JPS59191043A - Laminate type electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To increase the sensitivity of a laminate type sensitive body and to reduce the optical memory effect by restricting the degree of hole transfer of the sensitive body. CONSTITUTION:When a charge generating layer and a charge transferring layer are successively laminated on an electrically conductive support to manufacture a negatively chargeable sensitive body, an org. photoconductive compound having >=10<-5>cm<2>/V.sec degree of drift transfer of holes (positive holes) in a two- layered system is used. The compound has the value in an electric field having 2.5X10<5>V/cm strength. The photoconductive compound generates larger carriers in the charge generating layer and implants them more efficiently into the charge transferring layer in accordance with an increase in the degree of transfer. It is preferable that an org. accepting substance having >=10<-6>cm/V.sec degree of drift transfer of electrons is used in the underlayer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic photoreceptor, in which a charge generation layer and a charge transport layer are provided on a conductive support, and the present invention relates to an electrophotographic photoreceptor in which a charge generation layer and a charge transport layer are provided on a conductive support. is 10 c
The present invention relates to a laminated electrophotographic photoreceptor characterized by using an organic photoconductive compound having a value of rn2/v of 000 or more.

BACKGROUND ART Conventionally, electrophotographic photoreceptors of the type in which a charge generation layer and a charge transport layer are laminated on a conductive support are known.

However, with this type of laminated photoreceptor, sufficient sensitivity has not yet been obtained, and when the photoreceptor is repeatedly charged and flashed immediately after being exposed to strong light, it is difficult to obtain sufficient sensitivity. There were 9 drawbacks to the so-called optical memory effect, in which the dark area level varied greatly. Furthermore, in conventional laminated photoconductors, it has been found that various attempts to improve the sensitivity are always accompanied by an increase in the above-mentioned original memory effect. So far it has not been obtained.

OBJECTS OF THE INVENTION It is an object of the present invention to eliminate the above-mentioned drawbacks and to provide a laminated electrophotographic photoreceptor that is highly sensitive and at the same time has an extremely small optical memory effect.

Structure and effect of the invention The laminated photoreceptor X photoreceptor of the present invention has a conductive support,
In a negatively charged electrophotographic photoreceptor provided with a charge generation layer and a charge replenishment layer, the degree of drift of holes in the two-layer system is 10% r'/v, sec or more. It is desirable to use a shelled phototetraelectric compound having a value of .

As a result of the fact that the sensitivity of the 1ζ type photoreceptor, which is prepared by separating the photosensitive materials J and B into the charge generating layer and the charge-generating layer, is not improved, the charge-generating material and the "if material" are used. Inside, there are many gear traps generated by irradiation, and the poles and electrons generated by light irradiation cannot move efficiently. It is conceivable that this is not occurring efficiently.At the same time, it is thought that the inefficiency of carrier movement and carrier injection as described above causes a large optical memory effect.

Sensitivity is one of the most important characteristics of a photoreceptor, but in the case of a functionally separated photoreceptor, the sensitivity is generally: (1) 1↓ (light intensity extinction coefficient) when light reaches the charge generation layer (2) Efficiency of gear generation in the charge generation layer (carrier generation magneton efficiency) (3) Injection rate of A~Ya from the tongai layer to the ichi 6rl, yomi 1,)shi (ionization 7j''Y (tensial, oxidation level, etc.) (4) Qualitative solidification as a comprehensive rice coagulation process, such as the efficiency of casting by carrying 1 in the load rake 7-1. Expressed - stiff.

In order to improve the sensitivity, the light absorption i7T+ of 4.I should be applied to the photoreceptor.
It is best to check the number, fi 4 seedlings, keyyariya injection efficiency, tonmuhang kanshu, kuju, drift, mobility, etc. Now, assuming that the intensity of the irradiated light is constant, the extinction coefficient and
4. It seems unlikely that we will be able to significantly increase the erosion of child efficiency. (:Rako'1.ru.Furthermore, from the dragon fK Dingo life layer to the Iii, I(L琶ζ1♂tongue layer) °de Yaryao people〃.

The rate is considered to be an important factor that affects sensitivity, but the measurement method is based on the method of measurement. Oxidation as a direct method; It is just an established tL.

Furthermore, charge-generating materials that are mostly pigment-based
Even the method for measuring g+:tj has not been established. From the above, it can be said that there are no clear guidelines from the Agency regarding carrier injection and increasing the lJJ rate.

Therefore, let us next consider drift mobility in the charge transport layer. In general, drift mobility (μd) is determined by a complex physical property that determines the hyperactivity velocity and conductivity of optical carriers in a photoconductive material. According to this standard method Vζ, it is possible to directly observe the movement of carriers generated on the surface of the sample by pulsed light irradiation to the ff1K field as an induced current, and carrier movement in the photoconductive material can be directly observed. It is a well-known fact that important insights regarding the behavior and trapping of carriers can be obtained.

Therefore, in order to design a highly sensitive photosensitive material, it is considered that increasing the hyperactivity of holes in the charge transport layer is an important factor.

In general, the hole mobility of various organic photoconductive compounds is
The 61i1 constant σ for the charge transporting material alone, or for threads containing molecular fractions of it in a polymer, is 61i1 constant σ, and although the value varies somewhat depending on the measurer, it is 10 to 10 (1
)2/v, sec over a wide range.

By the way, mobility is a physical property value that can be measured for a single material, but in a functionally separated photoreceptor, the charge generation layer (C!GL) is usually a charge transport layer (CT).
Since the number of layers is much smaller than that of 0GL-C, and there is almost no difference in dielectric constant between OGL and OTL, the present inventors developed 0GL-C.
TL 2 j The drift mobility of the eel system was conveniently defined and M1j constant was attempted. If defined like this,
In effect, we are measuring the mobility of CTL, and I:! Since TL normally uses materials that do not absorb visible light, by using a CGL-CTL multilayer system,
Mobility measurement can be easily performed using visible light. Furthermore, such a measurement method corresponds to the actual system of corona charging and visible light in the electrophotographic process.

This is a method that allows you to directly observe the carrier generation and movement behavior of electrophotography.

Therefore, the present inventors developed the CGL-OTL2I as described above.
- As a result of measuring the drift mobility of the system for many combinations of charge generation materials and charge transport materials, we found that the drift mobility of holes in the 0GL-OTL two-layer system is a stacked type with a value of 1 o '' cm27 V, eec or more. We discovered that the photoreceptor has extremely high sensitivity and at the same time the optical memory effect mentioned above is extremely small. However, the drift mobility of organic photoconductive compounds other than organic crystals that are generally used in electrophotographic photoreceptors depends on the electric field strength. Therefore, the above values are for an electric field strength of 2.5 x 105 V/l:m.

Yet another discovery is that materials with high mobility in the OGL-OTL two-layer system generate many carriers in the CGL and simultaneously (inject them efficiently into the COTL).

The above discoveries indicate that by using a material that can efficiently generate carriers in the CGL, efficiently inject carriers into the OTL, and move quickly in the CTL, it is possible to realize a laminated photoreceptor with high sensitivity and a small optical memory effect. It shows.

As described above, it has been found that by measuring the drift mobility of holes in the CGL-CTL two-layer system, useful information can be obtained for the selection of material for transporting cargo and material for transporting cargo.

As described above, the experimental results show that a laminated photoreceptor using an acceptor organic material with an electron drift mobility of 10-6 i/v, sec or more in the subtraction 1~1 has a very high sensitivity and photoreceptor. The memory effect was also found to be small. Therefore, next, we conducted a theoretical study on the meaning of the above-mentioned values of 10%2/v and eea.

1.C! hen and J, Mort,, T, App.
In the literature, Phys., 43.1164 (1971), a theoretical analysis of the E-V (light intensity - surface potential) characteristics of a single node photoreceptor was carried out, and the Jd particle efficiency of carrier generation and carrier generation were investigated. Assuming an appropriate electric field dependence on mobility,
The correspondence between these first shifts and the E~■ characteristic curves is discussed. Therefore, with reference to this literature, we attempted to fix the sensitivity.

The sensitivity value is E% (lux), which represents the amount of light transmitted (illuminance 5 lux) required to attenuate the electric cry (■1) into a mass when the photosensitive chamber is corona-charged and dark decayed for 1 second. , sθ
Using the storm called C), I performed j1 ascending and attended the following ceremony.

In the above formula, the meaning of each letter is as follows.

○: Capacity of photoreceptor per unit center of face Vη: Voltage at which η-1 is obtained in the empirical formula η(''V)=(V/Vη) expressing the electric field dependence of carrier generation quantum efficiency, Pe is a parameter.

θ; Charge F = original strength, unit is (PhotoQns/m2eac); Empirical formula expressing electric field dependence of carrier mobility μ-μ0
(v/■1) Pm value, V = V1 no R no μ value IP value upper Pm meter L: Photoreceptor film thickness formula (1) For higher sensitivity, reduce the value of El, 2 For this purpose, (1) increase in image light intensity CF), (2) increase in carrier generation quantum efficiency (decrease in η)
(3) Increase in mobility (μ0) (4) It is clear that it is necessary to take into account factors such as decrease in Pm. Here (1
) In the equation, mobility means the value when the values and electric field dependence of both electrons and holes are exactly the same.If there is a difference in the mobility characteristics of electrons and holes, the quantitative expression is It has not been implemented in the literature due to mathematical difficulties. Therefore, using a functionally separated photoconductor that performs negative charging as an example,
An attempt was made to calculate the theoretical sensitivity value by substituting only the hole mobility value of the charge transport layer into equation (1). The following physical property values were used at that time.

0=255pF/m2. Vη=10'V, F=10
"photons/>2secθ=160X10-19
Coulomb, μo=6XiO-6. :1n2/v, e
ecV1=600V, Pe=1. Pm=0.9. L=1
6×10 −4 crn However, the value of μ0 here is selected from typical literature values for organic charge transport materials.

As a result of calculation, the theoretical value is 8%-〇, i 51ux, s
A value of θC was obtained. This value shows that the sensitivity is much higher than that of inorganic material photoreceptors (3N, 2-11ux, 5ea) such as aas-p sθ, which is said to be more sensitive than organic material photoreceptors. There is.

Possible reasons why the theoretical value of sensitivity becomes such a small value as described above are as follows. In deriving equation (1), we used the assumption that the gear generated by light irradiation is smoothly injected from the charge generation layer to the charge transport layer and travels through the charge transport layer without being trapped. There is. However, in reality, carrier movement is hindered due to charge generation holes and carrier traps existing in the charge transport layer, and carrier injection from the charge generation layer to the charge transport layer is not performed smoothly. Due to the time loss, the measured value of IH,2 becomes larger than the theoretical value, resulting in low sensitivity.

Furthermore, although it is a future task to make the above-mentioned time loss effect constant, it is clear that this effect also causes the original memory.

Therefore, reducing the effect of this time loss as much as possible depends on selecting a material with high mobility and few carrier traps. From the above, it is presumed that in order to realize a photoreceptor with high sensitivity and at the same time a small optical memory effect, there is a lower limit of the mobility.

The above discussion is about the movement of holes, but it is necessary for high sensitivity and low optical memory that even when electrons are injected, they are smoothly injected from the charge generation layer to the attraction layer, and that they move quickly in the undercoat layer. , it is thought that a lower limit also exists for the value of electron mobility of the undercoat layer. In fact, as shown in Example 7, which will be described later, it has been found that when the electron mobility of the undercoat layer is less than a certain value, the sensitivity deteriorates and the edge and original memory effects become large. This lower limit value is 1 Ll-
'cy'/v, sec was clarified by comparing and examining the measurement results of the electron 1 hyperactivity of the undercoat layer and the measurement results of electrophotographic special four.

In addition, the standards for high-sensitivity, low-light memory in the present invention include a sensitivity of El, 4, 5 to 6 lux,
sec Below, for optical memory, please refer to the method of the example described later: Difference between charge level before and after strong Δ light irradiation ■ 1 1 ΔV
11 was set to 30V or less. The only photosensitive material that satisfies these two conditions at the same time, other than Hontakuma, is the eutectic agglomeration type photoreceptor disclosed in Japanese Patent Publication No. 1983-40531. All other photoreceptors other than Nanki's had a very large optical memory effect, even if they had high sensitivity.

The charge generation layer used in the present invention includes biryllium, thiopyrylium-based Somekun, phthalonanine-based Gan-i →, Andor/Thron Gan-bu-to, dibenzpyrenequinone pigment, and Biran IC: 1.
Separate deposited layers or resin-dispersed layers can be used.

The charge generation layer can be formed by dispersing the charge generation substance described above in a suitable binder and coating it on the substrate. 1: It can be obtained by forming a evaporated N film using a vacuum evaporation apparatus. The binder used when forming the charge generating layer by coating can be selected from a wide range of insulating resins, and poly-N-vinyl carba sheets can be used as the binder.
l.

One can choose from organic photoconductive polymers such as polyvinyla/thracene and polyhinylpyrene. Preferably, polyvinyl butyral, polyarylate (such as a 1 m 3+ -combination of bisphenol A and 7-talic acid), polycarbonate, polyester, noenoxy resin, polyvinyl acetate, acrylic resin, polyacrylamide resin, polyamide, polyvinylpyridine, cellulose resin, urethane resin,
Examples include insulating resins such as epoxy resin, casein, polyvinyl alcohol, and polyvinylpyrrolidone. The resin contained in the charge generation layer is suitably at most 80:1 iq6, preferably at most 40% by weight. Coating 1
Examples of organic fa agents used in this case include alcohols such as methanol, ethanol, and imbronoξol, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, amides such as N,N-dimethylformamide, N,h↓-dimethylacetamide, Sulfoxides such as dimethyl sulfoxide, ethers such as tetrahydrofuran, dioxane, and ethylene glycol monomethyl ether, esters such as methyl acetate and ethyl acetate, and aliphatic halogens such as chloroform, methylene chloride, dichloroethylene, carbon tetrachloride, and trichlorethylene. Polymerized hydrocarbons or aromatics such as benzene, toluene, xylene, refloin, monochlorobenzene, dichlorobenzene, etc. can be used.

In another embodiment of the invention, a eutectic complex of a biryllium dye and an electrically insulating polymer having an alkylidene diarylref moiety as disclosed in U.S. Pat. This eutectic complex is, for example, 4-[4-bis-(2-10-loethyl)aminophenyl]=2.6-dinenylthiavirilliumnoξ-
Chlorate and poly(4,4'-isopropyritene diphenylene carbonate) were treated in a halogenated hydrocarbon solvent (e.g., dichloromethane, chloroform, carbon tetramide, 1
．． 1-dichloroethane, 1,2-dichloroethane,
1. 1,2-trichloroethane, chlorobenzene, promobe/cene, 1,2-dichlorobenzene) and coated on a support, the layer is brought into contact with vapors of the solvent of the dye mentioned above to form particulates. Obtained as a eutectic complex.

The electrophotographic photoreceptor in this example includes styrene-butadiene copolymer, silicone resin, vinyl resin, vinyl chloride/-acryloni) I), n, near hol)
Polymer, styrene-acrylonitrile copolymer, vinyl acetate-)-vinyl chloride copolymer, polyvinyl butyral, polymethyl methacrylate, poly-N-butyl methacrylate, polyesters, cellulose esters, etc. can be contained as a binder.

In another specific example, a layer containing a dye in a dye-dye interaction state and an electrically insulating polymer pinter described in Japanese Patent Publication No. 54.83837 can be used as the charge generation layer. This material is, for example, 4-((2
, 6-diphenyl-4H-thioviran-4-ylidene)
-Methylcou 2,6-cyphenylthiovirylium perchlorate and poly[414'-(hexahydro-4,7-
After coating a layer containing [meta)inda/-5-ylidene)diphenylene terephthalate] on a support, the layer is brought into contact with vapor of a solvent for the dye to transfer the dye to a state of dye-dye interaction. The resulting material can also be used as a charge generation layer.

In yet another embodiment of the present invention, the disazo pigments described above or US Pat.
Byrylium dyes, thiapyrylium dyes, selenapyrylium dyes, benzobyrylium dyes, benzothiapyryllium dyes disclosed in Publications No. 38 and 3586500, etc.
Photoconductive pigments and dyes such as naphthopyryllium dyes and nandothiapyrylium dyes can also be used as sensitizers.

Coating methods include dip coating, spray coating, spinner coating, bead coating,
This can be carried out using a coating method such as a Mayer bar coating method, a blade coating method, a roller coating method, or a curtain coating method.

The charge generation layer incorporates as many of the organic light guides as possible in order to obtain sufficient light absorbance, and in order to shorten the range of the generated charge carriers, a thin film layer, e.g.
It is preferable to form a thin film layer having a thickness of less than a micron, preferably aoi micron to 1 micron. This means that most of the incident light is absorbed by the charge generation layer, generating many charge carriers, and that the generated charge carriers are transported by recombination or trapping without being deactivated. This is due to the fact that the astringency injected into the layer is
There is.

A light layer consisting of a laminated layer of such a direct shipping layer and a ball transport layer is provided on a foil body having a conductive layer.

The base material for forming the conductive layer 1 is one that has 22 metal properties, such as aluminum, aluminum alloy, copper, zinc, stainless steel, vanadium, molybdenum, chromium, titanium, nickel, indium, gold, platinum, etc. In addition, plastics (e.g., polyethylene, (polyrib L7 birene, polyvinyl chloride, polyethylene terephthalate, acrylic resin, polyethylene 7t), conductive particles (e.g. carphone blank, silver particles 4, etc.) on top of the plastic with a suitable pinter. A coated substrate, a substrate in which plastic or paper is impregnated with conductive particles, a plastic having a conductive polymer, etc. can be used.

It is also possible to provide a dowel 7/island with a burr function and a bonding machine 1 on the conductive layer and the sensitive droplet. Dobiki Noah contains cargoine, hollyvinyl alcohol, nitrocellulose, ethylene-7cryl a copolymer, polyamide (I[J-6, nylon 66, nylon 610,
cobase nylon, alkoxymethylated nylon, etc.),
:r,' Refletan, Ceratin, Aluminum oxide 7t
Doyotsu-C can be formed.

The film thickness of the undercoat and eyebrows is 0.1 micron to 5 micron, preferably (t: 0.5 micron - filtration and Y-inner armpit).

7~ is pyrene, N-ethylcarbazole, N-inopropylcarbazole, N-methyl-N-phenylhydrazino~6-methylidene-9-ethyl Carbazole, N,N-ginylhydra, 6-methylidene-9-ethylcarbazole, N,N-nnoenylhyI',l",; ,/
-3-methylif-/-1U-enalnoenothiazine, N
, N-knobylhydracino-6-methylidene-10-
Ethylphenoxazine, p-ethylaminohene/saldehyde N, N-diphenylhydrazone, p-diethylaminohenzaldehyde N-α-naphthyl-N-phenylhydrazone, p-e lolidinylbenzaldehyde N, N-n Phenylhydrazo/, 1.3.3-)
Tsumethylindolenine-ω-aldehyde-N, N-diphenylhydrazone, p-diethylbenzaldehyde-
Hydrazones such as ro-methylbenzthi7zolinone-2-hydrazone, 2,5-bis(p-diethylaminophenyl)-1,3,4-oxadiazole, 1-phenyl-
6-(p-diethylaminostyryl)-5-(p-diethylaminophenyl)pyrazoline, 1-[Kinotsuru (2
> )-ro-(p-diethylaminostyryl)-5-(
p-diethylaminophenyl)pyrazoline, 1-[pyridyl(2)]-6=(p-diethylaminostyryl)-
5-(p-diethylaminophenyl)pyrazoline, 1-
(6-Medoxybilidyl(21)=3-(p-diethylaminostyryl)-5-(p-diethylaminophenyl)pyrazoline, 1-[pyridyl(3J)-3-
(p-zoegelaminostyryl)-5-(p-diethylaminophenyl)pyrazoline, 1-[Levidil (2)
J -3-(p-diethylaminostyryl>-5-<p
-diethylaminophenyl)pyrazoline, 1-[pyridyl(2)) -3-(p-diethylaminostyryl)
-4-Methyl-5-(p-diethylaminophenyl)pyrazoline, 1-[pyridyl(2)) -3-(α-methyl-p-diethylaminostyryl)-5-(p-diethylaminophenyl)pyrazoline 1.1- phenyl-3
-(p-diethylaminostyryl)-4-methyl-5-
(p-:, ;ethylaminophenyl)bi7sol J/, 1
-Phenyl-3-(α-benzyl-p-diethylaminostyryl)-5-(p-diethylaminophenyl)pyrazoline, spiropyrazoline, and other pyrazolines f+'2-
(p-diethylaminostyryl)-6-noethylaminobenzoxazole, 2-(p-diethylaminophenyl)-4-(p-methylaminophenyl)-5-(2
-chloronoenyl)oxole-specific oxbuzole thread compounds, thiazole compounds such as 2-(p-ethylaminostyryl)-6-dinithylaminobenzothyanol, bis(4-diethylamino-2-methylphenyl) −
Triarylmethane compounds of Phenylmethane Temple, 1,
1-bis(4-N,N-ethylamino=2-methylphenyl)butane, 1,1,2.2-tetrakis(4-
N,N-dimethylamino-2-methylphenyl)ethane polyarylalkanes, triphenylamine, poly-N-vinylcarpanol, polyvinylpyrene, polyvinylanthrace/, polyvinylpyrene, poly-9-
Materials selected from charge transport materials such as vinylphenylanthracene, helene-formaldehyde resin, ethylcarbazole formaldehyde resin, etc. can be used.

Further, these charge transport substances can be used alone or in combination of two or more.

When the charge transport material does not have film-forming properties, a film can be formed by selecting an appropriate binder. Resin 1i that can be used as a binder, for example acrylic 41
Insulating resins such as polyester, polycarbonate, polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-phtadiene, copolymer, polyvinyl butyral, polyvinyl formal, polysulfone, polyacrylamide, polyamide, chlorinated rubber, or (-1: poly -N-Vinylcarbazole, polyvinylanthracene, polyvinylpyrene organic photopolymer polymers can be used.

The charge transport layer cannot be made thicker than is safe because there is a limit to how much charge can be transferred along the axis. Generally, the range is between 5 microns and 30 microns, but a preferred range is between 8 microns and 20 microns. To form the charge transport layer by coating, any suitable coating method described above can be used.

The electrophotographic photoreceptor provided by the present invention can be used not only for electrophotographic copying machines, but also for laser printers and CRTs.
It can also be widely used in electrophotographic applications such as printers.

Further, the organic photoconductor of the present invention can also be used in solar cells and optical sensors in addition to the above-mentioned electrophotographic photoreceptor.

Solar cells can be prepared by sandwiching the aforementioned organic photoconductors with, for example, indium oxide and aluminum.

According to the present invention, it is possible to provide an electrophotographic photoreceptor that has high sensitivity and at the same time has a small optical memory effect.

Hereinafter, the present invention will be explained according to examples.

Example 1 was dissolved in methylene chloride 30CeK bath. This coating solution was applied onto an aluminum sheet using a Mayer bar so that the dry film thickness was 1 micron or less, and dried at 80°C for 10 minutes.
Form a charge generation layer.

The eutectic complex was then obtained by contacting this layer with methylene chloride vapor for several minutes.

Next, a 25% monochlorobenzene 1% solution of hydrazone having the structural formula (1) shown below and the above-mentioned polycarbonate as a binder mixed at a jlLm ratio of 1:1 was dried on the charge generation layer using a Meyer bar. A charge transport layer is formed by coating to a thickness of 12 microns. What's more?
Sample 1 was prepared using the same method.

On the other hand, as a comparative sample, the following charge transport layer was laminated on the same charge generation layer as Sample 1.

That is, poly N-hinylcarbazole (trade name Lu
Bican M-170) 39 was dissolved in 30 CC (10 quintillion f%) of tetrahydrofuran, and then coated and coated. Coat it so that it is 12 microns,',a
A cargo transport layer was formed and used as Comparative Sample 1.

0) Electrophotographic A-a light body made from a fang is used as an electric machine■
Electrostatic copying paper test was charged dynamically using a Model I 5P-428 device, held for 1 second in a dark place, and then exposed to light for 4 seconds at an illuminance of 5 lux.
Check out ft'll students.

As for the charging characteristics, the surface potential and the amount of trend X (E
1/,) was measured.

Furthermore, as a simple way to express the optical memory effect, a sample that has been subjected to the above measurement once is irradiated with a 6001 ux fluorescent lamp for a minute, then left in a dark place for 1 minute. Let it be represented by the potential difference ΔV1 from the first time. It can be said that the larger the value of ΔV1, the greater the optical memory effect.

One-quadrift mobility is measured using the usual Time off1
= 咥－(Multiple ζ Therefore h becomes to znarichi As mentioned above, create V ko/this test, 1-・10 hearts 1dt・, ζ Wakainashi・9
Apply the upper nesar rt pole, and this and aluminum cum
/E ``Continue adding +-uJ: [LF, q) to negative value and aluminum to positive value at a certain time so that C can be obtained.

Irradiate 7 with original pulse, 667 fertilizer of nitrogen laser (Todo α Nakabatake 5 ηsec)\Iroto H℃, therefore 5 soQn
in9 has changed.knesa;ti! Yo 10 or 15
Teru dJ f, ta. Time sequence (d) First, an electric field of 2.5 x 105 V/cm was applied between the above sample electrodes for about 2 seconds, and after the pressure impression U[] f15, 1.:% #hill, 1 and then radar d. '-Irradiate the light beam ξ'r-0 that J temple (
Koi'1li) Reru, Tooru, Heat/dγ: From Bikonosugi, Geariya's running? Determine the time tτ and calculate 1 of μd from μc%=d/lτE. Calculate i to E here, = ;;% l
'2.5 in J ml>(i 1l15V/rrn, a
f'J trial)'s film, glue, and get wet.

Next, the impression of "-"(:'1°11. for in<.
4J) 9 and (IIA's IIA of 17) are shown.

Sample 1 600 5.3 0 1.2XiO-5
Comparative wipe 1-600 23.0 -175
3.8Kari 0-7 From these results, the value of μd is 10
It can be seen that if z2/v, soc or higher, the sensitivity is high and at the same time the optical memory effect becomes small. Both of the twisted charge generation layers are eutectic complexes, but it can be seen that the charging characteristics are greatly influenced by the selection of the charge transport layer. At this point, the value of drift mobility depends on the charge-generating material and ? , it has been demonstrated that this provides useful information for the selection of shipping charges.

Example 2 Disazo pigment (2) 59 having the following structure and 2 butyral resins (butyralization degree: 63 molar) were dispersed together with a solution of 95% ethanol, then coated on an aluminum sheet and dried. A charge generation layer having a subsequent thickness of 0.08 microns was formed.

Next, hydrazo/ of structural formula (3) and styrene-acrylic resin as a binder (product name Nippon Steel Chemical Exhibition MS-2
00) in an IT ratio of 5:1, and then apply a monochlorhenicine 20 Rinya 56 Yakushin on the charge generation layer using a Mayano coating to give a dry film thickness of 20 microns. How many layers are there?

l Try the one made in this way; 4-! It was set as +2.

- As a comparison sample, a charge generation layer was formed using a different pigment in the lateral part from that of sample 2.

In other words, the structure below is 4.1
9 and C, cyclohexibunone 18. '+9 and Gasis Heath 20atJ were dispersed for 4 hours using 1 knife and 1 inch gamma hill.

To this dispersion, 4.4 I of a solution of polyvinyl butyral (trade name: BM-2, manufactured by Block Chemical Co., Ltd.) with a weight ratio of 91 to methyl ethyl ketone:cyclohexanone as a binder was added as a binder.
Add another 2 hours of red devil dispersion. This dispersion was coated onto an aluminum sheet using a Mayer Parr so that the dry film thickness would be 0.2 microns to form a charge generation layer.

Next, a 2% by weight solution of monochlorobenseno, which is a mixture of the same charge transport material (3) as in sample 2 and a styrene-acrylic resin as a binder at an M ratio of 1:1, was dried with a Meyer bar. The coating was applied so that the film thickness was 12 microns. The sample produced in this manner is referred to as Comparative Sample 2.

The samples prepared as described above were subjected to measurements in exactly the same manner as in Example 1, and the following results were obtained.

Sample 2-61 6, Q +5 1.0X10-ri Comparison sample 2 -600 7.5 -95
In the case of 2.8 By combining the originals, 7 was able to create a photoreceptor with high sensitivity and at the same time a small optical memory effect.

Patent applicant: Canon Co., Ltd.

Claims (1)

[Claims] (1) In a negatively charged electrophotographic photoreceptor in which a charge generation layer is provided on a tetraelectric support and a charge transport layer is further provided on this, the holes in the two-layer system are
1. A laminated electrophotographic photoreceptor characterized by using an organic photoconductive compound having a drift mobility of 10 6 n2/v, sec or more.