JPH04304460A - Positive chargeable photosensitive body - Google Patents

Abstract

PURPOSE:To improve electrophotographic characteristics and to prevent the generation of image defects, adhesion defects, etc., by providing a photosensitive layer of single layer constitution contg. a carrier generating material and carrier transfer material directly on a base body which is not subjected to machining. CONSTITUTION:The photosensitive layer 2 of the single layer constitution contg. the carrier generating material 3 and the carrier transfer material 4 is directly provided on the base body 1 which is not subjected to machining. The weight ratio P of the carrier generating material 3/binder resin in the photosensitive layer 2 is preferably 0.3<=P<=2.0. The average depth Rp of the surface roughness of the base body 1 which is not subjected to machining is preferably >=0.5mum and the max. height Rmax is preferably <= 5mum. The production cost of the photosensitive body is reduced and the moire troubles at the time of image formation are eliminated by using the base body 1 having such original surface. The coating itself is stabilized and the good image quality free from the defects is obtd. by increasing the thickness of the coated layer. The repetitive characteristics, and the adhesiveness of the layer are thus improved.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positively charging electrophotographic photoreceptor comprising a single-layer organic photoconductive photosensitive layer provided on a substrate.

0002

BACKGROUND OF THE INVENTION After the development of electrophotography, the scope of research for photoconductive materials used in photoreceptors has been expanded from inorganic to organic photoconductive materials (PCM), and carrier generation,
The photoconductive function of carrier transport is caused by carrier-generating substances (
The layer structure of the photoconductive layer (photosensitive layer; PCL) has been improved based on carrier behavior analysis, and the binder resin used for layer formation has also been improved. Pioneering research is being actively conducted.

[0003] After these technological improvements made it possible to use plain paper as a transfer material, the electrophotographic copying method quickly became popular, suitable for mass use, improved performance, durability,
There is a growing demand for improvements in running costs, especially consideration of environmental hygiene during use.

On the other hand, the mainstream of PCMs that have been put into practical use to date are those for negative charging, but negative charging due to corona discharge generates 5 to 10 times as much ozone as positive charging, and deterioration due to high concentration of ozone occurs. This becomes noticeable and poses a problem in terms of durability.

Furthermore, due to the increased frequency of use, the amount of ozone emitted from copying machines has become a problem in terms of working environment and hygiene, but as mentioned above, the negative charging method in principle generates a large amount of ozone, making it difficult for environmental measures. It doesn't suit me.

Therefore, the positive charging method is attracting attention, but the conventional P
CM (CGM) has sensitivity, chargeability,
Still unsatisfied with ozone resistance etc.

The layer structure of PCL applied to the positive charging method is a single layer type, a CTL/CGL/substrate type in which a carrier transport layer (CTL) is stacked on a carrier generation layer (CGL), or a reverse type CGL/ Although either a CTL/substrate type or a laminated type can be constructed, since it is difficult to obtain a high-performance n-type CTM, a single layer type and a CGL/CTL/substrate type are convenient.

However, in this case, since CGL and CGM are poor in durability and durability on the surface of PCL, they are susceptible to chemical and mechanical problems such as ozone adsorption, thinning of the film, and formation of scratches, making it difficult to adjust performance. The durability of CGL, which is considered to be a thin layer, is extremely weak, and if you try to compensate for this shortcoming by adding a protective layer, the sensitivity and
This causes deterioration of the residual potential characteristics, and it is necessary to improve the binder.Many study results have been disclosed so far regarding binders, and among them, the excellent characteristics of polycarbonate and the like have been shown.

However, along with the demand for improved functionality to meet recent needs, there is a growing demand for inexpensive photoreceptors due to the widespread use of electrophotographic copying, and the need for simplification of the layer structure and simplification of substrate processing is increasing. It is being

As the material for the substrate for electrophotography, metal materials such as aluminum, copper, brass, steel, stainless steel, and other plastic materials molded into a belt or drum shape are used. Among these, aluminum is preferably used due to its excellent cost and workability, and thin-walled cylindrical aluminum tubes usually extruded or pultruded are often used. As for the above-mentioned molding, efforts have been made to improve the molding method and forming means to obtain raw pipes with high surface precision, but due to the precision of the molding machine and the presence of metal powder, dust, etc. The surface roughness (Rmax) of the material reaches several micrometers, and deep scratches often occur, especially due to the presence of metal powder or the like. Therefore, it is common to apply finishing processing such as mirror finishing using a diamond cutting tool or the like to form an intermediate layer of 0.1 to 2 .mu.m, and then provide a photosensitive layer thereon.

Formation of such a thin layer is difficult to process due to production technology, difficult to process uniformly, and may cause scratches, irregularities, etc. on the surface of the substrate.
Substrate defects such as dust are not always sufficiently covered, and image defects such as streaks, pinholes, and black spots are likely to occur during image formation.

Therefore, it is necessary to give the substrate surface a mirror finish using, for example, a diamond bite, strengthen cleaning to ensure a clean surface, and require precise coating processing, which increases the cost when manufacturing the photoreceptor. is inviting.

[0013]

OBJECTS OF THE INVENTION The objects of the present invention are to provide high productivity, good adhesion of the photosensitive layer to the substrate, and high sensitivity without decrease in residual potential during image formation and fatigue deterioration during repeated use.
Moreover, it is an object of the present invention to provide a low-cost positive charging photoreceptor.

[0014]

[Structure of the Invention] The object of the present invention is to provide a single-layered photosensitive layer containing a carrier-generating substance and a carrier-transporting substance directly on a substrate that is not subjected to cutting processing (hereinafter referred to as a plain substrate). This is achieved by using a positive charging photoreceptor.

In an embodiment of the present invention, the weight ratio P of carrier generating substance/binder resin in the photosensitive layer is;
It is preferable that 3≦P≦2.0.

If P is less than 0.3, sensitivity and chargeability will decrease, and residual potential will increase; if it exceeds 2.0, dark decay and acceptance potential will decrease, resulting in poor durability such as printing durability. It lacks.

Furthermore, regarding the surface roughness of the plain substrate, the average depth Rp of the roughness curve is 0.5 μm or less, and the maximum height Rm
It is preferable that ax is 5 μm or less.

The range of surface roughness of the substrate defined in the present invention is determined based on the JIS surface roughness (BO601).

FIG. 1 shows the roughness curve of a plain substrate, where L is the reference length in the average direction, h is the center line, and Rp is the height from the center line h to the maximum peak within the reference length L. However, according to the definition, it is the depth from the straight line passing through the top of the largest mountain and parallel to the average direction (i.e., the outer contour line of the surface) to the center line. Also, d is the depth from the center line h to the maximum valley within the reference length L, Rma
x represents the elevation from the deepest valley to the highest peak; Rp+d, and is referred to as the maximum height of the roughness curve. In the substrate according to the present invention, the roughness is restricted to Rp of 0.5 μm or less and Rmax of 5 μm or less.

[0020] The roughness curve is calculated by cutting off the waviness component of the surface shape from the cross-sectional curve of the surface that appears on the cross-sectional plane of the plain substrate, and calculating the surface unevenness with the x-axis of the average direction straight line as a reference. This is a curve obtained by rearranging the curve to make it uneven, and if this is y, it can be expressed as y=f(x). In addition, in order to see the degree of deviation of the unevenness from the contour line of the surface, the roughness curve when the x-axis is taken as the contour line is y'=f'(x)
Then, the center line h and the average depth Rp as a linear function
teeth;

[0021]

[Math 1]

It can be found as follows. Here, h and Rp occupy the same position.

Note that the distance f(
The quotient obtained by dividing the absolute value of |f(x)-h| between 0 and L by the reference length L is distinguished as the centerline average roughness Ra.

To measure the roughness curve, a surface roughness measuring instrument incorporating an optical stylus pickup E-DT-SL204 was used.
manufactured by Tokyo Seimitsu) etc. are used.

In the present invention, the photosensitive layer is formed on the substrate having the above-mentioned surface roughness with a thickness of 10 to 200 μm, preferably 20 μm.
The coating liquid is provided at a thickness of 100 μm to cover defects in the substrate due to the anchoring effect caused by wetting and penetration of the coating liquid into the concave portions of the substrate, thereby improving adhesion between the substrate and the photosensitive layer (PCL). R
If p, Rmax exceeds the above threshold, it may not be possible to eliminate surface irregularities.

[0026] If the average depth Rp of the substrate exceeds 0.5 μm, for example, the parts of the substrate molding machine, especially the machined surfaces of dies, etc., are already worn to the extent that they are no longer practical, and therefore need to be replaced. If Rmax exceeds 5 μm, for example, metal powder and dust are firmly attached to the die and must be cleaned and removed.

To form PCL on the substrate according to the present invention, the molded substrate is treated with a solvent such as alcohol, acetone, methyl ethyl ketone, ethyl acetate, or triclane, and if necessary, an ultrasonic cleaner or the like is used. and wash thoroughly.

[0028] After cleaning, the prepared PCL coating liquid is applied onto the substrate by a coating method such as dip coating, spray coating, spin coating, or blade coating so that the film thickness after drying is 10 to 200 μm. do it.

[0029] It is preferable that the CGM used in the monolayer structure and positive charging photosensitive layer of the present invention has an electron-withdrawing group,
As a result, the electron transport ability in the layer becomes sufficient, and when positively charged, electrons move quickly to the positively charged surface of the photoreceptor, resulting in high photosensitivity and low residual potential. On the other hand, if it does not have an electron-withdrawing group, it will have poor electron transport ability, and its photosensitivity and residual charge characteristics will deteriorate. That is, in general, when a mixed-phase PCL containing CGM and CTM is irradiated with light as a photoreceptor for positively charging, the surface positive charges are attenuated to a certain extent, but there is a tendency that the attenuation is not sufficient beyond that. However, when the CGM used in the present invention has a photoreceptor having a PCL consisting of the CGM alone and is negatively charged, the electron transfer rate in the layer is higher than when it is positively charged (that is, the photosensitivity is higher when negatively charged). Therefore, electrons generated by light irradiation after positive charging of the photoreceptor having the above-mentioned mixed phase PCL move to the surface at high speed, thereby sufficiently attenuating the surface positive charge (the photosensitivity is improved and the residual (The potential also becomes smaller).

On the other hand, it is preferable that the CTM used in the present invention has a property that allows the holes to move easily.
In combination with the properties of CTM described above, it is possible to use the photoreceptor with positive charging.

In the present invention, if an electron-accepting substance or a Lewis acid, which will be described later, is added to PCL, a charge transfer complex is formed, so that the sensitizing effect can be further improved.

The CGM used in the present invention has the following general formula [
Bisazo compounds of group BA] and polycyclic quinone compounds of general formula [PQ] are preferred.

[0033]

[Chemical formula 1]

In the general formula [BA], Ar1, Ar2 and A
r3 is a substituted or unsubstituted carbocyclic aromatic ring group, R1 and R2 are each an electron-withdrawing group or a hydrogen atom, and at least one of R1 and R2 is an electron-withdrawing group such as a cyano group. , in A, X is a hydroxy group, -N
(R4)R5, -NHSO2-R6 (However, R4 and R5
are each a hydrogen atom or a substituted or unsubstituted alkyl group, R6 is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group), Y is a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, a carboxyl group, a sulfo group, a substituted or unsubstituted carbamoyl group, or a substituted or unsubstituted sulfamoyl group (however, when l is 2 or more, mutually different groups may be used), Z is a substituted or an atomic group necessary to constitute an unsubstituted carbocyclic aromatic ring or a substituted or unsubstituted heterocyclic aromatic ring, R3 is a hydrogen atom, a substituted or unsubstituted amino group, a substituted or unsubstituted Carbamoyl group, carboxyl group or its ester group, A' is
In the substituted or unsubstituted aryl group, k is an integer of 1 or 2, and l is an integer of 0 to 4.

In addition to the above-mentioned bisazo compounds, monoazo compounds having the above-mentioned electron-withdrawing groups in the molecule, other bisazo compounds, and polyazo compounds may also be used.

As specific examples of azo compounds that can be used in the present invention, those listed in JP-A-61-48861, page 4, lower left column to page 8, upper right column, may be cited.

[0037]

[Chemical 2]

In the general formula [PQ], X represents a halogen atom, a nitro group, a cyano group, or a carboxyl group, and n is 1 to
An integer of 4, m represents an integer of 1 to 6.

As specific examples of the polycyclic quinone compounds, those listed in the lower right column on page 8 to the upper left column on page 10 of JP-A-61-48861 are cited.

Carrier transport substances used in the present invention include oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiasiazole derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, imidazolidine derivatives, bisimidazolidine derivatives, styryl compounds, and hydrazone compounds. , pyrazoline derivatives, oxazolone derivatives, benzothiazole derivatives, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives,
Acridine derivatives, phenazine derivatives, aminostilbene derivatives, poly-N-vinylcarbazole, poly-1-
It may be vinylpyrene, poly-9-vinylanthracene, etc.

More preferred carrier transport substances include:
Styryl compounds represented by the following general formulas [ST-1], [ST-2], general formulas [HA-1], [HA-2], [
HA-3] and [HA-4], pyrazoline compounds represented by the general formula [PA], and amine derivatives represented by the general formula [AM].

[0042]

[Chemical formula 3]

In the general formula [ST-1], R1,
R2 represents a substituted or unsubstituted alkyl group or aryl group, and as the substituent, an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a halogen atom, or an aryl group is used. Ar1 and Ar2 represent a substituted or unsubstituted aryl group, and the substituent used is an alkyl group, an alkoxy group, a substituted amino group, a hydroxyl group, a halogen atom, or an aryl group. R3 and R4 represent a substituted or unsubstituted aryl group or a hydrogen atom, and substituents include an alkyl group, an alkoxy group,
A substituted amino group, hydroxyl group, halogen atom, or aryl group is used.

In the general formula [ST-2], R5 is a substituted or unsubstituted aryl group, and R6 is a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, an alkoxy group, an amino group, a substituted amino group, or a hydroxyl group. , R7 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group.

[0045] The above general formula [ST-1] or [ST-2]
As a specific example of the styryl compound represented by
-48861, those listed in the lower right column on page 10 to the lower left column on page 15 or the lower right column on page 15 to the lower left column on page 17 are incorporated.

[0046]

[C4]

[0047]

[C5]

In the general formula [HA-1], R1 and R2 are each a hydrogen atom or a halogen atom, R3 and R4 are each a substituted or unsubstituted aryl group, and A
r represents a substituted or unsubstituted arylene group.

In the general formula [HA-2], R5 is a methyl group, an ethyl group, a 2-hydroxyethyl group, or a 2-hydroxyethyl group.
Chlorethyl group, R6 represents a methyl group, ethyl group, benzyl group or phenyl group, R7 represents a methyl group, ethyl group, benzyl group or phenyl group.

In the general formula [HA-3], R8 is a substituted or unsubstituted naphthyl group; R9 is a substituted or unsubstituted alkyl group, aralkyl group, or aryl group; R
10 is a hydrogen atom, an alkyl group, or an alkoxy group; R11
and R12 are the same or different groups consisting of a substituted or unsubstituted alkyl group, aralkyl group, or aryl group.

In the general formula [HA-4], R13
is a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, R14 is a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group,
Q represents a hydrogen atom, a halogen atom, an alkyl group, a substituted amino group, an alkoxy group, or a cyano group, and p represents an integer of 0 or 1.

These general formulas [HA-1] to [HA-4
] Specific examples of hydrazone compounds include JP-A-61-4
Those listed in the upper left column on page 19 to the upper left column on page 27 of No. 8861 are incorporated.

[0053]

[C6]

In the general formula [PA], l is 0 or 1, R1, R2 and R3 are substituted or unsubstituted aryl groups, R4 and R5 are hydrogen atoms, alkyl groups having 1 to 4 carbon atoms, or substituted or an unsubstituted aryl group or aralkyl group (However, R4 and R5 are not hydrogen atoms, and when l is 0, R4 is not a hydrogen atom.)
As specific examples of the pyrazoline compound represented by the general formula [PA], those listed in the upper right column on page 27 to the upper right column on page 28 of JP-A-61-48861 are cited.

In the general formula [AM], Ar1, A
r2 represents a substituted or unsubstituted phenyl group, and the substituent used is a halogen atom, an alkyl group, a nitro group, or an alkoxy group. Ar3 represents a substituted or unsubstituted phenyl group, naphthyl group, anthryl group, fluorenyl group, or heterocyclic group, and substituents include an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, an aryloxy group, an aryl group, an amino group, Nitro groups, piperidino groups, morpholino groups, naphthyl groups, anthryl groups and substituted amino groups are used. However, an acyl group, an alkyl group, an aryl group, or an aralkyl group is used as a substituent for the substituted amino group.

Specific examples of the amine derivative represented by the general formula [AM] include those described in JP-A No. 61-48861, No. 2
Those listed in the lower right column on page 8 to the lower left column on page 30 are incorporated.

Binder materials usable in the present invention:
In particular, binder resins include polyethylene, polypropylene, acrylic resin, methacrylic resin, vinyl chloride resin, vinyl acetate resin, epoxy resin, polyurethane resin, phenol resin, polyester resin, alkyd resin, polycarbonate resin, silicone resin, melamine resin, etc. Addition polymer resins, polyaddition resins, polycondensation resins, and copolymer resins containing two or more repeating units of these resins, such as vinyl chloride-vinyl acetate copolymer resins, vinyl chloride-acetic acid Examples include insulating resins such as vinyl-maleic anhydride copolymer resins, and polymeric organic semiconductors such as poly-N-vinylcarbazole.

When the electrophotographic photoreceptor has a functionally separated single-layer structure, it is usually constructed as shown in FIG. FIG. 2 shows a structure in which a PCL 2 formed by dispersing CGM 4 made of the above-mentioned CGM in a layer containing the above-mentioned CTM 3 as a main component is provided directly on the conductive support 1 .

When the above CGM is dispersed in the form of particles to form a PCL, the CGM is preferably in the form of powder having an average particle size of 2 μm or less, preferably 1 μm or less. In other words, if the particle size is too large, dispersion in the layer will be poor, and some of the particles will protrude from the surface, resulting in poor surface smoothness. Toner particles tend to adhere and a toner filming phenomenon occurs easily. Long wavelength light (~700nm) as CGM
It is thought that the surface charge of those sensitive to CGM is neutralized by the generation of thermally excited carriers within the CGM, and the larger the particle size of the CGM, the greater this neutralization effect. Therefore, high resistance and high sensitivity can only be achieved by reducing the particle size. However, if the above grain size is too small, it tends to aggregate, which increases the resistance of the layer, increases crystal defects and reduces sensitivity and repeatability, or there is a limit to miniaturization. It is desirable that the lower limit of the diameter is 0.01 μm.

Organic amines can be added to the PCL of the present invention for the purpose of improving the carrier generation function of CGM, and it is particularly preferable to add a secondary amine.

Examples of such secondary amines include dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, diisobutylamine, diamylamine, dihexylamine, diisohexylamine, dipentylamine, diisopentylamine, dioctylamine, Examples include diisooctylamine, dinonylamine, diisononylamine, didecylamine, diisodecylamine, dimonodecylamine, diisomonodecylamine, didodecylamine, diisododecylamine, and the like.

[0062] The amount of organic amines added is as follows:
The amount of CGM is equal to or less than CGM, preferably 0.2
The number of moles is preferably in the range of 0.005 times to 0.005 times.

Further, in the PCL of the present invention, an antioxidant can be added for the purpose of preventing ozone deterioration.

Typical examples of such antioxidants are shown below, but the invention is not limited thereto.

Group (1): Hindered phenols dibutylhydroxytoluene, 2,2'-methylenebis(6-
t-butyl-4-methylphenol), 4,4'-butylidenebis(6-t-butyl-3-methylphenol)
, 4,4'-thiobis(6-t-butyl-3-methylphenol), 2,2'-butylidenebis(6-t-butyl-4-methylphenol), α-tocopherol, β
-tocophenol, 2,2,4-trimethyl-6-hydroxy-7-t-butylchroman, pentaerythyltetrakis [3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 1 , 6-hexanedi-rubis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], butylhydroxyanisole, dibutylhydroxyanisole, 1-[2
-{(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy}ethyl]-4-[3-
(3,5-di-t-butyl-4-hydroxyphenyl)
propionyloxy]-2,2,6,6-tetramethylpiperidyl and the like.

Group (2): paraphenylenediamines N-
Phenyl-N'-isopropyl-p-phenylenediamine, N,N'-di-sec-butyl-p-phenylenediamine, N-phenyl-N-sec-butyl-p-phenylenediamine, N,N'-dimethyl- N,N'-ji-
t-butyl-p-phenylenediamine, etc.

Group (3): Hydroquinones 2,5-di-
t-octylhydroquinone, 2,6-didodecylhydroquinone, 2-dodecylhydroquinone, 2-dodecyl-5-chlorohydroquinone, 2-t-octyl-5
-Methylhydroquinone, 2-(2-octadecenyl)
-5-methylhydroquinone, etc.

Group (4): Organophosphorus compounds dilauryl-3
, 3'-thiodipropionate, distearyl-3-3
'-thiodipropionate, ditetradecyl-3,3'
- Thiodipropionate, etc.

These compounds are known as antioxidants for rubber, plastics, oils and fats, and are easily available commercially.

The amount of antioxidant added is 0.1 to 100 parts by weight (0.1 to 100% by weight), preferably 1 to 50% by weight, particularly preferably 5 to 2 parts by weight, based on 100 parts by weight of CTM.
5% by weight.

Next, as the conductive support for supporting the PCL, a metal plate made of aluminum, nickel, etc., a metal drum, or a metal foil laminated, or aluminum,
A plastic film coated with tin oxide, indium oxide, etc., or a paper or plastic film coated with a conductive substance, or a drum can be used.

[0072] In the present invention, PCL is typically prepared by dipping, spray coating, or dispersing a dispersion of the CGM or CTM according to the present invention described above in a suitable dispersion medium or solvent alone or together with a suitable binder resin. It can be provided by a method of directly coating the substrate by blade coating, roll coating, etc. and drying it.

Examples of the dispersion medium used in the present invention include hydrocarbons such as hexane, benzene, toluene, and xylene; methylene chloride, methylene bromide,
2-dichloroethane, sym-tetrachloroethane, c
Halogenated hydrocarbons such as is-1,2-dichloroethane, 1,1,2-trichloroethane, 1,2-dichloropropane, chloroform, bromoform, chlorobenzene;
Ketones such as acetone, methyl ethyl ketone, and cyclohexanone; Esters such as ethyl acetate and butyl acetate; Alcohols such as methanol, ethanol, propanol, butanol, cyclohexanol, heptanol, ethylene glycol, methyl cellosolve, ethyl cellosolve, and acetic acid cellosolve. and derivatives thereof; ethers and acetals such as tetrahydrofuran, 1,4-dioxane, furan, and furfural; amines such as pyridine, butylamine, diethylamine, ethylenediamine, and isopropanolamine; nitrogen such as amides such as N,N-dimethylformamide One or more compounds such as fatty acids, phenols, sulfur and phosphorus compounds such as carbon disulfide and triethyl phosphate can be used.

In the present invention, PCL may contain one or more electron-accepting substances for the purpose of improving sensitivity, reducing residual potential or fatigue during repeated use, etc. Examples of electron-accepting substances that can be used here include succinic anhydride, maleic anhydride, dibromide anhydride, maleic acid, phthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, 3-nitrophthalic anhydride, 4-nitrophthalic anhydride, pyromellitic anhydride,
Mellitic anhydride, tetracyanoethylene, tetracyanoquinodimethane, o-dinitrobenzene, m-dinitrobenzene, 1,3,5-trinitrobenzene, paranitrobenzene, picryl clide, quinone chlorimide, chloralyl, brumanil, dinitrobenzene Chlordicyanoparabenzonone, anthraquinone, dinitroanthraquinone, 2,7
-Dinitrofluorenone, 2,4,7-trinitrofluorenone, 9-fluorenylidene [dicyanomethylenemalonodinitrile], polynitro-9-fluorenylidene-[dicyanomethylenemalonodinitrile], picric acid, o-nitrobenzoic acid, p- Nitrobenzoic acid, 3,5-
Examples include dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, phthalic acid, mellitic acid, and other compounds with high electron affinity. In addition, the addition ratio of the electron-accepting substance is
Perylene derivative of the present invention:electron-accepting substance=1 by weight
00:0.01~200, preferably 100:0.1~
It is 100.

The photoreceptor of the present invention may also contain an ultraviolet absorber and a dye for color sensitivity correction, if necessary, for the purpose of protecting the PCL.

[0076]

[Examples] Next, the present invention will be explained in detail with reference to Examples.

As the layer structure of the photoreceptor, the layer structure shown in FIG. Examples 1 to 8 and Comparative Example (
1) to (6) are prepared, normal temperature and humidity (NN), high temperature and high humidity (NN),
Potential characteristics (VH, VL) and image quality under low temperature and low humidity (LL) environments were evaluated.

(1) Preparation of Substrate An aluminum tube having the surface roughness characteristics shown in Table 1 and having a diameter of 60.6 mm was used. The aluminum tube is first hot-formed using a direct extrusion molding machine to create a crude aluminum tube, and then the crude aluminum tube is cold-drawn using a pultrusion molding machine to improve dimensional accuracy and become an aluminum tube. The latter process is usually called ioning process. (2) Formation of PCL 20g of the following CGM and polycarbonate Z-
A coating solution was prepared by mixing, dissolving and dispersing 200 "Mitsubishi Gas Chemical Co., Ltd." (20 g) in 1 liter of methyl ethyl ketone.

Further, 140 g of the following CTM and 230 g of polycarbonate Z-200 (manufactured by Mitsubishi Gas Chemical Co., Ltd.) were mixed and dissolved in 1 liter of dichloroethane to prepare a coating solution, and the above solutions were mixed to prepare a coating solution. This coating liquid was coated onto the substrate to a thickness of 20 μm to obtain a photoreceptor.

[0080]

[Table 1]

[0081]

[C7]

[0082]

[Chemical formula 8]

[0083]

[Chemical formula 9]

[0084]

[Chemical formula 10]

(Test conditions and evaluation) The photoreceptor was used in a laser printer "Lp-301" manufactured by Konica Corporation.
5” is installed on a modified machine, at room temperature and humidity (20°C, 50% RH).
; NN), high temperature and high humidity (33°C, 80% RH; HH) and low temperature and low humidity (10°C, 20% RH; LL) atmospheres,
Photoreceptor potential -600±10(v), development bias -48
0(v), a running test of up to 10,000 times was performed under the conditions of a single-component magnetic developer exclusively used for "Lip-3015", and image quality changes (especially black spots and fogging) obtained due to potential fluctuations and reversal development were observed. Check the results in Table 2 (1), (2)
It was shown to.

[0086]

[Table 2]

[0087]

[Table 3]

In the table, VH is the potential of the unexposed area, and VL is the potential of the exposed area.

[0089] For the evaluation of black spots in the evaluation of inversion image quality, the image analysis device "Ominicon 3000" (manufactured by Shimadzu Corporation) was used.
Measure the particle size and number of black spots using φ (diameter) 0.0
Judgment was made based on the number of black spots of 5 mm or more per cm2.

The criteria for evaluating black spots are shown in Table 3. The fog density was read using a PDP-65 densitometer (manufactured by Konica Corporation).

[0091]

[Table 4]

It should be noted that if the black spot determination result is up to △, it is practical, but if it is ×, it is not suitable for practical use.

From Table 2, the photoreceptors of the present invention are NN, HH,
It can be seen that under both conditions of LL, the initial and post-running potential fluctuations are smaller than the comparative photoreceptor, and the occurrence of black spots and fogging is extremely small.

[0094]

[Effect of the invention] By using a bare substrate,
The manufacturing cost of the photoreceptor has been reduced, and the problem of moiré during laser image formation has been eliminated.

Furthermore, since the coating layer was thickened, the coating itself became stable and easy, and surface defects were completely covered with a uniform layer.
Good image quality with no defects can be obtained.

[0096] Further, the repeatability regarding residual and charging potential was good, the sensitivity was high, and the adhesion of the layer was further improved.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a roughness curve of a cross section of a substrate, and FIG. 2 is a cross-sectional view showing a layer structure of a photoreceptor according to an example.

[Explanation of symbols]

1...Base 2...Photosensitive layer 3...Carrier transport substance 4...Carrier generating substance

Claims (3)

[Claims] 1. A photoreceptor for positive charging, characterized in that a photoreceptor layer having a single layer structure containing a carrier-generating substance and a carrier-transporting substance is provided directly on a substrate that is not subjected to cutting processing. 2. The photoreceptor for positive charging according to claim 1, wherein the weight ratio P of carrier generating substance/binder resin in the photosensitive layer is: 0.3≦P≦2.0. 3. The surface roughness according to claim 1 or 2, wherein the average depth Rp of the roughness curve is 0.5 μm or less and the maximum height Rmax is 5 μm or less in the surface roughness of the substrate that is not subjected to cutting. Photoreceptor for charging.