JP2000122334A - Toner and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize such a method to produce a toner having excellent releasability, anti-offsetting property and low temperature fixability. SOLUTION: A mixture is prepared from an aqueous dispersion of wax particles an aqueous dispersion of binder particles and an aqueous dispersion of a colorant. The wax contains >=20 wt.% ester component and has a penetration of <=4. Subsequently, the was particles, the binder particles and the colorant are heat-fused in the aqueous medium to produce the objective toner containing wax domains whose equivalent circular diameter is 200-500 nm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for visualizing an electrostatic latent image in an image forming method such as an electrophotographic method, an electrostatic printing method, and an electrostatic recording method, and a method for manufacturing the toner.

[0002]

2. Description of the Related Art As a method for forming a visible image from image information, a method via an electrostatic latent image, such as an electrophotographic method, an electrostatic printing method, an electrostatic recording method, etc., is widely used. In one example of an electrophotographic image forming process, an electrostatic image is formed on a photoreceptor by charging and exposure, and the electrostatic image is developed with a developer containing toner to form a toner image. The toner image is transferred to the transfer paper,
It is fixed to form a visible image.

In the fixing step of such an image forming process, formation of a fixed image by a heat roller fixing device is widely performed. However, in the fixing by the heat roller fixing device, a so-called offset development occurs in which a part of the molten toner is transferred and adhered to the surface of the heat roller, and the transferred toner is transferred again to the next transfer paper to stain the image. It's easy to do. In addition, due to recent demands for downsizing and low power consumption of copiers, development of toners capable of fixing at lower temperature than conventional ones is strongly desired. For this reason,
Minimum temperature that can be fixed for toner (minimum fixing temperature)
It is desirable that the range of the maximum temperature at which the offset phenomenon does not occur (the fixing temperature range) be wide. 2. Description of the Related Art Conventionally, as a means for preventing the occurrence of an offset phenomenon, a wax (release agent) is added to a toner to impart releasability to the toner itself.

On the other hand, as a method for producing a toner, a production method based on a polymerization method such as an emulsion polymerization method or a suspension polymerization method has been proposed in place of the conventional kneading and pulverizing method (for example, Japanese Patent Application Laid-Open No. Sho.
JP-A-3-186253, JP-A-63-232749, JP-A-4-51251, JP-A-6-329
947, JP-A-9-50149 and JP-A-9-50
See -146295. In particular, according to the polymerized toner obtained by the emulsion polymerization method, the styrene-acrylic resin, which is a typical binder resin, and the wax are not compatible, and the wax is introduced as a domain into the polymerized toner particles. Is done.
For this reason, the releasability (offset prevention effect) can be exhibited in a wide temperature range as compared with the toner obtained by the kneading / pulverizing method.

[0005] In one example of a method for producing a polymerized toner, an aqueous dispersion of binder particles, an aqueous dispersion of colorant particles, and an aqueous dispersion of wax particles are mixed.
The binder particles, the colorant particles, and the wax particles are thermally fused in an aqueous medium. This makes it possible to prepare an aqueous dispersion of toner particles, and by drying the particles separated from the aqueous dispersion by filtration, toner particles containing wax can be obtained.

However, the average particle size of the wax particles in the stable aqueous dispersion is as small as about 50 to 150 nm, and the polymerized toner into which such small diameter wax particles are introduced has a sufficient release property. Does not.
Therefore, in order to obtain a polymerized toner having good releasability (offset prevention effect), it is desired to increase the particle diameter of wax particles (domains) in the polymerized toner.

[0007]

SUMMARY OF THE INVENTION The present invention has been made based on the above circumstances. A first object of the present invention is to provide a toner having good releasability, and excellent in offset resistance and low-temperature fixability. A second object of the present invention is to provide a toner capable of stably forming a high-quality visible image free from image contamination for a long period of time. A third object of the present invention is to provide a method capable of producing a polymerized toner having good releasability, and excellent in offset resistance and low-temperature fixability.
A fourth object of the present invention is to provide a method for producing a toner capable of forming a wax domain having a large diameter in toner particles.

[0008]

The toner of the present invention is a toner for developing an electrostatic image formed by thermally fusing wax particles, binder particles and colorant particles, wherein the wax particles contain an ester component. It is characterized by comprising a wax domain having a penetration of 4 or less and a wax domain having an equivalent circle diameter of 200 to 500 nm.

The following form is preferable for the toner of the present invention. (1) The melting point of the wax constituting the wax particles is 60 to
Be in the range of 110 ° C. (2) The average particle diameter of the wax particles is in the range of 50 to 150 nm. (3) The wax content is 1 to 20% by weight. (4) The binder resin constituting the binder particles is a styrene- (meth) acrylate copolymer.

The method for producing a toner according to the present invention is a method for producing the above toner (toner according to the present invention), wherein the wax contains an ester component in an amount of 20% by weight or more and has a penetration of 4 or less. Aqueous dispersion of wax particles obtained by emulsifying and dispersing, an aqueous dispersion of binder particles, and an aqueous dispersion of colorant particles are mixed, and the wax particles,
A step of thermally fusing the binder particles and the colorant particles in an aqueous medium.

In the production method of the present invention, the following embodiments are preferred. (1) The melting point of the wax constituting the wax particles is 60 to
Be in the range of 110 ° C. (2) The pH of the aqueous dispersion of wax particles is 8.5 to 13.
Be in the range.

The method for producing a toner according to the present invention is a method for producing the above toner (toner according to the present invention), which contains an ester component in a proportion of 20% by weight or more and has a penetration of 4 or less. By associating wax particles composed of a certain wax in an aqueous medium, the equivalent circle diameter becomes 200
A step of forming secondary particles of about 500 nm and thermally fusing the secondary particles, the binder particles, and the colorant particles in an aqueous medium.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. <Toner> The toner of the present invention is a toner for developing an electrostatic image formed by thermally fusing wax particles, binder particles, and colorant particles, and the wax particles contain an ester component in an amount of 20% by weight or more. It is composed of a wax having a penetration of 4 or less and an equivalent circle diameter of 200 to 500 n.
It is characterized in that it comprises m substantially spherical wax domains.

<Wax Particles> The wax particles to be thermally fused with the binder particles and the colorant particles are composed of a wax containing an ester component in an amount of 20% by weight or more and having a penetration of 4 or less. Is done. Here, as the ester component, fatty acid ester, ethylene glycol ester of montanic acid, partially saponified product of ethylene glycol ester of montanic acid, glycerin-tri-1,2-hydroxystearate, and unsaturated alcohol and unsaturated acid are used. Esters and the like can be exemplified.

It is an essential condition that the wax constituting the wax particles contains the ester component in a proportion of 20% by weight or more in order to keep the melting point of the wax in the range of 60 to 110 ° C. If it is less than weight%,
The melting point of the wax exceeds 110 ° C., and the fixability deteriorates.

When the penetration of the wax is 4 or less, the mechanical strength of the toner can be increased.

Further, the melting point of the wax constituting the wax particles is preferably in the range of 60 to 110 ° C. If the melting point is too low, the fluidity is reduced due to the aggregation of the toner particles, and as a result, the transport amount is reduced and the image is deteriorated. In addition, at the time of fixing, sufficient release properties cannot be exhibited on the high temperature side, which causes offset.

Specific examples (commercially available) of such a wax include those shown in Table 1 below.

[0019]

[Table 1]

The wax particles are used in a state of being dispersed in an aqueous medium (aqueous dispersion). The aqueous dispersion of the wax particles is prepared by adding a wax to an aqueous medium in which a surfactant is dissolved (aqueous surfactant solution), performing emulsification and stirring under heating, and removing an alkali corresponding to at least the acid value of the wax. It can be prepared by adding and stabilizing. Here, the heating temperature at the time of emulsification and stirring is not less than the solid-liquid transition temperature of the wax or not less than the melting point of the wax.

The alkali may be added before the emulsification and stirring treatment is performed. Further, from the viewpoint of preventing the oxidation of the wax, it is preferable to use an aqueous solution of the surfactant which has been degassed and to carry out the emulsification and stirring treatment under a nitrogen stream or a nitrogen atmosphere. Further, from the viewpoint of obtaining a stable emulsified dispersion (aqueous dispersion), it is preferable to use a dedicated emulsification disperser.

Examples of the surfactant used for preparing the aqueous dispersion of the wax particles include nonionic surfactants. The amount of the surfactant is based on 100 parts by weight of the wax added. The amount is usually 1 to 20 parts by weight, and preferably 3 to 18 parts by weight.

The pH of the aqueous dispersion of wax particles is generally adjusted to 8.5 to 13, preferably 9.0 to 12.5, from the viewpoint of obtaining a stable emulsified dispersion. The concentration of the wax particles in the aqueous dispersion can be appropriately adjusted depending on the purpose, and is usually 10 to 30% by weight, preferably 15 to 28% by weight.

The average particle size of the wax particles in the aqueous dispersion can be appropriately adjusted depending on the emulsification conditions, and is usually from 20 to 300 nm. From the viewpoint of improving the emulsion stability of the wax particles, the average particle size is from 50 to 200 nm. It is preferably set to 50 to 150 nm, more preferably to 80 to 150 nm.

<Binder Particles> The binder particles to be subjected to heat fusion with the wax particles and the colorant particles may be selected from emulsion polymerization, suspension polymerization, dispersion polymerization, precipitation polymerization, and interfacial polymerization. Examples thereof include polymer particles prepared by a synthetic method and particles obtained by pulverizing a synthetic resin (polymer). Among these, polymer particles prepared by an emulsion polymerization method are preferred.

The glass transition temperature (Tg) of the binder resin constituting the binder particles is preferably in the range of -10 to 120 ° C, more preferably 0 to 90 ° C. The softening point (Ts) of the binder resin is 8
It is preferably in the range of 0 to 220 ° C.

As the monomer composition used for preparing the binder particles, the glass transition temperature (Tg) and the softening point (Ts) are within the above-mentioned preferred ranges, and the constitutional unit having a dissociable group is contained in 0.1%. It is not particularly limited as long as it can constitute a polymer containing 1 to 20% by weight.

The molecular weight of the binder resin constituting the binder particles is such that the weight average molecular weight (Mw) is 2,000.
It is preferably from 0 to 1,000,000, and more preferably from 8,000 to 500,000. Also,
As the molecular weight distribution of the binder resin, the ratio (Mw) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is used.
/ Mn) is preferably from 1.5 to 100, and more preferably from 1.8 to 50.

As the polymerizable monomer used for preparing the binder particles, one or two or more kinds of monomers essentially including a hydrophobic monomer can be used. Further, a crosslinkable monomer can be used in combination as needed. Further, it is preferable to use at least one monomer selected from monomers having an acidic polar group and monomers having a basic polar group, which will be described later.

(1) Hydrophobic monomer: The "hydrophobic monomer" which is an essential monomer component is not particularly limited, and may be a conventionally known monomer. .
Specifically, vinyl aromatic monomers, (meth) acrylate monomers, vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers And halogenated olefin monomers, and these can be used alone or in combination of two or more.

Examples of the vinyl aromatic monomer include styrene, o-methylstyrene, m-methylstyrene and p-methylstyrene.
-Methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octyl Styrene monomers such as styrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4-dimethylstyrene, and 3,4-dichlorostyrene, and derivatives thereof.

The (meth) acrylate monomers include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, and ethyl methacrylate. Butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and the like.

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, vinyl benzoate and the like. Examples of the vinyl ether monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether and the like. Examples of the monoolefin-based monomer include ethylene, propylene, isobutylene, 1-butene, 1-pentene, 4-methyl-1-pentene, and the like. Examples of the diolefin-based monomer include butadiene, isoprene, and chloroprene.

(2) Crosslinkable monomer Specific examples of the “crosslinkable monomer” used in combination to improve the properties of the binder particles include divinylbenzene, divinylnaphthalene, divinylether, diethylene glycol methacrylate, and ethylene glycol. Examples thereof include those having two or more unsaturated bonds, such as dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate.

(3) Monomer having acidic polar group "Monomer having acidic polar group" includes (i) an α, β-ethylenically unsaturated compound having a carboxyl group (—COOH), and ( ii) sulfonic acid group (-SO ₃ H)
Α, β-ethylenically unsaturated compounds having the formula:

(I) Specific examples of the α, β-ethylenically unsaturated compound having a carboxyl group include acrylic acid,
Methacrylic acid, fumaric acid, maleic acid, itaconic acid,
Examples thereof include cinnamic acid, monobutyl maleate, monooctyl maleate, and metal salts thereof (for example, Na salt and Zn salt).

(Ii) Specific examples of the α, β-ethylenically unsaturated compound having a sulfonic acid group include sulfonated styrene, Na salt of sulfonated styrene, allyl sulfosuccinic acid, octyl allyl sulfosuccinate, and octyl allyl sulfosuccinate. Na salt and the like.

(4) Monomer having a basic polar group The “monomer having a basic polar group” includes (i) an aliphatic alcohol having a substituted or unsubstituted amino group or a quaternary ammonium group. (Ii) (meth) acrylic acid ester, (ii) (meth) acrylic acid amide, or (meth) acrylic acid amide mono- or di-substituted on a nitrogen atom (N) with an alkyl group having 1 to 18 carbon atoms. ) Vinyl compounds substituted with a heterocyclic group having a nitrogen atom (N) as a ring member, and (iv) quaternary ammonium salts of N, N-diallyl-alkylamine and N, N-diallyl-alkylamine. Of these, the compound of the above (i) is preferable. The “aliphatic alcohol having a substituted or unsubstituted amino group or quaternary ammonium group” for obtaining the compound (i) preferably has 1 to 12 carbon atoms, more preferably 2 carbon atoms.
To 8, particularly preferably 2.

(I) Specific examples of (meth) acrylates of aliphatic alcohols having a substituted or unsubstituted amino group or a quaternary ammonium group include dimethylaminoethyl acrylate and quaternary ammonium salts of dimethylaminoethyl acrylate. Dimethylaminoethyl methacrylate, dimethylaminoethyl methacrylate 4
Quaternary ammonium salt diethylaminoethyl acrylate,
Quaternary ammonium salts of diethylaminoethyl acrylate diethylaminoethyl methacrylate, quaternary ammonium salts of diethylaminoethyl methacrylate, 3-dimethylaminophenyl acrylate, 2-hydroxy-
Examples thereof include 3-methacryloxypropyltrimethylammonium salt.

(Ii) Specific examples of (meth) acrylamide or (meth) acrylamide mono- or di-substituted with an alkyl group having 1 to 18 carbon atoms on a nitrogen atom (N) include acrylamide , N-butylacrylamide, N, N-dibutylacrylamide, piperidylacrylamide, methacrylamide, N-butylmethacrylamide, N, N-dimethylacrylamide, N-octadecylacrylamide and the like.

(Iii) Specific examples of the vinyl compound substituted with a heterocyclic group having a nitrogen atom (N) as a ring member include vinylpyridine, vinylpyrrolidone, vinyl-N-
Methylpyridinium chloride, vinyl-N-ethylpyridinium chloride and the like can be mentioned.

(Iv) Specific examples of N, N-diallyl-alkylamine include N, N-diallylmethylammonium chloride and N, N-diallylethylammonium chloride.

The obtained polymer (binder particles)
For the purpose of adjusting the molecular weight of the compound, a chain transfer agent can be used, and examples of such a chain transfer agent include mercaptans such as octyl mercaptan, dodecyl mercaptan, and tert-dodecyl mercaptan.

Examples of the polymerization initiator suitably used for obtaining the binder particles include a water-soluble radical polymerization initiator, and include persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds ( Peroxide compounds such as 4,4'-azobis-4-cyanovaleric acid and salts thereof, 2,2'-azobis (2-amidinopropane) salts, etc., hydrogen peroxide, benzoyl peroxide and the like. . Further, the above radical polymerization initiator can be used as a redox initiator in combination with a reducing agent. By using the redox initiator, the polymerization activity is increased, and the polymerization temperature can be lowered and the polymerization time can be shortened.

The polymerization temperature for obtaining the binder particles is as follows:
The temperature is not particularly limited as long as it is equal to or higher than the minimum radical generation temperature of the polymerization initiator, but is usually in the range of 50 to 80 ° C. Further, by using a polymerization initiator started at room temperature, for example, a combination of hydrogen peroxide and a reducing agent (such as ascorbic acid), it is possible to carry out polymerization at room temperature or a temperature close thereto.

Surfactants which can be used in the polymerization include sulfonates (sodium dodecylbenzenesulfonate, sodium arylalkyl polyethersulfonate, 3,3-disulfondiphenylurea-4,
Sodium 4-diazo-bis-amino-8-naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-
Triphenylmethane-4,4-diazo-bis-β-naphthol-6-sulfonate, etc.), sulfates (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.), fatty acid salts (olein, etc.) Sodium, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.).

<Colorant Particles> Examples of the colorant particles to be subjected to heat fusion with the binder particles and the wax particles include particles composed of an inorganic pigment and an organic pigment.

The inorganic pigments constituting the colorant particles include:
All conventionally known ones can be used. here,
Examples of black inorganic pigments include furnace black, channel black, acetylene black, thermal black, carbon black such as lamp black, magnetite, and magnetic powder such as ferrite.
These can be used alone or in combination of two or more. The use ratio of the colorant particles composed of an inorganic pigment is usually 2 to 100 parts by weight of the binder.
20 parts by weight.

The organic pigments constituting the colorant particles include:
All conventionally known ones can be used. here,
Pigments for magenta or red include C.I. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I.
I. Pigment Red 5, C.I. I. Pigment Red 6, C.I. I. Pigment Red 7, C.I. I. Pigment Red 15, C.I. I. Pigment Red 16, C.I. I.
Pigment Red 48: 1, C.I. I. Pigment Red 53: 1, C.I. I. Pigment Red 57: 1, C.I.
I. Pigment Red 122, C.I. I. Pigment Red 123, C.I. I. Pigment Red 139, C.I. I.
Pigment red 144, C.I. I. Pigment Red 1
49, C.I. I. Pigment Red 166, C.I. I. Pigment Red 177, C.I. I. Pigment Red 17
8, C.I. I. Pigment Red 222 and the like. Examples of orange or yellow pigments include C.I. I. Pigment Orange 31, C.I. I. Pigment Orange 43, C.I. I. Pigment Yellow 12,
C. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I.
I. Pigment Yellow 17, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 94, C.I. I.
Pigment Yellow 138 and the like.
Green or cyan pigments include C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15:
2, C.I. I. Pigment Blue 15: 3, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 60,
C. I. Pigment Green 7 and the like. These organic pigments can be used alone or in combination of two or more. The usage ratio of the colorant particles composed of the organic pigment is usually 2 to 20 parts by weight based on 100 parts by weight of the binder.

The colorant particles are preferably surface-treated with a surface modifier comprising a silane compound, a titanium compound, an aluminum compound and the like. As the surface modifier, all conventionally known surface modifiers can be used.

Here, the silane compound used as the surface modifier includes alkoxysilanes such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, diphenyldimethoxysilane and the like; silizane such as hexamethyldisilozane; γ-chloropropyltrimethoxysilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ
-Mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane and the like. Examples of the titanium compound include, for example, “Preneact” from Ajinomoto Co., Inc.
TTS, 9S, 38S, 41 marketed under the trade name
B, 46B, 55, 138S, 238S, etc., commercial products A-1, B-1, TOT, TST, T manufactured by Nippon Soda Co., Ltd.
AA, TAT, TLA, TOG, TBSTA, A-1
0, TBT, B-2, B-4, B-7, B-10, TB
STA-400, TTS, TOA-30, TSDMA,
TTAB, TTOP and the like. As the aluminum compound, for example, "Plenact AL-M" manufactured by Ajinomoto Co., Inc. and the like can be mentioned. The use ratio of the surface modifier is 0.01 to 100 parts by weight of the colorant particles.
To 20 parts by weight, more preferably 1 to 20 parts by weight.
To 15 parts by weight.

<Wax Domain> The toner of the present invention contains a substantially spherical wax domain having an equivalent circle diameter of 200 to 500 nm. Here, the “equivalent circle diameter of the wax domain” refers to the diameter of the circle when the circumference of the wax domain is considered as the circumference.

Further, since the wax domain having such a circle-equivalent diameter is contained in the toner, the toner can exhibit sufficient releasability (offset prevention effect) in a wide temperature range. . When the equivalent circle diameter of the wax domain is less than 200 nm, the toner containing the wax domain cannot exhibit the effect of preventing offset in a wide temperature range. On the other hand, if the circle-equivalent diameter exceeds 500 nm, the mechanical strength of the toner decreases, and sufficient durability cannot be maintained.

The content ratio of wax (wax domain) in the toner of the present invention is preferably 1 to 20% by weight. If the wax content is less than 1% by weight, sufficient releasability cannot be exhibited. On the other hand, when the content of the wax exceeds 20% by weight, the glass transition temperature of the toner decreases, and the toner particles aggregate, so that sufficient fluidity cannot be maintained.

The fact that wax is introduced into the toner of the present invention can be easily confirmed by directly observing the toner section with a transmission electron microscope or observing the peak of the melting point with a differential scanning calorimeter (DSC). can do. The confirmation of the shape of the wax domain in the toner particles and the measurement of the equivalent circle diameter can be performed as follows.

[Confirmation of Shape and Measurement of Equivalent Circle Diameter] Toner particles are embedded in a photocurable resin, cut into thin sections with a microtome “Urotracut E” (manufactured by Reichert-Jung), and the transmission electron microscope “LEM- 2000 "(manufactured by Topcon Co., Ltd.) and confirm the shape of the wax from the photograph. Equivalent to a wax domain circle using an image processing apparatus" SUPICCA "(manufactured by Nippon Avionics Co., Ltd.). Measure the diameter.

The toner of the present invention may contain various internal additives such as a charge control agent and external additives (post-additives). Here, as the charge control agent, a conventionally known positive charge control agent (eg, a nigrosine-based electron donating dye, a metal salt of naphthenic acid, a metal salt of a higher fatty acid, an alkoxylated amine,
Quaternary ammonium salts, alkyl amides, metal complexes, pigments, fluorinated activators, etc.) and negative charge control agents (electron accepting organic complexes, chlorinated paraffins, chlorinated polyesters, sulfonylamines of copper phthalocyanine, etc.) Can be used. When a monomer having a polar group is copolymerized to prepare a binder particle having a polar group on the surface, it may not be necessary to include the charge control agent. Here, the “polar group” refers to a group having a charge, whether positive or negative, such as a carboxyl group, a sulfonic acid group, an amino group, and an ammonium base.

Examples of the external additive include fine particles such as a fluidizing agent, a charge controlling agent and a lubricant. here,
As a fluidizing agent, inorganic fine powder, for example, hydrophobic silica,
Examples include titanium oxide, alumina, and sulfides, nitrides, and silicon carbides thereof. As the charge control agent,
Examples include polyvinylidene fluoride, polystyrene powder, polymethyl methacrylate powder, and polyethylene fine particles. As a lubricant, cadmium salt of stearic acid,
Barium salt, nickel salt, cobalt salt, strontium salt, copper salt, magnesium salt, calcium salt, etc .; zinc oleate, manganese salt, iron salt, cobalt salt, copper salt, lead salt, magnesium salt; zinc palmitate Salts, cobalt salts, copper salts, magnesium salts, silicon salts, calcium salts;
Linoleic acid zinc salt, cobalt salt, calcium salt; ricinoleic acid zinc salt, cadmium salt; caprylic acid lead salt,
Metal salts of higher fatty acids such as lead salts of caproic acid can be mentioned.

The average particle size (volume average particle size) of the toner of the present invention is usually 3 to 20 μm, preferably 4 to 20 μm.
１５15 μm. Here, the average particle size of the toner is
It can be measured using "Coulter Multisizer II" (manufactured by Coulter Inc.). The toner of the present invention may be used as a one-component developer without being mixed with a carrier, but is preferably used as a two-component developer by being mixed with a carrier. The toner of the present invention constituting the one-component developer may be either a non-magnetic toner containing no magnetic particles or a magnetic toner containing magnetic particles. Here, the particle size of the magnetic particles is about 0.1 to 5 μm.

As the carrier constituting the two-component developer, conventionally known carriers can be used, for example, metals such as iron, ferrite and magnetite, and alloys of these metals with metals such as aluminum and lead. Conventionally known magnetic particles can be used. Especially Li ₂ O, Mg
Magnetic particles composed of Fe ₂ O ₃ containing at least one of O and MnO are preferred. The volume average particle diameter of the magnetic particles is 15 to 100 μm, more preferably 20 to 60 μm.
μm is preferred.

The volume average particle size of the carrier can be measured by a laser diffraction type particle size distribution analyzer “HELOS (HEL)
OS) (manufactured by SYMPATEC).

The carrier is such that the surface of the magnetic particles is coated with a known resin such as an olefin resin, a styrene resin, a styrene-acrylic resin, a silicone resin, an ester resin, and a fluorine-containing polymer resin. Is preferred.

The specific resistance of the carrier is 10 ⁵ to 10 ¹⁴ Ω · c
m is preferable. If the specific resistance is too low, charge injection may occur. On the other hand, if the specific resistance is too high, the electric charge does not easily reach the upper surface of the developing layer (the tip of the developer spike), and the developability decreases.

The carrier has a magnetization of 20 to 60 emu / cm.
³ , more preferably 30 to 50 e
mu / cm ³ . If the magnetization is too small, the carrier tends to adhere to the non-developing portion of the photoreceptor.On the other hand, if the magnetization is too large, a soft and uniform developing layer is formed on the developing sleeve. Becomes difficult.

<Method of Manufacturing Toner (Method of Introducing Wax)
The following methods (1) to (5) can be mentioned as a method for producing the toner of the present invention by introducing wax particles dispersed in an aqueous medium into toner particles.

(1) An aqueous dispersion of wax particles, an aqueous dispersion of colorant particles, and an aqueous dispersion of binder particles are mixed at a predetermined ratio, and the wax particles, the binder particles, and the colorant are mixed. The particles are aggregated according to a conventional method, and heat-fused at a temperature of Tg to Tg + 50 ° C. (Tg: glass transition temperature of the binder particles), cooled to room temperature, and repeatedly washed and filtered for purification. A method of drying at a temperature of Tg or less.

(2) An aqueous dispersion of wax particles, a monomer mixture for obtaining binder particles, and a surfactant are added to an aqueous phase, and the system is heated to a polymerization temperature with stirring. Then, an aqueous dispersion of wax particles and binder particles is prepared by adding a radical polymerization initiator and copolymerizing the monomer mixture. Next, an aqueous dispersion of colorant particles is added to the obtained aqueous dispersion and mixed, and the wax particles, the binder particles, and the colorant particles are aggregated according to a conventional method, and Tg to Tg + 50 ° C. And then cooling to room temperature, repeating purification and washing and filtration, and then drying at a temperature of Tg or less.

(3) An aqueous dispersion of wax particles, an aqueous dispersion of colorant particles, a monomer mixture for obtaining binder particles, and a surfactant are added to an aqueous phase. After raising the temperature to the polymerization temperature with stirring, an aqueous dispersion of wax particles, colorant particles and binder particles is prepared by adding a radical polymerization initiator and copolymerizing the monomer mixture. Next, in the obtained aqueous dispersion, the wax particles, the colorant particles, and the binder particles are agglomerated according to a conventional method.
g to Tg + 50 ° C., then cooled to room temperature, and repeatedly washed and filtered for purification.
A method of drying at the following temperature.

(4) By associating wax particles in an aqueous medium according to a conventional method, the equivalent circle diameter is 200 to 5
Form secondary particles of 00 nm. Next, in the aqueous dispersion of the secondary particles, an aqueous dispersion of binder particles and an aqueous dispersion of colorant particles are added and mixed, and the secondary particles, the binder particles, and the colorant particles are mixed. Are aggregated according to a conventional method, thermally fused at a temperature of Tg to Tg + 50 ° C., cooled to room temperature, washed and filtered repeatedly, purified, and then dried at a temperature of Tg or lower.

(5) Secondary particles having an equivalent circle diameter of 200 to 500 nm are formed by associating the wax particles in an aqueous medium in which the wax particles and the colorant particles are dispersed. Next, in the aqueous dispersion of the secondary particles and the colorant particles, an aqueous dispersion of the binder particles is added and mixed, and the secondary particles, the binder particles, and the colorant particles are aggregated according to a conventional method. Tg to T
g + 50 ° C., and then cooled to room temperature.
A method in which purification is performed by repeating washing and filtration, followed by drying at a temperature of Tg or less.

By the methods (1) to (5), wax particles (wax domains) can be introduced into the toner particles. According to the above methods (4) and (5), even if the particle size of the wax particles is 80 to 150 nm (the particle size at which good emulsification stability is obtained), the circle equivalent diameter is contained in the toner particles. Of 200 to 500 nm can be reliably introduced.

[0072]

Hereinafter, embodiments of the present invention will be described.
The present invention is not limited to these.

<Preparation Example of Aqueous Dispersion of Wax Particles> [Preparation Example (W-1)] A 1000 ml four-headed kolben equipped with a stirrer, a temperature sensor, a nitrogen inlet tube and a cooling tube was formulated as shown in Table 2. Degassed distilled water 500 according to
ml and nonionic surfactant "Newcol 565C"
28.5 g (manufactured by Nippon Emulsifier Co., Ltd.) and 185.5 g of "Carnauba Wax No. 1" (manufactured by Noda Wax Co., Ltd.) were charged and heated while stirring under a nitrogen stream. When the temperature of the contents reached 85 ° C, a 5N aqueous sodium hydroxide solution was added, and the temperature was raised to 95 ° C.
Stirring was continued for hours. Next, the content was cooled to room temperature to obtain an emulsified dispersion having a pH of 11.2 and a solid concentration of 26% by weight (aqueous dispersion of wax particles.
It is called "wax dispersion (W-1)". ) Got. The particle size of the wax particles dispersed in the wax dispersion (W-1) was measured by a dynamic light scattering particle size analyzer “ELS-80”.
As a result of measurement using "0" (manufactured by Otsuka Electronics Co., Ltd.), the average particle size was 120 nm.

[Preparation Example (W-2)] 1000 ml of 4 ml equipped with a stirrer, a temperature sensor, a nitrogen inlet tube and a cooling tube.
According to the recipe shown in Table 2, 500 ml of degassed distilled water, 12.5 g of nonionic surfactant "Newcol 565C" (manufactured by Nippon Emulsifier Co., Ltd.), and "Carnauba wax No. 1" (Noda) 185.
5 g, and the mixture was heated while stirring under a nitrogen stream. When the temperature of the content reached 85 ° C, a 5N aqueous sodium hydroxide solution was added, the temperature was raised to 95 ° C, and stirring was continued at that temperature for 1 hour. Next, the content is cooled to room temperature to obtain an emulsified dispersion having a pH of 11.2 and a solid concentration of 26% by weight (aqueous dispersion of wax particles; hereinafter, referred to as "wax dispersion (W-2)"). .). The particle size of the wax particles dispersed in the wax dispersion (W-2) was determined by a dynamic light scattering particle size analyzer "E
When measured using "LS-800" (manufactured by Otsuka Electronics Co., Ltd.), the average particle size was 280 nm.

[Preparation Example (W-3)] 1000 ml of 4 equipped with a stirrer, a temperature sensor, a nitrogen inlet tube and a cooling tube.
According to the prescription shown in Table 2, 500 ml of degassed distilled water, 12.5 g of nonionic surfactant "Newcol 565C" (manufactured by Nippon Emulsifier Co., Ltd.) and "Canderia Wax (*)" (Noda) 185.
5 g, and the mixture was heated while stirring under a nitrogen stream. When the temperature of the content reached 50 ° C., a 5N aqueous sodium hydroxide solution was added, the temperature was raised to 75 ° C., and stirring was continued at that temperature for 1 hour. Next, the content is cooled to room temperature to obtain an emulsified dispersion having a pH of 10.8 and a solid content concentration of 26% by weight (aqueous dispersion of wax particles; hereinafter, referred to as "wax dispersion (W-3)"). .). The particle size of the wax particles dispersed in the wax dispersion (W-3) was determined by a dynamic light scattering particle size analyzer "E.
As a result of measurement using "LS-800" (manufactured by Otsuka Electronics Co., Ltd.), the average particle size was 105 nm.

[Preparation Example (W-4)] 1000 ml of 4 ml equipped with a stirrer, a temperature sensor, a nitrogen inlet tube and a cooling tube.
According to the recipe shown in Table 2, 500 ml of degassed distilled water, 12.5 g of nonionic surfactant "Newcol 565C" (manufactured by Nippon Emulsifier Co.), and "Candelilla wax No. 1" (Noda) (Wax) 18
5.5 g, and the temperature was increased while stirring under a nitrogen stream. When the temperature of the content reached 50 ° C., a 5N aqueous sodium hydroxide solution was added, the temperature was raised to 75 ° C., and stirring was continued at that temperature for 1 hour. Then, the content is cooled to room temperature to obtain an emulsified dispersion having a pH of 10.7 and a solid content of 26% by weight (aqueous dispersion of wax particles; hereinafter, referred to as "wax dispersion (W-4)"). .). The particle size of the wax particles dispersed in the wax dispersion (W-4) was measured using a dynamic light scattering particle size analyzer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.). The diameter was 112 nm.

[0077]

[Table 2]

<Example of Preparation of Aqueous Dispersion of Colorant Particles> As colorant particles, 100 g of carbon black “Mogal L” (manufactured by Cabot) and 25 g of sodium dodecyl sulfate
Was added to 540 ml of distilled water, and the mixture was sufficiently stirred, and then subjected to a dispersion treatment using a pressure type disperser “MINI-LAB” (manufactured by Learny) to obtain an aqueous dispersion of carbon black (hereinafter referred to as “colorant dispersion”). Liquid (C) "). The particle size of the carbon black dispersed in the colorant dispersion liquid (C) was measured using a dynamic light scattering particle size analyzer “ELS”.
The average particle size was 82 nm when measured using "-800" (manufactured by Otsuka Electronics Co., Ltd.).

<Preparation Example of Aqueous Dispersion of Binder Particles> [Preparation Example (HP-1)] A 1000 ml four-headed kolben equipped with a stirrer, a temperature sensor, a nitrogen inlet tube and a cooling tube was charged with the formulation shown in Table 3. 480 ml of distilled water, 0.6 g of sodium dodecyl sulfate, and 106.4 of styrene.
g, 43.2 g of n-butyl acrylate, and 10.4 g of methacrylic acid, and the temperature was increased while stirring under a nitrogen stream. When the temperature of the contents reached 70 ° C., 2.1 g of potassium persulfate (polymerization initiator) was added to 120 m
The polymerization was completed by adding an aqueous initiator solution dissolved in 1 l of distilled water and continuing stirring at 70 ° C. for 3 hours under a nitrogen stream. Next, by cooling the content to room temperature, an aqueous dispersion having a solid content concentration of 21% by weight (aqueous dispersion of binder particles or less, "binder dispersion (HP
-1) ". ) Got. This binder dispersion (H
When the particle size of the binder particles dispersed in P-1) was measured using a dynamic light scattering particle size analyzer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), the average particle size was 105.
nm.

[Preparation Example (LP-1)] Into a 5000 ml four-headed kolben equipped with a stirrer, a temperature sensor, a nitrogen inlet tube and a cooling tube, distilled water 24 was prepared according to the recipe shown in Table 3.
00 ml, sodium dodecyl sulfate 2.8 g, styrene 620 g, n-butyl acrylate 128 g,
52 g of methacrylic acid and 27.4 g of tert-dodecyl mercaptan were charged and heated while stirring under a nitrogen stream. When the temperature of the contents reaches 70 ° C,
600 ml of potassium persulfate (polymerization initiator) 11.2 g
The polymerization was completed by adding an aqueous solution of an initiator dissolved in distilled water at 70 ° C. for 3 hours under a nitrogen stream. Next, by cooling the content to room temperature, an aqueous dispersion having a solid content concentration of 21% by weight (aqueous dispersion of binder particles or less, "binder dispersion (LP-
1) ". ) Got. This binder dispersion (LP
The particle size of the binder particles dispersed in -1) was measured using a dynamic light scattering particle size analyzer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.), and the average particle size was 115 n.
m.

[Preparation Example (HP-2)] Into a 1000 ml four-headed kolven equipped with a stirrer, a temperature sensor, a nitrogen inlet tube and a cooling tube, distilled water 46 was prepared according to the recipe shown in Table 3.
3 ml, 0.6 g of sodium dodecyl sulfate, and the wax dispersion (W-2) obtained in Preparation Example (W-2).
0 g, 106.4 g of styrene, 43.2 g of n-butyl acrylate, and 10.4 g of methacrylic acid were charged, and heated while stirring under a nitrogen stream. When the temperature of the contents reached 70 ° C., an initiator aqueous solution obtained by dissolving 2.1 g of potassium persulfate (polymerization initiator) in 120 ml of distilled water was added, and the mixture was heated at 70 ° C. for 3 hours under a nitrogen stream. The polymerization was completed by continuing the stirring. Then, the content was cooled to room temperature, so that the solid content concentration was 21%.
By weight, an aqueous dispersion (an aqueous dispersion of binder particles, hereinafter referred to as "binder dispersion (HP-2)") was obtained. The particle size of the binder particles dispersed in the binder dispersion liquid (HP-2) was measured using a dynamic light scattering particle size analyzer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.). The diameter was 115 nm.

[Preparation Example (LP-2)] Distilled water (23 ml) was added to a 5000 ml four-headed kolven equipped with a stirrer, a temperature sensor, a nitrogen inlet tube and a cooling tube according to the recipe shown in Table 3.
09 ml, 2.8 g of sodium dodecyl sulfate, and the wax dispersion (W-2) 12 obtained in Preparation Example (W-2).
3.0 g, 620 g of styrene, 128 g of n-butyl acrylate, 52 g of methacrylic acid, and 27.4 g of tert-dodecyl mercaptan were charged, and heated while stirring under a nitrogen stream. The temperature of the contents is 70 ° C
At which point potassium persulfate (polymerization initiator)
An initiator aqueous solution obtained by dissolving 2 g in 600 ml of distilled water was added thereto, and the polymerization was completed by continuing stirring at 70 ° C. for 3 hours under a nitrogen stream. Next, the content was cooled to room temperature to obtain an aqueous dispersion having a solid content of 21% by weight (hereinafter, referred to as an aqueous dispersion of binder particles, hereinafter referred to as "binder dispersion (LP-2)"). The particle size of the binder particles dispersed in the binder dispersion liquid (LP-2) was measured by a dynamic light scattering particle size analyzer “ELS-80”.
The average particle size was measured using "0" (manufactured by Otsuka Electronics Co., Ltd.).

[0083]

[Table 3]

Example 1 In a 1000 ml separable flask equipped with a stirrer, a condenser and a temperature sensor, 47.6 g of a binder dispersion (HP-2) and 190.5 g of a binder dispersion (LP-2) were placed. 7.7 g of wax dispersion (W-3) and colorant dispersion (C)
After mixing and stirring 7 g and 252.5 ml of distilled water, 5N aqueous sodium hydroxide solution was added to adjust the pH of the system to 9.5. While further stirring, an aqueous sodium chloride solution obtained by dissolving 50 g of sodium chloride in 600 ml of distilled water, and isopropanol 77
ml and the fluorine-based nonionic surfactant "Fluorard F
C-170C "(manufactured by Sumitomo 3M), 10 mg of a surfactant aqueous solution obtained by dissolving in 10 ml of distilled water.
By raising the temperature of the content to 85 ° C. and continuing stirring for 6 hours, the wax particles, the binder particles, and the colorant particles were thermally fused. Next, the content was cooled to room temperature, and the pH of the content was adjusted to 13 by adding a 5N aqueous sodium hydroxide solution. Next, the solid content filtration process and the resuspension process in distilled water are repeated,
Thereafter, by washing and drying, the toner (T-1) of the present invention was obtained.

The volume average particle diameter (d) of this toner (T-1)
₅₀₎ was measured using the "Coulter Multisizer II" (manufactured by Beckman Coulter, Inc.), d ₅₀ = 6.55μm, CV
= 20%. Also, the presence of the wax in the toner (T-1) was determined by a differential scanning calorimeter “DSC-50”.
(Manufactured by Shimadzu Corporation). Further, the toner particles constituting the toner (T-1) are embedded in a photocurable resin, and the microtome "Urotracut E" (R
Eicert-Jung Co., Ltd.), sliced, photographed using a transmission electron microscope “LEM-2000” (manufactured by Topcon Co., Ltd.), confirmed the wax shape from the photograph, and further performed an image processing device “ When the circle equivalent diameter of the wax domain was measured using “SUPICCA” (manufactured by Nippon Avionics Co., Ltd.), the shape of the wax domain was spherical, and the circle equivalent diameter was 290 nm.

Example 2 A 1000 ml separable flask equipped with a stirrer, a cooling tube and a temperature sensor was charged with 7.7 g of a wax dispersion (W-1) and 25 ml of distilled water.
After 2.5 ml and 26.7 g of the colorant dispersion (C) were charged and mixed and stirred, 50 g of sodium chloride was added to distilled water 6.
Sodium chloride aqueous solution dissolved in 00 ml, isopropanol 77 ml, fluorinated nonionic surfactant "Fluorard FC-170C" (Sumitomo 3M) 10
An aqueous solution of a surfactant prepared by dissolving mg in 10 ml of distilled water was sequentially added, and stirring was continued. After confirming that the wax particles in this system were associated and the particle size of the secondary particles became 350 nm, the binder dispersion (HP-1)
47.6 g, and a binder dispersion (LP-1) 190.
By adding a mixture of 5 g (a mixture adjusted to pH 9.5 with a 5N aqueous sodium hydroxide solution), raising the temperature of the contents to 85 ° C., and continuing stirring for 6 hours. The secondary particles, the binder particles, and the colorant particles were heat-sealed. Next, the content was cooled to room temperature, and the pH of the content was adjusted to 13 by adding a 5N aqueous sodium hydroxide solution. Next, the solid content filtration process and the resuspension process in distilled water are repeated,
Thereafter, by washing and drying, the toner (T-2) of the present invention was obtained. The volume average particle diameter (d ₅₀ ) of this toner (T-2) was measured using “Coulter Multisizer II” (manufactured by Coulter Corporation), and it was found that d ₅₀ = 6.48 μm.
m, CV = 19%. Further, the presence of the wax in the toner (T-2) was confirmed by a differential scanning calorimeter “DSC-
50 "(manufactured by Shimadzu Corporation). Further, the shape of the wax domain confirmed in the same manner as in Example 1 was spherical, and the equivalent circle diameter was 375 n.
m.

Example 3 Same as Example 2 except that 7.7 g of wax dispersion (W-3) was used instead of wax dispersion (W-1) according to the formulation shown in Table 4 below. Thus, the toner (T-3) of the present invention was obtained. The volume average particle diameter (d ₅₀ ) of this toner (T-3) was measured using “Coulter Multisizer II” (manufactured by Coulter Corporation), and it was found that d ₅₀ = 6.61 μm and CV = 18%.
The presence of the wax in the toner (T-3)
It could be confirmed using a differential scanning calorimeter “DSC-50” (manufactured by Shimadzu Corporation). Further, the shape of the wax domain confirmed in the same manner as in Example 1 was spherical,
The equivalent circle diameter was 360 nm.

Example 4 Same as Example 2 except that 7.7 g of wax dispersion (W-4) was used in place of wax dispersion (W-1) according to the formulation shown in Table 4 below. Thus, a toner (T-4) of the present invention was obtained. The volume average particle diameter (d ₅₀ ) of the toner (T-4) was measured using “Coulter Multisizer II” (manufactured by Coulter), and it was found that d ₅₀ = 6.42 μm and CV = 21%.
The presence of the wax in the toner (T-4)
It could be confirmed using a differential scanning calorimeter “DSC-50” (manufactured by Shimadzu Corporation). Further, the shape of the wax domain confirmed in the same manner as in Example 1 was spherical,
Its circle equivalent diameter was 410 nm.

Comparative Example 1 In a 1000 ml separable flask equipped with a stirrer, a cooling pipe and a temperature sensor, 47.6 g of the binder dispersion (HP-1) and 190.5 g of the binder dispersion (LP-1) were placed. 7.7 g of wax dispersion (W-1) and colorant dispersion (C)
After mixing and stirring 7 g and 252.5 ml of distilled water, 5N aqueous sodium hydroxide solution was added to adjust the pH of the system to 9.5. While further stirring, an aqueous sodium chloride solution obtained by dissolving 50 g of sodium chloride in 600 ml of distilled water, and isopropanol 77
ml and the fluorine-based nonionic surfactant "Fluorard F
C-170C "(manufactured by Sumitomo 3M), 10 mg of a surfactant aqueous solution obtained by dissolving in 10 ml of distilled water.
The temperature of the contents was increased to 85 ° C. and stirring was continued for 6 hours. Next, the content was cooled to room temperature, and the pH of the content was adjusted to 13 by adding a 5N aqueous sodium hydroxide solution. Next, the solid was filtered and resuspended in distilled water repeatedly, and then washed and dried to obtain a comparative toner (t-1). The volume average particle diameter (d ₅₀ ) of this toner (t-1) was measured using “Coulter Multisizer II” (manufactured by Coulter), and it was found that d ₅₀ = 6.59 μm and CV = 20%.
The presence of the wax in the toner (t-1)
It could be confirmed using a differential scanning calorimeter “DSC-50” (manufactured by Shimadzu Corporation). Further, the shape of the wax domain confirmed in the same manner as in Example 1 was spherical,
Its circle equivalent diameter was 105 nm.

<Comparative Example 2> Same as Comparative Example 1 except that 7.7 g of wax dispersion (W-3) was used instead of wax dispersion (W-1) according to the formulation shown in Table 4 below. Thus, a comparative toner (t-2) was obtained. The volume average particle diameter (d ₅₀ ) of this toner (t-2) was measured using “Coulter Multisizer II” (manufactured by Coulter Corporation). As a result, d ₅₀ = 6.55 μm and CV = 21%.
The presence of the wax in the toner (t-2)
It could be confirmed using a differential scanning calorimeter “DSC-50” (manufactured by Shimadzu Corporation). Further, the shape of the wax domain confirmed in the same manner as in Example 1 was spherical,
The equivalent circle diameter was 89 nm.

[0091]

[Table 4]

<Preparation of Developer> For each of the toners obtained in Examples 1 to 4 and Comparative Examples 1 and 2, hydrophobic silica fine particles (primary average particle diameter = 12 nm) were used as external additives.
Was added and mixed at a ratio of 2% by weight, and 7 parts by weight of the externally added toner and a carrier composed of ferrite particles whose surface was coated with a styrene-acrylic resin (volume average particle size =
(30 μm) and 93 parts by weight to prepare two-component developers (Developers 1-4 and Comparative Developers 1-2).

<Evaluation of Developer> Using each of Developers 1-4 and Comparative Developers 1-2 obtained as described above,
A color modified with a photoconductor (laminated organic photoconductor), a developing device for a two-component developer, and a heat roller fixing device as shown in FIG. 1 so that the set temperature of the heat roller can be variably adjusted. A test for forming a fixed toner image was performed using an electrophotographic copying machine “9028” (manufactured by Konica Corporation) while changing the set temperature of the heat roller stepwise within the range of 100 to 230 ° C. Was evaluated. The results are shown in Table 5 below. In FIG. 1 showing the heat roller fixing device,
1 is a heat roller, 2 is a heat source (linear heater), 3 is a pressure roller, 4 is an impregnating roller, P is a transfer paper, T is a toner image, and the heat roller 1 has a metal cylinder surface coated with resin. The pressure roller 3 is made of silicone rubber. The heat roller fixing device has a linear pressure of 7N.
/ Cm, a nip width of 3.5 mm, a linear velocity of 210 mm / sec, and without a cleaning mechanism.

(1) Minimum fixing temperature: A front end of the obtained fixed toner image in the image advancing direction is rubbed with a constant load by a rubbing tester, and then the end of the end is measured with a microdensitometer. Measure the residual ratio of the fixed toner image,
The minimum value of the set temperature of the heat roller when this residual ratio is 80% or more (fixed minimum set temperature) was determined.

(2) Offset occurrence temperature: A fixed toner image is formed using a document having a solid black portion with a width of 10 mm at the leading end of the image. Immediately after that, a blank transfer paper is heated with a heat roller under the same conditions. The operation of sending the toner to the fixing device and visually observing whether or not toner contamination occurs is performed at each set temperature of the heat roller (in increments of 10 °). Temperature).

(3) Image Smearing: A continuous copy of 50,000 times was carried out by using a color electrophotographic copying machine “9028” (manufactured by Konica Corporation) using a remodeled machine with a pixel rate of 5% under the following conditions. After a lapse of 24 hours, a blank document was copied and the state of stain on the copied image was observed.

[Conditions] Surface potential of photoconductor (laminated organic photoconductor): -550 V DC bias: -250 V AC bias: Vp-p: -50 to -450 V Alternating electric field frequency: 1800 Hz Minimum gap (Dsd): 300 μm ・ Pressing regulating force: 10 gf / mm ・ Pressing regulating rod: SUS416 (made of magnetic stainless steel)
/ Diameter 3mm ・ Developer layer thickness: 150μm ・ Developing sleeve: 20mm ・ Set temperature of heat roller: 180 ℃ ・ Environmental conditions: temperature 25 ℃, relative humidity 30%

[0098]

[Table 5]

[0099]

The toner of the present invention has good releasability, and is excellent in offset resistance and low-temperature fixability. According to the toner of the present invention, a high-quality visible image free from image stains can be formed stably for a long period of time. According to the production method of the present invention, it is possible to reliably produce a polymerized toner having good releasability, and excellent in offset resistance and low-temperature fixability. According to the production method of the present invention, a large diameter (equivalent circle diameter of 200 to 500
m) wax domains can be formed.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a heat roller fixing device of a copying machine used for evaluation of a developer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat roller 2 Heat source 3 Pressure roller 4 Impregnation roller P Transfer paper T Toner image

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Mikio Kamiyama 1 Sakuracho, Hino-shi, Tokyo Konica Corporation F-term (reference) 2H005 AA01 AA06 AB03 CA04 CA14 DA06 DA10 EA03 EA05 EA07 EA10 FB02

Claims (9)

[Claims] 1. A toner for developing an electrostatic image, which is obtained by thermally fusing wax particles, binder particles and colorant particles, wherein the wax particles contain an ester component in a proportion of 20% by weight or more, A toner comprising a wax having a penetration of 4 or less and a wax domain having an equivalent circle diameter of 200 to 500 nm. 2. The toner according to claim 1, wherein the melting point of the wax constituting the wax particles is in the range of 60 to 110 ° C. 3. The wax particles having an average particle size of 50 to 150.
The toner according to claim 1, wherein the toner is in a range of nm. 4. The toner according to claim 1, wherein the content of the wax is 1 to 20% by weight. 5. The toner according to claim 1, wherein the binder resin constituting the binder particles is a styrene- (meth) acrylate copolymer. 6. The method for producing a toner according to claim 1, wherein a wax containing an ester component in a proportion of 20% by weight or more and having a penetration of 4 or less is emulsified and dispersed. An aqueous dispersion of particles, an aqueous dispersion of binder particles, and an aqueous dispersion of colorant particles are mixed, and the wax particles, the binder particles, and the colorant particles are thermally fused in an aqueous medium. A method for producing a toner. 7. The method for producing a toner according to claim 6, wherein the melting point of the wax constituting the wax particles is in the range of 60 to 110 ° C. 8. The pH of the aqueous dispersion of wax particles is 8.
The method for producing a toner according to claim 6, wherein the toner is in a range of 5 to 13. 9. The method for producing a toner according to claim 1, wherein the wax particles containing an ester component in a proportion of 20% by weight or more and having a penetration of 4 or less are aqueous. By associating in the medium, the equivalent circle diameter becomes 200
A method for producing a toner, comprising a step of forming secondary particles of about 500 nm and thermally fusing the secondary particles, binder particles, and colorant particles in an aqueous medium.