JP3123184B2 - Novel crystal of dichlorotin phthalocyanine, method for producing the same, and electrophotographic photoreceptor using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel crystal and manufacturing method thereof useful dichlorotin phthalocyanine as a charge generating material, and relates to an electrophotographic photoreceptor using the same.
More specifically, the charge generating material to the binder resin constituting the photosensitive layer is a <br/> shall relates to a electrophotographic photoreceptor according to the particular combination.

[0002]

2. Description of the Related Art Phthalocyanines are used in paints, printing inks,
It is a useful material as a catalyst or an electronic material. In recent years, in particular, materials for electrophotographic photosensitive members, optical recording materials, and photoelectric conversion materials have been extensively studied. Regarding electrophotographic photoreceptors, in recent years, the photosensitive wavelength range of organic photoconductive materials proposed conventionally has been extended to the wavelength of near-infrared semiconductor lasers (780 to 830 nm), and as a photoreceptor for digital recording such as a laser printer. There is an increasing demand for its use. From this viewpoint, squarylium compounds (JP-A-49-105536 and JP-A-58-21) can be used.
416), triphenylamine-based trisazo compounds (JP-A-61-151659), and phthalocyanine compounds (JP-A-48-34189 and 57-1).
No. 48745) has been proposed as a photoconductive material for a semiconductor laser.

When an organic photoconductive material is used as a photosensitive material for a semiconductor laser, first, the photosensitive wavelength range extends to a long wavelength, and then, the sensitivity of the photosensitive member to be formed is determined.
Good durability is required. However, the above-mentioned organic photoconductive material does not sufficiently satisfy these conditions. In order to overcome these drawbacks, the relationship between the crystal type and the electrophotographic properties of the organic photoconductive material has been studied, and many reports have been made particularly on phthalocyanine compounds.

[0004] In general, phthalocyanine compounds exhibit a large number of crystal forms depending on the production method and treatment method, and it is known that this difference in crystal type greatly affects the photoelectric conversion characteristics of the phthalocyanine compound. Regarding the crystal form of the phthalocyanine compound, for example, when looking at copper phthalocyanine, in addition to the stable β form, α, ε, π,
Crystal forms such as x, ρ, γ, and δ are known, and it is known that these crystal forms can be mutually transformed by mechanical strain, sulfuric acid treatment, organic solvent treatment, heat treatment, and the like. (Eg, U.S. Pat. Nos. 2,770,629, 3,160,635, 3,708,292, and 3,357,989). Also, Japanese Patent Application Laid-Open
Japanese Patent Publication No. 0-38543 describes the relationship between the difference in crystal form of copper phthalocyanine and the electrophotographic sensitivity. Japanese Patent Application Laid-Open No. Sho 62-11947 describes an electrophotographic photoreceptor using dihalogenostin phthalocyanine as a charge generating material.
No. 57 describes a tin phthalocyanine compound having a specific diffraction peak in an X-ray diffraction spectrum and an electrophotographic photoreceptor using the same.

[0005]

However, the phthalocyanine compounds proposed hitherto have not been sufficiently satisfactory in light sensitivity and durability when used as a photosensitive material. Also, in the production thereof, there have been problems such as a complicated crystal type conversion operation and difficulty in controlling the crystal type. By the way, dichlorotin phthalocyanine has poor dispersibility and dispersibility when used by dispersing in a binder resin, and when used as a photoreceptor, there is a problem in sensitivity characteristics and charge retention, and image quality is poor. Defects such as fogging and black spots also occurred in the upper part, and did not have sufficiently satisfactory characteristics.

On the other hand, the conventionally proposed tin phthalocyanine compound has poor crystal form stability with respect to a solvent, and exhibits a crystal form when dispersed in a solvent and after a dispersion is applied to form a photosensitive layer. It could not be maintained for a long period of time, and when used as a charge generating material, it was still not satisfactory enough. That is, if the primary particle size of the dichlorotin phthalocyanine compound is too fine, the stability of the crystal form in the solvent is poor, and there is a problem that the crystal is easily transferred to another crystal form. Conversely, when the primary particle size increases, the sensitivity and stability of the electrophotographic photoreceptor formed by using the primary particle size decrease significantly. There is also a problem that the stability of the crystallinity of the dichlorotin phthalocyanine compound largely depends on the dispersion solvent. Regarding this point, the dichlorotin phthalocyanine crystal newly produced by the present inventors also has a disadvantage in that the stability of the crystal form with respect to the solvent is poor, and there is a difficulty that the crystal form is easily transferred to another crystal form. However, it is difficult for the electrophotographic photosensitive member to exhibit sufficient electrophotographic characteristics.

The present invention has been made to solve the above-mentioned problems in the prior art. That is, an object of the present invention is to provide a novel crystal of dichlorotin phthalocyanine useful as a charge generation material having sensitivity in a long wavelength region, and a method for producing the same. Another object of the present invention is to provide an electrophotographic photoreceptor having high sensitivity and durability by using the above-mentioned dichlorotin phthalocyanine crystal as a charge generation material, and further having more excellent sensitivity characteristics, sex is good, Ru der seeks to provide an improved electrophotographic photoreceptor of the image characteristics of the image quality with few defects.

[0008]

Means for Solving the Problems The present inventors have searched for a charge-generating material having excellent photosensitive characteristics, and have investigated the relationship between the charge-generating material and a binder resin and a dispersing solvent used in forming a photosensitive layer. I have been studying the combination. As a result, they have found that a novel crystal produced by subjecting dichlorotin phthalocyanine obtained by synthesis to a simple treatment is useful as a charge generation material. Further, the electrophotographic photoreceptor containing this novel crystal in the photosensitive layer has high sensitivity and durability, and when a specific resin is combined with the above crystal as a binder resin constituting the photosensitive layer, the photoreceptor becomes The present inventors have found that they have more excellent sensitivity characteristics, good charge retention characteristics, and few image quality defects without impairing the dispersibility of crystals and the applicability of the dispersion during the production.
Furthermore, the coating liquid for an electrophotographic photosensitive member comprising the novel crystal and a specific dispersing solvent can not only disperse the crystal in the solvent without changing the crystal form of dichlorotin phthalocyanine, The present inventors have found that since the crystal form of dichlorotin phthalocyanine in the photosensitive layer formed from the coating solution can be maintained for a long period of time, the above-described photosensitive characteristics unique to the novel crystal can be directly expressed. The present invention has been completed based on such findings.

That is, according to the present invention, the Bragg angle (2θ ± 0.2 °) in the X-ray diffraction spectrum is 8.5 °,
The novel crystals of dichlorotin phthalocyanine have strong diffraction peaks at 11.2 °, 14.5 ° and 27.2 °. At the same time, the present invention is a method for producing novel crystals of the above dichlorotin phthalocyanine by mechanically pulverizing dichlorotin phthalocyanine together with an inorganic salt or after pulverizing the dichlorotin phthalocyanine with a solvent. The present invention also relates to an electrophotographic photoreceptor obtained by coating a photosensitive support containing at least one kind of the above-mentioned dichlorotin phthalocyanine crystal on a conductive support, wherein the photosensitive layer comprises a dichlorotin phthalocyanine crystal and a polyvinyl acetal resin. , Vinyl chloride
Vinyl acetate copolymer, have in particular preferred that the phenoxy resin and modified ether type polyester selected from resins containing a binder resin consisting of at least one charge generation layer and a charge transport layer and sequentially stacked laminated structure .

Hereinafter, the present invention will be described in detail. In the X-ray diffraction spectrum of the present invention, the Bragg angle (2θ ± 0.
2 °) are 8.5 °, 11.2 °, 14.5 ° and 2
Dichlorotin phthalocyanine crystal having a strong diffraction peak at 7.2 ° is obtained by diclos phthalocyanine crystal synthesized by a known method using a ball mill, a mortar, an attritor,
It can be manufactured by mechanically pulverizing with a roll mill, a homomixer, a sand mill, a kneader or the like. In the pulverization, the use of a grinding aid for inorganic salts such as sodium chloride and sodium sulfate can be performed very efficiently, and the crystal form of the present invention having a uniform particle size can be transferred. The grinding aid is 0.5 to 20 times, preferably 1 to 20 times the dichlorotin phthalocyanine crystal.
Use up to 10 times. The present invention relates to mechanically pulverized dichlorotin phthalocyanine, toluene, dichloromethane,
Further solvent treatment may be carried out with an organic solvent such as tetrahydrofuran (THF) or methyl ethyl ketone (MEK). By this solvent treatment, it is possible to obtain the most preferred dichlorotin phthalocyanine crystal of the present invention, which has more crystallinity and particle size. it can. The solvent treatment may be performed while milling with grinding media such as glass beads and steel beads as necessary.

Next, an electrophotographic photosensitive member manufactured by using the dichlorotin phthalocyanine crystal obtained by the above-described processing method as a charge generating material in a photosensitive layer will be described. The electrophotographic photoreceptor of the present invention may have a single-layer photosensitive layer or a laminated structure in which a charge generation layer and a charge transport layer are functionally separated. When the photosensitive layer has a laminated structure, the charge generation layer is composed of the dichlorotin phthalocyanine crystal and a binder resin. 1 to 4 are cross-sectional views schematically showing the electrophotographic photosensitive member of the present invention. In FIG. 1, a photosensitive layer composed of a charge generation layer 1 and a charge transport layer 2 laminated thereon is coated on a conductive support 3. In FIG. 2, the charge generation layer 1
An undercoat layer 4 is interposed between the conductive layer 3 and the conductive support 3, and in FIG. 3, the surface of the photosensitive layer is covered with a protective layer 5. Further, in FIG. 4, both the undercoat layer 4 and the protective layer 5 are laminated. Hereinafter, the layers 1 to 5 will be described in detail while adding a description of the photosensitive layer having a single-layer structure in the middle.

The charge generation layer 1 in the electrophotographic photoreceptor of the present invention is prepared by dispersing the dichlorotin phthalocyanine crystal in a solution in which a binder resin is dissolved in an organic solvent to prepare a coating solution. It is formed by applying on the body 3 or the undercoat layer 4. The binder resin used can be selected from a wide range of resins. Preferred binder resins include, for example, polyvinyl acetal resins such as polyvinyl butyral resin, polyvinyl formal resin, partially acetalized polyvinyl butyral resin in which a part of butyral is modified with formal or acetoacetal, and polyarylate resin (bisphenol A). And phthalic acid), polycarbonate resins, polyester resins, modified ether type polyester resins, phenoxy resins, polyvinyl chloride resins, polyvinylidene chloride resins, polyvinyl acetate resins, polystyrene resins, acrylic resins,
Methacryl resin, polyacrylamide resin, polyamide resin, polyvinyl pyridine resin, cellulose resin, polyurethane resin, epoxy resin, silicone resin, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, casein, vinyl chloride-vinyl acetate copolymer, hydroxyl-modified chloride Vinyl-vinyl acetate copolymer, carboxyl-modified vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-based copolymer such as vinyl chloride-vinyl acetate-maleic anhydride copolymer, styrene-butadiene copolymer,
Examples include insulating resins such as vinylidene chloride-acrylonitrile copolymer, styrene-alkyd resin, silicon-alkyd resin, and phenol-formaldehyde resin. Further, it can be selected from organic photoconductive polymers such as poly-N-vinylcarbazole, polyvinylanthracene, and polyvinylpyrene. However, it is not limited to these insulating resins or organic photoconductive polymers. These binder resins can be used alone or in combination.
A mixture of more than one species can be used.

The dispersing solvent for dispersing the dichlorotin phthalocyanine crystal is preferably selected from those which have good solubility in the binder resin and do not dissolve the undercoat layer 4. Specific organic solvents include alcohols such as methanol, ethanol, n-propanol, i-propanol, n-butanol and benzyl alcohol, ketones such as acetone, MEK, cyclohexanone, dimethylformamide (DMF), dimethylacetamide and the like. Amides, sulfoxides such as dimethyl sulfoxide,
Cyclic or linear ethers such as dioxane, diethyl ether, methyl cellosolve and ethyl cellosolve, methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, acetic acid sec
Esters such as -butyl, tert-butyl acetate, n-amyl acetate, i-amyl acetate, methyl propionate, ethyl propionate, n-butyl propionate, ethyl butyrate, dichloromethane, chloroform, carbon tetrachloride, dichloroethylene, trichloroethylene Such as aliphatic halogenated hydrocarbons, mineral oils such as ligroin, aromatic hydrocarbons such as benzene, toluene and xylene, and aromatic halogenated hydrocarbons such as dichlorobenzene are used alone or in combination of two or more. be able to.

The compounding ratio (weight) of the dichlorotin phthalocyanine crystal to the binder resin is 40: 1 to 40: 1.
It is in the range of 1:20, preferably 10: 1 to 1:10. If the ratio of the dichlorotin phthalocyanine crystal is too high, the stability of the coating solution is reduced. On the other hand, if the ratio is too low, the sensitivity of the photoreceptor is reduced. The composition ratio (weight) of each component constituting the coating liquid is the same when the photosensitive layer has a single-layer structure described below. However, usually, 1 to 5 parts of dichlorotin phthalocyanine crystal: binder resin 1 -5 parts: dispersing solvent 40-12
A range of 0 parts is preferred. In the present invention, a condition in which the crystal form of dichlorotin phthalocyanine changes due to dispersion cannot be adopted.However, as a device for dispersing the dichlorotin phthalocyanine crystal, a ball mill, an attritor, a sand grinder mill, a dyno mill, a paint shaker And a homomixer. At this time, it is effective to reduce the particle size to 0.5 μm or less, preferably 0.2 μm or less, and most preferably 0.03 to 0.15 μm. When the primary particle size of the dichlorotin phthalocyanine crystal is less than 0.01 μm,
The stability of the crystal form in the solvent is poor, and it is easy to transfer to another crystal form. On the other hand, when the temporary particle size is larger than 0.5 μm, the electrophotography formed using it is mixed. Since the sensitivity and stability of the photoreceptor are significantly reduced, the crystal particle size is suitably in the range of 0.01 to 0.5 μm.

The coating method prepared as described above includes a coating method such as a dip coating method, a spray coating method, a spin coating method, a bead coating method, a blade coating method, a roller coating method, and a curtain coating method. Can be adopted. In addition, the drying of the coating liquid is preferably performed by touch drying at room temperature and then heating and drying at 30 to 200 ° C. for 5 minutes to 2 hours in a still or blowing condition.
The thickness of the charge generation layer 1 is usually 0.015 to 5 μm.
m, preferably 0.1 to 2.0 μm.

In the present invention, among the binder resins described above, dispersibility when dispersing dichlorotin phthalocyanine crystals in the binder resin, applicability of the dispersion and sensitivity characteristics of the photoreceptor,
It is preferable to select from at least one selected from polyvinyl acetal-based resins, vinyl chloride-vinyl acetate-based copolymers, phenoxy resins, and modified ether-type polyester resins from the viewpoints of charge retention characteristics, image quality characteristics, and the like.
In addition, among the above-mentioned dispersion solvents, not only does not change the crystal form when dispersing the dichlorotin phthalocyanine crystal in the solvent, but also has the effect of maintaining the original crystal form for a long time after the application of the dispersion. It is preferable to select a certain acetate-based solvent. In particular, a coating liquid in which dichlorotin phthalocyanine crystals are dispersed in a binder resin solution containing these binder resin and a dispersing solvent is most preferable.

In the electrophotographic photoreceptor of the present invention, when the photosensitive layer has a laminated structure, the charge transporting material 2 is coated on the charge generating material 1 by incorporating the charge transporting material into an appropriate binder resin. . As the charge transport material, 2,5-bis- (p-
Oxadiazole derivatives such as diethylaminophenyl) -1,3,4-oxadiazole, 1,3,5-triphenylpyrazoline, 1- [pyridyl- (2)]-3-
Pyrazoline derivatives such as (p-diethylaminostyryl) -5- (p-diethylaminophenyl) pyrazoline; aromatic tertiary monoamino compounds such as triphenylamine and dibenzylaniline; N, N'-diphenyl-N, N '
Aromatic tertiary diamino compounds such as -bis- (m-tolyl) benzidine; 3- (p-diethylaminophenyl)-
5,6-di- (p-methoxyphenyl) -1,2,4-
1,2,4-triazine derivatives such as triazine, hydrazone derivatives such as 4-diethylaminobenzaldehyde 2,2-diphenylhydrazone, quinazoline derivatives such as 2-phenyl-4-styrylquinazoline, 6-hydroxy-
Benzofuran derivatives such as 2,3-di- (p-methoxyphenyl) benzofuran, α-stilbene derivatives such as p- (2,2-diphenylvinyl) -N, N-diphenylaniline, triphenylmethane derivatives, Journal
of Imaging Science, 29, 7-1
0 (1985), carbazole, N-ethylcarbazole, poly-N-vinylcarbazole, halogenated poly-N-vinylcarbazole, polyglycidylcarbazole, poly-γ-carbazoleethylglutamate and derivatives thereof, Moreover,
Polycyclic aromatic compounds such as anthracene, pyrene and phenanthrene, nitrogen-containing heterocyclic compounds such as indole and imidazole, polyvinylanthracene, poly-9-vinylphenylanthracene, polyvinylpyrene, polyvinylacridine, polyvinylacenaphthylene and pyrene-formaldehyde resin A known charge transport material such as ethyl carbazole-formaldehyde resin can be used,
It is not limited to these. These charge transporting materials may be used alone or as a mixture of two or more types. When the charge transporting material is a polymer, a layer may be formed by itself.

The binder resin forming the charge transport layer 2 includes polycarbonate resin, polyester resin, methacrylic resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl acetate resin, polyvinyl butyral, and the like. Vinyl chloride-vinyl acetate copolymers such as polyvinyl acetal resin, styrene-butadiene copolymer, vinylidene chloride-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic anhydride copolymer The charge generation layer 1 such as a polymer, silicone resin, silicone-alkyd resin, phenol-formaldehyde resin, styrene-alkyd resin, poly-N-vinylcarbazole resin, etc.
The same resins as those used in the above can be used. The charge transporting layer 2 is prepared by using the same charge transporting material and binder resin and the same organic solvent as that used for forming the charge generating layer 1 to prepare a coating solution. Can be formed by applying a coating liquid. At that time, the mixing ratio (weight) of the charge transporting material and the binder resin is preferably from 10: 1 to 1: 5. The thickness of the charge transport layer 2 is generally about 5 to 50 μm, preferably 10 to 30 μm.

When the photosensitive layer of the present invention has a single-layer structure, the photosensitive layer comprises a photoconductive layer in which a dichlorotin phthalocyanine crystal and a charge transport material are dispersed in a binder resin. The same charge transporting material, binder resin and dispersion solvent as described above are used, and the photoconductive layer is formed according to the same method as described above. In this case, for the same reason as described above, the binder resin is at least one selected from a polyvinyl acetal resin, a vinyl chloride-vinyl acetate copolymer, a phenoxy resin and a modified ether polyester resin.
It is most preferable to select from the species, and it is preferable to select an acetate-based solvent as the dispersion solvent. The compounding ratio (weight) of the dichlorotin phthalocyanine crystal to the charge transporting material is 1:10 to 10: 1, and the compounding ratio (weight) of the charge transporting material to the binder resin is about 1:20 to 5: 1. It is appropriate to set.

As the conductive support 3, any one can be used as long as it can be used as an electrophotographic photosensitive member. Specifically, aluminum,
Metals such as nickel, chromium, stainless steel, aluminum, titanium, nickel, chromium, stainless steel,
Examples include a plastic film coated with a thin film of gold, vanadium, tin oxide, indium oxide, ITO, or the like, or a paper or plastic film coated or impregnated with a conductivity imparting agent. These conductive supports 3
It is used as an appropriate shape such as a drum shape, a sheet shape, and a plate shape, but is not limited thereto. Further, if necessary, the surface of the conductive support 3 may be subjected to various treatments within a range that does not affect the image quality. For example, the surface may be subjected to an oxidation treatment, a chemical treatment, a coloring treatment, or a irregular reflection treatment such as graining. And so on.

In the present invention, an undercoat layer 4 may be further interposed between the conductive support 3 and the photosensitive layer. The undercoat layer 4 prevents charge injection from the conductive support 3 into the photosensitive layer during charging of the photosensitive layer having a laminated structure, and also holds the photosensitive layer integrally adhered to the conductive support 3. The conductive support 3 has a function as an adhesive layer to be formed, or, in some cases, a function of preventing the conductive support 3 from reflecting light. The above-mentioned undercoat layer 4
As a material for forming, polyethylene resin, polypropylene resin, acrylic resin, methacrylic resin, polyamide resin, vinyl chloride resin, vinyl acetate resin, phenol resin, polycarbonate resin, polyurethane resin, polyimide resin, vinylidene chloride resin, polyvinyl acetal resin, Vinyl chloride-vinyl acetate copolymer, polyvinyl alcohol resin, polyacrylic acid resin, polyacrylamide resin, polyvinylpyrrolidone resin, polyvinylpyridine resin, water-soluble polyester resin, cellulose ester resin such as nitrocellulose, cellulose ether resin, casein, gelatin Organic zirconium compounds such as polyglutamic acid, starch, starch thiacetate, amino starch, zirconium chelate compound, titanyl chelate compound, titanyl Kokishido compound such as an organic titanyl compound of a silane coupling agent can be used. The coating method employed when forming the undercoat layer 4 includes a blade coating method, a spin coating method,
Conventional methods such as spray coating, dip coating, bead coating, roller coating, curtain coating and the like can be mentioned. The thickness of the undercoat layer 4 is 0.01 to 10 μm, preferably 0.05 to 2 μm.
μm is appropriate.

In the present invention, if necessary, the surface of the photosensitive layer may be coated with a protective layer 5. The protective layer 5 is coated so as to prevent the charge transport layer 2 from being chemically deteriorated when the photosensitive layer having a laminated structure is charged and to improve the mechanical strength of the photosensitive layer. The protective layer 5 contains a conductive material in a suitable binder resin. As a conductive material,
Metallocene compounds such as dimethylferrocene, N, N'-
Aromatic amino compounds such as diphenyl-N, N'-bis- (m-tolyl) benzidine; metal oxides such as antimony oxide, tin oxide, titanium oxide, indium oxide, and tin oxide-antimony oxide can be used. However, the present invention is not limited to these. The binder resin used for the protective layer 5 includes polyamide resin, polyurethane resin, polyester resin, epoxy resin, polyketone resin, polycarbonate resin, polyvinylketone resin,
Known resins such as polystyrene resin and polyacrylamide resin can be used. The protective layer 5 is preferably configured so that its electric resistance is 10 ⁹ to 10 ¹⁴ Ω · cm. If the electric resistance is higher than 10 ¹⁴ Ω · cm, the residual potential rises, resulting in a fogged copy,
On the other hand, when it is lower than 10 ⁹ Ω · cm, blurring of an image and reduction in resolution occur. In addition, the protective layer must be configured so as not to substantially hinder the transmission of light applied to image exposure. The coating method employed when forming the protective layer 5 includes a blade coating method, a spin coating method, a spray coating method, a dip coating method,
Conventional methods such as a bead coating method, a roller coating method, and a curtain coating method can be used. The thickness of the protective layer 5 is suitably 0.5 to 20 μm, preferably 1 to 10 μm.

[0023]

The present invention will be specifically described below with reference to examples. In Examples and Comparative Examples, “parts” means parts by weight. Synthesis Example 1 50 g of phthalonitrile and 27 g of anhydrous stannic chloride were added to 350 ml of 1-chloronaphthalene, and 195 ° was added.
After reacting at C for 5 hours, the product was filtered off. 1
-Washed with chlornaphthalene, acetone, methanol and water, dried under reduced pressure and dried to obtain dichlorotin phthalocyanine crystal 1
8.3 g (27%) were obtained. FIG. 5 shows a powder X-ray diffraction pattern of the obtained dichlorotin phthalocyanine crystal.

Synthesis Example 2 64 g of phthalonitrile and 26 g of anhydrous stannous chloride were added to 70 ml of 1-chloronaphthalene.
And then cooled to 100 ° C.
100 ml of F was added and stirred for 30 minutes. Thereafter, the product was separated by filtration, washed with methanol and water, and dried under reduced pressure to obtain 79 g (90%) of dichlorotin phthalocyanine. FIG. 6 shows a powder X-ray diffraction pattern of the obtained dichlorotin phthalocyanine crystal.

Example 1 5 g of the dichlorotin phthalocyanine obtained in Synthesis Example 1 was mixed with 10 g of salt and 500 g of agate ball (20 mmφ).
Together with an agate pot (capacity: 500 ml) and 400 in a planetary ball mill (Fritsch: P-5).
Milled for 10 hours at rpm. The resulting dichlorotin phthalocyanine crystals had a uniform particle size of 0.05 to 0.08 μm. The powder X-ray diffraction pattern is shown in FIG.

Example 2 A pulverization treatment was carried out in the same manner as in Example 1 except that 5 g of dichlorotin phthalocyanine obtained in Synthesis Example 2 was used. The crystal form and particle size of the obtained dichlorotin phthalocyanine crystal were the same as in Example 1.

Example 3 0.5 g of the dichlorotin phthalocyanine crystal obtained in Example 1 was mixed with 15 ml of THF and glass beads (1 mm).
φ) After milling at room temperature for 24 hours with 30g,
The glass beads were separated by filtration and dried to obtain 0.45 g of dichlorotin phthalocyanine crystals. The resulting dichlorotin phthalocyanine crystals had a uniform particle size of 0.05 to 0.1 μm. FIG. 8 shows the powder X-ray diffraction pattern.

Example 4 A solvent treatment was carried out in the same manner as in Example 3 except that n-butyl acetate was used instead of THF. The obtained dichlorotin phthalocyanine crystals had a uniform particle size of 0.05 to 0.1 μm, and the powder X-ray diffraction pattern was the same as that in FIG.

Example 5 A pulverization treatment was performed in the same manner as in Example 1 except that no salt was used as a grinding aid. The powder X-ray diffraction pattern of the obtained dichlorotin phthalocyanine crystal was the same as that of FIG. 7, but the particle size of the crystal pulverized without using an inorganic salt was 0.1%.
Those having a size of about 0.5 μm were mixed with those having a size of from 0.5 to 0.08 μm, and were non-uniform.

Example 6 The procedure of Example 3 was repeated except that 0.5 g of the dichlorotin phthalocyanine crystal obtained in Example 5 was used.
The powder X-ray diffraction pattern of the obtained dichlorotin phthalocyanine crystal was similar to that of FIG.
It was 0.2 μm inhomogeneous.

Example 7 A pulverization treatment was performed in the same manner as in Example 1 except that the pulverization time was changed to 30 hours. The particle size of the obtained dichlorotin phthalocyanine crystal was 0.01 to 0.03 μm.
The particle size was smaller than that of the sample and was uniform. The powder X-ray diffraction pattern is shown in FIG.

Comparative Example 1 Dichlorotin phthalocyanine crystal 1 obtained in Synthesis Example 1
g of ice-cooled ice-cooled water at 0 to 5 ° C in 30 ml of concentrated sulfuric acid.
The solution was added dropwise to the resulting solution with vigorous stirring. Next, the formed precipitate was separated by filtration, washed repeatedly with water until the washing liquid became neutral, and dried under reduced pressure to obtain 0.76 g of dichlorotin phthalocyanine crystals. FIG. 10 shows an X-ray powder diffraction pattern of the obtained dichlorotin phthalocyanine crystal.

Example 8 Dichlorotin phthalocyanine crystal 1 obtained in Example 1
The mixture was mixed with 1 part of polyvinyl butyral (manufactured by Sekisui Chemical Co., Ltd .: ESLEC BM-S) and 100 parts of cyclohexanone, and treated with glass beads for 1 hour using a paint shaker to prepare a coating liquid in which the crystals were dispersed. Then
An aluminum substrate is used as a conductive support 3, and the above-mentioned coating solution is applied thereon by dip coating, and dried by heating at 100 ° C. for 5 minutes to form a charge generation layer 1 having a thickness of 0.2 μm.
Was formed.

Next, the following structural formula (1)

Embedded image N, N'-diphenyl-N, N'-bis-
(M-tolyl) benzidine 2 parts

The following structural formula (2)

Embedded image And 3 parts of poly [1,1-di- (p-phenylene) cyclohexane carbonate] represented by
And applying the obtained coating solution to the aluminum substrate on which the charge generation layer 1 is formed by dip coating.
The resultant was dried by heating at 120 ° C. for 1 hour to form a charge transport layer 2 having a thickness of 20 μm.

The electrophotographic characteristics of the thus produced electrophotographic photosensitive member were measured as follows. Using an electrostatic copying paper test apparatus (manufactured by Kawaguchi Electric Co., Ltd .: Electrostatic Analyzer EPA-8100), room temperature and normal humidity (2
After charging the photoconductor by a corona discharge of -6 KV in an environment of 0 ° C. and 40% RH), the light of the tungsten lamp is split into 800 nm monochromatic light using a monochromator, and 1 μW on the photoconductor surface. / Cm ² and irradiation. Then, the half-exposure amount E _1/2 (e) until the initial surface potential V ₀ (volts) becomes 1/2 of V _0.
rg / cm ² ), and then irradiate the surface of the photoreceptor with 10 lux of tungsten light for 1 second.
_R (volts) was measured. Furthermore, the above charge, V _0, E _1/2 after repeating 1000 times the exposure was measured V _R. The results are shown in Examples 9 to 12 and Comparative Example 2 below.
The results are shown in Table 1 below.

Examples 9 to 12 Except that the dichlorotin phthalocyanine obtained in each of Examples 3 to 6 was used, a charge generation layer 1 and a charge transport layer 2 were formed in the same manner as in Example 8, and electrophotography was performed. A photoreceptor was prepared, and the electrophotographic characteristics were evaluated by the same method.

Comparative Example 2 A charge generating layer 1 and a charge transport layer 2 were formed in the same manner as in Example 8 except that the dichlorotin phthalocyanine crystal obtained in Synthesis Example 1 was used to prepare an electrophotographic photosensitive member. And
Electrophotographic properties were evaluated in a similar manner.

Comparative Example 3 A charge generating layer 1 and a charge transporting layer 2 were formed in the same manner as in Example 8 except that the dichlorotin phthalocyanine crystal obtained in Comparative Example 1 was used to produce an electrophotographic photosensitive member. And
Electrophotographic properties were evaluated in a similar manner.

[0040]

[Table 1]

Example 13 Alcohol-soluble nylon resin (Lacamide L-5003, manufactured by Dainippon Ink and Chemicals, Inc.) on an aluminum substrate
A solution consisting of 1 part and 10 parts of methanol was applied by a dip coating method, and dried by heating at 120 ° C. for 10 minutes to form an undercoat layer 4 having a thickness of 0.5 μm. Next, 1 part of the dichlorotin phthalocyanine crystal obtained in Example 1 was replaced with a polyvinyl butyral resin (Slec B, manufactured by Sekisui Chemical Co., Ltd.).
MS) 1 part and 100 parts of n-butyl acetate,
The crystal was dispersed in a resin solution by treating with a glass shaker for 1 hour using a paint shaker. The obtained coating solution is applied onto the undercoat layer 4 by a dip coating method,
The resultant was dried by heating at 0 ° C. for 10 minutes to form a charge generation layer 1 having a thickness of 0.15 μm. It should be noted that the crystal form of the dichlorotin phthalocyanine crystal after dispersion was not changed by X-ray diffraction as compared with the crystal form before dispersion. Next, a charge transport layer 2 was formed on the charge generation layer 1 in the same manner as in Example 8.

The electrophotographic characteristics of the thus produced electrophotographic photosensitive member were measured as follows. Using an electrostatic copying paper test apparatus (manufactured by Kawaguchi Electric Co., Ltd .: Electrostatic Analyzer EPA-8100), a normal temperature and normal humidity (20
After charging the photoreceptor by a corona discharge of −6 KV in an environment of 40 ° C., 40% RH), the light of a tungsten lamp is
The light was split into monochromatic light of 800 nm using a monochromator, adjusted to 1 μW / cm ² on the surface of the photoreceptor, and irradiated. Then, the initial surface potential V _O (volt) and the half-life exposure amount E _1/2 (erg / cm ² ) were measured.
Thereafter, the surface of the photoreceptor was irradiated with 10 lux of white light for 1 second, and the residual potential V _R (volt) was measured. Furthermore, V _O after repeating the above charging and exposure 1000 times,
E _1/2, was measured V _R. The dichlorotin phthalocyanine crystal constituting the charge generation layer 1 and the binder resin and the measurement results described above were used in Examples 14 to 19 and Comparative Examples 4 to 7 below.
The results are shown in Table 2 below.

Example 14 A polyester resin (manufactured by Toyobo: Viron 2) was used in place of the polyvinyl butyral resin constituting the charge generation layer 1.
00) A photoconductor was prepared in the same manner as in Example 13 except that 1 part was used, and the same measurement was performed.

Comparative Example 4 A photoconductor was prepared in the same manner as in Example 13, except that the dichlorotin phthalocyanine crystal obtained in Synthesis Example 1 was used instead of the dichlorotin phthalocyanine crystal obtained in Example 1, Was measured.

Comparative Example 5 A photoconductor was prepared in the same manner as in Example 13, except that the dichlorotin phthalocyanine crystal obtained in Comparative Example 1 was used instead of the dichlorotin phthalocyanine crystal obtained in Example 1. Was measured.

Example 15 A solution consisting of 1 part of an alcohol-soluble nylon resin (manufactured by Toray Industries, Ltd .: CM-8000) and 10 parts of methanol was applied on an aluminum substrate by dip coating at 110 ° C.
For 10 minutes to form an undercoat layer 4 having a thickness of 0.1 μm. Next, 1 part of the dichlorotin phthalocyanine crystal obtained in Example 3 was partially formalized to a polyvinyl butyral resin (manufactured by Sekisui Chemical: Eslec BX-
2) 1 part and 100 parts of cyclohexanone were mixed, and treated with a glass shaker for 1 hour using a paint shaker to disperse the crystals in the resin solution. The obtained coating solution is applied on the undercoat layer 4 by a dip coating method,
The resultant was dried by heating at 10 ° C. for 10 minutes to form a charge generation layer 1 having a thickness of 0.2 μm. It should be noted that the crystal form of the dichlorotin phthalocyanine crystal after dispersion was not changed by X-ray diffraction as compared with the crystal form before dispersion.

Then, N, represented by the structural formula (1),
Instead of N'-diphenyl-N, N'-bis- (m-tolyl) benzidine, the following structural formula (3)

Embedded image N, N'-bis- (p-tolyl) -N, N '
A charge transport layer 2 was formed in the same manner as in Example 13 except that 2 parts of -bis- (p-ethylphenyl) -3,3'-dimethylbenzidine was used.
The same measurement as in Example 3 was performed.

Example 16 The same procedure as in Example 15 was carried out except that 1 part of a polymethyl methacrylate resin (manufactured by DuPont: Elvacite 2021) was used in place of the partially formalized polyvinyl butyral resin constituting the charge generation layer 1. A photoconductor was prepared, and the same measurement as in Example 13 was performed.

Comparative Example 6 A photoconductor was prepared in the same manner as in Example 15, except that the dichlorotin phthalocyanine crystal obtained in Comparative Example 1 was used instead of the dichlorotin phthalocyanine crystal obtained in Example 3. The same measurement as in Example 13 was performed.

Example 17 A solution comprising 10 parts of a zirconium compound (manufactured by Matsumoto Pharmaceutical Co., Ltd .: Organix ZC540), 1 part of a silane compound (manufactured by Japan Junker Co., Ltd .: A1110), 40 parts of i-propanol and 20 parts of butanol was placed on an aluminum substrate. At 160 ° C. by dip coating.
By heating and drying for 0 minutes, an undercoat layer 4 having a thickness of 0.1 μm was formed. Next, 1 part of the dichlorotin phthalocyanine crystal obtained in Example 4 was combined with 1 part of a vinyl chloride-vinyl acetate copolymer (manufactured by Union Carbide: VMCH) and n-acetate acetate.
The crystals were mixed with 100 parts of butyl and treated with a glass shaker for 1 hour on a paint shaker to disperse the crystals in the copolymer solution. The obtained coating solution was applied on the undercoat layer 4 by a dip coating method, and dried by heating at 100 ° C. for 10 minutes to form a charge generation layer 1 having a thickness of 0.2 μm.
It should be noted that the crystal form of the dichlorotin phthalocyanine crystal after dispersion was not changed by X-ray diffraction as compared with the crystal form before dispersion. Then, the same charge transport layer 2 as in Example 15 was formed, and the same measurement as in Example 13 was performed on the manufactured photoreceptor.

Example 18 Example 17 was repeated except that 1 part of a phenoxy resin (manufactured by Union Carbide: PKHH) and 100 parts of cyclohexanone were used instead of the vinyl chloride-vinyl acetate copolymer constituting the charge generating layer 1. The same photoreceptor was prepared and the same measurement was performed.

Example 19 Instead of the vinyl chloride-vinyl acetate copolymer constituting the charge generating layer 1, 1 part of a modified ether type polyester resin (STAFIX NLC-2, manufactured by Fuji Photo Film Co., Ltd.) and 100 parts of cyclohexanone were used. Example 1 except for
A photoreceptor similar to that of Example 7 was produced, and the same measurement was performed.

Comparative Example 7 A photoconductor was prepared in the same manner as in Example 17, except that the dichlorotin phthalocyanine crystal obtained in Comparative Example 1 was used instead of the dichlorotin phthalocyanine crystal obtained in Example 4, Was measured.

[0054]

[Table 2]

Examples 20 to 24 A drum type photoreceptor was manufactured under the same conditions as in Examples 13, 15, 17 to 19, and this electrophotographic photoreceptor was mounted on a semiconductor laser printer (Fuji Xerox: FX XP-1).
5), a copied image was formed, and copying was repeated 10,000 times. The results are shown in Table 3 below.

Comparative Examples 8 to 10 A drum-type photosensitive member was manufactured under the same conditions as Comparative Examples 5 to 7,
The same evaluation as in Example 20 was performed. Table 3 shows the results.

[0057]

[Table 3]

Comparative Example 11 A coating solution for a photoreceptor was prepared in the same manner as in Example 13 except that THF was used as the dispersion solvent. Then, when the crystal form of the dichlorotin phthalocyanine crystal after dispersion was confirmed by X-ray diffraction, it was found that the crystal form had changed compared to the crystal form before dispersion. FIG. 12 shows an X-ray diffraction diagram of the coating solution in which the dichlorotin phthalocyanine crystals are dispersed. Next, an electrophotographic photosensitive member was prepared in the same manner as in Example 13, and the electrophotographic characteristics were measured in the same manner. Table 4 shows the results. FIG. 1 shows the absorption spectrum of this electrophotographic photosensitive member.
It is shown in FIG.

Comparative Example 12 Example 13 was repeated except that chlorobenzene was used as the dispersing solvent.
A coating solution for a photoreceptor was prepared in the same manner as described above. Then, the crystal form of the dichlorotin phthalocyanine crystal after dispersion is changed to X
When confirmed by line diffraction, it was found to be different from the crystal form before dispersion. FIG. 1 shows an X-ray diffraction diagram of the coating solution in which the dichlorotin phthalocyanine crystal was dispersed.
3 is shown. Next, an electrophotographic photosensitive member was prepared in the same manner as in Example 13, and the electrophotographic characteristics were measured in the same manner. Table 4 shows the results.

[0060]

[Table 4]

[0061]

According to the present invention, dichlorotin phthalocyanine synthesized by a known method is resistant to a specific Bragg angle by a simple treatment of mechanically pulverizing it with an inorganic salt or further treating it with a solvent. New crystals of dichlorotin phthalocyanine having a diffraction peak can be produced. This novel crystal is very useful as a charge generation material for an electrophotographic photoreceptor such as a printer using a semiconductor laser because the photosensitive wavelength range extends to a long wavelength. Further, the electrophotographic photoreceptor of the present invention produced using the above-mentioned dichlorotin phthalocyanine crystal has high durability, low residual potential, high chargeability, and little variation due to repeated copying operations, Is excellent. Moreover, an electrophotographic photosensitive member containing a dichlorotin phthalocyanine crystal as a charge generating material and a polyvinyl acetal-based resin or a vinyl chloride-vinyl acetate-based copolymer as a binder resin in the photosensitive layer has higher sensitivity and has higher charge retention. It has excellent properties and has few image quality defects, and thus has remarkably excellent image quality characteristics .

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of an electrophotographic photosensitive member according to the present invention.

FIG. 2 shows another schematic sectional view of the electrophotographic photosensitive member according to the present invention.

FIG. 3 shows another schematic cross-sectional view of the electrophotographic photosensitive member according to the present invention.

FIG. 4 shows still another schematic cross-sectional view of the electrophotographic photosensitive member according to the present invention.

5 shows a powder X-ray diffraction pattern of the dichlorotin phthalocyanine crystal obtained in Synthesis Example 1. FIG.

6 shows a powder X-ray diffraction pattern of the dichlorotin phthalocyanine crystal obtained in Synthesis Example 2. FIG.

7 shows a powder X-ray diffraction pattern of the dichlorotin phthalocyanine crystal obtained in Example 1. FIG.

8 shows a powder X-ray diffraction pattern of the dichlorotin phthalocyanine crystal obtained in Example 3. FIG.

9 shows a powder X-ray diffraction pattern of the dichlorotin phthalocyanine crystal obtained in Example 7. FIG.

10 shows a powder X-ray diffraction pattern of the dichlorotin phthalocyanine crystal obtained in Comparative Example 1. FIG.

11 shows an absorption spectrum of the electrophotographic photoreceptor produced in Comparative Example 11. FIG.

FIG. 12 shows an X-ray diffraction diagram of a coating solution for a photoreceptor prepared in Comparative Example 11.

13 shows an X-ray diffraction diagram of a coating solution for a photoreceptor prepared in Comparative Example 12. FIG.

[Explanation of symbols]

1) charge generation layer, 2) charge transport layer, 3) conductive support, 4) undercoat layer, 5) protective layer.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masakazu Iijima 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Inside the Fujimatsu Rocks Co., Ltd. In-house (72) Inventor Seiwa Mashita 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Fuji Xerox Co., Ltd. Takematsu Office (56) References JP-A-62-127843 (JP, A) JP-A-3-61952 (JP, A) JP-A-3-174543 (JP, A) JP-A-2-97959 (JP, A) JP-A-1-133790 (JP, A) JP-A-3-73961 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C09B 67/50

Claims (7)

(57) [Claims] 1. In an X-ray diffraction spectrum, a Bragg angle (2θ ± 0.2 °) is 8.5 °, 11.2 °, and 14.
A dichlorotin phthalocyanine crystal having strong diffraction peaks at 5 ° and 27.2 °. 2. The method for producing a dichlorotin phthalocyanine crystal according to claim 1, wherein the dichlorotin phthalocyanine is mechanically pulverized together with an inorganic salt or is pulverized and then subjected to a solvent treatment. 3. An electrophotographic photosensitive member comprising a photosensitive layer containing the dichlorotin phthalocyanine crystal according to claim 1 coated on a conductive support. 4. The photosensitive layer according to claim 3, wherein the binder resin contains at least one selected from a polyvinyl acetal resin, a vinyl chloride-vinyl acetate copolymer, a phenoxy resin and a modified ether type polyester resin. The electrophotographic photosensitive member according to the above. 5. The electrophotographic photoreceptor according to claim 4, wherein the polyvinyl acetal-based resin comprises one or more selected from a polyvinyl butyral resin, a polyvinyl formal resin and a partially acetalized polyvinyl butyral resin. 6. The vinyl chloride-vinyl acetate copolymer is one selected from a vinyl chloride-vinyl acetate copolymer, a hydroxyl-modified vinyl chloride-vinyl acetate copolymer and a carboxyl-modified vinyl chloride-vinyl acetate copolymer. 5. The electrophotographic photoreceptor according to claim 4, comprising at least two types. 7. The charge generating layer according to claim 4, wherein the photosensitive layer has a laminated structure in which a charge generating layer and a charge transporting layer are sequentially laminated, and a dichlorotin phthalocyanine crystal and a binder resin are contained in the charge generating layer. The electrophotographic photosensitive member according to the above.