CN103869639B - Electrophotographic photosensitive element, handle box, electronic photographing device and phthalocyanine crystal - Google Patents

Abstract

The present invention relates to an electrophotographic photosensitive member, a process cartridge, an electrophotographic apparatus, and a phthalocyanine crystal. An electrophotographic photosensitive member includes a support, and a charge generating layer and a charge transporting layer formed on the support. The charge generating layer contains a specific amine compound.

Description

Electrophotographic photosensitive member, process cartridge, electrophotographic apparatus, and phthalocyanine crystal

technical field

The present invention relates to an electrophotographic photosensitive member, a process cartridge and an electrophotographic apparatus each having an electrophotographic photosensitive member, and to a phthalocyanine crystal.

Background technique

Since semiconductor lasers generally used in image exposure devices of electrophotographic photosensitive members have long oscillation wavelengths in the range of 650 to 820 nm, electrophotographic photosensitive members having high sensitivity to light in the long wavelength range are currently under development. Recently, an electrophotographic photosensitive member having high sensitivity to light of a short oscillation wavelength semiconductor laser is also under development to realize high-resolution images.

Azo pigments and phthalocyanine pigments are known as charge generating substances having high sensitivity to light in a range from a long wavelength region to a short wavelength region.

Although electrophotographic photosensitive members using azo pigments or phthalocyanine pigments have excellent photosensitivity, there is a problem that generated photocarriers tend to remain in the photosensitive layer to act as memory, easily causing potential fluctuations such as ghosting in some cases.

In order to solve the problems of phthalocyanine pigments, phthalocyanine pigments are used in combination with specific azo pigments.

Acetophenone compounds used in electrophotographic photosensitive members are described in Japanese Patent Application Laid-Open No. S59-30541, Japanese Patent Application Laid-Open No. 2007-138153, and Japanese Patent Application Laid-Open No. 2009-301016 .

Japanese Patent Application Laid-Open No. S59-30541 describes an acetylated benzene derivative used as an absorption wavelength shifting agent for a phthalocyanine vapor deposition film.

Japanese Patent Application Laid-Open No. 2007-138153 describes a phthalocyanine crystal precursor having a main peak at a Bragg angle 2θ of 27.2° in X-ray diffraction using CuKα radiation produced by contacting a phthalocyanine crystal precursor with a fluorobenzene derivative. Oxytitanium phthalocyanine crystals. According to its description, the oxytitanium phthalocyanine crystal thus prepared has improved crystal stability and improved sensitivity.

According to Japanese Patent Application Laid-Open No. 2009-301016, an α-aminoacetophenone compound is added as a polymerization initiator to a protective layer of a photosensitive member to improve hardenability.

As described above, various attempts have been made to improve electrophotographic photosensitive members. In recent years, in order to further improve high-quality images, it is desired to prevent image degradation due to ghosting in various environments.

Contents of the invention

An object of the present invention is to solve the above-mentioned problems and provide an electrophotographic photosensitive member that reduces image defects due to ghosting not only under normal temperature and normal humidity environments but even under low temperature and low humidity environments, especially severe conditions. Another object of the present invention is to provide a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member. Another object of the present invention is to provide a phthalocyanine crystal containing a specific amine compound in the crystal.

The present invention provides an electrophotographic photosensitive member comprising: a support; and a charge generating layer and a charge transporting layer formed on the support; wherein the charge generating layer contains a charge generating substance and an amine compound represented by the following formula (1):

In formula (1), R ¹ to R ⁵ each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group group, substituted or unsubstituted aryloxy group, substituted amino group, or substituted or unsubstituted cyclic amino group. At least one of R ¹ to R ⁵ is an amino group substituted with a substituted or unsubstituted aryl group, an amino group substituted with a substituted or unsubstituted alkyl group, or a substituted or unsubstituted cyclic amino group.

The present invention also provides a process cartridge detachably mountable to a main body of an electrophotographic apparatus, wherein the process cartridge integrally supports an electrophotographic photosensitive member and an element selected from the group consisting of a charging device, a developing device, a transferring device, and a cleaning device. at least one device.

The present invention also provides an electrophotographic apparatus having an electrophotographic photosensitive member with charging means, image exposing means, developing means, and transfer means.

The present invention also provides a phthalocyanine crystal containing a compound represented by formula (1) in the crystal.

The present invention can provide an electrophotographic photosensitive member that reduces image defects due to ghosting not only under normal temperature and normal humidity environments but also under low temperature and low humidity environments, especially severe conditions. The present invention can also provide a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member. The present invention can also provide a phthalocyanine crystal having excellent characteristics as a charge generating substance.

Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings.

Description of drawings

FIG. 1 is a schematic view of an electrophotographic apparatus provided with a process cartridge having an electrophotographic photosensitive member.

Fig. 2 is a powder X-ray diffraction pattern of the hydroxygallium phthalocyanine crystal obtained in Example 1-1.

Fig. 3 is a powder X-ray diffraction pattern of the hydroxygallium phthalocyanine crystal obtained in Reference Example 1-1.

detailed description

Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

The amine compound contained in the charge generating layer of the electrophotographic photosensitive member of the present invention has a structure represented by the following formula (1).

In formula (1), R ¹ to R ⁵ each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group group, substituted or unsubstituted aryloxy group, substituted amino group, or substituted or unsubstituted cyclic amino group. At least one of R ¹ to R ⁵ is an amino group substituted with a substituted or unsubstituted aryl group, an amino group substituted with a substituted or unsubstituted alkyl group, or a substituted or unsubstituted cyclic amino group.

At least one of R ¹ to R ⁵ in formula (1) may be an amino group substituted with a substituted or unsubstituted alkyl group. More preferably, the amino group substituted with a substituted or unsubstituted alkyl group is especially a dialkylamino group.

Further preferably, the dialkylamino is dimethylamino or diethylamino.

More preferably, the amine compound is specifically an amine compound represented by the following formula (2).

In formula (2), R ⁶ or R ⁷ each independently represent a methyl group or an ethyl group.

At least one of R ¹ to R ⁵ in formula (1) may be a substituted or unsubstituted cyclic amino group. Examples of substituted or unsubstituted cyclic amino groups include substituted or unsubstituted piperazinyl, substituted or unsubstituted pyrrolidinyl, substituted or unsubstituted pyrrolyl, substituted or unsubstituted triazolyl, substituted or unsubstituted Imidazolyl, substituted or unsubstituted pyridyl, substituted or unsubstituted pyrazinyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted triazinyl, substituted or unsubstituted quinolinyl, substituted or unsubstituted Indolinyl, substituted or unsubstituted acridinyl, substituted or unsubstituted morpholinyl (morpholinyl group), substituted or unsubstituted piperidinyl, morpholino group, and substituted or Unsubstituted piperidino group. The cyclic amino group may be a 3 to 8-membered cyclic amino group. At least one carbon atom constituting the ring may be substituted with an oxygen atom, a nitrogen atom, or the like. A morpholino group or a piperidino group which is a six-membered ring amino group is particularly preferred.

More preferably, the amine compound is an amine compound represented by the following formula (3).

Examples of the substituents for each of the substituted alkyl group, substituted alkoxy group, substituted aryloxy group, substituted amino group, substituted aryl group and substituted cyclic amino group in formula (1) may include alkyl groups such as methyl, ethyl, radical, propyl and butyl, aralkyl such as benzyl, alkoxy such as methoxy and ethoxy, dialkylamino such as dimethylamino and diethylamino, alkoxycarbonyl such as methoxy Carbonyl and ethoxycarbonyl, phenyl, naphthyl, biphenyl, nitrophenyl, tolyl, bromophenyl, cyanophenyl, methoxyphenyl, acetylphenyl, nitro, cyano , formyl group, alkoxy group, acetyl group, halogen atom such as fluorine atom, chlorine atom and bromine atom, hydroxyl group and halomethyl group. In particular alkyl groups are preferred substituents.

The charge generating layer of the present invention may be a layer including a phthalocyanine crystal containing an amine compound represented by formula (1) in the crystal.

Preferred substituents of R ¹ to R ⁵ in formula (1) contained in the phthalocyanine crystal are the same as those of the amine compound represented by formula (1) contained in the charge generation layer.

Although specific examples (exemplary compounds) of the amine compound contained in the charge generating layer of the electrophotographic photosensitive member of the present invention and the amine compound contained in the phthalocyanine crystal are described below, the present invention is not limited thereto.

The amine compound used in the present invention may be commercially available or may be synthesized, for example, as described below.

Aminoacetophenone was used as starting material. A substituent can be introduced to the amino group by a substitution reaction between aminoacetophenone and a halide. The reaction between aminoacetophenones and aromatic halides in the presence of metal catalysts is particularly useful for the synthesis of aryl-substituted amine compounds. Alternatively, reductive amination reactions are useful for the synthesis of alkyl-substituted amine compounds.

Alternatively, haloacetophenones are used as starting materials. An amino group can be introduced at the position of a halogen by a substitution reaction between a haloacetophenone and an amine.

A specific synthesis example of the exemplary compound (3) is described below. In the synthesis examples, "parts" means "parts by mass". Infrared (IR) absorption spectrum was measured with a Fourier transform infrared spectrometer (trade name: FT/IR-420, manufactured by Jasco Corporation). Nuclear magnetic resonance (NMR) spectrum was measured with a nuclear magnetic resonance apparatus (trade name: R-90, manufactured by Hitachi, Ltd).

[Synthesis Example 1]

Synthesis of Exemplary Compound (3)

Under nitrogen flow, in an eggplant-shaped flask containing 1,500 parts of toluene, 344 parts of dry cesium carbonate, 3.4 parts of palladium acetate, 13 parts of (s)-BINAP (2,2'-bis(diphenylphosphino)-1 , 1'-binaphthyl), 150 parts of 4'-bromoacetophenone, 100 parts of morpholine. The mixture was heated and stirred at 100°C for 15 hours. After cooling, 500 parts of chloroform was added and the reaction liquid was filtered with a filter covered with celite. The solvent in the filtrate was distilled off under reduced pressure. The residue was purified in a silica gel column (solvent: toluene/ethyl acetate) to obtain 82 parts of yellow crystals of exemplary compound (3).

The measured IR absorption spectrum and the characteristic peaks of the measured ¹ H-NMR spectrum are described below.

IR (cm ^-1 , KBr): 2844, 1661, 1600, 1244, 1121, 930, 822

¹ H-NMR (ppm, CDCL ₃ ): δ=7.88 (d, 2H), 6.86 (d, 2H), 3.8-3.9 (m, 4H), 3.2-3.4 (m, 4H), 2.52 (s, 3H) )

The charge generating substance contained in the charge generating layer may be a phthalocyanine pigment or an azo pigment because of high sensitivity. In particular, phthalocyanine pigments or phthalocyanine crystals are more preferred.

Examples of phthalocyanine pigments or phthalocyanine crystals include metal-free phthalocyanines and metal phthalocyanines which may contain axial ligands or substituents. Among phthalocyanine pigments and phthalocyanine crystals, oxytitanium phthalocyanine crystals and gallium phthalocyanine crystals are preferable, and they are effective in the present invention because they have excellent sensitivity although they tend to cause ghosting.

Among gallium phthalocyanine crystals, hydroxygallium phthalocyanine crystals of a crystal form having peaks at Bragg angles 2θ of 7.4°±0.3° and 28.2°±0.3° in X-ray diffraction with CuKα radiation are preferable, and X-rays with CuKα radiation Chlorogallium phthalocyanine crystal of crystal form having peaks at Bragg angles 2θ±0.2° of 7.4°, 16.6°, 25.5° and 28.3° in diffraction. Among the oxytitanium phthalocyanine crystals, oxytitanium phthalocyanine crystals having a crystal form having a peak at a Bragg angle 2θ of 27.2°±0.2° are preferable.

In particular, a hydroxygallium phthalocyanine crystal of a crystal form having peaks at Bragg angles 2θ of 7.4°±0.3° and 28.2°±0.3° is preferable.

In particular, a hydroxygallium phthalocyanine crystal of a crystal form having peaks at Bragg angles 2θ±0.2° of 7.3°, 24.9° and 28.1°, and having the strongest peak at 28.1° is more preferable. Further, hydroxygallium phthalocyanine crystals of a crystal form having peaks at Bragg angles 2θ±0.2° of 7.5°, 9.9°, 16.3°, 18.6°, 25.1° and 28.3° are also preferred.

Examples of the phthalocyanine constituting the phthalocyanine crystal containing the amine compound represented by formula (1) in the crystal include metal-free phthalocyanine and metal phthalocyanine which may have an axial ligand. Phthalocyanine may have a substituent. Particularly preferred are oxytitanium phthalocyanine crystals and gallium phthalocyanine crystals, which tend to cause ghost images but have excellent sensitivity and are effective for the present invention.

Examples of the gallium phthalocyanine constituting the gallium phthalocyanine crystal containing the amine compound represented by formula (1) in the crystal include gallium phthalocyanine molecules in which the gallium atom has a halogen atom, a hydroxyl group, or an alkoxy axis ligand, as described below. The phthalocyanine ring may contain substituents such as halogen atoms.

A gallium phthalocyanine crystal further comprising N,N-dimethylformamide in the crystal is preferable.

Among gallium phthalocyanine crystals, hydroxygallium phthalocyanine crystals, bromogallium phthalocyanine crystals and iodogallium phthalocyanine crystals are preferable, which have excellent sensitivity and are effective for the present invention. In particular, hydroxygallium phthalocyanine crystals are preferred. Hydroxygallium phthalocyanine crystals contain gallium atoms with hydroxyl-axis ligands. Bromogallium phthalocyanine crystals contain gallium atoms with bromine atom axis ligands. Iodogallium phthalocyanine crystals contain gallium atoms with iodine atom axis ligands.

Of the hydroxygallium phthalocyanine crystals, particularly, hydroxygallium phthalocyanine crystals having peaks at Bragg angles 2θ of 7.4°±0.3° and 28.3°±0.3° in X-ray diffraction with CuKα radiation, which have a decrease due to Effect of image defects caused by ghosting.

The content of the amine compound represented by the formula (1) contained in the phthalocyanine crystal may be 0.05% by mass or more and 3.0% by mass or less.

In the phthalocyanine crystal containing the amine compound represented by the formula (1) in the crystal, the amine compound represented by the formula (1) is introduced into the crystal.

A method for producing a phthalocyanine crystal containing an amine compound represented by formula (1) in the crystal is described below. The phthalocyanine crystal containing the amine compound represented by the formula (1) in the crystal can be obtained by mixing phthalocyanine prepared by acid pasting and the amine compound represented by the formula (1) with a solvent and treating it by a wet grinding method. Obtained by transforming into crystals.

The grinding treatment is a treatment using dispersion materials such as glass beads, steel balls and alumina balls in a grinding device such as a sand mill and a ball mill. Grinding time can be from about 10 to 60 hours. In a particularly preferred method, samples are taken at intervals of 5 to 10 hours to check the Bragg angle of the crystals. The amount of the dispersed material in the grinding process may be 10 to 50 times by mass of gallium phthalocyanine. Examples of solvents used include amide-based solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methylformamide, N-methylacetamide, and N-methylpropionamide , halogen-based solvents such as chloroform, ether-based solvents such as tetrahydrofuran, and sulfoxide-based solvents such as dimethyl sulfoxide. The amount of the solvent used may be 5 to 30 times by mass of the phthalocyanine. The amount of the amine compound represented by the formula (1) used may be 0.1 to 30 times by mass of the phthalocyanine.

In the present invention, the measurement data of the phthalocyanine crystal obtained by NMR measurement and thermogravimetric (TG) measurement are analyzed to determine whether the phthalocyanine crystal of the present invention contains the amine compound represented by formula (1) in the crystal.

For example, NMR measurement of the resulting phthalocyanine crystal is performed when the amine compound represented by the formula (1) is dissolved in a solvent for grinding treatment or when washing is performed after grinding. When the compound represented by the formula (1) is detected from the obtained phthalocyanine crystal, it is judged that the amine compound represented by the formula (1) is contained in the crystal.

On the other hand, when the amine compound represented by formula (1) is insoluble in the solvent used in the grinding treatment and insoluble in the cleaning solvent after grinding, NMR measurement of the resulting phthalocyanine crystal is performed. When the amine compound represented by the formula (1) is detected, it is judged by the following method.

Phthalocyanine crystals obtained by adding an amine compound represented by formula (1) alone, phthalocyanine crystals prepared in the same manner except that the amine compound represented by formula (1) was not added, and only amine represented by formula (1) Individual TG measurements of compounds. When the TG measurement result of the phthalocyanine crystal obtained by adding the amine compound is interpreted as a mixture of a predetermined ratio of the individual measurement results of the phthalocyanine crystal and the amine compound prepared without adding the amine compound, it is judged as a phthalocyanine crystal and an amine compound A simple mixture or amine compound is formed to attach to the surface of the phthalocyanine crystal.

On the other hand, when the TG measurement result of the phthalocyanine crystal obtained by adding the amine compound shows that the weight reduction is completed at a temperature higher than that of the amine compound alone, compared with the TG measurement result of the phthalocyanine crystal prepared without the amine compound When the weight loss increases at a temperature of , it is judged that the amine compound represented by the formula (1) is contained in the crystal.

TG measurement, X-ray diffraction analysis, and MR measurement of the phthalocyanine crystal of the present invention were performed under the following conditions.

[TG measurement]

Measuring instrument: Simultaneous TG/DTA measuring device (manufactured by Seiko Instruments Inc). (Product name: TG/DTA 220U)

Atmosphere: nitrogen flow (300cm ³ /min)

Measuring range: 35°C to 600°C

Temperature rise rate: 10°C/min

[Powder X-ray Diffraction Analysis]

Measuring instrument: X-ray diffraction analyzer RINT-TTRII (manufactured by Rigaku Corporation)

X-ray tube: Cu

X-ray tube voltage: 50KV

X-ray tube current: 300mA

Scanning method: 2θ/θ scanning

Scan rate: 4.0°/min

Sampling interval: 0.02°

Starting angle (2θ): 5.0°

Stop angle (2θ): 40.0°

Accessories: standard sample stage

Filter: not used

Incident monochrome: use

Counter monochromator: not used

Divergence Slit: Open

Longitudinal divergence limiting slit: 10.00mm

Scatter Slit: Open

Light receiving slit: open

Flat panel monochromator: use

Counter: Blink Counter

[NMR measurement]

Measuring instrument: AVANCE III 500 (manufactured by Bruker)

Solvent: heavy sulfuric acid (D ₂ SO ₄ )

A phthalocyanine crystal containing the compound represented by formula (1) of the present invention in the crystal has excellent functions as a photoconductor, and is applicable to solar cells, sensors, switching devices, etc. in addition to electrophotographic photosensitive members.

The electrophotographic photosensitive member of the present invention includes, as a photosensitive layer, a charge generating layer containing a charge generating substance and a charge transporting layer containing a charge transporting substance. While either of the charge generating layer and the charge transporting layer may be the upper layer (surface side), it is more preferable that the charge generating layer is the lower layer (support body side).

A conductive support (conductive support) is suitably used. Examples of the conductive support include those made of metal (alloy) such as aluminum and stainless steel, and those made of metal, alloy, plastic or paper whose surface is coated with a conductive film. The shape of the support may be, for example, a cylindrical shape or a film shape.

An undercoat layer (also referred to as an intermediate layer) having a barrier effect and an adhesive effect may be disposed between the support and the photosensitive layer (charge transport layer or charge generation layer).

The undercoat layer can be formed by applying a coating liquid for undercoat layer formation on a support or a conductive layer described below and drying the obtained coating film. The coating liquid can be prepared by dissolving a resin in a solvent. Examples of resins include polyvinyl alcohol, polyethylene oxide, ethyl cellulose, methyl cellulose, casein, polyamide, gum, and gelatin. The undercoat layer may have a film thickness of 0.3 to 5.0 μm.

A conductive layer may be disposed between the support and the undercoat layer to cover irregularities and defects on the surface of the support and reduce interference fringes.

The conductive layer can be formed by applying a coating liquid for forming a conductive layer on a support and drying and curing the prepared coating film. The coating liquid for forming a conductive layer can be prepared by dispersing conductive particles such as carbon black, metal particles, and metal oxide particles, and a binder resin in a solvent. The conductive layer may have a film thickness of 5 to 40 μm, more preferably 10 to 30 μm.

The charge generating layer can be formed by applying a coating liquid for forming a charge generating layer and drying the obtained coating film. The coating liquid for forming a charge generating layer can be prepared by dispersing an amine compound and a charge generating substance, or a phthalocyanine crystal containing an amine compound, and a binder resin in a solvent. The charge generation layer may have a film thickness of 0.05 to 1 μm, more preferably 0.1 to 0.3 μm.

The content of the amine compound in the charge generation layer may be 0.05% by mass to 15% by mass, more preferably 0.1% by mass to 10% by mass relative to the total mass of the charge generation layer. The content of the amine compound in the charge generating layer may be 0.1% by mass or more and 20% by mass or less, more preferably 0.3% by mass or more and 10% by mass or less, relative to the charge generating material.

The content of the charge generating substance in the charge generating layer may be 30% by mass or more and 90% by mass or less, more preferably 50% by mass or more and 80% by mass or less, relative to the total mass of the charge generating layer.

The amine compound contained in the charge generation layer may be amorphous or crystalline. Two or more amine compounds may be used in combination.

Examples of the binder resin used for the charge generating layer include polyester, acrylic resin, phenoxy resin, polycarbonate, polyvinyl butyral, polystyrene, polyvinyl acetate, polysulfone, polyarylene esters, vinylidene chloride, acrylonitrile copolymers, and polyvinyl benzal. Particular preference is given to polyvinyl butyral and polyvinyl benzal.

The charge transport layer can be formed by applying a charge transport layer forming coating liquid and drying the obtained coating film. The coating liquid for forming a charge transport layer can be prepared by dissolving a charge transport substance and a binder resin in a solvent.

The charge transport layer may have a film thickness of 5 to 40 μm, more preferably 10 to 25 μm.

The content of the charge transporting substance may be 20% by mass or more and 80% by mass or less, more preferably 30% by mass or more and 60% by mass or less, relative to the total mass of the charge transporting layer.

Examples of the charge transporting substance include triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, thiazole compounds, and triallylmethane compounds. In particular, triarylamine compounds are preferred.

Examples of the binder resin used for the charge transport layer include polyester, acrylic resin, phenoxy resin, polycarbonate, polystyrene, polyvinyl acetate, polysulfone, polyarylate, vinylidene chloride, Acrylonitrile copolymer. In particular, polycarbonate and polyarylate are preferred.

Examples of the application method of the coating liquid used to form each layer include a dip coating method (dip coating method), a spray coating method, a spin coating method, a bead coating method, a blade coating method, and a beam coating method.

A protective layer may be provided on the photosensitive layer (charge generation layer or charge transport layer) to protect the photosensitive layer.

The protective layer can be formed by applying, on the photosensitive layer, a protective layer-forming coating liquid prepared by dissolving a resin in a solvent, and drying and curing the prepared coating film. The coating film can be cured with heat, electron beam or ultraviolet rays. Examples of the resin used for the protective layer include polyvinyl butyral, polyester, polycarbonate (e.g., polycarbonate Z and modified polycarbonate), nylon, polyimide, polyarylate, polyurethane, Styrene-butadiene copolymer, styrene-acrylic acid copolymer and styrene-acrylonitrile copolymer.

The protective layer may have a film thickness of 0.05 to 20 μm.

The protective layer may contain conductive particles, ultraviolet absorbers, or lubricating particles such as resin particles containing fluorine atoms. Examples of conductive particles include metal oxide particles such as tin oxide particles.

FIG. 1 is a schematic view of an electrophotographic apparatus provided with a process cartridge having the electrophotographic photosensitive member of the present invention.

An electrophotographic photosensitive member 1 having a cylindrical shape (drum shape) is rotationally driven around an axis 2 at a predetermined peripheral speed (process speed) in an arrow direction.

During the spinning process, the surface of the electrophotographic photosensitive member 1 is electrostatically charged to a positive or negative predetermined potential with a charging device 3 . Subsequently, the surface of the electrophotographic photosensitive member 1 is irradiated with image exposure light 4 from an image exposure device (not shown in the figure) to form an electrostatic latent image corresponding to target image information. The image exposure light 4 is intensity-modulated corresponding to a time-series electrical digital image signal of target image information output from an image exposure device for slit exposure or exposure with a scanning laser beam, for example.

The electrostatic latent image formed on the surface of the electrophotographic photosensitive member 1 is developed with toner stored in the developing device 5 (normal development or reverse development) to form a toner image on the surface of the electrophotographic photosensitive member 1 . The toner image formed on the surface of the electrophotographic photosensitive member 1 is transferred to a transfer material 7 with a transfer device 6 . In this case, a bias voltage having a polarity opposite to that of the charge remaining on the toner is applied from a bias power source to the transfer device 6 (not shown in the figure). A transfer material 7 of paper is taken out from a paper feeding portion (not shown in the figure) in synchronization with the rotation of the electrophotographic photosensitive member 1 to be supplied between the electrophotographic photosensitive member 1 and the transfer device 6 .

The transfer material 7 having the toner image transferred from the electrophotographic photosensitive member 1 is separated from the surface of the electrophotographic photosensitive member 1 and conveyed to an image fixing device 8 for fixing the toner image. The image formation (print or copy) is thereby printed out from the electrophotographic apparatus.

After the toner image is transferred to the transfer material 7, the surface of the electrophotographic photosensitive member 1 is cleaned with a cleaning device 9 to remove adhering materials such as toner (toner remaining after transfer). In a recently developed cleaner-less system, the toner can be removed directly after transfer using a developing device or the like. Subsequently, the surface of the electrophotographic photosensitive member 1 is neutralized with pre-exposure light 10 from a pre-exposure device (not shown in the figure), and then repeatedly used for image formation. A pre-exposure device is not necessarily required for a contact charging device 3 with a charging roller.

A plurality of components selected from the group consisting of an electrophotographic photosensitive member 1, a charging device 3, a developing device 5, and a cleaning device 9 can be accommodated in a container and integrally supported to form a process cartridge detachably mounted to an electrophotographic apparatus main body . For example, at least one selected from the group consisting of the charging device 3 , the developing device 5 and the cleaning device 9 is integrally supported together with the electrophotographic photosensitive member 1 to form a cartridge. The cartridge constitutes a process cartridge 11 detachably mounted to the main body of the electrophotographic apparatus with guide means 12 such as a guide rail of the main body of the electrophotographic apparatus.

The image exposure light 4 may be a reflected light beam from a document of electrophotographic equipment such as copiers and printers or a transmitted beam of light transmitted through a document of electrophotographic equipment such as copiers and printers. Alternatively, the image exposure light 4 may be a radiation beam generated by scanning of a laser beam in response to a signal from a document reading sensor, driving of an LED array, or driving of a liquid crystal shutter array.

The electrophotographic photosensitive member 1 of the present invention can be widely used in electrophotographic application fields such as laser beam printers, CRT printers, LED printers, FAX, liquid crystal printers, and laser plate making.

[Example]

The present invention will be described in further detail with reference to the following specific examples, although the present invention is not limited thereto. The film thicknesses of the respective layers of the electrophotographic photosensitive members in Examples and Comparative Examples were obtained with an eddy current film thickness meter (Fischerscope, manufactured by Fischer Instrumens K.K.) or based on specific gravity converted from mass per unit area.

[Example 1-1]

Hydroxygallium phthalocyanine was prepared by the same treatment as in Synthesis Example 1 and subsequent Example 1-1 described in Japanese Patent Application Laid-Open No. 2011-94101. Then, 0.5 parts of hydroxygallium phthalocyanine, 1.0 parts of Exemplary Compound (1) (product code: D1575, manufactured by Tokyo Chemical Industry Co., Ltd.), 9.5 parts of N,N-dimethylformamide were put into a mixture with Fifteen parts of glass beads with a diameter of 0.8 mm were ground in a ball mill for 48 hours at room temperature (23° C.). Hydroxygallium phthalocyanine crystals were prepared from a dispersion in N,N-dimethylformamide. When filtering, the filter is thoroughly cleaned with tetrahydrofuran. The filter residue was vacuum-dried so as to obtain 0.5 part of hydroxygallium phthalocyanine crystals. The powder X-ray diffraction pattern of the prepared hydroxygallium phthalocyanine crystal is shown in FIG. 2 .

By NMR measurement, conversion based on the proton ratio confirmed that 0.39% by mass of Exemplary Compound (1) and 1.83% by mass of N,N-dimethylformamide were contained in the hydroxygallium phthalocyanine crystal. Since Exemplary Compound (1) is dissolved in N,N-dimethylformamide, it was found that Exemplary Compound (1) was contained in the hydroxygallium phthalocyanine crystal.

[Example 1-2]

Except that the exemplary compound (3) prepared in Synthesis Example 1 was used instead of the exemplary compound (1) in Example 1-1, 0.45 parts of hydroxygallium phthalocyanine was obtained by the same treatment as in Example 1-1 crystals. The powder X-ray diffraction pattern of the prepared hydroxygallium phthalocyanine crystal is the same as that in FIG. 2 .

By NMR measurement, it was confirmed that 0.42% by mass of Exemplary Compound (3) and 1.83% by mass of N,N-dimethylformamide were contained in the hydroxygallium phthalocyanine crystal. Since the exemplary compound (3) was dissolved in N,N-dimethylformamide, it was found that the exemplary compound (3) was contained in the hydroxygallium phthalocyanine crystal.

[Example 1-3]

0.45 parts of hydroxygallium phthalocyanine crystals were obtained by the same treatment as in Example 1-2, except that 0.5 parts of Exemplary Compound (3) was used instead of 1.0 part of Exemplary Compound (3) in Example 1-2. The powder X-ray diffraction pattern of the prepared hydroxygallium phthalocyanine crystal is the same as that in FIG. 2 .

By NMR measurement, it was confirmed that 0.23% by mass of Exemplary Compound (3) and 1.89% by mass of N,N-dimethylformamide were contained in the hydroxygallium phthalocyanine crystal.

[Reference example 1-1]

0.4 parts of hydroxygallium phthalocyanine crystals were obtained in the same treatment as in Example 1-1 except that 1.0 parts of Exemplary Compound (1) in Example 1-1 was not added. The powder X-ray diffraction pattern of the prepared hydroxygallium phthalocyanine crystal is shown in FIG. 3 .

[Example 2-1]

First, 60 parts of barium sulfate particles coated with tin oxide (trade name: Passtran PC1, manufactured by MitsuiMining & Smelting Co., Ltd.), 15 parts of titanium oxide particles (trade name: TITANIX JR, manufactured by Tayca Corporation), 43 parts Resole type phenolic resin (trade name: Phenolite J-325, manufactured by DIC Corporation, solid content: 70% by mass), 0.015 parts of silicone oil (trade name: SH28PA, manufactured by Dow Corning Toray Co., Ltd.), 3.6 parts Silicone resin (trade name: Tospearl 120, manufactured by Momentive Performance Materials Inc.), 50 parts of 2-methoxy-1-propanol, and 50 parts of methanol were put into a ball mill, and dispersed for 20 hours to prepare a conductive layer forming Coating solution.

The coating solution for forming a conductive layer was applied by dip coating on an aluminum cylinder (diameter: 24 mm) as a support, and the prepared coating film was dried at 140° C. for 30 minutes to form a conductive layer having a film thickness of 15 μm. layer.

Subsequently, 10 parts of copolymerized nylon resin (trade name: Amilan CM8000, manufactured by Toray Industries, Inc.) and 30 parts of methoxymethylated 6-nylon resin (trade name: Tresin EF-30T, manufactured by Nagase Chemtex Corporation ) was dissolved in a mixed solvent of 400 parts of methanol and 200 parts of n-butanol to prepare a coating liquid for undercoat layer formation.

The coating liquid for undercoat layer formation was applied to the conductive layer by dip coating, and the prepared coating film was dried to form an undercoat layer having a film thickness of 0.5 μm.

Subsequently, 10 parts of the hydroxygallium phthalocyanine crystal (charge generating substance) prepared in Example 1-1, 5 parts of polyvinyl butyral (trade name: S-LEC BX-1, manufactured by Sekisui Chemical Co. , Ltd.), and 250 parts of cyclohexanone were placed in a sand mill having glass beads having a diameter of 1 mm to be dispersed for 4 hours. To the dispersion liquid, 250 parts of ethyl acetate was added to dilute the dispersion liquid, thereby preparing a coating liquid for charge generation layer formation.

The coating liquid for charge generating layer formation was applied to the undercoat layer by dip coating. The prepared coating film was dried at 100° C. for 10 minutes to form a charge generation layer having a film thickness of 0.16 μm.

Subsequently, 8 parts of a compound represented by the following formula (4) (charge transporting substance) and 10 parts of polycarbonate (trade name: Iupilon Z-200, manufactured by Mitsubishi Engineering-Plastics Corporation) were dissolved in 70 parts of monochlorobenzene to prepare A coating liquid for forming a charge transport layer.

The charge-transporting layer-forming coating liquid is applied to the charge-generating layer by dip coating. The prepared coating film was dried at 110° C. for 1 hour to form a charge transport layer having a film thickness of 23 μm.

A cylindrical (drum-shaped) electrophotographic photosensitive member of Example 2-1 was thus produced.

[Example 2-2]

In addition to using the hydroxygallium phthalocyanine crystal obtained in Example 1-2 to replace the hydroxygallium phthalocyanine crystal in Example 2-1 when preparing the coating liquid for forming the charge generation layer, the same method as in Example 2-1 The electrophotographic photosensitive member in Example 2-2 was produced in the same manner as in Example 2-2.

[Example 2-3]

In addition to using the hydroxygallium phthalocyanine crystal obtained in Example 1-3 instead of the hydroxygallium phthalocyanine crystal in Example 2-1 when preparing the coating liquid for forming the charge generation layer, the same method as in Example 2-1 The electrophotographic photosensitive member in Example 2-3 was produced in the same manner.

[Example 2-4]

The electrophotographic photosensitive member in Example 2-4 was produced in the same manner as in Example 2-1 except that the preparation of the charge generating layer-forming coating liquid in Example 2-1 was changed as follows.

First, 10 parts of the hydroxygallium phthalocyanine crystal (charge generating substance) prepared in Reference Example 1-1, 0.5 parts of exemplary compound (1), 5 parts of polyvinyl butyral (trade name: S-LEC BX -1, manufactured by Sekisui Chemical Co., Ltd.), and 250 parts of cyclohexanone were placed in a sand mill having glass beads having a diameter of 1 mm to be dispersed for 4 hours. Then, 250 parts of ethyl acetate was added to the dispersion liquid for dilution to prepare a coating liquid for charge generation layer formation.

[Example 2-5]

In the same manner as in Example 2-4, except that 1.0 part of Exemplary Compound (1) was used instead of 0.5 part of Exemplary Compound (1) in preparing the coating liquid for charge generation layer formation in Example 2-4 Electrophotographic photosensitive members in Examples 2-5 were produced.

[Example 2-6]

In the same manner as in Example 2-4, except that 0.1 part of Exemplary Compound (3) was used instead of 0.5 part of Exemplary Compound (1) when preparing the coating liquid for forming a charge generating layer in Example 2-4 Electrophotographic photosensitive members in Examples 2-6 were produced.

[Example 2-7]

In the same manner as in Example 2-4, except that 0.5 part of Exemplary Compound (3) was used instead of 0.5 part of Exemplary Compound (1) in preparing the coating liquid for forming a charge generating layer in Example 2-4 Electrophotographic photosensitive members in Examples 2-7 were produced.

[Example 2-8]

In the same manner as in Example 2-4, except that 1.0 part of Exemplary Compound (3) was used instead of 0.5 part of Exemplary Compound (1) in preparing the coating liquid for forming a charge generating layer in Example 2-4 Electrophotographic photosensitive members in Examples 2-8 were produced.

[Example 2-9]

In the same manner as in Example 2-4, except that 0.5 part of Exemplary Compound (6) was used instead of 0.5 part of Exemplary Compound (1) in preparing the coating liquid for forming a charge generating layer in Example 2-4 Electrophotographic photosensitive members in Examples 2-9 were produced.

[Example 2-10]

In the same manner as in Example 2-4, except that 0.5 part of Exemplary Compound (8) was used instead of 0.5 part of Exemplary Compound (1) in preparing the coating liquid for forming a charge generating layer in Example 2-4 Electrophotographic photosensitive members in Examples 2-10 were produced.

[Example 2-11]

Except that 0.5 part of the exemplary compound (9) (product code: D1446, manufactured by Tokyo Chemical Industry Co., Ltd.) was used instead of 0.5 part of the exemplary compound in Example 2-4 when preparing the coating liquid for charge generation layer formation Except for (1), the electrophotographic photosensitive member in Example 2-11 was produced in the same manner as in Example 2-4.

[Comparative Example 2-1]

Except that the hydroxygallium phthalocyanine crystal prepared in Reference Example 1-1 was used instead of the hydroxygallium phthalocyanine crystal in Example 2-1 when preparing the coating solution for forming the charge generation layer, the same method as in Example 2-1 An electrophotographic photosensitive member in Comparative Example 2-1 was produced in the same manner.

[Comparative example 2-2]

Comparative Example was produced in the same manner as in Example 2-4, except that 0.5 part of acetophenone was used instead of 0.5 part of Exemplary Compound (1) in preparing the coating liquid for charge generation layer formation in Example 2-4 Electrophotographic photosensitive member in 2-2.

[Comparative example 2-3]

In addition to using 0.5 parts of 2-(dimethylamino)-1-(4-morpholinophenyl)-2-benzyl-1-butanone instead of the coating used in the preparation of the charge generation layer in Example 2-4 An electrophotographic photosensitive member in Comparative Example 2-3 was produced in the same manner as in Example 2-4 except for 0.5 parts of Exemplary Compound (1) in the solution.

[Comparative example 2-4]

In addition to using 0.5 parts of 3-chloro-4-fluoroacetophenone instead of 0.5 parts of the exemplary compound (1) in the preparation of the coating liquid for forming the charge generation layer in Example 2-4, in the same manner as in Example 2-4 Electrophotographic photosensitive members in Comparative Examples 2-4 were produced in the same manner as in .

[Evaluation of Electrophotographic Photosensitive Members in Examples 2-1 to 2-11 and Comparative Examples 2-1 to 2-4]

The ghost images of the electrophotographic photosensitive members of Examples 2-1 to 2-11 and Comparative Examples 2-1 to 2-4 were evaluated.

A laser beam printer (trade name: Color LaserJet CP3525dn) manufactured by Hewlett Packard Japan, Ltd. was modified to be used as an electrophotographic apparatus for evaluation. As a result of modification, pre-exposure light is not emitted and charging conditions and image exposure are variably controlled. In addition, the produced electrophotographic photosensitive member was mounted in a process cartridge for cyan and attached to a position of the process cartridge for cyan so that it could be operated without mounting process cartridges for other colors to the laser beam printer main body.

When outputting an image, only a process cartridge for cyan is attached to the main body to output a monochrome image using only cyan toner.

The charging conditions and image exposure were adjusted to set the initial potential at -500 V in the dark area and -100 V in the light area under a normal temperature and normal humidity environment of 23° C./55% RH. In the measurement of the surface potential of a drum-shaped electrophotographic photosensitive member for potential setting, a cartridge was modified and a potential probe (trade name: model 6000B-8, manufactured by Trek Japan Co., Ltd.) was installed at the developing position. The potential of the central portion of the cylindrical electrophotographic photosensitive member was measured with a surface potential meter (trade name: model 344, manufactured by Trek Japan Co., Ltd.).

Ghost images were then evaluated under the same conditions. Subsequently, a paper passing durability test of 1,000 sheets was performed, and ghost images immediately after the durability test and after 15 hours were evaluated. Table 1 describes the evaluation results under normal temperature and normal humidity environment.

Subsequently, the electrophotographic photosensitive member was left standing together with the electrophotographic apparatus for evaluation under a low-temperature and low-humidity environment of 15° C./10% RH for 3 days to evaluate ghost images. Under the same conditions, a paper passing durability test of 1,000 sheets was performed, and ghost images immediately after the durability test and after 15 hours were evaluated. The evaluation results under low-temperature and low-humidity environment are also described in Table 1.

In the paper passing durability test, an image of character E at a printing rate of 1% was formed on A4 size plain paper in cyan monochrome.

The ghost images were evaluated as follows. The evaluation was based on a total of 8 ghost images continuously output in the following order: a solid white image was output on the first sheet, 4 types of ghost images were output on a total of 4 sheets, a solid black image was output on one sheet, and Again, four types of ghost images are output on a total of four sheets. The ghost image includes: 4 solid black square images with 25 mm sides arranged in parallel at equal intervals within a width range of 30 mm from the starting position of the printed image (10 mm from the upper end of the paper) as a solid white background. In the range below the 30 mm width range from the start position of the print image, 4 types of halftone print patterns are printed so as to be graded.

Type 4 ghost images are images arranged in a range below the 30 mm width range from the start position of the printed image, differing only in the halftone pattern. Halftone patterns include the following 4 categories:

(1) A printed pattern with 1 dot and 1 space along the transverse direction* (laser exposure);

(2) A printed pattern with 2 dots and 2 spaces along the horizontal direction* (laser exposure);

(3) A printed pattern (laser exposure) with 2 dots and 3 spaces in the transverse direction*; and

(4) Print pattern (laser exposure) of the pattern of "Kuima" (similar to jumping of a horse in a chess board) (like the movement of a "Kuima" piece in Japanese Chess similar to a jumping direction of a horse, with a movement in 6 pattern of 2 dots printed in squares).

*: Landscape refers to the scanning direction of the laser scanner (horizontal direction of the output paper).

The ghost images are classified into the following grades. The effect of the present invention was judged to be insufficient in ranks 4, 5 and 6.

Level 1: Ghosts are not visible in any ghost map.

Level 2: Ghosts are vaguely visible in certain ghost images.

Level 3: Ghosts are vaguely visible in any ghost map.

Grade 4: Ghosting is visible in certain ghosting images.

Grade 5: Ghosts are visible in any ghost image.

Rank 6: Ghosts are clearly visible in specific ghost images.

Table 1: Evaluation results of ghost images

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the claims is to be interpreted broadly so as to encompass all modifications and equivalent structures and functions.

Claims (17)

1. An electrophotographic photosensitive member comprising: a support; and a charge generation layer and a charge transport layer formed on the support;

wherein the charge generation layer comprises: a charge generating substance; and an amine compound represented by the following formula (1);

wherein,

R¹to R⁵Each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, an amino group having a substituent, or a substituted or unsubstituted cyclic amino group; and

R¹to R⁵Is an amino group substituted with a substituted or unsubstituted aryl group, an amino group substituted with a substituted or unsubstituted alkyl group, or a substituted or unsubstituted cyclic amino group.

2. The electrophotographic photosensitive member according to claim 1, wherein R¹To R⁵Is an amino group substituted with a substituted or unsubstituted alkyl group.

3. The electrophotographic photosensitive member according to claim 2, wherein the amino group substituted with a substituted or unsubstituted alkyl group is a dialkylamino group.

4. The electrophotographic photosensitive member according to claim 3, wherein the dialkylamino group is a dimethylamino group or a diethylamino group.

5. The electrophotographic photosensitive member according to claim 1, wherein the amine compound is an amine compound represented by the following formula (2):

wherein R is⁶And R⁷Each independently represents a methyl group or an ethyl group.

6. The electrophotographic photosensitive member according to claim 1, wherein R¹To R⁵At least one of which is a substituted or unsubstituted cyclic amino group.

7. The electrophotographic photosensitive member according to claim 6, wherein the substituted or unsubstituted cyclic amino group is a morpholino group or a piperidino group.

8. The electrophotographic photosensitive member according to claim 1, wherein the amine compound is an amine compound represented by the following formula (3):

9. the electrophotographic photosensitive member according to claim 1, wherein a content of the amine compound in the charge generation layer is 0.1% by mass or more and 20% by mass or less with respect to the charge generation substance.

10. The electrophotographic photosensitive member according to claim 1, wherein the charge generating substance is a phthalocyanine crystal.

11. The electrophotographic photosensitive member according to claim 1, wherein the charge generation layer is a layer comprising a phthalocyanine crystal in which an amine compound represented by formula (1) is contained.

12. The electrophotographic photosensitive member according to claim 11, wherein a content of the amine compound in the phthalocyanine crystal is 0.05% by mass or more and 3.0% by mass or less.

13. The electrophotographic photosensitive member according to claim 10 or 11, wherein the phthalocyanine crystal is a gallium phthalocyanine crystal.

14. The electrophotographic photosensitive member according to claim 13, wherein the gallium phthalocyanine crystal is a hydroxygallium phthalocyanine crystal of a crystalline form having peaks at bragg angles 2 θ of 7.4 ° ± 0.3 ° and 28.2 ° ± 0.3 ° in X-ray diffraction with CuK α radiation.

15. A process cartridge detachably mountable to a main body of an electrophotographic apparatus, characterized in that the electrophotographic photosensitive member according to any one of claims 1 to 14 and at least one device selected from the group consisting of a charging device, a developing device, a transferring device and a cleaning device are integrally supported to form the process cartridge.

16. An electrophotographic apparatus, characterized in that it comprises:

the electrophotographic photosensitive member according to any one of claims 1 to 14; and

a charging device, an image exposure device, a developing device, and a transfer device.

17. A phthalocyanine crystal characterized by comprising a compound represented by the following formula (1) in the phthalocyanine crystal:

wherein

R¹To R⁵Each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, a carboxyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, an amino group having a substituent, or a substituted or unsubstituted cyclic amino group; and

R¹to R⁵Is an amino group substituted with a substituted or unsubstituted aryl group, an amino group substituted with a substituted or unsubstituted alkyl group, or a substituted or unsubstituted cyclic amino group.