JPH07175265A - Developer for electrostatic charge image developing and image forming method - Google Patents

Abstract

PURPOSE:To attain stable triboelectrifying property under various environments without being influenced by the change of environment by using a specific toner and carrier. CONSTITUTION:The toner contains a toner particle and titanium oxide and the toner particle contains at least a coloring agent directly obtained by suspension polymerization method and a resin component. The resin component has 5000-50000 molecular weight for at least one of molecular weight peaks of the molecular weight distribution measured by GPC and has one or more kind of a polar component. The titanium oxide has 0.01-0.2mum average particle diameter and 20-98% hydrophobicity. The carrier has 5-100mum average particle diameter, <=3.0g/cm<3> bulk density and magnetic property of 30-150emu/cm<3> intensity of magnetization sigma1000 in magnetic field of 1000Oe after saturation and >=25emu/ cm<3> intensity of magnetization sigmar in magnetic field of zero Oe, <300Oe coercive force and satisfies a condition expressed by an equation. In the equation, sigma300 represents the intensity of magnetization in 300Oe.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method in which an electrophotographic photosensitive member is used as a latent image carrier to form a latent image, the latent image is visualized with a developer, and transferred. The present invention relates to a developer for developing an electrostatic charge image and a method for forming an image.

[0002]

BACKGROUND OF THE INVENTION Electrophotography is described in US Pat. No. 2,297,
As described in Japanese Patent Application No. 691 etc., a number of methods are known, and generally, a photoconductive substance is used to form an electric latent image on a photoreceptor by various means, and then the latent image is formed. The image is developed with toner, the toner image is transferred to a transfer member such as paper, if necessary, and then fixed by heating, pressure, solvent vapor or the like to obtain a copy. Further, as a method of developing with a toner or a method of fixing a toner image, various methods have been conventionally proposed, and a method suitable for each image forming process is adopted.

Conventionally, toners used for these purposes are generally toners having a desired particle size by a fine pulverizer and a classifier after melt-mixing a colorant consisting of dyes and pigments in a thermoplastic resin and uniformly dispersing them. Has been manufactured.

While this method of manufacture can produce fairly good toners, it does have certain limitations, ie, the choice of toner materials. For example, the resin colorant dispersion must be sufficiently brittle to be comminuted in an economically feasible manufacturing apparatus. However, if the resin colorant dispersion is made brittle in order to satisfy such requirements, the particle size range of the particles formed when actually pulverized at a high speed tends to be wide, and in particular, a relatively large proportion of fine particles is The problem of inclusion arises. Further, such a brittle material is likely to undergo further fine pulverization or pulverization when used for developing such as a copying machine. Further, in this method, it is difficult to completely uniformly disperse solid fine particles such as a colorant in the resin,
Depending on the degree of dispersion, fog may increase, image density may decrease, and color mixture and transparency may be poor. Therefore, attention must be paid to dispersion. In addition, the exposure of the colorant on the fracture surface may cause fluctuations in the developing characteristics.

On the other hand, in order to overcome the problems of the toner by the pulverization method, the production of the toner by the suspension polymerization method is disclosed in Japanese Patent Publication Nos. 36-10231, 43-10799 and 51-14895. A method has been proposed. In the suspension polymerization method, a polymerizable monomer, a colorant, a polymerization initiator, if necessary, a crosslinking agent, a charge control agent,
After other additives are uniformly dissolved or dispersed to form a monomer composition, the monomer composition is dispersed in a continuous phase containing a dispersion stabilizer, for example, an aqueous phase using a suitable stirrer. At the same time, a polymerization reaction is performed to obtain toner particles having a desired particle size.

Since this method does not include a crushing step at all, the toner does not need to be brittle, a soft material can be used, and the colorant is not exposed on the surface of the particles. It has the advantage of having excellent triboelectric charging properties. Further, since the classification process can be omitted, there are great cost reduction effects such as energy saving, time reduction, and process yield improvement.

As described above, the polymerized toner has many advantages, but from the viewpoint of higher image quality and high durability of electrophotography in recent years, sufficient toner has not been obtained yet.

The polymerized toner is characterized by its manufacturing method.
Of the various additives added to the monomer composition, those having polarity are likely to be unevenly distributed on the toner surface and its vicinity. This feature makes it possible to reduce the amount of additives used for imparting various toner characteristics, but on the other hand, in view of improving image quality, especially maintaining high image quality, it can be used as a sleeve, carrier, etc. There is a problem that the deterioration of the toner surface due to the rubbing of the toner greatly affects the toner characteristics.

Further, since the polymerized toner has such characteristics, it is generally susceptible to temperature and humidity, and problems such as excessive charge amount under low humidity and insufficient charge amount under high humidity occur. There is an urgent need to develop a toner having a stable charge amount even in the environment.

In general, the carrier that constitutes the two-component developer is a conductive carrier typified by iron powder and a so-called insulating carrier in which the surface of iron powder, nickel, ferrite or the like is coated with an insulating resin. Be separated. When an alternating electric field is applied to obtain high image quality, if the resistance of the developer carrier is low, the latent image potential leaks to the carrier, and a good image cannot be obtained. When the carrier core is electrically conductive, it is preferably used by coating, and ferrite having a high resistance to some extent is preferably used as the core material.

Further, since iron powder has a high magnetic force, the developer brush becomes hard in the developing area where the developer toner is developed, and therefore, the developer brush is likely to cause crevices or rustling, and thus a high quality image is obtained. Is difficult to obtain. Therefore,
Ferrite is also preferably used in order to reduce the magnetic force of the carrier and improve the image quality.

To form a high-quality image, Japanese Patent Laid-Open No. 59-1
No. 04663 discloses that the saturation magnetization value of the carrier is 50 em.
It has been proposed that a satisfactory image free from crimping can be obtained by setting the ratio to u / g or less, but the reproducibility of fine wires is improved by using a carrier whose saturation magnetization value is gradually decreased, but the magnetic pole As the distance from the carrier increases, the phenomenon in which the carrier adheres to the electrostatic image carrier, that is, the so-called photosensitive drum (carrier adhesion) becomes remarkable.

Further, Japanese Patent Publication No. 4-3868 proposes to use a so-called hard ferrite having a coercive force of 300 Gauss or more as a carrier. However, this is a system for mastering the carrier of hard ferrite having a high coercive force, and an increase in the size of the device cannot be avoided. In order to realize a compact high-quality color copier,
It is preferable to use a developer carrier using a fixed magnetic core. In this case, the hard carrier having a high coercive force has a problem that the transportability is rather deteriorated due to its self-aggregating property.

Further, Japanese Patent Application Laid-Open No. 2-88429 proposes to use a hard ferrite composed of a magnet-plumbite phase containing a spinel phase and a lanthanoid-type element as a carrier. Since it has conductivity, in a system in which development is performed by an alternating electric field for obtaining a higher quality image, it is not preferable in that development is disturbed because charges leak through carriers.

Therefore, it is necessary that the resistance of the carrier is higher than a certain level in the system for developing by the alternating electric field.

As described above, no sufficient developer carrier has been obtained which can prevent the carrier from adhering and satisfy the high image quality, particularly the reproducibility of highlights.

On the other hand, as a matter of course, the electrophotographic photosensitive member is required to have predetermined sensitivity, electric characteristics, and further optical characteristics according to the electrophotographic process to which it is applied. However, not only that, the durability of the photoreceptor is also an important property. Even with excellent electrophotographic characteristics at low humidity, it is difficult to obtain a stable and clear image on a photoreceptor in which the surface potential of the photoreceptor significantly decreases under high humidity. In addition, in the electrophotographic process for transferring,
Since the photoconductor is usually used repeatedly, the chemical bond of the surface-forming substance is destroyed by corona discharge, and as a result, it reacts with ionized oxygen, ozone, water, nitric oxide, etc., and the surface becomes low in resistance. In many cases, the electrostatic charge retention in humidity is reduced and the sharpness of the image is impaired. In addition, adhered substances such as paper dust often reduce the charge holding ability of the photoconductor and cause image deletion.

Since the surface of the photoreceptor is coated with a resin, the performance of the resin is particularly important, and a resin having excellent durability has been demanded. Recently, as a resin satisfying these requirements, a polycarbonate resin having bisphenol A as a skeleton (hereinafter referred to as bisphenol A type polycarbonate) has been studied as a binder for a surface layer.

First, a polycarbonate resin as an engineering plastic generally has a large surface free energy, and a developer (hereinafter abbreviated as a toner) easily adheres to the surface. When an image is displayed in this situation, a phenomenon in which a large number of white spots appear on the entire black image (hereinafter abbreviated as solid black) is likely to occur.

Secondly, when a photoreceptor is prepared, these binder resin and charge transport material are dissolved in a solvent to be applied and dried to form a film. The resin formed under such conditions has a residual strain stress in its internal structure, and the polycarbonate resin has a particularly strong tendency, and has a drawback that so-called solvent crack is likely to occur. When handling the photoconductor thus created or mounting it on an electrophotographic apparatus, for example, when touched by human hands,
When various oils used in the apparatus are brought into contact with the photoconductor, the photoconductor is likely to be cracked, and when the crack is generated, a defect image appears.

Thirdly, since the coefficient of friction of the surface is large, the amount of abrasion is increased when cleaning is performed with urethane rubber or the like, which makes it difficult to increase the number of durable sheets.

[0022]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a developer for developing an electrostatic charge image and an image forming method which solves the above problems.

That is, it is an object of the present invention to provide a developer for developing an electrostatic charge image and an image forming method which are not easily affected by environmental changes such as temperature and humidity and which have stable triboelectrification under each environment. .

Another object of the present invention is to provide a developer for developing an electrostatic charge image which has clear image characteristics without fog and is excellent in durability stability, and an image forming method.

A further object of the present invention is to provide a developer for developing an electrostatic charge image having excellent fixability and an image forming method.

A further object of the present invention is to provide a developer for developing an electrostatic charge image and an image forming method which are excellent in high resolution, high highlight reproducibility and high fine line reproducibility.

It is another object of the present invention to provide an image forming method which is excellent in transferability and cleaning property and can obtain excellent images satisfactorily even after the endurance of a large number of sheets without causing defective cleaning. To do.

[0028]

Means and Actions for Solving the Problems The present invention achieves the above object by the following constitutions.

The present invention provides a developer for developing an electrostatic charge image containing a toner and a carrier, wherein the toner contains toner particles and titanium oxide, and the toner particles are directly obtained by a suspension polymerization method. The resin component constituting the toner particles has at least one of the molecular weight peaks in the molecular weight range of 5,000 to 50,000 in the molecular weight distribution by GPC. And contains at least one or more polar components, the titanium oxide has an average particle size of 0.01 to 0.2 μm and a degree of hydrophobicity of 20 to 98%, and the carrier is Has an average particle size of 5 to 100 μm and a bulk density of 3.0 g / cm ³ or less,
The magnetic properties of the carrier are: (i) the magnetization intensity (σ ₁₀₀₀ ) at 1000 Oersted after magnetic saturation is 30 to 150 emu / cm ³ ,
(Ii) The strength of magnetization (remanent magnetization: σ _r ) in a magnetic field of 0 Oersted is 25 emu / cm ³ or more, and (ii)
i) the coercive force is less than 300 Oersted, and (i
v) The following formula

[0030]

[Outside 3] (In the formula, σ ₁₀₀₀ and σ ₃₀₀ respectively indicate the strength of magnetization (emu / cm ³ ) at 1000 oersted and 300 oersted after being magnetically saturated.) The present invention relates to a developer for developing a charge image.

In the present invention, a latent image is formed by using an electrophotographic photoreceptor having at least a conductive support and a photosensitive layer having a laminated structure of a charge generation layer and a charge transport layer. In an image forming method in which an image is visualized using a developer and transferred onto a transfer material, a substance having a fluorine atom and / or a silicon atom is present in the surface layer of the electrophotographic photoreceptor, and XPS The ratio of the fluorine atom and the silicon atom to the carbon atom measured is as follows: Fluorine atom / carbon atom (F / C) = 0.01 to 1.00 Silicon atom / carbon atom (Si / C) = 0.03 To 1.00, the developer has a toner and a toner containing titanium oxide and a carrier, and the toner particle has at least a colorant and a toner directly obtained by a suspension polymerization method. Toner particles with resin component Ri, the resin component constituting the toner particles, the molecular weight distribution by GPC, at least one molecular weight peak, molecular weight 5,
In the range of 000 to 50,000 and containing at least one or more polar components, the titanium oxide is
0.01 to 0.2 μm average particle size and 20 to 98%
The carrier has a hydrophobicity of 5 to 100.
The carrier has a mean particle size of μm and a bulk density of 3.0 g / cm ³ or less, and the magnetic properties of the carrier are (i) the magnetic strength at 1000 Oersted after magnetic saturation (σ ₁₀₀₀ ) Is 30 to 150 emu / cm ³ ,
(Ii) The strength of magnetization (remanent magnetization: σ _r ) in a magnetic field of 0 Oersted is 25 emu / cm ³ or more, and (ii)
i) the coercive force is less than 300 Oersted, and (i
v) The following formula

[0032]

[Outside 4] (In the formula, σ ₁₀₀₀ and σ ₃₀₀ respectively indicate the strength of magnetization (emu / cm ³ ) at 1000 oersted and 300 oersted after being magnetically saturated.) It relates to a forming method.

The present invention will be described in detail below.

As a result of intensive studies to solve the above-mentioned problems of the prior art, the present inventors set a carrier magnetic strength of 30 to 150 emu / cm ³ in a magnetic field at the developing pole to form a latent image. It has been found that it is possible to form a clear image that is faithful and free of fog. This is because the strength of the magnetic field at the developing pole is generally about 1000 Oersted, and the strength of the magnetization of the carrier at that time is weak, so that the magnetic brush of the developer becomes short and dense, and the brush becomes soft. Therefore, it is considered that development faithful to the latent image could be achieved. It is considered that such a magnetic brush is short, dense, and soft, so that the development efficiency is improved and higher fidelity development can be performed especially in the development in which an alternating electric field for vibrating the developer is applied. Another advantage of the present invention is that deterioration of image quality can be prevented and high-quality images at the initial stage can be maintained. By using such a carrier with low magnetic force, the developing sleeve is coated with a developer. At this time, the magnetic coupling force of the carrier brush near the regulation member is weak and the brush is soft so that it does not give too much share to the toner, so polar substances on the toner surface are hard to be scraped off, and the initial high image quality is high. It is thought that the image can be maintained for a long time.

Further, as a result of detailed examination, it was found that carrier adhesion is likely to occur at a magnetic field strength of 0 to 300 oersted and does not occur when the carrier magnetization strength at that time is high to some extent. Further, the carrier adhesion depends on the developing bias condition, and particularly when developing by an alternating electric field, the carrier is more easily developed when it has a charge than the DC electric field, and the magnetic force is needed to attract it to the developing sleeve. Is required. Therefore, it is considered that the strength of the magnetization in the magnetic field is required to suppress the carrier adhesion. Therefore, according to the present invention, as shown in the hysteresis curve of FIG. 1, the magnetization intensity σ ₁₀₀₀ at 1000 Oersted is 30 to 150 emu / c.
m ^{3 which} is smaller than the conventional carrier, but 0 to 30
It is considered that by increasing the magnetization intensity at 0 Oersted, it is possible to prevent carrier adhesion while achieving high image quality.

In general, a magnetic material having a large residual magnetization is a magnetic material such as a hard ferrite having a large coercive force such as a so-called permanent magnet, and as described above, the mixing property with the toner due to self-aggregation and the developer. Poor transportability occurs, and the developer carrier is like a rotating magnetic core applicator.
A large and special developing device is required.

The present invention does not use such a general hard magnetic material, but uses a carrier having a coercive force of less than 300 Oersted, so that a small developing device using a fixed magnetic core type developer carrier. But the compatibility with toner,
It is considered that a developer having good developer transportability can be achieved.

The carrier used in the present invention is required to have the following magnetic characteristics of the carrier particles.

(I) It is necessary that the magnetization intensity (σ ₁₀₀₀ ) at 1000 Oersted after magnetic saturation is 30 to 150 emu / cm ³ . To achieve higher image quality, preferably 30 to 12
0 emu / cm ³ is good. When it is higher than 150 emu / cm ^3, the density of the developer brush at the developing pole is not so different from the conventional one, and it becomes difficult to obtain a high quality image as in the present invention. If it is less than ³⁰ emu / cm ³ , the magnetic restraining force at 0 to 300 oersteds is also reduced and carrier adhesion occurs.

(Ii) It is necessary that the strength of magnetization (remanent magnetization) in a magnetic field of 0 oersted is 25 emu / cm ³ or more. When it is less than 25 emu / cm ³ ,
In particular, in a developing system using a large contrast potential for high image quality or using an alternating electric field with a large amplitude, carrier adhesion is likely to occur, and carrier adhesion part causes transfer failure in the transfer process after development. High-quality images cannot be obtained. (Iii) It is necessary that the coercive force is less than 300 Oersted. If the coercive force is 300 oersteds or more, the carrier itself is self-aggregated, resulting in poor mixability with the toner. Particularly, in the developing sleeve including the fixed magnet, the carrier cannot easily move, and the carrier does not easily move on the image sleeve. Therefore, it is difficult to obtain a high-quality image because the transportability is poor and the coated state of the developer is poor.

(Iv) What is important in the present invention is the strength of magnetization in the vicinity of a magnetic field of 0 to 300 Oersted. Therefore, the following formula

[0042]

[Outside 5] [In formula, (sigma) ₁₀₀₀ and (sigma) ₃₀₀ show the intensity | strength of magnetization (emu / cm < ³ >) in 1000 oersted and 300 oersted, respectively after magnetically saturating. ] Is required. Furthermore, this value is preferably 0.30 or less. Here, the hysteresis curve of FIG. 2 will be described. If this value exceeds 0.40, it becomes impossible to achieve both the effect of preventing carrier adhesion while achieving the high image quality of the present invention. That is, if a value that satisfies σ ₁₀₀₀ is taken, high image quality is achieved, but carrier adhesion is likely to occur. Also, if a value that satisfies σ ₃₀₀ is taken, carrier adhesion can be prevented, but σ ₁₀₀₀
As the value of becomes larger, it becomes impossible to obtain a high quality image as in the present invention.

Therefore, the carrier having the magnetic characteristics as described above is unlikely to cause carrier adhesion, and is excellent in high resolution, high highlight reproducibility and high fine line reproducibility.

The measurement of the magnetic characteristics of the carrier in the present invention was carried out by using a DC magnetization BH characteristic automatic recording device BHH-50 manufactured by Riken Denshi Co., Ltd. Since a magnetic material is generally saturated in a magnetic field of 10 kilo Oersted, the saturation magnetization of carriers is set to a value of 10 kilo Oersted in the present invention. Therefore, the magnetic characteristic value is ± 1
A magnetic field of 0 kilo Oersted was created, and it was determined from the hysteresis curve at that time. The magnetic property in the present invention is that after the sample is loosely put in a cylindrical plastic container,
In the magnetized state by applying a magnetic field of 10 kg, strong packing was performed and fixed, and the magnetic characteristics in that state were measured. This was used as the magnetic property of the present invention. The volume of the sample holder at that time was 0.332 cm ³ , and the strength of the magnetization per unit volume was obtained from this.

The carrier particles used in the present invention preferably have an average particle size of 5 to 100 μm, more preferably 20 to 80 μm. If it is less than 5 μm, carrier is likely to adhere to the photosensitive member,
If it exceeds 0 μm, the magnetic brush at the developing pole becomes rough and a high quality image cannot be obtained. In addition, the particle size of the carrier in the present invention is 300 or more randomly extracted by an optical microscope, and the image processing analyzer Luzex3 manufactured by Nireco Corporation is used.
With the horizontal ferret diameter as the carrier particle diameter,
It was measured.

The carrier used in the present invention is 3.0 g.
It is preferable to have a bulk density of / cm ³ or less. 3.0
When g / cm ³ is exceeded, the centrifugal force applied to one carrier is increased due to the rotation of the developing sleeve as compared with the force that the carrier is magnetically held on the sleeve, and carrier scattering easily occurs. The bulk density of the carrier in the present invention was measured according to the method described in JIS Z2504.

The carrier used in the present invention is substantially spherical, and the sphericity is preferably 2 or less. When the sphericity exceeds 2, the fluidity as a developer becomes poor and the shape of the magnetic brush at the developing pole becomes poor, so that a high quality image cannot be obtained. In addition, the sphericity of the carrier in the present invention is measured by randomly extracting 300 or more carriers by a field emission scanning electron microscope S-800 manufactured by Toshiba Corp. and using an image processing analyzer Luzex3 manufactured by Nireco. , And the shape factor derived by the following equation.

[0048]

[Outside 6] MX LNG: maximum diameter of carrier AREA: projected area of carrier Here, the closer SF1 is to 1, the closer it is to a sphere.

The carrier used in the present invention is from 10 ³ to
It is preferable to have a specific resistance of 10 ¹³ Ω · cm. 10
^If it is less than ³ Ω · cm, a developing method in which a bias voltage is applied causes a current to leak from the sleeve to the surface of the photoconductor in the developing area, and a good image cannot be obtained. Also, 10 ¹³
When it exceeds Ω · cm, a charge-up phenomenon is caused under a condition such as low humidity, which causes image deterioration such as density dot, transfer failure, and fog. In addition, in the present invention, the measurement method as shown in FIG. 3 was used to measure the specific resistance of the carrier.
That is, the cell A is filled with a carrier, the lower electrode and the upper electrodes 1 and 2 are arranged so as to be in contact with the filled carrier, a voltage is applied between the electrodes, and a current flowing at that time is measured to obtain a specific resistance. Was used. In the above measuring method, since the carrier is a powder, the filling rate may change, and the specific resistance may change accordingly, which requires caution. The measuring condition of the specific resistance in the present invention is that the contact area S between the filled carrier and the electrode is about 2.3 cm.
² , the thickness d was about 1 mm, the load on the upper electrode 2 was 275 g, and the applied voltage was 100 V.

In FIG. 3, 3 is an insulator, 4 is an ammeter, 5 is a voltmeter, 6 is a constant voltage device, 7 is a carrier, and 8 is a carrier.
Indicates a guide ring.

In order to achieve the above-mentioned magnetic properties, which are the main characteristics of the carrier used in the present invention, a metal oxide magnetic material or an iron-based alloy such as carbon steel, chromium steel, cobalt-chromium steel. It is necessary to use Baicalloy, Alnico alloy, etc. Preferably, Periodic Table IA
Group, Group IIA, Group IIIA, Group IVA, Group VA, VIA
Group, IB group, IIB group, IVB group, VB group, VIB group,
Ferrite particles containing at least one element selected from the group consisting of VIIB group and VIII group and containing less than 1% by weight of other elements are preferable. If other elements are included, it becomes difficult to obtain a carrier having the desired magnetic characteristics used in the present invention, and the resistance tends to decrease, which is not preferable.

The carrier used in the present invention is a spinel structure single phase, a magnet planvite structure single phase, a composite phase having at least a spinel structure or a magnet planvite structure, and a composite phase having a spinel structure and a magnet planvite structure. At this time, the molar ratio of the spinel phase and the magnetplumbite phase is preferably 1: 1 to 10: 1. Further, it is preferable that the magnetic particles having the spinel structure and the magnet prambite structure do not react much with each other.

By taking such a composition form, the magnetization intensity (σ ₁₀₀₀ ) at 1000 oersted after magnetic saturation is 30 to 150 emu / cm ³ , and the residual magnetization σ _r is 25 emu / cm ^3. As described above, it is possible to obtain a carrier having magnetic properties with a coercive force of less than 300 Oersted.

In the present invention, the crystals constituting the carrier were measured by the X-ray diffraction method and the fluorescent X-ray.

The carrier used in the present invention is a sintering method,
It is possible to manufacture by a manufacturing method such as atomizing method,
If necessary, the carrier having the above-mentioned specific magnetic characteristics can be produced by a method of mixing and sintering two or more kinds of crystal fine powders.

When the carrier used in the present invention is used after being magnetically saturated, it becomes easy to achieve the characteristic magnetic characteristics of the present invention. As a method of magnetic saturation, there is a method of exposing carrier particles to a magnetic field of ± 10 kilo Oersted with a DC electromagnet.

The carrier of the present invention can be used by coating the surface of carrier particles with an arbitrary resin, if necessary, in order to control the above-mentioned specific resistance and improve durability. As the coat resin, a known appropriate resin can be used. For example, an acrylic resin,
Fluorine-based resin, silicon-based resin, epoxy-based resin and the like can be mentioned.

On the other hand, in order to obtain a toner having excellent fixability, which is one of the objects of the present invention, the resin component constituting the toner particles has a molecular weight of 5,000 at least one of the peaks of the molecular weight distribution by GPC. It was found that it is effective to contain at least one or more polar components in the range of ˜50,000.

That is, by adding a resin having a good affinity with paper, the adhesiveness with paper is further increased.

It has been found that the above-mentioned toner particles are toner particles directly obtained by the suspension polymerization method, which is preferable as a means for achieving the object of the present invention.

It is considered that the polar component internally added is more likely to be present on the surface of the toner particles when produced in an aqueous system, so that one of the objects of the present invention can be achieved more effectively.

When at least one of the peaks of the molecular weight distribution by GPC of the resin component constituting the toner particles in the present invention exists in the molecular weight range of 5,000 to 50,000, low temperature fixability can be exhibited.

When the peak of the molecular weight distribution in GPC of the resin component that achieves the toner particles is less than 5,000, the blocking resistance becomes poor.
There are no peaks in the range specified by the present invention and 50,000
When the peak exceeds the range, the low temperature fixability becomes poor.

Further, preferably, the molecular weight is 100,00.
When the content of 0 or less is 50% or less, good fixability can be exhibited.

In the present invention, the molecular weight distribution of the chromatogram by GPC using THF (tetrahydrofuran), which is a resin component constituting the toner particles, as a solvent is measured under the following conditions.

The column was stabilized in a heat chamber at 40 ° C., and THF as a solvent was flowed through the column at this temperature at a flow rate of 1 ml / min to prepare a THF sample solution of about 100 μm.
l Inject and measure. When measuring the molecular weight of a sample,
The molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of the calibration curve prepared from several kinds of monodisperse polystyrene standard samples and the count number. As a standard polystyrene sample for preparing a calibration curve, for example, a standard polystyrene sample having a molecular weight of about 10 ² to 10 ⁷ manufactured by Tosoh or Showa Denko is used, and it is suitable to use a standard polystyrene sample of at least about 10 points. is there. In addition, the detector is RI (refractive index)
Use a detector. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns, for example, Shodex GPC KF-80 manufactured by Showa Denko KK
1, 802, 803, 804, 805, 806, 80
Combination of 7,800P and TSKge manufactured by Tosoh Corporation
1 G1000H (H _XL ), G2000H (H _XL ), G
3000H (H _XL ), G4000H (H _XL ), G500
0H (H _XL ), G6000H (H _XL ), G7000H
(H _XL ), a combination of TSKguard colnmn can be mentioned.

The sample is manufactured as follows. Put the sample in THF, leave it for several hours, and shake it well for TH
Mix well with F (until there is no union of the samples), then 1 more
Let stand for at least 2 hours. At this time, the leaving time in THF should be 24 hours or more. After that, a sample that has passed through a sample processing filter (pore size 0.45 to 0.5 μm, for example, Maisori Disc H-25-5 Tosoh Co., Ltd., Excicro Disc 25CR Gelman Science Japan Co., Ltd.) can be used. GPC
Of the sample. The sample concentration is 0.5 to 5 for the resin component.
Adjust to mg / ml.

Further, in the toner of the present invention, it is preferable to use titanium oxide as an additive for toner particles. The reason is considered as follows. That is, the polar substance is apt to be unevenly distributed on the surface of the polymerized toner particles as described above. For this reason, the hygroscopicity fluctuates as the environment fluctuates, and the environmental stability of the charging property is still insufficient.

On the other hand, the titanium oxide fine particles used in the present invention have a substantially neutral chargeability as compared with the hydrophobic silica, so that a constant fluidity can be obtained without being affected by the charge of the toner particles. it is conceivable that.

The titanium oxide used in the present invention preferably has a hydrophobicity of 20 to 98%, preferably 30 to 90%, more preferably 40 to 80%.

If the degree of hydrophobicity is less than 20%, the amount of charge is greatly reduced by leaving it in a high humidity for a long period of time, a mechanism for promoting charge on the hardware side is required, the apparatus becomes complicated, and the degree of hydrophobicity is increased. If it exceeds 98%, it becomes difficult to control the charge of titanium oxide itself, and as a result, the toner is charged up under low humidity.

The average particle size of the titanium oxide is preferably 0.01 to 0.2 μm from the viewpoint of imparting fluidity. If the average particle size is larger than 0.2 μm, toner charging due to poor fluidity becomes uneven, resulting in toner scattering and fog. If the average particle size is smaller than 0.01 μm, the toner particles are likely to be embedded on the surface of the toner, and the toner deteriorates quickly, resulting in a decrease in durability. As a means for rendering the titanium oxide hydrophobic, it is preferable to treat it with a coupling agent.

Examples of the coupling agent that can be used in the present invention include silane coupling agents and titanium coupling agents.
Any material that can be hydrophobized can be used. Particularly preferably used is a silane coupling agent,
A compound represented by the following general formula R _m SiY _n R: an alkooxy group m: an integer of 1 to 3 Y: an alkyl group, a hydrocarbon group containing a vinyl group, a glycidoxy group, and a methacryl group, an integer of n: 1 to 3, is preferable. For example, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, methyltrimethoxysilane, methyltriethoxysilane, isobutyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, trimethyl. Examples thereof include methoxysilane, hydroxypropyritrimethoxysilane, phenyltrimethoxysilane, n-hexadecyltrimethoxysilane, and n-octadecyltrimethoxysilane.

More preferably, one represented by the following general formula CaH _{2a + 1} -Si (OC _b H _{2b + 1} ) ₃ a: an integer of 4 to 12 and an integer of b: 1 to 3 is preferable.

If a in the above general formula is smaller than 4,
Although the treatment is easy, it becomes difficult to achieve sufficient hydrophobicity. When a is larger than 12, the hydrophobicity is sufficient, but the titanium oxide particles are often coalesced with each other and the fluidity-imparting ability is deteriorated. .

If b in the above general formula is larger than 3, the reactivity is lowered and the hydrophobic property is not sufficiently achieved.

Therefore, in the above general formula, a is 4 to 1
2, preferably 4-8, and b is 1-3, preferably 1-2.

The method for measuring the degree of hydrophobicity in the present invention is shown below.

Hydrophobicity Measurement Method The methanol titration test is an experimental test for confirming the hydrophobization degree of titanium oxide fine powder having a hydrophobized surface.

The "methanol titration test" defined in this specification for evaluating the hydrophobicity of the treated titanium oxide fine powder is performed as follows. Titanium oxide fine powder 0.2 g was placed in a 250 ml Erlenmeyer flask with 50 m of water.
Add to l. Methanol is titrated from the burette until the total amount of titanium oxide is wet. At this time, the solution in the flask is constantly stirred with a magnetic stirrer. The end point is observed by suspending the total amount of fine titanium oxide powder in the liquid, and the degree of hydrophobization is expressed as the percentage of methanol in the liquid mixture of methanol and water when the end point is reached.

Further, in the present invention, the treated titanium oxide has a light transmittance of 40% or more at a light length of 400 nm when dispersed in an ethanol solvent at a solid content concentration of 0.1%. Is also one of the features.

That is, although the titanium oxide used in the present invention has a very small primary particle diameter of 0.01 to 0.2 μm, it does not always mean that the primary particles are mixed with the toner particles. The particles may not be dispersed in the state of 2) but may exist in the state of secondary particles. Therefore, no matter how small the primary particle diameter is, if the effective diameter that behaves as secondary particles is large, it will be difficult to obtain the effects of the present invention sufficiently. However, the lower limit wavelength of the visible region is 400 mm when dispersed in the liquid phase.
The higher the light transmittance in, the smaller the secondary particle diameter, and the better results such as the sharpness of the projected image of the fluidity imparting ability OHP can be expected.

The method of measuring the transmittance in the present invention is shown below.

Method of measuring transmittance 1. Sample 0.10 g Alkyd resin 13.20 * 1 Melamine resin 3.30 * 2 Thinner 3.50 * 3 Glass media 50.00 * 1 Beckozol 1323-60- manufactured by Dainippon Ink and Chemicals
EL * 2 Super Beckamine J-820 manufactured by Dainippon Ink and Chemicals, Inc.
-60 * 3 Kansai Paint Co., Ltd. Amylak Thinner The above composition is sampled in a 150 cc mayonnaise bottle and dispersed for 1 hour in a Red Devil paint conditioner. 2. After the dispersion is completed, the PET film is coated with a 2 mil doctor blade. 3.2. Is heated at 120 ° C. for 10 minutes to perform baking. 4.3. The sheet is measured with a U-BEST 50 manufactured by JASCO Corporation in the range of 320 to 800 nm to compare the transmittance.

In the present invention, the following additives may be used in addition to the above titanium oxide fine particles.

As an additive for imparting various toner characteristics, from the viewpoint of durability in the toner or when it is added to the toner, the particle diameter is 1/10 or less of the volume average diameter of the toner particles. Is preferred. What is the particle size of this additive?
It means the average particle size of the toner particles obtained by observing the surface thereof with an electron microscope. As the additives for imparting these characteristics, for example, the following ones are used.

1) Flowability-imparting agent: metal oxide (silicon oxide, aluminum oxide, etc.), carbon black, carbon fluoride, etc. Those subjected to a hydrophobic treatment are more preferable.

2) Abrasive: metal oxide (strontium titanate, cerium oxide, aluminum oxide, magnesium oxide, chromium oxide, etc.), nitride (silicon nitride, etc.), carbide (silicon carbide, etc.), metal salt (calcium sulfate, Barium sulfate, calcium carbonate, etc.) etc.

3) Lubricants: Fluorine-based resin powders (vinylidene fluoride, polytetrafluoroethylene, etc.), fatty acid metal salts (zinc stearate, calcium stearate, etc.), etc.

4) Charge controllable particles: metal oxides (tin oxide, zinc oxide, silicon oxide, aluminum oxide, etc.)
Carbon black etc.

These additives are used in an amount of 0.1 to 10 parts by weight, preferably 100 parts by weight of the toner particles.
0.1-5 parts by weight are used. These additives may be used alone or in combination.

In the toner used in the present invention, the polar component contained in the resin component constituting the toner particles includes a polymer of nitrogen-containing monomer such as dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate or styrene Copolymers with saturated carboxylic acid esters, etc., nitrile monomers such as acrylonitrile, halogen-containing monomers such as vinyl chloride, unsaturated carboxylic acids such as acrylic acid and methacrylic acid, and other unsaturated dibasic acids. Examples thereof include unsaturated dibasic acid anhydrides, polymers such as nitro monomers, copolymers with styrene monomers, polyesters, epoxy resins and the like.

The following method is used as a method for incorporating the polar component into the toner particles.

In the polymerization method toner particles, the above polar component is added as a polymer or copolymer by dissolving it in another monomer component and polymerizing, or by adding the above polar component as a monomer. The method of adding by mixing with the monomer component and polymerizing.

Other polymerizable monomers usable in the present invention include styrene.o as the polymerizable monomer usable in the toner particles.
-Styrene monomers such as methyl styrene, m-methyl styrene, p-methyl styrene, p-methoxy styrene, p-ethyl styrene, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, etc.
Acrylic esters such as n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, etc. Monomers of methacrylates such as n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, etc. Can be mentioned. These monomers alone,
Alternatively, they may be mixed and used. Among the above-mentioned monomers, it is preferable to use styrene or a styrene derivative alone or in combination with other monomers, from the viewpoint of developing characteristics and durability of the toner.

As the coloring agent used in the present invention, known coloring agents can be used. Examples thereof include carbon black, iron black, C.I. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I. I. Mordant Red 30, C.I.
I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Acid Blue 9, C.I. I. Acid Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Mordant Blue 7, C.I. I.
Direct Green 6, C.I. I. Basic Green 4, C.I. I. Dyes such as basic green 6, yellow lead, cadmium yellow, mineral fast yellow, navel yellow, naphthol yellow S, Hansa yellow G, permanent yellow NCG, tartrazine lake, molybdenum orange, permanent orange GT
R, benzidine orange G, cadmium red, permanent red 4R, watching ledge calcium salt,
Brilliankamine 3B, Fast Violet B, Methyl Violet Lake, Navy Blue, Cobalt Blue, Alkali Blue Lake, Victoria Blue Lake, Quinacridone, Rhodamine Lake, Phthalocyanine Blue, Fast Sky Blue, Pigment Green B, Malachite Green Lake, Final Yellow Green G etc. There is a pigment. In the present invention, since the toner is obtained by using the polymerization method, it is necessary to pay attention to the polymerization inhibitory property and the water phase transfer property of the colorant. Preferably, the surface modification, for example, the hydrophobic property of a substance that does not inhibit the polymerization is used. It is better to apply chemical treatment. In particular, since many dyes and carbon black have a polymerization inhibitory property, caution is required when using them. A preferred method for surface-treating a dye system is a method of polymerizing a polymerizable monomer in the presence of these dyes in advance, and the obtained colored polymer is added to the monomer system. In addition to carbon black, the carbon black may be treated with a substance that reacts with the surface functional groups of carbon black, such as polyorganosiloxane.

When the toner is used as a magnetic toner, it may contain magnetic powder. As such magnetic powder, a substance that is magnetized when placed in a magnetic field is used.
There are powders of ferromagnetic metals such as iron, cobalt and nickel, and compounds such as magnetite and ferrite. In particular, in the present invention, in order to obtain a toner by using a polymerization method, it is necessary to pay attention to the polymerization inhibitory property and the water phase transfer property of the magnetic substance, and preferably surface modification, for example, a substance without polymerization inhibition It is better to give a hydrophobic treatment by.

In the present invention, for the purpose of improving releasability at the time of heat roll fixing, waxes generally used as a releasing agent such as a hydrocarbon compound may be blended in the toner particles. Examples of waxes used in the present invention include paraffin / polyolefin waxes and modified products thereof, such as oxides and graft-treated products, higher fatty acids, metal salts thereof, and amide waxes.
These waxes have a softening point of 40 to 130 ° C., preferably 50 to 120 ° C. according to the ring and ball method (JIS K 2531).
And a softening point of 40 ° C. or less is insufficient in blocking resistance and shape retention of the toner.
At 0 ° C or higher, the effect of releasability becomes insufficient.

These release agents may be used alone or in combination, and the addition amount is preferably 0.1 to 50% by weight.

In the present invention, it is desirable to add a charge control agent to the toner material for the purpose of controlling the chargeability of the toner. As these charge control agents, among known ones, those having almost no polymerization inhibitory property / water phase transfer property are used. For example, as positive charge control agents, nigrosine dyes, triphenylmethane dyes, quaternary ammonium salts, guanidines are used. Derivatives, imidazole derivatives, amine-based and polyamine-based compounds, and the like. As a negative charge control agent, metal-containing salicylic acid-based compounds, metal-containing monoazo-based dye compounds, urea derivatives, styrene-acrylic acid copolymers, styrene-methacryl Examples thereof include acid copolymers.

The addition amount of these charge control agents is 0.
1 to 10% by weight is preferable.

As the polymerization initiator, any suitable polymerization initiator, for example, 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1, 1'-azobis (cyclohexane-1-
Carbonitrile), 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile and other azo or diazo polymerization initiators, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, Examples thereof include peroxide-based polymerization initiators such as cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide and lauroyl peroxide. These polymerization initiators are preferably added in an amount of 0.5 to 20% by weight of the polymerizable monomer, and may be used alone or in combination.

In the present invention, in order to control the molecular weight, known crosslinking agents and chain transfer agents may be added, and the preferable addition amount is 0.001 to 15% by weight.

Any suitable stabilizer is used in the dispersion medium used in the present invention. For example, as an inorganic compound, tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate. -Bentonite, silica, alumina, etc. may be mentioned. As an organic compound, polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and its salt, starch and the like can be dispersed in an aqueous phase and used.
These stabilizers are based on 100 parts of the polymerizable monomer,
It is preferred to use 0.2 to 20 parts by weight.

When an inorganic compound is used among these stabilizers, a commercially available product may be used as it is, but the inorganic compound may be produced in a dispersion medium in order to obtain fine particles. For example, in the case of tricalcium phosphate, it is advisable to mix the sodium phosphate aqueous solution and the calcium chloride aqueous solution under high stirring.

Due to the fine dispersion of these stabilizers,
0.001-0.1 parts by weight of surfactant may be used. This is for promoting the intended action of the dispersion stabilizer, and specific examples thereof include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, and lauric acid. Examples include sodium, potassium stearate, calcium oleate, and the like.

The polymerized toner particles used in the present invention can be obtained by the following method. That is, a releasing agent, a colorant, a charge control agent, a polymerization initiator and other additives are added to the polymerizable monomer, and a homogenizer and an ultrasonic disperser are used to uniformly dissolve or disperse the monomer system. It is dispersed in an aqueous phase containing a dispersion stabilizer by a usual stirrer, a homomixer / homogenizer or the like. Granulation is preferably performed by adjusting the stirring speed and time so that the monomer droplets have a desired toner particle size, generally 30 μm or less. After that, stirring may be performed to the extent that the particle state is maintained and the particles are prevented from settling by the action of the dispersion stabilizer. Polymerization temperature is 40 ° C or higher, generally 50 to 90 ° C
Polymerization is performed by setting the temperature to. In addition, the temperature may be raised in the latter half of the polymerization reaction, and further in the latter half of the reaction or the end of the reaction in order to remove unreacted polymerizable monomers and byproducts that may cause odor during toner fixing. The aqueous medium may be partially distilled off later. After the reaction is completed, the produced toner particles are collected by washing and filtration and dried. In the suspension polymerization method, it is usually preferable to use 300 to 3000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the monomer system.

The image forming method of the present invention forms an image by forming a latent image using an electrophotographic photosensitive member, visualizing the latent image using a developer, and transferring and forming the latent image on a transfer material. To do.

As the developer used in this image forming method, the above-mentioned developer for developing electrostatic image can be used.

Further, the electrophotographic photosensitive member used in the image forming method of the present invention preferably has at least a conductive support and a photosensitive layer having a laminated structure of a charge generating layer and a charge transporting layer.

The surface layer of this electrophotographic photosensitive member, that is,
When the protective layer is provided on the charge transport layer or the photosensitive layer, a substance having a fluorine atom and / or a silicon atom is present in the protective layer, and the fluorine atom and the silicon atom and the carbon atom are measured by XPS measurement. When the ratio satisfies the following conditions: fluorine atom / carbon atom (F / C) = 0.01 to 1.00 silicon atom / carbon atom (Si / C) = 0.03 to 1.00, higher image quality is achieved. I found that an image was obtained.

The reason for defining F / C and Si / C here is that when the surface of the photoreceptor is combined with the present invention,
It is configured to achieve the object of the present invention.

That is, the fluorine atom and the silicon atom reduce the surface energy of the photoconductor, and the transferability is improved.
Also, the adhesiveness is reduced. On the other hand, the presence of carbon atoms increases the surface energy. The present inventors have found that by defining this ratio, a toner composition having a large amount of polar components on the toner surface as in the present invention and having a strong adhesive force can have a structure with good transferability and no cleaning failure. .

Here, the F / C and Si / C of the surface layer of the photoconductor are 0.01 with respect to the toner used in the present invention.
And less than 0.03, the surface energy of the photoconductor is high, deteriorating the transferability of the toner, and when F / C and Si / C exceed 1.00 respectively, the friction coefficient with the cleaning member decreases, and conversely. Toner slips through and cleaning failure occurs.

An even more preferable structure is that the surface layer of the electrophotographic photosensitive member contains a polycarbonate, and even more preferably, the polycarbonate is synthesized from an asymmetric diol.

As a result, an electrophotographic photosensitive member having excellent durability and good productivity can be obtained. Further, as a preferable constitution, it is preferable that a protective layer is provided on the photosensitive layer of the electrophotosensitive material and that the protective layer contains polycarbonate.

As a result, further stability of durability characteristics is produced.

Further, as a more preferable constitution for achieving the object of the present invention, X of the surface layer of the electrophotographic photosensitive member of the present invention is preferable.
The ratio of fluorine atoms and / or silicon atoms to oxygen atoms measured by PS is as follows: Fluorine atom / oxygen atom (F / O) = 0.01 or more Silicon atom / oxygen atom (Si / O) = 0.03 or more It is preferable to be satisfied.

By defining the amount of oxygen atoms with respect to fluorine atoms and silicon atoms as described above, the adhesion to the toner containing the resin having the polar component of the present invention can be more preferably controlled.

The XPS measuring method for the surface of the electrophotographic photosensitive member according to the present invention will be described below.

The XPS measuring device is ES manufactured by VG.
It was performed using a CALAB200-X type, X-ray photoelectron spectrometer.

The measurement conditions were as follows: X-ray source Mg Kα (300 W) analysis area 2 × 3 mm.

The components used in the present invention will be specifically exemplified below.

The constitution of the electrophotographic photosensitive member used in the present invention will be shown.

The photoconductor used in the present invention has a photosensitive layer having a laminated structure having a charge generation layer and a charge transport layer on a conductive substrate. Further, in the present invention, a structure in which a protective layer is provided on the charge transport layer may be used.

The present invention is characterized in that the charge transport layer and / or the protective layer serving as the surface layer of the photoreceptor contains a fluorine compound and / or a silicon compound.

Furthermore, as a means for achieving the object of the present invention more effectively, it is preferable that the charge transport layer and / or the protective layer contain a polycarbonate.

Further, in the present invention, it is preferable that the polycarbonate contains a polycarbonate synthesized by using an asymmetric diol.

The materials used for the photoconductor of the present invention are exemplified below.

Specific examples of the fluorine-based compound include known fluorine-based resins such as tetrafluoroethylene, trifluoroethylene chloride, tetrafluoroethylene hexafluoropropylene, vinyl fluoride, vinylidene fluoride and difluoride. One or more of ethylene dichloride and copolymers thereof are appropriately selected.

Carbon fluoride or the like can also be used.

In the present invention, a block containing a fluorine-containing segment synthesized from polymerization or copolymerization with a fluorine-based polymerizable monomer or a non-fluorine-based polymerizable monomer,
The graft polymer, surfactant, macromonomer and the like can be used alone or in combination with the above-mentioned fluororesin.

In particular, the combined use with a fluorine-based graft polymer having continuous fluorine-based segments is preferable from the viewpoint of facilitating the dispersion of the fluorine-based resin and the control of the surface F / C ratio which is a feature of the present invention.

Preferred specific examples of the above-mentioned fluorine-based polymerizable monomer are shown below, but the range of compounds that can be used is not limited to the range given here.

[0135]

[Outside 7] (In the above compounds, R ₁ represents a hydrogen atom, a halogen atom or a methyl group, R ₂ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or a nitrile group, and may be a combination of several kinds thereof, and k is 1 to 1). An integer of 4, m is 1 to 5
Is an integer, k + m = 5, and Rf is at least 1
An alkyl group having one or more fluorine atoms is shown. ) Non-fluorine-based polymerizable monomers include low molecular weight linear unsaturated hydrocarbons, vinyl halides, organic acid vinyl esters, vinyl aromatic compounds, acrylic acid and methacrylic acid esters, N-vinyl compounds, vinyl Silicon compounds,
One or more of maleic anhydride, maleic acid and fumaric acid esters can be used, and the formed charge transport layer and / or protective layer to which the formed fluorine-based graft polymer is added can be used. What is compatible with the resin layer,
Alternatively, it is preferable to select those having a similar structure and having a little affinity between them even if they are not completely compatible with each other.

Specific examples of the silicon compound include monomethylsiloxane three-dimensional crosslinked products and dimethylsiloxane-
A monomethylsiloxane three-dimensional crosslinked product, an ultrahigh molecular weight polydimethylsiloxane, a block polymer containing a polydimethylsiloxane segment, a graft polymer, a surfactant, a macromonomer, a terminal-modified polydimethylsiloxane, etc. are used. In the case of a three-dimensional crosslinked product, the particle size used in the form of fine particles can be used in the range of 0.01 to 5 μm. In the case of a polydimethylsiloxane compound, its molecular weight can be used in the range of 3000-5,000,000. The fine particles are dispersed as a photosensitive layer composition together with a binder resin. As a dispersing method, a sand mill, a ball mill, a roll mill, a homogenizer, a nanomizer, a paint shaker, an ultrasonic wave or the like is used. At the time of dispersion, it is preferable to use the above-mentioned graft, block polymer or surfactant as a dispersion aid, and it is also preferable to use them in combination for controlling the Si / C ratio which is a feature of the present invention.

The aromatic hydrocarbon solvent or the halogenated aromatic hydrocarbon solvent-soluble polycarbonate used in the charge transport layer and / or the protective layer of the present invention can be obtained by reducing the crystallinity. . Specifically, for example, 1) bisphenol A and one or two or more asymmetric diol compounds 2) One or two or more asymmetric diol compounds, and a general polycarbonate synthesis method such as a phosgene method Can be obtained by It can also be obtained by using a diol compound having a side chain with a substituent having 3 or more carbon atoms.

Typical specific examples of the asymmetric diol compound used in the present invention are shown below, but the present invention is not limited thereto.

[0139]

[Outside 8]

[0140]

[Outside 9]

[0141]

[Outside 10]

[0142]

[Outside 11]

[0143]

[Outside 12]

The ratio of the asymmetric diol compound in the above-mentioned copolymerized polycarbonate with bisphenol A is preferably 20% by weight or more, and particularly preferably 50% by weight or more in the diol compound. 20% by weight of asymmetric diol compound
When it is below, the solubility in the aromatic hydrocarbon solvent or the halogenated aromatic hydrocarbon solvent becomes insufficient, and the temporal stability of the coating solution also deteriorates. The solubility of the polycarbonate soluble in the above-mentioned aromatic hydrocarbon solvent or halogenated aromatic hydrocarbon solvent (the number of grams of polycarbonate in 100 g of the solution at a temperature of 25 ° C.) is 1 g or more,
Particularly, 5 g or more is preferable. When the solubility is 1 g or less,
For example, when the coating solution for the charge transport layer is prepared, the viscosity of the coating solution is too low to obtain an appropriate film thickness required for the charge transport layer.

The effect of the polycarbonate used in the present invention can be enhanced particularly when it is used as a binder resin for the charge generation layer or the charge transport layer.

Examples of the aromatic hydrocarbon solvent include benzene, toluene, xylene and the like, and examples of the halogenated aromatic hydrocarbon solvent include monochlorobenzene, dichlorobenzene and the like.

When the electrophotographic photosensitive member used in the present invention is manufactured, a metal such as aluminum or stainless steel, a cylindrical cylinder such as paper or plastic, or a film is used as the conductive substrate. On top of these substrates,
An undercoat layer (adhesive layer) having a barrier function and an undercoat function can be provided.

The subbing layer is for improving the adhesion of the photosensitive layer, improving the coating property, protecting the substrate, covering defects on the substrate, improving the charge injection property from the substrate, protecting the photosensitive layer against electrical breakdown, etc. It is formed. Examples of the material for the undercoat layer include polyvinyl alcohol, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, casein, polyamide,
Copolymerized nylon, glue, gelatin, etc. are known. These are dissolved in a solvent suitable for each and coated on the substrate. The film thickness is about 0.2 to 2 μ.

In the function-separated type photoreceptor, selenium-tellurium, pyrylium, thiapyrylium dyes, phthalocyanine pigments, anthanthrone pigments, dibenzpyrenequinone pigments, pyranthrone pigments, trisazo pigments, diazo pigments, azo pigments are used as charge generating substances. , Indigo pigment,
A quinacridone pigment, an asymmetric quinocyanine, a quinocyanine, or amorphous silicon described in JP-A No. 54-143645 can be used, and as the charge transport material, pyrene, N-ethylcarbazole, N-isopropylcarbazole, N- Methyl-N-phenylhydrazino-3-methylidene-9-ethylcarbazole, N,
N-diphenylhydrazino-3-methylidene-9-ethylcarbazole, N, N-diphenylhydrazino-3-
Methylidene-10-ethylphenothiazine, N, N-diphenylhydrazino-3-methylidene-10-ethylphenoxazine, P-diethylaminobenzaldehyde-
N, N-diphenylhydrazone, P-diethylaminobenzaldehyde-N-α-naphthyl-N-phenylhydrazone, P-pyrrolidinobenzaldehyde-N, N-diphenylhydrazone, 1,3,3-tramethylindolenine-ω-aldehyde Hydrazones such as -N, N-diphenylhydrazone, P-diethylbenzaldehyde-3-methylbenzthiazolinone-2-hydrazone, 2,
5-bis (P-diethylaminophenyl) -1,3,4
-Oxadiazole, 1-phenyl-3- (P-diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, 1- [quinolyl (2)]-3- (P-
Diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, 1 [pyridyl (2)]-3-
(P-diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, 1- [6-methoxy-pyridyl (2)]-3- (P-diethylaminostyryl)
-5- (P-diethylaminophenyl) pyrazoline, 1
-[Pyridyl (3)]-3- (P-diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, 1- [lepidyl (2)]-3- (P-diethylaminostyryl) -5- (P- Diethylaminophenyl) pyrazolin, 1- [pyridyl (2)]-3-3 (P-diethylaminostyryl) -4-methyl-5- (P-diethylaminophenyl) pyrazolin, 1- [pyridyl (2)]-3- ( α-methyl-P-diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, 1-phenyl-3- (P-diethylaminostyryl) -4-methyl-5- (P-diethylaminophenyl) pyrazoline, 1-phenyl -3- (α-benzyl-
Pyrazolines such as P-diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline and spiropyrazoline, 2- (P-diethylaminostyryl) -6-
Oxazole compounds such as diethylaminobenzoxazole, 2- (P-diethylaminophenyl) -4- (P-dimethylaminophenyl) -5- (2-chlorophenyl) oxazole, 2- (P-diethylaminostyryl) -6-diethylaminobenzo Thiazole-based compounds such as thiazoles, triarylmethane-based compounds such as bis (4-diethylamino-2-methylphenyl) -phenylmethane, 1,1-bis (4-N, N-diethylamino-)
Polyarylalkanes such as 2-methylphenyl) heptane and 1,1,2,2-tetrakis- (4-N, N-dimethylamino-2-methylphenyl) ethane can be used.

The charge generation layer contains the charge generation pigment described above.
Disperse well with 3 to 4 times the amount of binder resin and solvent by a method such as homogenizer, ultrasonic wave, ball mill, vibrating ball mill, sand mill, attritor, roll mill,
It is formed by applying and drying. Its thickness is 0.1-1μ
It is a degree.

When the above-mentioned polycarbonate resin is used for the charge generation layer, is the charge generation substance dissolved with the polycarbonate in an aromatic hydrocarbon solvent or a halogenated aromatic hydrocarbon solvent alone or in a mixed solvent thereof? ,
It is formed by applying a coating liquid obtained by dispersing a charge generating substance to a solution obtained by dissolving the above polycarbonate resin in the above solvent. The proportion of the charge generating material in the charge generating layer can be 30% by weight or more, preferably 80% by weight or more. Toluene, xylene or monochlorobenzene are particularly useful as the solvent. As a method of applying this coating solution, for example, a dip coating method, a spray coating method, a spinner coating method, a curtain coating method or the like can be used.

When the above-mentioned polycarbonate resin is used for the charge-transporting layer, the charge-transporting substance and the above-mentioned polycarbonate are used as the above-mentioned aromatic hydrocarbon solvent or halogenated aromatic hydrocarbon solvent alone or as a mixed solvent thereof. It is obtained by applying a coating solution prepared by dissolving. The mixing ratio of the charge transport material and the above-mentioned polycarbonate resin used as the binder is about 2: 1 to 1: 2 by weight. Toluene, xylene or monochlorobenzene are particularly useful as the solvent.

As a method for applying this solution, for example, a dip coating method, a spray coating method, a spinner coating method, a curtain coating method and the like are known. The dip coating method is the best for efficient and accurate mass production of electrophotographic photoreceptors, and the pot life in the dip coating method can be greatly improved by using the above-mentioned polycarbonate. The productivity of manufacturing using the coating method can be significantly improved. After coating and forming the charge transport layer, blast drying or static drying is performed at a temperature of 10 ° C. to 200 ° C., preferably 20 ° C. to 150 ° C. for 5 minutes to 5 hours, preferably 10 minutes to 2 hours, A 20μ charge transport layer is obtained.

[0154]

EXAMPLES The present invention will be specifically described below with reference to examples. These do not limit the invention in any way.

[Production Example A of Polymerized Toner Particles] To 710 g of ion-exchanged water, 450 g of 0.1 M Na ₃ PO ₄ aqueous solution was added.
Was charged and heated to 60 ° C., and then stirred at 12000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo). 68 g of 1.0 M-CaCl ₂ aqueous solution was gradually added to this to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

Styrene 180 g 2-Ethylhexyl acrylate 20 g Phthalocyanine pigment 10 g Di-t-butylsalicylic acid metal compound 1 g Styrene-methacrylic acid copolymer (molar ratio 95: 5, M
_W 50,000) 10g Paraffin wax 40g

The above formulation was heated to 60 ° C., and 12000 rpm was obtained using a TK homomixer (made by Tokushu Kika Kogyo).
Were uniformly dissolved and dispersed. In addition to this, the polymerization initiator 2,
2'-azobis (2,4-dimethylvaleronitrile) 1
0 g was dissolved to prepare a polymerizable monomer composition.

The above polymerizable monomer composition was added to the above aqueous medium and stirred at 60 ° C. under N ₂ atmosphere with a TK type homomixer at 10,000 rpm for 20 minutes to obtain the polymerizable monomer composition. Was granulated. Then, while stirring with a paddle stirring blade, the temperature was raised to 80 ° C. and the reaction was performed for 10 hours.

After completion of the polymerization reaction, part of the aqueous medium was distilled off under reduced pressure, the mixture was cooled, hydrochloric acid was added to dissolve calcium phosphate, and the mixture was filtered, washed with water and dried to give a weight average diameter of about 8 μm.
m sharp colored suspended particles A (toner particles A) were obtained.

[Polymerized Toner Particle Production Example B] Toner particle B was obtained in the same manner as Polymerized toner particle Production Example A, except that the phthalocyanine pigment used in Polymerized toner particle Production Example A was changed to carbon black.

[Polymerized Toner Particle Production Examples C and D] Toner particles C and D having different molecular weight peaks in the molecular weight distribution were obtained by adjusting the amount of polymerization initiator and the polymerization temperature used in Polymerized toner particle Production Example A. .

Table 1 shows the molecular weight peaks of the toner particles A to D obtained in the polymerized toner particle production examples A to D.

[0163]

[Table 1] Regarding the toner particles C, some blocking occurred during the manufacturing process during drying, which was not suitable for evaluation.

[Carrier Production Example A] The molar ratio of Fe ₂ O
₃ = 60 mol%, CuO = 20 mol%, ZnO = 20 mol%, while Fe ₂ O ₃ = 82 mol%, SrCO ₂ = 10 mol%, ZnO = 8 mol% Were weighed and mixed using a ball mill. After calcination of each of these, pulverization is performed with a ball mill, the above formulations are mixed at a ratio of 2: 1 respectively, polyvinyl alcohol, a defoaming agent and a dispersant are added to form a slurry, and granulation drying is performed using a spray dryer. Then, sintering was performed. Further classification results in an average particle size of 55 μm
To obtain carrier particles. The shape of the carrier obtained at that time was almost spherical. In addition, X-ray diffraction and fluorescence X
As a result of the line analysis, the ratio of the spinel phase (Cu-Zn-ferrite) and the magnet plumbundite phase (Sr ferrite) was 2: 1 which was almost the same as the charged amount. The bulk density was 2.32 g / cm ³ . When the resistance of the carrier particles was measured, it was 6.2 × 10 ⁹ Ω · cm. After magnetically measuring this carrier after saturating it with a magnetic field of 10 kilo Oersted, the magnetic characteristics at that time were σ ₁₀₀₀ = 142 emu / cm ³ , σ _r = 104 em.
u / cm ³ , σ ₃₀₀ = 122 emu / cm ³ ,

[0165]

[Outside 13] Met. Then, | σ ₁₀₀₀ −σ ₃₀₀ | / σ ₁₀₀₀ =
It was 0.14.

Further, the surface of this carrier was coated with a styrene-2-ethylhexyl methacrylate (45/55) copolymer by a fluidized bed coating method to obtain a carrier A. The specific resistance of carrier A at that time is 9.5.
It was × 10 ¹² Ω · cm.

[Carrier Production Example B] The molar ratio of Fe ₂ O
₃ = 50 mol%, CuO = 20 mol%, ZnO = 30 mol%, while Fe ₂ O ₃ = 85 mol%, BaO = 12 mol%, ZnO = 3 mol% Weighed and mixed using a ball mill.

After calcination of each of them, the mixture was pulverized with a ball mill, the above-mentioned formulations were mixed at a ratio of 1.5: 1, polyvinyl alcohol, a defoaming agent and a dispersant were added to make a slurry, and a spray dryer was used. It was used for granulation, drying, and sintering. Further classification was performed to obtain carrier particles having an average particle size of 45 μm. The shape of the carrier obtained at that time was almost spherical. As a result of X-ray diffraction measurement and fluorescent X-ray measurement, the molar ratio between the spinel phase and the magnetplumbite phase (Ba ferrite) was almost the same as the charged amount (1.6: 1). Bulk density is 2.30
It was g / cm ³ . When the resistance of the carrier particles was measured, it was 9.2 × 10 ⁹ Ω · cm. After saturating this carrier with a magnetic field of 10 kilo Oersted, magnetic measurement was carried out. As a result, the magnetic characteristic was σ ₁₀₀₀ = 67.
_{^{emu / cm 3, σ r =}} 36emu / cm 3, σ 300 =
52 emu / cm ³ ,

[0169]

[Outside 14] Met. Then, | σ ₁₀₀₀ −σ ₃₀₀ | / σ ₁₀₀₀ =
It was 0.22.

Further, the surface of this carrier was coated with a styrene-2-ethylhexyl methacrylate (45/55) copolymer by a fluidized bed coating method to obtain a carrier B. The specific resistance of carrier B at that time is 1.3.
It was × 10 ¹² Ω · cm.

[Carrier Production Example C] The molar ratio of Fe ₂ O
₃ = 62 mol%, ZnO = 16 mol%, CuO = 22 mol% were weighed and mixed using a ball mill. The mixed powder was calcined and then pulverized. The crushed sample was made into a slurry, and the slurry was granulated with a spray dryer to sinter the granulated powder. The obtained sintered powder was classified by an air classifier to obtain carrier particles having an average particle size of 50 μm. The shape of the carrier obtained at that time was almost spherical. The bulk density was 2.77 g / cm ³ . When the resistance of the carrier particles was measured, it was 4.0 ×
It was 10 ⁹ Ω · cm. As a result of magnetic measurement of this carrier in a magnetic field of 10 kilo Oersted, the magnetic characteristic at that time is σ ₁₀₀₀ = 214 emu / cm ³ , σ _r
= 2 emu / cm ³ , σ ₃₀₀ = 113 emu / cm ³ ,

[0172]

[Outside 15] Met. At that time, | σ ₁₀₀₀ −σ ₃₀₀ | σ ₁₀₀₀ = 0.
It was 47.

The surface of the obtained carrier was coated in the same manner as in Carrier Production Example A to obtain Carrier C. The specific resistance of the carrier C at this time was 3.2 × 10 ¹² Ω · cm.

[Carrier Production Example D] The molar ratio of Fe ₂ O
₃ = 60 mol%, SrCO ₃ = 3 mol%, ZnO = 21
Mol% and CuO = 16 mol% were weighed and mixed using a ball mill. This is Carrier Production Example C
Similarly to the above, carrier particles having an average particle diameter of 52 m were obtained. The shape of the carrier obtained at that time was almost spherical. As a result of the X-ray diffraction measurement and the fluorescent X-ray measurement, the molar ratio of the spinel phase (Cu-Zn ferrite) and the magnet prambitite phase (Sr ferrite) was about 15: 1. The bulk density was 2.32 g / cm ³ . When the resistance of the carrier particles was measured, it was 1 × 10 ⁹ Ω · cm. As a result of magnetic measurement of this carrier, the magnetic characteristics at that time are σ ₁₀₀₀ = 58 emu / cm ³ , σ _r =
6 emu / cm ³ , σ ₃₀₀ = 20 emu / cm ³ ,

[0175]

[Outside 16] Met. Then, | σ ₁₀₀₀ −σ ₃₀₀ | / σ ₁₀₀₀ =
It was 0.66.

The surface of the obtained carrier was coated in the same manner as in Carrier Production Example A to obtain Carrier D. The specific resistance of the carrier D at this time was 1.5 × 10 ¹² Ω · cm.

Table 2 shows the physical properties of the above carriers A to D.

[0178]

[Table 2]

[Titanium Oxide Treatment Example A] Hydrophilic titanium oxide fine particles (particle size: 0.05 μm) were added to an aqueous system and mixed and stirred by a mechanical method. To this system, titanium oxide 1
Vinyltriethoxysilane, which is a coupling agent with a treatment amount of 30% by weight with respect to 00 parts by weight, is added and dispersed,
Surface treatment was performed while hydrolyzing.

At this time, titanium oxide was not united.
After that, it was dried and crushed to obtain titanium oxide A having an average particle size of 0.05 μm, a hydrophobicity of 60%, and a light transmittance of 81% at 400 nm.

[Titanium Oxide Treatment Example B] Hydrophilic titanium oxide fine particles (particle diameter 0.04 μm) were added to an aqueous system, and mixed and stirred by a mechanical method. To this system, titanium oxide 1
Vinyltriethoxysilane, which is a coupling agent having a treatment amount of 41% by weight with respect to 00 parts by weight, is added and dispersed,
Surface treatment was performed while hydrolyzing.

At this time, titanium oxide was not united.
After that, it was dried and crushed to obtain titanium oxide B having an average particle size of 0.08 μm, a hydrophobicity of 55%, and a light transmittance of 35% at 400 nm.

[Titanium Oxide Treatment Example C] Hydrophilic titanium oxide fine particles (particle diameter 0.04 μm) were added to an aqueous system, and mixed and stirred by a mechanical method. To this system, titanium oxide 1
Vinyltriethoxysilane as a coupling agent having a treatment amount of 60% by weight with respect to 00 parts by weight is added and dispersed,
Surface treatment was performed while hydrolyzing. At this time, the titanium oxide particles were not united. After this, dry and crush,
Titanium oxide C having an average particle size of 0.30 μm, a hydrophobicity of 99% and a light transmittance of 8% at 400 nm was obtained.

Table 3 shows the physical properties of the above titanium oxides A to C.

[0185]

[Table 3]

[Photoreceptor Production Example A] 10 parts by weight of conductive titanium oxide (tin oxide coat, average primary particle size 0.4 μ), 10 parts by weight of phenol resin precursor (resole type), 10 parts by weight of methanol, and 10 parts by weight of butanol. After the parts were dispersed by a sand mill, the aluminum cylinder having an outer diameter of 80 mm and a length of 360 mm was applied by dipping and cured at 140 ° C., and then a conductive layer having a volume resistance of 5 × 10 ⁹ Ωcm and a thickness of 20 μ was provided.

Next, 10 parts by weight of methoxymethylated nylon (degree of methoxymethylation of about 30%) described below is used.

[0188]

[Outside 17] And 150 parts by weight of isopropanol were mixed and dissolved, and then dip-coated on the conductive layer to form a 1 μ undercoat layer.

Next, 10 parts by weight of the following azo pigment,

[0190]

[Outside 18] Polycarbonate resin below (bisphenol A molecular weight 3
0000) 5 parts by weight,

[0191]

[Outside 19] And 700 parts by weight of cyclohexanone are dispersed in a sand mill, and the dispersion is dip-coated on the undercoat layer.
A charge generation layer having a thickness of 0.05 μm was obtained.

Next, 10 parts by weight of the following triphenylamine,

[0193]

[Outside 20] Polycarbonate resin with the following structure (bisphenol Z
Mold, molecular weight 20000) 10 parts by weight

[0194]

[Outside 21] 50 parts by weight of monochlorobenzene and 1 part of dichloromethane
After stirring and mixing 5 parts by weight, the charge generation layer was dip-coated on the charge generation layer. The coated cylinder was dried with hot air to give a 20 μ charge transport layer.

Next, 1 part by weight of carbon fluoride fine powder (average particle size: 0.23 μ, manufactured by Central Glass Co., Ltd.), and the following polycarbonate resin (bisphenol Z, molecular weight 800)
00) 6 parts by weight,

[0196]

[Outside 22] The following perfluoroalkyl acrylate-methyl methacrylate block copolymer (molecular weight 30000) 0.1
Parts by weight

[0197]

[Outside 23] 120 parts by weight of monochlorobenzene and 80 parts by weight of dichloromethane were dispersed and mixed in a sand mill. And 3 parts by weight of the following triphenylamine

[0198]

[Outside 24] Was mixed and dissolved, and the charge-transporting layer was applied by spray coating to form a protective layer having a thickness of 5 μm to obtain a photoconductor A.

[Measurement of F / C Ratio XPS] After the surface of the photoconductor A was peeled off, surface elements were quantified by an ESCALAB200-X type X-ray photoelectron spectrometer manufactured by VG. X
Using MgCa (300 W) as a radiation source, measurement was performed at a depth of several Å in a region of 2 × 3 mm. The surface of the photoconductor A of Production Example A had F atoms of 5% and 2% and C atoms of 81.3%, and the F / C ratio was 0.064.

[Photosensitive Member Production Example B] 10 parts by weight of conductive titanium oxide (tin oxide coating, average primary particle size 0.4 μ), 10 parts by weight of phenol resin precursor (resole type), 10 parts by weight of methanol, and 10 parts of butanol. After dispersing parts by weight in a sand mill, the aluminum cylinder having an outer diameter of 80 mm and a length of 360 mm was applied by dipping and cured at 140 ° C., and then a conductive layer having a volume resistance of 5 × 10 ⁹ cm and a thickness of 20 μ was provided.

Next, 10 parts by weight of methoxymethylated nylon (degree of methoxymethylation of about 30%) described below is used.

[0202]

[Outside 25] And 150 parts by weight of isopropanol were mixed and dissolved, and then dip-coated on the conductive layer to form a 1 μ undercoat layer.

Next, 10 parts by weight of the following azo pigment,

[0204]

[Outside 26] Polycarbonate resin below (bisphenol A molecular weight 3
0000) 5 parts by weight,

[0205]

[Outside 27] And 700 parts by weight of cyclohexanone are dispersed in a sand mill, and the dispersion is dip-coated on the undercoat layer.
A charge generation layer having a thickness of 0.05 μm was obtained.

Next, 10 parts by weight of the following triphenylamine,

[0207]

[Outside 28] Polycarbonate resin with the following structure (bisphenol Z
Mold, molecular weight 20000) 10 parts by weight

[0208]

[Outside 29] 50 parts by weight of monochlorobenzene and 1 part of dichloromethane
After stirring and mixing 5 parts by weight, the charge generation layer was dip-coated on the charge generation layer. The coated cylinder was dried with hot air to give a 20 μ charge transport layer.

Next, 1 part by weight of spherical three-dimensional crosslinked polysiloxane fine particles (average particle size 0.29 μ, manufactured by Toshiba Silicone Co.) and the following polycarbonate resin (bisphenol Z,
Molecular weight 80,000) 6 parts by weight,

[0210]

[Outside 30] The following polydimethylsiloxane methacrylate-methyl methacrylate block copolymer (molecular weight 50,000, S
i amount 12 wt%) 0.1 parts by weight

[0211]

[Outside 31] 120 parts by weight of monochlorobenzene and 80 parts by weight of dichloromethane were dispersed and mixed in a sand mill. And 3 parts by weight of the following triphenylamine

[0212]

[Outside 32] Was mixed and dissolved, and the charge-transporting layer was applied by spray coating to form a 3 μm protective layer to prepare a photoconductor B.

[Si / C Ratio XPS Measurement] After peeling off the surface of the photoconductor B, ESCALAB200-X manufactured by VG.
Quantitative analysis of surface elements was carried out using an X-ray photoelectron spectrometer.
2 x 3mm using MgCa (300W) as X-ray source
Was measured at a depth of several Å. The surface of the photoconductor B of Production Example B has 10.2% Si atoms and 69.3% C atoms.
And the Si / C ratio was 0.147.

[Photoreceptor Production Example C] A photoconductor C is the photoconductor A of Photoreceptor Production Example A on which a charge transport layer having no protective layer is applied.

The F / C ratio and F / O ratio of the surface layers of the photoconductors A and C are shown in Table 4, and the Si of the surface layer of the photoconductor B is
Table 5 shows the / C ratio and the Si / O ratio.

[0216]

[Table 4]

[0217]

[Table 5]

[Preparation of Toner] 0.2 parts by weight of titanium oxide was externally added and mixed with 100 parts by weight of toner particles to prepare a toner.

[Preparation of Developer and Evaluation Method] The carrier was saturated and magnetized in a magnetic field of 10 kilo Oersted, and then the carrier and toner were mixed so as to have a toner concentration of 5% by weight to obtain a developer. A full color laser copying machine CLC-500 manufactured by Canon was remodeled, and an image was printed using the drum of the present invention. FIG. 4 shows a schematic diagram of the developing area portion of the developing device and the photosensitive drum at this time. The distance between the developing sleeve and the developer regulating member is 400 μm, the peripheral speed ratio between the developing sleeve and the photosensitive drum is 1.3: 1, and
The developing conditions were a magnetic field strength of the developing electrode of 1000 oersted, an alternating electric field of 2000 V _pp and a frequency of 3000 Hz, and the distance between the sleeve and the photosensitive drum was 500 μm.
At this time, the spikes of the developing brush near the developing pole on the developing sleeve were observed with a microscope to evaluate the image formation. Furthermore, the developing device is spun at a speed of 200 rpm for 30 minutes,
Image evaluation was performed. In addition, the idle rotation test is a normal temperature and normal humidity environment (23 ° C., 60% RH), low temperature and low humidity environment (15 ° C., 10% RH).
The image quality was evaluated in two environments (RH).

Next, a method of evaluating fixability in the examples of the present invention will be described.

As a recording material, commercially available copying machine paper Canon New Dry Paper (Canon Sales Company 54 g / m 2
² paper) to obtain an unfixed image and a commercial copying machine Cano
The fixing device of nFC-1 (manufactured by Canon Inc.) was modified, and the fixing temperature was modulated every 5 ° C. (120 to 200 ° C.) and the fixing start temperature and the offset temperature were observed.

Here, the fixing start temperature was determined by rubbing the obtained fixed image with sillbon paper 10 times in a reciprocating manner under a load of about 100 g, and peeling of the image was reduced by 10 at a reduction rate (%) of reflection density.
The temperature was set to be not more than%.

[Examples 1 to 5 and Comparative Examples 1 to 5] Toners A to D, titanium oxides A to C, and carrier A described above.
To D and photoconductors A to C were used in the combinations shown in Table 6, toners and developers were prepared, and images were evaluated according to the above evaluation methods.

Table 6 shows the evaluation results.

[0225]

[Table 6]

[0226]

INDUSTRIAL APPLICABILITY The present invention provides a developer for developing an electrostatic image containing a toner and a carrier, wherein the toner contains toner particles and titanium oxide, and the toner particles are directly produced by a suspension polymerization method. Which is a toner particle having at least a colorant and a resin component, and the resin component constituting the toner particle has a molecular weight distribution by GPC,
At least one of the molecular weight peaks has a molecular weight in the range of 5,000 to 50,000 and contains at least one polar component, and the titanium oxide has a content of 0.01
Has an average particle size of from 0.2 to 0.2 μm and a hydrophobicity of from 20 to 98%, the carrier has an average particle size of from 5 to 100 μm and a bulk density of 3.0 g / cm ³ or less. The magnetic properties of the carrier are (i) the magnetization strength (σ) at 1000 Oersted after magnetic saturation.
₁₀₀₀ ) is 30 to 150 emu / cm ³ , and (i
i) The strength of magnetization (remanent magnetization: σ _r ) in a magnetic field of 0 Oersted is 25 emu / cm ³ or more, and (ii)
i) the coercive force is less than 300 Oersted, and (i
v) The following formula

[0227]

[Outside 33] (In the formula, σ ₁₀₀₀ and σ ₃₀₀ represent the strength of magnetization (emu / cm ³ ) at 1000 oersted and 300 oersted after being magnetically saturated, respectively). It is not easily affected by fluctuations, has stable triboelectrification in each environment, and has high resolution, high highlight reproducibility, and high fine line reproducibility. Further, it is possible to obtain excellent fixability.

Further, a latent image is formed by using an electrophotographic photoreceptor having a photosensitive layer having at least a conductive support and a charge generating layer and a charge transporting layer, and the latent image is formed. In an image forming method of visualizing with a developer and transferring to a transfer material, the surface layer of the electrophotographic photoreceptor contains a substance having a fluorine atom and / or a silicon atom, and the fluorine atom measured by XPS is used. The ratio of the silicon atom and the carbon atom is as follows: Fluorine atom / carbon atom (F / C) = 0.01 to 1.00 Silicon atom / carbon atom (Si / C) = 0.03 to 1.00 Since the above-mentioned developer is used in a satisfactory image forming method, even if the toner has a relatively strong adhesive force because the resin component forming the toner particles has a polar component. , The surface layer of the photoconductor is Due to the presence of a certain amount of silicon atoms, the surface of the photoconductor has low surface energy, so that good transferability can be obtained, and the cleaning property is excellent. It can be obtained satisfactorily.

[Brief description of drawings]

FIG. 1 is a schematic diagram schematically showing a magnetic characteristic curve (hysteresis curve). The horizontal axis represents the external magnetic field (Oersted), and the vertical axis represents the strength of magnetization of the carrier per unit volume.

FIG. 2 is a schematic diagram schematically showing a magnetic characteristic curve (hysteresis curve). The numbers shown in the box are (σ
The value is ( ₁₀₀₀ − σ ₃₀₀ ) / σ ₁₀₀₀ .

FIG. 3 is a schematic view schematically showing an electric resistance measuring device.

[Explanation of symbols]

 A cell d Thickness 1 Lower electrode 2 Upper electrode 3 Insulator 4 Ammeter 5 Voltmeter 6 Constant voltage device 7 Carrier 8 Guide ring

Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location G03G 9/08 9/107 13/08 13/09 G03G 9/08 374 384 9/10 321 13/08 (72 ) Inventor Kasuya Valuable Canon Inc., 3-30-2 Shimomaruko, Ota-ku, Tokyo

Claims (17)

[Claims] 1. A developer for electrostatic charge image development comprising a toner and a carrier, wherein the toner comprises toner particles and titanium oxide,
The toner particles were obtained directly by suspension polymerization method,
Toner particles having at least a colorant and a resin component, the resin component constituting the toner particles, in the molecular weight distribution by GPC, at least one of the molecular weight peak is in the range of 5,000 to 50,000 molecular weight,
And at least one polar component, the titanium oxide has an average particle size of 0.01 to 0.2 μm and a hydrophobicity of 20 to 98%, and the carrier is 5 To 100 μm average particle size and 3.0
The carrier has a bulk density of g / cm ³ or less, and the magnetic properties of the carrier are (i) the magnetization strength ( ₁₀₀₀ ) at 1000 Oersted after magnetic saturation is 30 to 1
50 emu / cm ³ and (ii) the strength of magnetization (remanent magnetization: σ _r ) in a magnetic field of 0 Oersted is 25 emu.
/ Cm ³ or more, (iii) the coercive force is less than 300 Oersted, and (iv) the following formula: (In the formula, σ ₁₀₀₀ and σ ₃₀₀ respectively indicate the strength of magnetization (emu / cm ³ ) at 1000 oersted and 300 oersted after being magnetically saturated.) Developer for charge image development. 2. The developer for developing an electrostatic charge image according to claim 1, wherein the carrier is substantially spherical and has a sphericity of 2 or less. 3. The carrier is a group IA or IIA of the periodic table.
Group, Group IIIA, Group IVA, Group VA, Group VIA, IB
Group, IIB Group, IVB Group, VB Group, VIB Group, VIIB
A ferrite particle containing at least one element selected from the group consisting of Group VIII and Group VIII, and having a content of other elements of less than 1% by weight. The developer for developing an electrostatic image as described above. 4. The carrier is a spinel-structure single phase, a magnet-plumbite structure single-phase, a composite phase having at least a spinel structure or a magnet-plumbite structure, a composite phase of a spinel structure and a magnet-plumbite structure, and at that time, The developer for developing an electrostatic charge image according to claim 1, wherein a molar ratio of the spinel phase and the magnetplumbite phase is 1: 1 to 10: 1. 5. The carrier is 10 ^{8 to} 10 ¹³ Ω · c
The developer for developing an electrostatic charge image according to claim 1, having a specific resistance of m. 6. The developer for developing an electrostatic charge image according to claim 1, wherein the titanium oxide is surface-treated by hydrolysis of a coupling agent. 7. The developer for developing an electrostatic charge image according to claim 1, wherein the titanium oxide has a light transmittance of 40% or more at a light length of 400 nm. 8. A latent image is formed using an electrophotographic photoreceptor having at least a conductive support and a photosensitive layer having a laminated structure of a charge generation layer and a charge transport layer, and the latent image is formed. In a method for forming an image by using a developer to transfer the image onto a transfer material, a substance having a fluorine atom and / or a silicon atom is present in the surface layer of the electrophotographic photosensitive member, and an XPS measurement is conducted. The ratio of the fluorine atom and the silicon atom to the carbon atom is as follows: Fluorine atom / carbon atom (F / C) = 0.01 to 1.00 Silicon atom / carbon atom (Si / C) = 0.03 to 1 0.000, the developer contains toner particles and toner containing titanium oxide, and the toner particles contain at least a colorant and a resin component directly obtained by a suspension polymerization method. Toner particles having Resin component constituting the toner particles, the molecular weight distribution by GPC, at least one molecular weight peak molecular weight of 5,000 to 5
The titanium oxide has an average particle size of 0.01 to 0.2 μm and a hydrophobicity of 20 to 98%. And the carrier has an average particle size of 5 to 100 μm and 3.0
The carrier has a bulk density of g / cm ³ or less, and the magnetic properties of the carrier are (i) the magnetization strength ( ₁₀₀₀ ) at 1000 Oersted after magnetic saturation is 30 to 1
50 emu / cm ³ and (ii) the strength of magnetization (remanent magnetization: σ _r ) in a magnetic field of 0 Oersted is 25 emu.
/ Cm ³ or more, (iii) the coercive force is less than 300 Oersted, and (iv) the following formula: (In the formula, σ ₁₀₀₀ and σ ₃₀₀ respectively indicate the strength of magnetization (emu / cm ³ ) at 1000 oersted and 300 oersted after being magnetically saturated.) Forming method. 9. The image forming method according to claim 8, wherein the surface layer of the electrophotographic photoreceptor contains polycarbonate. 10. The image forming method according to claim 8, wherein the surface layer of the electrophotographic photosensitive member contains a polycarbonate synthesized by using an asymmetric diol. 11. The image forming method according to claim 8, wherein the electrophotographic photosensitive member has a protective layer on the photosensitive layer, and the protective layer contains polycarbonate. 12. The image forming method according to claim 8, wherein the carrier is substantially spherical and has a sphericity of 2 or less. 13. The carrier is a group IA or II of the periodic table.
Group A, Group IIIA, Group IVA, Group VA, Group VIA, IB
Group, IIB Group, IVB Group, VB Group, VIB Group, VIIB
9. Ferrite particles containing at least one element selected from the group consisting of Group VIII and Group VIII, and having a content of other elements of less than 1% by weight. Image forming method. 14. The carrier is a spinel structure single phase, a magnet plumbite structure single phase, a composite phase having at least a spinel structure or a magnet plumbite structure,
9. The image forming method according to claim 8, wherein the composite phase has a spinel structure and a magnet-plumbite structure, and the molar ratio of the spinel phase to the magnet-plumbite phase is 1: 1 to 10: 1. . 15. The carrier is 10 ^{8 to} 10 ¹³ Ω.multidot.
The image forming method according to claim 8, having a specific resistance of cm. 16. The image forming method according to claim 8, wherein the titanium oxide is surface-treated by hydrolysis of a coupling agent. 17. The image forming method according to claim 8, wherein the titanium oxide has a light transmittance of 40% or more at a light length of 400 nm.