JP3262505B2 - Electrostatic image developing toner, apparatus unit and image forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic image for developing an electrostatic image in an image forming method such as electrophotography, electrostatic recording, and electrostatic printing, an apparatus unit having the toner, and the toner. And an image forming method using the same.

[0002]

2. Description of the Related Art An electrophotographic method is disclosed in U.S. Pat.
Numerous methods are known as described in Japanese Patent Publication No. 7,691, Japanese Patent Publication No. 42-23910, and Japanese Patent Publication No. 43-24748. Generally, the surface of an electrostatic image carrier using a photoconductive material is uniformly charged by various means, and then an electrostatic image is formed on the electrostatic image carrier, and then the electrostatic image is transferred to a toner. The toner image is transferred to a transfer material such as paper as necessary, and then fixed by heating, pressure, heat and pressure, or solvent vapor to obtain a copy or print. Further, the toner remaining on the electrostatic latent image carrier without being transferred is cleaned by various methods, and the above-described steps are repeated.

[0003] Of these methods, a method for removing residual toner on the electrostatic image carrier is performed by bringing a cleaning member into contact with the electrostatic image carrier, such as a blade cleaning system, a fur brush cleaning system, and a magnetic brush cleaning system. It is common. In this case, since the cleaning member is pressed against the electrostatic image carrier with an appropriate pressure, a phenomenon occurs in which the electrostatic image carrier is damaged or the toner is fixed during repeated use.

On the other hand, many contact charging methods have recently been proposed as charging methods, in which a charging member is brought into contact with the surface of an electrostatic image carrier to apply a voltage obtained by superimposing a DC voltage and an AC voltage to perform charging. Lower applied voltages can be used compared to conventional corona charging methods. In addition, there is an advantage that generation of ozone is small. According to this contact charging method, for example, as shown in FIG. 3, a charging roller 2 serving as a charging member is contact-driven and rotated on an electrostatic image carrier (photosensitive drum) 1, and an AC voltage _Vac and a DC voltage _{Vdc are applied. Is} applied to the charging roller 2 by superimposing the voltage (V _ac + V _cd )
The photosensitive drum 1 can be uniformly charged.

As can be understood from the above description, the charging roller 2 needs to maintain conductivity, and the charging roller 2 conventionally has an E around the metal core.
A material in which a conductive elastic member in which carbon is dispersed in an elastic rubber such as PDM and NBR is formed is used. Therefore, the charging roller 2 has a rubber hardness of ASKER.
At -C, it had to be 70 ° or more. When contact charging is performed using the charging roller 2 as described above, the conductive member 2b vibrates due to the AC component _Vac of the voltage applied to the cored bar 2a, and the charging roller 2 and the photosensitive drum A sound is generated at the nip portion (contact portion) with No. 1 and causes a problem. The generation of this noise tended to increase with increasing hardness.

If the AC component _Vac of the applied voltage is eliminated, no sound is generated, but uniform charging of the surface of the photosensitive drum 1 cannot be obtained, and spot-like charging unevenness is likely to occur.

[0007] The applicant of the present invention disclosed in Japanese Patent Application Laid-Open No. 1-119161 that the hardness of a charging member was set to 6 by ASKER-C.
A charging method for reducing the noise level due to charging by setting the angle to 0 ° or less has been proposed.

Recently, a copying machine using electrophotography or
Technical requirements for low energy or high speed printers are increasing. As a result, the toner is preferably designed to soften with low energy. When such a toner is combined with the above-described charging member having a reduced hardness, the toner tends to adhere to the surface of the electrostatic image carrier, and the problem of shortening the life of the electrostatic image carrier tends to occur. The tendency is particularly strong when the charging member is in the form of a roller. This is because, when the hardness of the charging member is reduced, the charging member is deformed when the driving force of the electrostatic image carrier is transmitted to the charging member via the contact surface. It is presumed that the force is dispersed and the slippage occurs on the surfaces of the charging member and the electrostatic image carrier.

In order to avoid the phenomenon that toner adheres to the electrostatic image carrier, for example, Japanese Patent Application Laid-Open No.
In Japanese Patent Application Publication No. 2002-115, it is proposed to add both a friction reducing developing material and a polishing material to a toner. However, in this method, it is difficult to remove low electric resistance substances such as paper dust and ozone adducts which are generated or adhered to the surface of the electrostatic image carrier by repeated use. There has been a problem that an image deletion phenomenon occurs in which an electrostatic charge image on the electrostatic charge image carrier is disturbed.

In order to solve these problems, Japanese Patent Application Laid-Open No. Sho 62-6107
No. 3, JP-A-3-10311 proposes a toner containing a metal oxide and silica fine powder. However, in this method, the load of the toner in the charging step and the cleaning step has been increased due to the recent demand for higher speed of the recording apparatus, so that the fusion of the toner to the electrostatic image carrier and the surface of the electrostatic image carrier have been performed. It has become difficult to prevent non-uniform shaving.

Further, Japanese Patent Application Laid-Open No. 4-44051 proposes a toner containing hydrophobic silica particles, resin fine particles and metal oxide. In this method, since the environmental characteristics of each particle are not specified, the toner is easily affected by the surroundings, and there is a problem that the charge amount is reduced in a high-temperature and high-humidity environment and the charge is easily increased in a low-temperature and low-humidity environment. Further, it is necessary to further suppress generation of scratches on the electrostatic image carrier and fixation of the toner.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner for developing an electrostatic image, an apparatus unit and an image forming method which solve the above-mentioned problems.

An object of the present invention is to prevent toner from being fixed to an electrostatic image carrier and uneven scraping of the electrostatic image carrier, and to obtain a high-quality image for a long period of time even when applied to a high-speed apparatus. To provide a toner for developing an electrostatic image.

An object of the present invention is to provide an apparatus unit having the above toner.

A further object of the present invention is to apply a voltage having an alternating current component to the charging member, to use a contact charging method that generates less ozone, to eliminate noise due to charging, to achieve low-temperature fixing, and to achieve higher speed. An object of the present invention is to provide an image forming method that can achieve a long life without causing toner to adhere and uneven shaving on the surface of the electrostatic image holding member even when the toner is used.

[0016]

Means for Solving the Problems The present invention provides at least:
2. An electrostatic image developing toner having toner particles, inorganic fine powder, resin fine particles and metal oxide particles, wherein the toner for electrostatic image development has a weight average particle diameter of 4 to 12 μm.
The number% of 17 μm or less is 30% or less, the primary particles of the inorganic fine powder have an average particle diameter of 1 to 50 nm, and the fine resin particles have an average particle diameter of 0.1 to 2 μm. A metal oxide having a coefficient SF of 100 or more and less than 150, an average particle diameter of 0.3 to 3 μm, and a shape factor SF1 of 150 to 250; .

Further, according to the present invention, there is provided an apparatus unit detachably mountable to an image forming apparatus main body, wherein an electrostatic image holder is used and an electrostatic image formed on the electrostatic image holder is formed by using an electrostatic image developing toner. And a developing unit for developing the electrostatic image. The electrostatic image developing toner contains at least toner particles, inorganic fine powder, resin fine particles and metal oxide particles, and the weight average of the electrostatic image developing toner. The particle size is 4 to 12 μm, the number% of 3.17 μm or less is 30 number% or less, and the primary particles of the inorganic fine powder have an average particle size of 1 to 50 nm.
The resin fine particles have an average particle diameter of 0.1 to 2 μm, a shape factor SF1 of 100 or more and less than 150, and the metal oxide has an average particle diameter of 0.3 to 3 μm, The present invention relates to an apparatus unit, wherein the shape factor SF1 is 150 to 250.

Further, the present invention provides a step of charging the surface of the electrostatic image holder, a step of forming an electrostatic image on the electrostatic image holder, and developing the electrostatic image with a toner for developing an electrostatic image. Forming, a step of transferring the toner image formed on the electrostatic image holding member to a transfer material, and a step of cleaning the surface of the electrostatic image holding member by contacting a cleaning unit after the transfer, In the image forming method of repeating the above process using the electrostatic image holder after cleaning, the electrostatic image developing toner contains at least toner particles, inorganic fine powder, resin fine particles and metal oxide particles, The toner for developing an electrostatic image has a weight average particle diameter of 4 to 12.
μm, and the number% of 3.17 μm or less is 30 number% or less, and the primary particles of the inorganic fine powder have an average particle diameter of 1 to 5
0 nm, and the resin fine particles have an average particle size of 0.1 to 2
μm, and the shape factor SF1 is 100 or more and less than 150, and the metal oxide has an average particle size of 0.3 to 3 μm.
Wherein the shape factor SF1 is 150 to 250.

Further, according to the present invention, there is provided a step of applying a voltage having at least an AC component to a charging member, and bringing the charging member into contact with the electrostatic image holder to charge the surface of the electrostatic image holder. Forming an electrostatic image, and developing the electrostatic image with toner, wherein the charging member includes an upper layer portion made of a high-resistance element that contacts the electrostatic image holding member; A conductive lower layer part to which a voltage having at least an AC component is applied, which constitutes a lower layer of the upper layer part, wherein the electrostatic image holding member has at least a conductive support and a charge generation layer. Having a fluorine atom, a silicon atom or both in the surface layer of the electrostatic image holder, the toner has at least toner particles, inorganic fine powder, resin fine particles and metal oxide particles, The toner has a weight average particle size of 4 to 12 μm The number% of 3.17 μm or less is 30 number% or less, the primary particles of the inorganic fine powder have an average particle size of 1 to 50 nm, and the resin fine particles have an average particle size of 0.1 to 2 μm. And its shape factor SF1 is 100
The metal oxide has an average particle diameter of 0.3 to 3 μm and a shape factor SF1 of 150 to less than 150.
To 250, which is an image forming method.

The present invention, by adopting the above-described structure, can sufficiently exhibit effects even in the recent demand for higher speed and higher durability.

This will be described more specifically. The released inorganic fine powder and metal oxide mainly scrape off paper powder, toner and the like adhering to the surface of the electrostatic image carrier. Among these, the inorganic fine powder having a small particle diameter and a large specific surface area having the above-described structure finely shaves the electrostatic image carrier and reduces the frictional resistance between the surface of the electrostatic image carrier and the cleaning member and the charging member. It is also effective.

On the other hand, the metal oxide having the above-described particle diameter and shape is effective for removing the adhered substances which cannot be removed even by inorganic fine powder and which are firmly fixed or fixed over a wide range.

Further, by including resin fine particles having the above-mentioned particle diameter and shape, when there is a portion where the metal oxide is present in a non-uniform manner, it is possible to relieve the portion of the metal oxide from being extremely scraped compared to the surroundings. In addition, it is easy to clean by adsorbing excess inorganic fine powder that has been released. In addition, a small amount of these resin fine particles slip through the cleaner,
It collects toner and the like that have passed through a very small amount of cleaning, and prevents contamination of a charging member, which leads to poor charging, damage to the electrostatic image carrier, and prevention of sticking.

By defining the particle size distribution of the toner and the particle size and shape of each external additive to a high degree, the above-mentioned effects can be effectively exerted. Also, the charging characteristics of the toner are stabilized.

Further, by making the chargeability of the inorganic fine powder and the resin fine particles the same as that of the toner, the chargeability of the toner can be stabilized.

In the transfer step, when the toner on the electrostatic image carrier is transferred onto the transfer material, the metal oxide charged to the opposite polarity to the toner is transferred from the toner on the transfer material to the surface of the electrostatic image carrier or It moves to the toner on the electrostatic image carrier. Alternatively, due to variations during external addition, a larger amount of the toner to which the metal oxide has adhered remains on the surface of the electrostatic image carrier during transfer. For any of the reasons, a large proportion of metal oxide remains on the electrostatic image carrier after the transfer step, and the deposits on the surface of the electrostatic image carrier can be effectively removed.

Further, in the charging step, in the case where a soft charging member having a hardness of 60 ° or less according to ASKER-C is used, the contaminant is removed from the surface of the charging member. However, the charging member surface is preferably deformed flexibly at the contact portion with the electrostatic image carrier and sufficiently grounded to the electrostatic image carrier, so that poor charging is less likely to occur.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The electrostatic image developing toner of the present invention has a weight average particle diameter of 4 to 12 μm and 3.17 μm.
The following number% is 30 number% or less.

When the weight average particle diameter of the toner is less than 4 μm, the fluidity is reduced and the adhesive force is increased.
Cleaning performance decreases. On the other hand, if it exceeds 12 μm, a problem occurs in image reproducibility. If the number% of 3.17 μm or less exceeds 30 number%, a problem of cleaning fog occurs.

The measurement of the weight average particle diameter of the toner of the present invention is as follows.
A Coulter Counter TA-II type or Coulter Multisizer (manufactured by Coulter Inc.) is used. As the electrolytic solution, a 1% NaCl aqueous solution is prepared using primary sodium chloride. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) can be used. As a measuring method, 0.1 to 5 ml of a surfactant (preferably an alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of the electric field aqueous solution, and 2 to 20 mg of a measurement sample is further added. The electrolyte in which the sample is suspended is subjected to dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser, and the volume and the number of toner particles having a size of 2 μm or more are measured by using the measuring device, using a 100 μm aperture as an aperture. Calculate the number distribution.

The present invention is more effective when the particle size of the external additive is determined with respect to the toner particle size. The primary particles of the inorganic fine powder have an average particle size of 1 to 50 nm, the fine resin particles have an average particle size of 0.1 to 2 μm, and the metal oxide has an average particle size of 0.3 to 3 μm.

The average particle size of the primary particles of the inorganic fine powder is 1 nm
If it is less than 1, the fluidity of the toner is improved, but the environmental characteristics tend to be deteriorated. On the other hand, if it exceeds 50 nm, the fluidity of the toner is not sufficiently added, and fog and developing property are likely to be deteriorated.

When the average particle diameter of the resin fine particles is less than 0.1 μm, the abrasion of the electrostatic image carrier by the metal oxide cannot be sufficiently reduced. Further, many of the cleaning members slip through, and the charging member is easily contaminated. On the other hand, if it exceeds 2 μm, the released inorganic fine powder cannot be adsorbed and collected.

When the average particle diameter of the metal oxide is less than 0.3 μm, it is difficult to remove the adhered matter on the electrostatic image carrier, or the metal oxide easily slips through the cleaning member to cause image defects. On the other hand, when the thickness exceeds 3 μm, the surface of the electrostatic charge image carrier and the developer carrier (developing sleeve) are significantly scraped.

Further, one of the features of the present invention is that the resin fine particles and the metal oxide each have a shape factor in the range described below.

The resin fine particles have a shape factor SF1 of 100 or more and less than 150 (more preferably, SF1 of 115 or more and less than 145), and a shape factor SF2 of 110 or more and 2 or less.
Less than 00 (more preferably, SF2 is 120 or more to 17
5).

The metal oxide has a shape factor SF1 of 150 to 250 (more preferably, SF1 of 160 to 23).
0), and the shape factor SF2 is preferably 160 or more and 300 (more preferably, SF2 is 175 to 270).

In order to exhibit each of the above effects, the particle size of each external additive is defined, and the sphericity (SF
1) The present inventors have found that it is important to define the degree of unevenness (SF2) as a result of intensive studies. The degree of sphericity and the degree of unevenness greatly affect the cleaning property of the cleaning member and the performance of removing adhering matter.

The resin fine particles preferably have a spherical shape and a certain degree of unevenness, are hardly taken into the cleaner by the cleaning member, are present at the contact portion between the cleaning member and the electrostatic image carrier, and Increases cleaning properties of toner and the like. Further, since the toner has a spherical shape, the toner and the like are collected on the charging member by slipping through the cleaning member to some extent, thereby preventing the electrostatic image carrier from being damaged.

As the metal oxide, those having a certain degree of sphericity and irregularity and exhibiting an irregular shape are preferable, and those having a spherical shape are inferior in the ability to remove adhered substances, are more likely to pass through the cleaner member, and cause image defects. This tends to cause chipping of the electrostatic image carrier.

The shape factors SF1 and SF2 are obtained from Hitachi F
Using E-SEM (S-800), 10 images of the external additives within the range of the average particle size of the present invention magnified 30,000 to 60,000 times are sampled at random, and the image information is used as an interface. Through a Nicole image analysis device (Luzex3) for analysis and calculation by the following equation.

[0042]

[Outside 1] (Where MXLNG is the absolute maximum length of the particle, PERIME
Is the perimeter of the grain, and AREA is the projected area of the grain. )

The specific surface area of the inorganic fine powder is 70 to 300 m ^2.
/ G (more preferably 70 to 150 m ² / g), the specific surface area of the resin fine particles is 5.0 to 20.0 m ² / g (more preferably 8.0 to 15.0 m ² / g), The specific surface area is preferably from 0.5 to 10.0 m ² / g.

If the specific surface area of the inorganic fine powder is smaller than 70 m ² / g, the probability of existence as a free substance increases, which tends to cause uneven distribution of the inorganic fine powder and generation of black spots due to aggregates. If it is larger than 300 m ² / g, the hygroscopicity of the toner increases, and the environmental stability of the developer decreases. When the specific surface area of the resin fine particles is smaller than 5.0 m ² / g, the amount of adsorbing the released inorganic fine powder decreases. 20.0 m ² / g
If it is larger than this, it is difficult to sufficiently reduce the shaving of the electrostatic image carrier by the metal oxide. When the specific surface area of the metal oxide is smaller than 0.5 m ² / g, the surface of the electrostatic image carrier and the developer carrier become remarkable. 1
If it is more than 0.0 m ² / g, it may not be possible to remove the deposits on the surface of the electrostatic image carrier, or it may pass through the cleaning member and lead to image defects.

The volume resistivity of the fine resin particles is 10 ⁷
〜１０10 ¹⁴ Ωcm (more preferably 10 ⁸ 〜１０10 ¹⁴ Ωc
m) is preferred. The volume resistivity of the resin fine particles is 10 ⁷
Low and may not charge quantity sufficient toner is obtained than [Omega] cm, free prone to leakage of charge when adhering to the electrostatic charge image bearing member surface, 10 ¹⁴ large, the toner is charged up than [Omega] cm And the image density tends to decrease.

The amount of the inorganic fine powder to be added to the toner is 0.1.
3 to 3.0% by weight, the added amount of the resin fine particles is 0.005 to 0.5% by weight based on the toner, and the added amount of the metal oxide is 0.05 to 5.0 based on the toner. % By weight (more preferably 0.05 to 2.0% by weight).

When the addition amount of the inorganic fine powder is less than 0.3% by weight, the cohesiveness of the toner increases, and when it exceeds 3.0% by weight, charge-up tends to occur. If the amount of the resin fine particles is less than 0.005% by weight, the polishing force of the metal oxide cannot be reduced in a well-balanced manner. If the amount is more than 0.5% by weight, poor cleaning tends to occur and the charging roller tends to be stained. When the addition amount of the metal oxide is less than 0.05% by weight, the polishing force on the electrostatic image carrier is weak, and the weight is 5.0% by weight.
If the amount is larger than the above range, the electrostatic image carrier tends to be cut more than necessary and unevenly.

Particularly preferred among the inorganic fine powders used in the present invention are those produced from dry silica called dry process or fumed silica, produced by vapor phase oxidation of a silicon halide, and water glass. Both so-called wet silicas can be used. Above all, there are few silanol groups on the surface and inside the silica fine powder,
Further, dry silica having no production residue such as Na ₂ O and SO ₃ ^2- is more preferable. In the case of fumed silica, it is also possible to obtain a composite fine powder of silica and another metal oxide by using another metal halide such as aluminum chloride or titanium chloride together with a silicon halide in the production process. In the present invention, the inorganic fine powder also includes them.

The average particle size of the inorganic fine powder is preferably in the range of 0.001 to 2 μm, more preferably 0.002 to 0.2 μm. Good to use.

The inorganic fine powder used in the present invention is preferably hydrophobic in view of environmental stability.

For the hydrophobizing treatment, conventionally known hydrophobizing agents and methods are used. As the hydrophobizing agent, a silicone compound having an organosiloxane unit such as silicone oil or silicone varnish is preferably used, and silicone oil is particularly preferred from the viewpoint of fluidity and chargeability of the toner.

The silicone oil used in the treatment of the inorganic fine powder used in the present invention is represented by the general formula

[0053]

[Outside 2] [R represents an alkyl group having 1 to 3 carbon atoms, R 'represents an alkyl group, a halogen-modified alkyl group, a phenyl group or a silicone oil-modified group such as a modified phenyl;
Represents an alkyl group or an alkoxy group having 1 to 3 carbon atoms, and m and n each represent an integer.]. Examples thereof include dimethyl silicone oil, alkyl-modified silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, and fluorine-modified silicone oil. The silicone oil is not limited to the above formula.

The silicone oil preferably has a viscosity at a temperature of 25 ° C. of 50 to 1000 centistokes. If it is less than 50 centistokes, it is partially volatilized by the application of heat, and the charging characteristics are likely to deteriorate. 1000
If it exceeds centistokes, handling becomes difficult due to the processing operation. As a method of silicone oil treatment,
Known techniques can be used. For example, silica fine powder and silicone oil are mixed using a mixer; silicone oil is sprayed into fine silica powder using a sprayer; or silicon fine powder is dissolved after dissolving silicone oil in a solvent. Are mixed. The processing method is not limited to this.

As the silicone varnish for treating the fine silica powder used in the present invention, known substances can be used.

For example, KR-25 manufactured by Shin-Etsu Silicone Co., Ltd.
1, KP-112 and the like, but are not limited thereto.

As the method of the silicone varnish treatment, the same known technique as the oil treatment can be used.

A part of the silicon compound having an organosiloxane unit treating the surface of the inorganic fine powder is transferred to the electrostatic image carrier, and has an effect of further facilitating cleaning of the powder such as free polyolefin. .

The degree of hydrophobicity of the inorganic fine powder in the present invention is as follows:
It is measured by the following method. Of course, other measurement methods are possible with reference to the measurement method of the present invention.

100 ml of ion-exchanged water and 0.1 g of a sample are placed in a sealed stopper 200 ml separating funnel, and the mixture is shaken at 90 rpm with a shaking machine (Tavla shaker mixer T2C type).
Shake for 10 minutes. After shaking, the mixture was allowed to stand for 10 minutes, and after the inorganic powder layer and the aqueous layer were separated, the lower aqueous layer was separated for 20 minutes.
~ 30ml, put into a 10mm cell, 500nm
The transmittance is measured with reference to the ion-exchanged water of a blank not containing the inorganic fine powder at the wavelength described above, and the value of the transmittance is used as the degree of hydrophobicity of the inorganic fine powder.

The hydrophobic inorganic fine powder of the present invention preferably has a degree of hydrophobicity of 60% or more (more preferably 90% or more). When the degree of hydrophobicity is less than 60%, it is difficult to obtain a high-quality image due to moisture adsorption of the inorganic fine powder under high humidity.

An example of the measurement of the volume resistivity of the resin fine particles in the present invention will be described. The sample 41 is formed into a tablet using the tablet forming apparatus shown in FIG. At first, about 0.3
g is put into the tablet molding chamber 43. Next, the push rod 42 is inserted into the tablet molding chamber 43,
g / cm ² for 5 minutes, diameter about 13mm, height about 2
Mold tablets in pellet form of ~ 3 mm. 44 is a pressure gauge.

The tablets obtained here are coated with a conductive agent on the front surface and the back surface as required, for example, HEWLETT.
16008A RESISTIVIT manufactured by PAKARD
YCELL; or 4329A HIGH RE manufactured by the company
Temperature 23.5 using SISTANCE METER
A resistance value when a voltage of 1000 V is applied is measured in an environment at a temperature of 65 ° C. and a humidity of 65% RH, and a volume specific resistance value ρ is obtained by calculation.

[0064]

[Outside 3] (Where S is the cross-sectional area of the sample and 1 is the height of the sample)

The resin fine particles can be produced by adjusting production conditions by an emulsion polymerization method or a spray drying method. Preferably, resin particles having a glass transition point of 80 ° C. or higher obtained by homopolymerizing or copolymerizing monomers used for a binder resin for a toner such as styrene, acrylic acid, methyl methacrylate, butyl acrylate, and 2-ethylhexyl acrylate by an emulsion polymerization method. Shows a good effect.

The surface may be cross-linked with a cross-linking agent such as divinylbenzene, and the surface may be treated with a metal, metal oxide, pigment, dye, surfactant or the like to adjust the volume resistivity and triboelectric charge. good.

The resin fine particles in the present invention are particularly preferably block or random styrene-based copolymers containing 51% by weight or more of styrene-based monomer units.
The styrene-based resin fine particles generally have a similar charging sequence to a styrene-acrylic resin or a polyester resin used as a binder resin of the toner, have little mutual charge with the toner particles, and do not easily deteriorate in fluidity. Therefore, a styrene resin is preferable as the binder resin of the toner.

If the styrene monomer unit content in the resin fine particles is less than 51% by weight, the cohesiveness of the toner is increased, the fluidity is deteriorated, and image blanking and image density unevenness are likely to occur.

Examples of the metal oxide include oxides such as magnesium, zinc, aluminum, cobalt, zirconium, manganese, cerium and strontium; composite metal oxides such as calcium titanate, magnesium titanate, strontium titanate and barium titanate Is mentioned. Of these, strontium titanate and cerium oxide are most preferred from the viewpoint of the abrasiveness of the electrostatic image carrier and the chargeability of the toner.

In the present invention, the specific surface area of the hydrophobic silica, the resin fine particles and the metal oxide can be determined, for example, by using a fully automatic gas adsorption amount measuring apparatus: Autosorb 1, manufactured by Yuasa Ionics Co., Ltd. And by the BET multipoint method. The pretreatment of the sample was performed at 50 ° C.
For 10 hours.

The chargeability of the toner, hydrophobic silica, fine resin particles and metal oxide can be determined, for example, by the polarity of a two-component tribo using an iron powder carrier.

Further, according to the present invention, the polymer component of the toner is
(A) substantially free of a THF-insoluble component, and (b) a THF-soluble component of a polymer component is represented by a GPC chromatogram.
(C) having an acid value of 1 mgKOH / g or more, having a main peak in a region of a molecular weight of 3 × 10 ^{3 to} 3 × 10 ⁴ , a subpeak or a shoulder in a region of a molecular weight of 1 × 10 ^{5 to} 3 × 10 ⁶ , It is preferable to have

Furthermore, the present invention relates to the acid value (A _VL ) of the low molecular weight polymer (region having a molecular weight of less than 5 × 10 ⁴ in the GPC chromatogram) of the polymer component of the toner and the high molecular weight polymer (GPC chromatogram). In this case, it is preferable that the acid value (A _VH ) having a molecular weight of 5 × 10 ⁴ or more satisfies the following condition: A _VL > A _VH .

Further, according to the present invention, the acid value (A _VL ) of the low molecular weight polymer of the polymer component is 21 to 35 mgKOH / g, and the acid value (A _VH ) of the high molecular weight polymer is 0.5 to 0.5 mg KOH / g. 11
mg KOH / g, and the relationship of the difference is preferably 10 ≦ (A _VL −A _VH ) ≦ 27.

Further, in the present invention, the ratio of the acid value / total acid value of the polymer component is preferably 0.7 or less.

Further, the present invention relates to a GPC chromatogram of a THF-soluble portion of the polymer component, which has a molecular weight of 3 × 10 ⁴
It is preferable to have a local minimum value in a region of less than 1 × 10 ⁵ .

Next, the various conditions of the polymer component of the toner will be described in detail.

It is preferable that the polymer component of the toner of the present invention does not substantially contain a THF-insoluble component. In particular,
It is more preferable that the content be 5% by weight or less, preferably 3% by weight or less based on the resin composition.

The THF-insoluble matter indicates the weight ratio of the polymer component (substantially cross-linked polymer) insoluble in the THF solvent in the resin composition in the toner, and indicates the cross-linking of the resin composition containing the cross-linking component. Can be used as a parameter to indicate the degree of The THF-insoluble matter is defined by a value measured as follows.

0.5 to 1.0 g of the toner sample is weighed (w ₁ g), and the sample is filtered with a cylindrical filter paper (for example, No. 86 manufactured by Toyo Filter Paper Co., Ltd.).
R) and run through a Soxhlet extractor, where T
After extracting with 100 to 200 ml of HF for 6 hours and evaporating the soluble component extracted with the solvent, 10
After vacuum drying for several hours at 0 ° C., the amount of the THF-soluble resin component is weighed (w ₂ g). The weight of a component other than the resin component such as a magnetic substance or a pigment in the toner is defined as (w ₃ g). THF
The insoluble content is obtained from the following equation.

THF insoluble matter (%) = [｛w ₁ − (w ₃ + w)
₂ )｝ / (w ₁ -w ₃ )] × 100 If the content of THF insolubles exceeds 5% by weight, the fixability is deteriorated.

The T of the polymer component in the toner composition of the present invention
The chromatogram of GPC measured by the HF soluble component is 3 × 10 ^{3 to} 3 × 10 ⁴ (more preferably 5 × 10 ^3).
× 10 ^{3 to} 2 × 10 ⁴ ), and has a main peak and a molecular weight of 1 × 10 ^{5 to} 3 × 10 ⁶ (more preferably ⁵ × 10 ^{3 to} 2 × 10 ⁴ ).
It is preferable to have a sub-peak or a shoulder in a region of × 10 ⁵ to 1 × 10 ⁶ ).

In the GPC chromatogram, a polymer component having a molecular weight of 1,000,000 or more is preferably present in an area ratio of 3% or more (more preferably 3 to 10%). 3% of components soluble in THF with a molecular weight of 1,000,000 or more
By virtue of the above, offset resistance can be improved without hindering low-temperature fixing, and at the same time, storage stability of the toner when left at high temperatures can be improved.

In the present invention, the molecular weight distribution of the polymer component of the resin composition of the toner is measured by GPC (gel permeation chromatography) under the following conditions.

Conditions for GPC measurement of resin composition and polymer : GPC-150C (manufactured by Waters) Column: KF801 to 7 (manufactured by Shodex) Temperature: 40 ° C. Solvent: THF (tetrahydrofuran) Flow rate: 1 .0 ml / min. Sample: 0.1 m of a sample having a concentration of 0.05 to 0.6% by weight
l injection

In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of the calibration curve prepared from several types of monodisperse polystyrene standard samples and the count number. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical
Co. Or Toyo Soda Kogyo Co., Ltd. with a molecular weight of 6
× 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 1
0 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ ,
8.6 × 10 ⁵ , 2 × 10 ⁶ , and 4.48 × 10 ⁶ are used. It is appropriate to use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector.

In the present invention, the polymer component of the toner is 1 m
It preferably has an acid value of at least gKOH / g (more preferably at least 2 mgKOH / g). 1m polymer component
By having an acid value of gKOH / g or more, charging of the toner is stabilized, and long-term durability is improved.

[0088] polymer component used in the present invention preferably has a relationship of the acid value of the low molecular weight polymer (A _VL) and high molecular weight polymer of acid value (A _VH) is A _VL> A _VH More preferably, the acid value (A _VH ) of the low molecular weight polymer is 21 to
5 mg KOH / g, the acid value (A _VH ) of the high molecular weight polymer is 0.5 to 11 mg KOH / g, and the relation of the difference is 10 ≦ (A _VL −A _VH ) ≦ 27. Is preferred.

As a result of intensive studies, the present inventors have found that, in a toner resin composition composed of a low molecular weight polymer and a high molecular weight polymer, each of the polymer components having the acid value shown above has low-temperature fixability, It has been found that it is effective for offset resistance, prevention of toner sticking to an electrostatic image carrier, and further improvement of developability.

The low-temperature fixability is determined by the Tg of the low molecular weight polymer component.
And the molecular weight distribution is dominant, but the acid component is contained in this component, and furthermore, the acid value is higher than the acid value of the high molecular weight polymer component by 1%.
By increasing it by 0 mgKOH / g or more, the same T
g and a resin composition having the same molecular weight distribution and an acid value out of the above range can lower the viscosity.

This is because the acid value of the high molecular weight polymer component is set at least 10 mg KOH / g lower than the acid value of the low molecular weight polymer component (acid value 0.5 to 11 mg KOH / g), whereby the low molecular weight polymer component is obtained. It is considered that the entanglement of the molecular chains of the high molecular weight polymer component and the high molecular weight polymer component is suppressed to some extent, and therefore, lowering the viscosity on the low temperature side and maintaining the elastic properties on the high temperature side are achieved. This also leads to low-temperature fixing in a high-speed machine and improvement in developing characteristics.

On the other hand, the difference in acid value is 27 mgKOH / g
If the ratio exceeds the above range, the miscibility of the low-molecular-weight polymer component and the high-molecular-weight polymer component will be impaired, and the durability offset property and the developability will tend to be reduced.

Further, the acid value of the low molecular weight polymer component is 21
When it is not less than mgKOH / g, the rising property of charging is good.

On the other hand, the acid value of the low molecular weight polymer component is 35 m
If it exceeds gKOH / g, environmental characteristics, particularly, developability under high humidity may be impaired.

The acid value of the high molecular weight polymer component is 0.5 mgK
If it is less than OH / g, the low molecular weight polymer component (acid value 2
1-3-35 mg KOH / g), and
In some cases, the developability, particularly the fog characteristics, may be deteriorated.

The polymer component has an acid value / total acid value ratio of 0.7 or less (more preferably 0.4 to 0.6).
Is more preferable. The value of acid value / total acid value is 0.
If it exceeds 7, the balance of charging of the toner, that is, the balance of charging and discharging, tends to be charged, and the toner charging stability tends to be reduced.

The polymer component is THF as the polymer component.
In the GPC chromatogram of the soluble portion, the molecular weight was 3 × 10
It is preferable to have a minimum value (Min) in a region of ⁴ or more and less than 1 × 10 ⁵ . In order to achieve both low-temperature fixability and high-temperature offset resistance, it is preferable that the low-molecular-weight polymer component and the high-molecular-weight polymer component have independent molecular weight distributions.

[0098] polymer components of the toner resin composition of the present invention, in relation to the low molecular weight polymer component and a high molecular weight polymer component with respect to the mixing _{ratio, W L: W H = 50} : 50~90: 10 Is preferably satisfied. The reason is that if the ratio of the low molecular weight polymer component to the high molecular weight polymer component is out of this range, the fixability and the offset resistance are likely to be reduced. That is, when the content of the low molecular weight polymer component is less than 50% by weight, the fixing property is liable to decrease, while the content of the high molecular weight polymer component is 10%.
If the amount is less than% by weight, the high-temperature offset resistance tends to decrease.

Further, with respect to the relationship between the mixing amount and the acid value,

[0100]

[Outside 4] Is preferably satisfied. The reason is that when the mixing amount of the low molecular weight component and the high molecular component and their respective acid values do not satisfy the relationship of the above formula,

[0101]

[Outside 5] When the acid value of the low molecular weight component in the entire resin is lower than 4 times the acid value of the high molecular weight component in the entire resin, the mixing property between the low molecular weight component and the high molecular component increases, and the low viscosity at low temperature side is improved. It tends to be more difficult to emphasize high elasticity on the high temperature side.

Also,

[0103]

[Outside 6] Is less than 11, the rising characteristics of charging are deteriorated. On the other hand, when it is more than 30, the developability under high humidity tends to decrease.

In the present invention, the acid value (JIS acid value) of the low molecular weight polymer component and the high molecular weight polymer component of the toner polymer component
Is determined by the following method.

[0105] prep device configuration LC-908 of each component (Japan Analytical Industry Co., Ltd.) JRS-86 (the company; repeat injector) JAR-2 (the company; autosampler) FC-201 (Gilson; hula cushion collector) [Column configuration] JAIGEL-1H to 5H (diameter 20 mm x 600 m
m: Preparative column) Measurement conditions Temperature: 40 ° C. Solvent: THF Flow rate: 5 ml / min. Detector: The RI sample separates additives other than the polymer component in advance.
As a preparative method, an elution time at which the molecular weight becomes 5 × 10 ⁴ is measured in advance, and before and after the elution time, the low molecular weight polymer component and the high molecular weight polymer component are separated. The solvent is removed from the sampled sample to obtain a sample for acid value measurement.

Measurement of Acid Value (JIS Acid Value) 1) A crushed sample of 0.1 to 0.2 g is precisely weighed, and its weight is defined as W (g). 2) The sample is placed in a 20 cc Erlenmeyer flask, and 10 cc of a mixed solution of toluene / ethanol (2: 1) is added and dissolved. 3) Add a few drops of phenolphthalein alcohol solution as indicator. 4) Using an alcohol solution of 0.1 N KOH, titrate the solution in the flask with a burette. The amount of the KOH solution at this time is defined as S (ml). At the same time, a blank test is performed, and the amount of the KOH solution at this time is defined as B (ml). 5) Calculate the acid value by the following equation.

[0107]

[Outside 7]

The measurement of the total acid value in the present invention is carried out as follows.

Measurement of total acid value 1) A sample is used after removing additives other than the polymer component in advance. About 2 g of the crushed sample is precisely weighed, and its weight is W ′.
(G). 2) The sample is placed in a 200 cc Erlenmeyer flask, and 30 cc of 1,4-dioxane, 10 cc of pyridine and 20 mg of 4-dimethylaminopyridine are added and dissolved for 1 hour. 3) Add 3.5 cc of ion-exchanged water and reflux for 4 hours. Then cool. 4) Add a few drops of phenolphthalein alcohol solution as indicator. 5) Titrate the solution in the flask using a 0.1 N KOH THF solution using a burette. KO at this time
Let the amount of H solution be S '(ml). At the same time, a blank test is performed, and the amount of the KOH solution at this time is defined as B ′ (ml). 6) Measure the total acid value according to the following equation.

[0110]

[Outside 8] As a KOH THF solution, 6.6 g of KOH was added to and dissolved in 20 cc of ion-exchanged water, and then 720 cc of THF was added.
Add 100 cc of ion-exchanged water, and then add methanol with stirring until it becomes transparent.

Examples of the monomer for adjusting the acid value of the polymer component of the present invention include acrylic acid such as acrylic acid, methacrylic acid, α-ethylacrylic acid and crotonic acid and α-acrylic acid thereof.
Alternatively, there are β-alkyl derivatives; unsaturated dicarboxylic acids such as fumaric acid, maleic acid and citraconic acid, and their monoester derivatives or maleic anhydride. Such a monomer can be used alone or as a mixture and copolymerized with another monomer to produce a desired polymer.
Among them, it is particularly preferable to use a monoester derivative of an unsaturated dicarboxylic acid for controlling the acid value / total acid value.

More specifically, monomethyl maleate, monoethyl maleate, monobutyl maleate, monooctyl maleate, monoallyl maleate, monophenyl maleate, monomethyl fumarate, monomethyl fumarate, monoethyl fumarate,
Monoesters of α, β-unsaturated dicarboxylic acids such as monobutyl fumarate and monophenyl fumarate; monobutyl n-butenylsuccinate, monomethyl n-octenylsuccinate, monoethyl n-butenylmalonate, n-dodecenylglutaric acid Monoesters of alkenyl dicarboxylic acids such as monomethyl and monobutyl n-butenyl adipate; monoesters of aromatic dicarboxylic acids such as monomethyl phthalate, monoethyl phthalate and monobutyl phthalate;

The carboxyl group-containing monomer as described above may be added in an amount of 1 to 20% by weight, preferably 3 to 15% by weight, based on all monomers constituting the polymer side of the binder resin.

The reason why the monoester monomer of dicarboxylic acid is selected is that, in the suspension polymerization, it is not appropriate to use an acid monomer having high solubility in an aqueous suspension, and This is because it is preferably used in a low ester form.

In the present invention, the carboxylic acid groups and carboxylic acid ester sites in the copolymer obtained by the above method can be saponified by alkali treatment. It is preferable that the carboxylic acid group or the carboxylic acid ester site is changed to a polar functional group by reacting with a cation component of an alkali. Even if the polymer side component of the binder resin contains a carboxyl group that reacts with the metal-containing compound,
This is because if the carboxyl group is dehydrated, that is, the ring is closed, the efficiency of the crosslinking reaction decreases.

This alkali treatment may be carried out after the production of the binder resin, by introducing it as an aqueous solution into the solvent used at the time of polymerization and stirring. Examples of the alkali that can be used in the present invention include Na, K, Ca, Li, Mg, and Ba.
Hydroxides of alkali metals and alkaline earth metals such as;
Hydroxides of transition metals such as Zn, Ag, Pb, and Ni; and hydroxides of quaternary ammonium salts such as ammonium salts, alkylammonium salts, and pyridium salts. Particularly preferred examples include NaOH and KOH.

In the present invention, the saponification reaction does not need to be carried out over all of the carboxylic acid groups and carboxylic acid ester sites in the copolymer. I just need to change.

The amount of the alkali used in the saponification reaction is difficult to determine unconditionally depending on the type of the polar group in the binder resin, the dispersion method, the type of the constituent monomers, and the like. What is necessary is just 5 times equivalent.
When the amount is less than 0.02 equivalent, the saponification reaction is not sufficient, and the number of polar functional groups generated by the reaction decreases,
As a result, the subsequent crosslinking reaction becomes insufficient. On the other hand, when the amount exceeds 5 times equivalent, the functional group such as the carboxylic acid ester site is adversely affected by hydrolysis of the ester, generation of a salt by a saponification reaction, and the like.

When an alkali treatment of 0.02 to 5 times equivalent of the acid value is performed, the residual cation concentration after the treatment is 5 to 100%.
It is contained between 0 ppm and can be preferably used to regulate the amount of alkali.

The resin composition according to the present invention has a glass transition temperature (Tg) of 50 to 70 ° C., preferably 55 to 65 ° C. from the viewpoint of storage stability. Tends to cause deterioration of the toner and offset at the time of fixing. On the other hand, when Tg exceeds 70 ° C., the fixability tends to decrease.

The relationship between Tg _L of the low molecular weight polymer component and Tg _H of the high molecular weight polymer component of the resin composition according to the present invention is preferably in the range of Tg _L ≧ Tg _H -5 (° C.) If Tg _L is less than Tg _H -5, there is a tendency that developing property lowers. More preferably, Tg _L ≧ Tg _H is good.

As a method for producing the binder resin used in the present invention, a high molecular weight polymer and a low molecular weight polymer are separately synthesized by a solution polymerization method, and then they are mixed in a solution state.
Next, a solution blending method in which the solvent is removed; a dry blending method in which the mixture is melt-kneaded by means such as an extruder; , Washing with water and drying to obtain a resin composition. However, the dry blending method has problems in terms of uniform dispersion and compatibility, and the two-stage polymerization method has many advantages in uniform dispersibility, but the low molecular weight polymer component is more than the high molecular weight polymer component. In the presence of a low molecular weight polymer component, not only is it difficult to synthesize a high molecular weight polymer component having a large molecular weight, but also unnecessary by-products of a low molecular weight polymer component are generated. Therefore, to apply to the present invention,
The solution blending method is most preferred.

As a method for synthesizing the high molecular weight component of the resin composition used in the present invention, a solution polymerization method, an emulsion polymerization method or a suspension polymerization method can be used as a polymerization method that can be used in the present invention.

Among them, the emulsion polymerization method is a method in which a monomer (monomer) almost insoluble in water is dispersed as small particles in an aqueous phase with an emulsifier, and polymerization is carried out using a water-soluble polymerization initiator. . In this method, the reaction heat can be easily adjusted, and the phase in which the polymerization is performed (oil phase composed of a polymer and a monomer)
And the aqueous phase are separate, so that the termination reaction rate is low, resulting in a high polymerization rate and a high degree of polymerization. Further, due to the relatively simple polymerization process and the fact that the polymerization product is fine particles, in the production of toner,
There is an advantage as a method for producing a binder resin for a toner because it is easy to mix with a colorant, a charge control agent and other additives.

However, the resulting polymer tends to be impure due to the added emulsifier, and an operation such as salting out is required to remove the polymer. To avoid this inconvenience, suspension polymerization is convenient.

In the suspension polymerization, 100 parts by weight or less of the monomer (preferably 1 part by weight) is added to 100 parts by weight of the aqueous solvent.
(0 to 90 parts by weight). Examples of usable dispersants include polyvinyl alcohol, partially saponified polyvinyl alcohol, and calcium phosphate, and are generally used in an amount of 0.05 to 1 part by weight based on 100 parts by weight of the aqueous solvent. The polymerization temperature is suitably from 50 to 95 ° C, but should be appropriately selected depending on the initiator used and the intended polymer.

The high molecular weight polymer component of the resin composition used in the present invention is used alone or in combination with a monofunctional polymerization initiator as exemplified below in order to achieve the object of the present invention. I do.

Specific examples of the polyfunctional polymerization initiator having a polyfunctional structure include 1,1-di-t-butylperoxy-
3,3,5-trimethylcyclohexane, 1,3-bis- (t-butylperoxyisopropyl) benzene,
2,5-dimethyl-2,5- (t-butylperoxy)
Hexane, 2,5-dimethyl-2,5-di- (t-butylperoxy) hexyne-3, tris- (t-butylperoxy) triazine, 1,1-di-t-butylperoxycyclohexane, , 2-Di-tert-butylperoxybutane, 4,4-di-tert-butylperoxyvaleric acid-n-butyl ester, di-tert-butylperoxyhexahydroterephthalate, di-tert-butylperoxy Azelate, di-t-butylperoxytrimethyl adipate, 2,2-bis- (4,4-di-t-
Butylperoxycyclohexyl) propane, 2,2-
a polyfunctional polymerization initiator having a functional group having a polymerization initiation function such as two or more peroxide groups in one molecule such as t-butylperoxyoctane and various polymer oxides, and diallyl peroxydicarbonate; In one molecule such as butylperoxymaleic acid, t-butylperoxyallyl carbonate and t-butylperoxyisopropyl fumarate, both a functional group having a polymerization initiation function such as a peroxide group and a polymerizable unsaturated group are contained. Having a polyfunctional polymerization initiator.

Among these, more preferred are 1,1
-Di-tert-butylperoxy-3,3,5-trimethylcyclohexane, 1,1-di-tert-butylperoxycyclohexane, di-tert-butylperoxyhexahydroterephthalate, di-tert-butylperoxyase And 2,2-bis- (4,4-di-t-butylperoxycyclohexyl) propane, and t-butylperoxyallyl carbonate.

These polyfunctional polymerization initiators are preferably used in combination with a monofunctional polymerization initiator in order to satisfy various performances required as a binder for a toner.
Particularly, it is preferable to use the polyfunctional polymerization initiator together with a polymerization initiator having a decomposition temperature lower than the decomposition temperature for obtaining a half-life of 10 hours.

Specifically, benzoyl peroxide,
1,1-di (t-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-di (t
-Butylperoxy) valerate, dicumyl peroxide, α, α'-bis (t-butylperoxydiisopropyl) benzene, t-butylperoxycumene, di-t
Organic peroxides such as -butyl peroxide, azo and diazo compounds such as azobisisobutyronitrile and diazoaminoazobenzene can be used.

These monofunctional polymerization initiators may be added to the monomer at the same time as the above-mentioned polyfunctional polymerization initiator. However, in order to maintain the initiator efficiency of the polyfunctional polymerization initiator properly, It is preferable to add the compound after the half-life of the polyfunctional polymerization initiator has elapsed under any polymerization conditions.

These initiators are preferably used in an amount of 0.05 to 2 parts by weight based on 100 parts by weight of the monomer from the viewpoint of efficiency.

The high molecular weight polymer component of the resin composition used in the present invention is preferably crosslinked with a crosslinkable monomer as exemplified below in order to achieve the object of the present invention. As the crosslinkable monomer, a monomer having two or more polymerizable double bonds is mainly used. Specific examples include aromatic divinyl compounds (eg, divinylbenzene, divinylnaphthalene, etc.); diacrylate compounds linked by an alkyl chain (eg, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4 -Butanediol diacrylate, 1,
5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, and acrylates of the above compounds replaced with methacrylate); diacrylate compounds linked by an alkyl chain containing an ether bond (For example, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, dipropylene glycol diacrylate, and acrylates of the above compounds were replaced with methacrylates) Diacrylate compounds linked by a chain containing an aromatic group and an ether bond [for example, polyoxyethylene (2) -2,2-bis ( - hydroxyphenyl) propane diacrylate, polyoxyethylene (4) -2,
2-bis (4-hydroxyphenyl) propane diacrylate and those obtained by replacing the acrylate of the above compound with methacrylate]; polyester type diacrylate compounds [for example, trade name MANDA (Nippon Kayaku)]. As multifunctional crosslinking agents, pentaerythritol acrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, tetramethylolpropane triacrylate, tetramethylolmethanetetraacrylate, oligoester acrylate, and acrylates of the above compounds to methacrylate Alternatives; triallyl cyanurate, triallyl trimellitate; and the like.

[0135] These cross-linking agents may be used in combination with other monomer components 10
1 part by weight or less, preferably 0.00 part by weight with respect to 0 part by weight
It is preferable to use in the range of 1 to 0.05 part by weight.

Among these crosslinkable monomers, those which are preferably used from the viewpoints of toner fixing property and offset resistance are linked by a chain containing an aromatic divinyl compound (particularly divinylbenzene), an aromatic group and an ether bond. Diacrylate compounds.

On the other hand, as a method for synthesizing the low molecular weight component of the binder resin according to the present invention, a known method can be used. However, in the bulk polymerization method, a polymer having a low molecular weight can be obtained by increasing the termination reaction rate by polymerizing at a high temperature, but there is a problem that the reaction is difficult to control.
In this regard, in the solution polymerization method, a low molecular weight polymer can be easily obtained under mild conditions by utilizing the difference in chain transfer of radicals depending on the solvent, and by adjusting the amount of the initiator and the reaction temperature, It is preferable to obtain a low molecular weight compound in the resin composition used in the present invention. In particular, minimize the amount of initiator used,
From the viewpoint of minimizing the influence of the initiator residue, a solution polymerization method under a pressurized condition is also preferable.

The monomers for obtaining the high molecular weight polymer component and the monomers for obtaining the low molecular weight polymer component include:
Examples include the following:

For example, styrene; o-methylstyrene, m
-Methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene,
2,4-dimethylstyrene, pn-butylstyrene,
styrene and its derivatives such as p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene; ethylene; Of ethylenically unsaturated monoolefins such as propylene, butylene and isobutylene; unsaturated polyenes such as butadiene; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide and vinyl fluoride; vinyl acetate, vinyl propionate and vinyl benzoate. Vinyl esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, methacryl Α-methylene aliphatic monocarboxylic acid esters such as phenyl, dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate; methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-acrylate Acrylates such as octyl, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; vinyl methyl ketone; Vinyl ketones such as vinyl hexyl ketone and methyl isopropenyl ketone; N-vinyls such as N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole and N-vinyl pyrrolidone Vinyl compounds; vinylnaphthalene; acrylic acid derivatives such as acrylonitrile, methacrylonitrile, and acrylamide or methacrylic acid derivatives. These vinyl monomers are used alone or in combination of two or more.

Among these, a combination of monomers that results in a styrene copolymer or a styrene-acrylic copolymer is preferred.

It is preferable from the viewpoint of miscibility that both the low molecular weight and high molecular weight polymer components contain at least 65 parts by weight of a styrene polymer component or a copolymer component.

When the high molecular weight polymer constituting the resin composition used in the present invention is previously mixed with a low molecular weight wax, phase separation in the micro region is reduced, and the high molecular weight component is not re-agglomerated, A good dispersion state with the low molecular weight polymer is obtained.

Examples of the low molecular weight wax applicable to the present invention include polypropylene, polyethylene, microcrystalline wax, carnauba wax, sasol wax, paraffin wax, higher alcohol wax,
Ester waxes and the like; and oxides and graft-modified products thereof.

The weight average molecular weight of these low molecular weight waxes is 30,000 or less, preferably 10,000 or less (more preferably 8 or less).
(0000 to 9000). The addition amount is preferably about 1 to 20 parts by weight based on 100 parts by weight of the binder polymer component.

These low molecular weight waxes may be added to and mixed with the binder polymer component in advance in the production of the toner. In particular, a method of preliminarily dissolving the low molecular weight wax and the high molecular weight polymer in a solvent at the time of preparing the polymer component and mixing the low molecular weight wax with the low molecular weight polymer solution may be used.

The solid concentration of the polymer solution is 5 to 70% by weight in consideration of dispersion efficiency, prevention of deterioration of the resin at the time of stirring, operability, etc. The preliminary solution of the high molecular weight polymer component and the polyolefin polymer is 5 to 60% by weight, low molecular weight polymer solution is 5%
An example is a solids concentration of ７０70% by weight.

The method of dissolving or dispersing the high molecular weight polymer component and the low molecular weight wax is performed by stirring and mixing, and the stirring may be performed in a batch system or a continuous system.

For example, as a method of mixing a low molecular weight polymer solution, 10 to 1000 parts by weight of the low molecular weight polymer solution is added to 100 parts by weight of the solid content of the preliminary solution, followed by stirring and mixing. Can be In this case, a batch type or a continuous type may be used.

Organic solvents used for mixing the solution of the resin composition used in the present invention include benzene, toluene, xylol, Solvent Naphtha No. 1, Solvent Naphtha No. 2
No. 3, Solvent Naphtha 3, cyclohexane, ethylbenzene, Solvesso 100, Solvesso 150, hydrocarbon solvents such as mineral spirits; methanol, ethanol, iso-propyl alcohol, n-butyl alcohol, sec-butyl alcohol, iso-butyl alcohol; Alcohol solvents such as amyl alcohol and cyclohexanol; acetone, methyl ethyl ketone,
Ketone solvents such as methyl isobutyl ketone and cyclohexanone; ester solvents such as ethyl acetate, n-butyl acetate and cellosolve acetate; ether solvents such as methyl cellosolve, ethyl cellosolve, butyl cellosolve and methyl carbitol. Among these, aromatic, ketone-based and ester-based solvents are preferred. Also,
These may be mixed and used.

The method of removing the organic solvent is preferably a method of heating the organic solvent solution of the polymer, removing 10 to 80% by weight of the organic solvent under normal pressure, and removing the remaining solvent under reduced pressure. At this time, the organic solvent solution is preferably maintained at a temperature of not less than the boiling point of the used organic solvent and not more than 200 ° C. Below the boiling point of the organic solvent, not only is the efficiency at the time of solvent distillation low, but also unnecessary shearing force is applied to the polymer in the organic solvent, and the redispersion of each constituent polymer is promoted, and in a micro state, May cause phase separation. On the other hand, when the temperature is higher than 200 ° C., the polymer is depolymerized, an oligomer is generated by molecular cleavage, and impurities are mixed into the resin composition, which is not preferable.

The toner used in the present invention is preferably a magnetic toner containing a magnetic substance. The magnetic substance is preferably a magnetic iron oxide, and further preferably contains a silicon element.

The silicon element content of the magnetic iron oxide used in the magnetic toner is 0.1 to 5.0% by weight, preferably 0.4 to 2.0% by weight (more preferably 0 to 2.0% by weight) based on the iron element. 0.5 to 0.9% by weight).

By containing the silicon element in the magnetic material, the fluidity of the toner is excellent, and as a result, the charging of the toner is stabilized, and the durability of the toner is improved. Further, the toner containing a magnetic material containing a silicon element has a very soft polishing effect on the surface of the latent image carrier, and before the toner is completely fixed on the surface of the latent image carrier, It is appropriately polished and has the effect of improving the durability of the latent image carrier.

The amount of silicon element in the magnetic iron oxide particles was determined by the fluorescence X
The measurement was performed by performing a fluorescent X-ray analysis using a X-ray analyzer SYSTEM3080 (manufactured by RIKEN ELECTRIC INDUSTRY CO., LTD.) According to JIS K0119 "General rules for X-ray fluorescence analysis".

The magnetic iron oxide particles used in the magnetic toner of the present invention are preferably used in an amount of 20 parts by weight to 200 parts by weight based on 100 parts by weight of the binder resin. It is more preferable to use 30 to 150 parts by weight.

In some cases, the magnetic iron oxide particles used in the magnetic toner of the present invention may be treated with a silane coupling agent, a titanium coupling agent, titanate, aminosilane, or an organosilicon compound.

As the colorant of the toner, conventionally known pigments or dyes such as carbon black and copper phthalocyanine can be used.

Examples of the charge control agent for the toner include a metal complex salt of a monoazo dye, a metal complex salt of salicylic acid, alkylsalicylic acid, dialkylsalicylic acid or naphthoic acid in the case of a negative charge control agent; a nigrosine dye, azine Dyes, triphenylmethane dyes and pigments, imidazole compounds, quaternary ammonium salts or polymers having a quaternary ammonium salt in the side chain.
These can be used alone or in combination.

To prepare the toner of the present invention, a polymer component and a pigment, a dye or a magnetic material as a colorant, a charge controlling agent and other additives are sufficiently mixed by a mixer such as a ball mill, and then heated. Melting, kneading, and kneading using a hot kneader such as an extruder, kneader, or extruder to disperse or dissolve the pigments or dyes while the resins are mutually compatible. After cooling and solidifying, pulverize and strictly classify. Then, the toner of the present invention can be obtained.

As another method for obtaining the toner of the present invention, the toner can be produced by a polymerization method. The suspension polymerization toner uniformly dissolves or dissolves the polymerizable monomer, the charge control agent of the present invention, the pigment or dye, the magnetic iron oxide, and the polymerization initiator (and, if necessary, the crosslinking agent and other additives). After dispersing into a monomer composition, the monomer composition or a pre-polymerized version of the monomer composition is mixed with a suitable stirrer in a continuous phase (eg, water) containing dispersion stability. And a polymerization reaction is carried out at the same time to obtain toner particles having a desired particle size.

One example of the image forming apparatus is schematically shown in FIG. 1, and an image forming method will be described based on the schematic.

Reference numeral 1 denotes a rotating drum-shaped electrostatic image carrier, around which a primary charging device 2, an exposure optical system 3, a developing device 4 having a toner carrier 5, a transfer device 9, and a cleaning device 11 are arranged. Have been.

In this image forming apparatus, the surface of the electrostatic image carrier 1 as a photoreceptor is uniformly charged by the primary charging device 2, and the image is exposed to light by the exposure optical system 3. An electrostatic latent image is formed on the surface.

Next, a toner coat layer is formed on the surface of the toner carrying member 5 containing the magnet by the toner layer thickness regulating member 6 based on the constitution of the present invention, and the conductivity of the electrostatic image carrier 1 in the developing section is changed. The electrostatic image formed on the electrostatic image carrier 1 is developed while alternate bias, pulse bias and / or DC bias are applied between the base and the toner carrier 5 by the bias applying means 8.

The developed toner image is conveyed to the transfer paper P, and is transferred electrostatically to the transfer paper P by applying a charge having a polarity opposite to that of the toner from the back surface of the transfer paper P by the transfer device 9 and the voltage applying means 10. .

By passing the transfer paper P on which the toner has been transferred through the heating and pressing roller fixing device 12, a fixed image is obtained.

The magnetic toner remaining on the electrostatic image carrier after the transfer step is removed by the cleaning device 11.
The steps following the primary charging are repeated again.

The electrostatic image carrier used in the present invention has a laminated structure comprising at least a conductive support, a charge generation layer and a charge transport layer, and the surface layer of the electrostatic image carrier has fluorine and / or silicon. It is preferable to have atoms from the viewpoint of prolonging the life and preventing uneven shaving of the surface of the electrostatic image carrier.

Examples of the fluorine compound used in the present invention include known fluorine resins, such as ethylene tetrafluoride,
One or more of ethylene trifluoride, propylene hexafluoride, vinyl fluoride, vinylidene fluoride, ethylene dichloride diethylene chloride, etc., and one or more of these copolymers are appropriately selected. . Also, carbon fluoride can be used.

In the present invention, a block containing a fluorine-based segment synthesized from a polymerization copolymer of a fluorine-based polymer or a non-fluorine-based polymerizable monomer, or a graft polymer, a surfactant, and a macromonomer are used. It can be used alone or in combination with the fluororesin.

Examples of the silicon-based compound include a three-dimensional crosslinked product of monomethylsiloxane, a three-dimensionally crosslinked product of dimethylsiloxane-monomethylsiloxane, an ultrahigh molecular weight polydimethylsiloxane, a block polymer containing a polydimethylsiloxane segment, a graft polymer, a surfactant,
Macromonomers, terminal-modified polydimethylsiloxane and the like 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, the molecular weight thereof is preferably in the range of 3,000 to 5,000,000.

The fine particles are dispersed together with a binder resin as a photosensitive layer composition.

The fluorine compound and the silicon compound used in the present invention account for 50% of the organic photosensitive layer (OPC) composition.
It is preferably used in the following amounts. More preferably 0.5
５０50%.

The presence of fluorine and / or silicon atoms in the surface layer of the electrostatic image carrier has the effect of lowering the energy of the surface of the electrostatic image carrier, making it difficult for the toner to adhere. If the compounding amount is too large, the coefficient of friction with the cleaning member will be too low, and conversely, toner will slip through and cause poor cleaning.

FIG. 5 shows a specific example of the apparatus unit (process cartridge) of the present invention. The device unit at least integrally forms the developing means and the electrostatic image carrier into a cartridge, and the device unit is formed so as to be detachable from a main body of the image forming apparatus (for example, a copying machine, a laser beam printer, or the like).

In this example, a developing means 709, a drum-shaped electrostatic image carrier (photosensitive drum) 1, a cleaner 708 having a cleaning blade 708a, and a primary charger (charging roller) 742 having contact charging means are integrated. The device unit 750 is illustrated.

The developing means 709 has a resilient blade 711 and a magnetic toner 710 in a toner container 760. The magnetic toner 710 is used. During development, a bias is applied between the photosensitive drum 1 and the developing sleeve 704 by a bias from bias applying means. The distance between the photosensitive drum 1 and the developing sleeve 704 is important for a predetermined electric field to be formed in the developing device and for the developing process to be suitably performed.

On the other hand, in the present invention, the hardness of the charging member is preferably set to 60 ° or less, more preferably 55 ° or less by ASKER-C, so that the surface of the charged image bearing member to be charged is weakly pressed. A sufficient contact width for charging can be obtained with pressure, and ozone is less generated. Furthermore, even when a voltage having an AC component is applied to the charging member, noise due to charging is less generated.

The hardness of the charging member is 60 ° with ASKER-C.
As a mode for the following, it is preferable that the lower layer portion is formed of an elastic layer made of a thermoplastic elastomer or a flexible rubber and a conductive layer, or that the lower layer portion is formed of a conductive sponge. .

The upper layer of the charging member in contact with the surface of the electrostatic image carrier has a thickness of 50 to 200 μm made of a high-resistance material.
The layer having a thickness of m is preferable from the viewpoint of obtaining stable chargeability without causing leakage.

Hereinafter, the present invention will be described with reference to specific examples, but the present invention is not limited thereto.

Preparation of Resin Composition (I) Synthesis of Low Molecular Weight Polymer (L-1) 300 parts by weight of xylene was charged into a four-necked flask, and the inside of the vessel was sufficiently purged with nitrogen while stirring. The temperature was raised to reflux.

Under the reflux, a mixture of 75 parts by weight of styrene, 18 parts by weight of n-butyl acrylate, 7 parts by weight of monobutyl maleate and 2 parts by weight of di-tert-butyl peroxide was added dropwise over 4 hours. Thereafter, the mixture was held for 2 hours to complete the polymerization, thereby obtaining a low molecular weight polymer (L-1) solution.

A part of the polymer solution was sampled,
The polymer was dried under reduced pressure, and the obtained low molecular weight polymer (L-1) was obtained.
Was measured for GPC and glass transition point (Tg), as a result, weight average molecular weight (Mw) = 9,600, number average molecular weight (Mn) = 6,000, and peak molecular weight (PMw) =
8,500, Tg = 62 ° C., acid value 23.

The conversion of the polymer at this time was 98%.

Synthesis of high molecular weight polymer (H-1) 180 parts by weight of degassed water and 20 parts by weight of a 2% by weight aqueous solution of polyvinyl alcohol were charged into a four-necked flask, and 70 parts by weight of styrene and acrylic acid were added. 25 parts by weight of n-butyl, 5 parts by weight of monobutyl maleate, 0.005 parts by weight of divinylbenzene, and 2,2-bis (4,4-di-t
A mixed solution of 0.1 part by weight of tert-butylperoxycyclohexyl) propane (half-life 10 hours, temperature: 92 ° C.) was added, and stirred to form a suspension.

After sufficiently replacing the inside of the flask with nitrogen, 8
The temperature was raised to 5 ° C. to initiate polymerization. After maintaining at the same temperature for 24 hours, 0.1 part by weight of benzoyl peroxide (half-life of 10 hours; temperature of 72 ° C.) was additionally added. Further, the polymerization was completed by holding for 12 hours.

To the suspension after the completion of the reaction, an aqueous NaOH solution equivalent to 6 times the acid value (AV = 7.8) of the obtained high molecular weight polymer (H-1) was added, and the mixture was stirred for 2 hours. Was.

The high molecular weight polymer (H-1) was separated by filtration, washed with water, dried, and analyzed.
Mw = 1.2 million, Tg = 62 ° C., acid value 7

Preparation of Resin Composition Into a four-necked flask, 100 parts by weight of xylene, 25 parts by weight of the high molecular weight polymer (H-1) and 4 parts by weight of a low molecular weight polypropylene wax (Mw = 6000) were charged.
The mixture is heated and stirred under reflux to perform preliminary dissolution. After maintaining in this state for 12 hours, a uniform pre-dissolved solution of the high molecular weight polymer (H-1) and the low molecular weight polypropylene wax (Y-
1) was obtained.

A part of the pre-dissolved solution was sampled,
The solid was dried under reduced pressure and the glass transition point of the obtained solid was measured.

On the other hand, the low-molecular-weight polymer (L-
300 parts by weight of the homogeneous solution of 1) is introduced and refluxed.

After the above pre-dissolved solution (Y-1) and the low molecular weight polymer (L-1) solution were mixed under reflux, the organic solvent was distilled off, and the obtained resin was cooled, solidified and pulverized. A toner resin composition (I) was obtained.

Analysis of the resin composition (I) showed that P
G of resin composition having Mw = 11.1 million and molecular weight of 1,000,000 or more
The area ratio in the molecular weight distribution of PC is 9.5%, and Tg = 6.
At 2.3 ° C., the THF insoluble matter (excluding low molecular weight polypropylene wax) was 2.0% by weight.

Example 1 (Toner Production Example 1) 100 parts by weight of resin composition (I) 100 parts by weight of magnetic material (containing 0.8% silicon (based on iron element), average particle size 0.2 μm) 100 parts by weight Negative chargeability Control agent (azo-based iron complex) 3 parts by weight The above materials are melt-kneaded with a biaxial extruder heated to 140 ° C, the cooled kneaded material is coarsely pulverized by a hammer mill, and the coarsely pulverized material is finely pulverized by a jet mill. Then, the obtained finely pulverized powder was classified by a fixed wall air classifier to produce a classified powder. In addition, the obtained classified powder is multi-divided using the Coanda effect (Nippon Mining Co., Ltd. elbow jet classifier)
Then, ultrafine powder and coarse powder are strictly classified and removed at the same time, and the content of magnetic toner particles having a weight average particle diameter (D ₄ ) of 6.5 μm (particle diameter of 12.7 μm or more: 0.2%, particle diameter of 3. (Number% of 17 μm or less: 12.0%) to obtain negatively chargeable magnetic toner particles.

The magnetic toner particles had a low molecular weight side peak value of 8200 and a high molecular weight side peak value of 67 according to GPC measurement.
10,000, A _VL = 23, A _VH = 7, acid value / total acid value = 0.44.

In the above magnetic toner particles, 1.2% by weight of inorganic fine powder (hydrophobic silica) A-1 shown in Table 1, 0.08% by weight of resin fine particles B-1 shown in Table 2, and Table 3 1.5% by weight of the metal oxide C-1 shown below was mixed with a Henschel mixer, respectively, to prepare a toner I for electrostatic image development shown in Table 4. Each of the metal oxides shown in Table 3 was pulverized by a sand mill as required to obtain desired particle sizes and shapes.

Examples 2 to 4 (Production Examples 2 to 4 of Toner ) Inorganic fine powder, resin fine particles, and metal oxide of toner I were represented by A-1 and B-2 shown in Table 1 and B-1 and B-1 shown in Table 2, respectively. 2. Toners II to VI for electrostatic image development shown in Table 4 were prepared in the same manner as in Production Example 1 except that C-1 and C-2 shown in Table 3 were used.

Example 5 (Production Example 5 of Toner) A resin composition (I) was used as a styrene-n-butyl acrylate copolymer, and inorganic fine powder, resin fine particles, and metal oxide were respectively A-3, B-5, C-2, and toner V shown in Table 4 was prepared in the same manner as in Production Example 1. This toner is G
The peak value on the low molecular weight side by PC measurement was 8300, the peak value on the high molecular weight side was 400,000, A _VL = 0, and A _VH = 0. The weight average particle diameter (D ₄ ) is 7.6 μm (particle diameter 12.
(Content of magnetic toner particles having a particle diameter of 7 μm or more: 3.2%, number% having a particle diameter of 3.17 μm or less: 5.0%).

Example 6 (Production Example 6 of Toner ) A styrene-n-butyl acrylate maleic anhydride copolymer having an acid value and a molecular weight distribution different from that of the resin composition (I) was used. Production example 1 using fine particles and metal oxides as A-1, B-3 and C-1, respectively
In the same manner as in the above, a toner VI shown in Table 4 was prepared. The toner of this developer has a low molecular weight side peak value of 32,000, a high molecular weight side peak value of 730,000 according to GPC measurement, A _VL = 21,
A _VH = 7, acid value / total acid value = 0.46. The weight average particle diameter (D ₄ ) is 6.3 μm (content of magnetic toner particles having a particle diameter of 12.7 μm or more: 3.2%, particle diameter 3.17 μm)
The following number%: 19.0%).

[0201]Comparative Examples 1 to 5 (Comparative Production Examples 1 to 1 of Toner)
5) Table 1 shows the inorganic fine powder, resin fine particles and metal oxide of Toner I.
Hydrophobic silica A-2,4 shown in 1 and resin fine particles shown in Table 2
Substituents B-1 and B-4 and metal oxides C-1 to C-4 shown in Table 3
In the same manner as in Production Example 1 except that
Image toners (i) to (v) were prepared.

Example 7 The toner unit I was used in a developing container of the device unit, and the device unit was mounted on a remodeled machine in which a Canon LBP309GII was remodeled from 16 sheets / min to 30 sheets / min, and image output was evaluated. . The process speed at this time is 140 mm
/ Sec.

In this embodiment, the organic photoconductor (OP)
C) As the drum, a tetrafluoroethylene-hexafluoropropylene copolymer fine powder (emulsion polymerization fine powder having an average particle diameter of 0.32 μm) was placed on the outermost layer of the organic photoconductor (OPC) layer. (OPC) Layer Photoconductor A in which 25% of the total composition was dispersed was used.

As a charging roller, as shown in FIG.
A metal core 2a, a lower layer 2b formed around the outer periphery of the metal core, and an upper layer 2 formed around the outer periphery of the lower layer 2b
c, and in this embodiment, the outer diameter is 15 mm (core 2a
The diameter was 8 mm and the thickness of the upper layer 2c was 150 μm. The hardness of the charging roller is 45 ° in ASKER-C (A
Using a SKER-C hardness tester 100, the average value was measured at a total of 9 points for each of the center and left and right at a load of 500 g.

In this embodiment, the photosensitive drum 1 has a charging roller 2 which comes into contact with a predetermined pressure.
Is rotated in the direction of the arrow with the rotation of. A voltage (V _ac + V _dc ; V _dc = −700 V, peak-to-peak voltage V _pp = 1800 V, frequency Vf = 1000 Hz) obtained by superimposing the AC voltage V _ac and the DC voltage V _dc from the power supply unit is applied to the charging roller 2. Then, the photosensitive drum 1 was uniformly charged to V _D = −700 V.

At this time, the charging noise due to the vibration between the charging roller 2 and the photosensitive drum 1 was at a level that did not cause any problem in practical use. Then charged surface of the photosensitive drum 1, by scanning a laser beam of minute spots according to an image pattern to form an electrostatic latent image of the V _L = -170V, AC bias f = 1800Hz, V _pp = The electrostatic latent image on the OPC surface was developed while applying 1400 V and a DC bias V _dc = −500 V between the toner and the developing sleeve to form a toner image.

The formed toner image is transferred by applying a positive charge from the back of the transfer paper by a transfer device in which a transfer roller having a conductive elastic layer is in contact with an OPC drum at a contact pressure of 50 g / cm. A fixed image was obtained by passing through a heating / pressing roller fixing device. At this time, the surface temperature of the heating roller of the heating and pressing roller fixing device was set to 185 ° C., the total pressure between the heating roller and the pressing roller was set to 5.5 kg, and the nip was set to 4 mm.

Under the above set conditions, low temperature and low humidity (15 ° C./1
0% RH) and high-temperature and high-humidity (32.5 ° C./80% RH) environment, the following intermittent image formation test was performed. The printing speed was 1 sheet / 12 sec.

In a low-temperature and low-humidity environment, after taking an initial sample, 100 images of 9 pieces of 5 mm square solid black (three rows and three rows) were continuously printed to obtain images for evaluation of fixability. Thereafter, the durability of 20,000 sheets was performed while successively supplying toner.

Evaluation (1) Image Density An image of 9 pieces (3 rows and 3 rows) of 5 mm square solid black was printed on ordinary plain paper for copying (75 g / m ² ), and a “Macbeth reflection densitometer” ( (Macbeth Co., Ltd.) was used to measure the relative density of the original image with respect to the printed image in the white background portion of 0.00.

(2) Fixing property Under a low-temperature and low-humidity environment, 5
100 images of 9 mm square solid black (3 rows, 3 rows)
Using the printed sample, the fixed image was rubbed with a soft thin paper under a load of 50 g / cm ² , and the worst value of the decrease in image density before and after rubbing was evaluated as follows. A (excellent): less than 5% B (good): 5% to less than 10% C (acceptable): 10% to less than 20% D (bad): 20% or more

(3) Offset Resistance The offset resistance was evaluated by printing out a sample image having an image area ratio of about 5% and determining the degree of stain on the image. A (excellent): Not generated B (Good): Very slightly generated C (OK): Slightly generated D (Bad): Dirt on the image was significantly generated

(4) Charging Sound The charging sound during printing was heard at a distance of 50 cm from the main body and evaluated. A (excellent): not at all worried B (good): hardly worried C (acceptable): slightly worried D (bad): considerably worried

(5) Image Deletion Under a high-temperature and high-humidity environment, 20,000 sheets of paper were durable while toner was successively supplied, and the image deletion was evaluated. A (excellent): not generated B (good): slightly generated C (acceptable): slightly generated D (bad): significantly generated, and the entire image blurred

(6) Fixing of Toner on Photosensitive Drum Surface After the endurance of 20,000 sheets in a high temperature and high humidity environment, visual evaluation and image evaluation of the photosensitive drum surface were performed. A (excellent): Not generated B (Good): Slightly generated, but no effect on image C (OK): Adhesion is conspicuous but has little effect on image D (Poor): Adhesion is remarkable and image is not applied Table 6 shows the evaluation results, which are greatly affected by

Examples 8 to 11 Evaluations were made in the same manner as in Example 7 except that toners II to V were used as the respective toners. Table 6 shows the results.

Example 12 Example 7 except that the charging roller was changed to one having a hardness of 59 °.
The evaluation was performed in the same manner as described above. Table 6 shows the results.

Example 13 Example 7 except that the charging roller was changed to one having a hardness of 62 °.
The evaluation was performed in the same manner as described above. Table 6 shows the results.

Comparative Examples 6 to 9 Evaluations were made in the same manner as in Example 7 except that (i) to (iv) were used as the respective toners. Table 6 shows the results.

Comparative Example 10 Evaluation was performed in the same manner as in Example 7 except that the photosensitive drum B was prepared by removing the fluorine resin fine particles of the photosensitive drum A and the toner (v) was used. Table 6 shows the results.

Comparative Example 11 Comparative Example 1 except that the charging roller was changed to one having a hardness of 70 °.
Evaluation was performed in the same manner as in the case of 0. Table 6 shows the results.

[0222]

[Table 1]

[0223]

[Table 2]

[0224]

[Table 3]

[0225]

[Table 4]

[0226]

[Table 5]

[0227]

[Table 6]

[0228]

According to the present invention, the toner for developing an electrostatic image having a defined particle size distribution contains an inorganic fine powder having a defined particle size, and a metal oxide and resin fine particles having a defined average particle size and shape coefficient. This stabilizes the chargeability of the toner, balances the abrasion of the photoreceptor by the toner, prevents toner and other substances from sticking to the photoreceptor, prevents uneven shaving of the photoreceptor, and is used for speeding up the device. However, a high-quality image can be obtained over a long period of time.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an example of an image forming apparatus suitable for the present invention.

FIG. 2 is a schematic view showing a transfer unit suitable for the present invention.

FIG. 3 is a schematic view showing a charging unit suitable for the present invention.

FIG. 4 is a schematic view of a tablet forming apparatus used for measuring a volume resistivity value of resin fine particles.

FIG. 5 is a schematic view showing an example of the device unit of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electrostatic latent image carrier (photosensitive drum) 2 charging roller 4 developing device 5 toner carrier 9 transfer roller 10 bias voltage applying means

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI G03G 5/147 504 G03G 5/147 504 9/083 9/08 301 9/087 101 15/08 507 321 15/08 507L (56 References JP-A-4-44051 (JP, A) JP-A-7-152197 (JP, A) JP-A-5-19527 (JP, A) JP-A-8-101525 (JP, A) JP-A-6-124863 (JP, A) JP-A-7-29528 (JP, A) JP-A-6-348057 (JP, A) JP-A-7-92737 (JP, A) A) JP-A-8-30029 (JP, A) JP-A-5-173366 (JP, A) JP-A-6-194873 (JP, A) JP-A-6-194864 (JP, A) JP-A-6-194864 JP-A-123994 (JP, A) JP-A-5-72801 (JP, A) JP-A-7-98519 (JP, A) Open flat 8-44148 (JP, A) JP flat 8-69148 (JP, A) (58 ) investigated the field (Int.Cl. ^7, DB name) G03G 9/08 G03G 5/147

Claims (80)

(57) [Claims] At least a toner particle, an inorganic fine powder,
An electrostatic image developing toner comprising resin fine particles and metal oxide particles, wherein the electrostatic image developing toner has a weight average particle diameter of 4 to 12 μm.
The number% of 3.17 μm or less is 30 number% or less, the primary particles of the inorganic fine powder have an average particle diameter of 1 to 50 nm, and the resin fine particles have an average particle diameter of 0.1 to 2 μm. Wherein the metal oxide has an average particle size of 0.3 to 3 μm and a shape factor SF1 of 150 to 250. Image developing toner. 2. The resin fine particles have a shape factor SF1 of 115.
Or more and less than 145, and the metal oxide has a shape factor S
2. The electrostatic image developing toner according to claim 1, wherein F1 is 160 to 230. 3. The resin fine particles have a shape factor SF2 of 110.
The metal oxide has a shape factor S
The electrostatic image developing toner according to claim 1, wherein F2 is 160 to 300. 4. 4. The resin fine particles have a shape factor SF2 of 120.
Or more and less than 175, and the metal oxide has a shape factor S
4. The toner according to claim 1, wherein F2 is 175 to 270. 5. The inorganic fine powder is charged to the same polarity as the toner particles, the resin fine particles are charged to the same polarity as the toner particles, and the resin fine particles have a volume resistivity of 10 ⁷ to 10 ¹⁴ Ωcm.
5. The electrostatic image developing toner according to claim 1, wherein the metal oxide is charged to a polarity opposite to that of the toner particles. 6. The amount of the inorganic fine powder added to the toner particles 10
0.3 to 3.0 parts by weight with respect to 0 parts by weight; the addition amount of the resin fine particles is 0.005 to 0.5 parts by weight with respect to 100 parts by weight of the toner particles; The toner for developing an electrostatic image according to any one of claims 1 to 5, wherein the amount of the toner is 0.05 to 5.0 parts by weight based on 100 parts by weight of the toner particles. 7. The inorganic fine powder has a specific surface area of 70 to 300.
m ² / g, and the specific surface area of the resin fine particles is 5.0 to 2
0.0 m ² / g, and the specific surface area of the metal oxide is 0.1 m ² / g.
2. The composition according to claim 1, wherein the amount is 5 to 10.0 m ² / g.
7. The electrostatic image developing toner according to any one of items 1 to 6. 8. The toner for developing an electrostatic image according to claim 1, wherein said inorganic fine powder is hydrophobic silica. 9. The electrostatic image developing toner according to claim 1, wherein the inorganic fine powder is treated with silicone oil. 10. The method according to claim 1, wherein the resin fine particles are styrene or acrylic organic fine particles.
10. The toner for developing an electrostatic image according to any one of items 1 to 9. 11. The toner for developing an electrostatic image according to claim 1, wherein the metal oxide is strontium titanate and / or cerium oxide. 12. The polymer component of the toner particles comprises: (a) substantially free of a THF-insoluble component; and (b) a THF-soluble component of the polymer component has a molecular weight of at least 3 × 10 3 in a GPC chromatogram. ^{3 to} 3 × 10 ⁴
And a molecular weight of 1 × 10 ⁵ to
The electrostatic image developing toner according to any one of claims 1 to 11, wherein the toner has a subpeak or a shoulder in an area of 3 x 10 < ⁶ >, and (c) has an acid value of 1 mgKOH / g or more. 13. The polymer component of the toner particles is a low molecular weight polymer (molecular weight of 5 × 10
Less than ⁴ area) acid value of (A _VL) and high molecular weight polymer (GP
The acid value (A _VH ) of a C chromatogram having a molecular weight of 5 × 10 ⁴ or more satisfies the following condition: A _VL > A _VH . An electrostatic image developing toner. 14. The low molecular weight polymer of the polymer component has an acid value (A _VL ) of 21 to 35 mg KOH / g, and the high molecular weight polymer has an acid value (A _VH ) of 0.5 to 11 mg KOH.
The toner for developing an electrostatic charge image according to any one of claims 1 to 13, wherein the relationship of the difference is 10 ≦ (A _VL −A _VH ) ≦ 27. 15. The electrostatic image developing toner according to claim 1, wherein the polymer component has an acid value / total acid value of 0.7 or less. 16. The polymer component is a THF-soluble GPC.
In the chromatogram, the molecular weight is 3 × 10 ⁴ or more and 1 × 1
0 to less than ⁵ regions toner according to any one of claims 1 to 15, characterized in that it has a minimum value. 17. The electrostatic image developing toner according to claim 1, wherein the toner particles contain a magnetic material. 18. The toner for developing an electrostatic image according to claim 1, wherein the toner contains a magnetic material containing silicon. 19. An electrostatic image holding member and a developing device for developing an electrostatic image formed on the electrostatic image holding member using an electrostatic image developing toner in an apparatus unit detachable from the image forming apparatus main body. Means, the toner for developing an electrostatic image is at least a toner particle,
It contains inorganic fine powder, resin fine particles and metal oxide particles, and the toner for developing an electrostatic image has a weight average particle diameter of 4 to 12 μm.
The number% of 3.17 μm or less is 30 number% or less, the primary particles of the inorganic fine powder have an average particle diameter of 1 to 50 nm, and the resin fine particles have an average particle diameter of 0.1 to 2 μm. Wherein the shape factor SF1 is 100 or more and less than 150, the metal oxide has an average particle size of 0.3 to 3 μm, and the shape factor SF1 is 150 to 250. . 20. The electrostatic image holding member is a photosensitive drum,
2. A photosensitive drum is provided with contact charging means.
10. The device unit according to 9. 21. The apparatus unit according to claim 20, wherein the contact charging means is a charging roller. 22. The apparatus unit according to claim 19, wherein a cleaning unit is mounted on the electrostatic image holding member. 23. The apparatus unit according to claim 22, wherein the cleaning means is a blade cleaning means. 24. The resin fine particles have a shape factor SF1 of 11
24. The apparatus unit according to claim 19, wherein the metal oxide has a shape factor SF1 of 160 to 230, and the metal oxide has a shape factor SF1 of 160 to 230. 25. The resin fine particles have a shape factor SF2 of 11
The device unit according to any one of claims 19 to 24, wherein the metal oxide has a shape factor SF2 of 160 to 300, from 0 to less than 200. 26. The resin fine particles having a shape factor SF2 of 12
0 or more and less than 175, and the metal oxide has a shape factor SF
2. The method according to claim 1, wherein 2 is 175 to 270.
26. The device unit according to any one of 9 to 25. 27. The inorganic fine powder is charged to the same polarity as toner particles, the resin fine particles are charged to the same polarity as toner particles,
And the volume resistivity of the fine resin particles is 10 ⁷ to 10 ¹⁴ Ωc.
27. The apparatus unit according to claim 19, wherein the metal oxide is charged to a polarity opposite to that of the toner particles. 28. The amount of the inorganic fine powder added to the toner particles 1
0.3 to 3.0 parts by weight with respect to 100 parts by weight, and the addition amount of the fine resin particles is 0.005 to 0.5 parts by weight with respect to 100 parts by weight of the toner particles. 28. The apparatus unit according to claim 19, wherein the amount is 0.05 to 5.0 parts by weight based on 100 parts by weight of the toner particles. 29. The inorganic fine powder has a specific surface area of 70 to 30.
0 m ² / g, and the specific surface area of the resin fine particles is 5.0 to 5.0 m ² / g.
20.0m was ² / g, apparatus unit according to any of claims 19 to 28 the specific surface area of the metal oxide is characterized by a 0.5~10.0m ² / g. 30. The apparatus unit according to claim 19, wherein said inorganic fine powder is hydrophobic silica. 31. The method according to claim 19, wherein the inorganic fine powder is treated with silicone oil.
The device unit according to any one of the above. 32. The resin fine particles are styrene-based or acrylic-based organic fine particles.
32. The device unit according to any one of 9 to 31. 33. The apparatus unit according to claim 19, wherein said metal oxide is strontium titanate or cerium oxide. 34. The polymer component of the toner particles comprises: (a) substantially free of a THF-insoluble component, and (b) a THF-soluble component of the polymer component is at least 3 × 10 3 in a GPC chromatogram. ^{3 to} 3 × 10 ⁴
And a molecular weight of 1 × 10 ⁵ to
The apparatus unit according to any one of claims 19 to 33, having a subpeak or a shoulder in a region of 3 x 10 < ⁶ >, and (c) having an acid value of 1 mgKOH / g or more. 35. A low molecular weight polymer (the molecular weight of which is 5 × 10 5 in a GPC chromatogram) of a polymer component of the toner particles.
Less than ⁴ area) acid value of (A _VL) and high molecular weight polymer (GP
_{35. The method according} to claim 19, wherein an acid value (A _VH ) of a C chromatogram having a molecular weight of 5 × 10 ⁴ or more satisfies the following condition: A _VL > A _VH . Equipment unit. 36. The low molecular weight polymer of the polymer component has an acid value (A _VL ) of 21 to 35 mg KOH / g, and the high molecular weight polymer has an acid value (A _VH ) of 0.5 to 11 mg KOH / g.
The apparatus unit according to any one of claims 19 to 35, wherein g is 10 and (A _VL -A _VH ) ≤ 27. 37. The polymer component according to claim 19, wherein the value of (acid value / total acid value) is 0.7 or less.
The device unit according to any one of the above. 38. GPC of the THF-soluble component of the polymer component
In the chromatogram, the molecular weight is 3 × 10 ⁴ or more and 1 × 1
The device unit according to any one of claims 19 to 37, wherein the device unit has a minimum value in a region less than 0 ⁵ . 39. The apparatus unit according to claim 19, wherein said toner particles contain a magnetic substance. 40. The apparatus unit according to claim 19, wherein the toner contains a magnetic material containing silicon. 41. a step of charging the surface of the electrostatic image holder,
Forming an electrostatic image on the electrostatic image holding member, developing the electrostatic image with a toner for developing an electrostatic image to form a toner image, and transferring the toner image formed on the electrostatic image holding member to a transfer material And a step of cleaning the surface of the electrostatic image holding member by contacting the surface of the electrostatic image holding member with the cleaning means after the transfer, and repeating the above-described steps using the cleaned electrostatic image holding member. The toner for developing an electrostatic image is at least a toner particle,
It contains inorganic fine powder, resin fine particles and metal oxide particles, and the toner for developing an electrostatic image has a weight average particle diameter of 4 to 12 μm.
The number% of 3.17 μm or less is 30 number% or less, the primary particles of the inorganic fine powder have an average particle diameter of 1 to 50 nm, and the resin fine particles have an average particle diameter of 0.1 to 2 μm. Wherein the metal oxide has an average particle diameter of 0.3 to 3 μm and a shape factor SF1 of 150 to 250. Method. 42. The image forming method according to claim 41, wherein the electrostatic image holder is charged by a contact charging unit to which a bias is applied. 43. The image forming method according to claim 42, wherein the electrostatic image holder is a photosensitive drum, and the contact charging means is a charging roller. 44. The electrostatic latent image carrier has a laminated structure having at least a conductive support and a charge generation layer,
The image forming method according to any one of claims 39 to 43, wherein the surface layer of the electrostatic latent image carrier has a fluorine atom, a silicon atom, or both. 45. The resin fine particles have a shape factor SF1 of 11
45. The image forming method according to claim 39, wherein the shape factor SF1 of the metal oxide is 5 or more and less than 145, and the metal oxide has a shape factor SF1 of 160 to 230. 46. The resin fine particles have a shape factor SF2 of 11
0 or more and less than 200, and the shape factor SF of the metal oxide
2. The number 2 is between 160 and 300.
45. The image forming method according to any one of 9 to 44. 47. The resin fine particles have a shape factor SF2 of 12
47. The image forming method according to claim 39, wherein the metal oxide has a shape factor SF2 of 175 to 270 from 0 to less than 175. 48. The inorganic fine powder is charged to the same polarity as toner particles, the resin fine particles are charged to the same polarity as toner particles,
And the volume resistivity of the fine resin particles is 10 ⁷ to 10 ¹⁴ Ωc.
The image forming method according to any one of claims 39 to 47, wherein m and the metal oxide are charged to a polarity opposite to that of the toner particles. 49. The amount of the inorganic fine powder added to toner particles 1
0.3 to 3.0 parts by weight with respect to 100 parts by weight, and the addition amount of the fine resin particles is 0.005 to 0.5 parts by weight with respect to 100 parts by weight of the toner particles. The image forming method according to any one of claims 39 to 48, wherein the amount is 0.05 to 5.0 parts by weight based on 100 parts by weight of the toner particles. 50. The inorganic fine powder has a specific surface area of 70 to 30.
0 m ² / g, and the specific surface area of the resin fine particles is 5.0 to 5.0 m ² / g.
20.0m was ² / g, the image forming method according to any of claims 39 to 49 the specific surface area of the metal oxide is characterized by a 0.5~10.0m ² / g. 51. The image forming method according to claim 39, wherein said inorganic fine powder is hydrophobic silica. 52. The method according to claim 39, wherein the inorganic fine powder is treated with silicone oil.
The image forming method according to any one of the above. 53. The method according to claim 3, wherein the resin fine particles are styrene-based or acrylic organic fine particles.
53. The image forming method according to any one of 9 to 52. 54. The image forming method according to claim 39, wherein said metal oxide is strontium titanate or cerium oxide. 55. The polymer component of the toner particles comprises: (a) substantially free of a THF-insoluble component; and (b) a THF-soluble component of the polymer component is at least 3 × 10 3 in a GPC chromatogram. ^{3 to} 3 × 10 ⁴
And a molecular weight of 1 × 10 ⁵ to
55. The image forming method according to claim 39, wherein the image forming method has a sub-peak or a shoulder in a region of 3 × 10 ⁶ , and (c) has an acid value of 1 mgKOH / g or more. 56. A low molecular weight polymer (the molecular weight of which is 5 × 10 5 in a GPC chromatogram) of a polymer component of the toner particles.
Less than ⁴ area) acid value of (A _VL) and high molecular weight polymer (GP
The acid value (A _VH ) of a C chromatogram having a molecular weight of 5 × 10 ⁴ or more satisfies the following condition: A _VL > A _VH . Image forming method. 57. The low molecular weight polymer of the polymer component has an acid value (A _VL ) of 21 to 35 mg KOH / g, and the high molecular weight polymer has an acid value (A _VH ) of 0.5 to 11 mg KOH / g.
57. The image forming method according to claim 39, wherein g is 10 and (A _VL -A _VH ) ≤27. 58. The polymer component according to claim 39, wherein the value of acid value / total acid value is 0.7 or less.
The image forming method according to any one of the above. 59. GPC of the THF-soluble portion of the polymer component
In the chromatogram, the molecular weight is 3 × 10 ⁴ or more and 1 × 1
The image forming method according to any one of claims 39 to 58, wherein a region having a value less than 0 ⁵ has a minimum value. 60. The image forming method according to claim 39, wherein the toner particles contain a magnetic material. 61. The image forming method according to claim 39, wherein the toner contains a magnetic material containing silicon. 62. A step of applying a voltage having at least an AC component to a charging member, and charging the surface of the electrostatic image holder by bringing the charging member into contact with the electrostatic image holder; Forming an electrostatic charge image, and developing the electrostatic charge image with toner, wherein the charging member comprises an upper layer portion made of a high-resistance element in contact with the electrostatic image carrier, and a lower layer portion of the upper layer portion. Comprising a conductive lower layer portion to which a voltage having at least an AC component is applied, wherein the electrostatic image holder has a laminated structure having at least a conductive support and a charge generation layer, The surface layer of the electrostatic image holder has fluorine atoms, silicon atoms or both, and the toner has at least toner particles, inorganic fine powder, resin fine particles and metal oxide particles, and the toner has a weight average Particle size is 4 to 12 μm, 3.1
The number% of 7 μm or less is 30 number% or less, the primary particles of the inorganic fine powder have an average particle size of 1 to 50 nm, and the resin fine particles have an average particle size of 0.1 to 2 μm. An image forming method, wherein the coefficient SF1 is 100 or more and less than 150, the metal oxide has an average particle diameter of 0.3 to 3 μm, and the shape factor SF1 is 150 to 250. 63. The charging member has an ASKER-C hardness.
The image forming method according to claim 62, wherein the angle is 60 ° or less. 64. The resin fine particles have a shape factor SF1 of 11
64. The image forming method according to claim 62, wherein the metal oxide has a shape factor SF1 of 160 to 230, from 5 to less than 145. 65. The resin fine particles have a shape factor SF2 of 11
65. The image forming method according to claim 62, wherein the shape factor SF2 of the metal oxide is from 0 to less than 200 and the shape factor SF2 of the metal oxide is from 160 to 300. 66. The resin fine particles have a shape factor SF2 of 12
0 or more and less than 175, and the metal oxide has a shape factor SF
7. The method according to claim 6, wherein 2 is 175 to 270.
The image forming method according to any one of Items 2 to 65. 67. The inorganic fine powder is charged to the same polarity as toner particles, the resin fine particles are charged to the same polarity as toner particles,
And the volume resistivity of the fine resin particles is 10 ⁷ to 10 ¹⁴ Ωc.
67. The image forming method according to any one of claims 62 to 66, wherein m and the metal oxide is charged to a polarity opposite to that of the toner particles. 68. The amount of the inorganic fine powder added to the toner particles 1
0.3 to 3.0 parts by weight with respect to 100 parts by weight, and the addition amount of the fine resin particles is 0.005 to 0.5 parts by weight with respect to 100 parts by weight of the toner particles. The image forming method according to any one of claims 62 to 67, wherein the amount is 0.05 to 5.0 parts by weight based on 100 parts by weight of the toner particles. 69. The inorganic fine powder has a specific surface area of 70 to 30.
0 m ² / g, and the specific surface area of the resin fine particles is 5.0 to 5.0 m ² / g.
20.0m was ² / g, the image forming method according to any of claims 62 to 68 the specific surface area of the metal oxide is characterized by a 0.5~10.0m ² / g. 70. The image forming method according to claim 62, wherein said inorganic fine powder is hydrophobic silica. 71. The inorganic fine powder has been treated with silicone oil.
The image forming method according to any one of the above. 72. The resin fine particles are styrene or acrylic organic fine particles.
72. The image forming method according to any one of items 2 to 71. 73. The image forming method according to claim 62, wherein the metal oxide is strontium titanate or cerium oxide. 74. The polymer component of the toner particles is (a) substantially free of a THF-insoluble component, and (b) the THF-soluble component of the polymer component is at least a molecular weight of 3 × 10 3 in a GPC chromatogram. ^{3 to} 3 × 10 ⁴
And a molecular weight of 1 × 10 ⁵ to
74. The image forming method according to claim 62, wherein the image forming method has a sub-peak or a shoulder in a region of 3 × 10 ⁶ , and (c) has an acid value of 1 mgKOH / g or more. 75. A low molecular weight polymer (polymer having a molecular weight of 5 × 10 5 in a GPC chromatogram) of a polymer component of the toner particles.
Less than ⁴ area) acid value of (A _VL) and high molecular weight polymer (GP
75. The acid value (A _VH ) of a C chromatogram having a molecular weight of 5 × 10 ⁴ or more) satisfies the following condition: A _VL > A _VH . Image forming method. 76. The acid value (A _VL ) of the low molecular weight polymer of the polymer component is 21 to 35 mg KOH / g, and the acid value (A _VH ) of the high molecular weight polymer is 0.5 to 11 mg KOH / g.
The image forming method according to any one of claims 62 to 75, wherein g is a relation of 10 ≦ (A _VL −A _VH ) ≦ 27. 77. The polymer component according to claim 62, wherein the value of acid value / total acid value is 0.7 or less.
The image forming method according to any one of the above. 78. GPC of a THF-soluble component of the polymer component
In the chromatogram, the molecular weight is 3 × 10 ⁴ or more and 1 × 1
The image forming method according to any one of claims 62 to 77, wherein a region having a value less than 0 ⁵ has a local minimum value. 79. The image forming method according to claim 62, wherein the toner particles contain a magnetic material. 80. The image forming method according to claim 62, wherein the toner contains a magnetic material containing silicon.