JP2002258501A - One-component developer and image forming method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer having excellent image characteristics, such as image density, resolution and gradation characteristic and an image forming method using this developer relating to the developer used for electrostatic recording devices, such as a copying machine and printer by an electrophotographic photoreceptor development system and image forming method. SOLUTION: This image forming method consists in using a developing device having a developing roller, a regulating member for regulating the layer thickness of the developer supplied onto the developing roller and a photoreceptor and developing the electrostatic latent image formed on the photoreceptor having a photosensitive layer containing oxytitanium phthalocyanine having the largest diffraction peak at a Bragg angle (2θ±0.2 deg.) 27.3 deg. in the X-ray diffraction spectra by CuKα rays by the developer which contains inorganic powder of >=50 in degree of hydrophobing, is 1 to 40 in the absolute value of q when the electrostatic charge quantity of the developer is q (μC/g) and is regulated in the layer thickness d (mm) of the developer on the developing roller so as to attain 0.2<=|q.d|<=10 and the developer for the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developer and a developing method used for a copying machine or an electrostatic recording apparatus by an electrophotographic developing method, and more particularly, to image characteristics such as image density, resolution and gradation. And a method for forming an image using the same.

[0002]

2. Description of the Related Art As a developer used in a copying machine or an electrostatic recording apparatus, a developer is transported by a transport member, and the electrostatic latent image formed on the photoreceptor is visualized by the developer. Is well known. In this developing method, a one-component developer composed of only a toner or a two-component developer composed of a toner and a carrier is generally used. In recent years, various development methods using a one-component developer consisting of toner alone have been proposed because of the advantage that the apparatus can be downsized and maintenance is easy (U.S. Pat.No. 3,909,258, U.S. Pat.No. 4,121,931) etc).

An image forming method using a non-magnetic one-component developer (hereinafter, also referred to as a non-magnetic toner) is performed, for example, as follows using a developing device shown in FIG. That is, a developing roller 44 and a supply roller (toner replenishing roller) 43 are provided in pressure contact with the photoconductor 1 in a toner container 4 installed near the photoconductor 1. More development bias is applied. The toner container 4 contains a one-component developer T made of a non-magnetic toner and is conveyed to a contact surface with the supply roller 44. Further, the non-magnetic toner is carried to the photoconductor side with the rotation of the developing roller 44 so that the electrostatic latent image formed on the surface of the photoconductor 1 is developed.

An image forming method using a magnetic one-component developer (hereinafter, also referred to as a magnetic toner) may be performed, for example, as follows using a developing device shown in FIG. That is, the photosensitive member 1 and the developing roller 44 having the fixed magnet 46 therein are rotated in the direction of the arrow in FIG. The magnetic toner particles T in the developing device 4 are regulated to an appropriate thickness by the regulating member 45 to form a thin layer on the surface of the developing roller 44. The magnetic toner particles T contain 10 to 70% by weight of a ferromagnetic material, and the toner particles come into contact with the surface of the support while being conveyed to the developing section on the surface of the developing roller 44, so that a sufficient triboelectric charge is obtained. Is given. Thus, in the magnetic field of the fixed magnet 46 included in the developing roller 44, a magnetic brush of magnetic toner is formed by the magnetic pole, and the developing unit develops the electrostatic latent image with the magnetic toner in the magnetic field. At this time, an alternating bias is applied to the developing roller 44 as necessary. In these one-component developing systems, it is extremely difficult to form a uniform developer layer, sufficient triboelectricity does not occur, and a poor image with a low image density and a lot of fog is likely to occur.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to stably supply a developer, obtain a thin and uniform developer layer on a developing roller, and reproduce an electrostatic latent image on a photosensitive member with good reproducibility. Another object of the present invention is to provide a one-component developing method in which a sufficient amount of developer is transferred from a developing roller to increase image density and reduce defects such as fog and a one-component developer used in the developing method. .

The present inventors have conducted intensive studies to overcome the problems of the prior art, and as a result, have developed a developing roller, a regulating member for regulating a layer thickness of a developer supplied on the developing roller, and a photosensitive member. A developing device using a method for developing an electrostatic latent image formed on a photoconductor having a photosensitive layer with a developer using the developing device, wherein the photosensitive layer is CuKα.
In the X-ray diffraction spectrum by X-rays, the black angle (2
θ ± 0.2 °) oxytitanium phthalocyanine having a maximum diffraction peak at 27.3 °, the developer contains an inorganic powder having a hydrophobicity of 50 or more, and the charge amount of the developer is q ( μC / g), the absolute value of q is 1 to 40, and the layer thickness d (mm) of the developer on the developing roller is adjusted so that 0.2 ≦ | q · d | ≦ 10. The present inventors have found that the above-mentioned object can be achieved by doing so, and have completed the present invention based on the knowledge.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
In the present invention, the developer contains at least a colorant, a binder resin, and an inorganic powder having a hydrophobicity of 50 or more, and may further contain a charge control agent, a wax, and other additives as necessary. The inorganic powder added in the present invention is not particularly limited as long as the degree of hydrophobicity is 50 or more. Silica, alumina, titania, magnetite,
Ferrite, cerium oxide, strontium titanate,
It is possible to use talc, talcites, silicon nitride, titanium nitride and the like and those obtained by subjecting them to a known hydrophobic treatment. Particularly preferably, silica, alumina and titania can be used. More preferably, it is silica.

The hydrophobizing agent may be chemically fixed to the surface of the inorganic powder using a coupling agent or the like, or may be simply physically fixed and used. The degree of hydrophobicity is preferably 50 or more, more preferably 60 or more. The degree of hydrophobicity is measured by a methanol titration method described later. PH shown when these inorganic powders are dispersed in water
Is not particularly limited, but is preferably 4 to 12
Range. The primary particle size of the inorganic powder is usually 5 nm to 5
μm, preferably 5 nm to 1 μm, and 5 nm to 0.1 μm.
5 μm is more preferred. The addition amount is 0.1 to 5.0 w
t% is preferable, and more preferably 0.1 to 3.0 wt%.
Range. By adding an inorganic powder having a degree of hydrophobicity of 50 or more, the charging characteristics of the blade become better,
Further, the adhesive force to the photoconductor is reduced, and the transfer efficiency is improved.

As a method for adding the inorganic fine particles, known methods can be used without limitation. For example, a Henschel mixer, a chemical mixer, a mechanofusion method, a surffusion method, or the like can be used. Further, the liberation amount of the inorganic powder added to the developer is preferably 5.0% by weight or less. More preferably, the content is 3.0 wt% or less. The amount of free inorganic powder is measured with a particle analyzer manufactured by Yokogawa Electric Corporation. Specifically, the measurement is performed as follows. That is, the developer of the present invention is sucked up by an aspirator using helium as a carrier gas, and is measured by a plasma emission analysis in a measurement unit. Advantageous inorganic powder external additives are not synchronized with the emission of carbon atoms in the binder resin or the like, and are therefore quantified by their emission intensity.

As the binder resin, various known resins suitable for a developer can be used. For example, styrene resin, vinyl chloride resin, rosin-modified maleic resin, phenol resin, epoxy resin, saturated polyester resin, unsaturated polyester resin, low molecular weight polyethylene, low molecular weight polypropylene, ionomer resin, polyurethane resin, silicone resin, ketone resin , An ethylene-ethyl acrylate copolymer, a xylene resin, a polyvinyl butyral resin, and the like. Preferred examples of the resin used in the present invention include a styrene resin, a saturated or unsaturated polyester resin, and an epoxy resin. . These resins may be used alone or in combination. These resins are used as a non-crosslinked resin, a crosslinked resin, or a mixture thereof according to the fixing method.

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 monomer as needed. As a method for producing the binder resin, there are bulk polymerization, suspension polymerization, solution polymerization, emulsion polymerization, and the like, but any method can be used regardless of the polymerization method.

The polyester resin is a divalent carboxylic acid unit.
Monomer and dihydric alcohol monomer and, if necessary, trivalent or higher
Of polyhydric carboxylic acid monomer and polyhydric alcohol monomer
High molecular weight and condensation reaction by condensation or urethanization
Obtained by As a dihydric alcohol monomer,
Ethylene glycol, diethylene glycol, triethyl
Len glycol, 1,2-propylene glycol, 1,
3-propylene glycol, 1,4-butanediol,
Neopentyl glycol, 1,4-butenediol, etc.
Diols, bisphenol A, polyoxyethylene
Bisphenol A, polyoxypropylene bisphenol
Bisphenols such as phenol A, other divalent
Alcohol monomer. Monovalent carboxylic acid
Isomers include isophthalic acid, terephthalic acid and adipine
Acid, sebacic acid, diphenic acid, naphthalenedicarboxylic acid
Acids, cyclohexanedicarboxylic acids, anhydrides of these acids
Or those containing lower alkyl ester as the main component
I can do it. Trivalent or higher polycarboxylic acids include trimer
Lithic acid, cyclohexanetricarboxylic acid, naphthalent
Licarboxylic acid, butanetricarboxylic acid, hexanetrica
Rubonic acid, octanetetracarboxylic acid, and these acids
Anhydrides and the like. More than 3 valencies
As the monohydric alcohol monomer, trimethylolethane,
Trimethylolpropane, glycerin, pentaerythrri
And tolls. Molecular weight of these binder resins
And molecular weight distribution are adjusted for the purpose of adapting to the developing device and fixing method.
Can be adjusted, but using these binder resins
When the developer is used as a monochromatic developer, preferably,
The storage elastic modulus in dynamic viscoelasticity measurement at 150 ° C. was 1.
0x10^Two(Pa) ≦ G ′_1%≦ 1.0 × 10^Four(Pa), and
1.0 ≦ G ′_1%/ ≦ G '_30%≤ 10.0 (G '_1%Is distortion 1
% Storage modulus, G ′ _30%Is 30% distortion
Storage elastic modulus) for full color
When used as a color developer, preferably 120 ° C
Storage elastic modulus in dynamic viscoelasticity measurement at 1.0 × 10
^Two(Pa) ≦ G ′_1%≦ 1.0 × 10^Four(Pa) and 1.0 ≦
G '_1%/ ≦ G '_30%≤ 10.0 (G '_1%Is at 1% distortion
G ′_30%Is the storage at 30% strain
Storage elastic modulus). The measurement of dynamic viscoelasticity is
Parallel play by MR-500 manufactured by UBM
At a frequency of 1 Hz.

The coloring agents used in the present invention include carbon black, lamp black, iron black, ultramarine blue, nigrosine dye, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa Yellow G, rhodamine dyes and pigments, chrome yellow, quinacridone, Any known dyes or pigments such as benzidine yellow, rose bengal, triallylmethane dyes, monoazo dyes, disazo dyes and condensed azo dyes can be used alone or in combination. In the case of a full-color developer, yellow uses benzidine yellow, monoazo dyes and pigments, condensed azo dyes and pigments, magenta uses quinacridone, rhodamine dyes and monoazo dyes, cyan uses phthalocyanine blue, and black uses carbon black. Is preferred. The coloring agent is used in an amount of usually 1 to 20 parts by weight based on 100 parts by weight of the binder.

The magnetic particles used in the magnetic toner of the present invention may be used in an environment of a copying machine or the like (around 0 ° C. to 60 ° C.).
A ferromagnetic substance showing ferrimagnetism or ferromagnetism, such as magnetite (Fe ₃ O ₄ ), maghematite (γ-Fe ₂ O ₃ ), an intermediate between magnetite and maghematite, ferrite (M _X Fe _3-X O ₄ ; wherein M is M
n, Fe, Co, Ni, Cu, Mg, Zn, Cd, etc. or a mixed crystal thereof) or BaO.6Fe
Hexagonal ferrite such as ₂ O ₃ , SrO · 6Fe ₂ O ₃ , Y ₃ F
_{e 5 O 12, Sm 3 Fe} 5 O garnet-type oxides such as _12, C
rutile oxide such as rO ₂ , Fe, Mn, Ni, Co,
Among metals such as Cr and other ferromagnetic alloys, 0 ° C to 6 ° C
Those exhibiting ferromagnetism and ferrimagnetism at around 0 ° C. are mentioned. Among them, magnetite, maghematite, intermediate particles of magnetite and maghematite and the like have an average particle size of 3 μm or less,
More preferably, fine particles of about 0.05 to 1 μm are preferable in terms of performance and cost. The shape of the magnetic particles is hexahedral, 8
It can be used irrespective of a face, an irregular shape, or a spherical shape. Further, the above magnetic particles are not limited to being used alone, and two or more kinds can be used in combination. The developer of the present invention is a binder resin,
It consists of additives and colorants, but may further contain other components if desired.

As the charge controlling agent, known ones can be used, and particularly preferred are the following general formulas (I) to (V).
And a compound represented by the general formula (I), (III) or (I
Metal complex or salt of the compound represented by V), general formula (IV)
The boron complex of the compound represented by these is mentioned.

[0016]

Embedded image (Where A, B, C, and D represent an aromatic ring which may have a substituent, and Q represents a direct bond or a divalent linking group). In the formula (I), examples of the aromatic ring represented by A, B, C, or D include a benzene ring, a naphthalene ring, an anthracene ring, and a phenanthrene ring. Rings are preferred. When these aromatic rings have a substituent, examples of the substituent include a hydrocarbon group, an alkoxy group, an alkylthio group, a dialkylamino group, a nitro group, a chinano group, a hydroxyl group, and a halogen atom. Of these, halogen atoms are preferred. Q represents a direct bond or a divalent coupler, and examples of the divalent coupler include an oxygen atom, a sulfur atom, an alkylimino group, an alkylene group, and an alkylidene group. An alkylene group having 1 to 4 or an alkylidene group having 2 to 4 carbon atoms is preferable. When used as the metal salt of the formula (I), the metal ion is
Alkali metal ions or alkaline earth metal ions are preferred, and sodium ions or potassium ions are more preferred.

[0017]

Embedded image (In the formula, n and m represent an integer of 0 or more, and n + m is 4 to
It is 10. R ¹ and R ² each independently represent a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 12 carbon atoms, and R ³ and R ⁴ each independently represent a hydrogen atom or a carbon atom having 1 to 5 carbon atoms. Represents a hydrocarbon group. In the formula, R ^{1 to} R ⁴ are preferably a hydrogen atom or an alkyl group of hydrocarbons 1 to 5, and among them, R ¹ and R ^{2 each} have 3 to 3 carbon atoms.
5 is more preferably an alkyl group wherein R ³ and R ⁴ are hydrogen atoms. Also, n + m is preferably 6 to 9,
8 is most preferred.

[0018]

Embedded image (In the formula, R ⁵ and R ⁶ are preferably an alkyl group having 3 to 5 carbon atoms. When a metal complex or salt of the compound of the formula (III) is used, the metal may be divalent or trivalent. Preferably, chromium, aluminum, or zinc is more preferable.

[0019]

Embedded image (In the formula, E and F represent an aromatic ring which may have a substituent.) In the formula, the aromatic ring of E and F is preferably a benzene ring or a naphthalene ring, and more preferably a benzene ring. preferable. When these aromatic rings have a substituent, examples of the substituent include a hydrocarbon, an alkoxy group, an alkylthio group, a dialkylamino group, a nitro group, a cyano group, a hydroxyl group, and a halogen atom. Are preferred. When a metal complex or a salt of the compound of the formula (IV) is used, the metal is preferably divalent or trivalent, and more preferably chromium, aluminum, or zinc.
Further, a boron complex of the compound of the formula (IV) is also preferably used.

[0020]

Embedded image (Wherein R ⁷ and R ¹⁰ are each independently a hydrogen atom,
A halogen atom, a hydrocarbon group having 1 to 5 carbon atoms, a nitro group,
Represents a cyano group, and R ¹¹ and R ¹² each independently represent a hydrogen atom or an N-phenylcarbamoyl group. Also, M
Represents a trivalent metal, and X ⁺ represents a proton, an ammonium ion, or an alkali metal ion. In the formula, at least one of R ^{7 to} R ¹⁰ is preferably a nitro group or a chlorine atom. M is preferably chromium or iron, and X ⁺ is preferably a sodium ion or a potassium ion.

For the purpose of improving the fixing property, the melting point is 50 ° C.
100 parts by weight of a low melting point wax such as paraffin wax, higher fatty acid, fatty acid amide, ester wax, ketone wax, rice wax, Fischer-Tropsch wax in an amount of 0.1 to 3 parts per 100 parts of the binder resin.
0 parts by weight may be added. By adding these low melting point waxes, a developer having good fixability can be obtained. The preferred range of the melting point of the low-melting wax is from 50 to 100 ° C, more preferably from 60 to 90 ° C. Also, DS
The half width of the endothermic peak corresponding to the melting point in the C measurement is preferably narrow. The half width is preferably 20 ° C. or less, more preferably 10 ° C. or less. The melting point was measured using DSC2.
Using 20 U (manufactured by Shimadzu Corporation), the endothermic curve measured at a heating rate of 10 ° C./min is determined from the intersection between the tangent having the largest slope and the base line on the low temperature side. The crystal morphology of these low-melting waxes in the developer is not particularly limited. The dispersion diameter is preferably 3.0 μm or less in the major axis.

Further, 0.1 to 30 parts by weight of polypropylene wax, polyethylene wax, modified polypropylene wax, modified polyethylene wax and the like can be added. Further, 0.01 to 20 parts by weight of various silicone oils, modified silicone oils, silicone varnishes and modified silicone varnishes can be added.

An inorganic or organic fine powder can be added in combination with an inorganic fine powder having a hydrophobicity of 50 or more. As inorganic fine powder, magnetite, ferrite, cerium oxide, strontium titanate, barium titanate, talc, talcites, silicon nitride, silicon carbide, titanium nitride,
As the organic fine powder such as silica, resin fine particles composed of a styrene resin, an acrylic resin, a benzoguanamine resin, a melamine resin, or the like can be used as a fluidity adjusting agent or a charge adjusting agent, but are not limited to the exemplified compounds. The addition amount is used so as to be 0.05 to 10 parts by weight with respect to 100 parts by weight of the developer.

Further, a lubricant such as metal soap or metal stearate can be added internally or externally. These additives are usually used in an amount of 0.05 to 1 based on 100 parts by weight of the developer.
Used to be 0 parts by weight.

The production of the developer according to the present invention from the above-mentioned components can be carried out according to a conventional method. Usually, first, a binder resin, an additive, a colorant, a charge control agent, and other components to be added as needed are uniformly dispersed and mixed by a mixer, and then the mixture is sealed in a closed kneader.
Alternatively, the mixture is melt-kneaded by a single-screw or twin-screw extruder, cooled, crushed by a crusher, a hammer mill, or the like, finely crushed by a jet mill, a high-speed rotor rotary mill, or the like, and then classified by an air classifier (for example, an inertial classification system). Elbow jet, centrifugal classification microplex, DS separator, etc.). Further, it can also be produced by a dispersion polymerization method such as a suspension polymerization method and an emulsion polymerization method.

In the image forming method using the one-component developer of the present invention, when the charge amount of the developer is q (μC / g),
The absolute value of q is 1 to 40, and the layer thickness d (mm) of the developer on the developing roller needs to be adjusted to 0.2 ≦ | q · d | ≦ 10. The method of measuring the charge amount q and the layer thickness d of the developer is measured by a method described later.

When the charge amount of the developer is high, the developer having a high charge amount adheres strongly to the developing roller due to electrostatic force and covers the roller surface when frictional charging is applied by the regulating member. Without this, it is difficult to uniformly charge the entire developer layer. That is, the charge amount is high near the surface of the developing roller, and the charge amount tends to decrease as the distance from the surface of the developing roller increases. For this reason, when a developer having a high charge amount is used, if the layer thickness of the developer is increased, the charge amount of the developer existing in a portion distant from the developing roller, that is, the charge amount of the developer close to the photoconductor is low. However, this causes fogging and non-uniform solid images.

On the other hand, when the charge amount of the developer is low, the developer does not strongly adhere to the surface of the developing roller when frictional charging is applied by the regulating member. Charge. However, if the amount of charge of the developer is low and the layer thickness of the developer is small, it causes ghosts and non-uniform solid images. That is, when the developer on the developing roller is developed under the condition that a large amount of the developer is developed at a time, if the layer thickness of the developer is thin, the entire developer layer is uniformly charged, but the developing roller is supplied to the developing roller. The charge amount of the developer further decreases, and finally the adhesion between the developers due to van der Waals force or magnetic force or the adhesion force between the developer and the developing roller becomes larger than the electrostatic force applied to the developer by the development electric field, so that the developer is not developed. To prevent this phenomenon, it is necessary to increase the layer thickness of the developer and increase the supply amount of the developer to the electrostatic latent image. For the above reasons, when the charge amount q of the developer is high, the layer thickness d of the developer is small, and when the charge amount q is low, the layer thickness d of the developer needs to be set thick. Therefore, appropriate ranges are generated for q and | q · d |.

As a result of intensive studies, the present inventors have found that the absolute value of q is 1 to 40, preferably 1 to 30, and the layer thickness d (mm) of the developer on the developing roller is 0.2 ≦ | q · d | ≦ 1
It has been found that a good image can be obtained by adjusting the value to 0. In order to adjust q and d to the above ranges, it is necessary to adjust the charging ability of the developer and the material of the regulating member for regulating the layer pressure and / or the pressing of the regulating member.

Further, in the present invention, the X-ray diffraction spectrum by CuKα ray shows the black angle (2θ ± 0.
2 ゜) It is essential to use a photoreceptor containing oxytitanium phthalocyanine having a maximum diffraction peak at 27.3 ゜. In other words, small size like one-component development system
In high-speed copiers and printers, the charge must be rapidly attenuated in the exposure step and the charge removal step. Therefore, in order to obtain a good image, the charge amount q of the developer and the thickness of the developer layer described above are required. It is essential to use the photoreceptor containing oxytitanium phthalocyanine of the present invention, which has high sensitivity to near-infrared light for semiconductor lasers and excellent electrical characteristics together with the condition of d.

The crystalline oxytitanium phthalocyanine is described in, for example, FIG. 2 of JP-A-62-67094.
(Referred to as type II in the same gazette), JP-A-2-8256
FIG. 1 of Japanese Unexamined Patent Publication No.
FIG. 1, FIG. 1 of JP-A-63-20365, Journal of the Society of Electrophotography, Vol. 92 (issued in 1990), No. 3, 250-25
It is shown on page 8 (referred to as Y type in the same publication), and is usually 7.4 通常, 9.7 ゜ and 27.3 ゜ in addition to 27.3 ゜.
A diffraction peak is shown at 4.2 °. In the present specification, the crystalline oxytitanium phthalocyanine used in the present invention will be referred to as a Y-type in accordance with the academic publication.

The intensity of the diffraction peak may vary depending on the crystallinity, the orientation of the sample, and the measurement method. However, in the measurement by the Bragg-Brentano concentration method which is generally used when performing X-ray diffraction of powder crystals, The Y-type crystal has a maximum diffraction peak at 27.3 °. When measured by a thin film optical system (generally called a thin film method or a parallel method), the maximum diffraction peak at 27.3 ° may not be the maximum diffraction peak depending on the state of the sample. It is considered that they are oriented in the direction.

In the present invention, a charge generator other than Y-type oxytitanium phthalocyanine may be mixed and used for the purpose of adjusting the sensitivity and the like.
The charge generating substance is α-type oxytitanium phthalocyanine,
If only a titanium-containing phthalocyanine compound such as β-oxytitanium phthalocyanine is mixed, the proportion of the Y-type oxytitanium phthalocyanine in the charge generator is usually 30% by weight or more, preferably 50% by weight or more, and more preferably Is preferably 70% by weight or more. Further, if it is mixed with a charge generator other than the titanium-containing phthalocyanine compound, the amount of the Y-type oxytitanium phthalocyanine in the charge generator is usually 40% by weight or more, preferably 60% by weight or more, more preferably 8
The content is preferably 0% by weight or more.

In the above-described X-ray diffraction using CuKα radiation, when an organic photoreceptor containing oxytitanium phthalocyanine having a maximum diffraction peak at a black angle (2θ ± 0.2 °) of 27.3 ° is used, the residual potential is reduced. It is possible to prevent an increase in the adhesive strength of the developer due to the accumulation of the developer, and it is particularly effective to use the developer in combination with the developer of the present invention. Further, the developing method and the developer of the present invention have a photoreceptor having a diameter of 40.
It is effective when it is not more than 30 mm, and particularly effective when it is not more than 30 mm. Specifically, if the distance from the exposure position on the photoconductor to the development position on the photoconductor along the rotation direction of the photoconductor is d1 (mm), and the peripheral speed of the photoconductor is v (mm / sec), d1 / In the developing device where v ≦ 0.50 (sec), more preferably, the effect is more exerted in the developing device where d1 / v ≦ 0.40 ec).

The particle size distribution of the developer is the number average particle size of the developer.
(Dn50) and the volume average particle size (Dv50) are in the range of 1.0 ≦ D
It is preferable that v50 / Dn50 ≦ 1.3. More preferably, the range is 1.0 ≦ Dv50 / Dn50 ≦ 1.2. In addition, when the particle size distribution of the developer satisfies the following conditions, more excellent performance is exhibited. 5 μm or less: 3 number% or more 8 to 12.7 μm: 40 number% or less 16 μm or more: 2 volume% or less D ₅₀ : 4 to 10 μm The particle size distribution in the present invention is measured by a method described later.

The degree of sphericity of Wardell is 0.4-1.
0, more preferably 0.5-1.
0. The degree of Wardell's sphericity is measured by the method described below. As a method of spheroidization, a method of applying mechanical energy or heat energy to a developer obtained by a pulverization method such as mechanofusion or surffusion to form a spherical shape, and a method of suspension polymerization, emulsion polymerization and aggregation thereof. A so-called polymerization toner method can be used. The particle size distribution of the developer and the degree of sphericity of the Wardel relate to the uniformity of charge and the fluidity of the developer, and a developer satisfying the above conditions has excellent charge characteristics and fluidity, and excellent developability and transferability.

An example of the image forming method of the present invention will be specifically described using the image forming apparatus shown in FIG. The photoreceptor 1 is formed by applying a photosensitive conductive material to an outer peripheral surface of a conductor such as aluminum to form a photosensitive layer. A charging device 2, an exposure device 3, a developing device 4, a transfer device 5, and a cleaning device 6 are arranged along the outer peripheral surface of the photoconductor 1. The charging device 2 includes, for example, a well-known scorotron charger,
The surface of the photoconductor 1 is uniformly charged to a predetermined potential by a roller charger or the like. The exposure device 3 applies L to the photosensitive surface of the photoconductor 1.
This is to form an electrostatic latent image on the photosensitive surface of the photoconductor 1 by performing exposure with ED, laser light, or the like.

The developing device 4 includes an agitator 42, a supply roller 43, a developing roller 44, and a regulating member 45, and stores a one-component developer T therein. A replenishing device 41 for replenishing the developer T to the developing device 4 as necessary.
(Not shown) may be attached, and the replenishing device 41 can replenish the developer T from a container such as a bottle or a cartridge. The supply roller 43 is made of a conductive sponge or the like, and is in contact with the developing roller 44. The developing roller 44 is disposed between the photoconductor 1 and the supply roller 43. The supply roller 43 and the developing roller 44 are rotated by a rotation drive mechanism. The supply roller 43 carries the stored developer T and supplies it to the developing roller 44. The developing roller 44 includes a supply roller 43.
Is carried and brought into contact with the surface of the photoconductor 1. The developing roller 44 is made of iron, stainless steel,
It is made of a metal roller of aluminum, nickel, or the like, or a resin roller in which a metal roller is coated with a silicon resin, a urethane resin, a fluororesin, or the like. The surface of the developing roller may be smoothed or roughened as necessary. The regulating member 45 is formed of a resin blade such as a silicone resin or a urethane resin, a metal blade such as stainless steel, aluminum, copper, brass, phosphor bronze, or the like, or a blade obtained by coating a metal blade with a resin. This regulating member 45
Is in contact with the developing roller 44 and is pressed against the developing roller 44 by a predetermined force (a typical blade linear pressure is 5 to 500 g / cm) by a spring or the like.
May be provided with a function of charging the developer T by frictional charging with the developer T. The agitator 42 is rotated by a rotation drive mechanism, and agitates the developer T and conveys the developer T to the supply roller 43 side. A plurality of agitators 42 may be provided with different blade shapes and sizes.

The transfer device 5 includes a transfer charger, a transfer roller, a transfer belt, and the like, which are arranged to face the photosensitive member 1. The transfer device 5 applies a predetermined voltage value (transfer voltage) having a polarity opposite to the charged potential of the developer T, and transfers an image formed of the developer formed on the photoconductor 1 to the recording paper P. . The cleaning device 6 is composed of a cleaning member such as a urethane blade or a fur brush. The cleaning device scrapes the residual developer adhered to the latent image holding member 1 with the cleaning member, and collects the residual developer.

The fixing device 7 includes an upper fixing member 71 and a lower fixing member 72, and has a heating device 73 inside the upper or lower fixing member. As the fixing member, a known heat fixing member such as a fixing roller in which a metal tube made of stainless steel, aluminum, or the like is coated with a silicone resin, a fixing roller in which a fluorine resin is coated with a fixing resin, a fixing sheet, or the like can be used. Further, a releasing agent such as silicone oil may be supplied to the fixing member in order to improve releasability. Further, a mechanism for forcibly applying pressure to the upper fixing member and the lower fixing member by a spring or the like may be employed. Recording paper P
When the developer T transferred above passes between the upper fixing member 71 and the lower fixing member 72 heated to a predetermined temperature, the developer T is heated to a molten state, cooled after passing through, and cooled. The developer T is fixed on P.

[0041]

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

[Production Method of Developer A] Polyester 100
Parts by weight, cyan pigment masterbatch (Pig Blue 15: 3/40%
After dispersing and mixing 10 parts of a master batch and 1 part by weight of a charge control agent ("LR-147" manufactured by Nippon Carlit Co., Ltd.), the mixture was melt-kneaded using a twin-screw extruder. After cooling, it was coarsely pulverized by a hammer mill and then finely pulverized by a supersonic jet mill pulverizer. The obtained powder was classified with an air classifier, and the particle size was 5 to 30.
A part of μm was obtained. Further, silica having a hydrophobicity of 70 was externally added using a Henschel mixer to obtain a developer A having the physical properties shown in Table 1.

[Developer B Production Method] A developer B having the physical properties shown in Table 1 was obtained in the same manner as the developer A production method except that the urethane-modified polyester was used.

[Production Method of Developer C] Developer A except that a charge controlling agent (“TN-105” manufactured by Nippon Carlit Co., Ltd.) is used.
Developer C having the physical properties shown in Table 1 was obtained in the same manner as in the production method.

[Production Method of Developer D] Developer D having the physical properties shown in Table 1 was obtained in the same manner as in the production method of Developer A except that silica having a hydrophobicity of 40 was used.

[Developer E Production Method] A developer E having the physical properties shown in Table 1 was obtained by changing the classification conditions in the same manner as in the method for producing the developer D except that silica having a hydrophobicity of 30 was used. Was.

[Method of Manufacturing Organic Photoconductor] In X-ray diffraction using CuKα ray, black angle (2θ ± 0.2 °) 27.
Film thickness of 200 parts by weight of oxytitanium phthalocyanine having diffraction peaks at 3 °, 24.2 °, 9.7 ° and 7.4 ° and 100 parts by weight of polyvinyl butyral.
4 μm charge generation layer, 70 parts by weight of N-methyl-3-carbazole carbaldehyde diphenylhydrazone, 2 parts by weight of p-nitrobenzoyloxybenzalmalonenitrile and 100 parts by weight of polycarbonate resin (NOVAREX 8025A manufactured by Mitsubishi Chemical Corporation) 15μ film thickness
A 30 mmφ cylindrical organic photoreceptor having a laminated photosensitive layer in which a m-th charge transfer layer was laminated on an Al substrate was prepared.

[Image Forming Apparatus] The image forming apparatus shown in FIG. 1 was used using a photosensitive member having an outer diameter of 30 mm prepared by the above method.

[Examples and Comparative Examples] The above-mentioned developers A to
Table 1 shows the results obtained by applying E to the above-described image forming apparatus and evaluating the actual shooting in an environment of a temperature of 25 ° C. and a humidity of 60% RH.
In Examples and Comparative Examples, the material of the regulating member was a urethane rubber blade, and the adjustment of the charge amount q and the layer thickness d of the developer were adjusted by pressing and the angle of the regulating member.

[0050]

[Table 1]

The various physical properties in the present invention are measured by the following methods. 1. Degree of hydrophobicity of silica Methanol titration method (1) A sample 0.20 (0.20 ± 0.01 g) is collected in a beaker, 50 ml of pure water is added, and while stirring with a magnetic stirrer, methanol is dropped below the liquid surface. inject. (2) The point at which the sample is no longer observed on the liquid surface is defined as the end point. (3) The degree of hydrophobicity is calculated from the amount of methanol used at the end point by the following equation. Hydrophobicity = Methanol usage × 100 / (50 + Methanol usage)

2. Method of Measuring Coulence and Developer Layer Thickness (1) An appropriate amount of developer is charged into a developing tank, and 30 sheets are actually photographed with a real machine under a condition of 5% printing rate. (2) The toner on the developing roller is sucked using the powder charge amount measuring device 210HS (manufactured by Trek). The outline of the device is shown in the figure below. (3) The charge amount q and the layer thickness d of the developer are obtained from the following measured values and the following formula. Suction weight A (g): Suction suction unit weight (g) -Suction unit weight before suction (g) Charge amount B (μC): Readout value of powder charge amount measuring device Suction diameter C (cm): Development after suction Measured with a vernier caliper from the tank Charge amount q = B / A Developer layer thickness d = Measured with a micrometer

3. Particle size distribution of developer Particle size distribution measuring method (1) Coulter Counter Multisizer II type (manufactured by Coulter) is used. The aperture diameter is 100 μm. (2) a suitable amount of a surfactant (preferably an alkenylbenzene sulfonate) as a dispersant is added to the electrolytic solution Isoton II,
Dispersion treatment is performed for 30 to 60 seconds with an ultrasonic disperser, and the particle size distribution is measured using the Coulter Counter Multisizer II.

4. The sphericity (1) Coulter Counter Multisizer II (manufactured by Beckman Coulter, Inc.), finding a volume average particle diameter Dv _50. (2) The BET specific surface area is determined by a nitrogen adsorption method using a flow soap Model 2300 (manufactured by Shimadzu Corporation). (3) The Wardel sphericity is obtained by the following equation. The specific surface area / BET specific surface area when it is assumed a more shape sphericity = volume average particle diameter Dv ₅₀

[0055]

According to the present invention, it is possible to provide a one-component developer excellent in image characteristics such as image density, resolution and gradation, and an image forming method using the same.

[0056]

[Brief description of the drawings]

FIG. 1 is a schematic view of an example of an image forming apparatus for a non-magnetic one-component developer used in an image forming method of the present invention.

FIG. 2 is a schematic view of an example of an image forming apparatus for a magnetic one-component developer used in the image forming method of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoconductor 2 charging device 3 exposure device 4 developing device 5 transfer device 6 cleaning device 7 fixing device 41 replenishing device (not shown) 42 agitator 43 supply roller 44 developing roller 45 regulating member 46 fixed magnet 71 upper fixing member 72 lower fixing Member 73 Heating device T Toner P Recording paper

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G03G 15/08 507 G03G 15/08 507L (72) Inventor Teruki Senoguchi 1 Fukudacho, Joetsu-shi, Niigata Mitsubishi Chemical Naoetsu Office (72) Inventor Masakazu Sugihara 1 Fukuda-cho, Joetsu-shi, Niigata Mitsubishi Chemical Corporation Naoetsu Office F-term (Reference) AE04 EA13 EA14

Claims (6)

[Claims] An X-ray diffraction spectrum by CuKα radiation using a developing device having a developing roller, a regulating member for regulating a layer thickness of a developer supplied on the developing roller, and a photoreceptor. 0.2%) An electrostatic latent image formed on a photoreceptor having a photosensitive layer containing oxytitanium phthalocyanine having a maximum diffraction peak at 27.3 ° contains an inorganic powder having a hydrophobicity of 50 or more, When the charge amount of the developer is q (μC / g), the absolute value of q is 1 to 40, and the layer thickness d (mm) of the developer on the developing roller is 0.2 ≦ | q · d An image forming method using a one-component developer, wherein the image is developed with a developer adjusted to satisfy | ≦ 10. 2. The developer according to claim 1, wherein the ratio of the number average particle diameter (Dn50) to the volume average particle diameter (Dv50) is 1.0 ≦ Dv50 / Dn50 ≦
1.3, and the degree of Wardel's sphericity is 0.4 to 1.
2. The image forming method using a one-component developer according to claim 1, wherein the value is 0. 3. The developer contains 0.1 to 5.0 wt% of inorganic powder.
An image forming method using the one-component developer according to claim 1, wherein the developer is contained. 4. An electrostatic latent image formed on a photosensitive member having a photosensitive layer using a developing device having a developing member and a regulating member for regulating a layer thickness of a developer supplied onto the developing roller. A developer using a method of developing an image with a developer, wherein the photosensitive layer has a maximum diffraction peak at a black angle (2θ ± 0.2 °) of 27.3 ° in an X-ray diffraction spectrum by CuKα radiation. It contains oxytitanium phthalocyanine, the developer contains an inorganic powder having a hydrophobicity of 50 or more, and when the charge amount of the developer is q (μC / g), the absolute value of q is 1 to 40. A one-component developer wherein the layer thickness d (mm) of the developer on the developing roller is adjusted so that 0.2 ≦ | q · d | ≦ 10. 5. The developer according to claim 1, wherein the ratio of the number average particle diameter (Dn50) to the volume average particle diameter (Dv50) is 1.0 ≦ Dv50 / Dn50 ≦
1.3, and the degree of Wardel's sphericity is 0.4 to 1.
The one-component developer according to claim 4, wherein 0. 6. The developer contains 0.1 to 5.0 wt% of inorganic powder.
The one-component developer according to claim 4, wherein the one-component developer is contained.