JPS6333748A - Electrophotographic sensitive material - Google Patents

Abstract

PURPOSE:To obtain the titled material having a stabilized charge potential and residual potential by laminating an electric charge transfer layer, an electric charge generating layer and a surface protective layer having a low resistance in this order, and by dispersing one kind of the compd. selected from the group composed of a specific phthalocyanine derivative in the electric charge generating layer. CONSTITUTION:The titled material is formed by laminating the electric charge transfer layer 12, the electric charge generating layer 11 and the low resistance surface protective layer 10 on the conductive substrate 13 in this order, and the one kind of the compd. selected from the group comprising the phthalocyanine derivatives shown by formula (I), (II), (III) or (IV) is dispersed in the electric charge generating layer. The electric charge generating layer comprises the phthalocyanine derivative as an electric charge generating substance, and is formed by dispersing said derivative in a binding resin in an amount of 5-90wt%, preferably 20-50wt% on the weight basis of the total body. The particle size of the phthalocyanine derivative is 0.02-3mum, preferably, 0.05-1mum. The film thickness of each layers is 5-40mum in the electric charge transfer layer, <=5mum in the electric charge generating layer and 0.5-20mum in the surface protective layer having the low resistance, respectively. Thus, the titled body having the stabilized charge potential, even in case of a repeated use, is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an electrophotographic photoreceptor, and particularly relates to a charge generating material in a charge generation layer of an electrophotographic photoreceptor, and a low resistance surface protective layer. .

(Prior Art) Conventionally, there have been many configurations of laminated organic photoreceptors in which a charge generation layer is laminated as a lower layer of a charge transport layer. Since most of the charge transport layers commonly found at present have hole transport properties, it is necessary to use a photoreceptor having such a configuration with negative charging. For this reason, it has had various drawbacks that have an impact on the photoreceptor, such as generation of high concentration ozone due to negative charging and uneven charging of the corotron. In order to overcome this drawback, a charge generation layer is laminated as an upper layer of the charge transport layer and used for positive charging, and a low resistance surface protection layer is laminated as the top layer in order to improve mechanical strength and deterioration. A similar configuration was attempted. However, a photoreceptor with such a structure does not have sufficient surface chargeability and only a low contrast potential can be obtained, or even if chargeability is sufficient, light attenuation is insufficient and the residual potential is high, and the temperature and humidity are high. The charged potential and residual potential fluctuate due to changes in
It had various drawbacks, such as changes in charging potential and residual potential during repeated use, and a large decrease in sensitivity compared to before applying a surface protective layer.

(Problems to be Solved by the Invention) The purpose of the present invention is to provide an electrophotographic photoreceptor that does not have such drawbacks.
That is, it is an object of the present invention to provide an electrophotographic photoreceptor that prevents a decrease in charging potential, a high residual potential, the influence of temperature and humidity, and a decrease in sensitivity, and has stable charging potential and residual potential during repeated use.

(Means for Solving the Problems) The objects of the present invention can be achieved by using a specific phthalocyanine derivative as the charge generation material of the charge generation layer. Furthermore, the object of the present invention is to use a specific phthalocyanine derivative as a charge generation material of a charge generation layer, and to disperse fine particles of a specific conductive metal oxide in an insulating resin on the charge generation layer. This can be better achieved by providing a low resistance surface protective layer.

The present invention provides a charge transport layer, a charge generation layer, a charge transport layer and a charge generation layer on a conductive support.
Low-resistance surface protective layers are sequentially laminated, and one type selected from the group consisting of phthalocyanine derivatives represented by the following structural formulas (I), (n), (N), or (Company) is dispersed in the charge generation layer. This is an electrophotographic photoreceptor characterized by:

Structural formula (1) Structural formula (n) Structural formula (OI) Structural formula bond) In the present invention, it is not sufficient that the above-mentioned phthalocyanine derivative is contained in the entire generation layer of the ml, but it is preferable that the phthalocyanine derivative be dispersed. It is necessary and in this way the purpose can be achieved. Further, it is preferable that the phthalocyanine derivative is dispersed in the binder resin.

Supports with conductive surfaces used in the present invention include drums and notebooks made of metals such as aluminum, copper, iron, zinc, and nickel;
Vapor deposition of metals such as platinum, palladium, titanium, nickel-chromium, stainless steel, copper-indium, etc., vapor deposition of conductive metal compounds (e.g., N203, SnO□), lamination of metal foils, or casen black, conductive metal compounds (example,
In2O5,5b203- Sl2O3, SnO2, T
10x) Paper, plastic, glass, etc. in the form of Plam, sheet, or plate whose surface has been subjected to conductive treatment by dispersing powder, metal powder, etc. in a binder resin and applying it are used.

The charge transport layer used in the present invention includes a charge transport material, cytehagylene, N-ethylcarnozole, N-1sopropylcarnozole, 2,5-bis(p-diethylaminophenyl)-1,3,4- Oxadiazole, 1-phenyl-3-(P-diethylaminostyryl)-5-(P-diethylaminophenyl)pyrazoline, 1-(pyridyl-
(2))-3-(P-diethylaminostyryl)-5-
(P-diethylaminophenyl)pyrazoline, 1-[quinolyl-(2))-3-(P-diethylaminostyryl)-5-(P-diethylaminophenyl)pyrazoline,
Triphenylamine, N, N'-diphenyl N, N
'-bis(3-methylphenyl)-(1,1'-biphenyl:)-4,4'-diamine, 4-diethylaminostyryldehyr-1,1-diphenylhyrazone 4,
4/-hen I+) denupis (N, N'-diethyl-m-)luidine, poly N-vinylcarnozole,
Halogenated tree N-hinylcarnozole, ? Examples include ribinylpyrene, polyvinylanthracene, polyvinylacridine poly-9-vinylphenylanthracene, bi)/-formaldehydehyde Wt, and ethyl carnosol to formaldehy P resins. These charge transport materials can be used alone or in a mixture of two or more. 'i? However, the cargo transportation materials are not limited to those described herein. Binder resins used in the charge transport layer include acrylic resins, methacrylic resins,
General-purpose resins such as polystyrene, polyester, polyacrylate, polysal7one, and polycarzenate, and hole-transporting polymers such as polyN-pinylcarnozole can be used. Note that an adhesive layer may be provided between the conductive support and the charge transport layer.

The charge generation layer used in the present invention uses the above-mentioned phthalocyanine derivative as a charge generation material, and contains the phthalocyanine derivative in a binder resin in an amount of 90% by weight, preferably 20% to 50% by weight. It is distributed in proportion. The particle size of the phthalocyanine derivative is 0.02 μm to 3 μm.
1, preferably 0.05 μm to 1 μm. Binder resins for the charge generation layer include polyvinyl butyral, polyvinyl acetate, polyester, polycarbonate, phenoxy resin, acrylic resin, polyacrylamide, polyamide, polyvinylpyridine resin, casein, hol).
Various resins are used, such as vinyl alcohol and poly N-vinylcarnocesol.

The low resistance surface protective layer used in the present invention is one in which fine particles of a conductive metal oxide are dispersed in an insulating resin. Fine particles with an average particle diameter of 0.3 μm or less, preferably 0.1 μm or less that exhibit a blue-white color are suitable, such as antimony oxide, tin oxide, titanium oxide, indium oxide, tin oxide and antimony, or antimony oxide. These metal oxides may be used singly or as a mixture thereof, such as a solid solution of these metal oxides, or a mixture of these metal oxides in a single particle, or a coating thereof. Among them, tin oxide and antimony, a solid solution of antimony oxide, or tin oxide are preferably used because they can lower the electrical resistance and make the protective layer substantially transparent (fF opening). No. 57-30847, JP-A-57-1283
(See Publication No. 44).

The protective layer is desirably constructed so that its electrical resistance is 10 9 to 10 14 Ω. Electrical resistance is 10140・α
If it is more than 10 Ω·α, the residual potential will increase, resulting in a copy with a lot of fog, and if it is less than 10Ω·α, the image will be blurred and the resolution will be lowered. The protective layer must also be constructed so as not to substantially block the passage of light used for imagewise exposure. If the particle size of the conductive metal oxide used is too large, the protective layer becomes opaque, desensitization, and a decrease in image density occur. The particle size is determined by the wavelength of light used for image exposure (0,4
It is desirable to use particles having a particle diameter of 2 to 0.8 μm (n) or less, preferably one-half or less, that is, 0.3 μm or less, preferably 0.1 μm or less. Further, as the insulating resin, it is desirable to use an electrically insulating transparent resin whose electrical resistance does not easily change due to changes in humidity or temperature. As an insulating resin, polyamide P1? Examples include condensation resins such as urethane, polyester, epoxy resin, polyketone, and polycarbonate, and vinyl polymers such as polyvinyl ketone, polystyrene, and polyacrylamide. Among them, polyurethane is preferable in terms of film strength and chemical stability. used. The conductive metal oxide fine particles range from 20% by weight to 60% by weight based on the insulating resin.
It is desirable to disperse up to f1%. If it is less than 20% by weight, the electrical resistance will be more than 10140·α, which is 60% by weight or less.
If the weight exceeds -, the strength of the protective layer will drop significantly. Among these, it is preferable to perform the dispersion in a range of 30% by weight to 50% by weight.

Further, a charge injection blocking auxiliary layer may be further provided between the low resistance surface protective layer and the charge generation layer. Examples of the auxiliary layer forming material include coupling agents such as silane coupling agents and titanium coupling agents, organometallic compounds such as organic zirconium compounds and organic titanium compounds, and general-purpose resins such as polyester and polyvinyl butyral.

The appropriate thickness of each layer is 5 μm to 40 μm for the charge transport layer, preferably 8 μm to 30 μm, and 5 μm for the charge generation layer.
m or less, preferably 0.1 μm to 3 μm, and the low resistance surface protective layer has a thickness of 0.5 μm to 20 μm, preferably 1 μm to 10 μm.
μm is appropriate.

The specific structure of the present invention will be explained with reference to the drawings. FIG. 1 shows the basic structure of the present invention, in which a conductive support 13
A charge transport layer 12, a charge generation layer 11, and a low-resistivity surface protection layer 10 are sequentially laminated thereon to form an electrophotographic photoreceptor, and fine particles of a charge generation material 15 are dispersed in the charge generation layer. Furthermore, fine particles of conductive metal oxide 14 are dispersed in the surface protective layer. Figure 2 and the following diagrams show modified examples of the present invention, in which an adhesive layer 20 is provided between the conductive support 13 and the charge transport layer 12; 3 shows a structure in which a charge injection blocking auxiliary layer 30 is provided between a low resistance surface protection layer 10 and a charge generation layer 11, and FIG. An adhesive layer 20 is provided between the low resistance surface protection layer 10 and the charge generation layer 11, and a charge injection blocking auxiliary layer 30 is provided between the low resistance surface protection layer 10 and the charge generation layer 11.

(Function) The photoreceptor of the present invention has a high charging potential of 900 to 1180 square meters and can provide sufficient charging performance. A positively charged photoreceptor with a large photoreceptor is irradiated with 5 lux tungsten light for 3 seconds, and the surface potential is halved.
It is sufficient to irradiate light with a flux of seconds. The residual potential is also as low as 50-80μ. Even if the temperature and humidity are low and low humidity or high temperature and high humidity, the charging potential is high and the residual potential does not increase, so the charging potential and residual potential do not fluctuate due to changes in the environment. Furthermore, even if it is used repeatedly, the charged potential and residual potential change only slightly, so it is stable.

(Examples) Next, the present invention will be explained in more detail based on Examples, but the present invention is not limited to these Examples.

Example 1 An electrophotographic photoreceptor was prepared by sequentially laminating a charge transport layer, a charge generation layer, and a surface protection layer made of the following materials on an aluminum substrate.

Charge transport layer polycarbonate resin 60 parts by weight (20 parts by weight)
μ) (Kinjin Nigun Light) 4-diethylaminobenzaldehyr-1゜1-diphenylhydrazine 40 parts by weight Charge generation layer Phthalocyanine derivative 30 Heavy Stm (
0.5μ) (Structural formula (1)) At-ct polyvinyl butyral (Zukesui Kagaku: BM-1) 70 parts by weight Surface protective layer Tin oxide powder 40 parts by weight (2μ)
Polyurethane resin 60 parts by weight This photoreceptor was positively charged by discharging +6 kVo:lO using a commercially available electrostatic copying paper tester (Kawaguchi Electric: Electrostatic Penozo Analyzer 5P-428). Measure the surface potential VDDP after leaving it in the dark for 1 second, and immediately irradiate it with 5 lux tungsten light for 3 seconds to calculate the amount of light required to reduce VDDP by half -11E'A
I asked for Furthermore, after this, 200 lux light was irradiated for 0.5 seconds to further attenuate the surface potential, and the residual potential RP was determined. This measurement was performed at room temperature (25°C, 40% R).
).

This measurement is performed 1000 times in succession, and the difference between vDDP % RP between the 1st cycle and the 1000th cycle is calculated as Δ■D
Cycle stability was expressed as DP (C) and ΔRP (C).

Similar measurements were conducted under low temperature, low humidity (10°C, 2096RH) and high temperature, high humidity (30°C, 80% RH) environments, and the VDDP of the better one under either environment at the 1000th cycle was determined. The difference between VDDP and the worse VDDP under any environment at the 1000th cycle is defined as ΔVDDI, and 1
RP of the good person under any environment at the 000th cycle and RP of the affected person under any environment at the 1000th cycle
The environmental stability was expressed as ΔRP(E).

Each measured value in this example is shown below.

vDDP: 1130v EIA: 1.5 Lux・sec RP: 60V ΔDDP(C): l 00 V ΔRP(C)
: 30VΔDDP(a: 80VΔRP
(E:l:40V, that is, it can be said that it has sufficient chargeability, high sensitivity, and excellent cycle stability and environmental stability.

Comparative Example 1 A photoreceptor was exploded in the same manner as in Example 1, except that hlKβ type steel phthalocyanine was used in place of the chloraluminum phthalocyanine in the charge generation layer in Example 1, and the same measurements were performed, and the following values were obtained.

■DDP near 00v E17: 8.0 Lux・sec RP: 80V ΔvDDP(C): 250 v ΔRP(C
) = 30 vΔVDD, (E): 250 V
ΔRP (purity = 40■Low chargeability and cycle,
This indicates that there is a problem with the bi-stability of the environment.

Example 2 A photoreceptor was prepared and measured in the same manner as in Example 1, except that the surface protective layer in Example 1 was changed to tin oxide-antimony oxide solid solution/polyurethane resin = 40/60 (parts by weight), but the It exhibited stable characteristics similar to those of the photoreceptor of Example 1.

■DDP: 1060v E: 1.5 Lux・sec RP: 50V ΔVDDP(C): 90V ΔRP(C)
: 20 VΔVDDP(E:l 2 9 0
VΔRP(E): 30V
Example 3 A P-ram type photoreceptor was manufactured under the same conditions as Example 2, and this photoreceptor was installed in our modified machine to form a copy image.The photoreceptor was high in contrast, faithful to the original, and clear. A visible image was obtained.

Further, the copying was repeated 1000 times, and until the end, the same image as the first copy was obtained.

Example 4 The following material system was spray-coated on a PET substrate on which aluminum was vapor-deposited, and then dried to form a charge transport layer with a thickness of 20 μm.

Polycarbonate resin 10 parts (Imato:
/ξNlite L1250) N,N'-diphenyl-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine 8 parts by weight Methylene chloride 40 parts by weight Trichloroethane 40 parts by weight The following material system uniformly dispersed with Nipaint conditioner was spray coated and dried to form a charge generation layer with a thickness of 1 μm.

Phthalocyanine derivative 2 parts by weight (Structural formula (ID) V=0 Polyvinyl butyral resin 3 parts by weight (Kusui Kagaku: BM-1) Methylene chloride 40 parts by weight Trichloroethane 55 parts by weight Further, on top of this, homogeneous dispersion was performed using a Zeel mill. After spray coating the following material system, it was dried to form a surface protective layer with a thickness of 2 μm.

Tin oxide powder 4 parts by weight Polyurethane resin sTiTi base Methylene chloride 35 parts by weight Trichloroethane
56 parts by weight The photoreceptor thus obtained was measured using an electrostatic copying paper tester (Kawaguchi Electric: Electrostatic Paper Analyzer EPA-8100) under normal temperature and normal humidity (25°C, 404RH). The following characteristic values were obtained.

VDDP (surface potential 1 second after corona charging of +25 μA): 950V Ev2 (1 exposure required to reduce VDDP by half) = 1.
0 lux・sec RP (residual potential): 80V
This cycle of charging and exposure was repeated 1000 times to obtain the following characteristic values.

ΔvDDP(C) (1000 cycles teno vDDP)
Change): 40V ΔRP(C) (Change in RP up to 1000 cycles):
30V Furthermore, TvDDP1RP was measured under low temperature and low humidity (10° C., 20 RH) and high temperature and high humidity (30° C., 804 RH), and the following characteristic values were obtained.

ΔvDDP(E) (Change in VDDP due to environmental conditions)
: 60v ΔRP (1 (change in RP due to environmental conditions): 40V Therefore, it can be said that this photoreceptor has sufficient chargeability, high sensitivity, excellent cycle stability, and environmental safety.

When the image quality characteristics of the similarly obtained photoreceptor were evaluated using a Fuji Xerox XP-9 laser beam printer, it was confirmed that sufficient image quality was maintained up to 50 KCV or higher.

Example 5 A photoreceptor having a 2μ thick surface protective layer was produced in the same manner as in Example 4, except that the surface protective layer in Example 4 was changed to the following material system.

Oxide, e/antimony oxide solid solution 3 parts by weight Polyurethane resin 5 parts by weight Methylene chloride
35 parts by weight trichloroethane
57 parts by weight The same measurements as in Example 4 were carried out, and sufficient chargeability, high sensitivity, and excellent stability were shown.

VDD, : 900 V EV2 : 1.2 Lux・sec RP Near 0 V ΔVnop(C) : 90 V ΔRP(C)
: 30 V"■nDp (1:100V ΔRP
(1:40V Example 6 A photoreceptor was prepared by sequentially laminating a charge transport layer, a charge generation layer, and a surface protection layer made of the following materials on an aluminum substrate.

Charge transport layer Polycarbonate resin 60 parts by weight (20 parts by weight)
μ) (odd person ξn light) 4--) ethylaminobenzalde and r-1.

1-diphenylhydrazine 40 parts by weight Charge generation layer Phthalocyanine derivative 40 parts by weight (1,
0μ) (Structural formula (In)) (Mg) 60 parts by weight of polyvinyl butyral (Kusui Kagaku: BM-1) Surface protective layer Tin oxide powder 40 parts by weight (2μ
) - Urethane resin 60 overlapping parts This photoreceptor was tested using a commercially available electrostatic copying paper testing device (Kawaguchi Electric: Electrostatic Paper Analyzer 5P-428) at +6 kV.

Measure the surface potential VDDP after performing a negative discharge to positively charge it and leaving it in a dark place for 1 second.Immediately after that, 5 lux tungsten light is irradiated for 3 seconds, and the light required to reduce vDDP by half is f'14. E% was calculated. Furthermore, after this, 2
The surface potential was further attenuated by irradiating light of 0.00 lux for 0.5 seconds, and the residual potential RP was determined. This measurement was performed at normal temperature and normal humidity (25° C., 40% RH).

This measurement is performed 1000 times in succession, and the difference in VDD, RPO between the 1st cycle and the 1000th cycle is ΔVDDP.
(C), cycle stability was expressed as ΔRP(C).

Similar measurements were conducted under low temperature, low humidity (10°C, 20% RH) and high temperature, high humidity (30°C, 80% RH) environments. Let ΔVDDP(1 be the difference between the vDDP of
The better RP under any environment at the 000th cycle and the worse RP under any environment at the 1000th cycle
The environmental stability was expressed as ΔRP (E:l).

VDD: 1150 V E%: 1. Full 7x・sec RP: 60VΔDDP (
C) = 120■ ΔRP(c): 30VΔDDP(E
): 80V ΔRP(E): 30V, that is, it can be said that it has sufficient chargeability, high sensitivity, and excellent cycle stability and environmental stability.

Example 7 A photoreceptor was prepared and measured in the same manner as in Example 6, except that the surface protective layer in Example 6 was changed to tin oxide-antimony oxide solid solution/polyurethane resin = 40/60<X slip part). It exhibited stable characteristics similar to those of the photoreceptor of Example 6.

■oDP: 1O80v E112: 1.6 Lux・sec RP: 50V ΔVDDp (Q: 100V ΔRP (C)
: 20VΔVDDp(a: 90V
ΔRP (El: 30 V Example 8 A P-ram microphotoreceptor was manufactured under the same conditions as Example 7, and this photoreceptor was installed in our modified machine to form a copy image. A clear and faithful visible image was obtained.

The copying process was repeated 1,000 times, but an image equivalent to the first copy was obtained up to the size.

Example 9 A photoreceptor was prepared by sequentially laminating a charge transport layer, a charge generation layer, and a surface protection layer made of the following materials on an aluminum substrate.

Charge transport layer Polycarbonate resin 60 parts by weight (20 parts by weight)
μ) (Imajin Nipanrite) 4-diethylaminobenzaldehyde-1゜1-diphenylhydrazine 40 parts by weight Charge generation layer Phthalocyanine derivative 30 parts by weight (0,
5, a) (Structural formula (fv)) In -CL polyvinyl butyral (Tanesui Kagaku: BM-1) 70 parts by weight Surface protective layer Tin oxide powder 40 parts by weight (2μ)
Polyurethane resin 60 parts by weight This photoconductor was positively charged by +6kV corona discharge using a commercially available electrostatic copying paper tester (Kawaguchi Electric: Electrostatic Benon-Analyzer 5P-428), and then left in the dark for 1 second. Measure the surface potential VDDP after leaving it at
The light iEμ required to reduce DDP by half was determined. Furthermore, after this, 200 lux light was irradiated for 0.5 seconds to further attenuate the surface potential, and the residual potential RP was determined. This measurement was performed at room temperature and humidity (25°C, 404RH).

This measurement is performed 1000 times in succession, and the difference between VDDP1 RP at the 1st cycle and the 1000th cycle is calculated as ΔvDD.
Cycle stability was expressed as P(C:) and ΔRP(C).

In addition, similar measurements were carried out under a low temperature, low humidity environment (10°C, 20SRH) and a high temperature, high humidity environment (30°C, 80SRH), and the VDDP and 1000 of the better one under either environment at the 100th cycle were The difference between the VDDP of either cycle in the worst environment is ΔvDDP (satoshi, and 10
RP and 1 of the better one under any environment in the 00th cycle
The environmental stability was expressed as ΔRP (F3), which was the difference from the RP under the worse environment at the 000th cycle.

Each measured value in this example is shown below.

■DDP: 1180■ To E: 1. Flux seconds RP: 50V ΔVDDP(C): 110V ΔRP(C)
: 20 VΔVDDP (1: 70 V
ΔRP(E): 30 V, that is, it can be said to have sufficient chargeability, high sensitivity, and excellent cycle stability and environmental stability. Example 10 The surface retention layer in Example 9 was made of tin oxide. - Antimony oxide solid solution/polyurethane resin = 40/60 (parts by weight) K
A photoreceptor was produced and measured in the same manner as in Example 9 except for the changes, and it showed stable characteristics similar to those of the photoreceptor of Example 9.

■DDP: 1090v E dedication: 1. Flux seconds RP: 50V ΔvDDp(C): 90V ΔRP(C)
: 20VΔVonp(e: 80V
ΔRP (1: 20 V Example 11 A P ram type photoreceptor was manufactured under the same conditions as Example 1O, and this photoreceptor was installed in our modified machine to form a copy image. A clear and faithful visible image was obtained.

Although the copying process was repeated 1000 times, the same image as the first copy was obtained until the end.

[Brief explanation of the drawing]

1 to 4 are sectional views of specific examples of the electrophotographic photoreceptor of the present invention. 10...Low resistance surface protective layer, 11...Charge generation layer,
12... Charge transport layer, 13... Conductive support, 14
... Conductive metal oxide, 15... Charge generating material, 2
0...adhesive layer, 30...charge injection blocking auxiliary layer. 'A

Claims (4)

[Claims] (1) A charge transport layer, a charge generation layer, and a low resistance surface protection layer are sequentially laminated on a conductive support, and the charge generation layer has the following structural formula (I), (II), (III), or (IV 1. A photoreceptor for electrophotography, characterized in that one kind selected from the group consisting of phthalocyanine derivatives represented by the following is dispersed. Structural formula (I) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ Structural formula (II) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ Structural formula (III) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ Structural formula (IV) ▲Contains mathematical formulas, chemical formulas, tables, etc.▼ (2) The electrophotographic photoreceptor according to claim (1), wherein the phthalocyanine derivative is dispersed in a binder resin. (3) The electrophotographic photoreceptor according to claim (2), wherein the phthalocyanine derivative is dispersed in the binder resin in a proportion of 5% to 90% by weight of the total weight. (4) The low-resistance surface protective layer is composed of a layer in which fine particles of a conductive metal oxide are dispersed in an insulating resin, and the conductive metal oxide has an electrical resistance of 10^9 Ω·cm or less and an average particle size of 0.
The electrophotographic photoreceptor according to claim (1), which has particles of 3 μm or less.