JP6610125B2 - Bright toner, electrostatic charge image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method - Google Patents

Description

  The present invention relates to a glitter toner, an electrostatic charge image developer, a toner cartridge, a process cartridge, an image forming apparatus, and an image forming method.

  In recent years, the use of glitter toner containing a glitter pigment has been studied for the purpose of forming an image having a brightness such as metallic luster.

  Examples of such glittering toner include, for example, Patent Document 1, “Electrophotographic toner containing at least a binder resin, a colorant and a release agent, wherein the colorant is a metallic pigment, In the viscoelasticity of the toner, the loss loss modulus (G ″) / storage elastic modulus (G ′) = tangent loss represented by tangent loss (tan δ) has a peak at 80 to 160 [° C.], and the tangent loss. An electrophotographic developing toner having a peak value of 3 or more is disclosed.

  Patent Document 2 states that “a binder resin having an acid value of less than 10 mgKOH / g and / or a precursor thereof (H), which is soluble in an organic solvent at the liquid temperature during the emulsification dispersion process, is hardly soluble in the organic solvent. In a water-based medium in which resin fine particles are dispersed in a toner composition solution dissolved or dispersed in the organic solvent containing at least a polyester-based polymer (L) having an acid value of 20 mgKOH / g to 50 mgKOH / g and a metallic metallic pigment A toner having base particles formed by at least emulsifying or dispersing and converging, wherein the base particles have an acid value of 20 mgKOH / g or less and 50 mgKOH / g or less which is hardly soluble in an organic solvent containing a metal pigment. The domain of the polyester polymer (L) is dispersed in a matrix of the binder resin (H) having an acid value of less than 10 mgKOH / g and soluble in an organic solvent. It discloses electrophotographic toner ", characterized in that.

JP2012-208142A JP 2013-057906 A

An object of the present invention is to provide a glossy toner having toner particles including a binder resin, a flat glossy pigment, and a release agent, on the surface of the toner particles measured by an X-ray photoelectron spectrometer (XPS). The present invention provides a glitter toner that suppresses the occurrence of dullness in a glitter image as compared with the case where the C1S spectrum intensity of the release agent exposed on the surface of the toner particles with respect to the C1S spectrum intensity exceeds 3.0 %. .

  The above problem is solved by the following means.

The invention according to <1>
Having toner particles including a binder resin, a flat glitter pigment and a release agent;
The C1S spectral intensity of the release agent exposed on the surface of the toner particles relative to the C1S spectral intensity of the surface of the toner particles measured by an X-ray photoelectron spectrometer (XPS) is 0 % or more and 3.0 % or less. Bright toner.

The invention according to < 2 >
The glitter toner according to < 1 > , wherein the toner particles include a urea-modified polyester resin as the binder resin.

The invention according to < 3 >
< 1 > or < 2 > The electrostatic charge image developer containing the brilliant toner as described in < 2 > .

The invention according to < 4 >
Containing the glitter toner according to < 1 > or < 2 > ;
A toner cartridge to be attached to and detached from the image forming apparatus.

The invention according to < 5 >
< 3 > , the developer for developing an electrostatic image formed on the surface of the image holding member as a toner image with the electrostatic image developer, the developer comprising the electrostatic image developer according to < 3 > ,
A process cartridge attached to and detached from the image forming apparatus.

The invention according to < 6 >
An image carrier,
Charging means for charging the surface of the image carrier;
An electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image carrier;
Developing means for containing the electrostatic charge image developer according to < 3 > and developing the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer;
Transfer means for transferring a toner image formed on the surface of the image carrier to the surface of a recording medium;
Fixing means for fixing the toner image transferred to the surface of the recording medium;
An image forming apparatus comprising:

The invention according to < 7 >
A charging step for charging the surface of the image carrier;
An electrostatic charge image forming step of forming an electrostatic charge image on the surface of the charged image carrier;
A developing step of developing, as a toner image, an electrostatic charge image formed on the surface of the image carrier with the electrostatic charge image developer according to < 3 > ;
A transfer step of transferring a toner image formed on the surface of the image carrier to the surface of a recording medium;
A fixing step of fixing a toner image transferred onto the surface of the recording medium at a contact portion between a fixing member and a pressure member disposed in contact with the fixing member;
An image forming method comprising:

According to the invention according to < 1 > , in the glitter toner having toner particles including the binder resin, the flat glitter pigment, and the release agent, the exposure rate of the release agent on the surface of the toner particles is 3. A glittering toner that suppresses the occurrence of dullness in a glittering image is provided as compared with the case of exceeding 0 atom%.
According to the invention according to < 2 > , a glittering toner that suppresses the occurrence of dullness in a glittering image is provided as compared with the case where the toner particles contain only unmodified polyester resin as a binder resin.

According to the invention according to < 3 > , < 4 > , < 5 > , < 6 > , or < 7 > , the glitter having toner particles including a binder resin, a flat glitter pigment, and a release agent. In the toner, an electrostatic charge image developer, a toner cartridge, and the like that suppress the occurrence of dullness of the glitter image compared to the case where the glitter toner having the exposure rate of the release agent on the surface of the toner particles exceeding 3.0 atom% is applied. A process cartridge, an image forming apparatus, or an image forming method is provided.

FIG. 3 is a cross-sectional view schematically illustrating an example of toner particles according to the exemplary embodiment. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an exemplary embodiment. It is a schematic block diagram which shows an example of the process cartridge which concerns on this embodiment.

  Hereinafter, an embodiment which is an example of the present invention will be described in detail.

<Brightness toner>
The glitter toner according to the present embodiment (hereinafter sometimes referred to as “toner”) has toner particles including a binder resin, a flat glitter pigment, and a release agent. Then, the C1S spectral intensity of the release agent exposed on the surface of the toner particles relative to the C1S spectral intensity of the surface of the toner particles measured by an X-ray photoelectron spectrometer (XPS) (hereinafter, “ exposure rate of the release agent ”). ")" Is 0 % or more and 3.0 % or less. Hereinafter, the unit of the exposure rate of the release agent is indicated as “atom%” for convenience.

  The toner according to the present embodiment suppresses the occurrence of dullness in the glitter image due to the above configuration. The reason is presumed as follows.

  First, glitter is imparted to a fixed image with glitter toner having toner particles containing a flat glitter pigment and a binder resin. The glitter toner has a property that heat is easily transmitted to the toner particles when the toner image is fixed because the glitter pigment has high thermal conductivity. For this reason, when a release agent is included in the toner particles, the release agent easily melts at the time of fixing the toner image, and excessive bleeding may occur from the toner particles. The release agent exuded excessively is interposed between the toner image and the fixing means (a fixing member in contact with the toner image), and easily adheres to the surface of the fixing member. As the image is repeatedly formed, the release agent that exudes excessively is laminated on the surface of the fixing member. An image fixed on the surface of the fixing member where the release agent that has exuded excessively is laminated has a larger amount of release agent adhering to the image surface than an image fixed on the surface of the other fixing member. , It may be visually recognized as "dullness".

  Therefore, the exposure rate of the release agent on the surface of the toner particles is set to 0 atom% or more and 3.0 atom% or less so that the release agent is included in the toner particles, and the release agent exposed on the surface of the toner particles is eliminated or reduced. To do. This suppresses the release agent from exuding excessively from the toner particles when the toner image is fixed. For this reason, the amount of the release agent attached to the surface of the fixing member is reduced, and even if the image is repeatedly formed, the lamination of the release agent on the surface of the fixing member is suppressed.

From the above, it is presumed that the toner according to the present embodiment suppresses the occurrence of dullness in the glitter image by the above configuration.
In particular, when an image having a high image density (for example, 80% or more) is formed, the amount of the release agent adhering to the surface of the fixing member is increased, and the image tends to be dull. Then, the occurrence of dullness in the image is suppressed.

In the toner according to the exemplary embodiment, the exposure rate of the release agent (the exposure rate of the release agent on the surface of the toner particles) is 0 atom% or more and 3.0 atom% or less, but suppresses the occurrence of dullness in the glitter image. From this point, it is 0 atom% or more and 2.0 atom% or less, and 0 atom% (that is, the release agent is not exposed) is more preferable.
Methods for controlling the exposure rate of the release agent within the above range include, for example, a method of reducing the amount of the release agent, a method of selecting the type of the release agent (for example, in the production of toner particles by a wet method, A method using a low release agent), a method in which the toner particles have a core / shell structure, and the release agent is included only in the core (core portion).

  Here, the exposure rate of the release agent is a value obtained by XPS (X-ray photoelectron spectroscopy) measurement. As an XPS measuring apparatus, JPS-9000MX manufactured by JEOL Ltd. is used. For measurement, MgKα ray is used as an X-ray source, acceleration voltage is 10 kV, and emission current is 30 mA. Here, the amount of the release agent on the toner surface is quantified by the peak separation method of the C1S spectrum. In the peak separation method, the measured C1S spectrum is separated into each component using curve fitting by the least square method. As a component spectrum that is a base for separation, a C1S spectrum obtained by independently measuring the release agent and the binder resin used for the production of the toner particles is used.

In the toner according to the exemplary embodiment, “brightness” indicates that the image formed with the bright toner has a brightness such as a metallic luster when visually recognized.
Specifically, when a solid image is formed, the toner according to the exemplary embodiment has a light receiving angle of + 30 ° measured when incident light having an incident angle of −45 ° is irradiated to the image by a goniophotometer. It is preferable that the ratio (X / Y) of the reflectance X at the light receiving angle and the reflectance Y at the light receiving angle of −30 ° is 2 or more and 100 or less.

A ratio (X / Y) of 2 or more indicates that there is more reflection on the side opposite to the incident side (angle + side) than on the side on which incident light enters (angle-side). That is, the irregular reflection of the incident light is suppressed. When irregular reflection occurs in which incident light is reflected in various directions, the color looks dull when the reflected light is visually confirmed. Therefore, when the ratio (X / Y) is less than 2, gloss may not be confirmed even when the reflected light is viewed, and the glitter may be inferior.
On the other hand, if the ratio (X / Y) exceeds 100, the viewing angle at which the reflected light can be visually recognized becomes too narrow, and the specularly reflected light component is large, so that it may appear black depending on the viewing angle. Further, a toner having a ratio (X / Y) exceeding 100 is difficult to manufacture.

  The ratio (X / Y) is more preferably 4 or more and 50 or less, further preferably 6 or more and 20 or less, and more preferably 8 or more and 15 or less from the viewpoint of glitter and toner productivity. It is particularly preferred.

-Measurement of ratio (X / Y) with goniophotometer-
Here, the incident angle and the light receiving angle will be described first. In this embodiment, when measuring with a goniophotometer, the incident angle is set to −45 ° because the measurement sensitivity is high for an image in a wide range of glossiness.
The reason why the light receiving angles are set to −30 ° and + 30 ° is that the measurement sensitivity is highest in evaluating an image having a glitter feeling and an image having no glitter feeling.

Next, a method for measuring the ratio (X / Y) will be described.
Incident light with an incident angle of −45 ° is incident on the image (glossy image) to be measured using a spectroscopic variable angle color difference meter GC5000L manufactured by Nippon Denshoku Industries Co., Ltd. as a variable angle photometer. Then, the reflectance X at the light receiving angle + 30 ° and the reflectance Y at the light receiving angle −30 ° are measured. Note that the reflectance X and the reflectance Y were measured at intervals of 20 nm for light having a wavelength in the range of 400 nm to 700 nm, and the average value of the reflectance at each wavelength was obtained. The ratio (X / Y) is calculated from these measurement results.

The toner according to the exemplary embodiment preferably satisfies the following requirements (1) to (2) from the viewpoint of satisfying the ratio (X / Y).
(1) The average equivalent circle diameter D is longer than the average maximum thickness C of the toner particles.
(2) When the cross section in the thickness direction of the toner particles is observed, the brightness in which the angle between the long axis direction of the toner particles and the long axis direction of the glitter pigment is in the range of −30 ° to + 30 °. The proportion of the luminescent pigment is 60% or more of the total bright pigment observed.

If the toner particles have a flat shape with a circle-equivalent diameter longer than the thickness (see FIG. 1), the flat surface of the toner particles is flat on the surface of the recording medium due to pressure during fixing in the image forming fixing process. It is thought that they are lined up to face each other. In FIG. 1, 2 denotes toner particles, 4 denotes a bright pigment, and L denotes the thickness of the toner particles.
Therefore, among the flat (scale-like) bright pigments contained in the toner particles, “the angle between the major axis direction in the cross section of the toner and the major axis direction of the bright pigment is shown in (2) above”. It is considered that the glitter pigments satisfying the requirement “in the range of −30 ° to + 30 °” are arranged so that the surface side having the maximum area faces the recording medium surface. When the image formed in this way is irradiated with light, the ratio of the glitter pigment that diffusely reflects the incident light is suppressed, so that the range of the ratio (X / Y) described above is achieved. It is done.

  Hereinafter, details of the toner according to the exemplary embodiment will be described.

  The toner according to this embodiment has toner particles. The toner may have an external additive externally added to the toner particles as necessary.

(Toner particles)
The toner particles include a binder resin, a flat glitter pigment, and a release agent. The toner particles may contain other additives as required.

-Binder resin-
Examples of the binder resin include styrenes (eg, styrene, parachlorostyrene, α-methylstyrene, etc.), (meth) acrylic acid esters (eg, methyl acrylate, ethyl acrylate, n-propyl acrylate, acrylic acid). n-butyl, lauryl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, etc.), ethylenically unsaturated nitriles (for example, acrylonitrile, Methacrylonitrile, etc.), vinyl ethers (eg, vinyl methyl ether, vinyl isobutyl ether, etc.), vinyl ketones (vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl ketone, etc.), olefins (eg, ethylene, propylene, etc.) Emissions, a homopolymer of a monomer such as butadiene) and the like, or a vinyl-based resin composed of these monomers with two or more combinations copolymer.
As the binder resin, for example, epoxy resin, polyester resin, polyurethane resin, polyamide resin, cellulose resin, polyether resin, non-vinyl resin such as modified rosin, a mixture of these with the vinyl resin, or these Examples also include a graft polymer obtained by polymerizing a vinyl monomer in the coexistence.
These binder resins may be used alone or in combination of two or more.

A polyester resin is suitable as the binder resin.
Examples of the polyester resin include known polyester resins.

  As a polyester resin, the condensation polymer of polyhydric carboxylic acid and polyhydric alcohol is mentioned, for example. In addition, as a polyester resin, a commercial item may be used and what was synthesize | combined may be used.

Examples of the polyvalent carboxylic acid include aliphatic dicarboxylic acids (eg, oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, alkenyl succinic acid, adipic acid, sebacic acid, etc.) Alicyclic dicarboxylic acids (for example, cyclohexanedicarboxylic acid), aromatic dicarboxylic acids (for example, terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, etc.), their anhydrides, or lower (for example, having 1 or more carbon atoms) 5 or less) alkyl esters. Among these, as polyvalent carboxylic acid, aromatic dicarboxylic acid is preferable, for example.
The polyvalent carboxylic acid may be used in combination with a dicarboxylic acid or a trivalent or higher carboxylic acid having a crosslinked structure or a branched structure. Examples of the trivalent or higher carboxylic acid include trimellitic acid, pyromellitic acid, anhydrides thereof, and lower (for example, having 1 to 5 carbon atoms) alkyl esters.
Polyvalent carboxylic acid may be used individually by 1 type, and may use 2 or more types together.

Examples of the polyhydric alcohol include aliphatic diols (for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, etc.), alicyclic diols (for example, cyclohexanediol, cyclohexanedimethanol, Hydrogenated bisphenol A, etc.) and aromatic diols (for example, ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, etc.). Among these, as the polyhydric alcohol, for example, aromatic diols and alicyclic diols are preferable, and aromatic diols are more preferable.
As the polyhydric alcohol, a trihydric or higher polyhydric alcohol having a crosslinked structure or a branched structure may be used together with the diol. Examples of the trihydric or higher polyhydric alcohol include glycerin, trimethylolpropane, and pentaerythritol.
A polyhydric alcohol may be used individually by 1 type, and may use 2 or more types together.

The glass transition temperature (Tg) of the polyester resin is preferably 50 ° C. or higher and 80 ° C. or lower, and more preferably 50 ° C. or higher and 65 ° C. or lower.
The glass transition temperature is determined from a DSC curve obtained by differential scanning calorimetry (DSC), and more specifically described in the method for determining the glass transition temperature in JIS K 7121-1987 “Method for Measuring Plastic Transition Temperature”. Of “extrapolated glass transition start temperature”.

The weight average molecular weight (Mw) of the polyester resin is preferably from 5,000 to 1,000,000, and more preferably from 7,000 to 500,000.
The number average molecular weight (Mn) of the polyester resin is preferably from 2,000 to 100,000.
The molecular weight distribution Mw / Mn of the polyester resin is preferably 1.5 or more and 100 or less, and more preferably 2 or more and 60 or less.
The weight average molecular weight and the number average molecular weight are measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC is performed with a THF solvent using a Tosoh GPC / HLC-8120GPC as a measuring device and a Tosoh column / TSKgel SuperHM-M (15 cm). The weight average molecular weight and the number average molecular weight are calculated using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample from this measurement result.

The polyester resin is obtained by a well-known manufacturing method. Specifically, for example, the polymerization temperature is set to 180 ° C. or higher and 230 ° C. or lower, the pressure in the reaction system is reduced as necessary, and the reaction is performed while removing water and alcohol generated during the condensation.
In addition, when the monomer of the raw material is not dissolved or compatible at the reaction temperature, a solvent having a high boiling point may be added and dissolved as a solubilizing agent. In this case, the polycondensation reaction is performed while distilling off the solubilizer. If a monomer with poor compatibility is present in the copolymerization reaction, the monomer with poor compatibility and the monomer and the acid or alcohol to be polycondensed are condensed in advance and then polymerized together with the main component. It is good to condense.

  Here, examples of the polyester resin include modified polyester resins in addition to the above-described unmodified polyester resins. The modified polyester resin is a polyester resin in which a bonding group other than an ester bond is present, or a polyester resin in which a resin component different from the polyester resin component is bonded by a covalent bond or an ionic bond. Examples of the modified polyester include a resin in which a functional group such as an isocyanate group that reacts with an acid group or a hydroxyl group is introduced at the terminal, and a resin in which the terminal is modified by reacting with an active hydrogen compound.

  As the modified polyester resin, a urea-modified polyester resin is particularly preferable. By including a urea-modified polyester resin as the binder resin, the glitter of the image is high, and the occurrence of dullness in the glitter image is easily suppressed. This is because it is considered that the occurrence of peeling at the interface between the release agent and the binder resin during fixing is suppressed by the crosslinked structure of the urea-modified polyester resin. In this respect, the content of the urea-modified polyester resin is preferably 5% by mass or more and 50% by mass or less, and more preferably 7% by mass or more and 20% by mass or less with respect to the total binder resin.

  The urea-modified polyester resin is preferably a urea-modified polyester resin obtained by a reaction between a polyester resin having an isocyanate group (polyester prepolymer) and an amine compound (at least one of a crosslinking reaction and an extension reaction). Note that the urea-modified polyester resin may contain a urethane bond together with a urea bond.

  Examples of the polyester prepolymer having an isocyanate group include a polyester which is a polycondensate of a polyvalent carboxylic acid and a polyhydric alcohol, and a prepolymer obtained by reacting a polyvalent isocyanate compound with a polyester having active hydrogen. . Examples of the group having active hydrogen in the polyester include hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like, and alcoholic hydroxyl groups are preferable.

  In the polyester prepolymer having an isocyanate group, examples of the polyvalent carboxylic acid and polyhydric alcohol include the same compounds as the polyvalent carboxylic acid and polyhydric alcohol described in the polyester resin.

Examples of the polyvalent isocyanate compound include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); aromatic Diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates; polyisocyanates such as phenol derivatives, oximes, caprolactams What blocked with the blocking agent is mentioned.
A polyvalent isocyanate compound may be used individually by 1 type, and may use 2 or more types together.

  The ratio of the polyvalent isocyanate compound is preferably 1/1 or more and 5/1 or less as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester prepolymer having a hydroxyl group. Preferably it is 1.2 / 1 or more and 4/1 or less, More preferably, it is 1.5 / 1 or more and 2.5 / 1 or less. When [NCO] / [OH] is set to 1/1 or more and 5/1 or less, excessive exudation of the release agent is suppressed, and dullness of the glitter image is easily suppressed. When [NCO] / [OH] is set to 5 or less, a decrease in low-temperature fixability is easily suppressed.

  In the polyester prepolymer having an isocyanate group, the content of the component derived from the polyvalent isocyanate compound is preferably 0.5% by mass or more and 40% by mass or less, more preferably, based on the entire polyester prepolymer having an isocyanate group. 1 mass% or more and 30 mass% or less, More preferably, they are 2 mass% or more and 20 mass% or less. When the content of the component derived from the polyvalent isocyanate is 0.5% by mass or more and 40% by mass or less, excessive exudation of the release agent is suppressed, and dullness of the glitter image is easily suppressed. Note that when the content of the component derived from the polyvalent isocyanate is 40% by mass or less, a decrease in low-temperature fixability is easily suppressed.

  The number of isocyanate groups contained per molecule of the polyester prepolymer having an isocyanate group is preferably 1 or more on average, more preferably 1.5 or more and 3 or less, and even more preferably 1.8 or more on average. .5 or less. When the number of isocyanate groups is 1 or more per molecule, the molecular weight of the urea-modified polyester resin after the reaction increases, the excessive exudation of the release agent is suppressed, and the occurrence of dullness in the glitter image is easily suppressed. .

  Examples of the amine compound that reacts with the polyester prepolymer having an isocyanate group include diamine, trivalent or higher polyamine, amino alcohol, amino mercaptan, amino acid, and compounds in which these amino groups are blocked.

Examples of the diamine include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, isophoronediamine, etc. ); And aliphatic diamines (ethylenediamine, tetramethylenediamine, hexamethylenediamine, etc.) and the like.
Examples of the trivalent or higher polyamine include diethylenetriamine and triethylenetetramine.
Examples of amino alcohols include ethanolamine and hydroxyethylaniline.
Examples of amino mercaptans include aminoethyl mercaptan and aminopropyl mercaptan.
Examples of amino acids include aminopropionic acid and aminocaproic acid.
These amino group-blocked ones include ketimine compounds obtained from amine compounds such as diamines, trivalent or higher polyamines, amino alcohols, amino mercaptans, amino acids and ketone compounds (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), Examples include oxazoline compounds.
Of these amine compounds, ketimine compounds are preferred.
An amine compound may be used individually by 1 type, and may use 2 or more types together.

Note that the urea-modified polyester resin is a polyester resin having an isocyanate group (polyester prepolymer) by a stopper that stops at least one of a crosslinking reaction and an extension reaction (hereinafter also referred to as “crosslinking / extension reaction stopper”). It may be a resin in which the molecular weight after the reaction is adjusted by adjusting the reaction with the amine compound (at least one of a crosslinking reaction and an extension reaction).
Examples of the crosslinking / elongation reaction terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those blocked (ketimine compounds).

  The ratio of the amine compound is preferably 1/2 or more and 2 as an equivalent ratio [NCO] / [NHx] of the isocyanate group [NCO] in the polyester prepolymer having an isocyanate group and the amino group [NHx] in the amines. / 1 or less, more preferably from 1 / 1.5 to 1.5 / 1, and even more preferably from 1 / 1.2 to 1.2 / 1. When [NCO] / [NHx] is within the above range, the molecular weight of the urea-modified polyester resin after the reaction is increased, the excessive exudation of the release agent is suppressed, and the occurrence of dullness in the glittering image is easily suppressed.

  The glass transition temperature of the urea-modified polyester resin is preferably 40 ° C. or higher and 65 [° C.] or lower, and more preferably 45 ° C. or higher and 60 ° C. or lower. The number average molecular weight is preferably 2500 or more and 50000 or less, and more preferably 2500 or more and 30000 or less. The weight average molecular weight is preferably 10,000 to 500,000, more preferably 30,000 to 100,000.

  The content of the binder resin is, for example, preferably 40% by mass to 95% by mass, more preferably 50% by mass to 90% by mass, and further preferably 60% by mass to 85% by mass with respect to the entire toner particles. preferable.

-Bright pigment-
Examples of the bright pigment include pigments (bright pigments) that can give a bright feeling such as metallic luster. Specific examples of the bright pigment include metal powders such as aluminum (metal of Al alone), brass, bronze, nickel, stainless steel, zinc; mica coated with titanium oxide, yellow iron oxide, etc .; barium sulfate, layered silica Coated flaky inorganic crystal substrates such as silicates and layered aluminum silicates; single crystal plate-like titanium oxide; basic carbonates; bismuth oxychloride chloride; natural guanine; flaky glass powder; A powder etc. are mentioned and there will be no restriction | limiting in particular if it has glitter.
Among the bright pigments, metal powder is preferable from the viewpoint of specular reflection strength, and aluminum is most preferable among them.

The shape of the glitter pigment is a flat shape (scale shape).
The average length in the major axis direction of the glitter pigment is preferably 1 μm or more and 30 μm or less, more preferably 3 μm or more and 20 μm or less, and further preferably 5 μm or more and 15 μm or less.
The ratio of the average length in the major axis direction (aspect ratio) when the average length in the thickness direction of the glitter pigment is 1 is preferably 5 or more and 200 or less, more preferably 10 or more and 100 or less, More preferably, it is 30 or more and 70 or less.

  Each average length and aspect ratio of the glitter pigment are measured by the following methods. Using a scanning electron microscope (S-4800, manufactured by Hitachi High-Technologies Corporation), a photograph of the pigment particles was taken at a measurable magnification (300 to 100,000 times), and the resulting pigment particle image was two-dimensional. In such a state, the length in the major axis direction and the length in the thickness direction of each particle are measured, and the average length and the aspect ratio in the major axis direction of the glitter pigment are calculated.

  The content of the glitter pigment is, for example, preferably from 1 part by weight to 50 parts by weight, and more preferably from 15 parts by weight to 25 parts by weight with respect to 100 parts by weight of the toner particles.

-Release agent-
Examples of mold release agents include hydrocarbon waxes; natural waxes such as carnauba wax, rice wax, and candelilla wax; synthetic or mineral / petroleum waxes such as montan wax; and ester waxes such as fatty acid esters and montanic acid esters. And so on. The release agent is not limited to this.

  Among these, from the point that the exposure rate of the release agent is within the above range and the excessive exudation from the toner particles is suppressed (that is, the occurrence of dullness of the glitter image), paraffin wax, natural wax, polyethylene A release agent having a low polarity such as is preferable.

The melting temperature of the release agent is preferably 50 ° C. or higher and 110 ° C. or lower, and more preferably 60 ° C. or higher and 100 ° C. or lower.
The melting temperature is obtained from the DSC curve obtained by differential scanning calorimetry (DSC) according to “melting peak temperature” described in JIS K 1721-1987 “Method for measuring the melting temperature of plastics”. .

  The content of the release agent is, for example, preferably 1% by mass to 20% by mass and more preferably 5% by mass to 15% by mass with respect to the entire toner particles.

-Other additives-
Examples of other additives include well-known additives such as magnetic substances, charge control agents, inorganic particles, and other colorants other than the luster pigment. These additives are contained in the toner particles as internal additives.

  Examples of the charge control agent include quaternary ammonium salt compounds, nigrosine compounds, dyes containing complexes of aluminum, iron, chromium, and triphenylmethane pigments.

  As the inorganic particles, for example, known inorganic particles such as silica particles, titanium oxide particles, alumina particles, cerium oxide particles, or those obtained by hydrophobizing the surface thereof may be used alone or in combination of two or more. Good. Among these, silica particles having a refractive index smaller than that of the binder resin are preferably used. Further, the silica particles may be subjected to various surface treatments, and for example, those subjected to surface treatment with a silane coupling agent, a titanium coupling agent, a silicone oil or the like are preferably used.

  Examples of other colorants other than the luster pigment include known colorants, and are selected according to the target color. In addition, as another coloring agent, the coloring agent surface-treated as needed may be used, and you may use together with a dispersing agent.

-Toner particle characteristics-
The toner particles may be toner particles having a single layer structure, or toner particles having a so-called core / shell structure composed of a core (core particle) and a coating layer (shell layer) covering the core. May be.
The toner particles having a core / shell structure include, for example, a core including a glitter pigment, a binder resin, a release agent, and other additives as necessary, and a coating layer including the binder resin. It is good to be.

-Average maximum thickness C and average equivalent circle diameter D of toner particles
The toner particles are preferably flat and have an average equivalent circle diameter D longer than their average maximum thickness C. The ratio (C / D) of the average maximum thickness C to the average equivalent circle diameter D is preferably in the range of 0.001 to 0.500, and more preferably in the range of 0.010 to 0.200. A range of 0.050 or more and 0.100 or less is particularly preferable.
When the ratio (C / D) is 0.001 or more, the strength of the toner is ensured, breakage due to stress during image formation is suppressed, charging is reduced due to exposure of the pigment, and fog is generated as a result. Is suppressed. On the other hand, when it is 0.500 or less, excellent glitter can be obtained.

The average maximum thickness C and the average equivalent circle diameter D are measured by the following methods.
The toner particles are placed on a smooth surface and shaken to disperse the toner particles without unevenness. For 1000 toner particles, the maximum thickness C of the glittering toner particles and the equivalent circle diameter D of the surface viewed from above are measured by a color laser microscope “VK-9700” (manufactured by Keyence Corporation). And it calculates by calculating | requiring those arithmetic mean values.

The angle between the major axis direction of the toner particle cross section and the major axis direction of the glitter pigment When the section of the toner particle in the thickness direction is observed, the major axis direction of the toner particle and the length of the glitter pigment are measured. It is preferable that the ratio (based on the number) of the glitter pigment in which the angle with the axial direction is in the range of −30 ° to + 30 ° is 60% or more of the total glitter pigment to be observed. Further, the ratio is more preferably 70% or more and 95% or less, and particularly preferably 80% or more and 90% or less.
When the ratio is 60% or more, excellent glitter can be obtained.

Here, a method for observing the cross section of the toner particles will be described.
After embedding the toner particles with a bisphenol A liquid epoxy resin and a curing agent, a cutting sample is prepared. Next, the cutting sample is cut at −100 ° C. using a cutting machine using a diamond knife, for example, an ultramicrotome apparatus (Ultracut UCT, manufactured by Leica) to prepare an observation sample. The observation sample is observed with an ultrahigh resolution field emission scanning electron microscope (S-4800, manufactured by Hitachi High-Technologies Corporation) at a magnification at which about 1 to 10 toner particles can be seen in one field of view.
Specifically, the cross section of the toner particles (the cross section along the thickness direction of the toner particles) is observed, and for the 100 toner particles observed, the long axis direction of the cross section of the toner particles and the long axis direction of the glitter pigment. The number of glitter pigments with an angle between −30 ° and + 30 ° is determined by using image analysis software such as image analysis software (Wim ROOF) manufactured by Mitani Shoji Co., Ltd. or an output sample of an observation image and a protractor And calculate the ratio.

  The “major axis direction in the cross section of the toner particles” means a direction orthogonal to the thickness direction of the toner particles having an average equivalent circle diameter D longer than the average maximum thickness C described above. The “long axis direction” represents the length direction of the glitter pigment.

  The volume average particle diameter of the toner particles is desirably 1 μm or more and 30 μm or less, and more desirably 3 μm or more and 20 μm or less.

The volume average particle diameter D _50v of the toner particles is the volume and number of the particle size range (channel) divided based on the particle size distribution measured by a measuring device such as Multisizer II (Coulter). Each is obtained by drawing a cumulative distribution from the small diameter side. The particle diameter that is 16% cumulative is defined as volume D _16v and number D _16p , the particle diameter that is cumulative 50% is _defined as volume D _50v and number D _50p , and the particle diameter that is cumulative 84% is defined as volume D _84v and number D _84p . . Using these, the volume average particle size distribution index (GSDv) is calculated as ( _D84v / _D16v ) ^1/2 .

(External additive)
Examples of the external additive include inorganic particles. As the inorganic particles, SiO ₂ , TiO ₂ , Al ₂ O ₃ , CuO, ZnO, SnO ₂ , CeO ₂ , Fe ₂ O ₃ , MgO, BaO, CaO, K ₂ O, Na ₂ O, ZrO ₂ , CaO. _{SiO 2, K 2 O · (} TiO 2) n, Al 2 O 3 · 2SiO 2, CaCO 3, MgCO 3, BaSO 4, MgSO 4 , and the like.

The surface of the inorganic particles as an external additive is preferably subjected to a hydrophobic treatment. The hydrophobic treatment is performed, for example, by immersing inorganic particles in a hydrophobic treatment agent. The hydrophobizing agent is not particularly limited, and examples thereof include silane coupling agents, silicone oils, titanate coupling agents, aluminum coupling agents and the like. These may be used individually by 1 type and may use 2 or more types together.
The amount of the hydrophobizing agent is usually 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the inorganic particles, for example.

  Examples of external additives include resin particles (resin particles such as polystyrene, polymethyl methacrylate (PMMA), and melamine resin), cleaning activators (for example, metal salts of higher fatty acids typified by zinc stearate, fluorine-based high molecular weight substances). Particle) and the like.

  The external addition amount of the external additive is, for example, preferably 0.01% by mass or more and 5% by mass or less, and more preferably 0.01% by mass or more and 2.0% by mass or less with respect to the toner particles.

(Toner production method)
Next, a toner manufacturing method according to this embodiment will be described.
The toner according to the exemplary embodiment can be obtained by externally adding an external additive to the toner particles after producing toner particles containing a luster pigment.

  The toner particles may be produced by any of a dry production method (for example, a kneading pulverization method) and a wet production method (for example, an aggregation coalescence method, a suspension polymerization method, a dissolution suspension method, etc.). The production method of the toner particles is not particularly limited, and a known production method is adopted.

For example, in the dissolution suspension method, a liquid in which raw materials (resin particles, bright pigment, release agent, etc.) constituting toner particles are dissolved or dispersed in an organic solvent in which the binder resin can be dissolved is dispersed in particles. In this method, toner particles are granulated by dispersing in an aqueous solvent containing an agent and then removing the organic solvent.
In addition, the emulsion aggregation method is a method of forming toner particles through an aggregation step of forming aggregates of raw materials (resin particles, bright pigment, release agent, etc.) constituting the toner particles and a fusion step of fusing the aggregates. How to get.

  Among these, toner particles containing a urea-modified polyester resin as a binder resin are preferably obtained by the following dissolution suspension method. Although a method for obtaining toner particles containing unmodified polyester resin and urea-modified polyester resin as the binder resin will be described, the toner particles may contain only urea-modified polyester resin as the binder resin.

[Oil phase liquid preparation process]
An oil phase liquid prepared by dissolving or dispersing a toner particle material containing an unmodified polyester resin, a polyester prepolymer having an isocyanate group, an amine compound, a bright pigment, and a release agent in an organic solvent is prepared (oil phase liquid preparation step) ). In the oil phase liquid preparation step, the toner particle material is dissolved or dispersed in an organic solvent to obtain a mixed liquid of the toner material.

  The oil phase liquid is prepared by 1) a method in which toner materials are collectively dissolved or dispersed in an organic solvent, and 2) a toner material is previously kneaded and then the kneaded product is dissolved or dispersed in an organic solvent. 3) A method of adjusting an unmodified polyester resin, a polyester prepolymer having an isocyanate group, an amine compound dissolved in an organic solvent, and then dispersing a glittering pigment and a release agent in the organic solvent, 4) A method in which a glitter pigment and a release agent are dispersed in an organic solvent, and then an unmodified polyester resin, a polyester prepolymer having an isocyanate group, and an amine compound are dissolved in the organic solvent, and 5) an isocyanate. Toner particle materials (unmodified polyester resin, glitter pigment, and release agent) other than polyester prepolymers having amine groups and amine compounds are organically dissolved. 6) A method for preparing a polyester prepolymer having an isocyanate group and an amine compound in this organic solvent, and 6) toner particle material other than the polyester prepolymer having an isocyanate group or the amine compound (not yet prepared). Examples include a method in which a modified polyester resin, a bright pigment, and a release agent) are dissolved or dispersed in an organic solvent, and then the polyester prepolymer or amine compound having an isocyanate group is dissolved in the organic solvent. . The method for preparing the oil phase liquid is not limited to these.

  Examples of the organic solvent for the oil phase liquid include ester solvents such as methyl acetate and ethyl acetate; ketone solvents such as methyl ethyl ketone and methyl isopropyl ketone; aliphatic hydrocarbon solvents such as hexane and cyclohexane; dichloromethane, chloroform, trichloroethylene, and the like Examples thereof include halogenated hydrocarbon solvents. These organic solvents are those that dissolve the binder resin, have a ratio of dissolving in water of about 0% by mass to 30% by mass, and preferably have a boiling point of 100 ° C. or less. Of these organic solvents, ethyl acetate is preferred.

[Suspension preparation process]
Next, the obtained oil phase liquid is dispersed in an aqueous phase liquid to prepare a suspension (suspension preparation step).
Along with the preparation of the suspension, the polyester prepolymer having an isocyanate group is reacted with the amine compound. This reaction produces a urea-modified polyester resin. This reaction is accompanied by at least one of a molecular chain crosslinking reaction and an extension reaction. In addition, you may perform reaction of the polyester prepolymer which has this isocyanate group, and an amine compound with the organic solvent removal process mentioned later.
Here, the reaction conditions are selected depending on the reactivity between the isocyanate group structure of the polyester prepolymer and the amine compound. As an example, the reaction time is preferably 10 minutes to 40 hours, and more preferably 2 hours to 24 hours. The reaction temperature is preferably 0 ° C. or higher and 150 ° C. or lower, and preferably 40 ° C. or higher and 98 ° C. or lower. In addition, you may use a well-known catalyst (Dibutyltin laurate, a dioctyltin laurate, etc.) as needed for the production | generation of a urea modified polyester resin. That is, the catalyst may be added to the oil phase liquid or suspension.

  Examples of the aqueous phase liquid include an aqueous phase liquid in which a particle dispersant such as an organic particle dispersant and an inorganic particle dispersant is dispersed in an aqueous solvent. Examples of the aqueous phase liquid include an aqueous phase liquid in which the particle dispersant is dispersed in an aqueous solvent and the polymer dispersant is dissolved in the aqueous solvent. In addition, you may add well-known additives, such as surfactant, to an aqueous phase liquid.

  Examples of the aqueous solvent include water (for example, usually ion-exchanged water, distilled water, and pure water). An aqueous solvent is a solvent containing water and an organic solvent such as alcohol (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.). There may be.

  Examples of the organic particle dispersant include hydrophilic organic particle dispersants. Examples of the organic particle dispersant include particles of poly (meth) acrylic acid alkyl ester resin (for example, polymethyl methacrylate resin), polystyrene resin, poly (styrene-acrylonitrile) resin, and the like. Examples of the organic particle dispersant include styrene acrylic resin particles.

  Examples of the inorganic particle dispersant include hydrophilic inorganic particle dispersants. Specific examples of the inorganic particle dispersant include particles of silica, alumina, titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, clay, diatomaceous earth, bentonite, and the like, but calcium carbonate particles are preferable. An inorganic particle dispersing agent may be used individually by 1 type, and may use 2 or more types together.

The particle dispersant may be surface-treated with a polymer having a carboxyl group on the surface.
As the polymer having a carboxyl group, the carboxyl group of an α, β-monoethylenically unsaturated carboxylic acid or α, β-monoethylenically unsaturated carboxylic acid is an alkali metal, alkaline earth metal, ammonium, amine, or the like. And a copolymer of at least one selected from neutralized salts (alkali metal salts, alkaline earth metal salts, ammonium salts, amine salts, etc.) and α, β-monoethylenically unsaturated carboxylic acid esters. It is done. As the polymer having a carboxyl group, the carboxyl group of a copolymer of an α, β-monoethylenically unsaturated carboxylic acid and an α, β-monoethylenically unsaturated carboxylic acid ester is an alkali metal or an alkaline earth metal. And salts neutralized with ammonium, amine, etc. (alkali metal salts, alkaline earth metal salts, ammonium salts, amine salts, etc.). The said polymer which has a carboxyl group may be used individually by 1 type, and may use 2 or more types together.

  Typical α, β-monoethylenically unsaturated carboxylic acids include α, β-unsaturated monocarboxylic acids (acrylic acid, methacrylic acid, crotonic acid, etc.), α, β-unsaturated dicarboxylic acids (maleic acid). Acid, fumaric acid, itaconic acid, etc.). Representative examples of α, β-monoethylenically unsaturated carboxylic acid esters include alkyl esters of (meth) acrylic acid, (meth) acrylates having an alkoxy group, (meth) acrylates having a cyclohexyl group, Examples include (meth) acrylate having a hydroxy group, polyalkylene glycol mono (meth) acrylate, and the like.

  Examples of the polymer dispersant include hydrophilic polymer dispersants. Specifically, as the polymer dispersant, a polymer dispersant having a carboxyl group and having no lipophilic group (hydroxypropoxy group, methoxy group, etc.) (for example, water-soluble carboxymethyl cellulose, carboxyethyl cellulose, etc.) ).

[Solvent removal step]
Next, the organic solvent is removed from the obtained suspension to obtain a toner particle dispersion (solvent removal step). In this solvent removal step, the organic solvent contained in the droplets of the aqueous phase liquid dispersed in the suspension is removed to generate toner particles. The removal of the organic solvent from the suspension may be performed immediately after the suspension preparation step, or may be performed after 1 minute or more has elapsed after completion of the suspension preparation step.
In the solvent removal step, the organic solvent is preferably removed from the suspension by cooling or heating the obtained suspension in a range of, for example, 0 ° C. or more and 100 ° C. or less.

Specific methods for removing the organic solvent include the following methods.
(1) A method of forcibly renewing the gas phase on the surface of the suspension by blowing an air stream on the suspension. In this case, gas may be blown into the suspension.
(2) A method of reducing the pressure. In this case, the gas phase on the surface of the suspension may be forcibly updated by filling with gas, or gas may be blown into the suspension.

Through the above steps, toner particles are obtained.
Here, after completion of the solvent removal step, toner particles formed in the toner particle dispersion are dried through a known washing step, solid-liquid separation step, and drying step to obtain toner particles.
In the washing step, it is preferable to sufficiently carry out substitution washing with ion-exchanged water from the viewpoint of chargeability.
The solid-liquid separation step is not particularly limited, but suction filtration, pressure filtration, etc. are preferably performed from the viewpoint of productivity. Also, the drying process is not particularly limited, but from the viewpoint of productivity, freeze drying, flash jet drying, fluidized drying, vibration fluidized drying, or the like is preferably performed.

The toner according to the exemplary embodiment is manufactured, for example, by adding an external additive to the obtained dry toner particles and mixing them.
Mixing is preferably performed by, for example, a V blender, a Henschel mixer, a Laedige mixer, or the like.
Further, if necessary, coarse toner particles may be removed using a vibration sieving machine, a wind sieving machine, or the like.

<Electrostatic image developer>
The electrostatic charge image developer according to the exemplary embodiment includes at least the toner according to the exemplary embodiment.
The electrostatic image developer according to this embodiment may be a one-component developer including only the toner according to this embodiment, or may be a two-component developer mixed with the toner and a carrier.

There is no restriction | limiting in particular as a carrier, A well-known carrier is mentioned. Examples of carriers include a coated carrier in which the surface of a core made of magnetic powder is coated with a resin; a magnetic powder-dispersed carrier in which magnetic powder is dispersed in a matrix resin; and a porous magnetic powder impregnated with resin. Resin impregnated type carriers; and the like.
The magnetic powder-dispersed carrier and the resin-impregnated carrier may be carriers in which the constituent particles of the carrier are used as a core and the surface is coated with a resin.

  Examples of the magnetic powder include magnetic metals such as iron, nickel, and cobalt; magnetic oxides such as ferrite and magnetite.

Examples of the coating resin and matrix resin include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic. Examples include an acid copolymer, a straight silicone resin containing an organosiloxane bond or a modified product thereof, a fluororesin, a polyester, a polycarbonate, a phenol resin, and an epoxy resin. The coating resin and the matrix resin may contain additives such as conductive particles.
Examples of the conductive particles include metals such as gold, silver, and copper; particles such as carbon black, titanium oxide, zinc oxide, tin oxide, barium sulfate, aluminum borate, and potassium titanate.

  In order to coat the surface of the core material with a resin, a method of coating with a coating layer forming solution in which a coating resin and various additives (used as necessary) are dissolved in an appropriate solvent may be mentioned. The solvent is not particularly limited, and may be selected in consideration of the type of resin used, application suitability, and the like. Specific resin coating methods include a dipping method in which a core material is immersed in a coating layer forming solution; a spray method in which the coating layer forming solution is sprayed on the surface of the core material; Examples thereof include a fluidized bed method in which a coating layer forming solution is sprayed; a kneader coater method in which a carrier core material and a coating layer forming solution are mixed in a kneader coater, and then the solvent is removed.

  The mixing ratio (mass ratio) of the toner and the carrier in the two-component developer is preferably toner: carrier = 1: 100 to 30: 100, and more preferably 3: 100 to 20: 100.

<Image Forming Apparatus / Image Forming Method>
The image forming apparatus / image forming method according to the present embodiment will be described.
The image forming apparatus according to the present embodiment includes an image carrier, a charging unit that charges the surface of the image carrier, an electrostatic image forming unit that forms an electrostatic image on the surface of the charged image carrier, and an electrostatic charge. Development means for containing an image developer and developing the electrostatic image formed on the surface of the image carrier as a toner image with the electrostatic image developer, and the toner image formed on the surface of the image carrier as a recording medium Transfer means for transferring to the surface of the recording medium, and fixing means for fixing the toner image transferred to the surface of the recording medium.
The electrostatic charge image developer according to this embodiment is applied as the electrostatic charge image developer.

  In the image forming apparatus according to this embodiment, a charging process for charging the surface of the image carrier, an electrostatic charge image forming process for forming an electrostatic image on the surface of the charged image carrier, and an electrostatic charge according to this embodiment. A developing step of developing an electrostatic charge image formed on the surface of the image carrier as a toner image with an image developer; a transfer step of transferring the toner image formed on the surface of the image carrier to the surface of the recording medium; An image forming method (an image forming method according to the present embodiment) including a fixing step of fixing the toner image transferred onto the surface of the recording medium is performed.

The image forming apparatus according to the present embodiment is a direct transfer type apparatus that directly transfers a toner image formed on the surface of an image carrier to a recording medium; the toner image formed on the surface of the image carrier is transferred to an intermediate transfer member An intermediate transfer type apparatus that primarily transfers the toner image transferred to the surface of the intermediate transfer body and then secondary transfer the toner image to the surface of the recording medium; after the toner image is transferred, the surface of the image carrier before charging is cleaned. An apparatus provided with a cleaning unit; a known image forming apparatus such as an apparatus provided with a charge removing unit that discharges the surface of an image holding member by irradiating a discharge light after charging a toner image and before charging is applied.
In the case of an intermediate transfer type apparatus, the transfer means includes, for example, an intermediate transfer body on which a toner image is transferred to the surface, and a primary transfer that primarily transfers the toner image formed on the surface of the image holding body to the surface of the intermediate transfer body. And a secondary transfer unit that secondarily transfers the toner image transferred onto the surface of the intermediate transfer member onto the surface of the recording medium.

  In the image forming apparatus according to the present embodiment, for example, the part including the developing unit may have a cartridge structure (process cartridge) that is detachable from the image forming apparatus. As the process cartridge, for example, a process cartridge that accommodates the electrostatic charge image developer according to this embodiment and includes a developing unit is preferably used.

Hereinafter, an example of the image forming apparatus according to the present embodiment will be described, but the present invention is not limited thereto. In addition, the main part shown to a figure is demonstrated and the description is abbreviate | omitted about others.
FIG. 2 is a schematic configuration diagram illustrating an embodiment of an image forming apparatus including a developing device to which the electrostatic charge image developer according to the present embodiment is applied.
In FIG. 1, the image forming apparatus according to the present embodiment has a photosensitive drum 20 as an image holding body that rotates in a predetermined direction, and the photosensitive drum 20 is charged around the photosensitive drum 20. For example, an exposure device 22 as an electrostatic charge image forming device for forming an electrostatic charge image Z on the photosensitive drum 20, and a visible image of the electrostatic charge image Z formed on the photosensitive drum 20. Developing device 30, transfer device 24 for transferring a toner image visualized on the photosensitive drum 20 to recording paper 28 as a recording medium, and cleaning device for cleaning residual toner on the photosensitive drum 20 25 are sequentially arranged.

In the present embodiment, as shown in FIG. 2, the developing device 30 has a developing housing 31 in which a developer G containing toner 40 is accommodated, and the developing housing 31 is developed to face the photosensitive drum 20. A developing roll (developing electrode) 33 serving as a toner holding member facing the developing opening 32 and applying a predetermined developing bias to the developing roll 33. A developing electric field is formed in a region (developing region) sandwiched between the photosensitive drum 20 and the developing roll 33. Further, a charge injection roll (injection electrode) 34 as a charge injection member is provided in the development housing 31 so as to face the development roll 33. In particular, in the present embodiment, the charge injection roll 34 also serves as a toner supply roll for supplying the toner 40 to the developing roll 33.
Here, the rotation direction of the charge injection roll 34 may be selected. However, in consideration of the toner supply property and the charge injection characteristic, the charge injection roll 34 has the same direction at the portion facing the developing roll 33. In addition, it is preferable that the rotation is performed with a peripheral speed difference (for example, 1.5 times or more), the toner 40 is sandwiched between regions where the charge injection roll 34 and the developing roll 33 are sandwiched, and the charge is injected while sliding.

Next, the operation of the image forming apparatus according to the embodiment will be described.
When the image forming process is started, first, the surface of the photosensitive drum 20 is charged by the charging device 21, and the exposure device 22 writes the electrostatic charge image Z on the charged photosensitive drum 20, and the developing device 30 makes the static image. The charge image Z is visualized as a toner image. Thereafter, the toner image on the photoconductive drum 20 is conveyed to a transfer site, and the transfer device 24 electrostatically transfers the toner image on the photoconductive drum 20 to a recording paper 28 as a recording medium. The residual toner on the photosensitive drum 20 is cleaned by the cleaning device 25. Thereafter, the toner image on the recording paper 28 is fixed by a fixing device 36 including a fixing member 36A (a fixing belt, a fixing roll, etc.) and a pressure member 36B, and an image is obtained.

<Process cartridge / toner cartridge>
The process cartridge according to this embodiment will be described.
The process cartridge according to the present embodiment accommodates the electrostatic image developer according to the present embodiment, and develops the electrostatic image formed on the surface of the image carrier as a toner image by the electrostatic image developer. And a process cartridge that can be attached to and detached from the image forming apparatus.

  Note that the process cartridge according to the present embodiment is not limited to the above-described configuration, and other means such as a developing device and other units such as an image carrier, a charging unit, an electrostatic charge image forming unit, and a transfer unit, if necessary. And at least one selected from the above.

  Hereinafter, an example of the process cartridge according to the present embodiment will be shown, but the present invention is not limited to this. In addition, the main part shown to a figure is demonstrated and the description is abbreviate | omitted about others.

FIG. 3 is a schematic configuration diagram showing a process cartridge according to the present embodiment.
The process cartridge 200 shown in FIG. 3 is provided around the photosensitive member 107 and the photosensitive member 107 by, for example, a housing 117 provided with an attachment rail 116 and an opening 118 for exposure. A charging roller 108 (an example of a charging unit), a developing device 111 (an example of a developing unit), and a photoconductor cleaning device 113 (an example of a cleaning unit) are integrally combined and held to form a cartridge. Yes.
In FIG. 3, reference numeral 109 denotes an exposure device (an example of an electrostatic charge image forming unit), 112 denotes a transfer device (an example of a transfer unit), 115 denotes a fixing device (an example of a fixing unit), and 300 denotes a recording paper (a recording medium). An example).

Next, the toner cartridge according to this embodiment will be described.
The toner cartridge according to the present exemplary embodiment may be configured to store the toner according to the present exemplary embodiment and be attached to and detached from the image forming apparatus. Note that the toner cartridge according to the present embodiment only needs to contain at least toner, and may contain developer, for example, depending on the mechanism of the image forming apparatus.

  The image forming apparatus shown in FIG. 2 is an image forming apparatus having a configuration in which a toner cartridge (not shown) can be freely attached and detached, and the developing device 30 is connected to the toner cartridge by a toner supply pipe (not shown). . Further, when the amount of toner stored in the toner cartridge is low, this toner cartridge may be replaced.

  Hereinafter, although an embodiment explains this embodiment in detail, this embodiment is not limited to these examples at all. In the following description, “part” and “%” are all based on mass unless otherwise specified.

(Preparation of unmodified polyester resin (1))
-Terephthalic acid: 1243 parts-Bisphenol A ethylene oxide adduct: 1830 parts-Bisphenol A propylene oxide adduct: 840 parts After mixing the above ingredients at 180 ° C, add 3 parts of dibutyltin oxide and heat at 220 ° C. While removing water, an unmodified polyester resin was obtained. The obtained unmodified polyester resin had a glass transition temperature Tg of 60 ° C., an acid value of 3 mgKOH / g, and a hydroxyl value of 1 mgKOH / g.

(Preparation of polyester prepolymer (1))
-Terephthalic acid: 1243 parts-Bisphenol A ethylene oxide adduct: 1830 parts-Bisphenol A propylene oxide adduct: 840 parts After mixing the above ingredients at 180 ° C, add 3 parts of dibutyltin oxide and heat at 220 ° C. While distilling off water, a polyester prepolymer was obtained. 350 parts of the obtained polyester prepolymer, 50 parts of tolylene diisocyanate and 450 parts of ethyl acetate were put in a container, and this mixture was heated at 130 ° C. for 3 hours to obtain a polyester prepolymer (1) having an isocyanate group (hereinafter referred to as “isocyanate”). Modified polyester prepolymer (1) ") was obtained.

(Preparation of ketimine compound (1))
A container was charged with 50 parts of methyl ethyl ketone and 150 parts of hexamethylenediamine, and stirred at 60 ° C. to obtain a ketimine compound (1).

(Preparation of glitter pigment dispersion (1))
Aluminum pigment (flat luster pigment, Showa Aluminum Powder Co., Ltd., 2173EA): 100 parts Ethyl acetate: 500 parts Mixing the above components, filtering the mixture and further mixing with 500 parts of ethyl acetate After repeating the process five times, the pigment dispersion liquid (1) in which the glitter pigment (aluminum pigment) is dispersed by dispersing for about 1 hour using an emulsifier / disperser Cavitron (manufactured by Taiheiyo Kiko Co., Ltd., CR1010) Solid content concentration: 10%) was obtained.

(Preparation of release agent dispersion (1))
Paraffin wax (melting temperature 89 ° C.): 30 parts Ethyl acetate: 270 parts In the state where the above components are cooled to 10 ° C., they are wet pulverized by a microbead type disperser (DCP mill), and a release agent dispersion (1 )

(Preparation of oil phase liquid (1))
Unmodified polyester resin (1): 136 parts Bright pigment dispersion (1): 500 parts Ethyl acetate: 56 parts After stirring and mixing the above components, the resulting mixture was mixed with a release agent dispersion (1) 75 Part was added and stirred to obtain an oil phase liquid (1).

(Preparation of styrene acrylic resin particle dispersion (1))
-Styrene: 370 parts-n-butyl acrylate: 30 parts-Acrylic acid: 4 parts-Dodecanethiol: 24 parts-Carbon tetrabromide: 4 parts The above components were mixed and dissolved into a nonionic surfactant ( Dispersed in a flask in an aqueous solution in which 6 parts of Sanyo Chemical Industries, Ltd .: Nonipol 400) and 10 parts of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) were dissolved in 560 parts of ion-exchanged water. After emulsification and mixing for 10 minutes, an aqueous solution in which 4 parts of ammonium persulfate was dissolved in 50 parts of ion-exchanged water was added thereto, and after nitrogen substitution, the contents were kept at 70 ° C. while stirring the flask. The mixture was heated in an oil bath until it became, and emulsion polymerization was continued for 5 hours. Thus, a styrene acrylic resin particle dispersion (1) (resin particle concentration: 40% by mass) obtained by dispersing resin particles having an average particle diameter of 180 nm and a weight average molecular weight (Mw) of 15,500 was obtained. The glass transition point of the styrene acrylic resin particles was 59 ° C.

(Preparation of aqueous phase liquid (1))
-Styrene acrylic resin particle dispersion (1): 60 parts-2% aqueous solution of Serogen BS-H (Daiichi Kogyo Seiyaku Co., Ltd.): 200 parts-Ion-exchanged water: 200 parts A liquid (1) was obtained.

<Example 1>
-Production of toner particles (1)-
・ Oil phase liquid (1): 300 parts ・ Isocyanate-modified polyester prepolymer (1): 25 parts ・ Ketimine compound (1): 0.5 part The above ingredients are put in a container and homogenizer (Ultra Turrax: manufactured by IKA). After stirring for 2 minutes to obtain an oil phase liquid (1P), 1000 parts of the aqueous phase liquid (1) was added to the container and stirred for 20 minutes with a homogenizer. Next, this mixed solution is stirred with a propeller type stirrer at room temperature (25 ° C.) and normal pressure (1 atm) for 48 hours to react the isocyanate-modified polyester prepolymer (1) with the ketimine compound (1), and urea While producing | generating the modified polyester resin, the organic solvent was removed and the granular material was formed. Next, the granular material was washed with water, dried and classified to obtain toner particles (1). The volume average particle diameter of the toner particles was 12 μm.

-Preparation of glitter toner (1)-
Toner particles (1): 100 parts, hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., RY50): 1.5 parts, and hydrophobic titanium oxide (manufactured by Nippon Aerosil Co., Ltd., T805): 1.0 part of sample mill For 30 seconds at 10,000 rpm. Thereafter, the toner was sieved with a vibration sieve having an opening of 45 μm to obtain a glittering toner (1).

<Example 2>
In the production of the toner particles (1), the toner particles (2) are the same as the toner particles (1) except that the release agent dispersion (1) added to the oil phase liquid (1) is changed from 75 parts to 90 parts. )
Then, a bright toner (2) was obtained in the same manner as the bright toner (1) except that the toner particles (2) were used.

<Example 3>
Toner particles (1) were prepared in the same manner as toner particles (1), except that the release agent dispersion (1) added to oil phase liquid (1) was changed from 75 parts to 106 parts. )
Then, a glittering toner (3) was obtained in the same manner as the glittering toner (1) except that the toner particles (3) were used.

<Example 4>
In the production of the toner particles (1), the toner particles (4) are the same as the toner particles (1) except that the release agent dispersion (1) added to the oil phase liquid (1) is changed from 75 parts to 118 parts. )
Then, a bright toner (4) was obtained in the same manner as the bright toner (1) except that the toner particles (4) were used.

<Example 5>
In preparation of the toner particles (1), instead of 25 parts of the isocyanate-modified polyester prepolymer (1) and 0.5 part of the ketimine compound (1), the unmodified polyester resin (1), 1800 parts and 1.8 parts of chloride Ion-crosslinkable polyester resin 25 obtained by mixing 1200 parts of an aqueous solution in which magnesium is dissolved with a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.), kneading the mixture at 130 ° C. for 2 hours with two rolls, rolling and cooling and pulverizing with a pulverizer. The toner particles (5) were obtained in the same manner as the toner particles (1) except that the toner particles (1) were used.
Then, a glittering toner (5) was obtained in the same manner as the glittering toner (1) except that the toner particles (5) were used.

<Example 6>
In the production of the toner particles (1), the parting agent dispersion (1) added to the oil phase liquid (1) is changed from 75 parts to 118 parts, and 25 parts of the isocyanate-modified polyester prepolymer (1), the ketimine compound (1) ) Instead of 0.5 part, unmodified polyester resin (1), 1800 parts, and 1200 parts of an aqueous solution containing 1.8 parts of magnesium chloride were mixed with a Henschel mixer (Mitsui Mining Co., Ltd.). Toner particles (6) were obtained in the same manner as toner particles (1), except that the rolls were kneaded at 130 ° C. for 2 hours, then rolled and cooled and pulverized with a pulverizer to 25 parts of ion-crosslinkable polyester resin. .
Then, a bright toner (6) was obtained in the same manner as the bright toner (1) except that the toner particles (6) were used.

<Comparative Example 1>
The toner particles (C1) were prepared in the same manner as the toner particles (1) except that the release agent dispersion (1) added to the oil phase liquid (1) was changed from 75 parts to 125 parts. )
Then, a bright toner (C1) was obtained in the same manner as the bright toner (1) except that the toner particles (C1) were used.

<Comparative Example 2>
Toner particles (1) were prepared in the same manner as toner particles (1) except that the release agent dispersion (1) added to the oil phase liquid (1) was changed from 75 parts to 133 parts. )
Then, a glittering toner (C2) was obtained in the same manner as the glittering toner (1) except that the toner particles (C2) were used.

<Measurement / Evaluation>
(Exposure rate of release agent)
With respect to the glittering toner obtained in each example, the exposure rate of the release agent on the surface of the toner particles was measured according to the method described above. The results are shown in Table 1.

(Development of developer)
The glitter toner (1) obtained in each example: 36 parts and carrier: 414 parts were put into a 2 liter V blender, stirred for 20 minutes, and then sieved at 212 μm to prepare a developer. In addition, the carrier obtained by the method shown below was used.

-Production of carrier-
Ferrite particles (volume average particle diameter: 35 μm): 100 parts Toluene: 14 parts Methyl methacrylate-perfluorooctylethyl acrylate copolymer (critical surface tension: 24 dyn / cm): 1.6 parts Carbon black (product) Name: VXC-72, manufactured by Cabot, volume resistivity: 100 Ωcm or less): 0.12 parts, crosslinked melamine resin particles (average particle size: 0.3 μm, toluene insoluble): 0.3 parts First, methyl methacrylate-par To the fluorooctylethyl acrylate copolymer, carbon black was diluted with toluene and dispersed with a sand mill. Next, each of the above components other than the ferrite particles was dispersed for 10 minutes with a stirrer to prepare a coating layer forming solution. Next, this coating layer forming solution and ferrite particles are put in a vacuum degassing type kneader and stirred at a temperature of 60 ° C. for 30 minutes, and then the pressure is reduced to distill off toluene to form a resin coating layer to obtain a carrier. It was.

(Evaluation)
The obtained developer was filled in a developing device of “color 800 press remodeling machine” manufactured by Fuji Xerox Co., Ltd.
Using this modified machine, 10,000 sheets of belt-like solid images were output on a paper of OK top coat paper (basis weight 127: manufactured by Oji Paper Co., Ltd.) with a loading amount of glitter toner of 4.5 g / m ² .

(Measurement of brightness: ratio (X / Y))
With respect to the solid image output to the 10,000th sheet, incident light with an incident angle of −45 ° to the solid image is incident using a spectroscopic variable angle color difference meter GC5000L manufactured by Nippon Denshoku Industries Co., Ltd. as a variable angle photometer. The reflectance A at the light receiving angle + 30 ° and the reflectance B at the light receiving angle −30 ° are measured. The reflectance A and reflectance B were measured at intervals of 20 nm for light having a wavelength in the range of 400 nm to 700 nm, and the average value of the reflectance at each wavelength was used. The ratio (X / Y) was calculated from these measurement results. The results are shown in Table 1.
The higher the ratio (X / Y), the higher the glitter feeling, and the lower the ratio (X / Y), the stronger the dull feeling and the less the feeling of glitter.

(Evaluation of dullness in the image)
The solid image output on the 10,000th sheet was observed, and the dullness of the image was evaluated based on the following evaluation criteria. The results are shown in Table 1.
A (◎): No image dullness observed from any angle.
B (◯): There are spots that appear dull locally when the angle is changed, but there is no problem in practical use.
C (△): When the angle is changed, a dull spot can be confirmed, which causes a problem in actual use.
D (x): Confirmed by visual dull image.

From the above results, it can be seen that in this example, the ratio (X / Y) is higher than in the comparative example, and dullness of the image is suppressed.
In particular, the glitter toners of Examples 1 to 4 containing urea-modified polyester resin in the toner particles have a ratio (X / Y) as compared with the glitter toners of Examples 5 to 6 not containing urea-modified polyester resin in the toner particles. It can be seen that dullness of the image is suppressed.

2 Toner particles 4 Bright pigment 20 Photosensitive drum 21 Charging device 22 Exposure device 24 Transfer device 25 Cleaning device 28, 300 Recording paper (an example of a recording medium)
30 developing device 31 developing housing 32 developing opening 33 developing roll 34 charge injection roll 36 fixing device 40 toner 107 photoconductor (an example of an image carrier)
108 Charging roll (an example of charging means)
109 Exposure apparatus (an example of electrostatic charge image forming means)
111 Developing device (an example of developing means)
112 Transfer device (an example of transfer means)
113 photoconductor cleaning device (an example of cleaning means)
115 Fixing device (an example of fixing means)
116 Mounting rail 117 Housing 118 Opening 200 for exposure Process cartridge

Claims (6)

Having toner particles including a binder resin, a flat glitter pigment and a release agent;
C1S spectrum intensity of the releasing agent exposed on the surface of the toner particles to the C1S spectrum strength of the surface of the toner particles as measured by X-ray photoelectron spectrometer (XPS) is located at 3.0% or less than 0% ,
The toner particles, as the binder resin, saw including a urea-modified polyester resin,
A glittering toner that the glitter pigment contains in the toner particles in contact with the urea-modified polyester resin .   An electrostatic charge image developer comprising the glitter toner according to claim 1. Containing the glitter toner according to claim 1;
A toner cartridge to be attached to and detached from the image forming apparatus. A developing unit that contains the electrostatic charge image developer according to claim 2 and that develops the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer,
A process cartridge attached to and detached from the image forming apparatus. An image carrier,
Charging means for charging the surface of the image carrier;
An electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image carrier;
A developing unit that contains the electrostatic charge image developer according to claim 2 and develops the electrostatic charge image formed on the surface of the image carrier as a toner image by the electrostatic charge image developer;
Transfer means for transferring a toner image formed on the surface of the image carrier to the surface of a recording medium;
Fixing means for fixing the toner image transferred to the surface of the recording medium;
An image forming apparatus comprising: A charging step for charging the surface of the image carrier;
An electrostatic charge image forming step of forming an electrostatic charge image on the surface of the charged image carrier;
A developing step of developing an electrostatic charge image formed on the surface of the image carrier as a toner image with the electrostatic charge image developer according to claim 2;
A transfer step of transferring a toner image formed on the surface of the image carrier to the surface of a recording medium;
A fixing step of fixing the toner image transferred to the surface of the recording medium;
An image forming method comprising: