JP2018017918A - Electrostatic latent image developing toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic latent image developing toner which is excellent in terms of the heat-resistant storage property, the charging stability, and the fixability.SOLUTION: The electrostatic latent image developing toner includes a binder resin and a separation agent. The binder resin includes a crystalline resin and a non-crystalline resin. A differential heat amount curve measured by a differential scanning calorimeter has a first endothermic peak P1 in a 50°C-60°C temperature range and a second endothermic peak P2 in a 65°C-95°C temperature range in a first temperature rising process, and a third endothermic peak P3 in a 65°C-95°C temperature range in a second temperature rising process. There is no peaks derived from a glass transition point in a 10°C-150°C temperature range.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electrostatic latent image developing toner.

  The electrostatic latent image developing toner described in Patent Document 1 has a crystalline resin and a release agent. The melting point of the crystalline resin and the melting point of the release agent have a predetermined relationship. Furthermore, the ratio of the endothermic amounts of the two endothermic peaks in the first temperature rising process obtained by differential scanning calorimetry has a predetermined relationship, and the ratio of the endothermic amounts of the two endothermic peaks in the second temperature rising process is predetermined. Have the relationship.

JP 2009-237098 A

  However, it is difficult to provide a toner for developing an electrostatic latent image that has both excellent heat-resistant storage stability, excellent charging stability, and excellent fixability only by the technique described in Patent Document 1.

  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 has excellent heat-resistant storage stability, excellent charging stability, and excellent fixing properties. .

  The toner for developing an electrostatic latent image of the present invention contains a binder resin and a release agent. The differential calorimetric curve measured by the differential scanning calorimeter has a first endothermic peak P1 in the temperature range of 50 ° C. or higher and 60 ° C. or lower and a second endotherm in the temperature range of 65 ° C. or higher and 95 ° C. or lower in the first temperature rising process. It has a peak P2. The second endothermic process has a third endothermic peak P3 in the temperature range of 65 ° C. or more and 95 ° C. or less, and no peak derived from the glass transition point in the temperature range of 10 ° C. or more and 150 ° C. or less. The first temperature raising process is executed at a temperature raising rate of 10 ° C./min from the first temperature raising start temperature of 10 ° C. to the first temperature raising end temperature of 150 ° C. In the second temperature raising process, after the first temperature raising process, the first temperature raising end temperature is maintained for 2 minutes, from the first temperature raising end temperature 150 ° C. to the second temperature rising start temperature 10 ° C. The temperature is lowered at a rate of temperature decrease of 10 ° C./min, and the second temperature rise start temperature is maintained for 3 minutes. Then, the temperature rise rate is 10 ° C./second from the second temperature rise start temperature 10 ° C. to the second temperature rise end temperature 150 ° C. Executed in minutes.

  According to the present invention, it is possible to provide a toner for developing an electrostatic latent image that has excellent heat-resistant storage stability, excellent charging stability, and excellent fixing properties.

It is a figure which shows the differential calorific value curve measured in the temperature rising process of the 1st time. It is a figure which shows the differential calorific value curve measured in the temperature rising process of the 2nd time. It is a figure which shows the temperature profile in the measurement of a differential calorific value curve.

  Hereinafter, embodiments of the present invention will be described in detail. The present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the object of the present invention. In addition, about the location where description overlaps, although description may be abbreviate | omitted suitably, the summary of invention is not limited.

  The electrostatic latent image developing toner according to the present embodiment (hereinafter sometimes referred to as toner) is a powder composed of a large number of toner particles. The toner according to the exemplary embodiment can be used in, for example, an electrophotographic apparatus (image forming apparatus).

  In an electrophotographic apparatus, an electrostatic latent image is developed using a developer containing toner. In the developing step, charged toner is attached to the electrostatic latent image formed on the photoconductor to form a toner image on the photoconductor. In the subsequent transfer process, the toner image on the photosensitive member is transferred to an intermediate transfer member (for example, an intermediate 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 this embodiment has the following configuration (1).
Configuration (1): The binder resin includes a crystalline resin and an amorphous resin. The differential calorimetric curve measured by the differential scanning calorimeter has a first endothermic peak P1 in the temperature range of 50 ° C. or higher and 60 ° C. or lower and a second endotherm in the temperature range of 65 ° C. or higher and 95 ° C. or lower in the first temperature rising process. It has a peak P2. The second endothermic process has a third endothermic peak P3 in the temperature range of 65 ° C. or more and 95 ° C. or less, and no peak derived from the glass transition point in the temperature range of 10 ° C. or more and 150 ° C. or less.

  FIG. 1 shows a differential calorific value curve measured in the first temperature raising process. In FIG. 1, the horizontal axis represents temperature, and the vertical axis represents heat flux. This differential calorimetric curve has two peaks. The peak of the temperature P1 located on the low temperature side (hereinafter sometimes referred to as the first endothermic peak P1) and the peak of the temperature P2 located on the high temperature side (hereinafter sometimes referred to as the second endothermic peak P2) It is.

  FIG. 2 shows a differential calorimetric curve measured in the second temperature raising process. In FIG. 2, the horizontal axis indicates the temperature, and the vertical axis indicates the heat flux. This differential calorimetric curve has one peak of temperature P3 (hereinafter sometimes referred to as a third endothermic peak P3).

  The glass transition point Tg of the toner can be obtained from the differential calorific value curve. As shown in FIG. 1, the temperature at the intersection corresponds to the glass transition point Tg. This intersection is an intersection of an extension of the baseline on the low temperature side and a tangent at the inflection point in the differential calorific curve on the low temperature side. The glass transition point Tg can be obtained from a differential calorific curve having two peaks (for example, the differential calorific curve shown in FIG. 1), and a differential calorimetric curve having only one peak (for example, the differential calorific value shown in FIG. 2). (Curve) cannot be obtained.

  The differential calorimetric curve is measured at a two temperature increase using a differential scanning calorimeter (for example, “DSC-6220” manufactured by Seiko Instruments Inc.). FIG. 3 shows a temperature profile in the measurement of the differential calorimetric curve. In FIG. 3, the horizontal axis represents time (unit: minutes), and the vertical axis represents temperature (unit: ° C.). The first temperature raising process is executed at a temperature raising rate of 10 ° C./min from the first temperature raising start temperature of 10 ° C. to the first temperature raising end temperature of 150 ° C. In the second temperature raising process, after the first temperature raising process, the first temperature rising end temperature 150 ° C. is maintained for 2 minutes, and the second temperature rising start temperature 10 ° C. from the first temperature rising end temperature 150 ° C. The temperature is decreased to 10 ° C. at a rate of temperature decrease of 10 ° C./min, and the second temperature rise start temperature of 10 ° C. is maintained for 3 minutes, and then the temperature rise is increased from the second temperature increase start temperature of 10 ° C. to the second temperature increase end temperature of 150 ° C. Run at a rate of 10 ° C / min.

  The configuration (1) is beneficial for the parallelism of excellent heat-resistant storage stability, excellent charging stability, and excellent fixability of the toner. In the toner having the configuration (1), the differential calorimetric curve measured in the second temperature raising process does not have a peak derived from the glass transition point Tg in a predetermined temperature range, and thus the crystal in the first temperature raising process. There is a tendency that the crystalline resin and the amorphous resin are compatible. For this reason, in the toner having the configuration (1), the crystalline resin is uniformly dispersed in the amorphous resin. Therefore, the toner having the configuration (1) is considered to have excellent heat-resistant storage stability, excellent charging stability, and excellent fixing properties.

  In the toner having the configuration (1), the differential heat quantity curve measured in the first temperature rising process has the first endothermic peak P1 and the second endothermic peak P2 in a predetermined temperature range, and the non-crystal of the binder resin. The glass transition point Tg derived from the structure is confirmed. Further, in the toner having the configuration (1), the differential calorimetric curve measured in the second temperature raising process has only the third endothermic peak P3 in a predetermined temperature range, and is derived from the amorphous structure of the binder resin. The glass transition point Tg to be confirmed is not confirmed. Therefore, in the toner having the configuration (1), since the crystalline resin tends to be sufficiently crystallized, there is little crystalline resin that is not crystallized, and the crystalline resin is not easily crystallized due to change over time. it is conceivable that. Therefore, the toner having the configuration (1) is considered to have excellent heat-resistant storage stability, excellent charging stability, and excellent fixing properties.

  In the toner having the configuration (1), the endothermic amount ΔH1 of the first endothermic peak P1 is observed in the first temperature rising process. ΔH1 corresponds to enthalpy relaxation derived from the amorphous structure of the binder resin. In the toner in which ΔH1 is observed, the molecular state in the binder resin hardly changes, and the change with time does not easily occur. Therefore, the toner having the configuration (1) is considered to be excellent in heat-resistant storage stability and charging stability.

  In the toner having the configuration (1), the first endothermic peak P1 and the second endothermic peak P2 are observed in a predetermined temperature range. In such a case, the glass transition point Tg of the toner and the melting temperature of the release agent and the crystalline resin tend to be 45 ° C. or higher and 55 ° C. or lower. When the glass transition point Tg of the toner is in the above temperature range, excellent heat resistant storage stability and fixability tend to be exhibited in the toner usage environment. Therefore, the toner having the configuration (1) is considered to be excellent in heat resistant storage stability and fixing property.

  From the above, it is considered that the toner having the configuration (1) has excellent heat-resistant storage stability, excellent charging stability, and excellent fixing properties.

In order to further improve the heat resistant storage stability, charging stability, and fixability of the toner, the toner has the following constitution (2), constitution (3), and constitution (4) in addition to the constitution (1). It is preferable to have at least one of them.
Configuration (2): The endothermic amount ΔH1 of the first endothermic peak P1 satisfies the following formula (A).
ΔH1 ≧ 2.0 J / g (A)
Configuration (3): The endothermic amount ΔH1 of the first endothermic peak P1, the endothermic amount ΔH2 of the second endothermic peak P2, and the endothermic amount ΔH3 of the third endothermic peak P3 satisfy the following formula (B).
2.0 J / g ≦ ΔH 1 + ΔH 2 −ΔH 3 ≦ 6.0 J / g (B)
Configuration (4): The solubility parameter SP _C of the crystalline resin and the solubility parameter SP _A of the amorphous resin satisfy the following formula (C).
| SP _C -SP _A | ≧ 0.4 (C)

  The endothermic amount can be obtained from a differential calorimetric curve. The endothermic amount ΔH1 of the first endothermic peak P1 corresponds to a region surrounded by the differential heat amount curve on the low temperature side and the broken line in FIG. As shown in FIG. 1, this broken line is obtained by connecting the base line on the low temperature side and the maximum point of the differential calorific value curve. The endothermic amount ΔH2 of the second endothermic peak P2 corresponds to a region surrounded by a high-temperature differential heat amount curve and a broken line in FIG. As shown in FIG. 1, this broken line is obtained by connecting the base line on the high temperature side and the maximum value of the differential calorific value curve. The endothermic amount ΔH3 of the third endothermic peak P3 corresponds to a region surrounded by the differential heat amount curve and the broken line in FIG. As shown in FIG. 2, this broken line is obtained by connecting the base lines of the low temperature side and the high temperature side.

The solubility parameter (SP value) is a characteristic value that serves as an index of compatibility. The SP value is represented by the square root of the cohesive energy density (CED). CED is the amount of energy required to evaporate 1 mL of molecules. Hereinafter, based on the following document A and document B, the calculation method of SP value is demonstrated.
Reference A: R.M. F. Fedors, “Polymer Engineering and Science”, 1974, Vol. 14, No. 2, p147-154
Reference B: Akira Imoto, “Basic Theory of Adhesion”, Polymer Publishing Society, 1993

The SP value is represented by the formula “SP value = (E / V) ^1/2 ” (E: molecular cohesive energy [cal / mol], V: molecular volume [cm ³ / mol]). E (molecular cohesive energy) in the formula is represented by the formula “E = ΣΔei” (Δei: evaporation energy of atomic group). V (molecular volume) in the formula is represented by the formula “V = ΣΔvi” (Δvi: molar volume of atomic group). The SP value can be calculated using Fedors' evaporation energy value (see Document A) and the data of Δei and Δvi described in Document B. For example, when calculating SP _T , the atomic groups associated with each of Δei and Δvi correspond to atomic groups included in the binder resin.

  Hereinafter, a method for adjusting the SP value will be described. The SP value of the resin decreases as the hydrophobicity of the binder resin increases, and the SP value of the binder resin tends to increase as the hydrophilicity of the binder resin increases. The SP value of the binder resin can be adjusted by, for example, introducing a substituent to the binder resin or changing the ratio of the repeating unit in the binder resin. When a substituent is introduced into the binder resin, the SP value of the binder resin can be adjusted depending on the type of substituent to be introduced or the number of substituents to be introduced. For example, the SP value of the binder resin can be lowered by introducing a hydrophobic substituent into the binder resin. Examples of the hydrophobic substituent include an alkyl group, an alkenyl group, an alkynyl group, and an aryl group. Further, the SP value of the binder resin can be increased by introducing a hydrophilic substituent into the binder resin. Examples of the hydrophilic substituent include a hydroxyl group, a carboxyl group, a cyano group, a nitro group, and an amino group.

  Further, when the binder resin is a copolymer, the SP value of the binder resin can be adjusted by changing the ratio of two or more kinds of repeating units contained in the binder resin. For example, the SP value of the binder resin can be lowered by increasing the proportion of hydrophobic repeating units in the binder resin. Further, the SP value of the binder resin can be increased by increasing the ratio of hydrophilic repeating units in the binder resin.

  In the toner having the configuration (2), since the endothermic amount ΔH1 of the first endothermic peak P1 is 2.0 J / g or more, the amorphous resin in the toner particles tends to have a more stable molecular structure in terms of thermal energy. It is in. Therefore, the toner having the configuration (2) is excellent in charging stability and heat resistant storage stability.

  In the toner having the configuration (3), the endothermic amount ΔH1 of the first endothermic peak, the endothermic amount ΔH2 of the second endothermic peak, and the endothermic amount ΔH3 of the third endothermic peak satisfy the formula (B). It is shown that the crystalline resin is crystallized and present. Therefore, the toner having the configuration (3) has excellent heat-resistant storage stability and excellent fixability at low temperatures.

In the toner having the configuration (4), the solubility parameter SP _C of the crystalline resin and the solubility parameter SP _{A of the} amorphous resin satisfy the formula (C). There is a tendency that the crystalline resin and the amorphous resin are not excessively compatible with each other in the toner particles and are stable in terms of thermal energy. Therefore, ΔH1 easily satisfies the formula (A), crystallization of the crystalline resin is promoted, and the heat resistant storage stability and charging stability of the toner are easily improved.

  In addition to the configuration (4), the adjustment of ΔH1 can be performed by heat treatment in the toner manufacturing process. Details of the heat treatment will be described later in the item “Production method of toner”.

  The toner according to the present embodiment includes a plurality of toner particles having the configuration (1) (hereinafter referred to as toner particles according to the present embodiment). The toner preferably has the toner particles of the present embodiment at a ratio of 80% by number or more, more preferably has the toner particles of the present embodiment at a ratio of 90% by number or more, and the toner particles of the present embodiment have a ratio of 100% by number. It is further preferred to have toner particles in the form.

  The toner particles contained in the toner may be toner particles having no shell layer (hereinafter sometimes referred to as non-capsule toner particles) or toner particles having a shell layer (hereinafter referred to as capsule toner particles). May be). The capsule toner particle has a toner core and a shell layer that covers the surface of the toner core. An external additive may be attached to the surface of the 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 may be referred to as toner mother particles.

  The toner may be used as a one-component developer. Further, a two-component developer may be prepared by mixing toner with a desired carrier. The toner may be used as a positively chargeable toner.

  Hereinafter, the toner base particles and the external additive will be described in order. Further, a toner manufacturing method will be described. In the case of capsule toner particles, the following toner base particles can be used as the toner core. Acrylic and methacrylic are sometimes collectively referred to as “(meth) acrylic”. In addition, a compound and a derivative thereof 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.

[Toner mother particles]
The toner base particles include a binder resin and a release agent. The toner base particles may contain an internal additive (for example, a colorant, a charge control agent, or a magnetic powder) in addition to the binder resin and the release agent. Hereinafter, the binder resin, the release agent, the colorant, the charge control agent, and the magnetic powder will be described.

(Binder resin)
In the toner mother particles, 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 base particles. 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 base particles tend to be anionic, and the binder resin has an amino group or an amide group. When it is included, the toner base particles tend to be cationic. In order for the binder resin to have a strong anionic property, the hydroxyl value (OHV value) and the acid value (AV value) of the binder resin are each preferably 10 mgKOH / g or more, and each 20 mgKOH / g or more. Is more preferable. Further, an anionic compound (for example, a compound having an ester group, a hydroxyl group, an ether group, an acid group, or a methyl group) may be added to the toner base particles to impart an anionic property to the toner base particles. Further, a cationic compound (for example, a compound having an amino group or an amide group (more specifically, an amine or the like)) may be added to the toner base particles to impart cationicity to the toner base particles. .

  The glass transition point (Tg) of the binder resin is preferably 30 ° C. or higher and 80 ° C. or lower, and more preferably 45 ° C. or higher and 55 ° C. or lower.

  The Tg of the binder resin can be measured using, for example, a differential scanning calorimeter. More specifically, by measuring the endothermic curve of the sample (binder resin) using a differential scanning calorimeter, the Tg of the binder resin can be obtained from the change point of specific heat in the obtained endothermic curve.

  The softening point (Tm) of the binder resin is preferably 120 ° C. or lower. When the Tm of the binder resin is 120 ° C. or less, the toner fixability is hardly lowered even during high-speed fixing on the recording medium.

The Tm of the binder resin can be measured using, for example, a Koka type flow tester (more specifically, “CFT-500D” manufactured by Shimadzu Corporation). More specifically, a sample (binder resin) is set in the Koka flow tester, and the binder resin is melted and discharged under predetermined conditions. Then, the S-curve of the binder resin is measured. The Tm of the binder resin can be read from the obtained S-shaped curve. In the obtained S-curve, if the maximum stroke value is S ₁ and the low-temperature baseline stroke value is S ₂ , the stroke value in the S-curve is “(S ₁ + S ₂ ) / 2”. The temperature (° C.) at which corresponds to the Tm of the measurement sample (binder resin).

  The binder resin includes a crystalline resin and an amorphous resin. Examples of the crystalline resin include a crystalline polyester resin, a crystalline polyurethane resin, a crystalline polyamide resin, and a crystalline polyether resin. These crystalline resins may be copolymers. These crystalline resins may be used singly or in combination of two or more. Of these crystalline resins, crystalline polyester resins are preferred.

  The crystalline polyester resin is obtained, for example, by condensation polymerization or co-condensation polymerization of an alcohol component and a carboxylic acid component. A divalent or trivalent or higher alcohol can be used as the alcohol component. Specific examples of the divalent or trivalent or higher alcohol component include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1 , Diols such as 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, or polytetramethylene glycol; bisphenol A, hydrogenated bisphenol A, Bisphenols such as polyoxyethylene bisphenol A or polyoxypropylene bisphenol A; sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol Dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, diglycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, Examples thereof include trivalent or higher alcohols such as trimethylolethane, trimethylolpropane, or 1,3,5-trihydroxymethylbenzene.

  Among these alcohol components, since crystallization of the polyester resin is easily promoted, aliphatic diols having 2 to 8 carbon atoms are preferable, and α, ω-alkanediols having 2 to 8 carbon atoms are preferable. More preferred is 1,4-butanediol or 1,6-hexanediol.

  In order to obtain a crystalline polyester resin, the proportion of the aliphatic diol having 2 to 10 carbon atoms in the alcohol component is preferably 80 mol% or more, more preferably 90 mol% or more. Similarly, the content of the component (single compound) contained in the largest amount in the alcohol component is preferably 70 mol% or more, more preferably 90 mol% or more, and 100 mol%. Most preferred.

  As the carboxylic acid component, a divalent or trivalent or higher carboxylic acid can be used. Specific examples of the divalent or trivalent or higher carboxylic acid component include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, Sebacic acid, azelaic acid, malonic acid, alkyl succinic acid or alkenyl succinic acid (for example, n-butyl succinic acid, n-butenyl succinic acid, isobutyl succinic acid, isobutenyl succinic acid, n-octyl succinic acid, n-octenyl succinic acid, divalent carboxylic acids such as n-dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid or isododecenyl succinic acid); 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5 , 7-Naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1 2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) Trivalent or higher carboxylic acids such as methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, or empole trimer acid can be mentioned. These divalent or trivalent or higher carboxylic acid components may be transformed into an ester-forming derivative such as a carboxylic acid halide, a carboxylic acid anhydride, or a lower alkyl ester. Here, “lower alkyl” means an alkyl group having 1 to 6 carbon atoms.

  Among these carboxylic acid components, an aliphatic dicarboxylic acid having 2 to 16 carbon atoms is preferable because α-ω has 2 to 16 carbon atoms. Alkanedicarboxylic acid is more preferred. The carboxylic acid component may further contain a monovalent carboxylic acid. Examples of the monovalent carboxylic acid include stearic acid.

  In order to obtain a crystalline polyester resin, the aliphatic dicarboxylic acid having 2 to 16 carbon atoms in the carboxylic acid component is preferably 70 mol% or more, and more preferably 90 mol% or more. Similarly, the content of the component (single compound) contained in the largest amount in the carboxylic acid component is preferably 70 mol% or more, more preferably 90 mol% or more, and 100 mol%. Is most preferred.

  The content of the crystalline polyester resin is preferably 1 part by mass or more and 20 parts by mass or less, and more preferably 5 parts by mass or more and 15 parts by mass or less with respect to 100 parts by mass of the toner particles. When the content of the crystalline polyester resin is 1 part by mass or more and 15 parts by mass or less, the low-temperature fixability of the toner is improved and the toner is difficult to be negatively charged.

  In order to improve the low-temperature fixability of the toner and effectively suppress the occurrence of offset when fixing at a high temperature, the crystallinity index of the crystalline polyester resin is 0.98 or more and 1.05 or less. preferable.

  Examples of the amorphous resin include a vinyl resin and a non-vinyl resin. Examples of the vinyl resin include a polymer of a monomer having a vinyl group (more specifically, a styrene resin, an acrylic acid resin, an olefin resin, or the like). Examples of the non-vinyl resin include cellulose resin, polyester resin, epoxy resin, polyurethane resin, polyamide resin, and polyether resin. These amorphous resins may be copolymers. These amorphous resins may be used singly or in combination of two or more. Of these non-crystalline resins, non-crystalline polyester resins are preferred.

  The amorphous polyester resin will be described. When preparing an amorphous polyester resin, it is necessary to suppress crystallization of the obtained polyester resin. The method for suppressing crystallization of the polyester resin is not particularly limited, and examples of general crystallization suppressing methods include the following methods (1) to (3).

  Method (1): A method in which only a small amount of alcohol and carboxylic acid that promotes crystallization of the crystalline polyester resin are used or not.

  Method (2): A method of using two or more compounds as alcohol and carboxylic acid.

  Method (3): A method of suppressing crystallization by using an alcohol such as an alkylene oxide adduct of bisphenol A or a carboxylic acid such as an alkyl-substituted succinic acid.

  Among these methods for suppressing crystallization, the method (3) is more preferable because the number of types of monomers is small and the preparation of an amorphous polyester resin is easy. In the method (3), the crystallization is more easily suppressed as the amounts of the alcohol (for example, the alkylene oxide adduct of bisphenol A) and the carboxylic acid (for example, the alkyl-substituted succinic acid) are increased. However, the amount of these monomers used is preferably adjusted as appropriate in consideration of the crystallinity index of the resulting polyester and other physical properties. In addition, an amorphous polyester resin may be used independently and may be used in combination of 2 or more type.

  The content of the amorphous polyester resin is preferably 75 parts by mass or more and 90 parts by mass or less, and more preferably 80 parts by mass or more and 85 parts by mass or less with respect to 100 parts by mass of the toner particles.

  When the toner particles contain a crystalline polyester resin and an amorphous polyester resin, in order to improve the low-temperature fixability of the toner and suppress the occurrence of hot offset, crystals with respect to the content Q of the amorphous polyester resin The ratio P / Q of the content P of the conductive polyester resin is preferably 1 or less.

(Release agent)
The toner base particles 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 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. More preferably, it is 10 parts by mass or less.

  Preferable 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 an oxide of an aliphatic hydrocarbon wax such as a block copolymer of oxidized polyethylene wax; a plant wax such as candelilla wax, carnauba wax, wood wax, jojoba wax, or rice wax; beeswax, lanolin, or Animal waxes such as whale wax; mineral waxes such as ozokerite, ceresin, or petrolatum; waxes based on fatty acid esters such as montanate wax or castor wax; Such as carnauba wax, part or all of fatty acid esters are de-oxidized waxes. Among these release agents, the melting point is preferably 65 ° C. or higher and 95 ° C. or lower. Examples of such a release agent include polyethylene wax, paraffin wax, Fischer-Tropsch wax, synthetic ester wax, carnauba wax, and microcrystalline wax.

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

(Coloring agent)
The toner base particles may contain a colorant. As the colorant, for example, a known pigment or dye can be used according to the color of the toner. The amount of the colorant used is preferably 1 part by mass or more and 20 parts by mass or less, and more preferably 3 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the binder resin.

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

  Examples of yellow colorants include condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal complexes, methine compounds, or arylamide compounds. Suitable examples of yellow colorants 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. Bat yellow is mentioned.

  Examples of magenta colorants include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, or perylene compounds. Suitable examples of magenta colorants 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).

  Examples of cyan colorants include copper phthalocyanine compounds, anthraquinone compounds, or basic dye lake compounds. Suitable 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.

(Charge control agent)
The toner base particles may contain a charge control agent. The charge control agent is used, for example, for the purpose of improving the charging stability or charge rising property of the toner. The toner charge rising property is an index of whether or not the toner can be charged to a predetermined charge level in a short time. The charge control agent may be a polymer type charge control agent (charge control resin (CCR)).

(Magnetic powder)
The toner base particles may contain magnetic powder. Examples of magnetic powders include iron (more specifically, ferrite or magnetite), ferromagnetic metal (more specifically, cobalt or nickel), a compound containing iron and / or ferromagnetic metal (more specifically, In particular, an alloy or the like), a ferromagnetic alloy that has been subjected to a ferromagnetization treatment (more specifically, a heat treatment or the like), or chromium dioxide.

  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 a metal ion adheres to the surface of the toner core, the toner core and another toner core are easily fixed. By suppressing the elution of metal ions from the magnetic powder, it is possible to suppress adhesion between the toner core and another toner core.

[External additive]
An external additive may be attached to the surface of the toner particles for the purpose of imparting fluidity, chargeability, abrasiveness, or heat-resistant storage stability to the toner. Examples of the external additive include metal oxides (more specifically, alumina, titanium oxide, magnesium oxide, zinc oxide, tin oxide, strontium titanate, magnesium titanate, calcium titanate, strontium titanate, or titanium. Barium acid, etc.), zinc stearate, silica particles, or organic particles.

  The volume median diameter of the external additive is preferably 0.01 μm or more and 1.0 μm or less. The amount of the external additive used is preferably 0.5 parts by mass or more and 10 parts by mass or less, more preferably 1 part by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the toner base particles.

[Toner Production Method]
Hereinafter, a toner manufacturing method will be described. The toner manufacturing method includes, for example, a toner base particle preparation step and an external addition step. In the toner base particle preparation step, toner base particles are prepared. In the external addition step, an external additive is attached to the surface of the toner base particles.

(Toner base particle preparation process)
As the toner base particle preparation step, for example, a pulverization method or an aggregation method is preferable.

  In the pulverization method, a binder resin, a release agent, and an internal additive (for example, a colorant, a charge control agent, or magnetic powder) are mixed. Subsequently, the obtained mixture is melted and kneaded. Subsequently, the obtained kneaded material is pulverized. Subsequently, the obtained pulverized product is classified. As a result, toner base particles having a desired particle diameter are obtained. According to the pulverization method, toner mother particles can be prepared relatively easily. The toner base particles are preferably prepared by a pulverization method.

  ΔH1 can be adjusted by cooling the kneaded product and annealing the pulverized product in the pulverization method. Examples of the cooling conditions for the kneaded product include a cooling time, a cooling rate, and a cooling temperature. Among these, the cooling time or the cooling temperature at a temperature below the glass transition temperature Tg of the amorphous resin is considered to be particularly affected.

  Examples of the annealing treatment of the pulverized product in the pulverization method include standing for a certain period of time at a temperature lower than the melting point of the crystalline resin (more specifically, 24 hours or more in a 40 ° C. environment). The temperature lower than the melting point of the crystalline resin is preferably a temperature that is 10 ° C. or more and 30 ° C. or less lower than the melting point of the crystalline resin. A temperature equal to or higher than the glass transition point Tg of the crystalline resin is preferable. By applying such annealing treatment to the toner base particles, the crystallization of the crystalline resin can be sufficiently achieved, so that the state change is less likely to occur due to the crystallization of the crystalline resin, and ΔH1 is expressed by the formula (A). It becomes easy to satisfy.

  The aggregation method includes, for example, an aggregation process and a coalescence process. In the aggregation step, a plurality of types of particles that are made into particles for each component constituting the toner base particles are aggregated in an aqueous medium to form aggregated particles including a plurality of types of toner base particle components. In the coalescence process, the toner contained in the aggregated particles is coalesced in an aqueous medium to obtain toner base particles. According to the aggregation method, it is easy to obtain toner base particles having a uniform shape and a uniform particle diameter.

(External addition process)
In the external addition step, an external additive is attached to the surface of the toner base particles. As a suitable method for attaching the external additive, a toner (for example, FM mixer or Nauter mixer (registered trademark)) is used, under the condition that the external additive is not buried in the surface of the toner base particles. A method of mixing the base particles and the external additive can be mentioned.

  Various processes may be omitted depending on the use of the toner. 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. In order to produce the toner efficiently, it is preferable to form a large number of toner particles simultaneously.

  Examples will be described below. Table 1 shows toners (A-1) to (A-4) and toners (B-1) to (B-6).

(Preparation of amorphous polyester resin A)
(Amorphous polyester resin A-1)
A four-necked flask was used as a reaction vessel. The four-necked flask was a 5 L reaction vessel equipped with a thermometer, a nitrogen introduction tube, a dehydration tube, a rectifying column, a stirring blade, and a thermocouple. The reaction vessel was set in an oil bath. 80 parts by mass of a propylene oxide adduct (BPA-PO) of bisphenol A as an alcohol monomer, 100 parts by mass of an ethylene oxide adduct (BPA-EO) of bisphenol A, 135 parts by mass of terephthalic acid and isophthalic acid as a carboxylic acid monomer 200 parts by mass of acid and 3 parts by mass of dibutyltin oxide as a catalyst were charged into a reaction vessel. Subsequently, the internal temperature of the reaction vessel was raised to 250 ° C. using a hot water bath. The internal temperature of the reaction vessel was kept at 250 ° C., and the reaction was performed for 6 hours under a nitrogen atmosphere. Furthermore, the pressure in the reaction vessel was reduced to 10 mmHg or more and 15 mmHg or less. The internal temperature of the reaction vessel was kept at 250 ° C., and the pressure in the reaction vessel was kept at the above reduced pressure state, and the reaction was carried out for 8 hours. As a result, an amorphous polyester resin A was obtained. The glass transition temperature of the amorphous polyester resin A-1 was 53 ° C. The SP value of the amorphous polyester resin A-1 was 10.8.

(Amorphous polyester resin A-2 to A-3)
An amorphous polyester resin A-2 was produced in the same manner as the amorphous polyester resin A-1, except that isophthalic acid was changed to sebacic acid and terephthalic acid. The glass transition point of the amorphous polyester resin A-2 was 54 ° C. The SP value of the amorphous polyester resin A-2 was 10.6.

(Amorphous polyester resin A-3)
Amorphous polyester resin A-3 was produced in the same manner as amorphous polyester resin A-1, except that isophthalic acid was changed to sebacic acid and the reaction time was changed from 8 hours to 6 hours. The glass transition point of the amorphous polyester resin A-3 was 45 ° C. The SP value of the amorphous polyester resin A-3 was 10.9.

(Preparation of crystalline polyester resin B)
(Crystalline polyester resin B-1)
A four-necked flask was used as a reaction vessel. The four-necked flask is a 5 L reaction vessel equipped with a thermometer, a nitrogen introduction tube, a dehydration tube, a rectifying column, a stirring blade, and a thermocouple. The reaction vessel was set in an oil bath. 120 parts by mass of 1,6-hexanediol and 140 parts by mass of fumaric acid as a carboxylic acid monomer were added. Subsequently, the internal temperature of the reaction vessel was raised to 250 ° C. using an oil bath. The internal temperature of the reaction vessel was kept at 250 ° C., and the reaction was performed for 6 hours under a nitrogen atmosphere. As a result, crystalline polyester resin B-1 was obtained. The crystalline polyester resin B-1 obtained had an endothermic peak temperature of 78 ° C. The SP value of the crystalline polyester resin B-1 was 10.7.

(Crystalline polyester resin B-2)
A crystalline polyester resin B-2 is produced in the same manner as the crystalline polyester resin B-1, except that 1,6-hexanediol is changed to 1,4-butanediol and fumaric acid is changed to sebacic acid. did. The SP value of the crystalline polyester resin B-2 was 10.4.

(Crystalline polyester resin B-3)
A crystalline polyester resin B-3 was produced in the same manner as the crystalline polyester resin B-1, except that 1,6-hexanediol was changed to ethylene glycol. The SP value of the crystalline polyester resin B-3 was 11.0.

(Preparation of toner C)
(Toner C-1)
The following materials were mixed for 4 minutes using an FM mixer (“FM-20B” manufactured by Nippon Coke Industries Co., Ltd.) at a rotational speed of 2000 rpm to obtain a mixture.
Non-crystalline polyester resin A-1: Addition amount “100 parts by mass”
-Crystalline polyester resin B-1: Addition amount “10 parts by mass”
Colorant (Mitsubishi Chemical Corporation “MA-77”, component: carbon black): addition amount “6 parts by mass”
Release agent (“Nissan Electol (registered trademark) WEP-4” manufactured by NOF Corporation, component: ester wax, melting point: 71 ° C.): addition amount “5 parts by mass”

  Using a twin-screw extruder (“PCM-30” manufactured by Ikegai Co., Ltd.), the mixture obtained was melt-kneaded at a melt kneading temperature (cylinder temperature) of 160 ° C., a rotation speed of 150 rpm, and a processing speed of 100 g / min. A melt-kneaded product was obtained. Using a drum flaker (“MBD30-30” manufactured by Nippon Coke Co., Ltd.), the melt-kneaded product was cooled at a cooling rate of 60 ° C./min so that the temperature of the melt-kneaded product was 45 ° C. As a result, flakes of melt-kneaded material were obtained. Subsequently, the obtained flakes were pulverized using a pulverizer (“Turbo Mill (RS type)” manufactured by Freund Turbo Inc.) to obtain a pulverized product having a volume median diameter of 6.5 μm. Subsequently, the obtained pulverized product was classified with an air classifier (“EJ-L3 type” manufactured by Nittetsu Mining Co., Ltd.) to obtain toner mother particles C-1 (volume median diameter 6.8 μm). .

The following materials were mixed for 10 minutes using an FM mixer (“FM-10B” manufactured by Nippon Coke Industries, Ltd.) to obtain toner C-1.
Toner base particle C-1: addition amount “100 parts by mass”
External additive (“RY-200” silica manufactured by Nippon Aerosil Co., Ltd.): Addition amount “2.0 parts by mass”

(Toners (C-2) to (C-4))
A toner (C-2) was produced in the same manner as the toner (C-1), except that the amorphous polyester resin A-1 was changed to the amorphous polyester resin A-2.

(Toner (C-3))
A toner (C-3) was produced in the same manner as the production method of the toner (C-1) except that the content was changed as described below. The flakes were annealed under the conditions of a temperature of 40 ° C. and a standing time of 24 hours using a square vacuum constant temperature dryer (“DP63” manufactured by Yamato Scientific Co., Ltd.). The flakes were obtained by pulverizing the melt-kneaded product using a turbo mill (“T-250 type” manufactured by Matsubo).

(Toner (C-4))
A toner (C-4) was produced in the same manner as the production method of the toner (C-1) except that the addition amount of the crystalline polyester resin was changed from 10 parts by mass to 12 parts by mass.

(Toners (D-1) to (D-6))
(Toner (D-1))
A toner (D-1) was prepared in the same manner as the toner (C-1), except that the temperature at which the melt-kneaded product was cooled was changed from 45 ° C. to 20 ° C.

(Toner (D-2))
Mold release agent (“Nissan Electol (registered trademark) WEP-4” manufactured by NOF Corporation, component: ester wax, melting point: 71 ° C.) to release agent (“PE520” manufactured by Clariant Chemicals, Inc., component polyethylene wax, melting point) : Toner (D-2) was prepared in the same manner as the preparation method of toner (C-1) except that the temperature was changed to 120 ° C.

(Toner (D-3))
Preparation of toner (C-1) except that amorphous polyester resin A-1 was changed to amorphous polyester resin A-2 and crystalline polyester resin B-1 was changed to crystalline polyester resin B-2 A toner (D-3) was produced in the same manner as in the above method.

(Toner (D-4))
Except for changing the non-crystalline polyester resin A-1 (glass transition point 53 ° C.) to the non-crystalline polyester resin A-3 (glass transition point 45 ° C.), the same procedure as for the toner (C-1) was made. Toner (D-4) was produced.

(Toner (D-5))
A toner (D-5) was produced in the same manner as the toner (C-1), except that the crystalline polyester resin B-1 was changed to the crystalline polyester resin B-3.

(Toner (D-6))
The amorphous polyester resin A-1 (100 parts by mass) is changed to the crystalline polyester resin B-2 (100 parts by mass), and the crystalline polyester resin B-1 (10 parts by mass) is changed to the crystalline polyester resin B-2. A toner (D-6) was produced in the same manner as in the production method of the toner (C-1) except that (2 parts by mass) and the crystalline polyester resin B-3 (12 parts by mass) were changed.

[Evaluation method]
The evaluation methods of the samples (toners (C-1) to (C-4) and toners (D-1) to (D-6)) are as follows.

(Volume median diameter D ₅₀ )
The volume median diameter D ₅₀ was measured using a precision particle size distribution measuring apparatus (“Coulter Counter Multisizer 3” manufactured by Beckman Coulter, Inc.).

(Glass transition point Tg of non-crystalline polyester resin A)
The glass transition point Tg was measured using a differential calorimeter (“DSC-6220” manufactured by Seiko Instruments Inc.).

(Heat resistant storage stability of toner)
3 g of a sample (toner) was weighed in a 20 mL capacity plastic container and left in a thermostat set at 55 ° C. for 3 hours to obtain a sample for storage stability evaluation. Thereafter, the sample for storage stability evaluation was sieved using a sieve of 106 mesh (aperture 150 μm) under the condition of amplitude 2 and time 30 seconds according to the manual of a powder tester (manufactured by Hosokawa Micron Corporation). After sieving, the mass of the sample remaining on the sieve was measured. From the mass of the sample before sieving and the mass of the sample remaining on the sieving after sieving, the degree of aggregation (% by mass) of the toner was calculated according to the following formula.
Aggregation degree (mass%) = (mass of sample remaining on sieve / mass of sample before sieving) × 100
From the calculated degree of aggregation, the heat resistant storage stability of the toner was evaluated according to the following criteria.
A (very good): The degree of aggregation was 3% by mass or less.
○ (Good): The degree of aggregation was more than 3% by mass and 10% by mass or less.
X (Poor): Aggregation degree exceeded 10 mass%.

(Charge stability of toner)
A standard carrier ("P-01" positively charged carrier provided by the Imaging Society of Japan) and a sample (toner) are mixed for 30 minutes using a Turbula (registered trademark) mixer, and two components having a toner content of 7% by mass are mixed. A developer was prepared. The toner charge amount of the two-component developer was measured using a Q / m meter (“MODEL 210HS” manufactured by TREK). Specifically, the toner in the sample 0.10 g (± 0.01 g) is sucked using the suction part of the Q / m meter, and the charge amount is determined based on the amount of the sucked toner and the display of the Q / m meter. Calculated (measurement number n = 3). The obtained charge amount was defined as the charge amount Q1 (unit: μC / g) of the toner before standing. Further, after the sample was allowed to stand for 30 days at a temperature of 25 ° C. and a relative humidity of 50% RH, a two-component developer was prepared in the same manner as described above to obtain a charge amount. The obtained charge amount was defined as the charge amount Q2 (unit: μC / g) of the toner after standing. The charge amount difference was calculated from the obtained Q1 and Q2 using Equation (1).
Charge amount difference = | Q1-Q2 | (1)
The charging stability of the toner was evaluated from the obtained charge amount difference according to the following evaluation criteria.
A (very good): The charge amount difference was 1.5 μC / g or less.
○ (good): The charge amount difference was 3.0 μC / g or less.
X (Poor): Charge amount difference exceeded 3.0 μC / g.

(Toner fixability)
The minimum fixing temperature and the maximum fixing temperature of the toner were measured, and the toner fixability was evaluated.

(Measurement of low-temperature fixing temperature of toner)
A modified machine of a printer (“FS-C5250DN” manufactured by Kyocera Document Solutions Inc.) was used as an evaluation machine. This modified machine is an evaluation machine that has been modified so that the fixing unit of the printer is taken out and the temperature can be adjusted. The fixing unit was a Roller-Roller type heat and pressure type fixing unit. A sample (toner) was set in the evaluation machine. The measurement of the minimum fixing temperature of toner includes four steps (an image forming step, a stress applying step, an peeling observation step, and a determination step). In the image forming process, a toner amount of 1.0 mg / cm ² was transferred to a recording medium (paper, CC90, 90 g / m ² ). The toner image transferred onto the recording medium was fixed. The fixing conditions were a linear velocity of 200 mm / second, a fixing temperature of 100 ° C., a distance between nips of 8 mm, and a nip passage time of 40 milliseconds. As a result, a solid image (image density 100%) was obtained. In the step of applying stress to the image, the solid image was folded in half so that the solid image on the recording medium was inside. Then, the recording medium was rubbed back and forth five times with a 1 kg brass weight from the folded top. In the peeling observation process, the toner was peeled off when the recording medium was expanded and bent. In the determination step, when the width of the toner peeling portion was 1 mm or more, it was determined as “not good” and less than 1 mm as “good”. When the determination result was “not good”, the above four steps were performed in the same manner except that the fixing temperature was further raised by 5 ° C. The fixing temperature range was 100 ° C. or higher and 200 ° C. or lower. The above four steps were repeated until a determination result of “good” was obtained. The lowest fixing temperature among the plurality of fixing temperatures at which the determination result was “good” was defined as the minimum fixing temperature.

(Measurement of maximum fixing temperature of toner)
The measurement of the high-temperature fixing temperature of the toner includes three steps (an image forming step, an image forming step for evaluation, and a determining step). In the image forming process, an image was formed on the recording medium under the same conditions as those for measuring the minimum fixing temperature of the toner. In the image forming process for evaluation, the recording medium for evaluation (paper, CC90, 90 g / m ² ) was passed through the fixing unit without a gap after the image formation. Specifically, the recording medium for evaluation was passed through the fixing unit on the second round of the heating roller, with the circumference of the heating roller on which the toner image was fixed as a reference (first round). The fixing unit includes a heating roller. In the determination step, the evaluation recording medium was visually observed to confirm the presence or absence of transfer of the toner image to the evaluation recording medium. The case where transfer of the toner image was not confirmed was determined as “good”, and the case where transfer of the toner image was confirmed was determined as “not good”. When the determination result was “good”, the above three steps were performed in the same manner except that the fixing temperature was further raised by 5 ° C. The above three steps were repeated until a determination result of “not good” was obtained. The highest fixing temperature among the plurality of fixing temperatures at which the determination result was “good” was defined as the maximum fixing temperature.

The toner fixability was evaluated based on the following criteria from the obtained minimum fixing temperature and maximum fixing temperature.
A (very good): The minimum fixing temperature was 145 ° C. or lower, and the maximum fixing temperature was 190 ° C. or higher.
○ (Good): The minimum fixing temperature was higher than 145 ° C. and 150 ° C. or lower, and the maximum fixing temperature was 185 ° C. or higher and lower than 190 ° C.
X (Poor): The minimum fixing temperature exceeded 150 ° C and / or the maximum fixing temperature was less than 185 ° C.

[Evaluation results]
Evaluation results of toners (A-1) to (A-4) (toners according to Examples 1 to 4) and toners (B-1) to (B-6) (toners of Comparative Examples 1 to 6) Table 2 shows (fixing property, charging stability, and heat resistance stability).

  Toners (A-1) to (A-4) (toners according to Examples 1 to 4) were toners having the configuration (1). Specifically, the toners according to Examples 1 to 6 contained a crystalline resin and an amorphous resin as binder resins. Further, as shown in Table 1, the toners according to Examples 1 to 6 have a first endothermic peak in the temperature range of 50 ° C. to 60 ° C. in the first temperature rising process, and the temperature range of 65 ° C. to 95 ° C. It had a second endothermic peak below. Further, the second endothermic process had a third endothermic peak at 65 ° C. or higher and 95 ° C. or lower, and no peak derived from the glass transition point at a temperature range of 10 ° C. or higher and 150 ° C. or lower.

  Toners (B-1) to (B-6) (toners according to Comparative Examples 1 to 6) were toners having no configuration (1). Specifically, as shown in Table 1, the toners of Comparative Examples 1 and 3 to 5 did not have the first endothermic peak in the temperature range of 50 ° C. or more and 60 ° C. or less in the first temperature raising process. The toners of Comparative Examples 2 and 5 did not have a third endothermic peak at 65 ° C. or more and 95 ° C. or less in the second temperature raising process. The toner according to Comparative Example 6 did not have a peak derived from the glass transition point in the temperature range of 10 ° C. or more and 150 ° C. or less in the second temperature raising process.

  As shown in Table 2, the toners according to Examples 1 to 4 were evaluated as “good” or “very good” in terms of evaluation results of fixability, charge stability, and heat-resistant storage stability. The toners according to Comparative Examples 1 to 6 were evaluated as x (bad) in at least one evaluation result among the evaluation results of fixability, charge stability, and heat resistant storage stability. It was shown that the toners according to Examples 1 to 4 have excellent fixing properties, excellent charging stability, and excellent heat-resistant storage stability as compared with the toners according to Comparative Examples 1 to 6.

  In addition, toners (A-3) to (A-4) (toners according to Examples 3 to 4) had the configuration (2). Specifically, as shown in Table 1, in the toners according to Examples 3 to 4, the endothermic amount ΔH1 of the first endothermic peak was 2.0 J / g or more. On the other hand, the toners (A-1) to (A-2) (toners according to Examples 1 and 2) did not have the configuration (2). Specifically, in the toners according to Examples 1 and 2, the endothermic amount ΔH1 of the first endothermic peak was less than 2.0 J / g.

  As shown in Table 2, the toners according to Examples 3 to 4 were evaluated as （(very good) in the evaluation results of charge stability and heat-resistant storage stability. In the toners according to Examples 1 and 2, the evaluation results of the charging stability and the heat resistant storage stability were all “good”.

  It was shown that the toners according to Examples 3 to 4 have excellent charging stability and excellent heat-resistant storage stability as compared with the toners according to Examples 1 and 2.

  Furthermore, the toner (A-4) (toner according to Example 4) had the configuration (3). Specifically, as shown in Table 1, the toner according to Example 4 has an endothermic amount ΔH1 of the first endothermic peak, an endothermic amount ΔH2 of the second endothermic peak, and an endothermic amount ΔH3 of the third endothermic peak. 1) was satisfied. On the other hand, toners (A-1) to (A-3) (toners according to Examples 1 to 3) did not have the configuration (3). Specifically, the toners according to Examples 1 to 3 did not satisfy the formula (1).

  As shown in Table 2, the toner according to Example 4 had an evaluation result of fixability of ◎ (very good). For the toners according to Examples 1 to 3, the evaluation result of fixability was “good”.

  It was shown that the toner according to Example 4 has excellent fixability as compared with the toners according to Examples 1 to 3.

  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 or a printer.

P1 first endothermic peak P2 second endothermic peak P3 third endothermic peak ΔH1 endothermic amount of first endothermic peak ΔH2 endothermic amount of second endothermic peak ΔH3 endothermic amount of third endothermic peak Tg glass transition point

Claims (5)

An electrostatic latent image developing toner comprising a binder resin and a release agent,
The binder resin includes a crystalline resin and an amorphous resin,
The differential calorimetric curve measured with a differential scanning calorimeter is
In the first temperature raising process, the first endothermic peak P1 has a temperature range of 50 ° C. to 60 ° C., and the second endothermic peak P2 has a temperature range of 65 ° C. to 95 ° C.
It has a third endothermic peak P3 in the temperature range of 65 ° C. or more and 95 ° C. or less in the second temperature raising process, and does not have a peak derived from the glass transition point in the temperature range of 10 ° C. or more and 150 ° C. or less,
The first temperature raising process is performed at a temperature raising rate of 10 ° C./min from the first temperature raising start temperature of 10 ° C. to the first temperature raising end temperature of 150 ° C.,
In the second temperature increase process, after the first temperature increase process, the first temperature increase end temperature of 150 ° C. is maintained for 2 minutes, and the first temperature increase end temperature of 150 ° C. is increased for the second time. The temperature is lowered to a temperature start temperature of 10 ° C. at a temperature decrease rate of 10 ° C./min, and the second temperature increase start temperature of 10 ° C. is held for 3 minutes, and then the second temperature increase start temperature from 10 ° C. to the end of the second temperature increase An electrostatic latent image developing toner that is executed at a temperature rising rate of 10 ° C./min up to a temperature of 150 ° C. The electrostatic latent image developing toner according to claim 1, wherein an endothermic amount ΔH1 of the first endothermic peak P1 satisfies the following formula (A).
ΔH1 ≧ 2.0 J / g (A) The endothermic amount ΔH1 of the first endothermic peak P1, the endothermic amount ΔH2 of the second endothermic peak P2, and the endothermic amount ΔH3 of the third endothermic peak P3 satisfy the following formula (B): The electrostatic latent image developing toner according to 1.
2.0 J / g ≦ ΔH 1 + ΔH 2 −ΔH 3 ≦ 6.0 J / g (B) The electrostatic latent image developing according to any one of claims 1 to 3, wherein the solubility parameter SP _C of the crystalline resin and the solubility parameter SP _A of the amorphous resin satisfy the following formula (C): toner.
| SP _C -SP _A | ≧ 0.4 (C) The crystalline resin is a crystalline polyester resin;
The electrostatic latent image developing toner according to claim 1, wherein the amorphous resin is an amorphous polyester resin.

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