (FS-C5250DN carrier) and 5 parts by mass of a sample (toner) were mixed for 30 minutes using a ball mill to prepare a two-component developer.

  An image was formed using the two-component developer prepared as described above, and the minimum fixing temperature was evaluated. As an evaluation machine, a color printer (an evaluation machine in which “FS-C5250DN” manufactured by Kyocera Document Solutions Co., Ltd. was modified so that the fixing temperature can be changed) having a Roller-Roller type heating and pressure type fixing device was used. The two-component developer prepared as described above was put into the developing device of the evaluation machine, and the sample (supplementary toner) was put into the toner container of the evaluation machine.

Using the above evaluation machine, a solid image having a size of 25 mm × 25 mm was formed on 90 g / m ² paper (A4 size evaluation paper) under the conditions of a linear speed of 200 mm / sec and a toner applied amount of 1.0 mg / cm ^2. Formed. Subsequently, the paper on which the image was formed was passed through the fixing device of the evaluation machine.

  In the evaluation of the minimum fixing temperature, the setting range of the fixing temperature was 100 ° C. or higher and 200 ° C. or lower. Specifically, the fixing temperature of the fixing device is increased from 100 ° C. by 5 ° C. (however, in the vicinity of the minimum fixing temperature by 2 ° C.), and the minimum temperature (minimum fixing temperature) at which a solid image (toner image) can be fixed on paper is set. It was measured. Whether or not the toner could be fixed was confirmed by a rubbing test as shown below. Specifically, the evaluation paper passed through the fixing device was folded in half so that the surface on which the image was formed was on the inside, and the image on the fold was rubbed 5 times with a 1 kg weight coated with a cloth. Subsequently, the paper was spread and the bent portion of the paper (the portion where the solid image was formed) was observed. Then, the length (peeling length) of toner peeling at the bent portion was measured. The lowest temperature among the fixing temperatures at which the peeling length was 1 mm or less was defined as the lowest fixing temperature. When the minimum fixing temperature was 145 ° C. or lower, it was evaluated as “good”, and when the minimum fixing temperature exceeded 145 ° C., it was evaluated as “poor” (not good).

(Heat resistant storage stability)
2 g of the sample (toner) was put in a 20 mL capacity plastic container, and the container was left in a thermostat set at 58 ° C. for 3 hours. Thereafter, the toner taken out from the thermostatic chamber was cooled to room temperature to obtain an evaluation toner.

Subsequently, the obtained toner for evaluation was placed on a sieve having a known mass of 100 mesh (aperture 150 μm). Then, the mass of the sieve containing the toner was measured, and the mass of the toner before sieving was determined. Subsequently, a sieve was set on a powder tester (manufactured by Hosokawa Micron Co., Ltd.), and according to the manual of the powder tester, the sieve was vibrated for 30 seconds under the conditions of the rheostat scale 5, and the evaluation toner was sieved. Then, after sieving, the mass of the toner remaining on the sieve was determined by measuring the mass of the sieve containing the toner. From the mass of the toner before sieving and the mass of the toner after sieving (the mass of the toner remaining on the sieving after sieving), the degree of aggregation (% by mass) was determined based on the following formula.
Aggregation degree (% by mass) = 100 × mass of toner after sieving / mass of toner before sieving

  When the degree of aggregation was 50% by mass or less, it was evaluated as “good”, and when the degree of aggregation exceeded 50% by mass, it was evaluated as “poor” (not good).

(Charge decay constant)
The charge decay constant (charge decay rate) of the sample (toner) was evaluated. As an evaluation machine, an electrostatic diffusivity measuring device (“NS-D100” manufactured by Nano Seeds Co., Ltd.) was used. The evaluation method was a method based on JIS (Japanese Industrial Standard) C 61340-2-1-2006. Hereinafter, a method for evaluating the charge decay constant will be described in detail.

  A sample (toner) was placed in the measurement cell. The measurement cell was a metal cell in which a recess having an inner diameter of 10 mm and a depth of 1 mm was formed. The sample was pushed in from above using a slide glass, and the concave portion of the cell was filled with the sample. The sample overflowed from the cell was removed by reciprocating the slide glass on the surface of the cell. The sample loading was 50 mg.

Subsequently, the measurement cell filled with the sample was allowed to stand for 12 hours in an environment of a temperature of 32 ° C. and a humidity of 80% RH. Subsequently, the grounded measurement cell was set in the evaluator, and zero adjustment of the surface electrometer of the evaluator was performed. Subsequently, the sample was charged by corona discharge under the conditions of a voltage of 10 kV and a charging time of 0.5 seconds. And after 0.7 second passed after completion | finish of corona discharge, the surface potential of the sample was measured continuously. The charge decay constant α was calculated based on the measured surface potential and the formula “V = V ₀ exp (−α√t)”. In the formula, V represents the surface potential [V], V ₀ represents the initial surface potential [V], and t represents the decay time [second].

  When the charge decay constant was 0.025 or less, it was evaluated as ◯ (good), and when the charge decay constant exceeded 0.025, it was evaluated as x (not good).

[Evaluation results]
Table 2 shows the evaluation results for each sample (Toners A-1 to D-3). Table 2 shows the evaluation results of the minimum fixing temperature, heat resistant storage stability, and charge decay constant.

Toners A-1, A-2, A-4, A-6, A-7, B-1, and B-2 (toners according to Examples 1 to 7) each have the above-described basic configuration. It was. Specifically, in the toners according to Examples 1 to 7, the toner particles each contain, as a binder resin, an amorphous polyester resin and a particulate crystalline polyester resin dispersed in the amorphous polyester resin. It was. In each of the toners according to Examples 1 to 7, as shown in Table 1, the dispersion diameter of the crystalline polyester resin was 40 nm or more and 150 nm or less. In each of the toners according to Examples 1 to 7, when the phase delay of the probe of the scanning probe microscope in the cross section of the toner particle is measured in the dynamic mode of the scanning probe microscope, as shown in Table 1, The phase lag A of the probe on the amorphous polyester resin and the phase lag B of the probe on the crystalline polyester resin satisfy the relational expression “−22 ° ≦ B−A ≦ −13 °”. It was. In each of the toners according to Examples 1 to 7, as shown in Table 1, the SP value (SP _A ) of the amorphous polyester resin and the SP value (SP _B ) of the crystalline polyester resin are related. “0.2 J / cm ³ ≦ | SP _A −SP _B | ≦ 1.0 J / cm ³ ” was satisfied.

  As shown in Table 2, the toners according to Examples 1 to 7 are attenuated in charge as compared with the toners A-3 and D-1 to D-3 (the toners according to Comparative Examples 1 and 7 to 9). It was difficult. In addition, as shown in Table 2, toners according to Examples 1 to 7 are toners A-3, A-5, C-1, and C-2 (comparative examples 1, 2, 5, and 6). The toner was excellent in low-temperature fixability as compared with the toner. Further, as shown in Table 2, each of the toners according to Examples 1 to 7 was superior in heat-resistant storage stability as compared with toners A-8 and A-9 (toners according to comparative examples 3 and 4). .

  Each of the toner manufacturing methods according to Examples 1 to 7 was a method including the above-described preferable manufacturing steps (melt kneading of the toner core material, pulverization of the kneaded material, addition of the material, and formation of the shell layer).

  The toner for developing an electrostatic latent image according to the present invention can be used for forming an image in, for example, a copying machine, a printer, or a multifunction machine.

Claims (7)

An electrostatic latent image developing toner comprising a plurality of toner particles containing a binder resin,
The toner particles contain, as the binder resin, an amorphous polyester resin and a particulate crystalline polyester resin dispersed in the amorphous polyester resin,
The dispersion diameter of the crystalline polyester resin is 40 nm or more and 150 nm or less,
When measuring the phase lag of the probe of the scanning probe microscope in the cross section of the toner particle in the dynamic mode of the scanning probe microscope, the phase lag A of the probe on the non-crystalline polyester resin and the A toner for developing an electrostatic latent image, wherein a phase delay B of the probe on a crystalline polyester resin satisfies a relational expression “−22 ° ≦ B−A ≦ −13 °”. When the SP value of the non-crystalline polyester resin is described as SP _A and the SP value of the crystalline polyester resin is described as SP _B , SP _A and SP _B are expressed by the relational expression “0.2 J / cm ³ ≦ | The toner for developing an electrostatic latent image according to claim 1, wherein SP _A −SP _B | ≦ 1.0 J / cm ³ is satisfied.   3. The electrostatic latent image developing toner according to claim 1, wherein the toner particles contain one type of the crystalline polyester resin and a plurality of types of the amorphous polyester resin that are melt-kneaded. The toner particles include a core and a shell layer formed on the surface of the core,
The core is produced by a dry method,
The electrostatic shell image developing toner according to claim 1, wherein the shell layer is formed on a surface of the core by a wet method.   The electrostatic latent image developing toner according to claim 4, wherein the shell layer contains a resin in which one or more styrene monomers and one or more acrylic monomers are crosslinked by a crosslinking agent.   The said cross-linked resin has an alcoholic hydroxyl group derived from 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, or 2-hydroxypropyl methacrylate. Toner for electrostatic latent image development. A method for producing the toner for developing an electrostatic latent image according to any one of claims 4 to 6,
The core material containing at least the non-crystalline polyester resin and the crystalline polyester resin is melt-kneaded to obtain a kneaded product containing the crystalline polyester resin having a dispersion diameter not in the range of 40 nm to 150 nm. When,
Crushing the kneaded product to obtain the core;
Placing the core and the material of the shell layer in an aqueous medium;
By polymerizing the material of the shell layer in the aqueous medium, the dispersion diameter of the crystalline polyester resin in the core is set to 40 nm or more and 150 nm or less, and the shell layer is formed on the surface of the core. When,
A method for producing a toner for developing an electrostatic latent image, comprising:

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