JPH0310256A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain the excellent photosensitive body which has a high sensitivity and small residual potential and stable potentialcharacteristics by incorporating titanyl phthalocyanine having <=0.2wt.% chloride content in the specific amorphous crystal state. CONSTITUTION:The titanyl phthalocyanine contd. <=0.2wt.% chlorine in the amorphous crystal state with which the X-ray diffraction spectra to Cu-Kalpha-rays exhibits a peak at 6.5 deg.+ or -7.5 Bragg angle 2theta. While the titanyl phthalocyanine is used as a carrier generating material, the combination use of other carrier generating materials is equally satisfactory. The ratio of a carrier generating material to a binder is preferably specified to 10 to 600wt.% and the ratio of a carrier transfer material to the binder is preferably specified to 10 to 500wt.%. The photosensitive body having the excellent electrostatic characteristics, sensitivity characteristics and repetitive 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. The present 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 electrophotography. It has come to be used for photoreceptors. Among them, phthalocyanine compounds have high photoelectric conversion quantum efficiency and exhibit high spectral sensitivity up to the near-infrared region, and have therefore attracted 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 phthalocyanine, 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 are many technical disclosures regarding electrophotographic photoreceptors using titanyl phthalocyanine, such as No. 2 and No. 63-116158.

Generally, phthalocyanine compounds are produced by reacting phthalodinitrile or 1.3-diiminoisoindoline with a metal compound, but in the production of titanyl phthalonanine for electrophotographic photoreceptors, reactive Titanium tetrachloride has been used exclusively as a raw material. For example, in the production of vanadyl 7-thalocyanine, which has a similar structure to titanyl phthalocyanine, vanadyl chloride and vanadyl acetylacetoite can be used as raw materials, but in the production of titanyl phthalocyanine, titanyl acetylaceto The use of nitride as a raw material significantly reduces the yield and also reduces the purity. For this reason, as a method for producing titanyl phthalocyanine for electrophotographic photoreceptors, there are
No. 943, No. 62-272272, No. 63-1161
In addition to No. 58, JP-A-61-171771 and JP-A-61-171771
-109056, 59166959, 62-2
No. 56868, No. 62-256866, No. 62256
No. 867, No. 63-80263, No. 62-28605
No. 9, No. 63366, No. 63-37163, No. 62
In all of these cases, a method using titanium tetrachloride is used.

[Problem to be solved by invention]

When using titanium chloride as the raw material 1 involves a chlorine reaction of the phthalocyanine 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 phthalocyanine 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 value of the chlorine content in the production example of titanyl phthalocyanine disclosed in the above-mentioned publication is listed. In Table 1, (note) M'' = 610 corresponds to monochlorinated titanyl phthalocyanine.

In this way, conventional titanyl phthalocyanine has 3
．． The inclusion of about 4 wt% chlorine was unavoidable. The value of Q as a chlorine atom, 4 wt%, is 7.0 wt% when converted to the concentration of chlorinated titanyl phthalonanine.
(6.6 mol%), which is a very high value as an impurity concentration.

On the other hand, the electrophotographic properties of phthalonanine 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 properties that are structurally sensitive, the presence of impurities introduces structural defect sites that impair the excellent electrophotographic properties of a specific crystal type. It is.

Regarding this point, we conducted intensive studies to obtain high-purity titanyl phthalocyanine, and as a result, we succeeded in applying a manufacturing method that does not involve a chlorination reaction. By forming titanyl phthalonanine 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 having 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-mentioned object of the present invention is to provide an amorphous crystalline state in which the X-ray diffraction spectrum for Cu-Kα rays shows a peak at Bragg angle 2θ of 6.5°±7.5, and the chlorine content is 0. .2wt% or less, preferably 0.1wt
% or less of titanyl phthalonanine in the photosensitive layer.

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 4 (10KV current
100mA
8 Starting angle 6. Odeg.

Stop angle 35. Odeg.

Step angle 0.02 6eg.

Measurement time 0.50 sec.

The chlorine content can also be determined by ordinary elemental analysis measurements, but the chlorine and sulfur analyzer rTSX-10J manufactured by Mitsubishi Chemical Corporation
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 by using a titanium compound represented by the following format [I] and accompanied by chlorination. 3 In the formula, xl, X2, X3, X4 are -OR,, -3R2,
-0SOJi1 Elbow OR, not expressed.

R5 Here, RI-R5 represents 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, X1 to X4 may be combined in any combination to form a ring.

Y represents a ligand, and n represents 0, ■, or 2. Among these, those having X1 to x4 or -OR can be cited as desirable in terms of reactivity, ease of handling, and price.

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 R16 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) (C4t(so)aT+ (2) (i-C3t(to)tTi(3)(C2
H5o)4T1 (4) (+ C+t(to)tT+(5)
(C+8H3yO)4Ti(6) (C3H70
)ITI (7) (i-CJ70)2Ti(CH3COCH
COCH3)2(8:) (HOCOCHO)2Ti(
OH)2OH3 (10) (Call+r, Ti [P(OC3H7
)zl tOH 6 mouth I 1 (12) 1-C3H,OTi [0-P-01 P(OC8H,□)213 Of( 2 (13) 1-C3H,0Ti(OC2H4NHC2
H,NH□)3(14) (C,H1□O)J+[P
(OC+31by)21a■ OH (15) [(CH2=CHCH20CH2), CC
H20E1Tr [P(OC,Hzy)z]z2H50
H 1 (19) + CJ70Ti (OCC+ 7H35
)3 It is possible to use various solvents as the reaction solvent. For example, aliphatic solvents such as dioxane, cyclohexane, sulfolane, dimethyl sulfoxide, dimethylbormamide, dimethylacetamide, methylpentanone, aromatic solvents such as chlorobenzene, dichlorobenzene, bromobenzene, nitrobenzene, chlornaphthalene, tetralin, pyridine, quinoline, etc. Typical examples include solvents, but in order to obtain a highly pure product, it is desirable to have a certain degree of solubility for titanyl phthalocyanine.

The reaction temperature varies depending on the type of titanium coupling agent, but it can be carried out at about 100 to 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. However, in addition to a general stirring device, the equipment used for the treatment is a homomixer, a divider, An agitator, ball mill, sand mill, attritor, etc. can be used.

In the electrophotographic photoreceptor of the present invention, the titanyl-7-thalocyanine described above is used as a carrier-generating substance, but other carrier-generating substances may also be used in combination. Such carrier-generating substances include titanyl phthalocyanine 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 as the carrier transport substance in the photoreceptor of the present invention, but representative examples include nitrogen-containing heterocyclic nuclei represented by oxazole, oxadiazole, titanol, thiadiazole, imidazole, etc., and their condensations. Compounds having a ring nucleus, polyarylalkane compounds, pyrazoline compounds, hydrazone compounds, triarylamine compounds, styryl compounds,
styryltriphenylamine compounds, β-phenylstyryltriphenylamine compounds, butadiene compounds, hexatriene compounds, carbazole compounds,
Examples include fused polycyclic compounds. Specific examples of these carrier transport substances include, for example, Japanese Patent Application Laid-Open No. 61-1073.
The carrier transport substances described in No. 56 can be mentioned, and the structures of particularly typical ones are shown below.

-1 5 6- -6- -7- -8 -5 -9 T-10 T-14 -11 -15 -12 -16 -13 T -1,7 2H6 9 0 T~18 -19 Structure of photoreceptor is known in various forms. Although the photoreceptor of the present invention can take any of these forms, it is preferable to use a laminated type or a dispersed type of functionally separated type photoreceptor.

In this case, the configuration is usually as shown in FIGS. 1 to 6. The layer structure shown in FIG. 1 is such that a carrier generation layer 2 is formed on a conductive support 1, and a carrier transport layer 3 is laminated thereon to form a photosensitive layer 4. A photosensitive layer 4' in which the carrier generation layer 2 and the gear transport layer 3 are reversed.
was formed. 3, an intermediate layer 5 is provided between the photosensitive layer 4 and the conductive support 1 having the layer structure shown in FIG. 1, and FIG. 4 shows the photosensitive layer 4' and the conductive support 1 having the layer structure shown in FIG. An intermediate layer 5 is provided between the two. The layer structure shown in FIG. 5 is a photosensitive layer 4 containing a carrier-generating substance 6 and a carrier-transporting substance 7.
'', and FIG. 6 shows such a photosensitive layer 4.
An intermediate layer 5 is provided between the conductive support l and the conductive support l.

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 carrier-generating substances is generally low, in such cases, a liquid 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 prepared. The coating method is effective. In this case, binders 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,
Tetrahydrofuran, dioxane, ethyl acetate, butyl acetate, methyl cellosolve, ethyl cellosolve, ethylene glycol dimethyl ether, toluene, xylene, acetophenone, chloroform, dichloromethane, dichloroethane, 1-helichloroethane, methanol, ethanol, 70 panol, butanol, etc. I get kicked.

When a binder is used to form the carrier generation layer or the gear 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 resin, 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-hinyl acetate-maleic anhydride copolymer The ratio of carrier generating substance to binder is 10 to 600w
The content is preferably t%, more preferably 50 to 400yt%. The ratio of carrier transport substance to binder is 10-5
It is desirable to set it to 00wt%. The carrier generation layer has a thickness of 0.01 to 20 μm, more preferably 0.05 to 5 μm. The thickness of the carrier transport layer is 1 to 100 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 phthalic anhydride, 3-nitro phthalic anhydride, 4-21. Phthalic anhydride, pyromellitic anhydride, mellitic anhydride, tetracyanoethylene, 1-lacyanoquinodimethane, o-dinitrobenzene, m-dinitrobenzene, 1,3.5-1-dinitrobenzene, p-nitro Benzonitrile, picryl chloride, quinone chlorimide, chloranil, chloranil, dichlorodicyano-
p-benzoquinone, anthraquinone, dinitroanthraquinone, 9-fluorenylidenemalonodinitrile, polynitro-9-fluorenylidenemalonodinitrile, picric acid, 0-nitrobenzoic acid, p-21-mouthbenzoic acid,
3,5-dinitrobenzoic acid, pentafluorobenzoic acid,
Examples include 5-nitrosalicylic acid, 3,5 dinitrosalicylic acid, phthalic acid, mellitic acid, and other compounds with high electron affinity. The addition ratio of the electron-accepting substance is 0.01-20 per 100 weight of the carrier-generating substance.
0wt/wt is desirable, and more preferably 0.1 to 100wt/
wt is preferred.

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 tocopherols and their etherified or esterified compounds, polyarylalkane compounds, hydroquinone derivatives and their mono- and dietherized compounds, benzphenone derivatives, benzotriazole derivatives, thioether compounds, phosphonic acid esters, phosphorous acid esters,
Effective are phenylenediamine derivatives, phenol compounds, hindered phenol compounds, linear amine compounds, cyclic amine compounds, and hindered amine compounds. Specific examples of particularly effective compounds include rl[GANOX
l0IOJ, r [GANOX565J (manufactured by Chipa Geigy), [Sumilizer B HT J] Hindered phenol compounds such as Sumilizer MDPJ (manufactured by Hosodai Kagaku Kogyo Co., Ltd.), [Sanol LS-2626J, r Zanol LS-622LDJ (Sankyosha) Examples include hindered amine compounds such as

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 copolymer, ethylene-hinyl acetate-methacrylic acid copolymer, polyhinyl alcohol, cellulose derivatives, etc. are effective. Also, melamine,
A hardened binder using thermosetting or chemical curing such as uboxy, isocyanate, 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 Mix 29.2 g of 1.3-diiminoisoindoline and 200 m+2 of sulfolane, add 17.0 g of titanium triisopropoxide, and heat at 140° under a nitrogen atmosphere.
The reaction was carried out at 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. 25.5 g (88.8%)
of titanyl-7 talocyanine was obtained. Chlorine was below the detection limit in elemental analysis.

The product was dissolved in 20 times the amount of concentrated sulfuric acid, poured into 100 times the amount of water, precipitated, collected by filtration, and dried to obtain a crystal form with the X-ray diffraction spectrum shown in Figure 7.
child .

Synthesis Example 2 29.2 g of 1.3-diiminoisoindoline and 200 mff of α-chlornaphthalene were mixed, 20.4 g of titanium tetrabutoxide was added, and the mixture was heated under a nitrogen atmosphere for 1
The mixture was heated at 40-150°C for 2 hours, and then reacted at 180°C for 3 hours. After cooling, the precipitate was collected by filtration, washed with sulfolane, then washed with chloroform, and further washed with 2%
Wash with aqueous hydrochloric acid solution, wash with water, and finally wash with methanol.
After drying, 26.2 g (91.0%) of titanyl phthalocyanine were obtained. The value of chlorine content in elemental analysis is 0.
It was 0.08 wt%.

The product was dissolved in 20 times the amount of concentrated sulfuric acid, poured into 100 times the amount of water, precipitated, filtered, and dried to give a crystal form with the X-ray diffraction spectrum shown in Figure 8.

Synthesis Example 3 Titanyl phthalocyanine obtained in Synthesis Example 1; 1.2 g and titanyl phthalocyanine obtained in Comparative Synthesis Example 1 described below; 0.
Dissolve 8g in 40g of concentrated sulfuric acid, add 1 in 400g of water,
The chlorine content is 0.19.
wt% titanyl phthalocyanine of the present invention was obtained.

Comparative Synthesis Example (1) Phthalodinitrile; 25.6 g and α-chlornaphthalene.

6.5 m12 of titanium tetrachloride was dropped into the 150 mff mixture under a nitrogen stream,
Allowed time to react. The precipitate was collected by filtration, washed with a-chloronaphthalene, 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 7 talocyanine; 21.8 g (75.6%)
I got it. Chlorine content according to elemental analysis is 0.46wt%
Met.

The product was dissolved in 1 fl volume of concentrated sulfuric acid, poured into 100 times the volume of water, precipitated, collected by filtration, and dried to form a crystal form having the X-ray diffraction spectrum shown in Figure 9.

Comparative Synthesis Example (2) Titanyl phthalocyanine obtained in Synthesis Example 1; 0.6 g and titanyl phthalonanine obtained in Comparative Synthesis Example (1); 1.4
g was dissolved in 40 g of concentrated sulfuric acid, poured into 400 g of water, precipitated, collected by filtration, and dried to obtain a crystal form having the X-ray diffraction spectrum shown in FIG. In this case, the chlorine content according to elemental analysis was 0.31 wt%.

Comparative Synthesis Example (3) 24.7 g of phthalodinitrile i and 4-chlorophthalodinitrile in place of 25.6 g of phthalodinitrile; 1.
In the same manner as Comparative Synthesis Example 1 except that a mixture of Og was used,
Comparative titanyl 7 talocyanine with a chlorine content of 1.14 wt% was obtained.

Example I X-ray diffraction pattern 'y in FIG. 7 obtained in Synthesis Example 1
1 part of titanyl phthalocyanine, 0.5 parts of silicone modified resin rKR-5240J (manufactured by Shin-Etsu Chemical Co., Ltd.) as a binder resin, and 100 parts of Improper Tool as a dispersion medium were dispersed using a sand mill, and this was dispersed in aluminum. A carrier-generating layer with a film thickness of 0.4 μm was formed by using a wire bar to form a carrier-generating layer on a polyester base on which 1 part of carrier transport material T-3 and borino-novo fu-1 resin were applied using a wire bar. (manufactured by Mitsubishi Gas Chemical Co., Ltd.); 1.3 parts, and as additives, 0.03 parts of Sanol LS-2626J (manufactured by Sankyo Co., Ltd.), a trace amount of silicone oil rKF-54J (manufactured by Shin-Etsu Chemical Co., Ltd.), 1.2 parts. - Dichloroethane: A solution dissolved in 10 parts was coated using a blade coater and dried to form a carrier transport layer with a film thickness of 18 μm.The thus obtained photoreceptor is referred to as Sample 1.

Example 2 1 part of the titanyl 7-thalocyanine shown in FIG. 8 obtained in Synthesis Example 2 and 100 parts of chloroform as a dispersion medium were dispersed using an ultrasonic dispersion device. On the other hand, polyamide resin rcM8000 is made on a polyester base coated with aluminum.
(manufactured by Toshisha) with a thickness of 0.2 μm,
The previously obtained dispersion was applied thereon by dip coating to form a carrier generation layer with a thickness of 0.3 μm.

Next, 1 part of carrier transport substance T-2 and polycarbonate resin [Panlite K1300J (manufactured by Ondai Kasei Co., Ltd.);
1.3 parts and a trace amount of silicone oil rKF-54) (
A solution obtained by dissolving 1,2-dichloroj2tan (manufactured by Shin-Etsu Chemical Co., Ltd.) in 10 parts of 1,2-dichloroj2thane was applied by dip coating, and after drying, a carrier transport layer having a thickness of 23 μm was formed.

The photoreceptor thus obtained is designated as sample 2.

Example 3 A photoreceptor was prepared in the same manner as in Example 2, except that the titanyl phthalocyanine obtained in Synthesis Example 3 was used in place of the titanyl phthalo/anine shown in FIG. This is called sample 3.

Comparative Example (1) Example 1 except that the titanyl 7-talonanine 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 (1). A comparative photoreceptor was obtained in the same manner as described above. This will be referred to as comparative sample (1).

Comparative Example (2) Comparative photosensitization was carried out in the same manner as in Example 2 except that the titanyl phthalocyanine shown in Fig. 7 obtained in Comparative Synthesis Example (2) was replaced with the X-ray circuit shown in Fig. 10. I got a body. 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 μ, and the surface potential Va immediately after charging and the surface potential Vi after being left for 5 seconds were determined, and then the surface illuminance was set to 2 (
lux), and the surface potential was set to 1/2V.
The exposure amount E172 required to obtain i was determined. Also D-1
The dark decay rate was determined from the formula 00(Va-Vi)/Va(%). The results are shown in Table 1. By reducing the chlorine content, a comparative titanyl phthalocyanine having particularly excellent potential retention properties can be obtained.

Table 1

[Brief explanation of drawings]

1 to 6 are cross sections showing specific examples of the layer structure of the photoreceptor of the present invention. FIGS. 7 and 8 are X-ray diffraction diagrams of titanyl phthalocyanine according to the present invention, and FIGS. 9 and 10 are X-ray diffraction diagrams of titanyl phthalocyanine obtained in comparative synthesis examples. ■... Conductive support 2... Carrier generation layer 3.
-Carrier transport layer 4.4'4''...Photosensitive layer 5...Intermediate layer

Claims (3)

[Claims] (1) In an amorphous crystalline state in which the X-ray diffraction spectrum for Cu-Kα rays shows a broad peak in the region of 6.5° ± 7.5° of the Bragg angle 2θ, the chlorine content is 0.2 wt. % or less of titanyl phthalocyanine. (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.