JP2003186218A - Electrophotographic photoreceptor and process cartridge and electrophotographic device having that electrophotographic photoreceptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor having high durability, high sensitivity and no accumulation of residual potential in repeated electrophotographic processes and keeping high picture quality without causing changes in the characteristics by the use environment and to provide a process cartridge and an electrophotographic device having the above electrophotographic photoreceptor. <P>SOLUTION: In the electrophotographic photoreceptor having a photosensitive layer and a protective layer on a conductive supporting body, the photosensitive layer contains at least one kind of phthalocyanine having a silicon atom in the center as a charge generating material. The protective layer is a film formed by three-dimensionally crosslinking. The process cartridge and the electrophotographic photoreceptor have the above electrophotographic photoreceptor. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic photosensitive member, a process cartridge having the electrophotographic photosensitive member, and an electrophotographic apparatus.

[0002]

2. Description of the Related Art Conventionally, selenium has been used as an electrophotographic photoreceptor.
Inorganic photoreceptors having a photosensitive layer containing zinc oxide, cadmium and the like as main components have been widely used. Although these have some basic characteristics, they have problems such as poor film forming property, poor plasticity, and high manufacturing cost. Further, the inorganic photoconductive material is generally highly toxic, and there are great restrictions in manufacturing and handling. On the other hand, an organic photoconductor containing an organic photoconductive compound as a main component has attracted attention in recent years because it has many advantages such as compensating the above-mentioned drawbacks of the inorganic photoconductor, and many proposals have been made so far and some of them have been put into practical use. Has been done. As such an organic photoconductor, a function-separated electrophotographic photoconductor in which a charge generation function and a charge transport function are shared by different substances has been widely used. Such a function-separated type photoconductor has the advantage that the material selection range of each of the charge generation material and the charge transport material is wide, and that an electrophotographic photoconductor having arbitrary characteristics can be prepared relatively easily. As charge generation materials, cyanine dyes, squaric acid dyes, azurenium salt dyes, pyrylium salt dyes, azo pigments and polycyclic quinone pigments,
On the other hand, it is known that a pyrazoline compound, a hydrazone compound, a triphenylamine compound, a stilbene compound, or the like is used as a charge transport material to have excellent electrophotographic properties.

As a matter of course, the electrophotographic photosensitive member is required to have the required sensitivity, electrical characteristics and optical characteristics according to the electrophotographic process to be applied. Particularly in the case of a repeatedly used photoconductor, electrical and mechanical external forces such as charging, image exposure, toner development, transfer to paper and cleaning are directly applied to the surface of the photoconductor, so durability against them Is required. Specifically, it is required to have durability against abrasion and scratches on the surface of the photoconductor caused by rubbing of the surface of the photoconductor during transfer, cleaning, etc., and deterioration of the photoconductor and potential characteristics due to ozone and charge products generated during charging. It

In order to satisfy the above-mentioned characteristics required for the photoreceptor, attempts have been made to provide a surface layer containing a resin as a main component on the photosensitive layer. For example, JP-A-56-428
In JP-A-63-63, JP-A-53-103741, and the like, it is proposed to improve the hardness and wear resistance of the surface of the photoconductor by using a protective layer containing a curable resin as a main component.

Further, in order to obtain a better image, the protective layer of the photoconductor has not only characteristics such as high hardness and excellent abrasion resistance, but also electric charges are transferred inside the surface layer, so that the photosensitive layer is protected. It is required to cancel the electric charge inside and the electric charge due to charging. Although the three-dimensionally crosslinked resin has a high hardness, since it is generally an electrical insulator, the resistance of forming the protective layer only with the resin is too high, and by repeating the electrophotographic process such as charging-exposure, Charges are accumulated in the surface protective layer, so-called residual potential increases, and the potential is not stable when the photoconductor is repeatedly used, and the image quality becomes unstable. In particular, this phenomenon becomes more remarkable as the thickness of the surface layer increases, so the thickness of the surface layer must be made extremely small, and it is difficult to significantly extend the life of the electrophotographic photosensitive member. In order to improve this problem, for example, in Japanese Patent Laid-Open No. 63-212771, an attempt is made to transfer electric charges in the surface layer by dispersing conductive fine particles or a charge transport material in the thermosetting resin in the surface layer. ing. However, when the resistance of the surface layer is adjusted by the conductive particles, even if the curable resin is selected as the binder resin of the surface layer, the conductive material such as the metal oxide fine particles is used in the surface layer. Since the discontinuity of the chemical bond occurs, it is difficult to obtain sufficient mechanical strength. Even in a surface protective layer containing a charge transport material without using a conductive material, the charge transport material itself often inhibits the curing reaction of the surface layer, so that it is difficult to obtain sufficient mechanical strength. there were.

When a curable resin is used as a binder resin for a surface layer containing a conductive material or a charge transport material, it is effective to increase the curing conditions in order to impart sufficient strength to the surface layer. . For example, when a thermosetting resin is selected as the binder resin for the surface layer, it is effective to raise the curing temperature or extend the heating time. However, the heat resistance of the photoconductor material is generally low, and in particular, the charge generation material undergoes a cross-linking reaction of the thermosetting resin due to various factors such as a change in crystal structure, a decrease in crystal water, and an interaction with the charge transport material. When the heat treatment is carried out to sufficiently accelerate the above, the electrophotographic characteristics of the photosensitive member are remarkably deteriorated, and the residual potential is increased and the sensitivity is decreased. In particular, a dye-based charge generation material having an ionic salt structure can shift the absorption wavelength to the long wavelength side relatively easily, but has a property that the characteristics change remarkably due to thermal history.

For example, when an ultraviolet curable resin is selected as the binder resin for the surface layer, it is effective to increase the intensity of irradiation light or extend irradiation time. However, the charge generating material has strong light absorption, and when it is irradiated with strong light energy, various deterioration reactions such as breaking and substitution of a part of the molecular bond occur, and the crosslinking reaction of the UV curable resin is sufficiently performed. When the UV irradiation is advanced to such an extent that the electrophotographic characteristics of the photoconductor are significantly deteriorated, the residual potential is increased and the sensitivity is decreased. In recent years, many azo compounds have been put to practical use as charge generation materials in organic photosensitive layers, but it is generally known that azo compound dyes have weak azo bond strength to light and poor fading properties. Phthalocyanine compounds such as copper phthalocyanine are said to be more stable to light than azo compounds, but when used as a charge generation material, sensitivity and potential stability, and when a curable resin is used as a binder resin for the surface layer. When used, no one having satisfactory properties in terms of stability during curing reaction was found.

Therefore, in producing an electrophotographic photosensitive member having a surface strength capable of withstanding various electrophotographic processes,
There is a strong demand to develop a charge generation material that does not deteriorate even when the surface layer is hardened sufficiently.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to maintain high image quality with high durability, high sensitivity, no accumulation of residual potential in repeated electrophotographic processes, and no change in characteristics due to use environment. It is also an object of the present invention to provide a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

[0010]

The present invention provides an electrophotographic photoreceptor having a photosensitive layer and a protective layer on a conductive support, the photosensitive layer containing at least phthalocyanine having a silicon atom at the center as a charge generating material. An electrophotographic photoreceptor comprising one kind of the protective layer, which is a layer formed by three-dimensionally crosslinking.

Hereinafter, "protective layer" is referred to as "surface protective layer".
Also called.

When the protective layer having the above structure is provided, deterioration of the charge generating material does not occur even if the conditions of the crosslinking reaction are strengthened so as to have desired hardness of the protective layer, so that the residual potential is increased and the sensitivity is lowered. Does not occur.

Further, the present invention is the above electrophotographic photoreceptor, wherein the protective layer contains metal fine particles or metal oxide fine particles as a charge transport material and / or a conductive material.

With this structure, the charge in the photosensitive layer and the charge on the surface of the electrophotographic photosensitive member in the electrophotographic process can be offset without any delay, so that the electrophotographic characteristics are not impaired.

Further, the present invention is the above electrophotographic photoreceptor, wherein the surface protective layer contains conductive fine particles and at least one of a fluorine atom-containing compound and a siloxane compound.

With this structure, the conductive fine particles are stably dispersed in the surface protective layer coating material and the surface protective layer film without agglomerating, and have sufficient light transmittance and resistance stability of the surface protective layer. It becomes possible.

Further, the present invention is a process cartridge and an electrophotographic apparatus having the above electrophotographic photosensitive member.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The conductive support used in the present invention may be any one as long as it has conductivity.
For example, aluminum, chrome, nickel, stainless steel,
Metals and alloys such as copper and zinc, metal foils such as aluminum and copper laminated on plastic films, aluminum, indium oxide, tin oxide, etc. deposited on plastic films, or conductive substances alone or appropriate Examples thereof include metals, plastic films and paper coated with a binder resin to provide a conductive layer.

As the conductive substance used in this conductive layer, metal powder such as aluminum, copper, nickel and silver,
Metal foil and metal fiber, conductive metal oxide such as antimony oxide, indium oxide and tin oxide, polymer conductive material such as polypyrrole, polyaniline and polymer electrolyte, carbon black, graphite powder and organic or inorganic electrolyte, and Examples thereof include conductive powders whose surfaces are coated with these conductive substances.

The conductive support has a drum shape,
Examples thereof include a sheet shape and a belt shape, but it is preferable that the shape is an arbitrary shape most suitable for the applied electrophotographic apparatus.

An undercoat layer may be provided between the conductive support and the photosensitive layer. The undercoat layer functions as a barrier layer or an adhesive layer for controlling charge injection at the interface with the photosensitive layer. The undercoat layer is mainly composed of a binder resin, but may contain the above metal or alloy, or an oxide, salt or surfactant thereof.

As the binder resin forming the undercoat layer, polyester, polyurethane, polyacrylate, polyethylene, polystyrene, polybutadiene, polycarbonate, polyamide, polypropylene, polyimide, phenol resin, acrylic resin, silicone resin, epoxy resin, urea resin , Allyl resin, alkyd resin, polyamideimide, polysulfone, polyallyl ether, polyacetal and butyral resin. The thickness of the undercoat layer is preferably 0.05 to 7 μm, more preferably 0.1 to 2 μm.

As the constitution of the photosensitive layer in the present invention, a function-separated type photosensitive layer provided by laminating a charge generating layer and a charge transporting layer separately, a single layer containing a charge generating material and a charge transporting material in the photosensitive layer It is possible to take any form of photosensitive layer.

The charge generation layer in the present invention is formed as a uniform layer in which the charge generation material is formed by a method such as vapor deposition and sputtering, or a dispersion liquid in which the charge generation material is dispersed in a binder resin is applied, It is formed by drying.

As the charge generating material used for the photosensitive layer,
As a result of extensive studies on various materials, the phthalocyanine compound having a silicon atom at the center represented by the following general formula is not only excellent in electrophotographic characteristics such as sensitivity and residual potential, but also uses a curable resin for the surface layer. It has been found that even when an electrophotographic photosensitive member is produced by the above method, and even when the surface hardness is increased by increasing the conditions of the heat curing process and the ultraviolet irradiation process, the charge generation material is not significantly deteriorated.

[0026]

[Chemical 2] (In the formula, R ₁ and R ₂ may be the same or different and each represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or a halogenated alkyl group. X ₁ , X ₂ , X ₃ and X ₄ are the same. Or may be different, and represents a halogen atom, an alkyl group having 1 to 8 carbon atoms or a halogenated alkyl group, a, b, c and d may be the same or different and represent an integer of 0 to 4, n represents an integer of 0 or more.) In particular, among the silicon phthalocyanines represented by the general formula 1, the Bragg angle 2θ in CuKα characteristic X-ray diffraction is
(± 0.3 °) of 9.2, 14.1, 15.3, 19.
Dihydroxysilicon phthalocyanine compound having peaks at 7 and 27.1 ° (that is, n =
0), 6.9, 8.0, 10.6, 16.0, 26.3.
It has been found that the dimerized dihydroxysilicon phthalocyanine compound (that is, n = 1 in the above general formula) and the mixture of the dihydroxysilicon phthalocyanine compound and the dialkoxysilicon phthalocyanine compound have favorable characteristics.

As the binder resin, in the case of the function-separated type photosensitive layer, a conventionally used resin for the charge generation layer can be used. For example, polyvinyl butyral and polyvinyl formal or the like polyvinyl acetal resin, polystyrene, acrylic resin. , Cellulose ester, cellulose ether, polyester, polycarbonate, phenoxy resin, urethane resin and epoxy resin.

Further, the charge generation layer is, for example, 2, 4, 7
Electron-accepting substances such as trinitrofluorenone and tetracyanoquinodimethane, heterocyclic compounds such as carbazole, indole, imidazole, oxazole, pyrazole, oxadiazole, pyrazoline and thiadiazole, aniline derivatives, hydrazone compounds, aromatic amine derivatives Further, an electron donating substance such as a stilbene derivative or a polymer having a group composed of these compounds in the main chain or side chain may be added. In case of function separation type,
The thickness of the charge generation layer is preferably 10 μm or less, and particularly preferably 0.05 to 2 μm.

The charge-transporting layer in the present invention is formed by applying a coating solution prepared by dissolving a charge-transporting material having a film-forming property with a suitable solvent and drying it. Examples of the charge transport material in the photosensitive layer include carbazole and
A compound having a heterocyclic ring such as indole, imidazole, thiazole, oxadiazole, pyrazole and pyrazoline, an aniline derivative such as phenylamine, diphenylamine and triphenylamine, a hydrazone derivative, a stilbene derivative and a group consisting of these compounds in the main chain or Examples thereof include electron-donating substances such as polymers having a side chain. As the binder resin, a conventionally used resin for a charge transport layer can be used, and for example, polycarbonate, polyester, polyarylate, acrylic resin, styrene resin and the like can be used.

When the charge transport layer is used as the surface layer in the function-separated type photoreceptor or when the photosensitive layer is used as the surface layer in the single-layer photoreceptor, the binder resin is a thermosetting resin or an ultraviolet curable resin. A desired surface hardness can be obtained by using a resin.

The thickness of the charge transport layer in the case of the function-separated type and the thickness of the photosensitive layer in the case of a single-layer photoreceptor are preferably 5 to 40 μm, particularly preferably 10 to 30 μm.

In the present invention, when a surface layer is coated on the single-layer photoconductor or the function-separated photoconductor, a conductive material and / or a charge transfer agent is applied on the surface in order to prevent the movement of charges. It is preferably contained in the layer. Examples of the conductive material include metals, metal oxides, conductive polymers, carbon black and the like. Examples of the metal include aluminum, zinc, copper, chromium, nickel, stainless steel, silver, and the like, and those obtained by vapor-depositing these metals on the surface of plastic particles. Examples of the metal oxide include zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, tin-doped indium oxide, antimony-doped tin oxide and zirconium oxide. Examples of the conductive polymer include polyacetylene, polythiophene and polypyrrole. These may be used alone or in combination of two or more. When two or more kinds are used in combination, they may be simply mixed, or may be in the form of a solid solution or fusion.

The average particle size of the conductive material used in the present invention is 0.3 μm from the viewpoint of preventing light scattering.
It is preferably m or less, and particularly preferably 0.1 μm or less. Further, a metal oxide is more preferable in terms of transparency. In order to keep the strength of the protective layer strong, the incorporation of fine particles is not preferable, but if the protective layer itself does not have a certain degree of conductivity, a photoreceptor satisfying the electrophotographic characteristics cannot be obtained. It is preferable to include a conductive material so as to obtain the resistance value described.

Resistance of the surface layer of the present invention when a conductive material is contained in the surface layer: R is 10 ¹¹ <R ≦ 10 ¹⁵ Ω · c
It is preferably m. When the resistance is 10 ¹¹ Ω · cm or less, it becomes difficult to retain electric charges, and image deletion easily occurs. On the other hand, when the resistance exceeds 10 ¹⁵ Ω · cm, it becomes difficult for the charges to move, the residual potential rises, and the concentration becomes low and the negative ghost easily occurs. The resistance can be measured as follows. First, the distance between electrodes (D) 180
A surface layer of the present invention having a thickness (T) of 4 μm is provided on a comb-shaped platinum electrode having a thickness of μm and a length (L) of 5.9 cm. Next, the current value (I) when a DC voltage (V) of 100 V is applied between the comb-shaped electrodes is measured by a PA (picoampere) meter, and the resistance ρv is obtained by the following formula.

[0035]

[Equation 1]

Further, in the present invention, in order to obtain an environmentally stable surface layer, when a conductive material is contained in the surface protective layer, a siloxane compound or a fluorine atom-containing compound is dispersed at the time of dispersing the conductive particles. It is preferable to add the conductive particles or to mix the conductive particles that have been surface-treated in advance.

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

In the present invention, a lubricant may be contained in the surface layer for the purpose of improving releasability, water repellency and surface lubricity of the surface layer. Examples of the lubricant used in the present invention include tetrafluoroethylene resin, trifluorochloroethylene resin, hexafluoroethylene propylene resin, vinyl fluoride resin, vinylidene fluoride resin, difluorodichloroethylene resin, and their combination. It is preferable to appropriately select one kind or two or more kinds from the polymers, and 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. Further, by adding silica particles which are inorganic SiO ₂ particles, it becomes possible to increase the film strength.

As the binder resin used for the surface layer, a resin formed by three-dimensional cross-linking is used in order to have sufficient mechanical strength. Mechanical strength after curing, safety,
Thermosetting resins such as phenol resin, melamine resin, phosphazene resin, and acrylic resin are preferable because of the strength and resistance stability of the surface layer in the state of containing the conductive material and the charge transport material.

In particular, when the surface layer is formed using a thermosetting resin, the specific crystal form and structure described above as the charge generating material in the photosensitive layer such as phenol resin, melamine resin and thermosetting acrylic resin are used. By using the silicon phthalocyanine having the above, it becomes possible to satisfy both the sufficient mechanical strength of the surface layer formed by heat curing and the electrophotographic characteristics and environmental stability of the photosensitive layer.

Further, when the surface layer is formed using an ultraviolet curable resin, a resin containing two or more unsaturated bonds such as acryl group, methacryl group, vinyl group and allyl group in the molecule should be used. You can In particular, a compound containing an acryl group or a methacryl group can form a three-dimensional crosslinked film having sufficient strength by irradiation with ultraviolet rays.

Further, as the charge transport material contained in the surface layer of the present invention, a generally known charge transport material can be used. When a solvent having a high polarity such as alcohol or ketone is used for applying the surface layer, it is possible to use a charge transport material obtained by modifying the charge transport material with a hydroxyalkyl group, a hydroxyalkoxy group or an acrylic group. It becomes possible to uniformly dissolve the charge transport material in the surface layer.

FIG. 1 shows a schematic structure of an electrophotographic apparatus having a process cartridge having the electrophotographic photosensitive member of the present invention. In the figure, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member of the present invention, which is rotationally driven around a shaft 2 in a direction of an arrow at a predetermined peripheral speed. In the course of rotation, the photosensitive member 1 is uniformly charged with a predetermined positive or negative potential on its peripheral surface by the primary charging unit 3, and then image exposure from an exposing unit (not shown) such as slit exposure or laser beam scanning exposure. Receive 4.
In this way, electrostatic latent images are sequentially formed on the peripheral surface of the photoconductor 1. The formed electrostatic latent image is then toner-developed by the developing unit 5, and the developed toner image is synchronized with the rotation of the photoconductor 1 between the photoconductor 1 and the transfer unit 6 from a sheet feeding unit (not shown). The transfer material 6 is sequentially transferred to the transfer material 7 that is taken out and fed. The transfer material 7 that has undergone the image transfer is separated from the surface of the photoconductor and is introduced into the fixing means 8 to undergo image fixing, and is printed out of the apparatus as a copy. After the image transfer, the surface of the photoconductor 1 is cleaned by removing the transfer residual toner by the cleaning unit 9, and is further neutralized by the pre-exposure 10 from the pre-exposure unit (not shown). Used in forming. If the primary charging means 3 is a contact charging means using a charging roller or the like, pre-exposure is not always necessary. In the present invention, the electrophotographic photoreceptor 1 described above,
Of the components such as the primary charging unit 3, the developing unit 5, the cleaning unit 9 and the like, a plurality of components are integrally combined as a process cartridge, and the process cartridge is configured as an electrophotographic apparatus main body such as a copying machine or a laser beam printer. It may be configured to be removable. For example, at least one of the primary charging unit 3, the developing unit 5, and the cleaning unit 9 is integrally supported together with the photoconductor 1 to form a cartridge, and the cartridge can be detachably attached to the apparatus main body by using a guide unit such as a rail 12 of the apparatus main body. It can be the process cartridge 11. When the electrophotographic apparatus is a copying machine or a printer, the image exposure 4 reads reflected light or transmitted light from the manuscript, or reads the manuscript with a sensor, converts it into a signal, and scans a laser beam performed according to this signal.
It is the light emitted by the driving of the LED array and the driving of the liquid crystal shutter array.

The electrophotographic photosensitive member of the present invention can be widely used in electrophotographic copying machines, laser beam printers and the like, as well as electrophotographic application techniques such as CRT printers, LED printers, liquid crystal printers, fax machines and laser plate making.

[0045]

[Example] (Photosensitive layer example 1) φ30 mm x 260.5 mm
Of aluminum resin as a support, a 5% by mass solution of a polyamide resin (trade name: Amilan CM8000, manufactured by Toray Industries, Inc.) in methanol is applied by dipping,
An undercoat layer having a thickness of 0.5 μm was formed.

Next, Bragg angles 2θ (± 0.3 °) of CuKα characteristic X-ray diffraction of 7.1, 9.3, and 12.
0.4 g of dimerized dihydroxysilicon phthalocyanine having peaks at 8, 15.8, 17.2, 25.6 and 26.9 ° was mixed with 30 g of 4-methoxy-4-methyl-2-pentanone in a sand grind mill. Dispersed over time. Next, polyvinyl butyral (trade name: Denka Butyral # 6000C, manufactured by Denki Kagaku Kogyo Co., Ltd.)
0.1 g and phenoxy resin (trade name: UCAR, manufactured by Union Carbide Co., Ltd.) 0.1 g of 10% 4-methoxy-4-methyl-2-pentanone solution were mixed to prepare a coating solution. This coating solution was applied onto the above-mentioned undercoat layer by dip coating and dried at 90 ° C. for 10 minutes to form a charge generation layer so that the film thickness after drying was 0.4 μm.

Next, 10 parts by mass of a styryl compound having the following structural formula is added.

[0048]

[Chemical 3] And bisphenol Z type polycarbonate (trade name: Z
10 parts by mass of -200, manufactured by Mitsubishi Gas Chemical Co., Inc. was dissolved in 40 parts by mass of monochlorobenzene and 20 parts by mass of dichloromethane. This solution is applied onto the charge generation layer by a dipping method and dried with hot air at 100 ° C. for 60 minutes to give a film thickness of 20 μm.
m charge transport layer was formed.

(Photosensitive Layer Example 2) In Photosensitive Layer Example 1, the charge generation material was changed to a Bragg angle 2θ in CuKα characteristic X-ray diffraction.
(± 0.3 °) of 9.2 °, 14.1 °, 15.3 °,
A photosensitive layer was formed in the same manner except that dihydroxysilicon phthalocyanine having peaks at 19.7 ° and 27.1 ° was used instead.

(Photosensitive Layer Example 3) In Photosensitive Layer Example 1, the charge generation material was changed to the Bragg angle 2θ in CuKα characteristic X-ray diffraction.
(± 0.3 °) of 8.1 °, 12.2 °, 13.0 °,
17.0 °, 18.7 °, 23.3 °, 26.0 °, 2
A photosensitive layer was formed in the same manner except that dimethoxysilicon phthalocyanine having peaks at 7.8 and 30.4 ° was used instead.

(Photosensitive Layer Example 4) In Photosensitive Layer Example 1, the charge generation material was changed to the Bragg angle 2θ in CuKα characteristic X-ray diffraction.
(± 0.3 °) of 8.4 °, 10.9 °, 11.7 °,
A photosensitive layer was formed in the same manner except that diethoxysilicon phthalocyanine having peaks at 14.6 °, 16.7 °, 17.2 °, 24.6 ° and 26.8 ° was used instead.

(Photosensitive Layer Example 5) In Photosensitive Layer Example 1, the charge generation material was changed to the Bragg angle 2θ in CuKα characteristic X-ray diffraction.
(± 0.3 °) 10.7, 12.3, 15.5, 17.
A photosensitive layer was formed in the same manner except that dichlorosilicon phthalocyanine having peaks at 6, 19.9, 24.6, 26.8 and 27.6 ° was used instead.

(Photosensitive Layer Example 6) In the photosensitive layer example 1, the charge generation material was changed to a Bragg angle 2θ in CuKα characteristic X-ray diffraction.
(± 0.3 °) of 9.2 °, 14.1 °, 15.3 °,
0.2 g of dihydroxysilicon phthalocyanine having peaks at 19.7 ° and 27.1 ° and Bragg angle 2θ (± 0.3 °) of 8.1 ° and 12.2 in X-ray diffraction
°, 13.0 °, 17.0 °, 18.7 °, 23.3
A photosensitive layer was formed in the same manner except that a mixture of 0.2 g of dimethoxysilicon phthalocyanine having peaks at °, 26.0 °, 27.8 and 30.4 ° was used.

(Photosensitive Layer Example 7) A photosensitive layer was formed in the same manner as in Photosensitive Layer Example 1 except that the charge generation layer was formed as follows. That is, 1 part by mass of an azurenium salt compound represented by the following structural formula as a charge-generating material, butyral resin (trade name: ESLEK BM-2: manufactured by Sekisui Chemical Co., Ltd.)
1 part by mass and 30 parts by mass of isopropyl alcohol were dispersed for 4 hours with a ball mill disperser. This dispersion was applied onto the previously formed undercoat layer by dip coating to form a charge generation layer having a thickness of 0.3 μm.

[0055]

[Chemical 4]

(Photosensitive Layer Example 8) A photosensitive layer was formed in the same manner as in Photosensitive Layer Example 1 except that the charge generation layer was formed as follows. That is, 5 parts by mass of a trisazo compound represented by the following structural formula as a charge generation material, 2.5 parts by mass of butyral resin (trade name: Denka butyral resin # 3000-2; manufactured by Denki Kagaku Kogyo) and 9 parts of tetrahydrofuran
2.5 parts were dispersed in a ball mill for 12 hours, and then tetrahydrofuran was added so that the concentration of the dispersion liquid was 2% by weight, and dip coating was performed on the previously formed undercoat layer at 90 ° C. After drying for 10 minutes, the film thickness is 0.3μ
m charge-generating layer was formed.

[0057]

[Chemical 5]

(Example 1 of surface protective layer coating material) Conductive material surface-treated with a methylhydroxysiloxane compound (trade name: KF-99, manufactured by Shin-Etsu Chemical Co., Ltd.) (treatment amount: 8.2% by mass): antimony Fine particles of tin oxide (brand name:
T-1 (manufactured by Mitsubishi Materials Corp.) 50 parts by mass and ethanol 150 parts by mass are dispersed in a sand mill for 68 hours, and then a phenol resin (trade name: PL-4804, group) which is a resol type thermosetting resin. As a resin component, 31 parts by mass of Sakae Chemical Co., Ltd. was dissolved to obtain a surface protective layer coating material.

(Coating Example 2 for Surface Protective Layer) (3, 3, 3-
Conductive material surface-treated with trifluoropropyl) trimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) (treatment amount 7% by mass): antimony-containing tin oxide fine particles (trade name: T-
51 parts by mass of Mitsubishi Materials Co., Ltd. and 150 parts by mass of ethanol were dispersed in a sand mill for 66 hours,
Furthermore, polytetrafluoroethylene fine particles (average particle size of 0.
18 μm) 20 parts by mass was added and the mixture was dispersed for 20 minutes.
Then, a phenol resin (trade name: PL-4804, manufactured by Gunei Chemical Co., Ltd.) was dissolved as a resin component in an amount of 24 parts by mass to obtain a coating material for a surface protective layer.

(Example 3 of paint for surface protective layer) Phenolic resin (trade name: PR-53123, manufactured by Sumitomo Dures Co., Ltd.)
80 parts by mass and a charge transport material 3 represented by the following structural formula.
0 parts by weight, 10 parts by weight of inorganic silica particles are added to 20 parts of ethanol.
A coating material for the surface and surface protective layer was dissolved and dispersed in 0 part by mass.

[0061]

[Chemical 6]

(Coating Example 4 for Surface Protective Layer) (3, 3, 3-
Conductive material surface-treated with trifluoropropyl) trimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) (treatment amount 7% by mass): antimony-containing tin oxide fine particles (trade name: T-
50 parts by mass of Mitsubishi Materials Co., Ltd., melamine resin (trade name: Cymel 701, Mitsui Cytec Co., Ltd.)
39 parts by mass and 140 parts by mass of ethanol were dispersed in a sand mill for 66 hours to obtain a coating material for the surface protective layer.

(Example 5 of paint for surface protective layer) A conductive material surface-treated (treatment amount: 8.2% by mass) with a methylhydroxysiloxane compound (trade name: KF-99, manufactured by Shin-Etsu Chemical Co., Ltd.): Antimony-containing tin oxide fine particles (trade name:
50 parts by mass of T-1, manufactured by Mitsubishi Materials Corp., 20 parts by mass of styrene-methyl methacrylate-hydroxyethyl methacrylate copolymer and 150 parts by mass of methyl ethyl ketone were dispersed in a sand mill for 66 hours, and further hexa 10 parts by mass of isocyanurate of methylene diisocyanate was added to obtain a coating material for the surface protective layer.

(Example 6 of coating for surface protective layer) A conductive material surface-treated with a methylhydroxysiloxane compound (trade name: KF-99, manufactured by Shin-Etsu Chemical Co., Ltd.) (treatment amount: 8.2% by mass): Antimony-containing tin oxide fine particles (trade name:
50 parts by mass of T-1, manufactured by Mitsubishi Materials Corporation, acrylic resin (trade name: Calayad DPHA, Nippon Kayaku Co., Ltd.)
23 parts by mass and 150 parts by mass of ethanol were dispersed in a sand mill for 66 hours, and 2 parts by mass of 2-methylthioxanthone as a photopolymerization initiator was dissolved to obtain a coating material for a surface protective layer.

(Example 7 of surface protective layer coating material) In Example 1 of surface protective layer coating material, polyvinylphenol (trade name: PH), which is a thermoplastic resin, is used instead of the resol type phenol resin.
A coating material for the surface protective layer was formed in the same manner except that MC, Maruzen Petrochemical Co., Ltd. was used.

(Electrophotographic Photoreceptor Example 1) The photosensitive layer formed in Photosensitive Layer Example 1 was dip coated with the coating material for surface protective layer in Example 1 and then heat-cured at 150 ° C. for 1 hour. An electrophotographic photosensitive member was prepared by providing a surface protective layer having a film thickness of 3.0 μm.

(Electrophotographic Photoreceptor Examples 2 to 14) In the same manner as in the electrophotographic photoreceptor Example 1, as shown in Table 1, the photosensitive layer examples 1 to 4 and the surface protective layer coating examples 1 to 6 were used to form a tertiary layer. An electrophotographic photosensitive member having an original crosslinkable surface layer was prepared.

(Electrophotographic Photosensitive Member Example 15) Photosensitive Layer Example 1
After spray-coating the coating material for surface protective layer of the coating material of Example 5 on the photosensitive layer formed in 1), it is heat-cured at 150 ° C. for 1 hour to form a surface protective layer having a thickness of 3.0 μm. A photoconductor was created.

(Electrophotographic Photoreceptor Examples 16 and 17) On the photosensitive layers formed in the photosensitive layer examples 1 and 2, the coating material prepared in the coating example 6 for a surface protective layer was applied by dip coating to form a film.
The surface protection layer is cured by irradiating it with ultraviolet rays for 2 minutes at a light intensity of 1000 mW / cm ^{2 with} a high pressure mercury lamp, and then 1
The film was dried with hot air at 20 ° C. for 1 hour, and a surface protective layer having a film thickness of 3.0 μm was provided to prepare electrophotographic photoconductors, which were named electrophotographic photoconductor Examples 16 and 17, respectively.

(Electrophotographic Photosensitive Member Comparative Example 1) The photosensitive layer formed in Photosensitive Layer Example 7 was dip-coated with the coating material for surface protective layer of Example 1 and then heat-cured at 100 ° C. for 20 minutes. An electrophotographic photosensitive member was prepared by providing a surface protective layer having a film thickness of 3.0 μm.

(Electrophotographic Photosensitive Member Comparative Example 2) The photosensitive layer formed in Photosensitive Layer Example 7 was dip-coated with the coating material for surface protective layer of Example 1 and then heat-cured at 150 ° C. for 1 hour. An electrophotographic photosensitive member was prepared by providing a surface protective layer having a film thickness of 3.0 μm.

(Electrophotographic Photosensitive Member Comparative Example 3) The coating material for coating material for surface protective layer 6 was applied by dip coating on the photosensitive layer formed in Photosensitive Layer Example 8 to form a film, which was exposed to a high pressure mercury lamp at 20.
The surface protection layer is cured by irradiating it with ultraviolet light at a light intensity of 0 mW / cm ² for 15 seconds, and then dried with hot air at 100 ° C. for 1 hour to form a surface protection layer having a film thickness of 3.0 μm and electrophotographic sensitization. Created the body.

(Comparative Example 4 of electrophotographic photosensitive member) The coating material of coating material for surface protective layer 6 was applied by dip coating on the photosensitive layer formed in photosensitive layer example 8 to form a film.
The surface protection layer is cured by irradiating it with ultraviolet light at a light intensity of 0 mW / cm ² for 2 minutes, and then dried with hot air at 120 ° C. for 1 hour to form a surface protection layer with a film thickness of 3.0 μm. Created the body.

(Electrophotographic Photoreceptor Comparative Example 5) The photosensitive layer formed in Photosensitive Layer Example 1 was dip coated with the coating material for protective layer coating example 7 and then heat-cured at 150 ° C. for 1 hour.
An electrophotographic photosensitive member was prepared by providing a surface protective layer having a film thickness of 3.0 μm.

[0075]

[Table 1]

<Measurement of Volume Resistance of Surface Protective Layer> A comb-shaped electrode having a gap of 180 μm was formed on a polyethylene terephthalate sheet by gold vapor deposition, and the protective layer coating materials 1, 2, 4, 5 and 7 were formed thereon. Apply with a Mayer bar,
A heat treatment was applied to form a 3 μm film, and a volume resistance measurement sample was prepared. Similarly, a comb-shaped electrode was prepared by vapor deposition of gold, and the protective layer coating material 6 was applied on it by means of a Meyer bar, followed by ultraviolet irradiation by a high pressure mercury lamp and hot air drying to form a 3 μm film, and a volume resistance measurement sample was prepared. did.

The volume resistance measurement sample prepared as described above was measured at temperature / humidity of 23 ° C./50% RH and 30 ° C./80%.
After left in the two environments of RH for 1 day, 1 using a PA meter 4140B manufactured by Yokogawa Hewlett-Packard Co.
00 V was applied and measured.

[0078]

[Table 2]

<Evaluation of Electrophotographic Photosensitive Member> The electrophotographic photosensitive members prepared in the above-described Examples and Comparative Examples were mounted on a laser jet 4000 (roller contact charging, AC / DC applied) manufactured by Hewlett Packard Co., and the temperature was 23. ℃, humidity 5
The quality of the output image was confirmed in an environment of 0% RH, temperature of 30 ° C., and humidity of 80% RH.

Further, a paper passing durability test of 5000 sheets was conducted in an environment of a temperature of 23 ° C. and a humidity of 50% RH, and the output image after the durability test and the scraped amount of the electrophotographic photosensitive member were measured.

As a result of the durability test, Table 3 shows the quality of the output image and the abrasion amount (μm) on the surface after 5000 sheets.

As shown in Table 3, with the photoreceptors of Examples 1 to 17, good quality images can be obtained even under high temperature and high humidity, and the images after the durability test also maintain high quality. Moreover, the amount of abrasion of the photoconductor was extremely small.

On the other hand, in the case of the electrophotographic photosensitive members prepared in Comparative Examples 1 and 3, the surface layer was weakly hardened and the mechanical strength of the surface layer was weak. A large number of scratches were generated on the surface of the photoconductor, which appeared as black line defects in the image. Furthermore, since the curing reaction itself is incomplete,
When the humidity was high, the resistance of the surface layer was significantly reduced, and image deletion occurred under high temperature and high humidity. In Comparative Example 2 and Comparative Example 4, the hardness of the surface layer was sufficient, and no defects due to mechanical strength or resistance fluctuation of the surface layer were observed, but deterioration of the charge generation material during surface layer curing was observed. Remarkably, an image with sufficient density could not be obtained due to a decrease in sensitivity and an increase in residual potential.

Further, in Comparative Example 5, the sensitivity and the residual potential were not a problem, but the mechanical strength was remarkably weak because the surface layer was a thermoplastic resin, and the abrasion amount of the surface layer after the durability was large and the photoreceptor was large. Many scratches were generated on the surface, which appeared as black line defects in the image.

[0085]

[Table 3]

[0086]

As described above, according to the present invention,
In an electrophotographic photosensitive member having a surface layer formed by three-dimensionally cross-linking, by incorporating at least one phthalocyanine having a silicon atom at the center as a charge generating material, heat treatment or ultraviolet rays for curing the surface layer It is possible to provide an electrophotographic photosensitive member having sufficient strength without causing deterioration of the charge generating material due to irradiation and causing increase in residual potential and decrease in sensitivity, so that it has high durability, high stability, and good image quality. I was able to get

Further, the process cartridge having the electrophotographic photosensitive member and the electrophotographic apparatus also have the similar remarkable effect.

[Brief description of drawings]

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

[Explanation of symbols]

1 photoconductor 2 Photoconductor rotation axis 3 charging roller 4 image exposure 5 Developer 6 Transfer means 7 sheets 8 fixing roller 9 Cleaning blade 10 Pre-exposure 11 Cartridge frame 12 Cartridge guide

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koichi Nakata             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Daisuke Tanaka             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F-term (reference) 2H068 AA03 AA05 AA06 AA19 BA39                       BB06 BB29 BB31 BB33 BB35                       BB37 BB57 BB58 BB59 CA06                       CA37 CA60

Claims (12)

[Claims] 1. An electrophotographic photoreceptor having a photosensitive layer and a protective layer on a conductive support, the photosensitive layer containing at least one phthalocyanine having a silicon atom at the center as a charge generating material, and the protective layer. An electrophotographic photoreceptor, wherein the layer is a layer formed by three-dimensionally crosslinking. 2. The electrophotographic photosensitive member according to claim 1, wherein the protective layer contains at least one of conductive fine particles and a charge transport material. 3. The electrophotographic photosensitive member according to claim 1, wherein the protective layer is a layer provided by three-dimensionally crosslinking by heating and curing. 4. The electrophotographic photosensitive member according to claim 1, wherein the protective layer is a layer provided by three-dimensionally crosslinking by irradiation with ultraviolet rays. 5. The electrophotographic photosensitive member according to claim 1, wherein the protective layer contains at least one selected from the group consisting of silicone resin particles, silica particles, and fluorine atom-containing resin fine particles. 6. The electrophotographic photosensitive member according to claim 2, wherein the conductive fine particles are at least one of metal fine particles and metal oxide fine particles. 7. The electrophotographic photosensitive member according to claim 1, wherein the charge generating material is silicon phthalocyanine represented by the following general formula. [Chemical 1] (In the formula, R ₁ and R ₂ may be the same or different and each represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or a halogenated alkyl group. X ₁ , X ₂ , X ₃ and X ₄ are the same. Or may be different, and represents a halogen atom, an alkyl group having 1 to 8 carbon atoms or a halogenated alkyl group, a, b, c and d may be the same or different and represent an integer of 0 to 4, n represents an integer of 0 or more.) 8. A charge generation material having a Bragg angle 2θ (± 0.3 °) of 9.2 in CuKα characteristic X-ray diffraction,
The electrophotographic photosensitive member according to claim 1, further comprising a dihydroxysilicon phthalocyanine compound having peaks at 14.1, 15.3, 19.7 and 27.1 °. 9. A charge generating material having a Bragg angle 2θ (± 0.3 °) of 6.9 in CuKα characteristic X-ray diffraction,
8.0, 10.6, 16.0, 26.3 and 27.4 °
The electrophotographic photosensitive member according to any one of claims 1 to 7, further comprising a dimerized dihydroxysilicon phthalocyanine compound having a peak at. 10. The charge-generating material contains both a dihydroxysilicon phthalocyanine compound and a dialkoxysilicon phthalocyanine compound.
9. The electrophotographic photosensitive member according to any one of 9. 11. An electrophotographic apparatus main body, which integrally supports the electrophotographic photosensitive member according to claim 1 and at least one means selected from the group consisting of a charging means, a developing means and a cleaning means. Process cartridge characterized by being removable. 12. An electrophotographic apparatus comprising the electrophotographic photosensitive member according to claim 1, a charging unit, an image exposing unit, a developing unit, and a transferring unit.