JPH07152217A - Full color image forming method - Google Patents

Abstract

PURPOSE:To provide a full color image forming method by which toner is prevented from being welded and stuck to a photoreceptor and an intermediate transfer body and an image is efficiently transferred even to a small-sized transfer material. CONSTITUTION:A toner image is formed on a photoreceptor 1 where a compound having fluorine and/or silicon atoms measured by X-ray photoelectron spectroscopy for chemical analysis exists on the surface layer of the photoreceptor having a laminated structure consisting of a charge generating layer and a charge transporting layer on a conductive supporting body and the ratio of the atoms to a carbon atom shows F/C=0.03 to 1.00 and Si/C=0.03 to 1.00 with toner particles in which SF-1 measured by Luzex is 100 to 110 and 5 to 30wt.% low softening point substance is contained. The toner image on the photoreceptor is transferred on the intermediate transfer body 5, a transfer roller 7 is brought into contact with a transfer material 6, and the toner image on the intermediate transfer body is transferred to the transfer material, then the toner image on the transfer material is thermally fixed on the transfer material by a heating means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method for forming a multicolor image using an intermediate transfer member utilizing electrophotography. That is, the present invention is an image forming method in which a toner image is previously formed on an electrostatic latent image bearing member (photoreceptor), and then the toner image is further transferred onto an intermediate transfer member and then collectively transferred onto a transfer material. The present invention relates to a full-color image forming method used for image forming in copiers, printers, fax machines and the like.

[0002]

2. Description of the Related Art Conventionally, in a full-color copying machine, 4
After developing the electrostatic latent image formed on each photoconductor using three photoconductors and belt-shaped transfer bodies with cyan, magenta, yellow, and black toners, the transfer material is conveyed between the photoconductor and the belt transfer body to be straight. After transferring between passes, the result is obtained by winding the transfer material by a method of forming a full-color image or the surface of the transfer body facing the photoconductor by electrostatic force or mechanical action such as a gripper, and performing the development-transfer process four times. A method for obtaining a full-color image is generally used.

In recent years, ordinary paper or film for overhead projector (OH) has been used as a transfer material for full color.
In addition to P), there is an increasing need to develop various materials such as cardboard, cards, and small size paper such as postcards. In the method using the above-described four photoconductors, the transfer material is conveyed straight, so that the range of application to various transfer materials is wide, but it is necessary to accurately superpose a plurality of toner images on a predetermined transfer material position. However, there is a problem in that it is difficult to obtain a high-quality image with good reproducibility due to a slight difference in registration, and the transfer material transport mechanism becomes complicated, leading to an increase in reliability and the number of parts. Also, when thick paper having a large basis weight is used in a method of adsorbing and winding the transfer material on the surface of the transfer body, the rear end of the transfer material causes poor adhesion due to the rigidity of the transfer material, resulting in transfer Image defects occur, which is not preferable. Image defects may also occur on small size paper.

A full-color image device using a drum-shaped intermediate transfer member is already known from US Pat. No. 5,187,526 and Japanese Patent Laid-Open No. 4-16426.
In US Pat. No. 5,187,526, the intermediate transfer roller having a surface layer made of polyurethane as a base material has a volume resistivity value of less than 10 ⁹ Ω · cm and is composed of the same surface layer. It is described that high image quality can be obtained when the volume resistivity of the transfer roller is 10 ¹⁰ Ω · cm or more. However, in such a system, a high output electric field is required in order to give a sufficient transfer charge amount to the toner at the time of transferring the toner to the transfer material. Therefore, it is composed of polyurethane in which the conductivity-imparting material is dispersed. The surface layer thus formed locally breaks down, and a noticeable image disturbance occurs in a halftone image with a small amount of toner, which is not preferable. Further, such high voltage application tends to cause transfer failure due to leakage of transfer current as the resistance of the transfer material decreases in an environment of high humidity where the relative humidity exceeds 60% RH. 40%
Even in a low-humidity environment of RH or less, transfer defects may occur due to uneven resistance unevenness of the transfer material.

Japanese Patent Application Laid-Open No. 59-15739 and Japanese Patent Application Laid-Open No. 59-5046 describe the relationship between the structure using an intermediate transfer member and the toner. However, in this publication, an adhesive intermediate transfer member is used.
It is only mentioned that toner of 0 μm or less can be efficiently transferred. Usually, in a system using an intermediate transfer member, it is necessary to once transfer the toner color image from the photosensitive member to the intermediate transfer member, and then transfer it again from the intermediate transfer member onto the transfer material. It is necessary to improve the transfer efficiency of toner as compared with. In particular, when a full-color copying machine that transfers a toner image after development is used, the amount of toner on the intermediate transfer body increases compared to the case of one color black toner used in a black-and-white copying machine, and the conventional toner is simply used. When used, it is difficult to improve the transfer efficiency. Furthermore,
When a normal toner is used, the surface of the photosensitive member or the intermediate member may be damaged due to a sliding force or a rubbing force between the photosensitive member or the intermediate transfer member and the cleaning member and / or between the photosensitive member and the intermediate transfer member. Toner fusion or filming may occur on the surface of the transfer member to deteriorate the transfer efficiency. In full color, the toner images of four colors may not be transferred uniformly, which may cause problems in color unevenness and color balance. It was difficult to stably output a high-quality full-color image.

Further, as the toner to be mounted on a normal full-color copying machine, it is necessary that the color toners are sufficiently mixed in the fixing step, and therefore the color reproducibility is improved and the O
The transparency of the HP image is important, and it is generally preferable to use a resin having a sharp melt and a low molecular weight for the color toner as compared with the black toner. Also, for normal black toner,
In order to improve the high-humidity offset property at the time of fixing, a releasing agent having a relatively high crystallinity such as polyethylene wax or polypropylene wax is used. However, in a full-color toner, the transparency of the OHP toner image is significantly impaired due to the crystallinity of the release agent. Therefore, normally, a high temperature offset property is improved by uniformly applying silicone oil or the like to a heat fixing roller without adding a release agent as a color toner constituent. However, since the transfer material having the toner-fixed image thus obtained has extra silicone oil or the like adhered to the surface thereof, it is not preferable because it causes discomfort when used by the user. In this way, for full-color image formation using an intermediate transfer member with many contact parts,
Currently there are many difficult problems. JP-A-59-15739 and JP-A-59-5046 do not propose any measures for the toner or the intermediate transfer member in this respect.

In recent years, as an electrophotographic photoreceptor, excellent sensitivity and electrical characteristics of the photoreceptor corresponding to the electrophotographic process,
Furthermore, optical characteristics are required. However, the contamination of the photoreceptor surface by nitrogen oxides generated by discharge in paper dust or air during normal repeated use, and the deterioration of the resin on the photoreceptor surface due to ozone, moisture, etc.
In particular, the charge retention power decreases under high humidity, which causes a reduction in resolution and image deletion. Since the surface of the photoconductor is coated with a resin, a lot of studies have recently been made on a polycarbonate resin having a skeleton of bisphenol A, which has excellent durability.

However, the polycarbonate resin is
Usually, the surface free energy is large and it is easily compatible with the resin used for the toner, and the toner is fused to the surface of the photoconductor, and in the case of reversal development on the image, white spotted image defects appear. Also, in the process of manufacturing the photoreceptor, after applying a charge transport material together with a polycarbonate resin onto a conductive support using a solvent, it is dried to form a coating film, but this coating film tends to have internal strain remaining, As a result, stress relaxation may appear as a crack during long-term storage, and a defect corresponding to the crack may appear on the image. Furthermore, the friction coefficient is high, and the surface layer of the photoreceptor is scraped off by polyurethane, polyester resin or the like as the blade material, which shortens the durable life, which is not preferable. Particularly in a system using an intermediate transfer body, it is most important to maintain high transfer efficiency, and a photoreceptor having less surface contamination is one of the points for using the intermediate transfer body.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming method which solves the above problems.

That is, an object of the present invention is to provide a full-color image forming method in which toner fusion and filming do not occur on the photosensitive member and the intermediate transfer member.

Another object of the present invention is to provide a full-color image forming method capable of excellently transferring to small size transfer materials such as cardboard, cards and postcards.

Another object of the present invention is to provide a full-color image forming method excellent in transfer efficiency.

Another object of the present invention is to provide a full-color image forming method having a low temperature fixing property in which a plurality of toners are sufficiently mixed.

It is another object of the present invention to provide a full-color image forming method for obtaining a color OHP image having excellent transparency.

[0015]

According to the present invention, an XPS (XPS (X) is used for the outer surface layer of a photoreceptor having a laminated structure of at least a charge generation layer and a charge transport layer on a conductive support.
A compound having fluorine and / or a silicon atom is present and the ratio with the carbon atom is F / C = 0.03 to 1.00 Si / C = 0.03 to 1. No. 00 on the photoconductor, a toner image was formed with toner particles having SF-1 measured by Luzex of 100 to 110 and a low softening point substance of 5 to 30% by weight. The toner image is transferred to the intermediate transfer member, the transfer roller is brought into contact with the transfer material, the toner image on the intermediate transfer member is transferred to the transfer material, and the toner image on the transfer material is transferred to the transfer material by heating means. The present invention relates to a full-color image forming method, characterized in that the toner is fixed by heating.

As the intermediate transfer member and the transfer roller used in the present invention, a general material for forming the transfer roller is used. In the present invention, the material of the transfer roller is more preferable than the volume resistivity value of the intermediate transfer member. By setting the volume resistivity value to be small, the voltage applied to the transfer roller can be reduced, a good toner image can be formed on the transfer material, and the transfer material can be prevented from being wound around the intermediate transfer body. Particularly, it is particularly preferable that the volume specific resistance value of the intermediate transfer member is 10 times or more than the volume specific resistance value of the transfer roller.

The hardness of the intermediate transfer member and the transfer roller is J
It is measured according to IS K-6301. The hardness of the intermediate transfer body used in the present invention is preferably composed of an elastic layer belonging to the range of 10 to 40 degrees, while the transfer roller hardness is harder than the hardness of the intermediate transfer body and has a value of 41 to 80 degrees. It is preferable to have the following in order to prevent the transfer material from winding around the intermediate transfer member. When the hardness of the intermediate transfer body and the hardness of the transfer roller are opposite, a recess is formed on the side of the intermediate transfer body, and winding of the transfer material around the intermediate transfer body occurs, which is not preferable.

The toner used in the present invention has a shape factor SF-1 value of 10 measured by Luzex.
A toner having a content of 0 to 110 and a low softening point substance of 5 to 30% by weight is preferably used.

SF-indicating the shape factor used in the present invention
1 means 100 toner images were randomly sampled using Hitachi FE-SEM (S-800), and the image information was introduced into Nicole image analyzer (Luxex3) through an interface for analysis. The value obtained by performing the calculation by the following equation was defined as the shape factor SF-1 in the present invention.

[0020]

[Equation 1]

[In the formula, MXLNG indicates an absolute maximum length,
AREA indicates the projected area of the toner. ]

A toner shape having a toner shape factor SF-1 larger than 110 gradually approaches an irregular shape from a spherical shape, and at the same time, a decrease in transfer efficiency is recognized. In the present invention, an intermediate transfer member is provided in order to deal with various materials, and the transfer step is performed substantially twice, so that the transfer efficiency is remarkably reduced and the toner utilization efficiency is reduced, which is a problem. Furthermore, in recent digital full-color copying machines and printers, color image originals are pre-printed in B (blue),
After color separation using G (green) and R (red) filters, a dot latent image of 20 to 70 μm is formed on the photoconductor and Y (yellow), M (magenta), C (cyan), B
It is necessary to reproduce a multicolor image faithful to the original by using the subtractive color mixing action using each color toner of (black). At this time, the Y, M, and
Since the C and B toners are loaded with a large amount of toner corresponding to the color information of the original or the CRT, each color toner used in the present invention is required to have an extremely high transfer property. A substantially spherical toner having a shape factor SF-1 of 100 to 110 is preferable.

To further improve the image quality, in order to faithfully develop smaller latent image dots, the toner also has a smaller particle size,
Specifically, a toner having a weight average particle diameter measured by a Coulter counter of 4 μm to 8 μm and a number variation coefficient of 35% or less is most preferable as the toner used in the present invention.
In the case of the toner having a weight average particle diameter of less than 4 μm, a large amount of transfer residual toner is generated on the photosensitive member or the intermediate transfer member due to poor transfer efficiency, which causes unevenness in the image due to fog and transfer failure. It is not preferable as a toner to be used. Further, when the weight average diameter of the toner exceeds 8 μm, fusion to the member is likely to occur, and when the number variation coefficient of the toner exceeds 35%, this tendency becomes more serious and becomes a problem.

The low softening point substance used in the present invention is preferably a compound having a main component maximum peak value measured according to ASTM D3418-8 of 40 to 90 ° C. If the maximum peak is less than 40 ° C., the self-aggregating force of the low softening point substance is weakened, and as a result, the high temperature offset property is weakened, which is not preferable for a full color toner. On the other hand, when the maximum peak exceeds 90 ° C., the fixing temperature becomes high, and it becomes difficult to appropriately smooth the surface of the fixed image, which is not preferable in terms of color mixing. Furthermore, when a toner is obtained by a direct polymerization method, since the granulation and polymerization are carried out in an aqueous system, when the temperature of the maximum peak value is high, a low softening point substance mainly precipitates during granulation and inhibits the suspension system. Therefore, it is not preferable.

In measuring the temperature of the maximum peak value of the present invention,
For example, Perkin Elmer DSC-7 is used. The melting point of indium and zinc is used to correct the temperature of the device detection unit, and the heat of fusion of indium is used to correct the amount of heat. An aluminum pan was used as a sample and an empty pan was set as a control, and the temperature rising rate was 10 ° C./min. Measure with.

Specifically, paraffin wax, polyolefin wax, Fischer-Tropsch wax,
Amide wax, higher fatty acid, ester wax and their derivatives or their graft / block compounds can be used. An ester wax having one or more long-chain ester moieties having 10 or more carbon atoms represented by the following general structural formula is particularly preferred in the present invention because it has an effect on high-temperature offset property without impairing transparency of OHP. . The structural formulas of typical compounds of specific ester waxes preferable in the present invention are shown below as general structural formulas, general structural formulas and general structural formulas.

[0027]

[Chemical 1]

[Wherein a and b represent an integer of 0 to 4,
a + b is 4, R ₁ and R ₂ represent an organic group having 1 to 40 carbon atoms, and a group having a carbon number difference between R ₁ and R ₂ of 10 or more, and n and m are 0 to 0. Indicates an integer of 15, n and m
Cannot be 0 at the same time. ]

[0029]

[Chemical 2]

[In the formula, a and b represent an integer of 0 to 4,
a + b is 4, R ₁ represents an organic group having 1 to 40 carbon atoms, n and m represent integers of 0 to 15, and n and m do not become 0 at the same time. ]

[0031]

[Chemical 3]

[Wherein a and b represent an integer of 0 to 3,
a + b is 3 or less, and R ₁ and R ₂ have 1 to 40 carbon atoms
And an organic group having a carbon number difference of 10 or more between R ₁ and R ₂ , R ₃ is an organic group having 1 or more carbon atoms, and n and m are integers from 0 to 15. As shown, n and m are never 0 at the same time. ]

The ester wax preferably used in the present invention preferably has a hardness of 0.5 to 5.0.
The hardness of the ester wax is 20 mmφ in diameter and 5 in thickness.
It is a value obtained by measuring Vickers hardness using a dynamic ultra-micro hardness meter (DUH-200) manufactured by Shimadzu Corporation after producing a cylindrical sample having a size of mm. The measurement condition is 0.5
10μ under the condition that the load speed is 9.67 mm / sec with a load of g
After displacing by m, it is held for 15 seconds, and the obtained dent shape is measured to obtain the Vickers hardness. The hardness of the ester wax preferably used in the present invention has a value of 0.5 to 5.0. A substance having a low softening point with a hardness of less than 0.5 increases pressure dependency and process speed dependency of the fixing device, and the high temperature offset effect is apt to be insufficiently expressed. Poor sex,
Similarly, the high-temperature offset tends to be insufficient because the release agent itself has a small self-cohesive force. Specific compounds include the following compounds.

[0034]

[Chemical 4]

In recent years, the need for full-color double-sided images has been increasing, and when forming a double-sided image, the fixing device is used even when the toner image on the transfer paper formed first on the front surface forms the image on the rear surface next. There is a possibility that the toner may pass through the heating section of No. 2 again, and it is necessary to more fully consider the high temperature offset property of the toner. Therefore, in the present invention, it is essential to add a large amount of the low softening point substance. Specifically, the low softening point substance is preferably added to the toner in an amount of 5 to 30% by weight. If it is added in an amount of less than 5% by weight, sufficient high-temperature offset property is not exhibited, and further, the image on the back side tends to show an offset phenomenon when fixing a double-sided image. On the other hand, if it exceeds 30% by weight, during the production of the toner, for example, in the production by the pulverization method, the device fusion or the toner fusion tends to occur,
Even in the production by the polymerization method, toner particles are likely to coalesce with each other during granulation, and particles having a wide particle size distribution are likely to be produced, which is not suitable for the present invention.

The method for producing the toner of the present invention includes:
Resin, mold release agent consisting of low softening point material, colorant, charge control agent, etc. are evenly dispersed using a pressure kneader, extruder or media disperser, and then mechanically or in a jet stream collide with the target. In addition to a so-called pulverization method for producing a toner by finely pulverizing the toner to a desired toner particle size and then further sharpening the particle size distribution through a classification step, there is a method disclosed in Japanese Patent Publication No. 56-13945. And a method for atomizing a molten mixture into the air using a disk or a multi-fluid nozzle described in JP-A-36-10.
No. 231, JP-A-59-53856, and JP-A-59-61842, a method of directly producing a toner using a suspension polymerization method, or a method in which a toner is soluble in a monomer is obtained. The polymer used is a dispersion polymerization method in which a toner is directly produced using an insoluble aqueous organic solvent, or an emulsion polymerization method typified by a soap-free polymerization method in which a toner is produced by direct polymerization in the presence of a water-soluble polar polymerization initiator. It is possible to produce toner.

However, in the method of producing a toner using the pulverization method, it is difficult to set SF-1 which is the shape factor of the toner measured by Luzex within the range of 100 to 110, and in the melt spray method, SF
Even if the -1 value can be set within a predetermined range, the particle size distribution of the obtained toner tends to be wide, and the manufacturing method is low in efficiency. On the other hand, in the dispersion polymerization method, the obtained toner shows an extremely sharp particle size distribution, but the selection of materials to be used is narrow and the use of organic solvents is not suitable for production equipment from the viewpoint of waste solvent treatment and solvent flammability. It is complicated and easily complicated. The emulsion polymerization method represented by soap-free polymerization is effective because the particle size distribution of the toner is relatively uniform,
When the used emulsifier or the end of the initiator is present on the surface of the toner particles, the environmental characteristics are easily deteriorated.

In the present invention, the toner shape factor SF-
The suspension polymerization method under atmospheric pressure or under pressure is particularly preferable because it can control the value of 100 to 110 and relatively easily obtains a fine particle toner having a particle size distribution of 4 to 8 μm with a sharp particle size distribution. A so-called seed polymerization method, in which a monomer is further adsorbed on the obtained polymer particles and then polymerized by using a polymerization initiator, can be suitably used in the present invention.

A more preferable toner used in the present invention is a toner shape factor SF-1 measured by Luzex.
Is 100 to 110 and the low softening point substance is 5 to 30.
The low softening point substance is contained by the direct polymerization method in which the outer shell resin layer is included by the method of measuring the tomographic plane of the toner using a transmission electron microscope (TEM).

From the viewpoint of fixability, it is necessary to include a large amount of the low softening point substance in the toner, so that it is necessary to encapsulate the low softening point substance in the outer shell resin. The toner that cannot be encapsulated cannot be sufficiently pulverized unless special freeze pulverization is used in the pulverization process, and as a result, only a wide particle size distribution can be obtained, and toner fusion to the device also occurs. It's very bad. Further, in freeze pulverization, the device becomes complicated due to measures for preventing dew condensation on the device, and if the toner absorbs moisture, the workability of the toner is deteriorated,
Further, it is necessary to add a drying step, which is a problem.
As a specific method for encapsulating the low softening point substance, the polarity of the material in the aqueous medium is set to be smaller for the low softening point substance than the main monomer, and a small amount of a resin or monomer having a large polarity is used. By adding the above, it is possible to obtain a toner having a so-called core-shell structure in which a substance having a low softening point is coated with an outer shell resin. Toner particle size distribution control and particle size control are carried out by changing the type and addition amount of sparingly water-soluble inorganic salt or dispersant that acts as a protective colloid, and mechanical device conditions such as rotor peripheral speed, number of passes, stirring. The toner of the present invention can be obtained by controlling the stirring conditions such as the blade shape, the container shape, or the solid content concentration in the aqueous solution.

As a specific method for measuring the tomographic plane of the toner in the present invention, a cured product obtained by sufficiently dispersing the toner in an epoxy resin which is curable at room temperature and then curing it in an atmosphere at a temperature of 40 ° C. for 2 days Was stained with ruthenium tetraoxide and, if necessary, osmium tetraoxide in combination, a thin sample was cut out using a microtome equipped with diamond teeth, and the toner morphology was measured using a transmission electron microscope (TEM). . In the present invention, it is preferable to use the ruthenium tetroxide dyeing method in order to make a contrast between the materials by utilizing a slight difference in crystallization between the low softening point substance used and the resin constituting the outer shell. A typical example is shown in FIG. It was clearly observed that the low softening point substance was encapsulated by the outer shell resin.

As the outer shell resin used in the present invention, generally used styrene- (meth) acrylic copolymers, polyester resins, epoxy resins and styrene-butadiene copolymers can be used. In the method of directly obtaining the toner by the polymerization method, those monomers are preferably used. Specifically, styrene, o (m-,
styrene-based monomers such as p-)-methylstyrene and m (p-)-ethylstyrene; methyl (meth) acrylate,
Ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, ( (Meth) acrylic acid ester-based monomers such as 2-ethylhexyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, and diethylaminoethyl (meth) acrylate; butadiene, isoprene, cyclohexene, (meth) acrylonitrile, acrylic acid An ene-based monomer such as amide is preferably used. These are alone or generally in the publication Polymer Handbook 2nd Edition III-P1.
39-192 (made by John Wiley & Sons)
The theoretical glass temperature (Tg) described in (4) is used by appropriately mixing the monomers so as to show 40 to 75 ° C. When the theoretical glass transition temperature is lower than 40 ° C., problems occur in terms of storage stability of the toner and durability stability of the developer. On the other hand, when it exceeds 75 ° C., the fixing point rises. In this case, the color mixing of the toners of respective colors is insufficient and the color reproducibility is poor, and the transparency of the OHP image is significantly reduced, which is not preferable in terms of high image quality. The molecular weight of the outer shell resin is measured by GPC (gel permeation chromatography). As a specific method for measuring GPC, the toner was previously extracted with a Soxhlet extractor in a toluene solvent for 20 hours, and then the toluene was distilled off with a rotary evaporator, and the low softening point substance was dissolved, but the outer shell resin was dissolved. Is an insoluble organic solvent such as chloroform, and after thorough washing, a solution soluble in THF (tetrahydrofuran) is filtered through a solvent-resistant membrane filter having a pore size of 0.3 μm to obtain a waters 150C sample. And the column configuration is Showa Denko A
-801, 802, 803, 804, 805, 806,
The molecular weight distribution can be measured by connecting 807 and using a calibration curve of a standard polystyrene resin. The number average molecular weight (Mn) of the obtained resin component is 5,000 to 1,000,000,
An outer shell resin having a ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of 2 to 100 is preferable for the present invention.

In the present invention, it is particularly preferable to add a polar resin in addition to the outer shell resin in order to encapsulate the low softening point substance in the outer shell resin. As the polar resin used in the present invention, a copolymer of styrene and (meth) acrylic acid, a maleic acid copolymer, a saturated polyester resin, and an epoxy resin are preferably used. It is particularly preferable that the polar resin does not contain an unsaturated group capable of reacting with the shell resin or the monomer in the molecule. In the case of containing a polar resin having an unsaturated group, a crosslinking reaction occurs with a monomer forming the outer shell resin layer, resulting in an extremely high molecular weight as a full-color toner, which is disadvantageous for color mixing of four-color toner, which is not preferable. .

As the colorant used in the present invention, carbon black, a magnetic substance, or a yellow / magenta / cyan colorant shown below, which is toned black, is used.

Examples of magenta colorants include condensed azo compounds, isoindolinone compounds, anthraquinone compounds,
Compounds represented by azo metal complexes, methine compounds and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 6
2, 74, 83, 93, 94, 95, 109, 110,
111, 128, 129, 147, 168 and the like are preferably used.

As the magenta colorant, a condensed azo compound, a diketopyrrolopyrrole compound, an anthraquinone, a quinacridone compound, a basic dye lake compound, a naphthol compound, a benzimidazolone compound, a thioindigo compound, and a perylene compound are used. Specifically, C.I.
I. Pigment Red 2, 3, 5, 6, 7, 23, 4
8; 2, 48; 3, 48; 4, 57; 1, 81; 1, 1
44, 146, 166, 169, 177, 184, 18
5,202,206,220,221,254 are particularly preferred.

As the cyan colorant, a copper phthalocyanine compound and its derivative, an anthraquinone compound, a basic dye lake compound and the like can be used. Specifically, C.I. I.
Pigment Blue 1, 7, 15, 15: 1, 15: 2,
15: 3, 15: 4, 60, 62, 66 and the like can be used particularly preferably.

These colorants may be used alone or in a mixture, and may be used in the form of a solid solution. The colorant of the present invention is selected in terms of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in the toner. The colorant is added in an amount of 1 to 20 parts by weight based on 100 parts by weight of the resin.

When a magnetic substance is used as the black colorant, unlike other colorants, it is 40 to 100 parts by weight of the resin.
It is used by adding 150 parts by weight.

The charge control agent used in the present invention includes
Known charge agents can be used, but a charge control agent that is colorless and has a high toner charging speed and that can stably maintain a constant charge amount is preferable. Further, when the direct polymerization method is used in the present invention, a charge control agent having no polymerization inhibitory property and having no solubilized product in an aqueous system is particularly preferable. Specific compounds include:
As a negative system, metal compounds of salicylic acid, naphthoic acid, dicarboxylic acid, sulfonic acid, polymer compounds having a carboxylic acid in the side chain, boron compounds, urea compounds, silicon compounds, currys arenes, etc. can be used. A quaternary ammonium salt, a polymer type compound having the quaternary ammonium salt in its side chain, a guanidine compound, an imidazole compound and the like are preferably used. The charge control agent is resin 10
0.5 to 10 parts by weight is preferable with respect to 0 parts by weight. However, the addition of the charge control agent is not essential in the present invention, and when the two-component developing method is used, the frictional charging with the carrier is used, and the blade is used even when the non-magnetic one-component blade coating developing method is used. By positively utilizing the triboelectric charging with the member or the sleeve member, it is not always necessary to include the charge control agent in the toner.

When the direct polymerization method is used in the present invention, as a polymerization initiator, for example, 2,2'-azobis-
(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2, Azo-based polymerization initiators such as 4-dimethylvaleronitrile and azobisisobutyronitrile; peroxide-based initiators such as benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide A polymerization initiator is used. Although the amount of the polymerization initiator added varies depending on the desired degree of polymerization, it is generally 0.
It is used by adding 5 to 20% by weight. Although the type of the polymerization initiator varies slightly depending on the polymerization method, it may be used alone or in combination with reference to the 10-hour half-life temperature.

It is also possible to further add and use a known crosslinking agent, chain transfer agent, polymerization inhibitor or the like in order to control the degree of polymerization.

When the suspension polymerization is used as the toner production method of the present invention, the dispersant used is, for example, an inorganic oxide such as tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, carbonic acid. Examples thereof include calcium, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina, magnetic materials and ferrite.
As the organic compound, for example, polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, starch and the like are used by dispersing in an aqueous phase. It is preferable to use 0.2 to 2.0 parts by weight of these dispersants with respect to 100 parts by weight of the polymerizable monomer.

As these dispersants, commercially available ones may be used as they are, but in order to obtain dispersed particles having a fine and uniform particle size, the inorganic compound may be formed in a dispersion medium under high speed stirring. I can. For example, in the case of tricalcium phosphate, a dispersant suitable for the suspension polymerization method can be obtained by mixing an aqueous sodium phosphate solution and an aqueous calcium chloride solution under high stirring. Further, 0.001 to 0.1 part by weight of a surfactant may be used in combination for making the dispersant fine. Specifically, commercially available nonionic, anionic, and cation type surfactants can be used. For example, sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate,
Sodium oleate, sodium laurate, potassium stearate, calcium oleate and the like are preferably used.

When the direct polymerization method is used in the toner manufacturing method of the present invention, the toner can be specifically manufactured by the following manufacturing method. That is, a releasing agent, a colorant, a charge control agent, a polymerization initiator and other additives made of a low softening point substance are added to a polymerizable monomer and uniformly dissolved or dispersed by a homogenizer or an ultrasonic disperser. The above monomer system is dispersed in an aqueous phase containing a dispersion stabilizer by a usual stirrer, homomixer, homogenizer or the like. Preferably, the stirring speed and time are adjusted so that the monomer droplets have the desired toner particle size, and granulation is performed. After that, stirring may be performed to the extent that the particle state is maintained and the particles are prevented from settling due to the action of the dispersion stabilizer. The polymerization temperature is 40 ° C. or higher, generally 50 to 9
It is preferable to carry out the polymerization by setting the temperature at 0 ° C. In addition, the temperature may be raised in the latter half of the polymerization reaction, and in the latter half of the reaction or the end of the reaction in order to remove unreacted polymerizable monomers and by-products that may cause odor during toner fixing. The aqueous medium may be partially distilled off later. After the reaction is completed, the produced toner particles are collected by washing and filtration and dried. In the suspension polymerization method, water is usually added in an amount of 300 to 100 parts by weight of the monomer system.
It is preferable to use 3000 parts by weight as the dispersion medium.

On the other hand, as the photoreceptor used in the image forming method of the present invention, particles of fluorine and / or silicon compound are dispersed in a polycarbonate resin in the outermost layer within about 90Å from the surface layer of the charge transport layer and / or the protective layer. By finely dispersing or solubilizing the particles to a diameter of 5.0 μm or less, it is possible to maintain high transfer efficiency of the toner from the photoconductor, and it is particularly preferable to use an intermediate transfer body.

When the toner of the present invention contains a large amount of the low-softening substance and the polar substance in the toner, the fixing property, for example, the color mixing property and the high temperature offset property becomes excellent, but Toner easily adheres to the toner, and when the transferability and the cleaning property are deteriorated, the toner may be fused to the photoreceptor.

The inventors of the present invention have studied to solve this problem. As a result, the surface layer of the electrophotographic photosensitive member has a ratio of fluorine and / or silicon atoms to carbon atoms of F / C = 0.03 to. It has been found that the presence of 1.00 and Si / C = 0.03 to 1.00 can solve the above problems satisfactorily.

The reason for defining F / C and Si / C here is that the compound containing F and Si atoms lowers the surface energy of the photoconductor and reduces the transferability and adhesion of the toner. On the other hand, the presence of carbon atoms increases the surface energy. The present inventors have found that by defining this ratio, the transferability is good even in the toner structure that easily adheres as in the present invention, and a cleaning failure does not occur.

When the F / C and Si / C of the surface layer of the photoconductor are less than 0.03 with respect to the toner of the present invention, the surface energy of the photoconductor is high and the transferability of the toner is deteriorated. On the other hand, F / C and Si / C are 1.00 respectively
If it exceeds, the coefficient of friction of the photosensitive member with the cleaning member decreases, and conversely, toner slips through and defective cleaning easily occurs.

A more preferable constitution is that the surface layer in the electrophotographic photosensitive member of the present invention contains a polycarbonate, and even more preferably, the polycarbonate is synthesized from an asymmetric diol. Due to this, it has excellent durability and good productivity,
It can be an electrophotographic photoreceptor. As a more preferable configuration, having a protective layer on the photosensitive layer in the electrophotographic photoreceptor,
In addition, it is preferable that the protective layer contains polycarbonate. This results in additional stability of durability characteristics. Specific examples of the fluorine compound include fluorine resin, tetrafluoroethylene, trifluoroethylene chloride, hexafluoropropylene,
One or a polymer of vinyl fluoride, vinylidene fluoride, ethylene difluoride dichloride and a copolymer thereof, or
More than that is appropriately selected. Also, carbon fluoride or the like can be used.

In the present invention, a block or graft polymer containing a fluorine-containing segment, which is synthesized by polymerization or copolymerization with a fluorine-based polymerizable monomer or a non-fluorine-based polymerizable monomer, a surfactant, a macromolecule. The monomers and the like can be used alone or in combination with the above-mentioned fluorine-based resin.

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

Preferred examples of the fluorine-based polymer monomer are shown below, but the compounds that can be used are not limited to the ranges given here.

[0065]

[Chemical 5]

(In the above compounds, R ₁ represents a hydrogen atom, a halogen atom or a methyl group, R ₂ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or a nitrile group, and a combination of several kinds thereof may be used. Is an integer of 1 to 4, m is an integer of 1 to 5, k + m = 5, and Rf
Represents an alkyl group substituted with at least one fluorine atom. )

Examples of the non-fluorine-based polymerizable monomer include low molecular weight linear unsaturated hydrocarbons, vinyl halides, vinyl esters of organic acids, vinyl aromatic compounds, acrylic acid and methacrylic acid esters, N-vinyl. One or more compounds such as compounds, vinyl silicon compounds, maleic anhydride, esters of maleic acid and fumaric acid can be used, and a charge transport layer to which the formed fluorine-based graft polymer is added and It is preferable to select one that is compatible with the resin layer of the protective layer, or that has a similar structure even if it is not completely compatible and that has a slight affinity between the two.

Specific examples of the silicon-based compound include a monomethylsiloxane three-dimensional crosslinked product, a dimethylsiloxane-monomethylsiloxane three-dimensional crosslinked product, an ultrahigh molecular weight polydimethylsiloxane, a block polymer containing a polydimethylsiloxane segment, a graft polymer, and an interface. Activators, macromonomers, end-modified polydimethylsiloxane, etc. are used. In the case of a three-dimensional crosslinked product, it is used in the form of fine particles and the like, and the particle size can be used in the range of 0.01 to 5 μ. In the case of a polydimethylsiloxane compound, its molecular weight can be used in the range of 3,000 to 5,000,000. The fine particles are dispersed as a photosensitive layer composition together with a binder resin. As a dispersing method, a sand mill, a ball mill, a roll mill, a homogenizer, a nanomizer, a paint shaker, an ultrasonic wave or the like is used. At the time of dispersion, it is preferable to use the above-mentioned graft, block polymer or surfactant as a dispersion aid, and it is also preferable to use them in combination for controlling the Si / C ratio which is a feature of the present invention.

Further, as a means for achieving the object of the present invention more effectively, it is preferable that the charge transport layer and / or the protective layer contain polycarbonate. The polycarbonate is preferably a polycarbonate synthesized using an asymmetric diol.

The polycarbonate of the present invention must be soluble in an aromatic hydrocarbon solvent or a halogenated aromatic hydrocarbon solvent, and sufficient solubility can be obtained by reducing the crystallinity of the polycarbonate. Specifically, for example, 1) bisphenol A and one or more asymmetric diol compounds 2) One or more asymmetric diol compounds can be obtained by a general polycarbonate synthesis method such as the phosgene method. it can. It can also be obtained by using a diol compound having a side chain with a substituent having 3 or more carbon atoms.

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

[0072]

[Chemical 6]

[0073]

[Chemical 7]

[0074]

[Chemical 8]

[0075]

[Chemical 9]

[0076]

[Chemical 10]

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

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

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

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

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

In the function-separated type photoreceptor, selenium-tellurium, pyrylium, thiapyrylium dyes, phthalocyanine pigments, anthanthrone pigments, dibenzpyrenequinone pigments, pyranthrone pigments, trisazo pigments, diazo pigments, azo pigments are used as charge generating substances. , Indigo pigment,
A quinacridone pigment, an asymmetric quinocyanine, a quinocyanine, or amorphous silicon described in JP-A-54-143645 can be used, and as the charge-transporting substance, pyrene, N-ethylcarbazole, N-
Isopropylcarbazole, N-methyl-N-phenylhydrazino-3-methylidene-9-ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-
9-ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-10-ethylphenothiazine,
N, N-diphenylhydrazino-3-methylidene-10
-Ethylphenoxazine, P-diethylaminobenzaldehyde-N, N-diphenylhydrazone, P-diethylaminobenzaldehyde-N-α-naphthyl-N-phenylhydrazone, P-pyrrolidinobenzaldehyde-
Hydrazones such as N, N-diphenylhydrazone, 1,3,3-tramethylindolenine-ω-aldehyde-N, N-diphenylhydrazone, P-diethylbenzaldehyde-3-methylbenzthiazolinone-2-hydrazone, 2,5-bis (P-diethylaminophenyl)-
1,3,4-oxadiazole, 1-phenyl-3-
(P-Diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, 1- [quinolyl (2)]
-3- (P-diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, 1 [pyridyl (2)]-3- (P-diertiaminostyryl) -5-
(P-diethylaminophenyl) pyrazoline, 1- [6
-Methoxy-pyridyl (2)]-3- (P-diethylaminostyryl) -5- (P-diethylaminophenyl)
Pyrazoline, 1- [pyridyl (3)]-3- (P-diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, 1- [lepidyl (2)]-3- (P
-Diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, 1- [pyridyl (2)]-3
-3 (P-diethylaminostyryl) -4-methyl-5
-(P-diethylaminophenyl) pyrazoline, 1-
[Pyridyl (2)]-3- (α-methyl-P-diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, 1-phenyl-3- (P-diethylaminostyryl) -4-methyl-5- ( P-Diethylaminophenyl) pyrazoline, 1-phenyl-3- (α-benzyl-P-diethylaminostyryl) -5- (P-diethylaminophenyl) pyrazoline, pyrazolines such as spiropyrazoline, 2- (P-diethylaminostyryl) -6 -Diethylaminobenzoxazole, 2-
Oxazole compounds such as (P-diethylaminophenyl) -4- (P-dimethylaminophenyl) -5- (2-chlorophenyl) oxazole, thiazole compounds such as 2- (P-diethylaminostyryl) -6-diethylaminobenzothiazole , Bis (4-diethylamino-2-methylphenyl) -phenylmethane and other triarylmethane compounds, 1,1-bis (4-N, N-diethylamino-2-methylphenyl) heptane, 1,1,
2,2-Tetrakis- (4-N, N-dimethylamino-
Polyarylalkanes such as 2-methylphenyl) ethane can be used.

The charge generation layer contains the charge generation material described above.
It is formed by well dispersing with a binder resin and a solvent in an amount of 3 to 4 times and a solvent by a method such as a homogenizer, ultrasonic wave, ball mill, vibrating ball mill, sand mill, attritor, or roll mill, and coating and drying. Its thickness is 0.1
It is about 1 μm.

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

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

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

[0087]

EXAMPLES The present invention will be described more specifically by showing examples below.

[Production Example 1 of Photoreceptor] 10 parts by weight of conductive titanium oxide (tin oxide coating, average primary particle size 0.4 μm), 10 parts by weight of phenol resin precursor (resole type),
After dispersing 10 parts by weight of methanol and 10 parts by weight of butanol in a sand mill, an outer diameter of 80 mm and a length of 360 mm
The aluminum cylinder was applied by dip coating and cured at 140 ° C., and then a conductive layer having a volume resistance of 5 × 10 ⁹ Ωcm and a thickness of 20 μm was provided.

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

[0090]

[Chemical 11]

[In the formula, m and n represent integers. ] And 150 parts by weight of isopropanol were mixed and dissolved, and then dip coated on the conductive layer to form an undercoat layer of 1 μm.

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

[0093]

[Chemical 12]

5 parts by weight of the following polycarbonate resin (bisphenol A type, molecular weight 30,000):

[0095]

[Chemical 13]

[In the formula, n represents an integer. ] And 700 parts by weight of cyclohexanone were dispersed by a sand mill, and the dispersion was dip-coated on the undercoat layer to obtain a charge generation layer of 0.05 μm.

Next, 10 parts by weight of the following triphenylamine,

[0098]

[Chemical 14]

10 parts by weight of a polycarbonate resin having the following structure (bisphenol Z type, molecular weight 20,000)

[0100]

[Chemical 15]

[In the formula, n represents an integer. 50 parts by weight of monochlorobenzene and 15 parts by weight of dichloromethane were mixed by stirring, and then dip-coated on the charge generation layer. The coated cylinder was dried with hot air to form a 20 μm charge transport layer.

Then, fine powder of carbon fluoride (average particle size of 0.
23 μm, made by Central Glass Co., Ltd. 1 part by weight, polycarbonate resin (bisphenol Z type, molecular weight 80,000)
0) 6 parts by weight, the following perfluoroalkyl acrylate-methyl methacrylate block copolymer (molecular weight 3
50,000) 0.1 parts by weight

[0103]

[Chemical 16]

[In the formula, n represents 4 to 16, and i and j represent integers. ] 120 parts by weight of monochlorobenzene and 80 parts by weight of dichloromethane were dispersed and mixed in a sand mill. To this, 3 parts by weight of triphenylamine was added, mixed and dissolved, and applied on the charge transport layer by spray coating,
A photoconductor drum was provided with a protective layer of 5 μm.

After the surface of the obtained photoconductor was peeled off, the surface analysis was measured by an ESCALAB200-X type X-ray photoelectron spectrometer manufactured by VG. MgCa (3 as X-ray source
00W) was used to measure the area of 2 × 3 mm.
The surface of the photoconductor of Production Example 1 had 5.2% F atoms and 8 C atoms.
It was 1.3% and the F / C ratio was 0.064.

[Production Example 2 of Photoreceptor] In the photoreceptor of Production Example 1, a photoconductor drum was produced by replacing the protective layer with the following formulation.

That is, three-dimensional spherical cross-linked polysiloxane fine particles (average particle diameter 0.29 μm, manufactured by Toshiba Silicone Co.) 1
Parts by weight, polycarbonate resin (bisphenol Z type,
Molecular weight 80,000) 6 parts by weight, the following polydimethylsiloxane methacrylate-methyl methacrylate block copolymer (molecular weight 50,000, Si amount 10 parts by weight)
0.1 parts by weight

[0108]

[Chemical 17]

[In the formula, n represents 1 to 15, and i and j represent integers. ] 120 parts by weight of monochlorobenzene and 80 parts by weight of dichloromethane were dispersed and mixed in a sand mill. To this, 3 parts by weight of triphenylamine was added, mixed and dissolved, and applied on the charge transport layer by spray coating,
A photoconductor drum was provided with a protective layer of 3 μm.

After peeling off the surface of the photoreceptor, E manufactured by VG
Surface analysis was performed with an X-ray photoelectron spectrometer manufactured by SCALAB200-X. Using MgCa (300 W) as an X-ray source, measurement was performed at a depth of several tens of liters in a region of 2 × 3 mm. The surface of the photoconductor of Production Example 2 has Si atoms of 10.2% and C
The number of atoms was 69.3%, and the Si / C ratio was 0.147.

Example 1 FIG. 1 is a sectional view of an image forming apparatus used in Example 1. As the photoconductor 1, the photoconductor manufactured by the photoconductor manufacturing example 1 is used, and the surface of the photoconductor is charged to a surface potential of about -600 V by the charging roller 2 which rotates in the direction of the arrow and rotates in a counter-contact manner. The exposure is turned on and off by a polygon mirror in accordance with digital image information on the photoconductor to form an electrostatic latent image with an exposed portion potential of -100V and a dark portion potential of -600V. Multiple developing devices 4-1, 4-2, 4-
Yellow, magenta, cyan, and black toners of Nos. 3, 4 and 4 were applied on the photoconductor by a reversal development method to obtain a color image. The color-developed image is transferred onto the intermediate transfer member for each color to form a four-color superposed color-developed image on the intermediate transfer member. The transfer residual toner on the photoconductor is collected in the residual toner container by the cleaner member.

Since the spherical toner naturally has a higher transfer efficiency than the irregular toner, a problem is less likely to occur even in a simple system without a bias roller or a cleaner member.
The intermediate transfer member consists of carbon black, zinc oxide,
A conductive layer made of tin oxide, silicon carbide or the like was sufficiently dispersed in nitrile-butadiene rubber (NBR) to coat an elastic layer. The hardness of the coating layer is JIS K-63.
According to 01, 35 degrees and volume resistivity value is 10 ⁹ Ω
・ It was cm. The required transfer current from the photosensitive member to the intermediate transfer member was about 5 μA, which was obtained by applying +500 V on the cored bar from the power supply. 20m transfer roller
The core metal of m was coated with a conductive material such as carbon, zinc oxide, tin oxide, or silicon carbide, which was sufficiently dispersed in a foam of ethylene-propylene-diene terpolymer (EPDM). The volume resistivity of the elastic layer is 1
0 ⁶ Ω · cm, JIS K-6301 standard hardness is 3
The one showing a value of 0 degree was used. For the contaminated toner on the transfer roller when the toner is collectively transferred from the intermediate transfer member to the transfer material, a fur brush cleaner or a cleaning member-less system is generally used as a cleaning member. By setting the ratio to 100 to 110, a cleaning member-less system could be adopted because of high transfer efficiency.

The cyan toner used in this example was prepared as follows. Into a 2-liter four-necked flask equipped with a high-speed stirring device TK-Homomixer, ion-exchanged water 71
0 parts by weight and 0.1 mol / liter-Na ₃ PO ₄ aqueous solution 4
Add 50 parts by weight and adjust the rotation speed to 12000 rotations,
It was heated to 65 ° C. 1.0 mol / liter-
68 parts by weight of an aqueous CaCl ₂ solution was gradually added to prepare a dispersion medium system containing a minute sparingly water-soluble dispersant Ca ₃ (PO ₄ ) ₂ . On the other hand, the dispersoid system is

Styrene monomer 165 parts by weight n-butyl acrylate monomer 35 parts by weight C.I. I. Pigment Blue 15: 314 14 parts by weight Saturated polyester 10 parts by weight (Terephthalic acid-propylene oxide modified bisphenol A acid value 15, peak molecular weight 6000) Metallic salicylate compound 2 parts by weight Compound (1) (maximum peak value 59.4 ° C., 60 Weight part Vickers hardness 1.5)

The above mixture was dispersed by using an attritor for 3 hours, and then 10 parts by weight of 2,2'-azobis (2,4-dimethylvaleronitrile) which was a polymerization initiator was added to the dispersion medium. Input 1 while maintaining the rotation speed
Granulated for 5 minutes. After that, the stirrer was changed from the high speed stirrer to the propeller stirrer and the internal temperature was raised to 80 ° C., and the polymerization was continued at 50 rpm for 10 hours. After the polymerization was completed, the slurry was cooled and diluted hydrochloric acid was added to remove the dispersant. The weight average diameter of the cyan toner measured by a Coulter counter by further washing and drying was 6.2 μm, the number variation coefficient was 27%, and SF-1 was 104. A schematic diagram of a tomographic photograph of the obtained cyan toner is shown in FIG. It shows a structure in which the compound (1) which is a low softening point substance is covered with an outer shell resin. 2% of hydrophobized titanium oxide was externally added to the obtained toner to obtain a toner having excellent fluidity.

For other yellow, magenta and black toners, the colorant is C.I. I. Pigment Yellow 17,
C. I. Pigment Red 202 and graft carbon black were used, and a polymerized toner having SF-1 of 101 to 105 was obtained by the same method. That is, yellow toner, magenta toner and black toner were obtained.

Using the above-mentioned image forming method, image formation was carried out with a two-component developer using the above-mentioned four color toners and a carrier, and fixing was carried out using a heat roller fixing device. As a result of image formation using a grammage of 199 g / m ² as a transfer material, a high-quality image having excellent color mixture and no voids was obtained. Further, double-sided images were formed, but no offset was observed on both the front and back surfaces of the transfer material. An endurance test was performed on 50,000 sheets, but there was no change in the image density between the initial stage and the endurance period, and no toner fusion to the member was observed.
At this time, the transfer efficiency from the photosensitive member to the intermediate transfer member was 98%, the transfer efficiency from the intermediate transfer member to the transfer material was 99%, and the total transfer efficiency was as high as 97.0%.

Example 2 Using the image forming apparatus of Example 1, toner was prepared as follows.

Styrene-n-butyl acrylate copolymer 200 parts by weight C.I. I. Pigment Blue 15: 314 14 parts by weight Saturated polyester 10 parts by weight (Terephthalic acid-propylene oxide modified bisphenol A acid value 15, peak molecular weight 6000) Metallic salicylate compound 2 parts by weight Compound (1) 15 parts by weight

The above composition was sufficiently kneaded using an extruder, crushed and crushed to a target by using a jet stream, and further using a classifier using the Counder effect, the weight average diameter was 8.2 μm and the number variation coefficient was 32%. A pulverized cyan toner was obtained. Commercially available calcium phosphate was externally added to this toner using a Henschel mixer, and the obtained toner was further dispersed in water using a homomixer, and the water temperature was gradually raised to heat treatment at 80 ° C. for 3 hours. After that, dilute hydrochloric acid was added to sufficiently dissolve and remove the calcium phosphate on the toner surface. The toner obtained by subsequent washing and drying shows a spherical shape under an electron microscope and has a shape factor SF-1.
Showed a value of 107. The weight average diameter of the toner is 7.
It was 8 μm and the number variation coefficient was 29%. By the same method, yellow toner, magenta toner, and black toner having a number 1 variation coefficient of 107 to 109 were obtained. In the toner tomographic observation, the compound (1) was not encapsulated.

When the obtained toners of respective colors were subjected to image formation by the image forming apparatus described in Example 1, a high quality image with excellent color mixture and no voids was obtained. In the 50,000-sheet durability test, the initial image density was 1.6, but the image density after the durability test was 1.5, showing a slight decrease in density, which was at a practically acceptable level. At this time, the transfer efficiency from the photosensitive member to the intermediate transfer member was 96%, and the transfer efficiency from the intermediate transfer member to the transfer material was 97%, which was a high transfer efficiency.

Example 3 Image formation was carried out in the same manner as in Example 1 except that the photoconductor prepared in the photoconductor production example 2 was used. The transfer efficiency from the photoconductor to the intermediate transfer member is 99%, the transfer efficiency from the intermediate transfer member to the transfer material is 99%, which is a high total transfer efficiency of 98%, and there is almost no transfer residual toner. Met.

Comparative Example 1 The image forming apparatus used in Example 1 was used to form an image using the following toner.

Styrene-n-butyl acrylate copolymer 200 parts by weight C.I. I. Pigment Blue 15: 314 14 parts by weight Saturated polyester 10 parts by weight (terephthalic acid-propylene oxide modified bisphenol A acid value 15, peak molecular weight 6000) Metallic salicylate compound 2 parts by weight Compound (1) 5 parts by weight

After thoroughly kneading the above composition using an extruder, crushing and colliding with a target by using a jet stream, and further using a classifier using the Counder effect, the weight average diameter was 8.3 μm and the number variation coefficient was 37%. Then, a cyan toner of SF-1 having a pulverization method of 133 was obtained. Similarly, C.I. I. Pigment Yellow 17, C.I. I. Pigment Red 202 or carbon black was used to obtain yellow toner, magenta toner, and black toner. The toner was fused and fixed to the target.

Further image formation revealed that the transfer efficiency from the photosensitive member to the intermediate transfer member was 87%, the transfer efficiency from the intermediate transfer member to the transfer material was 90%, and the total transfer efficiency was 7%.
The toner utilization efficiency was considerably low at 8.3%, and there were many problems. Even in the double-sided fixed image, offset occurred in the back side image. Even in the 50,000-sheet durability test, the initial image density was 1.
Only 03 was produced, and the image density after running was 0.9, showing a decrease in density.

Comparative Example 2 A full color copying machine (CLC-500) of the type in which a transfer material obtained by removing the intermediate transfer member from the image forming apparatus of FIG. The image drawing test was performed. Basis weight 105 g / m ²
With respect to the transfer paper of No. 2, when the transfer paper was adsorbed on the surface of the transfer roller by using an auxiliary means such as a gripper and the toner was sequentially transferred onto the paper four times, a high quality full color image could be obtained. However, when the grammage is 199 g / m ² , a partial non-uniform transfer failure is caused due to unevenness of the formation of the paper and the transfer paper is not attracted to the transfer roller. From the above, an adsorption failure was caused and a remarkable transfer failure was caused.

Comparative Example 3 Using the image forming apparatus of FIG. 1 used in Example 1, the amount of the compound (1) in the composition of Comparative Example 1 was changed to 42 parts by weight and the pulverization method was used. Used to produce four color toners.

A large amount of toner fusion was observed in the toner manufacturing apparatus, and the yield was 68%, which is lower than that obtained in Examples 1 to 3 by 10% or more. After sufficient classification, the toner has a shape factor (SF-1) of 136,
As for the particle size distribution of the toner, the weight average diameter was 8.1 μm and the number variation coefficient was 40%. 2.0% by weight of hydrophobic titanium oxide was externally added to this toner to form an image.

The transfer efficiency from the photosensitive member to the intermediate transfer member is 74.
%, And the transfer efficiency from the intermediate transfer body to the transfer material is 76%.
The total toner utilization efficiency was 56.2%, which was extremely low.

As a result of further repeated durability, toner fusion to the developing sleeve, the photosensitive member and the intermediate transfer member was observed after 500 sheets, and as a result, the transfer efficiency was decreased to 36% in total, and the image was also transferred. Only those with poor color unevenness and gradation were obtained.

Reference Example A full-color image was formed in the same manner as in Example 1 except that the fine particles of fluorocarbon, which is a fluorine compound, were not used in Production Example 1 of Photoreceptor. At this time, the transfer efficiency from the photoconductor to the intermediate transfer member was 95%, and the transfer efficiency from the intermediate transfer member to the transfer material was 99%, showing a high total transfer efficiency of 94.1%. The total transfer efficiency obtained in Example 1 was less than 97.0%.

[0133]

According to the present invention, toner fusion or filming does not occur on the photosensitive member and the intermediate transfer member, the transfer efficiency is very high, and the transfer material can be satisfactorily transferred to thick paper or small-sized transfer material. The low-temperature fixability is sufficient and a clear full-color image can be obtained. It is also suitable for obtaining a color OHP image having excellent transparency.

[Brief description of drawings]

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

FIG. 2 is a schematic diagram illustrating a toner layer of Example 1.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photoconductor (electrostatic latent image holder) 2 Charging roller 3 Exposure 4 4 color developing device (4-1,4-2,4-3,4-4) 5 Intermediate transfer body 6 Transfer material 7 Transfer roller

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G03G 9/087 15/16 G03G 9/08 384

Claims (9)

[Claims] 1. A fluorine and / or silicon atom as measured by XPS (X-ray photoelectron spectroscopy) in an extremely surface layer of a photoconductor having a laminated structure composed of a charge generation layer and a charge transport layer on at least a conductive support. SF-measured by Luzex on a photoconductor in which a compound having C is present and the ratio with the carbon atom is F / C = 0.03 to 1.00 Si / C = 0.03 to 1.00. 1 is 100 to 110 and a toner image is formed with toner particles containing a low softening point substance in an amount of 5 to 30% by weight, the toner image on the photoconductor is transferred to an intermediate transfer body, and the transfer roller is transferred. A full-color image forming method comprising: bringing a toner image on the intermediate transfer member into contact with a material, transferring the toner image on the transfer material, and fixing the toner image on the transfer material to the transfer material by heating. 2. The surface of the intermediate transfer member and the transfer roller is composed of an elastic layer, the volume specific resistance value of the intermediate transfer member is lower than the volume specific resistance value of the transfer roller, and the surface hardness of the intermediate transfer member. Has a range of 10 to 40 degrees as measured by JIS K-6301, and the hardness of the transfer roller is made larger than that of the intermediate transfer body, and the transfer roller is pressed against the intermediate transfer body to the side of the intermediate transfer body. 2. The full-color image forming method according to claim 1, wherein a voltage is applied to the transfer roller to form a toner image on the transfer material when the concave nip is formed. 3. A toner produced by a direct polymerization method in which a low softening point substance is encapsulated in an outer shell resin layer by a method of measuring a tomographic plane of a toner using a transmission electron microscope (TEM). Full-color image forming method. 4. The full-color image forming method according to claim 1, wherein the intermediate transfer member is an elastic roller having a medium resistance. 5. The full-color image forming method according to claim 1, wherein the low softening point substance is an ester wax having at least one long-chain ester portion having 10 or more carbon atoms. 6. The full-color image forming method according to claim 1, wherein the intermediate transfer member has a roller shape. 7. The full-color image forming method according to claim 1, wherein the surface layer of the photoconductor contains a polycarbonate resin. 8. The surface layer of a photoreceptor contains a polycarbonate resin synthesized from an asymmetric diol.
Full-color image forming method. 9. A protective layer is further provided on the charge transport layer,
The full-color image forming method according to claim 1, wherein a polycarbonate resin is contained in the protective layer.