JP3168384B2 - Electrophotographic toner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic toner which is used in a method for visualizing an electrostatic latent image and has excellent low-temperature fixability and storage stability during heating.

[0002]

2. Description of the Related Art In order to visualize an electric or magnetic latent image on a recording medium, an image is formed by adsorbing electroconductive or magnetically sensitive fine particles such as toner onto the latent image to form a visible image. There is a way. A representative example thereof is electrophotography, and many methods are known, for example, as described in US Pat. No. 2,297,691.
In this electrophotography, a photoconductive substance is generally used to form an electric latent image on a photoreceptor by various means, and then the latent image is developed using toner to form a toner image. If necessary, the toner image is transferred to a transfer material such as paper, and then the toner image is fixed to the transfer material using heat, pressure, or solvent vapor to obtain a copy.

[0003] In recent years, the above-mentioned technology has achieved high printing quality,
Because of its quietness, it has been used for output means such as computers and word processors, so-called printers. When used in the environment described above,
Not only high printing quality and quietness,
Further, characteristics such as printing speed, energy consumption, long-term image stability, environmental stability and running cost are required.

The toner used in the above-mentioned printers and copiers is a fine particle composed of a main component resin and a magnetic substance, a colorant such as carbon black, a dye and a pigment, and waxes. The range is 30 μm.
Generally, a toner having a desired particle diameter is obtained by mixing and melting a coloring agent composed of a dye or pigment or a magnetic substance in a thermoplastic resin, uniformly dispersing the coloring agent, and then pulverizing and classifying. It is manufactured as. This method is relatively stable as a technology, and the management of each material and each process can be performed relatively easily. However, since the contents are exposed to the fracture surface, the above-mentioned wax for lowering the melting point such as wax is used. The components and the components for mold release cannot be contained sufficiently enough to be effective, and there is a drawback that sufficient low-temperature fixing cannot be achieved. In addition, since the toner obtained by the above-described pulverization method has a different shape and a relatively wide particle size distribution, when a predetermined charge is applied to the toner, triboelectric charging is not performed uniformly and printing is performed. There was a drawback that the characteristics became unstable.

In recent years, a method for producing a toner by a polymerization method has been proposed as an improvement over the above-mentioned disadvantages.
These are described, for example, in JP-B-36-10231, JP-B-51-14895, JP-A-53-17735, JP-A-53-17736 and JP-A-53-17736.
No. 17737. According to the above-described method, a substance to be included in the toner such as a binder resin, a coloring agent such as a dye or a pigment, for example, a magnetic substance, carbon black, a charge control agent, a release agent such as wax or silicone oil, is used as needed. The polymerizable monomer is dissolved or dispersed in a polymerizable monomer together with a polymerization initiator and a dispersant to form a polymerizable composition, and dispersed in an aqueous continuous phase containing a dispersion stabilizer using a dispersing apparatus to form a dispersion of fine particles. This dispersion is polymerized and solidified to obtain toner particles having a desired particle size and composition.

The above-mentioned method is expected to have effects such as energy saving, improvement of process yield, and cost reduction because there is no process such as pulverization and classification. In many cases, the particle size distribution fluctuates and the particle size distribution is relatively widened, and the toner particle size is stabilized to a desired particle size required for obtaining a high-quality and high-definition copy image. It was difficult. Also, particularly, toner particles formed by the suspension polymerization method often contain low molecular weight components which cause deterioration of storage stability during heating according to the reaction rate of the monomer, and thus low-temperature fixability. It was difficult to achieve a balance between storage stability and storage stability under heat.

[0007] Regarding the toner produced by any of the above-described production methods, it is necessary to lower the fixing temperature of the toner in order to solve the problem of low-temperature fixing. The most effective way to lower the fixing temperature is to lower the glass transition point of the binder resin used for the toner. However, a binder resin formed by a method such as solution polymerization, suspension polymerization, or emulsion polymerization often contains a relatively low molecular weight component. For this reason, in order to reduce the energy at the time of fixing for obtaining a copied image or the time at which the first copy is obtained, the glass transition point of the binder resin is lowered by adjusting the resin composition and the molecular weight composition. In addition, if the thermal storage stability of the toner material is reduced, or if the residual toner on the photoreceptor is continuously cleaned particularly by the cleaning blade due to the presence of the low molecular weight component, the toner aggregates near the blade to cause an image defect. There was something.

Further, even if fixing properties at a low temperature are simply achieved by adjusting the glass transition point, in a printer which is required to save space and consume less power, the melt viscosity of the toner material decreases during fixing. The offset phenomenon that occurs because it is too much and contaminates the non-image part of the image receiving material,
Since it is practically impossible to improve by means such as silicone oil application, it has been necessary to separately improve the low-temperature fixability and improve the offset resistance.

[0009]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and is excellent in low-temperature fixability, hot storage stability, and durability, and can provide a high-resolution copy image. It is intended to provide a toner for use.

[0010]

The object of the present invention described above is achieved by the following constitution. That is, the present invention is, heavy
By polymerizing a compatible monomer in a hydrophilic organic solvent
A polymerized toner to be formed, wherein the hydrophilic organic solvent
Contains a polymer compound and a colorant,
Compatible monomer is 0.5 to 5 times the weight of the polymer compound
Content of the polymer compound and the hydrophilic organic solvent
The concentration with respect to the medium is 10% by weight or more,
And polymer compounds are well soluble in the hydrophilic organic solvent
And the polymer formed by polymerization is the hydrophilic organic
Under the condition that the polymerized toner does not dissolve in the solvent,
Is formed, further, the polymerized toner has a molecular weight distribution having at least one maxima contains at least a binder resin and a colorant, wherein the binder resin is in a gel permeation chromatogram, Even the lowest
The peak molecular weight of the peak present on the molecular weight side is from 4,000 to
10,00 0, and it relates to a toner for electrophotography, wherein the molecular weight of 1,000 or less components is less than 5 wt%.

[0011]

The present invention is characterized in that the binder resin contained in the polymerized toner has a molecular weight distribution having at least one or more maximum values, and the molecular weight distribution at such a maximum value is extremely narrow. It is assumed that. By controlling the maximum value of the molecular weight distribution of the binder resin as low as possible and using the binder resin excluding low molecular weight components, for example, compared to a polymer having the same peak molecular weight and composition, A highly elastic binder resin can be formed. The low molecular weight component as described above not only lowers the storage stability during heating, but also causes contamination of the blade in an electrophotographic process in which residual toner is removed from the photoreceptor by rubbing with a cleaning blade or the like. A phenomenon such as deterioration of developability and image characteristics, deformation or deterioration due to rubbing in the vicinity of the blade, or adhesion to each other, resulting in granulation and reduction of uniform developability occurs. In this case, by using the binder resin of the present invention, it is possible to provide high durability in an electrophotographic process while realizing low-temperature fixability and storage stability during heating.

According to the present invention, specifically, the production of a polymerized toner is carried out in a high-concentration polymer solution to obtain desired molecular weight characteristics,
It is characterized in that toner particles having a particle size are obtained. As a result of intensive studies, the present inventors have found that, according to the method of the present invention, as compared with the conventional method, the particle size distribution is narrower, and the particle size is controlled in the range from submicron scale to several μm, and at the same time, the low molecular weight component It has been found that a toner having a low content can be formed. Further, the fine particle toner formed by the method of the present invention uses a solvent in which a monomer compound and an oligomer component are dissolved and a polymer compound having a sufficiently high molecular weight is precipitated from a homogeneous system. Since a low molecular weight component that degrades the toner is hardly contained in the polymer, the thermal fixing property of the toner composition can be improved while maintaining the storage stability during heating in a good condition.

The above-mentioned polymer solvent specifically refers to a mixture in which a polymer is dissolved in a solvent. Usually, when a polymer is dissolved in a specific solvent, the solvent to be dissolved and the polymer compound interact with each other to form a predetermined range of free space between the polymer chains. This free space can be freely controlled by changing the type of polymer, molecular weight, concentration and type of solvent, and the volume distribution of the free space has considerable uniformity. Therefore, it is presumed that a monomer cluster having a high monomer concentration can be formed by enclosing the polymerizable monomer composition in the free space. It is considered that the free space or the monomer cluster thus formed efficiently forms a toner having a desired particle diameter.

The stability of the above-mentioned monomer clusters depends largely on the concentration and molecular weight of the polymer matrix, and on the matrix / monomer ratio. When the concentration of the polymer matrix is lower than the predetermined concentration, the viscosity for sufficiently stabilizing the cluster cannot be obtained, and thus the particle size is not sufficiently reduced, so that toner particles having a small particle size cannot be obtained. Also, if the matrix concentration is too low relative to the monomer amount, monomer clusters are not suitably formed,
The reaction rate and granulation properties are remarkably reduced, and polymer particles having the molecular weight characteristics and particle diameter of the present invention cannot be produced efficiently.

That is, the present invention is to form a monomer cluster region containing a reactive monomer in a relatively high concentration so that the polymerizable monomer can be diffused relatively easily in this region and the polymerization reaction can proceed favorably. Is made possible. As a result, specifically, for example, Japanese Patent Application Laid-Open No. 61-189
No. 65, JP-A-61-18966, JP-A-6-18
JP-A 1-228458, JP-A-63-304002, JP-A-5-93002, JP-A-5-142
850, JP-A-5-142861, JP-A-5-158279, JP-A-5-181315, etc., to form toner particles having a small particle size more efficiently than the conventional dispersion polymerization method. It is presumed that good particle forming properties are realized even with a polymer resin having a relatively low degree of polymerization.

Therefore, the concentration of the polymer matrix which can be suitably used in the present invention is preferably at least 0.1% with respect to the polymer matrix in order to impart a predetermined viscosity to the medium containing the polymer. It is necessary that the concentration be 5 times by weight or more and 5 times by weight or less. When the monomer is added in an amount of more than 5 times by weight, the monomer cluster is not stabilized, and fine particles cannot be satisfactorily achieved. If the amount is less than 0.5 times by weight, the viscosity of the reaction system tends to increase, and it becomes difficult to add a sufficient amount of monomer. Performance is reduced.

The amount of the polymer matrix used is such that a stable formation of monomer clusters is achieved.
It is necessary to use the toner in an amount of 10% by weight or more based on the solvent used, preferably 10% by weight based on the hydrophilic solvent used in order to efficiently form a toner having a sufficiently small particle size. It is. If the addition amount is lower than the above range, it is not possible to achieve sufficient fine particle formation. As the molecular weight of the above-mentioned polymer matrix, it is preferable that the weight average molecular weight in terms of polystyrene by gel permeation chromatography is in the range of 10,000 to 300,000. By performing the polymerization reaction under the above-described polymer matrix conditions, it is possible to mainly form polymer particles having a size of 0.1 μm to less than 5 μm.

The molecular weight of the toner produced by the production method according to the present invention has a peak molecular weight of 4,000 to 4,000.
A range of 1,000,000 is possible. In the present invention, gel permeation chromatography (GPC) is used as the molecular weight, and the elution time is calibrated using polystyrene as the molecular weight standard. The toner of the present invention achieves the above object by having predetermined molecular weight characteristics. That is, a low molecular weight component is removed in order to improve the fixing property, a molecular weight distribution with a reduced peak molecular weight is given, and a polymer component or a gel component for improving the anti-offset property is introduced as necessary. It has molecular weight characteristics. By having such molecular weight characteristics, it is possible to satisfy both thermal storage stability, fixability, and, if necessary, offset resistance. Further, even if the cleaning blade is constantly rubbed, good durability can be realized without causing aggregation of the toner, and an appropriate copied image can be maintained even after long-term durability.

For this purpose, in the toner of the present invention, the peak molecular weight of the component forming the maximum value on the low molecular weight side of the molecular weight distribution is from 4,000 to 10,000, and the component having a molecular weight of 1,000 or less is 5,000. It is good that it is less than 3% by weight, preferably less than 3% by weight.

When the peak molecular weight corresponding to the lowest molecular weight in the molecular weight distribution is smaller than 4000, the molecular weight component increases, and it tends to be difficult to reduce the component having a molecular weight of 1000 or less to 5% by weight or less. If it exceeds 10,000, the fixability tends to decrease.

Further, in the molecular weight distribution, a molecular weight of 100
When the amount of the component of 0 or less is more than 5% by weight, the storage stability during heat and the durability tend to decrease.

The high molecular weight component, which is optionally introduced into the binder resin of the toner of the present invention, preferably has a peak molecular weight in the range of 30,000 to 1,000,000. When the maximum value or the maximum value of the peak is recognized on the chart, the molecular weight conversion value in the range of 100,000 to 400,000 indicates that the melt viscosity of the toner of the present invention is increased, It is suitable for reducing the offset. In particular, the components on the high molecular weight side do not need to form a clear peak or local maximum value on the GPC chart, and may have a degree that extends from a low molecular weight to a high molecular weight. In this case, the molecular weight of the high molecular weight component is preferably in the range of 100,000 to 1,000,000 in terms of the molecular weight at the high molecular weight end. In addition to the high molecular weight component soluble in the above-mentioned solvent, a component insoluble in the solvent such as a gel may be contained.

When the toner of the present invention is formed by a polymerization method in a polymer matrix dissolved in a hydrophilic organic solvent, various polymer compounds and copolymers can be used as the polymer matrix. Is mentioned. As such a polymer, specifically, for example, polystyrene,
Polyhydroxystyrene, polyhydroxystyrene-acrylate copolymer, hydroxylstyrene-vinyl ether or vinyl ester copolymer, polymethyl methacrylate, phenol novolak resin, cresol novolak resin, styrene-acryl copolymer, vinyl ether copolymer (Specifically, for example, polymethyl vinyl ether, polyethyl vinyl ether, polybutyl vinyl ether, polyisobutyl vinyl ether), polyvinyl alcohol, polyvinyl pyrrolidone,
Polyvinyl acetate, styrene-butadiene copolymer, ethylene-vinyl acetate copolymer, vinyl chloride, polyvinyl acetal, cellulose, cellulose acetate, cellulose nitrate, alkylated cellulose, hydroxyalkylated cellulose (specifically, hydroxymethyl cellulose, hydroxy Propylcellulose), a saturated alkyl polyester resin, an aromatic polyester resin, a polyamide resin, a polyacetal, a polycarbonate resin, or a mixture thereof, or a monomer that forms the above-mentioned polymer compound in any ratio. Copolymers can be mentioned. Among them, preferred are those which dissolve well in the reaction solvent and have no affinity for the produced polymer compound. As the affinity between the polymer compounds, specifically, a solubility parameter of the polymer compound can be used favorably. Such solubility parameters are:
Values obtained from various experiments can be used, or more specifically, for example, in the case of a copolymer, for example, Properties of Polymers.
(DW Van Klevelen, Elsevier
r, 1990).

The difference between the solubility parameter of the matrix resin and the solubility parameter of the polymer constituting the toner to be formed is preferably 0.35 or more in consideration of a preferable particle size range and particle size distribution. ,
In addition, considering the concentration of the polymer matrix used in the present invention, the difference between the solubility parameters is preferably 6.0 or less. If the difference in the solubility parameter exceeds 6.0, it becomes difficult to dissolve the required amount of the polymer matrix in the reaction solvent, and if the difference is less than 0.35, the formed polymer matrix existing in high concentration around the formed toner will be difficult. It will be mixed, and characteristics such as storage stability during heating will be degraded.

As such a reaction solvent, a solvent in which a polymerization product is precipitated as the polymerization proceeds is used. Specifically, for example, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, tertiary butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, isopentyl alcohol, tertiary pentyl alcohol, 1-hexanol, 2- Methyl 1-pentanol, 4-methyl-2-pentanol, 2-ethylbutanol, 1-heptanol, 2-heptanol, 3-heptanol, 2-
Linear or branched aliphatic alcohols such as octanol and 2-ethyl 1-hexanol; pentane, 2-methylbutane, n-hexane, cyclohexane, 2-methylpentane, 2,2-dimethylbutane, 2,3- Dimethylbutane, heptane, n-octane, isooctane,
In addition to aliphatic hydrocarbons such as 2,2,3-trimethylpentane, decane, nonane, cyclopentane, methylcyclopentane, methylcyclohexane, ethylcyclohexane, p-menthane, and bicyclohexyl, aromatic hydrocarbons and halogenated hydrocarbons Examples include hydrogens, ethers, fatty acids, esters, sulfur-containing compounds, and mixtures thereof.

The polymerizable monomers used in the present invention include styrene, o-methylstyrene, m-methylstyrene, p-methoxystyrene, p-ethylstyrene,
styrene monomers such as p-tert-butylstyrene; acrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate, n-propyl acrylate;
Acrylic esters such as isobutyl acrylate, octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate; methacrylic acid, methyl methacrylate, ethyl methacrylate, methacrylic acid N-propyl acrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, etc. Methacrylic acid esters; 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide, etc. Vinyl derivatives, specifically, alkyl vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, n-butyl ether, isobutyl ether; β-chloroethyl vinyl ether, phenyl vinyl ether, p-methylphenyl ether, p-chlorophenyl ether; p
-Bromophenyl ether, p-nitrophenyl vinyl ether, p-methoxyphenyl vinyl ether, 2-
Examples thereof include diene compounds such as vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, N-vinylpyrrolidone, 2-vinylimidazole, N-methyl-2-vinylimidazole, N-vinylimidazole and butadiene.

These monomers can be used alone or as a mixture, and a suitable polymer composition that can obtain preferable characteristics can be selected. In the present invention, as the polymerizable monomer composition, one that becomes insoluble in the solvent used as the polymerization reaction proceeds can be used. Further, the copolymer used in the present invention may be formed from any composition of the above-mentioned monomers, but preferably has a glass transition point in the range of 30 ° C to 100 ° C, Furthermore, in order to satisfy low-temperature fixability and storage stability under heat, the glass transition point is 4%.
Preferably, it is in the range of 0 ° C to 70 ° C.

The melt viscosity characteristics can be adjusted as required by incorporating a high molecular weight component or a gel component into the toner of the present invention. The introduction of such a component is achieved by using a crosslinking agent having two or more polymerizable double bonds per molecule. Specific examples of such a cross-linking agent include, for example, divinylbenzene, aromatic divinyl compounds such as divinylnaphthalene, ethylene glycol diacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate,
Tetraethylene glycol dimethacrylate, 1,3-
Butylene glycol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol diacrylate, neopentyl glycol diacrylate, 1,6
-Hexanediol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol dimethacrylate,
Compounds such as pentaerythritol tetramethacrylate, glycerol acroxydimethacrylate, N, N-divinylaniline, divinyl ether, divinyl sulfide and divinyl sulfone can be mentioned.
More than one kind may be used as appropriate. The amount of the cross-linking component added is preferably 0.5 to 50% by weight based on the monofunctional component, and more preferably 0.5 to 50% in order to satisfy both low-temperature fixability and offset resistance. More preferably, it is added in the range of -30% by weight. Such a crosslinking agent can be previously mixed with the polymerizable mixture, or can be appropriately added during the polymerization as needed.

When forming the toner of the present invention, acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, monobutyl itaconate, monobutyl maleate, a monomer containing phosphoric acid, Are acid phosphooxyethyl methacrylate, acid phosphooxypropyl methacrylate, sulfonic acid group-containing monomers, dimethylaminoethyl acrylate, diethylaminoethyl methacrylate, acroyl morpholine, 2-
Vinyl pyridine, 3-vinyl pyridine, 4-vinyl pyridine, N-vinyl pyrrolidone, 2-vinyl imidazole, N-methyl-2-vinyl imidazole, N-vinyl imidazole, or copolymers of the above-mentioned salts and the like are charged. Can also be adjusted.

As the polymerization initiator used in the present invention, any of those known as radical initiators can be used. Specific examples of such a polymerization initiator include, for example, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, and 1,1′-azobis (cyclohexane- 1-carbonitrile), 2,2′-azobis-4-methoxy-2,
Azo or diazo polymerization initiators such as 4-dimethylvaleronitrile; 2,2′-azobis (2-aminodipropane) dihydrochloride, 2,2′-azobis (N,
Amidine compounds such as N'-dimethyleneisobutylamidine) and 2,2'-azobis (N, N'-dimethyleneisobutylamidine) dihydrochloride; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide And peroxide polymerization initiators such as 2,4-dichlorobenzoyl peroxide and lauroyl peroxide; and persulfate initiators such as potassium persulfate and ammonium persulfate, and mixtures of the above-mentioned initiators. .

In the present invention, known chain transfer agents, specifically, carbon tetrachloride, carbon tetrabromide, ethyl dibromide acetate, ethyl tribromide acetate, ethyl dibromide benzene, ethane dibromide , Halogenated hydrocarbons such as ethane dichloride; hydrocarbons such as diazothioether, benzene, ethylbenzene, and isopropylbenzene; mercaptans such as tertiary decyl mercaptan and n-dodecyl mercaptan; and disulfides such as diisopropylzantogen disulfide. You can also. The concentration of the polymerization initiator used in obtaining the toner of the present invention can be appropriately adjusted in consideration of the molecular weight, yield, and the like of the produced polymer. It can be used in the range of 0.1% to 15% by weight of the total amount,
Suitably, it is in the range from 5% to 12% by weight.

As the colorant of the fine particle toner of the present invention,
Specifically, in addition to carbon black, an organic coloring agent, specifically, for example, C.I. I. Direct Red 1, C.I. I. Basic Red 1, C.I. I. Modant Red 30, C.I.
I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Acid Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Modant Blue 7, C.I. I. Direct Green 6, C.I.
I. Basic Green 4, C.I. I. Dyes such as Basic Green 6; Cadmium Yellow, Mineral First Yellow, Navel Yellow, Naphthol Yellow S, Hansa Yellow G, Permanent Yellow NC
G, tartrazine lake, molybdenum orange GTR,
Benzidine Orange G, Cadmium Red 4R, Watching Red Calcium Salt, Brilliant Carmine 3
B, Fast Violet B, Methyl Violet Lake, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Quinacridone, Rhodamine Lake, Phthalocyanine Blue, Fast Sky Blue, Pigment Green B, Macalite Green Lake, Final Yellow Green G, etc. Can be mentioned.

Further, in the present invention, a magnetic toner can be obtained by using a magnetic substance as a coloring agent. Such a colorant can be dispersed in the polymerizable mixture in advance, or after synthesizing only polymer fine particles, dispersing the fine particles in a solution in which necessary components are dissolved or dispersed, and coloring the polymerized toner. It can also be.

The polymerized toner formed by using the above-described method and polymer can contain various additives in order to impart more favorable developer properties. Such various additives can be mixed and dissolved in the polymerizable mixture in advance, or can be added after synthesizing fine particles.

For the purpose of controlling the chargeability of the toner of the present invention, a charge control agent can be added. As the charge control agent, any of a positive charge control agent or a negative charge control agent can be used. Specifically, for example, a nigrosine dye, a triphenylmethane dye, a quaternary ammonium salt, an amine or Imine compounds, and polymers, salicylic acid, or metal compounds of alkyl salicylic acid,
Examples include gold-containing monoazo dyes, polymers having a carboxylic acid or sulfonic acid functional group, humic acids such as nitrohumin, and salts.

In forming the fine particle toner of the present invention,
Fine particles are generated as the reaction proceeds. The obtained fine particles are repeatedly washed with a reaction solvent or another suitable solvent. At this time, a separating means such as a centrifuge may be used to improve the washing efficiency. After washing, the obtained toner is filtered, dried and crushed to obtain fine particles, and a predetermined additive is appropriately added to obtain the toner of the present invention. At this time, as a separation and drying means, a spraying method such as spray drying can be used.

The particle diameter of the fine particle toner obtained by the production method of the present invention can be adjusted to a number average particle diameter of 0.1 to 6 μm by appropriately changing the type, concentration, molecular weight and composition of the polymer matrix. However, in order to achieve the object of high image quality and high definition of the electrophotographic image, the thickness is preferably in the range of 0.5 to 5 μm. In the present invention, the number average particle diameter is used as the particle diameter, and a microscopic method was used as a measuring method thereof. That is, the toner particles are measured with an electron microscope at 100
After magnifying the image by a factor of 00 and photographing the image, the maximum chord length in the horizontal direction was actually measured for 300 toners, and the number average was calculated. In addition, the above-described steps can be performed using an image analysis device or the like. Specific examples of such an image analyzer include Luzex 3 (Nireco Co., Ltd.).

The toner of the present invention can be added with a low-temperature fluidizing component such as a plasticizer and wax in order to improve the releasability when combined with a hot roll fixing device. Examples of the above-mentioned wax include paraffin, polyolefin-based wax and modified products thereof, for example, oxides and grafted products, higher fatty acids and metal salts thereof, higher aliphatic alcohols, higher aliphatic esters, and aliphatic amide waxes. No. These waxes are used in the ring and ball method (JI
Those having a softening point by SK2531) in the range of 30 to 130 ° C are preferred. The above-mentioned waxes are preferably added to the fine particles of the present invention in the form of fine powder.

Since the toner of the present invention is finer than conventional toners, it can be added with various fluidity improvers to provide a developer having improved development characteristics and transportability. Examples of such a fluidity improver include fine powder of silica, fine powder of titanium oxide, alumina and the like.
Such a fluidity improver is particularly crushed for the toner of the present invention, and has a specific surface area of 300 m ² or more by nitrogen adsorption measured by the BET method in the range of titanium oxide, silica,
It is preferable to use fine powder such as alumina. The amount of addition depends on the particle size of the toner, but is preferably in the range of 0.5 to 50% by weight.

The toner of the present invention comprises an iron powder carrier (EFV).
(200/300: manufactured by Powder Tech Co., Ltd.) is preferably 2 μC / g or more in absolute value. If it is lower than this, sufficient development cannot be performed,
Image formation becomes difficult. FIG. 1 shows a device for measuring the amount of triboelectric charge used in the present invention, the details of which will be described later.

There are various methods for obtaining the charge amount required for forming an image by frictionally charging the toner of the present invention. For example, the toner may be mixed with carrier particles and used as a two-component developer. it can.

Specific examples of the carrier powder usable in the present invention include ferromagnetic metals such as iron powder, cobalt powder and nickel powder; irons such as ferrite, magnetite and hematite; A compound containing an element exhibiting magnetism can be given. Still further, a magnetic substance-dispersed carrier in which the above-described magnetic substance is dispersed in a binder can be used.

Various types of surface coatings may be applied to the carrier particles for the purpose of adjusting resistance, spent resistance, impact resistance, and triboelectric charging. As the polymer compound used as the surface coating agent, various compounds can be mentioned, and specifically, for example, polystyrene,
Polymethyl methacrylate, phenol novolak resin, phenol resin, epoxy resin, alkyd resin,
Melamine resin, cresol novolak resin, styrene
Acrylic copolymer, fluorinated acrylic resin, perfluorocarbon polymer, silicone acrylic copolymer, silicone resin, vinyl ether copolymer (specifically, for example, polymethyl vinyl ether, polyethyl vinyl ether, polybutyl vinyl ether, polyisobutyl vinyl ether) , Polyvinyl alcohol, polyvinyl acetate,
Styrene-butadiene copolymer, ethylene-vinyl acetate copolymer, vinyl chloride, polyvinyl acetal, cellulose, cellulose acetate, cellulose nitrate, alkylated cellulose, hydroxyalkylated cellulose (specifically, hydroxymethyl cellulose, hydroxypropyl cellulose), Examples thereof include saturated alkyl polyester resins, aromatic polyester resins, polyamide resins, polyacetals, polycarbonate resins, and mixtures thereof.

The average particle size of the carrier particles used in the present invention is preferably in the range of 10 to 100 μm. Further, from the viewpoint of high image quality, the thickness is preferably in the range of 10 to 60 μm. When the carrier particle size is less than 10 μm, carrier adhesion to the photoreceptor easily occurs. If the particle size is larger than 60 μm, high image quality cannot be achieved. In the present invention, the number average particle diameter is used as the carrier particle diameter, and a microscopic method was used as a measuring method thereof. That is, the carrier particles were magnified 1,000 times with an electron microscope, and after photographing an image, the maximum horizontal chord length was measured for 300 carriers, and the number average was calculated. In addition, the above-described steps can be performed using an image analysis device or the like.

When the toner of the present invention is used as a two-component developer by mixing it with the above-described carrier particles, the mixing ratio of the toner in the developer depends on the carrier particle size, but it is 0.5%. Preferably it is in the range from 10% by weight to 10% by weight.

The method of measuring the triboelectric charge used in the present invention will be described in detail. The toner of the present invention and an iron powder carrier (EFV)
200/300: manufactured by Powder Tech Co., Ltd.) so that the toner content is 1% by weight.
Mix for seconds. FIG. 1 is an explanatory view of a triboelectric charge measuring device used in the present invention. A mixture of toner and carrier particles whose frictional charge is to be measured is placed in a metal measurement container 12 having a 500-mesh conductive screen 13 at the bottom, and a metal cover 14 is placed. At this time, the total weight of the measurement container is weighed to be W ₁ (g). Next, it is placed on the suction device 11 (at least the portion in contact with the measurement container 12 is an insulator), suction is performed from the suction port 17, and the air volume control valve 16 is adjusted to set the pressure of the vacuum gauge 15 to 250 mmHg. This state is enough (about 1 minute)
Suction is performed to remove the toner by suction. Electrometer 1 at this time
The potential of No. 9 is set to V (volt). Here, reference numeral 18 denotes a capacitor having a capacity of C (μF). Further, the weight of the whole measuring container after the suction is measured and defined as W ₂ (g). The triboelectric charge amount Q (μC / g) can be obtained by the following equation.

Q (μC / g) = (C × V) × (W ₁ −W ₂ ) ⁻¹

[0049]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited by the embodiments. The parts used in the examples are all parts by weight, and the solubility parameters of the polymer forming the polymer matrix and the formed polymer fine particles are those calculated by the above-described method. The molecular weight of the formed polymer compound is determined by Showex GPC SYST
Using EM-11 type, the measurement was performed by setting the column to KF-80MX2 and the column temperature to 40 ° C. The calculation of the molecular weight was determined by calibrating the elution time using a molecular weight calibration curve prepared by a monodisperse polystyrene standard sample (for example, PL Polymer Calibration Kit SM-10 of PL Polymer Laboratories).

Example 1 A 1-liter four-necked flask equipped with a reflux condenser, a thermometer, and a capillary for introducing nitrogen was composed of 540 parts of methanol, 60 parts of n-hexane, and 75 parts of polymethylvinyl ether (weight average molecular weight: 54,000). The solution was charged. Thereafter, styrene monomer 100 parts n-butyl acrylate 41 parts divinylbenzene 2.0 parts carbon black 5.0 parts 2,2-azobisisobutyronitrile 9.6 parts 3,5-di-tert-butylsalicylic acid metal complex The mixture of 3 parts was charged into the flask and mixed well. Next, the reaction mixture was refluxed for 6 hours in a nitrogen stream, and the reaction mixture obtained after the reaction was repeatedly decanted with methyl alcohol using a centrifugal separator to wash polymethyl vinyl ether as a polymer matrix. Thereafter, the obtained toner was further dried in vacuum to obtain particles having an average particle size of 2.7 μm. The molecular weight of the copolymer obtained at this time is formed from at least two or more molecular weight components tailed to a weight average molecular weight of about 270,000, and the peak molecular weight on the low molecular weight side is 8,200. The component having a molecular weight of 1,000 or less was 0.15%.

2 parts of this toner was crushed and treated with BE.
0.1 parts of titanium oxide having a T value of 350 m ² was mixed with a Henschel mixer, and fine titanium oxide powder was externally added. Further, this toner was mixed with 98 parts of a ferrite core having a particle diameter of 25 μm coated with a styrene-acrylic copolymer to prepare a two-component developer.

A laser printer manufactured by Canon was remodeled for a two-component development process, and the Vp of an alternating electric field was developed for fine particle development.
An electrostatic image is developed on a photoreceptor using the above-mentioned developer in a device for examination optimized for p, frequency, and waveform, and the image on the photoreceptor is adhesively transferred by an adhesive sheet, and then is applied on a smooth paper surface. After fixing, the disturbance of the 600-line image was evaluated by linearity with respect to the set area ratio of the image density of 16 gradations. As a result, good image reproducibility was obtained from the highlight region to the shadow region.

Further, an external fixing machine is used in which a solid image is formed on the above-mentioned photoreceptor, transferred to an image receiving paper, and then heated using a ceramic heating element from the inner surface of the cylindrical sheet having Teflon on its surface. Then, when the temperature on the image receiving paper was set to 90 ° C. and the thermal fixing characteristics were observed, good thermal fixing characteristics were obtained. The evaluation of the heat fixing property was performed by observing the melting state of the toner under a microscope and visually evaluating the melting state. At this time, there was no stain on the non-image portion due to the offset.

Further, when the toner was left to stand at 50 ° C. for 3 days, the toner aggregation was observed. As a result, no increase in the particle size due to the aggregation was observed, indicating good storage stability during heating.

The above toner was used at 23 ° C. and 50 ° C.
When a cleaning durability test was performed on 10,000 sheets in an environment of% RH, good durability was obtained without toner aggregation near the cleaning blade.

The production conditions in each example are shown in Table 1, and the characteristics of the obtained polymer fine particles and toner are shown in Table 2.

Examples 2 and 3 Evaluations were made in the same manner as in Example 1 except that toners having the characteristics shown in Table 1 were used. As a result, a copied image having good resolution was obtained. The obtained toner exhibited good low-temperature fixability and storage stability during heating. Table 2
Describes the production conditions, molecular weight, particle size, and image evaluation results of the produced toner.

Example 4 In a 1-liter four-necked flask equipped with a reflux condenser, a thermometer, and a capillary for introducing nitrogen, 540 parts of methanol, 60 parts of n-hexane, and 100 parts of polymethylvinyl ether (weight average molecular weight: 54,000) were used. The solution was charged. Then, styrene monomer 100 parts n-butyl acrylate 35.1 parts 2-ethylhexyl acrylate 25.2 parts divinylbenzene 3.0 parts 2,2-azobisisobutyronitrile 12.0 parts 3,5-di-tertiary A mixture consisting of 3 parts of a metal butylsalicylate was charged into the flask and mixed well. The reaction mixture was then refluxed for 6 hours in a stream of nitrogen. Thereafter, 25 parts of a dispersion in which 20% by weight of carbon black was dispersed in methyl alcohol was added, and the mixture was further refluxed for 4 hours. The reaction mixture obtained after the reaction was repeatedly decanted with methyl alcohol using a centrifuge to wash and remove polymethyl vinyl ether as a polymer matrix. Thereafter, the obtained toner was further dried under vacuum to obtain colored particles having an average particle size of 2.5 μm.
Further, the molecular weight of the copolymer obtained at this time is formed from at least two or more molecular weight components tailed to a weight average molecular weight of about 180,000, and the low molecular weight side has a peak molecular weight of 6,800 and a molecular weight of 1800. , 00
The component of 0 or less was 2.8%.

[0059] 2 parts of the toner are crushed and treated with BE.
0.1 parts of titanium oxide having a T value of 350 m ² was mixed with a Henschel mixer, and fine titanium oxide powder was externally added. A developer was formed from this toner in the same manner as in Example 1. When evaluation was performed in the same manner as in Example 1 using this developer, a good image was obtained. The production conditions in each example are shown in Table 1, and the characteristics and evaluation results of the obtained toner are shown in Table 2.

Example 5 A 1-liter four-necked flask equipped with a reflux condenser, a thermometer, and a capillary for introducing nitrogen was charged with a solution comprising 600 parts of methanol and 250 parts of polyhydroxystyrene (weight average molecular weight: 20,000). Then, styrene monomer 100 parts n-butyl acrylate 41 parts carbon black 5.0 parts divinylbenzene 2.0 parts 2,2-azobisisobutyronitrile 9.5 parts 3,5-di-tert-butylsalicylic acid metal complex The mixture of 3 parts was charged into the flask and mixed well. Next, the reaction mixture was polymerized in the same manner as in Example 1. Thereafter, the obtained toner was further dried under vacuum to obtain colored particles having an average particle size of 3.8 μm. The molecular weight of the copolymer obtained at this time was 28 by weight average molecular weight.
It was formed from at least two or more molecular weight components tailed to about 000, and the low molecular weight side had a peak molecular weight of 7,000, and the components having a molecular weight of 1,000 or less were 0.2%.

[0061] 2 parts of this toner was subjected to BE
0.07 parts of titanium oxide having a T value of 350 m ² was mixed with a Henschel mixer, and fine titanium oxide powder was externally added. 3 parts of this toner was mixed with 97 parts of a carrier obtained by coating a ferrite core having an average particle diameter of 25 μm with a styrene-acryl resin having an appropriate triboelectric charge amount to form a developer. Evaluation was performed in the same manner as in Example 1 using this developer, and good results were obtained. Table 1 shows the manufacturing conditions in each example.
And the characteristics of the obtained toner are shown in Table 2.

Example 6 In a 1-liter four-necked flask equipped with a reflux condenser, a thermometer, and a capillary for introducing nitrogen, 540 parts of methanol, 60 parts of n-hexane, and 60 parts of polymethyl vinyl ether (weight average molecular weight: 54,000) were used. The solution was charged. Thereafter, styrene monomer 100 parts n-butyl acrylate 41 parts divinylbenzene 2.0 parts C.I. I. Pigment Blue 15: 3 5.0 parts Di-t-butylsalicylic acid metal compound 5.0 parts 2,2-azobisisobutyronitrile 10.0 parts did. Next, the reaction mixture was refluxed for 6 hours in a nitrogen stream, and the reaction mixture obtained after the reaction was repeatedly decanted with methyl alcohol using a centrifuge to wash and remove polymethyl vinyl ether as a polymer matrix. Thereafter, the obtained toner was further dried under vacuum to obtain particles having an average particle diameter of 2.3 μm. The molecular weight of the obtained copolymer was 280,000 in terms of weight average molecular weight.
It is formed from at least two or more molecular weight components tailed to a degree, the peak molecular weight on the low molecular weight side is 7.300, and the component with a molecular weight of 1,000 or less is 0.1.
2%.

2 parts of this toner was subjected to BE
0.11 part of titanium oxide having a T value of 350 m ² was mixed with a Henschel mixer, and fine titanium oxide powder was externally added. 2 parts of this toner was mixed with 98 parts of a ferrite carrier having an average particle size of 25 μm coated with a styrene-acryl resin having suitable triboelectric properties, and premixed with a Turbula mixer to obtain a developer.

Canon full color copier CLC-50
The electrostatic image was developed using the above-mentioned developer in a device for examination, which was modified to optimize the Vpp, frequency and waveform of the alternating electric field for developing fine particles.

After the image on the photoreceptor was adhesively transferred by an adhesive sheet, the image was fixed on a smooth paper surface, and the disturbance of the 600-line image was evaluated by linearity with respect to the set area ratio of the image density of 16 gradations. . As a result, good image reproducibility was obtained from the highlight region to the shadow region.

After a solid image is formed on the photoreceptor and transferred to an image receiving paper, the temperature on the image receiving paper is reduced to 90 ° C. by using an external fixing machine having a fixing roller made of silicone rubber, the surface of which is Teflon-coated. When the heat fixing property was observed at a setting of ℃, good heat fixing properties were obtained. Table 1 shows the characteristics of the obtained toner, and Table 2 shows the evaluation results.

COMPARATIVE EXAMPLE 1 A styrene-n-butyl acrylate copolymer (coagulation composition ratio: 76.5%) was placed in a 2 liter four-neck separable flask equipped with a reflux condenser, a thermometer, and a capillary for introducing nitrogen by a solution polymerization method. 23.5 (weight ratio to charge) and a peak molecular weight of 10,200 were obtained. At this time, the component having a molecular weight of 1,000 or less was 3.8%. A mixture of the following composition using this polymer: styrene-n-butyl acrylate copolymer 100 parts carbon black 5 parts 3,5-di-tert-butylsalicylic acid metal complex 2 parts was premixed, followed by melt kneading, Then, it was pulverized and classified to obtain a resin powder having a weight average particle size of 8.5 μm.
A specific surface area of 200 m ² / g by the BET method is applied to this resin powder.
Was externally added to obtain a toner. To 7 parts of this externally added toner, 93 parts of a ferrite carrier coated with a styrene-acrylic resin and having an average particle diameter of 45 μm were mixed to obtain a developer.

When this developer was evaluated in the same manner as in Example 1, the fixing property was sufficient, but the offset phenomenon occurred and the image receiving paper was contaminated. In addition, molecular weight 1,0
Since a relatively low molecular weight component of 00 or less was present in a relatively large amount, aggregation of particles due to blocking was observed, and the fluidity of the developer was reduced. Also, due to the relatively large particle size, sufficient resolution could not be obtained. Further, when a durability test was further performed on 10,000 sheets, the toner was repeatedly rubbed in the vicinity of the cleaning blade, so that the toner was aggregated, so that the toner could not be uniformly supplied on the developing sleeve, and a stripe was formed on the solid image. -Like image defects were observed. Table 2 shows the results.

Comparative Example 2 A solution consisting of 600 parts of methyl alcohol and 18 parts of polyacrylic acid (weight average molecular weight 270,000) was charged into a 1-liter four-necked flask equipped with a reflux condenser, a thermometer, and a capillary for introducing nitrogen. . Thereafter, a mixture of 100 parts of styrene monomer, 31 parts of n-butyl acrylate, 2.0 parts of divinylbenzene, 5.0 parts of carbon black, and 2.0 parts of 2,2-azobisisobutyronitrile was charged into the flask, Mix well. Next, the reaction mixture was refluxed for 6 hours in a nitrogen stream, and the reaction mixture obtained after the reaction was repeatedly decanted with methyl alcohol using a centrifugal separator to wash and remove polyacrylic acid as a polymer matrix. Thereafter, the obtained toner was further dried under vacuum to obtain toner particles having an average particle size of 7.5 μm. Further, the molecular weight of the copolymer obtained at this time is formed from at least two or more molecular weight components tailed to a weight average molecular weight of about 480,000, of which the low molecular weight side peak is 98,000 in molecular weight. The content of components having a molecular weight of 1,000 or less was 0.06%.

[0070] 5 parts of this toner was crushed and treated with BE.
0.05 parts of titanium oxide having a T value of 200 m ² was mixed with a Henschel mixer, and silica fine powder was externally added. Further, this toner was mixed with 95 parts of a ferrite carrier having an average particle size of 45 μm coated with a styrene-acryl resin having a suitable triboelectric property to obtain a developer.

When this developer was evaluated in the same manner as in Example 1, a copied image having inferior high resolution was obtained. When the storage stability under heat and the low-temperature fixability were evaluated in the same manner as in Example 1, good characteristics were obtained as to the storage stability under heat, but the molecular weight of the low molecular weight peak was large, and the molecular weight of the high molecular weight component was high. However, it did not show sufficient fixability due to its high value. Further, since the particle size of the toner is relatively large, sufficient resolution cannot be obtained. Table 2 shows the results.
It describes in.

Comparative Example 3 In a 3 liter four-necked flask equipped with a reflux condenser, a thermometer and a capillary for introducing nitrogen, 540 parts of ethyl alcohol, 60 parts of n-hexane, and 200 parts of polymethyl vinyl ether (weight average molecular weight: 42,000) Solution. Thereafter, a mixture consisting of 64 parts of styrene monomer, 19.6 parts of n-butyl acrylate, 1.0 part of divinylbenzene, 4.8 parts of carbon black, and 6.0 parts of 2,2-azobisisobutyronitrile was charged into the flask. And mixed well. Next, the reaction mixture was refluxed for 6 hours in a nitrogen stream, and the reaction mixture obtained after the reaction was repeatedly decanted with methyl alcohol using a centrifuge to wash and remove polymethyl vinyl ether as a polymer matrix. As a result, the obtained solid was not a particle but a bulk polymer, and could not be evaluated. This is because the amount of the polymerizable monomer added is too low relative to the matrix resin,
Further, it is considered that the monomer cluster was not formed satisfactorily because the viscosity of the reaction system was too high, and the polymer was precipitated without sufficiently proceeding the polymerization.

Comparative Example 4 100 parts of styrene monomer, 30.6 parts of n-butyl acrylate, 2.0 parts of divinylbenzene, 4.8 parts of carbon black, in a 3-liter four-necked flask equipped with a reflux condenser, a thermometer, and a capillary for introducing nitrogen. A mixture consisting of 6.0 parts of 2,2-azobisisobutyronitrile was charged into the flask and mixed well. Then, 600 parts of ion-exchanged water containing tricalcium diphosphate was added to the reaction mixture, sufficiently dispersed with a homogenizer, and then heated to react at 60 ° C. in a nitrogen stream. After completion of the reaction, the suspension was cooled and hydrochloric acid was added to add
Tricalcium phosphate was dissolved, and the reaction mixture was repeatedly decanted and washed with ion-exchanged water using a centrifugal separator. After drying, toner particles having an average particle diameter of 7.3 μm were obtained. Further, the molecular weight of the copolymer obtained at this time is formed of at least two or more molecular weight components tailed to a molecular weight of about 300,000, of which the low molecular weight side peak is 7,500 in molecular weight, and the molecular weight is 7,500. The component of 1,000 or less was 5.6%.

[0074] 5 parts of this toner were subjected to BE
0.05 parts of titanium oxide having a T value of 200 m ² was mixed with a Henschel mixer, and silica fine powder was externally added. Further, this toner was mixed with 95 parts of a ferrite carrier having an average particle diameter of 45 μm coated with a styrene-acryl resin having a suitable triboelectric property to obtain a two-component developer.

When this developer was evaluated in the same manner as in Example 1, the fixability was sufficiently good. However, since a large amount of a low molecular weight component having a molecular weight of 1,000 or less was present in a large amount, the developer was blocked. Agglomeration of the particles was severe and aggregates were observed, indicating insufficient blocking properties. Also, due to the relatively large particle size, sufficient resolution could not be obtained. Further, when a durability test was further performed on 10,000 sheets, the toner was repeatedly rubbed in the vicinity of the cleaning blade, so that the toner was aggregated, so that the toner could not be uniformly supplied on the developing sleeve, and a stripe was formed on the solid image. -Like image defects were observed. Further, the coefficient of friction between the cleaning blade and the photosensitive drum increased, and the blade was inverted, resulting in poor cleaning. This is presumed to be due to the presence of a large amount of the low molecular weight component, the low molecular weight component accumulated on the blade, and the aggregate was formed by the accumulation. Table 2 shows the results.

[0076]

[Table 1]

[0077]

[Table 2]

[0078]

According to the present invention, it is possible to provide a polymerized toner for electrophotography which is excellent in resolving power and low-temperature fixability, and has good storage stability during heating and durability.

[Brief description of the drawings]

FIG. 1 shows a measuring device used for measuring a triboelectric charge amount used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Suction machine 12 Measuring container 13 Conductive screen 14 Lid 15 Vacuum gauge 16 Air flow control valve 17 Suction port 18 Condenser 19 Electrometer

Continuation of the front page (56) References JP-A-62-191858 (JP, A) JP-A-63-223014 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9 / 08

Claims (2)

(57) [Claims] 1. A polymerizable monomer is polymerized in a hydrophilic organic solvent.
The polymerized toner formed by performing the above, in the hydrophilic organic solvent, a polymer compound and a colorant
The polymerizable monomer is contained in the polymer compound.
0.5 to 5 times by weight of the polymer
The concentration of the compound in the hydrophilic organic solvent is 10% by weight or more
Wherein the polymerizable monomer and the polymer compound have the hydrophilic property.
Soluble in organic solvents and the weight formed by polymerization
The condition that the coalescence does not dissolve in the hydrophilic organic solvent is also required.
And the polymerized toner is formed, and the polymerized toner further contains at least a binder resin and a colorant.
The binder resin has a molecular weight distribution having at least one or more maximum values in a gel permeation chromatogram, and is present on the lowest molecular weight side.
Electrophotographic toner, wherein the peak molecular weight peaks Ri Oh <br/> in 4,000～10,00 0, and molecular weight of 1,000 or less components is less than 5 wt%. Wherein said polymerizable monomer, toner for electrophotography according to claim 1, characterized in that it contains a polymerizable monomer containing two or more at least ethylenically unsaturated bond.