JP2019061207A - toner - Google Patents

Abstract

To provide a toner that is excellent in heat-resistant storage property, low-temperature fixability, and document offset resistance.SOLUTION: A toner particle contains a crystalline resin, a first amorphous resin, and a second amorphous resin. The absolute value of the difference between the SP value of the crystalline resin and the SP value of the first amorphous resin is larger than the absolute value of the difference between the SP value of the crystalline resin and the SP value of the second amorphous resin. In the temperature dependency curve of the storage elastic modulus (G') of the toner, the temperature at G'1.0×10Pa is 45°C or more; the temperature at G'2.0×10Pa is 60 to 80°C; the temperature at G'1.0×10Pa is 70 to 100°C; G' at a temperature 5°C lower than the temperature at G'1.0×10Pa is 5.0×10Pa or more; the maximum rate of change of G' in a second temperature area (G':1.0×10to 1.0×10Pa) is larger than the maximum rate of change of G' in a first temperature area G':1.0×10to 2.0×10Pa).SELECTED DRAWING: Figure 1

Description

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

In Patent Document 1, the storage elastic modulus G ′ at 100 ° C. at the temperature rising is 1 × 10 ³ to 1 × 10 ⁶ Pa, and the storage elastic modulus G ′ at 100 ° C. at the temperature falling is 1 × 10 ³ to 1 × 10 ^The toner is described which has ⁶ Pa and a storage elastic modulus G ′ at 100 ° C. is higher at temperature lowering than at temperature rising.

JP, 2017-009982, A

  However, it is difficult to provide a toner which is excellent in heat resistant storage stability, low temperature fixability, and document offset resistance only by the technique disclosed in Patent Document 1. Specifically, in consideration of storage of the toner in a high temperature and high humidity environment, it is difficult to ensure sufficient heat resistance storage stability of the toner.

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

The toner according to the present invention contains a plurality of toner particles containing a crystalline resin. The toner particles further contain a first noncrystalline resin and a second noncrystalline resin. The absolute value of the difference between the SP value of the crystalline resin and the SP value of the first non-crystalline resin is the absolute value of the difference between the SP value of the crystalline resin and the SP value of the second non-crystalline resin. Greater than. The storage elastic modulus temperature dependency curve of the toner measured while raising the temperature of the toner at a speed of 2 ° C./min changes the storage elastic modulus from 1.0 × 10 ⁸ Pa to 2.0 × 10 ⁶ Pa It has a first temperature range and a second temperature range in which the storage elastic modulus changes from 1.0 × 10 ⁶ Pa to 1.0 × 10 ⁵ Pa. In the storage elastic modulus temperature dependency curve, the temperature of storage elastic modulus 1.0 × 10 ⁸ Pa is 45 ° C. or higher, and the temperature of storage elastic modulus 2.0 × 10 ⁶ Pa is 60 ° C. or higher and 80 ° C. or lower ^{5. The} storage elastic modulus is 1.0 × 10 ⁵ Pa and the temperature is 70 ° C. to 100 ° C., and the storage elastic modulus is 5 ° C. lower than the temperature of the storage elastic modulus 1.0 × 10 ⁵ Pa. 0 × is at 10 ⁵ Pa or more, the maximum rate of change in storage modulus at the second temperature region is larger than the maximum rate of change in storage modulus at the first temperature region.

  According to the present invention, it is possible to provide a toner which is excellent in heat resistant storage stability, low temperature fixing property, and document offset resistance.

5 is a graph showing an example of a storage elastic modulus temperature dependency curve of a toner according to an embodiment of the present invention.

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

If the number average particle diameter of the powder is not specified at all, the number average particle diameter of the primary particles (Heywood diameter: diameter of a circle having the same area as the projected area of the particles) measured using a microscope It is a value. In addition, the measurement value of the volume median diameter (D ₅₀ ) of the powder is measured using a laser diffraction / scattering type particle size distribution measuring apparatus (“LA-750” manufactured by Horiba, Ltd.) unless otherwise specified. Value.

  The glass transition point (Tg) is a value measured according to “JIS (Japanese Industrial Standard) K 7 12 1-2012” using a differential scanning calorimeter (“DSC-6220” manufactured by Seiko Instruments Inc.) unless otherwise specified. It is. In the endothermic curve (vertical axis: heat flow (DSC signal), horizontal axis: temperature) measured with a differential scanning calorimeter, the temperature of the inflection point caused by the glass transition (specifically, the extrapolation line and falling of the baseline The temperature at the intersection point of the line with the extrapolation line corresponds to Tg (glass transition point). Further, the softening point (Tm) is a value measured using a Koka-type flow tester ("CFT-500D" manufactured by Shimadzu Corporation) unless otherwise specified. In the S-shaped curve (horizontal axis: temperature, vertical axis: stroke) measured by the heightening type flow tester, the temperature at which “(baseline stroke value + maximum stroke value) / 2” becomes Tm (softening point) Equivalent to.

  The term "main component" of a material means, unless otherwise specified, the component that is most abundant in the material on a mass basis. In addition, the chargeability means the chargeability in triboelectric charge, unless specified. The strength of positive chargeability (or the strength of negative chargeability) in the frictional charge can be confirmed by a known charge train or the like.

The SP value (solubility parameter) is calculated according to the Fedors calculation method (RF Fedors, “Polymer Engineering and Science”, 1974, Volume 14, No. 2, p 147-154) unless otherwise specified. It is a value (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 cohesive energy [cal / mol], V: molecular volume [cm ³ / mol]).

  Hereinafter, “system” may be added after the compound name to generically generically refer to the compound and its derivative. When a “system” is added after the compound name to represent a polymer name, it means that the repeating unit of the polymer is derived from the compound or its derivative.

  The toner according to the present embodiment can be suitably used, for example, as a positively chargeable toner for developing an electrostatic latent image. The toner of the present embodiment is a powder including a plurality of toner particles (particles each having a configuration to be described later). The toner may be used as a one-component developer. Alternatively, the 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 (more specifically, powder of ferrite particles) as a carrier. Moreover, in order to form a high quality image over 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 even if the carrier core is formed of a resin in which magnetic particles are dispersed. Good. In addition, magnetic particles may be dispersed in a resin layer that covers 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 chargeable toner contained in the two-component developer is positively charged by the friction with the carrier.

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

  First, an image forming unit (charging device and exposure device) of an electrophotographic apparatus forms an electrostatic latent image on a photosensitive member (for example, a surface layer portion of a photosensitive drum) based on image data. Subsequently, a developing device of the electrophotographic apparatus (specifically, a developing device filled with a developer containing toner) supplies toner to the photosensitive member to develop the electrostatic latent image formed on the photosensitive member. The toner is charged by friction with a carrier, a developing sleeve or a blade in the developing device before being supplied to the photosensitive member. For example, positively chargeable toner is positively charged. In the developing step, toner (specifically, charged toner) on a developing sleeve (for example, a surface layer portion of a developing roller in a developing device) disposed in the vicinity of the photosensitive member is supplied to the photosensitive member, and the supplied toner is By adhering to the electrostatic latent image of the photosensitive member, a toner image is formed on the photosensitive member. An amount of toner corresponding to the amount of toner consumed in the developing process is replenished from the toner container containing the replenishing toner to the developing device.

  In the subsequent transfer step, after the transfer device of the electrophotographic apparatus transfers the toner image on the photosensitive member to the intermediate transfer member (for example, transfer belt), the toner image on the intermediate transfer member is further used as a recording medium (for example, paper) Transfer to Thereafter, a fixing device (fixing method: nip fixing by a heating roller and a pressure roller) of the electrophotographic apparatus heats and presses 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 superposing four color toner images of black, yellow, magenta and cyan. After the transfer process, the toner remaining on the photosensitive member 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 photosensitive member is directly transferred to the recording medium without passing through the intermediate transfer member. The fixing method may be a belt fixing method.

  The toner according to the present embodiment includes a plurality of toner particles. The toner particles may be provided with an external additive. When the toner particles include an external additive, the toner particles include toner base particles and an external additive. The external additive adheres to the surface of the toner base particles. The toner base particles contain a binder resin. The toner base particles may optionally 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 necessary, external additives may be omitted. When the external additive is omitted, toner base particles correspond to toner particles.

  The toner particles contained in the toner according to the exemplary embodiment may be toner particles not having a shell layer (hereinafter, referred to as “non-capsulated toner particles”), or toner particles having a shell layer (hereinafter, “toner particles”). (Described as “capsule toner particles”). In the capsule toner particles, the toner base particles comprise a toner core and a shell layer formed on the surface of the toner core. The shell layer is substantially made of resin. For example, by covering the toner core that melts at a low temperature with a shell layer that is excellent in heat resistance, it is possible to achieve both heat resistance storage stability and low temperature fixability of the toner. The additive 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 composed substantially of a thermoplastic resin, or may contain both a thermoplastic resin and a thermosetting resin. .

  Non-encapsulated toner particles can be made by a grinding process. The pulverization method makes it easy to disperse the internal additive well in the binder resin of non-capsulated toner particles. Generally, toners are roughly classified into pulverized toners and polymerized toners (also called chemical toners). The toner obtained by the pulverization method belongs to the pulverized toner.

  In one example of the grinding method, first, a binder resin, a colorant, a charge control agent, and a release agent are mixed. Subsequently, the obtained mixture is melt-kneaded using a melt-kneading apparatus (for example, a single-screw or twin-screw extruder). Subsequently, the obtained melt-kneaded product is cooled and then crushed. Subsequently, the ground product obtained is classified. Thereby, toner base particles (powder) are obtained.

  When producing encapsulated toner particles, the method of forming the shell layer is optional. For example, the shell layer may be formed using any of in-situ polymerization method, in-liquid curing coating method, and coacervation method.

  The toner according to the present embodiment has the following configuration (hereinafter, referred to as “basic configuration”).

(Basic configuration of toner)
The toner includes a plurality of toner particles containing a crystalline resin, a first noncrystalline resin, and a second noncrystalline resin. The absolute value of the difference between the SP value of the crystalline resin and the SP value of the first noncrystalline resin is larger than the absolute value of the difference between the SP value of the crystalline resin and the SP value of the second noncrystalline resin. The storage elastic modulus temperature dependency curve (vertical axis: storage elastic modulus, horizontal axis: temperature) of the toner measured while raising the temperature of the toner at a speed of 2 ° C./min is 1.0 × 10 ⁸ Pa of the storage elastic modulus having a first temperature region which changes 2.0 × 10 ⁶ Pa, and a second temperature region storage modulus varies from 1.0 × 10 ⁶ Pa to 1.0 × 10 ⁵ Pa from. In the storage elastic modulus temperature dependency curve of the toner, the temperature of the storage elastic modulus of 1.0 × 10 ⁸ Pa is 45 ° C. or higher, and the temperature of the storage elastic modulus of 2.0 × 10 ⁶ Pa is 60 ° C. to 80 ° C. Or less, the temperature of storage elastic modulus 1.0 × 10 ⁵ Pa is 70 ° C. or higher and 100 ° C. or lower, and the storage elastic modulus of which temperature is 5 ° C. lower than the temperature of storage elastic modulus 1.0 × 10 ⁵ Pa is 5 .0 is a × 10 ⁵ Pa or more, the maximum rate of change in storage modulus in the second temperature region is larger than the maximum rate of change of the storage modulus at a first temperature region.

  Hereinafter, the storage elastic modulus may be described as “G ′”, and the storage elastic modulus temperature dependence curve may be described as “G ′ temperature dependence curve”. The rate of change of the storage elastic modulus is the amount of change (absolute value) of the storage elastic modulus per unit temperature increase, and does not become a negative value. The minimum value of the storage elastic modulus change rate is 0 (zero). The rate of change of the storage modulus corresponds to the slope of the G 'temperature dependence curve and is obtained by differentiating the G' temperature dependence curve by temperature. The rate of change of the storage elastic modulus may be a value obtained by differentiating the common logarithm log G 'of the storage elastic modulus at temperature T (i.e., Δlog G' / ΔT). A graph in which the vertical axis of the G 'temperature dependence curve is the common logarithm value of the storage elastic modulus (vertical axis: the common logarithm value of the storage elastic modulus, the horizontal axis: temperature) is described as "log G' temperature dependence curve" There is a case.

In addition, the absolute value of the difference between the SP value of the crystalline resin and the SP value of the first noncrystalline resin is “ΔSP ₁ ”, and the difference between the SP value of the crystalline resin and the SP value of the second noncrystalline resin The absolute value of may be described as “ΔSP ₂ ”, respectively. When the unit is omitted and the SP value is indicated, the unit of the SP value is “(cal / cm ³ ) ^1/2 ”.

  FIG. 1 shows an example of the G 'temperature dependency curve (vertical axis: storage modulus, horizontal axis: temperature) of the toner having the above-described basic configuration. FIG. 1 shows the temperature dependency of the storage elastic modulus of the toner in the temperature range of 40 ° C. or more and 200 ° C. or less. More specifically, FIG. 1 shows the storage elastic modulus of the toner at each temperature under a frequency of 1 Hz while raising the temperature of the toner from 40 ° C. at a constant rate (heating rate 2 ° C./min) using a rheometer. It is the result of measurement. In the G 'temperature dependency curve shown in FIG. 1, the storage elastic modulus decreases as the temperature of the toner increases.

The G 'temperature dependency curve shown in FIG. 1 has a first temperature range R1 where the storage modulus changes from 1.0 × 10 ⁸ Pa to 2.0 × 10 ⁶ Pa, and a storage modulus of 1.0 × 10 6 ^And a second temperature range R2 that changes from ⁶ Pa to 1.0 × 10 ⁵ Pa. In the G 'temperature dependency curve shown in FIG. 1, the temperature T _A of the storage modulus of 1.0 × 10 ⁸ Pa is about 50 ° C., and the temperature T _B of the storage modulus of 2.0 × 10 ⁶ Pa is about 70 And a storage modulus of 1.0 × 10 ⁵ Pa, a temperature T _D of about 80 ° C. The temperature T _{C which} is 5 ° C. lower than the temperature T _{D of the} storage elastic modulus 1.0 × 10 ⁵ Pa is about 75 ° C. The storage modulus at temperature T _C is about 1.0 × 10 ⁶ Pa.

  Two shoulders S1 and S2 exist in the temperature range of 40 ° C. to 200 ° C. in the G ′ temperature dependence curve shown in FIG. The temperature of the shoulder S1 is about 50.degree. The temperature of the shoulder S2 is about 75 ° C. Hereinafter, a shoulder present in a region of a temperature of 60 ° C. or higher is referred to as a “high temperature shoulder”, and a shoulder present in a region of a temperature below 60 ° C. is referred to as a “low temperature shoulder”. The shoulder S1 corresponds to a low temperature shoulder, and the shoulder S2 corresponds to a high temperature shoulder. At each temperature of the shoulders S1 and S2, the rate of change of the storage elastic modulus of the toner (corresponding to the slope of the G 'temperature dependence curve) changes rapidly. In the G 'temperature dependency curve, if it is not possible to clearly determine the point (point) where the slope changes sharply, the tangent of the curve before the slope changes sharply and the slope after the steep change The point of intersection with the tangent of the curve is taken as the shoulder.

  In the G 'temperature dependency curve shown in FIG. 1, two stable temperature ranges C1 and C2 exist in the temperature range of 40 ° C. or more and 200 ° C. or less. The storage elastic modulus is substantially constant in each temperature range of the stable temperature range C1 and C2.

  When the temperature of the toner is raised at a constant speed from 40 ° C., the storage elastic modulus of the toner does not substantially change until the temperature of the toner exceeds the stable temperature range C1. When the temperature of the toner rises and the temperature of the toner reaches the temperature of the shoulder S1, the storage elastic modulus of the toner starts to decrease sharply, and after the storage elastic modulus of the toner decreases at a large change rate for a certain period of time When the rate of change gradually decreases and reaches the stable temperature region C2, the storage elastic modulus of the toner does not substantially change. After that, when the temperature of the toner reaches the temperature of the shoulder S2, the storage elastic modulus of the toner starts to decrease sharply again, and after the storage elastic modulus of the toner decreases at a large change rate for a certain period, the change rate gradually It becomes smaller.

In the toner having the characteristics shown in FIG. 1, the temperature T _A of the storage modulus 1.0 × 10 ⁸ Pa is not less 45 ° C. or higher, the temperature T _B of the storage modulus 2.0 × 10 ⁶ Pa is 60 ° C. or higher 80 ° C. or less, temperature T _{D of} storage elastic modulus 1.0 × 10 ⁵ Pa is 70 ° C. or more and 100 ° C. or less, temperature T 5 lower than temperature T _{D of} storage elastic modulus 1.0 × 10 ⁵ Pa The storage modulus of the storage modulus of _C is 5.0 × 10 ⁵ Pa or more, and the maximum rate of change of the storage modulus in the second temperature range R2 is from the maximum rate of change of the storage modulus in the first temperature range R1. Too big. Such toners are excellent in heat resistant storage stability, low temperature fixability, and document offset resistance. Document offset is a phenomenon in which, after the toner is fixed to the recording medium by heating, the next recording medium is placed on the recording medium while it is still warm, and the overlapping recording medium is stuck. When the fixing temperature of the toner is high, the temperature difference with the outside air is large, so that the cooling speed of the toner becomes fast. Therefore, when the fixing temperature of the toner is high, document offset hardly occurs. On the other hand, when the fixing temperature of the toner is low, the cooling rate of the toner becomes slow, and thus document offset tends to occur. Therefore, it is difficult to suppress the occurrence of document offset while enabling low-temperature fixing of toner. However, the inventor of the present invention succeeded in obtaining a toner excellent in heat-resistant storage stability, low-temperature fixability, and document offset resistance by the two-step G ′ temperature dependence curve as shown in FIG.

  In the toner having the characteristics shown in FIG. 1, the storage elastic modulus of the toner is sufficiently high in the temperature range (for example, 25 ° C. or more and 45 ° C. or less) at the time of toner storage. Such toners have excellent heat resistant storage stability.

Moreover, although it is lower than the above 1.0 × 10 ⁸ Pa, the storage elastic modulus (specifically, 2.0 × 10 ⁶ Pa) is high enough to sufficiently suppress the occurrence of document offset. The temperature is in a temperature range of 60 ° C. or more and 80 ° C. or less. These toners have excellent document offset resistance because the storage modulus of the toner is sufficiently high in the temperature range where document offset tends to occur (specifically, about 60 ° C.).

In addition, since the storage elastic modulus of the toner is a sufficiently low value (specifically, 2.0 × 10 ⁶ Pa) in the temperature range of 60 ° C. to 80 ° C., it is easy to ensure sufficient low temperature fixability of the toner. Become. Further, as the maximum change rate of the storage elastic modulus in the second temperature region R2 is larger, the low temperature fixability of the toner tends to be improved. For this reason, it is preferable that the maximum change rate of the storage elastic modulus in the second temperature range R2 is larger than the maximum change rate of the storage elastic modulus in the first temperature range R1. When the rate of change of the storage elastic modulus is represented by Δlog G ′ / ΔT (specifically, the value obtained by differentiating the common logarithm log G ′ of the storage elastic modulus by the temperature T), the maximum change of the storage elastic modulus in the first temperature range R1 Rate (ie, the maximum value of Δlog G ′ / ΔT in the first temperature range R1) is 0.03 or more and 0.10 or less, and the maximum change rate of the storage elastic modulus in the second temperature range R2 (ie, the second temperature range It is particularly preferable that the maximum value of Δlog G ′ / ΔT in R 2 be 0.15 or more and 0.60 or less.

The inventor of the present invention makes a toner particle contain a crystalline resin, a first noncrystalline resin and a second noncrystalline resin, and ΔSP ₁ (specifically, the SP value of the crystalline resin and the first noncrystalline resin) By setting the absolute value of the difference between the SP value and the SP value of ΔSP ₂ (in detail, the absolute value of the difference between the SP value of the crystalline resin and the SP value of the second noncrystalline resin) It succeeded in obtaining the toner which has composition.

When ΔSP ₂ is smaller than ΔSP ₁ , the second non-crystalline resin can be compatible with the crystalline resin. Forming a first shoulder (for example, a shoulder S1 as shown in FIG. 1) in the vicinity of the glass transition point of the second noncrystalline resin by compatibilizing the crystalline resin and the second noncrystalline resin. Can. When the crystalline resin and the second non-crystalline resin are compatible, the crystalline resin functions as a plasticizer. For this reason, the substantial glass transition temperature of the second non-crystalline resin is lower than the glass transition point when the second non-crystalline resin is present alone. The position and inclination of the first shoulder also change depending on the degree of compatibility between the crystalline resin and the second noncrystalline resin.

In addition, since ΔSP ₂ is smaller than ΔSP ₁ , the second noncrystalline resin is compatible with the crystalline resin, while the crystalline resin and the first noncrystalline resin are in an incompatible state. Can. Due to the high crystallinity of the incompatible crystalline resin present in the first non-crystalline resin, the second shoulder (eg, a shoulder S2 as shown in FIG. 1) is obtained in the vicinity of the softening point of the crystalline resin. Can be formed. In addition, the position and inclination of a 2nd shoulder change also with the compatibility degree of crystalline resin and 1st non-crystalline resin.

In order to obtain a toner excellent in heat-resistant storage stability, low temperature fixability, and document offset resistance, the temperature range of temperature ± 10 ° C. of storage elastic modulus 1.0 × 10 ⁸ Pa in the G ′ temperature dependency curve of the toner (for details, "storage temperature -10 ° C. elastic modulus 1.0 × 10 ⁸ Pa" more or less "temperature + 10 ° C. storage modulus 1.0 × 10 ⁸ Pa") first shoulder is present, the storage elastic rate 1.0 × 10 ⁶ temperature range of temperature ± 10 ℃ of Pa (See "temperature of the storage modulus 1.0 × 10 ⁶ Pa -10 ℃" or "storage modulus 1.0 × 10 ⁶ Pa It is particularly preferred that a second shoulder is present at a temperature of + 10 ° C. or less). In addition, the G 'temperature dependency curve of the toner maintains the storage elastic modulus in the range of 6.0 × 10 ⁶ Pa or more and 6.3 × 10 ⁶ Pa or less between the first shoulder and the second shoulder. It is particularly preferable to have a third temperature range (for example, a stable temperature range C2 as shown in FIG. 1) and the width of the third temperature range to be 10.degree. C. or more.

  For example, by using a crystalline resin having a sufficiently high softening point, lowering the softening point of the first non-crystalline resin, and raising the softening point of the second non-crystalline resin, it is appropriate for appropriate position The slope can form a first shoulder and a second shoulder. Making the slope of the second shoulder larger than the slope of the first shoulder makes the maximum rate of change of the storage elastic modulus in the second temperature range greater than the maximum rate of change of the storage elastic modulus in the first temperature range it can. However, if the ratio of the amount of the second noncrystalline resin to the amount of the first noncrystalline resin is too large, the first shoulder and / or the second shoulder may not be formed. For example, if the amount of the first non-crystalline resin is too low, the first shoulder may not be formed. Also, if the amount of the second non-crystalline resin is too large, the second shoulder may not be formed. In addition, when the softening point of the crystalline resin is too low, it is difficult to sufficiently reduce the maximum change rate of the storage elastic modulus in the first temperature range. In addition, when the softening point of the crystalline resin is too low, it is difficult to sufficiently increase the maximum change rate of the storage elastic modulus in the second temperature range. The reason is considered to be that most of the noncrystalline resin is melted in the first temperature range, and the amount of the noncrystalline resin which is melted in the second temperature range is reduced. In addition, if the softening point of the crystalline resin is too low, it becomes difficult to sufficiently increase the melting start temperature of the toner (for example, the temperature of the first shoulder).

  In order to obtain a toner excellent in heat resistant storage stability, low temperature fixability, and document offset resistance, the glass transition point of each of the first noncrystalline resin and the second noncrystalline resin is 48 ° C. in the above-described basic configuration. It is particularly preferable that the temperature is 60 ° C. or less and the softening point of the crystalline resin is 80 ° C. or more and 100 ° C. or less.

In order to make the maximum change rate of the storage elastic modulus in the second temperature range larger than the maximum change rate of the storage elastic modulus in the first temperature range, ΔSP ₁ (specifically, the SP value of the crystalline resin and the first non The absolute value of the difference from the SP value of the crystalline resin) is 1.2 (cal / cm ³ ) ^1/2 or more, and ΔSP ₂ (specifically, the SP value of the crystalline resin and the second noncrystalline resin The absolute value of the difference from the SP value) is preferably 1.0 (cal / cm ³ ) ^1/2 or less. In addition, in order to cause the first and second shoulders to be present at appropriate positions, ΔSP ₁ is 1.2 (cal / cm ³ ) ^1/2 or more and 1.3 (cal / cm ³ ) ^1/2 or less. It is particularly preferable that ΔSP ₂ be 0.5 (cal / cm ³ ) ^1/2 or more and 1.0 (cal / cm ³ ) ^1/2 or less. The absolute value of the difference between the SP value of the first noncrystalline resin and the SP value of the second noncrystalline resin is 0.2 (cal / cm ³ ) ^1/2 or more and 2.0 (cal / cm ³⁾ ) is preferably ^1/2 or less, particularly preferably 0.3 (cal / cm ^{3) 1/2} or more 1.0 (cal / cm ^{3) 1/2} or less. In a preferred example of the toner, the SP value of the first noncrystalline resin is larger than the SP value of the second noncrystalline resin, and the SP value of the crystalline resin is smaller than the SP value of the second noncrystalline resin. However, the SP value of the crystalline resin may be between the SP value of the first noncrystalline resin and the SP value of the second noncrystalline resin.

  In order to obtain a toner suitable for image formation, the non-crystalline polyester resin having a glass transition temperature of 48 ° C. to 60 ° C. and a softening point of 80 ° C. to 90 ° C. in the above-described basic configuration. And the second non-crystalline resin is a non-crystalline polyester resin having a glass transition temperature of 48 ° C. to 60 ° C. and a softening point of 120 ° C. to 150 ° C., and a crystalline resin having a softening point of 80 ° C. to 100 ° C. The following crystalline polyester resins are particularly preferred.

  When the toner including the first noncrystalline resin, the second noncrystalline resin, and the crystalline resin as described above is a pulverized toner, the mass of the first noncrystalline resin is the second noncrystalline resin. It is particularly preferable that the weight is 1 to 8 times the mass of The melt-kneaded product containing the first noncrystalline resin and the second noncrystalline resin in such a proportion tends to be excellent in uniformity and grindability. In addition, when the toner particles contain the first non-crystalline resin and the second non-crystalline resin in the proportion as described above, the first shoulder and the second shoulder are easily formed at appropriate positions. When the ratio of the amount of the second noncrystalline resin to the amount of the first noncrystalline resin is too large, it is difficult to sufficiently increase the maximum change rate of the storage elastic modulus in the second temperature region (toner described later See TB-3 and TB-4).

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

  Next, the configuration of non-capsulated toner particles is described. In detail, toner base particles (binder resin and internal additive) and an external additive will be described in order. In encapsulated toner particles, toner base particles in non-encapsulated toner particles shown below can be used as a toner core.

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

(Binder resin)
In general, the binder resin is the main component of the toner. In a preferred example of the magnetic toner containing magnetic powder, the binder resin accounts for about 60% by mass of the toner base particles. In a preferred example of nonmagnetic toner containing no magnetic powder, the binder resin accounts for about 85% by mass of the toner base particles. For this reason, it is considered that the properties of the binder resin greatly affect the properties of the entire toner matrix particles. By using a plurality of resins in combination as the binder resin, the properties of the binder resin (more specifically, the hydroxyl value, acid value, Tg, Tm, etc.) can be adjusted. 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 when the binder resin has an amino group, the toner The mother particles are more likely to be cationic.

  In the toner having the basic configuration described above, the toner base particles contain, as a binder resin, a crystalline resin, a first noncrystalline resin, and a second noncrystalline resin. In order to improve the low temperature fixability of the toner, it is particularly preferable that the crystalline resin, the first noncrystalline resin and the second noncrystalline resin are each polyester resins.

  The polyester resin is obtained by condensation polymerization of one or more polyhydric alcohols and one or more polyhydric carboxylic acids. As an alcohol for synthesizing a polyester resin, for example, a dihydric alcohol (more specifically, an aliphatic diol or a bisphenol etc.) or an alcohol having a trivalent or higher can be suitably used as shown below. As a carboxylic acid for synthesizing a polyester resin, for example, a divalent carboxylic acid or a trivalent or higher carboxylic acid as shown below can be suitably used.

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

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

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

  Preferred examples of the divalent carboxylic acid include aromatic dicarboxylic acids (more specifically, phthalic acid, terephthalic acid, or isophthalic acid etc.), α, ω-alkanedicarboxylic acids (more specifically, malonic acid) Succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid or 1,10-decanedicarboxylic acid, etc., unsaturated dicarboxylic acid (more specifically, maleic acid, fumaric acid, citraconic acid, itaconic acid, Or glutaconic acid and the like) or cycloalkane dicarboxylic acid (more specifically, cyclohexane dicarboxylic acid and the like).

  Preferred examples of trivalent or higher carboxylic acids include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra (methylene carboxyl) Methane, 1,2,7,8-octane tetracarboxylic acid, pyromellitic acid, or Empol trimer acid can be mentioned.

  Preferable examples of the non-crystalline polyester resin having a glass transition temperature of 48 ° C. to 60 ° C. and a softening point of 80 ° C. to 90 ° C. include bisphenol (eg, bisphenol A ethylene oxide adduct and / or bisphenol A) as an alcohol component. And propylene oxide adducts), and containing an aromatic dicarboxylic acid (eg, terephthalic acid) and / or an α, ω-alkanedicarboxylic acid (eg, adipic acid) as an acid component, and containing no trivalent or higher carboxylic acid Noncrystalline polyester resins are mentioned.

  As a preferable example of the non-crystalline polyester resin having a glass transition temperature of 48 ° C. to 60 ° C. and a softening point of 120 ° C. to 150 ° C., bisphenol (eg, bisphenol A ethylene oxide adduct and / or bisphenol A) as an alcohol component And propylene oxide adduct), and as an acid component, an aromatic dicarboxylic acid (for example, terephthalic acid) and / or an α, ω-alkanedicarboxylic acid (for example, adipic acid), and a trivalent or higher carboxylic acid (for example, tri) (Non-crystalline polyester resin) containing

  Preferred examples of crystalline polyester resins having a softening point of 80 ° C. to 100 ° C. include α, ω-alkanediols (preferably, α, ω-alkanediols having 2 to 8 carbon atoms) and unsaturated dicarboxylic acids (preferably α, ω-alkanediols). Preferably, a polymer of a monomer (resin raw material) containing an unsaturated dicarboxylic acid having 4 or more and 10 or less carbon atoms is mentioned. Moreover, the monomer (resin raw material) of this example may further contain an α, ω-alkanedicarboxylic acid (preferably, an α, ω-alkanediol having 8 to 12 carbon atoms). As a suitable example of (alpha), (omega)-alkanediol, a 4-carbon 1, 4- butanediol is mentioned. As a suitable example of unsaturated dicarboxylic acid, C4 fumaric acid is mentioned. As a suitable example of (alpha), (omega)-alkanedicarboxylic acid, the carbon number 10 sebacic acid is mentioned.

(Colorant)
The toner mother particles may contain a colorant. As the colorant, known pigments or dyes may be used in accordance with the color of the toner. 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. Examples of black colorants include carbon black. The black colorant may be a colorant toned to black using a yellow colorant, a magenta colorant, and a cyan colorant.

  The toner matrix particles may contain color colorants such as yellow colorants, magenta colorants, or cyan colorants.

  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 yellow colorants include C.I. I. Pigment yellow (3, 12, 13, 14, 15, 17, 62, 74, 83, 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 suitably used.

  The magenta colorant is selected, for example, from the group consisting of condensation 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 magenta colorants include C.I. I. Pigment red (2, 3, 5, 6, 7, 19, 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 suitably used.

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

(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 the offset resistance of the toner. In order to improve the fixing property or the 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.

  As a mold release agent, for example, 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 block thereof Oxides of aliphatic hydrocarbon waxes such as copolymers; vegetable waxes such as candelilla wax, carnauba wax, wax wax, jojoba wax, or rice wax; animal nature such as bees wax, lanolin or wax wax Waxes; mineral waxes such as ozokerite, ceresin, or petrolatum; waxes based on fatty acid esters such as montanic acid ester wax or castor wax; fatty acids such as deacidified carnauba wax The wax portion of the ester or the whole was deoxygenated can be suitably used. One type of release agent may be used alone, or two or more 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 indicator of whether or not the toner can be charged to a predetermined charge level in a short time.

  By incorporating a negatively chargeable charge control agent (more specifically, an organic metal complex, a chelate compound or the like) in the toner base particles, the anionic property of the toner base particles can be enhanced. In addition, the cationic property of the toner base particles can be enhanced by containing the charge control agent (more specifically, pyridine, nigrosine, quaternary ammonium salt or the like) having positive chargeability in the toner base particles. However, when sufficient chargeability is ensured in the toner, the toner base particles do not need to contain a charge control agent.

(Magnetic powder)
The toner base particles may contain magnetic powder. The material of the magnetic powder includes, for example, ferromagnetic metals (more specifically, iron, cobalt, nickel, alloys containing one or more of these metals, etc.), ferromagnetic metal oxides (more specifically, Ferrite, magnetite, or chromium dioxide or the like, or a material subjected to a ferromagnetic treatment (more specifically, a carbon material or the like to which ferromagnetism is imparted by heat treatment) can be suitably used. One type of magnetic powder may be used alone, or two or more types of magnetic powder may be used in combination.

[External additive]
An external additive (more specifically, a powder containing a plurality of external additive particles) may be attached to the surface of the toner base particles. Unlike the internal additive, the external additive is not present inside the toner base particles, and selectively present only on the surface of the toner base particles (the surface layer of the toner particles). For example, the external additive particles can be attached to the surface of the toner base particles by stirring the toner base particles (powder) and the external additive (powder) together. The toner base particles and the external additive particles do not chemically react with each other and physically but not chemically. The bonding strength between the toner base particles and the external additive particles is determined by stirring conditions (more specifically, stirring time, rotational speed of stirring, etc.), particle diameter of external additive particles, shape of external additive particles And the surface condition of the external additive particles.

  In order to sufficiently exhibit the function of the external additive while suppressing the detachment of the external additive particle from the toner particles, the amount of the external additive (when using plural types of external additive particles, they may be used. The total amount of 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 toner base particles.

  As external additive particles, inorganic particles are preferable, and particles of silica particles or metal oxides (more specifically, particles of alumina, titanium oxide, magnesium oxide, zinc oxide, strontium titanate, barium titanate, etc.) Particularly preferred. In order to improve the flowability of the toner, it is preferable to use inorganic particles (powder) having a number average primary particle diameter of 5 nm to 30 nm as 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 etc.) or resin particles may be used. Also, as the external additive particles, composite particles which are composites of plural kinds of materials may be used. One type of external additive particle may be used alone, or two or more types of external additive particle 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 treatment agent may impart hydrophobicity and / or positive chargeability to the surface of the silica particles. As the surface treatment agent, for example, a coupling agent (more specifically, a silane coupling agent, a titanate coupling agent, or 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 etc.) can be suitably used. As a surface treatment agent, a silane coupling agent or a silazane compound is particularly preferable. Preferred examples of the silane coupling agent include silane compounds (more specifically, methyltrimethoxysilane or aminosilane, etc.). Preferred examples of silazane compounds include HMDS (hexamethyldisilazane). When the surface of a 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 entirely derived from the surface treatment agent It is substituted by a functional group. As a result, silica particles having a functional group derived from the surface treatment agent (specifically, a functional group that is more hydrophobic and / or more positively charged than a hydroxyl group) can be obtained.

  An embodiment of the present invention will be described. Table 1 shows toners TA-1 to TA-2 and TB-1 to TB-5 (positively chargeable toners) according to Examples or Comparative Examples.

  In Table 1, "APES-1" to "APES-4" respectively mean non-crystalline polyester resins APES-1 to APES-4 shown in Table 2. In Table 1, "CPES-1" to "CPES-6" mean crystalline polyester resins CPES-1 to CPES-6 shown in Table 3, respectively. The unit of "amount" in Table 1 is parts by mass.

In Table 1, ΔSP ₁ (specifically, the absolute value of the difference between the SP value of binder resin A and the SP value of binder resin C) and ΔSP ₂ (specifically, the SP value of binder resin B and binder resin The unit of each absolute value of the difference with the SP value of C is "(cal / cm ³ ) ^1/2 ".

  Hereinafter, a method of manufacturing toners TA-1 to TA-2 and TB-1 to TB-5, an evaluation method, and an evaluation result will be described in order. In addition, in the evaluation which an error produces, the measurement value of a considerable number which an error becomes small enough was obtained, and the arithmetic mean of the obtained measurement value was made into the evaluation value.

[Method of producing toner]
(Preparation of toner base particles)
Binder resins A to C of the types and amounts shown in Table 1 (however, only binder resins A and B in the production of toner TB-5) and coloring using an FM mixer (manufactured by Japan Coke Industry Co., Ltd.) Agent (component: copper phthalocyanine pigment, color index: pigment blue 15: 3) 5 parts by mass and ester wax (NOF Corporation "Nissan Electol (registered trademark) WEP-3") 5 parts by mass were mixed . For example, in the production of toner TA-1, 80 parts by mass of non-crystalline polyester resin APES-1, 10 parts by mass of non-crystalline polyester resin APES-2, and 10 parts by mass of crystalline polyester resin CPES-1 Then, 5 parts by mass of an ester wax (Nissan Electol WEP-3) and 5 parts by mass of a colorant (copper phthalocyanine pigment) were mixed.

  Subsequently, the obtained mixture was melt-kneaded using a twin-screw extruder ("PCM-30" manufactured by Ikegai Co., Ltd.). Thereafter, the obtained kneaded product was cooled. Subsequently, the cooled kneaded material was roughly pulverized using a pulverizer (formerly "Rotoplex 16/8" manufactured by Toa Machinery Co., Ltd.). Subsequently, the obtained coarsely pulverized material was pulverized using a pulverizer ("Turbo Mill RS type" manufactured by Freund Turbo Co., Ltd.). Subsequently, the obtained pulverized material was classified using a classifier ("Elbow Jet EJ-LABO type" manufactured by Nittetsu Mining Co., Ltd.). As a result, toner base particles (powder) having a volume median diameter of 7 μm were obtained.

(External addition process)
100 parts by mass of toner base particles and positively chargeable silica particles (manufactured by Nippon Aerosil Co., Ltd.) using an FM mixer ("FM-10B" manufactured by Japan Coke Industry Co., Ltd.) at a rotational speed of 3000 rpm and a jacket temperature of 20 ° C "AEROSIL (registered trademark) RA-200H", Content: Dry silica particles surface-modified with trimethylsilyl and amino groups, number average primary particle size: about 12 parts by mass, and conductive titanium oxide fine particles ( Titanium industrial product "EC-100", base material: TiO ₂ particles, coating layer: Sb-doped SnO ₂ layer, volume median diameter: about 0.35 μm) 0.8 parts by mass were mixed for 5 minutes. As a result, the external additive (silica particles and titanium oxide particles) adheres to the surface of the toner base particles. Then, it sifted using the sieve of 300 mesh (48 micrometers of openings). As a result, toners (toners TA-1 to TA-2 and TB-1 to TB-5) containing a large number of toner particles were obtained.

  The dynamic viscoelasticity of each of the toners TA-1 to TA-2 and TB-1 to TB-5 obtained as described above is shown in Table 4.

In Table 4, "T _A " corresponds to a temperature of storage elastic modulus of 1.0 × 10 ⁸ Pa, and "T _B " corresponds to a temperature of storage elastic modulus of 2.0 × 10 ⁶ Pa, "T _D ′ ′ corresponds to a temperature of storage modulus of 1.0 × 10 ⁵ Pa. Also, “T _C ” corresponds to a temperature 5 ° C. lower than the temperature T _D of the storage elastic modulus of 1.0 × 10 ⁵ Pa. Table 4 shows the storage modulus at a temperature T _C (= T _D −5 ° C.). The “first temperature range” corresponds to a temperature range in which the storage elastic modulus of the toner changes from 1.0 × 10 ⁸ Pa to 2.0 × 10 ⁶ Pa by raising the temperature of the toner. The “temperature range” corresponds to a temperature range in which the storage elastic modulus of the toner changes from 1.0 × 10 ⁶ Pa to 1.0 × 10 ⁵ Pa by raising the temperature of the toner. Table 4 shows the maximum change rate of the storage elastic modulus in each temperature range. The rate of change of the storage elastic modulus is a value obtained by differentiating the common logarithm log G 'of the storage elastic modulus with temperature T (that is, Δlog G' / ΔT).

For example, for toner TA-1, the temperature T _A is 54.5 ° C., the temperature T _B is 75.0 ° C., the temperature T _D is 79.0 ° C., and the storage elastic modulus of the temperature T _C is a 2.9 × 10 ⁶ Pa, the maximum rate of change in storage modulus in the first temperature region is 0.08, the maximum rate of change in storage modulus in the second temperature range was 0.40. The temperatures T _A , T _B , and T _D and the storage elastic modulus of the temperature T _C were obtained from the G ′ temperature dependency curve of the toner, respectively. Further, the maximum change rate of the storage elastic modulus in each of the first temperature range and the second temperature range was obtained from the log G 'temperature dependency curve of the toner. The measurement method of each of the G ′ temperature dependence curve and the log G ′ temperature dependence curve of the toner was as follows.

0.1 g of toner (target of measurement: any of toners TA-1 to TA-2 and TB-1 to TB-5) is set in a pellet molding machine, pressure is applied to the toner, and the diameter is 10 mm and the thickness is 1 mm. A cylindrical pellet was obtained. Subsequently, the obtained pellet was set in a measuring device. As a measuring device, a rheometer ("Physica MCR-301" manufactured by Anton Paar Co., Ltd.) was used. A measuring jig (parallel plate) was attached to the tip of the shaft of the measuring device (specifically, a motor driven shaft). The pellet was placed on the plate of the measuring device (specifically, a heating table heated by a heater). The pellet on the plate was heated to 110 ° C. to melt the pellet (toner mass) once. When the entire toner melted, the measuring jig (parallel plate) was brought into close contact with the melted toner from above, and the toner was sandwiched between two parallel plates (upper: measuring jig, lower: heat stand) . Then, the toner was cooled to 40.degree. Subsequently, using the measurement device, the G 'temperature dependency curve (vertical axis: toner) under the conditions of a measurement temperature range of 40 ° C. to 200 ° C., a temperature raising rate of 2 ° C./min, a vibration frequency of 1 Hz and a strain of 1% Measure storage elastic modulus, horizontal axis: temperature) and obtain logG 'temperature dependence curve (vertical axis: common logarithm of storage elastic modulus, horizontal axis: temperature) based on the measured G' temperature dependence curve The Then, the G 'temperature dependence curve of the toner, and the temperature T _A of the storage modulus 1.0 × 10 ⁸ Pa, and the temperature T _B of the storage modulus 2.0 × 10 ⁶ Pa, the storage modulus 1.0 The temperature T _D of x 10 ⁵ Pa and the storage modulus of the temperature T _C (= T _D- 5 ° C), which is 5 ° C. lower than the temperature T _D , were read. Further, by differentiating the log G 'temperature dependency curve of the toner with temperature, a differential curve showing the magnitude of the slope of the log G' temperature dependency curve (that is, the rate of change of the storage elastic modulus) at each temperature was obtained. From the obtained differential curve, the first temperature range (specifically, the temperature range in which the storage elastic modulus changes from 1.0 × 10 ⁸ Pa to 2.0 × 10 ⁶ Pa) and the second temperature range (specifically, the storage) The maximum change rate of the storage elastic modulus in each temperature region in which the elastic modulus changes from 1.0 × 10 ⁶ Pa to 1.0 × 10 ⁵ Pa was determined.

[Evaluation method]
The evaluation method of each sample (toner TA-1 to TA-2 and TB-1 to TB-5) is as follows.

(Heat resistant storage stability)
2 g of toner (object of evaluation: any of toners TA-1 to TA-2 and TB-1 to TB-5) is placed in a 20 mL polyethylene container, and the container is set to a temperature of 45 ° C. It was left standing for 3 hours. Thereafter, the toner removed from the thermostat was cooled to room temperature (about 25 ° C.) to obtain a toner for evaluation.

Subsequently, the obtained evaluation toner was placed on a 200-mesh (75 μm mesh) sieve of known weight. 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 screening) was determined. Subsequently, the sieve is set in a powder property evaluation apparatus ("powder tester (registered trademark)" manufactured by Hosokawa Micron Corporation), and the sieve is vibrated for 30 seconds under the condition of the rheostat graduation 5 according to the powder tester manual. The toner was sieved. After sieving, the mass of the toner remaining on the sieve without passing through the sieve (the mass of the toner after sieving) was measured. Then, based on the mass of the toner before screening and the mass of the toner after screening, the toner aggregation degree (unit: mass%) was determined according to the following equation.
Toner cohesion degree = 100 × mass of toner after sieving / mass of toner before sieving

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

(Low temperature fixability)
100 parts by mass of developer carrier (carrier for FS-C 5250 DN) and 5 parts by mass of toner (object of evaluation: any of toners TA-1 to TA-2 and TB-1 to TB-5) using a ball mill The mixture was mixed for 30 minutes to prepare a two-component developer.

  As an evaluation machine, a printer having a roller-roller type heat and pressure fixing device (an evaluation machine capable of changing the fixing temperature by modifying “FS-C5250 DN” manufactured by Kyocera Document Solutions Inc.) was used. The two-component developer prepared as described above is loaded into the developing device of the evaluation machine, and the replenishment toner (evaluation target: any of toners TA-1 to TA-2 and TB-1 to TB-5) is evaluated. Into the machine's toner container.

A linear velocity of 200 mm / sec on an evaluation sheet ("ColorCopy (registered trademark)" manufactured by Mondi, A4 size, 90 g / m ² basis weight) using the above-mentioned evaluation machine under an environment of temperature 23 ° C. and humidity 50% RH. A solid image (specifically, an unfixed toner image) of 25 mm × 25 mm in size was formed under the condition of a toner application amount of 1.0 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 lowest fixing temperature, the range of the fixing temperature was 80 ° C. or more and 180 ° C. or less. More specifically, while the fixing temperature of the fixing device was raised from 80 ° C. to 2 ° C. at each fixing temperature, the possibility of fixing was determined, and the minimum temperature (minimum fixing temperature) at which the solid image (toner image) could be fixed on 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 image-formed side was inside, and the image on the fold was rubbed back and forth five times using a 1 kg brass weight coated with fabric. . Subsequently, the paper was unfolded, and the folded part of the paper (the part 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 temperature of the fixing temperatures at which the peeling length is 1 mm or less was taken as the lowest fixing temperature. When the lowest fixing temperature was 140 ° C. or lower, it was evaluated as ○ (good), and when the lowest fixing temperature exceeded 140 ° C., it was evaluated as × (not good).

(Document offset)
The document offset was evaluated for the solid image (toner image after fixing) fixed at the lowest fixing temperature (for example, 132 ° C. for toner TA-1) among the solid images formed in the low temperature fixing evaluation. Specifically, two sheets of paper on which an image (toner image fixed at the lowest fixing temperature) was formed were superimposed in a state in which the surface on which the image was formed was in contact. Then, 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 70 ° C. for one hour. Thereafter, the two sheets of paper removed from the oven were allowed to stand in a room temperature (about 25 ° C.) atmosphere for 30 minutes. Thereafter, the two overlapping sheets of paper were peeled off to confirm the state of the image of each sheet, and the document offset was evaluated according to the following criteria.
○ (Good): The images of the two sheets of paper did not adhere to each other, and it was possible to easily separate the two sheets of paper.
((Normal): The images of the two sheets of paper are attached to each other, and when the two sheets of paper are pulled off, a sound (more specifically, a sound of crispness) was heard, but the image is lost on either of the two sheets of paper Did not occur.
X (not good): The images of two sheets of paper were attached to each other, and the image loss occurred in at least one of the two sheets of paper by peeling off the two sheets of paper.

[Evaluation results]
The evaluation results for each sample (toner TA-1 to TA-2 and TB-1 to TB-5) are shown in Table 5. “D.O.” in Table 5 means document offset. The evaluation results shown in Table 5 are the minimum fixing temperature for low temperature fixability and the toner aggregation degree for heat resistant storage stability. Also, D. O. As for (document offset), the evaluation result based on the above-mentioned criteria (o, Δ, and x) is shown.

The toners TA-1 to TA-2 (toners according to Examples 1 and 2) each had the above-described basic configuration. Specifically, the toners TA-1 to TA-2 are respectively a crystalline resin (specifically, crystalline polyester resin CPES-1 or CPES-2) and a first non-crystalline resin (specifically, non-crystalline polyester resin APES) A plurality of toner particles containing C-1) and a second non-crystalline resin (specifically, non-crystalline polyester resin APES-2) were contained. ΔSP ₁ (specifically, the absolute value of the difference between the SP value of the crystalline resin and the SP value of the first non-crystalline resin) is ΔSP ₂ (specifically, the SP value of the crystalline resin and the second non-crystalline resin) It was larger than the absolute value of the difference from the SP value (see Table 1). In the storage elastic modulus temperature dependency curve (vertical axis: storage elastic modulus, horizontal axis: temperature) of the toner measured while raising the temperature of the toner at a rate of 2 ° C./min, the storage elastic modulus is 1.0 × 10 ⁸ Pa Temperature (temperature T _A ) is 45.0 ° C. or higher, storage elastic modulus 2.0 × 10 ⁶ Pa temperature (temperature T _B ) is 60 ° C. or higher and 80 ° C. or lower, storage elastic modulus 1.0 × The temperature (temperature T _C ) of 10 ⁵ Pa (temperature T _D ) is 70 ° C. or more and 100 ° C. or less, and the temperature (temperature T _C ) of the storage elastic modulus 5 ° C. lower than the temperature of the storage elastic modulus 1.0 × 10 ⁵ Pa is 5. Maximum change rate of storage elastic modulus in the second temperature range (specifically, a temperature range in which the storage elastic modulus changes from 1.0 × 10 ⁶ Pa to 1.0 × 10 ⁵ Pa) which is 0 × 10 ⁵ Pa or more the first temperature region (specifically, temperature at which the storage modulus is changed to 2.0 × 10 ⁶ Pa from 1.0 × 10 ⁸ Pa It was greater than the maximum rate of change of storage modulus at frequency) (see Table 4). The difference between the maximum change rate of the storage elastic modulus in the first temperature range and the maximum change rate of the storage elastic modulus in the second temperature range was larger in the toner TA-1 than in the toner TA-2. The reason is considered that the ratio of the amount of the second non-crystalline resin to the amount of the first non-crystalline resin was larger in the toner TA-1 than in the toner TA-2 (see Table 1). . In the toner TA-1, since the amount of the crystalline resin in the incompatible state was large, it is considered that the storage elastic modulus changed rapidly in the second temperature range.

In the storage elastic modulus temperature dependency curve of each of toners TA-1 to TA-2, there is a first shoulder in a temperature range of temperature ± 10 ° C. of storage elastic modulus 1.0 × 10 ⁸ Pa, and storage The second shoulder was present in a temperature range of temperature ± 10 ° C. of elastic modulus 1.0 × 10 ⁶ Pa. Further, the storage elastic modulus temperature dependence curve of each toner has a third temperature range in which the storage elastic modulus is maintained in the range of 6.0 × 10 ⁶ Pa or more and 6.3 × 10 ⁶ Pa or less, and The width of the third temperature range was 10 ° C. or more.

  As shown in Table 5, the toners TA-1 to TA-2 were all excellent in heat resistant storage stability, low temperature fixing ability, and document offset resistance. By lowering the fixing temperature of the toner, it is possible to reduce the power consumption of the image forming apparatus (more specifically, a copier, a printer, a multifunction machine, etc.). In addition, even in the case of printing a large amount of documents, it is possible to suppress the occurrence of document offset between the sheets stacked on the delivery unit. By suppressing the occurrence of such document offsets, high quality documents can be manufactured. In addition, by suppressing the aggregation of toner particles at the time of transportation and storage of the toner, the cost for cooling the toner, and hence the cost for manufacturing and selling the toner can be reduced.

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

Claims (7)

A toner comprising a plurality of toner particles containing a crystalline resin, wherein
The toner particles further contain a first noncrystalline resin and a second noncrystalline resin.
The absolute value of the difference between the SP value of the crystalline resin and the SP value of the first non-crystalline resin is the absolute value of the difference between the SP value of the crystalline resin and the SP value of the second non-crystalline resin. Greater than
The storage elastic modulus temperature dependency curve of the toner measured while raising the temperature of the toner at a speed of 2 ° C./min changes the storage elastic modulus from 1.0 × 10 ⁸ Pa to 2.0 × 10 ⁶ Pa A first temperature range and a second temperature range in which the storage elastic modulus changes from 1.0 × 10 ⁶ Pa to 1.0 × 10 ⁵ Pa,
In the storage elastic modulus temperature dependency curve, the temperature of storage elastic modulus 1.0 × 10 ⁸ Pa is 45 ° C. or higher, and the temperature of storage elastic modulus 2.0 × 10 ⁶ Pa is 60 ° C. or higher and 80 ° C. or lower ^{5. The} storage elastic modulus is 1.0 × 10 ⁵ Pa and the temperature is 70 ° C. to 100 ° C., and the storage elastic modulus is 5 ° C. lower than the temperature of the storage elastic modulus 1.0 × 10 ⁵ Pa. The toner having a change rate of 0 × 10 ⁵ Pa or more and a maximum change rate of storage elastic modulus in the second temperature range is larger than a maximum change rate of storage elastic modulus in the first temperature range. In the storage elastic modulus temperature dependency curve, a first shoulder exists in a temperature range of temperature ± 10 ° C. of storage elastic modulus 1.0 × 10 ⁸ Pa, and a temperature ± of storage elastic modulus 1.0 × 10 ⁶ Pa The toner according to claim 1, wherein a second shoulder is present in a temperature range of 10 ° C. The storage elastic modulus temperature dependence curve of the toner has a third temperature range in which the storage elastic modulus is maintained in the range of 6.0 × 10 ⁶ Pa or more and 6.3 × 10 ⁶ Pa or less,
The toner according to claim 2, wherein the width of the third temperature range is 10 ° C. or more. The glass transition point of each of the first noncrystalline resin and the second noncrystalline resin is 48 ° C. or more and 60 ° C. or less,
The toner according to any one of claims 1 to 3, wherein a softening point of the crystalline resin is 80 ° C or more and 100 ° C or less. The difference between the SP value of the crystalline resin and the SP value of the first non-crystalline resin is 1.2 (cal / cm ³ ) ^1/2 or more in absolute value,
The difference between the SP value of the crystalline resin and the SP value of the second non-crystalline resin is 1.0 (cal / cm ³ ) ^1/2 or less as an absolute value. The toner according to one item. The first non-crystalline resin is a non-crystalline polyester resin having a glass transition temperature of 48 ° C. to 60 ° C. and a softening point of 80 ° C. to 90 ° C.,
The second non-crystalline resin is a non-crystalline polyester resin having a glass transition temperature of 48 ° C. to 60 ° C. and a softening point of 120 ° C. to 150 ° C.,
The toner according to any one of claims 1 to 5, wherein the crystalline resin is a crystalline polyester resin having a softening point of 80 ° C to 100 ° C. The toner is a crushed toner,
The toner according to claim 6, wherein a mass of the first non-crystalline resin is 1 to 8 times a mass of the second non-crystalline resin.

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