JPH0337662A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain stable high gamma-light attenuating characteristics at the time of repeated use by using specified titanylphthalocyanine as a carrier generating material, specifying the ratio of a carrier transferring material to a resin binder and incorporating an antioxidant. CONSTITUTION:When a photosensitive layer 2 contg. a carrier generating material, a carrier transferring material and a resin binder is formed on a substrate 1, titanylphthalocyanine having such a crystal form that the X-ray diffraction spectrum to Cu-Kalpha rays having 1.541Angstrom wavelength has intense peaks at 9.6 deg. and 27.2 deg. of Bragg angle 2theta is used as the carrier generating material. The carrier transferring material is contained by 0-30wt.% per 100wt.% of the resin binder and an antioxidant is incorporated. Stable high gamma-light attenuating characteristics at the time of repeated use are obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a photoreceptor, particularly an electrophotographic photoreceptor.

[Prior art]

Photoreceptors using organic photoconductive substances (OPC) are generally less toxic than inorganic photoconductive substances, and are advantageous in terms of flexibility, lightness, film formability, cost, etc. , has been attracting attention recently.

In such electrophotographic photoreceptors, functionally separated photoreceptors, which use materials with separate charge generation and transport functions, allow each of these functions to be designed independently, and the selection can be made in the photoreceptor design. It is advantageous in that the width is expanded, and as a result, the electrophotographic characteristics can be improved, and it is excellent in terms of sensitivity, repeatability, mechanical strength, etc.

Such electrophotographic photoreceptors are generally widely used in electrophotographic copying machines, printers, and the like. For example, in copying machines, photoreceptors that are sensitive to visible light sources have been developed.
On the other hand, a printer using a semiconductor laser as a light source is used at the end of the computer. The electrophotographic photoreceptor installed in the printer must have high sensitivity in the near-infrared region.

Further, progress is being made in the development of a printer that uses a semiconductor laser and has a copying function using white light as a light source.

In this case, the photoreceptor must first have high sensitivity in the near-infrared region in order to adapt to the printer function, and high sensitivity to light in the visible light region in order to adapt to the copying function. That is, there is a demand for the development of a composite electrophotographic photoreceptor that can be applied to an apparatus having both the printer function and the copying function using white light as a light source as described above.

For example, JP-A-47-37543, JP-A-55-2283
Photoreceptors containing bisazo compounds, which are already known from No. 4, No. 54-79632, No. 56-116040, exhibit relatively good sensitivity in the short and medium wavelength ranges, but have poor sensitivity in the long wavelength range. Due to its low sensitivity, it could not be used in laser printers that use semiconductor light sources.

The currently widely used gallium-aluminum-arsenide (Ga-A(2-As)) light emitting device has an oscillation wavelength of 750 nm.
As an organic photoreceptor having sensitivity in such a long wavelength region, for example, r, r, ・99. / type metal phthalocyanine compounds.

Furthermore, the α-type titanyl phthalocyanine described in JP-A No. 61-239248, the β-type titanyl phthalocyanine described in JP-A-62-67094, and m reported in the Journal of Electrophotography, Vol. 27, No. 4 (p. 19-24). type titanyl phthalocyanine, etc.

On the other hand, the light attenuation curve of a photoreceptor that is suitable for printer functions is insensitive to low illuminance, with little charge attenuation in the low exposure range, forming a flat plateau, and cutting off sharply from a certain exposure range. Preferably, the decay curve is of the descending, high-gamma type.

In other words, charge is lost due to low illuminance areas at the edges of the image that occur due to light diffraction on the image exposure surface, typically in the rising area of the exposure intensity that approaches the image in dot exposure, and the tail light in the falling area at the end of the image. It is preferable that sharp rises and falls of charges occur at the peripheral edge of the image without causing a sharp rise and fall of charge, thereby providing a sharp image.

Photoreceptors used in electrophotography include those that exhibit high γ type light attenuation characteristics as described above, and those that exhibit sharp light attenuation from low illuminance and slow light attenuation until reaching the end point of light attenuation. A certain so-called low γ
Some are known to exhibit type optical attenuation characteristics.

The above-mentioned materials exhibiting low γ type light attenuation characteristics have excellent gradation and repeatability, and are therefore suitable for repeat transfer type copying machines, etc., similar to selenium-based vapor-deposited photoreceptors exhibiting low γ type light attenuation characteristics. It is suitably used.

On the other hand, photoconductors exhibiting high γ-type light attenuation characteristics have steep light attenuation in the later stages of exposure and have high 7 characteristics, but the light attenuation curve changes and deteriorates during repeated use. It is not used effectively due to its drawbacks.

[Purpose of the invention]

Based on the above-mentioned circumstances, an object of the present invention is to provide a photoreceptor having high gamma light attenuation characteristics and which is stable even when used repeatedly. be.

[Structure and effects of the invention]

The object of the present invention described above is to provide a carrier-generating substance on a substrate,
In an electrophotographic photoreceptor provided with a photosensitive layer containing a carrier transporting substance and a binder resin, the carrier generating substance is
Bragg angle 2θ of X-ray diffraction spectrum for Cu-Ka line (wavelength 1.541A) is 9.6° and 27,2
It is a titanyl phthalocyanine having a strong peak at
It is distantly related to the electrophotographic photoreceptor, which is characterized by having an antioxidant content of 0 to 30 vt/it and containing an antioxidant.

In the aspect of the present invention, the peak intensity at Bragg angle 2θ of 9.6° of the titanyl phthalocyanine is 2.
Crystalline titanyl phthalocyanine having a peak intensity of 40% or more at 7.2° is preferred, and the antioxidant used is preferably one having a hindered phenol structural unit in its molecular structure.

In the configuration of the present invention, titanyl phthalocyanine has a property of giving a high γ type optical attenuation curve, and by restricting the content of the carrier transport substance, generated carriers are temporarily trapped and optical attenuation is suppressed. It is estimated that an avalanche phenomenon occurs all at once as the carriers become saturated, resulting in a sharp drop in the optical attenuation curve. Moreover, due to the effect of the antioxidant, even when dot-shaped images are repeatedly formed on a photoreceptor many times, excellent light attenuation characteristics exhibiting ultra-high gamma characteristics are stably exhibited. In particular, good results can be obtained when an antioxidant having a hindered phenol structural unit in its molecular structure is used.

FIG. 1 schematically shows preferable light attenuation characteristics obtained by the photoreceptor of the present invention, where vo is the charging potential (V), V,
is the initial potential (V), E, before exposure. is the amount of laser beam irradiation (μJ/c+a”) required for the initial potential ■□ of the unexposed area to attenuate to 90%, Es.

represents the amount of laser beam irradiation (μJ/am'') required for the initial potential V)l to attenuate to 50%.

Especially E. and E. However, it is preferable that the following formula is satisfied.

R-E*. /(E,.-E,.)≧1.5 Also, the initial potential 1v□1 is preferably in the range of 600 to 2000V.

The present invention will be specifically explained below.

The basic structure of the titanyl phthalocyanine of the present invention is represented by the following general formula (Pc).

- Form power (Pc) However, X 1. X! , X 3. X 4 represents a hydrogen atom, a halogen atom, an alkyl group, or an alkoxy group, and n, m, 12. represents an integer from O to 4.

The above X-ray diffraction spectrum is a reflection diffraction spectrum measured under the following conditions. (Using 320 type self-recording spectrophotometer (Hitachi Manufacturing Department)) X-ray tube Cu Voltage 40. OKV current
100 m A start angle
6.00 deg.

Stop angle 35.00 deg.

Step angle 0.020 deg.

Measurement time: 0-50 sec.

The titanyl phthalocyanine according to the present invention (hereinafter referred to as Ti0Pc, limited to the product of the present invention) is produced, for example, by the following production method.

1. Mix 3-diiminoisoindoline and sulfolane, add titanium tetrapropoxide, and heat in a nitrogen atmosphere at 80-300°C, preferably 100-26°C.
React at 0°C. After the reaction is completed, the mixture is allowed to cool and the precipitate is collected by filtration to obtain titanyl phthalocyanine.

As the apparatus used for the treatment, in addition to a general stirring apparatus, a homomixer, disperser, agitator, ball mill, sand mill, attritor, etc. can be used.

Note that the peak of Ti0Pc according to the present invention forms an acute-angled pyramidal projection that is clearly different from noise.

The X-ray diffraction diagram of Ti0Pc at Bragg angle 2θ is shown in Figure 2.
The absorption spectrum is shown in FIG. Ti0Pc has a large peak of absorption on the long wavelength side and a deep valley on the short wavelength side of the visible region.

This valley can be filled by selecting a preferred combination from known bisazo pigments, polycyclic quinone pigments, etc. that have spectral sensitivity in this wavelength range and using them together.

With this combination, high sensitivity can be maintained in a wide spectral range from long wavelengths to short wavelengths, and the potential history can be reduced even during repeated use.

According to this, it is suitable for copying machines that require main spectral sensitivity in the visible range (for example, image signals from fluorescent lamps, halogen lamps, xenon lamps, etc. - analog signals), and is suitable for use in the long wavelength side of the visible light range or in the infrared range. This makes it suitable for printers that require major spectral sensitivity (for example, light emitting diodes, gas lasers such as He-Ne lasers, image signals-digital signals of semiconductor lasers, etc.). In this sense, analog/
Both digital and digital formats can be realized.

Next, the carrier transport substance used in the present invention is not particularly limited, but includes, for example, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidasilone derivatives, imidazolidine derivatives, bisimidazolidine. derivatives, styryl compounds, hydrazone compounds, pyrazoline derivatives, amine derivatives, oxacilone derivatives,
benzothiazole derivatives, bayzimidazole derivatives,
One or more types selected from quinazoline derivatives, benzofuran derivatives, acridine derivatives, phenazine derivatives, aminostin derivatives, poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene, etc. is exemplified.

Among these carrier transport substances, in addition to their excellent ability to transport carriers generated during light irradiation to the support side,
Those suitable for combination with TioPc and bisazo (BA) according to the present invention are preferred, and examples of such charge transport materials include those represented by the following general formulas (A), (B') and (C).

General formula (A) However, Ar', Ar'', and Ar' each represent a substituted or unsubstituted aryl group, Ar3 represents a substituted or unsubstituted arylene group, and R6 is a hydrogen atom, a substituted or unsubstituted arylene group, and R6 is a hydrogen atom, a substituted or unsubstituted arylene group, and Represents a substituted alkyl group or a substituted or unsubstituted aryl group.

Specific examples of such compounds are described in detail on pages 3 to 4 of JP-A-58-65440 and pages 3-6 of JP-A-58-198043.

General formula (B) However, R7 is a substituted or unsubstituted aryl group, or a substituted group.

It is an unsubstituted heterocyclic group, and R6 is a hydrogen atom, a direct substitution.

It represents an unsubstituted alkyl group, a substituted or unsubstituted aryl group, and in detail, JP-A-58-134642 and JP-A-58-1.
It is described in the publication No. 66354.

General formula (C) ■ R' However, R' is a substituted or unsubstituted aryl group, and RID
Hydrogen atoms, halogen atoms, substituted and unsubstituted alkyl groups,
Substituted, unsubstituted alkoxy group, substituted.

It is an unsubstituted amino group or a hydroxy group, and R11 represents a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. Synthesis methods and examples of these compounds are given in Japanese Patent Publication No. 57-
148750, which can be incorporated into the present invention.

Other preferred carrier transport materials include JP-A No. 5
No. 7-67940, No. 59-15252, No. 57-1
The hydrazone compounds described in No. 01844 can be mentioned.

In the present invention, an antioxidant is used as an essential constituent material of the photosensitive layer. By containing this antioxidant in the photosensitive layer, fatigue deterioration of the photosensitive layer is prevented, and as a result, the high gamma type light attenuation characteristics, which exhibit excellent high gamma characteristics, are stabilized even when the photoreceptor is used repeatedly. It is possible to stably form dot-shaped images with high sharpness over many times.

As the antioxidant, any of the known antioxidants used in conventional electrophotographic photoreceptors can be used, but the following hindered phenols are particularly preferred.

: Hindered phenol dibutylhydroxytoluene bis(6-L-butyl-4-methylphenol), 4.
4'-Butyldenbis(6-t-butyl-3-methylphenol), 4,4'-thiobis(6-t-butyl-3-methylphenol)
-methylphenol), 2,2'-thiodiethylenebis[3-(3.5-di-t-butyl-4.hydroxyphenol)globione)], 1,6-hexanediolbis[3-(3,5 -di-butyl-4-hydroxyphenyl)propionate], σ-tocopherol, β-tocopherol, pentaerythrityl-tetrakis[3-(3,5-di-L-butyl-4-hydroxyphenyl)propionate], 2.2. 4-trimethyl-
Pintate phenols such as 6-hydroxy 7-t-butylchroman, dibutylhydroxyanisole, pentaerythrityl-tetrakis [3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], etc. , [-'O Active species such as ozone and NO8 generated by repeated processes are efficiently absorbed to effectively prevent fatigue deterioration of the photosensitive layer.

The content of the antioxidant is preferably 0.01 to 1 OOvt/wt, particularly preferably 0.1 to 50 wt/vt, per 100 wt of the photoconductive organic pigment contained in the photosensitive layer.

Within this range, fatigue deterioration of the photosensitive layer can be effectively prevented without impairing the properties of the photosensitive layer.

Note that if the amount of antioxidant is too small, its function will be insufficient. On the other hand, if it is too large, the insulation resistance of the photosensitive layer decreases and high charging properties cannot be obtained, resulting in loss of high gamma characteristics.
Furthermore, since the surface hardness of the photosensitive layer is reduced, the photosensitive layer is damaged early due to rubbing by a blade or brush during the cleaning process.

Any binder resin can be used to form the photoconductive layer, but it should be a hydrophobic, high dielectric constant, electrically insulating film-forming polymer, and a thermosetting resin. It is preferable that there be.

Thermosetting resins include condensation polymerization type and addition polymerization type.

Condensation polymerization types include phenol resins, urea resins, melamine resins, melamine-7 enol resins, guanamine resins, and silicone resins, and addition polymerization types include unsaturated polyester resins, alkyd resins, diallyl phthalate resins, and epoxy resins. There are resins and polybutadiene resins.

Note that other resins may be used in combination without impairing performance.

Examples include, but are not limited to, the following:

Polycarbonate, methacrylic acid resin, acrylic resin,
polyvinyl chloride, polyvinylidene chloride, polystyrene,
Polyvinyl acetate, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-
Maleic anhydride copolymer, silicone-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, poly-N-vinylcarbazole, polyvinyl butyral These binder resins can be used alone or as a mixture of two or more.

The photoconductive layer may contain one or more electron-accepting substances for the purpose of improving sensitivity, reducing residual potential fatigue during repeated use, and the like.

The amount of electron-accepting substance added is carrier-generating substance:electron-accepting substance-too: (0.01 to 200) by weight.
, preferably 100:(0.1-100).

Specific examples of electron-accepting substances are disclosed in JP-A-63-168656.
It is stated in the number etc.

Further, the photoreceptor of the present invention may also contain an ultraviolet absorber or the like for the purpose of protecting the photosensitive layer, if necessary, or a dye for color sensitivity correction.

In the photoreceptor of the present invention, a photoconductive layer and, if necessary, auxiliary layers such as a protective layer, an intermediate layer, a barrier layer, and an adhesive layer may be laminated on the support.

Regarding the photoconductive layer, the following method is appropriately used.

l) A method of applying a solution in which a photoconductive substance is dissolved in a suitable solvent, or a solution in which a binder resin is mixed and dissolved, if necessary.

2) The photoconductive substance is made into fine particles (preferably particle size of 5 μm or less, more preferably 1 μm or less) in a dispersion medium using a ball mill, homomixer, etc., and a binder resin is added as necessary to mix and disperse the resulting dispersion, and the resulting dispersion is applied. Method.

Examples of the solvent or dispersion medium used for forming the photoconductive layer include butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N,N-dimethylformamide,
Acetone, methyl ethyl ketone, cyclohexanone, benzene, toluene, xylene, chloroform, 1.2-
Dichloroethane, 1,2-dichloropropane, 1,1.
2-Trichloroethane, 1.1. i-trichloroethane,
Trichlorethylene, tetrachloroethane, dichloromethane, tetrahydrofuran, dioxane, methanol,
Examples include ethanol, impropanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl cellosolve, methyl imbutyl ketone, and the like.

The conductive support used for the photoreceptor may be a metal plate containing an alloy, a metal drum, or a conductive polymer, coated with a thin layer of metal such as aluminum, palladium, or gold containing a conductive compound or alloy such as indium oxide. Examples include paper, plastic film, etc., made conductive by vapor deposition or lamination.

As an intermediate layer such as an adhesive layer or a barrier layer, in addition to the polymer used as the binder resin, an organic polymer material such as polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, or aluminum oxide is used.

Next, the specific structure of the photoreceptor of the present invention will be described.

FIG. 4 is a sectional view of a photoreceptor according to an embodiment of the present invention.

In FIG. 4(a), l is a support, 2 is a photoconductive layer (P
CL).

The layer structure of the photoreceptor of the present invention is not limited to that shown in FIG. 4(a), and various embodiments are possible.

For example, in Fig. 4, 3 in Fig. 4 (b) is Ti of CGM.
This is a PCL that is a hybrid of 0Pc and CTM.

Auxiliary layers may be utilized in the present invention, and in FIG. 4, a protective layer 5, a barrier layer (or adhesive layer) 4, an intermediate layer 6
An example of an embodiment is shown below.

In the PCL, the weight ratio of CGM and binder is preferably 5:100 to 50:100.

If the content of CGM is less than this, the photosensitivity will be low and the residual potential will increase, and if it is more than this, dark decay and acceptance potential will decrease.

In FIG. 4, it is preferable that the film layer of PCL2 has a thickness of 5 to 50 μl, more preferably 5 to 30 μl.

Further, in PCL3, CTM is regulated to 0 to 30 vL/wt per 100 binder resin in PCL.

FIG. 5 shows an example of an image forming apparatus using the photoreceptor 11 of the present invention. Here, 20 is a charging electrode, 21 is a long-wave light source, 22 is a short-wave (visible light) light source, 23 is a developing device, 25 is a transfer electrode, 26 is a separation electrode, 27 is a cleaning blade, and 28 is a static elimination lamp. It is.

In addition, light sources that can be used for light *21 and 22 include white light, halogen lamp light, tungsten light, fluorescent lamp light, laser light (semiconductor laser, Ha-Ne laser), LED, and the like.

The developing device 23 may use either a normal forward development method or a reversal development method. The static elimination lamp 28 is effective during both forward development and reverse development.

When forming an image, first of all, when using a white light source,
The photoreceptor is charged at 20 t; the photoreceptor is imagewise exposed at 22 t;
It is developed with This is transferred onto a transfer paper 24 using 25 transfer electrodes, and the transfer paper is separated using 26 separation electrodes.

The toner remaining on the photoreceptor 11 is scraped off at 27 for cleaning.

On the other hand, when a laser light source is used, the photoreceptor charged at 20 is imagewise exposed at 21 and developed at 23. This is transferred onto transfer paper 24 using 25 transfer electrodes, and 2
The transfer paper is separated by the separation electrode 6. 27 toners left
is cleaned with.

In a recording apparatus that uses a drum-shaped photoreceptor like this recording apparatus, image exposure using a laser light source is preferably performed using a laser beam scanner as shown in FIG.

The operation of the laser beam scanner shown in FIG. 6 will now be described.

A laser beam generated by a semiconductor laser 41 is swung left and right within a predetermined amplitude angle by a polygon mirror 43 rotated by a drive motor 42, passes through an f-theta lens 44, and has an optical path bent by a reflecting mirror 45 to reach a photoreceptor. 23 and scans over a line 46.

47 is an index sensor for detecting the start of beam scanning, and 48 and 49 are cylindrical lenses for correcting the inclination angle. Reflecting mirrors 50a, 56b, and 50c form a beam scanning optical path and a beam detection optical path.

When scanning is started, the beam is detected by the index sensor 47, and modulation of the beam by a signal is started by a modulation section (not shown). The modulated beam scans over a photoreceptor that has been uniformly charged in advance by a charger 20.

A latent image is formed on the drum surface by main scanning by the laser beam 51 and sub-scanning by the rotation of the photoreceptor.

Further, in a recording apparatus in which the photoreceptor is in a flat state like a belt, the image exposure can be set to 7 lashes.

〔Example〕

Examples 1 to 9 of the present invention are listed below, and Comparative Examples (1) to (
5), the embodiments of the present invention are not limited to the following examples.

First, prior to illustrating embodiments, synthesis of Y-type titanyl phthalocyanine used for detailed explanation of the present invention will be explained.

(Synthesis of TiOPc) Synthesis Example 1 Mix 29.2 g of 1.3-diiminoisoindolizine and 200 mQ of sulfolane, and add titanium tetraisopropoxide; 17. og was added thereto, and the mixture was reacted at 140°0 for 2 hours under a nitrogen atmosphere. After cooling, the precipitate was collected by filtration, washed with chloroform, washed with 2% hydrochloric acid, and washed with water.
After washing with methanol and drying, 25.5g (88,
5%) of titanyl phthalocyanine was obtained.

The product was dissolved in 20 times the amount of concentrated sulfuric acid, poured into 100 times the amount of water, precipitated and collected by filtration, and the wet cake total 1.2
- Heating with dichloroethane at 50°C for 10 hours as shown in Figure 1 (
Y type T 1OPc with the X-ray diffraction spectrum shown in a)
And so. In this crystal, the peak intensity at a Bragg angle of 2θ of 9.6° was 102% of that at a Bragg angle of 27.2°.

Let this be Ti0PcY.

Synthesis Example 2 A wet cake obtained by the same treatment as in Synthesis Example 1 was stirred in 1,2-dichloroethane at room temperature for 1 hour to obtain Y-type T 1OPc. In this crystal, the peak intensity at 9.6% of the Bragg angle 2θ was 75% of that at 27.2%.

This is designated as Ti0Pc Y2.

Synthesis Example 3 Phthalodinitrile; 25.6 g and σ-chlornaphthalene; 6.5-
of titanium tetrachloride was added dropwise, and the mixture was reacted at 200 to 220°C for 5 hours. The precipitate was collected by filtration and washed with σ-chlornaphthalene, followed by chloroform washing and then methanol washing.

The mixture was then refluxed in aqueous ammonia to complete hydrolysis, washed with water, washed with methanol, and dried to obtain 21.8 g (75.6%) of titanyl 7-dironanine.

The product was dissolved in 10 times the amount of concentrated sulfuric acid, poured into 100 times the amount of water, precipitated and collected by filtration, and the wet cake was dissolved in 1.2-
The mixture was stirred in dichloroethane at room temperature for 1 hour to obtain Y-type T 1OPc having the X-ray diffraction spectrum shown in FIG. 1(b). The peak intensity of this crystal at a Bragg angle 2θ of 9.6″ was 45% of that at 27.2°.

This is designated as Ti0Pc Y3.

Synthesis Example 4 A wet cake obtained in exactly the same manner as in Synthesis Example 3 was stirred in 0-dichlorobenzene in room a for i hours to obtain Y-type Ti0Pc. This crystal has a Bragg angle of 2θ of 9
．． The peak intensity at 6° was 35% of that at 27.2°. This is designated as Ti0Pc Y4.

The requirements for preparing a photoreceptor sample are as follows.

(Preparation of Photoreceptor) Next, a photoreceptor having a PCL shown in FIG. 4 was prepared using the Y-type titanyl phthalocyanine.

However, the PCL includes a photoreceptor having a CGM simple structure optical layer lacking CTM.

For the substrate, a 0.3 μm subbing layer (UCL) of polyamide resin was provided on an aluminum drum or a sheet of polyethylene terephthalate film on which aluminum was vapor-deposited, and a paint having the following formulation was deep coated.

Example 1: Prescription-1 (vt) Cyclohexanone 100 Polyester resin IO (Alumatex 74
9; Mitsui Toatsu Chemical) Melamine resin
2 (knee pants 20SE-60; manufactured by Mitsui Toatsu Chemical) TiOPcY r
3 Hindered Phenol 5 (IRG
ANOX 1010; manufactured by Ciba Geigi) The above formulation 'JmI
After mixing and dispersing the R material with a sand grinder for 24 hours, the resulting paint was applied and dried at 120°C for 1 hour to achieve a film thickness of 1.
A photoreceptor 1 having a PCL of 5 μm was obtained.

The photoreceptors of Examples and Comparative Examples described below differ only in the paint formulation, and the manufacturing process was exactly the same to obtain Example Photoreceptors 2 to 9 and Comparative Example Photoreceptors (1) to (5). .

Example 2: Formulation-n (wt) cyclohexanone lOO acrylic resin 10 (Almatex 74
9-7, Mitsui Toatsu Chemical) Melamine resin
2 (knee pants 20SE-60) TiOPc Y 2 4IR
GANOX 1010 10 Example 3: Formulation-m (wt) Inglovir Alcohol 100 Fer/-6
111m (Fly-O 7en 10TD-629H;
(manufactured by Dainippon Ink) TiOPc Y s 3
rRGANOX 1010
5 The formulations of Examples 1 to 3 above, Examples 4 to 9 described later, and Comparative Examples (1) to (5) are listed together on the back page 1.

In addition, the numerical values in the table are based on the weight based on the above prescription * 2 Comparative example (4) uses 1,2-dichloroethane as the dispersion medium of prescription -■, and acrylic resin (Dianaru BR80) as the binder.
; made by Mitsubishi Rayon).

*j was type CuP c (manufactured by Toyo Ink Mfg. Co., Ltd.) The characteristics of the photoreceptor sample obtained above were evaluated, and the results are shown in Table 2.
It was listed on.

(1) Light attenuation characteristics Electrostatic charging test device E P A-8100 (manufactured by Kawaguchi Electric Co., Ltd.) was used to measure the unexposed potential vH at 90% and 50% of the
Energy required to attenuate to (μJ/cm2)
Absolute value of difference IEI. -E. 1 and R-E,. /(E,
. -E. ) was sought.

(2) Repeated durability: 1. %te, initial V H (
-V 14') (!: V after printing 100 times)l(
= V)lIl) difference V, 4-VH1'' absolute value 1ΔH
R (·R101) after printing 1 and 100 times was determined.

(3) Resolving power The laser printer LP3010 (
A modified machine (manufactured by Konica Corp.) equipped with an LD light source AE and a reversal developing mechanism was used. As an optical system, 240, 300, 4
00 and 600 d/i (dot par 1n
ch), following JIS Z4916, each of the 5, 3, 6, 8, and 12 vertical lines as a blade was cut by λ from the signal generator, and the reverse development was performed. As is clear from the above, the photoreceptor of the present invention has excellent sensitivity to laser light and has a high γ.
Shows high resolution. Furthermore, it has stable potential characteristics even after repeated use, and provides clear images.

Because of this, it exhibits high resolution. Furthermore, it has stable potential characteristics even after repeated use, and provides clear images.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an outline of the optical attenuation curve of the photoreceptor of the present invention, FIG. 2 is an X-ray diffraction spectrum diagram of Ti0Pc according to the present invention, FIG. 3 is a spectral absorption spectrum diagram of T1OPc, and FIG.
The figure is a sectional view of an embodiment of the photoreceptor of the present invention. FIG. 5 is a schematic diagram of an example of an image forming apparatus using the photoreceptor of the present invention, and FIG. 6 is an explanatory diagram of the operation of a laser beam scanner.

Claims (3)

[Claims] (1) In an electrophotographic photoreceptor in which a photosensitive layer containing a carrier-generating substance, a carrier-transporting substance, and a binder resin is provided on a substrate, the carrier-generating substance has an X-ray diffraction spectrum for Cu-Kα rays (wavelength 1.541 Å). It is a titanyl phthalocyanine having strong peaks at Black's angle 2θ of 9.6° and 27.2°, and the content of the carrier transport material is 0 to 30wt/100% of the binder resin.
An electrophotographic photoreceptor characterized by being wt and containing an antioxidant. (2) The electrophotographic photoreceptor according to claim 1, wherein the peak intensity of the titanyl phthalocyanine at a Bragg angle 2θ of 9.6° is 40% or more of the peak intensity at 27.2°. (3) Claim 1 or 2, wherein the antioxidant has a hindered phenol structural unit in its molecular structure.
The electrophotographic photoreceptor described in .