JPH04174442A - Electronic photograph photosensitive body - Google Patents

Abstract

PURPOSE:To offer a photosensitive body at which electrification is excellent and high sensitivity is possessed and potential stability at the time of repeated use is high and also the mechanical durability and surface smoothness of an electronic photograph photosensitive body photosensitive layer are excellent and picture quality lowering and sensitivity reduction are rare, by containing specific titanyl phthalocyanine pigment at a carrier generating layer and specific polycarbonate at a carrier transport layer. CONSTITUTION:At an electronic photograph photosensitive body that consists of a conductive base body on which an electric charge generating layer and an electric charge transport layer are accumulated in layers in order, the carrier generating layer contains titanyl phtalocyanine pigment, and the carrier transport layer contains polycarbonate that possesses as a principal repetition unit a structure unit expressed by a usual formula B. It is preferred that the above titanyl phtalocyanine is titanyl phthalocyanine of a crystallized condition at which at least the peak strength of 9.6+ or -0.2 deg. Bragg angle 2theta is more than 40% of the peak strength of 27.2+ or -0.2 deg., at an X-ray diffraction spectrum against Cu-Kalpha rays (wave length 1.54A).

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an electrophotographic photoreceptor, and an electrophotographic photoreceptor that is particularly used in printers, copiers, etc. and is particularly effective against LED light and semiconductor laser light. It is related to.

[Prior art]

Conventionally, electrophotographic photoreceptors sensitive to visible light have been widely used in copying machines, printers, and the like.

As such electrophotographic photoreceptors, inorganic photoreceptors provided with a photosensitive layer containing an inorganic photoconductive substance as a main component such as selenium, zinc oxide, or sulfurized domiwam are widely used. However, such inorganic photoreceptors do not necessarily satisfy the characteristics such as photosensitivity, thermal stability, moisture resistance, and durability required of electrophotographic photoreceptors for copying machines and the like.

For example, since selenium crystallizes due to heat or fingerprint stains when touched, the above-mentioned characteristics as an electrophotographic photoreceptor tend to deteriorate.

Furthermore, electrophotographic photoreceptors using cadmium sulfide have poor humidity resistance and durability, and electrophotographic photoreceptors using zinc oxide have problems in durability. Further, electrophotographic photoreceptors made of selenium or cadmium sulfide have severe restrictions in manufacturing and handling.

In order to improve the problems of such inorganic photoconductive materials, attempts have been made to use various organic photoconductive materials in the photosensitive layer of electrophotographic photoreceptors, and active research and development is currently underway. It is being said.

For example, Japanese Patent Publication No. 10496/1983 describes an organic photoreceptor having a photosensitive layer containing poly-N.hinylcarbazole and 2,4,7-)linitro-9-fluorenone. However, this photoreceptor also has insufficient sensitivity and durability. Therefore, a functionally separated electrophotographic photoreceptor has been developed in which the photosensitive layer is divided into two layers, a carrier generation layer and a carrier transport layer are separately configured, and each layer contains a carrier generation substance and a carrier transport substance.

This is because the carrier generation function and the carrier transport function can be assigned to different substances, and the substances that exhibit each function can be selected from a wide range of materials. The body can be obtained relatively easily. Therefore, it is expected that organic photoreceptors with high sensitivity and durability can be obtained.

Many substances have been proposed as carrier generating substances that are effective for the carrier generating layer of electrophotographic photoreceptors that achieve such functional separation.

Examples of using inorganic substances include, for example, Japanese Patent Publication No. 43-16
Examples include amorphous selenium as described in No. 198. This carrier generation layer containing amorphous selenium is used in combination with a carrier transport layer containing an organic carrier transport substance. However, as described above, this carrier generation layer made of amorphous selenium has the problem that it is crystallized by heat or the like and its properties deteriorate.

In addition, when forming an image using a semiconductor laser using an organic substance as the above-mentioned carrier-generating substance, 750
It is necessary to have high sensitivity to ~850 μm.

Among these, phthalocyanine compounds, which are one of the organic photoconductive materials, are known to have a photosensitive range extending to longer wavelengths than other compounds.

Examples of these phtaxyanine compounds exhibiting photoconductivity include JP-A-61-239248 and JP-A-64-170.
Examples include a-type titanyl phthalocyanine described in No. 66 and Japanese Patent Application No. 63-286537.

This a-type titanyl 7-lycyanine is Cu KCl, 5
The Bragg angle for 41 people's X-rays is 7.5°.

12.3', 16.3'', 251@, 28.7''
It has a peak at

However, this 0g titanyl phthalocyanine has low sensitivity, poor potential stability for repeated use, and is prone to fogging in an electrophotographic process using reversal development.

Furthermore, when used repeatedly, the reproducibility of fine lines deteriorates due to the occurrence of scratches on the surface of the photoreceptor and image blur due to ozone, etc., and in the case of digital images formed by dot exposure, the original quality (gradation, resolution) deteriorates.

This is particularly noticeable in digital image exposure of 400 dpi or higher.

On the other hand, the photoreceptor is subjected to removal of adhered toner, neutralization of static electricity, and surface cleaning, and is used repeatedly over a long period of time. Therefore, as an electrophotographic photoreceptor, it not only has electrophotographic properties such as good charging characteristics and sensitivity, and low dark decay, but also physical properties such as printing durability after repeated use, abrasion resistance, and moisture resistance. or,
Good resistance to ozone generated during corona discharge, ultraviolet rays during exposure, etc. (environmental resistance) is also required.

Conventionally, the functionally separated organic photoreceptor has been used mainly for negative charging, and as described in JP-A No. 60-247647, a thin carrier generation layer is provided on the support, and a relatively thick carrier transport layer is provided on the support. A structure is adopted in which layers are provided. The binders used for such photoreceptors include:
It is well known that bisphenol AI polycarbonate represented by the following structural formula exhibits good properties in terms of charging properties, sensitivity, residual potential, repeatability, etc.

Wrinkle 3 However, as a result of studies conducted by the present inventors, the solution of the above-mentioned bisphenol A polycarbonate tends to gel due to the high crystallinity of the polymer, and becomes unusable in about 1 to 2 days. It has the following drawbacks. In addition, when film formation is performed by coating, crystalline polycarbonate is likely to precipitate on the film surface during coating film formation, resulting in convex portions. When used as a body, convex portion i: Toner adheres and remains without being cleaned, which tends to cause image defects due to so-called poor cleaning.

Furthermore, when an electrophotographic photoreceptor using the above-mentioned hisphenol A type polycarbonate as a binder resin is used as a photoreceptor in an electrophotographic copying machine, the surface of the photosensitive layer may be scratched by a magnetic brush or a cleaning blade. It has the disadvantage that the photosensitive layer gradually wears out.

On the other hand, high image quality and smooth copying workability also depend on the quality of the smooth, homogeneous surface of the photoreceptor with uniform thickness. , Yuzuki skin caused by dryness, pinholes, application streaks,
Film surface failures such as cracks (rubent cracks) are a major problem in terms of copying characteristics and production technology.

In addition, surfactants are also useful for improving surface properties or slipperiness, and are effective for dispersing suspended solids and improving dispersion stability in suspension-based paints, and for solution-based paints. It also has value in terms of production technology, such as promoting dissolution and improving coating properties. However, if the type is incorrectly selected, poor adhesion between layers, breakdowns due to deterioration, or problems with moisture resistance often occur.

In order to deal with the above-mentioned problems, introduction of a substituent having fluorine on the carbon between the phenylene rings (Japanese Patent Application Laid-Open No. 63-65444'
t), substitution of an alkyl group or halogen electron on a phenylene ring (JP-A No. 148263/1983), or a copolymer of monomers in which both phenylene rings are substituted with a phenyl group or a ncrohekynyl group (JP-A-1-269942) No., Ifl
1-269943) or the combined use of distyryl as a carrier transport substance in bisphenol Z-type recarbonate (Japanese Patent Application Laid-Open No. 64-32265°), but these methods still have insufficient surface strength and surface smoothness. There is no gender,
It is susceptible to wear and scratches, and image quality deteriorates with repeated use.
In addition, there are still problems such as a decrease in sensitivity due to a decrease in film thickness due to wear.

[Purpose of the invention]

Therefore, the object of the present invention is to provide a photosensitive layer of an electrophotographic photoreceptor with good charging properties, high sensitivity, high potential stability during repeated use, and good mechanical durability and surface smoothness.
To provide a photoreceptor with less deterioration in image quality and less loss of sensitivity.

[Hakhu composition]

The object of the present invention is to provide an electrophotographic photoreceptor in which a charge generation layer and a charge transport layer are sequentially laminated on a conductive substrate,
The carrier generation layer is exposed to Cu-Ha characteristic X-rays (wavelength: 1.5
4), the carrier transport layer contains a titanyl phthalonanine pigment whose main peaks in the Bulla-2g angle 2θ are at least 9.6 ± 0.2° and 27.2 ± 0.2', and the carrier transport layer This is achieved by an electrophotographic photoreceptor characterized by containing a polycarbonate having a structural unit represented by the general formula CB) as a main repeating unit.

General formula CB) In the formula, Z is the following two substituted or unsubstituted groups; a nonmetallic atomic group necessary to form a carbocyclic group or a heterocyclic group, R1,
R2+R3+R1 and Rs, R6, R+, and Rl represent a hydrogen atom, a chlorine atom, a bromine atom, or a methyl group.

However, not all of them are hydrogen atoms.

Furthermore, in an aspect of the present invention, the titanyl phthalocyanine has at least a Bragg angle of 2θ of 9.5 mm in an X-ray diffraction spectrum for Cu-Ka rays (wavelength: 1.54 mm). It is preferable that the crystalline titanyl phthalocyanine has a peak intensity of '610.2' that is 40% or more of the peak intensity of 27.2±0.2°.

Further, when dot exposure is performed in electrophotographic image formation using the photoreceptor of the present invention, it is preferable to perform the development treatment with a developer containing toner particles having a weight average particle diameter of 8 μm or less.

The peak in titanyl phthalocyanine is a distinct sharp protrusion that is different from noise.

The basic structure of the titanyl phthalonanine of the present invention is represented by the following general formula.

General formula: x', x2. x 3. x 'H hydrogen atom, /
% O represents a care atom, alkyl group, or alkoxy group; n.

m, 12. k represents an integer from 0 to 4.

The above X-ray diffraction spectrum was measured under the following conditions.

X-ray tube Cu voltage 40. OKV current
100 mA start angle 6.0
0 degrees.

Stop angle 35.00 deg.

Step angle 0.020 deg.

Measurement time: 0.50 sec.

Also, the above X-ray diffraction spectrum is r JDX-8200
J (manufactured by JEOL Ltd.).

The method for producing the titanyl phthalocyanine according to the present invention will be explained next. For example, 1,3-diiminoisoindoline and sulfolane are mixed, titanium tetrapropoquine is added thereto, and the mixture is reacted under a nitrogen atmosphere. The reaction temperature is 80°C to 300°C, particularly preferably 100°C to 260°C. After the reaction is completed, the precipitate is collected by filtration after being left to cool to obtain titanyl phthalonanine.

Next, by treating this with a solvent, the first and second sections
Crystalline titanyl phthalocyanine exhibiting the properties shown in the figure can be obtained.

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

In the present invention, other carrier-generating substances (hereinafter referred to as CGM) may be used in combination with the above titanyl phthalocyanine. Such CGMs include those different in crystal form from the titanyl phthalocyanine of the present invention, such as β-type and β-type.
In addition to titanyl phthalocyanine of type, a-type, β-mixed type, and amorphous type, other phthalocyanine pigments, azo pigments, anthraquinone pigments, perylene pigments, polycyclic quinone pigments, and squareium pigments are included.

A carrier transport material (hereinafter referred to as CTM) in the photoreceptor of the present invention
A variety of compounds can be used as (expressed as), but typical examples include nitrogen-containing heterocyclic nuclei and fused ring nuclei thereof such as oxazole, oxadiazole, thiazole, thiadiazole, imidazole, etc. compounds, polyarylalkane compounds, pyrazoline compounds, hydrazone compounds, triarylamine compounds, styryl compounds, styryltriphenylamine compounds, a-phenylstyryltriphenylamine compounds, butadiene compounds, hexatrune compounds Compound,
Examples include carbazole compounds and fused polycyclic compounds. These CTII! Although there are many specific examples including CTM described in JP-A-61-107356, the structure of a particularly typical one is shown below.

C,H.

Next, the electrophotographic photoreceptor of the present invention is coated with a transport layer (hereinafter referred to as C).
The binder resin contained in the binder resin (represented as TL) is represented by the following general formula (,
A polymer containing the repeating unit represented by B) as a main structural composition will be explained.

General formula (B) In the formula, Z is the following two substituted or unsubstituted groups; a nonmetallic atomic group necessary to form a carbocyclic group or a heterocyclic group, Rl,
R, , Rs, R and Rs, Rs, R+, Ra represent a hydrogen atom, a chlorine atom, a bromine atom, or a methyl group.

However, not all of them are hydrogen atoms.

The degree of polymerization is 10-5000, preferably 50-1000.

These carbonate resins have improved the drawbacks of conventionally used bisphenol A type carpoints, and since a Z ring is formed on the central carbon atom of these polycarbonates, The molecular chains are effectively prevented from aligning in a particular direction. This prevents the polycarbonate from crystallizing, causing the solution to gel, or precipitating on the film surface during the formation of the photosensitive layer, thereby preventing property deterioration such as a decrease in yield due to abnormal convexities and image defects due to poor cleaning. be able to.

This I: The ring formed by 2 in the general formula (B) directly contributes to the remarkable effect.

That is, in the present invention, by using the polycarbonate represented by the general formula (B) as a binder resin, the film has excellent physical properties, excellent electrophotographic properties such as charge retention and sensitivity residual potential, and can be used repeatedly. It is possible to create an electrophotographic photoreceptor that exhibits stable characteristics with little fatigue deterioration even when exposed to various conditions.

Furthermore, when used as a photoreceptor, the surface of the photosensitive layer may be scratched even if rubbed with a magnetic bra or cleaning blade.
<<It is possible to create an electrophotographic photoreceptor with high printing durability, which has less abrasion of the photosensitive layer and has no characteristic defects such as poor cleaning.

The polycarbonate resin of the present invention is easily synthesized using a phenol compound represented by the following general formula, for example, according to a conventional method.

In the formula, Z is the following two substituted or unsubstituted groups; a group of nonmetallic atoms necessary to form a carbocyclic group or a heterocyclic group, Rl+
R,, R3, R4 and RS+RM, R+, Ra are
-Represents a hydrogen atom, a chlorine atom, a bromine atom, or a methyl group.

However, not all of them are hydrogen atoms.

To illustrate the method for producing the polycarbonate resin of the present invention, specifically, in the presence of an inert solvent such as methylene chloride or 1,2-dichloroutane, the above-mentioned funinol compound is added to the
Add an alkaline aqueous solution or pyridine as an acid acceptor,
An example is a method of reacting while introducing phosgene.

When using an alkaline aqueous solution as an acid acceptor, the reaction rate can be increased by using a sugar tertiary amine such as trimethylamine or triethylamine, or a quaternary ammonium compound such as tetrabutylammonium chloride or benzyltributylammonium bromide as a catalyst. do.

Phenol, p-
Monohydric phenol such as 1-butylphenol may also be present. The catalyst may be added from the beginning, or any method may be used, such as adding it after the oligomer is produced to increase the molecular weight.

Further, the polycarbonate resin according to the present invention may optionally contain a co-condensation type polycarbonate containing other repeating units in addition to the repeating units of general formula (B), such as 4.
Using polycarbonate made by co-condensing 4'-dihydroxy-3-methylphenyl-1,1-cyclohexane with a small amount of bisphenol A, the physical, chemical, or electrical properties can be adjusted. Good too.

More needed! : Other polymers may be mixed and used within a range that does not interfere with the desired effect. The mixing ratio at this time is preferably 50 wt/% or less.

Since the binder used in the present invention is polycarbonate-based, it can provide the photoreceptor with the excellent charging performance, repeatability, printing durability, etc. that polycarbonate inherently exhibits.

Next, the groups R3 to R in the general formula (B) may be a hydrogen atom, a halogen atom, or an alkyl group such as a methyl group.

In the polycarbonate I of the general formula (B), 2 may form a 5- or 6-membered carbocyclic ring or a heterocyclic ring, such as a nclohexyl ring, a /clopentyl ring, etc. A substituent such as an acetyl group or an acetylamino group may be introduced into a part of the ring.

Specifically, the repeating nest positions of the polycarbonate used in the present invention include the following.

Exemplary B repeating units B-9 B-10 B-13 Among these, polycarbonates with repeating structures shown in B-3 and B-6 have particularly excellent mechanical durability.

Examples of binders that may be used in combination with the polycarbonate used as the binder described above include the following.

(1) Polyester (2) Methacrylic resin (3) Acrylic resin (4) Polyvinyl chloride (5) Polyvinylidene chloride (6) Polystyrene (7) Polyvinyl acetate (8) Styrene copolymer resin (e.g. styrene-butadiene copolymer) (9) Acrylonitrile copolymer resin (e.g., vinylidene chloride-acrytronitrile copolymer, etc.) (10) Vinyl chloride-vinyl acetate copolymer (11) ) Vinyl chloride-vinyl acetate-maleic anhydride copolymer (12) Silicone resin (13) Silicone-alkyd resin (14)
Phenolic resins (e.g., phenol-formaldehyde resins, cresol formaldehyde resins, etc.) (15) Styrene-alkyd resins (16)
Poly-N-vinylcarbazole (17) Polyvinyl butyral (18) Polyvinyl formal (19) Polyhydroxystyrene These binders can be used singly or as a mixture of two or more in combination in the carbonate according to the present invention.

Further, in the present invention, in the development during the dot exposure,
Since the particle size of the toner used is 8 μm or less in weight average particle size, the toner adheres well to the electrostatic latent image, corresponding to the reduction in dont area due to the increase in the number of dots to 600 dpi or more. It can be manifested in. In other words, if the toner particle size exceeds 8 uffl, it becomes too large and does not adhere well to a small latent image, and the amount of toner adhesion decreases, resulting in insufficient gradation and resolution. , such a problem does not occur with the toner having the particle size of the present invention.

In addition, in the above, the number of dots during dot exposure is further 60.
It is preferable that the toner has a particle size of 0 to 1800 dpi, and that the particle size of the toner used during development is 8 to 2 .mu.m.

Examples of the dispersion medium for the organic pigment used in the present invention include hydrocarbons such as hexane, benzene, toluyune, and quintin, methylene chloride, methylene bromide, 1.
2-dichloroyutane, 5yn-tetrachloryutane,
cis-1,2-; Chlorethylene, 1゜1.2-trichloroethane, Ll, 14-trichloroethane, 1.2-
Halogenated hydrocarbons such as dichloropropane, chloroform, bromoform, chlorobenzene, ketones such as acetone, methylbutylketone, cyclohexanone, nistyls such as ethyl acetate, butyl acetate, methanol, ethanol, propatool, butanol, / Alcohols and their derivatives such as clohexanol, heptatool, ethylene glycol, methyl cellosolve, ethyl cellosolve, acetic cellosolve, ethers such as tetrahydrofuran, 1,4-dioxane, furan, furfural, acetals, pyridine, butylamine, stylamine, ethylenediamine, Amines such as inpropatur amine, N
In addition to nitrogen compounds such as amides such as , N-dimethylformamide, fatty acids and phenols, carbon disulfide and triethyl phosphate, and phosphorus compounds may be mentioned.

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

Examples of electron-accepting substances that can be used for Uni include succinic anhydride, maleic anhydride, dibromaleic anhydride, phthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, 3-nitrophthalic anhydride, 4
-Nitrophthalic anhydride, pyromellitic anhydride, mellitic anhydride, tetracyanoethylene, tetraanoquinodimethane, Q-dinitrobenzene, m-dinitrobenzene,
1,3.5-trinitrobenzene, paranitrobenzonitrile, bikudyl chloride, quinone chlorimide, chloranil, puryanil, dichlorodicyanobarabenzoquinone, anthraquinone, dinitroanthraquinone, 2.
7-cyclohexanone, 2,4.7-trinitrofluorenone, 2.4.5.7-tetranitrofluorenone, 9-fluorenylidene [zineanomethylenemalonodinitrile], polynitro-9-fluorenylidene-[zineanomethylenemalonodinitrile] Nitrile], picric acid, 0-nitrobenzoic acid, p-nitrobenzoic acid, 3.5-dinitrobenzoic acid, pentafluorobenzoic acid, 5-nitrosalicylic acid, 3.5-dinitrosalicylic acid, phthalic acid, mellitic acid, etc. Compounds with high electron affinity can be mentioned. In addition, the addition ratio of the electron-accepting substance is 10 to 10% by weight of the organic pigment/electron-accepting substance used in the present invention.
0:0.011-200, preferably 100:0
．． It is 1-100.

The proportion of electron-accepting substances added to such a layer is based on the weight ratio of total C.
TM: Electron accepting substance-100: 0.01-100
, preferably 100:0.1-50.

Further, organic amines can be added to the photosensitive layer of the present invention for the purpose of improving the charge generation function of CGII, and it is particularly preferable to add a secondary amine.

These compounds are described in JP-A-59-218447 and JP-A-62.
It is described in No.-8160.

In addition, 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.

Further, the protective layer according to the present invention may contain less than 5 Qwt% of a thermoplastic resin, if necessary, for the purpose of improving processability and physical properties (preventing cracks, imparting flexibility, etc.).

The intermediate layer functions as an adhesive layer or a blocking layer, and in addition to the binder resin, it may contain, for example, hapolyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride. Acid copolymers, casein, N-alkoxymethylated nylon, starch, etc. are used.

As the conductive support used in the construction of the electrophotographic photoreceptor of the present invention, the following are mainly used, but the support is not limited thereto.

l) Metal plates such as aluminum plates and stainless steel plates.

2) A thin layer of metal such as aluminum, palladium, or gold is provided on a support such as paper or plastic film by lamination or vapor deposition.

3) A layer of a conductive compound such as a conductive polymer, indium oxide, or tin oxide is provided on a support such as paper or a plastic film by coating or vapor deposition.

As shown in FIGS. 3 and 4, the photoreceptor of the present invention includes a carrier generation layer (hereinafter referred to as CGL) 2 containing CGIj as a main component and a CTL containing CTM as a main component on a conductive support 1. A photosensitive layer 4 made of a laminate of 3 and 3 is provided.

As shown in FIG. 4, this photosensitive layer 4 may be provided on the conductive support 1 via an intermediate layer 5.

When the photosensitive layer 4 has a two-layer structure in this manner, an electrophotographic photoreceptor having the best electrophotographic properties can be obtained.

Furthermore, a protective layer may be provided on the photosensitive layer 4 if necessary.

Further, the CGL 2 constituting the photosensitive layer 4 having a two-layer structure is prepared by forming an I-contact on the conductive support l or by providing an intermediate layer such as an adhesive layer or a blocking layer as necessary, and then applying the following method. Can be formed.

(1) Vacuum deposition method (2) Method of applying a solution of CGM dissolved in a suitable solvent (3) Forming ccM into fine particles in a dispersion medium using a ball mill, sand grinder, etc. and adding a binder if necessary. A method of applying a dispersion obtained by mixing and dispersing.

That is, specifically, vapor deposition methods such as true vapor deposition, sputtering, and CVD, or dipping, spray, blade,
Application methods such as roll methods are optionally used.

The thickness of CGL2 formed in this way is 0.01
It is preferably ~5 μm, more preferably 0.05 ~
It is 3 μm.

Further, the thickness of the CTL 3 can be changed as necessary, but it is usually preferably 5 to 30 μm. This CTL 3
The composition ratio is preferably 0.1 to 5 parts by weight of the binder to 1 part by weight of the CTM.

Further, when CGL is configured as a dispersed type in a binder, it is preferable to use the binder in an amount of 5 parts by weight or less per 1 part by weight of CCM.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Synthesis examples of various titanyl phthalonanine pigments will be described.

(Synthesis Example 1) 29.2 g of 1,3-diiminoisoindoline and 200 ml of sulfolane were mixed, 17.0 g of titanium tetrane propoxide was added, and the mixture was heated at 140°C under a nitrogen atmosphere for 2 hours.
Allowed time to react. After cooling, the precipitate was collected by filtration, washed with chloroform, washed with 2% aqueous hydrochloric acid, washed with water, and washed with methanol. After drying, 25.5 g (88.5%) of titanyl 7-talocyanine was obtained. .

The product was dissolved in 20 times the amount of concentrated sulfuric acid, poured into 100 times the amount of water to precipitate it, and after filtering, the wet cake was dissolved in 1.
The first mixture was heated in 2-dichloroethane at 50°C for 10 hours.
A crystal form having the X-ray diffraction spectrum shown in Figure (a) was obtained. The peak intensity of this crystal at a Bragg angle of 2θ of 9.6″ was 102% of that at 272°.

(Synthesis Example 2) 29.2 g of 1,3-diiminoisoindoline and 200 m (l) of sulfolane were mixed, 17.0 g of titanium tetraisopropoxide was added, and the mixture was heated at 140°C under a nitrogen atmosphere for 2 hours.
Allowed time to react. After cooling, the precipitate was collected by filtration, washed with chloroform, washed with 2% aqueous hydrochloric acid, washed with water, and washed with methanol. After drying, 25.5 g (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 to precipitate it, and after filtering, the wet cake was dissolved in 1.
After stirring in 2-dichloroethane at room temperature for 1 hour,
b) A crystal form with the X-ray diffraction spectrum shown in I;

This crystal has a peak intensity of 9.6° with a Bragg angle of 2θ of 2
At 75% of that of 72°.

(Synthesis Example 3) 25.6 g of phthalodinitrile and 1 σ-chlornaphthalene
6.5 mg of titanium tetrachloride was dropped into the 50 mΩ mixture under a nitrogen stream, and the mixture was reacted at a temperature of 200 to 220° C. for 5 hours. The precipitate was collected by filtration, washed with α-chlornaphthalene, then with chloroform, and then with methanol. Next, the mixture was refluxed in ammonia water to complete hydrolysis, washed with water, methanol, and dried to yield 218 g (75.6%) of titanyl phthalonanine.

The product was dissolved in 10 times the amount of concentrated sulfuric acid, poured into 100 times the amount of water to precipitate it, and after filtering, the total wet cake was 1.
The crystal obtained by stirring 2-dichloroutane at room temperature for 1 hour has a peak intensity of 9.6° in Bragg angle 2θ of 27.
It is 45% of that of 2'.

(Comparative synthesis example 1) 25.6 g of phthalodinitrile and 1 σ-chlornaphthalene
6.5 mg of titanium tetrachloride was added dropwise to the mixture of 50+r and Q under a nitrogen stream, and the mixture was 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. The mixture was then refluxed in ammonia water to complete hydrolysis, washed with water, methanol, and dried to obtain 21.8 g (756%) of titanyl phthalonanine.

The product was dissolved in 10 times the volume of concentrated sulfuric acid, poured into 100ml of water to precipitate it, and after filtering, the wet cake was washed.
The crystals obtained by stirring diklebenzene at room temperature for 1 hour are
In the line diffraction spectrum, the peak intensity at Bragg angle 2θ of 9.6a was 35% of that at 27.2″.

(Comparative Synthesis Example 2) After drying the wet cake of Synthesis Example 1, β-type titanyl phthalonanine was obtained by heating and stirring using a-chloronaphthalene.

Example 1 3 parts of copolyamide F Laccamite 5003 (manufactured by Dainippon Ink Co., Ltd.) (parts indicate parts by weight; the same applies hereinafter) was heated and dissolved in 100 parts of methanol, filtered through a 0.6μ box filter, and then immersed. It was coated on an aluminum drum by a coating method to form a subbing layer with a thickness of 05 μm.

On the other hand, 3 parts of titanyl phthalonanine having the X-ray diffraction pattern obtained in Synthesis Example 1, Nricorn resin r KR-5240, 15% xylene/
Butanol Solution (manufactured by Shin-Etsu Chemical Co., Ltd.) A solution prepared by dispersing 3 parts of solid content and 100 parts of methyl isobutyl ketone as a dispersion medium using a sand mill was applied onto the previous subbing layer by dip coating, and the film was coated. A CGL with a thickness of 0.2 μm was formed.

Then, a portion of CT~(1), Exemplary Resin rB-3''1.
5 parts, a trace amount of silicone oil r KF-54J (manufactured by Shin-Etsu Chemical Co., Ltd.) dissolved in 1.21 parts of dichloroethane was applied by dip coating, and after drying, a carbon film with a film thickness of 25 μm was applied.
TL was formed. The photoreceptor thus obtained is referred to as Sample 1.

Examples 2 to 5 4 was carried out in the same manner as in Example 1, except that the types of CGAI+ and the types of resins of CGL and CTL were shown in Table-1.
Various types of photoreceptors were obtained and these were designated as Samples 2 to 5.

Comparative Examples (1), (2), (3) Types of CGfi and CGL and CTL resins Three types of photoreceptors were obtained and these were used as a comparative sample (1).

The resins used were as follows.

・Silicone resin r KR-5240J (manufactured by Shin-Etsu Chemical Co., Ltd.) ・Polyvinyl butyral "ESRESOTSUKU BM-SJ"
(Manufactured by Tanezu Kagaku Co., Ltd.) ・Polycarbonate “Panlite L-1250J (
(manufactured by Ondai Kasei Co., Ltd.) (Evaluation) Samples 1 to 6 and comparative samples (1) and (2) were subjected to r [1
- Bix 2025j (manufactured by Konica) (equipped with a semiconductor laser light source) was installed in a modified machine and made 50,000 continuous copies. Adjust the grid voltage V so that the unexposed area potential V□ is -600 [V], measure the exposed area potential (■) when irradiated with 0.7 mW, and further calculate the residual potential V after copying is completed. was measured. Further, reversal development was performed at a developing bias of -560 [V], and the gradation and resolution of the copied images at the initial stage and after 50,000 continuous copies were evaluated as follows. - Image evaluation machine is ll-Bix 2025 (manufactured by Konica)
It can be developed using reverse development, is equipped with a semiconductor laser light source, and has 300dpi, 400dpi, and 600dp.
I modified the i to write on the photoreceptor, and made the following evaluation: *1.

(a) Gradation image density is 0, 0.1° and 0.2 respectively in area ratio of halftone dots.
．． 0.3.0, 4.0.5.0.6.0.7.1.0.
A print roller having an image mode capable of discriminating densities in lθ stages of 1.25 was connected, and it was evaluated how many stages ff11 of printed images could be determined.

(b) Resolution 2, 3, 4, 5, 6, 7, and 8 equally spaced vertical lines per 1+u+ were provided on the printed image, and the grade in which the vertical lines could be distinguished was displayed as the resolution. .

<Evaluation Example 1> An evaluation machine was equipped with a 300 dpi optical system, and a toner with a weight average particle diameter of 8 μm was used as the developer toner.

The results are shown in Table 2 below. According to this, when the exposure dot is 300 dpi, even if the titanyl phthalocyanine of the present invention is used in both gradation and resolution in the initial image, a sufficient difference in effect is still not observed.

Evaluation Example 2> The evaluation machine was equipped with a 400 dpi optical system, and the other aspects were the same as in Evaluation Example 1. The results are shown in Table 3 below, and when the dot exposure reached 400 dpi, the gradation and resolution of samples 1 to 5 and comparative sample (1) in the initial image decreased.
In this case, the l rank increases compared to the case of 300 dpi, but in comparison samples (2) to (3), it remains at the same level as 300 dpi.

Furthermore, in samples 1 to 5, even after 50,000 copies were completed, no decrease in gradation or resolution was observed compared to the initial image.

Evaluation example 3> The evaluation machine was equipped with a 600 dpi optical system, and the rest were the same as evaluation example 1.
I did the same thing. The results are shown in Table 4 below, and when the number of exposed dots was reduced to 600 dpi, samples 1 to 1
5, even after 50,000 copies were completed, results were obtained that were significantly better in terms of gradation and resolution than with conventionally known photoreceptors.

〔Effect of the invention〕

In the present invention, as described above, by using the titanyl phthalocyanine, it is possible to obtain an electronic photoreceptor that is particularly effective against LED light and semiconductor laser light.

Furthermore, the electrophotographic photoreceptor of the present invention is characterized by excellent sensitivity, charging ability, potential stability, and mechanical durability.

In particular, the surface smoothness of the photosensitive layer is good even during repeated use, and the image quality deteriorates little.

[Brief explanation of drawings]

FIG. 1 is an X-ray diffraction spectrum diagram of titanyl phthalocyanine used in the photoconductor, FIG. 2 is a spectral absorption spectrum diagram thereof, and FIGS. 3 and 4 are cross-sectional views of embodiments of the photoconductor of the present invention. 1... Conductive support 2... Carrier generation layer 3
...Carrier transport layer 4...Photosensitive layer 5...Intermediate layer

Claims (3)

[Claims] (1) In an electrophotographic photoreceptor in which at least a carrier generation layer and a carrier transport layer are laminated in this order on a conductive support, the carrier generation layer has Cu-Kα characteristic X-ray (
The carrier transport layer contains a titanyl phthalocyanine pigment whose main peaks of the Bragg angle 2θ with respect to a wavelength of 1.54 Å are at least 9.6 ± 0.2° and 27.2 ± 0.2°, and the carrier transport layer has the following general formula ( An electrophotographic photoreceptor comprising a polycarbonate having a structural unit represented by B) as a main repeating unit. General formula (B) ▲ Numerical formulas, chemical formulas, tables, etc. are available▼ [In the formula, Z is the following two groups, substituted or unsubstituted; nonmetallic atomic groups necessary to form a carbocyclic group or a heterocyclic group, R_
1, R_2, R_3, R_4 and R_5, R_6, R_
7, R_8 represents a hydrogen atom, a chlorine atom, a bromine atom, or a methyl group. However, not all of them are hydrogen atoms. ] (2) The titanyl phthalocyanine has a Cu-Kα ray (
Titanium in a crystalline state in which the peak intensity at 9.6±0.2° of Bragg angle 2θ is at least 40% of the peak intensity at 27.2±0.2° in the X-ray diffraction spectrum for wavelength 1.54 Å). The electrophotographic photoreceptor according to claim 1, which is a phthalocyanine. (3) The electrophotographic photoreceptor according to claim 1 or 2, wherein dot exposure is performed in electrophotographic image formation, and development processing is performed with a developer containing toner particles having a weight average particle size of 8 μm or less.