JPH0311358A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve an electrostatic charge characteristic, sensitivity characteristic and repetitive characteristic by using specific titanyl phthalocyanine to form the photosensitive body. CONSTITUTION:A photosensitive layer 4 is formed by successively laminating a carrier generating layer 2 and a carrier transfer layer 3 on a conductive base 1. The titanyl phthalocyanine having the crystal type with which the X-ray diffraction spectra to Cu-Kalpha rays exhibit peaks at 9.3 deg.+ or -0.2 deg., 10.6 deg.+ or -0.2 deg., 13.2 deg.+ or -0.2 deg., 15.1 deg.+ or -0.2 deg., 20.8 deg.+ or -0.2 deg., 23.3 deg.+ or -0.2 deg., 26.3 deg.+ or -0.2 deg. of Bragg angle 2theta and contains 0.2wt.% chlorine is incorporated as a carrier generating material into the photosensitive layer. The electrophotographic photosensitive body having the high sensitivity, small residual potential and stable potential characteristics is obtd. in this way.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electrophotographic photoreceptor, which can be effectively used in printers, copiers, etc., and has high sensitivity to semiconductor laser light and LEDs. This invention relates to an electrophotographic photoreceptor exhibiting the following characteristics.

[Prior art]

Electrophotographic photoreceptors have traditionally been made of selenium, zinc oxide,
Inorganic photoreceptors with a photosensitive layer mainly composed of an inorganic photoconductive substance such as cadmium sulfide have been widely used. Cadmium sulfide has poor moisture resistance and durability, and zinc oxide also has poor durability.In recent years, organic photoconductive materials with various advantages have been widely used in electronic applications. It has come to be used in photographic photoreceptors. Among them, phthalocyanine compounds have high photoelectric conversion quantum efficiency and exhibit high spectral sensitivity up to the near-infrared region, so they are attracting attention as a material for electrophotographic photoreceptors that are particularly suitable for semiconductor laser light sources.

For such purposes, electrophotographic photoreceptors using copper phthalocyanine, metal-free phthalocyanine, chlorindium 7-thalocyanine, chlorgallium phthalocyanine, etc. have been reported, but titanyl phthalocyanine has attracted particular attention in recent years. For example, JP-A-61-2392
No. 48, No. 62-670943, No. 62-27227
There have been many technical disclosures of electrophotographic photoreceptors using titanyl phthalocyanine, such as No. 2 and No. 63-116158.

Generally, phthalocyanine compounds are produced by reacting metal compounds with phthalodinitrile, 1,3-diiminoisoindoline, etc., but in the production of titanyl phthalocyanine for electrophotographic photoreceptors, reactivity is Titanium tetrachloride has been used as a raw material. For example, in the production of vanadyl phthalocyanine, which has a structure similar to titanyl phthalocyanine, vanadyl chloride and vanadyl acetylacetonate can be used as raw materials, but in the production of titanyl phthalocyanine, using titanyl acetylacetonate as a raw material increases the yield. is significantly reduced and the purity is also reduced. Therefore, methods for producing titanyl 7-lycyanine for electrophotographic photoreceptors include the above-mentioned Japanese Patent Application Laid-Open Nos. 61-239248, 62-670943,
In addition to No. 62-272272 and No. 63-116158, JP-A-61-171771 and No. 61-1090
No. 56, No. 59-166959, No. 62-25686
No. 8, No. 62-256866, No. 62-256867
No. 63-80263, No. 62-286059,
No. 63366, No. 63-37163, No. 62-13
No. 4651, but in all of these cases, a method using titanium tetrachloride is used.

[Problem that the invention seeks to solve]

When titanium chloride as mentioned above is used as a raw material, 7
This is accompanied by a chlorine reaction of the lysyanine nucleus.

Furthermore, the conventional production method requires high temperature conditions of 180° C. or higher, which is a cause of promoting side reactions of chlorination. For this reason, conventional titanyl 70-cyanine inevitably contains a considerable amount of chlorinated titanyl 70-cyanine, and the chlorinated titanyl phthalocyanine that has been mixed in is physically separated from unsubstituted titanyl phthalocyanine.
Since they have similar chemical properties, they are almost impossible to remove even by recrystallization or sublimation purification, and the titanyl phthalocyanine conventionally used in electrophotographic photoreceptors contained chlorine compounds. For example, the actual measured values of chlorine content in the production example of titanyl 7-cyanine disclosed in the above-mentioned publication are listed in Table 1. .

In this way, in the conventional titanyl 7-lycyanine, Q
, the inclusion of chlorine of about 4 wt% was unavoidable. The value of 0.4vt% as a chlorine atom is 7.9wt when converted to the -chlorinated titanyl phthalocyanine concentration.
% (6.6 mol%), which is a very high value as an impurity concentration.

On the other hand, the electrophotographic properties of phthalocyanine compounds vary significantly depending on their crystalline state, and it is known that even titanyl phthalocyanine has excellent properties when it has a specific crystalline form.

In electrophotographic materials with such structure-sensitive properties, the presence of impurities introduces structural defect sites, which impair the excellent electrophotographic properties of a specific crystal type. It is.

Regarding this point, we conducted intensive studies to obtain highly pure titanyl phthalocyanine, and as a result, we succeeded in applying a manufacturing method that does not involve a chlorination reaction, and the resulting titanyl with low chlorine content. By forming phthalocyanine into a specific crystal structure, it was possible to create an excellent electrophotographic photoreceptor.

[Purpose of the invention]

The purpose of the present invention is to achieve high sensitivity and low residual potential.
An object of the present invention is to provide an excellent electrophotographic photoreceptor with stable potential characteristics.

Another object of the present invention is to provide an electrophotographic photoreceptor with particularly excellent potential holding ability and stable charging potential.

[Structure and effects of the invention]

The above object of the present invention is that the X-ray diffraction spectrum for Cu-Ka line is 9.36±0.26.1 at Bragg angle 2θ.
0.6°±0.2°, 13.2°±0.2°, 15.1
゜±0.2゜, 20.8゜±0.2゜, 23.3゜±0
．． Contains titanyl phthalocyanine in the photosensitive layer, which has a crystal form showing peaks at 2°, 26.3° ± 0.2', and has a chlorine content of Q, 2 wt% or less, preferably 0.1 wt% or less. This can be achieved by letting

The X-ray diffraction spectrum is measured under the following conditions, and the peak is an acute-angled protrusion that is clearly different from noise.

X-ray tube Cu voltage 40. OKV current
100 mA
Starting angle 6. Odeg.

Stop angle: 35-Odeg.

Step angle 0.02 deg.

Measurement time 0.50 sec.

Chlorine content can also be determined by ordinary elemental analysis measurements, but Mitsubishi Chemical's chlorine/sulfur analyzer rTSX-IOJ
It can also be determined by elemental analysis using

In the present invention, the most desirable chlorine content is one below the detection limit in these measurement methods.

The titanyl phthalocyanine of the present invention can be produced with high purity without chlorination by using a titanium compound represented by the following general formula CI). X3, X is -OR,, -5R2
, -0SOzRs1 -p-0R4.

OR.

Here, R1 to R5 represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an aryl group, an aryloyl group, or a heterocyclic group, and these groups may have any substituent. Moreover, X I"" X 4 may be combined in any combination to form a ring.

Y represents a ligand, and n represents 0%1,2. Among these, those in which X, -X, is -OR can be cited as particularly desirable in terms of reactivity, ease of handling, price, etc.

Although various reaction formats are possible as a production method, a method represented by the following reaction formula is typically used.

In the formula, R1 to R1 represent a hydrogen atom or a substituent.

In such a production method according to the present invention, there is no attack by active chlorine, so chlorination of the phthalocyanine nucleus can be completely avoided. In addition, compared to the conventional method using titanium tetrachloride, it has higher reactivity and allows the reaction to proceed in a milder environment, which is not only advantageous for manufacturing conditions, but also prevents side reactions and minimizes impurities. It is something that can be suppressed.

Specific examples of titanium compounds useful in this reaction are shown below.

(1) (CaH*0)aTi (2) (i CJaO), Ti(3) C
c, Hso), ri (4) (t −c*n, o)4T=(5)
(CIaHsyO)aTi(6') (CIH70
)4Ti (7) (i CzHyO)zTi(CHsCO
CHCOC[(x)2(8) (HOCOCHO)
xTi(OH)xCH.

(10) (CJI yO)4Ti [P(OC
sHy)*] xH CH3 Various solvents can be used for the reaction. For example, dioxane, cyclohexane, sulfolane,
Typical examples include aliphatic solvents such as dimethyl sulfoxide, dimethylformamide, dimethylacetamide, and methylpentanone, and aromatic solvents such as chlorobenzene, dichlorobenzene, bromobenzene, nitrobenzene, chlornaphthalene, tetralin, pyridine, and quinoline. However, in order to obtain a highly pure product, it is desirable to have a certain degree of solubility in titanyl phthalocyanine.

The reaction temperature varies depending on the type of titanium coupling agent, but it can be carried out at about 10G-180'o. In this respect as well, the conventional reaction requires a high temperature of 180 to 240'C, whereas this method is advantageous from the viewpoint of preventing side reactions.

The highly purified titanyl phthalocyanine obtained in this way can be treated with an appropriate solvent to obtain the desired crystal form, but the equipment used for the treatment is a homomixer, a visor, An agitator, ball mill, sand mill, attritor, etc. can be used.

In the electrophotographic photoreceptor of the present invention, the above-mentioned titanyl-7-lycyanine is used as a carrier-generating substance, but other carrier-generating substances may also be used in combination. Examples of such carrier-generating substances include titanyl-7-polycyanine which differs in crystal form from that of the present invention, other phthalocyanine pigments, azo pigments, anthraquinone pigments, perylene pigments, polycyclic quinone pigments, squareium pigments, and the like.

Various carrier transport substances can be used in the photoreceptor of the present invention, but representative examples include nitrogen-containing heterocyclic nuclei represented by oxazole, oxadiazole, titanol, thiadiazole, imidazole, etc. Compounds having such condensed ring nuclei, polyarylalkane compounds, pyrazoline compounds, hydrazone compounds, triarylamine compounds, styryl compounds, styryltriphenylamine compounds, β-phenylstyryltriphenylamine compounds, Examples include butadiene compounds, hexatriene compounds, carbazole compounds, and fused polycyclic compounds. Specific examples of these carrier transport substances include, for example, Japanese Patent Application Laid-Open No. 61-107
Examples of the carrier transport substances described in No. 356 can be mentioned, and the structures of particularly typical ones are shown below.

-1 -2 -6- -7- -8 -5 -9 T-10 T-14 -11 -15 -13 -17 C,H.

-18 -19 Various configurations of photoreceptors are known. Although the photoreceptor of the present invention can take any of these forms, it is preferably a multilayer photoreceptor or a dispersed functionally separated photoreceptor.

In this case, the configuration is usually as shown in 0rXJ from FIG. The layer structure shown in FIG. 1 is such that a carrier generation layer 2 is formed on a conductive support l, and a carrier transport layer 3 is laminated thereon to form a photosensitive layer 4. A photosensitive layer 4' is formed by inverting the carrier generation layer 2 and the carrier transport layer 3. In FIG. 3, an intermediate layer 5 is provided between the photosensitive layer 4 and the conductive support l of the layer structure of the first factor, and the fourth
FM has an intermediate layer 5 provided between the photosensitive layer 4' and the conductive support l having the layer structure shown in FIG. The layer structure shown in FIG. 5 forms a photosensitive layer 4'' containing a carrier-generating substance 6 and a carrier-transporting substance 7, and FIG. An intermediate layer 5 is provided therein.

In the configurations shown in FIGS. 1 to 6, a protective layer can be further provided on the outermost layer.

In forming the photosensitive layer, it is effective to apply a solution in which a carrier-generating substance or a carrier-transporting substance is dissolved alone or together with a binder or an additive. However, since the solubility of the carrier-generating substance is generally low, in such cases, a solution in which the carrier-generating substance is dispersed into fine particles in an appropriate dispersion medium using a dispersion device such as an ultrasonic dispersion machine, a ball mill, a sand mill, or a homomixer is used. This method is effective. In this case, the binder and additives are usually added to the dispersion.

A wide variety of solvents or dispersion media can be used to form the photosensitive layer. For example, butylamine, ethylenediamine, N,N-dimethylformamide, acetone, methyl ethyl ketone, cyclohexanone,
Examples include tetrahydrofuran, dioxane, ethyl acetate, butyl acetate, methyl cellosolve, ethyl cellosolve, ethylene glycol dimethyl ether, toluene, xylene, acetophenone, chloroform, dichloromethane, dichloroethane, trichloroethane, methanol, ethanol, propatool, butanol, and the like.

When a binder is used to form a carrier generation layer or a carrier transport layer, any binder can be selected as the binder, but a hydrophobic polymer having film-forming ability is particularly desirable.

Examples of such polymers include, but are not limited to, the following:

Polycarbonate, polycarbonate Z resin, acrylic resin, methacrylic resin, polyvinyl chloride, polyvinylidene chloride, polystyrene, styrene-butadiene copolymer, polyvinyl acetate, polyvinyl formal, polyvinyl butyral, polyvinyl acetal, polyvinyl carbazole, styrene-alkyd resin, Silicone resin,
Silicone-alkyd resin, polyester, phenolic resin, polyurethane, epoxy resin, vinylidene chloride-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer.

The ratio of carrier generating substance to binder is 10 to 60
It is preferably 0 wt%, more preferably 50 to 400 vt%. The ratio of carrier transport substance to binder is lO
It is desirable to set it to 500vt%. The thickness of the carrier generation layer is 0.01 to 20μ■, and more preferably 0.0μ■.
5 to 5 μm is preferable. The thickness of the carrier transport layer is l-1
00 μm, more preferably 5 to 30 μm.

The photosensitive layer may contain an electron-accepting substance for the purpose of improving sensitivity, reducing residual potential, or reducing fatigue during repeated use. Examples of such electron-accepting substances include succinic anhydride, maleic anhydride, dibromo succinic anhydride, phthalic anhydride, tetrachlorophthalic anhydride, tetrabromo-7talic anhydride, 3-nitro-7-thalic anhydride, and 4-nitro-7-thalic anhydride. Phthalic anhydride, pyromellitic anhydride, mellitic anhydride, tetracyanoethylene, tetracyanoquinodimethane, 0-dinitrobenzene, Peng-dinitrobenzene, 1.3.5-) dinitrobenzene, p-nitrobenzonitrile, Vicri chloride, quinone chlorimide, chloranil, chloranil, dichlordicyano-p-benzoquinone, anthraquinone, dinitroanthraquinone, Fy fluorenylidenemalonodinitrile, polynitro-
9-fluorenylidenemalonodinitrile, picric acid,
0-nitrobenzoic acid, p-nitrobenzoic acid, 3,5-dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3,5-dinitrosalicylic acid, phthalic acid,
Examples include mellitic acid and other compounds with high electron affinity. The addition ratio of the electron-accepting substance is 0.01 to 200vt/per 100% of the weight of the carrier-generating substance.
vt is desirable, and more preferably 0.1 to 100 vt/wt.

Further, the photosensitive layer may contain deterioration inhibitors such as antioxidants and light stabilizers for the purpose of improving storage stability, durability, and resistance to environmental dependence. Compounds used for such purposes include, for example, chromanol derivatives such as tocolo-7erol, etherified or esterified compounds of [so], polyarylalkane compounds, hydroquinone derivatives and their mono- and di-etherified compounds, benzophenone derivatives, and benzophenone derivatives. Triazole derivatives, thioether compounds, phosphonic acid esters, phosphorous acid esters, phenylenediamine derivatives, phenol compounds, hindered phenol compounds, linear amine compounds, cyclic amine compounds, hindered amine compounds, and the like are effective. As a specific example of a compound that is particularly effective for
OX l0IOJ, rlRGANOX565J (manufactured by Ciba Geigy), "Sumilizer BHTJ.

Hindered phenol compounds such as Sumilizer MDPJ (manufactured by Sumitomo Chemical Co., Ltd.), Sanol LS-2626
J.

Examples include hindered amine compounds such as Sanol LS-622LDJ (manufactured by Sankyo Co., Ltd.).

As the binder used for the intermediate layer, protective layer, etc., those listed above for the carrier generation layer and carrier transport layer can be used, but in addition, polyamide resin, ethylene-vinyl acetate copolymer, ethylene-acetic acid Ethylene resins such as vinyl-maleic anhydride copolymers and ethylene-vinyl acetate-methacrylic acid copolymers, polyvinyl alcohol, cellulose derivatives, and the like are effective. Further, a hardening type binder using ripe hardening or chemical hardening such as melamine, epoxy, incyanate, etc. can be used.

As the conductive support, a metal plate or a metal drum is used, or a thin layer of a conductive polymer, a conductive compound such as indium oxide, or a metal such as aluminum or palladium is coated on paper by means such as coating, vapor deposition, or lamination. It is possible to use a substrate provided on a substrate such as or a plastic film.

The photoreceptor of the present invention has the above-described structure, and as is clear from the following examples, it has excellent charging characteristics, sensitivity characteristics, and repeatability characteristics.

〔Example〕

Next, specific examples of the present invention will be shown.

Synthesis Example 1 1.3-diiminoisoindoline; 29.2g and sulfolane; 200! Mix IQ and titanium triisopropoxide; 17. Add Og and 1 ml under nitrogen atmosphere.
The reaction was carried out at 40°C for 2 hours. After cooling, the precipitate was collected by filtration, washed with chloroform, washed with a 2% aqueous hydrochloric acid solution, washed with water, washed with methanol, and dried.
%) of titanyl phthalocyanine was obtained. Chlorine was below the detection limit in elemental analysis.

The product was dissolved in 20 times the volume of concentrated sulfuric acid, poured into 100 times the volume of water, precipitated, collected by filtration, dried, and treated with 0-dichlorobenzene to obtain the X-ray diffraction spectrum shown in Figure 7. It was made into a crystalline type.

Synthesis Example 2 1,3-diiminoisoindoline; 29.2g and α-
Mix chlornaphthalene; 2001112, add titanium tetrabutoxide; 20.4 g, and heat at 140-150'C under nitrogen atmosphere! Heat for 2 hours, then 1
The reaction was carried out at 80°C for 3 hours. After cooling, the precipitate was collected by filtration, washed with sulfolane, then washed with chloroform, further washed with a 2% aqueous hydrochloric acid solution, washed with water, and finally washed with methanol. After drying, 26.2 g (91.0% ) titanyl phthalocyanine was obtained. The value of chlorine content in elemental analysis was 0.0θwt%.

Synthesis Example 3 Titanyl 7-a cyanine obtained in Synthesis Example 1; 1.2 g and titanyl phthalocyanine obtained in Comparative Synthesis Example 1 described below;
0.8 g was dissolved in 40 g of concentrated sulfuric acid, poured into 400 g of water, precipitated, collected by filtration, dried and treated with 0-dichlorobenzene to obtain the titanyl phthalocyanine of the present invention with a chlorine content of 0.19 ft%. Ta.

Comparative Synthesis Example (1) In a mixture of 25.6 g of phthalodinitrile and 150 mQ of σ-chlornaphthalene under a nitrogen stream (i, 5 m
Titanium tetrachloride (Q) was added dropwise and reacted at a temperature of 200 to 220°C for 5 hours. The precipitate was collected by filtration, washed with σ-chlornaphthalene, then with chloroform, and then with methanol. Next, after refluxing in ammonia water to complete hydrolysis, washing with water, washing with methanol, and drying, titanyl phthalocyanine; 21.8 g (75.6%
) was obtained. The chlorine content according to elemental analysis is 0°4fiw
It was t%.

The product was dissolved in 10 times the amount of concentrated sulfuric acid, poured into 100 times the amount of water, precipitated, collected by filtration, dried, and treated with N-methylpyrrolidone to form crystals with the X-ray diffraction spectrum shown in Figure 9. It was made into a mold.

Comparative Synthesis Example (2) Titanyl 7-lycyanine obtained in Synthesis Example 1; 0.6 g and titanyl 7-lycyanine obtained in Comparative Synthesis Example [I]; 1
．． 4 g was dissolved in 40 g of concentrated sulfuric acid, poured into 400 g of water, precipitated, collected by filtration, dried, and treated with N-methylpyrrolidone to obtain a crystal form having an X-ray diffraction spectrum shown in Fig. 1θ. In this case, the chlorine content according to elemental analysis is 0.3
It was 1 ft%.

Comparative Synthesis Example (3) Phthalodinitrile; 25.6g replaced with 7-thalodinitrile; 24.7g and 4-chloro-7thalodinitrile;
Comparative titanyl 7-lycyanine having a chlorine content of 1.14 vt% was obtained in the same manner as in Comparative Synthesis Example 1, except that 1.0 g of the mixture was used.

Example 1 1 part of titanyl phthalocyanine having the X-ray diffraction pattern shown in FIG. 7 obtained in Synthesis Example 1, 0.5 part of polyvinyl butyral "S-LEC BLSJ (manufactured by Okisui Kagaku Co., Ltd.)" as a binder resin, and 0.5 part of polyvinyl butyral as a binder resin. Proper tool: 100 parts was dispersed using a sand mill, and this was coated on a polyester base coated with aluminum using a wire bar to form a carrier generation layer with a film thickness of 0.2μ. T-1: 1 part, polycarbonate resin "Nipiron Z200J (manufactured by Mitsubishi Gas Chemical Co., Ltd.); 1-3 parts, and as an additive, "Sanol LS-2626J (manufactured by Sankisha) 0.03 part, a trace amount of silicone oil. A solution of rKF-54J (manufactured by Shin-Etsu Chemical Co., Ltd.) dissolved in 10 parts of
A carrier transport layer was formed.

The photoreceptor thus obtained is referred to as sample 1.

Example 2 Titanyl phthalocyanine in Figure 8 obtained in Synthesis Example 2; eye L
Silicone modified resin KR-52 as binder resin
1 part of 40J (manufactured by Shin-Etsu Chemical Co., Ltd.) and 100 parts of methyl ethyl ketone as a dispersion medium were dispersed using an ultrasonic dispersion device. On the other hand, polyamide resin rCM8000J (manufactured by Toshisha Co., Ltd.) was used on a polyester base coated with aluminum.
An intermediate layer having a thickness of 0.2 .mu.m was provided, and the dispersion obtained above was applied thereon by dip coating to form a carrier generation layer having a thickness of 0.3 .mu.m. Next, 1 part of carrier transport substance T-5 and polycarbonate resin [Panlite K-1300J (manufactured by Ondai Kasei Co., Ltd.; 1.3 parts and a trace amount of silicone oil rKF-54X manufactured by Shin-Etsu Chemical Co., Ltd.] were mixed with 1.2-dichloroethane. 10 parts of the solution was applied by dip coating, and after drying, a carrier transport layer with a thickness of 20 μl was formed.

The photoreceptor thus obtained is designated as Sample 2.

Example 3 A photoreceptor was produced in the same manner as in Example 2, except that the titanyl phthalocyanine in FIG. 7 was replaced with the titanyl phthalocyanine obtained in Synthesis Example 3. This is called sample 3.

Comparative Example (1) Example 1 except that the titanyl phthalocyanine shown in FIG. 7 in Example 2 was replaced with the comparative titanyl phthalocyanine having the X-ray diffraction pattern shown in FIG. 9 obtained in Comparative Synthesis Example [I]. A comparative photoreceptor was obtained in the same manner. This will be referred to as comparative sample (1).

Comparative Example (2) The same procedure as Example 2 was carried out except that the titanyl phthalocyanine shown in Fig. 7 in Example 2 was replaced with the comparative titanyl phthalocyanine having the X-ray diffraction pattern shown in Fig. 10 obtained in Comparative Synthesis Example (2). A comparative photoreceptor was obtained in the same manner. This will be referred to as comparative sample (2).

Comparative Example (3) A comparative photoreceptor was prepared in the same manner as in Example 2, except that the titanyl phthalocyanine shown in FIG. 7 in Example 2 was replaced with the comparative titanyl phthalocyanine obtained in Comparative Synthesis Example (3). Obtained. This will be referred to as comparative sample (3).

(Evaluation 1) The sample obtained as described above was evaluated as follows using a paper analyzer EPA-8100 (manufactured by Kawaguchi Electric Co., Ltd.). First, corona charging was performed for 5 seconds under the condition of -80 μA, and the surface potential Va immediately after charging and the surface potential Vi after being left for 5 seconds were determined.
(1ux), and the surface potential was reduced to 1/2.
Exposure amount E17. required to obtain Vi. I asked for Also D-
100(Va-Vi)/Va(%)(7) Formula Yo'
The J tti K decay rate was determined. The results are shown in Table 1.

By reducing the chlorine content, particularly excellent potential holding ability can be obtained.

(Evaluation 2) Evaluation was performed using the obtained sample or a modified printer in which a printer LP-3010 (manufactured by Konica) was equipped with a semiconductor laser light source. The unexposed portion potential VH1 and the exposed portion potential VL were determined, and the amount of decrease ΔVH in VH after 10,000 repetitions was determined. The results are shown in Table 1.

Table 1 3...Carrier transport layer 5...middle class 4.4'

Claims (3)

[Claims] (1) The X-ray diffraction spectrum for Cu-Kα radiation is 9.3°±0.2° and 10.6°±0.
2゜, 13.2゜±0.2゜, 15.1゜±0.2゜,
An electrophotographic photoreceptor comprising titanyl phthalocyanine having a crystalline form having peaks at 20.8°±0.2° and 26.3°±0.2° and having a chlorine content of 0.2% by weight or less. (2) The titanyl phthalocyanine has the following general formula [
2. The electrophotographic photoreceptor according to claim 1, which is manufactured by a method using a titanium compound represented by [I]. General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, X_1, X_2, X_3, and X_4 are -OR_1
, -SR_2, -OSO_2R_3▲There are mathematical formulas, chemical formulas, tables, etc.▼Represents. Here, R_1 to R_5 represent a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, an aracyl group, an acyl group, an aryloyl group, or a heterocyclic group, and these groups may have any substituent. Further, X_1 to X_4 may be combined in any combination to form a ring. Y represents a ligand, and n represents 0, 1, or 2. ] (3) The electrophotographic photoreceptor according to claim 1 or 2, wherein the titanyl phthalocyanine is used as a carrier generating substance.