JP2015106136A - Electrophotographic photoreceptor, process cartridge and electrophotographic device, and phthalocyanine crystal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor with the photo memory inhibited, and a process cartridge and an electrophotographic device having the electrophotographic photoreceptor.SOLUTION: A photosensitive layer of an electrophotographic photoreceptor comprises a phthalocyanine crystal in which a dicyanoethylene compound represented by formula (1) is contained.

Description

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

  A phthalocyanine pigment having high sensitivity is often used as a charge generating material used for an electrophotographic photoreceptor.

  However, an electrophotographic photosensitive member using a phthalocyanine pigment has excellent sensitivity characteristics. On the other hand, the electrophotographic photosensitive member is exposed to light leaking from the outside of the process cartridge or the electrophotographic apparatus. There was a problem that photo memory was likely to occur. Photo memory is a phenomenon in which carriers stay in the irradiated area (irradiated area) and a potential difference occurs between the unirradiated area (non-irradiated area) and image quality (image reproducibility). ) Is a phenomenon that can be a cause of lowering.

  Patent Documents 1 and 2 describe a technique in which a phthalocyanine pigment and an organic electron acceptor compound are used in combination, and a technique in which a pigment-sensitized dopant having an electron-accepting molecule is contained in the charge generation layer.

JP 2006-72304 A JP 2008-15532 A

  However, as a result of the study by the present inventors, the techniques described in Patent Documents 1 and 2 have not been able to sufficiently improve the photomemory.

  An object of the present invention is to provide an electrophotographic photosensitive member in which photo memory is suppressed, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member.

  Another object of the present invention is to provide a phthalocyanine crystal containing a specific dicyanoethylene compound in the crystal.

The present invention relates to an electrophotographic photosensitive member having a support and a photosensitive layer formed on the support,
The electrophotographic photosensitive member is characterized in that the photosensitive layer contains a phthalocyanine crystal containing a compound represented by the following formula (1) in the crystal.

(In formula (1), R ¹ and R ² are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted thienyl group, A substituted or unsubstituted piperidyl group or a substituted amino group is indicated.)

  Further, the present invention integrally supports the electrophotographic photosensitive member and at least one means selected from the group consisting of a charging means, a developing means, a transfer means, and a cleaning means, and is detachable from the main body of the electrophotographic apparatus. It is a process cartridge characterized by being.

  The present invention also provides an electrophotographic apparatus having the electrophotographic photosensitive member, and a charging unit, an exposure unit, a developing unit, and a transfer unit.

  The present invention also provides a phthalocyanine crystal characterized in that the compound represented by the formula (1) is contained in the crystal.

  According to the present invention, it is possible to provide an electrophotographic photosensitive member in which photo memory is suppressed, and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member. Moreover, according to this invention, the phthalocyanine crystal | crystallization which contains a specific dicyanoethylene compound in a crystal | crystallization can be provided.

1 is a diagram illustrating an example of a schematic configuration of an electrophotographic apparatus including a process cartridge having the electrophotographic photosensitive member of the present invention. 2 is a powder X-ray diffraction pattern of a hydroxygallium phthalocyanine crystal obtained in Example 1. FIG.

  The photosensitive layer of the electrophotographic photoreceptor of the present invention contains a phthalocyanine crystal containing a compound represented by the following formula (1) (hereinafter also referred to as a dicyanoethylene compound represented by the formula (1)) in the crystal.

R ¹ and R ^{2 in} formula (1) are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted thienyl group, a substituted Alternatively, it represents an unsubstituted piperidyl group or a substituted amino group.

  Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the aryl group include a phenyl group and a naphthyl group.

  Examples of the substituent that each of the above groups may have include an alkyl group such as a methyl group, an ethyl group, a propyl group, and a butyl group, an aryl group such as a phenyl group, a naphthyl group, and a phenalenyl group, a fluorine atom, and a chlorine atom. , Halogen atoms such as bromine atom, alkyl group-substituted amino groups such as dimethylamino group and diethylamino group, hydroxyalkyl group-substituted amino groups such as di (hydroxymethyl) amino group and di (hydroxyethyl) amino group, and dihydroxy Examples include hydroxy group-substituted amino groups such as amino groups, aryl group-substituted amino groups such as diphenylamino groups, ditolylamino groups, and dixylylamino groups, amino groups (unsubstituted amino groups), and hydroxy groups.

In addition, R ¹ and R ² in the above formula (1) are substituted with an aryl group, a pyridyl group, a piperidyl group, an amino group substituted with an alkyl group or an aryl group, or a secondary amine or a tertiary amine. An aryl group is preferred.

  Specific examples (exemplary compounds) of the dicyanoethylene compound represented by the above formula (1) are shown below, but the present invention is not limited thereto. Further, Table 1 shows the dipole moment and LUMO of specific examples.

  Hereinafter, the exemplary compounds are also referred to as exemplary compounds (1-1) to (1-24) in order.

  The present inventors consider that among various cyanoethylene compounds, the dicyanoethylene compound represented by the formula (1) has good matching with the phthalocyanine skeleton of the phthalocyanine crystal. And the cyano group which is an electron withdrawing group of the dicyanoethylene compound represented by the formula (1) causes distortion in the spatial expansion of the electron orbital in the molecule of the phthalocyanine crystal, and draws out residual carriers in the phthalocyanine crystal. I believe that The present inventors believe that this leads to improvement of photo memory. Furthermore, it is considered that when the dicyanoethylene compound represented by the formula (1) is contained in the phthalocyanine crystal, the cyano group causes a large distortion due to the spatial expansion of the electron orbit in the molecule of the phthalocyanine crystal. It is believed that this serves to efficiently extract residual carriers in the phthalocyanine crystal.

  The LUMO obtained from the molecular orbital calculation result at the density functional calculation B3LYP / 6-31G level of the dicyanoethylene compound represented by the formula (1) is −2.4 eV to −2.0 eV. Is preferred. It is considered that the residual carrier in the phthalocyanine crystal can be more easily extracted when it is within the above range.

  Moreover, it is preferable that the dipole moment obtained from the result of molecular orbital calculation at the density functional calculation B3LYP / 6-31G level of the dicyanoethylene compound represented by the above formula (1) is 6.5 debye or more. . In the above range, it is considered that distortion can be sufficiently brought about in the spatial expansion of the electron orbit in the molecule of the phthalocyanine crystal. More preferably, it is 6.5 debye or more and 12.7 debye or less, More preferably, it is 6.5 debye or more and 11.5 debey or less.

  For the molecular orbital calculation, density functional theory (DFT) using Gaussian basis was used. The time-dependent density functional theory (TDDFT) was used for the calculation of the transition dipole moment and LUMO. In DFT, the exchange correlation interaction is approximated by a functional of one electron potential expressed by electron density (meaning function). In the present invention, the weight of each parameter related to exchange and correlation energy is defined using B3LYP which is a mixed functional. Moreover, 6-31G was applied to all atoms as a basis function.

  When the photosensitive layer has a charge generation layer and a charge transport layer formed on the charge generation layer, the charge generation layer may contain a phthalocyanine crystal containing the compound represented by the formula (1) in the crystal. preferable.

  Examples of the phthalocyanine constituting the phthalocyanine crystal include metal-free phthalocyanine and metal phthalocyanine, which may have an axial ligand and / or a substituent.

  Among the phthalocyanines, oxytitanium phthalocyanine and gallium phthalocyanine are preferable because they have particularly high sensitivity and easily generate photomemory.

  Among gallium phthalocyanines, hydroxygallium phthalocyanine and chlorogallium phthalocyanine are preferable. Among the hydroxygallium phthalocyanines, crystalline gallium phthalocyanine crystals having peaks (strong peaks) at 7.4 ° and 28.3 ° with a Bragg angle of 2θ ± 0.2 ° in the X-ray diffraction of CuKα rays are preferable. Among chlorogallium phthalocyanines, crystals having peaks (strong peaks) at 7.4 °, 16.6 °, 25.5 ° and 28.0 ° with a Bragg angle 2θ ± 0.2 ° in X-ray diffraction of CuKα rays A chlorogallium phthalocyanine crystal in the form is preferred.

  Among the oxytitanium phthalocyanines, a crystalline oxytitanium phthalocyanine crystal having a peak (strong peak) at 27.2 ° with a Bragg angle 2θ ± 0.2 ° in the X-ray diffraction of CuKα rays is preferable.

  Among these, a crystalline hydroxygallium phthalocyanine crystal having peaks at 7.4 ° and 28.3 ° with a Bragg angle 2θ ± 0.2 ° in X-ray diffraction of CuKα rays is particularly preferable.

  The content of the compound represented by the formula (1) contained in the phthalocyanine crystal is preferably 0.01% by mass or more and 3% by mass or less from the viewpoint of suppression of photomemory. More preferably, it is 0.01 mass% or more and 2.9 mass% or less.

  The phthalocyanine crystal containing the compound represented by the formula (1) in the crystal means that the compound represented by the formula (1) is incorporated in the crystal.

  A method for producing a phthalocyanine crystal containing the compound represented by the formula (1) in the crystal will be described.

  The phthalocyanine crystal containing the compound represented by the formula (1) in the crystal is crystal-converted by wet milling treatment by mixing the phthalocyanine obtained by the acid pasting method and the compound represented by the formula (1) with a solvent. Obtained by the process.

  The milling process performed here is, for example, a process performed using a milling apparatus such as a sand mill or a ball mill together with a dispersant such as glass beads, steel beads, or alumina balls. The milling time is preferably about 1 to 200 hours. A particularly preferable method is to take a sample every 5 to 10 hours and confirm the Bragg angle of the crystal. The amount of the dispersant used in the milling treatment is preferably 10 to 50 times that of gallium phthalocyanine on a mass basis. Examples of the solvent used include N, N-dimethylformamide, N, N-dimethylacetamide, N-methylformamide, N-methylacetamide, N-methylpropioamide, and N-methyl-2-pyrrolidone. Examples thereof include amide solvents, halogen solvents such as chloroform, ether solvents such as tetrahydrofuran, and sulfoxide solvents such as dimethyl sulfoxide. The amount of solvent used is preferably 5 to 30 times that of phthalocyanine on a mass basis. The amount of the compound represented by the formula (1) is preferably 0.1 to 30 times that of phthalocyanine on a mass basis.

  Moreover, you may use the dicyanoethylene compound shown by Formula (1) in combination of 2 or more types.

  In the present invention, whether the phthalocyanine crystal contains the compound represented by the formula (1) in the crystal is analyzed for data of H-NMR measurement and thermogravimetric (TG) measurement of the obtained phthalocyanine crystal. Is determined by

  For example, when a milling treatment with a solvent capable of dissolving the compound represented by the formula (1) or a washing step after the milling treatment is performed, the obtained phthalocyanine crystal is subjected to H-NMR measurement. When the compound represented by the formula (1) is detected, it can be determined that the compound represented by the formula (1) is contained in the crystal.

  On the other hand, when the compound represented by the formula (1) is insoluble in the solvent used for the milling treatment and insoluble in the washing solvent after the milling treatment, the obtained phthalocyanine crystal is subjected to H-NMR measurement, and the formula (1) When the indicated compound was detected, it was judged by the following method.

  A phthalocyanine crystal obtained by adding the compound represented by the formula (1), a phthalocyanine crystal prepared in the same manner except that the compound represented by the formula (1) is not added, and a compound alone represented by the formula (1) TG is measured individually. The TG measurement result of the phthalocyanine crystal obtained by adding the compound represented by the formula (1) shows that the phthalocyanine crystal obtained without adding the compound represented by the formula (1), the compound represented by the formula (1), When the individual measurement results of can be interpreted as simply mixing at a predetermined ratio. In this case, it can be interpreted that the mixture of the phthalocyanine crystal and the compound represented by the formula (1), or the compound represented by the formula (1) is simply attached to the surface of the phthalocyanine crystal.

  On the other hand, the TG measurement result of the phthalocyanine crystal obtained by adding the compound represented by the formula (1) is less than the TG measurement result of the phthalocyanine crystal obtained without adding this compound. If the weight loss is increasing at a temperature higher than the temperature at which is finished. In this case, it can be determined that the compound represented by the formula (1) is contained in the crystal.

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

[H-NMR measurement]
Measuring instrument used: BRUKER, AVANCE III 500
Solvent: Bisulfuric acid (D ₂ SO ₄ )

[TG measurement]
Measuring instrument used: Seiko Denshi Kogyo Co., Ltd., TG / DTA simultaneous measuring device (trade name: TG / DTA220U)
Atmosphere: Nitrogen flow (300 m ² / min)
Measurement range: 35 ° C to 600 ° C
Temperature rising speed: 10 ° C / min

[Powder X-ray diffraction measurement]
Measuring instrument used: Rigaku Denki Co., Ltd., X-ray diffractometer RINT-TTRII
X-ray tube: Cu
Tube voltage: 50KV
Tube current: 300mA
Scanning method: 2θ / θ scan Scanning speed: 4.0 ° / min
Sampling interval: 0.02 °
Start angle (2θ): 5.0 °
Stop angle (2θ): 40.0 °
Attachment: Standard specimen holder Filter: Non-use incident Monochrome: Use counter monochromator: Non-use divergence slit: Open divergence length limit slit: 10.00mm
Scattering slit: Open light receiving slit: Open flat plate monochromator: Usage counter: Scintillation counter The phthalocyanine crystal containing the compound represented by the formula (1) in the crystal has an excellent function as a photoconductor, and other than the electrophotographic photosensitive member. Can also be applied to solar cells, sensors, switching elements, and the like.

  Next, a case where a phthalocyanine crystal containing the compound represented by the formula (1) of the present invention in the crystal is applied as a charge generating material in an electrophotographic photoreceptor will be described. The electrophotographic photoreceptor of the present invention has a support and a photosensitive layer formed on the support.

  The photosensitive layer is a single layer type photosensitive layer containing a charge transport material and a charge generation material in the same layer, or a stacked type separated into a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material. There is a (functional separation type) photosensitive layer. From the viewpoint of electrophotographic characteristics, a laminated photosensitive layer is preferred. Of the laminated photosensitive layers, those having a charge generation layer and a charge transport layer formed on the charge generation layer are preferable from the viewpoint of electrophotographic characteristics.

  The support is preferably a conductive material (conductive support). For example, a support made of a metal (alloy) such as aluminum or stainless steel, or a support made of a metal, plastic, paper, or the like provided with a conductive film on the surface can be given.

  Examples of the shape of the support include a cylindrical shape and a film shape.

  An undercoat layer (also referred to as an intermediate layer) having a barrier function or an adhesive function can be provided between the support and the photosensitive layer.

  The undercoat layer can be formed by forming a coating film of a coating solution for an undercoat layer prepared by dissolving a resin in a solvent, and drying the obtained coating film.

  Examples of the resin used for the undercoat layer include polyvinyl alcohol, polyethylene oxide, ethyl cellulose, methyl cellulose, casein, polyamide (such as nylon 6, nylon 66, nylon 610, copolymer nylon and N-alkoxymethylated nylon), glue, Examples include gelatin.

  The thickness of the undercoat layer is preferably 0.3 to 5.0 μm.

  In addition, a conductive layer can be provided between the support and the undercoat layer or the photosensitive layer for the purpose of concealing the surface of the support, concealing defects, suppressing interference fringes, and the like.

  The conductive layer forms a coating film of a conductive layer coating solution prepared by dispersing conductive particles such as carbon black, metal particles, and metal oxide particles in a suitable solvent together with a binder resin. Can be formed by drying / curing. Examples of the metal oxide particles include tin oxide, indium oxide, and titanium oxide.

  The thickness of the conductive layer is preferably 5 to 40 μm, and more preferably 10 to 30 μm.

  When the photosensitive layer is a laminated photosensitive layer, the charge generation layer first disperses a phthalocyanine crystal and a binder resin containing the compound represented by the formula (1) as a charge generation substance in the solvent in a solvent. Thus, a charge generation layer coating solution is prepared. A charge generation layer can be formed by forming a coating film of this charge generation layer coating solution and drying the resulting coating film.

  The thickness of the charge generation layer is preferably 0.05 to 1 μm, and more preferably 0.1 to 0.3 μm.

  The content of the charge generation material in the charge generation layer is preferably 30 to 90% by mass, and more preferably 50 to 80% by mass with respect to the total mass of the charge generation layer.

  As the charge generation material used in the charge generation layer, in addition to the phthalocyanine crystal, a substance other than the phthalocyanine pigment (for example, an azo pigment) may be used in combination. In that case, the phthalocyanine crystal containing the compound represented by the formula (1) in the crystal is preferably 50% by mass or more based on the total mass of the charge generating substance.

  Examples of the binder resin used for the charge generation layer include polyester, acrylic resin, phenoxy resin, polycarbonate, polyvinyl butyral, polystyrene, polyvinyl acetate, polysulfone, polyarylate, vinylidene chloride, acrylonitrile copolymer, and polyvinyl benzal. Can be mentioned. Among these, polyvinyl butyral and polyvinyl benzal are preferable.

  When the photosensitive layer is a laminate type photosensitive layer, the charge transport layer forms a coating film of the coating solution for the charge transport layer prepared by dissolving the charge transport material and the binder resin in a solvent. It can be formed by drying.

  The thickness of the charge transport layer is preferably 5 to 40 μm, and more preferably 10 to 25 μm.

  The content of the charge transport material in the charge transport layer is preferably 20 to 80% by mass and more preferably 30 to 60% by mass with respect to the total mass of the charge transport layer.

  Examples of the charge transport material include triarylamine compounds, hydrazone compounds, stilbene compounds, pyrazoline compounds, oxazole compounds, thiazole compounds, triallylmethane compounds, and the like. Of these, 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, and the like. Among these, polycarbonate and polyarylate are preferable.

  When the photosensitive layer is a single-layer type photosensitive layer, the single-layer type photosensitive layer first includes a phthalocyanine crystal containing a compound represented by formula (1) as a charge generating substance in the crystal, a charge transporting substance, and a binder. A coating solution for a single-layer type photosensitive layer is prepared by dispersing a resin in a solvent. And a single layer type photosensitive layer can be formed by forming a coating film of a coating solution for a single layer type photosensitive layer and drying the coating film.

  A protective layer may be provided on the photosensitive layer for the purpose of protecting the photosensitive layer.

The protective layer can be formed by forming a coating film of a coating solution for a protective layer prepared by dissolving a resin in a solvent, and drying / curing the coating film. When the coating film is cured, it can be cured by heating, electron beam, ultraviolet rays or the like. Examples of the resin used for the protective layer include polyvinyl butyral, polyester, polycarbonate, nylon, polyimide, polyarylate, polyurethane, styrene-butadiene copolymer, styrene-acrylic acid copolymer, and styrene-acrylonitrile copolymer.
The thickness of the protective layer is preferably 0.05 to 20 μm.

  Examples of the method for applying the coating solution for each layer include a dip coating method (dipping method), a spray coating method, a spinner coating method, a bead coating method, a blade coating method, and a beam coating method.

  In addition, the layer serving as the surface layer of the electrophotographic photosensitive member may contain lubricating particles such as conductive particles, an ultraviolet absorber, and fluorine atom-containing resin particles. Examples of the conductive particles include metal oxide particles such as tin oxide particles.

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

  Reference numeral 1 denotes a cylindrical (drum-shaped) electrophotographic photosensitive member, which is rotationally driven around a shaft 2 at a predetermined peripheral speed (process speed) in the direction of an arrow.

  The surface (circumferential surface) of the electrophotographic photosensitive member 1 is charged to a predetermined positive or negative potential by a charging unit (primary charging unit) 3 during the rotation process. Next, the surface of the electrophotographic photosensitive member 1 is irradiated with exposure light (image exposure light) 4 from exposure means (image exposure means) (not shown), and an electrostatic latent image corresponding to target image information is electrophotographic. It is formed on the surface of the photoreceptor 1. The exposure light 4 is light that has been intensity-modulated in response to a time-series electrical digital image signal of target image information that is output from an exposure means such as slit exposure or laser beam scanning exposure.

  The electrostatic latent image formed on the surface of the electrophotographic photosensitive member 1 is developed (regular development or reversal development) with toner contained in the developing means 5, and a toner image is formed on the surface of the electrophotographic photosensitive member 1. Is done. The toner image formed on the surface of the electrophotographic photoreceptor 1 is transferred to the transfer material P by the transfer unit 6. At this time, a voltage having a polarity opposite to the toner charge is applied to the transfer means 6 from a power source (not shown). When the transfer material P is paper, the transfer material P is taken out from a paper feeding unit (not shown) and is synchronized with the rotation of the electrophotographic photosensitive member 1 between the electrophotographic photosensitive member 1 and the transfer means 6. Are sent.

  The transfer material P onto which the toner image has been transferred from the electrophotographic photosensitive member 1 is separated from the surface of the electrophotographic photosensitive member 1, conveyed to the fixing unit 8, and subjected to a fixing process of the toner image. Printed out to the outside of the electrophotographic apparatus as (print, copy).

  The surface of the electrophotographic photosensitive member 1 after the toner image is transferred to the transfer material P is cleaned by the cleaning means 7 after removal of adhered substances such as toner (transfer residual toner). In recent years, a cleaner-less system has also been developed, and there are cases where untransferred toner can be removed by developing means or the like. Further, the surface of the electrophotographic photosensitive member 1 is subjected to charge removal processing by pre-exposure light from pre-exposure means (not shown), and then repeatedly used for image formation. When the charging unit 3 is a contact charging unit using a charging roller or the like, the pre-exposure unit is not always necessary.

  In the present invention, among the components selected from the above-described electrophotographic photosensitive member 1, charging unit 3, developing unit 5, cleaning unit 7 and the like, a plurality of components are housed in a container and supported integrally. Form. The process cartridge can be configured to be detachable from the main body of the electrophotographic apparatus. For example, at least one unit selected from the charging unit 3, the developing unit 5, and the cleaning unit 7 is integrally supported together with the electrophotographic photosensitive member 1 to form a cartridge. Then, the process cartridge 9 can be detachably attached to the main body of the electrophotographic apparatus using the guide means 10 such as a rail of the main body of the electrophotographic apparatus.

  When the electrophotographic apparatus is a copying machine, the exposure light 4 may be reflected light or transmitted light from a document. Alternatively, it may be light emitted by reading a document with a sensor, converting it into a signal, scanning a laser beam performed according to this signal, driving an LED array, driving a liquid crystal shutter array, or the like.

  The electrophotographic photoreceptor 1 of the present invention can be widely applied to copying machines, laser beam printers, CRT printers, LED printers, FAX, liquid crystal printers, laser plate making, and the like.

  Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the present invention is not limited to these. In addition, the film thickness of the Example and the comparative example was calculated | required in conversion of specific gravity from the eddy current type film thickness meter (FISCHERSCOPE, the Fischer Instruments company make) or the mass per unit area. In the examples, “part” means “part by mass”.

[Crystal Production Example 1]
15 parts of chlorogallium phthalocyanine was dissolved in 450 parts of concentrated sulfuric acid at 10 ° C. and stirred for 1 hour, then dropped into 2300 parts of ice water, reprecipitated and filtered. The residue on the filter paper was dispersed and washed with 2% aqueous ammonia, then washed with ion-exchanged water, and dried. Thus, 13 parts of hydroxygallium phthalocyanine having peaks at 6.9 and 26.6 ° with a Bragg angle 2θ ± 0.2 ° in CuKα characteristic X-ray diffraction were obtained (acid pasting method).

  Milling treatment of 0.5 parts of the obtained hydroxygallium phthalocyanine, 0.5 parts of exemplary compound (1-1), and 9.5 parts of N, N-dimethylformamide together with 15 parts of glass beads having a diameter of 1 mm using a ball mill. The reaction was performed at room temperature (23 ° C.) for 70 hours. Gallium phthalocyanine crystals were taken out from this dispersion using N, N-dimethylformamide, filtered, and the filter was thoroughly washed with tetrahydrofuran. The filtered product was vacuum-dried to obtain 0.43 hydroxygallium phthalocyanine crystal. The powder X-ray diffraction pattern of the obtained crystals is shown in FIG.

  It was confirmed by H-NMR measurement that 0.38% by mass of the exemplified compound (1-1) was contained in the hydroxygallium phthalocyanine crystal in terms of the proton ratio. Since the exemplary compound (1-1) is compatible with N, N-dimethylformamide, it can be seen that the exemplary compound (1-1) is contained in the hydroxygallium phthalocyanine crystal.

[Crystal Production Examples 2-3 and 5-10]
Crystal Production Example 1 except that Exemplified Compound (1-1) was changed to Exemplified Compounds (1-2) to (1-3) and (1-5) to (1-10) in Crystal Production Example 1, respectively. Was manufactured and measured in the same manner. The results are shown in Table 2. The exemplary compounds (1-2) to (1-3) and (1-5) to (1-10) are compatible with N, N-dimethylformamide. Therefore, exemplary compounds (1-2) to (1-3) and (1-5) to (1-10) are contained in the hydroxygallium phthalocyanine crystal.

[Crystal Production Example 4]
In the crystal production example 1, it manufactured and measured similarly to the crystal manufacture example 1 except having changed the exemplary compound (1-1) into the exemplary compound (1-4). Exemplified compound (1-4) was incompatible with N, N-dimethylformamide. Therefore, it was confirmed by TG measurement that 0.86% by mass of the exemplified compound (1-4) was contained in the hydroxygallium phthalocyanine crystal. The results are shown in Table 2.

[Crystal Production Example 11]
In Crystal Production Example 1, production and measurement were carried out in the same manner as in Crystal Production Example 1, except that 0.1 part of Exemplified Compound (1-1) and milling time were changed to 7 hours. The results are shown in Table 2.

[Crystal Production Example 12]
In Crystal Production Example 1, production and measurement were conducted in the same manner as in Crystal Production Example 1, except that 3 parts of Example Compound (1-1) and milling time were changed to 160 hours. The results are shown in Table 2.

[Crystal Production Example 13]
In Crystal Production Example 1, production and measurement were conducted in the same manner as in Crystal Production Example 1, except that 0.05 part of Exemplified Compound (1-1) and milling treatment time were changed to 6 hours. The results are shown in Table 2.

[Crystal Production Example 14]
In Crystal Production Example 1, production and measurement were conducted in the same manner as in Crystal Production Example 1 except that 5 parts of Exemplified Compound (1-1) and milling time were changed to 150 hours. The results are shown in Table 2.

[Crystal Production Examples 15 to 16]
In the crystal production example 1, it manufactured and measured similarly to the crystal manufacture example 1 except having changed the exemplary compound (1-1) into the following exemplary compounds (2-1)-(2-2), respectively. The results are shown in Table 2.

[Crystal Production Example 17]
In the crystal manufacture example 1, it manufactured and measured similarly to the crystal manufacture example 1 except not having added exemplary compound (1-1). The results are shown in Table 2.

[Example 1]
An aluminum cylinder (JIS-A3003, aluminum alloy) having a diameter of 24 mm and a length of 257.5 mm was used as a support (conductive support).

  Next, barium sulfate particles coated with tin oxide (trade name: Pastoran PC1, manufactured by Mitsui Mining & Smelting Co., Ltd.), titanium oxide particles (trade name: TITANIXJR, manufactured by Teika Co., Ltd.), 15 parts, resol type 43 parts of phenolic resin (trade name: Phenolite J-325, manufactured by Dainippon Ink & Chemicals, Inc., solid content 70% by mass), 0.015 part of silicone oil (trade name: SH28PA, manufactured by Toray Silicone Co., Ltd.) By placing 3.6 parts of silicone resin particles (trade name: Tospearl 120, manufactured by Toshiba Silicone Co., Ltd.), 50 parts of 2-methoxy-1-propanol, and 50 parts of methanol in a ball mill, and dispersing for 20 hours. A conductive layer coating solution was prepared. This conductive layer coating solution was dip-coated on a support to form a coating film, and the resulting coating film was heated and cured at 140 ° C. for 1 hour to form a conductive layer having a thickness of 15 μm. .

  Next, 10 parts of copolymer nylon (trade name: Amilan CM8000, manufactured by Toray Industries, Inc.) and 30 parts of methoxymethylated 6 nylon (trade name: Toresin EF-30T, manufactured by Teikoku Chemical Co., Ltd.) are mixed with methanol. An undercoat layer coating solution was prepared by dissolving in a mixed solvent of 400 parts / 200 parts of n-butanol. This undercoat layer coating solution is applied onto the conductive layer by dip coating to form a coating film, and the resulting coating film is dried at 80 ° C. for 6 minutes to form an undercoat layer having a thickness of 0.45 μm. did.

  Next, 10 parts of a hydroxygallium phthalocyanine crystal (charge generation material) obtained in Crystal Production Example 1, 5 parts of polyvinyl butyral (trade name: ESREC BX-1, manufactured by Sekisui Chemical Co., Ltd.), and 250 parts of cyclohexanone The mixture was placed in a sand mill using glass beads having a diameter of 1 mm and dispersed for 4 hours. Thereafter, 250 parts of ethyl acetate was added thereto to prepare a charge generation layer coating solution. The charge generation layer coating solution is dip-coated on the undercoat layer to form a coating film, and the resulting coating film is dried at 100 ° C. for 10 minutes to form a charge generation layer having a thickness of 0.17 μm. Formed.

  Next, 40 parts of a compound represented by the following formula (C-1) (charge transporting substance (hole transporting compound)),

  40 parts of a compound represented by the following formula (C-2) (charge transporting material (hole transporting compound)),

  Then, 100 parts of polycarbonate (trade name: Iupilon Z200, manufactured by Mitsubishi Engineering Plastics Co., Ltd.) was dissolved in a mixed solvent of 600 parts of monochlorobenzene / 200 parts of dimethoxymethane to prepare a coating solution for a charge transport layer. The charge transport layer coating solution was dip-coated on the charge generation layer to form a coating film, and the coating film was dried at 120 ° C. for 30 minutes to form a charge transport layer having a thickness of 21 μm.

  In this way, a cylindrical (drum-shaped) electrophotographic photosensitive member of Example 1 was manufactured.

[Examples 2-14 and Comparative Examples 1-2]
In Example 1, an electrophotographic photoreceptor was produced in the same manner as in Example 1 except that the hydroxygallium phthalocyanine crystal obtained in Crystal Production Example 1 was changed to Crystal Production Examples 2-16.

[Comparative Example 3]
In Example 1, the hydroxygallium phthalocyanine crystal obtained in Crystal Production Example 1 was changed to Crystal Production Example 17 and the same as Example 1 except that 0.2 part of Example Compound (2-1) was added during the dispersion treatment. Thus, an electrophotographic photosensitive member was produced.

[Evaluation of Examples 1-14 and Comparative Examples 1-3]
The evaluation of the photo memory was performed using a modified machine of a laser beam printer (trade name: LaserJet Pro400Color M451dn) manufactured by Hewlett-Packard Company. As a remodeling point, the laser power was remodeled to 0.40 μJ / cm ² .

In the evaluation method of the photo memory, a part of the surface (circumferential surface) of the electrophotographic photosensitive member was shielded from light, and a non-shielded part (irradiation part) was irradiated with 1500 lux fluorescent lamp light for 5 minutes. Thereafter, the bright part potential of the surface of the electrophotographic photosensitive member is measured with the modified laser beam printer, and the difference (potential difference) ΔVl [V] between the bright part potential Vl of the irradiated part and the bright part potential Vl of the non-irradiated part ] Was evaluated as a photo memory.
ΔVl = Vl of irradiated part−Vl of non-irradiated part
The smaller the value of ΔVl is, the smaller the photo memory is suppressed.

  The results are shown in Table 2.

1 Electrophotographic photosensitive member 2 Axis 3 Charging means (primary charging means)
4 exposure light (image exposure light)
DESCRIPTION OF SYMBOLS 5 Developing means 6 Transfer means 7 Cleaning means 8 Fixing means 9 Process cartridge 10 Guide means P Transfer material

Claims (12)

In an electrophotographic photoreceptor having a support and a photosensitive layer formed on the support,
An electrophotographic photoreceptor, wherein the photosensitive layer contains a phthalocyanine crystal containing a compound represented by the following formula (1) in the crystal.

(In formula (1), R ¹ and R ² are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted thienyl group, A substituted or unsubstituted piperidyl group or a substituted amino group is indicated.) The photosensitive layer has a charge generation layer and a charge transport layer formed on the charge generation layer;
The electrophotographic photoreceptor according to claim 1, wherein the charge generation layer contains the phthalocyanine crystal containing the compound represented by the formula (1) in the crystal.   3. The electrophotographic photosensitive member according to claim 1, wherein the content of the compound represented by the formula (1) in the phthalocyanine crystal is 0.01% by mass or more and 3% by mass or less.   The dipole moment obtained from the result of molecular orbital calculation at the density functional calculation B3LYP / 6-31G level of the compound represented by the formula (1) is 6.5 debye or more. 2. The electrophotographic photosensitive member according to item 1.   Substituent of the substituted alkyl group, Substituent of the substituted aryl group, Substituent of the substituted pyridyl group, Substituent of the substituted thienyl group, Substituent of the substituted piperidyl group, and Substituted amino group Wherein the substituent is an alkyl group, an aryl group, a halogen atom, an alkyl group-substituted amino group, a hydroxyalkyl group-substituted amino group, a hydroxy group-substituted amino group, an aryl group-substituted amino group, an amino group or a hydroxy group. 5. The electrophotographic photosensitive member according to any one of 4 above. R ¹ and R ² in the formula (1) are each independently
An aryl group, a pyridyl group, a piperidyl group, an amino group substituted with an alkyl group or an aryl group, or
The electrophotographic photoreceptor according to claim 1, which is an aryl group substituted with a secondary amine or a tertiary amine.   The LUMO obtained from the result of molecular orbital calculation at the density functional calculation B3LYP / 6-31G level of the compound represented by the formula (1) is −2.4 eV to −2.0 eV. 6. The electrophotographic photosensitive member according to any one of 6 above.   The electrophotographic photoreceptor according to claim 1, wherein the phthalocyanine crystal is a hydroxygallium phthalocyanine crystal.   The electrophotographic photosensitive film according to claim 8, wherein the hydroxygallium phthalocyanine crystal is a hydroxygallium phthalocyanine crystal having peaks at 7.4 ° and 28.3 ° at a Bragg angle 2θ ± 0.2 in X-ray diffraction of CuKα rays. body.   An electrophotographic photosensitive member according to any one of claims 1 to 9, and at least one means selected from the group consisting of a charging means, a developing means, a transfer means, and a cleaning means are integrally supported, A process cartridge that is detachable from the main unit.   An electrophotographic apparatus comprising: the electrophotographic photosensitive member according to claim 1; a charging unit, an exposure unit, a developing unit, and a transfer unit. A phthalocyanine crystal comprising a compound represented by the following formula (1) in the crystal.

(In formula (1), R ¹ and R ² are each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted thienyl group, A substituted or unsubstituted piperidyl group or a substituted amino group is indicated.)

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