JPH06208239A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To provide the electrophotographid device capable of obtaining always the picture excellent in quality. CONSTITUTION:In the electrophotographic device having an electrophotographic receptor and transfer means, the surface layer of the electrophotographic receptor is incorporated with a binder resin, the compd. particles which contains fluorine atom or silicon atom and has no compatibility to the binder resin and the compd. particles which contains fluorine atom or silicon atom and has compatibility to the binder resin, and the ratio of carbon atom to fluorine atom and silicon atom in a surface layer (F+Si)/C) by X ray optoelectronic spectrometry is 0.01-1.0 and the transfer means is a multiple transfer means. In this way, the electrophotographic device which is satisfactory in transfer and obtains always excellent picture can be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus, and more particularly to an electrophotographic apparatus having a specific electrophotographic photosensitive member and a specific transfer means.

[0002]

2. Description of the Related Art Conventionally, inorganic materials such as zinc oxide, selenium and cadmium sulfide have been known as photoconductive materials used for electrophotographic photoreceptors. Polyvinylcarbazole, phthalocyanine and azo pigments, which are organic materials, are noted for their advantages such as high productivity and non-pollution, and they tend to be inferior in terms of photoconductive properties and durability compared to inorganic materials, It has become widely used. In recent years, new materials with improved drawbacks have been investigated, and in particular, the photoconductive properties are surpassing those of inorganic materials.

On the other hand, the electrophotographic photosensitive member is repeatedly subjected to actions such as charging, exposure, development, transfer, cleaning and charge removal in the electrophotographic process of a copying machine or a laser beam printer, and therefore various chemical and physical properties are involved. Durability is required. Particularly, the surface physical properties of the photoconductor such as surface energy are involved in developer transferability on the photoconductor, stains on the photoconductor, and the like, and are one of important factors for obtaining a high-quality image. Most of the above organic photoconductive materials do not have film-forming properties by themselves, so that they are generally formed together with a binder resin or the like when forming a photosensitive layer. Therefore, factors such as the surface energy that greatly affect the surface physical properties include the characteristics of the binder resin and the like.

Conventionally used binder resins include polyester, polyurethane, polyarylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, polyamideimide, polysulfone, polyallyl ether, polyacetal, nylon and phenol resin. , Acrylic resins, silicone resins, epoxy resins, urea resins, allyl resins, alkyd resins, butyral resins, and the like, but those having more excellent surface properties are being investigated.

[0005]

By the way, in recent years, an electrophotographic process capable of faithfully reproducing a color image has been required, and several systems have been proposed. Among them, the photoconductor and the transfer drum that holds the transfer material such as transfer paper are synchronized in a one-to-one manner, and the images of four primary colors or four colors in which black is added to them are overlaid on the transfer material at a time to create a color image. An apparatus that employs a multiple transfer system that reproduces an image is generally used.

[0006] One of the problems in such a process is the transfer efficiency of the second and subsequent colors in multiple transfer. That is, since the transfer of the second color and thereafter is performed via the developer already transferred onto the transfer material, only a more indirect transfer action than usual can be given. As a result, the pre-transfer developer on the photoconductor is not sufficiently transferred to the transfer material side, and only a low quality image may be obtained due to transfer failure. In particular, when the above-mentioned conventional organic photoconductor is used, image defects such as uneven transfer of the solid image portion and voids in the transfer of the character portion are likely to occur.

Another problem is the problem of the driving load on the photoconductor. In particular, the cleaning step of removing the developer remaining on the photoconductor after transfer has a great influence on the driving load. As a cleaning method, it is preferable to employ blade cleaning in order to realize a simpler and more effective device configuration as well as space saving of the device. The blade cleaning usually has a simple structure in which an elastic member such as a plate-shaped polyurethane is merely abutted on the photosensitive member in the generatrix direction. However, when the above-mentioned conventional organic photoconductor is used, a large contact energy is generated between the photoconductor and the blade, which imposes a great load on the drive of the photoconductor. As a result, irregularities such as driving unevenness occur in the driving of the photoconductor, and color misregistration that causes a deviation in the images of the second and subsequent colors at the time of multiple transfer, and image defects such as driving pitch unevenness in which the driving unevenness causes image density unevenness, cause. In particular, in a device that forms a dot-shaped minute latent image by using a laser, an LED, a liquid crystal shutter, or the like as a light source that forms a latent image, unless the dots are superimposed with high precision during multiple transfer, micron order Color shift easily occurs, causing a color tone shift and a decrease in image sharpness.

The object of the present invention is to solve the above problems,
An object of the present invention is to provide an electrophotographic apparatus that can always obtain an image of excellent quality.

[0009]

That is, the present invention provides an electrophotographic apparatus having an electrophotographic photosensitive member and transfer means,
The surface layer of the electrophotographic photosensitive member is a binder resin, fluorine atom- or silicon atom-containing compound particles which are incompatible with the binder resin, and fluorine atom- or silicon atom-containing compound which is compatible with the binder resin. And the ratio (F + Si) / C of carbon atoms in the surface layer to fluorine atoms and silicon atoms in X-ray photoelectron spectroscopy is 0.01 to
1.0, and the transfer means is a multiple transfer means.

In the present invention, (F + Si) / C is 0.
If it is less than 01, the image may be deteriorated due to insufficient transfer or drive unevenness, and if it exceeds 1.0, the strength and adhesiveness of the phase itself may be deteriorated or the image may be caused by light scattering of resin particles. May deteriorate.

(F + Si) / C is of course affected by the kind and amount of the material used, but also shows a different value depending on the dispersed state of other particles and the surface state of the photosensitive member.

Examples of the fluorine atom-containing compound used in the present invention include tetrafluoroethylene, hexafluoropropylene, trifluoroethylene, chlorotrifluoroethylene, vinylidene fluoride, in addition to fluorinated graphato.
Examples thereof include polymers and copolymers of vinyl fluoride and perfluoroalkyl vinyl ether, and graft polymers and block polymers containing these in the molecule. As the silicon atom-containing compound, 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, a surfactant, Examples include macromonomers and terminal-modified polydimethylsiloxane.

In the present invention, these materials are used in combination with compound particles which are incompatible with the binder resin described later and a compound which is compatible with them. The particle size of the compound particles is preferably 0.01 to 5 μm in weight average particle size, and particularly preferably 0.01 to 0.35 μm. The molecular weight of the resin particles is preferably 3,000 to 5,000,000 in terms of weight average molecular weight. Further, the content of the compound particles is preferably 10 to 70% by weight, and particularly preferably 20 to 60% by weight based on the total weight of the layer containing the compound particles. Further, the content of the compound compatible with the binder resin,
It is preferably 0.1 to 50% by weight, and particularly preferably 0.1 to 30% by weight, based on the total weight of the compound particles in the layer containing the compound.

The photosensitive layer of the electrophotographic photosensitive member used in the present invention has a single layer or a laminated structure. In the case of a single layer structure,
Generation and transfer of carriers are performed in the same layer, and a compound containing a fluorine atom or a silicon atom is contained in this layer which is the outermost surface layer. In the case of a laminated structure, a charge generation layer that generates carriers and a charge transport layer that moves carriers are laminated. The surface layer may be formed by either the charge generation layer or the charge transport layer, but in any case,
The compound containing a fluorine atom or a silicon atom is contained in the layer forming the outermost surface layer.

The thickness of the single-layer type photosensitive layer is preferably 5 to 100 μm, and particularly preferably 10 to 60 μm. The content of the charge-generating material that generates carriers and the charge-transporting material that transports carriers is preferably 20 to 80% by weight based on the total weight of the photosensitive layer, and particularly 3
It is preferably from 0 to 70% by weight. In the case of a laminated type photosensitive layer, the thickness of the charge generation layer is preferably 0.001 to 6 μm, and particularly preferably 0.01 to 2 μm. The content of the charge generating material is preferably 10 to 100% by weight, and particularly preferably 40 to 100% by weight based on the total weight of the charge generating layer. The thickness of the charge transport layer is preferably 5 to 100 μm, and particularly preferably 10 to 60 μm. The content of the charge transport material is 20 to 80% by weight based on the total weight of the charge transport layer.
Is preferable, and particularly preferably 30 to 70% by weight.

The charge generating material used in the present invention includes phthalocyanine pigments, polycyclic quinone pigments, azo pigments,
Perylene pigment, indigo pigment, quinacridone pigment, azurenium salt dye, squarylium dye, cyanine dye,
Pyrylium dyes, thiopyrylium dyes, xanthene dyes, quinonimine dyes, triphenylmethane dyes, styryl dyes, selenium, selenium-tellurium, amorphous silicon, and cadmium sulfide can be mentioned. The charge transport material used in the present invention includes pyrene compounds, carbazole compounds, hydrazone compounds, N, N-dialkylaniline compounds, diphenylamine compounds, triphenylamine compounds, triphenylmethane compounds, pyrazoline compounds, styryl compounds and stilbene compounds. A compound etc. are mentioned.

These materials are used by dispersing or dissolving in a suitable binder resin, and examples of such binder resin include polyester, polyurethane, polyarylate, polyethylene, polystyrene, polybutadiene,
Polycarbonate, polyamide, polypropylene, polyimide, polyamideimide, polysulfone, polyallyl ether, polyacetal, nylon, phenol resin, acrylic resin, silicone resin, epoxy resin, urea resin, allyl resin, alkyd resin and butyral resin are preferable. Furthermore, reactive epoxy, (meth)
It is also preferable that the acrylic monomer or oligomer is mixed with the above-mentioned resin and then cured and used. Among these, polyarylate, polycarbonate and polyallyl ether are particularly preferable.

In the present invention, it is more preferable that the electrophotographic photosensitive member has a protective layer on the photosensitive layer. The thickness of the protective layer is preferably 0.01 to 20 μm,
It is particularly preferably 0.1 to 10 μm. The protective layer may contain the above-mentioned charge generation material or charge transport material. At this time, the fluorine atom- or silicon atom-containing compound is contained in at least the protective layer which is the outermost surface layer. Examples of the binder resin that can be used in the protective layer include the same resins as those that can be used in the photosensitive layer.

The compound containing a fluorine atom or a silicon atom used in the present invention is used by dispersing or dissolving it in the above-mentioned binder resin, and as a dispersing means, a sand mill, a ball mill, a roll mill, a homogenizer, a nanomizer, a paint shaker and an ultrasonic wave are used. Etc.

An undercoat layer may be provided between the conductive substrate and the photosensitive layer. The undercoat layer is mainly made of resin, but may contain the conductive material or the acceptor substance. As the resin forming the undercoat layer, polyester, polyurethane,
Polyarylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, polyamideimide, polysulfone,
Examples thereof include polyallyl ether, polyacetal, nylon, phenol resin, acrylic resin, silicone resin, epoxy resin, urea resin, allyl resin, alkyd resin and butyral resin.

These various layers are applied and formed on a conductive support by a bar coating method, a knife coating method, a roll coating method, a spray coating method, a dip coating method, an electrostatic coating method, a powder coating method or the like. .

The conductive support used in the electrophotographic photoreceptor of the present invention includes iron, copper, nickel, aluminum,
Examples thereof include metals and alloys such as titanium, tin, antimony, indium, lead, zinc, gold and silver, oxides or graphates thereof, conductive resins, and resins in which these conductive materials are dispersed. The shape may be a cylindrical shape, a belt shape, or a sheet shape, but it is preferably the most suitable shape depending on the applied electrophotographic apparatus.

The schematic structure of the electrophotographic apparatus according to the present invention is shown in FIGS. In FIG. 1, reference numeral 1 is a drum-shaped electrophotographic photosensitive member, 2 is a transfer drum, and the photosensitive member and the transfer drum have independent drive systems when driven by gears, belts, etc. There are cases. In any case, the photoconductor 1 and the transfer drum 2 need to be superimposed on each other in the first color image at the time of transfer, and therefore, control for synchronizing with each other is performed. In the example of FIG. 1, the three-color or four-color developing means is of a rotary type with respect to the photoconductor. This electrophotographic device can be used as an output device for a copying machine, a printer, a facsimile, and the like.

The image forming process is basically carried out in the order of charging, exposure, development, transfer, cleaning, and charge removal, and by repeating these in sequence, color superposition is performed and a color image is reproduced. First, after charging the surface of the photoconductor 1 with a charging device 3 such as a corotron or a scorotron, a laser controlled by a digital image signal sent from a storage device 4, information processing such as a reading device or a computer, A light source 5 such as an LED and a liquid crystal shutter emits a dot-shaped minute optical image onto the photoconductor. This optical image generates charge carriers in the photoconductor and erases the surface charge of the photoconductor to form a dot-shaped minute electrostatic latent image. The image signal is color-separated into three colors of cyan, magenta and yellow, or four colors obtained by adding black to them, and after an electrostatic latent image corresponding to each color is formed, each color is separated into each color. Development is sequentially performed by the corresponding developing machine 6. In addition to the arrangement shown in FIG. 1, the three-color or four-color developing means is arranged in a fixed system (FIG. 2), a lateral movement system (FIG. 3), or a vertical movement system (FIG. 2). According to 4), there is a moving method in which the photosensitive members are sequentially contacted. The present invention can be applied to any of these methods.

The image developed by the developer is transferred by the transfer means 7.
Is transferred to a transfer material P such as a transfer paper in a transfer process. The transfer material is electrostatically or mechanically fixed to the surface of the transfer drum 2 in order to transfer the images of three colors or four colors in a multiple manner on one transfer material. Further, the image starting point and the image area of the photoconductor 1 and the transfer drum 2 are controlled in synchronization at least during the multiple transfer process of the same image onto the same transfer material so that the images of the respective colors are not displaced during the multiple transfer. It A corotron, a scorotron, a conductive brush, a conductive roller, or the like is mainly used as a transfer unit that transfers the developer from the photoconductor onto the transfer material, due to an electrostatic force having a polarity opposite to that of the developer. At the same time, a pressure member may be used together to impart a transfer effect by pressure. In order to support the transfer material P, the transfer drum 2 is generally one in which a film, a mesh or the like is stretched in a cylindrical shape on a cylindrical frame. Materials for such films and meshes include polyethylene terephthalate, polycarbonate, polyester, polysulfone, polyarylate, polyphenylene oxide, polyimide, polyamide, nylon, polyethylene oxide,
Various resins such as polystyrene and polyacetal, and polymer alloys containing them are used. Further, the film and mesh may contain a conductive material such as metal, metal oxide, graphat and conductive polymer.

The residual developer after transfer is cleaning means 8
Excluded by. As a cleaning method, it is desirable to adopt blade cleaning in order to realize a simpler device configuration in association with space saving of the device. The blade cleaning has a simple configuration in which an elastic member such as a plate-shaped polyurethane is merely abutted on the photoconductor in the generatrix direction. The contact direction of blade cleaning is
There are a forward direction in which the blade tip is oriented in the rotation direction of the photoconductor 1, a counter direction in which the blade tip is oriented in the direction opposite to the rotation direction of the photoconductor, and a case where the photoconductor and the blade are vertical. Further, the blade is not limited to a single blade, but a plurality of blades can be used together. Further, a cleaning brush, a web, a magnetic brush or the like may be used in combination as an auxiliary.

The cleaned photoconductor is then decharged by the pre-exposure means 9.

On the other hand, the transfer material P onto which the image has been transferred is separated from the photoconductor 1 and reaches the image fixing means 10, where it is subjected to image fixing and then discharged as a copy. . Reference numeral 11 indicates a tray that holds the transfer material P.

Hereinafter, the present invention will be described in more detail with reference to examples.

[0030]

【Example】

[Example 1] 10 parts of conductive titanium oxide coated with tin oxide (weight average particle size 0.4 μm) (parts by weight, the same hereinafter), 10 parts of a phenol resin precursor (resole type), 10 parts of methanol and butanol. A dispersion liquid obtained by dispersing a solution dissolved in 10 parts of a mixed solvent by using a sand mill is applied onto an aluminum cylinder having an outer diameter of 80 mm and a length of 360 mm by a dip coating method and cured at 140 ° C. to obtain a volume resistance of 5 A conductive layer having a thickness of 10 ⁹ Ωcm and a thickness of 20 μm was formed.

Next, 10 parts of methoxymethylated nylon (weight average molecular weight of 30,000, degree of methoxymethylation of about 30%) represented by the following formula:

[0032]

[Chemical 1] Was dissolved in 150 parts of isopropanol to form a subbing layer having a thickness of 1 μm on the conductive layer by dip coating and drying.

Next, 10 parts of an azo pigment represented by the following formula:

[0034]

[Chemical 2] And 5 parts of a polycarbonate resin (weight average molecular weight 30,000) represented by the following formula

[0035]

[Chemical 3] A dispersion liquid prepared by dispersing a solution of 700 parts of cyclohexanone in a sand mill was applied onto the undercoat layer by a dip coating method and dried to give a thickness of 0.05 μm.
m charge generating layer was formed.

Next, 10 parts of triphenylamine represented by the following formula:

[0037]

[Chemical 4] And 10 parts of a polycarbonate resin (weight average molecular weight 20,000) represented by the following formula:

[0038]

[Chemical 5] A solution prepared by dissolving 50 parts of monochlorobenzene and 15 parts of dichloromethane in a mixed solvent is applied onto the charge generation layer by a dip coating method and dried with hot air to give a thickness of 2
A 0 μm charge transport layer was formed.

Next, 1 part of fine graphite fluoride powder (weight average particle size 0.23 μm, manufactured by Central Glass Co., Ltd.), 6 parts of a polycarbonate resin represented by the following formula (weight average molecular weight 80,000),

[0040]

[Chemical 6] And 0.1 part of a perfluoroalkyl acrylate-methyl methacrylate block copolymer (weight average molecular weight 30,000) represented by the following formula:

[0041]

[Chemical 7] (N is an integer of 4 to 16 and i and j are copolymerization ratios.) In a solution dispersed and dissolved in a mixed solvent of 120 parts of monochlorobenzene and 80 parts of dichloromethane, triphenylamine 3 represented by the following formula: Department

[0042]

[Chemical 8] Was dissolved on the charge transport layer by a spray coating method and dried to form a protective layer having a thickness of 5 μm.

The obtained electrophotographic photosensitive member was evaluated by the following methods.

[(F + Si) / C] The surface of the photoconductor was cut into a size of 4 cm × 4 cm, and this sample was ESCALAB200-X manufactured by VG.
Quantitative analysis of surface elements was performed using a type X-ray photoelectron spectrometer. X
2mm x 3m using MgCa (300W) as a radiation source
The measurement was carried out at a depth of several angstroms for the area of m. The obtained chart is shown in FIG. As a result, 5.2% fluorine atoms, 0% silicon atoms, 8 carbon atoms
It was 1.3% and (F + Si) / C was 0.064.

[Contact Angle] The contact angle of pure water on the surface of the photosensitive drum was measured with a dropping type contact angle meter (manufactured by Kyowa Interface Science Co., Ltd.). As a result, the contact angle of the photoconductor of Example 1 was 108 degrees, which was a sufficiently low surface energy.

[Transfer Efficiency] A photoconductor was attached to the electrophotographic apparatus shown in FIG. 1 and the initial transfer efficiency was measured. Negative polarity scorotron is used for charging, and wavelength is 787n for exposure.
m laser was used. A two-component negative polar developer was used as the developer, and transfer was performed with a corotron having a positive polarity through a polyethylene terephthalate film having a thickness of 100 μm. The transfer efficiency was calculated after measuring the developer density transferred to the transfer material and the developer density remaining on the photoconductor with a reflection type Macbeth densitometer when the halftone solid pattern was output in a single color. . The image density of the halftone solid pattern was set to 0.80 by the reflection type Macbeth density measurement on the transfer material. As a result, the transfer efficiency was as high as 93%.

[Transfer unevenness] A photoconductor was attached to the electrophotographic apparatus shown in FIG. 1 and a halftone solid pattern image after four-color multiple transfer was output. The image evaluation was performed on the image after 1000 sheets were continuously output. The calculation formula was the transferred developer concentration / (transferred developer concentration + residual developer concentration). Further, the image density of the halftone solid pattern image is 1.20 on average with a reflection type Macbeth densitometer.
And As a result, a uniform image was obtained.

[Transmission void] A photoconductor was attached to the electrophotographic apparatus shown in FIG. 1 and a character pattern image after four-color multiple transfer was output. The image evaluation was performed on the image after continuous output of 1000 sheets. As a result, a uniform character pattern was obtained even after 1000 sheets.

[Driving Pitch Unevenness] A photoconductor was attached to the electrophotographic apparatus shown in FIG. 1, and a halftone solid pattern image after four-color multiple transfer was output. The image evaluation was performed on the image after continuous output of 1000 sheets. As a result, 100
A uniform pattern was obtained even in the halftone solid pattern after 0 sheets.

[Color Misregistration] A photoconductor was attached to the electrophotographic apparatus shown in FIG. 1 and a gray halftone solid pattern image after four-color multiple transfer was output. The image evaluation was performed on the image after continuous output of 1000 sheets. As a result, 1000
A uniform color tone pattern was obtained even in the gray halftone solid pattern after printing.

Comparative Example 1 An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that the protective layer was not provided.

The results are shown below.

[(F + Si) / C] From FIG. 7, fluorine atom and silicon atom are 0%, and (F + Si) / C is 0.
Met.

[Contact angle] The contact angle was 82 degrees.

[Transfer efficiency] The transfer efficiency was 86%.

[Transfer unevenness] A non-uniform image with a large amount of roughness due to partial transfer omission.

[Transmission void] As shown in FIG. 8, a portion other than the outline of the character pattern was lost due to a transfer defect, and a transfer void was generated.

[Driving pitch unevenness] Irregular stripe-like unevenness of the image was generated in the direction of the rotation axis of the photoconductor.

[Color Misregistration] Partially reddish unevenness occurred. When this output image was observed with a microscope, in a dot-shaped image in which four color dots were overlapped, the magenta image among the four colors was shifted by 50 to 90 μm, and it was found that the uneven color tone was caused by a micro color shift.

Example 2 In the same manner as in Example 1, a conductive layer, an undercoat layer and a charge generation layer were formed on an aluminum cylinder.

Next, a charge transport layer was formed in the same manner as in Example 1 except that triphenylamine represented by the following formula was used instead of the triphenylamine used in Example 1.

[0062]

[Chemical 9] Next, fluorinated graphato fine powder (weight average particle size 0.23
μm, manufactured by Central Glass Co., Ltd.) 3 parts, polycarbonate resin represented by the following formula (weight average molecular weight 80,000)
5 copies,

[0063]

[Chemical 10] And 0.3 part of a perfluoroalkyl acrylate-methyl methacrylate block copolymer (weight average molecular weight 30,000) represented by the following formula:

[0064]

[Chemical 11] (N is an integer of 4 to 16 and i and j are copolymerization ratios.) In a solution dispersed and dissolved in a mixed solvent of 110 parts of monochlorobenzene and 80 parts of dichloromethane, triphenylamine 2 represented by the following formula: .5 copies

[0065]

[Chemical 12] The solution in which was dissolved was applied onto the charge transport layer by a spray coating method and dried to form a protective layer having a thickness of 6 μm.

The obtained electrophotographic photosensitive member was evaluated in the same manner as in Example 1. As a result, 10.2% of fluorine atoms,
Silicon atom is 0% and carbon atom is 76.7% (F
+ Si) / C was 0.13, and the contact angle was 113 degrees. In addition, the transfer efficiency was 96%, and a very excellent image could be obtained without transfer unevenness, omission of transfer, drive pitch unevenness and color misregistration.

Example 3 In the same manner as in Example 1, a conductive layer, an undercoat layer and a charge generating layer were formed on an aluminum cylinder.

Next, instead of 10 parts of triphenylamine used in Example 1, 3 parts of triphenylamine represented by the following formula:

[0069]

[Chemical 13] And 7 parts of triphenylamine represented by the following formula,

[0070]

[Chemical 14] A charge transport layer was formed in the same manner as in Example 1 except that

Next, 3 parts of fluorinated graphato fine powder (weight average particle size 0.27 μm, manufactured by Central Glass Co., Ltd.) and a polycarbonate resin represented by the following formula (weight average molecular weight 8
50,000) 5.5 parts,

[0072]

[Chemical 15] And a fluorine atom-containing graft polymer represented by the following formula (fluorine content: 27% by weight, weight average molecular weight: 25,000)
0) 0.3 parts

[0073]

[Chemical 16] (M and n each represent an integer of 4 to 16, and i and j each represent a copolymerization ratio.) A triphenyl group represented by the following formula was added to a solution dispersed and dissolved in a mixed solvent of 120 parts of monochlorobenzene and 80 parts of dichloromethane. 2.5 parts amine

[0074]

[Chemical 17] Was dissolved on the charge transport layer by a spray coating method and dried to form a protective layer having a thickness of 4 μm.

The obtained electrophotographic photosensitive member was evaluated in the same manner as in Example 1. As a result, fluorine atoms are 11.3%,
Silicon atom is 0% and carbon atom is 75.5% (F
+ Si) / C was 0.15, and the contact angle was 114 degrees. Further, the transfer efficiency was 96%, and a very excellent image without transfer unevenness, omission of transfer, drive pitch unevenness and color misregistration could be obtained.

Example 4 The same as Example 3 except that the fluorine atom-containing graft polymer used in Example 3 was replaced with the perfluoroalkyl acrylate-methyl methacrylate block copolymer used in Example 1. hand,
An electrophotographic photosensitive member was prepared and evaluated.

As a result, the fluorine atom content was 12.2%, the silicon atom content was 0%, and the carbon atom content was 73.2% (F + S).
i) / C was 0.17 and the contact angle was 115 degrees. In addition, the transfer efficiency was 95%, and a very excellent image could be obtained without transfer unevenness, omission of transfer, drive pitch unevenness and color misregistration.

Example 5 In the same manner as in Example 1, a conductive layer, an undercoat layer and a charge generation layer were formed on an aluminum cylinder.

Next, 3 parts of triphenylamine represented by the following formula:

[0080]

[Chemical 18] 7 parts of triphenylamine represented by the following formula,

[0081]

[Chemical 19] And 10 parts of a polycarbonate resin (weight average molecular weight 25,000) represented by the following formula,

[0082]

[Chemical 20] A solution prepared by dissolving 50 parts of monochlorobenzene and 15 parts of dichloromethane in a mixed solvent is applied onto the charge generation layer by a dip coating method and dried with hot air to give a thickness of 2
A 0 μm charge transport layer was formed.

Next, tetrafluoroethylene-hexafluoropropylene copolymer fine powder (monomer ratio tetrafluoroethylene / hexafluoropropylene = 3 /
7, emulsion polymerization fine powder, weight average particle size 0.32
μm, weight average molecular weight about 600,000) 3 parts, polycarbonate resin represented by the following formula (weight average molecular weight 10
50,000) 5.5 parts,

[0084]

[Chemical 21] And 0.3 part of a perfluoroalkyl acrylate-methyl methacrylate block copolymer represented by the following formula (weight average molecular weight 30,000)

[0085]

[Chemical formula 22] (N is an integer of 4 to 16 and i and j are copolymerization ratios.) In a solution dispersed and dissolved in a mixed solvent of 100 parts of monochlorobenzene and 70 parts of dichloromethane, triphenylamine 2 represented by the following formula: .5 copies

[0086]

[Chemical formula 23] Was dissolved on the charge transport layer by a spray coating method and dried to form a protective layer having a thickness of 5 μm.

The obtained electrophotographic photosensitive member was evaluated in the same manner as in Example 1. As a result, fluorine atoms were 9.5%, silicon atoms were 0%, carbon atoms were 80.5% (F +
Si) / C was 0.12 and the contact angle was 112 degrees. Further, the transfer efficiency was 96%, and a very excellent image without transfer unevenness, omission of transfer, drive pitch unevenness and color misregistration could be obtained.

[Comparative Example 2] In the same manner as in Example 1, a conductive layer, an undercoat layer and a charge generating layer were formed on an aluminum cylinder.

Then, 10 parts of triphenylamine represented by the following formula:

[0090]

[Chemical formula 24] And 10 parts of a polycarbonate resin having a structure represented by the following formula (weight average molecular weight 25,000):

[0091]

[Chemical 25] A solution dissolved in 50 parts of monochlorobenzene and 15 parts of dichloromethane was applied onto the charge generation layer by a dip coating method, and dried with hot air to form a charge transport layer having a thickness of 20 μm.

Next, 0.3 part of fluorinated graphato fine powder (weight average particle size 0.27 μm, manufactured by Central Glass Co., Ltd.),
6.4 parts of a polycarbonate resin represented by the following formula (weight average molecular weight 80,000),

[0093]

[Chemical formula 26] And 0.03 part of a perfluoroalkyl acrylate-methyl methacrylate block copolymer (weight average molecular weight 30,000) represented by the following formula:

[0094]

[Chemical 27] (N is an integer of 4 to 16 and i and j are copolymerization ratios.) In a solution dispersed and dissolved in a mixed solvent of 120 parts of monochlorobenzene and 80 parts of dichloromethane, triphenylamine 3 represented by the following formula: .2 copies

[0095]

[Chemical 28] Was dissolved on the charge transport layer by a spray coating method and dried to form a protective layer having a thickness of 5 μm.

The obtained electrophotographic photosensitive member was evaluated in the same manner as in Example 1. As a result, fluorine atoms are 0.83%,
Silicon atom is 0% and carbon atom is 85.5% (F
+ Si) / C was 0.0097, and the contact angle was 83 degrees. In addition, the transfer efficiency was 87%, and transfer unevenness, omission of transfer, drive pitch unevenness, and color misregistration occurred.

Example 6 In the same manner as in Example 1, a conductive layer, an undercoat layer, a charge generation layer and a charge transport layer were formed on an aluminum cylinder.

Next, 1 part of true spherical three-dimensional crosslinked polysiloxane fine particles (weight average particle diameter 0.29 μm, manufactured by Toshiba Silicone Co., Ltd.), 6 parts of a polycarbonate resin represented by the following formula (weight average molecular weight 80,000),

[0099]

[Chemical 29] And a polydimethylsiloxane methacrylate-methyl methacrylate block copolymer represented by the following formula (silicon content 22% by weight, weight average molecular weight 50,000)
0.1 part

[0100]

[Chemical 30] (N is a positive integer, and i and j are copolymerization ratios.)
To a solution dispersed and dissolved in a mixed solvent of 120 parts of monochlorobenzene and 80 parts of dichloromethane, 3 parts of triphenylamine represented by the following formula

[0101]

[Chemical 31] Was applied to the charge transport layer by a spray coating method and dried to form a protective layer having a thickness of 3 μm.

The obtained electrophotographic photosensitive member was evaluated in the same manner as in Example 1.

[(F + Si) / C] FIG. 6 shows a chart obtained by X-ray photoelectron spectroscopy measurement. As a result, fluorine atoms are 0% and silicon atoms are 1
Carbon atom is 62.3% at 0.2%, (F + Si)
/ C was 0.16.

[Contact Angle] The contact angle was 107 degrees.

[Transfer Efficiency] The transfer efficiency was 92%.

[Transfer unevenness] As in Example 1, a uniform image was obtained.

[Transmitting void] A uniform character pattern was obtained as in Example 1.

[Driving pitch unevenness] A uniform pattern was obtained as in Example 1.

[Color Misregistration] A uniform color tone pattern was obtained as in Example 1.

Example 7 In the same manner as in Example 2, a conductive layer, an undercoat layer, a charge generation layer and a charge transport layer were formed on an aluminum cylinder.

Next, 3 parts of true spherical three-dimensional crosslinked polysiloxane fine particles (weight average particle diameter 0.29 μm, manufactured by Toshiba Silicone Co., Ltd.), 4 parts of a polycarbonate resin represented by the following formula (weight average molecular weight 80,000),

[0112]

[Chemical 32] And a polydimethylsiloxane methacrylate-styrene block copolymer represented by the following formula (silicon content 2
2 wt%, weight average molecular weight 60,000) 0.3 part,

[0113]

[Chemical 33] (N is a positive integer, and i and j are copolymerization ratios.)
2.5 parts of triphenylamine represented by the following formula in a solution dispersed and dissolved in a mixed solvent of 120 parts of monochlorobenzene and 80 parts of dichloromethane.

[0114]

[Chemical 34] Was applied to the charge transport layer by a spray coating method and dried to form a protective layer having a thickness of 3 μm.

The resulting electrophotographic photosensitive member was evaluated in the same manner as in Example 1. As a result, 0% fluorine atoms, 15.1% silicon atoms and 58.1% carbon atoms,
(F + Si) / C was 0.26 and the contact angle was 110 degrees. Further, the transfer efficiency was 94%, and a very excellent image without transfer unevenness, omission of transfer, drive pitch unevenness and color misregistration could be obtained.

Example 8 In the same manner as in Example 3, a conductive layer, an undercoat layer, a charge generation layer and a charge transport layer were formed on an aluminum cylinder.

Next, 3 parts of true spherical three-dimensional crosslinked polysiloxane fine particles (weight average particle diameter 0.29 μm, manufactured by Toshiba Silicone Co.), 4 parts of a polycarbonate resin represented by the following formula (weight average molecular weight 80,000),

[0118]

[Chemical 35] And 0.35 part of a silicon atom-containing graft polymer (weight average molecular weight 35,000) represented by the following formula:

[0119]

[Chemical 36] (M and n are positive integers, i, j and k are copolymerization ratios.) Triphenyl represented by the following formula is added to a solution dispersed and dissolved in a mixed solvent of 120 parts of monochlorobenzene and 80 parts of dichloromethane. 2.5 parts amine

[0120]

[Chemical 37] The solution in which is dissolved is applied onto the charge transport layer by a spray coating method and dried to give a thickness of 3.5 μm.
To form a protective layer.

The obtained electrophotographic photosensitive member was evaluated in the same manner as in Example 1. As a result, fluorine atoms are 0%, silicon atoms are 16.3%, carbon atoms are 57.3% (F + S
i) / C was 0.28 and the contact angle was 110 degrees. Further, the transfer efficiency was 94%, and a very excellent image without transfer unevenness, omission of transfer, drive pitch unevenness and color misregistration could be obtained.

[Example 9] The same as Example 8 except that the polydimethylsiloxane acrylate-methyl methacrylate block copolymer used in Example 6 was used in place of the silicon atom-containing graft polymer used in Example 8. Then, an electrophotographic photosensitive member was prepared and evaluated.

As a result, the fluorine atom content was 0%, the silicon atom content was 15.6%, and the carbon atom content was 58.5% (F + Si).
/ C was 0.27 and the contact angle was 110 degrees. Further, the transfer efficiency was 94%, and a very excellent image without transfer unevenness, omission of transfer, drive pitch unevenness and color misregistration could be obtained.

[Comparative Example 3] In the same manner as in Comparative Example 2, a conductive layer, an undercoat layer, a charge generation layer and a charge transport layer were formed on an aluminum cylinder.

Next, 0.5 part of true spherical three-dimensional crosslinked polysiloxane fine particles (weight average particle diameter 0.29 μm, manufactured by Toshiba Silicone Co., Ltd.) and 4 parts of a polycarbonate resin represented by the following formula (weight average molecular weight 80,000). To

[0126]

[Chemical 38] 2.5 parts of triphenylamine represented by the following formula in a solution dispersed and dissolved in a mixed solvent of 120 parts of monochlorobenzene and 80 parts of dichloromethane.

[0127]

[Chemical Formula 39] Was applied to the charge transport layer by a spray coating method and dried to form a protective layer having a thickness of 3 μm.

The obtained electrophotographic photosensitive member was evaluated in the same manner as in Example 1. As a result, fluorine atoms are 0%, silicon atoms are 0.53%, carbon atoms are 83.3% (F + S
i) / C was 0.0064 and the contact angle was 82 degrees. In addition, the transfer efficiency was 84%, and transfer unevenness, omission of transfer, drive pitch unevenness, and color misregistration occurred.

[0129]

As described above, according to the present invention, it is possible to provide an electrophotographic apparatus in which transfer is excellent and an excellent image is always obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a configuration of an electrophotographic apparatus used in this example.

FIG. 2 is a diagram schematically showing a configuration of an electrophotographic apparatus that can be used in the present invention.

FIG. 3 is a diagram schematically showing a configuration of an electrophotographic apparatus that can be used in the present invention.

FIG. 4 is a diagram schematically showing a configuration of an electrophotographic apparatus that can be used in the present invention.

5 is a diagram showing a chart obtained by X-ray photoelectron spectroscopy measurement of the electrophotographic photosensitive member prepared in Example 1. FIG.

FIG. 6 is a view showing a chart obtained by X-ray photoelectron spectroscopy measurement of the electrophotographic photosensitive member prepared in Example 6;

7 is a diagram showing a chart obtained by X-ray photoelectron spectroscopy measurement of the electrophotographic photosensitive member prepared in Comparative Example 1. FIG.

FIG. 8 is a diagram illustrating an example of an image in which a void in transfer occurs.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrophotographic photosensitive member 2 Transfer drum 3 Charging device 4 Information processing and storage medium 5 Light source 6 Developing means 7 Transfer means 8 Cleaning means 9 Pre-exposure means 10 Image fixing means 11 Tray

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shoji Amamiya 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masaaki Yamagami 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (7)

[Claims] 1. In an electrophotographic apparatus having an electrophotographic photosensitive member and a transfer means, the surface layer of the electrophotographic photosensitive member is a binder resin, and a compound containing a fluorine atom or a silicon atom which is incompatible with the binder resin. Particles and a fluorine atom- or silicon atom-containing compound having compatibility with the binder resin are contained, and the ratio of carbon atoms in the surface layer in X-ray photoelectron spectroscopy to fluorine atoms and silicon atoms (F + S
i) / C is 0.01 to 1.0, and the transfer means is a multiple transfer means. 2. The surface layer contains a binder resin, fluorine atom-containing compound particles that are not compatible with the binder resin, and a fluorine atom-containing compound that is compatible with the binder resin. The electrophotographic apparatus according to claim 1, wherein the ratio F / C of fluorine atoms is 0.01 to 1.0. 3. The surface layer contains a binder resin, silicon atom-containing compound particles that are incompatible with the binder resin, and a silicon atom-containing compound that is compatible with the binder resin,
Ratio of carbon atoms and silicon atoms Si / C is 0.01 to
The electrophotographic apparatus according to claim 1, which is 1.0. 4. The electrophotographic apparatus according to claim 1, wherein the electrophotographic photosensitive member has a photosensitive layer on a conductive support, and the surface layer is the photosensitive layer. 5. The electrophotographic apparatus according to claim 1, wherein the electrophotographic photosensitive member has a photosensitive layer on a conductive support, a protective layer on the photosensitive layer, and the surface layer is a protective layer. 6. The weight average particle diameter of the compound particles is from 0.01 to
The electrophotographic apparatus according to claim 1, having a size of 0.35 μm. 7. The electrophotographic apparatus according to claim 1, wherein the image transferred by the transfer means is an image obtained by developing a minute dot-shaped electrostatic latent image.