JP2019008123A - toner - Google Patents

Abstract

To provide a toner using a photoluminescent colorant, excellent in charge uniformity and capable of stably forming a high quality image regardless of change in use environment.SOLUTION: The toner has toner particles including a binder resin, aluminum fine particles and silica fine particles. The weight average particle diameter (D4) of the toner particles is from 3.0 μm or more to 10.0 μm; the toner particle includes the aluminum fine particles and the silica fine particles in an inner region of 0.3 μm or more from the surface of the toner particle; the content of the aluminum fine particles in the toner particle is 5.0 pts.mass or more and 30.0 pts.mass or less to the toner particles of 100 pts.mass; and the content of the silica particles in the toner particle is from 0.1 pt.mass or more to 2.5 pts.mass to the toner particles of 100 pts.mass.SELECTED DRAWING: None

Description

  The present invention relates to a toner used in an electrophotographic image forming apparatus.

  In recent years, an electrophotographic image forming apparatus that forms a toner image on a transfer material using not only normal toners such as yellow, magenta, cyan, and black, but also bright toner having metallic luster has been proposed. As a result, the hue of the image becomes clearer and various expressions can be achieved by combining with normal toner.

Patent Document 1 discloses a toner including aluminum fine particles having an average aspect ratio (major axis / minor axis) of 1.2 to 15 and an average major axis D _50n of 200 nm to 400 nm as a bright colorant. Has been.

  Patent Documents 2 and 3 disclose techniques for suppressing image unevenness by adding a small amount of phosphorus (P) or zinc (Zn) to aluminum fine particles.

JP 2013-134314 A Japanese Patent Laid-Open No. 2015-36747 Japanese Patent Laying-Open No. 2015-52650

  However, the bright colorant (aluminum fine particles) disclosed in Patent Document 1 tends to be positively charged, and when used in a negative toner, the toner is not uniformly charged and the charge amount distribution is likely to be broad. As a result, a fogging phenomenon to a non-image portion may be caused, the follow-up ability of the charge amount due to a change in use environment may be low, and the stability of the image density immediately after the power is turned on may be lowered.

  In the techniques disclosed in Patent Documents 2 and 3, the charging stability in the use environment is insufficient, the image density may fluctuate due to the change in the use environment, or the fog phenomenon may occur. there were.

  An object of the present invention is to provide a toner that is excellent in charging uniformity even in a toner using a bright colorant and can stably form a high-quality image regardless of changes in the use environment.

The present invention is a toner having toner particles containing a binder resin, aluminum fine particles and silica fine particles,
The toner particles have a weight average particle diameter (D4) of 3.0 μm or more and 10.0 μm,
The toner particles contain the aluminum fine particles and the silica fine particles in an inner region of 0.3 μm or more from the surface of the toner particles,
The content of the aluminum fine particles in the toner particles is 5.0 parts by mass or more and 30.0 parts by mass or less with respect to 100 parts by mass of the toner particles.
The toner is characterized in that the content of the silica fine particles in the toner particles is 0.1 parts by mass or more and 2.5 parts by mass or less with respect to 100 parts by mass of the toner particles.

  According to the present invention, even a toner using a bright colorant can provide a toner that is excellent in charging uniformity and can stably form a high-quality image regardless of changes in the use environment.

It is the schematic of a thermal spheronization processing apparatus.

The toner of the present invention is
A toner having toner particles containing a binder resin, aluminum fine particles and silica fine particles,
The toner particles have a weight average particle diameter (D4) of 3.0 μm or more and 10.0 μm,
The toner particles contain the aluminum fine particles and the silica fine particles in an inner region of 0.3 μm or more from the surface of the toner particles,
The content of the aluminum fine particles in the toner particles is 5.0 parts by mass or more and 30.0 parts by mass or less with respect to 100 parts by mass of the toner particles.
The content of the silica fine particles in the toner particles is 0.1 to 2.5 parts by mass with respect to 100 parts by mass of the toner particles.

  The present inventors have made it possible to neutralize the positive chargeability of aluminum fine particles by coexisting aluminum fine particles, which are bright colorants, and silica fine particles in the toner particles, and to have excellent charging uniformity. It was found that can be obtained.

  One of the characteristics of the present invention is that the toner particles contain aluminum fine particles and silica fine particles in a region (hereinafter also referred to as “the vicinity of the toner particle surface”) of 0.3 μm or more from the surface of the toner particles (internal addition). Is). The content (internal addition amount) of aluminum fine particles in the toner particles is 5.0 parts by mass or more and 30.0 parts by mass or less with respect to 100 parts by mass of the toner particles. Further, the content (internal addition amount) of silica fine particles in the toner particles is 0.1 parts by mass or more and 2.5 parts by mass or less with respect to 100 parts by mass of the toner particles.

  When the content of aluminum fine particles in the toner particles is less than 5.0 parts by mass, sufficient coloring power cannot be given to the toner. When the content is more than 30.0 parts by mass, even if silica particles are present in the toner particles, the positive chargeability of the toner is increased, and the toner charging uniformity is insufficient.

  In addition, when the content of silica fine particles in the toner particles is less than 0.1 parts by mass, the charge neutralizing action on the aluminum fine particles is reduced, the toner positive chargeability is increased, and the toner charge uniformity is insufficient. It becomes. On the other hand, when the content is more than 2.5 parts by mass, the toner is easily overcharged in a low humidity environment. When the toner is excessively charged, the density of the image is lowered.

  The toner particles according to the present invention preferably contain 2.5 parts by mass or more and 7.0 parts by mass or less of silica fine particles in the vicinity of the surface of the toner particles. By disposing silica fine particles in the vicinity of the surface of the toner particles, the influence of temperature and humidity accompanying the change in the use environment can be reduced, and excellent charging uniformity can be exhibited in various environments.

The average aspect ratio (major axis / minor axis) of the aluminum fine particles is preferably 1.2 or more and 15 or less. Further, the average major axis D _50n of the aluminum fine particles is preferably 200 nm or more and 400 nm or less.

  If the average aspect ratio of the aluminum fine particles is 1.2 or more, the color development area becomes large, and a sufficient glitter effect is easily obtained. Further, when the aspect ratio is 15 or less, it is difficult to form a needle-like body, and therefore, it is difficult to damage a member such as a photoconductor. A scratch generated on a member such as a photoconductor tends to cause toner fusion or the like starting from the scratch.

In addition, when the average diameter D _50n of the aluminum fine particles is 200 nm or more, the color development area becomes large, and a sufficient glitter effect is easily obtained. Further, when D _50n is 400 nm or less, the dispersibility of the aluminum fine particles in the toner particles is enhanced, and it becomes difficult to cause a charging failure.

The average aspect ratio (major axis / minor axis) of the silica fine particles is preferably 1.0 or more and 1.2 or less. Further, the average _long diameter D _50n of the silica fine particles is preferably 30 nm or more and 200 nm or less.

  If the average of the aspect ratio (major axis / minor axis) of the inorganic fine particles A is 1.2 or less, it becomes difficult to damage a member such as a photoreceptor. Further, the mixing with the aluminum fine particles as the bright colorant becomes good, and it is difficult to cause poor charging.

Further, if the average D _50n of the major axis of the silica fine particles is 30 nm or more, the charge neutralizing action on the colorant becomes stronger and it is difficult to cause a charging failure. Further, if the average D _50n of the major axis of the silica fine particles is 200 nm or less, the dispersibility of the silica fine particles in the toner particles is enhanced, and the charging stability of the toner is further enhanced.

[Binder resin]
As the binder resin, for example,
A homopolymer of styrene or a substituted product (derivative) thereof such as polystyrene, poly-p-chlorostyrene, and polyvinyltoluene;
Styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethacrylic acid Acid methyl copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-acrylonitrile-indene copolymer, etc. Styrenic copolymer;
PVC;
Phenolic resin;
Naturally modified phenolic resin;
Natural resin-modified maleic resin;
acrylic resin;
Methacrylic resin;
Polyvinyl acetate;
Silicone resin;
Polyester resin;
Polyurethane resin;
Polyamide resin;
Furan resin;
Epoxy resin;
Xylene resin;
Polyvinyl butyral;
Terpene resin;
Coumarone-indene resin;
Examples include petroleum resins.

  Among these, polyester resins and hybrid resins of polyester and vinyl polymers are preferable from the viewpoints of low-temperature fixability and chargeability control.

  In the present invention, the polyester resin is a resin having a “polyester unit” in the resin chain. Examples of the unit constituting the polyester unit include units derived from a divalent or higher valent alcohol monomer component, and acid monomers such as a divalent or higher carboxylic acid, a divalent or higher carboxylic acid anhydride, and a divalent or higher carboxylic acid ester. And component-derived units.

Examples of the bivalent or higher alcohol monomer component include:
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2. 0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (6) alkylene oxide adducts of bisphenol A such as -2,2-bis (4-hydroxyphenyl) propane, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1 , 4-butanediol, neopentyl glycol, 1,4-butenedio 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, sorbit, 1,2,3,6-hexanete Trol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl-1 2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene and the like.

  Among these, aromatic diols are preferable. In the unit derived from the alcohol monomer component constituting the polyester resin, the unit derived from the aromatic diol preferably occupies a ratio of 80 mol% or more.

Examples of acid monomer components such as divalent or higher carboxylic acid, divalent or higher carboxylic acid anhydride and divalent or higher carboxylic acid ester include:
Aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid or anhydrides thereof;
Alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid and azelaic acid or anhydrides thereof;
Succinic acid or anhydride thereof substituted with an alkyl or alkenyl group having 6 to 18 carbon atoms;
Examples thereof include unsaturated dicarboxylic acids such as fumaric acid, maleic acid and citraconic acid or anhydrides thereof.

  Among these, polyvalent carboxylic acids such as terephthalic acid, succinic acid, adipic acid, fumaric acid, trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid or their anhydrides are preferable.

  The acid value of the polyester resin is preferably 1 mgKOH / g or more and 20 mgKOH / g or less from the viewpoint of the stability of the triboelectric charge amount.

  The acid value of the polyester resin can be controlled by adjusting the type and amount of the monomer used for the production of the polyester resin. For example, it can be controlled by adjusting the ratio between the alcohol monomer component and the acid monomer component during the production of the polyester resin and the molecular weight of the polyester resin. Moreover, it can also control by making terminal alcohol and a polyhydric acid monomer (for example, trimellitic acid) react after ester condensation polymerization.

  As a method for obtaining a hybrid resin of polyester and vinyl polymer, there is a method of performing a polymerization reaction for producing a vinyl polymer and / or polyester in the presence of a vinyl polymer and / or a monomer component capable of reacting with polyester. preferable.

[wax]
The toner particles according to the present invention may contain a wax.

As a wax, for example,
Hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, alkylene copolymers, microcrystalline wax, paraffin wax, Fischer-Tropsch wax;
Oxides of hydrocarbon waxes such as oxidized polyethylene wax or block copolymers thereof;
Waxes based on fatty acid esters such as carnauba wax;
Deoxidized part or all of fatty acid esters such as deoxidized carnauba wax;
Saturated linear fatty acids such as palmitic acid, stearic acid, and montanic acid;
Unsaturated fatty acids such as brassic acid, eleostearic acid, valinalic acid;
Saturated alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol, melyl alcohol;
Polyhydric alcohols such as sorbitol;
Esters of fatty acids such as palmitic acid, stearic acid, behenic acid, montanic acid, and alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol, melyl alcohol;
Fatty acid amides such as linoleic acid amide, oleic acid amide, 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;
Unsaturated fatty acid amides such as ethylene bis oleic acid amide, hexamethylene bis oleic acid amide, N, N ′ dioleyl adipic acid amide, N, N ′ dioleyl sebacic acid amide;
aromatic bisamides such as m-xylene bis-stearic acid amide and N, N ′ distearyl isophthalic acid amide;
Aliphatic metal salts (commonly called metal soaps) such as calcium stearate, calcium laurate, zinc stearate, magnesium stearate;
Waxes grafted to aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid;
Partial esterified product of fatty acid and polyhydric alcohol such as behenic acid monoglyceride;
Examples include methyl ester compounds having a hydroxyl group obtained by hydrogenation of vegetable oils.

  Among these, hydrocarbon waxes such as paraffin wax and Fischer-Tropsch wax are preferable from the viewpoint of improving low-temperature fixability and fixing member wrapping property.

  The content of the wax in the toner particles is preferably 0.5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin in the toner particles.

  From the viewpoint of coexistence of storage stability of toner and high temperature offset property, the maximum endothermic peak existing in the range of 30 ° C. to 200 ° C. in the endothermic curve at the time of temperature rise measured by a differential scanning calorimeter (DSC). The peak temperature is preferably 50 ° C. or higher and 110 ° C. or lower.

[Charge control agent]
The toner particles according to the present invention may contain a charge control agent.

  The charge control agent is preferably a metal compound of an aromatic carboxylic acid that is colorless, has a high toner charging speed, and can stably maintain the charge amount.

As a negative charge control agent, for example,
A polymeric compound having a side chain of a salicylic acid metal compound, a naphthoic acid metal compound, a dicarboxylic acid metal compound, a sulfonic acid or a carboxylic acid;
A polymer type compound having a sulfonate or a sulfonated ester in the side chain;
A polymer compound having a carboxylate or a carboxylate ester in the side chain;
Boron compounds;
Urea compounds;
Silicon compounds;
Examples include calix arene.

  The charge control agent may be added internally or externally to the toner particles.

  The content of the charge control agent in the toner particles is preferably 0.2 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the binder resin in the toner particles.

[External additive]
The toner of the present invention may have an external additive for improving fluidity and adjusting the triboelectric charge amount.

  Examples of the external additive include inorganic fine particles such as silicon oxide (silica), titanium oxide (titania), aluminum oxide (alumina), and strontium titanate.

  The external additive (inorganic fine particles) is preferably hydrophobized with a hydrophobizing agent such as a silane compound, silicone oil, or a mixture thereof.

The specific surface area of the external additive (inorganic fine particles) is preferably 10 m ² / g or more and 50 m ² / g or less from the viewpoint of suppressing embedding of the external additive (inorganic fine particles).

  The content of the external additive in the toner is preferably 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the toner particles.

[Career]
The toner of the present invention is preferably mixed with a magnetic carrier and used as a two-component developer from the viewpoint that a stable image can be obtained over a long period of time.

Examples of magnetic carriers include:
Oxidized iron powder or non-oxidized iron powder;
Metal particles such as iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, rare earth, or alloy particles or oxide particles thereof;
Magnetic material such as ferrite;
Magnetic material-dispersed resin carrier (so-called resin carrier) containing a magnetic material and a binder resin that holds the magnetic material in a dispersed state
Etc.

[Production method]
Examples of the method for producing the toner of the present invention include an emulsion aggregation method, a melt kneading method, and a dissolution suspension method.

  Among these, the melt kneading method is preferable from the viewpoint of dispersibility of raw materials.

  The melt-kneading method is characterized in that a toner composition that is a raw material of toner particles is melt-kneaded, and the obtained kneaded product is pulverized.

  The melt kneading method will be described in more detail.

  In the raw material mixing step, a predetermined amount of components such as a binder resin, aluminum fine particles and silica fine particles and, if necessary, wax, colorant, and the like are weighed and mixed as raw materials for toner particles. Examples of the mixing device include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, a nauter mixer, and a mechano hybrid (manufactured by Nippon Coke Industries, Ltd.).

  Next, the mixed material is melt-kneaded to disperse other raw materials in the binder resin.

  In the melt-kneading step, for example, a batch kneader such as a pressure kneader or a Banbury mixer, or a continuous kneader can be used. Due to the advantage of continuous production, single-screw or twin-screw extruders are the mainstream.

As an extruder, for example,
KTK type twin screw extruder (manufactured by Kobe Steel, Ltd.), TEM type twin screw extruder (manufactured by Toshiba Machine Co., Ltd.), PCM kneading machine (manufactured by Ikekai Co., Ltd.), twin screw extruder (Kay Sea)・ Kei Co., Ltd., Ko Kneader (Bus Co., Ltd.), Kneedex (Nihon Coke Industries Co., Ltd.)
Etc.

  The resin composition obtained by melt-kneading is rolled with two rolls. Furthermore, you may cool a resin composition with water etc. at a cooling process.

  Next, the cooled product of the resin composition is pulverized to a desired particle size in a pulverization step.

  In the pulverization step, the material is roughly pulverized by a pulverizer and further pulverized by a fine pulverizer. Examples of the pulverizer used for coarse pulverization include a crusher, a hammer mill, and a feather mill. Examples of the pulverizer used for pulverization include a kryptron system (manufactured by Kawasaki Heavy Industries, Ltd.), a super rotor (manufactured by Nissin Engineering Co., Ltd.), a turbo mill (manufactured by Turbo Industry Co., Ltd.), and an air jet. Examples include a fine pulverizer.

  Thereafter, classification is performed using a classifier or a sieving machine as necessary to obtain toner particles.

Examples of classifiers and sieving machines include:
Inertial classification type elbow jet (manufactured by Nippon Steel & Mining Co., Ltd.), centrifugal force classification type turboplex (manufactured by Hosokawa Micron Corporation), TSP separator (manufactured by Hosokawa Micron Corporation), Faculty (manufactured by Hosokawa Micron Corporation)
Etc.

Also, after grinding, if necessary,
Hybridization system (manufactured by Nara Machinery Co., Ltd.), mechano-fusion system (manufactured by Hosokawa Micron Co., Ltd.), Faculty (manufactured by Hosokawa Micron Co., Ltd.), Meteor Inbo MR Type (manufactured by Nippon Pneumatic Industry Co., Ltd.)
The surface treatment of the toner particles such as a spheroidization treatment can also be performed.

  In the present invention, additives such as inorganic fine particles and resin particles are added to the surface of the toner particles obtained by the above production method, mixed and dispersed, and in the dispersed state, the additive is subjected to surface treatment with hot air. It is preferable to fix it on the surface of the toner particles.

  For example, the toner can be obtained by performing surface treatment with hot air using the thermal spheronization processing apparatus shown in FIG. 1 and classifying as necessary.

  In the thermal spheronization processing apparatus shown in FIG. 1, the mixture (raw material) quantitatively supplied by the raw material supply means 1 is placed on the vertical line of the raw material supply means 1 by the compressed gas adjusted by the compressed gas adjusting means 2. It is guided to the introduction pipe 3. The mixture that has passed through the introduction pipe 3 is uniformly dispersed by a conical protrusion-like member 4 provided at the center of the raw material supply means 1, and is guided to an eight-direction supply pipe 5 that spreads radially, and heat treatment is performed. Guided to the processing chamber 6.

  At this time, the flow of the mixture supplied to the processing chamber 6 is regulated by the regulating means 9 for regulating the flow of the mixture provided in the processing chamber 6. For this reason, the mixture supplied to the processing chamber 6 is cooled after being heat-treated while turning inside the processing chamber.

  Heat for heat-treating the supplied mixture is supplied as hot air from the hot air supply means 7 and distributed by the distribution member 12. Hot air is swirled and introduced into the processing chamber 6 by a swirling member 13 for swirling the hot air. As the structure, the turning member 13 has a plurality of blades, and the turning of hot air can be controlled by the number and angle of the blades. The temperature of the hot air supplied into the processing chamber 6 is preferably 100 ° C. or higher and 300 ° C. or lower, more preferably 130 ° C. or higher and 170 ° C. or lower, at the outlet of the hot air supply means 7. If the temperature at the outlet of the hot air supply means 7 is within the above range, the toner particles are uniformly spheroidized (thermal spheronization) while suppressing fusion and coalescence of the toner particles due to excessive heating of the mixture. Easy to handle. The circularity at this time is preferably 0.955 or more and 0.980 or less. Hot air is supplied from the hot air supply means outlet 11.

The heat-treated toner particles subjected to the heat treatment are cooled by the cold air supplied from the cold air supply means 8. The temperature of the cold air supplied from the cold air supply means 8 is preferably −20 ° C. or higher and 30 ° C. or lower. When the temperature of the cold air is within the above range, the heat-treated toner particles can be efficiently cooled, and the uniform spheroidization (thermal spheronization) treatment of the mixture is hardly hindered. One can be suppressed. The absolute moisture content of the cold air is preferably 0.5 g / m ³ or more and 15.0 g / m ³ or less.

  Next, the cooled heat-treated toner particles are recovered by the recovery means 10 at the lower end of the processing chamber. In addition, a blower (not shown) is provided at the tip of the collecting means 10 so that it is sucked and conveyed.

  The powder particle supply port 14 is provided so that the swirling direction of the supplied mixture and the swirling direction of the hot air are the same direction. The collection means 10 is provided on the outer periphery of the processing chamber 6 so as to maintain the swirling direction of the swirled powder particles. Further, the cold air supplied from the cold air supply means 8 is configured to be supplied from the outer peripheral portion of the apparatus to the inner peripheral surface of the processing chamber 6 from the horizontal and tangential directions. The swirling direction of the pre-heat treatment toner particles supplied from the powder particle supply port 14, the swirling direction of the cold air supplied from the cold air supplying means 8, and the swirling direction of the hot air supplied from the hot air supplying means 7 are all the same direction. It is. As a result, turbulent flow does not occur inside the processing chamber 6, the swirling flow in the apparatus is strengthened, a strong centrifugal force is applied to the toner particles before heat treatment, and the dispersibility of the toner particles before heat treatment is further improved. Therefore, it is possible to obtain heat-treated toner particles having a small number of coalesced particles and having a uniform shape.

  Thereafter, external additives such as inorganic fine particles and resin particles may be added and mixed to improve the fluidity and charging stability of the toner. Examples of the mixing device include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, a nauter mixer, and a mechano hybrid (manufactured by Nihon Coke Industries Co., Ltd.).

<Measurement of aspect ratio (major axis / minor axis) of aluminum fine particles and silica fine particles and average D _50n of major axis>
The average _long diameter D _50n of the aluminum fine particles and the silica fine particles is observed with a transmission electron microscope, the particle diameter of 100 particles is measured, and the average value of the long axis length is determined as the average long diameter D _50n . did. Similarly, the average value of the lengths of the short axes was obtained and used as the average of the short diameters. The aspect ratio was obtained by dividing the major axis (major axis length) by the minor axis (minor axis length).

<Measurement Method of Content (Internal Addition) of Aluminum Fine Particles and Silica Fine Particles near the Surface of Toner Particles>
2 mL of nonionic surfactant (trade name: Contaminone N, manufactured by Wako Pure Chemical Industries, Ltd.) is added to 200 mL of ion-exchanged water, and dispersion treatment is performed for 10 hours using an ultrasonic disperser. In this way, the total amount of the external additive of the toner is released, and the content of aluminum fine particles and silica fine particles present inside the toner particles is calculated by fluorescent X-ray measurement.

  The measurement of the fluorescent X-ray of each element is based on JIS K0119-1969. Specifically, it is as follows.

As a measuring device,
A wavelength dispersive X-ray fluorescence analyzer (trade name: Axios, manufactured by PANalytical);
Attached dedicated software (trade name: SuperQ ver. 4.0F, manufactured by PANalytical) is used for setting measurement conditions and analyzing measurement data. Also, Rh is used as the anode of the X-ray tube, the measurement atmosphere is vacuum, the measurement diameter (collimator mask diameter) is 27 mm, and the measurement time is 10 seconds. When the light element is measured with the same apparatus, it is detected with a proportional counter (PC), and when the heavy element is measured, it is detected with a scintillation counter (SC).

  As a measurement sample, about 4 g of toner is put in a dedicated aluminum ring for pressing and leveled. Then, using a tablet molding compressor (trade name: BRE-32, manufactured by Maekawa Test Instruments Co., Ltd.), pressurization is performed at 20 MPa for 60 seconds, and pellets molded to a thickness of about 2 mm and a diameter of about 39 mm are used.

  Measurement is performed under the above conditions, the element is identified based on the obtained X-ray peak position, and the concentration of the element is calculated from the count rate (unit: cps) which is the number of X-ray photons per unit time. .

  In the case of aluminum fine particles, aluminum fine particles are added to 5.0 parts by mass with respect to 100 parts by mass of the toner particles, and are mixed using a coffee mill. Similarly, aluminum fine particles are mixed with toner particles so as to be 10.0 parts by mass and 30.0 parts by mass, respectively, and these are used as samples for a calibration curve.

  In the case of silica fine particles, the silica fine particles are mixed with the toner particles so as to be 0.1 parts by weight, 1.0 part by weight, and 2.5 parts by weight with respect to 100 parts by weight of the toner particles, and these are used for the calibration curve. This sample.

  For each sample, the above-mentioned tablet molding compressor was used to prepare a sample pellet for a calibration curve as described above, and observation was made at a diffraction angle (2θ) = 109.08 ° when PET was used as a spectroscopic crystal. The counting rate (unit: cps) of the Si-Kα ray to be measured is measured. At this time, the acceleration voltage and current value of the X-ray generator are 24 kV and 100 mA, respectively. A calibration curve of a linear function is obtained with the X-ray count rate obtained as the vertical axis and the amount of aluminum fine particles or silica fine particles in each calibration curve sample as the horizontal axis.

  Next, using the tablet molding compressor, the toner to be analyzed is formed into pellets as described above, and the counting rate of the Si-Kα rays is measured. Then, the content of aluminum fine particles or silica fine particles in the toner particles is calculated from the calibration curve.

<Measurement of melting point of wax>
The melting point of the wax is the peak temperature of the maximum endothermic peak in the DSC curve measured according to ASTM D3418-82 using a differential scanning calorimeter (trade name: Q2000, manufactured by TA Instruments).

  For the temperature correction of the device detection unit, the melting points of indium and zinc are used, and for the correction of the amount of heat, the heat of fusion of indium is used. Specifically, about 2 mg of a sample is precisely weighed, placed in an aluminum pan, an empty aluminum pan is used as a reference, and the rate of temperature rise is between a measurement temperature range of 30 ° C. and 200 ° C. The measurement is performed at 10 ° C / min. In the measurement, the temperature is once raised to 200 ° C., subsequently lowered to 30 ° C., and then the temperature is raised again.

  The maximum endothermic peak temperature of the DSC curve in the temperature range of 30 ° C. to 200 ° C. in the second temperature raising process is defined as the melting point. Here, there is no holding time after the temperature is raised to 200 ° C., and the temperature is lowered to 30 ° C. as soon as 200 ° C. is reached.

<Measurement of weight average particle diameter (D4) of toner>
The weight average particle diameter (D4) of the toner is
Precise particle size distribution measurement device (trade name: Coulter Counter Multisizer3, manufactured by Beckman Coulter, Inc.) equipped with a 100 μm aperture tube by the pore electrical resistance method, and an attached dedicated for setting measurement conditions and analyzing measurement data Software (Brand name: Beckman Coulter Multisizer3 Version 3.51, manufactured by Beckman Coulter)
, Measure with 25,000 effective measurement channels, analyze the measurement data, and calculate. As the electrolytic aqueous solution used for the measurement, a special grade sodium chloride is dissolved in deionized water to a concentration of about 1% by mass, specifically, “ISOTON II” (manufactured by Beckman Coulter) is used. .

  Before performing measurement and analysis, set the dedicated software as follows.

  In the “Standard Measurement Method (SOM) Change Screen” of the dedicated software, set the total count in the control mode to 50000 particles, set the number of measurements to 1 and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter Set the value obtained using The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. In addition, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is checked. In the “pulse to particle size conversion setting screen” of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.

  Specific measurement methods are as follows (1) to (7).

  (1) About 200 mL of the above electrolytic solution is placed in a 250 mL round bottom beaker made exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rpm. The dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the analysis software.

  (2) About 30 mL of the electrolytic aqueous solution is placed in a glass 100 mL flat-bottomed beaker, and about 0.3 mL of a diluted solution obtained by diluting the above-mentioned “Contaminone N” with deionized water 3 times as a dispersant is added thereto. Add.

  (3) A predetermined amount of deionized water is placed in a water tank of an ultrasonic disperser (trade name: Ultrasonic Dispersion System Tetora 150) (manufactured by Nikka Ki Bios Co., Ltd.), and the above “Contaminone N” is placed in this water tank. The ultrasonic disperser includes two oscillators with an oscillation frequency of 50 kHz with a phase shifted by 180 degrees and an electrical output of 120 W.

  (4) The beaker of (2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.

  (5) In a state where the electrolytic aqueous solution in the beaker of (4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Furthermore, the ultrasonic dispersion process is continued for 60 seconds. In ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.

  (6) In the round bottom beaker of the above (1) installed in the sample stand, the electrolyte aqueous solution of the above (5) in which the toner is dispersed using a pipette is dropped, so that the measured concentration becomes about 5%. adjust. The measurement is performed until the number of measured particles reaches 50,000.

  (7) The measurement data is analyzed with the dedicated software attached to the apparatus, and the volume average particle diameter (D4) is calculated. The “average diameter” on the analysis / volume statistics (arithmetic average) screen when the graph / volume% is set with the dedicated software is the weight average particle diameter (D4).

<Measuring method of average circularity of toner>
The average circularity of the toner is measured by a flow type particle image analyzer (trade name: FPIA-3000, manufactured by Sysmex Corporation) under the measurement and analysis conditions during the calibration operation.

  The measurement principle of the flow-type particle image analyzer is to capture flowing particles as a still image and perform image analysis. The sample added to the sample chamber is fed into the flat sheath flow cell by a sample suction syringe. The sample fed into the flat sheath flow is sandwiched between sheath liquids to form a flat flow. The sample passing through the flat sheath flow cell is irradiated with strobe light at 1/60 second intervals, and the flowing particles can be photographed as a still image. Further, since the flow is flat, the image is taken in a focused state. The particle image is picked up by a CCD camera, and the picked-up image is image-processed at an image processing resolution of 512 × 512 pixels (0.37 μm × 0.37 μm per pixel), the contour of each particle image is extracted, and the particle image The projected area S, the peripheral length L, etc. are measured.

  Next, the equivalent circle diameter and the circularity are obtained using the area S and the peripheral length L. The equivalent circle diameter is the diameter of a circle having the same area as the projected area of the particle image, and the circularity C is a value obtained by dividing the circumference of the circle obtained from the equivalent circle diameter by the circumference of the projected particle image. And is calculated by the following formula.

Circularity C = 2 × (π × S) 1/2 / L
When the particle image is circular, the degree of circularity is 1.000, and as the degree of irregularities on the outer periphery of the particle image increases, the degree of circularity decreases. After calculating the circularity of each particle, the range of the circularity of 0.200 to 1.000 is divided into 800, the arithmetic average value of the obtained circularity is calculated, and the value is defined as the average circularity.

  The specific measurement method is as follows.

  First, about 20 mL of ion-exchanged water from which impure solids are removed in advance is put in a glass container. About 0.2 mL of a diluted solution obtained by diluting the above-mentioned “Contaminone N” about 3 times by mass with ion-exchange water is added as a dispersant. Further, about 0.02 g of a measurement sample is added, and a dispersion treatment is performed for 2 minutes using an ultrasonic disperser to obtain a dispersion for measurement. In that case, it cools suitably so that the temperature of a dispersion liquid may become 10 to 40 degreeC. As the ultrasonic disperser, a desktop type ultrasonic cleaner disperser (trade name: VS-150, manufactured by Vervocrea) having an oscillation frequency of 50 kHz and an electric output of 150 W was used. A predetermined amount of ion-exchanged water is placed in the water tank, and about 2 mL of the above “Contaminone N” is added to the water tank.

  For the measurement, the above-mentioned flow type particle image analyzer equipped with a standard objective lens (10 times) was used, and a particle sheath (trade name: PSE-900A, manufactured by Sysmex Corporation) was used as the sheath liquid. The dispersion prepared according to the above procedure is introduced into the flow particle image analyzer, and 3000 toner particles are measured in the total count mode in the HPF measurement mode. Then, by setting the binarization threshold at the time of particle analysis to 85% and specifying the analysis particle diameter, the number ratio (%) of particles in the range and the average circularity are calculated. The average circularity of the toner was set to an equivalent circle diameter of 1.98 μm to 39.96 μm, and the average circularity of the toner was determined.

  In measurement, automatic focus adjustment is performed using standard latex particles (specifically, “RESEARCH AND TEST PARTICLES Latex Microsphere Suspensions 5200A” manufactured by Duke Scientific, Inc. is diluted with ion-exchanged water). Thereafter, it is preferable to perform focus adjustment every two hours from the start of measurement.

  In the following examples, a flow-type particle image analyzer that has been calibrated by Sysmex Corporation and has received a calibration certificate issued by Sysmex Corporation was used. The measurement was performed under the measurement and analysis conditions when the calibration certificate was received, except that the analysis particle diameter was limited to a circle equivalent diameter of 1.98 μm or more and less than 39.69 μm.

  Hereinafter, based on an Example, this invention is demonstrated more concretely.

<Example of production of aluminum fine particles 1-7>
High brightness grade flaky aluminum paste 574PS (metal content: 75.0%, number average particle size: 13 μm) manufactured by Showa Aluminum Powder Co., Ltd. was crushed by a ball mill using glass beads. In this way, aluminum fine particles 1 to 7 (bright colorant) having an average D _{50n of} major axis and an aspect ratio (major axis / minor axis) shown in Table 1 were obtained.

<Production example of titania fine particles>
An ilmenite ore containing 50% by mass of TiO ₂ equivalent was dried at 150 ° C. for 3 hours and then dissolved by adding sulfuric acid to obtain an aqueous solution of TiOSO ₄ .

After concentrating the obtained aqueous solution, 8 parts by mass of titania sol having rutile crystals was added as a seed, followed by hydrolysis at 150 ° C. to obtain a slurry of TiO (OH) ₂ containing impurities.

This slurry was repeatedly washed with water having a pH of 5 to 6 to sufficiently remove sulfuric acid, FeSO ₄ and impurities, thereby obtaining a slurry of high-purity metatitanic acid [TiO (OH) ₂ ].

After filtering this slurry, 0.5 parts by mass of lithium carbonate (Li ₂ CO ₃ ) is added and baked at 320 ° C. for 5 hours, and then repeatedly pulverized by a jet mill to form primary particles having rutile crystals. Titania fine particles (bright colorant) having a number average particle diameter of 70 nm were obtained.

<Production Example of Silica Fine Particle 1>
Silica fine particles to be contained (internally added) in the toner particles were produced by a combustion method using hexamethylcyclotrisiloxane as a raw material. As the combustion furnace, a hydrocarbon-oxygen mixed burner having a double tube structure capable of forming an inner flame and an outer flame was used. A two-fluid nozzle for slurry injection was grounded at the center of the burner, and a silicon compound as a raw material was introduced. A hydrocarbon-oxygen flammable gas was injected from around the two-fluid nozzle to form an inner flame and an outer flame, which are reducing atmospheres. The atmosphere, temperature, flame length, etc. were adjusted by controlling the amount and flow rate of combustible gas and oxygen. Silica fine particles were formed from the silicon compound in the flame, and further fused to a desired particle size. And after cooling, the silica raw material was obtained by collecting with a bag filter etc.

  The obtained silica base material 99.5% by mass was subjected to surface treatment with 0.5% by mass of hexamethyldisilazane to obtain silica fine particles 1 to be contained (internally added) in the toner particles. The number average particle diameter of primary particles of the obtained silica fine particle 1 was 110 nm.

<Production example of silica fine particles 2 to 7>
The toner particles were prepared in the same manner as the silica fine particles 1 except that the number average particle diameter of the silica raw material was changed as shown in Table 2 by changing the amounts and flow rates of the combustible gas and oxygen. Silica fine particles 2 to 7 contained (added internally) were obtained.

[Production Example of Polyester Resin L]
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 72.0 parts by mass (0.20 mol, 100.0 mol% with respect to the total number of polyhydric alcohols)
-Terephthalic acid: 28.0 parts by mass (0.17 mol, 96.0 mol% based on the total number of moles of polycarboxylic acid)
-Tin 2-ethylhexanoate (esterification catalyst): 0.5 part by mass The above materials were weighed and placed in a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was performed for 4 hours while stirring at a temperature of 200 ° C.

  Further, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, then cooled to 180 ° C. and returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 1.3 parts by mass (0.01 mol, 4.0 mol% based on the total number of polyvalent carboxylic acids)
-Tert-butylcatechol (polymerization inhibitor): 0.1 mass part Then, the said material was added, the pressure in a reaction tank was lowered | hung to 8.3 kPa, and it was made to react for 1 hour, maintaining the temperature at 180 degreeC. Then, after confirming that the softening point measured according to ASTM D36-86 reached 94 ° C., the temperature was lowered to stop the reaction. In this way, a polyester resin L (binder resin) was obtained (second reaction step).

  The obtained polyester resin L had a softening point (Tm) of 94 ° C. and a glass transition temperature (Tg) of 57 ° C.

[Production Example of Polyester Resin H]
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 72.3 parts by mass (0.20 mol, 100.0 mol% with respect to the total number of polyhydric alcohols)
-Terephthalic acid: 18.3 parts by mass (0.11 mol, 65.0 mol% based on the total number of moles of polycarboxylic acid)
・ Fumaric acid: 2.9 parts by mass (0.03 mol, 15.0 mol% based on the total number of moles of polycarboxylic acid)
-Tin 2-ethylhexanoate (esterification catalyst): 0.5 part by mass The above materials were weighed and placed in a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 2 hours while stirring at a temperature of 200 ° C.

  Further, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, cooled to 180, and returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 6.5 parts by mass (0.03 mol, 20.0 mol% with respect to the total number of polycarboxylic acids)
-Tert-butylcatechol (polymerization inhibitor): 0.1 mass part Then, the said material was added, it was made to react for 15 hours, reducing the pressure in a reaction tank to 8.3 kPa, and maintaining temperature at 160 degreeC. And after confirming that the softening point measured according to ASTM D36-86 reached 132 ° C., the temperature was lowered to stop the reaction. In this way, a polyester resin H (binder resin) was obtained (second reaction step).

  The resulting polyester resin H had a softening point (Tm) of 132 ° C. and a glass transition temperature (Tg) of 61 ° C.

[Example 1]
<Production example of toner 1>
Polyester resin L 75.00 parts by mass Polyester resin H 25.00 parts by mass Fischer-Tropsch wax (peak temperature of maximum endothermic peak: 90 ° C) 5.00 parts by mass Aluminum fine particle 1 (bright colorant) 10.00 Part by mass-Aluminum compound of 3,5-di-t-butylsalicylate 0.50 part by mass-Silica fine particle 1 1.00 part by mass The above materials were mixed with a Henschel mixer (trade name: FM-75 type, manufactured by Mitsui Mining Co., Ltd.) ), And the number of rotations was 20 seconds ⁻¹ and the rotation time was 5 minutes. Then, it knead | mixed with the PCM kneading machine (Brand name: PCM-30 type | mold, Ikegai Co., Ltd.) which set temperature to 125 degreeC. The obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized material. The obtained coarsely crushed material was finely pulverized with a mechanical pulverizer (trade name: T-250, manufactured by Turbo Kogyo Co., Ltd.). Furthermore, classification was performed using a rotary classifier (trade name: 200TSP, manufactured by Hosokawa Micron Corporation) to obtain toner particles. As an operating condition of the rotary classifier, the classifying rotor rotation speed was set to 50.0 sec- ¹ . The obtained toner particles had a weight average particle diameter (D4) of 5.7 μm.

4.5 parts by mass of silica fine particles 1 (as an external additive) are added to 100 parts by mass of the obtained toner particles, and rotated using a Henschel mixer (trade name: FM-75 type, manufactured by Mitsui Mining Co., Ltd.). Mixing was performed under conditions of a number of 30 seconds ^-1 and a rotation time of 10 minutes. The obtained mixture was heat-treated with the surface treatment apparatus shown in FIG. 1 to obtain heat-treated toner particles. The operating condition was a feed amount: 5 kg / hour. Also, hot air temperature C: 220 ° C., hot air flow rate: 6 m ³ / min, cold air temperature E: 5 ° C., cold air flow rate: 4 m ³ / min, cold air absolute moisture content: 3 g / m ³ , blower air flow rate: 20 m ³ / min, The injection air flow rate was 1 m ³ / min.

  The obtained heat-treated toner particles had an average circularity of 0.963 and a weight average particle diameter (D4) of 6.2 μm.

  To 100 parts by mass of the obtained heat-treated toner particles, 0.5 part by mass of titania fine particles (as an external additive) having a primary average particle diameter of 32.0 nm was added. Then, the mixture was mixed for 5 minutes at a peripheral speed of 45 m / sec with a Henschel mixer (FM75 type, manufactured by Mitsui Miike Chemical Co., Ltd.), and passed through an ultrasonic vibration sieve having an aperture of 54 μm to obtain toner 1.

[Examples 2 to 19 and Comparative Examples 1 to 4]
<Production Examples of Toners 2-18 and Comparative Toners 1-4>
As shown in Table 3, toners 2 to 21 and comparative toners 1 to 7 were produced in the same manner as in the toner 1 production example, except that the types and contents of the bright colorant and silica fine particles were changed.

[Example 1]
<Example of production of two-component developer 1>
The toner concentration is 9% by mass.
Toner 1 and
Magnetic ferrite carrier particles (number average particle diameter: 35 μm) having a surface coating layer of silicone resin are used in a V-type mixer (trade name: V-10 type, Tokuju Seisakusho Co., Ltd.), and the rotational speed is 0.00. Two-component developer 1 was obtained by mixing under conditions of 5 seconds ⁻¹ and rotation time: 5 minutes. The two-component developer 1 was used as the two-component developer for Example 1.

[Examples 2 to 19 and Comparative Examples 1 to 4]
<Production Examples of Two-Component Developers 2-19 and Comparative Two-Component Developers 1-4>
The two-component developer 2-19 and the comparative two-component developer 1-4 are changed in the same manner as in the production example of the two-component developer 1, except that the toner 1 is changed to the toner 2-19 and the comparative toner 1-4. Manufactured. Two-component developers 2 to 19 and comparative two-component developers 1 to 4 were used as the two-component developers for Examples 2 to 19 and Comparative Examples 1 to 4, respectively.

[Examples 1 to 19 and Comparative Examples 1 to 4]
<Evaluation of two-component developer 1>
<Evaluation 1> Evaluation of image density stability The two-component developer 1 is placed in the cyan station of a full color copying machine (trade name: image PRESS C800) manufactured by Canon Inc., and the toner of the FFH image (solid portion) is on paper The development conditions were adjusted so that the amount applied to the surface was 1.2 mg / cm ² . The FFH image is a value in which 256 gradations are displayed in hexadecimal notation, and 00H is the first gradation (plain part) and FFH is the 256th gradation (solid part).

  As the evaluation paper, black paper having an image density of 1.5 or more was used.

  The following evaluations 1-1 to 1-3 were performed while replenishing toner 1 as needed.

  The evaluation results are shown in Table 3.

  The image density was measured using an X-Rite color reflection densitometer (trade name: 500 series: manufactured by X-Rite).

(Evaluation 1-1) Evaluation of stability of image density in low temperature and low humidity environment (15 ° C., 10% RH) First, 500 sheets continuous paper feeding test in a low temperature and low humidity environment (15 ° C., 10% RH) ( A4 paper side, printing ratio: 80%).

  During the 500 sheet continuous sheet passing test, the sheet was passed under the same development conditions and transfer conditions (no calibration) as the first sheet.

(Evaluation 1-2) Evaluation of image density stability immediately after changing from a low temperature and low humidity environment (15 ° C., 10% RH) to a high temperature and high humidity environment (30 ° C., 80% RH) After changing from a low temperature and low humidity environment (15 ° C., 10% RH) to a high temperature and high humidity environment (30 ° C., 80% RH) over 8 hours, 500 sheets were continuously passed in the same manner as in Evaluation 1-1. The test was performed (A4 paper side, printing ratio: 80%).

(Evaluation 1-3) Evaluation of stability of image density under high temperature and high humidity environment (30 ° C., 80% RH) Next, the sample was left in a high temperature and high humidity environment (30 ° C., 80% RH) for 8 hours or more. After fully adapting to the use environment, a 500-sheet continuous paper feeding test (A4 paper side, printing ratio: 80%) was performed in the same manner as in Evaluation 1-1.

(Evaluation of stability of image density during 500 sheet continuous paper test)
Measure the image density of all FFH image parts (solid parts) of 500 images output in each environment, and calculate the density difference between the highest density and the lowest density for each environment, As evaluation 1-1 and evaluation 1-3, the following criteria were evaluated as the concentration stability performance under each environment. Moreover, as evaluation 1-2, the environmental fluctuation tracking performance was evaluated according to the following criteria.

  The evaluation results are shown in Table 3.

(Evaluation criteria)
A: Less than 0.05 B: 0.05 or more and less than 0.10 C: 0.10 or more and less than 0.20 D: 0.20 or more <Evaluation 2> Evaluation of Toner Coloring Strength As an electrophotographic image forming apparatus Evaluation was performed by using the modified machine of a full-color copying machine (trade name: image RUNNER ADVANCE C5255) manufactured by Canon Inc. and introducing the two-component developer 1 into the developing unit of the cyan station.

The evaluation environment is a normal temperature and humidity environment (23 ° C., 50% RH), and the evaluation paper is plain paper for copying (product name: GFC-081, A4 paper, basis weight: 81.4 g / m ² , Canon Marketing) Used in Japan).

  First, in a normal temperature and humidity environment, the amount of applied toner on paper was changed, and the relationship between the image density and the amount of applied toner on the paper was examined.

  Next, the image density of the FFH image (solid portion) was adjusted to be 0.40, and the amount of applied toner when the image density became 0.40 was obtained.

From the applied toner amount (mg / cm ² ), the coloring power of the toner was evaluated according to the following criteria.

  The evaluation results are shown in Table 3.

(Evaluation criteria)
A: Less than 0.35 B: 0.35 or more and less than 0.50 C: 0.50 or more and less than 0.65 D: 0.65 or more <Evaluation 3> Evaluation of Brightness of Toner The above image density is 0.40. Using the FFH image (solid portion), the ratio (A / B) of the reflectance A at a light receiving angle of + 30 ° and the reflectance B at a light receiving angle of −30 ° with respect to incident light at an incident angle of −45 ° was calculated. As the variable angle photometer, a spectroscopic variable angle color difference meter (trade name: GC5000L) manufactured by Nippon Denshoku Industries Co., Ltd. was used, and the wavelength was set to 470 nm.

  The evaluation results are shown in Table 3.

(Evaluation criteria)
A: A / B is 70 or more and less than 80 B: A / B is 55 or more and less than 70 C: A / B is 40 or more and less than 55 D: A / B is less than 40 <Evaluation 4> Evaluation of fine line reproducibility Fine line reproducibility The evaluation is based on an image (print ratio: 4%) in which a grid pattern with a line width of 3 pixels is printed on the entire surface of A4 paper after outputting 500 images in a high temperature and high humidity environment (30 ° C., 80% RH). The reproducibility was evaluated by the following evaluation criteria. The line width of 3 pixels is theoretically 127 μm. The line width of the image was measured with a microscope VK-8500 (manufactured by Keyence Corporation). The line width was measured by randomly selecting 5 points, and the following L was defined as the fine line reproducibility index when the average value of 3 points excluding the minimum and maximum values was d (μm).

L (μm) = | 127−d |
L defines a difference between a theoretical line width of 127 μm and a line width d on the output image. Since d may be greater than 127 or smaller than d, it is defined as the absolute value of the difference. Smaller L indicates better fine line reproducibility.

  The evaluation results are shown in Table 3.

(Evaluation criteria)
A: L is 0 μm or more and less than 10 μm B: L is 10 μm or more and less than 15 μm C: L is 15 μm or more and less than 20 μm D: L is 20 μm or more <Evaluation of Two-Component Developer 2-18 and Comparative Two-Component Developers 1-4>
The two-component developer was evaluated in the same manner as the evaluation of the two-component developer 1 except that the two-component developer 1 was changed to the two-component developers 2 to 19 and the comparative two-component developers 1 to 4.

  The evaluation results are shown in Table 3.

DESCRIPTION OF SYMBOLS 1 Raw material fixed supply means 2 Compressed gas flow rate adjustment means 3 Introducing pipe 4 Protruding member 5 Supply pipe 6 Processing chamber 7 Hot air supply means 8 Cold air supply means 9 Control means 10 Recovery means 11 Hot air supply means outlet 12 Distribution member 13 Turning member 14 Powder particle supply port

Claims (3)

A toner having toner particles containing a binder resin, aluminum fine particles and silica fine particles,
The toner particles have a weight average particle diameter (D4) of 3.0 μm or more and 10.0 μm,
The toner particles contain the aluminum fine particles and the silica fine particles in an inner region of 0.3 μm or more from the surface of the toner particles,
The content of the aluminum fine particles in the toner particles is 5.0 parts by mass or more and 30.0 parts by mass or less with respect to 100 parts by mass of the toner particles.
The toner, wherein the content of the silica fine particles in the toner particles is 0.1 parts by mass or more and 2.5 parts by mass with respect to 100 parts by mass of the toner particles. 2. The toner according to claim 1, wherein an average aspect ratio (major axis / minor axis) of the aluminum fine particles is 1.2 or more and 15 or less, and an average major axis D _50n of the aluminum fine particles is 200 nm or more and 400 nm or less. The average aspect ratio (major axis / minor axis) of the silica fine particles is 1.0 or more and 1.2 or less, and the average major axis D _50n of the silica fine particles is 30 nm or more and 200 nm or less. The toner described.

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