JP6879100B2 - toner - Google Patents

Description

The present invention relates to toner, and particularly to toner for electrostatic latent image development.

Patent Document 1 discloses a technique for incorporating a non-crystalline polyester resin, a crystalline polyester resin, and a styrene-acrylic acid resin into toner particles.

Japanese Unexamined Patent Publication No. 2015-4722

However, it is difficult to provide a toner having excellent heat-resistant storage property, low-temperature fixability, and document offset resistance only by the technique disclosed in Patent Document 1. For example, in Patent Document 1, although the low-temperature fixability of the toner has been studied, the poor dispersion of the toner component (internal additive) has not been sufficiently studied.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a toner having excellent heat-resistant storage property, low-temperature fixability, and document offset resistance.

The toner according to the present invention contains a plurality of toner particles containing a non-crystalline polyester resin and a crystalline polyester resin. The toner particles further contain a styrene-acrylic acid-based resin. The crystalline polyester resin is a polymer of a monomer containing an alcohol monomer, a carboxylic acid monomer, an acrylic acid-based monomer, and a styrene-based monomer. The temperature of the toner having a storage elastic modulus of 1.0 × 10 ⁸ Pa is 55 ° C. or higher. Temperature of the toner of the storage modulus 1.0 × 10 ⁵ Pa is 80 ° C. or less. The dispersion diameter of the crystalline polyester resin in the toner particles is 100 nm or more and 500 nm or less. The heat absorption of the heat absorption peak derived from the crystallization site of the crystalline polyester resin, which is measured at the second temperature rise by the differential scanning calorimetry of the toner, is measured at the first temperature rise by the differential scanning calorimetry of the toner. It is 80% or more of the heat absorption peak of the heat absorption peak derived from the crystallization site of the crystalline polyester resin. The measurement conditions of the differential scanning calorimetry are a measurement range of 20 ° C. to 150 ° C., a temperature rising rate of 10 ° C./min, a temperature lowering rate of 100 ° C./min, and an interval of 10 minutes between the first and second times.

According to the present invention, it is possible to provide a toner having excellent heat storage resistance, low temperature fixability, and document offset resistance.

It is a graph which shows the endothermic curve measured at the time of the temperature rise of the 1st test of the differential scanning calorimetry about the toner which concerns on embodiment of this invention. It is a graph which shows the endothermic curve measured at the time of the temperature rise of the 2nd test of the differential scanning calorimetry about the toner which concerns on embodiment of this invention. It is a graph which shows the G'temperature dependence curve of the toner which concerns on embodiment of this invention.

An embodiment of the present invention will be described. The evaluation results (values indicating the shape or physical properties, etc.) of the powder (more specifically, the toner matrix particles, the external additive, the toner, etc.) are included in the powder unless otherwise specified. It is the number average of the values measured for a considerable number of particles.

Unless otherwise specified, the average particle size of powders is the average number of circle-equivalent diameters of primary particles (Haywood diameter: the diameter of a circle having the same area as the projected area of particles) measured using a microscope. The value. Unless otherwise specified, the measured value of the medium volume diameter (D ₅₀ ) of the powder is measured using a laser diffraction / scattering type particle size distribution measuring device (“LA-750” manufactured by HORIBA, Ltd.). It is the value that was calculated. Further, the measured values of the acid value and the hydroxyl value are the values measured according to "JIS (Japanese Industrial Standards) K0070-1992" unless otherwise specified. Further, the measured values of the number average molecular weight (Mn) and the mass average molecular weight (Mw) are values measured by gel permeation chromatography unless otherwise specified.

The chargeability means the chargeability in triboelectric charging, unless otherwise specified. The strength of positive charging (or the strength of negative charging) in triboelectric charging can be confirmed by a well-known charging train or the like.

The SP value (solubility parameter) is calculated according to the Fedors calculation method (RF Fedors, "Polymer Engineering and Science", 1974, Vol. 14, No. 2, p147-154), unless otherwise specified. (Unit: (cal / cm ³ ) ^1/2 , temperature: 25 ° C.). The SP value is represented by the formula “SP value = (E / V) ^1/2 ” (E: molecular aggregation energy [cal / mol], V: molecular volume [cm ³ / mol]).

Hereinafter, the compound and its derivative may be collectively referred to by adding "system" after the compound name. When the polymer name is represented by adding "system" after the compound name, it means that the repeating unit of the polymer is derived from the compound or its derivative. In addition, acrylic and methacrylic may be collectively referred to as "(meth) acrylic". In addition, acrylonitrile and methacrylonitrile may be collectively referred to as "(meth) acrylonitrile".

The toner according to this embodiment can be suitably used for developing an electrostatic latent image, for example, as a positively charged toner. The toner of this embodiment is a powder containing a plurality of toner particles (particles having a configuration described later). The toner may be used as a one-component developer. Alternatively, a two-component developer may be prepared by mixing the toner and the carrier using a mixing device (for example, a ball mill).

In order to form a high-quality image, it is preferable to use a ferrite carrier (specifically, a powder of ferrite particles) as a carrier. Further, in order to form a high-quality image for a long period of time, it is preferable to use magnetic carrier particles including a carrier core and a resin layer covering the carrier core. In order to impart magnetism to the carrier particles, the carrier core may be formed of a magnetic material (for example, a ferromagnetic substance such as ferrite), or the carrier core may be formed of a resin in which the magnetic particles are dispersed. Good. Further, the magnetic particles may be dispersed in the resin layer covering the carrier core. 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 with respect to 100 parts by mass of the carrier. The positively charged toner contained in the two-component developer is positively charged by friction with the carrier.

The toner according to this embodiment can be used for forming an image 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, the image forming unit (charging device and exposure device) of the electrophotographic apparatus forms an electrostatic latent image on the photoconductor (for example, the surface layer portion of the photoconductor drum) based on the image data. Subsequently, a developing device of an electrophotographic apparatus (specifically, a developing device in which a developer containing toner is set) supplies toner to the photoconductor to develop an electrostatic latent image formed on the photoconductor. The toner is charged by friction with a carrier, developing sleeve, or blade in the developing apparatus before being fed to the photoconductor. For example, positively charged toner is positively charged. In the developing process, toner (specifically, charged toner) on a developing sleeve (for example, the surface layer of a developing roller in a developing device) arranged in the vicinity of the photoconductor is supplied to the photoconductor, and the supplied toner is supplied. A toner image is formed on the photoconductor by adhering to the electrostatic latent image of the photoconductor. The consumed toner is replenished from the toner container containing the replenishing toner to the developing device.

In the subsequent transfer step, the transfer device of the electrophotographic apparatus transfers the toner image on the photoconductor to an intermediate transfer body (for example, a transfer belt), and then further transfers the toner image on the intermediate transfer body to a recording medium (for example, paper). Transfer to. After that, the fixing device of the electrophotographic apparatus (fixing method: nip fixing by a heating roller and a pressure roller) heats and pressurizes the toner 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 superimposing toner images of four colors of black, yellow, magenta, and cyan. After the transfer step, the toner remaining on the photoconductor is removed by a cleaning member (for example, a cleaning blade). The transfer method may be a direct transfer method in which the toner image on the photoconductor is directly transferred to a recording medium without going through an intermediate transfer body. Further, the fixing method may be a belt fixing method.

The toner according to this embodiment contains a plurality of toner particles. The toner particles may include an external additive. When the toner particles include an external additive, the toner particles include a toner mother particle and an external additive. The external additive adheres to the surface of the toner matrix particles. The toner mother particles contain a binder resin. If necessary, the toner mother particles may contain an internal additive (for example, at least one of a release agent, a colorant, a charge control agent, and a magnetic powder) in addition to the binder resin. If it is not necessary, the external additive may be omitted. When the external additive is omitted, the toner mother particles correspond to the toner particles.

The toner particles contained in the toner according to the present embodiment may be toner particles having no shell layer (hereinafter referred to as non-capsule toner particles) or toner particles having a shell layer (hereinafter referred to as capsule toner particles). It may be described as). In the capsule toner particles, the toner mother particles include a toner core and a shell layer formed on the surface of the toner core. The shell layer is substantially composed of resin. For example, by covering the toner core that melts at a low temperature with a shell layer having excellent heat resistance, it is possible to achieve both heat-resistant storage stability and low-temperature fixability of the toner. Additives may be dispersed in the resin constituting 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. The shell layer may be substantially composed of a thermosetting resin, may be substantially composed of a thermoplastic resin, or may contain both a thermoplastic resin and a thermosetting resin. ..

Non-capsule toner particles can be produced, for example, by a pulverization method or an agglutination method. These methods facilitate good dispersion of the internal additive in the binder resin of the non-capsule toner particles. Generally, toner is roughly classified into pulverized toner and polymerized toner (also called chemical toner). The toner obtained by the pulverization method belongs to the pulverized toner, and the toner obtained by the agglutination method belongs to the polymerized toner.

In one example of the pulverization method, first, a binder resin, a colorant, a charge control agent, and a mold release agent are mixed. Subsequently, the obtained mixture is melt-kneaded using a melt-kneading device (for example, a single-screw or twin-screw extruder). Subsequently, the obtained melt-kneaded product is crushed, and the obtained crushed product is classified. As a result, toner mother particles are obtained. When the pulverization method is used, toner matrix particles can often be produced more easily than when the agglutination method is used.

In one example of the aggregation method, first, these fine particles are aggregated to a desired particle size in an aqueous medium containing fine particles of a binder resin, fine particles of a release agent, fine particles of a charge control agent, and fine particles of a colorant. Let me. As a result, agglomerated particles containing a binder resin, a mold release agent, a charge control agent, and a colorant are formed. Subsequently, the obtained agglomerated particles are heated to coalesce the components contained in the agglomerated particles. As a result, toner mother particles having a desired particle size can be obtained.

When producing capsule toner particles, the method of forming the shell layer is arbitrary. For example, the shell layer may be formed by using any of the in-situ polymerization method, the in-liquid curing coating method, and the core selvation method.

The toner according to this embodiment is a toner for electrostatic latent image development having the following configuration (hereinafter, referred to as a basic configuration).

(Basic composition of toner)
The toner contains a plurality of toner particles containing a non-crystalline polyester resin and a crystalline polyester resin. The toner particles further contain a styrene-acrylic acid-based resin. The crystalline polyester resin is a polymer of a monomer (resin raw material) containing an alcohol monomer, a carboxylic acid monomer, an acrylic acid-based monomer, and a styrene-based monomer. Storage modulus 1.0 × 10 ⁸ Pa toner temperature (hereinafter, may be referred to as "melt initial temperature TM _A") is temperatures above 55 ℃. Storage modulus 1.0 × 10 ⁵ Pa toner temperature (hereinafter, may be referred to as "melting end temperature TM _B") is 80 ° C. or less. The dispersion diameter of the crystalline polyester resin in the toner particles is 100 nm or more and 500 nm or less. The heat absorption of the heat absorption peak derived from the crystallization site of the crystalline polyester resin, which is measured at the second temperature rise by the differential scanning calorimetry of the toner, is measured at the first temperature rise by the differential scanning calorimetry of the toner. It is 80% or more of the heat absorption amount of the heat absorption peak derived from the crystallinity site of the crystalline polyester resin. The measurement conditions for the differential scanning calorimetry are a measurement range of 20 ° C. to 150 ° C., a temperature rising rate of 10 ° C./min, a temperature lowering rate of 100 ° C./min, and an interval of 10 minutes between the first and second times.

Hereinafter, the storage elastic modulus temperature dependence curve (vertical axis: storage elastic modulus, horizontal axis: temperature) of the toner measured under the conditions of a temperature rise rate of 2 ° C./min and a frequency of 6.28 radians / second by a leometer is shown as ". It is described as "G'temperature dependence curve". In the above-mentioned basic configuration, the initial melting temperature TMB _A and the final melting temperature TMB _B are values measured from the G'temperature dependence curve, respectively. The method for measuring the G'temperature dependence curve is the same method as in the examples described later or an alternative method thereof.

In the above basic configuration, the dispersion diameter of the crystalline polyester resin in the toner particles is the average number of circle-equivalent diameters of the crystalline polyester resin domains in the cross-sectional image of the toner particles.

Generally, by incorporating a non-crystalline polyester resin into the toner particles, a toner having excellent heat-resistant storage stability can be obtained. However, it is difficult to obtain a toner having excellent heat-resistant storage property and low-temperature fixability.

As a method for obtaining a toner excellent in both heat-resistant storage property and low-temperature fixability, it is conceivable to include a crystalline polyester resin in the toner particles in addition to the non-crystalline polyester resin. However, unless the compatibility between the non-crystalline polyester resin contained in the toner particles and the crystalline polyester resin is high, the effect of the crystalline polyester resin (specifically, the effect of improving the low-temperature fixability of the toner) is small. In order to improve the low temperature fixability of the toner, it is preferable to sufficiently reduce the dispersion diameter (specifically, the domain diameter) of the crystalline polyester resin in the toner particles. However, if the non-crystalline polyester resin and the crystalline polyester resin are excessively compatible with each other in the toner particles, document offset is likely to occur. Document offset is a phenomenon in which after the toner is fixed on a recording medium by heating, the next recording medium is placed on the recording medium while the recording medium is still warm, so that the overlapping recording media stick to each other. In order to increase the printing speed (and thus the throughput) of the image forming apparatus, it is desirable to use a toner in which document offset is unlikely to occur.

In the above-mentioned basic configuration, the measurement conditions for differential scanning calorimetry are a measurement range of 20 ° C. to 150 ° C., a temperature rise rate of 10 ° C./min, a temperature decrease rate of 100 ° C./min, and an interval of 10 minutes between the first and second times. .. That is, after raising the temperature of the toner from 20 ° C. to 150 ° C. at a temperature raising rate of 10 ° C./min, the temperature raising / lowering test for lowering the temperature of the toner from 150 ° C. to 20 ° C. at a temperature lowering rate of 100 ° C. The second test is started after the first test is completed and the toner is allowed to stand for 10 minutes while maintaining the temperature of the toner at 20 ° C. An endothermic curve (vertical axis: heat flow, horizontal axis: temperature) can be obtained by such differential scanning calorimetry. When the toner contains a crystallized crystalline polyester resin, the heat absorption peak derived from the crystallized portion of the crystalline polyester resin may be described as "CPES heat absorption peak" in the heat absorption curve of the toner. Yes) appears. The endothermic amount of the CPES endothermic peak corresponds to the heat absorption amount associated with the dissolution of the crystallinized portion of the crystalline polyester resin, and can be obtained from the area of the CPES endothermic peak. Hereinafter, the endothermic amount of the CPES endothermic peak appearing in the heat absorption curve obtained at the time of raising the _{temperature in the first test is "ΔH 1} ", and the endothermic peak of the CPES endothermic peak appearing in the heat absorption curve obtained at the time of raising the temperature in the second test The amount of heat may be described _{as "ΔH 2".} Further, _{the value obtained by dividing ΔH 2} by ΔH ₁ may be described as “CPES crystallinity index”. In the differential scanning calorimetry of the toner, when all of the crystalline polyester resin melted by the temperature rise in the first test is crystallized again by the temperature decrease in the first test, it becomes _{“ΔH 2} = ΔH _1”. On the other hand, when at least a part of the melted crystalline polyester resin does not crystallize, ΔH ₂ becomes smaller than ΔH _1. A large CPES crystallinity index (ΔH ₂ / ΔH ₁ ) of the toner means that the crystalline polyester resin in the toner is easily crystallized.

The toner having the above-mentioned basic configuration satisfies the relationship of _{the formula “ΔH 2} ≧ 0.8 × ΔH _1”. This means that in the differential scanning calorimetry of the toner, most of the crystalline polyester resin melted by the temperature rise in the first test crystallized again by the temperature decrease in the first test. The temperature lowering rate of the differential scanning calorimetry is very fast, 100 ° C./min. The crystalline polyester resin that can crystallize even when the temperature is lowered at such a rate is the crystalline polyester resin in the above-mentioned basic configuration. That is, in the toner having the above-mentioned basic configuration, the toner particles contain a crystalline polyester resin that is easily crystallized. By crystallinizing the crystalline polyester resin in the toner particles, the compatibility between the non-crystalline polyester resin contained in the toner particles and the crystalline polyester resin becomes low, and the document offset is suppressed.

A crystalline polyester resin that is easily crystallized tends to be difficult to be compatible with a non-crystalline polyester resin. If the compatibility between the non-crystalline polyester resin and the crystalline polyester resin is insufficient, it becomes difficult to sufficiently reduce the dispersion diameter of the crystalline polyester resin in the toner particles. The inventor of the present application uses a monomer polymer containing an alcohol monomer, a carboxylic acid monomer, an acrylic acid-based monomer, and a styrene-based monomer as the crystalline polyester resin, and also uses a non-crystalline polyester resin and a crystalline polyester resin. In addition, by further incorporating a styrene-acrylic acid-based resin into the toner particles, we succeeded in sufficiently reducing the dispersion diameter of the crystalline polyester resin, which is easily crystallized, in the toner particles. The reason for this is that the styrene-acrylic acid-based resin is compatible with the crystalline polyester resin (specifically, a polymer of a monomer containing an alcohol monomer, a carboxylic acid monomer, an acrylic acid-based monomer, and a styrene-based monomer). Is considered to be. In the above-mentioned basic configuration, the difference (absolute value) between the SP value of the styrene-acrylic acid resin and the SP value of the crystalline polyester resin is the SP value of the non-crystalline polyester resin and the SP value of the crystalline polyester resin. It tends to be smaller than the difference (absolute value). It is considered that the presence of the crystalline polyester resin in the toner particles with a dispersion diameter that is sufficiently small and not too small (specifically, 100 nm or more and 500 nm or less) makes the toner have a sharp melt property.

Generally, as the dissolution of the toner progresses, the storage elastic modulus of the toner tends to decrease. In the basic configuration described above, the storage modulus of the toner is 1.0 × 10 ⁸ Pa means that the toner has begun to melt. In a toner having a sharp melt property, the storage elastic modulus of the toner tends to decrease sharply when the toner starts to melt. Also, the storage modulus of the toner is 1.0 × 10 ⁵ Pa means that dissolution of the toner is sufficiently advanced. Melt initial temperature TM _A (particularly, temperature of the toner storage modulus 1.0 × 10 ⁸ Pa) is too low, heat-resistant storage stability and resistance to document offset resistance of the toner tends to become insufficient. Melting end temperature TM _B (particularly, temperature of the toner storage modulus 1.0 × 10 ⁵ Pa) is too high, the low temperature fixability of the toner tends to become insufficient. Melt initial temperature TM _A is at temperatures above 55 ℃, and it is melting end temperature TM _B is 80 ° C. or less, in approximately temperatures above 55 ℃ 80 ° C. in a temperature range of the toner is started to melt, and the toner It means that the dissolution proceeds sufficiently. Further, when the toner fixed on the recording medium (specifically, the toner image) is allowed to stand in an environment of room temperature (for example, 25 ° C.) after the toner is fixed, the temperature of the toner drops rapidly to around 55 ° C. However, after that, the temperature of the toner tends to gradually decrease. When the melt initial temperature TM _A toner is temperatures above 55 ℃ after toner fixing quickly because the storage modulus of the toner is sufficiently large, so that the document offset is suppressed. To obtain a toner excellent in the heat-resistant storage stability and low-temperature fixability and document offset resistance is the storage modulus of the toner temperature 30 ° C. is 3.0 × 10 ⁸ Pa or more, the storage modulus 1.0 × It is particularly preferable that the temperature of the toner of 10 ⁸ Pa is 55 ° C. or higher and 60 ° C. or lower, and ^{the temperature of the toner having a storage elastic modulus of 1.0 × 10 5} Pa is 75 ° C. or higher and 80 ° C. or lower. In the low temperature region around 30 ° C., the storage elastic modulus of the toner tends to be substantially constant. The storage elastic modulus of the toner at a temperature of 30 ° C. corresponds to the storage elastic modulus of the toner before heating (during storage).

In order to set the initial melting temperature TM _A to 55 ° C. or higher and the final melting temperature TM _B to 80 ° C. or lower, the amount of crystalline polyester resin in the toner particles is determined to be non-crystalline polyester in the above-mentioned basic configuration. It is 10 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the resin, and the amount of the styrene-acrylic acid-based resin in the toner particles is 30 parts by mass or more and 50 parts by mass with respect to 100 parts by mass of the non-crystalline polyester resin. The following is particularly preferable. If the amount of the styrene-acrylic acid-based resin is too large, the dispersibility of the toner component (internal additive) deteriorates, and the sharp melt property of the toner tends to be insufficient (toners TB-1 and TB-, which will be described later). 7). Styrene - the amount of acrylic resin is too small, a styrene to reduce the dispersion diameter of the crystalline polyester resin - the action of acrylic acid-based resin is not sufficiently obtained, that the melting end temperature TM _B to 80 ° C. or less (See toners TB-3, TB-5, and TB-9 described later). If the amount of the crystalline polyester resin is too small, that the melting end temperature TM _B to 80 ° C. or less difficult (see Toner TB-2 and TB-4 will be described later). If the amount of the crystalline polyester resin is too large, a large amount of large crystalline polyester resin domains will be present in the toner particles, and the sharp melt property of the toner tends to be insufficient (toner TB-6 and later described later). See TB-8). Further, if the amount of the crystalline polyester resin is too large, the pulverizability of the toner tends to deteriorate.

In order to obtain a toner suitable for image formation, the SP value of the styrene-acrylic acid-based resin is smaller than the SP value of the crystalline polyester resin, and the SP value of the styrene-acrylic acid-based resin and the SP value of the crystalline polyester resin. The difference (absolute value) from the above is preferably smaller than the difference (absolute value) between the SP value of the non-crystalline polyester resin and the SP value of the crystalline polyester resin. In a particularly preferable example, the SP value of the non-crystalline polyester resin is 10.0 (cal / cm ³ ) ^1/2 or more and 11.0 (cal / cm ³ ) ^1/2 or less, and the SP value of the crystalline polyester resin is Is 9.2 (cal / cm ³ ) ^1/2 or more and 9.9 (cal / cm ³ ) ^1/2 or less, and the SP value of the styrene-acrylic acid resin is 9.0 (cal / cm ³ ) ^{1 / 2} or more and 9.7 (cal / cm ³ ) ^1/2 or less.

In order to suppress poor dispersion of the toner component (internal additive) in the pulverized toner, the non-crystalline polyester resin contains an aliphatic diol having 2 to 6 carbon atoms as an alcohol component, does not contain bisphenol, and is an acid. It is preferable that the crystalline polyester resin contains an aromatic dicarboxylic acid as a component and does not contain an aromatic monomer as an alcohol component or an acid component.

1 and 2 show endothermic curves (vertical axis: heat flow (DSC signal), horizontal axis: temperature) measured for an example of toner having the above-mentioned basic configuration using a differential scanning calorimeter, respectively. .. The measurement conditions are a temperature range of 20 ° C. to 150 ° C., a temperature rising rate of 10 ° C./min, a temperature lowering rate of 100 ° C./min, and an interval of 10 minutes between the first and second times. FIG. 1 shows the CPES endothermic peak in the endothermic curve measured at the time of temperature rise in the first test. FIG. 2 shows the CPES endothermic peak in the endothermic curve measured at the time of temperature rise in the second test.

From the area S1 of the endothermic peak of CPES shown in FIG. 1, ΔH _{1 of} the toner (specifically, the amount of endothermic peak of the CPES endothermic peak appearing in the heat absorption curve obtained at the time of temperature rise in the first test) can be obtained. Further, from the area S2 of the endothermic peak of CPES shown in FIG. 2, ΔH _{2 of} the toner (specifically, the amount of endothermic peak of the CPES endothermic peak appearing in the heat absorption curve obtained at the time of raising the temperature in the second test) can be obtained. ..

FIG. 3 shows a G'temperature-dependent curve (vertical axis: storage elastic modulus, horizontal axis: temperature) measured for an example of a toner having the above-mentioned basic configuration using a rheometer. Specifically, FIG. 3 shows the storage elastic modulus of the toner at each temperature under the condition of a frequency of 6.28 radians / second while raising the temperature of the toner at a constant rate (heating rate of 2 ° C./min) using a rheometer. This is the result of measuring the rate. In the G'temperature dependence curve shown in FIG. 3, the storage elastic modulus decreases as the toner temperature rises. As shown in FIG. 3, melt initial temperature TM _A (particularly, temperature of the toner storage modulus 1.0 × 10 ⁸ Pa) it is at temperatures above 55 ℃, melting end temperature TM _B (particularly, the storage modulus The temperature of the toner of 1.0 × 10 ⁵ Pa) is 80 ° C. or lower. That is, both the melt initial temperature TM _A and the melting end temperature TM _B is present in the temperature range of 80 ° C. 55 ° C. or higher. Also, the storage modulus of the toner temperature 30 ° C. was 3.0 × 10 ⁸ Pa. In the G'temperature dependence curve shown in FIG. 3, the storage elastic modulus of the toner is substantially constant in the low temperature region near 30 ° C.

In order to obtain a toner suitable for image formation, _{it is preferable that the volume median diameter (D 50} ) of the toner particles is 4 μm or more and 9 μm or less.

Next, the composition of the non-capsule toner particles will be described. More specifically, the toner matrix particles (binding resin and internal additive) and external additive will be described in order. In the capsule toner particles, the toner mother particles in the non-capsule toner particles shown below can be used as the toner core.

[Toner mother particles]
The toner mother particles contain a binder resin. Further, the toner mother particles may contain an internal additive (for example, a colorant, a mold release agent, a charge control agent, and a magnetic powder).

(Bundling resin)
In the toner mother particles, the binder resin generally occupies most of the components (for example, 85% by mass or more). Therefore, it is considered that the properties of the binder resin have a great influence on the properties of the entire toner matrix 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 matrix particles tend to be anionic, and when the binder resin has an amino group. , The toner matrix particles tend to be cationic.

In the toner having the above-mentioned basic configuration, the toner mother particles contain a crystalline polyester resin, a non-crystalline polyester resin, and a styrene-acrylic acid-based resin as a binder resin.

The polyester resin is obtained by polycondensing one or more kinds of polyhydric alcohols and one or more kinds of polyvalent carboxylic acids. However, in order to obtain the crystalline polyester resin defined in the above-mentioned basic configuration, it is necessary to polycondensate the acrylic acid-based monomer and the styrene-based monomer in addition to the alcohol and the carboxylic acid. As the alcohol for synthesizing the polyester resin, for example, a divalent alcohol (more specifically, an aliphatic diol, bisphenol, etc.) or a trihydric or higher alcohol as shown below can be preferably used. As the carboxylic acid for synthesizing the polyester resin, for example, a divalent carboxylic acid or a trivalent or higher carboxylic acid as shown below can be preferably used.

Preferable examples of aliphatic diols include diethylene glycol, triethylene glycol, neopentyl glycol, 1,2-propanediol, α, ω-alkanediol (more specifically, ethylene glycol, 1,3-propanediol, etc.). 1,4-Butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,12-dodecanediol, etc. ), 2-Buten-1,4-diol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, or polytetramethylene glycol.

Preferable examples of bisphenol include bisphenol A, hydrogenated bisphenol A, bisphenol A ethylene oxide adduct, or bisphenol A propylene oxide adduct.

Preferable examples of trihydric or higher alcohols are 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, trimethylolethane, or 1,3,5- Trihydroxymethylbenzene can be mentioned.

Preferable examples of the divalent carboxylic acid include aromatic dicarboxylic acids (more specifically, phthalic acids, terephthalic acids, isophthalic acids, etc.), α, ω-alcandicarboxylic acids (more specifically, malonic acids). , Succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, or 1,10-decandicarboxylic acid, etc.), unsaturated dicarboxylic acid (more specifically, maleic acid, fumaric acid, citraconic acid, itaconic acid, etc.) Alternatively, glutaconic acid or the like), or cycloalkandicarboxylic acid (more specifically, cyclohexanedicarboxylic acid or the like) can be mentioned.

Preferable examples of trivalent or higher valent carboxylic acids are 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1, 2,4-Butantricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxy-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) Examples include methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, or empole trimeric acid.

The styrene-acrylic acid-based resin is a copolymer of one or more types of styrene-based monomers and one or more types of acrylic acid-based monomers.

In order to synthesize the crystalline polyester resin and the styrene-acrylic acid-based resin contained in the toner matrix particles, for example, the styrene-based monomer and the acrylic acid-based monomer as shown below can be preferably used.

Preferable examples of styrene-based monomers include styrene, alkyl styrene (more specifically, α-methyl styrene, p-ethyl styrene, 4-tert-butyl styrene, etc.), p-hydroxystyrene, m-hydroxystyrene. , Halogenized styrene (more specifically, monochlorostyrene, dichlorostyrene, p-bromostyrene, 2,4,5-tribromostyrene, or 2,4,6-tribromostyrene, etc.).

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

In order to obtain a toner suitable for image formation, in the above-mentioned basic configuration, the non-crystalline polyester resin is composed of 1,2-propanediol, an aromatic dicarboxylic acid (for example, terephthalic acid) and a trivalent carboxylic acid (for example, for example). It is a polymer of a monomer (resin raw material) containing a trimellitic acid), and the crystalline polyester resin is α, ω-alcandiol (preferably α, ω-alcandiol having 4 or more and 10 or less carbon atoms). And a divalent carboxylic acid (preferably an unsaturated dicarboxylic acid having 4 or more and 10 or less carbon atoms), a styrene-based monomer (for example, styrene), and a (meth) acrylic acid alkyl ester (preferably having 2 or more and 8 carbon atoms in the ester portion). It is a polymer of a monomer (resin raw material) containing a methacrylic acid alkyl ester having the following alkyl group), and the styrene-acrylic acid-based resin is a styrene-based monomer (for example, styrene) and (meth) acrylate amino. Being a polymer of a monomer (resin raw material) containing an alkyl ester (more specifically, aminoethyl acrylate or 2- (dimethylamino) ethyl methacrylate, etc.) and a cross-linking agent (for example, divinylbenzene). Is particularly preferable.

As the above 1,2-propanediol for synthesizing a non-crystalline polyester resin (binding resin), a plant-derived 1,2-propanediol is particularly preferable. Plant-derived 1,2-propanediols can be produced, for example, by using chemical synthesis, fermentation methods, or a combination of these methods. In one example of a method for producing a plant-derived 1,2-propanediol, glycerin is obtained by hydrolyzing plant biomass containing saccharides such as glucose. Subsequently, a plant-derived 1,2-propanediol is obtained by reacting glycerin with hydrogen. As the vegetable biomass, for example, one or more vegetable oils and fats selected from the group consisting of soybean oil, palm oil, palm oil, castor oil, and coconut oil can be used. As a method for hydrolyzing plant biomass, a chemical method using an acid or a base may be adopted, a biological method using an enzyme or a microorganism may be adopted, or another method may be adopted. May be good.

(Colorant)
The toner mother particles may contain a colorant. As the colorant, a pigment or dye known according to the color of the toner can be used. In order to obtain a toner suitable for image formation, the amount of the colorant 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 mother particles may contain a black colorant. An example of a black colorant is carbon black. Further, the black colorant may be a colorant that has been adjusted to black by using a yellow colorant, a magenta colorant, and a cyan colorant.

The toner matrix particles 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. Bat yellow can be preferably used.

The magenta colorant is selected from the group consisting of, for example, 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 copper phthalocyanine compounds, anthraquinone compounds, and base dye lake compounds can be used. Examples of the cyan colorant 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 mother particles may contain a release agent. The release agent is used, for example, for the purpose of improving the fixability or offset resistance of the toner. In order to improve the fixability or offset resistance of the toner, the amount of the release agent 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.

The release agent includes, for example, low molecular weight polyethylene, low molecular weight polypropylene, polyolefin copolymer, polyolefin wax, microcrystallin wax, paraffin wax, or aliphatic hydrocarbon wax such as Fishertropsh wax; polyethylene oxide wax or a block thereof. Oxides of aliphatic hydrocarbon waxes such as copolymers; vegetable waxes such as candelilla wax, carnauba wax, wood wax, jojoba wax, or rice wax; animal waxes such as honey wax, lanolin, or whale wax. Waxes; Mineral waxes such as ozokelite, ceresin, or petrolatum; Waxes mainly composed of fatty acid esters such as montanic acid ester wax or caster wax; Part or all of fatty acid esters such as deoxidized carnauba wax Deoxidized wax can be preferably used. One type of release agent may be used alone, or a plurality of types of release agents may be used in combination.

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

By incorporating a negatively charged charge control agent (more specifically, an organometallic complex, a chelate compound, etc.) into the toner mother particles, the anionic property of the toner mother particles can be strengthened. Further, by incorporating a positively charged charge control agent (more specifically, pyridine, niglosin, quaternary ammonium salt, etc.) into the toner mother particles, the cationic properties of the toner mother particles can be strengthened. However, when sufficient chargeability of the toner is ensured, it is not necessary to include a charge control agent in the toner mother particles.

(Magnetic powder)
The toner mother particles may contain magnetic powder. Examples of the material of the magnetic powder include a ferromagnetic metal (more specifically, iron, cobalt, nickel, or an alloy containing one or more of these metals), and a ferromagnetic metal oxide (more specifically, Ferromagnetism, magnetite, chromium dioxide, etc.) or a material that has been subjected to a ferromagnetization treatment (more specifically, a carbon material to which ferromagnetism has been imparted by heat treatment, etc.) can be preferably used. One kind of magnetic powder may be used alone, or a plurality of kinds of magnetic powder may be used in combination.

[External agent]
An external additive (specifically, a powder containing a plurality of external additive particles) may be attached to the surface of the toner matrix particles. Unlike the internal additive, the external additive does not exist inside the toner matrix particles, but selectively exists only on the surface of the toner matrix particles (the surface layer portion of the toner particles). For example, by stirring the toner matrix particles (powder) and the external additive (powder) together, the external additive particles can be adhered to the surface of the toner matrix particles. The toner mother particles and the external additive particles do not chemically react with each other and are physically bonded rather than chemically. The strength of the bond between the toner mother particles and the external additive particles is determined by the stirring conditions (more specifically, the stirring time, the rotation speed of stirring, etc.), the particle size of the external additive particles, and the shape of the external additive particles. , And the surface condition of the external additive particles can be adjusted.

In order to fully exert the function of the external additive while suppressing the detachment of the external agent particles from the toner particles, the amount of the external additive (when using multiple types of external agent particles, they are used. The total amount of the external additive particles) 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 mother particles.

As the external additive particles, inorganic particles are preferable, and silica particles or particles of metal oxides (more specifically, alumina, titanium oxide, magnesium oxide, zinc oxide, strontium titanate, barium titanate, etc.) are preferable. Especially preferable. In order to improve the fluidity of the toner, it is preferable to use inorganic particles (powder) having an average number of primary particle diameters of 5 nm or more and 30 nm or less as the external additive particles. However, as the external additive particles, particles of an organic acid compound such as a fatty acid metal salt (more specifically, zinc stearate or the like) or resin particles may be used. Further, as the external additive particles, composite particles which are composites of a plurality of kinds of materials may be used. One kind of external additive particles may be used alone, or a plurality of kinds of external additive particles may be used in combination.

The external additive particles may be surface-treated. For example, when silica particles are used as the external additive particles, the surface of the silica particles may be imparted with hydrophobicity and / or positive chargeability by a surface treatment agent. Examples of the surface treatment agent include a coupling agent (more specifically, a silane coupling agent, a titanate coupling agent, an aluminate coupling agent, etc.), a silazane compound (for example, a chain silazane compound or a cyclic silazane compound). ) Or silicone oil (more specifically, dimethyl silicone oil or the like) can be preferably used. As the surface treatment agent, a silane coupling agent or a silazane compound is particularly preferable. Preferable examples of the silane coupling agent include silane compounds (more specifically, methyltrimethoxysilane, aminosilane, etc.). Preferable examples of the silazane compound include HMDS (hexamethyldisilazane). When the surface of the silica substrate (untreated silica particles) is treated with a surface treatment agent, a large number of hydroxyl groups (-OH) present on the surface of the silica substrate are partially or wholly derived from the surface treatment agent. Substituted for a functional group. As a result, silica particles having a functional group derived from the surface treatment agent (specifically, a functional group having a more hydrophobic and / or positively charged property than a hydroxyl group) on the surface can be obtained.

Examples of the present invention will be described. Table 1 shows the toners TA-1 to TA-6 and TB-1 to TB-9 (each positively charged toner) according to Examples or Comparative Examples.

In Table 1, regarding the crystalline polyester resin, "CPES-1" and "CPES-2" were the crystalline polyester resins CPES-1 and CPES-2 prepared by the methods described later, respectively.
In Table 1, regarding the styrene-acrylic acid-based resin, "SAc-1" and "SAc-2" were crosslinked styrene-acrylic acid-based resins SAc-1 and SAc-2 prepared by the methods described below, respectively. ..
“Amount (unit: parts by mass)” in Table 1 indicates a relative amount with respect to 100 parts by mass of the non-crystalline polyester resin.

Hereinafter, the manufacturing method, the evaluation method, and the evaluation result of the toners TA-1 to TA-6 and TB-1 to TB-9 will be described in order. In the evaluation in which an error occurs, a considerable number of measured values in which the error is sufficiently small are obtained, and the arithmetic mean of the obtained measured values is used as the evaluation value.

[Preparation of materials]
(Preparation method of non-crystalline polyester resin)
First, palm oil, which is a vegetable oil, was hydrolyzed to obtain glycerin. Specifically, palm oil and a 10 mass% sodium hydroxide aqueous solution in an amount twice the amount required for completely saponifying the palm oil were added to the reaction vessel. Subsequently, the contents of the container were heated to completely saponify palm oil (vegetable oil) at a temperature of 150 ° C. The glycerin aqueous solution was separated from the contents of the container after saponification, and the obtained glycerin aqueous solution was distilled. The distilled glycerin was treated with activated carbon to purify the glycerin.

Next, 200 g of ethylene glycol and 76 g of cupric nitrate trihydrate were added into a reaction vessel equipped with a reflux condenser. Subsequently, the container contents were stirred at a temperature of 80 ° C. for 2 hours, 52 g of tetraethoxysilane was added dropwise, and the container contents were further stirred at a temperature of 80 ° C. for 2 hours. Then, after dropping 18 g of water into the container, the contents of the container were stirred at a temperature of 80 ° C. for 3 hours to obtain a precipitate in the container. The obtained precipitate was dried at a temperature of 120 ° C. and then fired in air at a temperature of 400 ° C. for 2 hours to obtain a copper / silica catalyst (copper content: 50% by mass). _{An aqueous solution containing 29.8 mg of tetraammine platinum (II) nitrate [Pt (NH 3} ) ₄ (NO ₃ ) ₂ ] 29.8 mg was added to 3 g of the obtained copper / silica catalyst, and the mixture was dried by a rotary evaporator. The obtained solid is dried at a temperature of 120 ° C. and then fired in air at a temperature of 400 ° C. for 2 hours to obtain a copper-platinum / silica catalyst having a copper content of 50% by mass (mass ratio: Cu / Pt / Si = 50). /0.5/17) was obtained.

Subsequently, 2 g of the copper-platinum / silica catalyst obtained as described above and 200 g of glycerin (purified glycerin) obtained in the above procedure were added to an iron autoclave having a capacity of 500 mL with a stirrer, and the air in the autoclave was added. Was replaced with hydrogen. Subsequently, the temperature inside the autoclave was raised to 230 ° C., and while introducing hydrogen gas into the autoclave at a rate of 5 L / min _{, the autoclave was subjected to the conditions of hydrogen (H 2} ) atmosphere, pressure of 2 MPa, and temperature of 25 ° C. The material (liquid) inside was reacted for 7 hours to obtain a reaction product (liquid). The obtained reaction product was purified by a conventional method to obtain a plant-derived 1,2-propanediol.

A 4-necked flask with a capacity of 5 L equipped with a stirrer (“SM-104” sold by AS ONE Corporation), a nitrogen introduction tube, a thermocouple, a dehydration tube, and a rectification column was used as a reaction vessel. In this reaction vessel, 1142 g (alcohol component) of plant-derived 1,2-propanediol prepared as described above, 1743 g of terephthalic acid (carboxylic acid component), and 4 g of tin dioctanoate (II) (condensation catalyst). And added. While removing the water produced by the reaction, the contents of the container were reacted at a temperature of 230 ° C. for 15 hours under atmospheric pressure in a nitrogen atmosphere. Then, the pressure in the container was reduced to 8.3 kPa, and the contents of the container were reacted for another 1 hour under the conditions of a pressure of 8.3 kPa and a temperature of 230 ° C.

Subsequently, the pressure in the container was returned to atmospheric pressure, the temperature in the container was lowered to 180 ° C., and then 288 g of trimellitic anhydride was added into the container. Then, the temperature inside the container was raised to 210 ° C. at a rate of 10 ° C./hour. Subsequently, the contents of the container were reacted under atmospheric pressure at a temperature of 210 ° C. for another 10 hours. Subsequently, the pressure inside the container was reduced to 20 kPa, and the contents of the container were reacted for another 1 hour under the conditions of a pressure of 20 kPa and a temperature of 230 ° C. After completion of the reaction, the contents of the container were taken out and cooled. As a result, a non-crystalline polyester resin was obtained.

(Method for preparing crystalline polyester resin CPES-1)
990 g of 1,4-butanediol (alcohol component) and 242 g of 1,6-hexanediol in a 4-port flask with a capacity of 5 L equipped with a thermometer (thermocouple), dehydration tube, nitrogen introduction tube, and agitator. (Alcohol component), 1480 g of fumaric acid (acid component), and 2.5 g of 1,4-benzenediol were added. Subsequently, the flask contents were reacted at a temperature of 170 ° C. for 5 hours. Subsequently, the flask contents were reacted at a temperature of 210 ° C. for 1.5 hours. Subsequently, the contents of the flask were reacted for 1 hour under the conditions of a reduced pressure atmosphere (pressure 8 kPa) and a temperature of 210 ° C. Subsequently, the atmosphere was returned to the normal pressure atmosphere, and 69 g of styrene (styrene-acrylic acid-based component) and 54 g of n-butyl methacrylate (styrene-acrylic acid-based component) were placed in the flask. Subsequently, the flask contents were reacted at a temperature of 210 ° C. for 1.5 hours. Subsequently, the contents of the flask were reacted for 1 hour under the conditions of a reduced pressure atmosphere (pressure 8 kPa) and a temperature of 210 ° C. As a result, a crystalline polyester resin CPES-1 having an SP value of 9.9 (cal / cm ³ ) ^{1/2 was obtained.}

(Preparation method of crystalline polyester resin CPES-2)
In the above-mentioned "Method for preparing crystalline polyester resin CPES-1", the monomer composition ratio was changed to obtain crystalline polyester resin CPES-2 having ^{an SP value of 9.6 (cal / cm 3} ) ^1/2.

(Method for preparing crosslinked styrene-acrylic acid resin SAc-1)
In a reaction vessel equipped with a stirrer and a thermometer, 5058 g of ion-exchanged water, 14 g of sodium sulfate, and an antifoaming agent (polyoxyalkylene pentaerythritol ether: "Dishome (registered trademark) CE-457" manufactured by Nichiyu Co., Ltd. ) 60g was added. Subsequently, 6740 g of 2- (dimethylamino) ethyl methacrylate, 2136 g of styrene, 10 g of a cross-linking agent (divinylbenzene having a purity of 56.5%), 75 g of a polymerization initiator (BPO: benzoyl peroxide), and t-butyl 14 g of peroxy-2-ethylhexyl monocarbonate (“Trigonox® 117” manufactured by Kayaku Akzo Corporation) was added. The temperature of the contents of the container was 40 ° C. Subsequently, while stirring the contents of the container, the temperature of the contents of the container is raised from 40 ° C. to 130 ° C. over 65 minutes, and after the temperature of the contents of the container reaches 130 ° C., the contents of the container are further 2 hours. The product was reacted (specifically, a polymerization reaction). Then, the contents of the container were cooled to obtain a dispersion liquid of a crosslinked styrene-acrylic acid resin. The obtained dispersion was filtered (solid-liquid separated) with a metal mesh having an opening of 2 mm to obtain resin particles (powder). Subsequently, fine powder in the obtained resin particles (powder) was removed using a nylon filter cloth. Then, through a washing step and a drying step, a crosslinked styrene-acrylic acid resin SAc-1 having ^{an SP value of 9.6 (cal / cm 3} ) ^{1/2 was obtained.}

(Preparation method of crosslinked styrene-acrylic acid resin SAc-2)
In the above "Method for preparing crosslinked styrene-acrylic acid resin SAc-1", the monomer composition ratio was changed to change the SP value of 9.4 (cal / cm ³ ) ^1/2 of the crosslinked styrene-acrylic acid resin SAc-. I got 2.

[Toner manufacturing method]
(Preparation of toner matrix particles)
Using an FM mixer (“FM-20B” manufactured by Nippon Coke Industries Co., Ltd.), 100 parts by mass of a non-crystalline polyester resin (non-crystalline polyester resin obtained by the above procedure) and the types and amounts shown in Table 1 A crystalline polyester resin (either of the crystalline polyester resins CPES-1 and CPES-2 specified for each toner) and a crosslinked styrene-acrylic acid-based resin of the type and amount shown in Table 1 (specified for each toner). Cross-linked styrene-acrylic acid resin SAc-1 or SAc-2), 3 parts by mass of ester wax (“Nissan Electol® WEP-9” manufactured by Nichiyu Co., Ltd.), and carbon black (Mitsubishi). 5 parts by mass of "MA-100" manufactured by Kagaku Co., Ltd.) and 1 part by mass of a quaternary ammonium salt ("BONTRON (registered trademark) P-51" manufactured by Orient Chemical Co., Ltd.) were mixed. For example, in the production of the toner TA-1, 100 parts by mass of a non-crystalline polyester resin, 10 parts by mass of a crystalline polyester resin CPES-1, and 30 parts by mass of a crosslinked styrene-acrylic acid resin SAc-1 are used. 3 parts by mass of ester wax (Nissan Electol WEP-9), 5 parts by mass of carbon black (MA-100), and 1 part by mass of quaternary ammonium salt (BONTRON P-51) were mixed.

Subsequently, the obtained mixture was melt-kneaded using a twin-screw extruder (“PCM-30” manufactured by Ikegai Corp.). Then, the obtained kneaded product was cooled. Subsequently, the cooled kneaded product was roughly pulverized using a pulverizer (“Rotoplex (registered trademark)” manufactured by Hosokawa Micron Co., Ltd.). Subsequently, the obtained coarsely pulverized product was finely pulverized using a pulverizer (“Turbo Mill RS type” manufactured by Freund Turbo Co., Ltd.). Subsequently, the obtained finely pulverized product was classified using a classification machine (“Elbow Jet EJ-LABO type” manufactured by Nittetsu Mining Co., Ltd.). As a result, toner mother particles having a median volume diameter of 7 μm were obtained.

(External process)
Using an FM mixer (“FM-10B” manufactured by Nippon Coke Industries Co., Ltd.), under the conditions of a rotation speed of 3000 rpm and a jacket temperature of 20 ° C., 100 parts by mass of toner mother particles and silica fine particles (“AEROSIL” manufactured by Nippon Aerosil Co., Ltd.) Registered trademark) RA-200H ”, Contents: Dry silica particles surface-modified with trimethylsilyl group and amino group, number average primary particle size: about 12 nm) 1.2 parts by mass and conductive titanium oxide fine particles (Titanium Industry Co., Ltd.) "EC-100" manufactured by the company, substrate: TiO ₂ particles, coating layer: Sb-doped SnO ₂ layers, medium volume diameter: about 0.35 μm) 0.8 parts by mass were mixed for 2 minutes. As a result, the external additives (silica particles and titanium oxide particles) adhered to the surface of the toner mother particles. Then, sieving was performed using a sieve of 300 mesh (opening 48 μm). As a result, toners containing a large number of toner particles (toners TA-1 to TA-6 and TB-1 to TB-9) were obtained.

With respect to the toners TA-1 to TA-6 and TB-1 to TB-9 obtained as described above, the CPES dispersion diameter (specifically, the dispersion diameter of the crystalline polyester resin in the toner particles) and the storage elastic modulus. The measurement results of the temperature characteristics (initial melting temperature TM _A and final melting temperature TM _B ) and CPES crystallinity index (ΔH ₂ / ΔH ₁ ) are as shown in Table 2.

For example, with respect to the toner TA-1, a CPES dispersion diameter of 260 nm, melting the initial temperature TM _A (particularly, temperature of the toner storage modulus 1.0 × 10 ⁸ Pa) is the 58 ° C., the melting end temperature TM _B (particularly, temperature of the toner storage modulus 1.0 × 10 ⁵ Pa) is the 79 ° C., CPES crystalline index (ΔH ₂ / ΔH ₁₎ was 0.88 (= 88%) .. These measurement methods were as shown below.

<Measurement method of CPES dispersion diameter>
Toner (measurement target: any of toners TA-1 to TA-6 and TB-1 to TB-9) is dispersed in a room temperature curable epoxy resin and cured in an atmosphere at a temperature of 40 ° C. for 2 days to cure the cured product. Got Subsequently, the obtained cured product was stained with osmium tetroxide, and then cut out using an ultramicrotome equipped with a diamond knife (“EM UC6” manufactured by Leica Microsystems, Inc.), and a flaky sample having a thickness of 250 μm. Got Subsequently, the cross section of the obtained flaky sample (particularly, the cross section of the toner mother particle) was examined with a scanning electron microscope (“JSM-7401F” manufactured by JEOL Ltd., method: FE-SEM, FE electron source: conical FE. It was taken with an electron gun). Then, the dispersion diameter (circle equivalent diameter) of the crystalline polyester resin was measured by analyzing the SEM photographed image (cross-sectional image of the toner particles) using image analysis software (“WinROOF” manufactured by Mitani Shoji Co., Ltd.).

The number average dispersion diameter of the crystalline polyester resin domains in the cross section of the toner particles was measured. Specifically, the measured values of the dispersion diameters of 10 crystalline polyester resin domains are obtained for each cross-sectional image of one toner particle, and the crystallinity in the cross section of the toner particles is obtained based on the obtained 10 measured values. The number average dispersion diameter of the polyester resin domains was calculated. Further, for each of the 10 toner particles contained in the toner, the number average dispersion diameter of the crystalline polyester resin domains in the cross section of the toner particles was obtained, and the arithmetic mean of the obtained 10 measured values was used as the toner evaluation value ( CPES dispersion diameter).

<Measurement method of temperature characteristics of storage elastic modulus>
0.1 g of toner (measurement target: any of toners TA-1 to TA-6 and TB-1 to TB-9) is set in a pellet molding machine, and a load of 20 kN is applied to the toner at room temperature (about 25 ° C.) for 2 minutes. In addition, columnar pellets having a diameter of 10 mm and a thickness of 1 mm were obtained. Subsequently, the obtained pellets were set in the measuring device. A rheometer (“ARES” manufactured by TA Instruments Japan Co., Ltd.) was used as the measuring device. As the measuring plate, a circular parallel plate having a diameter of 10 mm was used. Then, the G'temperature dependence curve (vertical axis: storage elastic modulus, horizontal axis: temperature) of the toner was measured under the following conditions.

(Measurement condition)
Measurement temperature range: 50 ° C to 200 ° C
Temperature rise rate: 2 ° C / min Frequency: 6.28 radians / sec Measurement interval: 15 seconds Applied strain: Automatic measurement mode (initial value: 0.1%)
Stretch correction: Automatic measurement mode

From G 'temperature dependence curve obtained as described above, melt initial temperature TM _A (particularly, temperature of the toner storage modulus 1.0 × 10 ⁸ Pa) and melt end temperature TM _B (For details, It was read temperature) of the toner storage modulus 1.0 × 10 ⁵ Pa.

<Measurement method of _{ΔH 1} and ΔH _2>
As a measuring device, a TG-DSC system (“TAS-100” manufactured by Rigaku Co., Ltd.) was used. The endothermic curve of the toner (measurement target: any of toners TA-1 to TA-6 and TB-1 to TB-9) is measured by performing two elevating and lowering temperature tests using this measuring device. From the obtained endothermic curve, ΔH ₁ and ΔH ₂ of the toner were obtained. Specifically, 10 mg of toner was placed in an aluminum dish (aluminum container), and the aluminum dish was set in the measuring section of the measuring device. In the measurement of the endothermic curve, the temperature of the measurement unit was raised from the measurement start temperature of 20 ° C. to 150 ° C. at a rate of 10 ° C./min (RUN1). The endothermic curve (vertical axis: heat flow (DSC signal), horizontal axis: temperature) of the toner at the time of the first temperature rise was obtained by RUN1. Then, the temperature of the measuring part was lowered from 150 ° C. to 20 ° C. at a rate of 100 ° C./min. The temperature was kept at 20 ° C. for 10 minutes after the temperature reached 20 ° C. (interval between the first measurement and the second measurement). Subsequently, the temperature of the measuring unit was raised again from 20 ° C. to 150 ° C. at a rate of 10 ° C./min (RUN2). The endothermic curve (vertical axis: heat flow (DSC signal), horizontal axis: temperature) of the toner at the time of the second temperature rise was obtained by RUN2. From the endothermic curve of the toner at the time of the first temperature rise and the endothermic curve of the toner at the time of the second temperature rise obtained as described above, ΔH ₁ and ΔH _{2 of the} toner (respectively, at the crystallized portion of the crystalline polyester resin). The endothermic amount of the derived endothermic peak) was read. ΔH ₁ of the toner was obtained from the area of the endothermic peak of CPES in the endothermic curve of the toner at the time of the first temperature rise. ΔH ₂ of the toner was obtained from the area of the endothermic peak of CPES in the endothermic curve of the toner at the time of the second temperature rise. Then, ΔH ₂ was _{divided by ΔH 1} to obtain the CPES crystallinity index (ΔH ₂ / ΔH ₁ ) of the toner.

[Evaluation method]
The evaluation method of each sample (toner TA-1 to TA-6 and TB-1 to TB-9) is as follows.

(Heat storage)
2 g of toner (evaluation target: any of toners TA-1 to TA-6 and TB-1 to TB-9) is placed in a polyethylene container having a capacity of 20 mL, and the container is placed in a constant temperature bath set at a temperature of 60 ° C. It was allowed to stand inside for 3 hours. Then, the toner taken out from the constant temperature bath was cooled to room temperature (about 25 ° C.) to obtain an evaluation toner.

Subsequently, the obtained evaluation toner was placed on a sieve of 140 mesh (opening 105 μm) having a known mass. Then, the mass of the sieve containing the evaluation toner was measured, and the mass of the toner on the sieve (the mass of the toner before sieving) was determined. Subsequently, the above sieve is set in a powder property evaluation device (“Powder Tester (registered trademark)” manufactured by Hosokawa Micron Co., Ltd.), and the sieve is vibrated for 30 seconds under the condition of Leostud scale 5 according to the manual of the powder tester for evaluation. The toner was sieved. After sieving, the mass of toner remaining on the sieving without passing through the sieving (mass of toner after sieving) was measured. Then, the toner cohesion degree (unit: mass%) was determined according to the following formula based on the mass of the toner before sieving and the mass of the toner after sieving.
Toner cohesion = 100 x mass of toner after sieving / mass of toner before sieving

When the toner cohesion degree was 20% by mass or less, it was evaluated as ◯ (good), and when the toner cohesion degree was more than 20% by mass, it was evaluated as × (not good).

(Low temperature fixability)
Using a ball mill, 100 parts by mass of a carrier for a developing agent (carrier for FS-C5200DN) and 5 parts by mass of a toner (evaluation target: any of toners TA-1 to TA-6 and TB-1 to TB-9) are used. And mixed for 30 minutes to prepare a two-component developer.

As the evaluation machine, a printer having a Roller-Roller type heating and pressurizing type fixing device (an evaluation machine in which the fixing temperature can be changed by modifying "FS-C5200DN" manufactured by Kyocera Document Solutions Co., Ltd.) was used. The two-component developer prepared as described above is put into the developing apparatus of the evaluation machine, and the replenishing toner (evaluation target: any of toners TA-1 to TA-6 and TB-1 to TB-9) is evaluated. It was put into the toner container of the machine.

In an environment with a temperature of 23 ° C and a humidity of 50% RH, a linear speed of 105 mm / sec was applied to an evaluation sheet (Mondy's "ColorCopy (registered trademark)", A4 size, basis weight 90 g / m ^{2) using the above evaluation machine.} A black solid image (specifically, an unfixed toner image) having a size of 25 mm × 25 mm was formed under the condition of a toner loading amount of 1.3 mg / cm ^2. 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 measurement range of the fixing temperature was 100 ° C. or higher and 150 ° C. or lower. Specifically, the fixing temperature of the fixing device was lowered by 2 ° C. from 150 ° C. to determine whether or not fixing was possible for each fixing temperature, and the minimum temperature (minimum fixing temperature) at which a solid image (toner image) could be fixed to paper 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 crease was rubbed 5 times back and forth using a 1 kg brass weight covered with a cloth. .. Subsequently, the paper was unfolded and the bent portion of the paper (the portion where the solid image was formed) was observed. Then, the peeling length (peeling length) of the toner at the bent portion was measured. The lowest of 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 130 ° C. or lower, it was evaluated as ◯ (good), and when the minimum fixing temperature exceeded 130 ° C., it was evaluated as × (not good).

(Document offset)
Among the solid images formed in the evaluation of low temperature fixability, the document offset was evaluated for the solid image (toner image after fixing) fixed at the lowest fixing temperature (for example, 126 ° C. for toner TA-1). Specifically, two sheets of paper on which an image (toner image fixed at the lowest fixing temperature) was formed were overlapped in a state where the surfaces on which the image was formed were in contact with each other. The images formed on one piece of paper were overlaid so that they were in contact with both the image and non-image areas of the other paper. Then, the two stacked sheets of paper were placed on a table and a load was applied. ^{With a pressure of 16 g / cm 2} applied to the two stacked sheets of paper, the two sheets of paper were allowed to stand in an oven set at a temperature of 75 ° C. for 1 hour. Then, the two sheets of paper taken out of the oven were allowed to stand in a room temperature (about 25 ° C.) atmosphere for 30 minutes. Then, the two stacked sheets of paper were peeled off, the state of the image on each paper was confirmed, and the document offset was evaluated according to the following criteria.
◯ (Good): There was no image loss on either of the two sheets of paper.
X (not good): Image loss occurred on at least one of the two sheets of paper.

[Evaluation results]
The evaluation results for each sample (toners TA-1 to TA-6 and TB-1 to TB-9) are shown in Table 3. In Table 3, "L-fixing" means low-temperature fixing property, "preservation property" means heat-resistant storage property, and "DO" means document offset. The evaluation results shown in Table 3 are the minimum fixing temperature for low-temperature fixability, the degree of toner cohesion for heat-resistant storage, and the presence or absence of image defects (◯: none, ×: yes) for document offset.

Each of the toners TA-1 to TA-6 (toners according to Examples 1 to 6) had the above-mentioned basic configuration. Specifically, in the toners TA-1 to TA-6, the toner particles contained a non-crystalline polyester resin, a crystalline polyester resin, and a styrene-acrylic acid-based resin, respectively. The crystalline polyester resin is a polymer of a monomer containing an alcohol monomer, a carboxylic acid monomer, an acrylic acid-based monomer, and a styrene-based monomer (specifically, 1,4-butanediol, 1,6-hexanediol, and fumaric acid). (A polymer of styrene and n-butyl methacrylate) (see "Method for preparing crystalline polyester resin CPES-1" above). The initial melting temperature TM _A (specifically, the temperature of the toner having a storage elastic modulus of 1.0 × 10 ⁸ Pa) is 55 ° C. or higher, and the final melting temperature TM _B (specifically, the storage elastic modulus of 1.0 × 10 ⁵ Pa). Toner temperature) was 80 ° C. or lower (see Table 2). The dispersion diameter of the crystalline polyester resin in the toner particles was 100 nm or more and 500 nm or less (see Table 2). The CPES crystallinity index (ΔH ₂ / ΔH ₁ ) of the toner was 0.80 or more (see Table 2). That is, the heat absorption peak of the heat absorption peak derived from the crystallization site of the crystalline polyester resin, which is measured at the second temperature rise by the differential scanning calorimetry of the toner, is measured at the first temperature rise by the differential scanning calorimetry of the toner. It was 80% or more of the heat absorption peak of the heat absorption peak derived from the crystallinity site of the crystalline polyester resin.

As shown in Table 3, the toners TA-1 to TA-6 were excellent in heat-resistant storage property, low-temperature fixability, and document offset resistance.

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

Claims (6)

A toner containing a plurality of toner particles containing a non-crystalline polyester resin and a crystalline polyester resin.
The toner particles further contain a styrene-acrylic acid-based resin, and the toner particles are further contained.
The crystalline polyester resin is a polymer of a monomer containing an alcohol monomer, a carboxylic acid monomer, an acrylic acid-based monomer, and a styrene-based monomer.
The temperature of the toner having a storage elastic modulus of 1.0 × 10 ⁸ Pa is 55 ° C. or higher.
The temperature of the toner having a storage elastic modulus of 1.0 × 10 ⁵ Pa is 80 ° C. or lower.
The dispersion diameter of the crystalline polyester resin in the toner particles is 100 nm or more and 500 nm or less.
The amount of the crystalline polyester resin in the toner particles is 10 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the non-crystalline polyester resin.
The amount of the styrene-acrylic acid-based resin in the toner particles is 30 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the non-crystalline polyester resin.
The heat absorption of the heat absorption peak derived from the crystallization site of the crystalline polyester resin, which is measured at the second temperature rise by the differential scanning calorimetry of the toner, is measured at the first temperature rise by the differential scanning calorimetry of the toner. A toner having a heat absorption peak of 80% or more of the heat absorption peak derived from the crystallinized portion of the crystalline polyester resin.
[The measurement conditions of the differential scanning calorimetry are a measurement range of 20 ° C. to 150 ° C., a temperature rising rate of 10 ° C./min, a temperature lowering rate of 100 ° C./min, and an interval of 10 minutes between the first and second times. ] The storage modulus of the toner of the temperature 30 ° C. is at 3.0 × 10 ⁸ Pa or more,
The temperature of the toner having a storage elastic modulus of 1.0 × 10 ⁸ Pa is 55 ° C. or higher and 60 ° C. or lower.
The toner according to claim 1, wherein the temperature of the toner having a storage elastic modulus of 1.0 × 10 ⁵ Pa is 75 ° C. or higher and 80 ° C. or lower. The SP value of the styrene-acrylic acid resin is smaller than the SP value of the crystalline polyester resin.
The difference between the SP value of the styrene-acrylic acid resin and the SP value of the crystalline polyester resin is smaller than the difference between the SP value of the non-crystalline polyester resin and the SP value of the crystalline polyester resin. Item 1. The toner according to Item 1. The toner is a crushed toner and
The non-crystalline polyester resin contains an aliphatic diol having 2 to 6 carbon atoms as an alcohol component, does not contain bisphenol, and contains an aromatic dicarboxylic acid as an acid component.
The toner according to claim 1 or 3 , wherein the crystalline polyester resin does not contain an aromatic monomer as an alcohol component or an acid component. The non-crystalline polyester resin is a polymer of a monomer containing 1,2-propanediol, an aromatic dicarboxylic acid, and a trivalent carboxylic acid.
The crystalline polyester resin is a polymer of a monomer containing α, ω-alcandiol, a divalent carboxylic acid, a styrene-based monomer, and a (meth) acrylic acid alkyl ester.
The toner according to claim 1 or 3 , wherein the styrene-acrylic acid-based resin is a polymer of a monomer containing a styrene-based monomer, a (meth) acrylic acid aminoalkyl ester, and a cross-linking agent. The toner according to any one of claims 1 to 5 , which is a positively charged toner.

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