JP2018097154A - Toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce deviation in image density between an image output before being left standing for a long time in a high-humidity environment and an image output after being left standing for a long time.SOLUTION: A toner includes toner particles containing a binder resin and a colorant. The toner particles each have inorganic fine particles on its surface; the inorganic fine particles each have a compound having a dendrimer structure on its surface; the compound having a dendrimer structure has a silyl group represented by formula (1). In the formula, R, Rand Ris an alkyl group having 1 to 8 carbon atoms.SELECTED DRAWING: None

Description

  The present invention relates to a toner used in an electrophotographic system, an electrostatic recording system, an electrostatic printing system, and a toner jet system.

  In recent years, as electrophotographic copying machines and printers are widely used, freedom of image output media such as thick paper and thin paper, high-speed printing, and energy saving are required. Electrophotographic copying machines and printers consume a large amount of energy when fixing toner to paper. From this point of view, the electrostatic charge developing toner used for electrophotographic image formation is made of a material that improves the fixing performance to paper. Research and development is actively conducted.

However, as the direction of the resin design of the toner for improving the fixing performance at low energy, the resin material design that is easy to soften at low temperature, for example, lowering the molecular weight of the toner binder resin, the toner fluidity, Releasability and durability tend to decrease.
Various attempts have been made to deal with such problems.
Patent Document 1 discloses a technique for improving low-temperature fixability while maintaining durability and high-temperature offset resistance during fixing by adding a crystalline resin to a toner.
Patent Document 2 discloses a technique for improving fluidity and releasability by adding a vinyl resin having a carbosiloxane dendrimer in a side chain to a toner.

  On the other hand, there are increasing opportunities for copying and printing in various environments around the world. For example, it may be used in a high-temperature and high-humidity environment such as a tropical region or a low-temperature and low-humidity environment such as a cold region. Even in an environment where the temperature and humidity differ greatly, an image output with stable performance is required regardless of the environment. The toner used for electrophotographic image formation is easily influenced by temperature and humidity in terms of quality and performance, and development of a material with little change in performance with respect to the change in temperature and humidity is demanded.

  In particular, moisture present in the air in a high humidity environment has a great influence on the charging performance of the toner. When the toner is left in a high humidity environment for a long time, the charge amount is greatly attenuated. Therefore, the image density of an image output immediately after being left in a high humidity environment for a long time changes greatly compared with that before the storage. There is a problem. With the progress of toner resin design in the direction of improving the low-temperature fixability of toner, there is a large room for improvement on this problem.

JP 2015-45719 A JP 2000-181132 A

A major factor that reduces the charge amount of the toner in a high humidity environment is that moisture in the air is adsorbed on the surface of the charged toner, and an ionic substance dissolves in this moisture to reduce the electrical resistance. That is, the charged charge leaks to the air and to the contact object.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a toner that is capable of forming an image with a stable image density, in which the charge amount hardly changes even when left in a high humidity environment for a long time. To do.

Therefore, the present invention provides
A toner having toner particles containing a binder resin and a colorant,
The toner particles have inorganic fine particles on the surface,
The inorganic fine particles have a compound having a dendrimer structure on the surface,
The compound having a dendrimer structure is intended to provide a toner having a silyl group represented by the following formula (1).

（式中、Ｒ^１、Ｒ^２およびＲ^３は炭素原子数１〜８のアルキル基である。）

(In the formula, R ¹ , R ² and R ³ are alkyl groups having 1 to 8 carbon atoms.)

  According to the present invention, it is possible to provide a toner that has the same chargeability and fine line reproducibility as that before standing even after being left standing for a long time in a high humidity environment and is less likely to contaminate the inside of the developing device. it can.

It is a figure for demonstrating a dendrimer structure. It is a figure of the thermal spheronization processing apparatus used for the Example which concerns on this invention.

  The toner according to the present invention has toner particles containing a binder resin and a colorant. The toner particles have inorganic fine particles on the surface. The inorganic fine particles have a compound having a dendrimer structure on the surface. The compound having a dendrimer structure has a silyl group represented by the formula (1). Details are described below.

<Inorganic fine particles>
In the toner according to the present invention, inorganic fine particles are added (externally added) to the surface of the toner particles in order to control fluidity, adhesion force and chargeability.
Examples of the inorganic fine particles in the present invention include the following. Silicon oxide particles, aluminum oxide particles, titanium oxide particles, magnesium oxide particles, tin oxide particles, zinc oxide particles, cerium oxide particles, zirconium oxide particles, magnesium titanate particles, strontium titanate particles, calcium titanate particles, strontium zirconate Fine particles, calcium zirconate fine particles, magnesium carbonate fine particles, calcium carbonate fine particles, silicon nitride fine particles, boron nitride fine particles, silicon carbide fine particles, montmorillonite fine particles, mica fine particles, hydrotalcite fine particles, forsterite fine particles, talc fine particles, silicone resin fine particles, stearin Fatty acid metal salt fine particles such as zinc acid, and composites of these compositions. Among these, the following are preferable. Metal oxide fine particles such as silicon oxide fine particles, aluminum oxide fine particles, titanium oxide fine particles, magnesium oxide fine particles, tin oxide fine particles, zinc oxide fine particles, zirconium oxide fine particles, calcium titanate fine particles, and strontium titanate fine particles. Particularly preferred are silicon oxide fine particles, aluminum oxide fine particles, and magnesium oxide fine particles.

In order to maintain the charge of the inorganic fine particles, the volume resistivity of the inorganic fine particles is preferably 1 × 10 ⁸ [Ω · cm] or more. The volume resistivity of the inorganic fine particles is measured by using a powder resistance measurement system (manufactured by Mitsubishi Chemical Analytech Co., Ltd., MCP-PD51 type) at a pressure of 25 nN / cm ² so that the sample thickness becomes 1 mm. To do.
The number average particle diameter of the primary particles of the inorganic fine particles is preferably 30 nm or more and 300 nm or less. When the number average particle diameter of the primary particles is 30 nm or more, even when the toner is repeatedly used and the toner is subjected to a mechanical load, the convex portion due to the inorganic fine particles can be maintained on the surface of the toner, and an opportunity for frictional charging can be obtained. Hard to lose. Further, when the number average particle diameter of the primary particles is 300 nm or less, the inorganic fine particles are hardly detached from the surface of the toner particles, and the effect of the present invention can be easily maintained.

  The inorganic fine particles have a compound having a dendrimer structure on the surface of the inorganic fine particles, and the compound having a dendrimer structure has a silyl group represented by the formula (1). The silyl group represented by the formula (1) has hydrophobicity. For this reason, even in a high humidity environment, the inorganic fine particles and the vicinity of the inorganic fine particles hold the charged charges and maintain the charge amount of the toner.

  The compound having a dendrimer structure preferably has a silyl group represented by the following formula (2).

（式中、Ｒ^４、Ｒ^５およびＲ^６は炭素原子数１〜８のアルキル基である。）

(In the formula, R ⁴ , R ⁵ and R ⁶ are alkyl groups having 1 to 8 carbon atoms.)

The dendrimer structure means a structure in which a branch unit is coupled to one central unit as shown in FIG. 1 and is radially and regularly branched from the central unit. The first branch unit counted from the central unit is called the first generation, the second branch unit is called the second generation,..., And the nth branch unit is called the nth generation.
An example of the dendrimer structure is shown in the following formula (3).

  The above formula (3) is a molecular structure in which a branch unit having the same structure is bonded to the silicon atom at the center and spreads in a spherical or hemispherical shape. By adopting such a dendrimer structure, a function higher than conventional or an unprecedented function is expressed. In the compound having a dendrimer structure, the functional group at the branch end is regularly arranged outwardly, so that the properties of the functional group present at the branch end are particularly easily enhanced.

  The compound having a dendrimer structure used in the present invention has a hydrophobic silyl group, and more preferably, the silyl group is present at the branched end. Furthermore, the number of silyl groups per molecule of a compound having a dendrimer structure is preferably 6 or more.

The central unit of the dendrimer structure is not particularly limited, but a silicon atom is preferable from the viewpoint of chargeability.
The branch unit is not particularly limited, but similarly, a unit having a siloxane bond is preferred from the viewpoint of chargeability (siloxane dendrimer). Furthermore, for the purpose of increasing the hydrophobicity of the entire dendrimer, a unit (carbosiloxane dendrimer) in which a hydrocarbon is linked to a siloxane bond is more preferable. The number of branch unit generations having a dendrimer structure can be appropriately selected according to the size of the inorganic fine particles used, but the first to third generations are preferred.

  In the present invention, the bulky dendrimer structure has high hydrophobicity, thereby giving the inorganic fine particles the ability to suppress the adsorption of moisture in the air to the inorganic fine particles themselves and the vicinity thereof, and charging the surface of the toner. Attenuation and leakage of charges at the site can be suppressed.

  The compound having a dendrimer structure according to the present invention is preferably a siloxane dendrimer having a silyl group represented by the following formula (4).

（式中、Ｒ^７およびＲ^８は炭素原子数１〜８のアルキル基である。Ｚ^１はｉ＝１とした場合に次の式（５）で示される基である。 ）

(In the formula, R ⁷ and R ⁸ are alkyl groups having 1 to 8 carbon atoms. Z ¹ is a group represented by the following formula (5) when i = 1.)

(R ⁹ is an alkylene group having 1 to 8 carbon atoms, R ¹⁰ and R ¹¹ are alkyl groups having 1 to 8 carbon atoms. Z ^{i + 1} is an alkyl group having 1 to 8 carbon atoms, and the formula (5 A is 0 or 1. i is an integer of 1 to 5 indicating the generation of the silylalkyl group, provided that i = b. , Z ^{i + 1} is an alkyl group having 1 to 8 carbon atoms, and when i <b, the group is represented by the formula (5), and b is a dendrimer structure containing the group represented by the formula (5). An integer from 1 to 5 indicating the generation of the outermost branching unit of the compound having

The siloxane dendrimer having the above structure has a chemical structure that is highly branched radially from one silicon atom, and the generation number of the outermost branch unit indicates the degree of branching. For example, when the generation number of the outermost branch unit is 1, a = 1, and Z ^{i + 1} is a methyl group, the silyl group is represented by the following formula (6).

（式中、Ｒ^７、Ｒ^８、Ｒ^１０およびＲ^１１は炭素原子数１〜８のアルキル基である。Ｒ^９は炭素数１〜８のアルキレン基である。）

(In the formula, R ⁷ , R ⁸ , R ¹⁰ and R ¹¹ are alkyl groups having 1 to 8 carbon atoms. R ⁹ is an alkylene group having 1 to 8 carbon atoms.)

Similarly, when the generation number of the outermost branch unit is 2, a = 1, and Z ^{i + 1} is a methyl group, the silyl group is represented by the following formula (7).

（式中、Ｒ^７、Ｒ^８、Ｒ^１０およびＲ^１１は炭素原子数１〜８のアルキル基である。Ｒ^９は炭素数１〜８のアルキレン基である。）
本発明に係るデンドリマー構造を有する化合物は、以下の式（８）で示される構造であることが好ましい。

(In the formula, R ⁷ , R ⁸ , R ¹⁰ and R ¹¹ are alkyl groups having 1 to 8 carbon atoms. R ⁹ is an alkylene group having 1 to 8 carbon atoms.)
The compound having a dendrimer structure according to the present invention preferably has a structure represented by the following formula (8).

(Wherein R ¹ , R ² , and R ³ are each an alkyl group having 1 to 8 carbon atoms or an aryl group, n is the number of branched silyl groups, and X is a dendrimer central unit. This is a dendrimer main skeleton combined with branched units, Y is a unit having a polar group, specifically, an alkoxy group, a hydroxyl group, an amino group, a carboxylic acid and its salt, phosphoric acid and its salt, sulfonic acid and its (Salts are preferred. In the case of an alkoxy group, it is preferably derived into a hydroxyl group by hydrolysis.)

  Examples of the compound having a dendrimer structure used in the present invention include the following compounds.

  The compound having a dendrimer structure is preferably present on the surface of the inorganic fine particles by being adsorbed on the surface of the inorganic fine particles or by reacting with a functional group on the surface of the inorganic fine particles. When the polar base portion of the compound having a dendrimer structure adheres to the surface of the inorganic fine particle having polarity, the surface of the inorganic fine particle is easily coated with the silyl group portion of the dendrimer structure facing outward from the center of the inorganic fine particle. For example, the polar functional group possessed by the dendrimer and the functional group (for example, OH group portion) present on the surface of the inorganic fine particles can be bound or adsorbed. The polar group bonded to the siloxane dendrimer structure can be conveniently selected according to the polar group and surface potential of the inorganic fine particles to be surface-treated or the production method.

  As a method for surface-treating the surface of the inorganic fine particles with the compound having the dendrimer structure, a known particle surface treatment method can be used. For example, a dry processing method of spraying a solvent in which a compound having a dendrimer structure is dissolved in inorganic fine particles that are stirred and fluidized in a mixer, or a solvent in which the compound having a dendrimer structure is dissolved in a dispersion slurry of inorganic fine particles. There is a wet processing method of adding and stirring.

  The amount of the compound having a dendrimer structure may be appropriately adjusted according to the specific surface area of the inorganic fine particles to be used, but is preferably 0.1 to 100 parts by weight with respect to 100 parts by weight of the inorganic fine particles to be used. -50 mass parts is more preferable.

  The amount of the inorganic fine particles added is preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the toner particles. Further, it is preferable to adjust the toner particle diameter and the inorganic fine particle diameter so that the surface of the toner particles is covered with 5 to 80 area% of the inorganic fine particles.

  Further, the inorganic fine particles are preferably fixed in such a manner that a part of the inorganic fine particles are embedded in the surface of the toner particles. A toner in which inorganic fine particles are embedded and a compound having a dendrimer structure is in close contact with the surface of the toner particles to cover the surface of the toner particles, and when the toner is allowed to stand for a long period of time in a high temperature environment, the toner is easily collected and released. It is possible to suppress the phenomenon of oozing to the surface of the film. This makes it possible to prevent wax contamination of the member in contact with the toner, in particular the carrier in the developing unit and the developing roller, and the toner chargeability and the adhesive force between the member in the developing unit and the toner hardly change, so the image density changes. Hateful. When the inorganic fine particles are embedded and fixed on the surface of the toner, the number average particle diameter of the inorganic fine particles is preferably 30 nm or more and 300 nm or less.

  The state in which the inorganic fine particles are embedded in the surface of the toner particles is enlarged 80,000 times using a FE-SEM (trade name S-4800) manufactured by Hitachi, Ltd., and the surface contour portion of the toner particles is observed. You can confirm by doing. FE means field emission (field emission type).

  In addition, if a compound having a highly hydrophobic dendrimer structure is present on the surface of the toner and the amount of silicon atoms bonded to carbon atoms is appropriate, fine line reproducibility can be achieved in a transfer process in a high humidity environment. Good and preferred. Although the mechanism is not clear, the proper abundance ratio of silicon-carbon atoms with high chargeability on the surface of the toner makes the balance between electrostatic adhesion and charge change due to transfer bias appropriate, resulting in high transfer efficiency and low scattering. It is thought that it has become.

The amount of silicon atoms bonded to carbon atoms is measured using an X-ray photoelectron spectroscopy (XPS) analyzer (PHI (registered trademark) 5000 VERSAPROII, manufactured by ULVAC-PHI Co., Ltd.). The toner is placed on the indentation of the sample stage, pressed, worn, and then introduced into the chamber. Measurement is performed under the conditions of X-Ray_setting of 100 μm (beam diameter) 25 W 15 kV, PassEnergy of 58.7 eV, and Step of 0.125 eV. The measurement results are analyzed, and the element abundance ratio (Si (C) is obtained from the peak intensity of 280-290 eV attributed to carbon and the peak intensity of 100.4 eV attributed to Si (C) (after Si peak separation). ) / C). The abundance ratio (Si (C) / C) of carbon atom C detected by surface analysis by X-ray photoelectron spectroscopy (XPS) and silicon atom Si (C) bonded to the carbon atom is 0.05 or more and 0 .30 or less is preferable.
Further, as other external additives, various inorganic oxide fine particles such as silicon oxide, aluminum oxide and titanium oxide, resin fine particles, and those obtained by treating them with other surface treatment agents may be added in combination.

<Toner particles>
The toner according to the present invention has toner particles containing a binder resin and a colorant.
The toner according to the present invention preferably has a weight average particle diameter of 3.0 to 9.0 μm from the viewpoint of fluidity / chargeability and dot / line reproducibility.

  Examples of the resin used for the binder resin of the toner according to the present invention include the following resins. Styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, and homopolymers thereof; styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene -Acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether Styrene copolymers such as copolymers, styrene-vinyl methyl ketone copolymers, styrene-acrylonitrile-indene copolymers; polyvinyl chloride, phenol resins, natural modified phenol resins, natural resin modified maleic resins, acrylic resins , Methacrylic tree , Polyvinyl acetate, silicone resins, polyester resins, polyurethane, polyamide resins, furan resins, epoxy resins, xylene resins, polyvinyl butyral, terpene resins, coumarone - indene resins, and petroleum resins.

  Furthermore, it is preferable to add a resin having crystallinity (crystalline resin) in addition to the binder resin, since the low-temperature fixability is improved. The crystalline resin refers to a resin in which a clear endothermic peak (melting point) is observed in a reversible specific heat change curve of specific heat change measurement by a differential scanning calorimeter. The crystalline resin exhibits crystallinity by having a low Tg portion with high molecular mobility and a portion (for example, a linear alkyl chain) that is easily crystallized in the resin.

  As the colorant used in the present invention, known pigments and dyes can be used alone or in combination. The content of the colorant is preferably 1 to 15 parts by mass and more preferably 3 to 12 parts by mass with respect to 100 parts by mass of the binder resin.

  Examples of the wax used in the toner according to the present invention include the following. Low molecular weight polyethylene, low molecular weight polypropylene, alkylene copolymer, hydrocarbon wax such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax; oxide of hydrocarbon wax such as oxidized polyethylene wax or block copolymer thereof Products: Waxes mainly composed of fatty acid esters such as carnauba wax; Deoxidized part or all of fatty acid esters such as deoxidized carnauba wax. Furthermore, the following are mentioned. Saturated linear fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as brassic acid, eleostearic acid, and parinalic acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvir alcohol, and seryl alcohol , Saturated alcohols such as merisyl alcohol; polyhydric alcohols such as sorbitol; fatty acids such as palmitic acid, stearic acid, behenic acid, and montanic acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, and carnauvir alcohol , Esters with alcohols such as ceryl alcohol, melyl alcohol; fatty acid amides such as linoleic acid amide, oleic acid amide, lauric acid amide; methylenebisstearic acid amide, ethylene Saturated fatty acid bisamides such as scapric acid amide, ethylene bis lauric acid amide, hexamethylene bis stearic acid amide; ethylene bis oleic acid amide, hexamethylene bis oleic acid amide, N, N ′ dioleyl adipic acid amide, N, N 'Unsaturated fatty acid amides such as dioleyl sebacic acid amide; m-xylene bis stearic acid amide, N, N' aromatic bisamides such as distearyl isophthalic acid amide; calcium stearate, calcium laurate, zinc stearate , Aliphatic metal salts such as magnesium stearate (generally called metal soaps); waxes grafted to aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid ; Monoglyceride behenate And methyl ester compounds having hydroxyl groups obtained by hydrogenation of vegetable fats and oils; fatty acids with polyhydric alcohols of the partial ester such as de.

Among these waxes, a hydrocarbon wax such as paraffin wax and Fischer-Tropsch wax, or a fatty acid ester wax such as carnauba wax is preferable from the viewpoint of improving low-temperature fixability and hot offset resistance.
The content of the wax is preferably 1 to 10 parts by mass and more preferably 2 to 8 parts by mass with respect to 100 parts by mass of the binder resin.

  The toner may contain a charge control agent as necessary. As the charge control agent contained in the toner, known ones can be used. In particular, a metal compound of an aromatic carboxylic acid that is colorless, has a high toner charging speed, and can stably maintain a constant charge amount is preferable.

  Examples of the negative charge control agent include the following. A salicylic acid metal compound, a naphthoic acid metal compound, a dicarboxylic acid metal compound, a polymer compound having a sulfonic acid or a carboxylic acid in the side chain, and a polymer compound having a sulfonate or a sulfonate ester compound in the side chain. Polymer type compounds, boron compounds, urea compounds, silicon compounds, calixarenes having a carboxylate or carboxylic acid esterified product in the side chain.

Examples of the positive charge control agent include quaternary ammonium salts, polymer compounds having the quaternary ammonium salt in the side chain, guanidine compounds, and imidazole compounds.
The charge control agent may be added internally or externally to the toner particles. The addition amount of the charge control agent 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 polyester resin.

The toner according to the present invention can be applied to both a one-component developer and a two-component developer. When the toner according to the present invention is used for a two-component developer, the toner and a magnetic carrier are mixed and used.
As the magnetic carrier, metal particles such as iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, chromium, rare earth whose surface is oxidized or unoxidized, alloy particles thereof, oxide particles and ferrite are used. it can.

The coated carrier obtained by coating the surfaces of the magnetic carrier particles with a resin can be particularly preferably used in a developing method in which an AC bias is applied to the developing sleeve. As a coating method, a conventionally known method such as a method in which a coating solution prepared by dissolving or suspending a resin in a solvent is attached to the surface of the magnetic carrier core particle, a method in which the magnetic carrier core particle and the resin particle are mixed, etc. Is applicable.
When a two-component developer is prepared by mixing a toner and a magnetic carrier, the mixing ratio is preferably 2 to 15% by mass, more preferably 4 as the toner concentration in the two-component developer. ~ 13% by weight.

<Manufacturing method>
As a method for producing toner particles, a pulverization method in which a binder resin, a colorant, and wax as necessary is melt-kneaded, the kneaded product is cooled, and pulverized and classified is preferable.
Hereinafter, a toner manufacturing procedure by the pulverization method will be described.

  In the raw material mixing step, as a material constituting the toner particles, for example, a binder resin and a colorant, and, if necessary, other components such as a wax and a charge control agent are weighed and mixed in a predetermined amount and mixed. . Examples of mixing devices include double-con mixers, V-type mixers, drum-type mixers, super mixers (trade name, manufactured by Kawata Co., Ltd.), Henschel mixers (trade name, Nippon Coke Industries, Ltd.), Nauter mixer ( Product name, Hosokawa Micron Corporation), Mechano Hybrid (trade name, manufactured by Nihon Coke Industries Co., Ltd.), and the like.

  Next, the mixed material is melt-kneaded to disperse wax, crystalline polyester, and the like in the binder resin. The kneading discharge temperature is preferably 100 to 170 ° C. In the melt-kneading process, a batch kneader such as a pressure kneader or a Banbury mixer, or a continuous kneader can be used. From the advantage of continuous production, a single-screw or twin-screw extruder has become the mainstream. ing. For example, the following are mentioned. KTK type twin screw extruder (manufactured by Kobe Steel), TEM type twin screw extruder (manufactured by Toshiba Machine Co., Ltd.), PCM kneader (manufactured by Ikekai Co., Ltd.), twin screw extruder (K.C.)・ Kei Co., Ltd., Ko Kneader (Bus Co., Ltd.), Needex (trade name, manufactured by Nihon Coke Industries Co., Ltd.). Furthermore, the resin composition obtained by melt-kneading may be rolled with two rolls or the like and cooled with water or the like in the cooling step. The cooling rate is preferably 1 to 50 ° C./min.

  Next, the cooled product of the resin composition is pulverized to a desired particle size in the pulverization step. In the pulverization step, for example, coarse pulverization is performed with a pulverizer such as a crusher, a hammer mill, or a feather mill, and then further pulverized with a fine pulverizer. Examples of the pulverizer include a kryptron system (trade name, manufactured by Kawasaki Heavy Industries, Ltd.), a super rotor (trade name, manufactured by Nissin Engineering Co., Ltd.), a turbo mill (manufactured by Turbo Industry Co., Ltd.), An air jet type fine pulverizer may be mentioned.

  Thereafter, classification is performed using a classifier or a sieving machine as described below to obtain toner particles. Inertial classification type elbow jet (trade name, manufactured by Nippon Steel & Mining Co., Ltd.), centrifugal force classification type turboplex (registered trademark, manufactured by Hosokawa Micron Corporation), TSP separator (registered trademark, manufactured by Hosokawa Micron Corporation), Faculty (registered trademark, manufactured by Hosokawa Micron Corporation).

Thereafter, external additives such as inorganic fine powder and resin particles are added and mixed (externally added).
As the mixing device, a mixing device having a rotating body having a stirring member and a main casing provided with a space between the stirring member and the stirring member is used. Examples of such a mixing device include the following. Henschel mixer (trade name, manufactured by Nihon Coke Kogyo Co., Ltd.); Super mixer (trade name, manufactured by Kawata Co., Ltd.); Ribocorn (trade name, manufactured by Okawara Seisakusho Co., Ltd.); Nauter Mixer (registered trademark, Hosokawa Micron (trade name) Co., Ltd.), Turbulizer, Cyclomix (registered trademark, manufactured by Hosokawa Micron Corporation); Spiral Pin Mixer (trade name, manufactured by Taiheiyo Kiko Co., Ltd.); Redige Mixer (trade name, manufactured by Matsubo Corporation) , Nobilta (registered trademark, manufactured by Hosokawa Micron Corporation), hybridization system (trade name, manufactured by Nara Machinery Co., Ltd.), etc. In particular, a Henschel mixer (trade name, manufactured by Nippon Coke Kogyo Co., Ltd.) is preferably used in order to uniformly mix and loosen the silica aggregate.

  The mixing apparatus conditions include the processing amount, the stirring shaft rotation speed, the stirring time, the stirring blade shape, the temperature in the tank, etc. In order to achieve the desired toner performance, various physical properties of the toner particles and additives It is appropriately selected in view of the type and the like, and is not particularly limited.

Further, it is preferable that inorganic fine particles surface-treated with a compound having a carbosiloxane dendrimer structure are embedded and fixed on the surface of the toner particles.
Examples of the fixing method include the following methods. A method of externally adding the toner at a temperature close to Tg (glass transition temperature) of the binder resin of the toner when stirring and mixing with the high-speed stirrer. Nobilta (registered trademark, manufactured by Hosokawa Micron Corporation), hybridization system (trade name, manufactured by Nara Machinery Co., Ltd.), etc. how to. A method of adding inorganic fine particles last when forming toner particles in a solvent such as polymerized toner. Among them, the method of performing surface modification treatment with hot air after mixing the inorganic fine particles with the toner particles at a low temperature is preferable because the inorganic fine particles can be fixed uniformly.

A method for fixing inorganic fine particles to the toner surface using hot air will be described.
As a fixing method using hot air, for example, a method using a surface treatment apparatus shown in FIG.

  The mixture quantitatively supplied by the raw material quantitative supply means 1 is guided to the introduction pipe 3 installed on the vertical line of the raw material supply means by the compressed gas adjusted by the compressed gas adjusting means 2. The processing chamber in which the mixture that has passed through the introduction pipe 3 is uniformly dispersed by a conical projection-like member 4 provided at the center of the raw material supply means, and is guided to the radially extending eight-direction supply pipe 5 to perform heat treatment. 6 leads. 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 heat-treated while turning in the processing chamber 6 and then cooled.

Heat for heat-treating the supplied mixture is supplied from the heat supply means 7, distributed by the distribution member 12, and swirling member 13 for swirling hot air causes hot air to swirl into the processing chamber 6 in a spiral manner. Introduced. As the structure, the turning member 13 for turning hot air has a plurality of blades, and the turning of hot air can be controlled by the number and angle of the blades. The hot air supplied into the processing chamber 6 is preferably such that the temperature at the outlet of the hot air supply means 7 is higher than the softening point Tm of the toner particles. Hot air is supplied from the hot air supply means outlet 11. Moreover, it is preferable that a hot air flow rate is 2-20 m < ³ > / min.

  Further, 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 cooled heat-treated toner particles are recovered by the recovery means 10 at the lower end of the processing chamber 6. In addition, a blower (not shown) is provided at the tip of the collecting means, and is thereby configured to be 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. It is provided in the outer peripheral part of the process chamber 6 so that the turning direction may be maintained. 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 cool air supplied from the cool air supplying means, and the swirling direction of the hot air supplied from the hot air supplying means 7 are all the same direction. Therefore, turbulent flow does not occur in the processing chamber 6, the swirl 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. Heat-treated toner particles with a small amount can be obtained.
Thereafter, if necessary, the fine particles may be externally added again by the apparatus described above.

  The present invention will be described below with reference to examples and comparative examples. In addition, the number average particle size of the particles in the following description is selected by randomly selecting 200 particles with a scanning electron microscope (SEM, S-4800) and adopting the number average value. did.

<Example of production of inorganic fine particles>
<Inorganic fine particles 1>
As a base of inorganic fine particles, 282 g of silicon oxide fine particles having a number average particle diameter of 100 nm and having OH groups on the surface were prepared. Thereafter, 282 g of silicon oxide fine particles were placed in an autoclave including a double sealed container using an inner cylinder made of polytetrafluoroethylene having an inner volume of 5 L and an outer cylinder made of pressure-resistant stainless steel. After replacing the inside of the autoclave with nitrogen gas, the following surface treatment liquid and 18 mL of water are atomized with a two-fluid nozzle while rotating the stirring blade attached to the autoclave at 400 rpm in an atmosphere at a temperature of 60 ° C. The fine particles were sprayed uniformly.
Surface treatment liquid: Surface treatment liquid in which 18.0 g of the compound 1 having the dendrimer structure represented by the following formula (11) is dispersed and dissolved in 900 mL of a toluene solvent. Spraying of the surface treatment liquid is performed 20 times while removing the volatilized toluene. After stirring for 30 minutes, the autoclave was sealed and heated at 200 ° C. for 4 hours. Subsequently, the system is depressurized in a heated state to remove ammonia and remove residual toluene, and inorganic fine particles 1 surface-treated with a compound 1 having a dendrimer structure (also referred to as dendrimer 1) are used as powder. Obtained.

<Inorganic fine particles 2>
Inorganic fine particles 1 except that compound 2 having a dendrimer structure represented by the following formula (12) (also referred to as dendrimer 2) is used in place of compound 1 having a dendrimer structure represented by formula (11). In the same manner, inorganic fine particles 2 were obtained.

<Inorganic fine particles 3>
Inorganic fine particles 1 except that a compound 3 having a dendrimer structure represented by the following formula (13) (also referred to as a dendrimer 3) is used instead of the compound 1 having a dendrimer structure represented by the formula (11). In the same manner, inorganic fine particles 3 were obtained.

<Inorganic fine particles 4>
As a base of inorganic fine particles, 282 g of silicon oxide fine particles having a number average particle diameter of 100 nm were prepared. 282 g of the silicon oxide fine particles were put in the autoclave. After replacing the inside of the autoclave with nitrogen gas, the following surface treatment liquid is atomized with a two-fluid nozzle and uniformly formed into silicon oxide particles while rotating the stirring blade attached to the autoclave at 400 rpm in an atmosphere of 60 ° C. It sprayed so that it might become.
Surface treatment liquid: A surface treatment liquid in which 18.0 g of compound 4 having a dendrimer structure represented by the following formula (14) is dispersed and dissolved in 900 mL of a toluene solvent.
The surface treatment solution was sprayed 10 times while removing the volatilized toluene. Finally, after stirring for 30 minutes, the autoclave was sealed and heated at 150 ° C. for 2 hours. Subsequently, the system was depressurized in a heated state to remove residual toluene, and inorganic fine particles 4 surface-treated with a compound 4 having a dendrimer structure (also referred to as dendrimer 4) were obtained as a powder.

<Inorganic fine particles 5-13>
Except that the material type and particle diameter of the particles serving as the substrate were changed as shown in Table 1, inorganic fine particles 5 to 13 surface-treated with the compound 4 having a dendrimer structure were obtained in the same manner as the inorganic fine particles 4. At this time, the surface treatment amount of the inorganic fine particles was changed by changing the mass of the particles serving as the substrate according to the type and particle diameter of the particles serving as the substrate. The surface treatment amount is calculated by the following calculation formula.
Surface treatment amount = {(mass of surface treatment agent) / (mass of particles serving as substrate)}

<Inorganic fine particles 14>
As an inorganic fine particle substrate, 225 g of titanium oxide fine particles having a number average particle diameter of 25 nm were prepared. 225 g of the titanium oxide fine particles were put in the autoclave. After replacing the inside of the autoclave with nitrogen gas, the following surface treatment liquid is atomized with a two-fluid nozzle and uniformly formed into silicon oxide particles while rotating the stirring blade attached to the autoclave at 400 rpm in an atmosphere of 60 ° C. It sprayed so that it might become.
Surface treatment liquid: A surface treatment liquid in which 75.0 g of compound 5 having a dendrimer structure represented by the following formula (15) is dispersed and dissolved in 900 mL of a toluene solvent.
The surface treatment solution was sprayed 10 times while removing the volatilized toluene. Finally, after stirring for 30 minutes, the autoclave was sealed and heated at 150 ° C. for 2 hours. Subsequently, the system was depressurized in a heated state to remove residual toluene, and inorganic fine particles 14 surface-treated with a compound 5 having a dendrimer structure (also referred to as dendrimer 5) were obtained as a powder.

<Inorganic fine particles 15> (HMDS treatment)
As a substrate of inorganic fine particles, 270 g of silicon oxide fine particles having a number average particle diameter of 100 nm and having OH groups on the surface were prepared. 270 g of the silicon oxide fine particles were put in the autoclave. After the inside of the autoclave was replaced with nitrogen gas, 30.0 g of HMDS (hexamethyldisilazane) and 3.0 g of water were atomized with a two-fluid nozzle while rotating the stirring blade attached to the autoclave at 400 rpm. The silica powder was sprayed uniformly. After stirring for 1 hour in an atmosphere at a temperature of 200 ° C., the autoclave was sealed and heated at 200 ° C. for 2 hours. Subsequently, the inside of the system was depressurized while being heated to perform deammonia treatment, and inorganic fine particles 15 were obtained.

<Inorganic fine particle 16> (silicone oil treatment)
As a base of inorganic fine particles, 270 g of silicon oxide fine particles having a number average particle diameter of 100 nm were prepared. 270 g of the silicon oxide fine particles were put in the autoclave. After the inside of the autoclave was replaced with nitrogen gas, 30.0 g of polydimethylsiloxane diluted to 30% by mass with hexane was rotated and atomized with a two-fluid nozzle while rotating the stirring blade attached to the autoclave at 400 rpm. The silicon fine particles were sprayed uniformly. After stirring for 1 hour in an atmosphere at a temperature of 200 ° C., the system was reduced in pressure while heated to remove hexane, whereby inorganic fine particles 16 were obtained.

<Inorganic fine particle 17>
As an inorganic fine particle substrate, 300 g of silicon oxide fine particles having a number average particle diameter of 100 nm were prepared. 300 g of the silicon oxide fine particles were placed in a polytetrafluoroethylene inner cylindrical stainless steel autoclave having an internal volume of 5 L. After stirring for 2 hours in an atmosphere at a temperature of 250 ° C. while rotating a stirring blade attached to the autoclave at 400 rpm, inorganic fine particles 17 were obtained.
The produced inorganic fine particles are shown in Table 1.

<Example of toner particle production>
<Resin production example 1>
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 71.9 parts by mass (0.20 mol; 100.0 mol% based on the total number of polyhydric alcohols)
-Terephthalic acid: 26.8 parts by mass (0.16 mol; 96.0 mol% based on the total number of polyvalent carboxylic acids)
・ Titanium tetrabutoxide: 0.6 parts by mass

The above materials were weighed in a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introduction tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised to 200 ° C. while stirring, and the reaction was performed for 6 hours while stirring at a temperature of 200 ° C.
Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then 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 polycarboxylic acids)
Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is continued for 3 hours while maintaining the temperature at 180 ° C. (second reaction step), and the weight average molecular weight (Mw) is 15,000. A polyester resin 1 was obtained.

<Resin production example 2>
1,6-hexanediol:
34.5 parts by mass (0.29 mol; 100.0 mol% based on the total number of moles of polyhydric alcohol)
・ Dodecanedioic acid:
65.5 parts by mass (0.28 mol; 100.0 mol% with respect to the total number of polyvalent carboxylic acids)
The above materials were weighed in a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introduction tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised to 140 ° C. while stirring, and the reaction was carried out for 3 hours while stirring at a temperature of 140 ° C.

-Tin 2-ethylhexanoate: 0.5 part by mass Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is performed for 4 hours while maintaining the temperature at 200 ° C. Obtained.
The obtained resin had crystallinity, and when DSC (differential scanning calorimetry) was performed, it had a clear endothermic peak due to crystal melting.

<Vinyl resin production example 1>
-Polyethylene having one or more unsaturated bonds (Mw: 1,400, Mn: 850, endothermic peak by DSC analysis is 100 ° C) 20 parts by mass-Styrene 59 parts by mass-N-butyl acrylate 18.5 parts by mass・ Acrylonitrile 2.5 parts by mass

  The raw material was placed in an autoclave, and the system was replaced with nitrogen. Then, the temperature was raised to 180 ° C. with stirring and maintained at 180 ° C. A vinyl resin in which 50 parts by mass of a 2% by mass di-tert-butyl peroxide xylene solution was continuously dropped into the system for 5 hours, and after cooling, the solvent was separated and removed, and the copolymer was grafted to polyethylene. A polymer (hereinafter also referred to as vinyl resin 1) was obtained. The obtained vinyl resin 1 has a softening point of 110 ° C. and a glass transition temperature of 64 ° C. The molecular weight of the vinyl resin 1 soluble in THF (tetrahydrofuran) by GPC (gel permeation chromatography) is a weight average molecular weight. They were (Mw) 7,400 and number average molecular weight (Mn) 2,800. A peak corresponding to polyethylene which has one or more unsaturated bonds as a raw material was not observed.

<Vinyl resin production example 2> (carbosiloxane dendrimer-containing resin)
・ Styrene 56.0g
・ N-Butyl acrylate 24.0g
-Silicone compound (methacryloxy group-containing carbosiloxane dendrimer) represented by the following formula (16) 20.0 g
・ Radical polymerization initiator (azobisisobutyronitrile) 0.5g
The mixture of the above raw materials was dropped into 150 g of toluene at a temperature of 80 ° C. over 2 hours in a flask equipped with a stirrer purged with nitrogen. After completion of dropping, the temperature was maintained at 80 ° C. for 6 hours. Subsequently, a part of toluene was removed by heating and stirring under reduced pressure with an aspirator. The obtained reaction mixture was put into a large excess of methanol, stirred, and allowed to stand to separate a precipitate. This precipitate was dried under reduced pressure to obtain 92.3 g of a white solid vinyl resin 2.

<Production Example 1 of Toner Particles>
Polyester resin 1 100 parts by mass Polyester resin 2 5 parts by mass Vinyl-based resin 1 5 parts by mass Hydrocarbon wax (peak temperature of maximum endothermic peak 90 ° C) 5 parts by mass I. Pigment Blue 15: 3 5 parts by mass / aluminum compound of 3,5-di-t-butylsalicylate 0.5 part by mass

The raw materials shown in the above formulation were mixed using a Henschel mixer (FM-75 type, manufactured by Nippon Coke Industries Co., Ltd.).
・ Rotation speed 1,200rpm
-Rotation time 5 minutes Then, it knead | mixed using the biaxial kneader (PCM-30 type | mold, Ikegai Co., Ltd. product).
・ Discharge temperature: 135 ℃
・ Rotation speed: 350rpm
The obtained kneaded product was cooled at a cooling rate of 20 ° C./min, and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely crushed product.
The obtained coarsely crushed material was finely pulverized with a mechanical pulverizer (T-250, manufactured by Turbo Kogyo Co., Ltd.). Further, classification was performed using a rotary classifier (200TSP, manufactured by Hosokawa Micron Corporation) to obtain toner particles A.
The rotation speed of the classification rotor of the rotary classifier was 3,000 rpm. The obtained toner particles A had a weight average particle diameter (D4) of 7.5 μm.

<Toner Particle Production Example 2>
-Vinyl resin 2 70 parts by mass-Polyester resin 1 30 parts by mass-Polyester resin 2 4 parts by mass-Vinyl resin 1 5 parts by mass-Hydrocarbon wax (peak temperature of maximum endothermic peak 90 ° C) 5 parts by mass I. Pigment Blue 15: 3 5 parts by mass. 3,5-di-t-butylsalicylate aluminum compound 0.5 parts by mass

The raw materials indicated in the above recipe were mixed. The mixer, the number of rotations, and the rotation time used for mixing were the same as those in Toner Particle Production Example 1.
Then, it knead | mixed. The kneader used for kneading, the set discharge temperature, and the number of rotations were the same as in toner particle production example 1.
The obtained kneaded product was cooled at a cooling rate of 20 ° C./min, and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely crushed product.
The obtained coarsely crushed material was finely pulverized with a mechanical pulverizer (T-250, manufactured by Turbo Kogyo Co., Ltd.). Furthermore, classification was performed using a rotary classifier (200TSP, manufactured by Hosokawa Micron Corporation) to obtain toner particles B.
The rotation speed of the classification rotor of the rotary classifier was 3,000 rpm. The obtained toner particles B had a weight average particle diameter (D4) of 7.5 μm.

[Example 1]
To 100 parts by mass of toner particles A, 4.0 parts by mass of inorganic fine particles 1 are added, and a Henschel mixer (FM-75 type, manufactured by Nihon Coke Kogyo Co., Ltd.) is used. Minutes at a jacket temperature of 0 ° C. to obtain a mixture.

The obtained mixture was heat-treated with the surface treatment apparatus shown in FIG. The operating conditions of the surface treatment apparatus were as follows.
・ Feed amount = 5 kg / hour ・ Hot air temperature = 135 ° C., Hot air flow rate = 6 m ³ / min ・ Cold air temperature = 0 ° C., Cold air flow rate = 4 m ³ / min, Cold air absolute moisture content = 3 g / m ³ ,
・ Blower air volume = 20 m ³ / min ・ Injection air flow rate = 1 m ³ / min.
In Examples 2 to 21 and Comparative Examples 1 to 3 to be described later, heat treatment using the surface treatment apparatus shown in FIG. 2 was not performed.

  From the SEM observation of the toner particles 1, it was confirmed that the inorganic fine particles on the surface of the toner were buried in the surface of the toner particles, and the convex portions due to the inorganic fine particles were formed on the surface of the toner particles. When 50 inorganic fine particles in the toner outline were observed in detail, an average of ½ of the particle diameter was buried in the surface of the toner particles.

  Further, 1.0 part by mass of the inorganic fine particles 15 is added to 100 parts by mass of the toner particles 1, and the rotation speed is 4000 rpm and the rotation time is 10 minutes with a Henschel mixer (FM-10C type, manufactured by Nippon Coke Industries, Ltd.). Toner 1 was obtained by mixing at a jacket temperature of 10 ° C. The Si (C) / C on the surface of the toner by XPS measurement was 0.12.

[Example 2]
Toner particles 2 were obtained from toner particles A by mixing under the conditions shown in Table 2.
The resulting toner particles 2 had a weight average particle diameter (D4) of 7.4 μm.
From the SEM observation of the toner particles 2, it was confirmed that the inorganic fine particles on the surface of the toner were buried in the surface of the toner particles, and the convex portions due to the inorganic fine particles were formed on the surface of the toner particles. When 50 inorganic fine particles in the toner contour portion were observed in detail, an average of ¼ of the particle diameter was buried in the surface of the toner particles.

  Further, mixing was performed under the conditions shown in Table 3, and toner 2 was obtained from 100 parts by mass of toner particles 2. The Si (C) / C on the surface of the toner by XPS measurement was 0.13.

Example 3
4.0 parts by mass of inorganic fine particles 1 are added to 100 parts by mass of toner particles A, and the gap between the blade and the casing is set to 3 mm with a dry particle compounding device (Nobilta (registered trademark) NOB-130, manufactured by Hosokawa Micron Corporation). Then, toner particles 3 were obtained by mixing under the conditions shown in Table 2.
From the SEM observation of the toner, it was confirmed that the inorganic fine particles on the surface of the toner were buried in the surface of the toner particles, and that convex portions due to the inorganic fine particles were formed on the surface of the toner particles. When 50 inorganic fine particles in the toner contour portion were observed in detail, an average of 1/6 of the particle diameter was buried in the surface of the toner particles.

Further, mixing was performed under the conditions shown in Table 3 to obtain toner 3 from 100 parts by mass of toner particles 3. The Si (C) / C on the surface of the toner by XPS measurement was 0.13.
In Examples 1 to 3, the first mixing and the second mixing were performed. In Examples 4 to 21 and Comparative Examples 1 to 3 described later, mixing was performed only once.

Example 4
4.0 parts by mass of inorganic fine particles 1 and 1.0 part by mass of inorganic fine particles 15 were added to 100 parts by mass of toner particles A. Then, using a Henschel mixer (FM-10C type, manufactured by Nippon Coke Kogyo Co., Ltd.), the toner was mixed at a rotation speed of 4000 rpm, a rotation time of 7 minutes, and a jacket temperature of 10 ° C. The Si (C) / C on the toner surface as measured by XPS was 0.14.

[Examples 5 to 21]
Toners 5 to 21 were obtained in the same manner as in Example 4 except that the types and amounts of the inorganic fine particles were changed as shown in Table 4. Table 4 shows the Si (C) / C of the toner surface by XPS measurement of each toner.

[Comparative Examples 1-3]
Toners 22 to 24 were obtained in the same manner as in Example 4 except that the types of toner particles and the types and amounts of inorganic fine particles were changed as shown in Table 4. Table 4 shows the Si (C) / C of the toner surface by XPS measurement of each toner.
When the toners 4 to 24 were observed with an SEM, the embedding of the inorganic fine particles on the toner surface was not confirmed in any of the toners.

<Evaluation methods and evaluation criteria>
<Chargeability 1 after standing in high humidity environment>
Toner 1 to 24 and resin-coated ferrite carrier coated with polymethyl methacrylate resin and having a number average particle diameter of 50 μm are adjusted so that the toner / carrier mass ratio is 7 to 14% (the toner charge amount is in the range of 20 to 40 μC / g). The two-component developers 1 to 24 mixed in the above were prepared.
Using the produced two-component developers 1 to 24, an image was output in a high humidity environment (temperature 25 ° C./relative humidity 80%) using a full color copying machine imageRUNNER ADVANCE C9075PRO manufactured by Canon Inc.
The output image was a 10 cm wide vertical band image (cyan single color mode. A4 landscape paper), and the cyan reflection density on the paper was adjusted to 1.40.
As the evaluation paper, copy paper GF-C081 (A4, basis weight 81.4 g / m ² , sold by Canon Marketing Japan Inc.) was used.
After that, turn off the power of the main body of the copier, take out the developing device from the main body, and leave it in a high humidity environment (temperature 25 ° C / relative humidity 80%) for 120 hours. The apparatus was returned to the main body and the same image was output again under the same development conditions. The reflection density of the obtained output image was measured for an average value at 9 locations using an X-Rite color reflection densitometer (500 series: manufactured by X-Rite), and the difference in reflection density before and after standing was as follows. It was evaluated according to the criteria. The evaluation results are shown in Table 5.

(Evaluation criteria: difference in reflection density of output image before and after standing)
Rank A: Reflection density difference less than 0.04
Rank B: Reflection density difference 0.04 or more and less than 0.07 Rank C: Reflection density difference 0.07 or more and less than 0.10 Rank D: Reflection density difference 0.10 or more and less than 0.15 Rank E: Reflection density difference 0. 15 or more and less than 0.30 Rank F: Reflection density difference 0.30 or more

<Chargeability 2 after standing in a high humidity environment>
Using the produced two-component developers 1 to 24, an image was output in a high humidity environment (temperature 25 ° C./relative humidity 80%) using a full color copying machine imageRUNNER ADVANCE C9075PRO manufactured by Canon Inc.
First, 1,000 sheets were passed with solid white (printing rate 0%) (the developing device rotated without consuming toner).
Thereafter, the output image was a 10 cm wide vertical band image (cyan monochromatic mode, A4 landscape paper), and the cyan reflection density on the paper was adjusted to 1.40.
As the evaluation paper, the copy paper GF-C081 was used.
After that, turn off the power of the main body of the copier, take out the developing device from the main body, and leave it in a high humidity environment (temperature 25 ° C / relative humidity 80%) for 120 hours. The apparatus was returned to the main body and the same image was output again under the same development conditions. With respect to the reflection density of the obtained output image, the average value at nine locations was measured using the X-Rite color reflection densitometer, and the difference in reflection density before and after standing was evaluated according to the following criteria. The evaluation results are shown in Table 5.

(Evaluation criteria: difference in reflection density of output image before and after standing)
Rank A: Reflection density difference less than 0.04
Rank B: Reflection density difference 0.04 or more and less than 0.07 Rank C: Reflection density difference 0.07 or more and less than 0.10 Rank D: Reflection density difference 0.10 or more and less than 0.15 Rank E: Reflection density difference 0. 15 or more and less than 0.30 Rank F: Reflection density difference 0.30 or more

<Reproducibility of fine lines in high humidity environment>
Using the produced two-component developers 1 to 24, an image was output at 30 ° C./80% relative humidity using a Canon full color copier imageRUNNER ADVANCE C9075PRO.
The output image was an image in which a grid pattern with a line width of 3 pixels was printed on the entire surface of A4 paper (printing area ratio 4%).
As the evaluation paper, the copy paper GF-C081 was used.
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 value and the maximum value was d (μm).

L (μm) = | 127−d |
L is the difference between the theoretical line width of 127 μm and the line width d on the output image. Since d may be larger than 127 or smaller than 127, it is defined as the absolute value of the difference. Smaller L indicates better fine line reproducibility. The reproducibility of fine lines was evaluated according to the following evaluation criteria. The evaluation results are shown in Table 5.

Rank A: L is 0 μm or more and less than 7 μm Rank B: L is 7 μm or more and less than 15 μm Rank C: L is 15 μm or more and less than 30 μm Rank D: L is 30 μm or more

<Contamination resistance of the developer internal member after standing in a high temperature environment>
Using the produced two-component developers 1 to 24, an image was output at 25 ° C./50% relative humidity using a full color copier imageRUNNER ADVANCE C9075PRO manufactured by Canon Inc.
First, after passing 100 sheets with solid white (printing rate 0%) (image output, the developer rotates without consuming toner), the output image is a 10 cm wide vertical band image (cyan single color mode, A4). The paper was adjusted so that the reflection density of cyan on the paper was 1.40.
As the evaluation paper, the copy paper GF-C081 was used.
After that, the power of the copying machine is turned off, and the developing device is taken out from the copying machine main body and left in a constant temperature bath at a temperature of 50 ° C./relative humidity of 15% for 72 hours. And output the same image again. The reflection density of the obtained output image is measured with an X-Rite color reflection densitometer (500 series: manufactured by X-Rite), and the average value is measured at 9 locations and compared with the reflection density before and after standing at high temperature. The following criteria were used for evaluation. The evaluation results are shown in Table 5.

(Evaluation criteria: difference in reflection density of output image before and after standing)
Rank A: Reflection density difference less than 0.04
Rank B: Reflection density difference 0.04 or more and less than 0.07 Rank C: Reflection density difference 0.07 or more and less than 0.10 Rank D: Reflection density difference 0.10 or more and less than 0.15 Rank E: Reflection density difference 0. 15 or more and less than 0.30 Rank F: Reflection density difference 0.30 or more

  As described above, a toner that has been left to stand in a high-humidity environment for a long time by using a toner having inorganic fine particles whose surface is treated with a compound having a dendrimer structure having a silyl group on the surface of the toner particle. Also, the charge amount of the toner can be maintained. As a result, it is possible to output an image having no output image density fluctuation.

1. 1. Raw material quantitative supply means, 2. compressed gas flow rate adjusting means; 3. Introducing pipe, 4. Protruding member, 5. supply pipe, 6. processing chamber; Hot air supply means, 8. Cold air supply means, 9. Regulatory means, 10. Recovery means, 11. 11. Hot air supply means outlet, 12. distribution member; Swivel member, 14. Powder particle supply port

Claims (4)

A toner having toner particles containing a binder resin and a colorant,
The toner particles have inorganic fine particles on the surface,
The inorganic fine particles have a compound having a dendrimer structure on the surface,
The toner having a dendrimer structure having a silyl group represented by the formula (1).

(In the formula, R ¹ , R ² and R ³ are alkyl groups having 1 to 8 carbon atoms.) The toner according to claim 1, wherein the compound having a dendrimer structure has a structure represented by the formula (2).

(In the formula, R ⁴ , R ⁵ and R ⁶ are alkyl groups having 1 to 8 carbon atoms.)   The toner according to claim 1, wherein the inorganic fine particles are particles having a number average particle diameter of 30 nm to 300 nm. The toner has an abundance ratio (Si (C) / C) of carbon atoms C detected by surface analysis by X-ray photoelectron spectroscopy (XPS) to silicon atoms Si (C) bonded to carbon atoms of 0.05. The toner according to claim 1, wherein the toner is 0.30 or less.

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