JP2019045782A - Toner and method for manufacturing the same, and colorant master batch - Google Patents

Abstract

To provide a suitable method for manufacturing toner excellent in color developability and fixability.SOLUTION: The method for manufacturing toner includes a master batch manufacturing step, a melting and kneading step, and a pulverization step. The master batch manufacturing step includes manufacturing a colorant master batch containing a colorant, a resin, and nano cellulose powder that is powder of nano cellulose particles. The melting and kneading step includes melting and kneading a toner material containing the colorant master batch to obtain a melted and kneaded product. The pulverization step includes pulverizing the melted and kneaded product to obtain a pulverized product including a plurality of particles. The nano cellulose particles are one or more types of nano cellulose particles selected from the group consisting of a cellulose nanofiber particles and cellulose nanocrystal particles. An amount of the nano cellulose powder in the colorant master batch is 1 mass% or more and 10 mass% or less based on a total mass of the colorant, the resin, and the nano cellulose powder.SELECTED DRAWING: None

Description

  The present invention relates to a toner, a method for producing the same, and a colorant masterbatch.

  In the toner described in Patent Document 1, the toner base particles include a binder resin (binder resin), cellulose nanofibers, a colorant, and a release agent. The binder resin comprises a polyester resin A comprising at least benzenedicarboxylic acid and disproportionated rosin and glycerin, and a polyester resin B comprising at least benzenedicarboxylic acid and a bisphenol A derivative. In the toner mother particles, cellulose nanofibers having a number average fiber length of 50 to 500 μm are internally added.

JP, 2013-44886, A

  However, it is difficult to obtain a toner having excellent color developing ability and fixing ability only by the technique disclosed in Patent Document 1.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide a toner having excellent color forming property and fixing property, a method for producing the same, and a colorant master batch suitable for producing the toner.

  The method for producing a toner according to the present invention includes a masterbatch preparation step, a melt-kneading step, and a grinding step. At the said masterbatch preparation process, the coloring agent masterbatch containing a coloring agent, resin, and the nanocellulose powder which is a powder of nanocellulose particle | grains is produced. In the melt-kneading step, the toner material containing the colorant master batch is melt-kneaded to obtain a melt-kneaded product. In the pulverizing step, the melt-kneaded product is pulverized to obtain a pulverized material containing a plurality of particles. The nanocellulose particles are one or more nanocellulose particles selected from the group consisting of cellulose nanofiber particles and cellulose nanocrystal particles. The amount of the nanocellulose powder in the colorant master batch is 1% by mass or more and 10% by mass or less based on the total mass of the colorant, the resin, and the nanocellulose powder.

  The toner according to the present invention includes a pulverized product of a melt-kneaded product containing a colorant masterbatch. The colorant masterbatch includes a colorant, a resin, and nanocellulose powder which is a powder of nanocellulose particles. The nanocellulose particles are one or more nanocellulose particles selected from the group consisting of cellulose nanofiber particles and cellulose nanocrystal particles. The amount of the nanocellulose powder in the colorant master batch is 1% by mass or more and 10% by mass or less based on the total mass of the colorant, the resin, and the nanocellulose powder.

  The colorant masterbatch according to the present invention comprises a colorant, a resin, and nanocellulose powder which is a powder of nanocellulose particles. The nanocellulose particles are one or more nanocellulose particles selected from the group consisting of cellulose nanofiber particles and cellulose nanocrystal particles. The amount of the nanocellulose powder is 1% by mass or more and 10% by mass or less based on the total mass of the colorant, the resin, and the nanocellulose powder.

  According to the present invention, it is possible to provide a toner excellent in color developability and fixability, a method for producing the same, and a colorant masterbatch suitable for producing the toner.

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

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

  The glass transition point (Tg) is a value measured according to “JIS (Japanese Industrial Standard) K 7 12 1-2012” using a differential scanning calorimeter (“DSC-6220” manufactured by Seiko Instruments Inc.) unless otherwise specified. It is. The endothermic curve (vertical axis: heat flow (DSC signal), horizontal axis: temperature) at the second temperature rise measured with a differential scanning calorimeter, the inflection point (outline with the extrapolation line of the baseline) due to glass transition The temperature (onset temperature) at the intersection of the falling line with the extrapolation line corresponds to Tg (glass transition point). Moreover, the measured value of molecular weight (for example, number average molecular weight) is the value measured using gel permeation chromatography, if it does not specify at all.

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

  The term "main component" of a material means, unless otherwise specified, the component that is most abundant in the material on a mass basis.

  Hereinafter, “system” may be added after the compound name to generically generically refer to the compound and its derivative. When a “system” is added after the compound name to represent a polymer name, it means that the repeating unit of the polymer is derived from the compound or its derivative. In addition, the crystalline polyester resin is described as "crystalline polyester resin", and the non-crystalline polyester resin is simply described as "polyester resin".

  In the present specification, both untreated silica particles (hereinafter referred to as "silica substrate") and silica particles obtained by subjecting a silica substrate to a surface treatment (i.e., surface-treated silica particles) Described as "particles". In addition, silica particles hydrophobized with a surface treatment agent may be described as "hydrophobic silica particles", and silica particles positively charged with a surface treatment agent may be described as "positively chargeable silica particles". Both untreated titanium oxide particles (hereinafter referred to as "titanium oxide substrate") and titanium oxide particles obtained by covering a titanium oxide substrate with a conductive layer (that is, titanium oxide particles provided with conductivity by a coating layer), Described as "titanium oxide particles".

  The toner according to the present embodiment can be suitably used, for example, as a positively chargeable toner for developing an electrostatic latent image. The toner of the present embodiment is a powder including a plurality of toner particles (particles each having a configuration to be described later). The toner may be used as a one-component developer. Further, a two-component developer may be prepared by mixing the toner and the carrier using a mixing device (more specifically, a ball mill or the like). In order to form a high quality image, it is preferable to use a ferrite carrier (more specifically, powder of ferrite particles) as a carrier. Moreover, in order to form a high quality image over a long period of time, it is preferable to use magnetic carrier particles including a carrier core and a resin layer covering the carrier core. In order to impart magnetism to the carrier particles, the carrier core may be formed of a magnetic material (for example, a ferromagnetic substance such as ferrite), or even if the carrier core is formed of a resin in which magnetic particles are dispersed. Good. In addition, magnetic particles may be dispersed in a resin layer that covers the carrier core. In order to form a high quality image, the amount of toner in the two-component developer is preferably 5 parts by mass or more and 15 parts by mass or less with respect to 100 parts by mass of the carrier. The positively chargeable toner contained in the two-component developer is positively charged by the friction with the carrier.

  The toner according to the present embodiment is a powder containing a plurality of toner particles. The toner particles comprise toner base particles and an external additive. The toner base particles contain a binder resin. The toner base particles may optionally contain an internal additive (for example, at least one of a release agent, a colorant, a charge control agent, and a magnetic powder) in addition to the binder resin. The external additive adheres to the surface of the toner base particles.

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

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

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

  The toner according to the present embodiment is a toner for developing an electrostatic latent image having the following configuration (hereinafter referred to as a basic configuration).

(Basic configuration of toner)
The toner contains a pulverized material of the melt-kneaded product containing the NC-containing master batch. The NC-containing masterbatch is a colorant masterbatch having the following constitution.

(Configuration of NC-containing master batch)
The NC-containing masterbatch contains a colorant, a resin, and nanocellulose powder which is a powder of nanocellulose particles. The nanocellulose particles are one or more nanocellulose particles selected from the group consisting of cellulose nanofiber particles and cellulose nanocrystal particles. The amount of nanocellulose powder in the NC-containing master batch is 1% by mass or more and 10% by mass or less based on the total mass of the colorant, the resin, and the nanocellulose powder. Hereinafter, cellulose nanofiber particles may be described as "CNF particles", and cellulose nanofiber powder (that is, powder of CNF particles) may be described as "CNF powder". In addition, cellulose nanocrystal particles may be described as "CNC particles", and cellulose nanocrystal powder (that is, powder of CNC particles) as "CNC powder".

  Cellulose becomes a nanocellulose (fine cellulose fiber with a thickness of 1 nm or more and 100 nm or less) when it is crystallized by hydrogen bonding, and exhibits very high strength. Cellulose nanofibers can be mechanically treated (more specifically, grinding with a bead mill, etc.) or chemically treated (more specifically, TEMPO catalyzed oxidation, carboxymethylation, or the like) from a cellulose raw material (eg, wood) It is a nanocellulose extracted by cationization etc.). Cellulose nanocrystals are obtained by hydrolyzing non-crystalline parts of cellulose raw materials (eg, wood) using a high concentration of mineral acids (eg, strong acids such as hydrochloric acid, sulfuric acid or hydrobromic acid); It is nanocellulose which isolated only a crystal part.

  The inventor of the present invention succeeded in obtaining a toner excellent in color developability and fixability by using the above-mentioned NC-containing master batch. Nanocellulose powders in NC-containing masterbatches tend to promote the dispersion of the colorant. By promoting the dispersion of the colorant in the NC-containing master batch, it is possible to shorten the preparation time of the NC-containing master batch. The material of the NC-containing masterbatch includes nanocellulose powder in addition to the colorant and the resin, so that sufficient shear (specifically, shear stress) can be applied when kneading the material of the NC-containing masterbatch become. The colorant can be finely dispersed by kneading the material with sufficient shear. By reducing the colorant domain diameter in the NC-containing masterbatch, the color developability of the toner is improved.

  In the above-described basic configuration, the pulverized product of the melt-kneaded product containing the NC-containing master batch constitutes a plurality of toner base particles. By using the above-mentioned NC-containing master batch, it becomes easy to finely disperse the colorant in the toner base particles. Therefore, even if the amount of the colorant in the toner base particles is small, it is easy to secure sufficient color development of the toner.

  Even if the toner base particles are heated in the fixing step, the nanocellulose particles do not dissolve. Nanocellulose particles are considered to have the same function as the filler. In addition, when the toner base particles are heated in the fixing step and the toner base particles are melted, the nanocellulose particles act to promote the melting connection of the toner base particles. Nanocellulose particles play a role of bridging between toner mother particles. Cellulose is a material that can be paper and has high affinity to paper. The action of the nanocellulose particles makes it easy to fix the toner on the paper.

  The amount of nanocellulose powder in the above-mentioned NC-containing master batch is 1% by mass or more and 10% by mass or less based on the total mass of the colorant, the resin, and the nanocellulose powder. Excessive nanocellulose powder tends to inhibit the color developability and fixability of the toner.

  The cellulose nanofiber particles and the cellulose nanocrystal particles may each be surface treated (eg, hydrophobized).

  From the viewpoint of productivity, in the NC-containing master batch described above, the nanocellulose powder preferably contains only cellulose nanofiber particles. Further, in order to obtain a toner suitable for image formation, it is preferable that the main component of the cellulose nanofibers is TEMPO oxide of bleached softwood pulp.

  The first method for producing CNF powder includes chemical methods such as TEMPO catalyzed oxidation. By oxidizing cellulose fibers with TEMPO (2,2,6,6-TEtraMethylPiperidine-1-Oxylradical) catalyst to generate electrostatic repulsion between particles, fine needle-like nanocellulose particles are obtained by weak external force. It is possible to get

  A second method for producing CNF powder includes defibration by a physical method. As a physical method, for example, a high pressure homogenizer method, a microfluidizer method, a grinder grinding method, a high shear kneading method, or a ball milling method is preferable. For example, the fibers can be disintegrated by passing through a gap of rubbing media (eg, beads). The fibers can also be fibrillated by sandwiching with a millstone rotating at high speed.

  A third method for producing CNF powder includes an electrical method such as electrospinning. For example, a solution in which fibers are dissolved is placed in a syringe, and a metal plate (collector electrode) is placed to face the needle tip of the syringe. Then, when a high voltage is applied between the needle tip of the syringe and the metal plate, the solution flies from the needle tip of the syringe toward the metal plate, and needle-like nanocellulose particles adhere to the metal plate. The solvent in the solution evaporates during flight, leaving only the needle-like nanocellulose particles on the metal plate.

  A fourth method for producing CNF powder includes a biological method using a microorganism. For example, acetic acid bacteria secrete cellulose fibers to form a cellulose gel (pellicle). Acetic acid bacteria can be used to produce ribbon fibers of cellulose. Moreover, it becomes possible to miniaturize a cellulose fiber by utilizing enzyme decomposition.

  In the nanocellulose powder contained in the above-mentioned NC-containing master batch, the width of CNF particles is preferably 5 nm to 15 nm in number average, and the length of CNF particles is preferably 600 nm to 1000 nm in number average. The “width” and “length” of the particle are values measured based on the two-dimensional projection image (specifically, the SEM photograph) of the particle. The "length" of a particle is the length (long axis diameter) of the particle's major axis, and more specifically, it corresponds to the width of the particle at which the distance between two parallel lines sandwiching the particle is at a maximum. . The “width” of the particle is the particle's minor axis length (minor axis diameter), and more specifically, it is measured on a straight line passing through the middle point of the major axis and orthogonal to the major axis Corresponds to the width of the particle being

  As a method for obtaining the CNF powder having the particle width and the particle length as described above, a method combining the TEMPO catalytic oxidation method and the ball milling method is particularly preferable. Specifically, by finely grinding CNF powder obtained by TEMPO catalytic oxidation method by ball milling, CNF powder having a number average particle width of 5 nm to 15 nm and a number average particle length of 600 nm to 1000 nm can be obtained. . The particle width of CNF powder can be easily controlled based on the amount of TEMPO used. Specifically, the width of the needle-like nanocellulose particles tends to be smaller as the amount of TEMPO used is increased. In addition, the particle length of CNF powder can be easily controlled based on the amount of media and processing time in ball milling. Specifically, as the amount of media increases and as the treatment time (grinding time) increases, the length of the needle-like nanocellulose particles tends to decrease.

  The toner base particles may be toner base particles having no shell layer (hereinafter referred to as non-capsulated toner base particles) or toner base particles provided with a shell layer (hereinafter referred to as capsule toner base particles) It may be The capsule toner mother particles have a toner core containing a binder resin and a shell layer covering the toner core. By forming a shell layer on the surface of non-capsulated toner base particles (toner core), capsule toner base particles can be produced. The shell layer is substantially made of resin. For example, by covering the toner core that melts at a low temperature with a shell layer that is excellent in heat resistance, it is possible to achieve both heat resistance storage stability and low temperature fixability of the toner. The additive may be dispersed in the resin constituting the shell layer. The shell layer may cover the entire surface of the toner core or may partially cover the surface of the toner core.

  In order to improve the fixability of the toner, the toner having the above-described basic composition further includes an external additive which is a powder of external additive particles, and a pulverized product of a melt-kneaded product containing the NC-containing master batch described above. However, a plurality of external toner particles are attached to the surface of the toner mother particles, the toner mother particles are non-capsulated toner mother particles, and the toner mother particles are polyester resin. It is preferable to contain. Cellulose nanofibers and cellulose nanocrystals each have strong affinity with polyester resin. For this reason, the melting and connection of the toner base particles in the fixing step is facilitated by CNF particles and / or CNC particles.

  Non-capsulated toner mother particles can be produced, for example, by a grinding method. The grinding method facilitates the good dispersion of the internal additive in the binder resin of non-capsulated toner base particles. Generally, toners are roughly classified into pulverized toners and polymerized toners (also called chemical toners). The non-capsulated toner base particles obtained by the pulverization method belong to the pulverized toner, and the non-capsulated toner base particles obtained by the aggregation method belong to the polymerized toner.

  In one example of the grinding method, toner materials are first mixed. Subsequently, the obtained mixture is melt-kneaded using a melt-kneading apparatus (for example, a single-screw or twin-screw extruder). Subsequently, the obtained melt-kneaded product is crushed, and the obtained crushed product is classified. Thereby, non-capsulated toner base particles having a desired particle diameter can be obtained.

  The method for producing a toner according to the present embodiment includes a masterbatch preparation step, a melt-kneading step, and a grinding step, which will be described below. In the masterbatch preparation step, the above-mentioned NC-containing masterbatch is prepared. In the melt-kneading step, the toner material containing the NC-containing master batch is melt-kneaded to obtain a melt-kneaded product. In the grinding step, the obtained melt-kneaded product is ground to obtain a ground product containing a plurality of particles. The obtained pulverized material corresponds to toner mother particles (powder).

The NC-containing masterbatch can be produced, for example, by applying a flushing method. In the masterbatch preparation step, a colorant, a resin, and a masterbatch material containing nanocellulose powder which is a powder of nanocellulose particles are melt-kneaded while the temperature is lowered stepwise. It is preferred to obtain a masterbatch (specifically, the NC-containing masterbatch described above). Specifically, a first melt-kneading at a first temperature, a second melt-kneading at a second temperature that is 5 ° C. or more lower than the first temperature, and a temperature 5 ° C. or more lower than the second temperature It is particularly preferable to melt and knead the masterbatch material through a third melt kneader at 3 temperatures. The processing time of each of the first melt-kneading, the second melt-kneading and the third melt-kneading is preferably 10 minutes or more. The total processing time of the first melt-kneading, the second melt-kneading and the third melt-kneading is preferably 120 minutes or less. In a preferable example, the processing time of the first melt-kneading is 30 minutes, the processing time of the second melt-kneading is 30 minutes, and the processing time of the third melt-kneading is 30 minutes. The total processing time of the melt-kneading and the third melt-kneading is 90 minutes (= 30 minutes + 30 minutes + 30 minutes). The difference ΔT _A (= first temperature−second temperature) between the first temperature and the second temperature and the difference ΔT _B (= second temperature−the third temperature) between the second temperature and the third temperature are It is preferable to satisfy the relationship of “ΔT _B −5 ° C. ≦ ΔT _A ≦ ΔT _B + 5 ° C.” (however, 5 ° C. ≦ ΔT _A and 5 ° C. ≦ ΔT _B ). Moreover, it is preferable that difference (DELTA) _TC (= 1st temperature-3rd temperature) of 1st temperature and 3rd temperature is 30 degrees C or less. The first temperature is preferably 105 ° C. or more and 120 ° C. or less. In a preferable example, the first temperature (specifically, the processing temperature of the first melt-kneading) is 110 ° C., and the second temperature (specifically, the processing temperature of the second melt-kneading) is 100 ° C. Specifically, the processing temperature of the third melt-kneading is 90 ° C., ΔT _A is 10 ° C. (= 110 ° C.-100 ° C.), ΔT _B is 10 ° C. (= 100 ° C.-90 ° C.), ΔT _C is 20 ° C. (= 110 ° C.-90 ° C.). In the toner manufacturing method according to this embodiment, the toner material is melt-kneaded through the fourth melt-kneading, the fifth melt-kneading, and the sixth melt-kneading also in the melt-kneading step performed after the masterbatch preparation step. Is particularly preferred. Preferred conditions for the fourth melt-kneading, fifth melt-kneading, and sixth melt-kneading are the same as the first melt-kneading, second melt-kneading, and third melt-kneading, respectively, described above.

  When producing capsule toner mother particles, the method of forming the shell layer is optional. For example, the shell layer can be formed on the surface of the toner core (non-capsulated toner base particles) by in-situ polymerization method, in-liquid curing coating method, or coacervation method.

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

[Suitable polyester resin]
As resin which comprises toner mother particles, polyester resin is preferred, for example.

  The polyester resin comprises one or more polyhydric alcohols (more specifically, aliphatic diols, bisphenols, or tri- or higher alcohols, etc. as shown below) and one or more polyhydric carboxylic acids (more specific) Specifically, it can be obtained by condensation polymerization of a divalent carboxylic acid or a trivalent or higher carboxylic acid or the like as shown below. The polyester resin may also contain repeating units derived from other monomers (ie, monomers that are neither polyhydric alcohol nor polyhydric carboxylic acid).

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

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

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

  Preferred examples of the divalent carboxylic acid include aromatic dicarboxylic acids (more specifically, phthalic acid, terephthalic acid, or isophthalic acid etc.), α, ω-alkanedicarboxylic acids (more specifically, malonic acid) Succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, or 1,10-decanedicarboxylic acid, etc.), a dicarboxylic acid having a side chain attached to α, ω-alkanedicarboxylic acid (more specifically, Alkylsuccinic acid or alkenylsuccinic acid etc.), unsaturated dicarboxylic acids (more specifically, maleic acid, fumaric acid, citraconic acid, itaconic acid or glutaconic acid etc.), or cycloalkanedicarboxylic acids (more specifically) And cyclohexanedicarboxylic acid etc.).

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

  Next, non-capsulated toner base particles (binder resin and internal additives) and external additives will be described in order. Unnecessary components may be omitted depending on the application of the toner. A shell layer may be formed on the surface of non-capsulated toner base particles (toner core) described below to produce capsule toner base particles.

[Toner mother particles: non-capsulated toner mother particles]
(Binder resin)
In the toner base particles, in general, the binder resin occupies most (for example, 60% by mass or more) of the components. For this reason, it is considered that the properties of the binder resin greatly affect the properties of the entire toner matrix particles. By using a plurality of resins in combination as the binder resin, the properties of the binder resin (more specifically, the hydroxyl value, acid value, Tg, Tm, etc.) can be adjusted. When the binder resin has an ester group, a hydroxyl group, an ether group, an acid group or a methyl group, the toner base particles tend to be anionic, and when the binder resin has an amino group, the toner The mother particles are more likely to be cationic.

  Examples of the binder resin include styrene resin, acrylic resin (more specifically, acrylic ester polymer or methacrylic acid ester polymer, etc.), olefin resin (more specifically, polyethylene resin or Polypropylene resin etc.), vinyl chloride resin, polyvinyl alcohol, vinyl ether resin, N-vinyl resin, polyester resin, polyamide resin, or urethane resin is mentioned. Also, a copolymer of each of these resins, that is, a copolymer in which an arbitrary repeating unit is introduced into the above resin (more specifically, a styrene-acrylic acid resin or a styrene-butadiene resin, etc.) is used. May be

  As the binder resin, a polyester resin (see the above-mentioned [preferred polyester resin]) is particularly preferable. Further, the toner base particles may contain a crystalline polyester resin. By incorporating the crystalline polyester resin in the toner base particles, it is possible to impart sharp melt properties to the toner base particles.

  In order to ensure sufficient toner fixability even at high-speed fixing, a glass of a binder resin (in the case where toner mother particles contain a plurality of binder resins, the binder resin is most abundant on a mass basis) The transition point (Tg) is preferably 30 ° C. or more and 65 ° C. or less.

  In order to ensure sufficient toner strength and fixability, the number average molecular weight (Mn) of the polyester resin contained in the toner base particles is preferably 1000 or more and 2000 or less.

(Master Badge)
In the toner having the above-described basic configuration, the toner base particles are a pulverized product of a melt-kneaded product containing a colorant master batch. Specifically, the toner base particles are a pulverized product of a melt-kneaded product containing the above-mentioned NC-containing master batch. The NC-containing masterbatch contains a colorant, a resin, and nanocellulose powder (more specifically, powder of nanocellulose particles).

(Master batch: resin)
Examples of the resin in the NC-containing master batch include styrene resin, acrylic resin (more specifically, acrylic ester polymer or methacrylic acid ester polymer, etc.), olefin resin (more specifically, Polyethylene resin or polypropylene resin, vinyl chloride resin, polyvinyl alcohol, vinyl ether resin, N-vinyl resin, polyester resin, polyamide resin, or urethane resin. Also, a copolymer of each of these resins, that is, a copolymer in which an arbitrary repeating unit is introduced into the above resin (more specifically, a styrene-acrylic acid resin or a styrene-butadiene resin, etc.) is used. May be

  As a resin in the NC-containing masterbatch, a polyester resin (see the above-mentioned [preferred polyester resin]) is particularly preferable. The resin in the NC-containing master batch may be a resin having the same composition as the binder resin described above, or may be a resin having a composition different from the binder resin described above.

(Masterbatch: Colorant)
As the colorant in the NC-containing masterbatch, known colorants can be used in accordance with the color of the toner.

  The toner base particles may contain a black colorant. Examples of black colorants include carbon black. The black colorant may be a colorant toned to black using a yellow colorant, a magenta colorant, and a cyan colorant.

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

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

  The magenta colorant is selected, for example, from the group consisting of condensation azo compounds, diketopyrrolopyrrole compounds, anthraquinone compounds, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perylene compounds. One or more compounds can be used. Examples of magenta colorants include C.I. I. Pigment red (2, 3, 5, 6, 7, 19, 19, 23, 48: 2, 48: 3, 48: 4, 57: 1, 81: 1, 122, 144, 146, 150, 166, 169, 177 184, 185, 202, 206, 220, 221, 254 or 269) can be suitably used.

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

(Masterbatch: Nanocellulose powder)
The nanocellulose powder in the NC-containing masterbatch is preferably a powder containing a plurality of needle-like nanocellulose particles. The nanocellulose particles are one or more nanocellulose particles selected from the group consisting of cellulose nanofiber particles and cellulose nanocrystal particles. As the nanocellulose particles, cellulose nanofiber particles are preferable, and cellulose nanofiber particles whose main component is TEMPO oxide of bleached softwood pulp are particularly preferable.

(Release agent)
The toner base particles may contain a release agent. The release agent is used, for example, for the purpose of improving the fixing property or the offset resistance of the toner. In order to improve the fixing property or the offset resistance of the toner, the amount of the releasing agent is preferably 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the binder resin.

  As the releasing agent, for example, low molecular weight polyethylene, low molecular weight polypropylene (for example, “Biscol (registered trademark) 660P” manufactured by Sanyo Chemical Industries, Ltd.), polyolefin copolymer, polyolefin wax, microcrystalline wax, paraffin wax (for example, , An aliphatic hydrocarbon wax such as Nippon Seiwa Co., Ltd. “HNP-9”, or Fischer-Tropsch wax; an oxide of an aliphatic hydrocarbon wax such as oxidized polyethylene wax or a block copolymer thereof; candelilla Vegetable wax such as wax, carnauba wax, wax wax, jojoba wax, or rice wax; animal wax such as beeswax, lanolin, or spermaceti; mineral wax such as ozokerite, ceresin, or petrolatum; Waxes mainly composed of fatty acid esters such as Ruwakkusu or castor wax; deoxidation, such as carnauba wax, wax portion of the fatty acid esters or all was deoxygenated can be suitably used. One type of release agent may be used alone, or two or more types of release agents may be used in combination.

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

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

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

  In order to suppress the elution of metal ions (for example, iron ions) from the magnetic powder, it is preferable to surface-treat the magnetic powder. In the case where a shell layer is formed on the surface of toner base particles under acidic conditions, when metal ions are eluted on the surface of the toner base particles, the toner base particles are easily fixed to each other. By suppressing the elution of metal ions from the magnetic powder, it is considered that the adhesion between toner base particles can be suppressed.

[External additive]
An external additive (more specifically, a powder containing a plurality of external additive particles) may be attached to the surface of the toner base particles. Unlike the internal additive, the external additive is not present inside the toner base particles, and selectively present only on the surface of the toner base particles (the surface layer of the toner particles).

  For example, the external additive particles can be attached to the surface of the toner base particles by stirring the toner base particles (powder) and the external additive (powder) together. The toner base particles and the external additive particles do not chemically react with each other and physically but not chemically. The bonding strength between the toner base particles and the external additive particles is determined by stirring conditions (more specifically, stirring time, rotational speed of stirring, etc.), particle diameter of external additive particles, shape of external additive particles And the surface condition of the external additive particles.

  In order to sufficiently exhibit the function of the external additive while suppressing the detachment of the external additive particle from the toner particles, the amount of the external additive (when using plural types of external additive particles, they may be used. The total amount of external additive particles) is preferably 0.5 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of toner base particles.

  As external additive particles, inorganic particles are preferable, and particles of silica particles or metal oxides (more specifically, particles of alumina, titanium oxide, magnesium oxide, zinc oxide, strontium titanate, barium titanate, etc.) Particularly preferred. However, as the external additive particles, particles of an organic acid compound such as a fatty acid metal salt (more specifically, zinc stearate etc.) or resin particles may be used. Also, as the external additive particles, composite particles which are composites of plural kinds of materials may be used. The external additive particles may be surface treated. One type of external additive particle may be used alone, or two or more types of external additive particle may be used in combination.

  An embodiment of the present invention will be described. Table 1 shows toners TA-1 to TA-3 and TB-1 to TB-4 (toner for developing electrostatic latent image) according to Examples or Comparative Examples.

In Table 1, "MB-1" to "MB-6" respectively mean master batches MB-1 to MB-6 prepared by the method described later.
In Table 1, "colorant" means an azo pigment (CI Pigment Red (PR) 269: "Red No. 85" manufactured by Dainichi Seika Kogyo Co., Ltd.).
In Table 1, "resin" means polyester resin ("Toughton (registered trademark) NE-410" manufactured by Kao Corporation).
In Table 1, "CNF powder" means a powder of cellulose nanofibers prepared by the method described later.

  Hereinafter, the manufacturing method, evaluation method and evaluation result of the toners TA-1 to TA-3 and TB-1 to TB-4 will be described in order. In addition, in the evaluation which an error produces, the measurement value of a considerable number which an error becomes small enough was obtained, and the arithmetic mean of the obtained measurement value was made into the evaluation value.

[Preparation of materials]
(How to make CNF powder)
In a container (first container), 1.5 L of ion exchange water was placed. After that, in a container, 200 parts by mass of sulfite bleached softwood pulp, 2.0 parts by mass of TEMPO (2,2,6,6-TEtraMethylPiperidine-1-Oxylradical) and 25 parts by mass of sodium bromide in dry weight And dispersed in water. Subsequently, an aqueous solution of sodium hypochlorite at a concentration of 13% by mass is added to the container so that the amount of sodium hypochlorite per 1 g of pulp in the container is 2.5 mmol, and the content of the container is reacted I did. During the reaction, while confirming the pH of the contents of the container, an aqueous solution of sodium hydroxide having a molar concentration of 0.5 M was dropped into the container according to the amount of change in pH to maintain the pH of the container contents at 10.5. . The reaction is judged to be complete when the pH of the contents of the container does not change, and the contents of the container containing the reaction product are subjected to solid-liquid separation (filtration) using a glass filter to obtain a solid (reaction product Got). Thereafter, the obtained solid was re-dispersed in a sufficient amount of ion exchange water and washed with water. Dispersion and filtration were repeated a total of 5 times. As a result, a water-impregnated fibrous body (solids concentration: 25% by mass) was obtained.

  Subsequently, the obtained water-impregnated fiber body and ion-exchanged water were placed in a container (second container) different from the first container to prepare a slurry with a solid content concentration of 2% by mass. . Subsequently, the contents of the container (slurry) were subjected to dispersion treatment using a rotary blade type mixer. Dispersion treatment increased the viscosity of the contents of the container (slurry). During dispersion treatment, ion exchange water is added to the container to keep the viscosity of the container contents (slurry) almost constant, and the solid content concentration of the container contents (slurry) becomes 0.15 mass% Distributed processing ended. As a result, a dispersion (solid content concentration: 0.15% by mass) containing a cellulose fiber body was obtained. The dispersion treatment time was about 5 minutes.

  Subsequently, the obtained dispersion was separated into a float and a sediment by centrifugation to remove the float. Subsequently, the sediment was washed with water and then dried to obtain a dried cellulose fiber body. Subsequently, the dried cellulose fiber body is crushed to obtain a crushed material with a particle width (number average fiber diameter) of about 10 nm and a particle length (number average fiber length) of about 1.5 μm (specifically, a cellulose fiber body Crushed material) was obtained. Hereinafter, the crushed material obtained here is described as "CF crushed material".

  20 g of the crushed CF obtained as described above and 500 g of zirconia beads having a diameter of 0.1 mm were placed in a 1 L polyethylene container, and the container was set in a ball mill. Then, using the ball mill, the contents of the container were subjected to grinding treatment for 2 hours under the condition of a rotational speed of 100 rpm. As a result, the CF crushed material was crushed by a grinding media (zirconia beads) to obtain a CNF powder (that is, a powder of cellulose nanofibers). The particle width (number average fiber diameter) and the particle length (number average fiber length) of the obtained CNF powder were measured. Specifically, an image analysis software (Mitani Corporation) is an SEM image obtained by photographing CNF powder using a field emission scanning electron microscope (FE-SEM) ("JSM-7600F" manufactured by Nippon Denshi Co., Ltd.) The particle width and particle length of the CNF powder were each measured by analysis using “WinROOF” manufactured by Co., Ltd. In the CNF powder, the width of the CNF particles was about 9 nm in number average, and the length of the CNF particles was about 900 nm in number average.

(Preparation method of coloring agent masterbatch)
Colorant (PR 269), resin (Tafton NE-410), CNF powder (powder of cellulose nanofiber particles obtained by the above method) using an FM mixer (manufactured by Japan Coke Industry Co., Ltd.) , Mixed at the ratio shown in Table 1. For example, in the production of masterbatch MB-3, 40.0 parts by mass of a colorant (PR 269), 59.0 parts by mass of a resin (Tuffton NE-410), CNF powder (cellulose nanofibers obtained by the above-mentioned method) It mixed with 1.0 mass part of powder of particle | grains. Moreover, in manufacture of masterbatch MB-1, CNF was not added but 40 mass parts of coloring agents (PR269) and 60 mass parts of resin (Tafton NE-410) were mixed.

Subsequently, the obtained mixture is charged into a 3 L pressure type kneader (manufactured by Moriyama Co., Ltd.), and the first melt-kneading and the second melt-kneading shown below at a rotational speed of 100 rpm using this kneader , And the third melt-kneading was performed in this order.
First melting and kneading: temperature 110 ° C, treatment time 30 minutes (from 0 minutes to 30 minutes)
Second melting and kneading: temperature 100 ° C, treatment time 30 minutes (from 30 minutes to 60 minutes)
Third melt kneading: temperature 90 ° C, treatment time 30 minutes (from 60 minutes start to 90 minutes start)

  A colorant masterbatch (masterbatch MB-1) comprising a colorant and a resin (specifically, a polyester resin) by the above-described melt-kneading (specifically, first melt-kneading, second melt-kneading, and third melt-kneading) MB-6) was obtained. Masterbatches MB-2 to MB-6 each further contained a plurality of CNF particles in addition to the colorant and the resin. Masterbatch MB-1 did not contain CNF particles.

[Method of Manufacturing Toners TA-1 to TA-3 and TB-1 to TB-3]
15 parts by mass of powdery colorant masterbatch (any of masterbatches MB-1 to MB-6 specified for each toner) shown in Table 1 using an FM mixer (manufactured by Japan Coke Industry Co., Ltd.), 80 parts by mass of a polyester resin ("Tafton NE-410" manufactured by Kao Corp.) and 5 parts by mass of paraffin wax ("HNP-9" manufactured by Nippon Seiwa Co., Ltd.) were mixed.

Subsequently, the obtained mixture is introduced into a 3 L pressure type kneader (Moriyama Co., Ltd.), and the fourth melt-kneading and fifth melt-kneading shown below at a rotational speed of 100 rpm using this kneader , And the sixth melt-kneading were performed in this order.
Fourth melt kneading: temperature 110 ° C, treatment time 30 minutes (from 0 minutes start to 30 minutes start)
Fifth melt kneading: temperature 100 ° C, treatment time 30 minutes (from 30 minutes to 60 minutes)
Sixth melting and kneading: temperature 90 ° C, treatment time 30 minutes (from 60 minutes to 90 minutes)

The kneaded material obtained by the above-mentioned melt-kneading (specifically, the fourth melt-kneading, the fifth melt-kneading, and the sixth melt-kneading) was cooled while rolling so that its thickness was about 1.5 mm. Subsequently, the obtained kneaded product was roughly pulverized at a set particle diameter of 1 mm using a pulverizer (“Rotoplex (registered trademark)” manufactured by Hosokawa Micron Corporation). Subsequently, the obtained coarsely pulverized material was pulverized using a mechanical pulverizer ("Turbomill T250" manufactured by Freund Turbo Co., Ltd.). Subsequently, the obtained pulverized material was classified using a classifier (wind classifier using Coanda effect: “Elbow jet EJ-LABO type” manufactured by Nittetsu Mining Co., Ltd.). As a result, toner base particles having a volume median diameter (D ₅₀ ) of 7 μm were obtained.

(External addition process)
Subsequently, 100 parts by mass of toner base particles (powder) obtained as described above using an FM mixer ("FM-10C / I" manufactured by Japan Coke Industry Co., Ltd.), and silica particles (powder) 1 .5 parts by mass and 1.5 parts by mass of titanium oxide particles (powder) were mixed for 5 minutes.

Silica particles are positively chargeable silica particles ("AEROSIL (registered trademark) REA 90" manufactured by Nippon Aerosil Co., Ltd., content: dry silica particles provided with positive chargeability by surface treatment, number average primary particle diameter: 20 nm) there were.
The titanium oxide particles were conductive titanium oxide particles (“EC-100” manufactured by Titanium Kogyo Co., Ltd., base: TiO ₂ particles, coating layer: Sb-doped SnO ₂ layer, volume median diameter: about 0.35 μm) .

  By the above mixing, the external additive (silica particles and titanium oxide particles) adheres to the surface of the toner base particles. Then, it sifted using the sieve of 200 mesh (75 micrometers of mesh openings). As a result, toners containing a large number of toner particles (toners TA-1 to TA-3 and TB-1 to TB-3 shown in Table 1) were obtained.

[Method of Manufacturing Toner TB-4]
In the method of producing toner TB-4, toner base particles were produced without using a masterbatch. Specifically, 6 parts by mass of an azo pigment (CI Pigment Red (PR) 269: "Red No. 85" manufactured by Dainichi Seika Industry Co., Ltd.) using an FM mixer (manufactured by Nippon Coke Industry Co., Ltd.), 84 parts by mass of polyester resin ("Tafton NE-410" manufactured by Kao Corp.), 5 parts by mass of paraffin wax ("HNP-9" manufactured by Nippon Seiwa Co., Ltd.), CNF powder (cellulose obtained by the above-mentioned method) It mixed with 5 mass parts of powder of nanofiber particle | grains.

Subsequently, the obtained mixture is put into a 3 L pressure type kneader (manufactured by Moriyama Co., Ltd.), and the above-mentioned fourth melt-kneading, fifth melt-kneading, under the conditions of rotational speed 100 rpm, using this kneader. And the 6th melt-kneading was performed in this order. Subsequently, the obtained kneaded material was cooled while rolling so that its thickness was about 1.5 mm. Subsequently, the obtained kneaded product was roughly pulverized at a set particle diameter of 1 mm using a pulverizer (“Rotoplex” manufactured by Hosokawa Micron Corporation). Subsequently, the obtained coarsely pulverized material was pulverized using a mechanical pulverizer ("Turbomill T250" manufactured by Freund Turbo Co., Ltd.). Subsequently, the obtained pulverized material was classified using a classifier (wind classifier using Coanda effect: “Elbow jet EJ-LABO type” manufactured by Nittetsu Mining Co., Ltd.). As a result, toner base particles having a volume median diameter (D ₅₀ ) of 7 μm were obtained.

  Thereafter, the above-mentioned external addition step was performed in the same manner as in the method for producing toner TA-1. As a result, the external additive (silica particles and titanium oxide particles) adheres to the surface of the toner base particles. Furthermore, it sifted using the sieve of 200 mesh (75 micrometers of openings). As a result, a toner containing a large number of toner particles (toner TB-4 shown in Table 1) was obtained.

[Evaluation method]
The evaluation method of each sample (toner TA-1 to TA-3 and TB-1 to TB-4) is as follows.

(Preparation of developer for evaluation)
100 parts by mass of a carrier for a developer (carrier for "TASKalfa 5551ci") and 5 parts by mass of a toner (object of evaluation: any of toners TA-1 to TA-3 and TB-1 to TB-4) using a ball mill The mixture was mixed for 30 minutes to prepare a developer for evaluation (two-component developer).

(Preparation of evaluation machine)
As an image forming apparatus for evaluation, a multifunction peripheral ("TASKalfa5551ci" manufactured by KYOCERA Document Solutions, Inc.) was used. In addition, the fixing device removed from the printer ("FS-C5250DN" manufactured by KYOCERA Document Solutions Inc.) having the roller-roller type heat and pressure fixing device is modified so that the fixing temperature can be changed, and the fixing for evaluation is made. Used as an apparatus.

  The developer for evaluation (two-component developer) prepared as described above is loaded into the developing device of the above-mentioned multi-functional peripheral (image forming apparatus for evaluation) to supply toner (target for evaluation: toners TA-1 to TA-3) And any one of TB-1 to TB-4) was loaded into the toner container of the above-mentioned multifunction machine (image forming apparatus for evaluation).

(Coloring)
Using the image forming apparatus for evaluation prepared as described above, under an environment of temperature 23 ° C. and humidity 60% RH, paper (A4 size plain paper: “C ² ” manufactured by Fuji Xerox Co., Ltd.) A solid image (specifically, an unfixed toner image) was formed under the conditions of 267 mm / sec and the toner coverage 0.4 mg / cm ² . Subsequently, the paper on which the unfixed toner image was formed was passed through the above-mentioned fixing device for evaluation. The evaluation fixing device was subjected to a fixing process at a temperature of 170.degree.

Subsequently, the L ^* value, a ^* value, and the like in the CIE 1976 (L ^* , a ^* , b ^* ) color space are applied to the image subjected to the fixing process as described above (specifically, the image formed on paper). And b ^* values were each measured using a reflection densitometer ("SpectroEye (registered trademark)" manufactured by X-Rite). In the CIE 1976 (L ^* , a ^* , b ^* ) color space, lightness is represented by L ^* , and chromaticity indicating hue and saturation is represented by a ^* and b ^* .

The color developability of other toners was evaluated based on the L ^* value, a ^* value, and b ^* value measured for Toner TB-1. Hereinafter, the L ^* value, the a ^* value, and the b ^* value of the toner TB-1 will be referred to as the “reference L ^* value”, the “reference a ^* value”, and the “reference b ^* value”, respectively. Specifically, according to the equation “ΔE ^* = {(L ^* value−reference L ^* value) ² + (a ^* value−reference a ^* value) ² + (b ^* value−reference b ^* value) ² } ^1/2 ” The color difference ΔE ^* of each toner was calculated. The color developability of the toner was evaluated from the measured color gamut and the color difference ΔE ^* . If the color gamut is larger than that of the toner TB-1 and the color difference ΔE ^* is 1.5 or more, it is judged as ○ (good), and the color gamut is smaller than that of the toner TB-1, or If the color difference ΔE ^* was less than 1.5, it was judged as × (not good).

(Fixability)
Using the image forming apparatus for evaluation prepared as described above, under an environment of temperature 23 ° C. and humidity 60% RH, paper (A4 size plain paper: “C ² ” manufactured by Fuji Xerox Co., Ltd.) A solid image (specifically, an unfixed toner image) was formed under the conditions of 267 mm / sec and the toner coverage 0.4 mg / cm ² . Subsequently, the paper on which the unfixed toner image was formed was passed through the above-mentioned fixing device for evaluation. The evaluation fixing device was subjected to a fixing process at a temperature of 160.degree.

  Subsequently, with respect to the image subjected to the fixing process as described above (specifically, the image formed on paper), the image density was measured before and after the rubbing test. Specifically, using a reflection densitometer ("SpectroEye" manufactured by X-Rite Co., Ltd.), the image density (hereinafter referred to as pre-scratching ID) of the image on the paper passed through the fixing device for evaluation was measured. Subsequently, the image on the paper was rubbed back and forth 10 times using a 1 kg weight coated with fabric. Subsequently, a reflection densitometer (SpectroEye) was used to measure the image density of the image on paper (hereinafter referred to as post-abrasion ID). Subsequently, the fixing rate (unit:%) was determined according to the formula “fixing rate = 100 × after rubbing ID / before rubbing ID”. The fixability of the other toners was evaluated based on the fixing rate measured for the toner TB-1 (hereinafter referred to as "reference fixing rate"). Specifically, the fixing index of each toner was calculated according to the formula “fixing index = (fixing ratio of toner) / (reference fixing ratio)”. The fixing property of each toner was determined to be ○ (good) if the fixing index was 1.05 or more, and was determined to be × (not good) if the fixing index was less than 1.05.

[Evaluation results]
Table 2 shows the results of evaluating the color developability and fixability of each of the toners TA-1 to TA-3 and TB-1 to TB-4. The evaluation results shown in Table 2 are the L ^* value, the a ^* value, the b ^* value, the color gamut, and the color difference ΔE ^{* for} color developability, and the fixing index for fixability.

  The toners TA-1 to TA-3 (toners according to Examples 1 to 3) each had the above-described basic configuration. Specifically, each of the toners TA-1 to TA-3 contained a pulverized product of the melt-kneaded product containing the NC-containing master batch. The NC-containing masterbatch contained a colorant, a resin, and a powder of cellulose nanofiber particles. The amount of nanocellulose powder (specifically, powder of cellulose nanofibers) in the NC-containing master batch is 1% by mass or more and 10% by mass or less based on the total mass of the colorant, the resin and the nanocellulose powder (See Table 1).

  As shown in Table 2, the toners TA-1 to TA-3 were excellent in color development and fixation.

  In addition, as a nanocellulose particle in NC containing masterbatch, it replaced with the cellulose nanofiber particle, and when it used the cellulose nanocrystal particle, it became the same evaluation result. That is, the toner having the above-described basic configuration was superior in color developability and fixability to the toner not having the above-described basic configuration.

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

Claims (9)

A masterbatch preparation step of preparing a colorant masterbatch containing a colorant, a resin, and a nanocellulose powder which is a powder of nanocellulose particles;
A melt-kneading step of melt-kneading a toner material containing the colorant master batch to obtain a melt-kneaded product;
Pulverizing the melt-kneaded product to obtain a pulverized product containing a plurality of particles;
Including
The nanocellulose particles are one or more nanocellulose particles selected from the group consisting of cellulose nanofiber particles and cellulose nanocrystal particles,
The toner production method, wherein the amount of the nanocellulose powder in the colorant master batch is 1% by mass or more and 10% by mass or less based on the total mass of the colorant, the resin, and the nanocellulose powder .   The method of claim 1, wherein the nanocellulose powder comprises only cellulose nanofibers.   The method according to claim 2, wherein the main component of the cellulose nanofiber particles is TEMPO oxide of bleached softwood pulp.   The nanocellulose powder WHEREIN: The width of the said cellulose nanofiber particle is 5 nm-15 nm by number average, The length of the said cellulose nanofiber particle is 600 nm-1000 nm by number average, The manufacturing method of the described toner.   In the masterbatch preparation step, the colorant masterbatch is obtained by melt-kneading a material containing the colorant, the resin, and the nanocellulose powder while lowering the temperature stepwise. 4. The method for producing a toner according to any one of the items 1 to 4. In the masterbatch preparation step, the first melt-kneading at a first temperature, the second melt-kneading at a second temperature that is 5 ° C. or more lower than the first temperature, and 5 ° C. than the second temperature. The material including the colorant, the resin, and the nanocellulose powder is melt-kneaded through the third melt-kneading at the third temperature which is the above low temperature,
The processing time of each of the first melt-kneading, the second melt-kneading and the third melt-kneading is 10 minutes or more, respectively.
The total processing time of the first melt-kneading, the second melt-kneading and the third melt-kneading is 120 minutes or less,
The method according to any one of claims 1 to 4, wherein the difference between the first temperature and the third temperature is 30 ° C or less. A toner comprising a pulverized product of a melt-kneaded product containing a colorant masterbatch,
The colorant masterbatch includes a colorant, a resin, and nanocellulose powder which is a powder of nanocellulose particles,
The nanocellulose particles are one or more nanocellulose particles selected from the group consisting of cellulose nanofiber particles and cellulose nanocrystal particles,
The toner, wherein the amount of the nanocellulose powder in the colorant master batch is 1% by mass or more and 10% by mass or less based on the total mass of the colorant, the resin, and the nanocellulose powder. It further includes an external additive which is a powder of external additive particles,
The pulverized product of the melt-kneaded product containing the colorant masterbatch constitutes a plurality of toner base particles,
A plurality of the external additive particles are attached to the surface of the toner base particles,
The toner mother particles are non-capsulated toner mother particles,
The toner according to claim 7, wherein the toner mother particles contain a polyester resin. A coloring agent, a resin, and a nanocellulose powder which is a powder of nanocellulose particles,
The nanocellulose particles are one or more nanocellulose particles selected from the group consisting of cellulose nanofiber particles and cellulose nanocrystal particles,
The colorant masterbatch, wherein the amount of the nanocellulose powder is 1% by mass or more and 10% by mass or less based on the total mass of the colorant, the resin, and the nanocellulose powder.