JP4458003B2 - Electrostatic latent image developing toner, electrostatic latent image developer, and image forming method - Google Patents

Description

  The present invention relates to an electrostatic latent image developing toner, an electrostatic latent image developer, and an image forming method used when developing an electrostatic latent image formed by an electrophotographic method or an electrostatic recording method with a developer. .

A method of visualizing image information through an electrostatic charge image such as electrophotography is currently used in various fields. In electrophotography, an electrostatic charge image is formed on a photoreceptor by charging and exposure processes, the electrostatic latent image is developed with a developer containing toner, and visualized through a transfer and fixing process.
As the developer used here, a two-component developer composed of a toner and a carrier and a one-component developer using a magnetic toner or a non-magnetic toner alone are known. A kneading and pulverizing method is used in which a plastic resin is melt-kneaded together with a release agent such as a pigment, a charge control agent, and a wax, and after cooling, is finely pulverized and classified, and has some problems as described below.

  In the ordinary kneading and pulverizing method, the toner shape and the surface structure of the toner are indeterminate, and although it varies slightly depending on the pulverization properties of the materials used and the conditions of the pulverization process, it is difficult to control the intentional toner shape and surface structure. . In the kneading and pulverizing method, the range of material selection is limited. Specifically, the resin colorant dispersion must be sufficiently brittle and capable of being finely pulverized by an economically possible production apparatus. However, if the resin colorant dispersion is made brittle to satisfy these requirements, finer powder may be generated or the toner shape may be changed due to mechanical shearing force applied in the developing machine.

  Due to these effects, in the two-component developer, the charging deterioration of the developer due to adhesion of fine powder to the carrier surface is accelerated, and in the one-component developer, toner scattering occurs due to the expansion of the particle size distribution. Deterioration in developability due to changes in image quality tends to cause image quality degradation. In addition, when a toner is formed by adding a large amount of a release agent such as wax, exposure to the release agent on the surface is often affected by the combination with a thermoplastic resin. In particular, in the case of a combination of a resin having increased elasticity due to a high molecular weight component and slightly pulverized resin and a brittle wax such as polyethylene or polypropylene, exposure of these wax components is often observed on the toner surface. This is advantageous for releasability at the time of fixing and cleaning of untransferred toner from the photoreceptor, but the polyethylene on the surface layer is easily transferred by mechanical force, resulting in contamination of the developing roll, photoreceptor and carrier. It becomes easy and leads to a decrease in reliability.

  In addition, since the toner shape is irregular, the fluidity may not be sufficient even with the addition of a fluidity aid, and the time-dependent movement of the fine particles on the toner surface due to the mechanical shearing force during use may occur. When the fluidity is lowered or the fluidity aid is buried in the toner, the developability, transferability, and cleaning properties are deteriorated. Further, when the toner collected by cleaning is returned to the developing machine and used again, the image quality is likely to further deteriorate. On the other hand, when the flow aid is further increased in order to prevent these, the generation of black spots on the photoreceptor and the scattering of the aid particles occur.

As described above, in the electrophotographic process, in order to stably maintain the performance of the toner even under various mechanical stresses, the surface hardness can be maintained without suppressing the exposure of the release agent to the surface or the fixing property. In addition, it is necessary to improve the mechanical strength of the toner itself and to achieve both sufficient charging and fixing properties.
In recent years, the demand for higher image quality has increased, and in image formation, there has been a significant trend toward toner diameter reduction in order to realize high-definition images.
However, with the simple reduction in size while maintaining the conventional particle size distribution, the presence of fine powder side toner causes significant problems of carrier and photoconductor contamination and toner scattering, making it difficult to achieve high image quality and high reliability at the same time. It is. For this purpose, it is necessary that the particle size distribution can be sharpened and the particle size can be reduced.

  In recent years, as means for intentionally enabling control of toner shape and surface structure, a toner production method by emulsion polymerization aggregation (see, for example, Patent Documents 1 and 2), suspension polymerization toner, suspension granulation toner, A wet process toner manufacturing method such as a suspension emulsification aggregation unity toner has been proposed.

  These wet process toners are suitable for the production of toner particles having a sharp particle size distribution and small particle diameters. Particularly, the agglomerated and coalesced toners are excellent in control of the toner surface shape, and the chargeability and durability are improved. Can be planned.

  As a further requirement, in order to reduce the amount of energy used in copying machines and printers, a technology for fixing toner with lower energy is desired, and there is a strong demand for toner for electrophotography that can be fixed at a lower temperature.

  As a means for lowering the toner fixing temperature, a technique for lowering the glass transition point of a toner resin (binder) is generally performed. However, if the glass transition point is too low, powder aggregation (blocking) is likely to occur or the toner on the fixed image is not stored, so practically 50 ° C. is the lower limit, preferably 60 ° C. is required.

  This glass transition point is a design point of many resin for toners currently on the market, and there is a problem that a toner capable of fixing at a lower temperature cannot be obtained by the method of lowering the glass transition point. Although the fixing temperature can be lowered by using a plasticizer, there is a problem because blocking occurs during storage of the toner or in the developing machine.

  Under such circumstances, while there is a tendency to increase the outside air temperature due to recent warming, it is becoming necessary to prevent blocking in the vicinity of 60 ° C. when exposed to direct sunlight during the course of distribution. Further, as a means for achieving both image storability up to 60 ° C. and low-temperature fixability, a technique using a crystalline resin as a binder constituting the toner can be considered. For the purpose of both blocking prevention and low-temperature fixability, crystallinity is considered. A method of using a resin as a toner has been known for a long time (for example, see Patent Document 3).

  On the other hand, for the purpose of preventing offset (for example, see Patent Document 4) and pressure fixing (for example, see Patent Document 5), a technique using a crystalline resin has been known for a long time. In addition, a technique of applying a polymer having an alkyl group side chain having 14 or more carbon atoms to a toner as a crystalline resin has been proposed (see, for example, Patent Document 6). The melting point of the powder was as low as 62 to 66 ° C., too low, and there was a problem in the reliability of powder and images. Furthermore, the techniques of Patent Documents 4 and 5 have a problem that the fixing performance of the crystalline resin to paper is not sufficient.

  On the other hand, Patent Document 6 further includes a polyester resin as a crystalline resin that is expected to improve the fixability to paper. As a technique using the crystalline polyester resin in a toner, a non-crystalline resin having a glass transition temperature of 40 ° C. or higher is used. A technique for mixing a crystalline polyester resin and a crystalline polyester resin having a melting point of 130 to 200 ° C. has been proposed. However, this technique has excellent pulverization properties and blocking resistance, but has a problem in that the low-temperature fixability cannot be achieved since the crystalline polyester resin has a high melting point.

  Furthermore, a technique for obtaining low-temperature fixing by mixing a low-melting crystalline resin and an amorphous resin and controlling the degree of compatibilization has been proposed (see, for example, Patent Documents 7 and 8). However, as the compatibilization of the crystalline resin and the amorphous resin proceeds, plasticization of the mixed resin occurs, resulting in problems such as not only blocking resistance but also deterioration of chargeability at high temperature and high humidity. .

  Polyester resin is used as a binder resin in place of styrene / acrylic resin, which has been widely used, and is excellent in low-temperature fixability and heat-resistant storage, and its use has recently been attempted. However, the polyester resin has a lower dispersibility of the release agent (wax) than the styrene / acrylic resin in the kneading and pulverization method, and is easily pulverized at the interface between the binder resin and the release agent during pulverization. There is a problem that the release agent is exposed to the toner and the toner powder characteristics and charging characteristics are deteriorated. Also in the coalescence and fusion coalescence method, which is a wet production method, when coalescing and coalescing by heating, the release agent is exposed to the toner surface or detached from the toner particles simultaneously with the coalescence of the release agent by heat. Therefore, there are problems such as deterioration of toner powder characteristics and charging characteristics.

  Here, as a means of improving the dispersibility of the polyester resin and wax in the toner, it is proposed to improve the dispersibility by defining the solubility parameter of the binder resin and the wax and the solubility parameter difference between the binder resin and the wax. (For example, see Patent Documents 9 to 13). However, even if these means are used, it is insufficient to suppress the exposure of the wax component to the toner surface, and is insufficient as an effect of suppressing the contamination of the wax component to a member such as a developing roll or a photoreceptor or a carrier. Met.

  Further, as means for enabling control of the toner shape and surface structure, including suppression of exposure of the wax component to the toner surface, a toner production method by emulsion polymerization aggregation, suspension polymerization, suspension granulation, suspension, A wet process toner manufacturing method such as a turbid emulsion aggregation method has been proposed (see, for example, Patent Documents 14 and 15). The wet process toner is more preferable because it is suitable for the production of toner particles having a sharp particle size distribution and a small particle diameter, and a high-definition image can be realized in image formation. In particular, in terms of toner surface shape controllability, the agglomerated and coalesced toner is excellent, and can improve the chargeability, durability, and cleaning properties.

  Furthermore, as a means for achieving both blocking prevention, image storage stability, and low-temperature fixability, a technique using a crystalline resin as a binder constituting the toner is considered (see, for example, Patent Documents 16 to 18). A technique using a crystalline resin has been known for a long time for the purpose of preventing offset (for example, see Patent Document 19) and pressure fixing (for example, see Patent Document 20). However, the technique of Patent Document 16 applies a polymer having an alkyl group side chain having 14 or more carbon atoms to the toner, and has a problem in the reliability of powder and images. Further, the crystalline resins described in Patent Documents 17 and 18 have a problem that the fixing performance to paper is not sufficient.

  On the other hand, a polyester resin is cited as a crystalline resin that is expected to improve the fixability to paper, and a technique using the crystalline polyester resin in a toner is described in Patent Document 18. This is a technique in which an amorphous polyester resin having a glass transition temperature of 40 ° C. or higher and a crystalline polyester resin having a melting point of 130 to 200 ° C. are mixed and used. However, this technique has excellent pulverization properties and blocking resistance, but has a problem in that the low-temperature fixability cannot be achieved since the crystalline polyester resin has a high melting point.

  On the other hand, a technique for obtaining low-temperature fixing by mixing a low-melting crystalline resin and an amorphous resin and controlling the degree of compatibilization has been proposed (see, for example, Patent Documents 21 and 22). Furthermore, there is a technology that uses a mixture of crystalline polyester and amorphous resin, and prevents blocking between papers during discharge without compromising transparency by compatibilizing the crystalline part due to the temperature history during fixing. It has been introduced (for example, see Patent Document 23). However, as the compatibilization of the crystalline resin and the amorphous resin progresses, plasticization of the mixed resin occurs, and not only blocking resistance, but also pressure and heat are applied to the image, such as transportation and transportation of printed matter, and in the car in summer. When added, the toner image is transferred to the opposite surface, causing a problem of image loss.

As described above, in the electrophotographic process, in order to stably maintain the performance of the toner even under various mechanical stresses, the surface hardness can be maintained without suppressing the exposure of the release agent to the surface or the fixing property. In addition, it is necessary to improve the mechanical strength of the toner itself and to achieve both sufficient charging and fixing properties. In other words, the existing technologies have achieved high reliability such as compatibility between low-temperature fixability and offset, toner storage stability, fixed image storage stability and toner chargeability, and sharpening of the toner particle size distribution accompanying the demand for higher image quality. It has been difficult to satisfy all the problems in the toner manufacturing method suitable for the reduction in size and particle size.
Japanese Patent Laid-Open No. 63-282275 JP-A-6-250439 Japanese Patent Publication No. 56-13943 Japanese Examined Patent Publication No.62-39428 Japanese Patent Publication No. 63-25335 Japanese Patent Publication No. 56-13943 JP 2004-206081 A Japanese Patent Laid-Open No. 2004-50478 JP 2000-352841 A JP 2000-35695 A Japanese Patent Laid-Open No. 11-38677 JP 2003-25558 A Japanese Patent Laid-Open No. 2003-28024 Japanese Patent Laid-Open No. 63-282275 JP-A-6-250439 Japanese Patent Publication No. 56-13943 Japanese Examined Patent Publication No.62-39428 Japanese Patent Publication No. 63-25335 Japanese Examined Patent Publication No.62-39428 Japanese Patent Publication No. 63-25335 JP 2004-206081 A Japanese Patent Laid-Open No. 2004-50478 Japanese Patent Laid-Open No. 2003-50478

  Accordingly, an object of the present invention is to solve the conventional problems and achieve the following object. That is, the present invention provides a toner for developing an electrostatic image that solves the above-mentioned problems in the conventional toner, and a method for producing the same. That is, the present invention is excellent in fixing property at low temperature, charging property, and toner blocking property at a high temperature particularly near 60 ° C., and has a low process speed dependency on fixing performance. An object is to provide a developer for developing an electrostatic latent image and an image forming method.

The above problems are solved by the present invention described below. That is,
The electrostatic image developing toner of the present invention is
Toner base particles containing a crystalline resin A and an amorphous polymer B as a binder resin, the surface of which is coated with a surface layer mainly composed of an amorphous polymer C different from the amorphous polymer B;
One or more amorphous polymeric external additives D;
Have
The endothermic peak temperature TmA [° C.] derived from the crystalline resin A, the endothermic peak TmAB [° C.] derived from the crystalline resin A when the crystalline resin A and the amorphous polymer B are mixed, and the crystalline resin The endothermic peak temperature TmAC [° C.] derived from the crystalline resin A when the A and the amorphous polymer C are mixed, and the crystalline resin A when the crystalline resin A and the amorphous polymer external additive D are mixed The derived endothermic peak temperature TmAD [° C.] satisfies the relationship of the following formula (1).
TmAD <TmAB <TmAC ≦ TmA Formula (1)

  In the toner for developing an electrostatic charge image of the present invention, it is preferable that the amount of the amorphous polymer external additive D is 0.1% by mass to 20% by mass with respect to the toner base particles.

  The electrostatic image developer of the present invention is characterized by containing the above-described toner for developing an electrostatic latent image of the present invention and a carrier.

The image forming method of the present invention includes
A latent image forming step of forming an electrostatic latent image on the latent image carrier, a developing step of developing the electrostatic latent image with a developer containing toner to form a toner image, and the toner image on a transfer material An image forming method including a transfer step of forming a transfer image by transferring to a transfer step, and a fixing step of fixing the transfer image,
The toner is the electrostatic latent image developing toner described in the invention.

  The present invention provides a toner for developing an electrostatic latent image, a developer for developing an electrostatic latent image, and an image forming method that solve the above-described problems in the conventional toner. That is, the present invention provides a toner for developing an electrostatic latent image, which has excellent chargeability at high temperature and high humidity, and excellent toner blocking property at a high temperature near 60 ° C. An image developing developer and an image forming method can be provided.

The toner for developing an electrostatic charge image of the present invention comprises a crystalline resin A and an amorphous polymer B as a binder resin, and a surface layer mainly comprising an amorphous polymer C whose surface is different from that of the amorphous polymer B. In the toner comprising toner mother particles for developing an electrostatic charge image coated with 1 and at least one amorphous polymer external additive D, the endothermic peak temperature TmA [° C.] derived from the crystalline resin A and the crystallinity The endothermic peak TmAB [° C.] derived from the crystalline resin A when the resin A and the amorphous polymer B are mixed, and the endothermic derived from the crystalline resin A when the crystalline resin A and the amorphous polymer C are mixed. Crystalline resin A when peak temperature TmAC [° C.] is mixed with crystalline resin A and amorphous polymer external additive D (hereinafter, the constituent polymer is referred to as amorphous polymer D for external addition). The endothermic peak temperature TmAD [° C.] derived from the following formula (1) It is set to satisfy the relationship.
TmAD <TmAB <TmAC ≦ TmA Formula (1)
Hereinafter, the electrostatic image developing toner of the present invention (hereinafter sometimes simply referred to as “the toner of the present invention”) will be described in detail.

  Here, in the toner of the present invention, the “crystalline resin” refers to a resin having a clear endothermic peak rather than a stepwise endothermic amount change in differential scanning calorimetry (DSC). Specifically, a resin whose half-value width of the endothermic peak when measured at a temperature rising rate of 10 ° C./min is within 6 ° C. is defined as “crystalline resin”, and other resins, specifically, half A resin having a value range exceeding 6 ° C. or a resin having no clear endothermic peak is defined as an amorphous polymer (amorphous resin). In addition, even if it does not have a clear endothermic peak in the second temperature raising step, it is “crystalline resin” if it has a clear endothermic peak in the first temperature raising step. As the amorphous polymer used in the present invention, it is preferable to use a resin in which no clear endothermic peak is observed.

  In the toner of the present invention, the TmA [° C.], TmAB [° C.], TmAC [° C.], and TmAD [° C.] are measured by a differential scanning calorimeter (manufactured by Max Science: DSC3110, thermal analysis system 001, Hereinafter, the measurement was performed using a thermal analyzer of “DSC”. In the first temperature raising step, the temperature is raised from room temperature to 150 ° C. at a rate of 10 ° C. per minute, held at 150 ° C. for 5 minutes, and then liquefied nitrogen is used to reach 0 ° C. at a rate of 10 ° C. per minute. After the temperature was lowered and held at 0 ° C. for 5 minutes, the temperature was raised again from 0 ° C. to 150 ° C. at a rate of 10 ° C. as the second temperature raising step, and the obtained differential scanning calorimetry curve was JIS K-7121: 87. And an endothermic peak was obtained.

  The TmAB [° C.] is obtained by mixing the crystalline resin A and the amorphous polymer B with 20 parts by mass of the crystalline resin A and 80 parts by mass of the amorphous polymer B, and then placing the sample on an aluminum dish. The sample was measured after standing at 100 ° C. for 2 hours, gradually cooling at room temperature, and then pulverizing the molten sample with a mortar. The TmAC [° C.] is obtained by mixing the crystalline resin A and the amorphous polymer C with 20 parts by mass of the crystalline resin A and 80 parts by mass of the amorphous polymer C, and then placing the sample on an aluminum dish. This was measured as a sample obtained by allowing the sample to stand at 2 ° C. for 2 hours and gradually cooling at room temperature, and then crushing the molten sample with a mortar. The TmAD [° C.] is obtained by mixing the crystalline resin A and the amorphous polymer external additive D with 20 parts by mass of the crystalline resin A and 80 parts by mass of the amorphous polymer D for external addition, The sample was placed on an aluminum dish, allowed to stand at 100 ° C. for 2 hours, slowly cooled at room temperature, and then measured by using a crushed crushed sample as a sample.

  In the present invention, low temperature fixability due to melting point drop during fixing melting of crystalline resin A and prevention of toner blocking property due to excessive compatibility in the powder state and deterioration of charging property at high temperature and high humidity are prevented. This is important. The crystalline resin A and the amorphous polymer B used in the present invention are in an appropriate compatible state and contribute to low-temperature fixing, but the blocking property deteriorates as it is. Furthermore, blocking resistance is imparted by applying a surface coating with the amorphous polymer C having a low compatibility with the crystalline resin A.

  Here, in order to achieve further low-temperature fixing, an externally added amorphous polymer D that is highly compatible with the crystalline resin A is externally added. However, since there is an amorphous polymer C in a powder state from room temperature to about 60 ° C. The amorphous polymer D for external addition, which is highly compatible with the crystalline resin A, is not compatible but maintains the blocking property, but the crystalline resin A inside and the amorphous polymer D for external addition melt at the time of fixing and melting. By the compatibility, lowering of the melting point is further promoted and low temperature fixing can be realized. This is because, in addition to the sharp melt property that the crystalline resin A originally has, a sharp melt and low temperature fixability can be exhibited by the plasticizing effect of the compatibilized portion.

  Further, the crystalline resin A and the amorphous polymer B are appropriately compatible with each other, so that the dispersibility of the crystalline resin A is improved and the strength of the toner can be secured.

  As an index representing the degree of compatibilization between the crystalline resin A and the amorphous polymer B, it is most effective to represent the change in the endothermic peak temperature derived from the crystalline resin A in differential scanning calorimetry (DSC). For example, it is shown that the crystalline resin A and the amorphous polymer B are compatibilized so that the crystallinity of the crystalline resin A is lost and the melting point of the crystalline resin is lowered. The endothermic peak temperature derived from the crystalline resin A is also significantly reduced.

  The melting point drop and plasticization of the amorphous polymer due to this compatibilization show excellent sharp melt properties and low temperature fixability, but on the other hand it causes deterioration of heat storage properties such as blocking resistance. By covering the crystalline resin A and the amorphous polymer B with the surface layer mainly composed of the amorphous polymer C having low compatibility with the crystalline resin A different from the amorphous polymer B Both the compatibilized crystalline resin A and amorphous polymer B, and the uncompatibilized crystalline resin A can be suppressed from being exposed to the toner particle surface.

  This utilizes the relative relationship between the degree of compatibilization between the crystalline resin A and the amorphous polymers B and C, and by positioning the amorphous polymer C that is difficult to compatibilize with the crystalline resin on the toner particle surface layer, Even in a wet process toner using an agglomeration and coalescence method in which the aggregated particles are coalesced by raising the temperature above the glass transition temperature of the binder resin, the crystalline resin A is exposed to the toner particle surface or the phase of the toner surface layer The melting point of the crystalline resin A and the influence of plasticization of the amorphous polymer B or C due to the melting can be suppressed, thereby maintaining the high-temperature blocking resistance of the toner, and excellent sharp melt properties It became possible to obtain low-temperature fixability. Furthermore, the amorphous polymer D for external addition, which is highly compatible with the crystalline resin A, has a surface coating layer of the amorphous polymer C in a powder state from room temperature to 60 ° C. While maintaining the blocking property, the crystalline resin A and the amorphous polymer D for external addition are melted and compatible at the time of fixing and melting, causing a melting point drop and plasticizing of the amorphous polymer, thereby further fixing at a low temperature. It becomes possible.

  For the above reasons, the relationship of TmAB <TmAC ≦ TmA and the relationship of TmAD lower than these TmAB, TmAC, and TmA are satisfied, that is, by satisfying the above formula (1), the fixing property at low temperature is ensured. On the other hand, it is possible to achieve a high level of chargeability at high temperatures and high humidity, and toner blocking properties at high temperatures particularly near 60 ° C.

In the toner of the present invention, the amorphous polymer B is amorphous polyester resin B ', and the solubility parameter SP _A of the crystalline resin A, and the solubility parameter SP _B of the amorphous polymer B, the Mu shaped polymer C solubility parameter SP _C, and a solubility parameter SP _D of the outer添用amorphous polymer D, preferably satisfy the relation of the following formula (2).
_{| SP A -SP D | <|} SP A -SP B | <| SP A -SP C | ··· formula (2)

The solubility parameter (hereinafter sometimes referred to as “SP value”) was calculated by the method of Fedors et al. [Polym. Eng. Sci. , Vol14, p147 (1974)].
SP value = (ΣΔei / ΣΔvi) ^1/2
Δei: Evaporation energy of atom or atomic group Δvi: Molar volume of atom or atomic group

  When the crystalline resin A and the amorphous polyester resin B ′ are incompatible with each other and have a layer separation structure, the crystalline resin A used as a binder resin can be used to obtain a sharp melt property (low temperature fixability). It is desirable to increase the ratio, but in that case, the strength of the toner itself is extremely reduced, and the external additive is buried by stirring with the carrier in the developing device, or the cleaning member or direct charging, transfer member Occurrence of toner crushing due to image formation or image strength after fixing may be significantly reduced. In addition, when the compatibility of the crystalline resin A and the amorphous polyester resin B ′ is excessively advanced, the crystallinity of the crystalline resin A is lost, the melting point of the crystalline resin is lowered, and the amorphous polyester resin B ′ Although plasticization occurs and exhibits excellent sharp melt properties and low-temperature fixability, if the plasticized amorphous polyester resin B ′ is present on the surface of the toner particles, heat storage properties and chargeability are deteriorated. There is a case.

  Further, the core particles containing the crystalline resin A and the amorphous polyester resin B ′ are coated with a surface layer mainly composed of an amorphous polymer C having a low compatibility with the crystalline resin A, thereby providing an amorphous Both the high-quality polyester resin B ′ and the crystalline resin A in the crystalline state can suppress the exposure on the surface of the toner particles, and can achieve both excellent heat storage properties and chargeability and low-temperature fixability.

The amorphous polymer D for external addition is preferably highly compatible with the crystalline resin A in order to realize low-temperature fixing. Therefore, it is preferable that the difference in SP _D of SP _A and the outer添用amorphous polymer D of the crystalline resin A (absolute value) of 1.0 or less, more preferably 0.8 or less, More preferably, it is 0.7 or less.

In addition, it is preferable that the amorphous polymer D for external addition is incompatible with the amorphous polymer C because the toner exhibits high blocking resistance in a powder state from room temperature to 60 ° C. In this reason, it is preferable that the difference between the SP _D of SP _C and outer添用amorphous polymer D of amorphous polymer C (absolute value) of 0.3 or more, more preferably 0.4 or more Yes, more preferably 0.5 or more.

Further, the SP B of the crystalline resin A and the amorphous polymer B is preferably such that SP _B is larger than SP _A. When SP _B is less than or equal to SP _A , the compatibility of the crystalline resin A and the amorphous polymer B increases, the plasticization of the binder resin increases, and the amorphous polymer located in the surface layer. Since compatibility with C also increases, exposure of the crystalline resin A to the surface layer or plasticization of the amorphous polymer C may progress, which may cause deterioration of the heat storage property of the toner.

  The crystalline resin A is preferably contained in an amount of 5 to 50% by mass with respect to the toner base particles. More preferably, it is 10-30 mass%. If the content of the crystalline resin exceeds 50% by mass, good fixing characteristics can be obtained, but the phase separation structure in the fixed image becomes non-uniform, and the strength of the fixed image, particularly the scratch strength, is reduced, and scratches are generated. It may become easy to stick. On the other hand, when the content of the crystalline resin is less than 5% by mass, a sharp melt property derived from the crystalline resin A cannot be obtained, and the amorphous polymer B is simply plasticized, and good low-temperature fixing is achieved. In some cases, the toner blocking resistance and the image storability cannot be maintained while securing the properties.

  The amorphous polymer B is preferably contained in an amount of 10 to 85% by mass with respect to the toner base particles. More preferably, it is 30-50 mass%. If it is less than 10% by mass, the toner strength is insufficient, and if it exceeds 85% by mass, the crystalline resin is decreased and the low-temperature fixability may be insufficient.

  The amorphous polymer C is preferably contained in an amount of 10 to 40% by mass with respect to the toner base particles. More preferably, it is 20-35 mass%. If it is less than 10% by mass, the blocking resistance is insufficient, and if it exceeds 40% by mass, the surface coating layer becomes too thick, and the crystalline resin A and the amorphous polymer D for external addition are not easily compatible with each other at low temperature. Fixability may be insufficient.

  The amorphous polymer external additive D is preferably contained in an amount of 0.1 to 20% by mass with respect to the toner base particles. More preferably, it is 10-15 mass%. If it is less than 0.1% by mass, the effect of low-temperature fixability due to compatibility with the crystalline resin A is small, and if it exceeds 20% by mass, problems such as filming may occur.

  In the present invention, the difference obtained by subtracting TmAB [° C.] from TmAC [° C.] is preferably 1 ° C. to 20 ° C., more preferably 5 ° C. to 15 ° C. When the difference obtained by subtracting TmAB [° C.] from TmAC [° C.] is 1 ° C. to 20 ° C., excellent sharp melt property and low temperature fixability can be obtained while maintaining the blocking resistance of the toner at high temperature. The effect that it becomes possible becomes more remarkable.

  In the present invention, the difference obtained by subtracting TmAD [° C.] from TmAC [° C.] is preferably −1 ° C. to −20 ° C., and more preferably −5 ° C. to −15 ° C. When the difference obtained by subtracting TmAD [° C.] from TmAC [° C.] is −1 ° C. to −20 ° C., excellent sharp melt property and low temperature fixability are obtained while maintaining the blocking resistance of the toner at high temperature. The effect that it becomes possible becomes more remarkable.

  In the present invention, the difference obtained by subtracting TmAD [° C.] from TmAB [° C.] is preferably −1 ° C. to −20 ° C., more preferably −5 ° C. to −15 ° C. When the difference obtained by subtracting TmAD [° C.] from TmAB [° C.] is −1 ° C. to −20 ° C., excellent sharp melt property and low temperature fixability are obtained while maintaining the blocking resistance of the toner at high temperature. The effect that it becomes possible becomes more remarkable.

  The toner of the present invention contains a crystalline resin A and an amorphous polymer B, and the surface is coated with a surface layer mainly composed of an amorphous polymer C that is the same as or different from the amorphous polymer B. In the toner containing the developing toner base particles and at least one or more amorphous polymer external additives D, the constituents are not particularly limited as long as the relationship of the above formula (1) is satisfied. Other components may be included. The method for producing the toner of the present invention is not particularly limited, but it is preferable to use a wet method as described later.

  Hereinafter, the components of the toner of the present invention will be described in detail.

  First, the crystalline resin A will be described. The crystalline resin A is not particularly limited as long as it is a resin having crystallinity, and specifically includes a crystalline polyester resin and a crystalline vinyl resin. From the viewpoint of chargeability and adjustment of the melting point within a preferred range, a crystalline polyester is preferred. An aliphatic crystalline polyester resin having an appropriate melting point is more preferable.

  The crystalline polyester resin and all other polyester resins used in the toner of the present invention are synthesized from a polyvalent carboxylic acid component and a polyhydric alcohol component. In the present invention, a commercially available product may be used as the polyester resin, or an appropriately synthesized product may be used. Hereinafter, the crystalline polyester resin preferably used as the crystalline resin A will be described.

Examples of the polyvalent carboxylic acid component include oxalic acid, succinic acid, glutaric acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1, Aliphatic dicarboxylic acids such as 12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, mesaconine Aromatic dicarboxylic acids such as dibasic acids such as acids, and the like, and anhydrides and lower alkyl esters thereof are also included, but not limited thereto.
Examples of trivalent or higher carboxylic acids include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and the like, and anhydrides thereof. And lower alkyl esters. These may be used individually by 1 type and may use 2 or more types together.

  Furthermore, the polyvalent carboxylic acid component preferably contains a dicarboxylic acid component having a sulfonic acid group in addition to the aliphatic dicarboxylic acid and aromatic dicarboxylic acid described above. The dicarboxylic acid having a sulfonic acid group is effective in that it can favorably disperse a coloring material such as a pigment. In addition, when the entire crystalline polyester resin is emulsified or suspended in water to produce fine particles, if a sulfonic acid group is present, it can be emulsified or suspended without using a surfactant as described later. is there.

  Examples of the dicarboxylic acid having a sulfonic acid group include, but are not limited to, 2-sulfoterephthalic acid sodium salt, 5-sulfoisophthalic acid sodium salt, and sulfosuccinic acid sodium salt. Moreover, these lower alkyl esters, acid anhydrides, etc. are also mentioned. The divalent or higher carboxylic acid component having a sulfonic acid group is preferably contained in an amount of 0 to 20 mol%, and preferably 0.5 to 10 mol%, based on all polyvalent carboxylic acid components constituting the polyester. It is more preferable. When the content of the divalent or higher carboxylic acid component is less than 0.5 mol%, the stability over time of the emulsified particles may deteriorate. If it exceeds 10 mol%, not only the crystallinity of the polyester resin will be lowered, but also the process of fusing the particles after agglomeration will be adversely affected and it may be difficult to adjust the toner diameter.

  Furthermore, it is more preferable to contain a dicarboxylic acid component having a double bond in addition to the aforementioned aliphatic dicarboxylic acid and aromatic dicarboxylic acid. A dicarboxylic acid having a double bond can be suitably used to prevent hot offset at the time of fixing in that it can be radically cross-linked through the double bond. Examples of such dicarboxylic acids include, but are not limited to, maleic acid, fumaric acid, 3-hexenedioic acid, 3-octenedioic acid, and their lower esters and acid anhydrides. Among these, fumaric acid and maleic acid are preferable in terms of cost.

  The polyhydric alcohol component is preferably an aliphatic diol, and more preferably a linear aliphatic diol having a main chain portion having 7 to 20 carbon atoms. When the aliphatic diol is branched, the crystallinity of the polyester resin is lowered and the melting point is lowered, so that toner blocking resistance, image storage stability, and low-temperature fixability may be deteriorated. Further, when the number of carbon atoms is less than 7, when polycondensation with an aromatic dicarboxylic acid, the melting point becomes high and fixing at low temperature may be difficult. On the other hand, when the number of carbon atoms exceeds 20, it may be difficult to obtain practical materials. The aliphatic diol preferably has 7 to 14 carbon atoms.

Specific examples of the aliphatic diol suitably used for the synthesis of the crystalline polyester used in the toner of the present invention include ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,5. -Pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12- Examples include dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,14-eicosandecanediol, and the like, but are not limited thereto. Among these, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferable in view of availability.
Examples of the trivalent or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol. These may be used individually by 1 type and may use 2 or more types together.

  Among the polyhydric alcohol components, the content of the aliphatic diol component is preferably 80 mol% or more, and more preferably 90% or more. If the content of the aliphatic diol component is less than 80 mol%, the crystallinity of the polyester resin may be lowered. If necessary, monovalent acids such as acetic acid and benzoic acid and monovalent alcohols such as cyclohexanol benzyl alcohol can be used for the purpose of adjusting the acid value and hydroxyl value.

The method for producing the crystalline polyester resin is not particularly limited and can be produced by a general polyester polymerization method in which an acid component and an alcohol component are reacted. Examples thereof include direct polycondensation and transesterification. Depending on the type of monomer, it is manufactured separately.
The production of the crystalline polyester resin can be carried out at a polymerization temperature of 180 to 230 ° C., and the reaction is carried out while reducing the pressure in the reaction system as necessary to remove water and alcohol generated during condensation. When the monomer is not dissolved or compatible with the reaction temperature, a solvent having a high boiling point may be added as a solubilizer and dissolved. In the polycondensation reaction, the dissolution auxiliary solvent is distilled off. When a monomer having poor compatibility exists in the copolymerization reaction, the monomer having poor compatibility and the monomer and the acid or alcohol to be polycondensed are condensed in advance and then polycondensed together with the main component.

  The crystalline polyester resin fine particle dispersion can be prepared by adjusting the acid value of the resin and emulsifying and dispersing the resin using an ionic surfactant.

  Catalysts that can be used in the production of the crystalline polyester resin include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; metals such as zinc, manganese, antimony, titanium, tin, zirconium, and germanium Compounds: Phosphorous acid compounds, phosphoric acid compounds, amine compounds, and the like, and specific examples include the following compounds. For example, sodium acetate, sodium carbonate, lithium acetate, lithium carbonate, calcium acetate, calcium stearate, magnesium acetate, zinc acetate, zinc stearate, zinc naphthenate, zinc chloride, manganese acetate, manganese naphthenate, titanium tetraethoxide, titanium Tetrapropoxide, titanium tetraisoproxide, titanium tetrabutoxide, antimony trioxide, triphenylantimony, tributylantimony, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin oxide, zirconium tetrabutoxide, naphthenic acid Zirconium, zirconyl carbonate, zirconyl acetate, zirconyl stearate, zirconyl octylate, germanium oxide, triphenyl Sufaito, tris (2, 4-t-butylphenyl) phosphite, ethyltriphenylphosphonium bromide, triethylamine, compounds such as triphenyl amine.

As melting | fusing point of crystalline resin A, Preferably it is 50-100 degreeC, More preferably, it is 60-80 degreeC. If the melting point of the crystalline resin A is lower than 50 ° C., toner storage stability and toner image storage stability after fixing may become a problem. On the other hand, if the melting point of the crystalline resin A is higher than 100 ° C., sufficient low-temperature fixing may not be obtained as compared with conventional toners.
A crystalline resin may show a plurality of melting peaks, but in the present invention, the maximum peak is regarded as the melting point.

  On the other hand, the crystalline vinyl resin includes amyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, (meth) acrylic. Decyl acid, undecyl (meth) acrylate, tridecyl (meth) acrylate, myristyl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, oleyl (meth) acrylate, (meth) acrylic acid Examples thereof include vinyl resins using long-chain alkyl such as behenyl and alkenyl (meth) acrylic acid esters. In the present specification, the description “(meth) acryl” means to include both “acryl” and “methacryl”.

  Next, the amorphous polymer B will be described. As the amorphous polymer B, a known resin material can be used, but an amorphous polyester resin B ′ is particularly preferable. The non-crystalline polyester resin B ′ preferably used in the present invention is obtained mainly by condensation polymerization of polyvalent carboxylic acids and polyhydric alcohols. When the amorphous polyester resin B ′ is used as the amorphous polymer B, a resin particle dispersion is easily prepared by emulsifying and dispersing the resin by adjusting the acid value or using an ionic surfactant. This is advantageous in that it can.

  Examples of the polyvalent carboxylic acid in the non-crystalline polyester resin B ′ include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid; Aliphatic carboxylic acids such as acid, fumaric acid, succinic acid, alkenyl succinic anhydride, and adipic acid; cycloaliphatic carboxylic acids such as cyclohexanedicarboxylic acid, and one or more of these polyvalent carboxylic acids are used. be able to. Among these polycarboxylic acids, aromatic carboxylic acids are preferably used, and trivalent or higher carboxylic acids (trimellitic acid) together with dicarboxylic acids to form a crosslinked structure or a branched structure in order to ensure good fixing properties. And acid anhydrides thereof) are preferably used in combination.

  Examples of the polyhydric alcohol in the non-crystalline polyester resin B ′ include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentylglycol, glycerin, etc .; cyclohexanediol And alicyclic diols such as cyclohexanedimethanol and hydrogenated bisphenol A; aromatic diols such as bisphenol A ethylene oxide adduct and bisphenol A propylene oxide adduct. One or more of these polyhydric alcohols can be used. Among these polyhydric alcohols, aromatic diols and alicyclic diols are preferable, and among these, aromatic diols are more preferable. In order to secure better fixability, a trihydric or higher polyhydric alcohol (glycerin, trimethylolpropane, pentaerythritol) may be used in combination with the diol in order to form a crosslinked structure or a branched structure.

  In addition, monocarboxylic acid and / or monoalcohol is further added to the polyester resin obtained by polycondensation of polycarboxylic acid and polyhydric alcohol to esterify the hydroxyl group and / or carboxyl group at the polymerization terminal. The acid value of the polyester resin may be adjusted. Examples of the monocarboxylic acid include acetic acid, acetic anhydride, benzoic acid, trichloroacetic acid, trifluoroacetic acid, propionic anhydride, etc., and examples of the monoalcohol include methanol, ethanol, propanol, octanol, 2-ethylhexanol, trifluoroethanol, Examples include trichloroethanol, hexafluoroisopropanol, and phenol.

  The non-crystalline polyester resin B ′ can be produced by subjecting the polyhydric alcohol and polyvalent carboxylic acid to a condensation reaction according to a conventional method. For example, the polyhydric alcohol and polyhydric carboxylic acid, if necessary, a catalyst is added, blended in a reaction vessel equipped with a thermometer, a stirrer, a flow-down condenser, and in the presence of an inert gas (such as nitrogen gas), Heat at 150 to 250 ° C. to continuously remove by-product low-molecular compounds out of the reaction system, stop the reaction when a predetermined acid value is reached, cool, and obtain the desired reactant Can be manufactured.

  Examples of the catalyst used for the synthesis of the amorphous polyester resin B 'include esterification catalysts such as organic metals such as dibutyltin dilaurate and dibutyltin oxide, and metal alkoxides such as tetrabutyl titanate. The amount of such a catalyst added is preferably 0.01 to 1.00% by mass relative to the total amount of raw materials.

  The amorphous polymer B has a weight average molecular weight (Mw) of 5,000 to 1,000,000, preferably 7,000 to 500,000 by molecular weight measurement by gel permeation chromatography (GPC) method of tetrahydrofuran (THF) soluble content. More preferably. The number average molecular weight (Mn) is preferably from 2000 to 10,000, and the molecular weight distribution Mw / Mn is preferably from 1.5 to 100, more preferably from 2 to 60. When the amorphous polymer B has a weight average molecular weight of less than 5,000 or a number average molecular weight of less than 2,000, it is effective for low-temperature fixability but deteriorates the hot offset resistance. In some cases, the storage stability such as toner blocking due to the decrease in toner may be adversely affected. On the other hand, when the weight average molecular weight of the amorphous polymer B exceeds 1,000,000 or the number average molecular weight exceeds 10,000, the hot offset resistance can be sufficiently provided, but the low-temperature fixability is lowered and the crystals present in the toner are also reduced. This may hinder the storability of the protective polyester phase and thus adversely affect document preservation. Therefore, by setting the weight average molecular weight to 5,000 to 1,000,000 or the number average molecular weight to 2,000 to 10,000, it becomes easy to achieve both low-temperature fixability, hot offset resistance, and document storage stability.

  In the present invention, the molecular weight of the resin used is determined by measuring THF solubles using a TOSOH column / TSKgel Super HM-M (15 cm) using a TOSOH GPC / HLC-8120 and a monodisperse polystyrene. The molecular weight was calculated using a molecular weight calibration curve prepared with a standard sample.

  Further, the acid value of the polyester resin (mg number of KOH necessary for neutralizing 1 g of the resin) makes it easy to obtain the molecular weight distribution as described above, and it is easy to ensure the granulation property of the toner particles by the emulsion dispersion method. In addition, the environmental stability (stability of chargeability when the temperature and humidity change) of the obtained toner is easy to keep good, and the like, it is preferably 1 to 30 mg KOH / g. The acid value of the polyester resin can be adjusted by controlling the carboxyl group at the terminal of the polyester according to the blending ratio of the raw polyhydric carboxylic acid and polyhydric alcohol and the reaction rate. Or what has a carboxyl group in the principal chain of polyester is obtained by using trimellitic anhydride as a polyvalent carboxylic acid component.

  Next, the amorphous polymer C will be described. As the amorphous polymer C, a known amorphous polymer can be used, and a styrene acrylic resin can also be used. Examples of monomers that can be used in this case include styrenes such as styrene, parachlorostyrene, and α-methylstyrene: methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, and lauryl acrylate. , Esters having a vinyl group such as 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, and the like: Vinyl nitriles such as acrylonitrile and methacrylonitrile: Vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether: Vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl isopropenyl ketone: Polyolefins such as ethylene, propylene and butadiene: Single amount And a copolymer obtained by combining two or more of these, or a mixture thereof. Furthermore, epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, etc., non-vinyl It is also possible to use a condensation resin, a mixture of these with the vinyl resin, or a graft polymer obtained when a vinyl monomer is polymerized in the presence of these resins. The amorphous polymer C is preferably an amorphous polyester resin.

  When the amorphous polymer C is produced using a vinyl monomer, a resin fine particle dispersion can be produced by carrying out emulsion polymerization using an ionic surfactant or the like. In the case of a resin, if it is oily and dissolves in a solvent having a relatively low solubility in water, the resin is dissolved in those solvents and dissolved in water with a disperser such as a homogenizer together with an ionic surfactant or polymer electrolyte. The resin fine particle dispersion can be prepared by dispersing the fine particles in the solution and then heating or reducing the pressure to evaporate the solvent.

  When the amorphous polymer C is an amorphous polyester, the resin particle dispersion can be easily prepared by adjusting the acid value of the resin and emulsifying and dispersing in water with a dispersing machine such as a homogenizer using a neutralized amine. It is advantageous in that it can be prepared.

The particle size of the resin fine particle dispersion of the amorphous polymer C thus obtained can be measured, for example, with a laser diffraction particle size distribution analyzer (LA-700, manufactured by Horiba, Ltd.).
The glass transition temperature of the amorphous polymer C used in the present invention is preferably 35 to 100 ° C., and more preferably 50 to 80 ° C. from the viewpoint of the balance between storage stability and toner fixing property. preferable. If the glass transition temperature is less than 35 ° C., the toner may be blocked during storage or in a developing machine (a phenomenon in which toner particles are aggregated into a lump). On the other hand, if the glass transition temperature exceeds 100 ° C., the toner fixing temperature may increase.

Moreover, it is preferable that the softening point of the amorphous polymer C is 80-130 degreeC, More preferably, it is 90-120 degreeC. If the amorphous polymer C has a softening point of less than 80 ° C., the toner and the image stability of the toner after fixing and storage may deteriorate. On the other hand, when the softening point exceeds 130 ° C., the low-temperature fixability may be deteriorated.
In the present invention, the softening point of the amorphous polymer C is measured using a flow tester (manufactured by Shimadzu Corp .: CFT-500C), preheating: 300 ° C. at 80 ° C., plunger pressure: 0.980665 MPa, die size: 1 mmφ × 1 mm, temperature increase rate: An intermediate temperature between the melting start temperature and the melting end temperature under the condition of 3.0 ° C./min.

  Next, the amorphous polymer external additive C will be described. As the constituent material of the amorphous polymer external additive D, a known resin material can be used similarly to the amorphous polymer B, but an amorphous polyester resin is particularly preferable.

  The glass transition temperature of the amorphous polymer external additive D is preferably 50 to 100 ° C., and more preferably 60 to 80 ° C. from the viewpoint of the balance between storage stability and toner fixing property. If the glass transition temperature is less than 50 ° C., the toner may block (a phenomenon in which toner particles aggregate and become agglomerates) during storage at 60 ° C. or in a high-temperature stress developing machine. On the other hand, if the glass transition temperature exceeds 100 ° C., the toner fixing temperature may increase.

  The amorphous polymer external additive D is used by being externally added to the toner base particles. The particle diameter of the amorphous polymer external additive D is from about 0.1 μm in volume average diameter, and in the same manner as in a normal wet process toner. Those having a volume average diameter of about 5 μm or those having a volume average diameter of about 1 to 5 μm after pulverization and particle size adjustment can be used. The volume average particle diameter of the amorphous polymer external additive D is preferably 0.3 to 3 μm, more preferably 0.3 to 1 μm.

  It is preferable that the amorphous polymer external additive D has an amorphous shape because the contact area with the mother particle is larger than the spherical shape. Examples of the index indicating this include the shape factor SF1 of the particle obtained by shape observation with Luzex, and the index preferably satisfies the relationship of 125 ≦ SF1 ≦ 145. The shape factor SF1 can be obtained in the same manner as the toner shape factor SF1 described later.

  The glass transition temperature (Tg) of the amorphous polymer external additive D is preferably 55 ° C. or higher, more preferably 60 ° C. or higher, and further preferably 65 ° C. or higher.

  Here, the crystalline resin A, the amorphous polymer B, the amorphous polymer C, and the amorphous polymer external additive D described above are selected so as to satisfy the above formula (1). For example, the monomer type and amount used are adjusted so that the above SP value relationship is satisfied.

  Next, the release agent E will be described. The release agent E is not particularly limited as long as it is a known release agent. For example, natural wax such as carnauba wax, rice wax, candelilla wax, low molecular weight polypropylene, low molecular weight polyethylene, sasol wax, Examples include, but are not limited to, synthesis of microcrystalline wax, Fischer-Tropsch wax, paraffin wax, montan wax, and the like, or ester-based waxes such as mineral / petroleum wax, fatty acid ester, and montanic acid ester. Moreover, these mold release agents may be used individually by 1 type, and may be used together 2 or more types.

  The melting point of the release agent E is preferably 50 ° C. or higher, and more preferably 60 ° C. or higher, from the viewpoint of storage stability. Moreover, it is preferable that it is 110 degrees C or less from a viewpoint of offset resistance, and it is more preferable that it is 100 degrees C or less.

  The content of the release agent E in the toner is preferably in the range of 1 to 30 parts by mass, more preferably in the range of 2 to 20 parts by mass with respect to 100 parts by mass of the binder resin. preferable. If the content of the release agent E is less than 1 part by mass, there is no effect of adding the release agent, and hot offset at a high temperature may be caused. On the other hand, if it exceeds 30 parts by mass, the chargeability is adversely affected, and the mechanical strength of the toner is reduced. Therefore, the toner is easily destroyed by stress in the developing machine, and may cause carrier contamination. Further, when used as a color toner, a domain tends to remain in a fixed image, which may cause a problem that OHP transparency is deteriorated.

  Next, other constituent materials will be described. The colorant used in the toner of the present invention is not particularly limited as long as it is a known colorant, and examples thereof include carbon black such as furnace black, channel black, acetylene black, and thermal black, bengara, bitumen, and titanium oxide. Inorganic pigments, fast yellow, disazo yellow, pyrazolone red, chelate red, brilliant carmine, para brown and other azo pigments, copper phthalocyanine, metal-free phthalocyanine and other phthalocyanine pigments, flavantron yellow, dibromoanthrone orange, perylene red, quinacridone red, Examples include condensed polycyclic pigments such as dioxazine violet, chrome yellow, hansa yellow, benzidine yellow, sren yellow, quinoline yellow, permanent orange GTR, Lozon Orange, Vulcan Orange, Watch Young Red, Permanent Red, Dupont Oil Red, Rissor Red, Rhodamine B Lake, Lake Red C, Rose Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Phthalocyanine Green, Malachite Green Oxalate, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 122, C.I. I. Pigment 57: 1, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 74, C.I. I. Pigment blue 15: 1, C.I. I. Examples thereof include various pigments such as CI Pigment Blue 15: 3, and these can be used alone or in combination of two or more.

  In the toner of the present invention, the content of the colorant is preferably 1 to 30 parts by mass with respect to 100 parts by mass of the binder resin. Alternatively, a surface-treated colorant may be used if necessary. It is also effective to use a pigment dispersant. By appropriately selecting the type of the colorant, yellow toner, magenta toner, cyan toner, black toner and the like can be obtained.

Various components such as an internal additive, a charge control agent, inorganic powder (inorganic fine particles), and organic fine particles can be further added to the toner of the present invention as necessary.
Examples of the internal additive include metals such as ferrite, magnetite, reduced iron, cobalt, nickel, and manganese, alloys, and magnetic materials such as compounds containing these metals.
Examples of the charge control agent include quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments.

  The inorganic powder is added mainly for the purpose of adjusting the viscoelasticity of the toner. For example, silica, alumina, titania, calcium carbonate, magnesium carbonate, calcium phosphate, cerium oxide and the like are listed in detail below. And all inorganic fine particles used as external additives on the toner surface.

In addition to the amorphous polymer external additive D on the toner surface of the present invention, the following inorganic fine particles and organic fine particles are added to improve powder flowability and chargeability. .
Examples of the inorganic fine particles include silica, alumina, titanium oxide, metatitanic acid, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, and diatomaceous earth. , Cerium chloride, bengara, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, zirconium oxide, silicon carbide, silicon nitride and the like. Among them, silica fine particles and titanium oxide fine particles are preferable, and hydrophobized fine particles are particularly preferable.

The inorganic fine particles are generally used for the purpose of improving fluidity. The primary particle diameter of the inorganic fine particles is preferably 1 to 200 nm, and the addition amount is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the toner.
The organic fine particles are generally used for the purpose of improving cleaning properties and transfer properties, and specifically include polystyrene, polymethyl methacrylate, polyvinylidene fluoride, and the like.

  Next, characteristics of the toner of the present invention will be described. The toner (toner mother particles) of the present invention has a divided particle size distribution measured using a measuring instrument such as Coulter Counter TAII (manufactured by Nikka Kisha Co., Ltd.), Multisizer II (manufactured by Nikka Kisha Co., Ltd.), or the like. For the particle size range (channel), the cumulative distribution is drawn from the small diameter side to the volume and number, respectively, the particle size that becomes 16% cumulative is the volume D16%, the particle size that becomes 50% cumulative is the volume D50% cumulative 84%. When the particle diameter is defined as volume D84%, the volume average particle size distribution index (GSDv) calculated from D84% / D16% is preferably 1.15 to 1.30, and preferably 1.15 to 1.30. More preferably, it is 25.

  The absolute charge of the toner of the present invention is preferably 20 to 65 μC / g, more preferably 25 to 55 μC / g. If the charge amount of the toner of the present invention is less than 20 μC / g, background stains (fogging) may occur easily, and if it exceeds 65 μC / g, the image density may decrease easily.

The shape factor SF1 of the toner obtained according to the present invention should satisfy the range of 100 to 140, preferably 120 to 140, from the viewpoint of image formability. This shape factor SF1 is obtained by taking toner particles dispersed on a slide glass or an optical microscope image of the toner into a Luzex image analyzer through a video camera, obtaining the maximum length and projected area of 50 or more toners, and using the following formula: It is obtained by calculating and obtaining the average value.
Formula: SF1 = (ML ² / A) × (π / 4) × 100
In the above formula, ML represents the absolute maximum length of the toner particles, and A represents the projected area of the toner particles.

  By satisfying the characteristics of the respective toners described above, low-temperature fixing is possible, and even in low-speed to high-speed processes, there is little variation in adhesion of a fixed image to a fixing sheet in oil-less fixing and excellent blocking properties. An electrostatic charge developing toner can be obtained.

-Toner production method-
In the toner of the present invention, the toner base particles are contained in an acidic or alkaline aqueous medium such as an agglomeration and coalescence method, a suspension polymerization method, a solution suspension granulation method, a solution suspension method, and a solution emulsion aggregation method. The toner is preferably produced by a wet production method for producing toner particles, but is preferably produced by an aggregation coalescence method.
The aggregation coalescence method suppresses the disruption of the ion balance of the aggregation system and makes it easy to control the aggregation rate.In the suspension polymerization method, it suppresses the occurrence of polymerization inhibition, and particularly makes it easy to control the particle diameter. In the dissolution suspension granulation method and the dissolution emulsification aggregation method, it is possible to stabilize particles during granulation and emulsification.

  When the aggregation coalescence method is used, the toner base particles include at least a crystalline resin A fine particle dispersion in which the crystalline resin A fine particles are dispersed and an amorphous polymer B fine particle dispersion in which the amorphous polymer B fine particles are dispersed. A mixed dispersion is prepared by mixing, and a polymer of at least one metal salt containing polyaluminum chloride is added thereto, and the mixed dispersion is measured with a differential scanning calorimeter. After forming the aggregated particles at a temperature lower than the endothermic peak temperature, an aggregated fine particle dispersion manufacturing step for manufacturing an aggregated fine particle dispersion in which the aggregated particles are aggregated and grown, Attaching step of adhering amorphous polymer C fine particles to the surface of the agglomerated fine particles by adding and mixing an amorphous polymer C fine particle dispersion in which fine particles are dispersed, and an agglomerated fine particle dispersion liquid having undergone the adhering step By the pH basic, the stopping the growth of the aggregated particles, and a step coalescence to coalescence by heating it. Then, by adding external amorphous polymer additive D to the obtained toner base particles, the toner of the present invention is obtained.

In the aggregated fine particle dispersion manufacturing step, the polymer of at least one metal salt added when mixing each dispersion is a polymer of a tetravalent aluminum salt, or the polymer of the metal salt is 4 It is preferable that it is a mixture of a valent aluminum salt polymer and a trivalent aluminum salt polymer. Specifically, these polymers include inorganic metal salts such as calcium nitrate, or inorganic metals such as polyaluminum chloride. Examples thereof include a salt polymer. In the present invention, the polymer of the metal salt is preferably polyaluminum chloride.
The metal salt polymer is preferably added so that the concentration in the aggregated fine particle dispersion is 0.11 to 0.25% by mass.

In the production step of the aggregated fine particle dispersion, when the colorant and the release agent E are included, first, the crystalline resin A fine particle dispersion, the amorphous polymer B fine particle dispersion, the colorant fine particle dispersion, and the release agent E are used. Prepare a particle dispersion.
The crystalline resin A fine particle dispersion is heated by a known phase inversion emulsification or a melting point or higher and emulsified by mechanical shearing force. At this time, an ionic surfactant may be added or the emulsion may be stabilized by self-neutralization using a neutralized amine.

  The amorphous polymer B fine particle dispersion is preferably carried out in the same manner as in the production of the crystalline resin A fine particle dispersion. However, when the amorphous polymer B is capable of emulsion polymerization such as a styrene acrylic resin. It is also preferable to adjust the amorphous polymer B fine particles prepared by emulsion polymerization or the like by dispersing them in a solvent using an ionic surfactant.

  The colorant particle dispersion uses an ionic surfactant opposite in polarity to the ionic surfactant used in the preparation of the resin fine particle dispersion, and the colorant particles of a desired color such as blue, red, and yellow are used as a solvent. It is preferable to adjust by dispersing in.

  The release agent E particle dispersion is prepared by adding and dispersing the release agent E in water together with an ionic surfactant, a polymer electrolyte such as a polymer acid or a polymer base, heating the mixture to a temperature higher than the melting point and strong shearing. It is adjusted by making fine particles with a homogenizer or pressure discharge type disperser.

  Next, a mixed dispersion is prepared by mixing the crystalline resin A fine particle dispersion, the amorphous polymer B fine particle dispersion, the colorant particle dispersion, and the release agent E fine particle dispersion. A temperature lower than the endothermic peak temperature of the crystalline resin A fine particles when the mixed dispersion is measured with a differential scanning calorimeter (preferably 40 to 60). Then, the aggregated particles are aggregated and grown to prepare an aggregated fine particle dispersion in which aggregated particles (core aggregated particles) having a diameter substantially close to a desired toner diameter are dispersed.

  In the adhering step, an amorphous polymer C fine particle dispersion in which amorphous polymer C fine particles are dispersed is added to and mixed with the aggregated fine particle dispersion, thereby forming an amorphous high particle on the surface of the aggregated fine particles (core aggregated particles). By attaching molecular C fine particles and forming a surface layer (shell layer) having a desired thickness, aggregated particles (core / shell aggregated particles) having a core / shell structure in which a shell layer is formed on the surface of the core aggregated particles are obtained.

  The particle diameters of the crystalline resin fine particles A, the amorphous polymer B fine particles, the amorphous polymer fine particles C, the colorant fine particles, and the release agent E fine particles used in the production process of the aggregated fine particle dispersion are the toner diameter and In order to make it easy to adjust the particle size distribution to a desired value, it is preferably 1 μm or less, and more preferably in the range of 20 to 300 nm.

  In the aggregated fine particle dispersion manufacturing process, two polar ionic surfactants (dispersants) contained in the crystalline resin A fine particle dispersion, the amorphous polymer B fine particle dispersion, and the colorant fine particle dispersion are used. The amount balance can be shifted in advance. For example, an inorganic metal salt such as calcium nitrate or a polymer of an inorganic metal salt such as polyaluminum chloride is ionically neutralized and heated below the glass transition temperature of the first resin fine particles to agglomerate the core. Particles can be made.

In such a case, in the adhering step, the resin fine particle dispersion treated with the dispersant having the polarity and the amount so as to compensate for the balance between the two polar dispersants is put into the solution containing the core aggregated particles. The core / shell aggregated particles can be prepared by adding and slightly heating the amorphous polymer C fine particles used in the adhesion step slightly below the glass transition temperature if necessary.
The agglomerated fine particle dispersion manufacturing process and the adhering process may be repeated in a plurality of stages.

  In the fusion / unification step, the agglomerated fine particle dispersion (core / shell agglomerated particle dispersion) obtained through the adhering step has a basic pH (preferably pH 9 to 10) so that the agglomerated fine particles are dispersed. Further, in the dispersion, the melting point of the crystalline resin A contained in the core / shell aggregated particles, and the glass transition temperature of the mixture of the amorphous polymer B and C fine particles (the type of the resin is In the case of two or more types, toner mother particles can be obtained by fusing and coalescing by heating above the glass transition temperature of the resin having the highest glass point transition temperature) and cooling (preferably up to 40 ° C. or less). .

  Furthermore, desired toner base particles are obtained through an arbitrary washing step, solid-liquid separation step, and drying step. In the washing step, it is preferable to sufficiently perform substitution washing with ion-exchanged water from the viewpoint of chargeability. The solid-liquid separation step is not particularly limited, but suction filtration, pressure filtration, and the like are preferably used from the viewpoint of productivity. On the other hand, the drying process is not particularly limited, but freeze drying, flash jet drying, fluidized drying, vibration fluidized drying and the like are preferably used from the viewpoint of productivity.

  Thereafter, the amorphous external additive D is mixed with the toner base particles, and the amorphous external additive D can be externally added to the toner base particles by, for example, stirring with a Henschel mixer or a V blender.

  Hereinafter, the electrostatic charge image developer of the present invention will be described. The electrostatic image developer of the present invention may be applied as the one-component developer of the toner of the present invention, or may be applied as a two-component developer containing the toner carrier and toner of the present invention. Hereinafter, the two-component developer which is the electrostatic charge image developer of the present invention will be described.

  The carrier that can be used in the two-component developer is not particularly limited, and a known carrier can be used. For example, a resin-coated carrier having a resin coating layer on the surface of the core material can be exemplified. Further, a resin-dispersed carrier in which a conductive material or the like is dispersed in a matrix resin may be used.

  Coating resins and matrix resins used for carriers include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic. Examples thereof include, but are not limited to, acid copolymers, straight silicone resins composed of organosiloxane bonds or modified products thereof, fluororesins, polyesters, polycarbonates, phenol resins, and epoxy resins.

  Examples of the conductive material include metals such as gold, silver and copper, carbon black, titanium oxide, zinc oxide, barium sulfate, aluminum borate, potassium titanate, tin oxide, and carbon black. It is not limited.

Examples of the core material of the carrier include magnetic metals such as iron, nickel, and cobalt, magnetic oxides such as ferrite and magnetite, and glass beads. It is preferable.
The volume average particle diameter of the core material of the carrier is preferably in the range of 10 to 500 μm, and more preferably in the range of 30 to 100 μm.

  In order to coat the surface of the core material of the carrier with a resin, there may be mentioned a method of coating with a coating layer forming solution in which the coating resin and, if necessary, various additives are dissolved in an appropriate solvent. The solvent is not particularly limited and may be appropriately selected in consideration of the coating resin to be used, coating suitability, and the like.

  Specific resin coating methods include an immersion method in which the carrier core material is immersed in the coating layer forming solution, a spray method in which the coating layer forming solution is sprayed onto the surface of the carrier core material, and the carrier core material is fluidized air. And a kneader coater method in which the carrier core material and the coating layer forming solution are mixed in a kneader coater and the solvent is removed in a kneader coater.

  The mixing ratio (mass ratio) of the electrostatic image developing toner of the present invention and the carrier in the two-component developer is preferably in the range of toner: carrier = 1: 100 to 30: 100, 3: 100. The range of about 20: 100 is more preferable.

  The image forming method of the present invention will be described below. The image forming method of the present invention includes a latent image forming step of forming an electrostatic latent image on a latent image carrier, and a developing step of developing the electrostatic latent image with a developer containing toner to form a toner image. , A transfer step of transferring the toner image onto a transfer material to form a transfer image, and a fixing step of fixing the transfer image. The toner for developing an electrostatic latent image of the present invention (or the electrostatic charge image developer of the present invention) is applied as the toner. Each of these steps can be performed using each known electrophotographic member.

  Next, the image forming method of the present invention will be specifically described with reference to the drawings. FIG. 1 is a schematic configuration diagram showing an example of an image forming apparatus preferably used in the image forming method of the present invention.

  In FIG. 1, 1 is a heat fixing roller, 2 is a pressure roller, 3 is a heating source, 11 is a photosensitive member (latent image carrier), 12 is a roller charger, 13 is an exposure device, and 14a is a developer (cyan). , 14b is a developer equipped with a developer (magenta), 14c is a developer equipped with a developer (yellow), 14d is a developer equipped with a developer (black), and 14a is a developing device. , 15 is an intermediate transfer member, 16 is a cleaner, 17 is a light static eliminator, 18a, 18b and 18c are spindle rollers, 19 is a transfer roller, and 20 is a transfer target (electrophotographic transfer paper of the present invention). .

The image forming apparatus shown in FIG. 1 includes a roller charger 12, an exposure device 13, and cyan, magenta, yellow, and black developers around a photosensitive member 11 that can rotate in the direction of arrow R in a clockwise direction. The developing device 14 incorporating the developing devices 14a, 14b, 14c, and 14d, the belt-like intermediate transfer member 15, the cleaner 16, and the light neutralizer 17 are arranged in this order.
The intermediate transfer member 15 is stretched by support shaft rollers 18a, 18b, and 18c arranged on the inner peripheral surface thereof, and is rotatable in the direction of arrow P. The support roller 18 a is in pressure contact with the photoreceptor 11 via the intermediate transfer member 15. The support roller 18 c is in pressure contact with the transfer roller 19 via the intermediate transfer member 15.

  In addition, the contacted portion between the outer peripheral surface of the intermediate transfer member 15 and the transfer roller 19 allows the transfer target 20 to be inserted in the arrow Q direction. A heat roller fixing device including a heat fixing roller 1 and a pressure roller 2 in pressure contact with the outer peripheral surface of the intermediate transfer body 15 and the transfer roller 19 is disposed on the arrow Q direction side. The transferred body 20 that has passed through the contact portion between the heat transfer roller 1 and the pressure roller 2 and the contact portion between the outer peripheral surface of the intermediate transfer member 15 and the transfer roller 19 can be inserted in the arrow Q direction. .

  Image formation using the image forming apparatus shown in FIG. 1 is performed as follows. First, the surface of the photoconductor 11 rotating in the direction of arrow R is charged by the roller charger 12. A latent image is formed on the charged portion of the surface of the photoconductor 11 by exposing the surface of the photoconductor 11 with irradiation light L emitted from the exposure device 13 based on image information corresponding to each color of cyan, magenta, and yellow. The latent image formed on the surface of the photoconductor 11 is developed by developing units 14a, 14b, 14c, and 14d built in the developing device 14, and a toner image is formed for each color. The developed toner image is transferred onto the outer peripheral surface of the belt-like intermediate transfer member 15.

  The toner image transferred onto the outer peripheral surface of the intermediate transfer member 15 is transferred to the transfer roller 19 which is in pressure contact with the support roller 18 c via the intermediate transfer member 15 as the intermediate transfer member 15 advances in the arrow P direction. Move between and. When the toner image on the outer peripheral surface of the intermediate transfer member 15 passes through a contact portion (nip portion) between the support roller 18c and the transfer roller 19 that is in pressure contact with the intermediate transfer member 15, this nip. The portion is transferred onto the transfer target 20 inserted in the direction of arrow Q. The toner image transferred onto the transfer target 20 is fixed on the transfer target 20 when the transfer target 20 passes through the contact portion between the heat fixing roller 1 and the pressure roller 2 in the direction of arrow Q. An image is formed.

  The photosensitive member 11 transfers the toner image onto the outer peripheral surface of the intermediate transfer member 15 and then rotates in the direction of arrow R. The toner remaining on the photosensitive member 11 is removed by the cleaner 16, and the photosensitive member 11 is moved onto the photosensitive member 11. The remaining residual charge is neutralized by the light neutralizer 17 to prepare for the next image formation.

  Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto. In this example, various measurements were performed by the following measurement methods in addition to the measurement methods already described.

-Particle size, particle size distribution-
When the particle diameter to be measured is 2 μm or more, a Coulter Counter TA-II type (manufactured by Beckman-Coulter) is used as a measuring device, and an electrolyte is ISOTON-II (manufactured by Beckman-Coulter). Was measured.

  As a measuring method, 0.5 to 50 mg of a measurement sample was added to 2 ml of a 5% aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate as a dispersant, and this was added to 100 to 150 ml of the electrolytic solution. The electrolytic solution in which the measurement sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute. Using the Coulter Counter TA-II type, an aperture having an aperture diameter of 100 μm is used. The particle size distribution of particles in the range of 60 μm was measured. The number of particles to be measured was 50,000.

  For the divided particle size range (channel), the measured particle size distribution is drawn from the small diameter side for each volume and number, and the particle size that is 16% cumulative by volume is accumulated by volume average particle size D16v and number. The cumulative number particle diameter of 16% is defined as D16p. Similarly, a particle diameter that is 50% cumulative in volume is defined as a volume average particle diameter D50v, and a particle diameter that is cumulative 50% in number is defined as a number average particle diameter D50p. Similarly, a particle diameter that is 84% cumulative in volume is defined as a volume average particle diameter D84v, and a cumulative particle diameter that is 84% cumulative in number is defined as D84p. The volume average particle diameter is the D50v.

Using these, the volume average particle size distribution index (GSDv) is calculated from (D84v / D16v) ^1/2 , the number average particle size index (GSDp) is calculated from (D84p / D16p) ^1/2 , and the small diameter side number average The particle size index (lower GSDp) is calculated by {(D50p) / (D16p)}.

  On the other hand, when the particle diameter to be measured was less than 2 μm, the particle size was measured using a laser diffraction particle size distribution analyzer (LA-700: manufactured by Horiba, Ltd.). As a measurement method, a sample in a dispersion is adjusted to have a solid content of about 2 g, and ion exchange water is added thereto to make about 40 ml. This is put into the cell until an appropriate concentration is reached, waits for about 2 minutes, and is measured when the concentration in the cell becomes almost stable. The obtained volume average particle diameter for each channel was accumulated from the smaller volume average particle diameter, and the volume average particle diameter was determined to be 50%.

  When measuring powders such as external additives, 2 g of a measurement sample is added to 50 ml of a 5% aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate, and 2 with an ultrasonic disperser (1,000 Hz). A sample was prepared by dispersing for a minute, and the measurement was performed in the same manner as the above dispersion.

-Acid value-
The acid value (AV) was measured as follows. The basic operation conforms to JIS K-0070-1992.
The sample was used after removing the THF-insoluble component of the binder resin in advance, or the soluble component extracted with the THF solvent by the Soxhlet extractor obtained by the above-described measurement of the THF-insoluble component was used as the sample. 1.5 g of the pulverized sample was precisely weighed, and the sample was placed in a 300 ml beaker, and 100 ml of a toluene / ethanol (4/1) mixture was added and dissolved. Potentiometric titration was performed with an ethanol solution of 0.1 mol / l KOH using an automatic titrator GT-100 (manufactured by Dia Instruments). The amount of KOH solution used at this time is A (ml), and a blank is measured at the same time. The amount of KOH solution used at this time is B (ml). From these values, the acid value was calculated by the following formula. In the formula, w is a precisely weighed sample amount, and f is a factor of KOH.
Formula: Acid value (mgKOH / g) = {(A−B) × f × 5.61} / w

-Preparation of crystalline polyester resin dispersion (A)-
After putting 98 parts of dimethyl sebacate, 2 moles of sodium dimethyl-5-sulfonate and 100 moles of ethylene glycol into a heat-dried three-necked flask, 0.3 parts by weight of dibutyltin oxide as a catalyst per 100 parts by weight in total. The air in the container was brought into an inert atmosphere with nitrogen gas by depressurization, and the mixture was stirred and refluxed at 180 ° C. for 5 hours with mechanical stirring. Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 2 hours. When it became viscous, it was air-cooled, the reaction was stopped, and a crystalline polyester resin (A) was synthesized. The weight average molecular weight (Mw) of the obtained crystalline polyester resin (A) was 9700 by molecular weight measurement (polystyrene conversion) by gel permeation chromatography. Further, when the melting point (Tm) of the crystalline polyester resin (A) was measured using a differential scanning calorimeter (DSC) by the above-described measuring method, it showed a clear endothermic peak, and the endothermic peak temperature was 76.1. ° C.

-Crystalline polyester resin (A) 90 parts by mass-Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 1.8 parts by mass-Ion-exchanged water 210 parts by mass Next, the above composition was heated to 100 ° C, After sufficiently dispersing with IKA Ultra Turrax T50, dispersion treatment is performed with a pressure discharge type gorin homogenizer for 1 hour, a crystalline polyester resin dispersion (A having a center diameter of 200 nm and a solid content in 100 parts by mass of 30 parts by mass (A )

-Preparation of crystalline polyester resin dispersion (B)-
To a heat-dried three-necked flask, 98 mol of dimethyl sebacate, 2 mol of dimethyl-5-sulfonate sodium, 100 mol of 1,6-hexanediol, and 0.3 parts by mass of dibutyltin oxide as a catalyst per 100 parts by mass in total. After putting in, the air in the container was brought into an inert atmosphere with nitrogen gas by a depressurization operation, and stirred and refluxed at 180 ° C. for 5 hours by mechanical stirring. Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 4 hours. When it became viscous, it was cooled with air, the reaction was stopped, and a crystalline polyester resin (B) was synthesized. The weight average molecular weight (Mw) of the obtained crystalline polyester resin (B) was 30000 by molecular weight measurement (polystyrene conversion) by gel permeation chromatography. Further, when the melting point (Tm) of the crystalline polyester resin (B) was measured by the above-described measurement method using a differential scanning calorimeter (DSC), it showed a clear endothermic peak, and the endothermic peak temperature was 66 ° C. there were.

-Crystalline polyester resin (B) 90 parts by mass-Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 1.8 parts by mass-210 parts by mass of ion-exchanged water The above composition was then heated to 100 ° C. After sufficiently dispersing with IKA Ultra Turrax T50, dispersion treatment is carried out with a pressure discharge type gorin homogenizer for 1 hour, and a crystalline polyester resin dispersion (B) having a central diameter of 130 nm and a solid content in 100 parts by mass of 30 parts by mass. )

-Preparation of crystalline polyester resin dispersion (C)-
To a heat-dried three-necked flask, 90.5 mol of 1,10-dodecanedioic acid, 2 mol of dimethyl-5-sulfonic acid sodium salt, 7.5 mol of 5-t-butylisophthalic acid, 100 mol of 1,9-nonanediol, After adding 0.3 parts by mass of dibutyltin oxide as a catalyst per 100 parts by mass in total, the air in the container was brought into an inert atmosphere with nitrogen gas by depressurization and stirred at 180 ° C. for 5 hours with mechanical stirring. Reflux was performed. Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 4 hours. When it became viscous, it was cooled with air, the reaction was stopped, and a crystalline polyester resin (C) was synthesized. The weight average molecular weight (Mw) of the obtained crystalline polyester resin (C) was 28000 by molecular weight measurement (polystyrene conversion) by gel permeation chromatography. Further, when the melting point (Tm) of the crystalline polyester resin (C) was measured using a differential scanning calorimeter (DSC) by the above-described measurement method, it showed a clear endothermic peak, and the endothermic peak temperature was 72 ° C. there were.

-Crystalline polyester resin (C) 90 parts by mass-Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku Co., Ltd.) 1.8 parts by mass-Ion-exchanged water 210 parts by mass Next, the above composition was heated to 100 ° C, After sufficiently dispersing with IKA Ultra Turrax T50, dispersion treatment is performed with a pressure discharge type gorin homogenizer for 1 hour, and a crystalline polyester resin dispersion (C) having a central diameter of 300 nm and a solid content in 100 parts by mass of 30 parts by mass. )

-Preparation of crystalline polyester resin dispersion (D)-
In a heat-dried three-necked flask, 95 mol of dimethyl terephthalate, 5 mol of dimethyl-5-sodium phthalate, 100 mol of 1,9-nonanediol, and 0.3 parts by mass of dibutyltin oxide as a catalyst per 100 parts by mass in total. Then, the air in the container was brought into an inert atmosphere with nitrogen gas by depressurization, and stirred and refluxed at 180 ° C. for 5 hours with mechanical stirring. Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and the mixture was stirred for 2 hours. When the mixture became viscous, it was air-cooled, the reaction was stopped, and a crystalline polyester resin (D) was synthesized. The weight average molecular weight (Mw) of the obtained crystalline polyester resin (D) was 4000 by molecular weight measurement (polystyrene conversion) by gel permeation chromatography. Further, when the melting point (Tm) of the crystalline polyester resin (D) was measured by a differential scanning calorimeter (DSC) by the above-described measurement method, it showed a clear endothermic peak, and the endothermic peak temperature was 94 ° C. there were.

-Crystalline polyester resin (D) 90 parts by mass-Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 5.0 parts by mass-Ion-exchanged water 210 parts by mass Next, the above composition was heated to 100 ° C, After sufficiently dispersing with IKA Ultra Turrax T50, dispersion treatment is performed for 1 hour with a pressure discharge type gorin homogenizer, and a crystalline polyester resin dispersion (D) having a center diameter of 320 nm and a solid content in 100 parts by mass of 30 parts by mass. )

-Preparation of amorphous polyester resin (amorphous polymer) (e)-
30 mol of terephthalic acid, 70 mol of fumaric acid, 20 mol of bisphenol A ethylene oxide 2 mol adduct, 80 mol of bisphenol A propylene oxide 2 mol adduct, 5 liters in volume with stirrer, nitrogen inlet tube, temperature sensor, rectifying column After charging the flask and raising the temperature to 190 ° C. over 1 hour and confirming that the reaction system was uniformly stirred, 1.2 parts by mass of dibutyltin oxide was added. Further, while distilling off the water produced, it took 6 hours from the same temperature to increase the temperature to 240 ° C., and continued the dehydration condensation reaction at 240 ° C. for another 3 hours. The acid value was 12.0 mg / KOH, and the weight average molecular weight. An amorphous polyester resin (e) of 9700 was obtained.

Subsequently, the obtained amorphous polyester resin (e) was transferred in a molten state to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.) at a rate of 100 g / min. Separately prepared aqueous medium tank is filled with 0.37 wt% diluted ammonia water diluted with ion-exchanged water with reagent-exchanged water, and heated at 120 ° C with a heat exchanger at a rate of 0.1 liter per minute. The amorphous polyester resin (e) melt was transferred to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.). Amorphous polyester resin (e) having a volume average particle size of 0.16 μm and a solid content in 100 parts by mass of 30 parts by mass, with the rotor rotating at 60 Hz and pressure of 5 kg / cm ^2. An amorphous polyester resin dispersion (e) in which was dispersed was obtained.

-Preparation of amorphous polyester resin (amorphous polymer) dispersion (f)-
100 mol of terephthalic acid, 90 mol of bisphenol A ethylene oxide 2 mol adduct, and 10 mol of cyclohexanedimethanol are charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectifying column, and one hour is required. The temperature was raised to 190 ° C., and after confirming that the reaction system was uniformly stirred, 1.2 parts by mass of dibutyltin oxide was added. Further, while distilling off the generated water, the temperature was increased to 240 ° C. over 6 hours from the same temperature, and the dehydration condensation reaction was continued at 240 ° C. for another 3 hours. The acid value was 9.0 mg / KOH, the weight average molecular weight. An amorphous polyester resin (f) of 9000 was obtained.

Subsequently, the obtained amorphous polymer resin (f) was transferred in a molten state to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.) at a rate of 100 g / min. Separately prepared aqueous medium tank is filled with 0.37 wt% diluted ammonia water diluted with ion-exchanged water with reagent-exchanged water, and heated at 120 ° C with a heat exchanger at a rate of 0.1 liter per minute. The amorphous polyester resin (e) melt was transferred to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.). Amorphous polyester resin (f) having a volume average particle size of 0.20 μm and a solid content of 30 parts by mass of 30 parts by mass, with the rotor rotating at 60 Hz and the pressure being 5 kg / cm ^2. An amorphous polyester resin dispersion liquid dispersion (f) was obtained.

-Preparation of amorphous polyester resin (amorphous polymer) dispersion (g)-
80 mol% terephthalic acid, 20 mol% isophthalic acid, 90 mol% bisphenol A propylene oxide 2-mol adduct, 10 mol% ethylene glycol were placed in a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectification column. After charging, the temperature was raised to 190 ° C. over 1 hour, and after confirming that the inside of the reaction system was uniformly stirred, 1.2 parts by mass of dibutyltin oxide was added. Further, while distilling off the water produced, it took 6 hours from the same temperature to increase the temperature to 240 ° C., and continued the dehydration condensation reaction at 240 ° C. for another 5 hours. The acid value was 10.0 mg / KOH, and the weight average molecular weight. An amorphous polyester resin (g) of 8500 was obtained.

Subsequently, the obtained amorphous polymer resin (g) was transferred in a molten state to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.) at a rate of 100 g / min. Separately prepared aqueous medium tank is filled with 0.37 wt% diluted ammonia water diluted with ion-exchanged water with reagent-exchanged water, and heated at 120 ° C with a heat exchanger at a rate of 0.1 liter per minute. The amorphous polyester resin (e) melt was transferred to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.). Amorphous polyester resin (g) having a volume average particle size of 0.12 μm and a solid content in 100 parts by mass of 30 parts by mass, with the rotor rotating at 60 Hz and pressure of 5 kg / cm ^2. An amorphous polyester resin dispersion (g) in which was dispersed was obtained.

-Preparation of amorphous polymer dispersion (h)-
80 mol of terephthalic acid, 20 mol of isophthalic acid, 90 mol of bisphenol A propylene oxide 2 mol adduct, and 10 mol of ethylene glycol were charged into a 5 liter flask equipped with a stirrer, nitrogen inlet tube, temperature sensor, and rectification column for 1 hour. After confirming that the reaction system was uniformly stirred, 1.2 parts by mass of dibutyltin oxide was added. Further, while distilling off the generated water, it took 6 hours from the same temperature to increase the temperature to 240 ° C., and continued the dehydration condensation reaction at 240 ° C. for another 5 hours. The acid value was 15.0 mg / KOH, and the weight average molecular weight. An amorphous polyester resin (h) of 30000 was obtained.

Subsequently, the obtained amorphous polymer resin (h) was transferred in a molten state to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.) at a rate of 100 g / min. Separately prepared aqueous medium tank is filled with 0.37 wt% diluted ammonia water diluted with ion-exchanged water with reagent-exchanged water, and heated at 120 ° C with a heat exchanger at a rate of 0.1 liter per minute. The amorphous polyester resin (e) melt was transferred to Cavitron CD1010 (manufactured by Eurotech Co., Ltd.). Amorphous polyester resin (h) having a volume average particle size of 0.13 μm and a solid content in 100 parts by mass of 30 parts by mass, with the rotor rotating at 60 Hz and pressure of 5 kg / cm ^2. An amorphous polyester resin dispersion (h) was obtained.

-Preparation of colorant dispersion-
-Cyan pigment (copper phthalocyanine B15: 3: manufactured by Dainichi Seika) 45 parts by mass-Ionic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 5 parts by mass-Ion-exchanged water 200 parts by mass Mixing and dissolving the above, homogenizer ( IKA Ultra Tarrax) for 10 minutes to obtain a colorant dispersion having a volume average particle size of 168 nm and a solid content in 100 parts by mass of 23.0 parts by mass.

-Preparation of release agent dispersion (j)-
Carnauba wax (melting point: 81 ° C.) 45 parts by mass Cationic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 5 parts by mass 200 parts by mass of ion-exchanged water The above is heated to 95 ° C. to make IKA Ultra Turrax T50 Was sufficiently dispersed in a pressure discharge type gorin homogenizer to obtain a release agent dispersion (j) having a center diameter of 200 nm and a solid content in 100 parts by mass of 20% by mass.

-Preparation of release agent dispersion (k)-
・ Pentaerythritol behenate ester wax (melting point: 84.5 ° C.) 5 parts by mass • Cationic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 5 parts by mass • Ion-exchanged water 200 parts by mass The above is heated to 95 ° C. The dispersion was sufficiently dispersed with IKA Ultra Turrax T50, and then dispersed with a pressure discharge type gorin homogenizer to obtain a release agent dispersion (k) having a center diameter of 220 nm and a solid content in 100 parts by mass of 20%. .

-Preparation of release agent dispersion (l)-
-Paraffin wax HNP-9 (Nippon Seiki, melting point 75 ° C) 45 parts by mass-Cationic surfactant Neogen RK (Daiichi Kogyo Seiyaku) 5 parts by mass-Ion-exchanged water 200 parts by mass After sufficiently dispersing with IKA Ultra Turrax T50, it was dispersed with a pressure discharge type gorin homogenizer to obtain a release agent dispersion (l) having a center diameter of 190 nm and a solid content in 100 parts by mass of 20%.

-Adjustment of amorphous polymer resin particles eD, gD, hD, eDJ for external addition-
The amorphous polymer resins (e), (g), and (h) obtained above were sufficiently washed from the dispersion state with filtration and ion-exchanged water, and then subjected to solid-liquid separation by Nutsche suction filtration. did. This was further redispersed in 1 L of ion exchange water at 40 ° C., and stirred and washed at 300 rpm for 15 minutes. This was further repeated 5 to 10 times, and when the filtrate had a pH of 7.5 and an electrical conductivity of 7.0 μS / cmt, solid-liquid separation was performed using No5A filter paper by Nutsche suction filtration. Vacuum drying was then continued for 12 hours. Then, after crushing with a jet mill and removing coarse powder with an elbow jet, particles (amorphous polymer external additive D) were obtained. Let each be (eD), (gD), and (hD). The volume average particle diameters of these (eD), (gD), and (hD) particles were 0.30 μm, 0.38 μm, and 0.25 μm. The shape factor SF1 was 125, 128, and 125.

  As for the amorphous polymer resin (e), in addition to this, in the solid state of the resin before the dispersion liquid, after crushing with a jet mill and removing coarse powder / fine powder with an elbow jet, a volume average diameter of 2. 5 μm particles (amorphous polymer external additive D) were obtained. Let this be (eDJ). The shape factor SF1 was 144.

  The endothermic peak temperatures TmA of the obtained crystalline resins (A) to (D) and the endothermic peaks when mixed in combinations of the amorphous polymers (e) to (h) (TmAB, TmAC or TmAD in the present invention). Table 1 shows the measurement results of TmAB, TmAC, and TmAD as described above.

  The SP values of the obtained crystalline resins (A) to (D), the SP values of the amorphous polymers (e) to (h), and the difference (absolute value) between the SP values are shown in Table 2 and Table 2. 3 shows.

Example 1
-Production of toner base particles (1)-
Amorphous polymer resin fine particle (g) dispersion 136.7 parts by weight Crystalline resin fine particle (B) dispersion 66.7 parts by weight Colorant dispersion 22.0 parts by weight Release agent dispersion (j ) 50.0 parts by mass The above was sufficiently mixed and dispersed with Ultra Turrax T50 in a round stainless steel flask. Subsequently, 0.20 part by mass of polyaluminum chloride was added thereto, and the dispersion operation was continued with an ultra turrax. The flask was heated to 48 ° C. with stirring in an oil bath for heating. After maintaining at 48 ° C. for 60 minutes, 66.7 parts by mass of the amorphous polymer resin (h) dispersion was gradually added thereto. Thereafter, the pH of the system was adjusted to 9.0 with a 0.5 mol / l sodium hydroxide aqueous solution, and then the stainless steel flask was sealed, and heated to 96 ° C. while continuing to stir using a magnetic seal for 5 hours. Retained.

  After completion of the reaction, the mixture was cooled, filtered, sufficiently washed with ion exchange water, and then subjected to solid-liquid separation by Nutsche suction filtration. This was further redispersed in 1 L of ion exchange water at 40 ° C., and stirred and washed at 300 rpm for 15 minutes. This was repeated five more times, and when the pH of the filtrate became 7.5 and the electric conductivity was 7.0 μS / cmt, solid-liquid separation was performed using No5A filter paper by Nutsche suction filtration. Vacuum drying was then continued for 12 hours. When the particle diameter at this time was measured with a Coulter counter, the volume average diameter D50 was 5.9 μm, and the particle size distribution coefficient GSD was 1.24. Moreover, it was observed that the shape factor SF1 of the particle | grains calculated | required from the shape observation by Luzex was 132.

Further, the viscoelasticity of the toner base particles (1) was measured using a rotating plate type rheometer (RDA 2RHIOS system Ver. 4.3.2, manufactured by Rheometrics Scientific F.E.). . The storage elastic modulus GL (30) at an angular frequency of 1 Hz and 30 ° C. was 3.0 × 10 ⁸ Pa, and the loss elastic modulus GN (90) at 90 ° C. was 2.0 × 10 ⁴ Pa. The measurement was performed by setting the toner to be measured on the sample holder, the temperature rising rate: 1 ° C./min, the frequency: 1 Hz, the distortion: 20% or less, and the detected torque within the range of the measurement compensation value. In addition, the sample holder was properly used for 8 mm and 20 mm as needed.

-Preparation of external additive toner (1)-
Next, an external toner was prepared as follows.
100 parts by mass of the toner base particles (1), 10 parts by mass of (eD), 1.0 part by mass of rutile-type titanium oxide (volume average particle size 20 nm, n-decyltrimethoxysilane treatment), silica (gas phase oxidation method) , Volume average particle size 40 nm, silicone oil treatment) 2.0 parts by mass, higher alcohol ground product (volume average particle size 8 μm) 0.5 parts by mass, using a 5 liter Henschel mixer, peripheral speed 30 m / s After blending for 15 minutes, coarse particles were removed using a sieve having an opening of 45 μm to prepare an externally added toner (1).

(Example 2)
Externally added toner (2) was prepared in the same manner as in Example 1 except that (eD) 10 parts by mass was changed to 0.1 parts by mass.
(Example 3)
Externally added toner (3) was prepared in the same manner as in Example 1 except that (eD) 10 parts by mass was changed to 20 parts by mass.

Example 4
Externally added toner (4) was prepared in the same manner as in Example 1 except that 10 parts by mass of (eD) was changed to 10 parts by mass of (eDJ).

(Example 5)
Externally added toner (5) was prepared in the same manner as in Example 1 except that amorphous polymer g in Example 1 was changed to f and 10 parts by weight of (eD) was changed to 10 parts by weight of (gD) by external addition.

(Example 6)
Externally added toner (6) was prepared in the same manner except that the crystalline resin B of Example 1 was changed to A.

(Example 7)
Externally added toner (7) was prepared in the same manner except that the crystalline resin B of Example 1 was changed to C.

(Example 8)
Externally added toner (8) was prepared in the same manner except that the crystalline resin B of Example 1 was changed to D.

Example 9
Externally added toner (10) was prepared in the same manner as in Example 1 except that 10 parts by mass of (eD) was changed to 25 parts by mass.

(Comparative Example 1)
Externally added toner (9) was prepared in the same manner as in Example 1 except that 10 parts by mass of (eD) was not added.

(Comparative Example 2)
Externally added toner (11) was produced in the same manner as in Example 1 except that 10 parts by mass of (eD) was changed to 10 parts by mass of (hD).

(Comparative Example 3)
Externally added toner (12) was prepared in the same manner except that the amorphous polymer (h) of Example 1 was changed to (e).
(Comparative Example 4)
Externally added toner (13) was prepared in the same manner except that the amorphous polymer (g) of Example 1 was changed to (h).

  The externally added toners (1) to (13) produced as described above were evaluated for minimum fixing temperature, hot offset occurrence temperature, charge amount, and blocking resistance. Table 4 shows a summary of the prepared externally added toners, and Table 5 shows the evaluation results.

(Evaluation of minimum fixing temperature and hot offset occurrence temperature)
A two-component developer was prepared by mixing 9 parts by mass of the externally added toner to be evaluated and 100 parts by mass of ferrite particles (volume average particle diameter: 35 μm) coated with styrene / methyl methacrylate resin. Using a photocopier (Docu Center Color 450 modified machine (Fuji Xerox Co., Ltd.)), a solid image (25 mm × 25 mm) was produced so that the toner weight was 15 g / m 2, and an unfixed image was obtained. JD paper (basis weight 98 g / m2, manufactured by Fuji Xerox Office Supply Co., Ltd.) was used as the evaluation paper.

  Next, the belt nip type fixing device used in the Docu Center Color 450 is taken out and used as an offline fixing device capable of external drive and temperature control, and the fixing temperature is gradually increased between 100 ° C. and 220 ° C. The minimum fixing temperature and hot offset occurrence temperature of the image were evaluated. The minimum fixing temperature is a fixing temperature at which an unfixed solid image (25 mm × 25 mm) is fixed and then bent using a weight with a constant load, and the degree of image defect of that portion is graded to become a certain grade or higher. Was used as an index of low-temperature fixability. On the other hand, the hot offset occurrence temperature is determined by visually determining the presence or absence of an image defect offset to the position of the second round of the period corresponding to the fixing roll diameter of the toner-fixed image, and the temperature at which the image defect occurs is defined as the hot offset occurrence temperature. .

(Evaluation of chargeability)
Weigh 1.5 parts by weight of the externally added toner to be evaluated and 30 parts by weight of ferrite particles (volume average particle diameter 35 μm) coated with styrene / methyl methacrylate resin (20/80 parts by weight ratio) in a glass bottle with a lid. After seasoning for 48 hours under high temperature and high humidity (temperature 32 ° C., humidity 90%), the mixture was stirred and shaken with a turbula mixer for 5 minutes. The charge amount (μC / g) of the toner under this environment was measured with a blow-off charge amount measuring device.

(Evaluation of blocking properties)
Using a powder tester (manufactured by Hosokawa Micron Corporation), 53 μm, 45 μm, and 38 μm openings are arranged in series from the top, and a toner for developing an electrostatic charge image as a sample is placed on the 53 μm sieve with an amplitude of 1 mm. The vibration was applied for 90 seconds, the toner weight on each sieve after vibration was measured, and the weights of 0.5, 0.3, and 0.1 were added and calculated, and the percentage was calculated. The sample toner (1) was left for 24 hours in an environment of 60 ° C./80% RH, and the measurement was performed in an environment of 25 ° C./50% RH. In the present invention, the blocking property can be used without any practical problem if the toner weight after vibration is 30% or less, but is preferably 20% or less, more preferably 10% or less.

(Evaluation of actual filming)
A two-component developer was prepared by mixing 9 parts by mass of the externally added toner to be evaluated and 100 parts by mass of ferrite particles (volume average particle diameter: 35 μm) coated with styrene / methyl methacrylate resin. Using a photocopier (Docu Center Color 450 modified machine (manufactured by Fuji Xerox Co., Ltd.)), 10,000 running tests were performed in an environment of 32 ° C./80% RH. The surface of the photoreceptor was visually observed every 100 sheets to determine whether the toner was filmed.

  From Table 5, it can be seen that by using the electrostatic image developing toners of Examples 1 to 8, it has excellent low-temperature fixability, and it is possible to achieve both chargeability and blocking resistance. On the other hand, in Example 9, since there were too many amorphous polymer external additives D, the actual machine filming (photoconductor filming) was slight at about 5000 sheets, but it occurred.

  On the other hand, in Comparative Example 1, since there is no external additive amorphous resin D that is compatible at the time of fixing and melting to improve the fixing property, the fixing property is inferior. In Comparative Example 2, since the externally added amorphous resin D has a high TmAD and the difference from TmA is as small as 2 ° C., the fixability cannot be fully exhibited due to the compatibility with fixing and melting. Inferior. In Comparative Example 3, the TmA is 66 ° C., the TmAC is as low as 50 ° C., and the toner surface is compatible with the crystalline resin, so that the blocking property is inferior. In Comparative Example 4, TmAB is as high as 63 ° C., and the compatibility between the crystalline resin A and the amorphous resin C is not sufficient, so that the fixability is inferior, and TmAB and TmAC are the same, so that blocking is inferior.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus preferably used in an image forming method of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Photoconductor 12 Roller-type charger 13 Exposure apparatus 14 Developing apparatus 15 Intermediate transfer body 16 Cleaner 17 Optical static eliminators 18a, 18b, 18c Spindle roller 19 Transfer roller

Claims (4)

Toner base particles containing a crystalline resin A and an amorphous polymer B as a binder resin, the surface of which is coated with a surface layer mainly composed of an amorphous polymer C different from the amorphous polymer B;
One or more amorphous polymeric external additives D;
In a toner having
The endothermic peak temperature TmA [° C.] derived from the crystalline resin A, the endothermic peak TmAB [° C.] derived from the crystalline resin A when the crystalline resin A and the amorphous polymer B are mixed, and the crystalline resin The endothermic peak temperature TmAC [° C.] derived from the crystalline resin A when the A and the amorphous polymer C are mixed, and the crystalline resin A when the crystalline resin A and the amorphous polymer external additive D are mixed An electrostatic image developing toner, wherein the derived endothermic peak temperature TmAD [° C.] satisfies the relationship of the following formula (1):
TmAD <TmAB <TmAC ≦ TmA Formula (1)   The toner for developing an electrostatic charge image according to claim 1, wherein the amount of the amorphous polymer external additive D added is 0.1% by mass to 20% by mass with respect to the toner base particles.   An electrostatic latent image developer comprising the electrostatic latent image developing toner according to claim 1 and a carrier. A latent image forming step of forming an electrostatic latent image on the latent image carrier, a developing step of developing the electrostatic latent image with a developer containing toner to form a toner image, and the toner image on a transfer material An image forming method including a transfer step of forming a transfer image by transferring to a transfer step, and a fixing step of fixing the transfer image,
An image forming method, wherein the toner is the electrostatic latent image developing toner according to claim 1.

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