JP3168380B2 - Electrostatic image developing toner, toner manufacturing method and image forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electrophotography, electrostatic printing,
In an image forming method such as magnetic recording, the present invention relates to a toner for visualizing an electrostatic latent image, a method for producing the toner including a melt-kneading step, and an image forming method using the toner.
In particular, the present invention relates to a toner for developing an electrostatic image, which is used in a fixing method of heating and fixing a visible image formed by a toner to a recording material, a method for manufacturing the toner including a melt-kneading process, and an image forming method using the toner. .

[0002]

2. Description of the Related Art An electrophotographic method is disclosed in U.S. Pat.
A number of 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, but generally, a photoconductive substance is used. An electric latent image is formed on the photoreceptor by various means, then the latent image is developed using toner, and if necessary, a toner image is transferred to a transfer material such as paper. The toner is fixed by pressurization or solvent vapor to obtain a copy, and the remaining toner not transferred onto the photoreceptor is cleaned by various methods, and the above-described steps are repeated.

In recent years, such copying apparatuses have been strictly pursued for smaller size, lighter weight, higher speed, and higher reliability, and as a result, the performance required for toner has also become higher. ing. For example, various methods and apparatuses have been developed for the process of fixing a toner image on a sheet such as paper, but the most common method at present is a heat compression method using a heat roller. The heat compression bonding method using a heat roller performs fixing by allowing the toner image surface of a sheet to be fixed to pass through the surface of a heat roller having a surface formed of a material having releasability with respect to toner while contacting the surface under pressure. . In this method, since the surface of the heat roller and the toner image of the sheet to be fixed come into contact with each other under pressure, the heat efficiency when fixing the toner image on the sheet to be fixed is extremely good, and the fixing can be performed quickly. It is very effective in high-speed electrophotographic copying machines.

However, in the above-described heat roller fixing which has been frequently used, (1) there is a so-called wait time during which the image forming operation is prohibited until the heat roller reaches a predetermined temperature.

(2) The optimum temperature of the heating roller is set in order to prevent defective fixing due to the fluctuation of the temperature of the heating roller due to the passage of the recording material or other external factors and the transfer of toner to the heating roller, ie, the so-called offset phenomenon. In order to achieve this, the heat capacity of the heating roller or the heating element must be increased, which requires a large amount of electric power and causes a rise in the temperature inside the image forming apparatus.

(3) Since the pressure roller has a lower temperature than the fixing roller, when the recording material is discharged through the heating roller, the recording material and the toner on the recording material are cooled slowly. The toner becomes highly sticky, and in combination with the curvature of the roller, a paper jam may occur due to offset or entanglement of the recording material. Etc. are not fundamentally solved.

JP-A-63-313182 by the present applicant
In Japanese Patent Application Laid-Open Publication No. H10-209, an image with a short wait time and a low power consumption is fixed by a fixing device that heats a toner visible image through a heat-resistant sheet moved by a low-heat-capacity heating element heated in a pulse shape and fixes the recording material. A forming device has been proposed. Similarly, Japanese Patent Application Laid-Open No. Hei.
No. 7582 discloses a fixing device for heating and fixing a visible image of a toner to a recording material via a heat-resistant sheet.
A fixing device has been proposed in which the heat-resistant sheet has a heat-resistant layer and a release layer or a low-resistance layer to effectively prevent the offset phenomenon.

However, in order to realize a fixing method that has a short wait time and low power consumption while achieving excellent fixability of a toner-visible image to a recording material, prevention of offset, and the like, a fixing device as described above is used. In addition, the characteristics of the toner are greatly affected.

Conventionally, a method using a toner having two peaks in the molecular weight distribution as a binder resin of the toner, and a low molecular weight wax are typified by the idea of giving the toner itself good fixability and offset resistance. A method of adding a low molecular weight polyolefin polymer to a toner has been proposed.

The method described in, for example, JP-A-56-1
6144, JP-A-2-23569, JP-A-63-127254, JP-A-3-26831, JP-A-62-9356, JP-A-3-725
Japanese Patent Application Laid-Open No. 52-3304 and Japanese Patent Application Laid-Open No. 52-330
No. 5, JP-A-57-52574, JP-A-58-58574
JP-A-215659, JP-A-60-217366, JP-A-60-252361, JP-A-60-2
No. 52362, JP-A-4-97162 and the like are disclosed.

However, simply using a binder resin having two peaks in the molecular weight distribution or including a certain release agent in the toner does not improve the fixing property and the offset resistance to some extent. Although it can be seen, not only does the binder component in the toner cause non-uniformity, but also hinders the dispersion of other components such as wax, and uneven distribution and release of specific components are likely to occur. This may cause fusion to a photosensitive member or filming.

In a binder resin having two peaks, the use of a polyfunctional initiator to increase the molecular weight on the high molecular weight side is also described in JP-A-2-272559 and JP-A-3-72505. Although described, it is necessary to broaden the molecular weight distribution of the binder resin in order to apply it to the fixing property at lower temperature and the anti-offset property at higher temperature, and this is applied to the binder resin having two peaks. In such a case, the compatibility between the low-molecular component and the high-molecular component is further deteriorated due to the further polarization of the low-molecular component and the high-molecular component, so that the above-described serious problem is likely to occur.

Therefore, for example, the compatibility of the toner constituent components,
In order to improve the dispersibility, when the kneading conditions at the time of melt kneading during the production of the toner is strengthened, the molecular weight of the toner at the time of toner decreases due to the breaking of the molecular chain of the binder resin in the toner due to kneading, There are problems such as deterioration of the offset resistance, particularly the hot offset on the high temperature side.
Also, when a large amount of wax is added in order to exert a sufficient effect on the offset resistance, the blocking resistance is deteriorated, and the dispersion of the wax is further deteriorated. This promotes contamination of the surface, deteriorates the image, and poses a practical problem.

On the other hand, JP-A-4-97162 proposes a toner in which a specific aliphatic alcohol is contained in a binder resin having two peaks. However, while the conventional toner exhibits relatively good low-temperature fixability due to the plasticizing effect of the aliphatic alcohol, the amount of offset toner to the fixing roller sharply increases. It is essential to have a toner wiping device. Further, when the toner is used at a high temperature or used or stored at room temperature for a long period of time, the aliphatic alcohol grows into a large spherulite in the toner particles or blooms. This causes a serious problem such as toner fogging of the image forming section. In particular, when applied to a magnetic toner that requires uniform dispersion of high-specific-gravity magnetic fine particles, the above-described problems become apparent, and further fine-tuning of the toner particle size is attempted for the purpose of high-quality development. This causes new problems such as fusion of toner to the surface of the photosensitive drum and poor cleaning, and causes difficulty in combination with other image forming means.

The various properties required for the above-mentioned toners are often reciprocal to each other, and it is more and more desirable in recent years to satisfy both of them with high performance. Research has been conducted on comprehensive responses that include, but there is still not enough.

[0016]

SUMMARY OF THE INVENTION An object of the present invention is to significantly improve the disadvantages of the prior art, improve the fixability and the anti-offset property, and stably realize a high-quality image for a long period of time. A toner for developing an electrostatic image capable of being highly applied to an electrophotographic process which does not adversely affect a photoreceptor or a developer carrier, a method for producing the toner including a melt-kneading step, and an image using the toner The present invention provides a forming method.

[0017]

According to the present invention, there is provided a toner formed from a composition in which at least a binder resin, a colorant and a wax component are dispersed, wherein (a) the volatile component in the toner is 0.1%; Less than 1% by weight; (b) the wax component is i) having a maximum endothermic peak in the range of 70 to 130 ° C. in a DSC curve measured by a differential scanning calorimeter when the temperature is increased; ii) the maximum endothermic peak Has a maximum exothermic peak at the time of temperature fall within a range of ± 9 ° C. with respect to the peak temperature of iii), iii) the following general formula RY wherein R represents a hydrocarbon group, Y represents a hydroxyl group, It represents a carboxy group, alkyl ether group, ester group or sulfonyl group. A compound having a weight average molecular weight of 3,000 or less by GPC of 60% by weight or more.

Further, the present invention relates to a method for producing the toner.

Further, the present invention relates to an image forming method using the toner.

As a result of intensive studies, the present inventors have adjusted the content of volatile components in the toner composition and specified the physical properties of each component constituting the toner composition, thereby obtaining an extremely wide range. The present inventors have found that a stable and good toner image having a fixable temperature region, excellent in dot reproduction, and free from fog can be formed over a long period of time, and the present invention has been completed.

The toner according to the present invention is controlled so that the volatile component in the toner is less than 0.1% by weight in combination with a specific wax described later. Preferably it is less than 0.05% by weight. More preferably 0.02
% By weight.

In the present invention, the volatile component refers to a solvent or an unreacted monomer used in the production of a binder resin composition described later, as well as a low molecular weight by-product derived from the unreacted monomer, for example, oxidative decomposition of styrene. It contains benzaldehyde and benzoic acid, as well as low molecular weight components remaining in other toner constituent materials and low molecular weight components generated during toner production. Among these, the solvent used in the production of the resin and the residual component of the unreacted monomer particularly increase the plastic effect when coexisting with the wax component according to the present invention described later. Therefore, not only the wax component but also other toner composition components are dispersed. While the speed is increased, the recrystallization growth and phase separation of the wax component are also facilitated. Therefore, in the production of toner, by controlling the amount of residual solvent and unreacted monomer before and after dispersion of the wax component, it is possible to achieve a good dispersion state of the components of the toner composition and a long-term stabilization in that state. And various characteristics of the toner are remarkably improved.

That is, the residual solvent amount of the volatile component in the binder resin composition before dispersion of the wax component is 300 to
3,000 ppm and 50 to 3 in terms of unreacted monomer
00 ppm, the residual solvent amount after dispersing the wax component by hot melt kneading or the like is 1,000 ppm or less, and
The amount of the unreacted monomer is controlled within a range of 150 ppm or less.

In the present invention, the method of quantifying volatile components in the toner includes a method using thermogravimetry (TG), which is measured as a weight loss upon heating using a thermobalance or the like.
A known method such as a method using gas chromatography (GC) can be applied. GC among these
Is a particularly effective method when fixing the residual components of the solvent and unreacted monomer used in the production of the binder resin for the toner.

In the present invention, the volatile component in the toner is T
In the case of quantification by G, it can be determined from the loss on heating observed when the sample is heated to 200 ° C. Specific examples are described below.

<Measurement conditions of TG> Apparatus: TGA-7, PE7700 (manufactured by PerkinElmer) Temperature rising rate: 10 ° C./min Measurement environment: under N ₂ atmosphere

A specific example in which the solvent used in the production of the resin in the toner composition and the binder resin and the residual components of the unreacted monomer and the like are determined using GC is described below.

<GC measurement conditions> Apparatus: GC-14A (manufactured by Shimadzu Corporation) Column: fused silica capillary column (manufactured by J & W SCIENTIFFC) (size: 30 m × 0.249 mm, liquid phase: DBWAX, film thickness: 0) .25 μm) Sample: Using 2.55 mg of DMF as an internal standard, add 100 ml of acetone to make a solvent containing an internal standard. Next, 400 mg of the developer is made into a 10 ml solution with the above solvent. Place on an ultrasonic shaker for 30 minutes and leave for 1 hour. Next, the mixture is filtered with a 0.5 μm filter. The amount of sample to be implanted is 4 μl.

Detector: FID (split ratio: 1:20) Carrier gas: N ₂ gas Oven temperature: 70 ° C. → 220 ° C. (After waiting at 70 ° C. for 2 minutes, the temperature is raised at a rate of 5 ° C./min.) Temperature: 200 ° C Detector temperature: 200 ° C Calibration curve preparation: DMF similar to the sample solution, gas chromatographic measurement of the standard sample obtained by adding the target monomer to the acetone solution, and the weight of the monomer and the internal standard DMF Find the ratio / area ratio.

The wax component according to the present invention shows a DSC curve measured by a differential scanning calorimeter of 7% when the temperature is raised.
It is characterized by having a maximum endothermic peak in the range of 0 to 130 ° C. and having a maximum exothermic peak at the time of temperature fall in a range of ± 9 ° C. with respect to the peak temperature of the maximum endothermic peak.

In the DSC curve at the time of temperature rise, the wax component melts in the above-mentioned temperature range, and at the time of toner production, coexists with the volatile component, thereby exerting an appropriate plasticizing effect on the binder resin to obtain a uniform toner composition. Give things. In addition, after the toner is manufactured, the releasing effect of the wax component dispersed uniformly, in addition to the good fixing property, is effectively exhibited, so that a fixing area is secured, and further, the developing characteristics of the toner are improved.

On the other hand, in the DSC curve at the time of temperature decrease, an exothermic peak accompanying the coagulation and crystallization of the wax component is observed.
The presence of this exothermic peak in a temperature region close to the endothermic peak at the time of temperature increase indicates that the wax component is more homogeneous, and by reducing this difference, the thermal responsiveness of the wax component is reduced. At the same time, it is possible to suppress the excessive plasticizing effect at the same time. Therefore, the wax component according to the present invention, when the toner composition containing the wax component is heated by a fixing device, instantly plasticizes a binder resin described below, and greatly contributes to low-temperature fixing, while significantly contributing to low-temperature fixing. The synergistic effect with the resin can also effectively exert the releasability, and it is possible to achieve both low-temperature fixing property and high-temperature offset resistance at a high level. Further, the dispersion of the wax in a homogeneous state does not adversely affect the triboelectric charging, thereby further improving the developing characteristics of the toner. However, such a wax component has a high recrystallization speed and is liable to cause phase separation. Therefore, dispersion of the wax component, deterioration of the toner due to an external force received from the image forming apparatus, and blooming of the wax component due to long-term storage are caused. As described above, the problem was caused by precisely controlling the amount of the volatile component remaining in the toner composition, and the volatile component contained in the toner component before the wax component was dispersed. By controlling the amount, the dispersion state of each toner component was remarkably improved, and various characteristics of the toner were remarkably improved.

The wax used in the present invention is obtained from the following wax. Paraffin wax and its derivatives, montan wax and its derivatives,
Examples thereof include microcrystal wax and its derivatives, Fischer-Tropsch wax and its derivatives, polyolefin wax and its derivatives, and derivatives include oxides, block copolymers with vinyl monomers, and graft-modified products.

As other waxes, alcohols and derivatives thereof, fatty acids and derivatives thereof, acid amides, esters, ketones, hydrogenated castor oil and derivatives thereof, vegetable waxes, animal waxes, mineral waxes, and petrolactam can also be used. The derivatives include saponified compounds, salts, alkylene oxide adducts, and esters.

Among the waxes, preferably used are low-molecular-weight polyalkylenes obtained by radical polymerization of alkylene under high pressure or polymerization using a Ziegler catalyst and by-products at this time; high-molecular-weight polyalkylenes are obtained by thermal decomposition. A wax obtained from a low molecular weight polyalkylene; a distillation residue of a hydrocarbon obtained by using a catalyst from a synthesis gas composed of carbon monoxide and hydrogen, or a synthetic hydrocarbon obtained by hydrogenating these; An antioxidant may be added. Alternatively, it is a linear alcohol, alcohol derivative, fatty acid, acid amide, ester or montan derivative. Further, it is also preferable that fatty acid impurities have been removed in advance.

Particularly preferred are those obtained by polymerizing an alkylene such as ethylene with a Ziegler catalyst, and by-products at this time, such as Fischer-Tropsch wax having a hydrocarbon having a number of carbon atoms of several thousand, especially up to about 1,000. Is good.

From these waxes, the waxes were fractionated by molecular weight using a press sweating method, a solvent method, vacuum distillation, supercritical gas extraction, fractional crystallization (for example, liquid crystal precipitation and crystal filtration). Waxes are also preferably used in the present invention. After fractionation, oxidation, block copolymerization, or graft modification may be performed. For example, those obtained by removing low-molecular-weight components, those obtained by extracting low-molecular-weight components,
Further, those having an arbitrary molecular weight distribution such as those obtained by removing low molecular weight components from these.

In particular, adding a low molecular weight wax component to the toner according to the present invention is one of the preferred embodiments of the present invention. These low molecular weight wax components have a weight average molecular weight (Mw) of 30,000 or less, preferably 10,000 or less. More preferably, Mw is 400 to 3,000.
0, the number average molecular weight (Mn) is desirably 200 to 2,000, and Mw / Mn is desirably 3.0 or less.

By having such a molecular weight distribution, it is possible to give the toner favorable physical characteristics. In other words, when the molecular weight is smaller than the above range, the composition is susceptible to thermal or mechanical influences excessively, and causes problems in offset resistance and storage stability. Further, when the molecular weight is larger than the above range, not only the effect of adding the compound is lost, but also a problem occurs in matching with the image forming apparatus.

Further, the low molecular weight wax component used in the present invention has the following general formula: RY

[R: represents a hydrocarbon group. Y represents a hydroxyl group, a carboxyl group, an alkyl ether group, an ester group, or a sulfonyl group. Having a weight average molecular weight of 30 by gel permeation chromatography having
The object of the present invention can be achieved to a high degree by containing 60% by weight or more, preferably 70% by weight or more of a compound of not more than 00. That is, matching with a binder resin described later is very good.

Specific examples of the compound include: (A) CH ₃ (CH ₂ ) _n CH ₂ OH (n = about 20 to about 20)
_{0) (B) CH 3 (} CH 2) n CH 2 COOH (n = about 20 to about _{200) (C) CH 3 (} CH 2) n CH 2 OCH 2 (CH 2) m CH3 (n = about 20 (D) CH ₃ (CH ₂ ) _n CH ₂ COO (CH ₂ ) _m CH ₃ (n = about 20 to about 200, m = 0 to about 100) (E) CH ₃ (CH ₂ ) _n CH ₂ OSO ₃ H (n = about 20 to
About 200). These compounds are derivatives of the compound (A), and the main chain is a linear saturated hydrocarbon. As long as the compound is derived from the compound (A), those other than those shown in the above examples can also be used.

Particularly preferred as the low molecular weight wax component are those having a carbon number of 25 or more, more preferably 35 or more, especially 45 or more in the carbon number distribution measured by gas chromatography (GC). Is preferred. The low molecular weight synthetic wax component, in which the peak appearing according to the number of carbon atoms (one methylene chain) and the intensity of the regularity appears for each carbon number, is easy to control the plastic effect,
It is preferably used in the present invention.

In order to achieve a high balance of toner characteristics such as development characteristics, fixing properties, and high-temperature offset resistance, the maximum peak should be 25 or more, especially 30 or more, and more preferably 35 to 150. Some are preferably used.

In the DSC measurement of the present invention, since the exchange of heat of the wax is measured and its behavior is observed, it is preferable from the principle of measurement that the measurement be performed with a high-precision internal heating input compensation type differential scanning calorimeter. For example, DSC-7 manufactured by PerkinElmer can be used.

The measuring method is as described in ASTM D3418-82.
Perform according to. The DSC curve used in the present invention is obtained by raising and lowering the temperature once, taking a pre-history, and then setting the temperature rate to 10 ° C./m.
In, a DSC curve measured when the temperature is raised is used.

In the present invention, the molecular weight distribution of the wax is G
It is measured by a PC under the following conditions.

<GPC Measurement Conditions for Wax> Apparatus: GPC-150C (manufactured by Waters) Column: Duplex of GMH-HT (manufactured by Tosoh Corporation) Temperature: 135 ° C. Solvent: o-dichlorobenzene (0.1% ionol added) ) Flow rate: 1.0 ml / min. Sample: 0.4 ml of 0.15% by weight sample is injected

Measurement is performed under the above conditions, and the molecular weight of the sample is calculated using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample. In addition, Mark-Hou
It is calculated by converting to polyethylene using a conversion formula derived from the wink viscosity formula.

In the present invention, the carbon number distribution of the wax is measured by gas chromatography (GC) under the following conditions.

<GC Measurement Conditions> Apparatus: HP 5890 Series II (manufactured by Yokogawa Electric Corporation) Column: SGE HT-5 6 m × 0.53 mm ID × 0.15 μm Carrier gas: He 20 ml / min Constant Flow Mode Oven temperature : 40 ° C → 450 ° C Inlet temperature: 40 ° C → 450 ° C Detector temperature: 450 ° C Detector: FID Inlet: With pressure control

Under the above conditions, the injection port was pressure-controlled, and the measurement was performed while keeping the optimum flow rate constant, and n-paraffin was used as a standard sample.

The binder resin component in the toner composition according to the present invention has a main peak in a molecular weight region of 2,000 to 30,000 and a molecular weight of less than 50,000 in a GPC molecular weight distribution measured by a THF-soluble component. Low molecular weight component and molecular weight 1
Those comprising a high molecular weight component having a molecular weight of 50,000 or more having a subpeak or a shoulder in a region of not less than 100,000 are preferred.

When the peak molecular weight of the high molecular weight component of the binder resin is less than 100,000, not only does the toner have an unsatisfactory high-temperature offset resistance, but also the wax component according to the present invention retains the dispersibility and dispersion state. Is insufficient, and image defects such as a decrease in image density are likely to occur. Further, when the peak molecular weight of the low molecular weight component of the binder resin is less than 2,000, the plasticization by the wax component becomes abrupt, so that a serious problem occurs in the hot offset resistance and the storage stability. . Further, since phase separation easily occurs locally, the frictional charging of the toner becomes non-uniform, and the developing characteristics deteriorate.
On the other hand, when the peak molecular weight exceeds 30,000, the dispersion state of the wax component is improved to some extent, and although the developing characteristics are improved, the fixability is not sufficient. Further, when the toner is manufactured by a pulverization method or the like, the productivity is reduced.

That is, by specifying the molecular weight distribution of GPC of the binder resin component as described above, it is possible to easily balance various properties required for the toner.

The binder resin component in the toner composition according to the present invention does not substantially contain a THF-insoluble component, and has a molecular weight of 1,000 or less in the molecular weight distribution of GPC measured by a THF-soluble component. The area ratio of the low molecular weight components shown is 15
% And a high molecular weight component having a molecular weight of 1,000,000 or more with an area ratio of 0.5 to 25%, the matching with the wax component according to the present invention becomes very good. That is, when the area ratio of the low molecular weight component having a molecular weight of 1,000 or less exceeds 15%, plasticization is rapidly accelerated by the wax component, and the above-mentioned problem becomes more remarkable. Furthermore, toner fusion to the surface of the photosensitive drum, etc.
There is also a problem in matching with the image forming apparatus. on the other hand,
When the high molecular weight component having a molecular weight of 1,000,000 or more is less than 0.5%, it is difficult to maintain a good dispersion state of the wax component, and the toner is liable to be deteriorated by an external force received from the image forming apparatus. For this reason, the developing characteristics and the storability of the toner, and the durability may be deteriorated. In particular, image fog in a low-temperature and low-humidity environment and a decrease in image density in a high-temperature and high-humidity environment become remarkable. Conversely, THF insolubles and molecular weight 10
If there are more than 100,000 high molecular weight components in excess of 25%,
In addition to impairing low-temperature fixability and toner productivity, it is difficult to uniformly disperse the toner constituent materials, so that uniform triboelectric charging of the toner cannot be obtained, and the developing characteristics deteriorate. Also,
Even if the mixing force is increased externally by hot-melt kneading etc. during toner production to improve the dispersion state, polymer chains are cut by mechanical shearing force, and balance low-temperature fixability and high-temperature offset resistance It becomes difficult. These tendencies become remarkable especially in a magnetic toner in which the particle diameter of the toner is reduced to a fine particle or magnetic particles having high specific gravity are required to be uniformly dispersed.

Further, in the binder resin component in the toner composition according to the present invention, a high molecular weight component corresponding to a region having a molecular weight of 100,000 or more in the molecular weight distribution of GPC in a THF-soluble component is a polyfunctional polymerization initiator. And / or using a polymer obtained by using a polyfunctional unsaturated monomer to achieve a high degree of low-temperature fixing property and high-temperature offset resistance, and develop the toner without breaking the balance. The characteristics, durability, and storability can be remarkably improved.

The present inventors consider the reason why the toner according to the present invention exerts the effects of the present invention as follows.

That is, gradual crosslinking soluble in THF,
Or by including the high molecular weight component having a branched structure in the toner composition, without increasing the melt viscosity of the toner at the time of heat fixing compared to the conventional crosslinkable polymer,
The elasticity of the semi-molten toner can be maintained. Further, the matching with the wax component according to the present invention is good, and the elasticity as described above is not lost even when plasticized. Thereby, the low-temperature fixing property and the high-temperature offset resistance were remarkably improved. Further, by adding a high molecular weight component having the structure as described above, a low melt viscosity portion plasticized by the volatile component or the wax component that is locally phase-separated by undergoing hot melt kneading during toner production. And the uniform mixing force can be enjoyed in the toner composition, so that the dispersion state is synergistically improved and the developing characteristics of the toner are improved. Further, since the mechanical strength of the toner can be increased, it is possible to suppress the deterioration of the toner against external force received from the image forming apparatus, and the matching with the image forming apparatus becomes easy.

In the present invention, the molecular weight distribution of the binder resin component is measured by GPC under the following conditions.

<Measurement Conditions for GPC of Resin> Apparatus: GPC-150C (manufactured by Waters) Column: KF801 to 7 (manufactured by Shodex) Column: Temperature: 40 ° C. Solvent: THF Flow rate: 1.0 ml / min. Sample: Inject 0.1 ml of a sample with a concentration of 0.05-0.6% by weight

A sample is prepared as follows.

After placing the sample in THF and leaving it to stand for several hours, it is shaken sufficiently, mixed well with THF (until the sample is no longer united), and left still for 12 hours or more. Then T
The time of leaving in HF is set to 24 hours or more.
After that, the sample processing filter (pore size 0.45
0.5 μm, for example, Myshoridisk H-25
-5 (manufactured by Tosoh Corporation, Exiclodisk 25CR manufactured by Germanic Science Japan) can be used as a GPC sample. The sample concentration is adjusted so that the resin component has the above concentration.

Measurement is performed under the above conditions, and the molecular weight of the sample is calculated using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample.

The toner composition according to the present invention has a substantially T
Preferably, it does not contain HF insolubles. Specifically, the content is 5% by weight or less, preferably 3% by weight or less based on the resin composition.

The THF-insoluble content in the present invention indicates the weight ratio of the polymer component (substantially crosslinked polymer) insoluble in the THF solvent in the resin composition in the toner.
It can be used as a parameter indicating the degree of crosslinking of the resin composition containing the crosslinking component. The THF-insoluble matter is defined by a value measured as follows.

That is, 0.5 to 1.0 g of the toner sample was weighed (W ₁ g), and a cylindrical filter paper (No.
86R), subjected to a Soxhlet extractor, extracted with 100 to 200 ml of THF as a solvent for 6 hours, and evaporated the soluble components extracted by the solvent.
After vacuum drying at 100 ° C. for several hours, 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). T
The HF insoluble content is obtained from the following equation.

[0068]

(Equation 1)

If the THF-insoluble content is more than 5% by weight, high-temperature fixing cannot be achieved at a high degree.

As a method for producing the binder resin according to the present invention, a high molecular weight polymer and a low molecular weight polymer are separately synthesized by a solution polymerization method, then they are mixed in a solution state, and then the solvent is removed. Also, a dry blending method in which the mixture is melt-kneaded by an extruder or the like, and further, a polymer component of one of a high molecular weight polymer and a low molecular weight polymer is produced by a conventionally known polymerization method or the like, and then the polymer is produced. A so-called two-stage polymerization method in which the component is dissolved in a monomer that gives the other polymer component, and this is polymerized to obtain a binder resin, is used. 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 and the like. However, when performed in the presence of a low molecular weight polymer component, In addition to the fact that the amount of the low molecular weight polymer component cannot be increased beyond the high molecular weight component, in the presence of the low molecular weight component, it is only very difficult to synthesize a sufficient high molecular weight component desired in the present invention. And disadvantages such as unnecessary low molecular weight components being formed as by-products. Conversely, it is difficult to control the degree of polymerization of low molecular weight components in the presence of high molecular weight components,
In particular, the amount of by-products having a molecular weight of 1,000 or less tends to increase, and the conversion rate of the monomer does not become sufficient, so that the residual amount of the unreacted monomer in the binder resin tends to increase. The matching with the wax component is hindered. Therefore, the solution blending method is most suitable as the method for producing the binder resin according to the present invention.

The mixing weight ratio of the low molecular weight polymer component and the high molecular weight polymer component of the binder resin according to the present invention is 30: 70-9.
The ratio is 0:10, and particularly 50:50 to 85:15 when produced by a solution blending method. That is, if the amount of the high molecular weight component is more than this range, the fixing property of the toner is deteriorated. Further, the viscosity increases during mixing of the solution, and the compatibility and dispersibility of the constituent components of the binder resin are deteriorated, and the molecular chains of the binder resin are broken. Further, even if such a binder resin and other toner constituent materials are melt-kneaded, poor dispersion and segregation of the toner constituent materials are caused. Conversely, if the amount of the high molecular weight component is less than the above range, not only the high temperature offset resistance of the toner becomes insufficient, but also the development characteristics are deteriorated.

As a method for synthesizing the high molecular weight component of the binder resin according to the present invention, 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 in an aqueous phase as small particles 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 advantageous.

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, calcium phosphate, and the like. There is an appropriate amount in terms of the amount of a monomer relative to an aqueous solvent, and generally 0.05 to 1 based on 100 parts by weight of an aqueous solvent. Used in parts by weight. The polymerization temperature is suitably from 50 to 95 ° C, but should be appropriately selected depending on the initiator used and the intended polymer.

As the high molecular weight component of the binder resin used in the present invention, in order to achieve the object of the present invention, it is preferable to use a polyfunctional polymerization initiator having a polyfunctional structure as exemplified below.

Specific examples of the polyfunctional polymerization initiator 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, 2,2-di-t -Butyl peroxybutane, 4,4
-Di-t-butylperoxyvaleric acid-n-
Butyl ester, di-t-butylperoxyhexahydroterephthalate, di-t-butylperoxyazelate, di-t-butylperoxytrimethyladipate, 2,2-bis- (4,4-di-t-butyl Peroxycyclohexyl) propane, 2,2-t-butylperoxyoctane and various polymer oxides, etc., a polyfunctional polymerization initiator having a functional group having a polymerization initiation function such as two or more peroxide groups in one molecule. And 1 such as diallyl peroxydicarbonate, t-butyl peroxymaleic acid, t-butyl peroxyallyl carbonate and t-butyl peroxyisopropyl fumarate
It is selected from a polyfunctional polymerization initiator having both a functional group having a polymerization initiation function such as a peroxide group and a polymerizable unsaturated group in a molecule.

Of these, preferred are 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, 1,1-di-t-butylperoxycyclohexane, di-t-butyl Peroxyhexahydroterephthalate, di-t-butylperoxyazelate 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 for a resin composition for a toner.
In particular, the use of a monofunctional polymerization initiator having a decomposition temperature lower than the decomposition temperature for obtaining a half-life of 10 hours of the polyfunctional polymerization initiator improves the developing characteristics of the toner.

Specifically, organic peroxides such as di-t-butyl peroxide, dicumyl peroxide, benzoyl peroxide, t-butyl peroxy-2-ethylhexanoate, t-butyl peroxybenzoate, etc. And azo compounds such as azobisisobutyronitrile and diazoaminoazobenzene, and diazo compounds.

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. The monofunctional polymerization initiator is used in an amount of 0.05 to 2 parts by weight based on 100 parts by weight of the monomer.

The high molecular weight polymer component of the binder resin used in the present invention preferably contains 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 thereof include aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; which are linked by an alkyl chain. Diacrylate compounds; for example, 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 methacrylates; diacrylate compounds linked by an alkyl chain containing an ether bond , Such as 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 instead of methacrylate 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 acrylates of the above compounds with methacrylates; further, 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.

By using these crosslinkable monomers in an amount of 1% by weight or less with respect to 100% by weight of the other monomer components, not only satisfactory low-temperature fixability and offset resistance are satisfied, but also the storage of toner. The performance is also improved.

Among these crosslinking monomers, those preferably used include aromatic divinyl compounds (particularly divinylbenzene) and diacrylate compounds linked by a chain containing an aromatic group and an ether bond. It is preferable to use it in the range of 0.001 to 0.05% by weight based on 100% by weight of the monomer component. As a result, even when the particle diameter of the toner is reduced, the developing characteristics of the developer under each environment are stabilized, and the durability is improved. Further, it shows good matching with the wax component according to the present invention.

The polymer component of the binder resin of the toner composition according to the present invention contains a monomer unit having at least one of a carboxyl group, a carboxylate group or a carboxylic anhydride group, and contains a developer. The crosslinking reaction may be promoted through a hot-melt kneading step at the time of production. In particular, when a binder resin having a low melt viscosity is used, the components constituting the developer can enjoy a stronger and more uniform shearing force than before, due to the thickening effect of the crosslinking reaction, so that they are synergistic. Not only the dispersibility is improved and the developing property is stabilized, but also the wax component according to the present invention shows good matching.

In order to exhibit a predetermined effect by the crosslinking reaction, it is preferable that a certain amount or more of the above-mentioned carboxyl group capable of forming a crosslinking bond is contained within a range that does not impair the developing characteristics. Specifically, the acid value of the polymer-side component constituting the binder resin according to the present invention is adjusted so as to be 0.5 to 30.

As the polymer component having a polar group capable of forming a cross-linking bond of the present invention, a polymer containing at least one of a carboxyl group, a carboxylic anhydride group and a carboxylate group has the best reactivity. Is shown. Examples of the carboxyl group-containing monomer for synthesizing a vinyl polymer include acrylic acid such as acrylic acid, methacrylic acid, α-ethylacrylic acid, crotonic acid and α- or β-acrylic acid thereof.
-Alkyl derivatives, fumaric acid, maleic acid, unsaturated dicarboxylic acids such as citraconic acid and its monoester derivatives or maleic anhydride, etc., such monomers alone or mixed and copolymerized with other monomers Thus, a desired polymer can be produced. Among them, it is particularly preferable to use a monoester derivative of an unsaturated dicarboxylic acid.

The carboxyl group-containing monomers usable in the present invention include, for example, monomethyl maleate, monoethyl maleate, monobutyl maleate, monooctyl maleate, monoallyl maleate,
Monoesters of α, β-unsaturated dicarboxylic acids such as monophenyl maleate, monomethyl fumarate, monoethyl fumarate, monobutyl fumarate, monophenyl fumarate, etc .; monobutyl n-butenylsuccinate, monomethyl n-octenylsuccinate, Monoesters of alkenyl dicarboxylic acids such as monoethyl n-butenylmalonate, monomethyl n-dodecenylglutarate and monobutyl n-butenyladipate; monomethyl phthalate, monoethyl phthalate, monobutyl phthalate and the like And monoesters of aromatic dicarboxylic acids.

The above-mentioned carboxyl group-containing monomer may be added in an amount of 1 to 30% by weight, preferably 3 to 20% 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 as described above is that it is not appropriate to use an acid monomer having high solubility in an aqueous suspension in the suspension polymerization. This is because it is preferable to use the compound in the form of an ester having low solubility.

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. That is, it is preferable that the carboxylic acid group or the carboxylic acid ester moiety is changed to a polar functional group by reacting with a cation component of an alkali. This is because, even if the polymer side component of the binder resin contains a carboxyl group that reacts with the metal-containing compound, 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 during the 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;
There are hydroxides of transition metals such as Zn, Ag, Pb, and Ni; 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 02-5 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 is reduced, and 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 a 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 having an acid value of 0.02 to 5 equivalents is performed, the residual cation ion concentration after the treatment is included in the range of 5 to 1000 ppm, which is preferable for defining the amount of alkali. Can be used.

To the toner according to the present invention, a metal-containing organic compound may be added in order to promote crosslinking between polymer chains of the resin composition during the production of the toner, and the toner is particularly rich in vaporization and sublimability. Those containing an organometallic compound as a ligand or counter ion give excellent results.

Among the organic compounds forming a ligand or a counter ion with a metal ion, those having the above-mentioned properties include, for example, salicylic acid, salicylamide, salicylamine, salicylaldehyde, salicylosalicylic acid, ditert Salicylic acid such as -butylsalicylic acid and derivatives thereof, for example, β-diketones such as acetylacetone and propionacetone, and low-molecular carboxylate salts such as acetate and propionic acid.

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 low molecular weight polymer can be obtained by increasing the 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 radical chain transfer depending on the solvent and adjusting the amount of the polymerization 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, a solution polymerization method under a pressurized condition is also effective in minimizing the amount of the polymerization initiator used and minimizing the influence of the residue of the polymerization initiator.

Examples of the monomer for obtaining the high-molecular component of the binder resin used in the toner of the present invention and the monomer for obtaining the low-molecular component are as follows.

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 such as p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene and derivatives thereof; ethylene , 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, Vinyl esters such as vinyl benzoate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, methacrylic acid Stearyl, meta Phenyl acrylic acid, dimethylaminoethyl methacrylate, alpha-methylene aliphatic monocarboxylic acid esters such as diethylaminoethyl methacrylate;
Methyl acrylate, ethyl acrylate, acrylic acid n-
Butyl, isobutyl acrylate, propyl acrylate,
Acrylic esters such as n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate and phenyl acrylate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and methyl isopropenyl ketone; N-vinyl pyrrole, N-vinyl carbazole, N
N- such as vinylindole and N-vinylpyrrolidone
Vinyl compounds of vinyl compounds; vinyl naphthalenes; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, and acrylamide; used alone or in combination of two or more.

These binder resin components are preferably mixed and dispersed in advance with the wax component before producing the toner. In particular, a method is preferred in which the low molecular weight wax component and the high molecular weight polymer are preliminarily dissolved in a solvent during the production of the binder, and then mixed with the low molecular weight polymer solution. By preliminarily mixing the low molecular weight wax component and the high molecular weight component, phase separation in the micro region is reduced, the high molecular weight component is not re-aggregated, and a good dispersion state with the low molecular weight component is obtained.

The solid concentration of the polymer solution is determined by the dispersion efficiency,
In consideration of prevention of deterioration of the resin at the time of stirring, operability, etc., 5 to 70
It is preferably not more than 5% by weight, the preliminary solution of the high molecular weight polymer component and the low molecular weight wax component is preferably 5% to 60% by weight, and the low molecular weight polymer solution is preferably 5% to 70% by weight.

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

Next, the method of mixing the low molecular weight polymer solution is to add 10 to 1000 parts by weight of the low molecular weight polymer solution to the solid content of the preliminary solution and perform stirring and mixing. But it can be continuous.

The organic solvent used when mixing the solution of the resin composition according to the present invention includes, for example, benzene, toluene,
Xylol, solvent naphtha 1, solvent naphtha 2, solvent naphtha 3, cyclohexane, ethylbenzene, hydrocarbon solvents such as Solvesso 100, Solvesso 150, mineral spirits, methanol, ethanol, iso-propyl alcohol, n-butyl alcohol, alcohol solvents such as sec-butyl alcohol, iso-butyl alcohol, amyl alcohol and cyclohexanol; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; and ester solvents such as ethyl acetate, n-butyl acetate and cellosolve acetate. Solvents include ether solvents such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, and methyl carbitol. Aromatic in these,
Ketone and ester solvents are preferred. They may be used in combination.

It is preferable to remove the organic solvent by heating the organic solvent solution of the polymer, removing 10 to 80% by weight of the organic solvent under normal pressure, and then removing the remaining solvent under reduced pressure. At this time, the organic solvent solution needs to be maintained at a temperature not lower than the boiling point of the used organic solvent and not higher 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, Causes phase separation. If the temperature exceeds 200 ° C., the depolymerization of the polymer proceeds, and not only oligomer formation due to molecular cleavage, but also incorporation of residual monomers into the product resin due to monomer generation, which is unsuitable as an electrophotographic toner binder Becomes

A wax component is preliminarily mixed with a binder resin component.
When dispersed, volatile components in the binder resin component,
It is controlled to less than 0.2% by weight. When the residual amount of the volatile component is 0.2% by weight or more, not only the above-mentioned problem caused by plasticization occurs but also the storage stability of the binder resin itself is affected.

The resin composition for a toner obtained by the above production method is excellent in the compatibility between the low molecular weight polymer and the high molecular weight polymer, not to mention the dispersibility of the low molecular weight wax component, and compared with the conventional method. Thus, significant improvements are made.

The glass transition temperature (Tg) of the resin composition contained in the toner according to the present invention is adjusted to be 50 to 70 ° C. When Tg is lower than 50 ° C., it causes deterioration of the developer in a high-temperature atmosphere and offset during heating and fixing. On the other hand, if the temperature exceeds 70 ° C., the overall fixing property is adversely affected.

In the present invention, the Tg of the resin was measured using a differential thermal analyzer (DSC analyzer), DSC-7 (manufactured by PerkinElmer).

The measurement sample is 5 to 20 mg, preferably 10
Weigh the mg precisely. This is put in an aluminum pan, and an empty aluminum pan is used as a reference, and measurement is performed at a temperature increasing rate of 10 ° C./min under normal temperature and normal humidity using an empty aluminum pan as a reference. During this heating process, a temperature of 40 to 100
An endothermic peak of the main peak in the range of ° C is obtained. The intersection between the line at the midpoint of the baseline before and after the endothermic peak appeared and the differential heat curve was obtained.

In the toner of the present invention, it is preferable to add a charge control agent in order to improve charge stability and developability.

Specific examples of the positive charge control agent include generally nigrosine, an azine dye having an alkyl group having 2 to 16 carbon atoms (Japanese Patent Publication No. 42-1627), and a basic dye (for example, CI Basic Yellow). 2 (CI.41
000), C.I. I. Basic Yellow 3, C.I.
I. Basic Red 1 (CI. 45160),
C. I. Basic Red 9 (CI.4250
0), C.I. I. Basic Violet 1 (CI.
42535), C.I. I. Basic Violet 3
(CI. 42555), C.I. I. Basic Violet 10 (CI. 45170), C.I. I. Basic Violet 14 (CI. 42510), C.I.
I. Basic Blue 1 (CI. 42025),
C. I. Basic Blue 3 (CI.5100
5), C.I. I. Basic Blue 5 (CI.421
40), C.I. I. Basic Blue 7 (CI.4
2595), C.I. I. Basic Blue 9 (C.I.
I. 52015), C.I. I. Basic Blue 24
(CI. 52030), C.I. I. Basic Blue 25 (CI.52025), C.I. I. Basic Blue 26 (CI.44025), C.I. I. Basic Green 1 (CI. 42040), C.I. I. Basic Green 4 (CI.42000), etc.
Lake pigments of these basic dyes (as the lacking agent, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.),
C. I. Solvent Black 3 (CI. 2615)
0), Hansa Yellow G (CI. 11680), C.I.
I. Mordrant Black 11, C.I. I. Pigment Black 1 and the like.

Further, for example, polyamide resins such as quaternary ammonium salts such as benzolmethyl-hexadecylammonium chloride and decyl-trimethylammonium chloride, vinyl polymers having an amino group, and condensation polymers having an amino group can be used. Preferably, nigrosine, a quaternary ammonium salt, a triphenylmethane-based nitrogen-containing compound, polyamide or the like is used.

Specific examples of the negative charge control agent include JP-B-41-20153, JP-B-42-27596, and JP-B-42-27596.
Metal complexes of monoazo dyes described in JP-A-4-6397 and JP-A-45-26478;
Nitroamine acids and salts thereof described in JP-A-33338; I. Dyes and pigments such as 14645;
No. 42755, No. 58-41508, No. 5
No. 8-7384, JP-B-59-7385 and the like, Z of salicylic acid, naphthoic acid and dicarboxylic acid.
Examples include metal complexes such as n, Al, Co, Cr, and Fe; sulfonated copper phthalocyanine pigments; styrene groups having nitro groups and halogens; and chlorinated paraffins. In particular, from the viewpoint of dispersibility, the general formula [I]
And an organic metal complex of a basic organic acid represented by the general formula [II] are preferable.

[0117]

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[0118]

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[0119]

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Specific examples of the azo metal complex [I] and the basic organic acid metal complex [II] are shown below.

[0121]

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[0122]

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[0123]

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[0124]

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[0125]

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[0126]

Embedded image

[0127]

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[0128]

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[0129]

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[0130]

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[0131]

Embedded image

[0132]

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[0133]

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[0134]

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[0135]

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[0136]

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[0137]

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These metal complexes can be used alone or in combination of two or more.

When the above-mentioned metal complex is used as a charge controlling agent, the amount of addition is maintained as described above, while maintaining good triboelectricity, while reducing the developing power and environmental stability due to the contamination of the developing sleeve surface by the charge controlling agent. 100 parts by weight of the binder resin to minimize the adverse effects
An addition amount of 0.1 to 5 parts by weight is preferred.

In the toner of the present invention, charging stability,
In order to improve developability, fluidity and durability, it is preferred to add an inorganic fine powder.

Examples of the inorganic fine powder used in the present invention include:
For example, fine silica powder, titanium oxide, alumina and the like can be mentioned. Among them, the specific surface area by nitrogen adsorption measured by the BET method is 30 m ² / g or more (particularly 50 to 400 m ² / g).
Those within the range give good results. It is preferable to use 0.01 to 8 parts by weight, preferably 0.1 to 5 parts by weight of the inorganic fine powder with respect to 100 parts by weight of the toner.

Further, the inorganic fine powder used in the present invention includes:
Silicon varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, silane coupling agents, silane coupling agents having functional groups, and other organosilicon compounds for purposes such as hydrophobicity and charge control, if necessary It is also preferred that the composition is treated with such a treating agent or in combination with various treating agents.

As other additives, for example, lubricants such as Teflon, zinc stearate, and polyvinylidene fluoride, among which polyvinylidene fluoride are preferable. Or an abrasive such as cerium oxide, silicon carbide, strontium titanate,
Among them, strontium titanate is preferable. Alternatively, for example, a fluidity imparting agent such as titanium oxide and aluminum oxide, particularly a hydrophobic agent is preferable. Anti-caking agent,
Alternatively, for example, a conductivity imparting agent such as carbon black, zinc oxide, antimony oxide, and tin oxide, or small particles of white and black fine particles of opposite polarity can be used as a developing property improver.

Further, when the toner of the present invention is used as a two-component developer, it is used by mixing with a carrier powder.
In this case, the mixing ratio of the toner and the carrier powder is 0.1 to 50% by weight as a toner concentration, preferably 0.5 to 1%.
0% by weight, more preferably 3 to 5% by weight is desirable.

As the carrier which can be used in the present invention, all known carriers can be used. For example, magnetic powders such as iron powder, ferrite powder and nickel powder, glass beads, etc. Those treated with a resin, a vinyl-based resin, a silicon-based resin, or the like can be given.

Further, the toner of the present invention can be used as a magnetic toner by further containing a magnetic material. In this case, the magnetic material also serves as a colorant. Examples of the magnetic material contained in the magnetic toner of the present invention include iron oxides such as magnetite, hematite, and ferrite; metals such as iron, cobalt, and nickel; or aluminum, cobalt, copper, lead, magnesium, and tin of these metals. Zinc, antimony,
Examples include alloys of metals such as beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, and vanadium, and mixtures thereof.

The magnetic material has a bulk density of 0.35 g / c.
m ³ or more and an average particle size of about 0.1 to 2 μm, preferably about 0.1 to 0.5 μm. The amount contained in the toner is about 20 to 200 parts by weight per 100 parts by weight of the resin component. It is preferably from 40 to 150 parts by weight per 100 parts by weight of the resin component. In the present invention, the bulk density of the magnetic material is defined as JIS (Japanese Industrial Standard) K
It refers to the value measured at -5101.

The magnetic characteristics when a 10K Oersted was applied were such that the coercive force was 20 to 250 Oersted, the saturation magnetization was 50 to 250 Oersted.
Desirable is 200 emu / g and residual magnetization of 2 to 20 emu / g.

As the colorant that can be used in the toner of the present invention, any suitable pigment or dye can be used. Toner colorants are well known and include, for example, pigments such as carbon black, aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, bengalara, phthalocyanine blue, and indanthrene blue. These are used in amounts necessary and sufficient to maintain the optical density of the fixed image.
0.1 to 20 parts by weight, preferably 2 to 10 parts by weight per part by weight
Good addition amount by weight. A dye is further used for the same purpose. For example, azo dyes, anthraquinone dyes,
There are xanthene dyes, methine dyes and the like, and 0.1 to 20 parts by weight, preferably 0.3 to
The addition amount of 3 parts by weight is good.

To prepare the toner for developing an electrostatic image according to the present invention, a binder resin, a metal compound, a pigment or dye as a colorant, a magnetic substance, a charge controlling agent, and other additives as necessary are used. , Henschel mixer, after sufficiently mixed by a mixer such as a ball mill, heated roll, kneader, using a hot kneader such as an extruder, melting, kneading and kneading the metal compound in the binder resin, pigment,
The toner according to the present invention can be obtained by dispersing or dissolving the dye and the magnetic substance, and solidifying by cooling, followed by pulverization and classification.

Further, if necessary, desired additives are sufficiently mixed by a mixer such as a Henschel mixer to obtain the toner for developing an electrostatic image according to the present invention.

In the method for producing a toner composition according to the present invention, if the residual amount of the volatile component before and after the dispersion of the wax in the toner composition is controlled as described above, a general method in the melt-kneading step is used. Although it is possible to use a suitable kneading method, in particular, in order to obtain good dispersibility with other additives as described above without impairing the performance of the wax component according to the present invention, uniaxial or biaxial mixing is preferred. An extruder with an axial screw is used. Particularly, an extruder method is preferable. In this case, the ratio (L / D) of the length (L) and the diameter (D) of the kneading shaft of the extruder is set to 10 to 60.
And melt kneading. This draws out a synergistic plasticizing effect of the wax component and the volatile component in the toner composition at the time of melt-kneading, and quickly eliminates the difference in viscosity between the locally melted high-melt viscosity portion of the toner-kneaded material. Therefore, a good dispersion state can be achieved. At the same time, even if the mixing force is externally increased during melt-kneading, the breaking of the molecular chains of the binder resin due to the mechanical shearing force is prevented. Furthermore, by specifying the configuration of the polymer side component of the binder resin, reaggregation can be prevented without impairing the leakiness between the respective toner components, so that the dispersion state is significantly improved. When kneading with an L / D of less than 10, the melt viscosity of the binder resin is not sufficiently reduced, so that the plasticizing effect of the wax component and the volatile component is not enjoyed, and the dispersion state is not improved, and the toner after production is not improved. It becomes difficult to control the amount of residual volatile components in the composition,
As described above, there is a problem caused by poor dispersion of the wax component. When the L / D is more than 60, the melt viscosity of the binder resin is reduced more than necessary, so that only the periphery of the wax component is rapidly plasticized, and poor dispersion of other additives and the binder resin. Phase separation or the like may occur. These tendencies become more remarkable when, for example, a magnetic toner containing an additive having a large specific gravity difference from a binder resin such as a magnetic material is manufactured, and the L / D is 15 to 15.
Limited to 55.

At the time of melt-kneading, the melt-kneading is performed at a temperature not lower than 20 ° C. and not higher than 70 ° C. than the maximum endothermic peak temperature in the DSC curve of the wax component.

By melt-kneading at a temperature lower by 20 ° C. than the melting point of the wax, the wax component finely dispersed in the binder resin is first heat-melted, and the melt viscosity of the binder resin at the time of melt-kneading is improved. This is because the shearing force higher than the force required for dispersing the constituent components of the lowering toner is suppressed from being applied to the binder resin, so that the molecular chains of the binder resin, particularly the polymer chains, can be prevented from being cut. If the kneading is performed at a temperature lower than the melting point of the wax by 20 ° C. or less, the shearing force is strongly applied to the binder resin before the wax is melted by heat, so that the polymer chains may be cut.

When melt-kneading is performed at a temperature 70 ° C. higher than the melting point of the wax, the melt viscosity of the wax component is extremely lowered, and at the same time, the melt viscosity of the binder resin is lowered more than necessary. Poor dispersion of other materials (charge control agent, coloring agent, magnetic material, etc.) may occur.

That is, melt kneading at a temperature not lower than the melting point of the wax by 20 ° C., preferably not lower than the melting point of the wax and not higher than the melting point of the wax by 60 ° C., preferably not higher than the melting point of the wax by 50 ° C. Good for preventing dispersion and molecular chain breakage.

In addition, a toner with less residual monomer and residual solvent can be obtained by sucking air through a vent port of an extruder or the like during melt-kneading. In addition, it is effective that the solvent is easily removed from the binder resin by blending the wax component with the binder resin in advance.

As described above, by specifying the toner production conditions at the time of melt-kneading, the dispersion state of the constituent components in the toner composition is increased, and the change in the molecular weight of the binder resin is kept to a minimum. Becomes possible. As a result, various properties of the toner can be achieved to a high degree without impairing the characteristics of the individual toner constituent materials described above even after the toner is formed.

Next, an example of the image forming method according to the present invention will be described with reference to the schematic diagram of FIG.

Reference numeral 10 denotes a rotating drum type electrostatic latent image carrier (hereinafter, referred to as a photoconductor). The photoconductor 1 includes a conductive base layer 10b such as aluminum, and a photoconductive layer 10a formed on the outer surface thereof. Is a basic constituent layer, and is rotated at a predetermined peripheral speed (process speed) clockwise in the drawing.

Reference numeral 11 denotes a charging roller as a contact charging means, which has a basic structure including a central core 11b and a conductive elastic layer formed on the outer periphery thereof. Charging roller 1
1 is pressed against the surface of the photoconductor 10 with a pressing force, and is driven to rotate as the photoconductor 10 rotates. V ₁ is the charging roller 1
1 is a charging bias power supply for applying a voltage to the photosensitive member 1, and a bias is applied to the charging roller 11 to
The zero surface is charged to a predetermined polarity / potential. Next, an electrostatic latent image is formed by image exposure 14, and is sequentially visualized as a toner image by developing means 16 holding toner.

Reference numeral 19 denotes a transfer roller as a contact transfer means, which basically has a core 19b at the center and a conductive elastic layer 19a formed on the outer periphery thereof. The transfer roller 19 is pressed against the surface of the photoconductor 10 with a pressing force at least at the time of transfer via the recording material P, and rotates the photoconductor 10 at a constant speed or at a different speed from the peripheral speed. Recording material P is on the photosensitive member 10 by applying a is at the same time, the bias of triboelectricity opposite polarity of the toner to the transfer roller 19 conveyed between the transfer roller 19 and the photoreceptor 10 from a transfer bias power supply V ₂ The toner image is transferred to the front side of the recording material P.

Next, the recording material P is conveyed to a fixing device H having a heating roller Ha having a built-in halogen heater and an elastic pressure roller Hb pressed against the roller with a pressing force. The toner image is fixed by passing through the gap. Photoconductor 10 after transfer of toner image
On the surface side, adhered contaminants such as untransferred toner are removed from the photosensitive member 1.
The surface is cleaned by a cleaning device 13 provided with an elastic cleaning blade pressed against the counter direction 0, and the charge is removed by a charge removing exposure device 30 to repeatedly form an image. Further, a method of fixing with a heater via a film may be used.

In an image forming apparatus having such a contact charging means or a contact transfer means, uniform charging and sufficient transfer of the photosensitive member can be performed with a relatively low voltage bias as compared with corona charging or corona transfer. Therefore, it is excellent in miniaturization of the discharger itself and suppression of corona discharge products such as ozone.

Other contact charging means include a method using a charging blade and a method using a conductive brush. While these contact charging means have the effect of making high voltage unnecessary and reducing the generation of ozone,
Generally, since the member comes into direct contact with the photoreceptor, the problem of toner fusion is likely to occur. However, the use of the toner of the present invention is preferable because such problems do not occur. The present invention does not limit the method and effect of the contact charging means to which the present invention is applied, and any method of charging a member by directly contacting the member with the photoreceptor is applicable to the present invention. It is possible.

The preferable process conditions when the charging roller is used are that the contact pressure of the roller is 5 to 500 g / c.
m, when a voltage obtained by superimposing an AC voltage on a DC voltage is used, AC voltage = 0.5 to 5 kVpp, AC frequency = 50
５5 kHz, DC voltage = ± 0.2〜 ± 1.5 kV, and when DC voltage is used, DC voltage = ± 0.2〜 ±
5 kV.

The material of the charging roller and the charging blade is preferably a conductive rubber, and a release coating may be provided on the surface thereof. Nylon resin,
PVDF (polyvinylidene fluoride), PVDC (polyvinylidene chloride) and the like are applicable.

As the material of the transfer rotary member applicable to the present invention, the same material as that of the charging roller can be used. Preferred transfer process conditions are that the contact pressure of the roller is 5 to 500 g / cm. , DC voltage ± 0.2 ~
± 10 kV.

[0169]

EXAMPLES The present invention will be described below with reference to specific examples, but the present invention is not limited to these examples.

Table 1 summarizes the contents of the wax components used in the present invention, together with the DSC measurement results and the GPC measurement results.

That is, 75 C of higher alcohol of C ₅₀
polyethylene wax A containing t% (invention), C ₃₀
Wax (B) (invention) containing 62 wt% of higher alcohols, 67 wt% of higher aliphatic acids of C ₅₀
% Of polyethylene wax C (invention), wax D obtained by separating hydrocarbons synthesized by the Arage method, waxes E and C obtained by separating hydrocarbons polymerized at low pressure by Ziegler catalyst Wax a containing ₂₂ higher alcohols as a main component (Comparative Example),
A wax b (comparative example) obtained by pyrolysis of polyethylene and a wax c (comparative example) obtained by pyrolysis of polypropylene.

[0172]

[Table 1]

[Production Example 1 of Resin Composition] 300 parts by weight of xylene was charged into an autoclave made of a synthetic glass of a low molecular weight polymer (L-1), and the inside of the vessel was sufficiently purged with nitrogen while stirring.
It sealed and heated up to 200 degreeC.

A mixture of 87 parts by weight of styrene, 13 parts by weight of n-butyl acrylate, and 2 parts by weight of di-tert-butyl peroxide was added for 2.5 hours while maintaining a pressurized reflux state at the same temperature. After the dropwise addition, the mixture was held for 1 hour to complete the polymerization, thereby obtaining a low molecular weight polymer (L-1) solution.

A part of this polymer solution was taken out, dried under reduced pressure, and the obtained low molecular weight polymer (L-1) was analyzed. Mw = 8,500, Mn = 4,300, P
Mw = 7,000 and Tg = 60 ° C.

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 then 68 parts by weight of styrene and acrylic acid 27 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-
A mixture of 0.1 part by weight of tert-butylperoxycyclohexyl) propane (10-hour half-life 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 (10-hour half-life temperature; 72 ° C.) was further added. Furthermore,
The polymerization was completed by holding for 12 hours.

To the suspension after completion of the reaction, an aqueous NaOH solution equivalent to twice the acid value (AV = 8.0) 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.
n = 110,000, PMw = 1.2 million, and Tg = 60 ° C.

Preparation Example of Binder In a four-necked flask, 100 parts by weight of xylene, 25 parts by weight of the high molecular weight polymer (H-1), and the wax component A (having a typical structural formula of CH ₃ (CH ₂ 7 parts by weight of a higher alcohol wax represented by ₄₈ CH ₂ OH), and the mixture is heated, stirred under reflux and pre-dissolved. After maintaining in this state for 12 hours, a uniform pre-solution (Y-1) of the high molecular weight polymer (H-1) and the wax component A was obtained. The Tg of the solid content in this pre-dissolved solution was 55 ° C.

After mixing the above pre-dissolved solution (Y-1) and 260 parts by weight of the homogeneous solution of the low molecular weight polymer (L-1) under reflux, the solvent was distilled off, and the obtained resin was cold rolled. After solidification, the mixture was pulverized to obtain a resin composition for toner (I). When the molecular weight of the resin composition (I) was measured, it was 7,000 and 110
Mw / Mn was 47 and Tg was 56 ° C.

The resin composition (I) had a volatile component content of 0.11% by weight, a residual xylene content of 890 ppm,
The amount of unreacted styrene was 80 ppm.

Further, when the thin section of the resin composition was observed with a video microscope (manufactured by Wilson), it was confirmed that the resin composition did not re-aggregate and was very well dispersed.

[Preparation Example 2 of Resin Composition] Preparation Example of Binder 100 parts by weight of xylene and 25 parts by weight of the high molecular weight polymer (H-1) were charged into a four-necked flask, and the temperature was raised to reflux. The mixture was stirred under the following conditions for 12 hours to obtain a uniform solution of the high molecular weight polymer (H-1).

The above solution was mixed with the low molecular weight polymer (L-
After mixing with 260 parts by weight of the homogeneous solution of 1) under reflux, the solvent was distilled off, and the obtained resin was cold-rolled, solidified and pulverized to obtain a resin composition for toner (II).

When the molecular weight of the resin composition (II) was measured, it had peaks at 7,000 and 1,000,000, and Mw /
Mn was 48 and Tg was 60 ° C.

The amount of volatile components in the resin composition (II) was 0.22% by weight, and the amount of residual xylene was 1,600 pp.
m, the amount of unreacted styrene was 250 ppm.

[Production Example 3 of Resin Composition] 300 parts by weight of xylene was put into an autoclave made of a synthetic glass of a low molecular weight polymer (L-2), and the inside of the vessel was sufficiently purged with nitrogen while stirring.
It sealed and heated up to 200 degreeC.

While maintaining the pressurized reflux condition at the same temperature, 70 parts by weight of styrene and di-tert-butyl peroxide 2
A part by weight of the mixed solution was added dropwise over 2.5 hours, and then maintained for 1 hour to complete the polymerization, thereby obtaining a low molecular weight polymer (L-2) solution.

A part of the polymer solution was taken out, dried under reduced pressure, and the obtained low molecular weight polymer (L-2) was analyzed. Mw = 3,500, Mn = 2,500, P
Mw = 3,000, Tg = 60 ° C.

Synthesis of High Molecular Weight Polymer (H-2) 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 then 77 parts by weight of styrene and acrylic acid 23 parts by weight of n-butyl, 0.001 parts by weight of divinylbenzene, and 1.1 parts by weight
-Bis (di-tert-butylperoxy) 3,3,5
Trimethylcyclohexane (10 hour half-life temperature; 9
(0 ° C.) 0.1 part by weight of a mixed solution 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 (10-hour half-life temperature; 72 ° C.) was further added. Furthermore,
The polymerization was completed by holding for 12 hours.

The high molecular weight polymer (H-2) was separated by filtration, washed with water, dried and analyzed.
n = 150,000, PMw = 800,000, Tg = 60 ° C.

Preparation of Binder A solution of the high molecular weight polymer (H-2) was prepared in the same manner as in Production Example 2 of the resin composition described above, and the low molecular weight polymer (L-
2) After mixing with 290 parts by weight of the solution under reflux, the solvent was distilled off, and the obtained resin was cold-rolled, solidified and pulverized to obtain a resin composition for toner (III).

When the molecular weight of the resin composition (III) was measured, it had peaks at 3,100 and 800,000 and Mw /
Mn was 48 and Tg was 58 ° C.

The resin composition (III) had a volatile component content of 0.26% by weight and a residual xylene content of 1,800 p
pm, and the amount of unreacted styrene was 390 ppm.

[Production Example 4 of Resin Composition] Production of Binder 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, and then heated to a reflux temperature. .

While maintaining the reflux state at the same temperature, styrene 4
4 parts by weight, 6 parts by weight of n-butyl acrylate, and
1,1-bis (di-tert-butylperoxy) 3,
A mixture of 2 parts by weight of 3,5-trimethylcyclohexane was added dropwise over 4 hours, and then polymerized for 1 hour. afterwards,
20 parts by weight of styrene, n-butyl acrylate 5
Parts by weight and further 3 parts by weight of tert-butylperoxy-2-ethylhexanoate were added, and after additional polymerization, the solvent was distilled off. The obtained resin was cold-rolled, solidified and then pulverized. A resin composition for toner (IV) was obtained.

When the resin composition for toner (IV) was analyzed, it had a peak at 25,000, formed a shoulder at 150,000, Mw / Mn was 16, and Tg was 60 ° C.

The volatile component of the resin composition (IV) was 0.37% by weight, and the residual xylene content was 2,600 pp.
m, and the amount of unreacted styrene was 800 ppm.

[Production Example 5 of Resin Composition] Production of Binder After putting 300 parts by weight of degassed water and 20 parts by weight of a 2% by weight aqueous solution of polyvinyl alcohol into a four-necked flask, the low molecular weight polymer (L -2) 50 parts by weight, styrene 75
Parts by weight, n-butyl acrylate 24 parts by weight, divinylbenzene 1 part by weight, and benzoyl peroxide 4
A part by weight of the mixed solution was added and stirred to form a suspension.

After the inside of the flask was sufficiently replaced with nitrogen, 8
The temperature was raised to 5 ° C. to initiate polymerization. The same temperature was maintained for 20 hours to obtain a pearl-shaped resin composition (V).

When the molecular weight of the resin composition (V) was measured, it had a peak at 3,000, formed a shoulder at 110,000, Mw / Mn was 22, and Tg was 63 ° C.

Further, since the amount of volatile components in the resin composition (V) was 0.5% by weight, steam distillation and drying under reduced pressure were repeated to obtain a volatile component of 0.04% by weight and unreacted styrene 1
70 ppm and the amount of benzaldehyde were 20 ppm.

[Comparative Production Example 1 of Resin Composition] 77 parts by weight of synthetic styrene of low molecular weight polymer (L-3), 23 parts by weight of n-butyl acrylate, and 2 parts by weight of di-tert-butyl peroxide Production Example 3 described above: low molecular weight polymer (L-
A low molecular weight polymer (L-3) was obtained in the same manner as in the synthesis of 2).

A part of this polymer solution was taken out, dried under reduced pressure, and the obtained low molecular weight polymer (L-3) was analyzed. Mw = 35,000, Mn = 20,000,
PMw = 30,000 and Tg = 58 ° C.

Synthesis of High Molecular Weight Polymer (H-3) 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 then 77 parts by weight of styrene and acrylic acid A mixed solution of 23 parts by weight of n-butyl and 0.1 parts by weight of benzoyl peroxide was added and stirred to form a suspension.

After the inside of the flask was sufficiently purged with nitrogen, 8
The temperature was raised to 0 ° C. to initiate polymerization. The polymerization was completed by maintaining the same temperature for 36 hours.

The high molecular weight polymer (H-3) was separated by filtration, washed with water, dried and analyzed. Mw = 960,000, Mn
= 450,000, PMw = 600,000, and Tg = 60 ° C.

Preparation of Binder In a four-necked flask, 100 parts by weight of xylene, 75 parts by weight of the above low molecular weight polymer (L-1), and a high molecular weight polymer (H
-3) 25 parts by weight were added, and the mixture was heated and stirred under reflux for 12 hours, mixed, then the organic solvent was distilled off, and the obtained resin was cold-rolled, solidified and then pulverized to obtain a comparative resin composition. (I) was obtained.

When the molecular weight of the comparative resin composition (i) was measured, it had peaks at 30,500 and 500,000,
w / Mn was 29 and Tg was 59 ° C.

The comparative resin composition (i) had a volatile component of 0.44% by weight and a residual xylene content of 3,300%.
ppm, and the amount of unreacted styrene was 670 ppm.

[Comparative Production Example 2 of Resin Composition] Synthetic low-molecular-weight polymer (L-4) 77 parts by weight of styrene, 23 parts by weight of n-butyl acrylate, and 2 parts by weight of di-tert-butyl peroxide Of the above-mentioned Production Example 3: low molecular weight polymer (L-
A low molecular weight polymer (L-3) was obtained in the same manner as in the synthesis of 2).

A part of this polymer solution was taken out, dried under reduced pressure, and the obtained low molecular weight polymer (L-4) was analyzed. Mw = 20,000, Mn = 8,000,
PMw was 10,000 and Tg was 58 ° C.

Synthesis of high molecular weight polymer (H-4) 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 then 77 parts by weight of styrene and acrylic acid A mixed solution of 23 parts by weight of n-butyl and 0.1 parts by weight of benzoyl peroxide was added and stirred to form a suspension.

After sufficiently replacing the inside of the flask with nitrogen, 8
The temperature was raised to 0 ° C. to initiate polymerization. The polymerization was completed by maintaining the same temperature for 36 hours.

The high molecular weight polymer (H-4) was separated by filtration, washed with water, dried, and analyzed.
= 300,000, PMw = 400,000, and Tg = 60 ° C.

Binder Production In a four-necked flask, 100 parts by weight of xylene, 75 parts by weight of the above low molecular weight polymer (L-1), and a high molecular weight polymer (H
-3) 25 parts by weight were added, the mixture was heated, stirred under reflux for 12 hours, mixed, then the organic solvent was distilled off, and the obtained resin was cold-rolled, solidified and pulverized, and then pulverized. ii) was obtained.

When the molecular weight of the comparative resin composition (ii) was measured, it had peaks at 30,500 and 300,000,
Mw / Mn was 29 and Tg was 55 ° C.

The comparative resin composition (ii) had a volatile component of 0.31% by weight and a residual xylene content of 2,10%.
0 ppm and the amount of unreacted styrene was 600 ppm.

[Comparative Production Example 3 of Resin Composition] Synthesis of High Molecular Weight Polymer (H-5) Into a four-necked flask, 180 parts by weight of degassed water and 20 parts by weight of a 2% by weight aqueous solution of polyvinyl alcohol were charged. Thereafter, a mixed solution of 77 parts by weight of styrene, 23 parts by weight of n-butyl acrylate, and 0.1 part by weight of benzoyl peroxide was added and stirred to form a suspension.

After sufficiently replacing the inside of the flask with nitrogen, 8
The temperature was raised to 0 ° C. to initiate polymerization. The polymerization was completed by maintaining the same temperature for 36 hours.

The high molecular weight polymer (H-5) was separated by filtration, washed with water, dried and analyzed. Mw = 960,000, Mn
= 50,000, PMw = 600,000, and Tg = 60 ° C.

Preparation of Binder In a four-necked flask, 900 parts by weight of toluene, 150 parts by weight of the high molecular weight polymer (H-5), and the wax component a (represented by CH ₃ (CH ₂ ) ₁₈ CH ₂
90 parts by weight of a higher alcohol wax represented by OH) are charged, the atmosphere in the flask is sufficiently replaced with nitrogen while stirring, and the temperature is raised to reflux.

Under reflux, a solution in which 400 parts by weight of styrene, 50 parts by weight of n-butyl acrylate, and 3 parts by weight of azobisisobutyronitrile were dissolved was added dropwise over 2.5 hours to carry out solution polymerization. went.

After further polymerization for 4 hours, the organic solvent was distilled off, and the obtained resin was cold-rolled, solidified and pulverized to obtain a comparative resin composition (iii).

The volatile component of the comparative resin composition (iii) was 0.53% by weight, and the residual xylene was 3,400%.
ppm, and the amount of unreacted styrene was 1,300 ppm.

[Production Example 1 of Toner] 100 parts by weight of resin composition (I) obtained in Production Example 1 of resin composition 7 parts by weight of wax component (A) 100 parts by weight of magnetic fine powder 100 parts by weight Load control agent (Azo dye based iron complex: complex [I] -7) 2 parts by weight

After uniformly premixing the above materials,
The mixture was melted and kneaded with a twin-screw extruder heated to ℃.
At this time, the L / D of the extruder was 35.
After cooling, the kneaded product was coarsely pulverized by a hammer mill and further finely pulverized by a jet mill, and the obtained pulverized product was classified by wind power to obtain a classified powder (1) having a weight average diameter of 6.5 μm.

[Toner Production Examples 2 to 8 and Comparative Production Examples 1 to 4] The resin composition (II) obtained in the above resin composition production example
To (V), and 100 parts by weight of each of the comparative resin compositions (i) to (iii) obtained in Comparative Production Examples, 7 parts by weight of the wax components described in Table 1 and 7 parts by weight of the magnetic fine powder. 100
After uniformly mixing 2 parts by weight of a negative charge control agent (azo dye-based iron complex: complex [I] -7), the mixture was melt-kneaded with a biaxial extruder. After cooling the kneaded product, classified powders (2) to (8) having a weight average diameter of 6.5 μm and comparative classified powders (9) to (12) were obtained in the same manner as in Production Example 1 of the toner. .

Table 2 summarizes the prescription contents and production conditions of the above-mentioned classified powder for toner.

[0232]

[Table 2]

1.2 parts by weight of a hydrophobic oil-treated silica fine powder (BET) was added to 100 parts by weight of each of these classified powders.
Specific surface area: 200 m ² / g) and dry-mixing the toners (1) to (8) and the comparative toners (9) to (1).
2) was obtained.

[Toner Production Example 9 and Comparative Production Example 5] The resin composition (I) obtained in the above-described resin composition production examples and the comparative resin composition obtained in the comparative production examples (Iii) 100 parts by weight of carbon black (B)
(ET specific surface area: 130 m ² / g) 5 parts by weight, 3 parts of negative charge control agent (azo dye-based iron complex: complex [II] -1)
A classified powder having a weight average diameter of 6.2 μm and a classified powder for comparison were obtained in the same manner as in the above-mentioned toner production example, except that the mixture was melt-kneaded with a uniaxial extruder having an L / D of 40 using parts by weight.

To 100 parts by weight of each of these classified powders, 1.5 parts by weight of a hydrophobic titanium oxide fine powder (BET specific surface area: 150 m ² / g) was dry-mixed, and toner (13),
In addition, a comparative toner (14) was obtained.

Table 3 summarizes the measurement results of the volatile components, molecular weight components, and THF-insoluble components of the toners obtained in the above Production Examples and Comparative Production Examples.

[0237]

[Table 3]

Next, the image forming apparatus used in this embodiment will be described. In this example, a commercially available laser beam printer LBP-PX (manufactured by Canon) was used under the following conditions.

A preferred specific example of the image forming apparatus is shown in FIGS.
4 will be described.

In this embodiment, an example of a reversal developing apparatus for developing a negative (negative) latent image on a photoreceptor using a negative (negative) toner will be described.

FIG. 2 is a schematic explanatory view of a cross section of a laser beam printer applied to the present invention.

OPC photosensitive drum 10 (diameter 24 mm)
Rotates in the direction of the arrow, and is uniformly charged by the charging roll 11 so that the dark portion potential (Vd) becomes −600 V.
Next, the image portion is exposed by the exposure device 14, and an electrostatic latent image having a bright portion potential (V1) of -150V is formed. A gap (300 μm) is set without contact between the photosensitive drum 10 and the developer layer on the developer carrier 16 (including the magnet 17), and an AC bias (f = 1800 Hz, Vpp = 1200)
V) and a DC bias (Vdc = −400 V) were applied to the developer carrier 16 by the bias applying means V, and the image portion was developed with negative toner to form a toner image on the photosensitive drum. Transfer the obtained toner image to a transfer roll 1
The toner is transferred onto the transfer material by 9 and the toner remaining on the surface of the photoconductor is cleaned by the cleaner 13. On the other hand, the transfer material P separated from the photosensitive drum 10 is heated and fixed by the heat fixing device H in order to fix the toner image on the transfer material P. Image formation is performed by repeating the above steps. At this time, the surface temperature of the temperature measuring element 21d of the heating body 21 of the heating and fixing apparatus H is 130 ° C., the total pressure between the heating body 21 and the pressure roller 23 is 6 kg, and the nip between the pressure roller and the film is 3 mm. Film 22
A heat-resistant polyimide film having a thickness of 50 μm and having a low-resistance release layer in which a conductive material is dispersed in PTEF on a contact surface with a transfer material was used.

When a non-magnetic toner is used, a sponge-made developer application roller is attached to the back surface of the developer carrier 16 in the developer container 15 to form an image.

Under the above set conditions, room temperature and normal humidity (25 ° C., 6
0% Rh) and a high temperature and high humidity (30 ° C., 80% Rh) environment at a printout speed of 4 sheets (A4 size) / min while replenishing the toner according to the present invention and the comparative toner. A printout test was performed on 10,000 continuous sheets, and the obtained images were evaluated for the following items. At the same time, matching between the used image forming apparatus and the toner was also evaluated.

[Evaluation of Printout Image] (1) Image Density The image density was evaluated by maintaining the image density at the end of printing out 3,000 sheets of ordinary paper for copying machines (75 g / m ² ).
The image density was measured by using a "Macbeth reflection densitometer" (manufactured by Macbeth Co., Ltd.) with respect to a printout image of a white background portion having a document density of 0.00.

◎ (excellent): 1.40 or more, ○ (good): 1.35 or more, and less than 1.40 Δ (acceptable): 1.00 or more, less than 1.35, × (impossible): 1.00 Less than

(2) Dot Reproducibility The pattern shown in FIG. 5 was printed out, and the dot reproducibility was evaluated.

: Very good (2 or less defects / 100) ○: Good (3 to 5/100 defects) Δ: Practical (6 to 10/100 defects) ×: Not practical (Lack 11 or more / 100)

(3) Image fog The fog density (%) was calculated from the difference between the whiteness of the white portion of the printout image measured by the “Reflectometer” (manufactured by Tokyo Denshoku Co., Ltd.) and the whiteness of the transfer paper. Image fog was evaluated.

◎: Very good (less than 1.5%) ：: Good (1.5% or more, less than 2.5%) Δ: Practical (2.5% or more, less than 4.0%) ×: Not practical (more than 4%)

(4) Fixing Property The fixing property was evaluated by applying a load of 50 g / cm ² , rubbing the fixed image with soft thin paper, and decreasing the image density before and after rubbing (%).

◎ (excellent): 5% or less, ○ (good): 5% or less, less than 10% Δ (acceptable): 10% or more, less than 20%, × (impossible): 20% or more

(5) Offset Resistance The offset resistance was evaluated by printing out a sample image having an image area ratio of about 5% and examining the degree of stain on the image after 3000 sheets.

◎: very good (not generated), ：: good (almost no occurrence) Δ: practical, ×: impractical

[Evaluation of Storage Stability] After the toner was left in a dryer set at 45 ° C. for one week,
A printout test was similarly performed on the left toner in a normal temperature and normal humidity environment, and the obtained image was evaluated from the image density and image quality.

[Evaluation of Matching of Image Forming Apparatus] (1) Matching with Developing Sleeve After completion of the printout test, the state of fixation of the residual toner on the surface of the developing sleeve and the influence on the printout image were visually evaluated.

◎: very good (not generated) ：: good (almost no occurrence) Δ: practical (there is sticking, but little influence on the image), ×: impractical (many sticking, image unevenness) Produces

(2) Matching with Photosensitive Drum The occurrence of scratches on the photoreceptor drum surface and adhesion of residual toner and the effect on printout images were visually evaluated.

◎: very good (not generated) ：: good (slight flaws are seen, but there is no effect on the image) Δ: practical (there is sticking or flaws, but the effect on the image is poor) (Small), ×: impractical (many sticks, causing vertical streak-like image defects)

(3) Matching with Fixing Apparatus The appearance of the fixing film surface was observed and its durability was evaluated.

(1) Surface Properties The state of occurrence of scratches and abrasion on the surface of the fixing film after completion of the printout test was visually evaluated.

◎: very good (not generated), ：: good (almost no occurrence) Δ: practical, ×: impractical

(2) Fixing State of Residual Toner The fixing state of the residual toner on the surface of the fixing film after completion of the printout test was visually evaluated.

◎: very good (not generated), ：: good (almost no occurrence) Δ: practical, ×: impractical

Tables 4 and 5 summarize the above evaluation results.

[0266]

[Table 4]

[0267]

[Table 5]

[0268]

As described above, according to the present invention,
By adjusting the amount of volatile components in the toner composition and specifying the physical properties of each component constituting the toner composition, it has an extremely wide fixable temperature range and excellent dot reproducibility. Thus, a stable and good toner image without fog could be formed for a long period of time.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram for explaining an image forming method according to the present invention.

FIG. 2 is a schematic explanatory view of an image forming apparatus used in an embodiment of the present invention.

FIG. 3 is an exploded perspective view of a main part of the fixing device used in the embodiment of the present invention.

FIG. 4 is an enlarged cross-sectional view of a main part showing a film state when the fixing device used in the embodiment of the present invention is not driven.

FIG. 5 is an explanatory diagram of a checker pattern for checking development characteristics of toner.

[Explanation of symbols]

 Reference Signs List 10 electrostatic latent image carrier (photosensitive drum) 11 charging means (charging roll) 12 cartridge 13 cleaning means 14 exposure means (image exposure) 15 developer container 16 developer carrier (developing means) 17 magnetic field generating means 18 elasticity Layer thickness regulating member 19 Transfer means (transfer roll) 20 Stay 21 Heating body 21a Heater substrate 21b Heating body 21c Surface protective layer 21d Temperature sensing element 22 Fixing film 23 Pressure roller 24 Coil spring 25 Film end regulating flange 26 Power supply connector 27 Disconnect Electrical member 28 Inlet guide 29 Outlet guide (separation guide) 30 Static elimination exposure

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Toyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-5-249734 (JP, A) JP-A-6 -118699 (JP, A) JP-A-6-67454 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9/08

Claims (16)

(57) [Claims] 1. A toner formed from a composition in which at least a binder resin, a colorant and a wax component are dispersed, wherein (a) the volatile component in the toner is less than 0.1% by weight, and (b) The wax component i) shows a maximum endothermic peak in a range of 70 to 130 ° C. in a DSC curve measured by a differential scanning calorimeter when the temperature is raised, and ii) ± 9 ° C. with respect to the peak temperature of the maximum endothermic peak. range and have a maximum exothermic peak at the time of temperature drop in, iii) the following general formula R-Y [wherein, R represents a hydrocarbon group, Y represents a hydroxyl group, a carboxyl group, alkyl ether group, an ester group, or Shows a sulfonyl group. Weight average molecular weight by GPC having
There toner for developing electrostatic images which is characterized that you containing 3,000 compounds 60 wt% or more. 2. In a molecular weight distribution of gel permeation chromatography (GPC) of tetrahydrofuran (THF) soluble portion of a binder resin in the toner, the toner has a main peak in a molecular weight region of 2,000 to 30,000, and,
2. The electrostatic image developing toner according to claim 1, wherein the toner has a subpeak or a shoulder in a region having a molecular weight exceeding 100,000. 3. The binder resin in the toner contains a THF insoluble matter.
Is 5% by weight or less, and the GPC
In the molecular weight distribution, the area ratio of the low molecular weight component having a molecular weight of 1,000 or less is 15% or less, and the area ratio of the high molecular weight component having a molecular weight of 1,000,000 or more is 0.5 to 2
The electrostatic image developing toner according to claim 1, wherein the toner content is 5%. 4. A high molecular weight component corresponding to a region having a molecular weight of 100,000 or more in a THF-soluble portion of a THF-soluble portion of a binder resin in the toner contains a polyfunctional polymerization initiator and / or a polyfunctional polymer. 4. The toner for developing an electrostatic image according to claim 1, wherein the toner is a polymer component obtained by using an unsaturated monomer. 5. A binder resin containing 0.1 to 0.3% by weight of a volatile component is prepared, and then at least a colorant and 70 to 70% at the time of temperature rise in a DSC curve measured by a differential scanning calorimeter. After mixing a wax component having a maximum endothermic peak in the region of 130 ° C. and having a maximum exothermic peak at a temperature fall of ± 9 ° C. with respect to the peak temperature of the maximum endothermic peak, 0.1% by weight of the volatile component %, Which comprises a step of melt-kneading until the amount becomes less than 0.1%. 6. The molecular weight of the binder resin obtained by using a polyfunctional polymerization initiator and / or a polyfunctional unsaturated monomer.
The method for producing a toner according to claim 5 , wherein the toner contains at least 100,000 high molecular weight polymers. 7. the wax component in the following general formula R-Y [wherein, R is a hydrocarbon group indicates, Y represents a hydroxyl group, a carboxyl group, alkyl ether group, an ester group, or a sulfo <br/> sulfonyl Represents a group. The method for producing a toner according to claim 5, wherein a compound having a weight average molecular weight by GPC of not more than 3,000 is not less than 60% by weight. 8. A charging step of applying a voltage to a charging member from the outside to charge a member to be charged, a step of forming an electrostatic image on the member to be charged, and developing the electrostatic image with toner. Developing a toner image on the transfer member by applying a voltage from the outside to the transfer member to transfer the toner image onto the transfer member; a fixing process of heating and fixing the toner image on the recording material; A cleaning step of cleaning the surface of the charged body with a cleaning member, wherein the toner is formed of a composition in which at least a binder resin, a colorant, and a wax component are dispersed; The volatile component in the toner is less than 0.1% by weight; (b) the wax is i) a DSC curve measured by a differential scanning calorimeter; Shown, ii) outermost and have a maximum exothermic peak at the time of cooling in the range of ± 9 ° C. for a large endothermic peak of the peak temperature, iii) in the following general formula R-Y [wherein, R is a hydrocarbon group And Y represents a hydroxyl group,
Boxy group, alkyl ether group, ester group or sulfo
Represents a nyl group. The weight average molecular weight by GPC with a '
There imaging method characterized that you containing 3,000 compounds 60 wt% or more. 9. The binder resin in the toner according to claim 1, wherein
Gel permeation chromatography of orchid (THF) soluble
Molecular weight distribution in the molecular weight distribution of GPC
It has a main peak in the region of 2,000 to 30,000, and
Subpeak or shoulder in the region of molecular weight over 100,000
9. An image forming apparatus according to claim 8, wherein
Method. 10. The binder resin in the toner is insoluble in THF.
Content is 5% by weight or less, and the THF-soluble
In the molecular weight distribution of C, the molecular weight is 1,000 or less.
The area ratio of the low molecular weight component is 15% or less, and
The area ratio of the high molecular weight component showing the amount of 1,000,000 or more is 0.5 to
It is 25%, The claim of Claim 8 or 9 characterized by the above-mentioned.
Image forming method. 11. The THF-soluble matter of the binder resin in the toner.
In the GPC molecular weight distribution of
The high molecular weight component corresponding to the region is a polyfunctional polymerization initiator and
And / or polymers obtained using polyfunctional unsaturated monomers
11. The composition according to claim 8, which is a component.
An image forming method according to any one of the above. 12. heating fixing process, there is no supply of the liquid for preventing the offset, or by not having heat fixing device fuser cleaner, claim, characterized in that for heating and fixing a toner image on a recording material 8 12. The image forming method according to any one of claims 1 to 11 . 13. The recording medium according to claim 13, wherein the heating and fixing step comprises the steps of: fixing the toner image to the recording material by using a fixedly supported heating member and a pressing member which is in pressure contact with the heating member and closely adheres to the heating member via a film. claim, characterized in that heating fixing 8 to 1
2. The image forming method according to any one of 1 . 14. the charging step, a charging member in contact with the member to be charged, a voltage is applied to from the charging member outside claims 8 to 13 noise, characterized in that for charging the member to be charged
An image forming method according to any one of the preceding claims. 15. A step of developing an electrostatic latent image on an electrostatic latent image carrier with a developer and electrostatically transferring the developed image to a transfer material via a transfer device, 15. The carrier according to claim 8, wherein the carrier and the transfer device are in contact with each other.
An image forming method according to any one of the preceding claims. 16. A coating layer containing conductive fine particles is formed on the surface of a developer carrying member that carries a toner on the surface and transports the toner to a developing area formed between the electrostatic latent image carrying member and the toner. 2. A developing device according to claim 1, wherein
5. The image forming method according to any one of 5 .