JP3253205B2 - Electrophotographic photoreceptor, electrophotographic apparatus and apparatus unit having the electrophotographic photoreceptor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photoreceptor having a protective layer, and more particularly, to an electrophotographic photoreceptor having excellent image uniformity, high durability, excellent slipperiness and improved electrophotographic properties. And an electrophotographic apparatus having the electrophotographic photosensitive member.

[0002]

2. Description of the Related Art An electrophotographic photosensitive member is charged, exposed, developed,
Means such as transfer, cleaning and static elimination are repeatedly applied. The electrostatic latent image formed by charging and exposure becomes a toner image by a fine particle developer called toner. Further, the toner image is transferred to a transfer material such as paper by a transfer unit, but not all the toner is transferred, and a part thereof remains on the surface of the photoconductor.

If the amount of the residual toner is large, the image on the transfer material is in a so-called uneven shape, which causes a further transfer failure, so that not only lack of image uniformity but also fusion of the toner to the photoreceptor and filming are caused. The problem of the occurrence of the problem occurs. For these problems, it is required to improve the releasability of the surface layer of the photoreceptor.

Further, since the electrophotographic photosensitive member is directly applied with the above-mentioned electrical and mechanical external force, durability against the external force is required. Specifically, it is required to have durability against abrasion and scratches on the surface due to rubbing, and deterioration of the surface layer due to adhesion of an active substance such as ozone or NOx generated during charging.

Attempts have been made to provide various protective layers in order to satisfy the above-mentioned characteristics required for an electrophotographic photosensitive member. Among them, many protective layers containing a resin as a main component have been proposed. For example, JP-A-57-30846 proposes a protective layer whose resistance can be controlled by adding a metal oxide as a conductive powder to a resin.

Dispersing a metal oxide in a protective layer for an electrophotographic photoreceptor controls the electrical resistance of the protective layer itself and prevents an increase in the residual potential in the photoreceptor due to repetition of the electrophotographic process. Is the main purpose, while a suitable resistance value of the protective layer for the electrophotographic photosensitive member is 10 ¹⁰ to 10 ¹⁵ oh
It is known to be m · cm. However, in the resistance value in the above-mentioned range, the electric resistance of the protective layer is easily affected by ionic conduction, and therefore, the electric resistance tends to largely change due to a change in environment. In particular, when the metal oxide is dispersed in the film, the water absorption of the metal oxide surface is high, so that the resistance of the protective layer falls within the above range in all environments and when the electrophotographic process is repeated. Up to now it has been very difficult.

Particularly under high humidity, active substances such as ozone and NOx generated by charging repeatedly adhere to the surface, thereby lowering the resistance of the photoreceptor surface and the releasability of the toner from the surface layer. This causes problems such as image blurring and insufficient image uniformity.

In general, when particles are dispersed in the protective layer, the particle diameter of the particles must be smaller than the wavelength of the incident light, that is, in order to prevent scattering of the incident light by the dispersed particles.
Preferably it is 3 μm or less. However, metal oxide particles usually tend to agglomerate in a resin solution and are difficult to disperse uniformly, and even once dispersed, secondary agglomeration and precipitation tend to occur. It was very difficult to produce it stably. Further, from the viewpoint of improving transparency and conductivity uniformity, it is preferable to disperse an ultrafine particle having a particularly small particle size (a primary particle diameter of 0.1 μm or less). However, the dispersibility and dispersion stability of such an ultrafine particle are preferable. Tended to be even worse.

In order to make up for the above disadvantages, for example, Japanese Patent Laid-Open
JP-A-306857 discloses a fluorine-containing silane coupling agent, a titanate coupling agent or C ₇ F ₁₅ NC.
O and other compounds are added to form a protective layer.
Japanese Patent No. 5066 discloses a protective layer in which a metal fine powder or a metal oxide fine powder having improved dispersibility and moisture resistance by water-repellent treatment is dispersed in a binder resin.
No. 67 discloses protection of a binder resin in which a titanate coupling agent, a fluorine-containing silane coupling agent, a fluorine-containing silane coupling agent, and a metal oxide fine powder surface-treated with acetoalkoxyaluminum diisopropylate are dispersed. Layers and the like have been proposed.

[0010] However, even in these protective layers, the releasability of the binder resin used for the protective layer itself, the durability against abrasion and scratches due to rubbing, and the durability against active substances such as ozone and NOx are sufficient. However, at present, a protective layer having satisfactory electrophotographic properties has not yet been obtained as a protective layer corresponding to high image quality in recent years.

Further, with the recent increase in durability and image quality of photoconductors, a new problem has been pointed out as a photoreceptor pause memory phenomenon. The pause memory phenomenon is basically one of the deterioration phenomena due to corona products, but the rotation of the photoreceptor stops after copying is completed, and the charging ability of the portion stopped near the corona charger decreases, In the case of normal development, the image density decreases only in that portion, and in the case of reversal development, the image density increases. This phenomenon is likely to occur after the photoconductor has been used for a long time, and has become a more serious problem as the life of the photoconductor is extended.

In addition, in a reversal development system corresponding to recent digitization, since the primary charging and the transfer charging have opposite polarities, a so-called transfer memory having a different charging property depending on the presence or absence of transfer occurs, resulting in uneven density on an image. It is very easy to appear.

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to provide a photoconductor for electrophotography which meets the above-mentioned requirements.

That is, first, the object of the present invention is to provide a surface layer having excellent releasability, excellent durability against abrasion and generation of scratches, etc., and high quality image quality. An object of the present invention is to provide an electrophotographic photosensitive member that can be maintained.

A second object of the present invention is to provide an electrophotographic photoreceptor which does not cause a decrease in surface resistance due to adhesion of an active substance due to repeated use and can maintain high quality image even under high humidity. .

A third object of the present invention is to provide an electrophotographic photoreceptor which exhibits stable electrophotographic characteristics in which accumulation of residual potential and reduction in sensitivity do not easily occur even when used repeatedly.

A fourth object of the present invention is to provide an electrophotographic photoreceptor in which transfer memory hardly occurs even in a reversal developing system.

Fifth, it is an object of the present invention to provide an electrophotographic photosensitive member which does not cause a pause memory phenomenon.

Sixth, it is an object of the present invention to provide an electrophotographic apparatus and an apparatus unit having the above-described electrophotographic photosensitive member.

[0020]

That is, the present invention relates to an electrophotographic photosensitive member having a photosensitive layer and a protective layer on a conductive support, wherein the protective layer is a fluorine-containing silane coupling agent.
Select from the group consisting of and fluorine-modified silicone oil
An electrophotographic photoreceptor comprising conductive particles, a fluorine atom-containing resin particle, and a binder resin surface-treated with a fluorine atom-containing compound to be treated.

Further, the present invention is an electrophotographic apparatus and an apparatus unit having the above electrophotographic photosensitive member.

The conductive particles used in the present invention include metals, metal oxides and carbon black. Metals include aluminum, zinc, copper, chrome,
Examples thereof include nickel, stainless steel, silver, and the like, and those obtained by vapor-depositing these metals on the surfaces of plastic particles. As metal oxides, zinc oxide, titanium oxide,
Examples include tin oxide, antimony oxide, indium oxide, bismuth oxide, tin-doped indium oxide, antimony-doped tin oxide, and antimony-doped zirconium oxide. These can be used alone or in combination of two or more. 2
When using more than one kind in combination,
It may be in the form of a solid solution or fusion.

The average particle size of the conductive particles used in the present invention is preferably 0.3 μm or less, particularly preferably 0.1 μm or less, in view of the transparency of the protective layer.

In the present invention, among the above-described conductive particles, it is particularly preferable to use a metal oxide from the viewpoint of transparency and the like.

The fluorine atom-containing resin particles used in the present invention include ethylene tetrafluoride resin, ethylene trifluoride resin, ethylene hexafluoride propylene resin, vinyl fluoride resin, vinylidene fluoride resin, and dichloride difluoride. One or two of ethylene resins and their copolymers
It is preferable to appropriately select at least one kind, but particularly preferable are tetrafluoroethylene resin and vinylidene fluoride resin. The molecular weight of the resin particles and the particle size of the particles can be appropriately selected and are not particularly limited.

In the present invention, the surface of the conductive particles is treated with a fluorine atom-containing compound so that both the conductive particles and the fluorine atom-containing resin particles are not aggregated in a resin solution. By performing surface treatment,
The dispersibility and the dispersion stability of the conductive particles and the fluorine atom-containing resin particles in the resin solution were remarkably improved as compared with the case where the surface treatment was not performed. Further, by dispersing the conductive particles and the fluorine atom-containing resin particles subjected to the surface treatment with the fluorine atom-containing compound in a binder resin dissolved in a solvent, secondary particles of the dispersed particles are not formed, and the Thus, a very stable coating liquid having good dispersibility was obtained.

In the present invention, when the conductive particles are subjected to a surface treatment with a fluorine atom-containing compound, examples of the fluorine atom-containing compound that can be used include a fluorine-containing silane coupling agent and a fluorine-modified silicone oil. Hereinafter, each preferred compound is exemplified,
It is not limited to these compounds.

Preferred examples of the fluorine-containing silane coupling agent include CF ₃ CH ₂ CH ₂ Si (OCH ₃ ).
_{3, C 4 F 9 CH 2} CH 2 Si (OCH 3) 3, C 6 F
₁₃ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , C ₈ F ₁₇ CH ₂ C
H ₂ Si (OCH ₃ ) ₃ , C ₈ F ₁₇ CH ₂ CH ₂ Si
(OCH ₂ CH ₂ OCH ₃ ) ₃ , C ₁₀ F ₂₁ Si (OCH
₃ ) ₃ , C ₆ F ₁₃ CONHSi (OCH ₃ ) ₃ , C ₈ F
₁₇ CONHSi (OCH ₃ ) ₃ , C ₇ F ₁₅ CONHCH
₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , C ₇ F ₁₅ CONH
CH ₂ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ , C ₇ F ₁₅ C
OOCH ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , C ₇ F ₁₅
COSCH ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ , C ₈ F
₁₇ SO ₂ NHCH ₂ CH ₂ CH ₂ Si (OC ₂ H ₅ )
₃ ,

[0029]

[Outside 1] C ₈ F ₁₇ CH ₂ CH ₂ SCH ₂ CH ₂ Si (OCH ₃ )
₃ , C ₁₀ F ₂₁ CH ₂ CH ₂ SCH ₂ CH ₂ Si (OCH
₃ ) ₃ ,

[0030]

[Outside 2]

[0031]

[Outside 3] And the like.

Preferred examples of the fluorine-modified silicone oil include:

[0033]

[Outside 4] Is mentioned. Here, R in the formula is -CH ₂ CH ₂ CF ₃
And m and n are positive integers.

[0034]

[0035]

[0036]

[0037]

[0038]

The method for treating the surface of the conductive particles is as follows. First, the conductive particles and the surface treating agent are mixed and dispersed in an appropriate solvent, and the surface treating agent is attached to the surface of the conductive particles. As a dispersing means, ordinary dispersing means such as a ball mill and a sand mill can be used. Next, the solvent may be removed from the dispersion solution to fix the surface treating agent on the surface of the conductive particles. Further, if necessary, heat treatment may be performed thereafter. Further, a catalyst for promoting the reaction may be added to the treatment liquid. Further, the conductive particles after the surface treatment may be further subjected to a pulverizing treatment, if necessary.

The ratio of the fluorine-containing compound to the conductive particles is affected by the particle size of the particles, but is preferably 1 to 65% by weight based on the total weight of the surface-treated conductive particles. Preferably it is 10 to 50% by weight.

The binder resin that can be used in the protective layer of the present invention includes polycarbonate resin, polyester resin, polyarylate resin, polystyrene resin, polyethylene resin, polypropylene resin, polyurethane resin, acrylic resin, epoxy resin, silicone resin, Examples include cellulose resin, polyvinyl chloride resin, phosphazene resin, melamine resin, and vinyl chloride-vinyl acetate copolymer. These resins can be used alone or in combination of two or more.

Among the above resins, it is preferable to use a curable resin in view of the surface hardness of the protective layer, the abrasion resistance, the dispersibility of the fine particles and the stability after dispersion. That is, the above-described conductive particles and fluorine atom-containing resin particles are dispersed in a solution containing a monomer or oligomer which is cured by heat or light to form a coating solution for a protective layer, and the solution is coated on a photosensitive layer. The protective layer formed by curing is more preferable in terms of dispersibility, hardness and abrasion resistance.

The monomer or oligomer which is cured by heat or light has, for example, a functional group which causes a polymerization reaction at the end of the molecule by the energy of heat or light. Are relatively large oligomers and smaller ones are monomers. Examples of the functional group that causes the polymerization reaction include acryloyl group, methacryloyl group, a group having a carbon-carbon double bond such as a vinyl group, a silanol group, and a compound that causes ring-opening polymerization such as a cyclic ether group, or a phenol and formaldehyde. As described above, there are those in which two or more kinds of molecules react to cause polymerization.

The ratio of the conductive metal oxide particles in the protective layer is one of the factors directly determining the resistance of the protective layer, and the resistance of the protective layer is in the range of 10 ¹⁰ to 10 ¹⁵ _{ohm · cm} . Preferably, there is.

The proportion of the fluorine atom-containing resin particles in the protective layer is preferably from 5 to 70% by weight, more preferably from 10 to 60% by weight, based on the total weight of the protective layer. When the proportion of the fluorine atom-containing resin particles is more than 70% by weight, the mechanical strength of the protective layer tends to decrease, and when the proportion of the fluorine atom-containing resin particles is less than 5% by weight, the releasability of the protective layer surface and the protective layer Abrasion resistance and scratch resistance may not be sufficient.

In the present invention, additives such as a radical scavenger and an antioxidant may be added to the protective layer for the purpose of further improving the dispersibility, the binding property and the weather resistance.

The thickness of the protective layer of the present invention is 0.2 to 10 μm.
Is more preferable, and more preferably in the range of 0.5 to 6 μm.

Next, the photosensitive layer will be described. The structure of the photosensitive layer of the electrophotographic photoreceptor of the present invention may be a single layer containing both a charge generating substance and a charge transporting substance in the same layer, or a charge generating layer and a charge transporting layer laminated on a conductive support. One of the stacked type. Hereinafter, the laminated photosensitive layer will be described.

The structure of the laminated photosensitive layer includes a structure in which a charge generation layer and a charge transport layer are laminated on a conductive support in this order, and a structure in which a charge transport layer and a charge generation layer are laminated in this order. .

The conductive support used in the present invention may be any one as long as it has conductivity. For example, a metal such as aluminum, copper, chromium, nickel, zinc, stainless steel or the like is formed into a drum or sheet. A metal foil such as aluminum or copper laminated on a plastic film, aluminum, indium oxide, tin oxide or the like deposited on a plastic film, a conductive material applied alone or with a binder resin to form a conductive layer Metal, plastic film, paper and the like can be mentioned.

The charge transport layer of the laminated photoreceptor is formed by using a coating solution in which a charge transport material such as a pyrazoline compound, a hydrazone compound, a styryl compound, and a triarylamine compound is dissolved in a resin having a film forming property. .

Examples of the resin having such a film forming property include polyester, polycarbonate, polystyrene and polymethacrylate. The thickness of the charge transport layer is 5 to 40 μm, preferably 10 to 30 μm.

The charge generating layer of the laminated photoreceptor is made of an azo pigment such as Sudan Red or Diane Blue; a quinone pigment such as pyrenequinone or anthantrone; a quinocyanine pigment; a perylene pigment; an indigo pigment such as indigo or thioindigo; The charge generating substance is dispersed in a binder resin such as polyvinyl butyral, polystyrene, polyvinyl acetate and an acrylic resin,
The dispersion is applied or the pigment is formed by vacuum evaporation. The thickness of such a charge generation layer is 5
μm or less, preferably 0.05 to 3 μm.

In the present invention, in order to further improve the adhesiveness between the photosensitive layer and the protective layer, 0.1-0.1
An intermediate layer having a thickness of about 5 μm can be provided.

In the present invention, an undercoat layer having a barrier function and an adhesive function may be provided between the conductive support and the photosensitive layer. The undercoat layer can be formed of casein, polyvinyl alcohol, nitrocellulose, ethylene-acrylic acid copolymer, alcohol-soluble amide, polyurethane, gelatin and the like. The thickness of the undercoat layer is 0.1
μm to 0.3 μm is preferred.

The electrophotographic photoreceptor of the present invention can be applied not only to electrophotographic apparatuses such as copying machines, laser printers, LED printers, and liquid crystal shutter printers in general, but also to displays, recording,
The present invention can be widely applied to devices such as light printing, plate making, and facsimile.

FIG. 1 shows a schematic configuration of an electrophotographic apparatus using the electrophotographic photosensitive member of the present invention.

Referring to FIG. 1, reference numeral 1 denotes a drum type photosensitive member of the present invention, which is driven to rotate around an axis 1a at a predetermined peripheral speed in a direction indicated by an arrow. The photoreceptor 1 is uniformly charged with a predetermined positive or negative potential on its peripheral surface by a charging means 2 during the rotation process, and then, in an exposure section 3, a light image exposure L (slit exposure) by an image exposure means (not shown).・ Laser beam scanning exposure etc.)
Receive. As a result, an electrostatic latent image corresponding to the exposure image is sequentially formed on the peripheral surface of the photoconductor.

The electrostatic latent image is then developed with toner by developing means 4, and the developed toner image is synchronized between the photosensitive member 1 and the transfer means 5 between the photosensitive member 1 and the transfer means 5 from a paper feeding unit (not shown). The transfer material 5 is sequentially transferred to the transferred and fed transfer material P.

The transfer material P having undergone the image transfer is separated from the photoreceptor surface, introduced into the image fixing means 8 and subjected to image fixing to be printed out as a copy (copy) outside the machine.

The surface of the photoreceptor 1 after the image transfer is cleaned and cleaned by removing the untransferred toner by the cleaning means 6, and is further subjected to a static elimination treatment by the pre-exposure means 7 to be repeatedly used for image formation. You.

As the uniform charging means 2 for the photoreceptor 1, a corona charging device is generally widely used. Transfer device 5
Also, corona transfer means are generally widely used. In the present invention, a plurality of components such as the photoreceptor, the developing unit and the cleaning unit are integrally connected as an apparatus unit, and the unit is detachably attached to the apparatus body. May be. For example, a unit is formed by integrally supporting at least one of the charging unit, the developing unit, and the cleaning unit together with the photoreceptor, and a unit is detachably attached to the apparatus main body. It may be configured to be detachable.
At this time, the above-described device unit may be provided with a charging unit and / or a developing unit.

In the case where the electrophotographic apparatus is used as a copier or a printer, the light image exposure L involves irradiating the photosensitive member with reflected light or transmitted light from the original, or reading the original with a sensor and converting it into a signal. In accordance with this signal, scanning of a laser beam, driving of an LED array, driving of a liquid crystal shutter array, and the like are performed to irradiate the photosensitive member with light.

When used as a facsimile printer, the light image exposure L is an exposure for printing received data. The figure shows an example of this case in a block diagram.

The controller 11 controls the image reading unit 10 and the printer 19. The whole controller 11 is CP
It is controlled by U17. The read data from the image reading unit is transmitted to the partner station through the transmission circuit 13. Data received from the partner station is sent to the printer 19 through the receiving circuit 12. Predetermined image data is stored in the image memory. The printer controller 18 controls a printer 19. 14 is a telephone.

The image received from the line 15 (image information from a remote terminal connected via the circuit) is demodulated by the receiving circuit 12, and then the CPU 17 performs a decoding process on the image information and sequentially processes the image memory 16 Is stored in And
When the image of at least one page is stored in the memory 16, the image of the page is recorded. The CPU 17 reads out one page of image information from the memory 16 and sends out the decoded one page of image information to the printer controller 18. Upon receiving one page of image information from the CPU 17, the printer controller 18 controls the printer 19 to record image information of the page.

The CPU 17 receives the next page during recording by the printer 19.

As described above, image reception and recording are performed.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

[0070]

【Example】

(Example 1) On an aluminum cylinder, 10 parts (parts by weight, hereinafter the same) of an alcohol-soluble polyamide resin (Amilan CM-8000, manufactured by Toray Industries, Inc.) and a methoxymethylated 6 nylon resin (Toresin EF-30T, Teikoku) A solution prepared by dissolving 30 parts in a mixed solvent of 150 parts of methanol and 150 parts of butanol was dip-coated and dried at 90 ° C. for 10 minutes to form an undercoat layer having a thickness of 1 μm. did.

Next, the following equation

[0072]

[Outside 9] Is added to a solution obtained by dispersing 4 parts of a disazo pigment represented by the following formula, 2 parts of a butyral resin (ESREC BL-S, manufactured by Sekisui Chemical Co., Ltd.) and 100 parts of cyclohexanone for 48 hours using a sand mill device, and 100 parts of tetrahydrofuran (THF). Thus, a dispersion for a charge generation layer was obtained. This dispersion was applied onto the undercoat layer by dip coating and dried at 80 ° C. for 15 minutes to form a charge generation layer having a thickness of 0.15 μm.

Next, the following equation

[0074]

[Outside 10] A solution prepared by dissolving 10 parts of a triarylamine compound represented by the following formula and 10 parts of a polycarbonate resin (Iupilon Z-200, manufactured by Mitsubishi Gas Chemical Co., Ltd.) in a mixed solvent of 20 parts of dichloromethane and 50 parts of monochlorobenzene is described above. The charge transport layer having a film thickness of 20 μm was formed by dip coating on the generating layer and drying at 120 ° C. for 60 minutes.

Next, a dispersion liquid for a protective layer was prepared according to the following procedure.

Antimony-containing tin oxide fine particles having an average particle size of 0.02 μm (T-1, manufactured by Mitsubishi Materials Corporation)
A solution obtained by milling 00 parts, 30 parts of (3,3,3-trifluoropropyl) trimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.), and 300 parts of a 95% ethanol-5% aqueous solution with a milling machine for 1 hour was filtered. After washing with ethanol and drying, the particles were subjected to a heat treatment at 120 ° C. for 1 hour to perform a surface treatment of the fine particles.

Next, the following formula as a binder resin

[0078]

[Outside 11] , 25 parts of an acrylic curable monomer, 0.1 part of 2-methylthioxanthone as a photopolymerization initiator, 35 parts of antimony-containing tin oxide fine particles subjected to the surface treatment, and 300 parts of toluene were mixed with a sand mill. 9
25 parts of tetrafluoroethylene resin particles (Rublon L-2, manufactured by Daikin Industries, Ltd.) were mixed with the dispersion dispersed for 6 hours, and the mixture was further dispersed for 8 hours by a sand mill to obtain a dispersion for a protective layer.

This dispersion was spray-coated on the charge transport layer, dried, and irradiated with ultraviolet light at a light intensity of 800 mW / cm ² for 15 seconds using a high-pressure mercury lamp to form a film having a thickness of 5 μm.
m of protective layers were formed.

Example 2 The amount of the tetrafluoroethylene resin particles in the dispersion for the protective layer used in Example 1 was 45 parts,
A photoconductor was prepared in the same manner as in Example 1, except that the amount of the surface-treated antimony-containing tin oxide fine particles was changed to 45 parts.

(Example 3) Instead of the acrylic curable monomer of the preparation liquid for the protective layer used in Example 1, the following structural formula was used.

[0082]

[Outside 12] A photoreceptor was prepared in the same manner as in Example 1 except that an acrylic curable monomer represented by the following formula was used.

Example 4 A photoconductor was prepared in the same manner as in Example 1, except that the dispersion for the protective layer used in Example 1 was changed as follows.

Antimony-containing tin oxide fine particles having an average particle size of 0.02 μm (T-1, manufactured by Mitsubishi Materials Corporation) 1
00 parts, fluorine-modified silicone oil (FL-100,
A solution obtained by milling 30 parts of 300 parts of toluene and 300 parts of toluene with a milling apparatus for 1 hour, washing with toluene, drying, and heating at 300 ° C. for 10 minutes to obtain a fine particle surface. Processing was performed. Next, the following formula as a binder resin

[0085]

[Outside 13] , 25 parts of an acrylic curable monomer, 0.1 part of 2-methylthioxanthone as a photopolymerization initiator, 50 parts of the surface-treated antimony-containing tin oxide fine particles and 300 parts of toluene were mixed with a sand mill. 9
35 parts of tetrafluoroethylene resin particles (Rublon L-2, manufactured by Daikin Industries, Ltd.) were mixed with the dispersion dispersed for 6 hours, and the mixture was further dispersed by a sand mill for 4 hours to obtain a dispersion for a protective layer.

Example 5 The procedure was performed except that ethylene trifluoride chloride resin particles (DAIFRON, manufactured by Daikin Industries) were used instead of the ethylene tetrafluoride resin particles of the dispersion for the protective layer used in Example 1. A photoconductor was prepared in the same manner as in Example 1.

(Example 6) In place of the antimony-containing tin oxide fine particles used in Example 1, barium sulfate fine particles were coated with oxygen-deficient tin oxide, and conductive particles having an average particle diameter of 0.1 µm (Pastran IV / P- 1, a photoreceptor was prepared in the same manner as in Example 1 except that Mitsui Kinzoku Mining Co., Ltd. was used.

Example 7 A photoconductor for positive charging was prepared in the same manner as in Example 1 except that the charge generation layer and the charge transport layer were stacked in reverse order.

Example 8 A photoconductor was prepared in the same manner as in Example 1, except that an intermediate layer formed by the following method was provided between the charge transport layer and the protective layer used in Example 1.

A ligroin solution of a silicone resin (AY42-441, manufactured by Toray Silicone Co., Ltd.) was spray-coated so that the film thickness after drying was 0.2 μm.

The electrophotographic photosensitive members of Examples 1 to 8 prepared as described above were mounted on a copying machine in which a charge-exposure-development-transfer-cleaning process was repeated in a cycle of 1.5 seconds. % Under normal temperature and normal humidity (N / N),
10 ° C., 15% low temperature and low humidity (L / L), and 35%
The image was evaluated under high temperature and high humidity (H / H) of 85 ° C. and 85%, and a repetitive image output durability test of 50,000 sheets was performed under normal temperature and normal humidity. As a result, compared to the photoreceptor shown in a comparative example described later, an image free of unevenness and black spots due to burrs and the like could be obtained. Moreover, even in a repetitive image output durability test of 50,000 sheets, stable and good images without fusing or filming could be maintained, and the durability against abrasion and scratches on the surface was remarkably improved. Table 1 shows the results. The dark part potential is corona discharge voltage −5 KV (however, in the case of the seventh embodiment, +
The surface potential of the photoconductor when it is discharged at 5 KV), and the larger the value, the better the charging ability. The sensitivity is represented by an exposure amount required to attenuate the surface potential from 700 V to 200 V in absolute value.

Further, in order to measure the pause memory phenomenon,
The above-mentioned photoconductor was attached to a modified copy machine of Canon NP-3825, and the dark portion potential (V _D ) and the light portion potential (V
_L ) were set to a latent image condition of -650 V and -150 V, respectively. Next, the potential after the continuous copying of 10,000 sheets was measured, and the rate of change of V _D and V _L was determined (for example, a rate of change of 2% in V _D means 650)
2% of V, that is, a change of 13V). Thereafter, the photoreceptor was left in the copying machine, and after 24 hours, the difference (ΔV _D ) between the absolute value of the surface potential of the photoreceptor located immediately below the corona charger and the potential of other portions was measured. Table 1 shows the results.

(Examples 9 to 16) Next, in order to evaluate the transfer memory, photosensitive drums in which the charge generation layers of Examples 1 to 8 were changed as follows were prepared (undercoat layer, charge The transport layer and the protective layer were formed in the same manner as in Examples 1 to 8.

Oxytitanium phthalocyanine 4.5
Part of butyral resin (ESREC BL-S, manufactured by Sekisui Chemical Co., Ltd.) and 100 parts of cyclohexanone dispersed in a sand mill for 36 hours, and 100 parts of tetrahydrofuran was added to the resulting solution to prepare a dispersion for the charge generation layer. I got This dispersion is dip-coated on the undercoat layer,
After drying at 15 ° C. for 15 minutes, a charge generation layer having a thickness of 0.15 μm was formed. (The photoreceptors of Examples 9 to 16 correspond in order to the photoreceptors having different charge generation layers of Examples 1 to 8.) The photoreceptors of Examples 9 to 16 were replaced with a reversal developing type electronic device equipped with a semiconductor laser. The photoreceptor is mounted on a laser beam printer (a modified LBP-SX made by Canon) which is a photographic printer, and the primary charging voltage when the transfer current is OFF is V _dl , and the primary charging voltage when the transfer current is ON is V _d2. ,
The so-called transfer memory | V _d1 | − | V _d2 | was measured.
Table 2 shows the results.

Comparative Example 1 A photoconductor was prepared in the same manner as in Example 1 except that the protective layer was not provided, and the same evaluation was performed.

As a result, as shown in Table 1, the initial electrophotographic characteristics were good. However, when the device was durable, the charging ability was lowered, and a good image could not be obtained from about 10,000 sheets.

Comparative Example 2 Example 1 was repeated except that no fluorine atom-containing resin particles were dispersed in the protective layer.
A photoreceptor was prepared and evaluated in the same manner as described above.

As a result, as shown in Table 1, from the beginning, the image was in the shape of a relief. Further, under high temperature and high humidity, image blur was generated, and further image blur was observed due to durability.

Comparative Example 3 A photoconductor was prepared in the same manner as in Example 1 except that the surface treatment of the conductive fine particles used in the protective layer was not performed, and the same evaluation was performed.

As a result, as shown in Table 1, the initial electrophotographic characteristics were good, but the charging ability was reduced after the durability test, and good images could not be obtained from around 35,000 sheets.

Comparative Example 4 A photoconductor was prepared in the same manner as in Example 7 except that the protective layer was not provided, and the same evaluation was performed.

As a result, as shown in Table 1, under high temperature and high humidity, image blur occurs, and after about 10,000 sheets, the sensitivity is remarkably reduced due to abrasion of the charge generation layer, and the image contrast is lost and good image quality is obtained. I can no longer get images.

Table 1 shows the measurement results of the pause memory phenomenon in Comparative Examples 1 to 4. In all cases, the potential fluctuation under the charger was extremely large as compared with the examples.

Comparative Example 5 A photoconductor was prepared in the same manner as in Example 9 except that the protective layer was not provided, and the same evaluation was performed. Table 2 shows the results.

Comparative Example 6 Example 9 was repeated except that no fluorine atom-containing resin particles were dispersed in the protective layer in Example 9.
A photosensitive member was prepared in the same manner as described above, and the same evaluation was performed.
Table 2 shows the results.

Comparative Example 7 A photoconductor was prepared in the same manner as in Example 9 except that the surface treatment of the conductive fine particles used in the protective layer was not performed, and the same evaluation was performed. Table 2 shows the results.

Comparative Example 8 A photoconductor was prepared in the same manner as in Example 14 except that the surface treatment of the conductive fine particles used in the protective layer was not performed, and the same evaluation was performed. Table 2 shows the results.

(Comparative Example 9) A photoconductor was prepared in the same manner as in Example 15 except that the protective layer was not provided, and the same evaluation was performed. Table 2 shows the results.

[0109]

[Table 1]

[0110]

[Table 2]

[0111]

As described above, the electrophotographic photoreceptor of the present invention has excellent electrophotographic characteristics with almost no decrease in sensitivity and no increase in residual potential.

Further, since the protective layer is extremely excellent in surface releasability, abrasion resistance and environmental stability, a stable image with good image quality can be provided even when used repeatedly.

Further, it is possible to provide an electrophotographic photosensitive member which is extremely excellent in terms of a rest memory and a transfer memory.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a schematic configuration of an electrophotographic apparatus having an electrophotographic photosensitive member of the present invention.

FIG. 2 is a diagram illustrating an example of a block diagram of a facsimile having the electrophotographic photosensitive member of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrophotographic photoreceptor 1a shaft 2 Charging means 3 Exposure part 4 Developing means 5 Transfer device 6 Cleaning means 7 Pre-exposure means 8 Image fixing means L Light image exposure P Transfer material

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Michiyo Sekiya 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-4-328570 (JP, A) JP-A-1 -306857 (JP, A) JP-A-2-50167 (JP, A) JP-A-64-35448 (JP, A) JP-A-1-169461 (JP, A) JP-A-62-206559 (JP, A) JP-A-2-201450 (JP, A) JP-A-4-310958 (JP, A) JP-A-63-73267 (JP, A) JP-A-53-116156 (JP, A) 69100 (JP, A) JP-A-56-47042 (JP, A) JP-A-60-115944 (JP, A) JP-A-5-181299 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 5/147

Claims (4)

(57) [Claims] 1. An electrophotographic photosensitive member having a photosensitive layer and a protective layer on a conductive support, wherein the protective layer is a fluorine-containing material.
Silane coupling agent and fluorine-modified silicone oil
An electrophotographic photoreceptor comprising conductive particles surface-treated with a fluorine atom-containing compound selected from the group consisting of 2. The electrophotographic photoreceptor according to claim 1, wherein said fluorine atom-containing resin particles are selected from the group consisting of ethylene tetrafluoride resin particles and vinylidene fluoride resin particles. And means for transferring electrophotographic photosensitive member according, means for forming an electrostatic latent image, means for developing the formed electrostatic latent image and the developed image to the transfer material to 3. A process according to claim 1 or 2 An electrophotographic apparatus, characterized in that: 4. An electrophotographic photoreceptor according to claim 1 or 2 , and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means, which are integrally supported and detachably attached to the apparatus main body. An apparatus unit, characterized in that: