JP2002023425A - Nonmagnetic single component developer and method for development by using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonmagnetic single component developer which can form an excellent image. SOLUTION: The nonmagnetic single component developer contains a partial potassium salt of an aromatic compound expressed by formula (1) or (2) as an electrification controlling agent, and the ratio of the volume average particle diameter (Dv50) to the number average particle diameter (Dn50) satisfies 1.0<=Dv50/Dn50<=1.2. In formulae, each of A1 to A3 and R1 to R3 represents an aromatic ring which may have substituents, -OH and -CONHR are bonded to the sites adjacent to each other and n is a positive integer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-magnetic one-component developer used in an electrophotographic copying machine or printer, and a developing method using the same.

[0002]

2. Description of the Related Art As is well known, a two-component developer composed of a toner and a carrier is mainly used in an electrophotographic copying machine or a printer. However, the apparatus can be reduced in size and maintenance is easy. It is considered advantageous to use a one-component developer. The one-component developer includes a magnetic one-component developer containing a magnetic powder and a non-magnetic one-component developer without a magnetic powder. After development, it is difficult to transfer this to paper or the like, and since it contains a large amount of magnetic powder, colorization is impossible. On the other hand, the latter has a large specific resistance, is easy to transfer a toner image to paper or the like, and is easy to colorize.

In a typical developing device using a non-magnetic one-component developer, a developing roll and a toner replenishing roll are mounted in a container installed near a photoreceptor, and a voltage is applied to the developing roll from a power source. ing. When a one-component developer composed of non-magnetic toner is supplied to this container and the toner supply roll is rotated, the toner is transported onto the development roll.
The toner on the developing roll is conveyed onto the photoconductor by rotation of the developing roll, and develops the electrostatic latent image formed on the photoconductor. In this developing method, it is necessary to form a thin toner layer with a uniform thickness on the developing roll,
Therefore, the thickness of the toner layer formed on the developing roll is
A blade is provided as a regulating member for making the thickness uniform and thin.

[0004]

However, when a conventional toner for a two-component developer is used as a developer in this developing method, it is difficult to form a uniform and thin toner layer on a developing roll. Extremely difficult. As a result, there is a problem that only a poor image having a low image density and a lot of fog can be obtained. Accordingly, an object of the present invention is to provide a non-magnetic one-component developer free from such a problem.

[0005]

According to the present invention, there is provided a non-magnetic one-component developer in which an electrostatic latent image formed on a photoreceptor is provided with a regulating member for making the thickness of a developer layer uniform. Used in a developing method of supplying a developer through a developing roll provided, wherein at least a binder resin, a colorant, and a partial potassium salt of a compound represented by the general formula (1) or (2) are selected. And the ratio of the number average particle diameter (D _n 50) to the volume average particle diameter (D _v 50) is 1.0.
It is characterized in that a _{≦ D v 50 / D n 50} ≦ 1.2.

[0006]

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(A ¹ and R ¹ each independently represent an optionally substituted aromatic ring. —OH and —CO
NH-R ¹ is bonded to an adjacent position on ring A ¹ . )

[0008]

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[0009] (A ^2, A ^3, R ² and R ³ are each independently have a substituent represents an even aromatic ring, n represents represents a positive integer .A on ² rings the -OH and -CONH-R ² and a ³ -OH and -CONH-R ³ on the ring, is bonded to a position adjacent on each ring.)

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The non-magnetic one-component developer according to the present invention is essentially composed of a binder resin, a colorant and a charge control agent. Various binder resins known to be usable as binder resins for toner can be used as the binder resin. For example, styrene resin, vinyl chloride resin, rosin-modified maleic resin, phenol resin, epoxy resin, saturated or unsaturated polyester resin, ionomer resin, polyurethane resin, silicone resin, ketone resin, ethylene-ethyl acrylate copolymer , Xylene resin, polyvinyl butyral resin, and the like. Among them, it is preferable to use a styrene resin, a saturated or unsaturated polyester resin, an epoxy resin, or the like. These resins are usually used alone, but some may be used in combination. In addition, these resins can be used as a non-crosslinked or crosslinked resin or as a mixture of a crosslinked resin and a noncrosslinked resin according to the fixing method of the toner.

As the styrene resin, polystyrene,
Polychlorostyrene, poly-α-methylstyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-
Vinyl chloride copolymer, styrene-vinyl acetate copolymer,
Styrene-maleic acid copolymer, styrene-acrylate copolymer (styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-
Butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-phenyl acrylate copolymer, etc.), styrene-methacrylate copolymer (styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate) Copolymer, styrene-butyl methacrylate copolymer, styrene-octyl methacrylate copolymer, styrene-phenyl methacrylate copolymer), styrene-α-methyl methyl acrylate copolymer, and styrene-acrylonitrile-acryl And acid ester copolymers. These styrene resins can be used as a crosslinked resin by copolymerizing a crosslinkable component. There are various methods for producing a styrene resin, such as bulk polymerization, suspension polymerization, solution polymerization, and emulsion polymerization, and any of these production methods can be used.

The polyester resin is mainly composed of a divalent carboxylic acid and a dihydric alcohol, and if desired, a mixture of a small amount of a trivalent or more carboxylic acid and an alcohol is polycondensed. What is necessary is just to select and use suitably from well-known resins as a resin. Examples of the divalent carboxylic acid include isophthalic acid, terephthalic acid, adipic acid, sebacic acid, diphenic acid, naphthalenedicarboxylic acid, and cyclohexanedicarboxylic acid. 2
Examples of the divalent alcohol include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol,
1,4-butanediol, neopentyl glycol,
Chain diols such as 1,4-butenediol, aromatic diols such as bisphenol A, etherified aromatic diols such as polyoxyethylenated bisphenol A, polyoxypropylene bisphenol A and the like are used. Examples of trivalent or higher carboxylic acids and alcohols include trimellitic acid, cyclohexanetricarboxylic acid, naphthalenetricarboxylic acid, butanetricarboxylic acid, hexanetricarboxylic acid, octanetetracarboxylic acid, trimethylolethane, trimethylolpropane, glycerin, and pentaerythritol. Used. Note that carboxylic acids can also be used as reactive derivatives such as acid anhydrides and lower alkyl esters.

The molecular weight and molecular weight distribution of the binder resin are appropriately selected according to the characteristics of the developing device and the fixing system. Preferably, as the binder resin, the storage elastic modulus G ′ of _1% at a strain of _1% and the storage elastic modulus G ′ of _{30% at a} strain of 30% in the dynamic viscoelasticity measurement are in the following ranges. Use something.

[0014]

1.0 × 10 ² (Pa) ≦ G ′ _1% ≦ 1.0 × 1
^{0 4 (Pa) 1.0 ≦ G} '30% / G' 1% ≦ 10.0

However, the dynamic viscoelasticity was measured by UBM Co., Ltd.
It is performed at a frequency of 1 Hz with a parallel plate using MR-500 manufactured by Toshiba Corporation. The measurement temperature is 150 ° C. for a single color toner and 120 ° C. for a full color toner. As a coloring agent, carbon black,
Ultramarine, nigrosine dye, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa Yellow G, rhodamine dye, chrome yellow, quinacridone, benzidine yellow, rose bengal, triallylmethane dye, monoazo dye, disazo dye, condensed azo dye What is necessary is just to select and use suitably from what is known as a coloring agent of a toner, such as a pigment. If desired, some coloring agents may be used in combination. In the case of a full-color toner, benzidine yellow, monoazo dyes, condensed azo dyes and the like for yellow toner, quinacridone, rhodamine dyes and monoazo dyes for magenta toner, phthalocyanine blue for cyan toner, It is preferable to use carbon black for each of the black toners. The colorant is used usually in an amount of 1 to 20 parts by weight based on 100 parts by weight of the binder resin.

In the present invention, a partial potassium salt of an aromatic compound represented by the general formula (1) or (2) is contained in the toner as a charge control agent. Its content is 10
It is usually 0.1 to 20 parts by weight per 0 parts by weight. If the content is too small, the effect of improving the chargeability is not sufficiently exhibited,
Conversely, if the content is too large, the quality of the toner deteriorates. The preferred content of the partial potassium salt is 0.1 to 15 parts by weight, particularly 0.5 to 7 parts by weight, per 100 parts by weight of the binder resin.

[0017]

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(A ¹ and R ¹ each independently represent an optionally substituted aromatic ring. —OH and —CONH
-R ¹ and is attached to a position adjacent on the ring A ^1. )

[0019]

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[0020] (A ^2, A ^3, R ² and R ³ are each independently have a substituent represents an even aromatic ring, n represents represents a positive integer .A on ² rings the -OH and -CONH-R ² and a ³ -OH and -CONH-R ³ on the ring, is bonded to a position adjacent on each ring.)

In the general formulas (1) and (2), A ¹ to
The aromatic ring represented by A ³ and R ^{1 to} R ³ includes a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a carbazole ring, a fluorene ring, a fluorenone ring,
Examples include a dibenzofuran ring and a dibenzothiophene ring. Substituents bonded to these aromatic rings include methyl, ethyl, n-propyl, n-butyl, t-
-A lower alkyl group or a lower alkoxy group having 1 to 5 carbon atoms which may be substituted with a halogen atom, such as a butyl group, a trifluoromethyl group, a methoxy group, an ethoxy group; a halogen atom such as a chlorine atom or a bromine atom; Group, phenyl group and the like. Preferably, A ^{1 to} A ³ and R ¹ to
The aromatic ring represented by R ³ is a benzene ring or a naphthalene ring, and the substituent bonded to these aromatic rings is a lower alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom. It is a lower alkoxy group or a halogen atom.
In the general formula (2), n is usually 1 to 5,
It is preferably 1-3. Among the aromatic compounds represented by the general formula (1), those represented by the general formula (3) are preferred.

[0022]

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(A ⁴ represents a benzene ring or a naphthalene ring to which one or two lower alkyl groups having 1 to 5 carbon atoms may be bonded, and R ⁴ represents a carbon atom which may be substituted by a halogen atom. Represents a benzene ring or a naphthalene ring to which one or two substituents selected from the group consisting of 1 to 5 lower alkyl groups and halogen atoms may be bonded.) Aroma represented by the general formula (3) Some of the group III compounds are shown in Table 1.

[0024]

[Table 1]

Among the aromatic compounds represented by the general formula (2), those represented by the general formula (4) are preferred.

[0026]

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(A ⁵ and A ⁶ each represent a naphthalene ring; R ⁵ and R ⁶ each independently represent a lower alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom; Represents a benzene ring or a naphthalene ring to which one or two substituents selected from the group consisting of may be bonded.) Some of the aromatic compounds represented by the general formula (4) are represented by the following formula:
It is shown in FIG.

[0028]

[Table 2]

The naphthalene ring represented by A ⁵ and A ⁶
In in any of the naphthalene rings represented also, -CH ₂
-Is bonded to the 1-position, -OH is bonded to the 2-position, and -CONHR is bonded to the 3-position. The partial potassium salt which is a charge controlling agent used in the present invention is a compound in which potassium is bonded to an aromatic compound represented by the general formula (1) or (2), and the potassium content of the aromatic compound is 1 Usually 0.0 per molecule
01 to 0.5 atom. If the content of potassium is more than this, the water resistance is undesirably deteriorated. Conversely, when the content of potassium is lower than this, the charging characteristics deteriorate. The preferable potassium content of the partial potassium salt is such that potassium is 0.001 to 1 molecule per aromatic compound.
0.3 atom, especially 0.001 to 0.1 atom. The aromatic compound may contain a cation other than potassium, but the amount thereof is preferably small. For example, sodium, which is a typical cation, has an atomic ratio of 0.5 or less with respect to potassium. It is preferred that The aromatic compound represented by the general formula (1) can be produced by reacting salicylic acid optionally having a substituent on a ring with an aromatic amine according to the following formula.

[0030]

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The reaction proceeds easily by adding salicylic acid and aromatic amine as raw materials in toluene or chlorobenzene, further adding phosphorus trichloride and heating. In order to convert the obtained aromatic compound into a partial potassium salt, the partial potassium salt may be crystallized by heating and dissolving in a water / acetone solution of potassium hydroxide, and then adding water to the solution. The aromatic compounds represented by the general formula (2) include Brass Somer and Berichte (Be)
r. ). 61, 998 (1928). For example, for the partial potassium salt of an aromatic compound represented by the general formula (4), a potassium salt or a sodium salt of an aromatic compound may be produced according to the following formula, and then converted to a partial alkali salt.

[0032]

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The reaction proceeds easily when a raw material hydroxynaphthalene carboxylic acid derivative is added to an aqueous solution of caustic soda or potassium hydroxide, formaldehyde is added thereto, and the mixture is heated to 50 to 120 ° C. When the product is a sodium salt, the product is dissolved in an organic solvent such as N-methylpyrrolidone, methanol, dimethylformamide, and methyl ethyl ketone, and the resulting solution is added to an aqueous solution of a potassium salt such as potassium carbonate and potassium chloride. To the partial potassium salt. Alternatively, the product may be washed with the above organic solvent containing a potassium salt.

When the product is a potassium salt, a solution of the product in an organic solvent may be added to water, or the product may be washed with an organic solvent and water. The same organic solvent as described above can be used. The product can also be converted to partial potassium salts by washing with hot water. Upon conversion to these partial potassium salts, usually 10 to 500 parts by weight of organic solvent and 1 part by weight of water per 100 parts by weight of the product
About 0 to 5000 parts by weight may be used. The potassium salt may be used in an amount of about 0.1 to 4 mol per 1 mol of the sodium salt.

The toner according to the present invention consists essentially of the binder resin, the colorant and the charge control agent described above, but may optionally contain other conventional auxiliaries. For example, the above-mentioned charge control agent may contain another charge control agent, for example, a nigrosine dye, a quaternary ammonium salt, a metal-containing complex compound, a boron-containing complex compound, or the like. The content is preferably 0.1 to 20 parts by weight, particularly preferably 0.1 to 10 parts by weight, per 100 parts by weight of the binder resin. Also, when a low melting point wax such as paraffin wax, ketone wax, rice wax, Fischer-Tropsch wax or the like having a melting point of 50 to 100 ° C. is contained in an amount of about 0.1 to 30 parts by weight with respect to 100 parts by weight of the binder resin, it is generally fixed. The performance is improved. The melting point of these low melting waxes is 60-90.
° C, and the half width of the endothermic peak corresponding to the melting point in DSC measurement is 20 ° C or less, particularly 10 ° C.
The narrower one is preferred as follows.

Other auxiliaries include polypropylene wax, polyethylene wax, modified polypropylene wax, modified polyethylene wax and the like, which are used in an amount of usually 0.1 to 30 parts by weight per 100 parts by weight of the binder resin. Can be Silicone oil, modified silicone oil, silicone varnish, modified silicone varnish, etc. are usually 0.01 parts by weight per 100 parts by weight of the binder resin.
It is used so as to be 20 parts by weight. The metal soap is used in an amount of 0.05 to 10 parts by weight per 100 parts by weight of the binder resin. Metal soap is sometimes used as an external additive.

The toner according to the present invention is blended with a binder resin, a colorant, an antistatic agent and other auxiliaries according to a conventional method, uniformly mixed, and then subjected to melt-kneading, pulverization and classification steps. Can be manufactured. For kneading, a sealed kneader or a single or twin screw extruder is used. The kneaded material is cooled and solidified, then coarsely pulverized with a crusher or hammer mill, etc.
Next, it is finely pulverized to a desired particle size by a jet mill, a high-speed rotor rotary mill, or the like. The pulverized material is classified by an inertial classification type elbow jet, a centrifugal force classification type microplex, a DS separator, or the like to obtain a particle having a desired particle size.

Usually, organic or inorganic fine particles are added to the above-obtained toner to improve the fluidity and adjust the chargeability to obtain a product toner. As the inorganic fine particles, titania,
Magnetite, ferrite, cerium oxide, strontium titanate, talc, talcites, silicon nitride, titanium nitride and the like are used. Among them, it is preferable to use silica, alumina, titania or the like. Particularly preferred is silica. The inorganic fine particles are preferably used after being treated with a hydrophobizing agent so that the degree of hydrophobicity by methanol titration is 50 or more, particularly 60 or more. Hydrophobicity of 50
By adding the above-mentioned inorganic fine particles, the charging characteristics of the blade are improved, and the amount of toner adhering to portions other than the electrostatic latent image on the photoreceptor is reduced, so that the transfer efficiency is improved. The addition amount of these inorganic fine particles is usually 0.1 to 5.0% by weight, preferably 0.1 to 3.0% by weight, based on the toner. As the organic fine particles, styrene resin, acrylic resin, benzoguanamine resin, melamine resin and the like are used. The addition amount is usually 0.0
5 to 10% by weight.

The toner according to the present invention has a particle size distribution
It is necessary that the ratio of the number average particle diameter (D _n 50) and a volume average particle diameter (D _v 50) is _{1.0 ≦ D v 50 / D n} 50 ≦ 1.2. If the ratio is out of this range, a sufficient amount of charge cannot be obtained, or the uniformity of charge is reduced, resulting in a decrease in transfer efficiency and fogging. D _n 50 and D _v 50 and the ratio _{1.0 ≦ D v 50 / D n} 50 ≦ 1.
A value of 15 is more preferable. The particle size distribution of the toner is D _n 5
0 / Ratio of D _v 50 is in addition to the above range, further the volume average particle diameter (D _v 50) is 4 to 10 [mu] m, particle size 5
The ratio of those having a particle size of 10 μm or less is 10% by number or more, and the particle size is 8 to 1.
It is more preferable that the ratio of those having a size of 2.7 μm is 40 number% or less and the ratio of those having a particle size of 16 μm or more is 2 volume% or less.

The toner according to the present invention preferably has a shape of Wardell's sphericity of from 0.4 to 1.0, particularly from 0.6 to 1.0, because the image quality is generally improved. In order to keep the Wardel's sphericity within this range, it is preferable to pulverize the melt-kneaded mixture in the toner production process under exothermic conditions at the expense of the pulverization efficiency. Further, a method in which mechanical or thermal energy is added to the pulverized product by a conventional method, such as mechanofusion or surffusion, can also be used. According to a so-called polymerization method such as suspension polymerization or emulsion polymerization, regardless of the pulverization method, a toner having a Wardel sphericity within the above range can be obtained more easily.

A developing device for supplying a developer to an electrostatic latent image formed on a photoreceptor through a developing roll provided with a regulating member for making the thickness of the developer layer uniform, When the non-magnetic one-component toner according to the present invention is used, a uniform thin toner layer is formed on the developing roll, and the charge on the particle surface is constant and uniform. And the transfer efficiency of the toner is increased. As a result, a clear image having a high image density can be stably obtained for a long period of time. The toner according to the present invention exerts its performance when used in any device as long as it is a device that supplies the toner via a developing roll provided with the above-described regulating member. When used in a reversal developing system in which the polarity of the image and the polarity of the developer are the same, the performance is sufficiently exhibited. Regarding the relationship between the photoreceptor and the developing roll, it is preferable to use a so-called contact developing method in which the two are brought into direct contact for development.

[0042]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. The particle size distribution and other measurements described in this specification are based on the following.

Measurement of particle size distribution of toner: Isoton electrolytic solution
To 30 ml of II, an appropriate amount (about 0.03 g) of an alkylbenzene sulfonate is added as a dispersant. 2 to 20 mg of a sample is added to the solution, and the mixture is subjected to a dispersion treatment with an ultrasonic disperser for 30 to 60 seconds. The particle size distribution of the obtained suspension is measured using a Coulter Counter Multisizer II (manufactured by Coulter Inc.). Based on this measurement result, the volume average particle diameter (D _v 50) assuming the shape and spherical shape, number average particle diameter (D _n 50) to calculate the other.

Wardel sphericity; Flow soap 230
BE0 by nitrogen adsorption method using Type 0 (manufactured by Shimadzu Corporation)
The T method specific surface area is measured. Separately, the specific surface area ( _Dv50 specific surface area) is calculated from the volume average particle diameter ( _Dv50 ) obtained by the above particle size distribution, and the degree of spherical shape of Wardel is calculated by the following equation.

[0045]

[Number 2] Wateru of sphericity = D _v 50 specific surface area / BET
Law specific surface area

Melting point: Using DSC 220U (manufactured by Shimadzu Corporation), the melting point was calculated from the intersection of the tangent line having the largest slope and the base line among the tangent lines on the low temperature side of the endothermic curve measured at a heating rate of 10 ° C./min. I do. Degree of hydrophobicity: 0.20 g (0.20 ± 0.01 g) of a sample is collected in a 100 ml beaker, and 50 ml of pure water is added thereto. Inject methanol below the liquid level while stirring with a magnetic stirrer. From the amount of methanol (ml) injected until no sample is observed on the liquid surface, the degree of hydrophobicity is calculated based on the following equation.

[0047]

## EQU3 ## Degree of hydrophobicity = amount of methanol × 100 / (50 + amount of methanol)

Example 1 Synthesis of a charge controlling agent (compound No. 2 in Table 2)
282 g of [N- (P-chlorophenyl) carbamoyl] -3-hydroxynaphthalene was added to methanol 400m
1, 113.4 g of sodium hydroxide and 1440 ml of water
Was dissolved in the mixture. This solution was heated to 80 ° C., and 66 g of a 35% aqueous formaldehyde solution was added thereto.
The reaction was performed at 9 ° C. for 9 hours. The reaction was cooled to 50 ° C., filtered to obtain a yellow solid and dried. The yield was 261 g. 120 g of this yellow solid was added to and dissolved in 167 ml of N-methylpyrrolidone, which was maintained at 60 ° C., and a solution of 27 g of potassium carbonate in 2400 ml of water was added thereto over 1 hour. Subsequently, the mixture was further kept at 60 ° C. for 1 hour and then filtered to obtain a precipitated pale yellow solid, which was dried. The yield was 110 g. The potassium content of this was determined according to NO. It was 0.03 atom per 1 compound molecule. Almost no sodium was detected.

Production of toner; crosslinked polyester resin 10
0 parts by weight, carbon black (MA-1 manufactured by Mitsubishi Chemical Corporation)
7) and 3 parts by weight of the charge control agent obtained above were mixed, and the mixture was melt-kneaded using a twin-screw extruder. After cooling, the kneaded material was coarsely pulverized by a hammer mill and then finely pulverized by a supersonic jet mill. Classify the particles with an air classifier to obtain a part having a particle size of 5 to 30 μm, and add 0.5 parts by weight of hydrophobic silica (product of Wacker Chemical Co., H-2000) and hydrophobic silica (product of Cabot Co., TS- 72
0) 0.4 parts by weight was attached using a Henschel mixer to obtain a toner. Number average particle size (D _n 50)
Was 8.6 μm, the volume average particle size (D _v 50) was 8.9 μm, and D _v 50 / D _n 50 was 1.035. 30.0% by number, particle diameter of 5 μm
The following were 12.1 number%, and those having a particle size of 16 μm or more were not substantially present.

Example 2 100 parts by weight of a cross-linked polyester resin, 8 parts by weight of a master batch (pigment concentration: 50% by weight) of the cross-linked polyester resin and phthalocyanine blue pigment, and 3 parts by weight of a charge control agent obtained in Example 1 After mixing, the mixture was melt-kneaded using a twin-screw extruder. The kneaded material was pulverized, classified, and added with hydrophobic silica in the same manner as in Example 1 to obtain a toner. Number average particle diameter D _n 50 of this product 8.0 .mu.m, the volume average particle diameter (D _v 50) is _{8.6μm, D v 50 / D n} 50
= 1.075. Those with a particle size of 8 to 12.7 μm were 24.3% by number, those with a particle size of 5 μm or less were 14 number%, and those with a particle size of 16 μm or more were not substantially present. The Wardel sphericity was 0.57.

Performance test of toner: An electronic device of a system in which a developing roll provided with a blade for making the thickness of a developer layer uniform and a photosensitive member are in contact with each other and the developer is supplied via the developing roll. The toner obtained above is supplied to a photographic copying machine, and 20,000 sheets are continuously copied by a reversal development method. Immediately after the start of copying and after 20,000 sheets are copied, transfer efficiency, image density of the obtained image, fog, The image quality was examined. As a result, all items were satisfactory, and 2000
It was confirmed that a stable image could be obtained in zero continuous copying.

Continued on the front page (72) Inventor Teruki Senokuchi 1 Fukudacho, Joetsu City, Niigata Prefecture Inside the Naoetsu Works, Mitsubishi Chemical Corporation (72) Inventor Masakazu Sugihara 1 Fukudacho, Joetsu City, Niigata Prefecture Naoetsu Business, Mitsubishi Chemical Corporation In-house F term (reference) 2H005 AA06 AA15 CB10 DA01 EA05 FA07 2H077 AD06 AD13 AD17 AD22 EA14 EA15 GA17

Claims (10)

[Claims] 1. A developing method for supplying a developer to an electrostatic latent image formed on a photoreceptor via a developing roll having a regulating member for making the thickness of the developer layer uniform. A non-magnetic one-component developer to be used, which contains at least a binder resin, a colorant, and a charge control agent selected from a partial potassium salt of an aromatic compound represented by the general formula (1) or (2). nonmagnetic cage, and the ratio of the number average particle diameter and (D _n 50) and a volume average particle diameter (D _v 50) is characterized in that it is a _{1.0 ≦ D v 50 / D n} 50 ≦ 1.2 One-component developer. Embedded image (A ¹ and R ¹ each independently represent an aromatic ring which may have a substituent. —OH and —CONH—R ¹ are bonded to adjacent positions on the ring A ¹ (2) ^{(A 2, A 3, R} 2 and R ³ each independently represents an aromatic ring optionally having a substituent, n represents an -OH on .A ² ring represents a positive integer the -CONH-R ² and a ³ -OH and -CONH-R ³ on the ring, is bonded to a position adjacent on each ring.) 2. An aromatic compound represented by the general formula (1) or (2), wherein A ¹ , A ² , A ³ , R ¹ , R ² and R
³ may each independently be substituted with a substituent selected from the group consisting of a lower alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom, a lower alkoxy group and a halogen atom, The non-magnetic component developer according to claim 1, wherein the non-component developer represents a benzene ring or a naphthalene ring. 3. The non-magnetic one component according to claim 1, wherein the aromatic compound represented by the general formula (1) or (2) is one represented by the general formula (3). Developer. Embedded image (A ⁴ represents a benzene ring or a naphthalene ring to which one or two lower alkyl groups having 1 to 5 carbon atoms may be bonded, and R ⁴ has 1 to 5 carbon atoms which may be substituted with a halogen atom. May have one or two substituents selected from the group consisting of a lower alkyl group and a halogen atom,
Represents a benzene ring or a naphthalene ring. ) 4. The non-magnetic monocomponent according to claim 1, wherein the aromatic compound represented by the general formula (1) or (2) is a compound represented by the general formula (4). Developer. Embedded image (A ⁵ and A ⁶ each represent a naphthalene ring; R ⁵ and R ⁶ each independently represent a lower alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom; Represents a benzene ring or a naphthalene ring in which one or two substituents selected from may be bonded.) 5. The partial potassium salt of an aromatic compound contains 0.001 to 0.5 atom of potassium per molecule of the aromatic compound. Non-magnetic one-component developer. 6. A volume average particle diameter (D _v 50) of 4 to 10 μm.
m, the ratio of particles having a particle diameter of 5 μm or less is 10% by number or more, the ratio of particles having a particle diameter of 8 to 12.7 μm is 40% by number or less, and the ratio of particles having a particle diameter of 16 μm or more is 2% by volume or less. The non-magnetic one-component developer according to any one of claims 1 to 5, characterized in that: 7. The non-magnetic one-component developer according to claim 1, wherein the spherical degree of Wardell is 0.4 to 1.0. 8. An electrostatic latent image formed on a photoreceptor is developed by using a developing device provided with a developing roller and a regulating member for making the thickness of the developer layer on the developing roll uniform. 8. A method for developing by using the developer according to claim 1. 9. The developing method according to claim 8, wherein the developing is performed by a reversal developing method in which the polarity of the electrostatic latent image formed on the photosensitive member and the polarity of the developer are the same. 10. The developing method according to claim 8, wherein the electrostatic latent image formed on the photoconductor is developed by bringing the photoconductor into contact with a developing roll.