JP2023012688A - Toner and method for manufacturing the same, toner storage unit, image forming apparatus, and image forming method - Google Patents

Abstract

To provide a toner that can prevent the occurrence of an abnormal image due to filming and achieve both low temperature fixability and excellent cleaning properties with its low adhesion strength at a high level.SOLUTION: A toner has a plurality of resin fine particles observed by a scanning electron microscope (SEM) on the surface of a toner base particle. The toner includes at least resin and wax. When the major axis of the minimum particle of the resin fine particles is R, and the resin fine particles satisfying the major axis 3R or more are an aggregate, the ratio of the aggregates occupying the surface of the toner base particle is 15% or more and 60% or less.SELECTED DRAWING: Figure 1

Description

The present invention relates to a toner and its manufacturing method, a toner storage unit, an image forming apparatus, and an image forming method.

Toner must have small particle size and high-temperature offset resistance to improve output image quality, low-temperature fixability to save energy, and heat-resistant storage that can withstand high temperatures and high humidity during storage and transportation after manufacturing. gender is required. In particular, since the power consumption during fixing accounts for most of the power consumption in the image forming process, it is very important to improve the low-temperature fixability.

In recent years, for the purpose of obtaining a toner capable of achieving both low-temperature fixability and heat-resistant storage stability, composite resin particles in which fine resin particles containing two kinds of resins as constituent components within the same particle adhere to the surface of the resin particles have been developed. A method for producing composite resin particles has been proposed that includes a removal step of removing part or all of the resin of the resin fine particles after formation (see, for example, Patent Documents 1 and 2).
In addition, for the purpose of obtaining a toner that has high heat-resistant storage stability and can suppress toner aggregation even after long-term use, the core layer contains a styrene-acrylic modified polyester resin and is covered with a styrene-acrylic resin component. A toner coated with spherical particles for a shell has been proposed (see, for example, Patent Document 3).

In addition, by using wet-process silica, which can control larger particle diameters than dry-process silica, it has a spacer effect and prevents toner from coming into contact with each other, thereby maintaining low-temperature fixability and preventing the occurrence of image defects. For the purpose of obtaining a toner capable of forming stable images for a long period of time, a toner containing a crystalline resin and silica particles treated with silicone oil and having an average primary particle size of 50 nm or more and 150 nm or less is proposed. (See Patent Document 4, for example).

Furthermore, in order to prevent silica from liberating due to friction between toner particles and from burying silica in the toner surface, a toner containing non-spherical silica as an external additive has been proposed (see, for example, Patent Document 5). reference). In the invention described in Patent Document 5, by increasing the contact area between the external additive and the toner base, the separation and burial of the external additive due to friction between toner particles or between the toner and the carrier is suppressed. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner capable of suppressing the occurrence of abnormal images due to filming and having both low-temperature fixability and excellent cleanability due to low adhesion at a high level.

The toner of the present invention as a means for solving the above-mentioned problems is a toner having a plurality of resin fine particles observed with a scanning electron microscope (SEM) on the surface of toner base particles, wherein the toner comprises a resin and wax, wherein R is the major diameter of the smallest particle in the resin fine particles, and when the resin fine particles satisfying the major diameter of 3R or more are aggregated, the ratio of the aggregates occupying the surface of the toner base particles is 15. % or more and 60% or less.

According to the present invention, it is possible to provide a toner capable of suppressing the occurrence of abnormal images due to filming and having both low-temperature fixability and excellent cleanability due to low adhesion at high levels.

FIG. 1 is a schematic diagram showing an example of the state of the toner surface. FIG. 2 is a schematic diagram showing an example of the process cartridge of the present invention. FIG. 3 is a schematic diagram showing an example of the image forming apparatus of the present invention.

(toner)
The present invention provides a toner having a plurality of resin fine particles observed by a scanning electron microscope (SEM) on the surface of a toner base particle, wherein the toner contains at least a resin and a wax, and the resin fine particles have a minimum When the long diameter of a particle is defined as R and the fine resin particles having a long diameter of 3R or more are aggregated, the ratio of the aggregate to the surface of the toner base particle is 15% or more and 60% or less, and further optionally and has another component (A).
In the present invention, particles in which the fine resin particles are present on the surface of the toner base particles are sometimes referred to as composite particles.

In general, in order to improve the low-temperature fixability of the toner, it is necessary to use a low-melting material for the toner. Therefore, there is a trade-off between low-temperature fixability, heat-resistant storage stability, and adhesion.

In the prior arts described in Patent Documents 1 to 3, there is a problem that, in the toner excellent in low-temperature fixability, poor cleaning caused by deterioration of adhesion is not sufficiently solved. Therefore, when even higher low-temperature fixability is required, a means for resolving the contradictory adhesion force is required.
In the prior art described in Patent Document 3 (Japanese Patent Application Laid-Open No. 2013-011644), there is a problem that the shell layer inhibits heat transfer from the fixing roller and sufficient low-temperature fixability cannot be obtained. .

In the prior art described in Patent Document 4 (Japanese Patent Application Laid-Open No. 2009-098194), a small particle size external additive (for example, silica) added to the surface of the toner particles is detached from the toner and adhered onto the photoreceptor. Afterwards, they agglomerate and densify to form strongly adhering silica, which causes the problem of the occurrence of abnormal images due to so-called filming.
In addition, since the particle size range of the external additive in the prior art described in Patent Document 4 includes silica having a large particle size of 120 nm to 150 nm, it is said that an abnormal image is likely to occur due to silica liberation. There's a problem. Further, with the conventional toner, silica is likely to be liberated due to friction between toner particles, and there is concern about the occurrence of abnormal images such as filming and image blurring.
In order to prevent detachment of the external additive, it is necessary to strongly adhere the external additive to the surface of the toner base particles with a strong force of the mixer. Therefore, there is a problem that the desired effect cannot be obtained.

Therefore, the fundamental cause of filming is the liberation of external additives (silica, etc.) adhered to the surface of toner base particles. Since there is a trade-off relationship between properties, adhesive strength, and heat-resistant storage stability, it is difficult to satisfy all qualities.

As a result of extensive studies, the present inventors have found that aggregates composed of fine resin particles are present on the surface of toner base particles, and that the proportion of the aggregates on the surface of toner base particles is 15% or more and 60% or less. As a result, an appropriate amount of aggregates can be arranged on the surface of the toner base particles, so that the liberation amount of the external additive can be optimized, the occurrence of filming can be suppressed, and the low-temperature fixability and low-temperature fixability can be reduced. It has been found that excellent cleaning performance due to adhesion can be achieved at a high level.

Therefore, in the present invention, a toner having a plurality of fine resin particles observed with a scanning electron microscope (SEM) on the surface of toner base particles, wherein the toner contains at least a resin and a wax, and the resin When the major diameter of the smallest particle in the fine particles is R, and the resin fine particles satisfying the major diameter of 3R or more are aggregated, the percentage of the surface of the toner base particles occupied by the aggregates is 15% or more and 60% or less. In addition to suppressing the occurrence of filming, it is possible to achieve both low-temperature fixability and excellent cleanability due to low adhesion at a high level.

<Resin fine particles>
The fine resin particles and aggregates composed of the fine resin particles in the present invention exist on the surfaces of the toner base particles, which will be described later.

The fine resin particles preferably have a core resin (core portion) and a shell resin (outer shell portion) covering at least a part of the surface of the core resin, and more preferably consist of the core resin and the shell resin. , a core resin and a shell resin.
The shell resin and the core resin preferably contain polymers obtained by homopolymerizing or copolymerizing vinyl monomers. The shell resin preferably contains a styrene-acrylic resin.
In the present invention, the shell resin may be referred to as "resin (b1)" and the core resin may be referred to as "resin (b2)".
In the present invention, particles containing the resin (b1) and the resin (b2) as constituent components in the same particle may be referred to as "resin fine particles (B)".

The vinyl monomer is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include the following (1) to (10).

(1) Vinyl hydrocarbons Examples of the vinyl hydrocarbons include (1-1) aliphatic vinyl hydrocarbons, (1-2) alicyclic vinyl hydrocarbons, and (1-3) aromatic vinyl hydrocarbons. mentioned.

(1-1) Aliphatic Vinyl Hydrocarbon Examples of the aliphatic vinyl hydrocarbon include alkenes and alkadienes.
Specific examples of the alkenes include ethylene, propylene and α-olefins.
Specific examples of the alkadiene include butadiene, isoprene, 1,4-pentadiene, 1,6-hexadiene, and 1,7-octadiene.

(1-2) Alicyclic Vinyl Hydrocarbons Examples of the alicyclic vinyl hydrocarbons include mono-cycloalkenes, di-cycloalkenes and alkadienes.
Specific examples of the alicyclic vinyl hydrocarbon include (di)cyclopentadiene and terpene.

(1-3) Aromatic Vinyl Hydrocarbon Examples of the aromatic vinyl hydrocarbon include styrene and its hydrocarbyl (alkyl, cycloalkyl, aralkyl and/or alkenyl)-substituted products.
Specific examples of the aromatic vinyl hydrocarbons include α-methylstyrene, 2,4-dimethylstyrene and vinylnaphthalene.

(2) Carboxyl Group-Containing Vinyl Monomers and Their Salts Examples of the carboxyl group-containing vinyl monomers and their salts include unsaturated monocarboxylic acids (salts) having 3 to 30 carbon atoms, unsaturated dicarboxylic acids (salts), and these. Anhydrides (salts), and monoalkyl (C1-24) esters thereof or salts thereof are included.
Specific examples of the carboxyl group-containing vinyl monomers and salts thereof include (meth)acrylic acid, (anhydrous) maleic acid, maleic acid monoalkyl ester, fumaric acid, fumaric acid monoalkyl ester, crotonic acid, itaconic acid, and itaconic acid. carboxyl group-containing vinyl monomers such as monoalkyl esters, glycol monoether itaconate, citraconic acid, monoalkyl citraconic acid, cinnamic acid, and metal salts thereof;

In the present invention, "(salt)" means an acid or a salt thereof.
For example, an unsaturated monocarboxylic acid (salt) having 3 to 30 carbon atoms means an unsaturated monocarboxylic acid or a salt thereof.
In the present invention, "(meth)acrylic" means methacrylic acid or acrylic acid.
In the present invention, "(meth)acryloyl" means methacryloyl or acryloyl.
In the present invention, "(meth)acrylate" means methacrylate or acrylate.

(3) Sulfone Group-Containing Vinyl Monomers, Vinyl Sulfate Monoesters, and Salts Thereof Examples of the sulfone group-containing vinyl monomers, vinyl sulfate monoesters, and salts thereof include alkene sulfonic acids having 2 to 14 carbon atoms. (salts), alkylsulfonic acid (salts) having 2 to 24 carbon atoms, sulfo(hydroxy)alkyl-(meth)acrylate (salts) or (meth)acrylamide (salts), alkylarylsulfosuccinic acid (salts), and the like. .
Specific examples of the alkenesulfonic acid (salt) having 2 to 14 carbon atoms include vinylsulfonic acid (salt).
Specific examples of the alkylsulfonic acid (salt) having 2 to 24 carbon atoms include α-methylstyrenesulfonic acid (salt).
Specific examples of the sulfo(hydroxy)alkyl-(meth)acrylate (salt) or (meth)acrylamide (salt) include sulfopropyl (meth)acrylate (salt), sulfate ester (salt), and sulfonic acid group-containing vinyl monomer. (salt) and the like.

(4) Phosphate group-containing vinyl monomer and its salt Examples of the phosphate group-containing vinyl monomer and its salt include (meth)acryloyloxyalkyl (C1-24) monoester (salt) of phosphate, (meth)acryloyloxy Alkyl (C 1-24) phosphonic acid (salt) and the like can be mentioned.
Specific examples of the (meth)acryloyloxyalkyl (C 1-24) phosphoric acid monoester (salt) include 2-hydroxyethyl (meth)acryloyl phosphate (salt), phenyl-2-acryloyloxyethyl phosphate (salt ) and the like.
Specific examples of the (meth)acryloyloxyalkyl (C1-24) phosphonic acid (salt) include 2-acryloyloxyethylphosphonic acid (salt).

Examples of salts of (2) carboxyl group-containing vinyl monomer, (3) sulfone group-containing vinyl monomer and vinyl sulfate monoester, and (4) phosphoric acid group-containing vinyl monomer include alkali metal salts (sodium salt, potassium salts, etc.), alkaline earth metal salts (calcium salts, magnesium salts, etc.), ammonium salts, amine salts, quaternary ammonium salts and the like.

(5) Hydroxyl Group-Containing Vinyl Monomer Examples of the hydroxyl group-containing vinyl monomer include hydroxystyrene, N-methylol(meth)acrylamide, hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, and polyethylene glycol mono(meth)acrylate. Acrylate, (meth)allyl alcohol, crotyl alcohol, isocrotyl alcohol, 1-buten-3-ol, 2-buten-1-ol, 2-butene-1,4-diol, propargyl alcohol, 2-hydroxyethyl propenyl ether, sucrose allyl ether and the like.

(6) Nitrogen-containing vinyl monomer Examples of the nitrogen-containing vinyl monomer include (6-1) amino group-containing vinyl monomer, (6-2) amide group-containing vinyl monomer, (6-3) nitrile group-containing vinyl monomer, (6-4) quaternary ammonium cationic group-containing vinyl monomers, (6-5) nitro group-containing vinyl monomers, and the like.

(6-1) Amino Group-Containing Vinyl Monomer Examples of the amino group-containing vinyl monomer include aminoethyl (meth)acrylate.

(6-2) Amide Group-Containing Vinyl Monomer Examples of the amide group-containing vinyl monomer include (meth)acrylamide and N-methyl(meth)acrylamide.

(6-3) Nitrile Group-Containing Vinyl Monomer Examples of the nitrile group-containing vinyl monomer include (meth)acrylonitrile, cyanostyrene, and cyanoacrylate.

(6-4) Quaternary ammonium cationic group-containing vinyl monomer Examples of the quaternary ammonium cationic group-containing vinyl monomer include dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylamide, quaternized products of tertiary amine group-containing vinyl monomers such as diethylaminoethyl (meth)acrylamide and diallylamine (those quaternized using a quaternizing agent such as methyl chloride, dimethyl sulfate, benzyl chloride and dimethyl carbonate); mentioned.

(6-5) Nitro Group-Containing Vinyl Monomer Examples of the nitro group-containing vinyl monomer include nitrostyrene.

(7) Epoxy Group-Containing Vinyl Monomer Examples of the epoxy group-containing vinyl monomer include glycidyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, and p-vinylphenylphenyl oxide.

(8) Halogen Element-Containing Vinyl Monomer Examples of the halogen element-containing vinyl monomer include vinyl chloride, vinyl bromide, vinylidene chloride, allyl chloride, chlorostyrene, bromostyrene, dichlorostyrene, chloromethylstyrene, tetrafluorostyrene, and chloroprene.

(9) Vinyl esters, vinyl (thio) ethers, vinyl ketones Examples of the vinyl esters include vinyl acetate, vinyl butyrate, vinyl propionate, vinyl butyrate, diallyl phthalate, diallyl adipate, isopropenyl acetate, vinyl methacrylate, and methyl 4. - vinyl benzoate, cyclohexyl methacrylate, benzyl methacrylate, phenyl (meth) acrylate, vinyl methoxy acetate, vinyl benzoate, ethyl α-ethoxy acrylate, alkyl (meth) acrylate having an alkyl group having 1 to 50 carbon atoms [methyl (meth) acrylate , ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate , eicosyl (meth)acrylate, behenyl (meth)acrylate, etc.)], dialkyl fumarate (wherein the two alkyl groups have 2 to 8 carbon atoms and are linear, branched or alicyclic groups) , dialkyl maleates (two alkyl groups have 2 to 8 carbon atoms and are linear, branched or alicyclic groups), poly(meth)allyloxyalkanes [diallyloxyethane, triaryl oxyethane, tetraallyloxyethane, tetraallyloxypropane, tetraallyloxybutane, tetrametaallyloxyethane, etc.], a vinyl monomer having a polyalkylene glycol chain [polyethylene glycol (molecular weight 300) mono(meth)acrylate, polypropylene glycol ( Molecular weight 500) monoacrylate, methyl alcohol ethylene oxide 10 mol adduct (meth)acrylate, lauryl alcohol ethylene oxide 30 mol adduct (meth)acrylate, etc.], poly(meth)acrylate [poly(meth)acrylate of polyhydric alcohol: ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, polyethylene glycol di(meth)acrylate, etc.].
Examples of the vinyl (thio)ether include vinyl methyl ether.
Examples of the vinyl ketone include vinyl methyl ketone.

(10) Other Vinyl Monomers Examples of the other vinyl monomers include tetrafluoroethylene, fluoroacrylate, isocyanatoethyl (meth)acrylate, m-isopropenyl-α,α-dimethylbenzyl isocyanate and the like.

In synthesizing the resin (b1), the above vinyl monomers (1) to (10) may be used singly or in combination of two or more.
The resin (b1) is not particularly limited and can be appropriately selected depending on the intended purpose. is more preferred, and a styrene-(meth)acrylic acid ester copolymer is even more preferred.
When the resin (b1) contains a carboxylic acid, it is possible to impart an acid value to the resin, which facilitates the formation of a toner having the fine resin particles (B) on the surfaces of toner base particles, which will be described later.

In synthesizing the resin (b2), one of the vinyl monomers (1) to (10) listed for the resin (b1) may be used alone, or two or more thereof may be used in combination. .
The resin (b2) is not particularly limited and can be appropriately selected depending on the intended purpose. is preferred, and a styrene-(meth)acrylate copolymer is more preferred.

The loss elastic modulus G″ of the viscoelastic properties of the resin (b1) at a frequency of 1 Hz and 100° C. is not particularly limited and can be appropriately selected depending on the purpose. ~30 MPa is more preferable, and 2.0 MPa to 10 MPa is even more preferable.
The loss elastic modulus G″ of the viscoelastic properties of the resin (b2) at a frequency of 1 Hz and 100° C. is not particularly limited and can be appropriately selected depending on the purpose. 0.02 MPa to 0.5 MPa is more preferred, and 0.05 MPa to 0.3 MPa is even more preferred.
When the loss elastic modulus G″ of the viscoelastic properties of the resin (b1) and the resin (b2) is within the above range, it becomes easier to form a toner having the fine resin particles (B) on the surfaces of toner base particles, which will be described later. .

The loss elastic modulus G″ of the viscoelastic properties in the present invention is measured under the following conditions using, for example, a viscoelasticity measuring device (ARES-24A (manufactured by Rheometric Co.)).
-Measurement condition-
・Jig: 25mm parallel plate ・Frequency: 1Hz
・Distortion rate: 10%
・Temperature increase rate: 5°C/min

The loss elastic modulus G″ of the viscoelastic properties of the resin (b1) and the resin (b2) at a frequency of 1 Hz and 100 ° C. is determined by the type and composition ratio of the constituent monomers, and the polymerization conditions (initiator, chain transfer agent, etc.) It is possible to adjust each loss modulus G″ within the above-described range depending on the type, amount used, reaction temperature, etc.).
Specific examples of methods for preparing the loss modulus G″ of the viscoelastic properties include (i) preparation of the glass transition temperature (Tg) and (ii) preparation of the calculated acid value (AV).

(i) Preparation of glass transition temperature (Tg) In the present specification, the glass transition temperature (Tg1) calculated from the constituent monomers of the resin (b1) is calculated from the constituent monomers of the resin (b2). (Tg2) is the glass transition temperature.
The glass transition temperature (Tg1) is preferably 0°C to 150°C, more preferably 50°C to 100°C.
When the glass transition temperature (Tg1) is 0° C. or higher, a toner having excellent heat-resistant storage stability can be obtained, which is preferable. When the glass transition temperature (Tg1) is 150° C. or less, it is preferable because there is little inhibition of heat conduction during fixing of the toner.
The glass transition temperature (Tg2) is preferably -30°C to 100°C, more preferably 0°C to 80°C, and still more preferably 30°C to 60°C.
When the glass transition temperature (Tg2) is −30° C. or higher, a toner excellent in heat-resistant storage stability can be obtained. When the glass transition temperature (Tg2) is 100° C. or less, it is preferable because the heat conduction is less inhibited during fixing of the toner.

The (Tg1) is preferably higher than the (Tg2), more preferably the (Tg1) is higher than the (Tg2) by 10° C. or more, and the (Tg1) is 20° C. higher than the (Tg2). ° C. or more is more preferable. By doing so, it is possible to easily form a toner having the fine resin particles (B) on the surface of the toner base particles described later, and to obtain a toner exhibiting excellent low-temperature fixability, which is preferable.

The glass transition temperature (Tg) calculated from the constituent monomers of the resin is a value that can be calculated by the Fox method.
Here, the Fox method [T. G. Fox, Phys. Rev. , 86, 652 (1952)] is a method for estimating the Tg of a copolymer from the Tg of individual homopolymers represented by the following (Equation 1).
1/Tg=W1/Tg1+W2/Tg2+...+Wn/Tgn (Formula 1)
(In Formula 1, Tg indicates the glass transition temperature of the copolymer (absolute temperature display), and Tg1, Tg2 ... Tgn is the glass transition temperature of the homopolymer of each monomer component (absolute temperature display). and W1, W2 . . . Wn represent the weight fraction of each monomer component).
The glass transition temperature (Tg) can be measured by the method (DSC) specified in ASTM D3418-82 using "DSC20, SSC/580" (manufactured by Seiko Instruments Inc.).

(ii) Preparation of calculated acid value (AV) In this specification, the calculated acid value of the resin (b1) is defined as (AV1), and the calculated acid value of the resin (b2) is defined as (AV2).
The (AV1) is preferably 75 mgKOH/g to 400 mgKOH/g, more preferably 150 mgKOH/g to 300 mgKOH/g.
The (AV2) is preferably 0 mgKOH/g to 50 mgKOH/g, more preferably 0 mgKOH/g to 20 mgKOH/g, and even more preferably 0 mgKOH/g, from the viewpoint of obtaining a toner exhibiting excellent low-temperature fixability.
The (AV1) is 75 mgKOH/g or more and 400 mgKOH/g or less, and the (AV2) is 0 mgKOH/g or more and 50 mgKOH/g or less, so that the toner base particles described later have the fine resin particles (B) on their surfaces. It is suitable because it facilitates the formation of toner.
The calculated acid value is a theoretical acid value calculated from the molar amount of acidic groups contained in the constituent monomers and the total weight of the constituent monomers.
The method for measuring the acid value in the present invention is not particularly limited and can be appropriately selected according to the purpose.

As the resin (b1) satisfying the conditions (i) and (ii), for example, from the viewpoint of (Tg1) and copolymerizability with other monomers, based on the total mass of the resin (b1), Styrene as a constituent monomer is preferably 10% by mass to 80% by mass, more preferably 30% by mass to 60% by mass, methacrylic acid and / or acrylic acid, preferably a total of 10% by mass to 60% by mass, More preferably, a resin containing 30% by mass to 50% by mass in total is included.
As the resin (b2) satisfying the conditions (i) and (ii), for example, from the viewpoint of (Tg2) and copolymerizability with other monomers, based on the total mass of the resin (b2), Styrene as a constituent monomer is preferably 10% by mass to 100% by mass, more preferably 30% by mass to 90% by mass, methacrylic acid and / or acrylic acid, preferably a total of 0% by mass to 7.5% by mass %, more preferably 0% by mass to 2.5% by mass in total.

The solubility parameter (hereinafter sometimes abbreviated as SP value) of the resin (b1) is 9 (cal/cm 3 ) 1/2 to 13 (cal/cm ³ ) ^1/2 to 13 (cal/ cm ³ ) ^1/2 is preferable, 9.5 (cal/cm ³ ) ^1/2 to 12.5 (cal/cm ³ ) ^1/2 is more preferable, and 10.5 (cal/cm ³ ) ^1/2 is more preferable. ~11.5 (cal/cm ³ ) ^1/2 is more preferable.
The SP value of the resin (b2) is preferably 8.5 (cal/cm ³ ) ^1/2 to 12.5 (cal/cm ³ ) ^1/2 from the viewpoint of ease of forming toner particles. 9 (cal/cm ³ ) ^1/2 to 12 (cal/cm ³ ) ^1/2 is more preferable, and 10 (cal/cm ³ ) ^1/2 to 11 (cal/cm ³ ) ^1/2 is even more preferable.
The SP values of the resin (b1) and the resin (b2) can be adjusted by changing the types of constituent monomers and their composition ratios.
It should be noted that the SP value in the present invention is determined by the Fedors method [Polym. Eng. Sci. 14(2) 152, (1974)].

The number average molecular weight (Mn1) of the resin (b1) is not particularly limited and can be appropriately selected depending on the purpose. preferable. When the number average molecular weight (Mn1) is 2,000 or more, the heat resistant storage stability is improved, and when it is 2,000,000 or less, the low-temperature fixability of the toner is less hindered, which is preferable.
The number average molecular weight (Mn2) of the resin (b2) is not particularly limited and can be appropriately selected depending on the purpose. preferable. When the number average molecular weight (Mn2) is 1,000 or more, the heat-resistant storage stability of the toner is improved.

The weight-average molecular weight (Mw1) of the resin (b1) is not particularly limited and can be appropriately selected depending on the purpose. is more preferred. When the weight-average molecular weight (Mw1) is 20,000 or more, the heat-resistant storage stability of the toner is improved.
The weight-average molecular weight (Mw2) of the resin (b2) is not particularly limited and can be appropriately selected depending on the purpose. is more preferred. When the weight-average molecular weight (Mw2) is 10,000 or more, the heat-resistant storage stability of the toner is improved, and when it is 10,000,000 or less, the low-temperature fixability of the toner is less hindered, which is preferable.

The weight average molecular weight (Mw1) of the resin (b1) is preferably larger than the weight average molecular weight (Mw2) of the resin (b2), and is 1.5 times the weight average molecular weight (Mw2) of the resin (b2). It is more preferably at least 2.0 times the weight average molecular weight (Mw2) of the resin (b2). When the (Mw1) is within the above range, the toner having the fine resin particles (B) on the surface of the toner base particles, which will be described later, can be easily formed, and the toner exhibiting excellent low-temperature fixability can be obtained, which is preferable. .

Among these, the resin (b1) has a weight average molecular weight (Mw1) of 200,000 to 2,000,000, and the resin (b2) has a weight average molecular weight (Mw2) of 100,000 to 500,000. and "the weight average molecular weight (Mw1) of the resin (b1)" > "the weight average molecular weight (Mw2) of the resin (b2)".

The number average molecular weight (Mn) and weight average molecular weight (Mw) in the present invention can be measured using gel permeation chromatography (GPC) under the following conditions.
-Measurement condition-
・ Apparatus (one example): "HLC-8120" (manufactured by Tosoh Corporation)
・ Column (one example): 2 “TSK GEL GMH6” (manufactured by Tosoh Corporation) ・ Measurement temperature: 40 ° C.
・Sample solution: 0.25% by weight tetrahydrofuran solution (undissolved matter was filtered through a glass filter)
・Solution injection amount: 100 μl
・ Detector: Refractive index detector ・ Reference material: 12 standard polystyrene (TSK standard POLYSTYRENE) (molecular weight: 500, 1,050, 2,800, 5,970, 9,100, 18,100, 37,900, 96 , 400, 190,000, 355,000, 1,090,000, 2,890,000) (manufactured by Tosoh Corporation)

The mass ratio of the resin (b1) and the resin (b2) in the resin fine particles (B) [mass of the resin (b1)/mass of the resin (b2)] is not particularly limited, and may be appropriately selected according to the purpose. Although it can be selected, 5/95 to 95/5 is preferable, 25/75 to 75/25 is more preferable, and 40/60 to 60/40 is even more preferable.
When the mass ratio of the resin (b1) and the resin (b2) is 5/95 or more, the toner has excellent heat-resistant storage stability, and the mass ratio of the resin (b1) and the resin (b2) is 95/95. If it is 5 or less, the toner having the fine resin particles (B) on the surface of the toner base particles described below can be easily formed, which is preferable.

The content of the fine resin particles (B) (the sum of the masses of the resin (b1) and the resin (b2)) is 0.2% by mass or more and 5% by mass or less with respect to the toner. preferable. When the sum of the masses of the resin (b1) and the resin (b2) is within the above range, the low temperature fixability and the heat resistant storage stability are preferably improved.
When the content of the fine resin particles (B) is 0.2% by mass or more relative to the toner, it is possible to prevent problems such as deterioration of heat-resistant storage stability. When the amount is 5% by mass or less relative to the toner, it is possible to prevent problems such as deterioration of low-temperature fixability.

<Volume average primary particle size>
The volume-average primary particle size of the fine resin particles (B) is preferably 10 nm or more and 100 nm or less, more preferably 10 nm or more and 50 nm or less, from the viewpoint of obtaining a toner exhibiting good low-temperature fixability.
The volume-average primary particle size can be measured by, for example, scanning electron microscope (SEM) image observation or dynamic light scattering particle size distribution analyzer (LB).

In the toner of the present invention, the resin fine particles (B) can be used alone. It is preferable to use together with resin fine particles (A) composed of styrene-acrylic resin.
In the toner manufacturing process of the present invention, the resin fine particles (A) and the resin fine particles (B) previously mixed during emulsification uniformly adhered to the surface of the toner base particles, and then adhered to the toner surface in the washing step described later. By removing the resin fine particles (A) and all or part of the resin (b1) in the resin fine particles (B), the resin fine particles (B) can be attached with uniform gaps.
In the toner of the present invention, the mass ratio [(B)/(A)] of the fine resin particles (B) to the fine resin particles (A) is not particularly limited and can be appropriately selected depending on the intended purpose. 4 is preferred, and 1/2 is more preferred.

The method for producing the resin fine particles (B) is not particularly limited, and includes known production methods. For example, a method of forming a core resin and then forming a shell resin so as to cover the core resin, A method of forming a core resin in the shell resin after forming the shell resin can be used.
Although the details of the mechanism in the method of forming the core resin in the shell resin after forming the shell resin described above are not clear, the hydrophobicity of the constituent monomers of the resin (b2) is adjusted so that the resin ( It is thought that the resin (b2) can be synthesized into the resin (b1) by making the resin (b1) more compatible with the resin (b1) and allowing the resin (b1) to absorb the constituent monomers of the resin (b2).
Specific examples of the method for producing the resin fine particles (B) include the following production methods (I) to (V). Any of the following production methods (I) to (V) can be suitably employed.

(I) A method of seed-polymerizing the constituent monomers of the resin (b2) using the resin (b1) in the aqueous dispersion as a seed. After producing an aqueous dispersion of particles containing the resin (b1), a method of seed-polymerizing the constituent monomers of the resin (b2) using this as a seed, and a method of emulsifying and dispersing the resin (b1) previously produced by solution polymerization or the like in water. After that, using this as a seed, the constituent monomers of the resin (b2) are subjected to seed polymerization.

(II) A method of seed-polymerizing the constituent monomers of the resin (b1) using the resin (b2) in the aqueous dispersion as a seed. After producing an aqueous dispersion of particles containing the resin (b2), a method of seed-polymerizing the constituent monomers of the resin (b1) using this as a seed, and a method of emulsifying and dispersing the resin (b2) previously produced by solution polymerization or the like in water. After that, using this as a seed, the constituent monomers of the resin (b1) are subjected to seed polymerization.

(III) A method of obtaining an aqueous dispersion of fine resin particles by emulsifying a mixture of the resin (b1) and the resin (b2) in an aqueous medium. ) and the resin (b2) in solution or melt, and then emulsifying and dispersing this mixture in an aqueous medium.

(IV) A method of emulsifying a mixture of the resin (b1) and the monomers constituting the resin (b2) in an aqueous medium and then polymerizing the monomers constituting the resin (b2) to obtain an aqueous dispersion of fine resin particles. As a specific example of , the resin (b1) prepared in advance by solution polymerization or the like is mixed with the constituent monomers of the resin (b2), emulsified and dispersed in an aqueous medium, and then the constituent monomers of the resin (b2) are polymerized. and a method of producing the resin (b1) in the constituent monomers of the resin (b2), emulsifying and dispersing the mixture in an aqueous medium, and then polymerizing the constituent monomers of the resin (b2).

(V) A method of emulsifying a mixture of the resin (b2) and the constituent monomers of the resin (b1) in an aqueous medium and then polymerizing the constituent monomers of the resin (b1) to obtain an aqueous dispersion of fine resin particles. As a specific example of , the resin (b2) prepared in advance by solution polymerization or the like is mixed with the constituent monomers of the resin (b1), emulsified and dispersed in an aqueous medium, and then the constituent monomers of the resin (b1) are polymerized. and a method of producing the resin (b2) in the constituent monomers of the resin (b1), emulsifying and dispersing the mixture in an aqueous medium, and then polymerizing the constituent monomers of the resin (b1).

The fact that the resin fine particles (B) contain the resin (b1) and the resin (b2) in the same particle as constituent components means that the cut surface of the resin fine particles (B) is analyzed by a known surface elemental analyzer (TOF). - SIMSEDX-SEM, etc.), and observation of the cut surface of the resin fine particles (B) stained with a staining agent corresponding to the functional groups contained in the resin (b1) and the resin (b2). It can be confirmed by observing an electron microscope observation image.
Further, the resin fine particles obtained by this method comprise only the resin (b1) in addition to the resin fine particles (B) containing the resin (b1) and the resin (b2) as constituent components in the same particle. It may be obtained as a mixture containing resin fine particles as a resin component and resin fine particles having only the resin (b2) as a constituent resin component. Only the resin fine particles (B) may be isolated and used.

The fine resin particles (B) are preferably used as an aqueous dispersion.
The substance (aqueous medium) used in the aqueous dispersion is not particularly limited as long as it is soluble in water, and can be appropriately selected according to the purpose. colloids and the like. These may be used individually by 1 type, and may use 2 or more types together.
Moreover, as the aqueous medium used for the aqueous dispersion, any liquid essentially containing water can be used without particular limitation, and examples thereof include an aqueous solution containing water.

-Surfactant (D)-
The surfactant (D) is not particularly limited and can be appropriately selected depending on the intended purpose. ), amphoteric surfactants (D4), and other emulsifying dispersants (D5).

The nonionic surfactant (D1) is not particularly limited and can be appropriately selected depending on the intended purpose. are mentioned.
Examples of the AO addition type nonionic surfactants include, for example, EO adducts of aliphatic alcohols having 10 to 20 carbon atoms, EO adducts of phenol, EO (ethylene oxide) adducts of nonylphenol, Examples include EO adducts of alkylamines and EO adducts of poly(oxypropylene) glycol.
Examples of the polyhydric alcohol-type nonionic surfactant include, for example, fatty acid (8 to 24 carbon atoms) esters of polyhydric (3 to 8 or more) alcohols (2 to 30 carbon atoms) (eg, glycerol monostearate monooleate, glycerin monooleate, sorbitan monolaurate, sorbitan monooleate, etc.), alkyl (C4-24) poly(polymerization degree 1-10) glycosides, and the like.

The anionic surfactant (D2) is not particularly limited and can be appropriately selected depending on the purpose. Sulfuric acid esters or ether sulfate esters having a hydrocarbon group of and salts thereof, sulfonates having a hydrocarbon group of 8 to 24 carbon atoms, sulfosuccinic acid having 1 or 2 hydrocarbon groups of 8 to 24 carbon atoms salts, phosphates or ether phosphates having a hydrocarbon group of 8 to 24 carbon atoms and salts thereof, fatty acid salts having a hydrocarbon group of 8 to 24 carbon atoms, and hydrocarbon groups of 8 to 24 carbon atoms and acylated amino acid salts having
Examples of the ether carboxylic acid having a hydrocarbon group of 8 to 24 carbon atoms or salts thereof include sodium lauryl ether acetate, (poly)oxyethylene (addition mole number 1 to 100) sodium lauryl ether acetate, and the like.
Examples of the sulfuric acid ester or ether sulfuric acid ester having a hydrocarbon group having 8 to 24 carbon atoms or salts thereof include sodium lauryl sulfate, (poly)oxyethylene (addition mole number 1 to 100) sodium lauryl sulfate, (poly ) oxyethylene (addition mole number 1 to 100) lauryl sulfate triethanolamine, (poly)oxyethylene (addition mole number 1 to 100) coconut oil fatty acid monoethanolamide sodium sulfate, and the like.
Examples of the sulfonate having a hydrocarbon group of 8 to 24 carbon atoms include sodium dodecylbenzenesulfonate.
Examples of the phosphate ester or ether phosphate ester having a hydrocarbon group of 8 to 24 carbon atoms or salts thereof include sodium lauryl phosphate, (poly)oxyethylene (addition mole number 1 to 100) lauryl ether phosphorus acid sodium salt, and the like.
Examples of fatty acid salts having a hydrocarbon group of 8 to 24 carbon atoms include sodium laurate and triethanolamine laurate.
Examples of the acylated amino acid salt having a hydrocarbon group having 8 to 24 carbon atoms include sodium cocoate methyltaurate, sodium cocoate sarcosine, cocoate sarcosine triethanolamine, and N-cocoate acyl-L. -Triethanolamine glutamic acid, sodium N-coconut fatty acid acyl-L-glutamate, sodium lauroylmethyl-β-alanine and the like.

The cationic surfactant (D3) is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include quaternary ammonium salt type and amine salt type.
Examples of the quaternary ammonium salt type include stearyltrimethylammonium chloride, behenyltrimethylammonium chloride, distearyldimethylammonium chloride, lanolin fatty acid aminopropylethyldimethylammonium ethyl sulfate, and the like.
Examples of the amine salt type include stearic acid diethylaminoethylamide lactate, dilaurylamine hydrochloride, and oleylamine lactate.

The amphoteric surfactant (D4) is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include betaine amphoteric surfactants and amino acid amphoteric surfactants.
Examples of the betaine-type amphoteric surfactant include coconut oil fatty acid amidopropyldimethylaminoacetate betaine, lauryldimethylaminoacetate betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, and laurylhydroxysulfobetaine. etc.
Examples of the amino acid type amphoteric surfactant include sodium β-laurylaminopropionate.

The other emulsifying dispersant (D5) is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include reactive activators.
The reactive activator is not particularly limited as long as it has radical reactivity, and can be appropriately selected according to the purpose. 20, SR-30, ER-20, ER-30 (above, manufactured by ADEKA Co., Ltd.), Aqualon (registered trademark) HS-10, KH-05, KH-10, KH-1025 (above, Daiichi Kogyo Seiyaku Co., Ltd. company), Eleminol (registered trademark) JS-20 (manufactured by Sanyo Chemical Industries, Ltd.), Latemul (registered trademark) D-104, PD-420, PD-430 (manufactured by Kao Corporation), Ionet (registered trademark) ) MO-200 (manufactured by Sanyo Chemical Industries, Ltd.), polyvinyl alcohol, starch or derivatives thereof, cellulose derivatives such as carboxymethylcellulose, methylcellulose and hydroxyethylcellulose, and carboxyl group-containing (co)polymers such as sodium polyacrylate and the United States Examples thereof include emulsifying dispersants having a urethane group or an ester group described in Japanese Patent No. 5906704 (for example, polycaprolactone polyol and polyether diol linked with polyisocyanate).

The surfactant (D) includes a nonionic surfactant (D1) and an anion from the viewpoint of stabilizing the oil droplets during emulsification and dispersion, obtaining a desired shape, and sharpening the particle size distribution. A combination of a surfactant (D2) and another emulsifying dispersant (D5) is preferred, a combination of a nonionic surfactant (D1) and another emulsifying dispersant (D5), and an anionic surfactant ( Combination use of D2) with another emulsifying dispersant (D5) is more preferred.

―Buffer―
The buffering agent is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include sodium acetate, sodium citrate, sodium bicarbonate and the like.

―Protective Colloid―
The protective colloid is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include water-soluble cellulose compounds and alkali metal salts of polymethacrylic acid.

In addition to the resin (b1) and the resin (b2), the resin fine particles (B) include other resin components, an initiator (and its residue), a chain transfer agent, an antioxidant, a plasticizer, a preservative, and a reducing agent. It may contain an agent, an organic solvent, and the like.

-Other resin components-
The other resin component is not particularly limited and can be appropriately selected depending on the intended purpose. Resins, polyamide resins, polyimide resins, silicon resins, phenol resins, melamine resins, urea resins, aniline resins, ionomer resins, polycarbonate resins and the like.

-Initiator (and its residue)-
The initiator (and its residue) is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include known radical polymerization initiators.
Specific examples of the initiators (and residues thereof) include persulfate initiators such as potassium persulfate and ammonium persulfate; azo initiators such as azobisisobutyronitrile; benzoyl peroxide, cumene hydroperoxide, tarsier Organic peroxides such as butyl hydroperoxide, tert-butyl peroxyisopropyl monocarbonate and tert-butyl peroxybenzoate; and hydrogen peroxide.

-Chain transfer agent-
The chain transfer agent is not particularly limited and can be appropriately selected depending on the intended purpose. -Mercaptopropionic acid, α-methylstyrene dimer, and the like.

-Antioxidant-
The antioxidant is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include phenol compounds, paraphenylenediamine, hydroquinone, organic sulfur compounds, organic phosphorus compounds and the like.

Examples of the phenol compound include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, stearyl-β-(3,5 -di-t-butyl-4-hydroxyphenyl)propionate, 2,2'-methylene-bis-(4-methyl-6-t-butylphenol), 2,2'-methylene-bis-(4-ethyl-6 -t-butylphenol), 4,4'-thiobis-(3-methyl-6-t-butylphenol), 4,4'-butylidenebis-(3-methyl-6-t-butylphenol), 1,1,3- Tris-(2-methyl-4-hydroxy-5-t-butylphenyl)butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl ) benzene, tetrakis-[methylene-3-(3′,5′-di-t-butyl-4′-hydroxyphenyl)propionate]methane, bis[3,3′-bis(4′-hydroxy-3′- t-butylphenyl)butyric acid]glycol ester, tocopherol and the like.

Examples of the paraphenylenediamine include N-phenyl-N'-isopropyl-p-phenylenediamine, N,N'-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl-p -phenylenediamine, N,N'-di-isopropyl-p-phenylenediamine, N,N'-dimethyl-N,N'-di-t-butyl-p-phenylenediamine and the like.

Examples of the hydroquinone include 2,5-di-t-octylhydroquinone, 2,6-didodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, and 2-t-octyl-5-methylhydroquinone. , 2-(2-octadecenyl)-5-methylhydroquinone, and the like.

Examples of the organic sulfur compounds include dilauryl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate and ditetradecyl-3,3'-thiodipropionate.

Examples of the organic phosphorus compounds include triphenylphosphine, tri(nonylphenyl)phosphine, tri(dinonylphenyl)phosphine, tricresylphosphine, and tri(2,4-dibutylphenoxy)phosphine.

―Plasticizer―
The plasticizer is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include phthalates, aliphatic dibasic acid esters, trimellitates, phosphates and fatty acid esters.

Examples of the phthalates include dibutyl phthalate, dioctyl phthalate, butyl benzyl phthalate, and diisodecyl phthalate.

Examples of the aliphatic dibasic acid esters include di-2-ethylhexyl adipate and 2-ethylhexyl sebacate.

Examples of the trimellitate include tri-2-ethylhexyl trimellitate and trioctyl trimellitate.

Examples of the phosphate include triethyl phosphate, tri-2-ethylhexyl phosphate, and tricresyl phosphate.

Examples of the fatty acid ester include butyl oleate.

-Preservative-
The preservative is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include organic nitrogen-sulfur compound preservatives and organic sulfur halide preservatives.

-Reducing agent-
The reducing agent is not particularly limited and can be appropriately selected depending on the purpose. Examples include reducing organic compounds such as ascorbic acid, tartaric acid, citric acid, glucose, and formaldehyde sulfoxylate metal salts; , sodium bisulfite, and reducing inorganic compounds such as sodium metabisulfite.

-Organic solvent-
The organic solvent is not particularly limited and can be appropriately selected depending on the purpose. Examples include ketone solvents such as acetone and methyl ethyl ketone (hereinafter abbreviated as MEK); ester solvents such as ethyl acetate and γ-butyrolactone; ) and other ether solvents; N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam and other amide solvents; isopropyl alcohol and other alcohol solvents; toluene, xylene and other aromatics group hydrocarbon solvents and the like.

<Toner base particles>
The toner base particles (hereinafter sometimes referred to as "toner base particles" or "base particles") contain a binder resin, a colorant, and a wax, and if necessary, other components (B). contains.

<<Binder Resin>>
The binder resin is not particularly limited and can be appropriately selected depending on the purpose. Examples include polyester resin, styrene-acrylic resin, polyol resin, vinyl resin, polyurethane resin, epoxy resin, polyamide resin, polyimide Resins, silicon-based resins, phenolic resins, melamine resins, urea resins, aniline resins, ionomer resins, polycarbonate resins, and the like. Among these, the polyester resin is preferable because it can impart flexibility to the toner.
These may be used individually by 1 type, and may use 2 or more types together.

<<<polyester resin>>>
The polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include crystalline polyester resins, amorphous polyester resins, and modified polyester resins.
These may be used individually by 1 type, and may use 2 or more types together.

-Crystalline Polyester-
The crystalline polyester resin (hereinafter also referred to as "crystalline polyester" or "polyester resin component D") is not particularly limited and can be appropriately selected depending on the purpose. and a crystalline polyester resin obtained by reacting with.

Since the crystalline polyester resin has high crystallinity, it exhibits a heat melting characteristic that exhibits a rapid viscosity drop near the fixing start temperature.
By using the crystalline polyester resin having such properties in combination with the amorphous polyester resin described later, the heat resistance storage stability due to the crystallinity is good until just before the melting start temperature, and the crystalline polyester resin melts at the melting start temperature. causes a sharp drop in viscosity (sharp melt), and along with that, it is compatible with the amorphous polyester resin, and both are fixed by a sharp drop in viscosity, so both good heat-resistant storage stability and low-temperature fixability are achieved. toner is obtained. Good results are also obtained with respect to the release width (difference between minimum fixing temperature and high-temperature offset generating temperature).
In the present invention, the crystalline polyester resin refers to those obtained by reacting a polyol with a polycarboxylic acid as described above, and modified polyester resins such as the above prepolymers and prepolymers thereof. does not belong to the above crystalline polyester resins.

--polyol--
The polyol used for synthesizing the crystalline polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include diols and trihydric or higher alcohols.

Examples of the diol used for synthesizing the crystalline polyester resin include saturated aliphatic diols.
Examples of the saturated aliphatic diols include linear saturated aliphatic diols and branched saturated aliphatic diols. Among these, straight-chain saturated aliphatic diols are preferable, and straight-chain saturated aliphatic diols having 2 or more and 12 or less carbon atoms are more preferable, because they can improve crystallinity and prevent a decrease in melting point.
These may be used individually by 1 type, and may use 2 or more types together.

Specific examples of the saturated aliphatic diols include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1 ,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1 , 18-octadecanediol, 1,14-eicosanediol, and the like. Among these, ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,10 -decanediol, 1,12-dodecanediol are preferred.

Examples of the trihydric or higher alcohol used for synthesizing the crystalline polyester resin include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol.

-- Polycarboxylic acid --
The polycarboxylic acid used for synthesizing the crystalline polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose. be done.

Examples of the divalent carboxylic acid used in the synthesis of the crystalline polyester resin include oxalic acid, succinic acid, glutaric acid, adipic acid, spelic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, Saturated aliphatic dicarboxylic acids such as 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid; phthalic acid, isophthalic acid, terephthalic acid, naphthalene- Aromatic dicarboxylic acids such as dibasic acids such as 2,6-dicarboxylic acid, malonic acid, and mesaconic acid, and the like, as well as their anhydrides and their lower (1 to 3 carbon atoms) alkyl esters. be done.

Examples of the trivalent or higher carboxylic acid used for synthesizing the crystalline polyester resin include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, and 1,2,4-naphthalenetricarboxylic acid. Acids, their anhydrides, their lower alkyl esters (having 1 to 3 carbon atoms) and the like.

Examples of the polycarboxylic acid used for synthesizing the crystalline polyester resin include, in addition to the saturated aliphatic dicarboxylic acid and aromatic dicarboxylic acid, a dicarboxylic acid having a sulfonic acid group, a dicarboxylic acid having a double bond, and the like. may be included.
These may be used individually by 1 type, and may use 2 or more types together.

The crystalline polyester resin is preferably composed of a linear saturated aliphatic dicarboxylic acid having 4 to 12 carbon atoms and a linear saturated aliphatic diol having 2 to 12 carbon atoms. That is, the crystalline polyester resin preferably has a structural unit derived from a saturated aliphatic dicarboxylic acid having 4 to 12 carbon atoms and a structural unit derived from a saturated aliphatic diol having 2 to 12 carbon atoms. . By doing so, the crystallinity is high and the sharp melt property is excellent, which is preferable in that excellent low-temperature fixability can be exhibited.

The presence or absence of crystallinity of the crystalline polyester resin in the toner of the present invention can be confirmed by a crystal analysis X-ray diffraction device (for example, X'Pert Pro MRD, manufactured by Philips). The measurement method will be described below.
First, a target sample is ground in a mortar to prepare a sample powder, and the obtained sample powder is uniformly applied to a sample holder. After that, the sample holder is set in the diffractometer, measurement is performed, and a diffraction spectrum is obtained.
In the obtained diffraction spectrum, when the peak half width of the peak with the highest peak intensity among the peaks obtained in the range of 20 ° <2θ < 25 ° is 2.0 or less, it is said to have a crystalline polyester resin. It was judged.
In the present invention, a polyester resin that does not exhibit the above-described state as opposed to a crystalline polyester resin is defined as an amorphous polyester resin.
The measurement conditions for X-ray diffraction are described below.
-Measurement condition-
・Tension kV: 45 kV
・Current: 40mA
・MPSS
・Upper
・Gonio
・Scan mode: continuous
・Start angle: 3°
・End angle: 35°
・Angle Step: 0.02°
・Lucident beam optics
・Divergence slit: Div slit 1/2
・Diflection beam optics
・Anti scatter slit: As Fixed 1/2
・Receiving slit: Prog rec slit

The melting point of the crystalline polyester resin is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 60° C. or higher and 80° C. or lower.
When the melting point of the crystalline polyester resin is 60° C. or higher, the crystalline polyester resin is easily melted at a low temperature, and the problem of deterioration of the heat-resistant storage stability of the toner can be prevented. It is possible to prevent the problem of insufficient low-temperature fixability due to insufficient melting of the crystalline polyester resin by heating.

The molecular weight of the crystalline polyester resin is not particularly limited and can be appropriately selected depending on the purpose.
The weight-average molecular weight (Mw) of the soluble portion of ortho-dichlorobenzene in the crystalline polyester resin is preferably 3,000 to 30,000, more preferably 5,000 to 15,000, as measured by GPC.
The number-average molecular weight (Mn) of the ortho-dichlorobenzene-soluble portion of the crystalline polyester resin is preferably 1,000 to 10,000, more preferably 2,000 to 10,000, as measured by GPC.
The molecular weight ratio (Mw/Mn) of the crystalline polyester resin is preferably 1.0 to 10, more preferably 1.0 to 5.0. This is because those having a sharp molecular weight distribution and a low molecular weight are excellent in low-temperature fixability, and the heat-resistant storage stability is lowered when there are many low-molecular-weight components.

The acid value of the crystalline polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose. , preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more. On the other hand, 45 mgKOH/g or less is preferable in order to improve high temperature offset resistance.

The hydroxyl value of the crystalline polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose. /g to 50 mgKOH/g, more preferably 5 mgKOH/g to 50 mgKOH/g.

The molecular structure of the crystalline polyester resin can be confirmed by X-ray diffraction, GC/MS, LC/MS, IR measurement, etc., in addition to NMR measurement using a solution or solid. A simple method is to detect a crystalline polyester resin having absorption based on δCH (out-of-plane bending vibration) of an olefin at 965±10 cm −1 or 990±10 cm −1 in the infrared absorption spectrum. .

The content of the crystalline polyester resin is not particularly limited and can be appropriately selected according to the intended purpose. Parts or more and 15 mass parts or less are more preferable.
When the content of the crystalline polyester resin is 3 parts by mass or more, sharp melting by the crystalline polyester resin is insufficient, and thus the problem of poor low-temperature fixability can be prevented. When the content of the crystalline polyester resin is 20 parts by mass or less, it is possible to prevent problems such as deterioration of heat-resistant storage stability and susceptibility to image fogging.

-Amorphous polyester resin-
The amorphous polyester resin (hereinafter sometimes referred to as "amorphous polyester", "amorphous polyester", "amorphous polyester resin", "unmodified polyester resin", and "polyester resin component A") is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include amorphous polyester resins obtained by reacting a polyol with a polycarboxylic acid.
In the present invention, the amorphous polyester resin is obtained by reacting a polyol and a polycarboxylic acid as described above. That is, modified polyester resins, for example, prepolymers described later and modified polyester resins obtained by cross-linking and/or elongation reactions of the prepolymers are not included in the amorphous polyester resins in the present invention. , treated as a modified polyester resin.
The amorphous polyester resin is a polyester resin component soluble in tetrahydrofuran (THF).
A linear polyester resin is preferable as the amorphous polyester resin.

--polyol--
Examples of polyols used for synthesizing the amorphous polyester resin include diols.

Examples of the diol used for synthesizing the amorphous polyester resin include polyoxypropylene (2.2)-2,2-bis(4-hydroxyphenyl)propane, polyoxyethylene (2.2)-2, 2-bis(4-hydroxyphenyl) propane and other alkylene (carbon number 2-3) oxide (average addition mole number 1-10) adducts of bisphenol A; ethylene glycol, propylene glycol; hydrogenated bisphenol A, hydrogenated bisphenol Examples include alkylene (carbon number 2-3) oxide (average addition mole number 1-10) adducts of A, and the like. Among these, the polyol preferably contains 40 mol % or more of alkylene glycol.
These may be used individually by 1 type, and may use 2 or more types together.

-- Polycarboxylic acid --
Examples of the polycarboxylic acid used for synthesizing the amorphous polyester resin include dicarboxylic acids.

Examples of the dicarboxylic acid used in the synthesis of the amorphous polyester resin include adipic acid, phthalic acid, isophthalic acid, terephthalic acid, fumaric acid, maleic acid, dodecenylsuccinic acid, octylsuccinic acid, and the like. and succinic acid substituted with an alkenyl group having 2 to 20 carbon atoms. Among these, polycarboxylic acids containing 50 mol % or more of terephthalic acid are preferred.
These may be used individually by 1 type, and may use 2 or more types together.

In order to adjust the acid value and hydroxyl value, the amorphous polyester resin has a trivalent or higher carboxylic acid and/or a trivalent or higher alcohol, or a trivalent or higher epoxy at the terminal of the resin chain in the amorphous polyester resin. Compounds and the like may be included. Among these, it is preferable to contain a trihydric or higher aliphatic alcohol from the viewpoint that unevenness is less likely to occur and sufficient gloss and image density can be obtained.
Examples of trivalent or higher carboxylic acids in the amorphous polyester resin include trimellitic acid, pyromellitic acid, and acid anhydrides thereof.
Examples of the trihydric or higher alcohol in the amorphous polyester resin include glycerin, pentaerythritol, and trimethylolpropane.

The molecular weight of the amorphous polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose, but is preferably within the following range.
The weight average molecular weight (Mw) of the amorphous polyester resin is preferably 3,000 to 10,000, more preferably 4,000 to 7,000.
The number average molecular weight (Mn) of the amorphous polyester resin is preferably 1,000 to 4,000, more preferably 1,500 to 3,000.
The molecular weight ratio (Mw/Mn) of the amorphous polyester resin is preferably 1.0 to 4.0, more preferably 1.0 to 3.5.
The reason why the weight average molecular weight (Mw) and the number average molecular weight (Mn) are preferably within the above ranges is that the weight average molecular weight (Mw) is less than 3,000 and the number average molecular weight (Mn) is 1,000. If it is less than 10,000, the heat-resistant storage stability of the toner and durability against stress such as agitation in the developing machine may be inferior, and the weight average molecular weight (Mw) is 10,000 and the number average molecular weight (Mn) is 4,000. , the viscoelasticity of the toner becomes high when it is melted, and the low-temperature fixability may be deteriorated.
The weight average molecular weight (Mw) and the number average molecular weight (Mn) can be measured, for example, by GPC (gel permeation chromatography).

The content of the component having a molecular weight of 600 or less in the amorphous polyester resin (THF-soluble component) is preferably 2% by mass to 10% by mass.
If the content of the component having a molecular weight of 600 or less in the amorphous polyester resin (THF-soluble component) is 10% by mass or less, problems such as poor heat-resistant storage stability of the toner and poor durability against stress such as agitation in the developing machine may occur. If the component having a molecular weight of 600 or less in the amorphous polyester resin (THF-soluble component) is 2% by mass or more, the problem of poor low-temperature fixability can be resolved.
As a method for adjusting the content of components having a molecular weight of 600 or less in the amorphous polyester resin (THF soluble matter), the amorphous polyester resin is extracted with methanol to remove components having a molecular weight of 600 or less, followed by purification. and methods to do so.

The acid value of the amorphous polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose.
When the acid value of the amorphous polyester resin is 1 mgKOH/g or more, the toner tends to be negatively charged, and the affinity between the toner and the paper is improved when the toner is fixed to the paper, thereby improving the low-temperature fixability. be able to. When the acid value of the amorphous polyester resin is 50 mgKOH/g or less, it is possible to prevent the problem of deterioration in charging stability, particularly against environmental fluctuations.

The hydroxyl value of the amorphous polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose, but is preferably 5 mgKOH/g or more.

The glass transition temperature (Tg) of the amorphous polyester resin is preferably 40°C to 65°C, more preferably 45°C to 65°C, even more preferably 50°C to 60°C.
When the Tg of the amorphous polyester resin is 40° C. or higher, the heat-resistant storage stability of the toner and the durability against stress such as agitation in the developing machine are improved, and the anti-filming property is improved, which is preferable. be. When the Tg of the amorphous polyester resin is 65° C. or less, the deformation due to heat and pressure during fixing of the toner is improved, and the low-temperature fixability is improved, which is preferable.

The content of the amorphous polyester resin is preferably 80 parts by mass or more and 90 parts by mass or less with respect to 100 parts by mass of the toner in that a toner having both low-temperature fixability and heat-resistant storage stability can be obtained.

-Modified polyester resin-
The modified polyester resin (hereinafter sometimes referred to as "modified polyester" or "polyester resin component C") is not particularly limited and can be appropriately selected depending on the purpose. and a polyester resin having a site capable of reacting with the active hydrogen group-containing compound (hereinafter sometimes referred to as "prepolymer" or "polyester prepolymer").
The modified polyester resin is a polyester resin insoluble in tetrahydrofuran (THF). The polyester resin component insoluble in tetrahydrofuran (THF) has a branched structure in the molecular skeleton while lowering Tg and melt viscosity and ensuring low-temperature fixability, and the molecular chain becomes a three-dimensional network structure. Therefore, it gives a rubber-like property that it deforms at low temperatures but does not flow.
Since the modified polyester resin has an active hydrogen group-containing compound and a site capable of reacting with the active hydrogen group-containing compound, these sites behave like pseudo-crosslinking points, and the rubber of the amorphous polyester resin It is possible to produce a toner excellent in heat-resistant storage stability and high-temperature offset resistance.

--Active hydrogen group-containing compound--
The active hydrogen group-containing compound is a compound that reacts with the polyester resin having a site capable of reacting with the active hydrogen group-containing compound.

The active hydrogen group is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), amino group, carboxyl group and mercapto group.
These may be used individually by 1 type, and may use 2 or more types together.

The active hydrogen group-containing compound is not particularly limited and can be appropriately selected depending on the intended purpose. In some cases, amines are preferred.
When the active hydrogen group-containing compound is an amine, the polyester resin can be made to have a high molecular weight by elongation reaction, cross-linking reaction, or the like with the polyester resin.

The amines are not particularly limited and can be appropriately selected depending on the intended purpose. mentioned. Among these, diamines and mixtures of diamines and a small amount of trivalent or higher amines are preferred.
These may be used individually by 1 type, and may use 2 or more types together.

The diamine is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include aromatic diamines, alicyclic diamines, and aliphatic diamines.
The aromatic diamine is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include phenylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenylmethane and the like.
The alicyclic diamine is not particularly limited and can be appropriately selected depending on the intended purpose. be done.
The aliphatic diamine is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include ethylenediamine, tetramethylenediamine, hexamethylenediamine and the like.

The trivalent or higher amine is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include diethylenetriamine and triethylenetetramine.

The aminoalcohol is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include ethanolamine and hydroxyethylaniline.

The aminomercaptan is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include aminoethylmercaptan and aminopropylmercaptan.

The amino acid is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include aminopropionic acid and aminocaproic acid.

The blocked amino group is not particularly limited and can be appropriately selected depending on the intended purpose. Examples include ketimine compounds and oxazolizone compounds.

--Polyester resin having sites capable of reacting with compounds containing active hydrogen groups--
The polyester resin having a site capable of reacting with the active hydrogen group-containing compound is not particularly limited and may be appropriately selected depending on the intended purpose. may be referred to as "polyester prepolymer containing") and the like.
The polyester resin containing the isocyanate group is not particularly limited and can be appropriately selected depending on the purpose. For example, a polyester resin having an active hydrogen group obtained by polycondensation of a polyol and a polycarboxylic acid. and a reaction product of polyisocyanate.

The polyol used for synthesizing the isocyanate group-containing polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose. A mixture with alcohol and the like are included. Among these, diols and mixtures of diols and a small amount of trihydric or higher alcohol are preferred.
These may be used individually by 1 type, and may use 2 or more types together.

The diol used in the synthesis of the isocyanate group-containing polyester resin is not particularly limited and can be appropriately selected depending on the intended purpose. formula diols, bisphenols, alkylene oxide adducts of alicyclic diols, alkylene oxide adducts of bisphenols, and the like.
Examples of the chain alkylene glycol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol and 1,6-hexanediol.
The number of carbon atoms in the chain alkylene glycol is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 2 to 12 carbon atoms.
Among these, chain alkylene glycol having 2 to 12 carbon atoms and at least one of alkylene oxide adducts of bisphenols are preferable, and alkylene oxide adducts of bisphenols, alkylene oxide adducts of bisphenols and carbon number More preferred is a mixture with a linear alkylene glycol having 2-12.
Examples of diols having an oxyalkylene group include diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.
Examples of the alicyclic diol include 1,4-cyclohexanedimethanol and hydrogenated bisphenol A.
Examples of the bisphenols include bisphenol A, bisphenol F, bisphenol S and the like.
Examples of the alkylene oxide include ethylene oxide, propylene oxide, and butylene oxide.

The trihydric or higher alcohol used in the synthesis of the polyester resin containing the isocyanate group is not particularly limited and can be appropriately selected depending on the purpose. The above polyphenols, alkylene oxide adducts of trihydric or higher polyphenols, and the like can be mentioned.
The trihydric or higher aliphatic alcohol is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and sorbitol.
The polyphenols having a valence of 3 or more are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include trisphenol PA, phenol novolak, cresol novolak and the like.
Examples of the alkylene oxide adducts of trihydric or higher polyphenols include those obtained by adding alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide to trihydric or higher polyphenols.

When the diol and the trihydric or higher alcohol are mixed and used, the mass ratio of the trihydric or higher alcohol to the diol (trihydric or higher alcohol/diol) is not particularly limited, depending on the purpose. Although it can be selected as appropriate, it is preferably 0.01% by mass to 10% by mass, more preferably 0.01% by mass to 1% by mass.

The polycarboxylic acid used for synthesizing the polyester resin containing the isocyanate group is not particularly limited and can be appropriately selected depending on the intended purpose. and a trivalent or higher carboxylic acid. Among these, dicarboxylic acids and mixtures of dicarboxylic acids and a small amount of polycarboxylic acids having a valence of 3 or more are preferred.
These may be used individually by 1 type, and may use 2 or more types together.

The dicarboxylic acid used in the synthesis of the isocyanate group-containing polyester resin is not particularly limited and can be appropriately selected depending on the purpose. group dicarboxylic acids.
The divalent alkanoic acid is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include succinic acid, adipic acid and sebacic acid.
The divalent alkenoic acid is not particularly limited and can be appropriately selected depending on the purpose, but divalent alkenoic acid having 4 to 20 carbon atoms is preferable.
The divalent alkenoic acid having 4 to 20 carbon atoms is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include maleic acid and fumaric acid.
The aromatic dicarboxylic acid is not particularly limited and can be appropriately selected depending on the purpose, but an aromatic dicarboxylic acid having 8 to 20 carbon atoms is preferable.
The aromatic dicarboxylic acid having 8 to 20 carbon atoms is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include phthalic acid, isophthalic acid, terephthalic acid and naphthalenedicarboxylic acid.

The trivalent or higher carboxylic acid used in the synthesis of the isocyanate group-containing polyester resin is not particularly limited and can be appropriately selected depending on the purpose. Examples include trivalent or higher aromatic carboxylic acids. is mentioned.
The trivalent or higher aromatic carboxylic acid is not particularly limited and may be appropriately selected depending on the purpose, but is preferably a trivalent or higher aromatic carboxylic acid having 9 to 20 carbon atoms.
The trivalent or higher aromatic carboxylic acid having 9 to 20 carbon atoms is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include trimellitic acid and pyromellitic acid.

As the polycarboxylic acid used in the synthesis of the polyester resin containing the isocyanate group, any acid anhydride of a dicarboxylic acid, a trivalent or higher carboxylic acid, or a mixture of a dicarboxylic acid and a trivalent or higher carboxylic acid Alternatively, lower alkyl esters can be used.
The lower alkyl ester is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include methyl ester, ethyl ester and isopropyl ester.

When the dicarboxylic acid and the trivalent or higher carboxylic acid are mixed and used, the mass ratio of the trivalent or higher carboxylic acid to the dicarboxylic acid (trivalent or higher carboxylic acid/dicarboxylic acid) is not particularly limited. However, it is preferably 0.01% by mass to 10% by mass, more preferably 0.01% by mass to 1% by mass.

When polycondensing the polyol and the polycarboxylic acid, the equivalent ratio of the hydroxyl group of the polyol to the carboxyl group of the polycarboxylic acid (the hydroxyl group of the polyol/the carboxyl group of the polycarboxylic acid) is not particularly limited. 1 to 2 is preferable, 1 to 1.5 is more preferable, and 1.02 to 1.3 is particularly preferable.

The content of the polyol-derived structural unit in the polyester prepolymer containing the isocyanate group is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.5% by mass to 40% by mass, 1% to 30% by mass is more preferable, and 2% to 20% by mass is particularly preferable.
When the content is 0.5% by mass or more, it is possible to solve the problem that the hot offset resistance is lowered and it is difficult to achieve both heat-resistant storage stability and low-temperature fixability of the toner. If the content is 40% by mass or less, the problem of low-temperature fixability deterioration can be resolved.

The polyisocyanate is not particularly limited and can be appropriately selected depending on the intended purpose. , oxime, caprolactam and the like.
The aliphatic diisocyanate is not particularly limited and can be appropriately selected depending on the intended purpose. diisocyanate, dodecamethylene diisocyanate, tetradecamethylene diisocyanate, trimethylhexane diisocyanate, tetramethylhexane diisocyanate and the like.
The alicyclic diisocyanate is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include isophorone diisocyanate and cyclohexylmethane diisocyanate.
The aromatic diisocyanate is not particularly limited and can be appropriately selected depending on the intended purpose. diphenyl, 4,4'-diisocyanato-3,3'-dimethyldiphenyl, 4,4'-diisocyanato-3-methyldiphenylmethane, 4,4'-diisocyanato-diphenyl ether and the like.
The araliphatic diisocyanate is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include α,α,α',α'-tetramethylxylylene diisocyanate.
The isocyanurates are not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include tris(isocyanatoalkyl)isocyanurate and tris(isocyanatocycloalkyl)isocyanurate.
These may be used individually by 1 type, and may use 2 or more types together.

When the polyisocyanate is reacted with a polyester resin having a hydroxyl group, the equivalent ratio (NCO/OH) of the isocyanate group of the polyisocyanate to the hydroxyl group of the polyester resin is not particularly limited and is appropriately selected according to the purpose. 1 to 5 are preferred, 1.2 to 4 are more preferred, and 1.5 to 2.5 are particularly preferred.
When the equivalent ratio is 1 or more, the problem of deterioration in hot offset resistance can be resolved, and when the equivalent ratio is 5 or less, the problem of deterioration in low-temperature fixability can be resolved. .

The content of the polyisocyanate-derived structural unit in the polyester prepolymer having an isocyanate group is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.5% by mass to 40% by mass, 1% by mass to 30% by mass is more preferable, and 2% by mass to 20% by mass is even more preferable.
When the content is 0.5% by mass or more, the problem of deterioration in hot offset resistance can be resolved, and when the content is 40% by mass or less, the problem of deterioration in low-temperature fixability can be solved. can be resolved.

The average number of isocyanate groups per molecule of the polyester prepolymer having an isocyanate group is not particularly limited and can be appropriately selected depending on the purpose. More preferably, 1.8 to 2.5 is even more preferable.
When the polyester prepolymer having an isocyanate group has an average number of isocyanate groups per molecule of 1 or more, the molecular weight of the modified polyester resin becomes low, which can solve the problem of deterioration in hot offset resistance. .

The modified polyester resin can be produced by a one-shot method or the like. As an example, a method for producing a urea-modified polyester resin will be described.
First, a polyol and a polycarboxylic acid are heated to 150° C. to 280° C. in the presence of a catalyst such as tetrabutoxy titanate or dibutyltin oxide, and if necessary, the water generated is removed while reducing the pressure to remove hydroxyl groups. to obtain a polyester resin having
Next, a polyester resin having hydroxyl groups and polyisocyanate are reacted at 40° C. to 140° C. to obtain a polyester prepolymer having isocyanate groups.
Furthermore, a polyester prepolymer having an isocyanate group and amines are reacted at 0° C. to 140° C. to obtain a urea-modified polyester resin.

The number average molecular weight (Mn) of the modified polyester resin is not particularly limited and can be appropriately selected depending on the purpose. , 1,500 to 6,000 are more preferred.
The weight average molecular weight (Mw) of the modified polyester resin is not particularly limited and can be appropriately selected depending on the purpose. The following are preferred.
When the weight-average molecular weight (Mw) of the modified polyester resin is 20,000 or more, the toner tends to flow at low temperatures, resulting in poor heat-resistant storage stability, and low viscosity when melted, resulting in poor high-temperature offset properties. It is possible to prevent the problem of lowering.

When reacting the polyester resin having a hydroxyl group with the polyisocyanate, and when reacting the polyester prepolymer having the isocyanate group with the amines, a solvent may be used as necessary. .

The solvent is not particularly limited and can be appropriately selected depending on the intended purpose. are mentioned.
Examples of the aromatic solvent include toluene and xylene.
Examples of the ketones include acetone, methyl ethyl ketone, and methyl isobutyl ketone.
Examples of the esters include ethyl acetate.
Examples of the amides include dimethylformamide and dimethylacetamide.
Examples of the ethers include tetrahydrofuran.

The glass transition temperature (Tg) of the modified polyester resin is preferably -60°C or higher and 0°C or lower, more preferably -40°C or higher and -20°C or lower.
If the modified polyester resin has a glass transition temperature (Tg) of −60° C. or higher, the flow of the toner at low temperatures cannot be suppressed, resulting in poor heat-resistant storage stability and poor filming resistance. can be prevented.
When the modified polyester resin has a glass transition temperature (Tg) of 0° C. or less, the toner cannot be sufficiently deformed by heat and pressure during fixing, and the problem of insufficient low-temperature fixability can be prevented. .

The content of the modified polyester resin is not particularly limited and can be appropriately selected according to the intended purpose. 10 parts by mass is more preferable.

The molecular structure of the amorphous polyester resin and the modified polyester resin can be confirmed by X-ray diffraction, GC/MS, LC/MS, IR measurement, etc., in addition to NMR measurement using a solution or solid.
Conveniently, in the infrared absorption spectrum, a method that does not have absorption based on δCH (out-of-plane bending vibration) of olefin at 965 ± 10 cm-1 and 990 ± 10 cm-1 is detected as an amorphous polyester resin. mentioned.

<<coloring agent>>
The coloring agent is not particularly limited and can be appropriately selected depending on the intended purpose. , yellow iron oxide, ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazane Yellow BGL, Isoindolinone Yellow, Bengara, Red Lead, Red Lead, Cadmium Red, Cadmium Mercury Red, Antimony Vermillion, Permanent Red 4R, Para Red , Phise Red, Parachlororthonitroaniline Red, Lithol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fastlubin B, Brilliant Scarlet G, Risol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine lake Y, alizarin lake, thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyrazolone red, polyazo red, chrome vermillion, benzidine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkali blue lake , Peacock Blue Lake, Victoria Blue Lake, Metal-Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo, Ultramarine Blue, Prussian Blue, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple , manganese purple, dioxane violet, anthraquinone violet, chromium green, zinc green, chromium oxide, pyridian, emerald green, pigment green B, naphthol green B, green gold, acid green lake, malachite glyc green lakes, phthalocyanine greens, anthraquinone greens, titanium oxide, zinc white, litbon and the like.

The content of the coloring agent is not particularly limited and can be appropriately selected according to the intended purpose. 10 parts by mass or less is more preferable.

The colorant can also be used as a masterbatch combined with a resin.
Examples of resins (masterbatch resins) that are kneaded together with the masterbatch for production of the masterbatch include, for example, polystyrene, poly-p-chlorostyrene, polyvinyltoluene, and other styrene or substituted polymers thereof; styrene-p- Chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-acrylic Butyl acid copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-methyl chloromethacrylate Copolymers, styrene-acrylonitrile copolymers, styrene-vinyl methyl ketone copolymers, styrene-butadiene copolymers, styrene-isoprene copolymers, styrene-acrylonitrile-indene copolymers, styrene-maleic acid copolymers , Styrene-based copolymers such as styrene-maleic acid ester copolymer; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, Polyvinyl butyral, polyacrylic resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax and the like.
These may be used individually by 1 type, and may use 2 or more types together.

The masterbatch can be obtained by mixing and kneading a masterbatch resin and a colorant by applying a high shearing force. At this time, an organic solvent can be used in order to enhance the interaction between the colorant and the resin. There is also a so-called flushing method, in which an aqueous paste containing water as a coloring agent is mixed and kneaded with a resin and an organic solvent, the coloring agent is transferred to the resin side, and water and the organic solvent component are removed. Since the wet cake can be used as it is, there is no need to dry it, and it is preferably used. For mixing and kneading, a high-shear dispersing device such as a three-roll mill is preferably used.

<<Wax>>
The wax (mold release agent) is not particularly limited and can be appropriately selected from known ones, and examples thereof include natural waxes and synthetic waxes.
These may be used individually by 1 type, and may use 2 or more types together.

Examples of the natural waxes include plant waxes such as carnauba wax, cotton wax, and wood wax rice wax; animal waxes such as beeswax and lanolin; mineral waxes such as ozokerite and cercin; paraffin, microcrystalline, petrolatum, and the like. and petroleum wax.
Examples of the synthetic waxes include synthetic hydrocarbon waxes such as Fischer-Tropsch wax, polyethylene and polypropylene; fatty acid amide-based compounds; low-molecular-weight crystalline polymer resins such as poly-n-stearyl methacrylate, poly-n-lauryl methacrylate, and other polyacrylate homopolymers or copolymers (e.g., n-stearyl acrylate-ethyl methacrylate copolymers, etc.); crystalline polymers having long alkyl groups in side chains;
Among these, hydrocarbon waxes such as paraffin wax, microcrystalline wax, Fischer-Tropsch wax, polyethylene wax and polypropylene wax are preferred.

The melting point of the wax is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 60° C. or higher and 80° C. or lower.
When the wax has a melting point of 60° C. or higher, the release agent is likely to melt at a low temperature, and the problem of poor heat-resistant storage stability can be prevented. When the melting point of the wax is 80° C. or less, even when the resin melts and is in the fixing temperature range, the wax does not melt sufficiently, so that fixing offset and image defects can be prevented. .

The content of the wax is not particularly limited and can be appropriately selected according to the purpose. Part by mass or less is more preferable.
When the content of the wax is 2 parts by mass or more, it is possible to prevent the problem of poor high-temperature offset resistance and low-temperature fixability during fixing, and when the content of the wax is 10 parts by mass or less. It is possible to prevent problems such as deterioration of heat-resistant storage stability and susceptibility to image fogging.

The other component (B) in the toner base particles is not particularly limited as long as it is used in ordinary toner base particles, and can be appropriately selected according to the purpose.
The content of the other component (B) is not particularly limited as long as it does not impair the properties of the toner, and can be appropriately selected according to the purpose.

<Other components (A)>
The other component (A) in the toner is not particularly limited as long as it is used in ordinary toners, and can be appropriately selected according to the purpose. property improvers, cleanability improvers, magnetic materials, and the like.

- Charge control agent -
The charge control agent is not particularly limited and can be appropriately selected depending on the intended purpose. Alkoxy-based amines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus elements or compounds, tungsten elements or compounds, fluorine-based activators, metal salicylate salts, metal salts of salicylic acid derivatives, etc. mentioned.

Examples of commercially available charge control agents include nigrosine dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, and oxynaphthoic acid metal complex E-82. , Salicylic acid-based metal complex E-84, phenolic condensate E-89 (manufactured by Orient Chemical Industry Co., Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Kogyo Co., Ltd.), LRA-901, and LR-147 which is a boron complex (manufactured by Nippon Carlit Co., Ltd.).

The content of the charge control agent is determined by the type of the binder resin, the presence or absence of additives used as necessary, and the toner manufacturing method including the dispersion method, and is univocally limited. However, it is preferably 0.1 to 10 parts by mass, more preferably 0.2 to 5 parts by mass, based on 100 parts by mass of the binder resin.
If the content of the charge control agent is 10 parts by mass or less, the chargeability of the toner is too high, reducing the effect of the main charge control agent, increasing the electrostatic attraction force with the developing roller, and increasing the developer. It is possible to solve problems such as a decrease in fluidity and a decrease in image density.
The charge control agent may be dissolved and dispersed after being melt-kneaded together with the masterbatch and the resin, or may be added directly to the organic solvent when dissolved or dispersed, or may be fixed on the toner surface after the toner particles are produced. good too.

-External Additives-
The external additive is not particularly limited and can be appropriately selected depending on the intended purpose. materials (eg, titania, alumina, tin oxide, antimony oxide, etc.), fluoropolymers, and the like. Among these, inorganic fine particles are preferable, and hydrophobic inorganic fine particles are more preferable.
The hydrophobized inorganic fine particles are not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include hydrophobized titanium oxide fine particles and hydrophobized silica fine particles.
These may be used individually by 1 type, and may use 2 or more types together.

Commercially available silica fine particles include, for example, R972, R974, RX200, RY200, R202, R805, and R812 (all manufactured by Nippon Aerosil Co., Ltd.).
Commercial products of the titania include, for example, P-25 (manufactured by Nippon Aerosil Co., Ltd.), STT-30, STT-65C-S (both manufactured by Titan Kogyo Co., Ltd.), TAF-140 (Fuji Titanium Kogyo Co., Ltd. ), MT-150W, MT-500B, MT-600B, and MT-150A (all manufactured by Tayca Corporation).
Examples of commercial products of the hydrophobized titanium oxide fine particles include T-805 (manufactured by Nippon Aerosil Co., Ltd.), STT-30A, STT-65S-S (all manufactured by Titan Kogyo Co., Ltd.), TAF- 500T, TAF-1500T (both manufactured by Fuji Titanium Industry Co., Ltd.), MT-100S, MT-100T (both manufactured by Tayca Corporation), IT-S (manufactured by Ishihara Sangyo Co., Ltd.), and the like.

The hydrophobization treatment can be performed, for example, on hydrophilic fine particles using a silane coupling agent such as methyltrimethoxysilane, methyltriethoxysilane, octyltrimethoxysilane, or the like.
In addition, silicone oil-treated oxide microparticles and silicone oil-treated inorganic microparticles obtained by treating silicone oil into inorganic microparticles or oxide microparticles are also suitable. In the treatment using the silicone oil, heat may be applied as necessary.

The silicone oil is not particularly limited and can be appropriately selected depending on the intended purpose. Modified silicone oil, polyether-modified silicone oil, alcohol-modified silicone oil, amino-modified silicone oil, epoxy-modified silicone oil, epoxy/polyether-modified silicone oil, phenol-modified silicone oil, carboxyl-modified silicone oil, mercapto-modified silicone oil, methacryl-modified silicone oil Examples include silicone oil and α-methylstyrene-modified silicone oil.

The average particle diameter of the primary particles in the external additive is not particularly limited, and can be appropriately selected according to the purpose. 5 nm to 70 nm is particularly preferred.
When the average particle size of the primary particles in the external additive is within the above range, the inorganic fine particles are buried in the toner, making it difficult to effectively exhibit their functions, and the problem is that the surface of the photoreceptor is unevenly damaged. can be prevented.
The external additive preferably contains at least one type of inorganic fine particles having an average particle size of 20 nm or less and at least one type of inorganic fine particles having an average particle size of 30 nm or more.
The specific surface area of the external additive according to the BET method is preferably 20 m ² /g to 500 m ² /g.

The content of the external additive is not particularly limited and can be appropriately selected according to the purpose. .3 mass parts or more and 3 mass parts or less are more preferable.

- Fluidity improver -
The fluidity improver is not particularly limited as long as it can be subjected to surface treatment to increase hydrophobicity and prevent deterioration of fluidity and charging characteristics even under high humidity, and can be appropriately selected according to the purpose. Examples include silane coupling agents, silylating agents, silane coupling agents having alkyl fluoride groups, organic titanate-based coupling agents, aluminum-based coupling agents, silicone oils, and modified silicone oils. be done.
It is particularly preferable that the silica and titanium oxide are surface-treated with the fluidity improver and used as hydrophobic silica and hydrophobic titanium oxide.

- Cleanability improver -
The cleaning improver is not particularly limited as long as it is added to the toner in order to remove the developer remaining on the photoreceptor or the primary transfer medium after transfer, and may be appropriately selected according to the purpose. Examples thereof include zinc stearate, calcium stearate, fatty acid metal salts such as stearic acid, polymethyl methacrylate fine particles, polystyrene fine particles and the like produced by soap-free emulsion polymerization.
As the polymer fine particles, those having a relatively narrow particle size distribution are preferable, and those having a volume average particle diameter of 0.01 μm to 1 μm are also preferable.

－Magnetic materials－
The magnetic material is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include iron powder, magnetite, and ferrite. Among these, white ones are preferable in terms of color tone.

In the toner of the present invention, the glass transition temperature (Tg1st) in the first temperature rise in differential scanning calorimetry (DSC) is preferably 40°C to 65°C.
In the tetrahydrofuran (THF)-insoluble component of the toner, the glass transition temperature (Tg1st) in the first DSC temperature rise is preferably -45°C to 5°C.
The THF-soluble component of the toner preferably has a glass transition temperature (Tg2nd) of 20° C. to 65° C. in the second temperature rise of DSC.
The glass transition temperature (Tg1st) at the first temperature rise and the glass transition temperature (Tg2nd) at the second temperature rise in differential scanning calorimetry (DSC) of the toner were determined to be a toner with improved low-temperature fixability and heat-resistant storage stability. It is preferable to satisfy Tg1st−Tg2nd≧10 [° C.] in that it can be obtained.

The glass transition temperature of the toner can be measured using, for example, a differential scanning calorimeter (DSC-60, manufactured by Shimadzu Corporation).
For example, a DSC curve is measured using the differential scanning calorimeter. From the obtained DSC curve, an analysis program is used to select the DSC curve at the time of the first heating, and the endothermic shoulder temperature in the analysis program is used to obtain the glass transition temperature (Tg1st) at the first heating. be able to. The glass transition temperature (Tg2nd) at the second temperature increase can be obtained by selecting the DSC curve at the time of the second temperature increase and using the endothermic shoulder temperature.

<Aggregate of fine resin particles>
In the present invention, the resin fine particles (B) and aggregates formed by aggregation of the resin fine particles (B) are present on the surface of the toner base particles.
The term "aggregates" in the present invention means particles having a major diameter of 3R or more, where R is the major diameter of the smallest particle in the fine resin particles (B) present on the surface of the toner base particles.
The term "minimum particle" in the present invention indicates a resin particle having the smallest outer periphery among resin particles (resin fine particles or aggregates) present on the toner base particles.
It should be noted that the length of the aggregate in the present invention is defined as R'.

<Method for measuring major diameters R and R'>
The external additive is removed from the toner as much as possible by subjecting the toner to a release treatment of the external additive using ultrasonic waves, and after the toner is brought into a state close to that of the toner base particles, the major axis R of the smallest particle is determined.
[1] 50 ml of a 5 mass % aqueous solution containing a surfactant (trade name: Neugen ET-165, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added to a 100 ml screw tube, and 3 g of toner was added to the mixture. Gently move up, down, left and right. After that, the dispersion solution is agitated for 30 minutes by a ball mill so that the toner is blended with the dispersion solution.
[2] Using an ultrasonic homogenizer (trade name: homogenizer, model VCX750, CV33, manufactured by SONICS & MATERIALS Co., Ltd.), set the output to 40 W and apply ultrasonic energy for 60 minutes.
-Ultrasonic conditions-
・Vibration time: 60 minutes continuous ・Amplitude: 40W
・Vibration start temperature: 23±1.5℃
・Temperature during vibration: 23±1.5℃
[3] (1) The dispersion liquid is suction-filtered through a filter paper (trade name: qualitative filter paper (No. 2, 110 mm), manufactured by Advantec Toyo Co., Ltd.), washed twice with deionized water, and then filtered again. After removing the free additive, the toner is dried.
(2) The toner obtained in (1) is randomly selected and observed with a scanning electron microscope (SEM). First, an external additive or charge control agent containing Si is detected by observing a backscattered electron image, and the backscattered electron image is taken.
(3) The obtained backscattered electron image is subjected to binarization processing (threshold value: 135) using image processing software (ImageJ) to produce an image from which the external additive and the charge control agent are eliminated.
(4) Observe and take a secondary electron image at the same position as (2). Since the fine resin particles (OMS) are not observed in the backscattered electron image but are observed only in the secondary electron image, the image obtained in (3) is compared with the image obtained in (3), and the portion other than the residual external additive and the charge control agent (( Particles present in the portion other than those excluded in 3) are defined as resin particles (resin fine particles or aggregates).
(5) Image processing software (ImageJ) is used to measure the circumference of the resin particles (resin fine particles or aggregates) on the toner base particles, and the resin particles with the smallest circumference are taken as the smallest particles. Note that the smallest particle is determined in units of one toner particle, not in units of one visual field.
(6) Let the major axis R be the diameter of a perfect circle having the same circumference as the measured outer circumference of the smallest particle.
Regarding the long axis R' of the aggregate, the outer circumference is measured in the same manner as the long axis R, and the diameter of a perfect circle having the same circumference as the outer circumference obtained by the measurement is defined as the long axis R'.

<Aggregate occupancy>
In the present invention, the proportion of the surface of the toner base particles occupied by the aggregates is 15% or more and 60% or less.
In addition, in the present invention, the "proportion of the surface of the toner base particles occupied by the aggregates" may be referred to as "occupancy".

The occupation rate is preferably 15% or more and 60% or less, more preferably 15% or more and 35% or less.
When the occupancy is 15% or more and 60% or less, it is possible to optimize the liberation amount of the external additive, suppress the occurrence of filming, and achieve excellent cleaning performance due to low-temperature fixability and low adhesion. can be achieved at a high level.
When the occupancy is 15% or more, the external additive on the surface of the toner base particles is easily liberated, and the problem that filming is likely to occur due to excessive liberation can be solved.
When the occupancy is 60% or less, it is possible to solve the problem that the agglomerates hinder the transmission of heat from the fixing roller and sufficient low-temperature fixability cannot be obtained.

<Standard deviation in distance between resin fine particles>
In the present invention, the distance between the resin fine particles indicates the shortest distance between the resin fine particle surface existing on the surface of the toner base particle and the adjacent resin fine particle surface not in contact with the resin fine particle.
In the present invention, "the shortest distance between the resin fine particle surface existing on the surface of the toner base particle and the adjacent resin fine particle surface that is not in contact with the resin fine particle" is referred to as "the distance between the resin fine particles". Sometimes.
Since the surface of the toner base particles is not flat but slightly rounded (curved), the distance between the resin microparticles is not the distance between the resin microparticles on the surface of the toner base particles. It is the shortest distance between the fine resin particles on the image of the fine resin particles on the surface of the toner base particles taken by a scanning electron microscope (SEM).

In the toner of the present invention, the standard deviation of the distance between adjacent resin fine particles that are not in contact with each other on the surface of the toner base particles is preferably 500 nm or less, more preferably 300 nm or less. , 150 nm or less.
When the standard deviation of the distance between the resin fine particles is 500 nm or less, the protective action expected of the resin fine particles on the surface of the toner base particles is not locally exhibited, thereby solving the problem of deterioration of reliability. can be done.

<Method for measuring occupancy rate and distance between fine resin particles>
The external additive is removed from the toner as much as possible by subjecting the toner to liberation treatment of the external additive using ultrasonic waves, and after the toner is brought into a state similar to that of the toner base particles, the occupancy rate and the distance between the fine resin particles are obtained.
[1] 50 ml of a 5 mass % aqueous solution containing a surfactant (trade name: Neugen ET-165, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added to a 100 ml screw tube, and 3 g of toner was added to the mixture. Gently move up, down, left and right. After that, the dispersion solution is agitated for 30 minutes by a ball mill so that the toner is blended with the dispersion solution.
[2] Using an ultrasonic homogenizer (trade name: homogenizer, model VCX750, CV33, manufactured by SONICS & MATERIALS Co., Ltd.), set the output to 40 W and apply ultrasonic energy for 60 minutes.
-Ultrasonic conditions-
・Vibration time: 60 minutes continuous ・Amplitude: 40W
・Vibration start temperature: 23±1.5℃
・Temperature during vibration: 23±1.5℃
[3] (1) The dispersion liquid is suction-filtered through a filter paper (trade name: qualitative filter paper (No. 2, 110 mm), manufactured by Advantec Toyo Co., Ltd.), washed twice with deionized water, and then filtered again. After removing the free additive, the toner is dried.
(2) The toner obtained in (1) is randomly selected and observed with a scanning electron microscope (SEM). First, an external additive or charge control agent containing Si is detected by observing a backscattered electron image, and the backscattered electron image is captured.
(3) The obtained backscattered electron image is subjected to binarization processing (threshold value: 135) using image processing software (ImageJ) to produce an image from which the external additive and the charge control agent are eliminated.
(4) Observe and take a secondary electron image at the same position as (2). Since the fine resin particles (OMS) are not observed in the backscattered electron image, but are observed only in the secondary electron image, the image obtained in (3) is compared with the image obtained in (3), and the portion other than the residual external additive and the charge control agent (( Particles present in the portion other than those excluded in 3) are defined as resin particles (resin fine particles or aggregates). Note that the locations where the toner particles are photographed are randomly selected.
(5) Using image processing software (ImageJ), binarization processing (threshold: 135) is performed to produce 100 binarized images (one toner particle per image). From the obtained binary image, the total area occupied by each aggregate, the area of the toner base particles, and the distance between the fine resin particles are measured.
(6) For the total area occupied by each aggregate and the area of the toner base particles, an average value is obtained to calculate the occupation rate. A standard deviation is calculated for the distance between the resin fine particles.
The total area occupied by each aggregate and the area of the toner base particles are defined as the area of a perfect circle having the same circumference as the outer circumference obtained by measurement, and the area of each of the aggregates and the toner base particles. and

The occupation rate is calculated by the following formula.
Occupancy rate (%) = average value of total area occupied by aggregates/average value of area of toner base

The standard deviation of the distance between the resin fine particles is calculated by the following formula, where x is the distance between the particles.

The imaging conditions for the scanning electron microscope (SEM) are shown below.
[Shooting conditions]
・ Scanning electron microscope: SU-8230 (manufactured by Hitachi High-Technologies Corporation)
・Photographing magnification: 60000 times ・Photographed image: SE (L): secondary electrons, BSE (backscattered electrons)
・Acceleration voltage: 3.0 kV
・Acceleration current: 1.0 μA
・Probe current: Normal
・Focus mode: UHR
・WD: 8.0mm

Here, the toner according to the present invention will be described with reference to the drawings. In addition, the present invention is not limited to the embodiments shown below, and can be changed within the scope of those skilled in the art, such as other embodiments, additions, modifications, deletions, etc. is also included in the scope of the present invention as long as the functions and effects of the present invention are exhibited.

FIG. 1 is a schematic diagram showing an example of the state of the toner surface. Resin fine particles 3 and aggregates 5 composed of resin fine particles are present on the surface of the toner base particles 4 . The resin fine particles 3 consist of a core resin 2 and a shell resin 1 . M indicates the volume average primary particle size of the resin fine particles 3 . L indicates the distance between resin fine particles.

(developer)
The developer of the present invention contains at least the toner of the present invention and, if necessary, other components such as a carrier that are appropriately selected. The developer may be either a one-component developer or a two-component developer. However, when used in high-speed printers that are compatible with the recent improvement in information processing speed, the life of the developer is expected to be extended. Therefore, a two-component developer is preferred.

<Carrier>
The carrier is not particularly limited and can be appropriately selected depending on the intended purpose, but preferably has a core material and a resin layer covering the core material.

<< core material >>
The material of the core material is not particularly limited and can be appropriately selected according to the purpose. Examples include magnesium-based materials. Further, in order to ensure image density, it is preferable to use a highly magnetized material such as iron powder of 100 emu/g or more and magnetite of 75 emu/g to 120 emu/g. In addition, a low magnetization material such as a copper-zinc system with a concentration of 30 emu/g to 80 emu/g can be used because it is possible to reduce the impact of the standing developer on the photoreceptor, which is advantageous for achieving high image quality. is preferred.
These may be used individually by 1 type, and may use 2 or more types together.

The volume-average particle size of the core material is not particularly limited and can be appropriately selected depending on the intended purpose.
When the volume average particle size of the core material is 10 μm or more, the problem of scattering of the carrier due to a decrease in magnetization per particle due to a large amount of fine powder in the carrier can be resolved.
If the volume average particle size of the core material is 150 μm or less, the specific surface area is reduced, causing scattering of the toner, thereby solving the problem that the reproduction of solid portions is particularly poor in full-color images with many solid portions. can be done.

The toner of the present invention can be mixed with the carrier and used in a two-component developer.
The content of the carrier in the two-component developer is not particularly limited and can be appropriately selected according to the purpose. The following is preferable, and 93 parts by mass or more and 97 parts by mass or less is more preferable.
The developer of the present invention can be suitably used for image formation by various known electrophotographic methods such as a magnetic one-component development method, a non-magnetic one-component development method, and a two-component development method.

(Toner manufacturing method)
A method for producing a toner according to the present invention is a method for producing the toner.
The method for producing the toner includes a composite particle forming step, a removing step, and, if necessary, other steps.

<Composite Particle Forming Step>
The composite particle forming step is a step of adhering the fine resin particles to the surface of the toner base particles to form composite particles.
The method for forming the composite particles is not particularly limited and can be appropriately selected according to the purpose. A known dissolution suspension method of granulating by dispersing in a medium, and the like can be mentioned.

As an example of the dissolution and suspension method, a method of forming composite particles while generating a polyester resin through an elongation reaction and/or a cross-linking reaction between the prepolymer and a curing agent will be described.
In this method, an aqueous medium (aqueous phase) is prepared, an oil phase containing toner base particle materials is prepared, the toner base particle materials are emulsified or dispersed, and an organic solvent is removed.

-Preparation of aqueous medium (aqueous phase)-
The aqueous medium can be prepared, for example, by dispersing fine resin particles in the aqueous medium.
The amount of the fine resin particles to be added to the aqueous medium is not particularly limited and can be appropriately selected according to the intended purpose.

The aqueous medium is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include water, water-miscible solvents, and mixtures thereof. Among these, water is preferred. These may be used individually by 1 type, and may use 2 or more types together.
The water-miscible solvent is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include alcohols, dimethylformamide, tetrahydrofuran, cellosolves, lower ketones and the like.
Examples of the alcohol include methanol, isopropanol, ethylene glycol, and the like.
Examples of the lower ketones include acetone and methyl ethyl ketone.

-Preparation of oil phase-
The oil phase is prepared by dissolving or dispersing in an organic solvent a toner base particle material containing a binder resin, a colorant, a wax, and, if necessary, a curing agent and the like. can be done.
The curing agent is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include isophoronediamine (IPDA).

The organic solvent is not particularly limited and can be appropriately selected depending on the intended purpose, but an organic solvent having a boiling point of less than 150° C. is preferable because it is easy to remove.
Examples of organic solvents having a boiling point of less than 150° C. include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, and dichloroethylidene. , methyl acetate, ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone and the like. Among these, ethyl acetate, toluene, xylene, benzene, methylene chloride, 1,2-dichloroethane, chloroform, carbon tetrachloride and the like are preferred, and ethyl acetate is more preferred.
These may be used individually by 1 type, and may use 2 or more types together.

-Emulsification or dispersion-
The emulsification or dispersion of the material of the toner can be carried out by dispersing the oil phase containing the material of the toner base particles in the aqueous medium. When emulsifying or dispersing the material of the toner, the curing agent and the prepolymer can undergo extension reaction and/or cross-linking reaction.

The reaction conditions (reaction time, reaction temperature) for forming the prepolymer are not particularly limited, and can be appropriately selected according to the combination of the curing agent and the prepolymer.
The reaction time is preferably 10 minutes to 40 hours, more preferably 2 to 24 hours.
The reaction temperature is preferably 0°C to 150°C, more preferably 40°C to 98°C.

The method for stably forming the dispersion containing the prepolymer in the aqueous medium is not particularly limited and can be appropriately selected according to the purpose. A method of adding an oil phase prepared by dissolving or dispersing it in a solvent and dispersing it by shearing force can be used.

The disperser for the dispersion is not particularly limited and can be appropriately selected according to the purpose. , an ultrasonic disperser, and the like. Among these, a high-speed shear type disperser is preferable in that the particle size of the dispersion (oil droplets) can be controlled to 2 μm to 20 μm.

When the high-speed shear type disperser is used, the conditions such as rotation speed, dispersion time, and dispersion temperature can be appropriately selected according to the purpose.
The rotational speed is preferably 1,000 rpm to 30,000 rpm, more preferably 5,000 rpm to 20,000 rpm.
The dispersion time is preferably 0.1 to 5 minutes in the case of a batch system.
The dispersion temperature is preferably 0° C. to 150° C., more preferably 40° C. to 98° C. under pressure. In general, the higher the dispersion temperature, the easier the dispersion.

The amount of the aqueous medium used when emulsifying or dispersing the toner material is not particularly limited and can be appropriately selected according to the purpose. ,000 parts by mass, and more preferably 100 to 1,000 parts by mass.
When the amount of the aqueous medium used is 50 parts by mass or more, it is possible to solve the problem that the dispersion state of the toner material deteriorates and toner base particles having a predetermined particle size cannot be obtained. When the amount of the aqueous medium used is 2,000 parts by mass or less, it is possible to solve the problem of high production costs.

When emulsifying or dispersing the oil phase containing the toner material, it is preferable to use a dispersant from the viewpoint of stabilizing the dispersion such as oil droplets, forming a desired shape, and sharpening the particle size distribution.
The dispersant is not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include surfactants, poorly water-soluble inorganic compound dispersants, polymeric protective colloids, and the like. Among these, surfactants are preferred.
These may be used individually by 1 type, and may use 2 or more types together.

The surfactant used as the dispersant is not particularly limited and can be appropriately selected depending on the purpose. A surfactant or the like can be used.
Examples of the anionic surfactant used as the dispersant include alkylbenzenesulfonates, α-olefinsulfonates, and phosphate esters. Among these, those having a fluoroalkyl group are preferred.

-Removal of organic solvent-
The method for removing the organic solvent from the dispersion such as the emulsified slurry is not particularly limited and can be appropriately selected according to the purpose. Examples include a method of evaporating the solvent, a method of spraying the dispersion into a dry atmosphere to remove the organic solvent in the oil droplets, and the like.
Composite particles are formed when the organic solvent is removed.

<Removal process>
The removing step is a step of removing at least part of the fine resin particles from the composite particles, and preferably part or all of the shell resin (resin (b1)) in the fine resin particles is removed.
The step of removing at least part of the fine resin particles includes, for example, a washing step of washing the composite particles. For this reason, the removal process can also be said to be a cleaning process.

In the washing step, examples of the method for removing part or all of the resin (b1) include a method of removing part or all of the resin (b1) by a chemical method.
The chemical method is not particularly limited and can be appropriately selected according to the purpose. Examples thereof include a step of washing the composite particles using a basic aqueous solution. Part or all of the shell resin (b1) can be dissolved by washing the composite particles with a basic aqueous solution.

The basic aqueous solution is not particularly limited as long as it is basic, and can be appropriately selected according to the purpose. For example, aqueous solutions of alkali metal hydroxides such as potassium hydroxide and sodium hydroxide , and ammonia. Among these, potassium hydroxide and sodium hydroxide are preferable from the viewpoint of easily dissolving the shell resin (b1).
These may be used individually by 1 type, and may use 2 or more types together.
The pH of the basic aqueous solution is preferably 8-14, more preferably 10-12.

Mixing of the composite particles and the basic aqueous solution in the washing step can be performed by a method such as dropping the basic aqueous solution into the composite slurry while stirring.
After the basic aqueous solution is added dropwise, the acid aqueous solution may be added dropwise for neutralization.

<Other processes>
The other steps are not particularly limited and can be appropriately selected depending on the intended purpose. Examples thereof include a drying step and a classification step.
The drying step is not particularly limited as long as the solvent can be removed from the composite particles, and can be appropriately selected depending on the purpose.
The classification step is not particularly limited and can be appropriately selected according to the purpose. For example, it may be carried out by removing the fine particle portion in a liquid by a cyclone, decanter, centrifugal separation, etc., or a classification operation may be performed after drying. you can go

The composite particles obtained by the composite particle formation step, the removal step, and the other steps may be mixed with particles such as the external additive and the charge control agent. At this time, by applying a mechanical impact force, it is possible to suppress detachment of the particles such as the external additive from the surface of the toner base particles.
The method for applying the mechanical impact force is not particularly limited and can be appropriately selected according to the purpose. The mixture is put into the chamber and accelerated to collide the particles with each other or against a suitable collision plate.

The device used in the method of applying the mechanical impact force is not particularly limited and can be appropriately selected according to the purpose. (manufactured by Nara Machinery Co., Ltd.), a hybridization system (manufactured by Nara Machinery Co., Ltd.), a cryptoron system (manufactured by Kawasaki Heavy Industries, Ltd.), an automatic mortar, and the like.

(toner storage unit)
The toner containing unit in the present invention indicates a unit having a function of containing toner and containing the toner of the present invention. Here, examples of the toner storage unit include a toner storage container, a developing device, a process cartridge, and the like.
The toner container means a container containing the toner of the present invention.
The developing device has means for accommodating and developing the toner of the present invention.
The process cartridge refers to a cartridge that integrates at least an image carrier and developing means, stores the toner of the present invention, and is detachable from the image forming apparatus. The process cartridge may further comprise at least one selected from charging means, exposure means and cleaning means.

Here, a process cartridge according to the present invention will be described with reference to the drawings. In addition, the present invention is not limited to the embodiments shown below, and can be changed within the scope of those skilled in the art, such as other embodiments, additions, modifications, deletions, etc. is also included in the scope of the present invention as long as the functions and effects of the present invention are exhibited.

One embodiment of the process cartridge is shown in FIG. As shown in FIG. 2, the process cartridge of this embodiment contains a latent image carrier 101, a charging device 102, a developing device 104, a cleaning section 107, and, if necessary, other means. In FIG. 2, reference numeral 103 denotes exposure from an exposure device, and reference numeral 105 denotes recording paper.
As the latent image carrier 101, the same electrostatic latent image carrier in an image forming apparatus, which will be described later, can be used. Any charging member is used for the charging device 102 .
In the image forming process by the process cartridge shown in FIG. 2, the latent image carrier 101 is charged by a charging device 102 while rotating clockwise in FIG. An electrostatic latent image is formed on the surface corresponding to the exposed image.
The electrostatic latent image is toner-developed by the developing device 104, and the toner-developed image is transferred to the recording paper 105 by the transfer roller 108 and printed out. After the image transfer, the surface of the latent image bearing member is cleaned by the cleaning unit 107, and then neutralized by a neutralizing means (not shown), and the above operations are repeated.

(Image forming apparatus and image forming method)
The image forming apparatus of the present invention has the toner storage unit described above, and has at least an electrostatic latent image carrier, an electrostatic latent image forming means, and a developing means, and further, if necessary, other means. It is preferred to have
The image forming method of the present invention includes at least an electrostatic latent image forming step and a developing step, and further includes other steps as necessary.

<Electrostatic latent image carrier>
The material, structure, and size of the electrostatic latent image carrier are not particularly limited, and can be appropriately selected from known ones.
Examples of the material of the electrostatic latent image carrier include inorganic photoreceptors such as amorphous silicon and selenium, and organic photoreceptors such as polysilane and phthalopolymethine. Among these, amorphous silicon is preferable in terms of long life.
The linear velocity of the electrostatic latent image carrier is preferably 300 mm/s or more.

<Electrostatic latent image forming means and electrostatic latent image forming step>
The electrostatic latent image forming means is not particularly limited as long as it is means for forming an electrostatic latent image on the electrostatic latent image carrier, and can be appropriately selected according to the purpose. Examples include means having at least a charging member for charging the surface of the electrostatic latent image carrier and an exposure member for imagewise exposing the surface of the electrostatic latent image carrier.
The electrostatic latent image forming step is not particularly limited as long as it is a step of forming an electrostatic latent image on the electrostatic latent image carrier, and can be appropriately selected according to the purpose. After the surface of the electrostatic latent image carrier is charged, it can be exposed imagewise, and can be carried out using the electrostatic latent image forming means.

- Charging member and charging -
The charging member is not particularly limited and can be appropriately selected according to the intended purpose. , corotron, scorotron, and other non-contact chargers using corona discharge. Among these, it is preferable to use a contact-type charging member in that an image forming apparatus in which ozone generated from the charging member is reduced can be obtained.
The shape of the charging member may be a roller, a magnetic brush, a fur brush, or any other shape, and can be selected according to the specifications and shape of the image forming apparatus.

The charging can be performed, for example, by applying a voltage to the surface of the electrostatic latent image carrier using the charging member.

<<Exposure member and exposure>>
The exposure member is not particularly limited as long as the surface of the electrostatic latent image carrier charged by the charging member can be exposed in an image-wise manner to be formed, and is appropriately selected according to the purpose. Examples include various exposure members such as copying optical systems, rod lens array systems, laser optical systems, and liquid crystal shutter optical systems.

The light source used for the exposure member is not particularly limited and can be appropriately selected depending on the intended purpose. (LD) and electroluminescence (EL).
Further, the light source used for the exposure member includes a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, a color temperature conversion filter, etc., in order to irradiate light only in a desired wavelength range. can also be used.

The exposure can be performed, for example, by imagewise exposing the surface of the electrostatic latent image carrier using the exposure member.
In addition, in the present invention, a light rear surface method in which imagewise exposure is performed from the rear surface side of the electrostatic latent image carrier may be employed.

<Developing means and developing process>
The developing means is not particularly limited as long as it has toner for developing the electrostatic latent image formed on the electrostatic latent image bearing member to form a visible toner image. It can be appropriately selected depending on the purpose.
The developing step is particularly limited as long as it is a step of forming a visible toner image by developing the electrostatic latent image formed on the electrostatic latent image carrier with toner. However, it can be appropriately selected depending on the purpose, and for example, it can be carried out by the developing means.
The developing means includes a stirrer for charging the toner by frictionally stirring it, and a magnetic field generating means fixed inside, and a rotatable developer carrying developer containing the toner on its surface. A developing device having a body is preferred.

<Other means and other steps>
Examples of the other means include transfer means, fixing means, cleaning means, charge removing means, and recycling means.
Examples of the other processes include a transfer process, a fixing process, a cleaning process, a static elimination process, and a recycling process.

-Transfer Means and Transfer Process-
The transfer means is not particularly limited as long as it is a means for transferring a visible image to a recording medium, and can be appropriately selected according to the purpose. It is preferable to have a primary transfer means for forming a transfer image and a secondary transfer means for transferring the composite transfer image onto a recording medium.
The transfer step is not particularly limited as long as it is a step of transferring a visible image onto a recording medium, and can be appropriately selected according to the purpose. It is preferable that the visual image is primarily transferred and then the visible image is secondarily transferred onto the recording medium.
The transfer step can be performed, for example, by charging the visible image to the photoreceptor using a transfer charger, and can be performed by the transfer means.

Here, when the image to be secondarily transferred onto the recording medium is a color image made of toner of a plurality of colors, the transfer means sequentially superimposes the toners of each color on the intermediate transfer body to form the intermediate image. An image may be formed on a transfer member, and the image on the intermediate transfer member may be secondarily transferred onto the recording medium by the intermediate transfer means.
The intermediate transfer member is not particularly limited, and can be appropriately selected from known transfer members depending on the purpose. Examples of the intermediate transfer member include transfer belts.

It is preferable that the transfer means (the primary transfer means and the secondary transfer means) have at least a transfer device that separates and charges the visible image formed on the photoreceptor toward the recording medium. .
Examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, an adhesive transfer device, and the like.
The recording medium is typically plain paper, but is not particularly limited as long as it can transfer an unfixed image after development, and can be appropriately selected according to the purpose. A PET base or the like can also be used.

- Fixing means and fixing process -
The fixing means is not particularly limited as long as it is means for fixing the transferred image transferred to the recording medium, and can be appropriately selected according to the purpose. For example, a known heating and pressurizing member is preferable.
Examples of the heating and pressing member include a combination of a heating roller and a pressure roller, and a combination of a heating roller, a pressure roller and an endless belt.
The fixing step is not particularly limited as long as it is a step of fixing the visible image transferred to the recording medium, and can be appropriately selected according to the purpose. It may be carried out each time the toner is transferred to the toner of each color, or may be carried out simultaneously in a state where the toner of each color is laminated. The fixing step can be performed by the fixing means.
The heating in the heating and pressurizing member is preferably 80.degree. C. to 200.degree.

In the present invention, depending on the purpose, for example, a known optical fixing device may be used together with or in place of the fixing means.
The surface pressure in the fixing step is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 10 N/cm ² to 80 N/cm ² .

<<Cleaning means and cleaning process>>
The cleaning means is not particularly limited as long as it can remove the toner remaining on the photoreceptor, and can be appropriately selected according to the purpose. Magnetic roller cleaners, blade cleaners, brush cleaners, web cleaners, and the like.
The cleaning step is not particularly limited as long as it can remove the toner remaining on the photoreceptor, and can be appropriately selected according to the purpose. For example, the cleaning means can be used.

- Static Eliminating Means and Static Eliminating Step -
The charge removing means is not particularly limited as long as it removes charges by applying a charge removing bias to the photoreceptor, and can be appropriately selected according to the purpose. Examples thereof include a charge removing lamp.
The static elimination process is not particularly limited as long as it is a process of applying a static elimination bias to the photosensitive member to eliminate static electricity, and can be appropriately selected according to the purpose. .

- Recycling means and recycling process -
The recycling means is not particularly limited as long as it is a means for recycling the toner removed in the cleaning process to the developing device, and can be appropriately selected according to the purpose. mentioned.
The recycling step is not particularly limited as long as it is a step of recycling the toner removed in the cleaning step to the developing device, and can be appropriately selected according to the purpose. can be done.

Here, an image forming apparatus according to the present invention will be described with reference to the drawings. In addition, the present invention is not limited to the embodiments shown below, and can be changed within the scope of those skilled in the art, such as other embodiments, additions, modifications, deletions, etc. is also included in the scope of the present invention as long as the functions and effects of the present invention are exhibited.

One aspect of implementing the method of forming an image by the image forming apparatus of the present invention will be described with reference to FIG. Note that although a printer is shown as an example of the image forming apparatus of the present embodiment, the image forming apparatus of the present invention can form an image using toner of a copying machine, a facsimile machine, a multifunction machine, or the like. If there is, it is not particularly limited.
The image forming apparatus includes a paper feeding section 210 , a conveying section 220 , an image forming section 230 , a transfer section 240 and a fixing device 250 .
The paper feed unit 210 includes a paper feed cassette 211 on which paper P to be fed is stacked and a paper feed roller 212 that feeds the paper P stacked in the paper feed cassette 211 one by one.

The transport unit 220 stands by with a roller 221 that transports the paper P fed by the paper feed roller 212 toward the transfer unit 240 and the leading end of the paper P transported by the roller 221, and holds the paper in a predetermined direction. It has a pair of timing rollers 222 that send out to the transfer section 240 at the timing, and a paper discharge roller 223 that discharges the paper P on which the color toner image is fixed to the paper discharge tray 224 .

The image forming unit 230 has an image forming unit 180Y that forms an image using a developer containing yellow toner and a cyan toner in order from left to right in the figure at a predetermined interval. An image forming unit 180C using a developer containing magenta toner, an image forming unit 180M using a developer containing magenta toner, an image forming unit 180K using a developer containing black toner, and an exposure device 233 are provided.
The image forming unit image forming unit 180 (180Y, 180C, 180M, 180K) is provided rotatably clockwise in the drawing, and the photosensitive drum 231 (231Y) on which an electrostatic latent image and a toner image are formed. , 231C, 231M, 231K), chargers 232 (232Y, 232C, 232M, 232K) that uniformly charge the surfaces of the photosensitive drums 231 (231Y, 231C, 231M, 231K), and the photosensitive drums 231 (231Y , 231C, 231M, and 231K) are provided.
Further, the image forming units 180 (180Y, 180C, 180M, 180K) include toner bottles 234 (234Y, 234C, 234M, 234K) containing toners of respective colors, and toner bottles 234 (234Y, 234C, 234M, 234K). It has sub-hoppers 160 (160Y, 160C, 160M, 160K) for replenishing supplied toner.
An arbitrary image forming unit among the image forming units 180 (180Y, 180C, 180M, 180K) is referred to as an image forming unit.

The exposure device 233 reflects a laser beam L emitted from a light source 233a based on image information by a polygon mirror 233b (233bY, 233bC, 233bM, 233bK) rotated by a motor, and irradiates the photosensitive drum 231 with the laser beam L. .
Also, the developer has toner and carrier. The four image forming units 180 (180Y, 180C, 180M, and 180K) have substantially the same mechanical configuration, with the only difference being the developer used.

The transfer unit 240 includes a drive roller 241 and a driven roller 242, an intermediate transfer belt 243 that can rotate counterclockwise in FIG. Primary transfer rollers 244 (244Y, 244C, 244M, 244K) provided facing body drums 231 (231Y, 231C, 231M, 231K) and intermediate transfer belt 243 at the transfer position of the toner image onto paper. A secondary opposing roller 245 and a secondary transfer roller 246 are provided facing each other.

The fixing device 250 is provided with a heater inside, and includes a pressure roller 252 that forms a nip by rotatably pressing a fixing belt 251 that heats the paper P against the fixing belt 251 . . As a result, heat and pressure are applied to the color toner image on the paper P to fix the color toner image. The paper P on which the color toner image is fixed is discharged to the paper discharge tray 224 by the paper discharge rollers 223, and a series of image forming processes is completed.

Examples of the present invention will be described below, but the present invention is not limited to these examples.

(Production example 1)
<Synthesis of amorphous polyester (low molecular weight polyester) resin>
A 5-liter four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was charged with the following materials and reacted at 230° C. for 7 hours under normal pressure.
-material-
・Bisphenol A ethylene oxide 2 mol adduct 229 parts by mass ・Bisphenol A propylene oxide 2 mol adduct 529 parts by mass ・Terephthalic acid 208 parts by mass ・Adipic acid 46 parts by mass ・Dibutyltin oxide 2 parts by mass After reacting for 4 hours under low temperature, 44 parts by mass of trimellitic anhydride was added to the reaction vessel and reacted at 180° C. under normal pressure for 2 hours to obtain an [amorphous polyester (low molecular weight polyester) resin].

(Production example 2)
<Synthesis of crystalline polyester resin>
A 5-liter four-necked flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was charged with the following materials and reacted at 160° C. for 5 hours.
-material-
・1,6-Hexanediol 2,300 parts by mass ・Fumaric acid 2,530 parts by mass ・Trimellitic anhydride 291 parts by mass ・Hydroquinone 4.9 parts by mass Further, after raising the temperature to 200 ° C. and reacting for 1 hour , and 8.3 kPa for 1 hour to obtain a [crystalline polyester resin].

(Production example 3)
<Synthesis of polyester prepolymer>
The following materials were placed in a reactor equipped with a condenser, stirrer, and nitrogen inlet tube, and reacted at 230° C. for 8 hours under normal pressure.
-material-
・Bisphenol A ethylene oxide 2 mol adduct 682 parts by mass ・Bisphenol A propylene oxide 2 mol adduct 81 parts by mass ・Terephthalic acid 283 parts by mass ・Trimellitic anhydride 22 parts by mass ・Dibutyltin oxide 2 parts by mass Further, 10 mmHg to 15 mmHg The reaction was carried out for 5 hours under reduced pressure to obtain [intermediate polyester].
The resulting [intermediate polyester] has a number average molecular weight Mn of 2,100, a weight average molecular weight Mw of 9,500, a glass transition temperature Tg of 55° C., an acid value of 0.5 KOHmg/g, and a hydroxyl value of 51 KOHmg/g. was g.
Next, 410 parts by mass of [intermediate polyester], 89 parts by mass of isophorone diisocyanate, and 500 parts by mass of ethyl acetate are placed in a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen inlet tube, and stirred at 100°C for 5 hours. A [polyester prepolymer] was obtained by allowing time to react.

(Production example 4)
<Production of fine resin particles (A-1) aqueous dispersion (W0-1)>
The following materials were added to a reaction vessel equipped with a stirrer, a heating/cooling device, and a thermometer, and stirred at 200 revolutions/minute for homogenization.
-material-
・Water 3710 parts by mass ・Polyoxyethylene-1-(allyloxymethyl) alkyl ether sulfate ester ammonium (Daiichi Kogyo Seiyaku Co., Ltd., Aqualon KH-1025) 200 parts by mass The homogenized product is heated and placed in the system. After raising the temperature to 75° C., 90 parts by mass of a 10% by mass ammonium persulfate aqueous solution was added, and then the following materials (mixed liquid) were added dropwise over 4 hours.
―Material (mixture)―
・Styrene 450 parts by mass ・Butyl acrylate 250 parts by mass ・Methacrylic acid 300 parts by mass After dropping, the monomer and polyoxyethylene-1-(allyloxymethyl)alkyl ether sulfate ester ammonium are coexisted by aging at 75 ° C. for 4 hours. [Resin fine particle (A-1) dispersion (W0-1)] containing resin (a1), which is a polymer polymer, was obtained.
The volume average primary particle diameter of the fine particles in the resin fine particle (A-1) aqueous dispersion (W0-1) was 15 nm as measured by a dynamic light scattering particle size distribution analyzer (LB).
Part of the resin fine particle (A-1) aqueous dispersion (W0-1) was dried to isolate the resin (a1).
The resin (a1) had a glass transition temperature (Tg) of 53° C. and an acid value of 195 mgKOH/g.

(Production example 5)
<Production of fine resin particles (A-2) aqueous dispersion (W0-2)>
The following materials were added to a reaction vessel equipped with a stirrer, a heating/cooling device, and a thermometer, and stirred at 200 rpm for homogenization.
-material-
・Water 3760 parts by mass ・Polyoxyethylene-1-(allyloxymethyl) alkyl ether sulfate ester ammonium (Daiichi Kogyo Seiyaku Co., Ltd., Aqualon KH-1025) 150 parts by mass After raising the temperature to 75° C., 90 parts by mass of a 10% by mass ammonium persulfate aqueous solution was added, and then the following materials (mixed liquid) were added dropwise over 4 hours.
―Material (mixture)―
・Styrene 430 parts by mass ・Butyl acrylate 270 parts by mass ・Methacrylic acid 300 parts by mass [Resin fine particles (A-2) aqueous dispersion (W0-2)] containing resin (a2), which is a polymer polymer, was obtained.
The volume-average primary particle diameter of the fine particles in the fine resin fine particles (A-2) aqueous dispersion (W0-2) was measured in the same manner as in Production Example 4 and found to be 30 nm.
Part of the resin fine particle (A-2) aqueous dispersion (W0-2) was dried to isolate the resin (a2).
The resin (a2) had a glass transition temperature (Tg) of 53° C. and an acid value of 195 mgKOH/g.

(Production example 6)
<Production of fine resin particles (A-3) aqueous dispersion (W0-3)>
The following materials were added to a reaction vessel equipped with a stirrer, a heating/cooling device, and a thermometer, and stirred at 200 revolutions/minute for homogenization.
-material-
・Water 3810 parts by mass ・Polyoxyethylene-1-(allyloxymethyl) alkyl ether sulfate ester ammonium (Daiichi Kogyo Seiyaku Co., Ltd., Aqualon KH-1025) 100 parts by mass Heat to raise the system temperature to 75 ° C. After warming, 90 parts by mass of a 10% by mass ammonium persulfate aqueous solution was added, and then the following materials (mixed liquid) were added dropwise over 4 hours.
―Material (mixture)―
・Styrene 400 parts by mass ・Butyl acrylate 300 parts by mass ・Methacrylic acid 300 parts by mass [Resin fine particles (A-3) aqueous dispersion (W0-3)] containing resin (a3), which is a polymer polymer, was obtained.
The volume-average primary particle diameter of the fine particles in the fine resin fine particles (A-3) aqueous dispersion (W0-3) was measured in the same manner as in Production Example 4 and found to be 45 nm.
Part of the resin fine particle (A-3) aqueous dispersion (W0-3) was dried to isolate the resin (a3).
The resin (a3) had a glass transition temperature (Tg) of 53° C. and an acid value of 195 mgKOH/g.

(Production Example 7)
<Production of fine resin particles (B-1) aqueous dispersion (W-1)>
Add the following materials to a reaction vessel equipped with a stirrer, a heating and cooling device, and a thermometer, add 0.267 parts by mass of tertiary butyl hydroperoxide (Perbutyl H, manufactured by NOF Corporation), and heat. The temperature in the system was raised to 70°C.
-material-
Aqueous dispersion (W0-1) of fine resin particles (A-1): 667 parts by mass Water: 248 parts by mass Next, the following materials (mixed liquid) were added dropwise over 2 hours.
―Material (mixture)―
・Styrene 43.3 parts by mass ・Butyl acrylate 17.5 parts by mass ・2-Ethylhexyl acrylate 5.8 parts by mass ・1 wt% ascorbic acid aqueous solution 18.0 parts by mass After dropping, aging at 70 ° C. for 4 hours Using the resin (a1) in the resin fine particle (A-1) aqueous dispersion (W0-1) as a seed, the resin (a1-1), which is a polymer obtained by copolymerizing the above monomer, and the resin (a1) are mixed in the same particle. [resin fine particles (B-1) aqueous dispersion (W-1)] contained as a constituent component in the above was obtained.
The volume average primary particle diameter of the fine resin particles (B-1) in the aqueous dispersion (W-1) of the fine resin particles (B-1) was measured in the same manner as in Production Example 4 and found to be 17 nm.

The resin fine particle (B-1) aqueous dispersion (W-1) contains the resin fine particle (B-1) containing the resin (a1-1) and the resin (a1) as constituent components in the same particle. It was confirmed as follows.
Specifically, 2 parts by mass of gelatin (Cook Gelatin, Morinaga Milk Industry Co., Ltd.) was added to 15 parts by mass of water heated to 95°C to 100°C, dissolved, and air-cooled to 40°C. Resin fine particles (B-1) and aqueous dispersion (W-1) were mixed at a mass ratio of 1:1, stirred well, and cooled at 10° C. for 1 hour to prepare a cured gel.
This gel was subjected to an ultramicrotome (Ultramicrotome UC7, FC7, manufactured by Leica Microsystems) to prepare a section with a thickness of 80 nm while controlling the temperature at -80 ° C., and then a 2% by mass ruthenium tetroxide aqueous solution for 5 minutes. After performing phase staining, it was confirmed by observing with a transmission electron microscope (manufactured by Hitachi Technologies, Ltd., H-7100).

(Production Example 8)
<Production of fine resin particles (B-2) aqueous dispersion (W-2)>
Add the following materials to a reaction vessel equipped with a stirrer, a heating and cooling device, and a thermometer, add 0.267 parts by mass of tertiary butyl hydroperoxide (Perbutyl H, manufactured by NOF Corporation), and heat. The temperature in the system was raised to 70°C.
-material-
Aqueous dispersion (W0-1) of fine resin particles (A-1): 667 parts by mass Water: 248 parts by mass Next, the following materials (mixed liquid) were added dropwise over 2 hours.
―Material (mixture)―
・Styrene 43.3 parts by mass ・Butyl acrylate 23.3 parts by mass ・1 wt% ascorbic acid aqueous solution 18.0 parts by mass Using the resin (a1) in W0-1) as a seed, the resin (a1-2), which is a polymer obtained by copolymerizing the above-mentioned monomers, and the resin (a1) are included in the same particle as constituent components [resin fine particles (B- 2) Aqueous dispersion (W-2)] was obtained.
The volume-average primary particle diameter of the fine resin particles (B-2) in the aqueous dispersion (W-2) of the fine resin particles (B-2) was measured in the same manner as in Production Example 4 and found to be 17 nm.
The resin fine particle (B-2) aqueous dispersion (W-2) contains resin fine particles (B-2) containing the resin (a1) and the resin (a1-2) as constituent components in the same particle. It was confirmed by the same method as in Production Example 7.

(Production Example 9)
<Production of fine resin particles (B-3) aqueous dispersion (W-3)>
Add the following materials to a reaction vessel equipped with a stirrer, a heating and cooling device, and a thermometer, add 0.267 parts by mass of tertiary butyl hydroperoxide (Perbutyl H, manufactured by NOF Corporation), and heat. The temperature in the system was raised to 70°C.
-material-
Aqueous dispersion (W0-1) of fine resin particles (A-1): 667 parts by mass Water: 248 parts by mass Next, a mixture of the following materials was added dropwise over 2 hours.
―Material (mixture)―
・Styrene 43.3 parts by mass ・2-Ethylhexyl acrylate 23.3 parts by mass ・1 wt% ascorbic acid aqueous solution 18.0 parts by mass Using the resin (a1) in the dispersion (W0-1) as a seed, the resin (a1-3), which is a polymer obtained by copolymerizing the monomer, and the resin (a1) are included in the same particle as constituent components [resin fine particles (B-3) Aqueous dispersion (W-3)] was obtained.
The volume-average primary particle diameter of the fine resin particles (B-3) in the aqueous dispersion (W-3) of the fine resin particles (B-3) was measured in the same manner as in Production Example 4 and found to be 17 nm.
The resin fine particle (B-3) aqueous dispersion (W-3) contains resin fine particles (B-3) containing resin (a1) and resin (a1-3) as constituent components in the same particle. It was confirmed by the same method as in Production Example 7.

(Production Example 10)
<Production of fine resin particles (B-4) aqueous dispersion (W-4)>
Add the following materials to a reaction vessel equipped with a stirrer, a heating and cooling device, and a thermometer, add 0.267 parts by mass of tertiary butyl hydroperoxide (Perbutyl H, manufactured by NOF Corporation), and heat. The temperature in the system was raised to 70°C.
-material-
Aqueous dispersion (W0-2) of fine resin particles (A-2): 667 parts by mass Water: 248 parts by mass Next, the following materials (mixed liquid) were added dropwise over 2 hours.
―Material (mixture)―
・Styrene 43.3 parts by mass ・Butyl acrylate 17.5 parts by mass ・2-Ethylhexyl acrylate 5.8 parts by mass ・1 wt% ascorbic acid aqueous solution 18.0 parts by mass After dropping, aging at 70 ° C. for 4 hours Using the resin (a2) in the resin fine particle (A-2) aqueous dispersion (W0-2) as a seed, the resin (a2-1), which is a polymer obtained by copolymerizing the above monomers, and the resin (a2) are mixed in the same particle. [Resin Fine Particles (B-4) Aqueous Dispersion (W-4)] was obtained.
The volume average primary particle diameter of the resin fine particles (B-4) in the resin fine particle (B-4) aqueous dispersion (W-4) was measured in the same manner as in Production Example 4 and found to be 34 nm.
The resin fine particle (B-4) aqueous dispersion (W-4) contains resin fine particles (B-4) containing the resin (a2-1) and the resin (a2) as constituent components in the same particle. It was confirmed by the same method as in Production Example 7.

(Production Example 11)
<Production of fine resin particles (B-5) aqueous dispersion (W-5)>
Add the following materials to a reaction vessel equipped with a stirrer, a heating and cooling device, and a thermometer, add 0.267 parts by mass of tertiary butyl hydroperoxide (Perbutyl H, manufactured by NOF Corporation), and heat. The temperature in the system was raised to 70°C.
-material-
Aqueous dispersion (W0-3) of fine resin particles (A-3): 667 parts by mass Water: 248 parts by mass Next, the following materials (mixed liquid) were added dropwise over 2 hours.
―Material (mixture)―
・Styrene 43.3 parts by mass ・Butyl acrylate 23.3 parts by mass ・1 wt% ascorbic acid aqueous solution 18.0 parts by mass Using the resin (a3) in W0-3) as a seed, the resin (a3-1), which is a polymer obtained by copolymerizing the monomer, and the resin (a3) are included in the same particle as constituent components [resin fine particles (B- 5) Aqueous dispersion (W-5)] was obtained.
The volume-average primary particle diameter of the fine resin particles (B-5) in the aqueous dispersion (W-5) of the fine resin particles (B-5) was measured in the same manner as in Production Example 4 and found to be 52 nm.
The resin fine particle (B-5) aqueous dispersion (W-5) contains resin fine particles (B-5) containing resin (a3-1) and resin (a3) as constituent components in the same particle. It was confirmed by the same method as in Production Example 7.

(Production Example 12)
<Production of Resin Fine Particles (B-6) Aqueous Dispersion (W-6) to Resin Fine Particles (B-9) Aqueous Dispersion (W-9)>
In Production Example 11, resin fine particles (B-6), aqueous dispersion (W-6), and butyl acrylate 23 were produced by changing the total amount of 2-ethylhexyl acrylate to 23.3 parts by mass of butyl acrylate. Aqueous dispersion (W-7) of fine resin particles (B-7) produced by changing 75% of 3 parts by mass to 2-ethylhexyl acrylate, and 50% of 23.3 parts by mass of butyl acrylate to 2-ethyl Resin fine particles (B-8) aqueous dispersion (W-8) produced by changing to hexyl acrylate, and produced by changing 25% of 23.3 parts by mass of butyl acrylate to 2-ethylhexyl acrylate was used as resin fine particle (B-9) aqueous dispersion (W-9).
The volume average primary particle diameters of the resin fine particle (B-6) aqueous dispersion (W-6) to the resin fine particle (B-9) aqueous dispersion (W-9) were measured in the same manner as in Production Example 4. , the resin fine particles (B-6) were 56 nm, the resin fine particles (B-7) were 54 nm, the resin fine particles (B-8) were 54 nm, and the resin fine particles (B-9) were 52 nm.
The resin fine particle (B-6) aqueous dispersion (W-6) to the resin fine particle (B-9) aqueous dispersion (W-9) are prepared using the resin (a3) in (W0-3) as a seed. Resin fine particles (B-6) to resin fine particles (B- 9) was confirmed by the same method as in Production Example 7.

(Production Example 13)
<Production of polyester resin fine particles>
A polyester resin was produced as follows.
[Production of polyester resin]
A mixture of 1,600 parts of terephthalic acid, 633 parts of isophthalic acid, 1,149 parts of ethylene glycol, and 1,510 parts of neopentyl glycol was heated in an autoclave at 260° C. for 5 hours to effect an esterification reaction. Next, 0.262 part of germanium dioxide as a catalyst was added, the temperature of the system was raised to 280° C. over 30 minutes, and the pressure of the system was gradually reduced to 0.1 Torr after 1 hour. The polycondensation reaction was further continued under these conditions, and after 5 hours the system was brought to normal pressure with nitrogen gas, the temperature of the system was lowered, and when the temperature reached 260°C, 50 parts of isophthalic acid and 26.6 parts of trimellitic anhydride were added. and stirred at 255° C. for 30 minutes, and discharged in a sheet form. Then, after sufficiently cooling to room temperature, the mixture was pulverized with a crusher, and a [polyester resin] fraction having an opening of 1 to 6 mm was obtained using a sieve.
[Production of crystalline polyester resin fine particle dispersion]
In a jacketed 2L glass container, 200 parts of polyester resin, 35 parts of ethylene glycol mono-n-butyl ether, polyvinyl alcohol ("Unitika Poval" 050G manufactured by Unitika) 0.5% by mass aqueous solution (hereinafter, PVA-1) 450 parts , and N,N-dimethylethanolamine corresponding to 1.2 times the equivalent of the total amount of carboxyl groups contained in the [polyester resin] is added, and this is an open system desktop type homodisper (Tokushu Kika Kogyo Co., Ltd. When the mixture was stirred at 6,000 rpm using a TK Robomix manufactured by TK Corporation, no sedimentation of the resin particles was observed at the bottom of the container, confirming that the resin particles were in a completely suspended state. Therefore, this state was maintained, and after 10 minutes, hot water was passed through the jacket for heating. When the temperature inside the vessel reached 68° C., the mixture was stirred at 7,000 rpm, and the temperature inside the vessel was kept at 68 to 70° C. and further stirred for 20 minutes to obtain a milky white uniform aqueous dispersion. Next, cold water was run through the jacket, and the mixture was cooled to room temperature while stirring at 3,500 rpm, and filtered using a stainless steel filter (635 mesh, plain weave) to obtain fine polyester resin particles having a volume average primary particle size of 55 nm. [Crystalline polyester resin fine particle dispersion] was obtained. In the filtration process, almost no resin particles remained on the filter.

(Production Example 14)
<Production of Resin Fine Particles (B') Aqueous Dispersion>
The following materials were added to a reactor equipped with a stirrer and a thermometer and stirred at 400 rpm for 15 minutes.
-material-
・Water 683 parts by mass ・Sodium salt of methacrylic acid ethylene oxide adduct sulfate ester (ELEMINOL RS-30, manufactured by Sanyo Chemical Industries, Ltd.) 11 parts by mass ・Styrene 138 parts by mass ・Methacrylic acid 138 parts by mass ・Ammonium persulfate 1 part by mass The resulting emulsion was heated to raise the temperature in the system to 75° C., and reacted for 5 hours.
Furthermore, 30 parts by mass of a 1% by mass ammonium persulfate aqueous solution was added, and the mixture was aged at 75° C. for 5 hours to obtain [resin fine particles (B′) (vinyl resin: sodium salt of styrene-methacrylic acid-ethylene oxide methacrylic acid adduct sulfate ester. (copolymer) aqueous dispersion] was obtained.
The volume average primary particle diameter of the resin fine particle (B') aqueous dispersion in the resin fine particle (B') aqueous dispersion was measured in the same manner as in Production Example 4 and was 140 nm.

(Example 1)
<Preparation of masterbatch (MB)>
The following materials were added to a container and mixed using a Henschel mixer (manufactured by Nippon Coke Industry Co., Ltd.).
-material-
・Water 1200 parts by mass ・Carbon black (Printex 35, DBP oil absorption = 42 mL/100 mg, pH = 9.5, manufactured by Evonik Dexa) 540 parts by mass ・[Amorphous polyester resin] 1200 parts by mass Two rolls of the mixture After kneading at 150° C. for 30 minutes, the mixture was rolled, cooled, and pulverized with a pulperizer to obtain a [masterbatch].

<Preparation of Wax Dispersion>
In a container set with a stirring rod and a thermometer, 50 parts by mass of paraffin wax (manufactured by Nippon Seiro Co., Ltd., HNP-9, hydrocarbon wax, melting point 75 ° C., SP value 8.8) as a release agent, and 450 parts by mass of ethyl acetate was charged, the temperature was raised to 80° C. while stirring, the temperature was maintained at 80° C. for 5 hours, the temperature was cooled to 30° C. in 1 hour, and a bead mill (Ultra Viscomil, Aimex Co., Ltd.) was used. , a liquid feed rate of 1 kg/hr, a disk peripheral speed of 6 m/sec, zirconia beads with a diameter of 0.5 mm and 80% by volume of zirconia beads, and three passes to obtain a [wax dispersion].

<Preparation of crystalline polyester resin dispersion>
50 parts by mass of the crystalline polyester resin of Production Example 2 and 450 parts by mass of ethyl acetate were charged into a vessel equipped with a stirring rod and a thermometer, heated to 80°C while stirring, and maintained at 80°C for 5 hours. After that, it was cooled to 30°C in 1 hour, and filled with 80% by volume of zirconia beads with a diameter of 0.5 mm using a bead mill (Ultra Viscomill, manufactured by Aimex Co., Ltd.) at a liquid feeding speed of 1 kg/hr, a disk peripheral speed of 6 m/sec. , and 3 passes to obtain [Crystalline Polyester Resin Dispersion].

<Preparation of oil phase>
78 parts by mass of amorphous polyester resin, 70 parts by mass of crystalline polyester resin dispersion, 25 parts by mass of wax dispersion, and 16 parts by mass of masterbatch were placed in another container equipped with a thermometer and a stirrer, and solidified. Ethyl acetate was added so as to give a concentration of 30% by mass, and the solution was sufficiently dissolved by stirring. Next, using a TK-type homomixer (manufactured by Primix Co., Ltd.), the mixture was stirred at a rotation speed of 8,000 rpm to uniformly dissolve and disperse.
Furthermore, isophoronediamine (IPDA) was added in an amount such that the molar ratio (NH2/NCO) of the amino group of IPDA and the isocyanate group of the [intermediate polyester] was 0.98, and a TK-type homomixer was used. Stirred at 8,000 rpm for 15 seconds. Next, 30 parts by mass of the prepared [intermediate polyester] was added to a 50% by mass ethyl acetate solution, and the mixture was stirred at 8,000 rpm for 30 seconds using a TK homomixer to obtain [oil phase 1].

<Preparation of aqueous phase>
In a container equipped with a stirrer and a thermometer, 75 parts by mass of ion-exchanged water, 1 part by mass of sodium carboxymethylcellulose, and 48.5% by mass aqueous solution of sodium dodecyldiphenyl ether disulfonate (eleminol MON-7, Sanyo Chemical Industries, Ltd.) ) and 5 parts by mass of ethyl acetate are mixed and stirred, and further, an amount equivalent to 1.6 parts by mass of the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] and [resin fine particles (B-1) Aqueous dispersion (W-1)] was added in an amount equivalent to 0.8 parts by mass of solid content to prepare an aqueous phase solution. This was designated as [aqueous phase 1].

<Emulsification and solvent removal>
Add 50 parts by mass of [aqueous phase 1] to a container containing 29 parts by mass of [oil phase 1], mix and stir with a TK homomixer at a rotation speed of 8,000 rpm for 2 minutes, and then mix for 20 minutes to [emulsify]. Slurry 1] was obtained.
Next, [Emulsified slurry 1] was put into a container equipped with a stirrer and a thermometer, and after the solvent was removed at 30°C for 8 hours, it was aged at 45°C for 4 hours to obtain [Dispersed slurry 1]. .

<Washing and drying>
After 100 parts by mass of the obtained [dispersion slurry 1] was filtered under reduced pressure to obtain a [filter cake], the following operations were performed.
(1): 100 parts by mass of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (12,000 rpm for 10 minutes), and then filtered.
(2): 100 parts by mass of a 10% by mass sodium hydroxide aqueous solution was added to the filtered cake obtained after (1), mixed with a TK homomixer (at 12,000 rpm for 30 minutes), and filtered under reduced pressure.
(3): 100 parts by mass of 10% by mass hydrochloric acid was added to the filtered cake after (2), mixed with a TK homomixer (12,000 rpm for 10 minutes) and then filtered.
(4): 300 parts by mass of ion-exchanged water was added to the filtered cake after (3), mixed with a TK homomixer (12,000 rpm for 10 minutes), and then filtered.
The above operations (1) to (4) were performed twice to obtain [filter cake after washing treatment].
The obtained [filtered cake after washing] was dried at 45° C. for 48 hours in a circulating dryer, and sieved with a mesh having an opening of 75 μm to obtain [toner base particles 1].

<External addition processing>
To 100 parts by weight of the obtained [toner base particles 1], 1.0 parts by weight of colloidal silica (Aerosil R972, manufactured by Nippon Aerosil Co., Ltd.) was mixed as an external additive in a sample mill. Toner 1] was obtained.

(Example 2)
In the <adjustment of the aqueous phase> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous An amount equivalent to 0.8 parts by mass of the solid content of the dispersion (W-1)], an amount equivalent to 1.9 parts by mass of the solid content of the [resin fine particle (A-1) aqueous dispersion (W0-1)], and [ [Toner Base Particles 2] was obtained in the same manner as in Example 1, except that the resin fine particle (B-1) aqueous dispersion (W-1)] was changed to a solid content equivalent to 0.5 parts by mass. . [Toner 2] was produced in the same manner as in Example 1 using the obtained [Toner base particles 2].

(Example 3)
In <Aqueous phase adjustment> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] was equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous dispersion The amount equivalent to 0.8 parts by mass of the solid content of Liquid (W-1)] was changed to the equivalent of 2.4 parts by mass of the solid content of [Resin Fine Particles (B-7) Aqueous Dispersion (W-7)]. [Toner Base Particles 3] was obtained in the same manner as in Example 1 except for the above. [Toner 3] was produced in the same manner as in Example 1 using the obtained [Toner base particles 3].

(Example 4)
In the <adjustment of the aqueous phase> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous The solid content equivalent to 0.8 parts by mass of dispersion liquid (W-1)] was changed to the solid content equivalent to 2.4 parts by mass of [resin fine particle (B-8) aqueous dispersion (W-8)]. [Toner Base Particles 4] was obtained in the same manner as in Example 1 except for the above. [Toner 4] was produced in the same manner as in Example 1 using the obtained [Toner base particles 4].

(Example 5)
In the <adjustment of the aqueous phase> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous The solid content equivalent to 0.8 parts by mass of dispersion (W-1)] was changed to the solid content equivalent to 2.4 parts by mass of [resin fine particle (B-9) aqueous dispersion (W-9)]. [Toner Base Particles 5] was obtained in the same manner as in Example 1 except for the above. [Toner 5] was produced in the same manner as in Example 1 using the obtained [Toner base particles 5].

(Example 6)
In the <adjustment of the aqueous phase> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous An amount equivalent to 0.8 parts by mass of the solid content of the dispersion (W-1)], an amount equivalent to 1.6 parts by mass of the solid content of the [resin fine particle (A-2) aqueous dispersion (W0-2)], and [ [Toner Base Particles 6] was obtained in the same manner as in Example 1, except that the resin fine particle (B-4) aqueous dispersion (W-4)] was changed to a solid content equivalent to 0.8 parts by mass. . [Toner 6] was prepared in the same manner as in Example 1 using the obtained [Toner base particles 6].

(Example 7)
In the <adjustment of the aqueous phase> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous Example 1, except that the solid content equivalent of 0.8 parts by mass of [Dispersion (W-1)] was changed to the solid content equivalent of 2.4 parts by mass of [Crystalline polyester resin fine particle dispersion]. [Toner base particles 7] were obtained in the same manner.
[Toner 7] was produced in the same manner as in Example 1 using the obtained [Toner base particles 7].

(Example 8)
In the <adjustment of the aqueous phase> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous Dispersion (W-1)] in an amount equivalent to 0.8 parts by mass of solid content was changed to an amount equivalent to 2.4 parts by mass of solid content in [resin fine particle (B′) aqueous dispersion]. [Toner base particles 8] were obtained in the same manner as in 1.
[Toner 8] was produced in the same manner as in Example 1 using the obtained [Toner base particles 8].

(Comparative example 1)
In the <adjustment of the aqueous phase> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous The solid content equivalent to 0.8 parts by mass of dispersion (W-1)] was changed to the solid content equivalent to 2.4 parts by mass of [resin fine particle (B-5) aqueous dispersion (W-5)]. [Toner Base Particles 9] was obtained in the same manner as in Example 1 except for the above.
[Toner 9] was produced in the same manner as in Example 1 using the obtained [Toner base particles 9].

(Comparative example 2)
In the <adjustment of the aqueous phase> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous The amount equivalent to 0.8 parts by mass of the solid content of the dispersion (W-1)] was changed to the amount equivalent to 2.4 parts by mass of the solid content of the [resin fine particle (B-6) aqueous dispersion (W-6)]. [Toner Base Particles 10] was obtained in the same manner as in Example 1 except for the above.
[Toner 10] was produced in the same manner as in Example 1 using the obtained [Toner base particles 10].

(Comparative Example 3)
In the <adjustment of the aqueous phase> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous An amount equivalent to 0.8 parts by mass of the solid content of the dispersion (W-1)], an amount equivalent to 1.9 parts by mass of the solid content of the [resin fine particle (A-1) aqueous dispersion (W0-1)], and [ [Toner base particles 11] were obtained in the same manner as in Example 1, except that the solid content of the fine resin particles (B-2) aqueous dispersion (W-2)] was changed to 0.5 parts by mass equivalent. .
[Toner 11] was produced in the same manner as in Example 1 using the obtained [Toner base particles 11].

(Comparative Example 4)
In the <adjustment of the aqueous phase> of Example 1, the solid content of [resin fine particles (A-1) aqueous dispersion (W0-1)] equivalent to 1.6 parts by mass, and [resin fine particles (B-1) aqueous An amount equivalent to 0.8 parts by mass of the solid content of the dispersion (W-1)], an amount equivalent to 1.9 parts by mass of the solid content of the [resin fine particle (A-1) aqueous dispersion (W0-1)], and [ [Toner Base Particles 12] was obtained in the same manner as in Example 1, except that the resin fine particle (B-3) aqueous dispersion (W-3)] was changed to a solid content equivalent to 0.5 parts by mass. .
[Toner 12] was produced in the same manner as in Example 1 using the obtained [Toner base particles 12].

<Production of carrier>
To 100 parts by mass of toluene, 100 parts by mass of a silicone resin (organo straight silicone), 5 parts by mass of γ-(2-aminoethyl)aminopropyltrimethoxysilane, and 10 parts by mass of carbon black are added and dispersed for 20 minutes with a homomixer. Then, a resin layer coating liquid was prepared.
Using a fluidized bed coating apparatus, the surface of 1,000 parts by mass of spherical magnetite having a volume average particle diameter of 50 μm was coated with the resin layer coating solution to prepare a [carrier].

<Production of developer>
Using a ball mill, 5 parts by mass of each [toner] and 95 parts by mass of [carrier] were mixed to prepare each [developer].

Next, using each toner and each developer thus obtained, various characteristics were evaluated as follows. The results are shown in Tables 1-3.

<Evaluation of granulation>
Each [toner] is dispersed in water, and the volume average primary particle size and particle size distribution (volume average primary particle size/number average particle size) are measured with a Coulter counter "Multisizer III" (manufactured by Beckman Coulter, Inc.). The granulation performance was evaluated according to the following criteria. The granulation performance was obtained when the particle size distribution was 1.20 or less when the volume average primary particle diameter of the toner was 5.0 μm to 5.9 μm. is preferred.
[Evaluation Criteria for Granulation]
○: Particle size distribution is 1.20 or less ×: Particle size distribution is 1.21 or more

<Evaluation of Low Temperature Fixability>
Toner (powder) was placed uniformly on the surface of paper (Type 6200, A4 size, manufactured by Ricoh Co., Ltd.) so as to be 0.8 mg/cm ² , and the fixing speed (heating roller peripheral speed) was applied to the pressure roller. The cold offset generation temperature (MFT) was measured when passing under the conditions of 213 mm/sec and a fixing pressure (pressure roller pressure) of 10 kg/cm ² . It should be noted that the lower the temperature at which cold offset occurs, the better the low-temperature fixability.
The method of placing the toner (powder) on paper uses a printer without a heat fixing device. As long as the toner (powder) can be uniformly placed on the surface of paper with the above weight density, there is no particular limitation, and other methods may be used.
[Evaluation Criteria for Low Temperature Fixability]
◎: Minimum fixing temperature is 130°C or less ○: Minimum fixing temperature is greater than 130°C and 135°C or less △: Minimum fixing temperature is greater than 135°C and 140°C or less ×: Minimum fixing temperature is greater than 140°C

<Evaluation of Toner Adhesion>
The force between two particles (Fp) when each toner is compressed at 160 kN/m ² can be measured using a powder layer compression/tensile characteristics measuring device Agrobot (manufactured by Hosokawa Micron Corporation).
The force between two particles (Fp) is obtained by filling a fixed amount of each toner into a cylindrical cell divided into upper and lower halves under the following conditions, holding each toner under a pressure of 160 kN/m ² , and then lifting the upper cell. It is calculated from the maximum tensile breaking force when the powder layer is broken by pressing, the height of the powder layer during compression, the inner diameter of the cell, the average particle size of the toner, the true density of the toner, and the amount of toner.
Specifically, the measurement is performed under the conditions shown below, and the force between two particles (Fp) calculated by the attached application software is expressed as the force between two particles (Fp) when the toner is compressed at 160 kN/m ² . was evaluated according to the criteria of Incidentally, the measurement was carried out while the toner was conditioned at 23° C. and 53% RH for 24 hours.
-Measurement condition-
・Toner amount: 8.00g±0.02g
・Environmental temperature: 25±2℃
・Humidity: 30±5% RH
・Cell inner diameter: 25 mm
・Cell temperature: 25°C
・Spring wire diameter: 1.0 mm
・Compression speed: 0.1mm/sec
・Compressive load: 8 kg (pressure: 160 kN/m2)
・Compression holding time: 60 sec
・Tensile speed: 0.6mm/sec
・Tension sampling start time: 0 sec
・ Tensile sampling time: 25 sec
[Evaluation Criteria for Toner Adhesion]
◎: Best Fp ≤ 200
○: Good 200 < Fp ≤ 300
△: Acceptable 300 < Fp ≤ 500
×: NG Broken failure

<Evaluation of filming resistance>
Each developer is placed in an image forming apparatus (RICOH MPC 6003, manufactured by Ricoh Co., Ltd.), and a solid image with an adhesion amount of 0.4 mg/cm ² is exposed, developed, and transferred to paper (manufactured by Ricoh Co., Ltd.). , Type 6200, A4 size plate), 2,000 sheets were continuously fed, and contamination of the latent image carrier and charging device was visually observed and evaluated according to the following criteria.
[Evaluation Criteria for Filming Resistance]
A: No contamination on the latent image carrier and no filming on the charging device O: Slight contamination on the latent image carrier and filming on the charging device △: Stain on the latent image carrier and film on the charging device Poor: Slight contamination on the latent image carrier and slight filming on the charging device, causing early abnormal images

<Comprehensive judgment>
Based on the results of each evaluation item, judgment is made according to the following criteria.
[Evaluation criteria]
◎: Three or more of the evaluation items "◎"
〇: There are two or less “◎” among the evaluation items, and there are no “△” or “×” △: Any of the evaluation items is “△”
×: Any of the evaluation items is “×”

From the results in Tables 1 to 3, it was found that Examples 1 to 8 of the present invention exhibited excellent performances in all of granulation properties, low-temperature fixability, adhesive strength, and anti-filming properties.
In Comparative Example 1, the amount of aggregates on the surface of the toner base was large, and the low-temperature fixability was slightly lowered.
In Comparative Example 2, the amount of aggregates on the surface of the toner base is small, and the spacer effect is weak, so the adhesion is inferior.
Comparative Example 3 has a larger standard deviation than Comparative Example 1, and Comparative Example 4 has a larger standard deviation than Comparative Example 2. As a result, the toner base was unevenly exposed, resulting in poor adhesion.

Embodiments of the present invention are, for example, as follows.
<1> A toner having a plurality of fine resin particles observed by a scanning electron microscope (SEM) on the surface of a toner base particle, wherein the toner contains at least a resin and a wax, and is the smallest particle among the fine resin particles. A toner characterized in that, when the major axis of R is defined as R, and the resin fine particles having a major axis of 3R or more are aggregated, the percentage of the surface of the toner base particles occupied by the aggregates is 15% or more and 60% or less. is.
<2> The toner according to <1>, wherein the fine resin particles include a core resin and a shell resin covering at least a portion of the surface of the core resin.
<3> The toner according to <2>, wherein the shell resin contains a styrene-acrylic resin.
<4> The toner according to any one of <1> to <3>, wherein the aggregate accounts for 15% or more and 35% or less of the surface of the toner base particles.
<5> Any one of <1> to <4>, wherein the standard deviation of the distance between adjacent resin fine particles that are not in contact with each other on the surface of the toner base particles is 500 nm or less. toner.
<6> The toner according to any one of <1> to <5>, wherein the resin fine particles have a volume average primary particle size of 10 nm or more and 100 nm or less.
<7> A toner containing unit containing the toner according to any one of <1> to <6>.
<8> An image forming apparatus comprising the toner storage unit according to <7>.
<9> An electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier; and developing the electrostatic latent image formed on the electrostatic latent image carrier with toner. and a developing step of forming a toner image that is a visible image, wherein the toner is the toner according to any one of <1> to <6>. .
<10> A toner manufacturing method for manufacturing the toner according to any one of <1> to <6>, wherein composite particles are formed by adhering fine resin particles to the surfaces of toner base particles. and a removing step of removing at least part of the fine resin particles from the composite particles.
<11> The method for producing a toner according to <10>, wherein the removing step is a step of washing with a basic aqueous solution.

The toner according to any one of <1> to <6>, the toner containing unit according to <7>, the image forming apparatus according to <8>, the image forming method according to <9>, According to the toner manufacturing method described in any one of <10> to <11>, various problems in the conventional art can be solved and the object of the present invention can be achieved.

REFERENCE SIGNS LIST 1 shell resin 2 core-shell resin 3 fine resin particles 4 toner base particles 101 latent image carrier 102 charging device 103 exposure device 104 developing device 105 recording paper 107 cleaning unit 108 transfer roller 160Y sub hopper (yellow)
160C sub hopper (cyan)
160M sub hopper (magenta)
160K sub hopper (black)
180Y image forming unit (yellow)
180C image forming unit (cyan)
180M image forming unit (magenta)
180K image forming unit (black)
210 Paper feed section 211 Paper feed cassette 212 Paper feed roller 220 Transport section 221 Roller 222 Timing roller 223 Paper discharge roller 224 Paper discharge tray 230 Imaging section 231Y Photoconductor drum (yellow)
231C photoreceptor drum (cyan)
231M photoreceptor drum (magenta)
231K photoreceptor drum (black)
232Y charger (yellow)
232C charger (cyan)
232M charger (magenta)
232K charger (black)
233 exposure unit 233a light source 233bY polygon mirror (yellow)
233bC polygon mirror (cyan)
233bM polygon mirror (magenta)
233bK polygon mirror (black)
234Y Toner Bottle (Yellow)
234C Toner Bottle (Cyan)
234M Toner Bottle (Magenta)
234K Toner Bottle (Black)
236Y Cleaner (Yellow)
236C cleaner (cyan)
236M cleaner (magenta)
236K Cleaner (Black)
240 Transfer Unit 241 Drive Roller 242 Driven Roller 243 Intermediate Transfer Belt 244 Primary Transfer Roller 244Y Primary Transfer Roller (Yellow)
244C primary transfer roller (cyan)
244M primary transfer roller (magenta)
244K primary transfer roller (black)
245 Secondary opposed roller 246 Secondary transfer roller 250 Fixing device 251 Fixing belt 252 Pressure roller L Laser P Paper

JP 2019-099809 A JP 2019-143128 A JP 2013-011644 A JP 2009-098194 A JP 2014-178528 A

Claims (11)

A toner having a plurality of fine resin particles observed by a scanning electron microscope (SEM) on the surface of toner base particles,
The toner contains at least resin and wax,
When the major diameter of the smallest particle among the resin fine particles is R, and the resin fine particles having a major diameter of 3R or more are regarded as aggregates, the ratio of the aggregates occupying the surface of the toner base particles is 15% or more and 60% or less. A toner characterized by: 2. The toner according to claim 1, wherein the fine resin particles comprise a core resin and a shell resin covering at least a part of the surface of the core resin. 3. The toner of claim 2, wherein said shell resin contains a styrene-acrylic resin. 4. The toner according to any one of claims 1 to 3, wherein the aggregate accounts for 15% or more and 35% or less of the surface of the toner base particles. 5. The toner according to any one of claims 1 to 4, wherein the standard deviation of the distance between adjacent resin fine particles that are not in contact with each other and are present on the surface of the toner base particles is 500 nm or less. 6. The toner according to any one of claims 1 to 5, wherein the volume average primary particle size of the resin fine particles is 10 nm or more and 100 nm or less. A toner containing unit containing the toner according to any one of claims 1 to 6. An image forming apparatus comprising the toner storage unit according to claim 7 . an electrostatic latent image forming step of forming an electrostatic latent image on an electrostatic latent image carrier; and developing the electrostatic latent image formed on the electrostatic latent image carrier with toner. a developing step to form a toner image that is a visual image;
An image forming method, wherein the toner is the toner according to any one of claims 1 to 6. A toner manufacturing method for manufacturing the toner according to any one of claims 1 to 6,
a composite particle forming step of forming composite particles by adhering fine resin particles to the surfaces of toner base particles;
and a removing step of removing at least part of the fine resin particles from the composite particles. 11. The method of manufacturing a toner according to claim 10, wherein the removing step is a step of washing with a basic aqueous solution.

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