JP2003215824A - Electrophotographic image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To develop an electrophotographic image forming device which realizes both of a small-sized device and fast printing speed. <P>SOLUTION: The electrophotographic image forming device houses an electrophotographic photoreceptor having a base coating layer containing a resin soluble with water, alcohol or a water/alcohol mixture solvent and a photosensitive layer containing a N,N'-bisenamine compound expressed by general formula (1) on a conductive supporting body. In this device, the period from initiating exposure to completion of development is ≤90 msec. <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 image forming apparatus, and more specifically, it comprises an undercoat layer containing a specific resin and a charge transport layer containing a specific N, N'-bisenamine compound. The present invention relates to an electrophotographic image forming apparatus that realizes high speed and downsizing of the apparatus.

[0002]

2. Description of the Related Art Inorganic photoconductive materials such as selenium, cadmium sulfide and zinc oxide have been used as materials for forming a photosensitive layer of an electrophotographic photoreceptor. These inorganic photoconductive materials have many advantages, such as being able to be charged to an appropriate potential in the dark, and having little respect for electricity in the dark.
On the other hand, it has various advantages such as being able to quickly dissipate electric charges by light irradiation.
For example, selenium-based photoconductors have difficult manufacturing conditions,
The manufacturing cost is high and it is vulnerable to heat and mechanical shock, so handling must be done carefully. Cadmium sulfide-based photoconductors and zinc oxide photoconductors do not provide stable sensitivity in humid environments, and the dye added as a sensitizer causes charge deterioration due to corona charging and photobleaching due to exposure, resulting in long-term It has a drawback that it cannot provide stable characteristics over the entire range. Further, since selenium and cadmium sulfide are toxic to humans and the environment, it has been necessary to completely collect and dispose of these inorganic photoconductors after use.

On the other hand, various organic photoconductive polymers such as polyvinylcarbazole have been proposed.
These polymers are superior to the above-mentioned inorganic photoconductive materials in terms of film-forming property and lightness, but in view of sufficient sensitivity, durability and stability due to environmental changes, the inorganic photoconductive materials are excellent. Is inferior to. In recent years, various researches and developments have been carried out in order to solve the drawbacks and problems of these photoconductors, so that the charge generation function and the charge transport function of the photoconductive function can be divided into separate substances to form a laminated type or a dispersed type. The function-separated type photoconductor is proposed. Such a function-separated type photoconductor has a wide selection range of each substance, charging characteristics,
It is possible to provide a high-performance photoconductor by combining the best substances in electrophotographic properties such as sensitivity, residual potential, repetitive property and printing durability. Further, since it can be produced by coating, it has an advantage that it is possible to provide a photoreceptor having extremely high productivity and an inexpensive price, and further, it is possible to freely control the photosensitive wavelength region by appropriately selecting the charge generating material. At present, most copying machines and printers have such a function-separated type photoreceptor (organic photoreceptor:
OPC) has come into use.

However, in recent years, copying machines, printers,
For electrophotographic devices such as facsimiles and electrophotographic plate making machines, downsizing of devices, higher printing speed, and longer life are required, and downsizing, high response, and long life of electrophotographic photoconductors are also required. There is an increasing demand for conversion. Fuji Xerox Technical Report No. 11 (199) is one means to achieve downsizing of electrophotographic devices and higher printing speed.
6) "New OPC technology for laser exposure" IR-ST ""
In order to reduce the size of the drum and the system speed by improving the responsiveness by using a charge transport material having high mobility in the electrophotographic photoreceptor, the size of the electrophotographic apparatus and the printing speed can be improved. The technology to achieve high speed is introduced. Japanese Unexamined Patent Publication No. 8-62862 discloses an electrophotographic image forming apparatus using a photoconductor having a specific mobility in a charge transport layer, aiming at downsizing of an electrophotographic apparatus and high printing speed. ing.

On the other hand, a photoreceptor containing a water-soluble polyvinyl acetal as an undercoat layer of the electrophotographic photoreceptor for the purpose of improving charging property and preventing image defects (Japanese Patent Laid-Open No. 63-1782).
49), a photoreceptor containing a water / alcohol mixed solvent-soluble polyvinyl acetal (JP-A-6-59489).
Japanese Patent Laid-Open No. 48-47344) has been proposed. The photoconductor containing these resins in the undercoat layer has a large production technology that the undercoat layer does not melt when the photosensitive layer is coated and formed when a nonaqueous solvent or a non-alcohol solvent is used in the photosensitive layer. However, even if a high-mobility charge transport material is used, it has the drawback of causing a reduction in residual potential and responsiveness especially at low temperature and low humidity because it has the property of increasing volume resistance at low humidity. There is. Further, JP-A-6-110229 discloses an electrophotosensitive material having a photosensitive layer containing an N, N'bisenamine compound represented by the general formula (1) of the present invention for the purpose of high sensitivity and high durability. ing.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to develop an electrophotographic image forming apparatus which uses an electrophotographic photosensitive member having a high response to achieve both miniaturization of the apparatus and high printing speed. To do.

[0007]

As a result of intensive studies to achieve the above object, the present inventors have found that an undercoat layer containing a specific resin and a specific N, N'-bisenamine compound By incorporating an electrophotographic photosensitive member having a photosensitive layer contained therein, an electrophotographic image forming apparatus has been successfully developed which realizes downsizing of the apparatus and high printing speed, and has completed the present invention.

That is, the present invention comprises an undercoat layer containing at least one resin which is soluble in water, alcohol or a water / alcohol mixed solvent system on a conductive support, and a general formula (1) And an electrophotographic photoreceptor having a photosensitive layer containing an N, N'-bisenamine compound represented by the formula (1), an electrophotographic image forming apparatus having a time from the start of exposure to the end of development of 90 msec or less. It is provided.

[Chemical 3] (In the formula, A is an arylene group which may have a substituent, a divalent heterocyclic residue which may have a substituent, or an alkylene group which may have a substituent, and Ar ₁ represents The aryl group which may have a substituent and the heterocyclic group which may have a substituent are shown, Ar ₂ represents the aryl group which may have a substituent and the heterocyclic group which may have a substituent, and Z is Ar ₂ together with Ar _2. The atomic groups necessary to form a ring are shown.)

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The conductive support of the photoconductor incorporated in the electrophotographic image forming apparatus of the present invention is not particularly limited, and known materials can be used. For example, aluminum, aluminum alloy, copper,
Metal drum or sheet shape made of zinc, nickel, stainless steel, titanium, etc., polymer material such as polyethylene terephthalate, phenol resin, nylon, polystyrene, glass or hard paper, metal foil lamination, metal vapor deposition treatment, Alternatively, a drum, sheet, seamless belt shape or the like in which titanium oxide, tin oxide, indium oxide, carbon black or the like is coated with a conductive substance together with a suitable binder to be subjected to a conductive treatment is exemplified.

An undercoat layer containing, as a main component, water, alcohol or a water / alcohol mixed solvent-soluble resin in order to improve adhesiveness and charge blocking property between the conductive support and the photosensitive layer. Is provided. As the water-soluble resin, polyvinyl alcohol, polyvinyl acetal,
A particularly preferred water-soluble resin such as casein and sodium polyacrylate is polyvinyl acetal. The alcohol-soluble nylon resin is copolymer nylon, methoxymethylated nylon, etc., and the water / alcohol mixed solvent-soluble resin is preferably polyvinyl acetal. In order to prevent moire and reduce residual potential, a fine powder pigment of a metal oxide such as titanium oxide, silica, alumina, zirconium oxide, tin oxide or indium oxide can be added to the undercoat layer. Particularly preferred is titanium oxide.

The thickness of the undercoat layer is preferably 0.1 μm.
m or more and 20 μm or less, more preferably 1 μm or more and 5 μm
The range is as follows. When the thickness of the undercoat layer is less than 0.1 μm, the undercoat layer does not substantially function as the undercoat layer, and the defects of the conductive support are covered so that uniform surface properties cannot be obtained. It becomes impossible to prevent the carrier injection, and the chargeability is deteriorated. On the other hand, 20 μm
If it is thicker than the above range, it is not preferable because the formation of the photoreceptor becomes difficult and the mechanical strength of the coating film is lowered when the undercoat layer is applied by dip coating. The dispersion method of the coating liquid for the undercoat layer includes a ball mill, a sand mill, an attritor, a vibration mill, a colloid mill, an ultrasonic disperser, etc., and its application means is a dipping method, a spray method, a bead method, a nozzle method. General methods such as, can be applied.

The structure of the photosensitive layer formed on the undercoat layer may be either a function-dispersed type composed of two layers of a charge generation layer and a charge transport layer or a single layer type formed of a single layer. It is better, however, that the function-dispersed type can select the most suitable material for each layer and is excellent in stability during repeated use. In the case of the function separation type, the charge generation layer is formed on the undercoat layer. Examples of the charge generating substance contained in the charge generating layer include bisazo compounds such as chlorodian blue, polycyclic quinone compounds such as dibromoanthansulone, perylene compounds, quinacridone compounds, phthalocyanine compounds, and azurenium salt compounds. It is known and it is possible to use two or more of these in combination.

As a method for forming the charge generating layer, there are a method of vacuum-evaporating a charge generating substance and a method of dispersing and coating in a binder resin solution to form a film, but the latter method is generally preferable. . In the case of coating, the same method as that for the undercoat layer is used for the method of mixing and dispersing the charge generating substance in the binder resin solution and the coating method. Examples of the binder resin include melamine resins, epoxy resins, silicone resins, polyurethane resins, acrylic resins, polycarbonate resins, polyarylate resins, phenoxy resins, butyral resins, and copolymer resins containing two or more repeating units, such as chloride. Insulating resins such as vinyl-vinyl acetate copolymer resin and acrylonitrile-styrene copolymer resin can be mentioned, but not limited to these, and all commonly used resins are used alone or in combination of two or more. Can be used. Further, as a solvent for dissolving these resins, halogenated ash of methene chloride, acetone, methyl ethyl ketone, ketones such as cyclohexanone, ethyl acetate, esters such as butyl acetate tetrahydrofuran, ethers such as dioxane, Aromatic hydrocarbons such as benzene, toluene, xylene, and aprotic polar solvents such as N, N′-dimethylacetamide can be used. The thickness of the charge generation layer is preferably 0.05 μm or more and 5.0 μm or less, more preferably 0.1 μm or more and 1.0 μm or less.

Next, as a method for forming the charge transporting layer provided on the charge generating layer, a charge transporting coating solution prepared by dissolving a charge transporting substance in a binder resin solution is applied by a usual method. The method of forming a film is common. As the charge transporting material contained in the charge transporting layer, the N, N′-bisenamine compound represented by the general formula (1) is used. Furthermore, it may be used in combination with one or more known charge transport substances such as hydrazone compounds, triphenylamine compounds, triphenylmethane compounds, stilbene compounds, oxadiazole compounds, and other enamine compounds. It is possible. As the binder resin, the same resin as the above-mentioned resin for the charge generation layer is used. As the method for forming the charge transport layer, the same method as for the undercoat layer is used, and the film thickness thereof is preferably 5 μm or more and 50 μm or less,
More preferably, it is in the range of 10 μm or more and 40 μm or less. The representative compounds of the N, N′-bisenamine compound represented by the general formula (1) are shown below. These compounds are synthesized, for example, by the synthetic method described in Japanese Patent No. 2812620.

[0015]

[Chemical 4]

[Chemical 5]

[Chemical 6]

[Chemical 7]

[Chemical 8]

When the photosensitive layer has a single-layer structure, the thickness of the photosensitive layer is preferably 25 μm or more and 50 μm or less, and more preferably 25 μm or more and 40 μm or less. Further, if necessary, a protective layer may be provided to protect the surface of the photosensitive layer. As the material, thermoplastic resin or light or thermosetting resin can be used. The protective layer may contain an ultraviolet ray inhibitor, an antioxidant, an inorganic material such as a metal oxide, an organic metal compound, an electron accepting substance and the like. Further, if necessary, a plasticizer such as a dibasic acid ester, a fatty acid ester, a phosphoric acid ester, a phthalic acid ester, or chlorinated balafine is mixed with the photosensitive layer and the surface keeping layer to improve the processability and flexibility. Grant,
Mechanical properties may be improved, and a leveling agent such as a silicone resin may be used.

(Examples) Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1: Diameter 30 mm, length 340 mm
Aluminum drum and 0.2 mm thick aluminum plate (JIS
1080) was coated with the following undercoat layer coating solution by dip coating to a thickness of 1 μm. After application, heat drying was not performed. [Undercoat layer coating liquid] Titanium oxide TTO-55A (manufactured by Ishihara Sangyo) 5 parts by weight Polyamide resin CM8000 (manufactured by Toray) 5 parts by weight Methanol 130 parts by weight n-butanol 60 parts by weight Disperse the above components in a paint shaker for 10 hours. Then, a coating liquid for the undercoat layer was prepared.

Next, the following charge generation layer coating solution was applied onto the undercoat layer by dip coating, dried at 120 ° C. for 10 minutes, and the thickness was reduced to 0.
A 2 μm charge generation layer was formed. [Charge generation layer coating liquid] Oxotitanium phthalocyanine 2 parts by weight Polyvinyl butyral resin BLl (Sekisui Chemical Co., Ltd.) 2 parts by weight Cyclohexanone 100 parts by weight The above components are dispersed for 2 hours in a paint shaker to prepare a charge generation layer coating liquid. Was prepared. Next, the following charge emitting / transporting coating solution was applied onto the charge generating layer by dip coating and dried at 110 ° C. for 60 minutes to form a 25 μm charge transporting layer to obtain an electrophotographic photoreceptor. [Charge Transport Layer Coating Liquid] Exemplified Compound (11) 6 parts by weight Polycarbonate resin Z300 (manufactured by Mitsubishi Gas Chemical Co., Ltd.) 9 parts by weight Silicone oil KF50 (manufactured by Shin-Etsu Chemical) 0.002 parts by weight Tetrahydrofuran 60 parts by weight Mixture having the above composition Was stirred and dissolved to prepare a charge transport layer coating solution.

Example 2: Exemplified compound (11) of Example 1
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the compound (48) was replaced with.

Example 3: Exemplified compound (11) of Example 1
Was replaced by 5 parts by weight, and the polycarbonate resin was replaced by 10 parts by weight to prepare an electrophotographic photoreceptor in the same manner as in Example 1.

Example 4: Exemplified compound (11) of Example 1
Was replaced by 7 parts by weight and the polycarbonate resin was replaced by 8 parts by weight to prepare an electrophotographic photoreceptor in the same manner as in Example 1.

Example 5: An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the coating liquid for undercoat layer of Example 1 was prepared as follows. [Undercoat layer coating liquid] Titanium oxide TO-55A (manufactured by Ishihara Sangyo) 3 parts by weight Water-soluble polyvinyl acetal resin KW-1 (manufactured by Sekisui Chemical Co., Ltd.) 3 parts by weight (weight of solid content) 30 parts by weight of water 70 parts by weight of methanol Parts The above components were dispersed with a paint shaker for 10 hours to prepare an undercoat layer coating solution. Although the water-soluble polyvinyl acetal resin KW-1 is actually an aqueous solution, only the weight of the solid content is shown in the description.

Example 6 An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the coating solution for undercoat layer of Example 1 was prepared as follows. [Undercoat layer coating liquid] Titanium oxide TTO-55A (manufactured by Ishihara Sangyo) 3 parts by weight Water / alcohol-soluble polyvinyl acetal resin KX-1 (manufactured by Sekisui Chemical Co., Ltd.) 3 parts by weight (solid content) Water 60 parts by weight Isopropyl Alcohol 40 parts by weight The above components were dispersed in a paint shaker for 10 hours to prepare an undercoat layer coating liquid. Although the water / alcohol-soluble polyvinyl acetal resin KX-1 is actually a water / alcohol solution, only the weight of the solid content is shown in the description.

Comparative Example 1: Electrophotographic sensitization was carried out in the same manner as in Example 1 except that the charge generation layer and the charge transport layer were formed by coating on the drum and the aluminum plate without coating the undercoat layer of Example 1. The body was made.

Comparative Example 2: An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that the coating liquid for undercoat layer of Example 1 was prepared and coated as follows. [Undercoat layer coating liquid] Titanium oxide TTO-55A (manufactured by Ishihara Sangyo) 98 parts by weight Oil-free alkyd resin Nekkolite M6401 (manufactured by Dainippon Ink, 50% solid content) 30 parts by weight Melamine resin Super Beckamine L121 (Dainippon Japan) Ink, solid content 60%) 16 parts by weight Methyl ethyl ketone 100 parts by weight The above components were dispersed in a paint shaker for 10 hours to prepare an undercoat layer coating solution. After that, after dip-coating on the drum to a thickness of 1 μm, heat treatment was carried out at 150 ° C. for 30 minutes to cure the resin because a thermosetting resin was used.

Comparative Example 3: Exemplified compound (11) of Example 1
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that was replaced by the following compound.

[Chemical 9]

Comparative Example 4: Exemplified compound (11) of Example 5
An electrophotographic photosensitive member was produced in the same manner as in Example 5 except that the compound of Comparative Example 3 was replaced with.

Comparative Example 5: Exemplified compound (11) of Example 6
An electrophotographic photosensitive member was produced in the same manner as in Example 6 except that the compound in Comparative Example 3 was replaced.

Comparative Example 6: Exemplified compound (11) of Comparative Example 1
An electrophotographic photosensitive member was produced in the same manner as in Comparative Example 1 except that the compound of Example 3 was replaced with.

Comparative Example 7: Exemplified compound (11) of Comparative Example 2
An electrophotographic photosensitive member was produced in the same manner as in Comparative Example 2 except that the compound of Example 3 was replaced with.

Comparative Example 8: Exemplified compound (11) of Example 1
An electrophotographic photosensitive member was produced in the same manner as in Example 1 except that was replaced by the following compound.

[Chemical 10]

Comparative Example 9: Exemplified compound (11) of Example 5
An electrophotographic photosensitive member was produced in the same manner as in Example 5 except that the compound of Comparative Example 8 was used instead of.

Comparative Example 10: Exemplified compound of Example 6 (1
An electrophotographic photosensitive member was produced in the same manner as in Example 6 except that 1) was replaced with the compound of Comparative Example 8.

Comparative Example 11: Exemplified compound (1
An electrophotographic photosensitive member was produced in the same manner as in Comparative Example 1 except that 1) was replaced with the compound of Comparative Example 8.

Comparative Example 12: Exemplified compound of Example 2 (1
An electrophotographic photosensitive member was produced in the same manner as in Example 2 except that 1) was replaced with the compound of Comparative Example 8. The following evaluations were performed on the electrophotographic photoreceptors produced in the above Examples and Comparative Examples.

[Evaluation 1] The electrophotographic photosensitive member produced on an aluminum plate was charged to -600 V by an electrostatic paper test apparatus EPA-8200 (manufactured by Kawaguchi Denki) while rotating the sample at 1100 rotations, and then 1 μW / cm. 780 at a strength of ²
It was evaluated by a so-called dynamic method, in which sensitivity was measured by irradiating monochromatic light of nm. The sensitivity results are shown below.

Exposure dose (μJ / cm ² ) required to attenuate from −600 V to −300 V Example 1 0.13 Example 2 0.14 Example 3 0.13 Example 4 0.13 Example 5 0.12 Example 6 0.14 Comparative Example 1 0.12 Comparative Example 2 0.13 Comparative Example 3 0.16 Comparative Example 4 0.15 Comparative Example 5 0.16 Comparative Example 6 0.15 Comparative Example 7 0. 17 Comparative Example 8 0.12 Comparative Example 9 0.13 Comparative Example 10 0.13 Comparative Example 11 0.12 Comparative Example 12 0.14 From the above results, Comparative Examples 3 to 7 were used in comparison with the Examples. The sensitivity is poor when the compound is used, but Comparative Example 8
It can be seen that those using the compounds of ~ 12 have the same sensitivity as that of the example.

[Evaluation 2] The electrophotographic photosensitive drum was mounted on a machine in which the laser beam printer DM4501 manufactured by Sharp was remodeled for regular development and the light amount of the image exposure light source and the linear velocity of the photoconductor were variable. When the linear velocity of the photoconductor was changed and the background stain was generated, the exposure light amount was increased, and the image quality of the image copy in which the degree of the change did not change was evaluated. The results of performing this in an environment of 25 ° C., 55% and 5 ° C., 20% are shown below.

[0040]                 The state of image background stains from the start of exposure                 Until the end of development                 Time (msec) 25 ℃, 55% 5 ℃, 20%     Example 1 50 Good Good                     90 Good Good                   130 Good Good     Example 2 50 Good Good                     90 Good Good                   130 Good Good     Example 4 50 Good Good                     90 Good Good                   130 Good Good     Example 4 50 Good Good                     90 Good Good                   130 Good Good     Example 5 50 Good Good                     90 Good Good                   130 Good Good     Example 6 50 Good Good                     90 Good Good                   130 Good Good     Comparative Example 1 50 Good Good                     90 Good Good                   130 Good Good     Comparative Example 2 50 Good Good                     90 Good Good                   130 Good Good     Comparative Example 3 50 Soil generation Soil generation                     90 Soil generation Soil generation                   130 Good Soil generation     Comparative Example 4 50 Soil generation Soil generation                     90 Soil generation Soil generation                   130 Good Soil generation     Comparative Example 5 50 Soil generation Soil generation                     90 Soil generation Soil generation                   130 Good Soil generation     Comparative example 6 50 Soil generation Soil generation                     90 Soil generation Soil generation                   130 Good Soil generation     Comparative Example 7 50 Soil generation Soil generation                     90 Soil generation Soil generation                   130 Good Soil generation     Comparative Example 8 50 Good Stain generation                     90 Good Soil generation                   130 Good Good     Comparative Example 9 50 Good Soil generation                     90 Good Soil generation                   130 Good Good     Comparative Example 10 50 Good Soil generation                     90 Good Soil generation                   130 Good Good     Comparative Example 11 50 Good Good                     90 Good Good                   130 Good Good     Comparative Example 12 50 Good Good                     90 Good Good                   130 Good Good

As described above, in the samples in which the undercoat layers of Comparative Examples 1, 6, and 11 were not provided, the background stain did not occur, but the dot-like image defects due to the charge injection from the drum occurred.
The thermosetting undercoating layers of Comparative Examples 2, 7, and 12 have good screen characteristics, but a thermosetting reaction step is required after the undercoating layer is applied. The water-soluble, water / alcohol mixed solvent-soluble Examples and Comparative Examples are inferior in productivity as compared with the case where the curing (drying) step is not required. In addition, comparing with the result of Evaluation 1, it can be seen that not all those having good sensitivity have good responsiveness.

[Evaluation 3] The electrophotographic photosensitive drums produced in Examples 1, 3 and 4 were subjected to a printing durability test of 50,000 sheets with a modified laser beam printer DM4501 manufactured by Sharp. As a result, in Examples 1 and 3, the good image quality was maintained even after 50,000 sheets, whereas in Example 4, the background stain caused by the film abrasion occurred after 50,000 sheets. It was also found that the one having a ratio of the N, N′-bisenamine compound to the binder resin of 2/3 or less was particularly excellent in printing durability.

[0043]

As described above in detail, in the electrophotographic image forming apparatus of the present invention, the conductive indicator contains a resin soluble in water, alcohol or a water / alcohol mixed solvent. A pulling layer and N represented by the general formula (1),
An electrophotographic photoreceptor having a photosensitive layer containing an N-bisenamine compound was provided, and the time from the start of exposure to the end of development was 90 msec or less, so that it was possible to increase the printing speed even with a small diameter drum.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takashi Obata             22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka             Inside the company (72) Inventor Akihiro Kondo             22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka             Inside the company F term (reference) 2H068 AA20 AA33 AA43 AA44 BA03                       BA13 BB28 BB50 EA14

Claims (8)

[Claims] 1. An undercoat layer containing at least one resin soluble in water, alcohol or a mixed solvent system of water and alcohol on a conductive support, and N represented by the following general formula (1). An electrophotographic image forming apparatus having a time from the start of exposure to the end of development of 90 msec or less, the electrophotographic photosensitive member having a photosensitive layer containing a N'-bisenamine compound. [Chemical 1] (In the formula, A is an arylene group which may have a substituent, a divalent heterocyclic residue which may have a substituent, or an alkylene group which may have a substituent, and Ar ₁ represents The aryl group which may have a substituent and the heterocyclic group which may have a substituent are shown, Ar ₂ represents the aryl group which may have a substituent and the heterocyclic group which may have a substituent, and Z is Ar ₂ together with Ar _2. The atomic groups necessary to form a ring are shown.) 2. N, N ′ represented by the general formula (1)
The electrophotographic image forming apparatus according to claim 1, wherein the bis enamine compound is a compound represented by the following general formula (2). [Chemical 2] (In the formula, R ₁ is an alkyl group having 1 to 5 carbon atoms which may include a substituent, an alkoxy group having 1 to 3 carbon atoms, and 1 to 5 carbon atoms.
Of indicates thioalkoxy group, R ₂ represents an optionally contain a substituent alkyl group of 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a thioalkoxy group having 1 to 5 carbon atoms or a hydrogen atom, m represents an integer of 1, 2, 3, 4, 5. However, when m is 2 or more, R ₂ may be the same or different. ) 3. The electrophotographic image forming apparatus according to claim 1, wherein the resin is water-soluble polyvinyl acetal. 4. The electrophotographic image forming apparatus according to claim 1, wherein the resin is a water / alcohol mixed solvent-soluble polyvinyl acetal. 5. The electrophotographic image forming apparatus according to claim 1, wherein the resin is an alcohol-soluble nylon resin. 6. The electrophotographic image forming apparatus according to claim 1, wherein the undercoat layer contains titanium oxide. 7. The photosensitive layer is a function-separated type having a charge generation layer and a charge transport layer, and the charge transport layer comprises an N, N′-bisenamine compound represented by the general formula (1) and a binder resin. 7. The electrophotographic image forming apparatus according to claim 1, wherein the ratio of the N, N′-bisenamine compound and the binder resin is 2/3 or less. 8. A photoconductor used in the electrophotographic image forming apparatus according to claim 1.