KR100653027B1 - Novel metal-free phthalocyanine and electrophotographic photoreceptor drum using the same - Google Patents

Abstract

The present invention is prepared by thermally converting beta-type or X-type metal-free phthalocyanine at 50 to 200 ° C. for 1 to 200 hours and having 2θ (bragg angle: ± 0.2 degrees) at X-ray diffraction peaks of 7.3, 8.8, 16.4, 17.1, and 20.0. Charge generation by using a coating solution composed of a new crystalline metal-free phthalocyanine and a new crystalline metal-free phthalocyanine such as 20.5, 21.2, 21.9, 23.6, 27.1, 28.3, and 30.1 as a charge generating material and a binder resin and a solvent added thereto. A layer is formed, and the charge transfer layer is formed using a coating liquid composed of two or more types of charge transfer materials, binder resins, charge manipulators, antioxidants, and solvents. An electrophotographic photosensitive drum comprising a charge transfer layer or a conductive substrate / charge generation layer / charge transfer layer is provided, which has excellent photosensitivity and dark attenuation characteristics. Metal-free phthalocyanine of the electrophotographic photosensitive drum of the present invention using a suitable and has the advantage that an excellent resolution of the printed image where requiring fast printing speed.

Metal-free phthalocyanine, thermal conversion, electrophotographic photosensitive drums, charge generating materials, charge transfer materials,

Description

Novel metal-free phthalocyanine and electrophotographic photosensitive drum using the same {{NOVEL METAL-FREE PHTHALOCYANINE AND ELECTROPHOTOGRAPHIC PHOTORECEPTOR DRUM USING THE SAME}             

The present invention relates to a novel metal-free phthalocyanine and an electrophotographic photosensitive drum having excellent sensitivity and attenuation using the same as a charge generating material of the charge generating layer.

Electrophotographic photoreceptor drums used in laser printers, copiers, and facsimile machines are an important part of forming electrostatic afterimages on the drum surface by optical signals and expressing characters and images by toners. The photosensitive drum is composed of several thin layers and is generally composed of an insulating layer (Block Layer), a charge generation layer (Charge Generation Layer), a charge transport layer (Charge Transport Layer). As the insulating layer, a metal oxide film or an insulating polymer is used, and the charge generating layer is coated with a charge generating material of an inorganic pigment or an organic pigment and a binder resin together or applied by vacuum deposition. The charge transfer layer coats the charge transfer material and the binder resin together on the charge generation layer. In some cases, there may be only a charge generating layer and a charge transfer layer, or a single charge generation layer and a charge transfer layer, and a charge generation layer may be applied on the charge transfer layer to protect the charge generation layer. In order to apply a protective layer. In particular, the charge generating layer is an important material in which the charge generating material generates charges by signals generated by light to form afterimages of data. The charge generating layer can easily change the electrostatic properties of an electrophotographic photosensitive drum and can be manufactured according to the synthesis of pigments used. Organic pigments are in the spotlight due to the advantage of being able to produce drums of character.

The electrophotographic photosensitive drum is specifically used in accordance with the type and characteristics of the organic pigment used in the charge generating layer. Generally, azo (Azo), perylene (Perylene), phthalocyanine (Phthalocyanine) pigments, etc. are used, the pigment used depending on the laser printer, copier and light source of the facsimile. 632 nm light for printers using helium-neon lasers, 650 nm light for light emitting diodes (LEDs), 700 to 800 nm for gallium-aluminum lasers In order to irradiate the light from, it is necessary to use pigments suitable for these areas. Recently, due to the damage and danger of drums caused by short wavelength light, many light sources near the IR (Infra Red) area are used. Although phthalocyanine is commonly used as a charge generating material, which has excellent heat resistance, chemical resistance, light resistance, and excellent photoconductivity by light, it exhibits different electrostatic properties according to its crystal form and type. Selective preparation of the crystalline form is of great importance.

The charge generating materials used in the charge generating layer include copper phthalocyanine, titanium oxide phthalocyanine, vanadium oxide phthalocyanine, and indium chloride phthalocyanine, in which a metal is substituted at the center of the phthalocyanine. Alkali or combinations of metal phthalocyanine, metal phthalocyanine and metal-free or metal phthalocyanine derivatives such as chloride phthalocyanine, hydroxygallium phthalocyanine, and tin oxide phthalocyanine are used, but various crystal structures are used. In addition, since the electrostatic properties vary depending on the crystal structure, its use has also been limited. In general, metal-substituted phthalocyanine pigments have excellent sensitivity characteristics compared to metal-free phthalocyanine pigments, but have a disadvantage of being very expensive.

Patent No. 3,357,987 (1967) for a method of manufacturing an electrophotographic photosensitive drum using X (χ) type metal free phthalocyanine as a crystalline form suitable for use among metal free phthalocyanines is disclosed in US Patent No. 3,357,987 (1967) and tau (τ) type metal free phthalocyanine. A patent relating to the manufacturing method of the electrophotographic photosensitive drum used was disclosed in Japanese Patent No. 5813757 (1983). However, metal-free phthalocyanine has the disadvantages of low sensitivity and poor darkening compared to titanium oxide phthalocyanine, which is a metal phthalocyanine. X-type metal-free phthalocyanine pigments have a lower sensitivity to light and darker than tau-type metal-free phthalocyanine pigments. The disadvantage is low attenuation. These crystal forms are diffraction peaks of powder XRD (X-Ray Diffratometer), which can be seen as 2θ (Bragg angle: degree) value in Cu-K alpha light source. In other words, the X-type metal-free phthalocyanine pigments have important peaks at 2θ values of 7.5, 9.1, 16.7, 17.3, 22.3, and 28.5, while the tau type metal-free phthalocyanine pigments are 7.6, 9.2, 16.8, 17.4, 20.4, 20.9, 21.5, Important peaks appear at 27.5 and 29.4.

In sum, the metal-substituted phthalocyanine, which has been conventionally used as a charge generating material, has excellent sensitivity characteristics, but it is expensive and difficult to use commercially. The metal-free phthalocyanine has a defect in low sensitivity and good darkening depending on the crystalline form.

An object of the present invention is to overcome the problems of the prior art described above, and to replace the conventional metal-substituted phthalocyanine, while using a novel metal-free phthalocyanine having excellent photosensitivity and darkening properties, and using it as a charge generating material of the charge generating layer. It is to provide an electrophotographic photosensitive drum.

That is, one aspect of the present invention is prepared by thermally converting beta-type or X-type metal-free phthalocyanine at 50 to 200 ° C. for 1 to 200 hours and having 2θ (bragg angle: ± 0.2 degrees) at X-ray diffraction peaks of 7.3 and 8.8. , 16.4, 17.1, 20.0, 20.5, 21.2, 21.9, 23.6, 27.1, 28.3, 30.1 to provide a new crystalline metal-free phthalocyanine.

Another aspect of the invention is an electrophotographic photosensitive drum comprising a conductive substrate / insulation layer / charge generation layer / charge transfer layer or conductive substrate / charge generation layer / charge transfer layer, wherein the charge generation layer is described above. It is formed by using a coating solution formed by adding crystalline metal-free phthalocyanine as a charge generating material and adding a binder resin and a solvent. The charge transfer layer is formed of two or more types of charge transfer materials, binder resins, charge labor materials, antioxidants, and solvents. An electrophotographic photosensitive drum is formed using a composition coating composition.

Hereinafter, the present invention will be described in detail.

The novel new metal-free phthalocyanine of the present invention is prepared by thermal conversion at 50-200 ° C. for 1-200 hours using beta-type metal-free phthalocyanine or X-type metal-free phthalocyanine. Such thermal conversion treatment is preferably carried out by adding a solvent to the metal-free phthalocyanine, and then adding a binder resin and an additional solvent, milling it into a dispersion state, and adding the solvent to the dilution and sonication again to stabilize it. It is important to make the coating liquid. The thermally transformed metal-free phthalocyanine of the present invention has photosensitivity with peaks at 2θ (± 0.2 degrees) in XRD of 7.3, 8.8, 16.4, 17.1, 20.0, 20.5, 21.2, 21.9, 23.6, 27.1, 28.3, and 30.1. Excellent metal-free phthalocyanine with high attenuation. In this case, a metal-free phthalocyanine derivative having one or more substituents in the phthalocyanine molecule may be mixed in a weight ratio of 1: 0.05 to 1: 5, and preferred substituents include amino, nitro, cyano, alkyl, alkoxy and mercury groups. Lecapto group, halogen group, sulfone group, carboxyl group, metal salt of carboxyl group, ammonium group, amine salt, alkylene group, sulfonyl group, carbonyl group, imino group and the like.

Another aspect of the invention is an electrophotographic photosensitive drum suitable for gallium-aluminum-arsonide lasers (700-800 nm). In the present invention, the electrophotographic photosensitive drum is not particularly limited, but it is preferable to use an aluminum drum, and the surface of the electrophotographic photosensitive drum may be used as it is, or the metal oxide film may not be used as it is, or a metal oxide film, Al ₂ O ₃ or ITO (Indium Titanium Oxide) Unused drum is used by coating an insulating layer (Block Layer).

The electrophotographic photosensitive drum of the present invention is composed of a conductive substrate / insulating layer / charge generating layer / charge transfer layer or conductive substrate / charge generating layer / charge transfer layer. In the electrophotographic photosensitive drum of the present invention, the insulating layer is formed of a coating liquid consisting of polyamide and a solvent. A coating liquid in which 1 to 10% by weight of polyamide is dissolved in 90 to 99% by weight of alcohol is settled in an aluminum drum (30 mmψ × 243 mm). Coating. At this time, the thickness of the appropriate insulating layer is 0.3 to 2 micrometers and the coated drum is dried for 0.1 to 3 hours at 50 to 200 ℃ to prepare for the next step, the charge generation layer coating.

In the present invention, the charge generating layer is formed of a coating liquid mainly composed of a charge generating material, a binder resin, and a solvent, and as the charge generating material, the novel metal-free phthalocyanine of the present invention described above is used.

The preferred composition of the stabilized coating solution for the formation of the charge generating layer in the present invention is 2 to 40% by weight of metal-free phthalocyanine, 1 to 55% by weight of the binder resin, and 5 to 97% by weight of the solvent. An additive such as a substance may be included. As described above, the method for preparing the coating solution is to add about 1/4 of the total amount of the solvent (5 to 97% by weight) to the total amount of metal-free phthalocyanine (2 to 40% by weight) as described above at 1 to 200 hours at 50 to 200 ° C. After the heat conversion treatment, the total amount of binder resin (1 to 55% by weight) and 1/4 of the total amount of the solvent are added thereto, followed by milling to form a dispersion. The remaining 2/4 amount of the solvent is added thereto, followed by ultrasonic treatment to stabilize the coating solution. Get In this case, the milling may use mechanical methods such as kneader, banbury mixer, attritor, roll mill, ball mill, sand mill, SPEX mill, homogenizer, jaw crusher, stamp mill, cutter mill, dyno mill, micronizer, paint shaker, A high speed stirrer, a microfluidizer, an optimizer, an ultrasonic grinder, etc. can be used.

In the present invention, as the binder resin, polyvinyl butyl al resin, polyvinyl alcohol resin, polyamide resin, polyvinylacetate resin, polyvinyl chloride resin, polyacrylic resin, polyurethane resin, polycarbonate resin, polymethacrylic resin, Polyvinylidene chloride resin, polystyrene resin, styrene-butadiene copolymer resin, styrene-methacrylic acid methyl resin, vinylidene chloride-acrylonitrile copolymer resin, vinyl chloride-vinylacetate copolymer resin, vinyl chloride-vinyl Acetate-maleic anhydride copolymer resin, ethylene-acrylic acid copolymer resin, ethylene-vinylacetate copolymer resin, methylcellulose, nitrocellulose, polysilicon resin, silicone-alkyd resin, phenol-formaldehyde resin, cresol-formaldehyde resin, Styrene-alkyd resins, poly-N-vinylcarbazole resins, poly Vinylformal resin, polyhydroxystyrene resin, polynorbornyl resin, polycycloolefin resin, polyvinylpyrrolidone resin, poly (2-ethyl-2-oxazoline) resin, melamine resin, urea resin, amino resin, Isocyanate resin, an epoxy resin, etc. are mentioned, These can be used individually or in combination of 2 or more types. Among these, a particularly preferable example is one in which a polyvinylbutylal resin and a styrene-acrylic resin are mixed in a weight ratio of 1: 0.1 to 1:10. The amount of resin used may be 1 to 200% by weight relative to the charge generating material, and more preferably 10 to 100% by weight. If it is less than 10% by weight, it is difficult to form a uniform charge generating layer, and the adhesive strength with the substrate is also weakened, and it is difficult to maintain the charge potential at more than 100% by weight.

In the present invention, the solvent is methyl isopropyl ketone, methyl isobutyl ketone, 4-methoxy-4-methyl-2-pentanone, isopropyl acetate, isobutyl acetate, tertiary butyl acetate, isopropyl alcohol, isobutyl alcohol , Acetone, methyl ethyl ketone, cyclohexanone, 1,2-dichloroethane, 1,2-dichloropropane, 1,1,2-trichloroethane, 1,1,1-trichloroethane, trichloroethylene, Tetrachloroethane, dichloromethane, tetrahydrofuran, dioxane, methanol, ethanol, 1-propanol, 1-butanol, 2-butanol, 1-methoxy-2-propanol, ethyl acetate, butyl acetate, dimethyl sulfoxide, methyl Cellosolve, butylamine, diethylamine, ethylenediamine, isopropanolamine, triethanolamine, triethylenediamine, N, N'-dimethylformamide, benzene, toluene, xylene, methylbenzene, ethylbenzene, cyclohexane And these alone or two It is used in combination, and at least amount is 5-97%, based on the weight of the coating solution.

In more detail describing the production of the charge generating layer in the present invention, glass beads, steel beads, zirconia beads, 2-40% by weight of specially prepared metal-free phthalocyanine, 1-55% by weight of binder resin, and 5-97% by weight of solvent, Alumina beads, zirconia balls or steel balls are added and dispersed for 2 to 20 hours using a disperser. As a disperser that can be used, a high speed stirrer, a paint shaker, a ball mill, a sand mill, a dyno mill, a two roll mill, a three roll mill, an ultrasonic grinder, a microfluidizer, an optimizer, etc. may be used. The charge generating layer coating solution thus prepared is uniformly coated on an aluminum drum using a spin coater, bar coater, doctor blade, roller coater, curtain coater, bead coater, and sedimentation coater, and then dried at 50 to 200 ° C. for 0.1 to 4 hours. Let's do it. At this time, the thickness of the charge generation layer is 0.01 to 3 micrometers. The coaters can also be used to coat insulating and charge transfer layers.

In the present invention, the charge transfer layer includes a charge transfer material (3-30 wt%), a binder resin (5-50 wt%), a charge attraction material (0.01-5 wt%), an antioxidant (0.01-5 wt%) and a solvent (10 to 91.8 weight percent). In addition, the charge transfer material may be used in combination of two or more, hydrazone-based and butadiene-based may be used by mixing 1: 0.1 to 1: 5 by weight ratio. Charge transfer material usable in the present invention serves to transfer the charge generated in the charge generating layer to the drum surface, 1,1-bis- (para-diethylaminophenyl) -4-, 4-diphenyl- 1,3-butadiene, N, N'-bis (olso, para-dimethylphenyl) -N, N'-diphenylbenzidine, 3,3'-dimethyl-N, N, N ', N'-tetrakis- 4-methylphenyl- (1,1'-biphenyl) -4,4'-diamine, N-ethyl-3-carbozolylaldehyde-N, N'-diphenylhydrazone, 4- (N, N-bis ( Para-toluyl) amino) -betaphenylstilbene, N, N, N ', N'-tetrakis (3-methylphenyl) -1,3-diaminobenzene, N, N-diethylaminobenzaldehydediphenyl- Hydrazone, N, N-dimethylaminobenzaldehydediphenyl-hydrazone, 4-dibenzylamino-2-methylbenzaldehydediphenylhydrazone, 2,5-bis (4-aminophenyl)-[1,3,4] Oxadiazole, (2-phenylbenzo [5,6-b] -4H-thiopyran-4ylidene) -propanedinitrile-1,1-dioxide, 4-bromo-triphenylamine, 4,4 ' -(1,2-ethanediily ) -Bis (2,6-dimethyl-2,5-cyclohexadien-1-one), 3,4,5, -triphenyl-1,2,4-triazole, 2- (4-methylphenyl)- 6-phenyl-4H-thiopyran-4-ylidene] -propanedinitrile-1,1-dioxide, 4-dimethylamino-benzaldehyde-N, N-diphenylhydrazone, 9-ethylcarbazole-3-aldehyde -N-methyl-N-phenylhydrazone, 5- (2-chlorophenyl) 3- [2- (2-chlorophenyl) ethenyl] -1-phenyl-4,5-dihydro-1H-pyrazole, 4-diethylamino-benzaldehyde-N, N-diphenylhydrazone, N-biphenylyl-N-phenyl-N- (3-methylphenyl) amine, 9-ethylcarbazole-3-aldehyde -N, N- Diphenylhydrazone, 3,5-bis (4-tert-butylphenyl) 4-phenyltriazole, 3- (4-biphenylyl) -4-phenyl-5-tert-butylphenyl-1,2,4 -Triazole, 4-diphenylamino-benzaldehyde-N, N-diphenylhydrazone, 5, (4-diethylaminophenyl) -3- [2- (4-diethylaminophenyl) -ethenyl]- 1-phenyl-4,5-dihydro-1H-pyrazole, N, N'-di (4-methylphenyl) -N, N'-diphenyl-1,4-phenylenediamine, 4-dibenzylaminobenz Dehydrate-N, N-diphenylhydrazone, 4-dibenzylamino-3-methylbenzaldehyde-N, N-diphenylhydrazone, 4,4'-bis (carbazol-9-yl) biphenyl, N, N, N ', N'-tetraphenylbenzidine, N, N'-bis (4-methylphenyl) -N, N'-bis (phenyl) -benzidine, N, N'-bis (3-methylphenyl) -N, N'-bis (phenyl) benzidine, N, N, N ', N'-tetrakis (4-methylphenyl) benzidine, N, N, N', N'-tetrakis (3-methylphenyl) benzidine, di (4 -Dibenzylaminophenyl) ether, N, N'-di (naphthalen-2-yl) -N, N'-diphenylbenzidine, N, N'-di (naphthalen-1-yl) -N, N'- Diphenylbenzidine, 1,3-bis (4 (4-diphenylamino) phenyl-1,3,4-oxadiazol-2-yl) benzene, N, N'-di (naphthalen-2-yl), N, N'-di (3-methylphenyl) benzidine, N, N'-di (naphthalen-1-yl) -N, N'-di (4-methylphenyl) benzidine, N, N '-(dinanaphthalene-2 -Yl) -N, N'-di (3-methylphenyl) benzidine, 1,1-bis (4-bis (4-methylphenyl) aminophenyl) cyclohexane, 4,4 ', 4 "-tris (carbazole- 9-yl) -triphenylamine, 4,4 ', 4 "-tris (N, N-diphenylamino) -t Phenylamine, N, N'-bis (biphenyl-1-yl) -N, N-bis (naphth-1-yl) benzidine, 4,4 ', 4 "-tris (N-3-methylphenyl-N -Phenylamino) triphenylamine, N, N, N ', N'-tetrakis (biphenyl-4-yl) benzidine, 4,4', 4 "-tris (N- (1-naphthyl) -N -Phenylamino) triphenylamine, 4,4 ', 4 "-tris (N- (2-naphthyl) -N-phenylamino) triphenylamine, etc., which can be used alone or in combination of two or more in a certain ratio. It is good to add 3 to 30% by weight of the charge transfer layer coating liquid composition.

In the present invention, the binder resin and the solvent used in the charge transfer layer may be those used in the charge generation layer, and the preferred composition ratio is as described above. On the other hand, charge-gravity material plays a role of improving the durability of the drum by speeding up the response by light and reducing the fatigue by light. The charge attraction material can be used as an additive in both the charge generating layer and the charge transfer layer, and may be tetracyanoethylene, tetracyanoquinomimethane, anthraquinone, o-dicyanobenzene, p-dicyanobenzene, 2,6, 2 ', 6'-tetraphenyldiphenoquinone, succinate anhydride, maleic anhydride, dibromomaleic anhydride, phthalic anhydride, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, 3-nitrophthalic anhydride, 4-nitrophthalic anhydride , m-dinitrobenzene, p-dinitrobenzene, 1,3,5-trinitrobenzene, p-nitrobenzonitrile, quinonechloroimide, chloranyl, bromanyl, dichlorodicyano-p-benzoquinone, anthraquinone , Dinitroanthraquinone, 2,7-dinitro fluorenone, 2,4,7-trinitrofluorenone, 2,4,5,7-tetranitrofluorenone, 2- (2-phenylbenzo [5,6- b] -4H-thiopyran-4-ylidene) -propanedinitrile-1,1-dioxide, 4,4 '-(1,2-ethanediylidene) -bis (2,6-dimethyl-2,5-cyclohexadien-1-one), 2- (4-methylphenyl) -6-phenyl-4H-thiopyran-4-ylidene] -propanedinitrile-1,1 -Dioxide, 2- (4- (1-methylethyl) phenyl) 6-phenyl-4H-thiopyran-4-ylidene] -propanedinitrile-1,1-dioxide, etc. are mentioned, 0.01-5 Use weight percent.

Antioxidant is an antioxidant that can be used to prevent the deterioration of coating film caused by ozone generation by corona charging and to prevent oxidation by use of drum. It is a phenol-based and amine-based primary antioxidant and thioester-based , A phosphite secondary antioxidant may be used alone or in combination with a primary antioxidant and a secondary antioxidant in a ratio of preferably 1: 2. Antioxidants that can be used include N, N'-diphenyl-para-phenylenediamine, phenyl-alpha-naphthylamine, 4,4'-dioctyldiphenylamine, 2,6-dibutylbutyl-4-methyl Phenol, 2,2'-methylene-bis (4-methyl-6-tertiarybutyl) phenol, n-octadecyl-3- (3,5-dibutylbutyl-4-hydroxyphenyl) propionate, 1 , 3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) -1,3,5-triazine-2,4,6- (1H, 3H, 5H) -tree On, tris (3,5-dibutylbutyl-4-hydroxybenzyl) isocyanurate, 2,2'-isobutylidene-bis (4,6-dimethylphenol), 4,4'-butylidene -Bis (2-tert-butylbutyl-5-methylphenol), pentaerythryl-tetrakis-3- (3 ', 5'-dibutylbutyl-4'-hydroxyphenyl) propionate, 3,9 -Bis [2- [3- (3-tertylbutyl-4-hydroxy-5-methylphenyl) -propionyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [ 5.5] undecane, 2,5-diterylylhydroquinone, 1,1,3-tris (2-methyl-4-hydroxy-5-tertiary Butylphenyl) butane, 2,2'-methylene-bis (6- (1-methylcyclohexyl) -paracresol, 2,5-di-t-amylhydroquinone, 1,1,3-tris (2-methyl- 4-hydroxy-5-t-butylphenyl) butane, 2,2'-methylene-bis (6- (1-methylcyclohexyl) paracresol, 2-t-butyl-6- (3-t-butyl- 2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2- [1- (2-hydroxy-3,5-di-t-pentylphenyl) ethyl] -4,6-di-t- Pentylphenyl acrylate, 4,4'-thiobis (3-methyl-6-t-butylphenol), diphenyl monooctyl phosphite, tris (mono and dinonylphenyl) phosphite, distearyl pentaerythritol depot Spite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, tris (2,4-di-t-butylphenyl) phosphite, trisnonyl phenyl phosphite, 2,2'-methylene -Bis (4,6-di-t-butylphenyl) octyl phosphite, triphenyl phosphite, distearyl-3,3'-thiodipropionate, pentaerythritol tetrakis (3-la Ylthiopropionate), ditridecyl 3,3'-thiodipropionate, dilauryl 3,3'-thiodipropionate, dimyristyl 3,3'-thiodipropionate, 4, 4'-thiobis (3-methyl-6-t-butylphenyl) -1,1'-di (stearyl or myristyl) thiopropionate, alpha-tocopherol, ascorbic acid, beta-carotene, bis ( Dimethylaminophenyl) (aminomethyldithione) nickel and the like are used in 0.01 to 5% by weight.

Hereinafter, the method of manufacturing the charge transfer layer will be described in more detail. 5 to 50 weight percent of the binder resin, 3 to 30 weight percent of the two or more charge transfer materials, 0.01 to 5 weight percent of the antioxidant, 0.01 to 5 weight percent of the charge attraction material, solvent 10 Melt 91.8 weight percent together and coat evenly on the charge generating layer by sedimentation coating. After coating the charge transfer layer, it is dried at 50 to 200 ° C. for 0.1 to 4 hours. The thickness of the charge generating layer thus prepared is 10-40 micrometers. The electrophotographic photosensitive drum comprising the insulating layer, the charge generating layer, and the charge transfer layer has excellent photosensitivity, maintains high attenuation, and can be usefully used for photosensitive drums such as copiers, laser printers, and facsimile machines.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1

5 parts by weight of X-type metal-free phthalocyanine (Fastogen Blue 8120BS: Dainippon Ink & Chemicals, Inc.) together with 50 parts by weight of 1-methoxy-2-propanol was heat-converted at 100 ° C. for 72 hours, and then polyvinylbutylal resin (Esrec BH-3: 3.2 parts by weight of Sekisui Kagaku Kogyo Kabushiki Kaisha and 41.8 parts by weight of 1-methoxy-2-propanol were ball milled together with 300 parts by weight of glass beads (0.5 to 0.75 mm) for 3 hours. This dispersion was diluted with 100 parts by weight of 1-methoxy-2-propanol and injected with ultrasonic waves for 30 minutes to prepare a stable coating solution. The charge generating layer coating liquid is uniformly coated on an aluminum drum coated with polyamide firstly by using the sedimentation coating method and then dried at 130 ° C. for 30 minutes. Charge transfer layer is 4-dibenzylamino-2-methylbenzaldehydediphenylhydrazone (CTC191: ANAN CORPORATION) 4.5 parts by weight, 1,1-bis- (para-diethylaminophenyl) -4,4-diphenyl- 4.5 parts by weight of 1,3-butadiene (T405: ANAN CORPORATION), 10.5 parts by weight of polycarbonate (PCZ-400: Mitsubishi Gas Kagaku Kabushiki Kaisha), 0.5 parts by weight of tetracyanoquinodimethane, n-octadecyl-3- ( 0.2 parts by weight of 3,5-dibutylbutyl-4-hydroxyphenyl) propionate (IRGANOX1076: Ciba-Geigy), 0.1 part by weight of diphenyl monooctyl phosphite (MARK C: Asahi Denka), 55.7 weight of tetrahydrofuran 24 parts by weight of toluene were stirred together to completely dissolve and then coated on the charge generating layer. This drum is dried for 30 minutes at 120 degreeC. The electrophotographic photosensitive drum was charged with a -6KV corona with an electrostatic charge tester (Cynthia 91KSE: Gentec), adjusted to 780 nm of light at 1 kHz, and then scanned into the drum to measure photosensitivity, dark attenuation, and residual potential. E _1/2 is determined at the time it takes for the initial surface potential to decrease to 1/2 and E _1/5 is reduced to 1/5, and the residual potential is measured by measuring the potential 5 seconds after light scanning. It is shown in Table 1.

Example 2

In Example 1, it carried out similarly to Example 1 except having used the binder resin 3 weight part of polyvinyl butylal, and 2 weight part of butylated urea resins.

Example 3

In Example 1, the same procedure as in Example 1 was carried out except that heat conversion was performed at 100 ° C. for 138 hours.

Example 4

In Example 1, heat conversion was carried out at 100 ° C. for 97 hours, and the same procedure as in Example 1 was performed except that 3.5 parts by weight of polyvinyl butyral thial resin and 1.5 parts by weight of styrene-acrylic resin were used as the binder resin.

Comparative Example 1

10 parts by weight of X-type metal-free phthalocyanine, 3.5 parts by weight of polyvinyl butylal, and 86.5 parts by weight of 1-methoxy-2-propanol are milled together with 300 parts by weight of glass beads (0.5 to 0.75 mm ψ) in a paint shaker for 3 hours. The dispersion was diluted with 100 parts by weight of 1-methoxy-2-propanol and then ultrasonically scanned for 30 minutes to prepare a stable coating solution. This coating solution is first coated on a polyamide-coated aluminum drum using the sedimentation coating method and then dried in an oven at 130 ° C. for 30 minutes. Coating of the charge transfer layer was carried out in the same manner as in Example 1.

Comparative Example 2

It carried out similarly to the comparative example 1 except having milled for 14 hours in the paint shaker in the comparative example 1.

Comparative Example 3

Comparative Example 1 was carried out in the same manner as in Comparative Example 1 except that 3.5 parts by weight of polyvinyl butylal and 1.5 parts by weight of butylated urea resin were used.

 Characteristics  Example 1  Example 2  Example 3  Example 4  Comparative Example 1  Comparative Example 2  Comparative Example 3  Residual potential  Vr (-V)  12  9  9  6  20  18  16   Sensitivity E _1/2 (μJ / ㎠)  0.58  0.57  0.50  0.49  0.91  0.87  0.71 E _1/5 (μJ / ㎠)  1.16  1.13  1.01  0.96  1.90  1.82  1.46   Attenuation DD ₁ (%)  96.9  97.2  96.6  97.4  95.5  97.7  92.2 DD ₅ (%)  92.2  92.7  92.7  94.0  88.3  93.0  82.3

Vr (-V): Residual potential-surface potential 5 seconds after light irradiation

E _1/2 (μJ / ㎠): 1/2 attenuation light sensitivity

E _1/5 (μJ / ㎠): 1/5 attenuation light sensitivity

DD ₁ (%): Darkness attenuation (V ₁ / V ₀ ) × 100, V ₀ : Initial surface potential, V ₁ : Maximum surface potential 1 second after surface potential

DD ₅ (%): Darkness (V ₅ / V ₀ ) × 100, V ₀ : Initial surface potential, V ₅ : Surface potential after 5 seconds maximum surface potential

As confirmed through the results of Table 1, the novel crystalline metal-free phthalocyanine of the present invention has excellent photosensitivity compared to the X-type metal-free phthalocyanine, the electrophotographic photosensitive drum produced by the present invention has a fast printing speed It is suitable for the requirements and has excellent attenuation characteristics, so there is an advantage in that the resolution of the printed image is excellent.

Claims (8)

Beta- or X-type metal-free phthalocyanine was prepared by thermal conversion at 50 to 200 ° C. for 1 to 200 hours, and the 2θ (bragg angle: ± 0.2 degrees) value was 7.3, 8.8, 16.4, 17.1, 20.0, 20.5, at the X-ray diffraction peak. Metal-free phthalocyanines that are 21.2, 21.9, 23.6, 27.1, 28.3, 30.1. In an electrophotographic photosensitive drum consisting of a conductive substrate / insulation layer / charge generation layer / charge transfer layer or conductive substrate / charge generation layer / charge transfer layer, the charge generation layer comprises the crystalline metal-free phthalocyanine of claim 1 as a charge generating material. It is formed using a coating solution formed by adding a binder resin and a solvent, and the charge transfer layer is formed using a coating solution composed of two or more types of charge transfer materials, binder resins, charge labor materials, antioxidants and solvents. Electrophotographic photosensitive drum. 3. The electron of claim 2, wherein the charge generating layer is formed by coating with a stabilized coating solution composed of 2 to 40 wt% of a metal-free phthalocyanine, 1 to 55 wt% of a binder resin, and 5 to 97 wt% of a solvent. Photosensitive drum. The method of claim 2, wherein the charge transfer layer is 3 to 30% by weight of the charge transfer material, 5 to 50% by weight of the binder resin, 0.01 to 5% by weight of the charge attraction material, 0.01 to 5% by weight of the antioxidant and 10 to 91.8% by weight of the solvent An electrophotographic photoconductor drum, characterized in that formed by coating with a coating solution composed of%. 3. An electrophotographic photosensitive drum according to claim 2, wherein said charge transfer layer is formed of two or more types of said charge transfer materials. 6. The electrophotographic photosensitive drum according to claim 5, wherein the charge transfer material is a mixture of hydrazone and butadiene in a ratio of 1: 0.1 to 1: 5 by weight. 3. The electrophotographic photosensitive drum according to claim 2, wherein the binder resin is a mixture of polyvinylbutylal resin and styrene-acrylic resin in a 1: 0.1 to 1:10 weight ratio. 3. The electrophotographic photosensitive drum according to claim 2, wherein the antioxidant is a combination of a primary antioxidant and a secondary antioxidant in a weight ratio of 1: 2.