JP6561443B2 - Glitter powder and method for producing the same, glitter toner, electrostatic charge image developer, toner cartridge, image forming method, and image forming apparatus - Google Patents

Description

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

Methods for visualizing image information through an electrostatic charge image, such as electrophotography, are currently used in various fields.
In conventional electrophotography, an electrostatic latent image is formed on a photosensitive member or an electrostatic recording body by using various means, and electro-sensitive particles called toner are attached to the electrostatic latent image to form an electrostatic latent image. Generally, a method of visualizing through a plurality of steps of developing an image (toner image), transferring it to the surface of a transfer medium, and fixing it by heating or the like is generally used.
Among toners, glittering toner is used for the purpose of forming an image having a brightness such as metallic luster.
As an example of the glitter toner, for example, when a solid image is formed, a light receiving angle + 30 ° measured when incident light having an incident angle of −45 ° is irradiated to the image by a goniophotometer. A toner in which the ratio (A / B) of the reflectance A to the reflectance B at a light receiving angle of −30 ° is 2 or more and 100 or less is known (see Patent Document 1).

JP 2012-32765 A

  The problem to be solved by the present invention is to provide a glitter powder having excellent glitter.

The above-described problems of the present invention have been solved by means described in the following <1> to <3> or <5> to <8>. It is described below together with <4> which is a preferred embodiment.
<1> The average equivalent circle diameter is 6 to 15 μm, the number of particles having an equivalent circle diameter of 4 μm or less is 20% by number or less, the average circularity is 0.900 to 0.980, and the circularity is 0. A glittering powder comprising a glittering pigment having a particle number of 850 or less and 20 number% or less,
<2> A dispersion step of dispersing the glitter pigment in the liquid, a classification step in which the dispersed glitter pigment is naturally settled to separate and classify a pigment having a slow sedimentation rate, and the classified glitter pigment is dispersed in the liquid. A method for producing the glittering powder according to <1>, including a separation step for further separation, wherein the dispersion step, the classification step, and the separation step are repeated twice or more.
<3> A glitter toner containing the glitter powder according to <1>,
<4> The bright toner according to <3>, wherein when the solid image is formed, the brightness of the image is 50 or more and 80 or less,
<5> The bright toner according to <3> or <4>, and an electrostatic charge image developer containing a carrier,
<6> A toner cartridge that is detachable from the image forming apparatus and contains the glitter toner according to <3> or <4>,
<7> A latent image forming step of forming an electrostatic latent image on the surface of the image carrier, a developing step of developing the electrostatic latent image formed on the surface of the image carrier with toner to form a toner image, and the toner image And a fixing step for fixing the toner image transferred to the surface of the transfer material, wherein the toner is the glittering toner according to <3> or <4>. An image forming method,
<8> An image holding member, a charging unit that charges the image holding member, an exposure unit that exposes the charged image holding member to form an electrostatic latent image on the surface of the image holding member, and the static with toner. A developing unit that develops the electrostatic latent image to form a toner image, a transfer unit that transfers the toner image from the image holding member to the surface of the transfer target, and a toner image transferred to the surface of the transfer target are fixed. An image forming apparatus, wherein the toner is the glitter toner according to <3> or <4>.

According to the invention described in the above <1>, the average equivalent circle diameter of the glitter pigment is not 6 to 15 μm, the number of particles having an equivalent circle diameter of 4 μm or less is not more than 20% by number, and / or the circularity is A glittering powder excellent in glitter is provided as compared with a case where particles of 0.850 or less are not 20% by number or less.
According to the invention described in <2> above, it is possible to easily produce a glitter powder having excellent glitter as compared with the case where the dispersion step, the classification step and the separation step are not repeated twice or more. A method for producing a glittering powder is provided.
According to the invention described in <3>, the average equivalent circle diameter of the glitter pigment is 6 to 15 μm, the number of particles having an equivalent circle diameter of 4 μm or less is 20% by number or less, and the circularity is 0.850 or less. As compared with the case where the particles do not contain the glittering powder having 20% by number or less, a glittering toner having excellent glitter of the obtained image is provided.
According to the invention described in <4> above, when a solid image is formed, it is possible to obtain a good color glitter image as compared with the case where the brightness of the image is less than 50 or more than 80. A bright toner is provided.
According to the invention described in <5> above, in the toner, the average equivalent circle diameter of the glitter pigment is 6 to 15 μm, particles having an equivalent circle diameter of 4 μm or less are 20% by number or less, and the circularity is 0. An electrostatic charge image developer excellent in glitter of an image obtained is provided as compared with a case where no glitter powder in which particles of .850 or less are 20% by number or less is contained.
According to the invention described in <6> above, in the toner, the average equivalent circle diameter of the glitter pigment is 6 to 15 μm, particles having an equivalent circle diameter of 4 μm or less are 20% by number or less, and the circularity is 0. Provided is a toner cartridge that contains glitter toner that is excellent in glitter of the resulting image as compared with the case where no glitter powder in which particles of .850 or less are 20% by number or less is contained.
According to the invention described in <7>, in the toner, the average equivalent circle diameter of the glitter pigment is 6 to 15 μm, particles having an equivalent circle diameter of 4 μm or less are 20% by number or less, and the circularity is 0. An image forming method is provided that is excellent in the glitter of an image obtained as compared with the case where no glitter powder in which particles of .850 or less are 20% by number or less is contained.
According to the invention described in <8> above, in the toner, the average equivalent circle diameter of the glitter pigment is 6 to 15 μm, particles having an equivalent circle diameter of 4 μm or less are 20% by number or less, and the circularity is 0. An image forming apparatus excellent in glitter of an image obtained is provided as compared with a case where no glitter powder in which particles of .850 or less are 20% by number or less is contained.

FIG. 4 is a plan view and a side view schematically showing an example of the electrostatic image developing toner of the present embodiment. FIG. 2 is a cross-sectional view schematically illustrating an example of an electrostatic charge image developing toner according to an 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 of this embodiment.

Hereinafter, the present embodiment will be described.
In the present embodiment, the description “A to B” represents not only a range between A and B but also a range including A and B at both ends thereof. For example, if “A to B” is a numerical value range, “A or more and B or less” or “B or more and A or less” is represented.

(Glitter powder)
The glittering powder of the present embodiment has an average equivalent circle diameter of 6 to 15 μm, the number of particles having an equivalent circle diameter of 4 μm or less is 20% by number or less, and the average circularity is 0.900 to 0.980. And a bright pigment having a number of particles having a circularity of 0.850 or less and 20% by number or less.
The glitter powder of this embodiment is suitably used for glitter toner.
In addition, “brightness” in the present embodiment represents having a brightness such as metallic luster. For example, when glittering powder is used for the toner described later, it has a brightness such as metallic luster when an image formed with the toner is visually recognized.

As a result of detailed studies by the present inventors, the toner image formed from the toner containing the glitter powder is greatly influenced by the absorption and scattering at the edge of the glitter powder. And that the conventional glittering powder used as the glittering pigment contains a large amount of fine powder and irregular shaped particles.
As a result of intensive studies, the present inventors have found that the average equivalent circle diameter is 6 to 15 μm, the number of particles having an equivalent circle diameter of 4 μm or less is 20% by number or less, and the average circularity is 0.900 to 0.980. The present invention has been found to be excellent in glitter of an image obtained by using a glitter powder containing a glitter pigment having a circularity of 0.850 or less and the number of particles being 20% by number or less. It came to be completed.

The glittering powder of this embodiment contains a glittering pigment in which particles having an equivalent circle diameter of 4 μm or less are 20% by number or less.
The equivalent circle diameter is the diameter of the circle when assuming a circle having the same projected area as the projected area of the particles.
In the glittering powder of the present embodiment, particles having an equivalent circle diameter of 4 μm or less contained in the glittering pigment are preferably 18% by number or less, more preferably 15% by number or less, and 12% by number. More preferably, it is as follows.

The glittering powder of this embodiment contains a glittering pigment having 20% by number or less of particles having a circularity of 0.850 or less and an average circularity of 0.900 to 0.980.
The circularity is a value calculated by the following equation.
Circularity = circle equivalent diameter perimeter / perimeter = [2 × (Aπ) ^1/2 ] / PM
(In the above formula, A represents the projected area and PM represents the perimeter.)
The closer the degree of circularity is to 1, the closer the shape of the particle is to a true sphere.
In the glitter pigment in the glitter powder of the present embodiment, particles having a circularity of 0.850 or less are preferably 18% by number or less, more preferably 15% by number or less, and more preferably 12 particles. % Or less is more preferable.
The glitter pigment in the glitter powder of this embodiment preferably has an average circularity of 0.920 to 0.980, more preferably 0.930 to 0.980, and 0.940 to 0. More preferably, 980.

In this embodiment, the equivalent circle diameter and the circularity are measured with a FPIA-3000 manufactured by Sysmex. This system employs a method in which particles dispersed in water or the like are measured by a flow-type image analysis method, and the aspirated particle suspension is guided to a flat sheath flow cell and converted into a flat sample flow by the sheath liquid. It is formed. By irradiating the sample stream with stroboscopic light, the passing particles were captured as a still image by the CCD camera through the objective lens. The captured particle image was subjected to two-dimensional image processing, and the equivalent circle diameter and circularity were calculated from the projected area and the perimeter. The equivalent circle diameter was calculated as the equivalent circle diameter from the area of the two-dimensional image with respect to each photographed particle.
In addition, HPF mode (high resolution mode) was used for the measurement, and the dilution factor was 1.0. In the data analysis, the number particle size analysis range was set to 0.50 to 200 μm, and the circularity analysis range was selected to be 0.20 to 1.00.

The bright pigment contained in the bright powder of the present embodiment has an average equivalent circle diameter of 6 to 15 μm, preferably 6 to 12 μm, more preferably 6 to 10 μm, and more preferably 6 to 8 μm. More preferably it is. It is excellent in the brightness of the image obtained as it is the said range, and is excellent in image quality.
For measuring the average particle diameter of the glitter pigment, FPIA-3000 manufactured by Sysmex is used.

The particle shape of the glittering powder of the present embodiment is preferably a particle having an average equivalent circular diameter of the particle longer than the average maximum thickness of the particle.
The ratio (C ′ / D ′) between the average maximum thickness C ′ and the average equivalent circle diameter D ′ of the glittering powder of the present embodiment is preferably 0.001 or more and 0.500 or less. It is more preferably 01 or more and 0.500 or less, and further preferably 0.05 or more and 0.100 or less. Within the above range, the glitter is excellent.
The average maximum thickness C ′ and the average equivalent circle diameter D ′ are measured by the following methods.
Place the glittering powder on a smooth surface and apply vibration to disperse it so that there is no unevenness. 1,000 bright powders are enlarged by 1,000 times with a color laser microscope “VK-9700” (manufactured by Keyence Corporation), and the maximum thickness C ′ is equivalent to the circle of the surface viewed from above. The diameter D ′ is measured and calculated by calculating the arithmetic average value thereof.
Moreover, it is preferable that the particle shape of the glitter powder of this embodiment is a flat shape.

Examples of the glitter powder include metal powder and pearl pigment.
Examples of the glitter powder include metal powders such as aluminum, brass, bronze, nickel, stainless steel, zinc, copper, silver, gold, and platinum, mica coated with titanium oxide and yellow iron oxide, barium sulfate, and layered silicic acid. Coated flaky inorganic crystal substrate such as salt, layered aluminum silicate, single crystal plate-like titanium oxide, basic carbonate, bismuth oxyoxychloride, natural guanine, flaky glass powder, flaky glass powder with metal deposition There is no particular limitation as long as it has glitter. Among these, from the viewpoints of cost, stability, availability, and glitter, metal powder is preferable, aluminum powder is more preferable, and metal powder of aluminum metal alone is particularly preferable.

(Production method of glittering powder)
The method for producing the glittering powder of the present embodiment is not particularly limited, but a dispersion step of dispersing the glittering pigment in the liquid, separating the pigment having a slow sedimentation rate by naturally precipitating the dispersed glittering pigment. And a separation step of separating the classified glitter pigment from the liquid, and a method of repeatedly performing the dispersion step, the classification step and the separation step twice or more.

It is preferable that the manufacturing method of the glitter powder of this embodiment includes a dispersion step of dispersing the glitter pigment in the liquid.
The liquid used in the dispersion step is preferably a liquid at 25 ° C., more preferably a liquid selected from the group consisting of silicone oil, mineral oil, liquid paraffin, vegetable oil, and animal oil, silicone oil, A liquid selected from the group consisting of mineral oil and liquid paraffin is more preferable, and a liquid selected from the group consisting of silicone oil and mineral oil is particularly preferable. As mineral oil, mineral spirit can be preferably exemplified.
There is no restriction | limiting in particular as a dispersion method, A well-known dispersion method and a well-known dispersion | distribution apparatus can be used.
The mixing ratio of the glitter pigment and the liquid may be appropriately selected as desired, but the weight ratio is preferably the glitter pigment: liquid = 0.01 to 10: 100, and the glitter pigment: liquid = More preferably, it is 0.1-5: 100.

It is preferable that the method for producing the glittering powder of the present embodiment includes a classification step of spontaneously precipitating the dispersed glittering pigment and separating and classifying the pigment having a slow sedimentation rate.
In the classification step, classification is performed by natural sedimentation. Bright pigments have few spherical particles, many have various shapes, and many particles have a large change in projected area depending on the direction, so they are classified in a stationary state with little flow by natural sedimentation, and multiple times. It is preferable to repeat the classification.
The size and shape of the classification container are not particularly limited, and a container having a desired size and shape may be used.
The classification time is not particularly limited, and may be appropriately selected depending on the progress of natural sedimentation and classification.
In the classification step, it is preferable to classify by collecting the settled glitter pigment and / or by removing the glitter pigment that has not settled or is being settled.

It is preferable that the manufacturing method of the glitter powder of this embodiment includes a separation step of separating the classified glitter pigment from the liquid.
There is no restriction | limiting in particular as a separation method, Well-known separation methods, such as filtration and centrifugation, can be used.
Further, after the separation step, the obtained bright pigment may optionally be subjected to a known step such as washing or drying.

  It is preferable that the manufacturing method of the glittering powder of this embodiment includes the method of repeating the said dispersion | distribution process, a classification process, and a separation process twice or more. As mentioned above, glitter pigments have few spherical particles, many have various shapes, and there are many particles whose projected area varies greatly depending on the direction. In order to remove, it is preferable to repeat several times.

(Brightness toner)
The glitter toner of this embodiment (hereinafter also simply referred to as “toner”) contains the glitter pigment of this embodiment and a binder resin.
The content of the glitter powder in the glitter toner of the present embodiment is preferably 1 part by weight or more and 70 parts by weight or less, and more preferably 5 parts by weight or more and 50 parts by weight or less with respect to 100 parts by weight of the total weight of the toner. preferable.

<Binder resin>
The toner according to the exemplary embodiment includes a binder resin.
Examples of the binder resin include polycondensation resins and addition polymerization resins. For example, polyolefin resins such as polyethylene and polypropylene, styrene resins mainly composed of polystyrene, poly (α-methylstyrene), and polymethyl. Examples include (meth) acrylic resins, styrene- (meth) acrylic copolymer resins, polyamide resins, polycarbonate resins, polyether resins, polyester resins, and copolymer resins mainly composed of methacrylate, polyacrylonitrile, and the like. .
Among these, a polyester resin is preferable as the binder resin. Since the polyester resin is hydrophilic, it is well dispersed during toner formation, and the europium colorant is taken into the toner base particles in a more uniform state.

As the polycondensation resin, for example, a polyester resin and a polyamide resin can be preferably exemplified, but in particular, a polyester resin obtained using a polycondensable monomer containing a polycarboxylic acid and a polyol. Preferably there is.
Examples of the polycondensable monomer that can be used in this embodiment include polycarboxylic acids, polyols, hydroxycarboxylic acids, polyamines, and mixtures thereof. In particular, the polycondensable monomer is preferably a polyvalent carboxylic acid, a polyol, and further an ester compound (oligomer and / or prepolymer) thereof. After undergoing a direct ester reaction or transesterification reaction, a polyester is obtained. What obtains resin is good.
In the present embodiment, the polycondensation resin is obtained by polycondensation of at least one selected from the group consisting of polycondensable monomers, oligomers thereof and prepolymers. Is preferably used.

The polyvalent carboxylic acid is a compound containing two or more carboxyl groups in one molecule. Among these, dicarboxylic acid is a compound containing two carboxyl groups in one molecule. For example, oxalic acid, succinic acid, glutaric acid, maleic acid, adipic acid, β-methyladipic acid, azelaic acid, sebacic acid, Nonanedicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, fumaric acid, citraconic acid, diglycolic acid, cyclohexane-3,5-diene-1,2-carboxylic acid, hexahydroterephthalic acid, malonic acid, pimeline Acid, peric acid, phthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-carboxyphenylacetic acid, p-phenylenediacetic acid, m-phenylenediacetic acid, o-phenylenediacetic acid, diphenyl Acetic acid, diphenyl-p, p'-dicarboxylic acid, naphth Ren-1,4-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, anthracene dicarboxylic acid, and cyclohexane dicarboxylic acid.
Examples of the polycarboxylic acid other than dicarboxylic acid include trimellitic acid, trimesic acid, pyromellitic acid, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, pyrenetricarboxylic acid, pyrenetetracarboxylic acid, itaconic acid, glutaconic acid, Examples thereof include n-dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid, isododecenyl succinic acid, n-octyl succinic acid, n-octenyl succinic acid, and the like, and lower esters thereof. Furthermore, acid halides and acid anhydrides are not limited to this.
These may be used individually by 1 type and may use 2 or more types together.
In addition, a lower ester shows that the carbon number of the alkoxy part of ester is 1-8. Specific examples include methyl ester, ethyl ester, n-propyl ester, isopropyl ester, n-butyl ester, and isobutyl ester.

A polyol is a compound containing two or more hydroxyl groups in one molecule. Among these, diol is a compound containing two hydroxyl groups in one molecule. Specifically, for example, as diol, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,14-eicosandecanediol, diethylene glycol, triethylene glycol , Dipropylene glycol, polyester Lenglycol, polypropylene glycol, polytetramethylene ether glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,4-butenediol, neopentyl glycol, 1,4-cyclohexanediol, polytetramethylene glycol, Examples include hydrogenated bisphenol A, bisphenol A, bisphenol F, bisphenol S, and alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adducts of the above bisphenols. Among these, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is combined use with.
Moreover, in order to make water dispersibility easy, a 2, 2- dimethylol propionic acid, a 2, 2- dimethylol butanoic acid, a 2, 2- dimethylol valeric acid etc. are illustrated, for example.

Examples of trihydric or higher alcohols include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, hexamethylolmelamine, hexaethylolmelamine, tetramethylolbenzoguanamine, tetraethylolbenzoguanamine, sorbitol, trisphenol PA, phenol novolac, Examples thereof include cresol novolac, and alkylene oxide adducts of the above trivalent or higher polyphenols. These may be used individually by 1 type and may use 2 or more types together.
In addition, an amorphous resin or a crystalline resin can be easily obtained by combining these polycondensable monomers.

  Hydroxycarboxylic acid can also be used. Specific examples of the hydroxycarboxylic acid include hydroxyheptanoic acid, hydroxyoctanoic acid, hydroxydecanoic acid, hydroxyundecanoic acid, malic acid, tartaric acid, mucoic acid, and citric acid.

  Polyamines include ethylenediamine, diethylenediamine, 1,2-propanediamine, 1,3-propanediamine, 1,4-butanediamine, 1,4-butenediamine, 2,2-dimethyl-1,3-butane. Examples include diamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,4-cyclohexanediamine, 1,4-cyclohexanebis (methylamine), and the like.

  The weight average molecular weight of the polycondensation resin obtained by polycondensation of the polycondensable monomer is preferably 1,500 or more and 40,000 or less, and preferably 3,000 or more and 30,000 or less. More preferred. When the weight average molecular weight is 1,500 or more, the cohesive force of the binder resin is good and the hot offset property is excellent, and when it is 40,000 or less, the hot offset property is excellent and the minimum fixing temperature is excellent. This is preferable. Further, it may be partially branched or cross-linked by selecting the carboxylic acid valence or alcohol valence of the monomer.

Moreover, it is preferable that the acid value of the polyester resin obtained is 1 mg * KOH / g or more and 50 mg * KOH / g or less. The first reason is that control of the particle size and distribution of the toner in the aqueous medium is indispensable for practical use as a high-quality toner, and the acid value is 1 mg · KOH / g or more. In the granulation step, sufficient particle size and distribution can be achieved, and when used in toner, sufficient chargeability can be obtained. Further, when the acid value of the polyester to be polycondensed is 50 mg · KOH / g or less, a sufficient molecular weight can be obtained for obtaining image quality strength as a toner during polycondensation, and the chargeability of the toner under high humidity Is less dependent on the environment and has excellent image reliability.
Although there is no restriction | limiting in particular as a measuring method of an acid value, It is preferable to measure according to JISK0070.

When an amorphous polyester resin is used, the glass transition temperature Tg of the amorphous polyester resin is preferably 50 to 80 ° C, and more preferably 50 to 65 ° C. When the Tg is 50 ° C. or more, the cohesive force of the binder resin itself in a high temperature range is good, and thus the hot offset property is excellent at the time of fixing. Further, when Tg is 80 ° C. or less, sufficient melting is obtained and the minimum fixing temperature is hardly increased.
The glass transition temperature of the binder resin refers to a value measured by a method (DSC method) defined in ASTM D3418-82.

Examples of the addition polymerizable monomer used for the preparation of the addition polymerization type resin include a cationic polymerizable monomer and a radical polymerizable monomer, and a radical polymerizable monomer is preferable.
As radically polymerizable monomers, styrenic monomers, unsaturated carboxylic acids, (meth) acrylates ("(meth) acrylate" means acrylate and methacrylate, and so on. N-vinyl compounds, vinyl esters, halogenated vinyl compounds, N-substituted unsaturated amides, conjugated dienes, polyfunctional vinyl compounds, polyfunctional (meth) acrylates, and the like. . Among these, N-substituted unsaturated amides, conjugated dienes, polyfunctional vinyl compounds, polyfunctional (meth) acrylates, and the like may cause a crosslinking reaction in the produced polymer. it can. These can be used alone or in combination.

Examples of the addition polymerizable monomer that can be used in this embodiment include a radical polymerizable monomer, a cationic polymerizable monomer, or an anion polymerizable monomer. Preferably there is.
The radically polymerizable monomer is preferably a compound having an ethylenically unsaturated bond, and has an aromatic ethylenically unsaturated compound (hereinafter also referred to as “vinyl aromatic”) or an ethylenically unsaturated bond. Carboxylic acids (unsaturated carboxylic acids), derivatives of unsaturated carboxylic acids such as esters, aldehydes, nitriles or amides, N-vinyl compounds, vinyl esters, halogenated vinyl compounds, N-substituted unsaturated amides, conjugated dienes, many It is more preferably a functional vinyl compound or a polyfunctional (meth) acrylate.

  Specifically, for example, unsubstituted vinyl aromatics such as styrene and p-vinylpyridine, α-substituted styrene such as α-methylstyrene and α-ethylstyrene, m-methylstyrene, p-methylstyrene, 2, Aromatic nucleus substituted styrene such as 5-dimethylstyrene, vinyl aromatics such as aromatic nucleus halogen substituted styrene such as p-chlorostyrene, p-bromostyrene, dibromostyrene, (meth) acrylic acid (in addition, “(meth) acrylic” "Means acrylic and methacrylic, and the same shall apply hereinafter.), Unsaturated carboxylic acids such as crotonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, methyl (meth) acrylate, ethyl ( (Meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate Unsaturated carboxylic acid esters such as hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycidyl (meth) acrylate, benzyl (meth) acrylate, (meth) acrylaldehyde, (meth) acrylonitrile, (meth) acrylamide, etc. Unsaturated carboxylic acid derivatives, N-vinyl compounds such as N-vinyl pyridine and N-vinyl pyrrolidone, vinyl esters such as vinyl formate, vinyl acetate and vinyl propionate, vinyl chloride, vinyl bromide, vinylidene chloride, etc. Halogenated vinyl compounds, N-methylol acrylamide, N-ethylol acrylamide, N-propanol acrylamide, N-methylol maleamic acid, N-methylol maleamic acid ester, N-methylol maleimide, N-ethylo N-substituted unsaturated amides such as lumaleimide, conjugated dienes such as butadiene and isoprene, polyfunctional vinyl compounds such as divinylbenzene, divinylnaphthalene and divinylcyclohexane, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate , Propylene glycol di (meth) acrylate, tetramethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, hexamethylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri ( (Meth) acrylate, glycerol di (meth) acrylate, glycerol tri (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythrito Tritri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol di (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, Examples include polyfunctional acrylates such as dipentaerythritol hexa (meth) acrylate, sorbitol tri (meth) acrylate, sorbitol tetra (meth) acrylate, sorbitol penta (meth) acrylate, and sorbitol hexa (meth) acrylate. Moreover, the sulfonic acid and phosphonic acid which have an ethylenically unsaturated bond, and those derivatives can also be used. Among these, N-substituted unsaturated amides, conjugated dienes, polyfunctional vinyl compounds, polyfunctional acrylates, and the like can also cause a crosslinking reaction in the produced polymer. These addition polymerizable monomers may be used alone or in combination of two or more.

  Further, the content of the binder resin in the toner of the exemplary embodiment is preferably 10 to 90% by weight, more preferably 30 to 85% by weight, and more preferably 50 to 80% by weight with respect to the total weight of the toner. % Is more preferable.

<Release agent>
The toner of the exemplary embodiment preferably contains a release agent.
Specific examples of the release agent include, for example, ester wax, polyethylene, polypropylene, or a copolymer of polyethylene and polypropylene, but polyglycerin wax, microcrystalline wax, paraffin wax, carnauba wax, sazol wax, and montanic acid ester. Wax, deacidified carnauba wax, palmitic acid, stearic acid, montanic acid, blandic acid, eleostearic acid, valinalic acid and other unsaturated fatty acids, stearyl alcohol, aralkyl alcohol, bephenyl alcohol, carnauvyl alcohol, ceryl alcohol , Saturated alcohols such as long chain alkyl alcohols having a long chain alkyl group; polyhydric alcohols such as sorbitol; linoleic acid amides Fatty acid amides such as oleic acid amide and lauric acid amide; saturated fatty acid bisamides such as methylene bis stearic acid amide, ethylene bis capric acid amide, ethylene bis lauric acid amide, hexamethylene bis stearic acid amide, ethylene bis oleic acid amide, Unsaturated fatty acid amides such as hexamethylene bisoleic acid amide, N, N′-dioleyl adipic acid amide, N, N′-dioleyl sebacic acid amide; m-xylene bisstearic acid amide, N, N′— Aromatic bisamides such as distearyl isophthalic acid amide; fatty acid metal salts such as calcium stearate, calcium laurate, zinc stearate, magnesium stearate (generally called metal soap); aliphatic hydrocarbon wax and styrene Waxes grafted with vinyl monomers such as acrylic acid; Partially esterified products of fatty acids such as behenic acid monoglyceride and polyhydric alcohols; Methyl ester compounds having hydroxyl groups obtained by hydrogenation of vegetable oils, etc. Is mentioned.

The said mold release agent may be used individually by 1 type, or may use 2 or more types together.
The content of the release agent is preferably 1 to 20% by weight and more preferably 3 to 15% by weight with respect to 100% by weight of the binder resin. Within the above range, both good fixing and image quality characteristics can be achieved.

<Other colorants>
The toner of the exemplary embodiment may contain a colorant other than the glittering powder of the exemplary embodiment, if necessary.
As the other colorant, a known colorant can be used, and it may be arbitrarily selected from the viewpoints of hue angle, saturation, brightness, weather resistance, OHP permeability, and dispersibility in the toner.
Specifically, various pigments such as watch young red, permanent red, brilliantamine 3B, brilliantamine 6B, dapon oil red, pyrazolone red, resol red, rhodamine B lake, lake red C rose bengal, and acridine series , Xanthene, azo, benzoquinone, azine, anthraquinone, thioindico, dioxazine, thiazine, azomethine, indico, thioindico, phthalocyanine, aniline black, polymethine, triphenylmethane, diphenylmethane Examples thereof include various colorants such as those based on thiazine, thiazine, thiazole and xanthene.

  Other colorants include, for example, carbon black, nigrosine dye (CI No. 50415B), aniline blue (CI No. 50405), calco oil blue (CI No. azoic Blue 3), chrome yellow ( CINo.14090), Ultramarine Blue (CINo.77103), DuPont Oil Red (CINo.26105), Quinoline Yellow (CINo.47005), Methylene Blue Chloride (CINo.52015), Phthalocyanine Blue (CINo. 74160), malachite green oxalate (CI No. 42000), lamp black (CI No. 77266), rose bengal (CI No. 45435), and mixtures thereof can be preferably used.

The amount of other colorant used is preferably 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the toner. Moreover, as a coloring agent, these pigments, dyes, etc. can be used individually by 1 type, or 2 or more types can be used together.
As a method for dispersing the other colorant, any method, for example, a general dispersion method such as a rotary shear type homogenizer, a ball mill having a medium, a sand mill, or a dyno mill can be used, and is not limited at all. . These colorant particles may be added to the mixed solvent at the same time as other particle components, or may be divided and added in multiple stages.

<External additive>
The toner of this embodiment may contain an external additive.
Examples of the external additive include inorganic particles and organic particles, and inorganic particles are preferable.
Examples of inorganic particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, cerium chloride, Examples include Bengala, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, zirconium oxide, silicon carbide, and silicon nitride.
Among these, from the viewpoint of transferability and glitter of the resulting image, it is preferable that silica particles are included as the external additive, and it is particularly preferable that the external additive is silica particles.
The silica particles are preferably vapor phase silica.

It is preferable that the surface of the inorganic particles is previously hydrophobized. This hydrophobization treatment is more effective for improving the powder fluidity of the toner, as well as the environmental dependency of charging and the resistance to carrier contamination.
The hydrophobizing treatment may be performed by immersing the inorganic particles in a hydrophobizing agent. Although there is no restriction | limiting in particular as said hydrophobic treatment agent, For example, a silane coupling agent, a silicone oil, a titanate coupling agent, an aluminum coupling agent etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, silane coupling agents are preferable.

  Organic particles are generally used for the purpose of improving cleaning properties and transfer properties. Specifically, for example, fluorine resin powders such as polyvinylidene fluoride and polytetrafluoroethylene, fatty acid metal salts such as zinc stearate and calcium stearate. , Polystyrene, polymethyl methacrylate and the like.

The number average primary particle size of the external additive is preferably 5 to 300 nm, and more preferably 10 to 200 nm.
Moreover, an external additive may be used individually by 1 type, or may use 2 or more types together.
The content of the external additive is preferably in the range of 0.01 to 5 parts by weight and more preferably in the range of 0.1 to 3.0 parts by weight with respect to the total weight of the toner.

<Other ingredients>
In addition to the above components, various components such as an internal additive, a charge control agent, inorganic powder (inorganic particles), and organic particles may be added to the toner as necessary.
Examples of the internal additive include metals such as ferrite, magnetite, reduced iron, cobalt, nickel, and manganese, alloys, and magnetic materials such as compounds containing these metals. When the magnetic material is used as a magnetic toner, the ferromagnetic particles preferably have an average particle size of 2 μm or less, more preferably about 0.1 to 0.5 μm. The amount contained in the toner is preferably 20 to 200 parts by weight with respect to 100 parts by weight of the resin component, and particularly preferably 40 to 150 parts by weight with respect to 100 parts by weight of the resin component. Further, it is preferable that the magnetic characteristics at the application of 10K oersted are those having a coercive force (Hc) of 20 to 300 oersted, saturation magnetization (σs) of 50 to 200 emu / g, and residual magnetization (σr) of 2 to 20 emu / g.

  Examples of the charge control agent include fluorine surfactants, salicylic acid metal complexes, metal-containing dyes such as azo metal compounds, polymer acids such as polymers containing maleic acid as a monomer component, and quaternary ammonium salts. And azine dyes such as nigrosine.

  The toner may contain an inorganic powder for the purpose of adjusting viscoelasticity. Examples of inorganic powders include silica, alumina, titania, calcium carbonate, magnesium carbonate, calcium phosphate, and cerium oxide. Can be mentioned.

<Aspect and physical properties of toner>
The volume average particle diameter (D _50v ) of the toner of the exemplary embodiment is preferably 5 μm or more and 40 μm or less, more preferably 8 μm or more and 40 μm or less, and further preferably 10 μm or more and 20 μm or less. Within the above range, the occurrence of fog is small, and the particles are destroyed during cleaning, and the image carrier is prevented from being damaged.
The toner preferably has a narrow particle size distribution, and more specifically, the ratio of the 16% diameter (D _16p ) and the 84% diameter (D _84p ) in _terms of the square root in terms of the smaller number particle size of the toner. (GSDp), that is, GSDp represented by the following formula is preferably 1.40 or less, more preferably 1.31 or less, and particularly preferably 1.27 or less. Moreover, it is preferable that GSDp is 1.15 or more.
_{GSDp = {(D 84p) /} (D 16p)} 0.5
If the volume average particle size and GSDp are both in the above ranges, extremely small particles do not exist, and therefore, it is possible to suppress a decrease in developability due to an excessive charge amount of the small particle size toner.

A Coulter Multisizer II (manufactured by Beckman-Coulter) can be used for measuring the average particle diameter of particles such as toner. In this case, measurement can be performed using an optimum aperture depending on the particle size level of the particles. The particle diameter of the measured particle is expressed by a volume average particle diameter.
When the particle size is about 5 μm or less, the particle size can be measured using a laser diffraction / scattering particle size distribution measuring device (LA-700, manufactured by Horiba, Ltd.).
Furthermore, when the particle size is on the order of nanometers, it can be measured using a BET specific surface area measuring device (Flow Sorb II 2300, manufactured by Shimadzu Corporation).

In this embodiment, the toner shape factor SF1 is preferably in the range of 110 to 160, and more preferably in the range of 120 to 150. Within the above range, transfer unevenness in a high temperature and high humidity environment is further suppressed.
The shape factor SF1 is a shape factor indicating the degree of unevenness on the particle surface, and is calculated by the following equation.

In the formula, ML indicates the maximum length of the particle, and A indicates the projected area of the particle.
As a specific measurement method of SF1, for example, first, an optical microscope image of toner spread on a slide glass is taken into an image analysis device through a video camera, SF1 is calculated for 50 toners, and an average value is obtained. Is mentioned.

The glitter toner according to the present embodiment has a light receiving angle of + 30 ° measured when a solid image of toner is formed and irradiated with incident light having an incident angle of −45 ° by a goniophotometer. The ratio (A / B) between the reflectance A and the reflectance B at a light receiving angle of −30 ° is preferably 2 or more and 100 or less. It is excellent in the brightness of the image obtained as it is the said range.
The ratio (A / B) is preferably 20 or more and 100 or less, more preferably 40 or more and 100 or less, still more preferably 50 or more and 100 or less, and particularly preferably 60 or more and 90 or less. preferable.

Measurement of the ratio (A / B) with a goniophotometer First, the incident angle and the light receiving angle will be described. 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 (A / B) will be described.
In this embodiment, when measuring the ratio (A / B), a “solid image” is first formed by the following method. The developer used as a sample is filled in a developer of DocuCentre-III C7600 manufactured by Fuji Xerox Co., Ltd., and is fixed on recording paper (OK topcoat + paper, manufactured by Oji Paper Co., Ltd.) at a fixing temperature of 190 ° C. and fixing pressure. A solid image having a toner loading of 4.5 g / cm ² is formed at 4.0 kg / cm ² . The “solid image” refers to an image with a printing rate of 100%.
Using a spectroscopic color difference color difference meter GC5000L manufactured by Nippon Denshoku Industries Co., Ltd. as a variable angle photometer, incident light with an incident angle of −45 ° is incident on the solid image. The reflectance A at the light receiving angle + 30 ° and the reflectance B at the light receiving angle −30 ° are measured. Note that the reflectance A and the reflectance B were measured at intervals of 20 nm for light having a wavelength in the range of 400 to 700 nm, and the average value of the reflectance at each wavelength was used. The ratio (A / B) is calculated from these measurement results.

The glitter toner of this embodiment preferably has an average equivalent circle diameter D of the toner that is longer than the average maximum thickness C of the toner.
The equivalent circle diameter M is given by the following equation, where X is the projected area on the flat surface where the projected area is the maximum surface.
M = (X / π) ^1/2
The toner shown in FIG. 1 is a flat toner having a circle-equivalent diameter M longer than the maximum thickness L.
In the glitter toner of this embodiment, the ratio (C / D) of the average maximum thickness C of the toner to the average equivalent circle diameter D of the toner is preferably 0.001 or more and 0.500 or less. It is more preferably 01 or more and 0.500 or less, and further preferably 0.05 or more and 0.100 or less. It is excellent in the brightness of the image obtained as it is the said range.

The average maximum thickness C and the average equivalent circle diameter D are measured by the following methods.
The toner is placed on a smooth surface, and is vibrated and dispersed so that there is no unevenness. 1,000 toners were enlarged 1,000 times with a color laser microscope “VK-9700” (manufactured by Keyence Corporation), and the maximum thickness C and the equivalent circle diameter D of the surface viewed from above were measured. And it calculates by calculating | requiring those arithmetic mean values.
Similarly, the average major axis length and the average minor axis length were increased by 1,000 times with a color laser microscope (VK-9700) (manufactured by Keyence Corporation) for 1,000 toners. The length and the short axis length are measured, and the arithmetic average value thereof is calculated.

In the present embodiment, the average maximum thickness C is preferably 1 to 6 μm, and more preferably 2 to 5 μm.
The average equivalent circle diameter D is preferably 5 to 40 μm, more preferably 8 to 30 μm, and still more preferably 10 to 25 μm.
It is preferable that the average maximum thickness C and the average equivalent circle diameter D are within the above ranges because excellent glitter can be obtained.

Further, in the glitter toner of the present embodiment, when the cross section in the thickness direction of the toner is observed, the angle between the major axis direction of the toner and the major axis direction of the glitter pigment is −30 ° to The number of glitter pigments in the range of + 30 ° is preferably 60% by number or more of all observed glitter pigments.
The toner T shown in FIGS. 1 and 2 is a flat toner having an equivalent circle diameter longer than the thickness L, and contains scale-like pigment particles MP.
As shown in FIG. 2, when the toner T has a flat shape having a circle-equivalent diameter longer than the thickness L, the toner moves to an image carrier, an intermediate transfer member, a recording medium, etc. in the image forming development process and transfer process. At this time, since the toner tends to move so as to cancel the charge to the maximum, it is considered that the toners are arranged so that the area to be adhered becomes the maximum. In other words, on the recording medium to which the toner is finally transferred, it is considered that the flat toner is arranged so that the flat surface side faces the recording medium surface. Also in the fixing process of image formation, it is considered that the flat toners are arranged so that the flat surface side faces the recording medium surface due to the pressure during fixing. In particular, it is considered that the external addition of the fluororesin particles further facilitates the alignment of the toner so that the adhesion area is maximized as described above.
Therefore, among the scale-like pigment particles contained in the toner, “the angle between the major axis direction in the cross section of the toner and the major axis direction of the pigment particles is in the range of −30 ° to + 30 °. It is considered that the pigment particles satisfying the requirement "" are arranged so that the surface side having the largest area faces the recording medium surface. When the image thus formed is irradiated with light, the ratio of the pigment particles that diffusely reflect the incident light is suppressed, so that the above range (A / B) can be achieved. .

As described above, when the cross section in the thickness direction of the toner is observed, the pigment particles in which the angle between the major axis direction of the toner and the major axis direction of the pigment particles is in the range of −30 ° to + 30 °. Is preferably 60% by number or more of all the observed pigment particles. Furthermore, the number is more preferably 70% by number to 95% by number, and particularly preferably 80% by number to 90% by number.
When the number is 60% by number or more, excellent glitter is easily obtained.

Here, a method for observing the cross section of the toner will be described.
After embedding the toner 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 (in this embodiment, LEICA ultramicrotome (manufactured by Hitachi High-Technologies Corporation)), and the observation sample is prepared. Make it. The cross section of the toner particles is observed with a transmission electron microscope (TEM) at a magnification of about 5,000 times. For the 1,000 toners observed, the number of pigment particles in which the angle between the major axis direction of the toner cross section and the major axis direction of the pigment particles is in the range of −30 ° to + 30 ° is calculated using image analysis software. And calculate the ratio.

  The “major axis direction in the cross section of the toner” means a direction perpendicular to the thickness direction of the toner having an average equivalent circle diameter D longer than the above average maximum thickness C, and “major axis direction of pigment particles”. "Represents the length direction of the pigment particles.

<Method for producing glitter toner>
The toner of the exemplary embodiment is manufactured by a known method such as a wet method or a dry method, but is preferably manufactured by a wet method. Examples of the wet method include a melt suspension method, an emulsion aggregation method, a dissolution suspension method, and the like, and among these, it is particularly preferable to produce by an emulsion aggregation method.
Here, the emulsion aggregation method is a method of preparing dispersions (emulsion, glitter pigment dispersion, etc.) each containing components (binder resin, colorant, etc.) contained in the toner, and mixing these dispersions. And then agglomerated particles above the melting temperature or glass transition temperature of the binder resin (in the case of producing a toner containing both a crystalline resin and an amorphous resin, In addition, the toner components are aggregated and united by heating to a glass transition temperature or higher) of the amorphous resin.

If the toner is produced by an emulsion aggregation method, it is preferable to prepare the toner by the following production method, for example.
First, glitter pigment particles are prepared, and the glitter pigment particles and the binder resin are dispersed and dissolved in a solvent and mixed. By dispersing this in water by phase inversion emulsification or shear emulsification, glitter pigment particles coated with a resin are formed. Other compositions (for example, a release agent, a shell resin, etc.) are added here, a flocculant is further added, the temperature is raised to near the glass transition temperature (Tg) of the resin while stirring, and the agglomerated particles are dispersed. Form. In this step, for example, by using a stirring blade that forms a laminar flow having two paddles and stirring at a high stirring speed (for example, 500 rpm or more and 1,500 rpm or less), the glitter pigment particles are aggregated particles. Among them, the major axis direction is aligned, and the agglomerated particles also aggregate in the major axis direction, so that the toner thickness becomes smaller (that is, the average equivalent circle diameter D of the toner than the average maximum thickness C of the toner). Long toner can be easily obtained.) Finally, it is made alkaline for particle stabilization, and then the temperature is raised to a temperature equal to or higher than the glass transition temperature (Tg) of the toner, preferably near Tg + 20 ° C., and the aggregated particles are coalesced. In this coalescence process, coalescence is performed at a lower temperature (for example, 60 ° C. or more and 80 ° C. or less), so that the movement accompanying the rearrangement of the material is reduced, the orientation of the pigment is maintained, and the thickness direction of the toner When observing the cross section, the number of glitter pigments in which the angle between the major axis direction of the toner and the major axis direction of the metal pigment is in the range of −30 ° to + 30 ° is the total glitter property observed. A toner having 60% by number or more of pigments can be easily obtained.

  In addition, as said stirring speed, 650 rpm or more and 1,130 rpm or less are preferable, and 760 rpm or more and 870 rpm or less are especially preferable. Further, the coalescence temperature in the coalescence step is preferably 63 ° C. or more and 75 ° C. or less, and particularly preferably 65 ° C. or more and 70 ° C. or less.

  There are no particular limitations on the method of externally adding the toner base particles to the surface, and any known method can be used, for example, a mechanical method or a chemical method.

(Electrostatic image developer)
The electrostatic charge image developer of this embodiment (hereinafter sometimes referred to as “developer”) is not particularly limited as long as it contains the glittering toner of this embodiment, and the toner is used alone. A one-component developer or a two-component developer including a toner and a carrier may be used. In the case of a one-component developer, a toner containing magnetic metal particles or a non-magnetic one-component toner containing no magnetic metal particles may be used.

The carrier is not particularly limited as long as it is a known carrier, and iron powder carriers, ferrite carriers, surface-coated ferrite carriers, and the like are used. Each surface-added powder may be used after a desired surface treatment.
Specific examples of the carrier include the following resin-coated carriers. Examples of the carrier core particle include normal iron powder, ferrite, and magnetite molding, and the volume average particle size is preferably 30 to 200 μm.

  Examples of the coating resin for the resin-coated carrier include styrenes such as styrene, parachlorostyrene, and α-methylstyrene; methyl acrylate, ethyl acrylate, n-propyl acrylate, lauryl acrylate, acrylic acid 2 -Α-methylene fatty acid monocarboxylic acids such as ethylhexyl, methyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate; nitrogen-containing acrylics such as dimethylaminoethyl methacrylate; acrylonitrile, methacrylonitrile, etc. Vinyl nitriles; vinyl pyridines such as 2-vinyl pyridine and 4-vinyl pyridine; vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether; vinyl methyl ketone, vinyl ethyl ketone, vinyl isopropenyl Homopolymers such as vinyl ketones such as ketones; olefins such as ethylene and propylene; vinyl-based fluorine-containing monomers such as vinylidene fluoride, tetrafluoroethylene and hexafluoroethylene; and copolymers comprising two or more types of monomers Furthermore, silicone resins containing methyl silicone, methyl phenyl silicone, etc., polyesters containing bisphenol, glycol, etc., epoxy resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, polycarbonate resins and the like can be mentioned. These resins may be used alone or in combination of two or more. The coating amount of the coating resin is preferably in the range of about 0.1 to 10 parts by weight and more preferably in the range of 0.5 to 3.0 parts by weight with respect to 100 parts by weight of the core particles.

  For the production of the carrier, a heating type kneader, a heating type Henschel mixer, a UM mixer or the like is used. Depending on the amount of the coating resin, a heating type fluidized rolling bed, a heating type kiln or the like is used.

When a carrier in which ferrite particles are used as a core and coated with a resin in which carbon black or the like as a conductive agent and melamine beads or the like as a charge control agent are dispersed in methyl acrylate or ethyl acrylate and styrene or the like is used as a carrier, Since the resistance controllability is excellent even when the film thickness is increased, the image quality and the image quality maintenance are excellent, which is more preferable.
The mixing ratio of the toner and the carrier in the developer is not particularly limited and is selected according to the purpose.

(Image forming method)
An image forming method using the glitter toner of this embodiment will be described. The glitter toner of the present embodiment is used in an image forming method using a known electrophotographic method. Specifically, it is used in an image forming method having the following steps.
That is, a preferred image forming method includes a latent image forming step for forming an electrostatic latent image on the surface of the image carrier, and development for forming the toner image by developing the electrostatic latent image formed on the surface of the image carrier with toner. And a fixing step for fixing the toner image transferred to the surface of the transfer medium. The electrostatic charge of the present embodiment is used as the toner. Image developing toner is used. Further, the transfer step may use an intermediate transfer member that mediates transfer of the toner image from the image holding member to the transfer target.
Further, it may further include a cleaning step for removing residual toner on the surface of the image carrier after the transfer.

  In addition, the image forming method of the present embodiment is such that the obtained image has at least a layer formed of color toners such as yellow, magenta, cyan, and black on the layer formed of the glitter toner of the present embodiment. An image having a color metallic color having at least a layer formed of a color toner on an upper layer of a layer formed of the glitter toner of the present embodiment is more preferable. Since the glitter powder of this embodiment has high brightness, even when used in the lower layer of the color toner layer, the glitter is sufficiently exhibited in the image, and a good color metallic image is particularly suitably formed.

Each of the above steps is a general step per se, and is described in, for example, JP-A-56-40868 and JP-A-49-91231. Note that the image forming method of the present embodiment can be carried out by using a known image forming apparatus such as a copying machine or a facsimile machine.
The electrostatic latent image forming step is a step of forming an electrostatic latent image on an image carrier (photoconductor).
The developing step is a step of developing the electrostatic latent image with a developer layer on a developer holding member to form a toner image. The developer layer is not particularly limited as long as it contains the glitter toner of this embodiment.
The transfer step is a step of transferring the toner image onto a transfer target. Examples of the transfer medium in the transfer process include an intermediate transfer medium and a recording medium such as paper.
In the fixing step, for example, there is a method of forming a copy image by fixing the toner image transferred onto the transfer paper by a heating roller fixing device in which the temperature of the heating roller is set to a constant temperature.
The cleaning step is a step of removing the electrostatic charge image developer remaining on the image carrier.
As the transfer target, a recording medium such as an intermediate transfer member or paper can be used.
Examples of the recording medium include paper used for electrophotographic copying machines and printers, OHP sheets, etc., for example, coated paper whose surface is coated with resin, art paper for printing, and the like. Etc. can be used suitably.

  The image forming method of the present embodiment may further include a recycling step. The recycling step is a step of transferring the electrostatic image developing toner collected in the cleaning step to the developer layer. The image forming method including the recycling process is performed using an image forming apparatus such as a toner recycling system type copying machine or facsimile machine. Further, the present invention may be applied to a recycling system in which the cleaning process is omitted and toner is collected simultaneously with development.

(Image forming device)
The image forming apparatus of the present embodiment is an image forming apparatus using the glitter toner of the present embodiment. The image forming apparatus of this embodiment will be described.
The image forming apparatus according to this embodiment includes an image carrier, a charging unit that charges the image carrier, and an exposure unit that exposes the charged image carrier to form an electrostatic latent image on the surface of the image carrier. Developing means for developing the electrostatic latent image with toner to form a toner image; transfer means for transferring the toner image from the image carrier to the surface of the transfer body; and transferring the toner image to the surface of the transfer body. It is preferable that the toner is a glittering toner according to the exemplary embodiment.
The image forming apparatus according to the present exemplary embodiment is not particularly limited as long as it includes at least the image holding member, the charging unit, the exposure unit, the developing unit, the transfer unit, and the fixing unit as described above. However, other cleaning means, static elimination means, and the like may be included as necessary.
In the transfer unit, the transfer may be performed twice or more using an intermediate transfer member. Examples of the transfer medium in the transfer unit include an intermediate transfer medium and a recording medium such as paper.
The image forming apparatus according to the present embodiment is preferably an apparatus that includes other color toners such as yellow, magenta, cyan, and black in addition to the glitter toner according to the present embodiment.

The image carrier and each of the above-described units can preferably use the configurations described in the respective steps of the image forming method. As each of the above-described means, a known means in the image forming apparatus can be used. In addition, the image forming apparatus according to the present embodiment may include means and devices other than the above-described configuration. Further, the image forming apparatus according to the present embodiment may simultaneously perform a plurality of the above-described means.
The image forming apparatus according to the present exemplary embodiment preferably includes a cleaning unit that removes the electrostatic charge image developer remaining on the image carrier.
Examples of the cleaning means include a cleaning blade and a cleaning brush, and a cleaning blade is preferable.

In this image forming apparatus, for example, the part including the developing unit may be a cartridge structure (process cartridge) that is detachable from the main body of the image forming apparatus. As the process cartridge, a developer holding body is used. The process cartridge of the present embodiment is preferably used that includes at least the electrostatic charge image developing developer of the present embodiment.
Hereinafter, although an example of the image forming apparatus of this embodiment is shown, it is not necessarily limited to this. The main parts shown in the figure will be described, and the description of the other parts will be omitted.

FIG. 3 is a schematic configuration diagram showing an embodiment of an image forming apparatus including a developing device to which the toner of the present embodiment is applied.
In FIG. 1, the image forming apparatus of the present embodiment has a photosensitive drum 20 as an image holding member that rotates in a predetermined direction, and the photosensitive drum 20 is charged around the photosensitive drum 20. A charging device 21, for example, an exposure device 22 as a latent image forming device for forming an electrostatic latent image Z on the photosensitive drum 20, and a visible image of the electrostatic latent image Z formed on the photosensitive drum 20. Developing device 30, transfer device 24 that transfers a toner image visualized on photosensitive drum 20 onto recording paper 28 that is a transfer target, and cleaning that cleans residual toner on photosensitive drum 20 The devices 25 are sequentially arranged.

In the present embodiment, as shown in FIG. 3, 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 the developing region 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 this 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 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 latent image Z on the charged photosensitive drum 20, and the developing device 30 then The electrostatic latent 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 that is a transfer target. 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 (not shown) to obtain an image.

  FIG. 4 is a schematic configuration diagram illustrating an example of a process cartridge according to the present embodiment. The process cartridge according to the present embodiment is characterized in that the toner according to the present embodiment is accommodated and a toner holder that holds and conveys the toner is provided.

A process cartridge 200 shown in FIG. 4 includes a photosensitive roller 107 as an image holding member, a charging roller 108, a developing device 111 that accommodates the toner of the above-described embodiment, a photosensitive member cleaning device 113, and an opening 118 for exposure. , And the opening 117 for static elimination exposure is combined and integrated using a mounting rail 116. The process cartridge 200 is detachable from an image forming apparatus main body including a transfer device 112, a fixing device 115, and other components not shown. It constitutes.
In FIG. 4, reference numeral 300 represents a transfer target.

  The process cartridge 200 shown in FIG. 4 includes a charging device 108, a developing device 111, a cleaning device 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. May be combined. In the process cartridge of the present embodiment, in addition to the developing device 111, the photosensitive member 107, the charging device 108, the cleaning device (cleaning means) 113, the opening 118 for exposure, and the opening 117 for static elimination exposure. At least one selected from the group consisting of:

  Next, the toner cartridge of this embodiment will be described. The toner cartridge according to this embodiment is detachably attached to the image forming apparatus, and at least the toner cartridge that stores toner to be supplied to the developing unit provided in the image forming apparatus. The toner according to the exemplary embodiment. It should be noted that at least the toner may be stored in the toner cartridge of the present embodiment, and for example, a developer may be stored depending on the mechanism of the image forming apparatus.

  The image forming apparatus shown in FIG. 3 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, the present embodiment will be described in more detail with reference to examples and comparative examples, but the present embodiment is not limited to these examples.
In the following examples, “part” means “part by weight” and “%” means “% by weight” unless otherwise specified.

<Measurement of average particle diameter, equivalent circle diameter and circularity of glitter pigment>
The average particle diameter, equivalent circle diameter, and circularity of the glitter pigment were measured by the above-described method using FPIA-3000 manufactured by Sysmex.

<Measurement Method of Volume Average Particle Diameter of Carrier and Volume Average Particle Diameter of Toner>
The volume average particle diameter of the carrier was measured using an electron microscope (SEM). More specifically, after obtaining an image by SEM, the diameter (longest part) r ₁ of each particle was measured. After measuring it every 100 obtains the volume to sphere diameter in terms of the r ₁ ~r _100, and the value of the volume average particle diameter when it becomes 50% from the first to 100th.
The volume average particle size of the toner was measured using a Coulter Multisizer II (manufactured by Beckman-Coulter). As the electrolytic solution, ISOTON-II (manufactured by Beckman-Coulter) was used.
As a measuring method, first, 0.5 mg to 50 mg of a measurement sample is added to 2 ml of a 5% aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate as a dispersant, and this is added to 100 ml to 150 ml of the electrolytic solution. Added. The electrolytic solution in which the measurement sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute. Using the Coulter Multisizer II type, an aperture having an aperture diameter of 100 μm is used, and a particle diameter is 2.0 μm to 60 μm. The particle size distribution of the following range of particles was measured. The number of particles to be measured was 50,000.
For the divided particle size range (channel), draw the cumulative distribution from the small diameter side with respect to the divided particle size range (channel), and define the 50% cumulative particle size as the weight average particle size or volume average particle size, respectively. To do.

[Production of toner]
<Synthesis of Binder Resin (1)>
-Dimethyl adipate: 74 parts-Dimethyl terephthalate: 192 parts-Bisphenol A ethylene oxide adduct: 216 parts-Ethylene glycol: 38 parts-Tetrabutoxy titanate (catalyst): 0.037 parts Place in a flask, introduce nitrogen gas into the container, keep the inert atmosphere and raise the temperature while stirring, then carry out a copolycondensation reaction at 160 ° C. for 7 hours, and then gradually increase the pressure to 220 ° C. while gradually reducing the pressure to 10 Torr. Warmed and held for 4 hours. Once the pressure was returned to normal pressure, 9 parts of trimellitic anhydride was added, the pressure was gradually reduced again to 10 Torr, and maintained at 220 ° C. for 1 hour to synthesize binder resin (1).
The glass transition temperature (Tg) of the binder resin (1) is from room temperature (25 ° C.) to 150 ° C. using a differential scanning calorimeter (manufactured by Shimadzu Corporation: DSC-50) in accordance with ASTM D3418-8. It was calculated | required by measuring on temperature rising rate 10 degree-C / min conditions. The glass transition temperature was the temperature at the intersection of the extended line of the base line and the rising line in the endothermic part. The glass transition temperature of the binder resin (1) was 63.5 ° C.

<Preparation of resin particle dispersion (1)>
・ Binder resin (1): 160 parts ・ Ethyl acetate: 233 parts ・ Sodium hydroxide aqueous solution (0.3N): 0.1 part The above ingredients were placed in a 1000 ml separable flask and heated at 70 ° C. A resin mixture was prepared by stirring with Shinto Kagaku Co., Ltd. While further adding this resin mixture at 90 rpm, 373 parts of ion-exchanged water was gradually added, phase-inversion emulsified, and solvent removal was performed to obtain a resin particle dispersion (1) (solid content concentration: 30%). . The volume average particle diameter of the resin particles in the resin particle dispersion (1) was 162 nm.

<Preparation of release agent dispersion>
Carnauba wax (Toa Kasei Co., Ltd., RC-160): 50 parts Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 1.0 parts Ion-exchanged water: 200 parts or more The mixture is heated to 95 ° C. and dispersed using a homogenizer (Ultra Tarax T50, manufactured by IKA). A release agent dispersion (solid content concentration: 20%) prepared by dispersing release agent particles having a particle size of 0.23 μm was prepared.

<Preparation of classified glitter metal pigment>
<< Preparation of classified glitter metal pigment (1) >>
-Dispersion 1-
100 parts of aluminum pigment (Toyo Aluminum Co., Ltd. 0670TS, solid content 50%) (50 parts of aluminum) was added to 500 parts of mineral spirit (Yoneyama Pharmaceutical Co., Ltd.) and stirred at room temperature for 3 hours.

-Classification 1-
Thereafter, the pigment dispersion was put into 1,000 ml of a graduated cylinder and allowed to stand to initiate sedimentation. After standing for 3 hours, 400 parts of the pigment dispersion was taken out from the upper part of the graduated cylinder.

-Dispersion2-
The remaining 100 parts of the pigment dispersion was dispersed in 400 parts of mineral spirit and stirred for 1 hour.

-Classification 2-
Thereafter, the pigment dispersion was put into 1,000 ml of a graduated cylinder and allowed to stand for 3 hours, and then 400 parts of the pigment dispersion was taken out from the upper part of the graduated cylinder.

-Dispersion 3-
The operation of dispersion 2 was repeated.

-Separation-
The remaining 100 parts of the pigment dispersion was filtered, washed with acetone, filtered and dried to remove mineral spirits. The average equivalent circle diameter of the dried pigment, the number of particles with an equivalent circle diameter of 4 μm or less, the average circularity, and the number of particles with a circularity of 0.850 or less were measured with FPIA-3000. The measurement results are shown in Table 1.

<< Preparation of classified glitter metal pigment (2) >>
A classified glitter metal pigment (2) was prepared in the same manner as the classified glitter metal pigment (1) except that the standing time for classification was changed from 3 hours to 1 hour.

<< Preparation of classified glitter metal pigment (3) >>
A classified glitter metal pigment (3) was prepared in the same manner as the classified glitter metal pigment (1) except that the standing time for classification was changed from 3 hours to 5 hours.

<< Preparation of classified glitter metal pigment (4) >>
Classified glittering metallic pigments (except that mineral oil was replaced with silicone oil (KF-96-50cs) (manufactured by Shin-Etsu Chemical Co., Ltd.) and the standing time for classification was changed from 3 hours to 1 hour. In the same manner as 1), a classified glittering metal pigment (4) was prepared.

<< Preparation of classified glitter metal pigment (5) >>
A classified glittering metal pigment (with the exception of using a silicone oil (KF-96-50cs) (manufactured by Shin-Etsu Chemical Co., Ltd.) instead of mineral spirits and changing the standing time of classification from 3 hours to 5 hours ( In the same manner as 1), a classified glittering metal pigment (5) was prepared.

<< Preparation of classified glitter metal pigment (6) >>
A classified glitter metal pigment (6) was prepared in the same manner as the classified glitter metal pigment (1) except that the dispersion and the classification were performed twice.

<< Preparation of classified glitter metal pigment (7) >>
Classified glittering metal pigment (1), except that silicone oil (KF-96-50cs) (manufactured by Shin-Etsu Chemical Co., Ltd.) was used instead of mineral spirit, and dispersion and classification were each performed twice. In the same manner, a classified glittering metal pigment (7) was prepared.

<< Preparation of classified glitter metal pigment (8) >>
A classified glitter metal pigment (8) was prepared in the same manner as the classified glitter metal pigment (1) except that the standing time for classification was changed from 3 hours to 0.5 hour.

<< Preparation of classified glitter metal pigment (9) >>
A classified glitter metal pigment (9) was prepared in the same manner as the classified glitter metal pigment (1) except that the standing time for classification was changed from 3 hours to 7 hours.

<< Preparation of classified glitter metal pigment (10) >>
A classified glittering metal pigment (except for mineral spirits), except that silicone oil (KF-96-50cs) (manufactured by Shin-Etsu Chemical Co., Ltd.) was used and the standing time for classification was changed from 3 hours to 7 hours. A classified glitter metal pigment (10) was prepared in the same manner as in 1).

<< Preparation of classified glitter metal pigment (11) >>
A classified glitter metal pigment (11) was prepared in the same manner as the classified glitter metal pigment (1) except that the dispersion and the classification were each performed once.

<< Preparation of classified glitter metal pigment (12) >>
The classified glitter metal pigment (1), except that silicone oil (KF-96-50cs) (manufactured by Shin-Etsu Chemical Co., Ltd.) was used instead of mineral spirit, and dispersion and classification were each performed once. In the same manner, a classified glittering metal pigment (12) was prepared.

<Preparation of glitter pigment particle dispersion>
<< Preparation of glitter pigment particle dispersion (1) >>
・ Classified glitter metal pigment (1): 100 parts ・ Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen R): 1.5 parts ・ Ion-exchanged water: 900 parts Solvent from paste of aluminum pigment The above is mixed and dissolved, and dispersed for about 1 hour using an emulsifier-dispersing machine Cavitron (manufactured by Taiheiyo Kiko Co., Ltd., CR1010) to disperse glitter pigment particles (aluminum pigment). A bright pigment particle dispersion (solid content concentration: 10%) was prepared.

<< Preparation of glitter pigment particle dispersions (2) to (12) >>
The bright pigment is the same as the bright pigment particle dispersion (1) except that the classified bright metal pigments (2) to (12) are used instead of the classified bright metal pigment (1). Particle dispersions (2) to (12) were prepared.

<Preparation of cyan colorant dispersion>
・ C. I. Pigment Blue 15: 3 (copper phthalocyanine) (manufactured by Dainichi Seika Kogyo Co., Ltd.): 50 parts, ionic surfactant Neogen RK (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.): 5 parts, ion-exchanged water: 192. 9 parts The above components were mixed and treated with an optimizer (manufactured by Sugino Machine) at 240 MPa for 10 minutes to obtain a cyan colorant dispersion (solid content concentration: 20%).

<Preparation of magenta colorant dispersion>
The colorant is C.I. I. Pigment Blue 15: 3 to C.I. I. A magenta colorant dispersion was prepared in the same manner as the preparation of the cyan colorant dispersion, except that Pigment Red 122 (quinacridone) (manufactured by Dainichi Seika Kogyo Co., Ltd.) was used. The solid content concentration was 20%.

Example 1
<Production of toner>
-Resin particle dispersion: 325 parts-Release agent dispersion: 48.5 parts-Bright pigment dispersion (1): 180 parts-Nonionic surfactant (IGEPAL CA897, manufactured by Rhodia): 1.40 parts The raw material was placed in a cylindrical stainless steel container, and dispersed and mixed for 10 minutes while applying a shearing force at 4,000 rpm with a homogenizer (manufactured by IKA, Ultra Turrax T50). Subsequently, 1.75 parts of a 10% nitric acid aqueous solution of polyaluminum chloride as a flocculant was gradually added dropwise, and the homogenizer was rotated at 5,000 rpm and dispersed for 15 minutes to prepare a raw material dispersion.
Thereafter, the raw material dispersion is transferred to a polymerization kettle equipped with a stirrer using two paddle stirring blades and a thermometer, and heated at a mantle heater at a stirring rotation speed of 810 rpm, and agglomerated at 54 ° C. Promoted particle growth. At this time, the pH of the raw material dispersion was controlled in the range of 2.2 to 3.5 with 0.3N nitric acid or 1N sodium hydroxide aqueous solution. The agglomerated particles were formed by maintaining the above pH range for about 2 hours.
Next, 50 parts of a resin particle dispersion was additionally added, and the resin particles of the binder resin were adhered to the surface of the aggregated particles. The temperature was further raised to 56 ° C., and aggregated particles were prepared while confirming the size and form of the particles with an optical microscope and Multisizer II. Thereafter, the pH was raised to 8.0 in order to fuse the aggregated particles, and then the temperature was raised to 67.5 ° C. After confirming that the aggregated particles were fused with an optical microscope, the pH was lowered to 6.0 while maintaining the temperature at 67.5 ° C., and the heating was stopped after 1 hour, followed by cooling at a rate of temperature decrease of 1.0 ° C./min. Thereafter, the mixture was sieved with a 20 μm mesh, washed repeatedly with water, and then dried with a vacuum dryer to obtain toner particles. The obtained toner particles had a volume average particle diameter of 12.2 μm. In addition, it was confirmed that the toner particles are flat and have an average equivalent circle diameter D longer than the average maximum thickness C thereof.

  To 100 parts of the obtained toner particles, 2.0 parts of hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., RY50) was mixed for 3 minutes at a peripheral speed of 30 m / s using a Henschel mixer. Thereafter, the toner was prepared by sieving with a vibrating sieve having an opening of 45 μm.

<Creation of carrier>
Ferrite particles (volume average particle diameter: 35 μm): 100 parts Toluene: 14 parts Perfluoroacrylate copolymer (critical surface tension: 24 dyn / cm): 1.6 parts Carbon black (trade name: VXC-72 , Manufactured by Cabot Corporation, 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, carbon is added to the perfluoroacrylate copolymer. Black was diluted in 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, the coating layer forming solution and the 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, thereby forming a resin coating layer and carrier. Obtained.

<Production of developer>
36 parts of the toner and 414 parts of the carrier were placed in a V blender, stirred for 20 minutes, and then sieved at 212 μm to prepare a developer.

(Examples 2-7 and Comparative Examples 1-5)
A toner and a developer were prepared in the same manner as in Example 1 except that the bright pigment dispersion according to Table 1 was used instead of the bright pigment dispersion (1).

<Manufacture of cyan toner>
Binder resin dispersion: 400 parts Cyan colorant dispersion: 35 parts Release agent dispersion 1:80 parts Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 1. 30 parts The above raw materials were placed in a cylindrical stainless steel container and dispersed and mixed for 10 minutes while applying a shearing force at 4,000 rpm with a homogenizer (manufactured by IKA, Ultra Lalux T50). Subsequently, 0.14 part of a 10% nitric acid aqueous solution of polyaluminum chloride as a flocculant began to be dropped to promote preaggregation.
Next, the raw material dispersion was transferred to a polymerization kettle equipped with a stirrer and a thermometer, and started to be heated with a mantle heater, and kept at 52 ° C. for 2 hours to promote the growth of aggregated particles. Thereafter, 190 parts of a binder resin dispersion was additionally added, and the resin particles of the binder resin were adhered to the surface of the aggregated particles. Aggregated particles were prepared while confirming the particle diameter with an optical microscope and Multisizer II.
Thereafter, the pH was raised to 8.5 in order to fuse the aggregated particles, and then the temperature was raised to 90 ° C. After the temperature increase, the temperature was maintained at 90 ° C. for 3 hours, and after confirming that the particles were fused with a microscope, the pH was lowered to 6.5 again while maintaining the temperature at 90 ° C., the heating was stopped after 1 hour, and the mixture was allowed to cool. . Thereafter, the mixture was sieved with a 20 μm mesh, washed repeatedly with water, and then dried with a vacuum dryer. The toner particles granulated as described above had a volume average particle diameter of 7.3 μm.
To 100 parts of the obtained toner particles, 1.5 parts of hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., RY50) was mixed and blended at 10,000 rpm for 30 seconds using a sample mill. Thereafter, the yellow toner was prepared by sieving with a vibration sieve having an opening of 45 μm.

<Manufacture of cyan developer>
Carrier and cyan toner were mixed in a V blender at a ratio of 100 parts: 8 parts, respectively, to produce a yellow developer.

<Manufacture of magenta toner>
A magenta toner was produced in the same manner as the cyan toner except that the cyan colorant dispersion was changed to a magenta colorant dispersion. Using the obtained magenta toner, a magenta developer was produced in the same manner as in the case of the cyan developer.

<Evaluation test>
-Formation of solid images-
A solid image was formed by the following method.
The developer obtained in each example is filled in a developing device of DocuCentre-III C7600 manufactured by Fuji Xerox Co., Ltd., and the fixing temperature is 190 ° C. on recording paper (OK topcoat + paper, manufactured by Oji Paper Co., Ltd.). A solid image having a toner loading of 4.5 g / cm ² is formed at a fixing pressure of 4.0 kg / cm ² . The “solid image” refers to an image with a printing rate of 100%.

-Measurement of brightness of solid image-
The brightness of the solid image was measured using X-Rite 938 manufactured by X-Rite as a spectrocolorimeter for the formed solid image. The results are shown in Table 1.

-Evaluation of glitter-
Illumination for color observation in accordance with JIS K 5600-4-3: 1999 “Paint general test method-Part 4: Visual characteristics of coating film-Section 3: Visual comparison of colors” (natural nature) The brightness was visually evaluated under daylight illumination. The evaluation was carried out by evaluating the particle feeling (the effect of glittering glitter) and the optical effect (the change in hue depending on the viewing angle), and the following stages. Two or more are actually usable levels.
The obtained results are shown in Table 1.

-Evaluation criteria-
5: Particle sensation and optical effect are in harmony 4: Slight particle sensation, optical effect 3: Normal sensation 2: Blurred feeling 1: No particle sensation, no optical effect

-Measurement of saturation at a hue angle of 270 °-
The developer of DocuCentre-III C7600 manufactured by Fuji Xerox Co., Ltd. was filled using a cyan developer, a magenta developer, and the bright toner developer of Example or Comparative Example. The glitter toner developer is put in a black developer, and the glitter toner image is developed so that the solid image (toner applied amount) is 4.5 g / cm ^2, and the cyan toner and the magenta toner are half-finished thereon. A tone image is formed, and an image having a hue angle of 270 ° is formed on a recording paper (OK topcoat + paper, manufactured by Oji Paper Co., Ltd.) at a fixing temperature of 190 ° C. and a fixing pressure of 4.0 kg / cm ² . did. For the formed image, the maximum saturation of the image was measured using X-Rite 938 manufactured by X-Rite as a spectrocolorimeter. The results are shown in Table 1.

  In the present embodiment, a color image having high brightness and high saturation could be obtained. On the other hand, in the comparative example, the brightness was inferior or the saturation of the color image was inferior.

  T: toner, MP: glitter pigment, L: toner thickness, 20: photoconductor (image carrier) drum, 21: charging device, 22: exposure device, 24: transfer device, 25: cleaning device, 28: Recording paper, 30: development device, 31: development housing, 32: development opening, 33: development roll, 34: charge injection roll, 40: toner, 107: photoconductor (image carrier), 108: charging roller, 111 : Developing device (developing means), 112: transfer device, 113: photoconductor cleaning device (cleaning means), 115: fixing device (fixing means), 116: mounting rail, 117: opening for static elimination exposure, 118: Opening for exposure, 200: process cartridge, 300: recording paper (transfer object), Z: electrostatic latent image

Claims (1)

A dispersion step of dispersing the glitter pigment in the liquid;
A classifying step of spontaneously precipitating the dispersed bright pigment to separate and classify a pigment having a slow sedimentation rate; and
A separation step of separating the classified glitter pigment from the liquid,
The dispersion step, the classification step and the separation step are repeated twice or more.
The average equivalent circle diameter is 6 μm to 15 μm, the number of particles having an equivalent circle diameter of 4 μm or less is 20% by number or less, the average circularity is 0.900 to 0.980, and the circularity is 0.850 or less. A method for producing a luster pigment in which the number of particles is 20% or less .

Images