JP2003114548A - toner - Google Patents

Abstract

(57) [Problem] To provide a toner having higher durability without causing adhesion to a developing blade and toner fusion to a developing roll even in a non-magnetic one-component developing system. A toner comprising a binder resin, a charge adjusting resin, a colorant and an external additive, wherein the charge adjusting resin is represented by the formula (I): (Wherein R ¹ represents a hydrogen atom or a methyl group) 60 to 97% by weight of a monomer represented by the formula (II): (In the formula, R ² is a hydrogen atom or a methyl group, and R ³ has 1 carbon atom.
1 to 33 represents a monomer represented by
% By weight and formula (III): (Wherein R ⁴ represents a hydrogen atom or a methyl group, R ⁵ and R ⁶ each represent an alkyl group having 1 to 4 carbon atoms) or a quaternized product thereof containing 2 to 35% by weight. A toner comprising a quaternary ammonium base-containing copolymer obtained by a process including a polymerization process of a monomer mixture, and containing negatively chargeable organic fine particles as an external additive.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method or the like.

[0002]

2. Description of the Related Art It has an excellent positive charging property, and even when it is used in a non-magnetic one-component developing system, there is no fog on the photosensitive member.
As a toner having excellent image density and excellent durability, a positively chargeable full-color toner containing a quaternary ammonium salt group-containing copolymer which is a charge control resin and hydrophobic silica (Japanese Patent Laid-Open No. 2000-338724). Issue)
Alternatively, a positively chargeable toner in which polytetrafluoroethylene is externally added using a nigrosine dye as a charge control agent (JP-A-9-127727) has been reported.

However, in the former case, toner fusion to the developing roll is likely to occur, and in the latter case, deposits on the developing blade are likely to occur, so that the positively chargeable toner for non-magnetic one-component development which is more durable. Is required.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a toner having more excellent durability even in a non-magnetic one-component developing system without causing deposits on a developing blade or toner fusion on a developing roll. The purpose is to do.

[0005]

The present inventors have proposed a toner containing a binder resin, a charge control resin, a colorant and an external additive, wherein the charge control resin is represented by the formula (I):

[0006]

[Chemical 4]

60 to 97% by weight of a monomer represented by the formula (wherein R ¹ represents a hydrogen atom or a methyl group), represented by the formula (II):

[0008]

[Chemical 5]

(In the formula, R ² is a hydrogen atom or a methyl group, and R ² is
³ represents an alkyl group having 1 to 6 carbon atoms) and 1 to 33% by weight of a monomer represented by the formula (III):

[0010]

[Chemical 6]

(In the formula, R ⁴ is a hydrogen atom or a methyl group, and R ⁴ is
⁵ and R ⁶ represent an alkyl group having 1 to 4 carbon atoms) or a monomer mixture containing 2 to 35% by weight of a quaternary compound thereof. Fourth
The present invention relates to a toner containing a copolymer containing a primary ammonium base and containing negatively chargeable organic fine particles as an external additive.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a positively chargeable toner containing a binder resin, a charge adjusting resin, a colorant and an external additive, and a positively chargeable charge adjusting resin and a negative charge as the external additive. One feature is that the chargeable organic fine particles are used together.

In the present invention, the interaction between the positively chargeable specific charge adjusting resin and the negatively chargeable organic fine particles reduces the amount of the free negatively chargeable organic fine particles, which causes the toner to adhere to the developing blade and further to the toner surface. Efficient adhesion of the negatively chargeable organic fine particles prevents the toner from being fused to the developing roll, and a stable and good image can be obtained for a long period of time. Although details of obtaining such an effect are unknown, the compatibility of the specific charge adjusting resin and the binder resin and the characteristics of the charge adjusting resin as a resin make it possible to bind the charge adjusting resin to the binder during the production of the toner. It is presumed that the particles are easily crushed at the interface with the resin and the negatively chargeable organic fine particles are efficiently attached to the positively chargeable charge adjusting resin on the toner surface.

In the present invention, examples of the binder resin include polyesters, styrene-acrylic resins, epoxy resins, polycarbonates, polyurethanes and composites thereof, among which the effect of the present invention is easily exhibited. Therefore, polyester is preferable. The content of the polyester in the binder resin is preferably 50 to 100% by weight, more preferably 90 to 100% by weight, and particularly preferably 100% by weight.

The polyester is obtained by polycondensing a known alcohol component and a carboxylic acid component.

As the alcohol component, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.0) -2,
Alkylene oxide adducts of bisphenol A such as 2-bis (4-hydroxyphenyl) propane, alkylene (carbon number 2 to 3) oxides (average addition mole number 1 to 16), ethylene glycol, propylene glycol , Glycerin, pentaerythritol, trimethyloglycolpropane, hydrogenated bisphenol A, sorbitol, or their alkylene (C2-4) oxides (average added moles 1-1)
6) Additives and the like can be mentioned, which can be used alone or in admixture of two or more.

As the carboxylic acid component, dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, fumaric acid and maleic acid, alkyl groups having 1 to 20 carbon atoms such as dodecenyl succinic acid and octyl succinic acid, or 2 carbon atoms. ~
Examples include succinic acid, trimellitic acid, pyromellitic acid, anhydrides of those acids, and alkyl (C1 to C3) esters of these acids substituted with 20 alkenyl groups, which may be used alone or in combination with 2 A mixture of two or more species can be used.

The polyester can be produced, for example, by polycondensing an alcohol component and a carboxylic acid component in an inert gas atmosphere at a temperature of 180 to 250 ° C., if necessary using an esterification catalyst. it can.

The acid value of the polyester is 1 to 15 mgKO in order to use the toner of the present invention as a positively chargeable toner.
H / g is preferable and 3 to 10 mgKOH / g is more preferable. The hydroxyl value is preferably 20 to 80 mgKOH / g, the softening point is 100 to 160 ° C., and the glass transition point is 5.
It is preferably 0 to 70 ° C., respectively.

In the present invention, the charge control resin for imparting positive chargeability to the toner is represented by the formula (I):

[0021]

[Chemical 7]

(Wherein R ¹ represents a hydrogen atom or a methyl group), a monomer of the formula (II):

[0023]

[Chemical 8]

(In the formula, R ² is a hydrogen atom or a methyl group, and R ² is
³ represents an alkyl group having 1 to 6 carbon atoms) and a monomer represented by the formula (III):

[0025]

[Chemical 9]

(In the formula, R ⁴ is a hydrogen atom or a methyl group, and R ⁴ is
⁵ and R ⁶ represent an alkyl group having 1 to 4 carbon atoms) or a quaternary compound thereof, preferably a monomer mixture containing a monomer represented by the formula (III) A quaternary ammonium salt group-containing copolymer obtained by a step including a polymerization step is used.

The quaternary ammonium salt group-containing copolymer has a high positive chargeability, and even if the negatively chargeable polyester is contained as the binder resin, an excellent positive chargeability is obtained. A toner having a charging property can be obtained.

The monomer represented by the formula (I) includes R ¹
Wherein styrene is a hydrogen atom, and the monomer represented by the formula (II) is a monomer in which R ² is a hydrogen atom and R ³ is an alkyl group having 1 to 4 carbon atoms, preferably R ² is Hydrogen atom, R
^As butyl acrylate in which ³ is a butyl group, as the monomer represented by the formula (III), a monomer in which R ⁴ is a methyl group and R ⁵ and R ⁶ are a methyl group or an ethyl group, preferably,
Dimethylaminoethyl methacrylate in which R ⁴ , R ⁵ and R ⁶ are methyl groups is preferable.

The content of the monomer represented by the formula (I) in the monomer mixture is 60 to 97% by weight, preferably 70 to 9%.
0% by weight, the content of the monomer represented by the formula (II) is 1 to 33% by weight, preferably 5 to 20% by weight, the monomer represented by the formula (III) or The content of the quaternary compound is 2-35% by weight, preferably 5-20% by weight.

Polymerization of the monomer mixture is carried out, for example, by heating the monomer mixture to 50 to 100 ° C. in an inert gas atmosphere in the presence of a polymerization initiator such as azobisdimethylvaleronitrile. You can The polymerization method may be any of solution polymerization, suspension polymerization and bulk polymerization, but solution polymerization is preferred.

Examples of the solvent include organic solvents such as toluene, xylene, dioxane, ethylene glycol monomethyl ether, ethyl acetate and methyl ethyl ketone, and mixed solvents of these with lower alcohols such as methanol, ethanol, propanol and isopropanol.

In the present invention, when the monomer represented by the formula (III) is used, the copolymer thus obtained is further quaternized with a quaternizing agent.
The quaternary ammonium salt group-containing copolymer can be obtained. Examples of the quaternizing agent include methyl p-toluenesulfonate, dimethylsulfate, methyl hydroxynaphthalenesulfonate, methyl chloride, methyl iodide, and benzyl chloride. Among these, stable and high chargeability can be obtained. Methyl p-toluenesulfonate is preferred. The amount of the quaternizing agent used is preferably 0.8 to 1.0 mol with respect to 1 mol of the monomer represented by the formula (III). The quaternization of the copolymer can be carried out, for example, by heating the copolymer and the quaternizing agent in a solvent at 60 to 90 ° C.

When a quaternized product of the monomer represented by the formula (III) is used, the monomer represented by the formula (III) is quaternized by using the same quaternizing agent as described above. What was made into can be used. In addition, for example, a quaternary ammonium halide obtained by treating with an alkyl halide such as methyl chloride is used as a quaternary compound of the monomer represented by the formula (III),
The resulting copolymer can be treated with an acid such as p-toluenesulfonic acid or hydroxynaphthalenesulfonic acid to carry out counterion exchange to obtain the desired quaternary ammonium salt group-containing copolymer.

The weight average molecular weight of the quaternary ammonium salt group-containing copolymer thus obtained is 5,000 or more from the viewpoint of storage stability, and 100,000 or less from the viewpoint of compatibility with the resin. Preferably, more preferably 1
It is 50,000 to 50,000.

The content of the quaternary ammonium salt group-containing copolymer is preferably 0.5 to 40 parts by weight, more preferably 1 to 100 parts by weight of the binder resin in order to obtain an appropriate amount of charge. -30 parts by weight, particularly preferably 5-25 parts by weight.

As the colorant, all the dyes and pigments used as the colorant for toner can be used. Carbon black, phthalocyanine blue, permanent brown FG, brilliant fast scarlet, pigment green B, rhodamine- B base, Solvent Red 49, Solvent Red 146, Solvent Blue 35, Quinacridone, Carmine 6B, Disazo Yellow, and the like. These can be used alone or in combination of two or more, and in the present invention, the toner is black. It may be toner, color toner, or full-color toner. The content of the colorant is preferably 1 to 40 parts by weight, more preferably 3 to 10 parts by weight, based on 100 parts by weight of the binder resin.

Further, in the toner of the present invention, a charge control agent, a release agent, a conductivity adjusting agent, an extender pigment, a reinforcing filler such as a fibrous substance, an antioxidant, an antiaging agent, a fluidity improving agent,
An additive such as a cleaning property improver may be appropriately contained.

In the present invention, the negatively chargeable organic fine particles contained as an external additive are organic fine particles exhibiting negative chargeability by a two-component blow-off measurement method, and specifically,
Polytetrafluoroethylene (hereinafter referred to as PTFE)
Fluorine-containing resin such as, obtained by using an anionic initiator that generates anionic functional groups such as sulfonic acid groups, methyl methacrylate polymer, styrene polymer, methyl methacrylate-styrene copolymer, Examples thereof include a methyl methacrylate-acrylic acid ester copolymer, and among these, a fluorine-containing resin is preferable, and PTFE is more preferable, from the viewpoints of high chargeability and low friction.

The number average particle size of the organic fine particles is preferably 0.05 to 1.0 μm, in order to enhance the interaction with the specific charge adjusting resin and reduce the toner fusion, etc.
5 μm is more preferable. Here, the number average particle diameter of the organic fine particles is calculated by number-averaging the particle diameters of the primary particles measured from an electron micrograph.

Suitable PTFE in the present invention is as follows:
Particles having a shape close to a sphere produced by emulsion polymerization are preferred. As such a commercially available product, "KTL-5
00F "(Kitamura Co., Ltd., number average particle size 0.3 µm)," Lubron L2 "(Daikin Industries Co., Ltd., number average particle size 0.3 µm)
m), “Lubron L5” (manufactured by Daikin Industries, Ltd., number average particle size 0.2 μm), “Fluon Lubricant L170
J "(manufactured by Asahi IC Fluoropolymers Co., Ltd., number average particle size 0.1 μm)," Fluon Lubricant L172
"J" (manufactured by Asahi IC Fluoropolymers, number average particle size 0.1 µm), "MP-1100" (manufactured by Mitsui DuPont Fluorochemicals, number average particle size 0.2 µm), "MP"
-1200 "(manufactured by Mitsui DuPont Fluorochemicals, number average particle size 0.3 μm),“ TLP-10F-1 ”(manufactured by Mitsui DuPont Fluorochemicals, number average particle size 0.2 μm)
m) and the like.

The content of the negatively chargeable organic fine particles is 10 before the treatment with the external additive (hereinafter referred to as untreated toner).
It is preferably 0.01 to 2.5 parts by weight, more preferably 0.05 to 1.0 parts by weight, and particularly preferably 0.1 to 0.5 parts by weight, relative to 0 parts by weight.

In the present invention, from the viewpoint of fluidity, it is preferable that inorganic fine particles are further contained as an external additive. Examples of the inorganic fine particles include inorganic fine particles such as silica, alumina, titania, zirconia, tin oxide, and zinc oxide. Among them, silica having a small specific gravity is preferable from the viewpoint of preventing embedding.

From the viewpoint of environmental stability, the silica is preferably hydrophobic silica which has been subjected to a hydrophobizing treatment. The method of hydrophobizing is not particularly limited, and examples of the hydrophobizing agent include hexamethyldisilazane, dimethyldichlorosilane, silicone oil, and methyltriethoxysilane. Among these, hexamethyldisilazane is preferable. The treatment amount of the hydrophobic treatment agent is preferably 1 to 7 mg / m ² per surface area of the inorganic fine particles.

The average particle size of silica is preferably 5 to 100 nm, more preferably 10 to 50 nm.

The content of silica is preferably 0.01 to 10 parts by weight, based on 100 parts by weight of the untreated toner, and is 0.1.
1 to 5 parts by weight is more preferable.

The coverage of the toner with the negatively chargeable organic fine particles and the inorganic fine particles is preferably 50% or more, more preferably 60 to 100%, particularly preferably 70 to 90% in order to reduce the load directly applied to the toner surface. preferable. Here, the coverage refers to the ratio of the projected area of the external additive to the toner surface area.

The toner of the present invention is obtained by mixing an untreated toner containing a binder resin, a charge adjusting resin, a colorant and the like with an external additive.

The untreated toner is preferably crushed toner,
For example, a binder resin, a charge control resin, a colorant and the like are uniformly mixed with a mixer such as a Henschel mixer or a ball mill, and then melt-kneaded with a closed kneader or a uniaxial or biaxial extruder, and after cooling, Coarsely crush with a hammer mill,
Further, it is obtained by finely pulverizing with a fine pulverizer using a jet stream or a mechanical pulverizer, and classifying to a predetermined particle size with a classifier. The volume average particle diameter of the untreated toner is preferably 3 to 15 μm.

The mixing of the untreated toner and the external additive is not particularly limited as long as the external additive is attached to the surface of the toner particles, and examples thereof include mixing with a Henschel mixer, a micro speed mixer and a super mixer. Known methods can be mentioned.

The acid value of the toner of the present invention is preferably from 1 to 15 mgKOH / g from the viewpoint of charging stability, and from 3 to 10
More preferred is mgKOH / g.

The toner of the present invention having an excellent charging property is suitably used as a positively charging toner for non-magnetic one-component development. In addition, since the load on the toner on the developing roll can be reduced, the rotation direction of the photoconductor and the developing roll is the same, and the contact portion moves in the opposite direction. Can also be preferably used. It can also be suitably used for an electrophotographic apparatus of the age development type.

[0052]

[Example] [Acid value] Measured by the method of JIS K0070.

[Glass Transition Point] Differential Scanning Calorimeter “DSC
210 "(manufactured by Seiko Instruments Inc.)
Measure at 0 ° C / min.

Resin Production Example 1 Propylene oxide adduct of bisphenol A (2.
(2 mol) 10845 g, ethylene oxide adduct of bisphenol A (2.0 mol) 21125 g, terephthalic acid 14940 g and dibutyltin oxide 15 g were stirred at 230 ° C. under a nitrogen atmosphere to give a softening point measured according to ASTM D36-86. The reaction was carried out until the temperature reached 120 ° C., and Resin A was obtained. The resin A had a glass transition point of 63 ° C. and an acid value of 8.2 mgKOH / g.

Resin Production Example 2 Propylene oxide adduct of bisphenol A (2.
2mol) 9440 g, ethylene oxide adduct of bisphenol A (2.0 mol) 21125 g, terephthalic acid 14940 g and dibutyltin oxide 15 g were stirred at 230 ° C. under a nitrogen atmosphere, and the softening point measured according to ASTM D36-86 was measured. React until it reaches 120 ° C,
Resin B was obtained. Resin B had a glass transition point of 61 ° C. and an acid value of 13.1 mgKOH / g.

Production Example 1 of Charge Control Resin 250 g of methanol, 200 g of toluene, 50 of styrene
A mixture of 0 g, 40 g of butyl acrylate, 60 g of dimethylaminoethyl methacrylate and 12 g of azobisdimethylvaleronitrile was polymerized at 70 ° C. for 10 hours in a nitrogen atmosphere, and the obtained reaction solution was cooled and toluene 150 was added.
g, 100 g of ethanol and 71.0 g of methyl p-toluenesulfonate were added, and the mixture was stirred at 70 ° C. for 5 hours for quaternization. The reaction solution was heated to 100 ° C., the solvent was distilled off under reduced pressure, and the mixture was pulverized with a jet mill to obtain the charge control resin A.
(Weight average molecular weight: 14000) was obtained.

Production Example 2 of charge control resin 300 g of methanol, 100 g of toluene, 54 of styrene
0 g, a mixture of 60 g of dimethylaminoethyl methacrylate and 12 g of azobisdimethylvaleronitrile,
In the same manner as in Production Example 1 of charge adjusting resin, charge adjusting resin B
(Weight average molecular weight: 3500) was obtained.

[0058] Example 1 Resin A 100 parts by weight Charge adjusting resin A 10 parts by weight Carbon black 4 parts by weight   "REGAL-330R" (made by Cabot) Charge control agent (Nigrosine dye) 4 parts by weight   "Bontron N-04" (manufactured by Orient Chemical Industry Co., Ltd.) Low molecular weight polypropylene wax 2 parts by weight   "High Wax NP-055" (Mitsui Petrochemical Co., Ltd.)

After mixing the above raw materials using a Henschel mixer, melt kneading with a twin-screw extruder, crushing with a collision plate crusher, classification with a classifier "dispersion separator" (manufactured by Nippon Pneumatic Industry Co., Ltd.) After that, an untreated toner having a volume average particle diameter of 9.5 μm and a coefficient of variation of 22.3% was obtained.

To 100 parts by weight of the obtained untreated toner, PTFE particles "KTL-500F" (manufactured by Kitamura Co., number average particle size: 0.3 μm, charge amount: -27 μC) were added as an external additive.
/ G) 0.3 parts by weight and hydrophobic silica "TS-720"
(Wacker Chemical Co., average particle size: 12 nm) 0.5
5 parts by weight was added and mixed with a Henschel mixer to obtain a toner. The acid value of the obtained toner is 8.1 mgKOH /
The toner coverage with the external additive was 74%.

Example 2 As an external additive, instead of the PTFE particles, methyl methacrylate-styrene copolymer fine particles "NK-32" (manufactured by Nippon Paint Co., Ltd., number average particle size: 80 nm, charge amount: -5 μC)
/ G) A toner was obtained in the same manner as in Example 1 except that 0.3 part by weight was used. The toner coverage with external additives is 8
It was 3%.

Example 3 A toner was obtained in the same manner as in Example 1 except that the amount of hydrophobic silica used was changed to 0.4 part by weight. The toner coverage with the external additive was 54%.

Example 4 The same as Example 1 except that 100 parts by weight of Resin B was used in place of Resin A, and the volume average particle size was 9.6 μm.
An untreated toner having a coefficient of variation of 24.3% was obtained and further mixed with an external additive to obtain a toner. The acid value of the obtained toner is 1
The coverage of the toner with 2.8 mg KOH / g and the external additive was 75%.

Comparative Example 1 The same procedure as in Example 1 was carried out except that 10 parts by weight of the charge control resin B was used in place of the charge control resin A, and the untreated sample having a volume average particle size of 9.6 μm and a coefficient of variation of 24.3%. Get toner,
Further, it was mixed with an external additive to obtain a toner. The acid value of the obtained toner was 8.1 mgKOH / g, and the coverage of the external additive on the toner was 75%.

Comparative Example 2 A toner was obtained in the same manner as in Example 1 except that the charge control resin A was not used. The acid value of the obtained toner is 8.1.
mgKOH / g, toner coverage with external additives is 75%
Met.

Comparative Example 3 A toner was obtained in the same manner as in Example 1 except that the PTFE particles were not used. The acid value of the obtained toner is 8.1 m.
The coverage of the toner with gKOH / g and the external additive was 73%.

Comparative Example 4 A toner was obtained in the same manner as in Example 1 except that the charge control resin A and PTFE particles were not used. The acid value of the obtained toner was 8.1 mgKOH / g, and the coverage of the toner with the external additive was 73%.

Test Example 1 Non-magnetic one-component developing device "HL-104 by reversal development"
0 "(made by Brother Industries, Ltd.) with toner mounted, printing rate 5
%, 10000 sheets of durable printing were performed, and then the deposits on the developing blade were visually observed and evaluated according to the following evaluation criteria. The results are shown in Table 1.

[Evaluation Criteria] ⊚: No adhering matter is observed, which is particularly good in actual use. ◯: There is a slight adhered substance, but no streak is observed on the image, and there is no problem in actual use. Δ: There are slight deposits and slight streaks are observed on the image, which may cause a problem in actual use. X: There is an adhered substance, and streaks are generated on the image, so that actual use is impossible.

Test Example 2 Using the same apparatus as in Test Example 1, 10000 sheets of durable printing were performed, and then the fusion on the developing roll was visually observed and evaluated according to the following evaluation criteria. The results are shown in Table 1.

[Evaluation Criteria] ⊚: No fusion is observed, which is particularly good in actual use. ◯: Fusing is slightly recognized, but there is no particular problem in the image and no problem in actual use. X: Fusing occurs and unevenness occurs on the image, so that actual use is impossible.

[0072]

[Table 1]

From the above results, it is understood that the toners of Examples 1 to 4 can continuously obtain excellent images without causing the adhered matter on the developing blade or the toner fusion on the developing roll. In contrast, the toner of Comparative Example 1 containing the charge control resin obtained without using the monomer represented by the formula (II) and the toner of Comparative Example 2 obtained without using the charge control resin were , Because the adhesion of the PTFE particles to the toner is weak,
In both cases, toner fusion to the developing roll occurs. In the toner of Comparative Example 1, the reason why the adhesive force of the PTFE particles is weakened is presumed to be because the dispersed domain diameter of the charge control resin in the toner becomes large. Further, in the toner of Comparative Example 3 obtained without using the PTFE particles, the charge adjusting resin on the toner surface adheres to the developing blade, and the charge adjusting resin and PTF are removed.
In Comparative Example 4 in which none of the E particles was used, an adhered substance was generated on the developing blade and the toner was fused to the developing roll.

[0074]

According to the present invention, even in a non-magnetic one-component developing system, a positive charging having excellent durability can be achieved without causing deposits on the developing blade and toner fusion on the developing roll.
It is possible to provide sexual toner.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuhiro Hidaka             1334 Minato Minato, Wakayama Kao Corporation             Within F-term (reference) 2H005 AA01 AA06 AA08 CA04 CA08                       CA11 DA03 EA07 EA10 FA07                 2H077 AD02 AD06 BA03 EA00 EA14                       EA15 GA03 GA17

Claims (6)

[Claims] 1. A toner comprising a binder resin, a charge control resin, a colorant and an external additive, wherein the charge control resin is represented by the formula (I): (Wherein R ¹ represents a hydrogen atom or a methyl group) in an amount of 60 to 97% by weight, represented by the formula (II): (In the formula, R ² is a hydrogen atom or a methyl group, and R ³ is a carbon atom 1
1 to 33 represent a monomer represented by
% By Weight and Formula (III): (Wherein R ⁴ represents a hydrogen atom or a methyl group, R ⁵ and R ⁶ represent an alkyl group having 1 to 4 carbon atoms) or a quaternary compound thereof is contained in an amount of 2 to 35% by weight. A toner comprising a quaternary ammonium salt group-containing copolymer obtained by a step including a step of polymerizing a monomer mixture, and negatively chargeable organic fine particles as an external additive. 2. The content of the quaternary ammonium salt group-containing copolymer is 0.5 to 40 with respect to 100 parts by weight of the binder resin.
The content of the negatively chargeable organic fine particles is 0.01 to 100 parts by weight of the toner before the treatment with the external additive.
The toner according to claim 1, which is 2.5 parts by weight. 3. The toner according to claim 1, which is a positively chargeable toner for non-magnetic one-component development. 4. The binder resin has an acid value of 10 mgKOH / g.
The toner according to claim 1, which comprises the following polyester. 5. The toner according to claim 1, wherein the negatively chargeable organic fine particles are polytetrafluoroethylene. 6. The toner according to any one of claims 1 to 5, which is used for an electrophotographic apparatus of an age development type in which a photoconductor and a developing roll rotate in the same direction.