JP2020016689A - toner - Google Patents

Abstract

To provide a toner that is excellent in low-temperature fixability while preventing carrier contamination.SOLUTION: A toner includes toner particles. The toner particles each include a toner base particle 10 having a sea-like domain 11 that contains an amorphous polyester resin and island-like domains 12 that are distributed in an island shape with respect to the sea-like domain 11. The island-like domains 12 each contain an amorphous polyester resin and a cellulose nanofiber. The mass of the cellulose nanofiber is preferably 1 parts by mass or more and 10 parts by mass or less based on 100 parts by mass of the amorphous polyester resin.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a toner.

  Patent Document 1 discloses a toner containing toner particles containing a crystalline polyester resin.

JP 2017-125916 A

  However, it is difficult to obtain toner excellent in low-temperature fixability while suppressing carrier contamination (phenomenon in which toner components adhere to carrier particles) using only the technique disclosed in Patent Document 1. When carrier contamination occurs, the charge imparting property of the carrier (the ability to charge the toner) is reduced, and as a result, image defects such as fogging may occur.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a toner which is excellent in low-temperature fixability while suppressing carrier contamination.

  The toner according to the present invention includes toner particles. The toner particles include toner base particles having a sea-like domain containing an amorphous polyester resin and island-like domains distributed in an island-like manner with respect to the sea-like domain. The island domains include a crystalline polyester resin and cellulose nanofibers.

  According to the present invention, it is possible to provide a toner that is excellent in low-temperature fixability while suppressing carrier contamination.

FIG. 3 is a diagram illustrating an example of a cross-sectional structure of toner base particles included in the toner according to the embodiment of the present disclosure.

  Hereinafter, preferred embodiments of the present invention will be described. The toner is an aggregate (for example, powder) of toner particles. The external additive is an aggregate (for example, powder) of external additive particles. If the evaluation results (values indicating the shape, physical properties, etc.) of the powder (more specifically, the powder of the toner particles, the powder of the external additive particles, etc.) are not specified, the particles are converted from the powder. It is the number average of the values measured for each of these particles after selecting a considerable number.

The measured value of the volume median diameter (D ₅₀ ) of the powder was measured using a laser diffraction / scattering type particle size distribution analyzer (“LA-950” manufactured by Horiba, Ltd.) unless otherwise specified. Median diameter. Unless otherwise specified, the number average primary particle diameter of the powder is the circle equivalent diameter of the primary particles measured using a scanning electron microscope (Haywood diameter: the diameter of a circle having the same area as the projected area of the primary particles). Is the number average value. The number average primary particle diameter of the powder is, for example, a number average value of a circle equivalent diameter of 100 primary particles. The number average primary particle diameter of the particles refers to the number average primary particle diameter of the particles in the powder unless otherwise specified.

  Unless the strength of the charging property is specified, frictional charging is easy. For example, a standard carrier (standard carrier for negatively chargeable toner: N-01, standard carrier for positively chargeable toner: P-01) provided by the Imaging Society of Japan and a measurement target (for example, toner) are mixed and stirred. Then, the object to be measured is triboelectrically charged. Before and after the triboelectric charging, the charge amount of the object to be measured is measured with, for example, a Q / m meter (“MODEL 212HS” manufactured by Trek). A measurement object having a larger change in the charge amount before and after the triboelectric charging indicates a higher chargeability.

  Unless otherwise specified, the softening point (Tm) is a value measured using a Koka type flow tester (“CFT-500D” manufactured by Shimadzu Corporation). In the S-shaped curve (horizontal axis: temperature, vertical axis: stroke) measured by the Koka type flow tester, the temperature at which “(baseline stroke value + maximum stroke value) / 2” is equal to Tm (softening point). Equivalent to. Unless otherwise specified, the measured value of the melting point (Mp) is an endothermic curve (vertical axis: heat flow (DSC signal)) measured using a differential scanning calorimeter ("DSC-6220" manufactured by Seiko Instruments Inc.). , Horizontal axis: temperature). This endothermic peak appears due to melting of the crystallization site. The glass transition point (Tg) is a value measured according to "JIS (Japanese Industrial Standard) K7121-2012" using a differential scanning calorimeter ("DSC-6220" manufactured by Seiko Instruments Inc.) unless otherwise specified. It is. In the endothermic curve (vertical axis: heat flow (DSC signal), horizontal axis: temperature) measured by a differential scanning calorimeter, the temperature at the inflection point due to the glass transition (specifically, the extrapolation line and the fall of the baseline) The temperature at the intersection of the line with the extrapolation line) corresponds to Tg (glass transition point).

  The “principal component” of a material, unless otherwise specified, means the component that is most frequently contained in the material on a mass basis.

  The degree of hydrophobicity (or the degree of hydrophilicity) can be represented, for example, by the contact angle of a water droplet (ease of water wetting). The larger the contact angle of the water droplet, the stronger the hydrophobicity.

  Hereinafter, a compound and its derivative may be generically referred to by adding “system” after the compound name. When a polymer name is represented by adding “system” after the compound name, it means that the repeating unit of the polymer is derived from the compound or its derivative. Acrylic and methacryl may be generically referred to as "(meth) acryl".

<Toner>
The toner according to the exemplary embodiment can be suitably used, for example, as a positively chargeable toner for developing an electrostatic latent image. The toner according to the exemplary embodiment is an aggregate (for example, a powder) containing toner particles (particles each having a configuration described below). 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 (for example, a ball mill).

  The toner particles included in the toner according to the exemplary embodiment include toner mother particles having a sea-like domain containing an amorphous polyester resin and island-like domains distributed in an island-like manner with respect to the sea-like domain. The island domains include a crystalline polyester resin and cellulose nanofibers (hereinafter, sometimes referred to as CNF).

  The toner according to the exemplary embodiment, having the above-described configuration, is excellent in low-temperature fixability while suppressing carrier contamination. The reason is presumed as follows.

  In the toner according to the exemplary embodiment, the toner base particles have island domains including a crystalline polyester resin. Therefore, in the toner according to the exemplary embodiment, at the time of fixing, the crystalline polyester resin functions as a plasticizer, and the toner base particles tend to be easily softened. Therefore, the toner according to the exemplary embodiment is excellent in low-temperature fixability.

  On the other hand, since crystalline polyester resin is relatively vulnerable to mechanical stress, when toner particles containing crystalline polyester resin are used, usually, when toner particles collide with carrier particles, carrier contamination (for example, (The phenomenon that the crystalline polyester resin adheres to the carrier particles).

  However, in the toner according to the present embodiment, since CNF exists in the island domain containing the crystalline polyester resin, CNF functions as an aggregate in the island domain, and the mechanical stress of the island domain is reduced. Tends to be suppressed. Therefore, according to the toner of the exemplary embodiment, carrier contamination can be suppressed even if the island-shaped domain contains a crystalline polyester resin that is relatively vulnerable to mechanical stress. The CNF in the island domain is integrated with the printing paper at the time of fixing, and does not hinder the low-temperature fixing property.

  The toner particles included in the toner according to the exemplary embodiment may be toner particles having no shell layer, or may be toner particles having a shell layer (hereinafter, may be referred to as capsule toner particles). Is also good. In the capsule toner particles, the toner base particles include a toner core and a shell layer covering a surface of the toner core. The toner core has the above-mentioned sea-like domain and island-like domain. The shell layer contains a resin. For example, by covering a toner core that melts at a low temperature with a shell layer having excellent heat resistance, it is possible to achieve both heat-resistant storage stability and low-temperature fixability of the toner. 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 obtain a toner suitable for image formation, the volume median diameter (D ₅₀ ) of the toner base particles is preferably 4 μm or more and 9 μm or less.

  In order to further suppress carrier contamination and obtain a toner having better low-temperature fixability, the mass of CNF is preferably from 1 part by mass to 10 parts by mass with respect to 100 parts by mass of the crystalline polyester resin.

  In order to obtain a toner having better low-temperature fixability while further suppressing carrier contamination, the number average fiber length of CNF is preferably from 50 nm to 300 nm, more preferably from 55 nm to 270 nm. The method of measuring the number average fiber length of CNF is the same method as the example described later or an alternative method thereof.

  In order to obtain a toner having more excellent low-temperature fixability while further suppressing carrier contamination, the number average fiber diameter of CNF is preferably 2 nm or more and 50 nm or less, more preferably 5 nm or more and 50 nm or less. The fiber diameter of CNF is the diameter at the center in the longitudinal direction of CNF. The method of measuring the number average fiber diameter of CNF is the same method as the example described later or an alternative method thereof.

  The softening point (Tm) of the crystalline polyester resin is preferably from 60 ° C. to 120 ° C., and more preferably from 70 ° C. to 110 ° C., in order to obtain a toner having better low-temperature fixability while further suppressing carrier contamination. Is more preferable. The softening point (Tm) of the crystalline polyester resin is, for example, at least one of the type of monomer used when synthesizing the crystalline polyester resin and the molar ratio of the monomer used when synthesizing the crystalline polyester resin. It can be adjusted by changing.

  In order to obtain a toner having better low-temperature fixability while further suppressing carrier contamination, the mass of the crystalline polyester resin should be 5 parts by mass or more and 20 parts by mass or less based on 100 parts by mass of the amorphous polyester resin. Is preferred.

  In order to obtain a toner having better low-temperature fixability, the sea-like domain preferably does not contain CNF.

  In the toner according to the exemplary embodiment, the non-crystalline polyester resin constituting the sea-like domain functions as a binder resin in the toner base particles. In the toner according to the exemplary embodiment, the crystalline polyester resin and CNF in the island domains are each a kind of internal additive. In the toner according to the exemplary embodiment, the toner base particles may include, if necessary, an internal additive other than the crystalline polyester resin and CNF (more specifically, a colorant, a release agent, a charge control agent, and a magnetic powder). At least one).

  The toner particles included in the toner according to the exemplary embodiment may include an external additive. When the toner particles include an external additive, the toner particles include toner base particles and an external additive. The external additive adheres to the surface of the toner base particles. If unnecessary, the external additive may be omitted. When the external additive is omitted, the toner base particles correspond to the toner particles.

  Hereinafter, details of the toner according to the exemplary embodiment will be described with reference to the drawings as appropriate.

[Configuration of Toner Particles]
Hereinafter, an example of a configuration of toner particles (particularly, a configuration of toner base particles) included in the toner according to the exemplary embodiment will be described with reference to FIG. FIG. 1 is a diagram illustrating an example of a cross-sectional structure of toner base particles included in the toner according to the present embodiment. Note that FIG. 1 schematically illustrates each of the constituent elements for the sake of easy understanding, and the size, number, and the like of each of the illustrated constituent elements are different from the actual ones for convenience of drawing. May be different.

  As shown in FIG. 1, the toner base particles 10 include a sea-like domain 11 distributed in a sea-like manner, an island-like domain 12 (a plurality of island-like domains 12) distributed in an island-like manner with respect to the sea-like domain 11. It has a sea-island structure. The sea-like domain 11 includes a non-crystalline polyester resin. The island domains 12 include a crystalline polyester resin and one (book) or plural (books) of CNF.

  In order to obtain a toner having better low-temperature fixability while further suppressing carrier contamination, the dispersed diameter of the island domains 12 is preferably 50 nm or more and 500 nm or less.

  The dispersion diameter of the island domains 12 can be determined by photographing a cross section of the pre-stained toner particles (a cross section of the pre-stained toner mother particles 10) with an electron microscope, and obtaining the obtained photographed image using commercially available image analysis software (for example, And "WinROOF" manufactured by Mitani Shoji Co., Ltd.). If the cross section of the island-shaped domain 12 is not a perfect circle, the equivalent circle diameter (diameter of a circle having the same area as the projected area of the island-shaped domain 12) is used as the measured value of the dispersion diameter.

  The toner base particles 10 may include an island domain different from the island domain 12 (another island domain). Examples of the other island domains include, for example, an island domain containing a crystalline polyester resin and not containing CNF, and a release agent domain composed of a release agent described later. In order to further suppress carrier contamination, the content of the island domains 12 with respect to the total amount of the island domains including the crystalline polyester resin is preferably 80% by mass or more, more preferably 90% by mass or more. It is particularly preferable that the content is 100% by mass (all of the island domains including the crystalline polyester resin include CNF).

  The example of the configuration of the toner particles (particularly, the configuration of the toner base particles) included in the toner according to the exemplary embodiment has been described above with reference to FIG.

[Elements of toner particles]
Next, the components of the toner particles included in the toner according to the exemplary embodiment will be described.

(Sea-like domain: binder resin)
In the toner according to the present embodiment, the sea-like domain has a binder resin as a main component. The binder resin occupies most of the toner base particles (for example, 60% by mass or more) of all components. In order to obtain a toner having better low-temperature fixability, the content of the binder resin with respect to the total amount of the sea-like domains is preferably in the range of 70% by mass to 100% by mass, and more preferably in the range of 80% by mass to 100% by mass. Is more preferable, and the range is more preferably 90% by mass or more and 100% by mass or less.

  The binder resin, which is the main component of the sea-like domain, includes an amorphous polyester resin. The binder resin may include a resin other than the non-crystalline polyester resin. Examples of the resin other than the non-crystalline polyester resin include a thermoplastic resin other than the non-crystalline polyester resin. Examples of the thermoplastic resin other than the non-crystalline polyester resin include, for example, a styrene-based resin, an acrylate-based resin, an olefin-based resin (more specifically, a polyethylene resin and a polypropylene resin), and a vinyl resin (more specifically, Examples thereof include vinyl chloride resin, polyvinyl alcohol, vinyl ether resin, N-vinyl resin, etc.), polyamide resin, and urethane resin. Further, a copolymer of each of these resins, that is, a copolymer in which an arbitrary repeating unit is introduced into the resin (more specifically, a styrene-acrylate resin, a styrene-butadiene resin, etc.) It can be used as a binder resin.

  In order to obtain a toner having better low-temperature fixability, the content of the non-crystalline polyester resin with respect to the total amount of the binder resin is preferably in the range of 80% by mass to 100% by mass, and more preferably 90% by mass to 100% by mass. %, More preferably 95% by mass or more and 100% by mass or less.

  The non-crystalline polyester resin refers to a polyester resin in which a clear endothermic peak is not recognized in an endothermic curve measured using a differential scanning calorimeter.

  The polyester resin is obtained by polycondensing one or more polyhydric alcohols and one or more polyhydric carboxylic acids. Examples of the alcohol for synthesizing the polyester resin include the following dihydric alcohols (more specifically, aliphatic diols and bisphenols), and trihydric or higher alcohols. Examples of the carboxylic acid for synthesizing the polyester resin include a divalent carboxylic acid and a trivalent or higher carboxylic acid as shown below. In place of the polycarboxylic acid, a polycarboxylic acid derivative capable of forming an ester bond by condensation polymerization of a polycarboxylic acid anhydride, a polycarboxylic acid halide, or the like may be used.

  Preferred examples of the aliphatic diol 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, 1,12-dodecanediol, etc.) , 2-butene-1,4-diol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

  Suitable examples of bisphenol include bisphenol A, hydrogenated bisphenol A, bisphenol A ethylene oxide adduct, and bisphenol A propylene oxide adduct.

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

  Preferred examples of divalent carboxylic acids include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, adipic acid, sebacic acid, azelaic acid, malonic acid , Suberic acid, 1,10-decanedicarboxylic acid, succinic acid, alkyl succinic acid (more specifically, n-butyl succinic acid, isobutyl succinic acid, n-octyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid) And alkenyl succinic acids (more specifically, n-butenyl succinic acid, isobutenyl succinic acid, n-octenyl succinic acid, n-dodecenyl succinic acid, isododecenyl succinic acid, etc.).

  Preferred examples of the trivalent or higher carboxylic acid 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 (methylenecarboxyl) Methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, and empol trimer acid.

  Suitable polyhydric alcohols for synthesizing the non-crystalline polyester resin include bisphenol (more specifically, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, etc.). Suitable polyvalent carboxylic acids for synthesizing the non-crystalline polyester resin include aromatic dicarboxylic acids (more specifically, terephthalic acid and the like) and / or unsaturated dicarboxylic acids (more specifically, fumaric acid). Etc.).

  In the toner according to the present embodiment, only one kind of non-crystalline polyester resin may be used as the non-crystalline polyester resin contained in the sea-like domain, and a plurality of kinds of non-crystalline polyester resins (for example, having different Tg's) may be used. (A plurality of types of non-crystalline polyester resins).

(Insular domain containing crystalline polyester resin and CNF)
Island domains containing the crystalline polyester resin and CNF (hereinafter sometimes referred to as specific island domains) are distributed in an island shape with respect to the above-described sea domains. Hereinafter, the crystalline polyester resin and CNF will be described.

(Crystalline polyester resin)
Suitable polyhydric alcohols for synthesizing the crystalline polyester resin include α, ω-alkanediols having 2 to 8 carbon atoms (more specifically, ethylene glycol, 1,4-butanediol, 6-hexanediol). Suitable polyvalent carboxylic acids for synthesizing the crystalline polyester resin include α, ω-alkanedicarboxylic acids having 4 to 10 carbon atoms (including carbon atoms of two carboxy groups) (more specifically, Succinic acid, suberic acid, sebacic acid, etc.).

  In order to obtain a toner having better low-temperature fixability while improving the sharp melt property, the specific island domain preferably contains a crystalline polyester resin having a crystallinity index of 0.90 to 1.10. The crystallinity index of the crystalline polyester resin can be adjusted by changing the type or use amount (mixing ratio) of the monomer for synthesizing the crystalline polyester resin. The crystallinity index of the resin corresponds to the ratio (Tm / Mp) of the softening point (Tm: unit ° C) of the resin to the melting point (Mp: unit ° C) of the resin.

  In the toner according to the present embodiment, only one kind of crystalline polyester resin may be used as the crystalline polyester resin contained in the specific island domain, and a plurality of kinds of crystalline polyester resins (for example, plural kinds having different Tm) may be used. (A kind of crystalline polyester resin).

  The specific island domain may include a composite resin composed of a crystalline polyester resin and another resin. That is, the crystalline polyester resin in the specific island domain may be a crystalline polyester resin constituting the composite resin. As another resin constituting the composite resin, a styrene-acrylic acid-based resin is preferable. A styrene-acrylic acid-based resin is a copolymer of one or more styrene-based monomers and one or more acrylic acid-based monomers. When the specific island domain includes a composite resin composed of a crystalline polyester resin and a styrene-acrylic acid-based resin (hereinafter sometimes referred to as a specific composite resin), a toner having excellent charge stability is obtained. Can be The content of the crystalline polyester resin with respect to the total amount of the specific composite resin is, for example, 50% by mass or more and 95% by mass or less.

  Styrene-based monomers for synthesizing styrene-acrylic acid-based resins include, for example, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethyl Styrene, pt-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, and pn-dodecylstyrene.

  Examples of the acrylic monomer for synthesizing the styrene-acrylic resin include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, and (meth) acrylate. ) Isopropyl acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) ) Stearyl acrylate, lauryl (meth) acrylate, and phenyl (meth) acrylate.

[CNF]
CNF is obtained from a cellulose raw material by mechanical treatment (more specifically, pulverization treatment using a planetary ball mill) and / or chemical treatment (more specifically, heat decomposition treatment using heat-resistant cellulase). The extracted nanocellulose. The cellulose raw material is not particularly limited, and examples thereof include woody biomass obtained from plants such as wood, plants, agricultural products, and cotton.

  As a suitable method for preparing CNF, a preparation method including a pulverizing treatment step and a thermal decomposition treatment step is exemplified. Examples of the pulverizing method in the pulverizing step include a method of mechanically pulverizing woody biomass with a planetary ball mill to obtain cellulose microfibrils. As a thermal decomposition treatment method in the thermal decomposition treatment step, for example, a pulverized product (for example, microfibril) obtained in the pulverization treatment step, a buffer (for example, sodium citrate buffer), and a heat-resistant cellulase are stirred. A method in which a pulverized material (for example, microfibrils) is subjected to a thermal decomposition treatment by causing a reaction at a temperature of 70 ° C. or more and 90 ° C. or less while heating. The number-average fiber length and number-average fiber diameter of CNF can be adjusted, for example, by changing the stirring time (reaction time) in the thermal decomposition treatment step.

  The specific island domain may include components other than the above-described components. In order to obtain a toner having more excellent low-temperature fixability while further suppressing carrier contamination, the total content of the crystalline polyester resin or the composite resin (for example, the specific composite resin) and CNF must be equal to the total amount of the specific island domains. Is preferably 80% by mass or more, more preferably 90% by mass or more, and particularly preferably 100% by mass.

  In order to obtain toner excellent in low-temperature fixability while further suppressing carrier contamination, the number average fiber diameter of CNF in the specific island domain is 40 nm or more and 50 nm or less, and the crystalline polyester in the specific island domain is used. It is preferable that the softening point (Tm) of the resin is from 70 ° C to 110 ° C. Further, in order to obtain a toner having more excellent low-temperature fixability while suppressing carrier contamination, the number average fiber diameter of CNF in the specific island domain is 5 nm or more and 50 nm or less, and the crystal in the specific island domain is used. It is preferable that the softening point (Tm) of the conductive polyester resin is 75 ° C. or more and 85 ° C. or less.

(Colorant)
The toner base particles may contain a colorant. As the colorant, a known pigment or dye can be used according to the color of the toner. In order to form a high-quality image using the toner, the amount of the colorant is preferably from 1 part by weight to 20 parts by weight based on 100 parts by weight of the binder resin.

  The toner base particles may contain a black colorant. An example of a black colorant is carbon black. Further, the black colorant may be a colorant that is toned to black using a yellow colorant, a magenta colorant, and a cyan colorant.

  The toner base particles may contain a colorant. Color colorants include yellow, magenta, and 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 the yellow colorant include C.I. I. Pigment Yellow (3, 12, 13, 14, 15, 17, 62, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155) , 168, 174, 175, 176, 180, 181, 191 and 194), naphthol yellow S, Hansa yellow G, and C.I. I. Bat yellow.

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

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

(Release agent)
The toner base particles may contain a release agent. The release agent is used, for example, to obtain a toner having excellent offset resistance. In order to obtain a toner having excellent offset resistance, the amount of the release agent is preferably from 1 part by weight to 20 parts by weight based on 100 parts by weight of the binder resin.

  Examples of the release agent include ester wax, polyolefin wax (more specifically, polyethylene wax, polypropylene wax, etc.), microcrystalline wax, fluororesin wax, Fischer-Tropsch wax, paraffin wax, candelilla wax, montan wax, And caster wax. Examples of the ester wax include natural ester waxes (more specifically, carnauba wax, rice wax, and the like), and synthetic ester waxes. In the present embodiment, one type of release agent may be used alone, or a plurality of types of release agents may be used in combination.

  In order to improve the compatibility between the binder resin and the release agent, a compatibilizer may be added to the toner base particles.

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

  By including a positively chargeable charge control agent in the toner base particles, the cationicity (positive chargeability) of the toner base particles can be enhanced. Further, by adding a negatively chargeable charge control agent to the toner base particles, the anionicity (negative chargeability) of the toner base particles can be enhanced.

  Examples of positively chargeable charge control agents include pyridazine, pyrimidine, pyrazine, 1,2-oxazine, 1,3-oxazine, 1,4-oxazine, 1,2-thiazine, 1,3-thiazine, 4-thiazine, 1,2,3-triazine, 1,2,4-triazine, 1,3,5-triazine, 1,2,4-oxadiazine, 1,3,4-oxadiazine, 1,2,6- Oxadiazine, 1,3,4-thiadiazine, 1,3,5-thiadiazine, 1,2,3,4-tetrazine, 1,2,4,5-tetrazine, 1,2,3,5-tetrazine, 1, Azine compounds such as 2,4,6-oxatriazine, 1,3,4,5-oxatriazine, phthalazine, quinazoline, quinoxaline; azine fast red FC, azine fast red 12BK, azine biore Direct dyes such as BO, azine brown 3G, azine light brown GR, azine dark green BH / C, azine deep black EW, azine deep black 3RL; acid dyes such as nigrosine BK, nigrosine NB, nigrosine Z; Amine; alkylamide; quaternary ammonium salts such as benzyldecylhexylmethylammonium chloride, decyltrimethylammonium chloride, 2- (methacryloyloxy) ethyltrimethylammonium chloride, and dimethylaminopropylacrylamide methyl chloride quaternary salt; Resin. One of these charge control agents may be used alone, or two or more thereof may be used in combination.

  Examples of the negatively chargeable charge control agent include an organometallic complex which is a chelate compound. As the organometallic complex, an acetylacetone metal complex, a salicylic acid-based metal complex, and salts thereof are preferable.

  In order to obtain a toner having excellent charge stability, the content of the charge control agent is preferably 0.1 part by mass or more and 10 parts by mass or less based on 100 parts by mass of the binder resin.

(Magnetic powder)
The toner base particles may contain magnetic powder. Examples of the material of the magnetic powder include ferromagnetic metals (more specifically, iron, cobalt, nickel, etc.) and alloys thereof, and ferromagnetic metal oxides (more specifically, ferrite, magnetite, chromium dioxide, etc.) And a material that has been subjected to ferromagnetic treatment (more specifically, a carbon material to which ferromagnetism has been imparted by heat treatment, etc.). In the present embodiment, one type of magnetic powder may be used alone, or a plurality of types of magnetic powder may be used in combination.

(External additives)
The toner particles may further include an external additive. As an external addition method of the external additive, for example, the toner particles (powder) and the external additive particles (powder) are stirred together so that the external additive particles adhere to the surface of the toner base particles. Method.

  As the external additive particles, resin particles and inorganic particles are preferable. As the inorganic particles, silica particles and particles of metal oxides (more specifically, alumina, titanium oxide, magnesium oxide, zinc oxide, strontium titanate, barium titanate, etc.) are preferable. In the present embodiment, one type of external additive particles may be used alone, or a plurality of types of external additive particles may be used in combination.

  In order to sufficiently exert the function of the external additive while suppressing the detachment of the external additive particles from the toner base particles, the amount of the external additive (when a plurality of types of external additive particles are used, The total amount of the external additive particles) is preferably 0.5 parts by mass or more and 10 parts by mass or less based on 100 parts by mass of the toner base particles.

  In order to obtain a toner having excellent fluidity, it is preferable to use inorganic particles (powder) having a number average primary particle diameter of 5 nm or more and 500 nm or less as external additive particles.

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

<Production method of toner>
Next, a preferred method of manufacturing the toner according to the above-described embodiment will be described. Hereinafter, description of components overlapping with the toner according to the above-described embodiment will be omitted.

[Preparation step of CNF-dispersed resin]
First, CNF is dispersed in a crystalline polyester resin or a composite resin composed of a crystalline polyester resin and another resin (hereinafter, these may be collectively referred to as a dispersion resin). Hereinafter, an example of a method of dispersing CNF in the dispersion resin will be described.

  After a solvent (eg, tetrahydrofuran) is put in a container (eg, beaker), the dispersion resin and CNF are put into the container while stirring the contents of the container, and the contents of the container are further stirred. Conditions for stirring the mixture of the solvent, the dispersion resin, and the CNF include, for example, a rotation speed of 500 rpm or more and 2000 rpm or less, and a stirring time of 30 minutes or more and 120 minutes or less. Next, by distilling off the solvent from the contents of the container, a mixture containing a dispersing resin and CNF dispersed in the dispersing resin (hereinafter, sometimes referred to as a CNF dispersing resin) is obtained.

[Preparation Step of Toner Base Particles]
Next, toner base particles are prepared. Hereinafter, a pulverization method, which is a preferred example of a method for preparing toner base particles, will be described.

  When the toner base particles are prepared by the pulverization method, the preparation step of the toner base particles includes, for example, a melt-kneading step and a pulverizing step. The step of preparing the toner base particles may further include a mixing step before the melt-kneading step. The step of preparing the toner base particles may further include at least one of a pulverizing step and a classifying step after the pulverizing step.

  In the mixing step, the binder resin containing at least the non-crystalline polyester resin, the CNF-dispersed resin, and other internal additives added as necessary are mixed to obtain a mixture. In the melt-kneading step, the toner material is melted and kneaded to obtain a melt-kneaded product. As the toner material, for example, a mixture obtained in a mixing step is used. The dispersion diameter of the specific island domains can be adjusted by changing the melt-kneading conditions (more specifically, the shaft rotation speed and the like) in the melt-kneading step. In the pulverizing step, the obtained melt-kneaded product is cooled to, for example, room temperature (25 ° C.) and then pulverized to obtain a pulverized product. If it is necessary to reduce the diameter of the pulverized material obtained in the pulverizing step, a step of further pulverizing the pulverized substance (fine pulverizing step) may be performed. When the particle size of the pulverized material is made uniform, a step of classifying the obtained pulverized material (classification step) may be performed. Through the above steps, toner base particles as pulverized materials are obtained.

[External addition process]
Thereafter, if necessary, the toner base particles and the external additives are mixed using a mixer (for example, an FM mixer manufactured by Nippon Coke Industry Co., Ltd.), and the external additives are attached to the surfaces of the toner base particles. You may. The toner base particles may be used as the toner particles without attaching the external additive to the toner base particles. Thus, the toner (powder of toner particles) according to the above-described embodiment is obtained.

  Hereinafter, examples of the present invention will be described together with comparative examples. Note that the present invention is not limited to the scope of the embodiments.

  First, methods for measuring the softening point (Tm), glass transition point (Tg), melting point (Mp), number average fiber length, and number average fiber diameter will be described.

<Measurement of Tm>
A sample (either resin or toner base particles) was filled in a Koka flow tester (“CFT-500D” manufactured by Shimadzu Corporation). Subsequently, a sample of 1 cm ³ was melted and flown out under the conditions of a die pore diameter of 1 mm, a plunger load of 20 kg / cm ² , and a heating rate of 6 ° C./min, and an S-shaped curve of the sample (horizontal axis: temperature, vertical axis) : Stroke). The softening point of the sample was read from the obtained S-shaped curve. In the S-shaped curve, when the maximum value of the stroke is S ₁ and the stroke value of the low-temperature side baseline is S ₂ , the value of the stroke in the S-shaped curve is “(S ₁ + S ₂ ) / 2”. Temperature corresponds to the softening point (Tm) of the sample.

<Measurement of Tg and Mp>
A differential scanning calorimeter ("DSC-6220" manufactured by Seiko Instruments Inc.) was used as a measuring device. 55 mg of a sample (either resin or toner base particles) was placed in an aluminum dish (aluminum container), and the aluminum dish was set in the measuring section of the measuring device. An empty aluminum plate was used as a reference. Next, the temperature of the measurement unit was increased from −20 ° C., which is the measurement start temperature, to 170 ° C. at a rate of 10 ° C./min (first temperature increase: RUN1). Thereafter, the temperature of the measuring section was lowered from 170 ° C. to −20 ° C. at a rate of 10 ° C./min. Subsequently, the temperature of the measuring section was increased again from -20 ° C to 170 ° C at a rate of 10 ° C / min (second temperature increase: RUN2). An endothermic curve (vertical axis: heat flow (DSC signal), horizontal axis: temperature) of the sample was obtained by RUN2. From the obtained endothermic curve, Tg and Mp of the sample were read. In the endothermic curve, the temperature at the inflection point due to the glass transition (specifically, the intersection of the extrapolation line of the baseline and the extrapolation line of the falling line) corresponds to the Tg (glass transition point) of the sample, The temperature of the endothermic peak due to heat (that is, the temperature at which the amount of absorbed heat becomes maximum) corresponds to the Mp (melting point) of the sample.

<Measurement of number average fiber length and number average fiber diameter>
The powder of the object to be measured (CNF) was photographed at a magnification of 50,000 times with a field emission scanning electron microscope (“JSM-7600F” manufactured by JEOL Ltd.) to obtain 100 randomly selected CNF images. . Subsequently, the obtained image was analyzed by image analysis software (“WinROOF” manufactured by Mitani Corporation), and the fiber length and fiber diameter were measured for each of 100 CNFs. Subsequently, the sum of all measured fiber lengths and the sum of all measured fiber diameters were divided by the number of measured CNFs (100). Thereby, the number average fiber length and the number average fiber diameter of the CNF to be measured were obtained.

<Synthesis of non-crystalline polyester resin>
A method for synthesizing the non-crystalline polyester resins R-1, R-2, and R-3 used as the binder resin will be described.

[Synthesis of non-crystalline polyester resin R-1]
In a 10 L four-necked flask equipped with a thermometer (thermocouple), a dehydrating tube, a nitrogen introducing tube, and a stirrer, 370 g of bisphenol A propylene oxide adduct (average number of moles of propylene oxide added: 2 mol) was placed. , Bisphenol A ethylene oxide adduct (average number of moles of ethylene oxide added: 2 mol) of 3059 g, terephthalic acid of 1194 g, fumaric acid of 286 g, tin (II) 2-ethylhexanoate of 10 g and gallic acid of 2 g. Was. Subsequently, the contents of the flask were reacted under a nitrogen atmosphere and a temperature of 230 ° C. until the conversion reached 90% by mass. The reaction rate was calculated according to the formula: “reaction rate = 100 × actual amount of reaction product water / theoretical product water amount”. Subsequently, the contents of the flask were reacted under a reduced-pressure atmosphere (pressure 8.3 kPa) and a temperature of 230 ° C. until the Tm of the reaction product (resin) reached a predetermined temperature (89 ° C.). Resin R-1 was obtained. The amorphous polyester resin R-1 had a Tg of 50 ° C and a Tm of 89 ° C.

[Synthesis of Amorphous Polyester Resin R-2]
In a 10 L four-necked flask equipped with a thermometer (thermocouple), a dehydrating tube, a nitrogen introducing tube, and a stirrer, 1,286 g of bisphenol A propylene oxide adduct (average number of moles of propylene oxide added: 2 mol) was added. 2,218 g of bisphenol A ethylene oxide adduct (average number of moles of ethylene oxide: 2 mol), 1603 g of terephthalic acid, 10 g of tin (II) 2-ethylhexanoate, and 2 g of gallic acid. Subsequently, the contents of the flask were reacted under a nitrogen atmosphere and a temperature of 230 ° C. until the conversion represented by the above formula reached 90% by mass. Subsequently, the contents of the flask were reacted under a reduced pressure atmosphere (pressure 8.3 kPa) and a temperature of 230 ° C. until the Tm of the reaction product (resin) reached a predetermined temperature (111 ° C.). Resin R-2 was obtained. The amorphous polyester resin R-2 had a Tg of 69 ° C and a Tm of 111 ° C.

[Synthesis of Amorphous Polyester Resin R-3]
In a 10 L four-necked flask equipped with a thermometer (thermocouple), a dehydrating tube, a nitrogen introducing tube, and a stirring device, 4907 g of a bisphenol A propylene oxide adduct (average number of moles of propylene oxide added: 2 mol) was placed. , Bisphenol A ethylene oxide adduct (average number of moles of ethylene oxide added: 2 mol), 1942 g, fumaric acid 757 g, n-dodecylsuccinic anhydride 2078 g, tin 2-ethylhexanoate (II) 30 g, and gallic 2 g of acid were added. Subsequently, the contents of the flask were reacted under a nitrogen atmosphere and a temperature of 230 ° C. until the conversion represented by the above formula reached 90% by mass. Subsequently, the reaction was carried out under a reduced pressure atmosphere (pressure 8.3 kPa) and a temperature of 230 ° C. for 1 hour. Subsequently, 572 g of trimellitic anhydride is put into the flask, and the Tm of the reaction product (resin) reaches a predetermined temperature (135 ° C.) under a reduced-pressure atmosphere (pressure 8.3 kPa) and a temperature of 220 ° C. The contents of the flask were reacted to obtain a non-crystalline polyester resin R-3. The amorphous polyester resin R-3 had a Tg of 58 ° C and a Tm of 135 ° C.

<Synthesis of resin contained in island domain>
A method for synthesizing the resin contained in the island domains in the toner base particles will be described. Specifically, a method for synthesizing the crystalline polyester resins R-4 and R-5 and the composite resin R-6 of the crystalline polyester resin and the styrene-acrylic acid copolymer will be described.

[Synthesis of crystalline polyester resin R-4]
In a 10 L four-necked flask equipped with a thermometer (thermocouple), a dehydrating tube, a nitrogen introducing tube, and a stirrer, 2231 g of ethylene glycol, 3978 g of succinic acid, and 40 g of tin (II) 2-ethylhexanoate are placed. And 3 g of gallic acid. Subsequently, the contents of the flask were reacted for 4 hours in a nitrogen atmosphere and at a temperature of 180 ° C., and then the contents of the flask were reacted for 10 hours in a condition of a nitrogen atmosphere and a temperature of 210 ° C. Subsequently, the contents of the flask were reacted for 1 hour under a reduced pressure atmosphere (pressure 8.3 kPa) and a temperature of 210 ° C. to obtain a crystalline polyester resin R-4. The crystalline polyester resin R-4 had a Tm of 105 ° C., an Mp of 111 ° C., and a crystallinity index (Tm / Mp) of 0.95.

[Synthesis of crystalline polyester resin R-5]
3,744 g of 1,6-hexanediol, 5869 g of suberic acid, and tin 2-ethylhexanoate were placed in a 10-L four-necked flask equipped with a thermometer (thermocouple), a dehydrating tube, a nitrogen introducing tube, and a stirrer. (II) 40 g and 3 g of gallic acid were charged. Subsequently, the contents of the flask were reacted for 4 hours in a nitrogen atmosphere and at a temperature of 180 ° C., and then the contents of the flask were reacted for 10 hours in a condition of a nitrogen atmosphere and a temperature of 210 ° C. Subsequently, the contents of the flask were reacted for 1 hour under a reduced pressure atmosphere (pressure 8.3 kPa) and a temperature of 210 ° C. to obtain a crystalline polyester resin R-5. The crystalline polyester resin R-5 had a Tm of 80 ° C., an Mp of 84 ° C., and a crystallinity index (Tm / Mp) of 0.95.

[Synthesis of Composite Resin R-6 of Crystalline Polyester Resin and Styrene-Acrylic Acid Copolymer]
2643 g of 1,6-hexanediol, 864 g of 1,4-butanediol, and succinic acid were placed in a 10-L four-necked flask equipped with a thermometer (thermocouple), a dehydrating tube, a nitrogen introducing tube, and a stirring device. After charging 2945 g, the internal temperature of the flask was raised to 160 ° C. to dissolve the contents of the flask. Next, a mixed solution of 1831 g of styrene, 161 g of acrylic acid, and 110 g of dicumyl peroxide was dropped into the flask over 1 hour using a dropping funnel. Next, after reacting the contents of the flask for 1 hour under a nitrogen atmosphere and a temperature of 170 ° C., unreacted styrene and acrylic acid are removed for 1 hour under a reduced pressure atmosphere (pressure of 8.3 kPa) and a temperature of 200 ° C. Removed. Thereafter, the pressure in the flask was returned to atmospheric pressure, 40 g of tin (II) 2-ethylhexanoate and 3 g of gallic acid were put in the flask, and then the contents of the flask were placed in a nitrogen atmosphere and at a temperature of 210 ° C. Was reacted for 8 hours. Next, the contents of the flask were reacted for 1 hour under a reduced pressure atmosphere (pressure 8.3 kPa) and a temperature of 210 ° C., and a composite resin R-6 of a crystalline polyester resin and a styrene-acrylic acid copolymer (hereinafter, composite resin) was prepared. R-6). The composite resin R-6 had a Tm of 92 ° C, a Mp of 95 ° C, and a crystallinity index (Tm / Mp) of 0.97.

<Preparation of CNF>
[Preparation of CNF-1]
100 g of sugarcane residue (bagasse) as woody biomass and 900 g of ion-exchanged water were charged into a planetary ball mill (“P-5 classical line” manufactured by Fritsch), and the sugarcane residue was mechanically pulverized at a rotation speed of 400 rpm. . The obtained pulverized material was filtered (solid-liquid separation) to remove water, and then dried to obtain microfibrils.

  Next, in a flask equipped with a thermometer (thermocouple) and a stirrer, 10 g of the microfibrils obtained by the above procedure, 990 g of a sodium citrate buffer solution having a pH of 5.0, and a heat-resistant cellulase (Wako Pure Chemical Industries, Ltd.) 1 mL of "Cellulase, Thermostable, Recombinant, Solution" manufactured by the company. Next, the contents of the flask were stirred for 24 hours at a temperature of 80 ° C. and a rotation speed of 100 rpm, and the precipitate in the flask was filtered off. Next, the obtained precipitate was washed with water and dried to obtain a powder of CNF-1 as CNF derived from a sugarcane residue. CNF-1 had a number average fiber length of 262 nm and a number average fiber diameter of 44 nm.

[Preparation of CNF-2]
A CNF-2 powder was obtained in the same manner as in the preparation of CNF-1, except that the stirring time for stirring the contents of the flask at a temperature of 80 ° C. and a rotation speed of 100 rpm was changed to 30 hours. CNF-2 had a number average fiber length of 155 nm and a number average fiber diameter of 18 nm.

[Preparation of CNF-3]
A CNF-3 powder was obtained in the same manner as in the preparation of CNF-1, except that the stirring time when stirring the contents of the flask at a temperature of 80 ° C. and a rotation speed of 100 rpm was changed to 36 hours. CNF-3 had a number average fiber length of 58 nm and a number average fiber diameter of 8 nm.

<Preparation of Toner TA-1>
[Preparation step of CNF-dispersed resin]
After putting 889 g of tetrahydrofuran into the beaker, 100 g of the composite resin R-6 was put into the beaker while stirring the contents of the beaker at 1000 rpm using a stirrer and a stirrer chip. Further, after 5 g of CNF-2 was put into the beaker, the contents of the beaker were stirred at a rotation speed of 1000 rpm for 1 hour. Next, tetrahydrofuran was distilled off from the contents of the beaker to obtain a CNF-dispersed resin containing the composite resin R-6 and the CNF dispersed in the composite resin R-6.

[Preparation Step of Toner Base Particles]
Using an FM mixer (“FM-20B” manufactured by Nippon Coke Industry Co., Ltd.), at a rotation speed of 2400 rpm, 100 g of CNF-dispersed resin (CNF-dispersed resin obtained by the above-described procedure) and 300 g of non-crystalline Polyester resin R-1, 100 g of non-crystalline polyester resin R-2, 600 g of non-crystalline polyester resin R-3, and 40 g of a charge control agent ("BONTRON (registered trademark) P" manufactured by Orient Chemical Co., Ltd.) -51 ", component: quaternary ammonium salt), 60 g of a release agent (" Nissan Elektor (registered trademark) WEP-3 "manufactured by NOF Corp., component: ester wax), and 144 g of a colorant (Sanyo And "Colortex (registered trademark) Blue B1021" (a component: phthalocyanine blue) manufactured by Dye Co., Ltd. for 3 minutes. Subsequently, the obtained mixture was melt-kneaded using a twin-screw extruder (“PCM-30” manufactured by Ikegai Co., Ltd.) under the conditions of a material supply speed of 5 kg / hour, a shaft rotation speed of 160 rpm, and a cylinder temperature of 100 ° C. . Thereafter, the obtained melt-kneaded product was cooled. Subsequently, the cooled melt-kneaded material was roughly pulverized using a pulverizer (“Rotoplex (registered trademark)” manufactured by Hosokawa Micron Corporation). Subsequently, the obtained coarsely pulverized product was finely pulverized using a jet mill ("Ultrasonic Jet Mill I" manufactured by Nippon Pneumatic Industries, Ltd.). Subsequently, the obtained finely pulverized material was classified using a classifier (a classifier utilizing the Coanda effect: “Elbow Jet EJ-LABO type” manufactured by Nippon Steel Mining Co., Ltd.), and the median volume diameter (D ₅₀₎ ) 6.7 μm toner base particles were obtained. The obtained toner base particles had a Tg of 49 ° C. and a Tm of 90 ° C.

[External addition process]
Using an FM mixer (“FM-10B” manufactured by Nippon Coke Industry Co., Ltd.), 100 parts by mass of the toner base particles obtained by the above-described procedure and a hydrophobic silica particle under the conditions of a rotation speed of 3000 rpm and a jacket temperature of 20 ° C. (“AEROSIL (registered trademark) R972” manufactured by Nippon Aerosil Co., Ltd., number average primary particle diameter: 16 nm) 1.5 parts by mass, and conductive titanium oxide particles (“EC-100” manufactured by Titanium Industry Co., Ltd.) 1.0 Parts by weight were mixed for 10 minutes. As a result, external additives (hydrophobic silica particles and conductive titanium oxide particles) were attached to the surfaces of the toner base particles. In addition, about the hydrophobic silica particle, what was disintegrated using the jet mill ("Ultrasonic jet mill I type" made by Nippon Pneumatic Industries, Ltd.) was used. Subsequently, the obtained powder was sieved using a 200-mesh (mesh opening: 75 μm) sieve. As a result, a positively charged toner TA-1 (powder of toner particles) was obtained.

  The cross section of the toner particles contained in the obtained toner TA-1 was observed by the following method, and the details of the sea-like domain and the island-like domain were confirmed. In toner TA-1, the sea-like domain contained an amorphous polyester resin and did not contain CNF. Further, in the toner TA-1, the toner mother particles had an island-like domain containing a crystalline polyester resin and CNF. In the toner TA-1, all of the island domains including the crystalline polyester resin contained CNF.

[Method for Observing Section of Toner Particle]
After dispersing the toner TA-1 in a visible light curable resin ("Aronix (registered trademark) D-800" manufactured by Toagosei Co., Ltd.), the resin was cured by irradiation with visible light to obtain a cured product. Thereafter, a knife for making ultra-thin sections (“Sumi Knife (registered trademark)” manufactured by Sumitomo Electric Industries, Ltd .: a diamond knife with a blade width of 2 mm and a blade angle of 45 °) and an ultramicrotome (“EM UC6” manufactured by Leica Microsystems, Inc.) Was used to cut a cured product at a cutting speed of 0.3 mm / sec to produce a 150 nm thick flake. The obtained flakes were exposed to a vapor of an aqueous ruthenium tetroxide solution for 10 minutes on a copper mesh to carry out Ru staining. Subsequently, the cross section of the toner particles in the stained slice sample was photographed using a transmission electron microscope (TEM) (“H-7100FA” manufactured by Hitachi High-Technologies Corporation). In addition, among CNF, the non-crystalline polyester resin, and the crystalline polyester resin, CNF was most easily dyed by Ru. The non-crystalline polyester resin was more easily dyed by Ru than the crystalline polyester resin.

<Preparation of Toners TA-2 to TA-7>
In the preparation process of the CNF-dispersed resin, the toners TA-2 to TA- were prepared in the same manner as in the production of the toner TA-1, except that the type and amount of CNF used and the type of the resin were as shown in Table 1. 7 were produced. Each of the toners TA-2 to TA-7 was a positively chargeable toner. Further, for the toners TA-2 to TA-7, the cross section of each toner particle is observed by the same method as the above-described method for observing the cross section of the toner particles contained in the toner TA-1, and details of the sea-like domain and the island-like domain are obtained. It was confirmed. In all of the toners TA-2 to TA-7, the sea-like domain contained an amorphous polyester resin and did not contain CNF. Further, in each of the toners TA-2 to TA-7, the toner mother particles had an island domain including a crystalline polyester resin and CNF. In each of the toners TA-2 to TA-7, all of the island domains including the crystalline polyester resin contained CNF.

<Preparation of Toner TB-1>
In the preparation process of the toner base particles, positive charging was performed in the same manner as in the preparation of the toner TA-1, except that 95 g of the composite resin R-6 and 5 g of CNF-2 were used instead of 100 g of the CNF-dispersed resin. Toner TB-1 was produced. Further, with respect to the toner TB-1, the cross section of the toner particles was observed by the same method as the above-described method of observing the cross section of the toner particles contained in the toner TA-1, and the details of the sea-like domain and the island-like domain were confirmed. In Toner TB-1, the sea-like domain contained an amorphous polyester resin and CNF. Further, in the toner TB-1, the toner mother particles had the island domains including the crystalline polyester resin. However, in the toner TB-1, the toner mother particles did not have the island domains including the crystalline polyester resin and CNF.

<Preparation of Toner TB-2>
Except for using 100 g of the composite resin R-6 instead of 100 g of the CNF-dispersed resin in the preparation process of the toner base particles, a positively-charged toner TB-2 was produced in the same manner as in the production of the toner TA-1. Was prepared. Further, with respect to the toner TB-2, the cross section of the toner particles was observed by the same method as the above-described cross-sectional observation method of the toner particles contained in the toner TA-1, and the details of the sea-like domain and the island-like domain were confirmed. In Toner TB-2, the sea-like domain contained an amorphous polyester resin. Further, in the toner TB-2, the toner base particles had island domains including the crystalline polyester resin. However, in the toner TB-2, the toner mother particles did not have the island domains including the crystalline polyester resin and CNF.

<Preparation of Toner TB-3>
In the process of preparing the toner base particles, a positively chargeable toner TB-3 was prepared in the same manner as in the preparation of the toner TA-1, except that 5 g of CNF-2 was used instead of 100 g of CNF dispersed resin. did. Further, for the toner TB-3, the cross section of the toner particles was observed by the same method as the above-described method of observing the cross section of the toner particles contained in the toner TA-1. In the toner TB-3, the toner mother particles did not contain the crystalline polyester resin. In the toner TB-3, CNF was dispersed throughout the toner base particles.

<Evaluation method>
[Preparation of two-component developer]
Kyocera Document Solutions Co., Ltd. carrier for “TASKlfa8052ci” (Powder Tech Co., Ltd., median volume diameter (D ₅₀ ): 35 μm, volume resistivity: 1.0 × 10 ⁷ Ω · cm, 3000 (10 ³ / 4π · A / m) and 100 parts by mass of a saturation magnetization under an applied magnetic field of 70 A · m ² / kg) and 8 parts by mass of a toner used for evaluation were manufactured by a shaker mixer (Willie & Bakkofen (WAB)). The mixture was mixed for 30 minutes using a “Tabler (registered trademark) mixer T2F” to prepare a two-component developer used for evaluation.

[Low-temperature fixability]
As the evaluation device, a multifunction device (an evaluation device in which the fixing temperature can be changed by modifying “TASKlfa8052ci” manufactured by Kyocera Document Solutions Inc.) was used. The two-component developer prepared as described above was charged into the cyan developing device of the evaluation machine, and the replenishing toner (toner to be evaluated) was charged into the cyan toner container of the evaluation machine.

Under the environment of a temperature of 23 ° C. and a humidity of 50% RH, the amount of toner applied to the evaluation paper (“ColorCopy (registered trademark)” manufactured by Mondi, A4 size, 90 g / m ² ) was evaluated using the above-described evaluation machine. Under a condition of 0 mg / cm ² , a solid image (specifically, an unfixed toner image) having a size of 25 mm × 25 mm was formed. Subsequently, the evaluation sheet on which the image was formed was passed through a fixing device of the evaluation machine. At this time, it was determined whether fixing was possible at each fixing temperature while increasing the fixing temperature of the fixing device by 2 ° C. from 100 ° C., and the minimum temperature (minimum fixing temperature) at which the solid image (toner image) could be fixed on the evaluation paper was measured. . Whether or not the toner could be fixed was confirmed by a rubbing test as described below. Specifically, the evaluation sheet passed through the fixing device is folded in half so that the surface on which the image is formed is on the inside and the center of the image is a fold, and the fold is made using a 1 kg brass weight covered with cloth. It rubbed five times on the top. Subsequently, the evaluation paper was spread, and a bent portion (a part where a solid image was formed) of the evaluation paper was observed. Then, the length (peeling length) of the peeled toner at the bent portion was measured. The lowest fixing temperature among the fixing temperatures at which the peeling length was 1 mm or less was defined as the lowest fixing temperature. When the minimum fixing temperature was 140 ° C. or lower, it was evaluated as “excellent in low-temperature fixing property”, and when the minimum fixing temperature was higher than 140 ° C., it was evaluated as “not excellent in low-temperature fixing property”.

[Heat storage stability]
2 g of toner (toner used for evaluation) was put in a polyethylene container (capacity: 20 mL), and the polyethylene container was sealed. Next, the sealed container was allowed to stand in a thermostat set at 58 ° C. for 3 hours. Thereafter, the toner removed from the container was cooled to room temperature (25 ° C.) to obtain an evaluation object.

The obtained evaluation object was placed on a 100-mesh (mesh size: 150 μm) sieve having a known mass. Then, the mass of the sieve including the evaluation target was measured, and the mass of the toner before sieving was obtained. Subsequently, the sieve was set in a powder property evaluation device (“Powder Tester (registered trademark) PT-X” manufactured by Hosokawa Micron Corporation), and according to the manual of the powder property evaluation device, for 30 seconds under the condition of an amplitude of 1.0 mm, The sieve was vibrated, and the evaluation object was sieved. After sieving, the mass of the toner that did not pass through the sieve was measured. Then, based on the mass of the toner before the sieving and the mass of the toner after the sieving, the degree of aggregation (unit: mass%) was determined according to the following equation. When the degree of aggregation was 10% by mass or less, it was evaluated as having excellent heat-resistant storage stability. On the other hand, when the agglomeration degree exceeded 10% by mass, it was evaluated that the heat storage stability was not excellent. The “mass of the toner after sieving” in the following formula is the mass of the toner not passing through the sieve, and the mass of the toner remaining on the sieve after the sieving.
Aggregation degree = 100 × mass of toner after sieving / mass of toner before sieving

[Carrier contamination]
A multifunction machine ("TASKlfa8052ci" manufactured by Kyocera Document Solutions Inc.) was used as an evaluation machine. The two-component developer prepared by the above-mentioned method was charged into a cyan developing device of an evaluation machine. Then, under the environment of a temperature of 23 ° C. and a humidity of 50% RH, the cyan developing device of the evaluation machine was driven by continuously outputting a blank image on printing paper (A4 size) for 30 minutes using the above evaluation machine. . Next, after taking out the two-component developer from the developing device for cyan of the evaluator, the carrier was separated from the two-component developer using a 795-mesh (16 μm opening) sieve to obtain a carrier for evaluating contamination. . GC / MS analysis was performed on the obtained carrier for evaluating contamination, and a GC / MS mass spectrum was obtained. Then, the amount of the polyester resin transferred from the toner to the carrier during the operation of the cyan developing device and adhered to the carrier (the transfer amount of the polyester resin to the carrier) was determined. And conditions of GC / MS analysis, carrier migration weight of the polyester resin (hereinafter, the amount of carrier migration, or wherein the carrier migration amount Y _T.) The Determination of were as follows.

(Conditions for GC / MS analysis)
As the measuring device, a gas chromatograph mass spectrometer ("GCMS-QP2010 Ultra" manufactured by Shimadzu Corporation) and a multi-shot pyrolyzer ("PY-3030D" manufactured by Frontier Lab Co., Ltd.) were used. As a column, a GC column (“Agilent (registered trademark) J & W Ultra Inert Capillary GC Column DB-5ms” manufactured by Agilent Technologies), a phase: an allylene phase in which arylene is added to a siloxane polymer to strengthen the main chain of the polymer, (Inner diameter: 0.25 mm, film thickness: 0.25 μm, length: 30 m). GC / MS analysis was performed on 100 μg of the measurement target (contamination evaluation carrier) under the following analysis conditions, and a mass spectrum including a peak derived from the polyester resin (horizontal axis: mass of ions / charge number of ions, vertical axis: Detection intensity).
・ Thermal decomposition temperature: heating furnace “600 ° C”, interface section “320 ° C”
Temperature rising condition: The temperature was raised from 40 ° C. to 320 ° C. at a rate of 28 ° C./min, and kept at 320 ° C. for 5 minutes.
・ Carrier gas: Helium (He) gas (linear velocity: 36.1 cm / min)
-Column head pressure: 49.7 kPa
-Injection mode: split injection (split ratio 1: 200)
・ Carrier flow rate: Total flow rate “204 mL / min”, column flow rate “1 mL / min”, purge flow rate “3 mL / min”

(How to calculate career transfer amount)
Based on the mass spectrum (GC / MS mass spectrum) obtained for the contamination evaluation carrier by the GC / MS analysis, the amount of the polyester resin adhered to the contamination evaluation carrier (carrier transfer amount) was determined. Specifically, using a calibration curve prepared in advance (a calibration curve indicating the relationship between the peak area of the GC / MS mass spectrum and the amount of polyester resin adhered), the evaluation of contamination was performed based on the measured peak area derived from the polyester resin. the amount Y _a (unit: g) of the polyester resin adhering to use carrier was determined. Then, the amount Y _B (unit: g) of contaminating evaluation carrier used for the measurement and, from the amount Y _A of the obtained polyester resin, the carrier proceeds according to the equation _{"Y T = 100 × Y A /} Y B " The amount Y _T (unit: mass%) was calculated. When the carrier transfer amount Y _T was 5% by mass or less, it was evaluated that “carrier contamination could be suppressed”, and when it exceeded 5% by mass, “carrier contamination could not be suppressed”.

For each of the toner TA-1~TA-7 and TB-1~TB-3, indicating the lowest fixing temperature, degree of aggregation, and the carrier migration amount Y _T in Table 2.

  In the toners TA-1 to TA-7, the toner particles were provided with toner mother particles having a sea-like domain containing an amorphous polyester resin and island-like domains distributed in an island-like manner with respect to the sea-like domain. . In the toners TA-1 to TA-7, the toner mother particles had island domains containing the crystalline polyester resin and CNF. In the toners TA-1 to TA-7, the dispersion diameter of the island domains including the crystalline polyester resin and CNF was 50 nm or more and 500 nm or less.

As shown in Table 2, the minimum fixing temperature of the toners TA-1 to TA-7 was 140 ° C. or lower. Therefore, the toners TA-1 to TA-7 were excellent in low-temperature fixability. In the toner TA-1~TA-7, carrier migration amount Y _T is equal to or less than 5 wt%. Therefore, the toners TA-1 to TA-7 were able to suppress carrier contamination.

  In the toners TB-1 and TB-2, the toner mother particles did not have the island domains including the crystalline polyester resin and CNF. In the toner TB-3, the toner mother particles did not contain the crystalline polyester resin.

As shown in Table 2, the minimum fixing temperatures of the toners TB-1 and TB-3 exceeded 140 ° C. Therefore, the toners TB-1 and TB-3 were not excellent in low-temperature fixability. In the toners TB-1 and TB-2, the carrier transfer amount Y _T exceeded 5% by mass. Therefore, the toners TB-1 and TB-2 could not suppress carrier contamination.

  The above results show that the present invention can provide a toner excellent in low-temperature fixability while suppressing carrier contamination.

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

Reference Signs List 10 toner base particles 11 sea-like domain 12 island-like domain

Claims (6)

A toner comprising toner particles,
The toner particles are provided with toner base particles having a sea-like domain containing an amorphous polyester resin, and island-like domains distributed in an island-like manner with respect to the sea-like domain.
The toner, wherein the island domains include a crystalline polyester resin and cellulose nanofibers.   The toner according to claim 1, wherein the mass of the cellulose nanofiber is 1 part by mass or more and 10 parts by mass or less based on 100 parts by mass of the crystalline polyester resin.   The toner according to claim 1, wherein the number average fiber length of the cellulose nanofibers is 50 nm or more and 300 nm or less.   The toner according to any one of claims 1 to 3, wherein the number average fiber diameter of the cellulose nanofiber is 2 nm or more and 50 nm or less.   The toner according to any one of claims 1 to 4, wherein the mass of the crystalline polyester resin is 5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the non-crystalline polyester resin.   The toner according to claim 1, wherein the sea-like domain does not include cellulose nanofiber.

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